4 Material und Umwelt
Filtern
Dokumenttyp
- Zeitschriftenartikel (299)
- Vortrag (280)
- Posterpräsentation (137)
- Beitrag zu einem Tagungsband (43)
- Buchkapitel (23)
- Dissertation (6)
- Sonstiges (6)
- Beitrag zu einem Sammelband (5)
- Forschungsbericht (4)
- Forschungsdatensatz (3)
Sprache
- Englisch (812) (entfernen)
Schlagworte
- Biocides (50)
- Antimicrobial resistance (34)
- Corrosion (25)
- Bacteria (24)
- Biofilms (24)
- Ink (24)
- Leaching (23)
- Biofilm (19)
- MIC (19)
- Archaeometry (17)
- Nano (17)
- Sewage sludge (17)
- VOC (17)
- Evolution (15)
- Phosphorus (15)
- XRF (15)
- Bottom ash (14)
- Methanogens (14)
- OECD (14)
- Phosphorus recovery (14)
- Recycling (14)
- Microbiologically influenced corrosion (13)
- PFAS (13)
- Per- and Polyfluoroalkyl substances (PFAS) (13)
- Raman spectroscopy (13)
- Fungus (12)
- Inks (12)
- Black fungi (11)
- Construction products (11)
- Disinfection (11)
- E. coli (11)
- Manuscripts (11)
- NAP-XPS (11)
- XANES spectroscopy (11)
- Antimicrobial coating (10)
- Biocide (10)
- Reverse glass painting (10)
- Soil (10)
- Archaea (9)
- Cascade impactor (9)
- DRIFTS (9)
- Genetics (9)
- Knufia petricola (9)
- Manuscript (9)
- Microbiology (9)
- Persistence (9)
- Resistance (9)
- Standardization (9)
- Termite (9)
- Wastewater (9)
- Aerosol (8)
- Circular economy (8)
- Ecotoxicity (8)
- Ectoine (8)
- Fertilizer (8)
- Fungi (8)
- Geosynthetics (8)
- Indoor air quality (8)
- Non-destructive testing (8)
- Non-invasive analysis (8)
- TXRF (8)
- Volatile organic compounds (8)
- X-ray absorption near-edge structure (XANES) spectroscopy (8)
- Combustion ion chromatography (7)
- Coptic (7)
- Horizontal gene transfer HGT (7)
- Laser-induced periodic surface structures (LIPSS) (7)
- Melanin (7)
- Nanomaterial (7)
- Papyrus (7)
- Reference material (7)
- Resistance evolution (7)
- Risk assessment (7)
- Termites (7)
- Tolerance (7)
- Weathering (7)
- Antibiotics (6)
- BOFS (6)
- Bacterial adhesion (6)
- Biocide tolerance (6)
- Cultural heritage (6)
- DHN melanin (6)
- Dead Sea Scrolls (6)
- Emission (6)
- Fertilzer (6)
- Glutaraldehyde (6)
- Horizontal gene transfer (6)
- Hydraulic reactivity (6)
- ISO 16000-6 (6)
- Pathogen (6)
- Pigment (6)
- Remediation (6)
- Scandium (6)
- Thermal desorption (6)
- Wood protection (6)
- Alginate (5)
- Antimony (5)
- Bio-weathering (5)
- Biofilm formation (5)
- Cross-resistance (5)
- Degradation (5)
- Emission test chamber (5)
- Environmental Simulation (5)
- Gas chromatography (5)
- Ground water (5)
- Heterogeneity (5)
- Immunity (5)
- Incineration bottom ash (5)
- Ink analyses (5)
- Iron-gall ink (5)
- Korrosion (5)
- Methanogen (5)
- Mutation rate (5)
- Nanomaterials (5)
- Nanoparticle (5)
- Olivine (5)
- Parchment (5)
- Pigments (5)
- Portland Cement (5)
- Prüfrichtlinie (5)
- Pyrometallurgy (5)
- Reflectography (5)
- Sc-ICP-ToF-MS (5)
- Sewage sludge ash (5)
- Single cell analysis (5)
- Spectroscopy (5)
- Standardisation (5)
- Test guideline (5)
- Ultrafine particles (5)
- XANES (5)
- XPS (5)
- Zinc (5)
- ATR (4)
- Air quality monitoring (4)
- Alite (4)
- Analytical method (4)
- Anobium punctatum (4)
- Antimicrobial surfaces (4)
- Antimicrobials (4)
- Biocorrosion (4)
- Carbon steel (4)
- Corrosion products (4)
- Diffusive gradients in thin films (DGT) (4)
- EN 16516 (4)
- Electric arc furnace dust (4)
- Emission reference materials (4)
- Environmental evaluation (4)
- Geotextiles (4)
- Guideline (4)
- Gypsum (4)
- Humboldt Codices (4)
- ICP-MS (4)
- Ink analysis (4)
- Light (4)
- Lysimeter (4)
- Method development (4)
- Microcolonial fungi (4)
- Middle Ages (4)
- NanoSIMS (4)
- Nanoparticles (4)
- Nitrogen (4)
- Particles (4)
- Passive sampling (4)
- Polyethylene (4)
- Polyglycerol (4)
- Raman Spectroscopy (4)
- Red Mud (4)
- Reference materials (4)
- Round robin test (4)
- Steelmaking slag (4)
- Tantalum (4)
- Thermal treatment (4)
- Tineola bisselliella (4)
- Transformation (4)
- UFP (4)
- VVOCs (4)
- Virus (4)
- 3D printing (3)
- Affinity chromatography (3)
- Antibodies (3)
- Antimicrobial (3)
- Architecture (3)
- BEMMA (3)
- Bauxite Residue (3)
- Biodeterioration (3)
- Bioinformatics (3)
- Black fungus (3)
- Blast furnace sludge (3)
- Cairo Genizah (3)
- Carbon Fibers (3)
- Carbon steel corrosion (3)
- Chamber test (3)
- Chemical analysis (3)
- Chemical durability (3)
- Combustion Ion Chromatography (3)
- Combustion ion chromatography (CIC) (3)
- DNA (3)
- Design of experiments (3)
- Diffusive Gradients in thin films (DGT) (3)
- Diffusive gradients in thin-films (DGT) (3)
- Drawings (3)
- ESEM (3)
- Electron microscopy (3)
- Element mass concentration (3)
- Emerging (3)
- Emission reference material (3)
- Emissions (3)
- Environmental simulation (3)
- Extracellular polymeric substances (3)
- Extractable organically bound fluorine (EOF) (3)
- Extremotolerance (3)
- FFF-3D-Printer (3)
- FIB/SEM (3)
- Flow Model (3)
- Fluorescence (3)
- Genomics (3)
- Groundwater (3)
- Gut microbiota (3)
- HP14 (3)
- Halomonas elongata (3)
- Herculaneum (3)
- High resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) (3)
- Immune gene family (3)
- In-situ analysis (3)
- Interlaboratory comparison (3)
- Ir DNA staining approach (3)
- LIPSS (3)
- Laser processing (3)
- Manuscript studies (3)
- Material science (3)
- Materials emissions test (3)
- Mechanochemical treatment (3)
- Metabolism (3)
- Methanogen-induced microbiologically influenced corrosion (3)
- Microbiological influenced corrosion MIC (3)
- Microplastics (3)
- Mixed ink (3)
- Modelling (3)
- Modelling studies (3)
- Non destructive analytical techniques (3)
- Non-destructiv testing (3)
- Odour (3)
- Osmoadaptation (3)
- Particle size distribution (3)
- Perceived Intensity (3)
- Persian manuscripts (3)
- Phenotypic diversity (3)
- Phosphorus fertilizer (3)
- Quality assurance (3)
- Raman (3)
- Recovery (3)
- Recycling fertilizer (3)
- Recycling materials (3)
- Renewable Energy, Sustainability and the Environment (3)
- Rock-inhabiting fungus (3)
- SC-ICP-ToF-MS (3)
- Secondary building materials (3)
- Selective chlorination (3)
- Single cell (3)
- Size (3)
- Social (3)
- Stress tolerance (3)
- Struvite (3)
- Sulfate reducing bacteria (3)
- Symbiosis (3)
- UV radiation (3)
- VOC-emission (3)
- VVOC (3)
- Virulence (3)
- Waste management (3)
- Waste treatment (3)
- Wood Protection (3)
- X-ray diffraction (3)
- XRF analysis (3)
- 3D inspection (2)
- Additive Manufacturing (2)
- Additive Manufacturing (AM) (2)
- Adipokinetic hormone (2)
- Adipokinetic hormone receptor (2)
- Adsorbable organically bound fluorine (AOF) (2)
- Aerosol measurements (2)
- Agronomic performance (2)
- Air exchange rate (2)
- Air pollution (2)
- Air sampling (2)
- Aluminium (2)
- Ambient aerosols (2)
- Ammonium (2)
- Analytical methods (2)
- Anoxia (2)
- Antagonism (2)
- Antibiotic resisitance (2)
- Antiquity (2)
- Apanteles carpatus (2)
- Arabic Recipes (2)
- Artificial ageing (2)
- AshDec (2)
- Astrobiology (2)
- Atomic and Molecular Physics and Optics (2)
- Bacterial adhesion tests (2)
- Bacterial attachment (2)
- Bagasse (2)
- Baryscapus tineivorus (2)
- Bassanite (2)
- Bauprodukte (2)
- Bee (2)
- Biodiversity (2)
- Biofilm growth (2)
- Biofouling (2)
- Biogenic weathering (2)
- Biological pest control (2)
- Bioreceptivity (2)
- Biosynthesis (2)
- Biotechnology (2)
- Blattodea (2)
- Botrytis cinerea (2)
- Brown-rot fungi (2)
- Building and Construction (2)
- CDW processing (2)
- CFK (2)
- CO2 assisted impregnation (2)
- CRISPR/Cas9 (2)
- CSMC (2)
- Cabonfasern (2)
- Calcium alkali phosphate (2)
- Calcium silicate (2)
- Calcium sulfate (2)
- Cannibalism (2)
- Capsules (2)
- Carbide formation (2)
- Carbon feeding (2)
- Carbon ink (2)
- Chemical characterization (2)
- Chinese paper (2)
- Chromium (2)
- Circular Economy (2)
- Clinker substitute (2)
- Coastal protection (2)
- Cockroach (2)
- Colourants (2)
- Compatible solute (2)
- Comsumer good samples (2)
- Concrete (2)
- Condensed Matter Physics (2)
- Conservation (2)
- Consumer products (2)
- Contamination (2)
- Corynetes caeruleus (2)
- Crystallization (2)
- DGT (2)
- Density separation (2)
- Deponie (2)
- Desinfectant (2)
- Diffusive sampling (2)
- Disease (2)
- Disinfectants (2)
- Dry treatment (2)
- Dyes (2)
- E.coli (2)
- Electric Arc Furnace (2)
- Elektroofenstaub (2)
- Emission chamber (2)
- Emission testing (2)
- Emissionen (2)
- Energy Engineering and Power Technology (2)
- Entomopathogen (2)
- Environment (2)
- Environmental condition (2)
- European standard (2)
- Eusociality (2)
- FEM model (2)
- Flow system (2)
- Fluoride (2)
- Formaldehyde (2)
- Forsterite (2)
- Fuel Technology (2)
- Fume (2)
- Fungal biofilms (2)
- Genome sequence (2)
- Geogitter (2)
- Geokunststoffe (2)
- Geruch (2)
- Gichtgasschlamm (2)
- Glass (2)
- Glass scanning (2)
- Group defence (2)
- Gypsum recycling (2)
- HAXPES (2)
- Halomonas CRISPR Ectoine (2)
- Halophile (2)
- Hazard properties (2)
- Heavy metal removal (2)
- Hi-Tension (2)
- Hydrogen (2)
- In situ (2)
- Infrared spectroscopy (2)
- Ink composition (2)
- Inkwells (2)
- Insect biotechnology (2)
- Interdisciplinary (2)
- Interdisciplinary approach (2)
- Iron (2)
- Iron oxide nanoparticles (2)
- Isoptera (2)
- Keratin (2)
- Knufia (2)
- Korynetes caeruleus (2)
- Lapis lazuli (2)
- Laser Powder Bed Fusion (L-PBF) (2)
- Laser-induced breakdown spectroscopy (2)
- Leaching control mechanisms (2)
- Leaching of waste materials (2)
- Leaching tests (2)
- Leather (2)
- Life history data (2)
- Loading factor (2)
- Low melting (2)
- MOF (2)
- MSWI bottom ash (2)
- Magnesium (2)
- Marble (2)
- Marine littering (2)
- Material emissions (2)
- Mechanochemistry (2)
- Melting experiments (2)
- Metabolomics (2)
- Micro plastic (2)
- Micro-XRF (2)
- Microbial (2)
- Microbiologically influenced corrosion (MIC) (2)
- Microbiome (2)
- Microbiota (2)
- Microorganism (2)
- Micropatterning (2)
- Microplastic (2)
- Mikrobiell beeinflusste Korrosion (2)
- Model (2)
- Museum (2)
- Museum Pests (2)
- Nano particle (2)
- Nanopartikel (2)
- Neuropeptide (2)
- Nitrification inhibitor (2)
- Non invasive analysis (2)
- Nosema ceranae (2)
- Nutrient (2)
- Optics (2)
- Osmia bicornis (2)
- PGAA (2)
- PIXE (2)
- Particle gas emission (2)
- Particle size (2)
- Particle size distributuion (2)
- Particulate emission (2)
- Per- and polyfluorinated alkyl substances (PFASs) (2)
- Per- and polyfluoroalkyl substances (PFAS) (2)
- Perceived intensity (2)
- Permeable reactive barriers (2)
- Persister cells (2)
- Phopshorus recovery (2)
- Pigment analyses (2)
- Pigment identification (2)
- Plant pathogen (2)
- Plume (2)
- Pollutant (2)
- Pollutants (2)
- Provenance studies (2)
- Pseudomonas aeruginosa (2)
- Purification (2)
- Reactive oxygen species (2)
- Recycling fertiliser (2)
- Recycling fertilisers (2)
- Reduction process (2)
- Reductive amination (2)
- Reference method (2)
- Rembrandt (2)
- Ressourcenrückgewinnung (2)
- Restoration and conservation (2)
- Risk assesment (2)
- Robustness studies (2)
- Sapphire (2)
- Scattering (2)
- Sewage sludge ordinance (2)
- Shale (2)
- Size distribution (2)
- Size resolved chemical composition (2)
- Social immunity (2)
- Soil P species (2)
- Soil-like material (2)
- Solar panel (2)
- Solubility (2)
- Sorption (2)
- Spatter (2)
- Stained glass (2)
- Steelmaking (2)
- Stress (2)
- Structured light scanning (2)
- Subaerial biofilm (2)
- Subaerial biofilms (2)
- Substance release (2)
- Sustainability (2)
- Synchrotron (2)
- Synthetic organic pigments (2)
- Termite phylogeny (2)
- Test Guideline (2)
- Testguideline (2)
- Thermal extraction (2)
- Thermochemical treatment (2)
- Time resolved chemical composition (2)
- Total reflection X-ray spectroscopy (2)
- Transcriptomics (2)
- Tricalcium-silicate (2)
- UV-irradiation (2)
- Vanadium (2)
- Virology (2)
- Waste-to-energy (2)
- Wild bees (2)
- Wooden toys (2)
- Writing inks (2)
- X-Ray fluorescence analyses (2)
- X-ray adsorption near-edge structure (XANES) spectroscopy (2)
- Zink (2)
- genetics (2)
- melanin (2)
- (Semi)arid to humid-temperate natural ecosys (1)
- 13CO2 pulse labeling (1)
- 13th century (1)
- 16S rRNA gene (1)
- 2D nanomaterials (1)
- 3D Printing (1)
- 3D printer (1)
- A Greek palimpsest (1)
- A key interface (1)
- A-DNA conformation (1)
- AEROMET II (1)
- AEROMET project (1)
- AMR (1)
- ASAP-MS (1)
- ATR-FTIR (1)
- Academia (1)
- Accelerated aging (1)
- Accuracy (1)
- Acidobacteria (1)
- Adaptation (1)
- Adaption (1)
- Additive manufacturing (1)
- Advanced groups of termites (1)
- Aerodynamic levitation (1)
- Aerosol element alanysis (1)
- Aerosol element mass concentration (1)
- Aerosol gravimetry (1)
- Aerosol measurement instruments (1)
- Aerosol spectroscopy (1)
- Aerosols (1)
- Aerosolsensor (1)
- Affinity extraction (1)
- Affinity support (1)
- Ag-LDI-MS (1)
- AgBB Bewertung (1)
- Agarose (1)
- Ageing (1)
- Aging (1)
- Aging test (1)
- Aging tests (1)
- Agricultural mycology (1)
- Air analysis (1)
- Air pollution control (1)
- Air quality (1)
- Airborne Particles (1)
- Alexander von Humboldt (1)
- Alite hydraulic reactivity (1)
- Alkali zinc borate glass (1)
- Alkylating agents (1)
- Aluminum (1)
- Aluminum oxide (1)
- Ambient aerosol (1)
- Ambient air (1)
- Ambient air pollution (1)
- Amino acid analysis (1)
- Amphiphilic polymer (1)
- Amplicon sequencing (1)
- Anaerobic pathways (1)
- Analytical Chemistry (1)
- Analytical chemistry (1)
- Analytical screening techniques (1)
- Analytical standards (1)
- Ancient INKS (1)
- Ancient document production (1)
- Animal immune system (1)
- Anodization (1)
- Anti-microbial effects (1)
- Antiadhesive surfaces (1)
- Antibacterial (1)
- Antibacterial coatings (1)
- Antibacterial polymer (1)
- Antibacterial surfaces (1)
- Antibiotic (1)
- Antibiotic resistance (1)
- Antibody purification (1)
- Antifouling (1)
- Antimicrobial Resistance (1)
- Antimicrobial materials (1)
- Antimicrobial resistances (1)
- Antimicrobial test (1)
- Antimicrobial testing (1)
- Antimony black (stibnite) (1)
- Antiseptic agents (1)
- Aquatic fungi (1)
- Aqueous synthesis (1)
- Arabic recipes (1)
- Arbuscular mycorrhiza (1)
- Archaeological provenance (1)
- Archaeometric studies (1)
- Aromatic amino acid analysis AAAA (1)
- Aromatic amino acid analysis aaaa (1)
- Artificial weathering (1)
- Ascomycetes (1)
- Ascosphaera apis (1)
- Ashdec (1)
- Aspergillus (1)
- Aspergillus flavus (1)
- Assessment (1)
- Atomic force microscopy (1)
- Autoclave tests (1)
- Automated analysis (1)
- BESSY (1)
- BFR (1)
- BODIPY (1)
- BODIPY dye (1)
- BSA (1)
- BTEX (1)
- Bacillus subtilis (1)
- Bacteria repellent surfaces (1)
- Bacteria-repellent surfaces (1)
- Bacterial cell cycle (1)
- Bacterial growth (1)
- Bacterial infection (1)
- Bacterial second messenger (1)
- Baltic Sea (1)
- Bankia sp (1)
- Basidiomycetes (1)
- Basin (1)
- Batch tests (1)
- Bathyarchaeia (1)
- Bauxite residue (1)
- Bawit (1)
- Bee diseases (1)
- Bee health (1)
- Bees (1)
- Behavioural mechanisms (1)
- Beneficial microbes (1)
- Beschichtung (1)
- Beständigkeit (1)
- Bio-based insulation (1)
- Bio-receptive (1)
- Bioactive glass (1)
- Bioavailability (1)
- Bioceramics (1)
- Biocides in the environment (1)
- Bioconjugation (1)
- Biodegradation (1)
- Biodeterioration and biodegradation (1)
- Biofilm quantification (1)
- Bioilm (1)
- Bioinformatics virology viruses software (1)
- Biokorrosion (1)
- Biological Control (1)
- Biological control (1)
- Biologically induced mineral weathering (1)
- Biomimetic (1)
- Bioseparation (1)
- Biosphere (1)
- Biosphere-technosphere interaction (1)
- Biotests (1)
- Biotic environment (1)
- Biphasic growth (1)
- Black Ink (1)
- Black microcolonial fungi (1)
- Black writing ink (1)
- Blast-furnace sludge (1)
- Blue Angel ecolabel (1)
- Bodenbelag (1)
- Book production (1)
- Botrytis (1)
- Bovine serum albumin (1)
- Building Material (1)
- Building material (1)
- Building materials (1)
- Building product (1)
- Building products (1)
- Built environment (1)
- Bushveld Complex (1)
- Byzantine manuscript (1)
- C-di-GMP (1)
- CCQM (1)
- CEC-L-103 (1)
- CFRP (1)
- CHC (1)
- CIC (1)
- COST Action (1)
- COST action CA15114 AMICI (1)
- COVID (1)
- CPC calibration (1)
- CRISPR dCas9 (1)
- CRM (1)
- CaNaPO4 (1)
- Calcareous deposits (1)
- Calcium carbonate (1)
- Calibration (1)
- Calibration transfer (1)
- Carbon Fibre (1)
- Carolingian (1)
- Carotenoids (1)
- Carrier (1)
- Cascade impector (1)
- Cast iron (1)
- Cathodic protection (1)
- Cell appendages (1)
- Cell studies (1)
- Cell-envelope (1)
- Cellulose ether (1)
- Cellulose synthase (1)
- Cerium oxide (1)
- Chamber measurement (1)
- Chamber-test (1)
- Characterisation (1)
- Characterization (1)
- Chemical composition (1)
- Chemical ecology (1)
- Chemical extraction (1)
- Chemical extraction methods (1)
- Chemical recycling (1)
- Chemicals (1)
- Chicken manure (1)
- Chicken manure ash (1)
- Chilean Coastal Cordillera (1)
- Chinese Paper (1)
- Chlorination (1)
- Chlorine (1)
- Chromitites (1)
- Clean steel (1)
- Cleridae (1)
- Climate gradient (1)
- Climate responsive materials (1)
- Cloning vectors (1)
- Close proximity to colonies (1)
- Co-combustion (1)
- Cobalt (1)
- Cockroaches (1)
- Codex (1)
- Codex Miscellaneus (1)
- Codicology (1)
- Cognitive performance (1)
- Coleoptera (1)
- Colorants (1)
- Colored glasses (1)
- Colouring (1)
- Combustion and gasification (1)
- Community composition (1)
- Community-level interactions (1)
- Comparison (1)
- Concept (1)
- Conditioning layer (1)
- Confocal microscopy (1)
- Coniophora puteana (1)
- Conjugate (1)
- Conjugation (1)
- Constantinomyces (1)
- Construction Products (1)
- Construction and demolition waste (1)
- Construction materials (1)
- Construction product (1)
- Construction products regulation (CPR) (1)
- Consumer article (1)
- Consumer articles (1)
- Contaminant transfer (1)
- Contraction (1)
- Control (1)
- Controllable gene expression (1)
- Controlled atmosphere (1)
- Controlled release fertilisers (1)
- Copper (1)
- Copper-based wood preservatives (1)
- Coptic manuscripts (1)
- Coptic papyri (1)
- Coptic studies (1)
- Coptotermes (1)
- Core microbiome (1)
- Core/shell nanoparticle (1)
- Corona (1)
- Corrosion product (1)
- Corundum (1)
- Cribellate spiders (1)
- Crispr-Cas9 (1)
- Crispr/Cas9 (1)
- Critical raw materials (1)
- Cross-feeding (1)
- Cross-sectioning (1)
- Cryo XPS (1)
- Cryptoendolithic black fungus (1)
- Cryptoendolithism (1)
- Crystalline phase identification (1)
- CuNPs (1)
- Cubical shape (1)
- Cultural Entomology (1)
- Cultural Heritage (1)
- Culuative energy demand (1)
- Cupriavidus campinensis (1)
- Cuticular hydrocarbons (1)
- Cyanobacteria (1)
- DNA barcode (1)
- DNA polymerase (1)
- DSLT (1)
- DSM 5009 (1)
- Damage repair (1)
- De novo assembly (1)
- Decomposition point (1)
- Degradable polymer (1)
- Dendrimer (1)
- Denitrification (1)
- Deponiebau (1)
- Desert ecology (1)
- Desiccation (1)
- Deterioration (1)
- Developing building materials (1)
- Development (1)
- Dielectric heating (1)
- Dietary adaptation (1)
- Differential expression (1)
- Differential gene expression analysis (1)
- Diffractive gratings (1)
- Diffusive Gradients in Thin-films (DGT) (1)
- Digitalisation (1)
- Direct laser writing (1)
- Direct material input (1)
- Disinfection Fuel (1)
- Dispay case (1)
- Dispersion of carbon pigments (1)
- Display case (1)
- Disposal (1)
- Diversity (1)
- Dothideomycetes (1)
- Downstream processing (1)
- Draft Genome (1)
- Drawing (1)
- Driving rain (1)
- Drywood termite (1)
- DsRNA (1)
- Durability (1)
- Dye (1)
- Dyes and pigments (1)
- Dynamic calibration gas mixtures (1)
- Dynamic surface leaching test (1)
- E$volution (1)
- EAF slags (1)
- EDX Analysis (1)
- EN 717-3 (1)
- EOF (1)
- EOF/AOF (1)
- EU EMPIR (1)
- EU regulations (1)
- Early european inks (1)
- Earthen building materials (1)
- Eco-efficiency analysis (1)
- Ecology (1)
- Ecotoxicity testing (1)
- Ecotoxicity tests (1)
- Ecotoxicological tests (1)
- Ecotoxixity (1)
- Edible insects (1)
- Effective uptake rate (1)
- Efficacy (1)
- Efflux (1)
- Egypt (1)
- Electric arc furnace (EAF) slags (1)
- Electric arc furnace slags (1)
- Electrochemical remediation (1)
- Electronic (1)
- Electronic Lab Notebook (ELN) (1)
- Element analysis (1)
- Element mass concetration (1)
- Elemental aerosol analysis (1)
- Elemental composition (1)
- Eluates (1)
- Emerging Contaminants (1)
- Emission Test Chamber (1)
- Emission Testing (1)
- Emission chamber testing (1)
- Emission chambers (1)
- Emission test chamber procedure (1)
- Emission test method (1)
- Emissions of hazardous gases (1)
- Emisson testing (1)
- Enamel colors (1)
- Enamels (1)
- Entomopathogenic Fungus (1)
- Entropy (1)
- Environmental Chemistry (1)
- Environmental Engineering (1)
- Environmental assessment (1)
- Environmental conditions (1)
- Environmental friendly (1)
- Environmental impact (1)
- Environmental simulations (1)
- Epidemal layer (1)
- Erfurt (1)
- Essential oils (1)
- European research area (1)
- Eurotiomycetes (1)
- Exergy (1)
- Exocrine gland (1)
- Expansion (1)
- Experimental evolution (1)
- Exposure (1)
- Exposure risk (1)
- External (1)
- Extracellular enzymes (1)
- Extracellular pH (1)
- Extractable organic fluorine (1)
- Extraction (1)
- Extreme environments (1)
- Extremophile (1)
- Extremophiles (1)
- Extremophilic fungi (1)
- F pili (1)
- FAT class concept (1)
- FFF-3D printer (1)
- FFF-3D printing (1)
- FFF-filament (1)
- FFF-printing (1)
- FT-Raman (1)
- FTIR (1)
- FTIR spectroscopy (1)
- FactSage calculations (1)
- FactSageTM calculations (1)
- Fakes (1)
- Family archives (1)
- Faraday cup aerosol electrometer (1)
- Fatigue (1)
- Façade (1)
- Feeding behaviour (1)
- Femtosecond laser processing (1)
- Fenton-like reaction (1)
- Fiber (1)
- Fibre (1)
- Fibre analysis (1)
- Filament comparison (1)
- Fire-retardant paint (1)
- Flask method (1)
- Flexible shadow masks (1)
- Flow chamber system (1)
- Flow-System (1)
- Flow-system (1)
- Fluor XANES (1)
- Fluorescence spectroscopy (1)
- Fluorescent microscopy (1)
- Fluorescent proteins (1)
- Fluoride nanoparticles (1)
- Fluorides (1)
- Fluorolytic sol-gel synthesis (1)
- Fluorolytic sol−gel (1)
- Fluorometric sensing (1)
- Food (1)
- Food fermentation (1)
- Food safety (1)
- Force distance curve (1)
- Forest fires (1)
- Forest soils (1)
- Forgery (1)
- Formation enthalpy (1)
- Foward genetics (1)
- Fractal structure (1)
- Fractional factorial (1)
- Fragmented manuscripts (1)
- Fuel sorption (1)
- Functionalized graphene (1)
- Fungal decay (1)
- Fungal stress mechanisms and responses (1)
- Fungicidal property (1)
- Fungiculture (1)
- Fusarium (1)
- GAeF (1)
- GC-FID (1)
- GC-MS (1)
- GDL (1)
- GNBP-2 (1)
- Gas analysis (1)
- Gas chromatography - mass spectrometry (GC-MS) (1)
- Gas sensing (1)
- Gas storage (1)
- Gene expression (1)
- Gene network (1)
- General Chemistry (1)
- General Environmental Science (1)
- General Materials Science (1)
- General Medicine (1)
- Genetic engineering (1)
- Genetic tools (1)
- Genome (1)
- Genome editing (1)
- Geobiology (1)
- Geological formation (1)
- Geology (1)
- Geomembranes (1)
- Geruchsmessung (1)
- Giulio Romano (1)
- Glass paints (1)
- Global radiation (1)
- Gold (1)
- Gothic incursions (1)
- Granulat (1)
- Graphene (1)
- Graphene–bacteria interaction (1)
- Gray mold fungus (1)
- Green facades (1)
- Green pesticide (1)
- Greenhouse gas accounting (1)
- Greenhouse gas balance (1)
- Greenhouse gas mitigation (1)
- Grouts (1)
- Growth-rate homeostasis (1)
- Gut symbionts (1)
- Gypsum fiberboards and synthetic gypsum (1)
- Gypsum plasterboards (1)
- Gypsum waste (1)
- HI-Tension (1)
- HR-CS-GFMAS (1)
- Halogenation (1)
- Halophilic (1)
- Halophilic bacteria (1)
- Hazardous waste (1)
- Haze Samples (1)
- Hazenite (1)
- Headspace GC-MS (1)
- Health, Toxicology and Mutagenesis (1)
- Healthcare (1)
- Heat capacity (1)
- Heat maps (1)
- Heavy metal free (1)
- Heavy metals (1)
- Hebrew studies (1)
- Hellenistic (1)
- Herbaspirillum seropedicae (1)
- Herculaneum papyri (1)
- Hermopolis (1)
- Herteogeneous phenotypes (1)
- Heterologous expression (1)
- High density polyethylene (1)
- High salinity (1)
- Historic buildings (1)
- Historic ink (1)
- History of Art (1)
- Holy Family (1)
- Holzschutzmittel (1)
- Honey bee (1)
- Honeybee (1)
- Hospital premises (1)
- Host and symbiont ecology (1)
- Host immunity (1)
- Household waste (1)
- Human plasma (1)
- Hydration products (1)
- Hydraulic engineering (1)
- Hydrogen permeation (1)
- Hydrogen storage (1)
- Hydrogenasen (1)
- Hydrophobic interaction (1)
- Hygienic behavior (1)
- Hylotrupes bajulus (1)
- Hylotrupes bajulus, Anobium punctatum, natural durability, tropical wood, native wood. (1)
- Hyperarid (1)
- Hyperbranched polymer (1)
- Hypermutation (1)
- Hypopharynx (1)
- IAQ (1)
- ICP-OES (1)
- IEQ (1)
- IPM in museums (1)
- IR spectroscopy (1)
- ISO 22196 (1)
- ISO REMCO (1)
- ISO/TC 229 Nanotechnologies (1)
- ISO22196 (1)
- ITS region (1)
- Idiopathic environmental intolerance (1)
- Igg (1)
- Illness-induced anorexia (1)
- Illuminated manuscripts (1)
- Immune gene prediction (1)
- ImmunoDB (1)
- Immunoglobulins (1)
- Immunoprecipitation (1)
- Implants (1)
- In situ synchrotron x-ray diffraction (1)
- In-situ Process Monitoring (1)
- In-vivo mutagenesis (1)
- Incubated soil/fertilizer mixtures (1)
- Indirect photolysis (1)
- Indoor Air Quality (1)
- Indoor Air: Adsorbent performance (1)
- Indoor Products (1)
- Indoor air (1)
- Indoor emission (1)
- Indoor mycobiome (1)
- Industrial and Manufacturing Engineering (1)
- Industrial applications (1)
- Industrial mycology (1)
- Infecting a number of insects, (1)
- Infections (1)
- Infrared thermography (1)
- Initial attachment (1)
- Ink corrosion (1)
- Ink fingerprint (1)
- Ink terminology (1)
- Insect evolution (1)
- Insecticide (1)
- Instrumentation (1)
- Integrated Museum Pest Management (IMPM) (1)
- Inter-comparison (1)
- Inter-lab comparison (1)
- Inter-laboratory test (1)
- Intercomparison (1)
- Interdisciplinarity (1)
- Internal pores (1)
- Intraparticle diffusion (1)
- Intumescent coating (1)
- Iodine (1)
- Ionic liquid (1)
- Ionizing radiation (1)
- Iron gall ink (1)
- Iron making (1)
- Iron oxide (1)
- Iron scrap (1)
- Isotopes (1)
- Issues (1)
- Jewish cultures (1)
- Jig (1)
- Joint grouts (1)
- Knock-out mutant (1)
- Kunststoffdichtungsbahnen (1)
- LC-MS/MS (1)
- LCA (1)
- LCC (1)
- LIBS (1)
- Laboratory breeding (1)
- Labrum (1)
- Laccase (1)
- Lake Cadagno (1)
- Landfill (1)
- Landfill lining (1)
- Laser Printer (1)
- Laser printer emission (1)
- Laser structuring (1)
- Laser-induced nanostructures (1)
- Laser-induced pariodic surface structures (1)
- Laser-induced periodic surface structueres (LIPPS) (1)
- Laser-modified surface (1)
- Layer-by-Layer (1)
- Lead (1)
- Lead books (1)
- Leonardo da Vinci (1)
- Lfe cycle assessment (1)
- Library pests (1)
- Lifetime (1)
- Light regulation (1)
- Light sensing (1)
- Light-induced stress (1)
- Lightning talk (1)
- Lightweighting (1)
- Lignocellulose (1)
- Limit values (1)
- Limitations (1)
- Limnoria spp (1)
- Linker (1)
- Low alloy steel (1)
- Low cost aerosol PM sensor (1)
- Low melting glasses (1)
- Low-molecular-weight organic substances (1)
- Low-tech approach (1)
- Luftgüte (1)
- Lysimeter, Antimony (1)
- MDG ICP-ToF-MS (1)
- MIC Island (1)
- MIC projekt (1)
- MSWI Bottom Ash (1)
- MSWI fly ash (1)
- Major transition (1)
- Manuscript making (1)
- Map production and publishing (1)
- Maps and colours (1)
- Marek's Disease Virus (1)
- Marek's virus (1)
- Marine borers (1)
- Market surveillance (1)
- Mask fabrication (1)
- Mass spectrometry (1)
- Mass spectroscopy (1)
- Material Analysis (1)
- Material analysis (1)
- Material degradation (1)
- Material emissions testing (1)
- Material recycling (1)
- Material surface colonisation (1)
- Materials (1)
- Materials Chemistry (1)
- Materials emissions testing (1)
- Materials flow (1)
- Mathematical analysis (1)
- Mathematical modelling (1)
- Mechanische Stabilität (1)
- Mechanisms of pathogenesis (1)
- Mechanosensitive channel (1)
- Medical mycology (1)
- Medieval glasses (1)
- Medieval-stained glass (1)
- Melanin Adhesion (1)
- Melanins (1)
- Melting point (1)
- Melting temperature (1)
- Metabolic engineering (1)
- Metabolic flux analysis (1)
- Metabolic modeling (1)
- Metadata (1)
- Metal organic frameworks (1)
- Metal recovery (1)
- Metal reducing bacteria (1)
- Metallic silver precipitates (1)
- Metalls (1)
- Metals (1)
- Metals and Alloys (1)
- Metarhizium (1)
- Metarhizium robertsii DSM 1490 (1)
- Methane (1)
- Methanogenesis (1)
- Methods of scientific analysis (1)
- Microbe (1)
- Microbial abundance (1)
- Microbial adhesions (1)
- Microbial communities (1)
- Microbial community modelling (1)
- Microbial simulation, (1)
- Microbial survival mechanisms (1)
- Microbially Induced Corrosion (1)
- Microbially induced carbonate precipitation (MICP) (1)
- Microbiologically Influrenced Corrosion (MIC) (1)
- Microchamber (1)
- Microdroplet generator (1)
- Microfluidics (1)
- Micromonospora aurantiaca (1)
- Microorganisms (1)
- Microwaves (1)
- Migration (1)
- Mikrobiell (1)
- Mikroplastik (1)
- Millipedes (1)
- Mineral (1)
- Mineral weathering (1)
- Mining (1)
- Mircobially influcenced corrosion (1)
- Mixed Inks (1)
- Mixture toxicity (1)
- Mobile anodisation (1)
- Mobile application (1)
- Model aerosols (1)
- Model organism (1)
- Modeling (1)
- Modern painting (1)
- Modified mycotoxins (1)
- Moisture (1)
- Moisture performance (1)
- Molecular (1)
- Molecular Organic Frameworks (1)
- Molecular clock (1)
- Molecular identification (1)
- Molybdenum (1)
- Monoterpene (1)
- Moriscos (1)
- MscS (1)
- Mud volcanoe fluids (1)
- Multi-resistant bacteria (1)
- Multi-scale study (1)
- Multicellularity (1)
- Multidisciplinary (1)
- Multilocus phylogeny (1)
- Multiple Displacement Amplification (1)
- Multiple chemical sensitivity (1)
- Multiple lines of evidence (1)
- Multiport (1)
- Municipal sewage sludge (1)
- Municipal solid waste (1)
- Museum insect pest (1)
- Museum pests (1)
- Mussel-inspired coating (1)
- Mussel-inspired materials (1)
- Mutagenesis (1)
- MySpot (1)
- Mycotoxin (1)
- Mycotoxins (1)
- Müllverbrennung (1)
- N and K analog tracer (1)
- NDT (1)
- NFDI (1)
- NGS (1)
- NIR imaging (1)
- NIR reflectography (1)
- Nano CRM (1)
- Nano Particles (1)
- Nano characterization (1)
- Nano metal fluorides (1)
- Nano-Fourier-transform infrared spectroscopy (1)
- Nano-materials (1)
- Nano@BAM (1)
- Nanobiocide (1)
- Nanocarrier (1)
- Nanocoating (1)
- Nanoplattform (1)
- Nanopowder (1)
- Nanorods (1)
- Nanosensor (1)
- Natural abundance of 15N (1)
- Natural durability (1)
- Natural ecosystems (1)
- Natural products discovery (1)
- Near ambient pressure XPS (1)
- Near ambient x-ray photoelectron spectroscopy (1)
- Near-infrared refectography (1)
- New exocrine organ (1)
- Next generation sequencing (1)
- Nickel (1)
- Niobium (1)
- Nitrate (1)
- Nitrogen fixation (1)
- Nitrogen uptake (1)
- Nitrososphaerales (1)
- Nitrous oxide (1)
- Non-destructive Materials (1)
- Non-destructive test (1)
- Non-ferrous metals (1)
- Non-invasive (1)
- Non-invasive scientific methods (1)
- Non-vitriolic iron-gall inks (1)
- Nonspecific binding (NSB) (1)
- Nonvolatile (1)
- Nostoc (1)
- Nostoc punctiforme (1)
- Novel sample preparation techniques (1)
- Nuclear waste disposal (1)
- Nutrient acquisition (1)
- Nutrient cycles (1)
- Nutrient uplift and recyclin (1)
- Nährstoffe (1)
- OIT (1)
- Oddy test (1)
- Office machines (1)
- Oil (1)
- Oil and gas industry (1)
- Oil and gas reservoir (1)
- Oilfield (1)
- On-line analysis (1)
- One-step ionic liquids synthesis (1)
- Open data (1)
- Operating Procedure (1)
- Optical and Magnetic Materials (1)
- Optical properties (1)
- Ordinance on Contaminated Sites and Soil Protection (1)
- Organic contaminants (1)
- Organic phosphorus breakdown (1)
- Organo fluorine analysis (1)
- Osmophobic effect (1)
- Osmotic shock (1)
- Osteogenesis (1)
- Oxide melts (1)
- P sink method (1)
- P speciation (1)
- P-efficiency (1)
- P-recovery (1)
- P. Fluorescens (1)
- PAH (1)
- PAK (1)
- PE-HD (1)
- PFAS analysis (1)
- PFAS analytics (1)
- PM (1)
- PM monitors (1)
- PP (1)
- PS (1)
- PV modules (1)
- Painting (1)
- Paints (1)
- Palaeography (1)
- Palimpsest (1)
- Paper (1)
- Paper sizings (1)
- Paper tinting (1)
- Particle (1)
- Particle Size (1)
- Particle emission (1)
- Particle synthesis (1)
- Particulate emissions (1)
- Partikel (1)
- Partikeln (1)
- Parylene C (1)
- Pathogen spillover (1)
- Pathogen transmission (1)
- Pathogen virulence (1)
- Pentimenti (1)
- Peptide-derived components (1)
- Per- and polyfluorinated alkly substances (PFASs) (1)
- Perfluorierte Verbindungen (1)
- Perfluorocarboxylic acid (PFCA) (1)
- Performance (1)
- Performance comparison (1)
- Periodate oxidation (1)
- Permeability (1)
- Persian historical recipes (1)
- Persian manuscript (1)
- Pest control (1)
- Pesticides (1)
- Phase formation (1)
- Phase separation (1)
- Phase transformation (1)
- Phenotypic heterogeneity (1)
- Phenotypic variation (1)
- Phoshpor availability (1)
- Phosphate dynamics (1)
- Phosphate extractability and availability (1)
- Phosphonic acids (1)
- Phosphorous recovery (1)
- Phosphorus K-edge-XANES spectroscopy (1)
- Phosphorus availability (1)
- Phosphorus elimination (1)
- Phosphorus plant-availability (1)
- Phosphorus recycling (1)
- Phosphous recovery (1)
- Photocatalytic surfaces (1)
- Photodynamic therapy (1)
- Photometric P determination (1)
- Photonics (1)
- Photoperception (1)
- Photoreceptors (1)
- Phototrophic bacteria (1)
- Phototrophs (1)
- Phyllosphere (1)
- Physical and optical characteristics (1)
- Pilot comparison (1)
- Plant Experiment (1)
- Plant availability (1)
- Plant economic spectrum (1)
- Plant growth test (1)
- Plant-availability (1)
- Plasma (1)
- Plastic biofilm (1)
- Plastic degradation (1)
- Plastic pollution (1)
- Plastic waste (1)
- Platinum (1)
- Poficiency test (1)
- Pollution (1)
- Polydopamine (1)
- Polyelektrolyt (1)
- Polyethylene terephthalate (1)
- Polyfluorinated alcohol (PFOH) (1)
- Polyioinic liquid (1)
- Polymer (1)
- Polymer Matrix Composites (1)
- Polymer foils (1)
- Polymer-based products (1)
- Polymerase mutant (1)
- Polypropylene (1)
- Polystyrene (1)
- Polyurethanes (1)
- Porosity (1)
- Portrayal of St Joseph (1)
- Poster presentation (1)
- Pot experiment (1)
- Pot experiments (1)
- Potential toxic elements (1)
- Preferential binding (1)
- Preferential exclusion (1)
- Preservation (1)
- Probiotic-based vaccines (1)
- Probiotics (1)
- Process Metallurgy (1)
- Process control (1)
- Process development (1)
- Process monitoring (1)
- Process upscaling (1)
- Proficiency Test (1)
- Proficiency testing (1)
- Proofreading deficient (1)
- Prospective risk assessment (1)
- Protective glazing (1)
- Protein (1)
- Protein a (1)
- Protein hydrolysis (1)
- Protein immobilization (1)
- Protein quantification (1)
- Proteome (1)
- Proteomics (1)
- Pseudomonas (1)
- Pseudomonas fluorescens (1)
- Pseudomonas veronii (1)
- Ptinidae (1)
- Public Health, Environmental and Occupational Health (1)
- Push-out Test (1)
- Pyrolysis (1)
- QA/QC (1)
- Quality assurance/quality control (1)
- Quantum dot (1)
- Quasispecies (1)
- REACH (1)
- RNA extraction (1)
- RNA interference (1)
- RNA-Seq (1)
- RNA-Sequencing (1)
- RNAi (1)
- Radio waves (1)
- Radiocarbon (1)
- Radon (1)
- Radon exhalation (1)
- Raphael school (1)
- Reactor conditions (1)
- Real-time qPCR (1)
- Recipes (1)
- Recovery potential (1)
- Recovery rate (1)
- Recycled gypsum (1)
- Recycled sources (1)
- Red chalk (1)
- Red mud (1)
- Reduction (1)
- Reductive decomposition (1)
- Reductive defluorination (1)
- Reductive iron assimilation (1)
- Reference data (1)
- Reference nanoparticles (1)
- Reference organisms (1)
- Reference procedures (1)
- Reference samples (1)
- Regulation (1)
- Release kinetics (1)
- Research Data Infrastructure (1)
- Research Data Management (1)
- Resistance model (1)
- Resource Recovery (1)
- Resources (1)
- Reverse painting on glass (1)
- Reverse paintings on glass (1)
- Reworking (1)
- Rhenanite (1)
- Rhizopus (1)
- Rhizopus and Aspergillus oryzae (1)
- Rhizosphere (1)
- Rhizosphere effect (1)
- Rhizosphere processes (1)
- Rhodonia placenta (1)
- Rice (1)
- Road construction waste (1)
- Robustness validation (1)
- Rock biofilm (1)
- Rock leaching (1)
- Rock-inhabiting black fungi (1)
- Rock-inhabiting fungi (1)
- Root economics space (1)
- Rostral gland (1)
- Rround robin test (1)
- Ruthenium (1)
- SARS (1)
- SAXS (1)
- SCALE (1)
- SDS-PAGE (1)
- SEM (1)
- SEM micrography (1)
- SEM wood characterization (1)
- SEM-EDS (1)
- SERS (1)
- SIMS (1)
- SOP (1)
- SPE extraction (1)
- SRB (1)
- SVOC (1)
- Safety (1)
- Salts (1)
- Sample preparation (1)
- Sanierung (1)
- Sc recovery (1)
- Scanning micro-X-ray fluorescence (1)
- Scattering-type scanning near-field optical microscopy (s-SNOM) (1)
- Schwermetalle (1)
- Scribal corrections (1)
- Scythica Vindobonensia, (1)
- Secondary P-fertilizer (1)
- Secondary Recources (1)
- Secondary metabolism (1)
- Secondary metabolites (1)
- Secondary raw materials (1)
- Secondary resources (1)
- Sediment (1)
- Selection (1)
- Selective Chlorination (1)
- Selective quantification (1)
- Self-assembled monolayer (1)
- Self-assembled monolayer (SAM) (1)
- Self-assembled monolayers (SAM) (1)
- Semivolatile organic compounds (1)
- Sensors (1)
- Separate collection (1)
- Sequence annotation (1)
- Sequential extraction (1)
- Sets of archaeometric data (1)
- Sewage Sludge (1)
- Sewage Sludge Ashes (1)
- Sewage extraction (1)
- Sewage sludge ash (SSA) (1)
- Sewage sludge disposal (1)
- Sewage sludge incineration (1)
- Short crack propagation (1)
- Siderophore (1)
- Signal transduction (1)
- Silica and polystyrene nanoparticles (1)
- Silicate (1)
- Silicon carbide (1)
- Silver (1)
- Silver diffusion (1)
- Simulation (1)
- Simulation of materials degradation (1)
- Single cell microbiology (1)
- Sintering (1)
- Sixteenth-century painting technique (1)
- Size exclusion chromatography (1)
- Sizing (1)
- Small angle x-ray scattering (1)
- Smartphone (1)
- Social Immunity (1)
- Social insect (1)
- Social insects (1)
- Sociality (1)
- Software (1)
- Soil contact (1)
- Soil extraction (1)
- Soil incubation study (1)
- Soil-feeding habit (1)
- Soil-like materials (1)
- Soils (1)
- Solar panels (1)
- Solar parks (1)
- Soldier (1)
- Solid phase (1)
- Solid phase extraction (SPE) (1)
- Solid-liquid extraction (1)
- Solid-phase extraction (SPE) (1)
- Solitary bees (1)
- Solute excretion (1)
- Solvents (1)
- Solvolysis (1)
- Spectral imaging (1)
- Stained glass windows (1)
- Stained glasses (1)
- Stainless steel (1)
- Stakeholder (1)
- Standardized test and quantification procedure (1)
- Steelmaking residues (1)
- Stoichiometric homeostasis (1)
- Stone cultural heritage (1)
- Stop/flow experiments model (1)
- Strategy and Management (1)
- Stress conditions (1)
- Structural color (1)
- Sub-4nm particles (1)
- Subjective complaints (1)
- Subsocial (1)
- Subsoil nutrient tracing (1)
- Sugar cane bagasse (1)
- Sugarcane bagasse (1)
- Sum parameter (1)
- Sum parameter analyis (1)
- Sum parameter analysis (1)
- Superhydrophilic surface (1)
- Superhydrophobic surface (1)
- Suppression (1)
- Surface chemistry (1)
- Surface functionalization (1)
- Surface interactions (1)
- Surface water (1)
- Surface waters (1)
- Surfacewaters (1)
- Survival rates (1)
- Synchotron (1)
- Synchrotron radiation (1)
- Synchrotron-XPS (1)
- Synergy (1)
- Synthesis (1)
- Synthetic metabolism (1)
- Systematics (1)
- TED-GC/MS (1)
- TEM (1)
- TXRF ambient air aerosol chemical analysis aerosol element composition (1)
- Tanning (1)
- Tannins (1)
- Targeted and nontargeted (1)
- Targeting, Nanoparticles (1)
- Taxonomy (1)
- Temperate rain forest (1)
- Temple Scroll (1)
- Tems (1)
- Terbutryn (1)
- Teredo sp (1)
- Termite control (1)
- Termite-associated microbes (1)
- Termitoidae (1)
- Test method (1)
- Test strip (1)
- Teststreifen (1)
- Text analysis (1)
- Thermal Desorption (1)
- Thermal Extraction (1)
- Thermal analysis (1)
- Thermal degradation (1)
- Thermal imaging (1)
- Thermal properties (1)
- Thermo-desorption (1)
- Thermocouple (1)
- Thermodynamic (1)
- Thermoplastic filaments (1)
- Thioimidazolium (1)
- Tinting (1)
- ToF SIMS (1)
- ToF-SIMS (1)
- Tomography (1)
- Torah (1)
- Torah Scrolls (1)
- Torah scrolls (1)
- Touch surfaces (1)
- Trait-based ecology (1)
- Transmission electron microscopy (1)
- Transport modeling (1)
- Transposon (1)
- Tripartite interactions (1)
- Typology of Inks (1)
- Tyrosine (1)
- UV absorption (1)
- UV protection (1)
- UV tolerance (1)
- UV-VIS Reflectance spectroscopy (1)
- UV-VIS reflectance spectroscopy (1)
- Ultrashort PFAS (1)
- Ultrashort laser processing (1)
- Ultrastructure (1)
- Umweltmessung (1)
- Up-cycling (1)
- Uptake rate (1)
- Uranium (1)
- Uranium mining (1)
- Urban mining (1)
- Ureolytic bacteria (1)
- Utilisation (1)
- Utilization (1)
- VAMAS (1)
- VIS (1)
- VOC Emission (1)
- VOC Emissionen (1)
- VOC emission (1)
- VOC transfer standards (1)
- VOC-Emission (1)
- Validation trial (1)
- Vasari (1)
- Velocimetry (1)
- Vienna manuscript (1)
- Viruses (1)
- Vitriolic iron-gall inks (1)
- Volatile organic compound (1)
- Volatile organic compounds (VOC) (1)
- Vues des Cordillères (1)
- WKI flask method (1)
- Waste incineration (1)
- Waste water (1)
- Waste water treatment (1)
- Water (1)
- Water atmosphere (1)
- Water contact (1)
- Water stable isotope analysis (1)
- Water uptake (1)
- Weathering tests (1)
- Weld fatigue (1)
- Weld toe geometry (1)
- Wet-mechanical treatment (1)
- White-rot fungi (1)
- Wood Modification (1)
- Wood ash (1)
- Wood samples (1)
- Writing Ink (1)
- Writing materials (1)
- X-Ray analysis (1)
- X-Ray fluorescence (1)
- X-ray based techniques (1)
- X-ray diffraction (XRD) (1)
- X-ray fuorescence (1)
- X-ray spectroscopic techniques (1)
- X-ray spectroscopy (1)
- X-ray tomographic (1)
- X-rays (1)
- XRF Analysis (1)
- XRF imaging (1)
- XRF ink analysis (1)
- XRF-, VIS- FTIR-spectroscopy (1)
- Xestobium rufovillosum (1)
- Yeast (1)
- ZIF (1)
- ZIF-8 (1)
- Zearalenone (1)
- Zearalenone sulfate (1)
- Zeolite (1)
- Zeolithe (1)
- Zinc chloride (1)
- Zinc oxide (1)
- a-zearalenol (1)
- biocide tolerance (1)
- black fungi (1)
- black fungus (1)
- carotenoids (1)
- disinfection (1)
- dsDAN monolayer (1)
- evolution (1)
- fertilizer (1)
- fs-laser processing (1)
- fungus (1)
- genomics (1)
- heterogeneity (1)
- historic inks (1)
- iChip (1)
- individual-based modelling (1)
- infrared spectroscopy (1)
- ink (1)
- mRNA-seq (1)
- microspectroscopy (1)
- multi scale testing (1)
- natural ventilation (1)
- openBIS (1)
- pH (1)
- pH probe (1)
- pH sensor (1)
- pHe (1)
- papyrus (1)
- pigmentation (1)
- qPCR (1)
- soil (1)
- underexplored phyla (1)
- x-ray diffraction (1)
- ‘Green’ pesticide (1)
Organisationseinheit der BAM
- 4 Material und Umwelt (812) (entfernen)
Paper des Monats
- ja (19)
In 2018 municipal solid waste (MSW) incineration in Europe produced nearly 19 Mt of bottom ash (BA); only 46 %-wt. was treated, often in poorly performing plants, leaving behind 10 Mt of untreated and unrecovered BA, destined to landfill. This work was based on the inventory of BA across Europe, and on the hypothesis to achieve complete BA valorisation through two assumptions: treating 100% BA and minimizing the loss of valuable fractions due to technical limitations of state-of-the-art processes in comparison to advanced innovative processes. The research involved three phases: characterization of potential secondary raw materials (metals and mineral fraction) currently lost from untreated (the surplus compared to treatment capacity) and unrecovered BA (the fine fraction) through material flow analysis; environmental assessment (energy balance and net GHG emissions) of complete BA valorisation; investigation of the economic feasibility of complete BA Valorisation through state-of-the-art technologies. The resulting 2.14 Mt loss of valuable materials included 1 Mt Mineral fraction and 0.97 Mt ferrous metals, mostly from untreated BA, and 0.18 Mt non-ferrous metals, mostly from unrecovered BA. The energy balance and GHGs emissions required by the treatment of the currently untreated and unrecovered fractions of BA resulted in energy and GHGs emissions savings. Economic profitability was driven by iron and copper recycling and avoided landfill fees. Profitability was achieved by two thirds of considered countries (average values: NPV 83 M€, ROI 20%, payback time 11 years) with BA mass flow exceeding 0.02 Mt.
While studying the history of inks, division 4.5 of the BAM (Bundesanstalt für Materialforschung und Prüfung) together with the Centre for the Study of Manuscript Cultures in Hamburg has developed a protocol for ink analysis. It consists of a primary screening to determine the type of the ink, and a subsequent in-depth analysis using several spectroscopic techniques. One of them, X-ray Fluorescence (XRF) aims primarily at establishing the fingerprints of inks containing metals, making it possible to distinguish among different inks.
Our research aims primarily at recreating a socio-geographic history of inks, parchment, and papyrus and includes the comparative analysis of the writing materials of the Dead Sea Scrolls, ink and papyrus in Ancient and Hellenistic Egypt, and inks in documents from various contemporary medieval communities in Fustat (first nucleus of Cairo) as well as other medieval Jewish and Armenian communities.
The presentation shows the panorama of historic inks and our attempt to follow up the transition of the inks from those based on soot to the iron-gall inks commonly used in the Middle Age.
This chapter offers observations and considerations concerning black writing inks encountered in writing supports transmitting documentary and literary texts of the late Antiquity and early Middle Ages. It discusses different types of inks, the Methods of their detection and their use in different times and geographical areas.
Our study is dedicated to non-destructive characterization of the support and the inks of the DSS.
To that aim we use micro-XRF, 3D- SY-XRF, different IR methods including synchrotron radiation based reflectance spectroscopy, optical and electron microscopy.
The lecture discusses advantages and the shortcomings of the non-destructive testing approach.
In recent years the BAM has been focusing on the characterization of the writing materials of the medieval Torah scrolls. The challenge imposed by the study of this specific type of manuscript led to designing and building dedicated stages to ensure the safety of the scrolls during the analysis. Furthermore, the identification of multiple corrections executed in apparently identical inks required broadening the standard two-step protocol of near infrared reflectography and X-ray fluorescence to include multispectral imaging. This work has prepared the division to participate in the large collaborative project “To roll: Materialisierte Heiligkeit (Materialised Holiness)” based at the Free University, Berlin.
The presentation will demonstrate the aims of the studies, preliminary results and the strategies adopted by the division 4.5 of the BAM.
Microbiologically influenced corrosion (MIC) is a highly unpredictable process dictated by the environment, microorganisms, and the respective electron source. Interaction pathways between cells and the metal surface remain unclear. The development of this novel single cell-inductively coupled plasma-time of flight-mass spectrometry analytical method and a MIC-specific staining procedure facilitate the investigation of steel-MIC interactions. With this it is possible to analyze the multi-elemental fingerprint of individual cells. The detection method revealed elemental selectivity for the corrosive methanogenic archaeal strain Methanobacterium-affiliated IM1. The interface between material and environmental analysis thus receives special attention, e.g., when considering MIC on solid steel. Hence, the possible uptake of individual elements from different steel samples is investigated. Results showed the cells responded at a single-cell level to the different types of supplemented elements and displayed the abilities to interact with chromium, vanadium, titanium, cobalt, and molybdenum from solid metal surfaces. The information obtained will be used in the future to elucidate underlying mechanisms and develop possible material protection concepts, thus combining modern methods of analytical sciences with materials research.
Laser Powder Bed Fusion (L-PBF) is a promising additive manufacturing (AM) technology for metal part production especially for complex and lightweight structures or functional designs. In L PBF processes several by-products including welding plume and its condensates, spatter and ejected powder are generated during laser exposure. Investigations of micro- and nano-sized by-products have received little attention in literature. This study focuses on the analysis of particle emissions in L PBF of 316L stainless steel using a scattered light aerosol spectrometer and a fast mobility particle sizer spectrometer during the process which allows for in-situ analysis of particle sizes in the range of 6 nm to 100 µm. A distinct correlation of emission signals to part position can be revealed. In addition, a significant influence of laser scanning vector directions on emission signals is presented. Furthermore, differing powder layer thicknesses can be recognised by deviations in emission signals.
Laser Powder Bed Fusion (L-PBF) is a promising additive manufacturing (AM) technology for metal part production especially for complex and lightweight structures or functional designs. In L PBF processes several by-products including welding plume and its condensates, spatter and ejected powder are generated during laser exposure. Investigations of micro- and nano-sized by-products have received little attention in literature. This study focuses on the analysis of particle emissions in L PBF of 316L stainless steel using a scattered light aerosol spectrometer and a fast mobility particle sizer spectrometer during the process which allows for in-situ analysis of particle sizes in the range of 6 nm to 100 µm. A distinct correlation of emission signals to part position can be revealed. In addition, a significant influence of laser scanning vector directions on emission signals is presented. Furthermore, differing powder layer thicknesses can be recognised by deviations in emission signals.
The emission of ultrafine particles from small desktop Fused Filament Fabrication (FFF) 3D printers has been frequently investigated in the past years. However, the vast majority of FFF emission and exposure studies have not considered the possible occurrence of particles below the typical detection limit of Condensation Particle Counters and could have systematically underestimated the total particle emission as well as the related exposure risks. Therefore, we comparatively measured particle number concentrations and size distributions of sub-4 nm particles with two commercially available diethylene glycol-based instruments – the TSI 3757 Nano Enhancer and the Airmodus A10 Particle Size Magnifier. Both instruments were evaluated for their suitability of measuring FFF-3D printing emissions in the sub-4 nm size range while operated as a particle counter or as a particle size spectrometer. For particle counting, both instruments match best when the Airmodus system was adjusted to a cut-off of 1.5 nm. For size spectroscopy, both instruments show limitations due to either the fast dynamics or rather low levels of particle emissions from FFF-3D printing in this range. The effects are discussed in detail in this article. The findings could be used to implement sub-4 nm particle measurement in future emission or exposure studies, but also for the development of standard test protocols for FFF-3D printing emissions.
This Special Issue, ‘Measurement of the Environmental Impact of Materials’, is focused on the impact that materials have on the environmental compartments of soil, water and air. Leaching and emission processes, including underlying mechanisms, are a recurring topic in most published articles in the present Special Issue. Contributions have come from three continents and numerous countries (USA, Germany, France, Latvia, Poland, Russia, Japan, Korea and Thailand) indicating the global dimension of the subject.
Throughout their life cycles—from production, usage, through to disposal—materials and products interact with the environment (water, soil, and air). At the same time, they are exposed to environmental influences and, through their emissions, have an impact on the environment, people, and health. Accelerated experimental testing processes can be used to predict the long-term environmental consequences of innovative products before these actually enter the environment.
We are living in a material world. Building materials, geosynthetics, wooden toys, soil, nanomaterials, composites, wastes and more are research subjects examined by the authors of this book. The interactions of materials with the environment are manifold. Therefore, it is important to assess the environmental impact of these interactions. Some answers to how this task can be achieved are given in this Special Issue.
The ISO 16000-6 standard describes a method for the determination of volatile organic compounds (VOCs) in indoor and test chamber air by sorbent-based active sampling, thermal desorption and gas chromatography coupled with mass spectrometry (GC/MS). It also gives directions to adapt this methodology to very volatile organic compounds (VVOCs). Indeed, toxicologically based guideline values are being implemented for these compounds and it becomes necessary to measure them. But a comprehensive and robust measurement method is lacking. This work highlights the points that still need to be explored towards the standardisation of a suitable procedure: investigations on sorbent combinations, the suitability of chromatography columns and the use of gaseous standards are required. The biggest challenge remains in the fact that strong sorbents adsorb water together with VVOCs. Water may impair the analysis and the optimal approach to eliminate it is still to be found and integrated into the sampling strategy.
Excessive discharge of quaternary ammoniumdisinfectants such as benzalkonium chloride (BAC) into aquatic systems can trigger several physiological responses in environmental microorganisms. In this study, we isolated a less-susceptible strain of Aeromonas hydrophila to BAC, designated as INISA09, froma wastewater treatment plant in Costa Rica. We characterized its phenotypic response upon exposure to three dierent concentrations of BAC and characterizedmechanisms related to its resistance using genomic and proteomic approaches. The genome of the strain, mapped against 52 dierent sequenced A. hydrophila strains, consists of approximately 4.6Mb with 4,273 genes. We found a massive genome rearrangement and thousands of missense mutations compared to the reference strain A. hydrophila ATCC 7966.
We identified 15,762 missense mutations mainly associated with transport, antimicrobial resistance, and outer membrane proteins.
In addition, a quantitative proteomic analysis revealed a significant upregulation of several efflux pumps and the downregulation of porins when the strain was exposed to three BAC concentrations.Other genes related tomembrane fatty acid metabolism and redox metabolic reactions also showed an altered expression.
Our findings indicate that the response of A. hydrophila INISA09 to BAC primarily occurs at the envelop level, which is the primary target of BAC. Our study elucidates the mechanisms of antimicrobial susceptibility in aquatic environments against a widely used disinfectant and will help better understand howbacteria can adapt to biocide pollution. To our knowledge, this is the first study addressing the resistance to BAC in an environmental A. hydrophila isolate. We propose that this bacterial species could also serve as a new model to study antimicrobial pollution in aquatic environments.
Mechanisms of olivine dissolution by rock-inhabiting fungi explored using magnesium stable isotopes
(2019)
To unravel the dissolution mechanisms of olivine by a rock-inhabiting fungus we determined the stable isotope ratios of Mg on solutions released in a laboratory experiment. We found that in the presence of the fungus Knufia petricola the olivine dissolution rates were about seven-fold higher (1.04×10−15 mol cm−2 s−1) than those in the abiotic experiments (1.43×10−16 mol cm−2 s−1) conducted under the same experimental condition (pH 6, 25 °C, 94 days). Measured element concentrations and Mg isotope ratios in the supernatant solutions in both the biotic and the abiotic experiment followed a dissolution trend in the initial phase of the experiment, characterized by non-stoichiometric release of Mg and Si and preferential release of 24Mg over 26Mg. In a later phase, the data indicates stoichiometric release of Mg and Si, as well as isotopically congruent Mg release. We Attribute the initial non-stoichiometric phase to the rapid replacement of Mg2+ in the olivine with H+ along with simultaneous polymerization of Si tetrahedra, resulting in high dissolution rates, and the stoichiometric phase to be influenced by the accumulation of a Si-rich amorphous layer that slowed olivine dissolution. We attribute the accelerated dissolution of olivine during the biotic experiment to physical attachment of K. petricola to the Si-richamorphous layer of olivine which potentially results in ist direct exposure to protons released by the fungal cells. These additional protons can diffuse through the Si-rich amorphous layer into the crystalline olivine. Our results also indicate the ability of K. petricola to dissolve Fe precipitates in the Si-rich amorphous layer either by protonation, or by Fe(III) chelation with siderophores. Such dissolution of Fe precipitates increases the porosity of the Si-rich amorphous layer and hence enhances olivine dissolution. The acceleration of mineral dissolution in the presence of a rock-dissolving fungus further suggests that its presence in surficial CO2 sequestration plants may aid to accelerate CO2 binding.
Per- and polyfluoroalkyl substances (PFAS) are a large group of anionic, cationic, or zwitterionic organofluorine surfactants used in the formulations of thousands of products and consumer goods, including aqueous film-forming foams (AFFF) used to suppress aviation fires in training scenarios, non-stick cookware, fast-food wrappers, water-repellent fabrics, medical equipment. Because PFAS have been extensively used in a variety of AFFF products they can be found in soils from industrial and military installations. Current decontamination strategies of PFAS-burdened soils mainly consist of adsorption methods using adsorbents for fixation of PFAS in the ground. A second option is the utilization of a “pump and treat” process, cycling polluted soils through a washing plant leading to the concentration of the pollutants in the fine fraction. Only a subsequent, high-energy consuming pyrolysis process guarantees the total destruction of all fluorinated organic contaminants. Both approaches are cost-intensive and not intended for the direct decomposition of all PFAS contaminants. Hence, there is a great demand for innovative developments and chemical treatment technologies, dealing with new strategies of tackling the PFAS problem. Previously, mechanochemical treatment of polychlorinated organic compounds in soils showed an efficient dechlorination. Thus, we investigated mechanochemical treatment of PFAS contaminated soils with various additives in a ball mill and analyzed the PFAS defluorination with gas chromatography mass spectrometry (GCMS) and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively, as well es the fluoride mineralization by ion chromatography (IC) and fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy.
Current decontamination strategies of PFAS-burdened soils mainly consist of adsorption methods using adsorbents for fixation of PFAS in the ground. A second option is the utilization of a “pump and treat” process, cycling polluted soils through a washing plant leading to the concentration of the pollutants in the fine fraction. Only a subsequent, high-energy consuming pyrolysis process guarantees the total destruction of all fluorinated organic contaminants. These approaches are cost-intensive and not intended for the direct decomposition of all PFAS contaminants. Hence, there is a great demand for innovative developments and chemical treatment technologies, dealing with new strategies of tackling the PFAS problem. Thus, we investigated mechanochemical treatment of PFAS contaminated soils with various additives in a ball mill and analyzed the PFAS defluorination with gas chromatography mass spectrometry (GC-MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively, as well as the fluoride mineralization by ion chromatography (IC) and fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy.
Phosphorus (P) recycling from sewage sludge for agricultural needs has to meet requirements for agricultural implementation, such as short and long-term P-plant-availability under field conditions. Field experiments often bring no evaluable results, because agricultural soils got a high potential of P-supply even if they are classified as low in P-supply according to the CAL extraction method. The present study presents a possible way to investigate the P-plant-availability of P-recycling-fertilizers under field-like conditions. The plant experiments are firstly performed in small Mitscherlich pots in growth chambers and subsequently in containers with a high soil volume of 170 kg under greenhouse conditions, in which plants can grow until ripening. The tested P-recycling fertilizers were produced from sewage sludge in a large-scale thermal process. It was a two-step treatment process performed with a pyrolysis of sewage sludge at 550°C (SSC-550) and a subsequent thermochemical post-treatment at 950°C with Na2SO4 (SSA-Na) and HCl + Na2SO4 (SSA-HCl/Na) as additives. The results show, that the P-recycling-products from pyrolysis got an adequate long-term but a 65% lower short-term P-plant-availability compared to triple superphosphate. SSA-Na and SSA-HCl/Na show both a high short and longterm P-plant-availability comparable to triple-superphosphate. This can be explained by their highly plant-available P-compound CaNaPO4.
Halomonas elongata is a halophilic γ-proteobacterium that synthesizes and accumulates the compatible solute ectoine to cope with osmotic stress in saline environments. Ectoine possesses protecting properties and stabilizes proteins as well as whole cells against stresses like ionizing radiation and cytotoxins. These properties make ectoine a highly demanded ingredient in cosmetics and pharmaceuticals. To date H. elongata is the industrial Producer strain of ectoine, but several metabolic factors for optimum ectoine production remain to be explored.
In this work, we used up to date Metabolic engineering approaches following the ‘Push, Pull, Block – strategy’ to examine targets that contribute to ectoine synthesis. Firstly, the basics of glucose catabolism were inspected to PUSH and enhance carbon flow towards ectoine synthesis. Secondly, lysine biosynthesis was targeted to BLOCK a pathway that is competing for precursors with ectoine synthesis. Thirdly, the mechanosensitive (MS) channels of H. elongata have been examined as possible excretion routes for ectoine. An overexpression of the ectoine excretion channels potentially could PULL out product at the end of ectoine synthesis and increase overall ectoine flux. For the interrogation of central metabolic pathways, we established the new molecular tool CRISPR-mediated interference (CRISPRi) for targeted modulation of gene expression.
PUSH Glucose catabolism through the Entner-Doudoroff (ED) and Emden-Meyerhof-Parnas (EMP) pathway was targeted with CRISPRi and examined on gene expression level for ist response to changing salinity and different carbon sources. Changing salinity did not influence gene expression levels of glucose catabolism but the carbon source glucose triggered glycolysis through the (ED) pathway. When gene expression of the ED pathway was downregulated with CRISPRi, the growth rates remained constant. The observations indicate a metabolic overflow mechanism for glycolysis, in which fluxes are constantly high - even at lower salinity when no resources are demanded for ectoine synthesis. The further analysis of glucose to product conversion rates will advise optimum conditions for future industrial cultivation processes.
BLOCK Lysine biosynthesis was downregulated with CRISPRi, which led to a significant increase in ectoine production. Hence, the blockage of lysine biosynthesis would be a valuable strategy for the optimization of the industrial producer strain in future studies.
PULL MS channels and ectoine regulation are inevitably connected in osmoadaptation. Therefore, ectoine excretion, growth performance and gene expression levels of the MS channels were monitored in steady state conditions and in response to osmotic shock in the wildtype strain and in a MS channel deletion mutant. We observed that the MS channels were essential for the survival of osmotic shock but surprisingly their presence reduced cell growth under high salinity. The MS channels were only partially responsible for ectoine excretion.
Thus, alternative ectoine excretion channels must exist and remain to be explored.
The application of naturally-derived biomolecules in everyday products, replacing conventional synthetic manufacturing, is an ever-increasing market. An example of this is the compatible solute ectoine, which is contained in a plethora of treatment formulations for medicinal products and cosmetics. As of today, ectoine is produced in a scale of tons each year by the natural producer Halomonas elongata. In this work, we explore two complementary approaches to obtain genetically improved producer strains for ectoine production. We explore the effect of increased precursor supply (oxaloacetate) on ectoine production, as well as an implementation of increased ectoine demand through the overexpression of a transporter. Both approaches were implemented on an already genetically modified ectoine-excreting strain H. elongata KB2.13 (ΔteaABC ΔdoeA) and both led to new strains with higher ectoine excretion. The supply driven approach led to a 45% increase in ectoine titers in two different strains. This increase was attributed to the removal of phosphoenolpyruvate carboxykinase (PEPCK), which allowed the conversion of 17.9% of the glucose substrate to ectoine. For the demand driven approach, we investigated the potential of the TeaBC transmembrane proteins from the ectoine-specific Tripartite ATP-Independent Periplasmic (TRAP) transporter as export channels to improve ectoine excretion. In the absence of the substrate-binding protein TeaA, an overexpression of both subunits TeaBC facilitated a three-fold increased excretion rate of ectoine. Individually, the large subunit TeaC showed an approximately five times higher extracellular ectoine concentration per dry weight compared to TeaBC shortly after its expression was induced. However, the detrimental effect on growth and ectoine titer at the end of the process hints toward a negative impact of TeaC overexpression on membrane integrity and possibly leads to cell lysis. By using either strategy, the ectoine synthesis and excretion in H. elongata could be boosted drastically. The inherent complementary nature of these approaches point at a coordinated implementation of both as a promising strategy for future projects in Metabolic Engineering. Moreover, a wide variation of intracelllular ectoine levels was observed between the strains, which points at a major disruption of mechanisms responsible for ectoine regulation in strain KB2.13.
Coastal oceans receive large amounts of anthropogenic fixed nitrogen (N), most of which is denitrified in the sediment before reaching the open ocean. Sandy sediments, which are common in coastal regions, seem to play an important role in catalysing this N‐loss. Permeable sediments are characterized by advective porewater transport, which supplies high fluxes of organic matter into the sediment, but also leads to fluctuations in oxygen and nitrate concentrations. Little is known about how the denitrifying communities in these sediments are adapted to such fluctuations. Our combined results indicate that denitrification in eutrophied sandy sediments from the world's largest tidal flat system, the Wadden Sea, is carried out by different groups of microorganisms. This segregation leads to the formation of N2O which is advectively transported to the overlying waters and thereby emitted to the atmosphere. At the same time, the production of N2O within the sediment supports a subset of Flavobacteriia which appear to be specialized on N2O reduction. If the mechanisms shown here are active in other coastal zones, then denitrification in eutrophied sandy sediments may substantially contribute to current marine N2O emissions.
Metagenomic datasets of air samples collected during episodes of severe smoke-haze in Malaysia
(2021)
Transboundary emissions of smoke-haze from land and forest fires have recurred annually during the dry period (June to October, over the past few decades) in South East Asia. Hazardous air quality has been recorded in Malaysia during these episodes. Agricultural practices such as slash-and-burn of biomass and peat fires particularly in Sumatera and Kalimantan, Indonesia, have been implicated as the major causes of the haze. Past findings have shown that a diversity of microbes can thrive in air including in smoke-haze polluted air. In this study, metagenomic data were generated to reveal the diversity of microorganisms in air during days with and without haze. Air samples were collected during non-haze (2013A01) and two haze (2013A04 and 2013A05) periods in the month of June 2013. DNA was extracted from the samples, subjected to Multiple Displacement Amplification and whole genome sequencing (Next Generation Sequencing) using the HiSeq 2000 Platform. Extensive bio-informatic analyses of the raw sequence data then followed. Raw reads from these six air samples were deposited in the NCBI SRA databases under Bioproject PRJNA662021 with accession numbers SRX9087478, SRX9087479 and SRX9087480.
Municipal solid waste incineration (MSWI) is one of the leading technologies for municipal solid waste (MSW) treatment in Europe. Incineration bottom ash (IBA) is the main solid residue from MSWI, and its annual European production is about 20 million tons. The composition of IBA depends on the composition of the incinerated waste; therefore, it may contain significant amounts of ferrous and non-ferrous (NFe) metals as well as glass that can be recovered. Technologies for NFe metals recovery have emerged in IBA treatment since the 1990s and became common practice in many developed countries. Although the principles and used apparatus are nearly the same in all treatment trains, the differences in technological approaches to recovery of valuable components from IBA – with a special focus on NFe metals recovery – are summarized in this paper.
A non-invasive methodological approach has been carried out to identify the pigments and classify the binding media of the reverse painting on glass Kreuzabnahme (1914/15) by Carlo Mense.
Mense was a member of the group Rhenish Expressionists around August Macke and got interested in the technique of painting on the reverse side of a glass panel. The studied painting indicates a remarkably painted reverse and front side, which creates a unique visual appearance of the glass. The applied noninvasive, spectroscopic approach includes X-ray fluorescence, VIS spectroscopy, Raman spectroscopy and diffuse reflectance infrared Fourier transform spectroscopy. The measurements revealed inorganic Pigments mixed with drying oil as binder. Together with common pigments, such as lead white, barium sulphate, bone black, cinnabar, chrome yellow, ochre, and viridian, an unusual additional material was found, Strontium white.
EN 16516 sets specifications for the determination of emissions into indoor air from construction products. Reliable, accurate and International System of Unit (SI)-traceable measurement results of the emissions are the key to consumer protection. Such measurement results can be obtained by using metrologically traceable reference materials. Gas-phase standards of volatile organic compounds (VOCs) in air can be prepared by a variety of dynamic methods according to the ISO 6145 series. However, these methods are not always applicable for semi-VOCs (SVOCs) due to their high boiling point and low vapour pressure. Therefore, a novel dynamic gas mixture generation system has been developed. With this system gas-phase standards with trace level VOCs and SVOCs in air can be prepared between 10 nmol mol−1 and 1000 nmol mol−1. The VOCs and SVOCs in this study have normal boiling points ranging from 146 °C to 343 °C. Metrologically traceable reference materials of the gas-phase standard were obtained by sampling of the VOC gas-phase standard into Tenax TA® sorbent material in SilcoNert® coated stainless steel tubes. Accurately known masses between 10 ng and 1000 ng per VOC were sampled. These reference materials were used to validate the dynamic system. Furthermore, the storage and stability periods of the VOCs in the reference materials were determined as these are crucial characteristics to obtain accurate and SI-traceable reference materials. In a round robin test (RRT), the reference materials were used with the aim of demonstrating the feasibility of providing SI-traceable standard reference values for SVOCs for interlaboratory comparison purposes. Based on the results from the validation, the storage and stability studies and the RRT, gas-phase standards and reference materials of VOCs and SVOCs with relative expanded uncertainties between 5% and 12% (k = 2) have been developed. These reference standards can be used as calibrants, reference materials or quality control materials for the analysis of VOC emissions.
In industrialised countries more than 80% of the time is spent indoors. Products, such as building materials and furniture, emit volatile organic compounds (VOCs), which are therefore ubiquitous in indoor air. Different VOC combinations may, under certain environmental and occupational conditions, result in reported sensory irritation and health complaints. A healthy indoor environment can be achieved by controlling the sources and by eliminating or limiting the release of harmful substances into the air. One way is to use materials proven to be low emitting. Meanwhile, a worldwide network of professional commercial and non-commercial laboratories performing emission tests for the evaluation of products for interior use has been established. Therefore, comparability and metrological traceability of test results must be ensured. A laboratory’s proficiency can be proven by internal and external validation measures that both include the application of suitable reference materials. The emission test chamber procedure according to EN 16516 comprises several steps from sample preparation to sampling of test chamber air and chromatographic analysis. Quality assurance and quality control (QA/QC) must therefore be ensured. Currently, there is a lack of suitable reference products containing components relevant for the health-related evaluation of building products.
The EU-funded EMPIR project 20NRM04 MetrIAQ (Metrology for the determination of emissions of dangerous substances from building materials into indoor air) aims to develop 1) gaseous primary reference materials (gPRM), which are used for the certification of gaseous (certified) reference materials (gCRM) and 2) emission reference materials (ERM).
Most commercial gas standards of indoor-relevant compounds are not certified due to the lack of primary reference materials to which the project aims to contribute. The gPRM under development is a gas-phase standard containing trace levels of VOCs in nitrogen or air from the check standard according to EN 16516 (n-hexane, methyl isobutyl ketone, toluene, butyl acetate, cyclohexanone, o-xylene, phenol, 1,3,5-trimethylbenzene) with a target uncertainty of 5 %. The gPRM can be sampled into sorbent tubes to obtain transfer standards in the form of gCRM.
The well characterised ERM represents a sample of a test specimen, e.g. building material, that is loaded into the emission test chamber for a period of several days and is used to evaluate the whole emission test chamber procedure. It shall have a reproducible and temporally constant compound release of less than 10 % variability over 14 days. Different approaches for retarded VOC release, such as the encapsulation of pure compounds and the impregnation of porous materials, are being tested to reach this aim. Furthermore, the design of the ERM is accompanied by the development of a numerical model for the prediction of the emissions for each of the target VOCs. The current progress of the work on both materials will be presented.
Microbiologically influenced corrosion (MIC) of iron is usually attributed to sulfate-reducing microorganisms, either chemically (formation of hydrogen sulfide) or electrically (direct electron uptake). Methanogenetic Archaea are also known to be involved in iron corrosion, forming a multi-species biofilm on corroding metallic structures. However, mechanistic details and kinetics of the overall process in methanogen-induced MIC are poorly understood.
Microbially influenced corrosion (MIC) of iron is usually attributed to sulfate-reducing microorganisms (SRM) which act upon the metal by the reactiveness of hydrogen sulfide, and by withdrawal of the available electrons (Fe → Fe²⁺ + 2e⁻ ; E° = 0.47 V) in electrical contact through surface attachment. Also methanogenic archaea are supposed to cause MIC. Because they do not produce hydrogen sulfide, withdrawal of electrons may be their main corrosive mechanism; however, mechanistic details and kinetics of the overall process are poorly understood. Precipitation of siderite (4Fe + 5HCO₃⁻ + 5H⁺ → 4FeCO₃ + CH₄ + 3H₂O) can lead to an insulating layer on the metal surface and lower the corrosion rate. Still, the extent of FeCO₃ precipitation may be significantly influenced by environmental conditions such as pH and advective processes.
To investigate the corrosive potential of methanogens, we studied strains isolated from marine sediments (Methanococcus maripaludis 14266, 2067, Methanobacterium-affiliated strain IM1), crude oil tanks (Methanococcus maripaludis Mic1c10, KA1) and the oral cavity (Methanobrevibacter oralis) in a closed (batch) culture, and in a sand-packed flow-through cell with pH control and simulation of a fluctuating environment. Results indicate that the rates of iron corrosion due to coupled methanogenesis (up to 0.3 mm/yr) are comparable to that caused by SRM. Surface analyses of the metal showed severe pitting. Such knowledge and deeper understanding also from an electrokinetic point of view may not only provide further models in microbial electrophysiology, but also contribute to mitigation strategies in MIC.
Microbially influenced corrosion (MIC) of iron is usually attributed to sulfate-reducing microorganisms (SRM) which act upon the metal by the reactiveness of hydrogen sulfide, and by withdrawal of the available electrons in electrical contact with the metal. Methanogenic archaea are supposed to cause MIC. Because they do not produce hydrogen sulfide, withdrawal of electrons may be their main corrosive mechanism; however, mechanistic details and kinetics of the overall process are poorly understood. Precipitation of siderite (4Fe + 5HCO3 + 5H+ 4FeCO3 + CH4 + 3H2O) can lead to an insulating layer on the metal surface and lower the corrosion rate. Still, the extent of FeCO3 precipitation may be significantly influenced by environmental conditions such as pH and advective processes.
Microbially influenced corrosion (MIC) of iron is usually attributed to sulfate-reducing microorganisms (SRM) which act upon the metal by the reactiveness of hydrogen sulfide, and by withdrawal of the available electrons in electrical contact with the metal. Methanogenic archaea are supposed to cause MIC. Because they do not produce hydrogen sulfide, withdrawal of electrons may be their main corrosive mechanism; however, mechanistic details and kinetics of the overall process are poorly understood. Precipitation of siderite (4Fe + 5HCO3 + 5H+ 4FeCO3 + CH4 + 3H2O) can lead to an insulating layer on the metal surface and lower the corrosion rate. Still, the extent of FeCO3 precipitation may be significantly influenced by environmental conditions such as pH and advective processes.
The existence of microbial activity hotspots in temperate regions of Earth is driven by soil heterogeneities, especially the temporal and spatial availability of nutrients. Here we investigate whether microbial activity hotspots also exist in lithic microhabitats in one of the most arid regions of the world, the Atacama Desert in Chile. While previous studies evaluated the total DNA fraction to elucidate the microbial communities, we here for the first time use a DNA separation approach on lithic microhabitats, together with metagenomics and other analysis methods (i.e., ATP, PLFA, and metabolite analysis) to specifically gain insights on the living and potentially active microbial community. Our results show that hypolith colonized rocks are microbial hotspots in the desert environment. In contrast, our data do not support such a conclusion for gypsum crust and salt rock environments, because only limited microbial activity could be observed. The hypolith community is dominated by phototrophs, mostly Cyanobacteria and Chloroflexi, at both study sites. The gypsum crusts are dominated by methylotrophs and heterotrophic phototrophs, mostly Chloroflexi, and the salt rocks (halite nodules) by phototrophic and halotolerant endoliths, mostly Cyanobacteria and Archaea. The major environmental constraints in the organic-poor arid and hyperarid Atacama Desert are water availability and UV irradiation, allowing phototrophs and other extremophiles to play a key role in desert ecology.
Microbial modelling of sulfate-reducing bacteria (SRB) and methanogenic archaea (ME) using iron
(2019)
Sulfate reducing bacteria (SRB) and methanogenic archaea (MA) are commonly found in the oil and gas environments. The formation of hydrogen sulfide (HS-) is particularly concerning for the petroleum industry due to its corrosiveness. However, the activities of SRB are limited to the concentration of sulfate present in the environment, whereas methanogens can utilize substrates such as H¬2 for methanogenesis. MA is commonly found in sulfate-free environments, such as deep sediments, and are known to form interspecies electron transfer relationships with SRB. Recently, SRB and MA capable of microbiologically influenced corrosion (MIC) by using elemental iron as a direct electron source (EMIC) have gained increased attention. On the iron surface, EMIC-SRB can outcompete EMIC-MA in the presence of sulfate, but this changes as sulfate depletes. The formation of FeS on the metal surface can be further utilized by MA for methanogenesis as it provides a conductive path. However, the possible kinetics involved of the overall process are currently unknown.
We obtained a co-culture of EMIC-SRB and EMIC-MA to investigate the growth rates and electrical potential changes under different environmental conditions, including changes in pH, temperature and salinity. Results indicate that under neutral conditions and using iron as the sole substrate, methane production (up to 5 mM) starts after sulfate was depleted. Electrochemical measurements will be conducted on the co-culture under different conditions to determine the changes in the electrical potential in correlation with the sulfate and methane concentration. Fluorescence and electron microscope images of the biofilm structure will be used to visualize cell distribution and morphology. This study embarks the first step of understanding the relationship between EMIC-SRB and EMIC-MA. Such knowledge is important for the field of microbial electrophysiology and can be further explored for industrial applications.
The survey of Canadian shale sites showed a dominance of halophilic microorganisms, including Halomonas (HA). Nitrate-amended incubations of the field samples under high salinity (14.6% NaCl), revealed a dominance of HA (>72%) and an accumulation of nitrite. Nitrite accumulation directly inhibited the growth of SRB, thereby decreasing their souring and corrosion risks. However, accumulated nitrite may also contribute to iron corrosion, which will be tested by using different concentrations of nitrate as an electron acceptor to HA. Different salinities are further tested on HA strains supplemented with iron coupons to determine their effects on iron corrosion rates. HA incubated with separate cultures of corrosive methanogen and SRB were tested to determine whether a positive or adverse effect will occur between them. Lastly, analyses of iron coupons will be conducted using TOF-SIMS, FIB-SEM and EDS for corrosion product characterization
Microbiologically influenced corrosion (MIC) is a phenomenon of increasing concern which affects various materials and sectors of society. MIC describes the effects, often negative, that a material can experience due to the presence of microorganisms. Unfortunately, although several research groups and industrial actors worldwide have already addressed MIC, discussions are fragmented, while information sharing and willingness to reach out to other disciplines is limited. A truly interdisciplinary approach, that would be logical for this material/biology/chemistry-related challenge, is rarely taken. In this review we highlight critical non-biological aspects of MIC that can sometimes be overlooked by microbiologists working on MIC but are highly relevant for an overall understanding of this phenomenon. Here, we identify gaps, methods and approaches to help solve MIC related challenges, with an emphasis on the MIC of metals. We also discuss the application of existing tools and approaches for managing MIC and propose ideas to promote an improved understanding of MIC. Furthermore, we highlight areas where the insights and expertise of microbiologists are needed to help progress this field.
Microbiologically Influenced Corrosion of Cast Iron Containers for High-Level Nuclear Waste Disposal
(2022)
Ductile and corrosion resistant cast iron is investigated as a potential container material to store high-level nuclear waste (HLW) in deep geological repositories (DGR) in claystone bedrock. The dynamic corrosion process is dependent on the conditions present in the DGR which are influenced and/or controlled by geochemical parameters (e.g., redox potential, pH, presence of and ionic concentration in (pore-)water), physical parameters (e.g., pressure), and the influence of metabolically active microorganisms. Cast iron corrosion will occur at the intersection of container and its decontaminable coating with the bentonite backfill material which contains natural microbial populations.
The conditions in a DGR are simulated in microcosm experiments to investigate the impact of microbiologically influenced corrosion (MIC); the microcosms contain: B27 bentonite, synthetic pore water, N2 or N2-CO2 atmosphere, cast iron coupons, as well as the bacterium Desulfosporosinus burensis (isolated from repository depth in Buré, France). Three coupon configurations will be used: untreated, coated with decontaminable coating, and coated with decontaminable coating which has been damaged to simulate possible damages. The microcosms will be examined for bio- and geochemical parameters, such as pH, redox potential, mineral phases, sulphate concentration, Fe(II):Fe(III), changes in microbial populations, and the corrosion process for formation of corrosion products, and potential microbial influence, after a 270-day incubation period at 25°C under anaerobic conditions. In subsequent experiments, the sorption behavior of lanthanides and actinides onto the membranes of viable cells and spores of D. burensis, as well as the surface of corroded cast iron coupons will be investigated.
In the modern world there is an increased understanding that design and performance monitoring of materials have to be tested in connection to chemical, physical and (micro)biological challenges. A systematic study on how biofilms interact with materials and what could be done to engineer biofilms and/or materials in order to maximize the resistance of the material (surface) or the resistance the biofilm-modified material (bulk) is in strong need. In the Department “Materials and the Environment” of the BAM new experimental platform is being developed. With the help of different type of device for high throughput and microbiologically-controlled environment simulation we establish a new approach to clarify the mechanisms of biofilm/material interactions. Despite the focus on fundamental research, the main results of this project proposal will be transferable into material technology and construction chemistry and will influence the development of standardization in this topic. As the interactions of biofilms and materials have implications for most constructions as well as climate change, the results of the research generates additional value.
Climate change is becoming one of the greatest challenges facing our society, particularly due to the continued use of fossil fuels. The steadily increasing demand for energy and the continuously growing world population will further intensify these challenges. The development of renewable energies is therefore of central importance. The 2020 EU Energy Roadmap aims to increase the share of renewable energies (gross energy consumption) to 55% by 2050.
Hydrogen (H2) has the highest potential to become the primary renewable energy source. It is envisioned that by 2050 up to 24% of the total energy demand of Europe is to be ensured by H2. However, a decisive disadvantage of the climate friendly alternatives is the massive containment demand, which needs to be highly secure, cost efficient and easily extractable.
Underground geological formations (UGF) represent a seemingly optimal alternative to meet the rapidly increasing storage demand. In this context, many studies are currently underway to determine the feasibility and risks of UGF. However, little or no consideration is being given to microbiology. Therefore, in this Research Topic we will focus on achieving a greater understanding of the impact microorganisms exert on UGF, with a particular emphasis on interdisciplinary studies.
As many subsurface microbial communities can use H2 as an electron donor, production of seemingly undesirable metabolic byproducts, such as hydrogen sulfide, methane, and acids, are also to be expected. However, the rate of the H2 conversion by the microorganisms, how their metabolic activities impact the UGF on a short-term and long-term scale, the extent of damages microorganisms exert on the infrastructure, or potential use of microorganisms to enhance UGF are just a few questions that require urgent research to assess the role of microorganisms in this new anthropogenic use of the subsurface environment. These and many questions can be addressed in this article collection. In particular, understanding microbial community changes and activity rates will help assess operational and environmental risks, develop mitigation strategies and provide new insights on life under extreme conditions (i.e., pressure, salinity).
In this Research Topic, the editorial team particularly welcomes Original Research, Hypothesis and Theory, Method, and Review manuscripts that deal with the latest advances in microbiology in formations that are planned or currently prepared for hydrogen storage, from both fundamental and practical points of view. The ultimate objective is to promote a deeper understanding into the sustainability of UGF and generate interdisciplinary research involving microbiologists, reservoir engineers, geologists, chemists, physicists.
The topics of interest include, but are not limited to:
• Microbial diversity in different underground hydrogen storage sites or formations currently being considered for hydrogen storage
• Mechanism and impact of microbial growth under high H2 pressure
• Potential role of microorganisms in the short-term and long-term storage of hydrogen
• Potential influences of microorganisms on the hydrogen storage infrastructure systems, e.g., microbiologically influenced corrosion, biofilm growth
• Hydrogen-solid-microorganism interactions, including the influence of microbial growth on UGF geological parameters
• Mechanism and modelling of microbial impact on hydrogen storage
UGF relevant for this Research Topic include porous media, salt caverns, deep aquifers, hard rock caverns and depleted oil/gas reservoirs.
Fungal pigments such as melanin and carotenoids are distinctive markers of animal and plant pathogenic fungi as well as their environmental relatives. These complex pigments play important roles in pathogenicity and stress tolerance while also being useful as biomarkers. Accordingly, it is important to be able to identify in situ the pigments in black fungi, a group of clinical and environmental importance. In this study, wild-type and genetically modified strains of Knufia petricola A95 and wild fungal cells attached to ancient rock were investigated for their spectroscopic and microscopic Raman features and morphological appearance. Knockout mutants of melanin synthesis genes pks1 (polyketide synthase), sdh1 (scytalone dehydratase), and both pks1 and the carotenoid synthesis gene phd1 (phytoene desaturase) were studied We applied two different Raman microscopes using two lasers, with 633 nm and 488 nm wavelengths. We analyzed and compared Raman spectra between the measured reference substances and the mutant and wild-type strains. In the wild strain WT:A95, the peaks close to melanin peals were found at 1353 cm−1 and 1611 cm−1. There are no characteristic melanin peaks at 1580–1600 cm−1 and around 1350 cm−1 at the spectrum of the Δpks1/Δphd1 mutant and the Δsdh1 mutant. The Δpks1 mutant spectrum has the peaks at the beta-carotene v2 C-C in-plane stretch at 1155 cm−1 and v3 C-CH3 deformation at 1005 cm−1. The peaks of carotenoids and melanin were found in all mutants and the wild strain, except the Δpks1/Δphd1 mutant. Raman spectra allow for discrimination between the various pigments. Hence, interactions between natural fungal melanin, as well as other protective pigments, and complex environmental matrices can be characterized on a range of spatial and temporal scales.
Microspectroscopy reveals dust-derived apatite grains in acidic, highly-weathered Hawaiian soils
(2021)
Dust deposition is an important source of phosphorus (P) to many ecosystems. However, there is little evidence of dust-derived P-containing minerals in soils. Here we studied P forms along a well-described climatic Gradient on Hawaii, which is also a dust deposition gradient. Soil mineralogy and soil P forms from six sites along the climatic gradient were analyzed with bulk (X-ray diffraction and P K-edge X-ray absorption near edge structure) and microscale (X-ray fluorescence, P K-edge X-ray absorption near edge structure, and Raman) analysis methods. In the wettest soils, apatite grains ranging from 5 to 30 μm in size were co-located at the micro-scale with quartz, a known continental dust indicator suggesting recent atmospheric deposition. In addition to co-location with quartz, further evidence of dust-derived P included backward trajectory modeling indicating that dust particles could be brought to Hawaii from the major global dust-loading areas in central Asia and northern Africa. Although it is not certain whether the individual observed apatite grains were derived from long-distance transport of dust, or from local dust sources such as volcanic ash or windblown fertilizer, these observations offer direct evidence that P-containing minerals have reached surface layers of highly-weathered grassland soils through atmospheric deposition.
Dust deposition is an important source of phosphorus (P) to many ecosystems. However, there is little evidence of dust-derived P-containing minerals in soils. Here we studied P forms along a well-described climatic gradient on Hawaii, which is also a dust deposition gradient. Soil mineralogy and soil P forms from six sites along the climatic gradient were analyzed with bulk (X-ray diffraction and P K-edge X-ray absorption near edge structure)
and microscale (X-ray fluorescence, P K-edge X-ray absorption near edge structure, and Raman) analysis methods. In the wettest soils, apatite grains ranging from 5 to 30 μm in size were co-located at the micro-scale with quartz, a known continental dust indicator suggesting recent atmospheric deposition. In addition to colocation with quartz, further evidence of dust-derived P included backward trajectory modeling indicating that dust particles could be brought to Hawaii from the major global dust-loading areas in central Asia and northern Africa. Although it is not certain whether the individual observed apatite grains were derived from long-distance transport of dust, or from local dust sources such as volcanic ash or windblown fertilizer, these observations offer direct evidence that P-containing minerals have reached surface layers of highly-weathered grassland soils
through atmospheric deposition.
The concept of circular economy supports mitigation of climate change and other environmental pressures to the planet. Circulating materials in anthropogenic processes come with the risk of accumulating hazardous substances and compounds. In this concept, waste incineration or waste-to-energy (WtE) is a necessary technology to remove these compounds from the life cycle. In this mini-review, contaminants of major importance in the flue gas from waste incineration plants and their environmental impact are discussed. Air pollution of WtE is often seen as the most relevant environmental impact of this treatment option. The emission values parameter set for different countries is presented and compared. The most stringent legally set of emission values could be found in parts of Europe and South Korea. Japan also permits similar strict values when authorising individual incineration plants. In North America, the values are partially less strict as the best available technologies in Europe suggest being possible. Emerging economies, such as India and China, have shown efforts to improve their environmental protection standards but still have room to improve. This could be set in relation to other industrial emitting processes and therefore could be used to assess the relevance of this industry sector to the national emission inventories.
Fused filament fabrication (FFF) on desktop 3D printers is a material extrusion-based technique often used by educational institutions, small enterprises and private households. Polymeric filaments are melted and extruded through a heated nozzle to form a 3D object in layers. The extrusion temperature is therefore a key parameter for a successful print job, but also one of the main driving factors for the emission of harmful air pollutants, namely ultrafine particles and volatile organic gases, which are formed by thermal stress on the polymeric feedstock. The awareness of potential health risks has increased the number of emission studies in the past years. However, the multiplicity of study designs makes an objective comparison of emission data challenging because printer hardware factors such as the actual extruder temperature (TE) and also feedstockspecific emissions are not considered. We assume that across the market of commercial low- and mid-price FFF printers substantial deviations between actual and set extruder temperatures exist, which have a strong effect on the emissions and hence may bias the findings of exposure studies. In our last publication, we presented a standardized feedstock-specific emission test method and showed that for each investigated feedstock an increase in actual extruder temperature was accompanied by an increase in particle emissions (Tang and Seeger, 2022). Therefore, any systematic discrepancy between set and actual extruder temperature matters. In this study, we used a thermocouple and an infrared camera to measure the actual extruder temperatures at different heights. We found significant under- and overestimation of the actual extruder temperatures by the respective set temperatures in three commercial printers. This caused a broad variation of the measured total numbers of emitted particles (TP), even when the same feedstock was operated. For the determination of TP, we followed the DE-UZ 219 test guideline. In a second round we repeated the tests with all printers adjusted to exactly the same extruder temperatures, i.e., to TE=230°C for ABS and TE=210°C for PLA. All measurements were conducted in a 1 m³ emission test chamber. Particle emissions in the size range between 4 nm and 20 μm were detected. Printing on three different printer models without temperature adjustment resulted for each of the investigated feedstocks in a variation in TP of around two orders of magnitude. After temperature adjustment, this was substantially reduced to approx. one order of magnitude and hence minimizes the bias of printer hardware on the emissions. Our findings suggest that adjustment of the extruder temperature should be mandatory in emission testing standards. It also poses a more accurate benchmark and provides more reliable emission data for evaluation of indoor air quality or for health risk assessments. In addition, a proper temperature setting is in the interest of the user. Some commercial FFF printers may have a higher actual extruder temperature than displayed and unintended overheating may not only impair the print quality but may cause unnecessarily increased exposure to particle emissions.
Herein we report the synthesis of a zeolitic imidazolate framework (ZIF-8) by an easy “mix and wait” procedure. In a closed vial, without any interference, the mixture of 2-methylimidazole and basic zinc carbonate assembles into the crystalline product with approx. 90% conversion after 70 h. The reaction exhibits sigmoidal kinetics due to the self-generated water which accelerates the reaction.
In this article, we present two Coptic papyri, P 11934 and P 11935 from the Berlin collection excavated in Ashmunein (ancient Hermopolis) by Otto Rubensohn in 1906. We employ a multi-disciplinary approach that takes into account both their materiality – writing support as well as ink – and their content, as has become ‘best practice’. 1 Material aspects of written documents have traditionally been the purview of papyrologists. Recently developed methods of scientific analysis generate sets of archaeometric data with the potential to improve understanding of the materiality of ancient document production, as well as to yield new evidence for genuine papyrological research questions. To achieve this, a large corpus of comparative data needs to be built. Our contribution offers a first step in this direction. We aim at presenting the papyri, which were selected because of the ink corrosion during conservation work at the Berlin collection, in a format that is exhaustive both for material and textual aspects. The inks from both papyri were analysed using a combination of techniques, contributing to our better understanding of the development of ink technology in Late Antiquity.
Initial situation:
Aluminum is an often-used building material in modern architecture, not only for construction but as well for facades and decorative elements. In the 1950th and 1960th, after World War II, many buildings in Germany were constructed with aluminum or contain elements of colored anodized aluminum. In the last years a larger number of these buildings are increasingly in the sight of conservation works including the aluminum parts such as window frames or facade coverings.
Damaged Aluminum Surfaces:
Common damages are a change of color or gloss changes through weathering processes, drill holes or marks due to later modifications, scratches in the anodized layer due to extensive wear e.g. at handrails or door handles.
To repair damaged aluminum surfaces, there are usually two options: smaller damaged areas are repaired by using a touch-up pen. In case of larger damages, the complete re-anodization is necessary. This includes to de-anodize the surface with cleaning and grinding the whole aluminum object. Both possibilities are disadvantageous for the objects. The touch-up pen often does not match the color of the original surface together with an insufficient corrosion protection for outdoors. While the newly anodized surface differs in color and gloss from the originally applied color.
Research Approach:
The whole procedure contrasts with the principal approach in conservation which aims to intervene as less as possible, in case of the conservation of an object. To fulfill this approach in a more appropriate way the research project focuses on a mobile and partial application for colored, anodized aluminum parts.
To anodize aluminum the application of an electrolyte onto the surface together with sufficient voltage and current is necessary. Generally diluted sulfuric acid is used as electrolyte. Different possibilities are examined to enable the mobile application of the electrolyte, e. g. the application by producing a gel matrix or like in electroplating by pen or brush wrapped with a fleece fabric.
Experimental part:
First experiments are conducted to examine the structure of the anodized layer in relation with proper cleaning, anodization time with applied voltage and current and the coloring process. The aim was to reduce the preparation procedure and the anodization time as much as possible to facilitate the mobile application.
Examinations with Keyence microscope, Eddy current testing and REM are performed to characterize the layers. The results are shown in table 1. A clear connection between proper cleaning, anodization time, voltage and amperage and the achieved thickness of the anodized layer is significant. Cracks in the layer show that raising the voltage and amperage results in thicker layers but as well in a crumbled and less stable anodized surface.
Gel preparation:
In addition to the anodization process with a liquid e.g. sulfuric acid a gel application is tested to prevent the electrolyte from rinsing down during the mobile application. For this purpose, several gel-forming agents are tested together with their stability in acid systems. It was observed, that the consistency of the gels varies dependent of the time.
Conductivity:
The conductivity of sulfuric acid combined with different gel-systems was measured and compared in order to predict the possible growth of layers during anodic oxidation process.
Further steps:
Determination and optimization of application parameters like voltage, amperage and anodization-time to build up a preferably stable and sufficient thick anodized layer. Examination of gel preparation to guarantee a stable product, enforcing with textile tape for easy application.
Bacterial samples are typically freeze dried or cryo-prepared prior to XPS analysis to allow for measurements in ultra-high vacuum (UHV). The sample environment in the near-ambient pressure (NAP) XPS instrument EnviroESCA allows for measurements in up to 15 mbar water vapor, thus, sample preparation is no longer restricted to UHV-compatible techniques. For instance, biofilms grown in medium can be transferred directly from the medium to the measurements chamber, maintaining a humid environment throughout the measurements. Considering the complexity of bacterial samples, sample preparation must be carefully considered in order to obtain meaningful and reproducible results.
In this talk, various strategies for sample preparation of bacteria and biofilms for NAP-XPS measurements will be discussed. Model systems of planktonic bacteria, artificial biofilms resembling the exopolysaccharide matrix and biofilms have been characterised in various conditions. The stability and homogeneity of the samples was assessed by monitoring the C1s core level peak at different sample locations. The quality of the XPS-spectra is also influenced by the gas environment, which will be exemplified by core level spectra of P. Fluorescens acquired in air, water vapor and ultra-high vacuum.
Morphologically simple and microbially dominated ecosystems termed “biofilms” have existed on Earth for a long period of biosphere evolution. A model biofilm combining one heterotroph and one phototroph component was used in a laboratory experiment to simulate biogenic weathering with two different specimens of basic rock samples from the soil profiles. The rocks fragments from the regions of cold environments of Eurasia,where abiotic physical processes, including rock disintegration initiated by freezing–thawing cycles, represent the most probable Scenario of rock weathering, were subjected to biological colonization. The rock Fragments were represented by dolerite and metagabbro amphibolites. Polished sections of the rock samples were inoculated with the model microbiological consortium of the oligotrophic fungus and the phototrophic cyanobacteria (biofilm). After 3 month runtime of the experiment the progress of rock weathering was derived from the growth of the biofilm on the rock surfaces. The model biofilm visualization on the rock surface of polished sections illustrated their stronger development namely on dolerite in comparison with metagabbro amphibolite. The findings confirmed the higher sensitivity of dolerite to biogenic weathering due to (i) mineral association, in which quartz was absent and (ii) porosity providing higher specific surface area for biotic—abiotic interaction influenced by the occurrence of micro-porosity in the rock.
Rock-inhabiting black fungi are adapted to survive extreme stresses such as radiation and lack of water and are thus able to colonise arid material surfaces like solar panels and marble monuments. Black fungi can typically grow as one of two cell types: depending on the environmental conditions, they are able to form yeast-like cells or hyphal filaments. Knufia petricola is one member of the rock-inhabiting black fungi which functions as a model reference species. As there is no mathematical model for biofilm formation of RIF, we are going to develop a model for K. petricola which describes fungal growth on the level of individual cells adn biofilm formation.
Rice is staple food of nearly half the world’s population. Rice yields must therefore increase to feed ever larger populations. By colonising rice and other plants, Herbaspirillum spp. stimulate plant growthand productivity. However the molecular factors involved are largely unknown. To further explore this interaction, the transcription profiles of Nipponbare rice roots inoculated with Herbaspirillum seropedicae were determined by RNA-seq. Mapping the 104 million reads against the Oryza sativa cv. Nipponbare genome produced 65 million unique mapped reads that represented 13,840 transcripts each with at least two-times coverage. About 7.4% (1,014) genes were differentially regulated and of these 255 changed expression levels more than two times. Several of the repressed genes encoded proteins related to plant defence (e.g. a putative probenazole inducible protein), plant disease resistance as well as enzymes involved in flavonoid and isoprenoid synthesis. Genes related to the synthesis and efflux of phytosiderophores (PS) and transport of PS-iron complexes were induced by the bacteria. These data suggest that the bacterium represses the rice defence system while concomitantly activating iron uptake. Transcripts of H. seropedicae were also detected amongst which transcripts of genes involved in nitrogen fixation, cell motility and cell wall synthesis were the most expressed.
Soiling of photovoltaic (PV) systems compromises their performance causing a significant power loss and demanding periodical cleaning actions. This phenomenon raises great concerns in the solar energy field, thus leading to notable research efforts over the last decades. Soiling is caused by a dual action of dust deposition and biofouling. However, surprisingly, the microbiological contribution to PV soiling is often overlooked or underestimated. In this study, a variety of qPCR-based methods have been developed to quantify the microbial load of fungi, bacteria and phototrophs on PV panels. These protocols were evaluated by comparison with culturedependent methods, and were implemented with real solar plants for two years. The results show that the developed molecular methods are highly sensitive and reliable to monitor the microbial component of the soiling. Fungal biomass was clearly dominant in all analysed PV modules, while bacteria and phototrophs showed much lower abundance. Light microscopy and qPCR results revealed that melanised microcolonial fungi and phototrophs are the main biofilm-forming microorganisms on the studied solar panels. In particular, the fungal qPCR protocol is proposed as a useful tool for monitoring of PV soiling, and investigating the microbial contribution to specific soiling cases.
Paragraphs 6 to 8 of the proposed amendment to the German Federal Soil Protection and Contaminated Sites Ordinance contain new requirements regarding the application of soil-like material outside of a rootable soil layer. For example, it is intended to enable reusing of soil-like materials containing regulated substances in concentrations between the single and double precautionary values (PV), provided that the limit values for the eluate are complied with. The aim of a running project (funding code UFOPLAN 3716 74 203 0, German Federal Environmental Agency) is to fill data deficits for soil-like materials which meet the above-mentioned criteria to promote circular economy and conservation of natural resources. Different soil-like materials of various origin (for example dredged material, banquet peeling material, urban and meadow soils) are considered with a special focus on PAHs. A major challenge in sample acquisition is the relatively narrow target range of the PAH content between 3 and 6 mg/kg dm considering a high measurement uncertainty at this concentration level.
The contents of PAHs, heavy metals and other inorganic elements in solid matter are determined following established standards. In addition, the soil-like materials are characterized concerning particle size, pH, conductivity, SOM, TOC and carbonate content. To determine the eluate concentration, column tests according to DIN 19528 and batch tests according to DIN 19529 at a liquid/solid ratio (L/S) of 2 l/kg and 10 l/kg are performed comparatively.
The results show that the new requirements of the planned amendment to the Federal Soil Protection and Contaminated Sites Ordinance certainly opens additional possibilities for reuse of soil-like materials. Even most soil-like materials within 2-3 x PV comply with the eluate value for PAH (0.2 μg/l) both in the batch test and in the column test at L/S 2 l/kg. Selected inorganic substances lead to similar evaluations. Therefore, the application of such soil-like materials outside of rootable soil layers would be possible. Previously, those materials were often used for landfill construction. In the future, a utilization in the adjacent environment by backfilling, recultivation, renaturation, composting or landscaping would be conceivable.
Monodisperse iron oxide nanoparticles as reference material candidate for particle size measurements
(2020)
In order to utilize and rationally design materials at the nanoscale the reliable characterization of their physico-chemical properties is highly important, especially with respect to the assessment of their environmental or biological impact. Furthermore, the European Commission’s REACH Regulations require the registration of nanomaterials traded in quantities of at least 1 ton. Powders or dispersions where 50% (number distribution) of the constituent particles have sizes ≤ 100 nm in at least one dimension are defined as nanomaterials. This creates a need for industrial manufacturers and research or analytical service facilities to reliably characterize potential nanomaterials. Currently, BAM is developing reference nanoparticles, which shall expand the scarce list of worldwide available nano reference materials certified for particle size distribution and will also target other key parameters like shape, structure, porosity or functional properties. In this respect, materials like iron oxide or titanium dioxide are considered as candidates to complement the already available silica, Au, Ag, and polystyrene reference nanoparticles.
The thermal decomposition of iron oleate precursors in high boiling organic solvents can provide large quantities of iron oxide nanoparticles that can be varied in size and shape.[1, 2] The presence of oleic acid or other hydrophobic ligands as capping agents ensures stable dispersion in nonpolar solvents. Such monodisperse, spherical particles were synthesized at BAM and pre-characterized by electron microscopy (TEM, SEM including the transmission mode STEM-in-SEM) and dynamic light scattering comparing cumulants analysis and frequency power spectrum.
1. REACH regulations and nanosafety concerns create a strong need for nano reference materials with diverse properties.
2. Iron oxide nanoparticles are under development as new candidate reference material at BAM.
3. Narrow particle size distribution confirmed by light scattering and electron microscopy.
Mussel-inspired multifunctional coating for bacterial infection prevention and osteogenic induction
(2021)
Bacterial infection and osteogenic integration are the two main problems that cause severe complications after surgeries. In this study, the antibacterial and osteogenic properties were simultaneously introduced in biomaterials, where copper nanoparticles (CuNPs) were generated by in situ reductions of Cu ions into a mussel-inspired hyperbranched polyglycerol (MI-hPG) coating via a simple dip-coating method. This hyperbranched polyglycerol with 10 % catechol groups’ modification presents excellent antifouling property, which could effectively reduce bacteria adhesion on the surface. In this work, polycaprolactone (PCL) electrospun fiber membrane was selected as the substrate, which is commonly used in biomedical implants in bone regeneration and cardiovascular stents because of its good biocompatibility and easy post-modification. The as-fabricated CuNPs-incorporated PCL membrane [PCL-(MI-hPG)-CuNPs] was confirmed with effective antibacterial performance via in vitro antibacterial tests against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and multi-resistant E. coli. In addition, the in vitro results demonstrated that osteogenic property of PCL-(MI-hPG)-CuNPs was realized by upregulating the osteoblast-related gene expressions and protein activity. This study shows that antibacterial and osteogenic properties can be balanced in a surface coating by introducing CuNPs.
Wood treated with nano metal fluorides is found to resist fungal decay. Sol−gel synthesis was used to synthesize MgF2 and CaF2 nanoparticles. Electron microscopy images confirmed the localization of MgF2 and CaF2 nanoparticles in wood. Efficacy of nano metal fluoride-treated wood was tested against brown-rot fungi Coniophora puteana and Rhodonia placenta. Untreated wood specimens had higher
mass losses (∼30%) compared to treated specimens, which had average mass loss of 2% against C. puteana and 14% against R. placenta, respectively. Nano metal fluorides provide a viable alternative to current wood preservatives.
A brief perspective of BAM on nanocarriers is presented including examples with special emphasis on the characterization of such materials and underlying challenges. In this respect, also ongoing activities at BAM on different types of core/shell nanomaterials and related systems are briefly summarized.
In 1981 the OECD published the Test Guideline on Particle size and size distribution. This TG is still a valid document for the measurement of particles all over the world.
When nanomaterials gained importance, ISO set up a technical commitee for Nanotechnologies in 2005 and the OECD followed this step in 2006 with the Working Party on Manufactured Nanomaterials.
In the following years ISO and OECD published several documents about nanomaterials and the systematisation developed.
In 2017 it was finally clear that nanomaterials need to be adressed in another way than chemicals and in 2020 ECHA revised the REACH-Annexes accordingly and included nanomaterials.
Unfortunately there is a little problem with this: Only a few applicable test guidelines exit for the measurement of the nanomaterials. Several test guidelines date from 1981 and do not address nanomaterials.
The logical next step for the OECD would be to publish a series of test guidelines which are indeed currently prepared and will be shown in this talk.
Finally there is an additional need for the future of NM standardisation: Digitalisation.
Microbiologically influenced corrosion (MIC) is a crucial issue for industry and infrastructure. Biofilms are known to form on different kinds of surfaces such as metal, concrete, and medical equipment. However, in some cases the effect of microorganisms on the material can be negative for the consistency and integrity of the material. Thus, to overcome the issues raised by MIC on a system, different physical, chemical, and biological strategies have been considered; all having their own advantages, limitations, and sometimes even unwanted disadvantages. Among all the methods, biocide treatments and antifouling coatings are more common for controlling MIC, though they face some challenges. They lack specificity for MIC microorganisms, leading to cross-resistance and requiring higher concentrations. Moreover, they pose environmental risks and harm non-target organisms. Hence, the demand for eco-friendly, long-term solutions is increasing as regulations tighten. Recently, attentions have been directed to the application of nanomaterials to mitigate or control MIC due to their significant antimicrobial efficiency and their potential for lower environmental risk compared to the conventional biocides or coatings. Use of nanomaterials to inhibit MIC is very new and there is a lack of literature review on this topic. To address this issue, we present a review of the nanomaterials examined as a biocide or in a form of a coating on a surface to mitigate MIC. This review will help consolidate the existing knowledge and research on the use of nanomaterials for MIC mitigation. It will further contribute to a better understanding of the potential applications and challenges associated with using nanomaterials for MIC prevention and control.
Pseudomonas fluorescens (Gram-negative) bacteria purchased from Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures were analyzed using high-resolution x-ray photoelectron spectroscopy at near ambient pressure conditions (NAP-XPS), 1500 Pa water vapor atmosphere. Fresh layers of P. fluorescence bacteria were grown on Luria Broth agar plates. Bacteria were taken from the agar plate with a sterile spatula and gently spread on a Si-wafer piece for NAP-XPS analysis. The NAP-XPS spectra of the bacterial envelope of P. fluorescence were obtained using monochromatic Al Kα radiation and include a survey scan and high-resolution spectra of C 1s, N 1s, P 2p, and O 1s as well. The presentation of the C 1s high-resolution spectrum includes the results of peak fitting analysis.
Natural building materials for interior fitting and refurbishment - What about indoor emissions?
(2021)
Indoor air quality can be adversely affected by emissions from building materials, consequently having a negative impact on human health and well-being. In this study, more than 30 natural building materials (earth dry boards and plasters, bio-based insulation materials, and boards made of wood, flax, reed, straw, etc.) used for interior works were investigated as to their emissions of (semi-) volatile organic compounds ((S)VOC), formaldehyde, and radon. The study focused on the emissions from complete wall build-ups as they can be used for internal Partition walls and the internal insulation of external walls. Test chambers were designed, allowing the compounds to release only from the surface of the material facing indoors under testing Parameters that were chosen to simulate model room conditions. The emission test results were evaluated using the AgBB evaluation scheme, a procedure for the health-related evaluation of construction products and currently applied for the approval of specific groups of building materials in Germany.
Seventeen out of 19 sample build-ups tested in this study would have passed this scheme since they generally proved to be low-emitting and although the combined emissions of multiple materials were tested, 50% of the measurements could be terminated before half of the total testing time.
This application note presents how EnviroESCA can be used to analyze E. coli biofilms on silicon under near ambient pressure conditions in various states of hydration. Such investigations of the outer bacterial cell surface in their hydrated state are essential for studying biological interfaces at work.
Most of our knowledge on insect cuticular hydrocarbons (CHCs) stems from analytical techniques based on gas-chromatography coupled with mass spectrometry (GC-MS). However, this method has its limits under standard conditions, particularly in detecting compounds beyond a chain length of around C40. Here, we compare the CHC chain length range detectable by GC-MS with the range assessed by silver-assisted laser desorption/ionization mass spectrometry (Ag-LDI-MS), a novel and rarely applied technique on insect CHCs, in seven species of the order Blattodea. For all tested species, we unveiled a considerable range of very long-chain CHCs up to C58, which are not detectable by standard GC-MS technology. This indicates that general studies on insect CHCs May frequently miss compounds in this range, and we encourage future studies to implement analytical techniques extending the conventionally accessed chain length range. Furthermore, we incorporate 3D scanned insect body surface areas as an additional factor for the comparative quantification of extracted CHC amounts between our study species. CHC quantity distributions differed considerably when adjusted for body surface areas as opposed to directly assessing extracted CHC amounts, suggesting that a more accurate evaluation of relative CHC quantities can be achieved by taking body surface areas into account.
Healthy and energy efficient buildings must be free from disturbing odours. Odour emissions from building materials can be measured with the well-known and accepted standard ISO 16000-28 “Indoor air – Part 28: Determination of odour emissions from building products using test chambers”. For commonly used emission test chambers the sample air is collected in containers (bags) and presented to a group of panel members for the purpose of evaluating the odour. A standard sets requirements for the on-demand presentation in detail. These include the validation procedure for container materials, pre-treatment of bags, details on storage of filled bags and how to carry out the measurements. However, although these measures are proven in practice, incorrect measurements are still possible. Also errors can occur due to a very complex measurement procedure. So, there is a great need for research into how the odour samples are presented.
The proposal planned to be presented will introduce a new development in sample provision by using an adapter which enables collection and provision of sample air without storage or transport of bags. The adapter is a sample container which is permanently positioned on the emission test chamber´s outlet and continuously filled with sample air flowing through it. The flow is briefly interrupted at the time when a sample is taken by a panel member for the test.
The size of the container is sufficient to provide enough sample air for evaluation by at least one panel member via a funnel. Since sampling and presentation are technically connected, it means you can almost do away with storage or transportation and thus it can be presented almost unchanged to the panelmembers. The aim is to reduce measurement errors in the odour samples provision process and the improvement of measurement reproducibility. The paper presents the construction of the adapter as well as the results of emission and odour tests carried out so far.
This work presents the non-destructive spectroscopic characterisation of original Dead Sea Scrolls (DSS)parchment fragments from Ronald Reed collection. The fragments are of paramount importance becausethey have never been subjected to any treatment of preservation and restoration, this allows to investi-gate the manufacturing method of real original Jewish parchments. The manufacture of “sacred” Jewishparchments, in fact, is traditionally supposed to use a superficial tannin treatment. To study the DSS frag-ments, it was necessary both to analyse mock-up samples, especially manufactured in order to reproduceancient Oriental Jewish ritual parchments, and to compare the results with those obtained in the analysisof modern and ancient Western Jewish ritual parchments, in order to test the effectiveness of the selectedspectroscopic techniques. Traditionally, the main difference between Oriental and Western traditionalparchment preparation consisted in the dehairing method: enzymatic for Oriental and lime-based forWestern. Moreover, a finishing treatment with tannin was supposed to be applied on ritual Jewish parch-ments. The need of reference samples derives from the knowledge that each parchment preparation,treatment and degradation can induce structural modifications that affect the spectral features. FourierTransform Infrared Spectroscopy by Attenuated Total Reflection (ATR-FTIR), FT-Raman and m-Ramanwere used in this study. The experimental results allowed us to recognise, with different sensitivity, thepresence of tannin by using m-Raman and IR spectroscopies and to prove that not all the archaeologicalsamples were manufactured in the same way with vegetal extracts. Many salts (tschermigite, dolomite,calcite, gypsum and iron carbonate) were found on the surface of DSS fragments. They can derive fromthe degradation processes and storage environment before the discovery or from the manufacture. More-over, the different sensitivities and instrumental characteristics of the used techniques permitted us toestablish an analytical protocol, useful for further studies of similar materials.
In order to protect natural gypsum deposits and to compensate for the decreasing amount of Flue Gas Desulfurization (FGD) gypsum it is necessary to develop and explore new sources of gypsum. For this purpose, the potentials of different gypsum wastes are investigated in the study “GipsRec 2.0”, funded by the Federal Ministry of Education and Research (Germany).
On the one hand, the project worked on a new processing technology for gypsum fiberboards (GFB). While the recycling of gypsum plasterboards has already been carried out on an industrial scale for several years, the recycling of gypsum fiberboards (GFB) has proven to be challenging. Gypsum fiberboards from demolition sites and offcuts from GFB production were used for these investigations. The tests were conducted on a technical scale. Furthermore, various synthetic gypsums are being investigated with regard to their suitability for gypsum production. The analyses are carried out on production residues.
In this project, a promising process for gypsum fiberboard recycling could be developed, as well as other waste gypsums are investigated and evaluated with regard to their potential as secondary raw material. In addition, selected process routes are assessed for their environmental impact using a life cycle assessment (LCA) approach.
For centuries, churches, secular buildings and museums have been furnished with valuable works of art. Many works of art are UV- and light-sensitive. It is well known that especially UV radiation causes damage and discoloration in paintings, textiles, plastics, wood and other materials. In particular, the wavelengths between 280 and 410 nm cause color changes, embrittlement or destruction of e.g. plastics over time. Therefore, strongly UV-absorbing glasses are advantageous for architecture and are necessary for the protection of cultural assets. As restorers in all disciplines become more and more aware, the demands placed on buildings and their furnishings in terms of climate are becoming increasingly detailed and precise. The aim in each case is to preserve the valuable artwork.
For some years now, the industry has been offering the protection of cultural objects by installing special UV-protective glasses. Currently, UV protection for church buildings is realized by laminated safety glass equipped with appropriate UV-protective plastic films. Technically, this always means a second pane of glass in front of the windows, which is installed outside the building. This creates climatic gaps that are difficult to control and deterioration due to ageing effects can be expected. At the same time, this protective glazing is not invisible and has a considerable aesthetic influence on the interior and exterior appearance of the building. Meanwhile, the preservation of historical monuments accepts such aesthetic cuts on buildings in order to protect the artwork in the interior from UV light. To this day, however, the long-term durability of UV protection provided by inserted plastic films is still controversial.
To date the only available alternative on the market is a mouth-blown UV protection glass which uses a so-called overlay to provide UV protection. This shows that UV protection can also be achieved by glasses without plastic films thus realizing an exclusive inorganic protection which normally is more stable than a polymeric one. So far there are not enough studies to prove long-term durability.
The aim of this project is to provide existing glazing or new glazing to be created with a highly transparent layer that ensures this UV-protective filter function below 400 nm. The glass coating is to be applied to the glass over a large area and fired into the surface like a classic ceramic enamel paint with the same technics. In addition, it should be long-term durable in its function. It means, that the glass has to be fused at temperatures below 630 °C during the firing process, its chemical durability has to be high, its coefficient of thermal expansion has to be as close as the one of the substrate (usually float glass) and the glass has to absorb the UV-radiation within a thin thickness (thinner as 100 µm).
In this project, the long-term durability of commercial UV-protective glasses is examined. New low melting glasses containing UV-absorbing ions are being developed. Their UV-absorption as a thin layer is analyzed as well as their chemical durability and their thermal properties.
We are grateful to BMWI for the financial support in the frame of the Central Innovation Programme for SMEs (ZIM).
The clothes moth Tineola bisselliella is one of a few insects that can digest keratin, leading to the destruction of clothing, textiles and artwork. The mechanism of keratin digestion is not yet fully understood, partly reflecting the lack of publicly available genomic and transcriptomic data. Here we present a high-quality gut transcriptome of T. bisselliella generated from larvae reared on keratin-rich and keratin-free diets. The overall transcriptome consists of 428,221 contigs that were functionally annotated and screened for candidate enzymes involved in keratin utilization. As a mechanism for keratin digestion, we identified cysteine synthases, cystathionine β-synthases and cystathionine γ-lyases. These enzymes release hydrogen sulfite, which may reduce the disulfide bonds in keratin. The dataset also included 27 differentially expressed contigs with trypsin domains, among which 20 were associated with keratin feeding. Finally, we identified seven collagenases that were upregulated on the keratin-rich diet. In addition to this enzymatic repertoire potentially involved in breaking down keratin, our analysis of poly(A)-enriched and poly(A)-depleted transcripts suggested that T. bisselliella larvae possess an unstable intestinal microbiome that may nevertheless contribute to keratin digestion
Industrial and agricultural waste streams (waste water, sludges, tailings, etc.) which contain high concentrations of NH4+, PO43–, and transition metals are environmentally harmful and toxic pollutants. At the same time, phosphorous and transition metals constitute highly valuable resources. Typically, separate pathways have been considered to extract hazardous transition metals or phosphate independently from each other. Investigations on the simultaneous removal of multiple components have been carried out only to a limited extent. Here, we report the synthesis routes for Ni- and Co-struvites (NH4MPO4·6H2O, M = Ni2+ and Co2+), which allow for P, ammonia, and metal co-precipitation. By evaluating different reaction parameters, the phase and stability of transition metal struvites as well as their crystal morphologies and sizes could be optimized. Ni-struvite is stable in a wide reactant concentration range and at different metal/phosphorus (M/P) ratios, whereas Co-struvite only forms at low M/P ratios. Detailed investigations of the precipitation process using ex situ and in situ techniques provided insights into the crystallization mechanisms/crystal engineering of these materials. M-struvites crystallize via intermediate colloidal amorphous nanophases, which subsequently aggregate and condense to final crystals after extended reaction times. However, the exact reaction kinetics of the formation of a final crystalline product varies significantly depending on the involved metal cation in the precipitation process: several seconds (Mg) to minutes (Ni) to hours (Co). The achieved level of control over the morphology and size makes precipitation of transition metal struvites a promising method for direct metal recovery and binding them in the form of valuable phosphate raw materials. Under this paradigm, the crystals can be potentially up-cycled as precursor powders for electrochemical or (electro)catalytic applications, which require transition metal phosphates.
Plants and microorganisms, besides the climate, drive nitrogen (N) cycling in ecosystems. Our objective was to investigate N losses and N acquisition strategies along a unique ecosystem-sequence (ecosequence) ranging from arid shrubland through Mediterranean woodland to temperate rainforest. These ecosystems differ in mean annual precipitation, mean annual temperate, and vegetation cover, but developed on similar granitoid soil parent material, were addressed using a combination of molecular biology and soil biogeochemical tools. Soil N and carbon (C) contents, δ15N signatures, activities of N acquiring extracellular enzymes as well as the abundance of soil bacteria and fungi, and diazotrophs in bulk topsoil and rhizosphere were determined. Relative fungal abundance in the rhizosphere was higher under woodland and forest than under shrubland. This indicates toward plants' higher C investment into fungi in the Mediterranean and temperate rainforest sites than in the arid site. Fungi are likely to decompose lignified forest litter for efficient recycling of litter-derived N and further nutrients. Rhizosphere—a hotspot for the N fixation—was enriched in diazotrophs (factor 8 to 16 in comparison to bulk topsoil) emphasizing the general importance of root/microbe association in N cycle. These results show that the temperate rainforest is an N acquiring ecosystem, whereas N in the arid shrubland is strongly recycled. Simultaneously, the strongest 15N enrichment with decreasing N content with depth was detected in the Mediterranean woodland, indicating that N mineralization and loss is highest (and likely the fastest) in the woodland across the continental transect. Higher relative aminopeptidase activities in the woodland than in the forest enabled a fast N mineralization. Relative aminopeptidase activities were highest in the arid shrubland. The highest absolute chitinase activities were observed in the forest. This likely demonstrates that (a) plants and microorganisms in the arid shrubland invest largely into mobilization and reutilization of organically bound N by exoenzymes, and (b) that the ecosystem N nutrition shifts from a peptide-based N in the arid shrubland to a peptide- and chitin-based N nutrition in the temperate rainforest, where the high N demand is complemented by intensive N fixation in the rhizosphere.
Per- and polyfluoroalkyl substances (PFAS) are widely used for durable water-repellent finishing of different fabrics and textiles like outdoor clothing, carpets, medical textiles and more. Existing PFAS extraction techniques followed by target analysis are often insufficient in detecting widely used side-chain fluorinated polymers (SFPs) that are barely or non-extractable. SFPs are typically copolymers consisting of a non-fluorinated backbone with perfluoroalkyl side-chains to obtain desired properties. We compared the accessible analytical information and performance of complementary techniques based on oxidation (dTOP assay, PhotoTOP), hydrolysis (THP assay), standard extraction, extractable organic fluorine (EOF), and total fluorine (TF) with five functional textiles and characterized 7 further textiles only by PhotoTOP oxidation. The results show that when applied directly to textile samples, oxidation by dTOP and PhotoTOP and also hydrolysis by the THP are able to capture large fractions of the TF in form of perfluoroalkyl side-chains present in the textiles while methods relying on extracts (EOF, target and non-target analysis) were much lower (e.g., factor ~25-50 lower). The conversion of large fractions of the measured TF into PFCAs or FTOHs from fluorinated side chains is in contrast to previous studies. Concentrations ranged from <LOQ to over ~1000 mg F/kg after oxidation/hydrolysis and <LOQ to over 2000 mg F/kg for TF, while EOF and target PFAS in extracts were detected at much lower concentrations (up to ~ 60 mg F/kg) (amount of fluorine in the order: extraction << EOF << oxidation/hydrolysis ≤ TF). Perfluoroalkyl carboxylic acids (PFCAs) and fluorotelomer alcohols (FTOHs) from THP and PhotoTOP both represented the chain-length distribution in the textiles showing that long-chain SFPs are still used in current textiles. Further advantages and disadvantages of the applied methods are discussed.
Physico-chemical analyses of writing materials offer insight into various questions associated with historical, cultural, and conservational aspects of manuscript studies. The catalogue of questions that can be addressed with these methods includes authenticity, dating, the attribution of various parts of the text to different scribes and the relation between the primary and secondary texts. Similarly, preservation of the manuscripts requires knowledge of the composition of the original materials versus old repairs, identification of damage, as well as recognition of natural aging and degradation processes. The material sciences can contribute data about the chemical compositions of the writing materials, elucidation of the techniques of their production and the absolute age of organic components, as well as characterization of corrosion effects, evaluation of conservation treatment, and monitoring of the preservation state.
This thesis addresses the development of a methodological approach for the non-invasive identification of colourants and for the classification of binding media in reverse glass paintings from the early 20th century. For this purpose, mobile and miniaturized devices were used to measure the paintings in situ. The methodology includes X-ray fluorescence (XRF), VIS spectroscopy (VIS), Raman spectroscopy and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). In a first step the capabilities of DRIFTS for binding media classification and pigment identification were tested.
DRIFTS enables, besides Raman spectroscopy, the collection of molecular information of a substance that can be used as characteristic fingerprint spectrum. However, the simultaneous collection of both specular (surface) and diffuse (volume) reflection leads to complicated mixed DRIFT spectra, that can vary strongly for one substance depending on the dominant fraction of reflected light. Specular reflection causes several spectral distortions like inverted bands, band shifts and derivative-like features whereas pure diffuse reflections leads to an intensity enhancement of combination bands and overtones. Both specular and diffuse reflection cannot be optically separated, and their proportion depends on material properties like the absorption coefficient and the refractive index as well as on Parameters like surface roughness, porosity, grain size and angle of incidence and detection. A direct comparison of DRIFT spectra with IR spectra of other methods (e.g. transmission, ATR) is not possible, hence the creation of DRIFTS databases was needed. The next step was the complimentary utilization of Raman spectroscopy and DRIFTS for the dentification of synthetic organic colourants. Such colourants are in the further chapters called synthetic organic pigments (SOP) even when it’s not always entirely clear if they are soluble dyes or pigments that are practically insoluble in the medium in which they are incorporated. Raman spectroscopy is generally the method of choice when dealing with SOP, but fluorescence can hamper the Raman spectrum severely, inhibiting the proper identification of the pigment.
DRIFTS was successfully applied and several SOP like synthetic alizarin (PR83), the yellow azo pigments (e.g. PY1) or the red and orange β-naphthol pigments (e.g. PR3) could be identified in the paintings solely by means of DRIFTS. The holistic methodological sequence was defined after the successful establishment of DRIFTS as serious analytical alternative. As the time is always the most limiting factor for in situ measurement campaigns in museums, the 9
sequence needs to be time saving but also efficient. The methodology starts with quick measurements by XRF and VIS to get a first idea of the pigment composition, followed by the validation of the results with the vibrational spectroscopies for selected points.
Measurements of reverse glass paintings by Carlo Mense and Wassily Kandinsky were conducted to test the entire procedure. A high number of pigments could be identified, including several rare ones like strontium white (SrSO4), PR60 and PB52. The binding media were classified using the previously recorded references. The results were set in the art historian context and were discussed in a multidisciplinary way. The influence of Asian art, especially of Chinese reverse glass paintings as source of inspiration for artists of the “Blauer Reiter” collective (e.g. Wassily Kandinsky, Gabriele Münter, Franz Marc und Heinrich Campendonk) is shown. Non-invasive measurements of two Chinese reverse glass paintings from the late 19th and early 20th century were conducted, enabling a comparison of the palettes of Chinese and European painters. The Chinese palette includes heavy use of red lead and orpiment, pigments that were hardly sed in Europe anymore. More modern pigments like zinc white, cadmium yellow, viridian, chromates, cobalt blues or SOP were not found at all in the Chinese paintings.
In a rapidly evolving world, the demand on raw materials is increasing steadily and many technologies are dependent on a secure supply of hi-tech metals. Recently, scandium (Sc) has attracted attention since its use in high strength Al-alloys and solid-oxide-fuel-cells strongly improves the performance of those materials.
The element Sc is not exceptionally rare but quite resistant to geochemical enrichment processes, it is scarcely found enriched to high concentrations and is recovered as a by-product. Since Sc enrichment in Greek bauxite residues was shown by Ochsenkühn-Petropoulou et. al (1994), intensive research on this material and development of efficient Sc-recovery methods is ongoing.
This study investigates Sc-bearing species in bauxite residues from alumina production. It aims to provide direct evidence about the Sc-speciation’s in those secondary resources and tries to find the link to speciation’s in primary resources, e.g. bauxites and laterites.
Therefore, Sc K edge XANES (X-ray absorption near edge structure) spectroscopy is performed using synchrotron radiation to determine the presence of certain Sc-components and distinguish between adsorbed and chemically bonded Sc as was shown for lateritic deposits in Australia by Chassé et al. 2016. For comparison, reference standards of Sc-bearing and Sc-adsorbed species are synthesized. Indirect inferences from leaching behavior of bauxites, in cases supported by analyses with LA-ICP-MS, suggest Sc to be associated with either iron- or aluminum phases (Vind et al. 2017); (Suss et al.). It remains unclear how different primary materials influence Sc-speciation in the bauxite residue. Therefore, a comparison between different European bauxite residues is made in this study. The investigations should help to understand Sc chemistry and
behavior in different primary and secondary materials and provide fundamentals for metallurgical processing. The research is incorporated in the SCALE project (GA No. 730105) funded by EU Horizon 2020 research and innovation program.
MFC was used to study the corrosiveness of iron-utilizing methanogen, Methanobacterium IM1 under flow conditions. Comparing against electrical SRM, Desulfovibrio ferrophilus IS5, results showed under standard mesophilic conditions, average corrosion rates of Methanobacterium IM1 was double that of SRM. The highest corrosion rate of Methanobacterium IM1 reached up to 0.60 mm/yr under neutral conditions, and severe pitting was observed on the iron surface. Furthermore, the corrosion products of Methanobacterium IM1 were characterized with TOF-SIM, FIB-SEM and EDX, and preliminary results revealed FeCO3 is not the only corrosion product of Mi-MIC, as previously reported. Under low pH conditions, the maximum corrosion rate of Methanobacterium IM1 reached 1.57 mm/yr, which resulted in severed deformity of the iron specimen. Additional comparisons using different types of incubation material were conducted to standardize MFC MIC testing.
Timber is constantly exposed to environmental influences under outdoor conditions which limits its Lifetime and usability. In order to counteract the damaging processes caused by insects, we have developed a novel and more environmentally friendly method to protect wood materials via covalent modification by organic insecticides. Starting with an important class of synthetic insecticides which are derived from the natural insecticide nicotine, various new carboxylic acid derivatives of imidacloprid were made accessible. These activated neonicotinoids were utilized for the chemical modification of wood hydroxy groups. In contrast to conventional wood preservation methods in which biocides are only physically bound to the surface for a limited time, the covalent fixation of the preservative guarantees a permanent effect against wood pests, demonstrated in standardized biological tests. Additionally, the environmental interaction caused by non-bound neonicotinoids is significantly reduced, since both, a smaller application rate is required and leaching of the active ingredient is prevented. By minimizing the pest infestation, the lifetime of the material increases while preserving the natural appearance of the material.
Condensation particle counters (CPCs) are widely used for the measurement of aerosol particle number concentrations in the size range from approximately 3 nm to 3 μm. For an SI-traceable calibration of the size-dependent counting efficiency, which is advisable on a regular basis and required in several applications, Faraday cup aerosol electrometers (FCAEs) are considered to be a suitable SI-traceable reference.While the volumetric aerosol inlet flowrate and the electrical current measurement in FCAEs can be related to respective SI references, inter-comparison exercises for FCAEs are still performed on a regular basis to establish reliable uncertainty budgets and to further investigate the influences of designs and operational parameters on comparability. This is strongly demanded in the international community of metrological institutes and aerosol calibration facilities around the world, which provide CPC calibrations. In the present study, the performance of FCAEs was investigated,using Ag test aerosol particles with a 30 nm particle diameter by varying the inlet flowrates from 0.5 l min−1 to 4 l min−1. From our experimental results, significant deviations were observed in FCAE currents at sample flowrates smaller than 1.5 l min−1. It is recommended that these discrepancies should be quantified before an FCAE is used for CPC calibration at low sample flowrates and small particle sizes in the sub-30 nm size range.
One criterion to evaluate the odour of a sample is perceived
intensity П which is evaluated with the aid of a comparative scale. The procedure is well accepted but also time consuming and extensive. The study should help simplify the testing procedure by asking the panel members to only indicate whether a sample is perceived as less to equally intense or of greater intensity in comparison to a given acetone concentration of 7 pi on the comparative scale. In Germany a value of 7 pi is required for products to be suitable for the indoor use. The results show that the simplified test is basically suitable.
VOC-emissions and their odours from building products and furnishings present indoors should not have an impact on personal well-being or health. Odours can be measured by applying the standard ISO 16000-28. Indoor air determination of odour emissions from building products using test chambers. One of the described procedures is the assessment of perceived intensity using a comparative scale by a group of panellists. In this paper, the perceived intensity sampling procedure and its evaluation method are investigated and shown to need improvement. New technical developments in the methodology used to increase the reproducibility of measurement results are discussed. Since odour tests are used for labelling, they have a major influence on the assessment of construction products, similar to the procedure of the German Committee for Health Evaluation of Building Products (AgBB). In the original ISO standard, the evaluation is typically performed using a sampling container separated from the emission chamber. For a better sample presentation, an adapter was developed to connect the emission test chamber to the evaluation funnel and thus enable an odour assessment which is comparable to a direct measurement. The investigations show that losses of odourous substances can be greatly reduced, which is very desirable when seeking to obtain reliable results in odour measurement. Another experimental series was carried out to reduce the measurement effort in the evaluation of perceived intensity. Application of the developed greater than or less than/equal to. query could be helpful here. The results show that the query mostly leads to the same result as the evaluation of the perceived intensity using the method according to the standard but is much easier to perform. Overall, the results can contribute to improving the acceptance of the evaluation of perceived intensity using ISO 16000-28 and to determining odours from building materials increasingly more precisely.
The new OECD test guideline will address the following four main steps in the determination of the length and width distributions of fibers: sample preparation, image acquisition, data evaluation and uncertainty analysis. As the sample preparation has to be optimized for each material, general quality criteria will be given in the protocol. For full visibility of a fiber the appropriate resolution has to be chosen. In the data evaluation the length and diameter of each fiber will be determined concurrently to allow for application of different regulatory definitions. The quality of the results critically depends on the sample preparation as well as the data evaluation. In this step the classification rules have to be formulated and followed accurately in order to optimize reproducibility of the method. The SOP will be validated in an international round robin test, which is planned for 2018/2019.
The new OECD test guideline will address the following four main steps in the determination of the length and width distributions of fibers: sample preparation, image acquisition, data evaluation and uncertainty analysis. As the sample preparation has to be optimized for each material, general quality criteria will be given in the protocol. For full visibility of a fiber the appropriate resolution has to be chosen. In the data evaluation the length and diameter of each fiber will be determined concurrently to allow for application of different regulatory definitions. The quality of the results critically depends on the sample preparation as well as the data evaluation. In this step the classification rules have to be formulated and followed accurately in order to optimize reproducibility of the method. The SOP will be validated in an international round robin test, which is planned for 2018/2019.
The properties of nanomaterials are influenced not only by their chemical composition but also by physical properties (such as size, geometry and crystal structure). For the reliable determination and assessment of behaviour and effects of nanomaterials as well as for the determination of the exposure of humans and environment a comprehensive physical-chemical characterization of nanomaterials is essential. This is an important prerequisite to identify them as nanomaterials and to interpret and compare test results and - in future – to forecast interaction and effects of nanomaterials.
In 2006, the OECD launched a sponsorship program for the testing of nanomaterials in which 11 nanomaterials were thoroughly investigated using a variety of methods. The aim of the project was, among other things, to find out where problems occur and where there are gaps in the measurement and test procedures and where are changes required. An important outcome of the sponsorship program was the finding that the OECD Test Guidelines should in several cases be extended to the specific needs in testing of nanomaterials. The existing standardized test methods of the OECD for physical-chemical characterization have not been developed for nanomaterials in particular. A high demand for an extension of the test guidelines was identified. Germany complied with the OECD's request in 2017 and has agreed to extend the “Test Guideline on Particle Size Distribution / Fiber Length and Diameter Distributions Test Guideline” for Manufactured Nanomaterials (MN). UBA commissioned BAM and BAuA with the preparation of the Test Guideline. The aim of the project is the development of a harmonized test protocol for a valid and reproducible determination of particle size and size distribution which is one of the most relevant physical-chemical properties for MNs.
Different measuring methods provide different results for the size distribution of the particles. This is caused by the different measuring principles of the methods. Each method measures a specific parameter that ultimately determines particle size. First, the measured quantity differs for each method (Scattered light intensity, 2D image / projection, electric mobility, etc.). Second, the calculated diameters of the MN may differ (Feret Diameter, Area Projection, Mobility Diameter, Aerodynamic Diameter, Hydrodynamic Diameter). Third, a measuring method provides a size distribution which is measured either mass-based, surface-based or number-based. A conversion between the results requires additional parameters and thus possibly increases the measurement error.
In addition to the technical differences, the individual parameters are strongly influenced by the structure and material of the nanoparticles. For example, a surface functionalization can lead to very different results in the size distribution. The suitability of measurement methods differs with the material of the MN. As a result, two very different results can be measured for the particle size distribution using two different methods, which are nevertheless both correct. Several large projects in recent years therefore concluded that nanomaterials should be characterized by at least two complementary method. Imaging techniques are regarded as one of these methods for the characterization, the complementary methods are supposed to be statistical methods.
The different results for the size distribution of nanomaterials become problematic for the registration of new MN. A comparable and reproducible size distribution is a prerequisite for a standardized registration. In the future, the particle size distribution in the EU will also decide on the classification of a substance as a nanomaterial or as a non-nanomaterial. Especially in borderline cases, a standardized and comparable measurement methodology is therefore essential.
The properties of nanomaterials are influenced not only by their chemical composition but also by physical properties (such as size, geometry and crystal structure). For the reliable determination and assessment of behaviour and effects of nanomaterials as well as for the determination of the exposure of humans and environment a comprehensive physical-chemical characterization of nanomaterials is essential. This is an important prerequisite to identify them as nanomaterials and to interpret and compare test results and - in future – to forecast interaction and effects of nanomaterials.
In 2006, the OECD launched a sponsorship program for the testing of nanomaterials in which 11 nanomaterials were thoroughly investigated using a variety of methods. The aim of the project was, among other things, to find out where problems occur and where there are gaps in the measurement and test procedures and where are changes required. An important outcome of the sponsorship program was the finding that the OECD Test Guidelines should in several cases be extended to the specific needs in testing of nanomaterials. The existing standardized test methods of the OECD for physical-chemical characterization have not been developed for nanomaterials in particular. A high demand for an extension of the test guidelines was identified. Germany complied with the OECD's request in 2017 and has agreed to extend the “Test Guideline on Particle Size Distribution / Fiber Length and Diameter Distributions Test Guideline” for Manufactured Nanomaterials (MN). UBA commissioned BAM and BAuA with the preparation of the Test Guideline. The aim of the project is the development of a harmonized test protocol for a valid and reproducible determination of particle size and size distribution which is one of the most relevant physical-chemical properties for MNs.
Different measuring methods provide different results for the size distribution of the particles. This is caused by the different measuring principles of the methods. Each method measures a specific parameter that ultimately determines particle size. First, the measured quantity differs for each method (Scattered light intensity, 2D image / projection, electric mobility, etc.). Second, the calculated diameters of the MN may differ (Feret Diameter, Area Projection, Mobility Diameter, Aerodynamic Diameter, Hydrodynamic Diameter). Third, a measuring method provides a size distribution which is measured either mass-based, surface-based or number-based. A conversion between the results requires additional parameters and thus possibly increases the measurement error.
In addition to the technical differences, the individual parameters are strongly influenced by the structure and material of the nanoparticles. For example, a surface functionalization can lead to very different results in the size distribution. The suitability of measurement methods differs with the material of the MN. As a result, two very different results can be measured for the particle size distribution using two different methods, which are nevertheless both correct. Several large projects in recent years therefore concluded that nanomaterials should be characterized by at least two complementary method. Imaging techniques are regarded as one of these methods for the characterization, the complementary methods are supposed to be statistical methods.
The different results for the size distribution of nanomaterials become problematic for the registration of new MN. A comparable and reproducible size distribution is a prerequisite for a standardized registration. In the future, the particle size distribution in the EU will also decide on the classification of a substance as a nanomaterial or as a non-nanomaterial. Especially in borderline cases, a standardized and comparable measurement methodology is therefore essential.
OECD test guideline on particle size and size distribution: Comparability of measurement results
(2019)
OECD-Prüfrichtlinien werden weltweit für regulatorische Zwecke angewandt, da sie eine harmonisierte und über internationale Ringversuche validierte Vorschrift zur Analyse vorgeben. Die bestehende Prüfrichtlinie TG 110 zur Größencharakterisierung von Partikeln und Fasern ist für viele Methoden und Materialklassen nicht geeignet, weswegen es Bedarf an einer Neuentwicklung gibt. Im Fokus der neuen TG steht die reproduzierbare und vergleichbare Anwendung von Methoden zur Bestimmung von Partikelgröße sowie Größenverteilung annährend sphärischer und faserförmiger Nanomaterialien im Bereich 1-1000 nm. Berücksichtigt werden die häufig angewandten Methoden zur Größencharakterisierung mit ihren unterschiedlichen physikalisch-technischen Limitierungen und die Bestimmung unterschiedlicher Durchmesser (hydrodynamischer, Feret…). Weiterhin sind materialspezifische Einflüsse durch die Partikel sowie das Messmedium zu berücksichtigen. Jede der Methoden soll unter Berücksichtigung von ISO-Standards und den materialspezifischen Limitierungen in der neuen Prüfrichtlinie beschrieben und über einen Ringversuch validiert werden.
The OECD test guidelines (TGs) for testing chemicals have been widely used for regulatory purposes all over the world since the establishment of the Mutual Acceptance of Data (MAD) principle in 1984. This MAD principle ensures that, if a chemical is tested under the Good Laboratory Practice (GLP) conditions accordingly to an OECD TG, the data should be accepted in all OECD countries. The TGs have been developed, harmonized, internationally validated (round robin tests) and adopted by OECD countries to be used for the physical-chemical characterisation, fate estimation, and hazard identification for risk assessment of various chemicals. In addition to the TGs, OECD Guidance Documents (GDs) usually provide guidance on how to use TGs and how to interpret the results. These GDs do not have to be fully experimentally validated, and hence they are not under MAD, but they are based on relevant published scientific research.
But are the existing TGs and the related GDs applicable and adequate for the regulatory testing of nanomaterials? In general, it is accepted that most of the "endpoints" or more precisely measurement variables are applicable also for nanomaterials. However, for some endpoints new or amended TGs are needed. In addition, several GDs are needed to give more precise advice on the test performance in order to gain regulatory relevant data on nanomaterials.
The poster will present the status quo on recent TGs and GDs development for nanomaterials at OECD level with relevance for physical-chemical characterisation. Emphasis will be given to the proposed OECD TG on particle size and size distribution for manufactured nanomaterials. The development of such a TG is of special importance as particle size and size distribution is considered as major information for nanomaterial identification and characterization. A reliable and reproducible characterisation of particle size and size distribution is also needed for chemicals risk assessment of nanomaterials, for instance to interpret and compare test results and - in future – to forecast interaction and effects of nanomaterials. The presented poster will illustrate the way from the idea for a new TG and new GD to an accepted OECD TG/GD.
The OECD test guidelines (TGs) for testing chemicals have been widely used for regulatory purposes all over the world since the establishment of the Mutual Acceptance of Data (MAD) principle in 1984. This MAD principle ensures that, if a chemical is tested under the Good Laboratory Practice (GLP) conditions accordingly to an OECD TG, the data should be accepted in all OECD countries. The TGs have been developed, harmonized, internationally validated (round robin tests) and adopted by OECD countries to be used for the physical-chemical characterisation, fate estimation, and hazard identification for risk assessment of various chemicals. In addition to the TGs, OECD Guidance Documents (GDs) usually provide guidance on how to use TGs and how to interpret the results. These GDs do not have to be fully experimentally validated, and hence they are not under MAD, but they are based on relevant published scientific research.
But are the existing TGs and the related GDs applicable and adequate for the regulatory testing of nanomaterials? In general, for nanomaterials it is accepted that most of the "endpoints" or more precisely measurement variables are applicable. However, for some endpoints new or amended TGs are needed. In addition, several GDs are needed to give more precise advice on the test performance in order to gain regulatory relevant data on nanomaterials.
This presentation was held in an OECD Webinar introducing the newly developed and published OECD TG 125 on particle size and size distribution. The presentation is explaining the structure if the TG 125 and addresses all included methods and methodologies in a short and understandable way for the broader public. The presentation includes sections about nano-particles and nano-fibres.
In arid sun-exposed environments, rock-inhabiting fungi dominate microbial communities on rock surfaces. Fungi are known to enhance rock weathering, although the exact mechanisms are not completely understood. These natural processes can be simulated by reproducible experimental systems. Particularly attractive are genetically amenable rock-weathering fungi, where certain traits can be knocked-out to identify weathering-relevant functions. Here, we studied the effect of the rock-inhabiting fungus Knufia petricola A95 and its melanin-deficient mutant (ΔKppks) on the weathering of a Fe-bearing olivine. We examined the olivine dissolution kinetics and looked at the olivine-fungus interface. For the former we inoculated olivine powder with the fungus in batch and mixed flow reactors and analysed the medium solution by ICP-OES, for the latter biofilm-covered olivine sections from flow-through reactors were analysed by FIB-TEM.
In general olivine dissolution was lower when olivine was incubated without fungi: the abiotic olivine dissolution rates were lowest and the surface of the abiotically reacted olivine sections showed no etching. Various chemical analyses show Fe (oxyhydr)oxide precipitation on top of the abiotically reacted olivine, indicating its role in inhibiting olivine dissolution. Both the wild type (WT) and ΔKppks solubilised and bound significant amounts of Fe released by olivine dissolution. Fe (oxyhydr)oxide precipitation was thus reduced, explaining the enhanced olivine dissolution in their presence. Particularly efficient at preventing Fe precipitation were attached WT cells: the inhibition of olivine dissolution almost completely disappeared. The attachment capacity of the WT is most likely caused by the production of WT-specific extracellular polymeric substances. Our presented experimental systems allowed the precipitation of Fe (oxyhydr)oxides and included a rock-inhabiting fungus and thus simulated weathering processes relevant to natural ecosystems.
Any surface in the environment acts as hotspot for microbial attachment and activity. These biofilms represent the interface between humans and the environment.
While in the past biofilms were often seen as disturbance, we now start to understand the enormous potential of beneficial biofilms. They can be used in a broad range of applications and are sources for new microorganisms and traits. After all, biofilms represent a great example for a collaborative lifestyle.
On the use of Carbograph 5TD as an adsorbent for sampling VVOCs: validation of an analytical method
(2023)
A standardised method for the analysis of very volatile organic compounds (VVOCs) in indoor air is still missing. This study evaluates the use of Carbograph 5TD as an adsorbent for 60 compounds (47 VVOCs + 13 VOCs) by comparing their recoveries with different spiking modes. The influence of the spiking of the tubes in dry nitrogen, humidified air or along the whole flushing duration mimicking real sampling was investigated. 49 substances (36 VVOCs from C1 to C6) had recoveries over 70% on the adsorbent in humidified air and were validated. The linearity of the calibration curves was verified for every spiking mode and the limits of detection (LOD) and quantification (LOQ) were determined. The LOQs were lower than the existing indoor air guideline values. The robustness of the method was considered by studying the influence of the sampling volume, the sampling flow rate, the humidity level and the storage of the tubes. In general, the most volatile or polar substances were the less robust ones. The combined measurement uncertainty was calculated and lies below 35% for a vast majority of the substances. An example of an emission chamber test using polyurethane foam is shown: Carbograph 5TD performs much better than Tenax® TA for VVOCs and emissions from n-butane were quantified with combined measurement uncertainty.
Tantalum and niobium are essential for the development of electronics towards a more and more compact design, but without reducing their performance today. Especially in smart phones and tablets, tantalum and niobium capacitors with high charge densities have already become almost indispensable. However, tantalum as a critical raw material is still a problem for the sustainable production of electronics. Due to this fact, the existence of efficient recycling processes especially in Europe is becoming even more important nowadays.
The Bundesanstalt für Materialforschung und -prüfung (BAM) is currently working on the optimisation of an existing pyrometallurgical tantalum recycling process. Optimisation of this industrial process is carried out in a small-scale electric arc furnace (480 kVA, capacity approx. 150 kg/h) at BAM using a new and innovative equipment for on-line analysis of high temperature processes.
The aim of this project is to identify the best timing for an optimum slag tapping, when the slag is lower than minimum targeted tantalum concentration. Hence, LIBS (Laser induced breakdown spectroscopy) is used to identify the chemical composition of the slag layer and during slag tapping. The on-line-LIBS prototype of BAM enables an in-situ measurement of the element distribution in the melt after calibration on the slag system.
First results of this joint research project will be presented including on-line-LIBS-measurements and thermodynamic and kinetic aspects of the process.
Tantalum and niobium are essential for the development of electronics towards a more and more compact design, but without reducing their performance today. Especially in smart phones and tablets, tantalum and niobium capacitors with high charge densities have already become almost indispensable. However, tantalum as a critical raw material is still a problem for the sustainable production of electronics. Due to this fact, the existence of efficient recycling processes especially in Europe is becoming even more important nowadays.
The Bundesanstalt für Materialforschung und -prüfung (BAM) is currently working on the optimisation of an existing pyrometallurgical tantalum recycling process. Optimisation of this industrial process is carried out in a small-scale electric arc furnace (480 kVA, capacity approx. 150 kg/h) at BAM using a new and innovative equipment for on-line analysis of high temperature processes.
The aim of this project is to identify the best timing for an optimum slag tapping, when the slag is lower than minimum targeted tantalum concentration. Hence, LIBS (Laser induced breakdown spectroscopy) is used to identify the chemical composition of the slag layer and during slag tapping. The on-line-LIBS prototype of BAM enables an in-situ measurement of the element distribution in the melt after calibration on the slag system.
First results of this joint research project will be presented including LIBS-measurements and thermodynamic and kinetic aspects of the process.
Abstract: Since it is unknown for many applications, which PFASs are used and how they enter the environment, target analysis-based methods reach their limits. The two most frequently used sum parameters are the adsorbable organically bound fluorine (AOF) and the extractable organically bound fluorine (EOF). Both can be quantified using either combustion ion chromatography (CIC) or high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS). Here we provide an insight on the advantageous and disadvantageous of both sum parameters and both detection methods. Our study is based on the analysis of surface water samples. Next to total fluorine (TF) analysis, AOF and EOF were determined as well as CIC and HR-CS-GFMAS are compared and results are comparatively discussed. Fluorine mass balancing revealed that, the AOF/TF proportion was higher than the EOF/TF proportion. The AOF made up 0.14–0.81% of TF and the EOF 0.04–0.28% of TF. Although, organically bound fluorine represents only a small portion of TF, PFASs are of worldwide concern, because of their extreme persistence and their bioaccumulation potential. The EOF-HR-CS-GFMAS method turned out to be more precise and sensitive than the AOF-CIC method and is a promising tool for future monitoring studies/routine analysis of PFASs in the environment.
The manuscript Codex germanicus 1 (Cod. germ. 1) of the Staats- und Universitätsbibliothek Hamburg is a fifteenth-century German-language manuscript. It comprises two codicological units and has an especially complex developmental history. To trace this developmental history, neglected until now in the research literature, the manuscript was investigated, for the first time not solely with classical codicological and palaeographical methods, but also with the aid of X-ray fluorescence spectroscopy, in order to determine the composition of the writing materials. These methods made it possible, first, to support and check palaeographic findings and, second, to gain information about the stratigraphy of the manuscript where palaeographic methods find their limits – in regard to short entries, rubrications, and non-alphabetical signs.
The lecture traces the origins of paper, the manufacture and the spread from China to the Middle East and Europe.
Though technological progress considerably affected each step of the manufacture of paper, the essence of the invention remains unchanged until today. The process of manufacturing handmade paper can be divided into a number of steps:
- choosing the raw material (e.g. cellulose from wood, cotton, rags)
- beating and grinding the fibres into small pieces
- producing a liquid pulp of the desired texture
- treating the pulp with various additives
- filling the pulp suspension into a paper mould
- draining the water
- pressing and drying to get the actual sheet
- various post-production treatments
We will see how the manufacturing process is reflected in the properties of the paper and its degradation. A special attention will be paid to the instrumental analysis for identification of the paper types. Also watermark play an important role in the studies of the manuscripts. A short overview will be offered at the ends of the lecture.
Parchment
(2019)
This lecture will present history of parchment based on written sources and chemical examination of antique, medieval and modern parchment.
Our studies of the Dead Sea Scrolls writing surfaces show that they can be divided roughly into three groups: leather, parchments of a light tint, and those of various shades of brown. The latter ones are invariably tanned, whereas the middle group is characterized by the presence of various inorganic salts. Some of the pale parchments, among them the Temple Scroll (11Q19), are remarkably similar to medieval European parchment. Therefore we have formulated the working theory that in the Judaea of the Hellenistic period two different parchment-making traditions existed side by side: an ‘eastern’ one (represented by the tanned parchments of Qumran, closely resembling Aramaic documents from the fifth century BC, and a ‘western’ one (represented by the untanned/lightly tanned ones similar to early Christian Greek parchments).
This division has found support during our studies of the Geniza fragments, in which Babylonian and Palestinian traditions seem to follow the “eastern” and “western” technologies, respectively.
Per- and polyfluoroalkyl substances (PFAS) are chemicals which were developed to improve humanity’s quality of life. Due to their high chemical stability and resistance to degradation by heat or acids, PFAS were used in a variety of consumer products. The continuous use of PFAS in household products and the discharge of PFAS from industrial plants into the sewer system resulted in the contamination of effluents and sewage sludge from wastewater treatment plants (WWTPs) (Roesch et al. 2022). Since sewage sludge is often used as fertilizer, its application on agricultural soils has been observed as a significant entry path for PFAS into the environment, specifically in our food chain. In Germany the sewage sludge/biosolid application on agricultural land was banned with the amendment of the German Sewage Sludge Ordinance and by 2029 sewage sludge application will be totally prohibited. However, phosphorus (P) from sewage sludge should still be recycled in WWTPs of cities with a population larger than 50,000 residents. To produce high-quality P-fertilizers for a circular economy, PFAS and other pollutants (e.g. pesticides and pharmaceuticals) must be separated from sewage sludge. Due to the strong diversity of industrial PFAS usage it is not clear if a safe application of novel recycled P-fertilizers from WWTPs can be guaranteed. Therefore, we analyzed various sewage sludges and wastewater-based fertilizers. Sewage sludge (SL) samples from various WWTPs in Germany and Switzerland, six sewage sludge ashes (SSA) from Germany, six thermally treated SL and SSA samples with different additives (temperatures: 700-1050 °C), two pyrolyzed SL samples (temperature: 400 °C) and two struvite samples from Germany and Canada were analyzed. The goal was to quantify PFAS in sewage sludges and wastewater-based P-fertilizers with the sum parameter extractable organic fluorine (EOF) by combustion ion chromatography (CIC). The results were compared with data from classical LC-MS/MS target analysis as well as selected samples by HR-MS suspect screening. The EOF values of the SLs mainly range between 154 and 538 µg/kg except for one SL which showed an elevated EOF value of 7209 µg/kg due to high organofluorine contamination. For the SSA samples the EOF values were lower and values between LOQ (approx. 60 µg/kg) and 121 µg/kg could be detected. For the pyrolyzed SLs no EOF values above the LOQ were detected. Moreover, the two wastewater-based struvite fertilizers contain 96 and 112 µg/kg EOF, respectively. In contrast to the EOF values, the sum of PFAS target values were relatively low for all SLs. Additional applied PFAS HR-MS suspect screening aimed to tentatively identify PFAS that could contribute to the hitherto unknown part of the EOF value. The majority of the detected fluorinated compounds are legacy PFAS such as short- and long-chain perfluorocarboxylic acids (PFCA), perfluorosulfonic acids (PFSA), polyfluoroalkyl phosphate esters (PAPs) and perfluorophosphonic acids (PFPA). Moreover, fluorinated pesticides, pharmaceutical as well as aromatic compounds were also identified, which are all included in the EOF parameter. Our research revealed that the current PFAS limit of 100 µg/kg for the sum of PFOS + PFOA in the German Fertilizer Ordinance is no longer up to date. Since the number of known PFAS already exceeds 10,000, the ordinance limit should be updated accordingly. Recent regulations and restrictions on using long-chain PFAS (≥C8) have resulted in a significant shift in the industry towards (ultra-)short-chain alternatives, and other, partly unknown, emerging PFAS. Ultimately, also fluorinated pesticides and pharmaceuticals, which end up as ultrashort PFAS in the WWTPs, have to be considered as possible pollutants in fertilizers from wastewater, too.
Per- and polyfluoroalkyl substances (PFAS) are a group of anionic, cationic and zwitterionic synthetic products, in which the hydrogen atoms on the carbon skeleton of at least one carbon atom have been completely replaced by fluorine atoms and which include more than 4730 compounds, depending on the definition. As a result of continuous and prolific use, mainly in aviation firefighting foams, thousands of industrial and military installations have been found to contain contaminated soil, groundwater and surface water. As a result of the perpetual use of PFAS containing products, effluents and sewage sludge from wastewater treatment plants (WWTPs) have been observed to be an important pathway for PFAS into the environment. In Germany, phosphorus and other nutrients from sewage sludge and wastewater should be recycled in WWTPs of cities with a large population. However, it is not clear if PFAS contamination from wastewater and sewage sludge end up in novel wastewater-based fertilizers. Normally, PFAS are analyzed using PFAS protocols typically with liquid chromatography tandem mass spectrometry (LC-MS/MS) quantification. To get a better overview of the amount of “total PFAS,” we applied sum parameter methods based on combustion ion chromatography (CIC) to screen the PFAS contaminations in various sewage sludge and wastewater-based fertilizers. Furthermore, current decontamination strategies of PFAS-burdened soils mainly consist of adsorption methods using adsorbents for fixation of PFAS in the ground. A second option is the utilization of a “pump and treat” process, cycling polluted soils through a washing plant leading to the concentration of the pollutants in the fine fraction. Only a subsequent, high-energy consuming pyrolysis process guarantees the total destruction of all fluorinated organic contaminants. Both approaches are cost-intensive and not intended for the direct decomposition of all PFAS contaminants. Hence, there is a great demand for innovative developments and chemical treatment technologies, dealing with new strategies of tackling the PFAS problem.
Simple particulate matter sensors are gaining popularity due to their low price, easy handling and good temporal resolution. In this presentation, we report on the performance of a Sharp optical PM sensor GP2Y1010AU0F, which costs less than 15 €.
The sensor is built around an infrared emitting diode (ILED) and a phototransistor detecting the light scattered from the aerosol particle. An electronic circuit shapes the detected light in a pulsed signal. The manufacturer advises sampling the output signal 280 microseconds after the ILED pulse. The measured output voltage is an indicator of dust concentration.
We have built two identical simple PM monitoring devices using Raspberry Pi 3 computer interfacing the PM sensor with Microchip’s MCP3002 ADC via SPI. The ADC is capable of more than 100 ksamples/s at 10-bit resolution. The Rpi3 was pulsing the sensor at 10Hz, digitizing and saving the data and sending the results wirelessly.
Sensor’s output pulse shape was sampled with 10 microsecond time steps and saved, thus making offline analysis possible. A time jitter of output pulses can be observed and suggests a peak fitting as a better approach to the signal readout compared to the single sampling at a fixed time after pulse triggering We compared both methods.
A pot experiment was carried out with maize to determine the phosphorus (P) plant-availability of different secondary P-fertilizers derived from wastewater. We analyzed the respective soils by P K-edge X-ray absorption near-edge structure (XANES) spectroscopy to determine the P chemical forms that were present and determine the transformation processes. Macro- and micro-XANES spectroscopy were used to determine the chemical state of the overall soil P and identify P compounds in P-rich spots. Mainly organic P and/or P adsorbed on organic matter or other substrates were detected in unfertilized and fertilized soils. In addition, there were indications for the formation of ammonium phosphates in some fertilized soils. However, this effect was not seen in the maize yield of all P-fertilizers. The observed reactions between phosphate from secondary P-fertilizers and cofertilized nitrogen compounds should be further investigated. Formation of highly plant-available compounds such as ammonium phosphates could make secondary P-fertilizers more competitive to commercial phosphate rock-based fertilizers with positive effects on resources conservation.