Ingenieurwissenschaften und zugeordnete Tätigkeiten
Filtern
Erscheinungsjahr
Dokumenttyp
- Posterpräsentation (797) (entfernen)
Sprache
- Englisch (663)
- Deutsch (133)
- Französisch (1)
Schlagworte
- Corrosion (36)
- Additive manufacturing (30)
- Mechanochemistry (24)
- Additive Manufacturing (20)
- Glass (20)
- Nanoparticles (19)
- Crystallization (17)
- Degradation (14)
- Fluorescence (14)
- In situ (14)
- Computed tomography (13)
- Residual stress (13)
- Korrosion (12)
- Biofilm (11)
- Hydrogen (11)
- Laser-induced periodic surface structures (LIPSS) (11)
- Microstructure (11)
- SAXS (11)
- Catalysis (10)
- Methanogens (10)
- Nanoparticle (10)
- Sintering (10)
- Thermography (10)
- X-ray refraction (10)
- Boehmite (9)
- Computed Tomography (9)
- Stainless steel (9)
- AFM (8)
- Cocrystal (8)
- KorroPad (8)
- Laser powder bed fusion (8)
- Quality assurance (8)
- Corrosion resistance (7)
- EPR (7)
- Electron microscopy (7)
- Heat treatment (7)
- Nichtrostender Stahl (7)
- PE-HD (7)
- Selective laser melting (7)
- Synthesis (7)
- 316L (6)
- Amorphous phases (6)
- Automation (6)
- Creep (6)
- DNA (6)
- Dosimetry (6)
- Femtosecond laser ablation (6)
- Geant4 (6)
- Heterogeneous catalysis (6)
- MIC (6)
- MOFs (6)
- Microdosimetry (6)
- Neutron diffraction (6)
- Oxidation (6)
- Phosphates (6)
- Polymer (6)
- Polymorphism (6)
- Prüfmethode (6)
- Qualitätssicherung (6)
- Simulation (6)
- ToF-SIMS (6)
- Welding (6)
- Additive Fertigung (5)
- Aluminium (5)
- Archaea (5)
- C-F bond activation (5)
- Coarsening (5)
- DFT (5)
- Dielectric spectroscopy (5)
- Duplexstahl (5)
- Dye (5)
- FTIR (5)
- Gefahrgut (5)
- Gefahrstoff (5)
- LEE (5)
- Laser Powder Bed Fusion (5)
- Microplastic (5)
- Microplastics (5)
- Milling (5)
- Nanocomposite (5)
- Nanocomposites (5)
- Niobium carbide (NbC) (5)
- PBF-LB/M (5)
- Polymorph (5)
- Quantum dot (5)
- Radiation damage (5)
- Reference material (5)
- SEM (5)
- Self-healing (5)
- Silver nanoparticles (5)
- Struvite (5)
- ThermoCalc (5)
- Thin films (5)
- Transition metal (5)
- Transmission electron microscopy (5)
- UHPC (5)
- Wear (5)
- XANES (5)
- Ageing (4)
- AlSi10Mg (4)
- AuNP (4)
- Bioactive (4)
- Composite-Druckgefäße (4)
- Concrete (4)
- Corrosion testing (4)
- Crack growth (4)
- DCB (4)
- DNA damage (4)
- Diesel (4)
- Digitalisierung (4)
- Discotic Liquid Crystals (4)
- Energy deposit (4)
- FAIR (4)
- Fatigue (4)
- Flexible crystals (4)
- Friction (4)
- Geant4-DNA (4)
- Graphene (4)
- Hardness (4)
- Hydrogen assisted cracking (4)
- Imaging (4)
- Implants (4)
- Inconel 686 (4)
- Iron oxide nanoparticles (4)
- LIBS (4)
- Laser Beam Melting (4)
- Laser profilometry (4)
- Low energy electrons (4)
- MCS (4)
- Metal phosphonates (4)
- Monte-Carlo simulation (4)
- NMR (4)
- Nano (4)
- Nanoconfinement (4)
- Nanoplastic (4)
- Pitting corrosion (4)
- Polyethylene (4)
- Polymers (4)
- Radiationtherapy (4)
- Radioactive decay (4)
- Ringversuch (4)
- Spectroscopic ellipsometry (4)
- Steel (4)
- Sulfidation (4)
- Synchrotron (4)
- TEM (4)
- TiO2 (4)
- Tribology (4)
- Upconversion (4)
- Validierung (4)
- X-ray diffraction (4)
- XPS (4)
- XRD (4)
- 3D High-temperature shape screening (3)
- AM (3)
- Ab-initio (3)
- Alloy 2618A (3)
- Assay (3)
- Bending modulus (3)
- Beta decay (3)
- Biodiesel (3)
- Bitumen (3)
- Bonding analysis (3)
- Brachytherapy (3)
- Cancer treatment (3)
- Carbon nanotubes (3)
- Cermets (3)
- Clustered nanoparticles (3)
- Coating (3)
- Computational Chemistry (3)
- Conductivity (3)
- Corundum grinding (3)
- Dangerous goods (3)
- Database (3)
- Diffusion coefficient (3)
- EBSD (3)
- Ellipsometry (3)
- Environmental Simulation (3)
- Epoxy (3)
- FIB (3)
- Flourescence (3)
- Flow cytometry (3)
- Glass ceramic (3)
- Glass composition (3)
- Gold Nanoparticles (3)
- In situ monitoring (3)
- Korrosionsbeständigkeit (3)
- Korundschleifen (3)
- LCF (3)
- Laser cladding (3)
- Laser implantation (3)
- Livermore model (3)
- Luminescence (3)
- MIPs (3)
- Machine Learning (3)
- Machine learning (3)
- Martensitic stainless steels (3)
- Materials Informatics (3)
- Mesoporosity (3)
- Metallographie (3)
- Metrology (3)
- Microbial induced corrosion (3)
- Microbiologically influenced corrosion (3)
- Micropatterning (3)
- Microscopy (3)
- Molecularly imprinted polymers (3)
- Monitoring (3)
- NDT (3)
- NP (3)
- NTE (3)
- Nanofibers (3)
- Nanomaterial (3)
- Nichtrostende Stähle (3)
- OECD (3)
- OER (3)
- OH radical (3)
- Oberflächenbearbeitung (3)
- Optical spectroscopy (3)
- Orientation (3)
- Oxygen Reduction Reaction (3)
- PGM-free catalyst (3)
- PXRD (3)
- Penelope model (3)
- Phase grating (3)
- Polydopamine (3)
- Polymer 3R (3)
- Polymer blends (3)
- Polypropylene (3)
- ProMoAM (3)
- Quantum dots (3)
- REACH (3)
- Radiation therapy (3)
- Radiolysis (3)
- Raman Spectroscopy (3)
- Reactive extrusion (3)
- Reference data (3)
- Residual Stress (3)
- Rigidity (3)
- Röntgenrefraktion (3)
- SLM (3)
- Sample preparation (3)
- Schadensanalyse (3)
- Schweißen (3)
- Sensibilisierung (3)
- Sialic acid (3)
- Soda-lime silicate glass (3)
- Sol-gel (3)
- Solid-state (3)
- Specific heat spectroscopy (3)
- Strahlen (3)
- Surface analysis (3)
- Surface chemistry (3)
- Synchrotron tomography (3)
- TDEP (3)
- TOPAS (3)
- TOPAS-nbio (3)
- Thermoelectrics (3)
- Thin Films (3)
- Thin polymeric films (3)
- Ti-6Al-4V (3)
- Two-photon polymerisation (3)
- VSSA (3)
- Vickers (3)
- WAXS (3)
- Waveguide (3)
- Wärmebehandlung (3)
- X-ray fluorescence (3)
- ZCF (3)
- ZrF4 (3)
- particle scattering (3)
- 3D (2)
- AGIL (2)
- AIS (2)
- ATR (2)
- Absorption edge tomography (2)
- Adaptives Schweißen (2)
- Adsorbed Layer (2)
- Aktivkohle (2)
- Alkali-silica-reaction (2)
- Alterung von Pyrotechnik (2)
- Aluminium alloys (2)
- Aluminum (2)
- Antimicrobials (2)
- Atomic packing factor (2)
- Atomization (2)
- Austenitic stainless steel (2)
- BAMline (2)
- Bacteria (2)
- Bacterial adhesion (2)
- Barcoding (2)
- Bead (2)
- Bildanalyse (2)
- Bildgebung (2)
- Broadband dielectric spectroscopy (2)
- Building Materials (2)
- Building materials (2)
- CALPHAD (2)
- CCMat (2)
- CCS (2)
- CLP (2)
- Calcium cobaltite (2)
- Carbon capture (2)
- Carbon dioxide (2)
- Catalysts (2)
- Characterization (2)
- Chemical composition (2)
- Chemically Complex Materials (2)
- Composite (2)
- Composites (2)
- Computertomographie (2)
- Confocal (2)
- Core-shell (2)
- Corrosion Testing (2)
- Corrosion inhibition (2)
- Crack (2)
- Crack Propagation (2)
- Crack growth velocity (2)
- Crack healing (2)
- Crack intensity factor (2)
- Creep-resistant steel (2)
- Crystal orientation (2)
- Cycloalyphatic epoxy oligosiloxane (2)
- Damage (2)
- Dark-field transmission electron microscopy (DFTEM) (2)
- Data fusion (2)
- Dental materials (2)
- Deuterium (2)
- Digitalization (2)
- Double cantilever beam (2)
- Durability (2)
- ECHA (2)
- EDX (2)
- ESEM (2)
- Eigenspannungen (2)
- Einstufung (2)
- Electrocatalysis (2)
- Electrochemistry (2)
- Electron beam induced modification (2)
- Elemental composition (2)
- Emission (2)
- Emission test chamber (2)
- Encoding (2)
- Environmental stress cracking (2)
- Environmental stress cracking (ESC) (2)
- Exchange interaction (2)
- Explosionsschutz (2)
- Explosivstoffe (2)
- FEM (2)
- Faseroptik (2)
- FeNi-Oxide NPs (2)
- Ferromagnetism (2)
- Finite element method (2)
- Fire (2)
- Friction and wear (2)
- Fused Filament Fabrication (2)
- GD-OES (2)
- GMR (2)
- GMR-Sensorik (2)
- Gas-Staub-Gemische (2)
- Gel-type electrolytes (2)
- Geothermal (2)
- Glas (2)
- Gold nanocluster (2)
- Gold nanoparticles (2)
- Green chemistry (2)
- Grüneisen parameter (2)
- Hazardous substances (2)
- Henry's constant (2)
- High Pressure (2)
- High temperature corrosion (2)
- High-temperature corrosion (2)
- Hot stamping (2)
- Hybride Gemische (2)
- Hydrogen permeability (2)
- Hydrogen storage (2)
- IUCLID (2)
- Image analysis (2)
- Image processing (2)
- Imaging techniques (2)
- In situ heating (2)
- In-situ (2)
- InP (2)
- Inks (2)
- Integrating sphere spectroscopy (2)
- Interatomic potentials (2)
- Ionic Liquid crystals (2)
- Iron (2)
- L-PBF (2)
- LLG (2)
- LMD (2)
- LTCC (2)
- Landau Lifshitz equation (2)
- Laser beam melting (2)
- Laser beam welding (2)
- Laser metal deposition (2)
- Least-squares adjustment (2)
- Lichtbogensensorik (2)
- Lifetime (2)
- Lithium Ion Batteries (2)
- Load transfer (2)
- Low Cycle Fatigue (2)
- MMC (2)
- MOF (2)
- MSG-Engspaltschweißen (2)
- Macrophages (2)
- Magnesium alloy (2)
- Magnetic moment (2)
- Magnetic nanoparticles (2)
- Materialcharakterisierung (2)
- Metadata schema (2)
- Metal Matrix Composite (2)
- Metal matrix composite (2)
- Metal organic frameworks (2)
- Metals (2)
- Method (2)
- Micromagnetism (2)
- Microwave synthesis (2)
- Mikrobiell induzierte Korrosion (2)
- Modellierung (2)
- Multielectrode array sensors (2)
- Multiplexing (2)
- NFDI (2)
- NIR (2)
- Nanomechanics (2)
- Nanosensor (2)
- Neutron (2)
- Neutron Diffraction (2)
- Non-classical crystallization (2)
- Normung (2)
- Numerical modeling (2)
- OOMMF (2)
- Oberflächenenergie (2)
- Object oriented micromagnetic framework (2)
- Online Process Monitoring (2)
- Ontologie (2)
- Ontology (2)
- Optics (2)
- Oxidglas (2)
- Particle (2)
- Phonons (2)
- Photocatalysis (2)
- Plastic (2)
- Plattform MaterialDigital (2)
- Polycarbonate (2)
- Polymer bilayer coatings (2)
- Porosity (2)
- Powder Bed Fusion (2)
- Precipitation (2)
- Process Monitoring (2)
- Protein (2)
- Proteins (2)
- Prozessüberwachung (2)
- Pyrotechnik (2)
- QHA (2)
- QY (2)
- Quantum yield (2)
- Quecksilberporosimetrie (2)
- REM (2)
- Radiotherapy (2)
- Referenzdaten (2)
- Reflectography (2)
- Resistance (2)
- Resonance frequency (2)
- Robotische Glasschmelzanlage (2)
- Roughness (2)
- SCNC (2)
- SEM/EDS (2)
- SIMS (2)
- SWIR (2)
- Scanning electrochemical microscope (SECM) (2)
- Selected Laser Melting (2)
- Semantic Interoperability (2)
- Semantic Web Technologies (2)
- Semiconductor (2)
- Sicherheitstechnische Kenngrößen (2)
- Silica (2)
- Single molecule (2)
- Single particle spectroscopy (2)
- Small-angle scattering (2)
- SnO2 (2)
- Stainless steels (2)
- Stickstoff (2)
- Stochastic Landau Lifshitz Gilbert equation (2)
- Structural Health Monitoring (2)
- Surface (2)
- Surface functionalization (2)
- Surface integrity (2)
- Surface modification (2)
- Synchrotron X-Ray Refraction (2)
- Synchrotron X-ray computed tomography (2)
- Syngle Crystal alloy (2)
- TED-GC/MS (2)
- Temperature (2)
- Thermally induced porosity (2)
- Thermodynamik (2)
- Thermoelectric materials (2)
- Thermografie (2)
- Thermogravimetrie (2)
- Thin film metrology (2)
- Titanium (2)
- Tool wear (2)
- Topotactic transformation (2)
- Traceability (2)
- Transition metals (2)
- Tungsten carbide (WC) (2)
- Ultra-Thin films (2)
- Ultrashort laser processing (2)
- Ultrasonic-assisted milling (2)
- Ultrasound (2)
- VOC (2)
- Verbundfestigkeit (2)
- Vessels (2)
- Wasserstoff (2)
- Water content (2)
- Water speciation (2)
- Wetting (2)
- Wood (2)
- X-ray computed tomography (2)
- XRF (2)
- Zeolitic imidazolate framework (2)
- ZfP (2)
- Zinc coatings (2)
- Zustandsüberwachung (2)
- beta particle (2)
- cylinders (2)
- 18HLT01 MetVes II (1)
- 29Si-27Al TRAPDOR MAS (1)
- 316L Stainless Steel (1)
- 3D High-temperatue shape screening (1)
- 3D analysis (1)
- 3D coherence scanning interferometry (CSI) (1)
- 3D imaging (1)
- 3D printing (1)
- 3D tomography (1)
- 3D-Formerkennung (1)
- 5-hydroxynicotinic acid (1)
- 5G (1)
- AFM-IR (1)
- AISI 304L (1)
- ALD (atomic layer deposited) (1)
- ALD-Beschichtung (1)
- ALD-Hybridprozesse (1)
- AM IN718 (1)
- ASAXS (1)
- ASR (1)
- ATH (1)
- ATRP (1)
- Abkühlgeschwindigkeit (1)
- Absolute flourometry (1)
- Absorption edge (1)
- Acoustic Emission (1)
- Acoustic Emission (AE) (1)
- Acrylamide based polymers (1)
- Active pharmaceutical ingredient (API) (1)
- Additiv gefertigter Stahl (1)
- Additive Manufacture (1)
- Additive Fertigung (AM) (1)
- Additive surface treatment (1)
- Admixtures (1)
- Adsorbed layer (1)
- Advanced manufacturing (1)
- Advanced materials (1)
- Advanced nanomaterials (1)
- Aerial Robot (1)
- Aerosole (1)
- Affinity chromatography (1)
- Affinity extraction (1)
- Affinity support (1)
- Ag2S (1)
- Aggressive environement (1)
- Aggressive environment (1)
- Aging (1)
- Aging mechanisms (1)
- Air Void System (1)
- Air exchange rate (1)
- Al alloy (1)
- Al-Cu-Li alloys (1)
- Al2O3 (1)
- Al2O3 thin films (1)
- Al2O3-Schichten (1)
- AlSi10Mg alloy (1)
- Albumin (1)
- Alcali activated binders (1)
- Alkali-Kieselsäure-Reaktion (1)
- Alkalialumosilicatsysteme (1)
- Alkaline earth metal (1)
- Aln (1)
- Altglasfragmente (1)
- Altpapierrecycling (1)
- Alumina (1)
- Aluminium Alloy (1)
- Aluminum oxide (1)
- Amino acid analysis (1)
- Ammoniumnitrat (1)
- Amorphous silica particles (1)
- Amphiphilicity (1)
- Amplification (1)
- Anaerob (1)
- Analyser-based imaging (1)
- Analytical solution (1)
- Anisotropy (1)
- Anlage (1)
- Annealing study (1)
- Anodic Aluminum Oxide (1)
- Anodization (1)
- Antibiotics (1)
- Antibodies (1)
- Antibody purification (1)
- Aromatic amino acid analysis AAAA (1)
- Artefact (1)
- Artificial digestion (1)
- Asphaltene content (1)
- Assays (1)
- Atmospheric Corrosion (1)
- Atmospheric Plasma Spraying (1)
- Atomic Force Microscopy (1)
- Atomic Layer Deposition (1)
- Atomic force microscopy (1)
- Atomic fraction (1)
- Ausbildung (1)
- Austenitic stainless steels (1)
- Austenitic steel (1)
- Automatisation (1)
- Automatisierung (1)
- BADGER film (1)
- BBR (1)
- BCS (1)
- BLE (1)
- BODIPY (1)
- BSA (1)
- BTS (1)
- Bacterial growth (1)
- BadgerFilm (1)
- Baudenkmal (1)
- Baustahl (1)
- Baustoffe (1)
- Bauzustandsanalyse (1)
- Benannte Stelle (1)
- Bench braking sequence (1)
- Beratung Behörden/Ministerien (1)
- Beschichtung (1)
- Beta particle (1)
- Beton (1)
- Betonautobahn (1)
- Betonautobahnen (1)
- Betonschallplatte (1)
- Betonschäden (1)
- Bewitterung (1)
- Bexarotene (1)
- Bildverarbeitung (1)
- Bio Ceramics (1)
- Bio-SAXS (1)
- Bio-receptive (1)
- BioSAXS (1)
- Bioactive glass (1)
- Biocide (1)
- Biocides (1)
- Biocomposite (1)
- Biocorrosion (1)
- Biofilm cultivation (1)
- Biofilm formation (1)
- Biofilm growth (1)
- Biofilms (1)
- Bioimaging (1)
- Biomasseverbrennung (1)
- Biomimetics (1)
- Bioreceptivity (1)
- Bioresorbable (1)
- Blast injury (1)
- Bluetooth Low Energy (1)
- Boehmite alumina (1)
- Bonding Analysis (1)
- Bovine serum albumin (1)
- Bragg-edge (1)
- Brazing (1)
- Bremsbeläge (1)
- Brittle / ductile fracture behavior (1)
- Brittle fracture (1)
- Bronze (1)
- Brown-rot fungi (1)
- Bruchmechanik (1)
- Build Angle (1)
- Building products (1)
- Bulk diffusion (1)
- Bulk material (1)
- Bulk properties ageing (1)
- Burst pressure (1)
- Burst test (1)
- C-C coupling (1)
- CALPHAD databases analysis (1)
- CCUS (1)
- CEO (1)
- CERN (1)
- CFD (1)
- CMAS (1)
- CMAS - Calcium-Magnesium-Aluminiumsilikat (1)
- CMSX4 (1)
- CO2-Korrosion (1)
- CONSENS (1)
- CUSP (1)
- Calcium sulfoaluminate cement (1)
- Calculation (1)
- Camera (1)
- Capsules (1)
- Carbide (1)
- Carbon (1)
- Carbon Fiber Reinforced Plastics (1)
- Carbon dot (1)
- Carbon fibers (1)
- Carbon nanomembranes (1)
- Carrier Gas Hot Extraction (1)
- Carrier gas hot extraction (1)
- CdSe (1)
- Cearmics (1)
- Cell imaging (1)
- Cement (1)
- Cement hydration (1)
- Ceramic (1)
- Ceramic spring (1)
- Ceramic-ceramc joints (1)
- Ceramics (1)
- Cermet (1)
- Certification (1)
- Certified reference material (1)
- Certified standards (1)
- Charakterisierung (1)
- Chemical Bonds (1)
- Chemical analyses (1)
- Chemical compositions (1)
- Chemically Complex Alloy (1)
- Cheminformatics (1)
- Chloride (1)
- Chromatography (HIC) (1)
- Chromium (1)
- Chromium (III) complexes (1)
- Chromium oxide (1)
- Chromstahl (1)
- Climate chamber simulation (1)
- Co-axial monitoring (1)
- CoCrMo (1)
- Coatings (1)
- Coda Wave Interferometry (1)
- Coherent Rayleigh OTDR (1)
- Cold Spray (1)
- Column chromatography (1)
- Columnar crystal growth (1)
- Columnar liquid crystals (1)
- Compatible solute (1)
- Complex concentrated alloy (CCA) (1)
- Component test (1)
- Composite cylinder (1)
- Composition (1)
- Compound (1)
- Compression (1)
- Compsite tapes (1)
- Configurational entropy (1)
- Confined Columnar Liquid Crystals (1)
- Confocal fluorescence microscopy (1)
- Conservation (1)
- Construction products (1)
- Consumer articles (1)
- Contact resonance (1)
- Conventional testing (1)
- Convolutional neural networks (1)
- Coordination polymer (1)
- Core-shell architecture (1)
- Core/shell materials (1)
- Corosion (1)
- Corrosion behaviour (1)
- Corrosion investigations (1)
- Corrosion loss (1)
- Corrosion product layer (1)
- Corrosion products (1)
- Corrosion protecting system (1)
- Cosolute (1)
- Crack evolution (1)
- Crack propagation (1)
- Crack propagation analysis (1)
- Cracks (1)
- Creep-resistant Steel (1)
- Crush (1)
- Cryo-TEM (1)
- Crystal Engineering (1)
- Crystal plasticity (1)
- Crystal structure (1)
- Crystalline structure (1)
- Curing Monitoring (1)
- Curvelet Transform (1)
- Cutting material (1)
- Cutting tool (1)
- Cutting tools (1)
- Cyclic R-curve (1)
- DED-L (1)
- DIC assisted compression (1)
- DIN 52186 (1)
- DIN EN 252 (1)
- DIN EN ISO/IEC 17025:2018 (1)
- DRIFTS (1)
- DSR (1)
- Damage Analysis (1)
- Damage mechanism (1)
- Damage repair (1)
- Dangerous goods packaging (1)
- Dangerous goods packagings (1)
- Dark-field transmission electron microscopy (1)
- Data (1)
- Data Fusion (1)
- Data Integration (1)
- Data Interoperability (1)
- Data Science (1)
- Data analysis (1)
- Databases (1)
- Datenanalyse (1)
- Datenträger (1)
- Deep Learning (1)
- Defect detection (1)
- Defects (1)
- Deformation (1)
- Deformation-Induced Martensite (1)
- Deformationen (1)
- Degradation of Mechanical Properties (1)
- Degree of damage (1)
- Degree of purity (1)
- Delamination (1)
- Demonstrators (1)
- Dendrimersomes (1)
- Dendritic amphiphiles (1)
- Density (1)
- Density Functional Theory (1)
- Dental material (1)
- Depth-profiling (1)
- Design Fire (1)
- Destabilization (1)
- Detection (1)
- Dielectric Spectroscopy (1)
- Diffraction (1)
- Diffraction Enhanced Imaging (1)
- Diffusion (1)
- Diffusion Coefficient (1)
- Diffusion barrier (1)
- Digital material representation (1)
- Digital twin (1)
- Digitaler Zwilling (1)
- Digtial Representation (1)
- Diopside (1)
- Direct fluorine-metal bond (1)
- Direct laser writing (1)
- Discotic Liquid Crystal (1)
- Discotic liquid crystals (1)
- Dislocations (1)
- Distortion (1)
- Distributed acoustic sensing (1)
- Distributed fiber optic sensors (1)
- Distributed vibration sensing (1)
- Distribution during filling (1)
- Disäuren (1)
- Doping study (1)
- Downstream processing (1)
- Dredging mud (1)
- Drop test (1)
- Druckwelle (1)
- Duplex stainless steel (1)
- Duplex stainless steels (1)
- Dust analysis (1)
- Dynamic light scattering (1)
- Dynamics (1)
- EBSD analysis (1)
- EC4SafeNano (1)
- EDS (1)
- EDX Analysis (1)
- EDXRD (1)
- EMN (1)
- EMPIR project (1)
- EPMA (1)
- ESI-TOF-MS (1)
- EU H2020 project (1)
- Ectoin (1)
- Ectoine (1)
- Eddy Current (1)
- Edelstahl (1)
- Eigenspannung (1)
- Eindringmodul (1)
- Einkristalllegierung (1)
- Einzelfaserdurchzugsversuch (1)
- Eisen (1)
- Elastomer (1)
- Elastomers (1)
- Electro catalyst (1)
- Electrochemical noise (1)
- Electrodeposited Ni - coatings (1)
- Electrolysis (1)
- Electromicroscopy (1)
- Electron Backscatter Diffraction (1)
- Electron Microscopy (1)
- Electron Probe Microanalysis (EPMA) (1)
- Electron beam (1)
- Electron probe microanallysis (EPMA) (1)
- Electron probe microanalysis (EPMA) (1)
- Electronic Lab Notebook (1)
- Electrospinning (1)
- Elektrochemische Charakterisierung (1)
- Elevated Temperatures (1)
- Elevated temperatures (1)
- Ellipsometric metrology (1)
- Emission chamber testing (1)
- Emissivity (1)
- Energetic materials (1)
- Energietechnik (1)
- Energy (1)
- Energy dispersive X-ray spectroscopy (1)
- Energy input (1)
- Engineered Nanomaterials (1)
- Environment (1)
- Epox (1)
- Epoxy nanocomposite (1)
- Er(III) (1)
- Erneuerbare Energien (1)
- Erosion (1)
- European Metrology Network (1)
- European standard (1)
- Exciton diffusion (1)
- Experimental study (1)
- Extracellular polymeric substances (1)
- Extracellular vesicles (EV) (1)
- Extrusion (1)
- FE (1)
- FIB/SEM (1)
- FNCT (1)
- FTIR spectroscopy (1)
- Fachwerkträger (1)
- Fallhammer (1)
- Far-infrared spectroscopy (1)
- Farbätzen (1)
- Fasermodifikation (1)
- Fatigue Crack Growth (1)
- Fatigue crack growth (1)
- Fatigue damage (1)
- Façade (1)
- Fe-Cr alloys (1)
- Fe-Ni (1)
- Fe2TiO5 (1)
- FeCr- alloys (1)
- FeNi (1)
- FeNi thin film (1)
- FeSnOx (1)
- Femtosecond laser (1)
- Femtosecond laser processing (1)
- Ferroelektret (1)
- Fiber (1)
- Fiber reinforced dental post (1)
- Fiber sensors (1)
- Fiber-optic microarray (1)
- Fiberglass composite (1)
- Film depositition (1)
- Film thickness determination (1)
- Finite Element Method (1)
- Finite Element Modelling (1)
- Fire Retardant (1)
- Flow Cell (1)
- Flow-System (1)
- Fluorescence quenching (1)
- Fluorescence spectroscopy (1)
- Fluorescent dyes (1)
- Fluorescent polymer optical fibres (1)
- Fluoride (1)
- Fluorides (1)
- Fluorine Interaction (1)
- Flüssigmetallversprödung (1)
- Foam tiles (1)
- Focussed ion beam (1)
- Focussed ion beam growth (1)
- Force distance curves (1)
- Formaldehyde (1)
- Foundation (1)
- Fractional factorial (1)
- Fractography (1)
- Fracture Toughness (1)
- Fracture surface analysis (1)
- Fragmentation (1)
- Fraktografie (1)
- Fraktographie (1)
- Fre (1)
- Fresnoit (1)
- Full Notch Creep Test (1)
- Full Notch Creep Test (FNCT) (1)
- Full-Notch Creep Test (FNCT) (1)
- Fullerene (1)
- Functional group detection (1)
- Functionality type distribution (1)
- Funktionelle Beschichtungen (1)
- Funtional Groups (1)
- Füllgradregelung (1)
- G5P (1)
- GEXRF (1)
- GUM-compliance (1)
- GVP (1)
- Gamma-Co60 radiation (1)
- Gamma-irradiation (1)
- Gas Sorption (1)
- Gas Tomography (1)
- Gas solubility (1)
- Gas turbine (1)
- Gefüge (1)
- Gel electrolytes (1)
- Gelartige Elektrolyte (1)
- Gene five protein (1)
- Generator (1)
- Geopolymer (1)
- Geopolymers (1)
- Geothermal energy (1)
- Geothermie (1)
- Ggraphene polymer nanocomposite (1)
- GlasDigital (1)
- Glasanalyse (1)
- Glasig-kristalline Sinterwerkstoffe (1)
- Glaskeramik (1)
- Glass paints (1)
- Glass transformation temperature (1)
- Glass transition (1)
- Glass-ceramic (1)
- Glasstruktur (1)
- Gleeble (1)
- Gleitlinien (1)
- Glue (1)
- Glutaraldehyde (1)
- Glycerin (1)
- Gold (1)
- Gold Nanoparticle (1)
- Gold mosaics (1)
- Grain boundary corrosion (1)
- Graphene /-oxide (1)
- Graphene functionalisation (1)
- Graphene functionalization (1)
- Graphene polymer nanocomposite (1)
- Grazing exit (1)
- Grenzflächenaktive Verbindung (1)
- Grey cast iron machining (1)
- Growth Kinetics (1)
- Guanidine receptor (1)
- Guideline (1)
- HDPE Sorption (1)
- HF (1)
- HR-CS-AAS (1)
- HV cable accessories (1)
- HV-Insulation (1)
- Haftfestigkeit (1)
- Haftvermittler (1)
- Halbleiterphysik (1)
- Hard X-ray photoelectron spectroscopy (HAXPES) (1)
- Harmonisation in microplastics (1)
- Harsh environments (1)
- Hatch length (1)
- Hauptkomponentenanalyse (1)
- Hazmat (1)
- Heat Treatment (1)
- Heating oil storage tanks (1)
- Heating oil tanks (1)
- Heißzug (1)
- Helium- und Wasserstoffpermeation (1)
- Heterogene plastische Deformation (1)
- Hexafluorobenzen (1)
- HfO2 (1)
- High Cycle Fatigue (1)
- High Molecular Polyethylene (1)
- High Temperature Testing (1)
- High Voltage Insulation (1)
- High entropy alloy (1)
- High entropy alloys (1)
- High resolution ultrasonic testing (1)
- High temperature (1)
- High temperature corrosion resistance (1)
- High voltage cable accessories (1)
- High-Performance Concrete (1)
- High-density polyethylene (1)
- High-entropy alloys (1)
- High-strength steels (1)
- High-temperature stability (1)
- Historic buildings (1)
- Hochfester Feinkornbaustahl (1)
- Hochtemperaturanwendungen (1)
- Hollow specimen (1)
- Holz (1)
- Holzbaustoff (1)
- Holzprüfung (1)
- Homemade explosives (1)
- Honeycomb structure (1)
- Horizontaldilatometer (1)
- Human plasma (1)
- Humidity (1)
- Hybrid inorganic/organic copolymers (1)
- Hydration (1)
- Hydrogen diffusion (1)
- Hydrogen permeation (1)
- Hydrophobic interaction (1)
- Hydrothermal treatment (1)
- Hydroxyectoine (1)
- Härtevergleichsplatten (1)
- Härteverlauf Schweißnaht (1)
- ILC (1)
- IN 625 (1)
- IN 718 (1)
- IN718 (1)
- IR (1)
- IR spectroscopy (1)
- ISO 5725 (1)
- Illumina (1)
- ImAFM (1)
- Image Denoising (1)
- Image segmentation (1)
- Immersion tank testing (1)
- Impact excitation (1)
- Impact strength (1)
- Implant-Test (1)
- In situ Raman (1)
- In situ XRD (1)
- In situ analysis (1)
- In situ diffraction (1)
- In situ measurement (1)
- In situ measurement, (1)
- In situ tensile test (1)
- In situ testing (1)
- In-Situ (1)
- In-Situ Characterization (1)
- In-situ Monitoring (1)
- In-situ SAXS/WAXS (1)
- In-situ compression CT (1)
- In-situ heat treatment (1)
- In-situ loading (1)
- In-situ monitoring (1)
- In-situ tomography (1)
- In718 (1)
- Inconel 718 (1)
- Indoor air (1)
- Industrieabwasseraufbereitung (1)
- Infrared spectroscopy (1)
- Initial attachment (1)
- Initial hydration (1)
- Innovative Messtechnik (1)
- Inorganic polymers (1)
- Instrumented indentation testing (1)
- Instrumentierte Eindringprüfung (1)
- Integrated analysis (1)
- Interface (1)
- Interim storage (1)
- Interlaboratory comparison (1)
- Intermediate (1)
- Internal friction (1)
- Internal oxidation (1)
- Interoperability (1)
- Interpenetrating polymer network (1)
- Interpenetrating polymer networks (1)
- Interphase (1)
- Invasive Arten (1)
- Inverse Analysis (1)
- Inverse analysis (1)
- Inverse problem (1)
- Ionic liquids (1)
- Ionizing radiation damage (1)
- Iridium oxide films (1)
- Iridium-titanium mixed oxides (1)
- Iron aluminides (1)
- Iron oxide (1)
- Isotope analysis (1)
- JNP AdvManuNet (1)
- Kalottenverfahren (1)
- Kaltrissprüfung (1)
- Kavitation (1)
- Keggin Cluster (1)
- Kelvinsondenkraftmikroskopie (1)
- Keramik (1)
- Kiefernholz (1)
- Kieselsäure (1)
- Klebfestigkeit (1)
- Kleidermotte (1)
- Knoevenagel (1)
- Knoevenagel condensation (1)
- Knowledge Readiness Level (1)
- Knowledge Representation (1)
- Knowledge graph and ontologies (1)
- Kombinierete korrosive und mechanische Beanspruchung (1)
- Kondensation (1)
- Konformitätsbewertung (1)
- Konformitötsbewertung (1)
- Kontrastierung (1)
- Korrosionsabtrag (1)
- Kraftabhängige Funktion (1)
- Kristallplastizität (1)
- Künstliche neuronale Netze (1)
- L-PBF 316L (1)
- LBM (1)
- LIBS TIG welding (1)
- LIPSS (1)
- LPBF (1)
- LPSO (1)
- LTCC multilayer (1)
- Laboratory Container (1)
- Laboratory method (1)
- Laborvergleich Härte (1)
- Lanthanide(III) (1)
- Large scale test (1)
- Large-scale production (1)
- Large-scale synthesis (1)
- Large-scale test (1)
- Laser Cladding (1)
- Laser Metal Deposition (1)
- Laser Metal Deposition (LMD) (1)
- Laser ablation (1)
- Laser cludding (1)
- Laser dispersing (1)
- Laser structuring (1)
- Laser-Pulverbettschweißen (1)
- Laser-induced pariodic surface structures (1)
- Laser-induced periodic surface strcutures, LIPSS (1)
- Laserthermografie (1)
- Lasertriangulationssensor (1)
- Latex (1)
- Lattice structure (1)
- Layer-by-layer deposition (1)
- Leaching process (1)
- Least-Squares Adjustment (1)
- Lebensdauer (1)
- Lebensdauerabschätzung (1)
- Lichtmikroskopie (1)
- Ligand (1)
- Ligands (1)
- Lightweight structures (1)
- Lignin (1)
- Lignosulfonate (1)
- Liquid Metal Embrittlement (1)
- Liquid phase sintering (1)
- Lithium batteries (1)
- Lithium-ion batteries (1)
- Lizard (1)
- Load Partition (1)
- Load history (1)
- Loading factor (1)
- Localized corrosion (1)
- Lokale Korrosion (1)
- Long-term monitoring (1)
- Longitudinal Wave (1)
- Low cycle fatigue (1)
- Lubricants (1)
- Luftultraschall (1)
- Luminescence lifetime measurments (1)
- Luminescent materials (1)
- MIC projekt (1)
- MID IR Spectroscopy (1)
- ML (1)
- Machine-Learning Segmentation (1)
- Magic-sized cluster (1)
- Magnesium (1)
- Magnetic nano-particles (1)
- Magnetic stray fields (1)
- Magnetostrictive actuator layer (1)
- Magnetostrictive layer (1)
- Magnetron sputtering (1)
- Manganese oxide (1)
- Maritime atmosphere (1)
- Martensitische nichtrostende Stähle (1)
- Maschinennachgiebigkeit (1)
- Material characterization (1)
- Material degradation (1)
- Material design (1)
- Material model (1)
- Material oxidation (1)
- Material selection (1)
- McSAS3 (1)
- Me-TiO2 (1)
- Measurement uncertainty (1)
- Mechanical Behavior (1)
- Mechanical strength (1)
- Mechanichal behaviour (1)
- Mechanische Kennwertermittlung (1)
- Mechanism (1)
- Mechanochemical oxidation (1)
- Mechanochemical syntheses (1)
- Mechanochemie (1)
- Median lethal energy deposit (1)
- Medieval glasses (1)
- Medieval stained glass (1)
- Mehr-Proben-Kleben (MSB) (1)
- Mehr-Proben-Prüfen (CAT) (1)
- Melt Flow Rate (MFR) (1)
- Melt pool behaviour (1)
- Melting (1)
- Mesoporous (1)
- Mesoporous materials (1)
- Mesoporous thin films (1)
- Messunsicherheit (1)
- Metal matrix composites (1)
- Metal organic framework (1)
- Metal powder characterization (1)
- Metal reducing bacteria (1)
- Metal seal (1)
- Metallsulfide (1)
- Metallurgie (1)
- Methodenvalidierung (1)
- Micro computed tomography (1)
- Micro-XRF (1)
- Micro-heterogeneity (1)
- Microbially influenced corrosion (MIC) (1)
- Microbiological investigation (1)
- Microbiologically Influrenced Corrosion (MIC) (1)
- Microfluidic (1)
- Micromanipulation (1)
- Micromixer (1)
- Microparticles (1)
- Micropatterned dry adhesive (1)
- Microplastics in milk (1)
- Microplastics sampling (1)
- Microprinting (1)
- Microstructure Analysis (1)
- Microstructure analysis (1)
- Microstructure-property relations (1)
- Mikro-CT (1)
- Mikrobiell beeinflusste Korrosion (1)
- Mikrostruktur (1)
- Mineralogie (1)
- Missbräuchliche Verwendung in Stadien (1)
- Mobile anodisation (1)
- Mobile application (1)
- Model alloy (1)
- Model and measurement based analysis (1)
- Modeling (1)
- Moisture (1)
- Moisture drying (1)
- Molar mass distribution (1)
- Molecular Conformation (1)
- Molecular dynamic simulation (1)
- Monte-Carlo simulations (1)
- Morpho-chemical characterization (1)
- Morphology (1)
- Multi-method Metrology (1)
- Multi-sample analysis (1)
- Multielectrode (1)
- Multiphoton Lithography (1)
- Multiphoton lithography (1)
- Multiple ageing and rejuvenation (1)
- Multiplexing sensory fiber-optic microarrays (1)
- NDT Monitoring (1)
- NFDI-MatWerk (1)
- Nano-landscape (1)
- Nano-particles alignment (1)
- Nano-powder characterization (1)
- Nanofiller (1)
- Nanomaterial screening (1)
- Nanomaterials (1)
- Nanoparticel based pH-probes (1)
- Nanophysik (1)
- Nanopipette modification (1)
- Nanopipettes (1)
- Nanoplastics (1)
- Nanoporous media (1)
- Nanorisk (1)
- Nanosafety (1)
- Nanosensors (1)
- Nanostructures (1)
- Natural rubber (1)
- Nd-sensitizer (1)
- Nd3+ (1)
- Neintron diffraction (1)
- Neozoon (1)
- Netron diffraction (1)
- Network Communication (1)
- Neutronbeugungsverfahren (1)
- Neutronen (1)
- Neutronendiffraktion (1)
- Neutronenradiographie (1)
- Ni-base superalloy (1)
- Ni-based alloy (1)
- Nickel based alloy (1)
- Nickelbasislegierungen (1)
- Niobium carbide (1)
- Niobium carbide powder (1)
- Nitrogen (1)
- Non destructive testing (1)
- Non-Destructive Testing (1)
- Non-classical crystallization theory (1)
- Non-destructive testing (1)
- Normalbeton (1)
- Novel equipment (1)
- Nuclear Magnetic Resonance (1)
- Numerical Modeling (1)
- Numerical modelling (1)
- Numerische Simulation (1)
- OH Radical (1)
- OH radical scavenger (1)
- OH radicals (1)
- Oberflächenfunktionalisierung (1)
- Oberflächenkeimbildung (1)
- Offshore (1)
- One-part formulation (1)
- Online NMR Spectroscopy (1)
- Open data (1)
- Open science (1)
- Optical Assays (1)
- Optical Emission Spectroscopy (1)
- Optical Tomography (1)
- Optical connector (1)
- Optical criterion (1)
- Optical layer model (1)
- Optical properties (1)
- Optische Tomografie (1)
- Optoelektronik (1)
- Orientation-dependent microstructure (1)
- Orientierung (1)
- Osmolyte (1)
- Overlay (1)
- Oxide Glasses (1)
- Oxygen reduction reaction (1)
- P25 (1)
- P92 (1)
- PAEK (1)
- PDMS (1)
- PEG (1)
- PFAS (1)
- PH (1)
- PIM-1 (1)
- PMD Core Ontology (1)
- PMDco (1)
- POD (1)
- POSS (1)
- PU Learning (1)
- PVD /ECD process (1)
- Pair Distribution Functions (1)
- Pair distribution function analysis (1)
- Paracetamol (1)
- Partial discharge detection (1)
- Partial penetration (1)
- Particle Synthesis (1)
- Particle measurement (1)
- Particle scattering (1)
- Particle scattering simulations (1)
- Particle size (1)
- Particle size distribution (1)
- Particle size distributuion (1)
- Particle synthesis (1)
- Paste (1)
- Peem (1)
- Permeability (1)
- Permeation (1)
- Perovskite (1)
- Pharmaceuticals (1)
- Phase composition (1)
- Phasenzusammensetzung (1)
- Phosphate (1)
- Phosphonates (1)
- Phosphonic acids (1)
- Phosphorus (1)
- Photocuring (1)
- Photoluminescence (1)
- Photoresist (1)
- Photovoltaic (1)
- Phthalocyanine (1)
- Piezopolarisation (1)
- Pipeline (1)
- Plume (1)
- Politikberatung (1)
- Pollen (1)
- Polyacrylamide (1)
- Polyamid 12 (1)
- Polyaniline (1)
- Polyethylene Terephtalate (1)
- Polyethylene glycol diacrylate (1)
- Polyethylene terephthalate (1)
- Polyethylene, PE-HD (1)
- Polyglycerol (1)
- Polymer Hydrolysis (1)
- Polymer aging (1)
- Polymer coating (1)
- Polymer nanocomposites (1)
- Polymer optical fibers (1)
- Polymer optical fibre (1)
- Polymer-Ceramic-Composite (1)
- Polymeric membrane (1)
- Polymers of intrinsic microporosity (1)
- Polymethyl methacrylate (1)
- Polyurethan (1)
- Polyurethanes (1)
- Pore orientation (1)
- Pores (1)
- Porosity growth (1)
- Porosität (1)
- Porositätsvorhersage (1)
- Porous Materials (1)
- Porous materials (1)
- Portland cement (1)
- Position detection (1)
- Poster presentation (1)
- Postfluorination (1)
- Powder X-ray diffraction (1)
- Powder method (1)
- Preferred orientation (1)
- Pressure loading (1)
- Pressure tanks (1)
- Pressure wave (1)
- Primäre Explosionswirkug (1)
- Probenpräparation (1)
- Process Control (1)
- Processing (1)
- Propagation modes (1)
- Property simulation (1)
- Protective glazing (1)
- Protein a (1)
- Protein hydrolysis (1)
- Protein immobilization (1)
- Protein quantification (1)
- Protein unfolding (1)
- Proton conducting materials (1)
- Proton cunductor (1)
- Proton exchange membrane fuel cells (1)
- Proximatanalyse (1)
- Prozessmonitoring (1)
- Prozessregelung (1)
- Präparation (1)
- Prüfmethoden (1)
- Prüfrichtlinie (1)
- Pulse reflection (1)
- Pulse shape analysis (1)
- Pulvermethode (1)
- Py-GC/MS (1)
- QD (1)
- QSPR (1)
- Quality control (1)
- Qualitätsüberwachung (1)
- Quantitative Analysis (1)
- Quantitative NMR (1)
- Quantum Chemistry (1)
- Quantum Dot-Rod (1)
- Quantum Yield (1)
- Quartz Crystal Microbalance QCM (1)
- Quartz nanopipettes (1)
- Quasi-distributed sensing (1)
- Quenching and partitioning (1)
- Qulitätssicherung (1)
- RAFT (1)
- ROS (1)
- Radar (1)
- Radical Scavenger (1)
- Radical scavenger (1)
- Radicals (1)
- Radiografie (1)
- Radiological inspections (1)
- Raman spectroscopy (1)
- Rare earth nanoparticles (1)
- Ratiometric Sensors (1)
- Ratiometric sensors (1)
- Rauheit (1)
- Rayleigh scattering (1)
- Recycling (1)
- Reduction 4-nitrophenol (1)
- Reduction of agglomerates (1)
- Reductive amination (1)
- Reference Data (1)
- Reference Dataset (1)
- Reference materials (1)
- Reference nanomaterials (1)
- Reference particles (1)
- Reference procedures (1)
- Reference product (1)
- Reference samples (1)
- Registrierungsdossiers (1)
- Reinforcing Bar (1)
- Reinheitsgradbestimmung (1)
- Reliable characterization (1)
- Repair (1)
- Reproducibility (1)
- Research Data Management (1)
- Research data management (1)
- Residual stress measurements (1)
- Residual stress state (1)
- Residual stresses (1)
- Resonance (1)
- Resonanz (1)
- Reverse-time migration (1)
- Rice husk ash (1)
- Rigid amorphous fraction (1)
- Ringversuche (1)
- Risse (1)
- Rissprüfung (1)
- Risswachstum (1)
- Robot-assisted galss melting (1)
- Roboter (1)
- Round robin (1)
- Round robin test (1)
- Rubber (1)
- Röntgen-3D-Computertomographie (1)
- Röntgen-Refraktion (1)
- Röntgenbeugung (1)
- S-phase (1)
- SALSA (1)
- SDS-PAGE (1)
- SEM analysis (1)
- SEP 1927 (1)
- SIEF (1)
- SXRR - Synchrotron X-ray Refraction Radiography (1)
- Safe-by-Design (1)
- Safer by design (1)
- Salt melt (1)
- Sandblasting (1)
- Sandsteine (1)
- Sandstone (1)
- Sandstorm (1)
- Sanger sequencing (1)
- Sapphire (1)
- Sc-ICP-ToF-MS (1)
- Scaffold (1)
- Scale-bridging (1)
- Scanning electron microscopy (1)
- Scanning electron microscopy (SEM) (1)
- Scanning transmission electron microscopy (STEM) (1)
- Scattering (1)
- Schichtdicken (1)
- Schichtherstellung (1)
- Schichttestung (1)
- Schutzverglasung (1)
- Schwefelgehalt (1)
- Schweißdatenmanagement (1)
- Schweißnähte (1)
- Schwindungsinhomogenitäten (1)
- Schwindungsverhalten (1)
- Scientific software (1)
- Sea Water (1)
- Seenotrettungsmittel (1)
- Selbstreinigung (1)
- Selective Electron Beam Melting (1)
- Selective Laser Melting (1)
- Selective laser curing (1)
- Self-assembly (1)
- Self-healing silicone rubber (1)
- Self-powdering (1)
- Self-reactive substances (1)
- Semantic Data (1)
- Semi-metallic friction material (1)
- Sende-Empfangs Prüfkopf (1)
- Sensor (1)
- Sequential learning (1)
- Service life (1)
- Service life model (1)
- Shape (1)
- Shell (1)
- Short chained phthalates (1)
- Shortwave infrared (1)
- Si wafer filter (1)
- Si-Ge (1)
- SiGe (1)
- SiO2 (1)
- Silanisation (1)
- Silanization (1)
- Silica Nanoparticles (1)
- Silica- and Polystyrene Particles (1)
- Silica- and polystyrene particles (1)
- Silicone rubber (1)
- Silver (1)
- Silver nanoparticle (1)
- Simvastatin (1)
- Single cell analysis (1)
- Single crystal X-ray diffraction (1)
- Single cystal (1)
- Single-stranded DNA-binding proteins (1)
- Size and size distribution (1)
- Size effect (1)
- Size-exclusion chromatography (SEC) (1)
- Sliding performances (1)
- Slow Strain Rate Testing (1)
- Slow crack growth (1)
- Slurry (1)
- Small angle x-ray scattering (1)
- Small-angle X-ray scattering (1)
- Small-angle x-ray scattering (1)
- Small-angle xray scattering (1)
- Smart materials (1)
- Smouldering (1)
- Sodiumborosilicate glasses (1)
- Software (1)
- Soil (1)
- Soil-structure interaction (1)
- Solar Cell (1)
- Solarenergie (1)
- Solid-State-Reaction (1)
- Solution doping (1)
- Sorption (1)
- Spectral multiplexing (1)
- Spectrometry (1)
- Spectroscopic Ellipsometry (1)
- Spectroscopy (1)
- Speed of sound (1)
- Sphärische Indenter (1)
- Spinel (1)
- Spontane Polarisation (1)
- Spray drying (1)
- Sprengplattieren (1)
- Spring constant (1)
- Spruce (1)
- Stabilization of HT-structures at room temperature (1)
- Stabilizer (1)
- Stable suspensions (1)
- Stained glass windows (1)
- Stained glasses (1)
- Stainless Steel (1)
- Stainless Steels (1)
- Standard (1)
- Standardisation (1)
- Standardization (1)
- Standardization of Ellipsometry (1)
- Starch (1)
- Starch nanoparticle (1)
- Strain sensors (1)
- Stress cracking resistance (1)
- Strontiumfluoride (1)
- Structural color (1)
- Structural dynamics (1)
- Structural health monitoring (1)
- Subgrain structure (1)
- Submerged arc welding (1)
- Substrate effect (1)
- Sulfiding (1)
- Sulfur (1)
- Superalloy (1)
- Superconducting (1)
- Superhydrophilic surface (1)
- Superhydrophobic surface (1)
- Superplasticizer (1)
- Superplasticizers (1)
- Surface Chemical Transformation (1)
- Surface Energy (1)
- Surface Plasmon Resonance (1)
- Surface characterization (1)
- Surface crystallization (1)
- Surface energy (1)
- Surface functionalities (1)
- Surface group analysis (1)
- Surface morphology (1)
- Surface structuring (1)
- Surface texturing (1)
- Sustainability (1)
- Synchrotron CT (1)
- Synchrotron Radiation (1)
- Synchrotron Tomography (1)
- Synchrotron X-ray Refraction (1)
- Synchrotron X-ray diffraction (1)
- Synchrotron X-ray refraction (1)
- Synchrotron X-ray refraction radiography (1)
- Synchrotron XRD (1)
- Synchrotron radiation (1)
- Synchrotron refraction radiography (1)
- Synthesizability (1)
- Synthetic air (1)
- TATP (1)
- TBC (1)
- TDLAS (1)
- TED-GC-MS (1)
- TEKKEN-Test (1)
- TEM Image (1)
- TGA-FTIR (1)
- THz and mid IR spectroscopy (1)
- THz spectroscopy (1)
- TIG-welding (1)
- TKD (1)
- TMDSC (1)
- TMF (1)
- TRIP (1)
- TRIS (1)
- Talbot-Lau interferomerty (1)
- Talbot-Lau interferometry (1)
- Tankdesign (1)
- Tauchwägung (1)
- Technical Lignin (1)
- Temeprature scaling (1)
- Temperature dependence (1)
- Temperature scaling (1)
- Tensile (1)
- Tensile Properties (1)
- Tensile test (1)
- Terahertz Tomography synthetic aperture (1)
- Terahertz synthetic aperture dielectric materials (1)
- Termites (1)
- Ternary quantum dot (1)
- Test method (1)
- Test methods validation (1)
- Test procedure (1)
- Testing (1)
- Textile fibres (1)
- Texture (1)
- Themal Transitions (1)
- Thermal Spray (1)
- Thermal arrier coatings (1)
- Thermal barrier coatings (1)
- Thermal cycling (1)
- Thermal decomposition (1)
- Thermal treatment (1)
- Thermodynamic analysis (1)
- Thermoelectric generator design (1)
- Thermoelectric oxides (1)
- Thermomagnetic material (1)
- Thermomechanics (1)
- Thermoplastic Polyurethane (1)
- Thermoresponsive polymer (1)
- Thermoresponsive polymers (1)
- Thickness (1)
- Thin Films; (1)
- Thin polymer films (1)
- Ti6Al4V alloy (1)
- TiO2 nanoparticle (1)
- Time-offlight Diffraction (TOFD) (1)
- Time-offlight secondary ion mass spectrometry (ToF-SIMS) (1)
- Time-resolved (1)
- Titania nanoparticles (1)
- Titanium Dioxide (1)
- Titanium nitride (1)
- Titanium-di-boride (1)
- Titration (1)
- Tomographie (1)
- Tomography (1)
- Tool steel (1)
- Topas (1)
- Topas-MC (1)
- Topas-nBio (1)
- Topografie (1)
- Topography (1)
- Topometry (1)
- Torsional fatigue (1)
- Total scattering analysis (1)
- Transmission Kikuchi Diffraction (TKD) (1)
- Transmission electron microscope (TEM) (1)
- Transmittance (1)
- Transport mechanism (1)
- Tribological behavior (1)
- Tribologie (1)
- Trinkwasser (1)
- Tunnel (1)
- Two photon polymerisation (1)
- Two-dimensional liquid chromatography (2D-LC) (1)
- Type III composite pressure receptacles (1)
- Tyrosine (1)
- UCNP (1)
- UCST polymers (1)
- UCST-type polymer (1)
- UPLC (1)
- UV Weathering (1)
- UV-irradiation (1)
- Ultra sound (1)
- Ultrafast laser processing (1)
- Ultraschall (1)
- Ultraschalltauchtechnik (1)
- Ultrasonic (1)
- Ultrasonic Testing (1)
- Ultrasonic Transducer (1)
- Ultrasonic assisted milling (1)
- Ultrasonic echo technique (1)
- Uncertainty (1)
- Uncertainty budgets (1)
- UpConversion (1)
- Upconversion nanoparticles (1)
- Upconverting nanoparticles (1)
- VM12 SHC (1)
- Vacuum (1)
- Vacuum hot extraction (1)
- Vakuumheißextraktion (1)
- Validation (1)
- Verbundwerkstoffe (1)
- Vereinfachtes Verfahren (1)
- Vergleichsstahlproben (1)
- Vernetzte Produktion (1)
- Verzinkungen (1)
- Videoskopie (1)
- Virtual experiments (1)
- Vitual computer tomography simulation (1)
- Volatile organic compounds (1)
- WIG-Blindschweißnaht (1)
- Waiting time (1)
- Wasseraufbereitung (1)
- Wasserstoffpermeation (1)
- Waste heat recovery (1)
- Water/alcohol mixtures (1)
- Wave propagation (1)
- Weld Joint (1)
- Wellenprüfung (1)
- White light interference microscopy(WLIM) (1)
- Widerstandpunktschweißen (1)
- Windkanal (1)
- Wood preservation (1)
- Workflow (1)
- X-Ray Diffraction (1)
- X-ray Computed Tomography (1)
- X-ray Diffraction (1)
- X-ray computer tomography (1)
- X-ray diffractometry (1)
- X-ray imaging (1)
- X-ray interferometry (1)
- X-ray scattering (1)
- X-ry Diffraction (1)
- XAS (1)
- Yb(III) (1)
- Yellowing (1)
- Young's modulus (1)
- Young´s modulus (1)
- Zahnmedizin (1)
- Zelluläres Polypropylen (1)
- Zement (1)
- Zementgebundene Baustoffe (1)
- Zentrifugentechnologie (1)
- Zeolite (1)
- Zersetzungsgasanalyse (1)
- Zerstörungsfreie Prüfung (1)
- Zinc and galvanized samples (1)
- Zirconium (1)
- ZnSe (1)
- Zonation (1)
- Zugversuch (1)
- Zuverlässigkeit (1)
- Zünder (1)
- additive manufacturing (1)
- aggregation-induced dual emission (AIDE) (1)
- bioimaging (1)
- burst test (1)
- cocrystal (1)
- creep behaviour (1)
- dangerous goods packagings (1)
- depth-profiling (1)
- excess isotherms (1)
- excitation power density (1)
- extreme temperature (1)
- fluorine (1)
- gas adsorption (1)
- gas solubility (1)
- high-resolution camera (1)
- hybrid repair (1)
- ionic liquids (1)
- life cycle test (1)
- low energy electrons (1)
- mechanochemistry (1)
- milling (1)
- pH probe (1)
- pH sensing (1)
- polyethylene terephthalate (1)
- porous solids (1)
- position detection (1)
- powder bed fusion of metals utilizing a laser beam (1)
- ssDNA (1)
- stress cracking resistance (1)
- test methods (1)
- µ-FTIR (1)
- µ-Raman (1)
- µ-XRF (1)
- µCT (1)
- Örtliche Korrosion (1)
- β-cristobalite structure type (1)
Organisationseinheit der BAM
- 6 Materialchemie (203)
- 5 Werkstofftechnik (97)
- 8 Zerstörungsfreie Prüfung (95)
- 6.3 Strukturanalytik (65)
- 8.5 Röntgenbildgebung (60)
- 6.6 Physik und chemische Analytik der Polymere (55)
- 9 Komponentensicherheit (53)
- 1 Analytische Chemie; Referenzmaterialien (45)
- 6.1 Oberflächen- und Dünnschichtanalyse (44)
- 4 Material und Umwelt (36)
Eingeladener Vortrag
- nein (1)
Due to their chemical structure, a rigid disk-like aromatic core and flexible alkyl chains attached to the core, discotic liquid crystals (DLCs) can organize and stack themselves into columns in a hexagonal columnar mesophase, a mesophase in between the plastic crystalline and isotropicphase. The overlap of the π orbitals of the aromatic core in the hexagonal columnar mesophase leads to a high charge-carrier mobilitie along the column axis – these columns can be considered as “moleculer nanowires” making liquid crystals a promising class of materials for electronic applications. Previous studies on DLCs showed that the phase behavior of DLCs is susceptible to nano confinement. Here in this study, the thermotropic collective orientational order of 2,3,6,7,10,11 hexakis[hexyloxy] triphenylene (HAT6), a triphenylene based DLC, and the effects of nano confinment on of its phase behavior were investigated by broadband dielectric spectroscopy (BDS) and differential scanning calorimetry (DSC). HAT6 was embedded into nanoporous anodic aluminum oxide membranes by melt infiltration in the isotropic phase under argon atmosphere. The filled membranes have the thickness of 80 µm and the diameter of 15mm and parallel aligned tubular nanopores having the pore diameters of 25, 40, 80 and 180 nm. The filling degree for each sample was checked by thermogravimetric analysis (TGA) in order to ensure complete filling. The bulk HAT6 forms, a hexagonal columnar phase between the isotropic phase above 371 K, and the plastic crystalline phase below 340 K. Unlike the bulk, the confined HAT6 forms two peaks in the heat flow during the plastic crystalline-to-hexagonal columnar phase transition, which might be the evidence of two different phase structures close to the wall and in the pore center. Moreover, the isotropic-to-columnar transition of the confined HAT6 shifts with decreasing pore diameter to lower temperatures.
Advanced methods for 3D green density characterization like computed tomography and 3D FE sinter modeling can be utilized for increasing the reliability of sintered components. The experimental in situ observation of sintering, however, is currently restricted to silhouette methods, i.e. heating microscopy. For complex shaped samples, in situ shape screening during shrinkage would allow much better validation of 3D sinter simulation models. Further, by revealing temporary sinter warpage, 3D high-temperature shape screening would allow to locate potential defects of complex sintered components. Against this background, BAM developed a testing device for in situ 3D high-temperature shape screening for ceramic and glass-ceramic tapes up to 1000°C. Current work is focused on dropping this restriction in sample shape and temperature. The poster illustrates the current state of this work and possible applications of the method e.g. in detecting sinter warpage of metallized glass-ceramic LTCC tapes.
In times of the energy revolution, the need for energy efficient separation processes promotes the advancement of new high performance materials for use as highly selective separation membranes. Most promising materials in this field, especially for gas separation, are polymers with intrinsic microporosity (PIMs) which were firstly introduced by Budd and McKeown. In this study the permeability of PIM-1 was increased by 439 % by formation of nanocomposites with only 1 wt% of polyhedral oligomeric phenethyl-silsesquioxane (PhE-POSS) within the polymer matrix. As the CO2/CH4 selectivity is fully retained, this leads to a shift in the Robeson plot towards the upper bound. The Robeson plot describes the current state of the art trade-off relation between selectivity and permeability of all known membrane polymers. As molecular mobility is a key factor for gas transport as well as the often observed physical aging of such polymers, our study also includes for the first time, molecular dynamics and conductivity of pure PIM-1 and PIM-1 nanocomposites as investigated by broadband dielectric spectroscopy (BDS).
Mechanical characterization of high-density polyethylene in contact with diesel and biodiesel fuels
(2016)
Renewable resources become more and more relevant to maintain energy demands for an increasing global population. Biosynthetic fuels like biodiesel might replace conventional petrochemical fuels, such as diesel. However, more research is needed to characterize the interaction between the different fuels and polymeric materials widely used in the fuel infrastructure as well as for automotive parts. Especially changes in the structural properties and mechanical behavior of the polyethylene (PE-HD) have to be addressed.
The presented work comprises the direct interaction of high density polyethylene (PE-HD) with diesel and biodiesel, resulting in swelling and plasticization. Also long-term degradation phenomena will be discussed.
The chosen PE-HD types are typical thermoplastic resins for container and storage tank applications. The impact of diesel and biodiesel in PE-HD is investigated by changes in the mechanical properties with emphasis on the Charpy impact strength. Furthermore, structural and dynamic influences on the polymeric material induced by diesel and biodiesel are proven in Dynamic Mechanical Analysis (DMA). Both methods, Charpy impact strength and DMA, reveal softening effects due to the migration of diesel and biodiesel into the amorphous regions of PE-HD.
Since biodiesel is more prone to oxidative degradation compared to diesel, the fuel/air/polymer-interaction is studied for partly immersed tensile test specimens. Main focus of the evaluation is the co-oxidation. Here, the accelerated deterioration of PE caused by the sorption of the facile oxidation of biodiesel into the solid polymer might be a major degradation mechanism in this context.
Characterization of statistical EO-PO copolymers containing different end groups by UPLC/ESI-MS
(2016)
Commercial statistical ethylene oxide (EO) and propylene oxide (PO) copolymers of different monomer compositions and different average molar masses were studied by liquid chromatography under critical conditions (LCCC). Theoretical predictions of the existence of a critical adsorption point (CPA) for statistical copolymers with a given chemical and sequence distribution, could be studied and confirmed. An improved way to determine these critical conditions in a copolymer, alongside the inevitable chemical composition distribution (CCD), with the aid of mass spectrometric detection is described. Shift of the critical eluent composition with the monomer composition of the polymers could be observed. Due to the relatively low average molecular weight, broad molecular weight distribution (MWD) and the presumed existence of different end group functionalities as well as sequence distribution, gradient separation only by CCD was not possible. Therefore isocratic separations at the CPA of definite CCD’s were applied. Although the various present distributions partly superimposed the separation process the goal of separation by end group functionality could still be achieved on the basis of the additional dimension of ESI-MS. The existence of HO-H besides the desired AllylO-H end group functionalities could be confirmed and their amount could be estimated.
Materials that respond to the environment by changing their properties are critical for developing
autonomously adaptive systems. However, to reversibly influence a material's inherent characteristics, such as its ability to self-heal, from distance without continuously expending energy, remains a challenging task. Herein, we report on the modul at ion of imine exchange kinetics by light, manifested in a remote controllable dynamic covalent polymer network. Simple mixing of a commercially available amino-functionalized polysiloxane with small amounts of a photoswitchable diarylethene cross-linker, carrying two aldehyde groups, yields a rubbery material. Its viscoelastic and self-healing properties can be reversibly tuned with everyday light sources, such as sunlight. Our two-component system offers the unique advantage that self-healing takes place continuously without any additives at ambient conditions and is neither dependent on continuous illumination nor does it require recent damage. Overall, our approach allows for the local amplification of intrinsic material properties in a permanent yet reversible fashion. The availability of the inexpensive sta1ting materials on a multi-gram scale, the easy synthesis of the polymer network, and its convenient handling paired with high versatility make our Approach highly applicable to create custom-tailored adaptive materials.
Healable materials are able to repair inflicted damages, herin often applied: dynamic covalent polymer networks. We have shown in this study that light of different colors shift the Diels-Alder and retro Diels-Alder crosslinking and decrosslinking equilibrium. This effect was utilized for self-healing of a polymer film. Small-angle X-ray scattering was used to quantifiy the polymeric mesh size on a nanoscale.
Calcium cobaltite is a promising p-type oxide thermoelectric material for high temperature applications due to its high figure of merit between 600 °C and 900 °C in air. The solid-state-reaction is well known for large scale powder synthesis of functional materials. As a high temperature process, the powder synthesis consumes a lot of energy. In different studies, different synthesis conditions were used for the preparation of calcium cobaltite powder. This study showed that a higher energy input (elevated temperatures, longer dwell times, or repeated calcinations) during powder synthesis does not increase but decrease the Seebeck coefficient and the electrical conductivity. The same correlation was determined for the densification. As a higher energy input leads to a larger grain size and therefore to a reduced sinter activity, it can be concluded that the thermoelectric properties are correlated with the sinter activity of the powder. These results can be used to minimize the energy demand for the powder synthesis of Ca₃Co₄ O₉.
Multilayer carbon nanomembrances (CNMs) could pave the way for a new ultrathin functional conductive coatings with tunable electrical, optical, and chemical properties. Due to their molecular thickness, they can also be regarded as “interfaces without bulk” separating regions of different gaseous, liquid, or solid components and controlling the materials exchange between them, making them optimal materials for membranes applications. Furthermore, their physical and chemical properties depend strongly on their structure, molecular composition, and the surroundings of either sides, thus allowing for tailored properties. Here, nanolayers of Aromatic p-terphenylthiol (TPT) self-assembled into 2D carbon monolayers (thickness - 1.6 nm) were synthesized and further crosslinked by ion bombardment, forming CNMs. Here, though a recently developed multilayer nanosheets routine, stacks of 5, 10, 15 and 20 TPT sheets where transferred on top of each other forming a multilayered CNMs. However, this transfer routine could introduce some intrinsic defects to the sheets, which would alter the molecular composition and / or structure, thus consequently the CNMs properties. Therefore, it is essential to characterize defects in “pure” TPT nanomembranes, before tailoring the molecular compositions, e.g. adding functional groups. For this reason, broadband dielectric spectroscopy (BDS) was utilized to characterize any defects that could be rasied during preparation. Due the structure of pure TPT membranes, no dipole moment should exsist. However, the presence of other elements, e.g. water or sulphur, would result in a dipole moment that could be probed by BDS.
As a main result, for all different stacked-layer numbers, a clear relaxation process is seen, which moves to higher frequencies with increasing the temperature. The temperature dependence of the relaxation rate of this process is independent of film thickness and can be well described by a common VFT function, hence a corporative motion. This relaxation process was assigned to intrinisic defects in the membranes, introduced during preparation, which was further confimed by a detailed anaylsis of the dielectric strength. This is the first BDS measurment on TPT CNMs.
Many engineering structures are made of composite materials or metal foam. To simulate the deformational behaviour of these structures often requires a high number of discretisation elements. This in turn yields a very large system of linear
equations that are extremely time and memory consuming or practically impossible to solve. It is therefore desirable to find an approach to overcome this obstacle.
Many engineering structures are made of composite materials or metal foam. To simulate the deformational behaviour of these structures often requires a high number of discretisation elements. This in turn yields a very large system of linear equations that are extremely time and memory consuming or practically impossible to solve. It is therefore desirable to find an approach to overcome this obstacle.
In the presentation different zinc coatings are presented and investigated. Their naturally formed protective layers are electrochemically characterized and corrosion relevant values are determined by using a gel pad based on polysaccharide. The corrosion relevant values allow the differentiation of various zinc coating systems and can describe the current protective effect provided by the coating. It is shown that gel-type electrolytes influence protective layers and coatings considerably less than corresponding bulk electrolytes. From the results it is evident that gel-type electrolytes represent a viable and promising field in corrosion research.zeige mehr
Deuterium permeation and cracking in duplex steels as viewed by ToF-SIMS and HR-SEM with data fusion
(2016)
Better understanding of hydrogen assisted degradation and trapping mecha-nisms requires sufficient imaging techniques for respective hydrogen-microstructure interaction studies, in particular with multi-phase metallic micro-structures [1]. The present work is focusing on the elucidation of deuterium be-havior in two austenitic-ferritic duplex stainless steels (DSS) under the assumption that deuterium behaves in many ways similarly to hydrogen [2]. For case studies standard 2205 and lean 2101 DSSs were chosen due to the extensive use of these steels in industry [3]. The analyses were conducted by using a novel in-situ permeation and Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) imaging technique or by ex-situ ToF-SIMS imaging following electrochemical charging experiments. Another pioneering procedure was data fusion (including chemometry) of results of powerful laterally resolved chemical analysis and high resolution structural characterization techniques .
Results for the ex-situ observations showed a different influence of deuterium loading on the two steel grades as well as different damage mechanisms in each phase. Formation of sub-surface blisters between the ferrite and austenite were obtained in both the standard and the lean DSS. In both steels, an increased deuterium concentration was observed around deformed regions such as cracks, confirming that they originate from the presence of deuterium [4]. The formation of parallel cracks was obtained only in the austenite within the standard duplex whereas in the lean duplex the highest intensity of deuterium was obtained in the austenite along the ferrite-austenite interphase.
In comparison, application of the novel in-situ permeation technique enabled to register and record the deuterium permeation through the material and the respective saturation sequence of the two phases as well as the interfaces. Faster diffusion of the deuterium was observed in the ferrite and a direct proof for deuterium enrichment at the austenite-ferrite interface has been given [1]. The integration of the specified techniques gives a better insight into the processes leading to hydrogen induced failure. These two experimental techniques provide very valuable tools for elucidation of respective metallurgical failure mechanisms that can be used for the validation of respective numerical models for hydrogen assisted cracking (HAC).
The chemical industry has expressed great interest in using polyethylene terephthalate (PET) as material for packagings for the transport of dangerous goods. Due to the high strength and stiffness of PET, the wall thickness and weight of packagings can be reduced. This is a relevant cost factor. PET is a semi-crystalline thermoplast which is produced by polycondensation of terephthalic acid and ethylene glycol.
According to the European dangerous goods regulations RID and ADR, samples of PET design types of packagings for dangerous goods must be pre-stored with the original filling good for six months at 23°C, before the design type tests can be carried out. For packagings made of polyethylene (PE) tests to prove the stress cracking resistance by using laboratory methods are possible to reduce time and costs. Therefore, standard liquids, simulating the different types of damaging effects on PE are defined in RID and ADR. However, there is no information and research available about the damaging mechanisms on PET in comparison to PE, especially regarding to stress cracking resistance and test methods.
The aim of this work is to compare the stress cracking resistance of PE and PET with the Full Notch Creep Test (FNCT), which was developed by chemical industry and is described in the standards EN ISO 16101 and EN 15507. It was investigated whether testing specimens made of PE and PET with a full coplanar notch around the middle of the specimens show weakening after the impact of a tensile force in a wetting solution (Lutensol® FSA 10) at 50°C in a test device on the basis of the FNCT.
The test results confirmed the suitability of the method for eight PE grades. Unfortunately, this method couldn’t be used for PET because the specimens broke during notching. In addition the molding of the sheets and the following temper process for twelve hours are very time-consuming, and the specimens broke during notching due to the high brittleness of PET.
Another possibility to provide evidence of stress cracking resistance of PE packagings is laid down in BAM’s Dangerous Goods Rule BAM-GGR 015. This test was carried out with PE and PET bottles to compare both materials. Therefore 1l test bottles were filled with a 5% wetting solution and mounted with a clamping tool for 28 days at 40°C. Tensile test specimens were cut out afterwards from the middle of the bottles in the deformed areas. Tensile strength and breaking elongation of PE specimens were determined in comparison to the PET specimens. The tensile properties of the PET specimens couldn’t be determined due to the strength and the stiffness of the material.
In conclusion the only way to provide information about the stress cracking resistance of PET was to perform stacking tests. 1l bottles made of PE and PET were filled with a 5% wetting solution and stored with a stacking load for 28 days at 40°C according to EN ISO 16495. Design types of PE and PET both passed the stacking tests.
Hydrogen-assisted cracking (HAC) represents a significant failure risk for (high strength) creep resistant low-alloyed steel components in fossil-fired power plant applications at temperatures of up to and above 200 °C. This particularly applies to respective start-up and shut-down processes associated with alternating service-conditions in terms of load flexible power plants. For quantitative determination of localized crack critical hydrogen concentrations, the temperature dependent hydrogen diffusion coefficients have to be determined as exactly as possible.
However, available literature provides a wide range of hydrogen diffusion coefficients for low alloyed steels with similar microstructures. Additionally, the available diffusion data seem not to be very reliable and their scatter increases with decreasing temperature. One reason is that the experimental boundary conditions can have a major impact on the determination of respective effective diffusion coefficients. Hence, the scope of this study is to evaluate the influence of the experimental boundary conditions on the derived diffusion coefficients. In addition, different methods for calculating diffusion coefficients are discussed. To elucidate such influences and to draw a line to practical application, the diffusion and trapping behavior in the creep resistant steel 7CrMoVTiB10 10 has been studied.
For such purpose, hydrogen charged specimens were isothermally degassed at different temperatures using carrier gas hot extraction (CGHE). Based on experimental data, a numerical model has been developed by which the hydrogen transport behavior and the respective hydrogen distribution during CGHE can be assessed.
It is demonstrated that the specimen heating rate has a large influence on the calculated diffusion coefficients under assumption of isothermal degassing which elsewhere has been underestimated in the assessment of diffusion data in creep-resistant steels. The numerical results suggest that calculation methods for diffusion coefficients are limited if compared to experimental results. It also turned out that the sample preparation time before CGHE can enormously influence determined diffusion coefficients. Consequently, non-homogeneous hydrogen concentration profiles have to be anticipated in the simulations to arrive at characteristic effusion curves consistent to respective CGHE experiments. In turn, validated diffusion coefficients are now available for the low-alloyed Cr-Mo-V steel, which can be helpful to calculate appropriate hydrogen removal heat treatment procedures.
A test campaign was launched to determine the mechanical properties of the HL-LHC 11 T Nb3Sn magnet components in order to accurately model the mechanical properties in Finite Element simulations that predict the stress and strain distribution in These magnets. Static and dynamic test methods have been applied for determining elastic materials behavior, and highly accurate Young’s moduli are obtained with the dynamic methods resonance and impulse excitation. These non-destructive methods also enable temperature dependent modulus measurements during in situ heat cycles.
Hydrogen-assisted cracking (HAC) represents a significant failure risk for (high strength) creep resistant low-alloyed steel components in fossil-fired power plant applications at temperatures of up to and above 200 °C. This particularly applies to respective start-up and shut-down processes associated with alternating service-conditions in terms of load flexible power plants. For quantitative determination of localized crack critical hydrogen concentrations, the temperature dependent hydrogen diffusion coefficients have to be determined as exactly as possible.
However, available literature provides a wide range of hydrogen diffusion coefficients for low alloyed steels with similar microstructures. Additionally, the available diffusion data seem not to be very reliable and their scatter increases with decreasing temperature. One reason is that the experimental boundary conditions can have a major impact on the determination of respective effective diffusion coefficients. Hence, the scope of this study is to evaluate the influence of the experimental boundary conditions on the derived diffusion coefficients. In addition, different methods for calculating diffusion coefficients are discussed. To elucidate such influences and to draw a line to practical application, the diffusion and trapping behavior in the creep resistant steel 7CrMoVTiB10 10 has been studied.
For such purpose, hydrogen charged specimens were isothermally degassed at different temperatures using carrier gas hot extraction (CGHE). Based on experimental data, a numerical model has been developed by which the hydrogen transport behavior and the respective hydrogen distribution during CGHE can be assessed.
It is demonstrated that the specimen heating rate has a large influence on the calculated diffusion coefficients under assumption of isothermal degassing which elsewhere has been underestimated in the assessment of diffusion data in creep-resistant steels. The numerical results suggest that calculation methods for diffusion coefficients are limited if compared to experimental results. It also turned out that the sample preparation time before CGHE can enormously influence determined diffusion coefficients. Consequently, non-homogeneous hydrogen concentration profiles have to be anticipated in the simulations to arrive at characteristic effusion curves consistent to respective CGHE experiments. In turn, validated diffusion coefficients are now available for the low-alloyed Cr-Mo-V steel which might be helpful to calculate appropriate hydrogen removal heat treatment procedures, for instance.
Modeling of Hydrogen-Assisted Cracking (HAC) in Duplex Stainless Steels (DSS):
- Hydrogen causes significant degradation in DSS and consequently HAC
- Mechanisms of HAC have not been fully understood in two-phase microstructures
- Mesoscale numerical modeling for HAC in DSS was created, coupled to the macroscale, enabling simulation of HAC in both phases independent from predefined crack paths
Renewable resources become more and more relevant to maintain energy demands for an increasing global population. Biosynthetic fuels like biodiesel might replace conventional petrochemical fuels, such as diesel. However, more research is needed to characterize the interaction between the different fuels and the polymeric material, especially with respect to ageing and degradation.
The poster will present several interaction and degradation phenomena of high density polyethylene (PE-HD) induced by diesel and biodiesel 1-3. Also the possible influence of microbial growth (fungi and bacteria) is considered. The chosen PE-HDs are typical thermoplastic resins for container and storage tank applications. Degradation of PE-HD will be investigated by changes of the mechanical properties – with main emphasis on the Charpy impact strength 2. Furthermore, with alternating sorption and desorption cycles in combination with oven ageing the co-oxidation 3 of PE-HD in contact with biodiesel will be addressed.
The widespread use of antibiotics in livestock farming leads to trace residues in food products and wastewater, potentially entailing antimicrobial resistance in food-borne pathogens. The determination of antibiotics in aqueous environments and foodstuff is thus of major concern.
Analytical assays based on molecularly imprinted polymers (MIPs) have emerged as a valuable tool in this field due to the low production costs, stability, format adaptability and the possibility to imprint and thus their ability to recognize a wide variety of target analytes. With regard to optical sensing technologies, however, MIPs have only been used in considerably few applications, especially in fluorescence sensors. This limitation is basically due to the fact that the incorporation of a fluorescently responding moiety into a polymer matrix is challenging. One way to overcome this limitation is to use tailor-made fluorescent indicator monomers for direct transfer of the binding event into an optical signal. If such a monomer is integrated into a thin MIP-shell on microspheres such core/shell particles can be readily used in advanced multiplexing sensory fiber-optic microarrays.
Here, we propose such a fiber-optic microarray based on fluorescent MIP microspheres for antibiotics. The binding behavior and the selectivity of a microarray using these MIP were examined and compared with a non-imprinted polymer (NIP) control, employing the target molecules and other structurally closely related antibiotics.
Metal reducing bacteria (MRB) are able to utilize various materials such as iron, uranium and manganese as well as many organic compounds as electron acceptors. This process leads to the conversion of Fe(III) containing passive film species to soluble Fe(II) oxides and hydroxides. The reduction process triggers the acceleration of general and local corrosion processes. Electron transfer mechanisms are not yet fully understood. In literature it has been controversially discussed to which extend secreted electron shuttles contribute to the extracellular electron transfer (EET).
To understand the chemical and electrochemical interaction mechanisms of MRB with steel surfaces this project combines a variety of in-situ techniques. The changes in oxide chemistry on Fe/steel surfaces in the presence of biomolecules and MRB are under investigation using a newly designed electrochemical cell for in situ XANES (x-ray absorption near edge structure) spectroscopy. Electrochemical quartz crystal microbalance (eQCM) studies support the spectroscopic investigations to gain information about the kinetics of attachment processes and changes in biofilm viscosity. The biofilm structure and composition as well as cell viability are investigated by complementary ex situ spectroscopic and microscopic analysis.
Combining spectroscopic techniques and eQCM data with electrochemical measurements, biological processes and the resulting degradation of steel surfaces can be observed in a non-destructive manner. Selecting model systems and a defined biological medium allows the determination of individual effects of diverse surface and environmental parameters. The fundamental understanding of bacterial attachment mechanisms and initial steps of biofilm formation will contribute to the development of new antifouling strategies.
In recent years, upconversion nanocrystals (UCNC) have shown great promise for biological and medical applications, mainly because of their excitation in the NIR region, which provides minimum fluorescence background and a rather deep penetration into biological samples, as opposed to excitation in the visible or UV region. Moreover, they show a multitude of characteristic narrow emission bands as basis for ratiometric measurements. Commonly, Yb is the sensitizer of choice, because of a comparatively high absorption cross section, simple energy scheme, and rather efficient energy transfer to the activator, mostly Er, Tm or Ho. A main disadvantage of the use of Yb as sensitizer for biological and medical applications is its absorption band at 976 nm and hence the use of an excitation wavelength at which water has a non-negligible absorption. This can lead to significant sample heating, especially at long illumination times or high excitation power densities, and thus, tissue damage or even cell death. A possible solution is the tri-doping of UCNC with Nd as sensitizer, which can be excited efficiently at around 800 nm, where water absorption is at minimum.
The use of Nd as a sensitizer and Yb as a bridge between Nd and the activator Er in NaYF₄ nanocrystals is a relatively new way to overcome the problems of heating of samples in an aqueous environment. Disadvantages can arise from the tri-doping, which can favor non-radiative relaxation due to the more complicated excitation process compared to e.g., simple Yb,Er-doped UCNC, which might lower the upconversion quantum yields in these tri-doped systems. In order to quantify clear advantages, NaYF₄:Yb,Er,Nd nanoparticles were synthesized and spectroscopically studied using an 8 W 804 nm laser diode and a custom-designed Edinburgh instruments FSP980 spectrometer. Wavelength-dependent studies of the emission intensities and the decay kinetics of these tri-doped UCNC at different excitation power densities and excitation pulse widths revealed the clear advantages of preventing water absorption on measurable luminescence signals.
We were able to show the influence of pulse width and excitation power density on the luminescence intensities and decay kinetics lifetimes at different emission wavelengths. Additionally, we can clearly discern power density-dependent and independent peaks in the emission spectra. In summary, we demonstrate that the tri-doping of NaYF₄:Yb,Er,Nd nanoparticles is a very promising approach to render UCNC more efficient and to make them better suitable for biological and medical applications requiring measurements in aqueous environment.
Silicon surface passivation with atomic layer deposited (ALD) thin films has gained more and more interest in the PV community in recent years. With ALD good film quality, accurate thickness control and conformity are reached. Furthermore, ALD is capable of coating difficult substrates such as nanostructured surfaces with the same accuracy as flat surfaces. A variety of materials such as Al2O3, TiO2 and HfO2 demonstrate good surface passivation quality both for front and rear surface of silicon solar cells. In addition of providing good surface passivation, thin films with high refractive index e.g. HfO2, TiO2 and AlN can act simultaneously as antireflection coatings when applied on the front surface of the device. Hence, ALD thin films can reduce both electrical and reflective losses in solar cells.
Thorough investigation of the optical properties of these layers is crucial for several reasons related to their production and use. Optical measurements provide a fast, easy, non-destructive, and in situ capable approach to quality assurance for photovoltaic devices. As the function of the final device is optical, optimisation of the device performance relies strongly on the knowledge of the wide-range dielectric function of the thin layers. In this contribution, we determined the optical constants of ALD generated layers of AlN, Al2O3, TiO2, and HfO2 in a wide spectral range covering the near ultraviolet and the mid-infrared regions by means of spectroscopic ellipsometry. By combining data from a UV-Vis-NIR ellipsometer (Woollam M2000DI) and an FTIR ellipsometer (Sentech Sendira), we can determine the optical constants alongside with the layer thicknesses from one large set of spectroscopic measurements. We consider this a contribution to the metrological treatment of stratified and structured thin films in the optical range by polarisation-sensitive measurement methods.
By means of an effective medium (EMA) based approach, it is possible to use spectroscopic ellipsometry to determine the mixing ratios between air and material in porous dielectrics and calculate a quantitative value of the porosity for these materials. As this method is model-based, it is very difficult to provide a quantitative measure for the accuracy of porosity values determined by this method. Valuable additional information can often be obtained by combining ellipsometry with other complementary methods. In the present study, the ellipsometry results were validated by Electron Probe Microanalysis (EPMA) with the option of layer analysis (by the socalled “STRATAGem” approach), gravimetry, and electron microscopy. We analysed porous TiO2 thin layers synthesised by means of a template synthesis approach (evaporation induced self assembly).
Ellipsometry measurements on porous samples are difficult to analyse due to the complexity of the models necessary. Often it is difficult to decide if the measured data contains enough information to successfully determine the target quantities (mixing ratio, dielectric function of the matrix material). One method to decrease the complexity of the fit and therefore use the measurement data most efficiently is a multi-sample analysis. In the present case, multi-sample analysis was used for determining the porosity factors of the individual layers while using one common set of dielectric function values for the matrix in all cases.
While the results of the fit analysis in this case can be used to show the feasibility and also the limitations of the multi-method approach, the porosity values themselves show a promising agreement between the independent methods. It can therefore be concluded that determining porosity values with ellipsometry is in accordance to other methods to the level of accuracy provided by the complementary methodologies.
Microbial induced corrosion (MIC) is a crucial problem in many technical plants as well as fuel tanks, leading to considerable damage and huge financial losses. Successful prevention of MIC requires the localization of first signs of corrosion as well as the identification of factors influencing the corrosion process.1 Hence, there is a growing need for sensitive and preferably inexpensive tools that enable the early detection of MIC. Of high importance are methods, which provide spatially and time-resolved information and allow the study of changes on metal surfaces as prerequisites for a more detailed analysis of ongoing corrosion processes at a MIC-affected site.2 In this respect, also the determination of corrosion rates can be of interest for the possible prevention of MIC.
Beton ist als Massenbaustoff vielseitig einsetzbar. Eine der neuesten Entwicklungen ist Ultrahochleistungsbeton (UHPC). Seine besonderen Eigenschaften ermöglichen eine zusätzliche Funktionalisierung der Oberflächen, da annähernd beliebige Mikrostrukturen exakt abgeformt werden können. So lassen sich beispielsweise Fassadenelemente aus UHPC bereits bei ihrer Herstellung im Betonfertigteilwerk mit selbstreinigenden Oberflächen ausrüsten. Eine andere Möglichkeit ist eine Anwendung als Datenspeicher. Wie das Beispiel der Schallplatte aus UHPC zeigt, lassen sich Muster, die hier die Schallinformationen enthalten, exakt von einer Matrize kopieren.
Invasoren im Kleiderschrank
(2016)
In respect of modern approaches in material sciences and highly increased requirements on materials on safety relevant components, quality management and non-destructive testing reclaims a steadily increased meaning. The destructive meaning of measuring the degree of purity is defined in DIN EN 10247 through metallurgical investigations, especially microsections. For and comparable, but non-destructive testing due ultrasonic testing, the material the SEP 1927 is a well-defined industry standard. A novel and alternative way of reference block construction was focused by this work. The proposed amendments, regarding the manufactoring and machining, are less time and cost consuming. Verified by measurements the presented reference block fits the same acoustical characteristics and the requirements of the guideline.
Volatile organic compounds (VOC) are ubiquitous in the indoor air, since they emit from materials used indoors. Investigations of these materials are mostly carried out in test chambers under controlled climatic conditions. Quality control of these test chamber measurements is important but there is a lack of commercially available homogenous reference materials. The approach of this study is to dope a supporting material with VOCs, which are then reproducibly released in measurable chamber air concentrations between 30 to 300 µg m ³. From several tested supporting materials vacuum grease (APIEZON M) was selected because of its very low own emissions. First tests were conducted with styrene. For the estimation of the initial emission and the emission over time FEM (finite element methods) modelling was used. Based on this, five samples with a surface of 7 cm2 and a thickness of 12 mm with a content of 1 ‰ styrene were investigated at (23 ± 2) °C and (50 ± 5) % relative humidity in the µ-chamber (3 samples) and 24 L test chambers (2 samples) for 28 days. Air samples were taken after 24 hours, 3, 7, 14, 21 and 28 days on Tenax TA® sorption tubes and analyzed by TD-GC-MS. The area specific emission rate (SERa) was calculated to compare the results from both chamber types. After 24 hours SERa was between 0.8 0.9 µg cm 2 h 1 (3800 4000 µg m 3) for the µ-chamber samples and between 0.9 1.1 µg cm 2 h 1 (300-370 µg m 3) for the 24 L test chamber samples. After 28 days the SERa was at 0.2 µg cm 2 h 1 for all samples. The relative standard deviation of the SERa was between 1 26 %. These results show the applicability of vacuum grease as supporting material and the favored starting concentration range could be achieved in the 24 L test chambers.
In situ investigations using PXRD coupled with Raman spectroscopy permit the evaluation of the formation pathways of milling reactions. The liquid-assisted grinding cocrystallisation of theophylline with benzamide leading to polymorphic compounds was investigated. The dipole moment of the solvent used in the synthesis determines the structure of the polymorphic product. A detailed investigation allows determining the kinetically and thermodynamically favored product. In situ observations of the formation pathway during the grinding process of both polymorphs show that the thermodynamically favored cocrystal is formed in a two-step mechanism with the kinetic cocrystal as intermediate. The evaluation of the mechanochemical formation pathways reveals the importance of in situ investigations for an in depth understanding of mechanochemical synthesis mechanisms. Our study demonstrates that the choice of the solvent in the LAG synthesis is decisive for the controlled formation of a desired polymorphic final product.
Das EU-Projekt HOMER befasst sich mit den sogenannten Home Made Explosives (HMEs) und frei verfügbaren Rezepten für deren Herstellung. Diese Selbstlaborate spielen in der heutigen Zeit vor allem im Zusammenhang mit terroristischen Aktivitäten eine bedeutende Rolle. Informationen zu HMEs und ihrer Herstellung werden einfacher denn je über das Internet verbreitet. Hier knüpft das im 7. EU‑Forschungsrahmenprogramm finanzierte Projekt an und bezweckt, die im Internet verfügbaren Quellen auszuwerten und so die Informationslage für Sicherheitskräfte und Ermittlungsbehörden zu verbessern. Im Rahmen des Projektes wird eine automatisierte Suche von Rezepten im Internet entwickelt. Die gefundenen sowie die im Projekt generierten Informationen über HMEs sollen im Endergebnis in Form einer Software (Knowledge Management Platform) informationstechnisch nutzbar gemacht werden. Diese Datenbank soll auch für mobile Geräte zur Verfügung stehen. Der Schwerpunkt der Projektbeteiligung des Fachbereichs 2.3 Explosivstoffe der BAM liegt in der Bewertung der Rezepturen und der auf ihrer Grundlage hergestellten Laborate. Es wurden HMEs entsprechend der vorgefundenen Rezepte und unter Beachtung aller notwendigen Sicherheitsvorkehrungen hergestellt und anschließend sicherheitstechnisch geprüft und bewertet. Dabei wurden sowohl Handhabungsparameter wie die Empfindlichkeiten gegen Schlag, Reibung und thermische Einflüsse ermittelt, als auch die Leistungsparameter wie Detonationsgeschwindigkeit und Luftstoßdruckwirkung gemessen. Die gewonnen Erkenntnisse fließen in die genannte Datenbank ein und sollen beispielsweise Einsatzkräften vor Ort helfen, angemessene Schutzabstände zu ermitteln. Auch das Personal in Laboren der Kriminalämter profitiert von der zusammengetragenen Information über HMEs bei der Analyse von unbekannten Explosivstoffspuren.
X-ray powder diffraction (XRD) patterns of the high-temperature (HT) cristobalite form of SiO2 and its isoelectronic AlPO4 analogue are essentially influenced by the dynamic disorder of these crystal structures. The nature of this disorder and of the phase transition between the α- and β-form has been the subject of intensive research during the last four decades [1]. By 1989 it became possible to stabilize the HT-form of cristobalite SiO2 at room temperature in laboratory and engineering ceramic industries by applying solid solution forming techniques [2]. However, for the HT-form of cristobalite AlPO4 nothing similar has been known until 2014 when it was discovered that nanocrystalline and stacking-disordered β-cristobalite AlPO4 is the major component of the fly ash of a large incineration facility operated by the waste water treatment authorities of Frankfurt/M. [3]. Previous comprehensive investigations of this fly ash failed to interpret its complex XRD pattern – presumably mainly due to the lack of a matching experimental digital pattern in the Powder Diffraction Database. The present paper reports on a synthesis route that facilitates the crystallization of nanocrystalline and stacking-disordered β-cristobalite AlPO4 that is free of crystalline impurity phases and long-term stable at ambient. Its room temperature XRD pattern is presented with parameters traced back to certified reference materials.
[1] Yuan F. and Huang L., Phys. Rev, B, 2012, 85, 134114. [2] Perrotta J.A., Grubbs D.K., Martin E.S., Dando N.R., McKinstry H.A. and Huang C.-Y., J. Am. Ceram. Soc., 1989, 72, 441. [3] Peplinski B., Adam C., Adamczyk B., Müller R., Michaelis M., Krahl Th. and Emmerling F., Powder Diffraction Journal, 2015, 30, 2, Supp. 1, S31.
Characterization of silver nanoparticles in cell culture medium containing fetal bovine serum
(2016)
Nanoparticles are being increasingly used in consumer products worldwide, and their toxicological effects are currently being intensely debated. In vitro tests play a significant role in nanoparticle risk assessment, but reliable particle characterization in the cell culture medium with added fetal bovine serum (CCM) used in these tests is not available. As a step toward filling this gap, we report on silver ion release by silver nanoparticles, and changes in the particle radii and in their protein corona when incubated in CCM. Particles of a certified reference material (CRM), p1, and particles of a commercial silver nanoparticle material, p2, were investigated. The colloidal stability of p1 is provided by the surfactants polyethylene glycole-25 glyceryl trioleate and polyethylene glycole-20 sorbitan monolaurate, whereas p2 is stabilized by polyvinylpyrrolidone (PVP). Dialysis of p1 and p2 reveal that their silver ion release rates in CCM are much larger than in water. Particle characterization was performed with asymmetrical flow field-flow fractionation (FFF), small-angle X-ray scattering (SAXS), dynamic light scattering (DLS) and electron microscopy. p1 and p2 have similar hydrodynamic radii of 15 nm and 16 nm, respectively. The silver core radii are 9.2 and 10.2 nm. Gel electrophoresis and subsequent peptide identification reveal that albumin is the main corona component of p1 and p2 after incubation in CCM, which consists of Dulbeccos Modified Eagle Medium with 10% fetal bovine serum added.
Wasserstoffbarrieren aus Glas erfahren zunehmend Bedeutung als Werkstoff in der Energietechnik. Trotz wachsender Anwendungen liegen überwiegend empirisch gewonnene Beziehungen zwischen Glaszusammensetzung und Wasserstoffpermeation vor, die im wesentlichen aus dem Verhalten von Kieselglas abgeleitet werden. In dieser Studie werden daher topologische Parameter der Glasstruktur identifiziert und mit thermodynamischen Parametern korreliert. Auf der Seite der Glastopologie steht das freie Volumen und der Vernetzungsgrad des Netzwerkes während auf der thermodynamischen Seite die Konfigurationsentropie bzw. die Konfigurationswärmekapazität Aufschluss über die Verteilung des freien Volumens geben kann. Dabei wird angenommen, dass für Temperaturen weit unterhalb der Glasübergangstemperatur die chemische Löslichkeit von H2 zu vernachlässigen ist. Um die eingeschränkte Datenlage für die Wasserstoffpermeation kompositionell zu erweitern, wurden zusätzlich Heliumpermeationsmessungen ausgewertet. Die Ergebnisse zeigen, dass für Silicatgläser ein charkteristisches Verhältnis von freiem Volumen zu Netzwerkaufspaltung herrschen muss, um permeationsstabile Gläser zu erhalten.
Die Entwicklung von Wasserstoffbarrieren aus Glas erfordert die genaue Messung geringster H2-Permeabililtäten. Bisherige Untersuchungen haben gezeigt, dass die VHE-Pulvermethode diesbezüglich eine besonders hohe Empfindlichkeit bietet. Hierbei wird die isotherme Gasabgabe aus sphärischen Partikeln im Rahmen klassischer Diffusionsmodelle gefittet und daraus der Diffusionskoeffizient bestimmt. Für die Untersuchung von Gläsern mit möglichst geringer H2-Permeabilität ist jedoch eine Validierung der Genauigkeit der Methode notwendig. Vor diesem Hintergrund erfolgte die numerische Modellierung der H2-Abgabe mit Hilfe des Programms COMSOL Multiphysics®. Im Poster wird der Einfluss der Korngrößenverteilung der Glaspulverpartikel, der Partikelform sowie der Effekt einer nichthomogenen H2-Startverteilung auf die mittels Pulvermethode ermittelten Diffusionskoeffizienten diskutiert.
- einer der größten zusammenhängenden Gebäudekomplexe in Europa
- Anfang der dreißiger Jahre von Prof. Sagebiel geplant, 1936 Baubeginn, heute zu 70%fertiggestellt
- steht heute wegen großer verkehrs- und baugeschichtlicher Bedeutung unter Denkmalschutz
- in Abfertigungshalle befindliche Fachwerkträger mit selbsttätiger Vorspannung zeigen Anfang des Spannbetonbaus
- ab 1997 Überarbeitung des Nutzungskonzeptes der Räume über den Fachwerkträgern durch Berliner Flughafengesellschaft
- Erfordernis der Abschätzung der Tragfähigkeit der Fachwerkträger
Advanced methods for 3D green density characterization like computed tomography and 3D FE sinter modeling can be utilized for increasing the reliability of sintered components. The experimental in situ observation of sin-tering, however, is currently restricted to silhouette methods, i.e. heating microscopy. For complex shaped sam-ples, in situ shape screening during shrinkage would allow better validation of 3D sinter simulation models. Further, by revealing temporary sinter warpage, 3D high-temperature shape screening would allow to locate potential defects of complex sintered components. Against this background, BAM developed a testing device for in situ 3D high-temperature shape screening for ceramic and glass-ceramic tapes up to 1000°C [1-3]. Current work is focused on dropping this restriction in sample shape and temperature. The poster illustrates the current state of this work and possible applications of the method e.g. in detecting sinter warpage of metallized glass-ceramic LTCC tapes.
Um den Abbau primärer Rohstoffe zu reduzieren, wurden deponierte oder niederwertig eingesetzte industrielle Reststoffe hinsichtlich einer höherwertigen Verwendung im Betonbau untersucht. Zur Bewertung des Einsatzpotentials als Zementbestandteil oder Betonzusatzstoff erfolgte zunächst eine chemisch-mineralogische und betontechnologische Charakterisierung der Materialien. Reststoffe, die die normativen Anforderungen hinsichtlich der Zementzusammensetzung erfüllen, wurden anschließend zu verschiedenen Anteilen als Zementsubstitut in Mörtel eingesetzt. In vergleichenden Untersuchungen erfolgte die Ermittlung der Frisch- und Festmörteleigenschaften.
Kalorimetrische Untersuchungen sollten die Auswirkungen der Reststoffe auf die Zementhydratation zeigen. Ausgewählte Untersuchungsergebnisse an Reststoffen aus der Industrieabwasseraufbereitung, dem Altpapierrecycling, der Biomasseverbrennung und der Metallurgie werden vorgestellt.
Kiefernholz wird durch Imprägnieren mit einem Vorkondensat aus organischen Disäuren und Glycerin, das kolloidale Kieselsäure enthält, sowie nachfolgende Ofenhärtung in Kieselsäure/Alkydharz/Holz-Verbunde umgewandelt. Diese Nanoverbunde haben eine geringere Porosität als Holz, da Teile der Holzzellen mit Harz und Kieselsäure ausgefüllt sind. Die kugelförmigen, etwa 60 nm großen (SiO1)x-Teilchen liegen in der Polymermatrix mikrophasensepariert vor. Der kolloidale Zustand der eingebrachten Polykieselsäure bleibt erhalten. Durch ihr günstiges Eigenschaftsprofil sind die Verbundmaterialien als modifizierter Holzbaustoff interessant.
Hausmüllverbrennungsasche soll aufgrund ihrer chemisch-mineralogischen Eigenschaften als Gesteinskörnung zur Herstellung von Normalbetonen eingesetzt werden. Durch Bestandteile, wie Chloride, metallisches Aluminium und Altglasfragmente, entstehen aber in kürzester Zeit beträchtliche Betonschäden. Durch zusätzliche mechanische, chemische oder thermische Aufbereitungsschritte können diese betonschädigenden Inhaltsstoffe minimiert werden. Dadurch lässt sich die Qualität der Asche soweit verbessern, dass sie gut zur Betonherstellung verwendbar ist.
In the course of miniaturizing modern technology down to the molecular scale, much remain unknown about the materials behavior and the deviations from the bulk that might arises from confinement effects. Here, a combination of nano-sized relaxation spectroscopies (Broadband dielectric spectroscopy (BDS) and Specific heat spectroscopy (SHS); employing AC nanochip calorimetry) were utilized to investigate the glassy dynamics of ultra-thin films of Poly (vinyl methyl ether) (PVME) and of blends PVME / Polystyrene (PS) 50:50 wt-%,, which are miscible in bulk (thicknesses: ca. 8 nm – 160 nm, film thickness was controlled by ellipsometry, film topography by AFM). Both methods are sensitive to different probes; where SHS senses entropy fluctuations while BDS measures dipole fluctuations. For BDS measurements, a recently developed nano-structured electrode sample arrangement is employed, where ultra-thin films are spin-coated on an ultra-flat highly conductive silicon wafer, sandwiched between a wafer with nanostructured SiO2 nano-spacers with heights between 35 nm and 70 nm. For PVME films, two thickness independent processes were observed and interpreted to be the α-processes of a bulk-like layer and a process due to an absorbed layer to the substrate. This adsorbed layer further undergoes a confinement effect that results in the localization of the segmental dynamics, which results in an Arrhenius-like temperature dependence. A detailed analysis of the dielectric strengths of both processes reveals that the thickness of the adsorbed layer decreases with increasing temperature, while that of the bulk-like layer increases. For the blend system, by measuring the dynamic Tg in dependence of the film thickness, SHS showed that the Tg of the whole film was strongly influenced by a nanometer-thick surface layer at the polymer/air interface due to a self-assembling process. The dynamic Tg obtained from the SHS measurements decreased with decreasing film thickness. On the other hand, BDS measurements showed a completely different behavior. At high temperatures, the temperature dependence of the relaxation times of the films follows that of bulk-like PS/PVME; obeying the VFT-law. With decreasing temperature, the temperature dependence deviates from the VFT to an Arrhenius law; where the apparent activation energy decreases with decreasing film thickness. This is the first example where confinement induced changes were observed by BDS for ultra-thin films. All results were analyzed in detail in a comprehensive discussion.
Successful implementation of an optical polarimetry measurement setup. Due to wall anchoring interactions HAT6 embedded in an untreated alumina membrane exhibits a radial orientation for pore sizes in between 30 nm and 80 nm. Embedded in large membranes, pore size of 180 nm, HAT6 forms the favored hexagonal columnar phase along the pore axis.
In the last years, secondary low-energy electrons (LEE) emerged as important, if not predominant, reductive pathway in ionizing damage of biomolecules. These electrons are created in copious amount as result of inelastic scattering of high energy radiation at water. Until now, all experiments the quantification of the effects of LEEs on the biomolecular damage was either performed in vacuum with LEE sources or with DNA on surfaces in humid atmosphere.
We present a new experimental setup to irradiate biomolecules with electrons under physiological conditions. In combination with monte carlo simulations this setup makes it possible to determine microdosimetric quantities for biomolecules in liquid environment under electron irradiation.
This opens up new possibilities in radiation research to access the LEE damage under well defined physiological condition, for more complex systems, such as DNA-Protein complexes and even living cells.
Time-resolved studies on the formation of maghemite nanoparticles combining fast-XANES and SAXS
(2016)
Iron oxide nanoparticles find application in different areas like sensing, magnetic storage media, and biomedicine, due to their magnetic properties and environment-friendliness.
In the present contribution, we report on the in situ investigation of an iron oxide nanoparticle synthesis by coupled X-ray absorption near-edge structure (XANES) and small-angle X-ray scattering (SAXS). The combination provides simultaneously information about the size of particles (SAXS) and on the oxidation state and the local structure of the iron atoms (XANES). The co-precipitation synthesis was exemplary studied, using a stabilization agent to decelerate the fast precipitation of the iron oxides. This allows to detect intermediates in situ. The measurements were performed using a custom-made acoustic levitator as sample holder. From the data, a mechanism was derived indicating different phases of particle Formation and oxidation state changes.
The ability to penetrate dielectric materials makes T-rays attractive to reveal discontinuities in polymer and ceramic materials. Changes of travelling time (ToF) and pulse shape due to the interactions of THz pulses with the dielectric material and its inherent discontinuities can be observed. A tomogram of the object under the test can be reconstructed from time of flight diffraction (ToFD) scans if a synthetic focusing aperture (SAFT) algorithm is applied.
Ceramic components with complex shape cannot be produced frequently by usual ceramic forming and sintering processes. Therefore, numerous joining methods were developed and introduced in industrial scale. Nowadays, multi-stage Mo-Mn-process and active brazing are preferentially used, if temperature-stable and gastight joints are required. Unfortunately, both processes involve cost-intensive thermal processes: hydrogenous atmosphere is essential for metallization in Mo-Mn-process and active brazing takes place under vacuum. Thermal processes can be drastically simplified by using Reactive Air Brazing (RAB). Joining under air atmosphere is an interesting alternative, especially to join oxide ceramic components among themselves. So far, main disadvantage of RAB is low strength of join connections.
Aim of this investigation was the development of high-strength, thermal shock resistant and gastight ceramic-ceramic joints by RAB. Therefore,
- commercial, silver and copper oxide containing RAB soldering composition was modified by addition of ceramic particles with low thermal expansion coefficients (TEC). Hence, thermal misfit between TEC of solder and ceramic components was significantly reduced.
- RAB soldering paste was replaced with newly developed RAB composite tapes, produced by ceramic “doctor blade” technology. Thereby, improved potential exist to tailor the brazing layer relating to composition, thickness and thickness uniformity.
Gastight alumina-alumina, alumina-zirconia and zirconia-zirconia joints with strongly improved strength were produced by novel composite tapes. No strength degradation of joints was observed after thermal cycling up to 700°C.
The wetting behavior of material surfaces can be controlled by surface structures. We functionalized inorganic material surfaces, such as steel, titanium alloy and silicon, to modify the wetting behavior using ultrashort laser pulses (fs- to ps-range). The laser processing was performed by scanning the laser beam across the surface of initially polished flat sample material. A combined experimental and theoretical study of the laser processing parameters (peak fluence, scan velocity, line overlap) allowed the identification of different regimes associated with characteristic surface morphologies (laser-induced periodic surface structures, grooves, micro cones, dimples, etc.). Analyses of the surface using optical as well as scanning electron microscopy allowed the identification of morphologies providing the optimum similarity to the natural skin of lizards. For mimicking skin structures of moisture-harvesting lizards towards an optimization of the surface wetting behavior, additionally, a two-step laser processing strategy was established for realizing hierarchical micro- and nanostructures. In this approach, a laser-generated regular array of small dimples was superimposed (step 2) to the micron-scaled capillaries processed before (step 1). Optical focus variation imaging measurements finally revealed the three dimensional topography of the laser processed surfaces derived from lizard skin structures. The functionality of these surfaces was analyzed in view of wetting properties.
Large area periodic surface structures were generated on steel surfaces using 30-fs laser pulses at 790 nm wavelength. Two types of steel exhibiting a different corrosion resistance were used, i.e. a plain structural steel (corrodible) and a stainless steel (resistant to corrosion). Homogeneous fields of laser-induced periodic surface structures (LIPSS) were realized utilizing laser fluences close to the ablation threshold while scanning the sample under the focused laser beam in a multi-pulse regime. The nanostructures were characterized with optical and scanning electron microscopy. For each type of steel, more than ten dentical samples were laser-processed.
These samples were subjected to microbial adhesion tests, investigating bacterial adhesion behavior on the laser structures in comparison to polished reference surfaces. Short term experiments (<24h) were carried out to determine initial biofilm development. E. coli as a typical bacterium representing pathogenic bacteria and Shewanella putrefaciens as metal corrosive bacterium were used for biofilm development analyses. Bacterial cell adhesion was determined microscopically after DAPI cell staining (DNA staining). Comparison of the coverage areas between nanostructured and polished surfaces revealed differences in cell adhesion behavior and biofilm structure.
Laser-induced periodic surface structures (LIPSS) were generated on titanium nitride (TiN) hardcoating surfaces (deposited on metallic substrates) upon irradiation with multiple linearly polarized femtosecond laser pulses in air (30 fs duration, 790 nm wavelength, 1 kHz pulse repetition rate). The conditions were optimized in a sample-scanning geometry for the processing of large surface areas (5 mm x 5 mm) covered homogeneously by nanostructures with sub-wavelength periods ranging between ~200 nm and 700 nm. For these nanostructures the coefficient of friction was characterized under reciprocating sliding condition against a ball of hardened steel at 1 Hz using different lubricants (regime of mixed friction). After 1000 cycles, the corresponding wear tracks were characterized by optical and scanning electron microscopy. High-resolution energy dispersive X-ray analyzes (EDX) allowed the visualization of chemical alterations within the wear tracks. For specific conditions, the nanostructures endured the tribological treatment. Our experiments provide a qualification of the tribological performance of the fs-LIPSS on TiN surfaces.
Laser-induced periodic surface structures (LIPSS, ripples) were generated on steel and titanium surfaces upon irradiation with multiple linear polarized femtosecond laser pulses (pulse duration 30 fs, central wavelength 790 nm). The experimental conditions (laser fluence, spatial spot overlap) were optimized in a sample-scanning geometry for the processing of large surface areas covered homogeneously by the nanostructures. The irradiated surface regions were subjected to optical microscopy (OM), white light interference microscopy (WLIM) and scanning electron microscopy (SEM) revealing sub-wavelength spatial periods. The nanostructured surfaces were tribologically tested under reciprocal sliding conditions against a sphere of hardened 100Cr6 steel at 1 Hz using paraffin oil and engine oil as lubricants. After 1000 sliding cycles at a load of 1.0 N, the corresponding wear tracks were characterized by OM and SEM. For specific conditions the laser-generated nanostructures endured the tribological treatment. Simultaneously, a significant reduction of the friction coefficient was observed in the laser-irradiated (LIPSS-covered) areas when compared to the non-irradiated surface, indicating the potential benefit of laser surface structuring for tribological applications.
For the characterization of disperse and porous solids, usually single gas adsorption(GA) is employed. In the case of liquid adsorption (LA), the extraction of information on solids immediately becomes a more sophisticated matter since information on geometric as well energetic parameters of the solids is both superposed by liquid-mixture effects and displayed in excess terms. We have to ask if reliable solid parameters can be also obtained from LA isotherms. The enlarged data bank of gas and liquid adsorption measurements enables us to change systematically solid parameters (e.g., the pore width of MCM-41, the pore entrances of SBA-16, chemical heterogeneity) and to study in this way the influence of solid parameters on LA.
Ionic Liquids (ILs) are employed in various fields, for example, reaction engineering (reactions with gases, such as hydroformylation (CO, H2), hydrogenation (H2), oxidation (O2)) or separation technology (separations of gases, reactants, and high-volatility reaction products). For the basic engineering of such processes, knowledge of phase equilibria, particularly of mixtures, over a broad (p,T) range is mandatory. This contribution reports on recent experimental results from our laboratory: – for the simultaneous solubility of a binary gas mixture in a pure ionic liquid – for the solubility of a single gas in a binary liquid solvent mixture.
The term „Alternative Solvents“ often refers to ionic liquids (ILs), mainly to distinguish these substances from traditional (i.e., molecular) solvents.
In applications, any „alternative“ is required to perform better than something that is proven and tested.
To bring ILs into practical use, availability and costs are the fundamental points to be addressed.
There are two ways to proceed:
▬ tailoring a molecule, implanting the expected characteristics
advantage: optimization of the targeted performance possible
risks: outcome not always foreseeable, costly and time-intensive (“trial and error“)
▬ to target on mixtures of well-characterized ILs with molecular solvents
advantage: substance characteristics are known, less costly, less time-consuming,
mixture composition another tunable parameter
risks: the same but with less impact
For the basic engineering of technical processes, knowledge of phase equilibria, particularly of
mixtures, over a broad (p,T) range is mandatory.
This contribution reports on recent experimental results from our laboratory:
▬ the solubility of CO2 in a mixture of water and [bmim][CH3SO4]
▬ the solubility of CO2 in a mixture of methanol and [bmim][PF6]
While polymorphism is a common phenomenon in the crystallization processes of organic compounds, polyamorphism has gained importance only recently. Using sophisticated sample environments and applying in situ scattering methods and vibrational spectroscopy, the complete crystallization process of organic compounds from solution can be traced and characterized. Diffuse scattering from amorphous intermediates can be investigated by analyzing the atomic pair Distribution function (PDF) to gain further insights into molecular pre-orientation. The crystallization behavior of Paracetamol was studied exemplarily under defined, surface-free conditions. Based on the choice of the solvent, the formation of different polymorphs is promoted. The thermodynamically stable form I and the metastable orthorhombic form II could be isolated in pure form directly from solution. For both polymorphs, the crystallization from solution proceeds via a distinct amorphous precursor phase. PDF analyses of these different amorphous states indicate a specific pre-orientation of the analyte molecules introduced by the solvent. The resulting crystalline polymorph is already imprinted in these proto-crystalline precursors. Direct experimental evidence for the polyamorphism of paracetamol is provided.
One-part-geopolymers, produced by addition of water to a mixture of solid silica and sodium alumi-nate, are a less exhaustively studied approach to form geopolymeric binders. Depending on the silica source, the reaction products show significant amounts of zeolite Na-A besides amorphous compounds. Previously, 29Si MAS NMR has been used to analyze the chemical structure of such one-part geopolymers, having crystalline structures and amorphous phases (Q2, Q3, Q4).
In this work, pure zeolites and three different one-part-geopolymers cured for 1 day were investigated by 29Si-27Al TRAPDOR NMR. It was used to identify aluminum phases in overlapping silicon sites. Zeolites Na-X (Si/Al=1.4) and Na-Y (Si/Al=2.7) served as model systems to measure the TRAPDOR effect of the structural units Q4(mAl). Both materials show several Q4(mAl) signals, which are all separated by their chemical shifts. The more aluminum surrounds the silicon tetrahedron the higher are the normalized TRAPDOR difference signals (S0/∆S). The intensity ratios between Q4(mAl) to Q4({m-1}Al) of these signals is fixed but vary slightly between both zeolites. These results are transferred to the complex geopolymer structure.
Mechanochemistry is increasingly used for synthesizing various materials including cocrystals and metal organic compounds. Although this synthesis approach offers a fast and pure synthesis in high yields there is a lack in understanding the mechanisms of milling reactions. The driving forces triggering the formation of cocrystals under milling conditions were investigated using a set of multi-component competitive milling reactions. In these reactions, different active pharmaceutical ingredients were ground together with a further compound acting as coformer. The study was based on new cocrystals including the coformer anthranilic acid. The results of the competitive milling reactions indicate that the formation of cocrystals driven by intermolecular recognition are influenced and inhibited by kinetic aspects including the formation of intermediates and the stability of the reactants.
Ultrasonic echo testing has become a common method in civil engineering for the investigation of concrete structures. The detection of inhomogeneities, reinforcing elements and the geometry of the object is required for quality assurance and Inspection. This assessment depends on the quality of ultrasonic images which can be improved by using Reverse Time Migration (RTM) rather than the standard method, Synthetic Aperture Focusing Technique (SAFT). Although RTM provides a better mapping of circular objects and (dipping) reflectors, the image is corrupted by migration noise. To suppress the image noise, we have tested various filter methods in the spatial domain, frequency domain as well as in the curvelet domain on ultrasonic RTM images. We found that either a spatial edge detection filter in combination with a lowpass filter (Laplacian of Gaussian filter) or two lowpass filter with different filter parameters (Difference of Gaussian filter) removed artefacts. An additional smoothing was obtained by applying the first generation curvelet transform after downsampling the image matrix and adding Gaussian noise. The proposed filter scheme is able to suppress RTM noise and enhance the image quality such that the objective interpretation of ultrasonic images for Quality assessment of concrete specimen is simplified.
One of the alternative renewable fuels is biomass but it is a difficult fuel because of its diversity and complexity. It can contain high percentages of K and Cl responsible for corrosion together with sand that have additionally an abrasive effect during combustion. Because of permanently extending the surface reaction due to abrasion the corrosion of the materials increases. In particular in power plants, the superheater tubes are exposed to a corrosive abrasive attack that is one of the main sources of concern. The development of new alloys for multilayer surface, which combines corrosive and abrasive resistance is therefore of high importance. Those new technical approaches must be at the same time cost-effective to be an alternative to conventional materials. The aim of the presented investigation methods is to test and develop suitable alloys for coatings for the super heater tubes of biomass power plants. First results of abrasion investigations show improved abrasion resistance compared to the multi-component reference material Alloy 625.
The integration of finite element method (FEM) into the least-squares adjustment presented in is further extended for a joint evaluation of an elastostatic model and displacement field measurement. For linear solids which obey the Hooke's law, the material parameters determination from measurements is being examined.
Hard materials consist of a hard phase embedded in a metallic binder. In order to achieve high toughness and strength, it is necessary to have a perfect mixing of hard phase and binder, which is mainly achieved by ball milling. Niobium carbide (NbC) has a high potential to substitute tungsten carbide as hard material.
The publication presents the development of stable homogeneous and de-agglomerated NbC-dispersions. To prevent agglomeration of the powder, stable suspensions were achieved by surface treatments with the dispersants (PD and HD), which resulted in a charge reversal from a negative to a positive zeta potential. This surface-modified powder guaranteed a stable re-dispersion in the binder suspension. Nickel powder was added as metallic binder. This suspension was suited for 3D-printing. The green samples could be sintered in vacuum or Argon atmosphere.
Microbial induced corrosion (MIC) is a crucial problem in many technical plants as well as fuel tanks, leading to considerable damage and huge financial losses. Successful prevention of MIC requires the localization of first signs of corrosion as well as the identification of factors influencing the corrosion process. In this respect, also the determination of corrosion rates can be of interest for the possible prevention of MIC. Hence, there is a growing need for sensitive and preferably inexpensive tools that enable the early detection of MIC. Of special interest are methods, which provide spatially and time-resolved information and allow the study of changes on metal surfaces as prerequisites for a more detailed analysis of ongoing corrosion processes at a MIC-affected site.
Biofilm formation can lead to changes in pH, oxygen and chloride concentration as well as to the release of certain metal ions like Fe(II) and Mn(II) depending on the type of metal surface involved. Hence, optical methods enabling the detection of these analytes at very low concentration and monitoring of their changes can be used for MIC detection. Here, we propose to utilize polymeric nanosensors for MIC detection via the determination of the local pH value changes in different biofilms. Such nanosensors are known to have several advantages in imaging applications such as intracellular pH measurements including the ease of doping or labeling with a multitude of analyte-responsive and inert dye molecules for the realization of a high analyte sensitivity and ratiometric sensing. Moreover, they can be surface functionalized with target-specific ligands e.g., lectins, for the specific binding to the outer surface of certain types of bacteria. In this respect, different polymer architectures will be studied to identify an optimal candidate in terms of imaging performance in conjunction with several classes of pH-responsive fluorescent dyes like cyanines, aza-BODIPYs, and xanthenes, utilizing different mechanism of signal generation such as photo-induced electron transfer or protonation-induced changes in the spectral position of absorption and emission spectra.
Current pollen screening information networks are based on time-consuming, microscopic determination of the genus-specific pollen morphology. Additionally, the given information relies on prediction of plant growth, wind direction and seasonal information.
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was introduced for rapid analysis of complex biological samples. MALDI-TOF provides the possibility to measure species-specific mass peak patterns of pollen and offers a powerful tool for investigation of taxonomic relations.
Our objective is to develop a fast, reliable, routine method for detecting single pollen grains in pollen mixtures. The obtained spectra are analyzed by multivariate statistics.
The controlled production of supramolecular aggregates formed by the self-assembly of dendritic amphiphiles is of great interest owing to their potential application in the fields of nanotechnology and nanomedicine. Dendritic amphiphiles as building blocks offer the advantage that their structure and size can be precisely tuned through organic synthesis. This synthetic flexibility enables the fine-tuning of the hydrophobic to hydrophilic ratio of the dendritic segments, which mainly controls the morphology of the self-assembled structures.
A promising method for the controlled preparation of supramolecular assemblies is based on the use of micromixers.[5,6] Due to their mixing times in the range of milliseconds at the microscale level, the application of such microfluidic systems benefits from a high mixing efficiency, a low mixing time and a reproducible synthesis compared to conventional batch-based techniques such as the solvent injection method or the film hydration method.
Herein, we report on the microfluidic-assisted self-assembly of several dendritic amphiphiles and the impact of the mixing parameters on the self-assembly process.
The use of high-performance concretes holds great promise for many structural applications. This paper investigates the performance of these materials when used in combination with traditional reinforcing bars. An improved understanding of failure during reinforcing bar pull-out from high-performance concretes is needed in order to better predict the embedment length required to develop full reinforcing bar pull-out strength and the required thickness of reinforcing bar cover for adequate corrosion protection. The cracking structures surrounding the reinforcing bars were analyzed using x-ray computed tomography (CT) in order to determine the stress states causing failure. This was accomplished by conducting in-situ reinforcing bar pull-out experiments during CT scanning. A conventional concrete, a high-strength concrete, and a high-strength fiber reinforced concrete were all tested during the experiments. The results of these experiments showed that the levels of brittleness of the different concrete materials had a major impact on the failure mechanisms that they experienced during reinforcing bar pull-out. It was also clear that the specimen geometry and the casting method had a major impact on fiber orientation. The inclusion of fibers within concrete was also found to significantly improve strength and corrosion protection during reinforcing bar pull-out.
High resolution in situ monitoring of the initial cement hydration influenced by organic admixtures
(2015)
Numerous admixtures are used in the building practice to customize the properties of the cement paste during application. The influences of admixtures on the course of cement hydration and formation of hydrate phases have to be considered. Polycarboxylate ether (PCE) based polymeric superplasticizers (SPs) are known to retard the setting of the cement paste. The extent of the retardation differs depending on the molecular structure of the SP. Additionally, the presence of a stabilizing agent (SA) in the cement paste has a retarding side effect on the setting. The initial cement hydration processes and the detailed mechanisms of the retardation influenced by PCEs, as well as their interactions with particular SAs, are insufficiently understood. Up to now, only the results of phenomenological studies were taken into account to describe this retardation process. A detailed structure analysis monitoring the change of the phase composition during the hydration was never applied. Both SP and SA affect the adsorption of the sulphate ions on the clinker particles, causing changes in the formation of ettringite during the initial hydration, and are therefore a crucial part of the setting process itself. Here, the initial hydration of cement influenced by the interaction of SP and SA was monitored in situ by synchrotron X-ray diffraction. The high time resolution of the measurements allowed a continuous detection of the hydrates formed. The hydration was followed from the starting point of water addition and for couple of hours afterwards. The hydration of the levitated cement pellets containing starch as SA was initialized by adding aqueous solutions of different commercial SPs. Changes in the ettringite formation were detected in comparison to the reference hydration of pure cement.
Zur Planung und Durchführung umfangreicher Sanierungs- und Umbaumaßnahmen im Pergamon-Museum Berlin bestand die Erfordernis einer Bauzustandsanalyse an antiken Baudenkmälern. Bestandsunterlagen waren unvollständig vorhanden bzw. fehlten. Hieraus ergab sich die Notwendigkeit des kombinierten Einsatzes zerstörungsfreier
Prüftechnik.
Ultra High Performance Concrete (UHPC) is characterized by high strength and high durability. This is achieved by an optimized grain size distribution, especially within fine grains, and addition of superplasticizer, which allow the reduction of the water/cement ratio in the cement paste and thereby the increase of the density of UHPC. Thermal treatment, i.e. curing at elevated temperature and pressure, contributes to a further increase of compressive strength. The aim of the presented study was to analyze the effect of thermal treatment at 90 ◦C and atmospheric pressure on UHPC samples. Varying factors were the age of the samples when heat treatment started (initial storage time), the duration of heat treatment and the type of heat treatment. It was applied in three ways: 1. treated without any protection, 2. sealed in plastic foil and 3. treated in hot water. Afterwards the samples were analyzed with respect to their mechanical properties and their phase composition. Furthermore, the weight (water absorption) of the samples was observed over 28 days and was correlated with the strength test results. The development of strength depends on the combination of initial storage time and the duration of heat treatment and is also influenced by the type of thermal treatment. The highest compressive strengths have been observed by implementing the hot water treatment. Thereby the weight of the samples increase due to additional absorbed water. This enables an increased hydration of cement clinker inducing a higher strength.
Lightweight granules are mineral, spherical and porous particles with bulk density less than 2000 kg m . New types of lightweight granules are made from masonry -3 rubble as an alternative to the commonly used expanded clay and shale. They are produced in a multistage manufacturing process by thermal or hydrothermal treatment. Studies of the microstructure of the new lightweight granules are very important to optimise the engineering properties with regard to different applications from lightweight concrete to planting substrates and wastewater treatment. Here, the results of porosity and pore structure measurements are presented. Characteristic samples with different bulk densities of both thermally and hydrothermally hardened granules have been analysed by means of various methods.
Leichte Gesteinskörnungen mit Kornrohdichten < 2 g/cm³ werden industriell aus natürlichen Rohstoffen, wie Ton und Schiefer, hergestellt. Dabei fallen hohe Energiekosten an, während außerdem fortwährend die Verfügbarkeit geeigneter Rohstoffe sinkt. Eine Alternative stellen Leichtgranulate, die aus mineralischen Bau- und Abbruchabfällen hergestellt werden, dar.
Im Forschungsprojekt „Aufbaukörnungen“ wurde eine Technologie zur Herstellung hochwertiger leichter Gesteinskörnungen aus Mauerwerkbruch entwickelt. Ziegelhaltige Bau- und Abbruchabfälle fallen in Deutschland mit bis zu 26 Mio. t pro Jahr an und weisen größere Verwertungsdefizite als Betonbruch auf. Der neuen Verwertungsstrategie liegt die Idee des rohstofflichen Recyclings zu Grunde.
Die leichten Gesteinskörnungen werden am Ende eines mehrstufigen Herstellungsprozesses durch thermische oder hydrothermale Erhärtung im Labor- und halbtechnischen Maßstab produziert. Für Herstellungstechnologie und Eigenschaften der Leichtbetone sind neben Kornfestigkeit und Rohdichte die Porosität und Wasseraufnahme der leichten Gesteinskörnungen entscheidende Größen, die wiederum von Kornform, Oberflächenrauigkeit, Sinterschale und Porenstruktur der Körnungen beeinflusst werden.
- jährlicher Anfall von 5.000 bzw. 10.000 Tonnen
wasserhaltiger Filterrückstände (FR) pro Produzent bei
der Abwasser-Neutralisation aus der Kieselsäure- bzw.
Chlorsilanherstellung (FR1, FR2)
- heute: Deponierung, Tagebauverfüllung
- ungenutzte Sekundärrohstoffquelle
- Untersuchung möglicher Anwendungsbereiche für FR
- 5.000 bis 10.000 t wasserhaltiger Filterrückstand (FR) entstehen jährlich pro Produzent bei der Neutralisation der Abwässer aus der Silicon- oder Kieselsäureherstellung
- Anfall als fester, feuchter, schollenartiger Filterkuchen
- Verwertung heute: Deponierung, Tagebauverfüllung -> ungenutzte Sekundärrohstoffquelle
- Untersuchung der Einsatzmöglichkeiten der aufbereiteten Filterrückstände zur Eigenschaftsverbesserung
zementgebundener Baustoffe analog der wohlbekannten Anwendung von hochdisperser Kieselsäure und Silicastaub
Worldwide, cement and concrete experts are at the cutting-edge to sustainable, green, healthy but nonetheless high-Performance concrete. The current relatively low development of the cement and concrete industry in Africa offers the unique opportunity to start directly on the best achievable and sustainable Level, if only Expertise is sufficiently available. It should not be neglected that concrete is a product with comparably low Transport ranges, which means that an improved concrete market will mainly Support the local economy without exceeding financial Drains to the international market, thus fostering the fight against poverty, which is an urgent Need in most African countries.
Untersucht wird die Entwicklung einer Technologie zur Herstellung hochwertiger Leichtgranulate (Blähgranulate) mit definierten Produkteigenschaften aus heterogenen Bau- und Abbruchabfällen, Anwendung der Granulate als leichte Gesteinskörnung im Beton und die Möglichkeit des rohstofflichen Recyclings mineralischer Bauabfälle
- Zunehmender Energiebedarf erfordert höhere Übertragungskapazitäten
- Dezentrale ökologische Energiegewinnung, z. B. Offshore, erfordert Übertragung großer Energiemengen in die Ballungszentren (Nord-Süd-Trassen)
- Hohe Auslastung der Netze erfordert Beherrschbarkeit der im Fehlerfall auftretenden Risiken für Menschen, Umwelt und energietechnische Anlagen
- Etwa 90 % der Anlagenausfälle sind verursacht durch Teilentladungen (TE) in Endverschlüssen und Muffen mit modernen polymeren Isoliersystemen
- Etablierte elektrische Verfahren erlauben nur externe Schadensdetektion.
Die Fixierung der Stahlanker im Felsfundament zur Stabilisierung der Schwergewichtsmauer werden mit integrierten faseroptischen Dehnungssensoren überwacht.
In die Glasfaser sind Reflektoren eingebaut; zwei Reflektoren bilden jeweils eine Messstrecke, die Auskunft über die Fixierung geben. Am Ankerkopf wird der Zustand der Messstrecken abgefragt.
Im Hinblick auf eine nachhaltige Entwicklung sollen nach dem KrW/AbfG der Rohstoffeintrag und der Abfallaustrag in den Lebensphasen eines Bauwerks durch weitgehende Verwertung von Sekundärrohstoffen (Reststoffen) möglichst gering gehalten werden. Ein Einsatz von Reststoffen wie Hausmüllverbrennungsaschen (MV-Aschen) im Betonbau kann potenziell einen wesentlichen Beitrag zur nachhaltigen
Entwicklung leisten.
Untersucht wurde der Einfluss der Applikationsart (konventionelle und gespritzte Herstellung, Wasserlagerung bis zur Prüfung), der Einfluss von Fasern (konventionelle Herstellung, Wasserlagerung bis zur Prüfung) und der Einfluss von Schwindreduzierern (konventionelle Herstellung, Luftlagerung bis zur Prüfung).
Modern CO2-reduced power plants with Oxyfuel-Combustion operate with gas compositions of high CO2 partial pressure and steam (Boiler, Recycling). The corrosion process occurring under such service conditions is different from that under current conditions with air combustion. The effect of temperature, pressure, chromium content on the corrosion reaction of typical power plant steels in CO2 -H2O and CO-H2O-O2 was investigated.
Beim bispektralen Verfahrensprinzip (auch 2-Monochromatoren-Methode genannt) zur Charakterisierung fluoreszierender Reflexionsproben wird das Probenmaterial monochromatisch bestrahlt und für jede dieser anregenden Wellenlängen das emittierte Spektrum monochromatisch gemessen. Dies hat gegenüber einer polychromatischen Anregung (z. B. Normlichtart D65) den Vorteil, dass spektrale Materialfunktionen (Gesamt-, Reflexions- und Lumineszenz-Strahldichtefaktoren sowie das Lumineszenz-Anregungsspektrum) und diverse Farbmaßzahlen (Sicherheits- und Kontrastfarben; Referenzmaterial) für beliebige Anregungsspektren (Normlichtarten) bestimmt werden können.
Im Hinblick auf eine nachhaltige Entwicklung sollen nach dem KrW/AbfG der Rohstoffeintrag und der Abfallaustrag in den Lebensphasen eines Bauwerks durch weitgehende Verwertung von Sekundärrohstoffen (Reststoffen) möglichst gering gehalten werden. Ein Einsatz von Reststoffen wie Hausmüllverbrennungsaschen (MV-Aschen) im Betonbau kann potenziell einen wesentlichen Beitrag zur nachhaltigen Entwicklung leisten.