Chemische Charakterisierung und Spurenanalytik
Filtern
Erscheinungsjahr
- 2019 (208) (entfernen)
Dokumenttyp
- Vortrag (98)
- Zeitschriftenartikel (67)
- Posterpräsentation (36)
- Beitrag zu einem Tagungsband (2)
- Dissertation (2)
- Buchkapitel (1)
- Sonstiges (1)
- Forschungsbericht (1)
Sprache
- Englisch (161)
- Deutsch (45)
- Mehrsprachig (2)
Schlagworte
- ICP-MS (13)
- Mikroplastik (13)
- Process Analytical Technology (12)
- Isotope analysis (9)
- LIBS (9)
- Laser ablation (9)
- Online NMR Spectroscopy (9)
- CONSENS (8)
- Digitalisierung (8)
- HR-CS-MAS (8)
- Nanoparticle (8)
- Magnesium (7)
- Mass spectrometry (7)
- Optical spectroscopy (7)
- Prozessindustrie (7)
- Reaction Monitoring (7)
- Cell (6)
- Synchrotron (6)
- TED-GC-MS (6)
- LA-ICP-MS (5)
- Microplastics (5)
- Prozessanalytik (5)
- XRF (5)
- qNMR (5)
- Analytik (4)
- Automation (4)
- Data Analysis (4)
- Datenanalyse (4)
- Electrochemistry (4)
- Imaging (4)
- Plasma modeling (4)
- Process Industry (4)
- Smarte Sensoren (4)
- Comparability (3)
- Delta value (3)
- Effect based Method (3)
- Estrogens (3)
- Fluorescence (3)
- GDMS (3)
- ISO-Guide 35 (3)
- Industrie 4.0 (3)
- Interlaboratory Comparison (3)
- MC-ICP-MS (3)
- MS based method (3)
- Mass-Spectrometry (3)
- Mechanochemistry (3)
- Modular Production (3)
- Mycotoxins (3)
- Online NMR spectroscopy (3)
- Online-NMR-Spektroskopie (3)
- Peptide library (3)
- Plasma (3)
- Process analytical technology (3)
- Reliable measurements (3)
- Single cell-ICP-ToF-MS (3)
- Transformationsprodukte (3)
- XRD (3)
- Absolute isotope ratio (2)
- Accurate mass (2)
- Acoustic levitation (2)
- Analysis (2)
- Array (2)
- Asymmetrical flow field flow fractionation (AF4) (2)
- BFR (2)
- BODIPY (2)
- Benchtop NMR (2)
- Benz[a]anthracene (BaA) (2)
- Benzo[a]pyrene (BaP) (2)
- Bioconjugation (2)
- Boron (2)
- CCQM (2)
- CRM (2)
- Calibration (2)
- Capillary electrophoresis (CE) (2)
- Compact NMR Spectroscopy (2)
- Compound annotation (2)
- Datenvorbehandlung (2)
- Diatomic molecule (2)
- Diatoms (2)
- Digitization (2)
- Electrospray ionization (2)
- Ergot (2)
- Extrahierbar organisch gebundenes Fluor (EOF) (2)
- Fatty acid metabolism (2)
- Fluorine (2)
- GC-MS (2)
- Gadolinium (2)
- Gas chromatography (GC) (2)
- HR-CS-GFMAS (2)
- Halogene (2)
- Hapten Immunoassay (2)
- High-resolution MS (2)
- Isotope dilution (2)
- Isotope dilution (ID) (2)
- Laser induced plasma (2)
- Lipidomic profile (2)
- Liquid chromatography (LC) (2)
- Low-field NMR spectroscopy (2)
- MOSES (2)
- Mass spectrometry (MS) (2)
- Metabolic stress (2)
- Molecularly imprinted polymers (2)
- Multicellular spheroid (2)
- NMR Spectroscopy (2)
- Nanoparticles (2)
- Nontarget analysis (2)
- Oberflächengewässer (2)
- Polycyclic aromatic hydrocarbon (PAH) (2)
- Polymer (2)
- Probenahme (2)
- Proteins (2)
- Provenance (2)
- Prozesskontrolle (2)
- Quantitative NMR Spectroscopy (2)
- RFA (2)
- Reference materials (2)
- Referenzmaterialien (2)
- Ringversuch (2)
- SHS (2)
- SI traceability (2)
- Sampling (2)
- Sampling techniques (2)
- Schadstoffe (2)
- Speciation analysis (2)
- Standardization (2)
- Standarisierung (2)
- Sulfur (2)
- Transformation product (2)
- Tumor metabolism (2)
- Warfarin (2)
- Wastewater (2)
- Water (2)
- XANES (2)
- ZRM (2)
- Absolute fluorometry (1)
- Aflatoxins (1)
- Africa (1)
- Altenuene (1)
- Alternaria mycotoxins (1)
- Aluminium (1)
- Ambient pressure laser ionization (1)
- Analyseverfahren (1)
- Analytical Sciences (1)
- Analytical methods (1)
- Analytics (1)
- Antifouling biocides (1)
- Antifouling-Biozide (1)
- Antikörper (1)
- Applied optical spectroscopy (1)
- Archean ocean (1)
- Artificial intelligence (1)
- Aufbereitung (1)
- Automated single cell-ICP-ToF-MS (1)
- Automated system (1)
- Autophagy (1)
- BAMline (1)
- BERM (1)
- Battery (1)
- Bead injection spectroscopy (1)
- Beamline (1)
- Bias (1)
- Binder (1)
- Biochip (1)
- Biogenic carbonates (1)
- Bioimaging (1)
- Biosilicification (1)
- Bone matrix (1)
- Boron isotope (1)
- Borosilicate glass (1)
- Böden (1)
- CE-ICP-MS (1)
- CF LIBS algorithms (1)
- CXC (1)
- Calcification (1)
- Calibration-free LIBS (1)
- Cancer (1)
- Cancer cells (1)
- Capillary electrophoresis (1)
- Capillary electrophoresis-mass spectrometry (1)
- Carrier gas hot extraction (1)
- Catalysis (1)
- Central Taurus (1)
- Chemical coverage (1)
- Chemical reactors (1)
- Chemometric (1)
- Chemometrics (1)
- Chemometry (1)
- Chlorine (1)
- Clones (1)
- Cluster (1)
- Cobalt deposition (1)
- Cocaine (1)
- Cocrystals (1)
- Color X-ray Camera (1)
- Combinatorial screening (1)
- Compact NMR spectroscopy (1)
- Competitive Immunoassay (1)
- Complementary MS (1)
- Construction Products (1)
- Continuous processes (1)
- Copper (1)
- Corrosion (1)
- Crude oil (1)
- Cultural heritage (1)
- Data Fusion (1)
- Datenauswertung (1)
- Dead Sea Scrolls (1)
- Debromination (1)
- Deep work (1)
- Delta values (1)
- Depht profiling (1)
- Detektion (1)
- Diatom (1)
- Diatomeenanalytik (1)
- Diatomic (1)
- Digitale Transformation (1)
- Digitaler Zwilling (1)
- Dissolution (1)
- Dried fig (1)
- EC/MS (1)
- EDX Analysis (1)
- ELISA (1)
- ESEM (1)
- EXAFS (1)
- Ecotoxicological Assessment (1)
- Ecotoxicology testing (1)
- Electrochemical (1)
- Elektrochemie (1)
- Elemental Impurities (1)
- Elemental composition (1)
- Emerging brominated flame retardant (1)
- Emission Testing (1)
- Environmental simulation (1)
- Environmental speciation (1)
- Epoxy (1)
- Experimental design (1)
- False Positives (1)
- Fast flow GD (1)
- Fenton’s reagent (1)
- Flow Chemistry (1)
- Fluxomics (1)
- Food contaminants (1)
- Food fermentation (1)
- Food safety (1)
- Forschungsbedarf (1)
- Fragmentation activation (1)
- Fresenius (1)
- Fresenius Lecture (1)
- Fresenius lecture (1)
- Fundamentals (1)
- Gadolinium-based contrast agents (GBCAs) (1)
- Gaschromatography-Mass Spectrometry (1)
- Geological thermometer (1)
- Germanium sulfide (1)
- Glas (1)
- Glass paints (1)
- Graphite furnace (1)
- Gravimtric isotope mixtures (1)
- HR-CS-AAS (1)
- HRMS (1)
- HTS (1)
- Halogens (1)
- Hamonisierung (1)
- Harmonisation (1)
- Harmonisierung (1)
- Hazardous substances (1)
- Heavy crude oil (1)
- Heißgasextraktion (1)
- High repetition-rate (1)
- High-resolution synchrotron XRF (1)
- Histology (1)
- Hochauflösende Massenspektrometrie (1)
- Holographic microscopy (1)
- Human serum (1)
- Humboldt Codices (1)
- Hybridoma (1)
- Hydrazin (1)
- Hydrogen (1)
- Hydrogenation (1)
- Hydrolysis (1)
- Hydrolytic resistance (1)
- Hydrothermal fluid (1)
- Hydroxylation (1)
- Hyphenated techniques (1)
- ICH guideline Q3D (1)
- IDMS (1)
- IIoT (1)
- IR (1)
- Iisotopic signature (1)
- Imaging Mass Cytometry (1)
- Immunoassay (1)
- Implant material (1)
- Indirect Hard Modeling (1)
- Indirect hard modeling (1)
- Indoor Air Quality (1)
- Indoor Products (1)
- Inlet ionization (1)
- Inline NMR Spectroscopy (1)
- Integrated Processes (1)
- Integrating sphere spectroscopy, (1)
- Interferences (1)
- Interlaboratory comparison (1)
- Ion mobility (1)
- Ionmobility spectrometry (1)
- Ionophore Antibiotika (1)
- Ionophore antibiotic (1)
- Isotope anaylsis (1)
- Isotope fractionation (1)
- Isotope purification (1)
- Isotope ratio (1)
- Isotope-labeled (1)
- Isotopic analysis (1)
- Isotopic fingerprints (1)
- Isotopic fractionation (1)
- Kapillarelektrophorese-Massenspektrometrie (1)
- Klassifizierung (1)
- Komplementäre Massenspektrometrie (1)
- LC/HRMS (1)
- Lab-on-a-Chip (1)
- Lab-on-chip (1)
- Labeling (1)
- Labor 4.0 (1)
- Ladder sequencing (1)
- Lapis lazuli (1)
- Laser ablation inductively coupled plasma–mass spectrometry imaging (LA-ICP-MSI) (1)
- Lead isotope composition (1)
- Levitation (1)
- Lignin (1)
- Linear dynamic range (1)
- Lipid metabolism (1)
- Lipidomics (1)
- Liquid chromatography-mass spectrometry (1)
- Low-field NMR Spectroscopy (1)
- Lysosome (1)
- MALDI (1)
- MALDI Imaging (1)
- MALDI-TOF Massenspektrometrie (1)
- MIPs (1)
- MOF (1)
- MS-ICP-MS (1)
- Machine learning (1)
- Macrophages (1)
- Magnesium isotope ratios (1)
- Maia detector (1)
- Mangesium (1)
- Mass cytometry (1)
- Material Science (1)
- Material characterization (1)
- Material science (1)
- Matrices (1)
- Matrix independent calibration (1)
- Matrix-assisted laser desorption ionization–mass spectrometry imaging (MALDI-MSI) (1)
- Measurement uncertainty (1)
- Medieval glasses (1)
- Messunsicherheit (1)
- Metal sublimation (1)
- Method development (1)
- Metrology (1)
- Micro Reactor (1)
- Micro-Hydrocyclone (1)
- Micro-XRF (1)
- Micro-sublimation (1)
- Microemulsion (1)
- Microfluidic (1)
- Microfluidic Chip (1)
- Microparticles (1)
- Microplastic (1)
- Migration (1)
- Modelling (1)
- Modified mycotoxins (1)
- Molecular absorption spectrometry (1)
- Molecular spectrum (1)
- Monensin (1)
- Monoclonal Antibodies (1)
- Monoelemental solutions (1)
- Multicollector-ICP-MS (1)
- Multielemental analysis (1)
- Multielementanalytik in kurzen transienten Signalen (1)
- Multivariate Analyse (1)
- Multivariate Datenanalyse (1)
- Multivariate Datenauswertung (1)
- Multivariate analysis (1)
- Mycotoxin-Biomarker (1)
- NIR (1)
- NIR Spectroscopy (1)
- NIR Spektroskopie (1)
- NIR spectroscopy (1)
- NMR Method Validation (1)
- NMR Spektroskopie (1)
- NMR-Spektroskopie (1)
- NSO-Heterozyklen (1)
- Nahinfrarotspektroskopie (1)
- Nanomaterial (1)
- Nanomaterialien (1)
- Nanoparticles with same nominal diameter (1)
- Nanoparticles with same nominal diameter; surface coating; two-dimensional off-line coupling (1)
- Naphthalene (Nap) (1)
- Neural network (1)
- Nichtmetall-Analytik (1)
- Nichtmetalle (1)
- Niederfeld-NMR-Spektroskopie (1)
- Niobcarbid (1)
- Non-metal analysis (1)
- Non-metals analysis (1)
- Nontargeted approach (1)
- Normen (1)
- Normung (1)
- OBOC (1)
- Online-NMR spectroscopy (1)
- Optimierung (1)
- Ore provenance (1)
- Organic calibration solution (1)
- Organic contaminants (1)
- Outreach (1)
- Oxidative metabolism (1)
- PANIC (1)
- PBFSM (1)
- PGAA (1)
- PIXE (1)
- Pesticide (1)
- Pharmaceutical (1)
- Pharmacopoeial Reference Standards (1)
- Photochemistry (1)
- Photoluminescence (1)
- Photooxidation (1)
- Phytoliths (1)
- Pigment analyses (1)
- Plant tissue (1)
- Plasma diagnostics (1)
- Plasmaspectrochemistry (1)
- Pollenkörner (1)
- Pollutants (1)
- Polymers (1)
- Pomodore (1)
- Pore fluids (1)
- Pozessindustrie (1)
- Priam's treasure (1)
- Primäre Kalibriersubstanzen (1)
- Probennahme (1)
- Process industry (1)
- Provenance studies (1)
- Prozess-Sensoren 4.0 (1)
- Prozesslabor (1)
- Pulsed-GD-SFMS (1)
- Pyrolysis (1)
- Qualitätskontrolle (1)
- Quantification (1)
- Quantum dot (1)
- Quantum yield (1)
- Qumranrollen (1)
- Raman (1)
- Raman spectroscopy (1)
- Real-time imaging (1)
- Real-time process monitoring (1)
- Real-time quality control (1)
- Referenzmaterial-Herstellung (1)
- Reifenabrieb (1)
- Reinstmetalle (1)
- Reinststoffe (1)
- Research (1)
- Rhizopus and Aspergillus oryzae (1)
- SC-ICP-MS (1)
- SI Traceability (1)
- SI-traceable (1)
- SIDA-LC-MS/MS (1)
- SMASH (1)
- Sample-sample bracketing (1)
- Science (1)
- Screening (1)
- Sedimentationskasten (1)
- Sedimenttaionskasten (1)
- Semiconductor (1)
- Sensing (1)
- Si isotope fractionation (1)
- Sialic acid (1)
- Silane (1)
- Simultaneous determination (1)
- Single cell-ICP-MS (1)
- Single particle spectroscopy (1)
- Single particle-ICP-ToF-MS (1)
- Slags (1)
- Smarte Aktoren (1)
- Smarte Laborgeräte (1)
- Solid state NMR (1)
- Sonochemical synthesis (1)
- Sorghum (1)
- Spatial Heterodyne Spectrometer (1)
- Spatial heterodyne spectrometer (1)
- Spectrochemical analysis (1)
- Spectroscopy (1)
- Speiseöle (1)
- Speroid (1)
- Spheroid (1)
- Sportböden (1)
- Stained glass windows (1)
- Stained glasses (1)
- Standardisation (1)
- Standards (1)
- Static Mixing (1)
- Surface chemistry (1)
- Surface coating (1)
- Suzuki coupling (1)
- Synchrotron FTIR (1)
- TGA-FTIR (1)
- TXRF (1)
- Tandem MS (1)
- Target (1)
- Tattoo inks (1)
- Terbutryne (1)
- Testbed (1)
- Therapeutic Drug Monitoring (1)
- Thermal conductivity device (1)
- Thermal decomposition (1)
- Thermal extraction-desorption gas chromatography mass spectrometry (1)
- Thermoanalyse (1)
- Tire particles (1)
- Toxic metals (1)
- Transformation Products (1)
- Transformation products (1)
- Transformations products (1)
- Trialkoxysilane (1)
- Triazine herbicide (1)
- Trichodiene (1)
- Trinkwasser (1)
- Triple isotope fractionation (1)
- Trojan silver artefacts (1)
- Two-dimensional off-line coupling (1)
- UV irradiation (1)
- Ultrasound (1)
- Umwelt (1)
- Umwelt-Speziation (1)
- Umweltsimulation (1)
- Umweltverhalten (1)
- Uncertainty Evaluation (1)
- Underwater LIBS (1)
- VIS- Spektroskopie (1)
- VOC Emission (1)
- Vacuum ionization (1)
- Vacuum ultraviolet (VUV) light (1)
- Validation trial (1)
- Vanadiumcarbid (1)
- Veterinary drugs (1)
- Weighing Uncertainty (1)
- Wolframcarbid (1)
- X-ray and electron diffraction (1)
- X-ray spectroscopy (1)
- Yerba mate tea (1)
- Zearalenone sulfate (1)
- Zinc analysis (1)
- Zn (1)
- a-zearalenol (1)
- bell pepper (1)
- boron (1)
- delta value (1)
- ion optics (1)
- isotope fractionation (1)
- measurement uncertainty (1)
- metabolism (1)
- microplastics, sampling, sampling techniques, water (1)
- single cell-ICP-ToF-MS (1)
- single particle-ICP-ToF-MS (1)
- µJ-DPSS laser (1)
Organisationseinheit der BAM
- 1 Analytische Chemie; Referenzmaterialien (158)
- 1.1 Anorganische Spurenanalytik (46)
- 6 Materialchemie (40)
- 1.4 Prozessanalytik (38)
- 1.6 Anorganische Referenzmaterialien (28)
- 1.7 Organische Spuren- und Lebensmittelanalytik (28)
- 1.8 Umweltanalytik (28)
- 6.6 Physik und chemische Analytik der Polymere (21)
- 6.3 Strukturanalytik (18)
- 1.9 Chemische und optische Sensorik (13)
Eingeladener Vortrag
- nein (98)
Die Identifizierung von Transformationsprodukten (TPs) von Tierarzneimittelwirkstoffen ist wichtig für Gesundheit, Lebensmittel und Umwelt. Monensin (MON) gehört zu den Ionophoren Antibiotika und wird genutzt zum Schutz und zur Behandlung von Kokzidiose bei Geflügel, vorwiegend prophylaktisch in der Geflügelmast. Rückstände können in tierischen Produkten (Geflügel und Eier) aber auch in der Umwelt (Tiermist, Gewässer, Böden) gefunden werden. Verschiedene Transformationsprozesse können auftreten, beginnend bei der Biotransformation in lebenden Organismen bis hin zu biotischen und abiotischen Prozessen in der Umwelt.
Die Kopplung von Elektrochemie und Massenspektrometrie, kurz EC/HRMS, als rein instrumenteller Ansatz zur Simulation von Transformationsprodukten ist seit vielen Jahren in der pharmazeutischen Forschung etabliert. Hierbei wird mithilfe einer elektrochemischen Durchflusszelle der oxidative Metabolismus einer Substanz simuliert und zugleich analysiert. Unter Verwendung von EC/HRMS und LC-HRMS wurde MON elektrochemisch bei Potentialen bis zu 2.5 V vs Pd/H2 oxidiert und die entstehenden TPs mit Metabolismustests mit Rattenlebermikrosomen verglichen. Als Ergebnis wurden verschiedene TPs von MON gefunden und Strukturvorschläge wurden erstellt. Ein Überblick über die detektierten und identifizierten TPs wird dargestellt.
Our study is dedicated to non-destructive characterization of the support and the inks of the DSS.
To that aim we use micro-XRF, 3D- SY-XRF, different IR methods including synchrotron radiation based reflectance spectroscopy, optical and electron microscopy.
The lecture discusses advantages and the shortcomings of the non-destructive testing approach.
Cancer cell lipid class homeostasis is altered under nutrient-deprivation but stable under hypoxia
(2019)
Background: Cancer cells modify the balance between fatty acid (FA) synthesis and uptake under metabolic stress, induced by oxygen/nutrient deprivation. These modifications were shown to alter the levels of individual triglyceride (TG) or phospholipid sub-species. To attain a holistic overview of the lipidomic profiles of cancer cells under stress we performed a broad lipidomic assay, comprising 244 lipids from six major classes. This assay allowed us to perform robust analyses and assess the changes in averages of broader lipid-classes, stratified on the basis of saturation index of their fatty-acyl side chains.
Methods: Global lipidomic profiling using Liquid Chromatography-Mass Spectrometry was performed to assess lipidomic profiles of biologically diverse cancer cell lines cultivated under metabolically stressed conditions.
Results: Neutral lipid compositions were markedly modified under serum-deprived conditions and, strikingly, the cellular level of triglyceride subspecies decreased with increasing number of double bonds in their fatty acyl chains.
In contrast and unexpectedly, no robust changes were observed in lipidomic profiles of hypoxic (2% O2) Cancer cells despite concurrent changes in proliferation rates and metabolic gene expression.
Conclusions: Serum-deprivation significantly affects lipidomic profiles of cancer cells. Although, the levels of individual lipid moieties alter under hypoxia (2% O2), the robust averages of broader lipid classes remain unchanged.
Heute stimmen die meisten Gelehrten und Historiker darin überein, dass die Höhlen von Qumran eine Essener-Bibliothek beherberg-ten. Über ihren Ursprung, sowie die Herkunft der einzelnen Schriften, wird noch immer rege debattiert. Der aktuelle Beitrag präsentiert detaillierte Lösungsansätze zu Klärung der Provenienzfrage der Schriftrollen von Qumran.
Natural sciences play auxiliary role in the studies of manuscripts. The success of their contribution depends strongly on the formulation of the question and the choice of the methods to obtain the requested answer. Therefore, one should try to go beyond the understanding of the basic principles of the scientific analysis.
We will start with a glance at the basic principles of the techniques used in the material science for determination of the elemental composition (X-ray emission) and molecular composition (FTIR & Raman). We will move then to the bench and mobile equipment commonly used in the field of cultural heritage. At the end we will choose a question to be answered and design an ideal experiment that will be modified according to the limitations dictated by on-site conditions.
In the ateliers in the afternoon we will
a) compare two XRF devices that differ in their spatial resolution;
b) use a high resolution microscope (Keyence) to obtain a close look at writing surfaces and materials;
c) we will learn to determine the type of the inks with the help of another microscope (DinoLite AD413T-12V), a usb microscope with visible, UV and NIR illumination;
d) we will learn to use FTIR-ATR device for determination of the type of the writing surface;
e) We will use mobile Raman device for identification of pigments.
Draft standards for the determination of organic pollutants in the solid matter of environmental matrices such as sludge, treated biowaste and soil have been basically developed in the framework of the European standardization project HORIZONTAL. A research project financed by the German Federal Environment Agency was initiated to finalize some of these CEN standard drafts, since fully validated standard procedures are crucial for the evaluation of their reliability in the context of implementation in legislation on environmental health.
Approach: Appropriate test materials (< 2mm particle size) were prepared and homogenized from contaminated soils, sludge and treated biowaste containing polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB), dioxins, furans and dioxin-like-PCB and served, along with reference solutions, as the basis for international interlaboratory comparisons. Performance data of three analytical standard procedures were obtained by the statistical evaluation of results received from 11 to 29 participants per test material.
Results: The overall variation coefficients of reproducibility (between-lab standard deviations) for the sum parameters were roughly between 10 and 35 %. The variation coefficients of repeatability (within-lab standard deviations) range between 3 % and 8 % and show no trend considering the substance groups or matrices.
The highest coefficients of reproducibility were found for the analysis of PAHs, which were between 26 and 35 %, depending on the matrix, whereas 7-17 % reproducibility was observed for toxicity equivalents (TEQ) comprising dioxins, furans and dl-PCB.
Conclusions: Overall, the results confirm that the procedures described in the Technical Specifications are fit for purpose for all three matrices and that the feasibility of the HORIZONTAL approach, to cover several matrices with one standard per analyte, was thereby proven.
Die Untersuchungen sind durch das das DFG Schwerpunktprogramm 1374 für Biodiversitätsforschung motiviert. Anhand des überwachten Abbaus von Totholz soll untersucht werden, welche Auswirkung unterschiedliche Formen und Intensitäten der Landnutzung auf die Biodiversität innerhalb von drei Exploratorien zeigen. Bei den vorangegangenen Studien wurden Nahrungs¬netzte auf organismischer Ebene sowie Klima- und Umgebungsdaten untersucht und die Veränderung des ausgebrachten Totholzes als Masseverlust erfasst. Es wird jedoch erwartet, dass in Anhängigkeit der beteiligten Organismen und Umgebungsparameter verschiedene Mechanismen des Holzabbaus vorliegen, die in unterschiedlichen Abbauraten der Holzkomponenten Lignin, Cellulose und Hemicellulose resultieren. Aus diesem Grund ist die quantitative Untersuchung des Ligningehalts an Hölzern ein wesentlicher Schritt für ein verbessertes Verständnis der Biodiversität in den untersuchten Exploratorien. Um der hohen Probenanzahl, die sich aus der Kontrolle von jeweils 100 Proben (Plots) in den drei Exploratorien für Hölzer aus 13 Baumarten ergibt, gerecht zu werden, wird eine schnelle und effiziente Untersuchungsmethode benötigt. Diese wird derzeit in Form einer NIR-spektroskopischen Bestimmung des Ligningehalts entwickelt. Um basierend auf den NIR Spektren vermahlener Holzproben Lignin und weitere Holzkomponenten korrekt vorherzusagen, muss zunächst basierend auf nasschemischen Analysen ein chemometrisches Modell kalibriert werden. Dazu ist die Charakterisierung von mindestens 20 – 30 Proben, die eine hohe Varianz des Ligningehalts aufweisen, notwendig. Im Vortrag werden erste Untersuchungs¬ergebnisse für die Vorhersage des Ligningehalts von Kiefernhölzern, die für ein Jahr in dem Exploratorium Schorfheide exponiert wurden, vorgestellt. Die anschließende explorative Datenanalyse (PCA) unter Verwendung von insgesamt 28 Variablen zur Beschreibung klimatischer und Umgebungsparameter weist eine Reihe interessanter Korrelationen auf. Demnach ist der Ligningehalt auf der ersten Hauptkomponente (29% erklärte Varianz) positiv mit dem C/N-Verhältnis und negativ mit Landnutzungsindex korreliert. Masseverlust und Temperatur hingegen dominieren die zweite Hauptkomponente (12% erklärte Varianz).
The TED-GC-MS analysis is a two-step method. A sample is first decomposed in a thermogravimetric analyzer (TGA) and the gaseous decomposition products are then trapped on a solid-phase adsorber. Subsequently, the solid-phase adsorber is analyzed with thermal desorption gas chromatography mass spectrometry (TDU-GC-MS). This method is ideally suited for the analysis of polymers and their degradation processes. Here, a new entirely automated System is introduced which enables high sample throughput and reproducible automated fractioned collection of decomposition products. Strengths and limitations of the system configuration are elaborated via three examples focused on practical challenges in materials analysis and identification: i) separate analysis of the components of a wood-plastic-composite material, ii) quantitative determination of weight concentration of the constituents of a polymer blend and iii) quantitative analysis of model samples of microplastics in suspended particulate matter.
Laser-induced plasmas are widely used in many areas of science and technology; examples include spectrochemical analysis, thin film deposition, material processing, and even jet propulsion. Several topics will be addressed. First, general phenomenology of laser-induced plasmas will be discussed. Then, a chemical model will be presented based on a coupled solution of Navier-Stokes, state, radiative transfer, material transport, and chemical (Guldberg-Waage) equations. Results of computer simulations for several chemical systems will be shown and compared to experimental observations obtained by optical imaging, spectroscopy, and tomography. The latter diagnostic tools will also be briefly discussed.