Wissenschaftliche Artikel der BAM
Filtern
Erscheinungsjahr
- 2016 (75) (entfernen)
Dokumenttyp
Sprache
- Englisch (75)
Referierte Publikation
- ja (75) (entfernen)
Schlagworte
- Mechanochemistry (5)
- Nanoparticles (5)
- Additive manufacturing (3)
- In situ (3)
- Metal phosphonate (3)
- NEXAFS (3)
- XRD (3)
- AFM (2)
- DNA origami (2)
- Fluorescence (2)
- MOF (2)
- Mass spectrometry (2)
- Mechanical properties (2)
- Microscopy (2)
- Nanoparticle (2)
- Phase transformation (2)
- Raman spectroscopy (2)
- SAXS (2)
- SERS (2)
- Simulation (2)
- Single particle ICP-MS (2)
- Synthesis (2)
- XPS (2)
- in situ (2)
- mass spectrometry (2)
- 17α-ethinylestradiol (EE2) (1)
- 2-D Welding Simulation (1)
- 3D printing (1)
- Activation energy (1)
- Ag nanoparticles (1)
- Amino acid analysis (1)
- Analysis technique (1)
- Antibody labeling (1)
- Antikörper (1)
- Aqueous solution (1)
- Arzneistoffe (1)
- Assay (1)
- Atomic weight (1)
- Auswaschung (1)
- BLDC (1)
- Biocidal products (1)
- Bioerosion (1)
- Biofilm (1)
- Biofouling (1)
- Biological structure (1)
- Biozidprodukte (1)
- Caenorhabdtis elegans (1)
- Carbon arc-air gouging (1)
- Carbon dots (1)
- Carbonate substrate (1)
- Catalysis (1)
- Cell (1)
- Cellular internalization (1)
- Cellular solids (1)
- Central Asia (1)
- Certified reference materials (1)
- Characterisation techniques (1)
- Characterization and analytical techniques (1)
- Cocrystal (1)
- Column percolation (1)
- Compact NMR (1)
- Computed tomography (1)
- Contaminated soils (1)
- Copolymer sequence (1)
- Corrosion (1)
- Corrosion investigations (1)
- Corrosion resistance (1)
- DFT spectrum simulations (1)
- DNA origami nanostructures (1)
- Debye-Waller factor (1)
- Decline (1)
- DySEM (1)
- Dynamical theory (1)
- EDX (1)
- EXAFS (1)
- Ectoine (1)
- Elastic behavior (1)
- Electromagnetic Force (1)
- Electron backscatter diffraction (1)
- Emerging Pollutants (1)
- Emerging infectious disease (1)
- Encapsulation process (1)
- Endocrine disruption (1)
- Epoxy (1)
- Escherichia coli (1)
- FEFF (1)
- FIB patterning (1)
- FRET (1)
- Factor analysis (1)
- Farben (1)
- Ferromagnetic steel (1)
- Fertilizer (1)
- Fiber Bragg grating (1)
- Fiber Bragg gratings (1)
- Fiber characterization (1)
- Fiber optics sensors (1)
- Field test (1)
- Finit Element Method (1)
- Freilandtest (1)
- Functionalization of fullerenes (1)
- G quadruplex (1)
- GMAW (1)
- Gel-type electrolytes (1)
- Gleeble experiments (1)
- Gold (1)
- Heat treatment (1)
- High-Strength Steel (1)
- High-power Laserbeam Welding (1)
- High-resolution (1)
- High-strength low-alloy steel (1)
- Hydrolysis (1)
- Image analysis (1)
- Imaging technique (1)
- Inconel 718 (1)
- Industrie 4.0 (1)
- Infrared spectroscopy (1)
- Inherent Strain (1)
- Innovation (1)
- Interpass temperature (1)
- Ionic liquids (1)
- Isotope dilution analysis (1)
- Isotope mixture (1)
- Kinematic theory (1)
- Kinetics (1)
- Knowledge spillovers (1)
- LA-ICP-MS (1)
- LA-ICP-MS based immunoassays (1)
- LCA (1)
- LTT (1)
- Langmuir isotherm (1)
- Laser ablation ICP-MS (1)
- Laser beam welding (1)
- Laser metal deposition (1)
- Leaching (1)
- Leaching test (1)
- Ligand analysis (1)
- Lipid Nanodiscs (1)
- MALDI-TOF MS (1)
- MALDI-TOF MS/MS (1)
- MDFEM (1)
- Magnesium (1)
- Magnetic field (1)
- Magnetic nanoparticles (1)
- Magnetostriction (1)
- Maintenance (1)
- Market access (1)
- Martensitic stainless steels (1)
- Matrix influence (1)
- Metal nanoparticles (1)
- Metrology (1)
- Micro-Raman imaging (1)
- Microstrain distribution (1)
- Microstructured fibers (1)
- Microwave (1)
- Milling (1)
- Modal analysis (1)
- Monoklonal (1)
- Motor control (1)
- Multi-attribute decision method (1)
- Multi-criteria decision support (1)
- Mössbauer (1)
- Nano particles (1)
- Nanocomposite (1)
- Nanomaterial classification (1)
- Nanometrology (1)
- Nanotoxicology (1)
- Neurons (1)
- Number-weighted median size (1)
- Online NMR spectroscopy (1)
- Optical incremental encoder (1)
- Organic osmolytes (1)
- PMSM (1)
- PV module (1)
- Paints (1)
- Particle size analysis (1)
- Peptides (1)
- Pesticide parathion-methyl (1)
- Pharmaceuticals (1)
- Pharmazeutika (1)
- Phenylalanine (1)
- Photoligation (1)
- Photonic wire (1)
- Photoswitchable rotaxane (1)
- Pigments (1)
- Plasticity-based Analysis (1)
- Pollinator (1)
- Polycrystalline thin films (1)
- Polymer (1)
- Polymer encapsulant (1)
- Polymers (1)
- Polysarcosine (1)
- Process control (1)
- Protein analysis (1)
- Protein coating (1)
- Proteomics (1)
- Prozessanalytik (1)
- Purity (1)
- Quantification (1)
- Quantitative NMR-Spektroskopie (1)
- Quantum dots (1)
- Quantum yield (1)
- R&D (1)
- REACH regulation (1)
- Raman (1)
- Raman microscopy (1)
- Reaction Stress (1)
- Reaction monitoring (1)
- Reference material (1)
- Regulation (1)
- Repair and overhaul (1)
- Repair welding (1)
- SEM (1)
- Samples (1)
- Scanning electron microscope (1)
- Schadstoffe (1)
- Self assembly (1)
- Servo drive (1)
- Sewage sludge (1)
- Sex reversal (1)
- Silicon nanowire (1)
- Silk Road (1)
- Silver nanoparticles (1)
- Slippage of weakly linked layers (1)
- Small-angle X-ray scattering (1)
- Small-angle x-ray scattering (1)
- Solar cell (1)
- Stability Design (1)
- Standardization (1)
- Strain (1)
- Strategic alliances (1)
- Structured cantilever (1)
- Subaerial and subaquatic biofilm (1)
- Super martensitic filler material (1)
- Surface-enhanced Raman scattering (1)
- Synchrotron radiation (1)
- T-SEM (1)
- Textil (1)
- Textile (1)
- Thermo physical simulation (1)
- Thermomechanical Fatigue (TMF); High Cycle Fatigue (HCF); Cast iron; Fatigue assessment (1)
- Thick-walled steel (1)
- Tiered (1)
- Titanium alloy (1)
- Titanium dioxide (1)
- Transformation induced plasticity (TRIP) (1)
- Tryptophan (1)
- Tyrosine (1)
- Vacuum (1)
- Virulence (1)
- Wall paintings (1)
- Waste-water (1)
- Water structure (1)
- Weld pool support (1)
- Weld residual stress (1)
- Welding (1)
- Welding costs (1)
- Welding process selection (1)
- Welding residual stress (1)
- X-Ray Diffraction (1)
- X-ray computed tomography (1)
- X-ray diffraction (1)
- X-ray microdiffraction (1)
- X-ray tomography (1)
- XAFS (1)
- XANES X-ray absorption near edge structure spectroscopy (1)
- Young’s modulus (1)
- Zinc coatings (1)
- Zinc ferrite (1)
- absolute measurements (1)
- atomic force microscopy (1)
- atomic weight (1)
- carbon black (1)
- cocrystal (1)
- cross-reactivity (1)
- distributed sensor (1)
- failure prevention (1)
- fiber optic sensor (1)
- glass fibre paper (1)
- gold nanoparticles (1)
- graphene (1)
- hydrate (1)
- immunoassay (1)
- irreproducibility (1)
- isotope reference material (1)
- ligand binding assay (1)
- mXRF Micro-X-ray fluorescence spectroscopy (1)
- magnesium (1)
- magnetic saturation (1)
- mechanochemistry (1)
- monoclonal antibody (1)
- multilayer graphene (1)
- nanocomposites (1)
- neutron diffraction (1)
- non-specific binding (1)
- paper retraction (1)
- peer reviewimmunochemistry (1)
- polyionic liquids (1)
- progressive hepatolenticular degeneration (1)
- proton conductors (1)
- pyrazinamide (1)
- quality control (1)
- railway embankment (1)
- replication (1)
- reproducibility crisis (1)
- reversible addition fragmentation chain transfer (RAFT) polymerization (1)
- rubber (1)
- selectivity (1)
- sensing (1)
- silver nanoparticles (1)
- single molecule spectroscopy (1)
- smart geotextile (1)
- spray (1)
- surface enhanced Raman scattering (1)
- surface modification (1)
- x-ray diffraction (1)
In Near Edge X-Ray Absorption Fine Structure (NEXAFS) spectroscopy X-Ray photons are used to excite tightly bound core electrons to low-lying unoccupied orbitals of the system. This technique offers insight into the electronic structure of the system as well as useful structural information. In this work, we apply NEXAFS to two kinds of imidazolium based ionic liquids ([CnC₁im]⁺[NTf₂]⁻ and [C₄C₁im]⁺[I]⁻). A combination of measurements and quantum chemical calculations of C K and N K NEXAFS resonances is presented. The simulations, based on the transition potential density functional theory method (TP-DFT), reproduce all characteristic features observed by the experiment. Furthermore, a detailed assignment of resonance features to excitation centers (carbon or nitrogen atoms) leads to a consistent interpretation of the spectra.
A novel photoswitchable rotaxane was synthesised and its switching behaviour in solution was analysed with NMR and UV-Vis. A monolayer of rotaxanes was deposited on glass surfaces and the on-surface photoswitching was investigated. Angle-resolved NEXAFS spectra revealed a preferential orientation that reversibly changes upon switching.
The folding of single-stranded telomeric DNA into guanine (G) quadruplexes is a conformational change that plays a major role in sensing and drug targeting. The telomeric DNA can be placed on DNA origami nanostructures to make the folding process extremely selective for K+ ions even in the presence of high Na+ concentrations. Here, we demonstrate that the K+-selective G-quadruplex formation is reversible when using a cryptand to remove K+ from the G-quadruplex. We present a full characterization of the reversible switching between single-stranded telomeric DNA and G-quadruplex structures using Förster resonance energy transfer (FRET) between the dyes fluorescein (FAM) and cyanine3 (Cy3). When attached to the DNA origami platform, the G-quadruplex switch can be incorporated into more complex photonic networks, which is demonstrated for a three-color and a four-color FRET cascade from FAM over Cy3 and Cy5 to IRDye700 with G-quadruplex-Cy3 acting as a switchable transmitter.
The properties of the encapsulant are critical to the long-term performance of photovoltaic (PV) modules under the influence of sunlight including UV, elevated temperature, humidity and diffusion of oxygen. Encapsulation process represents a bout 40% of the whole PV module cost. The introduction of new non-EVA encapsulant material type "Low-Cost, High-Performance" should provide a solution to outdoor yellowing degradation problems. The emerging encapsulant materials exhibit a good compatibility with emerging PV solar cells for long term durability. This new generation of encapsulant materials has the advantage to improve e the PV module performances and long term durability for specific climate like desert regions. This scientific contribution presents an overview of the different encapsulant materials currently on the market, the general requirements of the emerging encapsulant materials and characterizations techniques for degradation, diagnostic and reliability lifetime estimation in the framework of Algerian renewable energy strategy.
Self-assembling biomolecules provide attractive templates for the preparation of metallic nanostructures. However, the intuitive transfer of the “outer shape” of the assembled macromolecules to the final metallic particle depends on the intermolecular forces among the biomolecules which compete with interactions between template molecules and the metal during metallization. The shape of the bio-template may thus be more dynamic than generally assumed. Here, we have studied the metallization of phospholipid nanodiscs which are discoidal particles of ~10 nm diameter containing a lipid bilayer ~5 nm thick. Using negatively charged lipids, electrostatic adsorption of amine-coated Au nanoparticles was achieved and followed by electroless gold deposition. Whereas Au nanoparticle adsorption preserves the shape of the bio-template, metallization proceeds via invasion of Au into the hydrophobic core of the nanodisc. Thereby, the lipidic phase induces a lateral growth that increases the diameter but not the original thickness of the template. Infrared spectroscopy reveals lipid expansion and suggests the existence of internal gaps in the metallized nanodiscs, which is confirmed by surface-enhanced Raman scattering from the encapsulated lipids. Interference of metallic growth with non-covalent interactions can thus become itself a shape-determining factor in the metallization of particularly soft and structurally anisotropic biomaterials.
Background: Biocidal products can be sources of active substances in surface waters caused by weathering of treated articles. Marketing and use of biocidal products can be limited according to the European Biocidal Products Regulation if unacceptable risks to the environment are expected. Leaching of active substances from treated articles was observed in field experiments to obtain information on leaching processes and investigate the suitability of a proposed test method.
Results: Leaching under weathering conditions proceeds discontinuously and tends to decrease with duration of exposure. It mainly depends on the availability of water, but is also controlled by transport processes within the materials and stability of the observed substances. Runoff amount proved to be a suitable basis to compare results from different experiments. Concentrations of substances are higher in runoff collected from vertical surfaces compared to horizontal ones, whereas the leached amounts per surface area are higher from horizontal surfaces. Gaps in mass balances indicate that additional processes such as degradation and evaporation may be relevant to the fate of active substances in treated articles. Leached amounts of substances were considerably higher when the materials were exposed to intermittent water contact under laboratory conditions as compared to weathering of vertically exposed surfaces.
Conclusions: Experiences from the field experiments were used to define parameters of a procedure that is now provided to fulfil requirements of the Biocidal Products Regulation. The experiments confirmed that the amount of water which is in contact with exposed surfaces is the crucial parameter determining leaching of substances.
Multifunctional composite nanoprobes consisting of iron oxide nanoparticles linked to silver and gold nanoparticles, Ag–Magnetite and Au–Magnetite, respectively, were introduced by endocytic uptake into cultured fibroblast cells. The cells containing the non-toxic nanoprobes were shown to be displaceable in an external magnetic field and can be manipulated in microfluidic channels. The distribution of the composite nanostructures that are contained in the endosomal system is discussed on the basis of surfaceenhanced Raman scattering (SERS) mapping, quantitative laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) micromapping, and cryo soft X-ray tomography (cryo soft-XRT). Cryo soft-XRT of intact, vitrified cells reveals that the composite nanoprobes form intra-endosomal aggregates. The nanoprobes provide SERS signals from the biomolecular composition of their surface in the endosomal environment. The SERS data indicate the high stability of the nanoprobes and of their plasmonic properties in the harsh environment of endosomes and lysosomes. The spectra point at the molecular composition at the surface of the Ag–Magnetite and Au–Magnetite nanostructures that is very similar to that of other Composite structures, but different from the composition of pure silver and gold SERS nanoprobes used for intracellular investigations. As shown by the LA-ICP-MS data, the uptake efficiency of the magnetite composites is approximately two to three times higher than that of the pure gold and silver nanoparticles.
The successful mechanochemical syntheses of three cadmium phenylphosphonates indicates that mechanochemistry is ideally suited for synthesizing metal phosphonates. With this powerful synthesis tool it is possible to synthesize rapidly and efficiently both known and novel phosphonates. The Crystal structures of the two new compounds, and, were solved from PXRD data. They contain monodeprotonated phenylphosphonate and neutral phenylphosphonic acid ligands. The synthesis pathways of all three compounds were investigated in situ. A diffusion mechanism is corroborated by our findings.
Intermediates could be detected and identified. The kinetically favored product (3) could always be detected during the syntheses. The thermodynamic stability of the compounds and the stoichiometric ratio of the starting materials are the two directing factors for the synthesis of the final products.
We report on the development of ultra-small core-shell silver nanoparticles synthesized by an up-scaled modification of the polyol process. It is foreseen to use these thoroughly characterized particles as reference material to compare the catalytic and biological properties of functionalized silver nanoparticles. Small-angle X-ray scattering (SAXS) analysis reveal a narrow size distribution of the silver cores with a mean radius of RC = 3.0 nm and a distribution width of 0.6 nm. Dynamic light scattering (DLS) provides a hydrodynamic radius of RH = 10.0 nm and a PDI of 0.09. The particles’ surface is covered with poly(acrylic acid) (PAA) forming a shell with a thickness of 7.0 nm, which provides colloidal stability lasting for more than six months at ambient conditions. The PAA can be easily exchanged by biomolecules to modify the surface functionality. Replacements of PAA with glutathione (GSH) and bovine serum albumin (BSA) have been performed as examples. We demonstrate that the particles effectively catalyze the reduction of 4-nitrophenol to 4-aminophenol with sodium borohydride. With PAA as stabilizer, the catalytic activity of 436 ± 24 L g⁻¹ s⁻¹ is the highest reported in literature for silver nanoparticles. GSH and BSA passivate the surface substantially resulting in a catalytic activity of 77.6 ± 0.9 and 3.47 ± 0.50 L g⁻¹ s⁻¹, respectively.
Advances in scanning electron microscopy (SEM) enable the high-resolution imaging of single nanoparticles (NPs) with sizes well below 10 nm. The SEM analysis in transmission mode (T-SEM) of NPs on thin film supports has many benefits when compared to the analysis of NPs on bulk substrates. The enhanced material (mass – thickness) contrast of the T-SEM imaging mode is well suited for in-depth and, particularly valuable, to very accurate, traceable, lateral dimensional measurements of NPs. Compared to samples prepared on bulk substrates, T-SEM with energy dispersive X-ray spectroscopy (EDS) achieves a drastically improved spatial resolution of the emitted X-rays. The poor signal-to-noise ratio of the X-ray spectra emitted by a single nanoparticle (NP) can be improved by the use of high-sensitivity (high collection solid angle) silicon drift (SDD), energy-dispersive X-ray spectrometers (EDS). The EDS spectral imaging of a single NP with a spatial resolution below 10 nm has become possible. This is demonstrated by means of various examples of nanostructures. Advanced data processing of T-SEM/EDS results sets the stage for the automated classification of NPs by feature analysis. This method combines the detection of morphological structures of interest by image processing of T-SEM micrographs with the chemical classification by EDS.