TY - JOUR A1 - Kunte, Hans-Jörg A1 - Lentzen, G. A1 - Galinski, E. T1 - Industrial production of the cell protectant ectoine: protection mechanisms, processes, and products N2 - Bacteria, Archaea and Eukarya can adapt to Saline environments by accumulating compatible solutes in order to maintain an osmotic equilibrium. Compatible solutes are of diverse chemical structure (sugars, polyols, amino acid derivatives) and are beneficial for bacterial cells not only as osmoregulatory solutes, but also as protectants of proteins by mitigating detrimental effects of freezing, drying and high temperatures. The aspartate derivative ectoine is a wide spread compatible solute in Bacteria and possesses additional protective properties compared with other compatible solutes, and stabilizes even whole cells against stresses such as UV radiation or cytotoxins. The protective properties of ectoine for proteins can be explained by its strong (kosmotropic) interaction with water and subsequent exclusion from Protein surface, the decrease of the solubility of the peptide backbone and the strengthening of intramolecular hydrogen bonds (secondary structures). The stabilizing and UV-protective properties of ectoine attracted industry, which saw the potential to market ectoine as a novel active component in health care products and cosmetics. In joint efforts of industry and research large-scale fermentation procedures have been developed with the halophilic bacterium Halomonas elongata used as a producer strain. The two key technologies that allow for the annual production of ectoine on a scale of tons are the bacterial milking procedure and the development and application of ectoine-excreting mutants (“leaky” mutant). The details of these two procedures including the strain development and Fermentation processes will be introduced and current and future applications of ectoine will be discussed. KW - Bacterial milking KW - Batch fermentation KW - Continuous culture KW - Ectoine excretion KW - Hofmeister effect KW - Kosmotrope KW - “leaky” mutant KW - Osmophobic effect KW - Protein protection KW - Preferential exclusion PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-376805 DO - https://doi.org/10.2174/22115501113026660037 SN - 2211-551X VL - 3 IS - 1 SP - 10 EP - 25 PB - Bentham Science AN - OPUS4-37680 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zscherpel, Uwe A1 - Ewert, Uwe T1 - Electronic reference images for flaw indications in welds and castings N2 - Since decades the evaluation of flaw indications on radiographs from welds or castings are based on well accepted reference film catalogues from organizations like IIW (weldments), ASTM (castings) or DGZfP (D5 recommendation on heavy steel castings). Today, the transformation of classical film radiography to the digital world is in full progress. Some ASTM standards do not permit the evaluation of digital radiographs in reference to film catalogues. Therefore, these reference film catalogues have to be converted into the digital age too. BAM is supporting this transition by high definition film scanning. The result is a corresponding reference image catalogue. The different standard organizations selected different ways to distribute the digital data. ASTM used high definition film scanning at 10 μm pixel size and distribution of a huge amount of high-res data via DVD. The user sub-samples these high-res data during catalogue import to the resolution of his system. The comparison is done by synchronized image viewing on the computer work station. IIW recently decided to distribute their ISO 5817 reference images installed on tablets, which are used for image viewing too. The tablet image has to be compared with the digital image on the system monitor. DGZfP transformed their D5 reference radiographs into a PDF for monitor viewing. This is the simplest and cheapest solution, but still allows the full usage of the catalogue in the digital era. The status of ongoing work in progress will be discussed. T2 - WCNDT 2016 CY - Munich, Germany DA - 13.06.2016 KW - Castings KW - NDT KW - RT KW - Radiography KW - Discontinuities KW - Catalogues KW - Welds PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-377306 UR - http://ndt.net/?id=19310 SN - 1435-4934 VL - 21 IS - 7 SP - 1 EP - 8 PB - NDT.net CY - Kirchwald AN - OPUS4-37730 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rosemann, Paul A1 - Müller, Christina A1 - Meyer, A. A1 - Halle, T. T1 - Influence of nitrogen on the corrosion resistance of martensitic stainless steels N2 - The corrosion resistance of martensitic stainless steels (MSS) depends strongly on the chemical composition and the applied heat treatment. Both determines the distribution of the alloying elements in the microstructure and the resulting material properties. The addition of nitrogen is known to be beneficial for the pitting corrosion resistance of stainless steels. In case of MSS this effect is not only connected to nitrogen itself because nitrogen can be used to substitute carbon which also influences the result of the heat treatment process. This paper shows the effect of nitrogen on the corrosion resistance in relation to the hardening process of MSS. Therefore the effects of austenitization duration, austenitization temperature and cooling rate on microstructure, hardness and corrosion resistance were studied on the MSS X30CrMoN15 1 and X50CrMoV15. The effect of different cooling rates was studied in the range of > 100 K/s down to 1 K/s using the jominy end quench test. The changes in corrosion resistance were detected with electrochemical potentiodynamic reactivation (EPR) and by the determination of critical pitting potentials. Besides this experimental approach thermodynamic calculations with the software thermocalc will be presented and used for the interpretation of the effect of nitrogen on the corrosion resistance of MSS. T2 - 18th Chemnitz Seminar on Materials Engineering – 18. Werkstofftechnisches Kolloquium CY - Chemnitz, Germany KW - Martensitic stainless steels KW - Corrosion resistance KW - Heat treatment PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-366956 DO - https://doi.org/10.1088/1757-899X/118/1/011002 VL - 118 IS - 1 SP - 19 EP - 19 PB - IOP Publishing AN - OPUS4-36695 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scherb, Tobias A1 - Kimber, S. A. J. A1 - Stephan, Christiane A1 - Henry, P. F. A1 - Schumacher, G. A1 - Escolástico, S. A1 - Serra, J. M. A1 - Seeger, J. A1 - Just, J. A1 - Hill, A.H. A1 - Banhart, J. T1 - Nanoscale order in the frustrated mixed conductor La5.6WO12-Delta N2 - This article reports a comprehensive investigation of the average and local structure of La5.6WO12-δ, which has excellent mixed proton, electron and oxide ion conduction suitable for device applications. Synchrotron X-ray and neutron powder diffraction show that a cubic fluorite supercell describes the average structure, with highly disordered lanthanum and oxide positions. On average, the tungsten sites are sixfold coordinated and a trace [3.7 (1.3)%] of anti-site disorder is detected. In addition to sharp Bragg reflections, strong diffuse neutron scattering is observed, which hints at short-range order. Plausible local configurations are considered and it is shown that the defect chemistry implies a simple 'chemical exchange' interaction that favours ordered WO6 octahedra. The local model is confirmed by synchrotron X-ray pair distribution function analysis and EXAFS experiments performed at the La K and W L-3 edges. It is shown that ordered domains of similar to 3.5 nm are found, implying that mixed conduction in La5.6WO12-δ is associated with a defective glassy-like anion sublattice. The origins of this ground state are proposed to lie in the nonbipartite nature of the face-centred cubic lattice and the pairwise interactions which link the orientation of neighbouring octahedral WO6 sites. This 'function through frustration' could provide a means of designing new mixed conductors. KW - neutron diffraction KW - x-ray diffraction KW - proton conductors PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-366756 DO - https://doi.org/10.1107/S1600576716006415 SN - 1600-5767 VL - 49 IS - Issue 3 SP - 997 EP - 1008 PB - International Union of Crystallography CY - Chester, UK AN - OPUS4-36675 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meiling, T. A1 - Cywinski, P. A1 - Bald, Ilko T1 - White carbon: Fluorescent carbon nanoparticles with tunable quantum yield in a reproducible green synthesis N2 - In this study, a new reliable, economic, and environmentally-friendly one-step synthesis is established to obtain carbon nanodots (CNDs) with well-defined and reproducible photoluminescence (PL) properties via the microwave-assisted hydrothermal treatment of starch and Tris-acetate-EDTA (TAE) buffer as carbon sources. Three kinds of CNDs are prepared using different sets of above mentioned starting materials. The as-synthesized CNDs: C-CND (starch only), N-CND 1 (starch in TAE) and N-CND 2 (TAE only) exhibit highly homogenous PL and are ready to use without need for further purification. The CNDs are stable over a long period of time (>1 year) either in solution or as freeze-dried powder. Depending on starting material, CNDs with PL quantum yield (PLQY) ranging from less than 1% up to 28% are obtained. The influence of the precursor concentration, reaction time and type of additives on the optical properties (UV-Vis absorption, PL emission spectrum and PLQY) is carefully investigated, providing insight into the chemical processes that occur during CND formation. Remarkably, upon freeze-drying the initially brown CND-solution turns into a non-fluorescent white/slightly Brown powder which recovers PL in aqueous solution and can potentially be applied as fluorescent marker in bio-imaging, as a reduction agent or as a photocatalyst. KW - Carbon dots KW - Quantum yield KW - Fluorescence KW - Nanoparticles PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-367204 DO - https://doi.org/10.1038/srep28557 VL - 6 SP - Article 28557, 1 EP - 9 PB - Nature Publishing Group AN - OPUS4-36720 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nilsson, R. H. A1 - Taylor, A. F. S. A1 - Adams, R. I. A1 - Baschien, C. A1 - Bengtsson-Palme, J. A1 - Cangren, P. A1 - Coleine, C. A1 - Iršėnaitė, R. A1 - Martin-Sanchez, Pedro Maria A1 - Meyer, W. A1 - Oh, S.-Y. A1 - Sampaio, J. P. A1 - Seifert, K. A. A1 - Sklenář, F. A1 - Stubbe, D. A1 - Suh, S.-O. A1 - Summerbell, R. A1 - Svantesson, S. A1 - Unterseher, M. A1 - Visagie, C. M. A1 - Weiss, M. A1 - Woudenberg, J. HC. A1 - Wurzbacher, C. A1 - Van den Wyngaert, S. A1 - Yilmaz, N. A1 - Yurkov, A. A1 - Kõljalg, U. A1 - Abarenkov, K. A1 - Daniel, H.-M. A1 - Glassman, S. I. A1 - Hirooka, H. A1 - Irinyi, L. T1 - Taxonomic annotation of public fungal ITS sequences from the built environment – a report from an April 10–11, 2017 workshop (Aberdeen, UK) N2 - Recent DNA-based studies have shown that the built environment is surprisingly rich in fungi. These indoor fungi – whether transient visitors or more persistent residents – may hold clues to the rising levels of human allergies and other medical and building-related health problems observed globally. The taxo¬nomic identity of these fungi is crucial in such pursuits. Molecular identification of the built mycobiome is no trivial undertaking, however, given the large number of unidentified, misidentified, and technically compromised fungal sequences in public sequence databases. In addition, the sequence metadata required to make informed taxonomic decisions – such as country and host/substrate of collection – are often lacking even from reference and ex-type sequences. Here we report on a taxonomic annotation workshop (April 10–11, 2017) organized at the James Hutton Institute/University of Aberdeen (UK) to facilitate reproducible studies of the built mycobiome. The 32 participants went through public fungal ITS bar¬code sequences related to the built mycobiome for taxonomic and nomenclatural correctness, technical quality, and metadata availability. A total of 19,508 changes – including 4,783 name changes, 14,121 metadata annotations, and the removal of 99 technically compromised sequences – were implemented in the UNITE database for molecular identification of fungi (https://unite.ut.ee/) and shared with a range of other databases and downstream resources. Among the genera that saw the largest number of changes were Penicillium, Talaromyces, Cladosporium, Acremonium, and Alternaria, all of them of significant importance in both culture-based and culture-independent surveys of the built environment. KW - Indoor mycobiome KW - Built environment KW - Molecular identification KW - Fungi KW - Taxonomy KW - Systematics KW - Sequence annotation KW - Metadata KW - Open data PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-438949 DO - https://doi.org/10.3897/mycokeys.28.20887 SN - 1314-4049 SN - 1314-4057 VL - 28 SP - 65 EP - 82 PB - Pensoft Publishers CY - Washington, DC AN - OPUS4-43894 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zerbst, Uwe A1 - Madia, Mauro A1 - Beier, H. Th. T1 - Fatigue strength and life determination of weldments based on fracture mechanics N2 - The paper provides an overview on the results of a German cluster project on the use of fracture mechanics to the determination of the fatigue strength of weldments with fatigue cracks originating at the weld toes. The approach includes (a) a concept for short crack propagation for which the common ΔK concept is not applicable and the crack closure effects are still being gradually build-up, (b) a method for determining fatigue life relevant initial crack sizes as they are needed in any fracture mechanics analysis and (c) multiple cracking and crack coalescence at load levels higher than the endurance limit. The analyses are stochastically performed. Both, the endurance limit and the finite life branch of the S-N curve are determined. Besides a brief introduction into the approach, validation examples are presented. These comprise different weldment types (butt welds, cross joints and longitudinal stiffened plates), two steels (S355NL and S960QL) of quite different strengths, different weld geometries due to different welding techniques (WIG, MAG), as-welded and stress relieved welds and different stress ratios varying from R = -1 to R = 0.5. T2 - FDMD 2017 CY - Lecco, Italy DA - 19.09.2017 KW - Weldments KW - Fatigue strength KW - Fracture mechanics KW - Initial crack size KW - Short crack propagation KW - Multiple crack propagation PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-438500 DO - https://doi.org/10.1016/j.prostr.2017.11.106 SN - 2452-3216 VL - 7 SP - 407 EP - 414 PB - ScienceDirect CY - Lecco, Italy AN - OPUS4-43850 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zerbst, Uwe A1 - Hilgenberg, Kai T1 - Damage development and damage tolerance of structures manufactured by selective laser melting - a review N2 - The additive manufacturing technology of Selective Laser Melting (SLM) experiences a rapid development within an increasing marked of quite different application fields. The properties of SLM materials and structures are influenced by a number of tech-nological parameters such as the metal powder (particle size, homogeneity, cleanliness), the laser tool (power, beam diameter, pulse lengths), the scanning operation (speed, sequence and orientation of melting paths), parameters of the over-all equipment (design and preheating of the base plate, currents and turbulence in the protective gas atmosphere) and, last not least, the hatching strategy including the build-up direction of the structure with respect to the loading direction of the component. For the perspective use of SLM structures as load carrying, safety-relevant components the knowledge of their mechanical properties is necessary. It is essential to understand these in the context of the manufacturing-related features and at the back-ground of the basic characteristics of metallic materials: crystal lattice, microstructure and material defects. The paper provides an overview on factors which affect the mechanical parameters stiffness, strength, ductility, toughness, fatigue crack propagation and fatigue strength in the context of selective laser melting. T2 - FDMD 2017 CY - Lecco, Italy DA - 19.09.2017 KW - Fatigue strength KW - Fracture mechanics KW - Initial crack size KW - Short crack propagation KW - Multiple crack propagation PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-438511 DO - https://doi.org/10.1016/j.prostr.2017.11.071 SN - 2452-3216 VL - 7 SP - 141 EP - 148 PB - ScienceDirect CY - Lecco, Italy AN - OPUS4-43851 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scherz, Franziska A1 - Krop, U. A1 - Monks, K. A1 - Weller, Michael G. T1 - Antikörperreinigung mit Glasmonolithen - Vereinfachung von Affinitätstrennungen mit HPLC-Systemen N2 - Druckstabile Glasmonolithen ermöglichen eine schnelle und unkomplizierte Reinigung von Antikörpern, z.B. aus Serum oder Zellkulturüberständen. Die sehr gute Regenerierbarkeit lässt eine lange Lebensdauer der Säulen erwarten, was die Kosten pro Probe niedrig hält. KW - Borosilicatglas KW - Immunglobuline KW - IgG KW - Serum KW - Plasma KW - Protein A KW - Protein G KW - Affinitätschromatographie KW - Agarose KW - Carrier-Material KW - Stationäre Phase KW - Immobilisierung KW - Highspeed KW - Trennung KW - Reinigung KW - Downstream Processing PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-445330 UR - http://www.git-labor.de/forschung/materialien/antikoerperreinigung-mit-glasmonolithen SN - 0016-3538 VL - 62 IS - 3 SP - 24 EP - 25 PB - Wiley-VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-44533 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Muelow-Stollin, Ulrike A1 - Lehnik-Habrink, Petra A1 - Kluge, Stephanie A1 - Bremser, Wolfram A1 - Piechotta, Christian T1 - Efficiency Evaluation of Extraction Methods for Analysis of OCPs and PCBs in Soils of Varying TOC N2 - Organochlorine pesticides and polychlorinated biphenyls are toxic, carcinogenic, and have a high potential for bioaccumulation. Due to their stability, they are still considered an environmental problem even though the use of most of them has been phased out several decades ago. Soil is a matrix which can retain these contaminants to a great extent. This ability is often associated with the total organic carbon content (TOC). In order to judge the pollution status of soil and to make monitoring data more easily comparable a simple, yet robust extraction method is needed. Agitation solid-liquid-extraction is well suited for this purpose. However, the influence of TOC on the analyte recovery has to be known. For the presented study, 12 organochlorine pesticides and 7 polychlorinated biphenyls were spiked into four model soils with organic carbon contents between 1.6% - 13.3%. The matrices were extracted using solid-liquid extraction between 45 minutes and 16 hours. For comparison, all soils were also extracted using pressurised liquid extraction and Soxhlet extraction. After clean-up the extracts were measured using a gas chromatography-mass spectrometry (GC-MS) system. Statistical analysis of the results implied that the TOC content of the soils did not have significant influence on the extraction efficiency. A longer solid-liquid extraction time did not necessarily increase analyte recovery: Extraction for one hour resulted in 88% recovery while 16 hour extraction led to 89%. Thus, the efficiency of all the methods was comparable for all model soils. Additional investigations regarding GC liner performance highlighted the need for isotopically labelled standards during the analysis of thermolabile pesticides. KW - POP KW - Soil organic matter KW - Solid-liquid-extraction KW - Pressurised liquid extraction PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-430238 DO - https://doi.org/10.4236/jep.2017.86045 SN - 2152-2219 VL - 08 IS - 06 SP - Article ID:77202, 693 EP - 713 PB - Scientific Research Publishing AN - OPUS4-43023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -