TY - CHAP A1 - Krumbein, W. A1 - Gorbushina, Anna ED - Watt, J. ED - Tidblad, J. ED - Kucera, V. ED - Hamilton, R. T1 - Some aspects of biological weathering and air pollution KW - Cyanobacteria KW - Geobiology KW - Microcolonial fungi KW - Rock inhabiting fungi-phototroph symbioses KW - Soil formation KW - Subaerial biofilms KW - Weathering PY - 2009 SN - 978-0-387-84892-1 DO - https://doi.org/10.1007/978-0-387-84893-8_5 IS - Chapter 5 SP - 127 EP - 145 PB - Springer Science + Business Media AN - OPUS4-20886 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Feigl, Michael A1 - Nofz, Marianne A1 - Sojref, Regine A1 - Dressler, Martin A1 - Pulz, Robert A1 - Rehmer, Birgit A1 - Feldmann, Ines A1 - Sabel, Martin T1 - Aluminiumoxidschichten für den Oxidationsschutz von Hochtemperaturlegierungen N2 - Effektive Al2O3-Keramik-Schutzschichten könnten die Verwendung preiswerterer Legierungen für Hochtemperaturanwendungen ermöglichen. Die Anforderungen an diese Schichten sind eine gute Haftung, chemische Stabilität und Dichtheit gegen die Umgebungsatmosphäre. T2 - DKG-Jahrestagung/Symposium Hochleistungskeramik CY - Aachen, Germany DA - 23.03.2009 KW - Schichtherstellung KW - Schichttestung KW - Hochtemperaturanwendungen PY - 2009 AN - OPUS4-35836 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thünemann, Andreas A1 - Knappe, Patrick A1 - Bienert, Ralf A1 - Weidner, Steffen T1 - Online coupling of field-flow fractionation with SAXS and DLS for polymer analysis N2 - We report on a hyphenated polymer analysis method consisting of asymmetrical flow field-flow fractionation (A4F) coupled online with small-angle X-ray scattering (SAXS) and dynamic light scattering (DLS). A mixture of six poly(styrene sulfonate)s with molar masses in the range of 6.5 × 103 to 1.0 × 106 g mol-1 was used as a model system for polyelectrolytes in aqueous solutions with a broad molar mass distribution. A complete polymer separation and analysis was performed in 60 min. Detailed information for all polymer fractions are available on i) the radii of gyration, which were determined from the SAXS data interpretation in terms of the Debye model (Gaussian chains), and ii) the diffusion coefficients (from DLS). We recommend using the A4F-SAXS-DLS coupling as a possible new reference method for the detailed analysis of complex polymer mixtures. Advantages of the use of SAXS are seen in comparison to static light scattering for polymers with radii of gyration smaller then 15 nm, for which only SAXS produces precise analytical results on the size of the polymers in solution. PY - 2009 DO - https://doi.org/10.1039/b9ay00107g SN - 1759-9660 SN - 1759-9679 VL - 1 SP - 177 EP - 182 PB - RSC Publ. CY - Cambridge AN - OPUS4-20567 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gorbushina, Anna A1 - Broughton, W.J. T1 - Microbiology of the atmosphere-rock interface: How biological interactions and physical stresses modulate a sophisticated microbial ecosystem N2 - Life at the atmosphere-lithosphere boundary is an ancient terrestrial niche that is sparsely covered by thin subaerial biofilms. The microbial inhabitants of these biofilms (a) have adapted to all types of terrestrial/subaerial stresses (e.g., desiccation, extreme temperatures, low nutrient availability, intense solar radiation), (b) interact with minerals that serve as both a dwelling and a source of mineral nutrients, and (c) provoke weathering of rocks and soil formation. Subaerial communities comprise heterotrophic and phototrophic microorganisms that support each other's lifestyle. Major lineages of eubacteria associated with the early colonization of land (e.g., Actinobacteria, Cyanobacteria) are present in these habitats along with eukaryotes such as microscopic green algae and ascomycetous fungi. The subaerial biofilm inhabitants have adapted to desiccation, solar radiation, and other environmental challenges by developing protective, melanized cell walls, assuming microcolonial architectures and symbiotic lifestyles. How these changes occurred, their significance in soil formation, and their potential as markers of climate change are discussed below. KW - Cyanobacteria KW - Geobiology KW - Microcolonial fungi KW - Rock inhabiting KW - Fungi-phototroph symbioses KW - Soil formation KW - Subaerial biofilms KW - Weathering PY - 2009 DO - https://doi.org/10.1146/annurev.micro.091208.073349 SN - 0066-4227 VL - 63 SP - 431 EP - 450 PB - Annual Reviews Inc. CY - Palo Alto, CA, USA AN - OPUS4-20243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Falkenhagen, Jana A1 - Weidner, Steffen T1 - Determination of critical conditions of adsorption for chromatography of polymers N2 - Liquid chromatography (LC) at critical conditions of adsorption was used to separate various poly(ethylene oxides), poly(propylene oxides) and their copolymers. For the first time, the determination of the critical conditions by means of Ultra Performance Liquid Chromatography (UPLC) coupled to Electrospray Ionization Time-of-flight Mass Spectrometry (ESI-TOF MS) is reported. In contrast to established, mostly laborious routines to find suitable chromatographic separation conditions, this coupling enables a very fast adjustment of parameters. Similar to LC Matrix-assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (LC/MALDI MS) coupling, a two-dimensional analysis of homo- and copolymers regarding its functionality type and molecular weight distribution, as well as copolymer composition, can be performed simultaneously. Furthermore, there is no need for using polymer standards for the determination of critical conditions or Size Exclusion Chromatography calibration. KW - Polymere KW - UPLC KW - ESI-Massenspektrometrie KW - Kopplung PY - 2009 DO - https://doi.org/10.1021/ac8019784 SN - 0003-2700 SN - 1520-6882 VL - 81 IS - 1 SP - 282 EP - 287 PB - American Chemical Society CY - Washington, DC AN - OPUS4-19619 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kricheldorf, H.R. A1 - Yashiro, T. A1 - Weidner, Steffen T1 - Isomerization-free polycondensations of maleic anhydride with alpha,omega-alkanediols KW - Polymerisation KW - Polykondensation KW - MALDI Massenspektrometrie PY - 2009 DO - https://doi.org/10.1021/ma9009356 SN - 0024-9297 SN - 1520-5835 VL - 42 IS - 17 SP - 6433 EP - 6439 PB - American Chemical Society CY - Washington, DC AN - OPUS4-20930 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -