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51.
H. J. Weber 《Fortschritte der Physik》1976,24(1):1-36
Some aspects of medium energy (∼ 150 MeV to 1 GeV) proton and pion scattering theory from complex nuclei are reviewed with emphasis on inelastic scattering as a tool to extract nuclear structure information. 相似文献
52.
54.
Thomas Höche † Peter A. van Aken Michael Grodzicki Frank Heyroth Ralf Keding Reinhard Uecker 《哲学杂志》2013,93(29):3117-3132
Based on cluster molecular orbital calculations, high-energy resolution (ΔE?~ 0.4?eV) Ti–L2,3 electron energy loss near-edge structures of single-crystalline and glassy Ba2TiGe2O8 are interpreted. The finding that the Ti–L2,3 near-edge structure of the Ba2TiGe2O8 single crystal possesses less pronounced peaks than the glass under identical experimental conditions can be attributed to distinct distortions of the titanium environment caused by the very strong one-dimensional structural modulation hosted by the Ba2TiGe2O8 crystal lattice. As lattice periodicity is absent in the glass, the titanium environment is more regular in the vitreous surroundings. Moreover, the modulation in crystalline Ba2TiGe2O8 is responsible for the virtually indiscernible O–K near-edge structures of the glassy and crystalline samples. 相似文献
55.
E. Wolfgang Holla Manfred Schudok Angelika Weber Matthias Zulauf 《Journal of carbohydrate chemistry》2013,32(5):659-663
Abstract In 1988, MOSBACH et aL1 reported the synthesis of a-D-mannopyranosy1-L-serine and Q -D-N-acetylgalactosamino-L-serine by reversing the hydrolytic activity of a -mannosidase from jack beans and a -N-acetylgalactosaminidase from beef liver, respectively. The yields in these equilibrium-controlled syntheses2 using high concentrations of monosaccharide and serine were highly dependent on the enzyme concentration and ranged from 5 to 10 percent in both cases. 相似文献
56.
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Dr. Carlo Fasting Prof. Christoph A. Schalley Dr. Marcus Weber Prof. Oliver Seitz Prof. Stefan Hecht Prof. Beate Koksch Dr. Jens Dernedde Prof. Christina Graf Prof. Ernst‐Walter Knapp Prof. Rainer Haag 《Angewandte Chemie (International ed. in English)》2012,51(42):10472-10498
Multivalent interactions can be applied universally for a targeted strengthening of an interaction between different interfaces or molecules. The binding partners form cooperative, multiple receptor–ligand interactions that are based on individually weak, noncovalent bonds and are thus generally reversible. Hence, multi‐ and polyvalent interactions play a decisive role in biological systems for recognition, adhesion, and signal processes. The scientific and practical realization of this principle will be demonstrated by the development of simple artificial and theoretical models, from natural systems to functional, application‐oriented systems. In a systematic review of scaffold architectures, the underlying effects and control options will be demonstrated, and suggestions will be given for designing effective multivalent binding systems, as well as for polyvalent therapeutics. 相似文献
58.
E. Grell E. Lewitzki C. Bremer S. Kramer-Schmitt J. Weber A. E. Senior 《Journal of fluorescence》1994,4(3):247-250
lin-Benzo-adenine nucleotides can act not only as probes for fluorescence studies but also as structural active site probes for enzymes. To understand the basic properties oflin-benzo-ATP and-ADP, protolysis and Mg2+ and Ca2+, binding are investigated between pH 6.2 and pH 8.5 by spectrophotometric and spectrofluorometric titrations. Based on a reaction model, a set of equilibrium constants is determined which is consistent with all available experimental results. The pK values of the Mg2+ and Ca2+ complex oflin-benzo-ATP in the chosen medium are 4.6 and 4.1, respectively, and those for the corresponding diphosphate are 3.1 and 2.8, respectively. Fluorescence and absorption spectra are reported.This is a peer-reviewed conference proceeding article from the Third Conference on Methods and Applications of Fluorescence Spectroscopy, Prague, Czech Republic, October 18–21, 1993. 相似文献
59.
H. Reuther O. Nikolov S. Kruijer R. A. Brand W. Keune D. Liljequist S. Weber S. Scherrer 《Hyperfine Interactions》1994,92(1):1367-1372
-Fe surfaces were implanted with a nominal dose of 5×1017 Al ions/cm2 at 50 keV and a current density of about 3.7 A/cm2. Samples of different shapes and thicknesses have been used in order to test the influence of heat flow from specimen to target holder during implantation. Integral and energy differential (depth-selective)57Fe conversion electron Mössbauer spectroscopy (CEMS and DCEMS) were employed. The spectra indicated a magnetic phase characterised by a broad hyperfine field distributionP(B
hf), a non-magnetic phase, and -Fe. The relative intensity of the non-magnetic phase was enhanced if the thermal contact during implantation became worse. An energy dependence of DCEM spectra in the L-electron range was observed. Model calculations using L-electron weight functions and experimental concentration profiles obtained by secondary neutral mass spectroscopy (SNMS) yielded fair agreement between calculated and experimental phase signals. The results demonstrate that the non-magnetic Fe-Al alloy phase with high Al concentration is located closer to the surface than the magnetic alloy phase, which extends to much larger depth than expected. 相似文献
60.
We develop large-deviation results with explicit order terms and Cramér's series for nondegenerate U-statistics of degree m under Cramér-type conditions on the kernel. The method of the proof is based on the contraction technique of Keener, Robinson, and Weber [15], which is a natural generalization of the classical method of Cramér [10]. Other techniques used in the proofs include truncation, decoupling inequalities, Borell's inequality for Rademacher chaos, and a partitioning method to bound the degenerate remainder term. 相似文献