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61.
J.J. Hauser 《Solid State Communications》1973,13(9):1451-1454
The purpose of this study was to investigate which impurities form localized states in amorphous Ge and to study the concentration dependence of the effect. The low temperature resistivity of amorphous alloy films deposited at 77°K was well fitted by the relation . The increase in the number of localized states resulting from an increase in the number of impurities is evidenced by a decrease in T0 Impurities which lead to shallow energy levels in the crystalline form do not form localized states near the Fermi level while impurities with deep lying levels do. 相似文献
62.
Isidore Fleischer 《Mathematische Annalen》1962,148(5):367-371
Ohne ZusammenfassungM. M. gewidmet 相似文献
63.
We have synthesized two forms of erbium tetracyanoplatinates, Er2[Pt(CN)4]3.21H2O (red form) and Er2[Pt(CN)4]2.SO4.11.5H2O (yellow form), and determined their crystal structures by X-ray diffraction. While the red form crystallizes in the orthorhombic space group Pbcn, with a = 15.4848(3) A, b = 13.8186(2) A, c = 19.07820(10) A, alpha = beta = gamma = 90 degrees, and Z = 4, the yellow form precipitates in the tetragonal space group I4cm, with a = b = 14.321(2) A, c = 13.338(3) A, alpha = beta = gamma = 90 degrees, and Z = 4. Both forms show [Pt(CN)4]2- chains but differ markedly in color and morphology. This is due to the incorporation of sulfate ions in the latter modification, leading to an increased Pt-Pt distance. The observed optical absorption and emission behavior of the title compounds is correlated with the Pt-Pt distances. 相似文献
64.
In conventional fracture-toughness testing, the line of application of the loads remains fixed with respect to specimen geometry. In this testing machine, the load moves with the advancing crack front, and displacement is used as the controlled variable to propagate and arrest a crack. The energy-release rate at the onset of crack propagation and, hence, the plane-strain fracture toughnessK Ic can be measured directly without compliance calibration or stress-intensity evaluation. The specimen is in the form of a flat plat 25 by 50 cm which is simple to machine and provides about 30 values ofK Ic. The versatility of the machine is demonstrated by making a statistical analysis ofK Ic for 7075-T6 Al by showing the effect of plate thickness on the fracture toughnessK c using a tapered specimen, and by evaluatingK c in 7075 Al as a function of aging temperature in a thermal-gradient-treated specimen. 相似文献
65.
Hartmann F. J. Daniel H. Maierl Chr Mühlbauer M. Schott W. Wojciechowski P. Hauser P. Petitjean C. Taqqu D. Kottmann F. Markushin V. E. 《Hyperfine Interactions》1996,101(1):623-632
Two experiments with low-energy muons are described: the determination of the stopping power of C, Si, Ti and Au for muons at energies down to 2 keV and the measurement of the diffusion times for pµ and dµ atoms in low-pressure (0.25–12 hPa) hydrogen gas. A pronounced Barkas effect was found for muons at the Bragg peak (about 10 keV): the stopping power for µ– in C, e.g., is about 30% lower than that for µ+. The mean kinetic energy of pµ atoms at the end of the cascade in 1 hPa hydrogen gas was determined to be (2.6 ± 0.6) eV (preliminary value). 相似文献
66.
Dr. Tiago Rodrigues Nadine Hauser Daniel Reker Dr. Michael Reutlinger Tiffany Wunderlin Dr. Jacques Hamon Dr. Guido Koch Prof. Dr. Gisbert Schneider 《Angewandte Chemie (International ed. in English)》2015,54(5):1551-1555
We report a multi‐objective de novo design study driven by synthetic tractability and aimed at the prioritization of computer‐generated 5‐HT2B receptor ligands with accurately predicted target‐binding affinities. Relying on quantitative bioactivity models we designed and synthesized structurally novel, selective, nanomolar, and ligand‐efficient 5‐HT2B modulators with sustained cell‐based effects. Our results suggest that seamless amalgamation of computational activity prediction and molecular design with microfluidics‐assisted synthesis enables the swift generation of small molecules with the desired polypharmacology. 相似文献
67.
制备了一个苯甲酰腙化合物N'-(2-羟基-5-甲氧基苯甲基)-4-二甲氨基苯甲酰肼(H2L)。利用H2L、乙酰氧肟酸(HAHA)和VO(acac)2在甲醇中反应得到了配合物[VOL(AHA)]。通过元素分析、红外和紫外光谱,以及单晶X-射线衍射对H2L和其配合物进行了表征。苯甲酰腙配体作为二价阴离子,利用其酚羟基氧原子、亚胺基氮原子、以及烯醇氧原子与V原子进行配位。乙酰氧肟酸配体利用其羰基氧原子和去质子化的羟基氧原子进行配位。配合物中的V原子为八面体配位构型。测试了H2L、HAHA和钒配合物的脲酶抑制活性。在浓度为100μmol·L-1时,钒配合物对幽门螺旋杆菌脲酶的抑制率为63%,其IC50值为45μmol·L-1。还利用分子对接技术研究了配合物分子与脲酶的作用方式。 相似文献
68.
Pressure assisted capillary electrophoresis in capillaries with internal diameters of 10 μm was found possible without significant penalty in terms of separation efficiency and sensitivity when using contactless conductivity detection. A sequential injection analysis manifold consisting of a syringe pump and valves was used to impose a hydrodynamic flow in the separation of some inorganic as well as organic cations. It is demonstrated that the approach may be used to optimize analysis time by superimposing a hydrodynamic flow parallel to the electrokinetic motion. It is also possible to improve the separation by using the forced flow to maintain the analytes in the capillary, and thus the separation field, for longer times. The use of the syringe pump allows flexible and precise control of the pressure, so that it is possible to impose pressure steps during the separation. The use of this was demonstrated for the speeding up of late peaks, or forcing repeated passage of the sample plug through the capillary in order to increase separation. 相似文献
69.
F. Horst Müller Ernst A. Hauser Ernst A. Hauser E. Baertich 《Colloid and polymer science》1948,110(2):133-136
Ohne Zusammenfassung 相似文献
70.