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141.
Ohne Zusammenfassung 相似文献
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Attard P 《The Journal of chemical physics》2005,122(15):154101
The concept of second entropy is introduced for the dynamic transitions between macrostates. It is used to develop a theory for fluctuations in velocity, and is exemplified by deriving Onsager reciprocal relations for Brownian motion. The cases of free, driven, and pinned Brownian particles are treated in turn, and Stokes' law is derived. The second entropy analysis is applied to the general case of thermodynamic fluctuations, and the Onsager reciprocal relations for these are derived using the method. The Green-Kubo formulas for the transport coefficients emerge from the analysis, as do Langevin dynamics. 相似文献
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High densities of electron-hole plasma have been optically injected into Ge at T ∼ 2K, and the plasma density inferred from measurements of the plasma absorption at 3.39μ. The behavior of the conductivity with increasing density and at different electric fields can be understood from a model of a plasma condensation into high density drops, with the plasma density in the drops ? 6 × 1016 c−3. 相似文献
148.
Phil Won Yu 《Solid State Communications》1978,27(12):1421-1424
Compensation ratios in high purity epitaxial GaAs layers are determined by Nam et al.'s photoluminescence method at a well-defined finite excitation intensity. This excitation intensity is obtained from the excitation-dependence of the peak energy of the neutral donor-acceptor transition. The values of compensation ratio determined in this way are in excellent agreement with those obtained by the conventional electrical method. 相似文献
149.
Hydrolytic oxidation of organosilanes to the corresponding silanols can be performed highly efficiently with a catalyst system of [IrCl(C(8)H(12))](2) under essentially neutral and mild conditions, and various types of silanols are produced in good to excellent yields. 相似文献
150.
This paper describes highly efficient allyl cross-coupling reactions of allylindiums with organic electrophiles such as aryl and vinyl triflates, vinyl halides, dibromoolefin, and alkynyl iodide. The reactions were carried out using 4 mol % Pd(PPh3)4 in the presence of 3 equiv of LiCl in DMF at 100 degrees C under a nitrogen atmosphere. Allylindium, generated from the reaction of 1 equiv of indium with 1.5 equiv of allyl halide, gave the best result as a coupling partner. The present method is mild and simple to apply, and it produces a diverse range of allylic compounds in good to excellent yields. 相似文献