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21.
Lysine may be determined in protein hydrolyzates with the aid of lysine decarboxylase contained in cell-free extracts of Salmonella hadar grown under suitable conditions. 相似文献
22.
Dvora Barnea Ovadia Shoham Yehuda Taitel 《International Journal of Multiphase Flow》1980,6(5):387-397
An improved system of conductance probes is used to identify the flow patterns in two phase horizontal, near horizontal and upward flows. The results show that this system is very well suited to distinguish among flow patterns consistent with visual observations. 相似文献
23.
Yehuda Pinchover 《Journal of Functional Analysis》2004,206(1):191-209
In this paper we study the large time behavior of the (minimal) heat kernel kPM(x,y,t) of a general time-independent parabolic operator Lu=ut+P(x,∂x)u which is defined on a noncompact manifold M. More precisely, we prove that
24.
Yehuda Partom 《International Journal of Non》1966,1(4):283-289
A numerical scheme for correlating any two finite strain measures is given, and situations in which such a scheme might be used are introduced. A check is established by comparison with the Reiner-Hanin solution of the Almansi-to-Hencky conversion. A numerical example is provided. 相似文献
25.
V. F. Dovganyuk V. Z. Sharf V. K. Belyaeva I. N. Marov Zh. L. Dykh L. I. Lafer V. I. Yakerson 《Russian Chemical Bulletin》1990,39(2):217-221
Heterogenized catalysts based on rhodium complexes attached to polymers modified by the groups 3(5)-methylpyrazole, imidazole and benzimidazole have been synthesized. The process of their formation has been investigated by IR, UV, and EPR spectroscopy. Results have been obtained for the catalytic activity of the complexes in the hydrogenation of nitrobenzene by hydrogen transfer from propan-2-ol and NaBH4.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, pp. 268–273, February, 1990. 相似文献
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27.
Lon J. Mathias Peter D. Livant Sharf U. Ahmed 《Journal of polymer science. Part A, Polymer chemistry》1987,25(10):2711-2716
Several new copolymers have been synthesized. Initial polycondensation of mixtures of aryl and arylalkyl carboxylic acids containing aromatic hydroxyl and amine substituents led to random copolyamides. Thermal cyclization of these prepolymers (inherent viscosities of about 0.2 dL/g) gave copolybenzoxazoles with inherent viscosities of about 1.4 dL/g. Thermal stability as measured by TGA was similar for the 1:1 copolymers and the homopolymers containing hydrocinnamic units; i.e., catastrophic decomposition occurred at 450°C. Copolymers with lower ratios of the hydrocinnamic units displayed greatly improved thermal stability while maintaining good molecular weight. 相似文献
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29.
Reliable measurements of the sublimation rate of nonuniform layers of trinitrotoluene (TNT) microcrystals were carried out using a quartz crystal microbalance (QCM). The sample layer was prepared by precipitation of TNT from a well-defined volume of its solution in acetonitrile. The TNT solution was placed on the QCM electrode surface to form the precipitated layer of TNT microcrystals. It is shown that the kinetics of small TNT particles sublimation is controlled by the molecular diffusion in air. The sublimation process is well described by simple diffusion expressions that are discussed in the literature for both individual hemispherical-shaped microcrystals and disk-shaped layers. Expressions describing particle size evolution in time were derived based on this diffusion model. It is shown that the expressions developed can be used to simulate particle sublimation in a wide size range, including very small sub-micrometer particles. 相似文献
30.
An extension of the product operator formalism of NMR is introduced, which uses the Hadamard matrix product to describe many simple spin 1/2 relaxation processes. The utility of this formalism is illustrated by deriving NMR gradient-diffusion experiments to simulate several decoherence models of interest in quantum information processing, along with their Lindblad and Kraus representations. 相似文献