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排序方式: 共有10000条查询结果,搜索用时 93 毫秒
991.
Dr. A. N. Danilenko V. Yu. Vetrov A. P. Dmitrochenko A. L. Leontiev E. E. Braudo V. B. Tolstoguzov 《Molecular nutrition & food research》1992,36(2):105-111
Thermodynamic properties of aqueous solutions of both native and modified legumin of broad beans (Vicia faba L.) have been examined. A restricted trypsin-induced proteolysis was used to modify protein structure. Evaluation of protein affinity to ficoll in aqueous solutions showed that modified protein possessed higher hydrophilicity. Thermodynamic properties of diluted solutions were used to predict the phase behaviour in concentrated systems containing protein and ficoll. At specific concentrations of native legumin, the system can separate in two phases, whereas in the case of modified protein the single-phase behaviour of the system was predicted for any concentrations of both components. The experimental data obtained in concentrated systems confirmed predictions of thermodynamic analysis of diluted solutions. 相似文献
992.
Yu. A. Volodin O. F. Glagoleva T. P. Klokova 《Chemistry and Technology of Fuels and Oils》2003,39(4):213-215
Preparation is one method of increasing the efficiency of crude oil feedstock refining processes. In this stage, the feedstock can be activated by regulating the balance of intermolecular interaction forces within a crude oil disperse system by different methods: external fields (electric, magnetic); mechanical; using different kinds of additives, primarily those with surface–active properties. 相似文献
993.
A. A. Vaipolin Yu. A. Nikolaev V. Yu. Rud’ Yu. V. Rud’ E. I. Terukov 《Semiconductors》2003,37(4):414-416
Photosensitive structures of surface-barrier and homojunction types have been fabricated for the first time on the basis of ZnIn2Se4 single crystals. The spectral dependence of the quantum efficiency of photoconversion has been studied and discussed. It is concluded that the structures are promising for commercial applications. 相似文献
994.
图书馆网站设计的探讨 总被引:8,自引:0,他引:8
介绍了当今信息时代建设图书馆网站的重要性和作用 ,以及在网站设计评估中应着重注意的包括网站内容、页面设计及安全性能等三方面的问题 ,同时提出 ,图书馆网站建设中如何在这几方面进行改进和完善。 相似文献
995.
996.
997.
The main problems in estimating the uncertainty due to the presence of impurities in the material: the absence in the documents of a unique definition of the quantity being measured – the fixed point temperature, the lack of agreed methods of realizing the fixed points and the insufficient justification of the equations used for the estimate, are analyzed. The results of a measurement of the melting point of gallium are presented, which differ in the conditions in which they were realized – with one and two liquid-solid interfaces and different solidification conditions, are presented. The reasons for the considerable difference between the values of the temperatures obtained in these experiments are discussed. 相似文献
998.
Progress in the area of fiber-optic sensors throughout the world since 1990 is analyzed. Current technical and market trends as well as the use of sensors in industry and health care are considered. Market forecasts for the use of fiber-optic sensors are given. 相似文献
999.
The possibility of optimum filtration of the radiation of a mercury arc lamp for subterahertz Hilbert-transform spectroscopy with a frequency-selective Josephson detector is demonstrated. Hilbert-transform spectroscopy was used for the first time for measuring the transmission spectrum of a high-pass filter. 相似文献
1000.
V. G. Shengurov S. P. Svetlov V. Yu. Chalkov B. A. Andreev Z. F. Krasil'nik B. Ya. Ber Yu. N. Drozdov 《Inorganic Materials》2003,39(1):3-5
The Ge and Er depth profiles in Si1 – x
Ge
x
layers grown on Si(100) substrates by Si sublimation-source molecular-beam epitaxy in GeH4 were studied by secondary ion mass spectrometry. The results demonstrate that Ge facilitates Er incorporation into the growing Si–Ge layer. The Er dopant profile becomes sharper with increasing Ge content. The Ge profile also has rather sharp boundaries, indicating that there is no Ge surface segregation, which is attributable to the presence of adsorbed hydrogen, acting as a surfactant. 相似文献