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991.
A. A. Maksimenko I. D. Sadekov A. G. Maslakov O. E. Kompan A. I. Yanovskii Yu. T. Struchkov V. I. Minkin 《Journal of Structural Chemistry》1991,32(3):404-405
Scientific-Research Institute of Physical and Organic Chemistry, Rostov State University. A. N. Nesmeyanov Institute of Heteroorganic Compounds, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 32, No. 3, pp. 104–106, May–June, 1991. 相似文献
992.
993.
We analyze the analog of the Kelvin-Helmholtz instability on the free surface of a superfluid liquid. This instability is
induced by the relative motion of superfluid and normal components of the same liquid along the surface. The instability threshold
is found to be independent of the value of viscosity, but turns out to be lower than in the absence of dissipation. The result
is similar to that obtained for the interface between two sliding super-fluids (with different mechanisms of dissipation)
and confirmed by the first experimental observation of the Kelvin-Helmholtz instability on the interface between 3He-A and 3He-B by Blaauwgeers et al. (cond-mat/0111343). 相似文献
994.
E. R. Bauminger E. Fibach A. M. Konijn S. Ofer E. A. Rachmilewitz 《Hyperfine Interactions》1991,66(1-4):11-23
Mössbauer studies in murine (MEL) and human K-562 erythroleukemia cell lines have been utilized to study the fate of iron during intracellular Hb synthesis and denaturation. The results showed that ferritin can serve as an intermediate iron pool for Hb synthesis and for storage of iron released during intracellular Hb denaturation. 相似文献
995.
A Green's function technique is developed for describing compositional ordering and vitrification of solid solutions with arbitrary composition. It is shown that the proposed approach is related with the standard theory of ordering of regular solid solutions. Peculiarities of the diagrammatic technique are studied. Explicit expressions are derived for the spectrum of solitary excitations, which are responsible for the ordering. Equations are derived for determining the temperature-concentration dependences of the compositional order parameter, the vitrification parameter, and the chemical potential.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 60–65, May, 1991. 相似文献
996.
997.
H. M. Soroush 《The Journal of the Operational Research Society》1994,45(3):287-300
The classical PERT approach uses the path with the largest expected duration as the critical path to estimate the probability of completing a project by a given deadline. However, in general, such a path is not the ‘most critical’ path and does not provide the smallest estimate for the probability of completion time. This paper studies the ‘most critical path’ problem and formulates it as an optimal path problem in a deterministic network with a two-attribute fractional objective function. An exact solution approach is presented for the optimal path problem which also gives the solution to the most critical path problem. The illustrative examples as well as our computational results demonstrate that the proposed algorithm provides estimates for the probabilities of completion time that are much more accurate than those of the classical approach. 相似文献
998.
V. Ivanova E. Emamilova M. SedlÀK J. PazlarovÀ 《Applied biochemistry and biotechnology》1991,30(2):193-202
Two bacterial α-amylases from new industrial strains were studied: α-amylase fromBacillus amyloliquefaciens CCM 3502 (Czechoslovak) and thermostable α-amylase fromBacillus licheniformis 44MB82 (Bulgarian). The thermostable enzyme hydrolyzed starch mainly to dextrins, and after 1 h, 30% of the products were oligosaccharides. TheB. amyloliquefaciens enzyme produced more maltooligosaccharides than the first enzyme (B. licheniformis). Within 1 h, up to 80% of the substrate were hydrolyzed, giving different spectrum of oligosaccharides in comparison with the thermostable one. 相似文献
999.
A method of identifying low-energy nuclei from the readings of an ionizational mass spectrometer is considered. The identification principles for particles recorded by a multilayer detector are discussed, together with the fundamentals of a probabilistic approach to the solution of this problem. The method permits correct analysis of the experimental data obtained. The determination of the charge and isotopic composition of radiation consisting of a mixture of different nuclei is considered. The results of calculations by the given method which permit the determination of the optimal detector parameters for the solution of the specific physical problem are outlined. This approach is also applicable for the analysis of data from other types of measuring apparatus.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 84–88, July, 1991. 相似文献
1000.
N. Gass 《The Journal of the Operational Research Society》1994,45(2):133-142
A methodology is developed to analyse present and future crisis and conflict potentials of small or large geopolitical regions. A set of criteria is used to describe the present economic, social, political and military conditions of a country and the future criteria trends. A multi-criteria decision analysis model is invoked to compute the crisis and conflict potentials under simultaneous consideration of all other countries in that region. The methodology is demonstrated in the crisis and conflict potentials analysis of the former Soviet republics including bordering countries. 相似文献