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91.
V. M. Efimov A. L. Reznik A. V. Torgov A. A. Solov’ev 《Pattern Recognition and Image Analysis》2011,21(2):176-178
The possibilities of the application of a linear distortion compensation algorithm in solving the systems of linear algebraic
equations with band matrices are considered. The relationships required for the step-by-step solution procedure are derived,
and the conditions of their correct application are determined. 相似文献
92.
93.
Viktor Dukhovny 《国际水》2013,38(4):530-531
Abstract A hydrogeological and microbiological study was carried out in Italy in order to verify the effectiveness of a DRASTIC-based method for groundwater vulnerability assessment in carbonate (fractured-karstified) aquifers. The research was developed: (a) by the monitoring of microbial contamination of two springs from January to July 2001 and from December 2002 to March 2003; and (b) by column tests in intact soil blocks, utilizing a collection strain of Enterococcus faecalis. The comparison of the vulnerability map with the results of the microbiological experiments demonstrated the effectiveness of the new DRASTIC-based method as a predictor of groundwater microbial contamination in carbonate aquifers. The effectiveness of the new proposed approach was verified and highlights the diversified role of the diffuse infiltration of precipitations through the fracture pattern and the more or less concentrated infiltration of surface water in karst areas. 相似文献
94.
G. A. Efimov L. V. Kozlovskii V. I. Moskalev N. R. Okuneva G. V. Smirnov N. V. Suchkova V. I. Shtank'ko 《Glass and Ceramics》1990,47(6):222-224
Translated from Steklo i Keramika, No. 6, pp. 21–22, June, 1990. 相似文献
95.
It has been observed that the texture axis of graphite-like boron nitride is reoriented by recrystallization under pressure. The observed effect is due to the compression conditions for the anisotropic phase deviating from hydrostatic. 相似文献
96.
Anja Car Chrtomir Stropnik Wilfredo Yave Klaus‐Viktor Peinemann 《Advanced functional materials》2008,18(18):2815-2823
This paper reports the design of a tailor made polymeric membrane by using poly(ethylene oxide)–poly(butylene terephthalate) (PEO‐PBT) multi‐block copolymers. Their properties are controlled by the fraction of the PEO phase and its molecular weight. To explain the effect of structural changes in copolymer membranes, transport properties of four gases (CO2, H2, N2, and CH4) are discussed. After characterization, the two best copolymers are selected in order to prepare tailor made blends by adding poly(ethylene glycol) (PEG). The best selected copolymer that contained 55 wt. % of 4000 g mol−1 PEO produced a blend with high CO2 permeability (∼190 barrer), which is twice the permeability of the pure copolymer. At the same time, an enhancement of CO2/H2 selectivity is observed (∼13). These results suggest that the morphology of PEO‐PBT can be well controlled by the addition of low‐molecular‐weight PEG, and consequently the gas transport properties can be tuned. 相似文献
97.
During the past 20 years, biologists have become used to finding that proteins first identified in simple, genetically manipulable eukaryotic organisms are conserved in higher eukaryotes. This article draws attention to the similarity between NUDF protein, which is required for nuclear migration in the filamentous fungus Aspergillus nidulans, and a mammalian homologue, LIS1, whose malfunction causes lissencephaly, a neuronal migration disease. The authors suggest that there might be an underlying similarity of mechanism between nuclear migration in the fungus and neuronal migration in the brain. 相似文献
98.
A. G. Vikhman M. A. Kharichko V. Ya. Kievskii V. A. Efimov I. Yu. Enukova S. V. Osipov M. I. Aminev B. G. Levchenko 《Chemistry and Technology of Fuels and Oils》2005,41(5):370-379
Refining of heavy crudes and to an even greater degree, stiffening of the environmental requirements for the sulfur content
in petroleum products and sulfur compounds in gaseous emissions into the atmosphere make the problem of process and technical
improvement in active elemental sulfur production units (ESU) in oil refineries very pressing. These units are in the first
10 of the 30 environmentally most hazardous basic processes in refining of hydrocarbon feedstock [1].
__________
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 5, pp. 27 – 31, September – October, 2005. 相似文献
99.
The low-cycle strength and cyclic creep, structural changes and the nature of failure for molybdenum-tungsten alloy of the system Mo – 30%W – NbC – C prepared by powder metallurgy at 1770, 2020, and 2270 K are studied. At these temperatures a single dependence for the steady-state cyclic creep rate on the ratio of the equivalent stress to the material yield point at the corresponding temperature and a generalized low-cycle strength curve for the alloy are obtained. It is shown that the cyclic nature of the applied load accelerates directional plastic deformation and failure of powder metallurgy alloy by a factor from 1.5 to 7 compared with prolonged static loading with retention of similarity for the cyclic and static creep curves. At these temperatures the alloy essentially fails as a result of the occurrence of a critical polygonization stage. The structural changes found are in complete conformity with previously predicted features of this mechanism. Under nonstationary loading conditions the incubation period of the critical polygonization stage is shorter, which results in acceleration of creep compared with testing under stationary conditions. 相似文献
100.
Shevchenko Alexey V. Dudnik Elena V. Ruban Alexey K. Red'ko Viktor P. Lopato Lidiya M. 《Powder Metallurgy and Metal Ceramics》2002,41(11-12):558-563
An 80 mass% ZrO2 ― 20 mass% Al2O3 powder was produced using a complex method which integrates sol-gel technology and hydrothermal synthesis. The specific surface areas of the powder varied from 39 to 5.3 m2/g depending on the thermal treatment conditions. Metastable F-ZrO2 formed after powder annealing at 400°C. The phase transformation F-ZrO2 → T-ZrO2 (traces of M-ZrO2) occurred under powder thermal treatment from 700 to 1000°C. Only Θ-Al2O3 was detected under experimental conditions. The powder was characterized by sintering activity. Operating the processes under powder thermal treatment in the ZrO2 ― Y2O3 ― CeO2 ― Al2O3 system will allow one to produce a variety of ceramic microstructures from fine-grained to “self-reinforced.” These powders can be used in manufacturing surgical cutting tools as well as in ceramic passive bioimplants and solid electrolytes for fuel elements. 相似文献