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991.
V. D. Belik R. V. Litvin M. S. Koval’chenko 《Powder Metallurgy and Metal Ceramics》2006,45(11-12):593-598
The influence exerted by electric-spark spraying on the kinetics of mass transfer and the physicomechanical properties of coatings is investigated. It is shown that electric-spark spraying is determined by the dynamic properties of the cathode jets, which depend on the electrical parameters of the spark discharge, the size of the interelectrode interval, and the physical properties of the coatings, which vary during spraying. 相似文献
992.
Kanda Runapongsa Jignesh M. Patel H.V. Jagadish Yun Chen Shurug Al-Khalifa 《Information Systems》2006
We propose a micro-benchmark for XML data management to aid engineers in designing improved XML processing engines. This benchmark is inherently different from application-level benchmarks, which are designed to help users choose between alternative products. We primarily attempt to capture the rich variety of data structures and distributions possible in XML, and to isolate their effects, without imitating any particular application. The benchmark specifies a single data set against which carefully specified queries can be used to evaluate system performance for XML data with various characteristics. 相似文献
993.
V. G. Kashakashvili S. Ya. Kurashvili A. G. Gordeziani A. N. Gagnidze 《Metallurgist》2006,50(1-2):36-38
A unit for making L-class high-strength pump-compressor tubing composed of low-carbon, low-alloy steels of type 15GFB is now
being used on the 140 mill in the tube-rolling shop at the Rustavi Metallurgical Plant. The steel 15GFB pump-compressor tubing
made by the technology that was developed has the following service properties: σy = 630–670 N/mm2, σu = 730–780 N/mm2, δ = 18–22%, ψ = 55–60%, KCU = 1.6–2.2 MJ/m2. The percentage of ductile fracture at room temperature is 85–95%.
__________
Translated from Metallurg, No. 1, pp. 79–80, January, 2006. 相似文献
994.
The possibility of obtaining chemically stable ceramics in plastic molding from pastes based on comprehensive use of mining
by-products (plagioporphyry, quartz-biotite shale), alumina production wastes (red mud), and polymineral clay was demonstrated.
The mechanism of enhancing paste sintering on addition of finely disperse grog-flux and increasing the alkali resistance of
the material (to 95%) in molding of the crystalline hematite-anorthite-quartz system was examined.
__________
Translated from Steklo i Keramika, No. 2, pp. 17–20, February, 2007. 相似文献
995.
996.
I N Trubachev Iu N Okladnikov V A Barashkov G S Kalacheva N A Tabakov 《Voprosy pitaniia》1985,(1):55-57
The authors studied the biochemical composition of the meat of broilers, eggs, liver and muscles of laying hens of 3 generations on a 5, 10, 25, 50 and 100% (broilers), 10 and 20% (laying hens) replacement of the animal protein quota in the diet by protein obtained from the hydrogen bacteria Alcaligenes eutrophus L-1. No deterioration of the quality of the produce was found from the standpoint of the main biochemical parameters. 相似文献
997.
This paper presents a new model to study the reliability of communication networks in which link failures are statistically dependent. The approach tries to identify and model explicitly the events that cause communication link failures. No conditional probabilities are needed, and so two major difficulties inherent to them, namely, an exponential number of conditional probabilities to deal with and a consistency requirement to satisfy, are avoided. For reliability computations, some existing algorithms for finding network reliability can be used with minor modifications and no significant increase in computational complexity. 相似文献
998.
V. J. Cid A. M. Alvarez A. I. Santos C. Nombela M. Sanchez 《Yeast (Chichester, England)》1994,10(6):747-756
Yeast exo-1,3-β-glucanases are secretable proteins whose function is basically trophic and may also be involved in cell wall glucan hydrolytic processes. Since fluorescein di(β-D -glucopyranoside) is a fluorogenic substrate detectable and quantifiable by flow cytometry, it was used for testing the ability of the EXG1 gene product of Saccharomyces cerevisiae and its homologous gene in Candida albicans to function as reporter genes. These open reading frames were coupled to different promoters in multicopy plasmids, and exoglucanase activity quantified at flow cytometry. Exoglucanases were found to be useful tools for the study of promoter regions in S. cerevisiae. This technique has the advantage over other reporter gene systems—such as β-galactosidase fusions—that it does not require permeabilization of yeast cells and therefore it allows the recovery of viable cells—by sorting—after flow cytometry analysis. 相似文献
999.
É. V. Antonenko 《Strength of Materials》1994,26(7):539-545
Stiffness criteria are proposed for circular frames in problems of the stress-strain state of thin-walled cylindrical structural orthotropic shells. On the basis of the results of a computation experiment and actual test data the author establishes limiting values for stiffness criteria with which frames may be assumed to be absolutely stiff or absolutely compliant for a given shell. It is shown that for frames in the case of axisymmetric strains it is necessary to consider elasticity and that it is possible to use the idea of an absolutely stiff frame with nonaxisymmetric shell strains.Translated from Problemy Prochnosti, No. 7, pp. 76–83, July, 1994. 相似文献
1000.
V. G. Patrikeev A. D. Kozlov Yu. V. Mamonov Sun' Yan-Tszo 《Measurement Techniques》1994,37(5):535-538
Means are considered for reducing the systematic errors in calculating the flow rate of material. For operative monitoring of the day- to- day flow rate, a comparative analysis is made of the numerical solution of the mass flow rate equation and the structure- generalized method for solving the equation.Translated from Izmeritel'naya Tekhnika, No. 5, pp. 37–39, May, 1994. 相似文献