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941.
A vibration-acoustic method for diagnostics and monitoring of production processes such as cutting metals makes it possible
compared with other methods to reduce the requirement for measuring equipment and it provides a computer representation of
the results observed. The set of equipment suggested has low cost and it exhibits considerable flexibility compared with existing
equipment.
__________
Translated from Izmeritel’naya Tekhnika, No. 7, pp. 30–34, July, 2006. 相似文献
942.
943.
In the framework of joint effort between the Nuclear Energy Agency (NEA) of OECD, the United States Department of Energy (US DOE), and the Commissariat a l'Energie Atomique (CEA), France a coupled three-dimensional (3D) thermal-hydraulics/neutron kinetics benchmark for VVER-1000 was defined. The benchmark consists of calculation of a pump start-up experiment labelled V1000CT-1 (Phase 1), as well as a vessel mixing experiment and main steam line break (MSLB) transient labelled V1000CT-2 (Phase 2), respectively. The reference nuclear plant is Kozloduy-6 in Bulgaria. The overall objective is to assess computer codes used in the analysis of VVER-1000 reactivity transients. A specific objective is to assess the vessel mixing models used in system codes. Plant data are available for code validation consisting of one experiment of pump start-up (V1000CT-1) and one experiment of steam generator isolation (V1000CT-2). The validated codes can be used to calculate asymmetric MSLB transients involving similar mixing patterns. This paper summarizes a comparison of CATHARE and TRAC-PF1 system code results for V1000CT-1, Exercise 1, which is a full plant point kinetics simulation of a reactor coolant system (RCS) pump start-up experiment. The reference plant data include integral and sector average parameters. The comparison is made from the point of view of vessel mixing and full system simulation. CATHARE used a six-sector multiple 1D vessel thermal-hydraulic model with cross flows and TRAC used a six-sector, 18-channel coarse-mesh 3D vessel model. Good agreement in terms of integral parameters and inter-loop mixing is observed. 相似文献
944.
V. N. Dermanskii N. V. Khmelevtsov R. V. Faizulina O. N. Moleva D. V. Sokhanchuk 《Metallurgist》2007,51(1-2):55-59
The temper-rolling mills in flat-rolled products shop No. 3 at the MMK has been equipped with the Vytyazhka automated system
to measure the elongation of strip (ASEMS) rolled on the mill. The elongation (relative elongation) of the strip is determined
through a frequency-based method of measuring the speed of the strip before and after reduction. The system transmits and
displays information on the temper-rolling of each coil. The information is shown as a diagram on the monitor of an industrial
computer. The reliability of the system allows it to be in continuous use. Introduction of the automated elongation measurement
system makes it possible to monitor the reductions being made during temperrolling, which in turn enables the shop to reduce
the number of products having properties that do not meet customers’ requirements.
__________
Translated from Metallurg, No. 1, pp. 62–63, January, 2007. 相似文献
945.
946.
I. F. Kurunov V. N. Loginov S. S. Lyapin N. S. Polyakov V. N. Titov 《Metallurgist》2007,51(7-8):425-433
The use of schungite as a partial replacement for coke is practiced in Russia at a number of metallurgical plants, both in
the production of foundry iron (its primary use) and in making conversion pig iron. The largest amount of coke is replaced
when foundry iron is being made, the replacement coefficient in this case having a value within the range 0.8–1.3. Studies
that included continuous monitoring of the temperature of the carbon blocks in blast furnaces with volumes of 1719, 3200,
and 5580 m3 unambiguously demonstrate that the thickness of the slag crust in blast furnaces increases with the use of schungite. Protecting
the lining of the hearth through the use of schungite is also accompanied by a decrease in coke consumption.
__________
Translated from Metallurg, No. 8, pp. 53–57, August, 2007. 相似文献
947.
N. E. Esipova E. V. Blinov T. G. Movchan I. O. Bannykh 《Russian Metallurgy (Metally)》2007,(2):148-152
The corrosion resistance of the convex and concave sides of bent plates from a high-nitrogen non-magnetic steel has been studied in aqueous solutions of sulfuric and hydrochloric acids. Weighing and hydrogen methods are used to control the corrosion rate of bent-sample sides and to find a number of effects that complement the picture of the stress corrosion of iron alloys and support the existence of the mechanochemical deformation sign effect. 相似文献
948.
Radioimmunoassay was employed to examine distribution of antigenic structures of bovine serum albumin (BSA), absorbed by the gastrointestinal tract, in the blood serum and organs of intact rats. It was shown that 3 h after administering 3H-BSA an appreciable amount of its antigenic structures could be identified in the blood serum, liver, spleen, and carcass of the animals. The total amount of antigenic determinants of BSA which got into the internal environment of the body from the intestine amounted to about 0.2% of the dose administered. The highest specific content of antigenic structures of BSA supplied via the intestinal barrier was detected in the spleen. 相似文献
949.
The manometric technique was employed to study the initiated oxidation of 7 samples of whitefish lipids of varying sites, to measure the kinetic parameters depending on the fatty acid composition and concentration of tocopherol. Changes in oxidative stability of lipids of varying localization was shown, a higher stability of muscle tissue lipids was noted as compared with brain and depot lipids. The possibility of testing oxidative stability of lipids according to the kinetic parameters is discussed. 相似文献
950.
D.R Hayhurst D.A Lavender N.G Worley A Salim 《International Journal of Pressure Vessels and Piping》1985,20(4):289-317
Constant stress creep data for a wrought 1%Cr, , steel obtained from six tests carried out at 565°C have been fitted and extrapolated using the θ-projection method. Creep curves for high stresses were fitted well, but curves extrapolated to stress levels below those used in the θ-projection did not represent well the available data for primary-secondary creep. To enable a satisfactory extrapolation of results, it was found necessary to redefine the failure condition to be less sensitive to the shape of the latter sections of the tertiary creep curve. This was achieved by defining lifetime as the point on the curve at which the strain rate reached a fixed multiple of the creep rate at half the rupture time. The extrapolated data compare well with the results of tests carried out independently on a cast 1%Cr, , steel. The extrapolation procedure not only predicts the ‘knee’ in the log stress-log lifetime curve but allows extrapolation of lifetimes by over a factor of thirty. In addition, acceptable predictions have been made of constant load experimental data. 相似文献