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991.
E. A. Garber I. A. Kozhevnikova P. A. Tarasov A. A. Zavrazhnov A. I. Traino 《Russian Metallurgy (Metally)》2007,(2):112-119
A new procedure for the calculation of contact stresses and hot-rolling forces for wide strips 0.8–1.5 mm thick has been developed and tested. This procedure takes into account the presence of a stick zone in the deformation zone and stress distributions in both elastic and plastic regions in the deformation zone. The average error in the force calculation according to the new procedure is 5%, which is more than two times smaller than the calculation error of well-known force calculation procedures. The developed procedure is used to simulate the contact stresses in the deformation zones of working stands in a six-stand 1700 mill during rolling of strips thinner than 1.0 mm. A number of new relations for the state of stress in a strip have been revealed upon simulation. Some of these relations are as follows: in the last stands, the length of elastic regions accounts for 10–17% of the total deformation-zone length; the maximum normal contact stresses are 1300–1400 MPa, which corresponds to the stresses in the deformation zones of cold-rolling mills; the stick-zone length accounts for 85–99% of the deformation-zone length; and the contact stresses in the stick zone are virtually independent of the friction coefficient. The developed calculation procedure can be used to optimize the technological regimes of wide-strip mills. 相似文献
992.
Analytical solution of a system of nonlinear measuring equations of a 12-pole microwave reflectometer was obtained. Criteria for selecting a true solution in the general case were developed and the analysis was conducted for a number of particular cases that may generate practical interest. 相似文献
993.
The folacin activities in fresh Swiss chard leaves stored in open air at 4, 21, 35 and 40°C were determined by a microbiological assay using Lactobacillus casei. At 21°C the leaves were also stored in plastic bags and under moist conditions. Folacin was most stable when the vegetable was stored in plastic bags, followed by the moist condition, and least stable in open air at 21°C. The degradation of folacin in Swiss chard under all conditions followed firstorder kinetics. The temperature dependent folate degradation conformed to the Arrhenius equation and the activation energy was 24 kcal/mole. 相似文献
994.
995.
V. E. Alekhin I. P. Miroshnichenko V. P. Sizov 《Russian Journal of Nondestructive Testing》2007,43(2):113-118
A mathematical model and the results of the numerically simulated procedures of measuring displacements of tested objects’ surfaces with the use of laser interferometers are presented. Promising measurement techniques are substantiated, and recommendations for their use are given. 相似文献
996.
I. V. Gervas’eva D. P. Rodionov Yu. V. Khlebnikova N. F. Vil’danova A. S. Shtyrlov G. A. Dosovitskii A. R. Kaul’ 《The Physics of Metals and Metallography》2007,103(6):600-608
The texture, structure, and magnetic and mechanical properties of thin ribbons of nickel-palladium alloys have been studied. It has been demonstrated that in Ni94Pd6 and Ni92.5Pd5W2.5 alloys, a sharp cube texture can be formed that is stable up to rather high annealing temperatures. Segregation of palladium atoms to surface layers of ribbons has been found, which gives additional advantages for using these ribbons as substrates for epitaxial deposition of high-temperature superconductors. 相似文献
997.
B. S. Bokshtein D. V. Vaganov S. N. Zhevnenko 《The Physics of Metals and Metallography》2007,104(6):564-570
Surface tension of pure copper and its alloys with Sn has been measured at 1000°C in a hydrogen atmosphere. Surface tension of a free surface equaled 1.81 N/m for pure copper, and 1.55, 1.38, and 1.28 N/m for the alloys with 0.05, 0.22, and 0.33 at % Sn, respectively; surface tension at grain boundaries equaled 0.5 N/m for pure copper, and 0.36, 0.3, and 0.23 N/m for the alloys, respectively. Based on these data, the concentration dependence of tin absorption at a free surface and grain boundaries has been calculated. Parameters of Sn absorption at grain boundaries and a free surface of copper have been compared with those of Sb and Bi. 相似文献
998.
E. S. Gorkunov S. Yu. Mitropol’skaya A. M. Povolotskaya 《Russian Journal of Nondestructive Testing》2005,41(3):175-181
Stacks of steel plates having different values of magnetic hardness and separated with nonferromagnetic gaps are investigated. The coercive force and the residual magnetic induction of a stack measured in a closed magnetic circuit depend on the layout of the plates in the stack and on the thickness of nonmagnetic gaps between them.__________Translated from Defektoskopiya, Vol. 41, No. 3, 2005, pp. 55–62.Original Russian Text Copyright © 2005 by Gorkunov, Mitropol’skaya, Povolotskaya.Dedicated to the Anniversary of the 100th Birthday of Corresponding Member of the Russian Academy of Sciences M. N. Mikheev 相似文献
999.
V. F. Matyuk M. A. Mel’gui D. A. Pinchukov A. L. Lyubarets 《Russian Journal of Nondestructive Testing》2005,41(5):269-276
Results of an experimental study of the anomalous behavior of the residual-magnetization hysteresis of ferromagnetic articles that, under local magnetization and magnetization reversal in a pulsed magnetic field with a variable amplitude, were subjected to heat treatment under different conditions are reported. Parameters of the hysteresis and their dependence on the magnetization and magnetization-reversal conditions, as well as on the magnetic properties of a material, are considered.__________Translated from Defektoskopiya, Vol. 41, No. 5, 2005, pp. 3–13.Original Russian Text Copyright © 2005 by Matyuk, Mel’gui, Pinchukov, Lyubarets.All papers in this issue are devoted to the 100th anniversary of the birth of the late M.N. Mikheev, corresponding member of the Russian Academy of Sciences and one of the founders of magnetic structural analysis. 相似文献
1000.
R. Dinesh T. Fujiwara T. Watanabe K. Byrappa M. Yoshimura 《Journal of Materials Science》2006,41(5):1541-1546
A well-crystallized AMO4 (A=Ba, Ca, Sr; M=W, Mo) films have been prepared at room temperature through a simple solution reaction in respective alkaline
solution at higher pH ranging from 12–14. Adopting the corrosion principle for oxidation of metal substrate, these double
oxide films were carried out in presence of chemical driving force without any special apparatus or devices. Hydrogen peroxide
was used to enhance the dissolution rate of metal substrates. The driving force for the film formation and growth were high
concentration of A2+, MO42− ions with high pH conditions. Average grain sizes of 8–10 μm with bipyramidal shaped particle were grown to the thickness
of about 10–14 μm after 3–6 hours treatment. The crystallization of AMO4 was characterized by three-dimensional nucleation. This work demonstrates the possibility of fabrication of functional ceramic
films directly from the aqueous solution in a single step by solution reactions. 相似文献