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991.
992.
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
993.
I.L. Lehr 《Corrosion Science》2007,49(5):2210-2225
This work is a study of the electropolymerisation of pyrrole onto iron electrodes in the presence of sodium bis(2-ethylhexyl) sulfosuccinate in a wide pH interval. The characterisation of the films was done using electrochemical techniques, SEM/EDX and IR spectroscopy. We show that it is possible to synthesise homogeneous, adherent and very compact films in the pH range between 7 and 12 under potentiodynamic, galvanostatic and potentiostatic conditions without substrate dissolution. The effects of various parameters on electrodeposition were investigated. The new procedure for the electrochemical synthesis of polypyrrole results in improved anticorrosion properties. The inhibition is proposed to be due to the sum of a repulsion of chloride ions because AOT remains entrapped in the polymer matrix and the presence of the iron oxide. Advantages of the use of surfactants in the electropolymerisation solution are discussed. 相似文献
994.
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
995.
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
996.
It is essential to automate the scanning path generation process to effectively implement the micro-stereolithography. However, a scanning path that is generated based only on a 3D CAD model introduces dimensional inaccuracies. In micro-stereolithography, the photopolymer solidification is affected by fabrication conditions, such as the optical properties (laser power, laser scanning speed, laser scanning pitch focusing condition, etc.) and material properties of the photopolymer. Thus, the photopolymer solidification phenomena must be considered when generating a laser scanning path. In this paper, a scanning path generation algorithm that uses 3D CAD data and considers the photopolymer solidification phenomena is proposed to improve the dimensional accuracy in micro-stereolithography. Multi-line photopolymer solidification experiments were performed for various laser scanning conditions to examine the photopolymer solidification phenomena. From these experiments, linear relations between the solidification length (width) and scanning length (width) were acquired and stored in a database. Subsequently, these data were utilized to compensate the scanning path of the laser beam. In addition, experiments for determining the layer thickness in the z-direction were performed and these results were also used in the scanning path generation algorithm.This research was supported by the Highly Advanced National Project (http://www.most.go.kr), which performs some of the National R&D Program, and sponsored by the Korean Ministry of Science and Technology under the contract project code M10214000116-02B1500-02010. 相似文献
997.
This paper discusses an analytical method to study the effects of the vane-parameters on the gain-frequency response of an azimuthally periodic vane-loaded cylindrical waveguide interaction structure for the gyro-traveling wave tube (gyro-TWT) amplifier in the small-orbit TE01 waveguide mode configuration. The vane-loaded gyro-TWT enables the higher gain than that of the smooth-wall device. An optimum choice of the vane dimensions causes a change in the frequency corresponding to the peak-gain. 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.
V. H. Novyts’kyi V. P. Havrylyuk D. D. Panasenko M. O. Kal’chuk V. Ya. Khoruzhyi 《Materials Science》2006,42(6):799-807
The positive influence of lead (2.5%) on the original structure of a cast composite of the Fe-Cr-Cu-C-Ti system, its wear
rate, friction coefficient, and the formation of secondary structures is established under the conditions of dry friction
and friction with boundary lubrication.
__________
Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 42, No. 6, pp. 73–80, November–December, 2006. 相似文献