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991.
992.
L. B. Khoroshavin D. S. Rutman V. A. Perepelitsyn V. I. Popova Ya. G. Gaponov K. V. Simonov I. Ya. Makogon N. F. Kravtsov L. M. Polyakov E. I. Tyurin N. P. Tyutyunik M. I. Grigorenko V. A. Tambovtsev A. V. Safonov L. A. D'yakonova I. V. Zhukov 《Refractories and Industrial Ceramics》1982,23(7-8):340-346
Conclusions A method has been developed for production of standard periclase-chromite concrete parts for the linings of high temperature ladles for teeming steel and ferroalloys. The parts have high strength and low porosity and are practically shrinkage-free.The life of periclase-chromite concrete parts in the steel teeming ladles of Chelyabinsk Metallurgical Plant is about four times greater than that of fireclay parts, in Red October Plant practically the same as that observed with the use of high alumina parts, and at Chelyabinsk Electrometallurgical Plant it was higher only in the upper portion of ladles in comparison with that obtained with the normally used fired periclase parts.During service in ladles the parts do not spall, become encrusted at a metal temperature of 1620 °C, do not become encrusted at 1790°C, and at 2200°C are eroded by slag.Translated from Ogneupory, No. 7, pp. 16–20, July, 1982. 相似文献
993.
Akimov G. Ya. Prokhorov I. Yu. Timchenko V. M. 《Refractories and Industrial Ceramics》2002,43(3-4):100-102
The effect of quasi-hydrostatic compression on the strength of ZrO2 + 3 mol.% Y2O3 ceramic specimens of two series was studied. The series 1 ceramic was a powder commercially available from TOSOH Co. (Japan), with a density of 6.1 g/cm3, and the series 2 ceramic was a powder with a density of 5.9 g/cm3 prepared under laboratory conditions at the IPM Research Institute (National Academy of Sciences, Ukraine). The pressure range was up to 1.2 GPa, and the pressure-transmitting medium was a coarse-grained corundum powder. In the series 1 specimens, the strength increases with pressure over the entire pressure range (from 670 MPa to 1098 MPa at 1.2 GPa); in the series 2 specimens, the strength increases only to a pressure of 0.8 GPa (from 695 MPa to 828 MPa) and then, with further increase in pressure drops sharply to nearly zero (30 MPa at 1.2 GPa). It was proposed that the observed effect might be associated with a martensite transformation in the zone of structural imperfections (discontinuities). On reaching a critical value determined by the strength of the matrix, the martensite transformation becomes a cause of failure of the material. 相似文献
994.
A new aromatic diamine monomer containing benzoxazole substituents was prepared by a multistep synthesis starting from 1,4‐dibromo‐2,5‐difluorobenzene. The diamine was polymerized with commercial aromatic dianhydride or dicarboxylic acid chloride monomers to provide several different poly(amic acid)s and polyamides with their inherent viscosities in the range of 0.24–0.46 dL/g. Thermal properties of these polymers including thermal imidization of poly(amic acid)s into polyimides were investigated by using FTIR, DSC, and TGA. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 178–185, 2004 相似文献
995.
996.
远红外丙纶的性能研究 总被引:7,自引:2,他引:7
系统测试了采用共混纺丝法研制出的远红外丙纶及织物的物理机械性能、远红外发射性能、保温性能、耐洗涤性能和抗菌性能,并对用远红外丙纶加工的护腿的医疗保健作用进行了临床检测。进而讨论了远红外丙纶及织物的医疗保健作用机理。 相似文献
997.
998.
S. A. Suvorov A. D. Mel'nikov V. A. Orlov K. V. Simonov L. D. Bocharov G. I. Kuznetsov V. A. Perepelitsyn L. Ya. Pivnik 《Refractories and Industrial Ceramics》1980,21(3-4):145-153
Conclusions The processes of wear in the lining of vacuum chambers of outdoor-furnace vacuum-treatment plants (UPVS) are due to the simultaneous action of high temperatures, deep vacuum, gaseous medium, molten metal, and slag. The corrosion and erosion of aggressive melts of slag and metal are the decisive forms of wear.Laboratory investigations established the relationship between slag resistance in vacuum and the ratio of corrosive and erosive constituents in the wear of different magnesia-spinel refractories and their phase composition, structure, and properties.Refractories obtained from fused periclase-chromite material with a low content of fusible silicates showed that in laboratory vacuum equipment and during service in the linings of the vaccum chamber of industrial plant they have higher slag resistance and lower wear than refractories based on sintered magnesite, spinel, and chromite ores.Translated from Ogneupory, No. 3, pp. 14–21, March, 1980. 相似文献
999.
Conclusions Temperature functions were obtained for H(T) and Cp(T) which can be used for calculating the thermodynamic functions of the spinels MgAl2O4 and MgCr2O4 in the temperature regions of their service (up to 2200°K), to supplement the existing relationships (up to 1800°K).Translated from Ogneupory, No. 6, pp. 9–12, June, 1979. 相似文献
1000.