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991.
992.
V. L. Balkevich Yu. M. Mosin V. N. Sazhina 《Refractories and Industrial Ceramics》1981,22(7-8):399-402
Conclusions Grainy oxide masses plasticized by aqueous solutions of polymers can be mixed in the mixers used for preparing press powders. This method is not effective in the preparation of finely dispersed masses. The aging of the oxide masses after homogenization serves not only to build up a stock of production material but as a result of aging, the molding properties of the masses are improved and their density increased. Vacuum treatment in plastic molding technology is obligatory. The reduction in the moisture content of the masses after vacuum treatment makes it necessary to adjust the composition of the mass in relation to moisture content. By changing the length of the molding time it is possible to control the relationship between reversible and plastic types of deformation in plastic ceramic masses.Translated from Ogneupory, No. 7, pp. 49–51, July, 1981. 相似文献
993.
In this paper, the process of compact polymer chains escaping from a small sphere to a large one in the view of thermodynamics is investigated in detail based on the pruned-enriched-Rosenbluth method (PERM), which is quite efficient for the three-dimensional polymers on the simple-cubic lattice. In our simulation, three representative states of a polymer chain during the escaping process are studied, and some statistical properties of the chain size and the chain shape, such as mean-square radius of gyration per bond 〈S2〉/N and the shape factor 〈δ∗〉 are investigated. Our aim is to illuminate how the size and shape of the compact chains change during the escaping process. The changes of 〈S2〉/N and 〈δ∗〉 are not monotone and it is due to the fact that the chain should stretch itself in the escaping process. In the meantime, some thermodynamic properties are also calculated here. The hole is designed to be small enough to allow only one monomer at a time and it thus reduces the number of allowed chain conformations and breaks contacts between monomers at the beginning of the process. Additionally, we discuss the free energy barrier per bond H2 − H1 = ΔH of a compact chain, and here H2 is the maximum free energy per bond during the process and H1 is the minimum one when the compact chain is within the small sphere. Averaging free energy barrier over chain length N is convenient for the comparison with different chain lengths. ΔH as a function of chain length N and radius r1 of the small sphere is also studied and our result shows that ΔH for longer chains is lower means that it is relatively easier for each bond in longer chains to surmount the free energy barrier to escape. Some discussions about the self-avoiding walk (SAW) and swollen chains are also made for the comparison, and our results also show that the restriction of the small sphere on the SAW and the swollen chains is more effective because of their relatively looser intrinsic structure. 相似文献
994.
研究了新型含镁络合物的结构、性质及其用于制备高效乙烯聚合催化剂的制备规律。结果表明:将镁、有机醇以及不与镁发生“格式反应”的卤代烷相互作用可迅速发生反应形成新型含镁络合物溶液。该络合物在溶液中可析出结晶。具有特定的化学结构.可以均匀承载于多孔硅胶的孔隙中,负载TiCl4后制备出形态良好的球形高效乙烯集合催化剂。 相似文献
995.
996.
997.
998.
V. A. Bobkov Yu. I. Ron’shin A. P. Kudryashov V. Yu. Mashentsev 《Programming and Computer Software》2014,40(4):159-165
A method of visual navigation by stereoimages for autonomous underwater vehicles is suggested. Two modifications of the method are considered. The first one is based on integration of measurement data of onboard navigation system with visual data. The second modification relies on the use of a six-cloud computation scheme. Results of computational experiments with model data are presented. 相似文献
999.
In manufacturing industries, the quality of a product depends on the combined effect of multiple input variables working singly or together and therefore attention has been given on process capability indices to shift from single to multivariate domain. In case of multivariable domain the capability to incorporate uncertainties at the time of decision making becomes necessary. Fuzzy system is introduced to take care of this requirement. In this article the process parameters of soap manufacturing industries have been analyzed. The process capability is determined using Fuzzy Inference System rule editor based on a set of justified if then statements as applicable for the process. The data has been collected in linguistic form to derive its process capability, using a set of justified rules and the effect of each factor has been determined using Design of Experiments (DoE) and analysis of variance technique (ANOVA) for improving the soap quality from perspective of its softness. This article ventures to propose a new methodology by integrating Fuzzy with DoE providing better result followed by DoE and Fuzzy Inference system in isolation. 相似文献
1000.
I. D. Zborovskii Ya. A. Landa E. Ya. Litovskii Yu. A. Polonskii N. A. Puchkelevich 《Refractories and Industrial Ceramics》1972,13(1-2):18-21
Conclusions An experimental setup was developed for studying the thermal conductivity of refractories up to 2300°C on the hot face of the specimen.In the average temperature range of 500–1800°C a study was made of the thermal conductivity of magnesite refractories of different porosity. The experimental data obtained satisfactorily agree with well-known literature and calculated values for the thermal conductivity coefficients.Translated from Ogneupory, No. 1, pp. 17–21, January, 1972. 相似文献