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81.
Yu. E. Pivinskii P. V. Dyakin Ya. Yu. Pivinskii S. V. Vikhman 《Refractories and Industrial Ceramics》2003,44(5):309-313
General aspects (including terminology) related to the use of ultradisperse particulates (nanosystems) are discussed. The important role of nanoparticles in the technology of highly concentrated binding suspensions (HCBS) and refractory castables is emphasized. Using nanoparticles provides a route toward improving the rheotechnologic properties of HCBS and HCBS-based molding mixtures as well as the structure and service properties of the end product. 相似文献
82.
I. Yu. Grebennikov V. I. Gun’ko A. Ya. Dmitrishin L. I. Onishchenko S. O. Toporov T. A. Feshchuk 《Russian Electrical Engineering》2007,78(1):23-25
Methods for cleaning commercial T-1500 dielectric oil with different adsorbents are studied. The oil is intended for impregnation of high-voltage pulse capacitors with film dielectric. 相似文献
83.
In the present work, the Hopfield neural network model with infinite-range interactions was simulated by using the Wang-Landau algorithm. All simulations and measurements were done in the replica symmetric and broken regions of the model with discrete ?1 values of random variables. The physical quantities such as energy density, specific heat were evaluated at all temperatures. Our results are in good agreement with the replica symmetric mean field solutions. 相似文献
84.
Ya. F. Lomnitska 《Powder Metallurgy and Metal Ceramics》2007,46(9-10):461-466
The interaction of components in the V-Si-Sb system is examined at 0.7 mole% Sb using an x-ray analysis. An isothermal section of the phase diagram is constructed at 1070 K. The existence of V4SiSb2 with the W5Si3-type structure is not confirmed. Based on VSi2 (CrSi2 structure type), V5Si3 (W5Si3), VSb2 (CuAl2), VSb (NiAs) compounds, terminal solid solutions are formed. Their solubility is lower than 0.05 mole% of the third component. A continuous series of solid solutions exists between V3Si and V3Sb (Cr3Si). The interaction of components in related systems is analyzed. 相似文献
85.
For the system with a small parameter under nonlinearities, consideration was given to the problem of optimal speed. The values of the multivariable control actions are bounded in the Euclidean norm. The theorem of existence and asymptotic properties of the solution of this problem was proved. It underlies the algorithm to construct asymptotic arbitrary-order approximations to the optimal control. 相似文献
86.
S.B. Burson D. Bradley J. Brockmann E. Copus D. Powers G. Greene C. Alexander 《Nuclear Engineering and Design》1989,115(2-3)
The NRC's Research Program on Core-Debris/Cavity Interactions comprises two principal elements: (1) an analytical effort focused primarily on development of computer codes needed to predict the potential consequences of risk-significant severe-accident scenarios; and (2) an experimental component to provide insights into the relevant phenomenological processes and to develop the experimental data base necessary for validation of the codes. The analytical activities at Sandia National Laboratories (SNL) focus primarily on refinement and validation of the CORCON and VANESA codes. Two major experimental activities are also based at SNL: (1) the large-scale SURC tests address the thermal-hydraulic phenomena in the cavity as well as aerosol release associated with prototypical core-melt materials in various types of concrete crucibles, while (2) the WITCH and GHOST experiments are concerned with aerosol generation and radionuclide release phenomena. A program of small-scale special-effects tests at Brookhaven National Laboratory (BNL) is coupled to a concomitant model-development and code-validation activity. In addition, measurements are being made at Battelle Columbus Laboratory (BCL) to augment the thermochemical data base needed in the VANESA code to permit refined radiological source-term predictions. The current scope and status of this research is reviewed. 相似文献
87.
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89.
V. V. Plikhunov S. Ya. Betsofen A. M. Mamonov V. S. Spektor 《Russian Metallurgy (Metally)》2007,(5):428-432
Microstructure, texture, and microhardness and residual-stress distributions are studied in a VT20 alloy welded shell consisting of two coaxial nested components connected by a circular weld. 相似文献
90.
We study a mechanism for maintaining the strength of cement-bonded iron-oxide-bearing briquets when heated under reducing conditions. These briquets retain their strength when heated in a reducing atmosphere: up to 700–750°C, strength retention is due to the cement stone; strength retention under further heating is due to the continuous metal shell formed on the surface of the briquet as the iron oxide in the surface layer of the briquet is reduced to iron. Fabrication and usage of briquets of iron-ore concentrate can be recommended as a wash material for blast furnaces. Disperse materials containing SiO2 and MgO should be added to the charge during fabrication of the briquets in order to improve the washing properties of briquet slag. 相似文献