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161.
162.
The catalysts of CeO2 and the mixture of CeO2 and CuO were prepared, and the activities of these catalysts for completely oxidizing benzene were studied.The results show that the optimal proportion of CeO2/CuO is 6: 4.The highest temperature at which benzene was completely oxidized on these catalysts at different airspeed was measured.Compared these catalysts with the noble metal used, our catalysts had superiority in the resources and the industrial cost besides good activities. 相似文献
163.
Yu. G. Volodin 《Thermal Engineering》2007,54(5):399-402
The results of experimental study of unsteady effects on local heat transfer coefficients caused by abruptly increasing of the gas flow temperature in the inlet section of a cylindrical channel are presented. 相似文献
164.
Heidi Bernas Arie J. Plomp Johannes H. Bitter Dmitry Yu. Murzin 《Catalysis Letters》2008,120(1-2):8-13
The density functional theory (DFT/B3LYP) calculations were applied to investigate the interaction of a Pt6 particle with the ZSM-5 zeolite framework. The electronic structure of the metal particle is strongly affected by the interaction with basic framework oxygens and acid sites of the zeolite support. Adsorption on basic sites (Eads = 6 kcal/mol) favors the formation of the electron enriched metal cluster. Interaction of the platinum cluster with the acid site characterized by stabilization energy of 47 kcal/mol results in oxidation of the metal particle and suppression of Brønsted acidity of the support. The hypothesis is put forward that the oxidized platinum particle can function as an active site for the alkane isomerisation on platinum supported high silica zeolites. 相似文献
165.
The effects of a biquadratic exchange and an external magnetic field on the phase states of a twodimensional non-Heisenberg ferromagnet have been studied with allowance for magnetoelastic and magnetodipolar interactions. 相似文献
166.
Yu. P. Nikolaev 《Automation and Remote Control》2004,65(12):1904-1914
The D-decomposition of a two-dimensional plane of arbitrary coefficients of a discrete characteristic polynomial is studied. The geometry of the boundary curve is analyzed and its common properties with a linear discrete system of any order are described. Example are given. 相似文献
167.
S. M. Obraztsov G. A. Birzhevoi Yu. V. Konobeev V. A. Solov'ev O. S. Silkina 《Atomic Energy》2004,96(2):111-116
The results of a computational experiment with a neural-net model simulating the effect of the chemical composition on the plastic properties of ÉP-450 steel are presented. It is shown that computer-aided development of reactor steel with prescribed properties is, in principle, possible. 相似文献
168.
A. V. Zrodnikov G. I. Toshinskii O. G. Grigor'ev Yu. G. Dragunov V. S. Stepanov N. N. Klimov I. I. Kopytov V. N. Krushel'nitskii A. A. Grudakov 《Atomic Energy》2004,97(2):528-533
The results of development work on the SVBR-75/100 modular fast reactor cooled by lead–bismuth coolant are presented. The design is based on the experience gained operating reactors in nuclear-powered submarines. The SVBR-75/100 reactor is inherently safe because of its low power, the chemical inertness and high boiling point of the lead–bismuth coolant, and the integrated basin-type arrangement of the first-loop equipment. This eliminates the conflict between the safety and economic requirements that is characteristic of conventional-type reactors. The lower power makes it possible to build the reactor in a factory and deliver the reactor using any form of transportation to the nuclear power plant site. All safety systems operate passively. Most of these systems are used as normal-operating systems. This creates conditions for multipurpose applications of such reactor modules in developed and developing countries. 相似文献
169.
Age assessment and control of the reliability of the coolant flow-rate measurement system of the RBMK-1500 reactor at the Ignalina nuclear power plant are examined. A statistical analysis is made of the data obtained from measurements of the techanical characteristics of SHADR-32M flow meters. A mathematical model of the aging of flow meters and reliability estimates is constructed. A strategy is developed for replacing SHADR; this strategy makes it possible to support the required relaibility of the entire coolant flow-rate measurement system. 相似文献
170.