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941.
The kinetics of the reaction of olefin synthesis from dimethyl ether and methanol is studied. A kinetic model of the nine-route reaction under study is constructed. The constants of the model are estimated using experimental data. The adequacy of the model to the results of experiments is shown 相似文献
942.
Y.M. Wong W.P. Kang J.L. Davidson J.H. Huang D.V. Kerns 《Diamond and Related Materials》2008,17(4-5):552-555
A novel integrated vacuum field emission (VFE) differential amplifier (diff-amp) utilizing carbon nanotube (CNT) emitters has been developed. A dual-mask microfabrication process was employed to achieve a VFE diff-amp by integrating identical CNT VFE transistors with built-in split gates and integrated anodes. The identical pair of triode amplifiers was well-matched in their device characteristics. The measured ac small-signal characteristics of the diff-amp showed a common-mode-rejection ratio (CMRR) of ~ 320 (~ 50 dB). The proposed analytical model of the CMRR was verified to be in good agreement with the experimental data. The successful implementation of the CNT diff-amp demonstrates a new way to achieve temperature and radiation tolerant VFE integrated microelectronics. 相似文献
943.
This paper presents data relating to the performance of sprinklers and detectors in real office fire situations. For sprinklers, these data are additional to that associated with the standardized testing used to determine the design delivery density and pressure requirements for various occupancy situations, and provide a useful insight into the effect of sprinklers on developing fires with various office situations. The data given in this paper include the times for activation of various types of sprinkler heads (normal and fast response), the efficacy of the systems as far as extinguishment is concerned, estimates of the maximum size of the fires prior to commencement of extinguishment and associated air temperatures at various locations within the office enclosures. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
944.
The results of the oxidation of carbon nanofibers and materials obtained on their basis are presented; these results demonstrate that the nanofibers were formed by carbon with different degrees of crystal structure ordering. The experimental data supported previous hypotheses that amorphous carbon results from the decomposition of metal carbides. The subsequent formation of spatial structures and the appearance of crystalline carbon species resulted from catalytic graphitization. It was demonstrated that sorbents can be prepared based on carbon nanofibers after pyrolytic consolidation followed by activation, and these sorbents are more effective than well-known sorbents. 相似文献
945.
Yu. V. Pokonova 《Solid Fuel Chemistry》2008,42(6):369-372
Impregnants prepared from shale phenols for cellular materials had a cohesive strength of 2.4–18.5 J/m2 and a specific elongation of 160–170%. The adhesive strength toward a metal was 3.5–6.0 J/m2; in the case of concrete, it was greater than the concrete strength. 相似文献
946.
I. I. Nemets Yu. N. Trepalina E. A. Doroganov 《Refractories and Industrial Ceramics》2008,49(3):205-208
Physicotechnical properties are provided for concretes based on mechanically-activated phosphate suspensions previously modified
with magnesium and aluminum hydroxides and silicic acid. The results obtained demonstrate the efficiency of using modifying
additions in order to increase the strength and heat resistance of corundum concretes.
Translated from Novye Ogneupory, No. 5, pp. 32–35, May 2008. 相似文献
947.
A. N. Karapetyan I. A. Gribova A. P. Krasnov Yu. N. Studnev A. K. Pogosyan K. V. Oganesyan 《Journal of Friction and Wear》2007,28(6):546-550
The results of investigation of the modification of the Armenian minerals with fluorine-containing oligomers show that a modified product appears when the mineral fillers are treated with fluoroalkanes. The product preserves the structure of the fillers with a “grafted” fluoroalkane layer in which chlorine atoms locate mainly over their periphery. The composite materials based on heterochained polymers and the modified fillers possess a stronger wear resistance and a low friction coefficient. 相似文献
948.
K. O. Boltar I. D. Burlakov A. M. Filachev E. A. Klimanov V. P. Ponomarenko V. N. Solyakov V. I. Stafeev 《Optical Memory & Neural Networks》2007,16(4):234-247
The recent researches and technological developments of middle and long wavelength infrared HgCdTe photovoltaic detectors
are presented. Structure, topology, design and performance of HgCdTe photodiodes, silicon readout electronics, Focal Plane
Arrays both staring and time delay and integration types, thermal imagers are discussed. Negative differential conductance,
bistability and high frequency oscillations under background infrared radiation in HgCdTe photodiodes are reported. 相似文献
949.
V. V. Evgrafov V. V. Pavlovsky V. E. Pavlovsky 《Journal of Computer and Systems Sciences International》2007,46(5):836-841
The problem of synthesizing trajectories, planning and implementing the motion of a mobile robot is investigated. The statement of the problem is motivated by the need for designing an optimal control of robots with two wheels controlled independently. Mobile robots with this kinematic scheme are called robots with “differential drive.” 相似文献
950.
I. V. Smirnov 《Automatic Documentation and Mathematical Linguistics》2007,41(3):108-113
The task of ascertaining minimal semantic-syntactic text units within the framework of the task of the semantic analysis of texts in the Russian language is considered. The use of the DSM-method for producing rules for ascertaining the meanings of syntaxemes is described, the setting of the goal of producing rules in DSM-method terminology is presented. The analysis of the results of computer experiments and the causes of the presence of contradictory rules are given. 相似文献