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排序方式: 共有1169条查询结果,搜索用时 46 毫秒
1.
Shchelkunov E. B. Vinogradov S. V. Shchelkunova M. E. Pronin A. I. Buravitsyn D. A. 《Russian Engineering Research》2020,40(5):367-371
Russian Engineering Research - The theoretically possible reconfigurable parallel mechanisms are classified, in terms of the layout of guides on the base. Formulas are derived for the... 相似文献
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Although self-help/mutual-help groups, like Alcoholics Anonymous, are important factors in the recovery of many chemically dependent individuals, the large dropout rates from such groups and the awareness that many who drop out do not return to dependent behavior raises interesting questions about other paths to sustained abstinence and recovery. Current emphasis on treatment outcome studies provides a means for researching factors in both those who recover with and without the assistance of self-help/mutual-help groups. The authors suggest some questions which might be investigated. 相似文献
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V.N. Skokov V.P. Koverda A.V. Reshetnikov V.P. Skripov N.A. Mazheiko A.V. Vinogradov 《International Journal of Heat and Mass Transfer》2003,46(10):1879-1883
Thermal fluctuations under the transition from nucleate to film boiling of water on a wire heater and fluctuations of jet form during an outflow of superheated liquid from a pressure vessel were experimentally investigated. It has been found that power spectrum of the fluctuations has got a low frequency component corresponding to a 1/f law (flicker noise).The effect given is connected with the occurrence of nonequilibrium phase transitions in the systems: a crisis of heat transfer under the transition from nucleate to film boiling and a crisis of a flow in boiling-up of superheated liquid jet. 相似文献
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Yu. I. Vinogradov V. S. Aryutkin V. A. Kuryakin V. V. Travkin A. A. Yukhimchuk S. V. Fil'chagin 《Instruments and Experimental Techniques》2004,47(3):300-311
A computerized system for monitoring and controlling the gas-mixture preparation complex of the TRITON installation is described. The installation is designed for experimental investigations of muon-catalyzed fusion in triple mixtures of hydrogen isotopes H/D/T over wide ranges of temperature and pressure. The system is used to control the entire complex of gas-mixture preparation, the target parameters, and the gas-mixture composition, as well as to carry out radiation monitoring. Good performance characteristics, the high reliability of the system, and the possibility of its rapid adaptation to new tasks have been demonstrated in physics experiments. 相似文献
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A population balance method in which continuum and discrete phases are integrated is developed to simulate the evolution of polydisperse population of bubbles in a turbulent pipeline flow. The investigation is focused on the effect of the coalescence efficiency on this evolution. A dilute system of bubbles under microgravity conditions is considered. It is found that if the initial coalescence efficiency is low, a slight increase produces a significant effect on the bubble coalescence rate, and thus on the evolution of the population. If, however, the initial coalescence efficiency is high, its increase results in a marginal effect on the way the population evolves. The results of simulations are validated against experimental data on the population mean. 相似文献
8.
GI Kempen MJ van Heuvelen RH van den Brink AC Kooijman M Klein PJ Houx J Ormel 《Canadian Metallurgical Quarterly》1996,25(6):458-464
Molecular electrostatic potential (MEP) maps of certain 3-methoxy flavone derivatives having different anti-picornavirus activities have been studied. Geometries of the molecules were optimised and charge distributions computed using the AM1 molecular orbital method. Hybridization displacement charges (HDC) were combined with the L?wdin charge distributions to compute the MEP maps. Reliability of the method of computing MEP maps was tested by studying certain other molecules for which ab initio MEP results are available. The anti-picornavirus activities of the flavones have been shown to be related with negative MEP values in two regions, one near the 3-methoxy group and another in a diagonally opposite region near the substituent attached to the C7 atom of the molecules. 相似文献
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Acute graft rejection and delayed function are considered to be the major risk factors of short-term as well as long-term graft survival. We studied the impact of these factors on graft outcome among 109 renal transplant recipients. All recipients were treated with triple drug protocol. The recipients were divided into two groups: I group included 57 patients with delayed graft function (DGF), II group included 52 patients with immediate graft function (IGF). We studied graft survival, incidence of acute rejection, serum creatinine levels and the cause of graft loss for patients in both groups. Acute rejection episodes occurred in 49% of patients from DGF group and 45% of patients from IGF group. Graft survival in IGF group was better than in DGF group. Actuarial graft survival at 1, 2, 3 and 4 years in examined groups was 84%, 82%, 72%, 65% vs. 92%, 86%, 84%, 84%, respectively. One-year graft survival in patients with acute rejection from DGF group and IGF group was significantly lower than in patients who remained rejection free (69%, 74% vs. 94%, 96%). We concluded that delayed graft function decreases long-term graft survival, while immediate graft function has an excellent impact on graft outcome. Acute graft rejection is the strongest risk factor of graft loss. 相似文献