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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
B. K. Dutta 《Acta Mechanica》1989,78(3-4):255-262
Summary The conjugate problem of heat transfer from an accelerating surface in presence of suction and blowing has been solved analytically. The effects of different parameters on cooling of the surface have been discussed.With 3 Figures 相似文献
993.
994.
It has been found that solutions of myosin (10 mg/ml) form gels at 5°C if the pH is decreased slowly, by dialysis, to a value in the region of 2.5 to 5.5. Gel strength displays strong dependence on final pH, having a maximum at about pH 4.5. Salt (KCl) concentration was found to affect gel strength positively and linearly. Differential scanning calorimetry revealed that the myosin of pH-induced gels absorbed no thermal energy when heated, implicating acid-induced denaturation as the basis of gel formation. By comparison with heat-induced gelation of myosin and from the fact that low pH is conducive to filament formation, it is suggested that filaments may also be involved in the gelation process. 相似文献
995.
A. A. Nikitin O. V. Zausova N. V. Titova A. B. Shapovalov E. B. Vlasova L. A. Popova 《Glass and Ceramics》2007,64(9-10):373-374
The possibility of using the granulated form of biocompatible material made of calcium-phosphate glass ceramic BGC for treatment of maxillary cysts was demonstrated. 相似文献
996.
997.
With the rapid expansion of markets for telecommunications services and equipment, both national and international, one sees an increasing frequency of alliances in which each of two firms seeks to use the other to complete its portfolio strengths. Often this combination enables firms to achieve the product differentiation that seems to be the key to competitive advantage in modern telecommunications markets. This alliance may take the form of a « joint venture », which in the paper includes as limiting cases a subsidiary wholly owned by one firm, a technology licensing arrangement, and direct exporting. The model of such a venture presented here, although simple, is rich enough to illustrate the influence of four types of factors on the negotiations that set up the venture: demand, costs, risk, and regulatory constraints. We characterize the sets of acceptable and efficient arrangements, under various assumptions about exogeneous factors. The partners must choose among these by some form of bargaining. 相似文献
998.
A mathematical simulation model is presented describing the discharge process of metal hydrides. The model is applied to FeTi-single tube and multiple tube beds and the results are compared directly to the results of experimental investigations. Furthermore, the most important engine parameters, with respect to the operation with metal hydride stored hydrogen, were determined for the nonsteady FTP 72-driving cycle. Minimum hydride quantities, necessary to supply the engine with hydrogen during the warm-up phase, were calculated for different starting temperatures and initial hydrogen contents of the bed. 相似文献
999.
B. I. Venzel' E. A. Egorov V. V. Zhizhenkov V. D. Kleiner 《Journal of Engineering Physics and Thermophysics》1985,48(3):346-350
The method of proton magnetic resonance is used to determine the melting point of ice particles in the pores of monodisperse porous glasses ranging from 10 to 1000 Å in radius.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 48, No. 3, pp. 461–466, March, 1985. 相似文献
1000.