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排序方式: 共有7956条查询结果,搜索用时 15 毫秒
931.
932.
933.
Some results on synchronization and maximality of very pure codes are given. 相似文献
934.
935.
Two methods for solving nonconservative problems by applying the quadratic functional are presented. The corresponding approximate methods of solution are obtained by using suitable polinomial trial functions and are illustrated by solving Beck's and Leipholz's rods. 相似文献
936.
This study examines the relationship between trainees' conjugal family experience, current intergenerational family relationships, and the client's perception of the therapeutic alliance. Participants were 74 first practicum family therapy trainees, representing two family therapy programs, and 90 clients. Results indicated a moderately significant relationship between conjugal family experience and trainees' reported intergenerational intimacy with parents. Additionally, clients whose therapists had conjugal family experience reported a slightly more favorable therapeutic alliance than clients whose therapists did not have conjugal family experience. Additionally, trainees with conjugal family experience reported more current intimacy and individuation than nonconjugal trainees and felt less intimidated by their parents. 相似文献
937.
Cepeda-Benito Antonio; Reynoso José; McDaniel Eric H. 《Canadian Metallurgical Quarterly》1998,6(3):248
Previous assessments of associative nicotine tolerance may have confounded associative effects with novelty-induced stress effects, instrumental learning effects, or both. That is, subjects were tested in novel environments, allowed to practice the test response, or both during the tolerance development phase. In the first study, 32 male Sprague-Dawley rats were injected with various doses of nicotine and tested for nociception in the tail-flick and hot-plate tests to assess nicotine's analgesic effects. In the second study, 35 rats received nicotine explicitly paired or unpaired with a distinctive test context. All animals were equally preexposed to the test environment, and none had the opportunity to practice the test response. Paired rats developed greater nicotine tolerance than unpaired rats. This context-dependent (associative) tolerance effect was found with both tail-flick and hot-plate tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
938.
Antonio M. Martin Valerie I. Bailey 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1984,34(1):70-74
Peat and its derived products such as peat extracts or hydrolysates offer a variety of possibilities as raw materials for the development of chemical and biochemical processes. Acid hydrolysis of peat yields soluble carbohydrates which can be utilised as fermentation media. In this work, Sphagnum peat moss was hydrolysed under various conditions of H2SO4 concentration, retention time, temperature, peat concentration, peat particle size distribution and original moisture content in the peat. The results suggest that mild conditions of hydrolysis, which will minimise possible negative effects on other nutrients available in peat, are adequate for the release of the carbohydrates present in peat. It was found that peat particle size distribution and original moisture content as well as peat concentration will also affect the yield of carbohydrates obtained. 相似文献
939.
This paper discusses the process of the generation of hot points in reverse biased p?n diodes. In this work we use a simple lumped thermal model of the diode. The stability of the nearly uniform distribution of the current through the junction of the diode is analysed. This analysis determines, for every diode, the maximum value of the current under which the junction will be free of current constriction, or hot points. It is concluded that, for diodes which are small enough, a hot point cannot appear. Nevertheless, if a nearly ideal voltage generator is used to drive the diode, a thermal instability of the whole junction can appear. 相似文献
940.
Antonio A. Caminos Rafiqul Gani Esteban A. Brignole 《Computers & Chemical Engineering》1984,8(2):127-136
A steady state liquid-liquid extractor model using the UNIFAC group contribution method for phase equilibria has been developed. A heuristic method, which limits the number of stage calculations per iteration to a low number is used, according to the residuals calculated in the previous iteration, the method either selects or rejects a stage for the calculations. With this approach, the same accuracy in results have been obtained at about half the computing time with respect to without use of heuristic method. The model has been applied to simulate staged extractors as well as continuous extractors (plate columns). The model is based on a very robust flash calculation routine and on a versatile package (UNIFAC) for the prediction of thermodynamic properties. 相似文献