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81.
Developed 2 measures based on G. A. Kelly's Rep Grid Test, one dealing with personal events and the other with general societal events. Results from 258 undergraduates show that internals used significantly more internal constructs than did externals and that Ss chose more internal constructs on the personal than on the societal measure. Results suggest that the internal-external dichotomy is reflected in and may be mediated by modes of thinking and categorization. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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In order to assess the suitability of stable initiators for the high pressure polymerization of ethylene, polymerization tests were carried out in a stirred autoclave in continuous operation. The pressure used was 1700 bar, the average residence time 30 seconds and the temperature was adjusted to between 200 and 360°C. The initiator concentration in the ethylene feed varied between 4 and 40 mol ppm. Di-tert-butyl peroxide, di-tert-amyl peroxide, tert-butyl hydroperoxide, and 3,4-di-methyl-3,4-di-phenyl hexane, a C? C labile compound, were chosen for use as stable initiators. The level of conversion and the specific initiator consumption were determined. The polymers obtained were characterized by measuring their density, average molecular weight, and melt flow index. The stable initiators used were all characterized by a very low level of consumption. In the case of dialkyl peroxides and alkyl hydroperoxide, the optimum application temperature is substantially above 200°C and above 300°C in the case of the C? C labile initiator. Under these conditions, polymers with a low density, a low molecular weight, a narrow molecular weight distribution and a high melt flow index were obtained. 相似文献
85.
Daily blood samples were obtained from 5 postmenopausal patients for 21 days and analyzed for plasma follicle stimulating hormone (FSH), luteinizing hormone (LH), estrone, estradiol, progesterone, and serum T4. On days 8 through 14, oral thyrotropin-releasing hormone (TRH) was administered, 50 mg, 4 times a day. All patients showed asignificant T4 response. There was, however, no significant change in the plasma FSH, LH, estrone, estradiol, or progesterone. We conclude that oral administration ofTRH has no influence on the elevated circulating concentration of FSH and LH seen in the postmenopausal female. 相似文献
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Prof. Frederic G. Hammitt Ph. D. Prof. t. sc. Stefan Krzeczkowski Prof. Dr. habil. t. sc. Jerzy Krzyżanowski 《Forschung im Ingenieurwesen》1981,47(1):1-14
The state of art and ongoing research concerning the flow of wet steam in large steam turbines is reviewed, particularly from
the viewpoint of the behavior of the liquid film deposited upon the stationary blading. New experimental results concerning
the non-steady behavior of the film and the resultant wavelet formation patterns under the action of high-velocity low-pressure
steam flow are presented. These results are then correlated as a flow regime “map” showing various flow regions in terms of
steam velocity (or relative steam-film velocity since film velocity is relatively very small) vs. film flow rate per unit
transverse distance.
The distribution of liquid droplets shed from the blade trailing edge in the wake are studied as a function of distance downstream,
steam velocity, and liquid film flow rate. In addition the droplet size is correlated in terms of critical droplet Weber number
and compared with results of previous investigators. High-speed photographs of droplet distortions in a high-velocity air
stream are also included. 相似文献
88.
Using files of the Animal Neoplasm Registry (ANR) in Alameda and Contra Costa Counties, California, we conducted a retrospective study to compare the degree of inbreeding in the ancestry of purebred dogs with mammary and other cancers, and of those without tumors. Wright's coefficients of inbreeding, calculated for all animals in the three groups, ranged from 0.000 to 0.535. The median inbreeding coefficients of the mammary cancer and comparison groups (consisting of other cancers) were approximately twice that of the nonneoplastic group, but neither difference was statistically significant. Dogs with mammary adenocarcinoma and mixed mammary cancer had similar degrees of inbreeding. 相似文献
89.
Fiber-coupling efficiency for free-space optical communication through atmospheric turbulence 总被引:3,自引:0,他引:3
High-speed free-space optical communication systems have recently used fiber-optic components. The received laser beam in such a system must be coupled into a single-mode fiber at the input of the receiver module. However, propagation through atmospheric turbulence degrades the spatial coherence of a laser beam and limits the fiber-coupling efficiency. We numerically evaluate the fiber-coupling efficiency for laser light distorted by atmospheric turbulence. We also investigate the use of a coherent fiber array as a receiver structure and find that a coherent fiber array that consists of seven subapertures would significantly increase the fiber-coupling efficiency. 相似文献
90.
Reviews and evaluates school consultation research conducted during the past decade. Attention is given to the breadth and quality of the present consultation knowledge base, the appropriateness of data analysis procedures, and the impact of consultation research findings on consultation training. Recommendations for future directions in school consultation research are offered from both methodological and substantive perspectives. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献