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排序方式: 共有882条查询结果,搜索用时 15 毫秒
171.
Alexander Döß Markus Schubert Michael Wiezorek Uwe Hampel Felix Flegiel Christoph Windmeier Eckhard Schleicher Christoph Schunk 《化学,工程师,技术》2021,93(7):1126-1133
Tailored conditioning and control of flashing feeds in industrial applications requires knowledge of the evolving flow morphology and phase fractions along the feed pipe. Design methods obtained from reference systems (e.g. water-air) are hardly applicable for commercial scales and critical fluid properties (e.g. high vapor densities, low surface tension). In this study, the flow morphology of flashing feeds in a novel refrigerant test rig at critical fluid properties was analyzed using wire-mesh sensors at two locations along the feed pipe and experimental data from the water-air system. 相似文献
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The latencies of 71 gonadectomized male and female ferrets to approach and interact with a sexually active stimulus male were measured after subcutaneous (sc) administration of estradiol benzoate ([EB] 0, 5, 10, or 15 μg/kg) in adulthood. Receptive responsiveness to stud males was also assessed during additional tests. Control females gonadectomized on Postnatal Day 35 displayed a dose-dependent reduction in approach latencies to the stud male that did not occur in control males castrated on Day 35. The approach latencies of males castrated on Day 20 or Day 5 were intermediate between these 2 extremes. Equivalent dose-dependent reductions in approach latencies were observed in Ss ovariectomized on Day 5 and implanted sc with silastic capsules containing either no hormone or different doses of testosterone over Days 5–20 or 20–35. Equivalent dose-dependent increments in acceptance quotients were obtained in all groups following EB treatment. Results suggest that the capacity to display the proceptive, or appetitive, components of feminine sexual behavior is normally reduced in male ferrets as a consequence of the perinatal action of testicular hormones, whereas receptive behavioral capacity is retained in males of this species. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Introduction to the special issue on high-power electromagnetics (HPEM) and intentional electromagnetic interference (IEMI) 总被引:3,自引:0,他引:3
Radasky W.A. Baum C.E. Wik M.W. 《Electromagnetic Compatibility, IEEE Transactions on》2004,46(3):314-321
A new threat to civil society has recently emerged. It is known as intentional electromagnetic interference (IEMI) and covers the threat of intense electromagnetic disturbances that may be applied to the sophisticated electronic systems that are so important to our daily lives. This paper provides a brief background for the threat, defines important terms, describes the different types of electromagnetic threats, explores the importance of topological concepts, summarizes the current understanding of equipment susceptibility, provides an overview of protection concepts, and summarizes the ongoing work in international standardization. This paper also serves as the introduction to the IEMI papers in this special issue. 相似文献
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The chemical vapor deposition of copper and copper alloys 总被引:1,自引:0,他引:1
The chemical vapor deposition of copper and copper alloys for very large scale integrated interconnects is described using a series of Lewis base stabilized copper (I) 1,1,1,5,5,5-hexafluoro-2,4-pentanedionato (hfac) complexes. When the Lewis base is dimethyl-1,5-cyclooctadiene, high-purity copper metal is deposited at substrate temperatures from 150 to 250 °C. The deposition rate becomes mass-transport limited at the higher substrate temperatures, but excellent filling of sub-micron vias (3:1 aspect ratio) was achieved. The deposition of copper-tin alloys can also be achieved when vinyl trialkyltin is used as the Lewis base. At 180 °C, a carbon-free copper film, containing 0.6 at.%Sn, is deposited. A very strong substrate temperature dependence towards film purity was observed and results from thermal decomposition of the tin-containing ligand. These preliminary results demonstrate the utility of using single-source, mixed-metal precursors for copper alloy formation. 相似文献
179.
Graph models for investigating behavior of mobile users in an environment with several access areas, such as cells in cellular networks, Bluetooth clusters in devices controlling ad hoc networks, or similar configurations, are presented in the paper. Based on these models, distributions of a number of communication links in different access areas are derived. 相似文献
180.
T Baldewicz K Goodkin DJ Feaster NT Blaney M Kumar A Kumar G Shor-Posner M Baum 《Canadian Metallurgical Quarterly》1998,60(3):297-308
OBJECTIVE: Previous research has demonstrated that a theoretical model including measures of life stressors, social support, and coping style significantly predicts psychological distress. This study tested plasma pyridoxine (vitamin B6) deficiency status as a predictor of overall psychological distress and specific mood states in this model, controlling for HIV-1 serostatus. METHOD: Subjects included HIV-1+ (N = 76) and HIV-1- (N = 58) recently bereaved homosexual men. At baseline, subjects completed a battery of psychosocial questionnaires, together with a physical examination and venipuncture. The Profile of Mood States (POMS) provided measures of overall psychological distress as well as specific mood states. Pyridoxine deficiency status (a categorical measure of deficient vs. adequate status) was determined with a bioassay of erythrocyte aspartate aminotransferase activity. RESULTS: Pyridoxine deficiency was a significant predictor of increased overall psychological distress in this model, controlling for life stressors, social support, coping style, and HIV-1 serostatus. In post hoc analyses of specific mood state effects, pyridoxine deficiency status was significantly associated with increases in depressed, fatigued, and confused mood levels, but not with those of anxiety, anger, or vigor. DISCUSSION: These findings suggest that adequate pyridoxine status may be necessary to avert psychological distress in the setting of bereavement. Inasmuch as pyridoxine is a cofactor for 5-hydroxytryptophan decarboxylase--an enzyme in the biosynthesis pathway of serotonin--serotonin level in the brain is implicated as the mediating factor. 相似文献