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991.
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994.
The solubilities of chloride (Cl) in liquid magnesium (Mg) have been determined from the analysis of quenched samples of liquid Mg equilibrated with NaCl-MgCl2 melts of different compositions at temperatures in the range 650–790 °C. As an example, the solubility of Cl in liquid Mg in contact with pure MgCl2 at 735 °C was found to be approximately 18 ppm. The Cl solubility was found to be proportional to the square root of the MgCl2 activity in the NaCl-MgCl2 melt, indicating that MgCl2 dissolved according to the reaction 0.5MgCl2 + 0.5Mg(l) = MgCl (in Mg). The temperature dependency of the solubility also was measured. Thermodynamic values related to the dissolution of MgCl2 in liquid Mg have been estimated.  相似文献   
995.
Bingo Voting     
Wahlen bringen den Willen des Volkes zum Ausdruck und stellen damit einen fundamentalen Baustein für jede Demokratie dar. Forderungen nach einer schnelleren Ausz?hlung haben dazu geführt, dass vermehrt Wahlmaschinen Einsatz finden, trotz der massiven Kritik, die von verschiedenen Seiten ge?u?ert wird. Der Beitrag stellt ein kryptographisches Verfahren vor, das Wahlen mit Wahlmaschinen erlaubt, ohne dabei an Transparenz und Nachvollziehbarkeit einzuben. Das Verfahren wurde mit dem Deutschen IT-Sicherheitspreis 2008 ausgezeichnet.  相似文献   
996.
Finite element formulation for inflatable beams   总被引:2,自引:0,他引:2  
The discretized nonlinear equations for bending and buckling of inflatable beams are written by use of the virtual work principle with Timoshenko's kinematics, finite rotations and small strains. The linearized equations around a pre-stressed reference configuration are then deduced, giving rise to a new inflatable beam finite element. The stiffness matrix contains the shear coefficient and the internal pressure. Use is made of the particular 3-node beam element to investigate the bending and the buckling of a cantilever beam, the deflection of a pinched torus and the buckling of a torus submitted to a radial compressive force. The numerical results obtained with the beam element are shown to be close to analytical and three-dimensional (3D) membrane finite element results. The validity of the numerical results is discussed, in connection with the concepts of the crushing force or the wrinkling pressure of the inflated beam.  相似文献   
997.
Three social–cognitive models are presented as alternatives to dissociation theories of hypnotic involuntariness. In Model I, people are seen as intentionally enacting responses without being aware of the volitional quality of their acts. In Model II, hypnotic behaviors are seen as prepared responses that are triggered directly by suggestion. The first model corresponds to E. R. Hilgard's (1986) neodissociation theory and the second to K. S. Bowers's (1992) theory of dissociated control, but without positing dissociative mechanisms as explanatory constructs. These constructs are replaced by a consideration of the automaticity that is inherent in commonplace intentional behavior and the degree to which subjective experience is affected by beliefs and expectations. Finally, a composite model reconciling the contradictions between the two prior social–cognitive models is presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
设计者用CFL(紧凑式荧光灯)中的镇流器IC(如国际整流器公司的IR53HD420)来加热灯丝、点亮灯泡.为电灯提供电流(参考文献1).制造商大量生产这些IC,它们的价格大约为2美元.  相似文献   
999.
减少二氧化碳的排放和可持续性发展——这些是我们这个时代的流行语。为了不辜负这些今天和明天的流行语,需要先进的电控驱动技术涉足新的领域。其中一个最大且最具挑战性的领域是汽车产业.现有的功率模块无法满足该行业的严格要求,这就是为什么它们不能服务市场的原因。为了面对这项挑战,赛米控开发了SKiM(赛米控集成模块),适用于汽车工业的IGBT模块。[编者按]  相似文献   
1000.
Monophosphoryl lipid A (MLA), a derivative of the minimal substructure of lipopolysaccharide (lipid A) possesses immunomodulatory activity of the parent lipid A yet enjoys reduced toxicity. It has previously been reported that pretreatment with MLA reduces myocardial infarct size and stunning in dogs following ischemia and reperfusion. The aim of this study was to evaluate the ability of monophosphoryl lipid A (MLA) to preserve global cardiac function and peripheral hemodynamics in a rabbit model of prolonged regional ischemia (90 min), and reperfusion (6 h). An evaluation of potential mechanisms by which MLA may preserve cardiac function was also undertaken. Single dose pretreatment with MLA (35 micrograms/kg i.v.) 24 h prior to ischemia resulted in significant improvement in left ventricular developed pressure, dP/dt, rate-pressure product and mean arterial pressure during reperfusion (P < 0.05 v control). Although in this model of prolonged ischemia MLA pretreatment did not reduce infarct size (54.5 +/- 11.4% in control v 63.3 +/- 8.3% in MLA, P = N.S.), evaluation of myocardial adenylate and adenosine catabolite pools at the end of ischemia indicated a preservation of ATP and ADP and a decreased production of downstream adenosine catabolites including inosine, xanthine and uric acid. Adenosine kinase, but not 5'-nucleotidase (5'-NTase) or adenosine deaminase activity determined following reperfusion was 76% and 60% higher (P < 0.05) in non-risk and post-ischemic myocardium of MLA pretreated rabbits compared with controls. Although there was a trend toward lower tissue myeloperoxidase activity in post-ischemic myocardium from treated rabbits, the results were not significantly different from control animals. These results suggest that a 24-h pretreatment with MLA, without further treatment during ischemia or reperfusion was associated with: (1) preservation of global myocardial function during reperfusion; (2) preservation of myocardial high energy adenylates and reduced formation of adenosine catabolites during ischemia; (3) elevated myocardial adenosine kinase activity. Increased recycling of adenosine to phosphorylated nucleotides may result from MLA's affect on adenosine kinase, which could explain the drugs effect on adenylate and adenosine metabolite pools.  相似文献   
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