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81.
以分析新型防雷装置消雷器静态电场为例 ,提出一种非常适合于多个 CPU并行计算机上实现的并行算法——奇偶并行法。通过算例证实该算法容易实现、效率比较高 ,同时也容易推广至其它数值计算领域。最后给出伞形导体消雷器的静态电场分布 ,并首次提出了判别消雷器设计期间的优劣标准 ,为进一步设计消雷器奠定理论基础。  相似文献   
82.
Presents the citations, biographies, and selected papers of the 2004 recipients of the APA Award for Distinguished Professional Contributions to Applied Research (Robert J. Gatchel), the APA Award for Distinguished Professional Contributions to Independent or Institutional Practice in the Private Sector (Miki Paul), the APA Award for Distinguished Professional Contributions to Practice in the Public Sector (Rodney R. Baker), and the APA/APAGS Award for Distinguished Graduate Student in Professional Psychology (Tonia L. Nicholls). The Award for Distinguished Professional Contributions to Applied Research is given to a psychologist whose research has led to important discoveries or developments in the field of applied psychology. The Award for Distinguished Professional Contributions to Independent or Institutional Practice in the Private Sector recognizes outstanding service delivery by a licensed psychologist who is primarily engaged in the practice of psychology in a private sector setting. The Award for Distinguished Professional Contributions to Practice in the Public Sector recognizes outstanding service delivery by a psychologist who is primarily engaged in the practice of psychology in a public sector setting. The APA/APAGS Award for Distinguished Graduate Student in Professional Psychology is awarded on an annual basis by the Board of Professional Affairs (BPA) and the American Psychological Association of Graduate Students (APAGS) to a graduate student who has demonstrated outstanding practice and application of psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
In recent years, heavy liquid metals have found exercise as possible coolants and targets in the conversion of radioactive elements in accelerator driven systems (ADS). Liquid lead-bismuth eutectic alloy is one of candidates for this using tanks to its suitable nuclear and physical properties. Performed examination was aimed at research of compatibility choice materials for parts of ADS with liquid Pb-Bi eutectic alloy, influence of composition choice materials on their corrosion resistance, influence of temperature and oxygen content. We performed corrosion tests of 1000 h each on approximately 20 types of structural steels (austenitic, ferritic and martensitic) in convection loops with flowing Pb-Bi at 500 and 400 °C and using different oxygen concentrations. The impact of Fe, Cr, Ni, Mn, Si, Al and Mo content on the corrosion stability of these steels was measured without and after preliminary passivation through creating thin spinel or oxide layers on their surface.  相似文献   
84.
Sensors are the major part of an active oxygen control system (OCS) to be used in ADS reactors employing lead bismuth eutectic (LBE). We tested Pt/air and Bi/Bi2O3 probes based on yttria-stabilized zirconia (YSZ) solid electrolytes. The sensors were calibrated by evaluating the electromotive force (EMF) - temperature dependencies in oxygen un-/saturated stagnant LBE compared to the van’t-Hoff’s isotherm. Also, probe kinetics while changing the H2/H2O ratio was studied. Typical, reproducible curves are presented confirming attainment of oxygen equilibrium between the fluids. The sensor outputs are deterministic, predictable. Exceptional small drifts were due to interfacial kinetics, not to the sensors behavior. Simultaneous testing of several probes in one melt was performed. The sensors seemed to be qualified for large scale use.  相似文献   
85.
Liquid-solid reaction under irradiation (LiSoR) experiments are aimed at understanding the effects of liquid lead-bismuth eutectic (LBE) corrosion and embrittlement under irradiation on structural materials, which is one of the key items of the materials R&D for the future accelerator-driven system (ADS). The LiSoR setup is basically a LBE loop with a test section irradiated with 72 MeV protons. The second irradiation was conducted for about 34 h and terminated after a leakage of LBE was detected. Post-irradiation examinations (PIE) are being performed on both the tube and tensile specimen in the test section. Optical microscopy, scanning electron microscopy, transmission electron microscopy and microhardness tests have been completed. The results show that a crack formed in the irradiation zone of the tube. In the material in the irradiation zones of both the tube and the tensile specimen dislocation cell structure is well developed, which indicates heavy deformation due to thermal fatigue. The crack should start at the inner surface and propagate to the outer surface. The fracture surfaces of the crack are dominated by a brittle cleavage fracture mode. However, on the surfaces of the tensile specimen, no microcracks are observed.  相似文献   
86.
刘靖  温志强 《山东冶金》2008,30(1):52-53
为提高卷取温度的控制精度,同时为准确模拟B510L钢轧后冷却的温度场和分析工艺参数对品种钢组织性能的影响,采用激光脉冲法测得了B510L钢的热扩散率α;采用示差扫描量热计法测得了定压比热容Cp,最终求得了不同温度下的导热系数λ.实验结果表明:B510L钢的导热系数随温度的升高总体呈下降的趋势,但在相变区内有所波动.  相似文献   
87.
As one of the largest gene families, F-box domain proteins have important roles in regulating various developmental processes and stress responses. In this study, we have investigated a rice F-box domain gene, MAIF1. The MAIF1protein is mainly localized in the plasma membrane and nucleus. MAIF1 expression is induced rapidly and strongly by abscisic acid (ABA) and abiotic stresses. MAIM expression is also induced in root tips by sucrose, independent of its hydrolytic hexose products, glucose and fructose, and the plant hormones auxin and cytokinin. Overexpression of MAIF1 reduces rice ABA sensitivity and abiotic stress tolerance and promotes rice root growth. These results suggest that MAIF1 is involved in multiple signaling pathways in regulating root growth. Growth restraint in plants is an acclimatization strategy against abiotic stress. Our results also suggest that MAIF1 plays the negative role in response to abiotic stress possibly by regulating root growth.  相似文献   
88.
余热排出系统管道发现的热疲劳裂纹问题关系到压水堆的安全。本文基于开源有限元软件Code_Aster,采用Lagoda-Macha-Sakane模型预测了余热排出系统管道材料304L不锈钢的疲劳寿命,并根据预测结果提出了改进的Lagoda-Macha-Sakane模型。采用改进的Lagoda-Macha-Sakane模型对余热排出系统管道的热疲劳寿命进行了预测,结果表明预测热疲劳寿命与试验热疲劳寿命吻合。  相似文献   
89.
介绍基于89C51单片机和DHT22数字温湿度传感器利用nRF24L01无线射频芯片构成的无线温湿度采集系统。系统采用无线分布式结构,提高了节点的可移动性、节约系统实现成本,而且易于安装和维护;同时实现了对多个温湿度测量点的循环采集和显示,并利用串行通信将采集到的数据传送到上位机进行分析处理。经检验,系统具有良好的可靠性及较高的精度。  相似文献   
90.
某装置中的316L不锈钢制加热器在运转不久即在管口局部区域发生严重腐蚀.经对加热器进行宏观检验和理化分析,认为该腐蚀是由于加热器在制造中引起了局部材料敏化而使耐蚀性能下降所致.提出了改进建议.  相似文献   
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