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11.
杜宇芳 《信息技术》2002,(3):23-23,27
介绍了微型计算机的两种不同类型的泄漏电流的危害及其测量方法。  相似文献   
12.
The paper is devoted to the effect of compressibility of the avalanche snow impacting an obstacle. Compression shocks generated by obstacle cause high pressure peaks at first instants of impact. That is why the account of compressibility is essential for the understanding of measurements and the design of structures. The main problem in calculation compression shocks in avalanches is to formulate an equation of state for moving snow in impact. Two different types of equations of state are proposed depending on the type of the avalanche (low-density and high-density flows). The approach is not totally new. It was earlier proposed mainly in Russian literature. Here a brief review of the previous work is given with discussion of some gaps in it. The theory is reformulated and further developed to account thermodynamical equations. The simplest case of a normal compression shock in an avalanche flow is studied. Examples of estimations of pressure and density behind a shock are given. It is important to emphasize that the Mach number plays an important role in the theory of compressible flows so it should be taken into account (together with the Froude number) in calculation and modelling an avalanche impact pressure.  相似文献   
13.
BACKGROUND: The application of lipase‐rich enzyme pools (such as the crude solid enzymatic preparation (SEP) obtained from Penicillium restrictum solid‐state fermentation of agro‐industrial wastes) to activated sludge systems may be an effective strategy for preventing various operational problems. The continuous addition of SEP to the treatment system can become cost‐prohibitive when in situ production and/or storage are factored in. The application of SEP to high‐fat wastewater treatment would only be justified as an emergency measure, such as a sudden increase in the fat content of the bioreactor influent. Therefore, the primary objective of this work was to investigate the efficiency of a crude SEP during fat shock loads, simulated through the periodic addition of dairy industry waste containing high fat concentrations to the feed stock of an activated sludge system, operated in continuous mode. RESULTS: The test bioreactor exhibited a higher average chemical oxygen demand (COD) removal efficiency than the control bioreactor (83% for control and 90% for test) and the fat accumulation in the biological flocs of the test bioreactor was 3.2 times lower than that in the control bioreactor. Turbidity was also lower in the effluent of the test bioreactor (123 and 66 FTU in control and test, respectively) and it had a shorter recovery time between shock loads, especially when the interval between loads was shorter than one month (biweekly and weekly shock loads). CONCLUSION: The addition of SEP during fat overloads in the reactor feed maintained efficient COD removal in the test bioreactor for 270 days without any operational problems. Copyright © 2008 Society of Chemical Industry  相似文献   
14.
Abstract:  This study proposes an alternate method for the analysis of beams with solid cross-section or built as a framed structure and subjected to transverse impact loads from an external striker. The procedure used in the analysis is a combination of two essential tools using pseudo-dynamic techniques. The method reported here involves only one degree of freedom for the structure modelling and assumes an elastic contact between an external striker and the beam structure, which in reality does not happen. As only one degree of freedom is considered in the analysis, some important limitations are inherent to the method proposed here. Essentially, there is the difficulty of modelling the displacement field associated with the transient structure behaviour accurately, as a consequence of fast-rate impact loads. Another difficulty faced by the method refers to a local structure behaviour associated with contact loads. The present method can deal with large displacements in transversely loaded beams associated to a collapse mechanism having a simple geometry and defined with precision from a single parameter. This ensures reasonable accuracy in the evaluation of the strain energy absorbing capacity of transversely impacted beam structures using a single degree of freedom model in a pseudo-dynamic procedure.  相似文献   
15.
基于高抗热震性能的陶瓷刀具材料的微观结构设计   总被引:1,自引:0,他引:1  
本文以现有的抗热震断裂和抗热震损伤的评价理论为基础,通过对材料中微裂纹的长度进行预测,从而实现了对陶瓷刀具材料的抗热震性能的微观结构设计。根据此理论对现有材料的抗热震性能的进行预测,预测结果与实际的测量结果相符,验证了该理论的正确性。  相似文献   
16.
压力计探测液面法探讨   总被引:2,自引:1,他引:1  
张洪 《油气井测试》2003,12(5):49-50
针对油田地质特征复杂,易结蜡,测试中易出现假液面等情况,为准确快速测得液面资料,提出压力计测试液面法。该方法可作为回声仪测液面方法的有效补充。  相似文献   
17.
Preexposing rats to the context facilitates subsequent contextual fear conditioning. This effect depends on the hippocampus (J. W. Rudy, R. M. Barrientos, & R. C. O'Reilly, 2002). The authors report that inactivating the basolateral region of the amygdala (BLA) by injecting muscimol, a GABAA agonist, before or after preexposure reduced this effect. In contrast, bilateral injections of anisomycin, a protein synthesis inhibitor, into BLA did not impair the consolidation of the context memory. However, when injected after fear conditioning, anisomycin impaired consolidation of both contextual and auditory-cue fear conditioning. Results are consistent with 2 ideas about the amygdala's contribution to memory: (a) It modulates memory formation in other regions of the brain, and (b) it is a storage site for cue-shock associations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
18.
空气预热器运行的好坏直接影响到加热炉的热效率 ,文章结合焦化装置加热炉空气预热器的使用、维修、改进等 ,论述了预热器存在的露点腐蚀问题。同时提出从设计、操作、设备等方面采取有效措施 ,保障预热器的长周期高效运行。  相似文献   
19.
激光对光学薄膜损伤的热冲击效应   总被引:11,自引:0,他引:11  
龚辉  李成富  王明利 《中国激光》1996,23(3):245-248
计算了薄膜在高功率脉冲激光作用下截面温度场和应力场分布。分析了热冲击在光学薄膜激光损伤中的作用,并用调Q1.06μm脉冲激光对ZrO2单层膜损伤,讨论了不同激光强度下薄膜截面温度场与应力场分布,揭示了热冲击在ZrO2单层膜损伤中的机理和过程。  相似文献   
20.
冲击过载批示器用于现代高技术兵器包装,可提高兵器使用可靠性,便于失效模式分析,提高兵器战是保障能力,具有重要的军事意义。根据六种不同结构原理的冲击过载指示器的振动、跌落试验,评价精度、可靠性、使用寿命、有效使用频率范围以及对振动的响应,得出冲击过载指示器的冲击响应加速度一时间特性曲线,为筛选可靠的指示器,自行研制性能稳定,精度可靠的军用冲击过载指示器提供试验评价依据。  相似文献   
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