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61.
辐射防护的生物学基础--辐射生物效应 总被引:7,自引:1,他引:7
人类必须研究电离辐射的生物效应,以保护其自身及其它物种免受电离辐射的有害影响,同时在应用中最大限度地获取利益,辐射生物效应,作为辐射防护的生物学基础,一直受到国内外辐射防护界的极大关注。本文就辐射防护密切相关的辐射随机效应,辐射致癌概率,小剂量照射效应及组织权重因子等进行简要讨论。 相似文献
62.
吴君钦 《自动化与信息工程》2003,24(4):34-36
本文详细分析了多串行接口控制器(卡)共享一个8259中断号时遇到的中断阻塞的问题,并讨论了如何在多串口卡的软件处理程序中解决共享中断所产生问题。 相似文献
63.
针对用极大似然方法和限制极大似然方法进行混合模型的参数估计,设计并实现了随机效应的协方差矩阵和观测误差的协方差矩阵及其导数信息的切实可行的存储方案。 相似文献
64.
电力电容器真浸工艺是电容器制造技术中的关键工艺,优良的真浸设备是合理真空工艺制定的基础.为此,西容公司引进国外全自动真空浸渍及油处理设备,为我国电力电容器制造工艺的提高又提供了新的途径,通过了解该设备的性能和特点为提高国内电容器浸渍工艺技术提供参考依据. 相似文献
65.
爆破对贵定石灰石露天矿边坡稳定性的影响 总被引:1,自引:0,他引:1
黄俊 《武汉化工学院学报》1997,19(2):45-49
从对贵定矿爆破地震效应进行观测及数据分析,计算出爆破等效静力系数ke,进而讨论了ke对该矿边坡稳定性的影响,为边坡的维护提供了依据. 相似文献
66.
67.
In this paper, a brief review of the experimental facts associated with the crack growth delay period following a tensile overload is given. In the retardation process, crack closure is considered to play a dominant role. A scenario for the two crack opening processes which develop as a fatigue crack penetrates the overload plastic zone is presented. This scenario deals with the effect of specimen thickness on the crack opening processes. Consideration is given to the delay distance and to the minimum crack growth rate. A method of analysis for the determination of the number of delay cycles following an overload is then developed. Finally the method of analysis is used to compare with recent experimental results. 相似文献
68.
Effect of Magnetic Field on the Deposition of Transparent Diamond-Like Carbon ( DLC ) Films by RF-PCVD 总被引:3,自引:0,他引:3
In order to deposit transparent and hard DLC films, magnetic field was introduced to enhance the plasma density of radiofrequency plasma chemical vapor deposition (RF-PCVD). In this paper, the configuration and computation of external magnetic field B are introduced. The restriction effect of magnetic field B on the charged particles and the effect of magnetic field B on the primary parameters-nonindependent power Pf and self-bias Uz were also studied. The mechanism of how magnetic field B affects self-bias Uz was analyzed. 相似文献
69.
Hot Dip Aluminized Coatings with different thickness were prepared on Q235 steel in aluminum solutions with different temperature for certain time. Through tensile tests and in-situ SEM observations, the effect of the coating's microstructure on the tensile strength of the samples was studied. It was disclosed at certain aluminum solution temperature,transaction layers mainly composed of Fe2 Al5 phase got thicker with time prolonging, and this changed initial crack's extending direction from parallel with to vertical with stretching direction. The change in crack direction decreased tensile strength of samples, thus made the coating easy to break. It was concluded that the existence of thick Fe2 Al5 phase layer was the basic reason for the lowering of tensile strength of the coating. 相似文献
70.
Simon effects might partly reflect stimulus-triggered response activation. According to the response-discrimination hypothesis, however, stimulus-triggered response activation shows up in Simon effects only when stimulus locations match the top-down selected spatial codes used to discriminate between alternative responses. Five experiments support this hypothesis. In Experiment 1, spatial codes of each response differed by horizontal and vertical axis position, yet one axis discriminated between alternative responses, whereas the other did not. Simon effects resulted for targets on discriminating axes only. In Experiment 2, both spatial axes discriminated between responses, and targets on both axes produced Simon effects. In Experiment 3, Simon effects resulted for a spatial choice-reaction task but not for a go/no-go task. Even in the go/no-go task, a Simon effect was restored when a two-choice reaction task preceded the go/no-go task (Experiment 4) or when participants initiated trials with responses spatially discriminated from the go response (Experiment 5). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献