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排序方式: 共有2094条查询结果,搜索用时 15 毫秒
61.
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
62.
63.
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
64.
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
65.
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
66.
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
67.
The main purpose of this paper is to investigate numerically the effects of solidification on the heat transfer characteristics of the liquid metal layer, for use in accident analyses. The situation is very similar to an overlying liquid melt pool that could be fooned in the reactor lower head during the late phase of a severe nuclear accident. Based on a computational model, MPCOOL, the numerical predictions were then assessed through a comparison with the experimental data that was obtained with various boundary temperature conditions and geometrical aspect ratios, especially for the Ra-Nu relationship. For the cases with solidification, the results of the comparison show that(a) the computational model does show a good agreement with heat transter rates inferred from the experimental data, with a few exceptions at the Ra numbers which suggest a turbulent transport; and also (b) the computational model underpredicts the heat transfer rates by about 6% than that inferred from the experimental data when it is integrally evaluated with the Ra-Nu correlation. The foregoing results are mainly due to the currently limited applicability of the computational model up to the laminar-to-turbulence transition flows and its application to the turbulence flows because it is always subjected to a model uncertainty between the laminar and turbulence. Next, an additional comparison for the cases with and without solidification was made to examine the effects of the solidification on the energy partition within the liquid metal layer and its effects on the directional heat transfer rates. The results of the comparison show that the computational model for the case without solidification predicts higher heat transfer rates by about 15% than when solidification is included, but there isn't any experimental data that directly supports this trend. 相似文献
68.
300MW汽轮发电机组径向可倾瓦轴承性能研究 总被引:2,自引:1,他引:2
本文详细分析了热弹变形对轴承性能的影响,结果表明热变形对轴承性能的影响较小,而热弹变形对轴承性能的影响较大。 相似文献
69.
HALL漏磁探伤传感器的研制 总被引:3,自引:0,他引:3
基于HALL效应和电磁无损检测原理,对HALL漏磁探伤传感器的磁场信号形成与磁场信号测量进行了分析,在此基础上对传感器的整体结构设计进行了介绍。 相似文献
70.
柴油机HCCI燃烧特点及影响因素分析 总被引:3,自引:0,他引:3
介绍了发动机均质充量压缩着火(HCCI)燃烧的概念和特点,更进一步分析了柴油机HCCI燃烧的特点.以及影响柴油机HCCI燃烧的一些重要因素,如混合气形成方式、进气温度、负荷、EGR、气门正时、压缩比等的影响. 相似文献