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91.
所提出的磁光旋转器是由Verdet常数小的普通ZF-6小玻璃片和带有窄缝隙的小电磁铁组成,当电磁铁线圈的功耗为10W时,可得到21°的法拉第旋转。  相似文献   
92.
93.
对基于Visual Basic 6.0开发的自动控制原理考试系统的系统结构做了阐述,并简要介绍了该系统的设计思想、主要功能及实现方法。  相似文献   
94.
Quenching with gases rather than oil or other liquid media has the advantages of reducing the risks concerning health and environment, while simultaneously homogenizing the quenching results and minimizing distortion due to a wide range of possible process parameter variations and the pure convective heat transfer. In this contribution, a coupled solution for increasing homogenization of quenching results within high pressure gas quenching will be presented. In the first stage, an experimental test facility was set up for flow investigations and in the second stage a numerical simulation model was generated. The numerical and experimental results of the flow through the chamber were compared for several boundary conditions. Finally, after complete verification of the simulation, the model may be used to assist in parameter variation for optimization of homogeneous high pressure gas quenching.  相似文献   
95.
This paper is the second dealing with measurement-related uncertainties of overcoring data undertaken at the Äspö Hard Rock Laboratory and focuses on the biaxial test data from CSIRO HI overcore samples. The first paper dealt with measurement-related uncertainties in connection with the overcoring phase [1].The uncertainties identified in connection to biaxial tests of CSIRO HI overcore samples include too large applied pressures and poor sampling frequency. At the Äspö HRL, the results yield that most overcore samples fractured during biaxial testing, meaning that a significant part, 56%, of available strain gauge combinations were removed from calculations of the elastic parameters. Remaining strain gauge combinations indicate average values of 62±5 GPa for Young's modulus and 0.25±0.01 for Poisson's ratio, which are considerably lower than previously published values [2–5], and are in good agreement with results from biaxial tests on Borre Probe overcore samples [6–10]. The stress calculations were obtained from re-analyzed elastic parameters and strains, and show primarily a reduction in stress magnitudes. Overall, the stress field obtained with different stress measurement methods and its variation with depth is now quite well resolved. The overcoring data suggest that the principal stresses are inclined with a vertical component dipping about 65° from the horizontal over the investigated rock volume (140–420 m depth). This is interpreted as a result of influence from the sub-vertical NE-2 Fracture Zone that divides the stress data into two stress domains [11], although it may also be an artefact because the σ2- and σ3-magnitudes are of the same order of magnitude.  相似文献   
96.
燃气管网模拟分析软件的开发与应用   总被引:1,自引:0,他引:1  
介绍了以牛顿节点法模型为基础、应用VB语言开发管网分析软件的思路和方法,开发的软件具有实用性、稳定性和易操作性.结合实例,说明了软件在天然气转换方案选择、事故工况分析等领域的应用.  相似文献   
97.
Polymer blends based on polyolefins are of a great interest owing to their broad spectrum of properties and practical applications. However, because of poor compatibilities of components, most of these systems generally exhibit high interfacial tension, a low degree of dispersion and poor mechanical properties. It is generally accepted that polypropylene (PP) and nylon 6 (N6) are not compatible and that their blending results in poor materials. The compatibility can be improved by the addition of a compatibilizer, and in this study PP was functionalized by maleic anhydride (MAH) in the presence of an optimized amount of dicumyl peroxide (DCP). The reaction was carried out in the molten state using an internal mixer. Then, once the compatibilizer polypropylene‐graft‐maleic anhydride (PP‐g‐MAH) was prepared, it was added at various concentrations (2.5–10 wt%) to 30/70 glass fibre reinforced N6 (GFRN6) PP, and the mechanical properties were evaluated. It was found that the incorporation of the compatibilizer enhanced the tensile properties (tensile strength and modulus) as well as the Izod impact properties of the notched samples. This was attributed to better interfacial adhesion as evidenced by scanning electron microscopy (SEM). The optimum in these properties was achieved at a critical PP‐g‐MAH concentration. Copyright © 2005 Society of Chemical Industry  相似文献   
98.
This study prospectively examined the relationship between religious attendance, interleukin-6 (IL-6) levels, and mortality rates in a community-based sample of 557 older adults. Attending religious services more than once weekly was a significant predictor of lower subsequent 12-year mortality and elevated IL-6 levels (> 3.19 pg/mL), with a mortality ratio of .32 (95% confidence interval [CI] = 0.15,0.72; p  相似文献   
99.
Fault-based side channel cryptanalysis is very effective against symmetric and asymmetric encryption algorithms. Although straightforward hardware and time redundancy based concurrent error detection (CED) architectures can be used to thwart such attacks, they entail significant overhead (either area or performance). In this paper we investigate two systematic approaches to low-cost, low-latency CED for symmetric encryption algorithm RC6. The proposed techniques have been validated on FPGA implementations of RC6, one of the advanced encryption standard finalists.  相似文献   
100.
6to4与ISATAP技术相结合的IPv6网络实现   总被引:2,自引:0,他引:2  
在IPv4向IPv6过渡期间,多种过渡技术可以互相支持、互相组合使用,以达到互利互助。简要介绍了其中2种隧道技术:6to4技术和ISATAP技术,提出了1种基于两者结合的新型实验网络的实现方案。具体讨论了在Linux下如何组建这种新型实验网络平台,详细阐明了如何配置IPv6主机以及双栈路由器,为IPv4过渡到IPv6提供1个可行的方案。  相似文献   
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