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81.
The protocol for the measurement of ozone demand of water and the change in the dissolved ozone residual with time, using the Gas Ozone Test (GOT) was applied in monitoring water quality of two water treatment facilities. The change in the ozone concentration of water as a function of time was measured for each sample. The resulting half-time was correlated with the ozone dosage, although this parameter does not appear to be directly linked to the characteristics of the water samples studied. The change in the ozone concentration of water as a function of time and ozone dose, measured by the GOT, has direct applications in the sizing of ozonation reactors. 相似文献
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K. Bobzin N. Bagcivan M. Ewering S. Theiß 《Materialwissenschaft und Werkstofftechnik》2011,42(3):165-171
Over the last decade the interest in High Power Pulse Magnetron Sputtering (HPPMS) and High impulse Magnetron Sputtering (HiPIMS) has undergone a considerable increase. This is mainly due to the fact that several researchers have shown that in these processes a distinct increase of the ionization of deposition species is observable. However, there is only little known about the performance of these films with regard to applications. Recently Hovsepian et al. [1] and Bobzin et al. [2] presented cutting results of different films. Both authors show that films deposited using HPPMS or HiPIMS outperform state‐of‐the‐art coatings. Depending on the cutting process, besides hardness and adhesion also excellent impact behavior is required. Therefore this work deals with the impact behavior of (Ti,Al,Si)N which was deposited using HPPMS for the application in interrupted cutting process. The impact behavior of HPPMS coating under normal and tangential loads is analyzed. During impact tests number of impacts, loads and inclination angle of the samples with regard to the load direction are varied. (Ti,Al,Si)N shows an excellent endurance even at very high loads causing Hertzian stresses in the range of 10–13 GPa. At an inclination angle of 10° and an impact load of 100 N, which corresponds to app. 10 GPa initial Hertzian stress, no damage was observed after 800×103 impacts. 相似文献
85.
本文通过慢应变速度应力腐蚀试验,研究制冷压力容器用材16MnR、Q235-C、20R三种材料焊接接头在液氨中的应力腐蚀行为,评定其在液氨中发生应力腐蚀开裂的敏感性。 相似文献
86.
在制冷压力容器定期耐压试验中,针对不同制冷剂和冷冻润滑油制定了不同的耐压试验工艺,通过现场使用,证明所采用的试验方法是可行的,解决了国内制冷装置中压力容器的耐压试验难题。 相似文献
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结合国内外研究案例,深入分析了打印工艺、砂浆配合比等3D打印混凝土层间性能的影响因素。在此基础上,进一步探讨了3D打印混凝土层间强度的提高方式。同时总结了抗拉试验、抗剪试验、微观结构分析等层间强度测试方法并分析了各自优缺点。 相似文献
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Intermediate bulk containers (IBCs) for liquid dangerous goods require a ‘vibration test’ for type approval introduced in the United Nations Recommendations on the transport of dangerous goods. The test has to be performed as a repetitive shock test practically identical to the test procedure previously prescribed by the US Department of Transport. It is conceptually simple but has several drawbacks. The kinetics and dynamics of a bouncing IBC have been investigated by means of simple computational models. With increasing complexity, partially plastic impact, elastodynamic response and the excitation of internal vibrations not directly affected by the bounces can be covered. The latter is a model for the sidewall vibrations. The numerical results show that the control over the specimens' response is only partially defined in the test procedure. Chaotic movements at resonance are possible and must be suppressed by changing the test parameters, which is mostly left to the test engineer. Accordingly, it is not possible to interpret the test results with a sound relation to real transport vibration environment. Experimental results, however, suggest that vibration testing of IBCs improves safety because resonance effects in a frequency range excited by typical transportation loads exist. A more detailed numerical model is necessary for the assessment of the fatigue damage imposed on IBCs by the prescribed or alternative, more realistic test procedures. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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随着航天技术的不断发展,卫星功能日趋复杂,对卫星测控分系统的功能提出更高的需求,要求同时支持对地非相干扩频测控、中继测控、扩跳频测控及测量数传测控体制,对卫星测控系统地面测试平台多体制支持、通用化及自动化测试能力、可靠性提出了更高要求;本文研究了卫星多体制测控地面测试平台系统设计方法,采用了多通道测控地检通道复用、基于数据库的通用化配置及自动化测试技术,应用于某遥感卫星的地面测试,测试结果表明：该平台运行稳定,取得了良好的使用效果,满足了卫星多体制测控地面测试需求; 相似文献