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41.
40000m~3/h空分设备主换热器的设计及制造   总被引:1,自引:0,他引:1  
通过对进口 4 0 0 0 0m3 /h空分设备主换热器进行结构分析及对比模拟计算 ,用国产传热翅片进行设计、采用真空钎焊工艺制造的主换热器 ,经并网运行 ,设计指标优于原空分设备 ,为今后成套大型空分设备板翅式换热器国产化设计、制造创造了条件。  相似文献   
42.
本文探讨了高速钢在高温形变过程中碳化物析出的行为及奥氏体组织状态对析出的影响。用透射电镜和扫描电镜分析了不同热处理状态奥氏体的组织结构,分析了高温形变过程中碳化物析出的部位,颗粒尺寸及形态。试验表明, 碳化物主要在奥氏体的缺陷处呈点状和点列状析出,大小为20mμ。处于回复状态的奥氏体缺陷诱发碳化物析出,析出碳化物钉札缺陷阻止再结晶进行。当再结晶驱动力较大时,由于动态再结晶充分发展,使缺陷大量消除,碳化物析出显著地减少。  相似文献   
43.
[Correction Notice: An erratum for this article was reported in Vol 20(2) of Canadian Journal of Behavioural Science Revue canadienne des Sciences du comportement (see record 2007-09831-001). The abstract accompanying the original article was incorrect; the correct abstract (in French) is presented in the erratum.] We know little about individuals who are declared unfit to stand trial and/or not guilty by reason of insanity. The few existing studies are characterized by methodological weaknesses, notably by short follow-up periods and a lack of external validity. The present investigation, which aims to evaluate and explain readmissions that occurred during a seven- to nine-year period, corrects only some of these weaknesses. Sixty-one per cent of the subjects were rehospitalized during the period of study. It proved difficult to identify the factors associated with readmission. However, males with a diagnosis of schizophrenia and who had committed violent crimes were found the most likely to be readmitted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
44.
论文介绍了一种针对铁水鱼雷罐车铁水液位检测的较为可行的低成本方案。采用车上间接称重、远红外非接触传输信号方式,解决了对移动铁水罐车进行实时监测的难题。  相似文献   
45.
节能降耗提高矿山效益   总被引:1,自引:0,他引:1  
节能降耗是每一个矿山提高经济效益的有效途径。我们采取提高球磨机处理能力,降低单耗;利用“分时计价”政策,采用“避峰作业”;使用新设备等措施节能降耗,提高矿山经济效益。  相似文献   
46.
An increasing number of avian flu cases in humans, arising primarily from direct contact with poultry, in several regions of the world have prompted the urgency to develop pandemic preparedness plans worldwide. Leading recommendations in these plans include basic public health control measures for minimizing transmission in hospitals and communities, the use of antiviral drugs and vaccination. This paper presents a mathematical model for the evaluation of the pandemic flu preparedness plans of the United States (US), the United Kingdom (UK) and the Netherlands. The model is used to assess single and combined interventions. Using data from the US, we show that hospital and community transmission control measures alone can be highly effective in reducing the impact of a potential flu pandemic. We further show that while the use of antivirals alone could lead to very significant reductions in the burden of a pandemic, the combination of transmission control measures, antivirals and vaccine gives the most 'optimal' result. However, implementing such an optimal strategy at the onset of a pandemic may not be realistic. Thus, it is important to consider other plausible alternatives. An optimal preparedness plan is largely dependent on the availability of resources; hence, it is country-specific. We show that countries with limited antiviral stockpiles should emphasize their use therapeutically (rather than prophylactically). However, countries with large antiviral stockpiles can achieve greater reductions in disease burden by implementing them both prophylactically and therapeutically. This study promotes alternative strategies that may be feasible and attainable for the US, UK and the Netherlands. It emphasizes the role of hospital and community transmission control measures in addition to the timely administration of antiviral treatment in reducing the burden of a flu pandemic. The latter is consistent with the preparedness plans of the UK and the Netherlands. Our results indicate that for low efficacy and coverage levels of antivirals and vaccine, the use of a vaccine leads to the greatest reduction in morbidity and mortality compared with the singular use of antivirals. However, as these efficacy and coverage levels are increased, the use of antivirals is more effective.  相似文献   
47.
主要阐述了某型飞机EBW飞行试验台的LabWindows/CVI实现。在分析EBW组成及信号交联关系的基础上,设计了PCI总线结构的系统硬件;提出了测试库与测试引擎相结合的编程方法,并着重阐述了测试引擎的实现方法。  相似文献   
48.
The catalytic activity of fresh Pd and Pt catalysts supported on γ-alumina in the complete oxidation of CH4 traces under lean-burn conditions was studied in the presence or the absence of water or H2S. Steam-aged catalysts were also studied in order to simulate long-term ageing in real lean-burn natural gas fuelled vehicles (NGVs) exhaust conditions. Without water or H2S added to the feed, Pd catalysts exhibit a superior catalytic activity in methane oxidation compared to Pt ones, whatever the catalysts were fresh or aged. The addition of 10 vol.% water vapour to the feed strongly affects the activity of the fresh Pd catalyst, thus being only slightly more efficient than the fresh Pt one. H2S has a strong poisoning effect on the catalytic activity of Pd catalysts, while Pt catalysts are more resistant. The fresh H2S-poisoned Pd/Al2O3 catalyst was studied by TPD in O2/He. Poisoning species decompose above 873 K as SO2 and O2 in relative concentrations consistent with the decomposition of surface sulphate species. However, a treatment in O2/He at temperatures as high as 923 K does not allow the complete regeneration of the catalytic activity of H2S-poisoned Pd/Al2O3. A mechanism involving the poisoning of PdO by sulphate species is proposed. Different diffusion processes by which these sulphate species can migrate back and forth between PdO and the support, depending on the experimental conditions, are suggested.  相似文献   
49.
童晓阳  刘恒 《计算机工程》2003,29(20):188-190
研究了公安网上追逃系统的体系结构和系统的程序流程,阐述了ASP COM 后台比对服务的3层B/S模式面像网上比对的实现方法,最后给出系统的性能指标和特点。  相似文献   
50.
袁继强 《山西建筑》2004,30(17):82-83
介绍了免振捣自密实混凝土的特点和质量控制措施,结合某小区自密实混凝土工程应用实例,阐述了该项施工技术,其经济和社会效益良好,提出了进一步发展该技术的若干设想。  相似文献   
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