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81.
构建煤矿职业安全卫生管理体系   总被引:2,自引:0,他引:2  
安全生产是煤矿企业的头等大事。根据煤矿企业的实际特点 ,分析了煤矿安全生产管理的现状、特点和煤矿建立职业安全卫生管理体系的注意事项。讨论了建立煤矿职业安全卫生管理体系的步骤和方法  相似文献   
82.
矿井主通风机叶轮磨损失效的评价   总被引:1,自引:0,他引:1  
矿井主通风机叶轮严重磨损威胁着矿井安全生产 ,研究主通风机叶轮磨损和正确地评价叶轮的磨损失效 ,对煤矿安全生产具有重大的现实意义。应用气—固两相流动理论分析了主通风机叶轮的磨损部位 ,结论与现场叶轮的实际磨损相吻合。提出了叶轮磨损过程的 3个阶段。利用材料磨损理论分析了主通风机叶轮磨损机理 ,得出了叶轮磨损是以气体动力学磨料的冲蚀磨损为主 ,低应力擦伤型磨料磨损、腐蚀磨损为辅的结论。依据国家标准 ,结合矿井主通风机工作特点 ,从安全角度提出了矿井主通风机叶轮磨损永久失效的判据 ,并给出了判定标准。  相似文献   
83.
陶庄煤矿矿震灾害与防治   总被引:4,自引:1,他引:4  
马志峰 《灾害学》2002,17(4):60-63
本文通过对陶庄煤矿矿区地质构造及矿震分布特征的分析,探讨了矿震的发生条件及其机理,提出了矿震与天然地震的关联性,阐明了矿震的前兆特征及防治措施。  相似文献   
84.
The southern Africa crisis represents the first widespread emergency in a region with a mature HIV/AIDS epidemic. It provides a steep learning curve for the international humanitarian system in understanding and responding to the complex interactions between the epidemic and the causes and the effects of this crisis. It also provoked much debate about the severity and causes of this emergency, and the appropriateness of the response by the humanitarian community. The authors argue that the over-emphasis on food aid delivery occurred at the expense of other public health interventions, particularly preventative and curative health services. Health service needs were not sufficiently addressed despite the early recognition that ill-health related to HIV/AIDS was a major vulnerability factor. This neglect occurred because analytical frameworks were too narrowly focused on food security, and large-scale support to health service delivery was seen as a long-term developmental issue that could not easily be dealt with by short-term humanitarian action. Furthermore, there were insufficient countrywide data on acute malnutrition, mortality rates and performance of the public health system to make better-balanced evidence-based decisions. In this crisis, humanitarian organisations providing health services could not assume their traditional roles of short-term assistance in a limited geographical area until the governing authorities resume their responsibilities. However, relegating health service delivery as a long-term developmental issue is not acceptable. Improved multisectoral analytical frameworks that include a multidisciplinary team are needed to ensure all aspects of public health are dealt with in similar future emergencies. Humanitarian organisations must advocate for improved delivery and access to health services in this region. They can target limited geographical areas with high mortality and acute malnutrition rates to deliver their services. Finally, to address the underlying problem of the health sector gap, a long-term strategy to ensure improved and sustainable health sector performance can only be accomplished with truly adequate resources. This will require renewed efforts on part of governments, donors and the international community. Public health interventions, complementing those addressing food insecurity, were and are still needed to reduce the impact of the crisis, and to allow people to re-establish their livelihoods. These will increase the population's resilience to prevent or mitigate future disasters.  相似文献   
85.
A 6-month greenhouse pot trial was performed, aimed at screening appropriate Sesbania species for remediation of Pb/Zn and Cu mine tailings. Performances of young seedlings of four Sesbania species (S. cannabina, S. grandiflora, S. rostrata, and S. sesban) were compared with and without inoculation of rhizobia. Seedlings were planted in two types of tailings amended with garden soil or garden soil mixed with river sediment. The results indicated that inoculated plants generally produced a higher biomass than samples without inoculation. Pb/Zn mine tailings containing rather high concentrations of total and water-soluble Cu, Pb, and Zn were toxic to plant growth compared with Cu mine tailings, according to the growth performance of the four species. Sesbania sesban and S. rostrata showed superior growth performance, compared to the other two species. Thus, they can serve as pioneer species to modify the barren environment, by providing organic matter and essential nutrients such as nitrogen, upon decomposition, in a relatively short period of time. This is especially true for S. rostrata, which is an annual plant that forms both stem and root nodules. However, a longer-term field trial should be conducted to investigate if superior species can beneficially modify the habitat for the growth of subsequent plant communities.  相似文献   
86.
Hammond L  Maxwell D 《Disasters》2002,26(3):262-279
During 1999-2000, Ethiopia was brought to the edge of a major disaster, with some 10 million people estimated to be in need offood assistance at the height of the crisis. A repeat of the catastrophic famine of 1984-5 was avoided, but the numbers of people affected, the loss of life and the destruction of livelihoods made this one of the most serious crises in the Horn of Africa in the past 15 years. The humanitarian community has been slow to recognise the lessons of 1999-2000, and there have been surprisingly few attempts to conduct a serious, post-event evaluation of the overall crisis and response. The label famine averted' seems to summarise the crisis to the satisfaction of most parties involved. This paper reviews the crisis, the events that led up to it and the response effort. It examines thefactors that contributed to making this crisis so serious, in order to draw conclusions and note issues that are relevant to current thinking about disaster preparedness and response - in Ethiopia and elsewhere. Some of the lessons learned from the 1999-2000 crisis are not new. However, the veryfact that mistakes have been repeated should be a lesson to the humanitarian community.  相似文献   
87.
Mineralogical compositions and their spatial distributions are important initial conditions for reactive transport modeling. However, popular Kd-based "reactive" transport models only require contaminant concentrations in the pore fluids as initial conditions, and minerals implicitly represent infinite sources and sinks in these models. That situation results in a general neglect of mineralogical characterization in site investigations. This study uses a coupled multi-component reactive mass transport model to predict the natural attenuation of a ground water plume at a uranium mill tailings site in western USA. Numerous ground water geochemistry data are available at this site, but mineralogical data are sketchy. Even given the well-defined pore fluid chemistry, variations of secondary mineral species and mineral abundances in the aquifer resulted in significantly different modeling outcomes. Results show that the amount of calcite in the aquifer determines the distances of plume migration. The possible presence of jurbanite, an aluminum sulfate phase, can store acidity temporarily but cause more severe contamination on a later date. The surfaces of iron oxyhydroxides can store significant amounts of sulfate and protons and serve as a second source for prolonged contamination. These simulations under field conditions illustrate that mineralogical compositions are an essential requirement for accurate prediction of contaminant fate and transport.  相似文献   
88.
降低地下矿深孔爆破落矿大块率的技术措施   总被引:2,自引:0,他引:2  
降低深孔爆破落矿大块率是矿山凿岩中的一个重要课题。笔者对地下矿深孔爆破落矿中大块产生位置及原因进行分析;探讨在炸药单耗、孔网布置、装药结构、堵塞长度、微差间隔、起爆方式等方面对其产生影响的规律;提出地下矿深孔爆破落矿中通过优化爆破参数降低大块率的技术措施。该优化技术措施主要有:减少地质构造对深孔落矿的影响,合理确定炸药单耗的方法,使用大孔距小抵抗线落矿技术,采用多种装药结构技术,采用多排微差起爆技术,加强深孔的施工管理和加强爆破施工的现场管理。这些措施在工程实践中获得了良好的应用效果。  相似文献   
89.
对安全生产监督脆弱是造成我国企业安全生产状况十分严峻的重要原因,必须采取相应的措施予以解决。笔者从博弈的视角出发,应用博弈论的相关理论分析现有体制和制度框架下我国企业安全生产的监督效果,提出了一些解决的措施。笔者认为,要改善我国企业安全生产状况的根本出路在于制度创新和激励监督者的“努力”行为。必须实施制度创新,充分提高企业职工自觉进行安全监督的积极性;加重对“违规”行为的处罚力度,只能在短期内减少其“违规”的概率,而不会消除或降低“违规”行为的发生。正确的做法应该是从长远看,加强对监督者“努力”行为的激励力度,才能消除或降低“违规”行为的发生。  相似文献   
90.
煤矿本质安全特征及管理方法研究   总被引:3,自引:9,他引:3  
分析国内煤矿本质安全管理研究现状及存在问题,进一步讨论煤矿本质安全的内涵。探讨近年来我国煤矿事故发生的致因与根源,指出人的行为安全是我国煤矿本质安全的主要特征。通过研究我国煤矿事故的控制管理,选择事故率作为我国煤矿本质安全判别的参考标准;分析我国煤矿生产的现状与差异,提出了对我国煤矿的本质安全性进行分类判别的思想;从深入开展煤矿安全管理理论研究、加强煤矿安全管理立法、建立煤矿安全管理标准和有效组织机制等方面提出了实现煤矿本质安全的管理策略。  相似文献   
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