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991.
围绕社会影响理论、煤矿安全氛围、外溢效应的内涵,通过资料分析和计量统计方法,甄别出社会影响动机主要包含3种动机、煤矿安全氛围主要包含7大因素、外溢效应主要包含3种方式,经分析制定社会影响动机下煤矿安全氛围对矿工生活的外溢效应调研问卷,对4个煤矿260名矿工展开调研。运用SPSS17.0和AMOS7.0,从以下2个方面进行比较研究:未考虑社会动机下煤矿安全氛围对矿工生活外溢效应进行潜变量路径分析;加入社会影响动机后煤矿安全氛围对矿工生活外溢效应进行回归分析。 相似文献
992.
A life cycle assessment was conducted using IMPACT2002+ to estimate the environmental impact of producing printing and writing paper, which is entirely made with wastepaper. To confirm and add credibility to the study, uncertainty analysis was conducted using Taylor series expansion. Printing and writing paper produced from wood pulp was assessed for comparison. Compared with the wood pulp contained scenario, printing and writing paper made from wastepaper represented environmental benefit on non-carcinogens, respiratory inorganics, global warming, and non-renewable energy categories. In both scenarios, the technologies significantly contribute to the potential impacts of non-carcinogens, respiratory inorganics, terrestrial ecotoxicity, global warming, and non-renewable energy. The influence of the technologies on the way other categories affect the environment was negligible. Improved efficiency in electricity consumption, decreased transport distance from raw material buyers to suppliers, and change in the end-life treatment of solid waste from landfill to incineration are the key factors in reducing the overall environmental impact. 相似文献
993.
滤袋使用寿命预计的必要性及其判据 总被引:1,自引:0,他引:1
论述了预测袋式除尘器用滤料使用寿命的意义,在评价现用预测方法利弊的基础上,提出以“设计寿命”为基础。以除尘器运行工况、抽样检测数据为依据,判断滤料“剩余寿命”的方法,经实践证明该方法是可行和有效的。 相似文献
994.
铁路运输是最安全的陆上交通方式,铁路投资相比较其他陆上运输方式可以带来更多的安全效益,对于铁路投资的安全效果一直未得到应有的重视,甚至往往被忽略,从而低估了铁路的投资效果和发挥的重大作用,因此,加强对铁路投资安全效果的研究具有十分重要的现实意义。为此,笔者在综合分析国外研究成果的基础上,定义了铁路投资的安全效果组成,将其区分为减少的资源消耗、减少的伤亡人员及其亲属的身心痛苦、减少的死亡者的生命价值3类,并重点分析了生命价值的测评方法,建立了一套符合中国国情并切实可行的铁路投资安全效果评价方法。 相似文献
995.
996.
甲基汞暴露不同时期对大鼠胚胎致畸作用的研究 总被引:1,自引:0,他引:1
本文应用全胚胎培养模型探讨了致畸物甲基汞(04μG/ml)在器官形成早期暴露不同时期后,对大鼠胚胎生长发育的影响。结果显示早期暴露6h,畸胎发生率为333%;12h,绝大多数反映胚胎生长发育和器官形态分化的指标埴均明显降低且50%的胚胎出现多种畸形表现,例如,神经管未闭、心包积液及脑部形态异常等;暴露24h和48h,甲基汞对胚胎发育的抑制作用及诱发的畸胎率匀与12h的结果类似(p>005);但在晚期暴露12h,未见胚胎发育异常。结果提示体外培养胚胎对甲基汞的敏感时期约在1—12h这一期间 相似文献
997.
998.
ABSTRACT Mexico faces multiple water quality challenges, both in terms of the water supplied to the population as well as surface and underground water sources. Problems with drinking water supply affect the population in diverse ways, from associated health risks to high levels of intermittency in service to the poor perception of the quality of piped water – leading to high levels of bottled water consumption. In this text we explore the issue of drinking water quality in three contexts in the state of Jalisco: in Guadalajara, the state’s main urban area, in the peri-urban municipality of El Salto, and in the mid-sized city of San Juan de los Lagos. Our analysis explores drinking water regulations, the water quality monitoring undertaken by state and local authorities, access to information, as well as the actions and perceptions of water service providers. Looking at cases of indirect reuse of wastewater as well as groundwater sources with high levels of fluoride and arsenic, we argue that the foregrounding of water quality is key to illuminating social inequalities in access to water and in teasing out power relations prevailing in current hydrosocial regimes. We conclude that this hydrosocial cycle of drinking water is characterised by prioritising access to water for economic actors, facilitated by lax regulations and minimal enforcement, as well as by the systematic neglect by government authorities at all levels of the protection of watersheds and aquifers, and of water quality issues generally. 相似文献
999.
Otis W. Tempter 《Journal of the American Water Resources Association》1973,9(2):273-283
ABSTRACT Scientists usually regard all water as merely passing through, but in different phases of, the endless hydrologic cycle. The law divides water in the cycle into several different classes. Each is treated separately and generally without consideration of interconnections existing within the cycle. Different rules of law have arisen concerning the ownership and use of each legal class. Under Texas law several classes of surface and ground water are recognized, and weather modification efforts bring yet another class, atmospheric moisture, under consideration. It is instructive to follow water moving through the hydrologic cycle in the Nueces River basin, Texas, as a framework for discussing the substantial interconnections between the various legal classes of water and the difficulties that arise from attempts to apply different rules of law to each class. Strictures imposed by Texas water law can seriously interfer with coordinated, efficient use and management of water resources, as evidenced by the Nueces River basin. Well-recognized, existing water rights in the several phases of the hydrologic cycle make change of these institutional constraints difficult to achieve. 相似文献
1000.
ABSTRACT: Maintenance of the more than 24 million septic tanks in the U.S. requires removal and disposal of septage. Disposal options include application to agricultural lands where the nutrients and organic matter can provide soil benefits. However, pathogens and contaminants are also contained in septage. An extensive search turned up very few data on septage quality, and those reveal high variability. The data used by the U.S. Environmental Protection Agency (EPA) in developing regulations had the lowest metal concentrations among the nine data sets that could be compared. Based on these data, EPA assumed that septage could be applied to agricultural land for more than 100 applications before reaching unacceptable cumulative loading of metals. They thus did not establish federal standards for metals in septage, and no monitoring is required under federal rules governing septage disposal. Analysis of the nine data sets we found showed that field site life would be reached in less than 100 applications for most septage and cumulative loading limits established by EPA for sewage sludges will be exceeded in 16 applications for some septage as opposed to the 100 application estimate used by EPA. Determination of acceptable cumulative loading depends on numerous technical and policy considerations. All septage sources reached the more restrictive loading limits such as those established by the New York State Department of Environmental Conservation (NYSDEC) and the recommendations in Cornell publications in less than 100 applications. In one case the cumulative limit for copper was exceeded in a single application. These findings suggest additional data are needed on septage quality and that the federal and state agencies responsible for regulating application of septage to agricultural land should reassess their standards. 相似文献