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1.
徐红  刘飚 《干旱环境监测》1991,5(4):208-209,213
本文对某铀矿职业工人和非职业工人头发中的总β、总α放射性水平和铀、钍含量进行了分析测定.结果表明,该矿工人体内铀和钍的蓄积量均在正常放射性本底水平范围内,从头发中检验未观察到工人体内铀、钍放射性水平有明显的升高.  相似文献   
2.
针对沈阳市地铁疏干水利用的现状,综合考虑沈阳市的实际情况,总结出地铁疏干水利用的几种方法,主要包括作为运河、湖泊的补换水源,用于修复、重建湿地,农业灌溉用水以及作为水源热泵的水源等。提出沈阳市地铁疏干水利用的指导思想和法律保障。  相似文献   
3.
Transportation system has contributed significantly to the development of human civilization; on the other hand it has an enormous impact on the ambient air quality in several ways. In this paper the air and noise pollution at selected sites along three sections of National Highway was monitored. Pakistan National Highway Authority has started a Highway Improvement program for rehabilitations and maintenance of National highways to improve the traffic flows, and would ultimately improve the air quality along highways. The ambient air quality and noise level was monitored at nine different locations along these sections of highways to quantify the air pollution. The duration of monitoring at individual location was 72 h. The most of the sampling points were near the urban or village population, schools or hospitals, in order to quantify the air pollution at most affected locations along these roads. A database consisting of information regarding the source of emission, local metrology and air quality may be created to assess the profile of air quality in the area.  相似文献   
4.
对宜昌市沮漳河流域当阳段的水环境进行了调查和评价。通过区域自然环境、社会经济发展、水体功能区、水环境容量等分析以及多个断面数据的监测,表明沮漳河流域当阳段水环境质量不能满足Ⅲ类水体功能区要求,主要超标因子为高锰酸盐指数、NHrN、BOD5、TP、石油类,主要受沿岸工业废水、生活污水及农业面源污染所致。  相似文献   
5.
系统分析了辽河流域近十年社会经济和水污染物排放之间的关系,基于污染物排放强度和人均GDP指标,建立辽河流域COD和氨氮环境学习曲线;结合情景分析法预测在现有治污水平下,辽河流域未来水污染物排放趋势及水环境压力。结果表明,辽河流域水环境压力巨大。根据辽河流域污染治理中存在的实际问题,提出新时期的污染治理模式。  相似文献   
6.
当前我国水资源供需矛盾日益加剧,实现中水利用是节约水资源的一条有效途径.通过分析中水水源、MBR处理技术及中水用途,结合一个高校实例,进行经济效益分析,并对建设中水回用系统的可行性进行论证.经计算可得效益费用比达到2.38,经济效益是非常明显的,具有实际的参考价值.中水回用不仅节约了水资源而且也产生了明显的经济效益,是城市发展的趋势.  相似文献   
7.
为了增加多壁碳纳米管(multiwall carbon nanotubers,MWNTs)对水中Cd2+的吸附量,使用混酸对多壁碳纳米管进行氧化处理,采用红外光谱进行结果表征,并探讨了吸附时间、pH值和MWNTs的使用量、Cd2+的浓度及干扰离子对镉离子吸附的影响。结果表明,吸附时间为1.5 h、pH为5.3、吸附效果最佳,随MWNTs量的增加Cd2+去除量增加,共存的阳离子会降低对Cd2+的吸附效果,对Cd2+的吸附符合Longmuir吸附定律。研究同时表明,pH小于2时Cd2+能容易从碳纳米管上解吸。初步探讨了Cd2+吸附机制。  相似文献   
8.
Biosphere greenhouse gas (GHG) management consists of preserving and enhancing terrestrial carbon pools and producing biomass as a fossil fuel substitute. The discussion of this topic has focused primarily on carbon-accounting and project-level issues, particularly relating to carbon sequestration as a source of emissions credits under the Kyoto Protocol. While international consensus on these matters is needed, this paper argues that an important domestic policy agenda also deserves attention. National policies for biosphere GHG management are necessary to bring about large-scale changes in land-use, forestry, and agricultural practices and can address some of the technical and policy issues that have proven to be particularly problematic from carbon-accounting and project-level perspectives. These policies should minimize land-use and resource-management conflicts, account for collateral benefits, and ensure institutional compatibility with existing resource-management regimes. Issues relating to project permanence, leakage, and transaction costs should also be addressed. A range of policy instruments should be used and biosphere GHG management should be one component of an integrated approach to environmental and resource management. Countries promoting biosphere GHG management as an important element of their climate change strategies should be developing these domestic policies to complement international negotiations and to demonstrate that carbon sequestration and biomass production can make an effective contribution to the stabilization of atmospheric GHG concentrations.  相似文献   
9.
ABSTRACT

The impacts of extreme weather events, causing severe storms and wildfires, cascade across administrative borders within a country, challenging the steering capacity of governance networks at different political scales. This paper examines how accountability and risk were constructed and negotiated in the aftermath of Sweden’s largest wildfire. It draws on results from an interview study with executives of organizations and landowners involved, and an analysis of government reports about the wildfire’s cause and consequences. Although the fire was human-caused, public administrative bodies paid considerable attention to the local emergency services and their poor handling of the wildfire, caused by lack of knowledge of forest fire behavior. The study confirms many of the challenges associated with governance networks. It finds that issues about who to hold accountable, in what forum and for what issue are not fully addressed, being overwhelmed by demands for better knowledge of forest fire prevention and improved coordination and collaboration. To conclude, the paper calls for a better-informed public administration, forest sector and interrelated networks that take responsibility for their actions or lack thereof.  相似文献   
10.
Increasingly commonplace in cities, extreme heat events introduce multi-stress vulnerability, affecting people’s health and well-being, financial situation, mobility, social relations, and access to basic services. Planning to reduce heat vulnerability has become part of government business and to some extent community-level responses, cutting across a number of sectors including public health, emergency management, social services, critical infrastructure, and housing. This planning is often framed around heat as an emergency, focusing on preventing loss of life and severe health impacts, yet a vulnerability perspective also draws attention to the chronic and persistent impacts of heat. Our research, based on interviews and desktop research in Melbourne, Australia, found tensions between addressing heat as an emergency and heat as a source of chronic stress, with emergency responses taking precedence over responses addressing the chronic dimensions of heat. Each approach results in different but nonetheless related programmatic priorities for reducing vulnerability. In complex institutional settings, improving relations between policy and programme managers, non-government organisations, and vulnerable people themselves would enable the multiple stresses associated with extreme heat to be more effectively addressed. Policy and institutional responses that better appreciate the interconnections between the emergency and chronic aspects of heat would likely reduce vulnerability and contribute to more just approaches to urban sustainability.  相似文献   
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