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101.
This paper examines possible ozone-induced foliar injury to ponderosa pine areas in the Rincon Mountains of southern Arizona from 1972 to 1992. Spatiotemporal differences in a satellite-derived vegetation index (VI) are examined with respect to antecedent moisture conditions, temporal variations in ozone exposure levels, and measured foliar injury values from 1985. Seasonal ozone exposure levels (SUM60 and W126) increased from 1982 to 1998 and were significantly correlated (r = 0.49 and 0.53, α= 0.05) with annual population totals in the Tucson area. Extensive masking of satellite images from 1972, 1986, and 1992 resulted in two optimal change detection areas, with one site, TVWMica, exposed mostly to the Tucson air pollution plume, while the other site, EMica, was more protected from Tucson-derived pollution. An overall increase in VI from 1972 to 1992 at both sites appears to have been caused by an increase in moisture availability. Larger foliar injury values in 1985 were associated with a smaller increase in VI (i.e., a smaller increase in green leaf biomass) from 1972 to 1986. From 1972 to 1986 and from 1986 to 1992, VI values at TV/WMica increased at a slower rate compared to those at EMica. The reduced increase in “green-up” may have been caused partially by ozone-induced foliar injury and resulting decreases in green leaf biomass. However, these spatial differences in VI values may have also been caused by a number of other factors. Results nevertheless reveal the strong possibility of distinct, topographically based, spatial variations in ozone-induced foliar injury within the Rincons.  相似文献   
102.
The European Union Landfill Directive calls on member states to reduce the amount of biodegradable municipal solid waste disposed of to landfill. In addition, national waste strategies will require the constituent parts of the United Kingdom to achieve increased household waste recycling and recovery rates. Both these measures will require the development of the infrastructure to support national high-intensity recycling and composting schemes and the construction of at least 35 new municipal waste to energy incinerators. Before plans can be developed for meeting the targets several areas relating to municipal solid waste need to be clarified. Depending on the definition of municipal solid waste, its composition and likely future growth rates the number of incinerators required could be up to 170.  相似文献   
103.
介绍了英国负责海洋保护的主要管理机构,研究了英国海洋保护的相关法律与政策,分析了英国关于建立公海保护区的立场。从我国利益角度出发,对设立公海保护区所产生的利弊进行了分析。  相似文献   
104.
Lutz E. Helde 《Disasters》1987,11(3):205-213
In March/April 1985 a cholera epidemic of explosive speed affected a population of 45,000 newly arrived refugees in the town of Hargeysa in the North-West region of Somalia. Seven hundred and sixty one people were killed by the disease within ten days. Great efforts were made on regional, national and international levels in order to reduce mortality and to control the spread of the disease, and large amounts of relief supplies were immediately flown into the country from various aid organizations and governments. This paper describes the supplies management during the operation, with an emphasis on the mobilization of supplies from abroad and from the capital into the emergency area. Recommendations are offered for the organization of medical supplies during cholera outbreaks. The author worked during the epidemic as co-ordinating secretary for relief supplies in Mogadishu.  相似文献   
105.
污水处理厂运行对沈阳市地表水环境质量改善的探讨   总被引:1,自引:1,他引:0  
论述了沈阳市污水处理厂的建设及运行情况,在论述沈阳市污水处理厂运行状况与浑河水质变化的基础上,阐述了污水处理厂的建设与运行对水环境质量改善的作用。  相似文献   
106.
环境问题是全球性问题,应对环境问题的需要催生了联合国环境规划署。其是联合国系统内最早成立的专门处理环境问题的机构,且为在全球层面上处理环境问题作出了重要贡献。自1972年成立以来,以里约会议为分界点,联合国环境规划署的发展可分为两个阶段,其在这两个阶段的发展状况有所不同。UNEP成立以来为世界环境保护事业做了很多努力,取得了可喜的成绩,但是世界环境恶化的趋势并没有得到遏制,国际环境管理体制存在着诸多的问题,UNEP面临着巨大的挑战和新的机遇。  相似文献   
107.
本文通过对美国地下水中高氯酸盐的污染状况、污染来源及处理方法的研究,浅析了该国在该领域的技术状况和污染处理的运营模式。  相似文献   
108.
American Petroleum Institute (API) standards and recommended practices have identified inadvertent mixing of hot and cold liquids as a potential cause for equipment overpressure since 1955. The limited guidance has been informative but provides minimal if any details on conditions that could cause an overpressure and its potential severity. Therefore, the user must interpret how and when to prevent and/or mitigate the scenario. This guidance has changed little over the years. In June 2020, API published the 7th Edition of API Standard 521 which now provides specific guidance as to conditions whereby pressure relief devices can be considered for protection and conditions where prevention remains as the only recourse. This paper discusses the basis for the revised guidance in API Standard 521 and includes supplemental guidance.  相似文献   
109.
This study analyzes Total Factor Productivity (TFP), which includes all categories of productivity. Our measure investigates productivity in the context of the provision and dissemination of environmental information policies. We investigated data on the emission of toxic chemical substances for the U.S. and Japanese manufacturing firms, including 386 firms for the period 1999-2007 and 466 firms for the period 2001-2008. The results show that productivity improved in all nine industrial sectors and that pollution levels were high in the U.S. and Japan from 2001 to 2007. In particular, the electronics industry improved rapidly after 2002 in both countries, which may be attributed to the enforcement of RoHS and the REACH directive in Europe. As a result of these stringent policies on toxic chemical emissions, the U.S. and Japanese firms, many of which export to the European market, have strong incentives to reduce their toxic chemical emissions.  相似文献   
110.
美国作为全球温室气体排放大国之一,在国际气候谈判中的立场至关重要。本文从州政府和地方政府角度总结了美国已采取的减排努力措施,分析了德班会议前后其应对气候变化动向,探讨了对我国采取温室气体减排行动和措施的借鉴意义和启示。美国由于受到持续低迷的经济环境,缓慢的国际气候谈判进程,以及2012年总统大选的影响,国内温室气体减排行动和措施实质进展缓慢,我国应总结和借鉴美国已采取减排行动措施的经验教训,从加快建立健全国内气候立法体系,推动国内碳市场建立出发,积极应对国内外气候变化制度中存在的不确定性,不断提高我国在国际气候谈判中的地位。  相似文献   
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