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991.
本文以秦皇岛市为例,探讨了实施可持续发展的基本条件,并从生存与发展能力、生态建设与环境治理能力和社会保障与科技发展能力等三个方面评估了秦皇岛市的可持续发展能力。这种评估方法简便、数据易得、其结果具有很强的可比性和说服力,其评估结果可为城市制定可持续发展战略和实施环境与发展综合决策提供科学依据。  相似文献   
992.
Trichodiene, a volatile sesquiterpene which is structurally related to trichothecene mycotoxins, has been identified in the headspace of growing Stachybotrys chartarum by GC/MS. It is possible that volatile sesquiterpene patterns can be used to characterize S. chartarum and related mold isolates as trichothecene producers, thus providing clear criteria for decisions concerning the occupancy and renovation of contaminated buildings.  相似文献   
993.
Efficient environmental protection requires global, as well as regional ecological strategies. During the last decade numerous attempts at regional and global environmental protection have been made. But industrial environmental protection is still, above all, a national matter. National emission limit values and international technological standards still neglect to a large extent the regional aspects of pollution prevention. Recent normative texts (international standards, European directives) can be seen as the first step to filling this gap. They represent different evolutionary stages on the way from merely technocentric to regionally integrated environmental protection. We investigate the potential of some of these normative texts to operationalise regional environmental strategies. For this purpose we will provide a framework for evaluation centred on the following questions: ? Is the installation/project/organisation perceived as part of its specific environment? ? Can local immission standards be developed on the basis of a functional classification of ecosystems? ? Are methods of integrated ecological evaluation supported? The framework will be applied to examine the European directives on Environmental Impact Assessment and Integrated Pollution Prevention and Control and two ISO (International Standardisation Organisation) standards on Environmental Management Systems (ISO 14001 and 14004) with regard to basic requirements for operationalising integrated regional environmental protection.  相似文献   
994.
The objective of this article is to illustrate the use of a framework to design a set of tools to assess progress towards improved well-being in a mining region. The framework uses an ecosystem approach to assess human well-being and is sensitive to the needs, concerns, and interests of at least the major stakeholders: government, company and community. The framework seeks to be useful to stakeholders and to be of policy relevance. The article presents the proposed framework with illustrations from a case study in Goa, India. Mining in Goa has had both positive and negative impacts on the well-being of local people. These impacts vary depending on the age of mining. In areas where mining is well established and active, the economic impacts are more positive. The social and environmental impacts are more negative in the regions where mining is new or is closing down. These characteristics generate their own set of issues of concern to stakeholders. Based on these issues, three types of tools to assess current well-being and progress towards improved well-being are suggested: (i) Indicators based on identified issues using the Pressure-State-Response (PSR) framework; (ii) A quality of life instrument, which can be developed either as an aggregate measure of well-being or in a more limited way to capture the satisfaction of the community with their living conditions; (iii) A regional income accounting framework to assess whether the mining region is able to continue functioning into the indefinite future without being forced into a decline through the degradation of its key natural, social, and human assets and resources. The article suggests that if these tools are used regularly, an information system will emerge that will, over time, provide markers of what mining is doing to the region and to the local communities.  相似文献   
995.
在黄河三角洲耿井水库周围布设不同边界条件的地下水监测井和土壤监测点,进行为期1年的定点采样和化验,对地下水矿化度和土壤含盐量的监测分析表明,减轻平原水库对环境不利影响的关键是修建防渗与截渗辅助工程,以避免周边土地的盐渍化.  相似文献   
996.
通过对南水北调东线工程调蓄湖泊湿地水资源的评价,提出防御调蓄湖泊湿地水生态恶化的环境保护措施,以减轻或消除工程可能带来的不利影响,使湖泊湿地水生态系统朝着有利于人类的方向发展.   相似文献   
997.
运用ISC3模型模拟电厂脱硫后的大气环境影响   总被引:12,自引:0,他引:12       下载免费PDF全文
运用美国ISC3模型对北京京丰热电有限责任公司现状及采用电子束氨法烟气脱硫后的SO2和NOx排放对环境空气质量的影响进行了模拟.结果表明:该公司现状SO2排放的主要受影响地区在丰台西部和房山北部,石景山和门头沟南部局部地区也受到一定影响,对老城区的影响很小,SO2年均质量浓度最大值为6.10 μg/m\+3,占二级标准的10.2%,NOx的影响区域与SO2相似,年均质量浓度最大值为4.27 μg/m\+3,占二级标准的5.3%;采用电子束氨法脱硫技术后,燃煤含硫量分别为0.79%,2%和0.5%的情况下,SO2年均质量浓度最大值分别降到0.86,2.17,0.55 μg/m\+3,比现状降低了86%,64%,91%,NOx年均质量浓度最大值降到了3.42 μg/m3,比现状降低了20%.   相似文献   
998.
Abstract:  In recent centuries bird species have been deteriorating in status and becoming extinct at a rate that may be 2–3 orders of magnitude higher than in prehuman times. We examined extinction rates of bird species designated critically endangered in 1994 and the rate at which species have moved through the IUCN (World Conservation Union) Red List categories of extinction risk globally for the period 1988–2004 and regionally in Australia from 1750 to 2000. For Australia we drew on historical accounts of the extent and condition of species habitats, spread of invasive species, and changes in sighting frequencies. These data sets permitted comparison of observed rates of movement through the IUCN Red List categories with novel predictions based on the IUCN Red List criterion E, which relates to explicit extinction probabilities determined, for example, by population viability analysis. The comparison also tested whether species listed on the basis of other criteria face a similar probability of moving to a higher threat category as those listed under criterion E. For the rate at which species moved from vulnerable to endangered, there was a good match between observations and predictions, both worldwide and in Australia. Nevertheless, species have become extinct at a rate that, although historically high, is 2 (Australia) to 10 (globally) times lower than predicted. Although the extinction probability associated with the critically endangered category may be too high, the shortfall in realized extinctions can also be attributed to the beneficial impact of conservation intervention. These efforts may have reduced the number of global extinctions from 19 to 3 and substantially slowed the extinction trajectory of 33 additional critically endangered species. Our results suggest that current conservation action benefits species on the brink of extinction, but is less targeted at or has less effect on moderately threatened species.  相似文献   
999.
Abstract:  Suburban, exurban, and rural development in the United States consumes nearly 1 million hectares of land per year and is a leading threat to biodiversity. In response to this threat, conservation development has been advanced as a way to combine land development and land conservation while providing functional protection for natural resources. Yet, although conservation development techniques have been in use for decades, there have been few critical evaluations of their conservation effectiveness. We addressed this deficiency by assessing the conservation outcomes of one type of conservation development project: conservation and limited development projects (CLDPs). Conducted by land trusts, landowners, and developers, CLDPs use revenue from limited development to finance the protection of land and natural resources. We compared a sample of 10 CLDPs from the eastern United States with their respective baseline scenarios (conventional development) and with a sample of conservation subdivisions—a different conservation development technique characterized by higher-density development. To measure conservation success, we created an evaluation method containing eight indicators that quantify project impacts to terrestrial and aquatic ecosystems at the site and in the surrounding landscape. The CLDPs protected and managed threatened natural resources including rare species and ecological communities. In terms of conservation benefits, the CLDPs significantly outperformed their respective baseline scenarios and the conservation subdivisions. These results imply that CLDPs can offer a low-impact alternative to conventional development and a low-cost method for protecting land when conventional conservation techniques are too expensive. In addition, our evaluation method demonstrates how planners and developers can incorporate appropriate ecological considerations when designing, reviewing, and evaluating conservation development projects.  相似文献   
1000.
尤飞  石王莹  胡源 《火灾科学》2005,14(4):258-266
本文运用一步熔融共混法制备了含有十溴联苯醚(DBDPO)或十溴二苯乙烷(DBDPE)和C16改性蒙脱土(MMT)的高抗冲聚苯乙烯(HIPS)复合材料,并采用X射线衍射(XRD)、透射电镜(TEM)、UL 94垂直燃烧和锥型量热等试验手段对其燃烧性能和相态进行了表征.结果标明,DBDPO/E存在时仍可获得具有插层结构的HIPS纳米复合材料.由于十溴和蒙脱土两种体系间的良好协同效应,这些材料的阻燃性提高、燃烧后的热释放速率下降.文中对其潜在机理进行了探讨.这种协同效应可用于指导发展环保性和阻燃性兼顾的HIPS纳米复合材料.  相似文献   
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