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701.
秦皇岛大气环境污染主要源于工业废气、港口煤尘、机动车尾气、施工及道路扬尘、锅炉烟尘和餐饮油烟等,是典型的复合型污染。针对秦皇岛大气污染现状,提出了改变以GDP为评价标准的经济增长模式,调整现有的产业结构,淘汰落后产能;调整能源结构,提高能源有效利用率;强化降尘控烟和脱硫脱硝;加强对交通、道路、施工等扬尘的综合管理;科学绿化;加强环保宣传和执法力度,提高公众环境意识等综合措施。 相似文献
702.
We examine how competition affects toxic industrial releases, using five years of data from thousands of facilities across hundreds of industries. Our main result indicates that competition reduces toxic releases at the facility level. On average, each percentage-point reduction in the Herfindahl Index (HHI) results in a nearly two-percent reduction in a facility׳s toxic releases. At the same time, we find no evidence that competition increases aggregate pollution. Further analysis sheds some light on the mechanisms through which firms reduce pollution releases due to increased competition. In particular, we find suggestive evidence that this relationship is due to both reduced output and increases in abatement. We find no evidence that our result is driven by: consumer aversion to pollution, regulations changing with competition, or technologies introduced by new firms. Taken together, our results indicate that competition may be good, at least for public health in areas near polluting facilities, and fail to provide support for the hypothesis that competition leads to more socially undesirable behavior. 相似文献
703.
We study the introduction of new technologies when their costs are subject to idiosyncratic uncertainty and can only be fully learned through individual experience. We set up a dynamic model of clean experience goods that replace old polluting consumption options and show how optimal regulation evolves over time. In our base setting where social and private learning incentives coincide, the optimal tax on the polluting consumption is increasing over time. We show, however, that if social and private learning incentives diverge because the private discount rate exceeds the social discount rate, it may be optimal to temporarily increase the tax rate beyond net marginal external damages to induce more learning before reducing the tax rate to the steady state level. Alternatively, one could complement the tax with subsidies for first-time users which can be phased out over time. Similar results apply if consumers have biased expectations. We therefore give a rationale for introductory subsidies on new, clean technologies and non-monotonic tax paths from a perspective of consumer learning. 相似文献
704.
Roberto Danovaro 《Chemistry and Ecology》2013,29(1):15-32
This overview summarises the present knowledge on major sources of pollution, which are of concern for the Mediterranean Sea. Eutrophication, red tides, organic loads, hydrocarbon spills, heavy metal contamination and their biological effects are described on the light of the ecological characteristics of the Mediterranean. In particular special attention is paid to the "new pollution" processes; i.e. , the introduction of novel substances with biological activity that might have synergetic effects with "classical pollutants". Different compartments and marine ecosystems are considered and compared. The degree of anthropogenic impact and its apparent trends are discussed. Possible monitoring plans and remedial actions for a sustainable management of coastal zones subjected to increasing pollution are also suggested. 相似文献
705.
As part of a pollution monitoring study, oysters (Crassostrea gasar) were sampled in June 1996, in order to determine the concentrations and distribution of chlorinated hydrocarbons in two stations (near Boulay Island and Riviera Golf) of the Ebrie Lagoon, in the Abidjan area. The chromatographic analysis of the oven dried samples revealed the presence of PCBs (2.13 to 86.22 ppb or ng/g dry weight), DDE (<0.48 to 169.55 ppb), DDD (<1.04 to 60.27 ppb), DDT (1.43 to 77.81 ppb, lindane (<0.22 to 91.64 ppb), aldrin (<0.30 to 154.1 ppb), endrin (<0.23 to 293.31 ppb) and dieldrin (<0.26 to 199.74 ppb). the results indicated high concentrations in oysters sampled near Boulay Island, due to industrial, agricultural and port activities going on in this area. Compared to DDD/ΣDDT and DDT/ΣDDT, the DDE/ΣDDT ratios were high indicating old DDT inputs. the ΣDDT/PCBs ratios were higher than 1 illustrated the predominance of organochlorine inputs from agriculture activities. the presence of lindane in both stations illustrated the problem of fishing with toxic products. Negative correlations found between dry tissue weight and organochlorine compounds concentrations showed that young oysters may concentrate more of these substances. More studies are needed in order to make any conclusions on their bioaccumulation trends. 相似文献
706.
本文分析了当前国内应急救援服装存在服装种类不统一、结构设计较欠缺、综合功能单一等一些问题,提出了坚持产品配套、注重材料选择、突出功能综合、重视人体功效的适合多种救援任务的救援服装设计思路。 相似文献
707.
黄山风景名胜区生态安全现状分析 总被引:2,自引:1,他引:1
黄山风景区是我国乃至世界上宝贵的资源,保持景区自然体系的生态安全是黄山风景区可持续利用和发展的关键.本文采用周广胜、张新时建立的自然植被第一性生产力模型对黄山风景区的生态完整性维护现状进行量化分析,并结合景区内敏感资源的生态需求满足程度和环境容量状况,对黄山景区的生态安全现状进行评价.结果表明,黄山风景名胜区自然系统处于高亚稳定平衡状态,具有较强的抵抗外界不良干扰的能力和破损生境的修复能力,但要注意规范和控制人类活动的扰动,保护珍稀动物,优化水资源的利用. 相似文献
708.
长管拖车作为专用气体储运装备实现国产化已有10余年时间,其关键部件——长管拖车气瓶(即大容积无缝钢瓶)由于充装介质多易燃、易爆、且具腐蚀性和毒性,具有较高的安全隐患和潜在危险,因此国家将其纳入特种设备进行全寿命安全监管。中国特种设备检测研究院作为长管拖车定期检验专业机构,累计检验长管拖车气瓶万余只,对其制造使用工况、典型失效模式和缺陷评定方法积累了大量数据。本文综述了我国长管拖车气瓶的制造使用现状、安全检验现状和发展趋势,为长管拖车在我国的安全使用及发展提供依据。 相似文献
709.
Carbon leakage is of interest in both academic and policy debates about the effectiveness of unilateral climate policy, especially in Europe, where the EU Emissions Trading System (EU ETS) affects many traded sectors. We review how the literature identifies leakage and the pollution haven effect. We then evaluate whether EU ETS emission costs caused carbon leakage in European manufacturing, using trade flows in embodied carbon and value from the Global Trade Analysis Project (GTAP). We find no evidence that the EU ETS caused carbon leakage. 相似文献
710.
In 2010 the Gulf Coast experienced the largest oil spill affecting U.S. waters in history. Evaporating crude oil and dispersant chemicals can cause major health problems. This paper examines the impact of the Deepwater Horizon oil spill on air quality and infant health outcomes. Using U.S. Environmental Protection Agency (EPA) AirData, vital statistics data from National Center for Health Statistics (NCHS), and a difference-in-difference methodology, we find that the oil spill of 2010 increased concentrations of PM2.5, NO2, SO2, and CO in affected coastal counties, increased incidence of low birth weight (<2500 g) and premature born infants (<37 weeks of gestation). Heterogeneity effects reveal more pronounced adverse infant health outcomes for black, Hispanic, less educated, unmarried, and younger mothers. Results are robust to a wide range of controls and robustness checks. 相似文献