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961.
• Dual-reaction-center (DRC) system breaks through bottleneck of Fenton reaction. • Utilization of intrinsic electrons of pollutants is realized in DRC system. • DRC catalytic process well continues Fenton’s story. Triggered by global water quality safety issues, the research on wastewater treatment and water purification technology has been greatly developed in recent years. The Fenton technology is particularly powerful due to the rapid attack on pollutants by the generated hydroxyl radicals (•OH). However, both heterogeneous and homogeneous Fenton/Fenton-like technologies follow the classical reaction mechanism, which depends on the oxidation and reduction of the transition metal ions at single sites. So even after a century of development, this reaction still suffers from its inherent bottlenecks in practical application. In recent years, our group has been focusing on studying a novel heterogeneous Fenton catalytic process, and we developed the dual-reaction-center (DRC) system for the first time. In the DRC system, H2O2 and O2 can be efficiently reduced to reactive oxygen species (ROS) in electron-rich centers, while pollutants are captured and oxidized by the electron-deficient centers. The obtained electrons from pollutants are diverted to the electron-rich centers through bonding bridges. This process breaks through the classic Fenton mechanism, and improves the performance and efficiency of pollutant removal in a wide pH range. Here, we provide a brief overview of Fenton’s story and focus on combing the discovery and development of the DRC technology and mechanism in recent years. The construction of the DRC and its performance in the pollutant degradation and interfacial reaction process are described in detail. We look forward to bringing a new perspective to continue Fenton’s story through research and development of DRC technology.  相似文献   
962.
Environmental Science and Pollution Research - Cobalt exposure has adverse health effects on the cardiovascular system in occupational and laboratory studies, but these effects have not been...  相似文献   
963.
薛航  韩路 《环境与发展》2020,(4):221-222
随着我国建筑建设的城镇化、现代化进程加快,为提升人民的生活质量带来了保障,由于建筑规模以及项目的增加,加剧了环境问题。在强调低碳经济的现代化社会,应该加强对建筑项目竣工验收工作的环保监测,针对竣工验收不环保的问题采取对策,促进建筑施工的绿色化发展。基于此,本文将针对当前建筑项目环保验收存在的问题展开探讨,并提出相应对策。  相似文献   
964.
China’s land institution can be defined broadly or narrowly. By examining the broad definition of the land institution, we found that there were prerequisite, complementary, and substitutional relationships among the various systems. These relationships were verified through discussion of the structural evolution of each system. Based on these relationships, three methods for quantification were used to measure the regulation intensity and intra-provincial differences in each system among 31 provinces, municipalities, and autonomous regions in China in 2014. The statistics analysis shows that provinces used to pursue outstanding performances in land institution but few provinces could outperform the other provinces in all types of systems. The statistics results also indicate that the provinces which executed land institution earlier often hold significant advantages in institutional innovations but it is still not clear whether they can maintain the advantages. This study recommends that the Chinese government should improve the overall framework of regional land institution based on land systems’ relationships and evolutionary patterns. Furthermore, the government should optimize the spatial distribution of regional land institution based on the intra-provincial differences in land-regulation intensity.  相似文献   
965.
为防止木材加工中木质粉尘燃爆事故的发生,以纤维板生产中常见的原材料速生杨木粉尘作为研究对象,在分析粉尘粒径分布、元素分析、工业分析及形貌特征的基础上,采用1.2 L哈特曼管对3种不同粒径(0~50,>50~96,>96~180 μm)速生杨木粉尘进行最小点火能实验,探究点火延迟时间、喷粉压力、质量浓度和粒径分布对速生杨木粉尘最小点火能的影响及变化规律。研究结果表明:在质量浓度为500 g/m3时,分别增加点火延迟时间和喷粉压力,最小点火能都先减小后增大;最佳点火延迟时间和最佳喷粉压力分别为120 ms和120 kPa;粒径对最佳点火延迟时间和最佳喷粉压力无显著影响。在点火延迟和喷粉压力分别为120 ms和120 kPa条件下,最小点火能随质量浓度的增加先减小后增大。粉尘粒径与最小点火能呈正相关性,3种样品的最小点火能分别为1~3,1~3和7~13 mJ,对应的敏感质量浓度分别为500 ,750和1 250 g/m3,属于特别着火敏感性粉尘。  相似文献   
966.
Environmental Science and Pollution Research - Cyanobacterial blooms caused by Microcystis have become a menace to public health and water quality in the global freshwater ecosystem. Alkaline...  相似文献   
967.
Some conservation prioritization methods are based on the assumption that conservation needs overwhelm current resources and not all species can be conserved; therefore, a conservation triage scheme (i.e., when the system is overwhelmed, species should be divided into three groups based on likelihood of survival, and efforts should be focused on those species in the group with the best survival prospects and reduced or denied to those in the group with no survival prospects and to those in the group not needing special efforts for their conservation) is necessary to guide resource allocation. We argue that this decision-making strategy is not appropriate because resources are not as limited as often assumed, and it is not evident that there are species that cannot be conserved. Small population size alone, for example, does not doom a species to extinction; plants, reptiles, birds, and mammals offer examples. Although resources dedicated to conserving all threatened species are insufficient at present, the world's economic resources are vast, and greater resources could be dedicated toward species conservation. The political framework for species conservation has improved, with initiatives such as the UN Sustainable Development Goals and other international agreements, funding mechanisms such as The Global Environment Facility, and the rise of many nongovernmental organizations with nimble, rapid-response small grants programs. For a prioritization system to allow no extinctions, zero extinctions must be an explicit goal of the system. Extinction is not inevitable, and should not be acceptable. A goal of no human-induced extinctions is imperative given the irreversibility of species loss.  相似文献   
968.
Environmental Science and Pollution Research - The occurrence, distribution, sources, and ecological risks of organochlorine pesticides in Dongting Lake of China were investigated. The average...  相似文献   
969.

One of the key issues facing the government in achieving carbon neutrality is what methods can be used to effectively reduce carbon emissions. Taking manufacturing enterprises as an example, this paper studies the carbon emission reduction effects of green technology innovation subsidy (GIS), carbon tax (CT), and carbon emission trading (CET). Under the background of social welfare and carbon emission reduction efficiency, we get the results of optimal carbon emission reduction measures in different environments. The results are as follows: (1) In the initial and mature stage of green technology innovation, GIS is the best choice to improve the degree of green manufacturing and maximize social welfare. CT and CET are the best choice to obtain the highest SE (carbon emission reduction efficiency). (2) In the transitional stage, CET and CT can promote the maturity of green technology. However, with the maturity of green technology, the promotion of green technology has weakened. CT is the best choice to achieve the highest SE. (3) When the carbon tax or carbon trading price is at a high or low level, raising the tax rate or carbon trading price can increase the income of enterprises. Therefore, the government should take measures according to the objectives of different stages. When the goal is to maximize social benefits, GIS is the best choice in the initial stage and transition stage, and CET or CT is the best choice in the transition stage. In the initial stage and fertilization stage, when the highest SE, CT, or CET is the best choice, while in the transition stage, CT is the best choice.

  相似文献   
970.
小型镁砂竖窑是辽南蛀区污染大气环境的主要污染源之一。文中通过对海城市镁砂窑污染现状的调查,介绍了海城市镁砂窑企业概况及自然条件,提出了环保治理的难点问题以及粉尘治理的可行性方案,和防治对策,并且为环保工作者提供了大量的基础依据。  相似文献   
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