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31.
Environmental Economics and Policy Studies - This paper dissects the effects of environmental regulation on the productivity of pollution-intensive industries and by doing so offers a new...  相似文献   
32.
Environmental Science and Pollution Research - Production of the greenhouse gas nitrous oxide (N2O) from the completely autotrophic nitrogen removal over nitrite (CANON) process is of growing...  相似文献   
33.
Environmental Science and Pollution Research - In the context of global warming and environmental deterioration, the environment impact assessment is a crucial institutional guaranty to assure less...  相似文献   
34.

As an important renewable energy source, wind power plays a key role in mitigating climate change and has become one of the fastest growing clean energies globally. In China, wind energy development has been a vital component of national energy transformation strategy. Over the years, the Chinese government has introduced a series of policies to promote the development of wind power and also to regulate this emerging industry. Base on examining all the key policy documents on wind power issued by the Chinese government over the last 30 years, we find that China has built up a comprehensive policy system, and summarized the current framework of Chinese wind power policy systematically. Then, we analyze the policy objectives, policy tools, major measures, their results in each development stage, and the characteristics and trends of China’s wind power policies. Finally, we discuss the limitations of the current policy and put forward corresponding suggestions.

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35.
采用膜过滤-气相色谱法测定涂料中的苯系物、环己酮和甲苯二异氰酸酯(TD I)。用7种规格的石英毛细管色谱柱对混合标准溶液和涂料试样进行了分析实验,实验结果表明,不同属性的涂料试样添加固定量的正十四烷作内标物,经膜过滤净化后,苯系物、环己酮和TD I可采用DB-1-3或DB-1-2色谱柱同时分离并测定。测试数据经多级校准曲线处理后涂料试样中苯系物、环己酮和TD I的加标回收率为98.6%~101.8%,各组分分析结果的变异系数均小于2.0%,检出限均小于1.50×10^-5g。  相似文献   
36.
为了研究饱和砂土的液化机理,通过等体积加载的方式建立了循环荷载下饱和砂土动力响应的颗粒流计算模型,研究了饱和砂土在不同围压和加载幅值下的动力响应,探讨了颗粒间力链的发展特性,并从Shannon 熵、Boltzmann 熵以及Clausius 熵的基本关系入手,建立基于粒间接触力链的饱和砂土颗粒熵计算方法,分析了颗粒熵发展特性。结果表明:饱和砂土初始总力链主要受围压的影响,围压越大,初始总力链越多;循环荷载下饱和砂土颗粒间力链总数逐渐降低,且强力链持续向中、弱力链转换;循环荷载下饱和砂土颗粒熵表现出先升高后降低的二阶段特性,围压和加载幅值对颗粒熵峰值无明显影响,各工况的颗粒熵峰值均为0.92;定义颗粒熵峰值为相变颗粒熵,相变颗粒熵时的饱和砂土表现出固液临界态的力学特征,指示了饱和砂土由固态向往返液化状态转变的临界点。  相似文献   
37.

Wastewater treatment plants (WWTPs) have been recognized as important sources for anthropogenic greenhouse gas (GHG) emission. The objective of the study was to thoroughly investigate a typical industrial WWTP in southern Taiwan in winter and summer which possesses the emission factors close to those reported values, with the analyses of emission factors, mass fluxes, fugacity, lab-scale in situ experiments, and impact assessment. The activated sludge was the important source in winter and summer, and nitrous oxide (N2O) was the main contributor (e.g., 57 to 91 % of total GHG emission in a unit of kg carbon dioxide-equivalent/kg chemical oxygen demand). Albeit important for the GHGs in the atmosphere, the fractional contribution of the GHG emission to the carbon or nitrogen removal in wastewater treatment was negligible (e.g., less than 1.5 %). In comparison with the sludge concentration or retention time, adjusting the aeration rate was more effective to diminish the GHG emission in the activated sludge without significantly affecting the treated water quality. When the aeration rate in the activated sludge simulation was reduced by 75 %, the mass flux of N2O could be diminished by up to 53 % (from 9.6 to 4.5 mg/m2-day). The total emission in the WWTP (including carbon dioxide, methane, and N2O) would decrease by 46 % (from 0.67 to 0.36 kg CO2-equiv/kg COD). However, the more important benefit of changing the aeration rate was lowering the energy consumption in operation of the WWTP, as the fractional contribution of pumping to the total emission from the WWTP ranged from 46 to 93 % within the range of the aeration rate tested. Under the circumstance in which reducing the burden of climate change is a global campaign, the findings provide insight regarding the GHG emission from treatment of industrial wastewater and the associated impact on the treatment performance and possible mitigation strategies by operational modifications.

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38.
The only joint effort area of provincial and municipal governments resides in Guangdong Province and Shenzhen City in China’s carbon emission trading system (ETS) pilots, which characterize the national carbon ETS plots. The present study on the operating experience from this area has important reference value for the national carbon ETS. Analysis and comparison of the key elements show many differences in coverage, total allowance, allowance allocation, and MRV mechanism between Guangdong and Shenzhen carbon ETS. The present study provides the following explanation: (1) the design characteristics of carbon ETS (e.g. coverage, total quotas, the allocation, and MRV mechanism) depend on the local geographical conditions and policy goals. The differences of economic structure in Guangdong Province and Shenzhen City result in different coverage, which then result in differences in other management elements. (2) The operating state of the carbon market is affected by overall design of carbon ETS: in the case of tighter total allowance, lower proportion of China Certified Emission Reductions, and harsher punishment, the carbon market is relatively active, which intends to produce carbon financial market. Based on deep analysis of operation characteristics of carbon ETS in Guangdong and Shenzhen, the present study suggests that (1) the allowance should be allocated freely at the beginning stage and then gradually transited to the voluntary paid auction; (2) the allowances assigned to companies shall be linked up with their energy-saving objectives; (3) the output fluctuations and economic influence on the allowance allocation should be properly handled to maintain the fairness and consistence of allowance allocation standards; (4) stable public expectation is one of the key elements to maintain the regular operation of carbon ETS; (5) constrained carbon emission behavior outside ETS can contribute to social justice; and (6) the improvement of professional skills of relevant personnel in the enterprise and independent third party can enhance carbon emissions data reliability.  相似文献   
39.
中国水产养殖规划现状分析与对策   总被引:3,自引:0,他引:3  
水产养殖规划可以降低水产养殖和水环境之间的不确定性、减少水产养殖活动的外部不经济性、提高水资源的利用效率,对中国水产养殖的可持续发展有重要作用.对已实施的水产养殖规划的现状分析结果表明,存在着水产养殖规划基础与水产养殖规划实施间的不协凋性、环境影响评价环节的缺失和水产养殖规划的实施效果蔗等主要现象.其根本原因是现有水产养殖相关制度的配置不完善.应从环境影响评价与水产养殖规划的集成关系入手,通过完善水产养殖容量的估算、水产养殖的技术与经济评估指标、制度和相关利益者分析与评估的方法和指标,建立水产养殖规划的技术体系.引入第三方评审制度以监督规划环境影响评价的质量.  相似文献   
40.
通过恒温振荡平衡法研究了Pb~(2+)在针铁矿上的等温吸附和吸附动力学特征,探讨了吸附的影响因素.结果表明:(1)随Pb~(2+)平衡浓度和pH的增大,针铁矿对Pb~(2+)的吸附量逐渐增大.(2)针铁矿对Pb~(2+)的等温吸附可用Freundlich和Langmuir方程较好地拟合.(3)在相同温度和pH下,随离子强度的提高,针铁矿对Pb~(2+)的吸附量增大.(4)在相同离子强度和pH下,针铁矿对Pb~(2+)的吸附量总体随温度升高而增大.针铁矿对Pb~(2+)的吸附是自发进行的吸热反应.(5)针铁矿吸附Pb~(2+)的过程可分为初始的快吸附和随后的慢吸附2个阶段.pH影响吸附反应快慢,随pH增大吸附速率增大;随着pH的增大,达到平衡吸附的时间缩短.吸附动力学方程用Elovich方程拟合最佳.  相似文献   
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