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991.
基于STIRPAT模型的重庆市能源消费碳排放影响因素研究   总被引:6,自引:2,他引:4  
黄蕊  王铮 《环境科学学报》2013,33(2):602-608
定量分析人类活动对环境的影响,对减少碳排放和建设环境友好型社会具有重要的指导意义.因此,本文采用重庆市1980-2010年能源消费碳排放时间序列数据,基于STIRPAT模型,通过岭回归拟合得到能源消费碳排放与人口数量、人均GDP及其二次项、能源强度、第三产业比重、城镇化水平的多元线性模型.结果表明,人口数量、人均GDP、能源强度、城市化水平每增加1%,将引起重庆市能源消费碳排放相应增加0.963%、(0.398 +0.463lnA)%、0.059%、0.266%,其中,A为人均GDP.可以看出,人口数量对重庆市能源消费碳排放量影响最大.第三产业比重每增加1%,能源消费碳排放将会减少0.093%.  相似文献   
992.
建设用地变化的碳排放效应是现阶段土地利用变化研究热点之一.因此,本文运用安徽省统计年鉴数据,采用建设用地动态度模型及IPCC碳排放计算方法,对安徽省1997-2011年建设用地与碳排放动态变化特征进行了分析.同时,基于STIRPAT模型,采用偏最小二乘回归方法,揭示了建设用地对碳排放的边际效应,并运用SPSS软件对未来碳排放进行了预测.结果表明:研究时序内,建设用地与碳排放均呈增长态势,建设用地年均扩展速率为16.91%,碳排放年均增长6.61%,建设用地与碳排放正向效应显著;建设用地对碳排放的边际弹性系数为0.1194;惯性情景模式下,2015年、2020年安徽省建设用地扩展导致的碳排放将分别增至14472.42万t、19930.37万t;通过政策规制控制建设用地扩展趋势有利于抑制或减缓碳排放.本研究对了解安徽省碳排放变化趋势和指导土地利用规划有重要的现实意义,也可为省域尺度的建设用地碳排放效应研究提供范式借鉴.  相似文献   
993.
木家具关键挥发性有机化合物散发传质特性   总被引:1,自引:0,他引:1  
木家具中挥发性有机化合物(Volatile Organic Compounds,VOCs)的散发是一个污染环境的复杂传质过程.为把握污染物散发全周期特性,首先建立了一套描述散发行为的显性完全解析模型,适用于模拟对人体最不利的无换气情况.然后基于对模型的分析开发了一种简便快捷的实验方法,能够利用木家具在密闭舱中散发的逐时浓度求取目标VOCs的3个重要传质参数:可散发浓度C0、扩散系数D和分配系数K.实验部分测算了从10个厂家依多种原材料定制的5类20件常见家具,参考出现频率、健康影响、可散发量确定了19类关键污染物,发现总体C0、D、K服从正态分布.此外,结合常见散发参数范围下的数值实验和参数回归分析,提出一组反映散发机理、预测类比不同时空尺度下散发数据的准则关联式,并分析得出空气交换率和承载率对散发影响较大、空气流速对散发影响较小.  相似文献   
994.
在建设项目环境影响评价中,非甲烷总烃、VOCs、TVOC这三个污染因子经常混淆使用。本文从非甲烷总烃、VOCs、TVOC三个污染因子的定义、监测方法等方面研究了三个因子的差异,并根据其差异,在环评工作中加以运用;提出多种有机污染物评价因子的识别、筛选原则,讨论了相应评价标准的选取方法和环境现状监测中应注意的事项。  相似文献   
995.
人文发展的基本需要途径从满足基本需要和限制奢侈浪费性排放出发,充分利用技术在实现低碳发展方面的潜力,保障气候目标的实现和代内与代际公平。本文在讨论发展所面临的消除贫困、城市化和工业化挑战的基础上,区分了生存水平和体面生活水平的基本需要,依据国际数据和科学研究成果,对基本需要进行了量化界定。并在此基础上,对满足13亿中国人体面生活水平的基本需要的能源和排放含义,进行了案例研究。最后探讨了基本需要途径在国际气候制度设计中的应用和前景。  相似文献   
996.
Toxic releases from medical waste incineration comprising organic emissions such as polychlorinated dibenzo-dioxin/furan (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs), inorganic emissions and ashes containing toxic metals have been reviewed. Attempts made by various investigators to reduce/eliminate emissions have also been included. Legislations concerning emission standards for medical waste incinerators have been discussed.  相似文献   
997.
富勒烯的吸附性及其在大气挥发性有机物分析中的应用   总被引:2,自引:0,他引:2  
富勒烯不含官能团,对挥发性有机物具有化学惰性,能在效地吸附VOCs,吸附VOCs气体后存放稳定,组分流失少,9种mg.l^-1级VOCs在富勒烯吸附管上的吸附突破体积为14.8-48.0L.g^-1,吸附-热脱附回收率在86.5-123%之间。  相似文献   
998.
The reduction of SO2 by ammonia gas additionduring staged combustion of bituminous coal has beenstudied in a 2 m high fluidized bed combustor of 30 cmstatic bed height and a freeboard height of 100 cm.The coal was introduced to the combustor at 42 cmabove the distributor and the ammonia gas was injectedat 52 cm above the distributor by an uncooledstainless steel injector. Experiments were carriedout to investigate effects of ammonia gas injection onSO2 emissions of (i) air staged levels, (ii) excess air levels, (iii) primary air factor, PAF(ratio of primary to stoichiometric air), (iv) NH3:SO2 molar ratio, and (v) fluidizingvelocity. Experiments were carried out under a newtechnique of air staging called Pseudo-stagedCombustion, maintaining the excess air level andfluidizing velocity between 17 and 70% and between0.7 and 2.0 m sec-1, respectively. A maximum reduction of92% was obtained at 37% excess air, at NH3:SO2 molar ratio of 5.5. The effective NH3:SO2 molar ratio was found to be between 3.0 and5.5, which is true for all staging and excess air levels.A greater removal of SO2 with NH3 injectionduring staged combustion is probably due to this newstaging technique. The Pseudo-staging reducestemperature through the freeboard and flue for theoccurance of as NH3 + SO2 reactions. Thesereactions are reported to be low temperaturereactions. The NH3 carry over was less than 83 ppm for all operating conditions. The present studydemonstrates that staged combustion coupled withammonia injection can reduce SO2 emissions.  相似文献   
999.
This paper examines the flow of cadmium through the global economy, with the aim of quantifying emissions of cadmium into the environment as a result of anthropogenic activities. First, a materials balance methodology is presented as the most appropriate means of assessing cadmium emissions from a wide range of anthropogenic sources. This is then applied to the best available data, from a variety of sources, to arrive at estimated flows of cadmium. Results are presented for 10 geo-political world regions and for a range of economic activities including non-ferrous metals production, iron and steel production, combustion of fossil fuels, fertilizer manufacture and use, cement production and the manufacture, use and disposal of cadmium containing products. Initially, this analysis partitions the total flow of cadmium into three major categories: atmospheric emissions, water-borne effluents and solid or bulked waste arisings. the paper then suggests a probable further partition of the initial emissions into different environmental media.  相似文献   
1000.
A Chronology of Nitrogen Deposition in the UK Between 1900 and 2000   总被引:2,自引:0,他引:2  
Measurements of the concentrations of nitrogen compounds in air and precipitation in the UK have been made since the mid-19th century, but no networks operating to common protocols and having traceable analytical procedures were established until the 1950s. From 1986 onwards, a high-quality network of sampling stations for precipitation chemistry was established across the UK. In the following decade, monitoring networks provided measurement of NO2, NH3, HNO3 and a satisfactory understanding of the dry deposition process for these gases allowed dry deposition to be quantified. Maps of N deposition for oxidized and reduced compounds at a spatial scale of 5 km × 5 km are available from 1986 to 2000. Between 1950 and 1985, the more limited measurements, beginning with those of the European Air Chemistry Network (EACN) provide a reasonable basis to estimate wet deposition of NO 3 –N and NH 4 + –N. For the first half of the century, estimates of deposition were scaled with emissions assuming a constant relationship between emission and deposition for each of the components of the wet and dry deposition budget at the country scale. Emissions of oxidized N, which dominated total nitrogen emissions throughout the century, increased from 312 kt N annually in 1900 to a peak of 787 kt for the decade 1980–1990 and then declined to 460 kt in 2000. Emissions of reduced N, largely from coal combustion were about 168 kt N in 1900, increasing to a peak of 263 kt N in 2000 and by now dominated by agricultural sources. Reduced N dominated the deposition budget at the country scale, increasing from 163 kt N in 1900 to 211 kt N in 2000, while deposition of oxidized N was 66 kt N in 1900 and 191 kt N in 2000. Over the century, 68 Mt (Tg) of fixed N was emitted within the UK, 78% as NO x , while 29 Mt of nitrogen was deposited (43% of emissions), equivalent to 1.2 t N ha–1, on average, with 60% in the reduced form. Deposition to semi-natural ecosystems is approximately 15 Tg N, equivalent to between 1 and 5 t N ha–1, over the century and appears to be accumulating in soil. The N deposition over the century is similar in magnitude to the total soil N inventory in surface horizons.  相似文献   
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