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851.
大气和废气中邻苯二甲酸酯的监测方法   总被引:3,自引:0,他引:3  
本文通过气相色谱法建立了大气中邻苯二甲酸酯的监测方法。对大气和废气中的邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二辛酯(DOP)进行测定,从样品的采集到色谱条件的选择,进行了一系列实验方法探讨。该方法检出限大大低于DBP、DOP的环境目标值,结果令人满意。  相似文献   
852.
大气连续采样质量保证初探   总被引:1,自引:0,他引:1  
阐述了建立大气连续采样质量保证考核办法的必要性,介绍了大气连续采样质量保证考核办法的建立依据、考核内容、组织实施、应用举例及取得的成效,对如何做好大气连续采样的质量保证工作进行了初步探讨  相似文献   
853.
How effective was the Kyoto protocol? International Environmental Agreements (IEA) have been on the rise over the past four decades; however, thus far their effectiveness is controversial. In view of the conflicting results found in the related literature, this paper addresses its effectiveness by utilizing for the first time the generalized synthetic control method (GSCM) to compare the emissions of the industrialized countries with a “No- Kyoto” counterfactual scenario that represents the expected emissions in the absence of the protocol. This method facilitates a robust comparison between treated and control countries as done by Almer and Winkler (2017) and account for the multiple treated units as done by Grunewald and Martinez-Zarzoso (2016), so as to capture the collective nature of the protocol. Results show that the protocol was successful in reducing the emissions of the ratifying countries approximately by 7% below the emissions expected under a “No-Kyoto” scenario, confirming the importance of accounting for the collective nature of the agreement.  相似文献   
854.
The topic of air pollution has drawn considerable attention globally. In this paper, we examine the immediate effect of air pollution on a substantial decision, that is, a housing purchase. By linking housing purchasing behavior with the air quality in Beijing, we document market participants' behaviors unexplained by rational economic theories. Our main result suggests that the transaction prices on a severely polluted day are 0.65% higher than those of the days without pollution, other things being equal. This translates into approximately 3.51 million yuan daily increase based on the average transaction volume and price on a typical day in Beijing. The heterogeneity analysis further suggests that this effect is mostly driven by non-local and low income buyers. After ruling out rational explanations, we demonstrate that our empirical results are consistent with salience theory under weak assumptions.  相似文献   
855.
The Kathmandu Valley in Nepal has experienced a very rapid increase in population resulting in considerable land use/land cover change and also a series of environmental problems. One of the results of the population increase is an expansion of brick manufacturing within the Valley because most structures are brick. The brick kilns are intense in several locations of the Valley and have an interesting pattern of using the same lands for bricks during the dry season and then conversion to rice during the wet, summer monsoon months. The increase in brick production has contributed to environmental problems including decreased soil productivity, lowered ground water levels, and particularly air pollution. Brick manufacturing has little, if any, effective regulation. There is a lack of current, accurate data on brick production that could be resolved by remote sensing methods. Controls should be established and more information acquired on the location and impacts of brick production.  相似文献   
856.
Air protection agencies in the United States increasingly confront non-attainment of air quality standards for multiple pollutants sharing interrelated emission origins. Traditional approaches to attainment planning face important limitations that are magnified in the multipollutant context. Recognizing those limitations, the Georgia Environmental Protection Division has adopted an integrated framework to address ozone, fine particulate matter, and regional haze in the state. Rather than applying atmospheric modeling merely as a final check of an overall strategy, photochemical sensitivity analysis is conducted upfront to compare the effectiveness of controlling various precursor emission species and source regions. Emerging software enables the modeling of health benefits and associated economic valuations resulting from air pollution control. Photochemical sensitivity and health benefits analyses, applied together with traditional cost and feasibility assessments, provide a more comprehensive characterization of the implications of various control options. The fuller characterization both informs the selection of control options and facilitates the communication of impacts to affected stakeholders and the public. Although the integrated framework represents a clear improvement over previous attainment-planning efforts, key remaining shortcomings are also discussed.  相似文献   
857.
草分枝杆菌及其吸附Pb2+后的可浮性研究   总被引:5,自引:0,他引:5  
周东琴  魏德洲 《环境科学》2006,27(2):338-342
用草分枝杆菌作吸附剂,探讨了采用生物吸附-浮选法去除水中Pb2+的可能性,并对吸附剂与捕收剂的作用机理进行了分析.草分枝杆菌的浮选试验结果表明,阳离子型捕收剂对草分枝杆菌的捕收能力明显比阴离子型捕收剂的强.草分枝杆菌的吸附-浮选试验结果表明,浮选过程可在10min左右达到终点,pH在4~7时,阳离子型捕收剂对草分枝杆菌有较好的浮选去除率,Pb2+去除率也很高.当二正丁胺的浓度为45mmol/L,pH=4.75时,草分枝杆菌和Pb2+的去除率分别达到92%和98%.动电位测试表明,草分枝杆菌的等电点为pH=3.09;吸附Pb2+或与二正丁胺发生作用后,草分枝杆菌的等电点均有所增加.草分枝杆菌细胞壁表面具有较强的负电性,使得阳离子捕收剂对其具有较强的捕收能力,这对采用生物吸附-浮选法去除废水中的重金属离子可能会有重要意义.  相似文献   
858.
Multivariate statistical techniques are applied to particulate matter (PM) and meteorological data to identify the sources responsible for evening PM spikes at Sunland Park, NM (USA). The statistical techniques applied are principal components analysis (PCA), redundancy analysis (RDA), and absolute principal components scores analysis (APCSA), and the data evaluated are 3-h average (6–9 p.m.) PM2.5 mass and chemical composition and 1-h average PM2.5 and PM10 mass and environmental data collected in the winter of 2002. Although the interpretation of the data was complicated by the presence of sources which are likely changing in time (e.g. brick kilns), the multivariate analyses indicate that the evening high PM2.5 is associated with burning-activities occurring to the south of Sunland Park, and these emissions are characterized by elevated Sb, Cl, and elemental carbon; 68% of the PM2.5 mass can be attributed to this source. The PM10 evening peaks, on the other hand, are mainly caused by resuspended dust generated by vehicular movements south of the site and transported by the local terrain-induced drainage flow.  相似文献   
859.
Capacity limits on the air traffic management (ATM) system are of global concern. One solution to increase the efficiency of existing ATM system is through the implementation of advanced automation. However, past experience suggests ATCOs are selective and critical about the forms of automation they are given. Therefore, this study aimed to determine if a threshold or tipping point exists, a point after which users (Air Traffic Control Operators; ATCOs) of automation are no longer willing to accept or cooperate with the automation. 500 Air Traffic Control Operators completed an on-line survey that comprised a series of demographic questions as well as two hypothetical but plausible futuristic air traffic management tools. Each tool contained seven different situations involving different levels of automation involvement ranging from fully manual operation to fully automated. Participants were asked to rate on a five point Likert scale the extent to which they agreed with the statements describing their interaction with the new tools. The results revealed a ‘tipping point’ in automation acceptance/rejection reflecting the point where the applied level of automation shifted the locus of decision-making away from the operator. The results are discussed from a theoretical and applied perspective.  相似文献   
860.
Mechanical–biological treatments (MBTs) of urban waste are growing in popularity in many European countries. Recent studies pointed out that their contribution in terms of volatile organic compounds (VOCs) and other air pollutants is not negligible. Compared to classical removal technologies, non-thermal plasmas (NTP) showed better performances and low energy consumption when applied to treat lowly concentrated streams. Therefore, to study the feasibility of the application of NTP to MBTs, a Dielectric Barrier Discharge reactor was applied to treat a mixture of air and methyl ethyl ketone (MEK), to simulate emissions from MBTs. The removal efficiency of MEK was linearly dependent upon time, power and specific input energy. Only 2–4% of MEK was converted to carbon dioxide (CO2), the remaining carbon being involved in the formation of byproducts (methyl nitrate and 2,3-butanedione, especially). For future development of pilot-scale reactors, acting on residence time, power, convective flow and catalysts will help finding a compromise between energy consumption, desired abatement and selectivity to CO2.  相似文献   
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