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841.
利用大气采样器采集上海市某工业区焦化厂,电厂和氯碱厂的大气颗粒物(PM10),结果显示,工业区中低环化合物占优势;焦化厂、电厂和氯碱厂含量最高的化合物分别是萘、苊和菲;煤炭燃烧是该工业区焦化厂和电厂多环芳烃的主要来源,氯碱厂多环芳烃可能主要是来自于其上风向的焦化厂,二者可能有弱的相关性;苯并(a)芘含量处于中等污染水平.  相似文献   
842.
Enrichment of lead in respirable suspended particulate matter (RSPM) and exposure of human blood to particulate lead in traffic environment were investigated. Samples of RSPM, non-respirable suspended particulate matter (NRSPM) and total suspended particulate matter (TSPM) were collected in 10 sampling sites located on National Highway No. 6, Durg–Bhilai section of Chhattisgarh State of India. Forty blood samples, out of which 20 of highway traffic personnel with chronic exposure and other 20 of general population who were residing more than 10 km away from the National Highway, were collected. Samples of particulate matter were weighed and analysed for particulate lead. Results have shown a higher concentration of average RSPM and TSPM in all the sampling sites compared to the Indian permissible limits. Geometric mean of lead levels was found in the range of 0.880–1.414 µg/m3 (TSPM) in the study sites. Concentrations of lead in RSPM have shown a higher enrichment (range 2.645–3.171) relative to NRSPM. Blood lead levels in traffic personnel and general population were found in the range of 56.70–101.17 µg/dL and 7.92–31.22 µg/dL, respectively.  相似文献   
843.
太原市大气颗粒物中多环芳烃的分布及污染源识别的研究   总被引:15,自引:0,他引:15  
多环芳烃(PAHs)具有致癌性,研究大气颗粒物中PAHs在不同功能区的分布、变化、来源具有重要意义。对太原市不同功能区大气颗粒物中有机物的研究表明,太原市大气颗粒物中含量较高的多一并主烃有9种,且均不带取代基,平均浓度为189.2ng/m^3,Bap浓度平均为74.7ng/m^3,具体到各功能区浓度分布为:一电厂化工区〉太钢工业区〉桃园三巷商业居民区〉太行仪表厂居民文化区。并利用各种指标判识来源,太  相似文献   
844.
大连市自然降尘与总悬浮微粒的相关分析   总被引:2,自引:0,他引:2  
主要是对大气监测中两个重要监测指标-自然降尘和总悬浮微粒进行相关分析,并找出其内在联系.  相似文献   
845.
研究了重金属Co、Ni、Fe、Mn在长江口及邻近海域悬浮颗粒中的含量、存在形态以及它们在河水与海水混合过程中迁移转化特征,其变化动态特征表明,Co、Ni、Fe以残渣态为主要存在形式;由于Fe-Mn氧化物的形成和吸附作用,使上述金属从水体经过悬浮颗粒转到沉积物中;以Fe-Mn氧化物和碳酸盐形态存在的重金属含量受水体环境的pH和盐度制约。用多元回归分析求得不同形态重金属含量与盐度、pH值和悬浮物含量的变化方程,以及与环境要素间的相互关系。  相似文献   
846.
颗粒物捕集器技术首次应用到港口疏浚监测中,通过对现场疏浚悬浮颗粒物的监测以及对生物的急性半致死浓度的模拟实验研究,建立了一套较完整的疏浚监测系统和技术,可以更有效和直观地反映疏浚过程中对养殖海区生物的影响。现场调查和实验结果表明:在疏浚区和养殖区交界处疏浚悬浮物在海水表面的垂直通量为12.68mg/(cm^2.d),中层为25.41mg/(cm^2.d);在养殖中心区表层为7.58mg/(cm^2  相似文献   
847.
简要分析了柴油机颗粒排放的形成机理,并评述了有关颗粒控制技术的前处理、机内控制和后处理方法。最后,指出有效降低颗粒排放的方向。  相似文献   
848.
混凝研究的理论与实践近三十年来得到长足的发展,很大的原因在于现代检测技术与手段的大力运用,激光光散射为其中得力的方法之一。本文对其基本操作原理作了简要介绍,并对测定过程中存在的若干问题作了探讨。然后就其在混凝领域中诸层次的研究现状与发展趋势进行了若干概括。本文试图阐明其应用于混凝领域的研究所具有的巨大潜力及困难与局限所在,以期将来更大的进展  相似文献   
849.
Goals, Scope and Background Among other substances, sulphur dioxide (SO2), nitric oxide (NO) and nitrogen dioxide (NO2) are parameters which are routinely measured to describe basic air quality. Organic extracts of airborne particulate matter contain mutagenic chemical compounds of different origins. The aim of the study was to find correlations between routine monitoring data and mutagenic activity of organic extracts of simultaneously drawn samples.Methods Specimens were collected over a period of two years at 8 sampling sites in south-west Germany. Simultaneously, concentrations of NO, NO2, and SO2 were measured on-line within the framework of the official air monitoring network of Baden-Württemberg, Germany. Dust samples were collected for biotesting using high volume air samplers equipped with glass fibre filters. After sampling was completed, filters were extracted and samples were prepared for biological testing. Mutagenic activity was tested by means of the plate incorporation assay (Ames test) using S. typhimurium TA98 and TA100 tester strains. During the first year of the study, all tests have been performed with and without metabolic activation. Additionally, a series of tests has been performed in parallel with TA98 and TA98NR.Results and Discussion Comparison of Ames test data obtained with and without metabolic activation indicates no statistically significant difference between both methods. Therefore, during the second year of the study, all tests have been performed without metabolic activation. Average yearly activities at the sampling sites were between 1 und 27 Revertants per m3 (Rev/m3). High activities were preferably found at congested sites (Karlsruhe, up to 95 Rev/m3). However, peak values of over 100 Rev/m3 were found in other places where pollution by traffic is significantly lower. The reason for these high level values is not evident. Tests performed using TA98NR tester strain indicate a significant share (average 31%) of compounds requiring activation by nitroreductase for mutagenic activity. Average mutagenic activity can be correlated to routine monitoring parameters. Comparison of averaged data for particular sampling sites indicates significant correlation between nitric oxide and mutagenic activity in TA98 (r2=0.90), while correlation between nitrogen dioxide (0.84) or sulphur dioxide (0.52) and mutagenic activity is weaker. For TA100, correlations are generally weaker than for TA98. Comparison of data for mutagenic activity and routine monitoring data of distant sites being sampled simultaneously shows parallel behaviour.Conclusions Results from this study show that mutagenic activity can be compared to seasonal and local variations of gaseous indicator air pollutants. Tester strain TA98 generally shows the best correlations. Although pollution by particle-bound mutagenic substances is significantly higher during the cold season than during summer on average, mutagenic activity of airborne dust is not a continuous effect. During winter, peak levels as well as low pollution periods can occur. Even during winter time mutagenic activity can reach very low levels typical for summertime. Comparison of results for distant sampling sites where samples have been collected simultaneously indicate that “classical” indicators of air pollution and bacterial mutagenicity of organic extracts from airborne particulate matter are influenced by connected effects. Seasonal trend of mutagenic activity, in particular, is similar to the concentrations of nitrogen oxide. NO is a strong indicator for vehicle exhaust gases. It is concluded that the average mutagenic activity at particular sites can be estimated using NO concentrations as an indicator.  相似文献   
850.
In this work, stationary and mobile point source tracer release techniques have been used to determine PM10 emission rates from four-lane commercial/residential paved roads under sanded and unsanded conditions, and from unpaved roads relative to site-specific vehicular and ambient parameters. Measured street (4 + lanes; ? 10,000 vehicles per day) emission factors for unsanded and sanded roads were 40 and 20% lower, respectively, than the EPA approved reference value. The sanded road emission factor was approximately 40% higher than that for the unsanded road. These results indicate a consistent relationship between PM10 and relative humidity under unsanded conditions. There is some evidence to suggest that street sweeping has a measurable effect on PM,, emission reduction during periods of low relative humidity (i.e. ? 30%). Within the constraints imposed by the variable experimental conditions, the emission factors determined for unpaved roads agreed reasonably well with the unpaved road empirical formula. Limited correlations were observed with ambient meteorological parameters. The capability of the “upwind-dowiawind” concentration modeling method to predict accurate emission was tested using a Gaussian dispersion model (SIMFLUX). Predictions agreed well with the experimentally determined emission factors.  相似文献   
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