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881.
技术减排措施协同控制效应评价研究 总被引:4,自引:0,他引:4
随着我国污染减排形势的日益严峻,采用协同控制措施实现多种污染物控制目标逐渐成为一种趋势,而合理评价减排措施的协同效应是正确选择协同控制措施和制定协同控制规划方案的基础.本研究首次从环境-经济-技术角度系统地提出了技术减排措施的协同控制效应评价方法,并以火电行业为案例进行分析.采用协同控制效应坐标系、污染物减排量交叉弹性(Elsa/b)分析和单位污染物减排成本等方法评价技术减排措施对SO2 、NO,和CO2的协同控制效应,三种评价方法相互配合,可以帮助我们从多角度检验不同减排措施的协同效果.对火电行业技术减排措施进行协同控制效应坐标系和污染物减排量交叉弹性分析的结果表明,末端治理措施不具有协同性,而前端控制措施和过程控制措施具有较好的协同性.单位污染物减排成本评价的结果表明,末端治理措施优先度排序靠后,而前端控制措施和过程控制措施排序靠前,且针对不同污染物的排序结果有所不同.在进行协同减排方案设计和规划时,应根据决策需要选择适宜的评价方法,参考评价结果选择最为成本有效的措施. 相似文献
882.
The aqueous solubility of hexafluorobenzene has been determined, at 298.15 K, using a shake-flask method with a spectrophotometric quantification technique. Furthermore, the solubility of hexafluorobenzene in saline aqueous solutions, at distinct salt concentrations, has been measured. Both salting-in and salting-out effects were observed and found to be dependent on the nature of the cationic/anionic composition of the salt. COSMO-RS, the Conductor-like Screening Model for Real Solvents, has been used to predict the corresponding aqueous solubilities at conditions similar to those used experimentally. The prediction results showed that the COSMO-RS approach is suitable for the prediction of salting-in/-out effects. The salting-in/-out phenomena have been rationalized with the support of COSMO-RS σ-profiles. The prediction potential of COSMO-RS regarding aqueous solubilities and octanol-water partition coefficients has been compared with typically used QSPR-based methods. Up to now, the absence of accurate solubility data for hexafluorobenzene hampered the calculation of the respective partition coefficients. Combining available accurate vapor pressure data with the experimentally determined water solubility, a novel air-water partition coefficient has been derived. 相似文献
883.
Carbamazepine is a psychiatric pharmaceutical widely detected in aquatic environments. Due to its generalized occurrence and environmental persistence it might be considered as an anthropogenic pollution indicator. In this research, a previously developed enzyme-linked immunosorbent assay (ELISA), based on a commercial monoclonal antibody, was applied to the quantification of carbamazepine in ground, surface and wastewaters and results were validated by liquid chromatography-tandem mass spectrometry (LC-MS/MS).The performance of the applied ELISA methodology was tested in the presence of high concentrations of sodium chloride and dissolved organic matter. The method was not significantly affected by matrix effects, being adequate for the quantification of carbamazepine in environmental samples, even without sample pre-treatment. This method allows the quantification of carbamazepine in the range of 0.03-10 μg L−1, with a relative error lower than 30%. Due to a pH dependent cross-reactivity with cetirizine, an antihistaminic drug, the assay also enabled the quantification of cetirizine in the samples.The application of the developed method to the quantification of carbamazepine was performed by using environmental samples with very different matrices, collected in the geographical area of Ria de Aveiro, an estuarine system located in the North of Portugal. Carbamazepine was detected in all analyzed wastewater samples and in one surface water with concentrations between 0.1 and 0.7 μg L−1. Validation with LC-MS/MS revealed that results obtained by ELISA are 2-28% overestimated, which was considered highly satisfactory due to the absence of sample pre-treatments. 相似文献
884.
We measured heavy metal concentrations in yellow-legged gulls (n = 196) and European shags (n = 189) in order to assess the temporal pattern of contaminant exposure following the Prestige oil spill in November 2002. We analysed Pb, Cu, Zn, Cr, Ni and V levels in chick feathers sampled at four colonies during seven post-spill years (2003-2009), and compared results with pre-spill levels obtained from feathers of juvenile shag corpses (grown in spring/summer 2002). Following the Prestige wreck, Cu (4.3-10 μg g−1) and Pb concentrations (1.0-1.4 μg g−1) were, respectively, between two and five times higher than pre-spill levels (1.5-3.6 and 0.1-0.4 μg g−1), but returned to previous background concentrations after three years. Our study highlights the suitability of chick feathers of seabirds for assessing the impact of oil spills on heavy metal contamination, and provides the best evidence to date on the persistence of oil pollution after the Prestige incident. 相似文献
885.
886.
Nelson SJ Johnson KB Kahl JS Haines TA Fernandez IJ 《Environmental monitoring and assessment》2007,126(1-3):69-80
Precipitation and streamwater samples were collected from 16 November 1999 to 17 November 2000 in two watersheds at Acadia
National Park, Maine, and analyzed for mercury (Hg) and dissolved inorganic nitrogen (DIN, nitrate plus ammonium). Cadillac
Brook watershed burned in a 1947 fire that destroyed vegetation and soil organic matter. We hypothesized that Hg deposition
would be higher at Hadlock Brook (the reference watershed, 10.2 μg/m2/year) than Cadillac (9.4 μg/m2/year) because of the greater scavenging efficiency of the softwood vegetation in Hadlock. We also hypothesized the Hg and
DIN export from Cadillac Brook would be lower than Hadlock Brook because of elemental volatilization during the fire, along
with subsequently lower rates of atmospheric deposition in a watershed with abundant bare soil and bedrock, and regenerating
vegetation. Consistent with these hypotheses, Hg export was lower from Cadillac Brook watershed (0.4 μg/m2/year) than from Hadlock Brook watershed (1.3 μg/m2/year). DIN export from Cadillac Brook (11.5 eq/ha/year) was lower than Hadlock Brook (92.5 eq/ha/year). These data show that
∼50 years following a wildfire there was lower atmospheric deposition due to changes in forest species composition, lower
soil pools, and greater ecosystem retention for both Hg and DIN. 相似文献
887.
小麦异源细胞质遗传效应的比较研究 总被引:5,自引:0,他引:5
本文以稳定的同核异质异核杂种小麦为材料,对小麦属和山羊草属的细胞质遗传效应进行了比较研究,分析了异源细胞质遗传疚的特点,并初步筛选出了一批在小麦雄性不育性应用中以及在小麦核质杂种优势利用中有价值的细胞质材料。 相似文献
888.
采用3种方法研究了铀和铅对枯草杆菌的毒性:(1)试纸法测抑菌圈的直径;(2)血球计数板测细菌菌数;(3)高倍显微镜下观察细菌形态和密度的变化.实验考察铀和铅的质量浓度为1~2 000 mg/L.结果表明:铀和铅对枯草杆菌的生长繁殖有显著影响;铀和铅对枯草杆菌的最大无作用剂量均小于1 mg/L;铀对枯草杆菌的致死质量浓度为500 mg/L,铅对枯草杆菌的致死质量浓度为 1 000 mg/L.同时,对以上3种方法进行了比较,确定了其各自的应用范围,为重金属对微生物毒性研究方法的选择提供了参考. 相似文献
889.
In general, contamination levels tend to be highest close to sources of a chemical and decline with increasing distance as
a result of dilution, dispersion and degradation. However, contrary to this, circumstances have been described when contamination
levels are higher further away from sources than at the sources themselves. Examples are elevated levels of persistent, hydrophobic,
organic chemicals in the Arctic, in mountain regions and in forest soils. In order to address the questions of why and when
such an inversion of environmental levels is occurring, this paper seeks to identify, name and categorise principles of general
validity leading to such behaviour. By compiling and analysing various causes of elevated contamination levels in the environment,
three main categories became apparent, 1. equilibrium partitioning effects, 2. effects resulting from changes in phase composition,
volume or temperature, and 3. dynamic or kinetic effects. These principles are illustrated with several examples. The case
can be made that understanding, quantifying and predicting these causes could provide a general conceptual framework for studying
the fate of chemicals in the environment. 相似文献
890.