全文获取类型
收费全文 | 194篇 |
免费 | 10篇 |
国内免费 | 19篇 |
专业分类
安全科学 | 30篇 |
废物处理 | 4篇 |
环保管理 | 38篇 |
综合类 | 73篇 |
基础理论 | 20篇 |
污染及防治 | 20篇 |
评价与监测 | 29篇 |
社会与环境 | 5篇 |
灾害及防治 | 4篇 |
出版年
2023年 | 3篇 |
2022年 | 1篇 |
2021年 | 6篇 |
2020年 | 11篇 |
2019年 | 1篇 |
2018年 | 9篇 |
2017年 | 4篇 |
2016年 | 3篇 |
2015年 | 6篇 |
2014年 | 7篇 |
2013年 | 8篇 |
2012年 | 8篇 |
2011年 | 13篇 |
2010年 | 7篇 |
2009年 | 15篇 |
2008年 | 13篇 |
2007年 | 13篇 |
2006年 | 11篇 |
2005年 | 6篇 |
2004年 | 8篇 |
2003年 | 8篇 |
2002年 | 7篇 |
2001年 | 5篇 |
2000年 | 6篇 |
1999年 | 6篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 9篇 |
1994年 | 7篇 |
1993年 | 4篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1988年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有223条查询结果,搜索用时 15 毫秒
21.
采用气袋直接进样法测定环境和污染源空气中的丙烯腈。结果表明:丙烯腈在0.4~99.5 mg/m3浓度范围内具有良好的线性关系,相关系数为0.999 8。在低、中、高3个添加水平回收率为88.9%~100%,相对标准偏差为0.6%~4.7%,均能较好地满足实验室分析要求。 相似文献
22.
Franck Plourabou Pascal Kurowski Jean-Marc Boffa Jean-Pierre Hulin Stphane Roux 《Journal of contaminant hydrology》2000,46(3-4)
An experimental study of the transport properties of fluid-saturated joints composed of two complementary rough fracture surfaces, translated with respect to each other and brought in contact, is reported. Quantitative roughness measurements on different fractured granite samples show that the surfaces have a self-affine geometry from which the dependence of the mean aperture on the relative displacement of fracture surfaces kept in contact can be predicted. Variations of the hydraulic and electrical conductances of the joint are measured as functions of its mean aperture. A simple parallel plane model accounts for the global trend of the measurements, but significant deviations are observed when a relative lateral displacement of the surfaces is introduced. A theoretical analysis of their origin shows that they are due both to the randomness of the aperture field and to a nonzero local slope of the surface near the injection hole; the corresponding conductivity fluctuation amplitudes have power law and linear variations with the lateral displacement, and are enhanced by the radial injection geometry. 相似文献
23.
建立了水中钼的硫氰酸盐一抗坏血酸体系流动注射分光光度测定法,优化了试验条件。方法在0mg/L~16mg/L范围内线性关系良好,检出限为0.19mg/L,废水样品测定的RSD≤I.6%,加标回收率为96.3%~104%,与国家标准方法的测定结果一致。 相似文献
24.
Qingru Wu Shuxiao Wang Mei Yang Haitao Su Guoliang Li Yi Tang Jiming Hao 《环境科学学报(英文版)》2018,30(6):91-99
Large-scale gold production(LSGP) is one of the five convention-related atmospheric mercury(Hg) emission sources in the Minamata Convention on Mercury. However, field experiments on Hg flows of the whole process of LSGP are limited. To identify the atmospheric Hg emission points and understand Hg emission characteristics of LSGP, Hg flows in two gold smelters were studied. Overall atmospheric Hg emissions accounted for 10%–17% of total Hg outputs and the Hg emission factors for all processes were 7.6–9.6 kg/ton. There were three dominant atmospheric Hg emission points in the studied gold smelters, including the exhaust gas of the roasting process, exhaust gas from the environmental fog collection stack and exhaust gas from the converter of the refining process. Atmospheric Hg emissions from the roasting process only accounted for 16%–29% of total emissions and the rest were emitted from the refining process. The overall Hg speciation profile(gaseous elemental Hg/gaseous oxidized Hg/particulate-bound Hg) for LSGP was 34.1/57.1/8.8. The dominant Hg output byproducts included waste acid, sulfuric acid and cyanide leaching residue. Total Hg outputs from these three byproducts were 80% in smelter A and 84% in smelter B. Our study indicated that previous atmospheric Hg emissions from large-scale gold production might have been overestimated.Hg emission control in LSGP is not especially urgent in China compared to other significant emission sources(e.g., cement plants). Instead, LSGP is a potential Hg release source due to the high Hg output proportions to acid and sludge. 相似文献
25.
26.
River systems as providers of goods and services: a basis for comparing desired and undesired effects of large dam projects 总被引:3,自引:0,他引:3
Brismar A 《Environmental management》2002,29(5):598-609
In developing countries, large dam projects continue to be launched, primarily to secure a time-stable freshwater supply and
to generate hydropower. Meanwhile, calls for environmentally sustainable development put pressure on the dam-building industry
to integrate ecological concerns in project planning and decision-making. Such integration requires environmental impact statements
(EISs) that can communicate the societal implications of the ecological effects in terms that are understandable and useful
to planners and decision-makers.
The purpose of this study is to develop a basic framework for assessing the societal implications of the river ecological
effects expected of a proposed large dam project. The aim is to facilitate a comparison of desired and potential undesired
effects on-site and downstream. The study involves two main tasks: to identify key river goods and services that a river system
may provide, and to analyze how the implementation of a large dam project may alter the on-site capacity and downstream potentials
to derive river goods and services from the river system.
Three river goods and six river services are identified. River goods are defined as extractable partly man-made products and
river services as naturally sustained processes. By four main types of flow manipulations, a large dam project improves the
on-site capacity to derive desired river goods, but simultaneously threatens the provision of desirable river goods and services
downstream. However, by adjusting the site, design, and operational schedule of the proposed dam project, undesirable effects
on river goods and services can be minimized. 相似文献
27.
S. Taku Ide Kristian Jessen Franklin M. Orr Jr. 《International Journal of Greenhouse Gas Control》2007,1(4):481-491
CO2 can be effectively immobilized during CO2 injection into saline aquifers by residual trapping – also known as capillary trapping – a process resulting from capillary snap-off of isolated CO2 bubbles. Simulations of CO2 injection were performed to investigate the interplay of viscous and gravity forces and capillary trapping of CO2. Results of those simulations show that gas injection processes in which gravitational forces are weak compared to viscous forces (low gravity number Ngv) trap significantly more CO2 than do flows with strong gravitational forces relative to the viscous forces (high Ngv). The results also indicate that over a wide range of gravity numbers (Ngv), significant fractions of the trapping of CO2 can occur relatively quickly. The amount of CO2 that is trapped after injection ceases is demonstrated to correlate with Ngv. For some simulated displacements, effects of capillary pressure and aquifer dip angle on the amount and the rate of trapping are reported. Trapping increases when effects of capillary pressure and aquifer inclination are included in the model. Finally we show that injection schemes such as alternating injection of brine and CO2 or brine injection after CO2 injection can also enhance the trapping behavior. 相似文献
28.
讨论了单宽流量横向分布参数b_0和b的范围,并按水位级、断面形和低流速状作了研究。这对无实测流场资料的河流进行污染带计算,具有应用前景。 相似文献
29.
30.