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991.
Lawrence F. Keller Craig G. Heatwole James W. Weber 《Journal of the American Water Resources Association》1981,17(4):647-654
: This article examines the willingness and capacity of local districts to control ground water mining of the Ogallala Aquifer in the High Plains. The questions of willingness and capacity were approached through extensive field interviews and a survey of all district board members and managers. The analysis focuses on the policy alternatives board members and managers perceive and how they evaluate these alternatives. Methodologically, the study utilized factor analysis of responses rating the desirability of various policy alternatives to ascertain what alternatives were perceived by the sample. Then the sample's preferences for each of the identified factors were calculated. The results demonstrate that the sample of those who must regulate if ground water mining is to be controlled at the substate level are not oriented to regulatory policies and therefore lack the willingness to deal with ground water mining. 相似文献
992.
利用美国石油协会(API)小呼吸损耗核算新公式对国内某油田4个联合站的采出液沉降罐进行了小呼吸损耗核算,并与实测数据进行了对比分析。分析结果表明,API的核算值与实测值的差别较大,相对误差可达90%以上,原因是国内油田采出液沉降罐的现场工况与API公式的模拟条件差别较大。在数据分析的基础上引入平均液体表面温度和平均气体流速两个影响因子对上述公式进行了修正,并利用修正后的公式对另外两个联合站的沉降罐进行了小呼吸损耗核算,核算结果的相对误差降至10%以下。 相似文献
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The US Army Engineering Research Development Center (ERDC) uses a modified form of the Revised Universal Soil Loss Equation
(RUSLE) to estimate spatially explicit rates of soil erosion by water across military training facilities. One modification
involves the RUSLE support practice factor (P factor), which is used to account for the effect of disturbance by human activities
on erosion rates. Since disturbance from off-road military vehicular traffic moving through complex landscapes varies spatially,
a spatially explicit nonlinear regression model (disturbance model) is used to predict the distribution of P factor values
across a training facility. This research analyzes the uncertainty in this model's disturbance predictions for the Fort Hood
training facility in order to determine both the spatial distribution of prediction uncertainty and the contribution of different
error sources to that uncertainty. This analysis shows that a three-category vegetation map used by the disturbance model
was the greatest source of prediction uncertainty, especially for the map categories shrub and tree. In areas mapped as grass,
modeling error (uncertainty associated with the model parameter estimates) was the largest uncertainty source. These results
indicate that the use of a high-quality vegetation map that is periodically updated to reflect current vegetation distributions,
would produce the greatest reductions in disturbance prediction uncertainty. 相似文献
997.
根据对银洞坡金矿的水质水量调查,采用碱性氯化法处理银洞坡金矿尾矿库的含氰废水,在去除氰化物和重金属方面都取得了较好的效果。对实验的结果进行了影响因素分析,提出了采用间歇式方法处理含氰废水的工艺方案。 相似文献
998.
Necessity of Toxicity Assessment in Turkish Industrial Discharges (Examples from Metal and Textile Industry Effluents) 总被引:2,自引:0,他引:2
Sponza DT 《Environmental monitoring and assessment》2002,73(1):41-66
Toxicity of some organic and inorganic chemicals to microorganisms is an important consideration in assessingtheir environmental impact against their economic benefits.Microorganisms play an important role in several environmentalprocesses, both natural and engineered. Some organic and inorganics at toxic levels have been detected in industrial discharges resulting in plant upsets and discharge permit violations. In addition to this, even though in some cases the effluent wastewater does not exceed the discharge limits,the results of toxicity tests show potential toxicity. Toxicityknowledge of effluents can benefit treatment plant operators inoptimising plant operation, setting pre-treatment standards, and protecting receiving water quality and in establishing sewer discharge permits to safeguard the plant. In the Turkish regulations only toxicity dilution factor (TDF) with fish is part of the toxicity monitoring program of permissible wastewater discharge. In various countries, laboratory studiesinvolving the use of different organisms and protocol for toxicity assessment was conducted involving a number of discharges.In this study, it was aimed to investigate the acute toxicity of textile and metal industry wastewaters by traditional and enrichment toxicity tests and emphasize the importance of toxicity tests in wastewater discharge regulations. The enrichment toxicity tests are novel applications and give anidea whether there is potential toxicity or growth limiting and stimulation conditions. Different organisms were used suchas bacteria (Floc and Coliform bacteria) algae (Chlorella sp.), fish (Lepistes sp.) and protozoan (Vorticella sp.) to represent four tropic levels. The textile industry results showed acute toxicity for at least one organism in 8 out of 23 effluent samples. Acute toxicity for at least two organisms in 7 out of 23 effluent sampling was observed for the metal industry. The toxicity test results were assessed with chemical analyses such as COD, BOD, color and heavy metals. It was observed that the toxicity of the effluents could not be explained by using physicochemical analyses in 5 cases for metal and 4 cases for the textile industries. The results clearly showed that the useof bioassay tests produce additional information about the toxicity potential of industrial discharges and effluents. 相似文献
999.
中国4城市空气颗粒物元素的因子分析 总被引:9,自引:1,他引:9
因子分析在研究空气颗粒物来源上得到了广泛的应用。本文应用最大方差旋转因子分析法对中国4城市空气中粗、细颗粒物元素的来源进行了分析。结果指出粗、细颗粒物因子大致可分为土壤源因子和工业污染源因子两大类。粗颗粒物主要来自土壤源,细颗粒物主要来自工业污染源,并指出土壤源因子对粗颗粒物的贡献大于对细颗粒物的贡献。 相似文献
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