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1.
Aerosol constituents (elemental carbon, organic carbon, soluble ions including organic acids, and selected trace metals) were investigated from samples of a field campaign taking place at Bhola Island in the Bay of Bengal (Bangladesh). The campaign took place in the pre-monsoon season (May 2001) using low volume samplers. Carbonaceous material comprised the majority of the analysed components. The average concentrations of EC and OC were 2.8 and 4.6 microg m(-3), respectively. Oxalic acid was the most abundant dicarboxylic acid (average 268 ng m(-3)) followed by malonic and malic acid. The contribution of carboxylic acids-carbon to organic carbon was 2.0%. Average concentrations observed for sulfate and nitrate were 3.7 microg m(-3) and 1.5 microg m(-3). Two different types of aerosol were identified at the rural background site on Bhola Island during southerly synoptic flow by means of trajectory analysis: air masses were transported from the Bay of Bengal to the sampling site in all cases. However, during "Period 1" they experienced longer residence times over the Indian Ocean, while the "Period 2" trajectories came along the Indian coast or passed over the Indian continent. During Period 1 the concentration levels of soluble ions were a factor of 4-6 lower than during Period 2. The concentrations of EC, OC and K differed less than a factor of 1.5 between the two periods. The Period 1 aerosol showed similarities to the haze layers observed during winter-monsoon conditions south of India during the INDOEX experiment. Based on EC/TC and K/EC ratios we find that around 80% of the carbonaceous aerosol from Period 1 in Bhola is from fossil fuel and only around 50% from Period 2. Absolute concentrations of carbonaceous species, soluble ions and trace metals indicate that the background site on Bhola Island is affected by emissions from urbanized regions of Southeast Asia.  相似文献   
2.
Environmental Science and Pollution Research - This study explores the symmetric and asymmetric effects of physical infrastructure on energy consumption, economic growth, and air pollution of...  相似文献   
3.
Environmental Science and Pollution Research - This empirical study investigates the dynamic effects of economic freedom on economic growth and air quality for Pakistan over the period...  相似文献   
4.
Cotton cropping in Pakistan uses substantial quantities of resources and adversely affects the environment with pollutants from the inputs, particularly pesticides. A question remains regarding to what extent the reduction of such environmental impact is possible without compromising the farmers’ income. This paper investigates the environmental, technical, and economic performances of selected irrigated cotton-cropping systems in Punjab to quantify the sustainability of cotton farming and reveal options for improvement. Using mostly primary data, our study quantifies the technical, cost, and environmental efficiencies of different farm sizes. A set of indicators has been computed to reflect these three domains of efficiency using the data envelopment analysis technique. The results indicate that farmers are broadly environmentally inefficient; which primarily results from poor technical inefficiency. Based on an improved input mix, the average potential environmental impact reduction for small, medium, and large farms is 9, 13, and 11 %, respectively, without compromising the economic return. Moreover, the differences in technical, cost, and environmental efficiencies between small and medium and small and large farm sizes were statistically significant. The second-stage regression analysis identifies that the entire farm size significantly affects the efficiencies, whereas exposure to extension and training has positive effects, and the sowing methods significantly affect the technical and environmental efficiencies. Paradoxically, the formal education level is determined to affect the efficiencies negatively. This paper discusses policy interventions that can improve the technical efficiency to ultimately increase the environmental efficiency and reduce the farmers’ operating costs.  相似文献   
5.
Environmental Chemistry Letters - Pesticides contribute to human welfare by reducing vector-borne diseases and protecting crops against pests. Insecticides are the most widely employed pesticides...  相似文献   
6.
Environmental Science and Pollution Research - Various empirical studies have examined the nexus between financial markets, but this study focused on the comovement among prominent markets. Our...  相似文献   
7.
Environmental Science and Pollution Research - Economies that depend on natural resources can experience a resource drag effect when economic growth is limited by constraints on the availability of...  相似文献   
8.
Environmental Science and Pollution Research - The main motivation behind this study is the importance of tourism and ICT industry in the economic development of a country and their potential...  相似文献   
9.
Environmental Science and Pollution Research - This paper examines the impact of shadow economy and environmental policy stringency on energy consumption and economic growth in the case of China...  相似文献   
10.
Environment, Development and Sustainability - Economic, environmental, and social imperatives make sustainability-oriented entrepreneurship an indispensable phenomenon of the day, yet only sparse...  相似文献   
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