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111.
In this paper we employ a stated preference environmental valuation technique, namely the choice experiment method, to estimate local public’s willingness to pay (WTP) for improvements in the capacity and technology of a sewage treatment plant (STP) in Chandernagore municipality, located on the banks of the River Ganga in India. A pilot choice experiment study is administered to 150 randomly selected Chandernagore residents and the data are analysed using the conditional logit model with interactions. The results reveal that residents of this municipality are willing to pay significant amounts in terms of higher monthly municipality taxes to ensure the full capacity of the STP is used for primary treatment and the technology is upgraded to enable secondary treatment. Overall, the results reported in this paper support increased investments to improve the capacity and technology of STPs to reduce water pollution, and hence environmental and health risks that are currently threatening the sustainability of the economic, cultural and religious values this sacred river generates.  相似文献   
112.
113.
To develop more efficient chemical methods for the demineralization of organic pollutants from water bodies, which one was also mimic to the nature, a degradation of methylene blue by Fe( Ⅲ ) and H2O2 in the absence of light instead of Fe( Ⅱ ) and H2O2 was studied. Results showed that use of Fe ( Ⅲ ) is more promising than Fe( Ⅱ ). The present study reflects that Fenton reaction is more efficient, in the presence of a small amount of salicylic acid is added which is a one of the priority pollutant.  相似文献   
114.
Nutrient Ioadings were measured for surface seawater and bottom sediments of semi-intensive and improved extensive shrimp culture pond, adjacent estuary, and fallow land in the south-east coastal region of Bangladesh during August, 2000--January, 2001 to evaluate the impact of shrimp culture. The mean levels of nutrients found in the pond surface water were 108.780 mg/L for CaCO3, 0.526 mg/L for NH4^ -N, 3.075 wt% for organic carbon, 7.00 mg/L for PO4-P, 5.57 mg/L for NO3-N, and 7.33 mg/L for chlorophyll-a. The maximum mean value of H2S(0.232 mg/L) was found in estuarine water. Nutrients loading were found to be decreased with distance from the shrimp farm discharge unit in estuarine water. The mean level of organic matter, total nitrogen, and organic carbon were found in higher concentrations in sediments of cultured pond compared to bottom soil of adjacent fallow land at the same elevation. Extractable Ca values were found in higher concentration(550.33 ppt) in adjacent fallow land, as the shrimps for molting in shrimp ponds use extractable Ca. The relation between seawater H2S value and sediment pH ( r= -0.94); sediment organic carbon and sediment pH values ( r= -0.76), sediment total nitrogen and sediment pH ( r = - 0.74) were found to be highly negatively correlated. Whereas the relation between seawater H2S value and sediment total nitrogen ( r= 0.92), water NH4^ -N and sediment pH ( r = 0.66) were found to be positively correlated. The results revealed that load of nutrients at eutrophic level in estuarine water, and decrease of soil pH; leading to acid sulphate soil formation indicates a negative impact of shrimp culture.  相似文献   
115.
Alarming environmental pollution from petroleum based non-biodegradable disposable packaging films has generated concern for development of alternatives from natural polymers such as starch. In the present work, the biodegradability of a self-supporting film made from starch and polyvinyl alcohol (PVA) (starch:PVA?=?9:1 as the polymer) together with glutaraldehyde as crosslinker and sodium propionate (SP) as antimicrobial was investigated by soil burial method. The changes in soil composition namely pH, organic carbon, available and total nitrogen, and water holding capacity as a result of biodegradation were also estimated. The film underwent ≈?90% biodegradation within a period of 28 days, with simultaneous increase in soil nutrients. Moreover, the pH remained in the accepted limit for plant growth. Thus, antimicrobial in the film did not hamper its biodegradation, rather disposal of the film in soil might facilitate plant growth.  相似文献   
116.
Decentralized power generation, using locally available biofuels from non-edible oilseeds, is an option for rural electrification in many developing countries. However, due to prevailing high price of non-edible oilseeds, such as Jatropha curcas, the cost of electricity generation is very high. This paper provides detailed financial analysis of straight vegetable oil (SVO)-based decentralized power project and proposes an innovative model for enhancing their financial viability. While for implementing agency operational cost recovery is the key for viability, affordable tariff is crucial for end-users. The paper attempts to estimate minimum desired price of electricity from the stakeholders' (producer and users) perspective using data gathered from selected operational SVO-based power generation projects in India. Analysis carried out in this paper indicates that operating the decentralized power plant at higher capacity utilization factor, by introduction of productive load, and differentiated tariffs for commercial and domestic consumers may not alone be sufficient to achieve the financial viability. The paper proposes an innovative integrated model of using biogas, obtained from the by-product de-oiled cake of non-edible oilseeds, as a feedstock for power generation, instead of using the SVO in engines. This reduces the fuel cost of power generation, thereby helping to bring down the tariff within the paying capacity of rural consumers. The main produce, viz. extracted non-edible oil, which was otherwise used as fuel for generating power, can be sold in local market for earning revenue, thereby enhancing the project’s economic viability. This paper sets forth the proposed integrated model as a viable biofuel-based decentralized power project for sustainable rural development in areas with adequate availability of oilseeds.  相似文献   
117.
Surface ozone is mainly produced by photochemical reactions involving various anthropogenic pollutants, whose emissions are increasing rapidly in India due to fast-growing anthropogenic activities. This study estimates the losses of wheat and rice crop yields using surface ozone observations from a group of 17 sites, for the first time, covering different parts of India. We used the mean ozone for 7 h during the day (M7) and accumulated ozone over a threshold of 40 ppbv (AOT40) metrics for the calculation of crop losses for the northern, eastern, western and southern regions of India. Our estimates show the highest annual loss of wheat (about 9 million ton) in the northern India, one of the most polluted regions in India, and that of rice (about 2.6 million ton) in the eastern region. The total all India annual loss of 4.0–14.2 million ton (4.2–15.0%) for wheat and 0.3–6.7 million ton (0.3–6.3%) for rice are estimated. The results show lower crop loss for rice than that of wheat mainly due to lower surface ozone levels during the cropping season after the Indian summer monsoon. These estimates based on a network of observation sites show lower losses than earlier estimates based on limited observations and much lower losses compared to global model estimates. However, these losses are slightly higher compared to a regional model estimate. Further, the results show large differences in the loss rates of both the two crops using the M7 and AOT40 metrics. This study also confirms that AOT40 cannot be fit with a linear relation over the Indian region and suggests for the need of new metrics that are based on factors suitable for this region.  相似文献   
118.
The plastic components from waste mobile phones were sorted and characterized using visual, spectroscopic and thermal methods. The sustainable strength of the recovered plastics was investigated by comparing their mechanical and thermal properties with commercially used reference materials. The results revealed that the recovered polymers have significant potential to be reused. However, some properties, such as impact strength and tensile modulus, are significantly low compared to virgin materials and need further improvement. The samples were also tested for brominated flame retardants (BFRs) using gas chromatography–mass spectrometry technique, and the results indicated the absence of BFR in recovered plastics; hence, these can be processed without any risk of BFR toxicity.  相似文献   
119.
Environment, Development and Sustainability - The present study evaluated the effectiveness of stocking the Gangetic carps, viz. Labeo catla, Labeo rohita, and Cirrhinus mrigala, in a large...  相似文献   
120.
Environmental Science and Pollution Research - Delhi has been identified as one of the highly polluted cities in the world and recently associated with the highest population weighted PM2.5...  相似文献   
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