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151.
Studies on the primary biodegradation of linear dodecylbenzene sulfonate, linear dodecyltoluene sulfonate, linear C(10-14) benzene sulfonate, linear C(10-14) toluene sulfonate, commercial samples of linear C(10-14) benzene sulfonate and branched dodecylbenzene sulfonate (DDBS) were carried out using a microbial culture developed from garden soil. Results show that linear alkyl toluene (LAT) is as degradable as linear alkylbenzene (LAB) in 7 days. However, a slower rate of degradation was noted with LAT. Various distributions of the positional isomers of the phenyl ring in the alkane chain of C(10-14) LAB showed no change in the pattern of primary biodegradation.  相似文献   
152.
Human milk samples collected from areas having intensive cotton cultivation and sparse cotton cultivation in Punjab (India) were analysed for organochlorine insecticides. Both DDT and HCH were detected in almost all the samples analysed. The average levels of Sigma-DDT and Sigma-HCH residues in samples from cotton-growing areas were significantly higher than in those from areas where cotton is sparsely grown. Residues of Sigma-DDT mainly comprised p,p'-DDT and p,p'-DDE, while those of Sigma-HCH residues were mainly in the form of its beta-isomer. Median values of 0.52 microg g(-1) of Sigma-DDT and 0.19 microg g(-1) of Sigma-HCH in samples of human milk from cotton-growing areas of Punjab (India) were higher than those reported from most other countries in the World.  相似文献   
153.
Eggplant samples were analyzed for endosulfan residues using ELISA, a technique recognized as a promising tool for screening environmental contaminants. Calibration curve for endosulfan was standardized using kits developed by CFTRI Mysore. Farm gate samples of eggplant from 12 different locations were analyzed. The matrix effect was removed by charcoal clean-up. The results were compared with gas chromatographic (GC) analysis. The residues in different samples were in the range of 5-226 ppb. Correlation coefficient between the two methods was found to be 0.98.  相似文献   
154.
155.
Agrawal SB  Singh A  Rathore D 《Chemosphere》2005,61(2):218-228
A field study was conducted to evaluate the suitability of ethylene diurea (N-[2-(2-oxo-1-imidazolidinyl)ethyl]-N'-phenylurea; EDU) in assessing the impact of O3 on mung bean plants (Vigna radiata L. var. Malviya Jyoti) grown in suburban area of Allahabad city situated in a dry tropical region of India. EDU is a synthetic chemical having anti-ozonant property. Mean monthly O3 concentration varied between 64 and 69 microg m(-3) during the experimental period. In comparison to EDU-treated plants, non-EDU-treated plants showed significant reductions in plant growth and yield under ambient conditions. Significant favourable effects of EDU-application were observed with respect to photosynthetic pigments, soluble protein, ascorbic acid and phenol contents. EDU-treated plants maintained higher levels of pigments, protein and ascorbic acid in foliage as compared to non-EDU-treated ones. The study clearly demonstrated that EDU alleviates the unfavourable effects of O3 on mung bean plants, and therefore can be used as a tool to assess the growth and yield losses in areas having higher O3 concentrations.  相似文献   
156.
Tripathi RD  Vajpayee P  Singh N  Rai UN  Kumar A  Ali MB  Kumar B  Yunus M 《Chemosphere》2004,54(11):1581-1588
Plants of Cassia siamea Lamk were grown in garden soil (control), fly-ash (100%) and fly-ash amended by various ameliorants (cowdung manure, press-mud, garden soil; 1:1, w/w). The plants survived in fly-ash (100%) though their growth was less in comparison to the treatments. Fly-ash+press-mud (1:1, w/w) proved to be the best combination as growth (total biomass, leaf number, photosynthetic area, total chlorophyll and protein) was significantly high in this treatment followed by cowdung manure and garden soil. Leaves and roots accumulated significant amount of Cu, Zn, Ni and and Fe. However, the concentration of all the metals was more in roots than leaves except Ni. Although, fly-ash contains high amount of metals but the metal uptake was more in the plants grown in fly-ash+press-mud mixture. Inspite of high metal availability in fly-ash and press-mud mixture, plant growth was good. This might be attributed to the some metal detoxification mechanism active in this treatment. The present study concluded that C. siamea seems to be a suitable plant for developing a vegetation cover on fly-ash dumps.  相似文献   
157.
Laser-induced breakdown spectroscopy (LIBS) has been evaluated as a multimetal continuous emissions monitor (CEM) at the U.S. Environmental Protection Agency (EPA) rotary kiln incinerator simulator (RKIS) facility in Raleigh, NC. Two detection systems with a bifurcated optical fiber bundle were used for simultaneously monitoring the concentrations of Be, Cd, Cr, and Hg in the test. Two calibration techniques were evaluated in the laboratory for the field measurements. On-line calibration of relative metal concentration was also performed in the simulated incinerator gas stream. Toxic metal concentrations measured with LIBS have been compared with the EPA reference method (RM) results.  相似文献   
158.
Insecticide residues in cotton crop soil   总被引:2,自引:0,他引:2  
Dimethoate, monocrotophos, triazophos, deltamethrin, cypermethrin and endosulfan were applied to a cotton crop soil located at Nurpur village, Punjab, India. The insecticides were applied sequentially at recommended dosages in cotton fields by foliar application in 1995, 1996 and 1998. Soil samples were collected from the cotton crop farms and extracted with acetone. The extracted material was analysed by a gas liquid chromatograph (GLC) equipped with an 63Ni electron-capture detector (ECD-63Ni). Recovery data was obtained by fortifying soil with insecticide. The average recoveries from the fortified soil samples were 76-92% for organophosphorous compounds and 90-98% for synthetic pyrethroids and organochlorines. The results showed that the insecticide residues under study were present in the range of 1.16 to 41.97 ng g(-1) d.wt.soil. The pattern of dissipation of the insecticides used was similar for the duration of the crop. Half lives of the insecticides ranged from 7 to 22 days. Except endosulfan none of the other insecticides used were leached below 15 cm. Endosulfan was found to be rapidly degraded in the soil and formed a sulfate metabolite. Persistence and dissipation pattern in soils with history of exposure to the insecticide compared to non-history soils were similar.  相似文献   
159.
The effect of five concentrations (10 mM, 1 mM, 0.1 mM, 0.01 mM and 0.001 mM) of mercury on the rate of absorption of glucose, fructose, glycine and tryptophan by the intestine of the fresh water murrel Channapunctatus has been studied. Intestinal absorption of these nutrients was also examined in fish exposed to a sublethal concentration (3 μg/l) of mercury for 15 and 30 days. Significant decrease was recorded in the rate of intestinal absorption of all the four nutrients with higher concentrations (10 mM, 1 mM and 0.1 mM) of mercury. 0.01 mM and 0.001 mM of mercury also reduced the transport rate but it was insignificant, except in case of tryptophan, where 0.01 mM of mercury also produced significant decrease. Exposure of fish by bath to mercury also resulted in significant decrease in the intestinal transport rate of all the four nutrients after 30 days.  相似文献   
160.
Objective: India has been slow in implementing a central emergency medical services (EMS) system across the country. “108 services” is one of the most popular services that is functional under the public–private partnership model. Limited available literature shows that despite access to services, many traffic crash victims are transported using private vehicles. The objective of this study is to understand the effectiveness of 108 services from a traffic safety perspective.

Method: A questionnaire survey is conducted to understand the awareness of EMS and their function. Using traffic-related fatalities as the dependent variable, a fixed effect panel data model is developed to analyze the effectiveness of the 108 services in improving the traffic safety.

Results: The results from the survey show that, in general, people are not aware of the 108 services. A majority of the population prefers taking victims to the hospital using their personal vehicles or any other vehicles available compared to calling an ambulance. Results from panel data analysis show that despite having an efficient system, these services failed to make significant improvement in the safety of road users in the states in which their services were subscribed.

Discussion: The lack of awareness of an important safety service is alarming. This could be a major reason for lower utilization of 108 services for transporting victims of traffic crashes. This article shows the importance of having efficient awareness campaigns to improve the efficiency of any similar programs that are aimed to enhance the safety of a region.  相似文献   

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