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331.
Environmental Science and Pollution Research - Coronavirus refers to a group of widespread viruses. The name refers to the specific morphology of these viruses because their spikes look like a...  相似文献   
332.

Water scarcity necessitates a cost-effective and productive solution. This study focused to enhance the productivity of single slope solar still by incorporating the better weight of palm flower powder (micro-sized) in the basin and micro phase change material heat storage bed under the basin. In this aspect, the different quantity of palm powder weights such as 10, 30, 50, 70, 100, 120 and 150 g in the basin was experimentally examined. The absorber basin containing 50 g of palm powder has better productivity of 37.25%, whereas for 10, 30, 70, 100, 120 and 150 g, they were 11.85, 24.78, 36.8, 33.05, 10.25 and ? 20.22% respectively. The influence of palm powder with different weight% impregnated in the paraffin wax was analysed. The maximum thermal conductivity of 0.33 W/m K was obtained in the sample containing palm flower powder of 20 wt%. The experimental investigation was carried out with 50 g of micro-sized palm powder in the basin and thermal storage bed under the basin containing 20 wt% of micro phase change material (PCMPFP-SS) and conventional solar still (CSS). The overall distillate output of PCMPFP-SS was 4670 and 4250 mL/m2 on day 1 and day 2 respectively. On the other hand, the overall distillate output for CSS was 3030 and 2800 mL/m2 on day 1 and day 2. From the economic analysis, it was found that the cost per litre (CPL) of PCMPFP-SS and CSS was $ 0.025 and $ 0.032 respectively. Moreover, the payback period of PCMPFP-SS was lowered from 5.1 to 4.1 months compared to CSS.

  相似文献   
333.
Environmental Science and Pollution Research - Medicinal plants have been used as traditional herbal medicines in the treatment of various types of diseases. However, the increased demand for these...  相似文献   
334.
Environmental Science and Pollution Research - Neurodegeneration is the loss of neuronal capacity and structure over time which causes neurodegenerative disorders like Alzheimer, amyotrophic...  相似文献   
335.
The removal of solubilized vat dye effluent using photo detoxification method was studied at various pH ranges. Experiments were carried out with synthetic effluent using total dye concentrations of 50, 100, 200, 300, and 350 mg/L. In sunlight photo oxidation, the original soluble vat dye is precipitated and can be filtered and reused by the textile industries. The effect of the different concentrations (1,000, 2,000, 3,000 mg/L) of total dissolved solids on the removal of vat dye was also carried out in the photo detoxification process. The efficiency of the dye removal was found to be 99 %.  相似文献   
336.
Fluoride concentration of groundwater reserves occurs in many places in the world. A critical area for such contamination in India is alluvial soil of the plain region, consisting of five blocks (Jhajjar, Bahadurgarh, Beri, Matanhail, and Sahalawas) of the Jhajjar District adjacent to the National Capital Territory of India, New Delhi. The purpose of this study was to assess the association between water fluoride levels and prevalence of dental fluorosis among school children of the Jhajjar District of Haryana, India. The fluoride content in underground drinking water sources was found to vary in villages. Hence, the villages were categorized as high-fluoride villages (1.52–4.0 mg F/l) and low/normal-fluoride villages (0.30–1.0 mg F/l). The source of dental fluorosis data was school-going children (7–15 years) showing different stages and types of fluorosis who were permanent resident of these villages. The fraction of dental fluorosis-affected children varied from 30% to 94.85% in the high-fluoride villages and from 8.80% to 28.20% in the low/normal-fluoride villages. The results of the present study revealed that there existed a significant positive correlation between fluoride concentration in drinking water and dental fluorosis in high-fluoride villages (r = 0.508; p < 0.001) and insignificant correlation in low-fluoride villages.  相似文献   
337.
Various agricultural and kitchen waste residues were assessed for their ability to support the production of a complete cellulase system by Aspergillus niger NS-2 in solid state fermentation. Untreated as well as acid and base-pretreated substrates including corn cobs, carrot peelings, composite, grass, leaves, orange peelings, pineapple peelings, potato peelings, rice husk, sugarcane bagasse, saw dust, wheat bran, wheat straw, simply moistened with water, were found to be well suited for the organism's growth, producing good amounts of cellulases after 96 h without the supplementation of additional nutritional sources. Yields of cellulases were higher in alkali treated substrates as compared to acid treated and untreated substrates except in wheat bran. Of all the substrates tested, wheat bran appeared to be the best suited substrate producing appreciable yields of CMCase, FPase and β-glucosidase at the levels of 310, 17 and 33 U/g dry substrate respectively. An evaluation of various environmental parameters demonstrated that appreciable levels of cellulases could be produced over a wide range of temperatures (20-50 °C) and pH levels (3.0-8.0) with a 1:1.5 to 1:1.75 substrate to moisture ratio.  相似文献   
338.
During 24 and 48 hr of exposure, the digestive glands of Lymnaea treated with a lethal concentration of 0.038 mgl(-1) CuSO4 revealed intense activity of acid phosphatase in perilobular margin. On the other hand, same area of the gland showed moderate activity of ATPase during 24 and 48 hr of exposure. However, alkaline phosphatase showed average activity in perialveolar region and perilobular margin during 24 and 48, and 72 hr of exposure respectively The changes in the activity of these enzymes were nonsignificant in alveolar margin and perialveolar region of the gland. It is interesting to note moderate activity of acid phosphatase in perialveolar region during 24 hr of exposure.  相似文献   
339.
The actinomycete strain LA-29 isolated from the gut contents of the fish, Mugil cephalus of the Vellar estuary showed excellent L-asparaginase activity The enzyme was purified 18-fold and the final recovery of protein was 1.9%, which exhibited an activity of 13.57 IU/mg protein. The partially purified L-asparaginase inhibited the growth of leukemia cells in male wistar rats. Average survival period of the rats was more in an optimum enzyme dose of 100 units and the survival period was less when the dosages were increased and at the same time the enzyme became less effective when the dosages were decreased. Higher survival of 17.2 days was recorded when 100 units of the enzyme was given in three intermittent doses (50/25/25 units) at the interval of 24 hr. Analysis of cell components of the strain LA-29 has revealed the wall type-I which is the characteristic of the genus Streptomyces. Further the morphological, physiological and biochemical features along with the micromorphological results obtained for the strain LA-29 were compared with that of the Streptomyces species found in Bergey's Manual of Determinative Bacteriology and the strain LA-29 has been tentatively identified as Streptomyces canus.  相似文献   
340.
Heavy metals disposed through anthropogenic activities find their way into the oceans and seas through the rivers or through direct fall out from factory effluents. These heavy metals resuspend back into the water column along with the sediments and are known to affect the marine animals. Marine animals like fish, prawn, crab and mussel were collected along the East Coast (off Pulicat lake to Chennai Harbour) to evaluate trace metal concentrations in various tissues. The above specimens accumulated heavy metals such as Zn, Pb, Cu, Co, Cr, Ni and Cd. Fish, prawn, crab and mussel revealed higher concentration of heavy metals such as Zn, Pb, Cr Co, Cu and Ni and Cd in low levels. The results revealed that the heavy metal concentrations in the marine animals are below the threshold levels associated with the toxicological effects and the regulatory limits. The bioconcentration factors revealed that the animals have accumulated heavy metals along the food chain rather than from the water column and sediment.  相似文献   
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