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281.
Organophosphorous compounds (OP) have largely been used as pesticides globally. These chemicals induce oxidative stress as a possible mechanism of action, which has been a focus of toxicological research for the last decade. This review evaluated the presence of oxidative stress, balance between total antioxidant capacity, and oxygen free radicals associated with OP compound exposure. Oxidative stress induced by OP leads to disturbances in function of different organs and tissues. Evidence indicates that stimulation of free radical production, induction of lipid peroxidation, and disturbance of the total antioxidant capacity are mechanisms of toxicity induced by most OP. Thus, use of antioxidants may be beneficial in treatment of OP poisoning, which remains to be elucidated with further clinical trials. 相似文献
282.
In order to maintain the water quality of moving streams, it is essential to know the process of pollutant mixing. The transverse mixing is very important which is needed to be modeled to understand mixing phenomenon. It was observed that transverse mixing is a strong function of secondary currents, thus, submerged vanes, which are aerofoil skewed at angle of 10°–40° with respect to flow, generate transverse circulations that can be utilized to induce secondary currents in the flow to enhance transverse mixing. Present study is an attempt to utilize submerged vanes as an instrument to enhance the transverse mixing by incorporating various vane configurations. In order to study the effect of vane generated circulations on transverse mixing, experimentations were conducted on three vane sizes and for various row arrangements of vanes attached to bed. An attempt is made to investigate the effect of submerged vane size and rows on transverse velocity, concentration profile and transverse mixing coefficient. It was observed by measurement of concentration profile that transverse mixing was more enhanced for submerged vanes of higher height. It was also observed that as the number of rows is proportional to the transverse mixing. By measuring the transverse velocity profile, it was observed that more and more fluid was advected in transverse direction for higher rows of vanes. By utilizing the observed transverse mixing coefficients, number of vane rows and relative height of vane, a predictor was derived to predict transverse mixing coefficient in the presence of submerged vane rows. It was observed that the derived predictor shows a fair amount of agreement in the result predicted. 相似文献
283.
A new digenetic trematode, collected 1969–1970 at Ratnagiri (India) from the marine eel Leptocephalus conger, is described as Indostomachicola kinnei n. g., n. sp. The new genus differs from Stomachicola Yamaguti, 1934 and Allostomachicola Yamaguti, 1958 in many characteristics. The new species is characterized by an unlobed ovary, absence of receptaculum seminis, and presence of post-acetabular seminal vesicle and a ventral pit. 相似文献
284.
Summary
A study was conducted to analyse the causes of death during the period January 1985 to December 1989, in pashmina kids and goats thought to be acclimatised to a medium altitude climate. In general, mortality was higher during the rainy season (up to 62 percent) than in the winter (17 percent) and summer seasons (21 percent). An exception was the year 1987 when mortality was lowest in the rainy season, presumably due to the effects of a drought. During the rainy season the majority of 6–12 month-old kids became dull, off-feed, weak, emaciated and anaemic. Occasionally these animals showed nasal discharge and diarrhoea. Haematological examination of randomly selected animals during rainy, post-rainy and early-winter seasons in 1985, 1986 and 1989 showed very low red blood cell counts (RBC), haemoglobin (Hb) and packed cell volume (PCV); with elevated erythrocytic sedimentation rates (ESR), neutrophilia, relative lymphopaenia, eosinopaenia, hypoproteinaemia, hypoalbuminaemia, hypogamaglobinaemia, increased A:G ratio and hypoglycemia. Red blood cells showed piokilocytosis, anisocytosis, punched out or ring shapes, presence of erythroblasts, basophilic stippling and Anaplasma marginale.Post-mortem examination revealed lesions of parasites either singly or in combination. These included lice, coccidia, Moniezia expansa, Haemonchus contortus,and Trichuris ovis.Poor or slightly improved health state, anaemic blood picture and moderated mortality were witnessed 45 days post-treatment or during the post-rainy season. Early-winter studies indicated that the goats were in an excellent health condition with normal blood picture and negligible mortality.
It was concluded that the higher mortality in pashmina goats during the rainy season was association with high rainfall, humidity, partial or zero grazing, confinement of goats in sheds (all environmental stresses) and parasitism. This was supported in 1987, when the lowest mortality occurred during the rainy season due to the effect of drought and the absence of environmental stresses.Dr R. Somvanshi is a veterinary pathologist and is in charge of the Clinical Pathology and Medicine Section of Livestock Production Research. Dr J.C. Biswas works in the Animal Genetics and Breeding Laboratory. Dr B. Sharma is a biochemist in the Division of virology and currently a post-doctoral fellow at the Department of Virology at the Karolinska Institute, Stockholm, S-10521, Sweden. Dr G.L. Koul works in the Animal Genetics and Breeding Laboratory as Principal Scientist. All are based at the Indian Veterinary Research Institute. 相似文献
285.
Distillery effluent can be converted into biogas and the residue can be utilized as a fertilizer if it is detoxified. Several nitrifying bacteria were screened for detoxification of distillery effluent rich in chloride, nitrogen compounds, free ammonia and monovalent cations. Nitrosococcus oceanus collected from a brackish water lake (Chilka, Orrisa) was noticed to be a potential candidate for detoxification of distillery effluent. The detoxified distillery effluent was used in rice plant culture. The growth and development of rice plants was examined in terms of DCPIP—Hill activity, total carbohydrate, total protein and biomass of rice plants. The detoxified effluent-treated rice plants showed better growth and development as compared with control plant grown in full nutrient solution (Hoagland solution). 相似文献
286.
A number of chlorinated derivatives of phenols, catechols, guaiacols, syringaldehydes, have been detected and their concentrations estimated, using gas chromatography in the chlorination (C) and extraction (E) stage of spent bleach liquor generated in the laboratory by bleaching rice-straw soda pulp. The concentration of various compounds detected have also been compared with their reported 96LC50 values. 相似文献
287.
Flocculants—an Ecofriendly Approach 总被引:2,自引:0,他引:2
B. R. Sharma N. C. Dhuldhoya U. C. Merchant 《Journal of Polymers and the Environment》2006,14(2):195-202
Although water-soluble synthetic polymers find wide applications as flocculants, the potential problem associated with their use is lack of biodegradability and high cost. Polysaccharides owing to their distinctive features like ability to undergo different chemical reactions, biodegradability and sustainability inspire hope to obtain effective, economical viable and safe substitute of the synthetic flocculants. In this regard, chemical modification of Cassia tora and guar gum was carried out through different substitution and grafting reactions. The modified products were tested against kaolin under laboratory conditions vis-a-vis polyacrylamide based synthetic flocculant. 相似文献
288.
289.
Resource conservation strategies for rice‐wheat cropping systems on partially reclaimed sodic soils of the Indo‐Gangetic region,and their effects on soil carbon
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V.K. Mishra S. Srivastava A.K. Bhardwaj D.K. Sharma Y.P. Singh A.K. Nayak 《Natural resources forum》2015,39(2):110-122
The Indo‐Gangetic plain is characterized by intensive agriculture, largely by resource‐poor small and marginal farmers. Vast swathes of salt‐affected areas in the region provide both challenges and opportunities to bolster food security and sequester carbon after reclamation. Sustainable management of reclaimed soils via resource conservation strategies, such as residue retention, is key to the prosperity of the farmer, as well as increases the efficiency of expensive initiatives to further reclaim sodic land areas, which currently lay barren. After five years of experimentation on resource conservation strategies for rice‐wheat systems on partially reclaimed sodic soils of the Indo‐Gangetic region, we evaluated changes in different soil carbon pools and crop yield. Out of all resource conservation techniques which were tested, rice‐wheat crop residue addition (30% of total production) was most effective in increasing soil organic carbon (SOC). In rice, without crop residue addition (WCR), soils under zero‐tillage with transplanting, summer ploughing with transplanting and direct seeding with brown manuring showed a significant increase in SOC over the control (puddling in rice, conventional tillage in wheat). In these treatments relatively higher levels of carbon were attained in all aggregate fractions compared to the control. Soil aggregate sizes in meso (0.25‐2.0 mm) and macro (2‐8 mm) ranges increased, whereas micro (< 0.25 mm) fractions decreased in soils under zero‐till practices, both with and without crop residue addition. Direct seeding with brown manuring and zero tillage with transplanting also showed an increase of 135% and 95%, respectively, over the control in microbial biomass carbon, without crop residue incorporation. In zero tillage with transplanting treatment, both with and without crop residue showed significant increase in soil carbon sequestration potential. Though the changes in accrued soil carbon did not bring about significant differences in terms of grain yield, overall synthesis in terms of balance between yield and carbon sequestration indicated that summer ploughing with transplanting and zero tillage with transplanting sequestered significantly higher rates of carbon, yet yielded on par with conventional practices. These could be appropriate alternatives to immediately replace conventional tillage and planting practices for rice‐wheat cropping systems in the sodic soils of the Indo‐Gangetic region. 相似文献
290.
Mondal Sanchit Jatrana Anushree Maan Sheetal Sharma Prachi 《Environmental Chemistry Letters》2023,21(4):2171-2197
Environmental Chemistry Letters - The circular economy requires advanced methods to recycle biomass into value-added materials, such as lignin extraction and modification. Here, we review lignin... 相似文献