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81.
Heavy metals in respirable suspended particulate matter (RSPM) were analyzed for different seasons, from July 2002 to December 2002, at different locations in Hisar (Haryana, India). The samples were analyzed for Pb, As, Ni, Cu, Mn, Fe and Mg on atomic absorption spectrophotometer (AAS) in air-acetylene flame. The concentration of heavy metals was more in the studied residential area followed by industrial area and commercial area. The concentrations of Fe, As, Ni and Mn were found to be more compared to other metals. Further, the concentrations of all the heavy metals were higher in pre-monsoon (extended summer) and monsoon followed by post-monsoon, autumn and winter. Meteorology played an important role in concentration of heavy metals in RSPM. Turbulent conditions resulted in higher concentration owing to re-suspension and external input whereas, low wind speed, low temperature and high relative humidity favoured low concentration of the pollutants. The evaluation of enrichment factor revealed that Pb, As, Ni, Cu, and Mn are emitted, chiefly from anthropogenic sources and Fe and Mg are associated with natural sources.  相似文献   
82.
Textile mill waste can be vermicomposted if it is mixed in the range of 20–30% with cow dung. This article reports the effect of inoculation, of nitrogen fixing Azotobacter chroococcum strain; Azospirillum brasilense strain and phosphate solubilizing Pseudomonas maltophila, on nitrogen and phosphorus content of vermicomposts prepared from cow dung (CD) and cow dung spiked textile mill sludge (CD + STMS). The CD vermicompost was more supportive to the growth and multiplication of all the three bacteria than CD + STMS vermicompost. In Azotobacter chroococcum treated vermicomposts maximum nitrogen content was recorded between 45 and 60 days [CD␣vermicompost (25.9 ± 0.45 g kg−1) and CD + STMS vermicompost (20.6 ± 0.62 g kg−1)] followed by Azospirillum brasilense inoculation [CD vermicompost (19.4 ± 0.60 g kg−1) and CD + STMS vermicompost (18.6 ± 0.17 g kg−1)]. Phosphorus content in Pseudomonas maltophila inoculated CD vermicompost was 20.8 ± 0.20 g kg−1 and CD + STMS vermicompost was 13.4 ± 0.45 g kg−1 after 75th day of inoculation.  相似文献   
83.
Environmental Science and Pollution Research - Biocovers are known for their role as key facilitator to reduce landfill methane (CH4) emission on improving microbial methane bio-oxidation....  相似文献   
84.
85.
Metal pollution produces damage to marine organisms at the cellular level possibly leading to ecological imbalance. The present investigation focused on the acute and chronic toxicity of lead (Pb) and zinc (Zn) by examining the effects of biomarker enzymes in post-larvae of Penaeus monodon (Tiger prawn). Antioxidant biomarker responses such as lipid peroxidation (LPO) and catalase (CAT) activity for Pb and Zn were determined following chronic exposure. Acute Lethal Concentration 50 (LC50) values observed in the study at 96?h for Pb and Zn at 5.77?±?0.32?mg?L?1 and 3.02?±?0.82?mg?L?1, respectively. The estimated No Observed Effect Concentration and Lowest Observed Effect Concentration values for Pb were 0.014 and 0.029?mg?L?1 and that recorded for Zn was 0.011 and 0.022?mg?L?1, respectively. Among the two metals studied, toxicity of Zn was found to be greater to P. monodon than Pb. The activities of antioxidant defense enzymes and total protein content differed significantly from control following exposure to both metals. Overall, the biomarker studies demonstrated that alterations in antioxidant enzymes and induction of LPO reflect the consequences of heavy metal exposure in P. monodon.  相似文献   
86.
Survival of Mesorhizobium ciceri (SP4) and Azotobacter chroococcum (CBD-15 and M4) was tested on chickpea (Cicer arietinum) seeds treated with fungicides bavistin [methyl N-(1H-benzimidazol-2yl) carbamate] and thiram (tetramethyl-thiuram disulfide), whereas survival of phosphate solubilizing bacteria (PSB), Pseudomonas striata (27) and Bacillus polymyxa (H5) was examined on two cultivars (Arkel and BV) of pea (Pisum sativum) seeds treated with thiram. Viability of Azotobacter chroococcum (W5) was also examined on wheat (Triticum aestivum) seeds treated with bavistin, captan (cis-N-trichloromethyl thio-4 cyclohexane-1, 2-dicarboximide) and thiram under laboratory conditions using standard dilution and the plate count technique. All the tested strains of diazotrophs and PSB showed decline in their viable population on prolonged contact with fungicides. However, PSB showed variation in their viable population even with the cultivar.

BV cultivar of pea seeds showed better recovery of viable P. striata (10.75 to 10.61 log no. of viable cells with in 0-24 hrs) in the presence of thiram, whereas the Arkel cultivar of pea resulted in better recovery of viable B. polymyxa. Azotobacter chroococcum (W5), a potential strain for wheat, showed better survival in the presence of bavistin, compared to thiram and captan. Higher viable population of Mesorhizobium ciceri (SP4) and Azotobacter chroococcum (M4) was recovered from chickpea seeds treated with bavistin compared to thiram. However, thiram-treated seeds resulted in a greater number of extractable Azotobacter chroococcum (CBD-15). Under field conditions, adverse effect of thiram was reflected on the performance of Mesorhizobium ciceri (SP4) and A. chroococcum (M4) strains, resulting in reduced root and shoot biomass and grain yield, compared to bavistin treated and culture inoculated treatment. CBD-15 showed better performance in the presence of thiram compared to bavistin.  相似文献   
87.
Radon concentration was measured in water samples of 41 different locations from Udhampur district of Jammu & Kashmir, India, by using RAD7 and Smart RnDuo monitor. The variation of radon concentration in water ranged from 1.44 ± 0.31 to 63.64 ± 2.88 Bq L?1, with a mean value of 28.73 Bq L?1 using RAD7 and 0.64 ± 0.28 to 52.65 ± 2.50 Bq L?1, with a mean value of 20.30 Bq L?1 using Smart RnDuo monitor, respectively. About 17.07% of the studied water samples recorded to display elevated radon concentration above the reference range suggested by United Nation Scientific Committee on the Effects of Atomic Radiations (UNSCEAR). The mean annual effective dose of these samples was determined, and 78.95% samples were found to be within the safe limits set by World Health Organisation (WHO) and European Council (EU). The study revealed good agreement between the values obtained with two methods. Heavy metals (Zn, Cd, Fe, Cu, Ni, As, Hg, Co, Pb and Cr) were determined in water samples by microwave plasma atomic emission spectrometer, and their correlation with radon content was also analysed.  相似文献   
88.
The control and prevention of nutrient pollution from fish farming plays an essential role in the French regulatory framework. Assessing nutrient emissions from fish farms is important in terms of farm authorization, taxation, and monitoring. Currently employed strategies involve both water sampling and empirical modeling. This article reports the work and outcomes of an expert panel that evaluated existing methodologies and their possible alternatives. The development and evaluation of a nutrient-balance approach was assessed as a potential alternative to currently used methodologies. A previously described nutrient-balance model was suggested and parameterized using expert choice, and its validity and applicability were assessed. The results stress that the nutrient-balance model provides more robust and relatively conservative waste estimates compared to the currently used methodologies. Sensitivity of the approach to the uneven data quality available at farm level, difficulties of on-farm measurements, as well as model requirements and limitations are discussed.  相似文献   
89.
了解与水产饲料有关的环境负荷是评价和改进水产养殖环境性能的一项重要内容.本研究的目的是利用寿命周期评估(LCA)评价与法国用于硬头鳟生产的饲料有关的环境影响.所评价的各个阶段为:原材料的提取,所使用的原始配料的生产与改造,饲料的生产,饲料在养殖场的使用,各个阶段的运输以及能源的生产和使用.评价结果显示,渔业资源的利用(例如生物资源利用)以及养殖场中营养物的排放(例如富营养化潜能)对鲑科鱼饲料的潜在环境影响所起作用最大.改进饲料的组成以及管理做法看来是改善水产饲料环境概貌的最佳途径.  相似文献   
90.
Simultaneous overabundance and scarcity of inorganic phosphate(P_i) is a critical issue driving the development of innovative water/wastewater treatment technologies that not only facilitate Pi removal to prevent eutrophication,but also recover P_i for agricultural reuse.Here,a cell-surface expressed high-affinity phosphate binding protein(PstS) system was developed,and its P_i capture and release potential was evaluated.E.coli was genetically modified to express PstS on its outer membrane using the ice nucleation protein(INP)as an anchoring motif.Verification of protein expression and localization were performed utilizing SDS-polyacrylamide gel electrophoresis(SDS-PAGE),western blot,and outer membrane separation analyses.Cell surface characterization was investigated through acid-base titration,X-ray photoelectron spectroscopy(XPS),and Fourier transform infrared spectroscopy(FTIR).These tests provided information on the macromolecular structure and composition of the bacteria surface as well as the proton-exchange properties of the surface functional groups(i.e.,pKa values).Phosphate desorption and adsorption batch experiments were conducted to evaluate the effects of temperature,pH,and ionic strength on phosphate capture and release.The PstS surface-displayed cells demonstrated greater potential to release and capture phosphate compared to non-modified cells.Higher temperatures up to 40℃,basic pH conditions(pH=10.5),and higher ionic strength up to 1.0 mol/L KCl promoted 20%-50% higher phosphate release.  相似文献   
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