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121.
In this communication, experiments have been performed to check the capability of the newly formed composite desiccant material (CaCl2/floral) for the extraction of freshwater from atmospheric air. Three numbers of solar glass desiccant box type system (SGDBS) with a captured area of 0.36 m2 each, have been used. The design parameters for the water production are height of glass from desiccant bed at 0.22 m, inclination in angle as 30°, the effective thickness of glass as 3 mm and number of glazing as single. The maximum yield by the new composite desiccant material is 0.35 ml/cm3/day. The efficiency of the system SGDBS with 37 % concentration of CaCl2 is 76.44 %.  相似文献   
122.
The present study was aimed to characterize physico-chemical and microbial population of distillery effluent and isolate a novel thermotolerant bacterium for color, COD, and BOD reduction of spentwash. The level of alkalinity, TSS, DO, COD, BOD, TN, ammonical nitrogen, nitrate nitrogen, phosphorous, potassium, chloride, and calcium of spentwash (SW), bioreactor effluent (BE), and secondary treated effluent (STE) were well above the permissible limits. The level of color, TS, and TDS were under the permissible limits for STE but not for SW and BE. The microbial population was higher in BE. The results revealed that effluent was highly polluted and require suitable treatment before discharge. A novel thermotolerant bacterium, identified as Pediococcus acidilactici, was isolated which exhibited maximum 79 % decolorization, 85 % COD, and 94 % BOD reduction at 45 °C using 0.1 %, glucose; 0.1 %, peptone; 0.05 %, MgSO4; 0.05 %, K2HPO4; pH 6.0 within 24 h under static condition. The ability of this strain to decolorize melanoidin at minimum carbon and nitrogen supplementation warrants its possible application for effluent treatment at industrial level. In addition, it is first instance when melanoidin decolorization was reported by P. acidilactici. This study could be an approach towards control of environmental pollution and health hazards of people in and around the effluent distillery unit.  相似文献   
123.
Abstract

A time series approach using autoregressive integrated moving average (ARIMA) modeling has been used in this study to obtain maximum daily surface ozone (O3) concentration forecasts. The order of the fitted ARIMA model is found to be (1,0,1) for the surface O3 data collected at the airport in Brunei Darussalam during the period July 1998-March 1999. The model forecasts of one-day-ahead maximum O3 concentrations have been found to be reasonably close to the observed concentrations. The model performance has been evaluated on the basis of certain commonly used statistical measures. The overall model performance is found to be quite satisfactory as indicated by the values of Fractional Bias, Normalized Mean Square Error, and Mean Absolute Percentage Error as 0.025, 0.02, and 13.14% respectively.  相似文献   
124.
Aim of the present study is to determine the in-vitro cell cytotoxic effect of native and transformed cancer drugs (cyclophosphamide and etoposide) using three different white rot fungi (Ganoderma lucidum, Phanerochaete chrysosporium and Trametes versicolor). At 3, 6, 9, 12 and 15 days, experiments were done on a mouse monocyte macrophage cell line (Raw 264.7). After biodegradation, the altered compounds were found to be harmful to the Raw 264.7 cells. The maximal cytotoxicity of cyclophosphamide transformed products (TPs) were determined to be 2.4%, 7.3% and 7% respectively, against G. lucidum, P. chrysosporium and T. versicolor, respectively. With G. lucidum, P. chrysosporium and T. versicolor, the etoposide toxicity was 1.5%, 8% and 2.7% respectively. P. chrysosporium-mediated biodegradation resulted in the maximum toxicity, at 8%, on the 12th day for etoposide and 7.3% on the 3rd day for cyclophosphamide. After biodegradation by fungi, the toxicity of these two anticancer agents was reduced in the form of metabolites, but each fungus showed unique capacity for toxicity removal.  相似文献   
125.
Considering the mounting evidences of the effects of air pollution on health, the present study was undertaken to assess the ambient air quality status in the fast growing urban centres of Haryana state, India. The samples were collected for total suspended particulate matter (TSPM), respirable suspended particulate matter (PM10), sulfur dioxide (SO2), and oxides of nitrogen (NO2) during different seasons from 8 districts of Haryana during January, 1999 to September, 2000. The four types of sampling sites with different anthropogenic activities i.e. residential, sensitive, commercial and industrial were identified in each city. The ambient air concentration of TSPM and PM10 observed was well above the prescribed standards at almost all the sites. The average ambient air concentrations of SO2 and NO2 were found below the permissible limits at all the centres. Comparatively higher concentration of SO2 was observed during winter seasons, which seems to be related with the enhanced combustion of fuel for space heating and relatively stable atmospheric conditions. Air Quality Index (AQI) prepared for these cities shows that residential, sensitive and commercial areas were moderately to severely polluted which is a cause of concern for the residents of these cities. The high levels of TSPM and SO2 especially in winter are of major health concern because of their synergistic action. The data from Hisar city reveals a significant increase in the total number of hospital visits/admissions of the patients with acute respiratory diseases during winter season when the level of air pollutants was high.  相似文献   
126.
127.
Bacterial strains with poly-3-hydroxybutyrate (PHB) degradation potential were isolated from waste yard soil samples of selected industrial sites in Uttarakhand, India, and two microbial consortia were developed, i.e. Consortium I comprises Pseudomonas sp. strain Rb10, Pseudomonas sp. strain Rb11 and Bacillus sp. strain Rb18, and Consortium II is composed of Lysinibacillus sp. strain Rb1, Pseudomonas sp. strain Rb13 and Pseudomonas sp. strain Rb19. The current study involved enrichment selection via liquid and semi-solid media, followed by isolation and screening of bacterial strains using PHB pellets and films. Furthermore, the identification and characterisation was done by triphasic approach. The utilisation of PHB by the characterised strains was confirmed by Fourier transform infrared spectroscopy and scanning electron microscopy. Moreover, the minimum inhibitory concentration of solubilised PHB was found to be 2.5?mg/mL, which was detected through ‘clear zone assay’. Further, the selection and biocompatibility testing of potential isolates were performed for the formation of bacterial consortia. Thus, the present work would provide direct and standardised protocol for screening and selection of potential microbiomes for biodegradation of polymers by overcoming the negative effect of organic solvents. Moreover, indigenously developed consortia would be evaluated for their in situ biodegradation potential against various bioplastic films.  相似文献   
128.
The present work deals with the determination of uranium concentrations in drinking and ground water samples by laser fluorimetry and calculation of cumulative, age-dependent radiation doses to humans. The concentrations were found to be between 0.20 ± 0.03 and 64.0 ± 3.6 μg L?1, with an average of 11.1 ± 1.5 μg L?1, well within the drinking water limit of regulatory bodies. The concentrations of uranium increase with depth of water samples collection. The estimated annual ingestion dose due to the intake of uranium through drinking water for all age groups varied between 0.2 and 137 μSv a?1, with an average of 17.3 μSv a?1. The mean annual ingestion dose is 5% of the global average ingestion dose, for infants, marginally higher than for other age group. Most effective dose values were less than 20 μSv a?1.  相似文献   
129.
The effect of antioxidant rich diet supplements of Spirulina and tamarind fruit pulp at 230 mg kg?1 body weight, separately as well as in combination, on various hematological parameters of Swiss albino mice exposed to fluoride for seven days at daily doses of 190 mg kg?1 body weight and for 90 days at daily doses of 94 mg kg?1 body weight is reported. Compared with controls, fluoride exposure decreased erythrocyte (12%–18%), leukocyte (16%) and platelet counts (7%, only for short-term exposure), hemoglobin (2%–17%) and packed cell volume (2%–14%) in Swiss albino mice reared on standard feed but these were altered little in the diet supplement groups. Fluoride exposure decreased lymphocytes in both standard feed (16%–21%) and diet supplement groups (5%–19%, but only after long-term exposure). Fluoride withdrawal led to recovery of the post-treated mice from long-term exposure. Spirulina alone and also in combination with tamarind fruit pulp was found more effective than tamarind alone in reducing hematological disorders in fluoride treated mice.  相似文献   
130.
Environmental Chemistry Letters - Microbial fuel cells are used as an alternative source of energy and for microbial degradation of waste and pollutants. Different types of microbial fuel cells...  相似文献   
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