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131.
The aim of this study was to investigate the effects of curcumin (CUR) on antioxidant status, body weight (BW) gains, and some reproductive parameters in male rats exposed to subchronic doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Thirty-two rats were divided into four groups. The first group was kept as control. The second group (TCDD group) was given TCDD at a dose of 50 ng·kg?1 BW per day; the third group (CUR group) was treated with CUR at a dose of 80 mg·kg?1 BW per day. The fourth group (TCDD + CUR group) was given TCDD and CUR at the same doses simultaneously. Malondialdehyde (MDA) levels were significantly increased in the TCDD group. In addition, TCDD exposure decreased liver superoxide dismutase (SOD) activity, catalase (CAT) activities of kidney and brain, glutathione peroxidase (GSH-Px) activities of liver, kidney, and brain, and glutathione levels of liver, kidney, and heart. However, CUR treatment with TCDD exposure decreased MDA levels in all tissues and increased SOD activities of liver, kidney, and brain, CAT activity of heart, and GSH-Px activities of heart and brain. TCDD caused a decrease in BW gain, and CUR partially eliminated this effect of TCDD. In addition, while reproductive organ weights, sperm concentration, and sperm motility tended to decrease with TCDD exposure, these effects tended to be close to normal levels by CUR treatment. In conclusion, CUR was seen to be effective in the treatment and prevention of toxicity induced by subchronic TCDD exposure.  相似文献   
132.
Profenofos and trizaophos (organophosphates) carbofuran and carbaryl (carbamates) are among the major toxicants polluting freshwater bodies, as well as exerting a significant effect on the health of fish. In this study, the 96 h LC50 of the most commonly used organophosphates and carbamates was determined in one of the indigenous fish species, Labeo rohita fingerlings. Pesticides were applied to fingerlings that had been grown under optimized standard conditions under a maintained static bioassay system. Probit analysis was used for the determination of LC50 values, which were ascertained as 6.64, 0.32, 1.4, and 8.24 mg/L for triazophos, profenofos, carbofuran, and carbaryl, respectively. Acute toxic stress was noted with fish exhibiting behavioral toxicity including suffocation, lying on the bottom, erratic swimming, lethargy and downward movements, and gulping prior to mortality.  相似文献   
133.
Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants that are mutagenic, carcinogenic, and toxic to living organisms. Here, the ability and effectiveness of selected bacteria isolated from an oil‐contaminated area in biodegrading PAHs were evaluated, and the optimal conditions conducive to bacterial PAH biodegradation were determined. Of six bacterial isolates identified based on their 16S rRNA sequences, Planomicrobium alkanoclasticum could subsist on and consume nearly all hydrocarbons according to the 2,6‐dichlorophenolindophenol assay. The efficacy of this isolate at PAH biodegradation was then empirically confirmed. After 30 days of incubation, P. alkanoclasticum degraded 90.8% of the 16 PAH compounds analyzed and fully degraded eight of them. The optimum P. alkanoclasticum growth conditions were 35°C, pH 7.5, and NaNO3 as the nitrogen source. Under these biostimulant conditions, P. alkanoclasticum degraded 91.4% of the total PAH concentration and completely decomposed seven PAHs after 15 days incubation. Hence, P. alkanoclasticum is an apt candidate for the biodegradation of PAHs and the bioremediation of sites contaminated by them.  相似文献   
134.
Journal of Material Cycles and Waste Management - Hazardous waste management (HWM) in chemical industrial parks is an important issue related to sustainable development. Previous researches...  相似文献   
135.
136.
Ozonation of alpha endosulfan and the effects of some parameters such as pH, temperature and partial pressure on ozonation were investigated and the kinetic constants were calculated in this study. Alpha endosulfan solutions were ozonated in a lab-scale semi-batch reactor under variable experimental conditions. Increase in dissolved ozone concentration had a positive effect on oxidation rate. Alpha endosulfan could be removed up to 94% at pH 4 for an ozonation time of 60 minutes. The oxidation reaction was found to be of second order and of first order with respect to both ozone and alpha endosulfan. The temperature dependent reaction expression of alpha endosulfan was obtained as kd = (1.889 exp(- 2.21 x 10(-3)/T). It was concluded that, although the rate of reaction was lower than the rate of other pesticide oxidation reported in the literature. alpha endosulfan presented an obvious reaction to ozonation.  相似文献   
137.
ABSTRACT: Irrigation has expanded in parts of the eastern United States. In some areas, the adjoining surface (riparian) water is the most economical source of irrigation water. Expanded demand for riparian water may lead to conflict among irrigators and other streamflow users. Accurate information on the potential for and impacts of riparian irrigation expansion is needed to decide if control of such expansion is necessary. In this study, a stochastic economic model to evaluate the impacts of potential irrigation expansion is presented. The model considers the soil, location, and land use characteristics of individual sites, as well as weather and streamflow patterns. The application of the model to an eastern Virginia watershed indicates that, with maximum potential expansion, water availability becomes limited and yields will be reduced in some years. As a result, the expected net returns from irrigation and the probability of breaking even on the investment are reduced substantially. The results suggest the need to consider regulation of surface water allocation for irrigation development in riparian watersheds.  相似文献   
138.
Environmental Science and Pollution Research - The present study aims at evaluating the batch scale potential of cotton shell powder (CSP), Moringa oleifera leaves (ML), and magnetite-assisted...  相似文献   
139.
In this study, the influence of anthropogenic pollution on the aquatic environment of Plitvice Lakes National Park (PLNP) was investigated during 2011–2012 using a combination of chemical and cytogenetic analyses. Four groups of major contaminants [(volatile organic compounds: benzene, toluene, ethylbenzene, and xylenes (BTEX); persistent organochlorine pollutants: organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs); major and trace elements; anthropogenic radionuclides (90Sr, 134Cs, and 137Cs)] were determined in three aquatic compartments (water, sediment, fish). Mass fractions of inorganic constituents in different compartments reflected the geological background of the area, indicating their origin from predominantly natural sources. Levels of volatile and persistent organic compounds in water and fish, respectively, were very low, at levels typical for remote pristine areas. Analysis of anthropogenic radionuclides in water and sediment revealed elevated activity concentrations of 137Cs in water, and measurable 134Cs in the upper sediment layers from April 2011, possibly as a consequence of the Fukushima nuclear accident in March 2011. The potential genotoxicity of river and lake water and lake sediment was assessed under laboratory conditions using the alkaline comet assay on human peripheral blood lymphocytes, and measured levels of primary DNA damage were within acceptable boundaries. The results showed that despite the protected status of the park, anthropogenic impact exists in both its terrestrial and aquatic components. Although contaminant levels were low, further monitoring is recommended to make sure that they will not rise and cause potentially hazardous anthropogenic impacts.  相似文献   
140.
Proper management of healthcare wastes is a key concern across resource-constrained countries in South Asia. Existing scientific research on this topic usually involves epidemiological and behavioral studies. Similarly, environmental impact assessment of healthcare wastes is mainly conducted from an end-user or anthropocentric point of view. In this study, we took a novel approach by analyzing healthcare wastes using an ecocentric position. Here, we utilize a case study of a general public hospital in a major city of Pakistan to analyze the embodied energy of its waste fractions by category. We used Emergy analysis to assess the true economic potential of recycling these waste items. While doing so, we compared the economic potential of current waste recycling practices with the scenario of 100% recycling of useful waste fractions. We discovered that the latent embodied energy of different recyclable waste fractions made them far more valuable than their existing market prices indicate. This value increased further if the useful waste fractions were completely recycled. In conclusion, this study used empirical evidence to argue in favor of source-segregation and recycling of healthcare wastes so that the higher costs associated with natural resource extraction and processing can be avoided. Future studies considering hazardous healthcare wastes can use the approach taken in this paper to analyze the impact of other practical waste treatment procedures.  相似文献   
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