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291.
Environmental Science and Pollution Research - Several strains of Escherichia coli harbor virulence traits, resulting in E. coli–related intestinal and extra-intestinal infections. Various...  相似文献   
292.
This study aimed to assess the impacts of climate change on residential energy consumption in Dhaka city of Bangladesh. The monthly electricity consumption data for the period 2011–2014 and long-term climate variables namely monthly rainfall and temperature records (1961–2010) were used in the study. An ensemble of six global circulation models (GCMs) of coupled model intercomparison project phase 5 (CMIP5) namely, BCCCSM1-1, CanESM2, MIROC5, MIROC-ESM, MIROC-ESM-CHEM, and NorESM1-M under four representative concentration pathway (RCP) scenarios were used to project future changes in rainfall and temperature. The regression models describing the relationship between historical energy consumption and climate variables were developed to project future changes in energy consumptions. The results revealed that daily energy consumption in Dhaka city increases in the range of 6.46–11.97 and 2.37–6.25 MkWh at 95% level of confidence for every increase of temperature by 1 °C and daily average rainfall by 1 mm, respectively. This study concluded that daily total residential energy demand and peak demand in Dhaka city can increase up to 5.9–15.6 and 5.1–16.7%, respectively, by the end of this century under different climate change scenarios.  相似文献   
293.
294.
The crop pattern has a significant impact on the feasibility of sustainable agricultural practices. Selected crop pattern influences environmental and economic condition and affects sustainability profoundly in agricultural practices. Hence, a careful intervention is required in the selection of an optimal crop pattern for sustainable agricultural practices. Selection of a particular set of crop pattern depends on many criteria that may vary from place to place thus pose challenges in deciding an optimum crop pattern. The present research focuses on the crop selection pattern in Indian environment that considers comprehensive criteria related to sustainable farming practices. Based on the in-depth review of the literature and experts opinion, comprehensive criteria related to sustainable farming practices for Ravi season crop are identified. Total twelve criteria covering socioeconomic conditions, soil and water conditions, environmental and climatic conditions are earmarked and taken into account for eight most commonly grown crops in Ravi season and later on modeled to determine the crop pattern for most needed sustainability. A fuzzy-based multi-criteria decision-making model has been developed considering the Indian farming system. The scarce resources availability to Indian farmers poses many challenges to practice farming with most needed sustainability. The present research will be useful in the area of Indian farming practices in particular and global farming practices in general. It will also help stakeholders in their cost effective decision making for better crop productivity leading to sustainable farming practices. Additionally, the state policy makers will be able to formulate effective state driven sustainable farming policy to enhance its stake in gross domestic product to become self-reliance.  相似文献   
295.
The present study was conducted to determine the physico-chemical properties and heavy metal contents in soils under three land uses (agricultural, riverbank and roadside) from areas situated around rivers (Beas and Sutlej) in Punjab, India. Heavy metal contents in wheat samples (grain and fodder) growing in the area were also analyzed in order to find out potential human health risk through wheat consumption. The studied soils under the three land uses were found to be basic in nature with sandy texture, low soil organic matter and other soil nutrients. Comparatively higher amounts of soil nutrients were observed in soils under agricultural land use as compared to riverbank and roadside land uses. The amounts of heavy metals (Cr, Cu, Co and Pb) analyzed in soils were lower than the various national and international maximum permissible limits, but heavy metal contents observed in wheat fodder samples exceeded the maximum permissible limits for fodder. The soil-to-plant metal bioaccumulation factor was found to be highest for Cu (3.812 for soil–wheat grain and 1.874 for soil–wheat fodder), which showed the bioaccumulation of heavy metals from soils to crops, and the wheat straw-to-grain translocation factor was found to be highest for Co (4.375). The hazard index calculated to assess non-carcinogenic health risks was found above 1 for children, meaning that the wheat grains can pose health risks to children.  相似文献   
296.
Environmental Science and Pollution Research - The study was intended to investigate heavy metal contamination levels in the rice grown in the vicinity of the mining areas of Singhbhum Copper Belt,...  相似文献   
297.
Improperly managed organic waste constitutes a serious environment threat across the globe. This has led to a worldwide struggle to strike a balance between the rapid generation of such wastes and protection of the environment. With the unique advantages of lower operational and maintenance costs compared with other waste management technologies, the use of vermicomposting to manage organic wastes has been increasing rapidly in recent years. Still, some factors (e.g., characteristics of substrate composition before and after treatment) are in need of additional, specific studies so that researchers can better understand the metabolism involved in the process. Vermicomposting provides employment opportunities as it protects the environment, augmenting crop productivity when it is used as a fertilizer supplement and helping to maintain ecological balance. Thus, vermicompost plays an important role in the circular economy. This article provides an overview of the research activities that have been conducted on the use of vermicomposts to remove pollutants from the soil, in wastewater treatment, and in organic waste recycling throughout the world. Circular economic assessment has revealed that vermicomposting technology is usually feasible except in certain cases. Most other methods of waste disposal lead to soil deterioration, toxic effects, and increased pollution affecting land, air, water, and living beings, in addition to the sometimes considerable expense of their implementation. Thus, an eco‐friendly method that removes waste in one step is needed. Determining the long‐term performance and sustainable operation of vermicomposting systems still poses a challenge, however, as treatment performance is affected by design parameters, operational conditions, and environmental factors. This article summarizes the factors influencing pollutant removal through the vermicomposting process. Finally, this article highlights additional research that should be conducted on these issues to improve the performance of vermicomposting.  相似文献   
298.
Prevailing scenario of non-biodegradable food packaging materials worldwide was the motivation for this research. More than half of the packaging materials used today are non-biodegradable and lack one or the other feature that keeps it from being an ideal food packaging material. Based on the current need of food grade packaging materials, the present study illustrates the amelioration of the properties of biodegradable chitosan films with the incorporation of zinc oxide (ZnO) nanoparticles in varying concentration. The ZnO nanoparticles (ZnONPs) used as fillers in the chitosan films were synthesized by supersaturation method. They were characterized using UV–visible spectrophotometry, X-ray diffraction and field emission scanning electron microscopy (FE-SEM). The particles were observed to be around 100–200 nm in size. The chitosan films with varying concentration of ZnONPs were synthesized and characterized using Fourier transform infrared spectroscopy and FE-SEM. The films were studied for their thermal stability, water vapor transmission rate (WVTR) and mechanical properties. The thermal stability, as determined by Thermo Gravimetric Analysis and Differential Scanning Calorimetry increased slightly with increasing percentage of embedded ZnONPs while a substantial decrease in WVTR was observed. Mechanical properties also showed improvements with 77% increment in tensile modulus and 67% increment in tensile strength. The antimicrobial activity of the films was also studied on gram positive bacterium Bacillus subtilis (B. subtilis) and gram negative bacterium Escherichia coli (E. coli) by serial dilution method. A twofold and 1.5-fold increment in the antimicrobial activity was observed for B. subtilis and E. coli, respectively, with increased ZnONPs concentration in the films from 0(w/w) to 2%(w/w). Films thus prepared can prove to be of immense potential in the near future for antimicrobial food packaging applications.  相似文献   
299.
The binary mixture of ethanolic extract of powder, hecogenin, tigogenin, seed powder and thymol with synergiats MGK-264 and piperony butoxide in a 1:5 ratio were used against the . It was observed that the toxic effect of these mixtures were time and dose dependent. The binary mixtures of plant molluscicides with synergist were more toxic with respect to the independent toxicity of these plant molluscicides. Maximum synergistic action (10 fold) of MGK-264 and piperonyl butoxide was observed with hecogenin.  相似文献   
300.
Environmental Science and Pollution Research - The effect of the flow and geometric parameters of a dimple-roughened absorber plate on the enactment of solar air collectors (SACs) with air-impinged...  相似文献   
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