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121.
Data from two cross-sectional surveys totaling over 2000 farmers in Pakistan are analyzed with regression techniques to estimate the value productivity of irrigation water and related resources. Returns to irrigation water vary by province, but in general are found to be high relative to estimated costs of obtaining water. Salinity of water supplies is an important productivity depressant. The results will be useful in determining the economic feasibility of various means for augmenting supplies and for improving delivery and application efficiencies.  相似文献   
122.
Environmental Science and Pollution Research - This study aims to evaluate the environmental performance of small and medium-sized enterprises (SMEs) through green human resource...  相似文献   
123.
Environmental Science and Pollution Research - Advancements in the design and technology of constructed wetlands for efficient removal of wastewater contaminants are ever in progress to develop...  相似文献   
124.
The accumulation of dust pollution on the photovoltaic (PV) module can have a significant effect on the productivity and efficiency of PV systems in different locations in the world. Dust which accumulated over time on the PV module and is based on weather conditions led to the reduction in the effectiveness of solar cells. The aim of this research was to experimentally investigate the effect of the natural dust and the effects of environmental parameters on PV performance. The experiments were conducted to propose a model for the current, voltage, power and efficiency and to simulate the effect of environmental parameters on PV performance. The natural dust investigated consisted of different compounds: SiO2 (45.53 %), CaO (24.62 %), Al2O3 (10.83 %), Fe2O3 (10.46 %), MgO (6.33 %), K2O (0.87 %), TiO2 (0.45 %), SO3 (0.24 %), MnO2 (0.21), Cr2O3 (0.23 %), SrO (0.13 %) and NiO (0.09 %). It was found that the most accurate correlation is a polynomial from seventh degree for current, voltage, power and efficiency, fourth degree for solar radiation and temperature, cubic degree for humidity and wind velocity. The coefficients of general model are 0.6343, 0.0110, 0.0 and 0.0001 for PV module, respectively, with 0.0011 fitting factor. The proposed model has been validated using models in the literature.  相似文献   
125.
We examine the causal relationship between globalisation and CO2 emissions for 25 developed economies in Asia, North America, Western Europe and Oceania using both time series and panel data techniques, spanning the annual data period of 1970–2014. Because of the presence of cross-sectional dependence in the panel, we employ Pesaran’s Journal of Applied Econometrics 22, 265–312 (2007) cross-sectional augmented panel unit root (CIPS) test to ascertain unit root properties. The Westerlund Oxford Bulletin of Economics and Statistics 69, 709–748 (2007) cointegration test is also used to ascertain the presence of a long-run association between globalisation and carbon emissions. The long-run heterogeneous panel elasticities are estimated using the Pesaran Econometrica, 74(4), 967–1012 (2006) common correlated effect mean group (CCEMG) estimator and the Eberhardt and Teal Productivity analysis in global manufacturing production (2010) augmented mean group (AMG) estimator. The causality between the variables is examined by employing the Dumitrescu and Hurlin Economic Modelling, 29, 1450–1460 (2012) and Emirmahmutoglu and Kose Economic Modelling, 28, 870–876 (2011) Granger causality tests. The empirical results reveal that globalisation increases carbon emissions, and thus, the globalisation-driven carbon emission hypothesis is valid. This empirical analysis suggests insightful policy guidelines for policy makers using ‘globalisation’ as an economic tool for better long-run environmental policy.  相似文献   
126.
A Burkard personal volumetric sampler was used at Sriniketan, a town about 150 km northwest of Calcutta, in the state of West Bengal, in eastern India to record the frequency of three common airborne Cassia pollen types, Cassia tora, Cassia occidentalis, and Cassia fistula for two consecutive years (2004–2006). Correlation was made between the meteorological factors and the pollen concentration in the atmosphere. The study reports Cassia pollinosis by in vivo skin prick test in respiratory allergic patients. The highest positive reactions were exhibited by C. tora (34.7 %), C. fistula (33.3 %), and C. occidentalis (28.5 %). The allergic potential of these was investigated by in vitro enzyme linked immunosorbent assay test. Their protein components were analyzed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis, in the range of 15.8–81.5 kDa. In C. occidentalis and C. fistula, 11 bands were found, while it was 10 in C. tora. The results show that the Cassia pollen occur significantly in the atmosphere with the potential to elicit an allergic response in susceptible patients.  相似文献   
127.
Manual closed chamber methods are widely used for CH4 measurement from rice paddies. Despite diurnal and seasonal variations in CH4 emissions, fixed sampling times, usually during the day, are used. Here, we monitored CH4 emission from rice paddies for one complete rice-growing season. Daytime CH4 emission increased from 0800 h, and maximal emission was observed at 1200 h. Daily averaged CH4 flux increased during plant growth or fertilizer application and decreased upon drainage of plants. CH4 measurement results were linearly interpolated and matched with the daily averaged CH4 emission calculated from the measured results. The time when daily averaged emission and the interpolated CH4 curve coincided during the daytime was largely invariant within each of the five distinctive periods. One-hourly sampling during each of these five periods was utilized to estimate the emission during each period, and we found that five one-hourly samples during the season accurately reflected the CH4 emission calculated based on all 136 hourly samples. This new sampling scheme is simple and more efficient than current sampling practices. Previously reported sampling schemes yielded estimates 9 to 32% higher than the measured CH4 emission, while our suggested scheme yielded an estimate that was only 5% different from that based on all 136-h samples. The sampling scheme proposed in this study can be used in rice paddy fields in Korea and extended worldwide to countries that use similar farming practices. This sampling scheme will help in producing more accurate global methane budget from rice paddy fields.  相似文献   
128.
青弋江流域不同级别河流底栖动物群落结构研究   总被引:2,自引:0,他引:2  
2013年8月对青弋江流域不同级别河流底栖动物进行了调查。共采集到底栖动物60种,隶属于39科58属。从1级到4级河流,种类数表现出逐渐减少的趋势,分别为46、39、36和16种。1~3级河流中种类数最多的均是水生昆虫,4级河流中种类数最多的是软体动物。整个流域底栖动物密度和生物量分别为382 ind./m2和3643 g/m2。不同级别河流中,2级河流底栖动物密度最大,4级河流密度最小,且二者存在显著差异;2级和4级河流底栖动物生物量都较高,且显著高于1级河流。在功能摄食类群方面,整个流域以刮食者和过滤收集者为主。随着河流级别的增加,刮食者相对密度和相对生物量表现出先增加后下降的趋势;撕食者在1、2级河流所占比例较高;直接收集者和过滤收集者在1级和4级河流中所占比例较高  相似文献   
129.
A beautiful and clean environment is the desire of every society. Malaysia is facing an uncontrolled increase in municipal solid waste (MSW) generation due to population growth, economic advancement, and industrialization, but the current, most common waste disposal practice of landfilling is not sustainable. The increasing standard of living also saps more energy from the power generation systems in which fossil fuels are the major source of fuel for the plants. Malaysia generates about 0.5–1.9 kg/capita/day of MSW; a total of about 25,000 tonnes/day of MSW is currently generated and is estimated to exceed 30,000 tonnes/day by 2020. Malaysian MSW is mainly composed of 45 % food waste, 24 % plastic, 7 % paper materials, 6 % metal, 4 % wood and 3 % glass, which are commingled, and is thus characterised by 52–66 % moisture content. Currently, 80–95 % of collected MSW is landfilled and 5 % is recycled, while composting and energy recovery are rarely practiced. This paper reviews the solid waste practice in Malaysia and looks into alternative management options for sustainability. Malaysia MSW represents recyclable power and energy potential if properly sorted. This study considered the practice of sorting at the source and the use of combustible MSW components as fuel to generate heat for a hybrid solar, flue gas, chimney power plant.  相似文献   
130.
Abstract

Adult and larval insects from the terrestrial and aquatic environments were exposed to acephate. The chemical was more toxic to adult insects than to larvae, and was a poor insect cholinesterase inhibitor in vitro compared to methamidophos which was a much stronger inhibitor. Both acephate and methamidophos inhibited the adult cholinesterase in vitro much more strongly than they did the larval enzymes. Acephate was metabolized by the insects to methamidophos which did not appear to be the only metabolite, although no other metabolites were looked for. The cholinesterase of insects exposed to sublethal levels of acephate was inhibited, but this inhibition appeared to be due to the combined effect of acephate and methamidophos and not to any hypothetical substance with greater anticholinesterase activity. This was bourne out when acephate was incubated with mixed function oxidases (MFO). No activated product with potent anticholinesterase activity was identified. Methamidophos was not produced by the MFO system but by some other unidentified mechanism.  相似文献   
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