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631.
ABSTRACT

Microgrids are the key for integrating renewable energy from different sources into smart grid, that is why power grid evolves into a combination of interconnected microgrids. In fact, future power grids are undergoing this groundbreaking change that will help meet the increasing demand of electric power and reduce carbon emission. In this sense we study in this paper, based on measured data, a real case of energy management in the area of Beja located in Tunisia. Indeed, we propose a model for the power exchange which proves the potential of applying game theory in the development of both real-time pricing and energy management mechanism for an open electricity market. We also introduce a hybrid genetic algorithm to compute the Nash Equilibrium. Results show that the proposed smart energy management can decrease the real cost of power up to 20%, to divide the energy transmission losses by a factor of two and to reduce the carbon emission in the area of Beja.  相似文献   
632.
An estimate of heavy metals emissions to the atmosphere due to the projected changes in the Brazilian energy generation fuel matrix is presented. Present use of fossil fuel combustion for energy production is projected to increase from the present 14.5% to 29.6% of the total energy generation in Brazil in 2005. Most of this increase will be based on coal- and natural-gas-burning plants. The changes will result in an increase of about 100% in the average emissions (in tons year−1) of As (9.4 to 17.7), Cr (7.0 to 16.6) and Hg (2.4 to 4.1), 50% of Cd (1.2 to 1.8), and 20% of Ni (101 to 123) and Pb (23.3 to 29.9). Although relatively small for most heavy metals when compared to other industrial sources, the changes in the energy matrix will be particularly important for Hg, reaching a maximum emission of 12 tons (t) year−1, representing 15% of the total emissions of Hg to the atmosphere in Brazil. The use of Brazilian coals and the location of most coal-burning plants in a relatively small region in the south of the country strongly suggest that monitoring programs should be implemented during the building of the new plants. At a regional level the expected increase in Hg emissions to the atmosphere due to coal burning in Brazil, although small relative to North America and Europe, will equal the total amount estimated for South and Central America.  相似文献   
633.
Modeling of air pollutant dispersion has been undertaken for emissions of sulfur dioxide (SO2) at the Mina Al-Fahal refinery in the Sultanate of Oman. The study was conducted during the period of November 1999 to October 2000. The Industrial Source Complex Short-Term (ISCST32) air pollution model was adopted to predict the ground level concentration of SO2 in and around the refinery. The modeling results were validated against measured data during the study period. The comparison, based on the monthly average measurements, showed that the model underestimates the observed SO2 concentrations. However, the predicted ground level concentrations of SO2 during the months of September, October, November, and June were in better agreement with the observations. The predicted SO2 values are presented in the form of concentration contours to determine the spatial distribution of SO2 and to assess the impact on air quality over the survey area. Predicted SO2 concentrations were found lower than the World Health Organisation (WHO) guideline value of 365 μg/m3, with the maximum ground level concentrations being found to occur relatively close to the sources of emission. Moreover, concentration contour patterns for the modeled area vary with changes in meteorological conditions. On the basis of this study, the refinery is not likely to cause any significant deterioration in air quality, and predicted concentrations of SO2 are well below those likely to influence health.  相似文献   
634.
This paper considers how regional greenhouse gas emissioninventories can be determined. It presents a greenhousegas emissions inventory, by source, for the East Midlandsthat has been compiled as part of a regional study intoclimate change impacts in the United Kingdom. This hasused available local data, and national emissions datawith appropriate scaling factors. Total greenhouse gasemissions for the region are estimated to be 59 milliontonnes of carbon dioxide equivalent (CO2 equivalent)for 1997. Of these emissions, approximately 86% werecarbon dioxide emissions, 7% methane emissions, and 5%were nitrous oxide, with emissions of hydrofluorocarbons(HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride(SF6) contributing less than 2% of total emissions.  相似文献   
635.
Global warming is a result of increasing anthropogenic CO2 emissions, and the consequences will be dramatic climate changes if no action is taken. One of the main global challenges in the years to come is therefore to reduce the CO2 emissions.Increasing energy efficiency and a transition to renewable energy as the major energy source can reduce CO2 emissions, but such measures can only lead to significant emission reductions in the long-term. Carbon capture and storage (CCS) is a promising technological option for reducing CO2 emissions on a shorter time scale.A model to calculate the CO2 capture potential has been developed, and it is estimated that 25 billion tonnes CO2 can be captured and stored within the EU by 2050. Globally, 236 billion tonnes CO2 can be captured and stored by 2050. The calculations indicate that wide implementation of CCS can reduce CO2 emissions by 54% in the EU and 33% globally in 2050 compared to emission levels today.Such a reduction in emissions is not sufficient to stabilize the climate. Therefore, the strategy to achieve the necessary CO2 emissions reductions must be a combination of (1) increasing energy efficiency, (2) switching from fossil fuel to renewable energy sources, and (3) wide implementation of CCS.  相似文献   
636.
Environmental or ‘ecological’ footprints have been widely used in recent years as indicators of resource consumption and waste absorption on the basis of biologically productive land area required per capita with prevailing technology. Such footprints represent a partial measure of the extent to which the planet, its regions, or nations are moving along a sustainable development pathway. They vary between countries at different stages of economic development and varying geographic characteristics. The determinants of environmental footprints in some 113 countries from around the world have been evaluated. Dimensional analysis techniques from engineering and the physical sciences are employed to determine the relative significance of population density, economic wealth, and intensity of pollutant emission. Variations about the resulting ‘power‐law’ correlation suggest the extent to which individual nations are currently frugal or profligate in terms of their resource use and environmental impacts. The scatter associated with footprints, or closely related parameters, also indicates the uncertainty inherent within the international datasets needed to compute them, as well as differences in local climate and terrain. Nevertheless, national footprints alert humanity to the necessity of living within the regenerative capacity of the biosphere in order to ensure ‘environmental sustainability’.  相似文献   
637.
More and more countries are incorporating the instrument of emissions trading into their national climate policies. This emerging mosaic of emissions trading schemes (ETS) raises the question of whether they should be linked with each other. From an economic point of view, linking of domestic schemes is supposed to increase the economic efficiency of carbon markets. In addition, linking is also expected by some to yield substantial political benefits in terms of the evolution of the UNFCCC/Kyoto regime. However, these optimistic prospects are based on a best-case scenario where all major countries establish environmentally effective emissions trading systems and then link them with each other. Real-life politics might develop rather differently. This paper therefore examines to what extent the current status of emissions trading in industrialised countries provides a basis for reinforcing and moving forward the international climate regime through linking domestic ETS. After comparing emerging emissions trading schemes from an institutional perspective, it emerges that not only emissions trading is at a very early stage in most countries, in addition the emerging systems are probably going to be designed very differently from the EU ETS. While for some design features such as the coverage design differences do not matter, there are some areas where the plans in many non-EU countries look crucially different from the EU system. The outlook for a linked international ETS is therefore currently still very uncertain. Given this state of affairs, the EU should pro-actively engage with the non-EU countries to try to harmonise their developing national emissions trading schemes with the EU ETS, widely disseminate the lessons it has learned from the EU ETS, strongly make the case for environmental integrity and at the same time make clear that systems that want to link to the EU ETS will need to meet certain quality criteria.
Ralf SchüleEmail:
  相似文献   
638.
The main purpose of industrial ecology is to evaluate and minimize impacts from economic activities of human society. Tourism as one economic activity, results in a full range of environmental impacts, but few applications of industrial ecology to tourism management have previously been discussed. Life cycle assessment (LCA) is used in this research to explore environmental impacts of island tourism, and then the environmental loads per tourist per trip can be found. Penghu Island in Taiwan is taken as an example to examine this new approach. Various environmental loads in transportation, accommodation, and recreation activity sector are all inventoried and calculated here. In summary, per tourist per trip uses 1606 MJ of energy, 607 L of water, and emits 109,034 g of CO2, 2660 g of CO, 597 g of HC, 70 g of NOx. In addition, per tourist per trip also discharges 416 L of wastewater, 83.1 g of BOD, and 1.95 g of solid waste. In terms of energy use, the transportation consumes the largest energy (67%); in particular, the airplane sector. Moreover, per Penghu tourist results in more environmental loads than local people; for example, the amount of solid waste discharge per tourist is 1.95 kg per day, while that of per local people is 1.18 kg. Finally, the advantages and limitations of such LCA approach are also discussed.  相似文献   
639.
半导体制造业作为信息产业的基础,半导体元件的需求增长迅速。半导体行业的环保节能研究已成为技术发展的主题。全氟化碳(PFCS)为目前认为具有高温室气体暖化潜势的气体,也是《京都议定书》控制的6种温室气体之一,对气候的影响能力不可忽视。全球各半导体行业、环保部门及相关研究机构仍在不断努力减排。本文从半导体行业中PFCS的排放现状、产污环节、排放特点、污控途径、激励措施等方面对其减排途径进行了研究和分析。  相似文献   
640.
将能源结构指标Es引入到IGT模型中,并用模糊矩阵对Es进行计算,同时,采用马尔可夫模型对湖南省能源结构进行预测,结果显示:到2020年,湖南省煤、石油、天然气、水电在一次能源消费中的占比为:54.75%:10.75%:2.75%:26.24%;在此能源结构的基础上,用基于能源结构的IGT模型对湖南省CO2排放量进行预测,预测结果显示:2020年湖南省CO2排放量为48 787.23万吨,是2010年的1.51倍,但其单位GDP的CO2排放量仅为1.19吨/万元,比2010年下降41.6%;2020年因能源结构优化而减排的CO2量为7 049.79万吨,占当年CO2排放总量的14.45%。此外,当湖南省单位GDP年均节能率达到7.8%左右时,其CO2排放量将维持2010年的水平不变,从而实现经济增长和CO2排放量的脱钩。  相似文献   
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