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651.
In this paper the necessity for effective joint working arrangements between Environmental Health Officers and Transport Planners is demonstrated as a fundamental prerequisite for successful management of traffic-related air quality in English local government areas. Current approach to joint working and collaboration between the officers was examined based on the evidence from a three-year study which involved questionnaire surveys and case study interviews. The findings show that despite good administrative devolution and policy integration, the chance of improving specific local air quality situations through the Local Transport Planning process is dependent on other overriding factors which influence the capabilities of the authorities to integrate policies across departments and tiers of governments. Implicit in these findings is the need for a shared paradigm of continuous engagement by all the policy actors and stakeholders if proper integration and the possibility of tangible results in future policy development are to be achieved. The paper proposes a new framework through which such collaborations can be developed and within which solutions to the issues identified can be evaluated.  相似文献   
652.
● We evaluated the accuracy of iPhone data in capturing time-activity patterns. ● iPhone data captured the most important microenvironments and time spent in them. ● iPhone data also accurately captured daily exposure to ambient PM pollution. ● A considerable fraction of the population in the USA may have iPhone data available. ● iPhone data has great potential in air pollution health studies. In many air pollution health studies, the time-activity pattern of individuals is often ignored largely due to lack of data. However, a better understanding of this location-based information is expected to decrease uncertainties in exposure estimation. Here, we showcase the potential of iPhone’s Significant Location (iSL) data in capturing the user’s historical time-activity patterns in order to estimate exposure to ambient air pollutants. In this study, one subject carried an iPhone in tandem with a reference GPS tracking device for one month. The GPS device recorded locations in 10 second intervals while the iSL recorded the time spent in locations the subject visited frequently. Using GPS data as a reference, we then evaluated the accuracy of iSL data in capturing the subject’s time-activity patterns and time-weighted air pollution concentration within the study time period. We found the iSL data accurately captured the time the subject spent in 16 microenvironments (i.e. locations the subject visited more than once), which was 93% of the time during the study period. The average error of time-weighted aerosol optical depth value, a surrogate of particle pollution, is only 0.012%. To explore the availability of iSL data among iPhone users, an online survey was conducted. Among the 349 surveyed participants, 72% of them have iSL data available. Considering the popularity of iPhones, iSL data may be available for a significant portion of the general population. Our results suggest iSL data have great potential for characterizing historical time-activity patterns to improve air pollution exposure estimation.  相似文献   
653.
• The Large scale Urban Consumption of energY model was updated and coupled with WRF. • Anthropogenic heat emissions altered the precipitation and its spatial distribution. • A reasonable AHE scheme could improve the performance of simulated PM2.5. • AHE aggravated the O3 pollution in urban areas. Anthropogenic heat emissions (AHE) play an important role in modulating the atmospheric thermodynamic and kinetic properties within the urban planetary boundary layer, particularly in densely populated megacities like Beijing. In this study, we estimate the AHE by using a Large-scale Urban Consumption of energY (LUCY) model and further couple LUCY with a high-resolution regional chemical transport model to evaluate the impact of AHE on atmospheric environment in Beijing. In areas with high AHE, the 2-m temperature (T2) increased to varying degrees and showed distinct diurnal and seasonal variations with maxima in night and winter. The increase in 10-m wind speed (WS10) and planetary boundary layer height (PBLH) exhibited slight diurnal variations but showed significant seasonal variations. Further, the systematic continuous precipitation increased by 2.1 mm due to the increase in PBLH and water vapor in upper air. In contrast, the precipitation in local thermal convective showers increased little because of the limited water vapor. Meanwhile, the PM2.5 reduced in areas with high AHE because of the increase in WS10 and PBLH and continued to reduce as the pollution levels increased. In contrast, in areas where prevailing wind direction was opposite to that of thermal circulation caused by AHE, the WS10 reduced, leading to increased PM2.5. The changes of PM2.5 illustrated that a reasonable AHE scheme might be an effective means to improve the performance of PM2.5 simulation. Besides, high AHE aggravated the O3 pollution in urban areas due to the reduction in NOx.  相似文献   
654.
利用2015~2017年攀枝花市污染因子和气象要素实测数据,运用GIS技术、相关分析以及统计分析等方法,分析攀枝花市空气污染因子和气象要素的时空特征及相关性。结果表明:攀枝花市首要污染物为PM10,其次是NO2;秋冬以PM10和NO2污染为主,春夏PM10和O3为主。不同季节,各气象要素对本地空气质量的影响程度及空间分布存在明显差异。弄弄坪一带PM2.5和SO2、CO浓度偏高,市中心炳草岗一带PM10、O3和NO2浓度偏高。结合本地发展规划和实际情况,根据气象要素分析,为攀枝花市分区分季节的防污减排决策提供气象参考。  相似文献   
655.
Because of its large population and rapidly growing economy, China is confronting a serious energy shortage and daunting environmental problems. An increased use of fuels derived from biomass could relieve some demand for nonrenewable sources of energy while providing environmental benefits in terms of cleaner air and reduced emissions of greenhouse gases. In 2003, China generated about 25.9 × 108 metric tons of industrial waste (liquid + solid), 14.7 × 108 metric tons/year (t/y) of manure (livestock + human), 7.1 × 108 t/y of crop residues and food-processing byproducts, 2 × 108 t/y of fuelwood and wood manufacturing residues, and 1.5 × 108 t/y of municipal waste. Biofuels derived from these materials could potentially displace the use of about 4.12 × 108 t/y of coal and 3.75 × 106 t/y of petroleum. An increased bioenergy use of this magnitude would help to reduce the emissions of key air pollutants: SO2 by 11.6 × 106 t/y, NOX by 1.48 × 106 t/y, CO2 by 1.07 × 109 t/y, and CH4 by 50 × 106 t/y. The reduced SO2 emissions would be equivalent to 54% of the national emissions in 2003, whereas those for CO2 are 30%. It is important to recognize, however, that large increases in the use of biomass fuels also could result in socioeconomic and environmental problems such as less production of food and damage caused to natural habitats.  相似文献   
656.
Recent federal policy proposals to reduce emissions of sulfur dioxide (SO(2)), nitrogen oxides (NO(x)), and mercury from the US electricity sector promise important improvements in air quality and reductions in acid deposition. The cost of achieving these reductions depends on the form and stringency of the regulation. In this research, we analyze the economic benefits and costs of the US Environmental Protection Agency's (EPA's) Clean Air Interstate Rule (CAIR) as characterized in the supplemental rule proposed in June 2004, and the Clean Air Mercury Rule (CAMR) as proposed in February 2004. The assessment integrates a model of the electricity sector, two models of atmospheric transport of air pollutants, and a model of environmental and public health endpoints affected by pollution. We model explicitly the emissions of SO(2), NO(x), mercury and carbon dioxide (CO(2)) and the effects of changes in emissions of SO(2) and NO(x) on environmental and public health. The manner in which mercury emissions are regulated will have important implications not only for the cost of the regulation, but also for emission levels for SO(2) and NO(x) and where those emissions are located. We find the economic benefits of CAIR and CAMR are far greater than the costs. Recent estimates of benefits of reductions in mercury and acidification indicate that our model captures the lion's share of quantifiable benefits. We also find that the EPA would have been justified on economic grounds in pursuing additional SO(2) emissions reductions beyond the requirements of CAIR.  相似文献   
657.
Trees have been widely quoted as effective scavengers of both gaseous and particulate pollutants from the atmosphere. Recent work on the deposition of urban aerosols onto woodland allows the effect of tree planting strategies on airborne aerosol concentrations to be quantified and considered within the planning process. By identifying the potential planting locations in the local authority area, and applying them within a dispersion and deposition model, the potential magnitude of reduction in the ambient concentration of PM(10), achievable through urban tree planting, has been quantified for two UK cities. As part of the Environmental Information Systems for Planners (EISP), flow diagrams, based on planning decisions, have incorporated output from the model to make decisions on land use planning ranging from development plans and strategic planning, to development control. In this way, for any new developments that contribute to the local PM(10) level, the mitigation by planting trees can be assessed, and in some cases, reductions can be sufficient to meet air quality objectives for PM(10).  相似文献   
658.
This paper presents an assessment of air quality of the city Eskişehir, located 230 km southwest to the capital of Turkey. Only five of the major air pollutants, most studied worldwide and available for the region, were considered for the assessment. Available sulphur dioxide (SO2), particulate matter (PM), nitrogen dioxide (NO2), ozone (O3), and non-methane volatile organic carbons (NMVOCs) data from local emission inventory studies provided relative source contributions of the selected pollutants to the region.The contributions of these typical pollution parameters, selected for characterizing such an urban atmosphere, were compared with the data established for other cities in the nation and world countries. Additionally, regional ambient SO2 and PM concentrations, determined by semi-automatic monitoring at two sites, were gathered from the National Ambient Air Monitoring Network (NAAMN). Regional data for ambient NO2 (as a precursor of ozone as VOCs) and ozone concentrations, through the application of the passive sampling method, were provided by the still ongoing local air quality monitoring studies conducted at six different sites, as representatives of either the traffic-dense-, or coal/natural gas burning residential-, or industrial/rural-localities of the city. Passively sampled ozone data at a single rural site were also verified with the data from a continuous automatic ozone monitoring system located at that site. Effects of variations in seasonal-activities, newly established railway system, and switching to natural gas usage on the temporal changes of air quality were all considered for the assessment. Based on the comparisons with the national [AQCR (Air Quality Control Regulation). Ministry of Environment (MOE), Ankara. Official Newspaper 19269; 1986.] and a number of international [WHO (World Health Organization). Guidelines for Air Quality. Geneva; 2000. Downloaded in January 2006, website: http://www.who.int/peh/; EU (European Union). Council Directive 1999/30/EC relating to limit values for sulfur dioxide, nitrogen dioxide and lead in ambient air. Of J Eur Communities L 163: 14–30; 29.6.1999; EU (European Union). Council Directive 2002/3/EC relating to ozone in ambient air. Of J Eur Communities. L 67: 14–30; 9.3.2002.; USEPA (U.S. Environmental Protection Agency). National Ambient Air Quality Standards (NAAQS). Downloaded in January 2006, website: http://www.epa.gov/ttn/naaqs/] ambient air standards, among all the pollutants studied, only the annual average SO2 concentration was found to exceed one specific limit value (EU limit for protection of the ecosystem). A part of the data (VOC/NOx ratio), for determining the effects of photochemical interactions, indicated that VOC-limited regime was prevailing throughout the city.  相似文献   
659.
1 INTRODUCTION According to the Environmental Protection Law of P.R. China, and the Environmental Protection Management Method on Construction Projects the Technical Guidelines for Environmental Impact Assessment (EIA) (HJ/T 2.1~2. 3-93) have defined how environmental impact assessment should be carried out for construction projects, in terms of the general principle, methodology, contents and requirements. Technical Guidelines for Environmental Impact Assessment on the Atmosphe…  相似文献   
660.
The 5-day forward and backward trajectories of air mass transport to three Russian Arctic points for each day in April and July over a 10-year period from 1986 to 1995 have been analyzed. The important features and seasonal differences in air exchange processes in various areas of the Arctic have been investigated. Taking into account seasonal variations in aerosol scavenging mechanisms and velocities, the average contributions of large highly industrialized regions of the Russian Arctic air pollution were estimated for April and July. Reasonable correspondence between the calculated mean concentrations for six anthropogenic chemical elements (As, Ni, Pb, V, Zn, Cd) and experimentally determined values have been obtained. The atmospheric pollution transport from the Arctic was studied as yet another way of cleaning the Arctic atmosphere, in addition to the traditionally considered wet and dry depositions onto the surface. The average apportionment of conservative contaminants after passing the observation points was estimated for spring and summer. The air masses passing through the observation points in spring may take about 20–40% of pollutants out of the Arctic. In summer, however, more than 90% of pollutants transported into the Russian Arctic deposit within 5 days onto the surface inside the Arctic region. The monthly average fluxes of six anthropogenic elements onto the surface in the Russian Arctic were estimated for April and July.  相似文献   
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