全文获取类型
收费全文 | 145篇 |
免费 | 2篇 |
国内免费 | 9篇 |
专业分类
安全科学 | 3篇 |
废物处理 | 8篇 |
环保管理 | 41篇 |
综合类 | 46篇 |
基础理论 | 28篇 |
污染及防治 | 12篇 |
评价与监测 | 9篇 |
社会与环境 | 5篇 |
灾害及防治 | 4篇 |
出版年
2023年 | 2篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2019年 | 8篇 |
2018年 | 4篇 |
2017年 | 6篇 |
2016年 | 4篇 |
2015年 | 9篇 |
2014年 | 11篇 |
2013年 | 7篇 |
2012年 | 6篇 |
2011年 | 9篇 |
2010年 | 4篇 |
2009年 | 24篇 |
2008年 | 13篇 |
2007年 | 10篇 |
2006年 | 3篇 |
2004年 | 5篇 |
2003年 | 3篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1989年 | 2篇 |
1984年 | 1篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1971年 | 4篇 |
排序方式: 共有156条查询结果,搜索用时 15 毫秒
41.
Bobby E. Price 《Journal of the American Water Resources Association》1971,7(4):676-683
ABSTRACT .A summary is presented of remarks made at a conference held at Louisiana Tech University on the possibility of diverting some of the Mississippi River water to Texas and New Mexico. The Texas Water Plan which has initiated the diversion possibility is discussed and particular reference is made to the activities of the federal and state agencies directly responsible for determining various aspects of the diversion study. These agencies include the Texas Water Development Board, Texas Water Quality Board, Louisiana Department of Public Works, State Engineer's Office of New Mexico, Mississippi River Commission, and the Bureau of Reclamation. 相似文献
42.
Wastewater treatment sludge contains valuable nutrients, yet represents a residue problem due to the amount of heavy metals,
which is one of the factors preventing the use of sludge as fertilizer. In Sweden, the government has a declared aim of closing
the ecocycles of nutrients to arable land, while at the same time the existing limit values are among the lowest in the world.
This paper focuses on the opportunities for Swedish wastewater utilities (WWUs) to manage and reduce sources of heavy metals
in order to get sludge approved and recycled.
A case study focusing on sources of the heavy metals Cd, Cu, Hg, Ni, Pb, and Zn and the WWUs ability to influence the source
by means of existing regulations was traced and categorized. A substantial fraction of the heavy metals were shown to be caused
by diffuse emissions, such as the use of goods and products in society. For most sources discussed in the paper, a WWU can
only manage the sources to a limited extent, if at all.
This study shows that the WWUs cannot manage both recycling of nutrients and a decrease in heavy metals ending up in sludge.
Diffuse emissions of heavy metals must be examined in context, not as a separate phenomenon or an issue for a single actor.
The existing environmental legislation does not handle diffuse sources, yet long-term strategies for reducing the emissions
to wastewater treatment must involve the reduction of diffuse emissions. 相似文献
43.
NOx, nitrate and sulphate emissions from a typical European passenger car diesel engine have been measured testing eight different fuels under five steady operating conditions (reproducing modes of the European transient urban/extraurban certification cycle). It is confirmed that nitrogen species compete with sulphur compounds to be adsorbed by diesel particulate matter (DPM) before being emitted into the atmosphere. This competition is found to increase with engine load, and is explained on the basis of the different specific surface and adsorption capacity of soot particles under different operating modes. When a high specific surface is available, as occurs in low load modes, both nitrates and sulphates are adsorbed by soot particles. On the contrary when a small surface is accessible, like in high load modes, sulphates are selectively adsorbed. This is specially important since sulphates are responsible for hydrocarbon retention in DPM due to the scrubbing effect. 相似文献
44.
An M. Michelsen 《Journal of the American Water Resources Association》1994,30(6):971-982
ABSTRACT: Voluntary water transfers through markets have been advocated by many diverse groups as a means to reallocate scarce water supplies in the semi-arid western U.S. Although transfers of water rights have occurred almost since the creation of prior appropriation laws over a century ago, functioning water markets have been very slow to develop and are few in number. The structure, composition, administration and transactions of one of the most well established water markets, shares in the Bureau of Reclamation, Colorado-Big Thompson project, are examined to better understand the institutional and transfer conditions that sustain an active water market. Results from a detailed study of C-BT project records reveal that between 1970 and 1993 there were 2,698 transactions through which over one-third of the project water changed ownership or type of use. Further analysis shows that the transactions involved many individual sellers and categories of buyers with different uses, including agricultural buyers. The transfer activity and efficiency of the C-BT market has lead some to suggest that it be used as a model for other markets. However, because this market has fewer institutional restrictions, a well developed infrastructure and unique market conditions, it will be difficult to transfer this model to other areas without accompanying modifications in water right administration and institutions. 相似文献
45.
Thermodynamic analysis of the role of chlorine and sulfur environments during combustion and incineration processes 总被引:1,自引:0,他引:1
Iddi S.N. Mkilaha Hong Yao Ichiro Naruse 《Journal of Material Cycles and Waste Management》2002,4(2):143-149
In order to control the emission of trace metals from combustion and incineration systems, sorbents and filters are sometimes
used. However, the effectiveness of these methods is greatly affected by the volatility of the metals and the way in which
they speciate during combustion, and afterwards during condensation, and physical or chemical sorption. Although there has
been a lot of research into the mechanisms by which trace metals speciate and subsequently appear in submicron particles,
the details of these mechanisms are not yet thoroughly understood. In this study, a chemical equilibrium approach was used
to qualitatively determine the speciation of lead, cadmium, and chromium in Cl and S environments. The reaction conditions
of sorbents were also tested numerically in order to understand the reaction behavior of metals with sorbents. This article
reports the influence of different concentrations of Cl and SO2 on Pb, Cd, and Cr speciation, as representatives of other trace elements. The partitioning behavior of metals during combustion
was also examined for Cl and S. The results obtained indicate that most metals exist in the vapor phase, even at low temperatures,
when chlorine is present. However, the addition of SO2 enhances the formation of the condensed phase, except at extremely high temperatures. This observation was not significant
for Cd or Cr. The higher the concentration of Cl the higher the retention of trace metals in the vapor phase, even at low
temperatures. Results from comparisons of the reactivities of mixed metals with Cl indicate that the presence of Fe limits
the reactivity of most trace metals with Cl except at higher concentrations. In the presence of Fe, alkali metals are the
first to react with Cl. If Fe is not present, most trace metals react with Cl, and the activity increases with higher concentrations.
On the other hand, the partitioning characteristics of S show that its presence generally means that metals remain in the
condensed phase. Sulfur is more reactive with alkali metals than with other trace metals.
Received: June 6, 2001 / Accepted: April 30, 2002 相似文献
46.
William J. Doucette Todd A. Wetzel Erik Dettenmaier Kyle Gorder 《Environmental Forensics》2018,19(3):185-190
Consumer products can emit chlorinated volatile organic compounds (CVOCs) that complicate vapor intrusion (VI) assessments. Assessment protocols acknowledge the need to remove these products during VI investigations, but they can be problematic to identify and locate. Predicting if the products cause detectable air concentrations is also difficult since emission rate information is limited and can vary with product use and age. In this study, the emission rates of 1,2-dichloroethane, trichloroethene, tetrachloroethene, and carbon tetrachloride from four consumer products identified as indoor sources during VI field investigations were measured under laboratory conditions using a flow through system. Emissions of PCE from an adhesive container tube ranged from 1.33 ± 1.13 μg/min (unopened) to 23.9 ± 2.93 μg/min (previously opened). The laboratory-measured emission rates were used to estimate indoor air concentrations, which were then compared to concentrations measured after the products placed were into an actual residence. The estimated and measured indoor air concentrations were generally comparable, showing that emission rate information can be used to determine the relative impact of internal CVOC sources. 相似文献
47.
This paper presents the impact of road user charging (RUC) on vehicle emissions through application of traffic assignment
and pollutant emission models. It presents results of an analysis of five RUC schemes on vehicle emissions in Leeds, UK for
2005. The schemes were: a £3 inner ring road cordoncharge; a double cordon with a £2 inner ring road and a £1 outer ring road
charge; and distance charges of 2, 10 and 20 p/km levied for travel within the outer cordon. Schemes were compared to a no
charge option and results presented here. Emissions are significantly reduced within the inner cordon, whilst beyond the cordon,
localised increases and decreases occur. The double cordon exhibits a similar but less marked pattern. Distance charging reduces
city-wide emissions by 10% under a 2 p/km charge, 42–49% under a 10 p/km charge and 52–59% under a 20 p/km charge. The higher
distance charges reduce emissions within the charge zone, and are also associated with elevated emissions outside the zone,
but to a lesser extent than that observed for cordon charging. 相似文献
48.
Sara Pantuliano 《Disasters》2007,31(S1):S77-S90
Despite more than 20 years of distribution of free emergency food in eastern Sudan (38 years in the case of refugees) Global Acute Malnutrition rates are currently the highest in the country. There has been no real improvement in the chronic livelihoods vulnerability that affects people in the region—particularly pastoralists. Food security must be seen from an informed livelihoods perspective. While food aid may still be required as part of transition, WFP must rethink its assistance strategy and advocate for complementarity in the efforts by development actors working across a range of sectors. Alternative models and interventions focused on the rehabilitation of markets and the development of' cargo nets' for the destitute, including cash transfers, must be developed and tested. Land tenure issues should be given particular attention. Food aid will probably remain an important element in the overall response, but its significance relative to other less developed forms of interventions should be reassessed. 相似文献
49.
Alan Carlin 《Journal of the American Water Resources Association》1971,7(2):221-227
The Sierra Club, which has long fought selected water resource projects that it believes would be environmentally damaging, has come to the conclusion in recent years that much more basic reforms are required in water resources development activities if the demands for environmental quality now evidenced by the American people are to be satisfied. These reforms should not be limited to those that would have a direct effect on the environmental aspects of proposed projects, but also many others long advocated by the economics profession that would have favorable indirect effects. Among the urgent reforms with indirect effects are those involving revision of the procedures used in evaluating proposed projects. These procedures should be revised so that future evaluations will much more accurately reflect the economic and environmental merits of proposed projects. Basic reforms of tax policies are also needed that will eliminate most of the private profit available to those who can persuade the government to increase the value of their land through the construction of water projects. Finally, some additional actions can be taken that will have a direct impact on lessening the adverse environmental impact of water projects beyond the provisions of the National Environmental Policy Act of 1969. 相似文献
50.
The paper reviews the current state of knowledge regarding sources of mercury emission in Poland. Due to the large quantities of coal burned at present, as well as taking into account existing reserves, coal remains the main energy source of energy in Poland. The data on coal consumption in Poland in the past, at present and in the future are discussed in the paper. Information on the content of mercury in Polish coals is presented.Coal combustion processes for electricity and heat production are the main source of anthropogenic mercury emission in Poland. It is expected that the current emissions will decrease in the future due to implementation of efficient control measures. These measures for emission reduction are described in the paper. Results of estimated mercury emission from coal-fired power station situated in the Upper Silesia Region, Poland are investigated. A relationship between mercury emission to the air and the mercury content in the consumed coal in power station equipped with the electrostatic precipitators (ESPs) is discussed. 相似文献