全文获取类型
收费全文 | 124篇 |
免费 | 3篇 |
国内免费 | 20篇 |
专业分类
安全科学 | 8篇 |
废物处理 | 4篇 |
环保管理 | 19篇 |
综合类 | 38篇 |
基础理论 | 19篇 |
污染及防治 | 49篇 |
评价与监测 | 3篇 |
社会与环境 | 7篇 |
出版年
2023年 | 5篇 |
2022年 | 6篇 |
2021年 | 6篇 |
2020年 | 3篇 |
2019年 | 1篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 2篇 |
2014年 | 3篇 |
2013年 | 5篇 |
2012年 | 6篇 |
2011年 | 12篇 |
2010年 | 7篇 |
2009年 | 13篇 |
2008年 | 11篇 |
2007年 | 5篇 |
2006年 | 6篇 |
2005年 | 3篇 |
2004年 | 7篇 |
2003年 | 10篇 |
2002年 | 4篇 |
2001年 | 5篇 |
2000年 | 2篇 |
1999年 | 5篇 |
1998年 | 1篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有147条查询结果,搜索用时 203 毫秒
31.
32.
The paper assesses options and challenges of reducing black carbon emissions from diesel vehicles in Russia. Black carbon is a product of incomplete diesel combustion and is a component of fine particulate matter. Particulate matter emissions have adverse health impacts, causing cardiopulmonary disease and lung cancer; black carbon is also a large climate forcer. Black carbon emissions from Russian diesel sources affect not only the Russian territory but also contribute to overall pollution. This paper analyzes current ecological standards for vehicles and fuel, evaluates policies for emission reductions from existing diesel vehicle fleet, and assesses Russia's attempts to encourage the use of natural gas as a vehicle fuel. Based on best practices of black carbon emission reductions, this paper provides a number of policy recommendations for Russia. 相似文献
33.
Tianyu Gao Li Han Bin Wang Guang Yang Zhenqiang Xu Limin Zeng Jianbo Zhang 《环境科学学报(英文版)》2014,26(10):2007-2017
Measurements of peroxyacetyl nitrate(PAN) were made at a Beijing urban site each August from2005 to 2009. Over this 5-year period, the average PAN concentration for August in each year increased from 3(2005) to 11.7 μg/m3(2007); however, it decreased rapidly in 2008(4.1 μg/m3).Generally, the variation over the 5 years showed a rise in the first part of the study period,followed by a decline. We considered two categories of local and regional air masses in this study, which revealed that the PAN concentration in Beijing was affected mainly by southeastern air masses. The August PAN variation was influenced predominantly by local air masses in 2005,but by 2009 regional air masses had become more important. This study showed the level and variation of PAN in the month of August in 5 consecutive years for the first time, and proved that control measures are useful in decreasing photochemical pollution; hence, these measures are probably feasible for other megacities too. Furthermore, this method of analyzing regional and local impacts might be useful for other studies as well. 相似文献
34.
俄罗斯年产天然气5000×108m3,年输天然气2400×108m3,输气干线多采用多管线并列埋设方式。大量的长输管道、加压站和地下储气库的设计和施工都必须解决相应的环境保护问题。在河床处多采用埋管的办法;在沙漠地带要尽可能避开流沙地区;在永冻地区应注意输气管道的加热效应;过铁路的交叉口应设计自动监测系统;在确定管道线路时,必须注意生态保护;用植树绿化等方法尽量减轻加压站内燃气轮机发出的噪音危害;地下储气库的环境保护重点是回注水的处理。最后阐述了管道等输气工程的工作程序及所使用的法规和标准等。 相似文献
35.
36.
Johnson DL 《Environmental geochemistry and health》2008,30(6):589-596
This work introduces a spatially resolved quantitative model, based on conservation of mass and first order transfer kinetics,
for following the transport and redistribution of outdoor soil to, and within, the indoor environment by track-in on footwear.
Implementations of the DIRT model examined the influence of room size, rug area and location, shoe size, and mass transfer
coefficients for smooth and carpeted floor surfaces using the ratio of mass loading on carpeted to smooth floor surfaces as
a performance metric. Results showed that in the limit for large numbers of random steps the dual aspects of deposition to
and track-off from the carpets govern this ratio. Using recently obtained experimental measurements, historic transport and
distribution parameters, cleaning efficiencies for the different floor surfaces, and indoor dust deposition rates to provide
model boundary conditions, DIRT predicts realistic floor surface loadings. The spatio-temporal variability in model predictions
agrees with field observations and suggests that floor surface dust loadings are constantly in flux; steady state distributions
are hardly, if ever, achieved.
A contribution from ESF Center for the Urban Environment. 相似文献
37.
Wenming Dong Jiamin Wan Tetsu K. Tokunag Benjamin Gilbert Kenneth H. Williams 《环境科学学报(英文版)》2017,29(7):24-32
In order to understand the transport and humification processes of dissolved organic matter(DOM) within sediments of a semi-arid floodplain at Rifle,Colorado,fluorescence excitation–emission matrix(EEM) spectroscopy,humification index(HIX) and specific UV absorbance(SUVA) at 254 nm were applied for characterizing depth and seasonal variations of DOM composition.Results revealed that late spring snowmelt leached relatively fresh DOM from plant residue and soil organic matter down into the deeper vadose zone(VZ).More humified DOM is preferentially adsorbed by upper VZ sediments,while non-or lesshumified DOM was transported into the deeper VZ.Interestingly,DOM at all depths undergoes rapid biological humification process evidenced by the products of microbial by-product-like(i.e.,tyrosine-like and tryptophan-like) matter in late spring and early summer,particularly in the deeper VZ,resulting in more humified DOM(e.g.,fulvic-acid-like and humic-acid-like substances) at the end of year.This indicates that DOM transport is dominated by spring snowmelt,and DOM humification is controlled by microbial degradation,with seasonal variations.It is expected that these relatively simple spectroscopic measurements(e.g.,EEM spectroscopy,HIX and SUVA) applied to depth-and temporally-distributed pore-water samples can provide useful insights into transport and humification of DOM in other subsurface environments as well. 相似文献
38.
Solid-state 15N NMR was applied to the aqueous extracts of a 13C-enriched plant slurry (Lolium perenne), anaerobically incubated with 15N3-trinitrotoluene (TNT). Almost all 15N3-TNT transformation products became covalently bound to the plant-derived organic material extractable with water. DCPMAS
15N 13C NMR revealed a three-step reaction scheme. After reduction of TNT, the aryl amines are acetylated. Subsequent alkylation
of the resulting amides strengthens the incorporation of TNT-transformation products into humic material. Comparable results
have been recently obtained under aerobic conditions, which indicates that this pathway is a common process during biological
TNT transformation. 相似文献
39.
Carmen Difiglio Dolf Gielen 《Mitigation and Adaptation Strategies for Global Change》2007,12(3):387-405
If hydrogen (H2) is to significantly reduce greenhouse gas emissions and oil use, it needs to displace conventional transport fuels and be
produced in ways that do not generate significant greenhouse gas emissions. This paper analyses alternative ways H2 can be produced, transported and used to achieve these goals. Several H2 scenarios are developed and compared to each other. In addition, other technology options to achieve these goals are analyzed.
A full fuel cycle analysis is used to compare the energy use and carbon (C) emissions of different fuel and vehicle strategies.
Fuel and vehicle costs are presented as well as cost-effectiveness estimates. Lowest hydrogen fuel costs are achieved using
fossil fuels with carbon capture and storage. The fuel supply cost for a H2 fuel cell car would be close to those for an advanced gasoline car, once a large-scale supply system has been established.
Biomass, wind, nuclear and solar sources are estimated to be considerably more expensive. However fuel cells cost much more
than combustion engines. When vehicle costs are considered, climate policy incentives are probably insufficient to achieve
a switch to H2. The carbon dioxide (CO2) mitigation cost would amount to several hundred US$ per ton of CO2. Energy security goals and the eventual need to stabilize greenhouse gas concentrations could be sufficient. Nonetheless,
substantial development of related technologies, such as C capture and storage will be needed. Significant H2 use will also require substantial market intervention during a transition period when there are too few vehicles to motivate
widely available H2 refueling.
相似文献
Dolf GielenEmail: |
40.
Mahsa Kheirandish Chunjiang An Zhi Chen Xiaolong Geng Michel Boufadel 《Frontiers of Environmental Science & Engineering》2022,16(5):61