全文获取类型
收费全文 | 14191篇 |
免费 | 166篇 |
国内免费 | 121篇 |
专业分类
安全科学 | 426篇 |
废物处理 | 382篇 |
环保管理 | 2210篇 |
综合类 | 3362篇 |
基础理论 | 3365篇 |
环境理论 | 7篇 |
污染及防治 | 3568篇 |
评价与监测 | 664篇 |
社会与环境 | 420篇 |
灾害及防治 | 74篇 |
出版年
2018年 | 144篇 |
2017年 | 154篇 |
2016年 | 212篇 |
2015年 | 176篇 |
2014年 | 215篇 |
2013年 | 1017篇 |
2012年 | 356篇 |
2011年 | 492篇 |
2010年 | 347篇 |
2009年 | 466篇 |
2008年 | 511篇 |
2007年 | 538篇 |
2006年 | 488篇 |
2005年 | 375篇 |
2004年 | 401篇 |
2003年 | 412篇 |
2002年 | 371篇 |
2001年 | 497篇 |
2000年 | 356篇 |
1999年 | 244篇 |
1998年 | 168篇 |
1997年 | 161篇 |
1996年 | 194篇 |
1995年 | 191篇 |
1994年 | 230篇 |
1993年 | 198篇 |
1992年 | 194篇 |
1991年 | 189篇 |
1990年 | 225篇 |
1989年 | 208篇 |
1988年 | 174篇 |
1987年 | 171篇 |
1986年 | 151篇 |
1985年 | 170篇 |
1984年 | 155篇 |
1983年 | 166篇 |
1982年 | 166篇 |
1981年 | 167篇 |
1980年 | 155篇 |
1979年 | 153篇 |
1978年 | 152篇 |
1977年 | 135篇 |
1976年 | 139篇 |
1975年 | 117篇 |
1974年 | 146篇 |
1973年 | 130篇 |
1972年 | 128篇 |
1971年 | 106篇 |
1970年 | 107篇 |
1967年 | 116篇 |
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
791.
James W. Yeates 《Journal of Agricultural and Environmental Ethics》2017,30(1):23-35
The Farm Animal Welfare Council’s concept of a Good Life gives an idea of an animal’s quality of life that is over and above that of a mere life worth living. The concept needs explanation and clarification, in order to be meaningful, particularly for consumers who purchase farm animal produce. The concept could allow assurance schemes to apply the label to assessments of both the potential of each method of production, conceptualised in ways expected to enhance consumers’ engagement such as ‘naturalness’ and ‘freedom’; and the concept of a life worth living as a safeguard threshold below which no animal’s actual welfare should fall, based on each animal’s overall affective states. This may provide a framework for development of the Good Life concept, within scientific and sociological fields, in order to allow reliable and influential use by assessors, consumers and retailers. 相似文献
792.
C. Paul Nathanail Laurent M. M. Bakker Paul Bardos Yasuhide Furukawa Alessandro Nardella Garry Smith Jonathan W. N. Smith Gabriele Goetsche 《补救:环境净化治理成本、技术与工艺杂志》2017,28(1):9-15
Sustainable remediation is the elimination and/or control of unacceptable risks in a safe and timely manner while optimizing the environmental, social, and economic value of the work. Forthcoming International Organization for Standardization (ISO) Standard on Sustainable Remediation will allow countries without the capacity to develop their own guidance to benefit from work done over the past decade by various groups around the world. The ISO standard has progressed through the committee draft (ISO/CD 18504) and draft international standard (ISO/DIS 18504) stages. The risk‐based approach to managing the legacy of historically contaminated soil and groundwater has been incorporated into policy, legislation, and practice around the world. It helps determine the need for remediation and the end point of such remediation. Remediation begins with an options appraisal that short lists strategies that could deliver the required reduction in risk. A remediation strategy comprises one or more remediation technologies that will deliver the safe and timely elimination and/or control of unacceptable risks. The ISO standard will help assessors identify the most sustainable among the shortlisted, valid alternative remediation strategies. Practitioners presenting case studies claiming to constitute sustainable remediation should now report how they have aligned their work with the new standard. Indicators are used to compare alternative remediation strategies. The simplest metric that allows a characteristic to act as an indicator should be chosen. Weightings indicators can become a contested exercise and should only be undertaken where there is a clear desire for it by stakeholders and a clear need for it in identifying a preferred strategy. The simplest means of ranking alternative remediation strategies should be adopted. 相似文献
793.
794.
Although the use of tributyltin in antifouling paints has been banned, this compound is still a serious pollutant of the marine environment. This paper describes a unique study in which European flounder (Platichthys flesus) were chronically (8 months) exposed to bis(tri-n-butyltin)oxide (TBTO) in the water under controlled laboratory conditions. Residue levels in selected tissues (liver, muscle) and general health status indices were measured and the effects on several organs (gills, liver, mesonephros, ovary/testis, spleen, and gastrointestinal tract) were examined histopathologically. Additionally, morphometric analysis of the thymus was performed. The major finding is that exposure of flounder to 5 μg TBTO/l over a period of 8 months, resulting in body burdens comparable to high field levels, induced significant reduction of thymus volume, possibly affecting immunocompetence of the animals. Chronic exposure of European flounder to tributyltin is therefore likely to affect the general health status of this species in heavily polluted aquatic environments. 相似文献
795.
J.M. Zhang T. Wang A.J. Ding X.H. Zhou L.K. Xue C.N. Poon W.S. Wu J. Gao H.C. Zuo J.M. Chen X.C. Zhang S.J. Fan 《Atmospheric environment (Oxford, England : 1994)》2009,43(2):228-237
Knowledge on atmospheric abundance of peroxyacetyl nitrate (PAN) is important in assessing the severity of photochemical pollution, and for understanding chemical transformation of reactive odd nitrogen and its impact on the budget of tropospheric ozone (O3). In summer 2006, continuous measurements of PAN were made using an automatic GC–ECD analyzer with an on-line calibrator at a suburban site of Lanzhou (LZ) and a remote site of Mt. Waliguan (WLG) in western China, with concurrent measurements of O3, total reactive nitrogen (NOy) and carbon monoxide (CO). At LZ, several photochemical episodes were observed during the study, and the average mixing ratio of PAN (plus or minus standard deviation) was 0.76 (±0.89) ppbv with the maximum value of 9.13 ppbv, compared to an average value of 0.44 (±0.16) ppbv at remote WLG. The PAN mixing ratios in LZ exhibited strong diurnal variations with a maximum at noon, while enhanced concentrations of PAN were observed in the evening and a minimum in the afternoon at WLG. The daily O3 and PAN concentration maxima showed a strong correlation (r2 = 0.91) in LZ, with a regression slope (PAN/O3) of 0.091 ppbv ppbv?1. At WLG, six well-identified pollution plumes (lasting 2–8 h) were observed with elevated concentrations of PAN (and other trace gases), and analysis of backward particle release simulation shows that the high-PAN events at WLG were mostly associated with the transport of air masses that had passed over LZ. 相似文献
796.
J.W.S. Longhurst J.G. Irwin T.J. Chatterton E.T. Hayes N.S. Leksmono J.K. Symons 《Atmospheric environment (Oxford, England : 1994)》2009,43(1):64-78
This paper considers the evolution of attempts to control and manage air pollution, principally but not exclusively focussing upon the challenge of managing air pollution in urban environments. The development and implementation of a range of air pollution control measures are considered. Initially the measures implemented primarily addressed point sources, a small number of fuel types and a limited number of pollutants. The adequacy of such a source-control approach is assessed within the context of a changing and challenging air pollution climate. An assessment of air quality management in the United Kingdom over a 50-year timeframe exemplifies the range of issues and challenges in contemporary air quality management. The need for new approaches is explored and the development and implementation of an effects-based, risk management system for air quality regulation is evaluated. 相似文献
797.
L.J. Deacon L.J. Pankhurst G.H. Drew E.T. Hayes S. Jackson P.J. Longhurst J.W.S. Longhurst J. Liu S.J.T. Pollard S.F. Tyrrel 《Atmospheric environment (Oxford, England : 1994)》2009,43(35):5698-5701
Information on the particle size distribution of bioaerosols emitted from open air composting operations is valuable in evaluating potential health impacts and is a requirement for improved dispersion simulation modelling. The membrane filter method was used to study the particle size distribution of Aspergillus fumigatus spores in air 50 m downwind of a green waste compost screening operation at a commercial facility. The highest concentrations (approximately 8 × 104 CFU m−3) of culturable spores were found on filters with pore diameters in the range 1–2 μm which suggests that the majority of spores are emitted as single cells. The findings were compared to published data collected using an Andersen sampler. Results were significantly correlated (p < 0.01) indicating that the two methods are directly comparable across all particles sizes for Aspergillus spores. 相似文献
798.
Shelly L. Miller Peter Scaramella Joseph Campe Cynthia W. Goss Sandra Diaz-Castillo Ed Hendrikson Carolyn DiGuiseppi Jill Litt 《Atmospheric environment (Oxford, England : 1994)》2009,43(35):5661-5667
An indoor air quality assessment was conducted on 100 homes of recent Mexican immigrants in Commerce City, Colorado, an urban industrial community north of Denver. Head of households were administered a family health survey, filled out an activity diary, and participated in a home inspection. Carbon monoxide (CO) and carbon dioxide (CO2) were measured for 24 h inside the main living area and outside of the homes. Harvard Impactors were used to collect 24-h samples of PM2.5 at the same locations for gravimetric analysis. Dust samples were collected by vacuuming carpeting and flooring at four locations within the home and analyzed by ELISA for seven allergens. Mean indoor and outdoor PM2.5 levels were 27.2 and 8.5 μg m−3, respectively. Indoor PM2.5 and CO2 were elevated in homes for which the number of hours with door/window open was zero compared to homes in which the number of hours was high (>15 h). Indoor PM2.5 levels did not correlate with outdoor levels and tended to increase with number of inhabitants, and results indicate that the source of indoor particles were occupants and their activities, excluding smoking and cooking. Mean indoor CO2 and CO levels were 1170 and 2.4 ppm, respectively. Carbon monoxide was higher than the 24-h National Ambient Air Quality Standard in 3 of the homes. The predominant allergens were cat (Fel d 1) and mouse (Mus m 1) allergens, found in 20 and 34 homes, respectively. 相似文献
799.
Josephine A. Hagger Tamara S. Galloway Malcolm B. Jones 《Environmental pollution (Barking, Essex : 1987)》2009,157(7):2003-2010
A series of European Marine Sites has been designated as Special Areas of Conservation (SAC) in England. The aim of this study was to develop a practical methodology to assess the condition of SACs by applying a suite of biomarkers. Biomarkers were applied to the blue mussel Mytilus edulis and the shore crab Carcinus maenas from the Fal and Helford SAC (Cornwall). Individual biomarkers provided useful diagnostic information on the activity of certain classes of contaminants and an integrated Biomarker Response Index (BRI) was used to achieve a more holistic understanding of the condition of the SAC. The BRI indicated that the general health of both organisms was impacted in the upper part of the SAC (Fal Estuary) which correlated well with known chemical hotspots and sources of contamination. The BRI allows a pragmatic way to prioritise SAC sites that may require further investigative studies. 相似文献
800.
A new direct thermal desorption-GC/MS method: Organic speciation of ambient particulate matter collected in Golden, BC 总被引:1,自引:0,他引:1
Luyi C. Ding Fu Ke Daniel K.W. Wang Tom Dann Claire C. Austin 《Atmospheric environment (Oxford, England : 1994)》2009,43(32):4894-4902
Particulate matter having an aerodynamic diameter less than 2.5 μm (PM2.5) is thought to be implicated in a number of medical conditions, including cancer, rheumatoid arthritis, heart attack, and aging. However, very little chemical speciation data is available for the organic fraction of ambient aerosols. A new direct thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) method was developed for the analysis of the organic fraction of PM2.5. Samples were collected in Golden, British Columbia, over a 15-month period. n-Alkanes constituted 33–98% by mass of the organic compounds identified. PAHs accounted for 1–65% and biomarkers (hopanes and steranes) 1–8% of the organic mass. Annual mean concentrations were: n-alkanes (0.07–1.55 ng m−3), 16 PAHs (0.02–1.83 ng m−3), and biomarkers (0.02–0.18 ng m−3). Daily levels of these organics were 4.89–74.38 ng m−3, 0.27–100.24 ng m−3, 0.14–4.39 ng m−3, respectively. Ratios of organic carbon to elemental carbon (OC/EC) and trends over time were similar to those observed for PM2.5. There was no clear seasonal variation in the distribution of petroleum biomarkers, but elevated levels of other organic species were observed during the winter. Strong correlations between PAHs and EC, and between petroleum biomarkers and EC, suggest a common emission source – most likely motor vehicles and space heating. 相似文献