全文获取类型
收费全文 | 322篇 |
免费 | 2篇 |
国内免费 | 7篇 |
专业分类
安全科学 | 10篇 |
废物处理 | 18篇 |
环保管理 | 77篇 |
综合类 | 31篇 |
基础理论 | 97篇 |
污染及防治 | 70篇 |
评价与监测 | 12篇 |
社会与环境 | 15篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 1篇 |
2021年 | 7篇 |
2020年 | 4篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 10篇 |
2016年 | 9篇 |
2015年 | 10篇 |
2014年 | 4篇 |
2013年 | 30篇 |
2012年 | 16篇 |
2011年 | 26篇 |
2010年 | 11篇 |
2009年 | 8篇 |
2008年 | 22篇 |
2007年 | 15篇 |
2006年 | 16篇 |
2005年 | 17篇 |
2004年 | 10篇 |
2003年 | 9篇 |
2002年 | 21篇 |
2001年 | 13篇 |
2000年 | 2篇 |
1999年 | 6篇 |
1998年 | 3篇 |
1997年 | 7篇 |
1996年 | 1篇 |
1995年 | 6篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1983年 | 5篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 3篇 |
1966年 | 1篇 |
排序方式: 共有331条查询结果,搜索用时 15 毫秒
261.
Creating sense of community: The role of public space 总被引:3,自引:0,他引:3
Jacinta Francis Billie Giles-Corti Lisa Wood Matthew Knuiman 《Journal of environmental psychology》2012
A strong sense of community has been associated with improved wellbeing, increased feelings of safety and security, participation in community affairs and civic responsibility. Although interest in how the broader built environment influences sense of community is gaining momentum, there is a dearth of empirical research examining the association between sense of community and the quality of public space. This study investigates the relationship between four public spaces – Public Open Space (POS), community centres, schools and shops – and sense of community in residents of new housing developments in the Perth metropolitan area, Western Australia. Data was obtained from a cross-sectional survey (n = 911), a POS audit, and Geographical Information Systems, and analysed using linear regression. The perceived quality of neighbourhood POS and shops was significantly and positively associated with sense of community. This relationship appears to be unaffected by how frequently people use these spaces. High quality public spaces may be important settings for enhancing sense of community within residents of new housing developments. 相似文献
262.
Hanwant B. Singh William Viezee Warren B. Johnson Francis L. Ludwig 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1009-1017
A background of ozone (O3), principally of stratospheric origin, is present in the lower free troposphere. Typical mean O3 levels of 50 ppb, 40 ppb, and 30 ppb are encountered here in spring, summer, and fall, respectively. Maximum hourly O3 concentrations which are twice these mean values can be expected. Ozone from the free troposphere is routinely brought down to ground level under turbulent atmospheric conditions. Deep and rapid Intrusions of stratospheric air into the lower troposphere are associated with low-pressure troughs and occur regularly. In the mid troposphere, O3 levels as high as 300 ppb are found within these intrusions. Observational data showing these intrusions, containing high O3 concentrations, to directly reach ground level are currently lacking. Over the United States, an intrusion was present aloft on 8 9% of the days in 1978. The frequency, however, is somewhat reduced in summer and a northward movement is evident. During 1978, no intrusion occurred south of 30°N between June and August and none south of 40 °N in August. The hypothesis that low levels of stratospheric O3 produce disproportionately large amounts of O3 in the polluted atmosphere cannot be supported from currently known chemistry but should be studied further. The experimental technique involving a 7Be/O3 ratio to estimate the daily stratospheric component of ground level O3 is unverified and considered to be inadequate for air quality applications. Estimates resulting from such a technique are considered uncertain by a factor of more than three. Specially designed aircraft studies provide the best means to determine quantitatively the impact of stratospheric O3 on ground level air quality. 相似文献
263.
Shymko JL Farenhorst A Zvomuya F 《Journal of environmental science and health. Part. B》2011,46(4):301-312
The herbicide 2,4-D [2,4-(dichlorophenoxy) acetic acid] is a widely used broadleaf control agent in cereal production systems. Although 2,4-D soil-residual activity (half-lives) are typically less than 10 days, this herbicide also has as a short-term leaching potential due to its relatively weak retention by soil constituents. Herbicide residual effects and leaching are influenced by environmental variables such as soil moisture and temperature. The objective of this study was to determine impacts of these environmental variables on the magnitude and extent of 2,4-D mineralization in a cultivated undulating Manitoba prairie landscape. Microcosm incubation experiments were utilized to assess 2,4-D half-lives and total mineralization using a 4 × 4 × 3 × 2 factorial design (with soil temperature at 4 levels: 5, 10, 20 and 40°C; soil moisture at 4 levels: 60, 85, 110, 135 % of field capacity; slope position at 3 levels: upper-, mid- and lower-slopes; and soil depth at 2 levels: 0-5 cm and 5-15 cm). Half-lives (t(?)) varied from 3 days to 51 days with the total 2,4-D mineralization (M(T)) ranging from 5.8 to 50.9 %. The four-way interaction (temperature × moisture × slope × depth) significantly (p < 0.001) influenced both t(?) and M(T). Second-order polynomial equations best described the relations of temperature with t(?) and M(T) as was expected from a biological system. However, the interaction and variability of t(?) and M(T) among different temperatures, soil moistures, slope positions, and soil depth combinations indicates that the complex nature of these interacting factors should be considered when applying 2,4-D in agricultural fields and in utilizing these parameters in pesticide fate models. 相似文献
264.
Martin FL 《Chemosphere》2007,69(6):841-848
A battery of short-term in vitro assays and/or in vivo protocols to evaluate single-agent mutagenicity and/or genotoxicity is available. However, a protocol to assess the effect(s) of complex mixtures in vivo following a positive test finding in vitro remains difficult. Complex interactions may occur in vivo because component pharmacokinetics increases the unpredictability of pharmacodynamic outcomes. The question arises as to whether in vitro mutagenic component(s) of a complex mixture, probably unidentified, reach target organ(s) in vivo at a sufficient concentration. To address the issue of an in vitro positive, standard in vivo chromosome damage assays to test both mixtures and fractions could be conducted but, to assess site-of-contact effects, the alkaline single cell-gel electrophoresis ("comet") assay or DNA reactivity (e.g., (32)P-postlabelling of DNA adducts) might be employed. A newer approach may be the derivation of a "biochemical-cell fingerprint" of potential target sites using infrared microspectroscopy. There is interest in platforms such as gene expression, proteomics, epigenomics or metabolomics as biomarkers of signature genotoxic or non-genotoxic mechanisms. One still needs to address whether a mutagenic and/or genotoxic component reaches a target organ. An approach to track levels of target-organ exposure may be to radio-label components with a short-lived positron-emitting radionuclide. The parent compound retains its physicochemical properties whilst allowing non-invasive in vivo tissue-specific imaging. However, determining target-organ concentration(s) and effect(s) in vivo remains a difficult challenge. 相似文献
265.
266.
267.
Michael P. Harris Francis Daunt Maria I. Bogdanova José J. Lahoz-Monfort Mark A. Newell Richard A. Phillips Sarah Wanless 《Marine Biology》2013,160(11):2877-2889
Miniature geolocator loggers (Global Location Sensing, GLS) that provide daily locations of birds have revolutionised the study of winter ecology and migration patterns of seabirds. A long-term study of ringing recoveries and analyses of heavy metals and pollutants in tissues of Atlantic puffins Fratercula arctica from the Isle of May, south-east Scotland, suggested that this population wintered mainly within the North Sea. However, deployment of GLS devices over the 2007/2008 winter showed that many breeding birds made major excursions into the east Atlantic. This winter was the second of two when survival was extremely low (survival in 2006/2007 and 2007/2008 was 0.696 and 0.695, respectively, compared to the average of 0.922 over the period 1984/1985–2005/2006). These low rates of survival suggested that the unexpected use of the Atlantic might have been associated with unusually poor conditions in the North Sea as indicated by very low breeding success in 2007. Survival rate returned to previous levels in 2008/2009 providing the opportunity to test whether higher survival was associated with birds remaining in the North Sea, or whether movements into the Atlantic are a feature of this population unrelated to survival. Accordingly, geolocators were deployed over the 2009/2010 winter when adult survival was subsequently established to be high (0.913). We found greater support for the hypothesis that winter distribution is not associated with survival. Thus, 8 (40 %) of 20 individuals followed in 2009/2010 went into the Atlantic, a rate not significantly different from 11 (58 %) of the 19 followed in the 2007/2008 winter. Indeed, birds actually spent longer in the Atlantic and used a wider variety of areas in 2009/2010, although the time spent away from the colony was significantly shorter than in 2007/2008. Since our data were from individuals that survived, remaining in or moving out of the North Sea can both be successful strategies during winters when the population as a whole shows either high or low survival rates. Unfortunately, we do not know where birds that died had gone, and hence, the relative survival of birds that did or did not move into the Atlantic. Determining the link between survival and wintering area for any seabird remains a formidable challenge and will have to await the development of technologies that can determine both where and when birds die. 相似文献
268.
Jock W. Young Matt J. Lansdell Robert A. Campbell Scott P. Cooper Francis Juanes Michaela A. Guest 《Marine Biology》2010,157(11):2347-2368
We examined the feeding ecology and niche segregation of the ten most abundant fish species caught by longline operations
off eastern Australia between 1992 and 2006. Diets of 3,562 individuals were examined. Hook timer data were collected from
a further 328 fish to examine feeding behaviour in relation to depth and time of day. Prey biomass was significantly related
to predator species, predator length and year and latitude of capture. Although the fish examined fed on a mix of fish, squid
and crustacea, fish dominated the diet of all species except small albacore (Thunnus alalunga) which fed mainly on crustacea and large swordfish (Xiphias gladius) and albacore which fed mainly on squid. Cannibalism was observed in lancetfish (Alepisaurus spp.). Multidimensional scaling identified three species groups based on their diet composition. One group consisted of yellowfin
tuna (T. albacares), striped marlin (Tetrapturus audax) and dolphinfish (Coryphaena hippurus); a second group consisted of bigeye tuna (T. obesus), swordfish and albacore; and a third consisted of southern bluefin tuna (T. maccoyii) and blue shark (Prionace glauca). Of note was the separation of mako shark (Isurus oxyrhynchus) and lancetfish from all other predators. Prey length generally increased with increasing predator length although even large
predators fed on a wide range of prey lengths including very small prey. Overall, differences in prey type and size, feeding
times and depths were noted across the range of species examined to the extent that predators with overlapping prey, either
in type or size, fed at different times of the diel period or at different depths. Taken together these data provide evidence
for feeding niche segregation across the range of oceanic top predators examined. 相似文献
269.
Rajendram Thivyatharsan H. A. Y. R. Gunarathna Benedict Francis Antony Basnayake Periyathamby Kuruparan 《Journal of Material Cycles and Waste Management》2012,14(1):27-37
The objective of the study was to develop a low cost and environmentally friendly liner system for a landfill bioreactor to
harness energy from waste. The landfill bioreactor test cell was constructed and evaluated for performance under dry tropical
conditions of Sri Lanka. The research was carried out from March 2009 to September 2010. The clay-waste polyethylene-clay
composite liner system was developed and permeability was tested. The permeability values of the liner under both saturated
and unsaturated conditions at the high estimated hydraulic head of 86.2 cm were in between 6.3 × 10−8 and 2.6 × 10−8 cm/s. The permeability of the liner under waste filled condition varied between 2.17 × 10−9 and 8.15 × 10−9 cm/s, which satisfies the standard permeability value. Thus, the results were below the minimum requirement at very high
estimated leachate head. After loading the test cell, leachate and permeate characteristics were analyzed for 273 days, from
January 2010 to September 2010. The study showed the relationships among various parameters including pH, electrical permeability,
chemical oxygen demand, biological oxygen demand, ammonia, nitrate, phosphate, total solids, volatile solids, total suspended
solids and volatile suspended solids. The results of the analysis indicated that there are significant differences in the
values of leachate and permeate parameters. The permeate parameters had values very much lower than those of leachate. It
reveals that the clay-waste polyethylene-clay composite liner system reduced the concentration of these parameters when the
leachate passed through the liner. The biofilm formed in waste polyethylene within the liner may have degraded most of organic
materials found in the leachate when it passed through the liner. Therefore, the clay-waste polyethylene-clay composite liner
system can be applied for full scale landfill bioreactors, particularly for Asian developing countries, due to better performance
and more environmentally friendly characteristics. 相似文献
270.