全文获取类型
收费全文 | 627篇 |
免费 | 8篇 |
国内免费 | 18篇 |
专业分类
安全科学 | 27篇 |
废物处理 | 24篇 |
环保管理 | 154篇 |
综合类 | 58篇 |
基础理论 | 148篇 |
污染及防治 | 174篇 |
评价与监测 | 42篇 |
社会与环境 | 20篇 |
灾害及防治 | 6篇 |
出版年
2022年 | 2篇 |
2021年 | 2篇 |
2020年 | 4篇 |
2019年 | 3篇 |
2018年 | 8篇 |
2017年 | 4篇 |
2016年 | 13篇 |
2015年 | 11篇 |
2014年 | 12篇 |
2013年 | 85篇 |
2012年 | 17篇 |
2011年 | 19篇 |
2010年 | 11篇 |
2009年 | 20篇 |
2008年 | 33篇 |
2007年 | 29篇 |
2006年 | 22篇 |
2005年 | 20篇 |
2004年 | 28篇 |
2003年 | 25篇 |
2002年 | 25篇 |
2001年 | 21篇 |
2000年 | 18篇 |
1999年 | 15篇 |
1998年 | 11篇 |
1997年 | 6篇 |
1996年 | 8篇 |
1995年 | 8篇 |
1994年 | 6篇 |
1993年 | 5篇 |
1992年 | 14篇 |
1991年 | 8篇 |
1990年 | 6篇 |
1989年 | 9篇 |
1988年 | 10篇 |
1987年 | 4篇 |
1986年 | 8篇 |
1985年 | 9篇 |
1984年 | 11篇 |
1983年 | 15篇 |
1982年 | 9篇 |
1981年 | 8篇 |
1980年 | 16篇 |
1979年 | 7篇 |
1978年 | 7篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1971年 | 2篇 |
排序方式: 共有653条查询结果,搜索用时 156 毫秒
521.
Pope CA Hansen JC Kuprov R Sanders MD Anderson MN Eatough DJ 《Journal of the Air & Waste Management Association (1995)》2011,61(8):858-863
Exposure to fine particulate air pollution has been implicated as a risk factor for cardiopulmonary disease and mortality. Proposed biological pathways imply that particle-induced pulmonary and systemic inflammation play a role in activating the vascular endothelium and altering vascular function. Potential effects of fine particulate pollution on vascular function are explored using controlled chamber exposure and uncontrolled ambient exposure. Research subjects included four panels with a total of 26 healthy nonsmoking young adults. On two study visits, at least 7 days apart, subjects spent 3 hr in a controlled-exposure chamber exposed to 150-200 microg/m3 of fine particles generated from coal or wood combustion and 3 hr in a clean room, with exposure and nonexposure periods alternated between visits. Baseline, postexposure, and post-clean room reactive hyperemia-peripheral arterial tonometry (RH-PAT) was conducted. A microvascular responsiveness index, defined as the log of the RH-PAT ratio, was calculated. There was no contemporaneous vascular response to the few hours of controlled exposure. Declines in vascular response were associated with elevated ambient exposures for the previous 2 days, especially for female subjects. Cumulative exposure to real-life fine particulate pollution may affect vascular function. More research is needed to determine the roles of age and gender, the effect of pollution sources, the importance of cumulative exposure over a few days versus a few hours, and the lag time between exposure and response. 相似文献
522.
Black A McLaren RG Reichman SM Speir TW Condron LM 《Environmental pollution (Barking, Essex : 1987)》2011,159(6):1523-1535
523.
Du Preez LH Kunene N Everson GJ Carr JA Giesy JP Gross TS Hosmer AJ Kendall RJ Smith EE Solomon KR Van Der Kraak GJ 《Chemosphere》2008,71(3):546-552
Reproductive success and development of F2 offspring from F1 adult African clawed frogs (Xenopus laevis) exposed to atrazine throughout larval development and as sexually mature adults was examined. Larval X. laevis were exposed to one of four nominal concentrations of atrazine (0, 1, 10, 25 microg atrazine/l) beginning 96 hr after fertilization and continuing through two years post-metamorphosis. Clutch size and survival of offspring were used as measurement endpoints to gauge reproductive success of the F1 frogs. Larval survivorship and time to metamorphosis were used to gauge developmental success of the F2 offspring from atrazine-exposed frogs. Testes in F1 and F2 frogs were examined for incidence of anomalies, such as testicular ovarian follicles, and sex ratios in F2 offspring were investigated to determine if exposure to atrazine caused trans-generational effects (effects on F2 individuals due to exposure of F1 individuals). There were no effects of any of the studied concentrations of atrazine on clutch size of F1 frogs. There were also no effects on hatching success or time to metamorphosis. Sex ratios did not differ between F2 offspring among treatments. There was no evidence to suggest a transgenerational effect of atrazine on spawning success or reproductive development of X. laevis. This is consistent with the presence of robust populations of X. laevis in areas where they are exposed to atrazine that has been used for several decades for weed control in production of corn. Our observations also are consistent with the results of most other studies of frogs where no effects were found to be associated with exposure to atrazine. Our data do not support the hypothesis that atrazine significantly affects reproductive fitness and development of frogs. 相似文献
524.
A three-dimensional, compositional, multiphase flow simulator was used to model a field-scale test of DNAPL removal by cosolvent flooding. The DNAPL at this site was tetrachloroethylene (PCE), and the flooding solution was an ethanol/water mixture, with up to 95% ethanol. The numerical model, UTCHEM accounts for the equilibrium phase behavior and multiphase flow of a ternary ethanol-PCE-water system. Simulations of enhanced cosolvent flooding using a kinetic interphase mass transfer approach show that when a very high concentration of alcohol is injected, the DNAPL/water/alcohol mixture forms a single phase and local mass transfer limitations become irrelevant. The field simulations were carried out in three steps. At the first level, a simple uncalibrated layered model is developed. This model is capable of roughly reproducing the production well concentrations of alcohol, but not of PCE. A more refined (but uncalibrated) permeability model is able to accurately simulate the breakthrough concentrations of injected alcohol from the production wells, but is unable to accurately predict the PCE removal. The final model uses a calibration of the initial PCE distribution to get good matches with the PCE effluent curves from the extraction wells. It is evident that the effectiveness of DNAPL source zone remediation is mainly affected by characteristics of the spatial heterogeneity of porous media and the variable (and unknown) DNAPL distribution. The inherent uncertainty in the DNAPL distribution at real field sites means that some form of calibration of the initial contaminant distribution will almost always be required to match contaminant effluent breakthrough curves. 相似文献
525.
Kristine F. Stepenuck Ronald L. Crunkilton Michael A. Bozek Lizhu Wang 《Journal of the American Water Resources Association》2008,44(3):670-678
Abstract: We compared benthic macroinvertebrate assemblage structure at snag and riffle habitats in 43 Wisconsin streams across a range of watershed urbanization using a variety of stream quality metrics. Discriminant analysis indicated that dominant taxa at riffles and snags differed; Hydropsychid caddisflies (Hydropsyche betteni and Cheumatopsyche spp.) and elmid beetles (Optioservus spp. and Stenemlis spp.) typified riffles, whereas isopods (Asellus intermedius) and amphipods (Hyalella azteca and Gammarus pseudolimnaeus) predominated in snags. Analysis of covariance indicated that samples from snag and riffle habitats differed significantly in their response to the urbanization gradient for the Hilsenhoff biotic index (BI), Shannon’s diversity index, and percent of filterers, shredders, and pollution intolerant Ephemeroptera, Plecoptera, and Trichoptera (EPT) at each stream site (p ≤ 0.10). These differences suggest that although macroinvertebrate assemblages present in either habitat type are sensitive to detecting the effects of urbanization, metrics derived from different habitats should not be intermixed when assessing stream quality through biomonitoring. This can be a limitation to resource managers who wish to compare water quality among streams where the same habitat type is not available at all stream locations, or where a specific habitat type (i.e., a riffle) is required to determine a metric value (i.e., BI). To account for differences in stream quality at sites lacking riffle habitat, snag‐derived metric values can be adjusted based on those obtained from riffles that have been exposed to the same level of urbanization. Comparison of nonlinear regression equations that related stream quality metric values from the two habitat types to percent watershed urbanization indicated that snag habitats had on average 30.2 fewer percent EPT individuals, a lower diversity index value than riffles, and a BI value of 0.29 greater than riffles. 相似文献
526.
Ronald T. Green James R. Winterle James D. Prikryl 《Journal of the American Water Resources Association》2008,44(4):887-901
Abstract: Analysis of results from an electrical resistivity survey, a magnetic survey, and an aquifer test performed on the Leona River floodplain in south‐central Texas indicates that ground‐water discharge from the Edwards Aquifer through the Leona River floodplain may be as great as 91.7 Mm3/year. When combined with an estimate of 8.8 Mm3/year for surface flow in the Leona River, as much as 100.5 Mm3/year could be discharged from the Edwards Aquifer through the Leona River floodplain. A value of 11,200 acre‐ft/year (13.82 Mm3/year) has been used as the calibration target in existing ground‐water models for total discharge from Leona Springs and the Leona River. Including ground water or underflow discharge would significantly increase the calibration target in future models. This refinement would improve the conceptualization of ground‐water flow in the western portion of the San Antonio segment of the Edwards Aquifer and would thereby allow for more accurate assessment and management of the ground‐water resources provided by the Edwards Aquifer. 相似文献
527.
Abstract Chemical composition and particle size data for particulate emissions from stationary sources are required for environmental health effect assessments, air chemistry studies and for air quality modeling investigations such as source apportionment. The Information presented In this paper is directed to those individuals concerned with these environmental Investigations. In this study, particulate emissions from a group of non-ferrous smelters have been physically and chemically characterized. Emission samples were collected at the baghouse outlets from smelter furnaces and at smelter acid plant stacks at three locations; a zinc, a lead, and a copper smelter. Mass emission rate determinations were made by EPA reference methods. Cascade impactors were used to collect in-stack samples for particle size distribution measurements. Particulate samples for chemical characterization were collected on membrane filters for analysis by X-ray fluorescence spectroscopy. Development of measurement techniques required to determine the elemental composition of the total mass and sized fractions of the emission are discussed. Results of the tests at the three smelters include total mass and elemental emission rates, particle size distribution, and the elemental composition of the total particulate mass and of sized fractions from both the smelter furnaces and acid plants. The results obtained at the copper smelter may not be representative of the emissions at the many copper smelters where reverbatory furnaces have been replaced. 相似文献
528.
Walter F. McMichael Ronald E. Kruse Donald M. Hill 《Journal of the Air & Waste Management Association (1995)》2013,63(4):246-248
Road tests have been carried out in five different cities with a fleet of 300 passenger cars consisting of three different makes, half of which are equipped with the 1966 exhaust control devices required by the state of California. The performance of these devices during the first series of tests has been evaluated. All three makes of device-equipped cars produced significantly lower emissions of hydrocarbons and carbon monoxide than did similar cars tested in 1962 and 1963. There were no consistent differences among the three makes of cars with respect to carbon monoxide and hydrocarbon emissions. 相似文献
529.
Ronald D. Snee 《Journal of the Air & Waste Management Association (1995)》2013,63(2):170-175
Blood lead and air lead levels of children who lived within 32 km of a smelter in Kellogg, ID were measured in 1974 and 1975. While an analysis of the 1974 survey has appeared, the results of the 1975 survey and an evaluation of the change in blood lead levels of those children who participated in both the 1974 and 1975 surveys has not previously been discussed in the literature. It Is concluded that, for these data, in the air lead range of 0.5–5 μg/m3, the blood lead-air lead relationship can be adequately described by blood lead-air lead slope which is approximately 1.0 and at most 1.4. This slope was also found to be Independent of children’s age. It Is shown that an accurate estimate of the blood lead-air lead relationship cannot be obtained without taking proper account of selected environmental variables; specifically, pica, sex, age, father’s work status, education, and home cleanliness. 相似文献
530.
Robert L. Carpenter Ronald D. Clark Yin-Fong Su 《Journal of the Air & Waste Management Association (1995)》2013,63(6):679-681
The body of information contained in this paper is directed towards individuals concerned with the toxicology and physical state of airborne effluents from pulverized coal-fired stationary sources. A flotation/sedimentation technique was used to separate fly ash from power plant clean-up devices into light, medium, and high density fractions. Large spherical particles were selected from each fraction and examined by optical and scanning electron microscopy. Attempts were made to identify pleurospheres (filled hollow spheres) by crushing the spheres in situ under the optical microscope. In no cases were filled spheres observed, suggesting that they are not a common structure in fly ash. Several phenomena which generate hollow spheres are discussed. 相似文献