全文获取类型
收费全文 | 327篇 |
免费 | 15篇 |
国内免费 | 5篇 |
专业分类
安全科学 | 8篇 |
废物处理 | 18篇 |
环保管理 | 53篇 |
综合类 | 58篇 |
基础理论 | 102篇 |
污染及防治 | 57篇 |
评价与监测 | 18篇 |
社会与环境 | 28篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 6篇 |
2022年 | 5篇 |
2021年 | 10篇 |
2020年 | 14篇 |
2019年 | 6篇 |
2018年 | 29篇 |
2017年 | 18篇 |
2016年 | 27篇 |
2015年 | 13篇 |
2014年 | 18篇 |
2013年 | 24篇 |
2012年 | 21篇 |
2011年 | 28篇 |
2010年 | 12篇 |
2009年 | 14篇 |
2008年 | 19篇 |
2007年 | 7篇 |
2006年 | 12篇 |
2005年 | 6篇 |
2004年 | 8篇 |
2003年 | 10篇 |
2002年 | 7篇 |
2001年 | 3篇 |
2000年 | 6篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有347条查询结果,搜索用时 125 毫秒
151.
Michael A. Kamboures Shishan Hu Yong Yu Julia Sandoval Paul Rieger Shiou-Mei Huang 《Journal of the Air & Waste Management Association (1995)》2013,63(8):886-901
A pilot study was conducted to evaluate the performance and agreement of several commercially available black carbon (BC) measurement instruments, when applied to the quantification of BC in light-duty vehicle (LDV) exhaust. Samples from six vehicles, three fuels, and three driving cycles were used. The pilot study included determinations of the method detection limit (MDL) and repeatability. With respect to the MDL, the real-time instruments outperformed the time-integrated instruments, with MDL = 0.12 mg/mi for the AE51 Aethalometer, and 0.15 mg/mi for the Micro Soot Sensor (MSS), versus 0.38 mg/mi for the IMPROVE_A thermal/optical method, and 0.35 mg/mi for the OT21_T Optical Transmissometer. The real-time instruments had repeatability values ranging from 30% to 35%, which are somewhat better than those of the time-integrated instruments (40–41%). These results suggest that, despite being less resource intensive, real-time methods can be equivalent or superior to time-integrated methods in terms of sensitivity and repeatability. BC mass data, from the photoacoustic and light attenuation instruments, were compared against same-test EC data, determined using the IMPROVE_A method. The MSS BC data was well correlated with EC, with R 2 = 0.85 for the composite results and R2 = 0.86 for the phase-by-phase (PBP) results. The correlation of BC, by the AE51, AE22, and OT21_T, with EC was moderate to weak. The weaker correlation was driven by the inclusion of US06 test data in the linear regression analysis. We hypothesize that test-cycle-dependent BC:EC ratios are due to the different physicochemical properties of particulate matter (PM) in US06 and Federal Test Procedure (FTP) tests. Correlation amongst the real-time MSS, PASS-1, AE51, and AE22 instruments was excellent (R2 = 0.83–0.95), below 1 mg/mi levels. In the process of investigating these BC instruments, we learned that BC emissions at sub-1 mg/mi levels can be measured and are achievable by current-generation gasoline engines.
Implications: Most comparison studies of black carbon (BC) measurement methods were carried out in the ambient air. This study assesses the agreement among various BC measurement instrument in emissions from light-duty gasoline vehicles (LDGVs) on standard test cycles, and evaluates applicability of these methods under various fuel types, driving cycles, and engine combustion technologies. This research helps to fill in the knowledge gap of BC method standardization as stated in the U.S. Environmental Protection Agency (EPA) 2011 Report to Congress on Black Carbon, and these results demonstrate the feasibility of quantification of BC at the 1 mg/mi PM standard in California Low Emission Vehicle III regulations. 相似文献
152.
Cairns E Tharumakulasingam K Athar M Yousaf M Cheng I Huang Y Lu J Yap D 《Environmental pollution (Barking, Essex : 1987)》2011,159(8-9):2003-2008
Atmospheric gaseous elemental mercury [GEM] at 1.8, 4, and 59 m above ground, in parking lots, and in indoor and outdoor air was measured in Toronto City, Canada from May 2008-July 2009. The average GEM value at 1.8 m was 1.89 ± 0.62 ng m(-3). The GEM values increased with elevation. The average GEM in underground parking lots ranged from 1.37 to 7.86 ng m(-3) and was higher than those observed from the surface parking lots. The GEM in the indoor air ranged from 1.21 to 28.50 ng m(-3), was higher in the laboratories than in the offices, and was much higher than that in the outdoor air. All these indicate that buildings serve as sources of mercury to the urban atmosphere. More studies are needed to estimate the contribution of urban areas to the atmospheric mercury budget and the impact of indoor air on outdoor air quality and human health. 相似文献
153.
Silvia Jerez Miguel Motas Jesús Benzal Julia Diaz Virginia Vidal Verónica D’Amico Andrés Barbosa 《Environmental science and pollution research international》2013,20(5):3300-3311
The presence of metals in the Antarctic environment is principally a natural phenomenon caused by geochemical characteristics of the region, although some anthropogenic activities can increase these natural levels. Antarctic penguins present several of the characteristics of useful sentinels of pollution in Antarctica such as they are long-lived species situated at the top of food web. The concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd, and Pb were determined by inductively coupled plasma–mass spectrometry in samples of liver, kidney, muscle, bone, feather, and stomach contents of gentoo, chinstrap, and Adélie penguin (12 adults, five juveniles) from carcasses of naturally dead individuals collected opportunistically in the Antarctic Peninsula area. The obtained results showed that accumulation and magnification of several elements can be occurring, so that Cd and Se reached levels potentially toxic in some specimens. The presence of human activities seems to be increasing the presence of toxic metals such as Mn, Cr, Ni, or Pb in penguins. 相似文献
154.
155.
Spatial variability of soil gas concentration and methane oxidation capacity in landfill covers 总被引:2,自引:0,他引:2
In order to devise design criteria for biocovers intended to enhance the microbial oxidation of landfill methane it is critical to understand the factors influencing gas migration and methane oxidation in landfill cover soils. On an old municipal solid waste landfill in north-western Germany soil gas concentrations (10, 40, 90 cm depth), topsoil methane oxidation capacity and soil properties were surveyed at 40 locations along a 16 m grid. As soil properties determine gas flow patterns it was hypothesized that the variability in soil gas composition and the subsequent methanotrophic activity would correspond to the variability of soil properties. Methanotrophic activity was found to be subject to high spatial variability, with values ranging between 0.17 and 9.80 g CH4 m−2 h−1. Considering the current gas production rate of 0.03 g CH4 m−2 h−1, the oxidation capacity at all sampled locations clearly exceeded the flux to the cover, and can be regarded as an effective instrument for mitigating methane fluxes. The methane concentration in the cover showed a high spatial heterogeneity with values between 0.01 and 0.32 vol.% (10 cm depth), 22.52 vol.% (40 cm), and 36.85 vol.% (90 cm). The exposure to methane raised the oxidation capacity, suggested by a statistical correlation to an increase in methane concentration at 90 cm depth. Methane oxidation capacity was further affected by the methanotroph bacteria pH optimum and nutrient availability, and increased with decreasing pH towards neutrality, and increased with soluble ion concentration). Soil methane and carbon dioxide concentration increased with lower flow resistance of the cover, as represented by the soil properties of a reduced bulk density, increase in air capacity and in relative ground level. 相似文献
156.
Tauhata L Vianna ME de Oliveira AE Ferreira AC Bragança MJ Clain AF de Faria RQ 《Journal of environmental radioactivity》2006,86(3):384-390
The Instituto de Radioprote??o e Dosimetria has been coordinating the National Intercomparison Program (PNI) for 15 years, from 1991 to 2005. The objective is to evaluate the analytical performance of the laboratories in low-level activity concentration radionuclide assays in environmental samples. This work presents an evaluation of PNI data from 42 intercomparison runs, which distributed to 22 Brazilian laboratories 2511 samples evaluating 5768 radionuclide assays involving 32 radionuclides in the period from 1991 to 2004. The laboratory performance was evaluated using the Normalized Standard Deviation used by the U.S. EPA. For comparison aims, the Normalized Deviation, used by BIPM was also applied. Laboratory performance were grouped and evaluated in three periods of 5 years each. The first period shows, an average value of good performance of 71.2%, the second shows an average of 78.6% and the last an average of 82.3%. Performance for each kind of radionuclide is also presented. 相似文献
157.
Biosynthetic origin of carbon-based secondary compounds: cause of variable responses of woody plants to fertilization? 总被引:10,自引:0,他引:10
Erkki Haukioja Vladimir Ossipov Julia Koricheva Tuija Honkanen Stig Larsson Kyösti Lempa 《Chemoecology》1998,8(3):133-139
Summary. We propose that variation in the responses of carbon-based secondary compounds to fertilization in woody plants has a biosynthetic
cause. The synthesis of phenylpropanoids and derived compounds (e.g., condensed tannins) competes directly with the synthesis of proteins, and therefore with plant growth, because of a common
precursor, phenylalanine. In contrast, the biosynthesis of terpenoids and of hydrolyzable tannins proceeds presumably without
direct competition with protein synthesis. Therefore, accelerated plant growth induced by fertilization may cause a reduction
in concentrations of phenylpropanoids but may affect less or not at all the levels of other classes of secondary compounds.
A meta-analysis based on fertilization experiments with 35 woody plant species supported the predicted differences fertilizing
significantly decreased concentrations of phenylpropanoids but not of terpenoids or hydrolyzable tannins.
Received 14 May 1998; accepted 23 June 1998. 相似文献
158.
Andrea J. Britton Julia M. Fisher 《Environmental pollution (Barking, Essex : 1987)》2010,158(5):1296-1302
The influence of applied nitrogen (N) concentration and load on thallus chemistry and growth of five terricolous alpine lichen species was investigated in a three-month N addition study. Thallus N content was influenced by both concentration and load; but the relative importance of these parameters varied between species. Growth was most affected by concentration. Thresholds for effects observed in this study support a low critical load for terricolous lichen communities (<7.5 kg N ha−1 y−1) and suggest that concentrations of N currently encountered in UK cloudwater may have detrimental effects on the growth of sensitive species. The significance of N concentration effects on sensitive species also highlights the need to avoid artificially high concentrations when designing N addition experiments. Given the sensitivity of some species to extremely low loads and concentrations of N we suggest that terricolous lichens have potential as indicators of deposition and impact in northern and alpine ecosystems. 相似文献
159.
Transpiration and Root Development of Urban Trees in Structural Soil Stormwater Reservoirs 总被引:2,自引:0,他引:2
Julia Bartens Susan D. Day J. Roger Harris Theresa M. Wynn Joseph E. Dove 《Environmental management》2009,44(4):646-657
Stormwater management that relies on ecosystem processes, such as tree canopy interception and rhizosphere biology, can be
difficult to achieve in built environments because urban land is costly and urban soil inhospitable to vegetation. Yet such
systems offer a potentially valuable tool for achieving both sustainable urban forests and stormwater management. We evaluated
tree water uptake and root distribution in a novel stormwater mitigation facility that integrates trees directly into detention
reservoirs under pavement. The system relies on structural soils: highly porous engineered mixes designed to support tree
root growth and pavement. To evaluate tree performance under the peculiar conditions of such a stormwater detention reservoir (i.e., periodically
inundated), we grew green ash (Fraxinus pennsylvanica Marsh.) and swamp white oak (Quercus bicolor Willd.) in either CUSoil or a Carolina Stalite-based mix subjected to three simulated below-system infiltration rates for
two growing seasons. Infiltration rate affected both transpiration and rooting depth. In a factorial experiment with ash,
rooting depth always increased with infiltration rate for Stalite, but this relation was less consistent for CUSoil. Slow-drainage
rates reduced transpiration and restricted rooting depth for both species and soils, and trunk growth was restricted for oak,
which grew the most in moderate infiltration. Transpiration rates under slow infiltration were 55% (oak) and 70% (ash) of
the most rapidly transpiring treatment (moderate for oak and rapid for ash). We conclude this system is feasible and provides
another tool to address runoff that integrates the function of urban green spaces with other urban needs. 相似文献
160.
The levels of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in 31 sewage sludges from different wastewater treatment plants corresponding to rural, urban and industrial areas in the Valencian Community (Spain) were analysed. Values of 5.1-346.2 ng I-TEQ kg(-1) (dry weight) were detected for sewage sludge with the highest value in one sample from an industrial area. Therefore the majority of the samples did not exceed the limit proposed (100 ng I-TEQ kg(-1)) by the [EU, 2000. Working document on sludge, 3rd draft. Brussels. Available from: http://europa.eu.int/comm/environment/waste/sludge/sludge_en.pdf] for use in agriculture. The dominant congeners for each family of compounds were 1,2,3,4,6,7,8-HpCDD and OCDD from PCDDs, and 1,2,3,4,6,7,8-HpCDF and OCDF from PCDFs. The total concentrations of PCDD/Fs were evaluated statistically through SPPS 11.0 for Windows. The principal component analysis (PCA) was used to extract two PCs as a linear combination of the original variables, one of them associated to urban+highly industrial areas and the other one to urban+low industrial areas. The linear regression method was applied and an efficient correlation was obtained between the total I-TEQ values for each sample and two of most abundant congeners (OCDF and OCDD). This expression was obtained with the results of the 31 samples analysed and a variety of data from other authors. Furthermore, several bilateral correlations between the different congeners completed the statistical analysis. 相似文献