全文获取类型
收费全文 | 454篇 |
免费 | 16篇 |
国内免费 | 95篇 |
专业分类
安全科学 | 28篇 |
废物处理 | 31篇 |
环保管理 | 32篇 |
综合类 | 139篇 |
基础理论 | 78篇 |
污染及防治 | 199篇 |
评价与监测 | 27篇 |
社会与环境 | 23篇 |
灾害及防治 | 8篇 |
出版年
2024年 | 1篇 |
2023年 | 7篇 |
2022年 | 21篇 |
2021年 | 16篇 |
2020年 | 17篇 |
2019年 | 7篇 |
2018年 | 10篇 |
2017年 | 9篇 |
2016年 | 13篇 |
2015年 | 12篇 |
2014年 | 27篇 |
2013年 | 54篇 |
2012年 | 38篇 |
2011年 | 39篇 |
2010年 | 13篇 |
2009年 | 25篇 |
2008年 | 25篇 |
2007年 | 50篇 |
2006年 | 21篇 |
2005年 | 19篇 |
2004年 | 13篇 |
2003年 | 31篇 |
2002年 | 13篇 |
2001年 | 18篇 |
2000年 | 12篇 |
1999年 | 4篇 |
1998年 | 3篇 |
1997年 | 6篇 |
1996年 | 4篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 5篇 |
1986年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1979年 | 4篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有565条查询结果,搜索用时 15 毫秒
481.
Li Yuan Jinjin Cheng Qian Chu Xiu Ji Jianjun Yuan Fayun Feng 《Journal of environmental science and health. Part. B》2013,48(8):693-701
The bioconcentration and elimination of racemic benalaxyl (BX) in trout liver microsomes and in juvenile rainbow trout (Oncorhynchus mykiss) were investigated to determine whether the fish can bioconcentrate and degrade this fungicide enantioselectively. Both enantiomers of BX were extracted with organic solvents and evaluated using high-performance liquid chromatography. In the microsomes, BX degradation followed first-order kinetics, and the S?(+) enantiomer of BX was eliminated twice as rapidly as the R?(?) enantiomer, resulting in residues enriched for R?(?)?BX. In vivo experiment, chiral analysis showed an obvious selective bioconcentration of BX based on statistically altered enantiomer fractions (EFs) in the fish compared with the values in the water. The R?(?)?BX was initially preferentially bioconcentrated by rainbow trout and then dissipated more slowly than its antipode. The mean half-lives for individual enantiomers were calculated as 31.6 h for R?(?)?BX and 20.3 h for the S?(+)?form. The results of the study showed that the degradation of BX enantiomers was stereoselective in rainbow trout. 相似文献
482.
Phung DT Connell D Miller G Hodge M Patel R Cheng R Abeyewardene M Chu C 《Chemosphere》2012,87(4):294-300
Chlorpyrifos is the most common organophosphate insecticide registered for use in Vietnam and is widely used in agriculture, particularly rice farming. However, chlorpyrifos exposure to and adverse effects on farmers has not been evaluated. In this study, biological monitoring of chlorpyrifos exposure in a group of rice farmers was conducted after a typical application event using back-pack spraying.Urine samples (24 h) were collected from the rice farmers before and post insecticide application. Samples were analysed for 3,5,6-trichloropyridinol (TCP), the major urinary metabolite of chlorpyrifos, using an enzymatic pre-treatment before extraction followed by HPLC-MS/MS. Absorbed Daily Dose (ADD) of chlorpyrifos for farmers were then estimated from urinary TCP levels, expressed as μg g−1 creatinine. The analytical method for urinary TCP had a low detection limit (0.6 μg L−1), acceptable recovery values (80-114%), and low relative percentage differences in duplicate and repeated samples.Post-application chlorpyrifos ADD of farmers varied from 0.4 to 94.2 μg kg−1 (body weight) d−1 with a mean of 19.4 μg kg−1 d−1 which was approximately 80-fold higher than the mean baseline exposure level (0.24 μg kg−1 d−1). Hazard Quotients (ratio of the mean ADD for rice farmers to acute oral reference dose) calculated using acute oral reference doses recommended by United States and Australian agencies varied from 2.1 (Australian NRA), 4.2 (US EPA) to 6.9 (ATSDR).Biological monitoring using HPLC-MS/MS analysis of urinary TCP (24 h) was found to be an effective method for measuring chlorpyrifos exposure among farmers. This case study found that Vietnamese rice farmers had relatively high exposures to chlorpyrifos after application, which were likely to have adverse health effects. 相似文献
483.
484.
Yinghui Mo Liping Sun Lu Zhang Jianxin Li Jixiang Li Xiuru Chu Liang Wang 《Frontiers of Environmental Science & Engineering》2023,17(4):49
485.
Paul Chiou Wei Tang Che-Jen Lin Hsing-Wei Chu T. C. Ho 《Environmental Modeling and Assessment》2009,14(3):333-350
Speciated samples of PM2.5 were collected at a site in Jefferson County, Texas by US EPA (Environmental Protection Agency) from July of 2003 to August
of 2005. A total of 269 samples with 52 species were measured; however, 22 species were excluded in this study because of
too many below-detection-limit data. The data set was analyzed by positive matrix factorization (PMF) to infer the sources
of PM observed at the site. The analysis identified ten sources: sulfate-rich secondary aerosol I (35.9%), sulfate-rich secondary
aerosol II (21.0%), cement/carbon-rich (11.7%), wood smoke (8.8%), metal processing (6.3%), motor vehicle/road dust (5.7%),
nitrate-rich secondary aerosol (3.3%), soil (3.2%), sea salt (2.6%), and chloride depleted marine aerosol (1.6%). Sulfate
and nitrate mainly exist as salts. The two sulfate-rich secondary aerosols account for almost 57% of the PM2.5 mass concentration. The factor containing highest concentrations of Cl and Na was attributed to sea salt due to the proximity
of the monitoring site to the Gulf of Mexico. The chloride depleted marine aerosol was related to the sea salt aerosol. Cement/carbon-rich,
wood smoke, metal processing, and motor vehicle/road dust factor were likely to be the local sources. 相似文献
486.
Using a hybrid approach to optimize experimental network design for aquifer parameter identification
Liang-Cheng Chang Hone-Jay Chu Yu-Pin Lin Yu-Wen Chen 《Environmental monitoring and assessment》2010,164(1-4):133-142
The main objective of this study is to evaluate the land-use change and its relationship with its driving factors in the loess hilly region. In this study, a case study was carried out in Pengyang County. We set two land-use demand scenarios (a baseline scenario (scenario 1) and a real land-use requirement scenario (scenario 2)) during year 2001–2005 via assuming the effect of driving factors on land-use change keeps stable from 1993 to 2005. Two simulated land-use patterns of 2005 are therefore achieved accordingly by use of the conversion of land use and its effects model at small regional extent. Kappa analyses are conducted to compare each simulated land-use pattern with the reality. Results show that (1) the associated kappa values were decreased from 0.83 in 1993–2000 to 0.27 (in scenario 1) and 0.23 (in scenario 2) in 2001–2005 and (2) forest and grassland were the land-use types with highest commission errors, which implies that conversion of both the land-use types mentioned above is the main determinant of change of kappa values. Our study indicates the land-use change was driven by the synthetic multiply factors including natural and social–economic factors (e.g., slope, aspect, elevation, distance to road, soil types, and population dense) in 1993–2000 until “Grain for Green Project” was implemented and has become the dominant factor in 2001–2005. 相似文献
487.
Tomonori Ishigaki Chu Van Chung Nguyen Nhu Sang Michihiko Ike Koji Otsuka Masato Yamada Yuzo Inoue 《Journal of Material Cycles and Waste Management》2008,10(2):165-172
A methodology for estimating the methane emissions from waste landfills in Hanoi, Vietnam, as part of a case study on Asian
cities, was derived based on a survey of documents and statistics related to waste management, interviews with persons in
charge, and field investigations at landfill sites. The waste management system in Hanoi was analyzed to evaluate the methane
emissions from waste landfill sites. The quantity of waste deposited into the landfill was evaluated from an investigation
of the waste stream. The composition of municipal waste was surveyed in several districts in the Hanoi city area, and the
quantities of degradable organic waste that had been deposited into landfill for the past 15 years were estimated. Field surveys
on methane emissions from landfills of different ages (0.5, 2, and 8 years) were conducted and their methane emissions were
estimated to be 120, 22.5, and 4.38 ml/min/m2, respectively. The first-order reaction rate of methane generation was obtained as 0.51/year. Methane emissions from waste
landfills were calculated by a first-order decay model using this emission factor and the amount of landfilled degradable
waste. The estimates of methane emissions using the model accorded well with the estimates of the field survey. These results
revealed that methane emissions from waste landfills estimated by regional-specific and precise information on the waste stream
are essential for accurately determining the behavior of methane emissions from waste landfills in the past, present, and
future. 相似文献
488.
Thuoc Van Chu Jean-Pascal Torréton Xavier Mari Huyen Minh Thi Nguyen Kha Thi Pham Thu The Pham Thierry Bouvier Yvan Bettarel Olivier Pringault Corinne Bouvier Emma Rochelle-Newall 《Environmental monitoring and assessment》2014,186(12):8555-8572
Phytoplankton diversity and abundance in estuarine systems are controlled by many factors. Salinity, turbidity, and inorganic nutrient concentrations and their respective ratios have all been proposed as principal factors that structure phytoplankton diversity and influence the emergence of potentially toxic species. Although much work has been conducted on temperate estuaries, less is known about how phytoplankton diversity is controlled in tropical, monsoonal systems that are subject to large, seasonal shifts in hydrology and to rapidly changing land use. Here, we present the results of an investigation into the factors controlling phytoplankton species composition and distribution in a tropical, monsoonal estuary (Bach Dang estuary, North Vietnam). A total of 245 taxa, 89 genera from six algal divisions were observed. Bacillariophyceae were the most diverse group contributing to 51.4 % of the microalgal assemblage, followed by Dinophyceae (29.8 %), Chlorophyceae (10.2 %), Cyanophyceae (3.7 %), Euglenophyceae (3.7 %) and Dictyochophyceae (1.2 %). The phytoplankton community was structured by inorganic nutrient ratios (DSi:DIP and DIN:DIP) as well as by salinity and turbidity. Evidence of a decrease in phytoplankton diversity concomitant with an increase in abundance and dominance of certain species (e.g., Skeletonema costatum) and the appearance of some potentially toxic species over the last two decades was also found. These changes in phytoplankton diversity are probably due to a combination of land use change resulting in changes in nutrient ratios and concentrations and global change as both rainfall and temperature have increased over the last two decades. It is therefore probable in the future that phytoplankton diversity will continue to change, potentially favoring the emergence of toxic species in this system. 相似文献
489.
Landfill leachate contains a high concentration of ammoniacal substances which can be a potential supply of N for plants. A bioassay was conducted using seeds of Brassica chinensis and Lolium perenne to evaluate the phytotoxicity of the leachate sample. A soil column experiment was then carried out in a greenhouse to study the effect of leachate on plant growth. Two grasses (Paspalum notatum and Vetiver zizanioides) and two trees (Hibiscus tiliaceus and Litsea glutinosa) were irrigated with leachate at the EC50 levels for 12 weeks. Their growth performance and the distribution of N were examined and compared with columns applied with chemical fertilizer. With the exception of P. notatum, plants receiving leachate and fertilizer grew better than those receiving water alone. The growth of L. glutinosa and V. zizanioides with leachate irrigation did not differ significantly from plants treated with fertilizer. Leachate irrigation significantly increased the levels of NHx-N in soil. Although NOx-N was below 1 mg N L−1 in the leachate sample, the soil NOx-N content increased by 9-fold after leachate irrigation, possibly as a result of nitrification. Leachate irrigation at EC50 provided an N input of 1920 kg N ha−1 over the experimental period, during which up to 1050 kg N ha−1 was retained in the soil and biomass, depending on the type of vegetation. The amount of nutrient added seems to exceed beyond the assimilative capability. Practitioners should be aware of the possible consequence of N saturation when deciding the application rate if leachate irrigation is aimed for water reuse. 相似文献
490.
沉积物有机碳空间分布特征及其来源是盐沼碳循环研究的一个关键问题。该研究分析了长江口崇明东滩盐沼表层沉积物样品总有机碳(TOC)、总氮(TN)和稳定碳同位素(δ13C)等参数。研究表明:东滩表层沉积物TOC和TN的平均值分别为7. 70±3. 74和0. 74±0. 32 g/kg,两者均表现为自北向南减少的分布趋势。沉积物δ13C平均值为-25. 05±1. 21‰,三元混合模型模拟计算结果表明东滩沉积物有机碳主要来源于悬浮颗粒物(43. 53±22. 44%)和植被(43. 29±24. 82%),底栖微藻贡献率较低(13. 20±8. 40%)。东滩北部沉积物表现为高悬沙贡献-低植被贡献-高有机碳含量特征,中南部表现高植被贡献-低悬沙贡献-低有机碳含量的特点。 相似文献