全文获取类型
收费全文 | 1238篇 |
免费 | 75篇 |
国内免费 | 460篇 |
专业分类
安全科学 | 90篇 |
废物处理 | 55篇 |
环保管理 | 107篇 |
综合类 | 736篇 |
基础理论 | 200篇 |
污染及防治 | 416篇 |
评价与监测 | 78篇 |
社会与环境 | 43篇 |
灾害及防治 | 48篇 |
出版年
2024年 | 1篇 |
2023年 | 17篇 |
2022年 | 42篇 |
2021年 | 38篇 |
2020年 | 33篇 |
2019年 | 33篇 |
2018年 | 44篇 |
2017年 | 58篇 |
2016年 | 58篇 |
2015年 | 82篇 |
2014年 | 108篇 |
2013年 | 122篇 |
2012年 | 106篇 |
2011年 | 106篇 |
2010年 | 104篇 |
2009年 | 69篇 |
2008年 | 72篇 |
2007年 | 69篇 |
2006年 | 73篇 |
2005年 | 42篇 |
2004年 | 46篇 |
2003年 | 44篇 |
2002年 | 53篇 |
2001年 | 53篇 |
2000年 | 49篇 |
1999年 | 45篇 |
1998年 | 48篇 |
1997年 | 44篇 |
1996年 | 25篇 |
1995年 | 23篇 |
1994年 | 21篇 |
1993年 | 14篇 |
1992年 | 13篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1981年 | 1篇 |
排序方式: 共有1773条查询结果,搜索用时 515 毫秒
891.
To more reasonably evaluate human intake of PBDEs via dust ingestion, bioaccessibility should be taken into account. Previously, we developed an in vitro method to determine the bioaccessibility of PBDEs in food. Here, this method was adapted to determine the bioaccessibility of PBDEs in dust and the digestion conditions that influenced the bioaccessibility of PBDEs were optimized. The digestion conditions included the incubation time of dust in the intestinal digestion solution (T), the bile concentration in the intestinal digestion solution (Cbile), and the ratio of the volume of the intestinal digestion solution to dust (R). The influence of the concentrations of individual PBDE congeners (CPBDE) on the bioaccessibility of PBDEs was also investigated. Central composite design was used to build an experimental model and set experimental parameters, and response surface methodology was used to analyze the obtained data. The results showed that the bioaccessibility of PBDEs increased with the increases of Cbile and R, and was independent of T and CPBDE. Under the digestion conditions with Cbile and R being at 4.0-7.0 g/L and 150-250, respectively, the bioaccessibility of PBDEs in the method-dust varied from 39.2% to 72.8%, which were comparable with the bioaccessibility or bioavailability of PBDEs in dust/soil in the literature. Thus, the in vitro method to measure the bioaccessibility of PBDEs in dust was established and validated. Finally, the bioaccessibility of PBDEs in four natural dust samples, which ranged from 36.1% to 43.3%, were determined using the adapted method. 相似文献
892.
Computing payment for ecosystem services in watersheds: An analysis of the Middle Route Project of South-to-North Water Diversion in China 总被引:1,自引:0,他引:1
Zhengju Dong Yan Yan Jing Duan Xiao Fu Qingrong Zhou Xiang Huang Xiangen Zhu Jingzhu Zhao 《环境科学学报(英文版)》2011,23(12):2005-2012
An improved watershed criteria model was developed in light of research on payment for ecosystem services outflows theory. 相似文献
893.
为推动株洲市现代生态城市的建设和提升株洲市的综合竞争能力,通过对"十五"期间株洲市区大气环境质量变化趋势的分析和评价,提出改善大气环境质量的对策,并预测了"十一五"期间大气环境质量.结果表明:"十五"期间株洲市区总体环境空气质量处于污染严重水平,SO2是市区空气污染中的主要污染物,其次是PM10,而NO2年均值达到环境空气质量一级标准.模式预测表明,"十一五"期间,株洲市市区环境空气中SO2、NO2和PM10的年平均浓度呈缓慢下降,环境空气质量将得到不断提高. 相似文献
894.
895.
896.
Immobilization of lead in anthropogenic contaminated soils using phosphates with/without oxalic acid 总被引:1,自引:0,他引:1
Understanding the effects of oxalic acid (OA) on the immobilization of Pb(II) in contaminated soils by phosphate materials, has considerable benefits for risk assessment and remediation strategies for the soil. A series of phosphate amendments with/without oxalic acid were applied to two anthropogenic contaminated soils. We investigated the immobilization of Pb(II) by KH2PO4, phosphate rock (PR), activated phosphate rock (APR) and synthetic hydroxyapatite (HAP) at different phosphate:Pb (P:Pb) molar ratios (0, 0.6, 2.0 and 4.0) in the presence/absence of 50 mmol oxalic acid/kg soil, respectively. The effects of treatments were evaluated using single extraction with deionized water or CaCl2, Community Bureau of Reference (BCR) sequential extraction and toxicity characteristic leaching procedure (TCLP) methods. Our results showed that the concentration of water extractable, exchangeable and TCLP-Pb all decreased with incubation time. The concentration of water-extractable Pb after 120 days was reduced by 100% when soils were amended with APR, HAP and HAP + OA, and the TCLP-Pb was < 5 mg/L for the red soil at P:Pb molar ratio 4.0.Water-soluble Pb could not be detected and the TCLP-Pb was < 5 mg/L at all treatments applied to the yellow-brown soil. BCR results indicated that APRwasmost effective, although a slight enhancement of water-soluble phosphate was detected at the P:Pbmolar ratio 4.0 at the beginning of incubation. Oxalic acid activated phosphates, and so mixing insoluble phosphates with oxalic acid may be a useful strategy to improve their effectiveness in reducing Pb bioavailability. 相似文献
897.
Sources and characteristics of fine particles over the Yellow Sea and Bohai Sea using online single particle aerosol mass spectrometer 总被引:2,自引:0,他引:2
Huaiyu Fu Mei Zheng Caiqing Yan Xiaoying Li Huiwang Gao Xiaohong Yao Zhigang Guo Yuanhang Zhang 《环境科学学报(英文版)》2015
Marine aerosols over the East China Seas are heavily polluted by continental sources. During the Chinese Comprehensive Ocean Experiment in November 2012, size and mass spectra of individual atmospheric particles in the size range from 0.2 to 2.0 μm weremeasured onboardby a single particle aerosol mass spectrometer (SPAMS). The average hourly particle number (PN) was around 4560 ± 3240 in the South Yellow Sea (SYS), 2900 ± 3970 in the North Yellow Sea (NYS), and 1700 ± 2220 in the Bohai Sea (BS). PN in NYS and BS varied greatly over 3 orders of magnitude, while that in SYS varied slightly. The size distributions were fitted with two log-normal modes. Accumulation mode dominated in NYS and BS, especially during episodic periods. Coarse mode particles played an important role in SYS. Particles were classified using an adaptive resonance theory based neural network algorithm (ART-2a). Six particle types were identified with secondary-containing, aged sea-salt, soot-like, biomass burning, fresh sea-salt, and lead-containing particles accounting for 32%, 21%, 18%, 16%, 4%, and 3% of total PN, respectively. Aerosols in BS were relatively enriched in particles from anthropogenic sources compared to SYS, probably due to emissions from more developed upwind regions and indicating stronger influence of continental outflowonmarine environment. Variation of source types dependedmainly on origins of transported air masses. This study examined rapid changes in PN, size distribution and source types of fine particles in marine atmospheres. It also demonstrated the effectiveness of high-time-resolution source apportionment by ART-2a. 相似文献
898.
Bu Duo Yunchen Zhang Lingdong Kong Hongbo Fu Yunjie Hu Jianmin Chen Lin Li A. Qiong 《环境科学学报(英文版)》2015
To understand the composition and major sources of aerosol particles in Lhasa City on the Tibetan Plateau (TP), individual particles were collected from 2 February to 8 March, 2013 in Tibet University. The mean concentrations of both PM2.5 and PM10 during the sampling were 25.7 ± 21.7 and 57.2 ± 46.7 μg/m3, respectively, much lower than those of other cities in East and South Asia, but higher than those in the remote region in TP like Nam Co, indicating minor urban pollution. Combining the observations with the meteorological parameters and back trajectory analysis, it was concluded that local sources controlled the pollution during the sampling. Transmission electron microscopy (TEM) combined with energydispersive X-ray spectra (EDS) was used to study 408 particles sampled on four days. Based on the EDS analysis, a total of 8 different particle categories were classified for all 408 particles, including Si-rich, Ca-rich, soot, K-rich, Fe-rich, Pb-rich, Al-rich and other particles. The dominant elements were Si, Al and Ca, which were mainly attributed to mineral dust in the earth's crust such as feldspar and clay. Fe-, Pb-, K-, Al-rich particles and soot mainly originated from anthropogenic sources like firework combustion and biomass burning during the sampling. During the sampling, the pollution mainly came from mineral dust, while the celebration ceremony and religious ritual produced a large quantity of anthropogenic metal-bearing particles on 9 and 25 February 2013. Cement particles also had a minor influence. The data obtained in this study can be useful for developing pollution control strategies. 相似文献
899.
Studies on the effect of the chlorine content of chlorophenols (CPs) on their adsorption from aqueous solution by mesoporous SBA-15 are important in understanding the mechanisms of CP adsorption. In this study, three CPs with different degrees of chlorine content (i.e., 2-chlorophenol, 2,6-dichlorophenol and 2,4,6-trichlorophenol) were investigated. The effects of parameters such as temperature and solution pH were studied. The results showed that CP adsorption by SBA-15 increased with increasing number of chlorine substituents and depended strongly on the temperature and solution pH. Thermodynamic parameters such as Gibbs free energy change (ΔG0), enthalpy change (ΔH0) and entropy change (ΔS0) were also calculated. By comparison of the adsorption coefficient of CPs with varying physical-chemical properties (size, hydrophobicity and electron density), we propose that hydrophobic interactions between CPs and the SBA-15 surface, as well as electron donor-acceptor (EDA) complexes between oxygen of the siloxane surface of SBA-15 (e--donor) and the πup-system of the CPs (e--acceptor), were dominant adsorption mechanisms. 相似文献
900.
Life cycle assessment of mobile phone housing 总被引:2,自引:0,他引:2
The life cycle assessment of the mobile phone housing in Motorola(China) Electronics Ltd. was carried out, in which materials flows and environmental emissions based on a basic production scheme were analyzed and assessed. In the manufacturing stage, such primary processes as polycarbonate molding and surface painting are included, whereas different surface finishing technologies like normal painting, electroplate, IMD and VDM etc. were assessed. The results showed that housing decoration plays a significant role within the housing life cycle. The most significant environmental impact from housing production is the photochemical ozone formation potential.Environmental impacts of different decoration techniques varied widely, for example, the electroplating technique is more environmentally frieodly than VDM. VDM consumes much more energy and raw material. In addition, the results of two alternative scenarios of dematerialization showed that material flow analysis and assessment is very important and valuable in selecting an environmentally friendly process. 相似文献