全文获取类型
收费全文 | 847篇 |
免费 | 7篇 |
国内免费 | 37篇 |
专业分类
安全科学 | 15篇 |
废物处理 | 50篇 |
环保管理 | 52篇 |
综合类 | 60篇 |
基础理论 | 126篇 |
污染及防治 | 462篇 |
评价与监测 | 79篇 |
社会与环境 | 43篇 |
灾害及防治 | 4篇 |
出版年
2023年 | 33篇 |
2022年 | 163篇 |
2021年 | 155篇 |
2020年 | 49篇 |
2019年 | 46篇 |
2018年 | 44篇 |
2017年 | 57篇 |
2016年 | 50篇 |
2015年 | 29篇 |
2014年 | 41篇 |
2013年 | 60篇 |
2012年 | 25篇 |
2011年 | 26篇 |
2010年 | 10篇 |
2009年 | 17篇 |
2008年 | 20篇 |
2007年 | 18篇 |
2006年 | 10篇 |
2005年 | 9篇 |
2004年 | 3篇 |
2003年 | 5篇 |
2002年 | 2篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有891条查询结果,搜索用时 78 毫秒
471.
472.
Shakhawat Chowdhury Muhammad Al-Zahrani 《Environmental monitoring and assessment》2014,186(10):6127-6143
Change of water quality in dam reservoir and aquifer complicates safe drinking water supply. Few parameters are monitored to control water quality in these sources. Adequate knowledge on the correlation structure, interaction effect, trends and seasonal variability of these parameters is essential to control water quality. This study applied time series and multivariate analyses on 15 water quality parameters, collected from the King Fahd dam reservoir (L1) and aquifer (L2) in Saudi Arabia during April 2010 to February 2012. Moderate to strong correlations were observed between sulfate, hardness, fluoride, chloride, magnesium, conductivity, turbidity and total dissolved solids (TDS), while separate clusters were visible for TDS-chloride-magnesium-conductivity; fluoride-turbidity; chloride-hardness; ammonia-nitrate; and calcium-magnesium-hardness. Four major principal components explained 81.1 % and 83.2 % of the overall variances in L1 and L2, respectively. The factor analysis showed that 53 % and 67 % of the data were necessary to explain 81.3 % and 83.2 % of total variances for L1 and L2, respectively, indicating the possibility of data reduction. Possible degradation of water quality in these sources was highlighted, while such degradation may require enhanced treatment for producing drinking water in future. 相似文献
473.
474.
Muhammad Mahmood-ul-Hassan Vishandas Suthar Rizwan Ahmad Munazza Yousra 《Environmental monitoring and assessment》2017,189(11):591
The abilities of sorghum (Sorghum bicolor L.) and oat (Avena sativa L.) to take up heavy metals from soils amended with ethylenediaminetetraacetic acid (EDTA) were assessed under greenhouse conditions. Both plants were grown in two soils contaminated with heavy metals (Gujranwala—silty loam and Pacca—clay loam). The soils were treated with 0, 0.625, 1.25, and 2.5 mM EDTA kg?1 soil applied at both 45 and 60 days after sowing (DAS); the experiment was terminated at 75 DAS. Addition of EDTA significantly increased concentrations of Cd, Cr, and Pb in roots and shoots, and bio-concentration factors and phytoextraction rates were also increased. Post-harvest soil analysis showed that soluble fractions of metals were also increased significantly. The increase in Cd was ≈ 3-fold and Pb was ≈ 15-fold at the highest addition of EDTA in Gujranwala soil; in the Pacca soil, the increase was less. Similarly, other phytoremediation factors, such as metal translocation, bio-concentration factor, and phytoextraction, efficiency were also maximum when soils were treated with 2.5 mM EDTA kg?1 soil. The study demonstrated that sorghum was better than oat for phytoremediation. 相似文献
475.
Bilal Hussain Tayyaba Sultana Salma Sultana K. A. Al-Ghanim Shahreef Masood Muhammad Ali Shahid Mahboob 《Environmental monitoring and assessment》2017,189(3):115
This study investigates the potential of the comet and micronucleus assays of fish DNA as a means of screening the toxicity of aquatic environments. Catla catla and Cirrhinus mrigala collected from the River Chenab in Pakistan were used as a case study for the application of comet and micronucleus techniques. Comet and micronucleus assays were used to compare DNA damage in C. catla and C. mrigala collected from polluted areas of the River Chenab and farmed fish. Atomic absorption spectrophotometry showed an acute level of toxicity from Cd, Cu, Mn, Zn, Pb, Cr, Sn, and Hg in river water. Comet assay showed significant (p < 0.05) DNA damage in C. catla representing 17.33 ± 2.42, 11.53 ± 2.14, and 14.17% DNA in the comet tail, averaged from three sites of the polluted area of the river. Tail moment was observed as 10.06 ± 2.71, 3.11 ± 0.74, and 14.70 ± 1.89, while olive moment was 8.85 ± 1.84, 3.83 ± 0.76, and 7.11 ± 0.73, respectively. Highly significant (p < 0.01) damage was reported in C. mrigala as 37.29 ± 2.51, 34.96 ± 2.53, and 38.80 ± 2.42% DNA in comet tail, tail moment was 23.48 ± 3.90, 19.78 ± 4.26, and 14.30 ± 1.82, and olive moment was 16.22 ± 2.04, 13.83 ± 1.96, and10.99 ± 0.90. Significant (p < 0.05) differences were observed in genotoxicity between farmed and polluted area fish. Micronucleus assay showed a similar picture of significant difference in respect to single and double micronucleus induction: i.e., 23.20 ± 4.19 and 2.80 ± 1.07‰ in C. catla and 44.80 ± 3.73 and 06.20 ± 0.97‰, respectively, in C. mrigala. Nuclear abnormalities were found as 6.00 ± 0.84 and 09.60 ± 1.72/thousand cells, respectively, in both species. The results of this study suggest that these novel fish DNA damage assays can be used as an expedient toxicity screening for aquatic environments. 相似文献
476.
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
477.
Zakaria Man Nawshad Muhammad Ariyanti Sarwono Mohamad Azmi Bustam M. Vignesh Kumar Sikander Rafiq 《Journal of Polymers and the Environment》2011,19(3):726-731
In this paper cellulose nanocrystals were prepared by treating microcrystalline cellulose with 1-butyl-3-methylimidazolium
hydrogen sulphate ionic liquid. Cellulose nanocrystals, after separation from ionic liquid, were characterized by X-ray diffraction
(XRD), Fourier transform infrared (FTIR), Field emission scanning electron microscopy (FESEM) Transmission Electron Microscope
(TEM) and Thermogravimetric analysis. XRD results showed no changes in type of cellulose after the treatment with ionic liquid,
however, high crystallinity index was observed in the ionic liquid treated sample. Cellulose nanocrystals, having length around
50–300 nm and diameter around 14–22 nm were observed in the ionic liquid treated sample under FESEM and TEM, and similar patterns
of peaks as that of microcrystalline cellulose were observed for cellulose nanocrystals in the FTIR spectra. The thermal stability
of the cellulose nanocrystals was measured low as compare to microcrystalline cellulose. 相似文献
478.
Apolipophorin III, traditionally known for lipid transport in insects is fairly established as toxicity indicator against harmaline and tea saponin during this study. Apolipophorin III expressed in the hemolymph and midgut tissues of 3rd, 4th, 5th larval instars and pupae of Spodoptera exigua. Apolipophorin III presence was further confirmed by achieving its partial cDNA (Genbank accession no. FJ606822) of 448 bp. qRT PCR revealed that tea saponin resulted in significant reduction of gene expression in 3rd and 4th larval instars but increased in 5th instar as compared to control. Harmaline caused gradual increase of gene expression in 3rd, 4th and 5th instars after feeding on the treated diet. Fifth instar larvae synonymously resulted in the highest gene expressions against both the biochemicals. After the injection of harmaline and tea saponin abrupt increase in gene expression of 4th, 5th larval instar and pupae was observed as compared to control treatment. Transmission electron microscopy of midgut epithelium after being fed with harmaline and tea saponin depicted certain cytological changes. Harmaline treatment lead to cytoplasm vacuolization, mitochondrial disruption, spherocrystals with concentric layers, irregular nucleus and floating nuclei in cytoplasm. Tea saponin treatment resulted in denser cytoplasm, higher intracellular osmotic concentration and reduced complement of apical microvilli. Cells were found to have only a few mitochondria and glycogen deposits in comparison to control treatment. 相似文献
479.
Ahmad I Siddiqui H Akhtar MJ Khan MI Patil G Ashquin M Patel DK Arif JM 《Chemosphere》2011,83(4):455-460
In this in vitro study we investigated the toxic responses in hepatocytes treated with occupational dust to which workers are exposed in bone-based industrial units. The present study investigated the toxicity mechanism of bone-based occupational dust, from a particular industrial unit, on isolated rat hepatocytes. The hepatocytes were isolated by collagenase perfusion method and cell viability was determined by trypan blue exclusion and MTT [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay treated with occupational dust at 0.1-1.0 mgmL(-1), for 120 min. The cell viability decreased significantly in a concentration-dependent manner. Dust induced significant membrane damage measured by lactate dehydrogenase (LDH) and glutathione (GSH) release in culture media for 30-, 60- and 120 min treatment duration. The toxicity was found to be correlated with the induction of lipid peroxidation (LPO). In addition, nitric oxide (NO), and hydrogen peroxide (H(2)O(2)) generation by occupational dusts were also found to be time- and concentration-dependent. Over all the present study provides initial evidences for the toxic potential of occupational dust generated in bone-based industries and, therefore, the dust exposure to workers in unorganized industrial units should be controlled. 相似文献
480.
Anjum NA Ahmad I Válega M Pacheco M Figueira E Duarte AC Pereira E 《Environmental science and pollution research international》2011,19(7):2879-2888