首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1616篇
  免费   16篇
  国内免费   40篇
安全科学   22篇
废物处理   109篇
环保管理   156篇
综合类   139篇
基础理论   290篇
环境理论   2篇
污染及防治   545篇
评价与监测   300篇
社会与环境   105篇
灾害及防治   4篇
  2023年   59篇
  2022年   172篇
  2021年   116篇
  2020年   25篇
  2019年   46篇
  2018年   82篇
  2017年   88篇
  2016年   109篇
  2015年   45篇
  2014年   78篇
  2013年   176篇
  2012年   74篇
  2011年   89篇
  2010年   69篇
  2009年   58篇
  2008年   71篇
  2007年   54篇
  2006年   63篇
  2005年   34篇
  2004年   24篇
  2003年   20篇
  2002年   28篇
  2001年   8篇
  2000年   7篇
  1999年   5篇
  1998年   3篇
  1997年   2篇
  1996年   6篇
  1995年   2篇
  1994年   4篇
  1993年   3篇
  1992年   3篇
  1989年   2篇
  1988年   3篇
  1985年   2篇
  1984年   2篇
  1983年   4篇
  1982年   5篇
  1979年   2篇
  1969年   1篇
  1966年   1篇
  1965年   2篇
  1964年   2篇
  1962年   2篇
  1961年   4篇
  1958年   3篇
  1957年   3篇
  1956年   2篇
  1955年   4篇
  1953年   1篇
排序方式: 共有1672条查询结果,搜索用时 15 毫秒
871.
Environmental Science and Pollution Research - The world has never been prepared for global pandemics like the COVID-19, currently posing an immense threat to the public and consistent pressure on...  相似文献   
872.
In human-populated landscapes worldwide, domestic dogs (Canis lupus familiaris) are the most abundant terrestrial carnivore. Although dogs have been used for the protection of livestock from wild carnivores, they have also been implicated as predators of livestock. We used a combination of methods (field surveys, interview surveys, and data from secondary sources) to examine the patterns and factors driving livestock depredation by free-ranging dogs, as well as economic losses to local communities in a Trans-Himalayan agro-pastoralist landscape in India. Our results show that livestock abundance was a better predictor of depredation in the villages than local dog abundance. Dogs mainly killed small-bodied livestock and sheep were the most selected prey. Dogs were responsible for the majority of livestock losses, with losses being comparable to that by snow leopards. This high level of conflict may disrupt community benefits from conservation programs and potentially undermine the conservation efforts in the region through a range of cascading effects.  相似文献   
873.
The effects of three insecticides, dieldrin, dimethoate and permethrin, on the growth of a holotrichous ciliate, Tetrahymena pyriformis, were studied for 5 days. The ciliate was very sensitive to dieldrin and dimethoate. Both these insecticides produced approximately 81% and 84% inhibition of growth within two days. Dieldrin caused rounding of cells, while dimethoate induced cell lysis. Dimethoate also triggered a general mucocyst discharge. Of the three insecticides, permethrin was the least toxic and induced no morphological alterations.  相似文献   
874.
A simple multi-residue method based on modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) approach was established for the determination of 17 organochlorine (OC), 15 organophosphorous (OP) and 7 synthetic pyrethroid (SP) pesticides in an economically important medicinal plant of India, Senna (Cassia angustifolia), by gas chromatography coupled to electron capture and flame thermionic detectors (GC/ECD/FTD) and confirmation of residues was done on gas chromatograph coupled with mass spectrometry (GC-MS). The developed method was validated by testing the following parameters: linearity, limit of detection (LOD), limit of quantification (LOQ), matrix effect, accuracy–precision and measurement uncertainty; the validation study clearly demonstrated the suitability of the method for its intended application. All pesticides showed good linearity in the range 0.01–1.0 μg mL?1 for OCs and OPs and 0.05–2.5 μg mL?1 for SPs with correlation coefficients higher than 0.98. The method gave good recoveries for most of the pesticides (70–120%) with intra-day and inter-day precision < 20% in most of the cases. The limits of detection varied from 0.003 to 0.03 mg kg?1, and the LOQs were determined as 0.01-0.049 mg kg?1. The expanded uncertainties were <30%, which was distinctively less than a maximum default value of ±50%. The proposed method was successfully applied to determine pesticide residues in 12 commercial market samples obtained from different locations in India.  相似文献   
875.
Environmental Economics and Policy Studies - This study estimates health cost of salinity contamination in drinking water in the severe salinity affected three south-western districts of...  相似文献   
876.
The biodegradability of calcium stearate (CaSt) and cobalt stearate (CoSt) filled polypropylene (PP) films were investigated in this work. The PP films were prepared using melt blending technique followed by hot press moulding. On the basis of their tensile properties, the optimum amount of pro-oxidants was taken as 0.2 phr. Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used for the characterization of optimized films. Presence of pro-oxidant in the PP was confirmed by the FTIR studies. Addition of pro-oxidants in the films decreased the thermal stability as revealed by TGA analysis. Crystallinity of the pro-oxidant filled PP decreased with addition of pro-oxidants as showen by DSC. The maximum biodegradation of CaSt and CoSt containing PP films was showen 7.65 and 8.34%, respectively with 0.2 phr. Both the microbial test and plant growth test (on corn and tomato) indicated that biodegradation intermediates were non toxic.  相似文献   
877.
Environmental Science and Pollution Research - Heavy metals (HMs) have attracted global attention due to their toxicity, persistence, and accumulation in aquatic fish in the polluted water...  相似文献   
878.
879.
ABSTRACT

To understand the temporal variations of the physicochemical characteristics of the Bhagirathi-Hooghly River (BHR), three locations representing three districts of West Bengal were selected. The material fluxes from 34 drains during pre-monsoon season was quantified. The analysis of variance (ANOVA) revealed that no significant spatial variations were observed for the physicochemical parameters, whereas seasonal variations were significant. The mean discharge was found to be highest (247.2?×?103?m3?d?1) in the midstream drains. Highest mean concentrations of dissolved oxygen (DO) (7.35?mg?L?1) and nitrate (0.81?mg?L ?1) were observed during the post-monsoon season followed by the monsoon and pre-monsoon. According to the BIS, WHO and the European standard of water quality (pH, 6.5–8.5; Nitrate, 0–2.5?mg?L?1;DO, ≥5?mg?L?1), the results of the respective parameters revealed the BHR system is maintained at high to good water quality, meaning that the BHR system is slightly altered from its pristine environment. The mean concentrations of biological and chemical oxygen demands were found to be high during the monsoon season, revealing that a large quantity of refractory organic matter is transported to the eastern Bay of Bengal from the Ganges.  相似文献   
880.
Prevalence of keratinophilic fungi was observed in paddy field soil during different stages of cultivation viz., transplanting, tillering, milking and maturation. Out of total 76 soil samples, 65 soil samples were found to be positive for the keratinophilic fungi. Fourteen species belonging to a single genus Chrysosporium were isolated through out the cropping season. C. keratinophilum (17.1%) followed by C. tropicum (13.15%) were found to be the most dominating geophilic species. The highest percent distribution of keratinophilic fungi appeared during the milking stage (100%) of paddy cultivation, followed by the maturation stage (89.47%).  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号