全文获取类型
收费全文 | 1330篇 |
免费 | 60篇 |
国内免费 | 487篇 |
专业分类
安全科学 | 81篇 |
废物处理 | 81篇 |
环保管理 | 81篇 |
综合类 | 761篇 |
基础理论 | 233篇 |
污染及防治 | 518篇 |
评价与监测 | 46篇 |
社会与环境 | 45篇 |
灾害及防治 | 31篇 |
出版年
2023年 | 28篇 |
2022年 | 75篇 |
2021年 | 77篇 |
2020年 | 37篇 |
2019年 | 45篇 |
2018年 | 52篇 |
2017年 | 65篇 |
2016年 | 68篇 |
2015年 | 71篇 |
2014年 | 108篇 |
2013年 | 116篇 |
2012年 | 97篇 |
2011年 | 122篇 |
2010年 | 85篇 |
2009年 | 98篇 |
2008年 | 98篇 |
2007年 | 87篇 |
2006年 | 61篇 |
2005年 | 47篇 |
2004年 | 47篇 |
2003年 | 49篇 |
2002年 | 27篇 |
2001年 | 40篇 |
2000年 | 40篇 |
1999年 | 35篇 |
1998年 | 34篇 |
1997年 | 23篇 |
1996年 | 26篇 |
1995年 | 24篇 |
1994年 | 16篇 |
1993年 | 16篇 |
1992年 | 8篇 |
1991年 | 16篇 |
1990年 | 15篇 |
1989年 | 6篇 |
1988年 | 10篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1983年 | 1篇 |
1981年 | 1篇 |
排序方式: 共有1877条查询结果,搜索用时 234 毫秒
891.
Chengrun Wang Tingting Cheng Haitao Liu Fangyun Zhou Jifeng Zhang Min Zhang Xinya Liu Wenjun Shi Tong Cao 《环境科学学报(英文版)》2021,33(5):336-346
Selenium nanoparticles (Se NPs) are less toxic and more biocompatible than selenite or selenate. However, studies involving spraying with Se NPs for reducing accumulation of cadmium (Cd) and lead (Pb) in rice grains have been rarely reported as yet. Herein, indica rice seedlings cultivated in Cd+Pb-spiked paddy soils (denoted as positive control) were sprayed with Se NPs sols for four times from tillering to booting stage. Compared to positive control, 50–100 μmol/L Se NPs downregulated Cd transporters-related genes such as OsLCT1, OsHMA2 and OsCCX2 in leaves and OsLCT1, OsPCR1 and OsCCX2 genes in node I at filling stage. Meanwhile, Se-binding protein 1 was distinctly elevated, involving the repression of Cd and Pb transportation to rice grains. Se NPs also differentially improved RuBP carboxylase and chlorophylls especially some key genes and proteins involving photosynthetic system. Besides, 25–50 μmol/L Se NPs diminished reactive oxygen species overproduction from NADPH oxidases whereas boosted glutathione peroxidase, reducing protein carbonylation in rice seedlings. However, the antioxidant isozymes and oxidatively modified proteins were slightly rebounded at 100 μmol/L. Se contents were noticeably elevated and confirmed to exist as selenomethionine in the rice grains following all the treatments by Se NPs. Thus, the optimal dosage of Se NPs for foliar application is 50 μmol/L, which significantly decreased Cd accumulation, improved photosynthesis and Se enrichment whereas caused no distinct reduction of Pb in the grains. Thus, an appropriate dosage of Se NPs can be conducted to decrease Cd accumulation, improve photosynthesis, and organic Se contents in rice grains. 相似文献
892.
通过对现行空间规划法律规范的体系性检视,发现由于立法策略、部门立法以及规划立法依附性等原因,其存在顶层立法付之阙如、外部结构冗杂扁平、内部规范碎片冲突等问题。遵循领域法、发展法以及体系化逻辑,国土空间规划立法应以现实问题与治理现代化为导向,在突破部门法壁垒的同时注重法制发展的接续性,力求实现国土空间规划法律体系的形式协调与价值融贯。构建国土空间规划法律体系,对内应确立国土空间规划法的基本法地位并辅之以配套立法,对外应注重与国土空间开发保护法等相关立法、国土空间政策与技术标准的衔接,最终构架起一个主轴明确、层次严密、差序有别的圆锥状国土空间规划法律体系。 相似文献
893.
Zhou Jiacheng Shen Qicheng Yang Jie Tariq Muhammad Sun Wei Cao Limei Yang Ji 《Environmental science and pollution research international》2021,28(46):65487-65498
Environmental Science and Pollution Research - Co3O4 is a promising Hg0 removal catalyst for industrial application. Operating temperature and low sulfur resistance are two of the main problems... 相似文献
894.
The effects of chlorfenapyr nano preparation on mice were examined. The animals were administered with different doses of 4.84, 9.68, or 19.36?mg?kg?1 of chlorfenapyr common preparation or nano preparation intraperitoneally (IP). Micronucleus (MN) test and comet assay (CA) experiments revealed that at the same dose, similar DNA damage in the peripheral blood lymphocytes of the mouse and chromosome damage in bone marrow cells of the mouse occurred with chlorfenapyr nano preparation; however, the severity of these effects was less than that found in common preparation. It is noteworthy that there were no differences in apoptotic ratio and live cell percentage in the liver cells of the mouse between these two pesticide formulations using flow cytometry. Data indicate that chlorfenapyr nanoformulation is less toxic to mouse cells than the common formulation. 相似文献
895.
Yiqun Cao Qingxin Ma Biwu Chu Hong He 《Frontiers of Environmental Science & Engineering》2023,17(4):48
896.
Cao Qian Wu Jianguo Yu Deyong Wang Renqing Qiao Jianmin 《Regional Environmental Change》2020,20(2):1-15
Regional Environmental Change - Pacific Island Countries, despite significant variation in levels of exposure and internal adaptive capacities, are often portrayed homogenously as the world’s... 相似文献
897.
Luyu Ding Wei Cao Zhengxiang Shi Baoming Li Guoqiang Zhang 《Journal of the Air & Waste Management Association (1995)》2016,66(7):715-725
To investigate the impacts of major factors on carbon loss via gaseous emissions, carbon dioxide (CO2) and methane (CH4) emissions from the ground of open dairy lots were tested by a scale model experiment at various air temperatures (15, 25, and 35 °C), surface velocities (0.4, 0.7, 1.0, and 1.2 m sec?1), and floor types (unpaved soil floor and brick-paved floor) in controlled laboratory conditions using the wind tunnel method. Generally, CO2 and CH4 emissions were significantly enhanced with the increase of air temperature and velocity (P < 0.05). Floor type had different effects on the CO2 and CH4 emissions, which were also affected by air temperature and soil characteristics of the floor. Although different patterns were observed on CH4 emission from the soil and brick floors at different air temperature-velocity combinations, statistical analysis showed no significant difference in CH4 emissions from different floors (P > 0.05). For CO2, similar emissions were found from the soil and brick floors at 15 and 25 °C, whereas higher rates were detected from the brick floor at 35 °C (P < 0.05). Results showed that CH4 emission from the scale model was exponentially related to CO2 flux, which might be helpful in CH4 emission estimation from manure management.Implications: Gaseous emissions from the open lots are largely dependent on outdoor climate, floor systems, and management practices, which are quite different from those indoors. This study assessed the effects of floor types and air velocities on CO2 and CH4 emissions from the open dairy lots at various temperatures by a wind tunnel. It provided some valuable information for decision-making and further studies on gaseous emissions from open lots. 相似文献
898.
Xu Hongliang Song Wenjuan Cao Wenbo Shao Gang Lu Hongxia Yang Daoyuan Chen Deliang Zhang Rui 《Journal of Material Cycles and Waste Management》2017,19(3):1270-1278
Journal of Material Cycles and Waste Management - Coal gangue, an industrial solid waste discarded from coal mining and processing, was used as the sole raw material to prepare brick. The coal... 相似文献
899.
Wang Fei Li Chunfang Wang Jining Cao Wentao Wu Quanyuan 《Environmental science and pollution research international》2017,24(20):16883-16892
Environmental Science and Pollution Research - Since sewage irrigation can markedly disturb the status of heavy metals in soils, a convenient and accurate technique for heavy metal concentration... 相似文献
900.
基于多元统计的水质动态评价模型研究与应用 总被引:1,自引:0,他引:1
给出一种基于多元统计的水质动态评价模型方法,该模型方法以全局主成分分析(GPCA)方法为主,以动态聚类分析、判别分析为辅助方法。再以湟水流域水质断面为例,根据有机污染、无机污染和综合污染等3个方面对这些水质断面1998—2005年水质污染状态进行定量评价和动态分析。研究结果表明:湟水流域水质断面有机污染较为严重,以上3个方面的污染状态逐年严重,综合污染指数均值从1998年的1.63605上升到2005年的2.38624,2001年以后有加速恶化的迹象。 相似文献