全文获取类型
收费全文 | 2677篇 |
免费 | 102篇 |
国内免费 | 1012篇 |
专业分类
安全科学 | 202篇 |
废物处理 | 149篇 |
环保管理 | 211篇 |
综合类 | 1370篇 |
基础理论 | 482篇 |
污染及防治 | 1019篇 |
评价与监测 | 130篇 |
社会与环境 | 97篇 |
灾害及防治 | 131篇 |
出版年
2024年 | 3篇 |
2023年 | 48篇 |
2022年 | 134篇 |
2021年 | 107篇 |
2020年 | 89篇 |
2019年 | 96篇 |
2018年 | 85篇 |
2017年 | 119篇 |
2016年 | 144篇 |
2015年 | 174篇 |
2014年 | 230篇 |
2013年 | 282篇 |
2012年 | 204篇 |
2011年 | 223篇 |
2010年 | 209篇 |
2009年 | 176篇 |
2008年 | 170篇 |
2007年 | 136篇 |
2006年 | 158篇 |
2005年 | 110篇 |
2004年 | 96篇 |
2003年 | 88篇 |
2002年 | 93篇 |
2001年 | 119篇 |
2000年 | 77篇 |
1999年 | 76篇 |
1998年 | 75篇 |
1997年 | 61篇 |
1996年 | 45篇 |
1995年 | 40篇 |
1994年 | 31篇 |
1993年 | 23篇 |
1992年 | 19篇 |
1991年 | 8篇 |
1990年 | 15篇 |
1989年 | 3篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 5篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 2篇 |
排序方式: 共有3791条查询结果,搜索用时 15 毫秒
991.
排污总量管理的首要任务是确定区域污染物排放总量。针对我国的水污染监测管理系统的现状,本文提出了一种“系统特征值核定排污总量方法”。该法以城市或城市某排污区的排污干管(或河道)输出的污染物总量实测值为基本依据,对各种排污总量的申报统计值进行正误的识别、校核与调整,汇总综合评价结果,核定排污总量及各个分量。该方法既使核定的排污总量增加科学性和准确性,又减少了核定的工作量;即使缺乏排污申报数据,也能迅速可靠地掌握城市的排污总量。该方法的有效性已在济南市应用中得到证实 相似文献
992.
993.
Human PCDD/PCDF levels near a pentachlorophenol contamination site in Tainan, Taiwan 总被引:1,自引:0,他引:1
A pentachlorophenol (PCP) manufacturing plant in southern Taiwan discontinued production in 1989. The site of the abandoned plant was heavily contaminated by PCDD/PCDFs, impurities formed in the PCP production process. Serum samples collected from 27 residents living near the deserted plant were evaluated to determine whether this contamination had associated serum levels of PCDD/PCDFs in local residents. The average level of 17 tested congeners ranged from 556 to 5240 pg/g lipid (mean, 1670 pg/g lipid). The corresponding 2,3,7,8-TCDD toxicity equivalent quotient values calculated by international toxicity equivalent factors (I-TEFs) and those recommended by WHO (WHO-TEFs) were 47.2 pg I-TEQ/g lipid and 53.4 pg WHO-TEQ/g lipid, respectively. Levels in other parts of Taiwan typically range from 15 to 20 pg WHO-TEQ/g lipid; therefore, it is likely that the heavily contaminated plant site caused these unusually high serum levels. The average PCDD/PCDF levels of 29 fish-tissue and nine soil samples collected from the sea reservoir surrounding the abandoned PCP plant were also abnormally high: 8630 pg/g lipid (985 pg WHO-TEQ/g lipid) and 606000 pg/g-sample (922 pg WHO-TEQ/g-sample), respectively. Factor analysis indicated that the congener pattern of human serum samples collected from residents living near the abandoned PCP plant different from samples collected from other areas in Taiwan without known PCDD/PCDF pollution. Similar results were observed for the fish tissue and soil samples. The current study may have discovered a "hot spot" for elevated dioxin human exposure in Taiwan. The preliminary finding has raised a public health concern in the inspected area and requires further investigations to clarify the nature of the contamination and potential impact on the local environment and human health. 相似文献
994.
Han Xuesong Huettmann Falk Guo Yumin Mi Chunrong Wen Lijia 《Regional Environmental Change》2018,18(7):2173-2182
Regional Environmental Change - Ongoing global climate change greatly alters the distribution of species, and such impacts are even amplified on the Tibetan Plateau. The black-necked crane (Grus... 相似文献
995.
Yanxiu Guo Chaoyun Wang Xingren Pan Xiaofei Dong Wansong Zong 《Journal of environmental science and health. Part. B》2020,55(3):230-238
AbstractCiprofloxacin (CPFX) and enrofloxacin (ENFX), two of the most widely used fluoroquinolones (FQs), pose a great threat to humans and the ecosystem. In this study, the toxic mechanisms between the two FQs and trypsin were evaluated by means of multiple spectroscopic methods, as well as molecular docking. During the fluorescence investigations, both FQs quenched the intrinsic fluorescence of trypsin effectively, which was due to the formation of moderately strong complexes (mainly through van der Waals forces and hydrogen bonds). The binding of two FQs not only caused the conformational and micro-environmental changes of trypsin, but also changed its molecular activity; shown by the UV–Visible absorption spectroscopy, synchronous fluorescence spectroscopy, and functional tests. The established methods in this work can help to comprehensively understand the transport of FQs in the human body. 相似文献
996.
参考国家相关指南并结合南京市实际,以区级行政区为评价单元对南京市进行资源环境承载力评价。基于预警视角从资源、环境、生态等维度选取典型指标构建评价指标体系,分别进行针对资源、环境与生态的基础评价和针对农产品主产区的专项评价。采取"短板效应",结合基础、专项评价结果进行南京市资源环境承载力集成评价,为南京市资源环境承载力评价预警工作提供基础数据支撑,并从水资源、土地资源、大气环境、水环境、生态系统等方面进行超载因子识别与分析,提出相应的管控对策建议。 相似文献
997.
998.
Mi Jun Bian Jie Liu Yaru Guo Wenxia 《Environmental science and pollution research international》2020,27(30):37199-37209
Environmental Science and Pollution Research - The aim of this study was to explore the enterprises in the mining area, in the face of environmental pollution, to use relationship embedding to... 相似文献
999.
Guo ChengJun Xu YaLan Tian Zhong 《Environmental science and pollution research international》2020,27(30):37333-37346
Environmental Science and Pollution Research - Human civilization has reached an unprecedented height, but the industrialization of economic development also brings global warming, ozone depletion,... 相似文献
1000.
The extensive reclamation of marshland into cropland has tremendously impacted the ecological environment of the Sanjiang Plain in northeast China. To understand the impacts of marshland reclamation and restoration on soil properties, we investigated the labile organic carbon fractions and the soil enzyme activities in an undisturbed marshland, a cultivated marshland and three marshlands that had been restored for 3, 6 and 12?years. Soil samples collected from the different management systems at a depth of 0-20?cm in July 2009 were analyzed for soil organic carbon (SOC), dissolved organic carbon (DOC), microbial biomass carbon (MBC) and easily degradable organic carbon. In addition, the activities of the invertase, β-glucosidase, urease and acid phosphatase were determined. These enzymes are involved in C, N and P cycling, respectively. Long-term cultivation resulted in decreased SOC, DOC, MBC, microbial quotient and C (invertase, β-glucosidase) and N-transforming (urease) enzyme activities compared with undisturbed marshland. After marshland restoration, the MBC and DOC concentrations and the soil invertase, β-glucosidase and urease activities increased. Soil DOC and MBC concentrations are probably the main factors responsible for the different invertase, β-glucosidase and urease activities. In addition, marshland restoration caused a significant increase in the microbial quotient, which reflects enhanced efficiency of organic substrate use by microbial biomass. Our observations demonstrated that soil quality recovered following marshland restoration. DOC, MBC and invertase, β-glucosidase and urease activities were sensitive for discriminating soil ecosystems under the different types of land use. Thus, these parameters should be considered to be indicators for detecting changes in soil quality and environmental impacts in marshlands. 相似文献