全文获取类型
收费全文 | 585篇 |
免费 | 24篇 |
国内免费 | 46篇 |
专业分类
安全科学 | 42篇 |
废物处理 | 18篇 |
环保管理 | 144篇 |
综合类 | 260篇 |
基础理论 | 69篇 |
环境理论 | 5篇 |
污染及防治 | 54篇 |
评价与监测 | 19篇 |
社会与环境 | 39篇 |
灾害及防治 | 5篇 |
出版年
2024年 | 2篇 |
2023年 | 9篇 |
2022年 | 9篇 |
2021年 | 12篇 |
2020年 | 11篇 |
2019年 | 23篇 |
2018年 | 18篇 |
2017年 | 25篇 |
2016年 | 38篇 |
2015年 | 25篇 |
2014年 | 24篇 |
2013年 | 45篇 |
2012年 | 41篇 |
2011年 | 51篇 |
2010年 | 21篇 |
2009年 | 34篇 |
2008年 | 32篇 |
2007年 | 25篇 |
2006年 | 48篇 |
2005年 | 16篇 |
2004年 | 12篇 |
2003年 | 25篇 |
2002年 | 30篇 |
2001年 | 17篇 |
2000年 | 17篇 |
1999年 | 13篇 |
1998年 | 10篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1980年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有655条查询结果,搜索用时 328 毫秒
291.
292.
阐述了高强度埋纱绿色包装袋纸是纸/塑复合或塑/塑复膜的污染环境包装材料的替代产品,生产流水线由5项专利技术为基础构成,生产原料来源充足,体现资源循环利用,生产企业经济效益显著,产品具有撕裂度,抗张强度高,抗水防潮,耐热,牢固度好,破包率低,指出产品可为国家节约大批木材,对保护森林资源贡献巨大,产品生产过程中不对环境造成污染。 相似文献
293.
Smith CB Anderson JE Fischer RL Webb SR 《Environmental pollution (Barking, Essex : 1987)》2002,120(3):517-520
Green fluorescent protein (GFP) was first isolated in the early 1970s for experimental use from coelenterates or the Pacific jellyfish. Aequorea victoria (Morin and Hastings, 1971). GFP has since become a favored biomarker in the photophysical analysis of molecular and cell biology because of its strong intrinsic visible fluorescence and the feasibility of fusing it to other proteins without affecting their normal functions (Creemers et al., 2000). Here we report using Bacillus subtilis expressing GFP to evaluate the influence of different environmental pH conditions on GFP fluorescence. Emission acquisitions were configured to excite at 471 nm and detect at an emission from 490 to 650 nm at 1-nm increments. Fluorescence intensity was significantly better at pH 7 (4.2 x 105 cps; P-value < 0.01) than at acid or alkaline conditions. GFP is a good biomarker for environments near netural conditions: however, GFP may be unsuitable where soils or waters are below or above pH 7 because of loss in fluorescence intensity. Alternative fluorescent markers and delivery systems must be examined in different environments to optimize responses from bioreporter molecules. 相似文献
294.
Green liquor dregs is the biggest waste fraction at sulphate pulp mills. It is commonly landfilled. Here we demonstrate that
the utilization of green liquor dregs as a neutralizing agent for acidic wastewaters is a potential alternative and an environmentally
friendly method in contrast to its landfill disposal. The liming effect value of 39.6% for green liquor dregs, expressed as
Ca equivalent, is similar to the liming effect value of 38% of a commercial limestone product. In addition, the pH value of
10.7 indicates a strong liming effect. 相似文献
295.
为探讨KMnO4用作阴极电子受体对牛粪长期发酵产电性能的影响,构建了以牛粪为主要底物的双室微生物燃料电池(Microbial fuel cell,MFC),考察了50,200,800mg/L KMnO4时牛粪MFC开路电势、输出电压、功率密度、有机底物变化及降解情况.结果表明:当KMnO4为800mg/L(MFC-800)时产生的开路电势和输出电压最高,分别达到1148mV和234mV,最大功率密度达177mW/m3,库伦效率和净产能最大,分别为18%和19.5MJ/t;电池运行203d后,MFC-800的COD去除率最高,达68.1%;在电池运行过程中,MFC-800的VFA浓度增加了3.5倍,达388mmol/L;pH值从7.25下降到5.71下降了1.54;产电结束后,阳极发酵固态剩余物的成分符合《有机肥料》(NY525-2012)标准,可用于有机肥料生产. 相似文献
296.
选取IPCC碳排放核算方法并基于能源统计数据,核算了我国大陆30个省市的能源消耗碳排放量,利用纠正后的DMSP/OLS夜间灯光数据与相应空间单元的碳排放量进行回归分析,反演出1km×1km栅格的电力消耗碳排放量并分析其在地级市尺度上的时空变化.核算出2005年、2010年和2013年能源消耗排放总量分别为57.02,82.28和93.26亿t,其中电力碳排放量分别为23.03,35.62和42.07亿t.结果表明:校正后的DMSP/OLS夜间灯光数据能更好地估算碳排放,其DN总值与统计的省级能源消耗排放量、电力消耗排放量均存在较强的相关关系;整体而言,发达地区能源消耗排放量大但强度比较低. 相似文献
297.
We report that green algae in lakes and rivers can serve as precursors of halobenzoquinone(HBQ) disinfection byproducts(DBPs) produced during chlorination. Chlorination of a common green alga, Chlorella vulgaris, produced 2,6-dichloro-1,4-benzoquinone(2,6-DCBQ), the most prevalent HBQ DBP in disinfected water. Under varying p H conditions(p H 6.0–9.0), 2,6-DCBQ formation ranged from 0.3 to 2.1 μg/mg C with maximum formation at p H 8.0. To evaluate the contribution of organic components of C. vulgaris to 2,6-DCBQ formation, we separated the organics into two fractions, the protein-rich fraction of intracellular organic matter(IOM) and the polysaccharide-laden fraction of extracellular organic matter(EOM). Chlorination of IOM and EOM produced 1.4 μg/mg C and 0.7 μg/mg C of 2,6-DCBQ, respectively. The IOM generated a two-fold higher 2,6-DCBQ formation potential than the EOM fraction, suggesting that proteins are potent 2,6-DCBQ precursors. This was confirmed by the chlorination of proteins extracted from C. vulgaris: the amount of 2,6-DCBQ produced is linearly correlated with the concentration of total algal protein(R2= 0.98). These results support that proteins are the primary precursors of 2,6-DCBQ in algae, and control of green algal bloom outbreaks in source waters is important for management of HBQ DBPs. 相似文献
298.
2006—2015年中国电力碳足迹及其生态压力分析 总被引:1,自引:0,他引:1
电力行业是我国节能减排的主力军.本文根据电力来源多样性特征,采用IPCC计算方法,结合净初级生产力模型,定量分析了中国2006-2015年电力消费碳足迹及其生态压力的变化,并将电力碳足迹生态压力与人均GDP进行脱钩分析.结果表明,2006-2015年,电力消费碳排放量经历了先升后降两个阶段,其中,2006-2013年,碳排放量稳步上升,2013年后开始逐渐下降,电力碳足迹生态压力与人均GDP之间主要呈弱脱钩关系,但在2013-2015年,开始出现强脱钩状态.可见在国家″十二五″政策引导下,推动经济结构转型调整,促进电力产业节能减排,已获得显著成效,但仍需继续努力,缓解电力消费过程给生态环境带来的压力. 相似文献
299.
提出了绿色财富核算的概念,对绿色财富核算的内容和范围进行了界定;在前人研究的基础上,对绿色财富各组成内容的核算方法进行了探索研究。以湖北省神农架林区为例,首次在国家区域层面对绿色财富进行了核算。研究结果表明:2004年神农架林区绿色财富总值为236.13亿元,自然资产总价值为46.91亿元,占整个绿色财富的比例为19.86%;生态服务功能总价值为189.23亿元,占整个绿色财富的比例为80.14%,生态服务功能价值高于自然资产价值约60个百分点;同时,神农架林区的绿色财富要远远高于物质财富,绿色财富大约是物质财富的4.6倍,高出物质财富约185亿元,绿色财富在总国民财富中发挥着重要作用。论文的研究方法和结论为国家自然保护区的生态补偿、财政转移支付、自然资源管理等政策的制定提供了定量分析基础。 相似文献
300.
Brian Baily Alastair Pearson Peter Collier Dominic Fontana 《Journal of Coastal Conservation》2002,8(1):77-86
This paper discusses a research project dealing with the mapping of the intertidal vegetation of several harbours along the
southern coastline of England. It describes in detail the methods used to map the vegetation and gives examples of the results
from these studies. This paper then goes on to explain how these results are applied by the Environment Agency of England
and Wales to improve water quality in the harbours. This type of vegetation mapping is useful in monitoring the development
of the intertidal species includingSpartina, Zostera and of particular importance to this study the green algaeUlva andEnteromorpha. The work was undertaken with funding from the Environment Agency and at present has taken place over a four year period.
The data collected will be used by the Environment Agency to assess macro-algae covervalues for the intertidal area of the
harbours concerned. This forms part of the Agency's commitment to the EU Nitrates Directive and the Urban Waste Water Treatment
Directive. Some of the species mapped act as suitable indicators of water quality and are symptoms of entrophication. Other
species are of interest for nature conservation and were recorded to provide a record for longer-term trends in vegetation
patterns within the harbour. This paper aims to provide readers with an understanding of the techniques involved as well as
an evaluation of the methodology. 相似文献