全文获取类型
收费全文 | 2677篇 |
免费 | 189篇 |
国内免费 | 352篇 |
专业分类
安全科学 | 198篇 |
废物处理 | 127篇 |
环保管理 | 1148篇 |
综合类 | 1008篇 |
基础理论 | 294篇 |
环境理论 | 4篇 |
污染及防治 | 151篇 |
评价与监测 | 83篇 |
社会与环境 | 164篇 |
灾害及防治 | 41篇 |
出版年
2024年 | 12篇 |
2023年 | 37篇 |
2022年 | 55篇 |
2021年 | 81篇 |
2020年 | 85篇 |
2019年 | 66篇 |
2018年 | 50篇 |
2017年 | 71篇 |
2016年 | 84篇 |
2015年 | 65篇 |
2014年 | 74篇 |
2013年 | 120篇 |
2012年 | 127篇 |
2011年 | 107篇 |
2010年 | 97篇 |
2009年 | 91篇 |
2008年 | 102篇 |
2007年 | 96篇 |
2006年 | 90篇 |
2005年 | 81篇 |
2004年 | 94篇 |
2003年 | 118篇 |
2002年 | 193篇 |
2001年 | 176篇 |
2000年 | 199篇 |
1999年 | 153篇 |
1998年 | 116篇 |
1997年 | 88篇 |
1996年 | 227篇 |
1995年 | 60篇 |
1994年 | 22篇 |
1993年 | 15篇 |
1992年 | 7篇 |
1991年 | 6篇 |
1990年 | 5篇 |
1989年 | 9篇 |
1988年 | 4篇 |
1986年 | 1篇 |
1985年 | 22篇 |
1984年 | 38篇 |
1983年 | 35篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 7篇 |
1978年 | 5篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1972年 | 1篇 |
1971年 | 15篇 |
1967年 | 1篇 |
排序方式: 共有3218条查询结果,搜索用时 329 毫秒
121.
122.
Nugraha E. Suyatma Alain Copinet Lan Tighzert Veronique Coma 《Journal of Polymers and the Environment》2004,12(1):1-6
Biodegradable film blends of chitosan with poly(lactic acid) (PLA) were prepared by solution mixing and film casting. The main goal of these blends is to improve the water vapor barrier of chitosan by blending it with a hydrophobic biodegradable polymer from renewable resources. Mechanical properties of obtained films were assessed by tensile test. Thermal properties, water barrier properties, and water sensitivity were studied by differential scanning calorimeter analysis, water vapor permeability measurements, and surface-angle contact tests, respectively. The incorporation of PLA to chitosan improved the water barrier properties and decreased the water sensitivity of chitosan film. However, the tensile strength and elastic modulus of chitosan decreased with the addition of PLA. Mechanical and thermal properties revealed that chitosan and PLA blends are incompatible, consistent with the results of Fourier transform infrared (FTIR) analysis that showed the absence of specific interaction between chitosan and PLA. 相似文献
123.
Hao-Jan Hsing Fang-Kuo Wang Pen-Chi Chiang Wan-Fa Yang 《Resources, Conservation and Recycling》2004,40(4):42
More than 50,000 tons of hazardous waste are imported and exported worldwide each year. Over 50% of hazardous waste is exported to Southeast Asia, of which leather waste is the major component. The exportation quantities of hazardous waste to Organization of Economic Cooperation and Development (OECD) countries are decreasing while they are on the increase to non-OECD countries. Some of these wastes are intended for recycling purposes but the usage of some others is not stipulated. The hazardous waste importation quantity kept fairly steady from 1997 to 2000, of which ash or residues containing copper or copper compounds were the major component. Under existing regulations and measures, the transboundary movement of hazardous waste cannot be effectively controlled and monitored. In order to ensure environmentally sound hazardous waste management, EPA-Taiwan revised the Waste Disposal Act in 2001 and cooperated with the Industrial Development Bureau (IDB) to promote industrial waste reduction and recycling projects. Strategies were proposed based on evaluation according to the 3Es Principles and the site investigation in this study. 相似文献
124.
史立杰 《中国环境管理干部学院学报》2005,15(3):74-76
工业兴市是一个区域经济发展的必然选择,而建设一个绿色生态化工城又是葫芦岛市发展的必由之路.以人为本、科技领先、加强环境保护、推进循环经济发展,以提高城市品位,力争全面达到创建"国家环保模范城"标准,营造一个最适宜人类居住的绿色生态城市. 相似文献
125.
论我国绿色会计理论体系的构建 总被引:2,自引:0,他引:2
郭春燕 《中国环境管理干部学院学报》2005,15(3):125-128
运用系统论的思想和方法,对我国绿色会计理论体系的基本框架进行了构建,提出绿色会计理论体系作为系统是由若干个要素或子系统组成的有机整体.这些子系统之间既具有一定的联系,又都有其特定的功能作用,都要受到一定的社会、经济和生态资源等外部环境因素的影响.绿色会计理论体系的组成要素包括绿色会计的理论基础、职能、目标、对象、假设、原则、确认、计量和报表等内容.在此理论的基础上,提出了一些具体实施的可行性建议. 相似文献
126.
Recycling operations have become one of the primary strategies for waste management, worldwide. Especially, recycling operations are viewed as among the most effective techniques for reducing the amount of municipal solid waste disposed at landfill sites. Botswana's environmental policy on recycling stipulates, among others, that all waste management authorities should provide information on the classification and quantities of controlled waste targeted for recycling. This paper, therefore, examines the extent to which recycling operations in Botswana have either been conducted in compliance with or in violation of some major environmental requirements as enunciated on statutory guidelines. Compatibility between environmental policies on recycling and actual practice is evaluated focusing on two companies (Dumatau trading and Botswana Tissue) involved in recycling operation. Data from the two companies is complemented by one collected from the Gaborone landfill site. Finally, this study discusses on the role played by various stakeholders in policy formulation and implementation with particular emphasis being placed on a select number of non-governmental organisations (NGO). 相似文献
127.
Conservation decision makers commonly use project‐scoring metrics that are inconsistent with theory on optimal ranking of projects. As a result, there may often be a loss of environmental benefits. We estimated the magnitudes of these losses for various metrics that deviate from theory in ways that are common in practice. These metrics included cases where relevant variables were omitted from the benefits metric, project costs were omitted, and benefits were calculated using a faulty functional form. We estimated distributions of parameters from 129 environmental projects from Australia, New Zealand, and Italy for which detailed analyses had been completed previously. The cost of using poor prioritization metrics (in terms of lost environmental values) was often high—up to 80% in the scenarios we examined. The cost in percentage terms was greater when the budget was smaller. The most costly errors were omitting information about environmental values (up to 31% loss of environmental values), omitting project costs (up to 35% loss), omitting the effectiveness of management actions (up to 9% loss), and using a weighted‐additive decision metric for variables that should be multiplied (up to 23% loss). The latter 3 are errors that occur commonly in real‐world decision metrics, in combination often reducing potential benefits from conservation investments by 30–50%. Uncertainty about parameter values also reduced the benefits from investments in conservation projects but often not by as much as faulty prioritization metrics. 相似文献
128.
Ian Babelon Alexander Ståhle Berit Balfors 《Journal of Environmental Planning and Management》2017,60(8):1366-1390
Web-based Public Participation Geographic Information Systems (PPGIS) are increasingly used for surveying place values and informing municipal planning in contexts of urban densification. However, research is lagging behind the rapid deployment of PPGIS applications. Some of the main opportunities and challenges for the uptake and implementation of web-based PPGIS are derived from a literature review and two case studies dealing with municipal planning for urban densification in the Stockholm region, Sweden. A simple clustering analysis identified three interconnected themes that together determine the performance of PPGIS: (i) tool design and affordances; (ii) organisational capacity; and (iii) governance. The results of the case studies augment existing literature regarding the connections between the different socio-technical dimensions for the design, implementation and evaluation of PPGIS applications in municipal planning. A cyborg approach to PPGIS is then proposed to improve the theoretical basis for addressing these dimensions together. 相似文献
129.
In Latin America and the Caribbean, river restoration projects are increasing, but many lack strategic planning and monitoring. We tested the applicability of a rapid visual social–ecological stream assessment method for restoration planning, complemented by a citizen survey on perceptions and uses of blue and green infrastructure. We applied the method at three urban streams in Jarabacoa (Dominican Republic) to identify and prioritize preferred areas for nature-based solutions. The method provides spatially explicit information for strategic river restoration planning, and its efficiency makes it suitable for use in data-poor contexts. It identifies well-preserved, moderately altered, and critically impaired areas regarding their hydromorphological and socio-cultural conditions, as well as demands on green and blue infrastructure. The transferability of the method can be improved by defining reference states for assessing the hydromorphology of tropical rivers, refining socio-cultural parameters to better address river services and widespread urban challenges, and balancing trade-offs between ecological and social restoration goals.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01565-3. 相似文献
130.
重金属共存严重抑制了微生物降解染料的效率,本研究拟采用EDTA螯合Cr提高Burkholderia cepacia C09G降解复合污染中孔雀绿的效率.实验结果表明,0.1 mmol·L~(-1)孔雀绿单独存在条件下,24 h的生物降解率达到96.2%;然而,在0.5 mmol·L~(-1)Cr(VI)共存条件下,60 h的降解率仅为6.7%.当加入0.5 mmol·L~(-1)EDTA螯合剂后,60 h时孔雀绿的降解率提高到18.8%.当EDTA浓度为0.5 mmol·L~(-1)时,最佳螯合Cr(VI)的浓度为0.7 mmol·L~(-1),此时,60 h后孔雀绿的降解率达到35.3%,对Cr(VI)的吸附率为24.6%.此外,通过EDS、SEM、XPS分析证明,EDTA可以减小Cr(VI)的毒性,Burkholderia cepacia C09G可将吸附的Cr(VI)还原为Cr(III). 相似文献