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   407篇
  免费   2篇
  国内免费   1篇
安全科学   5篇
废物处理   21篇
环保管理   35篇
综合类   31篇
基础理论   119篇
污染及防治   101篇
评价与监测   79篇
社会与环境   15篇
灾害及防治   4篇
  2023年   8篇
  2022年   21篇
  2021年   17篇
  2020年   6篇
  2019年   7篇
  2018年   21篇
  2017年   14篇
  2016年   27篇
  2015年   6篇
  2014年   15篇
  2013年   24篇
  2012年   16篇
  2011年   17篇
  2010年   20篇
  2009年   18篇
  2008年   23篇
  2007年   13篇
  2006年   11篇
  2005年   31篇
  2004年   36篇
  2003年   37篇
  2002年   8篇
  2001年   3篇
  2000年   2篇
  1997年   1篇
  1995年   1篇
  1994年   1篇
  1978年   1篇
  1976年   1篇
  1964年   1篇
  1963年   1篇
  1957年   1篇
  1928年   1篇
排序方式: 共有410条查询结果,搜索用时 15 毫秒
1.
Environmental Science and Pollution Research - In this work, it was analyzed the behavior of three commercial activated carbons with different textural and chemical properties to adsorb...  相似文献   
2.
This study investigated some of the important physical (thickness swelling) and mechanical (modulus of rupture, modulus of elasticity and internal bond) properties of single-layer particleboard panels made from eucalyptus (Eucalyptus camaldulensis Dehn.), waste of grass clippings (Lolium perenne L.) and combinations of the two. The chemical properties (pH, holocelluse and alpha cellulose contents, and water, alcohol-benzene and 1% sodium hydroxide solubilities) of the raw materials were also determined. Panels with a 6:94 ratio of grass-to-eucalyptus particles had the required mechanical properties for interior fitments including furniture and general uses. Boards manufactured with 100% grass clippings exhibited the lowest quality. The overall panel properties improved with a lower percentage of grass clippings added. Based on initial results, it also appears that grass should compose no more than 13% to achieve acceptable panel properties for interior fitments and general uses.  相似文献   
3.
SCOPE: The detection and investigation of metal ions bound in strong complexes in natural waters is a difficult task, due to low concentration of the metal ions themselves, and also of the strong ligands, which, moreover, are often not of a well-defined composition. Here, a method is proposed for the investigation of the speciation of metal ions in natural waters. OBJECTIVE AND METHOD: It is based on the sorption of metal ions on strongly sorbing ion exchange resins, i.e. complexing resins. For this reason the method is called Resin Titration. It has been shown in previous investigations that the concentration of metal ion totally sorbed by a particular resin, and its reaction coefficient in the solution phase in the presence of the resin, can be determined from the sorption data using a simple relationship. Here, a data treatment (the Ruzic linearization method) is proposed for also determining the concentration of the ligands responsible for the complex in equilibrium with the resin. RESULTS: The method was applied to data obtained by Resin Titration of a freshwater and a seawater. Copper(II) and aluminium(III) were considered, using Chelex 100 as a titrant, due to its strong sorbing properties towards these metal ions. The results were: the total metal concentration in equilibrium with the resin, the side reaction coefficients, and the concentration of ligands. In all these cases the ligands forming very strong complexes were found to be at concentration lower than that of the metals. CONCLUSION: The Ruzic linearization method allows the determination of the concentration of the ligands forming very strong complexes in equilibrium with Chelex 100. The reaction coefficient was better determined by the calculation method previously proposed for RT. The ligands responsible for the strong complexes were found to be at low concentration, often lower than that of the metal ions considered. The metal in the original sample is partly bound to these ligands, since the complexes are very strong. Only a part of the metal is linked to weaker ligands, or free.  相似文献   
4.
Jonathan M. H. Green  Gemma R. Cranston  William J. Sutherland  Hannah R. Tranter  Sarah J. Bell  Tim G. Benton  Eva Blixt  Colm Bowe  Sarah Broadley  Andrew Brown  Chris Brown  Neil Burns  David Butler  Hannah Collins  Helen Crowley  Justin DeKoszmovszky  Les G. Firbank  Brett Fulford  Toby A. Gardner  Rosemary S. Hails  Sharla Halvorson  Michael Jack  Ben Kerrison  Lenny S. C. Koh  Steven C. Lang  Emily J. McKenzie  Pablo Monsivais  Timothy O’Riordan  Jeremy Osborn  Stephen Oswald  Emma Price Thomas  David Raffaelli  Belinda Reyers  Jagjit S. Srai  Bernardo B. N. Strassburg  David Webster  Ruth Welters  Gail Whiteman  James Wilsdon  Bhaskar Vira 《Sustainability Science》2017,12(2):319-331
Delivering access to sufficient food, energy and water resources to ensure human wellbeing is a major concern for governments worldwide. However, it is crucial to account for the ‘nexus’ of interactions between these natural resources and the consequent implications for human wellbeing. The private sector has a critical role in driving positive change towards more sustainable nexus management and could reap considerable benefits from collaboration with researchers to devise solutions to some of the foremost sustainability challenges of today. Yet opportunities are missed because the private sector is rarely involved in the formulation of deliverable research priorities. We convened senior research scientists and influential business leaders to collaboratively identify the top forty questions that, if answered, would best help companies understand and manage their food-energy-water-environment nexus dependencies and impacts. Codification of the top order nexus themes highlighted research priorities around development of pragmatic yet credible tools that allow businesses to incorporate nexus interactions into their decision-making; demonstration of the business case for more sustainable nexus management; identification of the most effective levers for behaviour change; and understanding incentives or circumstances that allow individuals and businesses to take a leadership stance. Greater investment in the complex but productive relations between the private sector and research community will create deeper and more meaningful collaboration and cooperation.  相似文献   
5.
Environmental Science and Pollution Research - The aim of this study was to investigate the protective efficacy of diosmin against subacute deltamethrin exposure. For this purpose, 40 male Wistar...  相似文献   
6.
Environmental Science and Pollution Research - Banana is one of the most important agricultural products of Ecuador. It relies on intensive monoculture cropping systems with a large volume of...  相似文献   
7.
8.
In order to understand the biodegradability of algal-derived organic matter, biodegradation experiments were conducted with 13C and 15N-labeled natural phytoplankton and periphytic algal populations in experimental conditions for 60 days. Qualitative changes in the dissolved organic matter were also determined using parallel factor analysis and the stable carbon isotopic composition of the hydrophobic dissolved organic matter through the experimental period. Although algal-derived organic matter is considered to be easily biodegradable, the initial amounts of total organic carbon newly produced by phytoplankton and periphytic algae remained approximately 16 and 44 % after 60 days, respectively, and about 22 and 43 % of newly produced particulate nitrogen remained. Further, the dissolved organic carbon derived from both algal populations increased significantly after 60 days. Although the dissolved organic matter gradually became refractory, the contributions of the algal-derived organic matter to the dissolved organic matter and hydrophobic dissolved organic matter increased. Our laboratory experimental results suggest that algal-derived organic matter produced by phytoplankton and periphytic algae could contribute significantly to the non-biodegradable organic matter through microbial transformations.  相似文献   
9.
The Taranto basin is a shallow water marine system in the South of Italy characterized by the presence of a lagoon environment together with a semi-enclosed bay connected to the Ionian Sea. This marine system experienced over the last few decades strong biochemical pollution and environmental degradation, and it is considered a hotspot study site for economic, ecological and scientific reasons. The aim of this study was to examine, on an annual temporal scale and with high spatial resolution, the main hydrodynamical processes and transport scales of the system by means of a 3D finite element numerical model application, adopting the most realistic forcing available. The model allowed us to assess the role played by baroclinic terms in the basin circulation, describing its estuarine nature. In particular, the main features of water circulation, salinity and temperature distribution, water renewal time and bottom stress were investigated. Our results allowed us to equate this system dynamic to that of a weakly stratified estuary, identifying the main driving sources of this mechanism. The vertical stratification over the whole year was proved to be stable, leading to a dual circulation flowing out on the surface, mainly through Porta Napoli channel, and inflowing on the bottom mainly through Navigabile channel. This process was responsible also for the renewal time faster on the bottom of the Mar Piccolo basin than the surface. Due to the great importance of the Taranto basin for what concerns sediment pollution, also the effect of currents in terms of bottom stress was investigated, leading to the conclusion that only in the inlets area the values of bottom stress can be high enough to cause erosion.  相似文献   
10.
The purpose this study was to improve operational planning and management of national parks in Turkey to balance conservation use and sustainable management. Souksu National Park (SNP) was chosen as the study area. The data were obtained from interviews of 182 visitor groups (in total, 819 people) and analyzed using correlation, factor, discriminant, and regression analyses. It was found that the most important factors affecting operational planning and management of SNP are (1) travel cost, (2) visitor welfare level, (3) intensity of use, (4) size of visitor group, (5) type of recreational demand. The main source of visitors to SNP is from a zone within a 0–90-km radius. This region comprised 53.85% of total visitors to the park. The capital of Turkey (Ankara) is the most important source of visitors from within this zone. The optimum activity mix in SNP is also determined. Picnicking, viewing the scenery, and nature walks or trekking comprised the main uses of the park. It is anticipated that these findings will help to improve operational planning and sustainable management of the national park and the environment.  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