全文获取类型
收费全文 | 31524篇 |
免费 | 337篇 |
国内免费 | 249篇 |
专业分类
安全科学 | 884篇 |
废物处理 | 1169篇 |
环保管理 | 4243篇 |
综合类 | 5006篇 |
基础理论 | 8940篇 |
环境理论 | 23篇 |
污染及防治 | 8329篇 |
评价与监测 | 1930篇 |
社会与环境 | 1376篇 |
灾害及防治 | 210篇 |
出版年
2022年 | 250篇 |
2021年 | 270篇 |
2020年 | 198篇 |
2019年 | 249篇 |
2018年 | 467篇 |
2017年 | 459篇 |
2016年 | 656篇 |
2015年 | 545篇 |
2014年 | 767篇 |
2013年 | 2263篇 |
2012年 | 931篇 |
2011年 | 1374篇 |
2010年 | 1112篇 |
2009年 | 1111篇 |
2008年 | 1328篇 |
2007年 | 1422篇 |
2006年 | 1243篇 |
2005年 | 1088篇 |
2004年 | 1125篇 |
2003年 | 1060篇 |
2002年 | 1009篇 |
2001年 | 1290篇 |
2000年 | 877篇 |
1999年 | 575篇 |
1998年 | 439篇 |
1997年 | 450篇 |
1996年 | 450篇 |
1995年 | 491篇 |
1994年 | 450篇 |
1993年 | 401篇 |
1992年 | 419篇 |
1991年 | 382篇 |
1990年 | 383篇 |
1989年 | 417篇 |
1988年 | 351篇 |
1987年 | 306篇 |
1986年 | 281篇 |
1985年 | 311篇 |
1984年 | 295篇 |
1983年 | 328篇 |
1982年 | 327篇 |
1981年 | 275篇 |
1980年 | 243篇 |
1979年 | 273篇 |
1978年 | 231篇 |
1977年 | 198篇 |
1976年 | 200篇 |
1975年 | 195篇 |
1974年 | 173篇 |
1972年 | 199篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Rupert J. Baumgartner 《Journal of Cleaner Production》2011,19(8):783-786
Sustainable development has been intensely debated for more than twenty years, but real progress of our societies to become more sustainable is very slow. Therefore this special issue provides a forum for critical perspectives of Sustainable Development Research and Practice. The papers are grouped into three clusters: a. Sustainability Science, b. Economic Problems and c. Corporate Contributions to Sustainable Development.Although a single special issue cannot address the entire array of issues pertaining to progress of sustainability related research, the selected papers highlight special aspects of sustainability research either due to their theoretical contributions or because they report on valuable empirical evidence. The main goal of sustainability research should be to contribute to our understanding of sustainability problems and to develop and help to implement solutions to solve them. This can be described as the relevance of sustainability research. A precondition to gain relevance is the rigor of sustainability science: it has to be based on solid scientific principles and methods. Additionally it has to be regarded that Sustainable Development is dynamic and that it has both normative and practical aspects. It is concluded that sustainability science and practice should be based upon these four central aspects: rigor, relevance, normative aspects and dynamic 相似文献
992.
Ilton Curty Leal Junior Márcio de Almeida D'Agosto 《Journal of Cleaner Production》2011,19(2-3):229-240
Performance evaluation is important in managing freight transport. The transport of certain products, especially those that are hazardous, can have significant financial and socio-environmental impacts. This article presents an application of the modal choice method (MCM) to establish an order of priority among the alternatives considered to carry a determined hazardous product. After a research of the literature on the concepts and development of the proposed method, we consulted experts about their experiences and knowledge, to determine a set of relevant attributes for the evaluation process. We then applied this method to the specific case of the Brazilian bio-ethanol industry, to demonstrate the potential of using the MCM as a tool to support make decisions. We can conclude that highway transport, though the most often used, is not the best compared to trains or pipelines (or combinations of any of the three) from a socio-environmental standpoint. Alternatives with longer pipeline segments are the most suitable to replace the current practice in environmental terms. 相似文献
993.
J. García-Ten E. Monfort M.P. Gómez-Tena V. Sanz 《Journal of Cleaner Production》2011,19(9-10):1110-1116
The manufacture of traditional ceramic products (ceramic tiles, roof tiles, and bricks) is often associated with the emission of F, Cl, and S compounds during the firing stage. According to the literature, fluorine emissions can be reduced by adding CaCO3 to the raw materials mixture used in fabricating these products. However, data available to the authors indicate that this procedure, which has been successfully applied in manufacturing structural ceramics (roof tiles and bricks), is ineffective in ceramic tile manufacture and modifies tile end properties.This paper examines the possibility of reducing such emissions by applying coatings of alkaline-earth carbonates on to the ceramic tile bottom surface to retain the acid compounds emitted during tile firing. The effectiveness of MgCO3, CaCO3, SrCO3, and BaCO3 coatings for retaining these acid emissions was studied, using the evolved gas analysis (EGA) technique with a TG-DSC-FTIR-QM instrument.The SrCO3 coating was found to provide the greatest retention, showing that SO2 and HCl were retained more efficiently than HF. The presence of fluorides, chlorides, and sulphates of Ca, Sr, and Ba was verified in the respective fired coatings, confirming the existence of chemical reactions between the emitted acid compounds and the coating materials at high temperature. 相似文献
994.
995.
996.
997.
Objective
The objective of this study was to evaluate repeated patient handling injuries following a multi-factor ergonomic intervention program among health care workers.Methods
This was a quasi-experimental study which had an intervention group and a non-randomized control group. Data were collected from six hospitals in Saskatchewan, Canada from September 1, 2001 to December 1, 2006.Results
A total of 1,480 individuals who had a previous injury were eligible for the study. Medium and small size hospitals in the intervention group had significantly fewer repeated injuries than in the control group. Multivariate analysis showed that the intervention group had 38.1% lower odds of having repeated injury compared to the control group, after adjusting for hospital size.Conclusions
The work-related repeated injury after a multi-factor intervention program was reduced. The synergistic relationships between components of multi-factor intervention and applicability of injury prevention programs to different settings need to be further explored.Impact on Industry
Implementing a multi-factor program with the right equipment and training can lower the risk of injury among health care workers. 相似文献998.
Introduction: Occupational Health and Safety (OHS) stakeholders rarely factor the cost of workplace accidents into prevention spending decisions. The lack of consideration of this key information is related to the fact that the scientific literature has failed to provide OHS stakeholders with a cost-calculation tool that is both sufficiently accurate and does not require a data-collection stage ill-suited to the time constraints of workplace decision-makers. Method: This study reviews the recent literature to identify key elements that should foster the use of indirect-cost calculation methods by decision makers. Results: A “local” approach currently appears to be the best method for calculating indirect costs of workplace incidents or accidents in comparison to “bottom-up” or “top-down” approach. This paper discusses four criteria that this type of approach must satisfy to be compatible with the time constraints and accuracy demands of OHS stakeholders in organizations. In addition, four bases for the development of a new indirect cost estimation model are presented and discussed. Impact on industry: this study provides bases and criteria to help the development of indirect-cost calculation models better suited to workplace use than those currently available. 相似文献
999.
1000.
J.X. Wen A. HeidariS. Ferraris V.H.Y. Tam 《Journal of Loss Prevention in the Process Industries》2011,24(2):187-193
A modelling strategy has been developed for consequence analysis of medium and large scale gaseous detonation. The model is based on the solution of Euler equations with one-step chemistry. The Van Leer flux limited method which is a total variation diminishing scheme is used for shock capturing. Preliminary calculations were firstly conducted for small domains with fine grids which resolve the wave, relatively coarse grids which have less than 10 grids across the wave and coarse grids in which the minimum grid size is larger than the wave thickness to ensure that the reaction scheme has been properly tuned to capture the correct detonation pressure, temperature and velocity in the resolutions used in the different cases. The model was firstly tested against a medium scale detonation test in a shock tube with U-bends. Reasonably good agreement is achieved on detonation pressure and mean shock wave velocities at different measuring segments of the tube. Following the validation, the detonation of a hypothetical planar propane-air cloud is simulated. The predictions uncovered some interesting features of such large scale detonation phenomena which are of significance in the safety context, especially for accidental investigations. The findings from the present analysis are in line with the forensic evidence on damages in some historic accidents and challenges previous analysis of a major accident in which forensic evidence suggested localised detonation but was considered as the consequence of fire storms by the investigation team. 相似文献