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   464篇
  免费   12篇
  国内免费   1篇
安全科学   20篇
废物处理   29篇
环保管理   91篇
综合类   76篇
基础理论   95篇
污染及防治   113篇
评价与监测   30篇
社会与环境   16篇
灾害及防治   7篇
  2023年   9篇
  2022年   12篇
  2021年   12篇
  2020年   7篇
  2019年   10篇
  2018年   17篇
  2017年   19篇
  2016年   24篇
  2015年   17篇
  2014年   16篇
  2013年   44篇
  2012年   19篇
  2011年   31篇
  2010年   20篇
  2009年   11篇
  2008年   18篇
  2007年   28篇
  2006年   12篇
  2005年   14篇
  2004年   12篇
  2003年   12篇
  2002年   7篇
  2001年   11篇
  2000年   10篇
  1999年   10篇
  1998年   9篇
  1997年   5篇
  1996年   4篇
  1995年   4篇
  1994年   3篇
  1991年   3篇
  1990年   2篇
  1989年   5篇
  1988年   1篇
  1987年   2篇
  1986年   3篇
  1985年   4篇
  1984年   3篇
  1983年   2篇
  1982年   1篇
  1980年   1篇
  1979年   5篇
  1978年   1篇
  1977年   4篇
  1975年   5篇
  1974年   2篇
  1973年   1篇
  1972年   1篇
  1970年   2篇
  1964年   1篇
排序方式: 共有477条查询结果,搜索用时 312 毫秒
441.
In this work we present the experimental results of absorption rates and absorption capacity for the CO2 absorption by ammonia (NH3) aqueous solutions. Experiments are carried out in a thermoregulated Lewis-type cell reactor and are achieved in temperature and concentration ranges of 278–303 K and 2–5wt.% NH3 respectively. The obtained values for absorption kinetic rates and absorption capacity are compared with those available for alkanolamine solvents, commonly used to absorb CO2. In order to achieve this comparison, data available in studies about alkanolamine solvents at 303–333 K and 5–50wt.% for alkanolamines solutions were considered. Results show that CO2 absorption by NH3 is faster than the one carried out by MDEA, except for 2wt.% NH3 at 288 K. At 278 K and using aqueous solutions of 3wt.% NH3, the absorption rate is almost identical to the one reached with MDEA solvent. The highest absorption capacity, also compared with alkanolamine solution, is reached with aqueous solutions of 5wt.% NH3 at 278 K and 303 K.  相似文献   
442.
The present paper describes the development, performance and conclusions derived from three know-how and technology transfer projects to South American countries. The first project comprised a collaborative study by European and South American universities to find sustainable solutions for Chilean and Ecuadorian leather tanneries which had underachieving process performances. The second project consisted of investigations carried out in a Brazilian municipality to enhance its municipal solid waste management system. The final collaborative programme dealt with the initial identification, evaluation and registration of suspected contaminated sites in an industrial region of Chile. The detailed objectives, methods and procedures applied as well as the results and conclusions obtained in each of the three mentioned projects are presented, giving special attention to the organizational aspects and to the practical approach of each programme, concluding with their main advantages and disadvantages for identifying a set of qualitative and quantitative suggestions, and to establish transferable methods for future applications.  相似文献   
443.
444.
445.
446.
447.
448.
It has been suggested that pedestrians listening to personal music devices (PMD) are more likely to be involved in accidents than those not listening to PMDs. Though it has been demonstrated that pedestrians on cell phones exhibit less cautionary behaviour when street crossing ( [Hatfield and Murphy, 2007], [Nasar et al., 2008] and [Stavrinos et al., 2009]), little research has been conducted with PMD users. In the present study, cautionary behaviour (e.g., looking before crossing a road) was observed and recorded for pedestrians with or without PMDs. Amongst males, pedestrians listening to PMDs displayed more looking behaviour than those not listening to PMDs. Females showed no differences between the two conditions. Thus, unlike cell phones, PMDs do not decrease the cautionary behaviour of pedestrians. This suggests that cell phones and PMDs are two different types of distractions, and this needs to be taken into account when developing methods to prevent pedestrian accidents in the future.  相似文献   
449.
A study of a small sample of construction fatal accidents was used to pilot a potential method of analysis for the UK Health and Safety Executive (HSE) Construction Division. The work was conducted in the context of a Governmental Inquiry into construction fatalities in 2009, but has been developed further since. The sample of 26 accidents (28 fatalities) was drawn from the 211 fatal accidents in the years ending 2006–2008, to be broadly illustrative of the range of accident characteristics. The accidents were analysed on the basis of available inspectorate reports and structured interviews with the investigating inspectors. A standard method of classification on four levels was developed, based on the Human Factors Analysis and Classification System (HFACS) classification of errors and task level factors, with additional categories covering the organisational and regulatory/market levels of the system. The results showed a concentration of underlying factors associated with inadequacies in planning and risk assessment, competence assurance, hardware design, purchase and installation, and contracting strategy. These findings were partially validated by comparing them with another sample of 50 accidents analysed earlier by the HSE. This paper describes the development and testing of the investigation and classification method and how it is being further developed since the initial study. It also provides a summary of the findings relating to underlying causes.  相似文献   
450.
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