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   234篇
  免费   5篇
  国内免费   15篇
安全科学   29篇
废物处理   2篇
环保管理   75篇
综合类   45篇
基础理论   46篇
环境理论   1篇
污染及防治   25篇
评价与监测   7篇
社会与环境   17篇
灾害及防治   7篇
  2023年   3篇
  2022年   3篇
  2021年   1篇
  2020年   3篇
  2019年   7篇
  2018年   9篇
  2017年   5篇
  2016年   12篇
  2015年   7篇
  2014年   8篇
  2013年   30篇
  2012年   3篇
  2011年   12篇
  2010年   3篇
  2009年   12篇
  2008年   6篇
  2007年   13篇
  2006年   14篇
  2005年   5篇
  2004年   4篇
  2003年   5篇
  2002年   5篇
  2001年   11篇
  2000年   6篇
  1999年   7篇
  1998年   2篇
  1997年   5篇
  1996年   3篇
  1995年   4篇
  1994年   3篇
  1993年   5篇
  1992年   4篇
  1991年   3篇
  1990年   2篇
  1989年   3篇
  1987年   1篇
  1986年   1篇
  1985年   4篇
  1984年   1篇
  1983年   2篇
  1981年   4篇
  1980年   3篇
  1978年   2篇
  1977年   2篇
  1976年   1篇
  1975年   1篇
  1973年   1篇
  1972年   1篇
  1971年   2篇
排序方式: 共有254条查询结果,搜索用时 15 毫秒
91.
This review aimed to systematically summarize the epidemiological literature on the cardiorespiratory effects of PM2.5 published during the 13th Five-Year Plan period (2016–2020) in China. Original articles published between January 1, 2016 and June 30, 2021 were searched in PubMed, Web of Science, the China National Knowledge Internet Database and Wanfang Database. Random- or fixed-effects models were used to pool effect estimates where appropriate. Of 8558 records identified, 145 met the full eligibility criteria. A 10 µg/m³ increase in short-term PM2.5 exposure was significantly associated with increases of 0.70%, 0.86%, 0.38% and 0.96% in cardiovascular mortality, respiratory mortality, cardiovascular morbidity, and respiratory morbidity, respectively. The specific diseases with significant associations included stroke, ischemic heart disease, heart failure, arrhythmia, chronic obstructive pulmonary disease, pneumonia and allergic rhinitis. The pooled estimates per 10 µg/m³ increase in long-term PM2.5 exposure were 15.1%, 11.9% and 21.0% increases in cardiovascular, stroke and lung cancer mortality, and 17.4%, 11.0% and 4.88% increases in cardiovascular, hypertension and lung cancer incidence respectively. Adverse changes in blood pressure, heart rate variability, systemic inflammation, blood lipids, lung function and airway inflammation were observed for either short-term or long-term PM2.5 exposure, or both. Collectively, we summarized representative exposure-response relationships between short- and long-term PM2.5 exposure and a wide range of cardiorespiratory outcomes applicable to China. The magnitudes of estimates were generally smaller in short-term associations and comparable in long-term associations compared with those in developed countries. Our findings are helpful for future standard revisions and policy formulation. There are still some notable gaps that merit further investigation in China.  相似文献   
92.
93.
Trace element analysis for five elements namely, Ba, Sr, Mn, Cr and Cd was carried out on both ash weight and dry weight basis for mine water and coconut water from Mangampeta barite area. The concentration of trace elements is strikingly different in the coconut water when compared with that of mine water. The coconut plant has the ability to control the presence of certain inorganic elements in its water, whatever be the amount of those elements present in irrigation water. Further, biogeochemical studies of coconut water may be of considerable importance in balneology.  相似文献   
94.
This paper identifies the coalitions involved in the topic of shale oil and gas development in India and identifies the circumstances surrounding a change in policy in 2013 by the Ministry of Petroleum and Natural Gas to promote shale exploration. Using the Advocacy Coalition Framework as the theoretical lens, the data are collected primarily from newspaper articles from 2010 to 2015 to identify coalitions, including actors’ positions, priorities, and interactions. The findings show the presence of a dominant advocacy coalition in favor of shale oil and gas development with priorities about energy security and a regulatory framework. The findings indicate some internal coalition disagreement, but stronger internal coalition agreement. Policy change was preceded by a spike in disagreement internal to the dominant coalition. This paper shows how a change in a dominant coalition can precede a change in policy, offers a replicable method of identifying and measuring coalitions via newspaper content analysis, provides a rare application of the Advocacy Coalition Framework outside of North America and Western Europe, and provides evidence of support for shale oil and gas development in India.  相似文献   
95.
Objective: In some countries, per se laws for other drugs than alcohol are used to judge drunk and drugged drivers. These blood concentration limits are often derived from experimental studies on traffic relevant behavior of healthy volunteers. Knowledge about how results from experimental studies could be transferred to a real-life setting is missing. The aim of this study was to compare impairment seen in experimental studies to the impairment seen at equivalent concentrations in apprehended drunk and drugged drivers.

Methods: Results from previously performed meta-analyses of experimental studies regarding impairment from alcohol, tetrahydrocannabinol (THC), and benzodiazepines were compared to impairment in apprehended drunk and drugged drivers as judged by a clinical test of impairment. Both experimental studies and real-life cases were divided into 4 groups according to increasing blood drug concentration intervals. The percentage of impaired test results in experimental studies was compared to the percentage of impaired subjects among drivers within the same blood drug concentration window.

Results: For ethanol, the percentage of impaired drivers (n = 1,223) increased from 59% in the lowest drug concentration group to 95% in the highest drug concentration group, compared to 7 and 72% in the respective groups in experimental studies. For THC, the percentage of impaired drivers (n = 950) increased from 42 to 58%, the corresponding numbers being 11 and 42% for experimental studies. For benzodiazepines, the percentage of impaired drivers (n = 245) increased from 46 to 76%, the corresponding numbers being 16 and 60% for experimental studies. The increased odds ratio for impairment between 2 concentration groups was comparable for experimental studies and impaired drivers.

Conclusions: Fewer test results indicated impairment in experimental studies compared to impaired drivers in real life when influenced by similar blood concentrations of either ethanol, THC, or benzodiazepines. In addition, a comparable relationship between drug concentration and impairment was seen for both experimental studies and real-life cases.

We believe that the present study strengthens the background for using experimental studies to establish fixed concentration limits for drunk and drugged drivers, but experimental studies in an impaired driver population could further expand our knowledge.  相似文献   

96.
Hybrid economy research in remote Indigenous Australia is what Gibson-Graham [2008. Diverse economies: performative practices for “other worlds”. Progress in Human Geography, 32 (5), 613–632] describe as a performative ontological project. This research seeks to address the marginalisation of customary economic activities that contribute to the well-being of Indigenous Australians. It aims to make the customary sector more real, more credible and more viable as an object of policy and activism, challenging the dual dominance of the state and the market as the focus of development (cf. Gibson-Graham 2008 Gibson-Graham, J. K. 2008. Diverse economies: performative practices for “other worlds”. Progress in Human Geography, 32(5), 613632. doi: 10.1177/0309132508090821[Crossref], [Web of Science ®] [Google Scholar]). This paper outlines how hybrid economy research has sought to broaden views of the economic landscape in remote Indigenous Australia amid the withdrawal of key policy and programmatic support by the Australian Government. This research draws on Canadian national surveys of Indigenous peoples, harvest studies and programmatic support for customary harvest – hunting, fishing and gathering of bush foods – to identify ways in which the Australian Government might better see and support Indigenous community food economies.  相似文献   
97.
薄晓波 《四川环境》2014,(4):154-156
环境法教学中案例教学具有十分重要的作用,可以帮助学生提高理论学习的效率和实务操作的能力。案例教学不仅仅是由教师单纯的讲授案例,还可以让学生去进行案例讨论。在案例教学中,教师需要选择合理的方式,持有宽容的态度,并做好充分的准备工作。  相似文献   
98.
ABSTRACT

Land-use decisions can change abruptly in response to shocks, and warfare and armed conflicts are among the most drastic and globally frequent shocks. Yet, our understanding of where armed conflict affects land systems, how land-use patterns are impacted, and how far-reaching and persistent these changes are, is partial. We used a spatially detailed dataset on armed conflict and a literature review to explore these questions. A number of key insights emerged from our study: (1) warfare and armed conflict affect land systems mainly in more densely populated areas, regardless of the dominating land use; (2) warfare and armed conflict can impact land systems in major ways, but these effects are diverse and not unidirectional; (3) warfare and armed conflict primarily affects land systems locally, but can forge telecouplings; and (4) although the impact of warfare and armed conflict is often immediate, it can instigate long-lasting land-use legacies.  相似文献   
99.
Wet air oxidation (WAO) is employed in this work for treating high concentration chemical wastewater containing phenol and/or phenolic compounds. Experimental results indicate that over 90% removal of phenol or phenolic compounds can be efficiently achieved in the WAO process. Despite of the high treatment efficiency of the WAO process, the treated wastewater, however, still retains relatively high chemical oxygen demand (COD) concentration and does not meet the safe discharge standard. Hence further treatment of the WAO treated wastewater by an aerobic biological treatment using acclimatized activated sludge is necessary. It is found in the present studies that the combined process, if appropriately operated, is capable of drastically reducing the COD concentration of the high concentration chemical wastewater to meet the safe discharge requirement. The operating conditions of the combined process are investigated to determine their respective effects on the overall treatment efficiency. The experimental data also indicate that the oxidation reaction can be represented by a first order kinetics in terms of the component or COD concentration. For both single component and multicomponent wastewaters, the WAO process was found to have different activation energy for oxidation below and above 200°C, suggesting possibly different reaction mechanisms between these temperature ranges. The experimental results provided in the present work can provide significant and practical information for optimizing the combined treatment method.  相似文献   
100.
It is observed that 1?→?3-β-glucan, a major cell wall component of fungi, induces pulmonary inflammation. There is inconsistency in determining the correlation between the levels of glucan measured by current extraction methods and the respiratory inflammation observed in individuals or lab animals exposed to environmental dust samples. The glucan-specific limulus amebocyte lysate (G-LAL) method was used after extraction with dimethyl sulfoxide (DMSO) or sodium hydroxide (NaOH) to analyze the glucan content of office dust samples collected from a water-damaged building. C3HeB/FeJ mice, an endotoxin-sensitive strain, were treated with different dust samples (2.5?mg?kg?1 body weight) or saline (vehicle control) by pharyngeal aspiration. At 1?day after aspiration, bronchoalveolar lavage (BAL) was performed, and lung inflammation and injury were assessed by measuring: (1) neutrophil (PMN) infiltration, (2) inflammatory cytokine (IL-6, IL-10, MCP-1, IFN-γ, TNF-α, and IL12-p70) levels, and (3) albumin and lactate dehydrogenase in recovered BAL fluid. Both DMSO and NaOH extraction increased the detection of glucan by approximately 20-fold compared to water extraction. However, only the DMSO extraction method showed a statistically significant positive correlation between 1?→?3-β-glucan and albumin levels, total numbers of BAL, polymorphonuclear leukocytes (PMNs) cells recovered, levels of TNF-α, MCP-1, and IL-6. In conclusion, 1?→?3-β-glucan is a potent inflammatory agent in dust samples and DMSO extraction for glucan analysis may prove useful in understanding the impact of environmental contamination by glucans on lung disease.  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