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   277篇
  免费   4篇
  国内免费   1篇
安全科学   14篇
废物处理   12篇
环保管理   58篇
综合类   31篇
基础理论   59篇
污染及防治   57篇
评价与监测   15篇
社会与环境   26篇
灾害及防治   10篇
  2023年   3篇
  2022年   3篇
  2021年   3篇
  2020年   2篇
  2019年   5篇
  2018年   4篇
  2017年   4篇
  2016年   14篇
  2015年   4篇
  2014年   8篇
  2013年   24篇
  2012年   16篇
  2011年   8篇
  2010年   13篇
  2009年   18篇
  2008年   20篇
  2007年   11篇
  2006年   9篇
  2005年   12篇
  2004年   11篇
  2003年   9篇
  2002年   2篇
  2001年   11篇
  2000年   8篇
  1999年   2篇
  1998年   3篇
  1997年   4篇
  1996年   2篇
  1995年   3篇
  1994年   3篇
  1993年   2篇
  1992年   4篇
  1991年   8篇
  1990年   3篇
  1989年   3篇
  1987年   2篇
  1985年   2篇
  1984年   1篇
  1982年   5篇
  1980年   3篇
  1979年   3篇
  1978年   1篇
  1977年   1篇
  1975年   2篇
  1972年   2篇
  1970年   1篇
排序方式: 共有282条查询结果,搜索用时 31 毫秒
141.
The Japanese rural coastal areas are inherently vulnerable to typhoons and tsunamis. Their vulnerability has been further increasing recently, in part due to social factors such as the aging of society and depopulation. Following the Kobe earthquake of 1995, the Japanese government has promoted the Voluntary Disaster Preparedness Organization (VDPO) to build communities that are more sustainable and resilient to natural disasters. However, studies indicate that some VDPO activity has stagnated. The present study focuses on a rural coastal area in Japan and examines whether VDPO impacts residents’ awareness of disaster preparedness and also examines ties among the community. The study relies on a questionnaire survey. It reveals that VDPO contributes to improving both awareness of disaster preparedness and ties in the community.  相似文献   
142.
143.
Lyngbya majuscula is a benthic filamentous marine cyanobacterium, which in recent years appears to have been increasing in frequency and size of blooms in Moreton Bay, Queensland. It has a worldwide distribution throughout the tropics and subtropics in water to 30m. It has been found to contain a variety of chemicals that exert a range of biological effects, including skin, eye and respiratory irritation. The toxins lyngbyatoxin A and debromoaplysiatoxin appear to give the most widely witnessed biological effects in relation to humans, and experiments involving these two toxins show the formation of acute dermal lesions. Studies into the epidemiology of the dermatitic, respiratory and eye effects of the toxins of this organism are reviewed and show that Lyngbya induced dermatitis has occurred in a number of locations. The effects of aerosolised Lyngbya in relation to health outcomes were also reported. Differential effects of bathing behaviour after Lyngbya exposure were examined in relation to the severity of health outcomes. The potential for Lyngbya to exhibit differential toxicologies due to the presence of varying proportions of a range of toxins is also examined. This paper reviews the present state of knowledge on the effects of Lyngbya majuscula on human health, ecosystems and human populations during a toxic cyanobacterial bloom. The potential exists for toxins from Lyngbya majuscula affecting ecological health and in particular marine reptiles.  相似文献   
144.
145.
The need for cross-disciplinary scientific inquiries that facilitate improved natural resource management outcomes through increased understanding of both the biophysical and human dimensions of management issues has been widely recognized. Despite this broad recognition, a number of obstacles and barriers still sometimes challenge the successful implementation of cross-disciplinary approaches. Improving understanding of these challenges and barriers will help address them and thereby foster appropriate and effective utilization of cross-disciplinary approaches to solve natural resource management challenges. This research uses a case study analysis of the United States National Estuarine Research Reserve System to improve understanding of the critical factors that influence practitioners’ decisions related to incorporating social science into their natural resource management work. The case study research is analyzed and evaluated within a Theory of Planned Behavior framework to (1) determine and describe the factors that predict practitioners’ intent to incorporate social science into their natural resource related activities and (2) recommend potential strategies for encouraging and enabling cross-disciplinary approaches to natural resource management. The results indicate that National Estuarine Research Reserve practitioners’ decisions related to incorporating social science are primarily influenced by (1) confidence in their own capability to incorporate social science into their work and (2) beliefs about whether the outcomes of incorporating social science into their work would be valuable or beneficial.  相似文献   
146.
A field method is reported for the speciation of arsenic in water samples that is simple, rapid, safe to use beyond laboratory environments, and cost effective. The method utilises solid-phase extraction cartridges (SPE) in series for selective retention of arsenic species, followed by elution and measurement of eluted fractions by inductively coupled plasma mass spectrometry (ICP-MS) for “total” arsenic. The method is suitable for on-site separation and preservation of arsenic species from water. Mean percentage accuracies (n = 25) for synthetic solutions of arsenite (AsIII), arsenate (AsV), monomethylarsonic acid (MA), and dimethylarsinic acid (DMA) containing 10 μg l−1 As, were 98, 101, 94, and 105%, respectively. Data are presented to demonstrate the effect of pH and competing anions on the retention of the arsenic species. The cartridges were tested in the UK and Argentina at sites where arsenic was known to be present in surface and groundwaters, respectively, at elevated concentrations and under challenging matrix conditions. In Argentinean groundwater, 4–20% of speciated arsenic was present as MA and 20–73% as AsIII. In UK surface waters, speciated arsenic was measured as 7–49% MA and 12–42% DMA. Comparative data from the field method using SPE cartridges and the laboratory method using liquid chromatography coupled to ICP-MS for all water samples provided a correlation of greater than 0.999 for AsIII and DMA, 0.991 for MA, and 0.982 for AsV (P < 0.01).  相似文献   
147.
148.
149.
Lee RT  Shaw G  Wadey P  Wang X 《Chemosphere》2001,43(8):1063-1070
Soils initially contaminated with 36Cl in the chloride form were subjected to solid–liquid extractions using a variety of reagents including deionised water and 1 M sodium hydroxide (NaOH). 1 M NaOH was found to result in the greatest recovery of 36Cl from the soils, a result which provided initial evidence that radioactive chlorine became attached to humic substances present naturally within the soils. Deionised water and 1 M NaOH extracts were subjected to analysis involving separation by gel filtration chromatography (GFC). It was found that 36Cl in 1 M NaOH extracts associated preferentially with low molecular weight (LMW) fractions of humic substances whereas, in deionised water extracts, 36Cl appeared to be present exclusively in the chloride form. Previous literature evidence, mainly from highly organic forest soils, suggests that conversion of stable chlorine from chloride to organic forms can occur as a result of biological action. The present paper also presents good evidence for the specific attachment of stable chlorine (37Cl) to a LMW humic fraction, again demonstrated using GFC separation. Current risk assessments of the deep geological disposal of solid radioactive wastes containing 36Cl typically assume a very low degree of sorption based on the notion that the predominant environmental species of radiochlorine is chloride. This paper concludes with a brief discussion on the implications of organochlorine formation in the biosphere for assessment of the radiological impact of deep geological disposal of solid radioactive wastes.  相似文献   
150.
The degradability of several degradable polymers was examined using three types of degradation environments. These include exposure in a laboratory-scale composting test system containing material representative of the organic fraction of municipal solid waste (MSW), exposure in a thermal hydrolytic environment consisting of water at 60‡C, and exposure in a thermal-oxidative, dry oven environment of 60‡C. The results of the investigation clearly indicate that, in addition to chemical and biological activity which can lead to polymer degradation, physical restructuring and reorganization of the macromolecular structure may also occur at temperatures typically found in a compost environment, resulting in changes in the mechanical properties of the polymer films. In the case of the polyethylene-modified polymers evaluated in this study, all behaved similarly, but differently from the other polymer types. The polyethylene-based films appeared to be susceptible to oxidative degradation and should degrade in a composting environment providing that there is sufficient air in contact with the film for a sufficient period of time. However, when exposed in a laboratory composter, it appears that although ideal temperature-time curves may be obtained, the test time period was insufficient in comparison to the induction period required to achieve the desired thermal oxidative degradation. Issued as NRCC No. 37620.  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