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   137篇
  免费   1篇
  国内免费   2篇
安全科学   6篇
废物处理   5篇
环保管理   5篇
综合类   32篇
基础理论   21篇
污染及防治   51篇
评价与监测   8篇
社会与环境   12篇
  2023年   1篇
  2022年   5篇
  2021年   3篇
  2020年   1篇
  2019年   5篇
  2018年   11篇
  2017年   6篇
  2016年   7篇
  2015年   7篇
  2014年   13篇
  2013年   12篇
  2012年   8篇
  2011年   17篇
  2010年   1篇
  2009年   6篇
  2008年   10篇
  2007年   6篇
  2006年   4篇
  2005年   7篇
  2004年   4篇
  2002年   4篇
  2001年   1篇
  1995年   1篇
排序方式: 共有140条查询结果,搜索用时 640 毫秒
71.
Environmental Science and Pollution Research - Exposure to arsenic (As) increases cardiovascular risk. The purpose of this study was to evaluate the relationship between As and intima-media...  相似文献   
72.
Plastic debris were collected from eight beaches around San Diego County, California. Debris collected include: pre-production pellets and post-consumer plastics including fragments, polystyrene (PS) foam, and rubber. A total of n = 2453 pieces were collected ranging from <5 mm to 50 mm in size. The plastic pieces were separated by type, location, and appearance and analyzed for polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and its breakdown products, and chlordanes. PAH concentrations ranged from 30 ng g−1 to 1900 ng g−1, PCBs from non-detect to 47 ng g−1, chlordanes from 1.8 ng g−1 to 60 ng g−1, and DDTs from non-detect to 76 ng g−1. Consistently higher PAH concentrations found in PS foam samples (300-1900 ng g−1) led us to examine unexposed PS foam packaging materials and PS virgin pellets. Unexposed PS foam contained higher concentrations of PAHs (240-1700 ng g−1) than PS virgin pellets (12-15 ng g−1), suggesting that PAHs may be produced during manufacturing. Temporal trends of debris were investigated at one site, Ocean Beach, where storm events and beach maintenance were found to be important variables influencing debris present at a given time.  相似文献   
73.
The production of triplet states (T(*)) of chromophoric dissolved organic matter (CDOM), reacting with the probe molecule 2,4,6-trimethylphenol (TMP) was measured upon irradiation of water samples, taken from lakes located in a mountain area (NW Italy) between 1450 and 2750 m above sea level. The lakes are located below or above the tree line and surrounded by different vegetation types (trees, alpine meadows or exposed rocks). The most photoactive samples belonged to lakes below the tree line and their fluorescence spectra and CDOM optical features suggested the presence of a relatively elevated amount of humic (allochthonous) material. The lowest (negligible) photoactivity was found for a lake surrounded by exposed rocks. Its CDOM showed an important autochthonous contribution (due to in-lake productivity) and considerably higher spectral slope compared to the other samples, suggesting low CDOM molecular weight and/or aromaticity. Among the samples, CDOM photoactivity (measured as the rate of TMP-reactive T(*) photoproduction) decreased with changing vegetation type in the order: trees, meadows, rocks. It could be connected with decreasing contribution from catchment runoff and increasing contribution from autochthonous processes and possibly precipitation.  相似文献   
74.
Regional Environmental Change - To address sustainability challenges of agro-ecosystems located in Mediterranean urban regions, this paper focuses on the multidisciplinary subject of urban...  相似文献   
75.
- DOI: http://dx.doi.org/10.1065/espr2006.01.006 Background The use of vegetal organisms as indicators of contamination of the environment is partially replacing traditional monitoring techniques. Amongst the vegetal organisms available, mosses appear to be good bioindicators and are used for monitoring anthropogenic and natural fall-out on soils. This study has two objectives: the evaluation of the concentrations of heavy metals in soils and mosses of the Sicily Region, in Italy and the identification of the origin of fall-out of heavy metals. Methods Mosses and the surface soil were sampled at 28 sites, only the youngest segments of Hylocomium splendens and Hypnum cupressiforme, corresponding to the plant tissues produced during the last 3 years, were taken. The elements Cd, Cu, Ni, Pb and Zn were analysed by ICP-MS and Hg by AAS. Statistical analysis was by PCA and spatial representation by GIS. Results and Discussion In the mosses sampled in Sicily, the highest concentrations of Cd were found around the cities of Palermo and Messina. The highest concentrations of Hg were recorded in the northern part of the island between Trapani and Messina, similar to the distribution of Cu. Different areas with the highest concentrations of Ni were found near the south coast, in the vicinity of Palermo and around the Volcano Etna. The highest concentrations of Pb were found in the south-west coast near Agrigento, where important chemical plants and petroleum refineries are located. Except for a few locations, Zn fall-out was found to be evenly distributed throughout Sicily. Conclusion The sites where the concentrations of heavy metals cause greatest concern have been revealed by the PCA analysis and portrayed using GIS. Also of some concern is the diffuse and anthropogenic origin of Hg and Cd. The combined approach of using soil and mosses, together with pedological interpretation and application of multivariate statistical techniques has provided valuable insight into the environmental aspects of heavy metal deposition in a region of southern Europe. Recommendations and Outlook Further insight into the deposition of heavy metals will require more detailed sampling of soils and mosses in both new and previous study areas. This needs to be complemented by detailed pedological investigations in the study areas. Future research programmes will address these issues.  相似文献   
76.
Invasions of water bodies by floating vegetation, including water hyacinth (Eichhornia crassipes), are a huge global problem for fisheries, hydropower generation, and transportation. We analyzed floating plant coverage on 20 reservoirs across the world’s tropics and subtropics, using > 30 year time-series of LANDSAT remote-sensing imagery. Despite decades of costly weed control, floating invasion severity is increasing. Floating plant coverage correlates with expanding urban land cover in catchments, implicating urban nutrient sources as plausible drivers. Floating vegetation invasions have undeniable societal costs, but also provide benefits. Water hyacinths efficiently absorb nutrients from eutrophic waters, mitigating nutrient pollution problems. When washed up on shores, plants may become compost, increasing soil fertility. The biomass is increasingly used as a renewable biofuel. We propose a more nuanced perspective on these invasions moving away from futile eradication attempts towards an ecosystem management strategy that minimizes negative impacts while integrating potential social and environmental benefits.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01360-6) contains supplementary material, which is available to authorized users.  相似文献   
77.
Environmental Science and Pollution Research - Digital textile printing (DTP) is a game-changer technology that is rapidly expanding worldwide. On the other hand, process wastewater is rich in...  相似文献   
78.
Food and Environmental Virology - To observe the prevalence of contamination by hepatitis A virus (HAV) and norovirus (NoV) in different food types, 9242 samples were analyzed over a 6-year period...  相似文献   
79.
80.
OBJECTIVE: This study aimed to determine whether a persuasive educational intervention could increase licensure among motorcycle owners. Unlicensed motorcycle operators appear to be disproportionately involved in police-reported motorcycle crashes in Maryland, accounting for about 27% of motorcycle operators in police-reported crashes, although unlicensed owners comprise 17% of primary motorcycle owners. METHODS: A randomized controlled trial was conducted among unlicensed owners. Linking Maryland records of registered motorcycles with license files, 8,499 unlicensed owners who had no licensed co-owners were identified. Half were randomized to receive a persuasive educational mailing in early June 2005 from Maryland Motor Vehicle Administration (MVA). Motorcycle licenses can be attained by passing an accredited motorcycle training class or passing knowledge and skills tests administered by the state driver licensing agency. Licensure rates and motorcycle class enrollment were followed for 6 months post-intervention. RESULTS: As of December 16, 2005, 280 intervention group owners had obtained Class M motorcycle licenses and 158 had obtained Class R motorcycle learner's permits. The comparison group obtained 209 M licenses and 122 R permits. The overall success rate in the intervention group, defined as obtaining Class M or R, was 10.4% compared with 7.9% in the comparison group (licensure ratio (LR) = 1.33; 95% confidence interval (CI) = 1.16-1.52). The intervention was most successful among men, whose LR for obtaining M licenses was 1.45 (95% CI = 1.21-1.75). LRs were higher among owners ages 40-48 and 49+ receiving the intervention compared with younger groups. Motorcycle training class enrollment rates were higher in the intervention group, particularly among those taking a course for riders with intermediate skills (enrollment ratio = 2.24; 95% CI = 1.41-3.55). CONCLUSION: The intervention appeared to increase licensure, yet the licensure rate remained low among the intervention group. Potential risks and benefits of increasing the percentage of motorcyclists who are licensed need to be studied.  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