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   178篇
  免费   2篇
  国内免费   1篇
安全科学   14篇
废物处理   10篇
环保管理   9篇
综合类   47篇
基础理论   28篇
污染及防治   54篇
评价与监测   11篇
社会与环境   7篇
灾害及防治   1篇
  2023年   9篇
  2022年   5篇
  2021年   4篇
  2020年   3篇
  2019年   6篇
  2018年   8篇
  2017年   6篇
  2016年   9篇
  2015年   5篇
  2014年   8篇
  2013年   14篇
  2012年   10篇
  2011年   13篇
  2010年   4篇
  2009年   9篇
  2008年   10篇
  2007年   7篇
  2006年   11篇
  2005年   4篇
  2004年   5篇
  2003年   5篇
  2002年   7篇
  2001年   1篇
  2000年   1篇
  1999年   1篇
  1998年   1篇
  1996年   1篇
  1995年   1篇
  1994年   1篇
  1992年   1篇
  1986年   1篇
  1985年   2篇
  1984年   3篇
  1983年   2篇
  1981年   1篇
  1980年   1篇
  1964年   1篇
排序方式: 共有181条查询结果,搜索用时 0 毫秒
61.
Particulate matter air pollution is estimated to cause in the order of 350,000 excess deaths in the European Union calling for policy development and evaluation tools. In the current work, a model for PM10 exposures of children is developed using microenvironment time activities and infiltration of ambient pollution indoors, both evaluated against observations earlier and integrated with city-wide air quality models in the current work. The model is demonstrated using data from two cities in Italy. High-end short-term exposures are characterized by an episode-day situation in Turin, and annual mean exposures in downtown Bologna. The air quality model was unable to capture the highest levels during the episode, and therefore, the exposure model was adjusted using observed–modeled ratio from a monitoring station. Air quality model performance for the annual levels was significantly better. Annual exposure variability within the target population was 1.5-fold in the downtown area Bologna and tenfold during the episode day in Turin.  相似文献   
62.
The aim of the present study was to monitor mouthpart deformities of Chironomus plumosus (Insecta-Diptera) in Lake Trasimeno (2000-2010) in relation with sediment contamination by heavy metals, which is one of the main causes of deformity induction. In Lake Trasimeno, concentrations of heavy metals in the investigated littoral zone were low, in comparison with those of the central area. By contrast, the incidence of deformities was much higher in the littoral station (2006-2009) than in the central area. In the littoral zone, the deformities progressively decreased and by 2010 reached values similar to those observed in the central area (2000-2002, 2010). This decrease was mainly due to the reduction of severe deformities, thus indicating an environmental quality recovery of this littoral sector. Chemical analysis revealed that the higher incidence of deformities in the littoral zone was not caused by heavy metal contamination, unless they may have contributed to a joint action with other toxicants. The present study on Lake Trasimeno provided additional evidence that chironomid mouthpart deformities can be used in biomonitoring programs to evaluate sediment contamination by toxicants. Since mouthpart deformities may also be induced by compounds not included in routine chemical analyses, they may better reflect sediment quality than chemical analysis alone.  相似文献   
63.
A sharp increase in 2005 of pp'DDT and its metabolites was observed in mussels and fish from lakes Como and Iseo, the main glacier-fed southern Alpine lakes. DDTs in zebra mussels (Dreissena polymorpha) were more than 150 times higher than levels in 2003, and concentrations in pelagic fish (0.12 mgkg(-1) w.w.) exceeded the Italian safety threshold for human consumption (0.05 mgkg(-1) w.w.). The histological examination of the ovaries revealed many mussels with oocyte degeneration throughout the studied period. Prior to being banned in Italy in 1978, DDT was used in large amounts for fruit-tree treatment from the 1950s to 1970s in valleys just below the glaciers. Since glacier volume was increasing at that time and then continuously retreated, meltwater should be the main cause of the pollution peak recently observed in biota of downstream lakes. PCBs did not peak in biota tissues to a comparable extent probably because local sources were not as important as for DDTs.  相似文献   
64.
65.
66.
67.
68.
69.
Five cases of intestinal atresia were diagnosed using real-time ultrasonography following clinical evidence of polyhydramnios. No correlation was noted between ultrasound findings and the severity of the lesions. Two of the five babies died at 35 and 77 days respectively. Prematurity and presence of other abnormalities were factors in the deaths.  相似文献   
70.
Genetic differences in the Posidonia oceanica meadow of Monterosso al Mare (NW Mediterranean, Marine Protected Areas (MPAs) "Cinque Terre") were compared in three stations, at an increasing distance from a source of impact (beach nourishment) in the recent decade. Random amplified polymorphic DNA analysis showed a higher genetic variability (>20?%) in the area directly subjected to the stress, increasing with time. Clone integration, confirmed by phenotypic analysis, showed increases both in shoot density and leaf length connected to genetic differences observed in DNA fingerprints of new shoots. Analysis of molecular variance (AMOVA) showed 45?% individual differences within populations and 54?% among the populations. The fixation index (F (ST)?=?0.54), of the genetic differentiation, showed a marked difference between the populations at different temporal scales. Over a decade AMOVA indicated genetic variations from 28?% (1998) to 54?% (2009). These results make it clear that in the P. oceanica population examined the environment had, in ten years, selected those clones which were more resistant to the anthropogenic impact, despite being subjected to the effects of the resuspension of fine sediments. These findings could help to explain both the survival of the regressed Mediterranean P. oceanica meadows in areas subjected to moderate impacts and the extreme variability in success of revegetation experiments. Management of the ecological disturbance here described indicates also the timescale in population response to stress and its increased resilience in MPAs.  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