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   43篇
  免费   0篇
废物处理   2篇
环保管理   3篇
综合类   11篇
基础理论   8篇
污染及防治   13篇
评价与监测   4篇
社会与环境   2篇
  2023年   1篇
  2022年   1篇
  2021年   1篇
  2016年   6篇
  2015年   1篇
  2014年   3篇
  2013年   3篇
  2012年   2篇
  2011年   6篇
  2010年   6篇
  2008年   1篇
  2007年   1篇
  2006年   4篇
  2005年   2篇
  2004年   3篇
  2003年   1篇
  1993年   1篇
排序方式: 共有43条查询结果,搜索用时 0 毫秒
11.
This study investigated if atmospheric ammonia (NH3) pollution around a sheep farm influences the photosynthetic performance of the lichens Evernia prunastri and Pseudevernia furfuracea. Thalli of both species were transplanted for up to 30 days in a semi-arid region (Crete, Greece), at sites with concentrations of atmospheric ammonia of ca. 60 μg/m3 (at a sheep farm), ca. 15 μg/m3 (60 m from the sheep farm) and ca. 2 μg/m3 (a remote area 5 km away). Lichen photosynthesis was analysed by the chlorophyll a fluorescence emission to identify targets of ammonia pollution. The results indicated that the photosystem II of the two lichens exposed to NH3 is susceptible to this pollutant in the gas-phase. The parameter PIABS, a global index of photosynthetic performance that combines in a single expression the three functional steps of the photosynthetic activity (light absorption, excitation energy trapping, and conversion of excitation energy to electron transport) was much more sensitive to NH3 than the FV/FM ratio, one of the most commonly used stress indicators.  相似文献   
12.
13.
14.
Recent studies have shown that there are many effects of climate change on aeroallergens, and thus on allergic diseases in humans. In the Mediterranean region, despite the importance of the olive tree for production, there is high allergenicity of olive pollen and related risks to human health. Aerobiological sampling techniques can be used to analyse the pollinosis phenomenon through determination of mean daily pollen concentrations per cubic metre of air. The present study was carried out from 1999 to 2008 in 16 olive-growing areas in Italy, to update the information on the pollinosis characteristics of Olea europaea in the study areas. The analysis of the average flowering season over the study period highlights a temporal scaling of pollen in the atmosphere that depends on the different climatic characteristics. This is mainly dependent on temperature, and in part, determined by latitude. Generally, the levels of O. europaea pollen in the atmosphere are higher from mid-April to the end of June, with the period of greatest risk to human health due to this olive pollen in this area currently limited primarily to the last 10 days of May. However, the pollen season can move, depending on the climate scenario considered, and data here can be used to determine potential time shifts in pollinosis that might cause more precocious asthma and allergy problems. The allergy season for this type of pollen might be significantly precocious in future decades (20–30 days earlier in the year), which will impact on the severity and duration of allergies attributable to olive tree pollen.  相似文献   
15.
Omphalopagus conjoined twins were diagnosed by ultrasonography in a pregnant woman at 21 weeks' gestation. In order to clarify the anatomical connections, magnetic resonance imaging (MRI) was performed, having achieved fetal paralysis by intravascular injection of 100 mg of pancuronium into each twin. Prior to MRI, 2 ml of a 0.0001 mmol/ml solution of gadolinium DTPA was also injected into the stomach of one twin. The contrast agent opacified the bowel loops of both twins, indicating bowel to bowel anastomosis. Following pregnancy termination, autopsy confirmed the prenatal diagnosis.  相似文献   
16.
Environmental Science and Pollution Research - The Gulf of Naples located in a high anthropized coastal area is subjected to an infrastructural intervention for the installation of a submarine...  相似文献   
17.
We present and compare results obtained from the analysis of polychlorinated biphenyls (PCBs) of a limited number of contaminated soil samples collected in three areas of Basilicata region (south of Italy). The levels of PCBs were evaluated by using two analytical methods: (i) parallel dual-column gas-chromatography with dual electron capture detectors (GC-ECD) and (ii) gas-chromatography coupled to high-resolution mass spectrometry (GC-HRMS) via electron impact ionization (EI) in the multiple ion monitoring mode (MIM, two ions per compound). Two extraction methods prior to sample cleanup were also examined: microwave-assisted extraction (MAE) and ultrasonic-assisted extraction (UAE). The MAE was the extraction procedure adopted using acetone/n-hexane (1:1, v/v) as it is mainly characterized by higher sample throughput and allowed reduced consumption of organic solvents. While extraction and analysis of spiked soil samples showed the applicability of both methods, systematic differences between the results were obtained for the sum of PCBs as a result of some non-detected congeners by GC-ECD compared with GC-HRMS. Indeed, high resolution MS using EI mode (electron energy 40eV) with a resolving power of 10,000 provides additional information about the contamination pattern. The GC-ECD screening of 11 soil samples led to just one sample non-compliant to as it was close to the guide value for soils fixed by the Italian legislation (i.e., 60ppb for private or urban soil). Using GC-HRMS, the amount of all PCBs found ranged from 5.4 to 127ppb with five soil samples non-compliant to the guide value. The number of identified congeners ranged from 1 to 9 and 9 to 18 using dual-column GC-ECD and GC-HRMS, respectively.  相似文献   
18.
Environmental Science and Pollution Research - Microplastic pollution is one of the greatest environmental concerns for contemporary times and the future. In the last years, the number of...  相似文献   
19.
20.
In order to verify whether pollution is increasing or decreasing, in 25 locations uniformly distributed in the central part of the Lagoon of Venice, a transitional environment suffering from man's urban and industrial activities, the same sampling scheme was repeated three times (in 1987, 1993 and 1998) over a 12-year period during which the lagoonal environment underwent substantial changes. Superficial sediments were sampled and analysed for heavy metals and total organic carbon contents, grain size and density. In general heavy metal contents were found to be correlated, with concentrations above the background level, e.g., for Hg, a concentration factor of 24 was observed in 1987. A temporal decrease in concentrations was observed for most of the metals. Detailed analysis on a smaller spatial scale showed that contamination significantly decreases from the inner border of the lagoon seawards, as highlighted in contour maps. The role of the Porto Marghera industrial zone as a source of pollutants at the border of the Lagoon was confirmed. The decrease in contamination could not be attributed only to a decrease in the intensity of sources, but also to erosion processes, worsened by intensive harvesting of clams with hydraulic dredges.  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