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121.
Occurrence of perfluorosulfonates and other perfluorochemicals in dust from selected homes in the city of Ottawa, Canada 总被引:1,自引:0,他引:1
A series of perfluorinated compounds (PFCs) including perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) have been recently measured in a variety of environmental samples and biological matrices. In order to better understand the human exposure routes of these chemicals, levels of PFOS, PFOA, perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHS) and perfluorooctane sulfonamide (PFOSA) in house dust samples were investigated. The data revealed a correlation between the concentrations of PFCs and the percentage of carpeting in the house; older houses tended to have less carpeting, hence lower levels of these perfluorinated compounds in their dust. 相似文献
122.
Eight heavy metals (Cu, Zn, Fe, Mn, Cd, Cr, Ni, and Pb) in 14 different wild-growing edible mushroom species (Coprinus comatus, Voluariella volvacea, Pleurotus nebrodensis, Hypsizigus marmoreus, Hericium erinaceus, Agrocybe aegerita, Lenfinus edodes, Collybia velutipes, Agaricus bisporus, Russula albida, Clitocybe conglobata, Pleurotus eryngii, Lepista sordida, and Pleurotus ostreatus) collected from Yunnan province, China, were determined by inductively coupled plasma-atomic emission spectrometry after microwave digestion. All element concentrations were determined on a dry weight basis. The ranges of element concentrations for copper, zinc, iron, manganese, cadmium, chromium, nickel, and lead were 6.8-31.9, 42.9-94.3, 67.5-843, 13.5-113, 0.06-0.58, 10.7-42.7, 0.76-5.1, and 0.67-12.9 mg/kg, respectively. In general, iron content was higher than other metals in all mushroom species. The levels of zinc, cadmium, and lead in some edible mushroom samples were found to be higher than legal limits. The relative standard deviations were found below 10%. The accuracy of procedure was confirmed by certified reference material. 相似文献
123.
124.
Zhang Y Chen Z Zhu B Luo X Guan Y Guo S Nie Y 《Environmental monitoring and assessment》2008,147(1-3):327-337
The objective of this study is to develop techniques for assessing and analysing land desertification in Yulin of Northwest China, as a typical monitoring region through the use of remotely sensed data and geographic information systems (GIS). The methodology included the use of Landsat TM data from 1987, 1996 and 2006, supplemented by aerial photos in 1960, topographic maps, field work and use of other existing data. From this, land cover, the Normalised Difference Vegetation Index (NDVI), farmland, woodland and grassland maps at 1:100,000 were prepared for land desertification monitoring in the area. In the study, all data was entered into a GIS using ILWIS software to perform land desertification monitoring. The results indicate that land desertification in the area has been developing rapidly during the past 40 years. Although land desertification has to some extent been controlled in the area by planting grasses and trees, the issue of land desertification is still serious. The study also demonstrates an example of why the integration of remote sensing with GIS is critical for the monitoring of environmental changes in arid and semi-arid regions, e.g. in land desertification monitoring in the Yulin pilot area. However, land desertification monitoring using remote sensing and GIS still needs to be continued and also refined for the purpose of long-term monitoring and the management of fragile ecosystems in the area. 相似文献
125.
126.
分析了《征收排污费暂行办法》在新形势下存在的问题,并从排污费的征收,管理和使用等方面提出了修改建议。 相似文献
127.
An attempt to evaluate the recharge source and extent using hydrogeochemistry and stable isotopes in North Henan Plain,China 总被引:2,自引:0,他引:2
Yan Zhang Fadong Li Guangshuai Zhao Jing Li Zhu Ouyang 《Environmental monitoring and assessment》2014,186(8):5185-5197
A thorough understanding of groundwater recharge source, particularly its rate, is usually a prerequisite for effective water resources management. In this paper, we report the impact of Yellow River water seepage from the North Henan Plain, using both hydrogeochemical and stable isotopic analysis data. Seven Yellow River water samples, 10 groundwater samples from a river-parallel transect, and 36 groundwater samples from four different perpendicular transects to the Yellow River in the western, middle, and eastern plain were collected and analyzed. It inferred that cation exchange of Ca2+ and/or Mg2+ for Na+ occurred in groundwaters because of the dissolution of carbonate rocks. The hydrogeochemical results indicate that western piedmont lateral groundwater and the Yellow River are both important sources of groundwater recharge for the western transect of the North Henan Plain, while the former is a greater recharge source for the middle transect, and the latter is a greater recharge source for the eastern transect. Stable isotope data support Yellow River water incursion into the groundwater. The approximate distance (based on chloride concentration) from the Yellow River to border of the impact zone is17.43–23.40 km in the western plain, 52.46 km in the middle plain, and 49.82 km in the eastern plain. 相似文献
128.
朱斌 《环境监测管理与技术》1995,7(5):15-16
连续5天腹腔注射同一剂量(1/5LD50)的合成洗涤剂,取小鼠骨髓细胞测定嗜多染色红细胞的微核率,研究表明,3种合成洗涤剂(加大香洗衣粉,洁牌餐具洗涤剂,恩威高级餐具洗洁精)使小鼠微核率有所增高,但恩威,洁牌餐具洗涤剂与对照无显著性差异。 相似文献
129.
Spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) in sediments of the Nansi Lake, China 总被引:2,自引:0,他引:2
Hong-Li Li Hong Gao Chen Zhu Guo-Gang Li Fan Yang Zheng-Yu Gong Jun Lian 《Environmental monitoring and assessment》2009,154(1-4):469-478
Polycyclic aromatic hydrocarbons (PAHs) were measured in surface sediments and dated core sediments from the Nansi Lake of China to investigate the spatial and temporal distribution characteristics. The concentrations of 16 kinds priority PAH compounds were determined by GC-MS method. And 210Pb isotope dating method was used to determine the chronological age of the sediment as well as the deposition rate. The results indicated that the total PAHs concentration ranges in surface and core sediment samples were 160 ~32,600 and 137 ~ 693 ng/g (dry wt.), respectively. The sediment rate and the average mass sedimentation were calculated to be 0.330 cm·year???1 and 0.237 g·cm???2·yr???1 and the sediment time of the collected core sample ranged from 1899 to 2000. The peak of PAH concentrations came at recent years. The source analysis showed PAHs mainly came from the contamination of low temperature pyrogenic processes, such as coal combustion. The PAHs concentrations were lower than ERL and LEL values for most collected samples. However, in several surface sediment samples especially in estuary sites, the PAHs concentrations were not only higher than ERL and LEL values, but also higher than ERM values. 相似文献
130.
本文通过对影响街道空气中一氧化碳污染的因素进行了大量的监测及综合分析,找出乌鲁木齐市主要街道空气中一氧化碳的污染规律,为控制我市汽车污染提供科学依据. 相似文献