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21.
Some fish‐kills in Basque rivers were studied by gill tissue analysis: Samples were wet digested and the solution was analyzed by atomic absorption spectroscopy. In three cases, the cause was linked to the effluents of an aluminium anodizing factory, cyanide caused one kill and copper wastes were related with another. Three cases were attributed to natural reasons and one of the kills was of unknown origin.  相似文献   
22.
Concentrations of nine inorganic elements (Na, Zn, Ca, Fe, Ni, Mn, Cu, Cd and Al) in particulate matter (PM10) in the air of an equatorial urban coastal location during 2009 were studied during summer and winter monsoon seasons using high-volume sampling techniques. Atomic absorption spectrophotometry was used to analyse the samples. The concentrations of most inorganic elements were higher during summer than winter, except for Cu and Zn. The main inorganic elements in PM10 are Na, Zn and Ca. High concentrations of Na and Ca are due to marine aerosols. Analysis of enrichment factors showed that inorganic elements are from non-crustal sources. Cluster analysis identified five clusters in the summer and six in the winter: (1) PM10–Ni, (2) Zn–Na, (3) Fe–Cu–Ca–Cd, (4) Mn and (5) Al for summer; and (1) PM10, (2) Zn, (3) Fe–Ni, (4) Cu–Ca–Na–Cd, (5) Mn and (6) Al for winter. Combining both correlation and cluster analysis, it was found that Fe–Cu–Cd was from industry/vehicle emissions, Zn was from resuspended soil, Mn was from metallurgical processes, Ni was from a nearby power plant and Al was from crustal sources. Inorganic element concentrations could be a good indicator of local sources of PM10.  相似文献   
23.
This study was aimed to evaluate the comparative distribution, correlation and apportionment of selected elements (Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Pb and Zn) in the scalp hair of arthritis patients and healthy subjects. The hair samples collected from the patients (rheumatoid and osteoarthritis) and healthy donors were digested in nitric acid and perchloric acid mixture, followed by the quantification of trace elements using atomic absorption spectrometry. In the case of healthy donors, highest mean concentration was shown by Ca (3240?µg?g?1), followed by Mg (340?µg?g?1), Zn (192?µg?g?1), Fe (184?µg?g?1) and Pb (27?µg?g?1), whereas, the estimated average metal levels in rheumatoid arthritis and osteoarthritis patients were 3160, 290, 197, 61 and 23?µg?g?1, and 3090, 300, 182, 50 and 21?µg?g?1, respectively. Most of the elements revealed diverse and random distribution in the scalp hair of the donor groups. The correlation study pointed out significant disparities in the mutual relationships among the trace elements in the patients and controls. Principal component analysis and cluster analysis of the element data manifested diverse apportionment of the selected elements in the scalp hair of the patients compared with the healthy counterparts.  相似文献   
24.
Lead (Pb) and cadmium (Cd) concentrations were determined in muscle, gonad, liver and brain of tilapia fish caught from fish ponds in Machakos and Kiambu counties in Kenya. A total of 217 fish samples were randomly sampled from the two counties. Acid digestion method and atomic absorption spectrophotometer were used for analysis. Heavy metal concentrations varied significantly depending on the type of tissue analyzed. Generally, the highest concentration of Pb was detected in brain and the liver. Fish organs contained Pb in the following order: brain > liver > muscle > gonad, while Cd followed the order: brain > liver > gonad > muscle. Kiambu county recorded higher concentration of the studied heavy metals compared to Machakos county although statistically there was no difference. Lead and Cd content in both counties studied exceeded the maximum allowable limit. The study recommended controlling industrial and agricultural effluents into surface water and proper sitting of ponds to minimize the risk of contamination of farmed fish by heavy metals.  相似文献   
25.
冷原子吸收法测定样品中汞含量时,需要对汞蒸气进行干燥,本文就实验中常用的几种干燥剂的性能以及不同的干燥剂对方法灵敏度的影响进行了实验和探讨。  相似文献   
26.
原子吸收光度法测定树叶中的重金属   总被引:5,自引:0,他引:5  
用浓硝酸与高氯酸消解树叶,Cu、Zn、Mn含量较高,可直接用火焰原子吸收法测定,含量较低的Pd、Cd,Cr则用石墨炉法测定。Pb及Cd含量甚微,受基体及共存元素干扰严重用标准加入法可消除干扰,结果令人满意。  相似文献   
27.
密封增压微波消化火焰原子吸收测定牡蛎中重金属含量   总被引:2,自引:0,他引:2  
本文采用降四氟乙烯密封增压微波消化法消解牡励样品,火焰原子吸收法测定其重金属Cu、Zn,Cd,Mn,Ni,Cr,Pb的含量,并与传统的混酸消化法和干灰化法的结果相比较,实验证明,本文方法的精密度、准确度、最低检出限都能很好地满足测定要求。该方法简便、快捷、节省能源和试剂,有较高的实用价值。  相似文献   
28.
分别用混合酸湿法消解和微波消解两种方法处理鱼虾样品,用原子吸收法测定样品中铜、锌、铅、镉、铬的含量.结果表明微波消解相对标准偏差均在4.0%以下,加标回收率在95.6%~112%之间.湿法消解相对标准偏差在0.3%~5.6%之间,加标回收率在88.9%~115%之间.微波消解比湿法消解的精密度、准确度高,且微波消解操作安全简便,耗时短,适用于样品数量多的情况.混合酸湿法消解操作复杂,耗时长,由于使用了在高温下易爆的高氯酸,又容易发生"炭化"现象,安全性差,在样品数量少的情况下可用此法.  相似文献   
29.
塞曼石墨炉原子吸收法测定废水中低含量锡   总被引:2,自引:0,他引:2  
试验了集恒温平台石墨炉 (STPF)于一体的纵向塞曼效应背景校正 ,最大功率升温 ,钯作为基体改进剂和峰面积积分 (A -s)测定废水中低含量锡的新方法。测定结果表明 ,锡含量在 0 μg/L~ 10 0 μg/L范围内呈良好的线性关系 ,检测限 (3σ) 3 5× 10 -11g ,特征量为 9 1× 10 -11g ,相对标准差小于 6 % ,回收率在 91%~ 10 7%之间  相似文献   
30.
Heavy metals in respirable suspended particulate matter (RSPM) were analyzed for different seasons, from July 2002 to December 2002, at different locations in Hisar (Haryana, India). The samples were analyzed for Pb, As, Ni, Cu, Mn, Fe and Mg on atomic absorption spectrophotometer (AAS) in air-acetylene flame. The concentration of heavy metals was more in the studied residential area followed by industrial area and commercial area. The concentrations of Fe, As, Ni and Mn were found to be more compared to other metals. Further, the concentrations of all the heavy metals were higher in pre-monsoon (extended summer) and monsoon followed by post-monsoon, autumn and winter. Meteorology played an important role in concentration of heavy metals in RSPM. Turbulent conditions resulted in higher concentration owing to re-suspension and external input whereas, low wind speed, low temperature and high relative humidity favoured low concentration of the pollutants. The evaluation of enrichment factor revealed that Pb, As, Ni, Cu, and Mn are emitted, chiefly from anthropogenic sources and Fe and Mg are associated with natural sources.  相似文献   
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