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71.
Dragana??or?evi?Email author Drubavka?Radmanovi? Aleksandra?Mihajlidi-Zeli? Mila?Ili? Petar?Pfendt Zorka?Vukmirovi? Pedrag?Poli? 《Environmental Chemistry Letters》2004,2(3):147-150
We applied statistical methods to the data of a 5-year sampling period to characterize the features of trace elements in airborne particulate matter at the South Adriatic Coast. The analysis of surface soil samples was also performed. The data were processed by cluster analysis, enrichment factor determination and receptor rose statistics. It is shown that the principal element association consists of Fe, Mn and Ti originating from surface material resuspension. Hg and Se were shown to originate from more complex natural and anthropogenic processes. A strong emission source of Cd and Se was identified in the SSE direction.Selected article from the Regional Symposium on Chemistry and Environment Krusevac, Serbia, June 2003, organized by Dr. Branimir Jovancicevic. 相似文献
72.
随着营养学和现代生物技术的发展,发现日粮中微量元素在一定程度上影响动物基因的表达,这种作用可以发生在转录水平,也可以发生在转录后水平,进而影响机体的整个代谢过程.综述微量元素对基因表达调控的主要机制、存在方式,并介绍铁、硒、锌、铜、铅等元素对部分基因表达的主要影响. 相似文献
73.
Enrichment of potentially toxic elements in areas underlain by black shales and slates in Korea 总被引:6,自引:0,他引:6
Jin-Soo Lee Hyo-Taek Chon Jong-Shin Kim Kyoung-Woong Kim Hi-Soo Moon 《Environmental geochemistry and health》1998,20(3):135-147
The Okchon black shale in Korea provides an important example of natural geological materials containing toxic elements; the Chung-Joo, Duk-Pyung, Geum-Kwan, I-Won and Chu-Bu areas are underlain by these black shales and slates of the Guryongsan Formation. This formation is part of the Okchon Group which is found in the central part of Korea. Geochemical surveys were undertaken in these five study areas in the Okchon Zone in order to examine the level of enrichment and dispersion patterns of potentially toxic elements in rocks and soils. After appropriate preparation, samples were analysed by instrumental neutron activation analysis and inductively coupled plasma atomic emission spectrometry for a range of elements. Arsenic, Cu, Mo, V, U and Zn are highly enriched in the Okchon black shales and their mean concentrations are significantly higher than those in black slates. These elements are closely associated with one another from a geochemical viewpoint and may be enriched simultaneously. Mean concentrations of As, Mo and U in soils derived from black shales occurring in the Duk-Pyung and Chu-Bu areas are higher than the permissible level suggested by Kloke (1979), and the enrichment index decreases in the order of Duk- Pyung > Chu-Bu > Chung-Joo > Geum-Kwan = I-Won areas. Uranium-bearing minerals such as uraninite and brannerite have been identified in black shales from the Chung-Joo area by electron probe micro-analysis. Uraninite grains are closely associated with monazite and pyrite with a grain size ranging from 2m to 10m whereas brannerite grains occur as a euhedral form 50m in diameter. 相似文献
74.
Reconnaissance soil geochemical survey of Gibraltar 总被引:2,自引:0,他引:2
The extreme density of population of Gibraltar, situated at the southern tip of Spain, exerts considerable pressure on land use and thus future planning is of utmost importance. An initial reconnaissance soil geochemical survey of Gibraltar was based on 120 surface samples (0–15 cm) taken from a wide range of exposed, either bare soil or vegetated sites, to provide the optimum geographical distribution. The total elemental concentrations of 26 elements (Li, Na, K, Be, Mg, Ca, Sr, Ba, Al, La, Ti, V, Cr, Mo, Mn, Fe, Co, Ni, Cu, Ag, Zn, Cd, Pb, P, S, As) were determined by nitric/percholric acid digestion followed by inductively coupled plasma-atomic emission spectrometry (ICP-AES) analysis. The reconnaissance data shows that the spatial distribution of various elements depended on previous and present land use. Most elements (Ca, Cr, Mg and Mn excluded) exhibited relatively high concentrations in civilian and natural soils. Trends have been established for many elements, and concentrations exceeding guideline values have been found in certain areas of Gibraltar. This reconnaissance of Gibraltar is at present being followed by a more detailed baseline geochemical survey, which will establish the extent and magnitude of the variations in major and trace elements in soils and dusts, assess the impact of industrial, commercial and urban development on the geochemical landscape and to make recommendations concerning sustainable development. 相似文献
75.
模拟酸雨对土柱中稀土元素迁移的影响 总被引:4,自引:0,他引:4
模拟研究酸雨对土柱中稀土元素迁移的影响.结果表明,在雨水、酸雨淋溶下,对照组红壤土柱中所含稀土元素有向下迁移的趋势,并且随淋溶液pH值的降低,稀土元素向下迁移的能力增加.外源稀土迁移量的大小顺序为;Ce>La>Nd>Pr,其顺序与各稀土元素在稀土微肥中含量大小的顺序相同.表明外源稀土的迁移性与外源稀土的总量密切相关.外源稀土在土柱中的含量随着红壤深度的增加而减少,稀土元素主要在土柱中第一、二层持留;随着淋溶液酸度的下降,稀土元素向下迁移的能力增加. 相似文献
76.
Owing to its unique nutritional and immunological characteristics, human milk is the most important food source for infants. Breast milk can, however, also be a pathway of maternal excretion of toxic elements. Selected toxic elements (As, Pb, Mn,a Hg and Cd) were determined in human breast milk and blood samples obtained from 120 subjects related to an integrated steel plant environment located in central India. Samples of breast milk and blood from subjects living outside the steel plant environment were also analyzed for comparative study. Higher levels of these toxic elements were found in blood samples as compared to breast milk samples. Plant workers showed the higher presence of these metals in their breast milk and blood samples compared to the residents of the area and the subjects living outside the industrial environment, respectively. Mn, Pb and Hg have shown a higher tendency to associate with blood and breast milk than As and Cd. The order of occurrence of these metals in blood and milk samples thus found is Mn > Pb > Hg > As > Cd. 相似文献
77.
The distribution and enrichment of selected trace metals (Cd, Cr, Cu, Ni, Pb, Sn, Zn) in benthic sediments of the Southport
Broadwater, a semi-enclosed coastal body of water adjacent to the Gold Coast city, south-eastern Queensland, Australia, was
studied with the objective of assessing the extent and degree of sediment contamination. Sediment samples from the 0–10 cm
and 10–20 cm depth intervals of 32 sites within the Southport Broadwater and surrounding residential canals were analysed
for particle size distribution, pH, organic C and ‘near-total’ major (Al, Ca, Fe, Mn) and trace (Cd, Cr, Cu, Ni, Pb, Sn, Zn)
metal contents. Sediment contamination for each trace metal was assessed by (1) comparison with Australian sediment quality
guidelines, (2) calculation of the index of geoaccumulation based on regional background values, and (3) geochemical normalisation
against Al (i.e. the abundance of alumino-silicate clay minerals). Based on this approach, the results indicate that submerged
sediments in the study area are not presently enriched with Cd, Cr or Ni, with the spatial distribution of these metals being
very well explained by the abundance of alumino-silicate clay minerals. However, several sites were strongly enriched with
Cu, Pb, Sn and Zn, arising from sources related to either urban runoff or vessel maintenance activities. The study indicates
that several varying approaches are needed for a satisfactory assessment of contaminant enrichment in estuarine sediments. 相似文献
78.
初论元素富集成矿的地球化学机理—以岩浆热液矿床的形成为例 总被引:2,自引:0,他引:2
元素富集成矿的过程实质上是元素在地球不同圈层和不同相以及不同集合体之间分配的结果。元素的富集起始于地球形成的初期。对于大多数金属成矿元素 ,地壳特别是上地壳是大多数矿石和矿胎的储库 ,地壳丰度是元素富集成矿的物质基础。元素在地质体系演化共存相间的分配是元素富集成矿的关键过程。对于以侵入体为中心的热液矿床的形成 ,岩浆部分熔融、结晶分异、液态分离、挥发分分离以及气液相不混溶等过程能够导致金属元素最终达到矿石级的富集。挥发分则是元素富集成矿的重要制约因素 相似文献
79.
80.
本文提出将复合螯合剂(NaDDTC/8—Oxin)饱和吸附于活性碳上作为吸附材料.分离富集和ICP—AES同时测定水中痕量金属元素的方法。用ICP—AES研究了该吸附材料对某些痕量元素的吸附和解吸性能;考察了共存元素的影响。方法应用于湖水中Fe、Cu、Mn、Y和Sc的测定,检出限为ng/ml级,RSD为1.9%~4.4%,加入回收率81%~101%间,试样分析结果满意。 相似文献