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concentrations of Heavy Metals in Suburban Horticultural Soils and Their Uptake by Artemisia selengensis

Pedosphere 2015年第6期25卷 878-887页

作者： CUI Xu SUN Xulei HU Pengjie YUAN Cheng LUO Yongming WU Longhua Peter CHRISTIE Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of Sciences University of Chinese Academy of Sciences College of Resources and Environment Shanxi Agricultural University Key Laboratory of Coastal Zone Environmental Processes Yantai Institute of Coastal Zone ResearchChinese Academy of Sciences

A total of 222 surface soil samples and 40 plant samples were collected to investigate the spatial distribution and possible sources of soil heavy metals and to know the uptake and translocation of heavy metals from roots to different plant parts in a representative vegetable production area in the Baguazhou Island, a suburb of Nanjing City, East China. The arithmetic mean values of total Cd, Cr,Cu, Ni, Pb, and Zn concentrations in the soils were 0.314, 133, 41.0, 58.0, 31.8, and 114 mg kg-1, respectively. All of these values were above the topsoil background values in the Nanjing area. Multivariate and geostatistical analyses showed that soil Cd contamination was derived mainly from agricultural practices. In contrast, Cu and Zn were derived mainly from soil parent materials and Pb from atmospheric deposition from highway gasoline stations. Artemisia selengensis, a locally important specialty vegetable, accumulated heavy metals primarily in the edible leaves. The general distribution of heavy metal concentrations in this plant species showed that the highest occurred in the leaves, intermediate in the stems and lowest in the roots. Cd had the highest concentration factor(root-to-soil ratio) and may pose increased health risks in the future to the local population through the consumption of contaminated vegetables.

关键词： concentration factor plant uptake pollution source spatial distribution translocation factor vegetable

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Determination of jumps for functions based on Malvar-Coifman-Meyer conjugate wavelets

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Science China Mathematics 2009年第3期52卷 443-456页

作者： SHI XianLiang HU Lan College of Mathematics and Computer Science Hunan Normal UniversityChangsha 410081China

In this paper we discuss determination of jumps for non-periodic function based on Malvar-Cofiman-Meyer (MCM) conjugate wavelets. We prove the equality of Lukacs type. Furthermore we establish several criteria on conc... 详细信息

关键词： MCM conjugate series concentration factor jump 42A50 42A16

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REE characteristics of the coal in the Erlian Basin, Inner Mongolia, China, and its economic value

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China Geology 2021年第2期4卷 256-265页

作者： Shao-qing Huang Shu-zheng Ning Jian-qiang Zhang Li Zhang Kang Liu Exploration and Research Institute China National Administration of Coal GeologyBeijing 100039China

The rare earth elements(REE)content of the coal in the Erlian Basin was determined by inductively coupled plasma mass spectrometry(ICP-MS),and it turns out that the REE content from different geological age shows a significant difference:The REE content of the coal in the Jurassic Alatanheli Group is from 152.05×10^(−6) to 1416.21×10^(−6),with an average value of 397.31×10^(−6),and the relative concentration factor shows enriched;the REE content of the coal in Early Cretaceous Baiyanhua Group is from 20.65×10^(−6) to 102.53×10^(−6),the mean value is 49.06×10^(−6),and the relative concentration factor shows *** REE distribution patterns samples in Jurassic and Cretaceous shows the difference:The REE pattern in Jurassic coal mainly manifests as H-type distribution,with the Y,Lu positive anomaly,it is speculated that the fluid carried REE ions into the coal-bearing basin,and the heavy REE gather in the coal due to the different chemical properties of each *** REE occurrence mode is presumed to be mainly *** type is the REE main distribution pattern in Cretaceous *** REE patterns in clastic rocks of the roof,parting and floor of coal seam are similar to the REE patterns in the coal and the most possible reason is that the REE main source is from the clastic *** showed that the coal of the Early Jurassic,especially of Amugulen coalfield has resource value.

关键词： Rare earth elements(REE) Distribution pattern type concentration factor Alatanheli Group Baiyanhua Group Economic value Erlian Basin Inner Mongolia China

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Study on accumulation of 137Cs in aquatic organisms

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Nuclear Science and Techniques 1998年第3期 56-57页

作者： Feng Ding Hua, Cheng Qi Jun ( Suzhou Medical College, Suzhou 215007, China) Cheung T ( City University of Hong Kong)

１Ｉｎｔｒｏｄｕｃｔｉｏｎ１３７Ｃｓｉｓｏｎｅｏｆｔｈｅｐｒｉｍａｒｙｆｉｓｉｏｎｐｒｏｄｕｃｔｓｄｉｓｃｈａｒｇｅｄｉｎｔｏｅｎｖｉｒｏｎｍｅｎｔａｔｎｕｃｌｅａｒａｃｃｉｄｅｎｔ．Ｂｅｃａｕｓｅｏｆｔｈｅｌｏｎｇ... 详细信息

１Ｉｎｔｒｏｄｕｃｔｉｏｎ１３７Ｃｓｉｓｏｎｅｏｆｔｈｅｐｒｉｍａｒｙｆｉｓｉｏｎｐｒｏｄｕｃｔｓｄｉｓｃｈａｒｇｅｄｉｎｔｏｅｎｖｉｒｏｎｍｅｎｔａｔｎｕｃｌｅａｒａｃｃｉｄｅｎｔ．Ｂｅｃａｕｓｅｏｆｔｈｅｌｏｎｇｈａｌｆｌｉｆｅｉｔｈａｓａｒｏ...

关键词： concentration factor Aquatic organisms Tissue distribution of 137 Cs

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Development of the ^(137)Cs,^(90)Sr and ^(3)H concentrations in the Hydrosphere in the Vicinity of NPP Temelín(South Bohemia)

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Journal of Environmental Protection 2015年第8期6卷 813-823页

作者： Eduard Hanslík Diana Maresova Eva Juranova Barbora Sedlarova Department of Radioecology T.G.Masaryk Water Research InstitutePragueCzech Republic Faculty of Science Institute for Environmental StudiesCharles UniversityPragueCzech Republic

The paperfocuses on an analysis of the results of long-term monitoring of the concentrations of 137Cs, 90Sr and 3H in hydrosphere in the vicinity of Temelín Nuclear Power Plant (Temelín plant). The radionuclides were monitored in surface water, river sediments, aquatic flora and fish species. The main objective of the study was to analyze and integrate all of the knowledge on concentrations and behaviour of these radionuclides, which originate mainly from residual contamination, in order to assess the impacts of Temelín Nuclear Power Plant on hydrosphere in these indicators during its standard operation and possible accidents. The radionuclides were analyzed in terms of spatial and temporal variability in their concentrations and their inflows and outflows, mainly into and from Orlík Reservoir. The analysis included standard radioecological characteristics, which were applicable for assessing long-term development and behavior of radionuclides in the environment affected by their possible accidental releases on the territory of the Czech Republic or outside this territory. For all of the components of the environment, the concentrations of 137Cs and 90Sr which were used for calculation of their effective and ecological half-time, were decreasing. For 137Cs in surface water and fish, the rates of the decrease in the first and second monitoring period were different. The rate of the decrease in 90Sr concentration was invariable. The results of the monitoring showed that 86% of suspended solids and 62% of 137Cs inflowing into Orlík Reservoir accumulated in the reservoir while accumulation of 90Sr was not substantiated. Outflows of 137Cs and 90Sr activities were assessed in relation to their concentrations that were accumulated in individual basins until 1986 consequently to Chernobyl accident and tests of atmospheric nuclear weapons. The results for the whole area of the Vltava, Luznice and Otava River basins upstream from the Vltava River at Solenice showed that durin

关键词： Caesium 137 Strontium 90 Tritium Effective Half-Time Ecological Half-Time Surface Water Sediments concentration factor Distribution Coefficient Radioecology

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与收入相关的老人健康不平等及其分解

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人口学 2012年第1期

作者：顾和军刘云平

本文使用“中国老年人健康长寿影响因素调查”(CLHLS)数据，测度了中国老人健康不平等程度，重点计算了收入、婚姻状况、居住安排等因素对健康不平等的贡献。回归基础上的集中系数及其分解结果显示：我国存在亲富人的健康不平等，高收... 详细信息

本文使用“中国老年人健康长寿影响因素调查”(CLHLS)数据，测度了中国老人健康不平等程度，重点计算了收入、婚姻状况、居住安排等因素对健康不平等的贡献。回归基础上的集中系数及其分解结果显示：我国存在亲富人的健康不平等，高收入人群的健康状况更好；城镇地区，健康不平等主要的贡献因素为收入、婚姻状况、医疗保险、经常锻炼，居住安排对健康不平等的贡献为负。农村地区，收入因素对于健康不平等的贡献最大，这就意味着消除农村健康不平等的关键是要降低收入不平等。在城镇和农村地区医疗保险的不平等程度更甚，进一步强化了健康不平等，因此如果政策想要降低健康不平等，首先要降低穷人获得医疗保险的经济门槛，增加医疗保健服务的可及性。

关键词：健康不平等健康指数集中系数健康不平等分解 health inequality health index concentration factor decomposition of health inequality

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