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Effect of air drying on speciation of heavy metals in flooded rice paddies

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Chinese Chemical Letters 2012年第11期23卷 1287-1290页

作者： Bao Wang Biao Huang Yan Bing Qi Wen You Hu Wei Xia Sun Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beifing 100039China College of Natural Resource and Environment Northwest Agriculture and Forest UniversityYangling 712100China

Flooded soil samples were collected in the typical area of the Yangtze Delta Region; fractions of heavy metals in flooded and air dried samples were measured with BCR sequential extraction method and atomic absorption spectrometry. In flooded soils, fractions of heavy metals increased in the order of acid soluble 〈 oxidizable 〈 reducible 〈 residual. The acid soluble and reducible fractions significantly decreased but residual fraction significantly increased when the samples were air dried. The data obtained from air dried soil samples could not accurately represent the speciation of heavy metals in flooded field conditions.

关键词： Air drying Flooded Rice paddies Heavy metals speciation

Tb(Ⅲ) speciation in Human Blood Plasma by Computer Simulation

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Chinese Chemical Letters 2001年第9期12卷 809-812页

作者： Xing LU Key Lab. Rare Earth Chem. and Phys. Changchun Inst. of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

A multi-phase model was developed and Tb(III) speciation in human blood plasma was studied. At a concentration below 3.744x10-4mol/L (or at the concentration), Tb(III) is mostly bound to phosphate to form precipitate of TbPO4. As the concentration of Tb(III) increases, phosphate is exceeded and another kind of precipitate of Tb2(CO3)3 appears. Among soluble Tb(III) species, Tb(III) mainly distribute in [Tb (Tf)] at low concentration and in [Tb (HSA)], [Tb2 (Tf)], [Tb (IgG)], [Tb (Lactate)]2+, [Tb (CitArgH)] and free Tb(III) at high concentration.

关键词： Computer simulation Human blood plasma speciation Terbium (III)

Determination　of　speciation　of　Magnesium（Ⅱ）　in　Albumen　by　Gel　Permeation　Chromatography

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Chinese Chemical Letters 1996年第9期7卷 823-824页

作者： Ming SONG Hut Min MA Yue Xian HUANG and Shu Quan LIANG(Instituie of Chemistry, Chinese Academy of Sciences. Beijng 100080) Institute of Chemistry Chinese Academy of Sciences Beijing 100080

A gel permeation chromatographic method using cross-linked dextran G-50 was employed to determine the speciation of magnesium(Ⅱ) in albumen. It has been found that 0.22% of magnesium(Ⅱ) in albumen combines with prot... 详细信息

关键词： Determination speciation Albumen Gel Permeation

Distribution, Chemical speciation, and Environmental Risk Assessment of Heavy Metals in Tailings Soils near Dexing Copper Mine, China

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Journal of Donghua University(English Edition) 2012年第5期29卷 405-411页

作者：谢学辉范凤霞袁学武朱文祥刘娜平婧柳建设 College of Environmental Science and Engineering Donghua University

To complement information of heavy metals＇ distribution, chemical speciation, activity and environmental risks in agricultural soils surrounding tailings, a total of 16 samples obtained from the 4 # railings site of Dexing copper mine of China were investigated. The total concentrations of heavy metals Zn, Fe, Cu, Pb, Cd, Cr, Hg, As, Mn, Ag, Co, and Ni were determined by inductively coupled plasma-atomic emission spectrometry. Chemical speciations of Cu, Cd, and Zn were investigated with the procedures recommended by Tessier（1979）. Two different assessment approaches （GB 15618- 1995 and risk assessment code, RAC ） were employed to estimate heavy metals＇ environmental risks. Results indicated that heavy metals, especially Cu and Cd were in high levels of accumulation in these samples. Chemical speciation analysis results revealed that Cu was mainly in organic matter bound fraction （ORG） and residual fraction （ RES）, and Cd was predominantly in exchangeable fraction （EXC）, while Zn appeared mainly with the RES fraction. Environmental risk analysis results showed that Cd was in ＂heavy＂ pollution level （ classification m ） in almost all samples, which may exert ＂high＂ or ＂very high＂ environmental risks. Whereas, for Cu, one fourth samples showed ＂heavy＂ pollution level, but were located in ＂low＂ or ＂medium＂ environmental risk ranks. For Zn, many samples were grouped in ＂light＂ pollution level （ classification II ）, but were related to ＂ medium＂ and ＂ high＂ environmental risk ranks. These results indicated heavy pollution and high environmental risk of Cd in soils surrounding the 4# tailings site, which should be paid more attention to. Meanwhile, for Cu and Zn, the contrary results obtained by different environmental risk assessment approaches, may suggest that a more scientific, adequate environmental risk assessment criterion should consider both total content and chemical speciation activity of heavy metals.

关键词： mine tailing heavy metal speciation environmental risk assessment risk assessment code (RAC)

DNA barcoding, phylogenetic relationships and speciation of snappers (genus Lutjanus)

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Science China(Life Sciences) 2010年第8期53卷 1025-1030页

作者： WANG ZhongDuo1,2,3, GUO YuSong1,3, TAN Wei1, LI Lu1, TANG EnPu1, LIU ChuWu1,2,3 & LIU Yun2 1Fisheries College, Guangdong Ocean University, Zhanjiang 524025, China 2College of Life Science, Hunan Normal University, Changsha 410081, China 3Key Laboratory of Aquaculture in South China Sea for Aquatic Economic Animal of Guangdong Higher Education Institutes, Zhanjiang 524025, China Fisheries College Guangdong Ocean University Zhanjiang China College of Life Science Hunan Normal University Changsha China Key Laboratory of Aquaculture in South China Sea for Aquatic Economic Animal of Guangdong Higher Education Institutes Zhanjiang China

The phylogenetic relationships of 13 snapper species from the South China Sea have been established using the combined DNA sequences of three full-length mitochondrial genes (COI, COII and CYTB) and two partial nuclear genes (RAG1, RAG2). The 13 species (genus Lutjanus) were selected after DNA barcoding 72 individuals, representing 20 species. Our study suggests that although DNA barcoding aims to develop species identification systems, it may also be useful in the construction of phylogenies by aiding the selection of taxa. Combined mitochondrial and nuclear gene data has an advantage over an individual dataset because of its higher resolving power.

关键词： phylogenetic relationship Lutjanus speciation DNA barcoding

Accumulation and speciation of Arsenic in Pteris vittata Gametophytes and Sporophytes: Effects of Calcium and Phosphorus

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Pedosphere 2019年第4期29卷 540-544页

作者： YANG Guangmei WANG Yuanguo ZHU Lingjia HAN Yonghe Peter CHRISTIE Jiangsu Vocational College of Agriculture and Forestry State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing University Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of Sciences Tongren Polytechnic College

Dear Editor, Environmental arsenic (As) contamination of both soil and water systems is a worldwide problem, and As can enter the human food chain through contaminated agricultural products and drinking water and cont... 详细信息

关键词： Accumulation speciation Pteris vittata Gametophytes

Investigation of sulfur speciation in particles from small coal-burning boiler by XANES spectroscopy

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Chinese Physics C 2009年第11期33卷 1001-1005页

作者：包良满林俊刘卫陆文忠张桂林李燕马陈燕赵屹东何伟胡天斗 Shanghai Institute of Applied Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Institute of High Energy Physics Chinese Academy of Sciences

Sulfur K-edge X-ray absorption near-edge structure （XANES） spectroscopy was employed to study the speciation of sulfur in raw coal, ash by-product and fine particulate matter from a small coal-burning boiler. By means of least square analysis of the XANES spectra, the major organic and inorganic sulfur forms were quantitatively determined. The results show that about 70% of the sulfur in raw coal is present as organic and a minor fraction of the sulfur occurs as other forms： 17% of pyrite and 13% of sulfate. While in bottom ash, fly ash, and PM2.5, the dominant form of sulfur is sulfate, with the percentage of 80,79 and 94, respectively. Moreover, a number of other reduced sulfur including thiophenic sulfur, element sulfur and pyrrhotite are also present. During coal combustion, most of organic sulfur and pyrite were oxidized and released into the atmosphere as SO2 gas, part of them was converted to sulfate existing in coal combustion by-products, and a small part of pyrite was probably reduced to elemental sulfur and pyrrhotite. The results may provide information for assessing the pollution caused by small boiler and developing new methods for the control of SO2 pollution.

关键词： XANES sulfur coal PM2.5 speciation

Computer Simulation for Effect of Tb^(3+) on Ca^(2+)speciation in Human Plasma

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Journal of Rare Earths 2002年第3期20卷 238-240页

作者：卢兴王悦张海元王进平牛春吉倪嘉缵 Chinese Acad Sci Changchun Inst Appl Chem Key Lab Rare Earth Chem & Phys Changchun 130022 Peoples R China

Effect of Tb 3+ on Ca 2+ speciation in human plasma was studied by means of the computer program of MINTEQA2. When Tb 3+ ions are not added into the system, Ca 2+ ions mostly distribute in free Ca 2+ (74.7%) and the surplus distributes in Ca 2+ complexes, such as [CaHCO 3] +(7.9%), [Ca(Lac)] +(6.4%), CaHPO 4 (1 3%), [CaHistidinateThreoninateH 3] 3+ (2.4%), [CaCitrateHistidinateH 2] (2.3%) and CaCO 3(1.1%). Tb 3+ can compete with Ca 2+ for inorganic as well as biological ligands. An increase of concentration of Tb 3+ in the system results in an increase of content of free Ca 2+ and a decrease of contents of Ca 2+ complexes.

关键词： rare earths computer simulation speciation human plasma calcium terbium

Effect of Organic Materials on speciation of Copper inSoil Solution

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Pedosphere 1999年第2期9卷 139-146页

作者： WANG GUO CHEN JIANBIN GU XUNGANG GAO SHAN and CAI HAIYANG(Department of Land and Environmental Science, Fujian Agricultural University, Fuzhou 350002 (Chica)) 福建农业大学陆地与环境科学系福建福州 350002 福建农业大学陆地与环境科学系福建福州

Incubation of two soils, a red soil derived from granodiorte and a fluvo-aquic soil from alluvial deposit,with rice straw, Chinese milk vetch and pig manure under submerged condition were conducted to study thespecies of Cu in soil solutions as affected by the organic materials. The organic materials increased totalsoluble Cu by raising dissolved organic carbon (DOC) in soil solution when the solution pH values were belowthe range in which Cu deposited quickly. When the solution pH rose to this range, the increase of DOCdid not raise total soluble Cu. Total soluble Cu in all the treatments dropped with incubation time. Afteradding organic materials labile Cu dropped with incubation time and decreased sharply in the pH range ofCu precipitation. Addition of organic materials enhanced slowly labile Cu but depressed the ratio of labileCu to total soluble Cu. Slowly labile Cu decreased with incubation time. Stepwise multiple linear regressionanalysis showed that total soluble Cu was positively correlated with Eh and DOC (P=0.0025), labile Cuwas negatively correlated with pH (P=0.011 8), and slowly labile Cu was positively correlated with Eh andDOC (P=0.002 2). Both the labile and slowly labile Cu were correlated with total soluble Cu at extremelysignificant levels.

关键词： coppert dissolved organic carbon organic material speciation