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Use of Flame Atomic Absorption Spectroscopy and Multivariate Analysis for the Determination of Trace Elements in Human Scalp 被引量:1
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作者 Sayo O. Fakayode Sri Lanka Owen +1 位作者 David A. Pollard Mamudu Yakubu 《American Journal of Analytical Chemistry》 2013年第7期348-359,共12页
The analysis of trace elements in human hair for use as biomarkers continues to generate considerable interest in environmental and bioanalytical studies, medical diagnostics, and forensic science. This study investig... The analysis of trace elements in human hair for use as biomarkers continues to generate considerable interest in environmental and bioanalytical studies, medical diagnostics, and forensic science. This study investigated the concentrations of essential and toxic elements (Fe, Mg, Ca, Cu, Zn, Cr, Cd, and Pb) using flame atomic absorption spectroscopy (FAAS) in human scalp hair obtained from subjects living in Forsyth County, North Carolina, USA. The influence of age, sex, race, and smoking habits on the levels of trace elements in the hair samples were also investigated. Additionally, analyses were subjected to a statistical, regression, and principal component analysis to evaluate inter-elemental association and possible pattern recognition in hair samples. Furthermore, Ca/Mg and Zn/Cu ratios, which are often used to evaluate the degree of Ca and Cu utilization in humans and as markers for various health related issues including, atherosclerosis, hypertension, insulin sensitivity, and pancreatic cancer, were calculated. The overall mean concentrations of Fe (25 μg/g), Ca (710 μg/g), Mg (120 μg/g), Zn (190 μg/g), Cu (12 μg/g), and Cr (0.20 μg/g) were found in hair samples. The trace element concentrations varied widely in hair samples as demonstrated by large range of concentrations obtained for each element. However, levels of Cd and Pb elements of <0.030 μg/g were detected in hair sample. In general, the levels of the trace elements in hair samples were poorly correlated. However, significant correlations were found between Ca and Mg (r = 0.840, p = 0.05). The levels of Fe, Ca, Mg, Zn, Cu, and Cr in hair samples and the calculated Ca/Mg and Zn/Cu ratios were found to be largely correlated with age, race, sex, and smoking habits. 展开更多
关键词 HUMAN SCALP HAIR BIOMONITORING trace element Concentration Flame Atomic Absorption SPECTROSCOPY Regression and Principal Component analysis Inter-element Association
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Preliminary study of the correlation between trace elements in human hair, liver and kidney by proton induced X-ray emission analysis
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作者 Zhang Yuanxun, Wang Xuepeng, Ying Jianhua, Qian Yine, Cheng Yuandi Shanghai hstitute of Nuclear Research, Acadenua Smica Shanghai China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1989年第1期91-97,共7页
This paper deals with the determination of trace elements in normal human hair, liver and kidney by Proton Induced X-ray Emission (PIXE) analysis. Sampling, specimen preparation and experimental procedures are describ... This paper deals with the determination of trace elements in normal human hair, liver and kidney by Proton Induced X-ray Emission (PIXE) analysis. Sampling, specimen preparation and experimental procedures are described in detail. The accuracy of our system has been checked up with the determination of standard reference materials. The preliminary results on correlations between trace elements in human tissues are discussed. Application of the method described in the paper gives evidence in favour of the PIXE as a good tool on environmental life elements and health studies. 展开更多
关键词 PIXE trace elements nuclear analysis human tissues.
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Method and portable facility for measurement of trace element concentration in prostate fluid samples using radionuclideinduced energy-dispersive X-ray fluorescent analysis 被引量:1
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作者 Vladimir Zaichick Sofia Zaichick German Davydov 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第6期93-100,共8页
A facility and method for109 Cd radionuclide-induced energy-dispersive X-ray fluorescent(EDXRF) were developed to determine the Fe,Zn,Br,Rb,and Sr concentrations in the specimens of human prostatic fluid.Specimens of ... A facility and method for109 Cd radionuclide-induced energy-dispersive X-ray fluorescent(EDXRF) were developed to determine the Fe,Zn,Br,Rb,and Sr concentrations in the specimens of human prostatic fluid.Specimens of expressed prostatic fluid were obtained from 51 men(mean age 51 years,range 18–82 years) with apparently normal prostates using standard rectal massage procedure.Mean values(M ± SEL) for concentration of trace elements(mg L^(-1)) in human prostate fluid were:Fe 9.04 ±1.21,Zn 573 ± 35,Br 3.58 ± 0.59,Rb 1.10 ± 0.08,and Sr B 0.76.It was shown that the results of trace element analysis in the micro-samples(20 l L) are sufficiently representative for assessment of the Fe,Zn,Br,and Rb concentration in the prostate fluid.The facility for109 Cd radionuclide-induced EDXRF is comparatively compact and can be located in close proximity to the site of carrying out the massage procedure.The means of Zn and Rb concentration obtained for prostate fluid agree well with median of reported means.For the first time,the Fe and Br concentrations,as well as the upper limit of the Sr concentration,were determined in the human prostate fluid. 展开更多
关键词 能量色散X射线荧光分析 放射性核素 元素浓度 便携式设备 前列腺 测定 样品 诱导
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Assessment of Minor and Trace Elements in Aquatic Macrophytes, Soils and Bottom Sediments Collected along Different Water Objects in the Black Sea Coastal Zone by Using Neutron Activation Analysis
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作者 Pavel Nekhoroshkov Alexandra Kravtsova +4 位作者 Alexander Kamnev Olga Bun’kova Octavian Duliu Marina Frontasyeva Igor Yermakov 《American Journal of Analytical Chemistry》 2017年第4期225-244,共20页
The levels and compartmentalization of Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Mo, Sb, I, Cs, Ba, La, Ce, Sm, Eu, Tb, Hf, Ta, Au, Th, and U in Phragmites australis (Cav.) Trin. ex... The levels and compartmentalization of Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Mo, Sb, I, Cs, Ba, La, Ce, Sm, Eu, Tb, Hf, Ta, Au, Th, and U in Phragmites australis (Cav.) Trin. ex Steud., Carex conescens L. and Cladophora sericea (Hudson) Kutzing from the Caucasian coast of the Black Sea-Anapa recreational region was investigated by Neutron Activation Analysis. The study touches upon subject of the sediment-to-plant and root-to-leaf elemental transfer as well as of the influence of anthropogenic pollution on wetland ecosystems in zone of resort. The content of the majority of considered elements was found higher in the belowground organs of P. australis than in the aboveground tissues while a reverse regularity was evidenced for C. conescens. The levels of elements decrease from bottom sediments to aquatic plants with the notable exception of the halogens Cl, Br and I that presented 5 to 100 fold higher content in plants than in sediments. The increased levels of As, Mo, and Sb in some soil and sediment samples most probably indicate the anthropogenic pollution. It recommends them for a continuous monitoring of the same area. 展开更多
关键词 trace elements Neutron Activation analysis The Black Sea PHRAGMITES AUSTRALIS (Cav.) Trin. ex Steud. CAREX conescens L. CLADOPHORA sericea (Hudson) Kutzing
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Micro-PIXE analysis of trace element composition and their distribution in minerals of mantle peridotite 被引量:1
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作者 陈友红 朱节清 +4 位作者 邬显慷 谷英梅 张旗 徐平 李秀云 《Nuclear Science and Techniques》 SCIE CAS CSCD 1996年第1期28-31,共4页
Micro-PIXEanalysisoftraceelementcompositionandtheirdistributionin mineralsofmantleperidotiteChenYou-Hong(陈友红... Micro-PIXEanalysisoftraceelementcompositionandtheirdistributionin mineralsofmantleperidotiteChenYou-Hong(陈友红),ZhuJie-Qing(朱节清... 展开更多
关键词 地质学 示踪元素组成 地幔橄榄岩矿石 分布
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Determination of Major, Minor and Trace Element Compositions of the Gd<sub>2</sub>O<sub>2</sub>S:Pr,Ce Scintillation Ceramics with Neutron Activation Analysis
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作者 Vladimir G. Zinovyev Ivan A. Mitropolskiy +6 位作者 Yuriy E. Loginov Georgiy I. Shulyak Tatyana M. Tyukavina Sergey L. Saharov Sergey V. Kosianenko Elena I. Gorokhova Vladimir A. Demidenko 《World Journal of Nuclear Science and Technology》 2014年第3期139-147,共9页
Neutron activation analysis technique of the Gd2O2S:М scintillation ceramics was developed. The concentrations of 15 trace, minor and major elements (As, Ce, Co, Cr, Cs, Eu, Fe, La, Sc, Tb, Zn, Zr, Pr, Gd, Na) have b... Neutron activation analysis technique of the Gd2O2S:М scintillation ceramics was developed. The concentrations of 15 trace, minor and major elements (As, Ce, Co, Cr, Cs, Eu, Fe, La, Sc, Tb, Zn, Zr, Pr, Gd, Na) have been measured with the instrumental neutron activation analysis of the Gd2O2S:Pr sample. The concentrations range of the determined elements is from 3 × 10-8 to 2.0% in mass. The determination limit of the elements was calculated to be (0.6 - 1.3 × 10-8% in mass). 展开更多
关键词 NEUTRON Activation analysis NUCLEAR Reaction trace elements Thermal NEUTRON Flux NUCLEAR Reactor
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Genesis of the Bianjiadayuan Pb-Zn polymetallic deposit, Inner Mongolia, China:Constraints from in-situ sulfur isotope and trace element geochemistry of pyrite 被引量:4
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作者 Kai-Rui Song Li Tang +7 位作者 Shou-Ting Zhang M. Santosh Christopher J. Spencer Yu Zhao Hao-Xing Li Liang Wang An-Li Zhang Yin-Qiang Sun 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第5期1863-1877,共15页
The Southern Great Xing’an Range (SGXR) which forms part of the eastern segment of the Central Asian Orogenic Belt (CAOB) is known as one of the most important Cu-Mo-Pb-Zn-Ag-Au metallogenic belts in China,hosting a ... The Southern Great Xing’an Range (SGXR) which forms part of the eastern segment of the Central Asian Orogenic Belt (CAOB) is known as one of the most important Cu-Mo-Pb-Zn-Ag-Au metallogenic belts in China,hosting a number of porphyry Mo (Cu),skarn Fe (Sn),epithermal Au-Ag,and hydrothermal veintype Ag-Pb-Zn ore deposits.Here we investigate the Bianjiadayuan hydrothermal vein-type Ag-Pb-Zn ore deposit in the southern part of the SGXR.Porphyry Sn ±Cu ± Mo mineralization is also developed to the west of the Ag-Pb-Zn veins in the ore field.We identify a five-stage mineralization process based on field and petrologic studies including (i) the early porphyry mineralization stage,(ii) main porphyry mineralization stage,(iii) transition mineralization stage,(iv) vein-type mineralization stage and (v) late mineralization stage.Pyrite is the predominant sulfide mineral in all stages except in the late mineralization stage,and we identify corresponding four types of pyrites: Py1 is medium-grained subhedral to euhedral occurring in the early barren quartz vein;Py2 is medium- to fine-grained euhedral pyrite mainly coexisting with molybdenite,chalcopyrite,minor sphalerite and galena;Py3 is fine-grained,subhedral to irregular pyrite and displays cataclastic textures with micro-fractures;Py4 occurs as euhedral microcrystals and forms irregularly shaped aggregate with sphalerite and galena.LA-ICP-MS trace element analyses of pyrite show that Cu,Pb,Zn,Ag,Sn,Cd and Sb are partitioned into pyrite as structurally bound metals or mineral micro/nano-inclusions,whereas Co,Ni,As and Se enter the lattice via isomorphism in all types of pyrite.The Cu,Zn,Ag,Cd concentrations gradually increase from Py1 to Py4,which we correlate with cooling and mixing of ore-forming fluid with meteoric water.Py2 contains the highest contents of Co,Ni,Se,Te and Bi,suggesting high temperature conditions for the porphyry mineralization stage.Ratios of Co/Ni (0.03-10.79,average 2.13) and sulphur isotope composition of sulfide indicate typical hydrothermal origin for pyrites.The δ^34SCDT values of Py1 (0.42‰-1.61‰,average 1.16‰),Py2 (-1.23‰ to 0.82‰,average 0.35‰),Py3 (-0.36‰ to 2.47‰,average 0.97‰),Py4 (2.51‰-3.72‰,average 3.06‰),and other sulfides are consistent with those of typical porphyry deposit (-5‰ to 5‰),indicating that the Pb-Zn polymetallic mineralization in the Bianjiadayuan deposit is genetically linked to the Yanshanian (JurassiceCretaceous) magmatic-hydrothermal events.Variations of d34S values are ascribed to the changes in physical and chemical conditions during the evolution and migration of the ore-forming fluid.We propose that the high Sn content of pyrite in the Bianjiadayuan hydrothermal vein-type PbeZn polymetallic deposit can be used as a possible pathfinder to prospect for Sn mineralization in the surrounding area or deeper level of the ore field in this region. 展开更多
关键词 trace elements in-situ sulfur ISOTOPE PYRITE Bianjiadayuan deposit SOUTHERN Great Xing'an range
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Seasonal variations and health risk assessment of trace elements in the Badigad River,lesser Himalayas,Nepal
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作者 Ramesh Raj Pant Kiran Bishwakarma +4 位作者 Kshitiz Kandel Sudip Poudel Jharana Nepal Bhanu Bhakta Neupane Virendra Bahadur Singh 《Acta Geochimica》 EI CAS CSCD 2023年第4期689-703,共15页
The consumption of contaminated river water can have severe effects on human health.This study aims to investigate the trace elements(TEs)content and their health risk assessment in the Badigad River Basin in the less... The consumption of contaminated river water can have severe effects on human health.This study aims to investigate the trace elements(TEs)content and their health risk assessment in the Badigad River Basin in the lesser Himalayas of Nepal.In total,44 water samples were collected from 22 different sites during the pre-monsoon and monsoon seasons,and 25 TEs were analyzed.Correlation matrix and principal component analysis(PCA)were used to analyze the potential relationship between the measured TEs and their source tracking.Furthermore,the water quality index(WQI),metal index(MI),and cancer index(CI)were evaluated.The TEs content in all samples were found to be within the WHO recommended guideline for drinking and domestic purposes.The dominancy order of the TEs was observed as Sr>Ba>Li>Rb>Zn>Cr>Sc>Mn>Ti>Cu>As>Ni>Co>U>V>Pb>Cs>Ga>Y>Tl>Th>Zr>Bi>Cd>Nb.The PCA analysis suggested that TEs could have natural,anthropogenic,and mixed origins.The WQI indicated that the river water is safe from a human health perspective.The MI suggested that Badigad River can be considered safer for drinking purposes,and the cancer index(CI)showed that all the reported TEs are at low-risk levels.The findings of this study could be useful for government agencies in developing more sustainable water management policies in the region.However,it is suggested that further investigations should be conducted in terms of other hydrogeochemical variables,including major ions,at spatiotemporal levels for the sustainability of the river basin. 展开更多
关键词 trace elements Water quality Health risk assessment Multivariate analysis Badigad River
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Arc-length technique for nonlinear finite element analysis 被引量:9
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作者 MEMONBashir-Ahmed 苏小卒 《Journal of Zhejiang University Science》 EI CSCD 2004年第5期618-628,共11页
Nonlinear solution of reinforced concrete structures, particularly complete load-deflection response, requires tracing of the equilibrium path and proper treatment of the limit and bifurcation points. In this regard, ... Nonlinear solution of reinforced concrete structures, particularly complete load-deflection response, requires tracing of the equilibrium path and proper treatment of the limit and bifurcation points. In this regard, ordinary solution techniques lead to instability near the limit points and also have problems in case of snap-through and snap-back. Thus they fail to predict the complete load-displacement response. The arc-length method serves the purpose well in principle, received wide acceptance in finite element analysis, and has been used extensively. However modifications to the basic idea are vital to meet the particular needs of the analysis. This paper reviews some of the recent developments of the method in the last two decades, with particular emphasis on nonlinear finite element analysis of reinforced concrete structures. 展开更多
关键词 非线性有限元分析 弧长技术 增强混凝土结构 平衡路径 分歧点
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A study of the relationship between trace element Mo and gastric cancer 被引量:4
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作者 CAO GuangHui1, YAN ShiMing2, YUAN ZhaoKang2, WU Lei2 and LIU YanFang2 《World Journal of Gastroenterology》 SCIE CAS CSCD 1998年第1期60-61,共2页
AstudyoftherelationshipbetweentraceelementMoandgastriccancerCAOGuangHui1,YANShiMing2,YUANZhaoKang2,WULei... AstudyoftherelationshipbetweentraceelementMoandgastriccancerCAOGuangHui1,YANShiMing2,YUANZhaoKang2,WULei2andLIUYanFang2S... 展开更多
关键词 tamach neoplasms/mortality molybdenum/analysis trace element risk factors
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Modelling of the relationship betwen trace elements and three species of sulfur in coal 被引量:1
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作者 Lu Xiao hua, Zeng Han cai National Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China Wei Lu xian Center of Microanalysis, Wuhan University of Automobile Industry, Wuhan, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第2期89-95,共7页
ModelingoftherelationshipbetwentraceelementsandthrespeciesofsulfurincoalLuXiaohua,ZengHancaiNationalKeyLa... ModelingoftherelationshipbetwentraceelementsandthrespeciesofsulfurincoalLuXiaohua,ZengHancaiNationalKeyLaboratoryofCoalCom... 展开更多
关键词 trace elementS COAL regression analysis factor analysis.
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Modes of Occurrence and Cleaning Potential of Trace Elements in Coals from the Northern Ordos Basin and Shanxi Province, China 被引量:9
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作者 WANGWenfeng QINYong JIANGBo FUXuehai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第4期960-969,共10页
Based on the analyses of 43 elements in 16 samples of the raw coal and feed coal collected from the northern Ordos basin and Shanxi Province, the modes of occurrence of these elements were studied using the method of ... Based on the analyses of 43 elements in 16 samples of the raw coal and feed coal collected from the northern Ordos basin and Shanxi Province, the modes of occurrence of these elements were studied using the method of cluster analysis and factor analysis, and the cleaning potential of the hazardous elements relatively enriched in the coals was discussed by analyzing six samples of the cleaned coal from the coal-washing plants and coal cleaning simulation experiments. The results shows that the elements Br and Ba show a strong affinity to the organic matter, Cs, Cd, Pb, Zn and Hg partly to the organic matter, and the other trace elements are mainly associated with the mineral matter. Cs, Mo, P, Pb,Zn and S have positive correlations with the two principal factors, reflecting the complexity of their modes of occurrence.Some elements that were thought to show a faint relationship (Be with S and Sb with carbonates) in other rocks are found to have a strong interrelation in the coals. Clay minerals (mainly kaolinite) dominate in the coals, and Ta, Th, Ti, Sc, REE,Hf, U, Se, W, V, Nb, Mo, Al, P, Cr, Pb and Zn are distributed mostly in kaolinite, while K, Rb, Cs, and Na have much to do with illite. Conventional cleaning can reduce the concentrations of most hazardous elements in various degrees. The hazardous elements S, As, Sb, Se, Mo, Pb, Cd and Hg relatively enriched in some coals from the area studied have a relatively high potential of environmental risks. However, by physical coal cleaning processes, more than 60% of As and Hg were removed, showing a high degree of removal, more than 30% of Sb, as well as S, Pb and Cd partly associated with the inorganic matter were removed. Se and Mo showing a relatively low degree of removal could be further removed by deep crushing of the coal during physical cleaning processes, and the concentrations of S, Pb, Cd and Hg with a partial association with the organic matter could be decreased in such ways as the coal blending. Cluster analysis together with factor analysis is a rapid and effective way to deduce the mode of occurrence of an element from bulk samples, and the removability data of most hazardous elements are basically consistent with their modes of occurrence suggested, which indicates that the statistical analysis could predict the cleaning potential of hazardous elements during the physical coal cleaning. 展开更多
关键词 微量元素 赋存集聚 鄂尔多斯盆地 陕西 煤矿
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Chemical characteristics of aerosols at coastal station in Hong Kong.Ⅱ. Environmental behavior of trace elements during the April 1995 to April 1996 被引量:3
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作者 K.S.Lam Z.L.Cheng +1 位作者 S.C.Kot C.W.Tsang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第2期212-221,共10页
An one-year of sampling aerosol program was carried out during the period of April 1995 to April 1996 at coastal region, Cape D′Aguilar, in Hong Kong. The trace element composition of aerosol particles(TSP and PM 10 ... An one-year of sampling aerosol program was carried out during the period of April 1995 to April 1996 at coastal region, Cape D′Aguilar, in Hong Kong. The trace element composition of aerosol particles(TSP and PM 10 ) were measured and analyzed by using the Instrumental Neutron Activation Analysis(INAA) and Inductive Couple Plasma-Mass Spectrometry(ICP-MS) techniques. The results showed that the polluted elements such as: V, Zn, As, Pb, Cd, Sb, I, Se, Bi, with high enrichment factor(E.F) values, are derived from anthropogenic sources, while Sc, Al, Fe, Mn, Sm, La, Sr are less than 10 in E.F, these elements are related the crust and soil. The concentration of the trace elements are present seasonal variation i.e. summer low and winter high, whereas the V or noncrustal V(V *) present summer high and winter low, this phenomenon might be explained by local or regional oil combustion sources. Use three type of elemental ratio, e.g. La/Sm, Mn */V * and Bi/Al indicate that both TSP and PM 10 of La/Sm ratios are mainly related to soil and dust, Mn */V * are probably represent fossil combustion and Bi/Al are possibly associated with refuse incineration, ferromanganese alloys and aluminum production. The varimax rotation factor analysis for trace elements was performed. By means of the absolute principal component analysis(APCA) and multiple regression, the contribution of trace elements to possible sources and overall means of trace elements were estimated. The results showed that the present station is impacted by the anthropogenic species, although the quantities are different during the summertime and wintertime. 展开更多
关键词 TSP PM10 微量元素 元素比例 季节性变动 因素分析
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Geochemical characteristics of trace elements in sediments of Dongting Lake, central China 被引量:2
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作者 Zhigang YAO Zhengyu BAO Pu GAO 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期137-137,共1页
关键词 污染因素 湖泊 地球化学 微量元素 沉积物
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Synchrotron radiation X-ray fluorescence analysis of Fe, Zn and Cu in mice brain associated with Parkinson's disease 被引量:2
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作者 田甜 张继超 +6 位作者 雷豪志 诸颖 施继晔 胡钧 黄庆 樊春海 孙艳红 《Nuclear Science and Techniques》 SCIE CAS CSCD 2015年第3期100-105,共6页
The contents and distributions of metal elements in the brain are closely related to neurodegenerative diseases.In this study, we examined Fe, Cu and Zn contents in the brain section associated with Parkinson‘s disea... The contents and distributions of metal elements in the brain are closely related to neurodegenerative diseases.In this study, we examined Fe, Cu and Zn contents in the brain section associated with Parkinson‘s disease(PD)using synchrotron radiation X-ray fluorescence(SRXRF). PD mouse model induced by 1-methyl-4-phenyl-1,2,3,6-terahydropyridine(MPTP) was used for the elemental analysis(e.g., Fe, Cu and Zn) in the substantia nigra pars compacta(SNpc) region of mice brain tissue samples. We found that mice in the MPTP group had higher contents of Fe, Cu and Zn in the SNpc than the control group. After treating the PD mice with rapamycin, the contents of Fe, Cu and Zn were reduced, the dopamine neurons and motor function were rescued correspondingly. The results prompted that the SRXRF provided an ideal method for tracing and analyzing the metal elements in the brain section to assess the pathological changes of PD model and the therapeutic effect of drugs. 展开更多
关键词 同步辐射X射线荧光分析 帕金森病 锌含量 鼠脑 低铁 神经退行性疾病 小鼠模型 Fe含量
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Measurement of trace element content in bone samples using long-lived neutron activation products and high-resolution gamma-ray spectrometry 被引量:1
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作者 Vladimir Zaichick Sofia Zaichick 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第1期21-28,共8页
A nondestructive instrumental neutron activation analysis with high-resolution gamma-ray spectrometry of long-lived radionuclides was developed and used for measurement of trace element contents in samples of bone to ... A nondestructive instrumental neutron activation analysis with high-resolution gamma-ray spectrometry of long-lived radionuclides was developed and used for measurement of trace element contents in samples of bone to determine health and diseases. Using this method, the silver(Ag), cobalt(Co), chromium(Cr), iron(Fe), mercury(Hg), rubidium(Rb), antimony(Sb), selenium(Se), and zinc(Zn) mass fractions were estimated in bone samples from 27 patients with intact bone(12 females and 15 males, aged from 16 to 49 years) who had died from various non-bone-related causes, mainly unexpected traumas,and from 5 patients with chondroma(2 females and 3males, 15–42 years old), obtained from open biopsies or after operation. The reliability of the differences in the results between intact bone and bone affected by chondroma was evaluated by a parametric Student's t test and a nonparametric Mann–Whitney U test. It was found that in the bone affected by chondroma, the mean mass fractions of Co, Cr, Fe, Se, Sb, and Zn were significantly higher than in normal bone tissues. In the neoplastic bone, many correlations between trace elements found in the control group were no longer evident. This work revealed that there is asignificant disturbance of the trace element metabolism in bone affected by chondroma. 展开更多
关键词 微量元素含量 高分辨率 中子活化 长寿命 Γ能谱法 活化产物 样品 测定
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REE and Other Trace Element Chemistry of Oldhamite(CaS)in the Qingzhen Chondrite(EH3)and Their Genetic Implications 被引量:1
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作者 陈永亨 王道德 ERNST PERNICKA 《Chinese Journal Of Geochemistry》 EI CAS 1993年第4期317-327,共11页
Instrumental neutron activation analysis(INAA) of 14 single oldhamite grains separated from the Qingzhen chondrite (EH3) for refractory(La,Ce,Sm ,Eu,Yb,Lu,Ca,Sc,Hf, and Th),volatile (Na,Cr,Zn,Se,Br,etc.)and siderophil... Instrumental neutron activation analysis(INAA) of 14 single oldhamite grains separated from the Qingzhen chondrite (EH3) for refractory(La,Ce,Sm ,Eu,Yb,Lu,Ca,Sc,Hf, and Th),volatile (Na,Cr,Zn,Se,Br,etc.)and siderophile elements (Fe,Ni,Co,Ir,Au ,and As) revealed that oldhamite is highly rich in refractory elements.The mineral serves as the principal carrier of REE and contains about 80% of the REEs in the Qingzhen enstatite chondrite .Furthermore, the large enrichment of LREE relative to HREE is noticed in oldhamite from the Qingzhen .In general, the oldhamite from metal-sulfide assemblages is richer in REE than that from the matrix,i.e.,the earlier the oldhamite grains condensed, the richer they are in REE. Meanwhile.oldhamite is also rich in vol-atile elements such as Se,Br, etc.In terms of the distribution of trace elements in oldhamitc from the Qingzhen ,the chondrite is srggested to have resulted from high-temperature condensation of solar nebula. 展开更多
关键词 球粒状陨石 硫化物 示踪元素 稀土元素 中子活化分析 顽辉石
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COMPOSITION ANALYSIS AND RESEARCH DEVELOPMENT OF NORTHERN FOREST ANTS
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作者 施亚琴 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1994年第4期49-51,共3页
The compositions of two kinds of ants (Formica cunicu Laria and Polyrhachis vicina Roger) were determined with modern apparatuses. The result was that content of crude protein, fat, vitamin E, formic acid were 43.95%,... The compositions of two kinds of ants (Formica cunicu Laria and Polyrhachis vicina Roger) were determined with modern apparatuses. The result was that content of crude protein, fat, vitamin E, formic acid were 43.95%, 22.90%, 15.61 mg / Kg, 4.2% respectively forFormica cunicu Laria, and 42.56%, 21 .90%, 131 .2 mg / Kg, 3.8% respectively for Polyrhachlk vicina Roger. 展开更多
关键词 ANT Composition analysis Protein VITAMIN Formic acid AMINOACID trace elements
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INVESTIGATION ON TRACE ELEMENTS IN CRUDE OILS AND ORGANIC MATERIALS EXTRACTED FROM OIL-FORMING SOURCE ROCKS IN CHINA WITH INAA
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作者 柴之芳 丁祖国 +1 位作者 傅家谟 盛国英 《Nuclear Science and Techniques》 SCIE CAS CSCD 1991年第2期85-90,共6页
A combination of Soxhlet extraction, column chromatography and INAA with GC and GC- MS was used in this work for the study of the abundance patterns of 36 trace elements and their correlation in nearly 100 samples of ... A combination of Soxhlet extraction, column chromatography and INAA with GC and GC- MS was used in this work for the study of the abundance patterns of 36 trace elements and their correlation in nearly 100 samples of crude oil and organic materials extracted from oil- forming source rocks from 10 main Chinese oilfields. The low V/Ni ratios of 0.01 to 0.3 state the oil- forming continent environment. The geochemical significance hinted from other trace element abundances is also briefly discussed. 展开更多
关键词 NEUTRON activation analysis CRUDE oil trace element pattern
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MATHEMATICAL STATISTICS OF HEAVY MINERALS AND THEIR REE AND TRACE ELEMENTS IN THE NORTHWESTERN SEA AREA OF ANTARCTIC PENINSULA
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作者 Wang Xianlan and Zhao YunlongSecond Institute of Oceanography, SOA, Hangzhou 310012 Beijing Institute of Uranium Geology, Beijing 100013 《Chinese Journal of Polar Science》 1990年第1期27-35,共9页
Based on the analysis and mathematical statistics of quantitative data on both the heavy minerals and their REE (La, Ce, Nd, Sm, Eu, Tb, Yb, Lu), trace (Zr, Hf, Th, Ta, U, Rb, Sr, Zn, Co, Ni, Cr, As, Sc) and major... Based on the analysis and mathematical statistics of quantitative data on both the heavy minerals and their REE (La, Ce, Nd, Sm, Eu, Tb, Yb, Lu), trace (Zr, Hf, Th, Ta, U, Rb, Sr, Zn, Co, Ni, Cr, As, Sc) and major (Fe) elements in the surface sediments in the northwestern sea area of Antarctic Peninsula, the authors find that the heavy minerals as the carriers of REE and trace elements should not be overlooked. Q-mode factor analysis of the heavy minerals provides a 3-factor model of the heavy mineral assemblages in the study area, which is mainly controlled by the origin of materials and sea currents. The common factor P<sub>1</sub>, composed mainly of pyroxene and metal minerals, and common factor P<sub>2</sub>, composed of hornblende, epidote and accessory minerals, represent two heavy mineral assemblages which are different from each other in both lithological characters and origin of materials. And common factor P<sub>3</sub> probably results from mixing of two end members of the above-mentioned assemblages.R-mode group 展开更多
关键词 Sea area of ANTARCTIC PENINSULA Marine SEDIMENTS Heavy MINERALS Rare earth and trace elements Statistic analysis.
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