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Geoscience Frontiers 2019年第2期10卷 611-628页

作者： Mathias Schannor Cristiano Lana Marco A.Fonseca Applied Isotope Research Group Department of GeologyUniversidade Federal de Ouro Preto

Detrital zircon U-Pb geochronology combined with Hf isotopic and trace element data from metasedimentary rocks of the Aracuai Belt in southeastern Brazil provide evidence for break-up of the Congo-Sao Francisco Craton. The U-Pb age spectra of detrital zircons from metasediments of the Rio Doce Group(RDG) range from 900-650 Ma and define a maximum depositional age of ca. 650 Ma. Zircon trace element and whole rock data constrain an oceanic island arc as source for the deposition setting of the protoliths to the metasediments. Zircon ε_(Hf)(t) values from these rocks are positive between +1 and +15, supporting previous evidence of a Neoproterozoic extensional phase and oceanic crust formation in a precursor basin to the Aracuai Belt. Recrystallization of detrital zircon at ca. 630 Ma is compatible with a regional metamorphic event associated with terrane accretion to the Paleoproterozoic basement after transition from an extensional to a convergent regime. The juvenile nature, age spectra and trace element composition recorded in detrital zircons of metasediments from the Aracuai Belt correspond with zircons from metasedimentary rocks and oceanic crust remnants of other orogenic belts to its south. This suggests that rifting and oceanic crust formation of the entire orogenic system, the so-called Mantiqueira Province, was contemporaneous, most likely related to the opening of a large ocean. It further indicates that the cratonic blocks involved in the orogenic evolution of the Mantiqueira Province were spatially connected as early as 900 Ma.

关键词： Detrital zircon U-Pb geochronology Lu-Hf isotopes trace elements Aracuaí Belt

Relationship of trace elements Concentration and Growth Rate in Alsidium triquetrum (Rhodophyta)

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American Journal of Plant Sciences 2023年第3期14卷 323-338页

作者： Arsenio J. Areces Ruben Cabrera Jhoana Díaz-Larrea Ligia Collado-Vides Instituto de Geografía Tropical Ministerio de Ciencia Tecnología y Medio Ambiente Municipio Playa Ciudad Habana Cuba Gabinete de Arqueología Oficina del Historiador de la Ciudad Habana Vieja Cuba Unidad Iztapalapa Departamento de Hidrobiología Universidad Autónoma Metropolitana Ciudad de México México Department of Biological Sciences and Institute of Environment Florida International University Miami FL USA

Minerals and trace elements content and concentration in marine algae vary depending on species morphology and physiology;as well as growing environmental conditions. Despite this variability, accumulation of magnesium, and especially iron, seems to be common in Chlorophyta;while Rhodophyta and Heterokontophyta show higher affinity to manganese. The red agarophyte Alsidium triquetrum was used to analyze the relationship between metal concentration, environmental conditions and growth rate. Specimens grown in situ showed a large variability of Fe, Mn, Mg, and Al, in thallus tissue concentrations. Further, a compelling relationship between the growth rate and the thallus concentration of Mg and Mn, Zn, and Al was detecte. Manganese, unlike the other trace elements analyzed showed a positive linear relationship between growth rate and tissue content during the period of greatest vegetative growth.

关键词： Alsidium Growth Rate Manganese trace elements

Effect of Calcined Temperature on the Solubility of trace elements from Manifanshi

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Journal of Wuhan University of Technology(Materials Science) 2006年第2期21卷 146-149页

作者：洪汉烈 The Faculty of Earth Sciences China University of GeosciencesWuhan 430074 China

A medical stone manifanshi were researched by using polarized light microscopy, X-ray diffraction （ XRD ）, and inductively coupled plasma atomic emission spectrometry （ ICP-AES ） methods. The XRD pottern of the raw Manifanshi indicates that it is dominantly composed of plagioclase, orthoclase, quartz, and that of the calcined Manifanshi at 1000 ℃ shows that the distortion of crystal structure in both plagioclase and orthoclase takes place at the calcined temperature. The polarized light microscopy observation suggests that the Manifanshi is naturally weathered monzo-granite porphyry. Chemical analyses reveal that the Manifanshi contains a number of healthful trace elements and rare toxic trace elements, therefore, it is a htgh quality Manifanshi. The solubility of trace elements was determined by measuring the concentration of trace elements from Manifanshi calcined under varying temperature conditions by ICP method, the results suggest that the calcined prodact at 1000 ℃ shows the ideal result in ionic concentrations and dissolution rate of trace elements in water, which is contributed to the distortion of the crystal stracture of feldspar at the calcined temperature.

关键词： Manifanshi trace elements feldspar XRD ICP-AES

Research Progress on the Influence of trace elements on Osteoarthritis

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Chinese Journal of Biomedical Engineering(English Edition) 2022年第1期31卷 40-46页

作者： LU Fang LI Yu-yan ZHANG Min WANG Shuang-ge Jilin Kingmed for Clinical Laboratory Co. Ltd.Changchun Jilin 130000China

Osteoarthritis is a common clinical chronic degenerative disease with a gradually increasing morbidity as the population ages.The pathogenesis of the disease always maintained as a focus of clinicians’research.At present,the etiology and pathogenesis of osteoarthritis are far from clear.The attack of the disease has something to do with the patient’s joint inflammation,trauma and genetic factors,which is a result of joint action of multiple factors.trace elements are elements indispensable in the growth and development of the body.Despite it stiny content in the human body,it produces powerful biological effects and plays an important role in the growth and metabolism of the body.This paper studies the relevance between trace elements and osteoarthritis.

关键词： trace elements osteoarthritis superoxide dismutase

Determination of trace elements in High Purity Gold by High Resolution Inductively Coupled Plasma Mass Spectrometry

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Journal of Wuhan University of Technology(Materials Science) 2009年第4期24卷 608-612页

作者：谢华林 School of Chemistry and Chemical Engineering Central South University Department of Chemistry Hunan Institute of Technology

trace elements were determined in high purity gold by high resolution inductively coupled plasma mass spectrometry （HR-ICP-MS）. Sample were decomposed by aqua regia. To overcome some potentially problematic spectra/ interference, measurements were acquired in both medium and high resolution modes. The matrix effects due to the presence of excessive HCl and Au were evaluated. The optimum conditions for the determination was tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits range from 0.01ug/g to 0.28ug/g depending on the elements. The method is accurate, quick and convenient. It has been applied to the determination of trace elements in high purity gold with satisfactory results.

关键词： high purity gold trace elements high resolution inductively coupled plasma mass spectrometry spectral interferences

Geochemistry and Modes of Occurrence of Hazardous trace elements in the No.11 Coal Seam,Antaibao Surface Mine,Shanxi Province

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Acta Geologica Sinica(English Edition) 2007年第1期81卷 135-140页

作者： SONG Dangyu QIN Yong WANG Wenfeng ZHANG Junying ZHENG Chuguang Institute of Resources and Environment Henan Polytechnic University Jiaozuo Henan 454100 College of Mineral Resources and Geoscience China University of Mining and Technology Xuzhou Jiangsu 221008 State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan Hubei 430074

Concentrations of seventeen hazardous trace elements including As, Pb, Hg, Se, Cd, Cr, Co, Mo, Mn, Ni, U, V, Th, Be, Sb, Br and Zn in the No.ll coal seam, Antaibao surface mine, Shanxi Province were determined using Instrumental Neutron Activation Analysis （INAA）, Inductively Coupled Plasma Atomic Emission Spectrometry （ICP-AES）, Cold-Vapor Atomic Absorption Spectrometry （CV-AAS） and Graphite Furnace Atomic Absorption Spectrometry （GF-AAS）. Comparisons with average concentrations of trace elements in Chinese coal show that the concentrations of Hg and Cd in the No. 11 coal seam, Antaibao surface mine are much higher. They may be harmful to the environment in the process of utilization. The variations of the trace elements contents and pyritic suffur in vertical section indicated that：（a） the concentrations of As, Pb, Mn, and pyritic sulfur decrease from roof to floor; （b） the concentrations of Cr, Zn and Mo are higher in roof, floor and lower in coal seam; （c） the concentration of Br, Sb, and Hg are higher in coal seam and lower in roof and floor; （d） the concentrations of Mo, V, Th and AI vary consistently with the ash yield. Cluster analysis of trace elements, pyritic sulfur, ash yield and major elements, such as AI, Fe, P, Ca shows that：（a） pyritic sulfur, Fe, As, Mn, Ni, Be are closely associated and reflect the influence of pyrite; （b） Mo, Se, Pb, Cr, Th, Co, Ca and A! are related to clay mineral, which is the main source of ash; （c） U, Zn, V, Na, P maybe controlled by phosphate or halite; （d） Hg, Br, Sb and Cd may be mainly organic-associated elements which fall outside the three main groups. The concentration distribution characteristics of trace elements in coal seam and the cluster analysis of major and trace elements showed that the contents of trace elements in the No. 11 coal seam, Antaibao surface mine, are mainly controlled by detrital input and migration from roof and floor.

关键词： Antaibao surface mine trace elements geochemistry modes of occurrence Shanxi

Progress in the Application of Nano-trace elements in Animal Husbandry

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Animal Husbandry and Feed Science 2022年第1期14卷 45-49页

作者： Guo Shijin Zhang Zhimei Fu Shijun Tang Shiyun Li Ling Shandong Binzhou Animal Science&Veterinary Medicine Academy Binahou 256600China Shandong Lvdu Anie Veterinary Drug Industry Co. Ltd.Binzhou 256600China

Nano-trace element additives, with a particle size of 1-100 nm, are absorbed directly by osmosis in animals without ion exchange. When added to the feed, they can not only promote the growth by own nutrition at the conventional size, but also greatly improve the utilization and ab-sorption rate of additives by animals. In this paper, the researches on micro-element feed additives such as nano-selenium, nano-copper, nano-zinc and nano-chromium were reviewed, which will provide basis for breeding production.

关键词： Nano trace elements Animal husbandry Application

Experiment of Coal Leaching and Study of the Separation of trace elements

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 386-390页

作者： LIU Guijian Department of Earth and Space Science University of Science and Technology of ChinaNo.96 Jinzhai RoadHefei 230026Anhui

Leaching is an important way of separation of trace elements from coal. Based on leaching experiments, the content of trace elements separated out from coal is related to their existing state and content in coal, the duration of leaching process, temperature of leaching liquor and its acidity and basicity. The higher the temperature of leaching liquor and the longer the leaching time, the higher the contents of separated trace elements will be. In the course of leaching, the pH values of leaching liquors change and different trace elements are affected differently by the pH values.

关键词： Leaching experiment trace elements influence factors separation of trace element

Optimization of trace elements in purified glycerol for microbial lipid and citric acid production by Yarrowia lipolytica SKY7

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Systems Microbiology and Biomanufacturing 2021年第1期1卷 76-89页

作者： Lalit R.Kumar Sravan K.Yellapu R.D.Tyagi Patrick Drogui INRS-ETE 490Rue de la CouronneQuebecQC G1K 9A9Canada

Purified glycerol obtained after acid treatment of crude glycerol solution was used as the carbon source for lipid and citric acid production using Y.lipolytica SKY7.Although purified glycerol was high in phosphorus,it was important to inves-tigate the impact of fortification of trace elements in the medium on cell growth,lipid and citric acid(CA)production.When all the trace elements(including phosphates and sulfates)required for growth and lipid production were added to the purified glycerol medium,high biomass(51.67 g/L)and lipid concentration(19.47 g/L)were observed at 96 h of fed-batch fermentation with low CA concentration of 5.42 g/L.The purified glycerol medium without additional trace elements gave low biomass(27.67 g/L),lipid concentration(9.35 g/L)at 80 h of fed-batch fermentation,but gave high CA concentration(24.51 g/L).When purified glycerol was provided with only sulfates or all elements except KH_(2)PO_(4),low biomass(32.59 g/L and 38.52 g/L)and citric acid concentration(1 g/L and 2.42 g/L)were obtained at 96 h.

关键词： Yarrowia lipolytica SKY7 Purified glycerol trace elements Microbial lipid Citric acid

Geochemical characteristics of REY, Li, Ga trace elements in the No. 9 coal seam of the Daheng mine, Ningwu coalfield, Shanxi Province, China

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China Geology 2021年第2期4卷 266-273页

作者： Jin-xi Wang Zhi-heng Fu Ya-fan Hu Zhen Yang Jia-liang Ma Yu-zhuang Sun Key Laboratory of Resource Exploration Research of Hebei Province Hebei University of EngineeringHandan 056038China School of Resources and Geosciences China University of Mining and TechnologyXuzhou 221116China Institute for Atmospheric and Environmental Sciences Faculty of Geoscience and GeographyGoethe-University FrankfurtFrankfurt am Main 60438Germany

To understand the geochemical characteristics of the No.9 coal in the Daheng Mine of the Ningwu coalfield,the trace element analysis was conducted through X-ray fluorescence spectroscopy(XRF)and inductively coupled plasma mass spectrometry(ICP-MS).The sedimentary environment was discussed according to the element geochemical parameters.The results show that Li,Ga,Hf,Zr,Nb,Th,and Ta are slightly enriched in the No.9 coal of Daheng Mine.The average value of the rare earth elements and yttrium(ΣREY)in coal here is 144.20μg/g(excluding parting),which is higher than the average value ofΣREY in the world’s coal and China’s coal.The light rare earth elements(LREY)are enriched.The content of Eu was 0.12‒2.10μg/g with an average of 0.57μg/g,and the Eu is obviously negatively abnormal.Most of the trace elements in the coal are positively correlated with the ash content,which shows that the occurrence of these trace elements is related to inorganic minerals.The results of sequential chemical extraction experiments show that rare earth elements mainly exist in coal in the form of aluminosilicate.The value of the Sr/Ba and the content of S reflect that the coal-forming environment was influenced by seawater.The values of V/Cr and Ni/Co reflect that the peat swamp is in an anaerobic environment and a strongly reducing environment during the coal-forming period.

关键词： trace elements Rare earth elements Geochemistry Coal Taiyuan Formation Mineral exploration engineering Shanxi Province China