The opening of the Central South Atlantic and the consequent formation of the eastern Brazilian continental margin was marked by a complex history of mafic magmatism,carbonate sedimentation,and deposition of a thick s...The opening of the Central South Atlantic and the consequent formation of the eastern Brazilian continental margin was marked by a complex history of mafic magmatism,carbonate sedimentation,and deposition of a thick salt layer.The carbonates underlying the salt layer(pre-salt carbonates)were formed in restricted lacustrine basins.Here,the timing and fluid sources of deposition,diagenetic,and hydrothermal alterations of the pre-salt carbonate rocks are defined through in-situ U-Pb dating,87Sr/86Sr,and trace element analyses of samples from the Santos Basin.The very alkaline nature of the Aptian lake(s)produced characteristically unique and widely distributed carbonate rocks such as Mg-clays with calcite spherulite and calcite crystal shrub limestones transitioning laterally and vertically into travertines formed by hydrothermal pulses during basin evolution.Hydrothermalism caused extensive replacement,dissolution,and calcite cementation.REE+Y PAAS-normalised patterns and 87Sr/86Sr ratios indicate that deposition/eo-diagenesis of the primary carbonates occurred in a lacustrine environment primarily controlled by evaporation,pH,and continental water source,with 2%–10%hydrothermal fluid input.Trace elements and Sr-isotope of travertines and burial diagenetic phases show that they are produced from a hot mixture of mafic/mantle-derived fluids and dissolution/alteration of older carbonate formations.U-Pb dating indicates that carbonate deposition occurred between 124.8±2.6 Ma and 120.0±1.6 Ma,earlier than previously proposed,followed closely by the circulation of hydrothermal fluids.Replacement and cementation ages range from 120.5±2.4 Ma to 80.4±2.4 Ma.展开更多
Quartz trace elements are extensively employed in studying magmatic evolution,fluid evolution,and metal enrichment.The Bianjiadayuan Ag-Pb-Zn-Sn deposit is a typical magmatichydrothermal system in northeastern China,h...Quartz trace elements are extensively employed in studying magmatic evolution,fluid evolution,and metal enrichment.The Bianjiadayuan Ag-Pb-Zn-Sn deposit is a typical magmatichydrothermal system in northeastern China,however,studies on its complex magmatic-hydrothermal evolution are limited.This study investigates the quartz from the Bianjiadayuan deposit to gain insight into the physicochemical evolution of mineralization using cathodoluminescence(CL)textures and laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS)of quartz.Five types quartz(Q1 to Q5)were identified.From Q1 in quartz porphyry to Q5 in Ag-Pb-Zn veins,the CL intensity and Ti content gradually decreases,and Ge,Ge/Ti,and Al/Ti ratios increase,indicating a temperature decline from magmatic to hydrothermal stages.The Sb content shows an opposite trend to Ti content,correlating positively with Ge content in quartz,suggesting that Sb content could also be temperature-dependent.These trace elements in quartz indicate cooling is critical for Ag mineralization.Furthermore,quartz phenocryst(Q1)from the quartz porphyry shows low Al/Ti(mostly<4)and Ge/Ti ratios(<0.04),suggesting a low degree of magmatic evolution.The Sb content in Q5 from Ag-Pb-Zn-quartz veins(>1 ppm,mostly tens of ppm)is notably higher compared to quartz in other lithologies including Sn-bearing quartz veins(<1 ppm),suggesting that Sb contents can serve as an effective indicator of Ag mineralization.展开更多
This work focused on determining the physico-chemical characteristics (pH, carbon and nitrogen) and trace metal elements (TMEs) content (As, Sb, Cd, Hg, Ni, Pb, Cr, Zn) of soils in the Brazzaville city. Soil samples w...This work focused on determining the physico-chemical characteristics (pH, carbon and nitrogen) and trace metal elements (TMEs) content (As, Sb, Cd, Hg, Ni, Pb, Cr, Zn) of soils in the Brazzaville city. Soil samples were taken from a depth of 0 to 20 cm using a hand auger on both banks of five tributaries of the Congo River (Djoué, Mfilou, Mfoa, Tsiémé, Djiri) that flow through the city of Brazzaville. 90 sampling points were defined, with 3 points 250 m apart on the banks and located, for each river, at three sites: upstream, midstream and downstream. Finally, 15 composite samples representative of the study area were taken. The average pH values of the water varied between 6.5 and 7.5. These pH values show that the soils studied are neutral. Total carbon content varied between 0.7% (Djiri) and 1.6% (Djoué). Total nitrogen content ranged from 0.08% (Djiri) to 0.12% (Djoué). TMEs contents varied from 0.5 to 1.8 mg/kg for Sb, from 0.5 to 2.5 mg/kg for As, from 0.1 to 0.18 mg/kg for Cd, from 4.2 to 11.3 mg/kg for Cr, from 0.07 to 0.27 mg/kg for Hg, from 0.7 to 2.4 mg/kg for Ni, from 0 to 158 mg/kg for Pb and from 16 to 105 mg/kg for Zn. The lowest TMEs levels were observed in the soils of the Djiri river, while the highest levels were observed in the soils of the Djoué and Tsiémé rivers. The ANOVA and Bonferroni test did not show significant differences in the means of the parameters measured (p > 0.05). The TMEs levels were below the accepted standards (NF U44-041), with the exception of Pb, which had high levels downstream of the Djoué. According to the pollution index values calculated using soil TME content, the soils on the banks of the Djoué river are considered polluted, while those on the banks of the Tsiémé river are moderately polluted, those on the banks of the Mfoa and Mfilou rivers are slightly polluted, and the soils on the banks of Djiri river are unpolluted.展开更多
The presence of inorganic constituents in coal is controlled by different geological factors,which,in turn,affect the technological,environmental,and health impacts of the coal.The main aim of this study is to objecti...The presence of inorganic constituents in coal is controlled by different geological factors,which,in turn,affect the technological,environmental,and health impacts of the coal.The main aim of this study is to objectively assess the mineralogical and geochemical characteristics of a thickest low-rank coal seam in the Lower Indus Basin southeastern Pakistan,and further investigate different controlling factors.The analytical results of major oxides,trace elements,and rare earth elements revealed that the weathering conditions were progressively variable and moderate.The sediment source,mainly of felsic and intermediate composition,was dominated by granitic rocks.The geochemical assessment reveals different depositional factors like marine environment influenced,while transitional and freshwater sediments influenced the center of the coal peat mire.Strontium,Zinc,and several hazardous trace elements,including Cu,Ni,Cr,and Co,have higher concentrations in these coals compared to world low-rank,U.S.,and Chinese coals.The relatively higher concentration of Sr in the thick coal seam in the Lower Indus Basin,compared to other coals seams in Pakistan and the enrichment of Sr was primarily controlled by the denudation of crystalline rocks and marine influx in the coal-basin.The REY distribution pattern showed that enrichment of medium and heavy rare earth elements is higher than light rare earth elements in the coal seam.The Gd distribution pattern in the coal seam demonstrated that strong positive anomalies had a good affinity with paleo-acidic water concentration in the study area.The higher concentration of Sr and other elements enables a better assessment understanding of the coal geochemical history.展开更多
The measurement of trace elements in Antarctic snow is crucial for understanding historical atmospheric geochemical changes and circulation patterns.However,studies on their spatial distributions remain limited,partic...The measurement of trace elements in Antarctic snow is crucial for understanding historical atmospheric geochemical changes and circulation patterns.However,studies on their spatial distributions remain limited,particularly those evaluating multiple metals across several snowpits,making interpretation challenging.This study investigates the distributions and sources of trace elements-including Cd,Ba,Pb,U,Bi,V,Mn,Fe,Cu,Zn,and As-across four snowpits in the Lambert Glacier Basin,East Antarctica.The trace elements exhibit site-,element-,and season-dependent variations,with higher concentrations observed at inland sites.In contrast,δ^(18)O and ion concentrations decrease with increasing distance from the coast and elevation,underscoring the influence of marine emissions.Crustal sources primarily contributed to Ba,U,V,Mn,and Fe,while non-crustal sources predominantly contributed to Cd,Bi,Zn,Pb,Cu,and As.Positive matrix factorization(PMF)analysis indicates that trace element concentrations in Pits 2 and 3 are influenced by both crustal and non-crustal sources,while Pit 4 reflects a mixed-source influence.Pit 1(coastal site)also indicates the mixed sources with influence of a highly dynamic marine climate and environment.The PMF results reveal similarities in emission sources and atmospheric transport patterns across the snowpits,facilitating a more comprehensive interpretation of longer ice core records.Overall,this study provides valuable insights into trace element distributions and enhances our understanding of past environmental and climatic conditions.展开更多
This review systematically summarizes the core advances in the field of trace elements and tumors,and clarifies the dual roles of key elements such as Zn,Cu,Fe,Se,Mn,and Ni in tumorigenesis(e.g.,DNA damage repair),tum...This review systematically summarizes the core advances in the field of trace elements and tumors,and clarifies the dual roles of key elements such as Zn,Cu,Fe,Se,Mn,and Ni in tumorigenesis(e.g.,DNA damage repair),tumor progression(e.g.,tumor microenvironment regulation),and therapeutic response-these elements not only possess tumor-suppressive potential but can also contribute to tumorigenesis.Meanwhile,it confirms the breakthrough value of multi-omics technologies and organoid models in deciphering the“element-cell-tumor”interaction mechanisms,which overcomes the limitations of traditional in vitro experiments and also points out the core directions for subsequent clinical research.展开更多
To study the distribution of 25 elements, i.e. Be, Cd, Ce, Cr, Cu, Dy, Er,Eu, Gd, Ge, Ho, La, Lu, Mo, Nd, Pb, Pr, Sm, Sr, Tb, Tl, Tm, Y, Yb and Zn in Phytolacca, atraditional Chinese medicinal herb, collected from nin...To study the distribution of 25 elements, i.e. Be, Cd, Ce, Cr, Cu, Dy, Er,Eu, Gd, Ge, Ho, La, Lu, Mo, Nd, Pb, Pr, Sm, Sr, Tb, Tl, Tm, Y, Yb and Zn in Phytolacca, atraditional Chinese medicinal herb, collected from nine areas of P. R. China. Methods Twenty-fiveelements in Phytolacca including essential elements, toxic elements and rare earth elements intraditional Chinese medicinal herbs from different areas were analyzed by ICP-MS. Results The 25elements in Phytolacca were determined by ICP-MS under optimized conditions. The detection limitswere 0.003 -0.71 ng·mL^(-1). The recoveries were 88% - 118% . The relative standard deviations ofthe measurements were 1.7% - 13.3%. Conclusion The determined concentrations of elements inPhytolacca acinosa Roxb vary from one area to another; however, the distribution tendency ofelements in all the samples is similar. The distribution tendency of rare earth elements inPhytolacca acinosa Roxb is consistent with that in nature.展开更多
The stimulative effect of trace elements on seed germination and seedling growth of Pinus tabulaeformis was tested. The experiments were carried out on seed soak and topdressing with different trace elements and varie...The stimulative effect of trace elements on seed germination and seedling growth of Pinus tabulaeformis was tested. The experiments were carried out on seed soak and topdressing with different trace elements and varied concentrations at the nursery of Gardens Research Institute, Harbin, in 2000-2001. The experimental results showed that soaking seed with 1% and 0.2% concentrations of Mn element produced best result for seed germination, and the germination rate was increased by 9%~19% for the seeds treated with 1% concentration and 12%~14% for the seeds treated with 0.2% concentration compared with the control group. The seeds treated with boron element had lowest germination rate. For trace element topdressing, Mn and Mo elements presented good result for seedling growth and the treatment with low concentration was even better. The height or chlorophyll content of the seedlings with spray of low-concentration Mn and Mo element was much higher than that of untreated ones. In the contrast to the treating method of seed soak, topdressing (application of spraying on foliage) had evident effect on seedling growth.展开更多
[Objective] This study aimed to promote the combination of cultivation and livestock farming, and to explore an environment-protecting farming style. [Method]The effects of anaerobically fermented complete compound so...[Objective] This study aimed to promote the combination of cultivation and livestock farming, and to explore an environment-protecting farming style. [Method]The effects of anaerobically fermented complete compound sow feed, added with Lactobacillus and Bacillus subtilis, on the chemical fractionation of copper, iron, zinc and manganese in feed and pig manure and skatole content in pig manure were investigated. [Result] Compared with those in the non-fermented feed, in the fermented feed and pig manure, the acetic acid-extractable copper, iron, zinc and manganese contents increased significantly（P0.05）, the reduced copper and iron contents increased significantly（P 0.05）, the oxidized copper and iron contents reduced significantly（P0.05）, and the residual copper contents remained unchangeable（P0.05）. The pH value of fermented feed decreased significantly（P0.05）, and that of pig manure increased significantly（P0.05）. The skatole content in pig manure decreased significantly（P 0.01）. The Lactobacillus abundance and amylase and cellulase activity increased significantly（P 0.05）. [Conclusion] The fermentation of feed changed the chemical fractionation of copper, iron, zinc and manganese in feed and pig manure, and reduced the manure odor.展开更多
In order to investigate the distribution of soil available micronutrients, and provide a theoretical basis for management of fertilizing reasonably on crops, the contents of major and trace elements （P, K, Ca, Mg, Cu...In order to investigate the distribution of soil available micronutrients, and provide a theoretical basis for management of fertilizing reasonably on crops, the contents of major and trace elements （P, K, Ca, Mg, Cu, Fe, Zn, and Mn） in farm- land soil collected from Yunnan Province were determined by inductively coupled plasma-mass spectrometry （ICP-MS）, the contents and distribution of major and trace elements were also studied. The results showed that the contents of available P, K were balance, available Ca, Mg were deficient, and available Cu, Fe, Zn, Mn were very plentiful. Major and trace elements distribution of different landform areas were obviously different. The contents of trace elements （Fe, Zn and Mn） of central Yunnan Red Plateau were significantly higher than those of Hengduan Mountains in western Yunnan and those of karst plateau in eastern Yunnan. The contents of available P, K, and Ca gradually declined from west to east, while the content of available Cu rose gradually from west to east. The results are reference value to elements determination and agricultural production in farmland soils.展开更多
AIMS The paper studies the relationship between spleen deficiency substance,spleen deficiency and gastric cancer. METHODS We adopted the IBAS 2000 image analysis system,501B SEM with 9100/60 energy chromatic dispersin...AIMS The paper studies the relationship between spleen deficiency substance,spleen deficiency and gastric cancer. METHODS We adopted the IBAS 2000 image analysis system,501B SEM with 9100/60 energy chromatic dispersing X-ray analysis instrument technique,histologic chemistry and radio-immunity means to assay the ultramicro structure,in- testinal rnetaplasia subtypes,cAMP,DNA,trace element series and their oxides of the patients' gastric mucosa. RESULTS The incidence rates of gastric cancer,incom- plete colonic intestinal metaplasia and“background lesion”of spleen deficiency with Qi stagnation patients are remarkably higher than those of spleen Qi deficiency patients(P<0.05- 0.001 ).The levels of gastric mucosa cAMP,Zn,Cu,ZnO and CuO decreased from complete to incomplete intestinal meta- plasia and from small to colonic intestinal metaplasia,while DNA increased in the above sequence(P<0.05-0.001 ).The lev- els of DNA,cAMP,Zn,Cu,ZnO and CuO in gastric mucosa of incomplete colonic intestinal metaplasia tissue are not remark- ably different from those in gastric cancer tissue. CONCLUSION Gastric diseases of spleen dificiency with Qi stagnation has the tendency of cancerization; There is a close relationship between the incidence of incomplete colonic intestinal metaplasia and gastric cancer.展开更多
The paper was to explore the effect of trace and secondary elements on scab of cucurbits （ Cladosporium cucumerinum） and their effects on enzyme activities of cucumber plants. [ Method ] Indoor antifungd experiment ...The paper was to explore the effect of trace and secondary elements on scab of cucurbits （ Cladosporium cucumerinum） and their effects on enzyme activities of cucumber plants. [ Method ] Indoor antifungd experiment and pot test was carried out to study the control effect of different trace and secondary dements on scab of cucu.rbits; after trace and secondary element compounds were sprayed for 7 d, the content of soluble protein and malondialdehyde （MDA） and the activities of peroxidase （POD） and superoxide dismutase （SOD） of cucumber leaves during seedling stage were simultaneously detected. [ Result] The inhibi- tion effects on scab of cucurbits were found in the three trace and secondary dements, especially for the CaC12 （66.9%）, and about 54.6% and 24.1% for ZnSO4 and H3 BO3 , respectively. When cucumber plants were infected by scab of cuea.rbits, the contents of MDA for all treatments were significantly decreased in cucum- ber leaves after spraying the three trace and secondary elements compared with control. The contents of soluble protein in cucumber seedling were increased by Zn- SO4 and H3 BO3 application, while the contents of POD and SOD were increased on ZnSO4 and CaCI2 treatments. The defense system of cucumber was induced and strengthened by application of the three trace and secondary elements. [ Conclusion ] The results provided the theoretical basis for practical application and research on resistance mechanism of using trace and secondary dements to control scab of eueurbits.展开更多
In the study, the contents of 5 trace elements including Fe, Cu, Mg, Mn and Ca were directly analyzed by flame atomic absorption spectroscopy in Gu- oshangye. The sample was subjected to microwave digestion with HNO3 ...In the study, the contents of 5 trace elements including Fe, Cu, Mg, Mn and Ca were directly analyzed by flame atomic absorption spectroscopy in Gu- oshangye. The sample was subjected to microwave digestion with HNO3 and H2O2, and detected by the standard curve method. The results showed that Guoshangye contained abundant trace elements which rates of these trace elements were in the curacy and satisfactory. were necessary for human. The recovery range of 96%-103%. The method is ac-展开更多
[Objective] This study aimed to investigate the trace elements in Rehman- nia glutinosa Libosch. by using principal component analysis and clustering analysis. [Method] Principal component analysis and clustering anal...[Objective] This study aimed to investigate the trace elements in Rehman- nia glutinosa Libosch. by using principal component analysis and clustering analysis. [Method] Principal component analysis and clustering analysis of R. glutinosa medicinal materials from different sources were conducted with contents of six trace elements as indices. [Result] The principal component analysis could comprehen- sively evaluate the quality of R. glutinosa samples with objective results which was consistent with the results of clustering analysis. [Conclusion] Principal component analysis and clustering analysis methods can be used for the quality evaluation of Chinese medicinal materials with multiple indices.展开更多
[Objective] This study aimed to analyze the contents of trace elements in potatoes from different production areas in Qinghai Province. [Method] By flame atomic absorption spectrometry （FAAS）, the contents of variou...[Objective] This study aimed to analyze the contents of trace elements in potatoes from different production areas in Qinghai Province. [Method] By flame atomic absorption spectrometry （FAAS）, the contents of various trace elements in potatoes were determined. [Result] Potatoes contain abundant trace elements such as Cu, Zn, Fe, Mn, Ca, K and Mg. To be specific, the contents of Ca, K and Mg were relatively high. [Conclusion] By using FAAS, the relative standard deviation was 1.17%-2.75% and the recovery rate was 97%-99.5%, indicating accurate and reli-able results with high precision.展开更多
[Objective] This study aimed to investigate the effect of trace elements in peanut seed coating agent. [Method] Different concentrations of trace elements Fe and B were added into peanut coating agent, then the germin...[Objective] This study aimed to investigate the effect of trace elements in peanut seed coating agent. [Method] Different concentrations of trace elements Fe and B were added into peanut coating agent, then the germination rate and plant height of the seeds treated by different agents were measured to decide the best formula. [Result] The germination rate and plant height of the seeds treated with seed coating agent was obviously increased. Adding trace elements Fe and B could increase the peanut yield, and 1.5% Fe and 1% B gave the best result. [Conclusion] This study will provide reference for modifying the seed coating agent formula.展开更多
Trace elements and rare earth elements（REE） of the sulfide minerals were determined by inductively-coupled plasma mass spectrometry.The results indicate that V,Cu,Sn,Ga,Cd,In,and Se are concentrated in sphalerite,Sb...Trace elements and rare earth elements（REE） of the sulfide minerals were determined by inductively-coupled plasma mass spectrometry.The results indicate that V,Cu,Sn,Ga,Cd,In,and Se are concentrated in sphalerite,Sb,As,Ge,and Tl are concentrated in galena,and almost all trace elements in pyrite are low.The Ga and Cd contents in the light-yellow sphalerites are higher than that in the brown and the black sphalerites.The contents of Ge,Tl,In,and Se in brown sphalerites are higher than that in light-yellow sphalerites and black sphalerites.It shows that REE concentrations are higher in pyrite than in sphalerite,and galena.In sphalerites,the REE concentration decreases from light-yellow sphalerites,brown sphalerites,to black sphalerites.The ratios of Ga/In are more than 10, and Co/Ni are less than 1 in the studied sphalerites and pyrites,respectively,indicating that the genesis of the Tianqiao Pb-Zn ore deposit might belong to sedimentary-reformed genesis associated with hydrothermal genesis.The relationship between LnGa and LnIn in sphalerite,and between LnBi and LnSb in galena,indicates that the Tianqiao Pb-Zn ore deposit might belong to sedimentary-reformed genesis.Based on the chondrite-normalized REE patterns,δEu is a negative anomaly（0.13-0.88）,andδCe does not show obvious anomaly（0.88-1.31）;all the samples have low total REE concentrations（〈3 ppm） and a wide range of light rare earth element/high rare earth element ratios（1.12-12.35）.These results indicate that the ore-forming fluids occur under a reducing environment.Comparison REE compositions and parameters of sphalerites,galenas,pyrites,ores,altered dolostone rocks,strata carbonates,and the pyrite from Lower Carboniferous Datang Formation showed that the ore-forming fluids might come from polycomponent systems,that is,different chronostratigraphic units could make an important contribution to the ore-forming fluids.Combined with the tectonic setting and previous isotopic geochemistry evidence,we conclude that the ore-deposit genesis is hydrothermal,sedimentary reformed,with multisources characteristics of ore-forming fluids.展开更多
China’s energy dependents on coal due to the abundance and low cost of coal.Coal provides a secure and stable energy source in China.Over-dependence on coal results in the emission of Hazardous Trace Elements(HTEs)in...China’s energy dependents on coal due to the abundance and low cost of coal.Coal provides a secure and stable energy source in China.Over-dependence on coal results in the emission of Hazardous Trace Elements(HTEs)including selenium(Se),mercury(Hg),lead(Pb),arsenic(As),etc.,from Coal-Fired Power Plants(CFPPs),which are the major toxic air pollutants causing widespread concern.For this reason,it is essential to provide a succinct analysis of the main HTEs emission control techniques while concurrently identifying the research prospects framework and specifying future research directions.The study herein reviews various techniques applied in China for the selected HTEs emission control,including the technical,institutional,policy,and regulatory aspects.The specific areas covered in this study include health effects,future coal production and consumption,the current situation of HTEs in Chinese coal,the chemistry of selected HTEs,control techniques,policies,and action plans safeguarding the emission control.The review emphasizes the fact that China must establish and promote efficient and clean ways to utilize coal in order to realize sustainable development.The principal conclusion is that cleaning coal technologies and fuel substitution should be great potential HTEs control technologies in China.Future research should focus on the simultaneous removal of HTEs,PM,SOx,and NOx in the complex flue gas.展开更多
The purpose of the present study was to survey contents of trace elements of Cu, Mn, Fe, and Zn in the surface layer （0-20 cm） in the soil, pasture and serum of sheep in Huangcheng area of Qilian mountain grassland,...The purpose of the present study was to survey contents of trace elements of Cu, Mn, Fe, and Zn in the surface layer （0-20 cm） in the soil, pasture and serum of sheep in Huangcheng area of Qilian mountain grassland, China. Also the soil-plantanimal continuum was analyzed. Soil （n=300）, pasture （n=60）, and blood serum samples from sheep （n=480） were collected from Huangcheng area of Qilian mountain grassland, China. The contents of trace element in the samples were analyzed by atomic absorption spectrophotometer after digestion. The soil trace elements density distribution shows a ladder-like pattern distribution. Equations developed in the present study for prediction of Fe （R2=0.943） and Zn （R2=0.882） had significant R2 values.展开更多
Optical microscopy and scanning electron microscopy in conjunction with energy dispersed X-ray spectrometry(SEM–EDX)were used to study the minerals and the concentrations of 33 trace elements in No.6 coal from Heidai...Optical microscopy and scanning electron microscopy in conjunction with energy dispersed X-ray spectrometry(SEM–EDX)were used to study the minerals and the concentrations of 33 trace elements in No.6 coal from Heidaigou mine.The distributions,organic affinity and removability of 18 trace elements were studied by float-sink experiments.A determination of the maceral groups was also undertaken.A high mineral content,dominated by kaolinite,was found in No.6 coal from Heidaigou mine.The bauxite content was relatively high and it was mainly present as individual particles in fusinite lumens or was intimately intergrown with carbonate minerals.The pyrite and quartz contents were low.Some marcasite with a parallel twin structure was observed by cross-polar reflected light.A small amount of bean-like goyazite was present in the calcite.The weighted trace element content in Heidaigou formations is relatively low,which is beneficial for coal processing and utilization.The concentrations of Ga,Hg,Pb,Se,Th,Ta are relatively high compared with the average values of Chinese coals.As,Hg,Mo,Ge,Ga,Ta,Ti,W,Mn are mainly present in minerals while B,Be,Th,P,Sc,Sr,V,Y,Yb are mainly found in organic matter.As,Ge,Hg,Mo are mainly present in sulfides and Be,Th,P,Sc,Sr,Y,Yb are mainly present in inertinite.B and V are mainly present in vitrinite.The high organic affinity and the low theoretical removability of most trace elements cause difficulties in removing them during coal preparation.展开更多
基金C.Lana and F.F.Alkmim benefit from the Brazilian National Research Council(CNPq)research grants 3073353/2019-2 and 311543/2020-0.C.Lana,F.F.Alkmim,and Maria Eugênia Souza are part of the Instituto GeoAtlântico,a National Institute of Science and Technology,CNPq-Brazil process 405653/2022-0We acknowledge Petrobras’s support during the investigation and permission to publish this study.I.Figueiredo acknowledged the Brazilian Federal Agency for Support and Evaluation of Graduate Education(CAPES)for Master's scholarship 88887.816343/2023-00.
文摘The opening of the Central South Atlantic and the consequent formation of the eastern Brazilian continental margin was marked by a complex history of mafic magmatism,carbonate sedimentation,and deposition of a thick salt layer.The carbonates underlying the salt layer(pre-salt carbonates)were formed in restricted lacustrine basins.Here,the timing and fluid sources of deposition,diagenetic,and hydrothermal alterations of the pre-salt carbonate rocks are defined through in-situ U-Pb dating,87Sr/86Sr,and trace element analyses of samples from the Santos Basin.The very alkaline nature of the Aptian lake(s)produced characteristically unique and widely distributed carbonate rocks such as Mg-clays with calcite spherulite and calcite crystal shrub limestones transitioning laterally and vertically into travertines formed by hydrothermal pulses during basin evolution.Hydrothermalism caused extensive replacement,dissolution,and calcite cementation.REE+Y PAAS-normalised patterns and 87Sr/86Sr ratios indicate that deposition/eo-diagenesis of the primary carbonates occurred in a lacustrine environment primarily controlled by evaporation,pH,and continental water source,with 2%–10%hydrothermal fluid input.Trace elements and Sr-isotope of travertines and burial diagenetic phases show that they are produced from a hot mixture of mafic/mantle-derived fluids and dissolution/alteration of older carbonate formations.U-Pb dating indicates that carbonate deposition occurred between 124.8±2.6 Ma and 120.0±1.6 Ma,earlier than previously proposed,followed closely by the circulation of hydrothermal fluids.Replacement and cementation ages range from 120.5±2.4 Ma to 80.4±2.4 Ma.
基金supported by the National Natural Science Foundation of China(No.42222205)the National Key Research and Development Program of China(No.2017YFC0602403)the Fundamental Research Funds for the Central Universities,CHD(No.300102273301)。
文摘Quartz trace elements are extensively employed in studying magmatic evolution,fluid evolution,and metal enrichment.The Bianjiadayuan Ag-Pb-Zn-Sn deposit is a typical magmatichydrothermal system in northeastern China,however,studies on its complex magmatic-hydrothermal evolution are limited.This study investigates the quartz from the Bianjiadayuan deposit to gain insight into the physicochemical evolution of mineralization using cathodoluminescence(CL)textures and laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS)of quartz.Five types quartz(Q1 to Q5)were identified.From Q1 in quartz porphyry to Q5 in Ag-Pb-Zn veins,the CL intensity and Ti content gradually decreases,and Ge,Ge/Ti,and Al/Ti ratios increase,indicating a temperature decline from magmatic to hydrothermal stages.The Sb content shows an opposite trend to Ti content,correlating positively with Ge content in quartz,suggesting that Sb content could also be temperature-dependent.These trace elements in quartz indicate cooling is critical for Ag mineralization.Furthermore,quartz phenocryst(Q1)from the quartz porphyry shows low Al/Ti(mostly<4)and Ge/Ti ratios(<0.04),suggesting a low degree of magmatic evolution.The Sb content in Q5 from Ag-Pb-Zn-quartz veins(>1 ppm,mostly tens of ppm)is notably higher compared to quartz in other lithologies including Sn-bearing quartz veins(<1 ppm),suggesting that Sb contents can serve as an effective indicator of Ag mineralization.
文摘This work focused on determining the physico-chemical characteristics (pH, carbon and nitrogen) and trace metal elements (TMEs) content (As, Sb, Cd, Hg, Ni, Pb, Cr, Zn) of soils in the Brazzaville city. Soil samples were taken from a depth of 0 to 20 cm using a hand auger on both banks of five tributaries of the Congo River (Djoué, Mfilou, Mfoa, Tsiémé, Djiri) that flow through the city of Brazzaville. 90 sampling points were defined, with 3 points 250 m apart on the banks and located, for each river, at three sites: upstream, midstream and downstream. Finally, 15 composite samples representative of the study area were taken. The average pH values of the water varied between 6.5 and 7.5. These pH values show that the soils studied are neutral. Total carbon content varied between 0.7% (Djiri) and 1.6% (Djoué). Total nitrogen content ranged from 0.08% (Djiri) to 0.12% (Djoué). TMEs contents varied from 0.5 to 1.8 mg/kg for Sb, from 0.5 to 2.5 mg/kg for As, from 0.1 to 0.18 mg/kg for Cd, from 4.2 to 11.3 mg/kg for Cr, from 0.07 to 0.27 mg/kg for Hg, from 0.7 to 2.4 mg/kg for Ni, from 0 to 158 mg/kg for Pb and from 16 to 105 mg/kg for Zn. The lowest TMEs levels were observed in the soils of the Djiri river, while the highest levels were observed in the soils of the Djoué and Tsiémé rivers. The ANOVA and Bonferroni test did not show significant differences in the means of the parameters measured (p > 0.05). The TMEs levels were below the accepted standards (NF U44-041), with the exception of Pb, which had high levels downstream of the Djoué. According to the pollution index values calculated using soil TME content, the soils on the banks of the Djoué river are considered polluted, while those on the banks of the Tsiémé river are moderately polluted, those on the banks of the Mfoa and Mfilou rivers are slightly polluted, and the soils on the banks of Djiri river are unpolluted.
基金supported by the National Natural Science Foundation of China,funding numbers 41690131,41572327,51874280 and 5264015.
文摘The presence of inorganic constituents in coal is controlled by different geological factors,which,in turn,affect the technological,environmental,and health impacts of the coal.The main aim of this study is to objectively assess the mineralogical and geochemical characteristics of a thickest low-rank coal seam in the Lower Indus Basin southeastern Pakistan,and further investigate different controlling factors.The analytical results of major oxides,trace elements,and rare earth elements revealed that the weathering conditions were progressively variable and moderate.The sediment source,mainly of felsic and intermediate composition,was dominated by granitic rocks.The geochemical assessment reveals different depositional factors like marine environment influenced,while transitional and freshwater sediments influenced the center of the coal peat mire.Strontium,Zinc,and several hazardous trace elements,including Cu,Ni,Cr,and Co,have higher concentrations in these coals compared to world low-rank,U.S.,and Chinese coals.The relatively higher concentration of Sr in the thick coal seam in the Lower Indus Basin,compared to other coals seams in Pakistan and the enrichment of Sr was primarily controlled by the denudation of crystalline rocks and marine influx in the coal-basin.The REY distribution pattern showed that enrichment of medium and heavy rare earth elements is higher than light rare earth elements in the coal seam.The Gd distribution pattern in the coal seam demonstrated that strong positive anomalies had a good affinity with paleo-acidic water concentration in the study area.The higher concentration of Sr and other elements enables a better assessment understanding of the coal geochemical history.
基金supported by the Korea Polar Research Institute grant(PE25100)the National Research Foundation of Korea grant funded by the Korean Government(NRF2022R1A2C3007047)supported by Korea Institute of Marine Science&Technology Promotion(KIMST)and by the Ministry of Oceans and Fisheries(RS-2023-00256677,PM23020).
文摘The measurement of trace elements in Antarctic snow is crucial for understanding historical atmospheric geochemical changes and circulation patterns.However,studies on their spatial distributions remain limited,particularly those evaluating multiple metals across several snowpits,making interpretation challenging.This study investigates the distributions and sources of trace elements-including Cd,Ba,Pb,U,Bi,V,Mn,Fe,Cu,Zn,and As-across four snowpits in the Lambert Glacier Basin,East Antarctica.The trace elements exhibit site-,element-,and season-dependent variations,with higher concentrations observed at inland sites.In contrast,δ^(18)O and ion concentrations decrease with increasing distance from the coast and elevation,underscoring the influence of marine emissions.Crustal sources primarily contributed to Ba,U,V,Mn,and Fe,while non-crustal sources predominantly contributed to Cd,Bi,Zn,Pb,Cu,and As.Positive matrix factorization(PMF)analysis indicates that trace element concentrations in Pits 2 and 3 are influenced by both crustal and non-crustal sources,while Pit 4 reflects a mixed-source influence.Pit 1(coastal site)also indicates the mixed sources with influence of a highly dynamic marine climate and environment.The PMF results reveal similarities in emission sources and atmospheric transport patterns across the snowpits,facilitating a more comprehensive interpretation of longer ice core records.Overall,this study provides valuable insights into trace element distributions and enhances our understanding of past environmental and climatic conditions.
文摘This review systematically summarizes the core advances in the field of trace elements and tumors,and clarifies the dual roles of key elements such as Zn,Cu,Fe,Se,Mn,and Ni in tumorigenesis(e.g.,DNA damage repair),tumor progression(e.g.,tumor microenvironment regulation),and therapeutic response-these elements not only possess tumor-suppressive potential but can also contribute to tumorigenesis.Meanwhile,it confirms the breakthrough value of multi-omics technologies and organoid models in deciphering the“element-cell-tumor”interaction mechanisms,which overcomes the limitations of traditional in vitro experiments and also points out the core directions for subsequent clinical research.
文摘To study the distribution of 25 elements, i.e. Be, Cd, Ce, Cr, Cu, Dy, Er,Eu, Gd, Ge, Ho, La, Lu, Mo, Nd, Pb, Pr, Sm, Sr, Tb, Tl, Tm, Y, Yb and Zn in Phytolacca, atraditional Chinese medicinal herb, collected from nine areas of P. R. China. Methods Twenty-fiveelements in Phytolacca including essential elements, toxic elements and rare earth elements intraditional Chinese medicinal herbs from different areas were analyzed by ICP-MS. Results The 25elements in Phytolacca were determined by ICP-MS under optimized conditions. The detection limitswere 0.003 -0.71 ng·mL^(-1). The recoveries were 88% - 118% . The relative standard deviations ofthe measurements were 1.7% - 13.3%. Conclusion The determined concentrations of elements inPhytolacca acinosa Roxb vary from one area to another; however, the distribution tendency ofelements in all the samples is similar. The distribution tendency of rare earth elements inPhytolacca acinosa Roxb is consistent with that in nature.
文摘The stimulative effect of trace elements on seed germination and seedling growth of Pinus tabulaeformis was tested. The experiments were carried out on seed soak and topdressing with different trace elements and varied concentrations at the nursery of Gardens Research Institute, Harbin, in 2000-2001. The experimental results showed that soaking seed with 1% and 0.2% concentrations of Mn element produced best result for seed germination, and the germination rate was increased by 9%~19% for the seeds treated with 1% concentration and 12%~14% for the seeds treated with 0.2% concentration compared with the control group. The seeds treated with boron element had lowest germination rate. For trace element topdressing, Mn and Mo elements presented good result for seedling growth and the treatment with low concentration was even better. The height or chlorophyll content of the seedlings with spray of low-concentration Mn and Mo element was much higher than that of untreated ones. In the contrast to the treating method of seed soak, topdressing (application of spraying on foliage) had evident effect on seedling growth.
基金Supported by National Natural Science Foundation of China(31172245)Major Agricultural Application Technology Innovation Project in Shandong Province(LCNZ[2014]38)~~
文摘[Objective] This study aimed to promote the combination of cultivation and livestock farming, and to explore an environment-protecting farming style. [Method]The effects of anaerobically fermented complete compound sow feed, added with Lactobacillus and Bacillus subtilis, on the chemical fractionation of copper, iron, zinc and manganese in feed and pig manure and skatole content in pig manure were investigated. [Result] Compared with those in the non-fermented feed, in the fermented feed and pig manure, the acetic acid-extractable copper, iron, zinc and manganese contents increased significantly（P0.05）, the reduced copper and iron contents increased significantly（P 0.05）, the oxidized copper and iron contents reduced significantly（P0.05）, and the residual copper contents remained unchangeable（P0.05）. The pH value of fermented feed decreased significantly（P0.05）, and that of pig manure increased significantly（P0.05）. The skatole content in pig manure decreased significantly（P 0.01）. The Lactobacillus abundance and amylase and cellulase activity increased significantly（P 0.05）. [Conclusion] The fermentation of feed changed the chemical fractionation of copper, iron, zinc and manganese in feed and pig manure, and reduced the manure odor.
基金Supported by National Natural Science Foundation of China(30960179)Program for Innovative Research Team(in Science and Technology)in University of Yunnan Province~~
文摘In order to investigate the distribution of soil available micronutrients, and provide a theoretical basis for management of fertilizing reasonably on crops, the contents of major and trace elements （P, K, Ca, Mg, Cu, Fe, Zn, and Mn） in farm- land soil collected from Yunnan Province were determined by inductively coupled plasma-mass spectrometry （ICP-MS）, the contents and distribution of major and trace elements were also studied. The results showed that the contents of available P, K were balance, available Ca, Mg were deficient, and available Cu, Fe, Zn, Mn were very plentiful. Major and trace elements distribution of different landform areas were obviously different. The contents of trace elements （Fe, Zn and Mn） of central Yunnan Red Plateau were significantly higher than those of Hengduan Mountains in western Yunnan and those of karst plateau in eastern Yunnan. The contents of available P, K, and Ca gradually declined from west to east, while the content of available Cu rose gradually from west to east. The results are reference value to elements determination and agricultural production in farmland soils.
文摘AIMS The paper studies the relationship between spleen deficiency substance,spleen deficiency and gastric cancer. METHODS We adopted the IBAS 2000 image analysis system,501B SEM with 9100/60 energy chromatic dispersing X-ray analysis instrument technique,histologic chemistry and radio-immunity means to assay the ultramicro structure,in- testinal rnetaplasia subtypes,cAMP,DNA,trace element series and their oxides of the patients' gastric mucosa. RESULTS The incidence rates of gastric cancer,incom- plete colonic intestinal metaplasia and“background lesion”of spleen deficiency with Qi stagnation patients are remarkably higher than those of spleen Qi deficiency patients(P<0.05- 0.001 ).The levels of gastric mucosa cAMP,Zn,Cu,ZnO and CuO decreased from complete to incomplete intestinal meta- plasia and from small to colonic intestinal metaplasia,while DNA increased in the above sequence(P<0.05-0.001 ).The lev- els of DNA,cAMP,Zn,Cu,ZnO and CuO in gastric mucosa of incomplete colonic intestinal metaplasia tissue are not remark- ably different from those in gastric cancer tissue. CONCLUSION Gastric diseases of spleen dificiency with Qi stagnation has the tendency of cancerization; There is a close relationship between the incidence of incomplete colonic intestinal metaplasia and gastric cancer.
基金Supported by Liaoning Natural Science Foundation Project(20062124)~~
文摘The paper was to explore the effect of trace and secondary elements on scab of cucurbits （ Cladosporium cucumerinum） and their effects on enzyme activities of cucumber plants. [ Method ] Indoor antifungd experiment and pot test was carried out to study the control effect of different trace and secondary dements on scab of cucu.rbits; after trace and secondary element compounds were sprayed for 7 d, the content of soluble protein and malondialdehyde （MDA） and the activities of peroxidase （POD） and superoxide dismutase （SOD） of cucumber leaves during seedling stage were simultaneously detected. [ Result] The inhibi- tion effects on scab of cucurbits were found in the three trace and secondary dements, especially for the CaC12 （66.9%）, and about 54.6% and 24.1% for ZnSO4 and H3 BO3 , respectively. When cucumber plants were infected by scab of cuea.rbits, the contents of MDA for all treatments were significantly decreased in cucum- ber leaves after spraying the three trace and secondary elements compared with control. The contents of soluble protein in cucumber seedling were increased by Zn- SO4 and H3 BO3 application, while the contents of POD and SOD were increased on ZnSO4 and CaCI2 treatments. The defense system of cucumber was induced and strengthened by application of the three trace and secondary elements. [ Conclusion ] The results provided the theoretical basis for practical application and research on resistance mechanism of using trace and secondary dements to control scab of eueurbits.
基金Supported by the Research Project for Postgraduate Students of Minzu University of China in 2015Scientific and Technological Cooperation Planning Project of Guizhou Province(QKJ LH[2015]7265)~~
文摘In the study, the contents of 5 trace elements including Fe, Cu, Mg, Mn and Ca were directly analyzed by flame atomic absorption spectroscopy in Gu- oshangye. The sample was subjected to microwave digestion with HNO3 and H2O2, and detected by the standard curve method. The results showed that Guoshangye contained abundant trace elements which rates of these trace elements were in the curacy and satisfactory. were necessary for human. The recovery range of 96%-103%. The method is ac-
基金Supported by Fund of Sichuan Provincial Administration of traditional Chinese Medicine(2008-12)~~
文摘[Objective] This study aimed to investigate the trace elements in Rehman- nia glutinosa Libosch. by using principal component analysis and clustering analysis. [Method] Principal component analysis and clustering analysis of R. glutinosa medicinal materials from different sources were conducted with contents of six trace elements as indices. [Result] The principal component analysis could comprehen- sively evaluate the quality of R. glutinosa samples with objective results which was consistent with the results of clustering analysis. [Conclusion] Principal component analysis and clustering analysis methods can be used for the quality evaluation of Chinese medicinal materials with multiple indices.
文摘[Objective] This study aimed to analyze the contents of trace elements in potatoes from different production areas in Qinghai Province. [Method] By flame atomic absorption spectrometry （FAAS）, the contents of various trace elements in potatoes were determined. [Result] Potatoes contain abundant trace elements such as Cu, Zn, Fe, Mn, Ca, K and Mg. To be specific, the contents of Ca, K and Mg were relatively high. [Conclusion] By using FAAS, the relative standard deviation was 1.17%-2.75% and the recovery rate was 97%-99.5%, indicating accurate and reli-able results with high precision.
文摘[Objective] This study aimed to investigate the effect of trace elements in peanut seed coating agent. [Method] Different concentrations of trace elements Fe and B were added into peanut coating agent, then the germination rate and plant height of the seeds treated by different agents were measured to decide the best formula. [Result] The germination rate and plant height of the seeds treated with seed coating agent was obviously increased. Adding trace elements Fe and B could increase the peanut yield, and 1.5% Fe and 1% B gave the best result. [Conclusion] This study will provide reference for modifying the seed coating agent formula.
基金supported by the National Basic Research Program of China(grant no.2007CB411402)
文摘Trace elements and rare earth elements（REE） of the sulfide minerals were determined by inductively-coupled plasma mass spectrometry.The results indicate that V,Cu,Sn,Ga,Cd,In,and Se are concentrated in sphalerite,Sb,As,Ge,and Tl are concentrated in galena,and almost all trace elements in pyrite are low.The Ga and Cd contents in the light-yellow sphalerites are higher than that in the brown and the black sphalerites.The contents of Ge,Tl,In,and Se in brown sphalerites are higher than that in light-yellow sphalerites and black sphalerites.It shows that REE concentrations are higher in pyrite than in sphalerite,and galena.In sphalerites,the REE concentration decreases from light-yellow sphalerites,brown sphalerites,to black sphalerites.The ratios of Ga/In are more than 10, and Co/Ni are less than 1 in the studied sphalerites and pyrites,respectively,indicating that the genesis of the Tianqiao Pb-Zn ore deposit might belong to sedimentary-reformed genesis associated with hydrothermal genesis.The relationship between LnGa and LnIn in sphalerite,and between LnBi and LnSb in galena,indicates that the Tianqiao Pb-Zn ore deposit might belong to sedimentary-reformed genesis.Based on the chondrite-normalized REE patterns,δEu is a negative anomaly（0.13-0.88）,andδCe does not show obvious anomaly（0.88-1.31）;all the samples have low total REE concentrations（〈3 ppm） and a wide range of light rare earth element/high rare earth element ratios（1.12-12.35）.These results indicate that the ore-forming fluids occur under a reducing environment.Comparison REE compositions and parameters of sphalerites,galenas,pyrites,ores,altered dolostone rocks,strata carbonates,and the pyrite from Lower Carboniferous Datang Formation showed that the ore-forming fluids might come from polycomponent systems,that is,different chronostratigraphic units could make an important contribution to the ore-forming fluids.Combined with the tectonic setting and previous isotopic geochemistry evidence,we conclude that the ore-deposit genesis is hydrothermal,sedimentary reformed,with multisources characteristics of ore-forming fluids.
基金financial support of National Key Research&Development Project of China(2018YFB0605101)National Natural Science Foundation of China(No.201706050)+1 种基金Key Project Natural Science Foundation of Tianjin(18JCZDJC39800)The Science and Technology Key Project of Tianjin(18ZXSZSF00040,18KPXMSF00080,18PTZWHZ00010)。
文摘China’s energy dependents on coal due to the abundance and low cost of coal.Coal provides a secure and stable energy source in China.Over-dependence on coal results in the emission of Hazardous Trace Elements(HTEs)including selenium(Se),mercury(Hg),lead(Pb),arsenic(As),etc.,from Coal-Fired Power Plants(CFPPs),which are the major toxic air pollutants causing widespread concern.For this reason,it is essential to provide a succinct analysis of the main HTEs emission control techniques while concurrently identifying the research prospects framework and specifying future research directions.The study herein reviews various techniques applied in China for the selected HTEs emission control,including the technical,institutional,policy,and regulatory aspects.The specific areas covered in this study include health effects,future coal production and consumption,the current situation of HTEs in Chinese coal,the chemistry of selected HTEs,control techniques,policies,and action plans safeguarding the emission control.The review emphasizes the fact that China must establish and promote efficient and clean ways to utilize coal in order to realize sustainable development.The principal conclusion is that cleaning coal technologies and fuel substitution should be great potential HTEs control technologies in China.Future research should focus on the simultaneous removal of HTEs,PM,SOx,and NOx in the complex flue gas.
基金The financial supports are greatly appreciated from the Central Public-interest Scientific Institution Basal Research Fund of China(1610322013003)the Agriculture Achievements Transformation Fund Project of the Ministry of Science and Technology of China(2010GB23260564)
文摘The purpose of the present study was to survey contents of trace elements of Cu, Mn, Fe, and Zn in the surface layer （0-20 cm） in the soil, pasture and serum of sheep in Huangcheng area of Qilian mountain grassland, China. Also the soil-plantanimal continuum was analyzed. Soil （n=300）, pasture （n=60）, and blood serum samples from sheep （n=480） were collected from Huangcheng area of Qilian mountain grassland, China. The contents of trace element in the samples were analyzed by atomic absorption spectrophotometer after digestion. The soil trace elements density distribution shows a ladder-like pattern distribution. Equations developed in the present study for prediction of Fe （R2=0.943） and Zn （R2=0.882） had significant R2 values.
基金funded by the National Key Basic Research Development Plan(Grant Agreement number 2014CB744302).
文摘Optical microscopy and scanning electron microscopy in conjunction with energy dispersed X-ray spectrometry(SEM–EDX)were used to study the minerals and the concentrations of 33 trace elements in No.6 coal from Heidaigou mine.The distributions,organic affinity and removability of 18 trace elements were studied by float-sink experiments.A determination of the maceral groups was also undertaken.A high mineral content,dominated by kaolinite,was found in No.6 coal from Heidaigou mine.The bauxite content was relatively high and it was mainly present as individual particles in fusinite lumens or was intimately intergrown with carbonate minerals.The pyrite and quartz contents were low.Some marcasite with a parallel twin structure was observed by cross-polar reflected light.A small amount of bean-like goyazite was present in the calcite.The weighted trace element content in Heidaigou formations is relatively low,which is beneficial for coal processing and utilization.The concentrations of Ga,Hg,Pb,Se,Th,Ta are relatively high compared with the average values of Chinese coals.As,Hg,Mo,Ge,Ga,Ta,Ti,W,Mn are mainly present in minerals while B,Be,Th,P,Sc,Sr,V,Y,Yb are mainly found in organic matter.As,Ge,Hg,Mo are mainly present in sulfides and Be,Th,P,Sc,Sr,Y,Yb are mainly present in inertinite.B and V are mainly present in vitrinite.The high organic affinity and the low theoretical removability of most trace elements cause difficulties in removing them during coal preparation.
