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Spatial distribution and export of nutrients and metal elements in the subterranean estuary of Daya Bay
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作者 Zhaoxi Liu Mingchen Ge +4 位作者 Qianqian Wang Xuejing Wang Kai Xiao Gang Li Hailong Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期77-86,共10页
Subterranean estuaries(STE)are important seawater-groundwater mixing zones with complex biogeochemical processes,which play a vital role in the migration and transformation of dissolved materials.In this study,we firs... Subterranean estuaries(STE)are important seawater-groundwater mixing zones with complex biogeochemical processes,which play a vital role in the migration and transformation of dissolved materials.In this study,we first investigated the spatial distributions of dissolved inorganic nitrogen(DIN),dissolved inorganic phosphorous(DIP),dissolved inorganic silicon(DSi)and metal elements(As,Ba,Cr,Cu,Fe,Mn,Ni,Pb,and Zn)in STE including upper intertidal,seepage face and subtidal zones.We then estimated submarine groundwater discharge(SGD)and associated nutrient and metal element fluxes.From the generalized Darcy’s law method,SGD was estimated to be 30.13 cm/d,which was about 7 times larger than the inflow(4.16 cm/d).The nutrient and metal fluxes from SGD were estimated to be(5.33±4.99)mmol/(m^(2)·d)for DIN,(0.22±0.03)mmol/(m^(2)·d)for DIP,(16.20±2.05)mmol/(m^(2)·d)for DSi,(1325.06±99.10)μmol/(m^(2)·d)for Fe,(143.41±25.13)μmol/(m^(2)·d)for Mn,(304.06±81.07)μmol/(m^(2)·d)for Zn,(140.21±13.33)μmol/(m^(2)·d)for Cu,(84.49±2.94)μmol/(m^(2)·d)for Pb,(37.38±5.51)μmol/(m^(2)·d)for Ba,(27.88±3.89)μmol/(m^(2)·d)for Cr,(10.10±6.33)μmol/(m^(2)·d)for Ni,and(6.25±3.45)μmol/(m^(2)·d)for As.The nutrient and metal fluxes from SGD were relatively higher than those from the inflow,suggesting that nearshore groundwater acted as the sources of nutrients and metal elements discharging into the sea.The environmental potential pollution of coastal seawater was evaluated by pollution factor index(Pi),comprehensive water quality index(CWQI),and ecological risk index(ERI).Pb mainly caused potential danger of nearshore environment with considerable contamination(Pi=5.78±0.19),heavy pollution(CWQI=4.09)and high ecological risk(ERI=18.00).This study contributed to better understanding the behavior of nutrients and metal elements and improving the sustainable management of STE under the pressure of anthropogenic activities and climate change. 展开更多
关键词 subterranean estuaries submarine groundwater discharge NUTRIENTS metal elements pollution assessment Daya Bay
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SPATIAL-TEMPORAL VARIATION OF HEAVY METAL ELEMENTS CONTENT IN COVERING SOIL OF RECLAMATION AREA IN FUSHUN COAL MINE 被引量:5
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作者 YUJun-bao LIUJing-shuang 《Chinese Geographical Science》 SCIE CSCD 2002年第3期268-272,共5页
Grid method is employed for sampling covering soil at the test field,whic h is reclamation area filled by coal mining wastes for cropland in th e Fushun coal mine,Liaoning Province,the Northeast China.The soil samp le... Grid method is employed for sampling covering soil at the test field,whic h is reclamation area filled by coal mining wastes for cropland in th e Fushun coal mine,Liaoning Province,the Northeast China.The soil samp les are taken at different locations,inclu ding three kinds of covering soil,th ree different depths of soil layers a nd four different covering ages of covering soil.The s patial-temporal variation of heavy metal element content in reclamatio n soil is stud-ied.The results indicate that the co ntent of heavy metal elements is decreasing year after year;the determin ant reason why the content of heavy metal elemen ts at 60cm depth layer is higher than t hat at 30cm depth layer and surface is fertiliz-er and manure application;the metal elements mainly come from external environment;there is no metal pollut ion coming from mother material(coal mining wastes)in plough layer of covering soil. 展开更多
关键词 covering soil heavy metal elements spatial-temporal variation RECLAMATION fushun coal mine
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Ultrasonic Nebulizer Assisted LIBS: a Promising Metal Elements Detection Method for Aqueous Sample Analysis 被引量:2
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作者 钟石磊 郑荣儿 +2 位作者 卢渊 程凯 修俊山 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第11期979-984,共6页
A newly developed approach for trace metal elements detection for aqueous samples analysis is presented in this paper. The idea of this approach is to improve ablation efficiency by transforming the liquid sample into... A newly developed approach for trace metal elements detection for aqueous samples analysis is presented in this paper. The idea of this approach is to improve ablation efficiency by transforming the liquid sample into a dense cloud of droplets using an ultrasonic nebulizer. The resulting droplets are then subjected to analysis by laser induced breakdown spectroscopy (LIBS). A purpose-built ultrasonic nebulizer assisted LIBS (UN-LIBS) system has been applied to the analysis of aqueous samples at trace levels of concentration. Experimental investigations of solution samples were carried out with various dissolved trace metal elements (Mn, Zn, Cu, Pb, Fe, Mg and Na) using this approach. The characteristics of UN-LIBS signal of the elements were investigated regarding the lifetime and S/B ratio and the calibration curves for trace metal elements analyses. The obtained LODs are comparable or much better than the LODS of the reported signal enhancement approaches when the laser pulse energy was as low as 30 mJ. The good linearity of calibration curves and the low LODs shows the potential ability of this method for metal elements analysis application. The density of the electrons was calculated by measuring the Stark width of the line of Ha. The possible mechanism of the LIBS signal enhancement of this approach was briefly discussed. 展开更多
关键词 LIBS ultrasonic nebulizer metal elements water solution MN
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Factors Controlling the Distribution of Transitional Metal Elements in Marine Hydrogenic Ferromanganese Crusts 被引量:1
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作者 JIANG Xuejun YAO De +1 位作者 LN Xuehui ZHAI Shikui 《Journal of Ocean University of China》 SCIE CAS 2009年第1期57-64,共8页
A series of selective dissolution experunents were conducted on the hydrogeinc ferromanganese crusts collected near Line Island to study the geochemistry of Mn, Fe, Cu, Co, Ni and Ti. Despite of the fact that the very... A series of selective dissolution experunents were conducted on the hydrogeinc ferromanganese crusts collected near Line Island to study the geochemistry of Mn, Fe, Cu, Co, Ni and Ti. Despite of the fact that the very close intergrowth between amorphous ferric oxyhydroxides and 6-MnO2 exists in the hydrogenic ferromanganese crusts, there is no isomorphous substitution between iron and manganese. This is because the two elements in oxides have different crystal chemistry and geochemistry, such assertion bemg in agreement with the results of selective dissolution experiments. Transitional metal elements such as Cu, Co, Ni and Ti are enriched in different phases, i.e. Ni and Co are incorporated into 6-MnO2 while Cu and Ti are incorporated into ferric oxyhy- droxides. The distributions of the elements in amorphous ferric oxyhydroxides and δ-MnO2 are controlled by the existing states of the elements in the seawater and the crystal chemistry and geochemistry of these elements/inns in oxides. 展开更多
关键词 hydrogenic ferromanganese crust selective dissolution experiments transitional metal elements DISTRIBUTION
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Main group metal elements for ambient-condition electrochemical nitrogen reduction 被引量:1
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作者 Ying Sun Yu Wang +7 位作者 Hui Li Wei Zhang Xi-Ming Song Da-Ming Feng Xiaodong Sun Baohua Jia Hui Mao Tianyi Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第11期51-70,I0002,共21页
Electrocatalytic N_(2) reduction under ambient-condition is considered to be the most appealing strategy to the conventional Haber-Bosch process for synthetic ammonia to alleviate greenhouse emissions and reduce envir... Electrocatalytic N_(2) reduction under ambient-condition is considered to be the most appealing strategy to the conventional Haber-Bosch process for synthetic ammonia to alleviate greenhouse emissions and reduce environmental pollution, mainly powered by renewable energy. Recent years, rapid advances have been gained in this attractive research field, and numerous electrocatalysts have been exploited. However, its conversion efficiency is still far behind the requirement of industrial applications owing to the breakage of the N≡N triple bond, which is an energetically challenging kinetically complex multistep reaction and the strong competing reaction of hydrogen evolution reaction. Recently, main group metal-based catalysts have been demonstrated promising application prospect for ammonia production, significantly boosting their further application in this field. However, a comprehensive review of main group metal-based catalysts towards electrochemical ammonia production applications is still lacking. In this review, the fundamentals of N_(2) reduction, such as the reaction pathways, the reaction potential and the challenges of N_(2) reduction have been comprehensively discussed. And then, the role, mechanism, and effect of each main group element-based catalysts used for N_(2) reduction (Li, K, Al, Ga, Sn, Sb, Bi, and their compounds) are systematically summarized. Finally, several state-of-the-art strategies to promote their NRR catalytic performance, as well as the existing problems and prospects are put forward. This review is expected to guide the design and establishment of more efficient electrocatalytic N_(2) reduction systems based on main group metal elements in the future. 展开更多
关键词 N2 reduction Main group metal elements Challenges and strategies
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Investigation on the Quality of Irrigation Water in Southern Anhui and the Effects of Metal Elements in Irrigation Water on the Coke Sweet Aroma Style of Tobacco Leaves 被引量:1
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作者 Yakui CHEN Xiangzhou DONG +1 位作者 Dengwen GE Qifa ZHU 《Agricultural Biotechnology》 CAS 2020年第6期83-87,共5页
[Objectives]The effects of metal elements in irrigation water in the tobacco areas of southern Anhui on the coke sweet aroma of tobacco leaves was determined.[Methods]53 representative areas for tobacco planting in so... [Objectives]The effects of metal elements in irrigation water in the tobacco areas of southern Anhui on the coke sweet aroma of tobacco leaves was determined.[Methods]53 representative areas for tobacco planting in southern Anhui were selected,and the quality of irrigation water,especially the content of metal elements,was investigated.[Results]The contents of micro(medium)elements in the irrigation water were too low to have a significant effect on the formation of the coke sweet aroma style of tobacco leaves.The contents of Mg,Ca and Zn were 0.7-8.0,<40 and 0.002-0.029 mg/L,respectively.The heavy metal contents of the irrigation water and other basic control items all met corresponding national standards.Furthermore,the tobacco planting experiment under controlled irrigation using paddy soil in the greenhouse proved that Zn was a negative correlation factor for forming the coke sweet aroma style of tobacco and the threshold value was≥10 mg/L in the irrigation water.Meanwhile,Mg was a positive correlation factor and the content of Mg to promote the coke sweet aroma style should be maintained at 40-90 mg/L.Ca and Mg had a synergistic effect,which was mainly appropriate for acid paddy soils.[Conclusions]This study improves the quality and yield of the coke sweet aroma of tobacco leaves,and has important theoretical and practical value for the formation of a popular agronomic control method. 展开更多
关键词 Irrigation water metal elements Burned sugar aroma style Effect
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Migration of Heavy Metal Elements in Reclaimed Irrigation Water-Soil-Plant System and Potential Risk to Human Health 被引量:1
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作者 Zixi LIU Juncang TIAN +3 位作者 Wangcheng LI Lian TANG Jie WANG Haiyan GAO 《Asian Agricultural Research》 2021年第10期41-47,53,共8页
[Objectives]To study the impact of heavy metal pollution of soil and plants during the process of reclaimed water for irrigation of green land in arid areas and the potential health risks to humans during use.[Methods... [Objectives]To study the impact of heavy metal pollution of soil and plants during the process of reclaimed water for irrigation of green land in arid areas and the potential health risks to humans during use.[Methods]Taking Zhongwei City in Ningxia,a typical arid area,as the research area,the irrigation water,soil and green grass in the reclaimed water irrigation region and the original green water irrigation region were sampled,the heavy elements Hg,As,Zn,Pb,Cd,Cr were detected,and the Nemerow method,biological absorption coefficient,and health risk assessment were employed to evaluate the degree of soil pollution,plant absorption capacity,and human health risks.[Results]Compared with the original green water,the Hg,Cd,and Cr pollution of the reclaimed water irrigated green land was higher,the As,Zn,Pb pollution was lower,and the content of Hg and Cd was higher than the environmental background values of soil in Ningxia;the Cr content exceeded the risk intervention values of the first type of land in the Soil Environmental Quality—Risk Control Standard for Soil Contamination of Development Land(GB 36600-2018).Compared with the original green water irrigation region,it is found that the reclaimed water irrigation reduced the heavy metal pollution of the soil to a certain extent.The heavy metal content of tall fescue grass(Festuca arundinacea)in the reclaimed water irrigation region was Zn,Cr,Pb,As,Cd,and Hg from high to low;the order of the biological absorption coefficient was Cd>As>Zn>Pb>Hg>Cr;irrigation water exerted a certain effect on the content of heavy metals in plants and the biological absorption coefficient through the soil.Using the health risk assessment method recommended by Environmental Protection Agency of the United States of America(USEPA),it was found that the reclaimed water has the highest risk through the inhalation route,and the occupational population has a higher risk of skin contact with soil and plants.[Conclusions]This study is intended to provide data support and theoretical basis for the environmental safety risk research of the application of reclaimed water in arid areas to urban greening. 展开更多
关键词 Reclaimed water irrigation Water-soil-plant system Migration of heavy metal elements Health risk assessment
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Review Study on the Accumulation and Release of Trace Metal Elements on Aluminum Containing Sediments in Drinking Water Distribution System 被引量:1
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作者 Xiaoni ZHANG Jinghua MENG +2 位作者 Li CHEN Huanhuan ZUO Wendong WANG 《Research and Application of Materials Science》 2020年第1期34-38,共5页
Accumulation and releasing of trace metal elements on aluminum containing sediments of inner drinking water pipe is discussed,as studied from five variations effecting:raw water quality,chemical reagents,solution pH a... Accumulation and releasing of trace metal elements on aluminum containing sediments of inner drinking water pipe is discussed,as studied from five variations effecting:raw water quality,chemical reagents,solution pH and drinking water flow condition.In order to decrease the release of trace metal elements,and to ensure the pipe operation and human safety,water quality adjustment is suggested to avoid aluminum containing sediments formation in drinking distribution system.The maximum amounts of accumulation of common trace metal elements are given.Future trends of development in this field are also proposed. 展开更多
关键词 drinking water distribution system aluminum containing sediments trace metal elements ACCUMULATION RELEASE
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Retention Factors for Trace Metal Elements in Solid Phase and Applicable Adsorption Models: Case of <i>Moringa oleifera</i>
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作者 Mariette Désirée Yehe Edwige Odoh +2 位作者 Patrick Grah Atheba Joel Cyriaque Dadje Gildas Komenan Gbassi 《Open Journal of Physical Chemistry》 2021年第3期182-195,共14页
<i><span style="font-family:;" "=""><i></i></span><i><span style="font-family:;" "="">Moringa oleifera</span></i>... <i><span style="font-family:;" "=""><i></i></span><i><span style="font-family:;" "="">Moringa oleifera</span></i><i><span style="font-family:;" "=""></span></i></i><span style="font-family:;" "=""> is an edible plant cultivated throughout the tropical belt. It belongs to the family Moringaceae and is one of its 14 known species. This paper presents a synthesis of the main factors responsible for the retention of trace metal elements (TMEs) by </span><span style="font-family:;" "=""><i></i></span><i><i><span style="font-family:;" "="">Moringa oleifera</span></i><i><span style="font-family:;" "=""></span></i></i><span style="font-family:;" "=""> seed powder, a natural adsorbent. The five main factors studied are metal concentration, solution pH, adsorbent particle size, adsorbent dose and adsorbent/adsorbate contact time. Through these factors, we present the optimal conditions for removal of these TMEs, as well as adsorption isotherm models appropriate for the conditions of retention of these metal cations by the adsorbent. The times of 20 min (GD) and 50 min (GND) are the equilibrium times obtained in our study. An optimal adsorbent mass (GD and GND powders) of 4.5 g was found. 20</span><span style="font-family:;" "="">%</span><span style="font-family:;" "=""> to 97% abatement is observed for average pH values between 6 and 8. The coefficients of determination (R2) obtained (0.972</span><span style="font-family:;" "="">,</span><span style="font-family:;" "=""> 0.963</span><span style="font-family:;" "="">,</span><span style="font-family:;" "=""> 0.991 and 0.799) during the isotherm experiments carried out at 20</span><span style="font-family:;" "="">°</span><span style="font-family:;" "="">C, 30</span><span style="font-family:;" "="">°</span><span style="font-family:;" "="">C, 40</span><span style="font-family:;" "="">°</span><span style="font-family:;" "="">C and 50</span><span style="font-family:;" "="">°</span><span style="font-family:;" "="">C are close to 1. Also, the separation factor (R<sub>L</sub>), an essential characteristic of the Langmuir isotherm whose values are between 0 and 1, attest to the applicability of the Langmuir isotherm model to fit the experimental data of copper adsorption by Moringa powders.</span><span style="font-family:;" "=""> In this paper, we are particularly interested in the following TMEs (Mn, Ni, Cr, Cu, Cd, Co, Pb, Fe, Zn, Ag).</span> 展开更多
关键词 Moringa oleifera ADSORPTION Trace metal elements (TMEs)
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Anomalous Concentrations of Rare Metal Elements, Rare-scattered(Dispersed) Elements and Rare Earth Elements in the Coal from Iqe Coalfield, Qinghai Province, China 被引量:12
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作者 SUN Yuzhuang ZHAO Cunliang +1 位作者 LI Yanheng WANG Jinxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第1期229-241,共13页
Total of 23 bench samples were taken from the No. 7 Coal of Iqe Coalfield, Qinghai Province, China, following Chinese Standard Method GB/T 482-2008 (2008). These samples were analyzed by powder X-ray diffraction (... Total of 23 bench samples were taken from the No. 7 Coal of Iqe Coalfield, Qinghai Province, China, following Chinese Standard Method GB/T 482-2008 (2008). These samples were analyzed by powder X-ray diffraction (XRD), inductively coupled plasma mass spectrometry (ICP- MS) and X-ray fluorescence (XRF). The results indicate that the No. 7 Coal belongs to a low rank (Ro.ran =0.659%) and high-ash coal (40.54%). Compared to common Chinese and world low-rank coals, the lqe coal contains anomalous concentrations of rare metal elements, rare-scattered (dispersed) elements and rare earth elements. The highest contents of Rb, Cs, Ga and REY reach to 180, 26, 37, and 397 ppm, respectively. Their average contents of these elements are 10.9, 15, 4.8 and 3.5 times higher than those of world coals, respectively. Minerals in the coal include kaolinite, quartz, muscovite, siderite, and traces of rutile, and brookite. Kaolinite could be main host minerals of Rb, Cs, Ga and REY. The anomalous rare element Rb and Cs accumulation in the Iqe coal is related to both organic and inorganic matter. The REY concentrations may be related to circulation of thermal solutions, contained or sorbed by clayey particles, and organic matter as well. 展开更多
关键词 rare metal element rare-scattered elements rare earth element Iqe Coalfield QinghaiProvince
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Evaluation on environmental quality for heavy metal elements of Xihe soil 被引量:1
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作者 Aijun WU 《Global Geology》 2008年第4期209-213,共5页
According to "Environmental quality standard for soil" and using As,Cd,Cr,Cu,Hg,Ni,Pb,Zn elements as evaluation index,the author evaluated soil environmental quality in Xihe area of Shenyang.The results show... According to "Environmental quality standard for soil" and using As,Cd,Cr,Cu,Hg,Ni,Pb,Zn elements as evaluation index,the author evaluated soil environmental quality in Xihe area of Shenyang.The results show that the soil in Xihe area is polluted rifely by heavy metal elements.The polluted areas are mainly distributed near the upstreams of Xihe River,Shenxin River and Shenliao irrigation canal.There exist large distinctions among the heavy metal elements to the pollution degree.Cd pollution area is the biggest and the most serious in pollution degree. 展开更多
关键词 Xihe SOIL heavy metal element environmental quality
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Contents of Trace Metal Elements in Cow Milk Impacted by Different Feedstuffs
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作者 Song Ren-ju Tong Hui-li +1 位作者 Huang Jian-guo Gao Xue-jun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第3期54-61,共8页
Feedstuff intake plays key role in impacting the yield and quality of milk. In this study, we discussed the contents of trace metal elements in cow milk impacted by different feedstuffs. We detected the contents of Pb... Feedstuff intake plays key role in impacting the yield and quality of milk. In this study, we discussed the contents of trace metal elements in cow milk impacted by different feedstuffs. We detected the contents of Pb, Cd, As, Cu, Mg, Ca, Fe and Zn in different feedstuffs and milk by atomic absorption spectrophotometry. The determinations of Pb, Cd and As contents were by graphite furnace A_AS and Cu, Mg, Ca, Fe and Zn was by flame atomic absorption spectrometry. The results showed that Pb, Cd, As and Cu presented in feedstuffs, but Pb, Cd and As were lowly detected in milk samples, and Cu was not detected in milk samples. The content of Mg in concentrates was lower than that in forages. However, the content of Mg in milk from concentrate feed was higher than that in forage feed. This suggested that the utilization of Mg in concentrate feed was higher than that in forage feed. The contents of Ca and Zn were opposite to Mg, and the utilization of Ca and Zn in forage feed was higher than that in concentrate feed. There was no obviously change law of Fe in different feedstuffs and milk samples. The relationship between the contents of trace metal elements in milk to feedstuffs would provide a theoretical basis for dairy farming. It would be useful for improving the milk yield and milk quality of dairy production. 展开更多
关键词 feedstuff cow milk trace metal element CONTENT
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Annual Fluxes of Heavy Metal Elements in Atmospheric Dry and Wet Depositions in the Pearl River Delta Economic Region, Guangdong Province
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作者 Lu Lu Cen Kuang 《Journal of Geoscience and Environment Protection》 2021年第5期8-14,共7页
<div style="text-align:justify;"> There are 158 sampling points to be set up in the Pearl River delta economic region. The collecting period is mostly one year, namely, from July 2007 to July 2008. The... <div style="text-align:justify;"> There are 158 sampling points to be set up in the Pearl River delta economic region. The collecting period is mostly one year, namely, from July 2007 to July 2008. The eight heavy metal elements of Cr, Ni, Cu, Pb, Zn, As, Hg, and Cd in 474 dry and wet deposition samples were tested in terms of the standard procedures. Their average annual fluxes have no obvious difference between dry deposition and wet deposition. So these elements might be at an equilibrium or quasi-equilibrium state between dry deposition and wet deposition. </div> 展开更多
关键词 Atmospheric Dry and Wet Deposition Heavy metal Element FLUX Pearl River Delta Economic Region
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Sources, enrichment mechanisms, and resource effects of rare metal elements-enriched geothermal springs in Xizang, China
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作者 Fei XUE Hongbing TAN +1 位作者 Xiying ZHANG Jinbao SU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第11期3476-3499,共24页
Rare metals such as lithium(Li), rubidium(Rb), and cesium(Cs) are strategically crucial mineral resources for the development of emerging industries in China. Ensuring a stable long-term supply of these resources is e... Rare metals such as lithium(Li), rubidium(Rb), and cesium(Cs) are strategically crucial mineral resources for the development of emerging industries in China. Ensuring a stable long-term supply of these resources is essential. The geothermal systems in Xizang, China are well-developed, with a wide distribution of various types. Most high-temperature geothermal systems in Xizang are exceptionally enriched in rare metal elements(RMEs) and have the potential to become a new source of rare metals to secure China's strategic mineral resource supply in the future. A close relationship also exists between the geothermal system and the special salt lake resources on the Tibetan Plateau. Geothermal springs thus play a key role in the migration and enrichment of RMEs from deep to shallow parts of the crust, in the transition between endogenous and exogenous mineralization, and source-to-sink processes. However, the mechanisms of element enrichment and evolution in these springs have not been systematically discussed, and many theoretical issues remain to be investigated. Based on summarizing and analyzing previous research, this study employs hydrochemical and isotopic geochemistry methods to investigate typical geothermal springs across Xizang and explore the anomalous enrichment mechanism of RMEs, and the resource effects of geothermal springs. Comprehensive analysis shows that the total dissolved solids(TDS) and hydrochemical types of geothermal springs are similar to those of major geothermal fields worldwide, but the Tibetan springs are abnormally rich in Li(averaging5.48 mg/L), Rb(averaging 0.75 mg/L), and Cs(averaging 3.58 mg/L), which are hundreds to thousands of times more concentrated than natural waters. The distribution of these enriched geothermal springs is controlled by the Yarlung Zangbo suture zone and the extended N-S trending rifts, especially in the intersection zone of the two, where the geothermal springs are the most enriched. Based on the spatial distribution, isotopic, and elemental geochemistry, the RMEs enriched in Tibetan geothermal springs are mainly derived from the magmatic-hydrothermal fluids generated by the partial melting of the subducted Indian plate under the Eurasian continent. These fluids not only maintain geothermal activities as a heat source but also participate in the material cycle of the geothermal spring as a material source. Against the background of regional crustal enrichment in RMEs,incompatible elements such as Li, Rb, and Cs are gradually enriched in magmatic-hydrothermal processes including partial melting in the source, magmatic differentiation, and hydrothermal fluid exsolution, and some ore-forming elements are further extracted from surrounding rocks through deep high-temperature water-rock interactions. Eventually, an eruption occurs, and these fluids move to the surface to form a geothermal spring rich in RMEs. With the drainage of geothermal springs, the RMEs are continuously transported to the lake basin by surface runoff and continue to concentrate and evolve into salt lake brines under an extremely arid climate environment, constituting an endogenous source and exogenous accumulation salt lake metallogenic model. This comprehensive explanation of the sources, migration, enrichment mechanisms, and resource effects of geothermal springs will deepen the understanding of rare metal mineralization processes, and aid in the advancement of theoretical models for key rare metal mineral resources in various geological bodies of the Tibetan Plateau, significantly expanding exploration scopes and accurately assessing the resource potential of RMEs. 展开更多
关键词 Geothermal springs Rare metal elements Enrichment mechanisms Salt lakes Tibetan Plateau
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Trace metal elements: a bridge between host and intestinal microorganisms 被引量:5
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作者 Yong Ma Yanquan Fei +3 位作者 Sujuan Ding Hongmei Jiang Jun Fang Gang Liu 《Science China(Life Sciences)》 SCIE CAS CSCD 2023年第9期1976-1993,共18页
Trace metal elements, such as iron, copper, manganese, and zinc, are essential nutrients for biological processes. Although their intake demand is low, they play a crucial role in cell homeostasis as the cofactors of ... Trace metal elements, such as iron, copper, manganese, and zinc, are essential nutrients for biological processes. Although their intake demand is low, they play a crucial role in cell homeostasis as the cofactors of various enzymes. Symbiotic intestinal microorganisms compete with their host for the use of trace metal elements. Moreover, the metabolic processes of trace metal elements in the host and microorganisms affect the organism's health. Supplementation or the lack of trace metal elements in the host can change the intestinal microbial community structure and function. Functional changes in symbiotic microorganisms can affect the host's metabolism of trace metal elements. In this review, we discuss the absorption and transport processes of trace metal elements in the host and symbiotic microorganisms and the effects of dynamic changes in the levels of trace metal elements on the intestinal microbial community structure. We also highlight the participation of trace metal elements as enzyme cofactors in the host immune process. Our findings indicate that the host uses metal nutrition immunity or metal poisoning to resist pathogens and improve immunity. 展开更多
关键词 trace metal elements intestinal microorganisms host immunity metal metabolism
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Advances in osseointegration of biomimetic mineralized collagen and inorganic metal elements of natural bone for bone repair 被引量:2
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作者 Wenbo Zhu Chao Li +5 位作者 Mengxuan Yao Xiumei Wang Juan Wang Wei Zhang Wei Chen Hongzhi Lv 《Regenerative Biomaterials》 SCIE EI CSCD 2023年第1期808-829,共22页
At this stage,bone defects caused by trauma,infection,tumor,or congenital diseases are generally filled with autologous bone or allogeneic bone transplantation,but this treatment method has limited sources,potential d... At this stage,bone defects caused by trauma,infection,tumor,or congenital diseases are generally filled with autologous bone or allogeneic bone transplantation,but this treatment method has limited sources,potential disease transmission and other problems.Ideal bone-graft materials remain continuously explored,and bone defect reconstruction remains a significant challenge.Mineralized collagen prepared by bionic mineralization combining organic polymer collagen with inorganic mineral calcium phosphate can effectively imitate the composition and hierarchical structure of natural bone and has good application value in bone repair materials.Magnesium,strontium,zinc and other inorganic components not only can activate relevant signaling pathways to induce differentiation of osteogenic precursor cells but also stimulate other core biological processes of bone tissue growth and play an important role in natural bone growth,and bone repair and reconstruction.This study reviewed the advances in hydroxyapatite/collagen composite scaffolds and osseointegration with natural bone inorganic components,such as magnesium,strontium and zinc. 展开更多
关键词 mineralized collagen bone defect reconstruction inorganic metal elements clinical applications
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Health risk assessment of heavy metal pollution in groundwater of a karst basin,SW China
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作者 Fu-ning Lan Yi Zhao +1 位作者 Jun Li Xiu-qun Zhu 《Journal of Groundwater Science and Engineering》 2024年第1期49-61,共13页
To investigate the presence of metal elements and assess their health risk for the populace in the Nandong Underground River Basin(NURB),we conducted an analysis of eleven common heavy metals in the water body.A Healt... To investigate the presence of metal elements and assess their health risk for the populace in the Nandong Underground River Basin(NURB),we conducted an analysis of eleven common heavy metals in the water body.A Health risk assessment(HRA)model was employed to analyze 84 water samples from the NURB.The detection results revealed the following order of heavy metals concentrations:Fe>Al>Mn>Zn>As>Cd>Pb>Cr>Ni>Cu>Hg.Correlation analysis indicated a certain similarity in material source and migration transformation among these eleven metal elements.Our study identified that the health risks for local residents exposed to metal elements in the water of NURB primarily stem from carcinogenic risk(10^(−6)–10^(−4)a^(−1))through the drinking water pathway.Moreover,the health risk of heavy metal exposure for children through drinking water was notably higher than for adults.The maximum health risks of Cr in both underground and surface water exceeded the recommendation standard(5.0×10^(−5)a^(−1))from ICRP,surpassing the values recommended by the Swedish Environmental Protection Agency,the Dutch Ministry of Construction and Environment and the British Royal Society(5.0×10^(−6)a^(−1)).The results of the health risk assessment indicate that Cr in the water of NURB is the primary source of carcinogenic risk for local residents,followed by Cd and As.Consequently,it is imperative to control these three carcinogenic metals when the water was used as drinking water resource. 展开更多
关键词 Water Pollution Correlation Analysis Toxicity of Heavy metal elements Underground River Basin Carcinogenicity Potential
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Predictive Study of Trace Metal Pollution of Gold Panning Sites in Birimian Formations: Case of the Yaouré Furrow (Côte d’Ivoire)
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作者 Tonga Paul Tiemoko Gbele Ouattara Kouassi Ernest Ahoussi 《Open Journal of Applied Sciences》 2024年第7期1691-1714,共24页
The present study was carried out on small-scale gold mining sites in the Yaouré region of Côte d’Ivoire. This region is geologically representative of the Birimian formations (2.1 Ga) of West Africa. The a... The present study was carried out on small-scale gold mining sites in the Yaouré region of Côte d’Ivoire. This region is geologically representative of the Birimian formations (2.1 Ga) of West Africa. The aim is to determine the potentially toxic trace metals (TMEs) generated by these sites, with a view to preventing possible contamination and/or metal pollution of the waters that provide fish products for local populations. To this end, a sampling campaign was carried out, resulting in the collection of 20 mining waste samples analyzed by X-ray fluorescence spectrometry (XRF) and 10 by X-ray diffractometer (XRD). The XRF analysis detected 06 predominant TMEs: arsenic, chromium, copper, nickel, zinc and vanadium. Statistical analysis was carried out to determine the distributions and correlations between these ETMs. To assess contamination and/or pollution levels, the following indices were calculated on the basis of reference concentrations of upper continental crust MTEs: Enrichment Factor, Geo-accumulation Index, Concentration Factor, Degree of contamination and those related to ecological risks. The results of statistical analyses and indices have shown that arsenic and chromium are the most predominant and can be, depending on the chemical form, potentially more toxic. The results of the DRX analysis show the occurrence of several minerals carrying these two MTEs, especially that of a rare mineral, Stenhuggarite, an arsenic oxide linked to hydrothermal veins. The majority of gold mining operations in West Africa are located in the birimian zone, hence the need for environmental monitoring by the relevant authorities, to prevent potential ecological risks to water and possibly health risks via the food chain. 展开更多
关键词 Small-Scale Mining metallic Trace elements Mining Discharges CONTAMINATION POLLUTION CONTAMINATION POLLUTION Index
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Organic/ Inorganic Occurrence of Metallic Elements of the Black Shale-Hosted Baiguoyuan Silver-Vanadium Deposit in Xingshan, Hubei 被引量:4
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作者 ZHUANG Hanping LU Jialan +4 位作者 FU Jiamo LIU Jinzhong REN Chigang ZOU Degang TIAN Weizhi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1998年第3期299-307,共9页
: By means of kerogen purification, the proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA), the authors have studied the organic/inorganic occurrence modes of the metallic element... : By means of kerogen purification, the proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA), the authors have studied the organic/inorganic occurrence modes of the metallic elements of the Baiguoyuan silver-vanadium deposit hosted in black shale in Hubei Province, China. The result shows that Au, Hg and Ta have a strong tendency to occur organically, with more than 70% of these elements being associated organically. Se, Ga, Ag and Hf are partly associated with organic matter, with more than 20% of them occurring organically. Compared with the above elements, Zn, Cu, As and Sb are weakly associated organically, and tend to be enriched in kerogen. However, Mn, Th, U, V, Co, Cr, AI, Fe and Sc usually occur inorganically. Of the rare earth elements (REE), La, Ce, Tb, Dy, Yb and Lu have stronger ability to be associated with organic matter than Sm and Eu. 展开更多
关键词 Baiguoyuan black shale-hosted silver-vanadium deposit organic matter metallic elements occurrence modes
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Level of Contamination of Fishponds Water in Pesticide Residues and Metallic Trace Elements (Pb, Cd, As, Hg): Case of Fishponds of ZEPREGUHE (Daloa, Côte d’Ivoire)
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作者 Kacou Alain Paterne Dalogo Ano Guy Serge Ehouman +3 位作者 James Halbin Kouadio David Leonce Kouadio Edi Jean Frejus Ehui Karim Sory Traore 《Journal of Agricultural Chemistry and Environment》 CAS 2022年第4期307-317,共11页
Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs... Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs) or to the persistence in the environment and in the form of pesticide residues from human activities. The objective of this work is to evaluate, on the one hand, the levels of identified pesticide residues and, on the other hand, those of researched TMEs (lead, cadmium, mercury and arsenic) in the waters of ponds used for fish farming in Zépréguhé, a locality located 9 km from the town of Daloa in the centre-west of C&ocirc;te d’Ivoire. The dosage of the samples carried out by means of a gas chromatograph coupled to a mass spectrometer (GC/MS) made it possible to detect nine (9) pesticide molecules, including eight (8) organochlorines and a single molecule from the pyrethroid family, obtained from the detection limit of 0.006 μg/L and the quantification limit of 0.018 μg/L. The maximum average concentration was obtained with α-endosulfan for a content reaching 0.8038 μg/L and well above the maximum admissible concentration of 0.1 μg/L. The TMEs were quantified using an atomic absorption spectrophotometer (AAS). Arsenic is the most abundant metal with an average concentration of 9.497 μg/L. With the exception of lead, these measured levels are above the acceptable limit values for freshwater. This study showed that human activities such as the use of fertilisers and plant protection products in plantations, sand extraction and road traffic have a negative impact on the quality of the water in ponds used for fish breeding. 展开更多
关键词 Fishpond Water metallic Trace elements Pesticide Residues Maximum Residue Levels
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