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Corrosion behavior of pure metals(Ni and Ti)and alloys(316H SS and GH3535)in liquid GaInSn 被引量:1
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作者 Jian-Hui Yu Hong-Xia Xu +3 位作者 Xiang-Xi Ye Bin Leng Han-Xun Qiu Xing-Tai Zhou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期70-83,共14页
In this study,the interactions between a Ga-based liquid metal,GaInSn,and several metal materials,including pure metals(Ni and Ti)and alloys(316H stainless steel(SS)and GH3535),at 650℃were investigated.The aim was to... In this study,the interactions between a Ga-based liquid metal,GaInSn,and several metal materials,including pure metals(Ni and Ti)and alloys(316H stainless steel(SS)and GH3535),at 650℃were investigated.The aim was to evaluate the corrosion performance and select a suitable candidate material for use as a molten salt manometer diaphragm in thermal energy storage systems.The results indicated that the alloys(316H SS and GH3535)exhibited less corrosion than pure metals(Ni and Ti)in liquid GaInSn.Ga-rich binary intermetallic compounds were found to form on the surfaces of all the tested metal materials exposed to liquid GaInSn,as a result of the decomposition of liquid GaInSn and its reaction with the constituent elements of the metal materials.The corrosion mechanism for all the tested materials exposed to liquid GaInSn was also investigated and proposed,which may aid in selecting the optimal candidate material when liquid GaInSn is used as the pressure-sensing medium. 展开更多
关键词 metal materials Liquid GaInSn CORROSION Intermetallic compounds Thermal energy storage systems
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From Topological Nodal-Line Semimetals to Quantum Spin Hall Insulators in Tetragonal SnX Monolayers(X=F,Cl,Br,I)
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作者 朱晔 赵宝 +3 位作者 薛阳 徐玮 徐文婷 杨中芹 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第6期98-111,共14页
Two-dimensional(2D)topological materials have recently garnered significant interest due to their profound physical properties and promising applications for future quantum nanoelectronics.Achieving various topologica... Two-dimensional(2D)topological materials have recently garnered significant interest due to their profound physical properties and promising applications for future quantum nanoelectronics.Achieving various topological states within one type of materials is,however,seldom reported.Based on first-principles calculations and tightbinding models,we investigate topological electronic states in a novel family of 2D halogenated tetragonal stanene(T-SnX,X=F,Cl,Br,I).All the four monolayers are found to be unusual topological nodal-line semimetals(NLSs),protected by a glide mirror symmetry.When spin-orbit coupling(SOC)is turned on,T-SnF and TSnCl are still ascertained as topological NLSs due to the remaining band inversion,primarily composed of Sn pxy orbitals,while T-Sn Br and T-SnI become quantum spin Hall insulators.The phase transition is ascribed to moving up in energy of Sn s orbitals and increasing of SOC strengths.The topology origin in the materials is uniformly rationalized through elementary band representations.The robust and diverse topological states found in the 2D T-SnX monolayers position them as an excellent material platform for development of innovative topological electronics. 展开更多
关键词 TOPOLOGICAL metals quantum
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Analysis and Assessment on the Heavy Metals in a Severely Degraded Subtropical Red Soil Region
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作者 Fang Wang Yun Zhou +5 位作者 Xiangping Fu Yuxiao Zhao Yiyao Wen Xintao Cui Shunbao Lu Yanjie Zhang 《American Journal of Plant Sciences》 CAS 2024年第2期110-121,共12页
5 different forests of Pinus massoniana, Schima superba, Liquidambar formosana, P. massoniana × S. superba, P. massoniana × L. formosana as the research object were set up to study the Cr, Cu and Zn content ... 5 different forests of Pinus massoniana, Schima superba, Liquidambar formosana, P. massoniana × S. superba, P. massoniana × L. formosana as the research object were set up to study the Cr, Cu and Zn content of degraded red soil region in subtropics. The soil heavy metal pollution degree was evaluated by national environmental quality standard (II class). The results showed that three soil metals of P. massoniana × S. superba were the highest, and the soil metals enrichment ability was strong. The order of single factor pollution index of metal elements was Cu (1.38) > Cr (0.81) > Zn (0.42), and moderately pollution, pollution warning and no pollution, respectively. There was no significant correlation between three soil heavy metals and soil total carbon (TC), total nitrogen (TN) and total phosphorus (TP). These results suggested that the accumulation of heavy metal elements was not derived from the parent material of soil. There was a significant positive correlation between the three metal elements which indicated that the sources of the three elements were similar. The structural equation model showed that the direct and indirect effects among the influencing factors ultimately affected the activity of heavy metals by cascade effects. 展开更多
关键词 Subtropical Forest Type Degraded Red Soil Heavy metals Pollution Evaluation
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Microplastic and Heavy Metals Distributions in Urban Rivers Sediments,China
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作者 SONG Dandan SHANG Yujun +4 位作者 WANG Xiuli ZHUANG Yuwei GUO Hui BI Shuping HU Jianjun 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期1015-1025,共11页
This study investigated the distribution of microplastics and heavy metals,along with the interaction between the two in the sediments of urban rivers in China.Results showed that the abundance of microplastics ranged... This study investigated the distribution of microplastics and heavy metals,along with the interaction between the two in the sediments of urban rivers in China.Results showed that the abundance of microplastics ranged from 2412±187.5 to 7638±1312items kg^(-1)dry sediment across different survey stations,with an average abundance at(4388±713)items kg^(-1)dry sediment.Upon further categorization,it was found that transparent fragments were the primary color and type of microplastics present.The potential ecological risk index(RI)of heavy metals in sediments suggested a low level of ecological risk within a majority of the urban rivers studied.Cd was identified as the main potential ecological risk factor in the sediments of the studied areas.There was a relatively good significant linear relationship between the RI of heavy metals and the abundance of microplastics,bolstering the linkage between these two environmental pollutants.However,the concentrations of heavy metals in microplastics were not dependent on their corresponding contents in sediments.In fact,the concentration of Cu,Cd,and As in microplastics were higher than those in the sediments.This finding confirmed that microplastics could serve as carriers of heavy metals and introduce potential risks to aquatic wildlife and human through the food chain. 展开更多
关键词 microplastic heavy metals risk assessment river sediments
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Accumulation of Heavy Metals in Maga-Pouss Rice Fields (Far-North Region, Cameroon) and Transfer to Rice Grains
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作者 Diane Madomguia Gilbert Bello Basokdou +3 位作者 Kalieu W. Appoline Isabelle Patrice Kuitekam Dongo Edouard Nya Serge Hubert Zebaze Togouet 《Agricultural Sciences》 2024年第3期311-326,共16页
Monitoring of heavy metals contamination of agricultural products and their transfer and bioaccumulation in crops like rice has become a hot topic worldwide over the last two decades. The present study was carried out... Monitoring of heavy metals contamination of agricultural products and their transfer and bioaccumulation in crops like rice has become a hot topic worldwide over the last two decades. The present study was carried out to determine the accumulation of heavy metals in rice fields and their transfer to rice grains. Soil, irrigation water and rice grains samples were gathered in Maga-Pouss, Far-North, Cameroon. Concentrations of six heavy metals (lead, cadmium, zinc, copper, iron and mercury) were evaluated by Atomic Absorption Spectrophotometer (AAS). Mercury was not detected in this study. Average concentrations of metals were in this order (in mg/kg): Fe (188.60 ± 97.06) > Pb (63.63 ± 7.11) > Cd (2.59 ± 0.29) > Zn (1.10 ± 1.05) > Cu (0.80 ± 0.73) in water and Pb (105.50 ± 31.11) > Fe (105.50 ± 31.11) > Cu (45.93 ± 14.39) > Zn (22.52 ± 6.40) > Cd (3.15 ± 0.49) in soil. Water in Maga-Pouss rice fields appears to be more harmful than the soil, notably for lead, cadmium and copper. In rice grains, heavy metals were found in this order (mg/kg): Fe (188.01 ± 82.62) > Cu (27.20 ± 0.00) > Zn (23.61 ± 12.42) > Pb (19.50 ± 19.91) > Cd (2.02 ± 1.05). The mean bioconcentration factor (BCF) of metals from soil to rice grains was in the following order: Fe (2.60) > Zn (1.05) > Cd (0.64) > Cu (0.59) > Pb (0.18). From water to rice grains, the order is: Cu (37.26) > Zn (22.49) > Cd (6.97) > Pb (2.74) > Fe (1.94). Rice field pH and electrical conductivity favored the uptake of lead, copper and cadmium by rice grains. The findings of this study will be good documentation for risk assessment, and decision-making by environmental managers in this region. 展开更多
关键词 Heavy metals Rice Field Bioconcenration Factor Maga-Pouss ACCUMULATION
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Single crystal growth and characterization of 166-type magnetic kagome metals
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作者 Huangyu Wu Jinjin Liu +5 位作者 Yongkai Li Peng Zhu Liu Yang Fuhong Chen Deng Hu Zhiwei Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期145-150,共6页
Kagome magnets were predicted to be a good platform to investigate correlated topology band structure,Chern quantum phase,and geometrical frustration due to their unique lattice geometry.Here we reported single crysta... Kagome magnets were predicted to be a good platform to investigate correlated topology band structure,Chern quantum phase,and geometrical frustration due to their unique lattice geometry.Here we reported single crystal growth of 166-type kagome magnetic materials,including HfMn_(6)Sn_(6),ZrMn_(6)Sn_(6),GdMn_(6)Sn_(6)and GdV_(6)Sn_(6),by using the flux method with Sn as the flux.Among them,HfMn_(6)Sn_(6)and ZrMn_(6)Sn_(6)single crystals were grown for the first time.X-ray diffraction measurements reveal that all four samples crystallize in HfFe6Ge6-type hexagonal structure with space group P6/mmm.All samples show metallic behavior from temperature dependence of resistivity measurements,and the dominant carrier is hole,except for GdV6Sn6 which is electron dominated.All samples have magnetic order with different transition temperatures,HfMn_(6)Sn_(6),ZrMn_(6)Sn_(6)and GdV_(6)Sn_(6)are antiferromagnetic with TN of 541 K,466 K and 4 K respectively,while GdMn_(6)Sn_(6)is ferrimagnetic with the critical temperature of about 470 K.This study will enrich the research platform of magnetic kagome materials and help explore the novel quantum phenomena in these interesting materials.The dataset of specific crystal structure parameters for HfMn_(6)Sn_(6)are available in Science Data Bank,with the link. 展开更多
关键词 kagome metal single crystal growth crystal structure physical property
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Characterization of Nutrients,Heavy Metals,Petroleum and Their Impact on Phytoplankton in Laizhou Bay:Implications for Environmental Management and Monitoring
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作者 WANG Kai ZHAO Linlin +3 位作者 ZHU Yugui YANG Liqiang WANG Yunfeng HONG Xuguang 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期822-834,共13页
The Laizhou Bay(LB)represents a substantial ecological area that is vulnerable to human activities and confronts diverse environmental challenges.This study provides a comprehensive characterization of nutrients,petro... The Laizhou Bay(LB)represents a substantial ecological area that is vulnerable to human activities and confronts diverse environmental challenges.This study provides a comprehensive characterization of nutrients,petroleum,heavy metals,and phytoplankton community structure across seven distinct areas in LB.The results indicate relatively high concentrations of NO_(2)-N,SiO_(4)-Si,and NO_(3)-N in the Southwest Laizhou Bay(SWLB)and Huanghe River Estuary(HRE).In contrast,the East Laizhou bay(ELB)and the North of Huanghe River Estuary(NHRE)exhibit the highest concentrations of heavy metals(As,Cr and Hg).The areas with high phytoplankton density and community diversity are mainly located in the SWLB.After adjusting for basic environmental factors,phytoplankton density and Margalef richness index D are significantly associated with nutrients(NO_(3)-N,NO_(2)-N,NH_(4)-N,SiO_(4)-Si),and heavy metal(Cr)concentrations.We highlight that,in addition to Xiaoqinghe River,nutrients brought by the Mihe River in the SWLB and heavy metal(Cr)pollution in the ELB resulting from industrial and mining activities along the coast significantly influence phytoplankton growth and community structure.Therefore,it is recommended that more monitoring and management efforts be focused on these regions in the future. 展开更多
关键词 Huanghe River Estuary Laizhou Bay NUTRIENTS heavy metals PHYTOPLANKTON BIODIVERSITY
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Valuable metals recovery from spent ternary lithium-ion battery:A review
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作者 Hao Liao Shengen Zhang +3 位作者 Bo Liu Xuefeng He Jixin Deng Yunji Ding 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第12期2556-2581,共26页
Ternary lithium-ion batteries(LIBs),widely used in new energy vehicles and electronic products,are known for their high en-ergy density,wide operating temperature range,and excellent cycling performance.With the rapid... Ternary lithium-ion batteries(LIBs),widely used in new energy vehicles and electronic products,are known for their high en-ergy density,wide operating temperature range,and excellent cycling performance.With the rapid development of the battery industry,the recycling of spent ternary LIBs has become a hot topic because of their economic value and environmental concerns.To date,a con-siderable amount of literature has reported on the recycling of spent ternary LIBs designed to provide an efficient,economical,and envir-onmentally friendly method for battery recycling.This article examines the latest developments in various technologies for recycling spent ternary LIBs in both research and practical production,including pretreatment,pyrometallurgy,hydrometallurgy,pyro-hydrometallurgy,and direct regeneration.Suggestions for addressing challenges based on the benefits and disadvantages of each method are made.Finally,through a comparison of the feasibility and economic benefits of various technologies,the challenges faced during battery recycling are summarized,and future development directions are proposed. 展开更多
关键词 spent ternary LIBs recycling technologies valuable metals economic analysis
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Assessment of Heavy Metals Contamination of Topsoil and Street Dust around Cement Factory in Southern Jordan
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作者 Omar Ali Al-Khashman Alia Omar Al-Khashman +2 位作者 Navasingh Rajesh Jesudoss Hynes Hani M. Alnawafleh Pitchumani Shenbaga Velu 《Journal of Environmental Protection》 2024年第6期672-696,共25页
Evaluation of assessment of the metal processes governing the metals distribution in soil and dust samples is very significant and protects the health of human and ecological system. Recently, special attention has gi... Evaluation of assessment of the metal processes governing the metals distribution in soil and dust samples is very significant and protects the health of human and ecological system. Recently, special attention has given to the assessment of metals pollution impact on soil and dust within industrial areas. This study aims to assess the metal contamination levels in the topsoil and street dust around the cement factory in Qadissiya area, southern Jordan. The levels of seven metals (namely Fe, Zn, Cu, Pb, Cr, Cd, and Mn) were analyzed using Flame Atomic Absorption Spec-trophotometer (FAAS) to monitor, evaluate, and to compare topsoil and road dust pollution values of metals of the different types of urban area. The physicochemical parameters which believed to affect the mobility of metals in the soil of the study area were determined such as pH, EC, TOM, CaCO3 and CEC. The levels of metal in soil samples are greater on the surface but decrease in the lower part as a result of the basic nature of soil. The mean values of the metals in soil can be arranged in the following order: Zn > Pb > Mn > Fe > Cu > Cr > Cd. The relatively high concentration of metals in the soil sample was attributed to anthropogenic activities such as traffic emissions, cement factory and agricultural activities. Correlation coefficient analysis and the spatial distribution of indices and the results of statistical analysis indicate three groups of metals: Fe and Mn result by natural origin, Zn, Pb, Cu and Zn result by anthropogenic origin (mainly motor vehicle traffic and abrasion of tires) while Cd is mixed origin. The higher content level values of metals of anthropogenic source in soil samples indicate that it is a source of contamination of air in the studied area. . 展开更多
关键词 Cement Dust Heavy metals Contamination Risk Assessment Statistical Analysis JORDAN
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Environmental characteristics of trace metals in seawater from the Ninety East Ridge in the Indian Ocean
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作者 Jingxi LI Di ZHANG +3 位作者 Fenghua JIANG Hong CHEN Wei CAO Chengjun SUN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1119-1129,共11页
The Ninety East Ridge in the Indian Ocean has complex and unique characteristics.The concentrations and distribution characteristics of 10 trace metals(V,Cr,Mn,Fe,Co,Ni,Cu,Cd,Pb,and U)in seawater from the Ninety East ... The Ninety East Ridge in the Indian Ocean has complex and unique characteristics.The concentrations and distribution characteristics of 10 trace metals(V,Cr,Mn,Fe,Co,Ni,Cu,Cd,Pb,and U)in seawater from the Ninety East Ridge in the Indian Ocean were investigated.Results show that the average concentrations of different trace metals in all the collected seawater samples were 1.134μg/L for V,0.158μg/L for Cr,0.489μg/L for Mn,0.427μg/L for Fe,0.011μg/L for Co,0.395μg/L for Ni,0.403μg/L for Cu,0.097μg/L for Cd,0.139μg/L for Pb,and 3.470μg/L for U.Differences in the horizontal and vertical distributions of all measured trace metals were revealed,and the occurrence of high concentrations was nonuniform.In addition,the significant differences in the concentration distribution of different trace metals in seawater on both sides of the Ninety East Ridge present regional segmentation in the area for various trace metals in deep sea water.This study provided basic data for future investigations on the environmental and ecological impact of trace metals in the Indian Ocean and the potential water mass transport mechanism. 展开更多
关键词 trace metal environmental characteristic Ninety East Ridge seawater Indian Ocean
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Evaluation of Agricultural Contamination Level by Heavy Metals and Pesticides in Sediments of Rivers and Water Bodies for Shrimp Fishing in the Lower Ouémé: Case of the Aguigadji, Ahlan and Sele Stations in Benin
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作者 Souradjou Orou Goura Fadéby Modeste Gouissi +3 位作者 Armelle Sabine Yélignan Hounkpatin Wakili Bolatito Yessoufou Tayéwo Sylvain Biaou Nonvignon Martial Fassinou 《Advances in Materials Physics and Chemistry》 CAS 2024年第2期25-46,共22页
This study assessed sediment contamination by heavy metals and pesticide active ingredients linked to chemical inputs used in agricultural activities in the lower Ouémé. Pesticide residues from the organochl... This study assessed sediment contamination by heavy metals and pesticide active ingredients linked to chemical inputs used in agricultural activities in the lower Ouémé. Pesticide residues from the organochlorine, pyrethroid and organophosphorus families were investigated by gas chromatography, and heavy metals (Cd, Pb, As, Ni, Zn, Fe, Mg, Cr and Hg) by atomic absorption spectrophotometry. The metallic pollution indices, the contamination factor (CF) and the ecological risk index were calculated. The results revealed 8 active ingredients in the rainy season and 9 in the dry season. Glyphosate was the active ingredient with the highest concentration at all stations, 9.65 ± 0.84 mg/kg recorded in the dry season at the Aguigadji station. All glyphosate values were above the EQS. DDT, Atrazine and Endosulfan also showed high concentrations in the dry and rainy seasons. Emamectin, Abamectin and Lambda Cyhalothrin also showed high concentrations in the dry season at Aguigadji, Ahlan and Sele. Only glyphosate was recorded at the control station (Toho), but in very low concentrations. Lead showed the highest concentrations at all the stations, 265.96 ± 21.02 mg/Kg in the rainy season and 255.38 ± 79.09 mg/Kg in the dry season, all detected at the Aguigadji station and above the EQS. Zn, Ni, Fe, Cu and Cr were all representative in both the dry and rainy seasons at the contaminated stations. Manganese showed high concentrations in the rainy season. Pb showed very high contamination (FC ≥ 6) at the Aguigadji and Ahlan stations and significant contamination (3 ≤ FC 6) at the Sele station in both the rainy and dry seasons. Ni, Hg and Cd, showed either moderate or significant contamination at the contaminated stations. The risk values showed a considerable ecological Ri (190 ≤ Ri < 380) in the rainy season and a moderate ecological Ri (95 ≤ Ri < 190) in the dry season at these contaminated stations. 展开更多
关键词 PESTICIDES Heavy metals SEDIMENTS Shrimp Fishing Area Lower Ouémé
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Extraction of Valuable Metals from Titanium-bearing Blast Furnace Slag by Acid Leaching
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作者 刘燕 CHEN Xuegui +2 位作者 MAO Shuaidong XIAO Yadong LI Jiacong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期376-385,共10页
To realize the resource utilization of the valuable metals in the titanium-containing blast furnace slag,the process route of “hydrochloric acid leaching-electrolysis-carbonization and carbon dioxide capture-preparat... To realize the resource utilization of the valuable metals in the titanium-containing blast furnace slag,the process route of “hydrochloric acid leaching-electrolysis-carbonization and carbon dioxide capture-preparation of calcium carbonate” was proposed.In this study,the influences of process conditions on the leaching rates of calcium,magnesium,aluminum,and iron and the phases of the leaching residue were investigated for the leaching process.The experimental results show that the HCl solution could selectively leach the elements from the titanium-containing blast furnace slag.The better leaching conditions are the HCl solution concentration of 4 mol/L,the leaching time of 30 min,the ratio of liquid volume to solid gas of 10 mL/g,and the stirring paddle speed of 300 r/min.Under the conditions,the leaching rates of calcium,magnesium,aluminum,and iron can reach 85.87%,73.41%,81.35%,and 59.08%,and the leaching rate of titanium is 10.71%.The iron and the aluminum are removed from the leachate to obtain iron-aluminum water purification agents,and the magnesium is removed from the leachate to obtain magnesium hydroxide.The leaching residue phase is dominated by perovskite,followed by magnesium silicate and tricalcium aluminate,and the titaniumrich material could be obtained from the leaching residue by desiliconization. 展开更多
关键词 titanium-containing blast furnace slag acid leaching valuable metals comprehensive utilization
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Release characteristics and stabilization of heavy metals in antimony tailings in Yunnan Province,China
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作者 LUO Guangfei ZHANG Jin +2 位作者 HAN Zhiwei OUYANG Jidi WU Pan 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3337-3352,共16页
The pollution caused by the mining and smelting of heavy metals is becoming an increasingly severe environmental problem.In this study,the environmental risks of mine tailings were explored using typical antimony tail... The pollution caused by the mining and smelting of heavy metals is becoming an increasingly severe environmental problem.In this study,the environmental risks of mine tailings were explored using typical antimony tailings(the depth of the sample taken from the ground to the deepest position of 120 cm)from the Zuoxiguo mine in Yunnan Province,Southwest China.The tailings were examined to explore the geological background,distribution characteristics,and release characteristics of heavy metals.Additionally,stabilizer treatments for heavy metals were investigated in consideration of waste treatment.The results showed that the contents of Sb and As(8.93×103 and 425 mg/kg,respectively)in the tailings were considerably higher than the local soil background values,suggesting that these metals pose a considerable threat to the surrounding environment.The geological background values of Cr,Cd,Pb,Cu,and Zn were relatively low.The results of static release showed that Sb,As,Cd,and Cr leached from the tailings more easily than Cu,Zn,and Pb under acidic conditions(pH=2.98).Geo-accumulation indices and potential ecological risk indices showed that Sb,As,Cd,and Pb were highly enriched in the tailings,whereas Cu,Cr,and Zn contents were relatively low.The single factor ecological risk index of the mining area showed that Sb and As are high ecological risk factors,whereas Cr,Cu,Zn,Cd,and Pb are not.The results of the orthogonal test results showed that by adding 15.0%(m/m)fly ash and 15.0%(m/m)zeolite powder to the quicklime and curing for 28 d,a significant stabilization effect was observed for Sb,As,and Pb.This study helps determine the priority control components for characteristic heavy metals in antimony tailings,and provides valuable insights regarding the formulation of appropriate mitigation strategies. 展开更多
关键词 Heavy metals Antimony mine Tailing dumps Environmental pollution Release characteristics Stabilization efficiency
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Ab initio nonadiabatic molecular dynamics study on spin–orbit coupling induced spin dynamics in ferromagnetic metals
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作者 朱万松 郑镇法 +1 位作者 郑奇靖 赵瑾 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期156-163,共8页
Understanding the photoexcitation induced spin dynamics in ferromagnetic metals is important for the design of photo-controlled ultrafast spintronic device.In this work,by the ab initio nonadiabatic molecular dynamics... Understanding the photoexcitation induced spin dynamics in ferromagnetic metals is important for the design of photo-controlled ultrafast spintronic device.In this work,by the ab initio nonadiabatic molecular dynamics simulation,we have studied the spin dynamics induced by spin–orbit coupling(SOC)in Co and Fe using both spin-diabatic and spin-adiabatic representations.In Co system,it is found that the Fermi surface(E_(F))is predominantly contributed by the spin-minority states.The SOC induced spin flip will occur for the photo-excited spin-majority electrons as they relax to the E_(F),and the spin-minority electrons tend to relax to the EFwith the same spin through the electron–phonon coupling(EPC).The reduction of spin-majority electrons and the increase of spin-minority electrons lead to demagnetization of Co within100 fs.By contrast,in Fe system,the E_(F) is dominated by the spin-majority states.In this case,the SOC induced spin flip occurs for the photo-excited spin-minority electrons,which leads to a magnetization enhancement.If we move the E_(F) of Fe to higher energy by 0.6eV,the E_(F) will be contributed by the spin-minority states and the demagnetization will be observed again.This work provides a new perspective for understanding the SOC induced spin dynamics mechanism in magnetic metal systems. 展开更多
关键词 nonadiabatic molecular dynamics spin dynamics spin–orbit coupling ferromagnetic metal
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Separation of halogens and recovery of heavy metals from secondary copper smelting dust
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作者 Zhi-lou LIU Zhi-kang CHEN +7 位作者 Fu-ze SUN Zhi-heng ZHANG Kang YAN Shui-ping ZHONG Hui LIU Rui-xiang WANG Jia-yuan LI Zhi-feng XU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2686-2701,共16页
The separation of halogens and recovery of heavy metals from secondary copper smelting(SCS)dust using a sulfating roasting−water leaching process were investigated.The thermodynamic analysis results confirm the feasib... The separation of halogens and recovery of heavy metals from secondary copper smelting(SCS)dust using a sulfating roasting−water leaching process were investigated.The thermodynamic analysis results confirm the feasibility of the phase transformation to metal sulfates and to gaseous HF and HCl.Under the sulfating roasting conditions of the roasting temperature of 250℃ and the sulfuric acid excess coefficient of 1.8,over 74 wt.%of F and 98 wt.%of Cl were volatilized into flue gas.Approximately 98.6 wt.%of Zn and 96.5 wt.%of Cu in the roasting product were dissolved into the leaching solution after the water leaching process,while the leaching efficiencies of Pb and Sn were only 0.12%and 0.22%,respectively.The mechanism studies indicate the pivotal effect of roasting temperature on the sulphation reactions from various metal species to metal sulfates and the salting out reactions from various metal halides to gaseous hydrogen halides. 展开更多
关键词 secondary copper smelting dust sulfating roasting water leaching halogen volatilization heavy metal separation
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Distribution and Transport of Heavy Metals in Rice Plants in the Jiujiang River Basin
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作者 Xinyue XU Chengqi LIN +1 位作者 Yanli ZHOU Huabin HUANG 《Agricultural Biotechnology》 2024年第3期14-17,23,共5页
Inductively coupled plasma mass spectrometry(ICP-MS)was used to analyze the distribution and migration of heavy metals in rice plants in the Jiujiang River Basin,to evaluate the distribution of heavy metals in rice pl... Inductively coupled plasma mass spectrometry(ICP-MS)was used to analyze the distribution and migration of heavy metals in rice plants in the Jiujiang River Basin,to evaluate the distribution of heavy metals in rice plants and to analyze their migration.The results showed that the distribution of different heavy metal elements in various tissues of rice plants varied greatly.The heavy metal migration factor of rice plant stems and leaves was significantly higher than that of rice husk and brown rice.The distribution of heavy metal content in rice in the Jiujiang River can provide a certain theoretical basis and reference value for the safety and quality of rice in the Jiujiang River Basin. 展开更多
关键词 Rice plants Heavy metals TRANSPORT Jiujiang River Basin
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Determination of Total Heavy Metals Content in Local Antidote Manufacturing Resources
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作者 Alexandre Ngama Mwabi Pierre Yoniene Yassa Vestine Ntakarutimana 《Open Journal of Applied Sciences》 2024年第8期2144-2153,共10页
The present work was initiated for searching and evaluating the total heavy metal content in some selected local resources used by traditional healers in locally made antidotes to search for their toxicity. Elekat pub... The present work was initiated for searching and evaluating the total heavy metal content in some selected local resources used by traditional healers in locally made antidotes to search for their toxicity. Elekat public slaughterhouse in the city of Bukavu, the central market of Kadutu and in the Ruzizi plain, precisely in Sange city, have been the purchased centers. The samples of bull and cow horns, oil palm nut shells, cow bones, ginger, black pepper and Mwenga salt were used. The spectrometric method has been used to carry out heavy metal content in each local resource using the atomic absorption spectrometer (VARIAN 1275). The heavy metals found and their average content are as follows: copper (Cu: 124.79 mg/kg), lead (Pb: 76.41 mg/kg), chromium (Cr: 33.9 mg/kg), zinc (Zn: 190.86 mg/kg), Arsenic (As: 107.41 mg/kg) and cadmium (Cd: 0.05 mg/kg). The averages of total heavy metal contents for all samples are below the standard of each one. The determination of the heavy metal contents in these samples allows evaluating human intoxication risk. These results show that antidote technology can be run without any toxicity risk and showed statistically significant differences compared to the controls (p 0.05) for chromium, zinc and cadmium have been recorded. However, most of the heavy metals molecules being thioloprives and then bioccumulatives, antidotes made from them shall not be consumed during a long period. 展开更多
关键词 Heavy metals Local Resources CONTAMINATION ANTIDOTE
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Source of metals related to gold occurrences in Cameroon, Central African Belt
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作者 Kevin Igor Azeuda Ndonfack Jinlin Zhang +2 位作者 Yuling Xie NSamiratou Yaya Emmanuel Archelaus Afanga Basua 《Acta Geochimica》 EI CAS CSCD 2024年第2期308-324,共17页
Suites of granitic and metamorphic rocks form a perfect geological environment in which to investigate the source of metals related to gold deposits.In the East Province of Cameroon,the source of metals-related gold(g... Suites of granitic and metamorphic rocks form a perfect geological environment in which to investigate the source of metals related to gold deposits.In the East Province of Cameroon,the source of metals-related gold(grade~4.6 g/t)that occurs within metamorphic and granitic rocks remains ambiguous.The host rocks were subjected to XRF and ICP-MS whole-rock geochemistry and BSE/EDS mineral analyses to investigate the source(s)of metals related to gold in the Province.Petrographically,chalcopyrite-pyrite and magnetite-ilmenite are the main sulfi des and oxides of granites,respectively.The low-grade metamorphic rocks are sulfi de-rich consisting of arsenopyrite,chalcopyrite,pyrite,and sphalerite,and oxides include magnetite,ilmenite,hematite,and rutile.Cu,Ni,Co,Sb,Sc,and Zn concentrations depleted in high-grade metamorphic rocks and granites compared to low-grade metamorphic rocks.As well,Bi,Cd,Co,Cu,Ni,Sb,V,W,and Zn concentrations decrease with increasing temperatures from low-grade rocks to high-grade rocks and granites.The suite of depleted elements in high-grade rocks and granites is almost identical to those enriched in gold occurrences.We conclude that metals(Bi,Cd,Co,Cu,Ni,Sb,and Zn)related to gold mineralization in the East Province of Cameroon likely originated from metal-rich low-grade metamorphic rocks during prograde metamorphic processes prior to partial melting. 展开更多
关键词 East Province of Cameroon Metamorphic rocks GRANITES Oxide–sulfides metal and gold GEOCHEMISTRY
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Heavy Metals in Agricultural Soils of Constanza, Jarabacoa, San José de Ocoa, Azua, Barahona and San Juan de la Maguana, Dominican Republic, 2022
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作者 Ramón Delanoy Carime Matos-Espinosa Yamilesa Herrera de los Santos 《Journal of Geoscience and Environment Protection》 2024年第1期64-79,共16页
The objective of this study was to establish a baseline for future studies that aim to determine possible contamination from human, agricultural and industrial activities. As well as the determination of the indices o... The objective of this study was to establish a baseline for future studies that aim to determine possible contamination from human, agricultural and industrial activities. As well as the determination of the indices of environmental or geological contamination and enrichment factors of heavy metals Cr, Ni, Cu, Zn, As, Cd, Hg and Pb in agricultural soils of Constanza, Jarabacoa, Rancho Arriba and San José de Ocoa (SJO), municipalities located in the valleys of the Central mountain range of the Dominican Republic. The determination of the concentrations of heavy metals was carried out using the X-ray Fluorescence technique. Just like in Azua, San Juan de la Maguana (SJM) y Barahona in the southwest. Producer municipalities of vegetables, rice, beans, corn, melon, watermelon, tomato, banana, avocado, sugar cane and fodder for cattle. The concentration of 160 mg·kg<sup>-1</sup> Probable Effect Level (PEL) of Cr according to the SQuiRTs table (USEPA-NOAA) for agricultural soils, were exceeded in 50% of the samples in SJM, SJO, Jarabacoa and Constanza;in Barahona and Azua by 20%. The PEL of 42.8 mg·kg-1</sup><sup></sup> of the Ni was higher in more than 50% of the samples from SJM, Azua, Barahona and Jarabacoa;in SJO and Constanza at 35%. In the case of Cu with a PEL of 108 mg·kg-1</sup><sup></sup> in SJO and Constanza, 5% of the samples exceeded its, in the other areas the concentrations were lower. Zn, As and Pb did not manage to exceed their respective PEL. 展开更多
关键词 SOIL Heavy metals Constanza Azua X-Ray Fluorescence
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Transport of Heavy Metals between Soil and Rice in the Jiulong River River Basin
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作者 Jianwei HUANG Chengqi LIN +1 位作者 Yanyun WANG Huabin HUANG 《Agricultural Biotechnology》 2024年第4期87-91,共5页
Diet is one of the main pathways for heavy metals to enter the human body,so studying the content of heavy metals in agricultural products and evaluating them is of great significance.When farmland soil is contaminate... Diet is one of the main pathways for heavy metals to enter the human body,so studying the content of heavy metals in agricultural products and evaluating them is of great significance.When farmland soil is contaminated with heavy metals,the heavy metals accumulated in the soil will be absorbed by the roots of rice plants growing on it,and will migrate and transform between different tissues and organs of rice plants.There is a significant correlation between heavy metal pollution in soil and the content of heavy metals in rice.The migration and enrichment of heavy metals in the agricultural soil rice system is a complex process that is influenced by many factors,such as the physical and chemical properties of the soil,the content and occurrence forms of heavy metals in the soil,and the physiological characteristics of rice plants.In actual field environments,these influencing factors have significant spatial differences and are relatively complex.Therefore,it is necessary to conduct practical analysis of the various influencing factors in actual field environments.Based on actual data analysis,studying the heavy metal content in rice and the characteristics of heavy metal accumulation and migration in rice plants is of great significance for improving the food safety of rice. 展开更多
关键词 Enrichment and migration characteristics Soil Rice System Heavy metals
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