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Dissolution kinetics of a low-grade oxide-sulfide copper ore with high silica content:Laboratory studies and statistical modeling
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作者 Hiva Farhadi Faramarz Doulati Ardejani +5 位作者 Sied Ziaedin Shafaei Tonkaboni Soroush Maghsoudy Roya Kafi Helia Tafakori Christoph Butscher Reza Taherdangkoo 《Acta Geochimica》 2026年第1期111-131,共21页
In this study,copper extraction from low-grade oxide-sulfide ores was investigated using a leaching method combined with response surface methodology(RSM)to optimize operational conditions and assess leaching kinetics... In this study,copper extraction from low-grade oxide-sulfide ores was investigated using a leaching method combined with response surface methodology(RSM)to optimize operational conditions and assess leaching kinetics.Given copper's extensive industrial applications,sustainable recovery from low-grade ores is critical.Five key parameters-acid concentration,leaching time,particle size,temperature,and solids percentage-were identified as major influences on copper recovery.The results revealed that leaching time and solids percentage,along with interactions between temperature-time and temperature-solids percentage,had the most significant effects.Optimal conditions for 80% copper recovery while minimizing iron recovery below 3% included an acid concentration of 1.21 mol L^(-1),a leaching time of 108 min,a particle size of 438μm,a temperature of 45℃,and a solids percentage of 18.2%.Leaching kinetics were analyzed using shrinking core models,with the Dickinson model best describing the process,showing an activation energy of 32.63 kJ mol^(-1),indicative of mixed diffusion and chemical reaction control.The final kinetic model effectively predicted the influence of key parameters.These findings highlight the importance of optimizing process variables and selecting suitable kinetic models to enhance extraction efficiency,reduce costs,and improve sustainability in copper recovery. 展开更多
关键词 Oxide-sulfi de ore Response surface methodology Kinetic analysis Miduk copper mine Shrinking core model copper leaching
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Advances in organoelectrochemical copper-catalyzed reactions
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作者 Pan Zhou Ting Zou +2 位作者 Hong-Jian Song Yu-Xiu Liu Qing-Min Wang 《Chinese Chemical Letters》 2026年第1期25-38,共14页
The combination of electrochemistry and metal catalysts has been a popular research topic in the field of organic synthesis due to the abundance and controllable valence states of transition metals,where electron tran... The combination of electrochemistry and metal catalysts has been a popular research topic in the field of organic synthesis due to the abundance and controllable valence states of transition metals,where electron transfer at the electrode produces catalysts with more valence states.Among these transition metal catalysts,electrochemical conversions catalyzed by inexpensive copper metals have received considerable attention.This article systematically investigated this field and reviewed the electrochemical copper catalytic methods applied in organic synthesis from the different activation modes of substrates,which can be broadly classified into the functionalization of C=C bonds,C-H bond activation,C-C and C-X bond activation,and so on. 展开更多
关键词 ELECTROCHEMISTRY Transition metal catalysis copper catalysis copper electrocatalysis
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Heterogeneous Copper Catalyzed Aerobic Oxidative Cross-Coupling of Tertiary Amines with Alkynes
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作者 Tan Ziyun Yang Xin +6 位作者 Gong Shaofeng Yang Huiling Xie Yongyan Zhang Jingya Feng Zhetai Li Wenyi Xiao Xinsheng 《有机化学》 北大核心 2026年第1期156-166,共11页
The synthesis method of propargylamines has always been the focus of research in organic synthetic methodology.A method of alkynylation of tertiary aliphatic amines with alkynes in the presence of copper doped zeolite... The synthesis method of propargylamines has always been the focus of research in organic synthetic methodology.A method of alkynylation of tertiary aliphatic amines with alkynes in the presence of copper doped zeolite Y as a catalyst and oxygen in the air as an oxidant has been developed.The most important feature of this reaction is that copper molecular siolite is used as catalyst,which avoids the intermolecular self-coupling of alkynes,and thus realizes the high efficiency propargylization of alkyl tertiary amines. 展开更多
关键词 PROPARGYLAMINE copper doped zeolite-Y heterogeneous catalyst cross-coupling reaction
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Preparation of Ultrafine Copper Powders by Ethanol Solvothermal Method and Properties Study
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作者 XU Yite ZHANG Xiang +6 位作者 HE Junpeng WANG Keke CAO Lei ZHU Qian LIU Baixiong LIU Jianfeng XIONG Shixian 《有色金属(中英文)》 北大核心 2026年第1期31-39,共9页
The present work provides a facile and efficient method for producing ultrafine copper powders.Ultrafine copper powders were synthesized through a solvothermal method,utilizing ethanol both as a solvent and a reducing... The present work provides a facile and efficient method for producing ultrafine copper powders.Ultrafine copper powders were synthesized through a solvothermal method,utilizing ethanol both as a solvent and a reducing agent.Specifically,by exploiting the weak reducing property of ethanol,the copper precursor is first converted to copper oxide and then further reduced to cuprous oxide and pure copper.Such a method can effectively control the morphology and particle size of the copper powder,reduce particle aggregation,and enhance oxidation resistance.It is cost-effective and produces fewer toxic by-products.Spherical copper particles with an average particle size of about 180 nm were obtained.The initial oxidation temperature is approximately 150℃,and the resulting copper powders can be stored stably under ambient conditions for at least 5 months,demonstrating excellent oxidation resistance and thermal stability. 展开更多
关键词 alcohol-solvent heat ultrafine copper powder oxidation resistance thermal stability
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Copper-Catalyzed Asymmetric Oxidative Homocoupling Reaction of 3-Hydroxy-2-naphthoates:Design and Optimization of Amino Acid-Based Ligands
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作者 Wang Wen-Long Wen Jia-Xu +4 位作者 Chen Fei Bo Chunbo Li Min Liu Ning Du Zhi-Hong 《有机化学》 北大核心 2026年第1期167-180,共14页
A series of new chiral amide ligands were prepared from natural amino acids and applied to the copper-catalyzed asymmetric oxidative homocoupling reaction of 3-hydroxy-2-naphthoates.By optimizing the reaction conditio... A series of new chiral amide ligands were prepared from natural amino acids and applied to the copper-catalyzed asymmetric oxidative homocoupling reaction of 3-hydroxy-2-naphthoates.By optimizing the reaction conditions,it was found that when using L3(5 mol%)as the ligand,CuCl(5 mol%)as the catalyst,dichloromethane as the solvent,2,2,6,6-tetramethylpiperidine 1-oxyl(TEMPO)/O2 as the oxidant,and under the reaction condition of 40℃,this method exhibited good substrate tolerance.Under these conditions,a series of chiral 1,1'-bi-2-naphthol(BINOL)derivatives were synthesized with yields of 45%~90%and enantioselectivities ranging from 50∶50 to 97∶3. 展开更多
关键词 chiral amide ligand copper catalyst oxidative coupling 3-hydroxy-2-naphthoate 1 1'-bi-2-naphthol(BINOL)
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Innovative cross-intervention:copper ions and metabolic pathways in cancer therapy
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作者 Lili Niu Wei Su +3 位作者 Lixia Ju Jun Xiang Zhou Yang Bing Yao 《Cancer Biology & Medicine》 2026年第1期30-41,共12页
Copper ions are essential for cellular function but can induce cytotoxic effects when dysregulated.This review explores the multifaceted role of copper in cancer metabolism with a focus on the novel concept of cupropt... Copper ions are essential for cellular function but can induce cytotoxic effects when dysregulated.This review explores the multifaceted role of copper in cancer metabolism with a focus on the novel concept of cuproptosis,a regulated form of cell death triggered by copper accumulation.The mechanisms underlying copper homeostasis are detailed,including dietary absorption,systemic distribution,and intracellular utilization.Key transporters,such as copper transporter 1(CTR1)and ATPase copper transporting alpha/b(ATP7A/B),are highlighted.Cancer cells often exhibit elevated copper levels,supporting proliferation and metastasis through pro-tumorigenic pathways.Recent studies have shown that disrupting copper homeostasis can induce cuproptosis,which is characterized by the aggregation of lipoylated mitochondrial proteins and disruption of iron-sulfur cluster biogenesis.Advances in copper-based nanotechnology have enabled targeted delivery of copper to tumors,enhancing therapeutic efficacy through synergistic effects with reactive oxygen species(ROS)generation and immunomodulation.However,the hypoxic tumor microenvironment poses significant challenges by upregulating copper-sequestering proteins and downregulating key cuproptosis mediators.Future directions include integrating multi-omics approaches to identify novel therapeutic targets and developing combination therapies to overcome hypoxia-induced resistance.This review provides a comprehensive overview of copper metabolism in cancer,emphasizing the potential of cuproptosis induction as a powerful strategy for oncologic intervention. 展开更多
关键词 copper homeostasis cuproptosis tumor metabolism nanotherapy hypoxia resistance
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Aging of copper in vineyard topsoil:Use of isotopic labelling to distinguish freshly added copper from aged copper
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作者 Jean-Yves CORNU Pierre EON +1 位作者 Frédéric CANDAUDAP Oleg S.POKROVSKY 《Pedosphere》 2026年第1期368-372,共5页
Dear Editor,The long-term use of copper(Cu)fungicides to prevent downy mildew of vine led to the accumulation of Cu in vineyard topsoils(Komárek et al.,2010;Droz et al.,2021),which may alter the functioning and s... Dear Editor,The long-term use of copper(Cu)fungicides to prevent downy mildew of vine led to the accumulation of Cu in vineyard topsoils(Komárek et al.,2010;Droz et al.,2021),which may alter the functioning and sustainability of vineyard ecosystems(Cornu et al.,2022). 展开更多
关键词 SUSTAINABILITY isotopic labelling downy mildew copper ecosystem functioning vineyard topsoil AGING fungicides
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Effect of hydrogen sulfide on reductive leaching of chalcopyrite by copper
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作者 Xin SUN Rui LIAO +5 位作者 Zu-chao PAN Yi-sheng ZHANG Mao-xin HONG Yan-sheng ZHANG Jun WANG Guan-zhou QIU 《Transactions of Nonferrous Metals Society of China》 2026年第1期287-297,共11页
A series of leaching and electrochemical experiments were conducted to elucidate the critical role of hydrogen sulfide(H_(2)S)in copper-driven reduction of chalcopyrite.Results demonstrate that in the absence of H_(2)... A series of leaching and electrochemical experiments were conducted to elucidate the critical role of hydrogen sulfide(H_(2)S)in copper-driven reduction of chalcopyrite.Results demonstrate that in the absence of H_(2)S,metallic copper converts chalcopyrite into bornite(Cu_(5)FeS_(4)).However,the introduction of H_(2)S promotes the formation of chalcocite(Cu_(2)S)by altering the oxidation pathway of copper.Electrochemical analysis demonstrates that the presence of H₂S significantly reduces the corrosion potential of copper from 0.251 to−0.223 V(vs SHE),reaching the threshold necessary for the formation of Cu_(2)S.Nevertheless,excessive H_(2)S triggers sulfate reduction via the reaction of 8Cu+H_(2)SO_(4)+3H_(2)S=4Cu_(2)S+4H_(2)O(ΔG=−519.429 kJ/mol at 50℃),leading to inefficient copper utilization. 展开更多
关键词 chalcopyrite reduction copper hydrogen sulfide CHALCOCITE
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Emerging role of copper in the pathophysiology of spinal cord injury
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作者 Wenjing Ni Peiling Qiu +4 位作者 Yang Huang Sheng Wang Xiaolei Zhang Yifei Zhou Di Zhang 《Neural Regeneration Research》 2026年第7期2824-2842,共19页
Copper is a trace element that plays an important role in neuronal development,maturation,and function.It also acts as a cofactor for various coppe r-binding proteins or serves as an active component of their structur... Copper is a trace element that plays an important role in neuronal development,maturation,and function.It also acts as a cofactor for various coppe r-binding proteins or serves as an active component of their structure.Acquired copper deficiency has been associated with numerous neurological diseases.Recent research has demonstrated that serum copper concentrations are elevated following spinal cord injury,similar to the elevated copper levels observed after ischemic insult in a rat model of myocardial infa rction.This suggests that spinal cord damage may impair the effective utilization of copper due to local ischemia following spinal cord injury.Studies have shown that copper supplementation may form part of a therapeutic strategy for patients with spinal cord injury.It has been repo rted to promote T-cell diffe rentiation and prolife ration,reduce malondialdehyde levels,decrease myeloperoxidase activity and apoptotic cell numbers,and enhance supe roxide dismutase activity and glutathione levels.Additionally,copper supplementation may stimulate the transc riptional activity of hypoxia-inducible factor and restore angiogenic capacity,thereby increasing capillary density.Furthermore,researchers have found that dihydrolipoamide dehydrogenase,an enzyme involved in inducing cuproptosis,can influence the immune microenvironment of spinal cord injury by promoting copper toxicity.This leads to increased peripheral M2 macrophage polarization and systemic immunosuppression.This led us to hypothesize that copper may influence three major pathological pathways after spinal co rd injury,inflammation,oxidative stress,and cell death,which are critical targets for therapeutic intervention.On the one hand,copper deficiency can cause spinal cord tissue damage;on the other hand,elevated serum copper may induce copper toxicity,contributing to cell death.Therefo re,in this review,we investigate the possible link between spinal cord injury and copper in the perspective of inflammation,oxidative stress,and cell death.Additionally,we review published studies on copper metabolism and explore potential therapeutic strategies by considering va rious sources and mechanisms of copper delive ry. 展开更多
关键词 apoptosis copper cuproptosis ferroptosis inflammation NECROPTOSIS oxidative stress PYROPTOSIS spinal cord injury therapy
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Zhu Bingren:Copper Artist Extraordinaire
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作者 NILS BERGEMANN 《China Today》 2026年第2期73-75,共3页
At 82,master craftsman Zhu Bingren,China’s preeminent copper artist,continues to dynamically evolve his ancient heritage,proving that true preservation lies in innovation and bringing tradition into the contemporary ... At 82,master craftsman Zhu Bingren,China’s preeminent copper artist,continues to dynamically evolve his ancient heritage,proving that true preservation lies in innovation and bringing tradition into the contemporary world.THE copper art should not be confined to display cases,believes artist Zhu Bingren.From living rooms to fashion runways,and from the Great Wall in Beijing to the Louvre in Paris,the Chinese master craftsman brings his metal creations to life in diverse settings. 展开更多
关键词 innovation master craftsman TRADITION copper art contemporary world Zhu Bingren
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Copper Fiber Reinforced Alkali-activated Slag Composite Friction Materials by Hot-pressing Method
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作者 ZHAO Zhe XU Lixin +3 位作者 YANG Jiale SI Jiahui ZHU Song JIANG Changjun 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期381-390,共10页
As the speeds of trains increase,higher demands are placed on brake materials.In order to overcome the thermal degradation phenomenon of brake pads during high-speed braking,we prepared copper fiber reinforced alkali-... As the speeds of trains increase,higher demands are placed on brake materials.In order to overcome the thermal degradation phenomenon of brake pads during high-speed braking,we prepared copper fiber reinforced alkali-activated slag composite(AASC)friction materials by hot-pressing method,using slag as matrix,Na_(2)SiO_(3)·9H_(2)O as alkali excitant,copper fiber as reinforcement,and graphite as friction modifier.The results show that the AASC prepared by hot-pressing method has undergone alkali-activated reaction and has geopolymer amorphous characteristics as the conventional cast molding AASC by XRD analysis.The addition of copper fibers can improve the mechanical strength and toughness of the composites substantially,and the AASC has the highest flexural strength,compressive strength and impact toughness when the volume fraction of copper fibers reaches 25 vol%.Toughening mechanisms such as drawing,bridging and crack deflection of copper fibers in composites were analyzed by SEM morphology.Addition of appropriate amount of graphite to AASC can effectively reduce the wear rate and improve the stability of the material friction coefficient.The coefficient of friction also remains stable in the high-speed friction experiments without thermal degradation.Therefore,copper fiber reinforced AASC friction materials prepared by hot-pressing method has good mechanical and friction properties. 展开更多
关键词 HOT-PRESSING alkali-activated slag copper fiber mechanical properties tribological performance
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Tunable broadband luminescence in lead-free hybrid copper halides
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作者 Yanyan Li Ali Azmy +8 位作者 Shunran Li Huiju Lee Benjamin T.Diroll Mircea Cotlet Lukasz Wojtas Yi Xia Ido Hadar Ioannis Spanopoulos Peijun Guo 《Journal of Energy Chemistry》 2026年第3期362-369,共8页
Metal halides are an important class of optoelectronic materials combining exceptional optical and electronic properties.An inherent advantage of metal halides is their solution synthesis and processability,which rend... Metal halides are an important class of optoelectronic materials combining exceptional optical and electronic properties.An inherent advantage of metal halides is their solution synthesis and processability,which render them as low-cost and environmentally friendly materials for a range of applications from photovoltaics and photodetection to solid-state lighting(SSL).In this study,we synthesized three previously unreported lead-free organic–inorganic hybrid copper halides:(OA)_(4)CuX_(5)(X=Br,I;OA^(+) =C_(8)H_(17)NH_(3)^(+) ,n-octylammonium cation)and(HA)_(2)CuI_(3)(HA^(+) =C_(6)H_(13)NH_(3)^(+) ,n-hexylammonium cation),all of which exhibit broadband emissions arising from self-trapped excitons(STEs).Among these compounds,(OA)_(4)CuI_(5) demonstrates tunable dual-band white-light emission with a high color rendering index value of 91 at room temperature.Temperature-dependent photoluminescence measurements and first-principles calculations reveal distinct behaviors between the two emission states in(OA)_(4)CuI_(5).These findings highlight the potential of copper halide compounds for optoelectronic applications,particularly in the development of environmentally friendly solid-state lighting technologies. 展开更多
关键词 LEAD-FREE Solid-state lighting copper halides Self-trapped excitons
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In situ Raman spectroscopic investigation of copper speciation in hydrothermal fluids at temperatures up to 300℃
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作者 Zhenglong Wang Linbo Shang +6 位作者 I-Ming Chou Chen Chen Yunhe Zhou Jianguo Li Ziqi Jiang Xinwei Gao Ye Wan 《Acta Geochimica》 2026年第1期142-154,共13页
The formation of copper deposits is closely related to hydrothermal processes.Understanding the migration of copper in hydrothermal fluids aids in reconstructing mineralization processes and deciphering deposit genesi... The formation of copper deposits is closely related to hydrothermal processes.Understanding the migration of copper in hydrothermal fluids aids in reconstructing mineralization processes and deciphering deposit genesis.Copper primarily exists as Cu^(+)and Cu^(2+)in hydrothermal solutions,with redox conditions governing their interconversion.In chloride-rich geological fluids,Cu-Cl complexes are considered critical for copper transport.However,the specific types and valence transitions of Cu-Cl complexes under varying hydrothermal conditions remain poorly understood.This study employed in situ Raman spectroscopy to systematically analyze Cu+HCl and CuCl_(2)+K_(2)S_(2)O_(3)/H_(2) systems under saturated vapor pressure at 25-300℃,elucidating the effects of temperature,Cl^(-)concentration,and redox conditions on copper speciation.In the Cu^(+)HCl system,copper dissolved as monovalent Cu-Cl complexes.At high temperatures(>200℃),[CuCl_(2)]^(-)is the dominated species,whereas[CuCl_(3)]^(2-)becomes prevalent at lower temperatures and higher HCl concentrations.For the Cu^(2+)-Cl system,the dominant species transitioned from[Cu(H_(2)O)n]^(2+)(<50℃)to[CuCl_(4)]^(2-)(100℃)and further to[CuCl]^(+)and[CuCl_(2)]^(0) at 300℃.The introduction of reducing agents(K_(2)S_(2)O_(3)/H_(2))facilitated Cu^(2+)→Cu^(+)reduction,thereby stabilizing Cu^(+)-Cl complexes and inducing partial copper precipitation.The behavior of copper in chloriderich hydrothermal fluids observed in this study indicates that high-temperature oxidizing fluids facilitate Cu mobilization,while cooling and redox changes promote deposition and ore minerals formation. 展开更多
关键词 Raman spectroscopy In situ analysis Hydrothermal fluids copper Transport mechanism
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Effect of fluoride roasting on copper species transformation on chrysocolla surfaces and its role in enhanced sulfidation flotation
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作者 Yingqiang Ma Xin Huang +5 位作者 Yafeng Fu Zhenguo Song Sen Luo Shuanglin Zheng Feng Rao Wanzhong Yin 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期165-176,共12页
It is difficult to recover chrysocolla from sulfidation flotation which is closely related to the mineral surface composition.In this study,the effects of fluoride roasting on the surface composition of chrysocolla we... It is difficult to recover chrysocolla from sulfidation flotation which is closely related to the mineral surface composition.In this study,the effects of fluoride roasting on the surface composition of chrysocolla were investigated,its impact on sulfidation flotation was explored,and the mechanisms involved in both fluoride roasting and sulfidation flotation were discussed.With CaF_(2)as the roasting reagent,Na_(2)S·9H_(2)O as the sulfidation reagent,and sodium butyl xanthate(NaBX)as the collector,the results of the flotation experiments showed that fluoride roasting improved the floatability of chrysocolla,and the recovery rate increased from 16.87%to 82.74%.X-ray diffraction analysis revealed that after fluoride roasting,approximately all the Cu on the chrysocolla surface was exposed in the form of CuO,which could provide a basis for subsequent sulfidation flotation.The microscopy and elemental analyses revealed that large quantities of"pagoda-like"grains were observed on the sulfidation surface of the fluoride-roasted chrysocolla,indicating high crystallinity particles of copper sulfide.This suggests that the effect of sulfide formation on the chrysocolla surface was more pronounced.X-ray photoelectron spectroscopy revealed that fluoride roasting increased the relative contents of sulfur and copper on the surface and that both the Cu~+and polysulfide fractions on the surface of the minerals increased.This enhances the effect of sulfidation,which is conducive to flotation recovery.Therefore,fluoride roasting improved the effect of copper species transformation and sulfidation on the surface of chysocolla,promoted the adsorption of collectors,and improved the recovery of chrysocolla from sulfidation flotation. 展开更多
关键词 sulfidation flotation CHRYSOCOLLA fluoride roasting copper species transformation enhanced sulfidation
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Flame-retardant rigid polyurethane foam composites based on copper tailings and melamine polyphosphate:a novel strategy for copper tailings utilization
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作者 Cun-Long Fu Xu-Hao Zhen +5 位作者 Rui Wang Xiao-Yan Du Hong-Ming Long Xiu-Yu Liu Gang Tang Kang Dai 《Journal of Iron and Steel Research International》 2026年第2期332-343,共12页
In view of the problems such as the low utilization efficiency of copper tailings solid waste,which leads to severe environmental pollution,and the easy combustibility of rigid polyurethane foam(RPUF)along with the ge... In view of the problems such as the low utilization efficiency of copper tailings solid waste,which leads to severe environmental pollution,and the easy combustibility of rigid polyurethane foam(RPUF)along with the generation of a large amount of toxic smoke during combustion,copper tailings were combined with melamine polyphosphate to prepare RPUF composites.The flame-retardant properties were investigated,and the structure–property relationship was clarified.It was found that when 16.7 g of copper tailings and 33.3 g of melamine polyphosphate were added,the limiting oxygen index increased to 23.0 vol.%,and the vertical burning rating(UL-94)reached V-0.The peak heat release rate was reduced by 27.79%compared to pure RPUF,and the fire growth index decreased to 4.54 kW/(m^(2)s),representing a 75.42%reduction.The char residue rate at 750℃ increased from 17.6% to 28.51%.Moreover,the addition of copper tailings and melamine polyphosphate effectively promoted the charring of RPUF,forming a dense char layer with good fire resistance performance. 展开更多
关键词 copper tailing Rigid polyurethane foam Flame retardancy Thermal stability Waste utilization
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Comparison of Electrically Excited Synchronous Machines Using Copper and Aluminum Windings in Stator and Rotor
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作者 Tianzheng Xiao Zi Qiang Zhu Ziad Azar 《CES Transactions on Electrical Machines and Systems》 2026年第1期16-27,共12页
In this paper,electrically excited synchronous machines(EESMs)using copper(Cu)and aluminum(Al)windings are compared for the feasibility of replacing Cu windings with Al windings in electric vehicle(EV)applications sin... In this paper,electrically excited synchronous machines(EESMs)using copper(Cu)and aluminum(Al)windings are compared for the feasibility of replacing Cu windings with Al windings in electric vehicle(EV)applications since Al windings have lower mass density and cost per weight,but higher resistivity and lower thermal conductivity than Cu windings.The EESMs with four winding configurations are optimized with an electromagnetic-thermal co-optimization method.The optimized EESM with only Cu windings is considered as the baseline in this study.Results show that the EESM with stator-Cu/rotor-Al windings has the least torque reduction(12.1%)compared to the baseline among the three EESMs with Al windings and the highest torque mass density among all EESMs.Meanwhile,although the new European driving cycle efficiency of the stator-Cu/rotor-Al EESM is 1.8%lower than that of the baseline,the torque per cost is 71%higher,and the maximum rotor mechanical stress is 8%lower.Therefore,the EESMs with stator-Cu/rotor-Al windings are prospective substitutions of those with only Cu windings for EV applications considering the trade-off between performance and cost. 展开更多
关键词 Aluminum winding copper winding Cost efficiency Electrically excited synchronous machines Torque density Winding temperature
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Anisotropy of Phase Transformation in Aluminum and Copper under Shock Compression:Atomistic Simulations and Neural Network Model
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作者 Evgenii V.Fomin Ilya A.Bryukhanov +1 位作者 Natalya A.Grachyova Alexander E.Mayer 《Computers, Materials & Continua》 2026年第4期548-577,共30页
It is well known that aluminum and copper exhibit structural phase transformations in quasi-static and dynamic measurements,including shock wave loading.However,the dependence of phase transformations in a wide range ... It is well known that aluminum and copper exhibit structural phase transformations in quasi-static and dynamic measurements,including shock wave loading.However,the dependence of phase transformations in a wide range of crystallographic directions of shock loading has not been revealed.In this work,we calculated the shock Hugoniot for aluminum and copper in different crystallographic directions([100],[110],[111],[112],[102],[114],[123],[134],[221]and[401])of shock compression using molecular dynamics(MD)simulations.The results showed a high pressure(>160 GPa for Cu and>40 GPa for Al)of the FCC-to-BCC transition.In copper,different characteristics of the phase transition are observed depending on the loading direction with the[100]compression direction being the weakest.The FCC-to-BCC transition for copper is in the range of 150–220 GPa,which is consistent with the existing experimental data.Due to the high transition pressure,the BCC phase transition in copper competes with melting.In aluminum,the FCC-to-BCC transition is observed for all studied directions at pressures between 40 and 50 GPa far beyond the melting.In all considered cases we observe the coexistence of HCP and BCC phases during the FCC-to-BCC transition,which is consistent with the experimental data and atomistic calculations;this HCP phase forms in the course of accompanying plastic deformation with dislocation activity in the parent FCC phase.The plasticity incipience is also anisotropic in bothmetals,which is due to the difference in the projections of stress on the slip plane for different orientations of the FCC crystal.MD modeling results demonstrate a strong dependence of the FCC-to-BCC transition on the crystallographic direction,in which the material is loaded in the copper crystals.However,MD simulations data can only be obtained for specific points in the stereographic direction space;therefore,for more comprehensive understanding of the phase transition process,a feed-forward neural network was trained using MD modeling data.The trained machine learning model allowed us to construct continuous stereographic maps of phase transitions as a function of stress in the shock-compressed state of metal.Due to appearance and growth of multiple centers of new phase,the FCC-to-BCC transition leads to formation of a polycrystalline structure from the parent single crystal. 展开更多
关键词 Molecular dynamics(MD) ALUMINUM copper shock wave polymorphic phase transformation polycrystalline structure neural network model
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Noncovalent Interaction-Mediated Space Charge Transition Facilitated Isolated Copper(I)-Iodide Clusters:Enabling High-Resolution X-Ray Imaging and Dynamic Encryption
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作者 Zhao-Xing Gao Wen-Fei Wang +3 位作者 Mian-He Xu Shuai-Hua Wang Fa-Kun Zheng Guo-Cong Guo 《Aggregate》 2026年第2期241-249,共9页
The exploration of solvent-driven reversible structural transformation in clusters is crucial for advanced stimulus-responsive optical applications and understanding of structure-property relationships.Herein,we repor... The exploration of solvent-driven reversible structural transformation in clusters is crucial for advanced stimulus-responsive optical applications and understanding of structure-property relationships.Herein,we report a solvent-driven reversible trans-formation between two copper(I)clusters:[Cu(totp)(CH_(3)CN)_(3)][Cu_(2)I_(3)(totp)(DPPPy)]·CH_(3)CN 1 and Cu_(4)I_(4)(DPPPy)_(2)·0.5CH_(2)Cl_(2)2(totp=tri-o-tolylphosphine,DPPPy=2-[diphenylphosphino]pyridine).X-ray radioluminescence and encryption applications were studied based on structure-dependent photophysical properties difference.The noncovalent interaction-mediated space charge transition between isolated ion units of 1 enables more efficient thermally activated delayed fluorescence by reverse intersystem crossing,accounting for structure-dependent luminescence.Notably,compared to 2,1 exhibits a higher scintillation light yield of 14832 photons MeV^(-1),exceeding that of the commercial scintillator Bi_(4)Ge_(3)O_(12)(8000 photons MeV^(-1)),and a low X-ray detection limit of 22.49 nGy s^(-1),far below the typical diagnostic dose(5.5μGy s^(-1)).Furthermore,scintillating film fabricated by 1 achieves X-ray imaging with a high spatial resolution of 16 lp/mm.The reversible structural interconversion enables solvent-responsive luminescent switches,and thus,the dynamic encryption system capable of multistage decryption was developed.This work not only offers new insight into solvent-regulated clusters transformations but also provides a promising strategy for developing high-performance copper(I)clusters-based scintillators and stimulus-responsive optical devices. 展开更多
关键词 copper(I)-iodide clusters information encryption solvent-driven structural transformation X-ray imaging
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An Analysis of Contemporary Copper Recycling in China 被引量:9
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作者 岳强 陆钟武 《过程工程学报》 CAS CSCD 北大核心 2006年第4期683-690,共8页
Copper consumption increased very quickly in China in recent years,which could not be met by inland copper industry.In order to achieve a sustainable development of copper industry,an analysis of copper recycling in C... Copper consumption increased very quickly in China in recent years,which could not be met by inland copper industry.In order to achieve a sustainable development of copper industry,an analysis of copper recycling in China was necessary.For the life cycle of copper products a copper-flow diagram with time factor was worked out and the contemporary copper recycling in China was analyzed,from which the following data were obtained.The average life cycle of copper products was 30 years.From 1998 to 2002,the use ratio of copper scraps in copper production,the use ratio of copper scraps in copper manufacture,the materials self-support ratio in copper production,and the materials self-support ratio in copper manufacture were 26.50%,15.49%,48.05% and 59.41%,respectively.The materials self-support ratios in copper production and manufacture declined year by year in recent years on the whole,and the latter dropped more quickly.The average index of copper ore and copper scrap from 1998 to 2002 were 0.8475 t/t and 0.0736 t/t,respectively;and copper resource efficiency was 1.1855 t/t.Some efforts should be paid to reduce copper ores consumption and promote copper scraps regeneration.Copper scraps were mostly imported from foreign countries because of shortage in recent years in China.Here the reasons related to copper scraps deficiency were also demonstrated.But we can forecast:when copper production was in a slow rise or in a steady state in China,the deficiency of copper scraps may be mitigated;when copper production was in a steady state for a very long time,copper scraps may become relatively abundant.According to the status of copper industry in China,the raw materials of copper production and manufacture have to depend on oversea markets heavily in recent years,and at the same time,the copper scraps using proportion and efficiency in copper industry should be improved. 展开更多
关键词 copper scrap copper recycling copper-flow diagram of the life cycle of copper products self-support ratio copper ore index copper scrap index copper resource efficiency
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Distribution and Fate of Arsenic in Copper Mining,Beneficiation and Smelting in China
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作者 HAN Wei WANG Yujing NIE Jinglei 《有色金属(中英文)》 北大核心 2025年第10期1844-1853,共10页
Copper smelting is the main source of arsenic pollution in the environment,and China is the largest country for copper smelting.Taking 2022 as an example,this study analyzes the distribution and fate of arsenic across... Copper smelting is the main source of arsenic pollution in the environment,and China is the largest country for copper smelting.Taking 2022 as an example,this study analyzes the distribution and fate of arsenic across the copper mining,beneficiation,and smelting processes using a life-cycle approach,providing important insights for arsenic pollution prevention and the resource utilization of arsenic-bearing solid waste.The results show that the amount of As in waste rock,tailing and concentrate are 53483 t,86632 t,76162 t,respectively.After smelting treatment,the amount of arsenic in different types of solid waste,wastewater,waste gas and products are 76128 t,1 t,31 t and 2 t,respectively,and the proportion in arsenic sulfide slag is the highest(55%).The amount of emission to the environment is 32 t,accounting for only 0.04%of total amount.In the future,key considerations are to improve the resource utilization rate of arsenic-containing solid waste(tailing,smelting slag),especially arsenic sulfide slag,and to digest its environmental risk. 展开更多
关键词 arsenic contamination copper mining copper beneficiation copper smelting material flow
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