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Evaluation of flow behavior in copper electro-refining cell with different inlet arrangements 被引量:4
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作者 Ping ZHOU Hai-bo MA +2 位作者 Zi-wei XIE Hong-jie YAN Chenn Q. ZHOU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第10期2282-2290,共9页
The arrangement of electrolyte inlet in the copper electro-refining(ER)cell has a great influence on the local flow field,which affects the distribution of electrical current density in consequence.In order to underst... The arrangement of electrolyte inlet in the copper electro-refining(ER)cell has a great influence on the local flow field,which affects the distribution of electrical current density in consequence.In order to understand the complicated phenomena ofelectrolyte flow behavior in vertical counter electrodes in full-scale copper ER cell,the three-dimensional computational fluiddynamics(CFD)models with four different arrangements of electrolyte inlets,i.e.,single inlet(SI),central bottom inlets(CBI),topside interlaced inlets(TII),and bottom side interlaced inlets(BII),were established to simulate the flow behavior.Simulation resultshave revealed that the parallel injection devices help to improve the electrolyte velocity between electrodes,and while the relativerange of electrolyte velocity in CBI exceeds that of TII and BII,which is more than4times,indicating its severer unequal flowdistribution.Meanwhile,the average velocity of electrolyte in BII is4times larger than that of SI due to its higher turbulenceintensity.Generally,one of the efficient ways to supply fresh copper solution rapidly and uniformly into the inter-electrode space is toadapt the arrangement of BII.By utilizing such an arrangement,the electro-refining under high electrical current density is possible,and the productivity can be increased in sequence. 展开更多
关键词 copper electro-refining electrolyte inlet arrangement flow uniformity computational fluid dynamics
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Modeling Operational Parameters of a Reactive Electro-Dialysis Cell for Electro-Refining Anodic Scrap Copper
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作者 Gerardo Cifuentes José Hernández +1 位作者 Jorge Manríquez Nicolas Guajardo 《American Journal of Analytical Chemistry》 2014年第15期1011-1019,共9页
This work will create an electro-dialysis cell model that has the purpose of refining anodic scrap copper—an element that currently must be returned to the copper conversion process. The cell modeling is based on Ohm... This work will create an electro-dialysis cell model that has the purpose of refining anodic scrap copper—an element that currently must be returned to the copper conversion process. The cell modeling is based on Ohm’s Law, while the resulting copper deposit morphology is studied through the thickness of the layer deposited on the surface and the electric current lines traced from the anode to the cathode. The use of the model demonstrated that it is possible to effectively predict the specific energy consumption required for the refinement of the anodic scrap copper, and the morphology of the cathode obtained, with a margin of error of 9%. 展开更多
关键词 electro-refining MODELING copper SCRAP REACTIVE Electro-Dialysis Specific Consumption
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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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Copper homeostasis and neurodegenerative diseases 被引量:2
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作者 Yuanyuan Wang Daidi Li +2 位作者 Kaifei Xu Guoqing Wang Feng Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第11期3124-3143,共20页
Copper,one of the most prolific transition metals in the body,is required for normal brain physiological activity and allows various functions to work normally through its range of concentrations.Copper homeostasis is... Copper,one of the most prolific transition metals in the body,is required for normal brain physiological activity and allows various functions to work normally through its range of concentrations.Copper homeostasis is meticulously maintained through a complex network of copper-dependent proteins,including copper transporters(CTR1 and CTR2),the two copper ion transporters the Cu-transporting ATPase 1(ATP7A)and Cu-transporting beta(ATP7B),and the three copper chaperones ATOX1,CCS,and COX17.Disruptions in copper homeostasis can lead to either the deficiency or accumulation of copper in brain tissue.Emerging evidence suggests that abnormal copper metabolism or copper binding to various proteins,including ceruloplasmin and metallothionein,is involved in the pathogenesis of neurodegenerative disorders.However,the exact mechanisms underlying these processes are not known.Copper is a potent oxidant that increases reactive oxygen species production and promotes oxidative stress.Elevated reactive oxygen species levels may further compromise mitochondrial integrity and cause mitochondrial dysfunction.Reactive oxygen species serve as key signaling molecules in copper-induced neuroinflammation,with elevated levels activating several critical inflammatory pathways.Additionally,copper can bind aberrantly to several neuronal proteins,including alphasynuclein,tau,superoxide dismutase 1,and huntingtin,thereby inducing neurotoxicity and ultimately cell death.This study focuses on the latest literature evaluating the role of copper in neurodegenerative diseases,with a particular focus on copper-containing metalloenzymes and copper-binding proteins in the regulation of copper homeostasis and their involvement in neurodegenerative disease pathogenesis.By synthesizing the current findings on the functions of copper in oxidative stress,neuroinflammation,mitochondrial dysfunction,and protein misfolding,we aim to elucidate the mechanisms by which copper contributes to a wide range of hereditary and neuronal disorders,such as Wilson's disease,Menkes'disease,Alzheimer's disease,Parkinson's disease,amyotrophic lateral sclerosis,Huntington's disease,and multiple sclerosis.Potential clinically significant therapeutic targets,including superoxide dismutase 1,D-penicillamine,and 5,7-dichloro-2-[(dimethylamino)methyl]-8-hydroxyquinoline,along with their associated therapeutic agents,are further discussed.Ultimately,we collate evidence that copper homeostasis may function in the underlying etiology of several neurodegenerative diseases and offer novel insights into the potential prevention and treatment of these diseases based on copper homeostasis. 展开更多
关键词 Alzheimer's disease amyotrophic lateral sclerosis disease copper homeostasis copper toxicity Huntington's disease Menkes'disease multiple sclerosis neurodegenerative disease Parkinson's disease Wilson's disease
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Role of copper in central nervous system physiology and pathology 被引量:3
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作者 Martina Locatelli Cinthia Farina 《Neural Regeneration Research》 SCIE CAS 2025年第4期1058-1068,共11页
Copper is a transition metal and an essential element for the organism,as alterations in its homeostasis leading to metal accumulation or deficiency have pathological effects in several organs,including the central ne... Copper is a transition metal and an essential element for the organism,as alterations in its homeostasis leading to metal accumulation or deficiency have pathological effects in several organs,including the central nervous system.Central copper dysregulations have been evidenced in two genetic disorders characterized by mutations in the copper-ATPases ATP7A and ATP7B,Menkes disease and Wilson’s disease,respectively,and also in multifactorial neurological disorders such as Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis,and multiple sclerosis.This review summarizes current knowledge about the role of copper in central nervous system physiology and pathology,reports about unbalances in copper levels and/or distribution under disease,describes relevant animal models for human disorders where copper metabolism genes are dysregulated,and discusses relevant therapeutic approaches modulating copper availability.Overall,alterations in copper metabolism may contribute to the etiology of central nervous system disorders and represent relevant therapeutic targets to restore tissue homeostasis. 展开更多
关键词 ASTROCYTES central nervous system copper CUPRIZONE multiple sclerosis MYELIN neurodegenerative disorders
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Role of copper chelating agents: between old applications and new perspectives in neuroscience 被引量:2
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作者 Rosalba Leuci Leonardo Brunetti +4 位作者 Vincenzo Tufarelli Marco Cerini Marco Paparella Nikola Puvača Luca Piemontese 《Neural Regeneration Research》 SCIE CAS 2025年第3期751-762,共12页
The role of copper element has been an increasingly relevant topic in recent years in the fields of human and animal health, for both the study of new drugs and innovative food and feed supplements. This metal plays a... The role of copper element has been an increasingly relevant topic in recent years in the fields of human and animal health, for both the study of new drugs and innovative food and feed supplements. This metal plays an important role in the central nervous system, where it is associated with glutamatergic signaling, and it is widely involved in inflammatory processes. Thus, diseases involving copper(Ⅱ) dyshomeostasis often have neurological symptoms, as exemplified by Alzheimer's and other diseases(such as Parkinson's and Wilson's diseases). Moreover, imbalanced copper ion concentrations have also been associated with diabetes and certain types of cancer, including glioma. In this paper, we propose a comprehensive overview of recent results that show the importance of these metal ions in several pathologies, mainly Alzheimer's disease, through the lens of the development and use of copper chelators as research compounds and potential therapeutics if included in multi-target hybrid drugs. Seeing how copper homeostasis is important for the well-being of animals as well as humans, we shortly describe the state of the art regarding the effects of copper and its chelators in agriculture, livestock rearing, and aquaculture, as ingredients for the formulation of feed supplements as well as to prevent the effects of pollution on animal productions. 展开更多
关键词 agriculture Alzheimer's disease CHELATORS copper feed supplements MULTI-TARGET
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Performance of stabilized copper mine tailings with freeze-thaw and wet-dry seasonal cycles 被引量:2
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作者 Uddav Ghimire Tejo V.Bheemasetti Hee-Jeong Kim 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1418-1428,共11页
Approximately 3.44 billion tons of copper mine tailings(MT)were produced globally in 2018 with an increase of 45%from 2010.Significant efforts are being made to manage these tailings through storage facilities,recycli... Approximately 3.44 billion tons of copper mine tailings(MT)were produced globally in 2018 with an increase of 45%from 2010.Significant efforts are being made to manage these tailings through storage facilities,recycling,and reuse in different industries.Currently,a large portion of tailings are managed through the tailing storage facilities(TSF)where these tailings undergo hydro-thermal-mechanical stresses with seasonal cycles which are not comprehensively understood.This study presents an investigative study to evaluate the performance of control and cement-stabilized copper MT under the influence of seasonal cycles,freeze-thaw(F-T)and wet-dry(W-D)conditions,representing the seasonal variability in the cold and arid regions.The control and cement-stabilized MT samples were subjected to a maximum of 12 F-T and 12 W-D cycles and corresponding micro-and-macro behavior was investigated through scanning electron microscope(SEM),volumetric strain(εvT,wet density(r),moisture content loss,and unconfined compressive strength(UCS)tests.The results indicated the vulnerability of Copper MT to 67%and 75%strength loss reaching residual states with 12 F-T and 8 W-D cycles,respectively.Whereas the stabilized MT retained 39%-55%and 16%-34%strength with F-T and W-D cycles,demonstrating increased durability.This research highlights the impact of seasonal cycles and corresponding strength-deformation characteristics of control and stabilized Copper MT in cold and arid regions. 展开更多
关键词 copper mine tailings(MT) Stabilization Seasonal cycles Cold and arid region
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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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Advances in electrolytic copper foils:fabrication,microstructure,and mechanical properties 被引量:1
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作者 Long-Long Lu Hai-Tao Liu +8 位作者 Zhao-Dong Wang Qiong-Qiong Lu Yan-Jun Zhou Fei Zhou Yan-Min Zhang Wei-Wei Lu Bin Yang Qian-Qian Zhu Ke-Xing Song 《Rare Metals》 2025年第2期757-792,共36页
Electrolytic copper foil has gained significant attention as an essential component in lithium-ion batteries(LIBs),printed circuit boards(PCBs),and chip packaging substrates(CPSs)applications.With the advancement of L... Electrolytic copper foil has gained significant attention as an essential component in lithium-ion batteries(LIBs),printed circuit boards(PCBs),and chip packaging substrates(CPSs)applications.With the advancement of LIBs towards higher energy densities and the increasing density of electronic components on circuits,copper foil is required to have demanding properties,such as extremely thin thickness and extremely high tensile strength.This comprehensive review firstly summarizes recent progress on the fabrication of electrolytic copper foil,and the effects of process parameters,cathode substrate,and additives on the electrodeposition behavior,microstructure,and properties of copper foil are discussed in detail.Then the regulation strategies of mechanical properties of electrolytic copper foil are also summarized,including the formation of nanotwins and texture.Furthermore,the recent advances in novel electrolytic copper foils,such as composite foils and extra-thin copper foils,are also overviewed.Lastly,the remaining challenges and perspectives on the further development of electrolytic copper foils are presented. 展开更多
关键词 Electrolytic copper foil Fabrication processes ELECTRODEPOSITION MICROSTRUCTURE Mechanical properties
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Recovery of copper and cobalt from waste rock in Democratic Republic of Congo by gravity separation combined with flotation 被引量:1
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作者 Qing-qing WANG Lei SUN +5 位作者 Yang CAO Xin WANG Yi QIAO Mei-tao XIANG Guo-bin LIU Wei SUN 《Transactions of Nonferrous Metals Society of China》 2025年第2期602-612,共11页
Copper and cobalt were recovered from SICOMINES mining waste rock in the Democratic Republic of Congo.The process mineralogy of the samples was analyzed using scanning electron microscopy and energy dispersive spectro... Copper and cobalt were recovered from SICOMINES mining waste rock in the Democratic Republic of Congo.The process mineralogy of the samples was analyzed using scanning electron microscopy and energy dispersive spectroscopy.The results showed that copper minerals exhibited various forms and uneven particle sizes,while cobalt existed in the form of highly dispersed asbolane,and large amounts of easily slimed gangue minerals were filled in the samples,making it difficult to separate copper and cobalt minerals.The particle size range plays a decisive role in selecting the separation method for the copper−cobalt ore.Gravity separation was suitable for particles ranging from 43 to 246μm,while flotation was more effective for particles below 43μm.After ore grinding and particle size classification,applying a combined gravity separation(shaking table)−flotation method yielded concentrated minerals with a copper recovery of 72.83%and a cobalt recovery of 31.13%. 展开更多
关键词 copper−cobalt waste ore process mineralogy pre-classification FLOTATION gravity separation
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Stable Cu(Ⅰ)single copper atoms supported on porous carbon nitride nanosheets for efficient photocatalytic degradation of antibiotics 被引量:1
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作者 Xiao-Ye Xu Xiu-Hang Liu +7 位作者 Hui-Hui Gan Ding-Nan Lu Xiao-Meng Jiang Meng-Fei Yu Shuo Pan Jia-Yue Luo Hong-Li Sun Xue-Hua Zhang 《Rare Metals》 2025年第3期1756-1766,共11页
Exploration of stable metal single-site supported porous graphitic carbon nitride(PCN)nanostructures and the development of maximum atom utilization for enhanced photocatalytic oxidation of antibiotics remains a chall... Exploration of stable metal single-site supported porous graphitic carbon nitride(PCN)nanostructures and the development of maximum atom utilization for enhanced photocatalytic oxidation of antibiotics remains a challenge in current research.This work proposed a one-step thermal copolymerization to obtain Cu(Ⅰ)doping porous carbon nitride(CUCN)through a spontaneously reducing atmosphere by urea in a covered crucible.The obtained CUCN had crumpled ultrathin nanosheets and mesoporous structures,which possessed higher specific surface areas than PCN.From X-ray absorption near edge structure(XANES)and Fourier transform extended X-ray absorption fine structure(FT-EXAFS)spectra analysis,the Cu doping existed in the oxidation state of Cu(Ⅰ)as single atoms anchored on the 2D layers of CN through two N neighbors,thereby facilitating efficient pathways for the transfer of photoexcited charge carriers.Furthermore,the photoluminescence(PL)spectra,electrochemical impedance spectra(EIS)and transient photocurrent response test proved the improved separation and transfer of photoexcited charge carriers for Cu(Ⅰ)introduction.Consequently,the photocatalytic activity of CUCN was much better than that of PCN for antibiotics norfloxacin(NOR),with 4.7-fold higher degradation reaction rate constants.From species-trapping experiments and density function theory(DFT)calculations,the Cu single atoms in Cu-N_(2)served as catalytic sites that could accelerate charge transfer and facilitate the adsorption of molecular oxygen to produce active species.The stable Cu(Ⅰ)embedded in the layer structure led to the excellent recycling test and remained stable after four runs of degradation and even thermal regenerated treatment.The degradation paths of NOR by CUCN under visible light were also demonstrated.Our work sheds light on a sustainable and practical approach for achieving stable metal single-atom doping and enhancing photocatalytic degradation of aqueous pollutants. 展开更多
关键词 Graphitic carbon nitride Antibiotic degradation Cu single copper atom Active species Degradation pathways
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Dual-ligand-modified copper nanoclusters:Synthesis and application in ornidazole detection
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作者 TIAN Rui LI Duo +4 位作者 REN Yuan CHAI Jiamin SUN Xuehua LI Haoyu ZHANG Yuecheng 《无机化学学报》 北大核心 2025年第6期1245-1255,共11页
Bovine serum albumin(BSA)and glycine(Gly)dual-ligand-modified copper nanoclusters(BSA-Gly CuNCs)with high fluorescence intensity were synthesized by a one-pot strategy.Based on the competitive fluorescence quenching a... Bovine serum albumin(BSA)and glycine(Gly)dual-ligand-modified copper nanoclusters(BSA-Gly CuNCs)with high fluorescence intensity were synthesized by a one-pot strategy.Based on the competitive fluorescence quenching and dynamic quenching effects of ornidazole(ONZ)on BSA-Gly CuNCs,a simple and sensitive detection method for ONZ was successfully developed.The experimental results demonstrate that the addition of the small molecule Gly can more effectively protect CuNCs,and thus enhance its fluorescence intensity and stability.The proposed assay allowed for the detection of ONZ in a linear range of 0.28 to 52.60μmol·L^(-1)and a detection limit of 0.069μmol·L^(-1).Compared with the single-ligand-modified CuNCs,dual-ligand-modified BSA-Gly CuNCs had higher fluorescence intensity,stability,and sensing ability and were successfully applied to evaluate ONZ in actual ONZ tablets. 展开更多
关键词 copper nanocluster ORNIDAZOLE dual-ligand-modified fluorescence detection
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Chitosan/silica-coated copper nanoclusters:Synthesis and application in cefixime detection
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作者 TIAN Rui CHAI Jiamin +4 位作者 CHEN Junyu REN Yuan SUN Xuehua LI Haoyu ZHANG Yuecheng 《无机化学学报》 北大核心 2025年第9期1903-1915,共13页
Herein,copper nanoclusters(Cu NCs)were synthesized in aqueous solution through a chemical reduction method using polyethyleneimine as reducing agent and protective ligand,with Cu(NO_(3))_(2)as copper source.Subse-quen... Herein,copper nanoclusters(Cu NCs)were synthesized in aqueous solution through a chemical reduction method using polyethyleneimine as reducing agent and protective ligand,with Cu(NO_(3))_(2)as copper source.Subse-quently,composite fluorescent nanoparticles,chitosan-functionalized silica nanoparticles(CSNPs)-coated Cu NCs(Cu NCs/CSNPs),were synthesized via a reverse microemulsion method.Compared with Cu NCs,the composite Cu NCs/CSNPs exhibited an increased quantum yield and enhanced fluorescence sensing performance.Based on the composite Cu NCs/CSNPs,a fluorescence method for the detection of cefixime fluorescence quenching was estab-lished.The technique was simple,sensitive,and selective for detecting cefixime.The fluorescence quenching effi-ciency of Cu NCs/CSNPs was linearly related to the concentration of cefixime in the range of 3.98-38.5µmol·L^(-1)(1.81-17.46 mg·L^(-1)),with a limit of detection of 0.0455µmol·L^(-1)(20.6µg·L^(-1)). 展开更多
关键词 copper nanoclusters fluorescence detection CEFIXIME
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Nanoflower Copper Sulfide as Cathode Materials for Magnesium Ion Batteries
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作者 He Yuantai Wu Liang +3 位作者 Shi Yongan Zhong Zhiyong Yao Wenhui Pan Fusheng 《稀有金属材料与工程》 北大核心 2025年第3期545-553,共9页
CuS-C50,the cathode materials for magnesium ion batteries,was synthesized by adding the surfactant cetyltrimethyl ammonium bromide(CTAB)and adjusting the percentage of ethylene glycol to 50vol%in hydrothermal synthesi... CuS-C50,the cathode materials for magnesium ion batteries,was synthesized by adding the surfactant cetyltrimethyl ammonium bromide(CTAB)and adjusting the percentage of ethylene glycol to 50vol%in hydrothermal synthesis process.Results show that CuS-C50 has the complete nanoflower structure.In aluminum chloride-pentamethylcydopentodiene/tetrahydrofuran(APC/THF)electrolyte,the CuS-C50 exhibits a high specific capacity of 331.19 mAh/g when the current density is 50 mA/g and still keeps a specific capacity of 136.92 mAh/g over 50 cycles when the current density is 200 mA/g.Results of morphology characterizations indicate that the complete nanoflower structure can provide more active sites and reduce the barriers for Mg^(2+)movement,eventually improving the charge and discharge performance of the CuS cathode materials for magnesium ion batteries. 展开更多
关键词 copper sulfide nanoflower magnesium ion batteries CTAB hydrothermal synthesis
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Hot Deformation Behavior and Microstructure Evolution of Electrolytic Copper
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作者 Zhang Han Sang Chen +3 位作者 Zhang Yan Xu Yangtao Qiao Jisen Xia Tiandong 《稀有金属材料与工程》 北大核心 2025年第4期920-929,共10页
The hot deformation behavior of electrolytic copper was investigated using a Gleeble-3500 thermal simulation testing machine at temperatures ranging from 500℃ to 800℃ and strain rates ranging from 0.01 s^(-1) to 10 ... The hot deformation behavior of electrolytic copper was investigated using a Gleeble-3500 thermal simulation testing machine at temperatures ranging from 500℃ to 800℃ and strain rates ranging from 0.01 s^(-1) to 10 s^(-1),under 70% deformation conditions.The true stress-true strain curves were analyzed and a constitutive equation was established at a strain of 0.5.Based on the dynamic material model proposed by Prasad,processing maps were developed under different strain conditions.Microstructure of compressed sample was observed by electron backscatter diffraction.The results reveal that the electrolytic copper demonstrates high sensitivity to deformation temperature and strain rate during high-temperature plastic deformation.The flow stress decreases gradually with raising the temperature and reducing the strain rate.According to the established processing map,the optimal processing conditions are determined as follows:deformation temperatures of 600-650℃ and strain rates of 5-10 s^(-1).Discontinuous dynamic recrystallization of electrolytic copper occurs during high-temperature plastic deformation,and the grains are significantly refined at low temperature and high strain rate conditions. 展开更多
关键词 electrolytic copper hot deformation constitutive equation dynamic recrystallization
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In situ synthesis,crystal structure,and magnetic characterization of a trinuclear copper complex based on a multi-substituted imidazo[1,5-a]pyrazine scaffold
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作者 WANG Zhaodong 《无机化学学报》 北大核心 2025年第3期597-604,共8页
A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]py... A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]pyrazine scaffold was serendipitously prepared from the reaction of the pro-ligand of H_(2)L1(N,N'-bis(pyrazin-2-ylmethyl)pyrazine-2,3-dicarboxamide) with CuSO_(4)·5H_(2O) in aqueous solution at room temperature.Complex 1 was characterized by IR,single-crystal X-ray analysis,and magnetic susceptibility measurements.Single-crystal X-ray analysis reveals that the complex consists of three Cu(Ⅱ) ions,two in situ transformed L2~-ligands,two coordinated sulfates,seven coordinated water molecules,and eight uncoordinated water molecules.Magnetic susceptibility measurement indicates that there are obvious ferromagnetic coupling interactions between the adjacent Cu(Ⅱ) ions in 1.CCDC:1852713. 展开更多
关键词 amide ligand copper complex single crystal structure C-N coupling magnetic characterization
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Copper and iron extraction from chalcopyrite by NaCl@MgCl_(2)@urea:Synthesis of CuFe_(2)O_(4) electrodes for supercapacitors
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作者 POLAT Safa MOHAMMED Mariem MASHRAH Muwafaq 《Journal of Central South University》 2025年第1期82-93,共12页
This study was conducted in two sections.Initially,the effects of NaCl,MgCl_(2),and urea were investigated on extracting copper and iron from chalcopyrite.Subsequently,CuFe_(2)O_(4)-based electrodes for supercapacitor... This study was conducted in two sections.Initially,the effects of NaCl,MgCl_(2),and urea were investigated on extracting copper and iron from chalcopyrite.Subsequently,CuFe_(2)O_(4)-based electrodes for supercapacitors were synthesized using the extracted solution.The first phase revealed that 3 mol/L NaCl achieved the highest extraction performance,yielding 60%Cu and 23%Fe.MgCl_(2)at 1.5 mol/L extracted 52%Cu and 27%Fe,while a combination of 0.5 mol/L MgCl_(2)and 1.6 mol/L urea yielded 57%Cu and 20%Fe.Urea effectively reduced iron levels.CuFe_(2)O_(4)-based electrodes were then successfully synthesized via a hydrothermal method using a MgCl_(2)-urea solution.Characterization studies confirmed CuFe_(2)O_(4)formation with a 2D structure and 45−50 nm wall thickness on nickel foam.Electrochemical analysis showed a specific capacitance of 725 mF/cm^(2)at 2 mA/cm^(2)current density,with energy and power densities of 12.3 mW·h/cm^(2)and 175 mW/cm^(2),respectively.These findings suggest that chalcopyrite has the potential for direct use in energy storage. 展开更多
关键词 copper IRON NACL MgCl_(2) UREA thiourea CHALCOPYRITE supercapacitor copper ferrite
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Study on the Borylation of β-C Positions of Aryl Olefins Catalyzed by Copper Organophosphorus Complexes
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作者 Du Shunli Wang Yaya +2 位作者 Guo Jiaming Xu Xuewei Peng Xinhua 《有机化学》 北大核心 2025年第7期2435-2443,共9页
Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron... Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron source and Cu^(Ⅱ) organophosphorus complex(L)as the catalyst can effectively realize the hydrogen-reduced borylation products and dehydrohydrated borylation products of aryl olefins.The reaction regioselectivity involvingβ-C positions of aryl olefins can be controlled by regulating the ligand and additive types.The formation mechanism of the product is conducted at LCu^(Ⅰ)Bpin formed from Cu^(Ⅱ),L and B_(2)pin_(2).Subsequently the substrate aryl olefins undergo addition reaction to form the active intermediate PhCH(LCu^(Ⅰ))CH_(2)Bpin.Followed by the metathesis of the active intermediate with water to form hydrogen reduction products,the same active intermediate can be oxidized with 2,2,6,6-tetramethylpiperidoxyl(TEMPO)to form trans dehydrogenation products. 展开更多
关键词 arylenes bis(pinacolato)diboron copper organic phosphine complex hydrogenative borylation reduction boron dehydrogenation oxidation
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Metabolomic Changes in Mice Induced by Copper Exposure:Systematic Analysis and Exploration of Toxicity Mechanisms
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作者 Shuai Xiao Linqiang Gong +7 位作者 Shiyuan Zhao Xue Chu Fengfeng Li Yazhou Zhang Fangqiang Song Pei Jiang Gang Ding Shuai Tang 《Biomedical and Environmental Sciences》 2025年第1期106-118,共13页
Copper is one of the essential trace elements for living beings,influencing several critical processes like cellular energy production,antioxidant defense,communication within cells,and the functioning of enzymes[1].T... Copper is one of the essential trace elements for living beings,influencing several critical processes like cellular energy production,antioxidant defense,communication within cells,and the functioning of enzymes[1].The daily intake of copper is 0.7−3.0 mg/d,and copper homeostasis is strictly regulated by physiological processes,including duodenal and small intestinal uptake,blood transport,liver storage and release,and bile excretion,thereby maintaining copper homeostasis in the body[2],and many studies have confirmed that copper disorders in the body are associated with neurodegenerative,metabolic,and genetic diseases[3]. 展开更多
关键词 copper HOMEOSTASIS thereby
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2024 Annual Report of China Mineral Resources (copper, gold, coal, etc.)
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作者 Li-qiong Jia Xi-jie Chen Zi-guo Hao 《China Geology》 2025年第1期235-236,共2页
In October 2024,the Ministry of Natural Resources of PRC released the 2024 China Mineral Resources Report,which focuses on new progress since 2023 in the geological and mineral survey and evaluation,mineral resource e... In October 2024,the Ministry of Natural Resources of PRC released the 2024 China Mineral Resources Report,which focuses on new progress since 2023 in the geological and mineral survey and evaluation,mineral resource exploration and development,mine ecological restoration,green mine construction,new changes in mineral resource policies and regulations,new measures in mineral resource management,new situations in scientific and technological innovation,as well as the new achievements of the international geological and mineral cooperation. 展开更多
关键词 GOLD copper RESOURCE
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