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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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Copper homeostasis and neurodegenerative diseases
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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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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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Tsedong Copper Wares:Handicrafts of Ingenuity and Artistic Charm
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作者 Zhang Yu(Text/Photos) Wang Yandan(Text/Photos) Huang Wenjuan(Translated) 《China's Tibet》 2025年第3期30-33,共4页
In the early morning,the constant jingling and crackling echoed through the deep valley of Aima Township,Namling County,Xigaze City,where a group of apprentices at the Tsedong Gold-Copper Buddha Statue Center for Anci... In the early morning,the constant jingling and crackling echoed through the deep valley of Aima Township,Namling County,Xigaze City,where a group of apprentices at the Tsedong Gold-Copper Buddha Statue Center for Ancient Craftsmanship and Technique were diligently creating their handcrafted works. 展开更多
关键词 namling county xigaze city HANDICRAFTS aima township Tsedong copper wares ancient craftsmanship gold copper buddha statue center technique
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Regulation of the copper bulk phase within the Cu-CeO_(2)catalyst for the selectivity shift in electrochemical reduction of CO_(2)
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作者 Lei Xue Yuansong Zhao +4 位作者 Yuntao Qi Guilan Fan Shanghong Zeng Yong Qin Bin Zhang 《Journal of Energy Chemistry》 2025年第8期759-767,共9页
The copper-cerium catalysts demonstrate high efficiency in CO_(2)reduction reactions(CO_(2)RR).However,the mechanism governing the formation of C_(2)H_(4)and CH_(4)by regulating Cu bulk phase structure at the copper-c... The copper-cerium catalysts demonstrate high efficiency in CO_(2)reduction reactions(CO_(2)RR).However,the mechanism governing the formation of C_(2)H_(4)and CH_(4)by regulating Cu bulk phase structure at the copper-cerium interface remains unclear due to the instability and dynamic evaluations of copper species.Herein,we synthesized CeO_(2)-CuO containing solely Cu^(2+)species and CeO_(2)-Cu featuring predominantly metallic Cu species at the interface,which exhibit stable structures under various potentials,offering ideal models for in-depth mechanistic studies.The C_(2)H_(4)is the main product over the CeO_(2)-CuO catalyst,exhibiting a Faradaic efficiency(FE)of 42.3%±1.4%,while CH_(4)is the primary product over the CeO_(2)-Cu catalyst,with a FE of 32.4%±1.3%.These results demonstrate that regulating bulk phase Cu structure at the copper-cerium interface influences the selectivity of hydrocarbon products.The operando ATR-SEIRAS finds that CeO_(2)-CuO surfaces with single linear*CO adsorption are advantageous for synthesizing*COCO,whereas bridge-bonded*CO adsorption promoted*CHO formation.Furthermore,DFT simulations demonstrate that the energy barrier of CO-CO coupling(C_(2)H_(4)pathway)at the CeO_(2)-CuO interface decreases as compared to the CeO_(2)-Cu catalyst,thus indicating a facilitated conversion of the CO_(2)to C_(2)H_(4).This research deepens the mechanistic understanding of the copper-cerium system during CO_(2)RR and effectively formulates a strategy for developing high-selectivity catalysts. 展开更多
关键词 copper cerium Bulk phase copper structure Reaction mechanism CO_(2)reduction reactions
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Enhanced bacterial and virus disinfection with copper nanoparticle optimized LIG composite electrodes and filters
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作者 Nandini Dixit Akhila M.Nair Swatantra P.Singh 《Journal of Environmental Sciences》 2025年第6期623-636,共14页
Waterborne pathogens pose a lifelong threat, necessitating advanced disinfection systemswith state-of-the-art materials. Laser-Induced Graphene (LIG), a 3-dimensional form ofgraphene, is a widely known electrode mater... Waterborne pathogens pose a lifelong threat, necessitating advanced disinfection systemswith state-of-the-art materials. Laser-Induced Graphene (LIG), a 3-dimensional form ofgraphene, is a widely known electrode material for its electrically-induced antimicrobialproperties. However, LIG surfaces exhibit antimicrobial properties exclusively in the presenceof electricity. In this work, copper-doped LIG (Cu-LIG) composite electrodes and filterswere developed with enhanced antimicrobial properties in single-step laser scribing. Thework emphasizes the optimization of copper doping with LIG for both electrical and nonelectrical-based disinfection. The copper doping was optimized to a minimal concentration(∼1%) just to enhance the electrochemical properties of LIG. Furthermore, the excess additionof copper was helpful towards non-electricity-based treatment without significantleaching. The prepared surfaces were tested in both electrodes and filter configuration andshowed excellent antibacterial and antiviral activity against mixed bacterial culture and amodel enteric virus, MS2 bacteriophage. On the application of 2.5 V with Cu-LIG electrodes,6-log removal of bacteria and virus was achieved. Furthermore, the membrane-based electroconductivefilters were tested in a flow-through configuration and demonstrated 6-logremoval at 2.5 V with a flux of ∼ 500 (L·m^(2))/h with both bacteria and viruses at minimumenergy expense. Additionally, reactive oxygen species scavenging and hydrogen peroxidegeneration experiments have confirmed the role of electrical effects and indirect oxidationon the inactivation mechanism. The prepared Cu-LIG composite surfaces showed potentialfor environmental remediation applications. 展开更多
关键词 Electrochemical Disinfection copper-doped LIG Electroconductive filtration copper nanoparticle optimization Enhanced electrocatalytic activity
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Role of copper in central nervous system physiology and pathology 被引量:2
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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:1
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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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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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Performance of stabilized copper mine tailings with freeze-thaw and wet-dry seasonal cycles 被引量:1
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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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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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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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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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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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Correction to: Tuning dual three-dimensional porous copper/graphite composite to achieve diversified utilization of copper current collector for lithium storage
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作者 Xia Ma Zhi-Jia Zhang +7 位作者 Jia-Min Wang Shi-Hao Sun Shao-Fei Zhang Shen Yuan Zhi-Jun Qiao Zhen-Yang Yu Jian-Li Kang Wei-Jie Li 《Rare Metals》 2025年第2期1409-1409,共1页
In the original publication, incomplete Fig. 1 has been published. The correct version of Fig. 1 is provided in this correction.
关键词 GRAPHITE tuning COMPOSITE three dimensional current collector POROUS DUAL copper
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Merging catalytic electron donor-acceptor complex and copper catalysis: Enantioselective radical carbocyanation of alkenes
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作者 Hongping Zhao Weiming Yuan 《Chinese Chemical Letters》 2025年第10期235-240,共6页
Catalytic electron donor-acceptor(EDA) complex photochemistry has recently emerged as a popular and sustainable alternative to photoredox synthetic methods. Yet, the catalytic EDA strategy is still in its infancy for ... Catalytic electron donor-acceptor(EDA) complex photochemistry has recently emerged as a popular and sustainable alternative to photoredox synthetic methods. Yet, the catalytic EDA strategy is still in its infancy for organic synthesis due to the challenges of designing novel catalytic paradigm and expanding the substrate and reaction scope. Here, we disclose a catalytic EDA/Cu cooperative strategy by employing Na I as a catalytic donor for copper-catalyzed radical asymmetric carbocyanation. A diverse range of synthetically useful chiral benzyl nitriles are produced with high enantioselectivities. This synergetic EDA/copper catalysis enables the decarboxylative cyanation without request of any photoredox catalysts, further expanding the synthetic potential of catalytic EDA chemistry in organic synthesis. 展开更多
关键词 PHOTOCHEMISTRY Catalytic EDA complex copper Carbocyanation ALKENES
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Panax ginseng protects against copper sulfate-induced kidney toxicity in rats
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作者 Ozay Gules Mustafa Yildiz +2 位作者 Murat Boyacioglu Alper Sevimli Belma Dayi 《Asian Pacific Journal of Tropical Biomedicine》 2025年第11期465-474,I0007,共11页
Objective:To assess the protective effects of Panax ginseng(PG)against copper sulfate(CuSO_(4))-induced kidney toxicity in rats.Methods:The rats were randomly allocated into four groups:control,CuSO_(4),PG,and PG+CuSO... Objective:To assess the protective effects of Panax ginseng(PG)against copper sulfate(CuSO_(4))-induced kidney toxicity in rats.Methods:The rats were randomly allocated into four groups:control,CuSO_(4),PG,and PG+CuSO_(4).The experiment continued for 14 days,during which CuSO_(4) was provided at a dosage of 100 mg/kg body weight per day and PG at 300 mg/kg body weight by oral gavage per day.Upon completion of the experiment,kidney sections were used for histological and histomorphometric analyses.The histochemical method was applied to ascertain the density of the glomerular mesangial matrix.The expressions of vascular endothelial growth factor(VEGF)and caspase-3 were examined using immunohistochemistry.The levels of malondialdehyde and glutathione,along with the activity of superoxide dismutase and catalase in the kidney,were measured.Results:PG treatment exhibited a marked protective effect against CuSO_(4)-induced renal damage,as evidenced by improved histopathological lesions,significantly reduced glomerular mesangial matrix density,VEGF in distal tubules,caspase-3 expression,and malondialdehyde levels in renal tissue,as well as enhanced superoxide dismutase and catalase activities.Conclusions:PG treatment ameliorates CuSO_(4)-induced kidney injury in rats.Further studies are warranted to verify its efficacy and elucidate the underlying mechanism of its nephroprotective action. 展开更多
关键词 copper sulfate KIDNEY Panax ginseng VEGF ANTIOXIDANT
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Mass spectrometry for non-destructive detection of the average diameter of micro copper wires
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作者 Rui Su Xiaowei Fang +5 位作者 Peng Zeng Yong Qian Xuanzhu Li Huiyu Xing Jiamei Lin Jiaquan Xu 《Chinese Chemical Letters》 2025年第10期474-477,共4页
The performance and price of copper-based micro linear products are determined by the diameter uniformity.How to accurately detect the wire diameter of long-length copper based micro linear products without cutting or... The performance and price of copper-based micro linear products are determined by the diameter uniformity.How to accurately detect the wire diameter of long-length copper based micro linear products without cutting or damage has always been a technical concern for production enterprises.Herein,a novel approach was developed for nondestructive detection of the average diameter at any given segment of a long copper wire by assessing the adsorption capacity of arginine on its surface.The amount of adsorbent on the surface of the copper wire exhibits a positive correlation with the area,which can be detected by extractive electrospray ionization mass spectrometry(EESI-MS)after online elution with ammonia.The experimental results demonstrated that the analysis can be completed within 15 min,with a good linear relationship between copper wires with different diameters and the adsorption capacity of arginine.The linear correlation coefficient R2was 0.995,the relative standard deviation was 1.10%-2.81%,and the detection limit reached 2.5μm(length of segment=4 cm),showing potential applications for facile measurement of the average diameter of various metal wires. 展开更多
关键词 Measurement of diameter Mass spectrometry Non-destructive detection copper wire Average diameter Measurement of diameter Mass spectrometry Non-destructive detection copper wire Average diameter
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