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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
Effect of direct current electric field (DCEF) on corrosion behaviour of copper printed circuit board (PCB-Cu), Cl-ion migration behaviour, dendrites growth under thin electrolyte layer was investigated using pote...Effect of direct current electric field (DCEF) on corrosion behaviour of copper printed circuit board (PCB-Cu), Cl-ion migration behaviour, dendrites growth under thin electrolyte layer was investigated using potentiodynamic polarization and scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS). Results indicate that DCEF decreases the corrosion of PCB-Cu;Cl-ions directionally migrate from the negative pole to the positive pole, and enrich on the surface of the positive pole, which causes serious localized corrosion; dendrites grow on the surface of the negative pole, and the rate and scale of dendrite growth become faster and greater with the increase of external voltage and exposure time, respectively.展开更多
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
Cu, As, Sb and Bi in copper electrolyte could be efficiently removed by reducing with SO2 followed by evaporative crystallization. As2O3 and CuSO4·5H2O were obtained after crystallized product was treated by diss...Cu, As, Sb and Bi in copper electrolyte could be efficiently removed by reducing with SO2 followed by evaporative crystallization. As2O3 and CuSO4·5H2O were obtained after crystallized product was treated by dissolution, oxidation, neutralization, sedimentation, filtration and evaporative crystallization. The removal rates of Cu, As, Sb and Bi are 87.1%, 83.9%, 21.0% and 84.7%, respectively, when As (Ⅴ) in copper electrolyte is fully reduced to As (Ⅲ) by SO2, and the H2SO4 in concentrated copper electrolyte is 645 g/L. The removal rate of As is 92.81% when 65 g crystallized product is dissolved in 200 mL water at 30 ℃. The CuSO4·5H2O content is 98.8% when the filtrate is purified under the conditions that n(Fe):n(As) is 1.2, the dosage of H2O2 is 19 times the stoichiometric needed, temperature is 45 ℃, time is 40 min, pH is 3.7, and then is evaporation crystallized.展开更多
基金Supported by Key Technologies R&D Programme(No.2003BA614A-02)
文摘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.
文摘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.
基金supported by the Notional Natural Science Foundation of Chino,No.82160690Colloborotive Innovation Center of Chinese Ministry of Education,No.2020-39Science and Technology Foundation of Guizhou Province,No.ZK[2021]-014(all to FZ)。
文摘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.
文摘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.
文摘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.
基金supported financially by the National Natural Science Foundation of China (22302222, 22072172)the Postdoctoral Science Foundation (2024T170965, 2023M743641)+5 种基金the Youth Innovation Promotion Association CAS (Y2021056)Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy (YLU-DNL Fund 2022007)the Major Science and Technology Projects of Shanxi Province (202005D121002)the Special Fund for Science and Technology Innovation Teams of Shanxi Province (202304051001007)the Science and Technology Department of Shanxi Province (202303021222409)the Shanxi Provincial Department of Human and Social Resources Security’s Doctor Introduction Program (2024SHB001)
文摘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.
基金supported by the DST(DST-WTIDST/TMD/EWO/WTI/DM/2021/283,DST-SYST,and DSTinspire faculty award)and Science and Engineering Research Board(SERB+1 种基金No.CRG/2019/005280)the Indian Institute of Technology Bombay(IITB)for their funding support for this work.ND and AMN acknowledge the Ministry of Education,India,for their doctoral fellowship support.We thank Prof.Suparna Mukherjee at IIT Bombay for kindly providing us with the host E.coli C3000(No.ATCC 15597).
文摘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.
文摘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.
文摘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.
基金the W.M.Keck Center for Nano-Scale Imaging in the Department of Chemistry and Biochemistry at the University of Arizona(Grant No.RRID:SCR_022884),with funding from the W.M.Keck Foundation Grant.
文摘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.
基金supported by the National Key R&D Plan Program of China(No.2021YFB3400800)Henan Key Research and Development Program(No.231111241000)+1 种基金the Joint Fund of Henan Province Science and Technology R&D Program(No.225200810026)Zhongyuan Scholar Workstation Funded Program(No.224400510025).
文摘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.
基金supported by the National Natural Science Foundation of China(Nos.52070103 and 22102102)Zhejiang Provincial Natural Science Foundation of China(Nos.LY21E090004 and LQ22B050004)+1 种基金Ningbo Public Welfare Science and Technology Program(No.2021S025)Ningbo Youth Leading Talent Project(No.2024QL038).
文摘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.
文摘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.
基金National Natural Science Foundation of China(52171101)Fundamental Research Funds for the Central Universities(2024IAIS-QN009)National Key R&D Program of China(2021YFB3701100)。
文摘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.
基金Gansu Province Higher Education Institutions Industrial Support Program Project(2022CYZC-19)Gansu Provincial Science and Technology Major Project(22ZD6GA008)。
文摘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.
文摘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.
文摘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)).
基金Project(50871044)supported by the National Natural Science Foundation of ChinaProject(2012M511207)supported by the Postdoctoral Science Foundation of ChinaProject(10122011)supported by the Science Research Foundation of Wuhan Institute Technology,China
文摘Effect of direct current electric field (DCEF) on corrosion behaviour of copper printed circuit board (PCB-Cu), Cl-ion migration behaviour, dendrites growth under thin electrolyte layer was investigated using potentiodynamic polarization and scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS). Results indicate that DCEF decreases the corrosion of PCB-Cu;Cl-ions directionally migrate from the negative pole to the positive pole, and enrich on the surface of the positive pole, which causes serious localized corrosion; dendrites grow on the surface of the negative pole, and the rate and scale of dendrite growth become faster and greater with the increase of external voltage and exposure time, respectively.
文摘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.
文摘Cu, As, Sb and Bi in copper electrolyte could be efficiently removed by reducing with SO2 followed by evaporative crystallization. As2O3 and CuSO4·5H2O were obtained after crystallized product was treated by dissolution, oxidation, neutralization, sedimentation, filtration and evaporative crystallization. The removal rates of Cu, As, Sb and Bi are 87.1%, 83.9%, 21.0% and 84.7%, respectively, when As (Ⅴ) in copper electrolyte is fully reduced to As (Ⅲ) by SO2, and the H2SO4 in concentrated copper electrolyte is 645 g/L. The removal rate of As is 92.81% when 65 g crystallized product is dissolved in 200 mL water at 30 ℃. The CuSO4·5H2O content is 98.8% when the filtrate is purified under the conditions that n(Fe):n(As) is 1.2, the dosage of H2O2 is 19 times the stoichiometric needed, temperature is 45 ℃, time is 40 min, pH is 3.7, and then is evaporation crystallized.