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Influence of contact layer on the sulphur corrosion of copper conductors in power transformers

High Voltage 2022年第1期7卷 176-184页

作者： Lijun Yang Dong Ding Yuan Yuan Sihang Gao Yuncai Lu State Key Laboratory of Power Transmission Equipment and System Security and New Technology Chongqing UniversityChongqingChina College of Material Science and Engineering Chongqing UniversityChongqingChina Key Laboratory of Industrial Internet of Things and Networked Control Ministry of EducationChongqing University of Posts and TelecommunicationsChongqingChina State Grid Jiangsu Electric Power Co. Ltd.Electric Power Research InstituteNanjingChina

Owing to the corrosive sulphides in the mineral insulating oil such as dibenzyl disul-phide(DBDS),copper windings in oil‐immersed transformers may suffer sulphur corrosion.This study investigates the influence of different contact conditions on the corrosion of copper conductors in transformers.Oil‐immersed accelerated corrosion experiment was conducted on copper conductors with various contact materials and different layers of insulating paper.The surface micromorphology,deposition compo-nent and the potentiodynamic polarization characteristics of copper conductors were explored.The results show that copper with different contact materials suffer sulphur corrosion;conversely,bare copper rarely does.It was also verified that the existence of a particular gap between copper and contact layer is a significant factor in sulphur corrosion by the formation of a concentration cell on the copper surface.The insu-lating paper wrapped around copper conductors does not increase the corrosion ten-dency of copper;however,it contributes to the formation of a region concentrated with DBDS,Cu^(2+),H^(+)by adsorption and impediment,which plays a key role in facilitating the sulphur corrosion of copper conductors.Moreover,sulphur corrosion can also occur on other metal parts in transformers when there is a particular gap on surfaces other than copper.

关键词： corrosion copper sulphur

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Recent Advances in Domino Synthesis of Fused Polycyclic N-Heterocycles Based on Intramolecular Alkyne Hydroamination under copper Catalysis

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Chinese Journal of Chemistry 2023年第24期41卷 3751-3771页

作者： Zefeng Jin Guodong Shen Xin Lv Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhuaZhejiang321004 China School of Chemistry and Chemical Engineering Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell TechnologyLiaocheng UniversityLiaochengShandong252059 China

Fused polycyclic N-heterocycles are very important scaffolds in biomedicinal chemistry and materials science.Intramolecular alkyne hydroamination is a powerful method for the construction of N-heterocycles.In the last two decades,copper-catalyzed domino reactions based on intramolecular alkyne hydroamination has emerged as a robust strategy for assembling various fused polycyclic N-heterocycles.Great progress has been achieved in this area.This short review covers the advances made in copper-catalyzed domino synthesis of fused polycyclic N-heterocycles based on the strategy from 2008 to 2023,and will hopefully serve as an inspiration towards the exploration of new copper-catalyzed versions of the transformation.The domino transformations are introduced and discussed from five aspects according to the different key processes involved in these reactions.

关键词： Domino reactions Polycyclic N-heterocycles Fused-ring systems Intramolecular hydroamination Alkynes copper Cyclization Synthetic methods

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A new insight on copper:Promotion of collagen synthesis and myofiber growth and development in juvenile grass carp(Ctenopharyngodon idella)

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Animal Nutrition 2023年第4期15卷 22-33页

作者： Rui Ma Lin Feng Pei Wu Yang Liu Hong-Mei Ren Shu-Wei Li Ling Tang Cheng-Bo Zhong Dong Han Wen-Bing Zhang Jia-Yong Tang Xiao-Qiu Zhou Wei-Dan Jiang Animal Nutrition Institute Sichuan Agricultural UniversityChengdu611130China Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengdu611130China Key Laboratory of Animal Disease-Resistance Nutrition Ministry of EducationMinistry of Agriculture and Rural AffairsKey Laboratory of Sichuan ProvinceSichuan611130China Animal Nutrition Institute Sichuan Academy of Animal ScienceSichuan Animtech Feed Co.LtdChengdu610066SichuanChina State Key Laboratory of Fresh Water Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan430072China The Key Laboratory of Mariculture Ministry of EducationThe Key Laboratory of Aquaculture Nutrition and FeedsMinistry of AgricultureOcean University of ChinaQingdao266003China

copper(Cu)is a trace element,essential for fish growth.In the current study,in addition to growth performance,we first explored the effects of Cu on collagen synthesis and myofiber growth and development in juvenile grass carp(Ctenopharyngodon idella).A total of 1080 fish(11.16±0.01 g)were randomly divided into 6 treatments(3 replicates per treatment)to receive five doses of organic Cu which were Cu citrate(CuCit)at 0.99(basal diet),2.19,4.06,6.15,and 8.07 mg/kg,and one dose o inorganic Cu(CuSO_(4)·5H_(2)O at 3.15 mg/kg),for 9 weeks.The results showed appropriate Cu level(4.06 mg kg)enhanced growth performance,improved nutritional Cu status,and downregulated Cu-transporting ATPase 1 mRNA levels in the hepatopancreas,intestine,and muscle of juvenile grass carp.Meanwhile collagen content in fish muscle was increased after Cu intake,which was probably due to the following pathways:(1)activating CTGF/TGF-β1/Smads signaling pathway to regulate collagen transcription;(2upregulating of La ribonucleoprotein domain family 6(LARP6)mRNA levels to regulate translation initiation;(3)increasing proline hydroxylase,lysine hydroxylase,and lysine oxidase activities to regulate posttranslational modifications.In addition,optimal Cu group increased myofiber diameters and the frequency of myofibers with diameter>50μm,which might be associated with upregulation of cyclin B cyclin D,cyclin E,proliferating cell nuclear antigen,myogenic determining factor(MyoD),myogenic factor 5,myogenin(MyoG),myogenic regulatory factor 4 and myosin heavy chain(MyHC)and down regulation of myostatin mRNA levels,increasing protein levels of MyoD,MyoG and MyHC in fish muscle Finally,based on percentage weight gain(PWG),serum ceruloplasmin(Cp)activity and collagen conten in fish muscle,Cu requirements were determined as 4.74,4.37 and 4.62 mg/kg diet(CuCit as Cu source of juvenile grass carp,respectively.Based on PWG and Cp activity,compared to CuSO_(4)·5H_(2)O,the efficacy of CuCit were 131.80%and 115.38%,respectively.Our findings provide new insights into

关键词： copper Grass carp(Ctenopharyngodon idella) Collagen synthesis Myofiber

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A Novel laser scanning method for metallization of alumina substrate by copper

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Rare Metals 2023年第3期42卷 844-852页

作者： Yu Hui Zhao-Lin Na Bo-Ming Sun Xu-Dong Sun Jia-Lin Chen Liaoning Engineering Laboratory of Special Optical Functional Crystals College of Environmental and Chemical EngineeringDalian University Department of Chemistry Imperial College LondonLondon W120BZUK Institute of Ceramics and Powder Metallurgy School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals Kunming Institute of Precious MetalsKunming 650106China

A laser scanning method was developed to metalize the surface of alumina substrates with copper.The modeling of the heating and cooling rates of the samples during the laser scanning process indicates that the metallization process involves the rapid melting and solidification of Al_(2)O_(3) and Cu and the evaporation and deposition of part of the Cu.The surface of the metalized alumina substrate was composed of copper spheres(~60μm in diameter)embedded into the alumina substrate and a thin layer of CuAlO_(2).

关键词： solidification copper laser

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Multi-fluorous-included Counter Anions-based Ionic Copolymers:Synthesis and Enhanced Hydrophobic Adsorption Films on copper Surface for Super Protection

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Chemical Research in Chinese Universities 2023年第5期39卷 845-856页

作者： REN Weihua SHI Yueting CHEN Lingli YANG Song ZHANG Shengtao LIU Xiaohong REN Xiaolei LI Hongru College of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044P.R.China Chongqing Youth Vocational&Technical College Chongqing 400712P.R.China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714P.R.China College of Environment and Resources Chongqing Technology and Business UniversityChongqing 401331P.R.China

Three multi-fluorous-carried anions-based ionic copolymers(ICs)including(fluorosulfonyl)imide(FSI-),(trifluorometha-nesulfonyl)imide(TFSI-)and hexafluorophosphate anions(PF6-)(IC[FSI-]),poly[1,1'-(butane-1,4-diyl)bis(3-pentyl-1H-imidazol-3-ium)bis(fluorosulfonyl)amide](IC[TFSI-]),poly{1,1'-(butane-1,4-diyl)bis(3-pentyl-1H-imidazol-3-ium)bis[(trifluoromethyl)sulfonyl]-amide}(IC[PF6-]),poly[1,1'-(butane-1,4-diyl)bis(3-pentyl-1H-imidazol-3-ium)bishexafluorophosphate]were synthesized with a simple ionic exchange method by using amphiphilic poly[1,1'-(butane-1,4-diyl)bis(3-pentyl-1H-imidazol-3-ium)bisbromide](IC[Br-])as the intermediate ionic polymer.The chemical srutrcures of the target ICs were characterized by nuclear magnetic resonance(NMR)spectroscopy and Fourier-transform infrared spectroscopy(FTIR).It is shown that the target ICs could be spontaneously adsorbed on copper surface in N,N-dimethflormamide(DMF),and the tight adsorption films were formed on metal surface.The contacting angles suggest that the formed adsorption layers of target ICs on copper surface were characterized with hydrophobic nature.Furthermore,the target ICs-copper chemistry bonding was confirmed by various means.The electrochemistry analysis showed that the target ICs adsorption layers could prevent from copper corrosion in H2SO4solution efficiently,and the maximal anticorrosion efficiency was over 95%at 0.100 g/L.In particular,the target ICs showed 85%or above anticorrosion efficiency for copper at a low concentration of 0.025 g/L,which was greater than the intermediate polymer IC[Br-].In addition,an insight of mixed chemisorption and physisorption of the target ICs on metal surface was analyzed and discussed.

关键词： Hydrophobic adsorption film Ionic copolymer Multi-fluorous-included anion copper Anticorrosion

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Causal Effect of Genetically Determined Blood copper Concentrations on Multiple Diseases: A Mendelian Randomization and Phenome-Wide Association Study

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Phenomics 2022年第4期2卷 242-253页

作者： Xiuming Feng Wenjun Yang Lulu Huang Hong Cheng Xiaoting Ge Gaohui Zan Yanli Tan Lili Xiao Chaoqun Liu Xing Chen Zengnan Mo Longman Li Xiaobo Yang Department of Occupational Health and Environmental Health Guangxi Medical UniversityNanning 530021GuangxiChina Guangxi Key Laboratory for Genomic and Personalized Medicine Center for Genomic and Personalized MedicineGuangxi Collaborative Innovation Center for Genomic and Personalized MedicineGuangxi Medical UniversityNanning 530021GuangxiChina Collaborative Innovation Centre of Regenerative Medicine and Medical BioResource Development and Application Co-constructed by the Province and Ministry Guangxi Medical UniversityNanning 530021GuangxiChina Department of Radiotherapy The First Affiliated Hospital of Guangxi Medical UniversityNanningGuangxi 530021China Department of Public Health School of MedicineGuangxi University of Science and TechnologyGuangxi 545006China Department of Nutrition and Food Hygiene School of Public HealthGuangxi Medical UniversityNanningGuangxiChina School of Public Health Guangxi Medical UniversityNanningGuangxiChina Department of Urology Institute of Urology and NephrologyFirst Affiliated Hospital of Guangxi Medical UniversityNanningGuangxi 530021China

Exposures to copper have become a health concern.We aim to explore the broad clinical effects of blood copper concentrations.A total of 376,346 Caucasian subjects were enrolled.We performed a Mendelian randomization and phenome-wide association study(MR-PheWAS)to evaluate the causal association between copper and a wide range of outcomes in UK Biobank,and we constructed a protein-protein interaction network.We found association between blood copper concentrations and five diseases in the overall population and nine diseases in male.MR analysis implicated a causal role of blood copper in five diseases(overall population),including prostate cancer(OR=0.87,95%CI 0.77-0.98),malignant and unknown neoplasms of the brain and nervous system(OR=0.58,95%CI 0.38-0.89),and hypertension(OR=0.94,95%CI 0.90-0.98),essential hypertension(OR=0.94,95%CI 0.90-0.98)and cancer of brain and nervous system(OR=0.63,95%CI 0.41-0.98).For male,except for dysphagia being newly associated with blood copper(OR=1.39,95%CI 1.18-1.63),other MR results were consistent with the overall population.In addition,the PPI network showed possible relationship between blood copper and four outcomes,namely brain cancer,prostate cancer,hypertension,and dysphagia.Blood copper may have causal association with prostate cancer,malignant and unknown neoplasms of the brain and nervous system,hypertension,and dysphagia.Considering that copper is modifiable,exploring whether regulation of copper levels can be used to optimize health outcomes might have public health importance.

关键词： copper Disease Mendelian randomization Phenome-wide association study

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Single-atom alloying sprinkles magic over copper for exclusive CO_(2)conversion to pure formic acid

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Science China Chemistry 2022年第3期65卷 421-422页

作者： Zidong Wei The State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource UtilizationSchool of Chemistry and Chemical EngineeringChongqing UniversityChongqing 400044China

CO_(2)electrolysis provides a promising solution to achieve carbon neutrality[1].With electric power from renewable energy,CO_(2)electrolysis brings considerable economic benefits by converting CO_(2)into diversified value-added chemicals,including CO,HCOOH,CH_(2),C_(2)H_(2),C_(2)H_(5)OH,and C_(3)H_(7)OH[2].Considering the profit of electrons per mole,HCOOH is one of the most desired products[3].

关键词： alloying copper desired

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Tunable Unsymmetrical Chiral N-Heterocyclic Carbene Ligands for Highly Diastereo-and Enantioselective copper-Catalyzed Tandem Borylative Cyclization:Ligand Controlled Diastereoselectivity Reversal

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CCS Chemistry 2023年第9期5卷 2088-2100页

作者： Jiahong Han Yan-Mei He Yixiao Pan Faju Li Dongyu Li Wei Hao Qing-Hua Fan Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

A distinct class of C1-symmetric N-heterocyclic carbene(NHC)ligands possessing a chiral fused tetrahydroquinoline ring and a chiral N-arylmethyl group was designed and synthesized via an asymmetric catalytic synthesis strategy.Their copper(I)complexes were successfully applied to asymmetric borylation/cyclization tandem reactions,providing facile access to a broad range of chiral borylated 2,3-trans-3,4-cis-trisubstituted tetrahydroquinolines,which are synthetically important and otherwise difficult to access,in high yields with excellent enantioselectivities and diastereoselectivities.The single-crystal X-ray diffraction analyses of the Cu(I)complexes of L3 and L6 indicate that a crowded chiral pocket around the Cu(I)-metal center is created that is beneficial for the chiral induction in this asymmetric tandemreaction.In addition,chiral all-cis 2,3,4-trisubstituted tetrahydroquinolines were also prepared by using a less bulky C2-symmetric chiral NHC ligand.A plausible catalytic cycle and transition states were proposed to account for the observed diastereoselectivity reversal.

关键词： N-heterocycliccarbenes asymmetricca-talysis boron copper tandemreaction tetrahy-droquinolines

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Influence of cadmium and copper mixtures to rhizosphere bacterial communities

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Soil Ecology Letters 2023年第1期5卷 94-107页

作者： Qirui An Yunyang Li Na Zheng Jincai Ma Shengnan Hou Siyu Sun Sujing Wang Pengyang Li Xiaoqian Li Chunmei Zhao Key Laboratory of Groundwater Resources and Environment of the Ministry of Education College of Environment and ResourcesJilin UniversityChangchun 130021China Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology Sun Yat-sen UniversityGuangzhou 510006China

To study the effects of combined Cd and Cu pollution on rhizosphere bacterial community.High-throughput sequencing was used to examine the response of rhizosphere bacterial communities to heavy-metal stress under single and mixed pollution of cadmium(Cd)and copper(Cu).With additions of Cd and Cu,the mean diversity index of rhizosphere bacterial community was in the order Cu alone>Cd-Cu mixtures>Cd alone.In all Cd and Cu treatments,the dominant phyla were Proteobacteria,Actinobacteria,Chloroflexi and Acidobacteria.In the additions with different concentrations of Cd-Cu mixtures,LEfSe indicated that there were differences in the predominant species of rhizosphere bacterial communities.Some genera such as Streptomyces and Microbacterium belonging to Actinobacteria as biomarkers were significantly enriched in both control and treatments,while some genera such as Pseudoxanthomonas and Rhodopseudomonas belonging to Proteobacteria as biomarkers were observed to be enriched in the additions with single and mixture of Cd and Cu.According to the Nonmetric multidimensional scaling(NMDS)analysis,the structure of rhizosphere bacterial community was different between treatments and the CK.Principal Component Analysis(PCA)and permutational multivariate analysis of variance(PERMANOVA)showed that there were significant differences among treatments(p<0.01),and that the addition of Cu might be the primary factor affecting the composition of rhizosphere bacterial communities.

关键词： Cadmium copper High-throughput sequencing Bacterial community structure

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Generation of micro/nano hybrid surface structures on copper by femtosecond pulsed laser irradiation

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Nanomanufacturing and Metrology 2022年第3期5卷 274-282页

作者： Ayumi Nakajima Masaki Omiya Jiwang Yan School of Integrated Design Engineering Graduate School of Science and TechnologyKeio UniversityYokohama 223-8522Japan Department of Mechanical Engineering School of Science and TechnologyKeio UniversityYokohama 223-8522Japan

The delamination of copper lead frames from epoxy molding compounds(EMC)is a severe problem for microelectronic devices,as it leads to reduced heat dissipation or circuit breakage.The micro/nanoscale surface structuring of copper is a promising method to improve the copper-EMC interfacial adhesion.In this study,the generation of micro/nano hybrid structures on copper surfaces through femtosecond pulsed laser irradiation is proposed to improve interfacial adhesion.The micro/nano hybrid structures were realized by generating nanoscale laser-induced periodic surface structures(LIPSS)on microscale parallel grooves.Several types of hybrid surface structures were generated by changing the laser polarization direction,fluence,and scanning speed.At a specific aspect ratio of microgrooves,a latticed structure was generated on the sides of microgrooves by combining LIPSS formation and direct laser interference patterning.This study provides an efficient method for the micro/nanoscale hybrid surface structure formation for interfacial adhesion improvement between copperand EMC.

关键词： Femtosecond pulsed laser copper Metal surface LIPSS Direct laser interference patterning-Micro/nano hybrid structures

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