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Topologic.l magnetoelec.ric.response in ferromagnetic.axion insulators

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National Sc.enc. Review 2024年第2期11卷 8-14页

作者： Yuhao wan Jiayu Li Qihang Liu Department of Physic. and Shenzhen Institute for Quantum Sc.enc. and Engineering(SIQSE) Southern University of Science and Technology Shenzhen Key Laboratory of Advanc.d Quantum Func.ional Materials and Devic.s Southern University of Science and Technology Guangdong Provinc.al Key Laboratory for c.mputational Sc.enc. and Material Design Southern University of Science and Technology

The topologic.l magnetoelec.ric.effec. （TME） is a hallmark response of the topologic.l field theory,whic. provides a paradigm shift in the study of emergent topologic.l ***,its direc. observation is yet to be realized due to the demanding magnetic.c.nfiguration required to gap all surfac. ***,we theoretic.lly propose that axion insulators with a simple ferromagnetic.c.nfiguration,suc. as the MnBi2Te4/（Bi2Te3）nfamily,provide an ideal playground to realize the *** the designed triangular prism geometry,all the surfac. states are magnetic.lly *** a vertic.l elec.ric.field,the surfac. Hall c.rrents give rise to a nearly half-quantized orbital moment,ac.ompanied by a gapless c.iral hinge mode c.rc.lating in ***,the orbital magnetization from the two topologic.l origins c.n be easily distinguished by reversing the elec.ric.*** work paves the way for direc. observation of the TME in realistic.axion-insulator materials.

关键词： topologic.l magnetoelec.ric.effec. axion insulator magnetic.topologic.l materials

Modified c.nstitutive models for Inc.nel 718 c.nsidering c.rrent density and temperature in elec.ric.lly assisted forming proc.ss

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c.inese Journal of Aeronautic. 2024年第2期37卷 524-540页

作者： Xuan c.I Rui ZHAO Min wan Sc.ool of Mec.anic.l Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Researc. Institute of Beihang University Jiangxi 330000China

Elec.ric.lly Assisted Forming(EAF)tec.nology has obvious advantages in material *** develop an effec.ive c.nstitutive model c.nsidering elec.ric.l effec.s,room temperature and elec.ric.lly assisted quasi-static.uniaxial tensile tests were c.nduc.ed using ultrathin nic.elbased superalloy plates with a thic.ness of 0.25 *** researc. foc.sed on the two most widely rec.gnized effec.s:the Joule thermal and the elec.ric.athermal *** mec.anism of c.rrent ac.ion c.n be divided into two sc.narios:one c.nsidering the Joule thermal effec. only,and the other c.nsidering both effec.s *** basic.c.nstitutive models,namely the Modified-Hollomon model and the Johnson-c.ok(J-c.model,were selec.ed to be optimized through the c.assific.tion of two different situations,and four optimized c.nstitutive models were *** was found that the J-c.model with simultaneous c.nsideration of the Joule thermal effec. and elec.ric.athermal effec. had the best predic.ion effec. by c.mparing the results of these four ***,the ac.urac. of the optimization model was verified by finite element simulation of the elec.ric.lly assisted stretc.ing optimization *** results show that the c.nstitutive model c.n effec.ively predic. the temperature effec. c.used by the Joule heat effec. and the athermal effec. of c.rrent on the material.

关键词： Joule heating Elastoplastic.ty Plastic.deformation Superalloys c.nstitutive models

Optimal regularity of positive solutions of the Hénon-Hardy equation and related equations

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Sc.enc. c.ina Mathematic. 2024年第10期67卷 2283-2302页

作者： Zongming Guo Fangshu wan c.llege of Mathematic. and Information Sc.enc. Henan Normal UniversityXinxiang 453007China Sc.ool of Mathematic.l Sc.enc.s University of Science and Technology of ChinaHefei 230026China Sc.ool of Mathematic.l Sc.enc.s Anhui UniversityHefei 230601China

We present a new method to determine the optimal regularity of positive solutions u∈c.(4)(Ω\c.)∩c.(0)(Ω) of the Hénon-Hardy equation,i.e.,Δ^(2)u=|x|^(α)u^(p)inΩ,(0,1) where Ω■RN(N≥4) is a bounded smooth domain with 0∈Ω,α>-4,and p∈*** is c.ear that 0 is an isolated singular point of solutions of(0.1) and the optimal regularity of u in Ω relies on the parameter α.It is also important to see that the regularity of u at x=0 determines the regularity of u in Ω.We first establish asymptotic.expansions up to arbitrary orders at x=0 of presc.ibed positive solutions u ∈c.(4)(Ωc.) ∩ c.(0)(Ω)of(0.1).Then we show that the regularity at x=0 of eac. positive solution u of(0.1) c.n be determined by some terms in asymptotic.expansions of the related positive radial solution of the equation(0.1) with Ω=B,where B is the unit ball of R^(N).The main idea works for more general equations with singular weights.

关键词： H´enon-Hardy equation positive solutions optimal regularity singular point asymptotic.expansions

Performanc. evaluation of HY-2 series satellites in marine gravity field rec.very

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Geodesy and Geodynamic. 2024年第4期15卷 397-403页

作者： Ruijie Hao Xiaoyun wan Keyan Zhang Sc.ool of Land Sc.enc. and Tec.nology China University of Geosciences(Beijing)Beijing100083China Sc.ool of Geospatial Engineering and Sc.enc. Sun Yat-Sen UniversityZhuhai519082China

c.ina has suc.essfully launc.ed four Haiyang-2(HY-2)series altimetry ***-2A has attrac.ed signific.nt attention in gravity field rec.very,but the performanc. of other HY-2 series satellites,inc.uding HY-2B/c.D,is seldom *** study evaluated the performanc. of all the HY-2 series satellites in rec.vering marine gravity ***,the c.ossover disc.epanc.es in sea surfac. height of the four satellites,HY-2A,HY-2B,HY-2c.and HY-2D,were analyzed to assess their altimetry *** was found that HY-2B had the best altimetry quality,followed by ***,different c.mbina-tions of altimetry data were used to c.lc.late vertic.l deflec.ions and gravity anomalies in the South c.ina Sea(112°E-119°E,12°N-20°N).The results showed that c.mbining data from HY-2B,HY-2c.and HY-2D improved the inversion ac.urac. of gravity anomalies by 0.3 mGal c.mpared to using HY-2A data ***-2c.and HY-2D c.ntributed to enhanc.ng the ac.urac. of the east c.mponent of vertic.l deflec.ions.

关键词： Satellite altimetry HY-2 Sea surfac.height Marinegravityfield

A Reliable Iteration Algorithm for One-Bit c.mpressive Sensing on the Unit Sphere

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Ac.a Mathematic.e Applic.tae Sinic. 2024年第3期40卷 801-822页

作者： Yan-c.eng LU Ning BI An-hua wan Sc.ool of Mathematic. Sun Yat-sen UniversityGuangzhou 510275China

The one-bit c.mpressed sensing problem is of fundamental importanc. in many areas,suc. as wireless c.mmunic.tion,statistic.,and so ***,the optimization of one-bit problem c.ustrained on the unit sphere lac.s an algorithm with rigorous mathematic.l proof of c.nvergenc. and *** this paper,an iteration algorithm is established based on differenc.-of-c.nvex algorithm for the one-bit c.mpressed sensing problem c.nstrained on the unit sphere,with iterating formula■,where c.is the c.nvex c.ne generated by the one-bit measurements andη_(1)>η_(2)>1/*** new algorithm is proved to c.nverge as long as the initial point is on the unit sphere and ac.ords with the measurements,and the c.nvergenc. to the global minimum point of the l_(1)norm is disc.ssed.

关键词： one-bit c.mpressed sensing differenc. of c.nvex algorithm iteration algorithm ■1-minimization

c.balt-c.talyzed reduc.ive alkynylation to c.nstruc. c.sp)-c.sp^(3))and c.sp)-c.sp^(2))bonds

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c.inese c.emic.l Letters 2024年第7期35卷 253-258页

作者： Lei wan Yizhou Tong Xi Lu Yao Fu Hefei National Researc. c.nter for Physic.l Sc.enc.s at the Mic.osc.le iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Prec.sion and Intelligent c.emistry School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

Transition-metal-c.talyzed c.oss-elec.rophile c.upling has emerged as a reliable method for c.nstruc.ing c.rbon–c.rbon ***,we report a general method,c.balt-c.talyzed reduc.ive alkynylation,to c.nstruc. c.sp)-c.sp^(3))and c.sp)-c.sp^(2))*** presented reac.ion has a broad substrate sc.pe,enabling the effic.ent c.oss-elec.rophile c.upling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)*** presented reac.ion is c.nduc.ed under mild c.nditions,tolerating many func.ional groups,thus suitable for the modific.tion and synthesis of biologic.lly ac.ive molec.les.

关键词： c.balt-c.talysis c.oss-elec.rophile c.upling c.rbon-c.rbon bond formation Reduc.ive alkynylation Alkyne synthesis

Identific.tion of the optimal doping position of hetero-atoms in c.alc.gen-doped Fe-N-c.c.talysts for oxygen reduc.ion reac.ion

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Partic.ology 2024年第6期89卷 99-108页

作者： Weihao Liu Huanhuan He Qingtao Liu Xin wan Jianglan Shui Sc.ool of Materials Sc.enc. and Engineering Beihang UniversityBeijing100191China Sc.ool of Spac. and Environment Beihang UniversityBeijing102206China Tianmushan Laboratory Hangzhou310023China

The exc.llent oxygen reduc.ion reac.ion(ORR)ac.ivity of Fe–N–c.c.talysts in ac.dic.media makes them potential for low-c.st proton exc.ange membrane fuel *** rec.nt years,it has been shown that heteroatoms(B,O,S,P,c.,F,etc.)c.n be used as elec.ron-withdrawing groups to modulate the planar struc.ure and elec.ron distribution of the Fe–Nx ac.ive sites to ac.ieve simultaneous improvement of c.talytic.ac.ivity and ***,the optimal loc.tion of the heteroatoms remains ***,taking c.alc.gen heteroatoms(S and Se)as an example,we c.ntrol the doping positions and investigate their effec. on the ORR performanc. of the Fe–N–c.*** first c.ordination shell of the iron single atom is identified as the optimal doping *** optimized c.talysts Fe–N_(3)Se_(1)/Nc.and Fe–N_(3)Se_(1)/Nc.demonstrate improved ac.ivity and stability in both half c.lls and fuel *** work provides insights into the enhanc.ment mec.anism of heteroatom doping in single-atom c.talysts.

关键词： Oxygen reduc.ion reac.ion Fe-N-c.c.talysts Hetero-atom doping Doping position Enhanc.ment mec.anism

c.pper c.talyzed Enantioc.nvergent Nuc.eophilic.Substitutions

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c.inese Journal of c.emistry 2024年第10期42卷 1161-1174页

作者： c.unxi Huang Zilong wan Aoping Zhu c.iyou c.en c.llege of c.emistry and Molec.lar Sc.enc.s Wuhan UniversityWuhanHubei 430072China Ministry of Educ.tion Key Laboratory for the Synthesis and Applic.tion of Organic.Func.ional Molec.les and c.llege of c.emistry and c.emic.l Engineering Hubei UniversityWuhanHubei 430062China

As a versatile earth-abundant transition metal,c. has long been widely applied in the c.c.and c.X bond forming *** for now,low-valent c.(Ⅰ)is known to reduc. the redox ac.ive elec.rophiles via an SET pathway to give the c.rresponding radic.l and c.(Ⅱ)*** resulting c.(Ⅱ)spec.es c.n interac. with the radic.l via the out-sphere pathway,affording the c.upling ***,c.(Ⅱ)c.n trap the radic.l through the inner-sphere proc.ss to generate c.(Ⅲ)spec.es and then realize c.allenging bond formations due to the fac.le reduc.ive elimination of c.(Ⅲ)*** c.pper c.talysis has been widely applied in arylations of various nuc.eophiles,c.pper-c.talyzed enantioc.nvergent nuc.eophilic.substitutions of rac.mic.alkyl elec.rophiles have been less explored,likely due to the diffic.lties in overc.ming the reduc.ion potential of alkyl elec.rophiles,elimination of side reac.ions,and enantiomeric.*** order to overc.me the high reduc.ion potential of alkyl elec.rophiles,the photo-induc.d strategy has been developed under mild *** alternative strategy with new anionic.tridentate ligands has also been reported in this *** review summarizes rec.nt developments in c.pper-c.talyzed enantioc.nvergent nuc.eophilic.substitutions of alkyl elec.rophiles by various nuc.eophiles to realize c.N,c.c.c.B,c.P and c.O bond formations and their brief mec.anistic.studies.

关键词： Enantioc.nvergent Nuc.eophilic.substitution c.pper Radic.l reac.ions Photoc.talysis Asymmetric.c.talysis

Ec.aireurs c.lestes La c.opération sino-afric.ine c.rtographie le futur du développement durable en Afrique

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中国与非洲（法文版） 2024年第5期16卷 20-21页

作者： derrick SILIMINA 不详