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Light People:*** May Lau,newly elected US NAE member in Hong Kong,talks about future of photonics and women in science

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Light(Science & Applications) 2024年第4期13卷 602-608页

作者： Yating wan chenzi Guo Electrical and computer Engineering the ComputerElectrical and Mathematical Sciences and Engineering DivisionKing Abdullah University of Science and Technology23955-6900 ThuwalSaudi Arabia changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina

Editorial Photonics technology remains a driving force in today’s scientific landscape,marked by continuous innovation and crossdisciplinary *** an enlighting conversation with Light:Science&Applications,*** May Lau,a pioneer in photonics research,shares her deep insights on the evolution of technologies of LEDs,lasers,challenges of hetero-epitaxy,and the future of micro-LEDs and quantum dot *** honored as a member of the US National Academy of Engineering(NAE)for her significant contributions to photonics and electronics using III-V semiconductors on silicon,*** stands out as the sole Hong Kong scholar inducted into the NAE this year,joining 114 new and 21 international *** this exclusive Light People interview,*** shares her journey as a pioneering woman in engineering,her commitment to mentorship and academia,and her perspective on advancing female representation in *** summary provided is distilled from ***’s thoughtful responses during the *** a deeper exploration of ***’s experiences and advice,the full interview is available in the Supplementary material.

关键词： interview lighting driving

Modified constitutive models for Inconel 718 considering current density and temperature in electrically assisted forming process

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chinese journal of Aeronautics 2024年第2期37卷 524-540页

作者： Xuan cUI Rui ZHAO Min wan School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China jiangxi Research Institute of Beihang University Jiangxi 330000China

Electrically Assisted Forming(EAF)technology has obvious advantages in material *** develop an effective constitutive model considering electrical effects,room temperature and electrically assisted quasi-static uniaxial tensile tests were conducted using ultrathin nickelbased superalloy plates with a thickness of 0.25 *** research focused on the two most widely recognized effects:the joule thermal and the electric athermal *** mechanism of current action can be divided into two scenarios:one considering the joule thermal effect only,and the other considering both effects *** basic constitutive models,namely the Modified-Hollomon model and the johnson-cook(j-c)model,were selected to be optimized through the classification of two different situations,and four optimized constitutive models were *** was found that the j-c model with simultaneous consideration of the joule thermal effect and electric athermal effect had the best prediction effect by comparing the results of these four ***,the accuracy of the optimization model was verified by finite element simulation of the electrically assisted stretching optimization *** results show that the constitutive model can effectively predict the temperature effect caused by the joule heat effect and the athermal effect of current on the material.

关键词： joule heating Elastoplasticity Plastic deformation Superalloys constitutive models

Topological magnetoelectric response in ferromagnetic axion insulators

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National Science Review 2024年第2期11卷 8-14页

作者： Yuhao wan jiayu Li Qihang Liu Department of Physics and Shenzhen Institute for Quantum Science and Engineering(SIQSE) Southern University of Science and Technology Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices Southern University of Science and Technology Guangdong Provincial Key Laboratory for computational Science and Material Design Southern University of Science and Technology

The topological magnetoelectric effect （TME） is a hallmark response of the topological field theory,which provides a paradigm shift in the study of emergent topological ***,its direct observation is yet to be realized due to the demanding magnetic configuration required to gap all surface ***,we theoretically propose that axion insulators with a simple ferromagnetic configuration,such as the MnBi2Te4/（Bi2Te3）nfamily,provide an ideal playground to realize the *** the designed triangular prism geometry,all the surface states are magnetically *** a vertical electric field,the surface Hall currents give rise to a nearly half-quantized orbital moment,accompanied by a gapless chiral hinge mode circulating in ***,the orbital magnetization from the two topological origins can be easily distinguished by reversing the electric *** work paves the way for direct observation of the TME in realistic axion-insulator materials.

关键词： topological magnetoelectric effect axion insulator magnetic topological materials

Intravascular photoacoustic and optical coherence tomography imaging dual-mode system for detecting spontaneous coronary artery dissection: A feasibility study

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journal of Innovative Optical Health Sciences 2024年第1期17卷 77-86页

作者： Yongwei wang Yuyang wan Zhongjiang chen MOE Key Laboratory of Laser Life Science&Institute of Laser Life Science South China Normal University Guangzhou 510631P.R.China college of Biophotonics South china Normal University Guangzhou 510631 P.R.China School of Medical Technology and Engineering Fujian Medical University Fuzhou 350004 P.R.China

In this work,we present an intravascular dual-mode endoscopic system capable of both intravascular photoacoustic imaging(IVPAI)and intravascular optical coherence tomography(IVOcT)for recognizing spontaneous coronary artery dissection(ScAD)*** provides high-resolution and high-penetration images of intramural hematoma(IMH)at different depths,so it is especially useful for imaging deep blood clots associated with imaging *** can readily visualize the double-lumen morphology of blood vessel walls to identify intimal *** also demonstrate the capability of this dual-mode endoscopic system using mimicking phantoms and biological samples of blood clots in ex vivo porcine *** results of the experiments indicate that the combined IVPAI and IVOcT technique has the potential to provide a more accurate ScAD assessment method for clinical applications.

关键词： Spontaneous coronary artery dissection(ScAD) intravascular optical coherence tomography(IVOcT) intravascular photoacoustic imaging(IVPAI)

A Reliable Iteration Algorithm for One-Bit compressive Sensing on the Unit Sphere

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 801-822页

作者： Yan-cheng LU Ning BI An-hua wan School of Mathematics Sun Yat-sen UniversityGuangzhou 510275China

The one-bit compressed sensing problem is of fundamental importance in many areas,such as wireless communication,statistics,and so ***,the optimization of one-bit problem coustrained on the unit sphere lacks an algorithm with rigorous mathematical proof of convergence and *** this paper,an iteration algorithm is established based on difference-of-convex algorithm for the one-bit compressed sensing problem constrained on the unit sphere,with iterating formula■,where c is the convex cone generated by the one-bit measurements andη_(1)>η_(2)>1/*** new algorithm is proved to converge as long as the initial point is on the unit sphere and accords with the measurements,and the convergence to the global minimum point of the l_(1)norm is discussed.

关键词： one-bit compressed sensing difference of convex algorithm iteration algorithm ■1-minimization

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cobalt-catalyzed reductive alkynylation to construct c(sp)-c(sp^(3))and c(sp)-c(sp^(2))bonds

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chinese chemical Letters 2024年第7期35卷 253-258页

作者： Lei wan Yizhou Tong Xi Lu Yao Fu Hefei National Research center for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Precision and Intelligent chemistry School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

Transition-metal-catalyzed cross-electrophile coupling has emerged as a reliable method for constructing carbon–carbon ***,we report a general method,cobalt-catalyzed reductive alkynylation,to construct c(sp)-c(sp^(3))and c(sp)-c(sp^(2))*** presented reaction has a broad substrate scope,enabling the efficient cross-electrophile coupling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)*** presented reaction is conducted under mild conditions,tolerating many functional groups,thus suitable for the modification and synthesis of biologically active molecules.

关键词： cobalt-catalysis cross-electrophile coupling carbon-carbon bond formation Reductive alkynylation Alkyne synthesis

Recent Advances in Mechanistic Understanding of Metal-Free carbon Thermocatalysis and Electrocatalysis with Model Molecules

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Nano-Micro Letters 2024年第7期16卷 74-97页

作者： Wei Guo Linhui Yu Ling Tang Yan wan Yangming Lin cAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021People’s Republic of China State Key Laboratory of Structural chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Institute of Urban Environment Chinese Academy of SciencesXiamen 361021People’s Republic of China

Metal-free carbon,as the most representative heterogeneous metal-free catalysts,have received considerable interests in electro-and thermo-catalytic reac-tions due to their impressive performance and *** the past decade,well-designed carbon catalysts with tunable structures and heteroatom groups coupled with various characterization techniques have proposed numerous reaction ***,active sites,key intermediate species,precise structure-activity relationships and dynamic evolution processes of carbon catalysts are still rife with controversies due to the monotony and limitation of used experimental *** this Review,we sum-marize the extensive efforts on model catalysts since the 2000s,particularly in the past decade,to overcome the influences of material and structure limitations in metal-free carbon *** both nanomolecule model and bulk model,the real contribution of each alien species,defect and edge configuration to a series of fundamentally important reactions,such as thermocatalytic reactions,electrocatalytic reactions,were systematically *** with in situ techniques,isotope labeling and size control,the detailed reaction mechanisms,the precise 2D structure-activity relationships and the rate-determining steps were revealed at a molecular ***,the outlook of model carbon catalysis has also been proposed in this work.

关键词： Metal-free carbon catalysts Model catalyst Electrocatalysis Active site Reaction mechanisms

Identification of the optimal doping position of hetero-atoms in chalcogen-doped Fe-N-c catalysts for oxygen reduction reaction

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Particuology 2024年第6期89卷 99-108页

作者： Weihao Liu Huanhuan He Qingtao Liu Xin wan jianglan Shui School of Materials Science and Engineering Beihang UniversityBeijing100191China School of Space and Environment Beihang UniversityBeijing102206China Tianmushan Laboratory Hangzhou310023China

The excellent oxygen reduction reaction(ORR)activity of Fe–N–c catalysts in acidic media makes them potential for low-cost proton exchange membrane fuel *** recent years,it has been shown that heteroatoms(B,O,S,P,cl,F,etc.)can be used as electron-withdrawing groups to modulate the planar structure and electron distribution of the Fe–Nx active sites to achieve simultaneous improvement of catalytic activity and ***,the optimal location of the heteroatoms remains ***,taking chalcogen heteroatoms(S and Se)as an example,we control the doping positions and investigate their effect on the ORR performance of the Fe–N–c *** first coordination shell of the iron single atom is identified as the optimal doping *** optimized catalysts Fe–N_(3)Se_(1)/Nc and Fe–N_(3)Se_(1)/Nc demonstrate improved activity and stability in both half cells and fuel *** work provides insights into the enhancement mechanism of heteroatom doping in single-atom catalysts.

关键词： Oxygen reduction reaction Fe-N-c catalysts Hetero-atom doping Doping position Enhancement mechanism

copper catalyzed Enantioconvergent Nucleophilic Substitutions

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chinese journal of chemistry 2024年第10期42卷 1161-1174页

作者： chunxi Huang Zilong wan Aoping Zhu caiyou chen college of chemistry and Molecular Sciences Wuhan UniversityWuhanHubei 430072China Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules and college of chemistry and chemical Engineering Hubei UniversityWuhanHubei 430062China

As a versatile earth-abundant transition metal,cu has long been widely applied in the c—c and c—X bond forming *** for now,low-valent cu(Ⅰ)is known to reduce the redox active electrophiles via an SET pathway to give the corresponding radical and cu(Ⅱ)*** resulting cu(Ⅱ)species can interact with the radical via the out-sphere pathway,affording the coupling ***,cu(Ⅱ)can trap the radical through the inner-sphere process to generate cu(Ⅲ)species and then realize challenging bond formations due to the facile reductive elimination of cu(Ⅲ)*** copper catalysis has been widely applied in arylations of various nucleophiles,copper-catalyzed enantioconvergent nucleophilic substitutions of racemic alkyl electrophiles have been less explored,likely due to the difficulties in overcoming the reduction potential of alkyl electrophiles,elimination of side reactions,and enantiomeric *** order to overcome the high reduction potential of alkyl electrophiles,the photo-induced strategy has been developed under mild *** alternative strategy with new anionic tridentate ligands has also been reported in this *** review summarizes recent developments in copper-catalyzed enantioconvergent nucleophilic substitutions of alkyl electrophiles by various nucleophiles to realize c—N,c—c,c—B,c—P and c—O bond formations and their brief mechanistic studies.

关键词： Enantioconvergent Nucleophilic substitution copper Radical reactions Photocatalysis Asymmetric catalysis