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Opto-Electronic Advances 2024年第3期7卷 26-34页

作者： Yahui Liu Shunda Qiao Chao Fang Ying He Haiyue Sun Jian Liu Yufei Ma National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of TechnologyHarbin 150000China Zhengzhou research Institute Harbin Institute of TechnologyZhengzhou 450000China advanced Microscopy and Instrumentation research center School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China.

A highly sensitive light-induced thermoelectric spectroscopy(LITES)sensor based on a multi-pass cell(MPC)with dense spot pattern and a novel quartz tuning fork(QTF)with low resonance frequency is reported in this *** erbi-um-doped fiber amplifier(EDFA)was employed to amplify the output optical power so that the signal level was further *** optical path length(OPL)and the ratio of optical path length to volume(RLV)of the MPC is 37.7 m and 13.8 cm^(-2),respectively.A commercial QTF and a self-designed trapezoidal-tip QTF with low frequency of 9461.83 Hz were used as the detectors of the sensor,*** target gas selected to test the performance of the system was acetylene(C2H2).When the optical power was constant at 1000 mW,the minimum detection limit(MDL)of the C2H2-LITES sensor can be achieved 48.3 ppb when using the commercial QTF and 24.6 ppb when using the trapezoid-al-tip *** improvement of the detection performance by a factor of 1.96 was achieved after replacing the commer-cial QTF with the trapezoidal-tip QTF.

关键词： light-induced thermoelectric spectroscopy quartz tuning fork multi-pass cell gas sensing

Two-dimensional semiconductor transistors and integrated circuits for advanced technology nodes

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National Science Review 2024年第03期11卷 11-13页

作者： Weisheng Li Haoliang Shen Hao Qiu Yi Shi Xinran Wang National Laboratory of Solid-State Microstructures School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced Microstructures Nanjing University Suzhou Laboratory The Interdisciplinary research center for Future Intelligent Chips(Chip-X) Nanjing University School of Integrated Circuits Nanjing University

Two-dimensional(2D) semiconductors,particularly transition metal dichalcogenides, exhibit high mobility within atomic-scale thickness, immunity to short-channel effects, and back-end-of-the-line(BEOL) compatibility wi...

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Supermassive black holes triggered by QCD axion bubbles

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Communications in Theoretical Physics 2024年第5期76卷 134-139页

作者： Hai-Jun Li Ying-Quan Peng Wei Chao Yu-Feng Zhou Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China center for advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing/HangzhouChina

Supermassive black holes(SMBHs)are ubiquitous in the center of galaxies,although the origin of their massive seeds is still *** this paper,we investigate the formation of SMBHs from the quantum chromodynamics(QCD)axion *** this case,primordial black holes(PBHs)are considered as the seeds of SMBHs,which are generated from the QCD axion bubbles due to an explicit Peccei–Quinn(PQ)symmetry breaking after *** QCD axion bubbles are formed when the QCD axion starts to oscillate during the QCD phase *** consider a general case in which the axion bubbles are formed with the bubble effective angle θ_(eff)∈(0,π],leading to the minimum PBH mass∼■(10^(4)−10^(7))M⊙for the axion decay constant f_(a)∼■(10^(16))*** PBHs at this mass region may account for the seeds of SMBHs.

关键词： supermassive black holes primordial black holes quantum chromodynamics axion

Nickel-Catalyzed Regiodivergent Acylzincation of Styrenes with Organozincs and CO

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Chinese Journal of Chemistry 2024年第6期42卷 599-604页

作者： Chenglong Wang Ning Liu Xianqing Wu Jingping Qu Yifeng Chen Key Laboratory for advanced Materials and Joint International research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237 China Dedicated to the Special Issue of C1 Chemistry.

Transition metal-catalyzed carbometallation of unsaturated hydrocarbons constitutes one of the most efficient synthetic methodologies for the construction of C—C ***,the incorporation of organometallic reagent with the CO gas as a nucleophilic acyl synthon could enable the acylmetallation reaction,which greatly increases the horizon of carbometallation ***,we report a nickel-catalyzed regiodivergent acylzincation of o-cyano cinnamate ester and o-cyano styrene,in which the cyano moiety intramolecularly captures zinc intermediates to trigger the tandem cyclization *** protocol features mild conditions,broad substrate scope and excellent functional group tolerance,thus affording a diverse array of highly functionalized carbocyclic compounds.

关键词： Carbonylation Carbometallation Styrene Nickel Cyclization

Microstructures and micromechanical behaviors of high -entropy alloys investigated by synchrotron X-ray and neutron diffraction techniques: A review

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1333-1349页

作者： Yubo Huang Ning Xu Huaile Lu Yang Ren Shilei Li Yandong Wang Beijing advanced Innovation center of Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China AnSteel Beijing research Institute Co.Ltd. Beijing 102200China Spallation Neutron Source Science center Dongguan 523803China Department of Physics City University of Hong KongHong Kong 999077China Institute for Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

High-entropy alloys(HEAs)possess outstanding features such as corrosion resistance,irradiation resistance,and good mechan-ical properties.A few HEAs have found applications in the fields of aerospace and *** studies on the deformation mech-anisms of HEAs can guide microstructure control and toughness design,which is vital for understanding and studying state-of-the-art structural *** X-ray and neutron diffraction are necessary techniques for materials science research,especially for in situ coupling of physical/chemical fields and for resolving macro/microcrystallographic information on ***,several re-searchers have applied synchrotron X-ray and neutron diffraction methods to study the deformation mechanisms,phase transformations,stress behaviors,and in situ processes of HEAs,such as variable-temperature,high-pressure,and hydrogenation *** this review,the principles and development of synchrotron X-ray and neutron diffraction are presented,and their applications in the deformation mechanisms of HEAs are *** factors that influence the deformation mechanisms of HEAs are also *** review fo-cuses on the microstructures and micromechanical behaviors during tension/compression or creep/fatigue deformation and the application of synchrotron X-ray and neutron diffraction methods to the characterization of dislocations,stacking faults,twins,phases,and intergrain/interphase stress *** on future developments of synchrotron X-ray and neutron diffraction and on research directions on the deformation mechanisms of novel metals are discussed.

关键词： high-entropy alloys microstructures micromechanical behaviors synchrotron X-ray diffraction neutron diffraction

Recent progress on Sn_(3)O_(4)nanomaterials for photocatalytic applications

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 231-244页

作者： Xin Yu Congcong Li Jian Zhang Lili Zhao Jinbo Pang Longhua Ding Institute for advanced Interdisciplinary research(iAIR) School of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China School of Sino-German Engineering Shanghai Technical Institute of Electronics and InformationShanghai 201411China Division of Systems and Synthetic Biology Department of Life SciencesChalmers University of Technology41296 GöteborgSweden

Tin(IV)oxide(Sn_(3)O_(4))is layered tin and exhibits mixed valence *** has emerged as a highly promising visible-light pho-tocatalyst,attracting considerable *** comprehensive review is aimed at providing a detailed overview of the latest advance-ments in research,applications,advantages,and challenges associated with Sn_(3)O_(4)photocatalytic *** fundamental con-cepts and principles of Sn_(3)O_(4)are ***_(3)O_(4)possesses a unique crystal structure and optoelectronic properties that allow it to ab-sorb visible light efficiently and generate photoexcited charge carriers that drive photocatalytic ***,strategies for the control and improved performance of Sn_(3)O_(4)photocatalytic nanomaterials are *** control,ion doping,and hetero-structure construction are widely employed in the optimization of the photocatalytic performance of Sn_(3)O_(4)*** effective imple-mentation of these strategies improves the photocatalytic activity and stability of Sn_(3)O_(4)***,the review explores the diverse applications of Sn_(3)O_(4)photocatalytic nanomaterials in various fields,such as photocatalytic degradation,photocatalytic hydro-gen production,photocatalytic reduction of carbon dioxide,solar cells,photocatalytic sterilization,and optoelectronic *** discus-sion focuses on the potential of Sn_(3)O_(4)-based nanomaterials in these applications,highlighting their unique attributes and ***,the review provides an outlook on the future development directions in the field and offers guidance for the exploration and de-velopment of novel and efficient Sn_(3)O_(4)-based *** the identification of emerging research areas and potential avenues for improvement,this review aims to stimulate further advancements in Sn_(3)O_(4)-based photocatalysis and facilitate the translation of this promising technology into practical applications.

关键词： photocatalysis Sn_(3)O_(4)nanomaterials building heterostructures antibacterial therapy water splitting

Geometrical transition properties of vortex cavitation and associated flow-choking characteristics in poppet valves

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期25卷 455-469页

作者： Liang LU Zhongdong LIANG Yuming LIU Zhipeng WANG Shohei RYU School of Mechanical Engineering Tongji UniversityShanghai 201804China Frontiers Science center for Intelligent Autonomous Systems Tongji UniversityShanghai 201210China technical research Laboratory Hitachi Construction Machinery Co.Ltd.Tsuchiura 300-0013Japan

Poppet valves have become increasingly significant in ensuring precise digital flow rate and pressure control in hydraulic systems,necessitating a more profound understanding of the geometrical properties of cavitation in them,as well as associated flow-choking *** a comparative analysis with experimentally observed cavity images,we found that large eddy simulation(LES)turbulence modeling effectively replicates the geometrical properties of cavitation in these *** analysis demonstrated that cavitation is generated from vortices that result from the interaction between the notch contracta flow and the surrounding fluid *** in the internal or external vena contracta conditions result in fixed or discrete cavities,and the length-to-diameter ratio serves as a measure of the transition between internal and external vena contracta flow *** study establishes a threshold length-to-diameter ratio of approximately 2 for the tested poppet *** specifically,in notch structures with a smaller valve opening,longer sealing length,and smaller throttling angle(corresponding to a larger length-to-diameter ratio),the liquid-to-vapor transfer process is more evident than that in the reverse direction.A long-standing vapor cavity becomes fixed inside the notch,leading to a more pronounced flow-choking *** contrast,for structures with a smaller length-to-diameter ratio,the cavitation process for discrete vapor cavities is more complete,ensuring fluid flow continuity and significantly reducing the occurrence of the flow-choking phenomenon.

关键词： Poppet valves Vena contracta Vortex flow Vapor cavity Flow-choking

Cyclic Pulsating Pressure Enhanced Segregating Structuration of Ultra-High Molecular Weight Polyethylene/Graphene Composites as High-performance Light-Weight EMI Shields

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Chinese Journal of Polymer Science 2024年第7期42卷 958-967,I0008页

作者： Yun-Zhi Huang Xiao-Xiao Liu Lan-Wei Li Guang-Ming Huang Zhao-Xia Huang Jin-Ping Qu National Engineering research center of Novel Equipment for Polymer Processing Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced ManufacturingSchool of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou 510641China School of advanced Manufacturing Technology Guangdong Mechanical&Electrical PolytechnicGuangzhou 510550China

Currently,the enhancement in electromagnetic interference(EMI)performance of polymeric composite generally relies on either improving electrical conductivity(σ)for stronger electromagnetic(EM)reflections or tailoring structure for higher EM ***,we proposed a novel technique called cyclic pulsating pressure enhanced segregating structuration(CPP-SS),which can reinforce these two factors *** structural information was supplied by optical microscopy(OM)and scanning electron microscopy(SEM),both of which confirmed the formation and evolution of segregate structured ultra-high molecular weight polyethylene(UHMWPE)/graphene ***,the result showed that CPP-SS can significantly improve theσof ***,advanced specific EMI shielding efficiency of 31.1 d B/mm was achieved for UHMWPE/graphene composite at 1-mm thickness and a low graphene loading of 5 wt%.Meanwhile,it also confirmed that the intrinsic disadvantage of poor mechanical properties of conventional segregated structure composites can be *** work is believed to provide a fundamental understanding of the structural and performance evolutions of segregated structured composites prepared under CPPSS,and to bring us a simple and efficient approach for fabricating high-performance,strong and light-weight polymeric EMI shields.

关键词： Cyclic pulsating pressure Segregated structure Ultra-high molecular weight polyethylene Graphene Electromagnetic interface

Steric hindrance modulation of hexaazatribenzanthraquinone isomers for high-capacity and wide-temperature-range aqueous proton battery

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National Science Review 2024年第4期11卷 271-282页

作者： Mingsheng Yang Yuxin Hao Bei Wang Yan Wang Liping Zheng Rui Li Huige Ma Xinyu Wang Xiaoming Jing Hongwei Li Mengxiao Li Zhihui Wang Yujie Dai Guangcun Shan Mingjun Hu Jun Luo Jun Yang School of Materials Science and Engineering Beihang University Beijing Institute of Nanoenergy &Nanosystems Chinese Academy of Sciences center on Nanoenergy research School of Physical Science & TechnologyGuangxi University School of Chemistry and Chemical Engineering Center on Nanoenergy Research Guangxi University School of Instrumentation Science and Opto-electronics Engineering Beihang University ShenSi Lab Shenzhen Institute for Advanced StudyUniversity of Electronic Science and Technology of China

Organic materials with rich active sites are good candidates of high-capacity anodes in aqueous batteries,but commonly low utilization of active sites limits their ***,two isomers,symmetric and asymmetric hexaazatribenzanthraquinone（s-HATBAQ and a-HATBAQ）,with rich active sites have been synthesized in a controllable *** has been revealed for the first time that a sulfuric acid catalyst can facilitate the stereoselective formation of *** to the reduced steric hindrance in favor of proton insertion as well as the amorphous structure conducive to electrochemical dynamics,s-HATBAQ exhibits 1.5 times larger specific capacity than ***,the electrode of s-HATBAQ with50% reduced graphene oxide（s-HATBAQ-50%rGO） delivers a record high specific capacity of405 mAh g-1in ***,the assembled MnO2//s-HATBAQ-50%rGO aqueous proton full batteries show an exceptional cycling stability at 25℃ and can maintain ～92% capacity after1000 cycles at 0.5 A g-1at-80℃.This work demonstrates the controllable synthesis of isomers,showcases a wide-temperature-range prototype proton battery and highlights the significance of precise mole cular structure modulation in organic energy storage.

关键词： stereoisomers steric effect aqueous battery super cycling stability ultra-low temperature proton battery

A Magnetic-Driven Multi-motion Robot with Position/Orientation Sensing Capability

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research 2024年第1期2023卷 675-685页

作者： Liwen Zhang Song Zhao Xinzhao Zhou Xueshan Jing Yu Zhou Yan Wang Yantong Zhu Xiaolin Liu Zehui Zhao Deyuan Zhang Lin Feng Huawei Chen School of Mechanical Engineering and Automation Beihang UniversityBeijingChina Beijing advanced Innovation center for Biomedical Engineering Beihang UniversityBeijingChina

Miniature magnetic-driven robots with multimode motions and high-precision pose sensing capacity(position and orientation)are greatly demanded in in situ manipulation in narrow opaque enclosed *** magnetic robots have been carried out,whereas their deformations normally remain in single mode,and the lack of the robot’s real-time status leads to its beyond-sight remagnetization and manipulation being *** function integration of pose sensing and multimode motion is still of ***,a multimotion thin-film robot is created in a novel multilayer structure with a magneticdriven layer covered by a heating-sensing conductive *** a heating-sensing layer not only can segmentally and on-demand heat the magnetic-driven layer for in situ magnetization reprogramming and multimode motions but also can precisely detect the robot’s pose(position and orientation)from its electrical-resistance effect by creating a small deformation under preset magnetic fields.

关键词： robot Robot motion