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合肥光源200MeV直线加速器束流流强测量系统的改进

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核技术 2000年第7期23卷 491-495页

作者：王贵诚李辉田宝瑛孙葆根方志高冷用斌中国科学技术大学国家同步辐射实验室合肥230029

用PC机经扩展机箱完成对8路束流信号的采集、处理；并可同时显示、打印全部8路束流流强信号于一幅，也可任选其中一路做单幅放大显示。此设备提高了直线加速器束流流强信号的测量精度，并方便了直线加速器调机人员的操作。

关键词：直线加速器束流流强数据采集测量系统

Reversible data hiding using a transformer predictor and an adaptive embedding strategy

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Frontiers of Information Technology & Electronic Engineering 2023年第8期24卷 1143-1155页

作者： Linna ZHOU zhigao LU Weike YOU Xiaofei fang School of Cyberspace Security Beijing University of Posts and TelecommunicationsBeijing100084China School of Information Science&Technology University of International RelationsBeijing100091China

In the field of reversible data hiding(RDH),designing a high-precision predictor to reduce the embedding distortion and developing an effective embedding strategy to minimize the distortion caused by embedding information are the two most critical *** this paper,we propose a new RDH method,including a predictor based on a transformer and a novel embedding strategy with multiple embedding *** the predictor part,we first design a transformer-based ***,we propose an image division method to divide the image into four parts,which can use more pixels as *** with other predictors,the transformer-based predictor can extend the range of pixels for prediction from neighboring pixels to global ones,making it more accurate in reducing the embedding *** the embedding strategy part,we first propose a complexity measurement with pixels in the target ***,we develop an improved prediction error ordering ***,we provide an embedding strategy including multiple embedding rules for the first *** proposed RDH method can effectively reduce the distortion and provide satisfactory results in improving the visual quality of data-hidden images,and experimental results show that the performance of our RDH method is leading the field.

关键词： Reversible data hiding Transformer Adaptive embedding strategy

Evolution of Weyl nodes in Ni-doped thallium niobate pyrochlore Tl_(2-x)Ni_(x)Nb_(2)O_(7)

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Science China(Physics,Mechanics & Astronomy) 2022年第9期65卷 104-111页

作者： Yuefang Hu Changming Yue Danwen Yuan Jiacheng Gao zhigao Huang Zhong fang Chen fang Hongming Weng Wei Zhang Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials College of Physics and EnergyFujian Normal UniversityFuzhou 350117China Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering Fuzhou 350117China Department of Physics University of FribourgFribourg 1700Switzerland Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

The magnetic Weyl semimetal(WSM)is important for fundamental physics and potential applications due to its spontaneous magnetism,robust band topology,and enhanced Berry *** possesses many unique quantum effects,including a large intrinsic anomalous Hall effect,Fermi arcs,and chiral *** this work,using ab initio calculations,we propose that Nidoped pyrochlore Tl2Nb2O7is a magnetic WSM caused by the exchange field splitting on bands around its quadratic band crossing *** exchange field tuned by Ni 3d on-site Coulomb interaction parameter U drives the evolution of Weyl nodes and the resulting topological phase *** Weyl nodes can exist at generic points in the Brillouin zone and are hard to identify exactly,their creation and annihilation,i.e.,the change in their number,chirality,and distribution,have been consistently confirmed with a combined theoretical approach,which employs parity criterion,symmetry indicator analysis,and the Wilson loop of the Wannier *** find that Weyl nodes remain in a large range of U and are close to the Fermi level,which makes the experimental observation very *** think that this method and our proposal of magnetic WSM will be useful in finding more WSMs and add to the understanding of the topological phase transition.

关键词： magnetic Weyl semimetal pyrochlore topological phase transition Chern number anomalous Hall effect

Boosting high initial coulombic efficiency of hard carbon by in-situ electrochemical presodiation

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Journal of Energy Chemistry 2023年第2期77卷 310-316,I0008页

作者： Nannan Qin Yanyan Sun Chao Hu Sainan Liu zhigao Luo Xinxin Cao Shuquan Liang Guozhao fang School of Materials Science and Engineering Central South UniversityChangsha 410083HunanChina School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina College of Chemistry Xiangtan UniversityXiangtan 411105HunanChina Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South UniversityChangsha 410083HunanChina

Hard carbon(HC)is a promising anode material for sodium ion batteries(SIBs),whereas inferior initial coulombic efficiency(ICE)severely limits its practical *** the present work,we propose an in situ electrochemical presodiation approach to improve ICE by mixing sodium biphenyl(Na-Bp)dimethoxyethane(DME)solution with DME-based ether electrolyte.A solid electrolyte interface(SEI)could be formed beforehand on the HC electrode and Na^(+)was absorbed to nanopores and graphene stacks,compensating for the sodium loss and preventing electrolyte decomposition during the initial charge and discharge *** this way,the ICE of half-cells was increased to nearly 100%and that of full-cells from 45%to 96%with energy density from 132.9 to 230.5 W h kg^(-1).Our work provides an efficient and facile method for improving ICE,which can potentially promote the practical application of HCbased materials.

关键词： Hard carbon In situ presodiation Initial coulombic efficiency Solid electrolyte interface Sodium-ion batteries

Light control of droplets on photo-induced charged surfaces

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National Science Review 2023年第1期10卷 259-267页

作者： fang Wang Meijin Liu Cong Liu Chao Huang Lidong Zhang Anyang Cui zhigao Hu Xuemin Du Institute of Biomedical and Health Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences University of Chinese Academy of Sciences Department of Chemistry and Molecular Engineering East China Normal University Technical Center for Multifunctional Magneto-Optical Spectroscopy(Shanghai) Engineering Research Center of Nanophotonics and Advanced Instrument(Ministry of Education)Department of Physics School of Physics and Electronic Science East China Normal University

The manipulation of droplets plays a vital role in fundamental research and practical applications,from chemical reactions to *** an intriguing and active format,light control of droplets,typically induced by photochemistry,photomechanics,light-induced Marangoni effects or light-induced electric fields,enables remote and contactless control with remarkable spatial and temporal ***,current light control of droplets suffers from poor performance and limited *** we develop a new superamphiphobic material that integrates the dual merits of light and electric field by rationally preparing liquid metal particles/poly(vinylidene fluoride-trifluoroethylene) polymer composites with photo-induced charge generation capability in real time,enabling light control of droplets on the basis of photo-induced dielectrophoretic *** demonstrate that this photo-induced charged surface(PICS)imparts a new paradigm for controllable droplet motion,including high average velocity(～35.9 mm s-1),unlimited distance,multimode motions(***,backward and rotation) and single-to-multiple droplet manipulation,which are otherwise unachievable in conventional *** further extend light control of droplets to robotic and bio-applications,including transporting a solid cargo in a closed tube,crossing a tiny tunnel,avoiding obstacles,sensing the changing environment via naked-eye color shift,preparing hydrogel beads,transporting living cells and reliable *** PICS not only provides insight into the development of new smart interface materials and microfluidics,but also brings new possibilities for chemical and biomedical applications.

关键词： light control droplet manipulation smart surface liquid metal ferroelectric

Reconstructing interfacial manganese deposition for durable aqueous zinc-manganese batteries

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National Science Review 2023年第10期10卷 139-150页

作者： Yida Hu Zhexuan Liu Lanyan Li Shan Guo Xuefang Xie zhigao Luo Guozhao fang Shuquan Liang School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan ProvinceCentral South University School of Science Hunan University of Technology and Business College of Physical Science and Technology Xinjiang University College of Chemistry Xiangtan University

Low-cost,high-satety,and broad-prospect aqueous zinc-manganese batteries(ZMBs) are limited by complex interracial *** solid-liquid interfacial state of the cathode dominates the Mn dissolution/deposition process of aqueous ZMBs,especially the important influence on the mass and charge transfer behavior of Zn2+and Mn2+.We proposed a quasi-eutectic electrolyte(QEE) that would stabilize the reversible behavior of interracial deposition and favorable interracial reaction kinetic of manganese-based cathodes in a long cycle process by optimizing mass and charge *** emphasize that the initial interfacial reaction energy barrier is not the main factor affecting cycling performance,and the good reaction kinetics induced by interfacial deposition during the cycling process is more conducive to the stable cycling of the battery,which has been confirmed by theoretical analysis,quartz crystal microbalance with dissipation monitoring,depth etching X-ray photon-electron spectroscopy,*** a result,the QEE electrolyte maintained a stable specific capacity of 250 mAh g-1at 0.5 A g-1after 350 cycles in zinc-manganese *** energy density retention rate of the ZMB with QEE increased by 174%compared to that of conventional aqueous ***,the multi-stacked soft-pack battery with a cathodic mass load of 54.4 mg maintained a stable specific capacity of 200 mAh g-1for 100 cycles,demonstrating its commercial *** work proves the feasibility of adapting lean-water QEE to the stable aqueous ZMBs.

关键词： quasi-eutectic electrolyte aqueous zinc −manganese batteries solid −liquid interfacial state mass transfer charge transfer

Potential Effects of Episodic Deposition on Nutrients and Heavy Metals in Decomposing Litters of Suaeda glauca in Salt Marsh of the Yellow River Estuary, China

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Chinese Geographical Science 2020年第3期30卷 466-482页

作者： CHEN Bingbing SUN zhigao Key Laboratory of Humid Subtropical Eco-geographical Process(Fujian Normal University) Ministry of EducationFuzhou 350007China Institute of Geography Fujian Normal UniversityFuzhou 350007China Fujian Provincial Key Laboratory for Subtropical Resources and Environment Fujian Normal UniversityFuzhou 350007China

Episodic deposition has been recognized as a major factor affecting the decomposition rate of detrital material in salt marshes. In this paper, three one-off burial treatments, no burial treatment(0 cm, NBT), current burial treatment(10 cm, CBT) and strong burial treatment(20 cm, SBT), were designed in intertidal zone of the Yellow River Estuary to determine the potential influences of episodic deposition on nutrient(C, N) and heavy metal(Pb, Cr, Cu, Zn, Ni, Mn, Cd, V and Co) variations in decomposing litters of Suaeda glauca. Results showed that although various burial treatments showed no statistical difference in decomposition rate of S. glauca, the values generally followed the sequence of CBT(0.002 403/d) > SBT(0.002 195/d) > NBT(0.002 060/d). The nutrients and heavy metals in decomposing litters of the three burial treatments exhibited different variations except for N, Cu, Cr, Ni and Co. Except for Mn, no significant differences in C, N, Pb, Cr, Cu, Zn, Ni, V and Co concentrations occurred among the three treatments(P > 0.05). With increasing burial depth, Cr and Cd levels generally increased while Cu, Ni and Mn concentrations decreased. Although episodic deposition was generally favorable for C and N release from S. glauca, its influence on release was insignificant. In the three burial treatments, Pb, Cr, Zn, Ni, Mn, V and Co stocks in S. glauca generally evidenced the export of metals from litter to environment, and, with increasing burial depth, the export amounts increased greatly. The S. glauca were particular efficient in binding Cd and releasing Pb, Cr, Zn, Ni, Mn, V and Co, and, with increasing burial depth, stocks of Cu in decomposing litters generally shifted from release to accumulation. The experiment indicated that the potential eco-toxic risk of Pb, Cr, Zn, Ni, Mn, V and Co exposure would be serious as the strong burial episodes occurred in S. glauca marsh.

关键词： decomposition nutrient and metal episodic deposition Suaeda glauca Yellow River Estuary

Metal-organic framework-derived porous shuttle-like vanadium oxides for sodium-ion battery application

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Nano Research 2018年第1期11卷 449-463页

作者： Yangsheng Cai Guozhao fang Jiang Zhou Sainan Liu zhigao Luo Anqiang Pan Guozhong Cao I Shuquan Liang School of Materials Science and Engineering Central South University Changsha 410083 China Key Laboratory of Nonferrous Metal Materials Science and Engineering Ministry of Education Central South University Changsha 410083 China Department of Materials and Engineering University of Washington Seattle WA 98195-2120 USA

Vanadium oxides with a layered structure are promising candidates for both lithium-ion batteries and sodium-ion batteries （SIBs）. The self-template approach, which involves a transformation from metal-organic frameworks （MOFs） into porous metal oxides, is a novel and effective way to achieve desirable electrochemical performance. In this stud~ porous shuttle-like vanadium oxides （i.e., V205, V203/C） were successfully prepared by using MIL-88B （V） as precursors with a specific calcination process. As a proof-of-concept application, the as- prepared porous shuttle-like VaOdC was used as an anode material for SIBs. The porous shuttle-like V203/C, which had an inherent layered structure with metallic behavior, exhibited excellent electrochemical properties. Remarkable rate capacities of 417, 247, 202, 176, 164, and 149 mAh.g-1 were achieved at current densities of 50, 100, 200, 500, 1,000, and 2,000 mA.g-1, respectively. Under cycling at 2 A.g-1, the specific discharge capacity reached 181 mAh.g-1, with a low capacity fading rate of 0.032% per cycle after 1,000 cycles. Density functional theory calculation results indicated that Na ions preferred to occupy the interlamination rather than the inside of each layer in the V203. Interestingly, the special layered structure with a skeleton of dumbbell-like V-V bonds and metallic behavior was maintained after the insertion of Na ions, which was beneficial for the cycle performance. We consider that the MOF precursor of MIL-88B （V） can be used to synthesize other porous V-based materials for various applications.

关键词： vanadium oxides metal-organic frameworks porous structure density functional theory(DFT) calculation sodium-ion batteries

Magnetism and work function of Ni-Cu alloys as metal gates

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Rare Metals 2012年第2期31卷 130-134页

作者： Cheng, Yanming Zheng, Yongping Huang, Xu Zhong, Kehua Chen, zhigao Huang, zhigao Department of Physics Fujian Normal University Fuzhou 350007 China

The magnetism and work function of pure Ni(001) and Ni-Cu slab alloys were investigated using first-principles methods based on density functional theory. The calculated results reveal that both magnetic moments and work functions of the alloys depend strongly on the surface orientation, but hardly on the distribution of doped Cu atoms for a given surface orientation. It is found that the doped Cu atoms have evident influence on the magnetic moment of Ni-Cu slabs, and the average magnetic moment of Ni atoms for Ni-Cu alloys decreases with increasing concentration of Cu atoms. Moreover, it is observed that the work function of Ni(001) is insensitive to the supercell thickness and the inner concentration of Cu atoms. In the meantime, the spin polarization is found to have an obvious role on the work function of the Ni-Cu alloys, which may give a new way to modulate the work function of the metal gate.

关键词： first principles magnetism work function