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Tracking lithiation with transmission electron microscopy

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science China Chemistry 2024年第1期67卷 291-311页

作者： Xincheng Lei Jianxiong Zhao Jiayi Wang Dong Su Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China South China academy of Advanced optoelectronics&international academy of optoelectronics at zhaoqing South China Normal UniversityGuangzhou 510006China

Li-ion batteries(LIBs)have dominated energy-storage techniques for portable electronic devices and electric cars,and are expanding their territory into the large-scale energy *** energy storage of LIBs is realized by the reversible shuttle of lithium ions between *** is essential to track the lithium diffusion and obtain a profound insight into the lithiation mechanism during the work cycle of *** electron microscopy(TEM)is a powerful tool for the structural characterization,which can provide the information about the lithiation at the atomic *** this review,we summarize the research frontiers of TEM applications on *** introduce the techniques for the direct observation of Li species in LIB-related ***,the application of cryo-TEM is ***,in-situ TEM technique is further discussed since it shows great advantages in studying the dynamical structure changes of *** perspectives and strategies in this review offer feasible guidance for researchers to further improve the performance of LIBs.

关键词： lithium-ion battery electrode materials transmission electron microscopy cryo-TEM in-situ TEM

In situ calibrated angle between the quantization axis and the propagating direction of the light field for trapping neutral atoms

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Chinese Physics B 2024年第2期33卷 318-323页

作者：郭瑞军何晓东盛诚王坤鹏许鹏刘敏王谨孙晓红曾勇詹明生 Henan Key Laboratory of Laser and optoelectronic information National Center for International Joint Research of Electronic Materials and SystemsSchool of Electrical and Information EngineeringZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China

The recently developed magic-intensity trapping technique of neutral atoms efficiently mitigates the detrimental effect of light shifts on atomic qubits and substantially enhances the coherence time. This technique relies on applying a bias magnetic field precisely parallel to the wave vector of a circularly polarized trapping laser field. However, due to the presence of the vector light shift experienced by the trapped atoms, it is challenging to precisely define a parallel magnetic field, especially at a low bias magnetic field strength, for the magic-intensity trapping of85Rb qubits. In this work, we present a method to calibrate the angle between the bias magnetic field and the trapping laser field with the compensating magnetic fields in the other two directions orthogonal to the bias magnetic field direction. Experimentally, with a constantdepth trap and a fixed bias magnetic field, we measure the respective resonant frequencies of the atomic qubits in a linearly polarized trap and a circularly polarized one via the conventional microwave Rabi spectra with different compensating magnetic fields and obtain the corresponding total magnetic fields via the respective resonant frequencies using the Breit–Rabi formula. With known total magnetic fields, the angle is a function of the other two compensating magnetic ***, the projection value of the angle on either of the directions orthogonal to the bias magnetic field direction can be reduced to 0(4)° by applying specific compensating magnetic fields. The measurement error is mainly attributed to the fluctuation of atomic temperature. Moreover, it also demonstrates that, even for a small angle, the effect is strong enough to cause large decoherence of Rabi oscillation in a magic-intensity trap. Although the compensation method demonstrated here is explored for the magic-intensity trapping technique, it can be applied to a variety of similar precision measurements with trapped neutral atoms.

关键词： quantization axis trapping laser angle compensating magnetic fields

TransTM:A device-free method based on time-streaming multiscale transformer for human activity recognition

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Defence Technology（防务技术） 2024年第2期32卷 619-628页

作者： Yi Liu Weiqing Huang Shang Jiang Bobai Zhao Shuai Wang Siye Wang Yanfang Zhang Institute of information engineering Chinese academy of sciences School of Cyber SecurityUniversity of Chinese Academy of SciencesBeijingChina school of information Management Beijing Information Science and Technology UniversityBeijingChina

RFID-based human activity recognition(HAR)attracts attention due to its convenience,noninvasiveness,and privacy *** RFID-based HAR methods use modeling,CNN,or LSTM to extract features ***,they have shortcomings:1)requiring complex hand-crafted data cleaning processes and 2)only addressing single-person activity recognition based on specific RF *** solve these problems,this paper proposes a novel device-free method based on Time-streaming Multiscale Transformer called *** model leverages the Transformer's powerful data fitting capabilities to take raw RFID RSSI data as input without ***,we propose a multiscale convolutional hybrid Transformer to capture behavioral features that recognizes singlehuman activities and human-to-human *** with existing CNN-and LSTM-based methods,the Transformer-based method has more data fitting power,generalization,and ***,using RF signals,our method achieves an excellent classification effect on human behaviorbased classification *** results on the actual RFID datasets show that this model achieves a high average recognition accuracy(99.1%).The dataset we collected for detecting RFID-based indoor human activities will be published.

关键词： Human activity recognition RFID Transformer

Flexible planar micro supercapacitor diode

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Journal of Energy Chemistry 2024年第6期93卷 429-435,I0011页

作者： Yihui Ma Pei Tang Zhenyuan Miao Wuyang Tan Qijun Wang Yuecong Chen Guosheng Li Qingyun Dou Xingbin Yan Lingling Shui Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and DevicesSchool of Information and Optoelectronic Science and Engineering&South China Academy of Advanced OptoelectronicsGuangzhou 510006GuangdongChina Department of Materials science and engineering Sun Yat-Sen UniversityGuangzhou 510275GuangdongChina College of Materials science and engineering Guilin University of TechnologyGuilin 541004GuangxiChina

Supercapacitor diode is a novel ion device that performs both supercapacitor energy storage and ion diode rectification ***,previously reported devices are limited by their large size and complex *** this work,we demonstrate a screen-printed micro supercapacitor diode(MCAPode)that based on the insertion of a finger mode with spinel ZnCo_(2)O_(4) as cathode and activated carbon as anode for the first time,and featuring an excellent area specific capacitance(1.21 mF cm^(-2)at 10 mV s^(-1))and high rectification characteristics(rectification ratioⅠof 11.99 at 40 mV s^(-1)).Taking advantage of the ionic gel electrolyte,which provides excellent stability during repeated flexing and at high *** addition,MCAPode exhibits excellent electrochemical performance and rectification capability in"AND"and"OR"logic *** findings provide practical solutions for future expansion of micro supercapacitor diode applications.

关键词： Micro devices Supercapacitor diodes Screen-printing Rectification Logic gates

Drug-Target Interactions Prediction Based on Signed Heterogeneous Graph Neural Networks

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Chinese Journal of Electronics 2024年第1期33卷 231-244页

作者： Ming CHEN Yajian JIANG Xiujuan LEI Yi PAN Chunyan JI Wei JIANG College of information science and engineering Hunan Normal University school of Computer science Shaanxi Normal University Faculty of Computer science and Control engineering Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences Computer science Department BNU-HKBU United International College

Drug-target interactions(DTIs) prediction plays an important role in the process of drug *** computational methods treat it as a binary prediction problem, determining whether there are connections between drugs and targets while ignoring relational types information. Considering the positive or negative effects of DTIs will facilitate the study on comprehensive mechanisms of multiple drugs on a common target, in this work, we model DTIs on signed heterogeneous networks, through categorizing interaction patterns of DTIs and additionally extracting interactions within drug pairs and target protein pairs. We propose signed heterogeneous graph neural networks(SHGNNs), further put forward an end-to-end framework for signed DTIs prediction, called SHGNN-DTI,which not only adapts to signed bipartite networks, but also could naturally incorporate auxiliary information from drug-drug interactions(DDIs) and protein-protein interactions(PPIs). For the framework, we solve the message passing and aggregation problem on signed DTI networks, and consider different training modes on the whole networks consisting of DTIs, DDIs and PPIs. Experiments are conducted on two datasets extracted from Drug Bank and related databases, under different settings of initial inputs, embedding dimensions and training modes. The prediction results show excellent performance in terms of metric indicators, and the feasibility is further verified by the case study with two drugs on breast cancer.

关键词： Drugs Training Proteins Measurement Message passing Prediction methods Graph neural networks

Field induced Chern insulating states in twisted monolayer–bilayer graphene

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Chinese Physics B 2024年第6期33卷 69-73页

作者：王政文韩英卓 Kenji Watanabe Takashi Taniguchi 姜宇航毛金海 school of Physical science and CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China College of Materials science and optoelectronic Technology Center of Materials Science and Optoelectronics EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China Advanced Materials Laboratory National Institute for Materials ScienceTsukuba 305-0044Japan

Unraveling the mechanism underlying topological phases, notably the Chern insulators(Ch Is) in strong correlated systems at the microscopy scale, has captivated significant research interest. Nonetheless, Ch Is harboring topological information have not always manifested themselves, owing to the constraints imposed by displacement fields in certain experimental configurations. In this study, we employ density-tuned scanning tunneling microscopy(DT-STM) to investigate the Ch Is in twisted monolayer–bilayer graphene(t MBG). At zero magnetic field, we observe correlated metallic *** under a magnetic field, a metal–insulator transition happens and an integer Ch I is formed emanating from the filling index s = 3 with a Chern number C = 1. Our results underscore the pivotal role of magnetic fields as a powerful probe for elucidating topological phases in twisted Van der Waals heterostructures.

关键词： Chern insulators strong correlation effects two-dimensional van der Waals heterostructure density-tuned scanning tunneling microscopy(DT-STM)

Sub-10-nm-sized Au@AuxIr1-x metal-core/alloy-shell nanoparticles as highly durable catalysts for acidic water splitting

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National science Review 2024年第4期11卷 130-140页

作者： Huimin Wang Zhe-ning Chen Yuanyuan Wang Dongshuang Wu Minna Cao Fanfei Sun Rong Cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese academy of sciences school of Materials science and engineering Nanyang Technological University Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied Physics Chinese Academy of Sciences Fujian science & Technology Innovation Laboratory for optoelectronic information of China

The absence of efficient and durable catalysts for oxygen evolution reaction（OER） is the main obstacle to hydrogen production through water splitting in an acidic ele ***,we report a controllable synthesis method of surface IrOxwith changing Au/Ir compositions by constructing a range of sub-10-nm-sized core-shell nanocatalysts composed of an Au core and AuxIr1-xalloy *** particular,Au@Au0.43Ir0.57exhibits 4.5 times higher intrinsic OER activity than that of the commercial Ir/*** X-ray-based spectroscopies,electron microscopy and density functional theory calculations revealed a balanced binding of reaction intermediates with enhanced *** water-splitting cell using a load of 0.02 mgIr/cm2of Au@Au0.43Ir0.57as both anode and cathode can reach 10 mA/cm2at 1.52 V and maintain activity for at least194 h,which is better than the cell using the commercial couple Ir/C‖Pt/C（1.63 V,0.2 h）.

关键词： controllable synthesis of surface IrOx oxygen evolution reaction acidic water splitting catalytic stability transition metal catalysts

The Exchange Attack and the Mixture Differential Attack Revisited: From the Perspective of Automatic Evaluation

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Chinese Journal of Electronics 2024年第1期33卷 19-29页

作者： Kexin QIAO Zhiyu ZHANG Zhongfeng NIU Liehuang ZHU school of Cyberspace science and Technology Beijing Institute of Technology State Key Laboratory of Cryptology Institute of information engineering Chinese Academy of Sciences school of Cryptography University of Chinese Academy of Sciences

Recent results show that the differential properties within quadruples boom as a new inspiration in cryptanalysis of Advanced Encryption Standard(AES)-like constructions. These methods include the exchange attack proposed in Asiacrypt’19, the mixture differential attack proposed in To SC’18, etc., where the essential properties are obtained by manually scrutinizing the structures of the AES-like constructions. This paper presents a novel framework and an automatic tool based on mixed integer linear programming to search for mixture differential distinguishers for general constructions. This framework considers what equality patterns among quadruples can make a distinguisher and traces how the patterns propagate through cipher components with accurate probability *** this tool, a 5-round AES distinguishing attack with lower complexity and more 6-round distinguishing attacks in the chosen plaintext scenarios are deduced. We prove that no exchange-type or mixture differential distinguisher exists for 7 and above rounds AES if the details of the Sbox and Mix Columns matrix are not taken into account.

关键词： Ciphers Estimation Encryption Mixed integer linear programming Complexity theory Standards

SAT-Based Automatic Searching for Differential and Linear Trails: Applying to CRAX

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Chinese Journal of Electronics 2024年第1期33卷 72-79页

作者： Yiyi HAN Caibing WANG Zhongfeng NIU Lei HU State Key Laboratory of information Security Institute of Information Engineering Chinese Academy of Sciences school of Cyber Security University of Chinese Academy of Sciences

Boolean satisfiability problem(SAT) is now widely applied in differential cryptanalysis and linear cryptanalysis for various cipher *** generated many excellent results for some ciphers,for example,*** this research,we study the differential and linear propagations through the operations of addition,rotation and XOR(ARX),and construct the SAT *** apply the models to CRAX to search differential trails and linear trails *** this sense,our contnbution can be broadly divided into two *** give the bounds for differential and linear cryptanalysis of Alzette both up to 12 steps,by which we present a 3-round differential attack and a 3-round linear attack for *** construct a 4-round key-recovery attack for CRAX with time complexity289times of 4-round encryption and data complexity 225.

关键词： Ciphers Encryption Complexity theory Time complexity