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Diverse atomic structure configurations of metal-doped transition metal dichalcogenides for enhancing hydrogen evolution

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Nano Research 2024年第5期17卷 3586-3602页

作者： Longlu wang Yuxin Zhang Chen Gu Haoxuan Yu Yanling zhuang Zechao zhuang College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Jiangsu Province Engineering Research Center for Fabrication and Application of Special Optical Fiber Materials and DevicesNanjing University of Posts and TelecommunicationsNanjing 210023China Department of Chemical Engineering Columbia UniversityNew YorkNY 10027USA

Doping foreign metal atoms into the substrate of transition metal dichalcogenides(TMDs)enables the formation of diverse atomic structure configurations,including isolated atoms,chains,and ***,it is very important to reasonably control the atomic structure and determine the structure-activity relationship between the atomic configurations and the hydrogen evolution reaction(HER)*** numerous studies have indicated that doping can yield diverse atomic structure configurations,there remains an incomplete understanding of the relationship between atomic configurations within the lattice of TMDs and their ***,diverse atomic structure configurations of adsorptive doping,substitutional doping,and TMDs alloys are *** structure-activity relationship between different atomic configurations and HER performance can be determined by micro-nanostructure devices and density functional theory(DFT)*** diverse atomic structure configurations are of great significance for activating the inert basal plane of TMDs and improving the catalytic activity of ***,we have summarized the current challenges and future opportunities,offering new perspectives for the design of highly active and stable metal-doped TMDs catalysts.

关键词： transition metal dichalcogenides(TMDs) dopant effect diverse atomic structure configurations hydrogen evolution reaction(HER)

Synergistic effect of gradient Zn content and multiscale particles on the mechanical properties of Al-Zn-Mg-Cu alloys with coupling distribution of coarse-fine grains

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1392-1405页

作者： Liangliang Yuan Mingxing Guo Yi wang Yun wang Linzhong zhuang Institute of Effectiveness Evaluation of Flying Vehicle Beijing 100085China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

This study investigated the influence of graded Zn content on the evolution of precipitated and iron-rich phases and grain struc-ture of the alloys,designed and developed the Al–8.0Zn–1.5Mg–1.5Cu–0.2Fe(wt%)alloy with high strength and *** the increase of Zn content,forming the coupling distribution of multiscale precipitates and iron-rich phases with a reasonable matching ratio and dispersion distribution characteristics is *** phenomenon induces the formation of cell-like structures with alternate distribu-tion of coarse and fine grains,and the average plasticity–strain ratio(characterizing the formability)of the pre-aged alloy with a high strength is up to *** reveal the evolution and influence mechanisms of multiscale second-phase particles and the corresponding high formability mechanism of the *** developed coupling control process exhibits considerable potential,revealing remarkable improvements in the room temperature formability of high-strength Al–Zn–Mg–Cu alloys.

关键词： Al–Zn–Mg–Cu alloy iron-rich phase high formability microstructure mechanisms

Staring-imaging satellite pointing estimation based on sequential ISAR images

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Chinese Journal of Aeronautics 2024年第8期37卷 261-276页

作者： Canyu wang Libing JIANG Weijun ZHONG xiaoyuan REN zhuang wang National Key Laboratory of Automatic Target Recognition National University of Defense TechnologyChangsha 410073China Xi’an Satellite Control Center Xi’an 710600China

Pointing estimation for spacecraft using Inverse Synthetic Aperture Radar(ISAR)images plays a significant role in space situational awareness and ***,feature extraction and cross-range scaling of ISAR images create bottlenecks that limit performances of current estimation ***,the emergence of staring imaging satellites,characterized by complex kinematic behaviors,presents a novel challenge to this *** address these issues,this article proposes a pointing estimation method based on Convolutional Neural Networks(CNNs)and a numerical optimization algorithm.A satellite’s main axis,which is extracted from ISAR images by a proposed Semantic Axis Region Regression Net(SARRN),is chosen for investigation in this article due to its unique ***,considering the kinematic characteristic of the staring satellite,an ISAR imaging model is established to bridge the target pointing and the extracted *** on the imaging model,pointing estimation and cross-range scaling can be described as a maximum likelihood estimation problem,and an iterative optimization algorithm modified by using the strategy of random sampling-consistency check and weighted least squares is proposed to solve this ***,the pointing of targets and the cross-range scaling factors of ISAR images are *** experiments based on actual satellite orbital parameters verify the effectiveness of the proposed *** work can improve the performance of satellite reconnaissance warning,while accurate cross-range scaling can provide a basis for subsequent data processes such as 3D reconstruction and attitude estimation.

关键词： Staring-imaging Agile satellite Inverse Synthetic Aperture Radar(ISAR) Pointing estimation Cross-range scaling

Large area^(3)He tube array detector with modular design for multi‑physics instrument at CSNS

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Nuclear Science and Techniques 2023年第1期34卷 1-12页

作者： Lin Zhu Jian‑Rong Zhou Yuan‑Guang Xia Liang xiao Hong Luo xiao‑Juan Zhou Wen‑Qin Yang Bei‑Ju Guan Xing‑Fen Jiang Yan‑Feng wang Hong Xu Hai‑Yun Teng Li‑Xin Zeng Jia‑Jie Li Lei Hu Ke Zhou Yong‑Xiang Qiu Pei‑Xun Shen Jun Xu Li‑Jiang Liao xiao‑zhuang wang Gui‑An Yang Huai‑Chan Chen Ju‑Ping Xu Zhi‑Duo Li Song‑Lin wang Jian zhuang Yu‑Bin Zhao Jun‑Rong Zhang Wen Yin Zhi‑Jia Sun Yuan‑Bo Chen Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China University of Chinese Academy of Sciences Beijing 100049China

The multi-physics instrument(MPI)is the first user cooperative instrument at the China Spallation Neutron Source(CSNS).It was designed to explore the structures of complex materials at multiple scales based on the neutron total scattering *** imposes the requirements for the detector,including a high detection efficiency to reduce the measurement time and a large solid angle coverage to cover a wide range of momentum *** satisfy these demands,a large-area array of 3He-filled linear position-sensitive detectors(LPSDs)was constructed,each with a diameter of 1 inch and pressure of 20 *** uses an orbicular layout of the detector and an eight-pack module design for the arrangement of 3He LPSDs,covering a range of scattering angles from 3°to 170°with a total detector area of approximately 7 *** detector works in air,which is separated from the vacuum environment to facilitate installation and *** characteristics of the MPI detector were investigated through Monte Carlo(MC)simulations using Geant4 and experimental *** results suggest that the detectors are highly efficient in the wavelength range of the MPI,and an efficiency over 25%is achievable for above 0.1 A neutrons.A minimal position resolution of 6.4 mm full width at half maximum(FWHM)along the tube length was achieved at a working voltage of 2200 V,and a deviation below 2 mm between the real and measured positions was attained in the beam *** detector module exhibited good consistency and an excellent counting rate capacity of up to 80 kHz,which satisfied the requirements of experiments with a high event *** of its operation over the past year have shown that the detector works steadily in sample experiments,which allows the MPI to serve the user program successfully.

关键词： Neutron detector LPSD Position resolution Counting rate capacity

Large-aperture Telescope Tracking Control Based on Time-synchronization Strategy

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Research in Astronomy and Astrophysics 2024年第3期24卷 34-46页

作者： Yun Li Yu Ye Shi-Hai Yang Ling-Zhe Xu Jin Xu Hai wang zhuang-zhuang Deng Rui-Qiang Liu xiao-Jie Gu Bo-Zhong Gu Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China University of Chinese Academy of Sciences Beijing 100049China

A time-synchronization strategy for packetized transmission of target position about a large-aperture telescope observation control system has been proposed in this *** with the existing telescope tracking strategy,the target position packing and sending strategy based on the time synchronization method proposed in this paper has the advantages of high stability and ***,the telescope tracking observation control method was elaborated in this paper,including the motion pattern during telescope ***,the strategy for packetizes transmission of target positions based on time-synchronization is established and lists the detailed ***,the performance of the tracking strategy is verified using the 2.5 m telescope for the simulated uniform speed star and the blind-tracking fixed star HIP 31216,*** test results show that the accuracy root mean square of the tracking strategy proposed in this paper is less than 0".02 at 30 minutes,and the performance is much better than the design requirement of 0".*** most important advantage of this tracking strategy is that the telescope can guarantee normal tracking for a certain period of time even if the hardware or software of the host computer is abnormal.

关键词： miscellaneous-telescopes-methods observational-methods analytical

Security-Enhanced Directional Modulation Based on Two-Dimensional M-WFRFT

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China Communications 2024年第5期21卷 229-248页

作者： Zhou zhuang Luo Junshan wang Shilian Xia Guojiang School of Electronic Science National University of Defense TechnologyChangsha 410073China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

Directional modulation(DM)is one of the most promising secure communication ***,when the eavesdropper is co-located with the legitimate receiver,the conventional DM has the disadvantages of weak anti-scanning capability,anti-deciphering capability,and low secrecy *** response to these problems,we propose a twodimensional multi-term weighted fractional Fourier transform aided DM scheme,in which the legitimate receiver and the transmitter use different transform terms and transform orders to encrypt and decrypt the confidential *** order to further lower the probability of being deciphered by an eavesdropper,we use the subblock partition method to convert the one-dimensional modulated signal vector into a twodimensional signal matrix,increasing the confusion of the useful *** results demonstrate that the proposed DM scheme not only provides stronger anti-deciphering and anti-scanning capabilities but also improves the secrecy rate performance of the system.

关键词： bit error rate directional modulation phased array secrecy rate weighted fractional Fourier transform

GS-orthogonalization OMP method for space target detection via bistatic space-based radar

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Chinese Journal of Aeronautics 2024年第7期37卷 333-351页

作者： Shuyu ZHENG Libing JIANG Qingwei YANG Yingjian ZHAO zhuang wang National Key Laboratory of Science and Technology on Automatic Target Recognition College of Electronic Science and TechnologyNational University of Defense TechnologyChangsha 410073China

A space-based bistatic radar system composed of two space-based radars as the transmitter and the receiver respectively has a wider surveillance region and a better early warning capability for high-speed targets,and it can detect focused space targets more flexibly than the monostatic radar system or the ground-based radar ***,the target echo signal is more difficult to process due to the high-speed motion of both space-based radars and space *** be specific,it will encounter the problems of Range Cell Migration(RCM)and Doppler Frequency Migration(DFM),which degrade the long-time coherent integration performance for target detection and localization *** solve this problem,a novel target detection method based on an improved Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm is proposed in this ***,the echo model for bistatic space-based radar is constructed and the conditions for RCM and DFM are ***,the proposed GS-orthogonalization OMP method is applied to estimate the equivalent motion parameters of space ***,the RCM and DFM are corrected by the compensation function correlated with the estimated motion ***,coherent integration can be achieved by performing the Fast Fourier Transform(FFT)operation along the slow time direction on compensated echo *** simulations and real raw data results validate that the proposed GS-orthogonalization OMP algorithm achieves better motion parameter estimation performance and higher detection probability for space targets detection.

关键词： Bistatic space-based radar High-speed maneuvering space targets detection Range Cell Migration(RCM) Doppler Frequency Migration(DFM) Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm

Metabolic cell death in cancer:ferroptosis,cuproptosis,disulfidptosis,and beyond

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Protein & Cell 2024年第9期15卷 642-660页

作者： Chao Mao Min wang Li zhuang Boyi Gan Department of Experimental Radiation Oncology The University of Texas MD Anderson Cancer CenterHoustonTX 77030USA Department of Molecular and Cellular Biology Baylor College of MedicineHoustonTX 77030USA The University of Texas MD Anderson UTHealth Graduate School of Biomedical Sciences HoustonTX 77030USA

Cell death resistance represents a hallmark of *** studies have identified metabolic cell death as unique forms of regulated cell death resulting from an imbalance in the cellular *** review discusses the mechanisms of metabolic cell death—ferroptosis,cuproptosis,disulfidptosis,lysozincrosis,and alkaliptosis—and explores their potential in cancer *** review underscores the complexity of the metabolic cell death pathways and offers insights into innovative therapeutic avenues for cancer treatment.

关键词： cell death cancer treatment ferroptosis cuproptosis disulfidptosis

Surrounding rock classification from onsite images with deep transfer learning based on EfficientNet

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Frontiers of Structural and Civil Engineering 2024年第9期18卷 1311-1320页

作者： xiaoying zhuang Wenjie FAN Hongwei GUO Xuefeng CHEN Qimin wang Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Chair of Computational Science and Simulation Technology Institute of PhotonicsLeibniz University HannoverHannover 30167Germany Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China Guizhou Xingyi Huancheng Expressway Co. Ltd.Xingyi 562400China

This paper proposes an accurate,efficient and explainable method for the classification of the surrounding rock based on a convolutional neural network(CNN).The state-of-the-art robust CNN model(EfficientNet)is applied to tunnel wall image *** filtering,data augmentation and other data pre-processing techniques are used to improve the data quality and *** with transfer learning,the generality,accuracy and efficiency of the deep learning(DL)model are further improved,and finally we achieve 89.96%*** with other state-of-the-art CNN architectures,such as ResNet and Inception-ResNet-V2(IRV2),the presented deep transfer learning model is more stable,accurate and *** reveal the rock classification mechanism of the proposed model,Gradient-weight Class Activation Map(Grad-CAM)visualizations are integrated into the model to enable its explainability and *** developed deep transfer learning model has been applied to support the tunneling of the Xingyi City Bypass in the high mountain area of Guizhou,China,with great results.

关键词： surrounding rock classification convolutional neural network EfficientNet Gradient-weight Class Activation Map