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Nano Research 2024年第7期17卷 5914-5921页

作者： Chun-Ying Chen Qi-Jie Mo fu-Zhen li Hai-li Song li Zhang MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon ***,we reported the precise immobilization of metal single atoms(M-SAs;M=Ru,Rh,Ir,Pd,Pt,and Au)into a porphyrinic metalorganic framework(MOF)of PCN-222(PCN=porous coordination network),and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene *** solvent-free conditions,Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room *** and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates,which helped to condense the substrates in the cavities of the porous *** density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway.

关键词： alkene hydrosilylation single atom catalysts metal-organic frameworks precision chemistry synergistic catalysis

Single-celled metasurface for labeled vortex beam generator

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Journal of Materiomics 2024年第4期10卷 811-818页

作者： Congling liang Qi Dai Tian huang Hong-Chao liu Zhiqiang Guan Rao fu Jin Tao Zile li Shaohua Yu Guoxing zheng Electronic Information School and School of MicroelectronicsWuhan UniversityWuhan430072China Wuhan Institute of Quantum Technology Wuhan430206China Peng Cheng Laboratory Shenzhen518055China Suzhou Institute of Wuhan University Suzhou215123China Institute of Applied Physics and Materials Engineering University of MacaoAvenida da UniversidadeTaipaMacao SARMacao999078China State Key Laboratory of Optical Communication Technologies and Networks China Information Communication Technologies Group Corporation(CICT)Wuhan430074China

Vortex light is a unique beam characterized by a spiral phase as it propagates. A fundamental parameter of vortex light is the topological charge, which determines the amount of angular momentum and plays a crucial role in tailoring its behavior. However, conventional measurement methods for determining the topological charge, such as those based on interference and phase modulation, tend to be intricate and complex. In this regard, a labeled vortex beam generator is proposed, composed of a metasurface with a single-celled configuration. When the metasurface is illuminated by light of the designed wavelength, the outgoing light exhibits a vortex structure. furthermore, the topological charge numbers can be directly observed with distinct labeled patterns when the metasurface is placed in an orthogonal-polarized optical path. With advantages such as ultra-compactness, high robustness, and exceptional precision, the proposed metasurface exhibits significant potential for applications in optical communication, light manipulation, optical sensing, etc.

关键词： Metasurface Vortex beam generator Topological charge

From Euler disk to phonon bottleneck effect: Excited state physics

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The Innovation 2024年第3期5卷 7-8页

作者： Xinnian lin Shaohua fu Yanni Zhai Wenhui Wang Haochen li Ruizhi Zhang Sheng meng Jimin Zhao School of Physics Xi’an Jiaotong UniversityXi’an 710049China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

The Euler disk,known since 1765,1 describes a solid disk that rotates on a smooth,firm surface,similar to a coin spun by a finger on a table,before its energy dissipates and it falls on the table.2 It represents a typical nonequilibrium excited state in classical *** most striking characteristic of an Euler disk is that it exhibits a sharply enhanced sound frequency when approaching the critical time,tc,after which the disk instantly ceases rotation and *** the excited-state-to-ground-state transition,its frequency abruptly changes from infinite to *** quasi-divergent and suddenly disappearing behavior is intriguing,revealing that this is a shared physical property in the microscopic quantum regime.

关键词： state excited sharply

Influence of water coupling coefficient on the blasting effect of red sandstone specimens

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International Journal of Coal Science & Technology 2024年第1期11卷 148-166页

作者： Yang li Renshu Yang Yanbing Wang Dairui fu School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China

This study investigates the impact of different water coupling coefficients on the blasting effect of red *** analysis is based on the theories of detonation wave and elastic wave,focusing on the variation in wall pressure of the blasting *** DDNP explosive as the explosive load,blasting tests were conducted on red sandstone specimens with four different water coupling coefficients:1.20,1.33,1.50,and *** study examines the morphologies of the rock specimens after blasting under these different water coupling ***,the fractal dimensions of the surface cracks resulting from the blasting were calculated to provide a quantitative evaluation of the extent of rock *** scanning and 3D reconstruction were performed on the post-blasting specimens to visually depict the extent of damage and fractures within the ***,the volume fractal dimension and damage degree of the post-blasting specimens are *** findings are then combined with numerical simulation to facilitate auxiliary *** results demonstrate that an increase in the water coupling coefficient leads to a reduction in the peak pressure on the hole wall and the crushing zone,enabling more of the explosion energy to be utilized for crack propagation following the *** specimens exhibited distinct failure patterns,resulting in corresponding changes in fractal *** simulated pore wall pressure–time curve validated the derived theoretical results,whereas the stress cloud map and explosion energy-time curve demonstrated the buffering effect of the water *** the water coupling coefficient increases,the buffering effect of the water medium becomes increasingly prominent.

关键词： Water coupling coefficient Radial uncoupled charge Numerical simulation Fractal dimension

General Method of Combining Grover and Simon for Attacking Block Ciphers

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China Communications 2024年第6期21卷 237-245页

作者： fu Xiangqun Bao Wansu Shi Jianhong li Tan Henan Key Laboratory of Quantum Information and Cryptography PLA SSF IEUZhengzhou 450001China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China

The compatibility of different quantum algorithms should be considered when these algorithms are *** this paper,the method of combining Grover and Simon is studied for the first time,under some preconditions or ***,we give two preconditions of applying Grover’s algorithm,which ensure that the success probability of finding the marked element is close to ***,based on these two preconditions,it is found out that the success probability of the quantum algorithm for FXconstruction is far less than ***,we give the design method of the Oracle function,and then present the general method of combining Grover and Simon algorithm for attacking block ciphers,with success probability close to 1.

关键词： block ciphers post-quantum crypto quantum algorithms

MSC-YOLO:Improved YOLOv7 Based on Multi-Scale Spatial Context for Small Object Detection in UAV-View

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Computers, Materials & Continua 2024年第4期79卷 983-1003页

作者： Xiangyan Tang Chengchun Ruan Xiulai li Binbin li Cebin fu School of Computer Science and Technology Hainan UniversityHaikou570228China Hainan Blockchain Technology Engineering Research Center Hainan UniversityHaikou570228China School of Cyberspace Security(School of Cryptology) Hainan UniversityHaikou570228China

Accurately identifying small objects in high-resolution aerial images presents a complex and crucial task in thefield of small object detection on unmanned aerial vehicles(UAVs).This task is challenging due to variations inUAV flight altitude,differences in object scales,as well as factors like flight speed and motion *** enhancethe detection efficacy of small targets in drone aerial imagery,we propose an enhanced You Only Look Onceversion 7(YOLOv7)algorithm based on multi-scale spatial *** build the MSC-YOLO model,whichincorporates an additional prediction head,denoted as P2,to improve adaptability for small *** replaceconventional downsampling with a Spatial-to-Depth Convolutional Combination(CSPDC)module to mitigatethe loss of intricate feature details related to small ***,we propose a Spatial Context Pyramidwith Multi-Scale Attention(SCPMA)module,which captures spatial and channel-dependent features of smalltargets acrossmultiple *** module enhances the perception of spatial contextual features and the utilizationof multiscale feature *** the Visdrone2023 and UAVDT datasets,MSC-YOLO achieves remarkableresults,outperforming the baseline method YOLOv7 by 3.0%in terms ofmean average precision(mAP).The MSCYOLOalgorithm proposed in this paper has demonstrated satisfactory performance in detecting small targets inUAV aerial photography,providing strong support for practical applications.

关键词： Small object detection YOLOv7 multi-scale attention spatial context

Forecasting supernova observations with the CSST:*** samples

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 164-177页

作者： Chengqi liu Youhua Xu Xianmin meng Xin Zhang Shi-Yu li Yuming fu Xiaofeng Wang Shufei liu Zun Luo Guanghuan Wang Hu Zhan Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Beijing Planetarium Beijing Academy of Science and TechnologyBeijing 100044China Leiden Observatory Leiden UniversityNL-2300 RA LeidenThe Netherlands Kapteyn Astronomical Institute University of GroningenNL-9700 AV GroningenThe Netherlands Physics Department Tsinghua UniversityBeijing 100084China School of Astronomy and Space Science University of ChineseAcademy of SciencesBeijing 100049China

The China Space Station Telescope(CSST,also known as Xuntian)is a serviceable two-meter-aperture wide-field telescope operating in the same orbit as the China Space *** CSST plans to survey a sky area of 17,500 deg^(2)of the medium-to-high Galactic latitude to a depth of 25-26 AB mag in at least 6 photometric bands over 255-1,000 *** such a large sky area,slitless spectra will also be taken over the same wavelength range as the imaging *** though the CSST survey is not dedicated to time-domain studies,it would still detect a large number of transients,such as supernovae(SNe).In this paper,we simulate photometric SN observations based on a strawman survey plan using the Sncosmo *** its 10-year survey,the CSST is expected to observe about 5 million SNe of various *** quality cuts,we obtain a“gold”sample that comprises roughly 7,400 SNe Ia,2,200 SNe Ibc,and 6,500 SNeⅡcandidates with correctly classified percentages reaching 91%,63%,and 93%(formally defined as classification precision),*** same survey can also trigger alerts for the detection of about 15,500 SNe Ia(precision 61%)and 2,100 SNeⅡ(precision 49%)candidates at least two days before the light ***,the near-ultraviolet observations of the CSST will be able to catch hundreds of shock-cooling events serendipitously every *** results demonstrate that the CSST can make a potentially significant contribution to SN studies.

关键词： space-based ultraviolet optical and infrared telescopes supernovae data analysis

Nphos:Database and Predictor of Protein N-phosphorylation

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Genomics, Proteomics & Bioinformatics 2024年第3期22卷 139-151页

作者： Ming-Xiao Zhao Ruo-Fan Ding Qiang Chen Junhua meng fulai li Songsen fu Biling huang Yan liu Zhi-liang Ji Yufen Zhao Institute of Drug Discovery Technology Ningbo UniversityNingbo 315211China Department of Chemical Biology Key Laboratory for Chemical Biology of Fujian ProvinceCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory of Cellular Stress Biology School of Life SciencesFaculty of Medicine and Life SciencesXiamen UniversityXiamen 361102China Zhejiang Key Laboratory of Pathophysiology Department of Biochemistry and Molecular BiologyHealth Science CenterNingbo UniversityNingbo 315211China BGI Genomics BGI-ShenzhenShenzhen 518083China Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084China

Protein N-phosphorylation is widely present in nature and participates in various biological ***,current knowledge on N-phosphorylation is extremely limited compared to that on *** this study,we collected 11,710 experimentally verified N-phosphosites of 7344 proteins from 39 species and subsequently constructed the database Nphos to share up-to-date information on protein *** these substantial data,we characterized the sequential and structural features of protein ***,after comparing hundreds of learning models,we chose and optimized gradient boosting decision tree(GBDT)models to predict three types of human N-phosphorylation,achieving mean area under the receiver operating characteristic curve(AUC)values of 90.56%,91.24%,and 92.01%for pHis,pLys,and pArg,***,we discovered 488,825 distinct N-phosphosites in the human *** models were also deployed in Nphos for interactive N-phosphosite *** summary,this work provides new insights and points for both flexible and focused investigations of *** will also facilitate a deeper and more systematic understanding of protein N-phosphorylation modification by providing a data and technical *** is freely available at http://***/Nphos/and http://***/Nphos/.

关键词： N-phosphorylation Post-translational modification Machine learning Database Benchmark dataset

light weight design and integrated method for manufacturing hydraulic wheel-legged robots

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第9期25卷 701-715页

作者： Xu li Haoyang YU huaizhi ZONG Haibo FENG Yili fu State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China

Design and manufacturing play pivotal roles in hydraulic-driven robotic ***,previous studies have emphasized mainly results and performance,often overlooking the specifics of the design and manufacturing *** paper introduces a novel approach known as light weight design and integrated manufacturing(LD&IM)for hydraulic wheel-legged *** LD&IM method leverages topology optimization and generative design techniques to achieve a substantial 45%weight reduction,enhancing the robot’s dynamic motion *** innovative design method not only streamlines the design process but also upholds the crucial attributes of light weight construction and high strength essential for hydraulic wheel-legged ***,the integrated manufacturing method,incorporating selective laser melting(SLM)and high-precision subtractive manufacturing(SM)processes,expedites the fabrication of high-quality *** the LD&IM approach,a hydraulic-driven single wheel-legged robot,denoted as WLR-IV,has been successfully *** robot boasts low mass and inertia,high strength,and a simplified component *** assess its dynamic jumping capabilities,the control loop integrates a linear quadratic regulator(LQR)and zero dynamic-based controller,while trajectory planning uses the spring-loaded inverted pendulum(SliP)*** jumping results confirm the WLR-IV single-legged robot’s exceptional dynamic performance,validating both the effectiveness of the LD&IM method and the rationale behind the control strategy.

关键词： Wheel-legged robot Hydraulic driven Topology optimization Wheel-legged robot Hydraulic driven Topology optimization Additive manufacturing(AM) Jump control

Towards rational design in electrochemical denitrification by analyzing pH dependence

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National Science Review 2024年第6期11卷 223-232页

作者： huan li Dong Luan Jun Long Xiaoyan fu Jianping Xiao State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

A small fraction of NOx（<1%） always exists in CO2feedstock（e.g. exhausted gas）, which can significantly reduce the efficiency of CO2electroreduction by ～30%. Hence, electrochemical denitrification is the precondi... 详细信息

A small fraction of NOx（further supported by more than 35 experiments over varying catalysts（Fe, Ni, Pd, Cu, Co, Pt and Ag）, partial pressures（20%, 50% and100%） and potentials（from -0.2 to 0.2 V vs. reversible hydrogen electrode）. All in all, the insights herein overturn long-lasting views in the field of NO electroreduction and suggest that rational design should steer away from catalyst engineering toward reactor optimization.

关键词： electrocatalysis denitrification pH-dependence nitric oxide reduction reaction mechanism