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Anisotropic Behavior Analyzed by Laser-Generated Lamb Waves for Fiber Composite Plates

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Chinese Physics Letters 1999年第7期16卷 518-519页

作者： CHENG Jian-chun han jun-bo ZhanG Shu-yi Yves Berthelot Laboratory of Modern Acoustics and Institute of Acoustics Nanjing UniversityNanjing 210093 School of Mechanical Engineering Georgia Institute of Technology^AtlantaGA 30332USA

Analyses of the anisotropic behavior of a Uber composite plate from the laser-generated ultrasonic Lamb waveforms propagating in different directions are presented by employing wavelet transform *** time-frequency representation plots of the waveforms clearly exhibit the anisotropic behavior of the composite *** plots also indicate that the waveform mainly consists of three or four lower-order Lamb wave modes,and other higher-order modes can be neglected in extracting elastic stiffness properties by comparison of theory with experimental *** group velocity of each mode is calculated according to the group delay and the source-receiver distance.

关键词： composite anisotropic neglected

A Fluorine-Functionalized 3D Covalent Organic Framework with Entangled 2D Layers

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Chinese Journal of Polymer Science 2024年第8期42卷 1210-1216页

作者： Li-Bang Xiao Zi-han Wu jun-Jie Xin Yuan-Peng Cheng bo Gui jun-Liang Sun Cheng Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China College of Chemistry and Molecular Engineering Beijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871China

Constructing three dimensional(3D)covalent organic frameworks(COFs)through the entanglement of two dimensional(2D)nets is a promising but underdeveloped ***,we report the design and synthesis of a fluorine functionalized 3DCOF(3D-An-COF-F)formed by entangled 2D sql *** structure of 3D-An-COF-F was determined by the combination of continuous rotation electron diffraction technique and modelling based on the chemical information from real ***,compared to the isostructural 3D-An-COF without F atom s,3DAn-COF-F showed an improved CO_(2)sorption ability and higher CO_(2)/N_(2)*** study not only demonstrated the generality of constructing 3D COFs with entangled 2D nets by introducing bulky groups vertically in planar building blocks,but also will expand the diversity of 3D COFs for various applications.

关键词： 3D covalent organic frameworks Fluorine Entangled 2D layers Electron diffraction CO_(2)adsorption

Deflagration and detonation induced by shock wave focusing at different Mach numbers

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Chinese Journal of Aeronautics 2024年第2期37卷 249-258页

作者： Zezhong YANG jun CHENG bo ZhanG School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

Shock wave focusing is an effective way to create a hot spot or a high-pressure and hightemperature region at a certain place,showing its unique usage in detonation initiation,which is beneficial for the development of detonation-based *** flame propagation behavior after the autoignition induced by shock wave focusing is crucial to the formation and self-sustaining of the detonation *** this study,wedge reflectors with two different angles(60°and 90°)and a planar reflector are employed,and the Mach number of incident shock waves ranging from 2.0 to 2.8 is utilized to trigger different flame propagation *** pressure transducers and the high-speed schlieren imaging system are both employed to investigate the shock-shock collision and ignition *** results reveal a total of four flame propagation modes:deflagration,DDT(Deflagration-to-Detonation Transition),unsteady detonation,and direct *** detonation wave formed in the DDT and unsteady detonation mode is only approximately 75%-85%of the Chapman-Jouguet(C-J)speed;meanwhile,the directly induced detonation wave speed is close to the C-J *** waves,which are strong evidence for the existence of detonation waves,are discovered in *** usage of wedge reflectors significantly reduces the initial pressure difference ratio needed for direct detonation *** also provide a practical method for differentiating between detonation and deflagration modes,which involves contrasting the speed of the reflected shock wave with the speed of the theoretically nonreactive reflected shock *** findings should serve as a reference for the detonation initiation technique in advanced detonation propulsion engines.

关键词： Deflagration Detonation Hydrogen Ignition Shock wave focusing

A Multi-Stage Differential-Multifactorial Evolutionary Algorithm for Ingredient Optimization in the Copper Industry

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2135-2153页

作者： Xuerui Zhang Zhongyang han jun Zhao School of Control Science and Engineering Dalian University of TechnologyDalian 116024China IEEE

Ingredient optimization plays a pivotal role in the copper industry,for which it is closely related to the concentrate utilization rate,stability of furnace conditions,and the quality of copper *** acquire a practical ingredient plan,which should exhibit long duration time with sufficient utilization and feeding stability for real applications,an ingredient plan optimization model is proposed in this study to effectively guarantee continuous production and stable furnace *** address the complex challenges posed by this integer programming model,including multiple coupling feeding stages,intricate constraints,and significant non-linearity,a multi-stage differential-multifactorial evolution algorithm is *** the proposed algorithm,the differential evolutionary(DE)algorithm is improved in three aspects to efficiently tackle challenges when optimizing the proposed ***,unlike traditional time-consuming serial approaches,the multifactorial evolutionary algorithm is utilized to optimize multiple complex models contained in the population of evolutionary algorithm caused by the feeding stability in a parallel ***,a repair algorithm is employed to adjust infeasible ingredient lists in a timely *** addition,a local search strategy taking feedback from the current optima and considering the different positions of global optimum is developed to avoiding premature convergence of the differential evolutionary ***,the simulation experiments considering different planning horizons using real data from the copper industry in China are conducted,which demonstrates the superiority of the proposed method on feeding duration and stability compared with other commonly deployed *** is practically helpful for reducing material cost as well as increasing production profit for the copper industry.

关键词： Copper industry differential-multifactorial evolution ingredient optimization multi-stage optimization

A high-throughput model for screening anti-tumor agents capable of promoting polymerization of tubulin in vitro

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Acta Pharmacologica Sinica 2004年第6期25卷 73-80页

作者： Wei HU, Hui DONG, Yue-zhong LI2, Xi-tao HU, Guan-jun han, Yin-bo QU State KeyLaboratory of Microbial Technology, School of Life Science, Shandong University, Ji-nan 250100, China State Key Laboratory of Microbial Technology School of Life Science Shandong University Ji-nan 250100 China

AIM: To establish a high-throughput model for screening anti-tumor agents capable of promoting the polymeriza- tion of tubulin in vitro. METHODS: Tubulin was prepared in different purity for two screening steps. The first step was a high-throughput screening (HTS) for a set of 1500 samples using the GTP-containing tubulin and the end-reading method. The second step was performed on 119 hits from the first screening by a kinetic assay with GTP-lacking tubulin. RESULTS: The HTS for 1500 samples was accomplished in less than 3 h. From the screening, 108 samples were identified with >20 % promotion activity at 10 mg/L. Five of 108 were further confirmed by the kinetic assay using the purified tubulin subsequently. Three of the hit compounds were Epothilone A or its analogs, the other two compounds had new structures with a common pharmacophore for cytotoxic natural products that stabilize microtubules. In an MTT test, the five selected samples from the screening showed a minimal IC50 at0.28±0.06 nmol/Lto Helacells. CONCLUTION: The two-stepscreening methodis a high-throughtput, cost-effective, and efficient approach to identify microtubule-stabilizing agents.

关键词： antitumor drug screening assays tubulin polymerization promotor microtubules

Advanced Sensors Towards Ubiquitous Power Internet of Things

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 871-890页

作者： Jinliang He Zhifei han jun Hu Department of Electrical Engineering Tsinghua UniversityBeijing 100084China IEEE CSEE

The ubiquitous power Internet of Things(UPIoT)uses modern information technology and advanced communication technologies to realize interconnection and human-computer interaction in all aspects of the power *** has the characteristics of comprehensive state perception and efficient information processing,and has broad application prospects for transformation of the energy *** fundamental facility of the UPIoT is the sensor-based information *** using advanced sensors,Wireless Sensor Networks(WSNs),and advanced data processing technologies,Internet of Things can be realized in the power *** this paper,a framework of WSNs based on advanced sensors towards UPIoT is *** addition,the most advanced sensors for UPIoT purposes are reviewed,along with an explanation of how the sensor data obtained in UPIoT is utilized in various scenarios.

关键词： Advanced sensors ubiquitous power Internet of Things wireless sensor networks

Depositional Environment and Origin of Inertinite-rich Coal in the Ordos Basin

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 1064-1085页

作者： SHI Qingmin ZHAO jun JI Ruijun XUE Weifeng han bo CAI Yue LI Chunhao CUI Shidong College of Geology and Environment Xi’an University of Science and TechnologyXi’an 710054China Shaanxi Coal Chemical Industry Technology Research Institute Co. Ltd.Xi’an 710199China China National Logging Corporation Geological Research InstituteXi’an 710077China

Inertinite-rich coal is widely distributed in the Ordos Basin,represented by the No.2 coal seam of the Middle Jurassic Yan'an *** paper combined coal petrology and geochemistry to analyze the origin of inertinite,changes in the coal-forming environment and control characteristics of *** has shown that there are two forms of inertinite sources in the study *** typical fusinization,wildfire events also play a substantial role in inertinite *** are significant fluctuations in the coal-forming environment of samples at different *** samples were formed in dry forest swamp with low water levels and strong oxidation,which have a high inertinite content,and the samples formed in wet forest swamp and limnic showed low inertinite ***,the inertinite content of different origins does not fully correspond to the depositional environment characterized by dryness and *** inertinites were significantly influenced by climatic conditions,while pyrofusinite was not entirely controlled by climatic conditions but rather directly impacted by wildfire *** high oxygen level was the main factor causing widespread wildfire ***,the combination of wildfire activity and oxidation generates a high content of inertinite in the Middle Jurassic coal of the Ordos Basin.

关键词： inertinite-rich coal wildfire coal petrology geochemistry biomarkers depositional environment

A Simple Proof of ACC for Minimal Log Discrepancies for Surfaces

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Acta Mathematica Sinica,English Series 2024年第2期40卷 425-434页

作者： Jing jun han Yu Jie LUO Shanghai Center for Mathematical Sciences Fudan UniversityJiangwan CampusShanghai 200438P.R.China Department of Mathematics Johns Hopkins UniversityBaltimoreMD 21218USA

Following Shokurov's idea,we give a simple proof of the ACC conjecture for minimal log discrepancies for surfaces.

关键词： Ascending chain condition minimal log discrepancies minimal model program surface

A solution using only electromagnetic coils for relative pose control in satellite docking

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Chinese Journal of Aeronautics 2024年第3期37卷 258-281页

作者： Guangzheng RUAN Lijian WU bo WANG Yaobing WANG Runqi han College of Electrical Engineering Zhejiang UniversityHangzhou 310012China Beijing Institute of Spacecraft System Engineering Beijing 100094China

This paper proposes an electromagnetic coil topology and its control strategy,which can be incorporated into the electromagnetic docking device to achieve relative pose control in satellite *** target satellite has a main coil;the chaser satellite possesses a main coil of the same size accompanied by six and four evenly arranged secondary coils inside and outside the main coil,*** coil on the target satellite is DC energized,while the currents in the coils of the chaser satellite are *** remove the coupling between the pitch/yaw torque and translational force,the internal and external secondary coils of the chaser satellite interact with the main coil of the target satellite to perform the control of relative pitch/yaw and relative translation,respectively,so relative pose control can be *** torque and force vectors exerted by the secondary coils of the chaser satellite are synthesized onto the pitch and yaw axes of the body *** to their spatial composition relationship,the formulas are proposed,which obtain the magnetic moment vectors of the coils from the set torques and *** controllers regulating pitch/yaw,translation,and distance utilize a three-loop cascaded structure that consists of an outer position loop,a middle velocity loop and an inner current *** control strategy is verified by dynamics simulation.

关键词： Electromagnetic docking 6 degree of freedom Relative pose control Coil array Far field model Motion decoupling