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Journal of Iron and Steel Research International 2024年第3期31卷 660-669页

作者： Shuang Liu Chen Du Cong Zhang Zhen-hua Bai key lab of Industrial Computer Control Engineering of hebei province Yanshan UniversityQinhuangdao 066004HebeiChina National Engineering Research Center for Equipment and technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004HebeiChina

An anti-saturation fault-tolerant adaptive torsional vibration control method with fixed-time prescribed performance for the rolling mill main drive system(RMMDS)was investigated,which is affected by control input saturation,actuator faults,sensor measurement errors,and parameter ***,we gave a continuously differentiable saturation function to approximate the control input saturation characteristic of the RMMDS,translating the saturation characteristic into the matched uncertainty and unknown time-varying gain in the ***,an RMMDS mathematical model with unmatched uncertainty and unknown time-varying gain was developed,taking into account the presence of control input saturation,actuator faults,sensor measurement errors,and parameter *** on the established mathematical model,an error transformation model of the roll speed tracking was constructed by the equivalent error transformation *** to the error transformation model,a barrier Lyapunov function and a novel adaptive controller were studied to ensure that the roll speed tracking error always evolves inside a fixed-time asymmetric ***,numerical simulations were performed in Matlab/Simulink to verify the effectiveness and superiority of the proposed control method in suppressing the RMMDS torsional vibration.

关键词： Fixed-time prescribed performance Control input saturation Actuator fault Unknown time-varying gain Adaptive control Asymmetric constraint

Analysis of the Flow Field and Impact Force in High-Pressure Water Descaling

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Fluid Dynamics & Materials Processing 2024年第1期20卷 165-177页

作者： Yue Cui Liyuan Wang Jian Wu Haisheng Liu Di Wu key lab of Intelligent Equipment Digital Design and Process Simulation Hebei ProvinceTangshan UniversityTangshan063000China Department of Intelligent Manufacturing Tangshan Vocational College of Science and TechnologyTangshan063001China

This study aims to improve the performances of the high-pressure water descaling technology used in steel hot rolling *** particular,a 2050 mm hot rolling line is considered,and the problem is investigated by means of a fluid–structure interaction(FSI)method by which the descaling effect produced by rolling coils with different section sizes is *** a flat fan-shaped nozzle at the entrance of the R1R2 roughing mill,the outflow field characteristics and the velocity distribution curve on the strike line(at a target distance of 30–120 mm)are *** is found that the velocity in the center region of the water jet with different target distances is higher than that in the boundary *** the target distance increases,the velocity of the water jet in the central region *** comparison with experimental results,it is shown that the simulation model can accurately predict the impact position of the high-pressure water on the impact plate,thereby providing a computational scheme that can be used to optimize the nozzle space layout and improve the slabs’descent effect for different rolling specifications.

关键词： High pressure water descaling flow field analysis FSI target distance strike range

A highoutput PDMS-MXene/gelatin triboelectric nanogenerator with the petal surface-microstructure

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Nano Research 2024年第5期17卷 4151-4162页

作者： Zekun Wang Congcong Hao Mingzhe Cai Juan Cui Yongqiu Zheng Chenyang Xue key laboratory of instrumentation Science&Dynamic measurement Ministry of Education North University of ChinaTaiyuan 030051China State key laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 611731China

Triboelectric nanogenerator(TENG)has a promising future in the field of energy harvesting and self-powered sensing due to their simplicity in structure,low cost,and efficient energy harvesting from the surrounding *** output electrical performance of TENG can be improved by doping the friction material with functional materials and modifying the surface of the friction ***,the current method of adding functional materials to friction materials is costly and wasteful,and the method of modifying the surface structure of friction materials is cumbersome and not easy to *** this work,we present a polydimethylsiloxane(PDMS)-MXene/gelatin triboelectric nanogenerator(PMMG-TENG)based on petal surface-microstructures,which has the advantages of low cost,simple preparation,high output performance,and ecological *** doping 0.03 wt.%of MXene in PDMS,the output electrical performance of TENG can be significantly improved,with an output current increase of up to 139.7%.Four different petals are used as natural molds to prepare *** results show that PMMG-TENG with peony petal surface microstructure has the best electrical performance,and the output current increase of up to 228.17%compared with PMMG-TENG without *** PMMG-TENG with peony petal surface-microstructure exhibits excellent electrical performance,demonstrating a maximum open-circuit voltage of 417.39 V and a maximum short-circuit current of 12.01μA at a size of 3 cm×3 cm,and a maximum power density of 170μW/cm^(2) at a load resistance of 107Ω.The PMMG-TENG’s output performance after 10,000 cycles is consistent with the initial state,highlighting excellent output *** PMMG-TENG can easily light up at least 100 light emitting diodes(LEDs).(operating voltage 3V.)Gelatin film exhibits excellent degradation performance,with complete degradation time of only 150 s in water at a constant temperature of 75℃.PMMG-TENG not only shows excellent performance in

关键词： triboelectric nanogenerator(TENG) petal surface-microstructure gelatin MXene energy harvesting

Two sandwich-type uranyl-containing polytungstates catalyze aerobic synthesis of benzimidazoles

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Rare Metals 2024年第3期43卷 1316-1322页

作者： Yu-Feng Liu Qi-Long Hu Xue-Jiao Chen Ke Li Pei Luo Guo-Ping Yang School of Chemistry and Material Science Jiangxi Province Key Laboratory of Synthetic ChemistryJiangxi Key Laboratory for Mass Spectrometry and InstrumentationEast China University of TechnologyNanchang330013China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen518055China

Diversified synthetic strategies are extremely important for the structural diversity of uranium-containing polyoxometalates(U-POMs)and their functional ***,two sandwich-type U-POMs were reported,which are Na_(5.6)K_(6.4)[(UO_(2))(H_(2)O)(TeW_(9)O_(33))]_(2)·21H_(2)O(UTeW_(9))and Na_(8.9)K_(2.7)H_(1.19)[K_(0.79)(UO_(2))_(2.21)(PW_(9)O_(34))_(2)]·12H_(2)O(UPW_9)using in-situ strategy and lacunary precursor strategy,***_9 shows a typical Keggin-typeopen or half-sandwich configuration.

关键词： configuration expansion sandwich

Enhancing thermoelectric performance of p-type SnTe through manipulating energy band structures and decreasing electronic thermal conductivity

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Rare Metals 2024年第7期43卷 3232-3241页

作者： Xin Qian Hao-Ran Guo Jia-Xin Lyu Bang-Fu Ding Xing-Yuan San Xiao Zhang Jiang-Long Wang Shu-Fang Wang hebei key lab of Optic-Electronic Information and Materials College of Physics Science and TechnologyHebei UniversityBaoding 071002China College of Electron and Information Engineering Hebei UniversityBaoding 071002China Research Institute for Frontier Science Beihang UniversityBeijing100191China

SnTe has received considerable attention as an environmentally friendly alternative to the representative thermoelectric material of ***,excessive hole carrier concentration in SnTe results in an extremely low Seebeck coefficient and high thermal conductivity,which makes it exhibit relatively inferior thermoelectric *** this work,the thermoelectric performance of p-type SnTe is enhanced through regulating its energy band structures and reducing its electronic thermal conductivity by combining Bi doping with CdSe ***,the carrier concentration of SnTe is successfully suppressed via Bi doping,which significantly decreases the electronic thermal ***,the convergence and flattening of the valence bands by alloying CdSe effectively improves the effective mass of SnTe while restraining its carrier ***,a maximum figure of merit(ZT) of~ 0.87 at 823 K and an average ZT of~ 0.51 at 300-823 K have been achieved in Sn_(0.96)Bi_(0.04)Te-5%*** results indicate that decreasing the electronic thermal conductivity is an effective means of improving the performance of thermoelectric materials with a high carrier concentration.

关键词： Thermoelectric materials SnTe Energy band structure Electronic thermal conductivity ZT value

Revolutionary entrapment model of uniformly distributed swarm robots in morphogenetic formation

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Defence technology（防务技术） 2024年第1期31卷 496-509页

作者： Chen Wang Zhaohui Shi Minqiang Gu Weicheng Luo Xiaomin Zhu Zhun Fan Shantou University ShantouGuangdongChina National University of Defense technology ChangshaChina key lab of Digital Signal and Image Processing of Guangdong province China

This study proposes a method for uniformly revolving swarm robots to entrap multiple targets,which is based on a gene regulatory network,an adaptive decision mechanism,and an improved *** the gene regulatory network method,the robots can generate entrapping patterns according to the environmental input,including the positions of the targets and ***,an adaptive decision mechanism is proposed,allowing each robot to choose the most well-adapted capture point on the pattern,based on its *** robots employ an improved Vicsek-model to maneuver to the planned capture point smoothly,without colliding with other robots or *** proposed decision mechanism,combined with the improved Vicsek-model,can form a uniform entrapment shape and create a revolving effect around targets while entrapping *** study also enables swarm robots,with an adaptive pattern formation,to entrap multiple targets in complex *** robots can be deployed in the military field of unmanned aerial vehicles’(UAVs)entrapping multiple *** experiments demonstrate the feasibility and superiority of the proposed gene regulatory network method.

关键词： Swarm intelligence Revolutionary entrapment Flocking Robots Gene regulatory network Vicsek-model Entrapping multiple targets

Vibration harmonic suppression technology for electromagnetic vibrators based on an improved sensorless feedback control method

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Frontiers of Information technology & Electronic Engineering 2024年第3期25卷 472-483页

作者： Wei LI Junning CUI Xingyuan BIAN Limin ZOU Centerof Ultra-precision Optoelectronic Instrument Engineering Harbin Institute of TechnoogyHarbin 0080China key lab of Ultra-precision Intlligent instrumentation(Harbin Institute of technology).Ministry of Industry and Information technology Harbin 150080China

To realize low harmonic distortion of the vibration waveform output from electromagnetic vibrators,we propose a vibration harmonic suppression technology based on an improved sensorless feedback control *** changing the original driving circuit,the alternating current(AC)equivalent resistance of the driving coil is used to obtain high-precision vibration velocity information,and then a simple and reliable velocity feedback control system is *** the study of the effect of different values of key parameters on the system,we have achieved an effective expansion of the velocity characteristic frequency band of low-frequency vibration,resulting in an enhanced harmonic suppression capability of velocity feedback *** present extensive experiments to prove the effectiveness of the proposed method and make comparisons with conventional control *** the frequency range of 0.01-1.00 Hz,without using any sensors,the method proposed in this study can reduce the harmonic distortion of the vibration waveform by about 40%compared to open-loop control and by about 20%compared to a conventional sensorless feedback control method.

关键词： Vibration calibration Electromagnetic vibrators Harmonic suppression Sensorless control method Velocity feedback control

Imide-pillared covalent organic framework protective films as stable zinc ion-conducting interphases for dendrite-free Zn metal anodes

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Journal of Energy Chemistry 2024年第10期97卷 470-477页

作者： Xiaoman Ye Xuemei Xiao Zhijing Wu Xin Wu Lin Gu Sheng Liu School of Chemical Engineering and technology Sun Yat-sen University The key lab of Low-Carbon Chemistry & Energy Conservation of Guangdong province Sun Yat-sen University

The notorious growth of zinc dendrite and the water-induced corrosion of zinc metal anodes（ZMAs）restrict the practical development of aqueous zinc ion batteries（AZIBs）.In this work,a zinc metallized,imide-pillared covalent organic framework（ZPC） protective film has been engineered as a stable Zn2+ion-conducting interphase to modulate interfacial kinetics and suppress side reactions for *** to bare Zn,ZPC@Zn exhibits a higher Zn2+ionic conductivity,a larger Zn2+transference number,a lower electronic conductivity,a smaller desolvation activation energy and correspondingly a significant suppression of corrosion,hydrogen evolution and Zn ***,the ZPC@Zn||ZPC@Zn symmetric cell obtains a cycling lifespan over 3000 h under 5 mA cm-2for 1 mA h *** ZPC@Zn||NH4V4O10coin-type full battery delivers a specific capacity of 195.8 mA h g-1with a retention rate of78.5% at 2 A g-1after 1100 cycles,and the ZPC@Zn||NH4V4O10pouch full cell shows a retention of70.1% in reversible capacity at 3 A g-1after 1100 *** present incorporation of imide-linked covalent organic frameworks in the surface modification of ZMAs will offer fresh perspectives in the search for ideal protective films for the practicality of AZIBs.

关键词： Aqueous zinc ion batteries Covalent organic frameworks Imide linkage Surface modification Zinc metal anodes

Strategies to advance thermoelectric performance of PbSe and PbS materials

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Rare Metals 2024年第9期43卷 4099-4114页

作者： Zheng-Hao Hou Xin Qian Qiu-Juan Cui Shu-Fang Wang Li-Dong Zhao Shijiazhuang key laboratory of Low Carbon Energy Materials College of Chemical EngineeringShijiazhuang University hebei key lab of Optic-Electronic Information and Materials College of Physics Science and Technology Hebei University School of Materials Science and Engineering Beihang University

Thermoelectric materials possess the unique capability to convert thermal energy into electric energy and vice versa, making them promising for waste heat recovery and efficient cooling systems. Currently, extensively investigated thermoelectric materials such as Bi2Te3,PbTe and GeTe exhibit superior thermoelectric properties at room temperature and medium temperature ***, the broad application of these thermoelectric materials has been impeded by the high cost and restricted accessibility of Te and Ge in the earth's crust. Over the past few years, researchers have shown increasing interest in PbSe-and PbS-based materials, primarily attributed to their abundant elemental supply and relatively low costs. The assessment of research progress and a comprehensive overview of optimization strategies in time can significantly contribute to further improving the thermoelectric performance. These strategies include optimizing carrier concentration(aliovalent doping, dynamic doping and defect state), enhancing density-of-state effective mass(band convergence, band flattening and energy filtering effect), optimizing carrier mobility(band sharpening and band alignment) and reducing lattice thermal conductivity(all-scale hierarchical defect structures designing). This systematic summary and analysis provide novel insights and perspectives for the development of thermoelectric materials.

关键词： Carrier concentration

Chemoselective epoxidation of electron-deficient olefins with molecular oxygen via conjugated olefins epoxidation and BHT hydroxylation

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Science China Chemistry 2024年第9期67卷 3012-3018页

作者： Jia Nie Huanfeng Jiang Chuanle Zhu School of Chemistry and Chemical Engineering Key Lab of Functional Molecular Engineering of Guangdong ProvinceSouth China University of TechnologyGuangzhou 510640China Guangdong Provincial key laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing South China University of TechnologyGuangzhou 510640China

The chemoselective epoxidation of electron-deficient olefins in the presence of electron-rich alkene moieties is *** chemoselective epoxidation strategy undergoes a conjugated olefin epoxidation and BHT hydroxylation process to give various useful oxiranes in high yields,especially for the 2-substituted ***,this protocol features mild conditions,is transition-metal free,operationally simple,and gram-scalable,and tolerates diverse functional *** candidate HSD-16 is synthesized smoothly by this *** studies indicate molecular oxygen is the terminal oxidant and the O-source of the oxiranes.

关键词： chemoselective epoxidation alkene fluorine molecular oxygen

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