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Journal of Computational Mathematics 2024年第3期42卷 705-734页

作者： tao sun Chengjian Zhang Haiwei sun School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan 430074China Department of Mathematics University of MacaoMacaoChina

This paper deals with numerical methods for solving one-dimensional(1D)and twodimensional(2D)initial-boundary value problems(IBVPs)of space-fractional sine-Gordon equations(SGEs)with distributed *** 1D problems,we construct a kind of oneparameter finite difference(OPFD)*** is shown that,under a suitable condition,the proposed method is convergent with second order accuracy both in time and *** implementation,the preconditioned conjugate gradient(PCG)method with the Strang circulant preconditioner is carried out to improve the computational efficiency of the OPFD *** 2D problems,we develop another kind of OPFD *** such a method,two classes of accelerated schemes are suggested,one is alternative direction implicit(ADI)scheme and the other is ADI-PCG *** particular,we prove that ADI scheme can arrive at second-order accuracy in time and *** some numerical experiments,the computational effectiveness and accuracy of the methods are further ***,for the suggested methods,a numerical comparison in computational efficiency is presented.

关键词： Fractional sine-Gordon equation with distributed delay One-parameter finite difference methods Convergence analysis ADI scheme PCG method

Multi-locomotion transition of tensegrity mobile robot under different terrains

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Science China(Technological Sciences) 2024年第2期67卷 536-557页

作者： YANG Qi LIU XinYu WANG PanFeng SONG YiMin sun tao Key Laboratory of Mechanism Theory and Equipment Design(Tianjin University) Ministry of EducationTianjin UniversityTianjin 300350China

Knowing how to make a multi-locomotion robot achieve locomotion transition under different terrains is a challenging problem,especially for tensegrity robots with multi-locomotion *** this study,a motion planning method for the transition of a multi-locomotion tensegrity robot(hereafter TJUBot)under different terrains is *** robot can achieve four locomotion modes:earthworm-like,inchworm-like,tumbling,and sliding locomotion with only two *** models of the four locomotion modes under five typical terrains,including flat ground,confined space,obstacle,gap,and descending slope,are established using the energy ***,the kinematic characteristics(driving law and initial position)of the robot under these terrains are *** this basis,motion planning for the locomotion transition of TJUBot is conducted,which includes a perception strategy based on three laser sensors and a transition strategy under different *** driving laws of the two motors that can ensure the effective locomotion transition of TJUBot under different terrains are naturally ***,experiments are *** demonstrate that the robot can achieve effective locomotion transition when the motion planning method is used.

关键词： multi-locomotion robot tensegrity kinematic modeling locomotion transition

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S-scheme regulated Ni_(2)P-NiS/twinned Mn_(0.5)Cd_(0.5)S hetero-homojunctions for efficient photocatalytic H_(2)evolution

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Journal of Materials Science & Technology 2024年第2期169卷 148-157页

作者： Qiqi Zhang Zhen Wang Yuhang Song Jun Fan tao sun Enzhou Liu School of Chemical Engineering/Xi’an Key Laboratory of Special Energy Materials Northwest UniversityXi’an 710069China

Effective bulk phase and surface charge separation is critical for charge utilization during the photo-catalytic energy conversion *** this work,the ternary Ni_(2)P-NiS/twinned Mn_(0.5)Cd_(0.5)S(T-MCS)nanohybrids were successfully constructed via combining Ni_(2)P-NiS with T-MCS solid solution for visible light photocatalytic H_(2)evolution.T-MCS is composed of zinc blende Mn_(0.5)Cd_(0.5)S(ZB-MCS)and wurtzite Mn_(0.5)Cd_(0.5)S(WZ-MCS)and those two alternatively arranged crystal phases endow T-MCS with excellent bulk phase charge separation performance for the slight energy level difference between ZB-MCS and WZ-MCS.S-scheme carriers transfer route between NiS and T-MCS can accelerate the interfacial charge separation and retain the active electrons and holes,meanwhile,co-catalyst Ni_(2)P as electron receiver and proton reduction center can further optimize the H_(2)evolution reaction kinetics based on the surface Schottky barrier *** above-formed homo-heterojunctions can establish multiple charge transfer channels in the bulk phase of T-MCS and interface of T-MCS and Ni_(2)*** the synergistic effect of twinned homojunction,S-scheme heterojunction,and Schottky barrier,the ternary Ni_(2)P-NiS/T-MCS com-posite manifested an H_(2)production rate of 122.5 mmol h^(-1)g^(-1),which was 1.33,1.24,and 2.58 times higher than those of the NiS/T-MCS(92.4 mmol h^(-1)g^(-1)),Ni_(2)P/T-MCS(98.4 mmol h^(-1)g^(-1)),and T-MCS(47.5 mmol h^(-1)g^(-1)),*** work demonstrates a promising strategy to develop efficient sul-fides photocatalyst toward targeted solar-driven H_(2)evolution through homo-heterojunction engineering.

关键词： Photocatalytic H_(2)evolution Twinned Mn_(0.5)Cd_(0.5)S Homojunction S-scheme heterojunction Schottky barrier

Enhanced Strength-Ductility Synergy in Submerged Friction Stir Processing ER2319 Alloy Manufactured by Wire-Arc Additive Manufacturing via Creating Ultrafine Microstructure

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 793-807页

作者： Jinpeng Hu tao sun Fujun Cao Yifu Shen Zhiyuan Yang Chan Guo College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics(NUAA)Nanjing 210016China

Submerged friction stir processing(SFSP)with flowing water was employed to alleviate the porosities and coarse-grained structure introduced by wire-arc *** a result,uniform and ultrafine grained(UFG)structure with average grain size of 0.83μm was achieved with the help of sharply reduced heat input and holding time at elevated *** optimized UFG structure enabled a superior combination of strength and ductility with high ultimate tensile strength and elongation of 273.17 MPa and 15.39%.Specifically,grain refinement strengthening and decentralized θ(Al_(2)Cu)phase in the sample subjected to SFSP made great contributions to the enhanced *** addition,the decrease in residual stresses and removal of pores substantially enhance the *** rates of cooling and low temperature cycling,which are facilitated by the water-cooling environment throughout the machining process,are vital in obtaining superior *** work provides a new method for developing a uniform and UFG structure with excellent mechanical properties.

关键词： Submerged friction stir processing Wire-arc additive manufacturing Al-Cu alloy Residual stress Strengthening and toughening mechanism Ultrafine grained microstructure

Passivation remediation of weakly alkaline Cd-contaminated soils using combined treatments of biochar and sepiolite

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Ecological Processes 2024年第1期13卷 40-52页

作者： Yuxin Zhang Shan Gao Hongtao Jia tao sun Shunan Zheng Shihang Wu Yuebing sun Key Laboratory of Original AgroEnvironmental Pollution Prevention and Control Ministry of Agriculture and Rural Affairs (MARA)/Tianjin Key Laboratory of Agro-Environment and Agro-Product Safety Agro–Environmental Protection InstituteMARA College of Resources and Environment Sciences Xinjiang Agricultural University Rural Energy and Environment Agency Ministry of Agriculture and Rural Affairs

Background Cadmium(Cd) pollution in agricultural soils has become a priority environmental concern globally. A reasonable application of passivators is critical to address the problem. In this study, we examined the remediation effects of rice husk biochar(r BC) and sepiolite(Sep) as single and combined(r BC + Sep) treatments on Cd pollution in a weakly alkaline soil using three maize cultivars(Liyu 16, Zhengdan 958, and Sanbei 218) as test crops. We also explained the mechanisms involved in the remediation *** The pseudo-second-order kinetic equation and Langmuir model could well describe the adsorption process of r BC + Sep for Cd2+. Compared with the control treatment(CK), soil available Cd concentration decreased by 29.51–36.34% under r BC + Sep treatment(p 0.05).Conclusions The application of 0.2% r BC + 0.5% Sep composite passivation material to weakly alkaline Cd-contaminated soil can effectively reduce the Cd concentration of soil and maize.

关键词： Cd Rice husk biochar Sepiolite Passivation restoration Weakly alkaline soil Maize

Formation behaviors of rod-like reactive shaped charge penetrator and their effects on damage capability

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Defence Technology（防务技术） 2024年第2期32卷 242-253页

作者： tao sun Haifu Wang Shipeng Wang Chao Ge Die Hu Pengwan Chen Yuanfeng Zheng Beijing Institute of Technology State Key Laboratory of Explosion Science and TechnologyBeijing100081China Xi'an Institute of Electromechanical Information Technology Xi'an710065China

Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical *** pulsed X-ray technology and a spaced aluminum/steel plate with the thicknesses of 5 mm/100 mm are *** types of sphericalsegment aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with Cu contents of 0%,46.6%,and 66%are fabricated and *** experimental results show that the reactive liners can form excellent rod-shaped penetrators with tail skirts under the shaped charge effect,but the tail skirts disappear over ***,rupturing damage to the aluminum plate and penetration to the steel plate are caused by the RRSCP *** simulation analysis,the RRSCP is formed by a mechanically and chemically coupled response with the reactive liner activated by shock in its outer walls and bottom and then backward overturning,forming a leading reactive penetrator and a following chemical energy *** unique formation structure determines the damage modes of the aluminum plate and the steel *** analysis indicates that the formation behaviors and damage capability of Al-PTFE-Cu RRSCP strongly depend on Cu *** increasing Cu content,the velocity,activation extent,and reaction extent of Al-PTFE-Cu RRSCP decrease,which contribute to elongation and alleviate the negative effects of chemical reactions on elongation,significantly increasing the length-diameter ratio and thus enhancing the capability of steel plate ***,the lower activation extent and energetic density will weaken the RRSCP's capability of causing rupturing damage to the aluminum plate.

关键词： Reactive materials Al-PTFE composites Reactive liner X-ray Penetration

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General Minimum Lower-order Confounding Split-plot Designs with Important Subplot Factors

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Acta Mathematicae Applicatae Sinica 2024年

作者： tao sun Shengli ZHAO School of Statistics and Data Science Qufu Normal University

In this paper, we consider the regular s-level fractional factorial split-plot(FFSP) designs when the subplot(SP) factors are more important. The idea of general minimum lower-order confounding criterion is applied to such designs, and the general minimum lower-order confounding criterion of type SP(SP-GMC) is proposed. Using a finite projective geometric formulation, we derive explicit formulae connecting the key terms for the criterion with the complementary set. These results are applied to choose optimal FFSP designs under the SP-GMC criterion. Some two-and three-level SP-GMC FFSP designs are constructed.

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Advanced nano-based strategies for mRNA tumor vaccine

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Acta Pharmaceutica Sinica B 2024年第1期14卷 170-189页

作者： Yangqi Qu Jingjing Xu Tong Zhang Qinjun Chen tao sun Chen Jiang Key Laboratory of Smart Drug Delivery(Ministry of Education) Minhang HospitalState Key Laboratory of Medical NeurobiologyDepartment of PharmaceuticsSchool of PharmacyFudan UniversityShanghai 201203China

Tumor vaccine is a promising strategy for cancer immunotherapy by introducing tumor antigens into the body to activate specific anti-tumor immune *** with the technological breakthroughs in genetic engineering and delivery systems,messenger ribonucleic acid(mRNA)technology has achieved unprecedented development and application over the last few years,especially the emergency use authorizations of two mRNA vaccines during the COVID-19 pandemic,which has saved countless lives and makes the world witness the powerful efficacy of mRNA technology in ***,unlike infectious disease vaccines,which mainly induce humoral immunity,tumor vaccines also need to activate potent cellular immunity to control tumor growth,which creates a higher demand for mRNA delivery to the lymphatic organs and antigen-presenting cells(APCs).Here we review the existing bottlenecks of mRNA tumor vaccines and advanced nano-based strategies to overcome those challenges,as well as future considerations of mRNA tumor vaccines and their delivery systems.

关键词： mRNA vaccine Nanoparticle Tumor vaccine Delivery system Stability Targeting Transfection Immunogenicity

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Interpenetrating network-reinforced gel polymer electrolyte for ultra-stable lithium−iodine batteries

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Carbon Energy 2024年第6期6卷 234-247页

作者： Ying Jiang Peng Huang Minman Tong Bingxin Qi tao sun Zhongyun Xian Wen Yan Chao Lai School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhouJiangsuChina

Li-I_(2) batteries have attracted much interest due to their high capacity,exceptional rate performance,and low *** so,the problems of unstable Li anode/electrolyte interface and severe polyiodide shuttle in Li-I_(2) batteries need to be ***,the interfacial reactions on the Li anode and I_(2) cathode have been effectively optimized by employing a well-designed gel polymer electrolyte strengthened by cross-linked Ti-O/Si-O(GPETS).The interpenetrating network-reinforced GPETS with high ionic conductivity(1.88×10^(-3)S cm^(-1)at 25℃)and high mechanical strength endows uniform Li deposition/stripping over 1800 h(at 1.0mA cm^(-2),with a plating capacity of 3.0mAh cm^(-2)).Moreover,the GPETS abundant in surface hydroxyls is capable of capturing soluble polyiodides at the interface and accelerating their conversion kinetics,thus synergistically mitigating the shuttle *** from these properties,the use of GPETS results in a high capacity of 207 mAh g^(-1)(1 C)and an ultra-low fading rate of 0.013%per cycle over 2000 cycles(5 C).The current study provides new insights into advanced electrolytes for Li-I_(2) batteries.

关键词： electrode/electrolyte interface gel polymer electrolytes lithium dendrites lithium−iodine batteries polyiodide shuttle

Notably Accelerated Nano-Bainite Transformation via Increasing Undissolved Carbides Content on GCr15Si1Mo Bearing Steel

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 703-712页

作者： Yan-Hui Wang Hua-Qiang sun Wen-Jing Feng Lei-Jie Zhao Xiang Chen Qing-An Chen Hai-tao sun Jian-Jun Wang Zhi-Nan Yang Key Laboratory of Intelligent Industrial Equipment Technology of Hebei Province School of Mechanical and Equipment EngineeringHebei University of EngineeringHandan056038China Collaborative Innovation Center for Modern Equipment Manufacturing of Jinan New Area Hebei University of EngineeringHandan056038China School of Materials Science and Engineering Tsinghua UniversityBeijing100084China Avic Shang da Superalloys Company Limited Xingtai054800China National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004China

In this study, a high-carbon nano-bainitic GCr15Si1Mo bearing steel was investigated. Specifically, the effects of content and size of undissolved carbides on the microstructure and transformation kinetics of nano-bainite were analyzed. The results demonstrated that after prolonged austempering at low temperatures, the mixed microstructure composed of nano-bainite (NB), undissolved carbides (UC), and retained austenite (RA) was obtained in GCr15SiMo steel. When the experimental steel was austenitized at 900 ℃, the undissolved carbides gradually dissolved until reaching a stable state with increasing holding time. Furthermore, at the same austempering temperature, despite different volume fractions of undissolved carbides in the substrate, the volume fractions of nano-bainite in the final microstructures remained essentially the same. Moreover, the higher the content of undissolved carbides in steel, the faster the transformation rate of nano-bainite and the shorter the total transformation time.

关键词： Nano-bainite Undissolved carbides Bainitic transformation kinetics Carbon concentration