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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1089-1097页

作者： Jianjun Xu Hanlin ding xin Lin Feng Liu Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The microstructure characteristics and strengthening mechanism of Inconel738LC(IN-738LC) alloy prepared by using induction-assisted directed energy deposition(IDED) were elucidated through the investigation of samples subjected to IDED under 1050℃ preheating with and without hot isostatic pressing(HIP,1190℃,105 MPa,and 3 h).Results show that the as-deposited sample mainly consisted of epitaxial columnar crystals and inhomogeneously distributed γ’ phases in interdendritic and dendritic core *** HIP,grain morphology changed negligibly,whereas the size of the γ’ phase became increasingly *** further heat treatment(HT,1070℃,2 h + 845℃,24 h),the γ’ phase in the as-deposited and HIPed samples presented a bimodal size distribution,whereas that in the as-deposited sample showed a size that remained *** comparison of tensile properties revealed that the tensile strength and uniform elongation of the HIP + HTed sample increased by 5% and 46%,respectively,due to the synergistic deformation of bimodal γ’phases,especially large cubic γ’ ***,the relationship between phase transformations and plastic deformations in the IDEDed sample was discussed on the basis of generalized stability theory in terms of the trade-off between thermodynamics and kinetics.

关键词： directed energy deposition Ni-based superalloys high-temperature preheating hot isostatic pressing microstructure tensile properties

Adjacent mode resonance of a hydraulic pipe system consisting of parallel pipes coupled at middle points

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Applied Mathematics and Mechanics(English Edition) 2023年第3期44卷 363-380页

作者： xin FAN Changan ZHU Xiaoye MAO Hu ding Department of Precision Machinery and Precision Instruments University of Science and Technology of ChinaHefei 230022China State-owned Machinery Factory in Wuhu Wuhu 241007Anhui ProvinceChina Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China

The coupling vibration of a hydraulic pipe system consisting of two pipes is *** pipes are installed in parallel and fixed at their ends,and are restrained by clips to one bracket at their middle *** pipe subjected to the basement excitation at the left end is named as the active pipe,while the pipe without excitation is called the passive *** clips between the two pipes are the bridge for the vibration *** adjacent natural frequencies will enhance the vibration *** governing equation of the coupled system is deduced by the generalized Hamilton principle,and is discretized to the modal *** modal correction is used during the *** investigation on the natural characters indicates that the adjacent natural frequencies can be adjusted by the stiffness of the two clips and *** harmonic balance method(HBM)is used to study the responses in the adjacent natural frequency *** results show that the vibration energy transmits from the active pipe to the passive pipe swimmingly via the clips together with a flexible bracket,while the locations of them are not node *** adjacent natural frequencies may arouse wide resonance curves with two peaks for both *** stiffness of the clip and bracket can release the vibration *** is suggested that the stiffness of the clip on the passive pipe should be weak and the bracket should be strong *** this way,the vibration energy is reflected by the almost rigid bracket,and is hard to transfer to the passive pipe via a soft *** best choice is to set the clips at the pipe node *** current work gives some suggestions for weakening the coupled vibration during the dynamic design of a coupled hydraulic pipe system.

关键词： hydraulic pipe system coupling vibration adjacent mode coupling parallel pipe conveying fluid harmonic balance method(HBM)

Interception time and uncertainty optimization for tangent-impulse orbit interception problem

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Defence Technology（防务技术） 2022年第3期18卷 418-440页

作者： Yang Hong Li xin-hong ding Wen-zhev Department of Aerospace Science and Technology Space Engineering UniversityNo.1 BaYi RoadHuaiRou DistrictBeijing101416China

The traditional tangent impulse interception problem does not consider the influence of actual ***,by taking the actual state deviation of the interceptor into the orbit design process,an interception orbit that is more robust than the nominal orbit can be ***,we study the minimum time interception problem and the minimum terminal interception error problem under tangent impulse conditions and give an orbit optimization method that considers the interception time and the interception ***,we express the interceptor's transfer time equation as a form of flight path angle,establish a global optimization model for solving the minimum time tangent impulse interception and give a hybrid optimization algorithm based on Augmented Lagrange Genetic Algorithm-Sequential Quadratic Programming(ALGA-SQP).Secondly,we use the universal time equation and Bootstrap resampling technology to calculate the interceptor's terminal error distribution and establish the relevant global optimization model by using the circumscribed cuboid volume of the interceptor's terminal position error ellipsoid as the optimization ***,we combined the above two singleobjective optimization models to establish a global multi-objective optimization model that considers interception time and interception uncertainty and gave a hybrid multi-objective optimization algorithm based on Non-dominated Sorting Genetic Algorithm Ⅱ-Goal Achievement Method(NSGA2-GAM).The simulation example verifies the effectiveness of this method.

关键词： Tangent impulse interception Minimum time Interception uncertainty Multi-objective optimization Hybrid optimization

Broadband Terahertz Transmission Modulation Based on Hybrid Graphene-Metal Metamaterial

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Journal of Electronic Science and Technology 2018年第2期16卷 98-104页

作者： Lan-Ju liang Zhang Zhang xin Yan xin ding De-Quan Wei Qi-Li Yang Zhen-Hua Li Jian-Quan Yao College of Precision Instrument and Opto-Electronics Engineering Tianjin UniversityTianjin 300072 School of Opto-Electronic Engineering Zaozhuang UniversityZaozhuang 277160

A novel patterned metamaterial,composed of graphene layer and metal periodic array of split ring resonators （SRRs） and cross-shapedresonators （CSRs）, with broadband terahertz （THz） wave modulation was proposed and theoretically studied. It demonstrated that a broad passband high transmission of over 96.1% in the frequency range from 1.02 THz to 1.66 THz and two narrow band resonance frequencies f1 and f2 could be generated. The modulation depth of transmission was 29.2% when the graphene layer was covered on the metal metamaterial surface, and the modulation depth could be further increased by increasing the Fermi energy of graphene layer and reached approximately 79.5% at 1.0 eV in a broadband THz frequency range. The resonance frequencies of f1 and f2 were blue-shifted, and their modulation depths reached about 63.2% and 18%, respectively. These results show that the ultrathin graphene-metal metamaterial exhibits potential to achieve highperformance active THz devices and may offer widespread applications.

关键词： Graphene metamaterial modulator terahertz

ON POTENT ELEMENTS AND PSEUDO CLEAN RINGS

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数学杂志 2025年第1期45卷 39-47页

作者： ding Yan GAO Han-peng LIU xin-yi YAN Zi-yi ZHANG Ting School of Mathematical Sciences Anhui UniversityHefei 230601China

In this paper,potent index of an element and pseudo clean rings are *** properties and examples of pseudo clean rings are *** also show that Zm is pseudo clean for every 2≤m∈Z and pseudo clean rings are ***,we prove... 详细信息

关键词： clean rings strongly J-clean rings pseudo clean rings potent elements

xingnao Kaiqiao needling method for acute ischemic stroke： a meta-analysis of safety and efficacy

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Neural Regeneration Research 2017年第8期12卷 1308-1314页

作者： Zhi-xin Yang Jia-hong Xie ding-ding Liu Department of Traditional Chinese Medicine Chengde Medical University Chengde Hebei Province China Key Laboratory of Traditional Chinese Medicine Research and Development Institute of Traditional Chinese Medicine Chengde Medical University Chengde Hebei Province China School of Traditional Chinese Medicine North China University of Science and Technology Tangshan Hebei Province China

OBJECTIVE： To evaluate the effectiveness and safety of the xingnao Kaiqiao needling method for treating acute ischemic *** SOURCES： We retrieved relevant randomized controlled trials involving xingnao Kaiqiao acupuncture for treatment of acute ischemic stroke. The China National Knowledge Infrastructure, Weipu Information Resources System, Wanfang Medical Data System, Chinese Biomedical Literature Database, Cochrane Library, and Pub Med were searched from June 2006 to March *** SELECTION： We analyzed randomized and semi-randomized clinical controlled trials that compared xingnao Kaiqiao acupuncture with various control treatments, such as conventional drugs or other acupuncture therapies, for treatment of acute ischemic stroke. The quality of articles was evaluated according to the Cochrane Handbook for Systematic Reviews of Interventions（Version 5.1）, and the study was carried out using Cochrane system assessment methods. Rev Man 5.2 was used for the meta-analysis of the included *** MEASURES： The mortality rate, disability rate, activities of daily living（Barthel Index）, and clinical efficacy were ***： Twelve studies met the inclusion criteria for this review. The meta-analysis showed that between xingnao Kaiqiao acupuncture and the control treatment, xingnao Kaiqiao acupuncture reduced the disability rate [risk ratio（RR） = 0.51, 95% confidence interval（CI） = 0.27-0.98, z = 2.03, P 〈 0.05], elevated the activities of daily living（weighted mean difference = 12.23, 95% CI： 3.66-20.08, z = 2.80, P 〈 0.005）, and had greater clinical efficacy（RR = 1.61, 95% CI： 1.23-2.09, z = 3.53, P 〈 0.0004）. However, there was no significant difference in mortality rate（RR = 0.61, 95% CI： 0.15-2.45, z = 0.70, P 〉 0.05）. CONCLUSION： The xingnao Kaiqiao needling method is effective and safe for acute ischemic stroke. However, there was selective bias in this study, and the likelihood of measurement bias is high. Thus, more high-quality randomized

关键词： nerve regeneration xingnao Kaiqiao needling method acute ischemic stroke meta-analysis systematic review activities of daily living Barthel index mortality disability rate clinical e^cacy neuralregeneration

Precedence-constrained path planning of messenger UAV for air-ground coordination

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Control Theory and Technology 2019年第1期17卷 13-23页

作者： Yulong ding Bin xin Jie CHEN School of Automation Beijing Institute of Technology Beijing 700087 China Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing Institute of Technology Beijing 100081 China Beijing Advanced Innovation Center for Intelligent Robots and Systems Beijing Institute of Technology Beijing 100081 China

This paper addresses an unmanned aerial vehicle (UAV) path planning problem for a team of cooperating heterogeneous vehicles composed of one UAV and multiple unmanned ground vehicles (UGVs). The UGVs are used as mobile actuators and scattered in a large area. To achieve multi-UGV communication and collaboration, the UAV serves as a messenger to fly over all task points to collect the task information and then flies all UGVs to transmit the information about tasks and UGVs. The path planning of messenger UAV is formulated as a precedence-constrained dynamic Dubins traveling salesman problem with neighborhood (PDDTSPN). The goal of this problem is to find the shortest route enabling the UAV to fly over all task points and deliver information to all requested UGVs. When solving this path planning problem, a decoupling strategy is proposed to sequentially and rapidly determine the access sequence in which the UAV visits task points and UGVs as well as the access location of UAV in the com mu nication n eighborhood of each task point and each UGV. The effectiveness of the proposed approach is corroborated through computational experiments on randomly generated instances. The computational results on both small and large in stances dem on strate that the proposed approach can generate high-quality solutions in a reasonable time as compared with two other heuristic algorithms.

关键词： Air-ground coordination curvature-constrained path planningz precedence constraints Dubins traveling salesman problem

Quantum Codes from Constacyclic Codes over Polynomial Residue Rings

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Chinese Journal of Electronics 2019年第6期28卷 1131-1138页

作者： ding Jian LI Hongju liang Jing TANG Yongsheng College of Mathematics and Informatics Fujian Normal University Fujian Provincial Key Lab of Network Security and Cryptology Fujian Normal University Department of General Education Anhui Xinhua University School of Mathematics and Statistics Hefei Normal University

Sufficient and necessary conditions for Hermitian（1 + λu）-constacyclic self-orthogonal codes over F;m +uF;m are obtained, where λ is a unit of F;m +uF;*** on this, a new method for the construction of p;ary quantum codes from the obtained Hermitian（1 + λu）-constacyclic self-orthogonal codes over F;m +uF;m is *** an example, [[p;-1, p;-2d + 1, d]];m quantum MDS codes are constructed for 1 ≤ d ≤（p;+ 1）/2 and p ≠ 2, as well as some other quantum codes.

关键词： Quantum code Quantum MDS code Constacyclic code Self-orthogonal code

Computing Ground State Solution of Bose-Einstein Condensates Trapped in One-Dimensional Harmonic Potential

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Communications in Theoretical Physics 2006年第5X期46卷 873-878页

作者： YUAN Qing-xin ding Guo-Hui Department of Mathematics and Physics Zhengzhou Institute of Aeronautical Industry Management Zhengzhou 450015 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

For Bose-Einstein condensates trapped in a harmonic potential well, we present numerical results from solving the tlme-dependent nonlinear Schrolinger equation based on the Crank-Nicolson method. With this method we are able to find the ground state wave function and energy by evolving the trial initial wave function in real and imaginary time spaces, respectively. In real time space, the results are in agreement with [Phys. Rev. A 51 （1995） 4704], but the trial wave function is restricted in a very small range. On the contrary, in imaginary time space, the trial wave function can be chosen widely, moreover, the results are stable.

关键词： Bose-Einstein condensates nonlinear Schrodinger equation Crank-Nicolson method

Recent advances in the electrochemistry of layered post-transition metal chalcogenide nanomaterials for hydrogen evolution reaction

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Journal of Energy Chemistry 2021年第9期30卷 451-479页

作者： Yong Wang Yang Zhao Xiang ding liang Qiao School of Physics University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina

Layered two-dimensional(2 D)materials have received tremendous attention due to their unique physical and chemical properties when downsized to single or few *** types of layered materials,especially transition metal dichalcogenides(TMDs)have been demonstrated to be good electrode materials due to their interesting physical and chemical *** from TMDs,post-transition metal chalcogenides(PTMCs)recently have emerged as a family of important semiconducting materials for electrochemical *** are layered materials which are composed of post-transition metals raging from main group IIIA to group VA(Ga,In,Ge,Sn,Sb and Bi)and group VI chalcogen atoms(S,selenium(Se)and tellurium(Te)).Although a large number of literatures have reviewed the electrochemical and electrocatalytic applications of TMDs,less attention has been focused on *** this review,we focus our attention on PTMCs with the aim to provide a summary to describe their fundamental electrochemical properties and electrocatalytic activity towards hydrogen evolution reaction(HER).The characteristic chemical compositions and crystal structures of PTMCs are firstly discussed,which are different from ***,inherent electrochemistry of PTMCs is discussed to unveil the well-defined redox behaviors of PTMCs,which could potentially affect their efficiency when applied as electrode ***,we focus our attention on electrocatalytic activity of PTMCs towards HER including novel synthetic strategies developed for the optimization of their HER *** review ends with the perspectives for the future research direction in the field of PTMC based electrocatalysts.

关键词： Post-transition metal chalcogenide Layered material Chemical composition Crystal structure Inherent electrochemistry Hydrogen evolution