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Rare Metals 2018年第2期37卷 107-117页

作者： hui-hui Lu chun-Sheng Shi Nai-Qin Zhao En-Zuo Liu chun-Nian He Fang He Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin 300350China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China

Carbon and few-layer MoS2 nanosheets co- modified TiO2 nanocomposites （defined as MoS2-C@TiO2） were prepared through a facile one-step pyrolysis reaction technique. In this unique nanostructure, the TiO2 nanosh- eets with stable structure serve as the backbones, and carbon coating and few-layer MoS2 tightly adhere onto the surface of the TiO2. It needs to be pointed out that the carbon coating improves the overall electronic conductivity and the few-layer MoS2 facilitates the diffusion of lithium ions and offers more active sites for lithium-ion storage. As a result, when evaluated as lithium-ion battery anodes, the MoS2-C@TiO2 nanocomposites exhibit markedly enhanced lithium storage capability compared with pure TiO2. A high specific capacity of 180 mA.h.g-1 has been achieved during the preliminary cycles, and the specific capacity can maintain 160 mA.h.g-1 at a high current density of 1C （1C=167 mA.g-1） even after 300 discharge/ charge cycles, indicating the great potential of the MoS2- C@TiO2 on energy storage.

关键词： Few-layer MoS2 nanosheets Carbon Co-modified TiO2 nanosheets Lithium-ion battery anodes

Steering motion control of a snake robot via a biomimetic approach

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Frontiers of Information Technology & Electronic Engineering 2019年第1期20卷 32-44页

作者： Wenjuan ouyang Wenyu LIANG Chenzui LI hui ZHENG Qinyuan REN Ping LI State Key Laboratory of Industrial Control Technology Zhejiang University Department of Electrical and Computer Engineering National University of Singapore Zhejiang University of Science and Technology

We propose a biomimetic approach for steering motion control of a snake robot. Inspired by a vertebrate biological motor system paradigm, a hierarchical control scheme is adopted. In the control scheme, an artificial central pattern generator(CPG) is employed to generate serpentine locomotion in the robot. This generator outputs the coordinated desired joint angle commands to each lower-level effector controller, while the locomotion can be controlled through CPG modulation by a higher-level motion controller. The motion controller consists of a cerebellar model articulation controller(CMAC) and a proportional-derivative(PD) controller. Because of the fast learning ability of the CMAC, the proposed motion controller can drive the robot to track the desired orientation and adapt to unexpected perturbations. The PD controller is employed to expedite the convergence speed of the motion controller. Finally, both numerical studies and experiments proved that the proposed approach can help the snake robot achieve good tracking performance and adaptability in a varying environment.

关键词： Snake robot Central pattern generator Cerebellar model articulation controller

Enhancing (de)hydrogenation kinetics properties of the Mg/MgH_(2) system by adding ANi_(5)(A=Ce,Nd,Pr,Sm,and Y) alloys via ball milling

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Journal of Rare Earths 2021年第8期39卷 1010-1016页

作者： Wenfang Liao Wenbin Jiang Xu-Sheng Yang hui Wang Liuzhang ouyang Min Zhu Guangdong Provincial Key Laboratory of Advanced Energy Storage Materials School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510641China China-Australia Joint Laboratory for Energy&Environmental Materials Key Laboratory of Fuel Cell Technology of Guangdong ProvinceGuangzhou 510641China Advanced Manufacturing Technology Research Centre Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic UniversityHung HornKowloonHong KongChina Hong Kong Polytechnic University Shenzhen Research Institute Shenzhen 518057China

Magnesium(Mg)-based alloys have already been widely studied as the hydrogen storage materials because of their high reversible hydrogen storage capacity,low cost,light weight,***,the poor de/hydrogenation kinetic properties dramatically hinder the practical *** this work,the MgH_(2)-ANi_(5)(A=Ce,Nd,Pr,Sm,and Y) composites were prepared by a high-energy ball milling *** can effectively refine the particle size thus improving the kinetic *** results reveal that the MgH_(2)-ANi_(5) composites mainly consist of Mg_(2)NiH_(4),MgH_(2) and rare earth(RE) hydride,which will be dehydrogenated to form Mg_(2)Ni,Mg and stable RE hydride ***,the asmilled MgH_(2)-ANi_(5)(A=Ce,Nd,Pr,Sm,and Y) composites with various A-elements can respectively contribute to a reversible hydrogen storage capacity of 6.16 wt%,5.7 wt%,6.21 wt%,6.38 wt%,and 6.5 wt%at a temperature of 300℃,and show much better kinetic properties in comparison to the pure MgH_(2) without any ***-situ formed Mg_(2) Ni and stable RE hydride(such as CeH_(2.73) and YH_(2)) might act as effective catalysts to significantly improve the hydrogen storage properties of MgH_(2).The present work provides a guideline on improving the kinetic properties of the Mg-based hydrogen storage alloys.

关键词： Mg-based hydrogen storage alloy Kinetic properties ANi_(5) Additives Rare earths

Rock characteristics and dynamic fragmentation process of the 2018 Daanshan rockslide in Beijing,China

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Journal of Mountain Science 2023年第2期20卷 448-465页

作者： FAN Tian-zhen AN hui-cong ouyang Chao-jun WANG Dong-po State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China Key laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

This study investigated the failure mechanism associated with the rock mass structure and the dynamic fragmentation process of blocky rocks of the 2018 Daanshan rockslide that occurred on 11 August,*** was found that the initially collapsed rock of this rockslide was partitioned along the unconformity and strata *** analyzed how the unique rock mass structure,coupled with the road cut and the antecedent rainfall,jointly resulted in its *** on the rock types and geological structures,the initial stratified configuration of a discrete element model was setup to reveal the influences of the local *** numerical model was divided into three *** 1 is the basalt of the Nandaling Formation,the normal and shear stiffnesses of the basalt particles are set as 80 MPa and 40 *** 2 and 3 are the sandstones interbedded with mudstone and sandstone of the Shihezi Formation,and the normal and shear stiffnesses of these parts were set as 6 MPa and 10 MPa,*** dynamic process of the rockslide,particularly the rock fragmentation process,was numerically analyzed using a 3D discrete element *** numerical results were compared with real-time videos and field *** results show that the rock fragmentation and the final deposition range match well with the real disaster phenomenon,and the calculation accuracy of the rockslide reaches 82.41%.Moreover,a parameter sensitivity analysis was conducted,and classical uniform models under different bonding forces were established;the stratified model can better restore the true state of the fragmentation,movement,and deposition processes of ***,for complicated rocks with significant differences in lithology,clarifying the rock mass stratigraphy is essential for an accurate reconstruction of the dynamic process of rockslides.

关键词： Discrete element method Rockslide Stratified model Numerical modeling Fragmentation Daanshan rockslide

Multi-source Remote Sensing Image Registration Based on Contourlet Transform and Multiple Feature Fusion

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International Journal of Automation and computing 2019年第5期16卷 575-588页

作者： Huan Liu Gen-Fu Xiao Yun-Lan Tan chun-Juan ouyang College of Electronic and Information Engineering Jinggangshan UniversityJi′an 343009China Key Laboratory of Watershed Ecology and Geographical Environment Monitoring National Administration of SurveyingMapping and Geoinformation(NASG)Ji′an 343009China College of Mechanical and Electronic Jinggangshan UniversityJi′an 343009China

Image registration is an indispensable component in multi-source remote sensing image processing. In this paper, we put forward a remote sensing image registration method by including an improved multi-scale and multi-direction Harris algorithm and a novel compound feature. Multi-scale circle Gaussian combined invariant moments and multi-direction gray level co-occurrence matrix are extracted as features for image matching. The proposed algorithm is evaluated on numerous multi-source remote sensor images with noise and illumination changes. Extensive experimental studies prove that our proposed method is capable of receiving stable and even distribution of key points as well as obtaining robust and accurate correspondence matches. It is a promising scheme in multi-source remote sensing image registration.

关键词： Feature fusion multi-scale circle Gaussian combined invariant moment multi-direction gray level co-occurrence matrix multi-source remote sensing image registration contourlet transform

The Cauchy Boundary Value Problems on Closed Piecewise Smooth Manifolds in C^n

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Acta Mathematica Sinica,English Series 2004年第6期20卷 989-998页

作者： Liang Yu LIN chun hui QIU School of Mathematical Sciences Xiamen University Academy of Mathematics and System Science CAS

Suppose that D is a bounded domain with a piecewise C 1 smooth boundary in C n . Let ? ∈ C 1+α (?D). By using the Hadamard principal value of the higher order singular integral and solid angle coefficient method of points on the boundary, we give the Plemelj formula of the higher order singular integral with the Bochner–Martinelli kernel, which has integral density ?. Moreover, by means of the Plemelj formula and methods of complex partial differential equations, we discuss the corresponding Cauchy boundary value problem with the Bochner–Martinelli kernel on a closed piecewise smooth manifold and obtain its unique branch complex harmonic solution.

关键词： Bochner–Martinelli kernel Hadamard principal value Plemelj formula Boundary value problem

Synthesis of New Ligand 1,2-Bis{di[(R,R)-1,3,2-oxzaphosphlidine]phosphino}ethane with C_2-symmetric Axis and Application in Rh-catalyzed Asymmetric Hydrogenation

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Chemical Research in Chinese Universities 2007年第5期23卷 544-548页

作者： GONG Da-chun ZHOU Hua WEI Ping ouyang Ping-kai College of Chemistry and Life Science China Three Gorges University Yichang 443001 P. R. China College of Life Science and Pharmacy Nanfing University of Technology Nanfing 210009 P. R. China

New ligand 1,2-bis{di[（R,R）-1,3,2-oxzaphosphlidine]phosphino}ethane [（R,R）-BDOPPEs 1,2,3 and 4] with C2-symmetric axis and bearing nitrogen and oxygen were synthesized from readily available optically active amino *** complexes with these ligands were highly enantioselective catalysts for asymmetric hydrogenation of N-benzoyldehydroamino acid derivatives and α-functionalized ketones in 99%*** 98%e.e.,*** new class of（R,R）-BDOPPEs 1,2,3 and 4 gave much more effectivity and enantionselectivity than their corresponding non-C2-asymmetric aminophosphine phosphinite.

关键词： (R, R) -BDOPPE C2-Symmetry Asymmetric catalytic hydrogenation

On-demand data broadcast scheduling based on AHP and GRA methods in wireless broadcast/UMTS integrated systems

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The Journal of China Universities of Posts and Telecommunications 2007年第4期14卷 1-6页

作者： WANG hui LI chun JI Yang Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications)Ministry of Education Wireless Technology Innovation LaboratoryBeijing100876China

The increasing demand for interactive mobile multimedia service is causing the integration of 3rd generation （3G） cellular systems and wireless broadcast systems. The key challenge is to support data dissemination with low response time, request drop rate, and the unfairness of request drop. This article proposes a novel scheduling algorithm called DAG （on-demand scheduling utilizing analytic hierarchy process （AHP） and grey relational analysis （GRA））, which takes multiple factors--waiting time, number of active requests, deadline--into consideration, and models the data scheduling process as a multiple factors＇ decision-making and best option-selecting process. The proposed approach comprises two parts. The first part applies AHP to decide the relative weights of multiple decision factors according to user requests, while the second adopts GRA to rank the data item alternatives through the similarity between each option and the ideal option. Simulation results are presented to demonstrate that DAG performs well in the multiple criterions mentioned above.

关键词： AHP DAG (on-demand scheduling utilizing AHPand GRA) GRA on-demand data broadcast scheduling

Hexagonal warping effect on Majorana zero modes at the ends of superconducting vortex lines in doped strong 3D topological insulators

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Science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 125-134页

作者： Chuang Li Lun-hui Hu Fu-chun Zhang Department of Physics Zhejiang UniversityHangzhou 310027China Kavli Institute for Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China Department of Physics University of CaliforniaSan Diego CA 92093USA CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

In a superconducting topological insulator, a superconducting vortex line can trap a one-dimensional topological band with localized Majorana zero modes at the ends. Here, we study the effect of hexagonal warping and its corresponding symmetry-breaking effect on vortex phase transition. We perform both analytical calculations based on a semiclassical formula and numerical calculations based on full quantum mechanics using the Bogoliubov-de Gennes equation. We find that the hexagonal warping term extends the topological region of the vortex line as the chemical potential changes and leads to MZMs, even in the absence of topological surface states.

关键词： topological insulator topological superconductor vortex phase transition Majorana zero modes hexagonal warping

Localization of ANP-synthesizing cells in rat stomach

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World Journal of Gastroenterology 2006年第35期12卷 5674-5679页

作者： chun-hui Li Li-hui Pan chun-Yu Li Chang-Lin Zhu Wen-Xie Xu Department of Pathology Affiliated Hospital of Chengde Medical College Chengde 067000 Hebei Province China Department of Microbiology and Immunology Chengde Medical College Chengde 067000 Hebei ProvinceChina Department of Surgery Affiliated Hospital for Anus and Intestines Diseases Hospital of Chengde Medical CollegeChengde 067000 Hebei Province China Department of Physiology College of MedicineShanghai Jiaotong University Shanghai 200030 China

AIM: To study the morphological positive expression of antrial natriuretic peptide (ANP)-synthesizing cells and ultrastructural localization and the relationship between ANP-synthesizing cells and microvessel density in the stomach of rats and to analyze the distribution of the three histologically distinct regions of ANP-synthesizing cells. METHODS: Using immunohistochemical techniques, we studied positive expression of ANP-synthesizing cells in rat stomach. A postembedding immunogold microscopy technique was used for ultrastructural localization of ANP-synthesizing cells. Microvessel density in the rat stomach was estimated using tannic acid-ferric chloride (TAFC) method staining. Distribution of ANP-synthesizing cells were studied in different regions of rat stomach histochemically. RESULTS: Positive expression of ANP-synthesizing cells were localized in the gastric mucosa of rats. Localization of ANP-synthesizing cells identified them to be enterochrochromaffin cells (EC) by using a postembedding immunogold electron microscopy technique. EC cells were in the basal third of the cardiac mucosa region. ANP-synthesizing cells existed in different regions of rat stomach and its density was largest in the gastric cardiac region, and the distribution order of ANP-synthesizing cells in density was cardiac region, pyloric region and fundic region in mucosa layer. We have also found a close relationship between ANP-synthesizing cells and microvessel density in gastric mucosa of rats using TAFC staining. CONCLUSION: ANP-synthesizing cells are expressedin the gastric mucosa. EC synthesize ANP. There is a close relationship between ANP-synthesizing cells and microvessel density in gastric mucosa of *** distribution density of ANP-synthesizing cells is largest in the gastric cardiac region.

关键词： Antrial natriuretic peptide-synthesizing cells Microvessel density Close relationship Gastric cardiac region