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Mechanical properties of Mn-doped ZnO nanowires studied by first-principles calculations

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International Journal of Minerals,Metallurgy and Materials 2012年第1期19卷 89-94页

作者： Zhan-jun Gao you-song gu Xue-qiang Wang Yue Zhang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

First-principles calculations were performed to investigate the mechanical properties of ZnO nanowires and to study the doping and size effects. A series of strains were applied to ZnO nanowires in the axial direction and the elastic moduli of ZnO nanowires were obtained from the energy versus strain curves. Pure and Mn-doped ZnO nanowires with three different diameters （1.14, 1.43, and 1.74 nm） were studied. It is found that the elastic moduli of the ZnO nanowires are 146.5, 146.6, and 143.9 GPa, respectively, which are slightly larger than that of the bulk （140.1 GPa）, and they increase as the diameter decreases. The elastic moduli of the Mn-doped ZnO nanowires are 137.6, 141.8, and 141.0 GPa, which are slightly lower than those of the undoped ones by 6.1%, 3.3%, and 2.0%, respectively. The mechanisms of doping and size effect were discussed in terms of chemical bonding and geometry considerations.

关键词： zinc oxide nanowires mechanical properties doping first-principles calculations manganese

Multilevel analysis of the central-peripheral-target organ pathway:contributing to recovery after peripheral nerve injury

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Neural Regeneration Research 2025年第10期20卷 2807-2822页

作者： Xizi song Ruixin Li Xiaolei Chu Qi Li Ruihua Li Qingwen Li Kai-Yu Tong Xiaosong gu Dong Ming Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjinChina Haihe Laboratory of Brain-Machine Interface and Human-Machine Fusion TianjinChina Department of Rehabilitation Tianjin University Tianjin HospitalTianjinChina Department of Hand Microsurgery Tianjin University Tianjin HospitalTianjinChina School of Exercise and Health Tianjin University of SportTianjinChina Department of Biomedical Engineering the Chinese University of Hong KongHong Kong Special Administrative RegionChina

Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and *** on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target *** has led to restrictions on current therapeutic *** this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target *** peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal *** nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury *** damage to target organs can occur,including skeletal muscle atrophy and sensory receptor *** then provide a brief review of the research advances in therapeutic approaches to peripheral nerve *** main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical ***,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ ***,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery.

关键词： central nervous system central peripheral target organ multilevel pathological analysis nerve regeneration peripheral nerve injury peripheral nervous system target organs therapeutic approach

Anisotropic characteristics of granular materials under simple shear

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Journal of Central South University 2013年第8期20卷 2275-2284页

作者： QIAN Jian-gu you Zi-pei HUANG Mao-song Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education (Tongji University) Shanghai 200092 China Department of Geotechnical Engineering Tongji University Shanghai 200092 China

The discrete element method was used to investigate the microscopic characteristics of granular materials under simple shear loading conditions. A series of simple tests on photo-elastic materials were used as a benchmark. With respect to the original experimental observations, average micro-variables such as the shear stress, shear strain and the volumetric dilatancy were extracted to illustrate the performance of the DEM simulation. The change of anisotropic density distributions of contact normals and contact forces was demonstrated during the course of simple shear. On the basis of microscopic characteristics, an analytical approach was further used to explore the macroscopic behaviors involving anisotropic shear strength and anisotropic stress-dilatancy. This results show that under simple shear loading, anisotropic shear strength arises primarily due to the difference between principal directions of the stress and the fabric. In addition, non-coaxiality, referring to the difference between principal directions of the strain rate and the stress, generates less stress-dilatancy. In particular, the anisotropic hardening and anisotropic stress-dilatancy will reduce to the isotropic hardening and the classical Taylor’s stress-dilatancy under proportional loading.

关键词： simple shear discrete element method anisotropy non-coaxiality

Ballistic penetration damages of hybrid plain-woven laminates with carbon,Kevlar and UHMWPE fibers in different stacking sequences

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Defence Technology（防务技术） 2023年第8期26卷 23-38页

作者： Zhi-yong Li you-song Xue Bao-zhong Sun Bo-hong gu Shanghai Frontier Science Research Center for Modern Textiles College of TextilesDonghua UniversityShanghai201620China

Hybrid composite materials combine different fibers in preform and take advantages of different mechanical behaviors for improving ballistic impact damage *** we report ballistic impact damages of plain-woven laminates with different hybrids and stacking *** kinds of hybrid laminates,i.e.,carbon/Kevlar,carbon/ultra-high molecular weight polyethylene(UHMWPE),and UHMWPE/Kevlar,had been prepared and tested in ballistic penetration with fragment simulating projectiles(FSP).The residual velocities of the projectiles and impact damage morphologies of the laminates have been obtained to show impact energy absorptions for the different hybrid schemes.A microstructural model of the hybrid laminates had also been established to show impact damage mechanisms with finite element analysis(FEA).We found that the UHMWPE/Kevlar hybrid laminates with Kevlar layers as the front face have the highest energy absorption capacity,followed by the carbon/Kevlar hybrid laminates with carbon layers as the front *** main damage modes are fiber breakages,matrix crack and interlayer *** ballistic damage evolutions from the FEA results show that the major damage is shear failure for front layers,while tension failure for the back *** expect that the ballistic impact performance could be improved from the different hybrid schemes.

关键词： Hybrid laminates Ballistic impact damages Energy absorption Finite element analysis(FEA)

Rhodium(III)-Catalyzed Atroposelective C-H Indolylization of 1-Aryl Isoquinolines with 3-Indolylphenyliodonium Salts

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Chinese Journal of Chemistry 2023年第20期41卷 2684-2690页

作者： Dong-song Zheng Jun Zheng Qiang Wang Qing gu Shu-Li you Chang-Kung Chuang Institute East China Normal University3663 N.Zhongshan RoadShanghai200062 China New Cornerstone Science Laboratory State Key Laboratory of Organometallic ChemistryShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling LuShanghai200032 China

Rhodium(III)-catalyzed enantioselective C-H indolylization of isoquinolines was *** C-H coupling reactions between 1-aryl isoquinoline derivatives and 3-indolylphenyliodonium salts proceeded smoothly in the presence of a modified chiral cyclopentadienyl-Rh(III)complex,affording a series of axially chiral indolylated biaryl products in excellent yields and enantioselectivity(up to 98%yield and 95%ee).

关键词： Asymmetric catalysis Axially chiral biaryl compounds C-H indolization Cross-coupling Enantioselectivity Rh catalysis

Data-collection system for high-throughput X-ray absorption fine structure measurements

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Nuclear Science and Techniques 2016年第4期27卷 38-45页

作者： Rui-you Lu Qian Gao song-Qi gu Ya-Yun Yang Rui Si Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China University of Chinese Academy of Sciences Beijing 100049 China

A new X-ray absorption fine structure(XAFS)data-collection system based on the Experimental Physics and Industrial Control System software environment has been established at the BL14W1 beamline of the Shanghai Synchrotron Radiation Facility. The system provides for automatic sequential analysis of multiple samples for continuous high-throughput(HT) measurements. Specifically, 8 sample pellets are loaded into an alumina holder,and a high-precision two-dimensional translation stage is programmed to switch these samples automatically for collecting the XAFS spectrum of each sample in *** implement HT measurements via a graphical user interface developed with Control System ***, the successful operation of the HT XAFS system is demonstrated by running experiments on two groups of copper–ceria catalysts, each of which contains 8 different powder samples.

关键词： X射线吸收精细结构数据采集系统结构测量高通量上海同步辐射装置 XAFS谱测量与控制系统粉末样品

Magnesium single-atom catalysts with superbasicity

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Science China Chemistry 2023年第6期66卷 1737-1743页

作者： Xiang-Bin Shao Yao Nian song-song Peng guo-song Zhang Meng-Xuan gu you Han Xiao-Qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Magnesium-related solid bases have long been considered catalysts with weak or medium *** we report the fabrication of Mg single-atom catalysts with superbasicity for the first time.A sublimation-migration-anchoring strategy is employed,in which the Mg net is sublimated,transported by Ar,and trapped by defective graphene(producing Mg_(1)/G).Simulated and experimental results demonstrate that Mg single atoms are anchored on graphene in tetra-coordination,and Mg single atoms cooperating with C atoms give superbasicity,which differs from conventional alkali/alkaline earth metal oxides with basicity originating from O *** new solid base is highly active in the synthesis of dimethyl carbonate through transesterification of ethylene carbonate with methanol,which is usually catalyzed by strong *** turnover frequency value reaches 99.6 h^(-1) on Mg_(1)/G,which is much higher than that of traditional Mg-related counterparts(1.0–5.6 h^(-1))and even superior to that of typical Na and K-related solid superbases(29.8–36.2 h^(-1))under similar conditions.

关键词： solid superbase single Mg atoms heterogeneous catalysts transesterification reaction

Effect of siRNA-mediated knockdown of eIF3c gene on survival of colon cancer cells

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第6期14卷 451-459页

作者： Ning song Yan WANG Xiao-dong gu Zong-you CHEN Liu-bin SHI Department of General Surgery Huashan HospitalFudan University

Eukaryotic initiation factor subunit c(eIF3c) has been identified as an oncogene that is over-expressed in tumor cells and,therefore,is a potential therapeutic target for gene-based cancer *** study was focused on investigating the effect of small interfering RNA(siRNA)-mediated eIF3c gene knockdown on colon cancer cell *** eIF3c gene was observed to be highly expressed in colon cancer cell *** expression levels of the gene in eIF3c siRNA infected and control siRNA infected cells were compared via real-time polymerase chain reaction(PCR) and western blotting *** proliferation levels were analyzed employing 3-(4,5-dimethylthiazol 2-yl)-2,5-diphenyltetrazolium bromide(MTT) and colony formation ***,the effects of eIF3c gene knockdown on the cell cycle and apoptosis were analyzed using flow *** results showed that suppression of eIF3c expression significantly(P<0.001) reduced cell proliferation and colony formation of RKO colon cancer *** cell cycle was arrested by decreasing the number of cells entering S ***,apoptosis was induced as a result of eIF3c ***,eIF3c deletion effectively reduced the survival of colon cancer cells and could be used as a therapeutic tool for colon cancer therapy.

关键词： Eukaryotic initiation factor subunit c(eIF3c) Colon cancer RKO cells Small interfering RNA(siRNA)

Study on effectiveness evaluation of weapon systems based on grey relational analysis and TOPSIS

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Journal of Systems Engineering and Electronics 2009年第1期20卷 106-111页

作者： gu Hui song Bifeng Coll. of Aeronautics Northwestern Polytechnical Univ. Xi'an 710072 P. R. China

To evaluate the effectiveness of weapon systems, the advantages and disadvantages of grey relational analysis and TOPSIS for multiattribute decision-making is pointed out, and an effectiveness evaluation model of weapon systems by combining grey relational analysis and TOPSIS is proposed. The model aggregates the grey relational grade and the distance to a new integrated closeness and reflects not only the trend but also the situation of the alternative. The example illuminates that the model is effective for the effectiveness evaluation of weapon systems.

关键词： multiattribute decision-making effectiveness evaluation grey relational analysis TOPSIS integratedcloseness.