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调控串联三金属AuAgCu异质结上*CO中间体的吸附构型,促进CO2通过不对称C-C耦合电还原为乙醇（英文）

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Science China Materials 2025年第1期 173-179页

作者：石永霞李俊俊闵志雯王鑫亿侯曼马昊庄泽超秦毓辰孙源淼王定胜张志成 Key Laboratory of Organic Integrated Circuit Ministry of Education & Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of Chemistry School of Science Tianjin University Faculty of Materials Science and Energy Engineering/institute of technology for Carbon Neutrality Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Department of Chemistry Tsinghua University College of Sciences Henan Agricultural University

在电化学CO2还原反应中,合理调节关键中间体*CO的吸附构型可以促进碳-碳（C–C）偶联生成多碳产物.在这项工作中,理论计算表明,通过顶式吸附的*CHO和三重位吸附的*CO在Cu位点上进行C–C耦合是一种能量有利的途径.作为概念验证,制备了串...

在电化学CO2还原反应中,合理调节关键中间体*CO的吸附构型可以促进碳-碳（C–C）偶联生成多碳产物.在这项工作中,理论计算表明,通过顶式吸附的*CHO和三重位吸附的*CO在Cu位点上进行C–C耦合是一种能量有利的途径.作为概念验证,制备了串联三金属AuAgCu异质结（Au@Ag/Cu）,其中Au@Ag位点上顶式吸附的*CO溢流到Cu位点后转变为三重位吸附,然后该三重位吸附的*CO和Cu位点上顶式吸附的*CHO进行不对称C–C偶联,促进了乙醇产物的形成.在-0.3 V ***的低电位下,乙醇法拉第效率最高为65.9%.我们的工作通过调节中间产物的吸附构型,为串联催化的内在机制提供了新的见解.

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Preparation of TiAl alloy powder by high-energy ball milling and diffusion reaction at low temperature

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Rare Metals 2018年第1期37卷 21-25页

作者： Hui-Ping Shao Zhi Wang Tao Lin Qing Ye Zhi-Meng Guo institute for advanced Material and technology University of Science and Technology Beijing

In this paper, TiAl alloy powders were prepared successfully by high-energy ball milling and diffusion reaction in vacuum at low temperature. The titanium powder, aluminum powder, and titanium hydride powder were used as raw materials. The samples were characterized by scanning electron microscopy（SEM）, X-ray diffraction（XRD）, field-emission scanning electron microscopy（FESEM）, and differential thermal analysis（DTA）. The results show that the alloy powders with the main intermetallic compounds of TiAl are obtained using Ti-Al powders and TiH2-Al powders after heated for 2 h at 500 ℃,3 h at 600 ℃,and 3 h at 750 ℃,*** average grain sizes of alloy powder are about 45 and20 μm with irregular shape, respectively. The prepared TiAl alloy powders are relatively pure, and the average quality content of oxygen in the alloy powders is0.33 wt%. The forming process of alloy powder contains both the diffusion reaction of Ti and Al,which gives priority to the diffusion reaction of aluminum.

关键词： High-energy ball milling Titanium hydride powder Titanium powder TiAl alloy powder Diffusion reaction

Microstructural evolution and mechanical properties of in situ TiB_2/Al composites under high-intensity ultrasound

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Rare Metals 2015年第3期34卷 168-172页

作者： Cun-Guang Chen Ji Luo Zhi-Meng Guo Wei-Wei Yang Jun Chen institute of advanced Materials and technology University of Science and Technology Beijing

Microstructural evolution and mechanical properties of in situ TiB2/A1 composites fabricated with exothermic reaction process under high-intensity ultra- sound produced by the magnetostrictive transducer were investigated. In this method, the microstructure and grain refining performance of the TiB2/A1 composites were characterized by optical morphology （OM）, scanning electron microscopy （SEM）, energy-dispersive spec- trometer （EDS）, and X-ray diffraction （XRD） analysis. Microstructural observations show a decreasing trend in the grain size of the composites due to the ultrasound and the content of TiB2 particles in the composites. Compared with the process without ultrasound, the morphology and ag- glomeration of TiB2 particles are improved by high-in- tensity ultrasound. Meanwhile, it is proposed that the formation of TiBz particles occurs via the transformation from TiA13, and at the optimal amount of the reactants, the conversion efficiency of TiA13 into TiB2 almost reaches up to 100 %. Finally, the effects of high-intensity ultrasound and TiB2 particles on the mechanical properties of the TiB2/A1 composites were also discussed.

关键词： Microstructural evolution Mechanicalproperties In situ High-intensity ultrasound Magnetostrictive transducer

Near-net shape processing of spherical high Nb-TiAl alloy powder by gelcasting

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International Journal of Minerals,Metallurgy and Materials 2013年第11期20卷 1076-1080页

作者： Hui-ping Shao Xiao-ting Liu Ye Ji Zhi-meng Guo institute for advanced Material & technology University of Science and Technology Beijing

Spherical Ti-45A1-8.5Nb-（W,B,Y） alloy powder prepared by an argon plasma process was near-net shape by gelcasting. In the non-aqueous system, methaerylate-2-hydroxy ethyl, toluene, benzoyl peroxide, and N,N-dimethylaniline were used as the monomer, solvent, initiator, and catalyst, respectively. To improve sintering and forming behaviors, many additives were included in the suspension. The concentrated suspension with a solid loading of 70vo1% was prepared. The high Nb-TiA1 powder was analyzed by electron microscopy and X-ray diffraction. It was found that the green bodies had a smooth surface and homogeneous microstructure, exhibiting a bending strength as high as 50 MPa. After sintering at 1480℃ for 2 h in vacuum, uniform complex-shaped high Nb-TiA1 parts were successfully produced.

关键词： titanium aluminum alloys niobium alloys powders gelcasting microstructure

Fabrication and mechanical properties of high-performance aluminum alloy

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Rare Metals 2014年第4期33卷 400-403页

作者： Wei-Wei Yang Zhi-Meng Guo Hui-Qin Cao Ji Luo An-Ping Ye institute of advanced Materials and technology University of Science and Technology Beijing

High-performance Al-Cu-Mg alloy was fabri- cated by high-energy ball milling, sintering, and hot extrusion. The microstructure and mechanical properties of the material were preliminarily investigated. Results show that the formation of liquid phase during sintering pro- motes the densification of the aluminum powders. A 97.1% theoretical density is achieved in this alloy after sintering. The material shows excellent mechanical prop- erties after extrusion and heat treatment. The ultimate tensile strength and yield strength of the extruded samples with heat treatment are 613 and 465 MPa, respectively.

关键词： Aluminum alloys Ball mill Sintering Extrusion Mechanical properties

Tunable wettability of metallic films with assistance of porous anodic aluminum oxide

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Frontiers of Optoelectronics 2010年第3期3卷 317-320页

作者： Dongdong LI Chuanhai JIANG Jiankun ZHOU Xin REN Division of Energy and Environmental Research Shanghai Advanced Research Institute Chinese Academy of Sciences School of Material Science and Engineering Shanghai Jiao Tong University advanced technology institute Technology Center of Baosteel

The present work demonstrates a simple method to prepare nanostructured Ni films with different morphologies with the assistance of porous anodic aluminum oxide(AAO) membranes. A great distinction is observed as the Ni films deposited onto the top and bottom sides of AAO membranes. The wetting properties of as-prepared membranes are investigated by measuring the contact angles of water on the surfaces. Results show that the static water contact angle changes dramatically from 124°±1° to 45°±1° on different Ni films, implying a change of the wettability from hydrophobicity to hydrophilicity affected by the surface patterns. This versatile approach can be conducted on various materials with potential applications in a broad range of fields.

关键词： wettability anodic aluminum oxide (AAO) Ni film

Entropy generation analysis of natural convective radiative second grade nanofluid flow between parallel plates in a porous medium

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Applied Mathematics and Mechanics(English Edition) 2019年第4期40卷 481-498页

作者： K.RAMESH O.OJJELA Department of Applied Mathematics Defence Institute of Advanced Technology

The present article explores the entropy generation of radiating viscoelastic second grade nanofluid in a porous channel confined between two parallel plates. The boundaries of the plates are maintained at distinct temperatures and concentrations while the fluid is being sucked and injected periodically through upper and lower plates. The buoyancy forces, thermophoresis and Brownian motion are also considered due to the temperature and concentration differences across the channel. The system of governing partial differential equations has been transferred into a system of ordinary differential equations(ODEs) by appropriate similarity relations, and a shooting method with the fourth-order Runge-Kutta scheme is used for the solutions. The results are analyzed in detail for dimensionless velocity components. The temperature, concentration distributions, the entropy generation number, and the Bejan number corresponding to various fluid and geometric parameters are shown graphically. The skin friction, heat and mass transfer rates are presented in the form of tables. It is noticed that the temperature profile of the fluid is enhanced with the Brownian motion, whereas the concentration profile of the fluid is decreased with the thermophoresis parameter, and the entropy and Bejan numbers exhibit the opposite trend for the suction and injection ratio.

关键词： nanofluid thermophoresis Brownian motion shooting method thermal radiation

Lightweight quasi-layered elastic fibrous porous ceramics with high compressive stress and low thermal conductivity

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Journal of Materials Science & technology 2023年第12期143卷 207-215页

作者： Ning Zhou Baosheng Xu Zhiliang Zhou Lijie Qu Yiguang Wang Wenbo Han Daining Fang National Key Laboratory of Science and technology for National Defense on advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150001China institute of advanced Structure technology Beijing Institute of TechnologyBeijing 100081China

Fibrous porous ceramics are attractive for use as thermal insulation ***,the intrinsic brit-tleness of rigid materials has remained challenging and severely restricts their ***,we demonstrated a facile method for fabricating elastic fibrous porous ceramics(EFPCs)with high com-pressive strength and low thermal conductivity through ordinary press filtration and subsequent heat *** quasi-layered structure and the well-bonded bridging fibers between layers are the key points for the elasticity of *** advanced EFPCs exhibited low density(∼0.126 g cm^(−3)),high com-pressive stress(∼0.356 MPa),and low thermal conductivity(∼0.026 W m^(−1) K^(−1)).Compared with rigid porous fibrous materials,the EFPCs had deformability and excellent shape *** contrast to flexible materials,the EFPCs possessed high compressive stress,thus endowing them with good resistance to *** emergence of this fascinating material may provide new insights for candidate materials in thermal insulation and other fields.

关键词： Silica fiber Facile press filtration Elastic fibrous porous ceramics High compressive stress Thermal insulation

The Reduced Space Method for Calculating the Periodic Solution of Nonlinear Systems

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Computer Modeling in Engineering & Sciences 2018年第5期115卷 233-262页

作者： Haitao Liao institute of advanced structure technology Beijing institute of technologyBeijing 100081China

A hybrid method combined the reduced Sequential Quadratic Programming(SQP)method with the harmonic balance method has been developed to analyze the characteristics of mode localization and internal resonance of nonlinear bladed *** the aid of harmonic balance method,the nonlinear equality constraints for the constrained optimization problem are *** reduced SQP method is then utilized to deal with the original constrained optimization *** the null space decomposition technique to the harmonic balance algebraic equations results in the vanishing of the nonlinear equality constraints and a simple optimization problem involving only upper and lower bound constraints on the optimization variables is formed and ***,numerical results are given for several test examples to validity the proposed *** efficiency of the solution method to trace the family of energy dependent nonlinear modes is *** localization nonlinear normal modes of bladed disks related to various types of internal resonances are explored.

关键词： Nonlinear normal modes internal resonances reduced SQP method harmonic balance method