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中国有色金属学会会刊：英文版 2007年第1期17卷 214-219页

作者：甘永平黄辉张文魁 college of Chemical engineering and Materials Science Zhejiang University of Technology

Electrochemical codeposition and electrocatalytic properties of platinum and molybdenum oxide nanoparticles(Pt-MoOx) on carbon-nanotubes/graphite electrode for methanol oxidation were *** micrograph and elemental composition of the resulting Pt-MoOx/CNTs/graphite electrode were characterized by scanning electron microscopy(SEM)and energy dispersive X-ray spectroscopy(EDS).The results show that the Pt-MoOx particles with the average size of about 50 nm are highly dispersed on the CNTs *** Pt-MoOx/CNTs/graphite electrode delivers excellent electrocatalytic properties for methanol *** highest mass activity(Am)reaches 264.8 A/g at the loading mass of 159.3μg/*** may be attributed to the small particle size and high dispersion of Pt-MoOx catalysts deposited on the CNTs *** kinetic analysis from electrochemical impedance spectroscopy(EIS)reveals that the existed MoOx phase can improve the chemisorptive and catalytic properties for methanol oxidation.

关键词：甲醇氧化反应碳管燃料电池单化学

Effect of Longitudinal Magnetic Field on Vibration Response of Double-Walled Carbon Nanotubes Embedded in Viscoelastic Medium

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Acta Mechanica Solida Sinica 2018年第2期31卷 187-206页

作者： Dapeng Zhang Yongjun Lei Zhibin Shen college of Aerospace Science and engineering National University of Defense Technology

This paper aims to study the effect of externally applied longitudinal magnetic field on the transverse vibration of viscoelastic double-walled carbon nanotubes （visco-DWCNTs） embedded in a viscoelastic medium. The analyses are carried out based on the nonlocal viscoelastic model and Euler-Bernoulli beam theory. Governing equations are derived for the vibration of the embedded visco-DWCNT subjected to a magnetic field, where the Lorentz magnetic force, the surrounding viscoelastic medium, the intertube van der Waals forces and viscoelasticity of the DWCNT are taken into consideration. In this study, the transfer function method is employed to solve the governing equations, which enables one to obtain the natural frequencies and the corresponding mode shapes in closed form for the DWCNTs with arbitrary boundary conditions. Here the developed mechanics model is first compared with the existing techniques available in the literature in a few particular cases, where excellent agreement is achieved. The validation of the model is followed by a detailed parametric study of the effects of longitudinal magnetic field, nonlocal parameter, boundary conditions, structural damping coefficient and aspect ratio of the DWCNTs on their vibration. The study demonstrates the efficiency of the present technique designed for vibration analysis of a complicated multi-physics system comprising DWCNTs, the viscoelastic medium and a magnetic field in longitudinal direction.

关键词： Carbon nanotubes Nonlocal continuum theory Free vibration Magnetic field Viscoelastic medium

Instantaneous and time-averaged flow structures around a blunt double-cone with or without supersonic film cooling visualized via nano-tracer planar laser scattering

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Chinese Physics B 2013年第1期22卷 368-373页

作者：朱杨柱易仕和何霖田立丰周勇为 college of Aerospace Science and engineering National University of Defense Technology

In a Mach 3.8 wind tunnel, both instantaneous and time-averaged flow structures of different scales around a blunt double-cone with or without supersonic film cooling were visualized via nano-tracer planar laser scattering （NPLS）, which has a high spatiotemporal resolution. Three experimental cases with different injection mass flux rates were carried out. Many typical flow structures were clearly shown, such as shock waves, expansion fans, shear layers, mixing layers, and turbulent boundary layers. The analysis of two NPLS images with an interval of 5 us revealed the temporal evolution characteristics of flow structures. With matched pressures, the laminar length of the mixing layer was longer than that in the case with a larger mass flux rate, but the full covered region was shorter. Structures like K-H （Kelvin-Helmholtz） vortices were clearly seen in both flows. Without injection, the flow was similar to the supersonic flow over a backward- facing step, and the structures were relatively simpler, and there was a longer laminar region. Large scale structures such as hairpin vortices were visualized. In addition, the results were compared in part with the schlieren images captured by others under similar conditions.

关键词： blunt cone supersonic flow structure flow visualization supersonic film cooling

A thin radar-infrared stealth-compatible structure:Design,fabrication,and characterization

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Chinese Physics B 2014年第2期23卷 333-338页

作者：田浩刘海韬程海峰 Science and technology on Advanced Ceramic Fibers and Composites Laboratory College of Aerospace Science and EngineeringNational University of Defense Technology Science and technology on Scramjet Laboratory College of Aerospace Science and EngineeringNational University of Defense Technology

A thin radar-infrared stealth-compatible structure with reflectivity below -10 dB in the whole radar X wave band and infrared emissivity less than 0.3 in the infrared region of 8μm-14 μm is reported. The designed stealth-compatible structure consists of metallic frequency selective surface （MFSS）, resistive frequency selective surface （RFSS）, and metal backing from the top down, and it is only 2. l-mm thick. The MFSS is made up of some divided low infrared emissivity metal copper films, and the RFSS consists of a capacitive array of square resistive patches. They are placed close together, working as an admittance sheet because of a mutual influence between them, and the equivalent admittance sheet greatly reduces the thickness of the whole structure. The proposed stealth-compatible structure is verified both by simulations and by experimental results. These results indicate that our proposed stealth-compatible structure has potential applications in stealth fields.

关键词： radar-infrared stealth-compatible structure absorbing property infrared emissivity

Modeling of a space flexible probe–cone docking system based on the Kane method

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Chinese Journal of Aeronautics 2014年第2期27卷 248-258页

作者： Zhang Xiang Huang Yiyong Chen Xiaoqian Han Wei college of Aerospace Science and engineering National University of Defense Technology

Recent developments in micro- and nano-satellites have attracted the interest of the research community worldwide. Many colleges and corporations have launched their satellites in space. Meanwhile, the space flexible probe-cone docking system for micro- and nano-satellites has become an attractive topic. In this paper, a dynamic model of a space flexible probe-cone dock- ing system, in which the flexible beam technology is applied, is built based on the Kane method. The curves of impact force versus time are obtained by the Lagrange model, the Kane model, and the experimental method. The Lagrange model was presented in the reference and verified by both finite element simulation and experiment. The results of the three methods show good agreements on the condition that the beam flexibility and the initial relative velocity change. It is worth mentioning that the introduction of vectorial mechanics and analytical mechanics in the Kane method leads to a large reduction of differential operations and makes the modeling process much easier than that of the Lagrange method. Moreover, the influences of the beam flexibility and the initial relative velocity are discussed. It is concluded that the initial relative velocity of space docking operation should be controlled to a certain value in order to protect the docking system.

关键词： Dynamic models Flexible structures Impact testing Kane method Space probe-cone docking

Effects of Doping CeO_2,Er_2O_3 on Properties of TiO_2-SiO_2 Ceramics for Catalyst Supporter of deNO_x

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Journal of Rare Earths 2006年第Z2期24卷 234-238页

作者：祝社民沈岳松李伟峰刘亚云 college of Material Science and engineering Nanjing University of Technology college of Life Science and Pharmacy Nanjing University of Technology

Effects of doping CeO2 and Er2O3 on the mechanical strength, thermal expansion coefficient, sintering temperature of TiO2-SiO2 ceramics were investigated. The experimental results and the microscopic analysis of SEM, XRD, TG-DSC, FT-IR and TEM show that adding CeO2 and Er2O3 into TiO2-SiO2 ceramics can prohibit the growth of its crystal grains, make their size uniform and form them into a dense structure, which finally enhance its mechanical behaviors, and the lower thermal expansion coefficient that leads to an excellent property of thermal shock resistance. After the reforming TiO2-SiO2 ceramics doped by CeO2 was sintered at 1380℃, the bending strength reached to 83 MPa, and the thermal expansion coefficient was 9.8×10-6/℃within the temperature range of 25 ~ 800℃, which provides a promising basis of making equipped honeycomb catalyst of deNOx.

关键词： erbium oxide cerium oxide ceramics of TiO2-SiO2 deNOx bending strength thermal expansion rare earths

Microstructure in the Semi-solid State and Mechanical Properties of AZ80 Magnesium Alloy Reheated from the As-cast and Extruded States

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Acta Metallurgica Sinica(English Letters) 2013年第4期26卷 473-482页

作者： Wenyong JIANG Tian CHEN Liping WANG Yicheng FENG Yan ZHU Kaifeng WANG Jiapeng LUO Shouwei ZHANG college of Materials Science and engineering Harbin University of Science and Technology

The multi-axial forging （MAF） process was introduced into the strain induced metal activation （SIMA） process to replace conventional forging. Microstructure evolution of MAF formed AZ80 magnesium alloy during partial remelting was investigated. Furthermore, the tensile mechanical properties for AZ80 magnesium alloy thixoextruded from the starting materials treated by MAF were determined. For comparison, as-cast AZ80 magnesium alloy was also thixoextruded. The results show that the SIMA route produced ideal, fine semi-solid microstructure, in which almost completely spheroidal primary solid grains had a little amount of entrapped liquid. The microstructure of the as-cast alloy in the semi-solid state is less spheroidized compared with the MAF alloy under the similar isothermal holding conditions. With prolonged holding time, the size of the solid grain increases and the degree of spheroidization is improved in the MAF formed alloys. However, the solid grain size of the as-cast alloys decreases initially, and then increases with further increasing temperature. The tensile mechanical properties for AZ80 magnesium alloy thixoextruded from the starting material produced by MAF are better than those of AZ80 magnesium alloy thixoextruded from the starting material produced by casting. The ultimate tensile strength, yield strength and elongation of the alloy thixoextruded from the starting material produced by MAF are 314 MPa, 238 MPa and 14%, respectively.

关键词： Magnesium alloy Microstructure Mechanical properties Partial remelting

Degradation of anthraquinone dyes by ozone

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中国有色金属学会会刊：英文版 2007年第4期17卷 880-886页

作者：刘佳乐罗汉金韦朝海 college of Environmental Science and engineering South China University of Technology

The decolorization of three kinds of anthraquinone dyes by ozone was investigated and the residues in the degradation solution were analyzed. The results indicate that the decolorizing effects are obvious with the decolorization efficiency of dyes all above 96% in 40 min. The pH value and TOC concentration decline while the conductivity increases with the lapse of reaction time. The complicated dye molecules are decomposed to simple compounds with —SO3H, —Cl in the dye molecules transformed into SO2-4 ,Cl-, and nitrogen partially degrades into NO 3-according to the bases of different groups. The organic acids are found in the degradation solutions and dyes with larger relative molecular mass are decomposed into substances with larger relative molecular mass.

关键词：废水处理脱色蒽醌染料臭氧

Method for electromagnetic detection satellites scheduling based on genetic algorithm with alterable penalty coefficient

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Journal of Systems engineering and Electronics 2014年第5期25卷 822-832页

作者： Jun Li Hao Chen Zhinong Zhong Ning Jing Jiangjiang Wu college of Electronic Science and engineering National University of Defense Technology

The electromagnetic detection satellite （EDS） is a type of earth observation satellites （EOSs）. The Information collected by EDSs plays an important role in some fields, such as industry, science and military. The scheduling of EDSs is a complex combinatorial optimization problem. Current research mainly focuses on the scheduling of imaging satellites and SAR satellites, but little work has been done on the scheduling of EDSs for its specific characteristics. A multi-satellite scheduling model is established, in which the specific constrains of EDSs are considered, then a scheduling algorithm based on the genetic algorithm （GA） is proposed. To deal with the specific constrains of EDSs, a penalty function method is introduced. However, it is hard to determine the appropriate penalty coefficient in the penalty function. Therefore, an adaptive adjustment mechanism of the penalty coefficient is designed to solve the problem, as well as improve the scheduling results. Experimental results are used to demonstrate the correctness and practicability of the proposed scheduling algorithm.

关键词： electromagnetic detection satellite (EDS) scheduling genetic algorithm (GA) constraint handling penalty function method alterable penalty coefficient.

Correction:Anti-lymphangiogenesis for boosting drug accumulation in tumors

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Signal Transduction and Targeted Therapy 2024年第7期9卷 3141-3142页

作者： Chunling Wang Junchao Xu Xiaoyu Cheng Ge Sun Fenfen Li Guangjun Nie Yinlong Zhang CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China Sino-Danish college University of Chinese Academy of Sciences Beijing 100190 China Sino-Danish Center for Education and Research Beijing 100190 China Department of Bioengineering University of Pennsylvania Philadelphia PA 19104 USA School of Nanoscience and engineering University of Chinese Academy of Sciences Beijing 100049 China

Correction to:Signal Transduction and Targeted Therapy https://***/10.1038/s41392-024-01794-4,published online 15 April 2024 After the article was published online,1 the authors noticed one inadvertent mistake in Supplementary *** image of lung H&E in the Lip-Dox group was repeatedly inserted as the image of Dox group by mistake during the preparation of the *** correct figure was provided as *** correction did not affect any of our results or discussion presented in the original *** apologize for this inadvertent *** original article has been corrected.

关键词： lung boosting repeatedly