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RESEARCH AND DEVELOPMENT OF HIgH TEMPERATURESTRUCTURAL MATERIALS FOR AERO-ENgINE APPLICATIONS

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 443-452页

作者： g. q. Zhang Beijing Institute of Aeronautical Materials （BIAM） Beijing 100095 China

The status of research, development of superalloys and materials processing ＆ fabrication technologies for aero-engine applications in China Aviation Industry, with an emphasis on recent achievements at BIAM including directionally solidified and single crystal superalloys for blade and vane applications, wrought superqlloys for aero-engine disks and rings, and powder metalurgy （PM） superalloys for high performance disk applications were described. It was also reviewed the development of new class of high temperature structural materials, such as structural intermetallics, and advanced material processing technologies including rapid solidification, spray forming and so on. The trends of research and development of the above mentioned superalloys and processing technologies are outlined. Cast, wrought and PM superalloys are the workhorse materials for the hot section of current aero-engines. New high temperature materials and advanced processing technologies have been and will be the subject of study. It is speculated that high performance, high purity and low cost superalloys and technologies will play key roles in aero-engines.

关键词： superalloy intermetallic materials processing aero-engine application

Experimental demonstration of 220-gHz terahertz signals wireless transmission over 4.6 km

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Science China(Information Sciences) 2025年第1期68卷 386-388页

作者： Yi WEI Jianjun YU Mingxu WANg Xiongwei YANg qiutong ZHANg Jingwen TAN Bing ZHANg Ying WU Yang HAN Peng TIAN Wen ZHOU Kaihui WANg Feng zhao State Key Laboratory of ASIC and System Key Laboratory for Information Science of Electromagnetic Waves (MoE)School of Information Science and Technology Fudan University School of Electronic Engineering Xi'an University of Posts and Telecommunications

The advancement of terahertz (THz) communication technology drives the evolution of wireless communication systems,offering novel pathways and technical means for the development of future 6g communication *** wireless communication systems are often constrained by bandwidth limitations of electronic devices in high frequency ***,THz communication technology leverages the characteristics of electromagnetic waves to transcend these limitations,enabling communication athigher frequencies and wider bandwidths.

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Magnetization reversal of antiferromagnetically coupled perpendicular anisotropy films driven by current

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Journal of Materials Science & Technology 2018年第5期34卷 832-835页

作者： X.T.zhao Y.q.zhao W.Liu Z.M.Dai T.T.Wang X.g.zhao Z.D.Zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

By inserting an ultrathin Pt layer at Co/Ru interface,we established antiferromagnetic coupling with outof-plane magnetization in Co/Ru/Co film stacks fabricated by *** achieve configuration suitable for free layer,the magnetic properties of the stacks have been investigated by changing the thickness of Co,Ru and Pt layers using an orthogonal wedges *** is found that magnetic properties for upper Co layer thinner than 0.5 nm are sensitive to little change in Ru *** continuity of upper Co layer by slightly increasing the thickness can effectively increase the squareness of minor *** switching magnetization of synthetic antiferromagnetic（SAF） structure is achieved by DC current under an in-plane static magnetic field of ± 500 *** structure is very promising for free layer in spintronic application.

关键词： Magnetic materials Multilayer structure Wedge Exchange coupling Antiferromagnetic

Mechanical properties of cocoons constructed consecutively by a single silkworm caterpillar,Bombyx mori

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Acta Mechanica Sinica 2008年第2期24卷 151-160页

作者： S.q.Huang H.P.zhao X.q.Feng W.Cui Z.Lin M.q.Xu Department of Engineering Mechanics FML Tsinghua University Beijing 100084 China Department of Sericulture Shandong Agriculture University Tai'an 271018 China Department of Landscape Architecture Human Environment-Biological Polytechnic College. Hengyang 421005 China

Most animals have the ability to adapt, to some extends and in different ways, the variation or disturbance of environment. In our experiments, we forced a silkworm caterpillar to spin two, three or four thin cocoons by taking it out from the cocoon being constructed. The mechanical properties of these cocoons were studied by static tensile tests and dynamic mechanical thermal analysis. Though external disturbances may cause the decrease in the total weight of silk spun by the silkworm, a gradual enhancement was interestingly found in the mechanical properties of these thin cocoons. Scanning electron microscopy observations of the fractured specimens of the cocoons showed that there exist several different energy dissipation mechanisms occurred simultaneously at macro-, meso-, and micro-scales, yielding a superior capacity of cocoons to adsorb the energy of possible attacks from the outside and to protect efficiently its pupa against damage. Through evolution of millions of years, therefore, the silkworm Bombyx mori seems to have gained the ability to adapt external disturbances and to redesign a new cocoon with optimized protective function when its first cocoon has been damaged for some reasons.

关键词： Silk Silkworm cocoon Mechanical property Biomimetics

Local PM_(10) and PM_(2.5) emission inventories from agricultural tillage and harvest in northeastern China

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Journal of Environmental Sciences 2017年第7期29卷 15-23页

作者： Weiwei Chen Daniel q Tong Shichun Zhang Xuelei Zhang Hongmei zhao Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of Sciences Cooperative Institute for Climate & Satellites University of Maryland Center for Spatial Information Science and Systems George Mason University

Mineral particles or particulate matters（PMs） emitted during agricultural activities are major recurring sources of atmospheric aerosol ***,precise PM inventory from agricultural tillage and harvest in agricultural regions is challenged by infrequent local emission factor（EF） *** understand PM emissions from these practices in northeastern China,we measured EFs of PM_（10） and PM_（2.5） from three field operations（i.e.,tilling,planting and harvesting） in major crop production（i.e.,corn and soybean）,using portable real-time PM analyzers and weather station ***-level PM_（10） and PM_（2.5） emissions from agricultural tillage and harvest were estimated,based on local EFs,crop areas and crop *** EFs averaged（107 ± 27）,（17 ± 5） and 26 mg/m^2 for field tilling,planting and harvesting under relatively dry conditions（i.e.,soil moisture 〈15%）,*** EFs of PM from field tillage and planting operations were negatively affected by topsoil *** magnitude of PM_（10） and PM_（2.5） emissions from these three activities were estimated to be 35.1 and 9.8 kilotons/yr in northeastern China,respectively,of which Heilongjiang Province accounted for approximately45%.Spatiotemporal distribution showed that most PM_（10） emission occurred in April,May and October and were concentrated in the central regions of the northeastern plain,which is dominated by dryland *** work is needed to estimate the contribution of agricultural dust emissions to regional air quality in northeastern China.

关键词： PM Emission factor Agricultural inventory Tillage Harvest Burning

Construction of hollow mesoporous silica nanoreactors for enhanced photo-oxidations over Au-Pt catalysts

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National Science Review 2020年第11期7卷 1647-1655页

作者： Hao Tian Jinhui zhao Xinyao Wang Lizhuo Wang Hao Liu guoxiu Wang Jun Huang Jian Liu g.q.(Max) Lu State Key Laboratory of Catalysis Dalian Institute of Chemical Physics (DICP)Chinese Academy of Sciences Centre for Clean Energy Technology School of Mathematical and Physical SciencesFaculty of ScienceUniversity of Technology Sydney Laboratory for Catalysis Engineering School of Chemical and Biomolecular Engineering Sydney Nano Institute The University of Sydney DICP-Surrey Joint Centre for Future Materials Department of Chemical and Process Engineering and Advanced Technology Institute University of Surrey University of Surrey

It is highly desirable to design hollow structures with multi-scale functions by mimicking cells for the construction of micro/nanoreactors. Herein, we report the construction of hollow-structured submicrometer-photoreactors with bimetallic catalysts loaded within mesoporous silicas. The synthesis parameters are optimized to study the evolution of hollow structure through hydrothermal treatment and an ‘adhesive-contraction’ formation mechanism is proposed. Au Pt@HMZS catalysts exhibited a broader absorbance region under visible light and the adsorption edge displayed a red-shift, indicating the strong metal–metal interactions at the alloy interface. The reaction performance of the coupled Au-Pt catalysts can be tuned to achieve excellent catalytic activity in cinnamyl alcohol oxidation to cinnamic acid for 3.1 mmol g-1with 99%selectivity. The proposed strategy to build hollow structures as multifunctional micro/nanoreactors is promising for the design of high-performance and sustainable catalysts for chemical synthesis.

关键词： nanoreactors photocatalytic oxidation metal nanoparticles mesoporous materials surface plasmonic resonance

A brief review：experimental investigation of zonal flows and geodesic acoustic modes in fusion plasmas

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Plasma Science and Technology 2018年第9期20卷 72-84页

作者： K J zhao J q DONg J q LI L W YAN Southwestern Institution of Physics Chengdu 610041People＇s Republic of China

Zonal flows self-generated by turbulence play an important role in regulating turbulence,reducing transport level,and thus improve plasma confinement in fusion *** zonal flows and geodesic acoustic modes have been identified in various *** related issues,such as the poloidal and toroidal symmetries,coupling to turbulence,effects on turbulence and transport,nonlinear energy transfer between turbulence and zonal flows,dependence of the plasma parameters,roles in the confinement regime transitions etc are overviewed briefly in this *** interaction between zonal flows and magnetic islands is emphasized.

关键词： zona flow tokamak turbulence fusion plasma

On the mechanism of Si-promoted destabilization of TiC_(x)particles in Al alloys

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Journal of Materials Science & Technology 2023年第34期165卷 17-26页

作者： H.Dong Y.C.guo Y.Z.Chen F.Xia q.q.guo q.Chen g.L.Li J.Y.zhao Y.Zhong J.P.Li School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an 710021China State Key Lab.of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China School of Science Xi’an University of Science and TechnologyXi’an 710054China

TiC_(x)is an excellent composite strengthening particle and grain refiner for Al ***,the stability of TiC_(x)is poor when solute Si exists in Al alloy melts,which significantly depresses its strengthening and grain refining *** this work,the destabilization mechanisms of the TiC_(x)particles in Al-Si alloy melt with a composition of Al-7Si-7.5TiC were explored via experiments,first-principles calculations and thermodynamic *** experimental results show that Si atoms diffuse into TiC_(x)and Ti atoms are released into the Al melt to form a Ti-rich transition zone during the insulation of TiC_(x)in Al-Si melt,and the TiAlySiz and Al_(4)C_(3)phases are solidified in the Ti-rich zone and at Ti-rich zone/TiC_(x)interface,*** first principles calculations show that the low formation energy of C vacancies facilitates the rapid diffusion of Si atoms in TiC_(x),while the doping of Si atoms reduces the energy barrier of diffusion of Ti atoms in TiC_(x)and promotes the formation of Ti-rich *** thermodynamic calculations show that the wide crystallization temperature range of the destabilized product TiAlySiz phase is the key to continuous decomposition of TiC_(x)*** addition,the driving force of the main destabilization reaction of TiC_(x)in the Al-Si alloys is about 44 times higher than that in the Al alloys without Si *** indicates that the presence of solute Si remarkably promotes the subsequent decomposition process of TiC_(x)in the Al-Si alloy melts.

关键词： Al-Si alloy TiC_(x)particles Destabilization First principles calculations Thermodynamics

Nanomaterials for Clean Air, Energy and Water

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Progress in Natural Science:Materials International 2018年第2期28卷 97-98页

作者： g.q.(Max) Lu University of Surrey

In the last decade,environmental pressures due to air and water pollution and the drive for clean energy supply are rising,which have led to the tremendous interest and investment in sustainable materials *** has been at the forefront of research and development of clean technologies for air,water and energy not surprisingly because of the strong need for such technologies to balance development and

关键词： Energy and Water Nanomaterials for Clean Air