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EFFECTS OF COPPER ION IMPLANTATION ON ANTIBACTERIAL ACTIVITY OF AISI420 STAINLESS STEEL

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Acta Metallurgica Sinica(English Letters) 2005年第2期18卷 153-158页

作者： Z.G.Dan H.W.Ni B.F.Xu j.xiong P.Y.xiong SchoolofMaterialandMetallurgy WuhanUniversityofScienceandTechnologyWuhan430081China SchoolofMedicineScience WuhanUniversityofScienceandTechnologyWuhan430081China

Antibacterial activity of AISI420 stainless steel (SS) implanted by copper was investigated. Ions extracted from a metal vapor vacuum arc (MEVVA) are sourced with 100keV energy and a dose range from 0.2×1017 to 2.0×1017ions·cm-2. The saturation dose of Cu implantation in AISI420 SS and Cu surface concentration were calculated at the energy of 100keV. The effect of dose on the antibacterial activity was analyzed. Results of antibacterial test show that the saturation dose is the optimum implantation dose for best antibacterial activity, which is above 99% against both Escherichia coli and Staphylococcus aureus. Novel phases such as Fe4Cu3 and Cu9.9Fe0.1 were found in the implanted layer by glancing angle X-ray diffraction (GXRD). The antibacterial activity of AISI420 SS attributes to Cu-contained phase.

关键词： antibacterial stainless steel copper ion implantation saturation dose Cu-contained phase

Fabrication and Mechanical Behaviour of Fibre Reinforced Composite Truss Core Sandwich Structures

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Fabrication and Mechanical Behaviour of Fibre Reinforced Com...

The 16th Annual Conference of Hong Kong Society of Theoretical and Applied Mechanics 2012、The 1st Mainland-Hong Kong Youth Forum on Mechanics 2012、The 8th Shanghai-Hong Kong Forum on Mechanics and Its Application 2012

作者： L.Ma j.xiong L.Z.Wu Center for Composite Materials Harbin Institute of Technology

Sandwich structures are widely used in lightweight construction especially in aerospace industries because of their high specific strength and *** sandwich structures with aluminium alloy foam,various honeycombs and lattice truss are being developed for structures that require high strength and blast ***,sandwich structures fabricated by carbon fibre reinforced composite have been proved to be high strength with low density,their lightweight attributes have been revealed,as well as their potential for *** progress has been made recently in manufacturing methods and understanding the structural behaviour of carbon fibre reinforced composite sandwich *** this context,sandwich structures made from carbon fibre reinforced composite truss core provide new opportunities for lightweight,high strength structural *** materials properties and geometrical parameters of composite truss core sandwich structures will be designed for enhance its specific strength and *** moulding hot-press technique for manufacture of carbon fibre composite truss core sandwich structures will be *** this method all the continuous fibres of composite are aligned in the direction of struts and thus the truss structure can fully exploit the intrinsic strength of the fibre reinforced composite. Analytical and experimental investigation will be carried out to explore the mechanical response of carbon fibre composite truss core sandwich *** failure mechanisms of such sandwich structure will be also considered in this study.

关键词： Sandwich Fabrication and Mechanical Behaviour of Fibre Reinforced Composite Truss Core Sandwich Structures

A global morphology of gravity wave activity in the stratosphere revealed by the 8-year SABER/TIMED data

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A global morphology of gravity wave activity in the stratosp...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Y.Zhang j.xiong L.Liu W.Wan Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences Graduate University Chinese Academy of Sciences

[1]From 8 years’ SABER/TIMED temperature profiles between january 2002 and December 2009,we studied the activity of gravity waves in the stratosphere globally. Global distribution of stratospheric gravity wave potential energy was calculated from the temperature *** comparison of gravity wave potential energy Ep shows

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A simulation study for the couplings between DE3 tide and longitudinal WN4 structure in the thermosphere and ionosphere

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A simulation study for the couplings between DE3 tide and lo...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： W.Wan Z.Ren F.Ding j.xiong L.Liu B.Ning B.Zhao G.Li M.-L.Zhang Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences

In this study we numerically investigated the couplings between the non-migrating atmospheric tide in the mesosphere and low thermosphere(MET) and the response wave in the upper thermosphere and *** diurnal eastward wavenumber-3(DE3) tidal mode was considered as the lower boundary perturbation in the simulation based on the Global Coupled Ionosphere-Thermosphere-Electrodynamics Model,developed by the Institute of Geology and Geophysics,Chinese Academy of Sciences(GCITEM-IGGCAS).We then obtained the longitudinal wavenumber-4(WN4) structure in the upper thermosphere and ionosphere by running GCITEM-IGGCAS with some devised control conditions. The simulated results are treated as the contribution of the two mechanisms:the upward tidal wave propagation and the electro-dynamical *** examples,we analyzed in detail the WN4 structure of both neutral mass density and electron number density in the upper thermosphere and ionospheric F2-region(～400 km altitude) at an afternoon time(15:00).The model simulation shows that both the upward wave propagation and the electro-dynamical coupling can produce the thermo-spheric and ionospheric WN4 *** thermospheric WN4 waves are directly produced by the wave propagation mechanism;they are also indirectly created by the mechanism of electro-dynamical coupling combined with ion-neutral ***,the ionospheric WN4 waves are directly produced by the electro-dynamical coupling;and they can also be indirectly excited by the mechanisms of upward wave propagation combined with neutral-ion *** is found that the solar activity seriously affects the DE3-WN4 coupling *** the solar activity increases,rapid decrease occurs for both the thermospheric and ionospheric WN4 intensity related to the wave propagation mechanism,while only little change is found for that corresponding to the electro-dynamical coupling. Further quantitative analysis lead to the conclusion that the electro-dynamical

关键词： DE3-WN4 coupling Upward tidal wave propagation Electro-dynamical coupling

Planetary wave-type oscillations in the ionosphere and their relationship to mesospheric/lower thermospheric *** disturbances at Wuhan(30.61N,114.51E)

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Planetary wave-type oscillations in the ionosphere and their...

中国科学院地质与地球物理研究所2006学术年会

作者： j.xiong~(a,_),W.Wan~a,B.Ning~a,L.Liu~a,Y.Gao~b a Institute of Geology and Geophysics,The Chinese Academy of Sciences,P.O.Box 9825,Beijing 100029,PR China b Institute of Geophysics,China Seismological Bureau,Beijing,PR China

Using wind,ionospheric and geomagnetic intensity data observed simultaneously at Wuhan(30.61N,114.51E) in 2002 and 2003,planetary wave type oscillations(PWTO) in the ionosphere and their relationship with oscillations in the mesosphere/lower thermosphere(MLT) and geomagnetic intensity have been *** cases of 2- and 5-day oscillations in the ionosphere are analyzed to distinguish MLT drivers and geomagnetic *** geomagnetic oscillations are the most important drivers for the PWTO with dominant periods of 5-,10-, *** the planetary waves in MLT winds are the main drivers for the quasi-2-day oscillations in the *** correlation coefficient of the occurrence rates of the 2-day oscillation in winds and in ionospheric f0F2 is 0.82 for the data from February to *** oscillations in the geomagnetic intensity can drive 30-50%of 5-,10- and 13.5-day PWTO events in the *** we evaluate all of the possible events driven by geomagnetic oscillations, more than 70%of the events have a relationship with geomagnetic oscillations with 5- and 10-day *** 39.7 h PWTO in ionospheric plasma frequencies observed from day 161 to 166 in 2002,are generated by an upward propagating wave with period 43.8 *** events of 6-day oscillations in the ionosphere observed during May to july in 2003,have different *** first one is probably generated by 5.4-day upward propagating waves in MLT winds,but enhanced during a moderate geomagnetic *** second one is generated by the geomagnetic oscillations during a strong geomagnetic storm,r 2005 Elsevier *** rights reserved.

关键词： Planetary wave Ionosphere Mesosphere and lower thermosphere

Two-way shape memory effect in a Ti-Zr-Nb-Ta high-temperature shape memory alloy

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Rare Metals 2024年第3期43卷 1257-1262页

作者： Cheng-Yang xiong Tuo Li jun Wang Yan Li School of Materials Science and Engineering Beihang UniversityBeijing100191China

The two-way shape memory effect in a Ti-18.5Zr-10Nb-3.5Ta high-temperature shape memory alloy was investigated.X-ray diffraction measurem ent shows that the alloy is composed of orthorhombicα"-martensite.ωphase is not found in Ti-18.5Zr-10Nb-3.5Ta alloy due to the suppressing effect of Ta ***α"-martensite laths are found in the transmission electron microscope observation;after the bending deformation,there appear a lot of *** alloy exhibits a shape memory strain of 3.8%aud a high reverse martensite transformation start temperature of 464 *** maximum two-way shape memory strain of 1.2%is obtained in the alloy with the prebending training strain of 10%.The mechanism can be ascribed to the effect of internal stress field caused by dislocations.

关键词： Ti-Zr Shape memory alloys Two-way shape memory effect

Correlation between the ionospheric WN4 signature and the upper atmospheric DE3 tide

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Correlation between the ionospheric WN4 signature and the up...

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： W.Wan,j.xiong,Z.Ren,L.Liu,M.-L.Zhang,F.Ding,B.Ning,B.Zhao, and X.Yue 1 Beijing National Observatory of Space Environment,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing,100029,China.

[1]The present work studies the correlation relationship between the longitudinal ionospheric structure of wave number 4(WN4) and the upper atmospheric tide of nonmigrating tidal mode DE3(diurnal eastward wave number 3).Global ionospheric maps produced by the jet Propulsion Laboratory were used to deduce the latitudinal integration of total electron content in the low-latitude ionosphere,and TIDI/TIMED observations were used to retrieve the atmospheric zonal and meridional *** applying Fourier filtering and fitting techniques,the WN4 wave and DE3 tidal components are derived from the ionospheric and upper atmospheric observations,*** found that the observed WN4 wave and DE3 zonal wind components experience very similar annual and interannual variations,but the DE3 meridional wind component behaves in a quite different *** WN4 and DE3 zonal winds are very intense during northern summer and autumn;they also appear in the later spring,but tend to vanish in winter. Their amplitudes increase as the solar activity decreases,and both are stronger in the quasi-biennial oscillation(QBO) eastward wind phase than in the westward *** the same time,the DE3 meridional wind likes to occur only in winter and seems not change with solar activity and QBO *** further studied the correlation between the WN4 wave and the two wind components of the DE3 *** found that the cross-correlation coefficient between the WN4 wave and the DE3 zonal wind is much larger,while that between the WN4 wave and the DE3 meridional wind is relatively *** different correlations are attributed to the different latitudinal symmetry of different DE3 wind *** DE3 zonal wind is likely in latitudinally symmetric tidal mode;hence,it can efficiently affect the F region ion *** contrast,the meridional wind is mainly in antisymmetric mode and thus seldom affects the ionospheric *** present results support the suggestion that the longitudinal WN4 s

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Wavenumber-4 patterns of the total electron content over the low latitude ionosphere

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Wavenumber-4 patterns of the total electron content over the...

中国科学院地质与地球物理研究所2008学术年会

作者： W.Wan,L.Liu,X.Pi,M.-L.Zhang,B.Ning,j.xiong,and F.Ding 1 Institute of Geology and Geophysics,Chinese Academy of Sciences, Beijing,China. 2 jet Propulsion Laboratory,California Institute of Technology, Pasadena,California,USA.

[1]The global ionospheric maps(GIMs) produced by jPL are used to investigate the longitudinal structure of the low latitude *** a proxy of the ionization parameter at low latitudes,the latitudinally integrated total electron content(ITEC) is first extracted from low latitude GIMs and then Fourier filtered to obtain the wavenumber-4 *** then study in detail the diurnal,seasonal and solar cycle variations of the wave *** is found that the wavenumber-4 patterns are intense and well developed in boreal summer and early boreal autumn,but quite weak in boreal *** seasonal variation is consistent with that of the zonal wind of the non-migrating tide mode *** also found that the wavenumber-4 patterns shift eastward with a shifting speed that is smaller in daytime than at *** is attributed to the contribution of both the eastward propagation of DE3 in E-region and the zonal E×B ion drifts in *** results support the suggestion that the longitudinal wavenumber-4 structure of the low latitude ionosphere should be originated from the non-migrating tide mode DE3.

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Analysis method and experimental study of ice accumulation detection signal based on Lamb waves

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Chinese journal of Aeronautics 2024年第8期37卷 388-403页

作者： Yanxin ZHANG Hongjian ZHANG Xian YI Binrui WU Xianlei GUAN jianjun xiong Key Laboratory of Icing and Anti/De-icing China Aerodynamics Research and Development CenterMianyang 621000China State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China

A quantitative identification method for in-flight icing has the capability to significantly enhance the safety of aircraft *** guided waves have the unique advantage of detecting icing in a relatively large area,but quantitative identification of ice layers is a *** this paper,a quantitative identification method of ice accumulation based on ultrasonic guided waves is ***,a simulation model for the wave dynamics of piezoelectric coupling in three dimensions is established to analyze the propagation characteristics of Lamb waves in a structure consisting of an aluminum plate and an ice *** wavelet transform method is utilized to extract the Time of Flight(ToF)or Time of Delay(ToD)of S_(0)/B_(1) mode waves,which serves as a characteristic parameter to precisely determine and assess the level of ice ***,an experimental system is developed to evaluate the feasibility of Lamb waves-based icing real-time detection in the presence of spray ***,a combination of the Hampel median filter and the moving average filter is developed to analyze ToF/ToD *** simulation results reveal a positive correlation between geometric dimensions(length,width,thickness)of the ice layer and ToF/ToD of B1 mode waves,indicating their potential as indicators for quantifying ice *** results of real-time icing detection indicate that ToF/ToD will reach greater peak values with the growth of the arbitrary-shaped ice layer until saturation to effectively predict the simulation *** study lays a foundation for the practical application of quantitative icing detection via ultrasonic guided waves.

关键词： Ice Ice accumulation Ultrasonic sensor Ultrasonic guided wave Lamb wave Wavelet transform