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Journal of Materials Science & Technology 2022年第23期118卷 35-43页

作者： Xi.Rao l.Du J.J.zhao X.D.Tan y.X.Fang l.Q.Xu y.P.Zhang School of Materials and Energy Southwest UniversityChongqing 400715China Chongqing Key laboratory of Soft-Matter Material Chemistry and Function Manufacturing Southwest UniversityChongqing 400715China

The hybrid TiO_(2)/AgNPs/g-C_(3) N_(4) nanocomposite coatings were constructed on TC4 alloy by a hydrothermal and calcining ***_(2)/AgNPs/g-C_(3) N_(4) nanocomposite coatings demonstrated excellent biocompatibility and osteogenesis compared to those of titanium *** existence of trace AgNPs on the surface and interface of the heterojunction could further enhance the transfer and separation of photogenerated electron/hole pairs,which greatly improved the antibacterial performance under full spectrum *** at the valence band of TiO_(2) and g-C_(3) N_(4) reacted with adsorbed H_(2) O to generate·OH,killing bacteria through photocatalytic redox reaction under light irradiation,while released AgNPs exhibited bacteriostatic efficacy with or without *** study provides a pathway of coating modification for further improving the antibacterial properties of heterojunction coatings and maintaining the biocompatibility of matrix materials.

关键词： TiO_(2)/AgNPs/g-C_(3)N_(4)nanocomposite g-C_(3)N_(4) Photocatalysis Photocatalytic inactivation of bacteria Disinfection mechanism

Influences of Reaction Parameters and Ce Contents on Structure and Properties of Nano-scale Ce-HA Powders

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Journal of Materials Science & Technology 2014年第8期30卷 776-781页

作者： l.J.Sun D.G.Guo W.A.zhao l.y.Wang K.W.Xu State Key laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong University Chao Family Comprehensive Cancer Center Department of Pharmaceutical SciencesUniversity of California Irvine Sue and Bill Gross Stem Cell Research Center University of California Irvine The Key laboratory of Bioactive Materials Ministry of EducationCollege of Life SciencesNankai University Xi'an University of Arts and Science

Ce-incorporated apatite（Ce-HA） nano-scale particles with different Ce percentage contents（atomic ratio of Ce to Ce ＋ Ca is 5%,10%and 20%,respectively） were synthesized via a simple wet chemical method in this *** crystal structure,chemical groups,thermal stability,crystal morphologies and crystal sizes of the Ce-HA nano-particles were characterized by X-ray diffraction（XRD）,Fourier transform infrared spectroscopy（FTIR）,and transmission electron microscopy（TEM）.The influences of reaction temperature,reaction time,pH value,and the atomic ratio of Ce to Ce ＋ Ca on the structure and performance of Ce-HA particles were *** results show that the lattice constants,particle sizes,crystallinity and thermal stability of Ce-HA vary with the doped Ce *** the increase of Ce content,the lattice constants of the Ce-HA nano-particles remarkably increase but the particle size,crystallinity and thermal stability gradually *** reaction temperature as well as the reaction time has no significant effect on the properties of the final products,while the pH value has a direct relationship with their final chemical *** obtained Ce-HA nanosize particles possess potential application in preparing artificial bone implants,bone tissue engineering scaffold and other bioactive coatings.

关键词： Cerium Apatite Nano-scale powder Wet chemical approach Biomedical materials

Compressive properties of a novel slurry-infiltrated fiber concrete reinforced with arc-shaped steel fibers

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第6期24卷 543-556页

作者： Hedong lI yabiao lI yunfeng PAN P.l.NG Christopher K.y.lEUNG Xin zhao School of Civil Engineering and Architecture Zhejiang Sci-Tech UniversityHangzhou 310018China Department of Civil Engineering The University of Hong KongHong Kong 999077China Faculty of Civil Engineering Vilnius Gediminas Technical UniversityVilnius LT-10223Lithuania Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong Kong 999077China School of Civil Engineering and Architecture Zhejiang University of Science and TechnologyHangzhou 310023China

Slurry-infiltrated fiber concrete(SIFCON)is a sort of strain hardening cement-based composite material,typically made with 5%–20%steel *** study focused on a novel type of SIFCON in which hooked-end steel fibers were replaced by arc-shaped steel *** quasi-static compressive properties of the SIFCON were first *** results suggested that using arc-shaped steel fibers in lieu of hooked-end steel fibers increased the quasi-static compressive strength by 47.1%and the strain at peak stress by 56.3%.We attribute these improvements to new crack-resisting mechanisms,namely“fiber crosslock”,“dual bridging”,and“confinement loops”,when the arc-shaped steel fibers are introduced into *** high impact resistance is a special property of SIFCON that is of practical significance,the dynamic compressive properties of arc-shaped steel fiber SIFCON were studied by using an 80-mm-diameter split Hopkinson pressure bar(SHPB).The results showed that the dynamic compressive strength,dynamic increase factor(DIF),and dynamic toughness of SIFCON all increased with the strain *** SIFCON incorporating arc-shaped steel fibers proved to have significant advantages in structural applications requiring high impact resistance.

关键词： Slurry-infiltrated fiber concrete(SIFCON) Arc-shaped steel fiber Quasi-static compressive properties Spilt Hopkinson pressure bar(SHPB) Dynamic compressive properties

PHASE TRANSFORMATION BEHAVIOR AND MICROSTRUCTURE OBSERVATION OF Nb-Ru HIGH TEMPERATURE SHAPE MEMORy AllOy

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Acta Metallurgica Sinica(English letters) 2003年第5期16卷 401-406页

作者： X.Gao y.F.Zheng W.Cai l.C.zhao SchoolofMaterialsScienceandEngineering HarbinInstituteofTechnologyHarbin150001China 不详

The phase transformation behavior and micro structure of Nb-Ru alloys have been studied by DSC, X-ray diffraction, optical microscopy, transmission electron microscopy (TEM) and high-resolution electron microscopy (HREM). Two-step phase transformation of CsCl (β) →face-centered tetragonal (β)→ monoclinic (β') occurs during cooling from high temperature to room temperature. The lattice parameters of marten-sites of Nb-Ru alloys were found to increase with the increase of Nb content. The martensite variants exhibit triangular self-accommodating morphology, with alternating regular bands inside. The twinning relationship between the sub structural bands was found to be (101) type I mode, and this kind of twinning interface was straight, well-defined and coherent.

关键词： Nb-Ru alloy shape memory alloy (SMA) phase transformation micro structure.

Surface engineering and the application of laser-based processes to stents-A review of the latest development

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Bioactive Materials 2022年第4期7卷 159-184页

作者： J.Dong M.Pacella y.liu l.zhao Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLeicestershireLE113TUUK Centre for Biological Engineering Loughborough UniversityLoughboroughLeicestershireLE113TUUK

late in-stent thrombus and restenosis still represent two major challenges in stents’*** treatment of stent is attracting attention due to the increasing importance of stenting intervention for coronary artery *** surface engineering techniques have been utilised to improve the biological response in vivo on a wide range of biomedical *** a tailorable,precise,and ultra-fast process,laser surface engineering offers the potential to treat stent materials and fabricate various 3D textures,including grooves,pillars,nanowires,porous and freeform structures,while also modifying surface chemistry through nitridation,oxidation and ***-based processes can reduce the biodegradable materials’degradation rate,offering many advantages to improve stents’performance,such as increased endothelialisation rate,prohibition of SMC proliferation,reduced platelet adhesion and controlled corrosion and ***,adequate research has been conducted on laser surface texturing and surface chemistry *** texturing on commercial stents has been also investigated and a promotion of performance of laser-textured stents has been *** this critical review,the influence of surface texture and surface chemistry on stents performance is firstly reviewed to understand the surface characteristics of stents required to facilitate cellular *** is followed by the explicit illustration of laser surface engineering of stents and/or related *** induced periodic surface structure(lIPSS)on stent materials is then explored,and finally the application of laser surface modification techniques on latest generation of stent devices is highlighted to provide future trends and research direction on laser surface engineering of stents.

关键词： Surface engineering laser surface engineering Stent Cell response laser textured stents

Oxidation behavior and microstructural evolution of FeCoNiTiCu five-element high-entropy alloy nanoparticles

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Journal of Materials Science & Technology 2024年第10期177卷 133-141页

作者： H.Bai R.Su R.Z.zhao C.l.Hu l.Z.Ji y.J.liao y.N.Zhang y.X.li X.F.Zhang Key laboratory for Anisotropy and Texture of Materials(MOE) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China Institute of Advanced Magnetic Materials College of Materials and Environmental EngineeringHangzhou Dianzi UniversityHangzhou310012China

High-entropy alloys(HEAs)have attracted extensive attention ascribed to their unique physical and chemical properties induced by the cocktail ***,their oxidation behaviors,in particular at nanoscale,are still lack because of multi-element complexity,which could also be completely differ-ent from the bulk *** this work,we synthesized FeCoNiTiCu five-element HEA nanopar-ticles(NPs)with uniform elemental distribution by arc-discharging approach,and further investigated their oxidation behaviors at 250 ℃,and 350 ℃.The morphology,structure and element distribution of NPs were analyzed by transmission electron microscopy(TEM),energy dispersive spectroscopy(EDS)and electron energy loss spectroscopy(EElS).The surface oxidation in FeCoNiTiCu NPs during the high-temperature process can induce nanoscale pores at core/shell interfaces by Kirkendall effect,and even the eventual coalescence into a single ***,the oxidation states of NPs with diameters(d)varying from 60 to 350 nm were analyzed in detail,revealing two typical configurations:hollow(dyolk-shell structures(d>150 nm).The experimental results were complemented by first-principles calculations to investigate the diffusion behaviors of five elements,evidencing that the surface oxidation strongly alters the surface segregation preferences:(1)in the initial stage,Cu and Ni appear to prefer segregating on the surface,while Co,Ti and Fe tend to stay in the bulk;(2)in the oxidation process,Cu prefers to stay in the center,while Ti segregates to the surface ascribed to the reduced po-tential *** study gives new insights into oxidation of nanoscale HEA,and also provides a way for fabrication of high-entropy oxides with controllable architectures.

关键词： High-entropy alloy Nanoparticles Oxidation Kirkendall effect Exchange bias effect

Improved data gap-filling schemes for estimation of net ecosystem exchange in typical East-Asian croplands

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Science China Earth Sciences 2016年第8期59卷 1652-1664页

作者： zhao Peng Johannes lüERS Department of Micrometeorology University of Bayreuth Institute of Ecology University of Innsbruck Member of Bayreuth Center of Ecology and Environmental Research (BayCEER) University of Bayreuth

The estimation of carbon exchange between ecosystems and the atmosphere suffers unavoidable data gaps in eddy-covariance technique, especially for short-living and fast-growing croplands. In this study we developed a modified gap-filling scheme introducing a leaf area index factor as the vegetation status information based on the conventional light response function for two East-Asian cropland sites (rice and potatoes). This scheme’s performance is comparable to the conventional time window scheme, but has the advantage when the gaps are large compared to the total length of the time series. To investigate how the time binning approach performs for fast-growing croplands, we tested different widths of the time window, showing that a four-day window for the potato field and an eight-day time window for the rice field perform the best. The insufficiency of the conventional temperature binning approach was explained as well as the influence of vapor pressure deficit. We found that vapor pressure deficit plays a minor role in both the potato and the rice fields under Asian monsoon weather conditions with the exception of the early pre-monsoon growing stage of the potatoes. Consequently, we recommend using the conventional time-window scheme together with our new leaf-light response function to fill data gaps of net ecosystem exchange in fast-growing croplands.

关键词： Eddy-covariance Gap-filling Net ecosystem exchange lAI

Effects of Growth Temperature on Structural and Electrical Properties of li-N-H Codoped ZnO

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Journal of Materials Science & Technology 2013年第2期29卷 154-156页

作者： y.F. lu Z.Z. ye l.P. Zhu y.J. Zeng J.y. Huang B.H. zhao State Key laboratory of Silicon Materials Department of Materials Science and Engineering Zhejiang University

Effects of growth temperature on the structural and electrical properties of li-N-H codoped ZnO thin films grown by DC reactive magnetron sputtering were investigated. Scanning electron microscopy and X-ray diffraction results showed that increasing growth temperature could improve the crystalline quality. But Hall measurement results showed that growth temperature had a nonlinear influence on the electrical property. The variation of electrical properties with the growth temperature was found to be related to the activated concentration of N in ZnO and the evaporation of li during the growth process, derived from the Hall measurement and the second ion mass spectroscopy measurement.

关键词： ZnO Codoped Growth temperature Structural property Electrical property

ON FATIGUE CRACK PATH DEVIATION AT ElEVATED TEMPERATURE IN ElECTRON BEAM REPAIRED WElDMENTS OF TURBINE DISK

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Acta Metallurgica Sinica(English letters) 2004年第4期17卷 584-590页

作者： H.Q.Zhang H.y.zhao y.H.Zhang l.H.li X.A.Zhang Department of Mechanical Engineering Tsinghua University Beijing 100084 ChinaDepartment of Mechanical Engineering Tsinghua University Beijing 100084 ChinaSchool of Mechanical Engineering and Automation Beijing University of Aeronautics and AstronauticsBeijing 100083 ChinaSchool of Mechanical Engineering and Automation Beijing University of Aeronautics and AstronauticsBeijing 100083 ChinaBeijing Institute of Aeronautical Materials Beijing 100095 China

Fatigue crack growth behaviors in electron beam weldments of a nickel-base superalloy are studied. The objective of this paper is to discuss effects of the inhomogeneity of mechanical performance on fatigue crack growth (FCG) rate and crack path deviation (CPD). The base metal served in a turbine disk of aerospace engine was selected to fabricate bead-on-plate weldments by using electron beam welding. Some wedge-type opening loading specimens, notched in three different zone of weld metal, HAZ and base metal, were employed and performed fatigue crack growth tests at 650℃. The results show that the fatigue crack growth of electron beam welded joints is instable due to the influence of mechanical heterogeneities. Owing to the crack deviation at the weld metal and heat-affected-zone (HAZ), the effective growth driving force at the tip of fatigue crack was reduced with the reduction of the effective stress intensity factor (SIF) which finally causes fatigue crack rate decrease. Fatigue crack was strongly affected by size and the symmetrical characteristics of the plastic zone at the crack tip, which means that the integrity of the welded structure containing the fatigue crack mainly depended on the toughness of the low strength zone.

关键词： fatigue crack growth crack path deviation electron beam welding inhomogeneity of mechanical performance

STRUCTURE AND BINDING STATE OF CN_x FIlMS SyNTHESIZED By FACING TARGETS SPUTTERING

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Acta Metallurgica Sinica(English letters) 1999年第5期12卷 752-756页

作者： Tang, D.Q. Wang, y. Jiang, E.y. zhao, C. Sun, F.l. Tianjin Univ Tianjin China

CN x films were made by a facing targets sputtering ( FTS) systemon the  Si(100) substrate under different  N 2 partial pressure.  XRD, XPS, FTIR and Raman Spectroscopy( RS) were measured to investigate the structure and the binding state of the film. The films are amorphous and the  N/C increases with the  N 2 partial pressure increasing and reaches 0 46 when the  N 2 pressure is 100%. The N incorporated  C forms N sp 2C and N sp 3C mainly and there is a small amount of  C≡N.

关键词： Amorphous films Hard disk storage Hardness Nitrides Silicon wafers Sputtering Synthesis (chemical)