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Journal of Magnesium and Alloys 2021年第6期9卷 2155-2168页

作者： Xiyu Yao Jincheng Tang Yinghao Zhou Andrej Atrens Matthew S.Dargusch Bjoern Wiese Thomas Ebel Ming Yan School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China The University of Queensland School of Mechanical and Mining EngineeringCentre for Advanced Materials Processing and Manufacturing(AMPAM)QLD 4072 Australia Institute of Materials Research Helmholtz-Zentrum GeesthachtGeesthacht 21502Germany

Magnesium alloys such as Mg–Ca and Mg–Zn–Ca are good orthopaedic materials;however their tendency to corrode is *** we utilize selective laser melting(SLM)to modify the surface of these Mg alloys to simultaneously improve the corrosion behaviour and *** corrosion rate decreased from 2.1±0.2 mm/y to 1.0±0.1 mm/y for the laser-processed Mg–0.6Ca,and from 1.6±0.1 mm/y to 0.7±0.2 mm/y for laser-processed Mg–0.5Zn–*** microhardness increased from 46±1 HV to 56±1 HV for Mg–0.6Ca,and from 47±3 HV to 55±3 HV for Mg–0.5Zn–*** addition,good biocompatibility remained in the laser processed Mg *** improved properties are attributed to laser-induced grain refinement,confined impurity elements,residual stress,and modified surface *** results demonstrated the potential of SLM as a surface engineering approach for developing advanced biomedical Mg alloys.

关键词： Mg alloys Selective laser melting surface modification Corrosion behaviour Microhardness

surface modification OF POLYPROPYLENE MICROPOROUS MEMBRANES BY THE ADSORPTION OF NON-IONIC SURFACTANTS

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Chinese Journal of Polymer Science 2006年第4期24卷 421-429页

作者：徐志康 Institute of Polymer Science Zhejiang University and Key Laboratory of Macromolecule Synthesis and Functionalization (Zhejiang University) Ministry of Education Hangzhou 310027 China

surface modification by physical adsorption of a series of non-ionic surfactants including Tween 20, Tween 40, Tween 60, Tween 80 and Tween 85, was accomplished on polypropylene microporous hollow fiber and flat membranes. The adsorption curve of the membrane surface was analyzed by weight measurements and the typical results showed a twoplatform character similarly. Differences in the degree and curve shape of adsorption resulting from such factors as concentration, temperature, as well as water cleaning time were observed for Tween 85 among other Tweens. Attenuated total reflection - Fourier transform infrared spectroscopy analysis and field emission scanning electron microscopy observation showed that the adsorption of Tween on polypropylene microporous membrane （PPMM） is effective and occurs mainly in the pores of PPMMs at low adsorption amount, and on the membrane surface also at high adsorption value.

关键词： Polypropylene microporous membranes surface modification Adsorption Surfactants Tween.

surface modification of titanium plate enhanced fibronectin-mediated adhesion and proliferation of MG-63 cells

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Transactions of Nonferrous Metals Society of China 2014年第4期24卷 1065-1071页

作者：周征戴瑶刘斌斌夏磊磊刘洪波 Pankaj VADGAMA 刘海蓉湖南大学生物学院长沙410082 湖南大学材料科学与工程学院长沙410082 IRC in Biomedical Materials Queen Mary University

An understanding of osteoblast adhesion and proliferation on biomaterials is crucial to optimizing the surfaces of artificial implants used in clinical practice. Polished, anodic oxidation （AO） and micro-arc oxidation （MAO） treated titanium （Ti） plates were used as model surfaces to study the adhesion of MG-63 cells. Cells were monitored for 0.5 and 4 h; faster adhesion and spreading of MG-63 ceils were observed on the AO and MAO modified samples. Stimulated secretion of fibronectin （FN） influenced the adhesion rates. In addition, AO and MAO modified surfaces promoted cell proliferation through apparent up-regulation of FN and integrin a5 transcription via outside-in signaling. This strongly suggests that FN secretion by osteoblasts plays an essential role in enhanced cell adhesion, spreading and proliferation on these modified Ti surfaces.

关键词： titanium surface modification Outside-in signaling fibronectin integrin

surface modification of Cu-25Cr alloy induced by high current pulsed electron beam

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Transactions of Nonferrous Metals Society of China 2015年第6期25卷 1935-1943页

作者：周志明柴林江肖志佩涂坚王亚平黄伟九重庆理工大学材料科学与工程学院重庆400054 西安交通大学理学院西安710049

A Cu-25Cr alloy prepared by vacuum induction melting method was treated by the high current pulsed electron beam （HCPEB） with pulse numbers ranging from 1 to 100. surface morphologies and microstructures of the alloy before and after the treatment were investigated by scanning electron microscopy and X-ray diffraction. The results show that significant surface modification can be induced by HCPEB with the pulse number reaching 10. Craters with typical morphologies on the Cu-25Cr alloy surface are formed due to the dynamic thermal field induced by the HCPEB. Micro-cracks, as a unique feature, are well revealed in the irradiated Cu-25Cr specimens and attributed to quasi-static thermal stresses accumulated along the specimen surface. The amount of cracks is found to increase with the pulse number and a preference of these cracks to Cr phases rather than Cu phases is also noted. Another characteristic produced by the HCPEB is the fine Cr spheroids, which are determined to be due to occurrence of liquid phase separation in the Cu-25Cr alloy. In addition, an examination on surface roughness of all specimens reveals that more pulses will produce a roughened surface, as a result of compromising the above features.

关键词： Cu-Cr alloy surface modification high current pulsed electron beam microstructure

surface modification OF POLYPROPYLENE MICROPOROUS MEMBRANE BY TETHERING POLYPEPTIDES

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Chinese Journal of Polymer Science 2006年第5期24卷 529-538页

作者：徐志康 Mathias Ulbricht Institute of Polymer Science Department of Polymer Science & Engineering Zhejiang University Hangzhou 310027 China Institut für Technische Chemie Universit t Duisburg-Essen45117 EssenGermany

Two kinds of polypeptides were tethered onto the surface of polypropylene microporous membrane （PPMM） through a ring opening polymerization of L-glutamate N-carboxyanhydride initiated by amino groups which were introduced by ammonia plasma and y-aminopropyl triethanoxysilane treatments. X-ray photoelectron spectroscopy （XPS）, attenuated total reflectance Fourier transform infrared spectroscopy （FT-IR/ATR）, scanning electron microscopy （SEM）, together with water contact angle measurements were used to characterize the modified membranes. XPS analyses and FT-IR/ATR spectra demonstrated that polypeptides are actually grafted onto the membrane surface. The wettability of the membrane surface increases at first and then decreases with the increase in grafting degrees of polypeptide. Platelet adhesion and murine macrophage attachment experiments reveal an enhanced hemocompatibility for the polypeptide modified PPMMs. All these results give evidence that polypeptide grafting can simultaneously improve the hemocompatibility as well as reserve the hydrophobicity for the membrane, which will provide a potential approach to improve the performance of polypropylene hollow fiber microporous membrane used in artificial oxygenator.

关键词： Polypropylene microporous membrane Graft polymerization Polypeptide surface modification Biocompatibility.

surface modification by Nitrogen Plasma Immersion Ion Implantation on Austenitic AISI 304 Stainless Steel

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Journal of Iron and Steel Research International 2016年第4期23卷 380-384页

作者： Miguel CASTRO-COLIN William DURRER Jorge A. LOPEZ Enrique RAMIREZ-HOMS Max Plank Institute for Intelligente Systems Stuttgart 70569Baden-wurttembergGermany Physics Department University of TexasEl Paso TX79968-0515TexasUSA

surfaces of AISI 304 austenitic stainless steel plates nitrided by plasma immersion ion implantation （PⅢ） technology were studied by means of Auger electron spectroscopy （AES） and X-ray photoelectron spectroscopy （XPS） to determine the effect of the nitriding process on the surface and subjacent layers. Elemental compositions obtained by AES and XPS at varying depths indicate that the saturation of N is relatively constant as a function of depth, indicating the reliability of PⅢ technology for substirface saturation. It is concluded that the concentrations of both Cr and O increase with depth, the subjacent oxide is driven by the Ar^＋ sputtering process used to access the lower layers, and then N is bound to Cr.

关键词： PⅢ technology AISI 304 XPS AES surface modification

surface modification of Poly Vinyl Chloride (PVC) Using Low Pressure Argon and Oxygen Plasma

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Plasma Science and Technology 2010年第2期12卷 204-207页

作者： Mahmood GHORANNEVISS Sheila SHAHIDI Jakub WIENER Plasma Physics Research Center Science and Research Branch Islamic Azad University Department of Textile Chemistry Faculty of Textile Technical University of Liberec

In this study, commercial poly vinyl chloride （PVC） films were treated by oxygen and argon plasmas in a cylindrical glass tube which was surrounded by a DC variable magnetic field, with different sample positions in the plasma reactor and also different exposure durations. Effects of the plasma treatment on the hydrophilic properties of the films were studied by mea- suring the water drop contact angle on the surface of the samples. The surface topography of the untreated and plasma treated films was analyzed and compared by atomic force microscopy （AFM）. The optical characteristic changes in treated samples were investigated using reflective spectrophotometry. Also, the chemical changes which appeared on the surface of the samples were investigated using Fourier transform infrared spectroscopy （FTIR）. The results show that the plasma treated PVC becomes more hydrophilic with an enhanced wettability. A sharp de- crease in the water contact angle may also be a consequence of the surface texturization. The aging effect on wettability of the samples was also investigated. The results show that the effect of oxygen plasma on the surface properties of the samples is more pronounced compared with that of argon plasma.

关键词： plasma surface modification poly vinyl chloride

surface modification of Biodegradable Poly(D,L-lactic acid) by Nitrogen and Nitrogen/Hydrogen Plasma for Improving surface Hydrophilicity

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Plasma Science and Technology 2011年第2期13卷 230-234页

作者：赵国巍高俊萍高强陈亚芍 Key Laboratory of Applied surface and Colloid Chemistry (Shaanxi Normal University) Ministry of Education School of Chemistry and Materials Science Key Laboratory of Modern Preparation of TCM Ministry of Education Jiang Xi University of Traditional Chinese Medicine School of Pharmacy Fourth Military Medical University

Enhancement of the surface hydrophilicity of biodegradable poly （D,L-lactic acid）（PLA） films is studied. The PLA films were treated by nitrogen plasma （PLA-N2） and nitro- gen/hydrogen plasma （PLA-N2/H2）, respectively. The surface properties and microstructure of PLA-N2 and PLA-N2/H2 were studied by static contact angle measurement, surface free energy calculation, X-ray photoelectron spectroscopy （XPS） and atomic force microscopy （AFM）. It is confirmed that the surface hydrophilicity of PLA-N2 and PLA-N2/H2 was higher than that of pristine PLA, and the surface hydrophilicity of PLA-N2 films was better than that of PLA-N2/H2.

关键词： plasma surface modification PLA films hydrophilicity

surface modification of (Tb_(0.3)Dy_(0.7))Fe_(1.95) alloy by ion nitriding process

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Journal of Rare Earths 2009年第2期27卷 240-243页

作者：李扩社李红卫严辉于敦波王丰瀛张世荣张国成 National Engineering Research Center for Rare Earth Materials General Research Institute for Non-Ferrous Metalsand Grirem Advanced Materials Co.Ltd.Beijing 100088China College of Materials Science and Engineering Beijing University of TechnologyBeijing 100022China

Effect of ion nitriding modification on surface hardness, corrosion resistance and magnetostriction of （Tb0.3Dy0.7）Fe1.95 alloy was investigated. Results demonstrated that a 100-200 nm thick nitrided layer was formed on the sample surface by ion nitriding treatment, which improved obviously surface hardness, wear, and corrosion resistance properties of （Tb0.3Dy0.7）Fe1.95 alloys. The surface hardness was increased from HV587 to HV622 after ion nitriding at 650 K for 6 h. Furthermore, ion nitriding treatment had almost no influence on mag- netostrictive performance as the nitrided layer was quite thin and the treatment temperature was not too high. The results might provide us a new approach for surface modification of （Tb0.3Dy0.7）Fe1.95 alloy.

关键词： magnetostfiction ion nitriding surface modification (Tb0.3Dy0.7)Fe1.95 rare earths

surface modification of Fluororubber Using Atmospheric Pressure Dielectric Barrier Discharge(DBD)

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Plasma Science and Technology 2007年第3期9卷 296-300页

作者：童薇卢灿辉蔡勇昆黄奕刚 State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu 610065China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China

Fluoride rubber F2311 film, an alternating copolymer of CF2-CFC1 （CTFE） and CH2-CF2 （VF2） components, was treated by atmospheric pressure dielectric barrier discharge （DBD） in air. The surface structure, topography and surface chemistry of the treated F2311 films were characterized by contact angle measurement, atomic force microscopy （AFM）, and X-ray photoelectron spectroscopy （XPS）, respectively. The experimental results showed that a short time air plasma treatment led to morphological, wettability and chemical changes in the F2311 films. The surface hydrophilicity increased greatly after the plasma treatment, the static water contact angle decreased from 98.6° to 32°, and oxygen containing groups （C=O, O-C=O, etc. ） were introduced. Atomic force microscopy revealed that plasma produced by DBD etched F2311 films obviously. The roughness of the samples increased remarkably with the formation of peaks and valleys on the treated surfaces. The increased surface wettability may be correlated with both the introduction of hydrophilic groups due to air plasma oxidation of the surface and the change in surface morphology etched by DBD.

关键词： fluororubber dielectric barrier discharge (DBD) surface modification contact angle atomic force microscopy (AFM) X-ray photoelectron spectroscopy (XPS)