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surface properties of nitrogen-ion-implanted TiNi shape memory alloy

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Journal of University of Science and Technology Beijing 2006年第2期13卷 154-157页

作者： Chongyan Leng Teruo Asaoka Rong Zhou School of Materials and Metallurgical Engineering Kunming University of Science and Technology Kunming 650093 China Department of Intelligent and Mechanical Engineering Tokyo Denki University Hatoyama Hiki-Gun Saitama 350-0394 Japan School of Mechanical Engineering Kunming University of Science and Technology Kunming 650093 China

X-ray diffraction （XRD）, auger electron spectroscopy （AES）, and X-ray photoelectron spectroscopy （XPS） were used to characterize the surface properties of the N^ ＋-ion-implanted TiNi alloy. There is a high nitrogen content region at the outermost surface of the N^＋-ion-implanted TiNi alloy. The detected nitrogen exists mainly in the form of TiN. Small amounts of Ti305 and TiO2 also exist on the surface of the N^＋-ion-implanted TiNi sample. The modified layer of the N^＋-ion-implanted sample can work as an obstacle layer of the nickel＇s dissolution, which obstructs Ni dissolving from the TiNi surface effectively.

关键词： shape memory alloys TiNi surface properties

Synthesis, UV-curing Behavior and surface properties of New Fluorine-containing Aromatic Oxetane Monomers

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Chinese Journal of Polymer Science 2018年第4期36卷 521-527页

作者： Shu-Qing Fang Yu-Lian Pang Ying-Quan Zou College of Chemistry Beijing Normal University

In this paper, we combined high-end cationic UV-curable material with fluorinated chain obtaining a series of new fluorine-containing aromatic oxetane monomers via a mild nucleophilic substitution reaction. The structures and properties of monomers were characterized using ~1 H-NMR, ^（19） F-NMR, dynamic viscosity tests and differential scanning calorimetry（DSC）. It was determined that all of the fluorinated monomers obtained had much lower viscosity and higher thermostability after the introduction of hexafluorobenzene. Then, UV-curable coatings were prepared using four fluorine-containing aromatic oxetane monomers（FOX1-4）; the UV-curing kinetics, with three kinds of initiators, and properties of the cured films were evaluated using real-time Fourier transform infrared（FTIR） spectroscopy, water and diiodomethane contact angle tests, surface energy calculations and scanning electron microscopy（SEM）. The FTIR spectroscopy results showed that the coatings possessed excellent conversion rate（〉 99% with liquid initiator PAG-201 in 150 s）, and as the fluorine content increased, the monomers exhibited decreased mobility with the increasing viscosity and worse solubility with fluorinated monomers, resulting in a lower conversion rate. Moreover, the coatings possessed favorable hydrophobic and oleophobic properties and low surface energies owing to the fluoride chains floating to the membrane-air interface, which was also confirmed by discrete concave structures in SEM images. These new kinds of monomers can replace traditional fluorinated cationic monomers applied to the fingerprint resistant, fouling resistant, scratch resistant and anti-aging coatings, adhesives or printing ink materials.

关键词： Fluorine-containing monomers Oxetane UV-curing kinetics surface properties

Effects of Zr/Ti molar ratio in SO_4^(2-)/ZrO_(2-)TiO_2 calcined at different temperatures on its surface properties and glucose reactivity in near-critical methanol

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Journal of Natural Gas Chemistry 2012年第2期21卷 138-147页

作者： Lincai Peng Junping Zhuang Lu Lin State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou 510640GuangdongChina School of Energy Research Xiamen UniversityXiamen 361005FujianChina

Effects of Zr/Ti molar ratio in SO42-/ZrO2-TiO2 solid acid catalyst calcined at different temperatures on its surface properties and catalytic activity were thoroughly investigated in this paper. The physicochemical characteristics of prepared samples were determined by N2 adsorptiondesorption, XRD, NH3-TPD and XPS techniques, respectively. It was found that the crystallization temperature of the samples increased after the combination of ZrO2 and TiO2; and phase transformations from the anatase to the rutile of TiO2 species and the tetragonal to the monoclinic of ZrO2 species were effectively suppressed at higher temperature. The sample with a Zr/Ti molar ratio of 3/1 calcined at 450℃ showed the highest surface area and the most acid sites among all the tested samples. The acid site densities of samples were relatively closed to each other if they were calcined at the same temperature, however, decreased with the calcination temperature. The result indicates that the sulfur content in samples is a crucial factor to control the acid site density. Calcining the sample at 650℃ and higher temperatures resulted in a significant desorption of sulfate ion on the samples. The synthesized samples were evaluated as a potential catalyst for glucose conversion under the near-critical methanol conditions （200℃/4 MPa）. The results suggested that the relatively weaker acid sites of the catalyst were more favorable for the accumulation of methyl glucosides, while the moderate acid sites were responsible for the formation of methyl levulinate. The catalytic activity for methyl levulinate production almost increases linearly with the catalyst acid site density. The catalyst deactivation is due to the loss of sulfate ion and the two catalysts with Zr/Ti molar ratios of 3/1 and 1/3 could effectively alleviate the deactivation caused by sulfate solution in the reaction medium and can be reused after calcination with the reuse rate of over 90% in terms of the methyl levulinate selectivi

关键词： SO42-/ZrO2-TiO2 surface properties catalysis glucose reactivity methyl levulinate

The Impact of surface properties on Downward surface Shortwave Radiation over the Tibetan Plateau

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Advances in Atmospheric Sciences 2015年第6期32卷 759-771页

作者： WANG Leidi L Daren HE Qing Key Laboratory of Middle Atmosphere and Global Environmental Observation Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

The complexity of inhomogeneous surface-atmosphere radiation transfer is one of the foremost problems in the field of atmospheric physics and atmospheric radiation. To date, the influence of surface properties on shortwave radiation has not been well studied. The daily downward surface shortwave radiation of the latest FLASHFlux/CERES （Fast Longwave And Shortwave Fluxes_Time Interpolated and Spatially Averaged/Clouds and the Earth＇s Radiant Energy System） satellite data was evaluated against in situ data. The comparison indicated that the differences between the two data sets are unstable and large over rugged terrain compared with relatively flat terrain, and the mean absolute error of the satellite products reaches 31.4 W m-2 （12.3%） over rugged terrain. Based on the SSF （single satellite footprint）/CERES product, the influence of surface properties on the distribution of downward surface shortwave radiation （DSSR） was analyzed. The influence of surface properties on DSSR over the Tibetan Plateau is about twice as large as that in two other regions located at the same latitude （eastern China-western Pacific and subtropical North Pacific）. A simulation was carried out with the help of the I3RC （International Intercomparision of Three-Dimensional Radiation Code） Monte Carlo 3D radiative transfer community model. The results showed that DSSR increases as surface albedo increases. Moreover, the impact of surface albedo on DSSR is larger if the spatial distribution of clouds is more non-uniform. It is hoped that these results will contribute to the development of 3D radiative transfer models and the improvement of satellite inversion algorithms.

关键词： shortwave radiation surface properties Tibetan Plateau satellite remote sensing

Preparation and surface properties of Silicon-Containing Waterborne Polyurethane Functionalized with Fluorine-Containing Acrylate and Micro-Nano Silica

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Journal of Wuhan University of Technology(Materials Science) 2018年第1期33卷 233-241页

作者：蔡棋 HUANG Jiemin 翁睿 LIU Shichen School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 China

In order to prepare hydrophobic waterborne polyurethane coatings with better performances, the silicon-containing waterborne polyurethane（SiWPU） with functional chain extender hydroxyethyl acrylate（HEA） was prepared first, and then a series of silicon＆fluorine-containing polyurethane/acrylate（FSiPUA） emulsions were obtained with flourine containing acrylic monomer by seed emulsion polymerization, introducing micro-nano SiO2 into FSiPUA emulsion to make the final hybrid emulsion. The properties of Si WPU, FSiPUA and SiO2/FSiPUA were investigated by fourier transform infrared spectra（FTIR）, transmission electron microscope（TEM）, Scanning Electron Microscope（SEM） and some other analytical methods. The results revealed that FSiPUA emulsion particles possessed composite core-shell structure and FSiPUA films with suitable ratio performed better than Si WPU films in hardness, water resistance and solvent resistance. The SiO2/FSiPUA films with micro-nano dual roughness structure showed a water contact angle of 136° with good resistance to acid and alkali.

关键词： waterborne polyurethane acrylic SiO2 surface properties

COMPARISON OF surface properties OF Ti-6Al-4V COATED WITH TITANIUM NITRIDE, TiN+TiC+Ti(C,N)/DLC, TiN/DLC AND TiC/DLC FILMS BY PLASMA-BASED ION IMPLANTATION

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Acta Metallurgica Sinica(English Letters) 2000年第4期13卷 967-973页

作者： Ji, H.B. Xia, L.F. Ma, X.X. Sun, Y. Sun, M.R. Harbin Inst of Technology Harbin China

The surface properties of Ti-6Al-4V alloy coated with titanium nitride, TiN+TiC+Ti(C,N)/DLC (diamond like carbon), TiN/DLC and TiC/DLC films by plasma-based ion implantation (PBII) with nitrogen, PBII with nitrogen then acetylene, PBII with nitrogen then glow discharge deposition with acetylene plus hydrogen and PBII with acetylene then glow discharge deposition with acetylene plus hydrogen respectively were studied. The corresponding films are found getting dimmer, showing light gold or gold, smoky color (uneven), light red in black (uneven), and graphite black separately. The corresponding film resistivities are given. Antioxidation ability of the titanium nitride film is poor, while the existence of carbon (or carbide) improves the antioxidation ability of the films. Having undergone excellent intermediate transitional region of nitrogen and carbon implantation, the top DLC layer of the TiN+TiC+Ti(C,N)/DLC multilayer are formed after the carbon implantation has the best adhesion with the substrate among all the multilayers. Although microhardness of the samples increases in the order of coatings of titanium nitride, TiN/DLC, TiN+TiC+Ti(C,N)/DLC and TiC/DLC, the TiN/DLC and TiC/DLC multilayers have greater brittleness as compared with other films.

关键词： Titanium alloys Titanium nitride Plasmas Ion implantation Microhardness surface properties

Induced surface Austenitic-Martensitic Transition by Mechanical Deformation in Mn *** of surface properties

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Journal of Iron and Steel Research(International) 2011年第S1期18卷 223-227页

作者： Boutarek-Zaourar Nama Mansour Samir Amara Sif Eddine USTHB FGMGPBP 32 EL ALIA BAB EZZOUARALGER USTHB FCBP 32 EL ALIA BAB EZZOUARALGER

For a lot of applications in the mechanical industry,both attractive and mechanical properties of materials and wear resistance are *** such a combination is achieved only by performing surface *** aim of this investigation is the consolidation of 12% Mn steel surface by treatment of *** show by optical and scanning electron microscopy,X ray diffraction,X ray spectrometry analysis and also by the realization of micro hardness,the effect of this kind of treatment on the mechanical and structural stability of the surface *** of many obtained results,we distinguish the clear surface consolidation induced by a modification of surface zone crystalline *** mechanical deformation causes the transformation from an austenitic structure to the martensitic structure.

关键词： phase transition Mn steel mechanical deformation surface properties impact treatment

Sol-gel synthesis, surface and magnetic properties of nanocrystalline SmAlO_3

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Journal of Rare Earths 2010年第4期28卷 602-605页

作者： Dimitar Petrov Bogdan Angelov Vasil Lovchinov Department of Inorganic and Physical Chemistry University of Food Technologies 26 Maritsa Blvd. 4002 Plovdiv Bulgaria Institute of Solid State Physics Bul garian Academy of Sciences 72Tzarigradsko Chaussee Blvd. 1784 Sofia Bulgaria

Nanocrystals of single-phase samarium monoaluminate (SmAlO3) were synthesized and studied for the first time. Malic acid was employed as a new complexing agent in the sol-gel process. The material was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDS), specific surface area and density. The lowest size of the nanoparticles was about 50–60 nm and some of them formed agglomerates. The binding energies of core-level electrons of Sm (3d, 4d, 4f, ...

关键词： SmAlO3 nanocrystals surface properties magnetic susceptibility rare earths

Effect of surface properties of Colloidal Particles and Substrates on Vertical Deposition Assembly Method

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Effect of Surface Properties of Colloidal Particles and Subs...