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The Character of Photo-electrochemistry of Palladium Implanted TiO_2 nano-crystalline Electrode

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Chinese Chemical Letters 2001年第1期12卷 73-74页

作者： Cun Zhong ZHANG Jing YANG Zhong Da WU Sheng Min CAI En Qin GAO Department of Chemistry Beijing Normal UniversityBeijing 100875 Department of Chemistry Peking UniversityBeijing 100871

A new electrode was prepared by using Pd implanted into nano-crystalline TiO2 and the character of photo-electrochemistry of implanted electrodes was investigated. The energy band structure of nano-crystalline TiO2 has not changed after implantation with Pd. The photo-current (i(ph)) of palladium implanted TiO2 nano-crystalline electrode is larger than that of pure TiO2 nanocrystalline electrode.

关键词： ion implantation photo-electrochemistry titanium dioxide palladium nano-crystalline

Study of nano-crystalline Silicon Films

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Science China Mathematics 1993年第2期36卷 248-256页

作者：何宇亮刘湘娜王志超程光煦王路春于是东 Department of Physics Nanjing University Nanjing 210008 PRC Laboratory of Solid State Microstructures Nanjing University Nanjing 210008 PRC

By using strong hydrogen dilution of silane in PECVD system and controlling the deposition parameters strictly, we have prepared a-Si:H and nc-Si:H as well as μc-Si:H films respectively. The structural characters of nc-Si: H films detected by means of HREM, Raman and X-ray diffraction spectra are identified as coinciding with the known definition of nanometer solids. The unique electrical and optical properties of nc-Si:H films are considered as the consequence of its novel structures.

关键词： nano-crystalline silicon deposition mierostructure.

Preparation of nano-crystalline Tungsten Carbide Thin Film by Magnetron Sputtering and Their Electrocatalytic Property for PNP Reduction

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Chinese Chemical Letters 2005年第11期16卷 1539-1542页

作者： Hua Jun ZHENG Jian Guo HUANG Chun An MA Department of Applied Chemistry Research Center of Nano Science ＆ Technology Zhejiang University of Technology Hangzhou 310032

nano-crystalline tungsten carbide thin films were deposited on Ni substrates by magnetron sputtering using WC as target material. The crystal structure and morphology of the thin films were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM） Electrochemical investigations showed that the electrode of the thin film exhibited higher electrocatalytic activity in the reaction of p-nitrophenol （PNP） reduction. FT-IR analysis indicated that p-aminophenol （PAP） was synthesized after two step reduction of PNP on nano-crystalline tungsten carbide thin film electrode.

关键词： Tungsten carbide nano-crystalline electrocatalyst p-nitrophenol.

PREPARATION OF nano-crystalline Fe-Cu THIN FILMS AND THEIR MAGNETIC PROPERTIES

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 109-112页

作者： X.F. Bi S.K. Gong H.B. Xu K.I Department of Materials Science and Engineering Beijing University of Aeronautics and AstronauticsBeijing 100083 China Research Institute of Electrical Communication Tohoku University Japan

Fe-Cu thin films of 0.2 mum in thickness with different Cu contents wereprepared by using r.f. magnetron sputtering onto glass substrate. The effect of sputteringparameters, including Ar gas pressure and input rf power, on the structure and magnetic propertieswas investigated. It was found that when the power is lower than 70W, the structure of the filmsremained single bcc-Fe phase with Cu solubility of up to 50at. percent. TEM observations for thebcc-Fe phase showed that the grain size was in the nanometer range of less than 20nm. The coercivityof Fe- Cu films was largely affected by not only Ar gas pressure but also rf power, and reachedabout 2.5Oe in the pressure of 0.67-6.67Pa and in the power of less than 100W. In addition,saturation magnetization, with Cu content less than 60at. percent, was about proportional to thecontent of bcc-Fe. When Cu content was at 60at. percent, however, saturation magnetization was muchsmaller than its calculation value.

关键词： Fe-Cu thin film magnetic property sputtering condition nano-crystalline

Reinforcement of Lignin-Based Phenol-Formaldehyde Adhesive with nano-crystalline Cellulose (NCC): Curing Behavior and Bonding Property of Plywood

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Materials Sciences and Applications 2015年第6期6卷 567-575页

作者： Zhenbo Liu Yaolin Zhang Xiangming Wang Denis Rodrigue Key Laboratory of Bio-Based Material Science and Technology (Ministry of Education) & Northeast Forestry University Harbin China FPInnovations-Wood Products Quebec Canada Department of Chemical Engineering Laval University Quebec Canada

The curing behavior of lignin-based phenol-formaldehyde (LPF) resin with different contents of nano-crystalline cellulose (NCC) was studied by differential scanning calorimetry (DSC) at different heating rates (5, 10 and 20°C/min) and the bonding property was evaluated by the wet shear strength and wood failure of two-ply plywood panels after soaking in water (48 hours at room temperature and followed by 1-hour boiling). The test results indicated that the NCC content had little influence on the peak temperature, activation energy and the total heat of reaction of LPF resin at 5 and 10°C/min. But at 20°C/min, LPF0.00% (LPF resin without NCC) showed the highest total heat of reaction, while LPF0.25% (LPF resin containing 0.25% NCC content) and LPF0.50% (LPF resin containing 0.50% NCC content) gave the lowest value. The wet shear strength was affected by the NCC content to a certain extent. With regard to the results of one-way analysis of variance, the bonding quality could be improved by NCC and the optimum NCC content ranged from 0.25% to 0.50%. The wood failure was also affected by the NCC content, but the trend with respect to NCC content was not clear.

关键词： Lignin-Based Phenol-Formaldehyde Resin (LPF) nano-crystalline Cellulose (NCC) Curing Behavior Bonding Properties Plywood

Hexagonal nano-crystalline BCN Films Grown on Si (100) Substrate Studied by X-Ray Absorption Spectroscopy

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Materials Sciences and Applications 2013年第5期4卷 11-19页

作者： Md. Abdul Mannan Yuji Baba Norie Hirao Tetsuya Kida Masamitsu Nagano Hideyuki Noguchi Department of Chemistry and Applied Chemistry Faculty of Science and Engineering Saga University Saga Japan Department of Chemistry and Applied Chemistry Faculty of Science and Engineering Saga University Saga Japan Synchrotron Radiation Research Unit Quantum Beam Science Directorate Japan Atomic Energy Agency Ibaraki Japan Synchrotron Radiation Research Unit Quantum Beam Science Directorate Japan Atomic Energy Agency Ibaraki Japan

Hexagonal nano-crystalline boron carbonitride (h-BCN) films grown on Si (100) substrate have been precisely investigated. The films were synthesized by radio frequency plasma enhanced chemical vapor deposition using tris-dimethylamino borane as a single-source molecular precursor. The deposition was performed by setting RF power at 400 - 800 W. The reaction pressure was at 2.6 Pa and the substrate temperature was recorded at 700°C - 800°C. Formation of the nano-crystalline h-BCN compound has been confirmed by X-ray diffraction analysis. The diffraction peaks at 26.3° together with a small unknown peak at 29.2° were elucidated due to the formation of an h-BCN structure. The films composed of B, C, and N atoms with different B-N, B-C, C-N chemical bonds in forming the sp2-BCN atomic configuration studied by X-ray photoelectron spectroscopy. Orientation and local structures of the h-BCN hybrid were studied by near-edge X-ray absorption fine structure (NEXAFS) measurements. The dominant presence of p* and s* resonance peaks of the sp2-hybrid orbitals in the B K-edge NEXAFS spectra revealed the formation of the sp2-BCN configuration around B atoms like-BN3 in h-BN. The orientation was suggested on the basis of the polarization dependence of B K-edge and N K-edge of the NEXAFS spectra.

关键词： nano-crystalline h-BCN Films Synchrotron Radiation XPS NEXAFS Orientation

Synthesis and characteristics of W-Ni-Fe nano-composite powders prepared by mechanical alloying

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中国有色金属学会会刊：英文版 2000年第2期10卷 172-175页

作者：曲选辉范景莲黄伯云 Cent S Univ Technol State Key Lab Powder Met Changsha 410083 Peoples R China

The mixture of 90W 7Ni 3Fe(mass fraction, %) powders was milled in a planetary ball mill. Its structure changed during milling, the surface characteristics and thermal stability of the milled powders were studied with X ray diffraction(XRD), Brunaure Emmett Teller (BET) nitrogen adsorption technique and differential thermal analysis(DTA). The results show that high energy ball milling leads to the formation of composite powders with amorphous binder phase and supersaturated W(Ni, Fe) nano crystalline grains in which great lattice distortion exists. The crystallization temperature of the amorphous binder phase during heating decreases with milling time. The specific surface area and the pore size of the powder mixtures decreases with milling time due to agglomeration and welding between particles.

关键词： tungsten-based heavy alloy mechanical alloying nano-crystalline powder

Microstructures and mechanical properties of nanocrystalline NiTi intermetallics formed by mechanosynthesis

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 80-87页

作者： S.Arunkumar P.Kumaravel C.Velmurugan V.Senthilkumar Vinayaka Mission's Kimpananda Variyar Engineering College Salem 636308TamilnaduIndia Institute of Road and Transport Technology Erode 638316TamilnaduIndia National Institute of Technology Trichy 620015TamilnaduIndia

The formulation of nanocrystallinc NiTi shape memory alloys has potential effects in mechanical stimulation and medical im- plantology. The present work elucidates the effect of milling time on the product＇s structural characteristics, chemical composition, and mi- crohardness for NiTi synthesized by mechanical alloying for different milling durations. Increasing the milling duration led to the formation of a nanocrystalline NiTi intermetallic at a higher level. The formation of nanocrystalline materials was directed through cold fusion, fractur- ing, and the development of a steady state, which were influenced by the accumulation of strain energy. In the morphological study, uninter- rupted cold diffusion and fracturing were visualized using transmission electron microscopy. Particle size analysis revealed that the mean particle size was reduced to -93 μm after 20 h of milling. The mechanical strength was enhanced by the formation of a nanocrystalline in- termetallic phase at longer milling time, which was confirmed by the results of Vickers hardness analyses.

关键词： nickel-titanium shape memory alloy lattice strain nano-crystalline mechanical alloying microstructural characterization

Fractal characteristics of surface morphology for hydrogenated silicon films

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Chinese Science Bulletin 1996年第19期41卷 1659-1665页

作者：何宇亮万明芳袁凯华戎霭伦魏希文 Amorphous Physics Research Laboratory Beijing University of Aeronautics and Astronautics Beijing 100083 China Department of Physics Dalian University of TchnologyDalian 116024China

Hydrogenated nanocrystalline silicon films (nc-Si:H) are a developing novel man-made functional semiconductor material in recent years. Their strange microstructure and physical properties of nc-Si:H films are attracting our attention. We have used the conventional structure analysis procedures, such as X-ray diffraction pattern, Raman scattering spectrum, high resolution transmission electron microscopy (HREM), and the scanning tunnelling microscope (STM), to analyze their microstructure. Since Mandelbrot proposed the fractal theory in 1982, it has become a quantitatively characterizing means to distinguish the microstructure morphology of materials. Recently, the fractal

关键词： micro-crystalline silicon films nano-crystalline silicon films fractal morphology.