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Synthesis and Characterization of PEG-like Structures on Nitinol Surface under ECR-cold-plasma

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Journal of wuhan University of technology(Materials Science) 2005年第1期20卷 33-36页

作者：杨隽 Institute of Plasma physics Chinese Academy of Sciences Anhui 230031 China school of Materials Science and Engineering Wuhan Institute of Chemical Tech nologyWuhan 430073China

The synthesis and characterization of PEG-like macromolecular structures on Nit inol surface from tri (ethylene glycol) dimethyl-ether under ECR-cold-plasma conditions were discussed. It was demonstrated that based on high-resolution ES CA, ATR-FTIR and contact angle investigations, the deposited PEG-like layers a re composed mainly of -CH 2.CH 2.O- linkages. These structures have a relati vely low contact angle. Compared to the unmodified surfaces, the plasma-treated Nitinol surfaces are more hydrophilic. Plasma enhanced coatings of PEG-like la yers can prevent Ni ion from releasing, thereby improving the biocompatibility o f Nitinol.

关键词： cold-plasma Nitinol modification PEG-like s tructures

Energy dissipation and angular momentum transfer within a magnetically torqued accretion disc

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 106-109页

作者： GAN ZhaoMing,WANG DingXiong,LEI WeiHua & LI Yang school of physics,Huazhong University of Science and {2.,wuhan 4.0074.{4. school of physics Huazhong University of Science and Technology Wuhan China

We discuss transportation and redistribution of energy and angular momentum in the magnetic connection(MC) process and Blandford-Payne(BP) *** results in readjusting the interior viscous torque,and its effects are operative not only in but also beyond the MC *** BP process is invoked to transfer the "excessive" angular momentum from an accretion *** addition,we derive a criterion for the interior viscous torque to resolve the puzzle of the overall equilibrium of angular momentum in disc *** turns out that the efficiency of BP at extracting angular momentum and the intensity of the outflow are required to be greater than some critical values.

关键词： accretion:accretion discs black hole physics magnetic field angular momentum transfer

Friction-reducing and antiwear behavior of metal halide-stabilized linear phosphazene derivatives as lubricants for a steel-on-steel contact

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Science china(Technological Sciences) 2005年第3期48卷 282-291页

作者： ZHU Jiamei 1,2., LIU Weimin 2.& LIANG Yongmin 2.1. school of Chemical Engineering and {4., {2. University of Mining and {4., Xuzhou 2.1008, {2. 2. State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical physics, Chinese Academy of Sciences, Lanzhou 730000, {2. school of Chemical Engineering and technology China University of Mining and Technology Xuzhou China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou China

A series of novel metal halide-stabilized linear phosphazene derivatives were synthesized. The friction-reducing and antiwear abilities of the resulting products as the lubricants for a steel-on-steel contact were comparatively investigated on an Optimol SRV oscillating friction and wear tester. The morphology of the worn steel surface was observed on a scanning electron microscope, while the chemical states of some typical elements on the worn steel surface were examined by means of X-ray photoelectron spectroscopy. It was found that both the side branch structures and central metals influenced the friction-reducing and antiwear behaviors of the synthetic derivatives as the lubricants, which was related to the different adsorption activities of the organic compounds composed of different organic ingredients and metallic ions on a nascent metal surface. All the synthetic lubricants except for the iron (III) derivative showed increased antiwear abilities with increasing metallic ionic radius. A protective layer originated from the tribochemical reaction together with the adsorbed boundary lubricating layer containing organic fluorine compounds, nitrogen oxide, and Fe 3 (PO 4.) 2.plays an important role in improving the friction and wear behavior of the steel-on-steel system.

关键词： metal halide-stabilized linear phosphazene derivatives,lubricant,steel,tribological properties.

ASYMPTOTIC BEHAVIOR FOR RANDOM WALK IN RANDOM ENVIRONMENT WITH HOLDING TIMES

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Acta Mathematica Scientia 2010年第5期30卷 1696-1708页

作者：毛明志李志民 school of Mathematics and physics China University of Geosciences Department of Applied Mathematics and physics Anhui Institute of Science and Technology

In this article, we mainly discuss the asymptotic behavior for multi-dimensional continuous-time random walk in random environment with holding times. By constructing a renewal structure and using the point ＂environment viewed from the particle＂, under General Kalikow＇s Condition, we show the law of large numbers （LLN） and central limit theorem （CLT） for the escape speed of random walk.

关键词： random walk random environment central limit theorem law of large numbers renewal structure

Manufacture of the Ultrafine Grain WC/Co Cemented Carbides by Combined Sintering Processing

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 208-213页

作者： Binghai Liu Yue Zhang Shixi Ouyang Qikai Li(Institute of Technical physics and Chemistry, East china University of Science and {2. , Shanghai 2.02.7, china)(Material Science and Engineering school. University of Science and {2. Beijing, Beijing 100083, china)(State Key Laboratory for Synthesis and Processing of Advanced Materials. wuhan University of Science and {2., wuhan 4.0070, china,) Institute of Technical physics and Chemistry East China University of Science and Technology Shanghai 200237 China State Key Laboratory for Synthesis and Processing of Advanced Materials Wuhan University of Science and Technology Wuhan 430070 China Material Science and Engineering school University of Science and Technology Beijing Beijing 100083 China

A new kind of sintering process, combined sintering process. i.e. vacuum sintering plus hot isolate pressure sintering (HIP), was introduced for producing ultrafine WC-10% Co (mass fraction. so as the follows) cemented carbides. The effects of some processing parameters on the microstructure and mechanical properties of the obtained cemented carbides were studied. The results show that the rapid shrinkage and the pronounced densification of tile cemented carbides took place during the vacuum sintering stage, which is intinaately correlated with the local liquid sintering occurred during this earl} sintering stage for the high surface activity of ultrafine WC-Co powder. The way of high pressure imposing. isothermal treatment cycle during *** sintering and HIP sintering stage directly influence the densitication of compacts and the mechanical properties of the produced WC-10%Co cemented carbides.

关键词： ultrafine WC-Co cemented carbides vacuum sintering HIP sintering

Role of Bound States in Channel-Interference of Harmonic Generation

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wuhan University Journal of Natural Sciences 2011年第2期16卷 161-166页

作者： CAO Hui CAI Jun QIAO Haoxue school of physics and {2. Wuhan University Wuhan430072 Hubei China

We calculated the power spectra of harmonic generation for the one-electron system in 7 potential models with different quantities of bound states. It indicates that the increase of weakly bound states has little influence on the enhancement of harmonic intensity in the high-order region. Further research on the so-called channel-interference of harmonic generation is obtained, which shows that the channel-interference of harmonic generation exists for all potential models. Therefore, channel-interference maybe a ubiquitous phenomenon for one-electron system driven by bichromatic field, and the increase of bound states can augment the effect of channel-interference. Our calculations can provide some insight on the mechanism of channel-interference and harmonic generation.

关键词： harmonic generation channel-interference bound states potential models

Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

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Science china Chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2. WANG Jin3, WU Yishi1, YUAN Gu3, AI Xicheng1, WANG Li4.& ZHANG Jianping1 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, china 2. school of Life Science and {2., Beijing Institute of {2., Beijing 100081, china 3. College of Chemistry and Molecular Engineering, Peking University, Beijing 100080, china 4. Center for Condensed Matter physics, Institute of physics, Chinese Academy of Sciences, Beijing 100080, china Correspondence should be addressed to Ai Xicheng and Zhang Jianping State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing China school of Life Science and technology Beijing Institute of Technology Beijing China College of Chemistry and Molecular Engineering Peking University Beijing China Center for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 32.ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

Synthesis of Polyaniline-Fe_3O_4.Nanocomposites and Their Conductivity and Magnetic Properties

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Journal of wuhan University of technology(Materials Science) 2010年第5期25卷 760-764页

作者：冷春江 Key Laboratory of Artificial Microand Nano-structures of Ministry of Education and school of physics and {2. Wuhan University

By using inorganic Fe3O4.nanoparticles of different content as nucleation sites, PAn-Fe3O4.nanorods were successfully synthesized through a simple, conventional, and inexpensive one-step in-situ polymerization method. The TEM images revealed the size and morphology of the resultant nanocomposite. The EDS pattern confirmed the existence of Fe3O4.in the composite. The FT-IR spectral analysis confirmed the formation of PAn encapsulated Fe3O4.nanocomposite. With the content of Fe3O4.increasing, the conductivity of the nanocomposites gradually decreases, meanwhile, the saturation magnetization increases and reveals a super paramagnetic behavior. With controllable electrical, magnetic, and electromagnetic properties, the well-prepared nanocomposites may have the potential applications in chemical sensors, catalysis, microwave absorbing, and electro-magneto-rheological fluids, etc.

关键词： polyaniline Fe3O4 nanocomposites conductivity super paramagnetism

C^MC^N D-computable state

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Science china(physics,Mechanics & Astronomy) 2008年第9期51卷 1300-1307页

作者： LIU DongDong1,2.& DI YaoMin1 1 school of physics & Electronic Engineering,Xuzhou Normal University,Xuzhou 2.1116,{2. 2.school of Mathematics & physics Science,Xuzhou Institute of technology,Xuzhou 2.1008,{2. school of physics & Electronic Engineering Xuzhou Normal University Xuzhou China school of Mathematics & physics Science Xuzhou Institute of Technology Xuzhou China

The notions of D-computable state and D-concurrence are generalized to the CMCN system. A class of D-computable state on CMCN is given and the calculating method of the lower bound of D-concurrence is provided. Th... 详细信息

关键词： quantum entanglement entanglement of formation concurrence D-computable state