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Acta Metallurgica Sinica(English letters) 2002年第1期15卷 39-44页

作者： P. Wu F.P. Wang l.q. pan Y. Tian H. qiu Dept. of Phys. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Cu films with thickness of 630-1300nm were deposited on glass substrates without heating by DC magnetron sputtering in pure Ar gas. Ar pressure was controlled to 0.5, 1.0 and 1.5Pa respectively. The target voltage was fixed at 500V but the target current increased from 200 to 1150mA with Ar pressure increasing. X-ray diffraction, scanning electron microscopy and atomic force microscopy were used to observe the structural characterization of the films. The resistivity of the films was measured using four-point probe technique. At all the Ar pressures, the Cu films have mixture crystalline orientations of [111], [200] and [220] in the direction of the film growth. The film deposited at lower pressure shows more [111] orientation while that deposited at higher pressure has more [220] orientation. The amount of larger grains in the film prepared at 0.5Pa Ar pressure is slightly less than that prepared at 1.0Pa and 1.5Pa Ar pressures. The resistivities of the films prepared at three different Ar pressures represent few differences, about 3-4 times of that of bulk material. Besides the deposition rate increases with Ar pressure because of the increase in target current. The contribution of the bombardment of energetic reflected Argon atoms to these phenomena is discussed.

关键词： Cu film DC magnetron sputtering deposition Ar pressure structure reststivity

THE EFFECTS OF SPUTTERING POWER ON STRUCTURE AND ElECTRICAl PROPERTIES OF Cu FIlMS

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Acta Metallurgica Sinica(English letters) 2002年第2期15卷 215-220页

作者： F.P. Wang. P. Wu, l.q. pan, Y. Tian and H. qiu Department of Physics, School of Applied Sciences, University of Science and Technology Beijing, Beijing 100083, China Beijing Keda-Tianyu Microelectronic Material Technology Development Co. ltd., Beijing 100 Beijing Keda-Tianyu Microelectronic Material Technology Development Co. ltd. Beijing 100083China

Cu films with thickness of about 500nm were deposited on glass substrateswithout heating by DC magnetron sputtering in pure Ar gas of 1.0Pa. The sputtering powers weremaintained at 390V X 0.27A, 430V X 0.70A and 450V X l.04A, and the corresponding deposition rates ofCu film reached 35nm/min, l04nm/min and 167nm/min. X-ray diffraction, scanning electron microscopyand atomic force microscopy were used to observe the structural characteristics of the films. Theresistance of the films was measured using four-point probe technique. The amount of larger grainsincreases and the resistivity of the films decreases evidently with an increase in sputtering *** is considered that the increase in deposition rate with sputtering power mainly weakens theinfluence of residual gas atoms on the growing film, and increases substrate and gas temperatures,resulting in the increase in grain size and the decrease in resistivity of the Cu film.

关键词： Cu film DC magnetron sputtering sputtering power structure resistivity

SPIN-DEPENDENT TUNNElING MAGNETORESISTANCE IN Fe-O/AlO_x/Fe-O FIlMS

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Acta Metallurgica Sinica(English letters) 2002年第2期15卷 233-237页

作者： l.q. pan, H. qiu. F.P. Wang, P. Wu.Y’. Tian and S. luo Department of Physics. University of Science and Technology Beijing, Beijing 100083, China Beijing Keda-Tianyu Microelectronic Materials Technology Development Co. ltd., Rm 105 Keji Building. 30 Xueyu Beijing Keda-Tianyu Microelectronic Materials Technology Development Co. ltd. Rm105 Keji Building30 Xueyuan Rd. Haidian DistrictBeijing 100083China

Fe-O/AlO_x/Fe-O tunnel junctions were prepared by reactive magnetronsputtering under mixed working gas Ar+2 percent O_2. The insulating AlO_x layer of 1-2nm thicknesswas sputtered directly from A1_2O_3 target. Electrode layers were made of 80at. percent iron and20at. percent oxygen. Bottom Fe-O electrode deposited on glass substrate annealed at 473K at thepressure of 3 X 10^(-4) Pa for an hour shows disparate crystalline grain structure, lower electricalresistance and coercivity compared to the as-deposited top electrode. Only crystalline structrureof alpha-Fe is observed in both electrodes. large tunnel magnetoresistance in large Fe-O/AlO_x/Fe-Ojunctions of 1cm^2 is observed at room temperature and the I-V characteristic curve of the junctionshows that the barrier of the junction is of high quality.

关键词： spin- dependent tunneling magnetoresistance magnetic thin film

Deciphering the role of mtH2O2 in hepatic ischemia-reperfusion injury mechanisms with low-background super-resolution fluorogenic probe

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Science China Chemistry 2025年第1期68卷 297-307页

作者： Bin Fang limin Wang Haoqin li Jiaxin Zhang Yang Ding pan pan li Bo Peng Hua Bai lin li Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials &Engineering Northwestern Polytechnical University Institute of Flexible Electronics (IFE Future Technologies) Xiamen University

Hepatic ischemia-reperfusion injury（HIRI） is characterized by mitochondrial dysfunction and oxidative stress. Monitoring mitochondrial hydrogen peroxide（mtH2O2） levels in real-time through super-resolution imaging is crucial for elucidating its distribution in live cells and its mechanism of action during HIRI. However, low-background fluorogenic probes have been overlooked in the context of super-resolution imaging. In this study, we developed a low-background fluorogenic probe（MitoWG） with the potential for super-resolution morphology-correlated mitochondrial identification to track the fluctuates of mtH2O2in HIRI. Activation of the desirable fluorescence properties of the probe by mtH2O2was confirmed using structural illumination microscopy（SIM）, enabling high-quality mitochondrial imaging with exceptional specificity and *** in mtH2O2levels were successfully observed in both cellular and rat models of HIRI. Furthermore, we associated the decline in mitochondrial redox homeostasis with accelerated mtH2O2production during HIRI, which triggered mitophagy deficiency and led to cell death. In conclusion, Mito-WG possesses excellent photophysical and low-background properties for SIM imaging, making it a promising tool for mtH2O2tracking in HIRI research and clinical diagnosis.

关键词： hepatic ischemia-reperfusion injury low-background mtH2O2-activatable super-resolution imaging fluorogenic probe

MODElING OF STATIC RECRYSTAllIZATION KINETICS OF Nb-BEARING STEElS

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Acta Metallurgica Sinica(English letters) 2006年第4期19卷 271-278页

作者： l.q. Ma Z.Y. liu S.H. Jiao X.q. Yuan D. Wu The State Key laboratory of Rolling and Automation Northeastern UniversityShenyang 110004 China Institute of Research and Development Baosteel Co. Ltd Shanghai 201900 China

By using isothermal double hit compression tests and applying the 2% offset method, a new model was developed to predict the microstructural evolution of Nb-bearing steels at temperatures above and below the start temperature of strain-induced precipitation （Tp）. The Tp was developed as a function of true strain, initial austenite grain size and the Nb content. The activation energy of static recrystallization （qrex） was expressed as a function of the content of different alloy elements. It was found that Nb played the most important role in increasing the value of qrex, The microstructural observations and measurements confirmed the validity of the model developed in the present investigation.

关键词： Nb-bearing steel static recrystallization Tp (start temperature of strain-induced precipitation) activation energy

Facile immobilization of heparin on bioabsorbable iron via mussel adhesive protein(MAPs)

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Progress in Natural Science:Materials International 2014年第5期24卷 458-465页

作者： Xuchen Xu Ming li qian liu Zhaojun Jia Yuying Shi Yan Cheng Yufeng Zheng l.q. Ruan Center for Biomedical Materials and Tissue Engineering Academy for Advanced Interdisciplinary StudiesPeking University Department of Materials Science and Engineering College of Engineering Peking University Department of Mechanical Systems Engineering Graduate School of Science and TechnologyKumamoto University

Motivated by adhesive proteins in mussels, strategies using dopamine to modified surface have become particularly attractive. In the present work, we developed a novel and convenient method to modify the biodegradable Fe plates with heparin. Iron was first treated by a facile one-step p H-induced polymerization of dopamine, and then a high density heparin was successfully grafted onto the surface via coupling with polydopamine(PDA) active layer. Heparin immobilization contributed much longer blood clotting coagulation time than the pure Fe sample, and hence reduced the risk of thrombosis. Cell viability tests suggested that the heparin modified Fe plates were more favorable to the proliferation of ECV304 cells. In summary, the heparin modified Fe plates with good anti-thrombus properties and inhibiting the proliferation of VSMC cells provide great prospects for biodegradable iron.

关键词： Iron Heparin Dopamine Surface modification Biodegradable stent Hemocompatibility

HIGH ACCURACY FOR MIXES FINITE ElEMENT METHODS IN RAVIART-THOMAS ElEMENT

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Journal of Computational Mathematics 1996年第2期14卷 175-182页

作者： lin, q pan, JH CHINESE ACAD SCI INST SYST SCIBEIJINGPEOPLES R CHINA UNIV PETR DEPT BASIC SCIBEIJINGPEOPLES R CHINA

This paper deals with Raviart-Thomas element (q(2,1) x q(1,2) - q(1) element). Apart from its global superconvergence property of fourth order, we prove that a postprocessed extrapolation can globally increased the ac... 详细信息

关键词： Math Wang HIGH ACCURACY FOR MIXES FINITE ElEMENT METHODS IN RAVIART-THOMAS ElEMENT

Dynamic Coordination of Uncalibrated Hand/Eye Robotic System Based on Neural Network

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Journal of Systems Engineering and Electronics 2001年第3期12卷 45-50页

作者： Su, J. pan, q. Xi, Y. Institute of Automation Shanghai Jiaotong University Shanghai 200030 China

A nonlinear visual mapping model is presented to replace the image Jacobian relation for uncalibrated hand/eye coordination. A new visual tracking controller based on artificial neural network is designed. Simulation results show that this method can drive the static tracking error to zero quickly and keep good robustness and adaptability at the same time. In addition, the algorithm is very easy to be implemented with low computational complexity.

关键词： Adaptive algorithms Computational complexity Computer simulation Coordinate measuring machines Error detection Mathematical models Neural networks Robotic arms Robustness (control systems) Stereo vision

Terahertz band simulations using two different radiative transfer models

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Science China Earth Sciences 2018年第10期61卷 1482-1490页

作者： linjun pan Daren lü laboratory for Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences

A high-resolution dual-band terahertz(THz) radiometer was designed to measure vertical distributions of chemical elements in the middle atmosphere of the Tibetan Plateau. A forward simulation, which always should be conducted firstly for the development of a matching retrieval algorithm, has not been done before. We use two radiative transfer models, ARTS and AM, to simulate the water vapor, ozone and carbon monoxide spectra on the plateau based on the spectral design of the THz radiometer. The emission line characteristics of the three gases in this spectral band are identified. Reasons for the differences in the spectral simulations between the two models are analyzed for individual gases. The impact of several different spectral parameter settings on the simulations are evaluated through a series of sensitivity experiments. This study suggests that the ARTS is more suitable for the development of the THz radiometer retrieval algorithm. An optimal parameter setting of the ARTS for the three elements are given.

关键词： Terahertz radiation Radiometer Radiative transfer model Spectral simulation Plateau

Stochastic averaging of quasi integrable and resonant Hamiltonian systems excited by fractional Gaussian noise with Hurst index 1/2

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Acta Mechanica Solida Sinica 2017年第1期30卷 11-19页

作者： q.F.lü M.l.Deng W.q.Zhu Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemsKey Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceZhejiang University

A stochastic averaging method of quasi integrable and resonant Hamiltonian systems under excitation of fractional Gaussian noise （fGn） with the Hurst index 1/2 〈 H 〈 1 is proposed. First, the definition and the basic property of fGn and related fractional Brownian motion （iBm） are briefly introduced. Then, the averaged fractional stochastic differential equations （SDEs） for the first integrals and combinations of angle variables of the associated Hamiltonian systems are derived. The stationary probability density and statistics of the original systems are then obtained approximately by simulating the averaged SDEs numerically. An example is worked out to illustrate the proposed stochastic averaging method. It is shown that the results obtained by using the proposed stochastic averaging method and those from digital simulation of original system agree well.

关键词： quasi integrable and resonant Hamiltonian system Fractional Brownian motion Fractional Gaussian noise Stochastic averaging method Internal resonant