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Microstructure and properties of aging Cu–Cr–Zr alloy

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Rare Metals 2014年第2期33卷 134-138页

作者： Kun Wang Ke-Fu Liu jing-bo zhang Institute of Electric Lighting Source Fudan University No.23 Research Institute China Electronics Technology Group Corporation No. 23 Research Institute China Electronics Technology Group Corporation

The crystallography and morphology of precipitate particles in a Cu matrix were studied using an aged Cu–Cr–Zr alloy by transmission electron microscopy（TEM） and high-resolution transmission electron microscopy（HRTEM）. The tensile strength and electrical conductivity of this alloy after various aging processes were tested. The results show that two kinds of crystallographic structure associated with chromium-rich phases, fcc and bcc structure, exist in the peak-aging of the alloy. The orientation relationship between bcc Cr precipitate and the matrix exhibits Nishiyama–Wasserman orientation relationship. Two kinds of Zr-rich phases（Cu4Zr and Cu5Zr）can be identified and the habit plane is parallel to {111}Cu plane during the aging. The increase in strength is ascribed to the precipitation of Cr- and Zr-rich phase.

关键词： Cu–Cr–Zr alloy Aging process Crystallography Morphology Strengthening mechanism

Quantized Nanocrystalline CdTe Thin Films

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Chinese Chemical Letters 2001年第8期12卷 751-752页

作者： jing bo zhang Yuan LIN Yao LIU Xu Rui XIAO Center of Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080

Nanocrystalline CdTe thin films were prepared by asymmetric rectangular pulse electrodeposition in organic solution at 110 degreesC. STM image shows a porous network morphology constructed by interconnected spherical CdTe crystallites with a mean diameter of 4.2 nm. A pronounced size quantization was indicated in the action and absorption spectra. Potentials dependence dual conductive behavior was revealed in the photocurrent-potential (I-V) curves.

关键词： nanocrystalline CdTe thin film asymmetric rectangular pulse electrodeposition size quantization dual conductive behavior

Dye-sensitized solid-state solar cells fabricated by screen-printed TiO_2 thin film with addition of polystyrene balls

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Chinese Chemical Letters 2008年第8期19卷 1004-1007页

作者： jing Han Jin Mao Chen Xiao Wen Zhou Yuan Lin jing bo zhang Jian Guang Jia Department of Chemistry School of Science Beijing University of Chemical Technology Beijing 100029 China Key Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

The screen-printed nanoporous TiO2 thin film was employed to fabricate dye-sensitized solid-state solar cells using CuI as hole-transport materials. The solar cell based on nanoporous TiO2 thin film with large pores formed by the addition of polystyrene balls with diameter of 200 nm to the TiO2 paste exhibits photovoltaic performance enhancement, which is attributed to the good contact of CuI with surface of dye-sensitized thin film due to easy penetration of CuI in the film with large pores.

关键词： Dye-sensitized solar ceils Screen-printed TiO2 film Cuprous iodide Polystyrene balls

Electrodeposition of SnO_2 nanocrystalline thin film using butyl-rhodamine B as a structure-directing agent

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Chinese Chemical Letters 2010年第12期21卷 1505-1508页

作者： jing Yang Shou Li Bai Rui Xian Luo Ai Fan Chen Yuan Lin jing bo zhang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Beijing National Laboratory for Molecular Sciences Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

Porous SnO2 nanocrystalline thin films were successfully electrodeposited from an oxygen-saturated acid aqueous solution of SnCl2 containing different concentrations of butyl-rhodamine B（BRhB） at 70℃.BRhB with substitute of amidocyanogen can be dissolved in the acid deposition solution,where HCl was added to suppress hydrolysis of *** it was used as a structure-directing agent to promote the crystal growth of SnO_*** formed porous morphology and tetragonal rutile crystalline structure of the electrodeposited thin films were controlled by the addition of BRhB with different amounts.

关键词： Nanocrystalline SnO2 thin film Electrodeposition Butyl-rhodamine B Structure-directing agent

Electrochemical impedance analysis of nanoporous TiO_2 electrode at low bias potential

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Chinese Chemical Letters 2010年第8期21卷 959-962页

作者： Sheng Jun Li Yuan Lin Zeng Chen jing bo zhang Xiao Wen Zhou College of Physics and Electrics He'nan University Kaifeng 475004 China Beijing National Laboratory for Molecular Sciences Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

TiO2 colloid was prepared by the sol-gel method and was bladed on transparent conduction glass to made nanoporous electrode. The impedance performance of TiO2 electrode was studied at various bias potential.A simplified equivalent circuit was proposed to investigate the charge transport impedance of TiO2 film and good fitting results were obtained.

关键词： Dye-sensitized solar cell Electrochemical impedance spectroscopy Equivalent circuit Charge transport impedance

Photocatalytic Characterization of TiO_2 Supported on Active Carbon

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Chinese Chemical Letters 2001年第6期12卷 549-550页

作者： Xue Ping LI Feng YIN Yuan LIN jing bo zhang Xu Rui XIAO Laboratory of Photochemistry Center for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100080

The Photocatalytic characterization of TiO2 supported on active carbon was investigated for photocatalytic decomposition of dichloroacetic acid. It was found that TiO2 / AC exhibited a higher photocatalytic activity than pure TiO2. The reason is that active carbon acting as powerful adsorbent supports makes high concentration environments of organic pollutant molecules around TiO2 particles.

关键词： Photocatalysis TiO2 active carbon

Low temperature fabrication of flexible carbon counter electrode on ITO-PEN for dye-sensitized solar cells

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Chinese Chemical Letters 2010年第9期21卷 1137-1140页

作者： Li Li Chen Jia Liu jing bo zhang Xiao Wen Zhou Xiao Ling zhang Yuan Lin Department of Chemistry School of Science Beijing Institute of Technology Beijing 100081 China Beijing National Laboratory for Molecular Sciences Key Laboratory. of Photochemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

A novel low temperature method was used to prepare the mesoporous carbon（MC） counter electrode（CE） on indium-doped tin oxide coated polyethylene naphthalate（ITO-PEN） for flexible dye-sensitized solar cells（DSSCs）.The obtained flexible MC CEs with carbon loading of 280μg cm^（-2） were characterized by SEM,XRD and electrochemical *** light-to-electricity conversion efficiency of the DSSC fabricated with the prepared flexible MC CE was 86%of that of DSSC based on the decomposited Pt CE.

关键词： Mesoporous carbon Flexible counter electrode Dye-sensitized solar cells

Preparation and performance of dye-sensitized solar cells based on ZnO-modified TiO_2 electrodes

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International Journal of Minerals,Metallurgy and Materials 2010年第1期17卷 92-97页

作者： Sheng-jun Li Yuan Lin Wei-wei Tan jing-bo zhang Xiao-wen Zhou Jin-mao Chen Zeng Chen College of Physics and Electrics He＇nan University Kaifeng 475004 China Beijing National Laboratory for Molecular Sciences Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The ZnO-modified TiO2 electrode was prepared by adding Zn（CH3COO）2·2H2O to the TiO2 colloid during the sol-gel production process, and was used in dye-sensitized solar cells （DSCs）. The open circuit voltage （Voc） and fill factor （if） of the cells were improved sig- nificantly. The performances of the ZnO-modified TiO2 electrode such as dark current, transient photocurrent, impedance, absorption spectra, and fiat band potential （Vfb） were investigated. It is found that the interface charge recombination impedance increases and Vfb shifts about 200 mV toward the cathodic potential. The effect mechanism of ZnO modification on the performance of DSCs may be that ZnO occupies the surface states of the TiO2 film.

关键词： dye-sensitized solar cells TiO2 electrode modification photoelectrochemical properties

Communication efficiency optimization of federated learning for computing and network convergence of 6G networks

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Frontiers of Information Technology & Electronic Engineering 2024年第5期25卷 713-727页

作者： Yizhuo CAI bo LEI Qianying ZHAO jing PENG Min WEI Yushun zhang Xing zhang Wireless Signal Processing and Network Laboratory Beijing University of Posts and TelecommunicationsBeijing 100876China Research Institute of China Telecom Co. Ltd.Beijing 102209China Beijing Telecom Beijing 100011China

Federated learning effectively addresses issues such as data privacy by collaborating across participating devices to train global ***,factors such as network topology and computing power of devices can affect its training or communication process in complex network *** and network convergence(CNC)of sixth-generation(6G)networks,a new network architecture and paradigm with computing-measurable,perceptible,distributable,dispatchable,and manageable capabilities,can effectively support federated learning training and improve its communication *** guiding the participating devices'training in federated learning based on business requirements,resource load,network conditions,and computing power of devices,CNC can reach this *** this paper,to improve the communication eficiency of federated learning in complex networks,we study the communication eficiency optimization methods of federated learning for CNC of 6G networks that give decisions on the training process for different network conditions and computing power of participating *** simulations address two architectures that exist for devices in federated learning and arrange devices to participate in training based on arithmetic power while achieving optimization of communication efficiency in the process of transferring model *** results show that the methods we proposed can cope well with complex network situations,effectively balance the delay distribution of participating devices for local training,improve the communication eficiency during the transfer of model parameters,and improve the resource utilization in the network.

关键词： Computing and network convergence Communication efficiency Federated learning Two architectures