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Electrodeposition and Characterization of Ni/Ti_3Si(Al)C_2 Composite Coatings

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Journal of Materials Science & Technology 2011年第11期27卷 1016-1024页

作者： Ying Liang Mingyue Liu jixin chen Xiaoxia Liu Yanchun Zhou Department of Chemistry Northeastern University Shenyang 110819 China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Pure nickel and Ni/Ti3Si（AI）C2 composite coatings were prepared by electrodeposition method from an additive-free nickel Watt＇s bath and were characterized by X-ray diffraction, laser confocal microscopy and scanning electron microscopy. The effect of current and Ti3Si（AI）C2 concentration in the solution on the composition, grain size, preferred orientation and surface morphology of the electrodeposited coatings were investigated. （200）-oriented Ni coatings could be deposited at high current （62.5 mA）, while （220）-oriented Ni coatings could be obtained at low current （25 mA）. However, the presence of Ti3Si（Al）C2 particles disturbed the surface texture of Ni crystallites in the composite coatings. Based on the simulated morphology and the observed microstructure, the mechanisms for the change of preferred orientation and crystallite shapes in the presence of Ti3Si（Al）C2 particles were discussed. Moreover, microhardness and friction properties of pure nickel and Ni/Ti3Si（Al）C2 composite coatings were also compared.

关键词： Ni/TiaSi(Al)C2 composite coatings Electrodeposition Preferred orientation Microstructure Mechanical properties

Microstructure and mechanical properties of h-BN/Yb_4Si_2O_7N_2 composites

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Journal of Advanced Ceramics 2018年第4期7卷 317-324页

作者： Juanjuan chen jixin chen Hao ZHANG Minmin HU Meishuan LI Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences University of Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

A series of h-BN based composites with Yb_4Si_2O_7N_2 as a secondary phase were successfully synthesized by an in situ reaction hot pressing method. It was found that the relative density and room-temperature mechanical properties monotonically increased with increasing the content of Yb_4Si_2O_7N_2 from 20 to 50 vol%. When 50 vol% Yb_4Si_2O_7N_2 was introduced, the relative density of the composite reached 98.75%, and its flexural strength, compressive strength, fracture toughness, and hardness reached 338±10 MPa, 803±49 MPa, 2.06±0.06 MPa·m1/2, and 2.69±0.10 GPa, respectively. The strengthening effect of Yb_4Si_2O_7N_2 was mainly attributed to its high modulus and high hardness. Fine microstructure was also advantageous to strength and could lead to more tortuous crack propagation paths and then improve the fracture toughness of the composites simultaneously. Meanwhile, the composites maintained good machinability.

关键词： h-BN/Yb_4Si_2O_7N_2 composites microstructure mechanical properties machinability

Stabilization of mixed-halide lead perovskites under light by photothermal effects

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Journal of Energy Chemistry 2021年第12期30卷 8-11,I0001页

作者： Juvinch R.Vicente Martin E.Kordesch jixin chen Department of Chemistry and Biochemistry Ohio UniversityAthensOH 45701United States Nanoscale and Quantum Phenomena Institute Ohio UniversityAthensOH 45701United States Department of Chemistry University of the Philippines VisayasMiagaoIloilo 5023Philippines Department of Physics and Astronomy Ohio UniversityAthensOH 45701United States

Mixed-halide lead perovskites(MHLPs) are semiconductor materials with bandgaps that are tunable across the visible spectrum and have seen promising applications in photovoltaics and ***, their segregation into phases with enriched halide components, under resonant light illumination and/or electric field, have hindered their practical applications. Herein, we demonstrate the stabilization of the MHLP photoluminescence(PL) peak as a function of their excitation *** effect is associated with the phase segregation of MHLPs and their subsequent remixing by photothermal heating. We conclude that the balance between these opposing processes dictates the equilibrium PL peak of the MHLPs. The findings in this work could serve as a potential approach to obtain MHLP with stable emission peaks under operating conditions.

关键词： Perovskites Phase segregation Photothermal Solar cells LEDs

A W-band wideband power amplifier using out-of-phase divider in 0.13-μm SiGe BiCMOS

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Science China(Information Sciences) 2018年第12期61卷 223-225页

作者： Debin HOU Wei HONG jixin chen Zhe SONG State Key Laboratory of Millimeter Waves Southeast University

Dear editor,More and more researchers focus on millimeterwave applications for the resourceful unlicensed or light licensed frequencies such as 60 GHz, E-band(71–76 GHz and 81–86 GHz) for high data-rate communications, and 77/79 GHz, 94 GHz, and122 GHz for automotive radar and imaging applications. As an important component of the sys-

关键词： A W-band wideband power amplifier using out-of-phase divider in 0.13 m SiGe BiCMOS

A SiGe W-band frequency tripler with 10.5 dBm output power using harmonic suppression technique

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Science China(Information Sciences) 2022年第4期65卷 285-286页

作者： Huanbo LI jixin chen Peigen ZHOU Debin HOU Wei HONG State Key Laboratory of Millimeter Waves Southeast University Purple Mountain Laboratory

Dear editor,The rapid development of silicon-based process has motivated great attention in mm-wave applications. Recently,W-band frequencies have become an appealing choice for various wireless applications, such as ... 详细信息

关键词： SiGe W-band frequency triper harmonic suppression transformer

Photonic sensor with radio frequency power detection for body pressure monitoring

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Optoelectronics Letters 2023年第12期19卷 752-755页

作者： ZHAO Zhiying chen jixin YANG Jieqing JIANG Quan Sichuan Provincial People's Hospital University of Electronic Science and Technology of ChinaChengdu 610072China Institute for Cyber Security University of Electronic Science and Technology of ChinaChengdu 611731China School of Optoelectronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu610054China

A photonic sensor with radio frequency(RF)power detection for body pressure monitoring is *** sensor based on two fiber Bragg gratings(FBGs)can transfer the wavelength shift to the change of RF *** pressure can be measured by modulating and processing one single frequency RF *** theoretical analysis and experimental results of the photonic sensor are presented and *** pressure sensitivities are acquired with 2.62×10^(−5)mW/kPa at 2.14 GHz,2.46×10^(−5)mW/kPa at 2.21 GHz,2.81×10^(−5)mW/kPa at 2.37 GHz,and 3.02×10^(−5)mW/kPa at 2.45 GHz,***,the pressure measurements of pressed body parts are also obtained by the sensor.

关键词： power frequency fiber

A Low Power,High Sensitivity SiGe HBT Static Frequency Divider up to 90 GHz for Millimeter-Wave Application

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China Communications 2019年第2期16卷 85-94页

作者： Peigen Zhou jixin chen Pinpin Yan Debin Hou Wei Hong State Key Laboratory of Millimeter Waves Southeast University

A layout and connection optimization for static frequency divider is presented. The layout optimization provides a new circle topology transistors placement and reasonable connection structure, which reduces the parasitic effectively and enables self-oscillation frequency enhancement. Besides, bandwidth enhancement techniques based on a center-tap capacitor in input balun design and inductive peaking in latch design are adopted to improve further high frequency performance with low power consumption. As a proof of concept, design of a divide-by-2 static frequency divider in 0.13 μm SiGe BiCMOS technology is reported. With single-ended input clock signal, the divider is measured to be operated from 40 to 90 GHz. Phase noise measurements of a 90 GHz input clock signal indicate ideal behavior with no measurable noise contribution from the divider. The divider followed by a buffer that can deliver more than-10 dBm output power, which is sufficient to drive succeeding stage. To the author's knowledge, the divider exhibits a competitive power dissipation and the highest FOM among silicon based frequency dividers that operating higher than 70 GHz.

关键词： E-band layout optimization millimeter wave integrated circuits static frequency divider SiGe

IEEE 802.11aj(45GHz):A New Very High Throughput Millimeter-Wave WLAN System

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China Communications 2014年第6期11卷 51-62页

作者： WANG Haiming HONG Wei chen jixin SUN Bo PENG Xiaoming State Key Laboratory of Millimeter Waves Southeast University Strategy Planning Development ZTE Cooperation Institute for InfocommResearch(I2R)

This paper presents an overview of a new very high throughput millimeterwave WLAN system operating at 45 GHz band. We begin by reviewing standards process of IEEE 802.11aj(45GHz). Then the frequency spectrum allocation at 45 GHz band is introduced. Next, the channel measurement and mod-eling is given. Specifically, the millimeter-wave MIMO for physical layer enhancement is given in detail.

关键词： wireless local access network(WLAN) millimeter-wave very highthroughput 45 GHz mul-tiple-input andmultiple-output (MIMO)

A high-efficiency, high harmonic rejection E-band SiGe HBT frequency tripler for high-resolution radar application

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Science China(Information Sciences) 2019年第6期62卷 183-185页

作者： Peigen ZHOU Pinpin YAN jixin chen Debin HOU Wei HONG State Key Laboratory of Millimeter Waves Southeast University

Dear editor,With the advances in silicon-based technologies,high performance, low-cost frequency-modulated continuous wave (FMCW) radar sensors enabling advanced driver-assistance convenience in vehicles have been developed extensively in recent years [1]. Multi-mode sensors which support both long-range at 76 to 77 GHz and short-range at 77

关键词： Figure high harmonic rejection E-band SiGe HBT frequency tripler for high-resolution radar application A high-efficiency