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600 Mesh silicon Carbide Corona Protection Varnish with EPOXY/OMMT Nano-composite Adhesive

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Journal of Wuhan University of Technology(Materials Science) 2016年第4期31卷 818-822页

作者：胡春秀 ZHAO yingnan HOU Haibo ZHANG Xiaohong Harbin Research Institute of Large Electric Machinery Harbin 150040 China Key Laboratory of Engineering Dielectrics and Its Application Harbin University of Science and Technology Harbin 150080 China

A new corona protection varnish was prepared by using epoxy/montmorillonite nanocomposite and pure epoxy resin as adhesives *** adhesive with different amounts of organic montmorillonite（OMMT） was mixed with 1200 mesh silicon carbide（si C） by different weight *** surface states of the varnishes with various adhesives were observed by powerful optical *** properties of the varnishes were analyzed during the enduring time under 5kV/cm DC,such as the relation of change in nonlinear coefficient,natural surface resistivity,and surface temperature *** results showed that the amounts of OMMT had little effect on the natural surface resistance of the varnish but had important influence on the nonlinear property of the *** the range of the OMMT content was 2wt% to 6wt%,the nonlinear coefficient of all materials with epoxy/OMMT nano-composite adhesive was higher than that with pure epoxy resin *** surface temperature of the varnish with epoxy/OMMT nanocomposite adhesive was all lower than that with the pure epoxy resin adhesive under high electrical field strength.

关键词： adhesive epoxy Corona resin carbide spacing paint polyester fluctuation powerful

Study the ethanol si/HCCI combustion mode transition by using the fast thermal management system

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Chinese Science Bulletin 2007年第19期52卷 2731-2736页

作者： PENG YaPing TAN ManZhi GUO Liang LIU FaFa LI Hua GUO yingnan Department of Internal Combustion Engine Campus Nanling Jilin University Changchun 130022 China

In this paper the ethanol homogeneous charge compression ignition (HCCI) is achieved in a modified single cylinder engine by means of a self-developed fast thermal management system (FTMS), and the ethanol si/HCCI operation regions are defined. It can be concluded that the thermal efficiency is higher and the NOx emission is lower in the HCCI operation region. In addition, the maximum NOx emission drops by 98%. The ethanol si/HCCI combustion mode transition is conducted in different conditions near the si/HCCI operation boundaries. It is likely to realize the transition by the utilization of FTMS. However, it is impossible to complete the transition within one operating cycle under current operation conditions. There are fluctuations in engine speed and brake mean effective pressure during the transition process. In order to reduce the fluctuations during the transition, the initial work concerning the effects of the spark ignition on the transition smoothness is carried out and the investigation indicates that the engine speed and brake mean effective pressure fluctuations cannot be eradicated only through spark ignition. Therefore, the control strategies combined with other factors should be further optimized.

关键词：电荷压缩点火乙醇燃烧模型火花

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一种像增强器阴极高重频选通电路的设计

应用光学 2022年第6期43卷 1187-1195页

作者：宋海浩延波倪小兵智强李梦依刘佳音任莹楠司可张琳琳微光夜视技术重点实验室陕西西安710065 昆明物理研究所云南昆明650223

就距离选通技术对阴极选通信号要求重复频率高、边沿速度快、脉冲宽度小,提出了一种利用分阶段、多级加速工作的阴极高重频选通电路。通过将RC电路与高速门电路组合构成的时间偏置电路单元相互级联产生不同时序的逻辑脉冲,分别控制中间... 详细信息

就距离选通技术对阴极选通信号要求重复频率高、边沿速度快、脉冲宽度小,提出了一种利用分阶段、多级加速工作的阴极高重频选通电路。通过将RC电路与高速门电路组合构成的时间偏置电路单元相互级联产生不同时序的逻辑脉冲,分别控制中间级驱动金属氧化物半导体场效应晶体管(MOSFET)产生3个阶段性的驱动信号,中间级驱动的输出作为输出级MOSFET的栅极输入,控制其通断过程的加速与保持。利用软件仿真以及板级测试的方式进行了验证,试验结果表明,提出的选通电路可将输出脉冲的边沿时间由μs级提升至2 ns,可提供+50 V/−200 V的阴极关闭/开启电压,实现0~350 kHz的重复频率,0~100%的占空比,3.7 ns的最小脉冲宽度,脉冲输出延时时间抖动在0.1 ns左右。对于提升高速高压选通电源的最小脉冲宽度性能、最高工作重复频率以及降低器件功率损耗具有重要的指导意义。

关键词：像增强器选通电路 MOSFET 高重频

双锥型凹穴微通道超临界CO_(2)流动传热特性研究

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低温工程 2022年第4期 6-13页

作者：陈一航张引弟黄纪琛鞠慧心路达李颖楠司梦婷长江大学石油工程学院武汉430100 油气钻采工程湖北省重点实验室武汉430100

为实现印刷电路板式换热器(Printed circuit heat exchanger,PCHE)中超临界CO_(2)(Supercritical-CO_(2),S-CO_(2))高效低阻强化换热,提出一种基于处理表面强化换热技术的双锥型凹穴矩阵微通道模型。通过数值模拟不同锥体凹穴高径比、... 详细信息

为实现印刷电路板式换热器(Printed circuit heat exchanger,PCHE)中超临界CO_(2)(Supercritical-CO_(2),S-CO_(2))高效低阻强化换热,提出一种基于处理表面强化换热技术的双锥型凹穴矩阵微通道模型。通过数值模拟不同锥体凹穴高径比、环绕型与对称型排列方式对流动传热特性的影响,得到S-CO_(2)在500—850 K范围下,各通道范宁摩阻系数、对流传热系数和综合强化指数等参数随入口流速的变化规律,并引入壁面平均涡强对局部流动与换热机理进行分析。结果发现:对流传热系数随壁面平均涡强的增大而增大,且增加速率随入口速度的增加而增大;环绕型矩阵排列相较于对称型更有利于通道换热;结合综合强化指数,双锥型凹穴结构能实现通道高效低阻强化换热,高径比为2的模型换热性能最优;通过壁面平均涡强对凹穴流动与换热机理的分析,由于双锥型凹穴结构内涡流的增强,平均对流传热系数得到增强,且主要影响边界层附近的流动与换热。

关键词：印刷电路板式换热器超临界 CO_(2) 强化换热数值模拟壁面平均涡强

Light output improvement of GaN-based light-emitting diodes grown on si (111) by a via-thin-film structure

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Journal of Semiconductors 2018年第4期39卷 39-43页

作者： Zengcheng LI Bo Feng Biao Deng Legong Liu yingnan Huang Meixin Feng Yu Zhou Hanmin Zhao Qian Sun Huaibing Wang Xiaoli Yang Hui Yang Key Laboratory of Nanodevices and Applications Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215123 China Lattice Power (Changzhou) Corporation Changzhou 213164 China Lattice Power (Jiangxi) Corporation Nanchang 330029 China Beijing Advanced Materials Development Center Beijing 100083 China

This work reports the fabrication of via-thin-film light-emitting diode （via-TF-LED） to improve the light output power （LOP） of blue/white GaN-based LEDs grown on si （111） substrates. The as-fabricated via-TF-LEDs were featured with a roughened n-GaN surface and the p-GaN surface bonded to a wafer carrier with a silver-based reflective electrode, together with an array of embedded n-type via pillar metal contact from the p-GaN surface etched through the multiple-quantum-wells （MQWs） into the n-GaN layer. When operated at 350 mA, the via-TF- LED gave an enhanced blue LOP by 7.8% and over 3.5 times as compared to the vertical thin-film LED （TF-LED） and the conventional lateral structure LED （LS-LED）. After covering with yellow phosphor that converts some blue photons into yellow light, the via-TF-LED emitted an enhanced white luminous flux by 13.5% and over 5 times, as compared with the white TF-LED and the white LS-LED, respectively. The significant LOP improve- ment of the via-TF-LED was attributed to the elimination of light absorption by the si （111） epitaxial substrate and the finger-like n-electrodes on the roughened emitting surface.

关键词： via thin film LED structure GaN-on-si light-emitting diode light extraction

GaN-based ultraviolet microdisk laser diode grown on si

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Photonics Research 2019年第6期7卷 I0034-I0037页

作者： JIN WANG MEIXIN FENG RUI ZHOU QIAN SUN JIANXUN LIU yingnan HUANG YU ZHOU HONGWEI GAO XINHE ZHENG MASAO IKEDA HUI YANG Key Laboratory of Nano-Devices and Applications Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215123 China University of Science and Technology Beijing Beijing 100083 China Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of SciencesNanchang 330200 China School of Nano Technology and Nano Bionics University of Science and Technology of ChinaHefei 230026 China

This work reports a demonstration of electrically injected GaN-based near-ultraviolet microdisk laser diodes with a lasing wavelength of 386.3 nm at room temperature. The crack-free laser structure was epitaxially grown on si substrates using an Al-composed down-graded Al N/AlGaN multilayer buffer to mitigate the mismatches in the lattice constant and coefficient of thermal expansion, and processed into “sandwich-like” microdisk structures with a radius of 12 μm. Air-bridge electrodes were successfully fabricated to enable the device electrical characterization. The electrically pumped lasing of the as-fabricated microdisk laser diodes was evidenced by the rapid narrowing down of electroluminescence spectra and dramatic increase in the light output power, as the current exceeded the threshold of 248 mA.

关键词： laser diode ultraviolet

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基于液晶偏振光栅的纳米位移测量实验

物理实验 2023年第7期43卷 56-61页

作者：朱梓雯图英楠左一冉司一童张皓祎章恩韬刘通航天工程大学航天信息学院北京101400 航天工程大学宇航科学与技术系北京101400

利用光的偏振特性设计了基于液晶偏振光栅的纳米位移测量实验方案.利用液晶偏振光栅的特性,将两平行放置偏振光栅的横向相对位移转换为入射线偏振光的偏振方向旋转,通过马吕斯定律得到偏振方向转角,计算出的微小位移达到nm量级.

关键词：微小位移偏振液晶偏振光栅马吕斯定律

引入si掺杂层调控InGaAs/GaAs表面量子点的光学特性

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人工晶体学报 2023年第1期52卷 73-82页

作者：刘晓辉刘景涛郭颖楠王颖郭庆林梁宝来王淑芳傅广生河北大学物理科学与技术学院保定071002

在InGaAs/GaAs表面量子点(SQDs)的GaAs势垒层中引入si掺杂层,以研究si掺杂对InGaAs/GaAs SQDs光学特性的影响。荧光发光谱(PL)测量结果显示,InGaAs/GaAs SQDs的发光强烈依赖于si掺杂浓度。随着掺杂浓度的增加,SQDs的PL峰值位置先红移后... 详细信息

在InGaAs/GaAs表面量子点(SQDs)的GaAs势垒层中引入si掺杂层,以研究si掺杂对InGaAs/GaAs SQDs光学特性的影响。荧光发光谱(PL)测量结果显示,InGaAs/GaAs SQDs的发光强烈依赖于si掺杂浓度。随着掺杂浓度的增加,SQDs的PL峰值位置先红移后蓝移;PL峰值能量与激光激发强度的立方根依赖关系由线性向非线性转变;通过组态交互作用方法发现SQDs的PL峰位蓝移减弱;时间分辨荧光光谱显示了从非线性衰减到线性衰减的转变。以上结果说明si掺杂能够填充InGaAs SQDs的表面态,并且改变表面费米能级钉扎效应和SQDs的荧光辐射特性。本研究为深入理解与InGaAs SQDs的表面敏感特性关联的物理机制和载流子动力学过程,以及扩大InGaAs/GaAs SQDs传感器的应用提供了实验依据。

关键词： InGaAs量子点 si掺杂表面费米能级荧光发光谱间接跃迁辐射时间分辨荧光光谱

维普期刊数据库博看期刊

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铁纳米颗粒催化氮化硅粉

硅酸盐学报 2014年第12期42卷 1585-1590页

作者：古亚军曹迎楠李发亮张海军鲁礼林张少伟武汉科技大学省部共建耐火材料与冶金国家重点实验室武汉430081

以Fe纳米颗粒为催化剂,采用催化氮化的方法制备氮化硅。结果表明:加入2%的Fe纳米颗粒,1 350℃保温2h催化氮化后,试样中的残余硅含量小于5%,而相同条件下无催化剂的试样中,单质硅的残余率高达50%。催化氮化制得的si3N4试样中存在大量的... 详细信息

以Fe纳米颗粒为催化剂,采用催化氮化的方法制备氮化硅。结果表明:加入2%的Fe纳米颗粒,1 350℃保温2h催化氮化后,试样中的残余硅含量小于5%,而相同条件下无催化剂的试样中,单质硅的残余率高达50%。催化氮化制得的si3N4试样中存在大量的晶须状si3N4,其直径在40~200nm,长度可达几微米至十几微米。si3N4晶须的生长机理主要为气相--液相--固相机理与固相--液相--气相--固相机理。

关键词：氮化硅铁纳米颗粒晶须催化氮化