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A micromechanical bridge-shaped voltage-controlled oscillator

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Science China(Technological Sciences) 2004年第1期47卷 26-32页

作者： HAN Jianqiang ZHU changchun zhao Hongpo LIU Junhua SHAO Jun Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China

A novel micromechanical bridge-shaped voltage-controlled oscillator with high Q value was fabricated. The core of this kind of oscillators is an electrothermally excited and piezoresistively detected micromechanical bridge resonator. Its resonance frequency can be adjusted by changing the DC voltage applied to the Wheatstone bridge. Theoretical analysis and experimental data show that its resonance frequency is linear with the square of the DC voltage. The linearity is better than 0.16% and the adjustable frequency range excels 17.15%.

关键词： voltage-controlled oscillator, microbridge, resonator, MEMS.

Terahertz frequency characterization of anisotropic structure of tourmaline

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Frontiers of Optoelectronics 2017年第4期10卷 409-413页

作者： Weichong TANG Zili ZHANG Ke XIAO changchun zhao Zhiyuan ZHENG School of Science China University of Geosciences Beijing 100083 China

The absorption coefficient and refractive index of tourmaline in different directions were characterized for the first time using terahertz time-domain spectroscopy. Results show that the absorption and refractive index of terahertz frequency are related to the structure of tourma- line. Absorption along the optical axis direction is more sensitive than that along the vertical direction. This result indicates that the identification and characterization of crystals as well as minerals can be realized by the terahertz method.

关键词： tourmaline optical properties terahertz spectroscopy

Synthesis of Liquid Crystalline Polymers with Side Chains

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Chemical Research in Chinese Universities 1993年第2期9卷 143-147页

作者： YANG Chun-cai , zhao Dong-hui TANG Xin-yi (Department of Chemistry, Jilin University, changchun, 130023)FENG Gui-zen (The Epidemic Preventive Station of Jilin Province, changchun, 130023)zhao Xiao-guang ZHOU En-le (changchun Institute of Applied Chemistry, Academia Sinica, changchun, 130022) He works for post shown degree in changchun Institute of Applied Chemistry, Acaemia Sinica.

The present paper covers the synthesis and characterization of several intermediate products, monomer, and polymers. 3-{ 2-[ 4-( 4-Nitrophenylazo ) phenoxy] ethyloxycarbonyl} propanoyloxy (2-hydroxy) propyl acrylate (4) was prepared by the ring-opening reaction of glycidyl acrylate with the monoester of succinic acid (3). The polymers (5) with different molecular weights were prepared by the free-radical polymerization. The polymers (5) had liquid crystalline behavior without decomposition as revealed by DSC, optical microscope.

关键词： Synthesis Side chain liquid crystalline Free radical polymerization Polymer

CO-DEPOSITION OF Li(Ⅰ)WITH RE(Ⅲ)AND ITS APPLICATION IN THE PRODUCTION OF Al-Li-Cu-RE ALLOY BY MOLTEN SALT ELECTROLYSIS

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Chinese Chemical Letters 1991年第2期2卷 163-166页

作者： Kai Guo CHANG Min Shou zhao changchun Institute of Applied Chemistry,Chinese Academy of Sciences,changchun 130022

The possibility of co-deposition of Li(Ⅰ)and RE(Ⅲ)has been estimated by both theoretical analysis and experimental study on the influences of temperature and concen- tration of chloride on the deposition *** the electrochemical and electrolytic results clearly show that Li(Ⅰ)and RE(Ⅲ)can co-deposit on the Al-Cu electrode under selected conditions.

关键词： Li AND ITS APPLICATION IN THE PRODUCTION OF Al-Li-Cu-RE ALLOY BY MOLTEN SALT ELECTROLYSIS WITH RE Al Cu ITS

Synthesis and Characterization of ChiralLiquid Crystal CMPPCDP

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Chemical Research in Chinese Universities 1994年第3期10卷 202-205页

作者： TIAN Yan-qing , zhao Ying-ying, SU Feng-yu and TANG Xin-yi(Department of Chemistry,Jilin University,changchun,130023)zhao Xiao-guang and ZHOU En-le(Changcnun Institute of Applied Chemistry,Chinese Academy of Sciences,changchun,130022 )

novel chiral liquid crystal4'-( 2-chloro-4methylpentanoyloxy ) phenyl 2-cyano-3-(4' -n-dodecyloxyphenyl)propenoate (CMPPCDP ) was synthesized. The compound was characterized usingIR, ￣1H NNIR, elementary analysis. The liquid crystalline pliasc transition wasstudied using optical polarized micrography and differential scanning calorimetry.

关键词： Liquid crystal Smectic liquid crystal S-1-chloro-4-methyl pentanoiciacid ester

Preparation and Characterization of Chromium ( Ⅲ )-Containing α-and β-Tungstosilicates( Ⅱ )

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Chemical Research in Chinese Universities 1991年第3期7卷 143-147页

作者： Peng Jun and Qu Lunyu (Department of Chemistry, Northeast Normal University, changchun)Xu Yihua (Department of Chemistry, Jilin University, changchun)Peng Weixian and zhao Yongnian (Department of Physics, Jilin University, changchun)

Two new compounds of A- type α-and β-K4.5H2.5[SiW9Cr3(OH2)3O37]·xH2O were synthesized. The two kinds of isomers of α-and β-SiW12-xCrx(x=2, 3) were identified by Second-derivative IR spectroscopy and cyclic voltammetry. The numbers of electrons involved in reductions were obtained by controlled potential electrolyses of the isomers.

关键词： Heteropoly complexes Heteropoly acids Heteropoly anions

Synthesis of Macroporous and High Crosslinking Styrene-Methacryloyloxyphenyl Propane-(bisvinyl-A) Copolymers

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Chemical Research in Chinese Universities 1995年第2期11卷 155-157页

作者： JU Zhi-qiang,WU Tong-hao,YANG Hong-mao,JIANG Yu-zi and TANG Xin-yi (Department of Chemistry,Jilin University,changchun,130023)zhao Bing(Key Laboratory of Molecular Spectrum and Molecular Structure Institute of Theoretical Chemistry,Jilin University,changchun,130023)

Up till now, the crosslinking agent used in the preparation of highcrosslinking polystyrene has usually been divinylbenzene(DVB), which usually results in the crosslinking net structure of styrene-DVB copolymer being uneven. On the contrary, bisvinyl-A has the well compatibility with styrene,which can polymerize to form an even copolvmer, this copolymer has well

关键词： Styrcne Methacryloyioxyphenyl propane (bisvinyl-A) Macroporous structure Synthesis and characterization

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非线性回归支持向量机的SMO算法改进

北京航空航天大学学报 2014年第1期40卷 125-130页

作者：赵长春姜晓爱金英汉北京航空航天大学航空科学与工程学院北京100191 西北工业大学航天学院西安710072

为了解决非线性数据和非线性函数的回归问题,采用了支持向量机序列最小优化算法.原始序列最小优化(SMO,Sequential Minimal Optimization)算法存在训练速度慢和训练结果不稳定的缺点,为了能加快SMO算法的训练速度和提高训练结果稳定性,... 详细信息

为了解决非线性数据和非线性函数的回归问题,采用了支持向量机序列最小优化算法.原始序列最小优化(SMO,Sequential Minimal Optimization)算法存在训练速度慢和训练结果不稳定的缺点,为了能加快SMO算法的训练速度和提高训练结果稳定性,通过改进优化乘子更新方法、采用双阈值法、预存核函数、增加停机准则等方法对SMO算法做了改进.仿真实验表明,改进的算法能很好地对非线性数据和非线性函数进行回归,具有比原始SMO算法更快的训练速度和稳定的训练结果.

关键词：支持向量机回归非线性数据非线性函数序列最小优化算法

Study on the Mode Losses and Bending Lossesof Hollow-core Optical Fiber of GeO2 andSiO2 Bases for Transmitting CO2 Laser Energy

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Chinese Journal of Lasers 1996年第1期 27-32页

作者： HOU Lantian (Department of Physics,Jilin University,changchun 130023 China)SUN Yingzhi (Light Communication Department,changchun Poat and Telecommunication Institte,changchun 130012,China)zhao Bin(Department of Physics,Science and Technology University of

The transmitting losses of several lower modes for four kinds of straight and bent circular hollow optical fibers （waveguide） made up with GeO2 or SiO2 and doped with PbO or Sb2O3 respectively are calculated. The results show that the HE11 mode has the minimum loss in straight waveguide and the loss of TM01 mode in bent waveguide is the minimun.

关键词： hollow-core optical fiber low-order mode bending loss