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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

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

STUDIES OF MULTICOMPONENT COMPLEX OXIDE CATALYSTS FOR OXIDATIVE COUPLING OF METHANE *** OF CALCINATION TEMPERATURE ON Ti-La-Li PEROVSKITE-TYPE OXIDE CATALYSTS

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Journal of Energy Chemistry 1995年第4期 418-425页

作者： YUAN Song-Yue zhao Zhen changchun institute of Applied Chemistry, Academia Sinica changchun. Jilin 130022YU Zuo-LongChengdu Institute of Organic Chemistry, Academia Sinica Chengdu, Sichuan 610015

The correlations of the calcination *** and catalvtic activity of the LiLaTiOcatalvsts with main phase and major active phase of perovskite-type trmary complex oxide LaTiLiOm the Oxidative coupling of methane（OCM）have been studied The surface and bulk structures of the catalysts were characterized by means of XRD,XPS. *** and so on. The results clearly indicated that the effect of calcination temperature on the activity for the oxidative coupling of methaneis twofold On one *** calcination temperature is favoragble for Lisubstitution for Tiinto the lattice of LaTiOand the production of moreoxygen vacancies at which active oxygen species are formed However,excessivelv high calcmation temperature makes Lisubstitution for Tiless due to a httle change of structure or phases of the catalvst On the otherhand,the conversion of CHdrops because of the decrease of surface area,when the calcination temperature is raised.

关键词： oxidative coupling of methane catalyst calcination temperature titanium-lanthanum-lithium perovskite-type oxide

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层式土壤情况下的阻性耦合

通信学报 1994年第6期15卷 81-85页

作者：赵国谦长春邮电学院

本文分析了层式土壤情况下强电系统与通信系统间的阻性耦合特性，给出了通信设备及其它地下金属管线或埋电缆的金属屏蔽体遭受阻性耦合影响时的地电位计算公式。其结果与均匀土壤情况下所得结果进行比较，表明本文提出的公式用于实际工... 详细信息

本文分析了层式土壤情况下强电系统与通信系统间的阻性耦合特性，给出了通信设备及其它地下金属管线或埋电缆的金属屏蔽体遭受阻性耦合影响时的地电位计算公式。其结果与均匀土壤情况下所得结果进行比较，表明本文提出的公式用于实际工程设计是可行的。

关键词：电磁兼容阻性耦合强电系统通信系统

Bid to host the 2008 Beijing Olympics cross-cultural analysis and dissemination of the value of research

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Bid to host the 2008 Beijing Olympics cross-cultural analysi...

Simulation Analysis of NAPLs Movement in the Subsurface Environment

第五届全国青年体育科学学术会议、第二届中国体育博士高层论坛

作者： HUANG zhao-yuan (changchun teacher's college sports academy Jilin changchun 130032)

1 Foreword The competition to host the Games, is one featuring comprehensive national strength, economic strength, technological power and cultural charm of the competition, is a national image and status competition. Cross-cultural communication with the nature of communication. In the field of culture showing a diversity in film, television, radio and other media columns or programs by different groups

关键词： Bid to host the 2008 Beijing Olympics cross-cultural analysis and dissemination of the value of research

来源： cnki会议评论

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Global Geology 1999年第1期4卷 95-103页

作者： zhao Yongsheng (changchun University of Science & Technology,changchun,130026,China) Wang Baichang (Daqing Petroleum Administrative Bureau,Daqing,163412,China)

Non aqueous phase liquids (NAPLs) pollution are worldwide problems at present. NAPLs which enter the underground through spills or leaks may cause long lasting soil and groundwater contamination problems. Groundwater can be contaminated by non aqueous phase contaminants that are less dense (LNAPL) or denser (DNAPL) than water. The movement of both types of NAPLs will be influenced by the hydrogeological conditions, such as groundwater level, hydraulic conductivity, and porosity etc., however, LNAPL pollutants tend to concentrate at the water table while DNAPL may migrate further down. Understanding the underground migration mechanisms of NAPLs is of primary importance in pollution prediction and site remediation. Several laboratory simulations for NAPLs’ underground movements in porous media have been done in the past (*** et al., 1988, 1989; *** et al., 1995). In this paper, we try to use STOMP (Subsurface Transport Over Multiple Phases) code to simulate the underground migration of NAPLs. The main purposes are: (1). to understand NAPLs’ underground migration mechanisms; (2). to analyze the sensitivities of model parameters, such as hydraulic conductivity, porosity, etc., and to know what are the most sensitive and important parameters in the model application; and (3). to study NAPLs movements in different hydrogeological conditions. The simulations include: Through the computer simulation, we have found that hydraulic conductivity and porosity are very sensitive in the model simulation, small changes of these parameters will cause big difference of the results, therefore, it is essential to accurately determine these parameters for high quality model simulation; The movements of NAPLs in different geological formation are quite different, two different geological media ( clayey sand and sand ) have been chosen in this paper to simulate NAPLs movement with different combinations ( i.e., moving from clayey sand to sand, and from sand to clayey sand ), the

关键词： NAPLs pollution model simulation sensitivity analysis subsurface environment

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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

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东北白头翁属的新变型

植物研究 1989年第4期9卷 69-70页

作者：吉金祥赵毓棠长春中医学院东北师范大学

在调查研究吉林省植物中,1981年在集安县黄柏乡、凉水乡相继发现朝鲜白头翁灰花变型,1982、1986年在同地亦采到标本,并在整理长春中医学院标本中,发现吉林省东丰县亦有分布。

关键词：白头翁属灰花白头翁新变型