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3D-QSAR Studies of Dimethoxyphenoxyphenoxy pyrimidines and Analogues

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Chinese Journal of Structural Chemistry 2000年第2期19卷 107-111页

作者： LI Ai Xiu WANG Jin Ling SU Hua Qing MIAO Fang Ming (Institute of Chemical Crystallography, tianjin Normal university, tianjin, 300074) 天津师范大学天津 3 0 0 0 74

Three dimensional quantitative structure activity relationships (3D QSAR) of a series of dimethoxyphenoxyphenoxypyrimidines and analogues which are known to be photosystem Ⅱ(PSⅡ)inhibitors have been studied using comparative molecular field analysis (CoMFA) method. The results suggest that the steric and electronic properties of substitutes at m position on the end phenyl ring have important influence on the Hill reaction inhibition.

关键词： D QSAR photosystem Ⅱinhibitor CoMFA

Upconversion Luminescence Properties and Mechanism of Er^(3+) Doped Ba_(0.65)Sr_(0.35)TiO_3 Ferroelectric Oxide Nanocrystals

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Journal of Wuhan university of technology(Materials Science) 2015年第2期30卷 241-244页

作者：汪竞阳 ZHANG tianjin QU Shaohua ZHONG Zhicheng WANG Song School of Physics and electronic Engineering Hubei University of Arts and Science Hubei key laboratory of Low Dimensional Optoelectronic Materials and devices Hubei University of Arts and Science School of Materials Science and Engineering Hubei University

Ba0.65Sr0.35TiO3（BST） nanocrystals doped with different concentrations of Er^3＋ ion were fabricated using sol-gel method. The structure and morphology of these BST nanocrystals were studied using X-ray diffraction（XRD）, field emission scanning electron microscopy（FESEM） and transmission electron microscopy（TEM）. The X-ray diffraction patterns of all the nanocrystals prepared in the study correspond to polycrystalline perovskite BST structure. The blue and green upconversion luminescence properties of Er^3＋ doped BST nanocrystals were investigated under excitation by a 785-nm laser. The upconversion emission bands centered at 407, 523, and 547 nm can be attributed to ^2H9/2, ^4I15/2, ^2H11/2, ^4I15/2, and ^4S3/2, 4I15/2 transitions of Er^3＋ ion, respectively. The upconversion mechanism was studied in detail, based on the laser power dependence of the upconverted emissions. In addition, we examined the dependence of the intensity of green upconverted luminescence on the doping concentration of Er^3＋ ions, and discussed the mechanism underlying the process.

关键词： Er^3+: BST nanocrystals upconvension luminescence quenching

A Pulse Denoising Method Based on Wavelet Transform

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A Pulse Denoising Method Based on Wavelet Transform

International Conference on Broadcast technology and Multimedia communication(BTMC 2010)

作者： Li Guang-hui The Engineering Training Center tianjin university of technology and Education tianjin china Zhang Xing-hui School of Information technology tianjin university of technology and Education tianjin china

Donnoho et have proposed a method for de-noising by threshold,which has been used in many signal de-noising and compression *** the method of Dohono is not successful for impulsive *** have proposed a method,which detect and wipe off impulse noise,then de-noising by shift-invariant *** results indicate that:it can better detect and reduce the impulsive noise and it can reduce the noise while keeping the signal edges better compared to other wavelet based denoising algorithms.

关键词： impulsive noises wavelet transform shift invariant

Measuring System for Micro Force Based on Electrostatic Theory

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Measuring System for Micro Force Based on Electrostatic Theo...

2009 9th International Conference on electronic Measurement & Instruments（ICEMI’2009）

作者： Yongyue Qi Haitao Wang Yuchi Lin Meirong Zhao (State key laboratory of Precision Measuring technology and Instruments, tianjin university, 300072.tianjin, china )

The micro force measuring technology is widely used in the area of micro friction test, liquid surface tension analysis, organism micro-structure force test, measurement and calibration of MEMS and NEMS, etc. In view of measurement and realization approach of micro force value, a micro measuring system is proposed. A control electrostatic force generator is adopted to reproduce micro force. The basic working principle is an exact designed cylindrical capacitor with the characteristics of long measurement range, fine linearity and faint border effect. A linear axletree with high precision and linearity is used to ensure concentricity of movement. In order to eliminate the interference from parasitical capacitance a hermetical shield is designed. By means of measuring the voltage between electrodes and capacitance change gradient, the micro force test at NN degree could be realized.

关键词： micro force value capacitance change gradient electrostatic force capacitive sensor

Fabrication of Relatively High Growth Rate Microcrystalline Silicon Thin films and Its Application in Solar Cells

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Fabrication of Relatively High Growth Rate Microcrystalline ...

第十五届国际光伏科学与工程大会

作者： Gao Yantao Zhang Xiaodan Zhao Ying Sun Jian Zhu Feng Wei Changchun Wang Yan Han XiaoYan Institute of photo-electronic thin film devices and technology of Nankai university, tianjin 300071, P.R.china key laboratory of Opto-electronic Information Science and technology (Nankai university, tianjin university), Ministry of Education, tianjin 300071, P.R china

Microcrystalline silicon thin films at silane concentration 6%-9% were prepared by VHF-PECVD. The result indicates that dark conductivity decreases with increasing silane concentration, but photosensitivity increases. All microcrystalline silicon thin films are with (220) preferential orientation in this experiment. Finally the solar cells with 6.6% conversion efficiency were fabricated under the deposition rate 5A/s, the responding material with dark conductivity 10S/cm and photosensitivity 1000. There is no ZnO back reflector.

关键词： Microcrystalline Silicon Thin film VHF-PECVD

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基于OAP板卡的网关防病毒技术研究

数字技术与应用 2011年第11期29卷 77-78页

作者：王春东魏俊锋计算机视觉与系统省部共建教育部重点实验室天津300384 天津市智能计算机及软件新技术重点实验室天津300384 天津理工大学计算机与通信工程学院天津300384

由于大部分病毒威胁来自外网,在各个主机上安装防病毒软件虽然能防止病毒对本机的攻击,但并不能阻止病毒在网络上的传播。而在网关处就对病毒进行有效地查杀,可以很好地弥补了基于主机的防毒软件的不足。本文基于网关的病毒查杀思想,在... 详细信息

由于大部分病毒威胁来自外网,在各个主机上安装防病毒软件虽然能防止病毒对本机的攻击,但并不能阻止病毒在网络上的传播。而在网关处就对病毒进行有效地查杀,可以很好地弥补了基于主机的防毒软件的不足。本文基于网关的病毒查杀思想,在H3C公司的MSR系列路由器的OAP板卡来进行病毒防范和隔离研究。实践证明,这样的防病毒卡具有很强的可用性,能够达到更好的防范效果,且易于部署。

关键词：病毒网关防病毒卡

Distributed Arithmetic FIR Filter for Electrical Resistance Tomography System

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Distributed Arithmetic FIR Filter for Electrical Resistance ...

2011 Chinese Control and Decision Conference（CCDC）

作者： Cong Xu is with the tianjin key laboratory of Process Measurement and Control,School of Electrical Engineering and Automation,tianjin university,tianjin,CO 300072,P.R.china.Feng Dong is with the tianjin key laboratory of Process Measurement and Control,School of Electrical Engineering and Automation,tianjin university,tianjin,CO 300072,P.R.china.Zhiqiang Zhang is with the tianjin key laboratory of Process Measurement and Control,School of Electrical Engineering and Automation,tianjin university,tianjin,CO 300072,P.R.china.

The digital FIR filter is widely used in electronic *** is the time delay of the filter that affects the real-time performance of the conventional ERT *** paper discusses the advantages of applying the distributed digital FIR filter in ERT *** with the traditional filter,both the SNR and the channel consistence were improved to some *** importantly,the real-time performance has been improved;especially the data acquisition rate is increased from 600 frames per second to 1040 frames per second for the sixteen electrode system.

关键词： Digital filter FIR Distributed arithmetic ERT

利用空域和时域信息自动分割MPEG-4视频对象

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天津大学学报（自然科学与工程技术版） 2004年第5期37卷 410-413页

作者：鲁照华李华孟伟天津大学电子信息工程学院天津300072

从视频序列中分割出视频对象是实现基于内容压缩编码方法的关键.该文提出了利用空域和时域信息实现MPEG 4视频对象的自动分割方法,利用相邻两帧的帧差和当前帧的纹理、颜色信息及面部定位、梯度滤波等技术,实现目标的初始化,再利用快速H... 详细信息

从视频序列中分割出视频对象是实现基于内容压缩编码方法的关键.该文提出了利用空域和时域信息实现MPEG 4视频对象的自动分割方法,利用相邻两帧的帧差和当前帧的纹理、颜色信息及面部定位、梯度滤波等技术,实现目标的初始化,再利用快速Hausdorff距离法跟踪目标.处理结果表明,该方法对处理相对静止的头肩序列图像具有较强的稳定性,处理速度较快,能取得较好的分割效果.

关键词：视频对象面部定位梯度滤波空域时域 MPEG-4 图象分割图象编码

Fabrication and Characterization of VO_2 Thin films by Direct Current Facing Targets Magnetron Sputtering and Low Temperature Oxidation

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Transactions of tianjin university 2008年第3期14卷 173-177页

作者：梁继然胡明刘志刚韩雷陈涛 School of electronic Information Engineering Tianjin University

Low valence vanadium oxide(VO2-x) thin films were prepared on SiO2/Si substrates at room temperature by direct current facing targets reactive magnetron sputtering, and then proc- essed through rapid thermal annealing. The effects of the annealing on the structure and phase transition property of VO2 were discussed. X-ray photoelectron spectroscopy, X-ray diffraction tech- nique and Fourier transform infrared spectroscopy were employed to study the phase composition and structure of the thin films. The resistance-temperature property was measured. The results show that VO2 thin film is obtained after annealed at 320 ℃ for 3 h, its phase transition tempera- ture is 56 ℃, and the resistance changes by more than 2 orders. The vanadium oxide thin films are applicable in thermochromic smart windows, and the deposition and annealing process is compatible with micro electromechanical system process.

关键词： vanadium dioxide direct current facing targets magnetron sputtering low temperature oxidation: microstructure