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NMR studies of the effects of axial ligand substitution by imidazole on the conformation of cytochrome c

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science china Chemistry 1995年第6期38卷 649-657页

作者：邵伟平姚亦明唐文霞 State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093 China

A series of 1D and 2D 1H NMR studies are presented, which aim at assigning the hyperfine shifted resonances of the heme and the spin systems of more than 20 amino acid side chains, and characterizing the heme and ligand environment of the low spin imidazole complex of cytochrome c. Some details of the structure in the heme pocket of the cytochrome c-imidazole complex are shownqualitatively to have changed relatively to the native oxidized protein. The orientation of the coordinated imidazole is also determined based on the interpretation of a number of NOEs.

关键词： imidazole complex of cytochrome c NMR axial ligand conformation.

Design and measurement of signal processing system for cavity beam position monitor

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Nuclear science and Techniques 2013年第2期24卷 1-6页

作者： WANG Baopeng LENG Yongbin YU Luyang ZHOU Weimin YUAN Renxian CHEN Zhichu Shanghai Institute of Applied Physics Chinese Academy of SciencesJiading campus University of the Chinese Academy of sciences

In this paper,in order to achieve the output signal processing of cavity beam position monitor(CBPM),we develop a digital intermediate frequency receiver architecture based signal processing system,which consists of radio frequency(RF) front end and high speed data acquisition *** beam position resolution in the CBPM signal processing system is superior to 1μ*** signal processing algorithms,fast Fourier transform(FFT) and digital down converter(DDC),are evaluated offline using MATLAB platform,and both can be used to achieve,the CW input signal,position resolutions of 0.31μm and 0.10μm at -16 *** DDC algorithm for its good compatibility is downloaded into the FPGA to realize online measurement,reaching the position resolution of 0.49μm due to truncation *** whole system works well and the performance meets design target.

关键词：信号处理系统位置分辨率在线测量设计目标显示器光束 MATLAB平台信号处理算法

Palaeogeographic Position of the South china Plate During the Early-Middle Devonian

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Acta Geologica Sinica(English Edition) 1991年第1期65卷 19-26页

作者： Bai Zhiqiang Bai Shunliang Department of Geology, Peking University, Beijing Department of Geology Peking University Beijing

In Guangxi, the Lower-Middle Devonian boundary beds yield abundant corals, brachiopods,stromatoporoids and conodonts. The former three were common in tropical and subtropical zones, while thelast occurred only round the equator. This reveals that the South china Plate in the Early-Middle Devonianwas at or near the equator, which was also supported by palaeomagnetic study giving the palaeolatitude of theGuangxi Region at the time to be 0°36′N.

关键词： Palaeogeographic Position of the South china Plate During the Early-Middle Devonian

The nonlinear fixed gravimetric boundary value problem

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science china Chemistry 1995年第5期38卷 596-605页

作者：于锦海朱灼文 Laboratory of Dynamical Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuchang 430077 China Laboratory of Dynamical Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuchang 430077 China)

The properly-posedness of the nonlinear fixed gravimetric boundary value problem is shown with the help of nonlinear functional analysis and a new iterative method to solve the problem is also given, where each step of the iterative program is reduced to solving one and the same kind of oblique derivative boundary value problem with the same type. Furthermore, the convergence of the iterative program is proved with Schauder estimate of elliptic differential equation.

关键词： nonlinear fixed gravimetric boundary value problem properly-posedness iterative program obliquederivative boundary vlaue problem convergence.

Control of Vortex Shedding at Moderate Reynolds Numbers

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china Ocean Engineering 2002年第1期17卷 61-68页

作者：邵传平鄂学全魏庆鼎朱凤荣 Institute of Mechanics Chinese Academy of Sciences State Key Laboratory for Turbulence Study Peking University

The suppression method of vortex shedding from a circular cylinder has been studied experimentally in the Reynolds number range from 300 to 1600. The test is performed in a water channel. The model cylinder is 1 cm in diameter and 38 cm in length. A row of small rods of 0.18 cm in diameter and 1.5 cm in length are perpendicularly connected to the surface of the model cylinder and distributed along the meridian, The distance between the neighboring rods and the angle of attack of the rods can be changed so that the suppression effect on vortex shedding can be adjusted. The results show that vortex shedding can be suppressed effectively if the distance between the neighboring rods is smaller than 3 times and the cylinder diameter and the angle of attack is in the range of 30degreesless than or equal tobeta<90&DEG;.

关键词： control of vortex shedding vortex-induced vibration moderate Re numbers

A new method for preparing ultrafine powders-- Precipitation transformation method

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Chinese science Bulletin 1996年第9期41卷 736-739页

作者：周根陶刘双怀郑永飞 Dept. of Earth and Space sciences Univ. of Sci. and Technol. of China Hefei 230026 China Department of Applied Chemistry Univ. of Sci. Technology of China Hefei 230026 China

The particle sizes of ultrafine powders are between cluster and fine powders, with theparticle diameters generally in the range of 1--100nm. When compared with commonmaterials consisting of bigger particles, materials consisting of nanometer-size particleshave many special properties. These include small-sized effect, surface and interface

关键词： precipitation transformation method ultrafine powders copper (Ⅱ) oxide nickel hydroxide nickel oxide.

RESEARCH ON THE DYNAMIC PROPERTY OF PIEZOELECTRIC MICRO DISPLACEMENT ACTUATOR FOR BORING ERROR COMPENSATION

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Chinese Journal of Mechanical Engineering 2002年第2期15卷 97-102页

作者： Du Zhengchun Yang Jianguo Yao ZhenqiangSchool of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200030, chinaYan JingpingSoutheast University Mechanical Engineering Shanghai Jiaotong University 上海 200030 Southeast University

The dynamic property of piezoelectric micro displacement actuator (PMDA) isanalyzed, especially the mechanical characteristic, lag phase property and hysteresis *** influence factors of static and dynamic mechanical characteristics and the lag phase propertyare analyzed systematically. Three main influence factors of lag phase property are discovered, Withcomparison to mechanical Coulomb friction, a generalized model of nonlinear hysteresis of PMDA isadvanced, based on the essential analysis of nonlinear phenomenon. Finally the application of PMDAin error compensation control system of boring is introduced, A good compensation result isachieved.

关键词： Piezoelectric actuator Dynamic property Lag phase Hysteresis Errorcompensation

An Efficient Way for Glycosylation of Spirostanol

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Chinese Chemical Letters 2005年第5期16卷 593-596页

作者： ShuJieHOU ChuanChunZOU PingShengLEI DeQuanYU InstituteofMateriaMedica PekingUnionMedicalCollege＆ChineseAcademyofMedicalSciencesBeijing100050

Using thioglycosides as donors, trimethylsilyl trifluoromethanesulfonate (TMSOTf) and N-iodosuccinimide(NIS) as promoter, a modified procedure for the glycosylation of spirostanol was developed. A series of saponins w... 详细信息

关键词： Spirostanol glycoside glycosylation trimethylsilyl trifluoromethanesulfonate ethyl 1-thioglycoside N-iodosuccinimide.

INVERSE DYNAMIC FORMULATION OF A NOVEL HYBRID MACHINE TOOL

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Chinese Journal of Mechanical Engineering 2003年第2期16卷 184-189页

作者： XieShunqiang WangJinsong WangLiping LongYunjia ZhangLanxia DepartmentofMathematics&Physics HebeiVocational&TechnicalTeachereCollegeQinhuangdao066004China DepartmentofPrecisionInstruments TsinghuaUniversityBeijing100084China CollegeofBasicsciencesandTechnology ChinaAgriculturalUniversityBeijing100083China DepartmentofMathematics&Physics HebeiVocational&TechnicalTeachersCollegeQinhuangdao066004China

In recent years, hybrid devices have increasingly received more ***, few of researchers studied the dynamic analysis. The inverse dynamic analysis of a novelhybrid machine tool designed in Tsinghua University is presented. The hybrid machine tool underconsideration consists of parallel and serial structures, which is based on a new 2-DOF parallelplatform and serial orientations. The kinematics and the dynamic equations are studied first for theparallel structure through Newton-Euler approach. And then, the dynamic analysis for serialstructures is conducted. Finally, a closed-form inverse dynamic formulation is derived by using someelimination techniques. Some simulation results are also given.

关键词： dynamics parallel manipulator hybrid machine tool