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The reactions of perfluoroalkanesulfonyl bromide with hetero-atom substituted olefinic bonds

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Acta Chimica Sinica(English Edition) 1988年第2期6卷 150-154页

作者： HUANG Wei-yuan CHEN jian-long Shanghai Institute of Organic Chemistry,Academia Sinica,Shanghai Shanghai Institute of Organic Chemistry Academia Sinica Shanghai

Perfluoroalkanesulfonyl bromides reacted with vinyl bromide,vinyl acetate and trimethylvinyl silane to give the corresponding adducts with the evolution of *** reacted with trimethyl silyl enol ether followed by hydrolysis to give the corresponding α-bromoketones and perfluoroalkanesulfinic ***,perfluoroalkanesulfonyl chlorides reactedwith trimethyl silyl enol ether of pinacolone on UV irradiation to give the corresponding α-perfluo-roalkyl derivatives of *** mild condition,perfluoroalkanesulfonyl bromide alsobrominated phenol and anisole to give the correspondingp-bromo *** α,α-dichloro-trifluoroethanesulfinate reacted with bromine in water at 25℃ to form α,α-dichlorotrifluorcethane-sulfonyl bromide which was thermally less stable than but similar in reactivity to perfluoroalkanesul-fonyl bromide.

关键词： The reactions of perfluoroalkanesulfonyl bromide with hetero-atom substituted olefinic bonds

Modelling and Identification of a Digital Feed Drive

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厦门大学学报（自然科学版） 2002年第S1期41卷 21-22页

作者： LI Sheng, RUAN jian, yuan Ju-long, ZHANG Li-bin, JI Shi-ming (College of Mechanical & Electrical Engineering, Zhejinag University of Technology, Hangzhou 310014, China)

In many cases, the cutting method is usually adopted for the efficient machining of non-circular body of revolution and a feed drive is needed to actuate the cutting tool to and fro according to input signal wave. The feed drive for the purpose is required of fast response and accurate positioning. Both of these are highly dependent upon the actuating elements. Several schemes of actuation are specially interested. One is the introduction of piezoelectric actuation. However, the tiny working stroke of the piezoelectric material limits its application to a narrow range. Another is the application of electro-magnetic actuator. An innovative feed drive actuated by the stepper motor is introduced for the purpose. For a conventional step operating mode, a stepper motor can only be controlled to position at finite discrete points. Thus, when it is applied as an actuator of the feed drive, it is very difficult to maintain high accuracy and fast response. To eliminate quantitative error, the stepper motor is controlled under the continual mode. It is achieved with a micro-controller system and a built-in control algorithm program, called "tracking algorithm". Within each sampling cycle, the micro-controller will sample the input signal and the time interval will be divided into two parts according to the relative position between two adjacent stepping points. The phase coils correspondent to the two adjacent stepping points are energized respectively with calculated time duration. In the way, the motion of the tool frame smoothly tracks the input signal. This paper presents modeling and identification of frequency response of the proposed drive. The dynamic response of the feed drive is manly decided by the natural frequency of the stepper motor. For the conventional small-size stepper motors, the natural frequency is within the range 200～400 Hz. Experimental results show that the stepper motor actuated tool frame can smoothly keep in track of the input signal wave under "t

关键词： feed drive digital control frequency response identification

Analysis of Accuracy of a High-speed Mobile Platform Control System

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厦门大学学报（自然科学版） 2002年第S1期41卷 38-39页

作者： RUAN jian, yuan Ju-long, ZHANG Li-bin, JI Shi-ming, LI Sheng (College of Mechanical & Electrical Engineering, Zhejinag University of Technology, Hangzhou 310014, China)

The efficient manufacture technique involves a high-speed control of platform mobile system. A linear acutor is presented in this paper. The linear acutor is constructed as a linear stepper motor. However, to sustain both high accuracy and high speed for the position and speed control, A single-stack computer system is constructed and a special control algorithm is prescribed to controled the linear actuator continuously. In this paper, the nonlinear errors resulted from the magnetic saturation and the hysteresis is anaysis and discussed. In the view of electromagnetic propotional control, the actuator is a stage proportional magnet, because the driving current to the linear acuator changes for a number of cycles and a series of reset points will occur as the current undergoes cyclic changes. At each reset point the original starting characteristics of the system are re-established. A large number of reset points across the full stroke of the platform results in a significant reduction in the nonlinear behavior. The stage control is first discussed. Experiments carried out to obtain the characteristics of the mobile platform control system. It is demonstrated that with the introduction of stage control, nonlinearities, such as saturation and hysteresis, are greatly reduced, system stiffness is increased, and the positioning accuracy and resolution are improved. The effect of dither due to a "digital fragment" signal is also examined and found to be crucial in reducing the hysteresis and in improving the resolution accuracy.

关键词： high-speed control mobile platform nonlinearities

Development of Squirming Robot for the Inspection of Internal Surface

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厦门大学学报（自然科学版） 2002年第S1期41卷 50-51页

作者： YANG Qing-hua, ZHANG Li-bin, XU Fang, DU Ming-yu, RUAN jian, yuan Ju-long (College of Mechanical & Electrical Engineering, Zhejiang University of Technology, Hangzhou 310032, China)

In many cases, the internal surface of the mechanical elements is required to detect and measure. For this task, a special mobile device should be utilized. A squirming robot is presented for the purpose, which is working on the controlled deformation of a pneumatic columnar elastic shell. This elastic shell is made of caoutchouc. It is strengthened by the internal spiral metal wire, which also restricts its deformation in radial direction, so it can only deform in axis direction. The squirming robot also involves four osculums and a vision system. It can go forward and back and turn around easily by controlling the four osculums and the moving velocity can be controlled through the pressure of compressed air. The moving step can be flexibly adjusted. In this paper, the working principle and mechanical characteristics of the columnar elastic shell are analyzed and discussed in detail. The relationship between the elongation X and the pressure of compressed air P, the bending angular degree θ and the pressure of compressed air P are first established by using the theory of elasticity mechanics. And also we simulate its nonlinear dynamic system in certain diving force F and elastic coefficient E of elastic shell. The results indicate this squirming robot is simple in structure, low cost in manufacture and being apt to be miniaturized. It can be used in detecting the internal surface of mechanical elements or inside certain complicate pipe, when this equipment is manufactured in special, and that this process is able to be fulfilled.

关键词： surface measurement pneumatic squirming robot simulate

SO3■ and sodium perfluoroalkanesulfinate initiated addition of perfluoroalkyl iodide to olefin

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Acta Chimica Sinica(English Edition) 1988年第1期 86-90页

作者： HUANG Wei-yuan CHEN jian-long Shanghai Institute of Organic Chemistry,Academia Sinica Shanghai

The sulfinatodeiodination reagent Ce4+-NaHSO3 was shown to be able to initiate theaddition of perfluoroalkyl iodides to olefins at 50—70℃ to give the corresponding adducts in ***,SO3-generated from Fe3+-NaHSO3 system can also initiate the same addition al-though the reagent is not able to cause *** it was shown that sodiumperfluoroalkanesulfinate is able to initiate the same addition and there is no exchange between theperfluoroalkyl groups of R’FSO2Na and RFI.

关键词： CI CF and sodium perfluoroalkanesulfinate initiated addition of perfluoroalkyl iodide to olefin ppm

Studies on sulfinatodehalogenation Ⅶ.The reaction of perfluoroalkyl iodides with SO3?

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Acta Chimica Sinica(English Edition) 1985年第4期 376-379页

作者： HUANG Wei-yuan CHEN jian-long Shanghai Institute of Organic Chemistry,Academia Sinica,Shanghai

Perfluoroalkyl iodides 1a-1h reacted with sulfite radical anion（SO3-）generated fromthe Ce4+-NaHSO3 system in water-acetonitrile at 70℃ and pH 3—4,to form perfluoroalkyl sulfinates2a-2h,in 70—85% ***,α,ω-perfluo... 详细信息

关键词： Studies on sulfinatodehalogenation The reaction of perfluoroalkyl iodides with SO3 SO

Resistance of Cement-based Grouting Materials with Nano- SiO_(2) Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 114-119页

作者： LI Shuiping CHENG jian WEI Chao yuan Bin YU Chengxiao College of Architectural Science and Engineering Yangzhou UniversityYangzhou 225127China

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction(XRD)and scanning electron microscopy(SEM)of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO_(2) emulsion significantly decreased the compressive strength loss and calcium hydroxide(CH)crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO_(2) particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

关键词： grouting materials nano-SiO_(2)emulsion chloride ion penetration,weight loss strength loss

Numerical simulation of ground motion amplification in Modong area, Lushan

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Applied Geophysics 2019年第3期16卷 277-290,394,395页

作者： Han Chao Yu Jiashun Liu Wei-Zu yuan jian-long Fu Xiao-Bo Hou Xiao-Ping Chengdu University of Technology College of GeophysicsChengdu 610059China

The April 20,2013,Ms 7.0 Lushan Earthquake was a major earthquake that followed the Ms 8.0 Wenchuan Earthquake on May 12,*** earthquakes have caused heavy casualties and property loss in Western *** disasters are often closely related to the amplification effect of ground *** the ground motion characteristics of near-surface geological structures helps to understand the distribution of potential earthquake *** this study,we investigated ground motion amplification in the downtown area of Lushan using numerical simulation and aftershock data from the Lushan *** the Lushan earthquake aftershock data from nine seismic stations distributed in the area,the amplification effect of the sites was determined using the"reference site spectral ratio"*** results show that the frequency of the ground motion amplification in the area was in the range 5–10 Hz,and the corresponding amplification peak was from 3 to *** the study sites,the amplification(14 times)at L07 was the most *** study further the amplification characteristics,shear-wave velocity models for the structures under these sites were established using passive-source Rayleigh surfacewave ***-dimensional(1 D)and two-dimensional(2 D)seismic amplification effects were simulated using horizontally propagating shear-wave *** Site L07,the 1 D simulation results of each site well reflected the variation feature of the seismic amplification on the frequency band below the observed peak frequency,although the overall simulated amplification peaks were smaller than the observed *** 2 D simulation of the remarkable amplification phenomenon at L07 was in better agreement with the observation result than was the 1 D simulation,indicating that the seismic amplification in the Modong area is influenced by lateral variation of the Quaternary sediments.

关键词： Lushan earthquake seismic amplification observation and analysis numerical simulation

Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

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Tungsten 2025年第1期7卷 88-99页

作者： Yu-Jing Weng Zhao-Ying Ding Ying-Chao Li yuan-Feng Wu yuan-Yang Xu Rui Chen Xiao-Lei Zhao Hai-Yong Wang Da-Lei Zhang Yu-long Zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten