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Approach to N-Alkoxy-2-oxoindole for Mimicing SERMs Structure

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Chinese Chemical Letters 2005年第12期16卷 1593-1596页

作者： Ji Cheng chu Dong zhi LIU Hong Sheng GUO Kang ZHAO School of Chemical Engineering and Technology Tianjin University Tianjin 300072 Medical College Chinese People＇s Armed Police Force Tianjin 300071 College of Pharmaceutical and Biotechnology Tianjin UniversityTianjin 300072

Treatment of N-alkoxyamides with bis（trifluoroacetoxy）iodobenzene generated electron deficient nitrogen species, which readily cyclized onto aromatic ring to give N-alkoxy-2- oxoindoles. The effect of different subs... 详细信息

关键词： N-Alkoxyamides bis(trifluoroacetoxy)iodobenzene intramolecular cyclization

Three-dimensional stability of landslides based on local safety factor

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Journal of Mountain Science 2016年第9期13卷 1515-1526页

作者： YANG Tao Man-chu Ronald YEUNG YANG bing LIU Yong-jiang YANG Yan-xin School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China MOE Key Laboratory of Transportation Tunnel Engineering Chengdu 610031China Department of Civil Engineering California State Polytechnic UniversityPomonaCA 91768USA Transportation Research Institute of Chongqing Chongqing 400072China

Unlike the limit equilibrium method(LEM), with which only the global safety factor of the landslide can be calculated, a local safety factor(LSF) method is proposed to evaluate the stability of different sections of a landslide in this paper. Based on three-dimensional(3D) numerical simulation results, the local safety factor is defined as the ratio of the shear strength of the soil at an element on the slip zone to the shear stress parallel to the sliding direction at that element. The global safety factor of the landslide is defined as the weighted average of all local safety factors based on the area of the slip surface. Some example analyses show that the results computed by the LSF method agree well with those calculated by the General Limit Equilibrium(GLE) method in two-dimensional(2D) models and the distribution of the LSF in the 3D slip zone is consistent with that indicated by the observed deformation pattern of an actual landslide in China.

关键词： Landslide stability Local safety factor Stability analysis method Slip mechanism

Single-chip 3D electric field microsensor

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Frontiers of Mechanical Engineering 2017年第4期12卷 581-590页

作者： Biyun LING Yu WANG chunrong PENG bing LI Zhaozhi chu Bin LI Shanhong XIA State Key Laboratory of Transducer Technology Institute of ElectronicsChinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

This paper presents a single-chip 3D electric field microsensor, in which a sensing element is set at the center to detect the Z-axis component of an electrostatic field. Two pairs of sensing elements with the same structure are arranged in a cross-like configuration to measure the X- and Y-axis electrostatic field components. An in-plane rotary mechanism is used in the microsensor to detect the X-, Y-, and Z-axis electrostatic field components simultaneously. The proposed microsensor is compact and presents high integration. The microsensor is fabricated through a MetalMUMPS process. Experimental results show that in the range of 0-50 kV/m, the linearity errors of the microsensor are within 5.5%, and the total measure- ment errors of the three electrostatic field components are less than 14.04%.

关键词： electric field microsensor three-dimensional,single-chip in-plane rotation

Preparation and Structure-Property Regulation Mechanism of Reversible Thermochromic Polydiacetylene

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Chinese Journal of Polymer Science 2024年第8期42卷 1111-1121页

作者： zhi-Qing Ge Shuo Yan Zu-Xiong Pan Shan Lei Xuan-zhi Mao chu Zhao Mo-Zhen Wang Xue-Wu Ge Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Marshall Laboratory of Biomedical Engineering International Cancer CenterLaboratory of Evolutionary Theranostics(LET)School of Biomedical EngineeringShenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The thermochromic mechanism and the structure-property regulation principle of reversible thermochromic polydiacetylene(PDA)materials have always been a challenging *** this work,a series of diacetylene monomers(m-PCDA)containing phenyl and amide or carboxyl groups were synthesized from 10,12-pentacosadiynoic acid(PCDA)through the esterification or amidation *** effects of the number and the distribution of the functional groups in m-PCDA molecules on their solid-state polymerization capability,and the thermochromic mechanism of their corresponding polymers(m-PDA)were investigated and discussed in *** results show that the m-PCDA monomers containing both benzene ring and groups that can form hydrogen bonding interactions have strong intermolecular interaction,and are easy to carry out the solid phase polymerization under 254-nm UV irradiation to obtain the corresponding new thermochromic m-PDA *** thermochromic behavior of m-PDA depends on its melting *** initial color-change temperature(blue to red)is determined by the onset melting tem perature,and the temperature range in which reversible color recovery can be achieved by repeat heating-cooling treatment is determined by its melting *** to the proposed thermochromic mechanism of PDA,various new PDA materials with precise thermochromic temperatu res and reversible thermochromic temperature ra nges can be designed and synthesized through the appropriate introduction of benzene ring and groups that can form hydrogen bonding interactions into the molecular structure of linear diacetylene *** work provides a perspective to the precise molecular structure design and the property regulation of the reversible thermochromic PDA materials.

关键词： Polydiacetylene Thermochromism Hydrogen bonding Chemical modification

The investigation of OH radicals produced in a DC glow discharge by laser-induced fluorescence spectrometry

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Plasma Science and Technology 2021年第6期23卷 12-20页

作者： Feng LIU Yue ZHUANG Haijing chu zhi FANG Wenchun WANG College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816People's Republic of China Key Lab of Materials Modification Dalian University of TechnologyMinistry of EducationDalian 116024People's Republic of China School of Physics and Optoelectronic Technology Dalian University of TechnologyDalian 116024People's Republic of China

In this paper the OH radicals produced by a needle-plate negative DC discharge in water vapor,N_(2)+H_(2)O mixture gas and He+H_(2)O mixture gas are investigated by a laser-induced fluorescence(LIF)*** a ballast resistor in the circuit,the discharge current is limited and the discharges remain in *** OH rotation temperature is obtained from fluorescence rotational branch fitting,and is about 350 K in pure water *** effects of the discharge current and gas pressure on the production and quenching processes of OH radicals are *** results show that in water vapor and He+H_(2)O mixture gas the fluorescence intensity of OH stays nearly constant with increasing discharge current,and in N_(2)+H_(2)O mixture gas the fluorescence intensity of OH increases with increasing discharge *** water vapor and N_(2)+H_(2)O mixture gas the fluorescence intensity of OH decreases with increasing gas pressure in the studied pressure range,and in He+H_(2)O mixture gas the fluorescence intensity of OH shows a maximum value within the studied gas pressure *** physicochemical reactions between electrons,radicals,ground and metastable molecules are *** results in this work contribute to the optimization of plasma reactivity and the establishment of a molecule reaction dynamics model.

关键词： laser-induced fluorescence OH radicals rotational temperature water vapor

3-D rheologic model of earthquake preparation (Ⅱ): Strain field and its applications

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Acta Seismologica Sinica(English Edition) 2004年第2期17卷 131-143页

作者： SONG zhi-ping(宋治平) YIN Xiang-chu(尹祥础) MEI Shi-rong(梅世蓉) Earthquake Administration of Shanghai Shanghai 200062 China Center for Analysis and Prediction China Earthquake Administration Beijing 100036 China Center for Analysis and Prediction China Earthquake Administration Beijing 100036 China

On the basis of the three-dimensional elastic inclusion model, the analytic expression of viscoelastic strain field is derived, i.e., the analytic expression of viscoelastic strain at an arbitrary point (x, y, z) in x-axis, y-axis and z-axis produced by three-dimension inclusion in the semi-infinite rheologic medium defined by the standard linear rheologic model, namely the normal strains exx(r, t), eyy(r, t) and ezz(r, t), the shear strains exy(r, t) and eyx(r, t), eyz(r, t) and ezy(r, t), exz(r, t) and ezx(r, t), and the bulk-strain q (r, t). By computing the spatial-temporal variation of bulk strain on the ground produced by a spherical rheologic inclusion in a semi-infinite rheologic medium, we obtained some significant results that the bulk-strain variation with time produced by a hard inclusion has three stages (a, b, g) with different characteristics, which are similar to those of most geodetic deformation curves, but not the case for those by a soft inclusion. It is meaningful that these theoretical results have been applied to explain preliminarily the characteristics of stage variation of spatial-temporal evolution, the pattern and quadrant distribution of earthquake precursors, the changeability, spontaneity and complexity of short-term and imminent-term precursors. It offers a theoretical base to found the physical model of earthquake precursors and a reference to predict physically the earthquakes.

关键词： elastic inclusion theory rheology inclusion theory strain field analytical solution for viscoelastic problem earthquake precursor

Point-to-Point Iterative Learning Control with Optimal Tracking Time Allocation:A Coordinate Descent Approach 36

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Point-to-Point Iterative Learning Control with Optimal Track...

Isolation of a carbon nanohoop with Mobius topology

第36届中国控制会议

作者： Yiyang Chen bing chu Christopher T.Freeman Electronics and Computer Science University of Southampton

ISBN: (纸本)9781538629185

Iterative learning control(ILC) is a high performance control technique for systems operating in a repetitive manner.A novel design methodology is developed in this paper to incorporate optimal tracking time allocation within the point-topoint ILC framework for discrete time systems. This leads to significant performance improvements compared to fixed time points(e.g. energy reduction). An optimization problem is formulated based on the point-to-point tracking requirement and the via-point temporal constraints. A two stage design framework is proposed to solve this problem, yielding an algorithm based on norm optimal ILC and the coordinate descent method, which automatically minimizes control effort while maintaining high performance tracking. The proposed algorithm is implemented on a gantry robot experimental test platform, with results verifying its practical effectiveness in the presence of model uncertainty.

关键词： iterative learning control optimization coordinate descent method

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Science China Chemistry 2021年第6期64卷 1004-1008页

作者： Zhen-Lin Qiu Dandan Chen Zeying Deng Ke-Shan chu Yuan-zhi Tan Jun Zhu State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Carbon nanohoop,a class of constrained molecular architecture consisting of linked arene units,has attracted considerable interest from both experimental and theoretical chemists due to its synthetic challenge and aesthetic *** fascinating and synthetically challenging species,the Mobius-type molecule,has been attracting the scientific community with its elegant structure and ***,combining two things together,synthesizing a carbon nanohoop with Mobius topology remains more challenging to *** we report a cyclophenylene featuring Mobius strip characterized by X-ray *** calculations reveal that such type of nanohoop is fully conjugated systems with electrons delocalized both inπsextets and the bridging carbon–carbon *** work highlights that the manipulation of phenylene connection in a carbon nanohoop can help obtain more delicate and aesthetic molecular architectures.

关键词： nanohoop cyclophenylene Mobius aromaticity

Vinyltrimethylsilane as a novel electrolyte additive for improving interfacial stability of Li-rich cathode working in high voltage

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Chinese Chemical Letters 2024年第2期35卷 534-538页

作者： bing Jiang Hao Li Bi Luo Lehao Liu Lihua chu Qiaobao Zhang Meicheng Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of New EnergyNorth China Electric Power UniversityBeijing 102206China State Key Laboratory of Physical Chemistry of Solid Surfaces College of MaterialsXiamen UniversityXiamen 361005China

Boosting the interfacial stability between electrolyte and Li-rich cathode material at high operating voltage is vital important to enhance the cycling stability of Li-rich cathode materials for high-performance Li-ion *** this work,vinyltrimethylsilane as a new type of organic silicon electrolyte additive is studied to address the interfacial instability of Li-rich cathode material at high operating *** cells using vinyltrimethylsilane additive shows the high capacity retention of 73.9%after 300 cycles at 1 C,whereas the cells without this kind of additive only have the capacity retention of 58.9%.The improvement of stability is mainly attributed to the additive helping to form a more stable surface film for Li-rich cathode material,thus avoiding direct contact between the electrolyte and the cathode material,slowing down the dissolution of metal ions and the decomposition of the electrolyte under high operating *** findings in this work shed some light on the design of stable cycling performance of Li-rich cathode toward advanced Li-ion batteries.

关键词： Vinyltrimethylsilane Electrolyte additive Li-rich cathode Interfacial stability Capacity retention