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A novel solid state Michael addition reaction of N-heterocyclic compounds containing active C-H bond

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Chinese Journal of Chemistry 1996年第5期14卷 421-427页

作者： Li, XL Wang, YM Tian, B meng, jb NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

In this paper, a novel solid state Michael-type addition reaction of N-heterocyclic compounds containing the active-CH group was investigated. 3-Methyl-1-phenyl-5-pyrazolone (MPP) and indole (In) reacted with 4-arylmethylene-3-methyl-1-phenyl-5-pyrazolone (1) in the solid state at room temperature to give the corresponding adducts, aryl-4,4'-bis(5-hydroxy-3-methyl-1-phenyl-pyrazolyl) methane (2a-n) and 1-aryl-1-(5'-hydroxy-3'-methyl-1'-phenyl-4'-pyrazolyl)-1-(3 ''-indolyl) methane (3a-n), respectively. This is a feasible method for preparing the compound which contains two heterocyclic groups on the same carbon.

关键词： indole pyrazolone Michael addition solid state reaction

Synthesis and photochromism of dimers of 4,5- diaryl-2-(2,5-dimethylthiophen-3-yl)imidazolyl

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Chinese Journal of Chemistry 1997年第6期15卷 553-555页

作者： Bai, JQ Han, XC Wang, YM meng, jb Nankai Univ Dept Chem Tianjin 300071 Peoples R China

4,5-Diphenyl, 4,5-di(4-methylphenyl), 4,5-di(4-methoxyphenyl)-2-(2,5-dimethylthiophen-3-yl)imidazoles were synthesized. Oxidation of the obtained imidazoles with potassium ferricyanide in water-alcohol solution of alkali gave the corresponding dimers. The structures were characterized by IR, H-1 NMR, mass spectroscopy and elemental analysis. The dimers showed photochromism in solution on irradiation.

关键词： synthesis imidazoles dimers photochromism

Synthesis of new heterocycles 1,3,2,6-dioxaphosphaselenacyclooctanes

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Chinese Journal of Chemistry 1997年第5期15卷 450-458页

作者： Li, JL Tian, B Zhao, CQ Wang, YM meng, jb Wang, HG Nankai Univ Dept Chem Tianjin 300071 Peoples R China Nankai Univ Cent Lab Tianjin 300071 Peoples R China

New phosphorus-and selenium containing heterocyclyes, 1,3,2,6-dioxaphosphaselena-cyclooctanes (1a-1h), were synthesized by the reaction of bis(2-hydroxyethyl)selenide with RP(X)Cl-2 where R=alkoxyl, aroxyl, aryl. and X=O or lone pair. Their structures were determined by spectroscopies and elemental analyses and finally confirmed by the X-ray crystallographic analysis of 1c. The molecular structures of the heterocycles were discussed in term of conformational analysis.

关键词： heterocycles synthesis structure

A vertical track nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 931-946页

作者： meng LI Hu DING Shanghai Key Laboratory of Mechanics in Energy Engineering School of Mechanics and Engineering ScienceShanghai Frontier Science Center of MechanoinformaticsShanghai UniversityShanghai 200444China

Eliminating the effects of gravity and designing nonlinear energy sinks(NESs)that suppress vibration in the vertical direction is a challenging task with numerous damping *** this paper,the dynamic design of a vertical track nonlinear energy sink(VTNES)with zero linear stiffness in the vertical direction is proposed and realized for the first *** motion differential equations of the VTNES coupled with a linear oscillator(LO)are *** the strong nonlinearity considered of the VTNES,the steady-state response of the system is analyzed with the harmonic balance method(HBM),and the accuracy of the HBM is verified *** this basis,the VTNES prototype is manufactured,and its nonlinear stiffness is *** damping effect and dynamic characteristics of the VTNES are studied theoretically and *** results show that the VTNES has better damping effects when strong modulation responses(SMRs)***,even for small-amplitude vibration,the VTNES also has a good vibration suppression *** sum up,in order to suppress the vertical vibration,an NES is designed and developed,which can suppress the vertical vibration within certain ranges of the resonance frequency and the vibration intensity.

关键词： track nonlinear energy sink(TNES) vertical direction gravity nonlinear stiffness harmonic balance method(HBM) vibration control

Nested Saturated Control of Uncertain Complex Cascade Systems Using Mixed Saturation Levels

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1163-1174页

作者： meng Li Zhigang Zeng Wuhan National Laboratory for Optoelectronics Wuhan 430074 School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074 Key Laboratory of Image Processing and Intelligent Control of Education Ministry of China Wuhan 430074China

This study addresses the problem of global asymptotic stability for uncertain complex cascade systems composed of multiple integrator systems and non-strict feedforward nonlinear systems. To tackle the complexity inherent in such structures, a novel nested saturated control design is proposed that incorporates both constant saturation levels and state-dependent saturation levels. Specifically, a modified differentiable saturation function is proposed to facilitate the saturation reduction analysis of the uncertain complex cascade systems under the presence of mixed saturation levels. In addition, the design of modified differentiable saturation function will help to construct a hierarchical global convergence strategy to improve the robustness of control design scheme. Through calculation of relevant inequalities, time derivative of boundary surface and simple Lyapunov function,saturation reduction analysis and convergence analysis are carried out, and then a set of explicit parameter conditions are provided to ensure global asymptotic stability in the closed-loop systems. Finally, a simplified system of the mechanical model is presented to validate the effectiveness of the proposed method.

关键词： method saturation differentiable

Adaptive admittance tracking control for interactive robot with prescribed performance

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Journal of Systems Engineering and Electronics 2024年第2期35卷 444-450页

作者： meng Qingrui LIN Yan School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100190China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China

An adaptive control approach is presented in this paper for tracking desired trajectories in interactive manipulators. The controller design incorporates prescribed performance functions (PPFs) to improve dynamic performance. Notably, the performance of the output error is confined in an envelope characterized by exponential convergence, leading to convergence to zero. This feature ensures a prompt response from admittance control and establishes a reliable safety framework for interactions. Simulation results provide practical insights,demonstrating the viability of the control scheme proposed in this paper.

关键词： prescribed performance admittance control adaptive control robots

MICROENVIRONMENTAL　EFFECT　ON　THE　INTRAMOLECULAR　PHOTOCHEMICAL　INTERACTION　OF　BIS－COUMARINYL　COMPOUNDS　CONTAINING　ALKYL　CHAINS

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Chinese Chemical Letters 1996年第8期7卷 753-755页

作者： Gao, H Wang, GC Liang, LJ He, BL Du, DM Wang, YM meng, jb NANKAI UNIV STATE KEY LAB POLYMER MAT ADSORPT & SEPARATTIANJIN 300071PEOPLES R CHINA NANKAI UNIV INST POLYMER CHEMTIANJIN 300071PEOPLES R CHINA NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

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ＭＩＣＲＯＥＮＶＩＲＯＮＭＥＮＴＡＬ　ＥＦＦＥＣＴ　ＯＮ　ＴＨＥ　ＩＮＴＲＡＭＯＬＥＣＵＬＡＲ　ＰＨＯＴＯＣＨＥＭＩＣＡＬ　ＩＮＴＥＲＡＣＴＩＯＮ　ＯＦ　ＢＩＳ－ＣＯＵＭＡＲＩＮＹＬ　ＣＯＭＰＯＵＮＤＳ　ＣＯＮＴＡＩＮＩＮＧ　ＡＬＫＹＬ　ＣＨＡＩＮＳ...

关键词： BIS COUMARINYL OF INTERACTION CHAINS ALKYL

Cooperative User-Scheduling and Resource Allocation Optimization for Intelligent Reflecting Surface Enhanced LEO Satellite Communication

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China Communications 2024年第2期21卷 227-244页

作者： meng meng Bo Hu Shanzhi Chen Jianyin Zhang State Key Lab of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Lab of Wireless Mobile Communication China Academy of Telecommunication TechnologyBeijing 100191China Research Institute of China Mobile Beijing 100053China

Lower Earth Orbit(LEO) satellite becomes an important part of complementing terrestrial communication due to its lower orbital altitude and smaller propagation delay than Geostationary satellite. However, the LEO satellite communication system cannot meet the requirements of users when the satellite-terrestrial link is blocked by obstacles. To solve this problem, we introduce Intelligent reflect surface(IRS) for improving the achievable rate of terrestrial users in LEO satellite communication. We investigated joint IRS scheduling, user scheduling, power and bandwidth allocation(JIRPB) optimization algorithm for improving LEO satellite system *** optimization problem of joint user scheduling and resource allocation is formulated as a non-convex optimization problem. To cope with this problem, the nonconvex optimization problem is divided into resource allocation optimization sub-problem and scheduling optimization sub-problem firstly. Second, we optimize the resource allocation sub-problem via alternating direction multiplier method(ADMM) and scheduling sub-problem via Lagrangian dual method ***, we prove that the proposed resource allocation algorithm based ADMM approaches sublinear convergence theoretically. Finally, we demonstrate that the proposed JIRPB optimization algorithm improves the LEO satellite communication system throughput.

关键词： convex optimization intelligent reflecting surface LEO satellite communication OFDM

Identifying Comprehensive Genomic Alterations and Potential Neoantigens for Cervical Cancer Immunotherapy in a Cohort of Chinese Squamous Cell Carcinoma of the Cervix

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Biomedical and Environmental Sciences 2024年第6期37卷 565-580页

作者： meng Wu Jialu Zhou Zhe Zhang Yuanguang meng School of Medicine Nankai UniversityTianjin 300071China Department of Obstetrics and Gynecology The First Medical Center of Chinese PLA General HospitalBeijing 100853China Department of Obstetrics and Gynecology Chinese PLA Medical SchoolBeijing 100853China Department of Obstetrics and Gynecology The Seventh Medical Center of Chinese PLA General HospitalBeijing 100700China

Objective Genomic alterations and potential neoantigens for cervical cancer immunotherapy were identified in a cohort of Chinese patients with cervical squamous cell carcinoma(CSCC).Methods Whole-exome sequencing was used to identify genomic alterations and potential neoantigens for CSCC *** Sequencing was performed to analyze neoantigen *** Systematic bioinformatics analysis showed that C>T/G>A transitions/transversions were dominant in *** mutations were the most frequent types of somatic mutation in the coding sequence *** signature analysis detected signature 2,signature 6,and signature 7 in CSCC ***3CA,FBXW7,and BICRA were identified as potential driver genes,with BICRA as a newly reported *** variation profiling identified 4,960 potential neoantigens,of which 114 were listed in two neoantigen-related *** The present findings contribute to our understanding of the genomic characteristics of CSCC and provide a foundation for the development of new biotechnology methods for individualized immunotherapy in CSCC.

关键词： Cervical squamous cell carcinoma Genome alteration Neoantigens Immunotherapy