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Nonsolvable Groups with Three Nonlinear Irreducible Character Codegrees

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 173-178页

作者： Dongfang YANG yu zeng Department of Mathematics Changshu Institute of TechnologyChangshu 215500JiangsuChina

For an irreducible characterχof a?nite group G,the codegree ofχis de-?ned as|G:ker(χ)|/χ(1).In this paper,the authors determine?nite nonsolvable groups with exactly three nonlinear irreducible character codegrees,... 详细信息

关键词： Character codegree Nonsolvable group

A　NEW　EMPIRICAL　EQUATION　ON　CORRELATION　BETWEEN　TOPOLOGIC　INDEX　AND　PHYSICO－CHEMICAL　PROPERTIES　OF　NORMAL　PARAFFINS

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Chinese Chemical Letters 1996年第8期7卷 771-772页

作者： Cai Hua NI xian yu zeng ping MEI(Department of Chemistry, JingZhou Teachers’ College Department of Polymer Science, Beijing Universityof Chemical Techology department of Applied Chemistry, Jianghan Petroleum Institute). Department of Chemistry Jingzhou Teachers' College Department of Polymer Science Beijing Univ. of Chemical Technology Department of Applied Chemistry Jianghan Petroleum Institute

An empirical epuation to reveal relations between topological index(ZG)and physico chemical portes of normal paraffins is proposed as follows; p= a ig ZG/Nx + b, where P standsfor a physico-chemical property, N is the number of carbon atoms in the molecule, and ZG is thetopological index proposed by Hosoya a, b, and x are constants related to a certain Phyaicochemical property. Thirteen properties are calculated ac this equation The values of theseproperties caiculated are Close to those from experiments.

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An improved high-fidelity adaptive model for integrated inlet-engine-nozzle based on mechanismdata fusion

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Chinese Journal of Aeronautics 2024年第8期37卷 190-207页

作者： Chen WANG Ziyang yu xian DU Ximing SUN School of Control Science and Engineering Dalian University of TechnologyDalian 116024China Key Laboratory of Intelligent Control and Optimization for Industrial Equipment Ministry of EducationDalian University of TechnologyDalian 116024China

Nowadays,there has been an increasing focus on integrated flight propulsion control and the inlet-exhaust design for the aero-propulsion *** component-level models are inadequate due to installed performance deviations and mismatches between the real engine and the model,failing to meet the accuracy requirements of supersonic *** paper establishes a quasi-one-dimensional model for the inlet-exhaust system and conducts experimental ***,a mechanism-data fusion adaptive modeling scheme using an Extreme Learning Machine based on the Salp Swarm Algorithm(SSA-ELM)is *** study reveals the inlet model’s efficacy in reflecting installed performance,flow matching,and mitigating pressure distortion,while the nozzle model accurately predicts flow coefficients and thrust coefficients,and identifies various operational *** model’s output closely aligns with typical experimental *** combining offline optimization and online adaptive correction,the mechanismdata fusion adaptive model substantially reduces output errors during regular flights and varying levels of degradation,and effectively handles gradual degradation within a single flight ***,the mechanism-data fusion adaptive model holistically addresses total pressure errors within the inlet-exhaust system and normal shock location *** approach significantly curbs performance deviations in supersonic *** example,at Ma=2.0,the system error impressively drops from 34.17%to merely 6.54%,while errors for other flight conditions consistently stay below the 2.95%*** findings underscore the clear superiority of the proposed method.

关键词： Aero-propulsion system Integrated inlet-enginenozzle Component-level model On-board adaptive model Mechanism-data fusion Extreme learning machine

MATHEMATICAL MODEL FOR THERMOKINETICS OF IRREVERSIBLE CONSECUTIVE FIRST ORDER REACTIONS

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Chinese Chemical Letters 1993年第9期4卷 801-804页

作者： Jing Song LIU xian Cheng zeng yu DENG An Min TIAN Department of Chemistry,Sichuan University,Chengdu 610064

The mathematical model for the thermokinetics of irreversible consecutive first order reactions has been suggested,which was used for the calculation of rate constants and molar enthalpies of the two consecutive *** i... 详细信息

关键词： MATHEMATICAL MODEL FOR THERMOKINETICS OF IRREVERSIBLE CONSECUTIVE FIRST ORDER REACTIONS EtOH

Molecules for COVID-19 treatment

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Chinese Chemical Letters 2024年第7期35卷 59-65页

作者： Zhigang zeng Changzhou Liao Lei yu Hubei Key Laboratory of Radiation Chemistry and Functional Materials School of Nuclear Technology and Chemistry&BiologyHubei University of Science and TechnologyXianning 437100China Hubei Industry Technology Research Institute of Intelligent Health Xianning 437100China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

COVID-19 is a major event with worldwide *** the beginning of the epidemic,pharmaceutical chemists have paid attention to the therapeutic effect of a variety of small molecule medicines on COVID-19 infection.A series of organic molecules are designed and found to be effective in the treatment of COVID-19 *** fact,no matter how effective they are,with the development of the COVID-19 epidemic,various small molecule medicines are gradually recognized by *** is equivalent to a good science popularization of pharmaceutical *** review aims to introduce the molecules for COVID-19 treatment on the basis of their chemical structures,synthetic methods as well as their effects.

关键词： COVID-19 Small molecule medicines "Star"drugs Chemical structure Synthetic method

Exploring the Effect of Plasticity on the Phase Imaging of TM-AFM Through Molecular Dynamics Simulations

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Acta Mechanica Solida Sinica 2024年第2期37卷 297-304页

作者： Guolin Liu yu zeng Yaxin Chen Zheng Wei School of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing100029China

In the tapping-mode atomic force microscope(TM-AFM),the probe tip continuously taps the sample surface,which may cause plastic deformation of the sample and result in energy *** energy dissipation of the probe is closely related to the scanned phase *** quantify the energy dissipation due to plastic indentations of the sample,this study utilized a combination of molecular dynamics(MD)simulations and experiments on single-crystal copper samples,including multiple nano-indentation *** energy dissipation of the probe due to the plastic deformation of the sample was calculated by integrating the hysteresis curve of the indentation depth versus the force applied to the *** simulation results are in good agreement with the experimental *** sets of results have demonstrated that the plastic energy dissipation decreases as the number of indentations increases,and eventually the energy of the probe tends to *** equilibrium energy dissipation is associated with other dissipation ***,it was observed that,after hundreds of taps,the dissipated energy of plastic deformation could be ignored,implying that the scanned image may not reflect the plasticity information of the sample after multiple taps of the probe on the sample surface for scanning.

关键词： Atomic force microscopy Force-distance curves Nano-indentations Plasticity Molecular dynamics

Limit Theorems for Critical Galton-Watson Processes with Immigration Stopped at Zero

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Acta Mathematica Sinica,English Series 2024年第2期40卷 435-450页

作者： Dou Dou LI Mei ZHANG xian yu ZHANG College of Statistics and Data Science Faculty of ScienceBeijing University of TechnologyBeijing 100124P.R.China Laboratory of Mathematics and Complex Systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875P.R.China

In this paper,we consider a critical Galton-Watson branching process with immigration stopped at zero *** precise estimation on the probability generating function of the n-th population are obtained,and the tail prob... 详细信息

关键词： Branching immigration critical life period limit theorems

Controlled flight of a self-powered micro blimp driven by insect-sized flapping-wing thrusters

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Chinese Journal of Aeronautics 2024年第6期37卷 127-136页

作者： xian yu Zhiwei LIU Jiaming LENG Mingjing QI Xiaojun YAN School of Energy and Power Engineering Beihang UniversityBeijing 100191China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics Beihang UniversityBeijng 100191China Beijing Key Laboratory of Aero-Engine Structure and Strength Beihang UniversityBeijing 100191China

Micro aerial platforms face significant challenges in achieving long controlled endurance as most of the energy is consumed to overcome the weight of the *** this study,we present a controllable micro blimp that addresses this issue through the use of a helium-filled *** micro blimp has a long axis of 23 cm and is propelled by four insect-sized flapping-wing thrusters,each weighing 80 mg and with a wingspan of 3.5 *** distributed thrusters enable controlled motions and provide the micro blimp with an advantage in flight endurance compared to multirotors or flapping-wing micro aerial vehicles at the same size *** enhance the performance of the controlled flight,we propose a wireless control module that enables manipulation from a distance of up to 100 ***,a smartphone application is developed to send instructions to the circuit board,allowing the blimp to turn left and right,ascend and descend,and achieve a combination of these movements *** findings demonstrate that this micro blimp is one of the smallest controlled self-powered micro blimps to date.

关键词： Microairvehicle Aircraft control Self-powered micro blimp Flapping-wing thruster Wireless flight

Finite Groups with Some Bounded Codegrees

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1778-1784页

作者： Dong Fang YANG yu zeng Heng LV School of Mathematics and Statistics Southwest UniversityChongqing400715P.R.China Department of Mathematics Changshu Institute of TechnologyChangshu215500P.R.China

For a characterχof a finite group G,the number cod(χ) := ∣G:ker(χ)∣/χ(1)is called the codegree ofχ.In this paper,we give a solvability criterion for a finite group G depending on the minimum of the ratioχ(1)^(... 详细信息

关键词： Finite group codegree degree simple group