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Chinese Journal of Aeronautics 2012年第3期25卷 381-387页

作者： chen wenjuan FAN Wei ZHANG Qun PENG Changxin YUAN cheng YAN Chuanjun School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China

Nozzle effects on thrust and inlet pressure of a multi-cycle air-breathing pulse detonation engine （APDE） are investigated experimentally. An APDE with 68 mm in diameter and 2 050 mm in length is operated using gasoline/air mixture. Straight nozzle, converging nozzle, converging-diverging nozzle and diverging nozzle are tested. The results show that thrust augmentation of converging-diverging nozzle, diverging nozzle or straight nozzle is better than that of converging nozzle on the whole. Thrust augmentation of straight nozzle is worse than those of converging-diverging nozzle and diverging nozzle. Thrust augmentations of diverging nozzle with larger expansion ratio and converging-diverging nozzle with larger throat area range from 20% to 40% on tested frequencies and are better than those of congeneric other nozzles respectively. Nozzle effects on inlet pressure are also researched. At each frequency it is indicated that filling pressures and average peak pressures of inlet with diverging nozzle and converging-diverging nozzle with large throat cross section area are higher than those with straight nozzle and converging nozzle Pressures near thrust wall increase in an increase order from without nozzle, with diverging nozzle, straight nozzle and converging-diverging nozzle to converging nozzle.

关键词： nozzle effect thrust inlet pressure air-breathing pulse detonation engine

Harmonic analysis based on time domain mutual-multiplication window

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Journal of Modern Power Systems and Clean Energy 2016年第1期4卷 47-53页

作者： Tianyuan TAN wenjuan chen Kaipei LIU Niu XIONG Junmin ZHANG Junhua WANG School of Electrical Engineering Wuhan UniversityWuhan 430072China School of Computer Science South-Central University for NationalitiesWuhan 430072China

The signal spectral leakage and fence effect are prone to take place during the power harmonic analysis by fast fourier transform(FFT) under asynchronous *** inhibiting ability of classical window functions is restricted by side-lobe behaviors. A new type window function called time domain mutual-multiplication window, is obtained by multiplication operation of several window functions. A novel approach of harmonic analysis is developed through analyzing performances of main-lobe and side-lobe of the new window. Simulation results show that the time domain mutual-multiplication window can significantly suppress frequency spectral leakage and improve the accuracy of harmonic parameter estimation.

关键词： Mutual-multiplication window Fast Fourier Transform Harmonic Analysis Main-lobe Side-lobe

Effect of inlet-valve structures on thrust of airbreathing pulse detonation engines

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Propulsion and Power Research 2021年第4期10卷 332-346页

作者： wenjuan chen Wei Fan Feiteng Luo Gaohu Tang Yaosong Long School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan430074China School of Power and Energy Northwestern Polytechnical UniversityXi’an710072China

Experimental studies were conducted in order to improve the understanding of the thrust generation and the pressure/flame reverse propagation of the air-breathing pulse detonation engines(APDEs)with self-designed inlets and valves *** present experimental research utilized a gasoline/air APDE(with 68 mm inner-diameter,2050 mm length and maximum operating frequency not less than 40 Hz which was as a benchmark structure)at different operating frequencies,with freestream air inflow of 1.1 atm and 0℃.The theoretical equivalence ratio of gasoline/air was *** kinds of inlets with centerbody or without were considered and combined with two kinds of self-designed valves(the elastic-valve and the convergent aero-valve)specially designed for comparative *** the test,the inflow parameters,the pressure along the longitudinal direction inside the engine and the thrust force were measured for the APDE operating characteristic analysis,including the detonation combustion,the aerodynamic drag,the pressure/flame reverse propagation and the thrust *** research results indicate that:The inlet centerbody does not increase drag but plays a positive effect on airflow stability and operation *** elastic-valve and the convergent aero-valve,though increase the inlet aerodynamic drag,have obvious effects on suppressing the detonation wave and pressure forward propagation,resulting in effective thrust *** of the convergent aero-valve are the best when the flow choked,while the effects of elastic-valve are better and continuously stable in a wider range of *** wmaximum nondimensional thrust increases with the elastic-valve is reached about 1.12 at the frequency of 8-9 Hz,and about 0.97 with the convergent aero-valve at the frequency of 7 *** maximum fuel specific impulse is 2514.6 s when using the convergent *** this study provides technical reserve for the APDE optimization design.

关键词： Air-breathing pulse detonation engine Elastic-valve Convergent aero-valve Thrust augmentation Pressure/flame reverse propagation

Thermodynamic performance modeling,optimization and numerical simulation of RBCC ejector mode

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Propulsion and Power Research 2024年第2期13卷 207-232页

作者： Feiteng Luo Zhenming Qu Yaosong Long wenjuan chen Jinli Hou Baoxi Wei School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan 430074China Science and Technology of Scramjet Laboratory Beijing Power Machinery Research InstituteBeijing 100074China

Ejector mode is a unique and critical phase of wide-range rocket-based combined cycle(RBCC)*** this paper,a quasi-one-dimensional thermodynamic performance modeling method,with more detailed model treatments for the inlet-diffuser system,pri-mary/secondaryflow interaction,and pressure feedback matching,was developed for operating characteristics studies and multi-objective optimization analysis of the ejector mode of an actual RBCC engine.A series of three-dimensional simulations of separate inlet and fullflowpath was completed to validate the modeling study and provide further insight into the operating *** primary/secondary equilibrium pressure ratio functions a significant effect on ejector mode performance,a higher performance augmentation can be obtained by lower rocket pressure ratio,larger mixing section area ratio,smaller throttling throat and higher equivalence ratio,within an appropriate *** positive performance augmentation can be realized at lowflight Mach conditions,the coordination and trade-off relationships between specific im-pulse,performance augmentation ratio and thrust-to-area ratio during ejector mode are present by the Pareto-front from MOP *** is further verified by CFD simulation that,the operating back-pressure at the exit of inlet-diffuser system functions a decisive influence on the airbreathing characteristics,the pressure feedback and matching should be well-controlled for secondaryflowrate and performance *** thermodynamic modeling analysis re-sults are basically consistent with those of numerical simulation,to validate the rationality and effectiveness of the modeling method.

关键词： Rocket-based combined cycle(RBCC) Ejector mode Performance modeling Optimization Numerical simulation

Design of multidimensional nanocomposite material to realize the application both in energy storage and electrocatalysis

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Science Bulletin 2018年第3期63卷 152-154页

作者： Qiancheng Zhu Desheng Cai Xiaoqin Lan Guodong Shi Kai Jin Jianqing Zhou wenjuan chen Ying Yu Institute of Nanoscience and Nanotechnology College of Physical Science and Technology Central China Normal University

The development of clean,sustainable and renewable energy storage systems is in urgent need with the fast-growing energy demand in the areas of electric vehicles and mobile electronics ***-ion batteries(LIBs)have been deemed to be the most promising energy storage devices for their high power density,long cycle life and fast charge-discharge rates[1].Transition

关键词：存储系统精力材料设计应用程序多维锂离子电池存储设备电子学

Synthesis and thermosensitive behavior of dextran graft copolymers containing poly(N-vinylcaprolactam)side chains

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Frontiers of Chemical Science and Engineering 2007年第1期1卷 72-75页

作者： SHI Huangying chen wenjuan ZHANG Liming Institute of Polymer Science School of Chemistry and Chemical Engineering and Key Laboratory for Polymeric Composite and Functional Materials of Ministry of EducationSun Yat-Sen(Zhongshan)UniversityGuangzhou 510275China

New graft copolymers were synthesized by graft-ing N-vinylcaprolactam onto *** composition and structure were investigated by elemental analyses,infrared spectra and thermogravimetric *** optical transmit-tance measurements,it was found that the aqueous solutions of these graft copolymers showed a temperature-dependent transmittance change due to the introduction of thermosensi-tive poly(N-vinylcaprolactam)graft ***,the lower critical solution temperature(LCST)of the graft copolymer in aqueous solution was dependent on its grafting extent and *** LCST value was found to increase with the increase of the grafting extent and decrease with the increase of the copolymer *** these stimuli-response properties,such polysaccharide derivative may hold potential applications in biomedicine and biotechnology.

关键词： intelligent polymers polysaccharide derivative thermosensitive behavior phase transition

Response of spatial structure of cotton root to soil-wetting patterns under mulched drip irrigation

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International Journal of Agricultural and Biological Engineering 2020年第5期13卷 153-162页

作者： Dongwei Li Mingsi Li Xiaojun Shen Xinguo Zhou Hao Sun Yulong Zhao wenjuan chen College of Water Conservancy and Architecture Engineering Shihezi UniversityShihezi 832000XinjiangChina Farmland Irrigation Research Institute Chinese Academy of Agricultural SciencesXinxiang 453002HenanChina

The matching relationship between the spatial structure of cotton cluster root systems and soil-wetting patterns under mulched drip irrigation forms the theoretical basis for the technical design of mulched drip irrigation.A 2-year field experiment was conducted,in which different soil-wetting patterns were produced by setting different emitter discharge *** envelopes of cotton cluster root length densities were derived using the topological methodology and used to examine the effects of different soil-wetting patterns on the spatial structure of root systems and water uptake capacity within row *** results showed that the root systems in rows of cotton grown under narrower and deeper soil-wetting patterns exhibited a single-peak distribution,while those under wider and shallower soil-wetting patterns exhibited a two-peak ***,cotton rows grown near mulch edges experienced lower moisture stress,and wider and shallower soil-wetting patterns contributed to greater root growth rates in the vertical direction and resulted in more even potential water uptake *** findings of this study revealed that wider and shallower soil-wetting patterns were more desirable for mulched drip irrigation of cotton and should be considered in the technical design of drip irrigation systems.

关键词： mulched drip irrigation soil-wetting pattern envelopes of cotton cluster root length densities soil matrix suction potential root water uptake capacity

Reliability analysis method applied in slope stability:slope prediction and forecast on stability analysis

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Global Geology 2006年第2期9卷 239-241页

作者： wenjuan ZHANG Li chen Ning QU Hai＇ an LIANG College of Construction Engineering Jilin University Changchun 130026 China

Landslide is one kind of geologic hazards that often happens ali over the world. It brings huge losses to human life and property; therefore, it is very important to research it. This study focused in combination between single and regional landslide, traditional slope stability analysis method and reliability analysis method. Meanwhile, methods of prediction of slopes and reliability analysis were discussed.

关键词： landslide prediction reliability

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古典共和传统中的公民教育及其启示

教育研究 2016年第8期37卷 145-151页

作者：陈文娟中央财经大学马克思主义学院

西方古典共和传统中的公民教育,从教育目标上讲是一种旨在培养良善公民的德性教育。从实施途径来讲,包括公共教育和家庭教育两种模式。在当今社会,古典共和传统的公民教育对于反思西方现代所谓"民主教育"之弊端有一定启示。

关键词：共和主义公民教育德性教育民主教育

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重申德性:建构一种现代共和主义德性论

政治学研究 2019年第5期 48-57,126,127页

作者：陈文娟中央财经大学马克思主义学院

自由主义德性论试图从内部对主流的自由主义中立性学说进行矫正,但其本身缺乏足够的理论资源,又囿于自由主义的既定框架,其调整空间有限;而在当代共和主义复兴中占据主导地位的工具论共和主义则试图从外部借助“无支配自由”对自由主义... 详细信息

自由主义德性论试图从内部对主流的自由主义中立性学说进行矫正,但其本身缺乏足够的理论资源,又囿于自由主义的既定框架,其调整空间有限;而在当代共和主义复兴中占据主导地位的工具论共和主义则试图从外部借助“无支配自由”对自由主义展开批判,但未能充分发掘古典共和主义的德性传统,结果与自由主义拉不开足够的距离,几乎沦为某种改良版的自由主义。本文借助西方当代政治哲学中相关争论,试图勾勒一种现代共和主义德性论的理论纲要,从国家在塑造政治德性方面的作用、对不同政治主体的特定德性要求,以及培养政治德性的社会机制与心理机制三个方面,主张以温和至善论重建国家与公民的良性互动关系,以新型德性论继承、转化和发展传统的政治德性,以有效的公民教育培养有德性的公民,展现这种现代共和主义德性论的基本面向。

关键词：德性自由主义中立性自由主义德性论工具论共和主义共和主义德性论