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A miniaturized mechanical antenna based on FEP/ THV unipolar electrets for extremely low frequency transmission

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Microsystems & Nanoengineering 2022年第3期8卷 223-233页

作者： yong Cui Ming Wu Zhaoyang Li Xiao Song Chen Wang Haiven yuan Zhi-Xin Yang Junwen zhong School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Department of Electromechanical Engineering and Centre for Artificial Intelligence and Robotics University of MacaoMacaoSAR 999078China School of Cyber Science and Technology Beihang universityBeijing 100191China State Key Laboratory of Internet of Things for Smart City and Department of Electromechanical Engineering University of MacaoMacaoSAR 999078China

An electret-based mechanical antenna(EBMA),which can transmit extremely low frequency(ELF)electromagnetic signals,has the advantages of miniaturization and high transmitting efficiency,with great potential applications in air,underwater,and underground *** improve the charge density of the electret,which is a key factor in determining the radiation performance of an EBMA,this work proposes a fluorinated ethylene propylene/terpolymer of tetrafluoroethylene,hexafluoropropylene and vinylidene fluoride(FEP/THV)unipolar electret exhibiting negative polarity,reaching a total charge density up to-0.46 mC/m^(2) for each layer of *** transmission distances can be achieved in sea water,soil,and air using a 3-layer-FEP/THV-based EBMA with a compact volume of 5×10^(-4) m^(3).As an application demonstration,binary ASili-coded ELF information of"BUAA"is successfully transmitted with a power consumption<5W.

关键词： antenna propylene FEP

CRYSTALLINE MORPHOLOGY IN A SERIES OF CH_(3)-SUBSTITUTED THERMOTROPIC AROMATIC POLYESTERS WITH EVEN AND ODD FLEXIBLE SPACERS

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Chinese Journal of Polymer Science 2001年第1期19卷 71-78页

作者： Shou-xi Chen zhong-ming Hu Wen-hui Song yong-ze Jin Ren-yuan Qian State Key Laboratory of Polymer Physics and Chemistry Center for Molecular ScienceInstitute of ChemistryChinese Academy of SciencesBeijing 100080China

Crystalline morphology in a series of CH_(3)-substituted main chain thermotropic aromatic polyesters with even and odd numbered methylene spacers has been studied by polarizing optical microscopy(POM),scanning electron microscopy(SEM)and transmission electron microscopy(TEM).On crystallization from solution evaporation spherulites of radial structure were observed in the polymers with even numbered spacers,but spherulites with concentric rings form in the polymer with odd numbered *** spherulites have a lamellar structure,which is about 10 nm in *** crystallization from nematic glassy state spherulites can not be grown;lamellar structure was only observed around disclinations in a specimen during *** the case of crystallization from nematic melt two types of spherulites can be observed far the sample with even numbered *** the sample with add numbered spacers spherulites can not be formed,but only irregular crystallites.

关键词： crystalline morphology spherulite even-odd flexible spacers CH_(3)-substituted thermotropic aromatic polyester

Morphometric study of the testis and reproductive tract （including sperm granuloma） after vasectomy in mature rats

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Asian Journal of Andrology 2016年第1期18卷 66-73页

作者： Li Ma Yang Guo yong yuan Yu-Gen Li Xian-zhong Deng Zheng-Wei Yang Morphometric Research Laboratory North Sichuan Medical College Nanchong 637000 Sichuan China Department of Urological Surgery The Affiliated Hospital of North Sichuan Medical College Nanchong 637000 Sichuan China

By utilizing the rabbit model, previous studies have found good evidence indicating that vasectomy-induced spermatogenic damage is pressure-mediated： the damage occurs when the occluded reproductive tract is unable to accommodate additional spermatozoa produced by the testis. More studies with the more commonly used rat model have shown, however, controversial results on whether and why the damage occurs. In this study, 12 mature male Sprague-Dawley rats were subjected to unilateral vasectomy： double ligation （without severing） of the vas deferens exposed via a small inguinal incision; 37 days after the operation, the testes, epididymides, vasa deferentia （juxta-epididymal segments）, and sperm granulomas （at the vasectomy site） were removed to obtain methacrylate resin-embedded sections and morphometric studies carried out with light microscopy. Marked spermatogenic damage with spermatids and spermatocytes depleted in the seminiferous epithelium in 43% of the seminiferous tubule profiles was demonstrated in 5 of the 12 testes on the vasectomized side, and the damage was associated with smaller or absent sperm granulomas; in the other 7 testes with essentially normal spermatogenesis, there was an increase （by 111% on average） in the volume of the tubule lumen, associated with larger granulomas or granulomas containing more spermatozoa. There was an overall increase （by 66%） in the thickness of the rete testis in the 12 testes; the epididymis or vas deferens showed no distension. It seems therefore that the spermatogenic damage induced by vasectomy in rats is pressure-mediated as well, and that variation in the damage depends mainly on the postoperative development of the sperm granuloma.

关键词： morphometry rat sperm granuloma spermatogenesis vasectomy

A ladder conjugated polymer transducer for solid-contact Cu^(2+)-selective electrodes

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Chinese Chemical Letters 2014年第2期25卷 364-366页

作者： Shun-Yang Yu Yan-Cang Li Tao Xiong Qun yuan yong-Ming Liu zhong-Yi yuan Yi Xiao Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research(YIC)Chinese Academy of Sciences(CAS)Shandong Provincial Key Laboratory of Coastal Environmental ProcessesYICCAS Chemistry and Chemical Engineering College.Yantai University Physical Science and Technical College Dalian University State Key Laboratory of Fine Chemicals Dalian University of Technology

In recent years, there has been a pronounced interest in solid-contact ion-selective electrodes （SC-ISEs）, with emphasis on the use of conducting polymers as ion-to-electron transducer. In this work, a ladder conjugated polymer, thieno[3,2-b]thiophene （LCPT）, was investigated in fabricating Cu2＋-selective electrodes for the first time. The resulting electrodes were characterized by electrochemical impedance spectroscopy （EIS）, chronopotentiometry, and the water layer test. Results proved that the active LCPT facilitates the ion-to-electron transduction, and avoids the detrimental aqueous layer formed at the interface of SC-ISEs.

关键词： Ladder polymer Solid contact Ion-selective electrode Copper

Joint method for reconstructing three-dimensional temperature of flame using Lucy-Richardson and nearest neighbor filtering using light-field imaging

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Science China(Technological Sciences) 2019年第7期62卷 1232-1243页

作者： LI TianJiao yuan yuan SHUAI yong TAN HePing Key Laboratory of Aerospace Thermophysics Ministry of Industry and Information Technology Harbin Institute of Technology

The real-time measurement and reconstruction of three-dimensional temperature are essential when studying the combustion process inside a flame. In the proposed sectioned flame light field imaging model, flame sections are reconstructed based on the characteristics identified using the Lucy-Richardson or nearest neighbor filtering methods, or a joint method involving a combination of both, to improve on the accuracy of two-dimensional temperature reconstruction. Compared to the results of a previous work, the proposed method increases the resolution in the depth of field direction and the extraction of the flame temperature of all sections from the same height ensures the accuracy of the reconstructed temperature distribution across the cross-section of the flame. The relative error when compared to the actual flame is less than 10%. Thus, this approach allows the accurate estimation of the three-dimensional temperature distribution inside a flame, and enables the rapid and effective reconstruction of the three-dimensional temperature field.

关键词： radiative transfer flame light field imaging temperature estimation

Density functional theory calculations of lithium alloying with Ge_(10)H_(16) atomic cluster

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Chinese Chemical Letters 2016年第3期27卷 437-440页

作者： Hang Li Xiao-Qing zhong yong-Lie Sun Cheng-yuan Huang Qi-Hui Wu Department of Chemistry College of Chemistry and Life ScienceQuanzhou Normal University

We exploited a hydrogen-passivated germanium atomic cluster（Ge10H16） as a model to study the mechanism of lithium alloying with germanium. Based on the density functional theory, the electronic and crystal structures of lithium-alloyed Ge10H16 were investigated. The theoretical results indicate that the alloying of lithium with Ge10H16 will weaken the germanium-hydrogen bond and repel the closest germanium atom away from the alloyed lithium atom. Based on the maps of the electron density distribution, the nature of the lithium-germanium chemical bond was analyzed. Moreover, the diffusion process of the lithium on the Ge10H16 cluster was detected, which suggested that there is a close relationship between the diffusion barriers and the coordination number around the lithium atom.

关键词： First-principle calculations Ge atomic cluster Li alloying Electronic structure

Mode-based equivalent multi-degree-of-freedom system for one-dimensional viscoelastic response analysis of layered soil deposit

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Earthquake Engineering and Engineering Vibration 2018年第1期17卷 103-124页

作者： Li Chong yuan Juyun Yu Haitao yuan yong Department of Geotechnical Engineering Tongji University Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji University State Key Laboratory for Disaster Reduction in Civil Engineering Tongji University

Discrete models such as the lumped parameter model and the finite element model are widely used in the solution of soil amplification of earthquakes. However, neither of the models will accurately estimate the natural frequencies of soil deposit, nor simulate a damping of frequency independence. This research develops a new discrete model for onedimensional viscoelastic response analysis of layered soil deposit based on the mode equivalence method. The new discrete model is a one-dimensional equivalent multi-degree-of-freedom（MDOF） system characterized by a series of concentrated masses, springs and dashpots with a special configuration. The dynamic response of the equivalent MDOF system is analytically derived and the physical parameters are formulated in terms of modal properties. The equivalent MDOF system is verified through a comparison of amplification functions with the available theoretical solutions. The appropriate number of degrees of freedom（DOFs） in the equivalent MDOF system is estimated. A comparative study of the equivalent MDOF system with the existing discrete models is performed. It is shown that the proposed equivalent MDOF system can exactly present the natural frequencies and the hysteretic damping of soil deposits and provide more accurate results with fewer DOFs.

关键词： ground response analysis MDOF system mode equivalence modal properties layered soil viscoelastic amplification

Bionics-Inspired Structure Boosts Drag and Noise Reduction of Rotating Machinery

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Journal of Bionic Engineering 2023年第6期20卷 2797-2813页

作者： Shengnan Tang yong Zhu Shouqi yuan Institute of Advanced Manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang212013China International Shipping Research Institute GongQing Institute of Science and TechnologyJiujiang332020China National Research Center of Pumps Jiangsu UniversityZhenjiang212013JiangsuChina Saurer(Changzhou)Textile Machinery Co. LtdChangzhou213200China Leo Group Co. LtdWenling317500China Wenling Fluid Machinery Technology Institute of Jiangsu University Wenling317525China

As a global concern,environmental protection and energy conservation have attracted significant *** to the large carbon emission of electricity,promoting green and low-carbon transformation of the power industry via the synergistic development of clean energy sources is *** machinery plays a crucial role in pumped storage,hydropower generation,and nuclear power *** by bionics,non-smooth features of creatures in nature have been introduced into the structure design of efficient rotating ***,the concept and classification of bionics are ***,the representative applications of non-smooth surface bionic structures in rotating machineries are systematically and comprehensively reviewed,such as groove structure,pit structure,and other non-smooth ***,conclusions are drawn and future directions are *** effective design of a bionic structure contributes toward noise reduction,drag reduction and efficiency improvement of rotating *** and ecological rotating machinery will remarkably reduce energy consumption and contribute to the realization of the“double carbon”goal.

关键词： Bionics Rotating machinery Non-smooth surface Pit structure Groove structure

Fractional Order Iteration for Gradient Descent Method Based on Event-Triggered Mechanism

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Journal of Systems Science & Complexity 2023年第5期36卷 1927-1948页

作者： LU Jiajie WANG yong FAN yuan Department of Automation University of Science and Technology of ChinaHefei 230026China Anhui Engineering Laboratory of Human-Robot Integration System and Intelligent Equipment School of Electrical Engineering and AutomationAnhui UniversityHefei 230601China

In this work,a novel gradient descent method based on event-triggered strategy has been proposed,which involves integer and fractional order ***,the convergence of integer order iterative optimization method and the stability of its associated system with integrator dynamics are *** on this result,a fractional order iteration approach has been developed by modelling the system with fractional order ***,to reduce the comsumption of computation,a feedback based event-triggered mechanism has been introduced to the gradient descent *** convergence of this new event-triggered optimization algorithm is guaranteed by using a Lyapunov method,and Zeno behavior is proved to be avoided ***,the effectiveness and advantages of the proposed algorithms are verified by numerical simulations.

关键词： Event-triggered mechanism fractional order iteration gradient descent Zeno behavior