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Polarization properties of porous anodic alumina with Y-branched Cu nanowires

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Chinese Optics Letters 2008年第4期6卷 297-299页

作者：苏学军张立春李清山梁德春 Naval aeronautical and Astronautical University Yantai 264001 Naval aeronautical and Astronautical University Yantai 264001 3 college of Physics and Engineering Qufu Normal UniversityQufu 273165 college of Physics Ludong University Yantai 264025 college of Physics and Engineering Qufu Normal University Qufu 273165

Porous anodic alumina （PAA） templates with branch structure are fabricated by the two-step anodic oxidation processes, and then the Y-branched Cu nanowires are synthesized in the templates using an alternating current （AC） deposition method. We observe the morphology image of the samples by scanning electron microscopy （SEM）, and measure the transmission spectrum and the polarization spectrum of the samples by the spectrophotometer. The results show that PAA films with Y-branched Cu nanowires have better transmittance in the near infrared region. An extinction ratio of 15 - 18 dB and an insertion loss of 0.1 - 0.4 dB are obtained in this region. Therefore PAA with Y-branched Cu nanowires can be used as a near-infrared micropolarizer, and this kind of micropolarizer would have a promising future in the field of photoelectricity integration.

关键词： Cu Polarization properties of porous anodic alumina with Y-branched Cu nanowires

White Light Emission from ZnS:Mn Thin Films Deposited on GaN Substrates by Pulsed Laser Deposition

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Chinese Physics Letters 2016年第7期33卷 129-132页

作者：王彩凤李清山王继锁赵风周张立春 college of Physics and Engineering Qufu Normal University college of aeronautical Engineering Binzhou University School of Physics and Optoelectronic Engineering Ludong University

ZnS：Mn thin films are grown on CaN substrates by pulsed laser deposition. The structure, morphology and optical properties are investigated by x-ray diffraction, scanning electron microscopy and photolumineseenee （PL）. The obtained ZnS：Mn thin films are grown in preferred orientation along β-ZnS （111） direction corresponding to crystalline structure of cubic phase. The deposition temperature has an obvious effect on the structure, surface morphology and optical properties of ZnS：Mn thin films. PL measurements show that there are two emission bands located at 44Ohm and 595 nm when the films are deposited at temperatures from 100℃ to 500℃. The relative integrated intensity of the blue emission and orange-red emission is determined by the deposition conditions. At the proper deposition temperature of 300℃, the color coordinate is closest to （0.33, 0.33）. The ZnS：Mn films on CaN substrates can exhibit white light emission.

关键词： ZnS in rate GaN Mn by from

Modeling vibration behavior of delaminated composite laminates using meshfree method in Hamilton system

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Applied Mathematics and Mechanics(English Edition) 2015年第5期36卷 633-654页

作者： Jie CHEN Hai WANG Guanghui QING School of Aeronautics and Astronautics Shanghai Jiao Tong University college of aeronautical Engineering Civil Aviation University of China

Free vibration analysis of composite laminates with delaminations is performed based on a three-dimensional semi-analytical model established by introducing the local radial point interpolation method（LRPIM） into a Hamilton system. The governing equation is derived with a transfer matrix technique and a spring layer model based on a local weak-form equivalent to the modified Hellinger-Reissner variational principle. Main superiority of the present model is that the scale of the governing equation involves only the so-called state variables at the top and bottom surfaces, and is insensitive to the thickness and the layer number of the composite laminates. Several numerical examples for analyzing the vibration frequencies and mode shapes of delaminated composite beams and plates are given to validate the model. The results are in good agreement with the pre-existing results.

关键词： interpolation superiority validate variational laminated overlapping quadrature radial insensitive symmetric

Characteristic of rich-mixture ignition kernel driven by nanosecond repetitive pulsed discharge

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Science China(Technological Sciences) 2016年第1期59卷 109-116页

作者： LIN BingXuan WU Yun LI YiWen JIA Min ZONG HaoHua DING Jian LI YingHong college of aeronautical and Astronautical Engineering Air Force Engineering University School of Electrical Engineering Xi'an Jiaotong University

Plasma-assisted ignition is a promising technology to improve engine performance. Nanosecond repetitive pulsed discharge is widely used in plasma-assisted ignition owing to its chemical activations and thermal and hydrodynamic expansions. However, the influence of ultrafast heating and hydrodynamic effects on the development of the rich-mixture ignition kernel is largely unknown. The present study aims to illustrate these effects using electrical and schlieren measurement. The number and the frequency of discharge pulses are exactly controlled to establish the relationship among the discharge energy, frequency, and rich-mixture ignition-kernel characteristics. The evolution of the ignition kernel in the early stage is mainly dominated by the discharge energy and frequency, i.e., a greater energy and a higher frequency yield a larger ignition kernel. Moreover, the influence of both the energy and frequency on the ignition kernel gradually disappears as the ignition kernel develops. According to the experimental data and theoretical analysis, the calculated laminar burning velocity is 0.319 m/s with a Markstein length of 13.43±0.11 cm when the voltage is 5.9 k V, the frequency is 3 k Hz, and the equivalence ratio is 1.3. This result indicates that the rich-mixture flame is stable in the early stage of ignition.

关键词： plasma-assisted ignition NRP discharge rich-mixture ignition kernel laminar burning velocity markstein length

Study on behaviors of functionally graded shape memory alloy cylinder

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Acta Mechanica Solida Sinica 2017年第6期30卷 608-617页

作者： Bingfei Liu Qingfei Wang Rui Zhou Chunzhi Du Yanan Zhang Pan Zhang Airport college Civil Aviation University of China Tianjin 300300 China aeronautical engineering college Civil Aviation University of China Tianjin 300300 China

For better controllability in actuations,it is desirable to create Functionally Graded Shape Memory Alloys（FG-SMAs）in the actuation *** can be achieved by applying different heat treatment processes to create the gradient along the radius of a SMA *** solutions are derived to predict the macroscopic behaviors of such a functionally graded SMA *** Tresca yield criterion and linear hardening are used to describe the different phase transformations with different gradient *** numerical results for an example of the model exhibit different pseudo-elastic behaviors from the non-gradient case,as well as a variational hysteresis loop for the transformation,providing a mechanism for easy actuation *** the gradient disappears,the model can degenerate to the non-gradient case.

关键词： Shape memory alloy Gradient Constitutive model Cylinder Internal pressure

A new method of single celestial-body sun positioning based on theory of mechanisms

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Chinese Journal of Aeronautics 2016年第1期29卷 248-256页

作者： Zhang Wei Xu Xiaofeng Wu Yuanzhe Airport college Civil Aviation University of China Tianjin 300300China Aviation Ground Special Equipment Research Base Tianjin 300300China aeronautical Automation college Civil Aviation University of ChinaTianjin 300300China aeronautical Engineering college Civil Aviation University of ChinaTianjin 300300China

Considering defects of current single celestial-body positioning methods such as discon- tinuity and long period, a new sun positioning algorithm is herein put forward. Instead of tradi- tional astronomical spherical trigonometry and celestial coordinate system, the proposed new positioning algorithm is built by theory of mechanisms. Based on previously derived solar vector equations （from a C1R2p2 series mechanism）, a further global positioning method is developed by inverse kinematics. The longitude and latitude coordinates expressed by Greenwich mean time （GMT） and solar vector in local coordinate system are formulated. Meanwhile, elimination method of multiple solutions, errors of longitude and latitude calculation are given. In addition, this algo- rithm has been integrated successfully into a mobile phone application to visualize sun positioning process. Results of theoretical verification and smart phone＇s test demonstrate the validity of pre- sented coordinate＇s expressions. Precision is shown as equivalent to current works and is acceptable to civil aviation requirement. This new method solves long-period problem in sun sight running fix- ing and improves applicability of sun positioning. Its methodology can inspire development of new sun positioning device. It would be more applicable to be combined with inertial navigation systems for overcoming discontinuity of celestial navigation systems and accumulative errors of inertial nav- igation systems.

关键词： Celestial navigation Inverse kinematics Longitude and latitude coordinates Mechanisms Navigation systems Position measurement Single celestial-body posi-tioning Sun

Design and Testing of a Novel Piezoelectric-Driven Microvibration Hammerhead

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Nanomanufacturing and Metrology 2023年第1期6卷 79-87页

作者： Zhiyong Guo Zhemin Shen Weidong Liu Zhiqiang Zhang Lifeng Zhang Xuhao Wang college of aeronautical Engineering Civil Aviation University of ChinaTianjin 300300China

A novel microvibration hammerhead consists of a piezoelectric actuator and a double cross-shape compliant mechanism(DCCM)is presented in this *** output force of the piezoelectric actuator can be detected in real time by an insideinstalled pressure sensor.A theoretical model including the stiffness,first natural frequency,and stress of the DCCM and the displacement output of the piezoelectric actuator are established,and then they are further analyzed using the finite element analysis *** effects of the beam thickness on the static and dynamic properties are deeply analyzed and compared.A prototype micro hammering system is constructed by integrating the microvibration hammerhead assembly and controlling *** experiments are also carried out to verify the basic performance of the micro hammering system.

关键词： Piezoelectric Flexure hinge Micro hammering

Low thermal expansion and broad band photoluminescence of Zr0.1Al1.9Mo2.9V0.1O12

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Chinese Physics B 2021年第3期30卷 423-429页

作者： Jun-Ping Wang Qing-Dong Chen Li-Gang Chen Yan-Jun Ji You-Wen Liu Er-Jun Liang Shandong Engineering Research Center of aeronautical Materials and Devices Key Laboratory of Aeronautical Optoelectronic Materials and DevicesCollege of Aeronautical EngineeringBinzhou UniversityBinzhou 256603China college of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Physical Science&Engineering and Key Laboratory of Materials Physics of Ministry of Education Zhengzhou UniversityZhengzhou 450052China

A new material of Zr0.1Al1.9Mo2.9V0.1O12 is synthesized by the traditional solid state synthesis *** phase transition,coefficient of thermal expansion,and luminescence properties of Zr0.1Al1.9Mo2.9V0.1O12 are explored with Raman spectrometer,dilatometer,and x-ray diffraction(XRD)*** results show that the Zr0.1Al1.9Mo2.9V0.1O12 possesses the strong broad-band luminescence characteristics almost in the whole visible *** sample is crystallized in a monoclinic structure group of P21/a(No.14)crystallized at room temperature(RT).The crystal is changed from monoclinic to orthorhombic structure when the temperature increases to 463 *** material has very low thermal expansion performance in a wide temperature *** excellent low thermal expansion and strong pale green light properties in a wide temperature range suggest its potential applications in light-emitting diode(LED)and other optoelectronic devices.

关键词： low thermal expansion phase transition x-ray diffraction(XRD) Raman spectrum luminescence

Airframe Damage Region Division Method Based on Structure Tensor Dynamic Operator

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Journal of Shanghai Jiaotong university(Science) 2022年第6期27卷 757-767页

作者： CAI SHUYU SHI LIZHONG college of aeronautical Engineering Civil Aviation University of ChinaTianjin 300300China

In order to improve the accuracy of damage region division and eliminate the interference of damage adjacent region,the airframe damage region division method based on the structure tensor dynamic operator is proposed in this *** structure tensor feature space is established to represent the local features of damage *** makes different damage images have the same feature distribution,and transform varied damage region division into consistent process of feature space *** this basis,the structure tensor dynamic operator generation method is *** integrates with bacteria foraging optimization algorithm improved by defining double fitness function and chemotaxis rules,in order to calculate the parameters of dynamic operator generation method and realize the structure tensor feature space *** then the airframe damage region division is *** experimental results on different airframe structure damage images show that compared with traditional threshold division method,the proposed method can improve the division *** interference of damage adjacent region is *** information loss caused by over-segmentation is *** it is efficient in operation,and consistent in *** also has the applicability to different types of structural damage.

关键词： airframe damage region division dynamic operator structure tensor feature distribution double fitness function intelligent maintenance