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基于微分求积法的两端固结刚性吊杆拉力识别研究

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振动与冲击 2025年第2期44卷 94-103页

作者：彭涛稂其林陆小龙王涛田仲初长沙理工大学桥梁工程安全控制教育部重点实验室长沙410114 长沙理工大学土木工程学院长沙410114

以修正Timoshenko梁理论为基础,提出了一种基于微分求积法的拱桥刚性吊杆拉力识别方法。基于修正Timoshenko梁理论建立刚性吊杆横向振动微分方程,通过选取切比雪夫多项式的根作为节点坐标,利用拉格朗日插值基函数近似表示位移函数;根据... 详细信息

以修正Timoshenko梁理论为基础,提出了一种基于微分求积法的拱桥刚性吊杆拉力识别方法。基于修正Timoshenko梁理论建立刚性吊杆横向振动微分方程,通过选取切比雪夫多项式的根作为节点坐标,利用拉格朗日插值基函数近似表示位移函数;根据微分求积法基本原理计算各阶权重系数,引入边界条件后,将轴向力作用下的修正Timoshenko梁横向振动微分方程的求解转化为线性代数方程组广义代数特征值的计算问题,从而得到刚性吊杆实测基频与拉力之间的精确对应关系。通过数值算例和实桥应用对该方法进行了验证,结果表明,当两端固结刚性吊杆的长细比小于222.23时,需要考虑抗弯刚度、剪切变形和转动惯量的影响才能保证拉力识别的精度。提出的基于微分求积法的吊杆拉力识别方法能够应用于各种工况和长细比下的刚性吊杆拉力识别,具有准确、实用和易编程的特点,能够满足实际工程应用要求。

关键词：刚性吊杆修正Timoshenko梁频率法微分求积法拉力识别

具有n^(+)埋层和L型场板的Si/SiC异质结沟槽LDMOS器件

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半导体技术 2025年第2期50卷 134-140页

作者：康怡刘东卢山鲁啸龙胡夏融西南交通大学电气工程学院成都611756 西南交通大学集成电路科学与工程学院成都611756 西华大学理学院成都610039

Si/4H-SiC异质结构能够同时结合Si材料的成熟工艺和SiC材料的宽禁带特性,在功率器件设计中具有巨大潜力。提出了一种具有n+埋层和L型场板的Si/SiC异质结沟槽横向双扩散金属氧化物半导体(LDMOS)器件。位于Si/SiC异质结界面SiC侧的重掺杂n... 详细信息

Si/4H-SiC异质结构能够同时结合Si材料的成熟工艺和SiC材料的宽禁带特性,在功率器件设计中具有巨大潜力。提出了一种具有n+埋层和L型场板的Si/SiC异质结沟槽横向双扩散金属氧化物半导体(LDMOS)器件。位于Si/SiC异质结界面SiC侧的重掺杂n+埋层能够有效降低界面势垒宽度,增强电子隧穿效应,降低界面电阻,进一步降低比导通电阻。位于厚氧化层角落并与漏极相连的L型场板通过在SiC漂移区和厚氧化层之间产生高电场,重塑器件横向和纵向电场强度分布,将击穿点从表面转移至体内,提高击穿电压。仿真结果表明,与传统SiC LDMOS器件相比,该器件的品质因数从109.29 MW/cm^(2)提升至159.92 MW/cm^(2),提高了46.36%,进一步改善了LDMOS器件导通电阻和击穿电压之间的折中关系,器件性能得到优化。

关键词：横向双扩散金属氧化物半导体(LDMOS) Si/4H-SiC异质结 n^(+)埋层 L型场板功率品质因数

Principle and Experimental Verification of Novel Dual Driving Face Rotary Ultrasonic Motor

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Chinese Journal of Mechanical Engineering 2013年第5期26卷 1006-1012页

作者： lu xiaolong HU Junhui YANG Lin ZHAO Chunsheng State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

Existing rotary ultrasonic motors operating in extreme environments cannot meet the requirements of good environmental adaptability and compact structure at same time,and existing ultrasonic motors with Langevin transducers show better environmental adaptability,but size of these motors are usually big due to the radial arrangement of the Langevin transducers.A novel dual driving face rotary ultrasonic motor is proposed,and its working principle is experimentally *** working principle of the novel ultrasonic motor is firstly *** 5th in-plane flexural vibration travelling wave,excited by the Langevin transducers around the stator ring,is used to drive the *** the finite element method is used in the determination of dimensions of the prototype motor,and the confirmation of its working *** that,a laser Doppler vibrometer system is used for measuring the resonance frequency and vibration amplitude of the *** last,output characteristics of the prototype motor are measured,environmental adaptability is tested and performance for driving a metal ball is also *** room temperature and 200 V(zero to peak) driving voltage,the motor’s no-load speed is 80 r/min,the stalling torque is 0.35 N·m and the maximum output power is 0.85 *** response time of this motor is 0.96 ms at the room temperature,and it decreases or increases little in cold environment.A metal ball driven by the motor can rotate at 210 r/min with the driving voltage 300 V(zero to peak).Results indicate that the prototype motor has a large output torque and good environmental adaptability.A rotary ultrasonic motor owning compact structure and good environmental adaptability is proposed,and lays the foundations of ultrasonic motors’ applications in extreme environments.

关键词： ultrasonic motor piezoelectric transducer dual driving face in-plane flexural vibration mode

A novel in-plane mode rotary ultrasonic motor

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Chinese Journal of Aeronautics 2014年第2期27卷 420-424页

作者： lu xiaolong Hu Junhui Yang Lin Zhao Chunsheng State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics & Astronautics

Ultrasonic motors have the merits of high ratio of torque to volume, high positioning precision, intrinsic holding torque, etc., compared to the conventional electromagnetic motors. There have been several potential applications for this type of motor in aerospace exploration, but bearings and bonding mechanism of the piezoelectric ring in the motors limit the performance of them in the space operation conditions. It is known that the Langevin type transducer has excel- lent energy efficiency and reliability. Hence using the Langevin type transducer in ultrasonic motors may improve the reliability of piezoelectric motors for space applications. In this study, a novel in-plane mode rotary ultrasonic motor is designed, fabricated, and characterized. The proposed motor operates in in-plane vibration mode which is excited by four Langevin-type bending vibra- tors separately placed around a ring-shaped stator. Two tapered rotors are assembled to the inner ring of the stator and clamped together by a screw nut. In order to make the motor more stable and convenient to fix, a thin cylindrical support is placed under the stator ring. Due to its no-bearing structure and Langevin transducer excitation, the prototype ultrasonic motor may operate well in aeronautic and astronautic environments.

关键词： In-plane vibration Langevin transducers No-bearing Rotary driving Ultrasonic devices

Exploring a balance between strength and ductility of hexagonal BN nanoplatelet reinforced ZK61 magnesium composite

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Journal of Magnesium and Alloys 2024年第5期12卷 1899-1910页

作者： Kewei Zhang xiaolong lu Yufeng Sun Shaokang Guan Yao Chen School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Advanced Magnesium Alloys in Henan Province Zhengzhou UniversityZhengzhou 450002China Key Laboratory of Advanced Materials Processing&Mold Ministry of EducationZhengzhou 450002China School of Mechanical and Electrical Engineering Soochow UniversitySuzhou 215021China

The practical applications of magnesium(Mg)alloys are usually beset by their relatively low strength and limited *** we attempt to fabricate hexagonal BN nanoplatelet(BNNP)reinforced ZK61 magnesium composites using a combination of spark plasma sintering and friction stir *** resulting composites exhibit microstructural characteristics of homogeneous dispersion of BNNP in Mg matrix with refined equiaxed grains and(0002)basal texture roughly surrounding the pin column *** electron microscopy observation illustrates that trace amounts of Mg_(3)N_(2)and MgB_(2)form at BNNP-Mg interface,in which Mg_(3)N_(2)locates at the basal plane of a BNNP and MgB_(2)grows at its open *** spatial distribution of Mg_(3)N_(2)and MgB_(2)facilitates interfacial wetting and stronger BNNP-Mg interface in such a way that interfacial products act as anchors bonding between *** comparison with monolithic ZK61 alloy,the BNNP/ZK61 composites display simultaneous improvements in yield strength,hardness and ductility,achieving good strength-ductility *** research is expected to shed some light on BNNP potentials for designing and producing magnesium composites with high strength and good ductility.

关键词： BN nanoplatelet Magnesium composite Strength Ductility Spark plasma sintering Friction stir processing

Simulation of ChIP-Seq based on extra-sonication of IPed DNA fragments

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Chinese Science Bulletin 2010年第22期55卷 2380-2389页

作者： WANG Wei SHI xiaolong lu ZuHong State Key Laboratory of Bioelectronics School of Biological Science and Medical Engineering Southeast University Nanjing 210096 China

The combination of chromatin immunoprecipitation with sequencing (ChIP-Seq) is an effective method for obtaining an in vivo genome-wide profile of the interaction of a protein with DNA. With the dramatic development of high-throughput short sequencing technologies, several new algorithms have been developed to process ChIP-Seq. However, the reported analytical tools for ChIP-Seq based on size selection of immunoprecipitated (IPed) DNA fragments are mainly adopted on the Solexa system. As a sequencer with the highest throughput, few studies of ChIP-Seq based on SOLiD system have been reported. The main difference of the SOLiD and Solexa systems exists in the length of DNA fragments during preparing sequencing libraries. The SOLiD system has relatively short DNA fragments if it processes a further sonication of IPed DNA fragments in order to meet the length requirement of DNA fragments for emulsion-PCR (ePCR). This work aims to investigate the influences of DNA fragment length on data analysis from ChIP-Seq. Previous studies show that typical bimodal peaks can be observed in Solexa ChIP-Seq data, but based on the analysis of the real SOLiD ChIP-Seq data in this study, we found that there were no double peaks with apparent reads shift in a local enriched region and the local reads distribution of peaks were tested by normal distribution. Using real and simulated ChIP-Seq data, three main ChIP-Seq algorithms (CisGenome, SISSRs and MACS) have been investigated. We found that algorithms developed for processing ChIP-Seq data generated from Solexa library protocol, cannot efficiently capture the feature of the ChIP-Seq data from SOLiD library. Misuse of those analytical tools would be a possible reason for failure of ChIP-Seq on the SOLiD system. Therefore, a new ChIP-Seq analytical strategy for an extra-sonication of IPed DNA fragments needs to be developed.

关键词： DNA片段超声模拟染色质免疫沉淀 iD系统芯片片段长度聚合酶链反应

Evaluation of the relative γ-ray intensities emitted from ^(56)Co and ^(66)Ga

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Nuclear Science and Techniques 2009年第6期20卷 363-368页

作者： YU Weixiang HUANG xiaolong CHEN Xiongjun lu Hanlin China Institute of Atomic Energy Beijing 102413 China

56Co and 66Ga with γ-ray energies covering the range of 0.84-3.55 and 0.68-4.81MeV, respectively, are important radionuclides for Ge detector calibration. The newly evaluated relative γ-ray intensities were recommended using the measurements finished after 2000 year by Baglin and Browne in 2004. In 2005 China groups measured the relative γ-ray intensities. The China measurements were about 2% systematically lower than other measurements and these evaluations. In this paper the discrepancies among these measurements and the evaluations are analyzed carefully and the new evaluations are re-recommended.

关键词： γ射线强度评价相对测量排放放射性核素推荐使用测量系统探测器

Electron-induced damage to NPN transistors under different fluxes

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Nuclear Science and Techniques 2008年第6期19卷 333-336页

作者： ZHENG Yuzhan lu Wu REN Diyuan GUO Qi YU Xuefeng lu xiaolong Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of Sciences Urumqi 830011 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

Radiation damage of NPN transistors under different fluxes with electron energy of 1.5 MeV was investigated in this article. It has been shown that when NPN transistors were irradiated to a given fluence at different electron fluxes, the shift of base current was dependent on flux. With electron flux decreasing, the shift of base current becomes larger, while collector current almost keeps constant. Thus, more degradation of NPN transistors could be caused by low-electron-flux irradiation, similar to enhanced low-dose-rate sensitivity (ELDRS) of transistors under 60Co γ-irradiation. Finally, the underlying mechanisms were discussed here.

关键词：电子通量 NPN晶体管辐射损伤核技术

Tailoring the microstructure,mechanical and tribocorrosion performance of (CrNbTiAlV)N_(x) high-entropy nitride films by controlling nitrogen flow

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Journal of Materials Science & Technology 2022年第12期107卷 172-182页

作者： Cunxiu Zhang xiaolong lu Cong Wang Xudong Sui Yanfang Wang Haibin Zhou Junying Hao State Key Laboratory of Solid lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Qingdao Center of Resource Chemistry and New Materials Qingdao 266000China

The(CrNbTiAlV)N_(x)high-entropy nitride films were fabricated by adjusting nitrogen flow via magnetron *** microstructure,mechanical,electrochemical and tribocorrosion performances of the films were *** results show that the films transform from amorphous to nanocrystalline structure as nitrogen flow *** nanocrystalline films show super hardness(>40 GPa)and adhesion strength(>50 N).The amorphous film has a pretty anti-corrosion in static corrosion,while not in tribocorrosion *** film deposited at nitrogen flow of 38 sccm exhibits the optimal tribocorrosion performance in artificial seawater,with the highest open circuit potential(∼−0.1 V ***/AgCl),the lowest friction coefficient(∼0.162)and wear rate(∼7.48×10^(−7)mm^(3)N^(−1)m^(−1)).

关键词： High-entropy nitride films Nitrogen flow Tribocorrosion performance Magnetron sputtering