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扭曲双层石墨烯的层间电导特性研究

原子与分子物理学报 2025年第6期42卷 83-88页

作者：陶懿洲刘超方贺男南京邮电大学电子与光学工程学院南京210023

扭曲双层石墨烯(TBG)由于具有莫特绝缘和非常规超导等新奇的电学特性,在纳米技术领域存在巨大的应用潜力.本文基于光学衍射物理方法,构建了一个适用于TBG的理论模型,并利用该理论模型研究了TBG的层间电导特性.研究结果较好地解释了TBG... 详细信息

扭曲双层石墨烯(TBG)由于具有莫特绝缘和非常规超导等新奇的电学特性,在纳米技术领域存在巨大的应用潜力.本文基于光学衍射物理方法,构建了一个适用于TBG的理论模型,并利用该理论模型研究了TBG的层间电导特性.研究结果较好地解释了TBG层间电导随扭转角变化的实验结果,并阐明了其物理机制.此外,本文还计算了电极参数、隧穿层厚度以及界面势强度等物理因素对层间电导特性的影响.计算结果表明:随着电极化学势的增大,层间电导关于扭转角的变化曲线近似整体向上平移;层间电导随着上层隧穿层厚度的增加而衰减并趋于稳定,而随着下层隧穿层厚度振荡;TBG两层扭转石墨烯的界面势强度越强,则层间电导随扭转角下降得越快.

关键词：低维物理层间电导光学衍射方法扭曲双层石墨烯

Nonlinear effect induced in thermally poled glass waveguides

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第1期7卷 105-108页

作者： REN yi-tao COM Technical University of Denmark DK-2800 Kgs.Lyngby Denmark

Thermally poled germanium-doped channel waveguides are presented. Multilayer waveguides containing a silicon oxynitride layer were used as charge trapper in this investigation on the effect of the internal field inside the waveguide. Compared to waveguides without the trapping layer, experimental results showed that the induced linear electro-optic (EO) coefficient increases about 20% after poling, suggesting strongly that the internal field is relatively enhanced, and showed it is a promising means for improving nonlinearity by poling in waveguides.

关键词： Electro-optic (EO) effect Waveguides Glass Poling

Singularity radius gradient-based rapid singularity-escape steering law for SGCMGs

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Chinese Journal of Aeronautics 2020年第10期33卷 2728-2742页

作者： tao yi Yunhai GENG Baolin WU Research Center of Satellite Technology Harbin Institute of TechnologyHarbin 150080China

In order to visualize singularity of SGCMGs in gimbal angle space,a novel continuous bounded singularity parameter--Singularity Radius,whose sign can distinctly determine singularity type,is *** a rapid singularity-escape steering law is proposed basing on gradient of Singularity Radius and residual base vector to drive the SGCMG system to neighboring singular boundary,and quickly escape elliptic ***,simulation results on Pyramid-type and skew-type configuration demonstrate the effectiveness and rapidness of the proposed steering law.

关键词： Gaussian curvature Rapid singularity escape Single gimbal control moment gyroscope Singularity-escape steering law Singularity parameter Singularity type

Friction and wear behavior and mechanism of low carbon microalloyed steel containing Nb

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China Foundry 2023年第3期20卷 263-270页

作者： Mei-yi Yuan Jia-cheng Zhang yi-tao Yang School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

Dry sliding friction and wear test of Nb containing low carbon microalloyed steel was carried out at room temperature,and the effect of Nb on the wear behavior of the steel,as welll as the mechanism was *** electron microscopy(SEM) and energy dispersive spectrometry(EDS) were employed to analyze the morphology and composition of the worn surface,and the structure evolution of the plastic deformation *** carbide content and type in the steel were analyzed by the electrolytic extraction device and X-ray diffraction(XRD).The experimental results demonstrate that the addition of 0.2% Nb can refine the grain and generate Nb C to improve the wear resistance of the *** enhancing the load and speed of wear experiment,the wear mechanism of the test steel with 0.2% Nb changes from slight oxidation wear to severe adhesion wear and oxidation *** with the load,the increase in the rotation speed exerts a greater influence on the wear of the test steel.

关键词： Nb content low carbon microalloyed steel friction and wear carbide

Nanopore sensing system for high-throughput single molecular analysis

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Science China Chemistry 2018年第12期61卷 1483-1485页

作者： Zhen Gu yi-Lun ying yi-tao Long Key Laboratory for Advanced Materials & School of Chemistry and Molecular EngineeringEast China University of Science and Technology Shanghai 200237China

Nanopore technique enables a sensitive, label free, low cost and high throughput method for single-molecule analysis[1–4]. Usually, the nanopore is fabricated on an insulating membrane with electrolyte solution in two sides, which can act as the only pathway for the ionic flow. When a single molecule enters the pore under the applied biased potential, it will temporarily block the ionic current flow through the nanopore. By analyzing the amplitude, duration, shape and frequency spectra of ionic current modulations, nanopore detection could provide the characteristics of the analytes.

关键词： Nanopore sensing system high-throughput single molecular analysis

Effect of heat treatment on microstructure and mechanical properties of Ti-containing low alloy martensitic wear-resistant steel

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China Foundry 2023年第4期20卷 329-338页

作者： Kai Lan Wang Ding yi-tao Yang School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

Effects of quenching temperature and cooling conditions(water cooling and 10%NaCl cooling)on microstructure and mechanical properties of a 0.2%Ti low alloy martensitic wear-resistant steel used for die casting ejector plate were *** results show that lath martensite can be obtained after austenitizing in the range of 860-980℃and then water *** an increase in austenitizing temperature,the precipitate content gradually *** precipitates are mainly composed of TiC and Ti4C2S2,and their total content is between 1.15wt.%and 1.64wt.%.The precipitate phase concentration by water-cooling is higher than that by10%NaCl cooling due to the lower cooling rate of water *** the austeniting temperature increases,the hardness and tensile strength of both water cooled and 10%NaCl cooled steels firstly increase and then *** experimental steel exhibits the best comprehensive mechanical properties after being austenitized at 900℃,cooled by 10%NaCl,and then tempered at 200℃.Its hardness,ultimate tensile strength,and wear rate reach551.4 HBW,1,438.2 MPa,and 0.48×10^(-2)mg·m^(-1),respectively.

关键词： low alloy wear-resistant steel quenching temperature cooling condition precipitate retained austenite wear resistance

Influence of Blade Thickness on Transient Flow Characteristics of Centrifugal Slurry Pump with Semi-open Impeller

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Chinese Journal of Mechanical Engineering 2016年第6期29卷 1209-1217页

作者： tao yi YUAN Shouqi LIU Jianrui ZHANG Fan tao Jianping National Research Center of Pumps and Pumping System Engineering and Technology Jiangsu University Zhenjiang 212013 China yixing taoye Nonmetallic Chemical Machinery Factory Co. Ltd. Wuxi 214222 China

As the critical component, the impellers of the slurry pumps usually have blades of a large thickness. The increasing excretion coefficient of the blades affects the flow in the impeller resulting in a relatively higher hydraulic loss, which is rarely reported. In order to investigate the influence of blade thickness on the transient flow characteristics of a centrifugal slurry pump with a semi-open impeller, transient numerical simulations were carried out on six impellers, of which the meridional blade thickness from the leading edge to trailing edge varied from 5-10 mm, 5-15 mm, 5-20 mm, 10-10 mm, 10-15 mm, and 10-20 mm, respectively. Then, two of the six impellers, namely cases 4 and 6, were manufactured and experimentally tested for hydraulic performance to verify the simulation results. Results of these tests agreed reasonably well with those of the numerical simulation. The results demonstrate that when blade thickness increases, pressure fluctuations at the outlet of the impeller become severe. Moreover, the standard deviation of the relative velocity in the middle portion of the suction sides of the blades decreases and that at the outlet of the impeller increases. Thus, the amplitude of the impeller head pulsation for each case increases. Meanwhile, the distribution of the time-averaged relative flow angle becomes less uniform and decreases at the outlet of the impeller. Hence, as the impeUer blade thickness increases, the pump head drops rapidly and the maximum efficiency point is offset to a lower flow rate condition. As the thickness of blade trailing edge increases by 10 mm, the head of the pump drops by approximately 5 m, which is approximately 10 % of the original pump head. Futhermore, it is for the first time that the time-averaged relative flow angle is being considered for the analysis of transient flow in centrifugal pump. The presented work could be a useful guideline in engineering practice when designing a centrifugal slurry pump with thick i

关键词： centrifugal slurry pump blade thickness transient flow characteristics time-averaged relative flow angle semi-openimpeller

Nanopore-based sensing interface for single molecule electrochemistry

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Science China Chemistry 2019年第12期62卷 1576-1587页

作者： Rui Gao Yao Lin yi-Lun ying yi-tao Long Department of Chemistry University of UtahSalt Lake CityUtah 84112USA School of Chemistry&Molecular Engineering East China University of Science and TechnologyShanghai 200237China State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Nanopore techniques are experiencing a gallop since it walked out the notebook and show its charm on the science *** nanoscale pore offers a single-molecule resolution with a label-free and high-selective manner for the research of molecular structures,molecular dynamics,single-molecule reactions and for a variety of applications in biophysics and *** this review,we introduce the construction of three types of nanopore platforms along with the latest progress in DNA sensing,structure and dynamics analysis of peptides/proteins,and the detection of redox reactions with new sensing ***,we depict nanopore data processing methods which provide an insight of data mining under the background ofbig *** could fully expect the great impact of nanopore techniques on not only for DNA sequencing and sensing applications,but also in protein sequencing and clinical diagnostics.

关键词： nanopore single-molecule sensing nanoelectrochemistry

Ultra-low noise measurements of nanopore-based single molecular detection

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Science Bulletin 2017年第18期62卷 1245-1250页

作者： Zhen Gu Huifeng Wang yi-Lun ying yi-tao Long Key Laboratory for Advanced Materials & School of Chemistry and Molecular Engineering East China University of Science and Technology Shanghai 200237 China School of Information Science and Engineering East China University of Science and Technology Shanghai 200237 China

Nanopore is an ultra-sensitive electrochemical technique for single molecular detection in confined space. To suppress the noise in detection of the weak current of nanopore, we investigated the influence of membrane capacitance and applied voltage on the noise of the current signal by model analysis, simulation and experiment. The obtained results demonstrated that membrane capacitance affects the noise by amplifying the noise of the applied voltage. Therefore, suppression of applied voltage noise is an efficient approach for reducing the noise in nanopore detection. Here, we developed an ultra-low noise instrument system for detecting the single molecule signal in nanopores. As demonstrated by nanopore experiments, the p-p noise of the developed system during the recording is reduced to 3.2B pA using the filter of 5 kHz. Therefore, the developed system could be applied in highly sensitive nanopore detection.

关键词： Nanopore Membrane capacitance Current amplifier Signal amplifier and recording High current resolution