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Investigation of electron beam effects on L-shell Mo plasma produced by a compact LC generator using pattern recognition

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Matter and Radiation at Extremes 2019年第2期4卷 52-58页

作者： M.F.yilmaz y.Danisman M.Ozdemir b.Karlık J.Larour basic Sciences Engineering DepartmentImam Abdulrahman Bin Faisal UniversityDammamSaudi Arabia Department of Mathematics and Computer Sciences Queensborough Community CollegeCUNYBaysideNew York 11364USA Neurosurgical Simulation Research and Training Centre Department of NeurosurgeryMontreal Neurological Institute and HospitalMcGill UniversityMontrealQuebec H3A 2B4Canada Laboratoire de Physique des Plasmas(LPP) Ecole PolytechniqueUPMCCNRSPalaiseauFrance

In this paper,the effects of an electron beam on X-pinch-produced spectra of L-shellMoplasma are investigated for the first time by principal component analysis(PCA);this analysis is compared with that of line ratio diagnostics.A spectral database for PCA extraction is arranged using a non-Local Thermodynamic Equilibrium(non-LTE)collisional radiative L-shell Mo *** vector spectra of L-shell Mo,including F,Ne,Na and Mg-like transitions are studied to investigate the polarization types of these ***1 vector spectra of F,Ne,Na and Mg-like transitions result in linear polarization of Stokes Q ***,PC2 vector spectra show linear polarization of Stokes U profiles of 2p^(5)3s of Ne-like transitions which are known as responsive to a magnetic field[Trabert,beiersdorfer,and Crespo Lo´pez-Urrutia,*** ***.,Sect.b 408,107–109(2017)].A 3D representation of PCA coefficients demonstrates that addition of an electron beam to the non-LTE model generates quantized,collective clusters which are translations of each other that follow V-shaped cascade trajectories,except for the case f=*** extracted principal coefficients are used as a database for an Artificial Neural Network(ANN)to estimate the plasma electron temperature,density and beam fractions of the time-integrated,spatially resolved L-shellMoX-pinch plasma ***-based ANNs provide an advantage in reducing the network topology,with a more efficient backpropagation supervised learning *** modeled plasma electron temperature is about Te;660 eV and density n_(e)=1×10^(20) cm^(-3),in the presence of the fraction of the beams with f-0.1 and centered energy of 5 keV.

关键词： spectrum. beam transitions

Influence of optical filtering on transmission capacity in single mode fiber communications

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Frontiers of Optoelectronics 2015年第4期8卷 424-430页

作者： M. Venkata SUDHAKAR y. Mallikarjuna REDDy.b. Prabhakara RAO Department of Electronics and Communication Engineering Jawaharlal Nehru Technological (JNT) University Kakinada AP India Department of Electronics and Communication Engineering Vasireddy Venkatadri Institute of Technology Guntur AP India

This paper presents the design and analysis of optical filters that are placed at the output of directly modulated vertical cavity surface emitting laser （VCSEL） in the process of inexpensive transmitter＇s implementation for upcoming generation optical access network. Generation of non return to zero （NRZ） optical signal from the transmitter for 110 km error-free single mode fiber （SMF） transmission at 10 Gb/s with bit error rate （bER） of 10-30 in the absence of the external modulator and encoder was proposed. Effects of super-Gaussian and butterworth optical filters at VCSEL output were demonstrated to maximize performance of SMF optical systems without need of any dispersion compensation technique.

关键词： single mode fiber (SMF) optical filter,dispersion data rate

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电阻式核磁共振测量的最新进展

物理学报 2012年第14期61卷 366-378页

作者：刘洪武杨凯锋 T.D.Mishima M.b.Santos K.Nagase y.Hirayama 吉林大学超硬材料国家重点实验室原子与分子物理研究所长春130012 ERATO Nuclear Spin Electronics Project-JST SendaiMiyagi 980-8578Japan Homer L.Dodge Department of Physics and Astronomy University of OklahomaNormanOklahoma 73019-2061USA Department of Physics Tohoku UniversitySendaiMiyagi 980-8578Japan

电阻式核磁共振(RDNMR)测量是1988年由德国马普所的von Klitzing研究小组针对GaAs二维电子气中少量核自旋的探测而提出的一种具有超高灵敏度的实验技术.目前,RDNMR已经成为研究单层或双层GaAs二维电子气核自旋和电子自旋特性的重要手段... 详细信息

电阻式核磁共振(RDNMR)测量是1988年由德国马普所的von Klitzing研究小组针对GaAs二维电子气中少量核自旋的探测而提出的一种具有超高灵敏度的实验技术.目前,RDNMR已经成为研究单层或双层GaAs二维电子气核自旋和电子自旋特性的重要手段.由于为实现电阻式核磁共振测量所建立的动态核极化方法强烈依赖于GaAs特有的材料属性,至今这一技术一直没有扩展应用到其他半导体低维系统中.最近,本研究小组发展了一种动态核极化新方法,成功实现了对典型窄带半导体锑化铟(InSb)二维电子气的电阻式核磁共振测量.本文在介绍电阻式核磁共振测量工作原理及已建立的典型动态核极化方法的基础上,着重讨论所提出的动态核极化新方法的机理、实验结果以及对今后研究的展望.

关键词：半导体二维电子气电阻式核磁共振测量动态核极化窄带半导体

An analysis of the chaotic motion of particles of different sizes in a gas fluidized bed

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Particuology 2008年第6期6卷 549-556页

作者： y.Q. Feng A.b. yu Lab for Simulation and Modelling of Particulate Systems School of Materials Science and Engineering University of New South Wales Sydney NSW 2052 Australia

The dynamic behavior of individual particles during the mixing/segregation process of particle mixtures in a gas fluidized bed is analyzed. The analysis is based on the results generated from discrete particle simulation, with the focus on the trajectory of and forces acting on individual particles. Typical particles are selected representing three kinds of particle motion： a flotsam particle which is initially at the bottom part of the bed and finally fluidized at the top part of the bed; a jetsam particle which is initially at the top part of the bed and finally stays in the bottom de-fluidized layer of the bed; and a jetsam particle which is intermittently joining the top fluidized and bottom de-fluidized layers. The results show that the motion of a particle is chaotic at macroscopic or global scale, but can be well explained at a microscopic scale in terms of its interaction forces and contact conditions with other particles, particle-fluid interaction force, and local flow structure. They also highlight the need for establishing a suitable method to link the information generated and modeled at different time and length scales.

关键词： Fluidization Segregation Discrete particle simulation Granular dynamics

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太湖16000年来沉积环境的演变

古生物学报 1996年第2期35卷 213-223页

作者：王建江水进刘金陵 William y.b.Chang 南京师范大学地理系中国科学院南京地质古生物研究所 CENTER FOR GREAT LUKES AND AQUATS SCIENCE AND SCHOOL OF NATURAL RESORCES AND ENVIRONMENT

通过对太湖钻孔岩芯岩性、结构、构造的剖析及粒度、磁化率的测试，发现冰后期东太湖形成于距今６５００年前。在距今６５００—５８００年，为一水深约２—３ｍ的、经常受到流水作用影响的浅水湖泊。距今约５８００—５７００年，东太... 详细信息

通过对太湖钻孔岩芯岩性、结构、构造的剖析及粒度、磁化率的测试，发现冰后期东太湖形成于距今６５００年前。在距今６５００—５８００年，为一水深约２—３ｍ的、经常受到流水作用影响的浅水湖泊。距今约５８００—５７００年，东太湖曾一度干枯或接近于干枯。距今５７００年以来湖泊变浅，平均水深只有１ｍ左右。由于湖泊变浅，湖底经常遭受波浪的扰动，形成波状层理或透镜状层理。西太湖局部洼地集水成湖的时间比东太湖早，并且水深比东太湖大。在５０００ａＢ．Ｐ，东、西太湖并未连通。东、西太湖的连通及太湖统一水体的形成开始于４０００—３５００ａＢ．Ｐ．。东太湖的成湖及东、西太湖的连通，湖面的扩大与水深的变浅，与冰期后海面上升引起的河谷与洼地沉积充填、淤塞有关。

关键词：太湖演变沉积环境成湖时代古地理学

Analysis of Mechanical Properties of Injection Molded Short Glass Fibre (SGF)/Calcite/AbS Composites

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Journal of Materials Science & Technology 1997年第5期13卷 389-396页

作者： Fu, S.y. Lauke, b. Institute for Polymer Research Dresden e.V 01069 Dresden Hohe Str.6 Germany

Acrylonitrile-butadiene-Styrene (AbS), with and without calcium carbonate (calcite) particles,was used as the matrix for reinforcement with as-received short-glass fibres (were originallytreated by the manufacturer) and sized short-glass fibres with two amino-silane coupling *** calcite particle content is 0, 11.7 and 23.5 vol. pct for the matrices. The glass fiber contentis 0, 10 and 15 vol. pct. The matrix materials and corresponding composites were compoundedusing a twin screw extruder and dumbbell-shaped tensile bars were prepared with an injectionmolding process. The tensile and flexural properties as well as the unnotched and notchedCharpy impact energies of short glass fibre/calcite/AbS composites were studied in this *** effects of fibres, fibre surface treatments and particles on these mechanical properties ofthe composites were discussed in detail. An importarit information was obtained, which is thatthe tensile and flexural strengths of hybrid SGF/calcite/AbS composites are the same as thoseof corresponding fibre composites when the ratio of the interfacial adhesion strength betweenparticles and matrix to that between fibres and matrix is higher than certain value. otherwise theformer are lower than the latter.

关键词： AbS Calcite/AbS Composites SGF Analysis of Mechanical Properties of Injection Molded Short Glass Fibre

Design and fabrication of computer-generated holograms for testing optical freeform surfaces

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Chinese Optics Letters 2013年第3期11卷 64-68页

作者：沈华朱日宏高志山 E. y. b. PUN W. H. Wong 朱效立 School of Electronic Engineering and Photo-Electric Technology Nanjing University of Science and Technology Department of Electronic Engineering City University of Hong Kong Key Laboratory of Nano-Fabrication and Novel Devices Integrated Technology Institute of Microelectronic of Chinese Academy of Sciences

Freeform optical surfaces （FOSs） will be the best elements in the design of compact optical systems in the future. However, it is extremely difficult to measure freeform surface with sufficient accuracy, which im- pedes the development of the freeform surface. The design and fabrication of computer-generated hologram （CGH） , which has been successfully applied to the tests for aspheric surfaces, cannot be directly adopted to test FOSs due to their non-rotational asymmetry. A novel ray tracing planning method combined with successively optimizing even and odd power coefficients of phase polynomials in turn is proposed, which can successfully design a non-rotational asymmetry CGH for the tests of FOSs with an F-O lens. A new eight-step fabrication process is also presented aiming to solve the problem that the linewidth on the same circle of the CGH for testing freeform surface is not uniform. This problem cannot be solved in the original procedure of CGH fabrication. The test results of the step profiler show that the CGH fabricated in the new nrocedure meets the reauirements.

关键词： Computer generated holography Design Electron holography Optical systems

Effect of ablation on the nonlinear spike growth for the single-mode ablative Rayleigh-Taylor instability

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Matter and Radiation at Extremes 2023年第1期8卷 53-62页

作者： J.y.Fu H.S.Zhang H.b.Cai P.L.yao S.P.Zhu Institute of Applied Physics and Computational Mathematics Beijing 100088People’s Republic of China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088People’s Republic of China Graduate School China Academy of Engineering PhysicsP.O.Box 2101Beijing 100088People’s Republic of China Science and Technology on Plasma Physics Laboratory Laser Fusion Research CenterCAEPMianyang 621900People’s Republic of China

The effect of ablation on the nonlinear spike growth of single-mode ablative Rayleigh–Taylor instability(RTI)is studied by two-dimensional numerical *** is shown that the ablation can reduce the quasi-constant velocity and significantly suppress the reacceleration of the spike in the nonlinear *** is also shown that the spike growth can affect the ablation-generated vorticity inside the bubble,which further affects the nonlinear bubble *** vorticity evolution is found to be correlated with the mixing width(i.e.,the sum of the bubble and spike growths)for a given wave number and ablation *** considering the effects of mass ablation and vorticity,an analytical model for the nonlinear bubble and spike growth of single-mode ablative RTI is developed in this *** is found that the nonlinear growth of the mixing width,induced by the single mode,is dominated by the bubble growth for small-scale ablative RTI,whereas it is dominated by the spike growth for classical RTI.

关键词： phase nonlinear bubble

Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan Q.Wang y.Chen W.b.yao C.Z.Xiao J.F.Myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational Mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering