检索结果-南通市图书馆

Giant excitonic upconverted emission from two-dimensional semiconductor in doubly resonant plasmonic nanocavity

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2022年第7期11卷 1523-1534页

作者： Pengfei Qi Yuchen Dai Yang Luo Guangyi Tao Liheng Zheng Donglin Liu Tianhao Zhang Jiadong Zhou Bo Shen Feng Lin Zheng Liu Zheyu Fang School of Physics State Key Laboratory for Mesoscopic PhysicsAcademy for Advanced Interdisciplinary StudiesCollaborative Innovation Center of Quantum MatterNano-optoelectronics Frontier Center of Ministry of EducationPeking UniversityBeijing 100871China Institute of Modern Optics Nankai UniversityTianjin Key Laboratory of Micro-scale Optical Information Science and TechnologyTianjin 300350China Photonics Research Center School of PhysicsMOE Key Lab of Weak-Light Nonlinear Photonicsand Tianjin Key Lab of Photonics Materials and Technology for Information ScienceNankai UniversityTianjin 300071China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore

Phonon-assisted upconverted emission is the heart of energy harvesting,bioimaging,optical cryptography,and optical *** has been demonstrated that emerging two-dimensional(2D)semiconductors can provide an excellent platform for efficient phonon-assisted upconversion due to the enhanced optical transition strength and phonon-exciton interaction of 2D ***,there is little research on the further enhancement of excitonic upconverted emission in 2D ***,we report the enhanced multiphoton upconverted emission of 2D excitons in doubly resonant plasmonic *** to the enhanced light collection,enhanced excitation rate,and quantum efficiency enhancement arising from the Purcell effect,an upconverted emission amplification of>1000-fold and a decrease of 2~3 orders of magnitude in the saturated excitation power are *** findings pave the way for the development of excitonic upconversion lasing,nanoscopic thermometry,and sensing,revealing the possibility of optical refrigeration in future 2D electronic or excitonic devices.

关键词： converted resonant doubly

A doubly Achromatic Two-magnet Nonuniform Field Bending System of 270° in Deflection

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese journal of nuclear physics 1995年第2期17卷 179-184页

作者： Wang Houwen(Department of Physics,Nanjing University,Nanjing 210008) Nanjing Univ Nanjing China

A new doubly achromatic two-magnet beam bending system is *** of two nonuniform dipoles separated by a small drift *** doublyachromatic relations are *** system showed excellent achromatic and focusingproperties and good quality of electron beam with small *** small diver-gence and axial symmetry were produced at the output of the *** system isspecially suitable for low energy electron linac beam with large energy spread.

关键词： 270° doubly achromatic deflection Two nonuniform field dipoles Small and axial symmetric beam

Phase–amplitude model for doubly fed induction generators

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2019年第2期7卷 369-379页

作者： Hua HUANG Ping JU Xueping PAN Yuqing JIN Xiaoming YUAN Yuan GAO State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China College of Energy and Electrical Engineering Hohai UniversityNanjing 210098China

The doubly fed induction generator(DFIG) is major type of wind turbine generator used in grid-connected wind farms. Practical models of DFIG have been built to study the influence of wind power generation on power system dynamics. However, most existing practical models of the DFIG are based on rectangular coordinates,in which frequency variation is neglected. In this paper, a phase-amplitude(P-A) model is proposed for a DFIG based on phase and amplitude of the internal voltage. The model structure is much like that of the synchronous generator, and the rotor voltage can manipulate both the amplitude and the phase of the internal *** have been made between the new P-A model of the DFIG and the synchronous generator model,as well as the asynchronous motor *** contributions of the new P-A model of the DFIG are discussed and it is demonstrated that the proposed model has better ability in describing power system dynamic phenomena such as voltage dynamics and structural dynamics. Simulation results and a field test validate these contributions.

关键词： doubly fed induction generator(DFIG) Model Internal voltage Voltage dynamics Frequency dynamics

Behavior and functional modeling methods of doubly salient electromagnetic generators for aircraft electrical power system applications

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2019年第2期32卷 477-488页

作者： Yanwu XU Zhuoran ZHANG Li YU Yuke SHI Center for More Electric Aircraft Power System Nanjing University of Aeronautics and Astronautics

The doubly Salient Electromagnetic Generator(DSEG) is a promising candidate in aircraft generator application due to the simplicity, robustness and reliability. However, the field windings and the armature windings are strongly coupled, which makes the inductance characteristics non-linear and too complex to model. The complex model with low precision also leads to difficulties in modeling and analysis of the entire aircraft Electrical Power System(EPS). A behavior level modeling method based on modified inductance Support Vector Machine(SVM) is proposed. The Finite Element Analysis(FEA) inductance data are modified based on the experiment results to improve the precision. A functional level modeling method based on input–output characteristics SVM is also proposed. The two modeling methods are applied to a 9 kW DSEG prototype. The steady state and transient process precision of the proposed methods are proved by comparing with the experiment results. Meanwhile, the modeling time consumption, the application time consumption and the calculation resource demand are compared. The DSEG behavior and functional modeling methods provide precious results with high efficiency, which accelerates theoretical analysis and expands the application foreground of the DSEG in the aircraft EPS.

关键词： Behavior modeling doubly salient electromagnetic machine Functional models Non-linear analysis Support vector machines

Design,analysis and control of hybrid excited doubly salient stator-permanent-magnet motor

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2010年第1期53卷 188-199页

作者： ZHU XiaoYong1,2 & CHENG Ming1 1 Engineering Research Center for Motion Control of MOE,School of Electrical Engineering,Southeast University,Nanjing 210096,China 2 School of Electrical and Information Engineering,Jiangsu University,Zhenjiang 212013,China 1. Engineering Research Center for Motion Control of MOE School of Electrical Engineering Southeast University Nanjing 210096 China2. School of Electrical and Information Engineering Jiangsu University Zhenjiang 212013 China

In this paper,a new hybrid excited doubly salient stator-permanent-magnet motor is proposed,where both permanent magnets and DC field windings are located in the *** theory,the mathematical model and design method of the motor are *** corresponding output power equation and the relationship between the flux control capability and the extended speed range are deduced in *** using an efficient "one-step" three-dimensional(3D) finite element method,the electromagnetic performances are analyzed,in which the leakage flux outside the stator circumference and end-effect are taken into *** on the operation principle of the motor,the control strategy and scheme are developed and implemented *** experimental results and finite element analysis show that the proposed motor not only maintains the advantages of doubly salient permanent magnet motors,but also offers high energy efficiency over a wide speed range,which makes the motor an interesting candidate for electric vehicles.

关键词： stator permanent magnet motor hybrid excitation doubly salient finite element method flux weakening control

A Consistency Check for the Free Scalar Field Theory Realization of the doubly Spacial Relativity

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2019年第6期71卷 677-684页

作者： Mohsen Khodadi Kourosh Nozari Young Researchers and Elite Club Firoozkooh BranchIslamic Azad UniversityFiroozkoohIran Department of Physics Faculty of Basic SciencesUniversity of MazandaranP.O.Box47416-95447BabolsarIran Research Institute for Astronomy and Astrophysics of Maragha(RIAAM) P.O.Box55134-441MaraghaIran

We study a free scalar field theory in the framework of the Magueijo-Smolin model of the 'doubly Special Relativity'(DSR) which is a non-linear realization of the action of the Lorentz group on momentum space admitting an invariant energy cutoff. We show that unlike the standard quantum field theory, the Klein-Gordon equation obtained via Euler-Lagrange field equation and Heisenberg picture equation of motion of the field are not equivalent in this framework,at least up to the first order of the Planck length scale.

关键词： quantum gravity phenomenology doubly special relativity quantum field theory Klein-Gordon equation

Dirac Oscillator Under the New Generalized Uncertainty Principle From the Concept doubly Special Relativity

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2019年第11期71卷 1301-1303页

作者： S.Sargolzaeipor H.Hassanabadi W.S.Chung Faculty of Physics Shahrood University of TechnologyShahroodIran Department of Physics and Research Institute of Natural Science College of Natural ScienceGyeongsang National UniversityJinju 660-701Korea

We discuss one-dimensional Dirac oscillator, by using the concept doubly special relativity. We calculate the energy spectrum by using the concept doubly special relativity. Then, we derive another representation that the coordinate operator remains unchanged at the high energy while the momentum operator is deformed at the high energy so that it may be bounded from the above. Actually, we study the Dirac oscillator by using of the generalized uncertainty principle version and the concept doubly special relativity.

关键词： Dirac equation generalized uncertainty principle doubly special relativity

LHCb gets closer to discovering the second doubly charmed baryon

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2020年第2期63卷 25-26页

作者： Marek Karliner Jonathan L.Rosner School of Physics and Astronomy Tel Aviv UniversityTel Aviv 69978Israel Enrico Fermi Institute and Department of Physics University of ChicagoChicagoIL 60637USA

Recently the LHCb Collaboration [1] published the results of a search for the doubly charmed baryon ■. No significant signal is seen in the mass range from 3.4 to3.8 Ge V. To put this result in context, the ■baryon was seen by LHCb in decay modes ΛcK-π^+π^+[2](2017) and ■^+cπ^+[3](2018). The weighted average of the ■^++cc mass is 3621.24±0.65 (stat.)±0.31 (syst.) MeV [3].

关键词： doubly closer LHCb

An analytic electromagnetic calculation method for performance evolution of doubly fed induction generators for wind turbines

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2013年第10期20卷 2763-2774页

作者：张文娟黄守道高剑 CHEN Zhe College of Electrical and Information Engineering Hunan University Institute of Energy Technology Aalborg University

An analytic electromagnetic calculation method for doubly fed induction generator(DFIG) in wind turbine system was presented. Based on the operation principles, steady state equivalent circuit and basic equations of DFIG, the modeling for electromagnetic calculation of DFIG was proposed. The electromagnetic calculation of DFIG was divided into three steps: the magnetic flux calculation, parameters derivation and performance checks. For each step, the detailed numeric calculation formulas were all derived. Combining the calculation formulas, the whole electromagnetic calculation procedure was established, which consisted of three iterative calculation loops, including magnetic saturation coefficient, electromotive force and total output power. All of the electromagnetic and performance data of DIFG can be calculated conveniently by the established calculation procedure, which can be used to evaluate the new designed machine. A 1.5 MW DFIG designed by the proposed procedure was built, for which the whole type tests including no-load test, load test and temperature rising test were carried out. The test results have shown that the DFIG satisfies technical requirements and the test data fit well with the calculation results which prove the correctness of the presented calculation method.

关键词： electromagnetic calculation doubly fed induction generator(DFIG) wind turbine