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Phonon-blockade-based multiple-photon bundle emission in a quadratically coupled optomechanical system

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Frontiers of physics 2024年第3期19卷 207-215页

作者： Ye-Jun Xu hong xie Interdisciplinary Research Center of Quantum and Photoelectric Information Chizhou UniversityChizhou 247000China Department of Mathematics and Physics Fujian Jiangxia UniversityFuzhou 350108China

We propose a scheme to realize antibunched multiple-photon bundles based on phonon blockade in a quadratically coupled optomechanical *** adjusting the detunings to match the conditions of phonon blockade in the photon sidebands,we establish super-Rabi oscillation between zero-photon state and multiple-photon states with adjustable super-Rabi frequencies under appropriate single-phonon resonant *** the system dissipation into account,we numerically calculate the standard and generalized second-order functions of the cavity mode as well as the quantum trajectories of the state populations with Monte Carlo simulation to confirm that the emitted photons form antibunched multiple-photon ***,the desirable n-photon states are reconstructed after a direct phonon emission based on phonon blockade,and thus the single-phonon emission heralds the cascade emission of n-photon *** proposal shows that the optomechanical system can simultaneously behave as antibunched multiple-photon emitter and single-phonon *** a nonclassical source could have potential applications in quantum information science.

关键词： multiple-photon bundle emission phonon blockade optomechanical system

Electron-Phonon Interaction in an Annular Quantum Dot

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Communications in Theoretical Physics 2008年第2期49卷 493-503页

作者： WU Bo xie hong-Jing School of Physics and Electronic Engineering Guangzhou University Guangzhou 510006 China

The confined longitudinal-optical （LO） phonon and surface-optical （SO） phonon modes of a free-standing annular cylindrical quantum dot are derived within the framework of dielectric continuum approximation. It is found that there exist two types of SO phonon modes： top SO （TSO） mode and side SO（SSO） mode in a cylindrical quantum annulus. Numerical calculation on CdS annulus system has been performed. Results reveal that the two different solutions of SSO mode distribute mainly at the inner or outer surfaces of the annulus. The dispersion relations and the coupling intensions of phonons in a quantum annulus are compared with those in a cylindrical quantum dot. It is found that the dispersion relations of the two different structures are similar, but the coupling intension of the phonon-electron interaction in quantum annulus is larger than that in quantum dot. The Hamiltonians describing the free phonon modes and their interactions with electrons in the system are also derived.

关键词： dielectric continuum approximation phonon modes electron-phonon interaction annular quantum dots

Influence of lateral displacement on strip shape during cold rolling

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Journal of Iron and Steel Research International 2018年第9期25卷 892-900页

作者： Zhong-kai Ren hong Xiao hong-biao xie Xiao Liu College of Mechanical Engineering Yanshan UniversityQinhuangdao 066004 Hebei China National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004 Hebei China College of Mechanical Engineering Taiyuan University of Technology Taiyuan 030024 Shanxi China

The theory of metal plastic deformation is an important part of the strip shape control theories. In order to control the shape and gauge accurately during cold thin strip rolling, the mechanism of the metal lateral flow must be revealed clearly. Therefore, the lateral displacement of thin strip was studied by the grid method. Those grids with a line thickness of 10 μm and clear boundaries were successfully manufactured on the strip surface using lithography. Then, the effects of reduction, front and back tension, and taper angle of the first intermediate roll on the metal lateral flow were studied. The strip shape was calculated with and without considering the lateral displacement; furthermore, the calculations were compared with the measured results. The results show that the calculations with considering the lateral displacement are closer to the measured results. In addition, the comparison of finite element analysis results with the experimental results indicates that the test method was reliable.

关键词： Thin strip Lithography technology Lateral displacement Strip shape Experimental research Finite element simulation Cold rolling

Recurrence Formulas for the Mie Series

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Chinese Physics Letters 2011年第10期28卷 123-125页

作者： SUN Ji-Yu xie hong College of Information and Communication Engineering Harbin Engineering UniversityHarbin 150001 College of Measurement-Control Tech and Communications Engineering Harbin University of Science and TechnologyHarbin 150040

The Mie series has very important applications in electromagnetics(including optics).We employ a formulation for the Mie series which relies more on the derivatives of Legendre polynomials than Bessel *** formulas for derivatives related to Legendre polynomials are derived to realize the Mie series conveniently and to avoid treating special angles.

关键词： functions Legendre conveniently

Super-Elasticity Characteristics of TiNi Alloy Processed by Equal Channel Angular Extrusion

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稀有金属材料与工程 2009年第A3期38卷 123-128页

作者： Fan Zhiguo Jiang hong xie Chaoying Shanghai Jiaotong University Shanghai 200240 China

A Ni-rich TiNi alloy was processed by Equal Channel Angular Extrusion (ECAE) at 500℃. After four passes ECAE treatment, microstructure of the alloy was refined but slightly inhomogeneous, to sub-micron scale, approximately 0.5～0.6 μm. Comparing with the solution-treated TiNi specimen, the martensitic transformations start (Ms) and peak temperatures (Mp) of TiNi specimens processed by ECAE were dramatically lowered. After ECAE treatment, the R-phase transformation was stimulated and separated from martensitic transformation, but occurred within a larger temperature range. Super-elasticity characteristics of TiNi alloy were tested by tensile loading and unloading cycles. The results revealed that at a tensile strain of 6% or smaller, TiNi alloy processed by four passes ECAE showed better super-elasticity, with less residual strain retained, than solution-treated sample. After tensile strain exceeded 6%, up to 8%, the maximum recoverable strain of TiNi alloy ECAE treated was decreased. Microstructure evolution and its effect on phase transformations and super-elasticity characteristics were discussed.

关键词：钛镍合金物理性能熔点峰值温度

Global Existence and Nonexistence for a Strongly Coupled Parabolic System with Nonlinear Boundary Conditions

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1297-1304页

作者： You Peng CHEN Chun hong xie Department of Mathematics Nanjing Normal University Nanjing 210097 P. R. China Department of Mathematics Yancheng Normal Institute Yancheng 224002 P. R. China Department of Mathematics Nanjing University Nanjing 210093 P. R. China

This paper deals with the strongly coupled parabolic system ut = v^m△u, vt = u^n△v, （x, t） ∈Ω × （0,T） subject to nonlinear boundary conditions 偏du/偏dη = u^αv^p, 偏du/偏dη= u^qv^β, （x, t） ∈ 偏dΩ × （0, T）, where Ω 包含 RN is a bounded domain, m, n are positive constants and α,β, p, q are nonnegative constants. Global existence and nonexistence of the positive solution of the above problem are studied and a new criterion is established. It is proved that the positive solution of the above problem exists globally if and only if α 〈 1,β 〈 1 and （m ＋p）（n ＋ q） ≤ （1 - α）（1 -β）.

关键词： Strongly coupled Global existence Finite time blow-up Upper and lower solutions

Ectopic Expression of the Pttknl Gene Induces Alterations in the Morphology of the Leaves and Flowers in Petunia hybrida Vilm.

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Journal of Integrative Plant Biology 2005年第10期47卷 1153-1158页

作者： Xin HU Qing-Feng WU Ya-hong xie hong RU Feng xie Xin-Yu WANG Chong-Ying WAN School of Life Sciences Lanzhou University Lanzhou 730000 China Xi＇an Institute of Gardens Xi＇an 710065 China

A novel knottedl-like homeobox （knox） gene, Pttknl （Populus tremulaxtremuloides knottedl）, isolated from the cambial region of hybrid aspen, was introduced into Petunia hybrida Vilm. using the leafdisc method mediated by Agrobacterium. A series of novel phenotypes was observed in transgenic petunia plants, including the formation of ectopic spikes on the adaxial surface of corollas and small petals on the abaxial surface of corollas, fusion of floral organs, shortening of corolla midribs, the formation of tumor-like knots along the midrib on the abaxial surface and serrated lobs of corolla margins, and alterations in petal color; except for changes in the leaves and plant architecture, RT-PCR showed that the Pttknl gene was expressed in the leaves of different petunia transgenic plants, whereas no signal was detected in wild-type plants. The possible function of Pttknl in leaf and flower development is discussed.

关键词： ectopic expression knox gene novel phenotypes Petunia hybrida Pttknl gene RT-PCR.

Seismic Deformation and Seismic Resistance Analysis of Shapai Roller Compacted Concrete Arch Dam Based on Field Monitoring and Dynamic Finite Element Method

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Journal of Mountain Science 2013年第1期10卷 137-148页

作者： ZHUO Li HE Jiang-da xie hong-qiang College of Water Resources and Hydroelectricity Sichuan University State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

Shapai Roller Compacted Concrete(RCC) Arch Dam is the highest RCC arch dam of the 20th century in the world with a maximum height of 132m,and it is the only concrete arch dam near the epicentre of Wenchuan earthquake on May 12th,*** seismic damage to the dam and the resistance of the dam has drawn great *** paper analyzed the response and resistance of the dam to the seismic wave using numerical simulations with comparison to the monitored *** field investigation after the earthquake and analysis of insitu data record showed that there was only little variation in the opening size at the dam and foundation interface,transverse joints and inducing joints before and after the *** overall stability of the dam abutment resistance body was quite good except a little relaxation was *** results of the dynamic finite element method(FEM) showed that the sizes of the openings obtained from the numerical modeling are comparable with the monitored values,and the change of the opening size is in millimeter *** study revealed that Shapai arch dam exhibited high seismic resistance and overload capacity in the Wenchuan earthquake *** comparison of the monitored and simulated results showed that the numerical method applied in this paper well simulated the seismic response of the *** method could be useful in the future application on the safety evaluation of RCC dams.

关键词： Deformation monitoring Nonlinear dynamic finite element analysis RCC arch dam Wenchuan earthquake Power station

Numerical estimation of choice of the regularization parameter for NMR T2 inversion

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Petroleum Science 2016年第2期13卷 237-246页

作者： You-Long Zou Ran-hong xie Alon Arad State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249China Shell International Exploration and Production Inc. Houston 77079 TX USA

Nuclear Magnetic inversion is the basis of NMR Resonance （NMR） T2 logging interpretation. The regularization parameter selection of the penalty term directly influences the NMR T2 inversion result. We implemented both norm smoothing and curvature smoothing methods for NMR T2 inversion, and compared the inversion results with respect to the optimal regular- ization parameters （（Xopt） which were selected by the dis- crepancy principle （DP）, generalized cross-validation （GCV）, S-curve, L-curve, and the slope of L-curve methods, respectively. The numerical results indicate that the DP method can lead to an oscillating or oversmoothed solution which is caused by an inaccurately estimated noise level. The （Xopt selected by the L-curve method is occa- sionally small or large which causes an undersmoothed or oversmoothed T2 distribution. The inversion results from GCV, S-curve and the slope of L-curve methods show satisfying inversion results. The slope of the L-curve method with less computation is more suitable for NMR T2 inversion. The inverted T2 distribution from norm smoothing is better than that from curvature smoothing when the noise level is high.

关键词： NMR T2 inversion Tikhonov regularizationVariable substitution Levenberg-Marquardt method Regularization parameter selection