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Study of Two-Mode Squeezed Magnetopolarons

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Communications in Theoretical Physics 2007年第4期47卷 747-751页

作者： zhang Yan-min cheng Ze Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

In this paper, we conduct an investigation into two-dimensional squeezed magnetopolarons. The Hamiltonian of magnetopolarons is dealt with two-mode squeezed states transformation, which is based on the Lee-Low-Pines and Huybrechts （LLP-H） canonical transformations. This method makes it possible to take account of the linear terms, bilinear ones of phonon operators, and the correlation between two longitudinal optical （LO） phonon modes. The energies of the ground state and excited states are evaluated by variational approach, and accurate results are obtained. Furthermore, the renormalized cyclotron masses for some possible transitions are discussed in detail.

关键词： magnetopolarons squeezed state electron-phonon interaction renormalized mass

Amplitude-Squared Squeezing in a Kerr-Nonlinear Blackbody

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Communications in Theoretical Physics 2007年第5期47卷 933-936页

作者： WU Zi-Xia cheng Ze zhang Yan-min cheng Zheng-Ze Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

We find that amplitude-squared squeezing of the photon field is present in a new blackbody, namely, a Kerr- nonlinear blackbody. The squeezing effect decreases as temperature T increases. The amount of the amplitude-squared squeezing in a Kerr-nonlinear blackbody is much larger than the corresponding squeezing in normal blackbody, and the degree of amplitude-squared squeezing is much larger than the amplitude squeezing for the same range of parameters in a Kerr-nonlinear blackbody.

关键词： Kerr-nonlinear blackbody amplitude-squared squeezing nonpolariton

INFLUENCING PARAMETERS OF FLOW-INDUCED STRUCTURAL DEFORMATION FOR A CIRCULAR TUBE

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Journal of Hydrodynamics 2009年第4期21卷 520-525页

作者： JIANG Bo TIAN Mao-cheng zhang Guan-min LI Bao-xing cheng Lin School of Energy Source and Power Engineering Shandong University Jinan 250061 China

Numerical simulations were carried out to study the effects of flow and structural parameters on structural deformation. The curves were obtained to show the structural stress and deformation varying with the flow and structural parameters. Meanwhile, the influence degree of these parameters was investigated by range analysis, and a fitting formula of the parameters and the maximum structural deformation in this model was obtained and thus the most influential parameter on structure safety was found. Results show that there is a great difference in their effect on the structural deformation for these flow and structural parameters. The influence degree of parameters is in a decreasing order for the pipe length, fluid velocity, pipe thickness, fluid density, pipe diameter, elastic modulus, Poisson ratio and fluid viscosity, among which the first four parameters play the major role. Besides, a proper parameter selection based on the influence degree shown in the fitting formula can provide an effective control of the structural deformation.

关键词： fluid and structure interaction flow-induced finite element

The Relation between the Magnetic Field and Spin Period of a Millisecond Pulsar

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Chinese Physics Letters 2013年第10期30卷 237-240页

作者： PAN Yuan-Yue WANG Na zhang cheng-min Xinjiang Astronomical Observatories Chinese Academy of SciencesUrumqi 830011 National Astronomical Observatories Chinese Academy of SciencesBeijing 100012

Based on the function of the accretion induced magnetic decay,the analytical relationship between the magnetic field B and spin period P of a millisecond pulsar(MSP)is investigated,from which the minimum spin period of about one millisecond can be *** this minimum spin period,the range of the neutron star(NS)radius is constrained in comparison with the measured spin period of ***,we also study the relation between the spin period and the accretion massΔM of the NS,and find that the minimum spin period is achieved with the accretion mass of about-0.2M⊙,while the bottom magnetic field of about 108 G is obtained.

关键词： second radius decay

K Parameter Analysis of the Radio Emission Region of Pulsars

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Chinese Physics Letters 1999年第1期16卷 74-75页

作者： WU Xin-ji KNYu zhang cheng-min WEN Xue-shi Department of Geophysics Peking Universityand Chinese Academy of Science-Peking University Joint Astrophysical CenterBeijing 100871 Department of Physics and Materials Science City University of Hong KongHong Kong Department of Physics Hebei University of TechnologyTianjin 300130 Beijing Planetarium Beijing 100044

Using a new method of multi-frequency of K parameter,we estimate the ratio of altitudes of radio emission region of pulsars at 430 and 1418 *** value of the ratio is 1.34±0.12 and the power law index of altitude-frequency is 0.24±*** is indicated that the lower radio frequencies originate further out and the emission region is radially narrow.

关键词： altitude Pulsar narrow

Fermi γ-Ray Pulsars: Spectral and Generation Order Parameters

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Chinese Physics Letters 2011年第8期28卷 356-359页

作者： CAI Yan A.Taani WANG Wei ZHAO Yong-Heng zhang cheng-min National Astronomical Observatories Chinese Academy of SciencesBeijing 100012

We examine the theory of generation order *** kinds of generation order parameters are introduced,which describe the production of high-energyγphotons in a cascade process *** find a correlation between the average power−law photon indexΓand spin−down rate.P in 38 common FERMIγ−ray pulsars,and find that the third generation order parameter,which implies that the magnetic field may have the most significant effect on the high-energyγphoton absorption in the cascade processes,is the best *** statistical work shows that the theory of generation order parameters can be applied to describe the theγ-ray pulsar radiation mechanisms in the cascade processes.

关键词： scenario Fermi theory

The Primary Study of the Construction of Small Diameter Tissue-engineered Blood Vessel

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生物医学工程学杂志 2005年第S1期22卷 19-20页

作者： Huai-Qing CHEN Xi-Xun YU Yi zhang min cheng(Institute of Biomedical Engineering, West China Center of Medical Science, Sichuan University, chengdu 610041, China)

咪哒唑仑复合瑞芬太尼辅助臂丛神经阻滞的临床观察

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现代预防医学 2011年第19期38卷 4098-4099+4102页

作者：张成敏河南省原阳县人民医院麻醉科

[目的]探讨咪哒唑仑复合瑞芬太尼辅助臂丛神经阻滞的临床效果。[方法]选择2009年3月～2010年6月期间行臂丛神经阻滞的患者86例,随机将患者分为研究组和对照组,每组43例。两组患者待麻醉效果确定后,对照组患者如发现镇痛不完善,可给予芬... 详细信息

[目的]探讨咪哒唑仑复合瑞芬太尼辅助臂丛神经阻滞的临床效果。[方法]选择2009年3月～2010年6月期间行臂丛神经阻滞的患者86例,随机将患者分为研究组和对照组,每组43例。两组患者待麻醉效果确定后,对照组患者如发现镇痛不完善,可给予芬太尼辅助镇痛或局麻药封闭阻滞,而研究组患者则给予咪哒唑仑和瑞芬太尼的复合治疗,并对两组患者的临床治疗效果等相关评价指标进行比较分析。[结果]与对照组患者相比,研究组患者在麻醉中的5、10、30min其MAP降低且HR减慢,差别均具有统计学意义(P﹤0.05),但都仍然处于正常范围内。研究组患者在麻醉中的5、10、30min的镇静和疼痛情况均显著改善,差别均具有统计学意义(P﹤0.05)。研究组患者的术后1h随访完全无记忆的比率显著提高,而记忆清楚的比率则显著降低,差别均具有统计学意义(P﹤0.05)。[结论]咪哒唑仑复合瑞芬太尼辅助臂丛神经阻滞,其疗效确切,效果显著,对于提高臂丛神经阻滞质量具有十分重要的临床意义。

关键词：咪哒唑仑瑞芬太尼臂丛神经阻滞

三峡库区消落带优势草本植物淹水后汞的释放特征

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环境科学 2017年第3期38卷 987-992页

作者：邓晗张翔张成王永敏王定勇西南大学资源环境学院重庆400715 重庆市三峡库区农业面源污染控制工程技术研究中心重庆400716 重庆市农业资源与环境研究重点实验室重庆400716

为研究三峡库区消落带植物淹水后汞的释放特征,选取狗牙根、酸模叶蓼、空心莲子草这3种优势草本植物在库区现场进行原位淹水试验,研究这3种植物淹水后总汞(THg)含量动态变化特征,分析其释放通量与速率,估算其THg释放负荷.结果表明,3种... 详细信息

为研究三峡库区消落带植物淹水后汞的释放特征,选取狗牙根、酸模叶蓼、空心莲子草这3种优势草本植物在库区现场进行原位淹水试验,研究这3种植物淹水后总汞(THg)含量动态变化特征,分析其释放通量与速率,估算其THg释放负荷.结果表明,3种植物在淹水过程中THg浓度的下降速率呈现先快后慢的趋势,表明淹水前期植物中THg随植物腐解快速释放,随后释放基本稳定.3种植物的THg释放量存在显著差异,且表现为酸模叶蓼>空心莲子草>狗牙根.3种植物的THg释放量可能受植物初始C/N和THg浓度的影响.植物初始C/N越高,单位质量THg释放量越小.而植物初始THg浓度越高,单位质量植物THg释放量越大.结合3种植物在三峡库区消落带的分布权重和生物量,估算出酸模叶蓼、空心莲子草、狗牙根完全分解后的THg释放负荷分别为167.31、78.13、88.33 mg·hm^(-2).

关键词：三峡库区消落带草本植物淹水汞