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Upconversion Emission Properties of Erbium-and Ytterbium-Doped Potassium Lithium Tantalate Niobate Ceramics

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Chinese Physics Letters 2013年第12期30卷 116-119页

作者： LI Lei zhou zhong-xiang YANG Wen-Long LI Huan WU Ye Jiangsu Key Laboratory of Power Transmission and Distribution Equipment Technology Hohai UniversityChangzhou 213022 Department of Physics Harbin Institute of TechnologyHarbin 150001

We investigate the luminescence properties of erbium-doped and erbium-ytterbium-codoped potassium lithium tantalate niobate ceramics prepared by the solid phasesyntheses *** crystalline structure and surface morphology of these ceramics are tested by x-ray diffraction and scanning electron *** green,red,and near-infrared upconversion photoluminescence properties are analyzed by the steady-state spectra under 975 nm and 800 nm *** ceramics arewell sintered and tetragonal tungsten type crystalline structure with the 4 mm point group and the P4bm space *** Er3+upconversion emission integrated intensities increase with theincrease in Er3+ion concentration,while the green emissiondecreases with the increase in Yb^(3+)ion concentration under the 800 nm *** effective energy back transfer process from the Er^(3+)^(4)S_(3/2)state to Yb^(3+)ground state plays an important role in enhancing the red emission and weakening the green emission.

关键词： ceramics crystalline Potassium

Relativistic Magnetosonic Solitary Wave in Magnetized Multi-Ion Plasma

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Communications in Theoretical Physics 2009年第6期51卷 1121-1124页

作者： WANG Yun-Liang zhou zhong-xiang LU Yan-Zhen NI Xiao-Dong SHEN Jiang ZHANG Yu Department of Physics School of Applied Science University of Science and Technology Beijing Beijing 100083 China Department of Physics Harbin Institute of Technology Harbin 150001 China

In the presence of an applied uniform magnetic field Bo, the properties of 2-dimensional （2D） magnetosonic solitary waves of relativistic amplitude in the plasma containing electron, light ions He^＋, and heavy ions O＋ are presented. In the weakly relativistic limit, a Kadomtsev Petviashvili （KP） equation is derived by reductive perturbation method. We give the N-soliton solution of the KP equation and find dromion solutions of a potential of the physical field. The interaction law of the dromions is obtained, which shows there is no exchange of energy, momentum, and angular momentum before and after interaction of the dromions except for phase shifts.

关键词： magnetosonic solitary wave magnetized plasma weakly relativistic

Structural, Electronic and Optical Properties of KTa_(0.5)Nb_(0.5)O_(3) Surface: A First-Principles Study

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Chinese Physics Letters 2012年第1期29卷 227-230页

作者： SUN Hong-Guo zhou zhong-xiang YUAN Cheng-Xun YANG Wen-Long WANG He Department of Physics Harbin Institute of TechnologyHarbin 150001 College of Pharmacy Heilongjiang University of Chinese MedicineHarbin 150040

The crystal surface properties of potassium tantalite niobate,KTa_(0.5)Nb_(0.5)O_(3) (KTN),are studied with firstprinciples calculation based on the density functional theory (DFT).Generalized gradient approximation (GGA) functional analysis is also employed by using CASTEP *** explanations for the differences of the ferroelectric and piezoelectric properties between the bulk and surface of the material are *** DFT with GGA is used to determine the structure and to calculate the electronic and optical properties of the chemically ordered KTa_(0.5)Nb_(0.5)O_(3) crystal (100),(110) and (111) *** results show that the surface properties are different from the bulk *** data obtained agree with the expected values and can serve as guidance for future experimental studies in the fields of photorefraction and nonlinear optics.

关键词： properties. crystal piezoelectric

Two-dimensional Perturbative Analysis of Slant Grating in Photorefractive Crystals in an External Electric Field

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Chinese Physics Letters 1998年第6期15卷 423-425页

作者： JIANG Yong-yuan FENG Yu-wen zhou zhong-xiang LI Yan SUN Xiu-dong XU Ke-bin Department of Applied Physics Harbin Institute of TechnologyHarbin 150001

A slant grating was recorded with two laser beams incident on photorefractive crystal in an external dc electric ***-dimensional perturbative analytical solution for the first two-order space-charge field for steady-state photorefractive slant grating recording has been *** is shown that the inclusion of the longitudinal component of the space-charge field during photorefractive two-wave coupling can predict reduction of the fundamental harmonic and enhancement or reduction of the second-order harmonic for various applied field strength and various grating slant *** dependence of the first two-order harmonics on the slant angle and on the applied field strength is examined.

关键词： Photorefractive Crystal harmonic

Perioperative treatment of femoral neck fracture with deep venous thrombosis： A case report

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Chinese Journal of Traumatology 2015年第2期18卷 109-112页

作者： Ming Liu Lei Liu Fuguo Huang Yue Fang Gang zhong zhou xiang Department of Orthopaedics West China Hospital of Sichuan University Chengdu 610041 China

Deep venous thrombosis （DVT） is an important cause of disability and mortality after major orthopedic surgery. The roles of perioperative treatment and prevention of DVT in patients with femoral neck fractures who require major surgery have not yet been well explored in Chinese clinical practice. Here we report a case of calf muscular venous thrombosis in a 55-year-old woman with femoral neck fracture before surgery. Preventive and treatment measures including the administration of heparin sodium, application of venous foot pump and placement of inferior vena cava filter were taken. The condition of the patient was stable during the perioperative period and the surgery was successful. Besides, postoperative examination showed that the femur healed well and the functional recovery was satisfactory. Our results suggest that femoral neck fracture patients combined with DVT can receive surgery after accurate preoperative assessment and proper preoperative treatment.

关键词： Femoral neck fractures Calf muscular venous thrombosis Venous thrombosis

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木框斜角榫接合性能研究

林产工业 2007年第6期34卷 20-22,25页

作者：周忠祥内蒙古农业大学林业工程学院

在木家具结构设计中,特别是具有中国传统家具风格的实木家具结构设计中,木框角部斜角榫接合强度是人们既关注又无法回避的问题。抗拉强度和抗弯强度是衡量木框斜角榫接合性能高低的两个重要指标。笔者对三种常用的、易于机械加工的斜角... 详细信息

在木家具结构设计中,特别是具有中国传统家具风格的实木家具结构设计中,木框角部斜角榫接合强度是人们既关注又无法回避的问题。抗拉强度和抗弯强度是衡量木框斜角榫接合性能高低的两个重要指标。笔者对三种常用的、易于机械加工的斜角榫接合试件的强度(抗拉强度,抗弯强度)进行了实验测定,并从各个方面对其进行比较、分析。研究结果表明:斜角榫接合形式,胶黏剂种类,加压时间等各个因子都不同程度地影响着木框角部接合的整体结构性能。单肩斜角明榫接合效果最好。

关键词：木框斜角榫接合强度

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Ar等离子体射流发射光谱诊断研究

发光学报 2019年第8期40卷 1049-1054页

作者：李磊陈晓东袁承勋周忠祥哈尔滨工业大学物理系黑龙江哈尔滨150001 上海机电工程研究所上海201109

为了深入了解大气压下Ar等离子体射流的产生机理和内部电子的状态,对Ar等离子体射流进行了发射光谱诊断,以玻尔兹曼斜率法对电子激发温度进行测算,利用发射光谱的连续谱绝对强度法测算出电子密度。通过设计一种可调节气压的金属针-环型... 详细信息

为了深入了解大气压下Ar等离子体射流的产生机理和内部电子的状态,对Ar等离子体射流进行了发射光谱诊断,以玻尔兹曼斜率法对电子激发温度进行测算,利用发射光谱的连续谱绝对强度法测算出电子密度。通过设计一种可调节气压的金属针-环型介质阻挡放电装置,研究了氩气压和放电功率对Ar等离子体射流的电子激发温度和电子密度的影响。结果表明,随着气压从6kPa升高到16kPa,电子激发温度从0.83eV下降到0.68eV,电子密度从4.45×1022m^-3减小到0.44×1022m^-3(波长648.06nm),且随着放电功率从0.1775W增大到1.7926W,电子激发温度从0.82eV升高到5.14eV,电子密度从0.27×1022m^-3增大到4.61×1022m^-3,而且电子密度较低时,电子激发温度的变化更明显。由此得出结论,氩气压和放电功率对电子激发温度不仅有直接影响,还有通过电子密度变化导致的间接影响,电子密度较低时,氩气压和放电功率对电子激发温度的影响会相对更大一些。同时,选用两个波长计算的电子密度结果很接近,验证了诊断结果的准确性。

关键词：等离子体射流发射光谱绝对强度电子激发温度电子密度

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A轴向生长各向异性单晶光纤的模式特征

黑龙江大学自然科学学报 2005年第2期22卷 163-171页

作者：周忠祥崔伟龙哈尔滨工业大学应用物理系黑龙江哈尔滨150001

分析了A轴向生长单晶光纤的电磁场方程、场的表达式、边界条件以及色散方程。数值分析了几个低阶模式的色散曲线和横向场分量的结构特性;精确求解了各向异性A轴向生长的单晶光纤的电磁场方程,得到了横向场分量的精确解。利用精确到一阶... 详细信息

分析了A轴向生长单晶光纤的电磁场方程、场的表达式、边界条件以及色散方程。数值分析了几个低阶模式的色散曲线和横向场分量的结构特性;精确求解了各向异性A轴向生长的单晶光纤的电磁场方程,得到了横向场分量的精确解。利用精确到一阶的边界条件,得到各向异性A轴向生长单晶光纤的色散方程。数值分析了强各向异性A轴向生长单晶光纤仅存在m阶基元模式时的色散曲线以及横向场分量的结构特性。

关键词： A轴向生长单晶光纤各向异性模式理论色散关系横向电场

Zn∶Fe∶LiNbO_3晶体二波耦合和相位共轭效应的研究

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光学技术 2009年第5期35卷 701-703,707页

作者：李潇王培吉周忠祥济南大学理学院济南250022 哈尔滨工业大学理学院哈尔滨100005

采用二波耦合和四波混频实验,研究了Zn:Fe:LN(Fe:0.03wt.%,Zn:5.0mol)晶体的光折变二波耦合衍射效率和长时间照射下透射光强随时间的动态变化行为,以及其相位共轭效应,分别测试了其二波耦合衍射效率和其相位共轭反射率,结果表明该晶体... 详细信息

采用二波耦合和四波混频实验,研究了Zn:Fe:LN(Fe:0.03wt.%,Zn:5.0mol)晶体的光折变二波耦合衍射效率和长时间照射下透射光强随时间的动态变化行为,以及其相位共轭效应,分别测试了其二波耦合衍射效率和其相位共轭反射率,结果表明该晶体的衍射率可达到56%,且其衍射效率随着其信号光的减小先增大后减小,相位共轭反射率随信号光的增大呈减小的趋势,最高共轭反射率可达到650%。

关键词：二波耦合四波混频衍射效率相位共轭光折变效应