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Dielectric and infrared properties of SrTiO_3 single crystal doped by 3d (V,Mn,Fe,Ni) and 4f (Nd,Sm,Er) ions

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Chinese Physics B 2014年第2期23卷 369-374页

作者： S.Maletic D.Maletic I.Petronijevic j.Dojcilovic D.M.Popovic Faculty of Physics University of Belgrade Institute of Physics University of Belgrade

In this study, the effects of doping by 3d （V, Mn, Fe, Ni） and 4f （Nd, Sm, Er） ions on dielectric and infrared properties of SrTiO3 （sto） single crystals are investigated. It is well known that doping of the SrTiO3 can change the dielectric properties of the sto from an insulator to an n-type semiconductor, and even to a metallic conductor. Dielectric and infrared （IR） properties of the undoped sto and doped sto single crystals are analyzed using dielectric spectroscopy （80 kHz-5 MHz）, transmission （200 cm^-1-4000 cm^-1）, and reflection spectroscopy （50 cm^-1-2000 cm^-1）. It is found that doping by the 3d ions reduces the value of dielectric permittivity, but the trend of temperature dependence of the dielectric permittivity remains almost unchanged. On the other hand, dielectric spectroscopy measurements for samples doped by 4f ions show the anomalous behaviors of the dielectric permittivity at temperatures around the temperature of the structural phase transition. There are two fractures of temperature dependences of inverse dielectric permittivity εr^-1 （T）. Transmittance spectroscopy measurements show that there are differences in the shape of the spectrum in the mid-IR region between the undoped sto and the one doped by 4f ions. The differences in the reflectance spectrum between the sto：Nd and sto are analyzed in detail.

关键词： doping dielectric properties phase transitions infrared spectroscopy

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Laparoscopic surgery for benign and malign diseases of the digestive system:Indications,limitations,and evidence

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World journal of Gastroenterology 2014年第17期20卷 4883-4891页

作者： Markus Alexander Küper Friederike Eisner Alfred K?nigsrainer j?rg Glatzle Department for General and Visceral Surgery Bundeswehr Hospital BerlinD-10115 BerlinGermany Department for General Visceral and Transplant SurgeryUniversity Hospital Tübingen72076 TübingenGermany

The laparoscopic technique was introduced in gastrointestinal surgery in the mid 1980s. Since then, the development of this technique has been extraordinary. Triggered by technical innovations (stapling devices or coagulation/dissecting devices), nowadays any type of gastrointestinal resection has been successfully performed laparoscopically and can be performed laparoscopically dependent on the patient’s condition. This summary gives an overview over 30 years of laparoscopic surgery with focus on today’s indications and evidence. Main indications remain the more common procedures, e.g., appendectomy, cholecystectomy, bariatric procedures or colorectal resections. For all these indications, the laparoscopic approach has become the gold standard with less perioperative morbidity. Regarding oncological outcome there have been several high-quality randomized controlled trials which demonstrated equivalency between laparoscopic and open colorectal resections. Less common procedures like esophagectomy, oncological gastrectomy, liver and pancreatic resections can be performed successfully as well by an experienced surgeon. However, the evidence for these special indications is poor and a general recommendation cannot be given. In conclusion, laparoscopic surgery has revolutionized the field of gastrointestinal surgery by reducing perioperative morbidity without disregarding surgical principles especially in oncological surgery.

关键词： Laparoscopy Gastrointestinal surgery Esophagus stomach Cholecystectomy Colorectal surgery Liver resection Pancreas resection Laparoscopic resection of gastrointestinal

A Cell-Based Smoothed Finite Element Method for Modal Analysis of Non-Woven Fabrics

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Computers, Materials & Continua 2021年第6期67卷 2765-2795页

作者： Nguyen T.Quyen N.Dourado A.j.P.Gomes F.B.N.Ferreira C2T—Centro de Ciência e Tecnologia Têxtil Departamento de Engenharia TêxtilUniversidade do MinhoCampus de AzurémGuimarães4804-533Portugal CMEMS-UMinho Departamento de Engenharia MecânicaUniversidade do MinhoCampus de AzurémGuimarães4804-533Portugal Department of Computer Science Universidade da Beira InteriorConvento de Sto.AntónioCovilhã6201-001Portugal Instituto de Telecomunicações R.Marquês deÁvila e BolamaCovilhã6201-001Portugal

The combination of a 4-node quadrilateral mixed interpolation of tensorial components element(MITC4)and the cell-based smoothed finite element method(CSFEM)was formulated and implemented in this work for the analysis of free vibration and unidirectional buckling of shell *** formulation was applied to numerous numerical examples of non-woven *** CSFEM schemes do not require coordinate transformation,spurious modes and numerical instabilities are prevented using bilinear quadrilateral element subdivided into two,three and four smoothing *** improvement of the original CSFEM formulation was made regarding the calculation of outward unit normal vectors,which allowed to remove the integral operator in the strain smoothing *** procedure conducted both to the simplification of the developed formulation and the reduction of computational cost.A wide range of values for the thickness-to-length ratio and edge boundary conditions were *** developed numerical model proved to overcome the shear locking phenomenon with success,revealing both reduced implementation effort and computational cost in comparison to the conventional FEM *** cell-based strain smoothing technique used in this work yields accurate results and generally attains higher convergence rate in energy at low computational cost.

关键词： Mindlin-Reissner theory of plates shear-locking gradient/strain smoothing technique non-woven fabric

Study on a novel optical readout ferroelectric devicebased on MIS for uncooled infrared imaging

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Study on a novel optical readout ferroelectric devicebased o...

ATHYS模型及其在巢湖流域丰乐河水文过程模拟中的应用

2007亚洲光电子会议先进传感与图象材料及器件分会场

作者： j. H. Qin* j. H. Ma Z. M. Huang and j. H. ChuNational Laboratory for Infrared Physics Shanghai Institute ofTechnical Physics Chinese AcademyofSciences Shanghai 200083 China

Both conventional reflectance and electric modulation reflectance of MIS structures: Pt/BLT/Si and Pt/sto/Si areinvestigated under different bias voltage in visible band. To make the study for a novel type of infrared imaging devicewith optical readout, we describe theoretically the regularity of bias voltage-induced reflectivity change of MIS usingDrude plasmon effect model and employ the electric modulation to enhance the sensitivity and resolution of reflectancespectrum of MIS. To improve the SNR for reflectance measurement, we design a dual-optical-path and dual-modulatingexperiment instrument. A tandem demodulation technique is adopted with two lock-in amplifiers to achieve preciseresults. Some more sensitive optical band for optical readout and the voltage value interval causing fastest change rateare found. With the MIS-based research, we bring out the possibility of forming the MFIS device for infrared imaging byattaching a ferroelectric layer PZT to MIS structure. The detecting principle of MFIS device is briefly introduced.

关键词： MIS voltage-controlled change of reflectivity electric modulation bias voltage

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安徽农业大学学报 2014年第6期41卷 1061-1069页

作者：郑珊珊 Perrin j L 储茵马友华 Salles C Tournoud M G 安徽农业大学资源与环境学院合肥230036 Université Montpellier 2. HydroSciences Montpellier(UMR 5569) France

以巢湖典型支流丰乐河流域为例,利用分布式水文模型ATHYS对流域降雨—径流过程进行模拟,以期为丰乐河流域水土保持、防洪、水资源利用和非点源污染防治等提供科学依据。ATHYS模型将流域分为大小相同的空间小单元,以库模型进行产流计算,... 详细信息

以巢湖典型支流丰乐河流域为例,利用分布式水文模型ATHYS对流域降雨—径流过程进行模拟,以期为丰乐河流域水土保持、防洪、水资源利用和非点源污染防治等提供科学依据。ATHYS模型将流域分为大小相同的空间小单元,以库模型进行产流计算,以滞后演算法(lag and route)方法进行汇流计算,并以Nash and Sutcliffe指数作为检验模拟结果的标准,模拟流域出口断面日径流量,初步分析流域径流实测值与模拟值的年际变化。模型模拟结果表明,在率定期和验证期模拟与实测径流量的总Nash and Sutcliffe值(Nash值)都可以达到0.80以上,相关系数均可达0.89以上。除了部分峰值和基流,模型能较好地模拟丰乐河的径流过程。模型模拟径流总量的相对误差在率定期为23.1%,验证期为34.6%。流域降雨量、径流量的年内、年际变化均比较明显,径流实测值和模拟值的年际变化也都比较大。综合来看,模型比较适用于所研究流域的日径流模拟。

关键词：降雨径流水文模拟 ATHYS模型丰乐河流域

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胃癌患者生活质量问卷(QLQ-sto22)中文版的制定

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中国心理卫生杂志 2005年第5期19卷 310-312页

作者：姜宝法徐涛刘春晓徐敏崔永春王家林杜君 j.Blazyby 山东大学公共卫生学院 250012 中国协和医科大学基础医学院医学统计室山东省肿瘤医院欧洲癌症治疗与研究组织生存质量研究组

目的:将QLQ-sto22引入国内,并评价其可行性、信度和效度。方法:以2003年6月1日至12 月31日在某市三家医院入院治疗的胃癌患者为研究对象。调查内容主要包括一般状况、简明病情调查表及QLQ-sto22。结果:重复测量前后比较,sto22量表各个... 详细信息

目的:将QLQ-sto22引入国内,并评价其可行性、信度和效度。方法:以2003年6月1日至12 月31日在某市三家医院入院治疗的胃癌患者为研究对象。调查内容主要包括一般状况、简明病情调查表及QLQ-sto22。结果:重复测量前后比较,sto22量表各个维度的ICC 值均大于0.75;Cronbaeh'a 系数为0.80; 量表的分半信度系数分别为0.78。表明量表的重测信度、分半信度和内部一致性良好。对sto22量表的各个维度做因子分析,得到3个因子,它们分别能解释总体方差的72.8%,各公共因子在相应项目上的因子载荷均>0. 5,表明该量表具有较满意的结构效度。结论:QLQ-sto22中文版具有较好的信度和效度。

关键词：胃癌生活质量问卷 QLQ-sto22 中文版制定

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估算现有凝汽器性能的计算器程序

四川电力技术 1986年第2期 34-40页

作者： TVERBER,j.C. 杨开明江油电厂

任何一个曾作过现有凝汽器性能或换管估算的人,都深感此工作繁复乏味,要多次地试探计算才能确定其尺寸和工况。管材、污垢系数、水流量或进水温度改变后,怎样再核算背压的变化、泵水要求,到目前都是恼人的事。而可编程计算器问

关键词：凝汽器管 ITD TR 温升 RCL 常数数学 sto 计算器程序 TTD OP 方程式方程修正系数性能计算英热单位压头损失

An Improved ICCG Method of Large-Scale Sparse Linear Equation Group

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An Improved ICCG Method of Large-Scale Sparse Linear Equatio...

Micro—structural analysis of YBa2Cu3O7—x thin films grown on different substrates by X—ray techniques

The 10th EPMESC

作者： Y. j. Zhang * Q. Sun School of Aeronautics Northwestern Polytechnical University Xi’an 710072 China

Coefficient matrix of linear equations from finite element method (FEM) is sparse and symmetrical. For the sake of CPU operational time saving to accesses data in matrix decomposition and reducing sto

关键词： large-scale sparse linear equation group fully sparse strategy improved ICCG method.

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Beijing Synchrotron Radiation Facility 2001年第2期 54-60页

作者： C.X.Liu M.Xu W.H.Tang X.M.Chen L.S.Wu N.Yang Z.H.Mai K.Tao j.G DepartmentofMaterialsScience TsinghuaUniversityBeijing100083china DepartmentofPhysics TheUniversityofHongKongPokfulamRoadHongKongchina InstituteofPhysicsandCenterforCondensedMatterPhysics Chinese

YBa2Cu3Ox(YBCO) thin films grown on different substrates with and/or without Eu2CuO4(ECO) buffer layer were investigated by X-ray wide angle diffraction,reflection,diffuse scattering and *** show that for the yttria stabilized ZrO2(YSZ) substrate,the presence of an ECO buffer layer improves the crystalline quality of the YBCO film,while a negative effect is observed for the SrTiO3(sto) *** lateral correlation length for a sample grown on a YSZ substrate with ECO buffer Layer is much greater than grown on an sto *** sto substrate used has mosaic structure.2001 Elsevier Science *** rights reserved.

关键词：微观结构 X射线衍射分析 YBa2Cu3O7薄膜钇钡铜复合氧化物薄膜缓冲层薄膜生长