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Hlder Stability Estimate for an Inverse Parabolic Problem

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Advances in Manufacturing 2000年第4期4卷 284-287页

作者： XU Ding hua 1,2.1. department of mathematics, College of Sciences, Shanghai {2., Shanghai 2.0072. china 2. department of Computational Sciences and Systematic Engineering, East china Geological Institute, Linchuan 344000, Jiangxi Province

This paper deals with a parabolic system in a multi dimentional bounded domain ΩR n with the smooth boundary Ω. We discuss an inverse parabolic problem of determining the indirectly measurable internal heat distribution at any intermediate moment from the heat distribution measurements in arbitrary accessible subdomain ωΩ at some time interval. Our main result is the Hlder stability estimate in the inverse problem and the proof is completed with a Carleman estimate and a eigenfunction expansion for parabolic equations.

关键词： inverse parabolic problems heat conductivity equations Hlder stability Carleman estima

Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2. CHEN ZhengHao3 & ZHANG XiaoZhong4,5 1 Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education, Institute of Low Energy Nuclear Physics, Beijing Normal university, Beijing 100875, china 2.Beijing Radiation Center, Beijing 100875, china 3 Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, china 4 Key Laboratory of Advanced Materials of the Ministry of Education, department of Materials Science and Engineering, Tsinghua university, Beijing 100084, china 5 Beijing National Center for Electron Microscopy, Tsinghua university, Beijing 100084, china 1. Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China 2. Beijing Radiation Center Beijing 100875 China 3. Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 4. Key Laboratory of Advanced Materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing 100084 China 5. Beijing National Center for Electron Microscopy Tsinghua University Beijing 100084 China

The LaMn1-xTexO3+δ (x=0.1, 0.2. 0.3) were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4+, and Mn3+ ions are partly converted into Mn2. and Mn4+ due to the excess oxygen and Te doping. The magnetotransport associated with Mn2., Mn3+ and Mn4+ was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3+ is much larger or less than the sum of Mn2. and Mn4+; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3+ is close to the sum of Mn2. and Mn4+. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

DOUBLE SYNERGISTIC EFFECTS AND EXTRACTION KINETICS OF A MICELLE MIXED EXTRACTANT SYSTEM I DOUBLE(KINETIC AND THERMODYNAMIC)SYNERGISTIC EFFECTS AND EXTRACTION MECHANISMS

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中国有色金属学会会刊：英文版 1993年第4期3卷 19-23页

作者： Yu,Jingfen Huang,Ting department of Chemical Engineering,Qinghua university,Beijing 100084,{2.

The equilibria and kinetic characteristics of a micelle mixed extractant system-D2.EHPA-MPA（MPA-monoalkyl phosphoric acid with long carbon chain and micellization）in extractionof the Al3+ions were *** was found that... 详细信息

The equilibria and kinetic characteristics of a micelle mixed extractant system-D2./sub> EHPA-MPA（MPA-monoalkyl phosphoric acid with long carbon chain and micellization）in extractionof the Al3+ions were *** was found that the system has double synergistic effects on theextraction of the Al3+*** compositions of the synergistic complexes were determined andthe synergistic reaction equations were obtained.

关键词： D2.HPT-MPA mixed system double synergistic effects extraction kinetics extraction mechanism micelle mixed extractant system

THE COMPLEX VARIABLE BOUNDARY ELEMENT METHOD FOR SOLVING SANDWICH PLATE PROBLEMS

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Acta Mechanica Sinica 1990年第1期6卷 50-58页

作者： Gu Lei Huang Maokuang, department of Modern Mechanics, university of Science and Technology of{2. 1. department of Modern Mechanics University of Science and Technology of China China

The objective of this paper is to develop a new complex variable boundary element method for sand- wich plates of Reissner's type and Hoff's type. The general solution of Helmhotz equation in complex field is given. Based on the Vekua's complex integral representation of the analytic function, the new boundary integral equations are formulated. The density function in the integral equation is determined directly by boundary element method. Some standard examples are presented, and the results of numerical solutions are accurate everywhere in the plate. The approach presented is only applicable for bounded simply connected regions.

关键词： BEM sandwich plates Helmhotz equation

Direct Synthesis and Spectrum Analysis of CeO_2.Nanoparticles Deposited on Carbon Nanotubes

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Journal of Wuhan university of Technology(Materials Science) 2009年第1期24卷 34-37页

作者：张祖伟胡陈果 department of Applied Physics Chongqing University

A novel method of direct synthesis of CeO2.nanoparticles onto multi-walled carbon nanotubes （MWNTs） was developed with advantages of simplicity, ease of scale-up, and low costs. The size of CeO2.particles deposited on the MWNTs was less than 6 nm. SEM and TEM were em-ployed to analysis the CeO2.coated MWNTs, and the properties of FTIR spectrum and UV-vis ab-sorption spectrum were investigated. The functional groups on the MWNTs obtained by nitric acid treatment play an important role on the deposition of the CeO2.particles. The carbon nanotubes possess broadened UV absorption function after being coated with CeO2.nanopartilces.

关键词： nanocomposites chemical synthesis spectrum

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红树植物秋茄次生木质部生态解剖学的比较

台湾海峡 1998年第2期17卷 219-223,T001页

作者：林益明林建辉林鹏厦门大学生物系厦门361005

本文研究了不同纬度秋茄（Kandeliacandel）次生木质部的组织结构及数量特征。秋茄的导管多为梯纹导管。随着纬度的升高，温度下降，各分布区导管分子长度和导管直径呈现下降的趋势（深圳福田的秋茄导管分子长度、导管直径均是最大是个... 详细信息

本文研究了不同纬度秋茄（Kandeliacandel）次生木质部的组织结构及数量特征。秋茄的导管多为梯纹导管。随着纬度的升高，温度下降，各分布区导管分子长度和导管直径呈现下降的趋势（深圳福田的秋茄导管分子长度、导管直径均是最大是个例外）；穿孔板横隔的数目也随着纬度的升高而减少；盐度高（33）造成福建云霄竹塔的秋茄低导管分布频率、低单管孔率、低双管孔率；秋茄的射线分布频率随着纬度的升高而减少（海南东寨港除外）；不同纬度的导管分子长度（y）与纤维长度（x）有显著相关，相关系数r＝0．97、p＜0．01，回归方程为y＝－119．0＋0．6x；导管直径（y）与纤维长度（x）也有显著相关，相关系数r＝0．91、p＜0．02.回归方程为y＝7．99＋0056x。

关键词：秋茄次生木质部生态解剖红树植物

Torque model of hydro turbine with inner energy loss characteristics

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Science china(Technological Sciences) 2010年第10期53卷 2826-2832页

作者： ZENG Yun1,2. GUO YaKun2. ZHANG LiXiang1, XU TianMao3 & DONG HongKui4 1 Construction Engineering College, Kunming university of Science and Technology, Kunming 650051, china 2.School of Engineering, university of Aberdeen, Aberdeen AB2. 3UE, UK 3 Computing Center, Kunming university of Science and Technology, Kunming 650051, china 4 Hydraulic Energy department, Yunnan Electric Power Test and Research Institute, Kunming 6502.7, china 1. Construction Engineering College Kunming University of Science and Technology Kunming 650051 China2. School of Engineering University of Aberdeen Aberdeen AB24 3UE UK3. Computing Center Kunming University of Science and Technology Kunming 650051 China4. Hydraulic Energy Department Yunnan Electric Power Test and Research Institute Kunming 650217 China

This paper presents the result and analysis of the composition of energy loss occurring in the hydro turbine. Two new types of energy losses,namely the hydraulic loss in the flow channel and the impact loss,are defined. All losses within the hydro turbine are divided into four types and the loss coefficients are defined accordingly. Expressions or characteristic descriptions of these losses as well as the calibration method of the loss coefficients are presented. Furthermore,the torque model of the hydro turbine where the inner energy loss takes place is established. The developed model has been used to calculate the power loss due to the mechanical friction generated by the units’ rotation to solve the difficulty of measurements of the mechanical friction loss in the hydro turbine. The definition of the impact loss explains the phenomenon that the loss of no-load is greater than that of the rated operation. A set of conversion coefficients are defined using the characteristic parameters at the rated operation,which are used to transform the parameters in the torque model into those that are easily measured. Therefore,the expression of the hydro turbine power is converted into a function that has the main servomotor displacement as its single variable. This makes the proposed model be convenient to use. Finally,the proposed model and methods are calibrated and verified using the measured data of a hydropower plant. Good agreement between the modeled results and the measurements indicates that the proposed model can represent the inner energy loss characteristics of the hydro turbine.

关键词： hydraulic loss in flow channel impact loss loss coefficients conversion coefficients

DYNAMIC MECHANICAL BEHAVIOR OF Fe_3Al UNDER TENSILE IMPACT

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中国有色金属学会会刊：英文版 1999年第S1期9卷 138-141页

作者： Yanxiong Liu 1, Yuanming Xia 1, Mingwei Chen 2.and Dongliang Lin 2.1 department of Modern Mechanics, university of Science and Technology of{2., Hefei 2.002.,{2. 2.department of Materials Science, Shanghai Jiao Tong university, Shanghai 2.

The loading tests of Fe 3Al under tensile impact have been carried out by a self designed rotating circular disk tensile impact apparatus. An experimental study of Fe 3Al in the strain rate range from 80 s -1 to 1 2.0 s -1 was performed and the complete stress strain curves under tensile impact were obtained. On the basis of the experimental results, it is believed that Fe 3Al obviously exists dynamic ductility and effect of strain rate hardening. The yield strength, ultimate strength and failure strain increase with increasing strain rate. Based on the linear least squares fit, the relationship between the yield strength, ultimate strength, failure strain and strain rate under tensile impact was obtained. At the same time, one dimensional macro constitutive equation for Fe 3Al under tensile impact according to the elastic viscoplastic constitutive theory was derived.

关键词： Fe 3Al tensile impact dynamic ductility strain rate hardening

A case study: the investigation to nearshore submarine slides near Hujiu wharf of xiamen

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A case study: the investigation to nearshore submarine slide...