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金属陶瓷功能梯度热障涂层瞬态热负荷下的破坏分析

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兵工学报 2000年第1期21卷 42-45页

作者：王富耻王鲁吕广庶北京理工大学材料科学与工程系北京100081

本文采用试验分析和热弹性有限元方法研究了用等离子喷涂方法制备的ZrO2 NiCrAl系功能梯度热障涂层在瞬态热负荷下的破坏机理。

关键词：功能梯度材料热障涂层瞬态热应力有限元方法破坏机理 FAILURE OF METAL/CERAMIC functionally GRADIENT

Influence of Nanocrystalline Structure on Wear and Corrosion Behavior of Al-SiC<sub>P</sub>Composite

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Journal of Minerals and Materials Characterization and Engineering 2020年第2期8卷 47-58页

作者： Jagannati Venumurali Gaddam Bhanodaya Reddy Department of Mechanical Engineering College of Engineering Sri Venkateswara University Tirupati India

functionally graded (FG) Al-SiCP composites fabricated via centrifugal casting are widely used in automobile components particularly a brake rotor disc be-cause of its high SiC fraction at the outer periphery. However, when operated in corrosive environment like road deicing salts the disc is highly sensitive to the corrosion due to high SiC fraction. But, the nanocrystalline (NC) structured surfaces synthesized by severe plastic deformation (SPD) method have excel-lent wear and corrosion resistance at the surface. Therefore, shot peening (SP) as a SPD method conducted on one side of the stir casted FG Al composite having 10 wt% SiCP constant reinforcement in order to create NC structured surface. The SP treatment continued for 70 s and 140 s durations. Thereafter, the surface characteristics of the composite before and after SP were estimated by XRD and then the composites were tested by wear and corrosion tests. The results revealed that the SP for 140 s duration favors the induction of hardened layer, higher grain refinement (NC structure) and dislocation density which promotes the occurrence of high surface hardness, thus significantly improving its wear properties. However, higher dislocation density resulted from longer duration shown deterioration to the corrosion resistance. Whereas, the attained degree of NC structure is more pronounced over dislocation density resulted after 70 s SP duration, thereby composite showed excellent corrosion re-sistance. Thus, the composite with 70 s duration possessed excellent corrosion and relatively good wear properties too.

关键词： functionally Graded Al-SiCP Composite Shot Peening NC Structure Wear Corrosion

Numerical Solution for a FG Cylinder Problem Using Finite-Difference Method

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Applied Mathematics 2011年第1期2卷 123-130页

作者： Daoud S. Mashat 不详

A refined finite-difference approach is presented to solve the thermoelastic problem of functionally graded cylinders. Material properties of the present cylinder are assumed to be graded in the radial direction according to a power-law distribution in terms of the volume fractions of the metal and ceramic constituents. The governing second-order differential equations are derived from the motion and the heat-conduction equations. Numerical results for dimensionless temperature, radial displacement, mechanical stresses and electromagnetic stress are distributed along the radial directions. The effects of time parameter and the functionally graded coefficient are investigated.

关键词： functionally Graded Annular Cylinder Electro-Magneto-Thermoelastic Field

Hemodynamic Changes and Clinical Outcomes after the Intra/Extracardiac Fenestrated Fontan Procedure

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World Journal of Cardiovascular Surgery 2018年第2期8卷 29-39页

作者： Naveen Menon Chihyang Lin Cesar I. Mesia Achintya Moulick Randy Stevens Vicki Mahan Drexel University College of Medicine and Department of Pediatric Cardiothoracic Surgery St. Christopher’s Hospital for Children Philadelphia PA USA

Background: The primary concern of the Fontan procedure has been atrial arrhythmias, but little attention has been given to hemodynamic changes. This study’s purpose was to examine the hemodynamics and arrhythmias of the Intra/extracardiac fenestrated Fontan, and determine any advantages/disadvantages of this newer Fontan procedure. Methods: Patients undergoing the intra/ extracardiac fenestrated Fontan procedure at this institute between December 2009 and June 2017 were included in this retrospective evaluation of preoperative and postoperative hemodynamics during cardiac catheterization. End Diastolic Pressure (EDP), Pulmonary Artery Pressure (PAP), Left Atrial Pressure (LAP), and Transpulmonary Gradient (TPG) were the hemodynamic markers of interest. Occurrence of arrhythmias was also examined preoperatively, less than 2 weeks postoperatively, and greater than 2 weeks postoperatively. Morbidities and mortalities were also evaluated. Results: Fourteen patients underwent the procedure between December 2009 and June 2017. Preoperative data was available in all of these patients. Postoperative data was partially incomplete for atrial arrhythmias and hemodynamic data. EDP rose from 9.29 ± 3.50 mmHg to 10.33 ± 3.12 mmHg. PAP rose from 12.57 ± 2.50 mmHg to 14.27 mmHg. TPG dropped from 5.00 ± 2.29 mmHg to 3.25 ± 1.67 mmHg. LAP rose from 7.57 ± 2.87 mmHg to 10.30 ± 1.95 mmHg. Atrioventricular valve (AVV) regurgitation remained the same pre and postoperatively. 8 of 13 patients developed arrhythmias at less than 2 weeks postoperatively, and 5 of 12 patients developed arrhythmias at greater than 2 weeks postoperatively. There were no morbidities or mortalities. Conclusions: We found a statistically significant change in EDP, PAP, LAP, and TPG levels. It is unclear whether this is an advantage or disadvantage. The significance of these changes is unclear in this small population of patients. Further evaluation of hemodynamics, arrhythmias, morbidities and mortalities associa

关键词： Fontan functionally Univentricular Heart Circulatory Hemodynamics Hypoplastic Left Heart Syndrome Congenital Heart Disease (CHD)

Generalized Thermo Elasticity in an Infinite Nonhomogeneous Solid Having a Spherical Cavity Using DPL Model

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Applied Mathematics 2011年第5期2卷 625-632页

作者： Ahmed Elsayed Abouelrega 不详

The induced temperature, displacement, and stress fields in an infinite nonhomogeneous elastic medium having a spherical cavity are obtained in the context dual-phase-lag model. The surface of the cavity is stress free and is subjected to a thermal shock. The material is elastic and has an in?homogeneity in the radial direction. The type of non homogeneity is such that the elastic constants, thermal conductivity and density are propor?tional to the nth power of the radial distance. The solutions are obtained analytically employing the Laplace transform technique. The numerical inversion of the transforms is carried out using Fourier series expansions. The stresses, temperature and displacement are computed and presented graphically. A comparison of the results for different theories is presented.

关键词： Generalized Thermo Elasticity Nonhomogeneous functionally Graded Material (FGM) Laplace Transform Three-Phase-Lag Model

Vibration of Three-Layered FGM Cylindrical Shells with Middle Layer of Isotropic Material for Various Boundary Conditions

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World Journal of Mechanics 2014年第11期4卷 315-331页

作者： Muhammad Nawaz Naeem Awais Gul Khan Shahid Hussain Arshad Abdul Ghafar Shah Madiha Gamkhar Department of Mathematics G. C. University Faisalabad Faisalabad Pakistan Aerospace Research Institute and North-West Composites Centre University of Manchester Manchester UK Department of Mathematics Government Post Graduate College Jhang Jhang Pakistan Department of Statistics and Mathematics Agricultural University Faisalabad Faisalabad Pakistan

In the present study, vibration analysis of a three-layered cylindrical shell is performed whose inner and outer layers are composed of functionally graded materials whereas the middle one is assumed to be of isotropic material. This formation of a cylindrical shell influences stiffness modulii and the resultant material properties. The shell problem is formulated from the constitutive relations of stresses and strains with the displacement deformations and they are taken from Love’s thin shell theory. This problem is transformed into the integral form by evaluating the expressions for the strain and kinetic energies of the shell. Rayleigh-Ritz method is employed to solve the shell dynamic equations. Vibration characteristics of these cylindrical shells are investigated for a number of physical parameters and configurations of the fabrication of shells. The axial modal dependence is approximated by the characteristic beam functions that satisfy the boundary conditions. Results evaluated, show good agreement with the open literature.

关键词： functionally Graded Material Isotropic Material Three-Layered Cylindrical Shell Love’s Thin Shell Theory Rayleigh-Ritz Method Natural Frequency

COMPARISON OF MEMBRANE FLUIDITIES OF SEEDLING MITOCHONDRIA OF CHILLING-SENSITIVE RICE AND CHILLING-RESISTANT RICE

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Chinese Science Bulletin 1984年第2期29卷 244-247页

作者：杨福愉蔡同茂邢菁如陈文雯 Institute of Biophysics Academia Sinica Beijing

Miotchondria are relatively sensitive organelles, which can easily be changed both structurally and functionally by many environmental factors. Lyons et al. suggested there is correlation between the chilling-sensitivity of plant and the change in mitochondrial membrane after chilling treatment. We reported that the ultrastructure and oxidative phosphorylation efficiency of mitochondria isolated from the

关键词： mitochondria ultrastructure chilling fluidity functionally structurally oxidative Lyons labeled mannitol

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从文化转换角度谈动物成语的英译

龙岩学院学报 1990年第3期10卷 121-126页

作者：赖菲州

美国著名翻译理论家尤金·奈达曾十分精辟地论述过:What one must determineis the response of the receptor to the translated *** response musethen be compared with the way in which the original receptor presumablyreacted to the message when it was given in its original setting.(Eugene *** and Charles ***:Theory and Practice of Translation,Leiden:***,1969)(必须确定的是译文接受者对被译信息作出的反应,这种反应随后必须与原文接受者在原始背景中对此信息可能作出的反应方式进行比较。尤金·奈达与查尔斯·泰伯:《翻译理论与实践,1969年,自译。)他近年还进一步指出:The translator mustseek to employ a functionally equivalent set of forms which in so far aspossible will match the meaning of the originai source-language text.(Jande Warrd and Eugene ***:From One Languge to Another,Nashville.

关键词：文化转换译文接受者 translator translated 翻译理论文化特性意译法 functionally message 反应方式

无症状孤立性膀胱子宫内膜异位症误诊为膀胱肿瘤一例(英文)

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中华临床医师杂志（电子版） 2011年第21期5卷 6515-6517页

作者：卢扬柏湛海伦杨飞张泳欣黄杰夫周祥福 Department of Urolgy Affiliated Hospital of Sun Yat-Sen University Department of Radiology Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University

Introduction Endometriosis,defined as the presence of functionally active endometrial glands and stroma outside the uterine cavity and a benign condition,shares many malignancy biological behavior. The most common location is pelvic region,especially the ovaries and the broad ligaments. Occasionally the condition can involves urinary tract and the bladder is 84% of all urinary tract endometriosis,followed

关键词：膀胱肿瘤 endometriosis bladder malignancy pelvic urinary functionally 无症状 endometrial uterine