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Influence of Alumina Addition on the Optical Property of Zirconia/Alumina Composite Dental Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2011年第4期26卷 690-695页

作者：蒋丽李伟 State Key Laboratory of Oral Diseases Sichuan University

The influence of various alumina additions on the optical property of zirconia/alumina composite ceramics was investigated. The relative sintered densities, transmittances, color and the microstructure of the composite ceramics were studied. The experimental results showed that the relative sintered densities and transmittances decreased with alumina addition. The lightness increased obviously but the chroma change was small. Pure zirconia nanopowders sintered densely could obtain the relatively high transmittance, while the transmittance and the lightness of slight addition changed significantly. The zirconia/alumina composite ceramics with alumina addition less than 7.5wt% could achieve the relatively stable and reliable optical properties.

关键词： alumina addition zirconia/alumina ceramics transmittance color optical properties

Cholinergic anti-inflammatory pathway： a possible approach to protect against myocardial ischemia reperfusion injury

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Chinese Medical Journal 2010年第19期123卷 2720-2726页

作者： XIONG Jun XUE Fu-shan YUAN Yu-jing WANG Qiang liao Xu WANG wei-li Department of Anesthesiology Plastic Surgery Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100144 China

Objective A general review was made of studies involving：（1） the concept and mechanism of the cholinergic anti-inflammatory pathway （CAP）, （2） the important role of inflammatory response in myocardial ischemia reperfusion （I/R） injury and （3） the evidence and mechanisms by which CAP may provide protection against myocardial I/R injury. Data sources The data used in this review were mainly from manuscripts listed in PubMed that were published in English from 1987 to 2009. The search terms were ＂vagal nerve stimulation＂, ＂myocardial ischemia reperfusion injury＂, ＂nicotine acetylcholine receptor＂ and ＂inflammation＂. Study selection （1） Clinical and experimental evidence that the inflammatory response induced by reperfusion enhances myocardial I/R injury. （2） Clinical and laboratory evidence that the CAP inhibits the inflammation and provides protection against myocardial I/R injury. Results The myocardial I/R injury is really an inflammatory process characterized by recruitment of neutrophils into the ischemic myocardium and excessive production of pro-inflammatory cytokines. Because the CAP can modulate the inflammatory response by decreasing the production and release of pro-inflammatory cytokines, it can provide protection against myocardial I/R injury. Conclusions The CAP can inhibit the inflammatory response induced by reperfusion and protect against myocardial I/R injury. It represents an exciting opportunity to develop new and novel therapeutics to attenuate the myocardial I/R injury.

关键词： vagal nerve stimulation myocardial ischemia reperfusion injury nicotine acetylcholine receptor cytokines inflammation

NUMERICAL SIMULATION AND EXPERIMENTAL INVESTIGATION OF THE GUIDE-VANE FLOW AND THE INFLUENCE FROM THE LEAKAGE FLOW

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Journal of Hydrodynamics 2003年第1期15卷 103-110页

作者： liaowei-li liJian-zhong InstituteofwaterResourcesandHydroelectricEngineering Xi＇anUniversityofTechnologyXi＇an710048China InstituteofwaterResourcesandHydroelectricEngineering Xi＇anUniversityofTechnologyXi＇an710048China

This paper presents numerical and experimental results of the flow in the tipclearance region of the guide vane row in hydraulic turbine. The 3-D Navier-Stokes equations wereemployed to model the flow in end clearance region of guide vane cascade, the Reynolds stressdifferential model was used for turbulence closure, and the body-fitted curvilinear coordinates andthe SIMPLE! algorithm were adopted. The governing equations were discretized with the non-staggeredgrids by means of the finite volume method. Detailed comparison of hydrodynamical characteristics ofguide vane in hydraulic turbine with or without tip gap was made. Special attention was paid to theinfluence of leakage flow on the main flow and to the movement of tip leakage flow in the end guidevane. The position and strength of the roll-vortex on the sides of guide vane in were *** numerical solutions agree with the experimental results obtained by particle image *** results help to clarify the loss, wear and cavi-tation erosion between the guide vane andrings, especially for those used in the Yellow River which has a high sediment content.

关键词： leakage flow guide vane reynolds stress differential model

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稀疏气泡流动的粒子跟踪测速技术研究

水利学报 2005年第7期36卷 825-829页

作者：许联锋廖伟丽陈刚李建中西安理工大学水利水电学院陕西西安710048

采用动态阈值技术实现了对气泡图像的正确分割,利用灰度加权方法提高了气泡颗粒的定位精度。根据稀疏气泡流动图像的特点,提出了一种新的基于相关的粒子跟踪测速算法(2HPTV)。通过进行两时刻中围绕待研究气泡所取的两个小的诊断窗口的... 详细信息

采用动态阈值技术实现了对气泡图像的正确分割,利用灰度加权方法提高了气泡颗粒的定位精度。根据稀疏气泡流动图像的特点,提出了一种新的基于相关的粒子跟踪测速算法(2HPTV)。通过进行两时刻中围绕待研究气泡所取的两个小的诊断窗口的相关运算,成功实现了气泡颗粒的轨迹追踪。实验表明本文算法较传统的PIV技术在测速精度上有很大程度的提高,与4帧粒子跟踪测速算法相比,降低了对摄像机帧频的要求,具有较强的实用性。

关键词：稀疏气泡流图像处理粒子跟踪测速动态阈值技术灰度加权法

Intermediate Temperature Sintering of La-Modified Ph(Zn_(1/3)Nb_(2/3))O_3-PbZrO_3-PbTiO_3 Piezoelectric Ceramics

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Journal of Materials Science & Technology 2001年第2期17卷 287-289页

作者： Xiangping JIANG, Jun liao, Xiaoyong wei, Guorong li, Daren CHEN and Qingrui YIN Laboratory of Functional Inorganic Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China

in order to realize the co-firing with Ag/Pd electrodes in multilayer devices, Pb(Zn1/3Nb2/3)(1-x-y) ZrxTiyO3(0.25 详细信息

in order to realize the co-firing with Ag/Pd electrodes in multilayer devices, Pb(Zn1/3Nb2/3)(1-x-y) ZrxTiyO3(0.25line grains in ceramics were well grown. d(33) of manufactured sample was as high as 560 x 10(-12)C/N. k(p) was about 0.61 and tg delta about 30 x 10(-3). The existence of liquid phase examined by electron diffraction in PZN-PZT sample is beneficial to sintering of the ceramic.

关键词： O3-PbZrO3-PbTiO3 Piezoelectric Ceramics Nb PZT La Zn

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考虑流固耦合的轴流式叶片强度分析

河海大学学报（自然科学版） 2009年第4期37卷 441-445页

作者：商威廖伟丽郑小波西安理工大学水利水电学院陕西西安710048

以轴流式水轮机全流道三维湍流数值计算结果为基础,分析水轮机的压力脉动;采用弹性力学非稳态有限元法分析轴流式叶片的强度;利用弱耦合技术,对固体域和流体域进行顺序迭代,并进行了水轮机的流固耦合分析.结果表明,在水压力作用下,叶片... 详细信息

以轴流式水轮机全流道三维湍流数值计算结果为基础,分析水轮机的压力脉动;采用弹性力学非稳态有限元法分析轴流式叶片的强度;利用弱耦合技术,对固体域和流体域进行顺序迭代,并进行了水轮机的流固耦合分析.结果表明,在水压力作用下,叶片变形的最大位移发生在叶片出水边靠近叶片外缘处,最大应力出现在叶片上端面和法兰相接处,叶片变形对压力脉动的幅值影响明显.

关键词：轴流式叶片非定常有限元弱耦合强度

穿越城镇发达地区高速公路的路线方案探讨——以莞番高速为例

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广东交通职业技术学院学报 2022年第2期21卷 30-35页

作者：廖利伟中交第一公路勘察设计研究院有限公司深圳分院广东深圳518049

以莞番高速公路穿越城镇区域路线方案选择为例,从城市发展和规划、工程规模、拆迁量及外部影响等角度对路线方案进行设计和比选,为最优方案的最终选择提供真实可靠的依据。通过工程实例,总结出高速公路与城市发展规划之间相互促进及相... 详细信息

以莞番高速公路穿越城镇区域路线方案选择为例,从城市发展和规划、工程规模、拆迁量及外部影响等角度对路线方案进行设计和比选,为最优方案的最终选择提供真实可靠的依据。通过工程实例,总结出高速公路与城市发展规划之间相互促进及相互制约的关系,结合城市的空间现状和规划,选择最优的高速公路穿越方案。

关键词：高速公路城市空间路线方案设计

水轮机主轴中心孔补气对尾水管内部流态的影响

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水利学报 2008年第8期39卷 1005-1011页

作者：廖伟丽姬晋廷逯鹏罗兴锜西安理工大学水利水电学院陕西西安710048

基于水气两相流模型,研究了水轮机主轴中心孔补气对尾水管涡带的影响以及对于改善水轮机内部流态的作用。研究表明,不同工况下最优补气量的大小有一定的差异;由于气体能量较小,补气量过小,在转轮的影响下它很快稀释于水体中,进入尾水管... 详细信息

基于水气两相流模型,研究了水轮机主轴中心孔补气对尾水管涡带的影响以及对于改善水轮机内部流态的作用。研究表明,不同工况下最优补气量的大小有一定的差异;由于气体能量较小,补气量过小,在转轮的影响下它很快稀释于水体中,进入尾水管直锥段中心涡带区域的气体很少,起不到改善水流的作用,补气量过大,又会使断面过水面积减小,尾水管直锥段横向水流增强导致不利流态。研究成果揭示了补气量的大小对于改善尾水管内部水流的影响,从而为寻找最优的补气量提供理论依据。

关键词：尾水管补气最优补气量两相流

高速公路互通立交方案的设计--以大岭山互通为例

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广东交通职业技术学院学报 2021年第3期20卷 4-7页

作者：廖利伟中交第一公路勘察设计研究院有限公司深圳分院广东深圳518049

本文以莞番高速公路大岭山互通立交为例,从交通量、工程规模、拆迁量及外部影响等角度对立交方案进行设计和比选,为立交最优方案的最终选择提供真实可靠的依据。通过工程实例,总结出立交节点设计最重要的三个步骤:根据交通需求和控制因... 详细信息

本文以莞番高速公路大岭山互通立交为例,从交通量、工程规模、拆迁量及外部影响等角度对立交方案进行设计和比选,为立交最优方案的最终选择提供真实可靠的依据。通过工程实例,总结出立交节点设计最重要的三个步骤:根据交通需求和控制因素确定立交方案的基本型式,针对不同控制因素及地方诉求进行多方案研究,对所有方案进行综合比选分析并确定推荐方案。

关键词：高速公路大岭山立交方案设计