腮腺肿瘤:动态增强MRI加用扩散加权MRI能提高定性诊断的准确性吗?

目的 明确动态增强MRI加扩散加权成像（DWI）在鉴别腮腺良恶性肿瘤的价值。材料和方法 本项回顾性研究经机构委员会批准，免除知情同意。分析了47例病人50个病灶（36个良性、14个恶性）。所有病人都接受了扩散加权MRI和动态增强MRI。

Computational Analysis of a Variable Ejector Flow

现在的学习探讨能改进驱逐者效率并且在固定操作压力比率下面控制再通行比率的一个可变驱逐者。可变驱逐者是一台设备由改变驱逐者喉咙区域比率在给定的操作压力比率下面获得特定的再通行比率。数字模拟被执行在可变驱逐者内提供流动特征的理解。声音、超声的嘴在驱逐者系统，和活动的锥柱体作为主要的开车的嘴被采用，插入了到一个常规驱逐者弥漫的系统，被用来改变驱逐者喉咙区域比率。数字模拟基于可压缩的、平均 Reynolds 的海军司烧方程的一个充分含蓄的有限体积计划。结果证明可变驱逐者能在固定操作压力比率控制再通行比率。关键词可变驱逐者 - 驱逐者喉咙区域比率 - 再通行比率 CLC 数字

Flow Fields with Tip Leakage Vortex in a Small Axial Cooling Fan

为了改进扇子特征，特别效率和噪音，与一个大尖端清理一把小轴的冷却扇子铺平，有尖端漏旋涡的内部流动大小用一根我类型热电线的探针在扇子转子插头被执行。探查被设为向二个方向，平行和正常测试扇子的南方的飞机，并且二个方向性的速度部件被测量。从扇子测试的结果，测试扇子没在它的压力上与一个积极坡度有不稳定的特征，这被发现—流动率曲线。从速度测量的结果，尖端漏旋涡在最大的效率流动率和大流动率条件退出了，这被观察。然而，以小流动率条件，尖端漏旋涡没被观察，流动地被扩大向。

Computational Fluid Dynamics Benchmark of an Impulse Turbine with Fixed Guide Vanes

This paper presents the comparison of a three dimensional Computational Fluid Dynamics (CFD) analysis with empirical performance data of a 0.6 m impulse turbine with fixed guide vanes used for wave energy power conversion. Pro-Engineer, Gambit and Fluent 6 were used to create a 3-D model of the turbine. A hybrid meshing scheme was used with hexahedral cells in the near blade region and tetrahedral and pyramid cells in the rest of the domain. The turbine has a hub-to-tip ratio of 0.6 and results were obtained over a wide range of flow coefficients. The model yielded a maximum efficiency of approximately 54% as compared to a maximum efficiency of around 49% from experiment. A degree of insight into flow behaviour, not possible with experiment, was obtained.

Study of the Unsteady Condensation of Moist Air in Shock Tube

The major flow physics of the unsteady condensation in the subsonic flows induced by the unsteady expansion waves in shock tube was studied in this paper. The unsteady condensation phenomenon was analyzed by using the two-dimensional, unsteady, Navier-Stokes equations, which were fully coupled with a droplet growth equation. The third-order TVD MUSCL scheme was applied to solve the governing equation systems. The computational results were compared with the previous experimental data. The time-dependent behavior of unsteady condensation of moist air in shock tube was investigated in details. The results show that the major characteristics of the unsteady condensation phenomenon in shock tube are very different from those in the supersonic wind tunnels.

Features of Rotating Stall Cell in a Diagonal Flow Fan (in Case of Mid-loading Rotor)

旋转货摊房间的结构和行为试验性地在一把斜流动扇子被澄清。扇子特定速度是 1140 (r/min， m3/min， m ) ，并且在设计流动率的全部的压力上升系数是 0.345。外部 casing 墙上的静态的压力和在转子入口和插头的全部的压力用一个高反应压力变换器被测量。测量数据被 DPLA 技术，和结构的使用处理，旋转货摊房间的行为被获得。作为结果，货摊房间程度为环绕并且在货摊房间内的 spanwise 方向和压力分布被澄清。货摊房间繁殖的细节也被显示出。关键词斜流动扇子 - 旋转货摊房间 - 不稳定的流动 - DPLA 技术 CLC 数字 TH432.