线纹尺安装方式对空气折射率实时修正效果的影响

根据三种实际测量情况进行分析,介绍了在使用激光干涉法测量线纹尺过程中,空气折射率实时修正技术对测量结果的影响与仪器布局和线纹尺安装方式的关系,并得出了相应的结论.     

河北旅游资源深度挖掘:与文化、科技融合发展

旅游业只有与文化、科技融合发展,才能真正做大做强。本文借鉴兄弟省市推动旅游与文化、科技融合发展的成功经验,分析河北省旅游与文化、科技融合发展的现状,提出了推动河北省旅游与文化、科技融合发展的具体举措。     

投资项目评价系统的设计

介绍投资项目评价系统的设计思想与原则，阐述了该系统的模块设计及系统的主要功能。     

磁液悬浮式离心血泵实验研究

磁液悬浮式离心血泵是第三代人工辅助心脏系统的核心部件,血泵的好坏直接影响到整个系统的工作性能。本文针对一种新型磁液悬浮式离心血泵开展血泵性能测试的实验研究,通过设计实验系统测试获得血泵各项性能参数,并对此种新型血泵的综合性能进行评价,为新型磁液悬浮式离心血泵的研制工作提供实验依据。     

非均匀来流下三维激波反问题的微元密切轴对称解法

传统的密切轴对称理论被广泛应用于均匀来流下的三维密切曲面激波反设计，为解决非均匀来流条件下的三维曲面激波反问题，提出了一种微元密切轴对称流场（MOA）求解方法。该方法沿激波面的周向和流向构建一系列微元密切面，在每个微元面内进行三维向二维流动的等效转换，从而突破了传统密切方法中不能有横向波后流动的限制。利用该方法编写设计程序，分别基于带攻角来流条件和外锥型流来流条件重构了标准内锥曲面激波，并与数值仿真结果进行了比较。结果表明，非均匀来流下激波曲面的三维形状均与预设形状完全一致，实现了非均匀来流下曲面激波形状可控。MOA方法在吸气式高超声速推进领域中前体/进气道一体化设计方面有重要应用前景。     

喷雾液滴撞击液膜影响参数及流动机理分析

液滴撞击壁面是喷雾冷却中最常见的现象。使用计算流体力学软件中的Volume of Fluid （VOF）模型对液滴撞击壁面过程进行了数值模拟研究，研究了不同参数的液滴撞击壁面液膜过程的水花形态特点，针对水花高度和直径等参数进行了分析，通过运动间断理论和无量纲参数Re和We的变化分析了不同参数对液膜的流动特征和水花形态的影响及水花产生机理。结果表明：大液滴撞击液膜时能够改善液膜的流动状态；过大的液滴速度会产生大量飞溅及表面干涸；液滴撞击薄液膜时，液膜的流动性较好，当0.6<h*<1.2时，液膜的流动性不随液膜厚度改变。     

Ground-based and satellite DC-ULF electric field anomalies around Wenchuan M8.0 earthquake

The ground-based and satellite DC-ULF electric field data were analyzed around Wenchuan M8.0 earthquake on May 12, 2008 in China. The results show that ground electric field anomalies occurred at 3 stations located to the north and south of the epicenter with the amplitude of 3–100 mV/km. The change shapes and their amplitude of ground electric field anomalies are different largely due to their individual underground layer conductivity, water level and so on. The analysis of long time series illustrates that the abnormal geoelectric field started since March 2008. Onboard the DEMETER satellite, the ULF waveforms of electric field were collected and processed by wavelet transform method. The disturbances in the ionosphere were about 3–5 mV/m at a frequency band lower than 0.5 Hz. When the ground and space electric field anomalies were compared, their occurrence time and spatial distribution points are consistent with each other, including the long time anomalies from March 2008 and the short term ones 1–2 days before the Wenchuan earthquake. Finally, the coupling mechanism was discussed.