排序方式: 共有110条查询结果,搜索用时 31 毫秒
101.
An analysis of the instability in the Taylor-Couette flow of fiber suspensions with respect to the non-axisymmetric disturbances was performed. The constitutive model proposed by Ericksen was used to represent the role of fiber additives on the stress tensor. The generalized eigenvalue equation governing the hydrodynamic stability of the system was solved using a direct numerical procedure. The results showed that the fiber additives can suppress the instability of the flow. At the same time, the non-axisymmetric disturbance is the preferred mode that makes the fiber suspensions unstable when the ratio of the angular velocity of the outer cylinder to that of the inner cylinder is a large negative number. 相似文献
102.
分析光纤光栅传感机理,阐述可调光纤F-P滤波器的工作机理和特点,并基于单片机AT89C52实现光纤光栅解调系统。 相似文献
103.
104.
本实验研究了以不锈钢片单独做阳极和以活性碳纤维毡片(+不锈钢)的复合阳极对TNT废水电解效果的影响,并对电解机理进行了初步的探讨。原废水的TNT浓度为70—90mg/L,COD约为290—340mg/L,PH为7.5—9。实验数据显示,当槽电压为10V,PH值为3,外加电解质Na2SO4lg/L,极板间距为4era,电流密度为15mA/em。,搅拌转速为260r/min,电解2h时,以活性碳纤维+不锈钢复合材料为阳极处理原废水,对TNT和COD的降解率分别为66.6%和55.5%,然而单独以不锈钢材料为阳极情况下,对TNT和COD的降解率仅为43.5%和24.7%。结果表明以活性碳纤维+不锈钢复合材料为阳极对TNT废水中的有机物的电解效果显著,对实际工程废水处理有一定的指导意义。 相似文献
105.
光纤感测温预警系统是较不常见的消防探测系统,电厂消防是典型的工程,本文将两者结合形成一个典型设计。 相似文献
106.
本文将钢尺作为一反射光栅的模型,较精确地、简便地"量"出氦氖激光的波长。并将实验结果与He-Ne激光的标准波长进行了比较,得出该方法具有较高的精确度,这是一种简便易行的测量激光波长的方法。 相似文献
107.
用稳相积分法分析了点光源经光栅光阑的衍射,得知加光阑对光栅的衍射虚像点的位置没有影响。将全息图置于有限大小平面透射光栅的衍射区域,并且满足全息图成消色散再现像条件时,白光中所有波长的色光都参与再现,形成白光消色散再现像。在有限大小平面透射光栅的衍射面上白光区域以外的区域将形成色光区域分布,将全息图置于该区域时,全息图再现像将呈现彩色。 相似文献
108.
分析光纤光栅传感机理,阐述可调光纤F-P滤波器的工作机理和特点,并基于单片机AT89C52实现光纤光栅解调系统。 相似文献
109.
A discrimination measurement method and demodulation technique for fiber Bragg grating (FBG) sensors were presented using digital filtering technique. The system can control a tunable fiber Fabry-Perot filter with sawtooth wave voltage generated by digital clock to interrogate FBG sensors. Using the analogue digital converter (ADC), the reflected FBG signals were sampled with synchronous digital clock. With the aid of digital matched filtering technique, the sampled FBG signals were processed to obtain the maximum signal-to-noise ratio (SNR) and the Bragg wavelength shift from the FBG signals was recovered. The results demonstrate that this system has a scanning range of 1 520 nm-1 575 nm,and the wavelength detection accuracy is less than 2 pm with 1.5 Hz scanning frequency. 相似文献
110.
普通光学显微镜只能传递光波的振幅信息而丢失相位信息,因此用普通光学显微镜对透明和半透明的物体观察会丢失一些特征信息。植物纤维基本介于透明体与半透明体的状态,而透明物体对光只产生相位的移动而不能显著地改变光的振幅,所以在普通光学显微镜中难以观察到棉麻纤维的局部细节特征信息。而微分干涉相衬显微镜所观察的物体是位相物体,因此应用微分干涉显微镜可以明显改善这种情况。 相似文献