Microstructures of laser cladding of intermetallic-ceramic composite coatings

The microstructures of laser cladding of (Ni-24.5%(atom fraction)Al)+5O%(mass haction)WC coatingsbefore and after aging was comparetively studied by using SEM and TEM. It is shown that dissolving of WC and reprecipitating in the forms of WC and W,Coccurred during laser cladding, and intermetallic γ' (Ni3Al) orderly precipitatefrom metastable supersaturant Ni-matrix solid solution after heat treatment. The structures are favorable for coating'sproperties.     

激光三角法位移传感器测头设计

本文以直射式激光三角测头为例,导出了满足Scheimpfiag成象条件下的待测面位移与象位移间的准确关系,作为仪器结构参数设计的基础,并对提高测量精度和实用性的各项改进设计进行了分析。     

中空纤维膜无泡供氧过程的传质性能研究

使用中空纤维膜向液相系统中供氧时，无肉眼可见的气泡产生．与传统的泡式供氧相比，这种新颖的膜式无泡供氧具有传氧效率高、无泡沫产生和能耗低等优点，特别适宜应用于发酵、活性污泥废水处理和动物细胞培养等生物反应和人工控制的生命过程中．本文对中空纤维膜无泡供氧过程的传质机理、传质阻力、传质方程和影响传质系数的操作参数等传质性能进行深入探讨，并提出了“边界层压缩”模型，以解释在无泡供养中传质系数随压力变化的原因．     

纳焦飞秒激光在有机材料表面刻划微结构光栅的研究

使用振荡器产生的飞秒激光在透明有机材料PMMA表面进行了刻划微结构光栅的研究．通过理论分析得到了飞秒激光参数和平台移动速度对线宽的影响，进行了系统的加工实验，加工结果与理论分析基本吻合．在透明有机材料PMMA表面进行了多种光栅的刻划，并对刻划的光栅进行了衍射和色散测试，调整光栅的尺寸和排列方式，得到了形状各异的衍射图案。     

光纤温度传感器原理及应用

阐述了几种光纤温度传感器的概况和原理，重点介绍了双波长光纤温度传感器原理，并详细介绍了利用光纤测试温度的若干种方法．功能型光纤温度传感器是利用光纤的各种特性(相位、偏振、强度等)随温度变换的特点，进行温度测定．而传输型光纤温度传感器的光纤只是起到光信号传输的作用，以避开测温区域复杂的环境，最后通过对光纤温度传感器未来的发展趋势和特点，提出了一些看法。     

大豆/涤混纺纱混纺比及其不匀率的测试与计算方法

为了研究大豆蛋白纤维这种新型的纺织原料混纺比的测试方法,利用数理统计原理,采用密度梯度法对大豆/涤纶(65/35)混纺纱混纺比进行了测试和计算,该方法不仅可以得到混纺比均值,而且可以得到混纺比标准差,粗纱和细纱混纺比均值的控制范围分别为(63.64%,65.32%)和(64.16%,66.17%),粗纱和细纱混纺比标准差的控制限分别为2.89%和3.56%,同期细纱用溶解法实验结果为64.5%,2种方法误差为1.1%。     

浅析配电网馈线自动化智能监控模式

阐述了FA概念。具体介绍了目前在我国配电网自动化中采用的四种智能馈线自动化模式,并通过对实现方法、控制原理、应用效果等方面的分析讨论,总结出了这四种模式各自的控制特点。对四种智能馈线自动化模式中所采用的通信系统分通讯主干网和通讯规约两方面进行了详尽剖析。最后提出了实现配电网馈线自动化智能监控模式要解决的几个关键技术问题。     

Pulsed Laser Precision Length Measurements

The paper discusses mode locking use in pulsed lasers for precision measurement of large lengths.     

Emissivity Measurements on Metallic Surfaces with Various Degrees of Roughness: A Comparison of Laser Polarimetry and Integrating Sphere Reflectometry

Both integrating sphere reflectometry (ISR) as well as laser polarimetry have their advantages and limitations in their ability to determine the normal spectral emissivity of metallic samples. Laser polarimetry has been used for years to obtain normal spectral emissivity measurements on pulse-heated materials. The method is based on the Fresnel equations, which describe reflection and refraction at an ideally smooth interface between two isotropic media. However, polarimetry is frequently used with surfaces that clearly deviate from this ideal condition. Questions arise with respect to the applicability of the simple Fresnel equations to non-specular surfaces. On the other hand, reflectometry utilizing integrating spheres provides a measurement of the hemispherical spectral reflectance, from which the normal spectral emissivity can be derived. ISR provides data on spectral-normal-hemispherical reflectance and, hence, normal spectral emissivity for a variety of surfaces. However, the resulting errors are minimal when both the sample and the reference have a similar bidirectional reflectance distribution function (BRDF). In an effort to explore the limits of polarimetry in terms of surface roughness, room temperature measurements on the same samples with various degrees of roughness were performed using both ISR and a laser polarimeter. In this paper the two methods are briefly described and the results of the comparison are discussed.     

A review of modeling approaches for oriented semi-crystalline polymers

Modeling changes in the physical properties of oriented semi-crystalline polymer films is beneficial for understanding the fundamentals associated with structure property relationships and could be used for developing new polymer films with significantly enhanced physical properties. Relating the molecular changes observed in oriented polymer films to inherent polymer characteristics provides valuable insight for the development of new polymers which exhibit enhanced physical properties upon orientation. Modeling efforts will be reviewed that have attempted to use fiber composite theory to explain the transitions seen during the orientation process.