【作者】 丁强；

【导师】 申晋；

【作者基本信息】 山东理工大学 ， 电力电子与电力传动， 2007， 硕士

【摘要】 具有表面效应、小尺寸效应和宏观量子隧道效应的亚微米及纳米颗粒表现出电、磁、光、声、热等方面的特性,在化工、医学、国防等领域被广泛应用,因而亚微米及纳米颗粒的测量具有重要的意义。目前,广泛使用的测量纳米颗粒的方法是光子相关光谱颗粒测量技术,该技术对实验条件要求较高、相应的测量仪器价格昂贵,一般用于研究领域。在亚微米及纳米材料制备行业,迫切需要一种低成本、测量方法简洁的快速颗粒测量方法。本文针对这一需求,进行了基于散射光信号分形的亚微米及纳米颗粒测量技术研究,主要研究工作如下:一、基于颗粒测量的光散射理论分析了颗粒散射光的波动特征,研究了颗粒散射光信号的分形表征。二、基于对测量装置结构参数的分析,研制了基于散射光信号分形的颗粒测量装置,并针对该测量方法对温度恒定性的特殊要求,研制了样品池温度控制器。三、分别在18、20、22、24、26、28、30℃温度下,对60、90、200、300、450nm标准聚苯乙烯颗粒进行了实验,计算了颗粒散射光信号的分形维数,研究了温度对分形维数的影响。研究结果表明,分形维数不但与颗粒粒径有关,而且与温度有关。颗粒粒径相同时,温度越高,分形维数越大。四、对不同温度下颗粒散射光信号的分形维数进行拟合,得到了在18℃到30℃(间隔0.1℃)温度下标准聚苯乙烯颗粒(粒径从50nm到480nm,间隔1nm)粒径与分形维数的对应关系。五、在26℃温度下,分别取采样点个数为512、1024、2048、4096、8192、16384、32768、65536,对60、90、200、300、450nm颗粒进行了测量。测量结果表明,当采样点数不小于16384时,颗粒测量结果的重复性和相对误差满足小于2%的要求。六、利用该测量方法,分别在18、20、22、24、26、28、30℃温度下,对60、90、200、300、450nm颗粒进行了实测,对测量结果的重复性和相对误差进行了分析,并就测量方法的特点与光子相关光谱颗粒测量方法进行了比较。与光子相关光谱颗粒测量技术相比,基于散射光信号分形的亚微米及纳米颗粒测量技术具有测量装置成本低、所需的采样数据量小、数据处理方法简洁且易于实现在线测量等优点。更多还原

【Abstract】 With the special characters in electrics, magnetic, photics and acoustics, submicron and nanometer particle has wide applications in many fields such as chemical, medicine, national defense, etc, so the measurement is very important. Currently, the Photon Correlation Spectroscopy (PCS) is the widely used measurement, but the equipment is expensive, and it is used in research generally. In the industry of the preparation of nanometer particle, the measurement is the urgent needed which is low-cost, simple and speeded. This dissertation studied on the measurement of submicron and nanometer particle based on the fractal of scattering light signal, the main researches are as following:1. Based on light scattering theory, the fluctuation of the scattered light was analyzed and the fractal characterization of the scattering light signal was investigated.2. Based on the analysis of structural parameters, a particle sizing apparatus was developed, and a temperature control device was designed to meet constant temperature requirement of the sample cell.3. Experiments with particles of different diameters were carried out under 18,20,22,24,26,28,30℃, the fractal dimensions of scattering light signal were computed, and the influences of temperature were researched. Conclusion can be obtained that the higher the temperature, the bigger the fractal dimensions for particles of the same diameter.4. The corresponding relationship of diameters from 50nm to 480nm and fractal dimension under temperatures from 18℃to 30℃was acquired.5. When the temperature was 26℃, particles with different diameters were measured with sampling points of 512,1024,2048,4096,8192,16384,32768,65536. And the results indicated that when the sampling points are more than 16384, the repeatability and relative error of the results were smaller than 2%.6. Particles with different diameters were measured when the temperature were 18、20、22、24、26、28、30℃, the repeatability and relative error of the results were analyzed. And finally this measuring method was compared with the PCS.Compared with PCS, the measurement which this dissertation studied is low-cost, its amount of sample data is small, the data processing method is simple, and it is easy to realize on-line measurement.更多还原