Measurements of NO2 mixing ratios with topographic target light scattering-differential optical absorption spectroscopy system and comparisons to point monitoring technique

A topographic target light scattering-differential optical absorption spectroscopy(ToTaL-DOAS) system is developed for measuring average concentrations along a known optical path and studying surface-near distributions of atmospheric trace gases.The telescope of the ToTaL-DOAS system points to targets which are located at known distances from the measurement device and illuminated by sunlight.Average concentrations with high spatial resolution can be retrieved by receiving sunlight reflected from the targets.A filed measurement of NO2 concentration is performed with the ToTaL-DOAS system in Shijiazhuang in the autumn of 2011.The measurement data are compared with concentrations measured by the point monitoring technique at the same site.The results show that the ToTaL-DOAS system is sensitive to the variation of NO2 concentrations along the optical path.     

用扫描电镜测量纳米级标准长度的倾斜误差计算

用扫描电镜测量纳米级长度的时候[1, 2],被测长度的倾斜会导致被测长度产生误差,通常称其为倾斜误差.本文对于倾斜误差进行了实验和分析.给出了倾斜误差与倾斜角度的关系公式和对应数据表,同时提出了减小或消除倾斜误差的方法,为提高测量准确度,建立标准测量方法[3],创造了条件.     

3种常用超细颗粒粒径测试方法的比对研究

采用聚苯乙烯球形颗粒,对3种常用颗粒粒径测试仪器扫描电子显微镜（SEM）、原子力显微镜（AFM）、光子相关光谱仪（PCS）的测试结果进行比对,结果表明,对于球形颗粒,3种测试方法所得到的颗粒粒径具有一致性.