微波辐射淀粉热重实验及其数据的小波去噪处理

用频率为2 455 MHz的微波辐射0.5 g/mL的木薯淀粉乙醇悬浮液,使用热重-微分热重(TGA-DTG)测试手段对微波改性后的木薯淀粉的热特性进行表征,并采取小波变换去噪法与5点平均去噪法对TGA-DTG信号进行去噪处理研究。结果表明,小波变换去噪法在滤除淀粉TGA-DTG 信号噪声时优于5点平均去噪法；经小波去噪处理的TGA-DTG信号表明,随着微波辐射时间的增加,木薯淀粉热稳定性呈增加趋势。

Thermogravimetric experiments of the starch irradiated by microwave and wavelet denoising for its data

The ethanol suspension of cassava starch (0.5 g/mL) was treated by 2 455 MHz microwave irradiation. The thermal characteristics of the cassava starch being irradiated by microwave at different time were characterized by thermogravimetric analysis and differential thermogravimetric (TGA - DTG) testing method. TGA - DTG signal of cassava starch irradiated by microwave were researched in denoising by wavelet transform and 5 average method. The results show that wavelet transform is better than 5 average method in filtering out TGA - DTG noise signal of the starch. TGA - DTG wavelet denoising signal showed that with the increasing of microwave radiation time, the cassava starch the thermal stability increased.