利用掃描式電子顯微鏡及能譜儀探討乾燥金針表面沉積物之化學變化   全文下載

Application of Scanning Electron Microscopy-Energy Dispersive X- Ray Spectrometer to Characterize the Chemical Composition of Deposits on the Surface of Dried Day Lily

利用掃描式電子顯微鏡及能譜儀（SEM-EDS）可快速篩選二氧化硫殘留量過高之市售乾燥金針。實驗結果發現超過3 亞硫酸納處理，或亞硫酸納浸漬後未經漂水之金針樣品，經乾燥後在掃描式電子顯微鏡下，金針表面可觀察到顆粒狀沉澱物，以X-ray元素分析證實沉澱物為亞硫酸鈉。將無沉澱物之金針樣品其SEM-EDS所測得之硫／碳值，與改良式Monier-Williams法測得之二氧化硫量作線性回歸，發現此兩種測定方法有良好之相關性（R2 = 0.8994）。

An innovative and simplified method to characterize the chemical composition of the residual sulphite deposits on dried day lily using scanning electron microscopy- energy dispersive X-ray spectrometer (SEM-EDS) was developed in this study. Granular deposits were observed by SEM on the surface of dried day lily overdosed with sulphiting agents. Laboratory scale model studies showed that soaking in 3% sodium bisulphite without subsequent washing may lead to the accumulation and precipitation of sodium bisulphite crystals. EDS analysis indicated that these deposits are sodium bisulphite. A strong correlation (R2 = 0.8994) was obtained between Sulfur/Carbon ratio calculated from SEM-EDS data and sulfur dioxide concentration determined by modified Monier-Williams method in day lily samples without crystals on the surface. 利用掃描式電子顯微鏡及能譜儀（SEM-EDS）可快速篩選二氧化硫殘留量過高之市售乾燥金針。實驗結果發現超過3 亞硫酸納處理，或亞硫酸納浸漬後未經漂水之金針樣品，經乾燥後在掃描式電子顯微鏡下，金針表面可觀察到顆粒狀沉澱物，以X-ray元素分析證實沉澱物為亞硫酸鈉。將無沉澱物之金針樣品其SEM-EDS所測得之硫／碳值，與改良式Monier-Williams法測得之二氧化硫量作線性回歸，發現此兩種測定方法有良好之相關性（R2 = 0.8994）。