亚洲一区欧美在线,日韩欧美视频免费观看,色戒的三场床戏分别是在几段,欧美日韩国产在线人成

In order to find a method of vinegar detection based on ultraviolet fingerprint technology, different vinegars were used as materials, evaporation and ultraviolet spectra were studied to investigate how the factors of wavelength, dilution ratio of the liquid, evaporation temperature and mass concentration of reference affect ultraviolet vinegar curves. Finally the experiment conditions of the method were determined: wavelength at 245～330nm, quantity dilution ratio of the liquid at 1∶6,evaporation temperature at 45℃, mass concentration of reference at 45g/L. Similarity was used as the indicator to evaluate the ultraviolet curves’ feature of reproducibility, stability and difference. Three replicates of each measurement the result show that the similarity among vinegar samples fingerprints was more than 0.90, the similarity of the fingerprint of each vinegar samples in different depositing time was more than 0.90, the similarity of different fingerprint of different vinegar samples was less than 0.90. The method with excellent repeativeness, stability and differentiae.