Аннотация

Infrared spectroscopy and scanning electron microscopy (SEM) studies were performed on the margins of a set of eighteen Estonian postage stamps dated between 1918 and 1924. SEM results showed the presence of Al, Si and Zn in the samples in different combinations. Two stamps contain kaolin and one ZnO. We could not find a clear relationship between the structure of the IR spectrum and the assumed geographical origin of the papers, but the need to accumulate a large set of results to use statistical methods is clear.

Линки и ресурсы

тэги