Mass-to-charge ratio refers to the molecular or atomic mass number and "z" to the charge number of the ion; however, the quantity of "m"/"z" is dimensionless by definition. An ion of 100 atomic mass units ("m" = 100) carrying two charges ("z" = 2) will be observed at "m"/"z" = 50. In the 19th century, the mass-to-charge ratios of some ions were measured by electrochemical methods. In 1897, the mass-to-charge ratio of the electron was first measured by J. J. Thomson. By doing this, he showed that the electron was in fact a particle with a mass and a charge, and that
Alan (given name) is today Russia, and who were known to Classical writers in the 1st century CE. According to historian Bernard Bachrach, the Alans settled in parts of what is today France, including Brittany, in the Early Middle Ages. Bachrach stated that the use of forms of the name in given names, surnames, and place names, are evidence of the continued influence of the Alans on the Gaulish, Breton and Frankish peoples. The Breton name "Alan" can not be a direct loan from the ethnic name of the Alans (rendered as "Alānī" or "Halānī" in Latin, from Scytho-Sarmatian "*Al[l]ān-", derived from Old