Hello Everyone, We have a Carlo Erba elemental analyzer attached to our mass spectrometer and are analyzing the d13C and d15N composition of organic samples. Over the past month we have had reaction columns (translucent silica type) cracking at an incredible rate. In one case the column cracked after only 20 samples. When we look at the column it is easy to see what is happening. It appears that the tin cups are eating into the column reducing the column wall to half its original thickness and thus weakening it. We are not running unusual samples or big samples and generally only use the thin-walled tin cups. However, when we use the thick-walled tin cups the columns seems to die faster. Has anyone else seen this problem? More importantly, does anyone know why it is happening and how I can solve it? Yours truly, Jennifer ------------------------------------------------------ Jennifer Mckay Agente de Recherche / Research Associate GEOTOP - Universite du Quebec a Montreal C.P. 8888, succursale Centre-Ville Montreal, Quebec, Canada H3C 3P8 Telephone bureau/office: 514-987-3000 (poste/ext 2413) Telephone lab: 514-987-3000 (poste/ext 7028) Telephone GEOTOP: 514-987-4080 Telecopieur/Fax: 514-987-3635 E-mail: [log in to unmask] or if that fails try [log in to unmask] ------------------------------------------------------