Supplier Page from Thermo Fisher Scientific for Niobium slug, 3.175mm (0.125in) dia x 6.35mm (0.25in) length, 99.95% (metals basis excluding Ta)
Ellagic acid, 97% from Thermo Fisher Scientific
Ethyl 3-aminocrotonate, 98.5% from Thermo Fisher Scientific
Ethyl cyanoformate, 99% from Thermo Fisher Scientific
Fluorescein, pure from Thermo Fisher Scientific