| Date | Text | |
|---|---|---|
12 Apr 1872
Georges Urbain |
birth Georges Urbain Born 12 Apr 1872; died 5 Nov 1938 at age 66. French chemist who first isolated lutetium, the last of the stable rare earths. Between 1895-1912 he worked on the rare earths and performed more than 200,000 fractional distillations in which he separated the elements samarium, europium, gadolinium, terbium, dysprosium and holmium. In 1907, he described a process by which Marignac's ytterbium (1879) could be separated into the two elements, ytterbium (neoytterbium) and lutetium. He named the new element after the Roman era village than stood on the site of Paris, his home town. (It was independently discovered by von Welsbach at about the same time.) Urbain also discovered the law of optimum phosphorescence of binary systems and wrote on isomorphism. |
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