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see protactiniumprotactinium
, radioactive chemical element; symbol Pa; at. no. 91; mass number of most stable isotope 231; m.p. greater than 1,600°C;; b.p. 4,026°C;; sp. gr. 15.37 (calculated); valence +4, +5. Protactinium is a malleable, shiny silver-gray radioactive metal.
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dissenting) (quoting 2 ANTHONY FITZHERBERT, NATURA BREVIUM 233B (9th ed.
64) In 1545, Henry Smyth and William Middleton both published Littleton's Tenures and Fitzherbert's Natura Brevium,(65) basic and widely-used books of legal reference.
A new papal college of scriptores brevium was created in 1503 (Partner, 1990, 12-16 and passim).