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An i n t e r f a c e d e v i c e c o n s i s t i n g o f sampling v a lve, dispenser, t i m i n g c i r c u i t , and c o a n a l y t e a d d it i o n i s d e s c r i b e d . The l i q u i d chromatograph e l u e n t i s dispensed ( 3 7~~) t o t h e g r a p h i t e f u r n a c e o f an H i t a c h i 170-70 Zeeman e f f e c t atomic a b s o r p t i o n spect r o m e t e r which serves as an element s p e c i f i c d e t e ct o r . The a d d i t i o n o f c o a n a l y t e reduces t h e v o l a t i l -1075 1076 VICKREY, BLJREN, AND HOWELL i t y f o r nonmetals and increases t h e s e n s i t i v i t y f o r these elements a t low c o n c e n t r a t i o n . The i n t e r f a c e i s c o n t r o l l e d by a t i m i n g c i r c u i t comprised o f 555 t i m e r i n t e r g r a t e d c i r c u i t s and a l l o w s automated s i ng l e element a n a l y s i s o f t h e e l u e n t w i t h a n a l y s i s r e p e t i t i o n r a t e o f approximately one p e r minute. The r e s u l t s u s i n g t h i s i n t e r f a c e f o r t h e m o n i t o r i n g o f t h e s e p a r a t i o n o f several selenium c o n t a i n i n g compounds ( u s i n g N i 2 + as coanalyte) i s discussed.

The coating of the graphite furnace surface with refractory metal salts Increases the atomization efficiency of tin. The use of zlrconyl acetate Improves the atomization of tin, selenium, and arsenic. The treated surface shows granules containing zirconium. The zirconium concentration on the Inside of the tube decreases with Increasing atomizations. The uniformity of the zirconium-treated surface is compared to treatment with sodium salts of molybdate and tungstate.