TORBAL toploading balance is fast, accurate and rugged. T O R B A L E T - 1 (160 g capacity, 1 m g accuracy) m a k e s accurate weighing easier a n d m o r e foolproof t h a n ever before. C o m p l e t e digital display without the use of optics or verniers — n o estimating. Substitution weighing with no knife edges or friction pivots m e a n s freedom f r o m m a i n t e n a n c e . " N u l l P r i n c i p l e " operation assures no effect o n accuracy because of sensitivity c h a n g e s as is the case with optical knife edge balances. Less affected by vibration t h a n optical knife edge b a l a n c e s . Z e r o p o i n t docs n o t c h a n g e with m i n o r c h a n g e s in t h e level of t h e E T - 1 . C o n v i n c e yourself— ask u s t o a r r a n g e a demonstration.
W R I T E FOR FREE BROCHURE,
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T H E T O R S I O N B A L A N C E C O . Clifton, New Jersey. Sales offices in Chicago, III.; San Mateo, Cal.; Montreal, Quebec; and Windsor, England. Balances manufactured in Waterford, Ireland and Clifton, New Jersey. CIRCLE 196 ON READER SERVICE CARD
TORBAL.
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Buying pH electrodes shouldn't be Chances are the last time you ordered pH electrodes you looked at the broken ones a n d ^ i just reordered the same old thing. Now there is a better way to go. Why should you spend valuable time poring over a bunch of catalogues ? At Micro Sensors, we've recog nized what a complicated mess it can be—different electrodes for different applica tions. As a result we have designed a line of pH electrodes that can
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Micro Sensors, Inc. 17401 Armstrong Avenue Santa Ana, C A 92705
CIRCLE 140 O N READER SERVICE CARD 706 A ·
ANALYTICAL
CHEMISTRY,
V O L . 4 5 , N O . 8, J U L Y
1973
(2) "Guidelines for B i o p h a r m a c e u t i c a l Studies in M a n , " ρ 17, A P h A Academy of P h a r m a c e u t i c a l Sciences, February 1972.. (3) J . R. Marvel, D. A. Schlichting, C. Denton, E . J . Levy, a n d M . M . C a h n , J. Invest. Dermatol, 42, 197 (1964). (4) A. J . Aguiar, J. Kic, J r . , A. W . Kinkel, a n d J . C. S a m y n , J. Pharm. Sci., 56, 847(1967). (5) H . J a c o b s o n a n d G. Reier, ibid., 58, 631(1969). (6) H . J a c o b s o n a n d I. Gibbs, p a p e r in p r e p a r a t i o n for J. Pharm. Sci. (7) "Analytical Profiles of Drug S u b s t a n c e s , " Vol I, K. Florey, E d . , Academ ic Press, N e w York, Ν . Υ., 1972. (8) T . Higuchi a n d E . B r o c k m a n n - H a n s sen, Pharm. Anal., Interscience (1961). (9) Anon., " T h e Stability a n d Stability T e s t i n g of P h a r m a c e u t i c a l s , a n Annotat ed B i b l i o g r a p h y , " 1939-1963 a n d 19641970, P h a r m a c e u t i c a l M a n u f a c t u r e r s (10) J. W . S u t h e r l a n d , D. E . Williamson, a n d J. E . Thervogt, Anal. Chem., 43, 206R(1971). (11) " N a t i o n a l F o r m u l a r y , " XIII, ρ 802, M e t h o d I, American P h a r m a c e u t i c a l Association, Washington, D.C., 1970. (12) Anon., Fed. Regist., 38, 885 (1973). (13) J . Koch-Weser, N. Engl. J. Med., 287, 227(1972). (14) W. Kalow, Rep. Ross Conf. Pediat. Res., 5 8 , 4 8 ( 1 9 6 8 ) . (15) R. G. Crounse, J. Invest. Dermatol., 37,529(1961). (16) K. E . Price, Z. Zolli, J r . , J . C. Atkin son, a n d H . G. L u t h e r , Antibiot. Che mother., 7 , 6 7 2 ( 1 9 5 7 ) . (17) G. J . M a n n e r i n g , "Selected Pharmacological T e s t i n g M e t h o d s , " Vol 3, M a r c e l Dekker, N e w York, N.Y., 1968. (18) A. H . Conney, Pharmacol. Rev., 19, 317(1967). (19) FDA Pap., ρ 5 ( J u n e 1971). Based on a talk given at the Eastern Analytical Symposium, Atlantic City, N.J., October 31November 2, 1972.
G l e n n A . B r e w e r is t h e a s s i s t a n t d i r e c t o r of a n a l y t i c a l r e s e a r c h of t h e S q u i b b I n s t i t u t e for M e d i c a l R e search. H e received his B S degree from H o b a r t College a n d M S a n d P h D d e g r e e s f r o m t h e U n i v e r s i t y of Wisconsin (biochemistry). As a senior research biochemist at Commercial Solvents Corp., he isolated a n d char acterized new antibiotic substances. D r . B r e w e r j o i n e d S q u i b b i n 1956 a n d s p e n t s e v e r a l y e a r s d e v e l o p i n g fer m e n t a t i o n p r o c e s s e s . I n 1960 h e joined the Analytical Research De p a r t m e n t as a research supervisor.
