V O L U M E 2 4, NO. 1 1 , N O V E M B E R
1952
21 A
New Analytical Tools VERSATILITY · ACCURACY CONVENIENCEWSPEE^
Ά hew to turn an ion
LIGHT-SCATTERING MICROPHOTOMETER
into a nonentity
Measures directly, indicates, a n d records f r o m 2 0 micro-microlumens t o 2 0 lumens in f i v e d e c a d e r a n g e . Measures scattered light intensities a t angles f r o m 0 ° t o 1 4 7 ° ; o p t i c a l transmission f r o m 1 0 ~ 9 % t o 1 0 0 % ; o p t i c a l density from 0 to 1 1 ; d e p o l a r i z a t i o n ; dissymmetry; absolute t u r b i d i t y ; d r o p l e t size a n d concent r a t i o n ; purity o f colloids; r a t e a n d change o f molecular size; particle size a n d concentration; r a t e a n d evaluation o f a n t i g e n - a n t i b o d y reactions; micro-fluorescence; specular a n d diffuse light reflectance; enucleation; p r e c i p i t a t i o n ; flocculation; crystallization; molecular w e i g h t ; scintillation efficiency, etc. BULLETIN
2202-B
PHOTOMULTIPLIER MICROPHOTOMETER For precise measurement a n d comparison o f light intensities, a t selected wave-lengths, from 2 0 micro-microlumens to 2 0 lumens, densities f r o m 0 to 1 1 , a n d p h o t o t u b e current f r o m 1 0 - 5 t o 1 0 - 1 1 amperes. Range can b e e x t e n d e d with neutral filters. Useful f o r f i l m densitometry;colorime t r y ; t u r b i d i m e t r y ; fluorimetry; light scattering; scintillation efficiency o f phosphors; specular a n d diffuse r e flectivity; o p a c i t y ; glossîmetry; luminescence; etc. Direct r e a d i n g — indicates per cent transmission, density, a n d photocurrent microamperes covering 5 decades without correction factors. Has outlet f o r connection to a recorder. Accommodates r e a d i l y a v a i l a b l e 2-in square filters, either single or in combinations up to Vs in. thick, also many other o p t i c a l accessories. A-c. o p e r a t e d a n d s t a b i l i z e d . W e i g h s only 1 1 l b . BULLETIN
2190-B
HIGH-SPEED ANGLE CENTRIFUGE A r e l i a b l e , s a f e , a n d modern highs p e e d centrifuge with unique balancing mechanism that assures g r e a t e r s p e e d a n d s a f e t y . R.F.C. d e v e l o p e d : 2 5 , 0 0 0 g a t full s p e e d o f 1 4 , 0 0 0 r.p.m. Tube a n g l e , 3 2 degrees. Readily i n t e r c h a n g e a b l e , self-balancing, s t a n d a r d i z e d precision-machined rotors (maximum c a p a c i t y , 4 0 0 ml.), also a v a r i e t y o f tubes a n d a d a p t e r s a r e a v a i l a b l e f o r maximum f l e x i b i l i t y . Integral control p a n e l a n d g u a r d . Minimum servicing; low-cost maintenance. S e l f - a l i g n i n g mechanism reduces convection currents in the tubes to a minimum. Easily s t e r i l i z e d . No n e e d f o r f r e q u e n t lubrication. Fullya d j u s t a b l e s p e e d control. Self-contained unit construction. Can b e used in refrigerators. BULLETIN
52-134-B
A M E R I C A N INSTRUMENT C O M P A N Y , I N C . Silver Spring, Maryland · In Metropolitan Washington, D. C.
CHEMISTRY OF CHELATION To turn "somebody" into "nobody" you remove him from his environment and prevent him from exerting further influence on it. Essentially, this is what you do when you use Versene* and the Chemistry of Chelation to make metallic ions lose theft chemical identities. When metal ions form a complex compound with Versene, they be come so strongly attached to the Versene that they lose their identity and can no longer interfere with or influence their environment in any way. V CHELATION IS THE KEY In other words, Chelation and the Versenes* (powerful Chelating Agents) may well be the solution to your chemical problem — especially if it involves metallic ion contamination in any kind of liquid formulation. GUARANTEED QUALITY Made only under processes originated, developed and patented by F. C. Bersworth, the Versenes* are ex ceptionally stable at elevated temperatures and all pH*s. Quality standards of manufacture are so high that uni form complexing power is guaranteed in both sample and carload quantities. Find out now how these most powerful Chelating Agents can help you. Write Dept. V for Technical Bulletin #2 and samples. Chemical counsel available. 'Trade Mark
Registered.
V E R S E N E W A T E R TEST KIT. Tells t o t a l hardness in 2 m i n u t e s . A c c u r a t e t o I g r a i n p e r g a l . C o m p l e t e w i t h i n s t r u c t i o n s $5.00 p o s t p a i d .
fc*
BERSWORTH CHEMICAL CO. FRAMINGHAM, MASSACHUSETTS WAREHOUSE STOCKS Providence Agent: George Mann & Co., Inc., 251 Fox Point Boulevard, Providence, R. I. W. Coast Agent: Griffin Chemical Co., San Francisco, Los Angeles Midwest Agent: Kraft Chemical Co., Inc., 917 W. 1 8th Street, Chicago Wasatch Chemical Co., Salt Lake City, Utah Southwest Agents: Barada & Page, Inc., Dallas, Houston, Kansas City, etc. Chas S. Tanner Co., 1815 Liberty Life Bldg., Charlotte, North Carolina
