No. 450 Gas Stream Purifier T h e model 4 5 0 purifier w i t h model 4 5 4 replaceable cartridge is specially designed f o r c o n t r o l l i n g the acetone vapor in acetylene. T h e cartridge contains activated charcoal. It be longs in an A A system. Circle 1 4 4
Automatic Regulators 1PA-510and 1 L 3 2 6 If y o u are using A A , choose the cor rect regulators. In the l a b o r a t o r y , use regulators designed f o r the specific gas. I n f o r m a t i o n on these regulators can be o b t a i n e d . Circle 1 4 7
Cylinder Scale, Model S510
Series 6103 Flash Arrestor
T o judge accurately when a lique fied gas is nearing e m p t y , Matheson has designed and sells a cylinder scale. We recommend this f o r nitrous oxide because it w i l l let y o u k n o w ... and it's the o n l y way ... when the c y l inder is e m p t y . Invaluablel Circle 1 4 5
A flash arrestor is installed as a part of the A A system d o w n s t r e a m , af ter the regulator and cylinder. Some instruments have a b u i l t - i n flash arrestor. If y o u r s does n o t , t w o should be installed. Acetylene is highly flammable. S h o u l d flashback occur, w i t h the accompanying shock wave, this device w i l l instantly seal o f f the path t o b o t h regulator and cylinder ... preventing an explosion of m u c h greater magnitude in either regulator or c y l i n d e r , b o t h of w h i c h contain more gas. Flash arrestors are recommended f o r b o t h fuel gas and oxidizer gas lines. For more i n f o r m a t i o n , circle 1 4 8
Improved Operation Of An Atomic Absorption Spectro photometer Chemical analysis by atomic absorption spec troscopy is achieved by converting the sample into an atomic vapor and measuring its absorbance at a selected wavelength. The measured absorbance is proportional to concentration. The analysis is made by comparing this absor bance with a reference sample of known com position under similar conditions. Atomic absorption lines are so narrow that the use of a conventional monochromator is impractical to measure them. Commercial in struments overcome this by the use of hollow cathode lamps which emit atomic spectral lines of the element to be determined.
Nitrous Oxide Heater Because nitrous o x i d e , f r e q u e n t l y used as an oxidizer gas in A A , is l i q uefied gas, or a gas over l i q u i d in a cylinder, it o f t e n cools or ices on expansion, causing problems in a u t o m a t i c c o n t r o l . The heater we offer is installed between cylinder and regulator and eliminates icing and allows for higher flows. T h e r m o statically c o n t r o l l e d , the N „ 0 is not overheated and the operator can con centrate on his i n s t r u m e n t . Works simply w i t h 115 V A C . Circle 1 4 6
Acetylene 99.6% and Nitrous Oxide 99.0% These are pure gases containing less impurities than commercial grades. We recommend t h e m and specially p u r i f y t h e m f o r A A instrument use. The purer the gas, the less interfer ence in final results. Circle 1 4 9
Elements are measured after they have been put into solution either aqueous or organic. The so lution is then sprayed into a flame, generally, air-acetylene. Some compounds, like the rare earths, require a highly reducing flame. This is done most safely by burning the acetylene in nitrous oxide which gives more available oxy gen than air. For years Matheson has been servicing scientists using AA spectroscopy, not only with gases but with other equipment which makes opera tion easier, and more important, safer. These items are at left. If you're not familiar with them we will be delighted to rush literature to you.
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atheson
Lyndhurst, N.J. 07071 East Rutherford. NJ 0 7 0 7 3 Morrow. Georgia 3 0 2 6 0 Bridgeport. NJ 08014 Gloucester. Massachusetts 01930 Joliet, Illinois 6 0 4 3 4 Dayton. O h i o 4 5 4 2 4 La Porte. Texas 77571 C u c a m o n g a . California 91730
Newark. California 9 4 5 6 0 Dorsey. Maryland 21227 Gonzales, Louisiana 7 0 7 3 7 Whitby. Ontario. Canada L I N 5R9 E d m o n t o n . Alberta, Canada T 5 B 4K6 Β 2431 Oevel, Belgium 6 0 5 6 H e u s e n s l a m m . West Germany
ANALYTICAL CHEMISTRY, VOL. 5 1 , NO. 13, NOVEMBER 1979 · 1281 A
