Modem Coulometry with Modem Instrumentation
W A N G ANNOUNCES The World's Second Most Powerful Calculator
Controlled-Potential Coulometer System
Practically every engineer and scientist needs a calculator with built-in logs, exponents, trig, storage and programming. But not everybody needs the Wang 700 — the World's most powerful calculator. That's why Wang designed the Model 500 — it's easy to use yet powerful. A n d a 500 can be expanded by simply adding internal components: extra memory, a cassette storage system and a printer. Y o u can go all the way up to 16,000 program steps and never have to send your 500 out of your office. Yet the basic 500 costs less than $3,000. For expandability and versatility the Wang 500 is second to none — except of course the Wang 700. If you d o n ' t need the World's most powerful calculator — or if y o u do — Call Mr. Courtney, collect, at 61 7-851-7211 for complete information. ι _ _ _ _ _ _ _ _ _ _n Wang Laboratories, Inc. Dept. AC-4 836 North Street, Tewksbury, Mass. 01876 I'd like a 500 demonstration as soon as possible. Call me at for a date. (Phone number) Name
Model 3
$3906.25
• 0.1% Accuracy and Precision with mg amounts of: Ag As Au Br^ Cd Cl~ Cr Cu Eu Fe H202 I " In Ir Mn Mo Ni N r Np Pb Pu Ru Sb Sn Tc Tl U V Zn Numerous organic compounds φ Preparative Electrolysis φ Mechanistic and Formal E° Studies • Condensed Specifications: POTENTIOSTAT—Output: ± 24V, ± 400mA, Ζ = 1 ohm DC O.L. Gain = 105, fc = 750kHz, adjustable response Zero Stability: ± 0.5 mV long term INTEGRATOR—Ranges: 1.9 and 19 coulombs Drift: ± 0.5 mV/15 min., stable long term Calibration Stability: ± 0.1%/year
M-T ELECTRONICS CO.
Company. Street .State.
City
Premium quality, solid-state components for long-term reliability and stability Simplified controls Direct readout(1 volt = lmg) Self-checking configuration Modular, plug-in Potentiostat and Integrator available separately Negligible zero drifts
536-A Lewelling Blvd. San Leandro, Calif. 94579
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ACID DIGESTION BOMB ADSORPTION FROM AQUEOUS SOLUTION
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PARR Provides a r a p i d a n d safe m e t h o d f o r dissolving glass, silicates, n i t r i d e s , rocks a n d o t h e r refrac tory materials in HF, HC1 a n d o t h e r s t r o n g m i n e r a l acids at t e m peratures t o 150° C. a n d pressures t o 1200 psig. Acids do not attack this b o m b and c o m p l e t e re covery is assured, i n c l u d ing any trace elements.
ADVANCES IN CHEMISTRY SERIES NO. 79 Fifteen papers from a symposium by the Division of Water, Air, and Waste Chemistry and the Division of Colloid Chemistry of the American Chemical Society, chaired by Walter J. Weber, Jr. and Egon Matijevic. The papers in this volume deal with many of the questions and problems relating to adsorption from aqueous solution, as well as general discussions of thermodynamic and kinetic aspects of adsorption phenomena. The papers include descriptions of the results of studies on a variety of adsorbate-adsorbent systems. 212 pages with index
The acid charge is held in a 25 ml. thick walled Teflon* cup within a sturdy metal bomb. The cup can be removed for convenient sample recovery and easy washing. No wrenches or clamps are needed to produce a tight seal. *duPont TFE flurocarbon resin Write for Data Sheet 4745
Free set of L. C. cards with library orders upon request.
Cross-Section Diagram
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ANALYTICAL CHEMISTRY, VOL. 4 3 , NO. 4 , A P R I L 1 9 7 1
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