NEWS
Fast-accurate
SULFUR analysis W
ALloYs
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with a
DIETERT-DETROIT Sulfur
Determinator T h e Dietert-Detroit Sulfur Determinator features an extremely simple direct-reading burette. No involved measuring or computing. Provides fast accurate analysis of sulfur content in scores of materials. Low cost, durable, easily maintained. Widely used in company ^ laboratories and i n s t i t u t i o n s of every description for over 18 years.
Dietert-Detroit Sulfur Determinator No. 3104, with combustion Furnace.
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Catalog!
16page Dietert-Detroit Catalog illustrates and describes both Sulfur and Carbon Determinatorsand complete line of accessory equipment and supplies.
HARRY W. DIETERT CO. CONTROL 9330 ROSELAWN
EQUIPMENT T
DETROIT 4 , MICHIGAN
Send me your latest Carbon-Sulfur D e t e r m i n a t o r catalog. NAME COMPANY ADDRESS CITY . STATE Circle No. 34 A on Readers' Service Card, page 77 A 3 4
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ANALYTICAL
CHEMISTRY
A major responsibility of scientists is to convince secondary school students that science is a challenging career, Paul M . Gross (center), vice presidnent, Duke University, stated a t the Analytical Division dinner. Divisional officers R. P. Chapman (right), American C y a n a m i d , chairman, and W a r r e n Brandt, Purdue University, secretary-treasurer, discuss this topic with Gross
capillary siphon flow. T h e filter paper, which is narrower a t the top t h a n a t the bottom, is supported a t a slight incline on solidified polystyrene foam. A cover of polyethylene sheeting prevents evaporation of the solution. T h e apparatus has been applied t o such ions as silver and copper, cobalt and iron, silver and cadmium, and bism u t h and aluminum. More information concerning temperatures a t which various intermediates a n d final reaction products are formed can be obtained from a simple differentiator, Clement Campbell, Picatinny Arsenal, reported. I t consists of a precision, single-turn transmitting potentiometer mounted on the slidewire shaft of a recorder used to obtain the thermogram. A recording differential refractometer, originally designed for process control, such as monitoring effluents from adsorption and partition chromatography columns and ion exclusion columns, is sensitive enough (10~*) for use as a laboratory instrument. This development is the work of P . B . Moseley and R. H . Osborn, Hercules Powder Co., and P . W. Collyer, Barnes Engineering Co. A completely automatic, recording cryoscopic apparatus, described b y E . L. Simons, General Electric Research Laboratory, has a unique way of controlling supercooling. A stream of precooled nitrogen gas impinges on the b o t t o m of the cell containing the liquid
t o be frozen. Crystallization of t h e supercooled liquid is induced quickly. As the temperature rises toward t h e freezing point of the liquid, the nitrogen stream is automatically cut off. D . M . Rosie, Esso Research a n d E n gineering Co., found t h a t , contrary to prior assumptions, the thermal conductivity differences between similar h y d r o carbons even when measured against helium, m a y be significantly large. When correction is made for these thermal conductivity differences, precise quantitative results are obtained in using gas chromatographs with thermal conductivity cells. A gas chromatography apparatus, suitable for analyses of impurities a t the p a r t s per million level was described b y C. E . Bennett, E . I . du P o n t de Nemours & Co., Inc. This instrument uses a direct-current amplifier in conjunction with a thermistor detector. Typical applications are traces of isopropyl alcohol in benzene, benzene in toluene, methanol in water, a n d cyclohexanol in toluene. An automatically operated, modified gas chromatograph instrument for laboratory use was described b y Nathaniel Brenner, Perkin-Elmer Corp. A oneinch diameter column, one meter long, fits directly into a standard gas chromatography apparatus. Use of automatic controls t o operate sample injection a n d sample collection devices provides a system for continuous, a u t o matic preparation of pure samples.
