MINI
NEWS
MONITOR THE ECONOMY TOOL FOR
ULTRA-VIOLET ANALYSIS OF COLUMN EFFLUENT
I n s t r u m e n t exhibition in the Lobby of the Auditorium Maximum, Hamburg State University
A great new labor-saver! Watches and records U V absorption of column effluent before the fraction collector, producing absorption peaks on a strip chart to tell you which fraction tubes contain material of interest. Entire instrument, including recorder, is self-contained in one cabinet only 7" cubed and weighing only 10 pounds. Mounts directly on the stand of any fraction collector. % T recording; 254 mu peak radiation; event m a r k e r to r e c o r d fraction changes; range expander for sensitivity adjustment. For use with proteins, nucleic acids, or other materials having reasonable absorption at 254 mu.
ORDER NOW FOR IMMEDIATE DELIVERY... ONLY $790 f.o.b.
Bethesda,
Md.
CANALCO CANAL INDUSTRIAL CORP. DepL A-J 4935 Cordell Avenue Bethesda 14. Maryland Circle No. 152 on Readers' Service Card 8 0 A
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ANALYTICAL
CHEMISTRY
ficient for the combustion of even the slowest burning compounds. The sensitivity of detection was 12.5 mv. ju.gr1 seer 1 for amyl alcohol and was proportional to the heat of combustion of the solute. The combination of a conventional mass spectrometer with a gas chromatograph was shown to be useful for the identification of 37 components in a gasoline cut by Henneberg and Schomburg. The application of characteristic masses for class identification, such as mass 91 for alkylbenzenes, was reviewed. Jentzsch and Hôvermann, in a study of relatively large diameter (0.5 mm. i.d., 100 m. long), coated capillary columns, showed that samples as large as 50 jul. could be injected, allowing the use of thermal conductivity detectors and eliminating the need for sample splitters. Two methods for reducing tailing in capillary columns were suggested: (1) coating the capillary with an inert, temperature-stable "intermediate phase" such as silicone rubber SE-52 [General Electric Co.] prior to application of the stationary phase and (2) the addition of a corrosion inhibitor such as "Alkaterge T," as originally proposed by Averill at the 1961 Michigan State Symposium. The hydrogen isotopes and nuclear spin isomers, ortho- and parahydrogen, ortho- and paradeuterium and hydrogen deuteride were completely separated by Mohnke and Saffert by adsorption chromatography using capillary columns operated at 77.6° K. A 20 μ thick adsorptive layer on the inner wall of a glass capillary 80 m. in length
was prepared by etching the sealed capillary with a 17% aqueous ammonia solution at 170° for 70 hours. Neon was used as carrier gas. Schulz presented a quantitative dis cussion of the continuous countercurrent separation of a number of binary mixtures. A feed mixture of isobutene (b.p., —6.9°) and n-butene-1 (b.p., —6.26°) was separated, with both com ponents being reclaimed in greater than 99% purity, by continuous feed ing of the mixture into the center of the column while allowing a sorption material of silver nitrate in benzyl cyanide on Sterchamol to move in a countercurrent direction to the carrier gas flow. Kaiser and Kienitz pointed out that gas chromatographic equipment could pay for itself within a period of 10 days to 1 month when used under the right conditions in process control systems. The application of a process control unit to distillation problems was re viewed.
Applications T. R. Phillips and D. Neylan pre sented a statistical study of factors af fecting column performance in the separation of halogen and interhalogen compounds on Kel-F oils. One obser vation, not in accordance with estab lished theory, was that a liquid phase loading of 20% Kel-F oil on Kel-F Grade 300 molding powder gave better column performance with 50-70 mesh particles than with finer size particles while a high loading of 80% gave better
