4A
ANALYTICAL
CONTENTS,
CHEMISTRY
continued
NOTES, Contd.
?
get
ANTIFOAM A Foam wastes time; takes space; invites fire. Kill foam with Dow Corning Antifoam A, the most efficient and versatile defoamer on the market. This silicone defoamer is also most economical to use because only trace quantities are re quired to quell many of even the most violent and persistent foamers.
Coulometrie Titration of Unipositive Thallium with Either Bromine or Chlorine R. P. Buck, P. S. Farrington, and Ε. Η. Swift
1195
Infrared Absorption Spectrum of Toxaphene W. C. Kenyon
1197
Amperometric Titration of Zinc with Potassium Ferrocyanide A . L. Woodson, Β. Η. Johnson, and S. R. Cooper
1198
Analysis of Mixtures of Chloride and Bromide by Ion-Exchange Chromatography William Rieman III and Siegfried Lindenbaum
1199
Derivative Polarographic Titration of Glucose R. N. Adams, C. N . Reilley, and N . H. Furman
1200
Paper Chromatography of Nucleic Acid Derivatives D. C. Carpenter
1203
Differentiating Color Test for Fluorene Derivatives Eugene Sawicki
1204
Determination of 2,3-Dihydropyran by Bromination R. L. McCullough and K. G. Stone
1206
Modification of Mtllin's Rapid Method for Determining Carbon andlHydrogen in Organic Compounds S. S. israelstam
1207
Rapid Micro method for Determining Carbon and Hydrogen in Organic Compounds O . G. Backeberg and S. S. Israelstam
1209
Infrared Absorption Spectra of Porphyrins C. W. Craven, K. R. Reissmann, and H. I. Chinn
1214
Higb-Alkaline Colorimetric pH Determination R. H. M.Simon
1215
Method for Staining Cyclotols, Ednatols, Pentolites, and Picratols for Observation and Study of Non-TNT Phase 1216 Frank Pristera Luminol as Chemiluminescent Indicator in Photometric Titration of Solutions of High Opacity Frederic Kenny and R. B. Kurtz
1218
Determination of Arsenic in Organic Nitrogen Compounds of Guanidino Type
1219
W. C Stickler Molecular Structure and Spectroscopy
1223
Northwest Regional Meeting Chemical Institute of Canada
1228 .
Society of Public Analysts CRYSTALLOGRAPHIC
DATA
1,5-Diphenyl Carbohydrazide (Sym Diphenylcarbazide) Tar and fectively well as trations parts in
asphalt, for example, are ef defoamed during processing as during application by concen of Antifoam A as low as 4 10 million.
Ten ounces of Antifoam A added to a 40,000 gallon batch of crystallizing sodium bromide prevented foaming in that batch and in the next 21 batches as well. Here the effective concentra tion works out to about 1 part in 10 million. If cost, contamination, or full use of process equipment are prime consider ations In your operations, try Antifoam A. Practically odorless, tasteless and non-toxic, Antifoam A is safe, fast and by far the most economical and versa tile defoaming agent on the market.
1230 1231 1220
M . B. Williams, W. P. Van Meter, and R. J. Robinson BOOK REVIEWS
1221
THE ANALYST'S CALENDAR
1231
AIDS FOR THE A N A L Y S T Glass Unit for Liquid and Vapor Phase Extraction Employing Single Processing Chamber H. A. Sauer Versatile Electronic Manostat W. E; Erner and Κ. Ν. Campbell Improved Drilling Jig for Preparation of Porous Cup Electrodes S. H . Simonsen
1232
1232
1233
Twin-Shell Microblender for Powders L. E. O w e n
1234
Magnetic Stirrer for Cryoscopic Determinations J. L. Rabinowitz
1234
THE ANALYST'S C O L U M N
13 A
INSTRUMENTATION
19 A
R. H. M i l l e r NEW PRODUCTS
23 A
MANUFACTURERS' LITERATURE
26 A
See {o* tyousi&ell DOW
CORNING
SILICONES
Send for trial of Antifoam A
sample
Dow Corning Corporation Dept. CC Midland, Michigan
Name Company. Street City DOW
-State _ CORNING CORPORATION M i d l a n d , Michigan
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