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TIMERS
Volumetric Determination of Calcium in Presence of Phosphate
1230
R. G. Y a l m a n r William Bruegemann, P. T. Baker, and S. M . Garn
have been
6ALLET TIMERS
offered by
RACINE
Kinetics of Oxidation of Bromide Ion in Fused Alkali Nitrate Solutions of Dichromate
1 GALLET I
1233
F. R. Duke and M . L. Iverson
CHRONOGRAPHS
Sensitive Colorimetric Method for Determination of Fructose
L. E. Hessler
1 234
Platinum-Flux Technique for Determining Oxygen in
FOR RESEARCH
T i t a n i u m . W . R. Hansen, M . W . Mallett, and M . J. Trzeciak
Ί 237
Rapid Colorimetric Method for Determining Glyoxal
1 241
FOR PRODUCTION C. S. Wise, C. L. Mehltretter, and J . W . V a n Cleve
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JULES RACINE & COMPANY, INC. Spetiolufi in Fine Timen — Since 1890 20 WEST 47th STREET, NEW YORK 36, Ν. Υ.
Comparison of Two Species of Lactobacilli as Test Organisms in Pantothenic Acid Estimation, tacfobacillus Casei and Lactobacillus Plantarum . . . .
Modified 4-Aminoantipyrine Colorimetric Method for Phenols. Application to Acrylic Monomer . .
1246
R. J. Lacoste, S. H. Venable, and J . C. Stone
Automatic Atmospheric Fluoride Pollutant Analyzer .
Circle No. 18 on Readers' Service Card
1243
M. F. Clarke
1 249
D. F. A d a m s and R. K. Koppe
ffîT/^£ov=APIEZON®
Automatic Sulfate Ion Analyzer
A P I E Z O N = 7he Finest Oils, Waxes and Greases for High Vacuum Work
Simple Ultraviolet Photometer
P r e f e r r e d by l e a d i n g scientists for high vacuum equipment and systems where low pressure process is used a t one or more stages. • V a c u u m c o a t i n g units and vacuum furnaces for degassing of metals . · M e t a l l u r g i c a l vacuum . distillation of light metals • Lyophilic drying of penicillin, vitamins and other substances • Preparation of concentrates
vitamin
1 255
H. N . Claudy, F. W . Karasek, B. O . Ayers, and J. G . Skinner
1258
R. E. Thiers, M a r v i n Margoshes, and B. L. Vallée
Isomer Ratio Analyzer for Toluenediisocyanate Based on Dielectric Constant Measurements
1261
Samuel Steingiser, W . C. Darr, and Ε. Ε. Hardy
Microdetermination of Methoxyl and Ethoxyl . . .
1 265
R. F. Makens, R. L. Lothringer, and R. A . Donia
Microgas Cell for Infrared Spectroscopy
1267
J. U. White, N . L. Alperf, W . M . W a r d , a n d W . S. C a l l a w a y
Semimicrodetermination of Combined Tantalum and Niobium with Selenous Acid
1 270
F. S. Grimaldi and M a r i a n Schnepfe
• Dehydrated food • Blood serum drying . · The electron microscope As exclusive distributor in the United States, we offer immediate delivery from stock on the compl^tp range of Apiezon oils and compounds. Γοι details on applications, working characteristics and list prices, write for Bulletin 43-AC -from fin· Greet wearing
JAMES 13 1 6
"w il.uj* pressura"
G.
BIDDLE
Electrical & Scientific /nsfrim ARCH PHILADELPHIA Circle No. 24 on Readers' Service Card
6 A
·
ANALYTICAL CHEMISTRY
eei2
CO. 7,
Microscopic Identification of Microgram Quantities of Galacturonic Acid and Glucuronolactone. Direct Synthesis of Hydrazone Derivatives by Solvent Diffusion Technique
1 273
L. M . White and G. E. Secor
Carbon and Hydrogen Microdetermination by Automatic Combustion Control . . . . Ervin Stehr
1 274
Correction
1 1 59
