analytical chemistry - ACS Publications - American Chemical Society

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ANALYTICAL

CHEMISTRY Issued August 13, 1949

Copyright 1949 by American Chemical Society

Volume 2 1 , No. 8

EDITOR: WALTER J. MURPHY Executive E d i t o r :

Assistant t o E d i t o r :

N . A . PARKINSON

Assistant Manuscript Editing:

Contributing Editor:

G . GLADYS G O R D O N STELLA ANDERSON

B. L. OSER

RUTH CORNETTE

I. M . KOLTHOFF

J . W . STILLMAN

M I L D R E D E.

H . A . LAITINEN

W . J . SWEENEY

M . G . MELLON

EDWARD WlCHERS

Benzene, Toluene, Ethylbenzene, o-Xylene, m-Xylene, and p-Xylene · * D. D. Tunnicliff, R. R. Brattain, and L. R. Zumwalt

. . . L. K. Nash

980

890

983

Determination of Potash in Fertilizers

984

900

Determination of Impurities in η-Heptane Concentrates by Infrared Absorp­ tion J. A . Anderson, Jr., and C E. Zerwekh, Jr.

911

Infrared Spectroscopic Determination of Ester Carbonyl R. R. Hampton and J . E. Newell

914

R. M . Elofson

917

R. W . Martin

Infrared Analysis of Low Temperature Polymers R. R. Hampton Determination of Styrene in Hydrocarbon Copolymers R. C. Crippen and C. F. Bonilla

919 921

934 936

Quantitative Spectrochemical Determination of Lead and Zinc in Ores . .

G. F. Smith and W. W. Brandt

Determination of Starch and Cellulose with Anthrone F. J. Viles, Jr., and Leslie Silverman Dichromate Reflux Method for Determination of Oxygen Consumed . . . W. A . Moore, R. C Kroner, and C. C. Ruchhoft Extraction of Carotene from Green Leaves

V . H. Booth

991

Determination of Lactose in Milk Products B. D. Hites, C. W. Ackerson, with G. H. Volkmer

993

C. J. Rolle and T. L. Dietrich

996

Analysis of Hydrocarbon Mixtures H. E. Morris, W. H. Lane, and R. B. Stiles

998

Evaluation of Paint Films

MICROCHEMISTRY Microdetermination of Iodine in Materials with High Organic Content B. K. Shahrokh and R. M . Chesbro 1003

Rapid Identification of Manganese Dioxide Ores G . A . Marsh and H . J . McDonald

5,6-Dimethyl-1,10-phenanthroline

986 989

Determination of Hydrogen

Colorimetric Determination of Capsaicin in Oleoresin of Capsicum . . . . Horace North

M . J . Murray

Isoquinoline as Reagent in Inorganic Analysis A . E. Spakowski and Henry Freiser Determination of Benzaldehyde in Benzyl Alcohol H. L. Rees and D. H . Anderson Direct Colorimetric Method for Carbohydrates. Maltose G . H. Benham, and V . E. Petzing

927 930

M . H . Hubacher

C. H . Perrin

923

Spectrophotometric Determination of Cobalt as Cobalt(ll) Chloride in Ethanol · G . H . Ayres and B. V . Glanville

Isidore Schnopper and Isidore Adler

GILLESPIE

Indirect Colorimetric Determination of Gaseous Fluorine

Identification of Pennsylvania Lubricating Oils by Infrared Absorption . . Mark Fred and Richard Putscher

J. M . Hustler and E. M . Hammaker

DRAPER

Routine Determination of Nickel in Cobalt-Base Alloys Louis Silverman and H. K. Lembersky

895

Spectrosraphic Determination of Trace Elements in Silica

Assistants

889

Correction for Interfering Absorption in Spectrophotometry Analyses . . . D. D. Tunnicliff, R. S. Rasmussen, and M . L. Morse

Determination of Carboxy Group in Aromatic Acids. .

R. H . MÜLLER C . J . RODDEN

EDITORIALS

Total Phenols in Gasolines and in Cresylic Acids

R. P. C H A P M A N J . R. CHURCHILL

E I L E E N F.

Rapid Estimation of Ethylenes

R. H . MÜLLER

Board

Κ. Κ. C H E N

CHARLOTTE C . SAYRE

Polarography of Cyclo-octatetraene

Advisory

LAWRENCE T. H A L L E T T

Editorial

Editors

Manuscript Reviewing: Make-up:

Associate E d i t o r :

JAMES M . CROWE

939 941 945

L. P. Pepkowitz and E. R. Proud

1000

Spectrophotometric Determination of Microquantities of Iodine . . . . J. J. Custer and Samuel Natelson 1005 Microdetermination of Riboflavin by Synthetic Ion Exchange Resins . . Motonori Fujiwara and Hiroshi Shimizu 1009 NOTES O N A N A L Y T I C A L PROCEDURES Volumetric Determination of Small Amounts of Iron W. D. Cooke, Fred Hazel, and W. M . McNabb

1011

Comparison of Tellurium and Selenium as Catalysts forKieldahl Digestion R. B. Bradstreet 1012

948

Simplified Gas Microanalyzer C. N . Stover, Jr., W. S. Partridge, and W . M . Garrison

950

Laboratory Induction Stirrer for Closed Systems B. M . Tolbert, W. G . Dauben, and J . C. Reid 101 4 Modified Method of Charging Poth Carbon Dioxide Generator

953 957

Correction—Microscope Hot Stage

1013

. . . .

P. L. Pickard

1015

F. W . Matthews

101 7

Division of Analytical and Micro Chemistry List of Speakers Analytical Round-Table Discussion at Atlantic City

1018 1019

Stability of Vitamin A Acetate under Laboratory Conditions M . E. Chilcote, N . B. Guerrant, and H. A . Ellenberger Amperometric Determination of Primary and Tertiary Mercaptans . . . . I. M . Kolthoffand W. E. Harris J. B. Martin and D. M . Doty Determination of Inorganic Phosphate

963

CRYSTALLOGRAPHY D A T A

1016

965

CORRESPONDENCE

1017

Quantitative Determination of Thiophenol, Diphenyl Disulfide, and Phenyl Thiolacetate D. P. Harnish and D. S. Tarbell

BOOK REVIEWS

1018

968

THE ANALYST'S C A L E N D A R

1019

Titration of Thiocyanate .

970

AIDS FOR THE A N A L Y S T

1020

Robert Bastian

972

THE ANALYST'S C O L U M N

17 A

lodometric Determination of Copper. . . E. W . Hammock and Ε. Η . Swift

975

INSTRUMENTATION

23 A

E. W. Hammock, David Beavon, and Ε. Η. Swift

Determination of High Percentages of Copper

The American Chemical Society assumes no responsibility for the statements and opinions advanced by contributors to its publications. Views expressed in the editorials are those of the editors and do not necessarily represent the official position of the American Chemical Society. Published by the American Chemical Society, from 20th and Northampton Sts., Easton, Pa. Executive Offices, Editorial Headquarters, and Circulation Department, 1155 Sixteenth St., N . W., Washington 6, D. C. Advertising Office: 332 West 42nd St., N e w York 18, Ν . Υ. Branch Editorial Offices: Chicago 4, III., Room 819, 25 East Jackson Blvd.; Houston 2, Tex., 424 West Bldg.,· N e w York 17, 60 East 42nd St.; San Francisco 2 , Calif., Room 454, 760 Market St. Entered as second-class matter at the Post Office at Easton, Pa., U.S.A., February 18, 1948, under the A c t of March 3, 1879, as 12 times a year monthly on the 15th. Acceptance for mailing at special rate of postage provided for in Section 1103, Act of O c t . 3, 1917, authorized July

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