analytical chemistry - ACS Publications - American Chemical Society

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ANALYTICAL CHEMISTRY Volume 20, No. 8

Copyright 1948 by American Chemical Society

Issued August 13, 1948

EDITOR: WALTER J. MURPHY Assistant

Assistant to Editor: N . A . PARKINSON

Editors

Advisory R. P. CHAPMAN Κ. Κ. CHEN

Executive Editor: JAMES M . CROWE

Manuscript Editing: G . GLADYS GORDON

Associate Editor: LAWRENCE T. HALLETT

Manuscript Reviewing: STELLA ANDERSON

ί- Ί ' C^UJL·^11

Make-up: CHARLOTTE C. SAYRE

B. L. CLARKE T. R. C U N N I N G H A M I. M . KOLTHOFF

Contributing Editor: R. H . MULLER

EDITORIAL

689

Board G. E. F. LUNDELL M. G. MELLON R H

· ·

MLi

LLER

B. L. OSER W. J. SWEENEY H. H . WILLARD

Storage and Titration with Oxygen-Sensitive Solutions . . . H . W . Stone

747

Spectrophotometric Determination of Phosphorus as M o l y b diphosphoric A c i d . . . D . F. Boltz w i t h M . G . M e l l o n

749

Determination of Unsaturation in Dehydrogenated Diethylbenzene R. P. Marquardt and E. N . Luce

751

Mass Spectra of Some Organic Compounds R. H . Roberts and S. E. J . Johnsen

690

Depolymerization of Butylène Polymers F. G . Ciapetta, S. J . Macuga, and L. N . Leum

699

Determination of Functionality in Methyl Silicone Systems . G . F. Roedel

705

Reduction System

of Noise in a Spectrophotometer Recording Carroll Creitz

Estimation of Small Amounts of Ο , Ο - D i e t h y l O,p-Nitrophenyl Thiophosphate. .P. R. A v e r e l l and M . V . Norris

753

707

Instrument for Measuring Stress Relaxation of High Polymer Materials W . S. Macdonald and Alexis Ushakoff

Determination of Vitamin A Ester in Fortified Poultry Mashes M . E. W a l l and E. G . Kelley

757

713

Determination of Free Carbon in Compounded Rubber and Synthetic Elastomers G . D. Louth

Spectrophotometric Determination of Serum Calcium . . . J . A . W e y b r e w , Gennard Matrone, and H . M . Baxley

759

717

Determination of Carotene in Plant Materials Arunachala Sreenivasan and R. M . Vaidya

720

Colorimetric Determination of Copper with Carbon Disulfide W . C. W o e l f e l

722

Aromatic Compounds in Petroleum Products . A . L. Conrad

and Diethanolamine

725

728

Determination of Diphenyl Carbonate Jerome Goldenson and Samuel Sass

730

Determination of Phosphorus in Hexaethyl Tetraphosphate and Tetraethyl Pyrophosphate Martin Jacobson and S. A . H a l l Analysis of 1,2,3,4,5,6-Hexachlorocyclohexane for Gamma Isomer Gerrit Dragt Rapid Evaluation of Solvent Extraction Processes H . A . Bewick, J . E. Currah, and F. E. Beamish Determination of Specific Gravity of Pigments W . W . Ewing and R. N . Rhoda Colorimetric Determination of Certain Dinitro Aromatics. . F. L. English

Sidney Siggia and R. L. Edsberg

762

Composition of Vapors from Boiling Solutions.D. F. Othmer

763

Modified Glycerol Dichlorohydrin Reaction for Vitamin D: J . A . Campbell

766

MICROCHEMISTRy

Chromatographic Separation of Aliphatic 2,4-Dinitrophenylhydrazones J . W . W h i t e , Jr. Accumulation of Traces of Arsenate by Coprecipitation with Magnesium Ammonium Phosphate I. M . Kolthoff and C. W . Carr

Determination of Boiling Range of Methyl Bromide. . • . Dwight Williams and C. C. Meeker

lodometric Determination of V i n y l A l k y l Ethers

726

Determination of Lead in A i r L. J . Snyder, W . R. Barnes, and J . V . Tokos

NOTES O N A N A L Y T I C A L Ammonium Copper

Citrate

772

PROCEDURES

in Colorimetric Determination of A . J . Hall and R. S. Young

776

733 Determination Compounds

in Organic B. L.Johnson

777

736

Division of Analytical and Micro Chemistry Issues List of Speakers

780

737

CRySTALLOGRAPHIC DATA

779

BOOK REVIEWS

78Ο

THE ANALYST'S CALENDAR

JQ-]

740 743

of

Hydroxyl

AIDS FOR THE ANALYST THE ANALYST'S COLUMN

745

The American Chemical Society assumes no responsibility for the statements and opinions advanced by contributors to its publications- Views expressed in the edi­ torials 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 and Editorial Headquarters, 1155 Sixteenth St., N. W., Washington 6, D. C. Advertising Office: 332 West 42nd St., N e w York 18, Ν. Υ. Branch Editoria I Offices: Chicago 4 , l l l . , Room 819, 25 East Jackson Blvd.; Houston 2, Tex., 413 West Bids-/ 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., February 18, 1948, under the Act of March 3, 1879, as 12 times a year monthly on the 1 5th. Acceptance for mailing at special rate of postage provided for in Section 1103, Act of Oct. 3, 1917, authorized July 13, 1918. Annual subscrip-

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