CONTRIBUTED ARTICLES iimiMiimuiiiiiiiiiiiiiiiiimmiiiiiiiiiiiiiiiniiiiiiiiiiiHiuiiDi
Counter Double Current Distribution: Effects of Vary ing Number of Stages. R. O. Butterfleld, c. K. Tjarks,
Evaluation of Correction Procedures Used in Electron Probe Microanalysis with Emphasis on Atomic Num ber Interval 13 to 33. D. R. Beaman
418
Determination of Traces of Lead in Air by Atomic Absorption Spectrometry. Georges Thilliez
427
Determination of Spectrometry.
Antimony
by Atomic
Absorption
R. A. Mostyn and A. F. Cunningham . . .
433
and H. J. Dutlon
497
Time-Resolved Phosphorimetry as a Method of Simul taneous Analysis of Two-Component Mixtures. P. A. Si. John and J. D. Winefordner
500
An Instrumental Method for Rapid Determination of Carbonate and Total Carbon in Solutions, c. E. Van Hall and V. A. Stenger
Derivation of Expressions for Calculation of Limiting Detectable Atomic Concentration in Atomic Fluores cence Flame Spectrometry. J. D. Winefordner, M. I. Parsons, J. M. Mansfield, and W. J. McCarthy
436
Transfer Coefficients and Heterogeneous Rate Con stants for Cadmium(ll) in Various Supporting Electro lytes Evaluated by Phase-Angle Measurements with an A.C. Timniek
Spectrophotometric Determination of Unsaturated Pyr r o l i d i n e Alkaloids. A. R. Mattocks
443
Polarograph.
J. K. Frischmann and Andrew 507
Determination of Total Oxygenates in Organic M a terials for Levels Down to 5 ppm by Gas Chroma tography. C. F. Meade, D. A. Keyworth, V. T. Brand, and J. R. Deering
Experimental Sensitivities in Neutron Activation and Gamma Spectrometry with a 1 50-kV Accelerator. Jean Perdijon
503
512
448
Identification of Polyurethanes by High Resolution Nuclear Magnetic Resonance Spectrometry, E.G. Brame, Jr., R. C. Ferguson, and G. J. Thomas, Jr
Alternating and Direct Current Polarography of Azobenzene in Indifferent Electrolyte in Dimethylformamide.
G. H. Aylward, J. L. Garnett, and J. H. Sharp . . .
517
457
Notes Complexation of Scandium(lll) with 8-Quinolinol. Petronio and W. E. Ohnesorge
J. N.
. . . . .
460
Gas Chromatographic Analysis of Dilute Aqueous Systems.
W. G. Jennings and H. E. Nursten
521
Detection Limits of Elements in the Spectra of Premixed, Oxy-Acetylene Flames. V. A. Fassel and D. W. Golightiy 466
Principles of Stationary Phase Selectivity in G a s Liquid Chromatography, s. H. Langer
Polarography of Aquodiethyltin(IV) Cation in Aqueous
Spectrophotometric Determination of Manganese (VII) by Reduction with 6-Methoxy-2-Methylthio4-Pyrimidine Carboxylic Acid. ο. κ. Chung and
Solution.
M. D. Morris
470
C. E.Meloan
Simultaneous and Independent Potentiostatic Control of Two Indicator Electrodes. Application to Copper(ll)/Copper(l)/Copper System in 0.5M KCI at Rotating Ring-Disc Electrode. D. T. Napp, D. c Johnson, and Stanley Bruckenstein
P. J. Lingane
Aart Jurriaanse and F. L. Moore
527
481
Solvent Fractionation of G i r a r d T Derivatives of Carbonyl Compounds Using Dimethyl Sulfoxide. 485
Use of Organic Additives to Induce Selective L i q u i d Liquid Extraction of Niobium with Thenoyltrifluoroacetone.
525
Internal Standard Techniques for Determination of O x y g e n in Magnesium, Steel, and Titanium by Ac tivation Analysis. B. L. Twitty and Κ. Μ. Fritz . . . .
Critique of Chronopotentiometry as a Tool for the Study of Adsorption.
524
S. F. Osman and J. L. Barson
530
Determination of Ephedrine and Certain Related Compounds by Ultraviolet Spectrophotometry. 494
J.E.Wallace
531 VOL. 39, NO. 4, APRIL 1967
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3 A
CONTRIBUTED ARTICLES
Whatman ADVANCED ION-EXCHANGE CELLULOSES
General Information Advanced Ion Exchange Celluloses Microgranular Table of Properties Fibrous Table of Properties Composition Advanced Ion Exchange Celluloses Microgranular Microstructure Fibrous Microstructure Properties Particle Size and Form Capacity and Kinetics of Exchange Water Regain Column Bed Volumes Column Flow Rates Precycling Choice of Physical Form Column Separations Microgranular Fibrous Batchwise Operations
Study of Xenon—Mercury Arc as a Continuous Source for Atomic Absorption Spectrometry, C. W. Frank, W. G. Schrenk, and C. E. Meloan
534
Simultaneous Determination of Tin and Lead Using Cyclic Stationary Electrode Polarography. S. I. Phillips
536
Estimation of Molybdenum in Biological Material by Neutron Activation Analysis. H. D. Livingston and Hamilton Smith
538
Correspondence "Krypton Triode" as Selective Detector for Gas Chromatography. C. D. Pearson and R. S. Silas . . .
540
Re-Evaluation of Chronopotentiometric Data Adsorption of Riboflavin, p. j . Lingane
541
for
Recommendations for the Reporting of Thermal Analysis Data. H. G. McAdie
543
A i d s for A n a l y t i c a l Chemists
G a s C h r o m a t o g r a p h i c M e t h o d f o r S m a l l Amounts o f W a t e r V a p o r in A i r . D. E. Burke, G. C. Williams, and C. A. Plank
544
E x c h a n g e a b l e Injection Port C a r t r i d g e f o r G a s Chromatographic Determination of Volatile Substances in A q u e o u s Fluids. Gerhard Freund
545
R a p i d S o n i c a t i o n Technique f o r L i q u i d Scintillation Counting o f C a r b o n - 1 4 - L a b e l l e d Barium C a r bonate. J. B. Allred
547
N i t r o g e n A n a l y s i s o f N i t r a t e Esters b y M i c r o - D u m a s Combustion. P. Borda and L. D. Hayward
548
Q u a l i t a t i v e D e t e c t i o n o f Boron v i a Derivative. George Vogel
549
Microgranular Choice of Exchanger Type Choice of Buffer Laboratory Methods General Handling Storage Usage Exchanger Preparation Precycling Equilibration Removal of Fines Slurry Preparation and Degassing Column Separations Pouring Microgranular Series Fibrous Series Column Preparation Sample Introduction Batchwise Techniques Re-Use
a
Crystalline
Applications Ordering Information
ra
Technical Bulletins and Catalog
·
^50
A n o m a l o u s C a l i b r a t i o n Curves in G a s C h r o m a t o g r a p h y of High-Boiling Compounds. M. M. E. Metwally, C. H. Amundson and T. Richardson
55 I
SCIENTIFICA DIVISION
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S p e c t r o p h o t o m e t r i c A s s a y o f the T r i p h e n y l m e t h y l Group. R. M. Saunders, H. P. Sehwarz, and J. C. Stewart
ANALYTICAL CHEMISTRY