Contributed Articles
General Analysis of Potentiostatic Current-Time Curves for Cylindrical Electrodes. Sidney Barnartt and C. A. Johnson Simultaneous Determination of Silicate and Phosphate by an Automated Differential Kinetic Procedure. J. D. Ingle, Jr., and S. R. Crouch Radioisotopic X-Ray Analysis of Silver Ores Using Compton Scatter for Matrix Compensation. P. G. Burkhalter Application of Field Ionization to Gas-Liquid Chromatography-Mass Spectrometry (GLC-MS) Studies. J. N. Damico and R. P. Barron Machine Intelligence Applied to Chemical Systems. Prediction and Reliability Improvement in Classification of Low Resolution Mass Spectrometry Data. P. C. Jurs Double Beam Photon Counting Photometer with Dead Time Compensation. K. C. Ash and Ε. Η. Piepmeier Chlorine-35 Nuclear Quadrupole Resonance Studies of Trichloromethyl Compounds. E. G. Brame, Jr.
Time-Lapse Spectrometry in Organic Photochemistry. N/co/ae Filipescu, F. L. Minn, and J. W. Pavlik
83
The Question of Instrumental Artifact in Linear Sweep Voltammetry with Positive Feedback Ohmic Drop Com pensation. E. E. Wells, Jr.
87
Photon Activation Analysis—A Review.
93
2
7
10
17
22
26
G. J. Lutz
Use of Static Argon Atmosphere in Emission Spectrochemical Determination of Chromium in Biological Materials. Κ. M. Hambidge
103
Mixed Carrier Gases in Chromatography—A Source of Error. Raymond Annino, Joseph Franko, and Harry Keller
107
Micro and Ultramicro Analyses by Null Point Pressuremetry and Coulometry: Hydrogénation and Hydrogenolysis. D. J. Curran and J. E. Curley
118
Analysis for Impurities by Nuclear Scattering. Cohen and R. A. Moyer
123
B. L.
35
Notes Cryoscopic Determination of Number-Average Molecu lar Weight by Quartz Crystal Thermometry. J. S. Fok, J. W. Robson, and F. C. Youngken Accuracy of Analysis by Electrical Detection in Spark Source Mass Spectrometry. R. A. Bingham and R. M. Elliott Radioactive Tracer Technique for Molecular Diffusion Coefficients in Granular Media. E. R. Bennett and W. E. Bolch Spectrophotometric Analysis of Carbonyl Compounds in the Presence of Carbohydrates without Prior Separa tion. Ε. Β. Sanders and Jack Schubert Polarographic Determination of Traces of Nitrilotriacetate in Water Samples. J. P. Haberman Selectivity in Liquid-Liquid Chromatography. Marine and D. C. Locke
38
Potentiometric Study of Copper(l) Complexes with Uni valent Anions in Acetonitrile. J. K. Senne and Byron Kratochvil
129
Solvent Effects in Gel Permeation Chromatography. G. Bergmann, L. J. Duffy, and R. B. Stevenson
131
J.
43 Interference of Lithium in Atomic Absorption Spectrometry. A. M. Bond and D. R. Canterford
134
Spectrofluorometric Determination of Traces of Fluoride Ion by Ternary Complex Formation with Zirconium and Calcein Blue. T. L. Har and T. S. West
136
Fluorometric Methods for Determination of Europium and Terbium. D. E. Williams and J. C. Guyon
139
Spectrophotometric Determination of Sulfide Ion with Organic Disulfides. R. E. Humphrey, Willie Hinze, and W. M. Jenkines III
140
74
Determination of Nitrite by Controlled-Potential Coulometry. J. E. Harrar
143
79
Spectrophotometric Determination of Rhodium with Nitroso R. Formula for the Rh(lll)-Nitroso R Complex. O. W. Rollins and M. M. Oldham
146
55
59
63
D. £.
Pyrolysis Gas Chromatography of Phenyl Polymers and Phenyl Ether. M. T. Jackson, Jr., and J. Q. Walker
Sodium Removal as an Aid to Neutron Activation Analysis. H. R. Ralston and E. S. Sato
68
ANALYTICAL CHEMISTRY, VOL. 43, NO. 1, JANUARY 1971
·
3A
Contributed Articles
AP 100
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Determination of Polymeric Isocyanate in the Presence of Reactive Halides.
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Evaluation of Methods for Iron in Reduced Iron Ores.
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S. C. Blum and T. D. Searl
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150
Magnesium
C. O. Huber, K.
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152
NEW APIEZON anti-seize greases stop costly laboratory glassware breakage A P - 1 0 0 is a h i g h v a c u u m C o m p l e t e l y effective in tests grease for use down to against a wide range of a g 5 x 1 0 - 1 1 torr at 1 5 ° C , with a gressive solvents over peri s o f t e n i n g point of 3 0 ° C . ods of 72 hours a n d more. A P - 1 0 1 is a n a l l - p u r p o s e Also—Apiezon Oils—low va stop-cock grease for moder por pressures—very s t a b l e — ate v a c u u m use d o w n t o 1 0 1 ideal as v a p o r - d i f f u s i o n p u m p torr a n d a s o f t e n i n g point of fluids. 185°C. Apiezon Compound Q a T h e s e greases a r e resist putty-like, versatile, low cost ant to o r g a n i c solvents a n d sealant. will not leach o u t of g r o u n d Apiezon Waxes for more glass joints or stop-cocks. permanent vacuum joints. Write tor Bulletin 43-AC. Oil
Determination of Nitrogen in Vanadium Nitrides and Uranium Nitride (UN).
D. H. Bollman and D. M. Morti-
more
154
Correspondence Re:
"Criteria for Judging Acceptability of Analytical
Methods."
T. J. Farrell
156
Aids for Analytical Chemists Nonaqueous Electrochemical Cell Capable of Rigorous
JAMES G. BIDDLE CO.
Exclusion of Water and Oxygen.
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ANALYTICAL CHEMISTRY, VOL. 43, NO. 1, JANUARY 1971
© Copyright 1971 by the American Chemical Society
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