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The procedure is used to determine ethyl acrylatein ethyl acrylate- styrene copolymer emulsions. ORLANDO TWEET and W. K. MILLER, S. C. Johnson & Son, ...
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AC BRIEFS Highlights of the scientific a n d technical articles in this issue

Half Lives of Cesium-137 and Cesium-134 as Measured by Mass Spectrometry

Use of a Multichannel Analyzer for Electron Probe Microanalysis A 400-channel multichannel analyzer attached to an elec­ tron probe analyzer increases the versatility and de­ creases the time in many analyses. T h e multichannel ana­ lyzer is used in conjunction with the regular x-ray optics; one port of the electron probe is used for the multichan­ nel analyzer while the others are used for crystal spec­ trometers. Other applications are discussed. L. S. BIRKS and A . P. BATT, U . S. N a v a l W a s h i n g t o n 2 5 , D. C .

Research

Mass rates 30.35 Cs18*. being

spectrometric measurements of radioactive decay over a period of lVa years indicates a half life of ± 0.38 years for Cs1*7 and 2.046 ± 0.004 years for Preliminary precision values are given; the work is continued.

L. A . DIETZ, C . F. P A C H U C K I , and G . A . L A N D , G e n e r a l Elec­ tric C o . , Schenectady, Ν . Υ .

Laboratory,

A n a l . C h e m . 35, 778 ( 1 9 6 3 )

Oxygen Flask Method for the Assay of T r i t i u m - , Carbon-14-, and Sulfur-35-Labeled Compounds The combustion flask is sealed before ignition and not opened until preparation of the counting sample is com­ pleted, minimizing errors. T h e activity is measured by liquid scintillation counting. H . E. DOBBS, United Kingdom A t o m i c Energy Research Establish­ ment, W a n t a g e , Berks, England

A n a l . C h e m . 35, 797 ( 1 9 6 3 )

Volumetric and Spectrophotometric Determination of Oxamide in NitrocelluloseBase Propellants The methods involve hydrolysis of the nitrocellulose and oxamide with 10% sodium hydroxide solution, steam distillation, and determination of the ammonia produced. A correction is made for the amount of ammonia pro­ duced by the reaction of nitrocellulose with alkali. J . B. A P A T O F F , J O S E P H C O H E N , and G E O R G E Frankford Arsenal, Philadelphia 3 7 , Pa.

NORWITZ,

A n a l . C h e m . 35, 800 ( 1 9 6 3 )

A n a l . C h e m . 35, 783 ( 1 9 6 3 )

Statistical Aspects of Liquid Scintillation Counting by Internal Standard Technique. Single Isotope Equations are given i'or determining the percentage error in a calculated rate, corrected for counting efficiency. The equations are evaluated for a range of counting efficien­ cies, activities of internal standard, and counting times before and after internal standard addition. R. J . H E R B E R G , Lilly Research Laboratories, Indianapolis 6, I n d .

Determination of Mixtures of Hydrazine and 1, 1-Dimethylhydrazine ( U D M H ) . Potentiometric and Spectrophotometric End Point Detection Modifications in a previously presented method have re­ sulted in improved reproducibility and reduced inherent errors. T h e reproducibility for the U D M H titration of a 50-50 mixture has been reduced from a relative standard deviation of 4.4% t o 0.93% and 0.69% for the potentio­ metric and photometric detection techniques, respectively. E. A . BURNS and E. A . L A W L E R , M e n l o Park, C a l i f .

Neutron activation of oxygen in gallium arsenide is car­ ried out using the 0™(T, n)Fls reaction with the tritons produced by the Win, 2')He 4 reaction. T h e best sensi­ tivity is about 7 X 1CT9 gram of oxygen in gallium arsenide. R. F. BAILEY and D. A . ROSS, R C A Laboratories, Princeton, N . J .

I n this study color quenching is correlated with concen­ tration and wavelength absorption maximum of the quenching material for t h e liquid scintillator system of carbon-14 in dioxane scintillator. I n any S3'stem the pre­ dicted color quenching with the observed total quench­ ing permits calculation of the amount of chemical quench­ ing within t h e system. H . H . ROSS and R. E. YIERICK, O a k Ridge Institute of Nuclear Studies, O a k Ridge, Tenn. A n a l . C h e m . 35, 7 9 4 ( 1 9 6 3 )

Institute,

Spectrophotometric Determination of Neptunium Using 1.23-Micron Sexivalent Absorption Peak At ambient temperatures neptunium is oxidized by sexi­ valent chromium t o the sexivalent state with an absorp­ tion peak at 1.23 μ. T h e absorption peak conforms to Beer's law. T h e method has a relative standard de\dation of ± 5 % at 3 grams per liter. C . A . C O L V I N , G e n e r a l Electric C o . , Richland, W a s h . A n a l . C h e m . 35, 806 ( 1 9 6 3 )

A n a l . C h e m . 35, 791 ( 1 9 6 3 )

Quantitative Interpretation of Color Quenching in Liquid Scintillator Systems

Research

A n a l . C h e m . 35, 802 ( 1 9 6 3 )

A n a l . C h e m . 35, 786 ( 1 9 6 3 )

Determination of Oxygen in Gallium Arsenide by Neutron Activation Analysis

Stanford

A New Spectrophotometric Method for the Determination of Microgram Amounts of Selenium The oxidation of phenylhydrazine p-sulfonic acid by selenious acid was studied. T h e azo dyestuff, formed when the diazonium oxidation product is coupled with 1-naphthylamine, was measured at 520 ταμ to determine trace amounts of selenium. Acidity, reagent concentra­ tion, and reaction rates were studied for both the oxida­ tion and coupling processes. G . F. K I R K B R I G H T Charlottesville, V a .

and J .

Η.

Υ Ο Ε , University

of

Virginia,

A n a l . C h e m . 35, 808 ( 1 9 6 3 )

V O L . 3 5 , N O . 7 , JUNE 1 9 6 3



9 A

BRIEFS! Cation Exchange Separation of Lead Lead is separated from most metal cations by elution from a hydrogen-form cation exchange column with 0.6M hydrobromic acid. Special precautions are taken t o avoid interference from bismuth, cadmium, and tin. J . S. FRITZ and R. G . G R E E N E , Iowa

Iowa

State

University,

Ames,

A n a l . C h e m . 35, 811 ( 1 9 6 3 )

Analysis of Pesticide Residues Using Microcoulometric Temperature-Programmed Gas Chromatography A commercial instrument was modified to include temperature programming and a dual detector system. T h e advantages of these modifications in pesticide residue analysis are illustrated by chromatograms. W . A . B O S I N , The Pillsbury C o . , Minneapolis 14, M i n n . A n a l . C h e m . 35, 833 ( 1 9 6 3 )

Colorimetric Reagents for the Analysis of Aluminum Alkyls Triphenylmethane-type indicators are used t o determine the equivalence pointu in the titration of aluminum alkyls with electron-doner reagents such as aromatic amines, ether, and alcohols. Various reagents which form colored complexes with aluminum alkyls are reported. D. F. H A G E N City, Okla.

and W . D. LESLIE, Continental

O i l C o . , Ponca

A n a l . C h e m . 35, 814 ( 1 9 6 3 )

Gas Chromatographic Behavior of C , - C , Saturated Alcohols and W a t e r on Polyethylene Glycol Substrate. Effect of Solid Support Treatment Twelve columns coated with approximately 20% polyethylene glycol-400 were used. The treatment affected the activity of the solute and resulted in large variations of specific retention volumes, distribution coefficients, and heats of solution. P A U L U R O N E , University of C o l o r a d o , Boulder, C o l o . , and R. L. PECSOK, University of C a l i f o r n i a , Los Angeles 24, C a l i f . A n a l . C h e m . 35, 837 ( 1 9 6 3 )

Infrared Spectra-Structure Correlation Study of Vanadium-Oxygen Compounds A spectra-structure ccrrelation chart is given which covers various compound classes—e.g., deçà-, hexa-, meta-, pyro-, and orthovanadates, vanadyl salts, and oxides. Spectral data and interpretations are summarized in this paper. L. D. F R E D E R I C K S O N , Jr., Spectran Laboratories, Inc., Denver, C o l o . , and D. H . H A U S E N , Union C a r b i d e Nuclear C o . , G r a n d Junction, C o l o . A n a l . C h e m . 35, 818 ( 1 9 6 3 )

A Rapid Combustion Method f o r Nitrogen Determination Utilizing Gas Chromatography The method is based on sample combustion in a helium atmosphere and conversion of the nitrogen oxides to elemental nitrogen. Other combustion products are absorbed before reaching the chromatographic column. T h e nitrogen is passed through a 5-A Molecular Sieve column and detected by a thermal conductivity detector. M . L. P A R S O N S , S. N . P E N N I N G T O N , and J . M . Kansas State C o l l e g e of Pittsburg, Pittsburg, Kan.

WALKER,

A n a l . C h e m . 35, 842 ( 1 9 6 3 )

Selective Spectrophotometric Method for the Determination of p-Aminophenol The method involves oxidation of p-aminophenol by cerium(IV) perchlora;e in 3F perchloric acid t o form a purple compound. T h e procedure gives t h e determination of 0.50 to 5.0 mg. per ml. of p-aminophenol, and 0.140 to 2.10 mg. per ml. of cerium(IV) with a relative error of about 1.5%. G . G . G U I L B A U L T , U. S. A r m y Chemical ment Laboratories, Edgewood Arsenal, M d .

Research & Develop-

A n a l . C h e m . 35, 828 ( 1 9 6 3 )

Determination of Trace Quantities of Uranium by Neutron Activation Analysis The method is based on the reaction TJ2SS(n, •y)\]:ss' and measurement of the 7.4-k.e.v. line of U230. Chemical separation is achieved through selective extraction of uranium from sulfuric acid medium with tri-n-octylamine in kerosine. T h e method is applied to uranium in clover, human urine, and aluminum. DIRK D E C A T , B E N J A M I N V A N Z A N T E N , and G E O R G E LIAERT, C e n t r e d'Etude de l'Energie Nucléaire, M o l , Belgium

LE-

A n a l . C h e m . 35, 845 ( 1 9 6 3 )

Titrimetric Determination of Boron in Boron Suicides. An Evaluation of Separation Procedures Second-derivative potentiometric titration was used t o evaluate procedures for the separation and determination of boron. Accuracy on synthetic samples was 1 part per thousand. Precision of each of the three methods evaluated was 2 parts per thousand. A . J . F R A N K , Allis-Chalmers Wis.

Manufacturing

C o . , Milwaukee

I,

Anal. Chem. 35, 830 (1963)

Apparatus for Extraction of Gases for Injection into the Gas Chromatograph. Application to Oxygen and Nitrogen in Jet Fuel and Blood An instrument is described which permits anaerobic sampling, releasing of the gases, and eventual injection of solvent free gases into a gas chromatograph. T h e method is applied to oxygen and nitrogen in jet fuel and blood. SAMUEL NATELSON N e w York, Ν . Υ .

and R. L. STELLATE, Roosevelt

Hospital,

A n a l . C h e m . 35, 847 ( 1 9 6 3 )

VOL. 3 5 , N O . 7 , JUNE 1 9 6 3



11

A

BRIEFS Determination of Residual Monomer in Polymer Emulsions by Rapid Distillation and Gas Chromatography The monomer content is calculated by measuring the peak area ratio of monomer to the toluene internal standard and referring to a calibration curve. T h e procedure is used t o determine ethyl acrylate in ethyl acrylatestyrene copolymer emulsions. O R L A N D O T W E E T and W . K. M I L L E R , S. C . Johnson & Son, Inc., Racine, W i s .

Controlled-Potential Coulometric Determination of Indium The method involves the coulometric reduction of In(III) t o I n ( H g ) at - 0 . 6 6 volt vs. S.C.E. in 1M KC10.25M HC1 medium. T h e relative standard deviation is about 0.1% and the relative error is 0.1 t o 0.2% at the 5-mg. level. W . R. M O U N T C A S T L E , Jr., W . D. SHULTS, and P. F. T H O M A S O N , Oalc Ridge N a t i o n a l Laboratory, O a k Ridge, Tenn. A n a l . C h e m . 35, 871

(1963)

A n a l . C h e m . 3 5 , 852 ( 1 9 6 3 )

Determination of Traces of Organic Acids in Small Samples. Gas Liquid Chromatography of the Total Concentrate The acids are isolated by steam distillation, and concentrated in a manner to rend them suitable for analysis by gas liquid chromatography. Application of batch distillation theory to estimation of maximum theoretical losses of organic acids by volatilization is described. V. M . RIDDLE, Spreckels Sugar C o . , W o o d l a n d , C a l i f .

Ground plant direct flame The method methods in a tories.

material suspended in liquid is used for photometric determination of potassium. is evaluated by comparison with other collaborative study involving other labora-

J . L. M A S O N , C a n a d a B. C , C a n a d a

Department of Agriculture, Summerland,

A n a l . C h e m . 35, 874 ( 1 9 6 3 )

A n a l . C h e m . 35, 853

(1963)

Indirect Polarographic Determination of Acids The method depends on the measurement of diffusion currents limited by the acid consumed in the electrode reaction: quinone +2e + 2H+ = hydroquinone. T h e procedure was applied t o hydrogen ion and aluminum ion, alone and in mixtures. Extension of the method to other species which react with hydroxyl ion is suggested. J . C . A B B O T T and J . W . C O L L A T , The O h i o State Columbus, O h i o

Flame Photometric Determination of Potassium in Unashed Plant Leaves

University,

A n a l . C h e m . 35, 8 5 9 ( 1 9 6 3 )

Flame Spectrophotometry of Calcium with Reversed Oxyacetylene Flame. Application to Serum and Urine In this method a direct oxyacetylene sprayer burner is modified to use acetylene as the spraying gas. The influence of various ions and protein précipitants on t h e calcium emission at 422.7 ταμ is discussed. Normal serum calcium value with this method is 5.15 ± 0.25 meq. per liter ( ± 2 std. dev.). H . F. L O K E N , J . S. TEAL, and E U G E N E EISENBERG, University of C a l i f o r n i a School of M e d i c i n e , San Francisco, C a l i f . A n a l . C h e m . 35, 875 ( 1 9 6 3 )

Determination of W a t e r below 10 p.p.m. in Benzene and Related Solvents, Using Coulometrically Generated Iodine

Studies in the Structure of Organic Peroxides

Water in benzene and related chemicals can be determined below 10 p.p.m. using iodine coulometrically generated from K I dissolved in a solvent containing pyridine, formamide, and sulfur dioxide. E n d point is by dead stop. Special techniques for handling samples are discussed. R. F. S W E N S E N and D. A . K E Y W O R T H , Universal O i l Products C o . , Des Plaines, I I I .

Peroxy acids are shown to exist in solution as intramolecularly hydrogen-bonded monomers containing a puckered five-membered ring. In the solid state, peroxy acids exist as dimers. Diacyl peroxides and ieri-butyl peroxy esters are also included in this study. D A N I E L S W E R N A N D L. S. SILBERT, Eastern Regional Laboratory, Philadelphia 18, Pa.

Research

A n a l . C h e m . 35, 880 ( 1 9 6 3 )

A n a l . C h e m . 35, 863 ( 1 9 6 3 )

Gas Chromatography of Organic Peroxides Experimental Evaluation of Liquid-Junction Potential Of four redox systems studied the 4,7-DMPhFe(II), 4,7D M P h F e ( I I I ) couple proved the best for evaluating liquid-junction potentials. T h e reliability of this tech­ nique in this study appears to be about 5 mv. I. V . N E L S O N Lawrence, Kan.

and R. T.

IWAMOTO.

University

of

Kansas,

A n a l . C h e m . 35, 8 6 7 ( 1 9 6 3 )

Organic peroxides are determined using an internal stand­ ard technique. 2,5-Dimethyl-2,5-di(ieri-butyIperoxy)hexane, ieri-butyl peracetate, and 2,5-dimethyl-2,5-di(ieri-butylperoxy)-3-hexyne can be determined with a relative error of ± 1 . 0 % , while high purity di-ieri-butyl peroxide is determined with a relative standard deviation of ± 0 . 3 % . S. W . B U K A T A , L. L. Z A B R O C K I , and M . F. W a l l a c e & Tiernan, Inc., Buffalo 5, Ν . Υ .

McLAUGHLIN,

A n a l . C h e m . 35, 885 ( 1 9 6 3 )

VOL. 3 5 , N O . 7 , JUNE 1 9 6 3



13 A

BRIEFS Safe Handling and Storage of Organic Peroxides in the Laboratory

No.

D a t a from described tests is tabulated to indicate the safety characteristics of some organic peroxides. Methods are given for the detection and removal of residual or trace quantities of peroxides as well as precautionary measures to be followed in their purification.

37

in the

ADVANCES IN CHEMISTRY

D. C. NOLLER and D. J. BOLTON, Wallace & Tiernan, Inc., Buffalo 5, Ν. Υ. Anal. Chem. 35, 887 (1963)

SERIES

Controlled-Potential Coulometric Determination of Hydrogen Peroxide Hydrogen peroxide is oxidized at a platinum electrode at +0.93 volt vs. S.C.E. in a supporting electrolyte of \M sulfuric acid. In the range of 0.1 to 2 mg. of hydrogen peroxide in a solution volume of less than 5 ml., the rela­ tive standard deviation of the determination is ± 0 . 1 % . J . E. HARRAR, University of California, Livermore, Calif. Anal. Chem. 35, 893 (1963)

Galvanic Monitoring of Ozone in Air The method uses a galvanic cell with a platinum cathode, a carbon anode, and a neutral buffered solution of halide as the electrolyte. No calibration with a standardized source of ozone is needed. PAUL HERSCH and RUDOLF DEURINGER, Beckman Instruments, Inc., Fullerton, Calif. Anal. Chem. 35, 897 (1963)

Stabilized Diazoniium Salts as Analytical Reagents for the Determination of Air-Borne Phenols and Amines Analytical procedures have been developed for 24 of the compounds. The most suitable conditions of p H and the optimum diazo salt in relation to sensitivity and color stability were determined. Precision and accuracy data of the methods are given. G. A. LUGG, Australian Defence Scientific Service, Maribyrnong, Victoria, Australia Anal. Chem. 35, 899 (1963)

Cathodic Action of the Uranyl-Lactate Complex a t the Dropping Mercury Electrode The polarographic behavior of the complex of uranium with lactic acid has been studied. The complex forms and electrode reaction in various ranges of p H value and concentration of complexing agent are suggested. TSAI-TEH LAI and I3I-CHENG versity, Tainan, Taiwan, China

WANG,

Cheng

Kung

Uni­

Anal. Chem. 35, 905 (1963)

REACTIONS OF COORDINATED LIGANDS AND HOMOGENEOUS CATALYSIS The 18 papers in this volume explore an area which has recently taken on renewed life. All given before the Sym­ posium on Homogeneous Catalysis and Reactions of Coordinated Ligands held by the Division of Inorganic Chemistry at the 141st ACS National Meeting in March 1962, they represent timely material. Coordination chemists now are paying more attention to the ligands. Major developments which spotlight this area are (1) biochemical research which reveals the role of coordinated metal ions in biochemical synthesis and in energy storage and transfer, (2) the search for polymers which can withstand high temperatures, in turn, uncover­ ing interesting ligand reactions, and (3) the discovery of the oxo- and the Ziegler-Natta catalytic syntheses which focus interest on coordination compounds as reaction intermediates. Further investigation into ligand reactions is bound to be fruitful. If you are working anywhere in this field, you will need this volume as part of your literature. 255 pages.

Paper bound.

Price: $7.00

Simultaneous Determination of Hypobromite, Bromite, and Brornate Using Ammonium Sulfate Ammonium reacts selectively with hypobromite, but not with bromite, and is used to estimate hypobromite in the presence of bromite. The reaction is quantitative between p H 7.5 to 9.5. The influence of various salts is discounted. M. H. HASHM1 and Α. Α . ΑΥΑΖ, C.S.I.R., Lahore, West Pakistan

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from:

Special Issues Sales/American Chemical Society 1155 Sixteenth Street, N.W./Washington 6, D. C.

Anal. Chem. 35, 908 (1963) VOL. 35, NO. 7, JUNE 1963



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