Highlights
of Articles in This Issue
A Kinetic Method for the Determination of Fluoride in the Parts-pea-Billion Range
Gas Chromatographic Estimation of Occluded Solvents in Adhesive Tape by Periodic Introduction Method
Trace amounts of fluoride can be determined very aensitively by its strong inhibiting action on the catalyst in the zirconium catalyzed reaction between perborate and iodide.
A new direct method for estimating occluded sol\-ents in coated polymeric materials has been developed by means of gas chromatography.
DIETER KLOCKOW, HEINER LUDWIG, a n d MIGUEL A. GIRAUDO, Chemical Laboratory, University of Freiburg, Freiburg Br., German Federal Republic
M l K I O SUZUKI, Research Department, Nichiban Company, Nerima-ku, Tokyo, Japan, a n d S H I N TSUGE and TSUGIO TAKEUCHI, Department of Synthetic Chemistry, Faculty of Engineering, Nagoya University, Nagoya, Japan
Anal. Chem., 42, 1682 (1970)
Anal. Chern., 42, 1705 (1970)
Determination of Sodium Nitrate in Sodium Nitrite by Selective Ion Electrode Measurement Small amounts of sodium nitrate in sodium nitrite were measured using a nitrate selective ion electrode. Precision (95% confidence) was +0.02% a t the O.ZOC/c nitrate concentration level. DOUGLAS G. GEHRING, WILLIAM A. DIPPEL, a n d ROBERT S. BOUCHER, Eastern Laboratory, Explosives Department, E. 1. d u Pont d e N e m o u r s & Company, Gibbstown, N. J .
08027 Anal Chem.,
42,1686 (1970)
Rate Measurements of Highly Variable Gas Evolution with a Mass Flowmeter
Automatic Data Recording of Unsaturation by Quantitative Hydrogenation The automatic and continuous recording of the titrant uptake during hydrogenation of olefins using the Brown catalytic hydrogenation technique offers quicker data interpretation and a uniform permanent record. J. J . SZAKASITS, Houston Research Laboratory, Shell Oil Company, P. 0. Box 100, Deer Park, Texas 77536 Anal. Chern., 42, 1708 (1 970)
Nitrogen Adsorption on Chemicafly Modified Silica Gels
A mass flowmeter-recorder combination to measure steadystate gas flow is satisfactory for measuring highly variable rates of gas evolution provided necessary corrections are made. Response is rapid and precision high. ISAO MATSUZAKI, ROBERT E . ALEXANDER, a n d HERMAN A. LIEBHAFSKY, D e p a r t m e n t of Chemistry, Texas A & M University, College Station, Texas 77843 Anal. Chem., 42, 1690 (1970)
Use of the Molecular Orbital Theory of Charge Transfer Spectra in Searching for Multiple Charge Transfer Bands of the Pi Complexes of 2,3-Dichloro-5,6-Dicyano-p-Benzoquinone Many organic T complexes frequently exhibit two charge transfer spectral bands. The Dewar molecular orbital theory of charge transfer spectra can be used to calculate locations of both the lowest energy and the higher energy bands. GEORGE H. SCHENK a n d PETER A. FRYER, Department of Chemistry, Wayne S t a t e University, Detroit, Mich. 48202
Silica gels modified by attachment of organic groups were studied to determine changes in properties derivable from adsorption isotherms. Site energy distribution profiles showed increased uniformity of surface, and average adsorption energy decreased. JAMES B. SORRELL a n d ROBERT ROWAN, JR., New Mexico S t a t e University, Las Cruces, N. M. Anal. Chem., 42, 1712 (1970)
Modified Silica Gel Adsorbents in Gas-Solid Chromatography Chemicaily modified silica gels. used as adsorbents in yassolid chromatography, showed marked improvements in column efficiency, better resolution, and reduction of tailing. ROBERT ROWAN, JR., a n d JAMES E. SORRELL, Departm e n t of Chemistry, New Mexico State University, Las Cruces, N. M . 88001 Anal. Chem., 42, 1716 (1970)
Anal. Chem., 42, 1694 (1970)
Pyrolysis Gas Chromatographic Determination of Arylsuifonic Acids and Salts
Elutive Displacement of Precipitate Formed during Electromigration of Ions The elution phenomenon during electromigration is treated theoretically and examples are given for the v a y the method can be put in practice.
Sulfonic acids, upon pyrolysis, yield sulfur dioxide and the parent hydrocarbon. Sulfur dioxide and, for some compounds, the parent hydrocarbon can be measured quantitatively for a wide range of sample sizes.
JORIS DEMAN, Kliniek v o o r Radiotherapie en Kerngeneeskunde, Akademisch Ziekenhuis, Gent, Belgiuni
SlDNEY SlGGlA and LEE R. WHITLOCK, University of Massachusetts, A m h e r s t , Mass. 01002
Anal. Chem., 42, 1699 (1970)
Anal. Chem., 42, 1719 (1970)
ANALYTICAL CHEMISTRY, VOL. 42, NO. 14, DECEMBER 1970
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Fluorometric Measurement of Aromatic Hydrocarbon Mixtures after the Biels-Alder Reaction of Anthracene
Determination of Medazepam (Nobrium), Diazepam (Valium) and Their Major Biotransformation Products in Blood and Urine by Electron Capture Gas-Liquid Chromatography A sensitive and specific electron capture gas chromatographic assay was developed for the determination of medazepam and diazepam and their major metabolites in blood and urine \Tith a sensitivity limit of 0.02 to 0.04 F g 0:' compoundiml. J . ARTHUR F. DE SlLVA and CARL V . PUGLlSl, Departm e n t of Clinical Pharmacology, Hoffman-La Roche lnc., Nutley, N . J . 07110 Anal. Chem., 42, 1725 (1970)
Quantitative Analysis of Triglyceride Mixtures by Mass Spectrometry
A rapid and sensitive mass spectrometric method has been
The Diels-Alder adduct of maleic anhydride and anthracene is not fluorescent (although it is phosphorescent). This permits the fluorometric measurement of some aromatic hydrocarbons. GEORGE H. SCHENK and DONALD R. WlRZ, Department of Chemistry, Wayne State University, Detroit, Mich. 48202 Anal. Chem., 42, 1754 (1970)
Gas-Liquid Chromatographic Betermination of Chlorpheniramine in Blood Plasma Flame ionization detectors have adequate sensitirity when coupled with selective and efficient extracrion methods, modern column technology and a semi-programmed mode of operation.
developed for determining the molecular weight diatribution of triglyceride mixtures. Triglyceride composition and structure are thereby deduced.
EDWARD JOWNLEY, ISIDORO PEREZ, and PETER KABASAKALIAN, Research and Development Division, Schering Corp., Bloomfield, N. J . 07003
RONALD A. HUES, Northern Regional Research Laboratory, Peoria, 111. 61604 Anal. Chem., 42, 1736 (1970)
Anal. Chem., 42, 1759 (1970)
Diffusion Coefficients of Ferri- and Ferrocyanide Ions in Aqueous Media, Using Twin-Electrode Thin-Layer EBect roc hem istry
A critical evaluation of this steady-state amperometriccoulometric method is made. D-values found for ferri- and ferrocyanide in 1 , O O X KC1 are 0.726(+-0.011) x 10-' and
0.667(t0.014) x lom6cm'/sec., respectively, x i t h essentially identical values in 0.1Oilf KC1. S. J . KONOPKA and BRUCE MCDUFFIE, Department of Chemistry, State University of New York a t Binghamton, Binghamton, N. Y. 13901 Anal. Chem., 42, 1741 (1970)
Diffusion Controlled Polarographic Catalytic Hydrogen (BrdiEka) Currents in Systems Containing Cobait(l!), Cysteine-Like Compounds, and Alkaline Buffers Catalytic Brdicka currents obtained with cysteine-like compounds become diffusion controlled when the molar ratio of the sulfhydryl compounds t o cobalt(I1) attains a certain value which is close to 1. 1. M. KOLTHOFF, School of Chemistry, University of Minnesota, Minneapolis, Minn. 55455, and P. MADER, Departm e n t of Biophysics and Plant Physiology, University of Agriculture, Prague 6, Czechoslovakia
Anal. Chem., 42, 1762 (1970)
Trace Analysis of Pesticides Using Cholinesterase from Human Serum, Rat Liver, Electric Eel, Bean Leaf Beetle, and White Fringe Beetle
Method and Apparatus for Determining Helium Content of Gas Mixtures
A method and apparatus are presented for determining the helium content of gaseous mixtures. Twenty or more analyses with a standard deyiation of +O 04% can be made in eight hours. DAVID E. EMERSON and RlCHARD L. KAPLAN, Division of Helium, Bureau of Mines, U. S. Department of t h e Interior, Amarillo, Texas 79106 Anal. Chem., 42, 1746 (1970)
I n this present study, the inhibitory effects of 14 different pesticides including organophosphorus compounds, carbamates, and chlorinated hydrocarbons on cholinesterase from human serum is reported. M . H. SADAR, S . S. KUAN, and G. G. GUILBAULT, Departm e n t of Chemistry, Louisiana State University in New Orleans, New Orleans, La. 70122 Anal. Chem., 42, 1770 (1970)
Use of Selective ion Exchange Paper in X-Way Spectrography and Neutron Activation. Application to the Determination of Gold
Effect of Matrix Material on Laser-Induced Elemental Spectral Emission
A new collection procedure prorides a simple means of preconcentrating trace elements from large samples. The determination of gold in the ppm and ppb ranges is given as an example. THOMAS E. GREEN, STEPHEN L. LAW, and W l L L l A M J . CAMPBELL, U. S. Department of t h e Interior, Bureau of Mines, College Park Metallurgy Research Center, College Park, M d . 20740 Anal. Chem., 42, 1749 (1970)
The magnitude of suppression of spectral emission of silver and magnesium by organic and inorganic material with laser microprobe sampling and excitation was studied. KENNETH W. MARICH, PETER W. CARR, WILLIAM J . TREYTL, and DAVID GLlCK, Division of Histochemistry, Department of Pathology, Stanford University School of Medicine, Stanford, Calif. 94305 Anal. Chem., 42, 1775 (1 970)
ANALYTICAL CHEMISTRY, VOL. 42, NO. 14, DECEMBER 1970
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Biennial_publication of the ACS Committee on Profess7onZJ77aTniing Covers the universities and colleges in the United States and Canada known to offer an organized curriculum !eading to the doctoral degree in chemistry, biochemistry, chemical engineering, and pharmaceutical or medicinal chemistry. The guide to graduate schools, research, and personnel in these areas. 201 Departments of Chemistry 165 Departments offering Biochemistry 106 Departments of Chemical Engineering 29 Departments of Pharmaceutical or Medicinal Chemistry While you may get peaks from recent imitations of Porapak, you get this degree of separation onlyfrom the original porous polymer GC column packingPorapak, made by Waters. C)f the eight different Porapaks (two with surface silanization for deactivation of labile sites), Porapak "T",used in this separation, has the highest polarity and the greatest water-retention capability. Note that the water peak occurs at 2 minutes, well after the formaldehyde peak. And the entire analysis takes only 3 l h minutes. Check these advantages of the Porapak materials: e Effective separation of aqueous samples; 0 No need for liquid coating, therefore no bleed; Large surface areas; * Rapid overload recovery; * No adsorption of polar compounds; e Most Porapak materials stable to 250°C; e Easy handiing for column-packing efficiency. We have a new catalog covering our full line of column-packing materialsfor gas and liquid chromatography. Write for it, Waters Associates, Inc., 61 Fountain St., Framingham, Mass. 01 701.
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ANALYTICAL CHEMISTRY, VOL. 32, NO. 14, DECEMBER 1990
Lists 2807 full- and part-time staff members, each with outline of career, teaching and research specialties, and list of publications for the past two or five years. Statistical data on departments include number of Ph.D. degrees conferred during the previous two years, number of staff members, and number of postdoctoral appointments. Other listings include interdisciplinary programs and doctoral theses accepted during previous two years. 1213 pp. with index of names paper bound (1970) $10.00 postpaid in US., plus 50 cents Canada and Pan America, plus 75 cents foreign. Order from:
Special lssue Sales Aknerican Chemical Society 1155 Sixteenth St., N.W. Washington, D. C. 20036
An Electrode for Determination of Amino Acids An electrode for the determination of amino acids is descryhed n-hich is made with immobilized L-amino acid-oxidase. The electlode detects SH,' ions formed in the enzyme catalyzed oxidation of the amino acid.
G. G. GUILBAULT a n d E. HRABANKOVA, Department of Chemistry, Louisiana S t a t e University in New Orleans, New Orleans, La. 70122 Anal. Chem., 42, 1779 (1970)
Separation and Determination of Aromatic Sulfonates by Ion Exchange Column Chromatography Described is the w e of a polyalkylene amine ion exchange resin in mixed sol1 ents t o effect separation of aromatic SUIfonates The separation of phenol sulfonates. amino-sulfonates, and diphenyl sulfonates is described RUDOLPH H. STEHL, Analytical Laboratones, The Dow Chemical Company, Midland, Mich. 48540 Anal. Chem., 42, 1802 (1970)
Gas-Liquid Chromatographic Study of Selected Derivatives of 2-lmidazolidinone The effect of pH on reactions occurring in aqueous solutions of methoxymethyl methyl imidazolidinone was investigated by GLC. Low p H increases the rate of conversion t o the final product, methylenebis-l-[3-methyl-2-imidazolidinone) I. AUSTIN 1. BULLOCK a n d STANLEY P. ROWLAND, Southern Regional Research Laboratory, P. 0. Box 19587, New Orleans, La. 70119 Anal. Chem., 42 1783 (1970)
Separations of Enantiomeric Derivatives of Amines and Amino Acids by Adsorption Chromatography Chromatographically active and inactive eolid forms of the ureide of L-raline isopropyl ester are described as well as the behavior below the melting point of two other opticallyactive stationary phases. J . A, CORBIN a n d L. B. ROGERS, Department of Chemistry, Purdue University, Lafayette, Ind. 4790'
Anal. Chem., 42, 1785 (1970)
Separation and Characterization of Methylethylnaphthalene Isomers by chromatographic and Spectrometric Methods
Determination of the Number and the Nature of the End Groups of Poly(Winyl Chloride) Optimum conditions of complete reaction of PVC and model compounds nith lithium aluminum hydride have been established One unsaturated end group, l-chloro1 inyl, seems to be present in each PTC molecule. MARC CARREGA, CLAUDE BONNEBAT, a n d GEORGES ZEDNIK, PBchiney-Saint Gobain, Centre de Recherches de la Cro/x-de-Berny, 182, Avenue Aristide Briand, 92 Antony, France Anal. Chem., 42, 1807 (1970)
Spectrophotometric Submicrodetermination ob Nitrites after Double Extraction of the Azo Compound Produced An extraction followed by a retrograde extraction with different pH ranges is proposed in order to improve the optimum concentratioii range for a classical method for spectrophotometric determination of nitrite. G. R. MACCHI a n d €3. S. CESCON, Osservatorio Geofisico Sperimentale, Viale Romolo Gessi, 4 Trieste, Italy Anal. Chem., 42, 1809 (1970)
Thirteen of the fourteen possible methylethylnaphthalene isomers were characteiized in the synthetic mixtures using instrumental methods of analysis. The sterically hindered 1-methyl-S-ethylnaphthalene TT-as not found. J. M. DUSWALT a n d T. J. MAYER, Sun @il Company, Marcus Hook, Pa. 19061 Anal. Chem., 42, 1789 (1970)
Chemiluminescent Measurement of Atmosplheric Ozone. Response Characteristics and Operating Variables The chemiluminescent reaction of ozone with a dye compound adsorbed on silica gel has previously x e n used to monitor ozone copcentration in the upper atmosphere. J . A. HODGESON, K. J . KROST, A. E. O'KEEFFE, a n d R. K . STEVENS, U . S. Department of Health, Education, a n d Welfare, Public Health Service, Consumer Protection a n d Environmental Health Service, National Air Pollution Control Administration, Division of Chemistry a n d Physics, 3820 Merton Drive, Raleigh, N. C. 27609
Anal. Chem., 42, 1795 (1970)
Combination of Gas Chromatography and Chemical Ionization Mass Spectrometry
A Bendix T O F mass spectrometer has been combined with a gas chroniatograph to give a GC-R/IS system in which the carrier gas of the chromatograph also serves as the chemical ionization reactant gas. DONALD M. SCHOENGOLD a n d BURNABY MUNSON, Department of Chemistry, University of Delaware, Newark, Del. 19711 Anal. Chem., 42, 1811 (1970)
Determination of Blood Ammonia by Derivative Spectrometry Total blood ammonia was determined by liberating ammonia gas from an alkalinized supernatant sample in a closed cell and measuring the ammonia partial pressure using a second derivative spectrometer. ROBERT N. HAGER, JR., DAVID R. CLARKSON, a n d JOHN SAVORY, Department of Aerospace Engineering, University of Florida, Gainesville, Fla. Anal. Chem., 42, 1813 (1970)
ANALYTICAL CHEMISTRY, VOL. 42, NO. 14, DECEMBER 1970
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Analysis of p,p'-Bis-(Chlorocyclohexyl) Sulfides Mixtures of bis-(chloiocyclohexyl) monosulfide and polysulfides can be analyzed rapidly by IR spectrophotometry. Analysis for monosulfide by titration of hydrolyzed chlorine and semi-quantitative analysis of mixtures by thin-layer chromatography are described. DUNCAN A. MACKILLOP, Dunlop Researcb Center, Sheridan Park, Ontario, Canada Anal. Chem., 42, 1815 (1970)
Simple, Rapid, Gravimetric Method for the Estimation of Phenylphosphine and
Determination of Fluoride in Silicate Rocks without Separation of Aluminum Using a Specific Ion Electrode
d technique for potential measurement of fluoride in solutions containing 0.02 to 0.4 ppm F is described. Aluminum interfeience is controlled v i t h 0.1X sodium citrate. BLANCHE L. INGRAM, U. S. Geological Survey, Washing ton, D. 6. Anal. Chem., 42, 1825 (1970)
Gas Chromatographic and Related Properties of the Alkaline Earth Chelates with 2,2,6,6-Tet ramet h ~ I - 3 ~Heptanedione 5-
Pentaphenylcyclopentaphosphine Dilute solutions of phenylphosphine and pentaphenylcyclopentaphosphine quantitatively ieduce tellurium tetrachloride t o the metal and provide a rapid, convenient method for the analysis of these air sensitir-e compounds.
2,2,6.6-Tetramethyl-3,~-heptanedion.ato chelates of calcium
M. J. GALLAGHER a n d 1. D. JENKINS, Department of Organic Chemistry, University of New South .Wales, Kensington, N.S.W., 2033, Australia Anal. Chem., 42, 1817 (1970)
J. E. SCHWARBERG, R. E. SEVERS, a n d R. W. MOSHIER, Contribution from t h e Chemistry Research Laboratory, Aerospace Research Laboratories, ARC, Wright-Patterson Air Force Base, Ohio 45433 Anal. Chem., 42, 1828 (1970)
and strontium ha\ e considerably different gas chromatographic retention times. I n spite of these differences, it was possible to separate mixtures of the metal chelates.
Enhanced Stability of Sulfur Dioxide in Solution The stability of SO2 in solutions of tetrachloromercurate is enhanced by the addition of ethylenediamine tetraacetate. The decay rate is 1% per day and is independent of the concentration of SO2 because it follom a first order reaction.
Determination of Trace Elements In Glass by Activation Analysis Using Hydrated Antimony Pentoxide for Sodium Removal
F. P. SCARINGELLI, L. ELFERS, D. NORRIS a n d S. HOCHHEISER, Division of Chemistry a q d Physics, National Air
Methods are described for the determination by neutron activation analysis of ppm and ppb levels of some trace elements in glass containing 10% sodium.
Pollution Control Administration, Environmental Health Service, Public Health Service, U. S. Department of Health, Education, a n d Welfare, Cincinnati, Ohio 45226 Anal. Chem., 42, 1818 (1970)
THOMAS E. GILLS, WILLIAM F. MARLOW, a n d BARBARA A. THOMPSON, Analytical Chemistry Division, National Bureau of Standards, Washington, D. C. 20234 Anal. Chem., 42,1831 (1970)
Spark Source Mass Spectrometric Survey Analysis of Air Pollution Particulates
A survey for trace elements in air pollution particulates may be carried out with detection limits in the nanogram per cubic meter range. and precision estimated a t &30% standard deviation. R. BROWN a n d P. G. T . VOSSEN, Consultsnt Laboratory, AEI Scientific Apparatus Ltd., Manchester, England Anal. Chem., 42, 1820 (1970)
Cadmium(ll)/Cadmium(Mercury) Exchange and Double Layer Structure The application of two different criteria, that the RE and CL remain conztant and that the correct behavior of the Warburg impedance for solving the model of the electrode interphase be used. yield differing results. An alternative model of the electrode interphase is proposed. NOEL A. HAMPSON, Department of Chemistry, Loughborough University of Technology, Loughborough, Leicestershire, England a n d DAVID LARKIN, Department of Chemistry, The University of Texas a t Austin, Austin, Texas 78712 Anal. Chem., 42, 1823 (1970)
Determination of Tin in Copper-Base Alloys by Mossbauer Spectrometry The Mdssbauer spectrometric method was applied to the determination of tin in 5BB SRM copper-base alloys. The absorption intensity of Pn02 was measured US. p-Sn as an internal standard absorber.
P. A. PELLA a n d J. R, DEVOE, Institute for Materials Research, National Bureau of Standards, Washington, D. C. 20234 Anal. Chem., 42, 1833 (1970)
Analysis of Butyllithium and Butylsodium in the Presence of Alkoxides The effect of various alkoxides of lithium, sodium. and potassium in the determination of the activity of BuLi and BuKa compounds mas studied. R. R. TURNER, A. G. ALTENAU, a n d T. C. CHENG, The Firestone Tire a n d Rubber Company, Central Research Laboratories, Akron, Ohio 44317 Anal. Chem., 42, 1835 (1970)
ANALYTICAL C H E M I S T R Y , VOL. 42, NO. 14, D E C E M B E R 1970
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Complex Formation in Lead Oxalate Solutions
-1 solubility technique was used to characterize the complexes formed in lead oxalate solutions. Ionic strength and temperature effects are presented. The presence of two mononuclear species of lead oxalate is established. LEON N. KLATT, Department of Chemistry, University of Georgia, Athens, Ga. 3 0 6 0 1 Anal. Chem., 42, 1 8 3 7 ( 1 9 7 0 )
Microdetermination of Molybednum by Anodic Stripping at Constant Current Using the Hanging Mercury Drop Electrode The stripping method used for analyzing dilute Blo(V1) solutions gives a relative precision of &1.7% for lO-'M solutions and &5% for 5 x 10-E.lfsolutions. PHILIPPE LAGRANGE, and JEAN-PAUL SCHWING, Instit u t de Chimie, 1 rue Blaise Pascal, 67-Strasbourg, France Anal. Chem., 42, 1844 ( 1 9 7 0 )
High Resolution Field Ionization Mass Spectrometry of the Condensable Phase of Cigarette Smoke Field ionization is used to enhance the molecular ion intensities of the components of cigarette emoke condensate. The elemental composition of 56 ions in the field ionization mass spectra of this complex mixture is reported. J. B. FOREHAND a n d W. F. K U H N , Philip Morris, Inc., P. 0. Box 3D, Richmond, Va. 2 3 2 0 6 Anal. Chem., 42, 1 8 3 9 ( 1 9 7 0 )
Correspondence Quaternary Oxide Systems as Hosts for X-Ray Excited Optical Fluorescence Detection of Rare Earths in Nuclear Materials at the Part per Giga (Part per 109) Level ARTHUR P. D'SILVA, EDWARD L. DEKALB, and VELMER A. FASSEL, Institute for Atomic Research and Department of Chemistry, Iowa State University, Ames, Iowa 50010
Carbowax as Dispersant in Counting and Sizing of Small Alumina Particles Using a Coulter Counter
Anal. Chem., 42, 1846 ( 1 9 7 0 )
Carbowax-1500 is found to be the best of a series of dispersants used in sizing alumina with a Coulter Counter. The relative standard deviation of the measurements is improved by a factor of two in comparison to the best of the other dispersants used (Triton X-100).
Aids for Analytical Chemists I
ELMER C. LUPTON, JR. and PATRICIA A. SHELBY, Air Force Rocket Propulsion Laboratory, Edwards, Calif. 9 3 5 2 3 Anal. Chem., 42, 1841 ( 1 9 7 0 )
Simplified Laser Degradation Inlet System for Gas Chromatography WILLIAM T. RJSJAU and NICHOLAS E. VANDERBORGH, Department of Chemistry, T h e University of New Mexico, Albuquerque, N. M. 871 06
Rapid Method of Determining First-Order IRate Constants from Experimental Data
Anal. Chem., 42, 1 8 4 8 ( 1 9 7 0 )
-4 new graphical method of determining first-order rate constants is presented. The method utilizes a maximum instead of a slope in the rate constant calculation; rate constant error estimates are easily obtainable. RlCHARD 0 . VIALE, Department of Biochemistry, School of Medicine, University of Pennsylvania, Philadelphia, Pa. 19104 Anal. Chem., 42, 1 8 4 3 ( 1 9 7 0 )
Rapid Acid-Hydrogen Peroxide Decomposition and Solubilization of Copper Phthalocyanines for Analysis DANIEL KRUH, lmperial Color and Chemical Department, Hercules Incorporated, Glens Falls, N . Y. 12801 Anal. Chem., 42, 1849 ( 1 9 7 0 )
ANALYTICAL CHEMISTRY, VOL. 42, NO. 14, DECEMBER 1970
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