Dehydroascorbic acid, p-benzoquinone, anthraquinone disulfonie acid, and chloranil gave strong responses. The fact that vitamin K3 catalyzes the reaction makes it probable that vitamins Ki and K3, which also contain a naphthaquinone nucleus, would function in this manner.Sodium dehydrotartrate showed no catalytic effect despite the fact that it is a 1,2-diketone.The sensitive detectability of 1,2-diketones and quiñones, through their catalytic activity in the formaldehyde-1,2dinitrobenzene system, makes possible new tests for anthracene, phenanthrene, and inositol, because these compounds are easily converted into corresponding catalytically active compounds.
DETECTION OF ANTHRACENE AND PHENANTHRENEAnthracene and phenanthrene are converted into anthraquinone and phenanthraquinone, respectively, by evaporation with concentrated nitric acid. These products react satisfactorily wdth the reagent mixture, if the reagent is precipitated in a surface-rich form from its benzene solution by evaporation of the solvent.
Mn and Zn are determinable in Al ores, intermediates, and finished metal by atomic-absorption spectrophotometry, using a particular burner, if suitable separation procedures are employed. Zn may be separated by chloro—anion exchange. Mn is conveniently extracted into chloroform by complexing with 8–hydroxyquinaldine at pH 12. Results from analyses of known samples show that the method is suitable for the calibration of emission spectrographs.
This is the seventeenth review on nonferrous metallurgical analysis and covers the two-year period from September 1976 through August 1978 as documented by Chemical Abstracts, Analytical Abstracts, World Aluminum Abstracts, and Government Reports Announcements. The following journals also were surveyed for the same period: Analytical Chemistry, Applied Spectroscopy, Analytica Chimica Acta, The Analyst, and Talanta. Wherever possible, the abstract number of the abstracting service has been included in the bibliographic citation.As in the past (223), this review is limited to those analytical methods of interest in the nonferrous metals industry. Many interesting methods potentially applicable to this field are not included because of space considerations. However, some general methods are included because they appear to the authors to be particularly useful or novel.One book related to the analysis of light metals was published in Russia by Tikhonov (2,56) entitled: "Determination of Aluminum in Metals and Alloys." A revised edition of a commonly used reference book by Sandell: "Colorimatric Determination of Traces of Metals" was also issued (4th ed., Wiley, New York, 1978).
PROCEDURES FOR MULTIPLE CONSTITUENTSA compilation of procedures for the determination of multiple constituents in light metal materials is given in Table I. Some of these procedures will be highlighted in the following sections which are arranged according to those instrumental techniques most commonly used in the light metals industry.
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