Showing papers in "Analytica Chimica Acta in 1954"

TL;DR: The removal of sodium citrate and phosphate buffers from amino acids in the effluent from ion exchange chromatograms can be accomplished by one-step desalting on basic or acidic resins, resulting in salt-free solutions suitable for examination by paper chromatography or for the isolation of amino acids for further characterization.

TL;DR: The conditions for the estimation of peroxides by three established, methods have been re-examined in detail in detail as mentioned in this paper, where Amyl alcohol is recommended as a decolourizer for the reagent since the red colour produced by the action of the peroxideides is stabilized, permitting accurate spectrophotometric measurements.

TL;DR: In this paper, the steric hindrance of the 2-methyl group has been investigated in terms of steric strength of the metal-chelate bonds in 2- and 4-methyl-8-hydroxyquinoline.

TL;DR: An apparatus for the wet ashing of organic material is described in this article, which makes possible the extraction of large quantities of organic matter with pure, ash-free reagents and the determination of various constituents in the samples.

TL;DR: In this paper, a photometrical method for the determination of trace and higher amounts of aluminium in steels, non-ferrous alloys and in glass was proposed, which enables a practically specific photometric determination of aluminium.

TL;DR: The mechanism of the classical color reaction between chromate and carbazide has been studied in solution from various physico-chcmical points of view as discussed by the authors, which leads to the conclusion that tlie chromate-carbazidc reaction is a composite one involving preliminary oxidation followed subsequently by complex formation.

TL;DR: In this article, it was derived theoretically that a sharp end-point of this spectrophotometrical titration is defined, in order of importance, by: 1. * K C ⪢ * K I (numerically speaking, log *K C *K I should be at least 4); 2.

TL;DR: In this article, a radioactivation method for the determination of oxygen in beryllium metal powder is described, where the sample, mixed with, lithium fluoride, is irradiated in the Harwell Pile, fluorine-18 chemically separated and its activity compared with that from standards similarly treated.

TL;DR: In this article, a method is presented by means of which each constituent of a mixture of ortho-, pyro-, tri-, trimeta-, and tetrametaphosphate can be separated and determined.

TL;DR: In this article, the general principles of photoelectric complex formation titrations using metal indicators are given and mathematical equations necessary for the exact determination of the equivalence point are derived for titrations with one-colour and two-colour indicators.

TL;DR: In this paper, the reaction of aluminium with oxine was studied by a new heterometric method and the composition of the intermediate compounds which are formed at room temperature were given, with an error between zero and 0.5 microgram per ml.

TL;DR: In this article, an improved method for the lodometric dctermination is described and its precision and accuracy are discussed; it is concluded that sensitivity is high, as is the precision when suitable oxidation conditions are chosen, but that the accuracy is not so high.

TL;DR: In this paper, it has been shown that all the platinum metals with the exception of osmium can be estimated as sulphide if the solution containing the metal is treated with a large excess of alkali sulphide followed by excess of acetic acid and ammonium acetate.

TL;DR: In this paper, a method for direct determination on filter paper of nickel, after chromatographic separation of interfering elements, was developed, where the sample is dissolved in 3 N hydrochloric acid and the solution is spotted on filter papers, together with standard solutions of nickel.

TL;DR: In this paper, the titrated zinc solution may contain an excess of Cd (85%), and the analysis with Ni or Co is very limited, with an error of ⩽ 1%.

TL;DR: In this paper, the titration procedure described in previous papers has been applied to a study of some metallic chelates of dimethylglyoxime and of its O-monomethyl ether.

TL;DR: In this article, it was shown that formic acid can be quantitatively oxidized by ceric sulphate in the presence of concentrated sulphuric acid, and the excess ceric sulfate is determined by titrating against ferrous ammonium sulphate.

TL;DR: In this paper, a method for the separation of La-Ac mixtures and certain rare earth mixtures by continuous electrophoresis on paper sheets using 1% citric acid cis electrolyte and a potential of 300 V.

TL;DR: In this article, a heteromctric method was presented for the direct determination of magnesium with oxine in the presence of excesses of aluminium, zinc, cadmium, manganese or calcium.

TL;DR: In this paper, a stationary mercury-plated platinum electrode in a rapidly stirred solution has been applied to the polarographic and coulometric determination of trace amounts of lead(II).

TL;DR: In this article, a series of determinations in a narrow range is to be carried out by direct weighing of zirconium mandelate, more accurate results might be obtained by determination of the appropriate factor for that range.

TL;DR: In this paper, a titration procedure for Al based on the reaction of Al and complexone III (disodium salt of ethylenediaminetetra-acetic acid, (versene) at pH 3.5-4.3 is described.

TL;DR: In this article, a method was developed whereby molybdenum is extracted from digests of plant materials by means of a-benzomoxime and chloroform from a medium of 1 % sulphuric acid solution.

TL;DR: In this article, the behavior of reagents containing reactive groupings analogous to those of 8-hydroxyquinoline, but arranged as to form six-membered ring chelates with metal ions, was studied.

TL;DR: In this article, the stability of chelates of 2-( o -hydroxyphenyl)-pyridine, pyridine and quinoline were determined by the Calvin-Bjerrum potentiometric titration technique.

TL;DR: In this article, the photometric molybdovanadophosphoric acid method was used to determine the phosphorus in silicate rocks, following decomposition of the sample with nitric-hydrofluoric acid.

TL;DR: A semimicro-method based on partition chromatography is described for the determination of the saturated, straight-chain fatty acids C 10 -C 24, using a silicagel column, which is highly suitable for this Chromatographie analyses.

TL;DR: In this paper, a method for the determination of uranium (VI) by a heterometric titration with K4[Fe(CN)6 was presented, and the error amounts to 0.3%.

TL;DR: In this article, a new heterornetric method was presented for a quick micro-determination of copper with oxine, with an accuracy of a few tenths of a microgram per nil.

TL;DR: In this paper, a new heterometric method is presented for a rapid micro-determination of copper with oxine, with an accuracy of 0-I-0 microgram per ml.