Quantization of gauge fields through fibre bundle multiconnectivity

A geometric model for the quantum nature of interaction fields is proposed. We utilize a trivial fibre bundle whose typical fibre has a multiconnectivity characterized by a discrete group Γ. By seeing Γ as a gauge group with global action on each fibre, we show that the corresponding field strength is non-zero only on the future part of the light cone whose vertex is at the interaction point. When the interaction is submitted to the symmetries of a Lie group G, we consider the gauge group G x Γ. The field strength of the gauge having this group includes a term expressing the quantization of the interaction field described by G. This geometric interpretation of quantization makes use of topological arguments similar to those applied to explain the Aharonov-Bohm effect. Two examples show how this interpretation applies to the cases of electromagnetic and gravitational fields.      

Selective flotation-separation and spectrophotometric determination of cadmium using phenanthraquinone monophenythiosemicarbazone.

A simple, selective and sensitive procedure is described for the preconcentration by flotation followed by spectrophotometric determination of trace amounts of Cd(II). Cadmium forms an intense red 1:2 complex with phenanthraquinone monophenylthiosemicarbazone (PPT) at pH > or = 6. The colored Cd-PPT complex was floated quantitatively with oleic acid (HOL) surfactant at pH 6.5, exhibiting maximum absorbance at 520 nm and having a molar absorptivity of 2.4 x 10(5) L mol(-1) cm(-1). The stability constant of the formed complex is 1.5 x 10(12); log K = 12.2. Beer's law was obeyed over the concentration range 0.01-0.34 mg/L. The Sandell sensitivity and relative standard deviation are 0.4 ng/cm2 and 2.6%, respectively. The results obtained spectrophotometrically were compared to those obtained by AAS analysis. The analytical parameters affecting flotation and hence determination have been thoroughly investigated. The proposed procedure was successfully applied to the determination of Cd(II) traces in certified and real human hair samples as well as in natural waters. The structure of the complex formed and the mechanism of flotation were proposed.     

Solochrome Black P. V. as a new reagent in chelatometry

Summary Solochrome Black P. V. with its distinct acid-base properties has proved to be a suitable reagent for the spectrophotometric microdetermination of magnesium either alone or in the presence of zinc, calcium, cobalt, or copper. Interference due to many cations is simply eliminated. Spectrophotometric titration of magnesium with EDTA is investigated. Sensitivity of the method allows determining of 0.05 to 3 ppm Mg with reasonable accuracy.

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Zusammenfassung Solochromschwarz P. V., das als Säure-Base-Indicator verwendet werden kann, ist auch ein geeignetes Reagens zur spektrophotometrischen Mikrobestimmung von Magnesium. Zink, Calcium, Kobalt, Kupfer und andere Kationen können in einfacher Weise maskiert werden. Die spektrophotometrische Titration des Magnesiums mit ÄDTA-Lösung wird ebenfalls untersucht. 0,05–3 ppm Mg können mit guter Genauigkeit bestimmt werden.

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Part II:Khalifa, H., and M. M.Khater: Z. analyt. Chem.183, 241 (1961).     

A rapid potentiometric method for analysis of some minerals and basic refractories

Rapid and quite reliable procedures for analysis of phosphate, quartzite and fluorspar-minerals; chromite, chromemagnesite and magnesite chrome bricks-basic refractories are described. They are based on titrating unconsumed EDTA with Hg(II)-nitrate using silver amalgam as the indicator electrode, with breaks of reasonable order of magnitude lying within the immediate vicinity of the expected end points.     

Extraction of certain elements from aqueous methanol, ethanol and acetone by tridodecylamine and tributyl phosphate

The extraction of silver, mercury, selenium, zinc, cobalt and iron with tridodecylamine (TDA) and tributyl phosphate (TBP) from hydrochloric acid solutions in aqueous methanol, ethanol and acetone is reported. The presence of these additives increases extraction for some elements and decreases it for others. The effect is generally greater with TDA than with TBP.     

Back titration with mercuric nitrate in alkaline medium

Summary Potentiometric back titration of excess EDTA than required to chelate with gallium or indium using mercuric nitrate as the back titrant provides an excellent method for the determination of amounts of both metal ions in the order of 0.07 to 11 and 0.05 to 18 mg, respectively. The method is further successfully applied for analysis of binary and ternary mixtures of gallium or indium with some other cations using simple procedures.

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Zusammenfassung Gallium oder Indium können in Mengen von 0,07–11 bzw. 0,05 bis 18 mg bestimmt werden, wenn man mit einem überschuß an äDTA versetzt und mit Quecksilber(II)-nitratlösung potentiometrisch zurücktitriert. Auf einfache Weise können auch binäre und ternäre Mischungen von Ga oder In mit einigen anderen Kationen erfolgreich analysiert werden.

     

BackTitration with mercuric nitrate in alkaline medium

Summary Potentiometric back titration of excess EDTA than required to chelate with lanthanum using mercuric nitrate as the back titrant provides an excellent method for the estimation of this metal. By aid of the method amounts of lanthanum in the order of 50 g up to 60 mg were determined with high accuracy in most cases. The method is further successfully applied for analysis of pairs of La with Th, Ba, Hg^II, Mn^II, Cu, Zn, Cd, Ni, Co or Bi using a suitable precipitant or masking agent or selective P_H. NH₄F has proved to be a suitable masking agent for small amounts of lanthanum.See also Z. analyt. Chem. 169, 109 (1959).