Representations of an algebra of the Gell-Mann-Dashen type

LetG denote the infinitedimensional Lie algebra given by communtation relations [a _m ,a _n ] =c a _m+n (m, n=0, 1, ...), wherec are structure constants of the arbitrary centerless Lie algebra. The paper is devoted to the construction of a certain class of skewsymmetric irreducible representations (so called F-representations) of the algebraG .     

The syn and anti Steric Course in Bimolecular Olefin-Forming Eliminations

Earlier evidence led to the view that in bimolecular olefin-forming eliminations the anti steric course is generally preferred over the syn. Recent experiments, however, show that in some common bimolecular elimination reactions, notably those involving onium bases, syn- and anti-eliminations proceed side by side, the former preferentially leading to the trans- and the latter to the cis-olefins.     

Arc plasma in air with calcium and fluorine—I. Calculation of the plasma composition

The equilibrium composition of the gaseous system containing N, O, C, F and Ca was calculated in the temperature range between 298 and 7000 K. This gas mixture corresponds to the plasma of a d.c. low current arc freely burning in the air between graphite electrodes in the presence of fluorine and calcium.     

Polarometrische Bestimmung von Methylenblau mit Phosphorwolframsäure

Zusammenfassung Ein Mol Phosphorwolframsäure reagiert in 2,5M Salzsäure mit 5 Mol Methylenblau unter Bildung eines Niederschlages, der in Wasser und verdünnten Mineralsäuren unlöslich ist. Diese Reaktion wurde zur polarometrischen Bestimmung von Methylenblau benützt. Bei Einhaltung aller Versuchsbedingungen, besonders der Acidität der Lösung, sind die Resultate gut. Der Äquivalenzpunkt der Titration wurde unter Verwendung einer modifizierten Rechenmethode bestimmt.

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Polarometric determination of methylene blue with phosphotungstic acid

Summary One mol phosphotungstic acid reacts in 2.5M hydrochloric acid with 5 mol Methylene Blue creating a precipitate insoluble in water and in diluted mineral acids. The given reaction was applied for the polarometric determination of Methylene Blue. Under keeping of all experimental conditions, especially of the solution acidity, the results are good. The equivalence point of the titration was determined using a modified method of calculation.

     

Basicity of nitropyrazoles and their simultaneous spectrophotometric determination

The protonation constants of some 1-, 3(5)-, 3-, 4- and 5-nitropyrazoles have been determined, and compared with those of nitroimidazoles. The effect of the position of the nitro group in the pyrazole and imidazole ring is discussed. The ortho effects of the nitro group in pyrazole and imidazole are compared and found to have identical values. The effect of the nitro group on protonation constants is greater when the nitro group is close to the pyridine nitrogen atom. This, together with the ability of N-unsubstituted nitropyrazoles to dissociate to give nitropyrazole anions, with an accompanying shift of the spectra to longer wavelengths, permits the simultaneous spectrophotometric determination of nitropyrazoles.     

Glass forming ability and the electrical properties of semiconducting AsxTe1−x glasses

In the binary system of As-Te semiconducting glasses the glass forming ability is evaluated using the DTA data and the conditions of glass formation are discussed. A comparison of the thermophysical parameters with the electrical activation energy is made and the linear dependence between the atomization enthalpy and the activation energy is discussed.     

External inversion,internal inversion,and reflection invariance

Having in mind that physical systems have different levels of structure we develop the concept of external, internal and total improper Lorentz transformation (space inversion and time reversal). A particle obtained from the ordinary one by the application of internal space inversion or time reversal is generally a different particle. From this point of view the intrinsic parity of a nuclear particle (elementary particle) is in fact the external intrinsic parity, if we take into account the internal structure of a particle. We show that non-conservation of the external parity does not necessarily imply noninvariance of nature under space inversion. The conventional theory of beta-decay can be corrected by including the internal degrees of freedom to become invariant under total space inversion, though not under the external one.     

Kinetics of the fluorescence of poly(N-vinylcarbazole) and poly(N-vinylcarbazole) with 2,4,7-trinitrofluorenone in the solid state

The fluorescence decay time measurements by the stroboscopic method have been made on films of amorphous poly(N-vinylcarbazole) (PVCA) and PVCA doped with 2,4,7-trinitrofluorenone (TNF). The obtained lifetimes of two excimer species have at 77 K and at 300 K values of about 43 ns and 9 ns, which are similar to other measurements. The kinetics of excimer fluorescence and energy transfer in PVCA films are described by a simple model of the Stern-Volmer type. It assumes the fast migration of localized singlet excitons and their trapping in two species of excimer traps.We propose a modified kinetic model for films of PVCA with TNF. In this model we assume besides the exciton migration and trapping on excimer and impurity traps also the direct energy transfer from two excimer species to charge transfer complexes of PVCA with TNF by the Förster dipole-dipole mechanism. The estimated critical distance of this transfer are about 10 Å.