Published 1984 | Version v1
Miscellaneous Open

Study of the radiolysis of tetracycline hydrochloride in powder form, in aqueous solutions and in benzyl alcohol, at 77K, by electron paramagnetic resonance spectroscopy

Creators

Description

The radiolysis of tetracycline hydrochloride in powder form, dissolved in benzyl alcohol and in acid, neutral and alkaline aerated aqueous solutions at 77K is studied by electron paramagnetic resonance spectroscopy. Mechanisms of reactions that occur in the radiolysis of these systems are proposed and some aspects of the reactions that occurs with electrons and with hydrogen atoms at 77K are investigated, since tetracycline hydrochloride captures both paramagnetic species. Also discussed is the influence of some factors in the migration of these species at 77K, such as: the position of solutes, the crystalline structure of the solvent, the kinetic energy of the species and the angle of incidence in the channeling. The rate constants for the reaction between the electron and physical and chemical traps which are present in the alkaline aerated aqueous solutions, at 77k, are calculated. The values found are, respectively: k=9.6 x 1015 1 mol-1 s-1 and k= 1.8 x 1010 1 mol -1 s-1. (Author)

Availability note (English)

MF available from INIS under the Report Number.

Abstract (Portuguese)

Estuda-se a radiolise do cloridrato de tetraciclina em po, dissolvido em alcool benzilico e em solucoes aquosas aeradas acidas, neutras e alcalinas, a 77K, por espectroscopia de ressonancia paramagnetica eletronica. Propoe-se mecanismos de reacoes de ocorrem na radiolise e investiga-se alguns aspectos das reacoes que ocorrem com os eletrons e com os atomos de hidrogenio a 77K, uma vez que o cloridrato e capaz de capturar essas duas especies paramagneticas. Discute-se tambem a influencia de fatores como a posicao dos solutos, a estrutura cristalina do solvente, a energia cinetica das especies, o angulo de incidencia na canalizacao. Calcula-se as constantes de velocidade para a reacao do eletron com as armadilhas fisicas e quimicas presentes em solucoes aquosas aeradas alcalinas, a 77K, as quais sao, respectivamente: K=9,6 x 1015 1 mol -1 s-1 e K=1,8 x 10101 mol-1s-1. (Autor)

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Additional details

Additional titles

Original title (Portuguese)
Estudo da radiolise do cloridrato de tetraciclina em po, em solucoes aquosas e em alcool benzilico, a 77K, por espectroscopia de ressonancia paramagnetica eletronica

Publishing Information

Imprint Pagination
183 p.
Report number
INIS-BR--266

INIS

Country of Publication
Brazil
Country of Input or Organization
Brazil
INIS RN
16033660
Subject category
S38: RADIATION CHEMISTRY, RADIOCHEMISTRY AND NUCLEAR CHEMISTRY;
Resource subtype / Literary indicator
Thesis
Descriptors DEI
AERATION; AQUEOUS SOLUTIONS; BENZYL ALCOHOL; BINDING ENERGY; CHLORTETRACYCLINE; DIAGRAMS; ELECTRON SPIN RESONANCE; IONIZATION POTENTIAL; PH VALUE; RADIOLYSIS; REACTION KINETICS; SAMPLE PREPARATION; TEMPERATURE CONTROL; TRAPS
Descriptors DEC
ALCOHOLS; ANTIBIOTICS; AROMATICS; CHEMICAL RADIATION EFFECTS; CHEMICAL REACTIONS; CONTROL; DECOMPOSITION; DISPERSIONS; DRUGS; ENERGY; HOMOGENEOUS MIXTURES; HYDROXY COMPOUNDS; INFORMATION; KINETICS; MAGNETIC RESONANCE; MIXTURES; ORGANIC COMPOUNDS; RADIATION EFFECTS; RESONANCE; SOLUTIONS; TETRACYCLINES