Banca de DEFESA: LAURA BEZERRA PORTUGAL AROUCA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : LAURA BEZERRA PORTUGAL AROUCA
DATA : 22/05/2020
HORA: 14:30
LOCAL: ConferênciaWeb
TÍTULO:

PROLINE RADIOLYSIS INDUCED BY ELECTRONS ANALYZED BY INFRARED SPECTROSCOPY

PALAVRAS-CHAVES:

Proline – Radiolysis – Electron – Infrared Spectroscopy – Annealing – Amino acids

PÁGINAS: 60
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Física
RESUMO:

Studies have identified the photolysis and radiolysis of icy mantles of interstellar dust
grains as a possible source of amino acids, suggesting, along with the discovery of complex
organic compounds in meteorites and comets, that prebiotic molecules may have been brought
to the primitive Earth by the impact of these celestial bodies. Amino acids and their precursors
have been studied with the purpose of understanding physicochemical processes induced by
ionizing radiation, like electrons, photons and cosmic rays, in astrophysical environment. This
present study aims to study the interaction between the L-Proline (C5H9NO2), sublimated on an
ZnSe substrate, and 2 keV electrons beam in an experimental chamber under high vacuum at
room temperature. And more specifically, our goal is to analyse, by infrared spectroscopy, the
radiolysis and obtain cross section values. One of the films was previously heated at 120°C to
analyse the influence of annealing during the sample degradation.
The results obtained showed that electron-induced proline radiolysis can be
characterized using the astrophysical ice analogues model irradiated by swift ion beam.
Rearrangement and destruction cross section values were determined and compared for the two
films prepared with and without annealing, concluding that the sample heating did not promote
significant changes in the sample rearrangement process although it has modified the rate of
destruction by the impact of electrons.

MEMBROS DA BANCA:
Interno - 1194645 - FREDERICO VASCONCELOS PRUDENTE
Externo à Instituição - MANOEL GUSTAVO PETRUCELLI HOMEM - UFSCAR
Presidente - 2422135 - RICARDO DOS REIS TEIXEIRA MARINHO