Skip navigation
Universidade Federal da Bahia |
Repositório Institucional da UFBA
Use este identificador para citar ou linkar para este item: https://repositorio.ufba.br/handle/ri/5511
Registro completo de metadados
Campo DCValorIdioma
dc.contributor.authorCavasso Filho, Reinaldo Luiz-
dc.contributor.authorOliveira, Sergio Pilling Guapyassu de-
dc.contributor.authorAndrade, Diana Paula de Pinho-
dc.contributor.authorNascimento, E. M.-
dc.contributor.authorMarinho, Ricardo dos Reis Teixeira-
dc.contributor.authorBoechat-Roberty, Heloisa Maria-
dc.contributor.authorCoutinho, Lúcia Helena-
dc.contributor.authorSouza, Gerardo Gerson Bezerra de-
dc.contributor.authorCastilho, Roberto Barbosa de-
dc.contributor.authorLago, Alexsandre Figueiredo-
dc.contributor.authorBrito, Arnaldo Naves de-
dc.creatorCavasso Filho, Reinaldo Luiz-
dc.creatorOliveira, Sergio Pilling Guapyassu de-
dc.creatorAndrade, Diana Paula de Pinho-
dc.creatorNascimento, E. M.-
dc.creatorMarinho, Ricardo dos Reis Teixeira-
dc.creatorBoechat-Roberty, Heloisa Maria-
dc.creatorCoutinho, Lúcia Helena-
dc.creatorSouza, Gerardo Gerson Bezerra de-
dc.creatorCastilho, Roberto Barbosa de-
dc.creatorLago, Alexsandre Figueiredo-
dc.creatorBrito, Arnaldo Naves de-
dc.date.accessioned2012-03-05T18:50:02Z-
dc.date.issued2011-
dc.identifier.issn1365-2966-
dc.identifier.urihttp://www.repositorio.ufba.br/ri/handle/ri/5511-
dc.descriptiontexto completo: acesso restrito. p.2214–2222.pt_BR
dc.description.abstractAn experimental photochemistry study involving gas- and solid-phase amino acids (glycine, DL-valine, DL-proline) and nucleobases (adenine and uracil) under soft X-rayswas performed. The aim was to test the molecular stabilities of essential biomolecules against ionizing photon fields inside dense molecular clouds and protostellar discs analogs. In these environments, the main energy sources are the cosmic rays and soft X-rays. The measurements were taken at the Brazilian Synchrotron Light Laboratory (LNLS), employing 150-eV photons. In situ sample analysis was performed by time-of-flight mass spectrometer (TOF-MS) and Fourier transform infrared (FTIR) spectrometer, for gas- and solid-phase analysis, respectively. The half-life of solid-phase amino acids, assumed to be present at grain mantles, is at least 3 × 105 and 3 × 108 yr inside dense molecular clouds and protoplanetary discs, respectively. We estimate that for gas-phase compounds these values increase 1 order of magnitude since the dissociation cross-section of glycine is lower in gas phase than in solid phase for the same photon energy. The half-life of solid-phase nucleobases is about 2–3 orders of magnitude longer than found for amino acids. The results indicate that nucleobases are much more resistant to ionizing radiation than amino acids. We consider these implications for the survival and transfer of biomolecules in space environments.pt_BR
dc.language.isoenpt_BR
dc.sourcedoi:10.1111/j.1365-2966.2010.17840.xpt_BR
dc.subjectastrobiologypt_BR
dc.subjectastrochemistrypt_BR
dc.subjectmolecular datapt_BR
dc.subjectmethods: laboratorypt_BR
dc.subjectISM: moleculespt_BR
dc.subjectX-rays: ISMpt_BR
dc.titlePhotostability of gas- and solid-phase biomolecules within dense molecular clouds due to soft X-rayspt_BR
dc.title.alternativeMonthly Notices of the Royal Astronomical Societypt_BR
dc.typeArtigo de Periódicopt_BR
dc.identifier.numberv. 411.pt_BR
dc.embargo.liftdate10000-01-01-
Aparece nas coleções:Artigo Publicado em Periódico (ICADS)

Arquivos associados a este item:
Arquivo Descrição TamanhoFormato 
j.1365-2966.2010.17840.x.pdf
  Restricted Access
10,22 MBAdobe PDFVisualizar/Abrir Solicitar uma cópia
Mostrar registro simples do item Visualizar estatísticas


Os itens no repositório estão protegidos por copyright, com todos os direitos reservados, salvo quando é indicado o contrário.