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1.
Neotrop Entomol ; 49(5): 696-703, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32468341

RESUMO

The present paper describes a new species of Actinote (Nymphalidae, Heliconiinae, Acraeini), Actinote keithbrowni Freitas, Francini & Mielke sp. nov., from southeastern Brazil, based on morphological and molecular data. The new species is very similar in wing pattern to Actinote eberti, within what we term the "light-gray mimicry complex." The host plants and immature stages of the new species are unknown. Actinote keithbrowni sp. nov. is one of the rarest species of Actinote from Brazil: in total, only eight individuals of this species are known from a narrow region of the Itatiaia massif despite years of collecting effort in that region since the 1940s.


Assuntos
Borboletas/anatomia & histologia , Borboletas/classificação , Animais , Brasil , Cor , Ecossistema , Feminino , Genitália/anatomia & histologia , Masculino , Filogenia , Asas de Animais/anatomia & histologia
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 57(10): 2001-8, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11666080

RESUMO

The absorption and emission spectroscopies of Er3+ doped and Er3+/Yb3+ codoped Ca(PO3)2, Sr(PO3)2 and Ba(PO3)2 glasses have been studied. From the Judd-Ofelt intensity parameters, the spontaneous emission probabilities of some relevant transitions and the radiative lifetimes of several excited states of Er3+ have been calculated. The decay curves of the Er3+ emission at 1.5 microm have been measured at different temperatures. The data have been fitted using a stretched exponential function and the obtained experimental lifetimes have been compared with the calculated radiative lifetimes. The difference between the experimental and calculated lifetimes is attributed to the presence of traces of OH groups in the host glasses. The absolute OH content in some glasses has been determined from the infrared spectra. The emission spectra at 1.5 microm of the Er3+ ion in the codoped glasses have been measured at different temperatures. The integrated emission intensities decrease significantly on passing from room temperature to 13 K, suggesting a temperature dependence of the rate of the energy transfer process between Yb3+ and Er3+.


Assuntos
Érbio/química , Vidro/química , Íons , Espectrofotometria/métodos , Itérbio/química , Fenômenos Biofísicos , Biofísica , Temperatura , Fatores de Tempo
5.
Phys Rev B Condens Matter ; 38(2): 1468-1472, 1988 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-9946410
6.
Phys Rev B Condens Matter ; 34(4): 2936-2938, 1986 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9940005
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