950 resultados para DIDATTICA DELLA LINGUA ITALIANA,15317,Scienze della Formazione,0013,Scienze della formazione primaria,1313,ESAME INTEGRATO DI LINGUISTICA ITALIANA - DIDATTICA DELLA LINGUA ITALIANA (II MODULO),22123,SCUOLA ELEMENTARE,253,MAIOR DELLA MATEMATICA E DELLE SCIENZE SPERIMENTALI,231,2007,3
Resumo:
The synthesis and photophysical characterization of a PPV-type copolymer containing a fluorene derivative alternated with thiophene units is presented: poly(9,9'-dioctylfluorene-thiophene) (LAPPS29). Photophysical studies demonstrated that in the solid state only preformed ground state aggregates are responsible for exciton formation. These aggregates are formed with a wide range of size distribution. The emission from isolated segments is quenched either by resonant energy transfer, or by migration processes. Also, the main photovoltaic parameters are discussed in connection with the photophysical behavior.