Propriedades vibracionais de semicondutores amorfos

Orientador: Cylon Eudóxio Tricot Gonçalves da SilvaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb WataghinResumo: Apresentamos um modelo para a dinâmica de rede do a-Si1-xNx. Esse modelo se baseia em um Hamiltoniano de Born, resolvido na aproximação da rede de Bethe. A partir da densidade local de modos normais de vibração, obtida pelo método das funções de Green, analisamos o espectro de absorção no infravermelho desse materialAbstract: We introduce a model for the lattice dynamics of a-Si1-xNx. This model is based on a Born Hamiltonian, solved in the Bethe lattice approximation. Starting from the local density of vibrational states, we analyze the infrared absorption spectra of this materialMestradoFísicaMestre em Físic

Cold storage of ‘Palmer’ mangoes sorted based on dry matter content using portable near infrared (VIS-NIR) spectrometer

The objective of this study was to use dry matter (DM) calibration models to sort ‘Palmer’ mangoes prior cold storage and to evaluate the physiological and chemical changes during the storage period. PLS model developed with fruit from 2015/2016 season was not adequate to predict DM content in fruit from 2016/2017 (not adjusted R2). Therefore, VIS‐NIR spectra from 2016/2017 season were incorporated into data set and a new model was developed (RMSEcv of 10.5 g.kg−1, urn:x-wiley:01458892:media:jfpp13644:jfpp13644-math-0001 of 0.75). With the new model, ‘Palmer’ mangoes were sorted into two maturity stages (150 g.kg−1 and 110 g.kg−1) which resulted in quality differences mainly in relation to DM and SSC. Portable VIS‐NIR spectrometer can be used to sort fruit according to maturity stages based on DM content and this classification affect fruit quality during cold storage as fruit with higher DM (150 g.kg−1) presented better quality than fruit with lower DM (110 g.kg−1)