Aparato experimental para medidas de atividade óptica da sacarose usando um amplificador Lock-in

Leduc Hermeto de Almeida Fauth, Pablo Diniz Batista

Resumo


Este trabalho apresenta a montagem de um polarímetro digital para medidas de atividade óptica em modo pulsado. Em termos de instrumentação científica, foi desenvolvido um circuito eletrônico para medir a intensidade luminosa usando um fotodetector em conjunto com outros componentes ópticos e um amplificador Lock-in. Além disso, um porta amostra foi projetado utilizando uma lente de quartzo acoplada em uma tampa e conectada a um tubo de PVC. O desempenho do sistema de medidas é investigado considerando a resolução e o limite de detecção a partir da determinação da rotação óoptica específica da sacarose. Este trabalho foi desenvolvido tendo como base o paradigma open source hardware e, portanto, toda a documentação estará disponível para que possa ser utilizada e aprimorada pela comunidade científica.

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DOI: http://dx.doi.org/10.7437/nt-cbpf.v8i2.313