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Considerações Temodinâmicas das Isotermas

DOI: http://dx.doi.org/10.15871/1517-8595/rbpa.v10n1p83-94

http://rbpaonline.com/ 

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Kil J. B. Park1, Kil J. Park2, Félix E. P. Cornejo3 & Inácio M. D. Fabbro4

 

Abstract: Apresentam-se as considerações termodinâmicas das isotermas e as equações empíricas mais usuais na literatura. Uma das importantes aplicações das equações de isotermas é a energia de relacionamento da água com a matriz sólida que é traduzida na energia de adsorção. A outra importante consideração é acerca dos valores de monocamada molecular de água, que indicam a relação com as reações químicas que determinam a deterioração dos materiais biológicos, através das áreas expostas da matriz sólida.

Key words: atividade de água, modelos teóricos, modelos empíricos, energia de sorção, superfície exposta.

 

Resumo: The thermodynamic considerations of the isotherms and the more usual empirical equations in literature are presented. One of the important applications of the isotherm equations is the energy of water relationship with matrix solid that is translated in the adsorption energy. The other important consideration is concerning the values of water molecular monolayer, which indicate the relation with the chemical reactions that determine the deterioration of the biological materials, through the displayed areas of the solid matrix.

Palavras-chave: water activity, theoretical models, empirical models, sorption energy, exposed surface.

 

1 Doutorando em Engenharia Agrícola da Faculdade de Engenharia Agrícola da Universidade Estadual de Campinas. Caixa Postal 6011. CEP: 13083-875. Campinas-SP, Brasil. E-mail: kil.park@agr.unicamp.br.
2 Professor Titular - Faculdade de Engenharia Agrícola – Universidade Estadual de Campinas. Caixa Postal 6011. CEP: 13084-971. Campinas-SP, Brasil. E-mail: kil@agr.unicamp.br.
3 Pesquisador da Embrapa Agroindústria de Alimentos. Felix@ctaa.embrapa.br.
4 Professor Titular - Faculdade de Engenharia Agrícola – Universidade Estadual de Campinas. Caixa Postal 6011. CEP: 13084-971. Campinas-SP, Brasil. E-mail: inacio@agr.unicamp.br.

  

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