No abstract

In this research, the mathematical model associated with the hydrothermal dehydration process of Nixtamalized Corn Grains (NCG) with different Steeping Time (ST) values, allows the fitting of experimental data with initial moisture M0 and the equilibrium moisture ME as a function of Isothermal Dehydration Time (IDT). The moisture percentage for any time t and dehydration rate (isolines M(t) and isolines vI respectively) of the NCG is shown by means of matrix graphics as a simultaneous function of IDT and ST. The relationship between initial dehydration rate v0 and initial moisture M0 establishes as a function of ST. Also, the mathematical model associated with the solution of the second Fick’s law allows calculating the diffusivity rate vk (H2O molecules out of NCG) and verify that the rate of change in moisture and the dynamical proportionality constant k has a non-linear dependence on the IDT and that k is directly proportional to Deff. The k values strongly relate to ST and the calcium ions percentage into NCG according to solubility lime values into cooking water (or nejayote) as a function of decreasing temperature when ST increases.

Este es un artículo de acceso abierto bajo la licencia Creative Commons 4.0 Atribución-No Comercial (CC BY-NC 4.0 Internacional).

"Thin films deposition kinetics of BaXSr1-XTiO3 (BST)/nichrome is modeled by the stoichiometric rate of a perovskite-type material such as ABO3, where cations A, B, and the anion oxygen should ideally have a 1:1:3 rate, respectively. The experimental stoichiometry data measured by EDS on films of 240 nm, and the Ba/Sr, (Ba+Sr)/Ti rates considered in percentages starting from arithmetic and the sigmoidal relationship between Ba and Sr. They show relationships in sigmoidal, exponential, and parabolic mathematical functions that together describe the BST thin films deposition kinetics by means of RFMagnetron Co-Sputtering (RFMCS). The proposed mathematical model is fundamental to optimize, explain and use the deposition process working conditions, such as the working pressure, the Ar/O2 rate in percentage, and sccm. The controlled applied power on each BaTiO3 (BTO) and SrTiO3 (STO) targets achieve more accurate stoichiometry in thin films deposition for solid solutions on quaternary materials."