The temperature influence on the oxidation stability of biodiesel from ternary mixture of vegetable oil and animal fat (50% of soybean oil, 20% of beef tallow, and 30% of poultry fat) was evaluated at temperatures ranging from 110 to 130 °C applying the Arrhenius and Eyring equations. The kinetics and thermodynamics parameters determined, considering first-order reaction rate kinetics, were rate constant (k), varying from 0.5479 to 1.7110 h −1 , activation energy (E a ) of 72.01 kJ mol −1 , preexponential factor (A) of 3.84 × 10 9 h −1 , enthalpy of activation (ΔH ‡ ) of 68.75 kJ mol −1 , entropy of activation (ΔS ‡ ) of −72.05 J K −1 mol −1 , and Gibb's free energy of activation (ΔG ‡ ) average of 97.08 kJ mol −1 . Based on the activation complex theory (ACT), the thermodynamic activation parameters indicated a nonspontaneous, endergonic, and endothermic process: ΔG ‡ > 0, ΔH ‡ > 0, and ΔS ‡ < 0, with estimated storage time of 149.82 d at 25 °C.

The emission properties of Ag NCs dispersed in a fluorophosphate glass have been studied. White light is generated under UV excitation due to the presence of a variety of Ag NCs with different sizes, emitting in the blue, green and red regions.

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The water loss and sugar gain modeling during the dehydration process is useful as a technique for predicting the operating conditions and the process time. The transfer of sucrose and fructooligosaccharides (FOSs) to melon and water to solution was modeled based on generalized form of Fick's second law for simultaneous diffusion and resolved by the finite element method using the software package COMSOL Multiphysics 3.2. The diffusion coefficients, the mass transfer coefficient and the Biot number were determined using the simplex optimization method by minimizing the percentage errors. The optimized main diffusion coefficients were 21.07 × 10 −11 m 2 /s for sucrose, 15.60 × 10 −11 m 2 /s for water and 8.96 × 10 −11 m 2 /s for FOS. The simulation results exhibited good fits to the experimental values, which validates the model predictive ability. The developed system for diffusion simulating water and solutes will enable control and modulation of the sucrose and FOS content in melon pieces. PRACTICAL APPLICATIONSThe use of functional sugars in fruits generates a new range of food taking into account the growing consumer market of these products. The study of processes involved in osmotic dehydration, as well as mass transfer simulation and modeling, is a useful predictive tool for the food industry, for assisting in the process time optimization among other variables involved.

0) with positive ∆H‡ values and positive and negative ∆S‡ values. The application of simplex centroid mixture design, using Ea as response, showed the optimised value of 174.46 kJ mol-1 for a mixture containing 33.33 and 66.67% of TBHQ and PG, respectively.]]>