With the objective of the browning controlling enzymatic in fruits, a sequence of experiments of enzymatic inhibition has been developed based on the system enzyme-sustrato-inhibitor (tyrosinase-pyrocatechol-inhibitor).The enzymatic activity of the tyrosinase has been substantially affected by the chelating inhibitors (EDTA), polymeric (chitosane) and enzymatic (papain). The inhibitory effectiveness of the papain has been attributed to its hydrolitic action on the active places 176G and 182E of the tyrosinase. An approach for the constant of Michaelis (Km at 25°C) has given the value of 2,0.

With the objective of the browning controlling enzymatic in fruits, a sequence of experiments of enzymatic inhibition has been developed based on the system enzyme-sustrato-inhibitor (tyrosinase-pyrocatechol-inhibitor).The enzymatic activity of the tyrosinase has been substantially affected by the chelating inhibitors (EDTA), polymeric (chitosane) and enzymatic (papain). The inhibitory effectiveness of the papain has been attributed to its hydrolitic action on the active places 176G and 182E of the tyrosinase. An approach for the constant of Michaelis (Km at 25°C) has given the value of 2,0.

This paper describes the synthesis of copper (0) nanopowder via MW and SCF. From CuSO4.5H2O, CuO was obtained and from this precursor copper Formate (II) was synthesized with MW radiation of a household oven at 30% of power, for a period from 4 to 6 hours. Then, keeping the same power, reflux system is changed by a buld distillation, where the powders of copper (0) are obtained by decomposition of the precursor which autocatalized at (368-436 °K),this reducing conditions allows the transformation from Cu (II) to Cu (0). Also high volumes of Cu(0) nanopowder, were obtained using ethanol as SCF, in a reducing atmosphere of H2, at Tmax 270° C and at Pmax 2425 psi in a microreactor PARR model 4560 (100mL, 200 bars) applied on the copper precursor. The products were characterized by UV, XRD, FTIR, FRX.

This paper describes the synthesis of copper (0) nanopowder via MW and SCF. From CuSO4.5H2O, CuO was obtained and from this precursor copper Formate (II) was synthesized with MW radiation of a household oven at 30% of power, for a period from 4 to 6 hours. Then, keeping the same power, reflux system is changed by a buld distillation, where the powders of copper (0) are obtained by decomposition of the precursor which autocatalized at (368-436 °K),this reducing conditions allows the transformation from Cu (II) to Cu (0). Also high volumes of Cu(0) nanopowder, were obtained using ethanol as SCF, in a reducing atmosphere of H2, at Tmax 270° C and at Pmax 2425 psi in a microreactor PARR model 4560 (100mL, 200 bars) applied on the copper precursor. The products were characterized by UV, XRD, FTIR, FRX.

This paper examines the nature of the multiple bond Chrome-chromium complexes of chromium (II) with carboxylate groups, evaluating the structural details and distances correlation between the metal-metal bond with their electronic properties as the energy of the molecular orbital (HOMO, LUMO), global indices (GAP, chemical potential, hardness and softness). Just as the relative effect of different types of carboxylate ligands, in the Chromium-Chromium link and modify properties. The computational calculations were using the semiempirical method (PM3), optimizing the geometry of the molecules. All this was done in the program Q-Chem, using the graphical interface Spartan. We conclude the existence of groups of molecules based on types of ligands, showing a correlation based on their electronic properties related Cr-Cr distance.

En el presente trabajo se estudió la naturaleza del enlace múltiple cromo-cromo, en complejos de cromo (II) con grupos carboxilatos, evaluándose los detalles estructurales y las correlación existente entre las distancias de enlace metal-metal con sus propiedades electrónicas, como la energía de los orbitales moleculares (HOMO, LUMO), índices globales (GAP, potencial químico, dureza y blandura). Así como el efecto relativo de los diferentes tipos de ligandos carboxilatos, en el enlace cromo-cromo y que propiedades modifican.Los cálculos computacionales se realizaron por el método Semiempírico (PM3), optimizando la geometría de las moléculas. Todo esto se realizó en el programa Q-Chem, utilizando la interface gráfica de Spartan.Concluimos la existencia de grupos moléculas en base a los tipos de ligandos, mostrando una correlación en base a sus propiedades electrónicas, r...