halarcon@ulima.edu.pe;acorzo@ulima.edu.pe;jcmorale@ulima.edu.pe

halarcon@ulima.edu.pe;acorzo@ulima.edu.pe

En el presente artículo presentamos el estudio realizado para la obtención de biopolímeros a partir del almidón de papa, para ser utilizado como empaque de alimentos, se modificó el almidón con ácido acético al 5% obteniéndose un polímero con un 61,76% de amilosa y 38,28% de amilopectina. Las pruebas de elongación y tracción mostraron que el almidón modificado presentó una mejor propiedad mecánica. Asimismo, se prepararon películas poliméricas donde se adicionaron aditivos al almidón modificado para lograr que el film mejore sus propiedades mecánicas y su textura, para ello se utilizó al Chitosan y Xathan en diferentes proporciones, determinándose una mejora de la propiedad mecánica del biopolímero. Esto fue corroborado con pruebas de elongación y tracción, obteniéndose valores del 33% y 8,47 N, respectivamente, las espectroscopias de infrarrojo y Uv-Vis realiza...

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In this paper we present the study to obtain biopolymers from potato starch, for use as a food packaging, starch with acetic acid was changed to 5% yielding a polymer with a 61.76% amylose and 38.28% amylopectin. The elongation and tensile tests showed that the modified starch presented better mechanical property. Also, additives were added to the films by modified starch for to make the film improved mechanical properties and texture for this to Xathan Chitosan and were used in different ratios, determining an improved mechanical property of the biopolymer were prepared. This was corroborated by elongation and tensile tests, yielding values of 33% and 8.47 N respectively and the Infrared spectroscopy -vis made Uv showing characteristic peaks biopolymers cellulose and good transmittance of 87%. All samples were obtained following the Taguchi method.

earroyo@ulima.edu.pe; halarcon@ulima.edu.pe

earroyo@ulima.edu.pe; halarcon@ulima.edu.pe

earroyo@ulima.edu.pe; halarcon@ulima.edu.pe

Thin films of zinc selenide (ZnSe) modified with Fe2+ and Cu2+ ions were obtained by the electrodeposition method and were studied as catalysts in the photoelectrocatalysis process for the degradation of methyl orange with active species of chlorine. The characterization of the synthesized material indicated the presence of microparticles with a size of 0.5 μm. The X-ray diffractograms showed the (111) and (220) planes of ZnSe, as well as the (111) plane of FeSe. Likewise, the Raman spectra showed characteristic vibrations of ZnSe. The presence of Zn, Se and Cu were corroborated by the EDS technique, in a non-stoichiometric proportion. The ZnSe and ZnSe-Fe films showed absorption maxima close to 545 nm, while the ZnSe-Cu film showed an energy reduction up to 595 nm. The compound ZnSe showed a good electrocatalytic activity with total discoloration in 45 min, when introducing Fe2+ and Cu...

En la presente investigación se sintetizaron películas de (WO3)n mediante la metodología Sol– Gel por técnicas de recubrimiento por inmersión ("dip coating") utilizando Na2WO como sal precursora para formar el ácido politúngstico ((WO3)n.nH2O), el cual por deshidratación formó el óxido ((WO3)n que se depositó en dos sustratos diferentes: acero inoxidable 316L y vidrio conductor FTO (Fluorine doped Tin Oxide), los cuales fueron depositados bajo las mismas condiciones experimentales y posteriormente sometidos a sinterización a 400 °C por lapso de 30 minutos para ambos casos.Se observó que la película de (WO3)n depositada sobre acero presentó mayor fotocorriente generada de 133 µAcm-2, frente a 29 µAcm-2 para la película de (WO3)n medida por voltametría cíclica en un potenciostato (AUTOLAB PGSTAT302N) frente a la película soportada en FTO. Las películas fueron carac...

In the present investigation (WO3 )n films were synthesized by Sol-Gel methodology by dip coating techniques using Na2 WO4 as precursor salt to form polytungstic acid ((WO3 )n . nH2 O), which by dehydration formed the oxide (WO3 )n that was deposited in two different substrates: 316L stainless steel and FTO (Fluorine doped Tin Oxide), which were deposited under the same experimental conditions and subsequently sintered at 400 ° C for a lapse of 30 minutes in both cases. It was observed that the film of (WO3 )n deposited on steel presented a greater photocurrent generated of 133 μAcm-2, compared to 29 μAcm-2 for (WO3 )n film measured by cyclic voltammetry in a potentiostat (AUTOLAB PGSTAT302N) against the FTO-supported film. The films were characterized using Fourier Transform Infrared Spectroscopy (FTIR) techniques, using the SHIMADZU IR PRESTIGE 21 FTIR spectrophotometer to recognize...

En la presente investigación se sintetizaron películas de (WO3)n mediante la metodología Sol– Gel por técnicas de recubrimiento por inmersión ("dip coating") utilizando Na2WO como sal precursora para formar el ácido politúngstico ((WO3)n.nH2O), el cual por deshidratación formó el óxido ((WO3)n que se depositó en dos sustratos diferentes: acero inoxidable 316L y vidrio conductor FTO (Fluorine doped Tin Oxide), los cuales fueron depositados bajo las mismas condiciones experimentales y posteriormente sometidos a sinterización a 400 °C por lapso de 30 minutos para ambos casos.

Multiple discs coated with hierarchically-organized TiO2 anatase nanotubes served as photoelectrodes in a novel annular photoelectrocatalytic reactor. Electrochemical characterization showed light irradiation enhanced the current response due to photogeneration of charge carriers. The pharmaceutical acetaminophen was used as a representative water micropollutant. The photoelectrocatalysis pseudo-first-order rate constant for acetaminophen was seven orders of magnitude greater than electrocatalytic treatment. Compared against photocatalysis alone, our photoelectrocatalytic reactor at <8 V reduced by two fold, the electric energy per order (EEO; kWh m-3 order-1 for 90% pollutant degradation). Applying a cell potential higher than 8 V detrimentally increased EEO. Acetaminophen was degraded across a range of initial concentrations, but absorbance at higher concentration diminished photon tra...