Abstract

URENA SALAZAR, Elvia. Utilizando el video para promover la evaluación de pares y la autoevaluación en la clase de inglés. InterSedes [online]. 2022, vol.23, n.48, pp.228-245. ISSN 2215-2458.  http://dx.doi.org/10.15517/isucr.v23i48.49949.

Nanocellulose (NC) was obtained from palm oil rachis by combination of a chemical explosion method and mechanical rupture, which was functionalized with cholic acid (AC) and trietoxy(octyl)silane (TEOS) as functionalizing agents for determining the As3+ ion adsorption capacity from water. The nanocellulose functionalized it was characterized by infrared spectroscopy, thermal gravimetric analysis, scanning electronic microscopy and transmission electronic microscopy. Arsenic was measured by visible absorption according to molybdenum blue method. Nanofiber of cellulose was obtained with size than 19 – 24 nm, with which a functionalization of 25,96 % was achieved for NCAC and 20,50 % for NC-TEOS. The adsorption tests showed a 63,6 % removal of As3+ ion from the water using NC-AC and 22,6 % using NC-TEOS as adsorbents respectively, with which NC-AC showed a potential adsorption capacity material for ion As3+ from water.

Keywords : enseñanza del inglés; autoevaluación; video; comunicación oral; desempeño.

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