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The electrodialysis of gas evolving solutions may prove to be an important technology for many gasseparation applications, including CO 2 and SO 2 separation from mixed-gas streams. Progress on the use of electrodialysis for gas separation has been hampered by the increased resistance caused by gas bubbles on the surface of the electrodialysis membranes. This effect reduces the effective membrane surface area, causing increased voltages and reduced membrane lifetimes due to localized ''hot spots'' of high current density. To overcome this problem, we designed, constructed, and tested a bipolar membrane electrodialysis (BPMED) system designed to operate up to pressures as high as 20 atm. For given process conditions, operation at a sufficiently high pressure keeps all gas dissolved in solution, eliminating the problems caused by gas bubbles on the membrane surfaces. We performed CO 2 desorption from aqueous bicarbonate solutions, demonstrating that high pressures decrease the resistance, voltage, and energy of the desorption process. Our results demonstrate that at high current densities (139 mA cm À2 ), the CO 2 desorption energy from aqueous bicarbonate solutions under highpressure operation can be 29% lower than under ambient-pressure operation.

Short and medium‐chain fatty acids (SMCFAs) are known as essential metabolites found in gut microbiota that function as modulators in the development and progression of many inflammatory conditions as well as in the regulation of cell metabolism. Currently, there are few simple and low‐cost analytical methods available for the determination of SMCFA. This report focuses on SMCFA analysis utilizing CE with indirect photometric detection (CE‐IPD). A ribonucleotide electrolyte, 5’‐adenosine mono‐phosphate (5’‐AMP), is investigated as an IPD reagent due to its high molar absorptivity and dynamic reserve compatible with separation and detection of SMCFA. The operating parameters like the composition of organic solvent, millimolar concentrations of the complexing agent (alpha‐cyclodextrin), 5’‐AMP and non‐absorbing electrolyte (boric acid), as well as the applied voltage, are optimized for resolution, efficiency, and signal‐to‐noise ratio. A baseline resolution of all nine SMCFAs is achieved in less than 15 min. Additionally, the developed CE‐IPD method shows promising potential to identifying SMCFA in rat fecal supernatant. The presented analytical assay is simple, economical, and has considerably good repeatability. The intraday and interday RSD of less than 1 and 2% for relative migration time, as well as less than 14 and 15% for peak area, respectively, were obtained for SMCFA in fecal solution.

Amate (amatl) es un papel hecho a mano de México hechas por indígenas otomíes. Esta artesanía es hecha de corteza del árbol amate o jonote. Es originalmente desarrollado en los estados de Puebla, Hidalgo y Veracruz sobre todo en San Pablito, Puebla. Sin embargo, el papel amate se vende como fondo de las pinturas realizadas por artistas nahuas del estado de Guerrero. Las pinturas de papel amate son una combinación de tradiciones nahuas y otomíes. Si bien ha habido algunas innovaciones menores, el papel amate se sigue haciendo con el mismo proceso básico que se utilizó en el período prehispánico mediante la obtención de fibra de la corteza del árbol de amate clásico. Esto está afectando negativamente el ecosistema del norte de Puebla y obligando a los vendedores de corteza a la búsqueda de otras especies, por lo que es necesario hacer papel amate de forma más sostenible, incluyendo nuevos tipos de corteza de otras especies y subproductos de agroindustrias como arroz, café caña de azúcar, y otros tipos de fibra que tengan alta disponibilidad. El objetivo de este trabajo fue analizar y comparar las características químicas de la pulpa de café, como materia prima para papel amate de mayor calidad, que el producido con la corteza de otras especies. Los resultados mostraron que las características estructurales y químicas de la pulpa celulósica de pulpa de café presentaron facilidad de fabricación de papel, debido a sus propiedades de adhesión, formación y aglutinación de fibras similares a la alta calidad del producto final como el papel amate derivado de corteza del árbol.

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