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The Intermittent Microwave Heating (IMH) assisted polyol method was used to disperse Pt nanoparticles on Vulcan XC-72 (C) and reduced Graphene Oxide (rGO) functionalized with [(η 6-C6H5OCH2CH2OH)RuCl2]2 (Ru-dim) and [(η 6-C6H4(CHMe2)Me)RuCl2]2 (Ru-cym). The nanocatalysts were labeled as Pt/CRu-dim, Pt/CRu-cym, Pt/rGORu-dim and Pt/rGORu-cym. Their catalytic activity was evaluated for the Methanol (MOR) and Ethanol Oxidation Reactions (EOR). 1H and APT 13C NMR characterization showed the coordination of arene ligands with ruthenium atoms, supporting the formation of Ru-dim and Ru-cym. Raman spectroscopy indicated that C and rGO preserve their graphitic band structure after functionalization. Functionalization of the supports resulted in the development of several surface chemical groups. The electrochemical characterization showed that: i) Pt/CRu-dim was the nanocatalyst with the highest catalytic activity for the MOR, demonstrating also a high performance for the EOR; ii) Pt/rGORu-cym showed a good electrocatalytic behavior for both reactions at more negative potentials, nevertheless delivering lower current densities (j). In terms of the organic molecule, higher j values have been obtained from the MOR, compared to the EOR. The results showed that these nanocatalysts can be considered as anode materials in Direct Alcohol Fuel Cells applications.

This work shows the study of two alumina materials synthesized from aluminum sulfate with different purity by hydrolysis-precipitation route. The main difference between the aluminum salt precursors was the lower cost of one of them which was due to the higher percentage of magnesium species as impurity. Both materials showed different mesoporous structure nano-fibrillar. The physic-chemical properties of these materials were studied by several characterization techniques as XRD, XRF, BET, 27Al MAS NMR, Pyridine adsorption FT-IR, FE-SEM/EDX, TEM and XPS. Furthermore, these materials were used as supports in the formulations of NiMo-based catalysts which were obtained by impregnation by the incipient wetness method of Ni and Mo salts in 3.3 and 15 wt. % respectively. The two NiMo/γ-Al2O3 sulfide catalysts were evaluated as catalysts in the reaction of hydrodesulphurization (HDS) of dibenzothiophene (DBT), using a high-pressure batch reactor at 350 °C and 3.1 MPa and time reaction of 5 h−1. The NiMo/γ-Al2O3 catalyst prepared by aluminum sulfate of low purity and lower cost exhibited the highest HDS efficiencies, 95 %, respectively, which were mainly ascribed to the presence of Mg (0.9 wt. %) as impurity.

Polyphenolic compounds are antioxidants compounds mainly present in plants and its concentrations may differ between the same species located at different growing points, since plants produce these compounds for protection against oxidative stress as a result of environmental factors that could affect them. The aims of present research, were: to determine the proximate composition; the polyphenolic compounds concentration and antioxidant activity in fruits of Lycium berlandieri, collected in the three locations of the municipality of Juárez, Chihuahua (Riveras del Bravo, San Isidro and San Agustín), to evaluate the effect of the inorganic nitrogen, alkalinity and salinity of the soil on the content of total phenolic and flavonoids compounds. The humidity content in the fruits of L. berlandieri ranged between 78.2 to 93.3%; the proximal composition of the fruit in dry weight indicated an ash content from 3.6 to 5.3%, fats from 0.9 to 6.7% protein from 9.0 to 15.4% and 75.2 to 85.7% total carbohydrates. In terms of polyphenolic compounds (in dry weight), fruits from San Agustín showed the highest concentration of these compounds, particularly in total phenols 12 mg EAG (P = 0.002) and 9.02 mg EC in flavonoids (P = 0.001). Results of soil analysis indicated that the soil of San Agustín showed the highest concentration of nitrates (88.51 mg kg-1) and a more saline soil (6.04 dS m-1). Overall, the results obtained allowed to attribute that the differences in concentration of polyphenolic compounds in the fruits of L. berlandieri, are related to the salinity of the soil and availability of nitrates, therefore the soil of San Agustín in Ciudad Juárez, Chihuahua it is optimal for the cultivation of L. berlandieri.

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Las comunidades vegetales micróf ilas y xeróf ilas en el norte de Chihuahua se desarrollan en condiciones de estrés climático y ambiental. Se considera que esta resistencia puede estar relacionada con la presencia de hongos micorrízicos de tipo vesículo arbusculares (HMVA). El objetivo de este trabajo fue relacionar el tipo de suelo con la presencia de HMVA en la rizósfera de las plantas de matorrales desérticos, como una posible respuesta a la resistencia de las plantas bajo condiciones ambientales extremas en las comunidades vegetales del área natural protegida (ANP) médanos de Samalayuca, Juárez, Chihuahua. Durante los meses de marzo a octubre de 2016, se realizaron dos muestreos dirigidos seleccionando cuatro puntos de muestreo con base en el tipo de comunidad vegetal registrada en campo. Los transectos fueron de 100 m, se generaron diez parcelas de 20 × 25 m2 en cada zona y para cada parcela se registró el número de individuos por especie vegetal. Los índices de Shannon, Simpson, Pielou y Morisita fueron utilizados para el estudio de las comunidades. Se tomaron submuestras de suelo de 500 g a una profundidad de 0 a 30 cm en cada sitio de muestreo. Los análisis físicos y químicos de suelo fueron pH, textura, conductividad eléctrica, porcentaje de humedad, nitrógeno mineral y fósforo extractable. La extracción y conteo de esporas de HMVA se realizó por medio de tamizado húmedo, decantación y centrifugación en solución sacarosa al 70%. Se determinaron tres tipos de comunidad vegetal: matorral inerme parvifolio, matorral mediano subinerme y matorral de médanos. La especie con mayor presencia y dominancia fue Larrea tridentata. Los suelos del área estudiada resultaron ser arenosos, alcalinos, con baja salinidad y contenido de nitrógeno y altos de fósforo. Los géneros de HMVA encontrados fueron: Gigaspora, Acaulospora, Glomus y Paraglomus. El análisis de correlación de Pearson indicó que no existe relación estadística signif icativa entre la cantidad de nitrógeno inorgánico con la densidad de las esporas de HMVA (r = 0.585), mientras que para el fósforo se detectó una signif icativa relación entre su concentración y la densidad de esporas (r = 0.987). La relación entre la cantidad de esporas y concentración de nutrientes del suelo demuestra que entre más bajo en nutrientes es menor el número de esporas, sin embargo, no se puede determinar directamente la resistencia de las plantas con la presencia de los HMVA.

Aerobic composting employing manual turning was evaluated by using the sludge produced by EMCALI EICE ESP’s Cañaveralejo wastewater treatment plant (PTAR-C). Compost (in 1,0 ton piles) consisted of sludge, a fixed proportion of bulking agent (10%) and amendment material. Sugarcane waste and solid organic (marketplace) waste were evaluated as amendment material using 20/80 and 40/60 weight/weight (amendment/sludge) ratios. Incorporating the amendment material improved the compost, being reflected in a faster start for the thermophilic phase, higher temperatures being maintained (>55°C) and better C/N ratio obtained in the compost in all treatments compared to the pile which had no amendment added to it. Incorporating the bulking agent improved sludge manageability during composting; the best combination was 54% sludge + 10% sugarcane bagasse + 36% liquid sugarcane waste.