475 research outputs found

    Au-Cu/SBA(Ti) based catalysts for photocatalytic applications

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    Comunicación a congresoIn this work, it has been synthesized several Au and Au-Cu alloy photocatalysts supported on two different mesoporous supports: a non-commercial SBA-15 and a post-synthesis TiO2 modified SBA-15 (TiSBA-15), with which a high dispersion of TiO2 species have been achieved maintaining the SBA-15 structure. In addition, it has also been obtained highly dispersed Au nanoparticles confined in SBA-15 pore channels, as can be observed in Figure 1. The photocatalysts have been preliminary tested in the preferential CO oxidation in a H2-rich stream (CO-PROX) at room temperature and atmospheric pressure under simulated solar light irradiation. In spite of the very low gold and copper loading (1.5 wt% and 0.5wt% respectively), the catalysts resulted active and selective in the low temperature photo-CO-PROX.Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tec

    Role of Mo in catalysts based on noble metals in hydrodeoxygenation reactions

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    The use of bio-energy as a renewable alternative to fossil fuels is nowadays attracting more and more attention. The bio-fuel from biomass seems to be a potential energy substitute for fossil fuels since it is a renewable resource that could contribute to sustainable development and global environmental preservation and it appears to have significant economic potential1. The problem is its high oxygen content, which gives undesirable properties for combustion. To remove oxygen, catalytic hydrodeoxygenation (HDO) reactions are carried out. Monometallic Mo/Si, Pt/Si as well as bimetallic PtMo/Si catalysts were prepared and evaluated in the hydrodeoxygenation (HDO)reaction of dibenzofurane (DBF) as a model molecule in biomass derived bio-oil.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Flebotomíneos (díptera: psychodidae) en la periferia de santarém (pa). Estratificacion horizontal y factores agravantes para la transmisión domiciliar de leishmaniosis

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    Phlebotominae collections were performed with CDC-type luminous traps, intradomiciliarily (dormitory) and peridomiciliarily (animal shelters) placed, triying to get breeding places in the outskirts of Santarem city in Brazil. Three outlying neighborhoods of the city, where there was registration of autochthonous cases of leishmaniasis, were chosen: Jutaí, Diamantino and St. André. 9.926 Phlebotominae individuals were captured, and they were distributed in 15 species. The most abundant species were L. longipalpis (59,72%) and L. carmelinoi (35,47%). In Jutaí neighborhood the largest amount of Phlebotominae was captured (6.031 specimens), followed by Diamantino neighborhood with (2.390 specimens) and St. André with (1.505 specimens). The major number of individuals was observed during the rainy season (5.377) than in the animal shelters (4.549). In the horizontal stratification there was a significant reduction (p = 0,02) in the Phlebotominae fauna as the residual forest increased.Fueron realizadas colectas de flebotomíneos por medio de trampas luminosas tipo CDC, colocadas intradomiciliarmente (dormitorio) y peridomiciliarmente (abrigos de animales) procurando los criaderos en barrios periféricos de la ciudad de Santarém, Brasil, haciendo la búsqueda en los lugares en donde hubiese registro de casos autóctonos de leishmaniosis, fueran seleccionadas, las siguientes áreas de trabajo: Jutaí, Diamantino y Sto. André. Se capturaron 9.926 flebotomíneos, distribuidos en 15 especies. Las especies más abundantes fueron L. longipalpis (59,72%) y L. carmelinoi (35,47%). En el barrio de Jutaí fue capturada la mayor cantidad de flebotomíneos (6.031), seguido por el barrio de Diamantino (2.390) y Sto. André (1.505). Hubo mayor densidad de individuos en los meses de la estación lluviosa. En la estratificación horizontal hubo reducción significativa (p = 0,02) de la fauna de flebotomíneos, en la medida en que aumentaba la separación de la floresta residu

    Risky Decision Making Assessed With the Gambling Task in Adults with HIV

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    Decision making was assessed using a laboratory gambling task in 67 adults with the Human Immunodeficiency Virus (HIV+) and in 19 HIV-seronegative (HIV−) control participants. Neurocognitive test performance across several domains was also analyzed to examine potential cognitive mechanisms of gambling task performance. As predicted, the HIV+ group performed worse on the gambling task, indicating greater risky decision making. Specifically, the HIV+ group selected more cards from the “risky” or disadvantageous deck that included relatively large payoffs but infrequent large penalties. The control group also selected such risky cards but quickly learned to avoid them. Exploratory analyses also indicated that in the HIV+ group, but not in the control group, gambling task performance was correlated with Stroop Interference performance and long delay free recall on the California Verbal Learning Test, suggesting the role of inhibitory processes and verbal memory in the poorer gambling task performance in HIV. These findings indicate the usefulness of the gambling task as a laboratory tool to examine risky decision making and cognition in the HIV population

    Nanoestructuras de ceria-titania para fotodegradar azul de metileno con luz solar simulada

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    En los últimos años la protección ambiental y el uso de fuentes de energía renovables son dos objetivos principales en la investigación química. La energía solar se puede aprovechar para la degradación fotocatalítica de moléculas orgánicas contaminantes, hormonas o medicamentos, tanto en el aire, en el agua, como en las superficies, porque la luz solar es capaz de descomponerlas [1]. A pesar de la gran cantidad de aplicaciones fotocatalíticas de la titania (TiO2), fotocatalizador no tóxico, de bajo costo y muy prometedor [2], hay algunos factores críticos que limitan su fotoactividad. El principal es el valor de su salto de energía, que limita su uso como fotocatalizador en la región UV del espectro. Con el objetivo principal de extender su uso a la región visible del espectro, en literatura se ha propuesto el depósito de metales nobles en su superficie, modificaciones superficiales, así como el dopaje con iones de metales de transición o elementos de tierras raras. En este sentido, el uso de ceria (CeO2) ha atraído una gran atención debido a propiedades como su biocompatibilidad, inercia química así como su actividad en reacciones de oxidación, relacionada con la formación vacantes de oxígeno en su superficie [3]. Se ha comprobado que el sistema oxídico mixto CeO2-TiO2 es más fotoactivo que la titania pura debido a la disminución del salto de energía y a la mejora en la movilidad de los excitones. Este trabajo tiene como objetivo desarrollar fotocatalizadores basados en nanoestructuras de titania que sean activas en el visible, dopando la matriz de titania con cerio. Principalmente se pretende evaluar tanto el papel del cerio como la morfología del nanomaterial en la respuesta fotocatalítica bajo luz UV y solar.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Sensation Seeking and Visual Selective Attention in Adults with HIV/AIDS

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    The association between sensation seeking and visual selective attention was examined in 31 adults with the Human Immunodeficiency Virus (HIV). Sensation seeking was measured with Zuckerman’s Sensation Seeking Scale Form V (SSS-V). Selective attention was assessed with a perceptual span task, where a target letter-character must be identified in a quickly presented array of nontarget letter-characters. As predicted, sensation seeking was strongly associated (R2 = .229) with perceptual span performance in the array size 12 condition, where selective attention demands were greatest, but not in the easier conditions. The Disinhibition, Boredom Susceptibility, and Experience Seeking subscales of the SSS-V were associated with span performance. It is argued that personality factors such as sensation seeking may play a significant role in selective attention and related cognitive abilities in HIV positive adults. Furthermore, sensation seeking differences might explain certain inconsistencies in the HIV neuropsychology literature

    Ni-Doped Ordered Nanoporous Carbon Prepared from Chestnut Wood Tannins for the Removal and Photocatalytic Degradation of Methylene Blue

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    In this work, Ni-doped ordered nanoporous carbon was prepared by a simple and green one-pot solvent evaporation induced self-assembly process, where chestnut wood tannins were used as a precursor, Pluronic® F-127 as a soft template, and Ni2+ as a crosslinking agent and catalytic component. The prepared carbon exhibited a 2D hexagonally ordered nanorod array mesoporous structure with an average pore diameter of ~5 nm. Nickel was found to be present on the surface of nanoporous carbon in the form of nickel oxide, nickel hydroxide, and metallic nickel. Nickel nanoparticles, with an average size of 13.1 nm, were well dispersed on the carbon surface. The synthesized carbon was then tested for the removal of methylene blue under different conditions. It was found that the amount of methylene blue removed increased with increasing pH and concentration of carbon but decreased with increasing concentration of methylene blue. Furthermore, photocatalytic tests carried out under visible light illumination showed that purple light had the greatest effect on the methylene blue adsorption/degradation, with the maximum percent degradation achieved at ~4 h illumination time, and that the percent degradation at lower concentrations of methylene blue was much higher than that at higher concentrations. The adsorption/degradation process exhibited pseudo second-order kinetics and strong initial adsorption, and the prepared carbon showed high magnetic properties and good recyclabilityThis research was funded by Junta de Andalucía, Consejería de Transformación Económica, Industria, Conocimiento y Universidades. Project P20_00375. Partial funding for open access charge: Universidad de Málag
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