Abraham Garcia | Universidad Ana G. Méndez, Gurabo Campus (original) (raw)
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Papers by Abraham Garcia
Advances in Energy Research, 2014
Photocatalytic hydrogen generation by water splitting (H 2 O (l) →H 2 (g) +1/2O 2 (g)) has been s... more Photocatalytic hydrogen generation by water splitting (H 2 O (l) →H 2 (g) +1/2O 2 (g)) has been studied on photocatalysts based on Zn, Cd, Fe and Cu, synthesized by coprecipitation. Iron and copper nanoparticles were incorporated as cocatalysts to enhance the photocatalytic activity of the ZnCd solid solution. The effect of the different synthesis parameters (temperature, elemental atomic ratios, amount of Cu and Fe incorporated in the catalyst and calcination temperature) on the photocatalytic production of hydrogen has been studied in order to determine the best experimental synthesis conditions. The catalysts have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and BET. The experiments of photocatalytic water splitting were performed in aqueous solution of the photocatalysts previously dispersed in a soft ultrasound bath. The photocatalysts were irradiated under different lights ranging from 220 to 700 nm. The photocatalytic activity was found to be clearly dependent on the specific area of the photocatalyst.
CuO nanorods have been synthesized by a one-step hydrothermal approach. The particle size, morpho... more CuO nanorods have been synthesized by a one-step hydrothermal approach. The particle size, morphology and structure of the samples have been characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) surface area. The catalytic activity of CuO nanorods has been tested in three different reactions namely, the Huisgen cycload-dition reaction of benzylazide with phenylacetylene, the C-N cross coupling reaction between iodobenzene and aniline, and the oxidation reaction of CO to CO 2 . These results have been compared with those ob-tained using CuO nanowires (synthesized by thermal oxidation) and commercial CuO. CuO nanorods were found to be an excellent heterogeneous catalyst that can be recovered and reused for at least five cycles with almost no appreciable loss of activity.
UNU-MERIT Working Paper Series, 2010
This paper evaluates whether public support from innovation from the central government or the Eu... more This paper evaluates whether public support from innovation from the central government or the European Union spurs innovation in Austrian firms. The effect is estimated separately on R&D expenditures and the output side of innovation, measured by the share of total sales due to new or substantially modified products. A distinction is also made between products new to the firm and products new to the market. The analysis is based on the micro data from the third wave of Community Innovation Survey, CIS 3, covering the years 1998-2000. The effectiveness is estimated using a structural model explaining the determinants of various sources of government support and their effects on R&D and innovation output. Receiving central government support increases the intensity of R&D by 2.3 percentage points. EU support is never significant once national support is taken into account. Central government support yields a 2.5 percentage point increase in the share of new to firm innovative sales. When new to market product innovations are considered, central government support leads to a total effect on the share of new to market innovative sales of 3.4 percentage points.
Advances in Energy Research, 2014
Photocatalytic hydrogen generation by water splitting (H 2 O (l) →H 2 (g) +1/2O 2 (g)) has been s... more Photocatalytic hydrogen generation by water splitting (H 2 O (l) →H 2 (g) +1/2O 2 (g)) has been studied on photocatalysts based on Zn, Cd, Fe and Cu, synthesized by coprecipitation. Iron and copper nanoparticles were incorporated as cocatalysts to enhance the photocatalytic activity of the ZnCd solid solution. The effect of the different synthesis parameters (temperature, elemental atomic ratios, amount of Cu and Fe incorporated in the catalyst and calcination temperature) on the photocatalytic production of hydrogen has been studied in order to determine the best experimental synthesis conditions. The catalysts have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and BET. The experiments of photocatalytic water splitting were performed in aqueous solution of the photocatalysts previously dispersed in a soft ultrasound bath. The photocatalysts were irradiated under different lights ranging from 220 to 700 nm. The photocatalytic activity was found to be clearly dependent on the specific area of the photocatalyst.
CuO nanorods have been synthesized by a one-step hydrothermal approach. The particle size, morpho... more CuO nanorods have been synthesized by a one-step hydrothermal approach. The particle size, morphology and structure of the samples have been characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) surface area. The catalytic activity of CuO nanorods has been tested in three different reactions namely, the Huisgen cycload-dition reaction of benzylazide with phenylacetylene, the C-N cross coupling reaction between iodobenzene and aniline, and the oxidation reaction of CO to CO 2 . These results have been compared with those ob-tained using CuO nanowires (synthesized by thermal oxidation) and commercial CuO. CuO nanorods were found to be an excellent heterogeneous catalyst that can be recovered and reused for at least five cycles with almost no appreciable loss of activity.
UNU-MERIT Working Paper Series, 2010
This paper evaluates whether public support from innovation from the central government or the Eu... more This paper evaluates whether public support from innovation from the central government or the European Union spurs innovation in Austrian firms. The effect is estimated separately on R&D expenditures and the output side of innovation, measured by the share of total sales due to new or substantially modified products. A distinction is also made between products new to the firm and products new to the market. The analysis is based on the micro data from the third wave of Community Innovation Survey, CIS 3, covering the years 1998-2000. The effectiveness is estimated using a structural model explaining the determinants of various sources of government support and their effects on R&D and innovation output. Receiving central government support increases the intensity of R&D by 2.3 percentage points. EU support is never significant once national support is taken into account. Central government support yields a 2.5 percentage point increase in the share of new to firm innovative sales. When new to market product innovations are considered, central government support leads to a total effect on the share of new to market innovative sales of 3.4 percentage points.