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Abstract: Ni catalysts based on ternary mixed oxides, NiMAl (M = Mg, Ca, Zn) and NiMgN (N = La, Ce) were prepared by the coprecipitation method and characterized by N2-sorption measurements, TGA, XRF, XRD, H2-TPR and TEM. NiMAl (M = Mg, Ca, Zn) catalyst precursors exhibited a layered double hydroxide (LDH) structure, not observed in NiMgN (N = La, Ce) samples. NiMgAl mixed oxide exhibited well-stabilized nickel species needing high temperatures to be reduced (around 1100 K). The extent of Ni2+ reduction in the mixed oxides was improved with the replacement of Mg by Ca and Zn or Al by La and Ce. Catalysts were very active and selective in ethanol steam reforming although NiMgN (N = La, Ce) samples deactivate faster than NiMAl (M = Mg, Ca, Zn) having smaller Ni crystallites. In particular, the presence of Ca produced an important dispersing effect over the Ni species, favouring hydrogen production while keeping moderate coke formation. In the case of the reduced NiCaAl mixed oxide H2 selectivity values above 87 mol % were reached. [Copyright &y& Elsevier]

Abstract: A series of Ni catalysts supported on Al-SBA-15 mesoporous materials (Si/Al=20, 60, 140, 240, ∞) was prepared and tested in ethanol steam reforming. The catalysts were characterized by XRD, H2-TPR, NH3-TPD, TEM, ICP-AES, 27Al-MAS-NMR and N2-sorption measurements. It was found that the incorporation of Al atoms into SBA-15 structure is responsible for the formation of catalyst acid sites, an increase of the size of nickel species and stronger metal-support interaction between Ni and Al-SBA-15 carrier. Regarding ethanol steam reforming, catalysts with higher Al content keep ethanol conversion along time. However, Ni/Al-SBA-15 catalysts produce larger amounts of ethylene and coke, with slightly lower hydrogen selectivity than Ni/SBA-15. This is the consequence of ethanol dehydration in Ni/Al-SBA-15 acid sites, while ethanol dehydrogenation mechanism predominates in Ni/SBA-15 catalyst. [Copyright &y& Elsevier]

Abstract Proteomics experiments typically involve protein or peptide separation steps coupled to the identification of many hundreds to thousands of peptides by mass spectrometry. Development of methodology and instrumentation in this field is proceeding rapidly, and effective software is needed to link the different stages of proteomic analysis. We have developed an application, proteogest, written in Perl that generates descriptive and statistical analyses of the biophysical properties of multiple (e.g. thousands) protein sequences submitted by the user, for instance protein sequences inferred from the complete genome sequence of a model organism. The application also carries out in silico proteolytic digestion of the submitted proteomes, or subsets thereof, and the distribution of biophysical properties of the resulting peptides is presented. proteogest is customizable, the user being able to select many options, for instance the cleavage pattern of the digestion treatment or the presence of modifications to specific amino acid residues. We show how proteogest can be used to compare the proteomes and digested proteome products of model organisms, to examine the added complexity generated by modification of residues, and to facilitate the design of proteomics experiments for optimal representation of component proteins.