A nickel tetra-coordinated complex as catalyst in heterogeneous hydrogenation

The [NiCl₂(NH₂(CH₂)₁₂CH₃)₂] complex supported on γ-Al₂O₃ produces a catalyst which is considerably more active and sulfur-resistant for the hydrogenation of cyclohexene carried out in mild conditions than a conventional catalyst obtained from acid solutions of NiCl₂ and even than the same complex unsupported. As determined by XPS, the active species is the complex itself, which is stable under the reaction conditions. The higher sulfur-resistance is attributed to electronic and geometrical effects. The catalyst system is considerably more resistant to poisoning with thiophene than with tetrahydrothiophene. © 1998 SCI     

Identification of proteins of the yeast protein map using genetically manipulated strains and peptide-mass fingerprinting

In this study we used genetically manipulated strains in order to identify polypeptide spots of the protein map of Saccharomyces cerevisiae. Thirty-two novel polypeptide spots were identified using this strategy. They corresponded to the product of 23 different genes. We also explored the possibilities of using peptide-mass fingerprinting for the identification of proteins separated on our gels. According to this strategy, proteins contained in spots are digested with trypsin and the masses of generated peptides are determined by matrix-assisted laser desorption-ionization mass spectrometry (MALDI-MS). The peptide masses are then used to search a yeast protein database for proteins that match the experimental data. Application of this strategy to previously identified polypeptide spots gave evidence of the feasibility of this approach. We also report predictions on the identities of nine unknown spots using MALDI-MS.     

Optimal operation and hydro storage sizing of a wind–hydro power plant

Ambitious targets for renewable power production have been defined for the electric power systems in Europe. The accomplishment of these targets requires the increase in renewable energy production, namely from wind power generation. However, the intermittent nature of wind creates several problems to the power system operation and new approaches based on the combined use of wind power and energy storage technologies need to be developed. In this paper, the concept of the combined use of wind power production and hydro storage/production is exploited, through the development of an operational optimisation approach applied to a wind generator park with little water storage ability. The optimisation model defines the operational strategy to be followed for the hours ahead by a pump station and an hydraulic generator embedded in a wind/hydro pumping facility, using the Portuguese energy remuneration rules. The proposed methodology leads to considerable yearly profits for the wind generator production.     

Enzyme-assisted extraction of phenolic compounds and proteins from sugarcane bagasse using a low-cost cocktail from Auricularia fuscosuccinea

Sugarcane bagasse is the major by-product of the sugarcane industry, and it can serve as a substrate for biotechnological processes for obtaining value-added products. This study gave multiple adding values to sugarcane bagasse using it in two separate bioprocesses. Sugarcane bagasse was used as a substrate for enzymatic cocktail production from Auricularia fuscosuccinea LBM 244 and as a source of proteins and phenolic compounds. A. fuscosuccinea LBM 244 enzyme cocktail-assisted extraction, commercial enzyme assisted extraction and conventional extraction were compared. Enzymatic-assisted extractions released 557–827% more protein content than those at 0 h. A. fuscosuccinea LBM 244 enzyme cocktail released 50% and 30% phenolic compounds more than conventional and commercial enzyme extraction, respectively. These phenolic compounds were represented mainly by ρ-coumaric and ferulic acids. On top of that, the cost of the enzymes in enzyme-assisted extraction was reduced fourfold using the A. fuscosuccinea LBM 244 enzyme cocktail.     

Proteomic identification and physicochemical characterisation of paramyosin and collagen from octopus (Octopus vulgaris) and jumbo squid (Dosidicus gigas)

To perform improvements in food science, it is fundamental to understand the physicochemical properties of proteins since their interaction with other macromolecules plays an essential role in food systems. Collagen and paramyosin help in the maintenance of the matrix structure cells, the textural behaviour and the technical functionality of the protein concentrates; because of this, their identification and characterisation are necessary. Cephalopods species have shown differences in the distribution of its muscle fibres. The amino acid profile of jumbo squid showed a high content of glycine and hydroxyproline, while octopus showed a high content of acidic amino acids. The thermal profile of jumbo squid showed an endothermic transition at 117 °C, which octopus did not present. Moreover, the proteomic identification confirms the identity of paramyosin with 33% coverage to paramyosin from Dosidicus gigas and a 4% coverage to collagen type II from Sepia pharaonis on octopus and jumbo squid, respectively.     

8.2% pure selenide kesterite thin‐film solar cells from large‐area electrodeposited precursors

Cu₂ZnSnSe₄ solar cell absorbers are synthesized by large‐area electrodeposition of metal stack precursors followed by selenization. A champion solar cell exhibits 8.2% power conversion efficiency, a new record for Cu₂ZnSnSe₄ solar cells prepared from electrodeposited metallic precursors. Significant improvements of device performance are achieved by the application of two etching procedures and buffer layer optimization. These results validate electrodeposition as a credible alternative to vacuum processes (sputtering, co‐evaporation) for earth‐abundant thin‐film solar cell fabrication at low cost. Copyright © 2015 John Wiley & Sons, Ltd.     

High efficiency CIGS based solar cells with electrodeposited ZnO:Cl as transparent conducting oxide front contact

In this paper high efficiency (up to 15.8%) Mo/Cu(In,Ga)Se₂/CdS/i‐ZnO solar cells terminated with an electrodeposited ZnO:Cl window layer are reported. The optoelectronic properties of these cells are comparable to reference cells terminated with standard sputtered ZnO:Al. The use of an electrochemical step, a low cost and easily up‐scalable method, in the fabrication process of this type of solar cell, opens the possibility to lower their production price and make them more competitive. The optimization involves a soft annealing treatment (T ≤ 150°C) under atmospheric conditions after the electrodeposition which improves the transparency of the ZnO:Cl layers in the infrared region, the short circuit current and the fill factor of the I–V curve. These changes are related to the increase of one order of magnitude (up to 5 × 10² Ω⁻¹·cm⁻¹) of the lateral conductivity of the electrochemical layer due to an improvement of the free carrier mobility. Copyright © 2010 John Wiley & Sons, Ltd.