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[EN] The aim of this study was to cast light on the effects of EconomasE™ (EcoE), a patented pre-mixture of nutritional additives consisting mainly of organic selenium (0.15 or 0.30 mg/kg feed; Se) combined with vitamin C (5 and 10 mg/kg feed; VC), compared to DL-α-tocopherol acetate (100 or 200 mg/kg feed; VE) dietary supplementation on rabbit performance and meat quality. In fact, the role of Se supplementation in the rabbit diet has not yet been elucidated in the literature and, more specifically, there are no studies on the possible synergistic action between organic Se compared with VE on lipids, fatty acids (FA) and the oxidative stability of two glycolytic muscles, longissimus lumborum (LL) and biceps femoris (BF). Two hundred and seventy New Zealand White rabbits were divided into five dietary groups of 54 rabbits each: 1) control (basal diet = BD; CTRL); 2) VE100 (BD + VE100 mg/kg); 3) VE200 (BD + VE200 mg/kg); 4) EcoE100 (BD + EcoE100 mg/kg); and 5) EcoE200 (BD + EcoE200 mg/kg). Neither of the antioxidant treatments affected growth performance, carcass traits or meat characteristics. Lipid and fatty acid contents were similar in LL and BF and not influenced by the dietary treatment. Meat oxidative stability was strongly improved by both antioxidants. These findings indicate that both EcoE and VE greatly improved the oxidative stability of LL and BF muscles at the dosage rates which, from an economic point of view, would normally be included in the formulation of feeds for rabbits., This study is part of a multidisciplinary research project funded by the Department of Veterinary Medical Science (University of Bologna, Italy). The authors thank Martini Group Spa (Budrio di Longiano, FC, Italy) who provided animals and feeds, and Alltech (Casalecchio di Reno, BO, Italy) who supplied the EcoE.

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A simple, microwave-assisted, strategy for producing Au/Ag concentrated sols by glucose reduction in water was developed. PVP stabilized Ag-Au bimetallic nanoparticles were characterized and their catalytic activity was studied in the reduction of 4-nitrophenol with NaBH4 as a probe reaction. The Ag-Au nanoparticles were prepared by first optimizing the synthesis of Au colloid and then carrying out the deposition of a silver shell. Microwave heating has been shown to provide more homogeneous particle nucleation and shorter synthesis time than traditional heating. Prepared Au, Ag and Au/Ag nanocrystals function as effective catalyst for the reduction of p-nitrophenol in the presence of NaBH4 otherwise unfeasible if only the strong reducing agent NaBH4 is employed

In the literature there are several studies concerning the use of gold-based catalysts for environmental applications. It has been recently reported that gold catalysts exhibit high performance in the deep oxidation of different molecules and are potentially capable of being employed in fuel cells for CO traces removal by preferential CO oxidation in H2-rich streams (PROX reaction) [1-2]. Several studies demonstrated the addition of an iron component to gold supported catalysts brings a beneficial effect in terms of enhanced activity, selectivity and resistance to deactivation. Thus, we designed catalysts containing iron stabilized gold nanoparticles with a controlled size and an intimate contact between gold and iron using bimetallic carbonyl clusters as precursors of the active phase [3]. Carbonyl metal clusters are, in fact, quite attractive since their chemistry is well developed, they can be prepared with different sizes and composition and be decomposed under very mild conditions.

A novel preparation method was developed for the preparation of gold/iron supported catalysts on TiO2 and CeO2 by employing bi-metallic carbonyl cluster salts. All prepared catalysts were fully characterized and tested in toluene and methanol total oxidation and in PROX reaction. The novel preparation method resulted in small gold metallic nanoparticles surrounded by highly dispersed amorphous iron oxide species on the supports. Results confirmed that FeOx species stabilize small Au particles. Partial encapsulation of gold atoms by iron species was also observed together with a strong interaction between gold and oxide species (both iron oxide and reducible supports). The presence of gold has been found to enhance the activity of iron oxide towards both the complete oxidation of toluene and methanol to CO2 and the PROX reaction. The extent of this positive effect resulted to be dependent on the adsorption properties of the organic molecule (toluene vs methanol), the support used and the interaction degree between FeOx and Au species. Moreover, CO preferential oxidation was found to strongly depend on Au particle size and surface oxygen reducibility, being related to the different oxide species which can be formed using different thermal treatment conditions or iron loadings over the support. The use of carbonyl clusters to synthesize bimetallic catalysts is a promising way to obtain iron stabilized gold nanoparticles and could find application even on support on which stabilization of gold is usually very difficult. In this way catalysts with highly dispersed active phase and an enhanced catalytic activity were obtained.

Coloured frits, obtained by sintering of ceramic pigments with a neutral vitreous phase and utilized in the decoration of ceramic tiles by dry screen printing, were selected and throughly characterized in order to evaluate their technological and colourimetric performances. A comparison between their peculiar properties and those shown by coloured frits, currently available on the market and obtained by different processing routes, revealed that sintered frits present more favourable physical performances as well as a greater colourimetric stability which make them the most suitable to be applied as dried powders by dry screen printing techniques