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A series of tetrabutyl ammonium (TBA) salts of V-included Keggin-type polyoxoanions with W (TBA4PW11V1O40 and TBA5PW10V2O40) and Mo (TBA4PMo11V1O40 and TBA5PMo10V2O40) as addenda atoms were prepared using a hydrothermal method. These synthesized materials were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-Vis diffuse reflectance (DRS UV-Vis), thermogravimetric analysis (TGA), CHN elemental analysis (EA), inductively coupled plasma spectrometry (ICP-MS), and N2 physisorption techniques to assess their physicochemical/textural properties and correlate them with their catalytic performances. According to FT-IR and DRS UV-Vis, (PVXW(Mo)12−XO40)(3+X)− anions are the main species present in the TBA salts. Additionally, CHN-EA and ICP-MS revealed that the desired stoichiometry was obtained. Their catalytic activities in the liquid-phase aerobic oxidation of benzyl alcohol to benzaldehyde were studied at 5 bar of O2 at 170 °C. Independently of the addenda atom nature, the catalytic activity increased with the number of V in the Keggin anion structure. For both series of catalysts, TBA salts of polyoxometalates with the highest V-substitution degree (TBA5PMo10V2O40 and TBA5PW10V2O40) showed higher activity. The maximum benzyl alcohol conversions obtained were 93% and 97% using (TBA)5PMo10V2O40 and (TBA)5PW10V2O40 as catalysts, respectively. In all the cases, the selectivity toward benzaldehyde was higher than 99%.

Acacia melanoxylon and Acacia dealbata are two Australian species well acclimated in Chile, both wood species with an interesting industrial potential. In this work, has been studied kiln drying runs and the wood drying quality of the sawn wood of Acacia melanoxylon and Acacia dealbata during kiln drying at conventional temperatures.Eight tests of kiln drying to conventional temperatures are made, using a convective drying of 0,3 m3 of capacity. The experimental design includes as variable the species (A. melanoxylon an A. dealbata), the wood thickness (25 and 50 mm) and the cut-type (flatsawn-wood and quartersawn-wood). The wood drying quality on the basis of European and Chilean standards is evaluated.The results show that for a same thickness, both species A. melanoxylon and A. dealbata, in flatsawn and quartersawn-wood could be satisfactorily kiln dryied under a similar program of conventional temperatures. The wood drying quality is performed due to both species are free of collapse and they are an low transversal shrinkage., Entre las especies del género Acacias, la Acacia melanoxylon o aromo australiano y la Acacia dealbata o aromo chileno, son dos especies aclimatadas en Chile con un interesante potencial industrial. En este trabajo, se estudian programas de secado a temperaturas convencionales y la calidad de la madera seca de A. melanoxylon y A. dealbata.Experimentalmente son realizados 8 ensayos de secado a temperaturas convencionales, usando un horno de secado convectivo de 0.3 m3 de capacidad. El diseño experimental incluye como factores variables la especie (A. melanoxylon y A. dealbata), el espesor de la madera (25 y 50 mm) y el tipo de corte (tangencial y radial).Los resultados indican que para 25 o 50 mm de espesor, la A. melanoxylon y la A. dealbata, en corte radial y tangencial se dejan secar satisfactoriamente bajo un mismo programa de temperaturas convencionales. La calidad de la madera seca se ve favorecida por la carencia de colapso y la baja anisotropía de la contracción transversal.

Separata de: Boletín eclesiástico de la Diócesis de Segovia. N. 5 (1860), Tít. tomado do texto, Mención de responsabilidade tomada do comenzo do texto, O pé de imprenta consta no colofón