Original and effective syntheses of crystalline silver wires and saw bundles, using reduced Keggin polyoxomolybdovanadate (POM) as mediator and reducing agent, were performed in acetonitrile at room temperature; several parameters influencing the final silver 1D-structures, with micrometric length and nanometric thickness, were varied: the nature of the POM, silver salts, vanadium(iv) source an...

Zunyite [Al13Si5O20(OH,F)18Cl] possesses an unusual combination of an Al13O16(OH)24 Keggin structure and a Si5O16 pentamer unit. We used 19F, 27Al, 29Si MAS and 27Al MQMAS NMR spectroscopy of a series of samples with varying Al:Si and F:OH ratios to investigate the degree of atomic order in zunyite. The quadrupole coupling constant (CQ) and asymmetry parameter ( ) obtained from simulations of 2...

The selective oxidation of methoxy/methyl-substituted arenes to the corresponding benzoquinones has been first realized using aqueous hydrogen peroxide as a green oxidant, acid tetrabutylammonium salts of the γ-Keggin divanadium-substituted phosphotungstate [γ-PW10O38V2(μ-O)2]5- (I) as a catalyst, and MeCN as a solvent. The presence of the dioxovanadium core in the catalyst is crucial for the c...

Biodiesel synthesis from rice bran fatty acids (RBFA) was carried out using cesium exchanged 12-tungstophosphoric acid (TPA) catalysts. The physico-chemical properties of the catalysts were derived from X-ray diffraction (XRD), Fourier transform infrared (FTIR), temperature programmed desorption (TPD) of NH(3) and scanning electron microscopy (SEM). The characterization techniques revealed that...

The unusual behaviour of smectites, the ability to change volume when wetted (swelling) or dried (shrinking), make soil containing smectites very unstable and hazardous for the building industry due to foundation movement and poor slope stability. These macroscopic properties are dominated by the structural arrangement of its finest fraction. In this work we show utilisation of a new technique ...