A fast optical profilometer

A simple optical profilometer is described for the measurement of surface profiles. The device is based on the use of a photodiode array that allows a fast examination of the surface and a high sensitivity. It also overcomes the randomness requirements which limit the use of optical devices working on angular diagram or speckle correlation measurements. Preliminary measurements of workpieces profiles are shown.     

Simple solvent-free preparation of dispersed composites and their application as catalysts in oxidation and hydrocarboxylation of cyclohexane

A simple and clean mechanochemical synthesis at room temperature was employed to prepare CuO-Fe₂O₃-CoCl₂ (100 nm scale), MoO₃-V₂O₅, CuO-CoCl₂, Fe₂O₃-CoCl₂, CuO-V₂O₅, Cu(CH₃COO)₂-V₂O₅, Cu(CH₃COO)₂-MoO₃ (1–100 μm scale) 3d metal based dispersed composites with different ratios of components using simple metal salts/oxides and multiwalled carbon nanotubes (CNT) or graphene oxide (GO) additives (CoCl₂-CNT, CoCl₂-GO). The thus prepared composite materials were characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), field emission gun scanning electron microscopy (FEGSEM), energy-dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM). XPS analysis revealed no metal redox change upon ball milling treatment, which however promotes metal hydroxylation.The catalytic activity of the prepared composites in the heterogeneous low power microwave-assisted oxidation of cyclohexane with aq. H₂O₂ at 30 °C was notorious with yields up to 31% and selectivity up to 94% towards cyclohexanol (upon treatment with PPh₃) for the CuO-CoCl₂-based material. The hydrocarboxylation of cyclohexane with CO, water and K₂S₂O₈ to produce cyclohexanecarboxylic acid bearing one more carbon atom at 60 °C is achieved with yields up to 17% for the reaction performed in the presence of the CuO-CoCl₂ catalyst. The clean CuO-CoCl₂ (1:2) catalyst preparation and the catalytic reaction (oxidation of cyclohexane) can be achieved in one-pot at low temperature, without any added organic solvent, and by using exclusively the mechanochemical energy input, with a marked 23% yield at 30 °C.     

On near dimensions in Steiner systems with parallelism and matroids

In this paper we introduce two near dimensions d_m, d in a 3-(v,q,1) Steiner system with parallelism S, and we shall prove that d(S) d_m(S)-1; moreover we provide examples of matroids, starting from particular Steiner systems with parallelism.     

Big data analytics: an aid to detection of non-technical losses in power utilities

Computational Management Science - The great amount of data collected by the Advanced Metering Infrastructure can help electric utilities to detect energy theft, a phenomenon that globally costs...