Valorization of Brewery Wastes for the Synthesis of Silver Nanocomposites Containing Orthophosphate.

Brewery wastes from stage 5 (Wort precipitate: BW5) and stage 7 (Brewer's spent yeast: BW7) were valorized for the synthesis of silver phosphate nanocomposites. Nanoparticles were synthesized by converting silver salt in the presence of brewery wastes at different temperatures (25, 50, and 80 °C) and times (10, 30, and 120 min). Unexpectedly, BW7 yielded AgPO nanoparticles with minor contents of AgCl and Ag metal (Ag).

Effect of Microwave Treatment in a High Pressure Microwave Reactor on Graphene Oxide Reduction Process-TEM, XRD, Raman, IR and Surface Electron Spectroscopic Studies.

Reduced graphene oxide (rGO) was prepared by chemical reduction of graphene oxide (GO) (with a modified Hummers method) in aqueous solutions of hydrazine (NH), formaldehyde (CHO), formic acid (HCOH) accompanied by a microwave treatment at 250 °C (MWT) by a high pressure microwave reactor (HPMWR) at 55 bar. The substrates and received products were investigated by TEM, XRD, Raman and IR spectroscopies, XPS, XAES and REELS. MWT assisted reduction using different agents resulted in rGOs of a large number of vacancy defects, smaller than at GO surface C sp defects, oxygen groups and interstitial water, interlayer distance and diameter of stacking nanostructures (flakes).

Surface Study of FeO Nanoparticles Functionalized With Biocompatible Adsorbed Molecules.

Surfaces of iron oxide of ferrimagnetic magnetite (FeO) nanoparticles (MNPs) prepared by Massart's method and their functionalized form (f-MNPs) with succinic acid, L-arginine, oxalic acid, citric acid, and glutamic acid were studied by dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR-S), UV-vis, thermogravimetric analysis (TGA)/differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy (XPS), and reflection electron energy loss spectroscopy (REELS). The XPS analysis of elements and their chemical states at the surface of MNPs and f-MNPs revealed differences in chemical bonding of atoms, content of carbon-oxygen groups, iron oxide forms, iron oxide magnetic properties, adsorbed molecules, surface coverage, and overlayer thickness, whereas the Auger parameters (derived from XPS and Auger spectra) and elastic and inelastic scattering probabilities of electrons on atoms and valence band electrons (derived from REELS spectra) indicated modification of surface charge redistribution, electronic, and optical properties. These modified properties of f-MNPs influenced their biological properties.

Electron spectra line shape analysis of highly oriented pyrolytic graphite and nanocrystalline diamond.

The X-ray excited Auger electron spectroscopy (XAES), X-ray photoelectron spectroscopy (XPS) and elastic peak electron spectroscopy (EPES) methods were applied in investigating samples of nanocrystalline diamond and highly oriented pyrolytic graphite of various C sp(2)/sp(3) ratios, crystallinity conditions and grain sizes. The composition at the surface was estimated from the XPS. The C sp(2)/sp(3) ratio was evaluated from the width of the XAES first derivative C KLL spectra and from fitting of XPS C 1s spectra into components.