The crystal structure of ammonium polyuranates has been investigated. Powder X-ray diffraction (PXRD) has been employed to define single-phase samples within a series of synthesized compounds, which are further characterized by elemental analysis to ascertain the stoichiometry, revealing compositions of and . Analysis using extended X-ray absorption fine structure and vibrational spectroscopy has elucidated that both and possess a local structure similar to the metaschoepite─layered U(VI) oxohydroxide UO·2HO, but with HO and NH groups in the interlayers.
View Article and Find Full Text PDFThis article describes the one-pot microwave synthesis of silver nanoparticles (AgNPs) assisted with natural polyelectrolytes-humic substances (HS). The humic polyelectrolytes served both as chemical reductants for silver ions and as end-capping agents for AgNPs. Three commercially available sodium humates extracted from lignites and leonardite and one sodium fulvate isolated from natural brown water seeped through peat deposits were used in this study.
View Article and Find Full Text PDFThree-layer structures based on various multi-component films of III-V semiconductors heavily doped with Fe were grown using the pulsed laser sputtering of InSb, GaSb, InAs, GaAs and Fe solid targets. The structures comprising these InAsSb:Fe, InGaSb:Fe and InSb:Fe layers with Fe concentrations up to 24 at. % and separated by GaAs spacers were deposited on (001) -GaAs substrates at 200 °C.
View Article and Find Full Text PDFIdentification of multiphase inclusions in peridotite suggests that released carbon from a subducting slab can be stored as diamond+methane+magnesite in the overlying mantle wedge, achieving deep carbon cycling.
View Article and Find Full Text PDFThe current article describes the biological activity of new biomaterials combining the "green" properties of humic substances (HSs) and silver nanoparticles. The aim is to investigate the antioxidant activity (AOA) of HS matrices (macroligands) and AgNPs stabilized with humic macroligands (HS-AgNPs). The unique chemical feature of HSs makes them very promising ligands (matrices) for AgNP stabilization.
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