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V2O5-TiO2 mixed oxide nanotube (NT) layers were successfully prepared via the one-step anodization of Ti-V alloys. The obtained samples were characterized by scanning electron microscopy (SEM), UV-Vis absorption, photoluminescence spectroscopy, energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (DRX), and micro-Raman spectroscopy. The effect of the applied voltage (30-50 V), vanadium content (5-15 wt %) in the alloy, and water content (2-10 vol %) in an ethylene glycol-based electrolyte was studied systematically to determine their influence on the morphology, and for the first-time, on the photocatalytic properties of these nanomaterials. The morphology of the samples varied from sponge-like to highly-organized nanotubular structures. The vanadium content in the alloy was found to have the highest influence on the morphology and the sample with the lowest vanadium content (5 wt %) exhibited the best auto-alignment and self-organization (length = 1 _m, diameter = 86 nm and wall thickness = 11 nm). Additionally, a probable growth mechanism of V2O5-TiO2 nanotubes (NTs) over the Ti-V alloys was presented. Toluene, in the gas phase, was effectively removed through photodegradation under visible light (LEDs, λmax = 465 nm) in the presence of the modified TiO2 nanostructures. The highest degradation value was 35% after 60 min of irradiation. V2O5 species were ascribed as the main structures responsible for the generation of photoactive e- and h+ under Vis light and a possible excitation mechanism was proposed. [ABSTRACT FROM AUTHOR]

In the present work, an archaeometric approach was used to investigate a sample of the functional tools collected from the Sąspów, Cracow district, and Wierzbica 'Zele', Radom district, flint mines sites. The investigated collection was completed on four non-use-worn specimens. The presence of areas enriched in iron (Fe) compounds has been noticed on the surfaces of all the specimens. They were analyzed by optical microscopy (OM) and scanning electron microscopy (SEM) coupled with an energy dispersive X-ray analysis system (EDS). Data sets were statistically evaluated using similarity analysis (DA, CA, MDS). The results indicated the variables that best discriminate the investigated flint artifacts collection in terms of either anthropoghenic or non-anthropoghenic nature of the residues preserved on their surfaces. [ABSTRACT FROM AUTHOR]

The aim of this work was to immobilize reduced graphene oxide (RGO) and titanium dioxide (TiO2) on the surface of selected fibrous structures. Textile fabrics made of cotton (CO) and polyamide (PA) were used as a carrier. The following modification methods were applied: coating for modification of PA and dip-coating for modification of CO. In the dip-coating method, no auxiliaries were used, which is a huge advantage. The RGO/TiO2 coated fabrics were characterized using several techniques: ultraviolet–visible (UV–VIS) spectroscopy, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The obtained results showed the immobilization of RGO and TiO2 on the fabrics. Raw fabrics absorb much less radiation than coated ones, which is associated with strong absorption of radiation by applied modifiers (RGO and TiO2). Photocatalytic activity of functionalized textiles was determined using aqueous phenol solutions. Phenol removal efficiency obtained for RGO/TiO2 coated CO and RGO/TiO2 coated PA was 51% and 46%, respectively. The hydroxyl radicals play a major role in the phenol photocatalytic degradation. The phenol removal efficiency in the fifth cycle was higher (about 14% and 8% for RGO/TiO2 coated CO and RGO/TiO2 coated PA, respectively) compared to the first cycle. [ABSTRACT FROM AUTHOR]

Purpose: More than half of the cavity restorations are replaced due to bacterial microleakage. A need for disinfection agents arises. Application of silver nanoparticles (AgNPs) may be beneficial, yet their impact on the adhesives' shear bond strength to dentin remains unknown., Methods: The aim was to assess the shear bond strength to dentin of different dental materials combined with AgNPs. Failure modes were also examined using SEM/FIB, SEM/EDS and endodontic microscopes., Results: The results showed no impact of AgNPs addition to dental materials in terms of shear bond strength to dentin. A change of the failure mode of the self-etch bonding system, Clearfil SE Bond, combined with AgNPs was observed. The new failure modes depended upon the order of application of the materials onto dentin., Conclusions: The microscopic evaluation of the samples showed the presence of AgNPs agglomerations gathered on the dentin's surface. AgNPs connection with self-etching dentin bonding system may have a serious clinical impact.