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In this study, fabricated amorphous chalcogenide Ge10Se70Bi20 thin films were irradiated with nitrogen (N+), argon (Ar+), hydrogen (H+) and oxygen (O+) ion beams. The compositions of the pure and irradiated films were investigated using X-ray diffraction, which confirmed the amorphous structures of the pristine and the irradiated Ge10Se70Bi20 thin films. The optical parameters such as optical bandgap, absorption edge, Urbach energy, Tauc parameter and extinction coefficient of the unirradiated and irradiated films were determined using ultraviolet/visible spectroscopy. The energy gap was found to reduce from 1.355 eV for unirradiated Ge10Se70Bi20 to 1.02, 0.73, 0.60 and 0.51 eV after irradiation with nitrogen, argon, hydrogen and oxygen ion beams, respectively. Meanwhile, the band tail of Ge10Se70Bi20, which is 0.12 eV, increased to 0.16, 0.40, 0.45 and 0.48 eV after irradiation with nitrogen, argon, hydrogen and oxygen ion beams, respectively. In particular, the conductivity increased by two orders after the pristine film had been exposed to an oxygen beam. The direct current electrical conductivity of the pristine film increased from 1.5 × 10−7 to 1.4 × 10−5 Ω−1 cm−1 after irradiation with an oxygen ion beam. Furthermore, the activation energy and Mott’s parameters of the original and irradiated Ge10Se70Bi20 films were deduced. The reported modifications of the optical and electrical parameters suggest the use of irradiated Ge10Se70Bi20 thin films in important applications – for example, optical data storage and optoelectronic devices.

This paper is devoted to the interfacial aspects of the intraocular behavior, migration and distribution of commonly injected ophthalmic drugs in eyes filled with medical-grade 1300 cSt silicone oil used as a retinal tamponade agent. Novel in vitro and ex vivo models were created for studying the physical properties of the retinal surface and interfacial spreading of the ophthalmic drugs over retinas. In vitro model experiments showed that the droplets of all tested drugs sank rapidly in the silicone oil to contact with the plasma-treated glass and then rapidly spread over the glass surface. In the ex vivo model, the migration phase was followed by contact with and rapid spread/absorption by the retinal interface. The wetting behavior of drugs under contact with the glass substrate and retinas was similar. The characteristic timescales of drug spreading, controlled by the viscous dissipation, were close. All tested drugs migrated to the retinal surface and rapidly spread across the retinal surface. This suggests that intravitreal drugs might be used effectively in eyes filled with silicone oil tamponade, as they rapidly migrate to and spread over the retinal surface.

Recently, there has been a surge of interest in adopting natural dyes to avoid the environmental difficulties connected with synthetic coloring compounds. This research focuses on extracting natural dyes from Butea monosperma plants and on developing sustainable dyeing methods for silk fabric. Natural colorants were extracted using an aqueous and an acidic extraction procedure, and silk fabrics were dyed with the extracts using mordanting with a variety of metal mordants and bio-mordants. The treatment of fabric and extracts was carried out using microwave (MW) irradiation. It was found that the bio-mordants have shown higher color strength than metallic mordant. It was also observed that the acacia and pine nut hull at 80°C and before dyeing pomegranate extract at 80°C and after dyeing of silk fabric at 40°C using bio-mordants gave higher color strength than metallic mordants. For comparative analysis, aluminum (Al) salt at 40°C, iron (Fe) salt at 60°C and tannic acid at 80°C gave acceptable results. The colorfastness characteristics were also found good to excellent. The bio-mordants not only provide the higher color strength and fastness properties, but these extracts have also shown an environmental friendly approaches. Scanning electron microscopy image and Fourier transform infrared spectroscopy analyses revealed the difference between irradiated and unirradiated silk fabrics. Therefore, it is recommended that MW rays and bio-mordants should be used in the natural dyeing of silk fabric to produce colorfast shades of acceptable strength.

The influence of the parameters of a copper substrate on wettability at different temperatures was studied experimentally and theoretically. It is known that water condensation on graphene leads to a change in the electrical properties and affects graphene sensor sensitivity. To date, there are no data on the effect of temperature on the surface properties of graphene synthesized on copper. It is shown for the first time that a change in the (111), (110) and (100) crystal orientations of copper leads to different structuring of water on copper and on the graphene layer. An increase in temperature alters the density of water distribution and the pattern of water structuring. The analysis of the influence of grain boundaries on graphene synthesis is given. A change in the size of defects is shown to alter the qualitative nature of roughness for copper and graphene. Various methods of roughness processing allow explanation of the inconsistency of existing works comparing the roughness of the metal and graphene coating. The roughness measurement serves to prove the authors’ previously proposed hypothesis about the local stratification of graphene and copper due to large surface defects. The results obtained are important for the development of graphene-based sensor technologies.

Radiative cooling materials can cool terrestrial objects without any energy input but are susceptible to rain wetting and dust contamination, which affects badly their cooling characteristics. Herein, this work fabricated a radiative cooling porous film with superhydrophobic self-cleaning properties using poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and poly(vinylidene fluoride) (PVDF). The PVDF-HFP/PVDF film consists of micropores with nanoparticles both inside and at the surface. The micro/nanostructures enhanced the scattering of solar light, which in combination with the infrared emissivity of both PVDF-HFP and PVDF polymers makes the film show excellent radiative cooling ability with a sub-ambient temperature drop of 16°C. The micro/nanostructures roughened the surface of the film, which in combination with the low surface energy property of both PVDF-HFP and PVDF polymers endows the film with superhydrophobic self-cleaning properties. The self-cleaning function defends the film from contamination and maintains sustainable radiative cooling for lasting applications. The integration of cooling and self-cleaning into a film paves the way for multifunctional and long-life radiative cooling materials.

The insufficient osteointegration between titanium (Ti) based dental implants and surrounding bone tissue under osteoporotic conditions, as well as implant-associated infections usually associate with dental implant failure. Gallium (Ga) has drawn increasing attention due to its antibacterial ability and pro-osteogenic property. Herein, we established a facile strategy to deposit gallium oxide (Ga2O3) nano-layer on titanium dioxide nanotube (TNT) arrays by magnetron sputtering. Both Ga2O3@TNT/50 W and Ga2O3@TNT/100 W specimens were prepared at different powers (50 W and 100 W), respectively, which all achieved a sustained release of Ga3+ ion for over 14 days. In vitro results showed that Ga2O3@TNT/50 W sample has good biocompatibility and osteogenic activity, compared with TNT and Ga2O3@TNT/100 W samples. Moreover, both Ga2O3@TNT/50 W and Ga2O3@TNT/100 W samples possess potent antibacterial properties, due to the released Ga3+ ion. Furthermore, in vivo results indicated that the Ga2O3@TNT/50 W showed excellent in vivo antibacterial ability and promoted new bone formation effectively compared with TNT implants in an osteoporotic rat model with Staphylococcus aureus (S. aureus) infection. Therefore, such Ga2O3 deposition coating strategy provides a valuable guidance for the potential future development of Ga-doped dental implants and TNT based drug loading surfaces for clinical applications.

Alumina (Al2O3) remains one the most important engineering ceramic for industrial applications. In addition to the α phase, transition alumina phases have interesting characteristics. Controlling the obtained phase structure from alumina melt requires processes with extreme cooling rates and therefore limits the tailoring capabilities. This study investigates how the cooling rate of pure alumina affects its microstructural properties and phase structure in plasma-based processing. The paper reports phase changes in micron sized granulated alumina particles in high-temperature plasma spheroidization and compares the results to plasma sprayed alumina coatings. Both plasma processes involve melting of the material followed by subsequent rapid cooling. Direct comparison on the alumina phase transitions is obtained for the two methodically distinct processing routes, creating unique microstructures due to difference in their cooling rates.