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We investigated the impact of doping ion type on the performance of a ZnO-based ammonia gas sensor to show the capability of these ions to achieve high-performance gas sensing at room temperature. A sol-gel method was used to synthesize both doped and undoped ZnO nanostructures, while the gas sensor device was made by casting ZnO onto a glass substrate for a uniform thin film. Then Al electrodes were attached to the film. The characterization was carried out via field-emission scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, UV–vis, Pl luminescence, Brunnauer-Emmett-Teller, I-V characteristic, and gas sensor setup device. PL measurement shows an increase in green emission spectra with Ba ion shifting the peaks from VO to VO+and VO+to VO++states. The gas sensor test at room temperature greatly enhances performance for certain ions. The Ba ions greatly influence gas sensor performance, increasing the response to 24 compared to 5 for undoped ZnO. The room-temperature enhancement achieved by the Ba ions could open the way to investigate more effective dopants for NH3gas sensors.

Stainless steel 316L (SS316L) as a significant bio-material, their wires were used to support the PMMA matrix. Two simple and low-cost surface pretreatments for SS316L wires were performed to enhance denture impact strength: mechanical scratching (treating SS316L wires with SiC powder inside a rotating container) and electrochemical anodizing. Three mechanical scratching samples for different periods of 60, 90 and 120min were prepared. Anodizing technique conditions were: Ethylene glycol with perchloric acid as an anodizing solution, 15V supplying and graphite rod as an anode. Anodizing process involved three pretreating periods of 15, 20, and 30min. All the prepared samples had dimensions of 65 × 10 × 3 mm. SEM technique showed different morphology nature involved holes, scratches and pores with a density of 104/μm2and a crack length of 60μm. The PMMA reinforced with scratched stainless steel 316L wire surface for 120 min presented the highest impact strength value (42 kJ/m2) with (450.91%) increment. Anodizing samples showed a fluctuating behavior of samples with enhancing in the impact strength of anodizing wire for 20min of about 26.99 kJ/m2, which is still lower than that for scratched samples in average.