This work investigates the surface chemistry of the Ru/CeO catalyst under varying pretreatment conditions and during the oxidation of propane, focusing on both dry and humid environments. Our results show that the Ru/CeO catalyst calcined in O at 500 °C initiates propane oxidation at 200 °C, achieves high conversion rates above 400 °C, and demonstrates almost no change in activity in the presence of water vapor across the entire studied temperature range of 200-500 °C. Prereduction of the oxidized Ru/CeO catalyst in H significantly enhances its activity, though this enhancement diminishes at higher temperatures.
View Article and Find Full Text PDFUltrathin atomic layer deposited ceria films (< 20 nm) are capable of H2 heterolytic activation at room temperature, undergoing a significant reduction regardless of the absolute pressure, as measured under in-situ conditions by near ambient pressure X-ray photoelectron spectroscopy. ALD-ceria can gradually reduce as a function of H2 concentration under H2/O2 environments, especially for diluted mixtures below 10%. At room temperature, this reduction is limited to the surface region, where the hydroxylation of the ceria surface induces a charge transfer towards the ceria matrix, reducing Ce4+ cations to Ce3+.
View Article and Find Full Text PDFIncorporating nanoparticles into denture materials shows promise for the prevention of denture-associated fungal infections. This study investigates the antifungal properties of acrylic modified with microwave-sintered ZnO-Ag nanoparticles. ZnO-Ag nanoparticles (1% and 2.
View Article and Find Full Text PDFDesigning well-defined magnetic nanomaterials is crucial for various applications, and it demands a comprehensive understanding of their magnetic properties at the microscopic level. In this study, we investigate the contributions to the total anisotropy of Mn/Co mixed spinel nanoparticles. By employing neutron measurements sensitive to the spatially resolved surface anisotropy with sub-Å space resolution, we reveal an additional contribution to the anisotropy constant arising from shape anisotropy and interparticle interactions.
View Article and Find Full Text PDFEur Arch Paediatr Dent
December 2024
Aim: This study aimed to investigate the correlation between subjective pain threshold (SPT), daily pain recovery (PR) during the first postoperative week, and patient/surgical characteristics, while evaluating changes in SPT across multiple surgeries. Additionally, it assessed how perceived quality of life correlates with SPT and PR in adolescents undergoing lower third molar germectomy.
Methods: A prospective clinical study was conducted at the Paediatric Surgery Unit, Sapienza University of Rome, involving 51 patients aged 10-16 years undergoing lower third molar germectomy.