Narrow Results

Polycrystalline silicon carbide (P-SiC) films containing SiC nanoparticles and Er were prepared by r.f. reactive magnetron co-sputtering technique with SiC and Er targets on low-temperature silicon (111) and silicon dioxide substrates with the mixed gas of pure argon, methane, and hydrogen. Surface morphology and photoluminescence (PL) properties of them were measured by field-emission scanning electron microscope and Raman spectroscopy. The peak position, intensity, and the full width at half maximum (FWHM) of PL spectra were relevant with Er doping levels and deposition conditions.

PbS nanoparticle phosphors embedded in SiO₂ were synthesized at room temperature by the sol–gel method. The as-prepared SiO₂:0.134 mol% PbS nanoparticles were ground and annealed in atmosphere. Changes in the cathodoluminescence (CL) brightness and the surface chemical composition of the SiO₂:0.134 mol% PbS nanoparticle powders were investigated using a Fiber Optics PC2000 spectrometer for CL and Auger Electron Spectroscopy (AES) and X-ray Photoelectron Spectroscopy (XPS) for the surface chemical analysis. The chemical composition of the powders was analyzed by an energy-dispersive spectrometer (EDS). The CL intensity decreased when the powders were irradiated with a beam of electrons at 2 keV energy and a beam current density of 54 mA/cm² in an ultra-high vacuum chamber at oxygen (O₂) pressures ranging between 5 × 10^-8 and 2 × 10^-7 Torr for several hours. The O₂ Auger peak-to-peak height (APPH) decreased as the CL intensity decreased. XPS analysis on the degraded spot showed the development of characteristic SiO, SiO_x, and elemental Si peaks on the low-energy side of the SiO₂ peak. The desorption of O₂ from the surface, which resulted in a decrease in the CL intensity is attributed to the dissociation of SiO₂ into elemental Si and O₂ by the electron bombardment. The degradation was less severe at higher oxygen pressures. PbSO₄ was also formed on the surface during the electron beam degradation process.

Pure poly(vinylidene fluoride) (PVDF) membrane and PVDF composite membranes modified by three kinds of inorganic nanoparticles (SiO₂, Al₂O₃, and TiO₂) were made using a phase inversion method and characterized by pure water flux, retention efficiency of Bovine serum albumin (BSA), flux reduction coefficient, and scanning electron microscope (SEM). The results of flux reduction coefficient illustrated that PVDF membrane modified by nanoparticles had better antifouling property in the order of TiO₂, Al₂O₃, SiO₂. The Lewis acid–base properties of the nanoparticle materials were measured by inverse gas chromatography (IGC). The Lewis acid number, K_a, and Lewis base number, K_b, had the following order K_{a TiO2} < K_{a Al2O3} < K_{a SiO2}, and K_{b TiO2} > K_{b Al2O3} > K_{b SiO2}. The experimental results indicated that PVDF membrane modified by nanoparticles with relatively strong base exhibited excellent antifouling performance.

This paper presents the formation of graphene and its application to hydrogen sensors. In this work, the graphene was synthesized by annealing process of 3C-SiC thin films with Ni transition layer. The Ni film was coated on a 3C-SiC layer grown thermal oxided Si substrates and used extracts of the substrate's carbon atoms under rapid thermal annealing (RTA). Various parameters such as ramping speed, annealing time and cooling rate were evaluated for the optimized combination allowed for the reproducible synthesis of graphene using 3C-SiC thin films. Transfer process performed by Ni layer etching in HF solution and transferred graphene onto SiO₂ shows the I_G/I_D ratio of 2.73. Resistivity hydrogen sensors were fabricated and evaluated with Pd and Pt nanoparticles in the room temperature with hydrogen range of 10–50 ppm. The response factor of devices with the Pd catalyst was 1.3 when exposed to 50 ppm hydrogen and it is able to detect as low as 10 ppm hydrogen at room temperature.

This study outlines a drug delivery mechanism that utilizes two independent vehicles, allowing for delivery of chemically and physically distinct agents. The mechanism was utilized to deliver a new anti-cancer combination therapy consisting of piperlongumine (PL) and TRAIL to treat PC3 prostate cancer and HCT116 colon cancer cells. PL, a small-molecule hydrophobic drug, was encapsulated in poly (lactic-co-glycolic acid) (PLGA) nanoparticles. TRAIL was chemically conjugated to the surface of liposomes. PL was first administered to sensitize cancer cells to the effects of TRAIL. PC3 and HCT116 cells had lower survival rates in vitro after receiving the dual nanoparticle therapy compared to each agent individually. In vivo testing involved a subcutaneous mouse xenograft model using NOD-SCID gamma mice and HCT116 cells. Two treatment cycles were administered over 48 hours. Higher apoptotic rates were observed for HCT116 tumor cells that received the dual nanoparticle therapy compared to individual stages of the nanoparticle therapy alone.