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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.

Highly ordered mesoporous iron oxide (α-Fe₂O₃) material has been successfully obtained from mesoporous silica template, KIT-6 (3-D Cubic Ia3d symmetry), through nano-replication method. The mesoporous α-Fe₂O₃ material thus obtained exhibits well-defined mesopores (2.7 nm in diameter), high surface area (148 m²/g), high pore volume (0.47 cm³/g) and crystalline frameworks. The morphology of the mesoporous α-Fe₂O₃ material is very uniform in spherical shape of which the average particle size is about 100 nm in diameter.

A highly efficient method for size reduction of nanoparticles has been reported. Ferroelectric lead zirconate titanate (PZT) particles were used as an example to indicate the working principle. The typical average particle size of PZT particles prepared by hydrothermal method is between 500 and 1000 nm. Through the application of high intensity focused ultrasound (HIFU) to the particles, the average size of the particles is reduced to as small as 10–20 nm. The crystalline structure of the treated particles remains according to the X-ray diffraction (XRD) profiles. Transmission electron microscopy (TEM) shows that the treated particles have identical morphology and size. The nonlinear effects of shock wave introduced by HIFU were studied, and the size reduction results were compared with those by ultrasonic cavitations. Finally, the possible reasons for less damage caused by shock wave were discussed.

NiAl nanosized powders were synthesized by pulsed wire discharge (PWD) using twisted Ni and Al wires with various number of turns (N_t). The X-ray diffraction (XRD) patterns indicated that the optimum conditions for synthesized NiAl nanosized powders were usage of a twisted Ni and Al wire with 0.4 turn/mm discharged in N₂ gas. For clarifying the dependence of N_t on the powder purity, waveforms of current, voltage and deposited energy during the discharges were measured. From the waveforms, deposited energy ratio until a voltage peak (K_p), which is an index to evaluate volume fraction of evaporated wire, was calculated. In low K_p conditions, nanoparticles with low composition ratio of Ni(C_Ni) and large particles with high C_Ni were frequently observed. This result indicated that the Ni wire had a high boiling point than that of Al so that unevaporated Ni remained as large liquid droplets in the discharge. Decrease of K_p was thought that the increase of N_t introduced lattice defects by plastic deformation to increase the resistance and to evaporate the wire partially. From the results above, a method to synthesize NiAl intermetallic compound nanosized powders by PWD was successfully developed using Ni and Al twisted wires. In addition, K_p turned out to be important in synthesizing single-phase nanosized powders.

Carbon nanotubes (CNTs) filled with metals can be used in capacitors, sensors, rechargeable batteries, and so on. Their interface significantly affects the properties of the composites. Here, we show that three kinds of interfaces between crystalline Ni and CNTs exist, namely, ordered, distorted, and disordered. They presented lattice states of Ni atoms near the interface, whereas the (111)_Ni plane was parallel to the CNTs' surface and appeared apart in a smaller or bigger angle. The coherent face-centered cubic (f.c.c)/hexagonal close-packed structure (h.c.p) boundary was formed between the crystalline Ni and CNTs at the ordered interface, in which the match was (111)_Ni//(0001)_Carbon. We suggested a dislocation model for the coherent interface. The model explained why the angle between (200)_Ni and the CNTs' inner surface was 52.9° rather than the theoretical value of 54.75°. The dislocation was formed to fit the coherent relationship. Thus, Ni lattice shrinkage occurred. Further study indicated that the formation mechanism of crystalline Ni in CNTs was through heterogeneous nucleation on the inner wall surface and growth of the crystal nucleus.

The technology of Lithium-ion battery (LIB) separator has become more and more mature. But there are still many problems that needed to be resolved. For example, its mechanical strength is low relatively, thermal stability is bad and the porosity and electrochemical performance are imperfect. This paper introduces modification of electrospinning LIB separator from the way of adding nanoparticles, including SiO₂, TiO₂, Al₂O₃ and copper titanate oxide, etc. And addition methods include dissolving in dispersant, dissolving in polymer solution, coating and in situ method. The modified membranes possess higher ionic conductivity which can reach to the level of 10${}^{-3}$s/cm.

Calcined and dispersible titanium-doped hydroxyapatite (Ti-HAp) nanoparticles at different [Ti/(Ca+Ti)] atomic ratios (0.3, 0.4, and 0.5) were prepared using an anti-sintering method. The Ti substitution ratios of the HAp structures in the feed of Ti-HAp preparation were approximately 80%. Ti-HAp nanoparticles were coated on polyethylene terephthalate (PET) sheets through polyacrylic acid graft-polymers. The PET substrate was almost completely covered with monolayer nanoparticles (over 95%). Antibacterial activity of coated Ti-HAp was calculated from the survival ratio of the bacteria, Staphylococcus aureus, after ultraviolet (UV) irradiation at 312 nm and 6.4 mW/cm² for 30 s. The number of S. aureus on the Ti-HAp coated substrate decreased by 43% compared to those on the original PET and normal HAp coatings as negative controls. The antibacterial activity of Ti-HAp coated substrate was, furthermore, no statistically difference with TiO₂ sheet as a positive control.

Herein, we report that self-assembled surface modification of 4-hydroxy thiophenol and gold nanoparticles imparted trititanate nanotubes (TiNTs) with stable, highly efficient hydrogen production and Photoelectrochemical (PEC) properties. After gold nanoparticles decoration, the modified TiNTs exhibited the photocurrent density of 232 $\mu$A/cm² at 0 V versus Ag/AgCl, with onset potentials ($V_{\mathrm{\text{op}}}$) of −0.4 V versus Ag/AgCl. Our process uses 4-hydroxy thiophenol to achieve control over the bond between gold particles and TiNTs, and improves the distribution uniformity of gold nanoparticles on the surface of TiNTs, which leads to above 90% Faradaic efficiency during 3 h water splitting reaction for hydrogen production.

Effects of the Co₃O₄ nanoparticle on the phase formation, microstructure and dielectric properties of barium titanate ceramics are investigated in this study. Co₃O₄-doped BaTiO₃ ceramics were prepared by the conventional mixed oxide method followed by normal sintering in air. Systematic studies of X-ray diffraction (XRD), scanning electron microscopy and dielectric spectroscopy with varying doping levels were performed. The cell parameters, tetragonality and crystallite size of doped ceramics also were calculated from XRD data. Results showed that the single phase of BaTiO₃ gave no evidence of unwanted peak forms in any of the samples. Cubic phase occurred after adding Co₃O₄ at 0.25 mol%. Various grain sizes and shapes were found in this system. Finally, adding Co₃O₄ in BaTiO₃ ceramics resulted in shifting of the Curie point to a lower temperature. The composition, x = 0.25, showed different dielectric behavior, which related to appearance of the cubic phase and fine grain microstructure.

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.