Annealing Behaviors of Al and Al-Mg-Si Alloy: A Real-Time Synchrotron X-ray Scattering Study.

We have studied the annealing behaviors of pure Al (Al-1050) and Al-Mg-Si alloy (Al-6061) with plate-type using a real-time synchrotron X-ray scattering in vacuum. At room temperature (RT), the crystal domain size of Al phase in the Al-Mg-Si alloy was small as 70 nm, compared to that in the pure Al, 142 nm. The crystal Al phase in the Al-Mg-Si alloy has more thermal stability than that in the pure Al.

Oxidation Behaviors of Aluminum Nanopowders with Different Particle Sizes: A Real-Time Synchrotron X-ray Scattering Study.

We have studied the oxidation behaviors of aluminum (Al) nanopowders with different particle sizes using a real-time synchrotron X-ray scattering during annealing in air. The Al nanopowders with small particle size of 78 nm at room temperature (RT) were a single crystal. The surface of the nanopowders was first oxidized to amorphous Al oxide near 450 °C, and then crystallized to γ-Al₂O₃ phase at 550 °C.

Sintering Behaviors of Au Nanopowders with Different Particle Sizes: A Real-Time Synchrotron X-ray Scattering Study.

We have studied the solid-phase sintering behaviors of Au nanopowders with different particle sizes using real-time synchrotron X-ray scattering and field-emission scanning electron microscopy (FESEM) experiments in air. Au powders with large particle size of 173 nm at room temperature showed a defect-free crystal domain size of 47 nm. Most of these powders showed multiple grains within the particle.

Oxidation Behaviors of Co, Cr, and Ni Nanopowders: A Real-Time Synchrotron X-ray Scattering Study.

We have studied the oxidation behaviors of Co, Cr, and Ni nanopowders for applications in biomedicine using a real-time synchrotron X-ray scattering in air. The Co nanopowders have a crystal domain size of 70 nm at room temperature (RT). The surface of the Co nanopowders was oxidized to CoO phase at RT.

Phase Transformation of Se/(Cu,In,Ga)/Mo/Glass Thin Films: A Real-Time Synchrotron X-ray Scattering Study.

The phase transformation of Se/(Cu,In,Ga)/Mo/glass thin films during annealing in a vacuum on and off state was studied in a real-time synchrotron X-ray scattering experiment. The crystalline CIGS phase is a solid solution of crystalline CIS and CGS phases. The crystalline CIS phase was formed first at lower temperature.

High Characteristic Sr-Ferrite Magnetic Powders Made by New Direct-Spray Roasting.

We have studied the process of new direct-spray roasting; SrCO3 powders were directly added into the 12FeCl2 x 4H2O solution first, and then α-Fe2O3 powders with the particle size of 210-620 nm was made after spray roasting in the low temperature of 400-700 degrees C. The direct-spray roasting enables us to get the uniform mixing of α-Fe2O3 and SrCO3 powders, and to lower the calcination temperature of Sr-ferrite, compared to that of the conventional dry method. Also, the magnetic properties of the powders made by direct-spray roasting are very higher than that made by the dry method.

Thickness dependence of the crystallization of Au/glass ultrathin films.

The crystallization of Au/glass ultrathin films for surface plasmon resonance (SPR) biosensor has been studied using synchrotron X-ray scattering and field emission scanning electron microscope. In films thinner than 30 nm, crystallized Au grains with [111] preferred orientation were formed in the as-deposited amorphous precursor. In film with 58-nm thickness, however, Au (200) powder grains existed on top of the Au (111)-oriented grains near the interface.

On the nature of various growth facets at the interfaces of gold catalyzed-silicon nanowires.

Modified embedded atom method-molecular dynamics simulations have been performed to define the various growth facets at the interfaces of Au catalyzed-silicon nanowires (SiNWs). The interfacial growth facet of Au/SiNW on c-Si (111) surface has a single, planar interface, that grows parallel to the Si (111) planes. The interfacial growth facet on c-Si (211) surface has an asymmetrical, cone shape.

Novel fiber optic sensor probe with a pair of highly reflected connectors and a vessel of water absorption material for water leak detection.

The use of a fiber optic quasi-distributed sensing technique for detecting the location and severity of water leakage is suggested. A novel fiber optic sensor probe is devised with a vessel of water absorption material called as water combination soil (WCS) located between two highly reflected connectors: one is a reference connector and the other is a sensing connector. In this study, the sensing output is calculated from the reflected light signals of the two connectors.

Crystallization of Au-Si/glass thin film: a real-time synchrotron X-ray scattering study.

The crystallization of amorphous, Si-rich, Au28Si72/glass thin film was studied in real-time synchrotron X-ray scattering experiments. The amorphous film crystallizes first into Au and Si phases at a low temperature of 206 degrees C. At annealing temperatures above eutectic temperature (T(E) = 360 degrees C), the Au phase melts while the Si phase rapidly grows further.

Average BER analysis of SCM-based free-space optical systems by considering the effect of IM3 with OSSB signals under turbulence channels.

In this paper, we derive the average bit error rate (BER) of subcarrier multiplexing (SCM)-based free space optics (FSO) systems using a dual-drive Mach-Zehnder modulator (DD-MZM) for optical single-sideband (OSSB) signals under atmospheric turbulence channels. In particular, we consider the third-order intermodulation (IM3), a significant performance degradation factor, in the case of high input signal power systems. The derived average BER, as a function of the input signal power and the scintillation index, is employed to determine the optimum number of SCM users upon the designing FSO systems.