The hydrodynamics and heat transfer characteristics of oil-in-water (O/W) emulsion droplets impinging on a hot stainless steel foil were investigated experimentally. A two-directional flash-photography technique was adopted to track the time evolution of the droplet shapes. The temperature history of the foil during the collision with the droplets was also measured using a high-speed infrared thermometer. The main objective was to investigate the effects of varying the solid temperature and oil concentration on the heat transfer characteristics. The foil temperature was varied from 140 to 470 °C, and the oil concentration in the O/W emulsion was varied to be 1, 5, and 15 wt%. The impact velocity of the droplets was 1.0 m/s, and the pre-impact diameter of the emulsion droplets was approximately 2.5 mm for oil concentrations of 1 and 5 wt%

We have studied photochemical deposition in a condensed phase. In the experiment, liquid silane ( SiH4) on a cryogenic substrate is irradiated with KrF and ArF excimer laser. The deposited film is characterized by Raman scattering, scanning electron microscopy, transmission electron microscopy and transmission electron diffraction. The film is composed of many rod-like crystalline silicon (c-Si) products. Their diameter and height are 400–500 nm and 500–700 nm, respectively. It is remarkable that the rod-like c-Si has grown on the cryogenic substrate. Therefore, we consider that the liquid-solid interface reaction plays an important role in the crystallization growth. In other words, the growth from the c-Si surface is necessary for crystallization. This technique solves general problems in photochemical vapor deposition techniques, such as deposition on the optical window, thermal damages of the substrate and the low deposition rate in the gas phase.

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