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We report the generation of quasi-continuous-wave vacuum-ultraviolet (VUV) coherent light based on a Ti:sapphire laser with two successive frequency doubling stages. In the first stage, UV light at 399 nm with power of 1.1 W was obtained by exploiting an enhanced cavity. With a KBBF crystal as nonlinear material, quasi-continuous-wave VUV coherent light with power of about 25 mW at 199.5 nm and 4.7 mW at 193.5 nm were achieved through a single-pass SHG configuration, respectively, in the second stage.

We present measurements of the electrical resistivity ρ(T ) on high-quality single-crystalline CeNiSn under both hydrostatic pressure up to 1 GPa and uniaxial pressure up to 0.25 GPa. At ambient pressure, ρ(T ) along the orthorhombic a-axis (b-axis) shows two maxima at T L = 12 K (14 K) and T H = 74 K (40 K), respectively, which arise from the Kondo scattering of conduction electrons by the crystal-field ground state and excited states. With increasing hydrostatic pressure, both T L and T H increase linearly, and for P 0.8 GPa, the anisotropy in ρ(T ) for I a and I b almost vanishes as a result of increased hybridization between the 4f electrons and the conduction electrons. Under P a, both T L and T H in ρ(I b) increase similarly to under hydrostatic pressure. Under P c, however, the depression of T L in ρ(I a) and ρ (I b) suggests that the c-f hybridization in the crystal-field ground state is weakened in the a-b plane of CeNiSn.

The process of structural transformation of electrodeposited amorphous Ni-P alloy (hereafter referred to as a-Ni-P) was investigated. Heat-treated a-Ni-P sample films were etched and examined with an optical microscope and three kinds of characteristic crystalline patterns were observed. Using an x-ray diffractometer and a wavelength dispersive x-ray spectroscope, they were identified as NisP4 crystals containing Ni, NiP crystals containing Ni, and Ni~P and NiP2 crystals containing Ni. Their existence ratios were obtained by measuring the areas of the respective crystalline patterns which appeared on the surface of the sample films. In addition, the existence ratios in the process of quantitative growths and disappearances of the crystals during heat-treatment of electrodeposited a-Ni-P under constant heating rate were calculated as functions of temperature. It was confirmed that the results of calculations agree well with the quantitative measurements of crystal growths and disappearances in sample films.An a-Ni-P alloy film obtained through electrodeposition was first reported by Brenner et al. (1). Since then, it has been used to reinforce the film of, for example, magnetic hard disks, as a result of its hardness, corrosion resistance, and other advantageous properties (2-5).As it is, electro-or electroless deposited Ni-P alloy film is of amorphous structure (6). On the deposit reaction of electro-or electroless deposited amorphous Ni-P alloy (hereafter referred to as a-Ni-P) and the properties of deposited film caused by deposit conditions, a number of studies have been reported (5-8). Studies have been performed also on the transformation of a-Ni-P by heating and a change in properties accompanying the transformation, using such methods as x-ray diffraction, electron diffraction, thermal analyses including differential scanning calorimetry (DSC) and others (5,6,(9)(10)(11).The results of these studies show that a-Ni-P crystallizes by heating and various Ni=Py crystals (x and y represent atomic composition ratio) and Ni grow (5,6,9,12).Nevertheless, there has been no report on quantitative measurements of the existence ratios of the crystals in the process of electrodeposited a-Ni-P transformation by heattreatment at a constant rate of heating, as functions of temperature. We heated electrodeposited a-Ni-P sample films to various temperatures at a constant rate of heating, etched them, and observed with an optical microscope three kinds of characteristic crystalline patterns which grew or disappeared as the temperature changed. An x-ray diffractometer and a wavelength dispersive x-ray spectroscope (hereafter abbreviated to WDX) were used to identify these characteristic crystalline patterns. When the sample films were etched, crystals which grew in the sample films treated at various temperatures showed three kinds of characteristic patterns, and their existence ratios were obtained by measuring the areas of these patterns.In addition, the amounts of growths and disappearances of NixP, compounds and Ni growin...

Using a high-durability designed plasma electrode (PA), the plasma actuation effect on both a two-dimensional backward-facing step flow (standard model) and an arc-shaped three-dimensional backward-facing step flow (arc model) was investigated experimentally. First, we searched for plasma operation control conditions suitable for the two-dimensional backward-facing step flow by carrying out experiments using a medium-sized circulating wind tunnel. Next, using the natural-snow wind tunnel of the Hokkaido University of Science, we examined whether an AC-driven PA can control snowfall flow. It became clear for the first time that the amount of snow accumulation can be reduced by more than 20% when the PA is driven at a dimensionless frequency of fH/U = 0.32, where f is the pulsed modulation frequency, H is the step height, and U is the mainstream velocity, and the duty ratio D (the time ratio of PA_ON to the total time when controlled by the pulsed modulation frequency) is equal to 1.0%. It was also confirmed that by masking the arc-shaped electrode parallel to the mainstream and using only the part perpendicular to the mainstream of the PA electrode, the amount of accumulated snow could be reduced by up to 20%. It has become clear that high-durability designed plasma electrodes can control the snowfall flow and reduce the amount of accumulated snow.