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71.
Hair lipid images, as visualized by argon sputter etching-scanning electron microscopy (ASE-SEM), reveal convex structures
with a stitch pattern (SP) at the cell membrane complex (CMC) in the transverse hair plane. Based on interindividual variation,
different features of the convex SP were classified into Types 0 to 4 with the corresponding scores 0 to 4. Observations using
hair fibers collected from 27 Japanese females revealed significant positive correlations between the scores and the levels
of exogenous lipids, which suggests that exogenous lipids internalized at the CMC predominantly constitute the convex SP.
Intraindividual variation with different levels of exogenous lipids among hair fibers derived from individual females may
be relevant to the uneven physicochemical properties of hair fibers on the scalp. Observations of 380 hair fibers collected
from Japanese (Mongoloid), German and American (Caucasoid) females aged 3 to 77 yr demonstrated similar age-related changes
in the lipid images, which represent an increase and then a decrease in levels of exogenous lipids with increasing age. This
suggests that age-related changes in exogenous lipids are attributable to alterations in sebum excreted during aging and that
this elicits age-related changes in physical parameters, which affect human hair texture. 相似文献
72.
Third-harmonic generation (THG) in air in tight-focusing conditions is presented. Variation of the pulse duration supplied optimal conditions for THG by femtosecond pulses that varied in the range 110-1300 fs. We show that this third-harmonic generation was caused by Kerr-induced phase variations of fundamental and harmonic beams. Various characteristics (laser intensity, focusing conditions, pulse duration, air pressure, etc.) of THG in air were analyzed to optimize this process. The THG conversion efficiency of 795 nm, 300 fs radiation was 1 x 10(-3). The harmonic radiation did not show considerable disruption of its spectral and spatial distribution in tight focusing conditions for intensities as high as 5 x 10(14) W cm(-2). 相似文献
73.
Nakanishi T Kozai H Morita M Murakami H Sagara T Ariga K Nakashima N 《Journal of nanoscience and nanotechnology》2006,6(6):1779-1785
Studies of the electrochemistry of Langmuir-Blodgett (LB) films of C70/artificial lipids including tridodecylmethylammonium bromide (3C12N+Br-, 1), didodecylphosphate (2C12PO4H, 2), and dioleoylphosphatidylcholine (DOPC, 3) and of LB films of a fullerene lipid (4) bearing triple alkyl chains on a C60 moiety on electrodes were carried out in aqueous media. Stable Langmuir monolayers of fullerene C70/artificial lipid composites and the fullerene lipid (4) were formed at the air-water interface and these monolayers were transferred onto electrodes as LB films. Here, we focus on the importance of cationic matrix lipid films to the facile electrochemistry of C70 embedded in a LB film of cationic lipids on an electrode in aqueous media. On the basis of the electrolyte dependence and the charge dependence of the matrix lipids, a possible electron-transfer mechanism of the C70/artificial lipid LB film-modified electrodes is presented. Electrochemistry of a LB film of 4 was also obtained in an aqueous medium. We demonstrate that the introduction of the chemistry of lipid bilayer membranes to the LB films of fullerenes guides us toward the construction of fullerene/lipid bilayer devices. 相似文献
74.
75.
Yoshihide Fujisaki Hiroto Sato Toshihiro Yamamoto Hideo Fujikake Shizuo Tokito Taiichiro Kurita 《Journal of the Society for Information Display》2007,15(7):501-506
Abstract— A flexible color LCD panel driven by organic TFTs (OTFTs) was successfully demonstrated. A pentacene OTFT with an anodized Ta2O5 gate insulator, which can be operated at low voltage, was developed. In order to improve the electrical performance of the OTFT, the gate insulator was surface treated by processes such as O2 plasma, UV light irradiation, and hexamethyldisilane treatments. The fabricated OTFT exhibited a mobility of 0.3 cm2/V‐sec and a current on/off ratio of 107 with a low operating drain voltage of ?5 V. A fast‐response‐time flexible ferroelectric LCD, which contains polymer networks and walls, was integrated with the OTFTs by using a lamination and a printing technique. As a result, color images were achieved on the fabricated panel by using a field‐sequential‐color method at a low driving voltage of less than 15 Vpp. 相似文献
76.
Seiji Kanazawa Hiroto Tanaka Toshikazu Ohkubo Marek Kocik Jen-Shih Chang 《Thin solid films》2007,515(9):4266-4271
In this study, the LIF detection of the hydroxyl (OH) radicals was performed in a nozzle-to-plane electrode system having an electrode gap of 30 mm during the steady-state positive streamer corona discharge at atmospheric pressure. For monitoring the ground-state OH radicals, OH transition [A2 Σ+(v′ = 1) ← X2Π(v″ = 0)] at 282 nm was used. The time relationship between the regular streamer coronas, laser pulse, OH fluorescence and laser-induced streamer was measured. The time dependence of OH radicals between the successive streamers was measured for the evaluation of OH dynamics when the discharge was in a steady-state condition. The two-dimensional OH distribution in the DC streamer corona discharge was observed. The obtained results showed that the ground-state OH radicals were generated mainly in the filamentary part of the streamers. It was found that LIF detectable amount of ground-state OH radicals stayed in the region where streamers propagate during the steady-state DC positive streamer corona in open air. 相似文献
77.
78.
Seiji Miura Hiroto Unno Tetsuro Yamazaki Satoshi Takizawa Tetsuo Mohri 《Journal of Phase Equilibria and Diffusion》2001,22(4):457-462
The present work reports the results of a reinvestigation of the γ liquidus and solidus temperatures of the Ni-Al system and the γ/Ni5Zr eutectic reaction temperatures in the Ni-Al-Zr system. In the Ni-Al binary system, it is found that the stability of the
Ni-rich γ solid solution phase is enhanced by small additions of Al with the melting temperature of the γ phase and that the melting temperature reaches a congruent maximum at a few at.% Al. The temperature of the eutectic reaction
L→γ+Ni5Zr in the Ni-Zr binary edge is confirmed to be 1196 °C by differential thermal analysis (DTA), rather higher than the value
reported previously. The reaction temperature increases with Al addition to reach or exceed 1206 °C, forming a “saddle point,”
then decreasing to reach 1187 °C or below by flowing into a ternary invariant reaction. These findings can be explained by
γ/liquid equilibrium in the Ni-Al binary system. 相似文献
79.
Takashi Ushikubo Mitsuhiko Kurashige Teruyo Koyanagi Hiroto Ito Yoshihisa Watanabe 《Catalysis Letters》2000,69(1-2):83-87
W–P mixed metal oxide catalysts are active and selective for the gas-phase hydration of ethene to ethanol. The activity and
selectivity of this catalytic reaction depend on the W/P atomic ratio. However, ethene conversion slightly decreases at higher
W/(W + P) atomic ratio. The selectivity for ethanol increases with the W/P atomic ratio and reaches the highest value (92%)
at W0.81P0.19Ox. The W0.81P0.19Ox catalyst is less active than the conventional H3PO4/SiO2 catalyst, but the activity is maintained for a long time without the supply of any catalyst components. The reaction temperature
does not affect substantially the rate of ethene hydration over the W0.81P0.19Ox catalyst. The H2O/ethene molar ratio of 0.4 is the most appropriate for both reaction rate and selectivity. The active species of W–P mixed
metal oxide are amorphous. But there is Keggin structure of W–P oxide species (PW12O40
3−) in the presence of steam. And the species are the active sites for the hydration of ethene, confirmed by in situ Raman spectroscopy.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
80.
The macrolayer thickness at critical heat flux has been determined based on the energy balance relation qCHF=ρlHfgδl·f, with measurements of the critical heat flux and the detachment frequency of vapor masses (coalesced bubbles) for various liquids at pressures from 0.05 MPa to 0.35 MPa for upward and vertical 20 mm diameter disk heaters. The macrolayer thickness correlation proposed in the fourth report of this series by Kumada and Sakashita [Trans. JSME, 58 (552) (1992), 2505] was modified with the data obtained in the present report. Macrolayer thicknesses at low heat fluxes for water and ethanol under atmospheric pressure were also measured while changing the orientation of the heating surface from vertical to downward. The measured macrolayers at low heat fluxes were thinner than those obtained from existing data measured by a probe method in the nucleate boiling region and agreed fairly well with the proposed correlation. © 1997 Scripta Technica, Inc. Heat Trans Jpn Res, 25 (8): 522–536, 1996 相似文献