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991.
Nagahara Y Nishida Y Isoda M Yamagata Y Nishikawa N Takada K 《Journal of oleo science》2007,56(6):289-295
In recent years, hair coloring gains popularity as a trend of consumer's hair care. This coloring frequently damages hair. In response to this, a new shampoo-base was developed for repairing hair damaged by coloring. The new shampoo-base was prepared by dispersing cationic assembly in a solution of amphoteric surfactants. The mixture of behenyl trimethyl ammonium chloride (C22TAC) and behenyl alcohol (C22OH) was applied as the cationic assembly, which are dispersed in amido propyl betaine laurate (LPB) solution. LPB, which behaves as an amphoteric surfactant, was used as the wash-base. It was verified from the results on the measurements of DSC, calorimeter polarization, cryo-SEM and X-ray diffraction that the cationic assembly has a crystalline structure in the LPB solution. The new shampoo-base was highly efficient to change the color-damaged hair from hydrophilic to hydrophobic. The friction level of the hair washed with the new shampoo-base recovered to the same state as that of healthy hair. The exfoliation of cuticle was reduced after washing with the new shampoo-base. 相似文献
992.
Isoko Takahashi Takanori Sugimoto Yasuo Takasu Mariko Yamasaki Yasutoshi Sasaki Youji Kikata 《Journal of Materials Science》2011,46(21):6841-6849
To improve the mechanical property of moldings made of steamed wood flour, layered wood moldings reinforced with steam-exploded
bamboo fiber was prepared. Setting the bamboo fiber weight fractions at 25, 50, and 75%, and number of layers at three-, five-,
and seven-layered wood moldings were prepared by compression molding. The results of tensile test showed that the tensile
strength as well as Young’s modulus increased along with the increase in the bamboo fiber fractions. Where the bamboo fiber
content was 75%, the tensile strength became approximately 3.8 to 5.8 times greater, and the tensile Young’s modulus became
approximately 2.5 times greater when compared to moldings of 100% wood flour. This fact shows that bamboo fiber is effective
to improve the mechanical property of wood moldings. In addition, the tensile strength also increased as the number of layers
increased. This result suggested that interfacial shear stress was produced between the layers of bamboo fiber and wood flour. 相似文献
993.
A carbon nanotube–enhanced SiC (CNT–SiC) coating was deposited on C/C composites to improve the oxidation resistance of C/C. The CNT–SiC coating was prepared by direct growth of CNTs on C/C surface at 700 °C followed by deposition of SiC using chemical vapor deposition at 1150 °C for 1 h. SiC was deposited on the CNTs as well as the interface between CNTs and C/C, making CNTs strongly rooted on C/C surface. The final CNT–SiC coating consisted of two layers: the CNT–SiC layer and SiC layer. In comparison to the SiC coating, the CNT–SiC coating showed fewer cracks and a better oxidation resistance because the CNTs reduce the stress in the coating caused by the mismatch of the coefficient of thermal expansion between C/C and SiC. 相似文献
994.
Juodkazis S Kohara S Ohishi Y Hirao N Vailionis A Mizeikis V Saito A Rode A 《Journal of nanoscience and nanotechnology》2011,11(4):2931-2936
We report on structural characterization of sapphire photomodified by voids of sub-wavelength diameter surrounded by amorphised regions formed after exposure by tightly-focused femtosecond laser pulses of 800 nm wavelength and 150 fs duration at the single and double-pulse irradiation inside crystalline sapphire. Regrowth of a crystalline phase near the edge between the amorphous and crystalline phases was observed by transmission electron microscopy (TEM) in the case of double-pulse-irradiated locations. Regions patterned by single-pulse-induced voids inside sapphire were characterized by synchrotron X-ray diffraction (XRD) technique. The XRD patterns indicate presence of an expanded phase of the host crystal. The origin of structural changes observed in TEM and XRD is discussed and is consistent with fast thermal quenching. 相似文献
995.
Yamashita K Yoshioka Y Higashisaka K Mimura K Morishita Y Nozaki M Yoshida T Ogura T Nabeshi H Nagano K Abe Y Kamada H Monobe Y Imazawa T Aoshima H Shishido K Kawai Y Mayumi T Tsunoda S Itoh N Yoshikawa T Yanagihara I Saito S Tsutsumi Y 《Nature nanotechnology》2011,6(5):321-328
The increasing use of nanomaterials has raised concerns about their potential risks to human health. Recent studies have shown that nanoparticles can cross the placenta barrier in pregnant mice and cause neurotoxicity in their offspring, but a more detailed understanding of the effects of nanoparticles on pregnant animals remains elusive. Here, we show that silica and titanium dioxide nanoparticles with diameters of 70 nm and 35 nm, respectively, can cause pregnancy complications when injected intravenously into pregnant mice. The silica and titanium dioxide nanoparticles were found in the placenta, fetal liver and fetal brain. Mice treated with these nanoparticles had smaller uteri and smaller fetuses than untreated controls. Fullerene molecules and larger (300 and 1,000 nm) silica particles did not induce these complications. These detrimental effects are linked to structural and functional abnormalities in the placenta on the maternal side, and are abolished when the surfaces of the silica nanoparticles are modified with carboxyl and amine groups. 相似文献
996.
Masakatsu Maeda Takaaki Sato Naoto Inoue Daisuke Yagi Yasuo Takahashi 《Microelectronics Reliability》2011,51(1):130-136
The present paper reports an anomalous microstructure formed at interfaces between Cu ribbons and Sn-deposited Cu plates by ultrasonic bonding. The interface consists of Cu-to-Cu directly bonded part and Sn-dispersed part. In the latter part, Sn is dispersed in the vicinity of the bond interfaces being retained as Sn. The formation process of the interfacial microstructure is discussed on the basis of detailed experimental analysis and theoretical analysis on the solid-state reaction at Cu/Sn interface. The theoretical analysis reveals three important points of the reaction. (1) The formation of Cu6Sn5 precedes that of Cu3Sn. (2) The incubation time for the formation of Cu6Sn5 changes discontinuously at the η/η′ transition temperature. (3) The incubation time for the formation of η′Cu6Sn5 is longer than that for ηCu6Sn5. 相似文献
997.
998.
999.
Syou Maki Chikako Udagawa Shotaro Morimoto Yoshifumi Tanimoto 《Microgravity science and technology》2014,26(2):125-130
We examined periodical oscillation phenomena that were observed during salt-water oscillator experiments under a small gravity condition. This condition was realized by situating a lower-density gadolinium chloride (GdCl 3) aqueous solution on a higher-density sodium chloride (NaCl) aqueous solution and applying a downward magnetic force. The GdCl 3 solution concentration was 0.15 mol/kg (density ρ=1.03×103 kg/m 3), and the NaCl concentration was varied to (A) 4.35 mol/kg (ρ=1.15×103 kg/m 3), (B) 3.79 mol/kg (ρ=1.12×103 kg/m 3), and (C) 2.49 mol/kg (ρ= 1.09×10 3 kg/m 3). The magnitude of magnetic flux density was varied from 0 to 4.00 T. As the magnetic flux density grew larger, the GdCl 3 solution was pulled downward by the magnetic force, and upward and downward flows were generated simultaneously at the orifice. These flows were accompanied by a periodical, locally thickened part. The thickened part was only observed when the magnetic force magnitude was small in cases (A) and (B). This flow pattern was not observed in case (C), in which a conventional salt-water oscillation was induced instead (C). In this paper we discuss new experimental results in which the oscillation cycles in cases (A) and (B) are strongly associated with the magnitude of the magnetic force and the density difference in the biphase solutions. 相似文献
1000.
Sato N Ishii K Satoh A Tanaka Y Hidaka T Nagaoka N 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2005,46(6):298-304
Fifty-two samples of broiled eels and broiled eel liver were analyzed for total mercury (total Hg) and methyl mercury. The mean concentrations of total Hg in broiled eels and broiled eel liver were 0.21 ppm and 0.10 ppm, respectively. Meanwhile, the mean concentrations of methyl mercury in broiled eels and broiled eel liver were 0.085 ppm and 0.039 ppm, respectively. The rate of methyl mercury to total Hg mainly ranged from 60 to 80% in broiled eels and from 35 to 65% in broiled eel liver. The total Hg concentrations of 2 samples of broiled eels and one sample of broiled eel liver exceeded the provisional regulation limit (0.4 ppm) of total Hg in fish in Japan. In these samples, the rates of methyl mercury to total Hg were lower than 20%. The muscles and the skin of broiled eels were measured separately. The ratios of skin to muscle concentration of total Hg and methyl mercury were mainly in the range from 1/10 to 1/4. The mean intakes of total Hg from broiled eels and broiled eel liver per individual were 24.6 microg and 3.1 microg, respectively. The mean intakes of methyl mercury from broiled eels and broiled eel liver per individual were 10.4 microg and 1.2 microg, respectively. 相似文献