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61.
The surface of a slide glass (a specimen) with a notch was set in water at the focal region of a point-focus-beam lens to detect the AE (acoustic emission) signals radiating from cracks around the notch during a three point bending test. Output signals received by a transducer with a centre frequency around 50 MHz were amplified and A/D converted at a sampling rate of 200 MHz by a digital oscilloscope. The power spectra of the output signals were compared for the two cases with and without the weight used for the application of fracturing stress on the glass specimen. AE signals with a frequency range from a few megahertz to 100 MHz were successfully detected with this system for the glass specimen mounted on a small three point bending test bench.<> 相似文献
62.
V(z) curves are measured by a reflection-acoustic-microscope system in the nonscanning version. As for V(z) curves, leaky SAWs at the interface of water/solid are known to play an important role. In the letter, the effect of leaky SAW parameters, i.e. phase velocity and attenuation factor, has been numerically analysed on V(z) curves. The numerical calculation is performed for an acoustic line-focus-beam lens by introducing an idealised reflectance function where only a solution of leaky SAW is taken into consideration. It is clarified that the interval of dips and the shape of V(z) curves are strongly affected by the phase velocity and the attenuation factor, respectively. 相似文献
63.
Atsushi Sato Yuka Nakamura Toshikatsu Maki Kazuaki Ishihara Hisashi Yamamoto 《Advanced Synthesis \u0026amp; Catalysis》2005,347(10):1337-1340
Synergism in catalytic activity with the combined use of Hf(O‐i‐Pr)4 or Zr(O‐i‐Pr)4 and Fe(O‐i‐Pr)3 for direct esterification and a very simple method for their extraction with ionic liquids for their recovery and reuse are described. This Zr(IV) Fe(III) complex is an environmentally benign catalyst due to its high turnover number, extremely mild Lewis acidity, low toxicity, reusability, and commercial availability at low cost. 相似文献
64.
Myowa-Yamakoshi Masako; Kawakita Yuka; Okanda Mako; Takeshita Hideko 《Canadian Metallurgical Quarterly》2011,47(4):1042
In the present study, we investigated whether infants' own visual experiences affected their perception of the visual status of others engaging in goal-directed actions. In Experiment 1, infants viewed video clips of successful and failed goal-directed actions performed by a blindfolded adult, with half the infants having previously experienced being blindfolded. The results showed that 12-month-old infants who were previously blindfolded preferred to look longer at the demonstrator's successful actions, whereas no such preference was observed in 8-month-old infants. In Experiment 2, infants watched the same 2 actions when the adult demonstrator was not blindfolded. The responses of 12-month-old infants were the opposite of those observed in Experiment 1: They showed a preference for the failed actions. These findings suggest that previous experience influenced the subsequent perception of others' goal-directed actions in the 12-month-old infants. We favor the interpretation that the preference for the successful actions in the 12-months-old infants provided with blindfolded experience demonstrates the influence of perceptual experience on considering the visual status of others engaging in goal-directed actions. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
65.
Hiroki Akutsu Yuka Maruyama Jun-ichi Yamada Shin’ichi Nakatsuji Scott S. Turner 《Synthetic Metals》2011,161(21-22):2339-2343
An anionic weak acceptor, 2-sulfo-1,4-benzoquinone, has provided a new BEDT-TTF (bis(ethylenedithio)tetrathiafulvalene) salt (BEDT-TTF)2(2-sulfo-1,4-benzoquinone)·H2O. Single crystal X-ray analysis indicates that the unit cell has two crystallographically independent donor layers, one of which has a β″-type packing motif and the other being disordered. Population analysis and SQUID magnetometry suggests that non-β″-layer has an α?-type packing motif. The dual-layered salt shows metallic behavior with a metal–insulator transition at 90 K. 相似文献
66.
67.
Hiromi Yoshida Yumi Shougaki Yuki Hirakawa Yuka Tomiyama Yoshiyuki Mizushina 《Journal of the science of food and agriculture》2004,84(2):158-163
The lipids extracted from the kernels of pumpkin (Cucurbita spp) seeds of three cultivars were classified by thin layer chromatography into six fractions: steryl esters (SEs, 0.5–1.2%), triacylglycerols (TAGs, 92.7–93.4%), free fatty acids (FFAs, 2.9–3.5%), sn‐1,3‐diacylglycerols (1,3‐DAGs, 0.4–0.9%), sn‐1,2‐diacylglycerols (1,2‐DAGs, 0.7–0.9%) and phospholipids (PLs, 1.5%). Fatty acids derivatised as methyl esters were analysed by gas chromatography with flame ionisation detection. Molecular species and fatty acid distributions of TAGs, isolated from the total lipids in the kernels, were analysed by a combination of argentation thin layer chromatography (TLC) and gas chromatography. A modified argentation TLC procedure, developed to optimise the separation of the complex mixture of total TAGs, provided 11 different groups of TAGs, based on both the degree of unsaturation and the total chain length of fatty acid groups. With a few exceptions, SM2 (5.8–20.1%), S2D (8.8–11.2%), M3 (6.7–24.8%), SMD (6.8–16.7%), M2D (16.7–23.6%), SD2 (4.6–15.1%) and MD2 (4.9–18.6%) were the main TAG components. These results suggest that there are significant differences (P < 0.05) not only in fatty acid distributions of acyl lipids but also in molecular species of TAGs among the three cultivars. The differences in pumpkin cultivars could be appreciable, based on the distribution of molecular species in TAGs. However, pumpkin seed kernels could be utilised successfully as a source of edible oils for human consumption. Copyright © 2004 Society of Chemical Industry 相似文献
68.
Dioxins in a soil sample were measured using gas chromatography/resonance-enhanced multiphoton ionization/time-of-flight mass spectrometry coupled with different types of laser sources. The fourth-harmonic emission (266 nm) of a nanosecond Nd:YAG laser (1 ns) provided low ionization efficiency, especially for highly chlorinated dioxins/dibenzofurans (CDDs/CDFs). The ionization efficiency was improved using the fourth-harmonic emission (266 nm) of a picosecond Nd:YAG laser (4 ps), due to shorter singlet excited-state lifetimes. It was, however, difficult to efficiently ionize hepta-CDD and octa-CDD/CDF, because of their shorter lifetimes, which were induced by stronger spin-orbit coupling that led to efficient relaxation of the excited molecule to triplet levels. The ionization efficiency was substantially improved using the fifth-harmonic emission (213 nm) of the picosecond Nd:YAG laser (4 ps), in which the analyte molecule that was relaxed to triplet levels was efficiently ionized using a photon with sufficient energy for ionization, although the pulse energy obtained at 213 nm was only one-third of the pulse energy obtained at 266 nm. The limits of detection achieved for 17 toxic polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs) were 0.41-45 pg. The analytical instrument developed in the present study performed sufficiently well for the practical trace analysis of dioxins in soil samples. 相似文献
69.
Kinuyo Sodemoto Junya Yamahana Takeshi Echigo Chihiro Nishijima Yuka Shimada Makoto Inaoki 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(2):525-528
A 75‐year‐old Japanese man presented with pruritic blisters and macules on his trunk and extremities. He had been on hemodialysis for 4 years because of chronic renal failure, and in recent months, a polymethylmethacrylate membrane had been used for dialysis. After a change in dialysis membrane to a cellulose triacetate membrane, pruritic tense blisters developed on the extremities in combination with marked blood eosinophilia. Physical examination showed erythematous macules and tense blisters on the trunk and extremities. A biopsy specimen of an erythematous macule showed subepidermal vesicles and eosinophils that attached to the dermal–epidermal junction. Serum level of eosinophilic cationic protein was elevated. From clinical, histological, and immunological findings, a diagnosis of bullous pemphigoid was made. New blisters continued to erupt during the period in which the patient used the cellulose triacetate membrane dialyzer, and even after the use of clobetasol propionate. It resolved only after the patient came back to the use of a synthetic membrane dialyzer. We discontinued the use of clobetasol propionate, and neither bullous eruptions nor blood eosinophilia recurred. These observations suggest that cellulose membrane may be involved in the development of bullous pemphigoid through activation of eosinophils in the blood and the skin lesion, as in the present case. 相似文献
70.
Hiromi Yoshida Yuka Tomiyama Sayaka Kita Yoshiyuki Mizushina 《European Journal of Lipid Science and Technology》2005,107(5):307-315
Seed oils from five legume cultivars of Phaseolus vulgaris, grown in Japan, were extracted and classified by thin‐layer chromatography (TLC) into seven fractions: hydrocarbons (HC; 0.7–1.4 wt‐%), steryl esters (SE; 1.7–3.3 wt‐%), triacylglycerols (TAG; 33.8–45.9 wt‐%), free fatty acids (FFA; 0.6–1.5 wt‐%), sn‐1,3‐diacylglycerols (1,3‐DAG; 0.3–1.0 wt‐%), sn‐1,2‐diacylglycerols (1,2‐DAG; 0.4–1.2 wt‐%) and phospholipids (PL; 49.4–58.8 wt‐%). Fatty acids derivatized as methyl esters were analyzed by gas chromatography (GC) and a flame ionization detector. Molecular species and the fatty acid distribution of TAG isolated from the total lipids in the beans were analyzed by a combination of argentation‐TLC and GC. A modified argentation‐TLC procedure, developed to optimize the separation of the complex mixture of total TAG, provided 18 different groups of TAG, based on both the degree of unsaturation and the total length of the three acyl chains of fatty acid groups. SDT (3.2–4.2 wt‐%), M2T (3.8–5.0 wt‐%), D3 (4.8–5.9 wt‐%), MDT (8.0–13.9 wt‐%), D2T (12.5–15.8 wt‐%), MT2 (19.4–22.7 wt‐%), DT2 (17.8–23.5 wt‐%) and T3 (9.2–13.0 wt‐%) were the main TAG components. The dominant fatty acids of TAG were α‐linolenic (48.5–57.8 wt‐%) and linoleic (16.7–25.8 wt‐%) acids, with appreciable amounts of palmitic (8.3–13.2 wt‐%) and oleic (7.8–13.8 wt‐%) acids. The high content of α‐linolenic acid in the cultivars of P. vulgaris could very likely play a beneficial role in reducing the risk of coronary heart disease among the large populations consuming them in Japan. 相似文献