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51.
Koshi Takenaka Masayoshi Ichigo Taisuke Hamada Atsushi Ozawa Takashi Shibayama Tetsuya Inagaki 《Science and Technology of Advanced Materials》2014,15(1)
Magnetostructural correlations in antiperovskite manganese nitrides were investigated systematically for stoichiometric and solid solution Mn3Cu1?xAxN (A = Co, Ni, Zn, Ga, Ge, Rh, Pd, Ag, In, Sn or Sb). This class of nitrides is attracting great attention because of their giant negative thermal expansion, which is achieved by doping Ge or Sn into the A site as a relaxant of the sharp volume contraction on heating (spontaneous volume magnetostriction ωs) because of the magnetovolume effects. The physical background of large ωs and mechanism of how the volume contraction becomes gradual with temperature are central concerns for the physics and applications of these nitrides. An entire dataset of thermal expansion, crystal structure and magnetization demonstrates that the cubic triangular antiferromagnetic state is crucial for large ωs. The intimate relationship between ωs and the magnetic structure is discussed in terms of geometrical frustration related to the Mn6N octahedron and magnetic stress concept. The results presented herein also show that ωs depends on the number of d electrons in the A atom, suggesting the important role of the d orbitals of the A atom. Not all the dopants in the A site, but the elements that disturb the cubic triangular antiferromagnetic state, are effective in broadening the volume change. This fact suggests that instability neighboring the phase boundary is related to the broadening. The relation between the gradual volume change and the local structure anomaly is suggested by recent microprobe studies. 相似文献
52.
Toshiyuki Momma Hiroki Nara Shinpei YamagamiChika Tatsumi Tetsuya Osaka 《Journal of power sources》2011,196(15):6483-6487
Many efforts have been paid to realize the superior anodes for future Li batteries in either the dry Ar atmosphere or the dry air atmosphere. In this work, in order to clarify the effects of such atmospheres, the most reactive anodes of Li were freshly electrodeposited under the dry Ar or under the dry air condition. The Solid Electrolyte Interface (SEI) formed during the electrodeposition of Li anodes is revealed to have a different chemical composition and protective feature. The Li deposited under the dry air was revealed to have longer cycle life in the electrolyte than that deposited in Ar, even in the electrolyte containing ionic liquid. From the XPS results, the SEI formed in dry air is proved to be different from that formed in Ar gas atmospheres, that is, the SEI formed in dry air consists of Li2CO3 and Li nitride. In order to improve the performance of the anodes, the atmosphere for the initial preparation of the anode/electrolyte interface should be tuned. 相似文献
53.
Ryuta Shigefuku Hideaki Takahashi Hiroyasu Nakano Tsunamasa Watanabe Kotaro Matsunaga Nobuyuki Matsumoto Masaki Kato Ryo Morita Yousuke Michikawa Tomohiro Tamura Tetsuya Hiraishi Nobuhiro Hattori Yohei Noguchi Kazunari Nakahara Hiroki Ikeda Toshiya Ishii Chiaki Okuse Shigeru Sase Fumio Itoh Michihiro Suzuki 《International journal of molecular sciences》2016,17(9)
The progression of chronic liver disease differs by etiology. The aim of this study was to elucidate the difference in disease progression between chronic hepatitis C (CHC) and nonalcoholic fatty liver disease (NAFLD) by means of fibrosis markers, liver function, and hepatic tissue blood flow (TBF). Xenon computed tomography (Xe-CT) was performed in 139 patients with NAFLD and 152 patients with CHC (including liver cirrhosis (LC)). The cutoff values for fibrosis markers were compared between NAFLD and CHC, and correlations between hepatic TBF and liver function tests were examined at each fibrosis stage. The cutoff values for detection of the advanced fibrosis stage were lower in NAFLD than in CHC. Although portal venous TBF (PVTBF) correlated with liver function tests, PVTBF in initial LC caused by nonalcoholic steatohepatitis (NASH-LC) was significantly lower than that in hepatitis C virus (C-LC) (p = 0.014). Conversely, the liver function tests in NASH-LC were higher than those in C-LC (p < 0.05). It is important to recognize the difference between NAFLD and CHC. We concluded that changes in hepatic blood flow occurred during the earliest stage of hepatic fibrosis in patients with NAFLD; therefore, patients with NAFLD need to be followed carefully. 相似文献
54.
We propose a novel framework for processing a continuous speech stream that contains a varying number of words, as well as non-speech periods. Speech samples are segmented into word-tokens and non-speech periods. An augmented version of an earlier-proposed, cascaded neuro-computational model is used for recognising individual words within the stream. Simulation studies using both a multi-speaker-dependent and speaker-independent digit string database show that the proposed method yields a recognition performance comparable to that obtained by a benchmark approach using hidden Markov models with embedded training. 相似文献
55.
Masayoshi Sugawara Tetsuya Suzuki Atsushi Totsuka Masayasu Takeuchi Kunimasa Ueki 《Starch - St?rke》1994,46(9):335-337
The corn hull dietary fiber was decomposed into their components such as cellulose, hemicellulose-A, -B, -C, -other and lignin by the Siegel method, and their contents were 16%, 1%, 57%, 14% and 2%, respectivity. The components of ordinary corn fiber were insoluble in water, but several decomposed fractions were able to dissolved. The solubility in water of hemicellulose-B was well and of hemicellulose A was slightly, but other fractions were insoluble. Hemicellulose-A, -B, -C and -other fractions were made up of about 30% of arabinose and 50% of xylose. Uronic acid contents and solubility in water of each hemicellulose fraction were mutually related. 相似文献
56.
Tetsuya Yamada Keizi Suzuki Hirotaka Katuzaki Makoto Hisamatsu Takashi Komiya 《Starch - St?rke》1990,42(6):217-223
Native potato starch (moisture content 15%) was treated by twin screw extruder under four operating conditions with varying barrel temperatures (110°C–230°C). These modified starch samples were compared to native and drum-dried starch. Starch sample solution for gel chromatography was prepared by the three methods (acidic, alkaline, and neutral methods). They were subjected to gel chromatography on Toyopearl HW-75, and some difference was found among the three gel chromatographic patterns obtained from the same starch solution. This discrepancy among GPC patterns suggests formation of some types of anhydro-bonds between chains of amylopectin and or amylose in the extrusion process. Elevating barrel temperature increases degree of depolymerization. The size of fragments formed with the treatment is bigger than that of oligosaccharides but smaller than that of amylose. 相似文献
57.
The present study was aimed to investigate the cognitive enhancing and anti-oxidant activities of Inonotus obliquus (Chaga) against scopolamine-induced experimental amnesia. Methanolic extract of Chaga (MEC) at 50 and 100 mg kg (-1)doses were administered orally for 7 days to amnesic mice. Learning and memory was assessed by passive avoidance task (PAT) and Morris water maze (MWM) test. Tacrine (THA, 10 mg kg (-1), orally (p.o)) used as a reference drug. To elucidate the mechanism of the cognitive enhancing activity of MEC, the activities of acetylcholinesterase (AChE), anti-oxidant enzymes, the levels of acetylcholine (ACh) and nitrite of mice brain homogenates were evaluated. MEC treatment for 7 days significantly improved the learning and memory as measured by PAT and MWM paradigms. Further, MEC significantly reduced the oxidative-nitritive stress, as evidenced by a decrease in malondialdehyde and nitrite levels and restored the glutathione and superoxide dismutase levels in a dose dependent manner. In addition, MEC treatment significantly decreased the AChE activity in both the salt and detergent-soluble fraction of brain homogenates. Further, treatment with MEC restored the levels of ACh as did THA. Thus, the significant cognitive enhancement observed in mice after MEC administration is closely related to higher brain anti-oxidant properties and inhibition of AChE activity. These findings stress the critical impact of Chaga, a medicinal mushroom, on the higher brain functions like learning and memory. 相似文献
58.
The purpose of the present investigation was to test whether permanent skeletal muscle cells (rat L6 cells) could serve as
an in vitro model for α-tocopherol (αTocH) biodiscrimination studies. L6 cells were incubated in the presence of high density lipoprotein
(HDL), low density lipoprotein (LDL), and very low density lipoprotein (VLDL) labeled in the lipid moiety with either all-rac-or RRR-[14C]αTocH. These incubations were performed either in the absence or in the presence of exogenously added bovine lipoprotein
lipase (LPL) since skeletal muscle is one of the major expression sites of LPL in vivo. Time-dependent uptake studies (up to 24 h) in the absence of LPL have shown that equipotent doses of all-rac- and RRR-[14C]αTocH (1.36∶1) led to almost identical accumulation of the tracer, independent of the lipoprotein class used as αTocH carrier.
With regard to αTocH donor capacity, it appeared that HDL is the most potent αTocH donor, followed by LDL and VLDL. In the
presence of LPL, all-rac- and RRR-[14C]αTocH uptake was significantly enhanced (between two- and tenfold). Biodiscrimination studies using chiral high-performance
liquid chromatographic analysis with radiometric detection of the corresponding methyl ether derivatives on a Chiralcel OD
column have demonstrated that the 2S-and 2R-isomers of αTocH were taken up in a 1∶1 ratio by L6 cells independent of the absence or presence of LPL. In addition, we
have not observed biodiscrimination between the four 2R-isomers, i.e., there was no preferential accumulation of the RRR-isomer. These data suggest that L6 cells do not discriminate between different αTocH isomers and that the addition of endogenous
LPL significantly enhances the uptake of RRR- and all-rac-αTocH. 相似文献
59.
Masayuki Akiyama Masashi Tatsuzaki Tomomi Michishita Toshikazu Ichiki Masahiro Sumi Michio Ikeda Tetsuya Araki Yasuyuki Sagara 《Food and Bioprocess Technology》2012,5(5):1924-1938
To design a consumer-oriented package that complements the taste and aroma of ready-to-drink chilled-cup coffee beverages by using the food kansei model, the effects of the diameter and the color of drinking straws as well as the cognition terms of coffee on consumer sensory characteristics and preferences were investigated. Variance and factor analyses of the sensory scores for chilled-cup coffee with milk and sugar using straws of different diameters, as rated by consumer panelists, extracted two perceived factors (F1, contribution ratio 36.5%, and F2, 28.6%). A two-dimensional plot of the average F1 and F2 scores of 123 panelists showed that the perceived characteristics of the same taste and aroma varied according to the straw diameter. An image investigation of different straw colors and another sensory evaluation using “black,” “brown,” and “green” straws were also performed. A principal component analysis of the image data revealed that the sensory characteristics of coffee with milk and sugar were imaged from the straw color. The second evaluation suggested that the images of straw colors affected the sensory characteristics. In addition, cluster and multiple-comparison analyses of Internet research data from consumers regarding the cognition terms for coffee exhibited three clusters representing the cognitive characteristics of terms by consumers and by developers and the differences of attractiveness degree on the cognition terms due to the consumers’ personal attributes. These studies provide useful information for the development of packages of chilled-cup coffee beverages. 相似文献
60.
Tetsuya Nanba Asima Sultana Shouichi Masukawa Masaaki Haneda Junko Uchisawa Akira Obuchi Hideaki Hamada 《Topics in Catalysis》2009,52(13-20):1766-1770
Selective catalytic reduction of NO x by NH3 over Cu–FER and Cu–ZSM-5 in the presence of n-decane and SO2 was investigated. NO x conversion over Cu–ZSM-5 decreased in the presence of n-decane, owing to inhibition of the active sites by coke formation. In contrast, coke formation was negligible over Cu–FER, which maintained its NO x conversion activity even in the presence of decane. Coke formation was negligible over H–ZSM-5 and H–FER supports, which suggests that Cu species were involved in coke formation. Temperature-programmed reduction by H2 and electron spin resonance spectroscopy indicated that [Cu–O–Cu]2+ was probably the Cu species involved in coke formation over Cu–ZSM-5. 相似文献