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排序方式: 共有854条查询结果,搜索用时 15 毫秒
841.
Takayuki Kobayashi Kazunori Sumiya Yoshinori Fukuba Masaki Fujie Takayuki Takahagi Kohji Tashiro 《Carbon》2011,(5):1646-1652
The Raman band shift has been measured under tension for carbon fiber (CF) monofilaments of different structural heterogeneity as characterized by a synchrotron micro-beam X-ray diffraction measurement. The apparent Raman band shift factor or the band shift caused by an application of bulk tensile stress 1 GPa was found to be larger for the CF fiber with the higher modulus or the sample with the harder skin part. In order to interpret the observed Raman shift data concretely, a complex mechanical model consisting of parallel array of skin and core parts has been proposed as a temporary model, which allows us to understand the structure–mechanical property relationship of the carbon fiber monofilament in a semi-quantitative manner. 相似文献
842.
Kunihiro Hasegawa Ryo Takata Hiroki Nishikawa Hirayuki Enomoto Akio Ishii Yoshinori Iwata Yuho Miyamoto Noriko Ishii Yukihisa Yuri Chikage Nakano Takashi Nishimura Kazunori Yoh Nobuhiro Aizawa Yoshiyuki Sakai Naoto Ikeda Tomoyuki Takashima Hiroko Iijima Shuhei Nishiguchi 《International journal of molecular sciences》2016,17(9)
We aimed to examine the effect of Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA+-M2BP) level on survival comparing with other laboratory liver fibrosis markers in hepatitis C virus (HCV)-related compensated liver cirrhosis (LC) (n = 165). For assessing prognostic performance of continuous fibrosis markers, we adapted time-dependent receiver operating characteristics (ROC) curves for clinical outcome. In time-dependent ROC analysis, annual area under the ROCs (AUROCs) were plotted. We also calculated the total sum of AUROCs in all time-points (TAAT score) in each fibrosis marker. WFA+-M2BP value ranged from 0.66 cutoff index (COI) to 19.95 COI (median value, 5.29 COI). Using ROC analysis for survival, the optimal cutoff point for WFA+-M2BP was 6.15 COI (AUROC = 0.79348, sensitivity = 80.0%, specificity = 74.78%). The cumulative five-year survival rate in patients with WFA+-M2BP ≥ 6.15 COI (n = 69) was 43.99%, while that in patients with WFA+-M2BP < 6.15 COI (n = 96) was 88.40% (p < 0.0001). In the multivariate analysis, absence of hepatocellular carcinoma (p = 0.0008), WFA+-M2BP < 6.15 COI (p = 0.0132), achievement of sustained virological response (p < 0.0001) and des-γ-carboxy prothrombin < 41 mAU/mL (p = 0.0018) were significant favorable predictors linked to survival. In time-dependent ROC analysis in all cases, WFA+-M2BP had the highest TAAT score among liver fibrosis markers. In conclusion, WFA+-M2BP can be a useful predictor in HCV-related compensated LC. 相似文献
843.
Yoshinori Saito Kenichi Shimizu Takeshi Nobukawa Atsuhshi Satsuma 《Topics in Catalysis》2010,53(7-10):584-590
Effects of Pt and Ba content of Pt/Ba/Al2O3 on NO x storage reduction (NSR) catalyst were investigated by means of kinetic analysis of surface nitrates using in situ FT/IR. Turnover frequencies of both storage and reduction of nitrate were significantly enhanced at higher Ba content, while those were higher at lower Pt content below 0.2 wt%. 相似文献
844.
Yoshinori Miura 《Polymer Bulletin》2014,71(6):1441-1448
Methylcellulose (MC), a hydrophobically modified cellulose derivative, in an aqueous solution undergoes sol-to-gel and gel-to-sol transitions on heating and cooling, respectively. Using differential scanning calorimetry, MC in light (H2O) and heavy (D2O) water solutions has been investigated to elucidate the solvent isotope effect on the transitions. As a result, their transition temperatures are higher in H2O by about 4 °C than D2O. This phenomenon is rationalized in terms of the strength of the hydrophobic attractive interaction; the strength is enhanced by D2O. We discuss the reason for the enhancement and the difference in the isotope effect between MC and a poly(N-isopropylacrylamide) polymer which shows an opposite trend to MC. 相似文献
845.
Wenting Wu Gaku Ichihara Naozumi Hashimoto Yoshinori Hasegawa Yasuhiko Hayashi Saeko Tada-Oikawa Yuka Suzuki Jie Chang Masashi Kato Corina N. D’Alessandro-Gabazza Esteban C. Gabazza Sahoko Ichihara 《International journal of molecular sciences》2015,16(1):660-676
Zinc oxide (ZnO) nanoparticles are widely used in various products, and the safety evaluation of this manufactured material is important. The present study investigated the inflammatory and fibrotic effects of pulmonary exposure to ZnO nanoparticles in a mouse model of pulmonary fibrosis. Pulmonary fibrosis was induced by constant subcutaneous infusion of bleomycin (BLM). Female C57BL/6Jcl mice were divided into BLM-treated and non-treated groups. In each treatment group, 0, 10, 20 or 30 µg of ZnO nanoparticles were delivered into the lungs through pharyngeal aspiration. Bronchoalveolar lavage fluid (BALF) and the lungs were sampled at Day 10 or 14 after administration. Pulmonary exposure by a single bolus of ZnO nanoparticles resulted in severe, but transient inflammatory infiltration and thickening of the alveolar septa in the lungs, along with the increase of total and differential cell counts in BLAF. The BALF level of interleukin (IL)-1β and transforming growth factor (TGF)-β was increased at Day 10 and 14, respectively. At Day 10, the synergistic effect of BLM and ZnO exposure was detected on IL-1β and monocyte chemotactic protein (MCP)-1 in BALF. The present study demonstrated the synergistic effect of pulmonary exposure to ZnO nanoparticles and subcutaneous infusion of BLM on the secretion of pro-fibrotic cytokines in the lungs. 相似文献
846.
Ko Ikeda Kyoichi Onikura Yoshinori Nakamura Swaroop Vedanand 《Journal of the American Ceramic Society》2001,84(8):1717-1720
A nickel-bearing silicate gel was prepared from sodium disilicate and nickel nitrate solutions at room temperature. Then, the gel was heat-treated in air up to 800°C at intervals of 200°C. The products were completely amorphous after heating at ≤600°C. However, liebenbergite and cristobalite were identified as products of the crystallization of the gel after heating at 800°C. The polycondensation process of the gel was discussed based on X-ray diffractometry, thermogravimetry-differential thermal analysis, and optical spectroscopy, to clarify the easy crystallization of the gel to liebenbergite and cristobalite. The present technique is very useful for the low-temperature preparation of liebenbergite, which has potential application in the decomposition catalysis of chlorofluorocarbons, in connection with the problem with the ozone layer. 相似文献
847.
Masamichi Koseki Sumiko Fujiki Yoshinori Tanaka Hiroyuki Noguchi Toshikazu Nishikawa 《Journal of food science》2005,70(4):S249-S253
ABSTRACT: The effect of water hardness on the taste of alkaline electrolyzed water (AEW) was examined by sensory evaluation. Sensory test 1 of commercial bottled mineral water to which calcium and/or magnesium salts had been added was performed by panelists who evaluated the effect of hardness on the taste of water using a scoring method (hedonic scaling test) and a 1-pair comparison method. The water, in which the calcium concentration and the magnesium concentration was 20 mg/L and 2 mg/L, respectively, was found to taste better than any water containing other concentrations of calcium and magnesium. Sensory test 2 of bottled mineral waters having hardnesses of 30 mg/L to 290 mg/L, of activated carbon filtration water having a hardness of 50 mg/L, and of AEWs was performed by panelists using a scoring method (hedonic scaling test) and a pair test, and their preferences for the taste of AEWs was surveyed. The taste of AEW made by electrolyzing activated carbon filtration water did not differ from that of the water before it was electrolyzed. The same was true of AEW made by electrolyzing bottled mineral water having a hardness of 80 mg/L. However, 3 kinds of AEWs made by electrolyzing bottled mineral waters having hardnesses of 30 mg/L, 170 mg/L, and 290 mg/L were found to taste less pleasant than each bottled mineral water before being electrolyzed. The results of sensory tests 1 and 2 show that good-tasting AEW could be produced by an alkaline water electrolyzed from most tap water of Japan because its hardness varies from approximately 50 mg/L to 80 mg/L. 相似文献
848.
Naruki Endo Hiroyuki SaitohAkihiko Machida Yoshinori Katayama 《International Journal of Hydrogen Energy》2013
We investigated the hydrogenation of a binary TiFe alloy at 5 GPa and 600 °C by in situ synchrotron radiation X-ray diffraction measurements. After formation of a solid solution of hydrogen in TiFe, an order–disorder phase transition in the metal lattice of TiFe occurred, which yielded a BCC TiFe hydride. The unit cell volume of the BCC hydride increased by 21.0% after the hydrogenation reaction. The volume expansion was larger than that of a γ-hydride TiFeH1.9 prepared by hydrogenation near ambient conditions. 相似文献
849.
Fujita T Guan P McKenna K Lang X Hirata A Zhang L Tokunaga T Arai S Yamamoto Y Tanaka N Ishikawa Y Asao N Yamamoto Y Erlebacher J Chen M 《Nature materials》2012,11(9):775-780
Distinct from inert bulk gold, nanoparticulate gold has been found to possess remarkable catalytic activity towards oxidation reactions. The catalytic performance of nanoparticulate gold strongly depends on size and support, and catalytic activity usually cannot be observed at characteristic sizes larger than 5 nm. Interestingly, significant catalytic activity can be retained in dealloyed nanoporous gold (NPG) even when its feature lengths are larger than 30 nm. Here we report atomic insights of the NPG catalysis, characterized by spherical-aberration-corrected transmission electron microscopy (TEM) and environmental TEM. A high density of atomic steps and kinks is observed on the curved surfaces of NPG, comparable to 3-5 nm nanoparticles, which are stabilized by hyperboloid-like gold ligaments. In situ TEM observations provide compelling evidence that the surface defects are active sites for the catalytic oxidation of CO and residual Ag stabilizes the atomic steps by suppressing {111} faceting kinetics. 相似文献
850.
Yuji Shimada Yoshinori Hirota Takashi Baba Akio Sugihara Shigeru Moriyama Yoshio Tominaga Tadamasa Terai 《Journal of the American Oil Chemists' Society》1999,76(6):713-716
Steryl esters of long-chain fatty acids have water-holding properties, and polyunsaturated fatty acids (PUFA) have various physiological functions. Because steryl ester of PUFA can be expected to have both features, we attempted to synthesize steryl esters of PUFA by enzymatic methods. Among lipases used, Pseudomonas lipase was the most effective for the synthesis of cholesteryl docosahexaenoate. When a mixture of cholesterol/docosahexaenoic acid (3:1, mol/mol), 30% water, and 3000 units/g of lipase was stirred at 40°C for 24 h, the esterification extent attained 89.5%. Under the same reaction conditions, cholesterol, cholestanol, and sitosterol were also esterified efficiently with docosahexaenoic, eicosapentaenoic, arachidonic, and γ-linolenic acids. 相似文献