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521.
Makoto Asai Yasushi Yamaki Satoshi Takahashi Yasuhiro Koike 《Journal of Polymer Science.Polymer Physics》2011,49(20):1464-1469
Radial refractive index profiles within the graded index plastic optical fiber (GI‐POF) is formed by adding a dopant to a polymer. This addition of the dopant significantly decreased the Tg of the polymer due to the plasticization. This disadvantage made the installation of the GI‐POF difficult, especially in vehicle networks in which high thermal stability is required. We have suggested 9‐bromophenanthrene (BPT) as a novel dopant induced less plasticization for poly(methyl methacrylate) (PMMA) than the conventional dopants. However, although the fabricated GI‐POF using BPT had high enough thermal stability for vehicle networks, the attenuation was 800 dB/km and it could not be used. This high attenuation was caused by contaminant in the fabrication process of fibers. In this study, we succeeded to fabricate a GI‐POF with low‐attenuation and high‐thermal stability using highly pure BPT. Its attenuation was improved to 240 dB/km at 650 nm, which was enough transparency for vehicle networks. The Tg of the GIPOF was improved to 107 °C from 90 °C. The thermal stability of the GI‐POF below 85 °C/dry and 75 °C/85%RH was demonstrated to be as high as that of the commercially available step index POF. The bandwidth of the GI‐POF could be estimated over 4.0 GHz for the 50‐m fiber. These results demonstrated that our GI‐POF should qualify to be used in vehicle network. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1464–1469, 2011 相似文献
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525.
Yang Gou Bingyang Liu Mengyao Cheng Takako Yamada Tetsuo Iida Sixian Wang Ryoichi Banno Teruhiko Koike 《Molecules (Basel, Switzerland)》2021,26(20)
Background: d-Allulose is a rare sugar with antiobesity and antidiabetic activities. However, its direct effect on insulin sensitivity and the underlying mechanism involved are unknown. Objective: This study aimed to investigate the effect of d-allulose on high-fat diet (HFD)-induced insulin resistance using the hyperinsulinemic–euglycemic (HE)-clamp method and intramuscular signaling analysis. Methods: Wistar rats were randomly divided into three dietary groups: chow diet, HFD with 5% cellulose (HFC), and HFD with 5% d-allulose (HFA). After four weeks of feeding, the insulin tolerance test (ITT), intraperitoneal glucose tolerance test (IPGTT), and HE-clamp study were performed. The levels of plasma leptin, adiponectin, and tumor necrosis factor (TNF)-α were measured using the enzyme-linked immunosorbent assay. We analyzed the levels of cell signaling pathway components in the skeletal muscle using Western blotting. Results: d-allulose alleviated the increase in HFD-induced body weight and visceral fat and reduced the area under the curve as per ITT and IPGTT. d-Allulose increased the glucose infusion rate in the two-step HE-clamp test. Consistently, the insulin-induced phosphorylation of serine 307 in the insulin receptor substrate-1 and Akt and expression of glucose transporter 4 (Glut-4) in the muscle were higher in the HFA group than HFC group. Furthermore, d-allulose decreased plasma TNF-α concentration and insulin-induced phosphorylation of stress-activated protein kinase/Jun N-terminal kinase in the muscle and inhibited adiponectin secretion in HFD-fed rats. Conclusions: d-allulose improved HFD-induced insulin resistance in Wistar rats. The reduction of the proinflammatory cytokine production, amelioration of adiponectin secretion, and increase in insulin signaling and Glut-4 expression in the muscle contributed to this effect. 相似文献
526.
We present a leading order (LO) estimate for the longitidinal-transverse spin asymmetry (A
) in the nucleon-nucleon polarized Drell-Yan process at RHIC and
energies in comparison with A
and A
. A
receives contribution from g1, the transversity distribution h1, and the twist-3 distributions g
and h
. For the twist-3 contribution we use the bag model prediction evolved to a high energy scale by the large-Nc evolution equation. We found that A
(normalized by the asymmetry in the parton level) is much smaller than the corresponding A
. Twist-3 contribution given by the bag model turned out to be negligible. 相似文献
527.
C. Petrascu S. Bianco A.M. Bragadireanu F.L. Fabbri C. Guaraldo M. Iliescu T.M. Ito V. Lucherini M. Bregant E. Milotti A. Vacchi E. Zavattini M. Augsburger D. Chatellard P. Knowles F. Mulhauser L.A. Schaller L. Schellenberg H. Schneuwly J.-P. Egger D. Varidel W.H. Breunlich M. Cargnelli B. Gartner R. King B. Lauss J. Marton J. Zmeskal T. Ponta S.N. Nakamura T. Koike R.S. Hayano M. Hori T. Ishikawa T. Ishiwatari M. Iwasaki Y. Akaishi G. Beer A.C. Sanderson R. Seki 《Hyperfine Interactions》1999,118(1-4):53-57
The DEAR (DAΦNE Exotic Atom Research) experiment at the new φ-factory DAΦNE of Laboratori Nazionali di Frascati aims for a
1% measurement of the line shift of the K-complex due to strong interaction in kaonic hydrogen. This presentation is meant to prove that the high statistics and good
resolution obtainable with DEAR will be able to disentangle the kaonic hydrogen K-complex lines (a cascade unconstrained fit), obtaining in this way constraints for what concerns the cascade parameters and,
consequently, information regarding the physical processes involved in the kaonic hydrogen atomic cascade.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
528.
New triterpenoid saponins from Maesa tenera. 总被引:2,自引:0,他引:2
Two new triterpenoid saponins, maetenosides A and B were isolated from the aerial parts of Maesa tenera and were respectively defined as 3-O-[beta-D-glucopyranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->3)][beta-D-glucopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl camelliagenin A 22-O-angelate (1) and 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->3)][beta-o-glucopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl camelliagenin A 22-O-angelate (2). Their structures were established on the basis of chemical and spectroscopic methods. 相似文献
529.
Tsukamoto S. Namihira T. Douyan Wang Katsuki S. Hackam R. Akiyama H. Sato A. Uchida Y. Koike M. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2001,29(1):29-36
NOx removal methods using plasma chemical reactions in nonthermal plasmas have been widely studied. In this paper, the effects of the addition of fly ash on NOx removal using short-pulsed discharge plasmas are described. Fly ash which had been collected from a coal-burning thermal electrical power plant was used. Experiments were performed using four different mixtures of gases which included NO. These were (N2+NO), (N2+NO+O2), (N2+NO+H2O), and (N2+NO+O2+H 2O). These gas mixtures were used either with or without the addition of fly ash. The initial concentration of NO was fixed at 200 ppm (NO parts per million of the gas mixture), The study of the NOx (NO+NO2) removal was performed with the fly ash, as it is relevant to real situations in coal power plants. The results show that the presence of fly ash decreased the NOx removal rate slightly in the case of dry gas mixtures while it increased the NOx removal rate substantially in the case of wet gas mixtures. These results suggest that the presence of fly ash in the flue gases, which also contain a few percentages of moisture, would be advantageous to the treatment of flue gases emitted from thermal power plants for the removal of nitrogen oxides 相似文献
530.
H. Shimizu K. Imai N. Tamura K. Nisimura K. Hatanaka T. Saito Y. Koike Y. Taniguchi 《Nuclear Physics A》1982,382(2):242-254
Analyzing powers and differential cross sections for elastic scattering have been measured at 64.8 MeV. The angular distributions cover center-of-mass angles between 8° and 169°. The relative uncertainties of the analyzing power measurement are typically ± 0.005 at c.m. angles less than 80° and are in general ± 0.015 at the remaining angles. The absolute scale of the analyzing power measurement has an uncertainty of ± 0.013. The data are compared with three-body calculations based on the Faddeev theory. In contrast with the differential cross sections, the analyzing powers could not be reproduced without the D-wave nucleon-nucleon interactions. 相似文献