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91.
Intira KoodkaewShigeru Matsuyama Yukari SunoharaHiroshi Matsumoto 《Tetrahedron letters》2012,53(8):977-979
Hapalocyclamide, a novel oxazole-, thiazole- and thiazoline-containing cyclic hexapeptide, was isolated from the terrestrial cyanobacterium Hapalosiphon sp., and which showed phytotoxic activity on lettuce seedling growth. The gross structure of hapalocyclamide was established from spectroscopic data and chemical degradation. The absolute stereochemistry was determined by Marfey’s analysis. Hapalocyclamide was established as cyclo-thiazole-l-alanine-oxazole-d-alanine-d-thiazoline-d-phenylalanine. 相似文献
92.
Yuki Yamaguchi Yukari Emoto Tohru Kineri Masakatsu Fujimoto Hideo Mae Atsuo Yasumori Keishi Nishio 《Ionics》2012,18(5):449-453
A well-known gasochromic material is Pt particle-dispersed tungsten trioxide (Pt/WO3). Its optical properties could make it effective as a hydrogen gas sensor. In this study, Pt nanoparticle-dispersed WO3 thin films were prepared using the sol–gel process, and their optical and electrical properties dependent on the working
environment (i.e., temperature, hydrogen gas concentration, oxygen partial pressure, etc.) were investigated. The Pt/WO3 thin films prepared at 400 °C showed the largest change in optical transmittance and electrical conductivity when exposed
to hydrogen gas compared with the films prepared at other temperatures. The optical absorbance and electrical conductivity
were found to be dependent on the hydrogen and oxygen gas concentration in the atmosphere because generation and disappearance
of W5+ in the thin films depend on the equilibrium reaction between injection and rejection of H+ into and from the thin films. In addition, the equilibrium reaction depends on the hydrogen and oxygen gas concentrations. 相似文献
93.
Yukari Imai Shingo Hirono Haruka Matsuba Dr. Tomohiro Suzuki Dr. Yuka Kobayashi Prof. Dr. Hirokazu Kawagishi Dr. Daisuke Takahashi Prof. Dr. Kazunobu Toshima 《化学:亚洲杂志》2012,7(1):97-104
Anthraquinone–lectin hybrids were effectively synthesized using water‐soluble anthraquinone derivative 11 with concanavalin A (ConA) and hygrophorus russula lectin (HRL) to give anthraquinone–ConA ( 16 ) and anthraquinone–HRL ( 17 ) hybrids, respectively. These anthraquinone–lectin hybrids effectively and selectively degraded oligosaccharides containing a mannose residue as a non‐reducing terminal sugar, which has affinity for ConA and HRL, under photo‐irradiation with long‐wavelength UV light without additives and under neutral conditions. In addition, anthraquinone–HRL ( 17 ) selectively photo‐degraded only Man(α1,6)Man, which has a high affinity for HRL, among several mannosides by recognition of both the type and glycosidic linkage profile of the sugar in an oligosaccharide. 相似文献
94.
95.
Yukari Kishimoto 《Journal of luminescence》2009,129(9):1055-1059
Blue light-emitting glasses were successfully prepared by doping Eu2+ ions in the system Al2O3-SiO2. The Al2O3-SiO2 glasses doped with Eu3+ ions were synthesized using a sol-gel method, followed by heating in hydrogen gas atmosphere to reduce into the Eu2+ ions. The obtained glasses exhibited emission spectra with peak at ∼450 nm due to 4f65d→4f7 (8S7/2) transition, the intensities of which strongly changed depending on their glass composition and heating conditions. The emission quantum efficiency of 48% was achieved by heating the glass with the ratio of Al3+ to Eu3+ at about 6 at 1000 °C in hydrogen gas atmosphere. It was found that the Al2O3-SiO2 glasses were appropriate not only for homogeneously doping the Eu3+ ions in glass structure but also reducing to Eu2+ ions, resulting in enhanced blue light-emission properties. 相似文献
96.
Mutsuo Tanaka Takahiro Sawaguchi Yukari Sato Kyoko Yoshioka Osamu Niwa 《Tetrahedron letters》2009,50(28):4092-718
A series of phosphorylcholine-oligoethylene glycol-alkane thiols were synthesized, and their suppressive effect on the non-specific adsorption of proteins was evaluated by comparison with corresponding oligoethylene glycol-alkane thiols. It was found that phosphorylcholine-oligoethylene glycol-alkane thiols had a greater suppressive effect on the non-specific adsorption of proteins. 相似文献
97.
Cho T Kohagura J Numakura T Hirata M Higaki H Hojo H Ichimura M Ishii K Islam KM Itakura A Katanuma I Minami R Nakashima Y Saito T Tatematsu Y Watanabe O Yoshikawa M Kojima A Miyake Y Miyata Y Shimizu K Tomii Y Yoshida M Sakamoto K Imai T Pastukhov VP Miyoshi S;GAMMA Group 《Physical review letters》2006,97(5):055001
Off-axis electron-cyclotron heating in an axisymmetric barrier mirror produces a cylindrical layer with energetic electrons, which flow through the central cell and into the end region. The layer, producing a localized bumped ambipolar potential Phi(C), forms a strong shear of radial electric fields E(r) and peaked vorticity with the direction reversal of E(r)xB sheared flow near the Phi(C) peak. Intermittent vortexlike turbulent structures near the layer are suppressed in the central cell by this actively produced transverse energy-transport barrier; this results in T(e) and T(i) rises surrounded by the layer. 相似文献
98.
Wataru NAKANO Satomi KOBAYASHI Takayuki MAEZAWA Yukari OHASHI Yutaka KOHNO 《Physical Therapy Research》2021,24(3):280
OBJECTIVE: Adequate physical activity after stroke is critical for cardiovascular health. Although sex is a potential factor associated with post-stroke physical activity, its mechanism remains unclear. This study aimed to examine sex differences in human physical activity following stroke. METHOD: A cross-sectional study with 62 participants (men: 42, women: 20) was conducted. Physical activity was measured for three consecutive days using a step activity monitor. The walking durations per day in light physical activity, moderate-to-vigorous physical activity, and total physical activity were calculated. Sex differences in walking duration were compared using Welch''s t-tests or Mann-Whitney U tests. RESULTS: Women had a significantly greater walking duration in light physical activity and in total than did the men. In contrast, no significant differences were found in moderate-to-vigorous physical activity. CONCLUSION: This study reported sex differences in the walking duration after stroke. Moreover, it found that women spent more time in low intensity physical activity than men. Our results will be useful for planning interventions to increase physical activity and decrease sedentary behavior after stroke. 相似文献
99.
X. X. Hu T. Sakiyama K. Itakura 《Archive of Applied Mechanics (Ingenieur Archiv)》2002,72(4-5):330-341
Summary A numerical procedure is proposed for the analysis of free vibrations of pretwisted thin plates. An accurate strain–displacement
relationship based on the thin-shell theory combined with the finite element method using triangular plate elements with three
nodes and nine degrees of freedom for each node is utilized. The vibration characteristics of pretwisted thin plates with
different twist rates and aspect ratios are studied. The numerical results are compared with the previous results obtained
by various types of finite elements and by the Rayleigh–Ritz method. The effect of the twist rate on the vibration characteristics
is studied briefly.
Received 28 February 2001; accepted for publication 18 December 2001 相似文献
100.
Facilitated transport of oxygen in a solid Polymer membrane containing cobaltporphyrin (CoP) which carries oxygen specifically and reversibly, leads to permselectivity of oxygen against nitrogen in the membrane. The increase in concentration of the CoP carrier is expected to enhance the oxygen transport. The membranes of poly(octylmethacrylate-co-vinylimidazole) containing 0.8 ~ 10 wt% CoP were prepared, and the effects of the CoP-concentration on the transport and the diffusion constants of oxygen are studied. Although the induction period before the steady state of oxygen permeation was prolonged with the CoP concentration in the polymer membrane, the glass transition temperature (Tg) of the membrane was increased and the diffusion constants of oxygen were decreased with the CoP concentration to yield unexpected reduction of the oxygen permeation in the highly CoP loaded membrane. 相似文献