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91.
Angelo Sassaroli Fabrizio Martelli Yukari Tanikawa Kenji Tanaka Ryuichiro Araki Yoichi Onodera Yukio Yamada 《Optical Review》2000,7(5):420-425
The in vivo optical properties of a piglet brain were measured using a time-resolved system at three different wavelengths (759, 794, 824 nm). To separate the contribution of different head layers to the detected signals, the measurements were acquired from the surfaces of skin, skull, dura mater and brain. The source detector distance was chosen to assure a mean penetration depth within each layer. Measurements were analyzed and compared with the results of other in vivo measurements reported in literature. 相似文献
92.
Shingo Sato Hironobu Kumagai Shigeru Matsuba Toshihiro Kumazawa Jun-Ichi Onodera Masanobu Suzuki 《Journal of heterocyclic chemistry》1999,36(5):1345-1347
A flavanone, in which a hydroxyl group at the 5-position was protected with a methyl group, converted to the corresponding 5-methoxy-2-phenyl-4-quinolone via flavylium salt under mild conditions. Flavanone-O-rhamnoglucoside, naringin, was also converted to 5-methoxy-2-phenyl-4-quinolon-7-O-rhamnoglucoside in the same way in an overall 25% yield. 相似文献
93.
Ryuichi Wada Tomoki Nakayama Tetsuya Hiyama Yasushi Fujiyoshi Naoyuki Kurita 《Isotopes in environmental and health studies》2017,53(6):646-659
Isotope ratios of carbon dioxide and water vapour in the near-surface air were continuously measured for one month in an urban area of the city of Nagoya in central Japan in September 2010 using laser spectroscopic techniques. During the passages of a typhoon and a stationary front in the observation period, remarkable changes in the isotope ratios of CO2 and water vapour were observed. The isotope ratios of both CO2 and water vapour decreased during the typhoon passage. The decreases can be attributed to the air coming from an industrial area and the rainout effects of the typhoon, respectively. During the passage of the stationary front, δ13C–CO2 and δ18O–CO2 increased, while δ2H–H2Ov and δ18O–H2Ov decreased. These changes can be attributed to the air coming from rural areas and the air surrounding the observational site changing from a subtropical air mass to a subpolar air mass during the passage of the stationary front. A clear relationship was observed between the isotopic CO2 and water vapour and the meteorological phenomena. Therefore, isotopic information of CO2 and H2Ov could be used as a tracer of meteorological information. 相似文献
94.
Tasuku Onodera Yusuke Morita Michihisa Koyama Nozomu Hatakeyama Hiromitsu Takaba Momoji Kubo Jean-Michel Martin 《Applied Surface Science》2009,256(4):976-979
We investigated the influence of a nanometer scale film structure of a tribofilm generated from zinc dialkyldithiophosphate (ZDDP) anti-wear additive on its mechanical properties using a combined molecular dynamics (MD) and finite element (FE) method. The frictional behavior of an interface between a native iron oxide layer on steel surface and zinc metaphosphate - regarded as a model material of ZDDP tribofilm - was firstly studied using the MD method. The results showed that the iron atoms in the oxide layer diffused into the phosphate layer during the friction process. The zinc atoms in the phosphate layer also diffused into the oxide layer. Significant interdiffusion of iron and zinc atoms was observed with increasing simulation time. Thus, metallic phosphate with a gradient composition of iron and zinc atoms was formed on the phosphate/oxide interface. We then constructed an axisymmetric nanoindentation simulation model from the MD-derived structures at a certain simulation time and carried out a FE calculation. As a result, we found that the rubbed ZDDP tribofilm, including the phosphate with the gradient composition of metallic atoms, showed larger contact stiffness and hardness. The combined MD/FE simulation indicates that the tribofilm becomes stiffer and harder due to the interdiffusion of iron and zinc atoms on the tribofilm/oxide interface. We have found that the gradient composition formation in ZDDP tribofilm during friction process influences on its mechanical properties. 相似文献
95.
We discuss the scenario with TeV-scale right-handed neutrinos, which are accessible at future colliders, while holding down tiny seesaw-induced masses and sizable couplings to the standard-model particles. The signal with tri-lepton final states and large missing transverse energy is appropriate for studying collider signatures of the scenario with extra spatial dimensions. We show that the LHC experiment generally has a potential to discover the signs of extra dimensions and the origin of small neutrino masses. 相似文献
96.
Utana Umezaki Miu Hatakenaka Kana Onodera Hiroto Mizutani Suhyang Kim Yusuke Nakasone Masahide Terazima Yoshifumi Kimura 《Molecules (Basel, Switzerland)》2021,26(15)
The mechanism by which proteins are solvated in hydrated ionic liquids remains an open question. Herein, the photoexcitation dynamics of photoactive yellow protein dissolved in hydrated choline dihydrogen phosphate (Hy[ch][dhp]) were studied by transient absorption and transient grating spectroscopy. The photocyclic reaction of the protein in Hy[ch][dhp] was similar to that observed in the buffer solution, as confirmed by transient absorption spectroscopy. However, the structural change of the protein during the photocycle in Hy[ch][dhp] was found to be different from that observed in the buffer solution. The known change in the diffusion coefficient of the protein was apparently suppressed in high concentrations of [ch][dhp], plausibly due to stabilization of the secondary structure. 相似文献
97.
Arc-disjoint in-trees in directed graphs 总被引:2,自引:0,他引:2
Given a directed graph D = (V,A) with a set of d specified vertices S = {s
1,…, s
d
} ⊆ V and a function f: S → ℕ where ℕ denotes the set of natural numbers, we present a necessary and sufficient condition such that there exist Σ
i=1
d
f(s
i
) arc-disjoint in-trees denoted by T
i,1,T
i,2,…, for every i = 1,…,d such that T
i,1,…, are rooted at s
i
and each T
i,j
spans the vertices from which s
i
is reachable. This generalizes the result of Edmonds [2], i.e., the necessary and sufficient condition that for a directed
graph D=(V,A) with a specified vertex s∈V, there are k arc-disjoint in-trees rooted at s each of which spans V. Furthermore, we extend another characterization of packing in-trees of Edmonds [1] to the one in our case.
Supported by JSPS Research Fellowships for Young Scientists.
Supported by the project New Horizons in Computing, Grand-in-Aid for Scientific Research on Priority Areas, MEXT Japan. 相似文献
98.
Naoyuki Hoshiya 《Tetrahedron》2006,62(24):5808-5820
Five bicyclic dioxetanes bearing a 2-hydroxynaphthyl group, 1aA-1eA, were synthesized and their chemiluminescent decomposition was examined by the use of tetrabutylammonium fluoride (TBAF) as a base in DMSO. It was found that these dioxetanes hold completely the ‘odd/even’ relationship between the substitution pattern of hydroxy as a trigger on the naphthalene ring and their chemiluminescent efficiency, and that dioxetane 1aA exhibited chemiluminescence with the highest efficiency among those for the oxynaphthyl-substituted dioxetanes hitherto known. The significant change in chemiluminescent efficiency depending on the substitution pattern was clarified to be attributed to the marked change in singlet-chemiexcitation efficiency for charge-transfer-induced chemiluminescence (CTICL) of 1aA-1eA. In respect of the rate of CTICL-decomposition, ‘odd/even’ relationship was observed for 1aA-1dA. 相似文献
99.
Masakatsu Matsumoto Kazutaka Yamada Harumi Ishikawa Naoyuki Hoshiya Nobuko Watanabe Hisako K. Ijuin 《Tetrahedron letters》2006,47(47):8407-8411
Bicyclic dioxetanes 2a, 2b, and 3, bearing a 3-hydroxy-5-naphthylphenyl moiety underwent charge-transfer-induced decomposition with accompanying emission of light, the color of which changed from red to blue responding to a complex of crown ether with potassium t-butoxide used as a base. Furthermore, they afforded unusual chemiluminescence, the spectra of which displayed two peaks in some cases. It was observed for chemiluminescences in the coordination sphere with crown ether that their spectra did not coincide with the spectra of authentic emitters. 相似文献
100.
Morita Kentato Motoyama Keiichi Kuramoto Ayako Onodera Risako Higashi Taishi 《Journal of inclusion phenomena and macrocyclic chemistry》2021,100(3-4):169-175
Journal of Inclusion Phenomena and Macrocyclic Chemistry - In recent years, functional materials using cyclodextrin (CD)-based polyrotaxanes have attracted considerable attention, and... 相似文献