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11.
Toshihiko Hoshi Ken-ichi Kumagai Keita Inoue Shigendo Enomoto Yoko Nobe Michio Kobayashi 《Journal of luminescence》2008,128(8):1353-1358
Tris(8-quinolinolato)aluminum(III) (Alq3) shows electronic absorption bands at 378, 360 (in a 1:1 mixed solvent of methanol and ethanol (ME) at 77 K), 334, 316, 300, 263, 255.8, and 233 nm in ethanol at room temperature. According to the polarized fluorescence excitation spectrum together with MO calculations, for instance, the 360 nm band is assigned to an LL CT transition (an intramolecular charge transfer transition between two ligands), and the 378 nm band to an LM/ML CT one (an intramolecular charge transfer transition between ligand and metal). Alq3 shows a broad fluorescence band peaking at around 478 nm in the ME matrix at 77 K. The emission spectrum measured with a phosphoroscope has two emission bands at 567 and 478 nm. The 567 nm band accompanies vibronic bands at 578 and 605 nm, being safely assigned to a phosphorescence of Alq3. The lifetimes of the 478 and 567 nm bands are both 5.4 ms. The lifetime of the 478 nm band together with the band position and its band shape indicate that this band can be assigned to a delayed fluorescence. 相似文献
12.
Yoko Hirohara Yoshitaka OKawa Toshifumi Mihashi Tatsuo Yamaguchi Naoki Nakazawa Yasuko Tsuruga Hiroyuki Aoki Naoyuki Maeda Ichiro Uchida Takashi Fujikado 《Optical Review》2007,14(3):151-158
The purpose of this paper was to investigate the feasibility of a newly developed hyperspectral fundus imaging camera with
a liquid crystal tunable filter. The intensities of different wavelengths of light transmitted through an artery, vein, and
the area surrounding these vessels and reflected out were measured, and the differential spectral absorptions were analyzed.
Measurements were made from 16 normal eyes and from two artificial capillaries. The ratios of absorption (ROA) of arteries
to veins from 500 to 580 nm (range 1) and from 600 to 720 nm (range 2) were calculated. For all eyes, the ROArange1 was larger than ROArange2. The ROA obtained from the artificial capillary filled with blood saturated with oxygen or nitrogen was similar to that of
simulated data of oxy- and deoxyhemoglobin extinction rate. Most ROAs of human eyes were lower than those of the simulated
data and the artificial capillaries. Oxygen saturation analysis by hyperspectral fundus imaging of retinal vessels were qualitatively
in agreement with thein vitro analysis or simulated values. However, further improvements are necessary to evaluate the oxygen saturation quantitatively
in the retinal blood vessels. 相似文献
13.
14.
Hiroya Yamaguchi Yoshie Yotsukura Hirosaku Sata Yoko Watanabe Hajime Hirose Noriko Kobayashi Diane M. Bless 《Journal of voice》1993,7(3)
A voice therapy program using pushing exercises to correct glottal incompetence is described. The program utilizes various types of instrumentation to determine whether or not a given patient is likely to benefit from the treatment. The program also provides feedback of target voices. Three cases with incomplete glottal closure and subsequent vocal dysphonia characterized by an asthenic breathy quality are used to illustrate the program. Details of the program, termination criteria, and problems and precautions learned from treating 29 patients over a 3-year period are presented. 相似文献
15.
Sol-Gel Processing of Transparent PLZT((Pb,La)(Zr,Ti)O3) Fibers 总被引:1,自引:0,他引:1
Kitaoka Kenji Takahara Koji Kozuka Hiromitsu Yoko Toshinobu 《Journal of Sol-Gel Science and Technology》1999,16(1-2):183-193
PLZT((Pb,La)(Zr,Ti)O3) ceramic fibers were prepared by the sol-gel method from a solution of lead acetate trihydrate, lanthanum isopropoxide, zirconium n-propoxide and titanium isopropoxide containing 2-methoxyethanol as the solvent. The as-drawn gel fibers were pretreated in an autoclave and preheated in flowing H2O vapor prior to the heat-treatment for crystallization. The effects of autoclaving and preheating in flowing H2O vapor on the structure and composition of the resultant fibers were investigated. Optically transparent single phase perovskite PLZT fibers of 5–15 m in thickness and 5 cm in length were successfully prepared when the autoclave-treatment and the preheating in flowing H2O vapor were conducted prior to crystallization. These treatments are thought to promote hydrolysis of the organic groups and polycondensation reaction in the gel fibers, leading to the successful formation of dense, crack-free transparent PLZT fibers. 相似文献
16.
Dr. Yoko Hasegawa Dr. Thomas Cantin Dr. Jonathan Decaens Dr. Samuel Couve-Bonnaire Prof. Dr. André B. Charette Prof. Dr. Thomas Poisson Prof. Dr. Philippe Jubault 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(47):e202201438
The first diastereo- and enantioselective cyclopropanation reactions of electron-deficient allenes with donor-acceptor and diacceptor diazo reagents are described. The desired enantioenriched alkylidenecyclopropanes (ACPs) were obtained in high yields with high diastereo- and enantioselectivities in the presence of Rh2((S)-TCPTAD)4 or Rh2((R)-BTPCP)4 catalysts (up to 95 % yield, >95 : 5 d.r. and 99 : 1 e.r.). This methodology gave a direct access to ACPs bearing multiple electron-deficient substituents and allows to further expand the availability of ACPs chemistry. Interestingly, during the examination of the scope of this reaction, the asymmetric intramolecular C−H insertion reaction into tert-butyl group was observed as a side reaction with up to 94 : 6 e.r. 相似文献
17.
Yoko Nambu Takeshi Endo Makoto Okawara 《Journal of polymer science. Part A, Polymer chemistry》1985,23(1):223-230
A lipoamide (LAm) structure was introduced into a polymeric membrane by chemical modification of poly(γ-methyl-D -glutamate) (PMG). A. redox reaction proceeded across the membrane mediated by pendant LAm groups as solid carriers. It is suggested that the electron transport process in the membrane is derived from the exchange reaction between reduced LAm (thiol) and LAm (disulfide). 相似文献
18.
Kiyoshi Tanemura Yoko Nishida Tsuneo Suzuki Koko Satsumabayashi Takaaki Horaguchi 《Journal of heterocyclic chemistry》1997,34(2):457-460
1,3-Dithianes 1 , 1,3-dithiolanes 2 , and diphenyl dithioacetals 3 derived from cinnamaldehydes reacted with 2,3-dichloro-5,6-dicyano-p-benzoquinone in aqueous solvents to give benzaldehydes 4 . Hydride transfer from 1–3 to 2,3-dichloro-5,6-dicyano-p-benzoquinone followed by hydrolysis and oxidative carbon-carbon bond cleavage would produce benzaldehydes 4 . 相似文献
19.
20.
Ishikawa Y Matsumoto Y Nishida Y Taniguchi S Watanabe J 《Journal of the American Chemical Society》2003,125(21):6558-6562
Silicon carbide (SiC) and diamond were decomposed to CO(2)(g) by the photocatalysis with TiO(2) at room temperature, although the decomposition rate of diamond was very slow. According to the XPS spectra of Si2p on the SiC surface, SiO(2) was simultaneously formed on the surface by the TiO(2) photocatalysis. The thickness of the SiO(2) formed on the SiC surface during the photocatalytic oxidation for 1 h was estimated to be about 40 A from the depth profile of the XPS spectra using Ar etching. The SiC surface was oxidized by the TiO(2) photocatalysis even under the condition without a direct contact with the TiO(2). This indicates that the photocatalytic oxidation of the SiC occurs due to active oxygen species photogenerated on the TiO(2) surface, but not by hole produced in the valence band of the TiO(2). Moreover, a remote surface treatment system using the quartz beads coated with TiO(2) was developed for the SiC surface oxidation. Consequently, the TiO(2) photocatalysis will be very useful for the surface treatment of SiC such as photopatterning without defects and damage to the substrate because the photocatalytic reaction is carried out under mild conditions. 相似文献