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941.
Yasunori Matsui Minoru Shigemori Toshiyuki Endo Takuya Ogaki Eisuke Ohta Kazuhiko Mizuno Hiroyoshi Naito Hiroshi Ikeda 《Research on Chemical Intermediates》2018,44(8):4765-4774
The semiconductor properties of the earliest known stable radical, α,γ-bisdiphenylene-β-phenylallyl radical (Koelsch radical, 1?) were assessed using spectroscopic and electrical techniques. This radical undergoes reversible redox processes, and it has low redox potentials. In addition, 1? possesses long wavelength absorption bands, owing to the existence of a singly-occupied molecular orbital whose energy level lies between those of the HOMO and LUMO. A spin-coated thin-film of 1? displays photocurrent and an electron mobility of 6.3 × 10?7 cm2 V?1 s?1 on a trially-fabricated organic field effect transistor. 相似文献
942.
Kim DT Kwan Y Lee JJ Ikeda T Uchida T Kamjoo K Kim YH Ong JJ Athill CA Wu TJ Czer L Karagueuzian HS Chen PS 《Chaos (Woodbury, N.Y.)》1998,8(1):137-148
In support of the spiral wave theory of reentry, simulation studies and animal models have been utilized to show various patterns of spiral wave tip motion such as meandering and drifting. However, the demonstration of these or any other patterns in cardiac tissues have been limited. Whether such patterns of spiral tip motion are commonly observed in fibrillating cardiac tissues is unknown, and whether such patterns form the basis of ventricular tachycardia or fibrillation remain debatable. Using a computerized dynamic activation display, 108 episodes of atrial and ventricular tachycardia and fibrillation in isolated and intact canine cardiac tissues, as well as in vitro swine and myopathic human cardiac tissues, were analyzed for patterns of nonstationary, spiral wave tip motion. Among them, 46 episodes were from normal animal myocardium without pharmacological perturbations, 50 samples were from normal animal myocardium, either treated with drugs or had chemical ablation of the subendocardium, and 12 samples were from diseased human hearts. Among the total episodes, 11 of them had obvious nonstationary spiral tip motion with a life span of >2 cycles and with consecutive reentrant paths distinct from each other. Four patterns were observed: (1) meandering with an inward petal flower in 2; (2) meandering with outward petals in 5; (3) irregularly concentric in 3 (core moving about a common center); and (4) drift in 1 (linear core movement). The life span of a single nonstationary spiral wave lasted no more than 7 complete cycles with a mean of 4.6+/-4.3, and a median of 4.5 cycles in our samples. Conclusion: (1) Patently evident nonstationary spiral waves with long life spans were uncommon in our sample of mostly normal cardiac tissues, thus making a single meandering spiral wave an unlikely major mechanism of fibrillation in normal ventricular myocardium. (2) A tendency toward four patterns of nonstationary spiral tip motion was observed. (c) 1998 American Institute of Physics. 相似文献
943.
944.
945.
Abbott T Akiba Y Beavis D Bloomer MA Bond PD Chasman C Chen Z Chu YY Cole BA Costales JB Crawford HJ Cumming JB Debbe R Engelage J Fung SY Gushue S Hamagaki H Hansen O Hayano RS Hayashi S Homma S Huang HZ Ikeda Y Juricic I Kang J Katcoff S Kaufman S Kimura K Kitamura K Kurita K Ledoux RJ Levine MJ Miake Y Morse RJ Moskowitz B Nagamiya S Olness J Parsons CG Remsberg LP Sakurai H Sarabura M Stankus P Steadman SG Stephans GS Sugitate T Tannenbaum MJ van Dijk JH Videbaek F Vient M Vincent P 《Physical review D: Particles and fields》1992,45(11):3906-3920
946.
947.
Fluorescent high-performance liquid chromatography of folic acid and its derivatives using permanganate as a fluorogenic reagent 总被引:1,自引:0,他引:1
Norio Ichinose Toshihiro Tsuneyoshi Mikako Kato Tokinori Suzuki Shigero Ikeda 《Fresenius' Journal of Analytical Chemistry》1993,346(6-9):841-846
Summary A fluorescent high-performance liquid chromatography (HPLC) analysis of folic acid (pteroylglutamic acid) and its derivatives using permanganate as a fluorogenic reagent has been developed. In the present work, the various analytical conditions in which the fluorogenic reaction with permanganate could be applied to the HPLC of folic acid in human serum, have been studied. The present method may be employed for the rapid clinical analysis of small amounts of folic acid (150 ppb), without interference from coexisting natural fluorophors; the precision of the present method for folic acid was 6.6% (n=6) (coefficient of variation).Dedicated to Professor Dr. Wilhelm Fresenius on the occasion of his 80th birthdayA part of this paper was presented at the 12th International Symposium on Microchemical Techniques, Cordoba (Spain), September 1992 相似文献
948.
949.
Takahara YK Ikeda S Ishino S Tachi K Ikeue K Sakata T Hasegawa T Mori H Matsumura M Ohtani B 《Journal of the American Chemical Society》2005,127(17):6271-6275
Spherical silica particles that are able to assemble at a phase boundary of a dual-phase mixture of water and an immiscible organic solvent were prepared by a partial modification of their surface hydroxyl groups with an alkylsilylation agent. Scanning electron microscopic observation of these particles in which their remaining surface hydroxyl groups had been selectively modified with colloidal gold particles revealed that each particle has an asymmetric surface structure: one side of the surface is hydrophilic and the other is hydrophobic. We found that these particles could form a micellar structure in water in the presence of an organic solution of a toluene/polystyrene mixture. The micellar structure was evidenced by formation of golf-ball-like polystyrene particles with dimples imprinting morphologies of the hydrophobic part of modified silica particles. 相似文献
950.
Takaishi S Tobu Y Kitagawa H Goto A Shimizu T Okubo T Mitani T Ikeda R 《Journal of the American Chemical Society》2004,126(6):1614-1615
81Br Nuclear quadrupole resonance (NQR) measurement was performed in an S = 1/2 one-dimensional Heisenberg antiferromagnetic metal complex [NiBr(chxn)2]Br2 (chxn: 1R,2R-diaminocyclohexane), having a halogen-bridged MX chain structure -Br-Ni3+-Br-Ni3+-Br-. Two 81Br NQR signals were observed below 40 K, while a single signal was observed above 130 K, showing the presence of two nonequivalent bridging Br sites below 40 K. This NQR result together with previously reported magnetic susceptibility and X-ray results indicate the occurrence of a transition into a spin-Peierls state between 40 and 130 K. This communication reports the first spin-Peierls transition in metal complexes in which pure d electrons contribute to the magnetism. In addition, we demonstrated a new experimental method for studying a spin-Peierls system. 相似文献