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101.
Keiji Yamamoto Takuma Nakao Etsuo Yonemochi Toshio Oguchi 《Journal of inclusion phenomena and macrocyclic chemistry》1996,25(1-3):121-124
The inclusion process of naphthalene into heptakis-(2,6-di-O-methyl)--cyclodextrin (DMCD) during the sealed heating was investigated by using solid state time,resolved fluorescent analysis. Fluorescence lifetimes of naphthalene in naphthalene crystals and in inclusion complex with DMCD prepared by coprecipitation were determined 59 ns and 88 ns, respectively. Fluorescence lifetime of naphthalene monomer becomes longer after inclusion complex formation. Fluorescence lifetimes of naphthalene monomer and excimer in the sealed heating complex were determined about 80 ns and 100 ns, respectively. By setting the observing wavelength of time resolved fluorescent analysis at 355 nm, the formation and the decay of the excimer state of naphthalene during the sealed heating process were successfully confirmed. 相似文献
102.
The [MoCu] carbon monoxide dehydrogenase (CODH) is a Cu-containing molybdo-flavoprotein, the active site of which contains a pterin-dithiolene cofactor bound to a sulfido-bridged dinuclear Mo-Cu complex. In this paper, the synthesis and characterization of dinuclear Mo-Cu complexes relevant to the active site of [MoCu]-CODH are described. Reaction of [MoO2S2]2- with CuCN affords the dinuclear complex [O2MoS2Cu(CN)]2- (1), in which the CN- ligand can be replaced with various aryl thiolates to give rise to a series of dinuclear complexes [O2MoS2Cu(SAr)]2- (Ar = Ph (2), o-Tol (3), and p-Tol (4)). An alternative synthesis of complex 2 is the reaction of [MoO2S2]2- with [Cu(SPh)3]2-. Similarly, [O2MoS2Cu(PPh3)]- (5), [O2MoS2Cu(dppe)]- (dppe = 1,2-bis(diphenylphosphino)ethane) (6), and [O2MoS2Cu(triphos)]- (triphos = 1,1,1-tris[(diphenylphosphino)methyl]ethane) (7) were prepared from the reactions of [MoO2S2]2- with the Cu(I) phosphine complexes. Treatment of 1, 2, 4, or 5 with dithiols (1,2-(SH)2C6H4, 1,2-(SH)2C6H2-3,6-Cl2, and 1,2-(SH)2C2H4), in acetonitrile, leads to the replacement of a molybdenum-bound oxo ligand to yield [(dithiolate)Mo(O)S2CuL]2- (L = CN, SAr; dithiolate = 1,2-S2C6H4, 1,2-S2C6H2-3,6-Cl2, or 1,2-S2C2H4) (8-13) or [(1,2-S2C6H4)Mo(O)S2Cu(PPh3)]- (14) complexes. 相似文献
103.
Aggregation‐Induced Delayed Fluorescence Based on Donor/Acceptor‐Tethered Janus Carborane Triads: Unique Photophysical Properties of Nondoped OLEDs
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In Seob Park Jiyoung Lee Prof. Dr. Takuma Yasuda 《Angewandte Chemie (International ed. in English)》2016,55(25):7171-7175
Luminescent materials consisting of boron clusters, such as carboranes, have attracted immense interest in recent years. In this study, luminescent organic–inorganic conjugated systems based on o‐carboranes directly bonded to electron‐donating and electron‐accepting π‐conjugated units were elaborated as novel optoelectronic materials. These o‐carborane derivatives simultaneously possessed aggregation‐induced emission (AIE) and thermally activated delayed fluorescence (TADF) capabilities, and showed strong yellow‐to‐red emissions with high photoluminescence quantum efficiencies of up to 97 % in their aggregated states or in solid neat films. Organic light‐emitting diodes utilizing these o‐carborane derivatives as a nondoped emission layer exhibited maximum external electroluminescence quantum efficiencies as high as 11 %, originating from TADF. 相似文献
104.
RhI‐Catalyzed Intramolecular Carbonylative C−H/C−I Coupling of 2‐Iodobiphenyls Using Furfural as a Carbonyl Source
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Takuma Furusawa Prof. Dr. Tsumoru Morimoto Dr. Yasuhiro Nishiyama Dr. Hiroki Tanimoto Prof. Dr. Kiyomi Kakiuchi 《化学:亚洲杂志》2016,11(16):2312-2315
Synthesis of fluoren‐9‐ones by a Rh‐catalyzed intramolecular C?H/C?I carbonylative coupling of 2‐iodobiphenyls using furfural as a carbonyl source is presented. The findings indicate that the rate‐determining step is not a C?H bond cleavage but, rather, the oxidative addition of the C?I bond to a RhI center. 相似文献
105.
Han Z Fujioka T Usugi S Yorimitsu H Shinokubo H Oshima K 《Organic & biomolecular chemistry》2005,3(9):1622-1623
Treatment of alpha, beta-unsaturated carbonyl compounds or methyl propargyl ether with acylchlorobis(cyclopentadienyl)titanium in the presence of triethylamine and a copper salt in aqueous THF resulted in acylation of the carbon-carbon multiple bond, yielding the corresponding 1,4-diketones in good yields. 相似文献
106.
Hiroshi Sato Takuma Ishikawa Ryoichi Kikuchi 《Journal of Physics and Chemistry of Solids》1985,46(12):1361-1370
The meaning of cross terms in the Onsager equation for diffusion in multicomponent systems is clarified based on the Path Probability method of irreversible statistical mechanics. The problems involved in increasing the concentration of tracer atoms in tracer diffusion experiments are discussed. Some comments on the correlation function approach with respect to the present problem are also added. 相似文献
107.
A. Schenzle R. G. Devoe R. G. Brewer F. Shimizu K. Umezu H. Takuma S. K. Saha R. W. Hellwarth G. C. Bjorklund W. Zapka M. D. Levenson A. C. Tam W. Lenth F. M. Schellenberg T. F. Gallagher R. Kachru F. Gounand W. H. Weber R. W. Terhune A. le Floch J. M. Lenormand R. le Naour J. E. M. Goldsmith 《Applied physics. B, Lasers and optics》1982,28(2-3):297-305
108.
Modulating Photo‐ and Electroluminescence in a Stimuli‐Responsive π‐Conjugated Donor–Acceptor Molecular System
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Kohei Isayama Dr. Naoya Aizawa Dr. Jun Yun Kim Prof. Dr. Takuma Yasuda 《Angewandte Chemie (International ed. in English)》2018,57(37):11982-11986
Functional organic materials that display reversible changes in fluorescence in response to external stimuli are of immense interest owing to their potential applications in sensors, probes, and security links. While earlier studies mainly focused on changes in photoluminescence (PL) color in response to external stimuli, stimuli‐responsive electroluminescence (EL) has not yet been explored for color‐tunable emitters in organic light‐emitting diodes (OLEDs). Here a stimuli‐responsive fluorophoric molecular system is reported that is capable of switching its emission color between green and orange in the solid state upon grinding, heating, and exposure to chemical vapor. A mechanistic study combining X‐ray diffraction analysis and quantum chemical calculations reveals that the tunable green/orange emissions originate from the fluorophore's alternating excited‐state conformers formed in the crystalline and amorphous phases. By taking advantage of this stimuli‐responsive fluorescence behavior, two‐color emissive OLEDs were produced using the same fluorophore in different solid phases. 相似文献
109.
Generation of 16-fs, 10-TW pulses at a 10-Hz repetition rate with efficient Ti:sapphire amplifiers 总被引:1,自引:0,他引:1
We describe a two-stage Ti:sapphire amplifier laser system that is capable of producing 16-fs pulses of 10-TW peak power at a 10-Hz repetition rate. Thin solid etalons were used to control gain narrowing and gain saturation during amplification. A cylindrical mirror expander was used to permit compensation of the dispersion of the system. An efficiency greater than 90% of the theoretical maximum for conversion of 532-nm pump light to 790-nm radiation is demonstrated. 相似文献
110.
This paper examines the dynamic property of a macroeconomic model developed by Matsuyama [Am. Econ. Rev. 97(2007), pp. 503–516] in detail. It is shown that the model can be transformed into a version of the neuron model analysed by Hata [J. Math. Kyoto Univ. 22(1982), pp. 155–173, Chaos in Neural Network Models (in Japanese), Asakura, Tokyo 1998] and that the system can exhibit either periodic fluctuations or non-periodic (chaotic) fluctuations. 相似文献