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131.
Minoru Toriumi Ryohei Katooka Kazuko Yui Toshitaka Funazukuri Chang Yi Kong Seiichiro Kagei 《Fluid Phase Equilibria》2010
Infinite dilution binary diffusion coefficients, D12, of ferrocene, 1,1′-dimethylferrocene and ethylferrocene in hexane, cyclohexane and ethanol at 313.2 K and pressures from 0.2 to 19 MPa, in acetonitrile at 298.2–333.2 K and 0.2 MPa, and various metallic acetylacetonate, acac, complexes such as Co(acac)3, Ru(acac)3, Rh(acac)3, Pd(acac)2 and Pt(acac)2 mainly in ethanol at 313.2 K and 0.2 MPa were measured by the Taylor dispersion method. The D12 values in m2 s−1 for the three ferrocenes in the present study and those of ferrocene and 1,1′-dimethylferrocene in supercritical carbon dioxide in our previous studies were represented by the modified hydrodynamic equation over a wide range of viscosity: M0.5D12/T = 1.435 × 10−13η−0.8446 with average absolute relative deviation of 2.40% for 316 data points, where M is the solute molecular weight, T is the temperature in K, η is the solvent viscosity in Pa s. Although the D12 values for the acac complexes were roughly represented by the above hydrodynamic equation, the accuracies were lower because they were dependent on not solute molecular weight but the number of acac ligand in the complex molecules. 相似文献
132.
Takeaki Iwamoto Takashi Abe Kunihisa Sugimoto Daisuke Hashizume Hiroshi Matsui Ryohei Kishi Masayoshi Nakano Shintaro Ishida 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(13):4415-4419
Bicyclo[1.1.0]tetrasil‐1(3)‐ene 1 , a tetrasilicon analogue of bicyclo[1.1.0]but‐1(3)‐ene that contains a formal double bond between bridgehead silicon atoms in an inverted geometry, was synthesized and isolated in the form of thermally stable orange crystals. The distance between the bridgehead Si atoms in 1 is much longer than those in typical Si=Si bonds, but still shorter than that of a previously reported pentasila[1.1.1]propellane. DFT calculations suggest that the bridgehead bond in 1 comprises a σ bond with an inverted geometry and a π bond. This notion is supported by the UV/Vis spectrum of 1 , which exhibits several absorption bands in the UV/Vis region. While 1 is stable toward typical trapping agents for Si=Si double bonds, 1 reacts with carbon tetrachloride to furnish a hexachlorotetrasilane. 相似文献
133.
Ryohei Nakata Katsuyasu Kawano Minoru Sumita Eiichi Higuchi 《Journal of Physics and Chemistry of Solids》1979,40(12):955-959
Oxidation and reduction processes of europium ions in CaF2 were studied by optical and ESR methods. Europium ions can be readily oxidized from the divalent to the trivalent states by heat-treatment above 600°C in a moist air atmosphere. The conversion can be well approximated by first order kinetics with an activation energy of 0.75 eV.
The reverse conversion from the trivalent to the divalent states can be accomplished by exposure to ionizing X-ray radiation. However, those reduced europium ions are thermally unstable and bleached completely by heating to 200°C. The decay process by low temperature annealing also follows first order kinetics with an activation energy of 0.60 eV. The conversions between the two states are explained by electron transfer. 相似文献
134.
135.
A new effective catalytic system consisting of [CpRhCl(2)](2)/K(2)CO(3) (Cp = pentamethylcyclopentadienyl) for the lactamization of amino alcohols has been developed. As an example, the reaction of 3-(2-aminophenyl)-1-propanol in the presence of [CpRhCl(2)](2) (5.0% Rh) and K(2)CO(3) (10%) in acetone gives 3,4-dihydro-2(1H)-quinolinone in an isolated yield of 80%. A variety of five-, six-, and seven-membered benzo-fused lactams are synthesized by this catalytic system. [reaction: see text] 相似文献
136.
137.
Minoru Sumita Katsuyasu Kawano Ryohei Nakata 《Journal of Physics and Chemistry of Solids》1978,39(5):557-561
ESR studies of europium ions in alkali chlorides and bromides were performed at room and liquid nitrogen temperatures. There were first reported spin Hamiltonian parameters for NaBr: Eu2+ and RbBr: Eu2+ crystals and also for coagulated europium ions in NaCl, KCl, KBr and RbBr crystals. The dependence of b20 and b22 on the lattice constant, a, of host crystals was discussed; a single relation b20αa?2.6 was obtained, while relations for b22 were treated seperately for Na, K and Rb halide series, respectively. From the relative values of b22 and b20, displacements of the nearest neighbor anions surrounding the Eu2+-vacancy pair were estimated to be 0.083a for NaCl and NaBr, 0.081a for KC1, 0.080a for KBr, 0.074a for RbCl and 0.078a for RbBr. 相似文献
138.
Ryohei Makino 《Mathematische Zeitschrift》1985,189(4):571-592
139.
Masaaki Kubota Yoshimasa Fujishiro Ryohei Ishida 《Spectrochimica Acta Part B: Atomic Spectroscopy》1982,37(10):849-857
A 1024-element silicon photodiode array with a microchannel plate image intensifier was coupled to a Czerny-Turner spectrometer and basic characteristics of the spectrometer system were studied using an Hg lamp, a hollow cathode lamp and a d.c. argon plasma as emission sources. The intensifier proved to be useful to enhance signals without increasing the electronic background. The signal to dark current ratio of the cooled photodiode array was larger than that of a photomultiplier (HTV R457) in the wavelength region above 380 nm. Effects of entrance slit width, integration time per scan and intensifier gain on signal to background ratios and signal to noise ratio are presented and optimum conditions for emission measurements using the system are described. 相似文献
140.
Ryohei Nakata Katsuyasu Kawano Minoru Sumita Elichi Hlguchi 《Journal of Physics and Chemistry of Solids》1980,41(10):1119-1126
The characteristics of allowed and forbidden transitions of Eu2+ ions in CaF2 single crystals have been investigated at room temperature. The Angular dependences of these transition intensities were theoretically calculated with the use of perturbation theory, and compared with the experimental values. The experimental results can be explained by taking into account crystal field effects , and a hyper fine interaction AiS · Ii in the spin Hamiltonian. 相似文献