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991.
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994.
Naohiko Mikami Atsunari Hiraya Ichiro Fujiwara Mitsuo Ito 《Chemical physics letters》1980,74(3):531-535
The fluorescence excitation spectrum of the first singlet transition of aniline in a supersonic free jet has been measured. Vibronic transitions involving the inversion vibration of the NH2 group in the excited state have been observed. The double minimum potential function in the excited state has been determined from the observed vibrational levels. 相似文献
995.
T.G. Appleton M.A. Bennett A. Singh T. Yoshida 《Journal of organometallic chemistry》1978,154(3):369-385
The reactions of various alkyne-platinum(0) complexes with methyl iodide and with iodine have been studied. The 3-hexyne complex Pt(C2H5C2C2H5)(PPh3)2 gives alkyne-free oxidative addition products PtI(CH3) (PPh3)2 and PtI2 (PPh3)2 exclusively. In contrast, the strained cyclic alkyne complexes Pt(C6H8)(PPh3)2, Pt(C7H10)(PPh3)2, Pt(C6H8) (dppe) and Pt(C7H10) (dppe)1 react with methyl iodide to give mainly 2-methylcycloalkenyiplatinum(II) complexes, e.g. PtI(C6H8CH3) (PPh3)2, formed by electrophilic attack on the metal-alkyne bond. Iodine reacts similarly with Pt(C6H8) (PPh3)2 and Pt(C7H10) (PPh3)2 to give 2-iodocycloalkenylplatinum(II) complexes but, in the case of the corresponding dppe complexes, PtI2(dppe) is the main product. The insertion reaction of methyl iodide with Pt(C6H8)(PPh3)2 proceeds via an oxidative addition intermediate PtI(CH3) (C6H8) (PPh3)2 which can be isolated. Trifluoromethyl iodide reacts with Pt(C6H8)(PPh3)2 to give a 2-iodocyclohexenyl complex Pt(CF3) (C6H8I) (PPh3)2 and with Pt(C7H10) (PPh3)2 to give PtI(CF3) (PPh3)2. 31P NMR data are given and discussed. 相似文献
996.
T. Kitagawa M. Abe Y. Kyogoku H. Ogoshi H. Sugimoto Z. Yoshida 《Chemical physics letters》1977,48(1):55-58
Resonance Raman spectra of 15N enriched metallooctaethylporphyrins [M(OEP) ? 15N4] [M = Ni2+, Fe3+ (high spin), and Fe3+ (low spin)] were observed. Polarized Raman lines corresponding to the oxidation state marker band of hemoproteins were observed at 1377 (Ni), 1369 (Fe high spin) and 1372?1 (Fe low spin) which were shifted to lower frequency from those of the 14N compounds by 6, 5, and 6 cm?1, respectively. The vibrational mode for this band was shown to include an appreciable contribution of the CαN symmetric stretching vibration and to be associated with ca. 0.01 Å of in-phase displacement of the four pyrrole nitrogens toward the metal ion. 相似文献
997.
Jinhua Chen Yasunari Maekawa Masaru Yoshida Norio Tsubokawa 《Journal of Polymer Science.Polymer Physics》2002,40(1):134-141
A series of thermoresponsive polymer gel electrolytes (PGEs) based on poly(N‐isopropylacrylamide) in aqueous potassium chloride was synthesized by radiation‐induced polymerization and gelation using γ rays from a 60Co source. The electric conductivity and swelling properties of the PGE were determined as a function of temperature. It was found that the electric conductivity of the PGE depended strongly on the swelling ratio; most notably, it changed drastically near the volume phase‐transition temperature of the PGE. The temperature/conductivity profile of the PGE exhibits a maximum peak at a certain temperature that is defined as the maximum conductivity temperature (Tmax). The Tmax of all of the PGEs prepared by low‐dose irradiation agreed with the temperature, near the end of the volume phase transition, where the PGE was completely shrunken. Consequently, the conductivity of gels should provide a good method with which the totally shrunken temperature of the thermoresponsive gels can be monitored with good temperature precision. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 40: 134–141, 2002 相似文献
998.
Matsunaga S Yoshida T Morimoto H Kumagai N Shibasaki M 《Journal of the American Chemical Society》2004,126(28):8777-8785
Full details of a direct catalytic asymmetric Mannich-type reaction of a hydroxyketone using a Et2Zn/(S,S)-linked-BINOL complex are described. By choosing the proper protective groups on imine nitrogen, either anti- or syn-beta-amino alcohol was obtained in good diastereomeric ratio, yield, and excellent enantiomeric excess using the same zinc catalysis. N-Diphenylphosphinoyl (Dpp) imine 3 gave anti-beta-amino alcohols in anti/syn = up to >98/2, up to >99% yield, and up to >99.5% ee, while Boc-imine 4 gave syn-beta-amino alcohols in anti/syn = up to 5/95, up to >99% yield, and up to >99.5% ee. The high catalyst turnover number (TON) is also noteworthy. Catalyst loading was successfully reduced to 0.02 mol % (TON = up to 4920) for the anti-selective reaction and 0.05 mol % (TON = up to 1760) for the syn-selective reaction. The Et2Zn/(S,S)-linked-BINOL complex exhibited far better TON than in previous reports of catalytic asymmetric Mannich-type reactions. Mechanistic studies to clarify the reason for the high catalyst efficiency as well as transformations of Mannich adducts are also described. 相似文献
999.
Yoshikazu Suzuki Supachai Ngamsinlapasathian Ryuhei Yoshida Susumu Yoshikawa 《Central European Journal of Chemistry》2006,4(3):476-488
Partially nanowire-structured TiO2 was prepared by a hydrothermal processing followed by calcination in air. The hydrogen titanate powder as-synthesized was
calcined at 300 °C for 4 h to obtain the partially nanowire-structured TiO2. A dye-sensitized solar cell (DSC) with a film thickness of 5.6 μm, fabricated using the partially nanowire-structured TiO2 showed better performance than using a fully nanowire-structured TiO2 or a conventional equi-axed TiO2 nanopowder. The short-circuit current density (JSC), the open-circuit voltage (VOC), the fill factor (FF) and the overall efficiency (η) are 11.9 mA/cm2, 0.754 V, 0.673 and 6.01 %, respectively. The effects of one-dimensional nanostructure and electron expressway concept are
discussed. 相似文献
1000.
Konarev DV Khasanov SS Saito G Lyubovskaya RN Yoshida Y Otsuka A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(16):3837-3848
A method for the synthesis of the multicomponent ionic complexes: [Cr(I)(C(6)H(6))(2) (.+)][Co(II)(tpp)(fullerene)(-)].C(6)H(4)Cl(2), comprising bis(benzene)chromium (Cr(C(6)H(6))(2)), cobalt(II) tetraphenylporphyrin (Co(II)(tpp)), fullerenes (C(60), C(60)(CN)(2), and C(70)), and o-dichlorobenzene (C(6)H(4)Cl(2)) has been developed. The monoanionic state of the fullerenes has been proved by optical absorption spectra in the UV/vis/NIR and IR ranges. The crystal structures of the ionic [[Cr(I)(C(6)H(6))(2)](.+)](1.7)[[Co(II)(tpp)(C(60))](2)](1.7-). 3.3 C(6)H(4)Cl(2) and [[Cr(I)(C(6)H(6))(2)] (.+)](2)[Co(II)(tpp)[C(60)(CN)(2)]](-)[C(60)(CN)(2) (.-)]).3 C(6)H(4)Cl(2) are presented. The essentially shortened Co.C(fullerene) bond lengths of 2.28-2.32 A in these complexes indicate the formation of sigma-bonded [Co(II)(tpp)][fullerene](-) anions, which are diamagnetic. All the ionic complexes are semiconductors with room temperature conductivity of 2 x 10(-3)-4 x 10(-6) S cm(-1), and their magnetic susceptibilities show Curie-Weiss behavior. The neutral complexes of Co(II)(tpp) with C(60), C(60)(CN)(2), C(70), and Cr(0)(C(6)H(6))(2), as well as the crystal structures of [Co(II)(tpp)](C(60)).2.5 C(6)H(4)Cl(2), [Co(II)(tpp)](C(70)). 1.3 CHCl(3).0.2 C(6)H(6), and [Cr(0)(C(6)H(6))(2)][Co(II)(tpp)] are discussed. In contrast to the ionic complexes, the neutral ones have essentially longer Co.C(fullerene) bond lengths of 2.69-2.75 A. 相似文献