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11.
Toshihide Baba Satoru Hikita Haruhisa Handa Yoshio Ono 《Research on Chemical Intermediates》1998,24(5):495-505
Europium supported on alumina (Eu/Al2O3) was prepared by impregnation from an ammoniacal solution of the metal. The catalytic activity of Eu/Al2O3 for the isomerization of 2,3-dimethylbut-1-ene to 2,3-dimethylbut-2-ene was examined. Eu/Al2O3 showed the highest catalytic activity for the isomerization when heated under a vacuum at 523 K, the yield of 2,3-dimethylbut-2-ene
in 20 min being 81.6% at 314 K. IR spectrum shows the presence of two kinds of Eu amides. The change of the IR spectra and
the catalytic activities with evacuation temperature suggest that only one of the two Eu amides is catalytically active for
this base-catalyzed isomerization. 相似文献
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14.
N Shibata T Minouchi Y Hayashi H Shibata T Ono H Shimakawa 《Chemical & pharmaceutical bulletin》1989,37(7):1877-1880
The effects of temperature, hematocrit (Hct), lipid level in plasma and cyclosporin A (CyA) level in whole blood on the concentration of CyA in plasma measured by high-performance liquid chromatography were studied in vitro. With rise in blood storage temperature before cells were removed, the concentration of CyA in plasma was increased in the temperature range between 10 degrees C and 37 degrees C, but was decreased between 4 degrees C and 10 degrees C. With rise in Hct, the concentration of CyA in plasma was decreased, and it was more markedly decreased at the blood storage temperature of 4 degrees C than at 37 degrees C. A lipid supplementation study showed that the concentration of CyA in plasma was increased with rise in plasma triglyceride level and in plasma cholesterol level at the storage temperature of 4 degrees C but not at 37 degrees C. Studies of the effect of CyA concentration in blood on the CyA distribution in blood demonstrated that the cellular/plasma concentration (C/P) ratio at low levels (less than 200 micrograms/ml) of plasma CyA ranged from 4 to 10 and was about 2 times higher than that at higher concentrations at 4 degrees C, but the ratio was relatively constant at 37 degrees C. The saturation capacity of the cellular fraction for CyA showed considerable individual variations, but there was no difference between the capacities at 4 degrees C and 37 degrees C. The separation of plasma after equilibration at 37 degrees C made it possible to avoid the variations in the distribution of CyA in whole blood associated with changes in Hct, lipid level in plasma and CyA level in whole blood, and to obtain a measurement reflecting the physiologically significant concentration of CyA in plasma. 相似文献
15.
M. Takagaki K. Ono S-I. Masunaga Y. Kinashi Y. Sakurai T. Kobayashi S-I. Miyatake N. Hashimoto 《Journal of Radioanalytical and Nuclear Chemistry》2001,247(2):389-392
Quantitative determination of ppb-order 10B was carried out in a small number of cultured tumor cells by particle tracks by the 10B(n,)7Li reactions using solid state nuclear track detector (SSNTD) for boron neutron capture therapy research. The detection limit of 10B concentration in tumor cells is less than 1·10-3 ppm under our experimental conditions which permits the quantitative determination of 10B in a small number of boronated tumor cells (105/ml = ca. 0.1 mg). Boron quantities in tumor cells determined were well compatible with the tumor cell killing effects of boron neutron capture therapy. 相似文献
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17.
Kenji Yokota Hideo Tomioka Teruyuki Ono Fumimasa Kuno 《Journal of polymer science. Part A, Polymer chemistry》1972,10(5):1335-1343
The sensitization effect of tertiary amines on the photopolymerization of methyl methacrylate was studied. N,N-Dimethylbenzylamine, triethylamine, and N,N-dimethylaniline increased the rate of polymerization in this order, but pyridine did not show any effect. A free-radical mechanism was confirmed by the tacticity of polymer, the retarding effect of hydroquinone, and the copolymer composition with styrene. On the basis of the detailed kinetics of the sensitized polymerization and the ultraviolet spectra of the reaction mixtures, a sensitization mechanism is proposed, in which the excited monomer and the amine form a complex and generate an initiating radical. 相似文献
18.
Rikuhei Tanikaga Yoshimasa MatsumotoMaki Sakaguchi Yohei KoyamaKentaro Ono 《Tetrahedron letters》2003,44(35):6781-6783
Lipase-mediated acetylations of trans- and cis-2-substituted cyclohexanols gave the corresponding (1R)-cyclohexyl acetates and (1S)-cyclohexanols in high yields and ee, but c-4-tert-butyl-c-2-ethenyl-r-1-cyclohexanol was unreactive owing to the steric interaction between the axial OH group and the axial H atoms at the 3- and 5-positions. In the cis-isomer the OH group occupies an equatorial position to bind to the lipase, and less bulky axial alkenyl and alkynyl groups might not so much prevent acetylations than an alkyl group. 相似文献
19.
S. Tamai J. Kamada T. Ono T. Kuroki K. Goto A. Yamaguchi 《Journal of polymer science. Part A, Polymer chemistry》2002,40(3):423-428
Polyimide containing an indan unit and alkyl moiety with a high molecular weight was prepared from 5,7‐diamino‐1,1,4,6‐tetramethylindan and 3,3′,4,4′‐benzophenone tetracarboxylic dianhydride. This polyimide was amorphous and soluble in common organic solvents, such as tetrahydrofuran, chloroform, and cyclopentanone. Thermogravimetry of the polyimide showed good thermal stability, indicating that a 10% weight loss of the polyimide was observed at 500 °C in nitrogen. The glass‐transition temperature of the polyimide was not observed by DSC measurement between room temperature and 400 °C at a heating rate of 10 °C/min (Apparatus: DSC3100 MAC Science Co., Ltd.). Transparency of the polyimide at 365 nm was 80%. The polyimide acted as a photosensitive resist of negative type by UV radiation. The resist had a sensitivity of 31 mJ/cm2 and a contrast of 2.3 when it was developed with cyclopentanone at room temperature. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 423–428, 2002 相似文献
20.
A. Ono 《Chromatographia》1980,13(12):752-754
Summary Xylenol isomers can be resolved on most polyols (sugars or sugar alcohols) and polyethers (polyethylene glycol or polypropylene glycol) with hydrogen-bonding interaction. They are separated on vinical polyols which have more hydroxy hydrogen than tetrol, and even on vicinal triol when its hydroxy hydrogen is acidic (stronger proton donor). The stronger is the hydrogen bonding interaction between xylenols and the liquid phase, the better is the separation of 2,4- and 2,5-xylenol, and the poorer the separation of 2,4-and 2,3-xylenol. 相似文献