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131.
Okada Y Matsuda K Hara K Hamayasu K Hashimoto H Koizumi K 《Chemical & pharmaceutical bulletin》1999,47(11):1564-1568
The novel heterogeneous branched cyclodextrins (CDs), 6-O-alpha-D- galactosyl-alpha, -beta, and -gamma CDs (Gal-alpha, -beta, and -gamma CDs) and 6-O-alpha-D-mannosyl-alpha, -beta, and -gamma CDs (Man-alpha, -beta, and -gamma CDs) dissolved sufficiently in water and in 10-50% (v/v) methanol aqueous solutions, as did the homogeneous branched CDs, 6-O-alpha-D-glucosyl-alpha, -beta, and -gamma CDs (Glc-alpha, -beta, and -gamma CDs). The solubilities of heterogeneous branched CDs were higher than those of each parent non-branched CDs. The hemolytic activities of heterogeneous and homogeneous branched CDs were lower than those of each parent non-branched CDs and the hemolytic activity became weaker in the order of non-branched CD > Man-CD > Glc-CD > Gal-CD in each series of alpha, beta, and gamma CD. AL type solubility-phase diagrams were displayed in the formation of inclusion complexes of the guest compounds of small size (methyl benzoate, estriol, and dexamethasone) with Gal-, Man-, and Glc-CDs, and marked differences among the three kinds of branched CDs could not be detected. However, solubility-phase diagrams between these branched CDs and the insoluble guest compounds of large cyclic structure (cyclosporin A, tacrolimus, and amphotericin B) showed AP type, and the improvement of water solubilities of these guest compounds with three kinds of branched CDs was enhanced in the order of Man-CDs > Glc-CDs > Gal-CDs. 相似文献
132.
133.
T Koizumi M Kakemi K Katayama H Inada K Sudeji M Kawasaki 《Chemical & pharmaceutical bulletin》1990,38(4):1019-1021
High frequency pulse iontophoresis of diclofenac sodium across excised guinea-pig skin was carried out in vitro. An equivalent circuit model was constructed to simulate the time courses of voltage drop across the donor solution and the skin. Parameter values obtained by the least-squares adaptation of the model to observed data were consistent with expectation and validated the proposed model. 相似文献
134.
Uni-sized platinum clusters (size range of 5-40) on a silicon(111)-7 x 7 surface were prepared by depositing size-selected platinum cluster ions on the silicon surface at the collision energy of 1.5 eV per atom at room temperature. The surface thus prepared was observed by means of a scanning tunneling microscope (STM) at the temperature of 77 K under an ambient pressure less than 5 x 10(-9) Pa. The STM images observed at different cluster sizes revealed that (1) the clusters are flattened and stuck to the surface with a chemical-bond akin to platinum silicide, (2) every platinum atom occupies preferentially the most reactive sites distributed within a diameter of approximately 2 nm on the silicon surface at a cluster size up to 20, and above this size, the diameter of the cluster increases with the size, and (3) the sticking probability of an incoming cluster ion on the surface increases with the cluster size and reaches nearly unity at a size larger than 20. 相似文献
135.
Y. Toh M. Koizumi M. Oshima A. Kimura Y. Hatsukawa A. Osa J. Goto 《Journal of Radioanalytical and Nuclear Chemistry》2007,272(2):303-305
In order to improve the sensitivity for the quantification of trace elements, we propose the combination of prompt gamma-ray
analysis (PGA) and a multiple gamma-ray detection method. A new Ge detector system for multiple prompt gamma-ray analysis
(MPGA) was constructed at the neutron guide-hall of the JRR-3M reactor of the Japan Atomic Energy Agency (JAEA). The first
demonstration of this system was given with a plastic sample containing traces of cadmium. The quantification limit of cadmium
in a plastic sample was found to be about 0.1 ppm. 相似文献
136.
Kenzo Kitayama Hiroyuki Ohno Masaru Kurahashi Eiko Koizumi Manabu Inagaki 《Journal of solid state chemistry》2003,174(2):249-256
Phase equilibrium was established in the Yb-Mn-O and Dy-Mn-O systems at 1100°C by varying the oxygen partial pressure from −log (PO2/atm)=0-13.00, allowing construction of phase diagrams at 1100°C for the systems Ln2O3-MnO-MnO2. Under experimental conditions, Yb2O3, MnO, Mn3O4, and YbMnO3 phases are found to be present in the Yb-Mn-O system, whereas Dy2O3, MnO, Mn3O4 DyMnO3, and DyMn2O5 phases are present in the Dy-Mn-O system. Ln2MnO4, Mn2O3, and MnO2 are not stable in either system. Small nonstoichiometric ranges are found in the LnMnO3 phase, with the nonstoichiometry represented by the equations, NO/NYbMnO3=1.00×10−4(log PO2)3+1.30×10−3(log PO2)2+7.20×10−3(log PO2)+5.00×10−5 and NO/NDyMnO3=1.00×10−4(log PO2)3+1.80×10−3(log PO2)2+9.30×10−3(log PO2)+1.69×10−2. Activities of the components in the solid solutions are calculated using these equations. LnMnO3 may range Ln2O3-rich to Ln2O3-poor, while MnO is slightly nonstoichiometric to the oxygen-rich side. DyMn2O5 also seems to be nonstoichiometric. Lattice constants of LnMnO3 under different oxygen partial pressures were determined, as well as lattice constants of DyMn2O5 quenched in air. The standard Gibbs energy changes of reactions appearing in the phase diagrams were calculated. 相似文献
137.
138.
139.
Ebara Y. Koizumi T. Sone H. Nemoto Y. 《Components and Packaging Technologies, IEEE Transactions on》2000,23(2):293-299
The authors have observed the relationship between waveform of electromagnetic noise and change of surface for opening Ag-Pd electric contacts. In case of Ag-Pd electrodes, continuous noise is observed in the whole period of arc discharge in both current polarities. Fluctuations of are voltage and noise are large in the middle part of arc discharge duration. The noise decreases in the later half. The authors proposed a classification of noise waveforms and pattern of surface changes. As a result, patterns of noise waveform and changes of electrode surface at various circuit conditions are classified into three categories. In this paper, the authors showed the correlation between pattern of noise waveform and the change of electrode surface 相似文献
140.