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121.
122.
Satoru Nakashima Yuichi Masuda Izumi Motoyama Hirotoshi Sano 《Hyperfine Interactions》1988,40(1-4):319-322
It was found that the packing of cations and anions influences the electronic structures of mixed-valence binuclear ferrocene derivatives. Temperature-dependence of the mixed-valence state of 11, 1111-diisobutylbiferrocenium triiodide was observed in a crystalline state, whereas only a trapped-valence state was found in a dispersed state. The packing effect was also observed for a series of 11, 1111-dialkyl- and 11, 1111-bis(methylbenzyl)biferrocenium triiodides by means of ESR spectroscopy. 相似文献
123.
124.
Ion irradiation effects on improvement of flux-pinning properties for quenched and melt growth YBCO samples (QMG-materials)
were studied. Irradiation with 16MeV protons was performed up to a dose of 1×1016 p/cm2. The effective activation energies of vortices are expressed with the formula, Ueff=g(T)h(H)f(J) ∝ (J/Jc)−∝* [1-(T/Tx)2]2/3*H−1/3 at lower irradiation doses below 5×1015 p/cm2. The J-dependence of Ueff changes from power-law to quesi-exponential dependence with an increment of irradiation dose. 相似文献
125.
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127.
Optical channel waveguides of meta-nitroaniline (m-NA) crystal, which has potential applications to nonlinear optical devices, have been fabricated on glass substrates having fine grooves. The crystal growth was performed by zone-melting, scanning a CO2 laser beam along the grooves filled with the polycrystal m-NA. Optical and X-ray observations showed that zone-melting changed the polycrystalline state to a single crystalline state with the 〈001〉 direction along the groove. The scattering loss for a 5 mm-long m-NA crystal waveguide (100 μm both in width and in depth) was found to decrease from 50 dB to 2.5 dB with this process. 相似文献
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129.
The aldol reaction of formaldehyde with the dicyclopentylborinyl enolate derived from -(or -) 1-tert-butyldimethylsilyloxy-l-cyclohexylbutan-2-one, followed by desilylation and sodium meta-periodate oxidation, provides -(or -) β-hydroxyisobutyric acid. 相似文献
130.
Watano S Okamoto T Sato Y Ohnishi Y Yasutomo T Osako Y 《Chemical & pharmaceutical bulletin》2005,53(1):18-21
A novel multi-functional vertical high shear kneader has been developed and its performance in wet kneading has previously been reported [Watano et al., Chem. Pharm. Bull., 50(3), 341-345 (2002)]. In this study, scale-up of wet kneading in the novel vertical high shear kneader was conducted. Pharmaceutical excipients composed of lactose, cornstarch and micro-crystalline cellulose were used as powder samples. Kneading operations were conducted under various operating conditions and three different vessel scales. The dried pellets were then prepared by extruding the wet kneaded masses through a dome-type extruder and their drying by a fluidized bed. The physical properties such as strength and disintegration time of the dried pellets were evaluated. It was found that the properties of the dried pellets and their scale-up characteristics were well expressed by an agitation power per unit vessel volume and dimensionless Froude number. 相似文献