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561.
562.
Keishin Mizoguchi Yoshinori Kamiya Takuji Hirose 《Journal of Polymer Science.Polymer Physics》1991,29(6):695-703
Gas permeation measurements were performed by the time-lag method for 13 gases in poly [bis(trifluoroethoxy) phosphazene] above the mesophase transition, T (1) transition, of the crystals. Hysteresis was found in the temperature dependence of the permeability coefficients for CO2, O2, and N2 in the transition region as observed by dilatometry and differential scanning calorimetry. Independently the solubility of CO2 was determined gravimetrically above and below T(1). Noticeable change and hysteresis were also observed in the temperature dependence of the solubility coefficients. Diffusion of CO2 in the measophase is suggested from the permeation and sorption measurements. Gas transport parameters of CO2 in the mesophase are estimated, and the contributions of the mesophase and the crystalline phase to gas transport are considered. 相似文献
563.
564.
Zn?Fe intermediate phases have been investigated. The distribution of quadrupole splittings P(QS) was determined from the Mössbauer spectrum: the P(QS) gives evidence for two different iron sites in the γ phase. The analysis of Mössbauer spectrum taken in an applied magnetic field shows the negative sign of electrical field gradients is present. 相似文献
565.
566.
Kazuyuki Kasuga Takuji Hirose Seiichi Aiba Toshikazu Takahashi Kazuhisa Hiratani 《Tetrahedron letters》1998,39(52):4111-9702
Lipophilic alkaline earth metal complexes, prepared from the corresponding metal hydroxides and phosphoric acid diesters, are quite effective for the transport of some monosaccharides, especially ribose, across a chloroform liquid membrane under neutral conditions. 相似文献
567.
The transient optogalvanic spectrum of Ne 585.2, 588.2, and 603.0 nm lines was observed using a chopped CW dye laser in the negative glow region of a hollow cathode lamp. The analysis revealed that the signal originates mainly from the vicinity of the cathode surface and that the hitherto utilized model of the effect has to be generalized to include the colisional mixing among nearby levels into the rate equations for the population distribution among atomic levels. 相似文献
568.
569.
In the selection of an appropriate material which satisifes the impact strength requirement for an injection moduled product, the Charpy, Izod or dart drop test methods should be used according to the impact mode displayed by the product—that is, either snap impact on a bar or impact on a shell structure—because generally the ranking of a material determined by the Charpy test differs from that determined by the dart drop test. However, preference for the Charpy test, because of the advantage of simples evaluation work, sometimes leads to erroneous judgement of product characteristics. The breaking behaviour of various materials as determined by Charpy apparatus equipped with instrumentation was studied, and a new design of Charpy test was shown to correlate with the dart drop impact test. The procedure used was to provide a bigger notch tip radius, to break the specimen parallel to the flow direction in the injection moulding process, and to apply the energy absorbed until the beginning of fracture at the notch end. 相似文献
570.
We demonstrate efficient degenerate four-wave mixing in a laser injection-seeded solid dye laser. Phase-conjugate energy of as much as 140 times the total energy injected externally into the phase conjugator was extracted. Moreover, efficient phase-conjugate energy was obtained in the broad wavelength region from 558 to 567 nm. 相似文献