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151.
Adsorption of CO on evaporated Ag and Cu films was studied by ellipsometry and resistivity measurements. Changes in ellipsometric angles δΔ and δψ due to adsorption of CO were analyzed by an improved linear approximation of the stratified layer model of adsorption. Adsorption of CO on Cu induced a 23% increase in the relative resistivity change (δR/R) which was proportional to δψ, while adsorption of CO on Ag induced a 1% increase without the proportionality. The dielectric constant of CO adsorbed on Ag is at λ = 1152 nm in comparison to ?1 = 2.1 for gas phase CO; that of CO on Cu is , which is consistent with the prediction by the Bennett and Penn theory. The large difference in ge1, of adsorbed CO on Ag and Cu is understood in terms of the energy level of the 2 π molecular orbital of adsorbed CO relative to the Fermi level. A possibility of adlayer plasmon excitation is discussed. 相似文献
152.
Toshio Motojima Shun-ichi Ikawa Masao Kimura 《Journal of Quantitative Spectroscopy & Radiative Transfer》1981,26(3):177-185
The i.r. absorption intensities have been measured of the fundamental vibrations of water molecules in metal halide aqueous solutions. Pseudo-isosbestic points were observed in the regions of both the stretching and bending vibrations and interpreted in terms of two states of water molecules in the solutions. The intensities of the stretching vibrations of water molecules coordinated to the dissolved ions have been estimated. The intensities become stronger in the order, Li+ > Na+ > K+ for the cations and F- > Cl- > Br- > I- for the anions. These orders are consistent with the strengths of the ion-water interactions, which are related to the dynamical behavior of the water molecules in the primary hydration shell. 相似文献
153.
Masao Doi 《Chemical physics》1975,11(1):115-121
A simplified version of the closure approximation, presented in the preceding paper, is applied to the reaction of rigid or flexible macromolecular systems. Two effects are found to be important for understanding the characteristic features of the reaction rates of these systems: (i) the orientation effect, which expresses the accessibility of the active sites, and (ii) the relaxation effect, which reflects the nature of the brownian motion of the active sites. 相似文献
154.
Shun-Ichi Ikawa Sachiko Takahasi Masao Kimura 《Journal of Quantitative Spectroscopy & Radiative Transfer》1975,15(12):1093-1099
The dielectric-field correction on i.r. band shape in the liquid has been studied by using the Lorentz internal field. The deformation of the band shape is inappreciable for a weak absorption band that becomes measurable only at a sample thickness larger than 10μ. The shapes of the strong singlet and doublet bands of hexafluorobenzene at 1530 cm?1 and near 1000 cm?1, respectively, and also of the doublet band of carbon tetrachloride near 790 cm?1 have been measured in dilute solutions and compared with those for the pure liquid. 相似文献
155.
The moment analyses were performed on the far-infrared absorption bands of CH3CN, CHCl3, CH2Cl2, and their deuterated compounds dissolved in nonpolar solvents. The values of torque acting on the solute molecules were estimated from the fourth moments. The band profiles were simulated by means of the continued-fraction representation of the time correlation function by Mori, using the moment values obtained. The third order long-time approximation of the correlation function yields essentially good simulations. The effective rotation angles of molecules between collisions were estimated from the first positive-to-negative turning points of the memory functions. The solvent effects on the torque and the rotation angle were consistent with each other. 相似文献
156.
Masao Doi 《Chemical physics letters》1974,26(2):269-272
The viscoelastic properties of concentrated polymer solutions are discussed on the basis of the fixed tube model proposed by de Gennes. It is shown that the steady flow viscosity is proportional to M3, where M is the molecular weight, and that the relaxation spectrum exhibits a hump in the relaxation time proportional to M3. 相似文献
157.
Seiji Yamaguchi Masao Mutoh Masaaki Shimakura Kunihiro Tsuzuki Yoshiyuki Kawase 《Journal of heterocyclic chemistry》1991,28(1):119-123
Some ω-(3-chromonyl)alkanoic acid derivatives, 1a and 2a , n = 4, 5; 3a, 4a and 5a , n = 2-6, were synthesized by cyclization of corresponding methyl ω-(2-hydroxybenzoyl)alkanoates 7b or ethyl ω-(2,4-dihydroxybenzoyl)alkanoates 8b with N,N-dimethylformamide-dimethyl acetal or acetic anhydride-DBU followed by hydrolysis. 相似文献
158.
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
159.
We derive a theorem of exponential decay of correlation functions at high temperature for a general statistical mechanical system following the approach introduced by L. Gross. The theorem is formulated so as to be useful for locality problems in lattice quantum gravity. 相似文献
160.
Masao Kimura Roger S. Porter Gideon Salee 《Journal of Polymer Science.Polymer Physics》1983,21(3):367-378
Blends of poly(butylene terephthalate) (PBT) and a copolyester of bisphenol-A with 50% terephthalate-50% isophthalate (PAr), before and after transesterification, have been studied by thermal and dynamic mechanical tests to determine crystallinity and phase behavior. Blends without transesterification, as prepared by solution precipitation, show a single Tg, indicating amorphous miscibility of PBT and PAr. A melting-point depression for PBT crystals is not observed; this means that PBT crystallizes excluding PAr and the entropy of melting is small. The highest fractional crystallinity for PBT is obtained at 20-35% of PAr. Transesterified blends were obtained by holding the physical blends at 250°C for up to 16 h. The transesterified systems show higher Tg's than the corresponding physical blends and also show a marked melting-point depression and lesser PBT crystallinity at the corresponding increased PAr content. 相似文献