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51.
Hexagonal-pillar shaped pure Fe single crystal whiskers with six {1 1 0} side planes were obtained by means of chemical vapor deposition. Atomically resolved scanning tunneling microscopy images obtained on the {1 1 0} surface showed a quasi-hexagonal atomic array with mesoscopic-range periodic height modulation of about 1/3 of an atomic step. This height modulation was found to be a result of an interference between the quasi-hexagonal top-layer and the sub-surface bcc-Fe{1 1 0} layer. Unit vectors of the mesoscopic-range modulation turned out to be expressed as , where and are the primitive vectors of the two-dimensional atomic array in the top-layer and those in the sub-surface layer, respectively. The two-dimensional density of atoms in the top-layer is slightly higher by 0.46% than that in the sub-surface layer. 相似文献
52.
Hirotaka Mizoguchi 《Tetrahedron letters》2009,50(26):3432-16910
Based on the analysis of the mechanism of aerobic oxidation of alcohols using Ru(NO)-salen catalyst, we designed a new complex, Ru(PPh3)(OH)-salen 3, which was proved to be an excellent catalyst for chemoselective aerobic oxidation of primary alcohols to the aldehydes in the presence of secondary alcohols under ambient and non-irradiated conditions. Complex 3 was also successfully applied to the oxidation of 1-phenyl-1,n-diols to the lactols or the n-hydroxy aldehyde. It is of note that selective oxidation of primary alcohols was achieved even in the presence of activated secondary alcohols. 相似文献
53.
Tomohito Kameda Katsuaki Imai Guido Grause Tadaaki Mizoguchi Toshiaki Yoshioka 《Polymer Degradation and Stability》2009,94(9):1595-1597
The dehydrochlorination of PVC in the presence of NaOH was investigated in different diols. Diethylene glycol (DEG), triethylene glycol (TEG), and propylene glycol (PG) were found to be effective in accelerating the dechlorination of PVC. The dehydrochlorination was promoted in the order TEG > DEG > PG, which was in agreement with the compatibility between PET and the diol. Compatibility resulted in an improved penetration of the PVC particle by the solvent, leading to the acceleration of the dehydrochlorination. The dehydrochlorination of PVC in NaOH/diol followed first-order kinetics, confirming the progress of the reaction under chemical reaction control. The apparent activation energies were 82 kJ mol−1, 109 kJ mol−1, and 151 kJ mol−1 for TEG, DEG, and PG, respectively. The lower the activation energy became the faster the dehydrochlorination of PVC proceeded. 相似文献
54.
Ma G Li W Dou D Chang X Bai H Satou T Li J Sun D Kang T Nikaido T Koike K 《Chemical & pharmaceutical bulletin》2006,54(8):1229-1233
Five new monoterpene glycosides, rhodiolosides A-E (1-5), were isolated from the roots of Rhodiola rosea (Crassulaceae). Their structures were elucidated as (2E,6E,4R)-4,8-dihydroxy-3,7-dimethyl-2,6-octadienyl beta-D-glucopyranoside (1), (2E,4R)-4-hydroxy-3,7-dimethyl-2,6-octadienyl alpha-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside (2), (2E,4R)-4-hydroxy-3,7-dimethyl-2,6-octadienyl beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranoside (3), (2E,4R)-4,7-dihydroxy-3,7-dimethyl-2-octenyl beta-D-glucopyranoside (4), and (2E)-7-hydroxy-3,7-dimethyl-2-octenyl alpha-L-arabinopyranosyl(1-->6)-beta-D-glucopyranoside (5), on the basis of various spectroscopic analyses and chemical degradation. 相似文献
55.
Akon Higuchi Tomoya Yoshida Takeshi Imizu Keishin Mizoguchi Zhenjie He Ingo Pinnau Kazukiyo Nagai Benny D. Freeman 《Journal of Polymer Science.Polymer Physics》2000,38(13):1749-1755
Homogeneously fullerene‐dispersed membranes were prepared under the conditions in which a 10 wt % poly(1‐trimethylsilyl‐1‐propyne) solution containing 0.5 wt % fullerene was dried under a reduced pressure of 50 cmHg at 100 °C. UV‐vis spectra and microscopic observations of the fullerene membranes indicated that the fullerene was homogeneously dispersed in the membranes. The permeability coefficients of 1‐butene were found to be higher than those of n‐butane in the fullerene membranes, although the permeability coefficients of olefin gases were nearly equal to those of paraffin gases having the same number of carbon in poly(1‐trimethylsilyl‐1‐propyne) membranes containing no fullerene. Pressure dependence of permeability coefficients was clearly observed for the permeation of carbon dioxide, ethylene, ethane, 1‐butene, and n‐butane through the fullerene membranes, while no significant dependence was found for poly(1‐trimethylsilyl‐1‐propyne) membranes except for the permeation of 1‐butene and n‐butane. The pressure dependence of the permeability was explained by the dual‐mode sorption model. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1749–1755, 2000 相似文献
56.
H. Mizoguchi A. Endoh J. Jethwa B. Rácz F. P. Schäfer 《Applied physics. B, Lasers and optics》1991,52(3):195-199
A wide aperture X-ray preionized discharge-pumped KrF excimer laser has been constructed. A flat plate pulse-forming line (36 nF, 340 kV) charges a peaking capacitor (6 nF) through a rail-gap to facilitate a rapid discharge in the laser head. Collimated X-ray preionization is employed to obtain a wide and uniform discharge. The laser is intended to be used as a short pulse amplifier and results are presented when characterized as an oscillator. The active cross-section of the laser beam is 10×8 cm2 with 50 cm effective electrode length. The laser pulse energy exceeds 4.7 J in a 28 ns pulse (FWHM). 相似文献
57.
Electron spin-lattice relaxation rate Tl?1 has been measured at low frequencies 5–450 MHz in pristine trans-polyacetylene. Frequency dependence of Tl?1 gave dimensionality of diffusive motion of electron spins (neutral soliton). Relaxation mechanism was identified as dipolar and hyperfine origin based on an electron spin concentration dependence of Tl?1. 相似文献
58.
Asao Mizoguchi Kensuke Harada Mitsuaki Shirasaka 《Journal of Molecular Spectroscopy》2003,222(1):74-85
Millimeter-wave absorption spectroscopy combined with a pulsed jet expansion technique was applied to measure the internal rotation j=2-1 hot band of the Ar-HCN complex in the frequency region of 147-287 GHz. In total 153 rovibrational lines, split into hyperfine components due to the nitrogen nucleus, were assigned to the Σ2-Σ1, Σ2-Π1, Π2-Σ1, Π2-Π1, Δ2-Σ1, and Δ2-Π1 subbands. A set of molecular constants for the Σ2, Π2, and Δ2 internal rotation substates, including subband origins, rotational constants, nuclear quadrupole coupling constants, and Coriolis interaction constants, was determined. The internal rotation energy for the Σ2 state, 412.8949 GHz, is higher than those for the Π2 and Δ2 states, 392.3974 and 355.9570 GHz, by 20.498 and 56.938 GHz, respectively, in contrast to the Σ1 state located by 17.094 GHz lower than the Π1 state, the anisotropy of potential energy surface affecting the j=2 and j=1 states differently. The rotational and quadrupole coupling constants in the j=2 excited state are quite different from those in the ground state, indicating drastic change in the average structure in the j=2 state from the ground state. The determined molecular constants were compared with those calculated from the potential energy surface computed at the CCSD(T) level. 相似文献
59.
Yoshinori Kamiya Takuji Hirose Keishin Mizoguchi Yasutoshi Naito 《Journal of Polymer Science.Polymer Physics》1986,24(7):1525-1539
A gravimetric method for determining precisely the solubility of gases in polymers at high pressure is described. The solubilities of N2 and CO2 in low-density polyethylene (LDPE); CO2 in polycarbonate (PC); and N2, CH4, C2H6, and CO2 in polysulfone (PSUL) have been measured as a function of pressure up to 50 atm. Most of the measured sorption isotherms agreed closely with published data, but reproducible and time-dependent hysteresis in the sorption of CO2, C2H6, and CH4 in glassy polymers, PC, and PSUL, was observed in this study for the first time. Like the well known conditioning effect of high-pressure CO2 on the sorption capacity of glassy polymers, these hysteresis phenomena are believed to be due to the plasticizing effect of sorbed gases. On the basis of the current data, the dual-mode sorption model including the plasticization by sorbed gas is discussed and a primitive equation for the concentration of sorbed gases in a quasiequilibrium state of sorption or desorption is proposed. 相似文献
60.
M. Seto Yu. Maeda T. Matsuyama H. Yamaoka H. Sakai S. Masubuchi S. Kazama K. Mizoguchi K. Kume 《Hyperfine Interactions》1992,68(1-4):217-220
The129I Mössbauer spectroscopy has been applied to iodine-doped highly conducting polyacetylene. For the unstretched polyacetylene films, the iodine species of I?, I 3 ? and I 5 ? are observed. The polyiodides have symmetrical charge population. In addition to these anions, a small amount of iodines is covalently bonding to the carbon atoms, breaking the double bonds of the main chain. For the stretched polyacetylene films, the measurements were done under the condition that the stretch direction was parallel or perpendicular to the direction of incident ψ-rays. The relative change of the intensities of the Mössbauer quadrupole-split lines reveals the alignment of the polyiodine anions in the stretched film. 相似文献