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51.
52.
Yoshiki Nakata Kunio Tsuchida Noriaki Miyanaga 《Optics and Lasers in Engineering》2009,47(7-8):847-849
Combined periodic structures composed of micron-sized periodic structure and nano-sized quasi periodic structure were generated on Ni–Ti target by multiple shots of interfering femtosecond laser beams. The micron-sized structure was generated by the interference pattern of four beams, and the nano-sized quasi period was generated due to the multiple shot effect of femtosecond laser. The structures were investigated in detail by two-dimensional fast Fourier transform (2D-FFT). The power spectra showed small spots and fuzzy spots due to precise period and quasi period, respectively. The most major size of the quasi periodic structure was 580 nm. 相似文献
53.
T. Matsuo T. Maekawa A. Inaba O. Yamamuro M. Ohama M. Ichikawa T. Tsuchida 《Journal of Molecular Structure》2006,790(1-3):129
The heat capacities of HCrO2 and DCrO2 have been measured at temperatures between 5 and 360 K. A lambda anomaly occurred at 320 K for DCrO2 but not for HCrO2. Infrared spectra were recorded at temperatures between 5 and 405 K. The spectrum of DCrO2 changed at 320 K with respect to the peak wave-number and splitting of some of the vibrations, while those of HCrO2 depended smoothly on temperature. These experimental results are discussed in terms of a deuteration-induced phase transition. 相似文献
54.
Eishun Tsuchida Yoshihito Osada Kei Sanada 《Journal of polymer science. Part A, Polymer chemistry》1972,10(11):3397-3404
The interaction between sodium poly(styrene sulfonate) (NaSS) and side-chain charged polycation polymer (pendent type) or main-chain charged polycation polymer (integral type) has been studied. It was found that the polyion complex (the reaction product of these polyelectrolytes) of pendent–pendent type has an equimolar composition at any mixing ratio of two component polymers. However, a polyion complex of integral–pendent type can form a water-soluble complex with a ratio of [polycation]/[polyanion] = 1/3, in addition to a complex with a equimolar composition. The mechanism of formation of this specific complex is discussed. 相似文献
55.
Iyota H Tomimitsu T Sugii R Motomura K Aratono M 《Journal of colloid and interface science》2004,273(1):73-79
Miscibility of hexanol and dodecylammonium chloride (DAC) in adsorbed films and micelles was investigated by evaluating the compositions of the adsorbed films and micelles from surface tension measurements. Judging from the phase diagram of adsorption, negative azeotropy of adsorption was observed for the mixed adsorption of hexanol and DAC at water/air interfaces. The nonideal mixing in the adsorbed film was clarified using excess functions of adsorption. Interaction between hexanol and DAC in the adsorbed film was compared with that between other alkanols and surfactants. It was found that the range of azeotropes is narrower for the hexanol-DAC mixture than for the heptanol-octylsulfinylethanol mixture, because interaction between different species in an adsorbed film is weaker in the former than in the latter. 相似文献
56.
57.
The crystal structure of [{O=VV(salen)}2(mu-F)][VIVO(salen)][BF4].(CH2Cl2)x revealed a hollow cavity with a diameter of 5.3 A that penetrates through the crystal, and a remarkable cyclic chain of the [VO(salen)] unit, a motif that has never been fashioned from oxometal building blocks. These features endow the crystal with a molecular sievelike property for the rapid, reversible, and size-selective absorption of guest CH2Cl2 molecules. 相似文献
58.
Treatment of sulfur-substituted aromatic lactams with carbonyl compounds in the presence of samarium(II) diiodide was found to undergo novel tandem desulfurization and reductive coupling reactions to generate -hydroxyalkylated lactams in high yield. Stereochemistry of the coupling products was researched and the results that decreasing the steric bulkiness of the N-substituents as well as raising the reaction temperature leads to an increase of the erythro-selectivity were observed. The mechanistic origins of this stereoselectivity are also briefly documented. 相似文献
59.
Quantitative analysis of organic materials by ToF-SIMS is intrinsically difficult because of their tendency to decompose under ion irradiation. In this study, we applied principal component analysis (PCA) as a means of compensation for the spectral degradation caused by this decomposition and thus improve the accuracy of the quantitative analysis, using as models two organic additives of quite different composition and vulnerability to decomposition under ion irradiation, in polystyrene. This enables the extraction of a principal component related to their content that is independent of the decomposition. The effectiveness of this approach in quantitative analysis of organic additives content in polymers without loss in accuracy due to spectral degradation will be discussed. 相似文献
60.