Investigation of the requirements for plasma-induced polymerization of alcohols

We analyzed the requirements for plasma-induced alcohol polymerization by comparing the reactions of several types of aliphatic alcohols and alkanes. The experiments revealed that alcohol polymerization requires the fixation of atmospheric nitrogen into alcohol. The OH group in alcohol physically contributes to initiate the airborne plasma reactions with its permittivity. However, the group chemically works to inhibit the fixation of nitrogen and successive polymerization of alcohols. Our study demonstrates that the ratio of OH groups per weight percent of each molecule decides the feasibility of the polymerization and the properties of the polymers.     

Poly(2,7-di-n-pentyldibenzofulvene) showing chiroptical properties in the solid state based purely on a chiral conformation

Poly(2,7-di-n-pentyldibenzofulvene)s with no stereocenters, obtained by anionic polymerization using chiral 9-fluorenyllithium ligand complexes, showed intense circular dichroism in film form due purely to the chiral conformation of the main chain, while no chiroptical properties were detectable in solution.     

Ruthenium-catalyzed cyclocarbonylation of allenyl alcohols and amines: selective synthesis of lactones and lactams

Allenyl alcohols such as 4-hydroxybuta-1,2-dienes and 5-hydroxypenta-1,2-dienes having a variety of substituents undergo cyclocarbonylation in the presence of a ruthenium catalyst under mild conditions selectively to give five- and six-membered lactones in a high yield with 100% atom economy. 5-Aminopenta-1,2-dines are also cyclocarbonylated to give gamma-lactams. A possible carbonylation mechanism involving a ruthenium cluster intermediate is proposed on the basis of experimental results.     

Isomeric yield ratios of fission products in the system of 24 MeV proton-induced fission of238U

Isomeric yield ratios of 30 fission products in 24 MeV proton-induced fission of²³⁸U were measured by the use of the ion-guide isotope separator on-line. The obtained isomeric yield ratios were converted to the angular momenta of primary fission fragments based on the statistical model. The deduced angular momenta were examined from various aspects. It is found that in general the angular momentum continuously increases with the fragment mass number including the region of symmetric mass division. However, there are some exceptions. For Sn isotopes the deduced angular momenta are quite small due to the spherical shape of the nuclear shell configuration. It is also concluded from the consideration of the charge distribution that the angular momentum of fission product scatters considerably within the narrow range of mass division. The dependence of the angular momentum on the available energy of fragments at scission point indicates that the individual fragment possesses a characteristic deformation at scission and/or the deduced angular momentum is seriously affected by the particle excitation after scission.     

Cross patterning on MgO based on dislocations using femtosecond laser irradiation

We show a unique technique to form dense dislocations locally inside a MgO single crystal with a rock-salt type structure using femtosecond (fs) laser irradiation. Cross-shaped patterns of micrometer size, originating from densely introduced dislocations, are formed spontaneously around the focal point. We controlled the three-dimensional propagation of the dislocations by adjusting the pulse energy of the fs laser and NA of objective lens. The technique may open up a new field of dislocation technology for optical applications.     

Synthesis of a linear-type pentanuclear (RhIII-WVI-CuI-WVI-RhIII) sulfide cluster predicted by fast atom bombardment mass spectrometry

The positive ion FAB mass spectrum of a linear trinuclear sulfide cluster, [Cp^*RhP(OEt)₃(-WS₄CuCl] (1; Cp^* = ⁵-C₅Me₅), shows many ions heavier than the molecular ion. One of the envelopes corresponds to a pentanuclear cationic cluster of [{Cp^*RhP(OEt)₃(WS₄)}₂Cu]⁺. It has been synthesized by a reaction between [Cp^*RhP(OEt)₃WS₄] and Cu⁺ in a 2:1 molar ratio as the PF₆ salt [{Cp^*RhP(OEt)₃(-WS₄)}₂Cu][PF₆] (2 · PF₆), which is characterized by a single-crystal X-ray diffraction, EXAFS, and IR measurements.This paper is dedicated to Professor Jiaxi Lu on the occassion of this 80th birthday and in recognition of his pioneering contribution to this field.     

Electrical oscillation at a water/octanol interface in a hydrophobic container

The electrical potential oscillation at and the shape of the water/octanol interface were investigated using hydrophobic fluoroplastic containers. The interfacial potential between a water solution containing 1.5 mM sodium dodecyl sulfate (SDS) and an octanol solution containing 5 mM tetrabutylammonium chloride oscillated with an amplitude of 50-100 mV. The potential oscillation was also observed using a transparent fluoroplastic tube. The water/octanol interface shape was unchanged and no interfacial flow was observed during the oscillation. The interface shape was convex toward the octanol phase for 1.5 mM SDS, meaning that SDS adsorption to the wall was suppressed by the hydrophobic container. Therefore, the octanol system in a hydrophobic container enabled us to elucidate the electrical oscillation without any influence from the wall effect.     

The Isospin Mixing in the X(3872) Decay Spectrum

The large isospin symmetry breaking found in the X(3872) decay is investigated by looking into the transfer strength from the \({{c}\bar{c}}\) quarkonium to the two-meson states: \({c\bar{c} \rightarrow D^{0}\overline{D}^{*0}, D^{+} D^{*-} , J /\psi\omega, {\rm and} \, J /\psi\rho}\) . The widths of the \({\rho}\) and \({\omega}\) mesons are taken into account in the calculation. It is found that very narrow \({J /\psi\omega}\) and \({J /\psi\rho}\) peaks appear at the \({D^{0}\overline{D}^{*0}}\) threshold. These narrow peaks appear provided that the strength of the \({D^{0}\overline{D}^{*0}}\) component is large around the threshold. The large width of the \({\rho}\) meson enhances the isospin-one component in the transfer strength considerably, which reduces the ratio \({{\rm Br}(X \rightarrow J /\psi\omega)/{\rm Br}(X \rightarrow J /\psi\rho)}\) down to 2.5.     

Crystallization, transformation and microstructures of polymorphic fats in colloidal dispersion states

This article reviews new information about polymorphic structures, kinetic and microscopic properties of fat crystals in colloidal dispersion states such as aggregates (spherulite), oil-in-water (O/W) emulsion and water-in-oil (W/O) emulsion. The kinetic processes of fat crystallization under external factors such as different cooling rates, shear and ultrasound irradiation are reviewed. Microstructures of fats revealed by synchrotron radiation microbeam X-ray diffraction techniques in bulk and emulsion states are also reviewed for the first time.