Tsutomu Kumagai

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Thephotochemical reaction of [3(3)](1,3,5)cyclophane 2, which is a photoprecursor for the formation of propella[3(3)]prismane 18, was studied using a sterilizing lamp (254 nm). Upon photolysis in dry and wet CH2Cl2 or MeOH in the presence of 2 mol/L aqueous HCl solution, the cyclophane 2 afforded novel cage compounds comprised of new skeletons,(More)
We construct critical percolation clusters on the diamond hierarchical lattice and show that the scaling limit is a graph directed random recursive fractal. A Dirichlet form can be constructed on the limit set and we consider the properties of the associated Laplace operator and diffusion process. In particular we contrast and compare the behaviour of the(More)
A large amount of (all-E)-lycopene was successfully purified from tomato paste using an improved method that included a procedure to wash crystalline powder with acetone. The total yield of the pure (all-E) form was at least 30%. The melting point of (all-E)-lycopene was determined to be 176.35 °C by differential scanning calorimetry (DSC) measurements.(More)
The geometric isomerisation of (all-E)-lycopene, purified from tomato paste, was investigated in various organic solvents. Isomerisation ratios to the Z-isomers of lycopene in CH2Cl2 and CHCl3 over 24h were calculated to be 19.7% and 11.4% at 4°C and 77.8% and 48.4% at 50°C, respectively. In CH2Br2, more than 60% was attained in the first several hours,(More)
The relative configuration of the alcohol component in the title ester, C(27)H(32)O(3), has been assigned as (R) from the known configuration of (R)-(-)-2-meth-oxy-2-(1-naphth-yl)propionic acid [(R)-MαNP acid]. In the crystal structure, the C atom of the methyl group of the MαNP acid lies in the extended plane of the naphthyl ring system [methyl C atom(More)
We report an extension of the smoothed profile method (SPM) (Y. Nakayama, K. Kim, and R. Yamamoto, Eur. Phys. J. E 26, 361 (2008)), a direct numerical simulation method for calculating the complex modulus of the dispersion of particles, in which we introduce a temporally oscillatory external force into the system. The validity of the method was examined by(More)
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