Kiyoshi Shimizu

Pressure and temperature effects on the excess deuteron and proton conductance

The limiting molar conductances Λ° of deuterium chloride DCl in D2O were determined as a function of pressure and temperature in order to examine the proton-jump mechanism in detail. The excess deuteron conductances λ°E(D+), as estimated by the equation [λ°E(D+) = Λ°(DCl/D2O) − Λ°(KCl/D2O)], increases with an increase in the pressure and temperature as well as the excess proton conductance [λ°E(H+) = Λ°(HCl/H2O) − Λ°(KCl/H2O)]. The isotope effect on the excess conductances, however, depends on the pressure and temperature contrary to the model proposed by Conway et al.: λ°E(H+)/λ°E(D+) decreases with increasing pressure and temperature. The magnitude of the decrease with pressure becomes more prominent at lower temperature. These results are discussed in terms of the pre-rotation of adjacent water molecules, the bending of hydrogen bonds with pressure, and the difference in strength of hydrogen bonds between D2O and H2O.

Formation of YAIO3 with Garnet structure

Amorphous material, which yields a YAlO3 powder, has been prepared by the simultaneous hydrolysis of yttrium and aluminum alkoxides. A phase with a garnet structure is formed as an intermediate product. The formation process of YAlO3 is described.

Pressure and isotope effects on the proton jump of the hydroxide ion at 25°C

AbstractThe limiting molar conductances Λ0 of potassium deuteroxide KOD in D2O and potassium hydroxide KOH in H2O were determined at 25°C as a function of pressure to disclose the difference in the proton-jump mechanism between an OH− (OD−) and a H3O+ (D3O+) ion. The excess conductance of the OD− ion in D2O λEO(OD-), as estimated by the equation

Formation of spinel from metal organic compounds

\lambda _E^O (OD^ - ) = \Lambda ^O (KOD/D_2 O) - \Lambda ^O (KCl/D_2 O)

Formation and transformation of alkoxy-derived BaB2O4

increases a little with pressure as well as the excess conductance of the OH− ion in H2O

Formation and transformation of SrGeO3

\lambda _E^O (OH^ - ) = \Lambda ^O (KOH/H_2 O) - \Lambda ^O (KCl/H_2 O)