No abstract

The effects of electrification processes on ice nucleation on an octadecanethiol (ODT) coating were investigated under two different conditions. Electrification provides the driving force of the movement to the three-phase contact line. This change promotes ice nucleation on the supercooled water droplet. In contrast, electrification before cooling inhibits freezing, probably because of the limitation of orientational freedom by the interaction between the surface charge and the dipole moment of water molecules.

A potassium titanium phosphate, KTi 2 (PO 4 ) 3 , and two types of hydrated titanium phosphates, α-Ti(HPO 4 ) 2 •H 2 O and γ-Ti(PO 4 )(H 2 PO 4 )•2H 2 O, were prepared by hydrothermal reaction using a layered lepidocrocite-type titanate as a starting compound. When layered lepidocrocitetype K 0.7 (Li,Ti) 2 O 4 (Lss; Ohtsuka Chemical Co., Ltd.) was used at a reaction temperature of 180°C, KTi 2 (PO 4 ) 3 was obtained. The crystal structure of KTi 2 (PO 4 ) 3 was a NASICON-like rhombohedral one with a low thermal expansion coefficient. The thermal expansion coefficient of KTi 2 (PO 4 ) 3 was determined using synchrotron X-ray powder diffraction data (SRXD), and the thermal expansion coefficients for the a-axis, c-axis and unit cell volume were −2.82 x 10 −6 , 7.16 × 10 −6 and 1.49 × 10 −6 K −1 , respectively. Two types of layered titanium phosphates, α-Ti(HPO 4 ) 2 •H 2 O and γ-Ti(PO 4 )(H 2 PO 4 )•2H 2 O, were prepared by hydrothermal reaction using protonated titanate (Lss-H) derived from lepidocrocite-type potassium titanate (Lss) by the ion-exchange reaction.