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Interface. -Mechanically stable porous thick films of nanocrystalline TiO2 are prepared by coating an aqueous or ethanolic mixed paste of nanocrystalline TiO2 powder and titanium salts such as TiCl4, TiOSO4, and Ti IV alkoxides on transparent conductive glass and plastic substrates, followed by "steam-cooking" in the gas phase in an autoclave at 100°C. The prepared films exhibit high performance as photoelectrodes in dye-sensitized solar cells under fully operating conditions during strong light illumination. A conversion efficiency of 2.3% at AM1.5 is achieved. Because the preparation process of the films does not involve high-temperature sintering, non-heat-resistant substrates such as plastic film, paper, and cloth can be used, which should be beneficial not only for dye-sensitized solar cells but also for photocatalytic applications. -(ZHANG, D.; YOSHIDA*, T.; MINOURA, H.; Adv. Mater. (Weinheim, Ger.) 15 (2003) 10, 814-817; Environ. Renewable Energy Syst. Div., Grad. Sch. Eng., Gifu Univ., Gifu 501-11, Japan; Eng.) -W. Pewestorf 33-021

Cathodic electrodepositon of CuSCN thin films on F -doped Sn0 2 (FTO) substrates has been investigated in aqueous mixed solution of copper perchlorate and lithium thiocyanate. Cathodic current arose around +0.5 V vs. Ag/ AgCl and reached a plateau below ea. +0.3 V in the mixed solution. Levich analysis of the plateau current confirmed limitation of CuSCN deposition by mass transport. The current was proportional almost symmetrically to the concentrations of Cu 2 + and SCN-, suggesting that transport of their complex was responsible. Absorption spectrum of the mixed solutions indeed revealed an appearance of a new peak only when both Cu 2 + and SCN-were present. Job plot for this peak elucidated formation of 1 to l complex. As the concentration of this active species could be determined from the absorption spectra, Levich analyses at different temperatures made it possible to determine the frequency factor (Do) of and the activation energy (Ea) for the diffusion of (Cu 2 +)(SCN-) complex as 3.24 x 10-2 cm 2 s-1 and 20.1 kJ m or 1 , respectively.

This paper presents the applicability of an explicit time-domain finite element method (TD-FEM) using a dispersion reduction technique called modified integration rules (MIR) on room acoustics simulations with a frequencyindependent finite impedance boundary. First, a dispersion error analysis and a stability analysis are performed to derive the dispersion relation and the stability condition of the present explicit TD-FEM for three-dimensional room acoustics simulations with an infinite impedance boundary. Secondly, the accuracy and efficiency of the explicit TD-FEM are presented by comparing with implicit TD-FEM using MIR through room acoustics simulations in a rectangular room with infinite impedance boundaries. Thirdly, the stability condition of the explicit TD-FEM is investigated numerically in the case with finite impedance boundaries. Finally, the performance of the explicit TD-FEM in room acoustics simulations with finite impedance boundaries is demonstrated in a comparison with the implicit TD-FEM. Although the stability of the present explicit TD-FEM is dependent on the impedance values given at boundaries, the explicit TD-FEM is computationally more efficient than the implicit method from the perspective of computational time for acoustics simulations of a room with larger impedance values at boundaries.