Thermal Z to E isomerization reactions of azobenzene and 4-dimethylamino-4'-nitroazobenzene were examined in three ionic liquids of general formula 1-R-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (R = butyl, pentyl, and hexyl). The first-order rate constants and activation energies for the reactions of azobenzene measured in these ionic liquids were consistent with those measured in ordinary organic solvents, which indicated that the slow isomerization through the inversion mechanism with a nonpolar transition state was little influenced by the solvent properties, such as the viscosity and dielectric constant, of ionic liquids. On the other hand, the rate constants and the corresponding frequency factors of the Arrhenius plot were significantly reduced for the isomerization of 4-dimethylamino-4'-nitroazobenzene in ionic liquids compared with those for the isomerization in ordinary organic molecular solvents with similar dielectric properties. Although these ionic liquids are viscous, the apparent viscosity dependence of the rate constant could not be explained either by the Kramers-Grote-Hynes model or by the Agmon-Hopfield model for solution reactions. It is proposed that the positive and the negative charge centers of a highly polar rotational transition state are stabilized by the surrounding anions and cations, respectively, and that the ions must be rearranged so as to form highly ordered solvation shells around the charge centers of the reactant in the transition state. This requirement for the orderly solvation in the transition state results in unusually small frequency factors of 10(4)-10(7) s(-1).

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It is generally difficult to measure complex shapes such as stairs with high accuracy for indoor environment scanning by the robot. Therefore, we consider the three-dimensional (3D) reconstruction of stairs using Structure from Motion (SfM) and Multi-View Stereo (MVS) which perform 3D reconstruction from images acquired by the robot vision. In this study, we verify whether it is possible to acquire a 3D reconstruction result of stairs by using images shot while ascending and descending the stairs as input to the reconstruction method. To calculate the accuracy of the reconstruction result, we use 3D computer graphics software to generate artificial image data to be applied to the 3D reconstruction. Experimental results show that 3D reconstruction results of the stairs are more accurate by applying both images shot when ascending and descending stairs to the 3D reconstruction methods.