The phase images of natural rubber / poly(butadiene) (NR/BR) blend were observed at various temperatures by the dynamic force mode AFM at 370 Hz. The phase separated structure of NR/BR blend was observed in the temperature range between −70 and 30 ºC, which corresponded to rubbery BR and glassy NR phases. The phase separated structure scarcely changed with temperature, however the phase contrast between BR and NR phases changed with temperature. The phase angle difference of NR and BR domains which was normalized by the phase angle of ZnO, shifted continuously with temperature. The glass transition temperatures(Tg) of each domain were obtained from the temperature dependency of the phase angle difference. The relationship between the frequency and the reciprocal Tg values, which were evaluated by AFM (370 kHz), dynamic mechanical analysis (2 – 10 Hz) and dielectric relaxation spectroscopy (10² – 10⁵ Hz), showed Vogel-Fulcher relationship.

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To reveal the relationships between structure, property, and function of protein, we have determined the various thermodynamic properties (partial specific volume, compressibility, expansibility coefficient, intrinsic viscosity, activation free energy for viscous flow, preferential solvation, and T_m, ΔH, ΔS, ΔG, and ΔC_p for conformational change) of proteins in solution with various conditions as temperature, pressure, solvents, additives, and protein modifications. The cyclodextrin (CD) destabilized the folded state of lysozyme by stabilizing the unfolded state by including hydrophobic part of unfolded state into interior of CD. The destabilization effect of CD was weaker than guanidine hydrochloride and was dependent on the interior diameter and the substituent. The strong water-dimethyl sulfoxide (DMSO) interaction caused lysozyme unfolding with increasing partial specific volume and intrinsic viscosity. DMSO was bound to lysozyme at low DMSO concentration and was preferentially excluded from lysozyme at high DMSO concentration. The sorbitol stabilizes protein through enhancing the hydrophobic interaction in protein. The molten globule state induced by sorbitol had thermodynamic properties somewhat like native state by preferential solvent interactions and osmotic pressure of the medium. Thus, thermodynamic properties can sensitively reflect the conformational changes and interactions with solvent, and hence will be an effective approach to give quantitative and valuable index to protein.

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In order to develop new proton conductor, phase diagram of Ba_1-xSr_xZrO₃ with high reliability has been established by combination of results of X-ray diffraction measurements at various temperatures and thermal analyses. The variation of crystal structures revealed by X-ray diffraction measurements at various temperatures agreed with phase boundary observed by DSC and dilatometry. The two phase coexistence region according to the first order phase transition was clarified from the variation of X-ray diffraction peak intensity of tetragonal and body-centered orthorhombic phases. Among Ba_1-xSr_xZrO₃, the highest conductivity was observed in Ba_0.6Sr_0.4ZrO₃, indicating that Ba_0.6Sr_0.4ZrO₃ was promising as mother phase of proton conducting oxide. Ba_0.6Sr_0.4Zr_0.9Y_0.1O_3-δ showed higher proton conductivity than so far reported BaZr_1-xY_xO_3-δ prepared with the same solution mixing method.

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Solubility and related phenomena constitute one of the oldest fields in physical chemistry, and also one of the most important. Given its wide scope, a short review cannot possibly be comprehensive, and I shall focus on just a few selected topics which reflect my current research interests, such as the solubility of supercritical solutes (gases) in liquids. First, I shall concisely present the thermodynamic formalism relevant for the study of nonelectrolyte solutions and indicate the most significant recent experimental results. Selected aspects of solubility data reduction and data correlation will be touched upon, including a critical discussion of some popular approximations. This will be accompanied by a survey of current estimation techniques for indispensable auxiliary quantities, such as virial coefficients and partial molar volumes at infinite dilution. One of the goals here is to clarify issues frequently overlooked and to dispel misconceptions encountered in the literature. Finally, a few experimental results obtained for dilute aqueous nonelectrolyte solutions will be discussed, and their relevance in biophysical chemistry indicated. Inevitably, pride of place will be given to the Henry fugacity (also known as Henry’s law constant) and to various key caloric quantities which may be derived therefrom through van’t Hoff analysis of high-precision solubility data.

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