The excess enthalpies for binary mixtures of o-xylene+ o-disubstituted isomers (ethyltoluene, methoxytoluene, fluorotoluene, chlorotoluene, bromotoluene, iodotoluene, tolylacetonitrile, fluoroiodobenzene, bromofluorobenzene, chlorofluorobenzene, fluoronitrobenzene, aminofluorobenzene) were measured at 298.15 K. The excess enthalpies are small for these binary systems except systems of (xylene + fluoronitrobenzene) and (xylene + aminofluorobenzene), which show larger positive excess enthalpies. The experimental results were compared according to the group contribution method UNIFAC (Dortmund), regular solution theory and COSMORS of DFT. UNIFAC predictions were positive and differed significantly from the observed results. However, excess enthalpies calculated by the COSMO-RS model showed better agreement than the others. There was a correlation between excess enthalpies and dipole-dipole interaction energy by the Keesom-Israelachvili equation.

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This review describes the defect contribution of La-doped PbWO₄ oxide ion conductors in terms of low-temperature heat capacity by comparing the sets of samples prepared by sintering and mechanical alloying (MA) methods. The heat capacities of the sintered samples with oxide ion interstitials are slightly larger than those of MA samples with essentially no interstitials around 100 K, because of the excitation of oxide ion motion as well as the lattice distortion caused by the presence of the interstitials. In addition, the variations of defect structure and heat capacity value due to milling the sintered samples are studied; oxide ion interstitials disappear rapidly during the milling process while the vacancy formation at all the general site accompanied by the softening of lattice proceed gradually. Precise heat capacity data with the help of powder density and neutron diffraction results reveal some meaningful aspects of the defect and conduction properties of the oxide ion conductors.

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Lithium secondary batteries were already used in mobile electric devices and are expected to be one of main storage devices in electric vehicles. Calorimetric approach to lithium secondary batteries during charge and discharge operation, in other words, Electrochemical Calorimetry, is one of the powerful analytical tools to understand electrochemical reaction inside the battery. For example, the configuration information of lithium-ion in the electrode structure could be detected from the electrochemical calorimetry. In addition, we could understand the quantitative degradation mechanism of the electrodes inside battery without disassembling by this approach. In this paper, we focused on our calorimetric approach to lithium secondary batteries.

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A fast multi-property measurement method using an electrical-optical hybrid pulse-heating technique has been developed for simultaneously measuring specific heat capacity, thermal diffusivity, thermal conductivity, hemispherical total emissivity, normal spectral emissivity, electrical resistivity, and Lorentz ratio of electrically conductive materials at high temperatures with better accuracy and efficiency. This technique is a combination of the electrical pulse heating method and the flash method. A thin strip specimen is directly heated by the passage of current through the specimen and the temperature of the specimen is maintained constant at a preset high temperature for several hundred milliseconds by fast feedback control of the heating current. The front face of the specimen under the brief steady state realized by the feedback control is heated by a light pulse of several hundred microseconds duration and the transient temperature response is observed at the rear face of the specimen. Time-resolved temperature measurements of the sample are carried out using a high-speed pyrometer and photopolarimeter. The details of the method and apparatus are described. Preliminary results measured by this method are presented. The primary advantage of this method is the resultant short exposure of the sample to high temperature, which can minimize the contamination of the sample and apparatus and the measurement cost and time. A further advantage of this technique is its ability of multidisciplinary investigation of both characteristics of bulk and surface of a material by using a specimen and an apparatus.

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Cosmetics are composed of numerous components, and be considered as a complex system. These components may have melting points and transition points in the manufacturing process and storage conditions. These phenomena may be involved in cosmetic functions and stability. In order to understand these phenomena, calorimetry gives us a lot of information. In this review, we discuss about oil/wax system used as lipstick. The hardness of the system depends on the solubility of wax. Their behavior was revealed by DSC measurements. It is known that O/W cream is solidified with the network structure of α-gel formed by fatty alcohols and surfactants in water phase. The α-gel is responsible for rich feeling of creams, and provides the skin moisturizing effect of creams. Formation of α-gel and suitable composition of surfactants and fatty alcohols for formation of α-gel were revealed by DSC measurements. Recently, remarkable emulsification techniques, which provide useful functions to cosmetic products by changing the size of emulsion particles, have been developed. In this article, new emulsification techniques and their functions are described in the view point of thermal property.

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