The methods of Freeman and Carroll (I), Coats and Redfern (II), Sharp and Wentworth (III) and the present author (IV) are applied to five theoretical thermoanalytical data calculated for assumed kinetic parameters at various heating rates. These are a first-order reaction, a second-order reaction, two cases of random scission in main chains of polymers, and a system of two parallel competitive first-order reactions. Although methods I, II and III cannot be applied to the latter three cases, when one does apply them to these cases, nearly straight relations are observed and false unreal kinetic parameters are obtained. For the two cases of random scission in the main chains of polymers, the author's method gives correct kinetic parameters. For the last case, the increase of the apparent activation energy with increasing conversion implies that even method IV cannot be applied. The reason for these results and methods for avoiding false unreal results are discussed.

The conversion, the reduced rate of conversion dC/dΘ andΘ at the peak of derivative thermoanalytical curve of diffusion are estimated theoretically, solving the theoretical equation with an electronic digital computer. These values for chemical reactions including random degradation of polymers are also estimated and compared with those of diffusion. The conversion at the peak is utilized to elucidate preliminarily the mechanism of the process.

Two methods of obtaining kinetic parameters from derivative thermoanalytical curves are proposed. The methods are based on the general form of kinetic formulae and are applicable to general types of reactions governed by a single activation energy. One method utilizes the linear relation between peak temperature and heating rate in order to estimate the activation energy, and only the information of the rate of conversion versus the temperature is necessary. The other method needs the information of both the conversion and the rate of conversion versus the temperature, and the Arrhenius plot is made for an assumed kinetic mechanism.

In SCTA application to high polymers, we do not find remarkable and illustrative results such as found in multiple step dehydration processes of low molecular mass substances. However, some characteristic results were obtained in the application to high polymers, and three examples are described in this report.

For complex heat capacity measurements, various types of temperature modulated differential scanning calorimetry (tm-DSC) can be used. However, three factors have influence on steady state of tm-DSC and hence cause errors in complex heat capacity measurements. These factors are heat capacities along heat paths in the instrument, temperature distribution within the sample, and thermal contact among the sample, the sample cell and its holder plate. They are theoretically investigated by a set of comprehensive fundamental equations of heat balance based on a common model applicable to all existing types of tm-DSC. For heat paths in the instrument, heat loss to the environment and mutual heat exchange between the sample and the reference material are also taken into accounts, beside the main heat flows from the heat sources to the sample and the reference material. Rigorous and general solutions have been obtained, and useful relations for complex heat capacity measurements have been derived for each type of tm-DSC. Examining the solutions, new insight into tm-DSC is obtained, and errors and their correction are discussed. They are characteristic of tm-DSC types and compared with each other.

It was found that chemiluminescence (CL) of epoxy resin proceeds by a two step process. The first step is the formation of a substance causing CL and the second step is its reaction producing luminescence emission. The first step is predominant at room temperature, so that the CL-causing substance accumulates when a specimen is left in ambient atmosphere. By heating this specimen in nitrogen atmosphere, CL is observed. The total amount of CL is in a linear relation with the square root of time during which the specimen is left in ambient atmosphere. The kinetics of the second step was also analyzed.

Now we can use several temperature control modes, i.e., the isothermal run including stepwise heating and cooling, constant rate heating (or cooling), temperature control for sample thermal history, sample controlled thermal analysis (SCTA or controlled-rate thermal analysis, CRTA), temperature jump, rate jump, temperature modulation and repeated temperature scanning. Their advantages and drawbacks are reviewed with some illustrative examples, especially for application to kinetic analysis. The combined use of these varieties of temperature control mode is recommended by showing examples. Temperature modulation and repeated temperature scanning are discussed in comparison with temperature modulated DSC, and common and analogous points are elucidated. In relation to this, the possibility that an imaginary part of overall reaction rate constant in complex reaction is postulated. Finally,these modes are classified and tabulated from two viewpoints and other possible modes are shown.

Theoretical consideration has been made of the non-isothermal kinetics of consecutive reactions based on the superposition principle. In the model the first reaction product reacts to form the final product and the two reactions proceed independently. The amount of the first reaction product and the production rate of the final product have been obtained as a function of time for isothermal cases and as a function of the reduced times for non-isothermal cases.

For complex heat capacity measurements, steady state of various types of temperature modulated DSC is theoretically investigated by a set of common comprehensive fundamental equations of heat balance. Heat capacities of heat paths, heat loss to the environment and mutual heat exchange between the sample and the reference material are taken into accounts together with thermal contact effect between the cell and its holder plate. Rigorous and general solutions have been obtained, and useful relations for complex heat capacity measurements have been derived for each type of DSC. They are compared with each other to elucidate unique features of each type of DSC.

Curves obtained by controlled rate TG of polyimide film in air are quite different from those obtained by conventional constant rate heating TG. A two step mass loss was observed during the constant rate heating TG, while mass loss proceeded as a single step process in the controlled rate TG. To elucidate the cause for this difference, kinetic analysis was made, and it was found that the reaction mechanism in a lower temperature range is different from those in a higher temperature range. The lower temperature decomposition is a single step process, and the higher temperature decomposition is a two-step process. The reason for the difference is that only the low temperature single step process is observed in the controlled rate TG, while both reactions are observed in the constant heating rate TG along with the temperature increase. This speculation was confirmed by isothermal TG. These facts show us another usefulness of controlled rate TG. To analyze the three types of TG data together, the Friedman—Ozawa method was used, and it is demonstrated to be the most appropriate and reliable.

A repeated temperature scanning thermal analysis, such as temperature-modulated thermogravimetry, is a useful technique for the kinetic analysis of thermal decomposition in a defined temperature range. In this technique, repeated temperature scanning, i.e., cyclic heating and cooling in a defined temperature range, is introduced into thermal analysis. First, the kinetics for this new mode of temperature change are considered theoretically, and some useful relations for kinetic analysis are revealed. From these relations, methods for estimating kinetic parameters, such as the activation energy, the pre-exponential factor and the conversion functions, are derived. The errors in these parameters are also examined.

The history of thermal analysis is briefly reviewed, focusing on fundamental aspects, such as quantitative measurement by DTA, kinetics, purity determination, sample-controlled thermal analysis and temperature modulation. Several general trends, commonly seen in the history of thermal analysis, are also pointed out. Among these trends are new techniques, new application fields, diffusion of the techniques from research to quality assurance, computerization and robotics, infrastructure, such as standardization, etc. In this overview, new techniques and methods of thermal analysis are examined and directions of future progress are anticipated for its sound development.

TG–DTA–EGA simultaneous measurements were made for polyimide isothermally at 498 and 541°C in simulated air, in order to confirm the previously found facts by TG–DTA that below 520°C the mass loss is a single step process but above 550°C it proceeds by a two step process. All detected volatile products are carbon dioxide, carbon monoxide, water, nitrogen and nitrogen monoxide at the both temperatures, but the volatilization behavior at 541°C is different from that at 498°C, as was expected from the previous results. Thus the previous postulate was confirmed. However, because volatilization of water at 498°C differs from that of nitrogen monoxide, the process in the lower temperature range really proceeds by a two step process. On the other hand, at 541°C the volatilization rates of all products change similarly to each other and also to the mass loss curve and the DTA curve.

The steady state of temperature modulated power compensation DSC has been theoretically investigated for measurements of complex heat capacity, taking accounts of heat capacities of heat paths, heat loss to the environment, and mutual heat exchange between the sample and the reference material. Thermal contact between the sample cell and the cell holder is also taken into accounts. Rigorous and general solutions are obtained. From these solutions application of the technique to heat capacity measurements is discussed.

Modulation of heat flux DSC can be made by modulated light irradiation to the cells or the cell holders. For this type of temperature-modulated DSC, a theoretical approach has been tried to study steady state and hence its application to heat capacity measurement. In this approach, additional heat flows, such as mutual heat exchange between the sample and the reference material and heat loss to the environment, are taken into account together with heat capacities in the heat paths, which have the effect of amplitude decrement and phase shift of the oscillation. The effect of thermal contact between the cell and the cell holder is also considered. The results are compared with the results for other types of temperature-modulated DSC made by similar approaches to make clear the features of this type of temperature-modulated DSC.

The steady state of temperature modulated heat flux DSC, in which the sample temperature is controlled at a fixed frequency, a fixed amplitude and a constant underlying heating rate, is theoretically investigated for complex heat capacity of the sample, taking accounts of heat capacities of heat paths, heat loss to the environment and mutual heat exchange between the sample and the reference material. Rigorous and general solutions for the temperature difference oscillation are obtained in relation to the sample temperature as a reference oscillation. The results are quite different from those obtained in functions of the heat source temperature as a reference oscillation. From these solutions, application of the technique to heat capacity measurements is discussed.

The present paper describes experimental and computer simulation results for horizontal U-tube latent thermal storage units with a eutectic of sodium hydroxide-sodium nitrate. Through 1000 melting-freezing (charge-discharge) cycle tests on two 30 kWh scale storage units of bare-tube and finned-tube stypes, the heat transfer characteristics were evaluated. Computer simulations of both types of storage units were performed with a two dimensional model. For the finned-tube type, the effect of fin was included in the effective thermal conductivity of molten salt around the tubes. The calculated results were in good agreement with experimental ones. The heat transfer characteristics were evaluated for various storage units with different parameters such as number of passes, and number of heat transfer pipes.

水酸化ナトリウム-硝酸ナトリウム系, 水酸化ナトリウム-亜硝酸ナトリウム系の溶融塩は, 200～300℃ で最も有望な潜熱蓄熱材料であるが, これを蓄熱材料として用いる上で解決すべき課題の一つは, 蓄熱器構造材料との共存性である.本報では, まず10種類の金属材料と溶融塩との共存性について, 試験片を用いた浸漬試験による実験的な検討, さらに炭素鋼に的を絞って行った, 溶融塩の純度による共存性への影響に関する実験結果について報告を行う.本研究の結果では, 炭素鋼が最もよい共存性を示し, 蓄熱器構造材料としての利用の可能性が確認できた.また, 溶融塩の不純物の影響としては, 特に水酸化ナトリウム中の塩化ナトリウムの影響が重要であることを示した.

各種の充てん材を分散させたエポキシ樹脂の有効熱伝導率を測定し、 充てん材の種類、 体積分率、 粒子形状、 粒子配向状態との関係を調べた。 さらに、 粒子が均一にランダムに分散している場合につき、 有効熱伝導率を推定するための代表的な理論との比較を行った。

Differential scanning calorimetry was applied to the evaluation of binary eutectic mixtures and compounds of NaOH with NaNO 3 or NaNO 2 as latent heat thermal energy storage materials. There are two compounds and three eutectic mixtures consisting of NaOH and NaNO 3 and one compound and two eutectic mixtures consisting of NaOH and NaNO 2 . The heats of fusion of all compounds and mixtures were more than 200 J g −1 . The thermal behaviour of these materials was observed, and some compounds and mixtures show a great tendency to supercool. The specific heat capacity was also measured. Because the eutectic mixture 18.5 mol.% NaNO 3 -81.5 mol.% NaOH is the most promising material for use in a nuclear power plant, this mixture made from industrial products was examined further. After 1000 cycles of melting and crystallization in bench-scale equipment the material shows little change.