Thermal analysis and calorimetry are indispensable for the safer process development. In this paper application of thermal analysis and calorimetry technique for evaluation of potential hazard of chemical substances and thermal risk assessment of chemical process are introduced. Based on the results of thermal analyses, heat flow calorimetry and highly sensitive isothermal calorimetry hazard criteria of heat of reaction for chemical substances and risk criteria of adiabatic temperature rise and time to maximum rate for chemical processes are indicated.

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The artificial proteins, whose functions can be altered with the specific external inputs (pH, metal ions, ligands, etc.), would have large applications, for ligand-specific sensor-proteins, site-selective protein-drugs, tools to examine natural protein functions, and so on. Here we supply one of the methodologies to design such artificial proteins, especially from the protein engineering background. We designed the de novo coiled-coil proteins whose tertiary structures are altered from random coil to bundled structure by the specific external input. By insertion of the coiled-coil proteins into target natural proteins, we succeeded to construct the peptide-ligand-dependent RNA hydrolysis enzyme and metal-ion-dependent green fluorescent protein.

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We describe the thermodynamic stability of a hyperthermophilic protein with respect to the equilibrium and kinetic aspects. The stabilization mechanism of a hyperthermophilic protein is found to be characterized by its slow unfolding and this appears to be a common characteristic of hyperthermophilic proteins. It was shown that the buried hydrophobic residues contribute to the kinetic robustness. Furthermore, we discuss whether some concepts about protein stability, which are observed in mesophilic proteins, are applicable to the hyperthermophilic protein.

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A theory for the nonlinear energy response to the oscillating tempearature is developed and the nonlinear ac specific heat is defined. The theory is applied to the glass forming model with the free energy landscape picture and the characteristics of the linear and nonlinear ac specific heats in the glass forming materials are shown: (1) The width of the imaginary part of the 1st order ac specific heat broaden and the frequency at the peak of the imaginary part shifts to the low frequency region as the temperature decreases below the glass transition point. (2) The nonlinear ac specific heat, which is defined from the nonlinear energy response to the oscillating temperature, shows the anomally at the glass transition point and diverges at the Vogel-Fulcher temperature in the glass forming model. This divergence behavior is similar to that of the nonlinear magnetic susceptibility of the spin glasses. In this paper, the free energy landscape picture is briefly introduced and the characteristics of the linear and nonlinear ac specific heats are explained.

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