SCANNING TRANSITIOMETRY

Scanning transitiometry is a relatively new technique which is based o n inducing a thermodynamic change by scanning at a low rate one of the independent thermodynamic variables (p, V or T) and keeping automatic ally constant the other independent variable. From the output signals recorded simultaneously (rate of heat exchange and the variations of t he mechanical variable, volume or pressure) a respective pair of therm odynamic derivatives is obtained simultaneously as a function of the s canned variable. The actual instruments operate over the temperature r ange from 200 to 550 K and over the pressure range up to 400 MPa. Typi cal examples of applications of the technique in investigation of phas e transitions in organic substances and liquid crystals under various conditions are presented. Possible future applications in solving vari ous problems in biotechnology and in physics and physical chemistry ed ucation are emphasized.