The Ulm Calorimetry Conference, which is held every other year, took place for the fourth time in April 1981. The methods of calorimetry are now well established in many fields of natural science, and therefore numerous applications in physics, chemistry, biology and medicine were discussed between about 70 scientists from Germany (F.R.G.), Austria and Switzerland. A total of 24 lectures and several posters were presented, 13 of these are printed in this issue, most of the others have already been printed elsewhere.
The conference was organized by the Sektion für Kalorimetrie of the University of Ulm in cooperation with the Institut für Werkstoffkunde of the University of Braunschweig. We express our thanks to all authors who have contributed papers to this issue of Thermochimica Acta and to the editor and the publishers of this journal for their cooperation. Last but not least we acknowledge our gratitude to H.G. Wiedemann (Greifensee) who has already helped us to publish the results of the Ulm Calorimetry Conference for the third time. Without his involvement there would not have been a special issue of Thermochimica Acta.
The 5th Calorimetry Conference will be held again at Ulm in 1983.
G.W.H. Höhne (Ulm)
W. Hemminger (Braunschweig)

(Foreword, Thermochimica Acta 49 (1981) vii)

• Sektion Kalorimetrie der Universität Ulm
• Institut für Werkstoffkunde und Herstellungsverfahren der Technischen Universität Braunschweig