Rodney L Biltonen

US Patent:

42559618, Mar 17, 1981

Filed:

Oct 17, 1978

Appl. No.:

5/952155

Inventors:

Rodney L. Biltonen - Charlottesville VA
Donald B. Mountcastle - Charlottesville VA
Jaak Suurkuust - Lund, SE

Assignee:

University of Va. Alumni Patents Foundation - Charlottesville VA

International Classification:

G01K 1700

US Classification:

73 15B

Abstract:

A differential scanning calorimeter based on the heat leak principle having a reference measuring cell and a sample measuring cell symmetrically seated within a copper heat sink surrounded by an isothermal shield. Each measuring cell includes a cylindrical stainless steel ampoule which contains a test substance, a honeycombed aluminum cell frame which supports the ampoule, and a pair of thermopiles which are placed between the aluminum cell frame and the copper heat sink and which measure the temperature difference between the two. A plurality of resistive heating elements wired in series are applied to different sections of the heat sink and the isothermal shield, each heating element having a resistance respectively proportional to the heat capacity of the heat sink sections and the shield. A common current is then passed through the heating elements, thus producing a highly uniform positive temperature scan with a minimum of residual temperature gradients existing within the heat sink. The ampoules in the measuring cells are individually pressurizable whereby calorimetric data as a function of pressure can be obtained.