Accession Number : AD0678082

Title :   EVALUATION OF TENTATIVE STANDARDS FOR DIFFERENTIAL THERMAL ANALYSIS.

Descriptive Note : Final technical rept.,

Corporate Author : MONSANTO RESEARCH CORP DAYTON OHIO

Personal Author(s) : Garn,Paul D.

Report Date : SEP 1968

Pagination or Media Count : 40

Abstract : As part of the task of the Committee on Standardization of the International Conference on Thermal Analysis, selected crystallographic phase transformations were evaluated for possible use as temperature standards in dynamic systems. Solid(1) = solid(2) transitions were selected as compared to meltings because many apparatuses, in their ordinary manner of use, may be plugged or otherwise fouled by the occurrence of a liquid phase. The materials were tested in a commercially available furnace assembly but with electronic gear assembled in a manner permitting especially good delineation of the peak parameters. The data obtained showed that superheating and/or supercooling are very common phenomena. Even though most data show good reproducibility within sets, the variation with heating or cooling rate differs greatly from compound to compound. (Author)

Descriptors :   (*DIFFERENTIAL THERMAL ANALYSIS, STANDARDS), TEMPERATURE CONTROL, PHASE STUDIES, SUPERCOOLING, DIAGRAMS

Subject Categories : Physical Chemistry
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE