Accession Number : AD0814190

Title :   TEMPERATURE FLUCTUATIONS IN FRACTIONAL SOLIDIFICATION OF ORGANICS,

Corporate Author : AEROSPACE CORP EL SEGUNDO CA LABS DIV

Personal Author(s) : Wilcox, W. R.

Report Date : MAR 1967

Pagination or Media Count : 20

Abstract : Temperature measurements were made inside zone melting and progressive freezing tubes. Short-term fluctuations of up to 3.7C were found. These resulted from drops falling into the melt, unsteady free convection in the melt and on the outside of the tube, and drafts in the room. We believe that these fluctuations cause impurity striations or banding and thereby reduce fractionation. In addition, variations of up to 2.5C over periods on the order of hours were observed.

Descriptors :   *FREEZING), (*ORGANIC COMPOUNDS, ZONE MELTING, DISTILLATION, ELECTROCHEMISTRY, TEMPERATURE, SOLIDS, BENZOIC ACIDS, HEAT OF FUSION, THERMAL CONDUCTIVITY, CRYSTAL GROWTH, NAPHTHALENES, LABORATORY FURNACES, MEASUREMENT, THERMOCOUPLES, OSCILLATION, GASES, INTERFACES.

Subject Categories : Physical Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE