Analysis of Cryodeposit Mixtures
Abstract
This work was concerned with the infrared (IR) spectroscopic analysis of the optical properties of cryodeposits and other materials that are important in plume contamination and related studies. The assumption that IR-active molecular band strengths in a material are directly proportional to molecular band species concentrations is incorporated in a method for the calculation of species mole fractions, which is presented along with the results of an analysis of existing AEDC cryodeposit data. The agreement of the calculated mole fractions with those obtained from chemical analysis was within 15 percent for binary component cryodeposits, but much worse for multicomponent cryodeposits. During the search for an explanation of the discrepancies, it was found that the accuracies of the densities of the cryodeposits were as crucial as those of the band strengths, and that the above assumption must be modified, in a yet unknown manner, for materials where there is a large degree of hydrogen bonding. Also, it was noted that in mole fraction determinations the use of absorption index values alone is limited to materials having at most one IR-inactive molecular species. However, the identity of IR-inactive species, which must be known in the calculation, must be available from techniques other than IR spectroscopy. A method using molar refractivities for analyzing materials with two or more IR- inactive species is outlined.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1980
- Accession Number
- ADA084548
Entities
People
- Bobby E. Wood
- J. A. Roux
- K. F. Palmer
Organizations
- Arnold Engineering Development Complex