Darwin J. Mead

Infra‐Red Analysis of Two Component Systems

Two beams from an infra‐red source are focused on opposing thermocouples which are connected in series to a galvanometer. Rocksalt cells containing identical compounds A are placed in each beam, and the galvanometer is set to zero by a shunt resistance across one of the thermocouples. Then if the composition in one cell is changed by addition of another compound B, a galvanometer deflection is observed, if the integral of transmission times radiation curve is different for pure A and for mixtures of A and B. Several examples are given, showing galvanometer current as a function of composition from pure A to pure B in the second cell, while pure A is kept in the first cell. The device thus permits a simple analytical method for two component systems.