Two-stage PTR

The lowest temperature, reached by Gifford and Longsworth with the BPTR, was 124 K with a single-stage PTR and 79 K with a two-stage PTR (see Fig. 5.19) [78],... 

FIGURE 28.3 Mass spectra of ethyl acetate and 1,4-dioxane obtained by the two-stage PTR-MS in the one-stage mode (A) and (C), respectively, and the two-stage mode (B) and (D), respectively. Reprinted with permission from Reference [29]. Copyright 2008 Elsevier. 

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