Page 244 - Applied Pharmacognosy
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•If sample components have wide boiling range ----Temperature
programming unit is used-
The temperature is changed with time during the analysis (Programmed
temperature GC.
(Isothermal GC ) (Programmed temperature GC
Problems due to incorrect operating temperature
•low temp.(minimal) ----------- ↑tR , more retained
----------- excessive ↑tR & broad, ill defined peak
•Too low temp.
•High temp. ---------- ↓tR (reduction in tR) ----- ↓ resolution of components.
•Too high temp.
--------poor resolution , peak overlapping
---------bleeding of st. liquid (not in FSOT or GSC)
Use correct operating temp. to solve these problems .
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