Page 243 - Applied Pharmacognosy
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*Chiral stationary phase -----------------
IV-Operating temperature
Depending upon boiling points of sample components
Compounds elute in order of increasing b.p.
Compound with high b.p. is the more retained by st.ph. with ↑ tR
The choice of operating temperature:
• if boiling points of sample components do n't differ greatly(closely
related with narrow b.p. range)----- constant temperature, few degree
slightly above the average b.p. of mixture components (middle point of
the boiling range)
(Isothermal GC )
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