My synthesis was of Shell and Core arrangement. Shell is CaCO3 and Core is Heptadecane. Temperature range was from 0 to to 50°C at rate of 5°C/min. For pure Heptadecae the peaks were obtained 12°C and 25°C while heating and 5°C and 18°C while cooling.
Regarding your question "what does the straight line in DSC mean?": The flat straight line between peaks is the baseline. It shows you that the sample and reference require the same amount of heat to maintain their temperatures equal, whereas, in the case of endothermic peaks, the sample requires more heat (and in the case of exothermic peaks, the sample requires less heat) to keep its temperature equal to the reference.
DSC requires a reference pan and the sample pan in order to measure the heat flow differences, i.e. endothermic or exothermic reactions. The 'straight line, as you have put it, is the baseline showing that their is no net heat flow between the reference pan and the sample.
Straight line in DSC means that there is no endothermic and exothermic reaction is happening. the slope is zero. And here slope is Cp(specific heat).That mean the difference between the reference and sample's heat flow is zero.
Yes, I think the same. It seems like there is no endothermic and exothermic reaction. Can be justified that, there is no reaction happen at that particular temperature. Meaning that no glass transition, no crystallization and no melting happen.
The baseline (straight line) between peaks means that no physical or chemical process occurs since no endothermic, exothermic or change of Cp (like Tg) is recorded.I guess that the two phenomena are revirsible since we can see them during both heating and cooling with a shift of the temperature what is quite normal for several pheomena (like fusion and recrystallization for e.g.)
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