The best known of them are conventional/basic DSC, 14 microelectromechanical systems (MEMS)-DSC, 15 infrared (IR)-heated DSC, 16 modulated-temperature DSC (MTDSC), 17 gas flow-modulated DSC (GFMDSC), 18 parallel-nano DSC (PNDSC), 19 pressure perturbation calorimetry (PPC), 20 self-reference DSC (SRDSC), 21 and high-performance (HPer) DSC. In the last decades, various DSC-based techniques have been developed to improve the molecular measurements of biomolecules. 11, 13 The sample and reference are maintained at the same temperature, and the difference in thermal power required to maintain them at the same temperature is measured and plotted as a function of temperature or time. In a power-compensated DSC, the sample and reference pans are placed in separate furnaces heated by separate heaters. Where q is “sample heat flow”, Δ T is “temperature difference between sample and reference”, and R is “resistance of thermoelectric disk”. 11, 12 However, owing to the heat capacity (C p) of the sample, there would be a temperature difference between the sample and reference pans, which is measured by area thermocouples, and the consequent heat flow is determined by the thermal equivalent of Ohm's law: 11, 12 The furnace is heated at a linear heating rate, and the heat is transferred to the sample and reference pan through the thermoelectric disk. 11 In a heat flux DSC, the sample material, enclosed in a pan, and an empty reference pan are placed on a thermoelectric disk surrounded by a furnace. 10, 11īased on the mechanism of operation, DSCs can be classified into two types: heat-flux DSCs and power-compensated DSCs. 11 During a change in temperature, DSC measures a heat quantity, which is radiated or absorbed excessively by the sample on the basis of a temperature difference between the sample and the reference material. 10 In other words, the device is a thermal analysis instrument that determines the temperature and heat flow associated with material transitions as a function of time and temperature. DSC is a thermal analysis apparatus measuring how physical properties of a sample change, along with temperature against time. Amongst various types of calorimeters, differential scanning calorimeter (DSC) is a popular one. 1, 2 Calorimeters are used frequently in chemistry, 3 biochemistry, 4, 5 cell biology, 6 biotechnology, 7 pharmacology, 8 and recently, in nanoscience 9 to measure thermodynamic properties of the biomolecules and nano-sized materials. Calorimetry is a primary technique for measuring the thermal properties of materials to establish a connection between temperature and specific physical properties of substances and is the only method for direct determination of the enthalpy associated with the process of interest.
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