pyyhkäilykalorimetria

Pyyhkäilykalorimetria, also known as swept-frequency calorimetry or differential scanning calorimetry in some contexts, is a technique used to measure the heat evolved or absorbed by a sample during a controlled process. It involves precisely measuring the temperature changes within a calorimeter as it is subjected to a controlled thermal program. This program typically involves sweeping the temperature over a defined range at a constant heating or cooling rate.

The fundamental principle is to compare the heat flow into a sample cell with that into a reference cell, which is either empty or contains an inert material. Any difference in heat flow between the two cells is attributed to a thermal event occurring in the sample, such as a phase transition, chemical reaction, or decomposition. The output of the measurement is a thermogram, which plots heat flow against temperature.

Pyyhkäilykalorimetria is widely applied in various scientific fields. In materials science, it is used to study the thermal stability, curing processes of polymers, and melting/crystallization behavior. Chemistry utilizes it to determine reaction enthalpies, activation energies, and the purity of substances. In pharmaceuticals, it helps in understanding drug polymorphism, stability, and formulation development. The technique's sensitivity and ability to provide quantitative thermal data make it a valuable tool for characterizing materials and processes.