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There is no one method of measurement in thermal analysis and calorimetry that can be used for all materials or to cover all the possible thermal properties and applications. A measurement method has to be selected depending on the following criteria:
- the parameter to be measured (temperature, heat, mass or length)
- sample type (solid or liquid)
- sample size
- sample reactivity (which affects choice of crucible, protective gas)
- range of temperature
- atmosphere around the sample (inert, oxidative, reducing)
- operation under pressure
- operation in a corrosive gas
- sensitivity of detection in changes of mass, heat and length
- whether a combined technique is necessary
Summery of measurement methods
Below is a short list of the different measurement methods together with a short description.
DTA and DSC techniques
| Property |
Technique |
Description |
| Temperature difference |
Differential Thermal
Analysis DTA
Link |
A technique where the temperature difference between a sample and a reference material is measured while they are subjected to the same temperature variation (heated or cooled) in a controlled atmosphere. |
| Heat Flow rate |
Heat Flux DSC |
A technique in which the difference in heat flow rate to a test sample and to a reference sample is analysed while they are subjected to the same temperature variation (heated or cooled).The detector is a plate-DSC detector. |
| Heat Flow rate |
Power compensated
DSC |
A technique in which the temperature difference between a test specimen and a reference specimen occurring through subjecting both specimens to the same controlled temperature program is compensated by appropriately adjusting the difference of heating power to the test and reference specimen. The differential heating power is recorded against temperature or time. |
| Heat Flow rate |
Calvet DSC |
A technique in which the difference of heat flow rate to the sample and to the reference sample is analysed while they are subjected to a temperature variation (heated or cooled). The detector is a cylindrical DSC detector. |
| Heat Flow rate |
Modulated DSC |
A DSC technique in which the heating is periodic or modulated, e.g. with sinusoidal or square wave heating. |
| Heat Flow rate |
High pressure DSC |
A high pressure DSC is a DSC working with the test sample under pressure. |
| Heat Flow rate |
Robotic DSC |
A robotic DSC is a DSC combined with a robot for automated investigation of several samples. |
| Heat Flow rate and RX spectrum |
DSC-RX |
A DSC-RX is a DSC combined with an X-ray detector. |
| Heat Flow rate |
MicroDSC |
A MicroDSC is a Calvet-type DSC for thermal detection in the range of less than a microwatt, using a semiconductor-type detector. |
| Heat Flow rate |
NanoDSC |
A NanoDSC is a highly sensitive DSC for thermal detection in the nanowatt range. |
Calorimetric techniques
| Property |
Technique |
Description |
| Heat Flow rate |
Isothermal
calorimetry |
In an isothermal calorimeter, a defined exchange of heat occurs between the sample and the surroundings at a given environment temperature. The heat flow rate is determined on the basis of the temperature difference along a thermal resistance between the sample and its surroundings. |
| Heat |
Isoperibolic
calorimetry |
In an isoperibolic calorimeter, the temperature of the surroundings remains constant, while the temperature of the sample can differ from the surrounding temperature. |
| Heat |
Adiabatic calorimetry |
An adiabatic calorimeter is used to study chemical reactions and is one in which there is no net heat gain or loss during the chemical reaction. |
| Heat Flow rate |
Calvet Calorimetry
Link |
A Calvet calorimeter is a heat exchanging calorimeter with a cylindrical type detector working in isothermal and scanning modes. |
| Heat |
Drop calorimetry |
A drop calorimeter is a calorimeter into which a test piece at initially high temperature is dropped and allowed to cool, and the total heat content (enthalpy) of the test piece is measured as a temperature rise or some other parameter change in the calorimeter. |
| Heat |
Titration calorimetry |
In a titration calorimeter, a small volume of solution A is injected into the calorimetric vessel containing the solution B. The corresponding heat of interaction is measured. |
| Heat |
Flow calorimetry |
In a flow calorimeter, the sample is a flowing liquid. |
| Heat |
Solution calorimetry |
In a solution calorimeter the mixing of the samples is performed in a static (batch) mode. |
| Heat |
Reaction calorimetry |
A reaction calorimeter is designed for the investigation of
reactions between liquids or solids. The calorimetric technique can be isothermal, isoperibolic or adiabatic. |
| Heat |
Bomb calorimetry |
A bomb calorimeter is designed for measuring heat of
combustion. The sample is contained in a heavy-walled metal container containing oxygen under pressure, followed by ignition to obtain the heat of combustion of the sample. |
Thermogravimetric techniques
| Property |
Technique |
Description |
| Mass |
Mono TGA |
A technique in which the change of sample mass is analysed while the sample is subjected to a temperature variation. A mono TGA has only one furnace, for the sample. |
| Mass |
Symmetrical TGA |
A technique in which the change of sample mass is analysed while the sample is subjected to a temperature variation. A symmetrical TGA has two furnaces, one for the sample and one for the reference material. |
| Mass |
Robotic TGA |
A robotic TGA is a mono TGA combined with a robot for
automated investigation of several samples. |
| Mass |
High pressure TGA |
A high pressure TGA is a TGA (mono or symmetrical) working with the test sample under pressure. |
| Mass |
Corrosive TGA |
A corrosive TGA is a TGA (mono or symmetrical) working with the test sample in a corrosive atmosphere. |
| Mass and Temperature difference |
TGA-DTA |
In a TGA-DTA system, a DTA probe is attached to the balance to perform a simultaneous TGA and DTA analysis on the same sample. |
| Mass and Heat Flow rate |
TGA-DSC |
In a TGA-DSC system, a DSC probe is attached to the balance to perform a simultaneous TGA and DSC analysis on the same sample. |
| Mass and MS spectrum |
TGA-MS |
In TGA-MS, the TG is connected online with a mass spectroscopy detector to determine the nature and amount of volatile product emitted by the sample during a thermogravimetric experiment. |
| Mass and FTIR spectrum |
TGA-FTIR |
TGA-FTIR is a thermogravimetric analyzer (TGA) coupled online with a Fourier-Transform Infrared (FTIR) spectrometer to determine the nature and amount of volatile product emitted by the sample during a thermogravimetric experiment. |
| Mass and GC chromatogram |
TGA-GC |
In TGA-GC, the TGA is connected online with a gas chromatograph(GC) detector to determine the nature and amount of volatile product emitted by the sample during a thermogravimetric experiment. |
Thermomechanical techniques
| Property |
Technique |
Description |
| Length or volume |
Thermo-mechanical
analysis TMA |
A technique in which the deformation of a sample under non-oscillating stress is monitored against time or temperature while its temperature is programmed. |
| Length or volume |
Dynamic mechanical
analysis DMA |
A technique in which the storage modulus (elastic response) and loss modulus (viscous response) of the sample, under oscillatory load, are monitored against time, temperature or frequency of oscillation while the temperature of the sample is programmed. |
Dielectric techniques
| Property |
Technique |
Description |
| Electrical |
DEA |
Determination of the dielectric properties of the sample while exposing it to an alternating electric field. |
Thermally stimulated current technique
| Property |
Technique |
Description |
| Electrical |
TSC |
A technique which monitors, against time or temperature, the
current which is generated when dipoles change their alignment in the sample, while the temperature of the sample is programmed. |
Other techniques
| Property |
Technique |
Description |
| Magnetic |
Thermo-magnetometry |
Determination of the magnetic properties of the sample while the temperature of the sample is programmed. |
| Pressure |
Thermo-manometry |
Determination of the evolution of gas detected by pressure change while the temperature of the sample is programmed. |
| Pressure |
Thermo-barometry |
The pressure exerted by a dense sample on the walls of a constant volume cell is studied, while the temperature of the sample is programmed. |
| Optical |
Thermo-optometry |
An optical characteristic of a sample is studied while the temperature of the sample is programmed |
| Optical |
Thermo-luminescence |
The emitted light from a sample is measured while the temperature of the sample is programmed |
| Acoustic |
Thermo-sonimetry
Thermo-acoustimetry |
A technique where the sound emitted (sonimetry) or absorbed (acoustimetry) by the sample is measured, while the temperature of the sample is programmed |
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