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Ústav anorganickej chémie, technológie a materiálov

LABORATORY OF CALORIMETRY

 

New building, B-block, 5th floor, Lab No. img, Department of Inorganic Chemistry, Faculty of Chemical and Food Technology STU

 

Head: doc. Ing. Blažena Papánková, PhD.

 

Differential Scanning Calorimetry (DSC)

DSC measures the amount of energy absorbed or released by a sample as it is heated, cooled or held at a constant temperature. DSC also performs precise temperature measurements.

There are two types of DSCs:

  • Heat flux DSC

  • Power Compensation DSC

The heat flux DSC

In this design, both sample and reference pans are heated by a single furnace, which is much larger in mass than the furnaces used in a power compensation DSC. The temperature vs. time profile through a phase transition in a heat flux instrument is not linear. At a phase transition, there is a large change in the heat capacity of the sample, and this leads to a difference in temperatures between the sample and reference pan. Mathematical equations convert the signal into heat flow information.

 

 

Heatflux

 

The power compensation principle

When an event occurs in the sample material, sensitive Platinum Resistance Thermometers (PRTs) detect the change in the sample, and power (energy) is applied to or removed from the sample furnace to compensate for the change in heat flow to or from the sample. As a result, the system is maintained at a “thermal null” state at all times. The amount of power required to maintain system equilibrium is directly proportional to the energy changes occurring in the sample. No complex heat flux equations are necessary with a power compensation DSC because the system directly measures energy flow to and from the sample.

 

 

Powercomp

 

 

Additionally, power compensation DSC benefits include enhanced modulated temperature DSC (StepScan) technique and fast scan DSC (HyperDSC) for dramatic improvements in productivity, as well as greater sensitivity.

Advanteges over heat flux DSC are rapid heating and cooling rates up to 500 C/min. It increases your lab's productivity. Power compensation DSC provides the best possible

  • resolution

  • sensitivity

  • fast scan DSC using HyperDSC

  • modulated temperature DSC using StepScan

DSC is used to analyze melting, crystallization, glass transition, oxidative induction time (OIT), polymorphism, purity, specific heat, kinetic studies, curing reactions, denaturation, etc. Here are some practical applications:

 


Instrumental equipment of the Laboratory of Calorimetry

Diamond Differential Scanning Calorimeter by PerkinElmer
 
Prístroj 1
Prístroj 2
 

Instrument specifications

Features/Benefits include:

  • Unique power compensation design

  • HyperDSC, the leading fast scan DSC technique

  • StepScan, for modulated temperature DSC

  • Superior signal resolution and sensitivity

  • Highest caloric accuracy

  • Multiple cooling options for a temperature range of –170 °C to 730 °C

DSC Type

Power compensation temperature null principle. Measures temperature and energy directly, rather than differential temperature (DT).

 

DSC Cell

Independent dual furnaces constructed of platinum-iridium alloy with independent platinum resistance heaters and temperature sensors with furnace mass less than 1g.

 

Temperature Sensors

Distributed, Platinum Resistance Thermometers for best linearity.

 

Atmosphere

Static or dynamic, including nitrogen, argon, helium, carbon dioxide, air, oxygen or other inert or active gases, over full temperature range. Oxygen can be used up to 730 °C which allows easy cleaning.

 

Temperature

Range -170 °C to 730 °C

Accuracy / Precision ±0.1 °C / ±0.01 °C

 

Calorimetry

Accuracy / Precision < ±1% / < ±0.1%

 

Scanning Rates

Heating/Cooling 0.01 °C to 500 °C/min

 

Temperature Overshoot

100 °C/min < 0.1 °C

 

Cooling Times

Ambient Coolant 725 °C to 100 °C (under 4 minutes)

Liquid Nitrogen Coolant 200 °C to -150 °C (under 2 minutes)

 

Cooling Options

Ice Water 25 °C to 730 °C

Circulating Liquid -10 °C to 730 °C

Refrigerator (Intracooler) -70 °C to 730 °C

Automatic Liquid N2 (CryoFill) -170 °C to 300 °C

 

Autosampler

The Diamond DSC Autosampler can run up to 44 sample positions unattended. It has the ability to be customized through Pyris Player to meet your analysis needs and increase productivity.

 

High Pressure Cell

Extends the capabilities of the power compensation Diamond DSC design to elevated pressure measurements. Pressure range is up to 42 bar (600 psi).

 

Quality Assurance

Developed under ISO 9001