Differential scanning calorimetry temperature calibration

Differential scanning calorimetry (DSC) was used in investigating the curing kinetics of the unsaturated polyester resin. For the study, we used a DuPont 1090 Thermal Analyzer, equipped with a 910 DSC Module. Indium was used for temperature and calorimetric calibrations, following the procedure described in the operating meinual of the instrximent. The experimental procedure employed is very similar to that described in the literature (8-13) cind we have discussed it elsewhere (14). 

The thermal behavior of ot-chitin was examined by differential scanning calorimetry (DSC) using a DSC-25 Mettler instrument. Samples (each 5 mg) were hermetically sealed in aluminum pans and scanned over a temperature range of 0-350 °C at a scan rate of 5 °C/min. The instrument was calibrated using indium, and the calorimetric data were analyzed using STAR software (version 9). 

Differential Scanning Calorimetry. DSC scans were made at 20°C min"1 on a Mettler TA300O system equipped with a DSC-30 low temperature module. Temperature calibration was done with a multiple Indium-lead-nickel standard. An indium standard was used for heat flow calibration. Thin shavings (ca. 0.5 mm thick) were cut with a razor blade from the cross-sectional edge of a plaque. These sections contained both surface and center portions. 

Using differential scanning calorimetry (DSC) (or, less directly, differential thermal analysis (DTA)) (see Section 2.8.5., above) it is possible to measure several of the thermodynamic properties of solids and of solid state reactions. The DSC response is directly proportional to the heat capacity, Cp, of the sample, so that by use of a calibrant it is possible to obtain values of this fundamental thermodynamic property, at a particular temperature, or as an average over a specified temperature range. Other thermodynamic properties are readily derived from such measurements ... 

The temperature dependence of K for the DuPont DTA sample holder is illustrated in Figure 5.39 (106). As can be seen, the calorimetric sensitivity of the apparatus decreases with temperature that is, more heat is required per unit area. In differential scanning calorimetry, such as with the Perkin-Elmer instrument, K is independent of temperature hence, only a one-temperature calibration is required. The problem of multitemperature calibration in DTA is also eliminated in the technique of constant-sensitivity DTA proposed by Wendlandt and Williams (107). 

It is seen that the calibration constant disappears, which assumes that it is constant over the experimental conditions. The calculation is carried out using dedicated software. In some circumstances the crucible used for the sample may have to be different from that used for the calibrant. This means that a correction will be required to take into account the difference between the heat capacity of the two crucibles - readily calculated with sufficient accuracy. Measurements can be made at a series of temperatures but are meaningful only within the quasi-steady-state region of the experiment. The specific heat capacity of sapphire has been listed by ASTM in connection with the standard test method E 1269 (1999) for determining specific heat capacity by differential scanning calorimetry. 

Instrumental. All Differential Scanning Calorimetry (DSC) runs were conducted on a Perkin-Elmer DSC-7 attached through a TAC-7 Thermal Analysis Controller to a DEC computer station 325c. All runs were conducted at 10°C/min. in N2 unless otherwise stated. Thermogravimetry was run on a Perkin Elmer TGA-7 attached through the same system as the DSC. Isothermal aging of samples in sealed capillaries were conducted in the DSC cell of a DuPont 9(X) Thermal Analyzer after temperature calibration. 

Thermal Heat Capacity - The heat capacity of SiOC-N312 BN 2-D composites was measured by differential scanning calorimetry (DSC). In this test a sample of dimensions 4.24 X 4.24 X 1 mm is placed in a calibrated heating chamber along with a known heat capacity standard, and the chamber is heated at a fixed heating rate. The temperature difference between the standard and the composite is recorded, and the heat capacity is calculated from the measured temperature difference, the heat capacity of the standard, and the calibration constraints for the system. 

DIFFERENTIAL SCANNING CALORIMETRY SIMULTANEOUS TEMPERATURE AND CALORIMETRIC CALIBRATION... 

Differential scanning calorimetry is not an absolute measuring technique, calibrations are thus of prime importance. Calibrations are necessary for the measurement of temperature, T (in K) amplitude, expressed as temperature difference, AT (in K) or as heat-flow rate, dQ/dt (in J s or W) peak area AH (in J) and time, t (in s or min). Figure 4.62 shows the analysis of a typical first-order transition, a melting transition. 

Cycloaliphatic resins were prepared by complete hydrogenation of selected aromatic resins. Molecular weight data were obtained by size exclusion chromatography, using a Styragel column set with THF as the mobile phase. Calculations were based on a polystyrene calibration. Glass transition temperatures were obtained by differential scanning calorimetry from the first break on the second heat. 

Differential scanning calorimetry (DSC) investigations were performed on a Perkin-Elmer DSC-2 apparatus equipped with scanning autozero. Polymer samples and inserts (8-10 mg) and equivalent amounts of pilocarpine salts (ca. 1.0 mg) were analyzed at heating-cooling rates of 20 /min under dry nitrogen flow. Indium standards were employed for temperature calibration and enthalpy change evaluation. 

Differential scanning calorimetry (DSC) scans were acquired on a Du Pont thermal analyzer (Model 9900) with a heating module (Model 910). The heating scans were carried out from ambient temperature to 330 °C in a circulating dry nitrogen environment. Indium standard was used for temperature calibration. The heating rate was 20 C/min unless indicated otherwise. 

Test method for glass transition temperatures by differential scanning calorimetry or differential thermal analysis Standard practice for calibration of temperature scale for thermogravimetry... 

Vanden Poel, G. and Mathot, V.B.F. (2006) High-speed/high performance differential scanning calorimetry (HPer DSC) Temperature calibration in the heating and cooling mode and minimization of thermal lag. Thermochim. Acta, 446,... 

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