Indium standard

Glass transition temperatures of the uv-hardened films were measured with a Perkin Elmer Model DSC-4 differential scanning calorimeter (DSC) that was calibrated with an indium standard. The films were scraped from silicon substrates and placed in DSC sample pans. Temperature scans were run from -40 to 100-200 °C at a rate of 20 ° C/min and the temperature at the midpoint of the transition was assigned to Tg. 

The thermal properties of benzoic acid were evaluated using simultaneous differential thermal analysis (DTA) and thermogravimetric analysis (TGA). This work was performed on a Shimadzu DT-30 Thermal Analyzer system, which was calibrated using indium standard. Using a heating rate of 10°C/min, the thermograms presented in Figure 3 were obtained. 

A schematic of a DSC sample holder assembly and instrument is shown in Figure 3.9 and a typical DSC curve for indium (standard) is shown in Figure 3.10. 

Differential Scanning Calorimetry. A Perkin-Elmer Model DSC-IB calorimeter was used to examine crystallinity by measuring areas under the fusion curve as a function of elastomer composition and processing variables. Areas of endotherms were calibrated against an indium standard and the crystallinity calculated using a value of —138 J/g for a 100% crystalline polypropylene polymer (II). 

Differential scanning calorimetric runs were conducted on a Du Pont Thermal Analyzer (Model 9900) at an arbitrary heating rate of 10°C/min. Indium standard was used for temperature calibration. 

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. 

For the DSC measurements a Netzsch DSC 200, operating in dynamic mode, was employed. Samples of ca. 4 mg weight were placed in sealed aluminium pans. The heating/cooling rate of 10 K/min was applied. Argon was used as an inert gas with flow rate 30 cm /min. Prior to use, the calorimeter was calibrated with mercury and indium standards an empty aluminium pan was used as reference. Liquid nitrogen was used as a cooling medium. 

Thermal phase transition temperatures (TJ and enthalpies (AH) were measured with a DuPont DSC 2910 at a heating rate of 2 C/min. A 10 mg sample was loaded in a sealed aluminum pan and pre-equllibrated at 5 X for 10 minutes prior to heating. The enthalpy of the transition was calculated from the area under the curve using an indium standard. 

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. 

Diflerential Scanning Calorimetry (DSC). Calorimetric measurements were carried out by means of a Perkin-Elmer DSC8500 instrument equipped with an Intracooler 2 sub-ambient device and calibrated with purity indium standards. In order to measure the transitions of the nanoparticles, the external block temperature was set at —100 °C. A lyophilized solid powder of nanoparticles was used as sample with weight c.a. 2 mg. The powder was enclosed in aluminum pans and heated from -20 to 200 °C at a rate of 20 °C/min. Bulk sample was measured as received, enclosed in aluminum pans. 

The most common procedure is to run an indium standard under the normal test conditions and measure the heat of fusion value and melting onset temperature. These values are then compared with literature values and a check made against accepted limits. For many industries limits of 0.5°C for temperature or 1% for heat of fusion maybe accepted, though tighter limits of 0.3°C and 0.1% may also be adopted. The choice of limits depends on how accurate you need to be. Indium is the easiest standard to use because of its stability and relatively low melting point of 156.6°C, which means it can often be reused, provided it is not heated above 180°C. 

C for 5 min and then quenching to -30 C. Temperatures and enthalpy wae cahbrated using an indium standard. 

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