Photo calorimeter

Pig. 28. Commercial version of the cone calorimeter. Photo Courtesy of Fire Testing Technology 2004. 

FIGURE 12.6 Photos of the LDPE/EVA filled samples (a) Hy60, and (b)Hy/MMT50 after cone calorimeter test. (From Laachachi, A. et al., Polym. Degrad. Stabil., 89, 344, 2005.)... 

Electrical resistivity measurement adopted conventional four probes method. Seebeck coefficient was measured by the standard DC method. Thermal conductivity k was calculated from density, specific heat, and thermal diffiisivity. Specific heat measurement was carried out by use of a differential scanning calorimeter (DSC model 8230, Rigaku, Japan) compared with a standard material of a -AI2O3. The values of thermal diffiisivity obtained from a differential phase analysis of photo-pyroelectric signal (AL- A 0 analysis) [9]. All measiu ements were done at room temperature. 

Thermocouple installation is important to ensure the proper temperature will be measured. Figure 5.3 shows a thermocouple located at the top of the radiant section in a process heater used to measure the temperature of fhe heater. As will be discussed later, this type of fhermocouple measurement needs to be corrected to get the actual temperature. The location of this thermocouple is important because if it is located too close to the wall, then the temperature will be lower due to the lower temperature tubes that are cooled by process fluid. That lower temperature would not be representative of the average heater temperature. Figure 5.4 shows a photo of the thermocouples used to measure the water outlet temperatures from calorimeters in a flame impingement heating study [17]. The thermocouples were positioned so that water would have to flow over the junctions, regardless of the flow rate. If the thermocouples were positioned, for example, perpendicular to a vertically downward flow of water, there is a good chance the junction would not... 

A bomb calorimeter. The reaction is carried out inside a rigid steel bomb (photo of actual disassembled bomb shown on right), and the heat evolved is absorbed by the surrounding water and other calorimeter parts. The quantity of energy produced by the reaction can be calculated from the temperature increase. 

Photo Differential Scanning Calorimetry. A modified differential scanning calorimeter (Perkln-Elmer DSC 2C) was used to determine percent conversion for various Irradiation times. This was calculated from the residual polymerization energy remaining after sav jle Irradiation. 

Figure 12.4 Photos of the residues obtained after calorimeter test of PMMA-AI2O3 at 35 KW/m. ...

There have been several successful attempts to construct photo-calorimeters, mainly to study rapid photo reactions, for example the rearrangement of rhodopsin [98]. The development of photo-calorimetry is progressing towards a differential instrument capable of studying relatively slow degradation reactions [99,100]. 

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