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Figure 2. Thermogram for filter sample containing organic carbon (OC), carbonate (CC), and elemental carbon (EC). PC is pyrolytically generated carbon or ‘char.’ Final peak is methane calibration peak. Carbon sources: pulverized beet pulp, rock dust (carbonate), and diesel particulate. Note: In the round robin study [35] discussed earlier, the actual maximum temperature in helium ranged from about 850 °C to 900 °C. Laboratories were asked to use the same maximum, but not all did. Comparable results were obtained because some differences in the thermal program do not affect the results significantly. For the purpose of standardization, use of the same maximum is recommended. An 870 °C maximum is near the middle of the range used by participants in the study.

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