Dual thermometer

In the dual slope method, referring to the Fig. 12.1, the support (Sp), with the thermometer (Th) and the sample (S), is heated by the heater (H) with a constant power I during the first phase of an acquisition. In this step, the sample temperature Ts rises from 1 to T2. Then, the power P is reduced to a value P to bring the sample back to a temperature T( 7, . During these phases, the temperatures rrise and TfM are both recorded. The two following equations describe the heating and the cooling phase respectively ... 

Pyrometric thermometers can be of the following types optical (brightness), ratio (two-color), total (wide-band), and narrow-band, whereas the fiber optic designs can be of the light-pipe, black body, dual-wavelength, crystal, gap, and fluoroptic variety. Their temperature ranges are from -40 to 4,000°C (-40 to 7,000°F), and their errors range from 0.25% to 2% FS. 

Assemble apparatus used for the reaction consisting of the three-necked flask fitted with a condenser, a thermometer and a septum. Connect the top of the condenser to the dual bank via the angled adaptor. 

This mixture is then placed in a three-necked round-bottomed flask equipped with a thermometer (0-300°C), an overhead stirrer, and an outlet tube connected by (thick-walled) tubing to a Buchner flask fitted with a Quickfit (female) joint. The conical flask is, in turn, attached to the dual-manifold system using a similar outlet tube. 

Add c/enc/r/-PE(OH)i2 (2 g, 3.29 mmol) to a flame-dried 500 mL three-necked flask equipped with a stirrer bar, a pressure-equalizing dropping funnel fitted with a rubber septum, a condenser, and a thermometer, and attached via the condenser to the dual manifold. 

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