Heat conduction calorimetry

Hansen LD, Lewis EA, Eatough DJ, Bergstrom RG, DeGraft-Johnson D. Kinetics of drag decomposition by heat conduction calorimetry. Pharm Res 1989 6 20-27. 

Oliyai R, Lindenbaum S. Stability testing of pharmaceuticals by isothermal heat conduction calorimetry ampicillin in aqueous solution. Int J Pharm 1991 73(1) 33—36. 

Hansen, L.D., Lewis, E.A., Eastough, D.J., Bergstrom, R.G., DeGraft-Johnson, D. (1989). Kinetics of drug decomposition by heat conduction calorimetry. Pharm. Res. 6,20-27. 

Chandra, D., et al.. Vanadium Hydrides at Low and High Pressure, Final Report to Tritium Science and Engineering Group, 2006, Los Alamos National Laboratory. Luo, W.R, Clewley, J.D. and Flanagan, T.B., Thermodynamics and isotope effects of the vanadium-hydrogen system using differential heat conduction calorimetry. Journal of Chemical Physics, 1990, 93(9) p. 6710-6722. 

R. Oliyai and S. Lindenbaum, Stability testing ofpharmaceuticals by isothermal heat conduction calorimetry Ampicillin in aqueous solution, Int. J. Pharm. 73, 33-36(1991). 

H.M. Shirazi, (Quartz Crystal Microbalance/Heat Conduction Calorimetry (QCM/HCC), a new technology capable of isothermal, high sensitivity, mass and heat flow measurements at a solid/gas interface., PhD Thesis, Drexel University, Philadelphia, PA, 2000. 

A Tian-Calvet heat flux calorimeter was used in the measurements described in ref. [2]. This type of calorimeter is also called isothermal [4, 5], in contrast to other kinds of calorimeter. A tutorial [6] on heat-conduction calorimetry gives a good account of the technique. Peak integration of the heat flux against time may be performed by a numerical integration method, such as Simpson s method, on a personal computer interfaced to the calorimeter [7]. 

There are many different types of calorimeters that can be used in the cement field, and some of them have many uses. The most common technique is isothermal (heat conduction) calorimetry in which the heat production rate (thermal power) from small samples of paste or mortar is directly measured. This technique is the focus of this chapter as it is the most versatile calorimetric technique in the cement field. Typical commercial instruments of this type used in the cement field are TAM Air (TA Instruments, U.S.), TCal (Calmetrix, U.S.), MC CAL (C3 Prozess- und Analysentechnik, Germany), ToniCAL III and ToniCAL TRIO (Toni Technik, Germany) and C80 (Setaram, France). 

Isothermal and semiadiabatic calorimeters both quantify cement hydration kinetics, but they do so in different ways. This is illustrated in Figure 2.1. In isothermal (heat conduction) calorimetry the heat production rate ( ) in a small sample (S) is measured by a heat flow sensor as heat is conducted to a heat sink that is placed in a thermostated environment. It is also necessary to have a reference sample (R) with the same properties (especially the same heat capacity) as the sample but without any heat production. This arrangement significantly reduces the noise in the measurements. The output from the calorimeter is the difference between the sample signal and the reference signal. 

Figure 2.1 Schematic illustrations of (a) isothermal (heat conduction) calorimetry and (b) semiadiabatic calorimetry. P thermal power R reference S sample T temperature t time.

NT BUILD 505 (2003). Measurement of heat of hydration of cement with heat conduction calorimetry. 

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