Temperature-dependent sensing mechanisms

Temperature-dependent injection was attributed to a competitive population of low-lying state [thought to be a ligand field (LF) state] and the remote injection process. Regardless of the mechanism, the results demonstrate that sensitized electrodes can be fabricated for temperature-sensing applications. 

The mechanism of Figure 1 Is considered to be the basic route of low temperature oxidation. Basic, In the sense that deviations of the mechanism occur which are temperature dependent. 

It should be pointed out that column selectivity should frequently be understood in a very broad sense. Reliable predictions are frequently difficult. Different temperature dependence of partition coefficients for various solutes may further modify such predictions. Mixed retention mechanisms are also observed due to interactions between the solid supports and chromatographed molecules. 

The failure criteria are defined by maximum tolerable temperature dependent DoO values. As stated earlier the limits are independent of the time of re-oxidation and air flow rate. However, these parameters may be important for system operation. In intended redox cycles upon system shut-down a well defined volume of air will be applied to the anode side of the cell until the system is cooled down. If air flow rate and time of re-oxidation can be controlled together with temperature, the DoO can be minimized. This shows Fig. 6. In two sets of experiments at 600 and 800°C samples based on 1.5 mm Coat-Mix substrates were re-oxidized with a total air volume of 18 1. The air volume was applied to the cells in various combinations of air flow rate and time of re-oxidation. The results show, that it is beneficial to apply the air in the shortest possible time with the highest possible flow. At 800 C the complete re-oxidation after 60 min with a flow of 300 ml/min could be reduced to less than 75% by applying the volume in 15 min with a flow of 1.2 1/min. At 600°C re-oxidation for 120 min and a flow rate of 150 ml/min resulted in a DoO of about 80%. After 15 min with 1.2 1/min the DoO stayed under 30%. So the choice of a reasonable combination of time of re-oxidation and air flow rate can be crucial for the mechanical integrity of the cell. In this sense both time of re-oxidation and air flow rate are important parameters for intended and controlled re-oxidation. Again an explanation for this will be given in the discussion section. 

Mikhailov (1967) worked out a detailed statistical mechanical theory of the Samoilov model. In particular, he made an estimate of the temperature dependence of the mole fraction of the lattice molecules. It is puzzling to find a comment in this article saying We do not consider Samoilov s ice-like model to be one of the so-called two-structure water models, since by the very fact that we choose to classify molecules into two or more species, we have already made the choice of the mixture-model approach (in the sense of Chapter 5). 

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