The paper discusses some of the recent developments in simulation techniques of thermal processes such as grid refinement, grid orientation, effect of temperature on relative permeability, mathematical models, and solution methods.
The refinement process included adjustment of temperature, Au Tm ratio, pH, reaction time, [NaOH], amount of O2 in the solvent, and [BH4–] (see Experimental Procedures for the synthesis of the red product).
Refinements of the physically sensible isotropic temperature factors were unstable, but good results were obtained by refinement of overall isotropic displacement factor.
Refinement in PHENIX included XYZ-coordinate refinement, real-space refinement, and refinement of individual anisotropic temperature factors.
The model was refined further using CNS Solve (version 1.1), including simulated annealing, gradient minimization, individual occupancy, and refinement of individual isotropic temperature factors.
The effect of temperature on the structure was studied by Rietveld refinement of XRD data sets collected between 100 and 1173 K.
Literature mechanisms show reasonable agreement with the new experimental data for the 100% EtOH and the 70%/30% EtOH/DME mixtures but under-predict the reactivity of the 50%/50% EtOH/DME mixtures at temperatures below 850 K, suggesting that further refinement of the low-temperature chemistry of ethanol/DME is warranted.
Graphical results of Rietveld refinement of the high-temperature modifications of the Pr0.5Sr0.5Al0.5Ti0.5O3 structure and refined structural parameters at selected temperatures are presented in Fig. 5 and Table 2, respectively.
PXRD patterns were collected at 300 and 420 K and used for phase identification and refinement of the high-temperature phase using the FullProf suite [15].
Anisotropic temperature parameters refinement, as well as constrained refinements of the occupancy parameters of Si Al and N O pairs, were also attempted, but they all ended with unphysical values.
