Mixing quality, criteria

To raise the forecasting efficiency of prediction force of such criterion as Xi23 minimum, the amount of performance parameters determined experimentally must be reduced. For this purpose, the following expression for die quality criterion of die mixed solvent (the analogy with expression of the Flory-Huggins parameter for individual solvent-polymer system) is used ... 

To avoid the dependency of mixing quality on quadrat size and the number of particles, Aubin et al. [31] proposed an alternative method based on the analysis of spatial point patterns. This method differs from quadrat analysis mentioned above in that it is based on the distance Xi from each point to the nearest event (tracer particle) for a chosen lattice of m sample points in the domain and therefore it does not require the studied region to be divided into quadrats. The variance of the point-event distances around distance % [Equation (5.14)] provides a means to evaluate the mixedness of a system with respect to a well-mixed criterion. This predefined criterion is set hy the distance Xr, which corresponds to the scale of segregation whereby two events are considered spatially close enough to be mixed. Inthis case the variance is defined via... 

Frequently, the terms mass range and unit mass resolution are mixed up when giving a quality criterion for a mass range above 1000 Da for a quadrupole instrument (it is not obvious that a mass range up to 4000 Da, for example, is always accompanied by unit mass resolution). The effective attainable resolution for a real measurable signal of a reference compound is accurate and meaningful. 

The criterion of maintaining equal power per unit volume has been commonly used for dupHcating dispersion qualities on the two scales of mixing. However, this criterion would be conservative if only dispersion homogeneity is desired. The scale-up criterion based on laminar shear mechanism (9) consists of constant > typical for suspension polymerization. The turbulence model gives constant tip speed %ND for scale-up. 

Water Quality Criteria Acute aquatic (maximum) continuous criterion concentration for human health (4-day average) Outside mixing zone Point of water Intake... 

If the oil is of acceptable quality, the oil may be taken directly to the transesterification reactor where it is contacted with an excess of the chosen alcohol (usually methanol) and a base catalyst (usually NaOH or KOH). The transesterification reaction is conducted at about 60°C, which is a constraint set by the boiling point of methanol at atmospheric pressure. The oil is immiscible with the shorter-chain alcohols therefore, maintaining intimate contact between the two phases by providing adequate mixing is an important design and operating criterion for the reactor. It is also an important energy input that must be accounted for. 

Just when to terminate mixing is a critical question for both the quality and economic stand points. Yet, there is no universal criterion, because the optimum endpoint depends upon both formulation and requirements from the end-use. Jansen and Kraus [19] states, It is not always clear what constitutes a good dispersion. At practical black loadings complete separation of every primary structure aggregate from its neighbours is neither possible, nor would it be desirable . Therefore the endpoint must be predetermined case-by-case. 

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