Separation scenario

The orthogonality % for any 2D separation scenario could then be calculated from Equation 12.5,... 

Another important reason for using multiple scenarios is to represent major sources of variability, or what-if scenarios to examine alternative assumptions about major uncertainties. This can be less unwieldy than including them in the model. Also, the distribution of outputs for each separate scenario will be narrower than when they are combined, which may aid interpretation and credibility. A special case of this occurs when it is desired to model the consequences of extreme or rare events or situations, for example, earthquakes. An example relevant to pesticides might be exposure of endangered species on migration. This use of multiple scenarios in ecological risk assessment has been termed scenario analysis, and is described in more detail in Ferenc and Foran (2000). 

Take advantage of opportunities to reduce the variability in individual assessments by defining separate scenarios. Make the specification of scenarios a distinct step in problem formulation. 

The isolation of paclitaxel exemplifies that most preparative separations must be downsized to a level where a limited number of individual compounds are present to ease the final purification steps. This downsizing of the separation problem can be done by crude separations or by a cascade of consecutive chromatographic separation steps. One finally ends up at a point where a multicomponent mixture with a broad concentration range of the different substances has to be fractionated to a series of mixtures. This approach is described in Fig. 4.4. In general, a mixture can be split into three types of fractions, which each represent a specific separation problem. These three fractions exemplify possible separation scenarios that differ with regard to the ratio of target products and impurities. 

The first separation scenario is the most comfortable problem. The target product is the major component in the mixture and thus it is easy to reach a yield and purity in the desired range. Thermodynamic effects can be used to displace impurities during the separation process. 

Fig. 4.4 Main types of preparative chromatographic separation scenarios.

The need of pharmacodynamic (PD) BE assessment arose in the mid-1990s, and currently there is not yet a universally accepted analysis method with a corresponding study design. Here we discuss properties of some potential study designs and analysis methods based on the dose-scale approach, under the framework of two separate scenarios broncodilation and broncoprovocation. 

As it may be seen in Fig. 1, disturbance consequences compose network system, where connections of different type of consequences are available. It means, that one type of consequences makes other type consequences, for example, some economical consequences are reason of technical consequences, etc. Any path in network system consists of different type of consequences with particular severity level. This path is treated as a separate scenario. To simulate disturbance scenarios, states of network system must be filled with probabilities. Transition probabilities from one system state to other are needed (calculation of such probabilities is explained in Chapter 4). 

Exploratory investigations have been performed for uranium-free core. Several compaction and separation scenarios have been analyzed and compared to the behaviour of EFR and reference CAPRA cores. 

The Tc curve (fig. 104) shows clear anomalies with a discontinuity in the range 13-15% Ca (hatched area) which coincides with the B A transition at 13-14% and A —> B at 14—15% (cf. fig. 93), the abrupt increase of the in-phase phonon width (fig. 101) and of the apex phonon width due to the appearance of new modes. This is additional support for the phase-separation scenario. Figure 105 shows the dependence of on oxygen content. Both Td and scale with oxygen and the data segregate in the two states A and B, indicating a correlation to superconductivity. 

Efficient pretreatment and separation scenarios for woody biomass that provide at least three major process streams for the biorefinery cellulose, hemicellulose and lignin. 

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