Enrichment, term defined

Separator GC/MS interface. An interface in which the effluent from the gas chromatograph is enriched in the ratio of sample to carrier gas. Separator, molecular separator, and enricher are synonymous terms. A separator should generally be defined as an effusion separator, a jet separator, or a membrane separator. 

The performance of any type of molecular separator is characterized in terms of its separation factor (enrichment) M and separator yield (efficiency) Y (8). The separator yield is defined as the ratio of the amount of sample entering the mass spectr( eter to that entering the separator, usually expressed as a percentage, it represents the ability of device to allow... 

A variety of terms or concepts have been used to classify reactions or sequences of reactions leading to enantiomerically enriched or reasonably pure compounds. During the preparation of this section, it was "discovered that very few terms are precisely defined. The typical ways of introduction are casual footnotes and references to actual examples. 

Formulas for the numbers of trays in the enriching and stripping sections at operating reflux also are due to Underwood (Trans. Inst. Chem. Eng. 10, 112-152, 1932). For above the feed, these groups of terms are defined ... 

This is a very important equation. It directly tells us that when a solute is enriched at the interface (T > 0), the surface tension decreases when the solution concentration is increased. Such solutes are said to be surface active and they are called surfactants or surface active agents. Often the term amphiphilic molecule or simply amphiphile is used. An amphiphilic molecule consist of two well-defined regions One which is oil-soluble (lyophilic or hydrophobic) and one which is water-soluble (hydrophilic). 

In this equation, c o is the concentration of solute in the feed solution at the membrane surface, and 5 is the thickness of the boundary layer. An alternative form of Equation (4.7) replaces the concentration terms by an enrichment factor E, defined as ciplcib. The enrichment obtained in the absence of a boundary layer E0 is then defined as ciplcio, and Equation (4.7) can be written as... 

Figure 5 A display of prominent exotic (presolar) noble-gas compositions (from Anders and Zinner, 1993). In the left two panels, for each isotope on the abscissa the ordinate is the ratio (to °Xe) in the HL component (left panel) or the G (formerly termed Xe-S) component (center panel), divided by the equivalent ratio in solar xenon (i.e., solar xenon would plot with all isotopes at unity on the ordinate). The HL component shows the defining characteristics of enriched heavy and light isotopes. For the G-component, the pattern is that expected for s-process (slow neutron capture) nucleosynthesis. The right panel is a three-isotope diagram analogous to Figure 4, except that both scales are logarithmic. It shows experimental limits for the R-component (formerly Ne-E(L)) and the G-component (formerly...

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