Fractionation definitions

CKN (1993). Workplace Atmospheres—Size fraction Definitions for Measurements of Air-home Particies. tiN 481. 

ISO i) I 992) Air Quality—Particle Size Fraction Definitions for Health-Related Sampling. ISO/ Cl) 7708 International Standardization Organization, Geneva. 

With proper design and implementation, however, it is possible to construct a self-sorting system whose behavior is different from its components [33c]. For example, consider the simple system comprising two hosts (A and B) and two guests (M and N) that can form four possible host-guest complexes (AM, AN, BM, and BN). We fix the total concentrations of hosts A and B ([A J and [B J) at 1 mM and choose the four equilibrium constants such that host A (KT-fold) and host B (10-fold) both prefer guest M (Scheme 4.7). The various mole fraction definitions (Scheme 4.7c) are used to construct a plot (Scheme 4.7d) of the composition of the mixture as a function of total guest concentration ([M J = [Nj J). When [AjJ = [Bj J > = [Nj j], complexes AM and BN dominate because... 

Scheme 4.7 Stoichiometry-induced partner displacement in a four-component mixture (a) equilibria considered, (b) constraints imposed, (c) mole fraction definitions, and (d) a plot of mole fraction versus guest concentration ([M ] = [N ]).

ISO 7708 1995 Air quality - Particle size fraction definitions for health-related sampling. EN 481 1993 Workplace atmospheres - Size fraction definitions for measurement of airborne particles. 

The previous discussion stated that the average molecular weight of a mixture W g may be expressed in terms of both component mole fractions x, and component mass fractions z,. Since mass fractions are used extensively in this chapter, it is useful to understand how Wjjyg may be expressed in terms of z,. Hence from the mole fraction definition of W g, show that Wavg(z) = (ziAVi -E Z2AV2 -E -E z /W )-i... 

Most of the oil that settled with sand on the top of the sand pack was extracted by heating it with water. Also, this oily fraction definitely has a higher density than the rest of the crude oil, indicating the possible presence of heavy metals, such as vanadium, nickel, or sulfur. Also, the oily portion that separated after heating which rose to the water surface could be crude residuum. The heavier oily material indicates a portion that is complexed with heavy metals and sulfur. 

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