Fractionation ratio

Liquid mol fraction ratio from apor mol fraction ratio ... 

The integration is performed graphically as shown in Figure 3.9 by plotting In gB against the mole fraction ratio XB/XA. 

Since dosage forms contain more than just active drug, it is of practical interest to understand how the various components from a multicomponent solid influence their own dissolution and release. Nelson [18] was one of the first pharma-ceuticists to ponder this question and perform the initial dissolution studies. Unfortunately, Nelson initially considered the dissolution of interacting solids (benzoic acid + trisodium phosphate), which is a more complicated and more complex situation than simple multicomponent dissolution of noninteracting solids. Nelson did show that for his benzoic acid and trisodium phosphate pellets, there was a maximum increase in benzoic acid dissolution in water at a mole fraction ratio of 2 1 (benzoic acid trisodium phosphate) and that the benzoic acid dissolution rate associated with the maximum rate was some 40 times greater than that of benzoic acid alone. 

Figure 15. Experimental torque vs. binder fraction ratio for a porous sodium carbonate mixture, from Tardos (1994).

For convenience in representing other local mole fraction ratios, we introduce additional notation as follows ... 

In addition, Hemy s law constants may be expressed as a mole fraction ratio between the air and aqueous phases (Leighton and Calo, 1981) ... 

The air into the conversion and combustion system is assumed to be composed of O2, N2, H2O, Ar. The CO2 content is negligible. The volume fraction ratios in dry and humid air between oxygen and nitrogen as well as oxygen and argon are assumed to be constant, whereas the moisture content is measured. 

The molar fraction ratio between helium and nitrogen in the flue gas was determined from gas chromatographic measurements. The molar flow of the tracer gas of helium was measured. Because Rogers applied batch methods to measure water vapour in flue gas and the helium-nitrogen ratio, the overall method become a semi-continuous method. The water vapour of the flue gas was measured batchwise by freezing it out in an U-tube placed in an acetone-dry ice mixture. 

Within the frame of the present first series of experiments it was almost always oxygen which was injected into supercritical water-methane mixtures. There were several reasons for this first choice. One of these was the desire, to study rich flames and their possible products first. Often the water to methane mole fraction ratio was 0.7 to 0.3. But mixtures down to a methane mole fraction of 0.1 were also used. It was possible, however, to inject oxygen and methane simultaneously into the supercritical water and produce a flame. Not possible was the production of true premixed flames. After a retraction of the thin inner nozzle capillary of the burner (see Fig. 1 b) the two gases could be mixed just below the reaction cell, but the flame reaction proceeded from the nozzle tip in the cell back towards this mixing point immediately. 

The heat of decomposition, Qj, of BAMO copolymer containing different levels of N3 bond density, KN3), is shown as a function of KN3) in Fig. 5.21. BAMO prepolymer is copolymerized with THF. The N3 bond density is varied by adjusting the mass fraction ratio of BAMO prepolymer and THF. 

Fig. 27. -rich liquidus of Hg, xCd,Te(s) shown by plotting temperature versus atom fraction for various labeled values of the atom fraction ratio in the liquid, Z = xcd/(xcd + xHg). Circles are from Harman (1980), triangles from Lawley (1980), squares and diamond from Tung et al. (1982). 

There are two rather striking features—the large magnitudes of the maxima in the case of the fully N-substituted acetamides or pyrrolidones which extend from about 1 to 2 cp. for the pure amides to between 4 and 5 cp. at the maxima, and the three families of curves, according to which specific mole fraction ratios the respective maxima occur. The fully N-substituted acetamides, N,N-dimethylacetamide (DMA), N,N-diethylacetamide (DEA), N,N-di-n-propylacetamide (Dn-PA), and N,N-diisopropylacetamide (Di-PA), together with N,N-diethylformamide with... 

A more significant test is the comparison of calculated and experimental fractionation ratios with particle sizes. Crocker, Kawahara, and Freiling (2) have presented Small Boy experimental 89Sr fractionation ratios vs. particle sizes. Figure 10 is a reproduction of their plot with... 

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