Rejection curve derivatives

Values of dR/dr were calculated from smoothed rejection data in Figure 1 for membranes A, B and C. b) Derivatives of theoretical rejection curves. Log-normal pore size distributions from SEM (Figure 2) and equations of the steric rejection theory (19) were used. 

The system of statistical end control, as mentioned in the previous section is called Acceptance Sampling. Elements are diverse parameters such as AQL, Producer s Risk, LQL, Consumer s Risk, the method of inspection or analytical procedure and the OC curve derived from them. Typically a plan contains not only the maximum and minimum limits of the content of product or batches but also the relative frequencies by which the outcome on content may be passed (or not) and what should be done accept or reject. 

Figure 5.68 shows the result of three calculations of this nature using the same data as that used in the estimation of nm in Fig. 5.67. The optimum value of < in this case is 0.01 1/mg corresponding to /iw of 0.4 h, Ks of lS.0mg/l and a yield coefficient of 0.5. Changing to 0.0095 or to 0.01051/mg may be seen to give distinctly curved lines which, as such, may be rejected. The values of Ks derived...

Derivation of Reaction Schemes Based on Experimental Results. Although numerous methods for evaluating reactions schemes have been developed ( 0-44), most of them (40-42) start with a hypothetical mechanism which is, by means of experiments, either confirmed or rejected. A newly developed method for the systematic elucidation of reaction schemes of complex systems requires no chemical considerations, but concentration-time measurements and system-analytical considerations (45). The method is based on the initial slope of the concentration-time profiles and when necessary the higher derivatives of these curves at t = 0. Reaction steps in which products are formed directly from reactants can be identified in a concentration-time plot by a positive gradient c. at t = 0 (zero order delay). dtJ... 

Figure 2. The derivative of transmitted current in 1,3-butadiene. The curve marked "low rejection" is obtained by rejecting only those elastically scattered electrons which return to the monochromator. The "high rejection" data is derived by rejection of all scattered electrons (from Ref. 24).

Nearly all experimental coexistence curves, whether from liquid-gas equilibrium, liquid mixtures, order-disorder in alloys, or in ferromagnetic materials, are far from parabolic, and more nearly cubic, even far below the critical temperature. This was known for fluid systems, at least to some experimentalists, more than one hundred years ago. Verschaffelt (1900), from a careful analysis of data (pressure-volume and densities) on isopentane, concluded that the best fit was with p = 0.34 and 5 = 4.26, far from the classical values. Van Laar apparently rejected this conclusion, believing that, at least very close to the critical temperature, the coexistence curve must become parabolic. Even earlier, van der Waals, who had derived a classical theory of capillarity with a surface-tension exponent of 3/2, found (1893)... 

Although the Ferry equation is based on a rather sinqile concept since it does not take into account surface effects (adsorption), flow induced deformation, hindered diffusion and other interactive and hydrodynamic effects, it may be helpful as a first estimate of the rejection of a solute in relation to the pore size of the membrane. Several investigators have shown that this simple concept can be well applied when the pore size is larger than the solute size, i.e., when X. < 1. A number of similar equations have been derived [23.24] showing about the same t) e of retention curves as obtained from eq. FV - 16. 

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