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Logarithmic functions curve-fitting

The isosteric heats of adsorption, AH so, were calculated as a function of nitrogen loading for each of the samples tested. For each sample, the AHiS0 was found to decrease logarithmically with increased loading and this functionality is consistent with the assumptions of the Freundlich adsorption equation. As before, the brevity of presentation, the heat of adsorption data were curve fitted to an equation of the form ... [Pg.337]

The diagram in Figure 20 reflects the material consumption/time relationship with the original zinc layer. Curve applies to an increased pH and low flow rate it indicates residual layers of zinc after 10 years. At a low pH and higher flow rate, the zinc layer has been removed after about 2 years and corrosive attack starts on the steel (Curve (D). While Curves and (2) apply to an initial oxygen content of 6 to 8 mg/1, Curve (D is typical of pH 7.0 and c(02) of 0.5 mg/1. Mathematical analysis of the material consumption/time curves plotted showed a good fit on these curves when the logarithmic function... [Pg.124]

FIGURE 6.6 Schilcl regression for pirenzepine antagonism of rat tracheal responses to carbachol. (a) Dose-response curves to carbachol in the absence (open circles, n = 20) and presence of pirenzepine 300 nM (filled squares, n = 4), 1 jjM (open diamonds, n=4), 3j.lM (filled inverted triangles, n = 6), and 10j.iM (open triangles, n = 6). Data fit to functions of constant maximum and slope, (b) Schild plot for antagonism shown in panel A. Ordinates Log (DR-1) values. Abscissae logarithms of molar concentrations of pirenzepine. Dotted line shows best line linear plot. Slope = 1.1 + 0.2 95% confidence limits = 0.9 to 1.15. Solid line is the best fit line with linear slope. pKB = 6.92. Redrawn from [5],... [Pg.105]

Figure 5 The upper panel shows the logarithm of the specific volume as a function of temperature for a cooling rate T = 52.083 10-6, with error bars determined from 55 independent cooling runs. The lines are fits with a constant expansion coefficient in the melt (continuous line) and glass phase (dashed line), respectively. The lower panel shows the common fit curve for all cooling rates in the melt and fit curves in the glass for four cooling rates given in the legend. Figure 5 The upper panel shows the logarithm of the specific volume as a function of temperature for a cooling rate T = 52.083 10-6, with error bars determined from 55 independent cooling runs. The lines are fits with a constant expansion coefficient in the melt (continuous line) and glass phase (dashed line), respectively. The lower panel shows the common fit curve for all cooling rates in the melt and fit curves in the glass for four cooling rates given in the legend.
Wegscheider fitted a cubic spline function to the logarithmically transformed sample means of each level. This method obviates any lack of fit, and so it is not possible to calculate a confidence band about the fitted curve. Instead, the variance in response was estimated from the deviations of the calibration standards from their means at an Ot of 0.05. The intersection of this response interval with the fitted calibration line determined the estimated amount interval. [Pg.185]

Figure 7 Standard representation of the dependency ju(T) for these liquids. The fitting curve presents the reference-invariant function x after Pawlowski. The numerical value of the parameter of this function is —1.2 for water and —0.167 for other fiuids. Logarithmic variation is 5.25 x 10 for water and 1.51 x 10 for other fiuids. Source From Ref. 11, Chapter 8.2. Figure 7 Standard representation of the dependency ju(T) for these liquids. The fitting curve presents the reference-invariant function x after Pawlowski. The numerical value of the parameter of this function is —1.2 for water and —0.167 for other fiuids. Logarithmic variation is 5.25 x 10 for water and 1.51 x 10 for other fiuids. Source From Ref. 11, Chapter 8.2.
The nature of any degradation relationship will determine whether the data should be transformed for linear regression analysis. Usually, the relationship can be represented by a linear, quadratic, or cubic function on an arithmetic or logarithmic scale. Statistical methods should be employed to test the goodness of fit of the data from all batches and combined batches (where appropriate) to the assumed degradation line or curve. [Pg.9]

Basic Protocol 2 is for time-dependent non-Newtonian fluids. This type of test is typically only compatible with rheometers that have steady-state conditions built into the control software. This test is known as an equilibrium flow test and may be performed as a function of shear rate or shear stress. If controlled shear stress is used, the zero-shear viscosity may be seen as a clear plateau in the data. If controlled shear rate is used, this zone may not be clearly delineated. Logarithmic plots of viscosity versus shear rate are typically presented, and the Cross or Carreau-Yasuda models are used to fit the data. If a partial flow curve is generated, then subset models such as the Williamson, Sisko, or Power Law models are used (unithi.i). [Pg.1143]

An advantageous nice feature of the er-moment approach is its ability to plot the dependence of the fitted logarithmic partition property as a function of the polarity, a. In Fig. 9.4, we show the respective curves for the log Roc model in comparison with the logRow model. It is apparent that log Roc exhibits a striking similarity to log Row, but it is much more sensitive to strong polarities at both ends of the partition coefficients increase with the amount of hydrogen-bond-donor surface. [Pg.146]

In a double logarithmic plot of P(q) vs. q, the asymptotic slope at high q of the upper envelope of the scattering curve depends on the ratio of the wall membrane thickness to the outer diameter, e.g -2 for an infinitely thin shell from Eq. (2) and -4 for a solid sphere from Eq. (3). By fitting an experimental scattering curve to the theoretical functional form of Eq. (I). two parameters. [Pg.251]

Different functional expressions have been adopted to fit the available size distribution measurements and provide a base for analytic modeling. Mainly used at present are the log normal and the equivalent zeroth order logarithmic distribution (ZOLD), bell-shaped, monomodal curves characterised by a maximum and a width parameter. [Pg.269]


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