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Application to Experimental Data

That the turbidities of dilute polymer solutions agree with the corresponding theoretical relationship, given by Eq. (VII-37), was shown in Figs. 47 and 48. [Pg.535]

The initial slope of the /c V8, c plot may be calculated from the parameters F2 and (V )o evaluated in the manner referred to above. This slope is given by RTA which is equal to r2( /c)o. The parameter A 2 is given according to theory by Eq. (75) or (75 ). The quantity (yVvi) i(l —0/T) =J/N occurring in these equations should be independent of the molecular weight, but the factor decreases slowly [Pg.535]

The thermodynamic behavior of the dilute polymer solution depends on three factors (1) the molecular weight, (2) the thermodynamic interaction parameters and ki, or ipi and 0, which characterize the segment-solvent interaction, and (3) the configuration, or size, of the [Pg.535]

The combination of the thermodynamic parameters —0/T) occurs in the defined quantity J (see Eq. 55), which occupies the major role in the expression, Eq. (75), for A 2. A logical first objective is the evaluation of /, therefore. But according to Eq. (75), A 2 depends also on the function hence it is necessary to evaluate This latter quantity, defined by Eq. (56), depends on the parameter jS characterizing the spatial distribution of segments. Introducing Eq. (52) for jS into Eq. (56). [Pg.536]

The quantity rg is directly proportional to ilf ( see Chap. X) hence for any linear polymer homologous series their ratio, is a con- [Pg.536]

Equation 3.35 and Equation 3.36 have been tested for all three major types of CRP process, and three examples will be used by way of illustration. [Pg.90]

The nitroxide-mediated polymerization of styrene has been studied using a wide variety of nitroxides. If the phosphate nitroxide DEPN is used. [Pg.90]

In general, steady-state kinetics are snccessful in describing the majority of the CRP reactions when a convmtional radical initiator is present in the reaction, bnt power law equations may be more appropriate when a conventional irritiator is absent. [Pg.92]

Draw stmctrrres of all possible configurational isomers resulting from the polymerization of 2-chlorobutadiene. [Pg.92]

Draw repeat unit structures for the polymers obtained from  [Pg.92]


The most convenient form of the BET equation for application to experimental data is that already given in Equation (2.13), viz... [Pg.49]

Although Equation (4) is conceptually correct, the application to experimental data should be undertaken cautiously, especially when an arbitrary baseline is drawn to extract the area under the DSC melting peak. The problems and inaccuracy of the calculated crystallinities associated with arbitrary baselines have been pointed out by Gray [36] and more recently by Mathot et al. [37,64—67]. The most accurate value requires one to obtain experimentally the variation of the heat capacity during melting (Cp(T)) [37]. However, heat flow (d(/) values can yield accurate crystallinities if the primary heat flow data are devoid of instrumental curvature. In addition, the temperature dependence of the heat of fusion of the pure crystalline phase (AHc) and pure amorphous phase (AHa) are required. For many polymers these data can be found via their heat capacity functions (ATHAS data bank [68]). The melt is then linearly extrapolated and its temperature dependence identified with that of AHa. The general expression of the variation of Cp with temperature is... [Pg.261]

One isotherm that is both easy to understand theoretically and widely applicable to experimental data is due to Langmuir and is known as the Langmuir isotherm. In Chapter 9, we see that the same function often describes the adsorption of gases at low pressures, with pressure substituted for concentration as the independent variable. We discuss the derivation of Langmuir s equation again in Chapter 9 specifically as it applies to gas adsorption. Now, however, adsorption from solution is our concern. In this section we consider only adsorption from dilute solutions. In Section 7.9c.4 adsorption over the full range of binary solution concentrations is also mentioned. [Pg.332]

The partial derivatives in eqns. (153) will be functions of the potential-dependent rate constants, kj, etc. and the mean concentrations c 0,c z, and cR. So, for application to experimental data, the results of the present section have to be combined with those of Sects. 5.1.1 or 5.1.2. The interested reader can find extensive theoretical predictions of the a.c. polarogram in ref. 131. [Pg.304]

At neutral pH values, a high variation of reactivity of o-chlorophenol with ozone is observed with small changes in pH. These /cD values were found after gas-liquid kinetic model application to experimental data. Thus, the ozonation of o-chlorophenol was found to be a pseudo first-order fast gas liquid reaction as found by Hoigne and Bader [46] in homogeneous ozonation experiments. Trends of /cD with pH for other ozone-phenol reactions are similar to that depicted in Fig. 9. [Pg.51]

The isotherm that is most easily understood theoretically and widely applicable to experimental data is, known as the Langmuir isotherm. This is also the simplest model of a nonlinear isotherm. It accounts well for the adsorption of single components on homogenous surfaces at low to moderate concentrations, or for the adsorption to isolated type-I or type-II sites [103, 110, 111]. The Langmuir adsorption isotherm equation is written ... [Pg.48]

The virial isotherm describes the adsorption of monoatomic ions such as the halides on mercury and other metals. In order to test its applicability to experimental data it is plotted in the form... [Pg.568]

Roberts, D.W. and Williams, D.L. (1982) The derivation of quantitative correlations between skin sensitisation and physico-chemical parameters for alkylating agents and their application to experimental data for sultones. f Theor. Biol, 99, 807-825. [Pg.1156]

We shall summarize below the present status of the more important aspects of this subject. This seems worth while since the papers listed above overlap each other considerably and contain more detail than is necessary for applications to experimental data. [Pg.243]

In the context of the historical development of our knowledge of the structure of the 2-norbornyl cation since Winstein and Trifan s postulate in 1949, this comparison with the 1,2-dimethyl derivative is very important for aspects provided by the theory of scientific discoveries. As discussed in our book on aromatic diazo compounds (Zollinger, 1994, Chap. 9), verifications are never definitive, in science proofs are not possible (the term proof should only be used in mathematics) falsifications, however, can be definitive. It was shown that molecular orbital calculations and their application to experimental data on the IR and NMR spectra for the 2-norbornyl cation are consistent with a symmetrical, nonclassical cationic intermediate, but not with a rapid equilibrium between two classical intermediates. The... [Pg.283]

The analysis of the kinetic data was performed on the basis of the diffusion-controlled model, using the Langmuir and the aggregation isotherm, given by Eq. (2.16) and Eqs. (2.107) -(2.111), respectively. As one can see, the agreement with the theory is not satisfactory. The models developed mainly by the Bulgarian school [33] requires extensive numerical calculations so that its application to experimental data will be possible only after the elaboration of effective computer programmes. [Pg.364]

Measurement of the active coupling constants from the COSY spectra of polypeptides have been studied by Yang era/.- -" " In the first paper,-- extensive studies of simulated spectra addressed the quality of their LQ fit implementation, while the second- is devoted to the application to experimental data. In 1995, Miiller- also combined one-dimensional and two-dimensional data. He used least mean squares (LMS) to determine the spectral parameter of a onedimensional spectrum and exploited them to reconstruct the exchange matrices of two-dimensional exchange experiments. The introduction of prior knowledge into LS calculation is discussed by Stilbs.- He focused on applications in... [Pg.173]

After a first paper in 1988, " Bretthorst paved the way for the application of Bayesian probability theory (BPT) in a series of three papers.- The first presents the connection between the theory and the case of NMR phenomena and discusses parameter estimation and detection of quadrature signals. The second " shows the ability of Bayesian methods to measure the quality of a model. The third " provides examples of applications to experimental data where decaying sinusoids are assumed. A fourth paper, produced during the following two years, discusses computer time requirements and noise, and it is shown to be important to include knowledge in the analysis," " while a fifth publication is devoted to amplitude estimations for multiplets of well-separated resonances. [Pg.182]

Fig. 8.1 (a) Electrical conductivity of polycarbonate/SWCNT composites as a function of the filler mass fraction. Different commercial applications are also noted in the graph, (b) Power-law application to experimental data for the calculation of the percolation threshold. Reprinted with permission from Ramasubramaniam et al. (2003)... [Pg.211]

As pointed out by Fujita, equation 13 can be rearranged to provide for two alternative linear plots to test its applicability to experimental data and to determine the parameters/2 and jS from slopes and intercepts ... [Pg.492]

Having in mind applications to experimental data, we are essentially concerned with discrete Fourier spectra, usually coming from a FFT routine. For such spectra it has been proposed to compute ... [Pg.23]

This data handbook provides a unique opportunity to locate a substantial amount of adsorption equilibrium data in one source. The book contains a summary of thermodynamic equations for adsorption of gases and liquids and their mixtures and their application to experimental data. The authors intention was to provide a reference for engineers and scientists interested in the application of adsorption to the separation of gas and liquid mixtures. Since single component isotherms cannot be calculated from first principles, the authors correctly argue that it is necessary to use experimental data. Hence the need for the data book. Once single component data are available it is possible to use models to predict equilibrium data for multicomponent systems. Data sources are fully referenced. [Pg.248]

In this seetion, we intend to present some simple and straightforward aspects of adsorption of nonelectrolytes from binary liquid solutions on to mineral surfaces. Owing to the vast literature on this subject, we limit the presentation to a description of some frequently observed adsorption isotherms applicable to experimental data represented by the adsorption of polar molecules on to mineral oxide surfaces from dilute nonaqueous solutions. [Pg.305]

Emri, I., Tschoegl, N. W. Generating line spectra from experimental responses. Part IV Application to experimental data. RheoL Acta (1994) 33, pp. 60-70... [Pg.129]

Which of the three pictures is valid in any particular situation In most systems, in most phenomena, the manifestations of the three interaction modes would be almost equivalent, and it is then really hard for an experiment to reveal the underlying mechanism of ionic action. This is however a crucial piece of information. The literature is full of obscure ion-specific phenomena in systems that are not transparent enough to allow deeper understanding of mechanisms.Simple, good model systems are needed that would allow a clear discrimination of the modes of ionic action. Measurements are needed that allow the juxtaposition of models with experiments. Experimental observations not immediately amenable to theoretical treatment are not useful in the quest for understanding specific ion effects. On the other hand, abstract theory not capable of direct application to experimental data is also not particularly useful. [Pg.57]


See other pages where Application to Experimental Data is mentioned: [Pg.534]    [Pg.32]    [Pg.227]    [Pg.252]    [Pg.25]    [Pg.434]    [Pg.568]    [Pg.40]    [Pg.90]    [Pg.323]    [Pg.661]    [Pg.157]    [Pg.422]    [Pg.131]    [Pg.151]    [Pg.179]   


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Application of the BET equation to experimental data

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