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Mathematical methods surfaces

Using experimental design such as Surface Response Method optimises the product formulation. This method is more satisfactory and effective than other methods such as classical one-at-a-time or mathematical methods because it can study many variables simultaneously with a low number of observations, saving time and costs [6]. Hence in this research, statistical experimental design or mixture design is used in this work in order to optimise the MUF resin formulation. [Pg.713]

Many of the studies, from which our current understanding of reactions at the oxide-electrolyte interface has developed, were based on titrations of colloidal suspensions of oxides. The key to resolving questions left open by this work lies in the study of better defined oxide surfaces, the examination of a particular interface by many different experimental methods, and the development of mathematical methods for interpreting the data. [Pg.55]

Detector dead time. This is the time required for the detection and electronic handling of an ion pulse. If another ion strikes the detector surface within the time required for handling the first ion pulse, the second ion will not be detected and, hence, the observed count rate will be lower than the actual value. If this is not corrected for, inaccurate isotope ratio results will be reported. In ICP-MS, several mathematical methods should be applied for its evaluation and correction. [Pg.30]

Examples of mathematical methods include nominal range sensitivity analysis (Cullen Frey, 1999) and differential sensitivity analysis (Hwang et al., 1997 Isukapalli et al., 2000). Examples of statistical sensitivity analysis methods include sample (Pearson) and rank (Spearman) correlation analysis (Edwards, 1976), sample and rank regression analysis (Iman Conover, 1979), analysis of variance (Neter et al., 1996), classification and regression tree (Breiman et al., 1984), response surface method (Khuri Cornell, 1987), Fourier amplitude sensitivity test (FAST) (Saltelli et al., 2000), mutual information index (Jelinek, 1970) and Sobol s indices (Sobol, 1993). Examples of graphical sensitivity analysis methods include scatter plots (Kleijnen Helton, 1999) and conditional sensitivity analysis (Frey et al., 2003). Further discussion of these methods is provided in Frey Patil (2002) and Frey et al. (2003, 2004). [Pg.59]

The further development of the theory of nonuniform surfaces in the U.S.S.R. was helped by the mathematical methods of Zel dovich and Roginskil (200,201,331). A. V. Frost analyzed some work on the subject (mostly Russian) in a recent review (10) and concluded that an equation derived by him on the assumption that the reactants are adsorbed on a uniform surface and that no significant interactions take place between the adsorbed molecules, satisfactorily described many reactions on non-uniform surfaces including cracking of individual hydrocarbons and petroleum fractions, hydrogen disproportionation, and dehydration of alcohols. From the experimental results it was concluded that the catalytic centers on the surface were not identical with the adsorption centers. The catalysts used consisted of different samples of silica-alumina and pure alumina. [Pg.222]

In the foregoing development we derived relations for the heat transfer from a rod or fin of uniform cross-sectional area protruding from a flat wall. In practical applications, fins may have varying cross-sectional areas and may be attached to circular surfaces. In either case the area must be considered as a variable in the derivation, and solution of the basic differential equation and the mathematical techniques become more tedious. We present only the results for these more complex situations. The reader is referred to Refs. 1 and 8 for details on the mathematical methods used to obtain the solutions. [Pg.46]

Thus, although the analogy between wetting phenomena in mixtures and surface-induced ordering in thin block copolymer films is not complete, the analogy does allow to extend the mathematical methods to study wetting phenomena to the present case, at least approximately. In particular, Milner and Morse [60]... [Pg.35]

Boza, A., Blanquero, R., Millan, M., and Caraballo, I. (2004), Application of a new mathematical method for the estimation of the mean surface area to calculate the percolation threshold of Lobenzarit disodium salt in controlled release matrices, Chem. Pharm. Bull., 52(7), 797-801. [Pg.1049]

Beddow [42] showed how a number of particle silhouette shapes could be analyzed and reproduced by Fourier transforms. Gotoh and Finney [52] proposed a mathematical method for expressing a single, three-dimensional body by sectioning as an equivalent ellipsoid having the same volume, surface area and projected area as the original body. [Pg.84]

J.Warren Binary Subdivision Schemes for Functions over Irregular Knot Sequences. pp543-562 in Mathematical Methods for Curves and Surfaces (eds Daehlen, Lyche and Schumaker), Vanderbilt University Press 1995 ISBN 0-8265-1268-2... [Pg.209]

N.Dyn, M.S.Floater, K.Hormann A C2 four-point subdivision scheme with fourth order accuracy and its extensions. ppl45-156 in Mathematical Methods for Curves and Surfaces, (eds Daehlen, Morken and schumaker), Nashboro Press 2005 ISBN 0-9728482-4-X... [Pg.210]

The complexity of the description increases when the admolecule holds at the surface two or more sites or when the admolecule internal configuration may change after adsorption. For simplicity these situations will not be considered Ref. [16] can be consulted for a survey of the mathematical methods required in these cases. [Pg.440]

It has been pointed out above that the Wheeler-Ono approach (see Sec. III.l) to the idealized mathematically plane surface problem is the rigorous approach, though actual numerical calculations based on the general equations are not practical. On the other hand, the Frenkel-Halsey-Hill method (see Sec. III.4) is essentially a very approximate solution of this same problem resulting in a simple and surprisingly successful isotherm equation, Eq. (38), for 0 not too small. This method can be applied to capillary condensation (see Sec. III.5) and is capable of accounting for isotherm types II to V (1,55,75). [Pg.240]

Such electrode reactions are often called reversible or nernstian, because the principal species obey thermodynamic relationships at the electrode surface. Since mass transfer plays a big role in electrochemical dynamics, we review here its three modes and begin a consideration of mathematical methods for treating them. [Pg.28]

The argument just made assumes, implicitly, a model in which the substrate is molecularly flat. Appropriate revision to account for roughness effects can be made, which will be relevant when the substrate microtopography is known. The mathematical methods that have been employed to treat the contact angle of a liquid on a rough surface (28) may be employed. For example, we may define as actual area of interface and A as actual area projected on a plane parallel to the envelope of the surface. The roughness ratio, p, is... [Pg.48]

Yu. V. Kholin, The quantitative physical-chemical analysis of complexation in solution and on the surface of chemical modified silica substantial models, mathematical methods and their applications, Kharkov, Pholio, 2000, 288 p (in Russian). [Pg.95]

In this chapter, we begin with some remarks on the technological and scientific importance of complex materials and interfaces and motivate the study of interface and surface properties. We then review some of the physical and mathematical methods that are used in the subsequent discussions of interface and membrane statistical thermodynamics. Many of these topics are discussed more fully in the references and throughout this chapter. We begin with a review of classical statistical mechanics ", including a description of fluctuations about equilibrium and of binary mixtures. The mathematical description of an interface is then presented (using only vector calculus) and the calculation of the area and curvature of an interface wifli an arbitrary shape is demonstrated. Finally, the chapter is concluded by a brief summary of hydrodynamics. ... [Pg.1]

As mentioned above, a parallel line of research has been carried out by Dzubiella, Hansen, McCammon, and Li. Early work by Dzubiella and Hansen demonstrated the importance of the self-consistent treatment of polar and nonpolar interactions in solvation models [137, 138]. These observations were then incorporated into a self-consistent variational framework for polar and nonpolar solvation behavior by Dzubiella, Swanson, and McCammon [131, 139] which shared many common elements with our earlier geometric flow approach but included an additional term to represent nonpolar energetic contributions from surface curvature. Li and co-workers then developed several mathematical methods for this variational framework based on level-set methods and related approaches [140-142] which they demonstrated and tested on a... [Pg.422]

The mathematical methods and the derivation can be found in several electrochemistry books [1 ] and reviews [5]. Herein, we present the most important considerations and formulae for steady-state electrolysis conditions. It is assumed that the solution is well stirred (the concentration gradient at the electrode surface is constant) and that both the reactant and product molecules are soluble. By combining Eqs. (1.3.28), (1.3.29), and (1.3.30) and considering the respective initial and boundary conditions [Eqs. (1.3.31), (1.3.32), and (1.3.36)], we obtain... [Pg.42]

Additional information is necessary for mapping surface-curve-surface connections. Boundary representation applies the traditional mathematical method of topology for this purpose. [Pg.59]


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Mathematical methods

Surface method

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