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Addition algebraic expressions

The RD model consists of sets of algebraic and differential equations, which are obtained from the mass, energy and momentum balances performed on each tray, reboiler, condenser, reflux drum and PI controller instances. Additionally, algebraic expressions are included to account for constitutive relations and to estimate physical properties of the components, plate hydraulics and column sizing. Moreover, initial values are included for each state variable. A detailed description of the mathematical model can be found in appendix A. The model is implemented in gPROMS /gOPT and solved using for the DAE a variable time step/variable order Backward Differentiation Formulae (BDF). [Pg.145]

Addition and Subtraction Only like terms can be added or sub-trac ted in two algebraic expressions. [Pg.430]

By means of this expression, the values of Yt yield [A]f, and Eq. (3-28) provides the means for data analysis. Or, with additional algebra, one can express Y, directly, and float both k] and Ye in the calculation. As an example of the application of Eq. (3-28), consider the dimer-monomer equilibration of triphenyl methyl radical 2... [Pg.51]

The effect of concentration on the rate of a particular chemical reaction can be summarized in an algebraic expression known as a rate law. A rate law links the rate of a reaction with the concentrations of the reactants through a rate constant (jt ). In addition, as we show later in this chapter, the rate law may contain concentrations of chemical species that are not part of the balanced overall reaction. [Pg.1061]

Spherical functions Y (9,(p) have comparatively simple algebraic expressions. However, we shall not present them here because actually we shall need only their orthogonality, addition and transformation properties, which will be described in Chapter 5. Let us recall that n = 1,2,3,..., / = 0,1,2,...,n— 1, mi = 0, 1, 2,..., Z, s = 1/2 and ms = 1/2. [Pg.7]

Clebsch-Gordan coefficients have already occurred several times in our considerations in the Introduction (formula (2)) while generalizing the quasispin concept for complex electronic configurations, while defining a relativistic wave function (formulas (2.15) and (2.16)), in the addition theorem of spherical functions (5.5) and in the definition of tensorial product of two tensors (5.12). Let us discuss briefly their definition and properties. There are a number of algebraic expressions for the Clebsch-Gordan coefficients [9, 11], but here we shall present only one ... [Pg.48]

The presence of the repeating terms with the same L, S causes additional difficulties while orthogonalizing the CFP, finding their phase multipliers as well as the relationships between complementary shells. Also the problem of finding the algebraic expressions for the CFP becomes much more complicated (see Chapter 16). [Pg.79]

We discussed the ABX system briefly in Section 6.13. Here we provide additional details on the form of the matrix elements, the factoring of the secular equation, and the expressions for transition frequencies and intensities. In addition, we describe in some detail the use of the resultant algebraic expressions to analyze an experimental ABX spectrum. Although such analysis for a specific case can be carried out by computer spectral simulation, it is instructive to see the steps used in the general algebraic procedure, which is analogous to that used in Section 6.8 but is more tedious. [Pg.385]

Since D/R = 6v /Me (M/N), after a little algebra, repetition of our previous analysis gives, instead of eqn (4.6), a more complicated algebraic expression involving an additional parameter s. The corresponding distribution is plotted in fig. 2 fOT e = 80 and 40, and we see that the net effect of curvature corrections is to shift N towards M and d towards Qq. Thus, with little error, we can take d = Oq, N = M, and use eqn (2.9) which becomes... [Pg.250]

This section deals with the construction of optimal higher order FDTD schemes with adjustable dispersion error. Rather than implementing the ordinary approaches, based on Taylor series expansion, the modified finite-difference operators are designed via alternative procedures that enhance the wideband capabilities of the resulting numerical techniques. First, an algorithm founded on the separate optimization of spatial and temporal derivatives is developed. Additionally, a second method is derived that reliably reflects artificial lattice inaccuracies via the necessary algebraic expressions. Utilizing the same kind of differential operators as the typical fourth-order scheme, both approaches retain their reasonable computational complexity and memory requirements. Furthermore, analysis substantiates that important error compensation... [Pg.42]

Mathematica has a powerful capability to carry out symbolic mathematics on algebraic expressions and can solve equations symbolically. In addition to the arithmetic operations, the principal Mathematica statements for manipulating algebraic expressions are Expand ], Factor ], Simplify ], Together ], and Apart ]. The Expand statement multiplies factors and powers out to give an expanded form of the expression. The following input and output illustrate this action In l] =Clear a,x]... [Pg.75]

In addition, to these binding parameters the corresponding affinity distribution can likewise be generated from the corresponding affinity distribution equation (Eq. (15)). This expression is more complex than the affinity distribution equation for the Freundlich isotherm (Eq. (8)) [26]. However, it is still a simple algebraic expression that calculates the number of binding site (Ni) having an association... [Pg.431]

To estimate the computational time required in a Gaussian elimination procedure we need to evaluate the number of arithmetic operations during the forward reduction and back substitution processes. Obviously multiplication and division take much longer time than addition and subtraction and hence the total time required for the latter operations, especially in large systems of equations, is relatively small and can be ignored. Let us consider a system of simultaneous algebraic equations, the representative calculation for forward reduction at stage is expressed as... [Pg.202]

We see that when a reaction can be expressed as the algebraic sum of a sequence of two or more other reactions, then the heat of the reaction is the algebraic sutn of the heats of these reactions. This generalization has been found to be applicable to every reaction that has been tested. Because the generalization has been so widely tested, it is called a law—the Law of Additivity of Reaction Heats. ... [Pg.111]


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Algebraic expressions

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