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Subject algebraic expression

Another loose end is the relationship between the quasi-algebraic expressions that matrix operations are normally written in and the computations that are used to implement those relationships. The computations themselves have been covered at some length in the previous two chapters [1, 2], To relate these to the quasi-algebraic operations that matrices are subject to, let us look at those operations a bit more closely. [Pg.25]

Resistance functions have been evaluated in numerical compu-tations15831 for low Reynolds number flows past spherical particles, droplets and bubbles in cylindrical tubes. The undisturbed fluid may be at rest or subject to a pressure-driven flow. A spectral boundary element method was employed to calculate the resistance force for torque-free bodies in three cases (a) rigid solids, (b) fluid droplets with viscosity ratio of unity, and (c) bubbles with viscosity ratio of zero. A lubrication theory was developed to predict the limiting resistance of bodies near contact with the cylinder walls. Compact algebraic expressions were derived to accurately represent the numerical data over the entire range of particle positions in a tube for all particle diameters ranging from nearly zero up to almost the tube diameter. The resistance functions formulated are consistent with known analytical results and are presented in a form suitable for further studies of particle migration in cylindrical vessels. [Pg.338]

The combination of reaction kinetics and reactor design has been studied as a major subject of catalytic reaction engineering since the 1950s. Early studies used global rate expressions to determine the reaction rate. Purely empirical algebraic expressions were used to express the chemical reaction rate. If a reaction occurs on a molecular level in exactly the way it is described by the reaction equation, it is called an elementary reaction (micro-kinetic model). Otherwise, it is a global reaction, overall reaction, or net reaction (macrokinetic) (Deutschmann, 2008). [Pg.50]

Equation 22.2-22 is then numerically integrated simultaneously with solution of the algebraic equation t = t(fB) given below for each of the cases (a) to (d). The integration is from t = 0 to t = f1 subject to the initial condition that fB = 0 at f = 0. The expressions for t(fB) are taken from Table 9.1, as follows. [Pg.565]

The chemical laboratory became a locus for a quantitative chemistry. In the mid-eighteenth century, Venel had called for a new Paracelsus, who would put chemistry at the side of "la Physique calculee."73 While Lavoisier aspired to make chemistry a discipline as logically systematic as geometry,74 his success lay in introducing precise numbers into the chemical laboratory.75 Thus, Lavoisier, a close collaborator with the mathematician and experimentalist Laplace, was confident that chemistry could attain "results as certain as one can hope for in physics"76 and that in the future its subject matter could be expressed algebraically.77... [Pg.68]

This way of expressing the overall modes for the pair of molecular units is only approximate, and it assumes that intramolecular coupling exceeds in-termolecular coupling. The frequency difference between the two antisymmetric modes arising in the pair of molecules jointly will depend on both the intra- and intermolecular interaction force constants. Obviously the algebraic details are a bit complicated, but the idea of intermolecular coupling subject to the symmetry restrictions based on the symmetry of the entire unit cell is a simple and powerful one. It is this symmetry-restricted intermolecular correlation of the molecular vibrational modes which causes the correlation field splittings. [Pg.346]

The presentation of the subject matter so far has been cast in a somewhat deductive form, starting from a small number of axioms and exploring the mathematical consequences flowing therefrom or from individual minor modifications of the basic assumptions. The approach has been followed to establish the connection between very simple postulates and mathematically cumbersome-looking expressions for medium isotope effects. The procedure seems justified since it appears to us that the simple postulates are not seriously in error and will be substantially retained in any more complete theory. Possible improvements have been discussed in a mathematical vein, rather than by appealing to experimental data to point out where the basic theory is in need of modification. We hope that the reasons for this procedure have not entirely been lost in the algebra. Basically, the simple theory is fairly satisfactory. Its shortcomings are discernible only by precise... [Pg.294]

All branches of mathematics are interrelated, as may be seen from the school curriculum. Mathematics is the study of quantitative relationships. When such relationships are expressed in terms of number, that branch of mathematics is called arithmetic. When relationships are expressed in letters and numbers, with similar rules to arithmetic, the subject is known as algebra. Trigonometry studies relationships between angles. Geometry is concerned with size, shape, area, and volume of objects and position in space. [Pg.256]

The general expression in Eqn. 42 can be subjected to a further analysis, however the algebra is quite comphcated and consequently is not considered here. The reader is referred to the paper by Lyons et and by Albery and Bartlett for further details. [Pg.258]

The density matrix representation of spin and orbital angular momentum is capable of expressing a static state of matter and its time-dependent response to an external perturbation. Our application necessitates that we follow the response of the orbital and spin momenta subject to full or partial excitations, and the density matrix provides a direct solution to the stochastic Liouville equation. But the density matrix representation in a rotating operator is algebraically ambiguious, and we must also clarify the algebraic description of selective excitation of multiquantum systems. [Pg.180]

Thermodynamics is one of the few topics that one can approach from two completely different perspectives and arrive at the same answers. One approach, the phenomenological approach, is the subject of the first eight chapters of this book. It is based on the observation of phenomena, whose behaviors are generalized by various algebraic and calculus expressions. Over the course of countless of observations, some generalities have been used as summaries to describe how all known systems should behave. These summaries are known as the three laws of thermodynamics. [Pg.601]

Laplace transform, it also contains the value of Cb (0), i.e. the initial condition for solving the problem. After that, the form laplace ( Cb (t), t, s) is replaced with the variable LB and the resulting algebraic equation is solved for this variable. Next, the operator solution is subjected to the inverse Laplace transform (the operator invlaplace, s). The final expression defines the analytical form of the function Cb (t). [Pg.48]


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Algebraic expressions

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