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Assumption mathematical

Gas-solid chromatography is best described by this theory. Here one finds diffuse front and rear boundaries with definite tailing of the rear boundary. Mathematical descriptions of systems of this type can become very complex however, with proper assumptions mathematical treatments do fairly represent the experimental data. The bands (zones) are similar to those shown in Figures 1.16 and 1.17. [Pg.15]

This highly successful qualitative model parallels the most convenient quantum mechanical approach to molecular orbitals the method of linear combination of atomic orbitals (LCAO). We have assumed that the shapes and dispositions of bond orbitals are related, in a simple way to the shapes and dispositions of atomic orbitals. The LCAO method makes the same assumption mathematically to... [Pg.927]

The next vital assumption, based on experimental observation, is the equivalence of inertial and gravitational mass. This means that a gravitational field must distort the Euclidean geometry of space and that the matter content of space must be in balance with the non-Euclidean geometry of space, known as its curvature. The field equations of general relativity summarize these assumptions mathematically. [Pg.12]

Year Investigator Objective Key assumption Mathematical approach Kinematics Time Diamond features Temperature Pad properties... [Pg.341]

Analysis for the multiple Brayton systems was built upon the foundations set by the given assumptions. Mathematical models for conditions of the Brayton and valves were determined and used to develop models including the HRS that calculate the reliability of success for a given system configuration. The mathematical models for reliability values for the combination of Brayton assembly(tes), valves and HRS can be found in Section 7.10. Results are discussed in Section 7.5. [Pg.228]

Once the production potential of the producing wells is insufficient to maintain the plateau rate, the decline periodbegins. For an individual well in depletion drive, this commences as soon as production starts, and a plateau for the field can only be maintained by drilling more wells. Well performance during the decline period can be estimated by decline curve analysis which assumes that the decline can be described by a mathematical formula. Examples of this would be to assume an exponential decline with 10% decline per annum, or a straight line relationship between the cumulative oil production and the logarithm of the water cut. These assumptions become more robust when based on a fit to measured production data. [Pg.209]

We will use the superscript a to denote surface quantities calculated on the preceding assumption that the bulk phases continue unchanged to an assumed mathematical dividing surface. For an arbitrary set of variations from equilibrium. [Pg.58]

The microscopic contour of a meniscus or a drop is a matter that presents some mathematical problems even with the simplifying assumption of a uniform, rigid solid. Since bulk liquid is present, the system must be in equilibrium with the local vapor pressure so that an equilibrium adsorbed film must also be present. The likely picture for the case of a nonwetting drop on a flat surface is... [Pg.378]

Phase factors of this type are employed, for example, by the Baer group [25,26]. While Eq. (34) is strictly applicable only in the immediate vicinity of the conical intersection, the continuity of the non-adiabatic coupling, discussed in Section HI, suggests that the integrated value of (x Vq x+) is independent of the size or shape of the encircling loop, provided that no other conical intersection is encountered. The mathematical assumption is that there exists some phase function, vl/(2), such that... [Pg.13]

Thus, the time-dependent BO model describes the adiabatic limit of QCMD. If QCMD is a valid approximation of full QD for sufficiently small e, the BO model has to be the adiabatic limit of QD itself. Exactly this question has been addressed in different mathematical approaches, [8], [13], and [18]. We will follow Hagedorn [13] whose results are based on the product state assumption Eq. (2) for the initial state with a special choice concerning the dependence of 4> on e ... [Pg.387]

Attempts have been made to devise mathematical functions to represent the distributions that are found experimentally. The mathematical treatment is necessarily based on the assumption that the number of particles in the sample is large enough for statistical considerations to be applicable. With the SOO-member sample of the previous section one could not expect any more than approximate agreement between mathematical prediction and experiment. [Pg.27]

Use of random flight statistics to derive rg for the coil assumes the individual segments exclude no volume from one another. While physically unrealistic, this assumption makes the derivation mathematically manageable. Neglecting this volume exclusion means that coil dimensions are underestimated by the random fight model, but this effect can be offset by applying the result to a solvent in which polymer-polymer contacts are somewhat favored over polymer-solvent contacts. [Pg.560]

D. R. Cox, P/anning of Experiments,]ohxi Wiley Sons, Inc., New York, 1958. This book provides a simple survey of the principles of experimental design and of some of the most usehil experimental schemes. It tries "as far as possible, to avoid statistical and mathematical technicalities and to concentrate on a treatment that will be intuitively acceptable to the experimental worker, for whom the book is primarily intended." As a result, the book emphasizes basic concepts rather than calculations or technical details. Chapters are devoted to such topics as "Some key assumptions," "Randomization," and "Choice of units, treatments, and observations."... [Pg.524]

Most of the assumptions are based on idealized models, indicating the limitations of the mathematical methods employed and the quantity and type of experimental data available. For example, the details of the combinatorial entropy of a binary mixture may be well understood, but modeling requires, in large measure, uniformity so the statistical relationships can be determined. This uniformity is manifested in mixing rules and a minimum number of adjustable parameters so as to avoid problems related to the mathematics, eg, local minima and multiple solutions. [Pg.252]

The basic underlying assumption for the mathematical derivation of chi square is that a random sample was selected from a normal distribution with variance G. When the population is not normal but skewed, square probabihties could be substantially in error. [Pg.493]

C, is the concentration of impurity or minor component in the solid phase, and Cf is the impurity concentration in the hquid phase. The distribution coefficient generally varies with composition. The value of k is greater than I when the solute raises the melting point and less than I when the melting point is depressed. In the regions near pure A or B the hquidus and solidus hues become linear i.e., the distribution coefficient becomes constant. This is the basis for the common assumption of constant k in many mathematical treatments of fractional solidification in which ultrapure materials are obtained. [Pg.1989]

The introduction of Lagrangian coordinates in the previous section allows a more natural treatment of a continuous flow in one dimension. The derivation of the jump conditions in Section 2.2 made use of a mathematical discontinuity as a simplifying assumption. While this simplification is very useful for many applications, shock waves in reality are not idealized mathematical... [Pg.26]

The theory is initially presented in the context of small deformations in Section 5.2. A set of internal state variables are introduced as primitive quantities, collectively represented by the symbol k. Qualitative concepts of inelastic deformation are rendered into precise mathematical statements regarding an elastic range bounded by an elastic limit surface, a stress-strain relation, and an evolution equation for the internal state variables. While these qualitative ideas lead in a natural way to the formulation of an elastic limit surface in strain space, an elastic limit surface in stress space arises as a consequence. An assumption that the external work done in small closed cycles of deformation should be nonnegative leads to the existence of an elastic potential and a normality condition. [Pg.118]

If we accept the assumption that the elastic wave can be treated to good aproximation as a mathematical discontinuity, then the stress decay at the elastic wave front is given by (A. 15) and (A. 16) in terms of the material-dependent and amplitude-dependent wave speeds c, (the isentropic longitudinal elastic sound speed), U (the finite-amplitude elastic shock velocity), and Cfi [(A.9)]. In general, all three wave velocities are different. We know, for example, that... [Pg.262]

Actually, our assumption about the way in which the plate material relaxes is obviously rather crude, and a rigorous mathematical solution of the elastic stresses and strains around the crack indicates that our estimate of 81i is too low by exactly a factor of 2. Thus, correctly, we have... [Pg.134]

We can see that the prior and posterior distributions have the same mathematical forms, as is required of conjugate functions. Also, we have an analytical form for the posterior, which is exact under the assumptions made in the model. [Pg.323]

Using the conservation and balance equations for the active centers, but without the assumption of a rate-limiting step, the mathematically rigorous rate expression is the UCKRON-1 Test Problem given below. [Pg.225]

Remarks The aim here was not the description of the mechanism of the real methanol synthesis, where CO2 may have a significant role. Here we created the simplest mechanistic scheme requiring only that it should represent the known laws of thermodynamics, kinetics in general, and mathematics in exact form without approximations. This was done for the purpose of testing our own skills in kinetic modeling and reactor design on an exact mathematical description of a reaction rate that does not even invoke the rate-limiting step assumption. [Pg.225]

Many of the better known shortcut equipment design methods have been derived by informed assumptions and mathematical analysis. Testing in the laboratory or field was classically used to validate these methods but computers now help by providing easy access to rigorous design calculations. [Pg.400]

The second law of thermodynamics was actually postulated by Carnot prior to the development of the first law. The original statements made concerning the second law were negative—they said what would not happen. The second law states that heat will not flow, in itself, from cold to hot. While no mathematical relationships come directly from the second law, a set of equations can be developed by adding a few assumptions for use in compressor analysis. For a reversible process, entropy, s, can be defined in differential form as... [Pg.29]

The manufacturer will have carried out a full mathematical investigation into the system vibration response. One quality control requirement will be to establish whether the correct assumptions have been made Rotor assembly and component weights should be obtained during man ufacture and verified against mathematical data used. [Pg.412]

The theory of molecular interactions can become extremely involved and the mathematical manipulations very unwieldy. To facilitate the discussion, certain simplifying assumptions will be made. These assumptions will be inexact and the expressions given for both dispersive and polar forces will not be precise. However, they will be reasonably accurate and sufficiently so, to reveal those variables that control the different types of interaction. At a first approximation, the interaction energy, (Ud), involved with dispersive forces has been calculated to be... [Pg.64]


See other pages where Assumption mathematical is mentioned: [Pg.26]    [Pg.134]    [Pg.26]    [Pg.134]    [Pg.425]    [Pg.2810]    [Pg.383]    [Pg.389]    [Pg.8]    [Pg.175]    [Pg.152]    [Pg.166]    [Pg.153]    [Pg.87]    [Pg.409]    [Pg.520]    [Pg.232]    [Pg.252]    [Pg.532]    [Pg.1035]    [Pg.1290]    [Pg.35]    [Pg.426]   
See also in sourсe #XX -- [ Pg.157 , Pg.171 ]




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