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Chapter Purpose

The main purpose of this chapter is to understand and discover, through examples, the importance of mathematical modeling and to start constructing simple mathematical models. The second purpose is introduce you to process and bioprocess simulation. Again, in the case of simulation, you have already been exposed to and practiced simulation through some exercises in previous chapters of the [Pg.245]

Simpson and S.K. Sastry, Chemical and Bioprocess Engineering Fundamental Concepts for First-Year Students, DOI 10.1007/978-l-4614-9126-2 9, [Pg.245]

9 Fundamentals of Mathematical Modeling, Simulation, and Process Control [Pg.246]

Finally, our main target is to continuously show you, through examples, the beauty and broad application of chemical and bioprocess engineering. [Pg.246]


Naturally, plant ingredients are not the only source of food and drinks. Actually, in advanced developed countries, food from animal source is dominating where milk and meat represent the most concrete examples of drink and food, respectively. Nevertheless, the prevalence of specific applications, such as protein components useful for human health, stimulates the development of plant consumption. As a counterpart, plants also contain threatening protein components (toxins and allergens) that require attention for an improved food security therefore, there is a need of detecting low-abundance proteins (the deep proteome) from plant tissues as schematically illustrated in Figure 1. It is within this context that this chapter purposely limits the discussion to plant proteomics. The description about the situation of low-abundance animal-derived food proteomics has been made by the same authors in various other documents (3-6). [Pg.132]

Proceeding from the said above, this chapter purpose is the solution of the considered above paramount problems with the help of modem experimental and theoretical techniques on the example of particulate-filled butadiene-styrene mbber. [Pg.80]

The present chapter purpose it the application of fractal analysis for description of polymerization kinetics in nanofiller presence. [Pg.70]

In this chapter, we will discuss petroleum products used for energy purposes, that is, motor fuels and heating fuels. Chapter 6 will be devoted to other products such as special gasolines, lubricants, petrochemical bases, and asphalts. [Pg.177]

Currently the charts used most often for this purpose are those published by the API. (Maxwell and Bonnel charts) from the Technical Data Book (see Chapter 4). [Pg.332]

The purpose of this chapter is to present a special class of compounds, additives, that plays an Important role in the formulation of fuels as well as lubricants. [Pg.345]

The particularity of each method comes in fact from the "device" object. A "device" is an element of a NDT equipment. The standard aims to define standard "device" objects for the considered 8 NDT methods this is the purpose of chapter 8.3. Nonetheless, the standard draft intends to be open to new teclmiques or to the evolution of conventional techniques, and the possibility is given to define "non-standard devices , under restrictions which are given in the document ("general rules for compliance"). [Pg.926]

The purpose of this chapter is to provide an introduction to tlie basic framework of quantum mechanics, with an emphasis on aspects that are most relevant for the study of atoms and molecules. After siumnarizing the basic principles of the subject that represent required knowledge for all students of physical chemistry, the independent-particle approximation so important in molecular quantum mechanics is introduced. A significant effort is made to describe this approach in detail and to coimnunicate how it is used as a foundation for qualitative understanding and as a basis for more accurate treatments. Following this, the basic teclmiques used in accurate calculations that go beyond the independent-particle picture (variational method and perturbation theory) are described, with some attention given to how they are actually used in practical calculations. [Pg.4]

Time-of-flight mass spectrometers have been used as detectors in a wider variety of experiments tlian any other mass spectrometer. This is especially true of spectroscopic applications, many of which are discussed in this encyclopedia. Unlike the other instruments described in this chapter, the TOP mass spectrometer is usually used for one purpose, to acquire the mass spectrum of a compound. They caimot generally be used for the kinds of ion-molecule chemistry discussed in this chapter, or structural characterization experiments such as collision-induced dissociation. Plowever, they are easily used as detectors for spectroscopic applications such as multi-photoionization (for the spectroscopy of molecular excited states) [38], zero kinetic energy electron spectroscopy [39] (ZEKE, for the precise measurement of ionization energies) and comcidence measurements (such as photoelectron-photoion coincidence spectroscopy [40] for the measurement of ion fragmentation breakdown diagrams). [Pg.1354]

Section VI shows the power of the modulus-phase formalism and is included in this chapter partly for methodological purposes. In this formalism, the equations of continuity and the Hamilton-Jacobi equations can be naturally derived in both the nonrelativistic and the relativistic (Dirac) theories of the electron. It is shown that in the four-component (spinor) theory of electrons, the two exha components in the spinor wave function will have only a minor effect on the topological phase, provided certain conditions are met (nearly nonrelativistic velocities and external fields that are not excessively large). [Pg.101]

An alternative approximation scheme, also proposed by Bom and Oppenheimer [5-7], employed the straightforward perturbation method. To tell the difference between these two different BO approximation, we call the latter the crude BOA (CBOA). A main purpose of this chapter is to study the original BO approximation, which is often referred to as the crude BO approximation and to develop this approximation into a practical method for computing potential energy suifaces of molecules. [Pg.401]

In Chapter VIII, Haas and Zilberg propose to follow the phase of the total electronic wave function as a function of the nuclear coordinates with the aim of locating conical intersections. For this purpose, they present the theoretical basis for this approach and apply it for conical intersections connecting the two lowest singlet states (Si and So). The analysis starts with the Pauli principle and is assisted by the permutational symmetry of the electronic wave function. In particular, this approach allows the selection of two coordinates along which the conical intersections are to be found. [Pg.770]

In Chapter IX, Liang et al. present an approach, termed as the crude Bom-Oppenheimer approximation, which is based on the Born-Oppen-heimer approximation but employs the straightforward perturbation method. Within their chapter they develop this approximation to become a practical method for computing potential energy surfaces. They show that to carry out different orders of perturbation, the ability to calculate the matrix elements of the derivatives of the Coulomb interaction with respect to nuclear coordinates is essential. For this purpose, they study a diatomic molecule, and by doing that demonstrate the basic skill to compute the relevant matrix elements for the Gaussian basis sets. Finally, they apply this approach to the H2 molecule and show that the calculated equilibrium position and foree constant fit reasonable well those obtained by other approaches. [Pg.771]

In Chapter XI, Peric and Peyerimhoff discuss the Renner-Teller coupling in triatomic and tetraatomic molecules. For this purpose, they describe some of their theoretical tools to investigate this subject and use the systems FeH2, CNC, and FICCS as adequate examples. [Pg.771]

Metadatabases are databases which describe other databases in a comprehensive and stnretured way [51], A prominent example is the DAIN Metadatabase of Internet Resources for Environmental Chemicals kctp //wwMmz.uni-ka el.de/dain) which in 2002 comprised more than 700 entries. This metadatabase is documented in Chapter V, Section 10 of the Handbook, on Databa.scs on Enviromnental Information", It supports the user in finding the right database(s) for their purposes. [Pg.275]

The explicit definition of water molecules seems to be the best way to represent the bulk properties of the solvent correctly. If only a thin layer of explicitly defined solvent molecules is used (due to hmited computational resources), difficulties may rise to reproduce the bulk behavior of water, especially near the border with the vacuum. Even with the definition of a full solvent environment the results depend on the model used for this purpose. In the relative simple case of TIP3P and SPC, which are widely and successfully used, the atoms of the water molecule have fixed charges and fixed relative orientation. Even without internal motions and the charge polarization ability, TIP3P reproduces the bulk properties of water quite well. For a further discussion of other available solvent models, readers are referred to Chapter VII, Section 1.3.2 of the Handbook. Unfortunately, the more sophisticated the water models are (to reproduce the physical properties and thermodynamics of this outstanding solvent correctly), the more impractical they are for being used within molecular dynamics simulations. [Pg.366]

Thus, a list of 1 5 descriptors was calculated for these purposes, as described below. The partition coefficient log P (calculated by a method based on the Gho.sc/Crip-pen approach [11]) (see also Chapter X, Section 1.1 in the Handbook) was calculated because it affects the solubility dramatically [17, 18]. All the other descriptors were calculated with the program PETRA (Parameter Estimation for the Treatment of Reactivity Applications) [28. ... [Pg.498]

The examples examined earlier in this Chapter and those given in the Exereises and Problems serve as useful models for ehemieally important phenomena eleetronie motion in polyenes, in solids, and in atoms as well as vibrational and rotational motions. Their study thus far has served two purposes it allowed the reader to gain some familiarity with applieations of quantum meehanies and it introdueed models that play eentral roles in mueh of ehemistry. Their study now is designed to illustrate how the above seven rules of quantum meehanies relate to experimental reality. [Pg.52]

The aromatic shifts that are induced by 5.1c, 5.If and S.lg on the H-NMR spectrum of SDS, CTAB and Zn(DS)2 have been determined. Zn(DS)2 is used as a model system for Cu(DS)2, which is paramagnetic. The cjkcs and counterion binding for Cu(DS)2 and Zn(DS)2 are similar and it has been demonstrated in Chapter 2 that Zn(II) ions are also capable of coordinating to 5.1, albeit somewhat less efficiently than copper ions. Figure 5.7 shows the results of the shift measurements. For comparison purposes also the data for chalcone (5.4) have been added. This compound has almost no tendency to coordinate to transition-metal ions in aqueous solutions. From Figure 5.7 a number of conclusions can be drawn. (1) The shifts induced by 5.1c on the NMR signals of SDS and CTAB... [Pg.145]

First of all, given the well recognised promoting effects of Lewis-acids and of aqueous solvents on Diels-Alder reactions, we wanted to know if these two effects could be combined. If this would be possible, dramatic improvements of rate and endo-exo selectivity were envisaged Studies on the Diels-Alder reaction of a dienophile, specifically designed for this purpose are described in Chapter 2. It is demonstrated that Lewis-acid catalysis in an aqueous medium is indeed feasible and, as anticipated, can result in impressive enhancements of both rate and endo-exo selectivity. However, the influences of the Lewis-acid catalyst and the aqueous medium are not fully additive. It seems as if water diminishes the catalytic potential of Lewis acids just as coordination of a Lewis acid diminishes the beneficial effects of water. Still, overall, the rate of the catalysed reaction... [Pg.161]

Once a PES has been computed, it is often fitted to an analytic function. This is done because there are many ways to analyze analytic functions that require much less computation time than working directly with ah initio calculations. For example, the reaction can be modeled as a molecular dynamics simulation showing the vibrational motion and reaction trajectories as described in Chapter 19. Another technique is to fit ah initio results to a semiempirical model designed for the purpose of describing PES s. [Pg.176]

It is the purpose of this chapter to provide a resume of theoretical concepts which are used in discussing aromatic reactivity. Extended discussion is imnecessary, for many of the concepts are the common currency of organic chemistry, and have been frequently expounded. - ... [Pg.122]

It is the purpose of this and the following chapter to report the quantitative data concerning the relationship of structure to orientation and reactivity in aromatic nitration. Where data obtained by modern analytical methods are available they are usually quoted in preference to the results of older work. Many of the papers containing the latter are, however, noted in the brief discussion which is given of interpretations of the results. [Pg.163]

Periodic acid cleavage of vicinal diols is often used for analytical purposes as an aid m structure determination By identifying the carbonyl compounds produced the con stitution of the starting diol may be deduced This technique finds its widest application with carbohydrates and will be discussed more fully in Chapter 25... [Pg.648]

New Chapter 1 has been retitled Structure Deter mines Properties to better reflect its purpose and has been rewritten to feature a detailed treatment of acids and bases Rather than a review of what stu dents learned about acids and bases m general chemistry Sections 1 12-1 17 discuss acids and bases from an organic chemistry perspective... [Pg.1331]

The f-curve and its associated t-plot were originally devised as a means of allowing for the thickness of the adsorbed layer on the walls of the pores when calculating pore size distribution from the (Type IV) isotherm (Chapter 3). For the purpose of testing for conformity to the standard isotherm, however, a knowledge of the numerical thickness is irrelevant since the object is merely to compare the shape of the isotherm under test with that of the standard isotherm, it is not necessary to involve the number of molecular layers n/fi or even the monolayer capacity itself. [Pg.98]


See other pages where Chapter Purpose is mentioned: [Pg.9]    [Pg.137]    [Pg.213]    [Pg.245]    [Pg.277]    [Pg.325]    [Pg.9]    [Pg.137]    [Pg.213]    [Pg.245]    [Pg.277]    [Pg.325]    [Pg.802]    [Pg.883]    [Pg.97]    [Pg.329]    [Pg.177]    [Pg.506]    [Pg.89]    [Pg.1101]    [Pg.175]    [Pg.284]    [Pg.24]    [Pg.47]   


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Chapter Purpose and Strategy

Purpose of the Chapter

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