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The aims of Chapter

In this chapter, we outline some concepts fundamental to an understanding of inorganic chemistry. We have assumed that readers are to some extent familiar with most of these concepts and our aim is to give a point of reference for review purposes. [Pg.1]


Addressing large molecular systems is the aim of Chapter 3, which reviews a recently developed model based on the combined use of quantum mechanics and molecular mechanics (QM/MM). This approach uses a fully self-consistent polarizable embedding (PE) scheme described in the paper. The PE model is generally compatible with any quantum chemical method, but this review is focused on its combination with density functional theory (DFT) and time-dependent density functional theory (TD-DFT). The PE method is based on the use of an electrostatic embedding potential resulting from the permanent charge distribution of the classically treated part of... [Pg.389]

The aim of Chapter 3 is to demonstrate the complexity of the coupling of surface rheology and bulk transport processes. It also demonstrates the close link of surface rheology and interfacial relaxation processes. [Pg.27]

The aim of Chapter 8 is to bring Chapters 5 (MF), 6 (UFJ and 7 (TTF) together and compare filtration behaviour against a number of criteria. The first criterion will be the clean membrane characteristics such as flux, permeability, operational pressure, membrane resistance, and MWCO or pore si. ... [Pg.281]

Inorganic chemistry it is not an isolated branch of chemistry The aims of Chapters 1 and 2... [Pg.1106]

The aim of Chapter 5 by Thornton et al. was to give systematic consideration to different types of transport in porous membranes. They developed a new model that allows one to predict the separation outcome for a variety of membranes in which the pore shape, size and composition are known, and conversely to predict pore characteristics with known permeation rates. [Pg.386]

The aim of Chapter 5 is to integrate in a general way the different trends in the literature and indicate where the reader can find specific details concerning the chemistry of nitrogenous extractives such as amino acids, proteins, nucleic acids, and alkaloids, and their products that occur in and beyond the lignocellulosic cell wall. Since most of the literature is covered mainly to 1983, a few key references have been added to bring selected topics up to date. The expectation is that with the further development of useful experimental systems we would be able to explain eventually why and where such compounds occur and how they can be used to our benefit. [Pg.179]

The second part of the book—Chapters 9-12— presents some selected applications of chemometrics to different topics of interest in the field of food authentication and control. Chapter 9 deals with the application of chemometric methods to the analysis of hyperspectral images, that is, of those images where a complete spectrum is recorded at each of the pixels. After a description of the peculiar characteristics of images as data, a detailed discussion on the use of exploratory data analytical tools, calibration and classification methods is presented. The aim of Chapter 10 is to present an overview of the role of chemometrics in food traceability, starting from the characterisation of soils up to the classification and authentication of the final product. The discussion is accompanied by examples taken from the different ambits where chemometrics can be used for tracing and authenticating foodstuffs. Chapter 11 introduces NMR-based metabolomics as a potentially useful tool for food quality control. After a description of the bases of the metabolomics approach, examples of its application for authentication, identification of adulterations, control of the safety of use, and processing are presented and discussed. Finally, Chapter 12 introduces the concept of interval methods in chemometrics, both for data pretreatment and data analysis. The topics... [Pg.18]

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]

In this chapter we shall first outline the basic concepts of the various mechanisms for energy redistribution, followed by a very brief overview of collisional intennoleciilar energy transfer in chemical reaction systems. The main part of this chapter deals with true intramolecular energy transfer in polyatomic molecules, which is a topic of particular current importance. Stress is placed on basic ideas and concepts. It is not the aim of this chapter to review in detail the vast literature on this topic we refer to some of the key reviews and books [U, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, and 32] and the literature cited therein. These cover a variety of aspects of tire topic and fiirther, more detailed references will be given tliroiighoiit this review. We should mention here the energy transfer processes, which are of fiindamental importance but are beyond the scope of this review, such as electronic energy transfer by mechanisms of the Forster type [33, 34] and related processes. [Pg.1046]

The aim of this section is to show how the modulus-phase formulation, which is the keytone of our chapter, leads very directly to the equation of continuity and to the Hamilton-Jacobi equation. These equations have formed the basic building blocks in Bohm s formulation of non-relativistic quantum mechanics [318]. We begin with the nonrelativistic case, for which the simplicity of the derivation has... [Pg.158]

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]

The aim of this chapter is to deal with the first task, analysis of the quality of data. Very quickly we are going to demonstrate how to get high quality data, before we move on to show how they become useful for learning. [Pg.204]

This chapter introduces the experimental work described in the following chapters. Some mechanistic aspects of the Diels-Alder reaction and Lewis-acid catalysis thereof are discussed. This chapter presents a critical survey of the literature on solvent ejfects on Diels-Alder reactions, with particular emphasis on the intriguing properties of water in connection with their effect on rate and selectivity. Similarly, the ejfects of water on Lewis acid - Lewis base interactions are discussed. Finally the aims of this thesis are outlined. [Pg.1]

The remainder of this chapter will provide the necessary background, from which the incentive of catalysing Diels-Alder reactions in water and the aims of the study will become apparent. [Pg.2]

The p sheets have the usual twist, and when two such twisted p sheets are packed together, they form a barrel-like structure (Figure 5.1). Antiparallel P structures, therefore, in general have a core of hydrophobic side chains inside the barrel provided by residues in the P strands. The surface is formed by residues from the loop regions and from the strands. The aim of this chapter is to examine a number of antiparallel p structures and demonstrate how these rather complex structures can be separated into smaller comprehensible motifs. [Pg.67]

It is the aim of this part of the chapter to show how certain predictions may be made about the solubility of a given material such as a polymer in any given solvent. We have seen that the solubility parameter has given us a measure of and Fbb but the magnitude of F b will have to be considered separately for the following systems ... [Pg.81]

The aim of this chapter is to describe the micro-mechanical processes that occur close to an interface during adhesive or cohesive failure of polymers. Emphasis will be placed on both the nature of the processes that occur and the micromechanical models that have been proposed to describe these processes. The main concern will be processes that occur at size scales ranging from nanometres (molecular dimensions) to a few micrometres. Failure is most commonly controlled by mechanical process that occur within this size range as it is these small scale processes that apply stress on the chain and cause the chain scission or pull-out that is often the basic process of fracture. The situation for elastomeric adhesives on substrates such as skin, glassy polymers or steel is different and will not be considered here but is described in a chapter on tack . Multiphase materials, such as rubber-toughened or semi-crystalline polymers, will not be considered much here as they show a whole range of different micro-mechanical processes initiated by the modulus mismatch between the phases. [Pg.221]

Complementing these very well established approaches for the study of any scientific field, namely experiments and analytical theory, very recently, computer simulations have become a powerful tool for the study of a great variety of processes occurring in nature in general [4-6], as well as surface chemical reactions in particular [7]. Within this context, the aim of this chapter is not only to offer a critical overview of recent progress in the area of computer simulations of surface reaction processes, but also to provide an outlook of promising trends in most of the treated topics. [Pg.388]

According to the aim of the present chapter, let us focus our attention on the academic-theoretical approach. It should be mentioned that in the study of surface reaction processes one frequently has to deal with fairly complex systems. Since the handling of such systems imposes severe problems, the standard procedure is to rationalize their study. The academic approach starts from simplified systems and a reduced number of plausible assumptions, and the goal is to achieve a general solution. The knowledge and understanding of these solutions allows us to undertake specific topics and more complex problems. [Pg.390]

Most of the enzymes mediating the reactions of the Calvin cycle also participate in either glycolysis (Chapter 19) or the pentose phosphate pathway (Chapter 23). The aim of the Calvin scheme is to account for hexose formation from 3-phosphoglycerate. In the course of this metabolic sequence, the NADPH and ATP produced in the light reactions are consumed, as indicated earlier in Equation (22.3). [Pg.733]

Potential functions such as MM+ discussed in Chapter 1 are fine for intramolecular interactions. MD was developed long before such sophisticated force fields became available, and in any case the aims of MM and MD simulations tend to be quite different. MM studies tend to be concerned with the identification of equihbrium geometries of individual molecules whilst MD calculations tend to be concerned with the simulation of bulk properties. Inspection of Figure 2.2 suggests that the intramolecular details ought to be less important than the intermolecular ones, and early MD studies concentrated on the intermolecular potential rather than the intramolecular one. [Pg.66]

In Chapter 3, we studied the topic of population analysis. In population analysis, we attempt a rough-and-ready numerical division of the electron density into atom and bond regions. In Mulliken theory, the bond contributions are divided up equally between the contributing atoms, giving the net charges. The aim of the present section is to answer the questions Are there atoms in Molecules , and if so, How can they be defined . According to Bader and coworkers (Bader, 1990) the answers to both questions are affirmative, and the boundaries of these atoms are determined by a particular property of the electron density. [Pg.316]

The aim of this chapter is to give a state-of-the-art report on the plastic solar cells based on conjugated polymers. Results from other organic solar cells like pristine fullerene cells [7, 8], dye-sensitized liquid electrolyte [9], or solid state polymer electrolyte cells [10], pure dye cells [11, 12], or small molecule cells [13], mostly based on heterojunctions between phthaocyanines and perylenes [14], will not be discussed. Extensive literature exists on the fabrication of solar cells based on small molecular dyes with donor-acceptor systems (see for example [2, 3] and references therein). [Pg.271]

It is the aim of this chapter to describe the nature, selectivity, and efficiency of initiation. Section 3.2 summarizes the various reactions associated with initiation and defines the terminology used in describing the process. Section 3.3 details the types of initiators, indicating the radicals generated, the byproducts formed (initiator efficiency), and any side reactions (e.g. transfer to initiator). Emphasis is placed on those initiators that see widespread usage. Section 3.4 examines the properties and reactions of the radicals generated, paying particular attention to the specificity of their interaction with monomers and other components of a polymerization system. Section 3.5 describes some of the techniques used in the study of initiation. [Pg.50]

The aim of this chapter is to introduce analytical methods that can be suitably used to overcome most LAB/LAS analytical problems. A particular value was put on newest analytical methods, which can detect byproducts in trace quantities. [Pg.89]

Although the aim of this chapter is specifically to survey the use of thioglycosides in glycosylation reactions, the presentation is incomplete without some information concerning glycosyl sulfoxides and selenoglycosides in glycosylation... [Pg.198]

Chapter 1 examined the aims of regulation and identified the basic regulations currently in existence. This chapter looks at the broad strategies that are employed to achieve these goals, and the agencies that participate in leading industry towards these goals. [Pg.21]


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AIM

The Aim

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