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Unifying model, simple

The simple models that we have reviewed here help in visualizing the strueture of liquid-liquid interfaces and the reaetions that oeeur at them. In addition, they prediet trends and orders of magnitudes. So far, the lattice gas has been unique in that it ean serve as a unifying model for praetieally all processes at the interfaee. The other models that we have discussed aim to explain partieular features. [Pg.187]

The most fruitful approach steers the middle course of establishing simple theoretical models of the complex in terms of suitable transferable parameters which may be calculated, or determined empirically by some other technique which is, in itself independent of the chirality of the complex. The empirical rules may then be assessed theoretically, and the range of their validity defined explicitly in terms of such parameters. The critical discussion of such a simple, unified model in terms of transferable, well-defined parameters is the main aim of this paper. [Pg.73]

A simple unified model based on the concepts of universality and scaling for the shear viscosity of dispersions of solid particles in both non-Newtonian and Newtonian fluids was developed. This model was presented in the very broad context of a review article listing more than 200 references [42]. Highlights from this work are summarized below. [Pg.569]

The observation of viscous flow in SiOz films was first reported by EerNisse(23,24). Essentially, a compressive intrinsic stress was found to exist in Si02 films grown below 1000°C and this stress was relieved at higher temperatures. The densification of SiO films was reported(20,21) and a unified model that explains both the occurrence of stress in Si0 and the higher density was published(25). This model utilized the concept of viscous relaxation in a Maxwell solid. The main idea is depicted in Fig.7 where the molar volume change is seen to cause the stress and density increase which are both relieved via viscous flow at sufficiently high temperatures. These ideas were recently incorporated into a revised oxidation mode1(26). Part of this revision modifies the oxidation expression to include the stress driven viscous relaxation. From a consideration of SiC as a simple Maxwell solid the expression for F becomes ... [Pg.43]

An important consequence of this unified model approach is that it can be applied to all reactor configurations, since it is based on common principles for the dynamic interaction of kinetics and transports. These results demonstrate that simple loading criteria cannot predict the performance of a variety of biofilm operations because they ignore the interactions among and reactor balance. [Pg.365]

Figure 11.22 A simple unified model for free energy change of a chemical reaction in solution. Each parabola is a function of the solvent displacement coordinate rand the solute reaction coordinate q. The minimal energy path followed by the system, as shown, involves both coordinates, just as in the toy model of Section 11.2.2.1. Here we do not couple the two motions, although we could. To apply transition state theory we need to know where is the lowest energy barrier and what is its height. Figure 11.22 A simple unified model for free energy change of a chemical reaction in solution. Each parabola is a function of the solvent displacement coordinate rand the solute reaction coordinate q. The minimal energy path followed by the system, as shown, involves both coordinates, just as in the toy model of Section 11.2.2.1. Here we do not couple the two motions, although we could. To apply transition state theory we need to know where is the lowest energy barrier and what is its height.
One possibility for this was demonstrated in Chapter 3. If impact theory is still valid in a moderately dense fluid where non-model stochastic perturbation theory has been already found applicable, then evidently the continuation of the theory to liquid densities is justified. This simplest opportunity of unified description of nitrogen isotropic Q-branch from rarefied gas to liquid is validated due to the small enough frequency scale of rotation-vibration interaction. The frequency scales corresponding to IR and anisotropic Raman spectra are much larger. So the common applicability region for perturbation and impact theories hardly exists. The analysis of numerous experimental data proves that in simple (non-associated) systems there are three different scenarios of linear rotator spectral transformation. The IR spectrum in rarefied gas is a P-R doublet with either resolved or unresolved rotational structure. In the process of condensation the following may happen. [Pg.224]

This author is perfectly aware that he could add very little to the work done by these workers if an attempt was made to focus on intramolecular catalysis phenomena or on the relevance to cyclisation of available models of chain conformation and chain dynamics instead, the aim will be the presentation of a general treatment of the subject, namely, one that includes the cyclisation of very short chains as well as that of very long chains of, say, 100 atoms or more. With a subject as vast as this, an encyclopaedic review would be a hopeless task. Therefore, the subject will be treated in a systematic and critical way, with more concentration on reaction series with regular and wide variations in structure, rather than on scattered examples. The aim will be to show that the field of intramolecular reactions is a mature area in which the merging of concepts from both physical organic chemistry and polymer chemistry leads to a unified treatment of cyclisation rates and equilibria in terms of a few simple generalisations and theories. [Pg.3]

Since the above simple derivation unifies the TF model and the vW model in a coherent approach, researchers were quite encomaged to try other extensions based on Eq. (53) to improve its accuracyThere are two simple ways to accomplish this replacing G [g] by a function of electron number N and nuclear charge... [Pg.132]

W. H. Miller For a reaction such as H + O2 — OH + O, or ketene isomerization CC O — OCC H2, which involve a metastable intermediate, one can certainly do better than simple TST by using a model with two transition states and the unified statistical model to approximate the net reactive flux. Such an approach, though often useful, is nevertheless an approximate model that can never be made into a rigorous description. Such a model, for example, cannot describe the resonance tunneling structure in the ketene isomerization that I described. [Pg.869]

The purpose of the present study is to show a unified picture for understanding the electronic properties of A Qo based on a simple model. In this model, both the electron-electron interaction U and the electron-phonon interaction S are taken... [Pg.538]

Introduction of XML formats was a very important step toward better intercomputer communication, but it is not a miraculous solution to all problems. Not every possible relation is easily expressed in XML (Wang et al. 2005), so specifications usually contain many implicit assumptions that are not properly formalized. The Resource Description Framework (RDF) provides a very powerful yet simple model for this formalization (Manola and Miller 2004). In this framework, any information is transformed to basic units called triplets that are combined to map the available information. This unifying mechanism can be used to express hierarchical vocabularies for domain knowledge description, as in RDF Schema (Brickley and Guha 2004) or its extension, Web Ontology Language (OWL) (Smith et al. 2004), both standardized by the W3C. [Pg.116]


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