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Natural extension

The quantum phase factor is the exponential of an imaginary quantity (i times the phase), which multiplies into a wave function. Historically, a natural extension of this was proposed in the fonn of a gauge transformation, which both multiplies into and admixes different components of a multicomponent wave function [103]. The resulting gauge theories have become an essential tool of quantum field theories and provide (as already noted in the discussion of the YM field) the modem rationale of basic forces between elementary particles [67-70]. It has already been noted that gauge theories have also made notable impact on molecular properties, especially under conditions that the electronic... [Pg.100]

Inspired by the many hydrolytically-active metallo enzymes encountered in nature, extensive studies have been performed on so-called metallo micelles. These investigations usually focus on mixed micelles of a common surfactant together with a special chelating surfactant that exhibits a high affinity for transition-metal ions. These aggregates can have remarkable catalytic effects on the hydrolysis of activated carboxylic acid esters, phosphate esters and amides. In these reactions the exact role of the metal ion is not clear and may vary from one system to another. However, there are strong indications that the major function of the metal ion is the coordination of hydroxide anion in the Stem region of the micelle where it is in the proximity of the micelle-bound substrate. The first report of catalysis of a hydrolysis reaction by me tall omi cell es stems from 1978. In the years that... [Pg.138]

The material in this text assumes familiarity with topics covered in the courses and laboratory work you have already completed. This chapter provides a review of equilibrium chemistry. Much of the material in this chapter should be familiar to you, but other ideas are natural extensions of familiar topics. [Pg.135]

The chemical shift is related to the part of the electron density contributed by the valence electrons, ft is a natural extension, therefore, to try to relate changes of chemical shift due to neighbouring atoms to the electronegativities of those atoms. A good illustration of this is provided by the X-ray photoelectron carbon Is spectmm of ethyltrifluoroacetate, CF3COOCH2CH3, in Figure 8.14, obtained with AlXa ionizing radiation which was narrowed with a monochromator. [Pg.310]

A key success factor for reducing the costs and lead times for vehicle manufacturers, for example, is the degree of integration of the suppliers within the product development process. This is seen as a natural extension to concurrent engineering principles (Wyatt et al., 1998). For many years, in engineering companies, a substantial proportion of the finished product, typically two thirds, consists of components or subassemblies produced by suppliers (Noori and Radford, 1995). [Pg.271]

A natural extension of the studies in Sec. VIIA would be the investigation of the drift of a polymer chain in random environment when a constant external field B is applied in one direction [21,22]. [Pg.605]

Multithreshold rules are natural extensions of the (binary-valued) generalized threshold rule defined in equation 5.121. Using fc-state variables a G 0,1,..., A - 1 and using the j entry of the A threshold vector to define the j threshold at that site (= bij), the generalized multithreshold rule is defined as follows ... [Pg.284]

Following studies on the rearrangement of allylic arenesulfinates, Braverman and coworkers have investigated a number of natural extensions of this unique transformation, including the predictable [2,3] sigma tropic rearrangements of allylic sulfenates to sulfoxides and of propargylic sulfenates and sulfinates to allenic sulfoxides and sulfones respectively. The last reaction is described below, while the other two are described in Chapter 14. [Pg.676]

The derivation of process models for adaptive control falls exactly within the framework of the estimation problem studied in this chapter. Control-related implementation are natural extensions to the current work and are... [Pg.200]

A natural extension of column chromatography is high-pressure liquid chromatography, which combines separation, detection, and quantitation (and isolation in the case of preparatory work). Perhaps the single... [Pg.341]

A natural extension of these studies would be to identify the pools of proteins in cells and plasma that are nitrosylated (the nitrosylome) via proteomics. Although some advances have been made in this direction with the biotin switch method, where the S-NO is switched to a biotin label (Jaffrey et al, 2001) the technique is plagued by low sensitivity. The identification of the nitrosylome with techniques that allow temporal resolution shorter than signaling frequencies, under physiological and pathological conditions, will be the key to elucidation of the nitrosylation pathway. [Pg.102]

Once you realize that attributes do not directly represent stored information, the unconventional concept of a parameterized attribute is a natural extension. A parameterized attribute is one that has a defined value for each of many different possible values of its parameter(s). Like attributes generally, it is best thought of as a query, or read-only, function that has been hypothesized for some purpose it need not be directly implemented. [Pg.85]

By a natural extension of the concepts developed in the previous chapter (structural estimability), if the generic rank of the composite matrix (Aj A2) is not less than n (n number of unmeasured variables), then the system does not include structural singularities. Furthermore, if all the unmeasured nodes are determinable, then there are no isolated variables, which cannot be computed from the balance equations. [Pg.50]

To get rid of the drawbacks associated with the molten wax technique, an alternative is to solidify the droplets of the liquid of interest as soon as they are formed after leaving the nozzle. This is the basic concept of thejrozen-drop technique, a natural extension of the molten wax technique. The freeze-up and collection of droplets may be carried out in many different ways. For example, liquid droplets from a fuel spray can be collected into a stream of fluid at... [Pg.405]

A natural extension of analytical automation is some means of data processing all the results that are generated. This usually takes the form of a central computer which accepts information from different analysers for presentation in a useful manner. The identification of a sample and the tests performed are typed in using a keyboard and the computer collates all the data on each sample. As well as collecting information, computing and statistically assessing results, an important facility of the computer lies in its ability to store information for future recall via a visual display unit. [Pg.212]

In the transportation industry, there is an ever increasing use in auto, truck and bus applications. The advent of the electric vehicle, which may demand vastly improved weight reduction over today s state-of-the-art vehicles, would be a natural extension of current unsaturated polyester resin technologies. [Pg.712]

Production of pol3rmers through poly-substitution or poly-condensation reactions would be expected to be a natural extension of simple PTC chemistry. To a large extent this is true, but as Percec has shown. Chapter 9, the ability to use two-phase systems for these reactions has enormously extended the chemist s ability to control the structure of the polymers produced. Kellman and co-workers (Chapter 11) have also extensively studied poly-substitution displacements on perfluorobenzene substrate to produce unique polymers. [Pg.5]

The streetcar suburbs of the following decades offered more land, at lower prices, to a new class of homeowner. This growth was not, however, a simple, inevitable, or natural extension of growing affluence. Rather, as Kenneth Jack-son notes in his comprehensive history of the suburbs, Crahgrass Frontier, it required the emergence of a class of suburban developers and real estate specialists who lobbied municipalities for services, directed the extension of transportation, and drew the new spacious property lines for construction. The central incentive of these entrepreneurs, needless to say, was to convert as much land... [Pg.29]

The natural extension of this series to the quinoline analog of AC 252,925 was then undertaken. The synthesis route used is based on the work of E. C. Taylor which employed anthranil as a precursor to a quinoline-2,3-dicarboxylic acid derivative (11). The sequence is shown in Scheme V. [Pg.42]

Nguyen and co-workers have developed a method for the alkylation of meso-epoxides by a preformed NHC AIEtj complex (Eq. 29) [117, 154], This method is a natural extension of previous work utilizing triethylaluminum and catalytic phosphines for ring opening of epoxides [155],... [Pg.132]

Thus we see that Hartree-Fock theory is identical to a canonical transformation theory retaining only one-particle operators with an optimized reference, and the canonical transformation model retaining one- and two-particle operators employed in the current work, if employed with an optimized reference, is a natural extension of Hartree-Fock theory to a two-particle theory of correlation. [Pg.362]

Ecotoxicology is a natural extension of toxicology that studies the fate and effects of toxic substances on an ecosystem. It is based on scientiflc research that employs both laboratory and held methods. Ecotoxicology requires an understanding of ecologic principles and theories pertaining to how chemicals can affect individuals, populations, communities, and ecosystems. Individuals are single entities, whereas a... [Pg.163]


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See also in sourсe #XX -- [ Pg.135 ]




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