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Facilitation

Equation (1) is of little practical use unless the fuga-cities can be related to the experimentally accessible quantities X, y, T, and P, where x stands for the composition (expressed in mole fraction) of the liquid phase, y for the composition (also expressed in mole fraction) of the vapor phase, T for the absolute temperature, and P for the total pressure, assumed to be the same for both phases. The desired relationship between fugacities and experimentally accessible quantities is facilitated by two auxiliary functions which are given the symbols (f... [Pg.14]

Bucherer reaction Bucherer discovered that the interconversion of 2-naphthol and 2-naphthylamine through the action of alkali and ammonia could be facilitated if the reaction was carried out in the presence of (HSO3]" at about 150 C. This reaction is exceptional for the ease with which an aromatic C —OH bond is broken. It is not of general application, it is probable that the reaction depends upon the addition of [HSO3]" to the normally unstable keto-form of 2-naphthol, and subsequent displacement of —OH by —NH2. [Pg.69]

Nitro-compounds are prepared by the direct action of nitric acid. The reaction is greatly facilitated if a mixture of nitric and sulphuric acid is used. [Pg.277]

This technique is used to quantify one or more components in a mixture, i.e., extracting them from mixtures to facilitate their final analysis. An example is that for the asphaltenes, already described in the definition of these components in article 1,2.1. [Pg.25]

Construction of expert systems is facilitated if it is possible (at least approximately) to describe (model) expected signal from defect and non-defect pieces. If no models for the problem are available then the knowledge about the problem has to be acquired from an expert (the NDT inspector). However, the knowledge possessed by the expert is often incomplete and not well formalised, which makes knowledge acquisition a difficult task for the knowledge engineer. [Pg.100]

A number of real objects with artificially made disbonds were tested using the Fokker Bond Tester and spectra were stored in a PC for the classification. One of the objects, "Lower wing skin is shown in Figure 4. As can be seen, the positions and sizes of flaws are marked. The same marks were also drawn on the actual objects to facilitate measurements. [Pg.109]

Depending on the requirements, C-scan or a cascading display are used. These types of display facilitate tests for internal damage below the surface with low-frequency eddy currents in addition to high-frequency tests for surface cracks. [Pg.307]

The application of IP can facilitate or even make feasible some experimental techniques in NR, where the neutron source intensity poses a problem for imaging with radiographic films. [Pg.510]

This study describes one stage of a soft tool realisation, which facilitate and improve the task of the expert for x-ray image interpretation and decision-making. We are interested by tbe first four stages of this flow chart. [Pg.525]

In conclusion, segmentation reduces the huge amount of image information analysed, without loosing relevant details (defects). This work represents a preliminary decision assistance stage, that will facilitate the expert task in defect detection. [Pg.529]

The attachment of pyrene or another fluorescent marker to a phospholipid or its addition to an insoluble monolayer facilitates their study via fluorescence spectroscopy [163]. Pyrene is often chosen due to its high quantum yield and spectroscopic sensitivity to the polarity of the local environment. In addition, one of several amphiphilic quenching molecules allows measurement of the pyrene lateral diffusion in the mono-layer via the change in the fluorescence decay due to the bimolecular quenching reaction [164,165]. [Pg.128]

Sequences such as the above allow the formulation of rate laws but do not reveal molecular details such as the nature of the transition states involved. Molecular orbital analyses can help, as in Ref. 270 it is expected, for example, that increased strength of the metal—CO bond means decreased C=0 bond strength, which should facilitate process XVIII-55. The complexity of the situation is indicated in Fig. XVIII-24, however, which shows catalytic activity to go through a maximum with increasing heat of chemisorption of CO. Temperature-programmed reaction studies show the presence of more than one kind of site [99,1(K),283], and ESDIAD data show both the location and the orientation of adsorbed CO (on Pt) to vary with coverage [284]. [Pg.732]

For a polyatomic, there are many questions on the role of the polyad number in energy flow from the molecule to the bath. Does polyad number conservation in the isolated molecule inlhbit energy flow to the batii Is polyad number breaking a facilitator or even a prerequisite for energy flow Finally, does the energy flow to the bath increase the polyad number breaking in the molecule One can only speculate until these questions become accessible to fiiture research. [Pg.77]

Figure A3.9.2. Interaction potential for an atom or molecule physisorbed on a surface. A convenient model is obtained by squaring off the potential, which facilitates solution of the Sclirodinger equation for the scattering of a quantum particle. Figure A3.9.2. Interaction potential for an atom or molecule physisorbed on a surface. A convenient model is obtained by squaring off the potential, which facilitates solution of the Sclirodinger equation for the scattering of a quantum particle.
Shearing of the data is perfonned to obtam isotropic spectra in the FI dimension and to facilitate easy extraction of the ID slices for different peaks. Shearing is a projection of points that lie on a line with a slope equal to the anisotropy axis onto a line that is parallel to the F2 axis [24]- Shearing essentially achieves the same as the split-t experiment or delayed acquisition of the echo. Although sheared spectra may look more attractive, they do not add any extra infomiation and they are certainly not necessary for the extraction of QIS and values. [Pg.1490]

Wokosin D L, Centonze V, White J G, Armstrong D, Robertson G and Ferguson A I 1996 All-solid-state ultrafast lasers facilitate multiphoton excitation fluorescence imaging IEEE J. Sel. Top. Quantum Electron. 21051-65... [Pg.1674]

Other biomoleciiles imaged have included all DNA bases [44], polysaccharides [45] and proteins [46, 4lZ]. In many cases there is strong evidence that the imaging process is facilitated by the presence of iiltrathin (conducting) water films on the surface of the sample [48, 49 and 50],... [Pg.1685]

A liquid serves as the calorimetric medium in which the reaction vessel is placed and facilitates the transfer of energy from the reaction. The liquid is part of the calorimeter (vessel) proper. The vessel may be isolated from the jacket (isoperibole or adiabatic), or may be in good themial contact (lieat-flow type) depending upon the principle of operation used in the calorimeter design. [Pg.1903]

Liquid crystal phases possess characteristic textures when viewed in polarized light under a microscope. These textures, which can often be used to identify phases, result from defects in tire stmcture. Compendia of micrographs showing typical textures exist to facilitate phase identifications [37, 38]. These monographs also discuss tire origins of defect stmctures in some detail. [Pg.2551]

Other solubilization and partitioning phenomena are important, both within the context of microemulsions and in the absence of added immiscible solvent. In regular micellar solutions, micelles promote the solubility of many compounds otherwise insoluble in water. The amount of chemical component solubilized in a micellar solution will, typically, be much smaller than can be accommodated in microemulsion fonnation, such as when only a few molecules per micelle are solubilized. Such limited solubilization is nevertheless quite useful. The incoriDoration of minor quantities of pyrene and related optical probes into micelles are a key to the use of fluorescence depolarization in quantifying micellar aggregation numbers and micellar microviscosities [48]. Micellar solubilization makes it possible to measure acid-base or electrochemical properties of compounds otherwise insoluble in aqueous solution. Micellar solubilization facilitates micellar catalysis (see section C2.3.10) and emulsion polymerization (see section C2.3.12). On the other hand, there are untoward effects of micellar solubilization in practical applications of surfactants. Wlren one has a multiphase... [Pg.2592]

A large number of studies concerned witli tliiol-tenninated molecules has been directed at tire preparation of tailored organic surfaces, since tlieir importance has been steadily increasing in various applications. Films of o> functionalized alkanetliiols have facilitated fundamental studies of interfacial phenomena, such as adhesion [190, 191], corrosion protection [192], electrochemistry [193], wetting [194], protein adsorjDtion [195, 196] or molecular recognition [197, 198, 199, 200 and 201] to mention only a few. [Pg.2627]

Characterization of zeolites is primarily carried out to assess tire quality of materials obtained from syntliesis and postsyntlietic modifications. Secondly, it facilitates tire understanding of tire relation between physical and chemical properties of zeolites and tlieir behaviour in certain applications. For tliis task, especially, in situ characterization metliods have become increasingly more important, tliat is, techniques which probe tire zeolite under actual process conditions. [Pg.2787]


See other pages where Facilitation is mentioned: [Pg.150]    [Pg.256]    [Pg.354]    [Pg.54]    [Pg.134]    [Pg.510]    [Pg.546]    [Pg.772]    [Pg.151]    [Pg.284]    [Pg.441]    [Pg.269]    [Pg.624]    [Pg.872]    [Pg.1136]    [Pg.1309]    [Pg.1313]    [Pg.1563]    [Pg.1925]    [Pg.2064]    [Pg.2271]    [Pg.2421]    [Pg.2591]    [Pg.2596]    [Pg.2649]    [Pg.2722]    [Pg.2789]    [Pg.2887]    [Pg.2933]   
See also in sourсe #XX -- [ Pg.173 ]

See also in sourсe #XX -- [ Pg.73 ]




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Facilitators

Facilitization

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