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Role distance

The second conceptual scheme that relates to understanding stereotypes is that of tourist roles and the notion of role distance. This is a major topic in tourist behaviour analysis and warrants special attention. [Pg.24]

Social roles of the tourist How tourists are viewed, what tourists do, distinctive features of being a tourist, implications of travelling to other places Stereotype analysis Social representations Role theory, including role distance, altercasting, role conflict, role prescriptions The outsider and flaneur roles Liminality and liminoid space... [Pg.189]

A further interaction site involves the atom linked to the sp carbon (an oxygen for aromatic esters, amides and ketones). A hydrogen bond donor, presumably a hydroxylated amino acid, was proposed [39], but a histidine residue could play the same role. Distances between these two determinants have been evaluated and the three-dimensional model mainly based on the initial work of Hibert [38] summarized the presently available data on 5-HTg receptor-ligand interactions (figure 3). [Pg.228]

The major role of TOF-SARS and SARIS is as surface structure analysis teclmiques which are capable of probing the positions of all elements with an accuracy of <0.1 A. They are sensitive to short-range order, i.e. individual interatomic spacings that are <10 A. They provide a direct measure of the interatomic distances in the first and subsurface layers and a measure of surface periodicity in real space. One of its most important applications is the direct determination of hydrogen adsorption sites by recoiling spectrometry [12, 4T ]. Most other surface structure teclmiques do not detect hydrogen, with the possible exception of He atom scattering and vibrational spectroscopy. [Pg.1823]

The pathway model makes a number of key predictions, including (a) a substantial role for hydrogen bond mediation of tunnelling, (b) a difference in mediation characteristics as a function of secondary and tertiary stmcture, (c) an intrinsically nonexponential decay of rate witlr distance, and (d) patlrway specific Trot and cold spots for electron transfer. These predictions have been tested extensively. The most systematic and critical tests are provided witlr mtlrenium-modified proteins, where a syntlretic ET active group cair be attached to the protein aird tire rate of ET via a specific medium stmcture cair be probed (figure C3.2.5). [Pg.2978]

One can see tliat tlie Dexter exchange mechanism is exponentially dependent on tlie distance between tlie donor and acceptor, and as such it begins to play a visible role only at very short distances when tlie electron clouds begin to... [Pg.3026]

Following the similar structure - similar property principle", high-ranked structures in a similarity search are likely to have similar physicochemical and biological properties to those of the target structure. Accordingly, similarity searches play a pivotal role in database searches related to drug design. Some frequently used distance and similarity measures are illustrated in Section 8.2.1. [Pg.405]

Independent molecules and atoms interact through non-bonded forces, which also play an important role in determining the structure of individual molecular species. The non-bonded interactions do not depend upon a specific bonding relationship between atoms, they are through-space interactions and are usually modelled as a function of some inverse power of the distance. The non-bonded terms in a force field are usually considered in two groups, one comprising electrostatic interactions and the other van der Waals interactions. [Pg.199]

The reaction medium plays a very important role in all ionic polymerizations. Likewise, the nature of the ionic partner to the active center-called the counterion or gegenion-has a large effect also. This is true because the nature of the counterion, the polarity of the solvent, and the possibility of specific solvent-ion interactions determines the average distance of separation between the ions in solution. It is not difficult to visualize a whole spectrum of possibilities, from completely separated ions to an ion pair of partially solvated ions to an ion pair of unsolvated ions. The distance between the centers of the ions is different in... [Pg.404]

A number of methods have been developed to introduce context to on-line databases, enabling searches to be refined to minimized false retrieval. One of the earliest techniques is proximity searching, in which two words are required to be adjacent, or within a limited distance from each other in text. The assignment of roles to chemical substances is a method of precoordinating concepts. A substance can be identified as a reactant, as a product, and in some systems in a number of additional roles. For example, by searching for documents in which formaldehyde is a product, documents in which it is a reactant, or in which it undergoes no reaction, are thus eliminated. [Pg.59]

The events are so fine-tuned and the size of chamber, pressure of gas, travel, distance of the moving contact and the size of blast nozzle so designed and adjusted that a near-slrike-free interruption can be achieved for low reactive currents (inductive or capacitive) as well as fullload and very heavy fault currents. The advance compression of gas through the movement of main contact plays an important role by storing a part of the gas even before opening of the arcing contacts. [Pg.641]

Vibrational energy, which is associated with the alternate extension and compression of die chemical bonds. For small displacements from the low-temperature equilibrium distance, the vibrational properties are those of simple harmonic motion, but at higher levels of vibrational energy, an anharmonic effect appears which plays an important role in the way in which atoms separate from tire molecule. The vibrational energy of a molecule is described in tire quantum theory by the equation... [Pg.44]

Further support for this approach is provided by modern computer studies of molecular dynamics, which show that much smaller translations than the average inter-nuclear distance play an important role in liquid state atom movement. These observations have conhrmed Swalin s approach to liquid state diffusion as being very similar to the calculation of the Brownian motion of suspended particles in a liquid. The classical analysis for this phenomenon was based on the assumption that the resistance to movement of suspended particles in a liquid could be calculated by using the viscosity as the frictional force in the Stokes equation... [Pg.293]

There is a large range of resins available for SPOS. These resins are derivatised polymer supports with a range of linkers. The roles of linkers are (i) to provide point(s) of attachment for the tethered molecule, akin to a solid supported protecting group(s), (ii) to provide distance from the polymeric backbone in order to minimise interactions with the backbone, (iii) to enable cleavage of product molecules under conditions compatible with the stability of the molecules and the reaction conditions employed for chemical transformations. Hence in order to... [Pg.74]

Thus far we have discussed the direct mechanism of dissipation, when the reaction coordinate is coupled directly to the continuous spectrum of the bath degrees of freedom. For chemical reactions this situation is rather rare, since low-frequency acoustic phonon modes have much larger wavelengths than the size of the reaction complex, and so they cannot cause a considerable relative displacement of the reactants. The direct mechanism may play an essential role in long-distance electron transfer in dielectric media, when the reorganization energy is created by displacement of equilibrium positions of low-frequency polarization phonons. Another cause of friction may be anharmonicity of solids which leads to multiphonon processes. In particular, the Raman processes may provide small energy losses. [Pg.20]

Health effects attributed to sulfur oxides are likely due to exposure to sulfur dioxide, sulfate aerosols, and sulfur dioxide adsorbed onto particulate matter. Alone, sulfur dioxide will dissolve in the watery fluids of the upper respiratory system and be absorbed into the bloodstream. Sulfur dioxide reacts with other substances in the atmosphere to form sulfate aerosols. Since most sulfate aerosols are part of PMj 5, they may have an important role in the health impacts associated with fine particulates. However, sulfate aerosols can be transported long distances through the atmosphere before deposition actually occurs. Average sulfate aerosol concentrations are about 40% of average fine particulate levels in regions where fuels with high sulfur content are commonly used. Sulfur dioxide adsorbed on particles can be carried deep into the pulmonary system. Therefore, reducing concentrations of particulate matter may also reduce the health impacts of sulfur dioxide. Acid aerosols affect respiratory and sensory functions. [Pg.39]

Another effect of elastic deformation is that it causes a long-range interaction between steps. From the continuum elasticity theory, two steps sepa-rated by a distance have a repulsive interaction proportional to l for homo- and to In i for hetero-epitaxial cases, respectively [84]. This interaction plays an important role, for example, in step fluctuations, terrace width distribution, step bunching, and so forth [7,85-88]. [Pg.880]


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See also in sourсe #XX -- [ Pg.21 , Pg.186 ]




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