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Self static

The atoms on the outennost surface of a solid are not necessarily static, particularly as the surface temperature is raised. There has been much theoretical [12, 13] and experimental work (described below) undertaken to investigate surface self-diffiision. These studies have shown that surfaces actually have dynamic, changing stmetures. For example, atoms can diflfiise along a terrace to or from step edges. When atoms diflfiise across a surface, they may move by hopping from one surface site to the next, or by exchanging places with second layer atoms. [Pg.292]

Tbe use of special motors was more relevant until the 1980s. when solid-state technology was still in its infancy and wa.s not so widely applied. With the advent of static drives, as discus.sed in Sections 6.2-6.4, the use of standard motors is gradually becoming more common for all these applications. The drive it.self can alter the supply parameters to the required level to make a standard motor operate and perform within desired parameters, besides conserving energy. The purpose of describing a few of these applications is only to indicate their non-standard features, where a standard motor with normal controls may not be able to perform the required duties. [Pg.170]

In contrast to static properties, where LP and GM reveal generally the same behavior as that of conventional polymers, due to the self-assembling nature of the breakdown process the transport properties of GM are much more complex. Like conventional polymers, these materials are highly viscoelastic [73,74] and their novel rheology has been intensively studied recently, both experimentally [75,76] and theoretically [11,31,77-79]. A theoretical model... [Pg.544]

A. Static Methods self-avoiding random walks... [Pg.555]

A. Static Methods Self-avoiding Random Walks... [Pg.559]

It is also important to realize that chemistry is not a static body of knowledge as defined by the contents of a textbook. Chemistry came from somewhere and is at present heading in various specific directions. It is a living self-stimulating discipline, and we have tried to transmit this sense of growth and excitement by reference to the historical development of the subject when appropriate. The chemistry of the elements is presented in a logical and academically consistent way but is interspersed with additional material which illuminates, exemplifies, extends or otherwise enhances the chemistry being discussed. [Pg.1363]

There are a number of NMR methods available for evaluation of self-diffusion coefficients, all of which use the same basic measurement principle [60]. Namely, they are all based on the application of the spin-echo technique under conditions of either a static or a pulsed magnetic field gradient. Essentially, a spin-echo pulse sequence is applied to a nucleus in the ion of interest while at the same time a constant or pulsed field gradient is applied to the nucleus. The spin echo of this nucleus is then measured and its attenuation due to the diffusion of the nucleus in the field gradient is used to determine its self-diffusion coefficient. The self-diffusion coefficient data for a variety of ionic liquids are given in Table 3.6-6. [Pg.119]

A seating application is a more complicated static load problem than the building example just reviewed because of the loading situation. The self load on a chair seat is a small fraction of the normal load and can be neglected in the design. The loads are applied for relatively short periods of time of the order of 1 to 5 hours, and the economics of the application requires that the product be carefully designed with a small safety factor. [Pg.250]

In spite of the problems associated with the static structure, the coarsegrained model for BPA-PC did reproduce the glass transition of this material rather well the self-diffusion constant of the chains follows the Vogel-Fulcher law [187] rather nicely (Fig. 5.10),... [Pg.126]

Velocity distribution along x, y and z compared together with the x velocity distribution, and with the computed distribution caused by self- the velocity distribution caused by self-diffu-diffusion ( static"). Flow rates 4.8 mL min- si°n ( static ) is displayed. [Pg.463]

In the stress analysis of pressure vessels and pressure vessel components stresses are classified as primary or secondary. Primary stresses can be defined as those stresses that are necessary to satisfy the conditions of static equilibrium. The membrane stresses induced by the applied pressure and the bending stresses due to wind loads are examples of primary stresses. Primary stresses are not self-limiting if they exceed the yield point of the material, gross distortion, and in the extreme situation, failure of the vessel will occur. [Pg.809]

The confined type of aquifer has a hydraulic pressure (static head) that is on a higher level than the top of the aquifer. This artesian pressure can sometimes reach above the surface level resulting in self flowing wells (artesian wells). [Pg.162]

The electrostatic energy is calculated using the distributed multipolar expansion introduced by Stone [39,40], with the expansion carried out through octopoles. The expansion centers are taken to be the atom centers and the bond midpoints. So, for water, there are five expansion points (three at the atom centers and two at the O-H bond midpoints), while in benzene there are 24 expansion points. The induction or polarization term is represented by the interaction of the induced dipole on one fragment with the static multipolar field on another fragment, expressed in terms of the distributed localized molecular orbital (LMO) dipole polarizabilities. That is, the number of polarizability points is equal to the number of bonds and lone pairs in the molecule. One can opt to include inner shells as well, but this is usually not useful. The induced dipoles are iterated to self-consistency, so some many body effects are included. [Pg.201]


See other pages where Self static is mentioned: [Pg.351]    [Pg.231]    [Pg.484]    [Pg.795]    [Pg.500]    [Pg.98]    [Pg.422]    [Pg.804]    [Pg.90]    [Pg.579]    [Pg.818]    [Pg.801]    [Pg.508]    [Pg.692]    [Pg.178]    [Pg.249]    [Pg.218]    [Pg.769]    [Pg.1038]    [Pg.81]    [Pg.94]    [Pg.143]    [Pg.170]    [Pg.114]    [Pg.187]    [Pg.239]    [Pg.776]    [Pg.128]    [Pg.107]    [Pg.108]    [Pg.463]    [Pg.122]    [Pg.367]    [Pg.193]    [Pg.195]    [Pg.197]    [Pg.227]    [Pg.235]   
See also in sourсe #XX -- [ Pg.167 ]

See also in sourсe #XX -- [ Pg.239 ]




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