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Similarity principles scale

Physical modeling involves searching for the same or nearly the same similarity criteria for the model and the real process. The full-scale process is modeled on an increasing scale with the principal linear dimensions scaled-up in proportion, based on the similarity principle. For relatively simple systems, the similarity criteria and physical modeling are acceptable because the number of criteria involved is limited. For complex systems and processes involving a complex system of equations, a large set of similarity criteria is required, which are not simultaneously compatible and, as a consequence, cannot be realized. [Pg.1037]

S.3.2.3. Scale-up based on similarity principles scale-up correlations... [Pg.227]

It should be no surprise that the methods used to produce most flavourings from plant sources are based on similar principles as those used in the isolation of aroma compounds from foods. However, economics and scale play major roles in dictating methods. Additionally, the physical characteristics of the plant material, and concentrations and properties of flavouring materials also... [Pg.414]

There are a number of commercial homogenizers (e.g., Five-Star, Manton-Gaulin, and Rannie homogenizers) that operate on similar principles (namely, high shear forces and high liquid pressures). These are commonly used for manufacturing emulsions and are adaptable for particle siz< reduction of liposomes in large scale. [Pg.394]

The number of electrons exchanged on a time scale similar to that of a preparative electrolysis is determined by coulometry. A coulometry experiment involves the complete conversion of the substrate to product(s) and, accordingly, C 0 decreases with time, in principle to zero. This is in contrast to the electro analytical methods where C 0 stays essentially constant during the experiments. Coulometry is carried out at either constant potential or constant current and, usually, the solution is stirred magnetically. [Pg.163]

Irrespective of the origin of fractals or fractal-like behavior in experimental studies, the investigator has to derive an estimate for df from the data. Since strict self-similarity principles cannot be applied to experimental data extracted from irregularly shaped objects, the estimation of df is accomplished with methods that unveil either the underlying replacement rule using self-similarity principles or the power-law scaling. Both approaches give identical results and they will be described briefly. [Pg.15]

The Small Scale Shock Reactivity Test (SSRT test) follows a similar principle. In this test, the explosive under investigation ( sample in Fig 7.23) is initiated by a commercial detonator and the depth in a solid aluminum block is measured for example by filling it with fine sand (Si02) and correlating the dent volume with the power of the explosive (Fig. 7.23, Tab. 7.7). [Pg.182]

Because the isotope fractionating processes are not evenly distributed throughout the ocean, temporal variations at fixed points will produce predictable changes in the (5 N of local nitrate pools. As examples (1) an increase in denitrification rates within the water column on the Oman margin would increase the <5 Nni ate of the Arabian Sea thermochne (Altabet et al., 1995 Schafer and Ittekkot, 1993), (2) an increase in N2-fixation in surface waters of the eastern Mediterranean would cause a decrease in d Nnitrate io the eastern Mediterranean thermochne (Stmck et al., 2001), and (3) an increase in relative nitrate consumption in Antarctic surface waters would cause an increase in local near-surface d N itrate (Francois et al., 1997). However, it must be kept in mind that these local signals are imprinted upon any variation in the baseline of mean ocean nitrate. A similar principle operates at finer scales, with... [Pg.1509]

Sr is a simple but very efficient tool for studying surfaces on the submicrometre scale. The principle on which it works is very similar to profilometry, where a hard tip is scanned across the surface and its vertical movements monitored. As a result of the miniature size of the SFM tip, which is mounted at the bottom end of a cantilever-like spring, it is possible to image the corrugation of the surface potential of the sample (Ovemey etal, 1994). [Pg.39]

Similar principles to those for emergency planning for major accidents apply to the planning for smaller scale accidents. [Pg.29]

Normalization. The practice of subtracting the theoretical Compton-modified intensity works only if the measured intensity is available on an absolute scale. Similarly, before the intensity function I(q) can be converted into the interference function i(q) by means of Equation (4.13), I(q) must be on an absolute scale. In principle, the intensity can of course be measured from the beginning in absolute units by means of an instrument calibrated for absolute intensity, as discussed in Section 2.7. The more usual practice, however, is to measure the intensity first in relative units and then to scale it by the normalization constant determined according to the following criterion. The normalization condition is satisfied when the following is obeyed in the limit of large q... [Pg.142]

Thus, dimensionless pi-numbers do not necessarily expose similarity principles, that is, scaling factors are not necessarily invariant numbers. [Pg.276]

AFM is a tool for measuring surface topography on a nanometric scale. The principle is similar to that of contact profilometry with... [Pg.3120]

The kind of mechanisms that lead to gelation characterised by infinite clusters are not clear. The infinite cluster contains of course a finite fraction G(t) of the total mass (M(t) + G(t) = 1). Pre-gel and post-gel states separated by a gelation transition can be analysed in terms of a kinetic equation. Sol-gel transitions are similar to phase transition phenomena. It is not surprising that scale invariance principles elaborated in the theory of phase transition can be adopted for polymer systems. Modern percolation theory (see, for example Stauffer (1979)) offer a conceptual framework to treat cluster formation. [Pg.209]

Scanning tunneling microscopy (STM) was invented by Binnig and Rohrer in 1983 [235], for which they received the Nobel Prize. The ability to produce images related directly to topography on an atomic scale was a major step forward for surface science, which until then had had to deduce surface atomic structure from techniques such as LEED and ISS. Since the appearance of STM, many sister techniques using similar principles have been developed for the study either of special materials, of surfaces in nonvacuum ambients. or of the surface distribution of effects other than purely topographical. [Pg.910]

Similar principles to Problem 7 but easier. Note that the formula to be proved is to be applicable to any substance, not necessarily a gas. The only purpose of the gas, in the question as it is expressed, is to define the 6 scale of temperature. [Pg.463]

However, most solids processing technology do not have this level of maturity yet. In this case, scale-up studies reduce uncertainties in the design and operation of the scaled unit most economically. On this basis, the starting point in scale-up must really be the commercial unit. In theory, once sufficient information for the commercial unit is known, scale-up can be done by applying the similarity principles from data collected on a smaller unit. The similarity principle states (3) Two processes can be considered similar if they take place in similar geometric space and all dimensionless groups required to describe the processes have the same numerical values. [Pg.460]


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See also in sourсe #XX -- [ Pg.112 , Pg.113 , Pg.114 , Pg.115 , Pg.116 , Pg.200 ]




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Similarity principles

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