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Molecular range

The API method is a generalized method that predicts mole fraction of paraffinic, naphthenic, or aromatic compounds for an olefin-Ifee hydrocarbon. The development of the equations is based on dividing the hydrocarbon into two molecular ranges heavy fractions (200 < MW < 600) and light fractions (70 < MW <200). Appendix 7 contains API correlations applicable to the FCC feed. [Pg.78]

Filtration is the separation of solids from a fluid. While various filtration processes do, in fact, include separation in the ionic and molecular ranges, here we are primarily concerned with particulate filtration. Traditionally, a filter medium is employed to remove particles in the range of 1 to 1,000 micron ( x). [Pg.320]

On one hand, /z-alkanes of the molecular range C10-C16 are important starting materials for the synthesis of anionic surfactants. It is possible to dehydrogenate these hydrocarbons to isomeric /z-olefins with internal double bonds olefins) [4], which are also important initial products for the synthesis of an-... [Pg.5]

Ionic Range Molecular Range Macro Molectiliir Ran e Micro Particle Range... [Pg.38]

We take here the specific pair distribution the result fia — I/O may then easily be demonstrated for distances larger than molecular range, using an argument similar to the one that follows. [Pg.255]

The humates present in soil are polyelectrolytes and bear some similarity to polyacrylic acid and polymethacrylic acid (49, 50). The molecular weight distribution for the humates is considerable fulvic acid fractions of 1,000 daltons have been isolated (51) while humic acid molecular weights obtained by gel chromatography are in the range 17,000 to 100,000 daltons according to the type of soil from which it was extracted (52). However, ultracentrifugation analysis indicates a molecular range of 2,000 to 1,500,000 daltons for humic acids (55). [Pg.57]

Nano-sized metal particles are usually present in the supported metallic catalysts used industrially. The smaller the particle size, the larger the fraction of metal surface atoms exposed, which are therefore accessible to reactants. However, as the size of the metal particles decreases to the molecular range, their properties and, consequently, their catalytic behavior change. Both well-defined metal clusters and small metal aggregates can be generated by applying proper activation... [Pg.315]

Molecular Range Macromolecular Range Microparticle Range... [Pg.493]

As already noted in the Introduction, such a behavior can be attributed to two contrary effects. For small particles, i.e., particle sizes in the transition and free molecular range, the potential well is not deep whereas the decay length of the potential is greater than the particle size. Therefore, the collisions may be less effective because of the shallow potential well (i.e., the sticking probability may be less than unity), whereas the rate of collisions between the particles may increase because of the increase in the effective collision cross section caused by the increased... [Pg.45]

Skinny molecular range, [af, a< ) af is defined above, whereas is the maximum threshold at and below which all locally nonconvex domains on the surface of density domains are simply connected. In simpler terms, in the skinny molecular range all nuclei are found within a single density domain, but there are formal "neck regions on the surface of density domains. In the terminology of shape group analysis [2], rings of D) type can be found on the surface of density domains. [Pg.184]

Corpulent molecular range, [ac, aq) ac is defined above, whereas aq is the maximum threshold at and below which all density domains... [Pg.184]

Quasi-spherical molecular range, [aq, amjn) both aq and amjn are defined above. For any threshold value within the quasi-spherical range the density domain representing the molecule is convex. If amjn is small enough, then in the strict mathematical sense, for very low density thresholds all molecules have convex density domains. [Pg.185]

In recent years much attention has been given to the application of fractal analysis to surface science. The early work of Mandelbrot (1975) explored the replication of structure on an increasingly finer scale, i.e. the quality of self-similarity. As applied to physisorption, fractal analysis appears to provide a generalized link between the monolayer capacity and the molecular area without the requirement of an absolute surface area. In principle, this approach is attractive, although in practice it is dependent on the validity of the derived value of monolayer capacity and the tacit assumption that the physisorption mechanism remains the same over the molecular range studied. In the context of physisorption, the future success of fractal analysis will depend on its application to well-defined non-porous adsorbents and to porous solids with pores of uniform size and shape. [Pg.5]

In SE 33, the other example of a forensic genetic marker amenable to effective CE separation, alleles differing by as little as 4 bp, in a molecular range of 230 to 350 bp, exist, with potentially 2 bp repeats (half-alleles). This similarity poses much higher analytical demands on the separation power of CE. Notably, CE carried out in 1.27 mM ethidium bromide and 0.5% hydroxyethylcellulose was capable of resolving an allelic test mixture. This example shows, much more than D1S80, the potential of CE in forensic biology. [Pg.199]

The molecular density range can be subdivided into subranges. At the highest threshold values within the molecular range, the DD has some local "neck" region, that is, there is at least one topological belt or some other multiply connected set on the surface of the density domain along which the surface is not locally convex. (Note that within any multiply connected set there are loops which cannot... [Pg.47]

Finally, the scale distinction is also recognized in the interpretation of contact angles. In secs. 2.5c and 2.11b we saw that surface tensions, and hence contact angles, can to a first approximation be Interpreted in terms of an additive contribution of dispersion forces and a non-dispersive contribution (say, hydrogenbridging in water). These forces act across the entire bulk of each phase tmd, at least for London-Van der Waals forces they have a colloided range. On the other hand, a limited adsorption of surfactants, which only act over a molecular range, drastically modifies the wetting behaviour. [Pg.565]

As we have seen earlier, [tj] may be calculated directly from the (absolute) MAES measurements of M and using Eq. (5). For linear polymers spanning a relatively broad molecular range (an order of magnitude or more), the measurement of M and permits the determination of the molecular conformation defined by... [Pg.745]

Molecular density range All nuclei of the molecule are found within a common density domain, establishing the essential molecular pattern of bonding. Skinny molecular range There exists at least one multiply connected set on the surface of the density domain DD(X,a) along which the density domain is not locally convex (such as a formal neck region ). [Pg.179]


See other pages where Molecular range is mentioned: [Pg.177]    [Pg.435]    [Pg.228]    [Pg.588]    [Pg.23]    [Pg.18]    [Pg.24]    [Pg.977]    [Pg.55]    [Pg.227]    [Pg.31]    [Pg.45]    [Pg.46]    [Pg.46]    [Pg.47]    [Pg.185]    [Pg.187]    [Pg.67]    [Pg.631]    [Pg.666]    [Pg.666]    [Pg.48]    [Pg.566]    [Pg.631]    [Pg.631]    [Pg.25]    [Pg.215]   
See also in sourсe #XX -- [ Pg.47 ]




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