Sorption sites composition

This assumption conveniently permits multicomponent cases to be treated as composites of single-component cases the behavior of each species can be calculated separately and the results be superimposed on one another. The assumption is quite acceptable for analytical chromatography at low concentrations and low degree of sorbent loading but becomes untenable at high concentrations or in ion exchange with high conversion, because the solute species then affect one another s sorption behavior as they compete for the limited number of available sorption sites. In equilibrium, the stationary-phase concentration of species i then depends on the mobile-phase concentrations of all species present rather than only on that of i ... 

Discrete and continuum models of transfer of molecules over various sorption sites of a microheterogeneous membrane were considered for systems with weak intermolecular interactions and membranes with constant composition and structure. An equation for estimating size effects on permeability coefficient II of microheterogeneous membranes was derived [188], and the possibility of applying the continuum model to calculate the n value in thin films of thickness L is numerically analyzed. The effect of the composition and structure of a uniformly microheterogeneous membrane on the permeability coefficients II was studied. The dependence of n on the composition is a convex function if the migration between different sorption sites proceeds more quickly than between identical sites and a concave one in the opposite case [189],... 

These membranes are beneficial to separate CO2/H2 mixture as well. While conventional polyimides exhibited higher permeability for H2 than that of CO2, polyether-containing polyimides showed reverse selective characteristics. As increasing the chain length and molar composition in the block copolymer, CO2 permeability as well as CO2/H2 selectivity improved simultaneously. As highly condensable CO2 competed with H2 for the sorption sites in hard segment, mixed... 

Root products may be classified into types on the basis of their (1) chemical properties, such as composition, solubility, stability (e.g., hydrolysis, oxidation), volatility, molecular weight etc. (2) site of origin and (3) e.stablished, not just perceived, functions. The chemical properties determine in turn their biological activity and how the compounds will behave in soils their persistence in soil is very much an outcome of their chemical behavior, particularly sorption and their biodegradability. 

SSZ-35 the reactions would be influenced by the presence of very strong Lewis sites. Quantitative sorption of ammonia, pyridine and d3-acetonitrile in both zeolites showed that the real number of acidic groups was close to values, derived form the number of aluminum atoms (taken from AAS analysis) in the idealized unit cell. Obtained values are 1.1 H+/u.c. for SSZ-33 with idealized unit cell composition H2.9[Al2.9Si53.iOii2] (plus 1.3 Lewis sites per u.c.) and 0.3 H+/u.c. for SSZ-35 with ideal formula Ho.4[Alo.4Sii5 6032] (plus 0.05 Lewis sites per u.c.). 

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