Sorption characteristic

WA Hunke, LE Matheson. Mass properties of Co(polycthcr) polyurethane membranes. Part 2. Permeability and sorption characteristics. Int J Pharm 1313-1318, 1981. 

The primary active surface that interacts with the chemical in the sorption process has been shown to be the organic fraction of the soil(6-10). Therefore, the sorption characteristics of a chemical can be normalized to obtain sorption constant based on organic carbon (K ) which is essentially independent of any soil. 

In a study of thermal stability and hydrogen sorption characteristics of a series of sorbent tablets composed of hydride-forming metals dispersed in polymers under a 50% hydrogen in argon atmosphere, it was found that tablets of 80% palladium in PTFE, and 80% of 1 5 atom lanthanum-nickel alloy in PTFE could not be used above 247° C because of explosive decomposition of the PTFE. 

Hassett JJ, Banwart WL, Griffin RA. 1983. Correlation of compound properties with sorption characteristics of nonpolar compounds by soils and sediments concepts and limitations. In Francis CW, Auerbach SI, Jacobs VA, eds. Environment and solid wastes characterization, treatment, and disposal. Boston, MA Butterworths, 161-176. 

Boyd SA, Mortland MM, Chiou CT (1988a) Sorption characteristics of organic compounds on hexadecyltrimethylammonium-smectite. Soil Sci Soc Am J 52 652-657... 

The sorption of water by excipients derived from cellulose and starch has been considered by numerous workers, with at least three thermodynamic states having been identified [82]. Water may be directly and tightly bound at a 1 1 stoichiometry per anhydroglucose unit, unrestricted water having properties almost equivalent to bulk water, or water having properties intermediate between these two extremes. The water sorption characteristics of potato starch and microcrystalline cellulose have been determined, and comparison of these is found in Fig. 11. While starch freely adsorbs water at essentially all relative humidity values, microcrystalline cellulose only does so at elevated humidity values. These trends have been interpreted in terms of the degree of available cellulosic hydroxy groups on the surfaces, and as a function of the amount of amorphous material present [83]. 

Krokida, M.K., Karathanos, V.T., and Maroulis, Z.B. 2000a. Effect of osmotic dehydration on color and sorption characteristics of apple and banana. Dry. Technol. 18, 937-950. 

ZLOKARNIK, M. Adv. Biochem. Eng. 8 (1978) 133. Sorption characteristics for gas-liquid contacting in mixing vessels. 

Of the various equilibrium and non-equilibrium sorption isotherms or sorption characteristics models, the most popular are the Langmuir and Freundlich models. The correct modeling of an adsorbate undergoing both transport and adsorption through a clay soil-solid system necessitates the selection of an adsorption isotherm or characteristic model which best suits the given system. The use of an improper or inappropriate adsorption model will greatly affect the... 

Since TOC, for some solid wastes, was used as a criterion to measure leachate sorption for organic compounds, TOC by itself is considered as a single component system (i.e., SCS, see Sect. 2.1). To represent the SCS equilibrium system for various waste materials, the sorption characteristics of different soils and sediments were analyzed and evaluated using three different sorption iso-... 

It is important to differentiate between the two different types of sorption/ desorption tests (i. e.,batch and column-leaching), and the sorption characteristics determined from one should not be confused with the other. Sorption isotherms obtained with batch equilibrium tests are applied mainly to solid suspensions. The physical model, assumed with this situation, is one of a completely dispersed solid particle system, where all solid particle surfaces are exposed and available for interactions with the contaminants of concern. In contrast, column-leaching tests are performed with intact solid samples, and the sorption characteristics obtained from them are the results of contaminant interactions with a structured system where not all-solid particle surfaces are exposed or available for interactions with the contaminants. 

The Li-Mg-B-N-H structure possesses storage capacity of more than 10 wt.% at around 150-200 "C. However, the reversibility of the hydrogen sorption characteristics was determined using pressure-composition isotherms as shown in Figure 6. From this study, we found reversible hydrogen absorption-desorption behavior (-3-4 wt.%) of the new complex hydride Li-Mg-B-N-H. The improvement in temperature and reversible hydrogen storage capacity were unaffected even after ten... 

Razzaque, M.A. and Banks, W.B. (1982). Dimensional stability and sorption characteristics of wood treated with alkylene oxide. Bano Biggyan Patrika, 11(1/2), 17-23. 

Pulsed field gradient (PFG)-NMR experiments have been employed in the groups of Zawodzinski and Kreuer to measure the self-diffusivity of water in the membrane as a function of the water content. From QENS, the typical time and length scales of the molecular motions can be evaluated. It was observed that water mobility increases with water content up to almost bulk-like values above T 10, where the water content A = nn o/ nsojH is defined as the ratio of the number of moles of water molecules per moles of acid head groups (-SO3H). In Perrin et al., QENS data for hydrated Nation were analyzed with a Gaussian model for localized translational diffusion. Typical sizes of confining domains and diffusion coefficients, as well as characteristic times for the elementary jump processes, were obtained as functions of A the results were discussed with respect to membrane structure and sorption characteristics. ... 

M.Y. Song, S.N. Kwon, S.H. Hong, D.R. Mumm, l.S. Bae, Improvement of hydrogen-sorption characteristics of Mg by reactive mechanical grinding with Cr Oj prepared by spray conversion, Int. J. Hydrogen Ener. 31 (2006) 2284-2291. 

Here again we are concerned with the equilibrium sorption characteristics for all available sorption processes. Also, we need to have sufficient knowledge of the sorption mechanisms and kinetics to relate geologic to laboratory conditions. Likewise we require a comparable understanding of the displacement and release processes which permit migration to proceed. 

Another study examined the influence of hygroscopic ingredients on the sorption characteristics of tablets in a standard tablet formulation [33]. 

Surface Groups. Another factor affecting sorption characteristics is the chemical nature of the adsorbing surfaces. Solid sorbent surfaces may contain hydroxyl or phenyl groups, acid or base groups, or even reactive groups such as olefins. Polarities also... 

The water sorption characteristics of dairy products (like those of most other foodstuffs) are governed by their non-fat constituents (principally lactose and proteins). However, in many milk and whey products, the situation is complicated by structural transformations and/or solute crystallization. 

Despite some conflicting evidence (Kinsella and Fox, 1986), it appears that denaturation has little influence on the amount of water bound by whey proteins. However, other factors which may accompany denaturation (e.g. Maillard browning, association or aggregation of proteins) may alter protein sorption behaviour. Drying technique affects the water sorption characteristics of WPC. Freeze-dried and spray-dried WPC preparations bind more water at the monolayer level than do roller-, air- or vacuum-dried samples, apparently due to larger surface areas in the former. As discussed above, temperature also influences water sorption by whey protein preparations. The sorption isotherm for /Mactoglobulin is typical of many globular proteins. 

In milk powders, the caseins are the principal water sorbants at low and intermediate values of aw. The water sorption characteristics of the caseins are influenced by their micellar state, their tendency towards self-association, their degree of phosphorylation and their ability to swell. Sorption isotherms for casein micelles and sodium caseinate (Figure 7.14) are generally sigmoidal. However, isotherms of sodium caseinate show a marked increase at aw between 0.75 and 0.95. This has been attributed to the... 

---