Capacity anion

Where an organic trap is part of a demineralization plant system, it is placed in the train upstream of the strong base anion (SBA) resin unit. When the organic trap resin is placed within the same pressure vessel, physically on top of the anion resin (stratified bed), in which case, as it forms part of the overall anion capacity, a weak base anion resin operating in the free base form is employed. 

The anion-responsive properties of PVI-dispersed Dixon Air-Spun 200-10 were then tested against mixed acid-treated Aquadag. The result was positive, the anion capacity being comparable to the cation capacity of similar material dispersed with TA. The oxidizable iodide ion originally present in the electrode, if incompletely exchanged by chloride in the demineralization cell, would doubtless contribute something to anion responsiveness. 

A cation-responsive electrode can associate cations with chemical bonds therefore, its cation capacity is always higher than its anion capacity. In this case, the total capacity is limited solely by the anion capacity. On the other hand, the total capacity of an anion-responsive electrode is limited by its cation capacity. 

Figure 3.4. Eluent pH vs. anion capacity factor, k. Conditions 100 x 4.6 mm (multicharge, weak base, anion exchanger) column, 15 mM sodium perchlorate eluent, UV detection at 200 nm (from Ret [10], with permission).

Figure 3.4 Eluent pH vs. anion capacity factor, Id. Conditions ...

Although a crown ether-coated column can effectively separate cations and its anion capacity can be adjusted by controlling the amount of adsorbed crown ether, it is susceptible to loss of the macrocyclic active site. When water eluents are used, this is generally not a problem, but if mixed mobile phase solvents are used (e.g., water/methanol), the coated crown ether can be washed off the column resulting in a loss of capacity. ... 

Polymeric coagulants do not affect pH therefore, the need for supplemental alkalinity, such as lime, caustic, or soda ash, is reduced or eliminated. Polymeric coagulants do not add to the total dissolved soHds concentration, eg, 1 ppm of alum adds 0.45 ppm of sulfate ion (expressed as CaCO ) the reduction ia sulfate can significantly extend the capacity of anion-exchange systems. 

Molecular Interactions. Various polysaccharides readily associate with other substances, including bile acids and cholesterol, proteins, small organic molecules, inorganic salts, and ions. Anionic polysaccharides form salts and chelate complexes with cations some neutral polysaccharides form complexes with inorganic salts and some interactions are stmcture specific. Starch amylose and the linear branches of amylopectin form inclusion complexes with several classes of polar molecules, including fatty acids, glycerides, alcohols, esters, ketones, and iodine/iodide. The absorbed molecule occupies the cavity of the amylose helix, which has the capacity to expand somewhat to accommodate larger molecules. The starch—Hpid complex is important in food systems. Whether similar inclusion complexes can form with any of the dietary fiber components is not known. 

The component reactions in eqn. (2) are very fast, and the system exists in equilibrium. Additional carbon dioxide entering the sea is thus quickly converted into anions, distributing carbon atoms between the dissolved gas phase, carbonate and bicarbonate ions. This storage capacity is clear when the apparent equilibrium constants for the two reactions in eqn. (2) are examined, namely... 

TABLE 15. Cation exchange BEAD FORM Capacity (meq/g) ION-EXCHANGE PACK AGINGS Anion exchange Capacity (meq/g)... 

There also exists a type of resin with no functional groups attached. This resin offers no capacity to the system but increases regeneration efficiency in mixed-bed exchangers. These inert resins are of a density between cation and anion resins and when present in... 

Variances in resin performance and capacities can be expected from normal annual attrition rates of ion-exchange resins. Typical attrition losses that can be expected include (1) Strong cation resin 3 percent per year for three years or 1,000,000 gals/ cu.ft (2) Strong anion resin 25 percent per year for two years or 1,000,000 gals/ cu.ft (3) Weak cation/anion 10 percent per year for two years or 750,000 gals/ cu. ft. A steady falloff of resin-exchange capacity is a matter of concern to the operator and is due to several conditions ... 

Anion A negatively charged ion in an electrolyte solution, attracted to the anode under the influence of a difference in electrical potential. Chloride is an anion. Anion exchange capacity Sum total of exchangeable anions that a soil can adsorb. Expressed as centimoles of negative charge per kilogram of soil. 

The smooth conversion of the enol acetate (151) into an A -acyl derivative (152) under extremely mild conditions points to the high acylating capacity of these esters. This cleavage of isoxazolium salts is also caused by other anions of carboxylic acids, and thus they can be readily converted to reactive enol esters. A very convenient and specific synthesis of peptides due to Woodward et is based on... 

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