Anion exchanger, definition

The, chain voAiantS are characterized by the presence of two abnormal components, an abnormal Hb-F (02 /2) and an abnormal Hb-A (tt2 32) Of these two, the 02 2 component dominates and the 02 32 component Is often difficult to detect. The methods of choice are starch gel electrophoresis and anion-exchange chromatography using DEAE-Sephadex or DE-52 Cellulose. Chain analyses of these Isolated hemoglobin components will lead to a definitive Identification. 

No definite reason for these fluctuations could be identified, but it is known that neptunium, due to its complicated redox chemistry, reacts in a very sensitive way to even minor process variations (7,8). Based on these results the proposal was made (J5) to recover the "co-extracted" portion of the neptunium by running the second plutonium and uranium purification cycles under conditions where the Np is directed into the aqueous raffinates (2AW and 2DW streams). In the Pu purification cycle, this can be done by adding sufficient nitrous acid to keep the Np pentavalent, while in the U purification cycle (which is run under slightly reducing conditions) a low acidity and a high loading help to reject Np into the aqueous 2DW stream. The two raffinate streams are combined in WAK in the 3W evaporator, and the Np is thus collected in the concentrate from this unit (3WW stream). Consequently the proposal was made to recover the Np from this 3WW stream by use of the well-known anion exchange process (9,J ). 

This trend was then expected to be experimentally observed in the values. For the anion exchange ADC separations at 4-8 M HCl (chlorination process according to Eq. 35, no hydrolysis), the trend in the complex formation and Ki values will definitely be continued with Rf, i.e. 

Definition A synthetic anion exchanged polymer in which quaternary ammonium groups are attached to a copolymer of styrene and divinylbenzene Properties Wh. to buff-colored fine powd. odorless to si. amine odor insol. in water, ethanol, chloroform, ether, benzene, org. soivs. stable to 150 C... 

Unit definition One methylase unit is the amount of enzyme that catalyzes the conversion of 1 pmol of [ H]methyl group into a form that binds to anion-exchange filters (e.g., Whatman DE81) in 30 min at 37°C (5). 

A further difficulty is the distinction between a concept and an operation, for example in the definition of ion exchange capacity. Operationally, "the ion exchange capacity of a soil (or of soil-minerals in waters or sediments) is the number of moles of adsorbed ion charge that can be desorbed from unit mass of soil, under given conditions of temperature, pressure, soil solution composition, and soil-solution mass ratio" (Sposito, 1989). The measurement of an ion exchange capacity usually involves the replacement of (native) readily exchangeable ions by a "standard" cation or anion. 

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