Zinc enrichment factor

Zinc is accumulated in gastropods, jellyfish, and sea anemones by an enrichment factor of 3.2 x 104. Scallops concentrate zinc from sea water by a factor of 2.8 x 104 the metal is preferentially accumulated in the kidneys of scallops where 2630 ppm have been found (material dried at 110 °C)59). 

LC of a column packed with the cryptand polymer was used for the separation of zinc isotopes. The enrichment factors were a(67/66) = 0.99967 ... 

Trace metals, such as copper, nickel, cobalt, zinc, and various rare earth elements, tend to coprecipitate with or adsorb onto Fe-Mn oxides. As shown in Table 18.1, this causes these elements to be highly enriched in the hydrogenous deposits as compared to their concentrations in seawater. The degree of enrichment is dependent on various environmental factors, such as the redox history of the underlying sediments and hydrothermal activity. This makes the composition of the oxides geographically variable. 

Many of the micron-sized interplanetary dust particles (IDPs) have approximately chondritic bulk composition (see Chapter 1.26 for details). Porous IDPs match the Cl composition better than nonporous (smooth) IDPs. On an average, IDPs show some enhancement of moderately volatile and volatile elements (see Palme, 2000). Arndt et al. (1996) found similar enrichments in their suite of 44 chondritic particles (average size 17.2 1.2 p.m). The elements chlorine, copper, zinc, gallium, selenium, and rubidium were enriched by factors of 2.2-2.7. In addition, these... 

At the reaction temperature the products, (NaF)i.5Alp3 and the solution of zirconium and hafnium in zinc, are two immiscible liquids. The lighter salt phase, enriched in hafnium to 27 w/o, is drawn off at point 4, leaving a heavier metallic zinc solution of zirconium containing 0.1126 w/o hafnium at point 3. These compositions ate consistent with the separation factor of 328 ... 

Adsorptive stripping voltammetry (ASV) is another specialised technique where the SMDE electrode is used for reducible species and carbon paste electrodes for oxidisable ones. This allows enrichment (by factors of 100-1000) of ions at the working electrode before stripping them off for measurement this improves the detection limits. This technique is rapid, sensitive (10 "M), economical and simple for trace analysis. The basic instrumentation for stripping analysis is apotentiostat (with voltammetric analyser), electrode and recorder. While voltammetry is generally very useful for compounds that do not have a chromophore or fluorophore, stripping analysis is the best analytical tool for direct, simultaneous determination of metals of environmental concern, e.g. lead, cadmium, zinc and copper in sea water. 

Differentiation of sedimentary metal phases was performed on grain size fractionated samples from the lower Rhine River by successive chemical leaching (review). Pollution affects the significant increase of nonresidual associations of chromium, cop er, lead, and zinc. Except for manganese the metal contents in most of the extracted phases decrease as the grain size increases. Phase concentration factors (PCF relative enrichment of metal content in major carrier substances) are high for chromium in moderately reducible phases (20-fold increase in clay-sized particles), for manganese and zinc in the easily reducible sediment fraction (30- and 55-fold enrichment), and for copper and zinc in the carbonates (15 or 25 times compared with total sediment). 

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