Uranium uptake

Millard, A.R. and Hedges, R.E.M. 1995 The role of the environment in uranium uptake by buried bone. Journal of Archaeological Science 22 239-250. 

Bones and teeth, however, are primary archaeological materials and are common to many archaeological sites. Bones bearing cut marks from stone tools are a clear proxy for human occupation of a site, and in the study of human evolution, hominid remains provide the primary archive material. Hence, many attempts have been made to directly date bones and teeth using the U-series method. Unlike calcite, however, bones and teeth are open systems. Living bone, for example, contains a few parts per billion (ppb) of Uranium, but archaeological bone may contain 1-100 parts per million (ppm) of Uranium, taken up from the burial environment. Implicit in the calculation of a date from °Th/U or Pa/ U is a model for this Uranium uptake, and the reliability of a U-series date is dependent on the validity of this uptake model. 

Millard, A. R. (1993), Diagenesis of Archaeological Bone The Case of Uranium Uptake, Oxford Univ. Press, Oxford, UK. 

Millard, A. R. and Hedges, R. E. M. (1996). A diffusion-adsorption model of uranium uptake by archaeological bone. Geochimica et Cosmochimica Acta 60 2139-2152. 

The uranium accumulation of tooth enamel is negligibly small while it can be appreciable for dentine. Hence, the efforts to determine the y-ray dose from the external dentine to enamel must be made to assess the equivalent dose, ED, considering the linear uranium uptake and early as well as late uranium uptake using polynomial formula for some fossils. Laboratory experiments indicated that fresh enamel did not accumulate uranium rapidly but dentine did.8182 The author argue that fitting to a saturation curve rather than a meaningless poly-nominal should be made in a model calculation of uranium-uptake.1... 

Rufyikiri, G., Thiry, Y. Declerck, S. (2003). Contribution of hyphae and roots to uranium uptake and translocation by arbuscular mycorrhizal carrot roots under root-organ culture conditions. New Phytologist, 158, 391-9. 

Richardson, D. H. S., Kiang, S., Ahmadjian, V. Nieboer, E. (1985). Lead and uranium uptake in lichens. In Lichen Physiology and Cell Biology, ed. D. H. Brown. 

Ahsanullah M, Williams AR. 1989. Kinetics of uranium uptake by the crab Pachygrapsus laevimanus and the zebra winkle Austrocochlea constricta. Marine Biology 101 323-327. 

Amounts of U absorbed by spinach grown in Andosols under field conditions were 2.36 0.13 Lig kg in leaves and 0.93 0.05 pg kg in petioles. The U concentrations in spinach leaves and petioles were significantly related to Fe and Al concentrations. Uranium uptake by spinach is accompanied by Fe and Al uptake. 

Moreover, the performance of the sorbent must be suitable for bringing it into contact with the vast volumes of sea water. Most imperative requirements pertain to the uranium uptake kinetics the sorbent should be qualified for a rapid rate of loading in order to minimize the sorbent inventory. The quantity of required sorbent material ms (tons of dry sorbent) is determined by the production rate P (tons of uranium per day) of a projected recovery plant, by the uranium loading b of the sorbent (ppm uranium per cycle based upon dry weight) and by the duration t (days per cycle) of a complete sorption-elution cycle ... 

Since the elution step normally proceeds rapidly as compared to the period of sorption, the inventory of the sorbent turns out to be inversely proportional to the rate of uranium uptake 130). 

The uranium uptake rate of hydrous titanium oxide is demonstrated in Fig. 7. 

Fig. 7. Uranium uptake of hydrous titanium oxide granules 0.6 and 0.9 mm in diameter in dependence on time1 2)...

The uranium uptake rate increases with decreasing granular size because of the specific surface enlargement. Yet, after ten days both curves show a distinct flattening. After this time, hydrous titanium oxide granules of 0.6 mm diameter attain a uranium loading of 100 ppm. The demonstrated uptake rates seem to be realistic for mechanically rather stable hydrous titanium oxide granules. 

During the first ten days uranium loadings were between 140-200 ppm for granular sizes between 1.0-0.2 mm in diameter thus, the uranium loading kinetics for the resin is faster than for hydrous titanium oxide (Fig. 7). A further increase of the rate of uranium uptake could be achieved by using fibers of poly(acrylamidoxime) instead of granules uranium loadings of 750 ppm were obtained in natural sea water after ten days. 

Fig. 8. Uranium uptake of poly(acrylamid-oxime) granules from sea water in a fluidized bed in dependence on time and granular size155 ...

Moyes LN, Parkman RH, Chamock JM, Vaughan DJ, Livens FR, Hughes CR, Braithwaite A (2000) Uranium uptake from aqueous solution by interaction with goethite, lepidocrocite, muscovite, and mackinawaite An X-ray absorption spectroscopy study. Environ Sci Technol 34 1062-1068 Muller F, Besson G, Manceau A, Drits V-A (1997) Distribution of isomorphous cations within octahedral sheets in montmorillonite from Camp-Bertaux. Phys Chem Minerals 24 159-166 Muller J-P, Manceau A, Calas G, Allard T, Ildefonse P, Hazemann, J-L (1995) Crystal chemistry of kaolinite and Fe-Mn oxides relation with formation conditions of low temperature systems. Am J Sci 295 1115-1155... 

Middleton J (1844) On the flourine in bones, its source and its application to the deterniination of the geological age of fossil bones. Proc Geol Soc London 4 148-157 Millard AR (1993) Diagenesis of archaeological bone The case of uranium uptake. PhD dissertation, Univ Oxford, Oxford, UK... 

K. Sekiguchi, K. Serizawa, S. Konishi, K. Saito, S. Furusaki andT. Sugo, Uranium Uptake during Permeation of Seawater through Amidoxime-Group-Immobilized Micropores, Reactive Polym., 23 (1994) 141. 

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