Rare earth element distribution

De Baar, H.J.W., German, C.R., Elderfield, H. and Van Gaans, P. (1988) Rare earth element distributions in anoxic waters of the Cariaco Trench. Geochim. Cosmochim. Acta, 52, 1203-1219. 

Rare Earth Element Distribution Patterns to Characterize Soapstone Artifacts... 

Elphic R. C., Lawrence D. J., Feldman W. C., Barraclough B. L., Maurice S., Binder A. B., and Lucey P. G. (2000) Lunar rare earth element distribution and ramifications for FeO and Ti02 Lunar Prospector neutron spectrometer observations. J. Geophys. Res. 105, 20333-20345. 

All values are on a coal basis. Data are exclusively from the US Geological Survey (USGS) except for estimated values in parenthesis which are based on USGS and literature data. Values in brackets are calculated from cerium and lanthanum data and assuming a chondrite normalized rare-earth-element distribution pattern. (ND — no data SD — standard deviation Max. — maximnm Num. = nnmber of samples). 

Rakovan J, Reeder RJ (1994) Differential incorporation of trace elements and dissymmetrization in apatite The role of surface structure during growth. Am Mineral 79 892-903 Rakovan J, Reeder RJ (1996) Intraciystalline rare earth element distributions in apatite ... 

Allen RO, Pennell SE (1978) Rare Earth Element Distribution Patterns to Characterize Soapstone Artifacts, in Archaeological Chemistry II, (ed. Carter OF) p. 230, Washington, D.C., American Chemical Society... 

The method of luminescent spectroscopy is widely used to study the rare-earth elements distribution in natural scheelite (Brugger et al. 2000). Comparisons with synthetic pure and doped phosphors showed that W04 are responsible for blue emission in scheelite (Tiede and Schleede, quoted in Pringsheim and Vogel 1946). 

Brenier A, Suchocki A, Pedrini C, Boulon G, Made C (1992) Spectroscopy of Mn -doped calcium-substituted gadolinium gallium garnet. Phys Rev B 46 3219-3227 Brugger J, Bettiol A, Costa S et al (2000) Mapping rare earth element distribution in scheelite using luminescence. Miner Mag 64 891-903... 

Liquid—Liquid Extraction. The tiquid—tiquid extraction process for the rare-earth separation was discovered by Fischer (14). Extraction of REE using an alcohol, ether, or ketone gives separation factors of up to 1.5. The selectivity of the distribution of two rare-earth elements, REI and RE2, between two nonmiscible tiquid phases is given by the ratio of the distribution coefficients DI and D2 ... 

Bence, A.E. (1983) Volcanogenic massive sulfides rtx k/water interactions in ba.saltic systems and their effects on the distribution of the rare earth elements and selected first. series transition elements (abst.). 4th International Symposium on Water-Rock interaction, Mi.sasa, Japan, 48. 

Geological, mineralogical and geochemical features of these deposit types (distribution, age, associated volcanism, host and country rocks, fluid inclusions, opaque, gangue and hydrothermal alteration minerals, chemical features of ore fluids (temperature, salinity, pH, chemical composition, gaseous fugacity, isotopic compositions (O, D, S, Sr/ Sr, Pb), rare earth elements)) were summarized. 

Moskalev, Yu.I., Zalinkin, G. A. and Stephanov, V. S. (1970). Distribution Patterns for Radioactive Rare-Earth Elements, Report No. ANL-Trans-832 (Argonne National Laboratory, Argonne, Illinois). 

Bau M, Dulski P (1996) Distribution of yttrium and rare-earth elements in the Penge and Kuruman iron-formations, Transvaal Supergroup, South Africa. Precam Res 79 37-55 Bau M, Hohndorf A, Dulski P, Beukes NJ (1997) Sources of rare-earth elements and iron in Paleoproterozoic iron-formations from the Transvaal Supergroup, South Africa evidence from neodymium isotopes. J Geol 105 121-129... 

Table 10.1 lists r values calculated for normalized distributions of alkalis and alkaline earths between silicates and hydrothermal solutions and for normalized distributions of rare earth elements (REE) between pyroxenes and silicate melts. 

Copper, Ni, Re, the rare earth elements (REE), and Tl exhibit similar distributions with the upper quartile of data from samples centred about Pebble West. These elements occur in ponds, springs, and borehole seeps, but are highest in the low-pH ponds. Curiously, elevated values of Cu and REE are not present in borehole seeps (circum-neutral pH). 

McKenzie, D. and O Nions, R.K., 1991. Partial melt distributions from inversion of rare earth element concentrations. J. Petrol., 32 1021-1091. 

Carbide cluster ions (MC + - M = matrix element) have been measured by investigating them directly from the solid carbides (B4C,46 SiC) or by analyzing metal oxide/graphite mixtures (for M = rare earth element,3 Si,46 Th or U36). Figure 9.60 shows the distribution of silicon carbide cluster ions (SiC +) in laser ionization mass spectrometry by the direct analysis of compact SiC in comparison to the carbide cluster ion distribution of LaC + and SrC + in spark source mass spectrometry, by investigating a metal oxide/graphite mixture. 

As reported by Olmez and Gordon (University of Maryland), the concentration pattern of rare earth elements on fine airborne particles (less than 2.5 micrometers in diameter) is distorted from the crustal abundance pattern in areas influenced by emissions from oil-fired plants and refineries. The ratio of lanthanum (La) to samarium (Sm) is often greater than 20 (crustal ratio is less than 6). The unusual pattern apparently results from tlie distribution of rare earths in zeolite catalysts used in refining oil. Oil industry emissions have been found to perturb the rare earth pattern even in very remote locations, such as the Mauna Loa Observatory in Hawaii. 

Ravichandran, M. (1996) Distribution of rare Earth elements in sediment cores of Sabine-Neches estuary. Mar. Pollut. Bull. 32, 719-726. 

The position of Ba in the periodic system just before the rare earth elements indicates that the electronic charge distribution in the outermost region will be very sensitive to changes in the effective nuclear charge. Previously, in Sect. 6.1, we studied the effect of collapse of the 4f-orbital on the behaviour of 4 s and 4p holes. In this section we shall investigate the effect of collapse of the 5d-shell, as already briefly discussed in Section 3.4 (see also1073). 

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