Results 171 to 180 of about 19,368 (228)
Some of the next articles are maybe not open access.
Industrial & Engineering Chemistry, 1961
A laboratory scale chlorination of Egyptian monazite sand concentrate was carried out at 900 deg C in a horizontal tube furnace, and the variables affecting the condensation and purity of the thorium chloride produced were studied. In 30 minutes, 97.8% of the monazite content was attacked.
O. M. Hilal, F. A. El. Gohary
openaire +1 more source
A laboratory scale chlorination of Egyptian monazite sand concentrate was carried out at 900 deg C in a horizontal tube furnace, and the variables affecting the condensation and purity of the thorium chloride produced were studied. In 30 minutes, 97.8% of the monazite content was attacked.
O. M. Hilal, F. A. El. Gohary
openaire +1 more source
Chemical Geology, 2008
Abstract Diffusion of Th has been characterized in synthetic monazite under dry conditions. The synthetic monazites (either pure CePO4, NdPO4, or a mixed LREE phosphate containing Ce, Nd, and Sm) were grown via a Na2CO3–MoO3 flux method. The sources of diffusant for the experiments were either synthesized ThSiO4 or CaTh(PO4)2 powders mixed with CePO4.
D.J. Cherniak, J.M. Pyle
openaire +1 more source
Abstract Diffusion of Th has been characterized in synthetic monazite under dry conditions. The synthetic monazites (either pure CePO4, NdPO4, or a mixed LREE phosphate containing Ce, Nd, and Sm) were grown via a Na2CO3–MoO3 flux method. The sources of diffusant for the experiments were either synthesized ThSiO4 or CaTh(PO4)2 powders mixed with CePO4.
D.J. Cherniak, J.M. Pyle
openaire +1 more source
Nature, 1948
X-RAY examination of monazite has been carried out by Hadding1, Gliszczynski2 and Parrish3, and the space group and crystal class uniquely determined. According to Goldschmidt4, the thorium which is usually present is ‘‘captured during crystallization of the phosphate from its parent magma because of its favourable ionic size.
openaire +1 more source
X-RAY examination of monazite has been carried out by Hadding1, Gliszczynski2 and Parrish3, and the space group and crystal class uniquely determined. According to Goldschmidt4, the thorium which is usually present is ‘‘captured during crystallization of the phosphate from its parent magma because of its favourable ionic size.
openaire +1 more source
Geochimica et Cosmochimica Acta, 1997
Abstract We have measured the tracer diffusion rate of Pb in natural, annealed, gem-quality monazite from Alexander Co., NC, USA, and Riverside Co., CA, USA. Observations from the literature concerning low T annealing in monazite suggest the possibility that Pb diffusion at geologic conditions occurs, in effect, within a similarly annealed lattice ...
Harold A. Smith, Bruno J. Giletti
openaire +1 more source
Abstract We have measured the tracer diffusion rate of Pb in natural, annealed, gem-quality monazite from Alexander Co., NC, USA, and Riverside Co., CA, USA. Observations from the literature concerning low T annealing in monazite suggest the possibility that Pb diffusion at geologic conditions occurs, in effect, within a similarly annealed lattice ...
Harold A. Smith, Bruno J. Giletti
openaire +1 more source
Controlled leaching of monazites
Journal of Geophysical Research, 1967The difficulties of obtaining a clear-cut geological interpretation of calculated isotopic ages are often increased by the presence of discordant age patterns. Although such patterns have been reported for most uranium-thorium bearing minerals, age determinations on monazites may exhibit distinctly more pronounced discrepancies.
A. J. Burger +2 more
openaire +1 more source
Earth and Planetary Science Letters, 2004
Abstract We report measurements of oxygen diffusion in natural monazites under both dry, 1-atm conditions and hydrothermal conditions. For dry experiments, 18O-enriched CePO4 powder and monazite crystals were sealed in Ag–Pd capsules with a solid buffer (to buffer at NNO) and annealed in 1-atm furnaces.
D.J. Cherniak +3 more
openaire +1 more source
Abstract We report measurements of oxygen diffusion in natural monazites under both dry, 1-atm conditions and hydrothermal conditions. For dry experiments, 18O-enriched CePO4 powder and monazite crystals were sealed in Ag–Pd capsules with a solid buffer (to buffer at NNO) and annealed in 1-atm furnaces.
D.J. Cherniak +3 more
openaire +1 more source
Deformation twinning in monazite
Acta Materialia, 2003Abstract Polycrystalline monazite (LaPO4) was deformed at room temperature by a spherical indenter. Deformation twins were identified by TEM in 70 grains. Five twin planes were found: (1 0 0) was by far the most common; (0 0 1) and (1 2 0) were less common; ( 1 2 2 ) was rare, and kinks in (1 2 0) twins were identified as irrational ′(
R.S Hay, D.B Marshall
openaire +1 more source