Cerium-activated rare-earth orthophosphate and double-phosphate scintillators for x- and gamma-ray detection

2004 ◽  
Author(s):  
Lynn A. Boatner ◽  
L. A. Keefer ◽  
J. M. Farmer ◽  
Dariusz Wisniewski ◽  
Andrjez J. Wojtowicz
Keyword(s):  
Rare Earth ◽  
Gamma Ray ◽  
Double Phosphate

Cerium-doped mixed-alkali rare-earth double-phosphate scintillators for x- and gamma-ray detection

2006 ◽  
Author(s):  
John S. Neal ◽  
Lynn A. Boatner ◽  
Merry Spurrier ◽  
Piotr Szupryczynski ◽  
Charles L. Melcher
Keyword(s):  
Rare Earth ◽  
Gamma Ray ◽  
Mixed Alkali ◽  
Double Phosphate

Rare-earth tri-halides methanol-adduct single-crystal scintillators for gamma ray and neutron detection

2009 ◽  
Author(s):  
L. A. Boatner ◽  
D. J. Wisniewski ◽  
J. S. Neal ◽  
Z. W. Bell ◽  
J. O. Ramey ◽  
...  
Keyword(s):  
Rare Earth ◽  
Single Crystal ◽  
Gamma Ray ◽  
Neutron Detection

Radioelement distribution in U, Th, Mo, and rare-earth-element pegmatites, skarns, and veins in a portion of the Grenville Province, Ontario and Quebec

1991 ◽  
Vol 28 (1) ◽  
pp. 1-12 ◽  
Author(s):  
David Lentz
Keyword(s):  
Rare Earth ◽  
Rare Earth Element ◽  
Earth Element ◽  
Gamma Ray ◽  
Grenville Province ◽  
Heterogeneous Distribution ◽  
Granitic Pegmatites ◽  
Gamma Ray Spectrometer ◽  
Calcite Veins ◽  
Secondary Enrichment

Gamma-ray spectrometer measurements were obtained at and in the vicinity of 104 of the 124 U, Th, Mo, and rare-earth-element (REE) occurrences examined in the Central Metasedimentary Belt of the Grenville Province. Spatial, temporal, mineralogical, and geochemical relationships among granitic pegmatites, phlogopite – scapolite – Ca pyroxene skarns, and fluorite – apatite – calcite veins hosting U, Th, Mo, and REE minerals indicate a common magmatic–hydrothermal origin. Quartz–feldspar gneisses in the Central Metasedimentary Belt (n = 54) have low abundances of uranium (1–7 ppm) and thorium (4–27 ppm) suggesting that partial melting, fractional crystallization, and volatile phase separation were responsible for the enrichment of uranium (2–37 ppm) and thorium (5–102 ppm) in uncontaminated granitic pegmatites (n = 163) derived during ultrametamorphism. The U/Th ratio is probably inherited from the source quartz–feldspar gneiss protolith and enhanced during fractionation.Average U and Th concentrations and U/Th ratios at numerous localities show significant positive correlations among pegmatites, skarns, and veins, providing further evidence for a related origin. The interaction of the pegmatite-derived hydrothermal fluids with host rocks produced a spectrum of types and styles of alteration, which include (i) hybridization and (or) endoskarnification along pegmatite margins; (ii) marble- and clinopyroxenite-hosted exoskarn; and (iii) fluorite–apatite–calcite veins. The deposition of U, Th, Mo, and REE from the evolving hydrothermal fluid is responsible for the heterogeneous distribution of U, Th, and REE minerals and molybdenite within pegmatites, skarns, and veins at each locality. Secondary enrichment of uranium in association with hematitized sheared pegmatites and veins may be responsible for the observed large variation in U/Th ratios at some sites.

Gamma-Ray Thermoluminescence in Rare-Earth-Activated Y2O3Phosphors

1968 ◽  
Vol 7 (12) ◽  
pp. 1497-1503 ◽  
Author(s):  
Yasuro Ato ◽  
Ryoitiro Huzimura ◽  
Lyuji Ozawa
Keyword(s):  
Rare Earth ◽  
Gamma Ray

Luminescence characterization of gamma-ray-irradiated rare-earth doped BaSO4 and MgSO4 phosphors

2011 ◽  
Vol 46 (12) ◽  
pp. 1372-1375 ◽  
Author(s):  
R.S. Kher ◽  
A.K. Upadhyay ◽  
S.K. Gupta ◽  
S.J. Dhoble ◽  
M.S.K. Khokhar
Keyword(s):  
Rare Earth ◽  
Gamma Ray ◽  
Rare Earth Doped

scholarly journals Some Aspects of the Geochemistry and Natural Radioactivity of the Azov Deposit Ores

2021 ◽  
pp. 25-35
Author(s):  
E.М. Sheremet ◽  
◽  
I.Yu. Nikolaev ◽  
L.D. Sietaia ◽  
S.М. Strekozov ◽  
...  
Keyword(s):  
Rare Earth ◽  
Natural Radioactivity ◽  
Gamma Ray ◽  
Specific Activity ◽  
Gamma Activity ◽  
Zro2 Content ◽  
Γ Radiation ◽  
Processing And Storage ◽  
And Storage ◽  
Enclosing Rocks

The analysis of the Azov deposit of zirconium-rare earth ores as the object capable on qualitative and quantitative parameters to become key for creation and modernization of rare earth subsectors of the industry of Ukraine is carried out. On the basis of the generalized characteristics of zirconium-rare earth mineralization, conclusions were drawn regarding the nature of the increased radioactivity at the Azov deposit, which is mainly due to the presence of certain minerals in the ores. The actual radioactive minerals were found only as inclusions in zircon and do not make a significant contribution to the natural radioactivity of ores. It has been established that the radioactivity is uranium-thorium due to the inclusion of these elements in the composition of the aforementioned minerals. The results of the radiation-hygienic assessment of core samples from the deposit are presented. According to the existing standards, the enclosing rocks of the supra-ore and under-ore strata can be used in all types of construction without restrictions. The ores of the deposit are assigned to the third class in terms of the level of effective specific activity. It was found that there is a significant direct relationship between gamma activity and the total REE content in the field. There is also a correlation between the content of U and Th, the dose rate of γ-radiation and the content of the total REE. It was shown that there is no relationship between these indicators and the ZrO2 content. Analysis of the gamma-ray logs showed the possibility of confidently drawing the boundaries of the ore intervals and fixing the inter-ore intervals. The main stages of the technological process of integrated development, enrichment, processing and storage of enrichment tailings, slags and sludge, which ensure the minimum impact of production on the environment and human health, have been determined.

Sign in / Sign up

Export Citation Format

Share Document