Geochemical studies of rare earth elements (REEs) as well major and trace were conducted on the beach placer sands from Kanyakumari coastal region, a well-known high background natural radiation area (HBNRA). For first time, uranium isotope ratios (234U/238U 235U/238U) determined in study to investigate provenance leaching U sands. Inductively coupled plasma mass spectrometry was used for measu...

An analytical exercise was initiated in order to determine those procedures with the capability to measure total uranium and uranium (238U/235U) isotopic ratios in urine samples containing >0.02 microg U kg-1 urine. A host laboratory prepared six identical sets of twelve synthetic urine samples containing total uranium in the range of 25 to 770 ng U kg-1 urine and with 238U/235U isotopic ratios...

A method for the determination of uranium and 210Po in high salinity water samples has been elaborated. Both radionuclides are preconcentrated from 0.5 dm3 saline media by co-precipitation with hydrated manganese dioxide, followed by dissolution of the precipitate in 200 mL of 1 M HCl. Uranium isotopes 235U and 238U can be directly determined by ICP MS method with a detection limit of 0.01 ppb ...

Speleothem initial uranium isotope ratios ((234U/238U)i) can be influenced by processes along the seepage water flow-path including alpha-recoil into porewater during 238U decay and hostrock weathering, balance of which reflect infiltration rate. Thus, speleothem (234U/238U)i may provide information about past changes in rainfall amounts. However, utility as a paleo-infiltration proxy has only ...

Phosphogypsum (PG) is a residue of the phosphate fertilizer industry that has relatively high concentrations of harmful radioactive materials. The reduction in concentration of the radionuclides from PG was investigated. The removal process is based on leaching of radionuclides using suitable organic extractants. The studied radionuclides were 226Ra, 210Pb, 238U and 40K. The factors affect the ...

Naturally occurring radioactive materials (NORMS) and fallout 137Cs were estimated in surface soils from the highly mineralized Singhbhum region of Eastern India. The activity concentrations varied from 50.67-109.14 Bq/kg (238U), 48.12142.55 Bq/kg (226Ra), 28.73-89.78 Bq/kg (232Th), 494.84-1121.36 Bq/kg (40K) and 1.8-7.48 Bq/kg (137Cs). Correlation between radionuclides was studied. 232Th/238U ...

We report the 238U-23øTh agederived from samples from three basalt flows from the Albuquerque Volcanoes Field, central New Mexico (USA), interpreted to have erupted during one of the Bruhnes Chron geomagnetic field polarity events. Whole-rock samples and magnetite separates from two of the samples define an isochron with an age of 156 + 29 ka (2o). It is now possible to determine the ages of ge...

Soil samples from three major towns and a holiday settlement in uranium-rich western Namibia have been analysed using a HPGe detector for radioactivity due to 238U, 232Th and 40K. The average activity concentrations of the radionuclides in the towns and settlement vary from a low of 18.6 ± 4.6 to a high of 69.6 ± 26.3 Bq kg−1 for 238U, 23.8 ± 8.4 to 91.1 ± 41.0 Bq kg−1 for 232Th and 460.3 ± 76....

Abstract. We describe a new method for the measurement of U/Pb ratios by isotope dilution multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) dating geologically young clean carbonates, particularly speleothems. The is intended materials containing little or no initial 232Th. illustrate and validate with four examples ranging from 0.57 to 20 Ma. capable applying 235U–207Pb ...

Secondary reactions induced by relativistic beams in inverse kinematics in a thick target are relevant in several fields of experimental physics and technology, like secondary radioactive beams, production of exotic nuclei close to the proton drip line, and cross-section measurements for applications of spallation reactions for energy production and incineration of nuclear wastes. A general mat...