This paper presents the results of determination of activity concentration of 238U and 234U in urine samples of people living in Warsaw (capital of Poland) to evaluate background level of these radionuclides excretion rate (mBq day-1). The samples were taken from women and men in age between 3 and 97 years. The results obtained for 238U daily excretion rate were in range 0.44-30.54 mBq day-1 an...

Neutron-induced fission cross sections of 238U and 235U are used as standards in the fast neutron region up to 200 MeV. A high accuracy of the standards is relevant to experimentally determine other neutron reaction cross sections. Therefore, the detection efficiency should be corrected by using the angular distribution of the fission fragments (FFAD), which are barely known above 20 MeV. In ad...

In the present study, 137Cs and 238U activity concentrations, 234U/238U ratio, 235U/238U isotope ratio were measured in fifteen soil samples collected from exclusion zone around Fukushima Daiichi Nuclear Power Station (FDNPS). The concentrations of Fukushima-accident contaminated ranged 29.9 to 4780 kBq kg−1 with a mean 2007 kg−1. On other hand, these 5.2 22.4 Bq 13.2 ratios 0.973 1.023. varied...

Background: Assessment of activity concentrations of 238U, 232Th, 40K and gamma dose rate (DR) was carried out over a laterite mining field in Ilorin-south, Nigeria. Materials and Methods: A well calibrated Super-Spec (RS-125) gamma spectrometer was used to measure the activity concentrations of 40K, 238U, 232Th and gamma doses rate at 1 m above the ground level over the laterite mining field. ...

Compositions of arc magmas depend on several factors and are often thought to reflect conditions in the mantle wedge at slab-mantle interface. However, continental settings, also influenced by assimilation crust. Here, we present measurements modeling 238U-230Th activity ratios, Sr, Nd, Hf, Pb isotopic compositions, major trace element concentrations young, historic lavas erupted from Reventado...

Uranium isotope ratios are widely utilized in paleoceanography. The 238U/235U ratio (expressed as ?238U) is leveraged a proxy for the areal extent of anoxic seafloor, and 234U/238U ?234Usec) tracks riverine estuarine inputs to ocean, addition featuring prominently U-series geochronology. Both these thought be recorded by biological carbonates precipitating from seawater, with corals serving one...

Uranium isotopes have been used as mechanistic or time scale tracers of natural processes. This paper describes the occurrence and redistribution of U in the Vendian aquifer of a paleo-valley in NW Russia. Forty-four rock samples were collected from nine boreholes with depths up to 160 m, and 25 groundwater samples were collected from 23 boreholes with depths up to 300 m. The U, Fe concentratio...

Natural waters universally show fractionation of uranium series (U-series) parent–daughter pairs, with the disequilibrium between U and U (U)/(U) commonly used as a tracer of groundwater flow. Because speleothems provide a temporal record of geochemical variations in groundwater precipitating calcite, (U)/(U) variations in speleothems provide a unique method of investigating water–rock interact...