The process of gas generation for radium sources embedded in metal matrices (or metal capsules) is described in order to obtain the conditions of safe immobilisation of radium sources in metal matrices. For this purpose a simple model describing immobilisation of sources in a metal housing is proposed. Both helium and radon generation is considered near a radium source. Partial pressures of hel...

The vertical activity concentration distributions of the radium isotopes, 226 Ra and 228 Ra, which are useful as radiotracers, were obtained for first time in western Subarctic Pacific Gyre (WSAG). It was possible to detect short-lived present from surface 400 m depth by analyzing large seawater samples. Low high concentrations layer WSAG strongly influenced upwelled deeper water with nutrients...

Radium needles that were once implanted into tumours as a cancer treatment are now obsolete and constitute a radioactive waste problem, as their half-life is 1600 years. We are investigating the reduction of radium by transmutation on a small scale by bombarding Ra-226 with high-energy photons from a medical linear accelerator (linac) to produce Ra-225, which subsequently decays to Ac-225, whic...

This paper is a survey of recent results concerning connections between relation algebras (RA), cylindric algebras (CA) and polyadic equality algebras (PEA). We describe exactly which subsets of the standard axioms for RA are needed for axiomatizing RA over the RA-reducts of CA3’s, and we do the same for the class SA of semi-associative relation algebras. We also characterize the class of RA-re...

Assessment of any release of radioactivity to the environment is important for the protection of public health, especially if the released radioactivity can enter the food chain. In the present work, a pot experiment carried out in greenhouse in Qassim University in order to examine the effect of contaminated irrigation water on migration and retention of radioactive elements in soil and plants...

a r t i c l e i n f o The fate of terrigenous dissolved organic carbon (tDOC) delivered to the Arctic Ocean by rivers remains poorly constrained on both spatial and temporal scales. Early reports suggested Arctic tDOC was refractory to degradation, while recent studies have shown tDOC removal to be an active but slow process. Here we present observations of DOC, salinity, δ 18 O, and 228 Ra/ 22...

a r t i c l e i n f o Keywords: silica-undersaturated volcanism 238 U-230 Th-226 Ra-210 Pb series disequilibria magma transport and residence time carbonate metasomatism volcanic hazard assessment The silica-undersaturated Nyiragongo volcanics, located in the East African Rift, have globally unique chemical compositions and unusually low viscosities, only higher than carbonatite lavas, for terr...

Abstract Soil and sand samples were collected from eight different locations in the Al-Dakhiliya governorate, Sultanate of Oman to determine evaluate natural artificial radioactivity levels. The activity concentrations radionuclides 137 Cs, 226 Ra, 40 K, 235 U 228 Ac measured using high resolution gamma-ray spectroscopy detectors (HPGe detectors). In addition, radiation hazard indexes evaluated...

The activity concentrations of (226)Ra, (232)Th and (40)K in seven brands of Portland cement used in Nigeria have been determined using a gamma-ray spectrometer with a hyperpure germanium detector. A total of 22 samples were collected from suppliers. The mean activity concentrations varied between 19.2 and 85.1 Bq kg(-1), 12.9 and 31.7 Bq kg(-1), and 31.5 and 116 Bq kg(-1) for (226)Ra, (232)Th ...