Synchrotron X-rays have been used to study the oxidation of uranium and uranium hydride when encapsulated in grout and stored in de-ionised water for 10 months. Periodic synchrotron X-ray tomography and X-ray powder diffraction have allowed measurement and identification of the arising corrosion products and the rates of corrosion. The oxidation rates of the uranium metal and uranium hydride we...

Understanding which organisms are capable of reducing uranium at historically contaminated sites provides crucial information needed to evaluate treatment options and outcomes. One approach is determination of the bacteria which directly respond to uranium addition. In this study, uranium amendments were made to groundwater samples from a site of ongoing biostimulation with acetate. The active ...

Diffusion behaviours of oxygen and uranium were evaluated for bulk and grainboundaries of uranium dioxide using the molecular dynamics (MD) simulation. It elucidated that oxygen behaved like liquid in superionic state at high temperatures and migrated on sublattice sites accompanying formation of lattice defects such as Frenkel defects at middle temperatures. Formation energies of Frenkel and S...

The main aim of this study was to determine and evaluate urinary excretion values of uranium in occupationally unexposed subjects from Nigeria. As several uranium mines are running in Nigeria and the operations could be a risk of contamination for the workers as well as for the members of the public, biomonitoring of urine could provide information about the exposure to uranium for the subjects...

SRTC evaluated the feasibility of using the H Canyon on-line diode array spectrophotometer to measure uranium concentrations in Tank 16.7. On-line measurements will allow an increase in highly enriched uranium (HEU) production by removing delays associated with off-line measurements. The instrument must be able to measure uranium at concentrations below 1.0 g/L with an uncertainty no greater th...

The dissolution of uranium was investigated from contaminated sediments obtained at the US. Department of Energy (U.S. DOE) Hanford site. The uranium existed in the sediments as uranyl silicate microprecipitates in fractures, cleavages, and cavities within sediment grains. Uranium dissolution was studied in Na, Na-Ca, and NH4 electrolytes with pH ranging from 7.0 to 9.5 under ambient CO2 pressu...

In situ leaching of uranium ores with sulfuric acid during active uranium mining activity on the Gessenheap has caused longstanding environmental problems of acid mine drainage and elevated concentrations of uranium. To study there remediation measures the test site Gessenwiese, a recultivated former uranium mining heap near Ronnenburg/East Thuringia/Germany, was installed as a part of a resear...

At one hand uranium is an element of considerable technological importance. In nuclear power plants uranium is used as fuel. Other than this, uranium has no significant commercial use. On the other hand uranium is highly toxic and radioactive heavy metal that mainly originates from nuclear-related activities and causes significant environmental and public health problems by its presence in terr...

In the face of depletion of fossil resources, the development of nuclear power in the world is inevitable. Poland is one of the few developed countries, which does not have a nuclear power plant [1]. Therefore, The programme of Polish nuclear energy has recently been implemented. Simultaneously, the interest in domestic uranium ores, which fi rst appeared in the fi ftieth of the previous centur...

The goal of this work is a detailed study of uranium detection by laser-induced breakdown spectroscopy (LIBS) for application to activities associated with environmental surveillance and detecting weapons of mass destruction (WMD). The study was used to assist development of LIBS instruments for standoff detection of bulk radiological and nuclear materials and these materials distributed as con...