All Outputs (115)

Quantification of the effects of pore clogging in potential PRB substrates using image analysis (2005)
Journal Article

Permeable reactive barriers (PRBs) have demonstrated a promising approach for groundwater remediation. However, one concern is the deterioration of barrier material performance due to mineral precipitation and pore clogging. This study sought to quan... Read More about Quantification of the effects of pore clogging in potential PRB substrates using image analysis.

Suitability testing of selected wastes and natural substrates for permeable reactive barriers (PRBs) (2005)
Journal Article

Performance of barrier materials is important for the long-term success of permeable reactive barriers (PRBs). A number of selected wastes and natural materials were tested in batch experiments for their ability to remove heavy metals from synthetic... Read More about Suitability testing of selected wastes and natural substrates for permeable reactive barriers (PRBs).

The geochemistry of fluids from an active shallow submarine hydrothermal system: Milos island, Hellenic Volcanic Arc (2005)
Journal Article

Geothermal activity in the Aegean island of Milos (Greece), associated with island-arc volcanism, is abundant both on-and off-shore. Hydrothermal fluids venting from several sites, mainly shallow submarine (up to 10 m), but also just above seawater l... Read More about The geochemistry of fluids from an active shallow submarine hydrothermal system: Milos island, Hellenic Volcanic Arc.

Natural and waste materials as metal sorbents in permeable reactive barriers (PRBs) (2005)
Journal Article

A range of waste products and natural materials including chitin, fly ash, clay soil, cocoa shell, calcified seaweed and the natural zeolite clinoptilolite were tested in batch experiments to assess their ability to remove metals from a synthetic gro... Read More about Natural and waste materials as metal sorbents in permeable reactive barriers (PRBs).

Time-dependent surface reactivity of Cd sorbed on calcite, hydroxylapatite and humic acid (2005)
Journal Article

Changes in the lability and local environment of Cd sorbed onto calcite, hydroxylapatite and humic acid have been investigated as a function of time (30 min-9 months) using a combination of X-ray adsorption spectroscopy (XAS) and isotopic dilution te... Read More about Time-dependent surface reactivity of Cd sorbed on calcite, hydroxylapatite and humic acid.

Uranyl-citrate speciation in acidic aqueous solutions - An XAS study between 25 and 200 °C (2004)
Journal Article

Speciation of uranium(VI) in citrate (2-hydroxypropane-1,2, 3-tricarboxylic acid) solutions between 25 and 200 °C, at pH values between 0.8 and 3.7 and at citrate/U ratios between 0.5 and 50 has been investigated using U LIII-edge X-ray absorption sp... Read More about Uranyl-citrate speciation in acidic aqueous solutions - An XAS study between 25 and 200 °C.

Uranyl acetate speciation in aqueous solutions-An XAS study between 25°C and 250°C (2004)
Journal Article

Speciation of uranium (VI) in acetate solutions between 25 and 250°C, at pH values between 1.8 and 3.8 and acetate/uranium (Ac/U) ratios of 0.5 to 100 has been investigated using uranium LIII-edge X-ray absorption spectroscopy. With increasing pH the... Read More about Uranyl acetate speciation in aqueous solutions-An XAS study between 25°C and 250°C.

Uranium biosorption by the lichen trapelia involuta at a uranium mine (2004)
Journal Article

Metal localisation was investigated in the lichenised ascomycete Trapelia involuta growing on a range of uraniferous minerals including metazeunerite [Cu(UO2)2(AsO42·8H2O], metatorbernite [Cu(UO22(PO4)2·8H2O], autunite [Ca(UO2)2(PO42·10H2O] and urani... Read More about Uranium biosorption by the lichen trapelia involuta at a uranium mine.

Predicting arsenic solubility in contaminated soils using isotopic dilution techniques (2002)
Journal Article

An isotopic dilution assay was developed to measure radiolabile As concentration in a diverse range of soils (pH 3.30-7.62; % C = 1.00-6.55). Soils amended with 50 mg of As kg-1 (as Na2HAsO4·7H2O) were incubated for over 800 d in an aerated "microcos... Read More about Predicting arsenic solubility in contaminated soils using isotopic dilution techniques.

A study of uranium speciation in acetate solutions at temperatures from 25 to 250°C (2001)
Journal Article

We report U L3-edge XAS analysis results from a study of the speciation of U(VI) in acetate solutions between 25 and 250°C, at pH's between 1.82 and 2.57 and [acetate]:[U] ratios of 0.5 to 50. At 25°C in excess acetate there are at least two acetate... Read More about A study of uranium speciation in acetate solutions at temperatures from 25 to 250°C.

Hydrothermal sediments associated with a relict back-arc spreading center in the Shikoku Basin, recovered from the Nankai accretionary prism, Japan (1999)
Journal Article

The hemipelagic mudrocks of the Nankai accretionary prism, Japan, contain hydrothermal deposits associated with a relict spreading center in the Shikoku Basin. Initial work on core samples from Ocean Drilling Program site 808 found several samples wi... Read More about Hydrothermal sediments associated with a relict back-arc spreading center in the Shikoku Basin, recovered from the Nankai accretionary prism, Japan.

Bioaccumulation of metals by lichens: Uptake of aqueous uranium by Peltigera membranacea as a function of time and pH (1998)
Journal Article

Uranium sorption experiments were carried out at ∼25 °C using natural samples of the lichen Peltigera membranacea. Thalli were incubated in solutions containing 100 ppm U for up to 24 h at pH values from 2 to 10. Equilibrium sorption was not observed... Read More about Bioaccumulation of metals by lichens: Uptake of aqueous uranium by Peltigera membranacea as a function of time and pH.

Role for lichen melanins in uranium remediation (1998)
Journal Article

Lichens are successful colonizers in extreme terrestrial habitats world-wide, including metalliferous environments1. Their ability to accumulate metals has led to their use in monitoring radionuclide fall-out from Chernobyl and uranium uptake from du... Read More about Role for lichen melanins in uranium remediation.

Uranium and thorium solubilities in subduction zone fluids (1994)
Journal Article

Uranium is enriched in depleted island arc magmas more than would be anticipated, due to the overall enrichment in large ion lithophile elements. To attempt to understand this enrichment calculations were performed to establish concentrations of uran... Read More about Uranium and thorium solubilities in subduction zone fluids.

Determination of uranium and thorium in basalts and uranium in aqueous solution by inductively coupled plasma mass spectrometry (1993)
Journal Article

Methods are described for the simultaneous determination of uranium and thorium in basaltic rocks at concentrations from mg kg-1 (ppm) to ?g kg-1 (ppb) levels and for uranium in solution at femtogram levels. The technique for basalts does not require... Read More about Determination of uranium and thorium in basalts and uranium in aqueous solution by inductively coupled plasma mass spectrometry.