A5067365658- Nuclear materials and radiation effects
- Radioactive element chemistry and processing
- Nuclear Materials and Properties
- Advanced Condensed Matter Physics
- Geological and Geochemical Analysis
- Ferroelectric and Piezoelectric Materials
- Microwave Dielectric Ceramics Synthesis
- High-pressure geophysics and materials
- Electronic and Structural Properties of Oxides
- Luminescence Properties of Advanced Materials
- Ion-surface interactions and analysis
- Crystal Structures and Properties
- Astro and Planetary Science
- Glass properties and applications
- Chemical Synthesis and Characterization
- Geochemistry and Geologic Mapping
- Fusion materials and technologies
- Intermetallics and Advanced Alloy Properties
- Mineralogy and Gemology Studies
- Semiconductor materials and devices
- X-ray Diffraction in Crystallography
- High Entropy Alloys Studies
- Nuclear Physics and Applications
- Advanced ceramic materials synthesis
- Inorganic Chemistry and Materials
Australian Nuclear Science and Technology Organisation
2013-2022
Australian Government
2019-2020
University of Cambridge
2003-2018
Argonne National Laboratory
2008
University of St Andrews
2006
Australian Institute of Nuclear Science and Engineering
2005
University of New Mexico
1984-1991
University of California, Berkeley
1980-1983
Virginia Tech
1979
A natural single crystal of zircon, ZrSiO(4,) from Sri Lanka exhibited zonation due to alpha-decay damage. The zones vary in thickness on a scale one hundreds micrometers. uranium and thorium concentrations zone such that the dose is between 0.2 x 10(16) 0.8 alpha-events per milligram (0.15 0.60 displacement atom). transition crystalline aperiodic metamict state occurs over this range. Differential expansion individual layers variations their caused systematic pattern fractures do not...
Research Article| December 01, 2006 Ceramic Waste Forms for Actinides Gregory R. Lumpkin *Australian Nuclear Science and Technology Organisation PMB1, Menai, NSW 2234, Australia E-mail: grl@ansto.gov.au Search other works by this author on: GSW Google Scholar Author Article Information Publisher: Mineralogical Society of America First Online: 09 Mar 2017 Online ISSN: 1811-5217 Print 1811-5209 © the Elements (2006) 2 (6): 365–372. https://doi.org/10.2113/gselements.2.6.365 history Cite View...
Other| August 01, 1995 Geochemical alteration of pyrochlore group minerals: Pyrochlore subgroup Gregory R. Lumpkin; Lumpkin Australian Nuclear Science and Technology Organization, Advanced Materials Program, Menai, NSW, Australia Search for other works by this author on: GSW Google Scholar Rodney C. Ewing University New Mexico, United States American Mineralogist (1995) 80 (7-8): 732–743. https://doi.org/10.2138/am-1995-7-810 Article history first online: 02 Mar 2017 Cite View This Citation...
Up to 0.15 formula unit (f.u.) of U 4+ incorporated in the Zr site zirconolite by firing CaU x (1− ) Ti 2 O 7 compositions argon at 1400°C allows retention 2M polytype. Further substitution for Zr, up 0.4 f.u., produces 4M polytype (containing ∼0.4 f.u. U) plus containing U. The pyrochlore structure 0.6 forms conjunction with contents 0.7 Higher give structure, but solid‐state reactivity even alkoxide‐based preparations becomes increasingly poor > ∼0.7 and hot pressing graphite dies...
Titanium dioxide (TiO2) has often served as a model substrate for experimental sorption studies of environmental contaminants. However, various forms Ti-oxide have been used, and the different properties these materials not thoroughly studied. We investigated uranium on some characterized TiO2 surfaces with particular attention to influence surface area, charge, impurities. The U(VI) differed significantly between samples. Aggressive pretreatment one material remove impurities altered...
Fly ash from a coal-fired power plant was investigated to obtain detailed information on its physical and chemical properties, gain an understanding of potential environmental health impacts associated with disposal in landfills. The studied material produced through combustion Illinois Basin coal trapped within the by electrostatic precipitator. It is finegrained, low-Ca fly containing primarily SiO2, Al2O3, Fe2O3, enriched many toxic elements (e.g., Be, Zn, As, Cd, Tl, Pb, U) factor up 30...
We have studied the long-range average and local structures in Y2Sn2–xZrxO7 (x = 0–2.0) using synchrotron X-ray powder diffraction absorption spectroscopy, respectively, by theoretical methods. While data indicate a clear phase transition from ordered pyrochlore to disordered defect-fluorite at x ∼ 1.0–1.2, near-edge structure (XANES) results Zr L3- Y L2-edges reveal gradual structural evolution across whole compositional range. These findings provide experimental evidence that disorder...
The system Y2Sn2−xZrxO7 (0.0 ≤ x 2.0) undergoes a phase transformation from ordered pyrochlore (Fdm) to defect fluorite (Fmm) actuated by the substitution of Zr for Sn. X-ray diffraction patterns map retention structure up = 1.2. For samples with 1.4–2.0 can be described as in broad terms. Electron are consistent this interpretation; however, they also demonstrate that exhibits strain driven compositional/displacive modulation changes gradually increasing content. Raman spectra gradual anion...
Other| October 01, 1996 Geochemical alteration of pyrochlore group minerals; betafite subgroup Gregory R. Lumpkin; Lumpkin Australian Nuclear Science and Technology Organisation, Materials Division, Menai, N.S.W., Australia Search for other works by this author on: GSW Google Scholar Rodney C. Ewing University New Mexico, United States American Mineralogist (1996) 81 (9-10): 1237–1248. https://doi.org/10.2138/am-1996-9-1022 Article history first online: 02 Mar 2017 Cite View This Citation...
Abstract This review describes nuclear waste forms for high-level (HLW), that is, glasses, ceramics, and glass-ceramics, as well low- intermediate-level (LILW), cement, bitumen, glass, glassy slags, ceramics. Ceramic have the highest chemical durability radiation resistance, are recommended HLW actinide (ACT) immobilization. Most radiation-resistant materials based on phases with a fluorite-related structure (cubic zirconia-based solid solutions, pyrochlore, zirconolite, murataite). Glass is...