P
P. G. Allen
Researcher at Lawrence Berkeley National Laboratory
Publications - 13
Citations - 1191
P. G. Allen is an academic researcher from Lawrence Berkeley National Laboratory. The author has contributed to research in topics: X-ray absorption fine structure & Uranyl. The author has an hindex of 11, co-authored 13 publications receiving 1136 citations. Previous affiliations of P. G. Allen include Lawrence Livermore National Laboratory.
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Journal ArticleDOI
Investigation of Aquo and Chloro Complexes of UO22+, NpO2+, Np4+, and Pu3+ by X-ray Absorption Fine Structure Spectroscopy
TL;DR: The ability to use XAFS speciation results to calculate equilibrium constants and the relationship of these results to previous studies are discussed.
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Coordination chemistry of trivalent lanthanide and actinide ions in dilute and concentrated chloride solutions.
TL;DR: Results suggest that the extent of chloride complexation is increasing across the An3+ series, i.e., Cl- ion replacement of the H2O at high chloride thermodynamic activities.
Journal ArticleDOI
Structural features of iron phosphate glasses
Gaya Kanishka Marasinghe,Mevlüt Karabulut,Chandra S. Ray,Delbert E. Day,Mark G. Shumsky,William B. Yelon,Corwin H. Booth,P. G. Allen,David K. Shuh +8 more
TL;DR: In this paper, the structures and valence states of iron ions in several iron phosphate glasses with batch compositions similar to 40Fe2O3-60P2O5 (mol%) have been investigated using Mossbauer spectroscopy, X-ray absorption fine-structure spectrographs (XAFS), XPS, differential thermal (DTA), differential thermal and thermo-gravimetric (TGA) analysis and x-ray and neutron diffraction.
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An EXAFS study of uranium(VI) sorption onto silica gel and ferrihydrite
Tobias Reich,Henry Moll,Thuro Arnold,Melissa A. Denecke,Christoph Hennig,Gerhard Geipel,Gert Bernhard,H. Nitsche,P. G. Allen,Jerome J. Bucher,Norman M. Edelstein,David K. Shuh +11 more
TL;DR: In this paper, the structural parameters of the nearneighbor surrounding of uranium(VI) sorbed onto silica gel and ferrihydrite surfaces have been determined by U LIII-edge extended X-ray absorption fine structure (EXAFS) analysis.
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Characterization of Hydrous Uranyl Silicate by EXAFS
Tobias Reich,Henry Moll,Melissa A. Denecke,Gerhard Geipel,Gert Bernhard,H. Nitsche,P. G. Allen,Jerome J. Bucher,N. Kaltsoyannis,Norman M. Edelstein,David K. Shuh +10 more
TL;DR: Extended X-ray absorption fine structure (EXAFS) analysis was performed on uranyl orthosilicate, (U02)2Si04 · 2H20, and uranium(VI) sorbed onto silicic acid and silica gel as discussed by the authors.