DOCSLIB.ORG

Proquest Dissertations

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Proquest Dissertations INFORMATION TO USERS This manuscript has been reproduced from the microfilm master UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bieedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to t)e removed, a note will indicate the deletion. Oversize materials (e.g.. maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6” x 9” black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. Bell & Howell Information and Learning 300 North Zeeb Road. Ann Arbor. Ml 48106-1346 USA UIVQ800-521-0600 Spin-Orbit Configuration Interaction Calculations of Actinide and Lanthanide Systems DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Scott Raymond BrozeU, M. S. ***** The Ohio State University 1999 Dissertation Committee: Approved by Professor Russell M. Pitzer, Adviser Professor Eric Herbst Adviser Professor Emeritus Isaiah Shavitt Graduate Program in Chemical Physics UMI Number: 9951<^6 UMI MScroform 9951636 Copyright 2000 by Bell & Howell Wbrmadon and Learning Company. Ail rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. Bell & Howell Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, MI 48106-1346 ABSTRACT Spectroscopic properties of actinide and lanthanide systems were calculated via spin-orbit multireference configuration interaction (SOMRCI) methods using rela- tivistic efiective potentials (REPs) and correlation consistent (cc) basis sets. A program for generating electron configuration lists was written in C + + using the standard template library. Based on an earlier program, this rewrite has no restrictions on the number of basis functions or the number of electrons and has an improved user interface. Uranium REP core sizes were studied. A 78-electron core size, valence space of 6s~6p^5f^6d^7s^, leads to energy levels in mediocre agreement with experiment and to uranyl ion (UO 2 bond lengths that are a few picometers too short. Including the electrons in the valence space corrects these problems. Including, in addition, the electrons in the valence space yields worse results because relativistic effects are large for this subshell. cc-pVDZ and cc-pVTZ basis sets for actinides and lanthanides have been de­ veloped. In a study on trends in correlation and SO energies are similar to those found in Dunning’s original work on the correlation energy in the oxygen atom. Exponents of Gaussian functions optimized for both correlation and SO energy are u nearly identical to those optimized for correlation energy only. Contraction coeffi­ cients for Gaussian basis sets for use with REPs are best determined from atomic natural orbitals, as indicated by a study on the oxygen atom. The ground and excited states of AmOg AmOg and CmOg ^‘'"were calculated. The ground state of the americyl cation is ‘^^ 3 / 2 u- The first ligand to metal charge transfer (LMCT) state is The ground and first LMCT states of the isoelectronic dioxoamericum(V) and curyl cations are and ^Ilo+g. Agreement with experimental excitation energies is good. Other electronic / <— / transitions have been tentatively assigned. Electronic spectra of various cations of uranium, plutonium, americium, curium, praseodymium, and europium, were calculated. For and Pr^^, the agreement is within 20% of experiment for SOMRCI singles and doubles (SOh'IRCISD) using 78 electron core REPs for U and a 46 electron core REP for Pr and cc-pVDZ basis sets. For U, either using a cc-pVTZ basis set or using a 68 electron core REP improves the energy levels to within 10%. All of these cations have been more extensively studied experimentally as dopants in solid crystalline materials. A model of crystalline calcium fluoride was developed and electronic spectra of these cations as dopants in CaFg were calculated. Generally, the agreement is within 25% of experiment. However, the ground state crystal field splittings of the p ions Am^"^, Cm^"^, and Eu^'*' are about a factor of 20 smaller than the corresponding experimental values, which are less than 50 cm~^. ui DEDICATION Shall I compare thee to a summer’s day? Thou art more lovely and more temperate. Rough winds do shake the darling buds of May, And su m m er’s lease hath all too short a date. Sometime too hot the eye of heaven shines, And often is his gold complexion dimm’d; And every fair from fair sometime declines. By chance or nature’s changing course untrinun’d; But thy eternal summer shall not fade Nor lose possession of that fair thou ow’st: Nor shall Death brag thou wander’st in his shade. When in eternal lines to time thou grow’st: So long as men can breathe or eyes can see. So long lives this, and this gives life to thee. William Shakespeare IV ACKNOWLEDGMENTS I thank Dr. Russell M. Pitzer for his thoughtful guidance, boundless patience, and professional deportment. He is an exemplary scientist, a comprehensive scholar, and a quintessential advisor. I thank many colleagues for their Mendship and assistance, especially Lars Ojamae, Wolfgang Kiichle, Jo Ann Balozy, Phillip Christiansen, Clinton Nash, Michael Seth, Bert de Jong, Steve Parker, Gary Kedziora, and former and current Pitzer group students: Ke Zhao, Zhiyong Zhang, Jean-Phillipe Blaudeau, and Spiridoula Matsika. VITA 1989 ........................................................................B .S . — Case Western Reserve Univer­ sity, Cleveland, U.S.A. 1993 ........................................................................M. S. — John Carroll University, Cleveland, U.S.A. 1993-1999 .............................................................Graduate School Fellowship, Teach­ ing Associate and Research Associate, Ohio State University PUBLICATIONS “Atomic Orbital Basis Sets for Use with Efiective Core Potentials,” J.-P. Blaudeau, S. R. Brozell, S. Matsika, Z. Zhang, and R. M. Pitzer, Int. J. Quantum Chem. Submitted. FIELDS OF STUDY Major Field: Chemical Physics Studies in Theoretical Chemistry: Professor Russell M. Pitzer VI TABLE OF CONTENTS Page Abstract............................................................................................................................. ii Dedication......................................................................................................................... iv Acknowledgments ............................................................................................................ v V i t a ................................................................................................................................... vi List of Tables................................................................................................................... x List of Figures ................................................................................................................ xiv Chapters: 1. Introduction ............................................................................................................ 1 2. Configuration Generation Softw are .................................................................. 9 2.1 Introduction ................................................................................................ 9 2.2 Multireference Configuration E xp losion ............................................... 10 2.3 The Original CGDBG Program ............................................................ 15 2.4 Design of the New CGDBG Program ................................................... 19 2.4.1 First Implementation................................................................... 19 2.4.2 Final Implementation ................................................................ 21 2.4.3 User In terface................................................................................ 24 2.4.4 Program Notes ............................................................................. 24 2.5 Profiles of CGDBG Programs ................................................................ 25 2.6 Conclusions ................................................................................................ 27 vu 3. Relativistic Effective Potential Development.................................................. 28 3.1 Introduction ............................................................................................... 28 3.2 B ackground................................................................................................ 29 3.2.1 Relativistic Quantum Physics ................................................. 29 3.2.1-1 Special Relativity ............................................................ 30 3.2.1.2 The Klein-Gordon Equation ......................................
Load more

Recommended publications
  • Free and Open Source Software for Computational Chemistry Education
    Free and Open Source Software for Computational Chemistry Education Susi Lehtola∗,y and Antti J. Karttunenz yMolecular Sciences Software Institute, Blacksburg, Virginia 24061, United States zDepartment of Chemistry and Materials Science, Aalto University, Espoo, Finland E-mail: [email protected].fi Abstract Long in the making, computational chemistry for the masses [J. Chem. Educ. 1996, 73, 104] is finally here. We point out the existence of a variety of free and open source software (FOSS) packages for computational chemistry that offer a wide range of functionality all the way from approximate semiempirical calculations with tight- binding density functional theory to sophisticated ab initio wave function methods such as coupled-cluster theory, both for molecular and for solid-state systems. By their very definition, FOSS packages allow usage for whatever purpose by anyone, meaning they can also be used in industrial applications without limitation. Also, FOSS software has no limitations to redistribution in source or binary form, allowing their easy distribution and installation by third parties. Many FOSS scientific software packages are available as part of popular Linux distributions, and other package managers such as pip and conda. Combined with the remarkable increase in the power of personal devices—which rival that of the fastest supercomputers in the world of the 1990s—a decentralized model for teaching computational chemistry is now possible, enabling students to perform reasonable modeling on their own computing devices, in the bring your own device 1 (BYOD) scheme. In addition to the programs’ use for various applications, open access to the programs’ source code also enables comprehensive teaching strategies, as actual algorithms’ implementations can be used in teaching.
    [Show full text]
  • A Protein Engineered to Bind Uranyl Selectively and with Femtomolar Affinity
    ARTICLES PUBLISHED ONLINE: 26 JANUARY 2014 | DOI: 10.1038/NCHEM.1856 A protein engineered to bind uranyl selectively and with femtomolar affinity Lu Zhou1†, Mike Bosscher1†, Changsheng Zhang2,3†,SalihO¨ zc¸ubukc¸u1, Liang Zhang1, Wen Zhang1, Charles J. Li1, Jianzhao Liu1, Mark P. Jensen4, Luhua Lai2,3* and Chuan He1* 21 ∼ Uranyl (UO2 ), the predominant aerobic form of uranium, is present in the ocean at a concentration of 3.2 parts per 109 (13.7 nM); however, the successful enrichment of uranyl from this vast resource has been limited by the high concentrations of metal ions of similar size and charge, which makes it difficult to design a binding motif that is selective for uranyl. Here we report the design and rational development of a uranyl-binding protein using a computational screening process in the initial search for potential uranyl-binding sites. The engineered protein is thermally stable and offers very high affinity and selectivity for uranyl with a Kd of 7.4 femtomolar (fM) and >10,000-fold selectivity over other metal ions. We also demonstrated that the uranyl-binding protein can repeatedly sequester 30–60% of the uranyl in synthetic sea water. The chemical strategy employed here may be applied to engineer other selective metal-binding proteins for biotechnology and remediation applications. ranium is the key element for nuclear-energy production and Through billions of years of evolution nature has produced is important in many other applications. The most stable and strategies to recognize beneficial or toxic metal ions with high Urelevant uranium ion in aerobic environments is the uranyl sensitivity and selectivity.
    [Show full text]
  • Hierarchically-Structured Metalloprotein Composite
    ARTICLE There are amendments to this paper https://doi.org/10.1038/s41467-020-14709-y OPEN Hierarchically-structured metalloprotein composite coatings biofabricated from co-existing condensed liquid phases ✉ Franziska Jehle 1, Elena Macías-Sánchez1, Sanja Sviben1, Peter Fratzl1, Luca Bertinetti 1 & ✉ Matthew J. Harrington 1,2 1234567890():,; Complex hierarchical structure governs emergent properties in biopolymeric materials; yet, the material processing involved remains poorly understood. Here, we investigated the multi- scale structure and composition of the mussel byssus cuticle before, during and after for- mation to gain insight into the processing of this hard, yet extensible metal cross-linked protein composite. Our findings reveal that the granular substructure crucial to the cuticle’s function as a wear-resistant coating of an extensible polymer fiber is pre-organized in con- densed liquid phase secretory vesicles. These are phase-separated into DOPA-rich proto- granules enveloped in a sulfur-rich proto-matrix which fuses during secretion, forming the sub-structure of the cuticle. Metal ions are added subsequently in a site-specific way, with iron contained in the sulfur-rich matrix and vanadium coordinated by DOPA-catechol in the granule. We posit that this hierarchical structure self-organizes via phase separation of specific amphiphilic proteins within secretory vesicles, resulting in a meso-scale structuring that governs cuticle function. 1 Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam,
    [Show full text]
  • Depleted Uranium Technical Brief
    Disclaimer - For assistance accessing this document or additional information,please contact [email protected]. Depleted Uranium Technical Brief United States Office of Air and Radiation EPA-402-R-06-011 Environmental Protection Agency Washington, DC 20460 December 2006 Depleted Uranium Technical Brief EPA 402-R-06-011 December 2006 Project Officer Brian Littleton U.S. Environmental Protection Agency Office of Radiation and Indoor Air Radiation Protection Division ii iii FOREWARD The Depleted Uranium Technical Brief is designed to convey available information and knowledge about depleted uranium to EPA Remedial Project Managers, On-Scene Coordinators, contractors, and other Agency managers involved with the remediation of sites contaminated with this material. It addresses relative questions regarding the chemical and radiological health concerns involved with depleted uranium in the environment. This technical brief was developed to address the common misconception that depleted uranium represents only a radiological health hazard. It provides accepted data and references to additional sources for both the radiological and chemical characteristics, health risk as well as references for both the monitoring and measurement and applicable treatment techniques for depleted uranium. Please Note: This document has been changed from the original publication dated December 2006. This version corrects references in Appendix 1 that improperly identified the content of Appendix 3 and Appendix 4. The document also clarifies the content of Appendix 4. iv Acknowledgments This technical bulletin is based, in part, on an engineering bulletin that was prepared by the U.S. Environmental Protection Agency, Office of Radiation and Indoor Air (ORIA), with the assistance of Trinity Engineering Associates, Inc.
    [Show full text]
  • A Structural and Spectroscopic Study of the First Uranyl Selenocyanate, [Et4n]3[UO2(Ncse)5]
    inorganics Article A Structural and Spectroscopic Study of the First Uranyl Selenocyanate, [Et4N]3[UO2(NCSe)5] Stefano Nuzzo, Michelle P. Browne, Brendan Twamley, Michael E. G. Lyons and Robert J. Baker * School of Chemistry, Trinity College, University of Dublin, 2 Dublin, Ireland; [email protected] (S.N.); [email protected] (M.P.B.); [email protected] (B.T.); [email protected] (M.E.G.L.) * Correspondence: [email protected]; Tel.: +353-1-896-3501; Fax: +353-1-671-2826 Academic Editors: Stephen Mansell and Steve Liddle Received: 30 October 2015; Accepted: 4 February 2016; Published: 16 February 2016 Abstract: The first example of a uranyl selenocyanate compound is reported. The compound [Et4N]3[UO2(NCSe)5] has been synthesized and fully characterized by vibrational and multinuclear (1H, 13C{1H} and 77Se{1H}) NMR spectroscopy. The photophysical properties have also been recorded and trends in a series of uranyl pseudohalides discussed. Spectroscopic evidence shows that the U–NCSe bonding is principally ionic. An electrochemical study revealed that the reduced uranyl(V) species is unstable to disproportionation and a ligand based oxidation is also observed. The structure of [Et4N]4[UO2(NCSe)5][NCSe] is also presented and Se¨ ¨ ¨ H–C hydrogen bonding and Se¨ ¨ ¨ Se chalcogen–chalcogen interactions are seen. Keywords: uranyl; structural determination; photophysics 1. Introduction The chemistry of uranium in its highest oxidation state has held scientists fascination for a long 2+ period of time. The uranyl moiety, [UO2] , is well studied in aqueous phases due, in part, to relevance in the nuclear waste treatment. Moreover, the photophysical properties of uranyl were first used in ancient roman times in colored glass [1], whilst comprehensive understanding of the bonding, and therefore photophysical properties, has come from both experiment and theory.
    [Show full text]
  • Computational Chemistry
    G UEST E DITORS’ I NTRODUCTION COMPUTATIONAL CHEMISTRY omputational chemistry has come of chemical, physical, and biological phenomena. age. With significant strides in com- The Nobel Prize award to John Pople and Wal- puter hardware and software over ter Kohn in 1998 highlighted the importance of the last few decades, computational these advances in computational chemistry. Cchemistry has achieved full partnership with the- With massively parallel computers capable of ory and experiment as a tool for understanding peak performance of several teraflops already on and predicting the behavior of a broad range of the scene and with the development of parallel software for efficient exploitation of these high- end computers, we can anticipate that computa- tional chemistry will continue to change the scientific landscape throughout the coming cen- tury. The impact of these advances will be broad and encompassing, because chemistry is so cen- tral to the myriad of advances we anticipate in areas such as materials design, biological sci- ences, and chemical manufacturing. Application areas Materials design is very broad in scope. It ad- dresses a diverse range of compositions of matter that can better serve structural and functional needs in all walks of life. Catalytic design is one such example that clearly illustrates the promise and challenges of computational chemistry. Al- most all chemical reactions of industrial or bio- chemical significance are catalytic. Yet, catalysis is still more of an art (at best) or an empirical fact than a design science. But this is sure to change. A recent American Chemical Society Sympo- sium volume on transition state modeling in catalysis illustrates its progress.1 This sympo- sium highlighted a significant development in the level of modeling that researchers are em- 1521-9615/00/$10.00 © 2000 IEEE ploying as they focus more and more on the DONALD G.
    [Show full text]
  • Procedure for Determining Uranium, Plutonium and Americium by Extraction-Chromatographic Procedures
    Procedure for determining uranium, plutonium and americium by extraction-chromatographic procedures H-U/Pu/Am-AWASS-01 Authors: M. Beyermann D. Obrikat Federal coordinating office for drinking water, groundwater, wastewater, sludge, waste and wastewater of nuclear power plants (Leitstelle für die Überwachung der Radioaktivität in Trinkwasser, Grundwasser, Abwasser, Klärschlamm, Reststoffen und Abfällen) ISSN 1865-8725 Version October 2000 Procedures manual for monitoring of radioactive substances in the environment and of external radiation (Messanleitungen für die „Überwachung radioaktiver Stoffe in der Umwelt und externer Strahlung“) H-U/Pu/Am-AWASS-01-01 Procedure for determining uranium, plutonium and americium by means of extraction- chromatographic procedures 1 Scope This procedure serves to simultaneously determine the uranium isotopes U-234, U-235 and U-238, the plutonium isotopes Pu-238, Pu-239 and Pu-240, as well as the americium isotope Am-241 in samples of wastewater from nuclear facilities. It furthermore offers an option of determining the curium isotopes Cm-242 and Cm-244 without further effort. For determining Pu-241, reference is made to pro- cedure H-Pu-241-AWASS-01 of these measuring instructions. 2 Sampling As far as sampling is concerned, reference is made to procedure H-SPEKT- AWASS-01 of these measuring instructions. The sample of the wastewater to be analysed is acidified with ca. 10 ml of concentrated nitric acid (14 mol·l-1) per litre to a pH of about 1. The stability of the acidic reaction needs to be monitored, in particular if the sample is stored for an extended period of time. This procedure ensures that a detection limit of 0,05 Bq·l-1 for alpha-emitters is reached in a sample volume of 0,1 litres to 0,25 litres and thus complies with the nuclear safety standard 1504 of the Nuclear Safety Standards Commission (1).
    [Show full text]
  • Anion Photoelectron Spectroscopic and Relativistic Coupled-Cluster Studies of − Uranyl Dichloride Anion, Uo2cl2 Mary Marshall, Zhaoguo Zhu, Junzi Liu, Kit H
    Journal of Molecular Spectroscopy 379 (2021) 111496 Contents lists available at ScienceDirect Journal of Molecular Spectroscopy journal homepage: www.elsevier.com/locate/yjmsp Article Anion photoelectron spectroscopic and relativistic coupled-cluster studies of * uranyl dichloride anion, UO2Cl2 Mary Marshall, Zhaoguo Zhu, Junzi Liu, Kit H. Bowen, Lan Cheng < Department of Chemistry, The Johns Hopkins University, Baltimore, MD 21218, USA ARTICLEINFO ABSTRACT Keywords: A joint relativistic coupled-cluster and experimental photoelectron (PE) spectroscopic study of the uranyl Coupled-cluster * dichloride anion, UO2Cl2 , is reported. Sophisticated electronic-structure calculations predict the photodetach- Anion photoelectron * ment of UO2Cl to involve a U 5f electron and to be followed by significant geometry relaxation. Therefore, the Uranyl 2 adiabatic electron affinity (EAa) of the uranyl dichloride neutral molecule, UO2Cl2, and the vertical detachment * energy (VDE) of its anion, UO2Cl2 , provide valuable information about its uranium 5f orbital energies. The EAa value was computed to be 3.15 eV. The VDE value was calculated to be 3.55 eV by augmenting the computed EAa with a shift derived from a Franck–Condon simulation using coupled-cluster potential energy surfaces. The VDE, which corresponds to the highest intensity peak in the PE spectrum, was measured to be 3.69 , 0.20 eV, in good agreement with the computed value. The origin transition in the PE spectrum, whose electron binding energy corresponds to the EAa, was assigned to the feature at 3.2 , 0.20 eV, consistent with the computed EAa. 1. Introduction at 20323 cm*1 with nearly harmonic vibrational progressions at a frequency of 840 cm*1 [15].
    [Show full text]
  • Novel Heterometallic Uranyl-Transition Metal Materials: Structure, Topology, and Solid State Photoluminescence Properties † ‡ ‡ § Germań E
    Article Cite This: Inorg. Chem. 2019, 58, 7243−7254 pubs.acs.org/IC Novel Heterometallic Uranyl-Transition Metal Materials: Structure, Topology, and Solid State Photoluminescence Properties † ‡ ‡ § Germań E. Gomez, J. August Ridenour, Nicole M. Byrne, Alexander P. Shevchenko, ‡ and Christopher L. Cahill*, † Instituto de Investigaciones en Tecnología Química (INTEQUI), Area de Química General e Inorganicá “Dr. G. F. Puelles,” Facultad de Química, Bioquímica y Farmacia, Chacabuco y Pedernera, Universidad Nacional de San Luis, Almirante Brown, 1455, 5700 San Luis, Argentina ‡ Department of Chemistry, The George Washington University, Science and Engineering Hall, 800 22nd Street, NW, Washington, DC 20052, United States § Samara Center for Theoretical Materials Science, Samara University, 34, Moskovskoye shosse, Samara, 443086, Russia *S Supporting Information ABSTRACT: Six new uranyl hybrid materials have been synthesized solvothermally ′ ′ ′ ′ ′′ utilizing the ligands 2,2 -bipyridine-3,3 -dicarboxylic acid (H2L) and 2,2 :6 ,2 -terpyridine (TPY). The six compounds are classified as either molecular complexes (I0O0 connectivity), · · [(UO2)(L)(TPY)] H2O(1), [Ni(TPY)2][(UO2)(L)2] 3H2O(2), and [Cu(TPY)2]- · − 0 3 [(UO2)(L)2] 3H2O(3), or 3D metal organic frameworks (MOFs, I O connectivity), · [Cu2(UO2)2(OH)(C2H3O2)(L)3(TPY)2] 6H2O(4), [Zn2(UO2)2(OH)(NO3)(C2H3O2)- · · (L)3(TPY)2] 4H2O(5), and Na[Ni(UO2)3(OH)(O)(L)3] 9H2O(6). A discussion of the influence of transition metal incorporation, chelating effects of the ligand, and synthesis conditions on the formation of uranyl materials is presented. The structure of compound 6 is of particular note due to large channel-like voids with a diameter of approximately 19.6 Å.
    [Show full text]
  • Actinide Separation Inspired by Self-Assembled Metal-Polyphenolic Nanocages
    Page 1 of 9 1 2 3 4 5 6 7 Actinide separation inspired by self-assembled metal-polyphenolic 8 9 nanocages 10 †, §, †, ‡, § † # † † ⊥ 11 Lei Mei, * Peng Ren, Qun-yan Wu, Yu-bin Ke, Jun-shan Geng, Kang Liu, Xue-qing Xing, 12 Zhi-wei Huang, † Kong-qiu Hu, † Ya-lan Liu, † Li-yong Yuan, † Guang Mo, ⊥ Zhong-hua Wu, ⊥ John K 13 Gibson, ＆ Zhi-fang Chai, †, ¶ Wei-qun Shi †, * 14 15 † Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China 16 ‡ State key Laboratory of Nuclear Resources and Environment, School of Chemistry, School of Nuclear Science and Engineering, 17 East China University of Technology, Nanchang 330013, China. 18 ⊥Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China 19 # Spallation Neutron Source Science Center, Dongguan 523803, China 20 ¶ Engineering Laboratory of Advanced Energy Materials, Ningbo Institute of Industrial Technology, Chinese Academy of Sciences, 21 Ningbo 315201, China 22 ＆ Chemical Sciences Division, Lawrence Berkeley National Laboratory (LBNL), Berkeley, California 94720, USA 23 KEYWORDS: actinides; nano-extraction; uranyl-organic nanocage; self-assembly; pyrogallol[4]arene 24 25 26 ABSTRACT: The separation of actinides has a vital place in nuclear fuel reprocessing, recovery of radionuclides and 27 remediation of environmental contamination. Here we propose a new paradigm of nanocluster-based actinide separation, 28 namely nano-extraction, that can achieve efficient sequestration of uranium in an unprecedented form of giant coordination 29 nanocages using a cone-shaped macrocyclic pyrogallol[4]arene as the extractant. The U24-based hexameric 30 pyrogallol[4]arene nanocages with distinctive [U2PG2] binuclear units (PG = pyrogallol), that rapidly assembled in situ in 31 monophasic solvent, were identified by single-crystal XRD, MALDI-TOF-MS, NMR, and SAXS/SANS.
    [Show full text]
  • Icp-Oes and Xas Investigation of the Phytoextraction of Lanthanides and Actinides from Aqueous Environmental Solutions 1J.G
    ICP-OES AND XAS INVESTIGATION OF THE PHYTOEXTRACTION OF LANTHANIDES AND ACTINIDES FROM AQUEOUS ENVIRONMENTAL SOLUTIONS 1J.G. Parsons, 2J.L. Gardea-Torresdey, 1K.J. Tiemann, 1J.R. Peratta-Videa, 1E. Gomez, and 1J.H. Gonzalez 1Department of Environmental Science and Engineering, 500 W. University Ave., University of Texas at El Paso, El Paso TX. 79968; Phone: (915)747-5359; Fax: (915)747- 5748. 2Department of Chemistry, 500 W. University Ave, University of Texas at El Paso, El Paso, TX 79968; Phone: (915)747-5359; Fax: (915)747-5748. Abstract Use of nuclear power raises questions about nuclear waste, especially how it can be minimized and stored safely. One alternative is extraction and reprocessing of the uranium from the spent fuel. But the reprocessing of spent fuel is very expensive and requires use of ion exchange resins that cannot be reused. Some biomaterials have been studied for their ability to extract lanthanides and actinides, such as uranyl cation from solution. In this study, the extraction of uranyl nitrate, uranyl acetate, and europium nitrate from aqueous solution using an alfalfa biomaterial was investigated. Major factors affecting the sorption of cations from solution are pH, time, and interfering cations. Studies were performed to investigate each of the above parameters. In addition, capacity studies were performed for comparison purposes with common methods to extract these cations from solutions. To investigate the chemical environment where uranyl and europium cations were bound to the alfalfa biomass, X-ray absorption spectroscopy studies were performed. The X-Ray absorption near-edge structure showed that europium(III) and uranyl cations remained in the same oxidation state when bound to the biomass, with characteristic LIII-edge energies for uranyl and europium(III) of 17.172 keV and 6.981 keV, respectively.
    [Show full text]
  • Separation of Radioactive Elements from Rare Earth Element-Bearing Minerals
    metals Review Separation of Radioactive Elements from Rare Earth Element-Bearing Minerals Adrián Carrillo García 1, Mohammad Latifi 1,2, Ahmadreza Amini 1 and Jamal Chaouki 1,* 1 Process Development Advanced Research Lab (PEARL), Chemical Engineering Department, Ecole Polytechnique de Montreal, C.P. 6079, Succ. Centre-ville, Montreal, QC H3C 3A7, Canada; [email protected] (A.C.G.); mohammad.latifi@polymtl.ca (M.L.); [email protected] (A.A.) 2 NeoCtech Corp., Montreal, QC H3G 2N7, Canada * Correspondence: [email protected] Received: 8 October 2020; Accepted: 13 November 2020; Published: 17 November 2020 Abstract: Rare earth elements (REE), originally found in various low-grade deposits in the form of different minerals, are associated with gangues that have similar physicochemical properties. However, the production of REE is attractive due to their numerous applications in advanced materials and new technologies. The presence of the radioactive elements, thorium and uranium, in the REE deposits, is a production challenge. Their separation is crucial to gaining a product with minimum radioactivity in the downstream processes, and to mitigate the environmental and safety issues. In the present study, different techniques for separation of the radioactive elements from REE are reviewed, including leaching, precipitation, solvent extraction, and ion chromatography. In addition, the waste management of the separated radioactive elements is discussed with a particular conclusion that such a waste stream can be
    [Show full text]