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Looking Backward, Looking Forward: MLA Members Speak
- April Alliston, Elizabeth Ammons, Jean Arnold, Nina Baym, Sandra L. Beckett, Peter G. Beidler, Roger A. Berger, Sandra Bermann, J.J. Wilson, Troy Boone, Alison Booth, Wayne C. Booth, James Phelan, Marie Borroff, Ihab Hassan, Ulrich Weisstein, Zack Bowen, Jill Campbell, Dan Campion, Jay Caplan, Maurice Charney, Beverly Lyon Clark, Robert A. Colby, Thomas C. Coleman III, Nicole Cooley, Richard Dellamora, Morris Dickstein, Terrell Dixon, Emory Elliott, Caryl Emerson, Ann W. Engar, Lars Engle, Kai Hammermeister, N. N. Feltes, Mary Anne Ferguson, Annie Finch, Shelley Fisher Fishkin, Jerry Aline Flieger, Norman Friedman, Rosemarie Garland-Thomson, Sandra M. Gilbert, Laurie Grobman, George Guida, Liselotte Gumpel, R. K. Gupta, Florence Howe, Cathy L. Jrade, Richard A. Kaye, Calhoun Winton, Murray Krieger, Robert Langbaum, Richard A. Lanham, Marilee Lindemann, Paul Michael Lützeler, Thomas J. Lynn, Juliet Flower MacCannell, Michelle A. Massé, Irving Massey, Georges May, Christian W. Hallstein, Gita May, Lucy McDiarmid, Ellen Messer-Davidow, Koritha Mitchell, Robin Smiles, Kenyatta Albeny, George Monteiro, Joel Myerson, Alan Nadel, Ashton Nichols, Jeffrey Nishimura, Neal Oxenhandler, David Palumbo-Liu, Vincent P. Pecora, David Porter, Nancy Potter, Ronald C. Rosbottom, Elias L. Rivers, Gerhard F. Strasser, J. L. Styan, Marianna De Marco Torgovnick, Gary Totten, David van Leer, Asha Varadharajan, Orrin N. C. Wang, Sharon Willis, Louise E. Wright, Donald A. Yates, Takayuki Yokota-Murakami, Richard E. Zeikowitz, Angelika Bammer, Dale Bauer, Karl Beckson, Betsy A. Bowen, Stacey Donohue, Sheila Emerson, Gwendolyn Audrey Foster, Jay L. Halio, Karl Kroeber, Terence Hawkes, William B. Hunter, Mary Jambus, Willard F. King, Nancy K. Miller, Jody Norton, Ann Pellegrini, S. P. Rosenbaum, Lorie Roth, Robert Scholes, Joanne Shattock, Rosemary T. VanArsdel, Alfred Bendixen, Alarma Kathleen Brown, Michael J. Kiskis, Debra A. Castillo, Rey Chow, John F. Crossen, Robert F. Fleissner, Regenia Gagnier, Nicholas Howe, M. Thomas Inge, Frank Mehring, Hyungji Park, Jahan Ramazani, Kenneth M. Roemer, Deborah D. Rogers, A. LaVonne Brown Ruoff, Regina M. Schwartz, John T. Shawcross, Brenda R. Silver, Andrew von Hendy, Virginia Wright Wexman, Britta Zangen, A. Owen Aldridge, Paula R. Backscheider, Roland Bartel, E. M. Forster, Milton Birnbaum, Jonathan Bishop, Crystal Downing, Frank H. Ellis, Roberto Forns-Broggi, James R. Giles, Mary E. Giles, Susan Blair Green, Madelyn Gutwirth, Constance B. Hieatt, Titi Adepitan, Edgar C. Knowlton, Jr., Emanuel Mussman, Sally Todd Nelson, Robert O. Preyer, David Diego Rodriguez, Guy Stern, James Thorpe, Robert J. Wilson, Rebecca S. Beal, Joyce Simutis, Betsy Bowden, Sara Cooper, Wheeler Winston Dixon, Tarek el Ariss, Richard Jewell, John W. Kronik, Wendy Martin, Stuart Y. McDougal, Hugo Méndez-Ramírez, Ivy Schweitzer, Armand E. Singer, G. Thomas Tanselle, Tom Bishop, Mary Ann Caws, Marcel Gutwirth, Christophe Ippolito, Lawrence D. Kritzman, James Longenbach, Tim McCracken, Wolfe S. Molitor, Diane Quantic, Gregory Rabassa, Ellen M. Tsagaris, Anthony C. Yu, Betty Jean Craige, Wendell V. Harris, J. Hillis Miller, Jesse G. Swan, Helene Zimmer-Loew, Peter Berek, James Chandler, Hanna K. Charney, Philip Cohen, Judith Fetterley, Herbert Lindenberger, Julia Reinhard Lupton, Maximillian E. Novak, Richard Ohmann, Marjorie Perloff, Mark Reynolds, James Sledd, Harriet Turner, Marie Umeh, Flavia Aloya, Regina Barreca, Konrad Bieber, Ellis Hanson, William J. Hyde, Holly A. Laird, David Leverenz, Allen Michie, J. Wesley Miller, Marvin Rosenberg, Daniel R. Schwarz, Elizabeth Welt Trahan, Jean Fagan Yellin
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- Journal:
- PMLA / Publications of the Modern Language Association of America / Volume 115 / Issue 7 / December 2000
- Published online by Cambridge University Press:
- 23 October 2020, pp. 1986-2078
- Print publication:
- December 2000
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Thermodynamic Modeling of Neptunium(V) Solubility in Concentrated Na-CO3-HCO3-Cl-ClO4-H-OH-H2O Systems
- Craig F. Novak, Kevin E. Roberts
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- Journal:
- MRS Online Proceedings Library Archive / Volume 353 / 1994
- Published online by Cambridge University Press:
- 15 February 2011, 1119
- Print publication:
- 1994
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Safety assessments of nuclear waste repositories often require estimation of actinide solubilities as they vary with groundwater composition. Although a considerable amount of research has been done on the solubility and speciation of actinides,1,2 relatively little has been done to unify these data into a model applicable to concentrated brines. Numerous authors report data on the aqueous chemical properties of Np(V) in NaClO4, Na2CO3, and NaCl media, but a consistent thermodynamic model for predicting these properties is not available. To meet this need, a model was developed to describe the solubility of Np(V) in Na-Cl-ClO4-CO3 aqueous systems, based on the Pitzer activity coefficient formalism for concentrated electrolytes. Hydrolysis and/or carbonate complexation are the dominant aqueous reactions with the neptunyl ion in these systems. Literature data for neptunyl ion extraction and solubility are used to parameterize an integrated model for Np(V) solubility in the Np(V)-Na-CO3-HCO3-Cl-ClO4-H-OH-H2O system. The resulting model is tested against additional solubility and extraction data, and compared with Np(V) solubility experiments in complex synthetic brines.
Transport Modeling in a Finite Fractured Rock Domain*
- Craig F. Novak
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- Journal:
- MRS Online Proceedings Library Archive / Volume 294 / 1992
- Published online by Cambridge University Press:
- 01 January 1992, 831
- Print publication:
- 1992
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The Waste Isolation Pilot Plant (WIPP) is a U.S. Department of Energy facility intended to demonstrate the safe disposal of transuranic nuclear waste. The WIPP is located in the thick halite beds of the Salado Formation in the Delaware Basin of southeastern New Mexico. Overlying the repository is the Culebra Dolomite Member of the Rustler Formation, a dolomitic unit containing accessory minerals such as calcite, gypsum, and clays. The Culebra is the predominant continuous water-bearing unit in the area. Part of the scientific demonstration of the safety of WIPP involves understanding and estimating what might happen should the WIPP inadvertently be intruded by exploration boreholes long after the WIPP has been decommissioned. Should such a breach occur, it is possible that dissolved transuranic waste could be transported up a borehole and into the Culebra, through which it could eventually reach the accessible environment. The rates and mechanisms for actinide transport in Culebra Dolomite are being investigated as a component of repository performance assessment.
The two primary mechanisms for delaying solute release from a double porosity system are called physical and chemical retardation, both of which retard solute migration relative to bulk water flow. Physical retardation occurs when solutes diffuse out of the advective transport regions (fractures) and into diffusive transport regions (matrix). Results of hydrologic field tests suggest that the Culebra behaves as a double porosity medium. Chemical retardation occurs when chemical interactions between dissolved species and mineral surfaces remove solutes from the aqueous phase. Some fracture surfaces in the Culebra are clay-lined, and, because clays can have a large potential for chemical interactions with solutes (e.g., ion exchange or adsorption), it is possible that fracture linings alone may cause significant retardation of any actinides that could reach the Culebra. This report examines these two features in Culebra transport: delimiting the parameter space where a fully two-dimensional model is needed, and examining the importance of clay linings during transport.
Numerical simulations with the FMT (Fracture Matrix Transport) finite difference model in a finite, idealized double porosity system were performed to: 1) delineate parameter values for which a set of two coupled one-dimensional equations is insufficient to describe behavior and a fully two-dimensional representation is needed, 2) compare chemical retardation by ion exchange for fractures with and without a clay lining, and 3) compare physical and chemical retardation by ion exchange as a function of fracture velocity. The simulations differ from others in that the matrix is finite, and thus can become saturated with tracers introduced into the domain. The modeling suggests that the chemical retardation caused by clay linings may not be important in a double porosity system. Over a wide range, a single parameter group essentially determines the complexity of the model.