Publications

1992
S. B. Graves, Ringuest, J. L., and Bard, J. F., Recent Developments in Screening Methods for Nondominated Solutions in Multiobjective Optimization. Computers & Operations Research 19(7), 1992, pp. 683–694.
R. B. Machemehl and Ward, W. V., “Regional Arterial (Super Street) Concepts,” Transportation Research Record, 1992.Abstract
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P. D. Condo and Johnston, K. P., “RETROGRADE VITRIFICATION OF POLYMERS WITH COMPRESSED FLUID DILUENTS - EXPERIMENTAL CONFIRMATION,” Macromolecules, vol. 25, pp. 6730-6732, 1992. Publisher's VersionAbstract
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G. E. Speitel Jr and Leonard, J. M., “A Sequencing Biofilm Reactor for the Treatment of Chlorinated Solvents Using Methanotrophs,” Water Environment Research, vol. 64, no. 5, pp. 712-719, 1992.
Y. P. Sun, Fox, M. A., and Johnston, K. P., “SPECTROSCOPIC STUDIES OF PARA-(N,N-DIMETHYLAMINO)BENZONITRILE AND ETHYL PARA-(N,N-DIMETHYLAMINO)BENZOATE IN SUPERCRITICAL TRIFLUOROMETHANE, CARBON-DIOXIDE, AND ETHANE,” Journal of the American Chemical Society, vol. 114, pp. 1187-1194, 1992. Publisher's VersionAbstract
Absorption and emission spectral maxima, bandwidths, and fractional contribution of twisted intramolecular charge transfer states to the observed emission of p-(NN-dimethylamino)benzonitrile (DMABN) and ethyl p-(NN-dimethylamino)benzoate (DMAEB) in supercritical CHF3, CO2, and C2H6 are presented. By examining a wide range of reduced densities from 0.05 to 2.2, we have discovered a characteristic density dependence in the spectral shifts in all three fluids. A model for these spectral effects is proposed, differentiating intermolecular interactions in three distinct regions: gas-phase solute-solvent clustering, clustering in the near-critical region, and ’’liquidlike’’ solvation. Even below a reduced density of 0.5, clustering of solvent about solute is already prevalent.
Y. P. Sun, Bennett, G., Johnston, K. P., and Fox, M. A., “STUDIES OF SOLUTE SOLVENT INTERACTIONS IN MIXTURES OF SUPERCRITICAL FLUIDS USING FLUORESCENCE SPECTROSCOPY,” Journal of Physical Chemistry, vol. 96, pp. 10001-10007, 1992. Publisher's VersionAbstract
Solute-solvent interactions of (dimethylamino)benzonitrile and ethyl (dimethylamino)benzoate in mixtures of supercritical trifluoromethane and carbon dioxide are studied using fluorescence spectroscopy. The density dependence of solvation in the mixtures is similar to that in the pure supercritical fluids. The polar component CHF3 in the mixtures clusters preferentially about a solute molecule. This clustering is also density dependent. Bulk and local (microscopic) solvent effects in the in different density regions are rationalized based on the Onsager reaction field model and on the concepts of local density and composition.
E. M. Taleff, Ruano, O. A., Wolfenstine, J., and Sherby, O. D., “Superplastic Behavior of a Fine-Grained Mg-9Li Material at Low Homologous Temperature,” Journal of Materials Research, vol. 7, pp. 2131–2135, 1992. LinkAbstract
No abstract available. Only available as a scanned document.
R. B. Gupta, Panayiotou, C. G., Sanchez, I. C., and Johnston, K. P., “THEORY OF HYDROGEN-BONDING IN SUPERCRITICAL FLUIDS,” Aiche Journal, vol. 38, pp. 1243-1253, 1992. Publisher's VersionAbstract
The degree of hydrogen bonding and macroscopic thermodynamic properties for pure and mixed fluids are predicted with the hydrogen bonding lattice fluid (LFHB) equation of state over a wide range in density encompassing the gas, liquid and supercritical states. The model is successful for molecules forming complex self-associated networks, in this case pure methanol, ethanol, and water, and the mixture 1-hexanol-SF6. In supercritical water, significant hydrogen bonding is still present despite all the thermal energy and is highly pressure- and temperature-dependent. A fundamental description of pressure and temperature effects on hydrogen bonding is presented for a well-defined case, the formation of a complex between a donor and acceptor in an inert solvent, where no self-association is present. The partial molar enthalpy and volume change on complexation both become pronounced near the critical point, where the density is highly variable with temperature and pressure.
1991
J. F. Bard and Feo, T. A., An Algorithm for the Manufacturing Equipment Selection Problem. IIE Transactions 23(1), 1991, pp. 83–92.
T. A. Edmunds and Bard, J. F., “Algorithms for Nonlinear Mathematical Bilevel Programs,” IEEE Trans. Systems, Man, and Cybernetics, vol. 21, pp. 83–89, 1991.
J. F. Bard and Bennett, J. E., Arc Reduction and Path Preference in Stochastic Acyclic Networks. Management Science 37(2), 1991, pp. 198–215.
T. J. Kruger, Machemehl, R. B., and Ward, W. V., “ARTERIAL STREETS,” 1991.Abstract
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R. B. Machemehl, Automotive Diagnostic Technology. Center for Transportation Research, Bureau of Engineering Research, the University of Texas at Austin, 1991.Abstract
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G. E. Speitel Jr and Alley Jr, E. R., “Bioremediation of Unsaturated Soils Contaminated with Chlorinated Solvents,” Journal of Hazardous Materials, vol. 28, pp. 81–90, 1991.
R. M. Lemert and Johnston, K. P., “CHEMICAL COMPLEXING AGENTS FOR ENHANCED SOLUBILITIES IN SUPERCRITICAL FLUID CARBON-DIOXIDE,” Industrial & Engineering Chemistry Research, vol. 30, pp. 1222-1231, 1991. Publisher's VersionAbstract
The effect of the strong Lewis base tri-n-butyl phosphate (TBP) on the solubility of benzoic acid and hydroquinone (HQ) in supercritical fluid carbon dioxide is reported. TBP is shown to be a much stronger cosolvent for these solutes than methanol. For example, 2% TBP increases hydroquinone’s solubility by a factor of 250. The principles of chemical reaction equilibria are combined with the Peng-Robinson equation of state in order to model these results. The behavior of the hydroquinone-carbon dioxide-TBP system is shown to be attributable to the formation of an HQ-TBP2 complex having an enthalpy of formation of -18.9 kcal/mol. The performance of this chemical model is compared to that of a recently developed density-dependent local composition (DDLC) model.
G. E. Speitel Jr and Closmann, F. B., “Chlorinated Solvent Biodegradation by Methanotrophs in Unsaturated Soils,” Journal of Environmental Engineering, American Society of Civil Engineers, vol. 117, no. 5, pp. 541-558, 1991.
T. J. Kruger, Lee, C. E., Machemehl, R. B., and Ward, W. V., “Design guidelines and other considerations for strategic arterial streets,” 1991.Abstract
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T. J. Kruger, Lee, C. E., Machemehl, R. B., and Ward, W. V., “DESIGN GUIDELINES AND OTHER CONSIDERATIONS FOR STRATEGIC ARTERIAL STREETS. INTERIM REPORT”. 1991.Abstract
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J. F. Bard and Bejjani, W. A., Designing Telecommunications Networks for the Reseller Market. Management Science 37(9), 1991, pp. 1125–1146.
S. D. Wert, Bard, J. F., and H., A., “deSilva and T,” A. Feo (1991). A Simulation Analysis of Semi-Automated Mail Processing Facilities. Journal of the Operational Research Society, vol. 42, pp. 1071–1086, 1991.

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