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Novel Regenerated Solvent Extraction Processes for the Recovery of Carboxylic Acids or Ammonia from Aqueous Solutions Part II. Recovery of Ammonia from Sour Waters

Description: Two novel regenerated solvent extraction processes are examined. The first process has the potential to reduce the energy costs inherent in the recovery of low-volatility carboxylic acids from dilute aqueous solutions. The second process has the potential for reducing the energy costs required for separate recovery of ammonia and acid gases (e.g. CO{sub 2} and H{sub 2}S) from industrial sour waters. The recovery of carboxylic acids from dilute aqueous solution can be achieved by extraction with… more
Date: March 1, 1990
Creator: Poole, L. J. & King, C. J.
Partner: UNT Libraries Government Documents Department
open access

Novel Regenerated Solvent Extraction Processes for the Recovery of Carboxylic Acids or Ammonia from Aqueous Solutions Part I. Regeneration of Amine-Carboxylic Acid Extracts

Description: Two novel regenerated solvent extraction processes are examined. The first process has the potential to reduce the energy costs inherent in the recovery of low-volatility carboxylic acids from dilute aqueous solutions. The second process has the potential for reducing the energy costs required for separate recovery of ammonia and acid gases (e.g. CO{sub 2} and H{sub 2}S) from industrial sour waters. The recovery of carboxylic acids from dilute aqueous solution can be achieved by extraction with… more
Date: March 1, 1990
Creator: Poole, L. J. & King, C. J.
Partner: UNT Libraries Government Documents Department
open access

Diffusion of trichloroethylene through the threaded joints of PVC (polyvinylchloride) pipe

Description: The data engineers and scientists use to determine if the groundwater supply is contaminated are derived from analysis of samples taken largely from monitoring wells. For these data to be reliable several factors must be considered. One factor is the integrity of the monitoring well. In this project, emphasis has been placed on the potential impact on water quality caused by diffusion across the threaded joints of PVC pipe. In this study, the diffusion of trichloroethylene across several common… more
Date: December 1, 1990
Creator: Jerome, Karen M.
Partner: UNT Libraries Government Documents Department
open access

Effects of egg incubation condition on the post-hatching growth and performance of the snapping turtle, Chelydra serpentina

Description: The effect of incubation temperature on the post-hatching growth and performance capacities of the common snapping turtle, Chelydra serpentina was investigated in the laboratory. Turtle eggs were collected from four sites in New York State and randomly assigned to four incubation temperature treatments to produce males (constant 26{degree}C and downshifted 30-26-30{degree}C) and females (constant 30{degree}C and upshifted 26-30-26{degree}C) under constant and altered temperature regimes. The in… more
Date: December 1, 1990
Creator: Ryan, K. M.
Partner: UNT Libraries Government Documents Department
open access

Theoretical studies of non-Newtonian and Newtonian fluid flow through porous media

Description: A comprehensive theoretical study has been carried out on the flow behavior of both single and multiple phase non-Newtonian fluids in porous media. This work is divided into three parts: development of numerical and analytical solutions; theoretical studies of transient flow of non-Newtonian fluids in porous media; and applications of well test analysis and displacement efficiency evaluation to field problems. A fully implicit, integral finite difference model has been developed for simulation … more
Date: February 1, 1990
Creator: Wu, Yu-Shu.
Partner: UNT Libraries Government Documents Department
open access

Theoretical Studies of Non-Newtonian and Newtonian Fluid Flowthrough Porous Media

Description: A comprehensive theoretical study has been carried out on the flow behavior of both single and multiple phase non-Newtonian fluids in porous media. This work is divided into three parts: (1) development of numerical and analytical solutions; (2) theoretical studies of transient flow of non-Newtonian fluids in porous media; and (3) applications of well test analysis and displacement efficiency evaluation to field problems. A fully implicit, integral finite difference model has been developed for… more
Date: February 1, 1990
Creator: Wu, Y.S.
Partner: UNT Libraries Government Documents Department
open access

A three-dimensional transient neutronics routine for the TRAC-PF1 reactor thermal hydraulic computer code

Description: No present light water reactor accident analysis code employs both high state of the art neutronics and thermal-hydraulics computational algorithms. Adding a modern three-dimensional neutron kinetics model to the present TRAC-PFI/MOD2 code would create a fully up to date pressurized water reactor accident evaluation code. After reviewing several options, it was decided that the Nodal Expansion Method would best provide the basis for this multidimensional transient neutronic analysis capability.… more
Date: May 1, 1990
Creator: Bandini, B.R.
Partner: UNT Libraries Government Documents Department
open access

Studies of DNA supercoiling in vivo and in vitro

Description: This thesis describes a number of diverse experiments whose common theme is to elaborate some aspect of DNA supercoiling. The torsion elastic constant of DNA is measure as a function of superhelix density using the technique of picosecond Time Resolved Fluorescence Polarization Anisotropy (FPA) of intercalated ethidium bromide. The results agree with theories which predict that the anisotropy decay should vary with the square root of the relative viscosity. This experiment furthermore demonstra… more
Date: October 1, 1990
Creator: Cook, D. N.
Partner: UNT Libraries Government Documents Department
open access

Quantum Monte Carlo methods and lithium cluster properties

Description: Properties of small lithium clusters with sizes ranging from n = 1 to 5 atoms were investigated using quantum Monte Carlo (QMC) methods. Cluster geometries were found from complete active space self consistent field (CASSCF) calculations. A detailed development of the QMC method leading to the variational QMC (V-QMC) and diffusion QMC (D-QMC) methods is shown. The many-body aspect of electron correlation is introduced into the QMC importance sampling electron-electron correlation functions by u… more
Date: December 1, 1990
Creator: Owen, R. K.
Partner: UNT Libraries Government Documents Department
open access

Characterization of leaky faults

Description: Leaky faults provide a flow path for fluids to move underground. It is very important to characterize such faults in various engineering projects. The purpose of this work is to develop mathematical solutions for this characterization. The flow of water in an aquifer system and the flow of air in the unsaturated fault-rock system were studied. If the leaky fault cuts through two aquifers, characterization of the fault can be achieved by pumping water from one of the aquifers, which are assumed … more
Date: May 1, 1990
Creator: Shan, Chao
Partner: UNT Libraries Government Documents Department
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