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Characterization of Phase and Emulsion Behavior, Surfactant Retention, and Oil Recovery for Novel Alcohol Ethoxycarboxylate Surfactants

Description: This semi-annual technical progress report describes work performed at Clark Atlanta University under DOE Grant No. DE-FG26-97FT97278 during the period October 01, 1997 to April 01, 1998 which covers the first six months of the project. During this reporting period, laboratory space to set up the surfactant characterization measurement system in the Research Science Center was made available. A Ph.D. student in Chemistry was identified and is supported as a Graduate Research Assistant in this project. Her contribution towards this project will form her Ph.D. thesis. The test matrix to perform salinity and temperature scans was established. Supply requests to obtain refined hydrocarbon, surfactant, and crude were processed and supplies obtained. A temperature bath with a control unit to perform temperature scans was obtained on loan from Federal Energy Technology Center, Morgantown, WV. The setting up of the temperature control unit, and associated chiller with water circulation lines is in progress. Tests were conducted on several hybrid surfactants to identify the best surfactants for future experimental work that yield almost equal volumes of top, middle, and bottom phases when mixed with oil and water. The student reviewed the current literature in the subject area, and modeling efforts that were established in previous studies to predict electrical conductivities and inversion phenomena. These activities resulted in one published conference paper, and one student poster paper during this reporting period.
Date: May 1, 1998
Creator: Moeti, Lebone T. & Sampath, Ramanathan
Partner: UNT Libraries Government Documents Department


Description: This semi-annual technical progress report describes work performed at Clark Atlanta University under DOE Grant No. DE-FG26-97FT97278 during the period April 01, 1998 to October 01, 1998 which covers the second six months of the project. Presently work is in progress at the EOR Laboratory, Clark Atlanta University (CAU), to characterize phase and emulsion behavior for a novel, hybrid (ionic/non-ionic), alcohol ethoxycarboxylate surfactant (NEODOX 23-4 from Shell Chemical Company). During this reporting period, salinity scans were completed for 0, 5, 10, 20, 50, 100, 250, 500, 1000, 2000, 3000, 4000, 5000, and 6000 mM salt concentrations at 20, 25, and 30 °C to identify optimal salinity intervals in which all three phases coexist for this surfactant. Temperature scans were also performed at 20 mM salt concentration for various surfactant concentrations ranging from 0 to 60 weight percent at temperatures ranging from 5 to 50 °C to identify optimal surfactant concentration and temperature intervals in which all three phases coexist. This resulted in an "alpha" curve with an interval of temperature in which all three phases coexisted. Presently, temperature scans are being repeated at 100, 250, 500, 1000, and 5000 mM salt concentrations to see whether increase in salt concentration has any effect on the temperature interval. This will provide us better understanding and experimental control of the many variables involved in this research in the future. Following completion of the temperature scans, phase studies will be conducted at CAU, and coreflooding experiments at the facility of our industrial partner, Surtek, Golden, CO.
Date: November 1, 1998
Partner: UNT Libraries Government Documents Department

Relaxation effects in shock-induced transitions in bismuth

Description: The indication given by the baratol experiments is that as the shock in the mixed region progresses and decays, the lead state does not change along a stable Hugoniot but appears to change from a sort of metastable Hugoniot, in accordance with Romain's data, to a stable Hugoniot reminiscent of the earlier results. If this is so, then the Bi I-III transition is exhibiting a relaxation effect similar to that seen in the Sb I-III transition. The transition detected by Romain could then be interpreted as the II-III transition seen in the metastable region. The few experiments outlined here merely hint at an explanation. Additional precision work in the stress range 6-10 GPa, some with thin samples, is needed to resolve this behavior.
Date: January 1, 1981
Creator: Neal, T.R.
Partner: UNT Libraries Government Documents Department

Phase diagrams of the elements

Description: A summary of the pressure-temperature phase diagrams of the elements is presented, with graphs of the experimentally determined solid-solid phase boundaries and melting curves. Comments, including theoretical discussion, are provided for each diagram. The crystal structure of each solid phase is identified and discussed. This work is aimed at encouraging further experimental and theoretical research on phase transitions in the elements. (auth)
Date: September 11, 1975
Creator: Young, D.A.
Partner: UNT Libraries Government Documents Department

Californium oxygen system for 1.50 < O/Cf < 1.72

Description: The californium-oxygen system was studied as a function of temperature, oxygen pressure, and stoichiometry by manometric and x-ray diffraction methods. The results establish rhombohedral Cf$sub 7$O$sub 12$ as the stable compound obtained by heating Cf$sub 2$O$sub 3$ in air. The isobaric oxidation-reduction cycles Cf$sub 2$O$sub 3$ $Yields$ Cf$sub 7$O$sub 12$ $Yields$ Cf$sub 2$O$sub 3$, observed in constant rate of heating (cooling) experiments, occur with large hysteresis. A close parallel to other fluorite related lanthanide and actinide oxide systems is established. (auth)
Date: January 1, 1975
Creator: Turcotte, R. P. & Haire, R. G.
Partner: UNT Libraries Government Documents Department

High temperature vaporization and thermodynamic study of the scandium-- sulfur system

Description: Results of studies on the stoichiometry, structure, vaporization behavior, and thermodynamic properties of the Sc--S system are reported. The thermodynamic results for the stability of ScS(s) are compared with reported results for other transition-metal and rare-earth monosulfides. Various models are discussed in regard to their ability to describe the bonding in these refractory solids. (JRD)
Date: January 1, 1976
Creator: Tuenge, R.T.
Partner: UNT Libraries Government Documents Department

Review of x-ray diffraction studies in uranium alloys

Description: Results of x-ray diffraction experiments investigating equilibrium structures of uranium-base substitutional alloys and routes of transitions between equilibrium structures are critically reviewed. Data on equilibrium alpha, beta, and gamma alloys are presented together with a resume of work on the crystal structures of relevant stable intermetallic compounds. The second part of the review is principally concerned with x-ray diffraction studies of metastable phases: their structure and their mode of formation. Particular attention is given to the sequence of transitional phases found in gamma-quenched and aged uranium alloys, depending on aging time and temperature. The influence of external stresses imposed on the alloys before and during the transitions producing these phases is described in terms of the preferred orientations that may be observed by x-ray diffraction methods. Comparisons are drawn between the general structural behavior of uranium alloys and that of other alloy systems based on metals with allotropies similar to that of uranium. (8 figures, 4 tables, 142 references) (auth)
Date: January 1, 1973
Creator: Yakel, H.L.
Partner: UNT Libraries Government Documents Department

Accurate representations of general textures by a set of weighted grains

Description: The most compact way of describing general texture information is by way of a file of weighted discrete grains. When the textures are strong, this results in a great saving of necessary parameters. The most efficient way is a random file from which grains with low weights get discarded. This method is routine and independent of any preknowledge of the texture or even the symmetries. Typically, the order of 100 grains are sufficient for strong textures or fiber textures. Furthermore, these grains files are directly in the kind of format that is useful for computer simulation of current anisotropic properties or future texture development. For textures that are not very sharp, but nevertheless are not properly represented as random (which would imply isotropic properties), one may also use weighted-grains files, but here the number of grains needed may be large for an accurate representation. We have found that on the order of 1000 weighted grains are sufficient for most cases. When the symmetries are known, grains that are regularly (rather than randomly) arranged in orientation space are useful -- again better when they are weighted.
Date: January 1, 1990
Creator: Kocks, U.F. (Los Alamos National Lab., NM (USA)); Kallend, J.S. & Biondo, A.C. (Illinois Inst. of Tech., Chicago, IL (USA). Dept. of Metallurgy and Materials Engineering)
Partner: UNT Libraries Government Documents Department

Advances in characterization of materials: alloys and ceramics

Description: The advantages of high resolution electron diffraction and imaging have been revealed in a wide variety of metallic systems, providing insight into the mechanisms of such phase transformations as ordering, spinodal decomposition, grain boundary precipitation, and the martensitic reaction. Structural discontinuities in interphase interfaces (atomic plane ledges) and grain boundaries (plane matching defects) have been identified with high precision, and compositional variations on an atomic scale have been detected, including solute segregation within approximately 10 A of a grain boundary. In the study of ceramics, primary effort has been directed toward the detection of thin intergranular films with notable success. Atomic dimension microledges have also been revealed in crystallization interfaces, polytype boundaries and transformation fronts, and compositional variations near grain boundaries have recently been recorded in lattice images of a Magnesium Sialon. It therefore appears that the technique holds equal promise for analysis of the fundamental mechanisms of crystallization, phase transformation, diffusion and solute segregation in ceramics as well as metallic alloy systems. The work presented here represents some of the potential of high resolution methods and is an initial step towards complete atomic characterization of materials. The most desirable progression of such research should lead to the attainment of structural images similar to those that are currently being used to explore the atomic arrangements in mineralogical specimens. This requires only a slight improvement in the contrast transfer characteristics of present day electron optics.
Date: May 1, 1978
Creator: Thomas, G.
Partner: UNT Libraries Government Documents Department

A novel phase transition in alloys

Description: The intermediate-phase of the intermetallic alloy CsPb is shown to be a plastic crystal characterized by jump reorientations of Cs{sub 4}Pb{sub 4} structural units. The wave vector variation of elastic and quasielastic intensities is well reproduced by a simple model if independent structural units jumping between the four orientations observed in the crystal at room temperature. This represents the first observation of a plastic crystal phase in a metal alloy. 17 refs., 6 figs.
Date: September 1, 1991
Creator: Saboungi, M.L. & Price, D.L.
Partner: UNT Libraries Government Documents Department