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The Utilization of the Microflora Indigenous to and Present in Oil-Bearing Formations to Selectively Plug the More Porous Zones Thereby Increasing Oil Recovery During Waterflooding, Class 1 (open access)

The Utilization of the Microflora Indigenous to and Present in Oil-Bearing Formations to Selectively Plug the More Porous Zones Thereby Increasing Oil Recovery During Waterflooding, Class 1

The objectives of this project were (1) to demonstrate the in situ microbial population in a fluvial dominated deltaic reservoir could be induced to proliferate to such an extent that they will selectively restrict flow in the more porous zones in the reservoir thereby forcing injection water to flow through previously unswept areas thus improving the sweep efficiency of the waterflood and (2) to obtain scientific validation that microorganisms are indeed responsible for the increased oil recovery. One expected outcome of this new technology was the prolongation of economical life of the reservoir, i.e. economical oil recovery should continue for much longer periods in areas of the reservoir subjected to the MPPM technology than it would if it followed its historic trend.
Date: February 2, 2000
Creator: Stephens, James O.; Brown, Lewis R. & Vadie, Alex A.
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 100, No. 272, Ed. 1 Wednesday, February 2, 2000 (open access)

Altus Times (Altus, Okla.), Vol. 100, No. 272, Ed. 1 Wednesday, February 2, 2000

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: February 2, 2000
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Advertiser (Alvin, Tex.), Ed. 1 Wednesday, February 2, 2000 (open access)

The Alvin Advertiser (Alvin, Tex.), Ed. 1 Wednesday, February 2, 2000

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: February 2, 2000
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Optimist (Abilene, Tex.), Vol. 88, No. 34, Ed. 1, Wednesday, February 2, 2000 (open access)

The Optimist (Abilene, Tex.), Vol. 88, No. 34, Ed. 1, Wednesday, February 2, 2000

Tri-weekly student newspaper from Abilene Christian University in Abilene, Texas that includes local, state and campus news along with advertising.
Date: February 2, 2000
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
McMurry War Whoop (Abilene, Tex.), Vol. 76, No. 8, Ed. 1, Wednesday, February 2, 2000 (open access)

McMurry War Whoop (Abilene, Tex.), Vol. 76, No. 8, Ed. 1, Wednesday, February 2, 2000

Weekly student newspaper from McMurry University in Abilene, Texas that includes local, state and campus news along with advertising.
Date: February 2, 2000
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, February 2, 2000 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, February 2, 2000

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: February 2, 2000
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Rattler (San Antonio, Tex.), Vol. 86, No. 5, Ed. 1 Wednesday, February 2, 2000 (open access)

The Rattler (San Antonio, Tex.), Vol. 86, No. 5, Ed. 1 Wednesday, February 2, 2000

Biweekly student newspaper from St. Mary's University in San Antonio, Texas that includes campus news along with advertising.
Date: February 2, 2000
Creator: St. Mary's University (San Antonio, Tex.)
Object Type: Newspaper
System: The Portal to Texas History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 84, No. 121, Ed. 1 Wednesday, February 2, 2000 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 84, No. 121, Ed. 1 Wednesday, February 2, 2000

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: February 2, 2000
Creator: unknown
Object Type: Newspaper
System: The Gateway to Oklahoma History
The impact of process parameters on gold elimination from soldered connector assemblies (open access)

The impact of process parameters on gold elimination from soldered connector assemblies

Minimizing the likelihood of solder joint embrittlement in connectors is realized by reducing or eliminating retained Au plating and/or Au-Sn intermetallic compound formation from the assemblies. Gold removal is performed most effectively by using a double wicking process. When only a single wicking procedure can be used, a higher soldering temperature improves the process of Au removal from the connector surfaces and to a nominal extent, removal of Au-contaminated solder from the joint. A longer soldering time did not appear to offer any appreciable improvement toward removing the Au-contaminated solder from the joint. Because the wicking procedure was a manual process, it was operator dependent.
Date: February 2, 2000
Creator: VIANCO,PAUL T. & KILGO,ALICE C.
Object Type: Article
System: The UNT Digital Library
Using Java to visualize and manipulate large arrays of neutron scattering data (open access)

Using Java to visualize and manipulate large arrays of neutron scattering data

The Intense Pulsed Neutron Source at Argonne National Laboratory is a world class pulsed neutron source with thirteen instruments designed to characterize materials using time-of-flight neutron scattering techniques. For each instrument, a collimated pulse of neutrons is directed to a material sample. The neutrons are scattered by the sample and detected by arrays of detectors. The type, number and arrangement of detectors vary widely from instrument to instrument, depending on which properties of materials are being studied. In all cases, the faster, higher energy neutrons reach the detectors sooner than the lower energy neutrons. This produces a time-of-flight spectrum at each detector element. The time-of-flight spectrum produced by each detector element records the scattering intensity at hundreds to thousands of discrete time intervals. Since there are typically between two hundred and ten thousand distinct detector elements, a single set of raw data can include millions of points. Often many such datasets are collected for a single sample to determine the effect of different conditions on the microscopic structure and dynamics of the sample. In this project, Java was used to construct a portable highly interactive system for viewing and operating on large collections of time-of-flight spectra. Java performed surprisingly well …
Date: February 2, 2000
Creator: Mikkelson, D.; Worlton, T.; Chatterjee, A.; Hammonds, J. & Chen, D.
Object Type: Article
System: The UNT Digital Library
Novel CO{sub 2}-thickeners for improved mobility control (open access)

Novel CO{sub 2}-thickeners for improved mobility control

The objective of this study was to design, synthesize, and characterize thickening agents for dense carbon dioxide and to evaluate their solubility and viscosity-enhancing potential in CO{sub 2}. Previously, fluoroacrylate homopolymers and fluorinated telechelic ionomers were shown to increase the viscosity of carbon dioxide by a factor of 3--4 at concentrations of 2--3 at concentrations of 4--5 wt%. This report details the findings for several new types of carbon dioxide thickening candidates. Hydrocarbon-fluorocarbon random copolymers, sulfonated hydrocarbon-fluorocarbon random copolymers, semifluorinated trialkyltin fluorides and small hydrogen-bounding compounds were evaluated.
Date: February 2, 2000
Creator: Enick, Dr. Robert M.; Beckman, Dr. Eric J. & Hamilton, Dr. Andrew
Object Type: Report
System: The UNT Digital Library
Computed Tomography (CT) Standards (open access)

Computed Tomography (CT) Standards

There is currently no standardized method to check the measurement capabilities of computed tomography (CT) systems within industry. The current method to determine the functionality of CT systems is by use of a test phantom to represent the actual part to be tested. A standard method to check the software algorithms when measuring such parameters as density of a material and the size of an object is not readily available. Many different materials are evaluated by CT systems. A set of standards necessitates the inclusion of materials that cover the gambit of materials encountered. The Federal Manufacturing and Technologies (FM and T) CT standards are designed to accommodate a variety of materials and several different sizes. This provides a method to check the CT system for size measurement capabilities and material density measurement as well as aid in optimizing the geometric parameters of the machine configuration.
Date: February 2, 2000
Creator: Hubert, R. R. & Beach, J. M.
Object Type: Report
System: The UNT Digital Library
Ferroelectric and piezoelectric properties of MOCVD Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}PbTiO{sub 3} epitaxial thin films (open access)

Ferroelectric and piezoelectric properties of MOCVD Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}PbTiO{sub 3} epitaxial thin films

The authors have grown epitaxial Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3} (PMN) and (1-x)(Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3})-x(PBTiO{sub 3})(PMN-PT)thin films by metalorganic chemical vapor deposition at 700 -- 780 C on (100) SrTiO{sub 3} and SrRuO{sub 3}/SrTiO{sub 3} substrates. The zero-bias permittivity and loss measured at room temperature and 10 kHz for 220 nm thick pure PMN films were 900 and 1.5%, respectively. For PMN-PT films the small-signal permittivity ranged from 1000 to 1500 depending on deposition conditions and Ti content; correspondingly low values for the zero-bias dielectric loss between 1 and 5% were determined for all specimens. For PMN-PT with x of approximately 0.30--0.35, polarization hysteresis with P{sub r}{approximately}18{mu}C/cm{sup 2} was obtained. Initial piezoresponse data are discussed.
Date: February 2, 2000
Creator: Baumann, P. K.; Bai, G. R.; Streiffer, S. K.; Ghosh, K.; Auciello, O.; Stemmer, S. et al.
Object Type: Article
System: The UNT Digital Library
Practical superconductor development for electrical power applications: Quarterly report for the period ending December 31, 1999 (open access)

Practical superconductor development for electrical power applications: Quarterly report for the period ending December 31, 1999

This is a multiyear experimental research program focused on improving relevant material properties of high-T{sub c} superconductors (HTSS) and on development of fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of the Argonne (ANL) program. Recent results on substrate deposition for coated conductors, vortex studies, development of hardened Ag-alloy sheaths for powder-in-tube conductors, and sol-gel processing of NdBa{sub 2}Cu{sub 3}O{sub x} (Nd-123) are presented.
Date: February 2, 2000
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Phase transitions in insertion electrodes for lithium batteries (open access)

Phase transitions in insertion electrodes for lithium batteries

Phase transitions that occur during lithium insertion into layered and framework structures are discussed in the context of their application as positive and negative electrodes in lithium-ion batteries. The discussion is focused on the two-dimensional structures of graphite, LiNi{sub 1{minus}x}M{sub x}O{sub 2} (M = Co, Ti and Mg), and Li{sub 1.2}V{sub 3}O{sub 8}; examples of framework structures with a three-dimensional interstitial space for Li{sup +}-ion transport include the spinel oxides and intermetallic compounds with zinc-blende-type structures. The phase transitions are discussed in terms of their tolerance to lithium insertion and extraction and to the chemical stability of the electrodes in the cell environment.
Date: February 2, 2000
Creator: Thackeray, M. M.
Object Type: Article
System: The UNT Digital Library
Certification of solar products - The Florida experience (open access)

Certification of solar products - The Florida experience

Florida legislation enacted in 1976 directed the Florida Solar Energy Center (FSEC) to develop standards for solar energy systems manufactured or sold in the state, establish criteria for testing the performance of solar energy systems, and provide a means to display compliance with approved performance tests for these systems. This mandate has been effectively implemented for both solar domestic water heating and solar pool heating systems. With growing interest and markets for photovoltaic systems, plans are presently being developed to expand the scope of the mandate to include photovoltaic technology. This paper discusses four complementary facets of a photovoltaic (PV) system certification program. They include PV module performance characterization and rating; PV system design review and approval; examination and authorization of photovoltaic system installers; and inspection and acceptance testing of PV system installation. The suggested photovoltaic system process builds on lessons learned from over 20 years of testing, certifying and labeling of solar thermal collectors, and the certification of solar thermal systems.
Date: February 2, 2000
Creator: POST,HAROLD N.; ROLAND,JAMES D.; VENTRE,GERARD G. & HUGGINS,JAMES C.
Object Type: Article
System: The UNT Digital Library
Novel CO{sub 2}-thickeners for improved mobility control (open access)

Novel CO{sub 2}-thickeners for improved mobility control

The objective of this study was to incorporate carbon dioxide-philic functionalities into the structure of a telechelic ionomers in an attempt to design a carbon dioxide-thickener. Alkyl analogs of these end-functionalized polymers have been successfully employed in dilute concentration to increase the viscosity of organic liquids or to induce gelation. The ionic end-groups associated in solution, establishing a viscosity enhancing macromolecular structure. More dramatic viscosity changes have been attained at very dilute concentrations with low MW associating compounds than with ultra-high MW polymers. The apparent molecular weight of the associative network greatly exceeds the MW of the covalently-bounded polymer in solution, yet the relatively low molecular weight of the compound favors its solubilization.
Date: February 2, 2000
Creator: Enick, Dr. Robert M.; Beckman, Dr. Eric J. & Hamilton, Dr. Andrew
Object Type: Report
System: The UNT Digital Library
Novel CO{sub 2}-thickeners for improved mobility control (open access)

Novel CO{sub 2}-thickeners for improved mobility control

The objective of this study was to design, synthesize, and characterize thickening agents for dense carbon dioxide and to evaluate their solubility and viscosity-enhancing potential in CO{sub 2}. Previously, hydrocarbon-fluorocarbon random copolymers, sulfated hydrocarbon-fluorocarbon random copolymers, semifluorinated trialkyltin fluorides and small hydrogen-bonding compounds were evaluated. Random copolymers of styrene and heptadecafluorodecyl acrylate yielded substantial increases in viscosity. The amount of styrene varied between 22--40 mole% in the copolymer. Falling cylinder viscometry results indicated that the 29% styrene--71% fluoroacrylate copolymer induced (at 295K and 34.5 Mpa) increases of 10, 60 and 250 at copolymer concentrations of 1, 3 and 5wt%, respectively.
Date: February 2, 2000
Creator: Enick, Dr. Robert M.; Beckman, Dr. Eric J. & Hamilton, Dr. Andrew
Object Type: Report
System: The UNT Digital Library
Precision Cleaning Titanium Components (open access)

Precision Cleaning Titanium Components

Clean bond surfaces are critical to the operation of diffusion bonded titanium engine components. These components can be contaminated with machining coolant, shop dirt, and fingerprints during normal processing and handling. These contaminants must be removed to achieve acceptable bond quality. As environmental concerns become more important in manufacturing, elimination of the use of hazardous materials is desired. For this reason, another process (not using nitric-hydrofluoric acid solution) to clean titanium parts before bonding was sought. Initial cleaning trials were conducted at Honeywell to screen potential cleaning techniques and chemistries. During the initial cleaning process screening phase, Pratt and Whitney provided Honeywell with machined 3 inch x 3 inch x 1 inch titanium test blocks. These test blocks were machined with a water-based machining coolant and exposed to a normal shop environment and handling. (Honeywell sectioned one of these blocks into smaller samples to be used for additional cleanliness verification analyses.) The sample test blocks were ultrasonically cleaned in alkaline solutions and AUGER analysis was used by Honeywell FM and T to validate their cleanliness. This information enabled selection of final cleaning techniques and solutions to be used for the bonding trials. To validate Honeywell's AUGER data and to verify …
Date: February 2, 2000
Creator: Hand, T.E. & Bohnert, G.W.
Object Type: Report
System: The UNT Digital Library
A comparison of spin observable predictions for RHIC (open access)

A comparison of spin observable predictions for RHIC

There have been many versions of spin-dependent parton distributions in the literature. Although most agree with present data within uncertainties, they are based upon different physical assumptions. Some physical models are discussed and the corresponding predictions for double spin asymmetries are shown. A summary of the most feasible measurements in the appropriate kinematic regions at RHIC, which should yield the most useful information about the polarized gluon distribution, is given.
Date: February 2, 2000
Creator: Ramsey, G. P.
Object Type: Article
System: The UNT Digital Library
Spall formation in solution mined storage caverns based on a creep and fracture analysis (open access)

Spall formation in solution mined storage caverns based on a creep and fracture analysis

Because of limited direct observation, understanding of the interior conditions of the massive storage caverns constructed in Gulf Coast salt domes is realizable only through predictions of salt response. Determination of the potential for formation of salt spans, leading to eventual salt falls, is based on salt creep and fracture using the Multimechanism-Deformation Coupled Fracture (MCDF) model. This is a continuum model for creep, coupled to continuum damage evolution. The model has been successfully tested against underground results of damage around several test rooms at the Waste Isolation Pilot Plant (WIPP). Model simulations, here, evaluate observations made in the Strategic Petroleum Reserve (SPR) storage caverns, namely, the accumulation of material on cavern floors and evidence of salt falls. A simulation of a smooth cavern wall indicates damage is maximum at the surface but diminishes monotonically into the salt, which suggests the source of salt accumulation is surface sluffing. If a protuberance occurs on the wall, fracture damage can form beneath the protuberance, which will eventually cause fracture, and lead to a salt fall.
Date: February 2, 2000
Creator: MUNSON,DARRELL E.
Object Type: Article
System: The UNT Digital Library
Ray-tracing studies for a whole-viewing-angle retroreflector (open access)

Ray-tracing studies for a whole-viewing-angle retroreflector

The APS Survey and Alignment team uses LEICA laser trackers for the majority of their alignment tasks. These instruments utilize several different retroreflectors for tracking the path of the laser interferometer. Currently in use are open-air corner cubes with an acceptance angle of {+-}20{degree}, corner cube prisms with an acceptance angle of {+-}50{degree}, and a Cat's eye with an acceptance angle of {+-}60{degree}. Best measurement results can be achieved by using an open-air corner cube that eliminates the need for the laser beam to travel through a different medium before it returns to the instrument detector. However, the trade off is a small acceptance angle. In order to overcome the limitations of the small acceptance angles, Takatsuji et al. has proposed the creation of a full-viewing-angle retroreflector. Based on the notion that the radius R{sub 1} of a common Cat's eye is proportional to R{sub 2}, one can write: R{sub 1} = (n {minus} 1)R{sub 2}. In the case that n, the refractive index of glass, equals 2, the radii R{sub 1} and R{sub 2} are identical, and one can create a solid sphere Cat's eye. This design has the advantages that no adhesives are used to bond the two …
Date: February 2, 2000
Creator: Yang, B. & Friedsam, H.
Object Type: Article
System: The UNT Digital Library
Technical investigation of a pyrophoric event involving corrosion products from HEU ZPPR fuel plates (open access)

Technical investigation of a pyrophoric event involving corrosion products from HEU ZPPR fuel plates

A pyrophoric event recently occurred which involved corrosion products collected from highly-enriched uranium (HEU) fuel plates used in the Zero Power Physics Reactor (ZPPR). This paper summarizes the event and its background, and presents the results of an investigation into its source and mechanism. The investigation focused on characterization of corrosion product samples similar to those involved in the event using thermo-gravimetric analysis (TGA). Burning curve TGA tests were performed to measure the ignition temperature and hydride fractions of corrosion products in several different conditions to assess the effects of passivation treatment and long-term storage on chemical reactivity. The hydride fraction and ignition temperature of the corrosion products were found to be strongly dependent on the corrosion extent of the source metal. The results indicate that the energy source for the event was a considerable quantity of uranium hydride present in the corrosion products, but the specific ignition mechanism could not be identified.
Date: February 2, 2000
Creator: Totemeier, T. C.
Object Type: Article
System: The UNT Digital Library
The Autocatalytic Behavior of Trimethylindium During Thermal Decomposition (open access)

The Autocatalytic Behavior of Trimethylindium During Thermal Decomposition

Pyrolysis of trimethylindium (TMIn) in a hot-wall flow-tube reactor has been investigated at temperatures between 573 and 723 K using a modulated molecular-beam mass-sampling technique and detailed numerical modeling. The TMIn was exposed to various mixtures of carrier gases: He, H{sub 2}, D{sub 2}, and C{sub 2}H{sub 4}, in an effort to elucidate the behavior exhibited by this compound in different chemical environments. The decomposition of TMIn is a heterogeneous, autocatalytic process with an induction period that is carrier-gas dependent and lasts on the order of minutes. After activation of the tube wall, the thermolysis exhibits a steady-state behavior that is surface mediated. This result is contrary to prior literature reports, which state that decomposition occurs in the gas phase via successive loss of the CH{sub 3} ligands. This finding also suggests that the bond dissociation energy for the (CH{sub 3}){sub 2}In-CH{sub 3} bond derived from flow-tube investigations is erroneous and should be reevaluated.
Date: February 2, 2000
Creator: McDaniel, Anthony H. & Allendorf, M. D.
Object Type: Report
System: The UNT Digital Library