Serial/Series Title
OIT Tip Sheets
10
Establishment of an Industry-Driven Consortium Focused on Improving the Production Performance of Domestic Stripper Wells Quarterly Report
8
Fiscal Year 2004
8
Enhanced Wellbore Stabilization and Reservoir Productivity with Aphron Drilling Fluid Technology
6
Fiscal Year 2003
6
Small Wind Electric Systems Consumers' Guides
6
Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines Progress Report
4
Differential Soil Impedance Obstacle Detection Quarterly Report
4
Field Demonstration of a Membrane Process to Separate Nitrogen From Natural Gas Progress Report
4
Fundamentals of Reservoir Surface Energy as Related to Surface Properties, Wettability, Capillary Action, and Oil Recovery From Fractured Reservoirs by Spontaneous Imbibition Quarterly Report
4
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7,097
Dimensional Measurements of Three Tubes by Computed Tomography
Low density polyethylene (LDPE), copper (Cu), and gold (Au) tubes were scanned on KCAT to identify and evaluate the impact of phase effects on quantitative object recovery. These tubes are phantoms for high energy density capsules.[Logan, et al. 2004] Digital radiographs for each tube are shown in Figure 1. The LDPE tube was scanned at 60 kV, while the Cu and the Au tubes were scanned at 140 kV. All tubes were scanned at a magnification of 3, with approximately 100-mm distance between the exit plane of the tube and the scintillator. Notice the prominence of the outer bright and inner dark edges for the LDPE tube DR, and their absence from the Cu and Au tube DRs. The bright and dark edges are a result of change in phase of the x-rays. The x-ray fluence is partly attenuated and partly refracted. The location near the outer edge of the tube appears to be more attenuating since those x-rays have refracted to locations just outside the tube. Alternatively, the added counts from the refraction result in intensities that are greater than the incident intensity effectively representing a ''negative attenuation''. This results in more counts in that location than in the …
Date:
October 5, 2004
Creator:
Schneberk, D. J.; Martz, H. E., Jr. & Brown, W. D.
Object Type:
Report
System:
The UNT Digital Library
Advancing the Technology R&D of Tabletop Mesoscale Nondestructive Characterization
This Strategic Initiative (SI) will advance nondestructive characterization of mesoscale (millimeter-sized) objects--allowing micrometer resolution over the objects' entire volume. X-ray imaging will be developed that allows object characterization with materials that vary widely in composition, density, and geometry.
Date:
September 24, 2004
Creator:
Martz, H. E., Jr.; Aufderheide, M.; Barty, A.; Jackson, J. A.; Kallman, J. S.; Kozioziemski, B. et al.
Object Type:
Report
System:
The UNT Digital Library
ALS Performance Summary - Update
High Energy Density Physics (HEDP) experiments play an important role in corroborating the improved physics codes that underlie LLNL's Stockpile Stewardship mission. Conducting these experiments, whether on the National Ignition Facility (NIF) or another national facility such as Omega, will require not only improvement in the diagnostics for measuring the experiment, but also detailed knowledge of the as-built target components and assemblies themselves. To assist in this effort, a defined set of well-known reference standards designed to represent a range of HEDP targets have been built and are being used to quantify the performance of different characterization techniques [Hibbard, et al. 2004]. Without the critical step of using reference standards for qualifying characterization tools there can be no verification of either commercial or internally-developed characterization techniques and thus an uncertainty in the input to the physics code models would exist.
Date:
September 30, 2004
Creator:
Waters, A M; Brown, W D & Martz, H. E., Jr.
Object Type:
Report
System:
The UNT Digital Library
Criteria for Second Stability for Ballooning Modes in Stellarators
An expression determining how variations in the pressure-gradient and average magnetic shear affect ballooning stability for a stellarator equilibrium is presented. The procedure for determining the marginal stability boundaries, for each field line, depends only on the equilibrium and a single ballooning eigenfunction calculation. This information is sufficient to determine if increasing pressure-gradient is stabilizing or destabilizing and to predict whether the configuration possess a second stable region.
Date:
July 6, 2004
Creator:
Hudson, S. R. & Hegna, C. C.
Object Type:
Report
System:
The UNT Digital Library
Corrosion probes for fireside monitoring in coal-fired boilers
Electrochemical corrosion rate (ECR) probes were constructed and exposed along with mass loss coupons in a N2/O2/CO2/H2O environment to determine ECR probe operating characteristics. Temperatures ranged from 450 to 600 C and both ECR probes and mass loss coupons were coated with ash. Results are presented in terms of the probe response to temperature, the measured zero baseline, and the quantitative nature of the probes. The effect of Stern-Geary constant and the choice of electrochemical technique used to measure the corrosion rate are also discussed. ECR probe corrosion rates were a function of time, temperature, and process environment and were found to be quantitative for some test conditions. Measured Stern-Geary constants averaged 0.0141 V/decade and the linear polarization technique was found to be more quantitative than the electrochemical noise technique.
Date:
January 1, 2004
Creator:
Covino, Bernard S., Jr.; Bullard, Sophie J.; Cramer, Stephen D.; Holcomb, Gordon R.; Ziomek-Moroz, Margaret; Eden, David A. et al.
Object Type:
Article
System:
The UNT Digital Library
New Results with the superconducting ECR ion source VENUS
During the last year, the VENUS ECR ion source was commissioned at 18 GHz and preparations for 28 GHz operation, which is set to begin early in 2004, are now underway. The goal of the VENUS ECR ion source project as the RIA R&D injector is the production of 240emA of U30+, a high current medium charge state beam. On the other hand, as an injector ion source for the 88-Inch Cyclotron the design objective is the production of 5emA of U48+, a low current, very high charge state beam. During the commissioning phase with 18 GHz, tests with various gases and recently metals have been performed with up to 2000 W RF power and the performance is very promising. For example, 1100 e mu A of O6+,180 e mu A of Ar12+, 150 emA of Xe20+ and 100 emA of Bi24+ were produced in the early commissioning phase, ranking VENUS among the currently highest performance 18 GHz ECR ion sources. The emittance of the beams produced at 18 GHz was measured with a two axis emittance scanner. In FY04 a 10 kW, 28 GHz gyrotron system will be added, which will enable VENUS to reach full performance. The performance …
Date:
May 13, 2004
Creator:
Lyneis, C. M.; Leitner, D.; Abbott, S. R.; Dwinell, R. D.; Leitner, M.; Silver, C. S. et al.
Object Type:
Article
System:
The UNT Digital Library
DPB progress report: Hydrogen uptake capacity for a particular sample of DPB
The authors have performed hydrogen uptake to measure the remaining capacity for two DPB pellet samples. The measurements were made with a Cahn microbalance operating at room temperature. The DPB samples were placed inside a quartz boat and the microbalance was then evacuated to a base pressure of 10{sup -4} Torr overnight. This overnight pumping removed volatile contaminants from the DPB pellets prior to the introduction of 600 Torr of N{sub 2} into the microbalance chamber. Next, a leak valve connecting the microbalance with a research grade source of H{sub 2} was opened to add 100 Torr of H{sub 2} on top of the 600 Torr of N{sub 2} already in the microbalance. When the total pressure in the microbalance reached 700 Torr, the H{sub 2} leak valve was not completely shut off but reduced to a very small positive rate. An automatic gate valve connecting the microbalance to a turbo molecular pump was programmed by a controller to keep the total pressure in the microbalance at 700 {+-} 3 Torr. The balance between H{sub 2} consumption due to DPB uptake and H{sub 2} leak rate into the microbalance was such that the gate valve to the turbo molecular pump …
Date:
November 9, 2004
Creator:
Dinh, L. N.; Schildbach, M. A.; Maxwell, R. S.; Balazs, B. & McLean, W., II
Object Type:
Report
System:
The UNT Digital Library
H2O Outgassing from Silicones
In this fiscal year, we have tested the H{sub 2}O outgassing model for TR55 against independent core tests performed at different temperatures by our collaborators at Y12. At higher temperature ({approx} 71 C), the model properly predicts moisture outgassing from TR55 over the entire experiment. At lower temperature ({approx} 42.5 C), the model correctly predicts long-term moisture outgassing. However, in short-term limit, a better fit with core tests might be expected when the diffusion effect of H{sub 2}O through the silicone matrix is included into the model in the near future. A lookup table for the moisture content as well as moisture outgassing kinetics for M9787 which have previously been heated to 460K for one day and then exposed to relevant low levels of moisture is also now available as a reference for engineers/technicians in the fields.
Date:
November 9, 2004
Creator:
Dinh, L. N.; Maxwell, R. S.; Schildbach, M. A.; Balazs, B. & McLean, W., II
Object Type:
Report
System:
The UNT Digital Library
Structure, Vibrational and Electronic Spectra of Heterofullerene C48(BN)6
We report the geometrical structure, vibrational, and excitation spectra of novel, fullerene - analog C{sub 48}(BN){sub 6} using density functional calculations. The lowest energy structure is one in which B-N bonding is present as boron and nitrogen occupy each of the twelve pentagons of the fullerene cage. The cluster is polar with a net dipole moment of 0.55 Debye, which indicates an enhanced tendency toward reactivity with other media. The excitation spectrum shows that the lowest transition of 1.75 eV is dipole-allowed. The optical gap of C{sub 48}(BN){sub 6} is redshifted by 1.17 eV relative to that of C{sub 60}, suggesting possible use as single-molecule fluorescent probes for various applications.
Date:
January 15, 2004
Creator:
Manaa, M R; Xie, R & Smith, V. H., Jr.
Object Type:
Article
System:
The UNT Digital Library
Deterministic, Nanoscale Fabrication of Mesoscale Objects
Neither LLNL nor any other organization has the capability to perform deterministic fabrication of mm-sized objects with arbitrary, {micro}m-sized, 3-D features and with 100-nm-scale accuracy and smoothness. This is particularly true for materials such as high explosives and low-density aerogels, as well as materials such as diamond and vanadium. The motivation for this project was to investigate the physics and chemistry that control the interactions of solid surfaces with laser beams and ion beams, with a view towards their applicability to the desired deterministic fabrication processes. As part of this LDRD project, one of our goals was to advance the state of the art for experimental work, but, in order to create ultimately a deterministic capability for such precision micromachining, another goal was to form a new modeling/simulation capability that could also extend the state of the art in this field. We have achieved both goals. In this project, we have, for the first time, combined a 1-D hydrocode (''HYADES'') with a 3-D molecular dynamics simulator (''MDCASK'') in our modeling studies. In FY02 and FY03, we investigated the ablation/surface-modification processes that occur on copper, gold, and nickel substrates with the use of sub-ps laser pulses. In FY04, we investigated laser …
Date:
December 8, 2004
Creator:
Mariella, R., Jr.; Gilmer, J.; Rubenchik, A. & Shirk, M.
Object Type:
Report
System:
The UNT Digital Library
Deterministic, Nanoscale Fabrication of Mesoscale Objects
Neither LLNL nor any other organization has the capability to perform deterministic fabrication of mm-sized objects with arbitrary, {micro}m-sized, 3-dimensional features with 20-nm-scale accuracy and smoothness. This is particularly true for materials such as high explosives and low-density aerogels. For deterministic fabrication of high energy-density physics (HEDP) targets, it will be necessary both to fabricate features in a wide variety of materials as well as to understand and simulate the fabrication process. We continue to investigate, both in experiment and in modeling, the ablation/surface-modification processes that occur with the use of laser pulses that are near the ablation threshold fluence. During the first two years, we studied ablation of metals, and we used sub-ps laser pulses, because pulses shorter than the electron-phonon relaxation time offered the most precise control of the energy that can be deposited into a metal surface. The use of sub-ps laser pulses also allowed a decoupling of the energy-deposition process from the ensuing movement/ablation of the atoms from the solid, which simplified the modeling. We investigated the ablation of material from copper, gold, and nickel substrates. We combined the power of the 1-D hydrocode ''HYADES'' with the state-of-the-art, 3-D molecular dynamics simulations ''MDCASK'' in our studies. …
Date:
September 24, 2004
Creator:
Mariella, R., Jr.; Shirk, M; Gilmer, G & Rubenchik, A
Object Type:
Report
System:
The UNT Digital Library
Perchlorate and Nitrate Remediation Efficiency and Microbial Diversity in a Containerized Wetland Bioreactor
We have developed a method to remove perchlorate (14 to 27 {micro}g/L) and nitrate (48 mg/L) from contaminated groundwater using a wetland bioreactor. The bioreactor has operated continuously in a remote field location for more than two years with a stable ecosystem of indigenous organisms. This study assesses the bioreactor for long-term perchlorate and nitrate remediation by evaluating influent and effluent groundwater for reduction-oxidation conditions and nitrate and perchlorate concentrations. Total community DNA was extracted and purified from 10-g sediment samples retrieved from vertical coring of the bioreactor during winter. Analysis by denaturing gradient gel electrophoresis of short, 16S rDNA, polymerase-chain-reaction products was used to identify dominant microorganisms. Bacteria genera identified were closely affiliated with bacteria widely distributed in soils, mud layers, and fresh water. Of the 17 dominant bands sequenced, most were gram negative and capable of aerobic or anaerobic respiration with nitrate as the terminal electron acceptor (Pseudomonas, Acinetobacter, Halomonas, and Nitrospira). Several identified genera (Rhizobium, Acinetobactor, and Xanthomonas) are capable of fixing atmospheric nitrogen into a combined form (ammonia) usable by host plants. Isolates were identified from the Proteobacteria class, known for the ability to reduce perchlorate. Initial bacterial assessments of sediments confirm the prevalence of facultative …
Date:
June 9, 2004
Creator:
Daily, Bill, Jr.; Dibley, Valerie; Pinkart, Holly & Legler, Tina
Object Type:
Article
System:
The UNT Digital Library
Development of an Environmentally Benign Microbial Inhibitor to Control Internal Pipeline Corrosion
The overall program objective is to develop and evaluate environmentally benign agents or products that are effective in the prevention, inhibition, and mitigation of microbially influenced corrosion (MIC) in the internal surfaces of metallic natural gas pipelines. The goal is to develop one or more environmentally benign (a.k.a. ''green'') products that can be applied to maintain the structure and dependability of the natural gas infrastructure. Previous testing indicated that the growth, and the metal corrosion caused by pure cultures of sulfate reducing bacteria were inhibited by hexane extracts of some pepper plants. This quarter tests were performed to determine if chemical compounds other than pepper extracts could inhibit the growth of corrosion-associated microbes and to determine if pepper extracts and other compounds can inhibit corrosion when mature biofilms are present. Several chemical compounds were shown to be capable of inhibiting the growth of corrosion-associated microorganisms, and all of these compounds limited the amount of corrosion caused by mature biofilms to a similar extent. It is difficult to control corrosion caused by mature biofilms, but any compound that disrupts the metabolism of any of the major microbial groups present in corrosion-associated biofilms shows promise in limiting the amount/rate of corrosion.
Date:
October 30, 2004
Creator:
Bogan, Bill W.; Lamb, Brigid M. & Kilbane, John J., II
Object Type:
Report
System:
The UNT Digital Library
Development of an Environmentally Benign Microbial Inhibitor to Control Internal Pipeline Corrosion: Final Report
The overall program objective is to develop and evaluate environmentally benign agents or products that are effective in the prevention, inhibition, and mitigation of microbially influenced corrosion (MIC) in the internal surfaces of metallic natural gas pipelines. The goal is to develop one or more environmentally benign (a.k.a. ''green'') products that can be applied to maintain the structure and dependability of the natural gas infrastructure. Various chemicals that inhibit the growth and/or the metabolism of corrosion-associated microbes such as sulfate reducing bacteria, denitrifying bacteria, and methanogenic bacteria were evaluated to determine their ability to inhibit corrosion in experiments utilizing pure and mixed bacterial cultures, and planktonic cultures as well as mature biofilms. Planktonic cultures are easier to inhibit than mature biofilms but several compounds were shown to be effective in decreasing the amount of metal corrosion. Of the compounds tested hexane extracts of Capsicum pepper plants and molybdate were the most effective inhibitors of sulfate reducing bacteria, bismuth nitrate was the most effective inhibitor of nitrate reducing bacteria, and 4-((pyridine-2-yl)methylamino)benzoic acid (PMBA) was the most effective inhibitor of methanogenic bacteria. All of these compounds were demonstrated to minimize corrosion due to MIC, at least in some circumstances. The results obtained …
Date:
December 1, 2004
Creator:
Bogan, Bill W.; Lamb, Brigid M.; Husmillo, Gemma; Lowe, Kristine; Paterek, J. Robert & Kilbane, John J., II
Object Type:
Report
System:
The UNT Digital Library
Development of an Environmentally Benign Microbial Inhibitor to Control Internal Pipeline Corrosion Quarterly Report
The overall program objective is to develop and evaluate environmentally benign agents or products that are effective in the prevention, inhibition, and mitigation of microbially influenced corrosion (MIC) in the internal surfaces of metallic natural gas pipelines. The goal is to develop one or more environmentally benign (a.k.a. ''green'') products that can be applied to maintain the structure and dependability of the natural gas infrastructure. Previous testing indicated that the growth, and the metal corrosion caused by pure cultures of sulfate reducing bacteria were inhibited by hexane extracts of some pepper plants. This quarter tests were performed with mixed bacterial cultures obtained from natural gas pipelines. Treatment with the pepper extracts affected the growth and metabolic activity of the microbial consortia. Specifically, the growth and metabolism of sulfate reducing bacteria was inhibited. The demonstration that pepper extracts can inhibit the growth and metabolism of sulfate reducing bacteria in mixed cultures is a significant observation validating a key hypothesis of the project. Future tests to determine the effects of pepper extracts on mature/established biofilms will be performed next.
Date:
July 30, 2004
Creator:
Lowe, Kristine L.; Bogan, Bill W.; Sullivan, Wendy R.; Cruz, Kristine Mila H.; Lamb, Brigid M. & Kilbane, John J., II
Object Type:
Report
System:
The UNT Digital Library
Environmentally Benign Mitigation of Microbiologically Influenced Corrosion (MIC)
The overall program objective is to develop and evaluate environmentally benign agents or products that are effective in the prevention, inhibition, and mitigation of microbially influenced corrosion (MIC) in the internal surfaces of metallic natural gas pipelines. The goal is to develop one or more environmentally benign (a.k.a. ''green'') products that can be applied to maintain the structure and dependability of the natural gas infrastructure. The technical approach for this quarter included the fractionation of extracts prepared from several varieties of pepper plants, and using several solvents, by high performance liquid chromatography (HPLC). A preliminary determination of antimicrobial activities of the new extracts and fractions using a growth inhibition assay, and evaluation of the extracts ability to inhibit biofilm formation was also performed. The analysis of multiple extracts of pepper plants and fractions of extracts of pepper plants obtained by HPLC illustrated that these extracts and fractions are extremely complex mixtures of chemicals. Gas chromatography-mass spectrometry was used to identify the chemical constituents of these extracts and fractions to the greatest degree possible. Analysis of the chemical composition of various extracts of pepper plants has illustrated the complexity of the chemical mixtures present, and while additional work will be performed …
Date:
January 31, 2004
Creator:
Kilbane, John J., II & Bogan, William
Object Type:
Report
System:
The UNT Digital Library
Molecular Characterization of the Role of a Calcium Channel in Plant Development
A stimulus-induced change in cellular Ca2+ levels is a critical component of energy transduction in plant and animal development. Demonstrating Ca2+'s involvement in any developmental process requires identification of mechanisms that regulate these Ca2+ changes. In plants, biochemical studies have implicated the activity of Ca2+ channels in increases in cellular Ca2+ levels; however, molecular evidence for these transporters is lacking. Our studies used the mosses Physcomitrella patens and Funaria hygrometrica to establish a role for Ca2+ in hormone-induced morphogenesis and to use this developmental process to identify transporters responsible for increasing cytosolic Ca2+ levels. Using 1,4-dihydropyridines (DHPs), molecules that block Ca2+ movement through voltage-dependent channels in animal cells, we have shown that Ca2+ is important early in the transition from filamentous to meristematic-like growth that occurs in response to the plant hormone cytokinin. In addition to inhibiting moss growth (see below), these Ca2+ channel blockers prevent Ca2+ transport into moss cells (Schumaker and Gizinski, 1993) and bind specifically to two proteins in the moss plasma membrane (Schumaker and Gizinski, 1994; 1996; Dietrich et al., unpublished results). We used tandem mass spectrometry of the partially purified DHP-binding proteins with the goal of identifying the putative Ca2+ channel and providing sequence information …
Date:
December 21, 2004
Creator:
Schumaker, Karen S.
Object Type:
Report
System:
The UNT Digital Library