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N-Acylethanolamines are Metabolized by Lipoxygenase and Amidohydrolase in Competing Pathways during Cottonseed Imbibition (open access)

N-Acylethanolamines are Metabolized by Lipoxygenase and Amidohydrolase in Competing Pathways during Cottonseed Imbibition

Article on N-acylethanolamines metabolizing by lipoxygenase and amidohydrolase in competing pathways during cottonseed inbibition.
Date: September 2002
Creator: Shrestha, Rhidaya; Noordermeer, Minke A.; Van der Stelt, Marcelis; Veldink, Gerrit A. & Chapman, Kent D.
System: The UNT Digital Library
Analysis of flow behavior in fractured lithophysal reservoirs (open access)

Analysis of flow behavior in fractured lithophysal reservoirs

This study develops a mathematical model for the analysis of pressure behavior in fractured lithophysal reservoirs. The lithophysal rock is described as a tri-continuum medium, consisting of fractures, rock matrices, and cavities. In the conceptual model, fractures have homogeneous properties throughout and interact with rock matrices and cavities that have different permeabilities and porosities. Global flow occurs through the fracture network only, while rock matrices and cavities contain the majority of fluid storage and provide fluid drainage to the fractures. Interporosity flows between the triple media are described using a pseudosteady-state concept and the system is characterized by interporosity transmissivity ratios and storativity ratio of each continuum. Pressure behavior is analyzed by examining the pressure drawdown curves, the derivative plots, and the effects of the characteristic parameters. Typical pressure responses from fractures, matrices, and cavities are represented by three semilog straight lines; the transitions by two troughs below the stabilization lines in the derivative plots. The analytical solution to the proposed model is further verified using a numerical simulation. The analytical model has also been applied to a published field-buildup well test and is able to match the pressure buildup data.
Date: September 1, 2002
Creator: Liu, Jianchun; Bodvarsson, G.S. & Wu, Yu-Shu
System: The UNT Digital Library
Calibration of Yucca Mountain unsaturated zone flow and transport model using porewater chloride data (open access)

Calibration of Yucca Mountain unsaturated zone flow and transport model using porewater chloride data

In this study, porewater chloride data from Yucca Mountain, Nevada, are analyzed and modeled by 3-D chemical transport simulations and analytical methods. The simulation modeling approach is based on a continuum formulation of coupled multiphase fluid flow and tracer transport processes through fractured porous rock, using a dual-continuum concept. Infiltration-rate calibrations were using the pore water chloride data. Model results of chloride distributions were improved in matching the observed data with the calibrated infiltration rates. Statistical analyses of the frequency distribution for overall percolation fluxes and chloride concentration in the unsaturated zone system demonstrate that the use of the calibrated infiltration rates had insignificant effect on the distribution of simulated percolation fluxes but significantly changed the predicated distribution of simulated chloride concentrations. An analytical method was also applied to model transient chloride transport. The method was verified by 3-D simulation results as able to capture major chemical transient behavior and trends. Effects of lateral flow in the Paintbrush nonwelded unit on percolation fluxes and chloride distribution were studied by 3-D simulations with increased horizontal permeability. The combined results from these model calibrations furnish important information for the UZ model studies, contributing to performance assessment of the potential repository.
Date: September 1, 2002
Creator: Liu, Jianchun; Sonnenthal, Eric L. & Bodvarsson, Gudmundur S.
System: The UNT Digital Library
COMPREHENSIVE GYROKINETIC SIMULATION OF TOKAMAK TURBULENCE AT FINITE RELATIVE GYRORADIUS (open access)

COMPREHENSIVE GYROKINETIC SIMULATION OF TOKAMAK TURBULENCE AT FINITE RELATIVE GYRORADIUS

OAK B202 COMPREHENSIVE GYROKINETIC SIMULATION OF TOKAMAK TURBULENCE AT FINITE RELATIVE GYRORADIUS. A continuum global gyrokinetic code GYRO has been developed to comprehensively simulate turbulent transport in actual experimental profiles and allow direct quantitative comparisons to the experimental transport flows. GYRO not only treats the now standard ion temperature gradient (ITG) mode turbulence, but also treats trapped and passing electrons with collisions and finite beta, and all in real tokamak geometry. Most importantly the code operates at finite relative gyroradius ({rho}*) so as to treat the profile shear stabilization effects which break gyroBohm scaling. The code operates in a cyclic flux tube limit which allows only gyroBohm scaling and a noncyclic radial annulus with physical profile variation. The later requires an adaptive source to maintain equilibrium profiles. Simple ITG simulations demonstrate the broken gyroBohm scaling depends on the actual rotational velocity shear rates competing with mode growth rates, direct comprehensive simulations of the DIII-D {rho}*-scaled L-mode experiments are presented as a quantitative test of gyrokinetics and the paradigm.
Date: September 1, 2002
Creator: Waltz, R. E.; Candy, J. & Rosenbluth, M. N.
System: The UNT Digital Library
A concentration rebound method for measuring particle penetrationand deposition in the indoor environment (open access)

A concentration rebound method for measuring particle penetrationand deposition in the indoor environment

Continuous, size resolved particle measurements were performed in two houses in order to determine size-dependent particle penetration and deposition in the indoor environment. The experiments consisted of three parts: (1) measurement of the particle loss rate following artificial elevation of indoor particle concentrations, (2) rapid reduction in particle concentration through induced ventilation by pressurization of the houses with HEPA-filtered air, and (3) measurement of the particle concentration rebound after house pressurization stopped. During the particle concentration decay period, when indoor concentrations are very high, losses due to deposition are large compared to gains due to particle infiltration. During the concentration rebound period, the opposite is true. The large variation in indoor concentration allows the effects of penetration and deposition losses to be separated by the transient, two-parameter model we employed to analyze the data. We found penetration factors between 0.3 and 1 and deposition loss rates between 0.1 and 5 h{sup -1}, for particles between 0.1 and 10 {micro}m.
Date: September 1, 2002
Creator: tlthatcher@lbl.gov
System: The UNT Digital Library
Configuring load as a resource for competitive electricity markets--Review of demand response programs in the U.S. and around the world (open access)

Configuring load as a resource for competitive electricity markets--Review of demand response programs in the U.S. and around the world

The restructuring of regional and national electricity markets in the U.S. and around the world has been accompanied by numerous problems, including generation capacity shortages, transmission congestion, wholesale price volatility, and reduced system reliability. These problems have created new opportunities for technologies and business approaches that allow load serving entities and other aggregators to control and manage the load patterns of wholesale and retail end-users they serve. Demand Response Programs, once called Load Management, have re-emerged as an important element in the fine-tuning of newly restructured electricity markets. During the summers of 1999 and 2001 they played a vital role in stabilizing wholesale markets and providing a hedge against generation shortfalls throughout the U.S.A. Demand Response Programs include ''traditional'' capacity reservation and interruptible/curtailable rates programs as well as voluntary demand bidding programs offered by either Load Serving Entities (LSEs) or regional Independent System Operators (ISOs). The Lawrence Berkeley National Lab (LBNL) has been monitoring the development of new types of Demand Response Programs both in the U.S. and around the world. This paper provides a survey and overview of the technologies and program designs that make up these emerging and important new programs.
Date: September 1, 2002
Creator: Heffner, Grayson C.
System: The UNT Digital Library
Conservation in California during the summer of 2001 (open access)

Conservation in California during the summer of 2001

The goal of this study is to measure the results of energy-conservation, energy-efficiency, and load-reduction measures in the California Independent System Operator (CAISO) region during the summer of 2001. During the period leading up to summer 2001, California experienced power outages and unprecedented instability in electricity and natural gas markets. Expecting that warm summer temperatures would exacerbate the already unstable energy market, state agencies and utilities created conservation and load-reduction programs that included advertisements and publicity, bill discounts for decreased customer electricity use, and financial payments for real-time load interruptions. Because the state avoided major electricity grid disturbances during the summer, few of the load-reduction programs were tested; however, the conservation and energy-efficiency programs appear to have been quite effective. The purpose of this study is to determine the extent to which electricity loads decreased in summer 2001 relative to summer 2000 and summer 1999, independent of differences in weather patterns. Our assumption is that the portion of load reduction that is not attributable to weather can be attributed to energy-efficiency and conservation measures. To determine the load reduction, we adjusted year 1999 and year 2000 hourly loads to simulate what load would have been under year 2001 weather conditions …
Date: September 1, 2002
Creator: Bartholomew, Emily S.; Van Buskirk, Robert D. & Marnay, Chris
System: The UNT Digital Library
Construction of the WSU Epithermal Neutron Filter (open access)

Construction of the WSU Epithermal Neutron Filter

Moderating material has been installed in the original thermal-neutron filter region of the Washington State University (WSU) TRIGA™ type reactor to produce an epithermal-neutron beam. Attention has been focused upon the development of a convenient, local, epithermal-neutron beam facility at WSU for collaborative Idaho National Engineering and Environmental Laboratory (INEEL)/WSU boron neutron capture therapy (BNCT) preclinical research and boronated pharmaceutical screening in cell and animal models. The design of the new facility was performed in a collaborative effort1,2 of WSU and INEEL scientists. This paper summarizes the physical assembly of this filter.
Date: September 1, 2002
Creator: Venhuizen, James Robert; Nigg, David Waler & Tripard, G.
System: The UNT Digital Library
The Contribution of Locally Grown Foods in Cumulative Exposure Assessments (open access)

The Contribution of Locally Grown Foods in Cumulative Exposure Assessments

None
Date: September 1, 2002
Creator: Bodnar, Agnes B.; Maddalena, Randy L. & McKone, Thomas E.
System: The UNT Digital Library
Correlation of H-Mode Barrier Width and Neutral Penetration Length (open access)

Correlation of H-Mode Barrier Width and Neutral Penetration Length

OAK A271 CORRELATION OF H-MODE BARRIER WIDTH AND NEUTRAL PENETRATION LENGTH. Pedestal studies in DIII-D find a good correlation between the width of the H-mode density barrier and the neutral penetration length. These results are obtained by comparing experimental density profiles to the predictions of an analytic model for the profile, obtained from the particle continuity equations for electrons and deuterium atoms. In its range of validity (edge temperature between 40-500 eV), the analytic model quantitatively predicts the observed decrease of the width as the pedestal density increases, the observed strong increase of the gradient of the density as the pedestal density increases and the observation that L-mode and H-mode profiles with the same pedestal density have very similar shapes. The width of the density barrier, measured from the edge of the electron temperature barrier, is the lower limit for the observed width of the temperature barrier. These results support the hypothesis that particle fueling provides the dominant control for the size of the H-mode transport barrier.
Date: September 1, 2002
Creator: Groebner, R. J.; Mahdavi, M. A.; Leonard, A. W.; Osborne, T. H.; Wolf, N. S.; Porter, G. D. et al.
System: The UNT Digital Library
Correlation of H-Mode Barrier Width and Neutral Pentration Length (open access)

Correlation of H-Mode Barrier Width and Neutral Pentration Length

OAK A271 CORRELATION OF H-MODE BARRIER WIDTH AND NEUTRAL PENTRATION LENGTH. Pedestal studies in DIII-D find a good correlation between the width of the region of steep gradient in the H-mode density and the neutral penetration length. These results are obtained by comparing experimental density profiles to the predictions of an analytic model for the profile, obtained from the particle continuity equations for electrons and deuterium atoms. In its range of validity (edge temperature between 40-500 eV), the analytic model quantitatively predicts the observed decrease of the width as the pedestal density increases, the observed strong increase of the gradient of the density as the pedestal density increases and the observation that L-mode and H-mode profiles with the same pedestal density have very similar shapes. The width of the density barrier, measured from the edge of the electron temperature barrier, is the lower limit for the observed width of the temperature barrier. These results support the hypothesis that particle fueling provides a dominant control for the size of the H-mode transport barrier.
Date: September 1, 2002
Creator: Groebner, R. J.; Mahdavi, M. A.; Leonard, A. W.; Osborne, T. H.; Wolf, N. S.; Porter, G. D. et al.
System: The UNT Digital Library
A CREDIBLE PATHWAY FOR HEAY ION DRIVEN TARGET FABRICATION AND INJECTION (open access)

A CREDIBLE PATHWAY FOR HEAY ION DRIVEN TARGET FABRICATION AND INJECTION

A261. A CREDIBLE PATHWAY FOR HEAY ION DRIVEN TARGET FABRICATION AND INJECTION
Date: September 1, 2002
Creator: GOODIN, D. T.; NOBILE, A.; ALEXANDER, N.B.; BROWN, L.C.; MAXWELL, J.L.; PULSIFER, J. et al.
System: The UNT Digital Library
Development of discrete flow paths in unsaturated fractures at Yucca Mountain (open access)

Development of discrete flow paths in unsaturated fractures at Yucca Mountain

We have carried out numerical modeling studies to investigate the development of discrete fracture flow paths and flow-focusing phenomena in the unsaturated rock of the potential repository horizon at Yucca Mountain, Nevada. These studies are based on two- and three dimensional (2-D and 3-D) numerical models using site-specific parameters. The 2-D and 3-D models use high-resolution spatial discretization to explicitly include effects of discrete fractures with stochastically developed fracture permeabilities and a continuum approach. The permeability field is generated based on air-permeability measurements at various scales. For most of the cases considered, uniform infiltration with different average rates (1 to 500 mm/yr) is prescribed at the top of the model, while variability in outflow at the bottom of the model is used to evaluate the degree of flow focusing. In addition, scenarios involving nonuniform infiltration at the top boundary, different permeability correlation lengths, and different flow-allocation schemes were analyzed. The modeling results obtained from all of the cases showed a remarkably similar flow-focusing pattern at the repository horizon. Furthermore, tracer transport simulation results also revealed additional features of focused flow and transport through the fracture network.
Date: September 1, 2002
Creator: Bodvarsson, G.S.; Wu, Yu-Shu & Zhang, Keni
System: The UNT Digital Library
Electromagnetic and Weak transitions in light nuclei (open access)

Electromagnetic and Weak transitions in light nuclei

Recent advances in the study of the p -- d radiative and mu -- {sup 3}He weak capture processes by our group are presented and discussed. The trinucleon bound and scattering states have been obtained from variational calculations by expanding the corresponding wave functions in terms of correlated hyper-spherical harmonic functions. The electromagnetic and weak transition currents include one- and two-body operators. The accuracy achieved in these calculations allows for interesting comparisons with experimental data.
Date: September 1, 2002
Creator: Viviani, M.; Marcucci, L.E.; Kievsky, A.; Rosati, S. & Schiavilla, R.
System: The UNT Digital Library
Energy-weighted sum rules, y-scaling and duality (open access)

Energy-weighted sum rules, y-scaling and duality

The phenomena of scaling and Bloom-Gilman duality are examined in the context of simple nonrelativistic and relativistic quantum mechanical models. These models are shown to scale and to show the qualitative feature of Bloom-Gilman duality. This suggests that these phenomena do not necessarily require the properties of QCD.
Date: September 1, 2002
Creator: Orden, J. Wallace Van & Jeschonnek, Sabine
System: The UNT Digital Library
Evaluation of a semi-implicit numerical algorithm for a rate-dependent ductile failure model. (open access)

Evaluation of a semi-implicit numerical algorithm for a rate-dependent ductile failure model.

A survey conducted in the mid-80's revealed that the mathematical descriptions of ductile fracture tended to apply to either tensile tests or spa11 tests. The objective behind the development of the TEPLA was then a unification of these disparate phenomena into a single model.
Date: September 1, 2002
Creator: Zocher, M. A. (Marvin Anthony); Zuo, Q. K. (Qiuhai K.) & Mason, T. A. (Thomas A.)
System: The UNT Digital Library
Evaluation of the Impact of Off-Design Operation on an Air-Cooled Binary Power Plant (open access)

Evaluation of the Impact of Off-Design Operation on an Air-Cooled Binary Power Plant

Geothermal power plants are designed and constructed to provide a rated power output at specific resource and ambient conditions. Due to both diurnal and seasonal changes in the ambient air temperature, as well as a decline in resource productivity over time, plants seldom operate at these "design" conditions. This paper examines the impact of "off- design" operation of an air-cooled binary geothermal power plant. An available energy analysis is used to evaluate operation at these conditions. This evaluation identifies those portions of the power cycle that are most sensitive to changing resource and ambient conditions, as well as where improvements in cycle component or system performance would have the largest impact in increasing power output.
Date: September 1, 2002
Creator: Mines, Gregory Lee
System: The UNT Digital Library
Evolution of the unsaturated zone testing at Yucca Mountain (open access)

Evolution of the unsaturated zone testing at Yucca Mountain

The evaluation of the Yucca Mountain site has evolved from intensive surface based investigations in the early 1980s to current focus on testing in underground drifts. Different periods of site-characterization activities and prominent issues concerning the unsaturated zone are summarized. Data-collection activities have evolved from mapping of faults and fractures, to estimation of percolation through tuff layers, and to quantification of seepage into drifts. Evaluation of discrete flow paths in drifts has led to fracture-matrix interaction and matrix diffusion tests over different scales. The effects of tuff interfaces and local faults are evaluated in fractured-welded and porous-nonwelded units. Mobilization of matrix water and redistribution of moisture are measured in thermal tests. Lessons learned from underground tests are used to focus on processes needed for additional quantification. Migration through the drift shadow zone and liquid flow through faults are two important issues that have evolved from current knowledge.
Date: September 1, 2002
Creator: Wang, J.S.Y. & Bodvarsson, G.S.
System: The UNT Digital Library
Flow and transport in the drift shadow in a dual-continuum model (open access)

Flow and transport in the drift shadow in a dual-continuum model

The current concept for high-level radioactive waste disposal at Yucca Mountain is for the waste to be placed in underground tunnels (or drifts) in the middle of a thick unsaturated zone. Flow modeling and field testing have shown that not all flow encountering a drift will seep into the drift. The underlying reason for the diversion of unsaturated flow around a drift is that capillary forces in the fractures and matrix prevent water entry into the drift unless the capillary pressure in the rock decreases sufficiently to allow for gravity forces to overcome the capillary barrier. As a result of the capillary barrier effect, flow tends to be diverted around the drift, affecting the flow pattern beneath the drift. For some distance beneath the drift, water saturation and flux are reduced. This drift shadow zone is much more pronounced in the fractures than in the matrix due to dominance of gravity over capillary forces in the fractures. Moving downward, away from the drift, the shadow zone asymptotically re-equilibrates to the undisturbed flow conditions due to capillary forces. The behavior of radionuclide transport in this zone of reduced flow is investigated here because this will affect the amount of time required …
Date: September 1, 2002
Creator: Houseworth, J.E.; Finsterle, S. & Bodvarsson, G.S.
System: The UNT Digital Library
Fluid Flow and Reactive Transport Around Potential Nuclear Waste Emplacement Tunnels at Yucca Mountain, Nevada (open access)

Fluid Flow and Reactive Transport Around Potential Nuclear Waste Emplacement Tunnels at Yucca Mountain, Nevada

The evolution of fluid chemistry and mineral alteration around a potential waste emplacement tunnel (drift) is evaluated using numerical modeling. The model considers the flow of water, gas, and heat, plus reactions between minerals, CO{sub 2} gas, and aqueous species, and porosity permeability-capillary pressure coupling for a dual permeability (fractures and matrix) medium. Two possible operating temperature modes are investigated: a ''high-temperature'' case with temperatures exceeding the boiling point of water for several hundred years, and a ''low-temperature'' case with temperatures remaining below boiling for the entire life of the repository. In both cases, possible seepage waters are characterized by dilute to moderate salinities and mildly alkaline pH values. These trends in fluid composition and mineral alteration are controlled by various coupled mechanisms. For example, upon heating and boiling, CO{sub 2} exsolution from pore waters raises pH and causes calcite precipitation. In condensation zones, this CO{sub 2} redissolves, resulting in a decrease in pH that causes calcite dissolution and enhances feldspar alteration to clays. Heat also enhances dissolution of wallrock minerals leading to elevated silica concentrations. Amorphous silica precipitates through evaporative concentration caused by boiling in the high-temperature case, but does not precipitate in the low-temperature case. Some alteration of …
Date: September 1, 2002
Creator: Spycher, N. F.; Sonnenthal, E. L. & Apps, J. A.
System: The UNT Digital Library
Geothermal Access to Federal and Tribal Lands: A Progress Report; Preprint (open access)

Geothermal Access to Federal and Tribal Lands: A Progress Report; Preprint

This paper traces the progress to date in resolving key barriers to geothermal energy use. It focuses primarily on two areas: improving geothermal access to federal lands and increasing understanding of the tribal aspects of geothermal use.
Date: September 1, 2002
Creator: Farhar, B. C.
System: The UNT Digital Library
Hard Pion Electroproduction at Medium Energies (open access)

Hard Pion Electroproduction at Medium Energies

Even at moderate energy machines, there is a regime where hard pion electroproduction proceeds by a perturbatively calculable process. The process, they claim, is not the leading twist fragmentation one but rather a higher twist process that produces kinematically isolated pions. Semiexclusive data may teach us more about parton distribution functions of the target and the pion distribution amplitude. In addition, there is a connection to generalized parton distribution calculations of exclusive processes in that the perturbative kernel is the same. The subject of this report is semiexclusive photoproduction of hard pions, and the semiexclusive deep inelastic scattering version of the same, e + p {yields} e + {pi} + X, which we can also write as p(e,e{prime}{prime})X. The authors are interested in pions with large transverse momentum (that is what ''hard'' means), and particularly in pions that are kinematically isolated, rather than pions that are part of a jet. And further, they shall hope to isolate processes that can be calculated perturbatively using Quantum Chromodynamics (QCD).
Date: September 1, 2002
Creator: Afanasev, Andrei & Carlson, Carl E.
System: The UNT Digital Library
Hardware and Software Upgrades to DIII-D Main Computer Control System (open access)

Hardware and Software Upgrades to DIII-D Main Computer Control System

The complexities of monitoring and controlling the various DIII-D tokamak systems have always required the aid of high-speed computer resources. Because of recent improvements in computing technology, DIII-D has upgraded both hardware and software for the central DIII-D control system. This system is responsible for coordination of all main DIII-D subsystems during a plasma discharge. The replacement of antiquated older hardware has increased reliability and reduced costs both in the initial procurement and eventual maintenance of the system. As expected, upgrading the corresponding computer software has become the more time consuming and expensive part of this upgrade. During this redesign, the main issues focused on making the most of existing in-house codes, speed with which the new system could be brought on-line, the ability to add new features/enhancements, ease of integration with all DIII-D systems and future portability/upgrades. The resulting system has become a template by which other DIII-D systems can follow during similar upgrade paths; in particular DIII-D's main data acquisition system and neutral beam injection (NBI).
Date: September 1, 2002
Creator: Piglowski, D. A.; Penaflor, B. G.; McHarg, B. B., Jr.; Greene, K. L.; Coon, R. M. & Phillips, J. C.
System: The UNT Digital Library
A High-Resolution Aeromagnetic Survey to Identify Buried Faults at Dixie Valley, Nevada (open access)

A High-Resolution Aeromagnetic Survey to Identify Buried Faults at Dixie Valley, Nevada

Preliminary results from a high-resolution aeromagnetic survey (200m line spacing) acquired in Dixie Valley early in 2002 provide confirmation of intra-basin faulting based on subtle surface indications. In addition the data allow identification of the locations and trends of many faults that have not been recognized at the surface, and provide a picture of intrabasin faulting patterns not possible using other techniques. The data reveal a suite of northeasterly-trending curving and branching faults that surround a relatively coherent block in the area of Humboldt Salt Marsh, the deepest part of the basin. The producing reservoir occurs at the north end of this coherent block, where rampart faults from the northwest side of the valley merge with anthithetic faults from the central and southeast parts of the valley.
Date: September 1, 2002
Creator: Smith, Richard Paul; Grauch, V. J. S. & Blackwell, David D.
System: The UNT Digital Library