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Seismic Absorption and Modulus Measurements in Porous Rocks in Lab and Field: Physical, Chemical, and Biological Effects of Fluids (Detecting a Biosurfactant Additive in a Field Irrigation Experiment)

Description: We have been exploring a new technology that is based on using low-frequency seismic attenuation data to monitor changes in fluid saturation conditions in two-fluid phase porous materials. The seismic attenuation mechanism is related to the loss of energy due to the hysteresis of resistance to meniscus movement (changes in surface tension, wettability) when a pore containing two fluids is stressed at very low frequencies (< 10 Hz). This technology has potential applications to monitoring cha… more
Date: May 1, 2006
Creator: Spetzler, Hartmut
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Collaborative Research: Towards Advanced Understanding and Predictive Capability of Climate Change in the Arctic Using a High-Resolution Regional Arctic Climate Model

Description: The primary research task completed for this project was the development of the Regional Arctic Climate Model (RACM). This involved coupling existing atmosphere, ocean, sea ice, and land models using the National Center for Atmospheric Research (NCAR) Community Climate System Model (CCSM) coupler (CPL7). RACM is based on the Weather Research and Forecasting (WRF) atmospheric model, the Parallel Ocean Program (POP) ocean model, the CICE sea ice model, and the Variable Infiltration Capacity (VIC)… more
Date: June 30, 2013
Creator: Cassano, John
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Improved Transport Processes for CCSM

Description: In atmospheric modeling, global spectral methods have dominated weather and climate simulation for the past two decades. However, global methods based upon the spherical harmonic basis functions require expensive non-local communication and thus have difficulty in exploiting the full potential of current high-performance parallel computers. The primary objective of HOMME ((11)) is the development of a class of high-order scalable conservative atmospheric models for climate and general atmospher… more
Date: May 5, 2011
Creator: Tufo, Henry
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Solar-thermal Water Splitting Using the Sodium Manganese Oxide Process & Preliminary H2A Analysis

Description: There are three primary reactions in the sodium manganese oxide high temperature water splitting cycle. In the first reaction, Mn2O3 is decomposed to MnO at 1,500°C and 50 psig. This reaction occurs in a high temperature solar reactor and has a heat of reaction of 173,212 J/mol. Hydrogen is produced in the next step of this cycle. This step occurs at 700°C and 1 atm in the presence of sodium hydroxide. Finally, water is added in the hydrolysis step, which removes NaOH and regenerates the orig… more
Date: October 24, 2012
Creator: Francis, Todd M.; Lichty, Paul R.; Perkins, Christopher; Tucker, Melinda; Kreider, Peter B.; Funke, Hans H. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Validation of Numerical Two-Fluid and Kinetic Plasma Models

Description: This was a four year grant commencing October 1, 2003 and finishing September 30, 2007. The funding was primarily used to support the work of the Principal Investigator, who collaborated with Profs. Scott Parker and John Cary at U. Colorado, and with two students, N. Xiang and J. Cheng also of U. Colorado. The technical accomplishments of this grant can be found in the publications listed in the final Section here. The main accomplishments of the grant work were: (1) Development and implementat… more
Date: March 25, 2011
Creator: Barnes, Daniel
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Integrated Multiscale Modeling of Molecular Computing Devices

Description: Significant advances were made on all objectives of the research program. We have developed fast multiresolution methods for performing electronic structure calculations with emphasis on constructing efficient representations of functions and operators. We extended our approach to problems of scattering in solids, i.e. constructing fast algorithms for computing above the Fermi energy level. Part of the work was done in collaboration with Robert Harrison and George Fann at ORNL. Specific results… more
Date: March 23, 2012
Creator: Beylkin, Gregory
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Regional-Scale Climate Change: Observations and Model Simulations

Description: This collaborative proposal addressed key issues in understanding the Earth’s climate system, as highlighted by the U.S. Climate Science Program. The research focused on documenting past climatic changes and on assessing future climatic changes based on suites of global and regional climate models. Geographically, our emphasis was on the mountainous regions of the world, with a particular focus on the Neotropics of Central America and the Hawaiian Islands. Mountain regions are zones where lar… more
Date: December 14, 2010
Creator: Bradley, Raymond S. & Diaz, Henry F.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
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Plasma Simulation Using Gyrokinetic-Gyrofluid Hybrid Models

Description: We are developing kinetic ion models for the simulation of extended MHD phenomena. The model they have developed uses full Lorentz force ions, and either drift-kinetic or gyro-kinetic electrons. Quasi-neutrality is assumed and the displacement current is neglected. They are also studying alpha particle driven Toroidal Alfven Eigenmodes (TAE) in the GEM gyrokinetic code [Chen 07]. The basic kinetic ion MHD model was recently reported in an invited talk given by Dan Barnes at the 2007 American Ph… more
Date: April 9, 2009
Creator: Parker, Scott
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Highly Selective H2 Separation Zeolite Membranes for Coal Gasification Membrane Reactor Applications

Description: Zeolite membranes are thermally, chemically, and mechanically stable. They also have tunable molecular sieving and catalytic ability. These unique properties make zeolite membrane an excellent candidate for use in catalytic membrane reactor applications related to coal conversion and gasification, which need high temperature and high pressure range separation in chemically challenging environment where existing technologies are inefficient or unable to operate. Small pore, good quality, and thi… more
Date: September 24, 2007
Creator: Hong, Mei; Noble, Richard & Falconer, John
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Final Technical Report

Description: Installation of new Shortwave Spectrometer for permanent operation at SGP - In May 2006 the new ShortWave Spectrometer (SWS) was installed in the Optical Trailer at the Southern Great Plains Central Facility SGP on 27 April 2006. The SWS began full operation 28 April 2006 and has run continuously to the present. Over 25 GB of spectra has been collected, calibrated and archived. 3-D radiative transfer simulations - Retrieved fields of cloud optical thickness and effective radius to from the MODI… more
Date: May 26, 2009
Creator: Pilewskie, Peter
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Accounting for Unresolved Spatial Variability in Large Scale Models: Development and Evaluation of a Statistical Cloud Parameterization with Prognostic Higher Order Moments

Description: This project focused on the variability of clouds that is present across a wide range of scales ranging from the synoptic to the millimeter. In particular, there is substantial variability in cloud properties at scales smaller than the grid spacing of models used to make climate projections (GCMs) and weather forecasts. These models represent clouds and other small-scale processes with parameterizations that describe how those processes respond to and feed back on the largescale state of the at… more
Date: May 17, 2011
Creator: Pincus, Robert
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Highly Selective H2 Separation Zeolite Membranes for Coal Gasification Membrane Reactor Applications

Description: Zeolite membranes are thermally, chemically, and mechanically stable. They also have tunable molecular sieving and catalytic ability. These unique properties make zeolite membrane an excellent candidate for use in catalytic membrane reactor applications related to coal conversion and gasification, which need high temperature and high pressure range separation in chemically challenging environment where existing technologies are inefficient or unable to operate. Small pore, good quality, and thi… more
Date: September 24, 2006
Creator: Hong, Mei; Noble, Richard D. & Falconer, John L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Advanced Conceptual Models for Unsaturated and Two-Phase Flow in Fractured Rock

Description: The Department of Energy Environmental Management Program is faced with two major issues involving two-phase flow in fractured rock; specifically, transport of dissolved contaminants in the Vadose Zone, and the fate of Dense Nonaqueous Phase Liquids (DNAPLs) below the water table. Conceptual models currently used to address these problems do not correctly include the influence of the fractures, thus leading to erroneous predictions. Recent work has shown that it is crucial to understand the top… more
Date: June 1, 2004
Creator: Nicholl, Michael J.; Glass, Robert J.; Rajaram, Harihar & Wood, Thomas R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Reactivity of Primary Soil Minerals and Secondary Precipitates beneath Leaking Hanford Waste Tanks

Description: Since the late 1950s, leaks from 67 single-shell tanks at the Hanford Site have released about 1 million curies to the underlying sediments. At issue is the distribution of contaminants beneath the tanks, and the processes that led to their current disposition and will control their future mobility. The high ionic strength, high pH, and high aluminum concentrations in the tank liquids can significantly alter the vadose zone sediments through dissolution of primary minerals and precipitation of … more
Date: June 1, 2001
Creator: Nagy, Kathryn L.; Serne, R. Jeff & Yabusaki
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Influences of Flow Transients and Porous Medium Heterogeneity on Colloid-Associated Contaminant Transport in the Vadose Zone

Description: We are investigating the role of colloids in the movement of radionuclides through water unsaturated porous media. This research is guided by a key objective of the Environmental Management Science Program (EMSP), which is to improve conceptual and predictive models for contaminant movement in complex vadose zone environments. In the report entitled National Roadmap for Vadose Zone Science and Technology [DOE, 2001], increases in the understanding of colloid-contaminant interactions, colloid mo… more
Date: June 1, 2003
Creator: Saiers, James & Ryan, Joseph
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Annual Scientific Report for DE-FG03-02NA00063 Coherent imaging of laser-plasma interactions using XUV high harmonic radiation

Description: In this project, we use coherent short-wavelength light generated using high-order harmonic generation as a probe of laser-plasma dynamics and phase transitions on femtosecond time-scales. The interaction of ultrashort laser pulses with materials and plasmas is relevant to stockpile stewardship, to understanding the equation of state of matter at high pressures and temperatures, and to plasma concepts such as the fast-ignitor ICF fusion concept and laser-based particle acceleration. Femtosecond… more
Date: May 3, 2005
Creator: Kapteyn, Prof. Henry C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Advanced Conceptual Models for Unsaturated and Two-Phase Flow in Fractured Rock

Description: The Department of Energy Environmental Management Program is faced with two major issues involving two-phase flow in fractured rock; specifically, transport of dissolved contaminants in the Vadose Zone, and the fate of Dense Nonaqueous Phase Liquids (DNAPLs) below the water table. Conceptual models currently used to address these problems do not correctly include the influence of the fractures, thus leading to erroneous predictions. Recent work has shown that it is crucial to understand the top… more
Date: June 2003
Creator: Nicholl, Michael J.; Glass, Robert J.; Rajaram, Harihar & Wood, Thomas R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Aspects of C-H Activation in Metal Complexes Containing Sulfur Ligands

Description: The research project proposed to synthesize new metal complexes with sulfido, disulfido and other types of reactive sulfur ligands, and to explore the joint reactivity of metal and sulfur ligands with hydrogen and organic molecules. The overall objective was to investigate reaction pathways relevant to those observed for the heterogeneous metal sulfide catalysts which promote hydrogen activation, hydrogenation-dehydrogenation of organic substrates, and hydrogenolysis of carbon-heteroatom bonds.… more
Date: October 8, 2004
Creator: Rakowski-DuBois, Mary C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theoretical and Experimental Studies of Hydrological Properties of Rock Features During Active Deformation

Description: The objective of this project is to investigate the transport characteristics of variable aperture fractures. They employed laboratory experiments and numerical modeling to study the transport characteristics of variable aperture fractures. They developed a new model describing the permeability of variable aperture fractures. Using a Lattice Boltzmann numerical model, they investigate the dispersion coefficient in non-Darcian regime of a natural fracture with multi solutes.
Date: February 24, 2003
Creator: Ge, Dr. Shemin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Exploring Quantum Degenerate Bose-Fermi Mixtures Toward Cooper Pairing of Fermionic Atoms

Description: We have been exploring interaction dynamics in an ultracold, trapped gas of bosonic and fermionic atoms. Investigation of this new class of quantum degenerate gases concentrates on interaction dominated phenomena such as sympathetic cooling, phase separation, excitations, Feshbach resonances, and the effects of quantum degeneracy. In addition to exploring these new phenomena, we seek to understand and ultimately control the interactions in the gas. In particular, effective interactions between … more
Date: April 20, 2011
Creator: Jin, Deborah
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Development, Verification, and Validation of Multiphase Models for Polydisperse Flows

Description: This report describes in detail the technical findings of the DOE Award entitled 'Development, Verification, and Validation of Multiphase Models for Polydisperse Flows.' The focus was on high-velocity, gas-solid flows with a range of particle sizes. A complete mathematical model was developed based on first principles and incorporated into MFIX. The solid-phase description took two forms: the Kinetic Theory of Granular Flows (KTGF) and Discrete Quadrature Method of Moments (DQMOM). The gas-soli… more
Date: December 31, 2011
Creator: Hrenya, Christine; Cocco, Ray; Fox, Rodney; Subramaniam, Shankar & Sundaresan, Sankaran
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development and application of new methods to retrieve vertical structure of precipitation above the ARM CART sites from MMCR measurements

Description: The main objective of this project was to develop, validate and apply remote sensing methods to retrieve vertical profiles of precipitation over the DOE ARM CART sites using currently available remote sensors. While the ARM Program invested very heavily into developments of remote sensing methods and instruments for water vapor and non-precipitating cloud parameter retrievals, precipitation retrievals and studies lagged behind. Precipitation, however, is a crucial part of the water cycle, and w… more
Date: December 15, 2010
Creator: Matrosov, Dr. Sergey
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Final report for grant DE-FG02-06ER64182: "Evaluation and Improvement of the Cloud Resolving Model Component of the Multi-Scale Modeling Framework"

Description: The overall aim of the larger collaborative effort of which this project was part was to evaluate and improve the cloud system resolving model (CSRM) at the heart of the multi-scale modeling framework (MMF). Our task at the University of Colorado our effort was to develop methods that would let us evaluate the performance of cloud-scale models at the ARM SGP site using ARM remote sensing products.
Date: October 13, 2009
Creator: Pincus, Robert
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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