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1982 THERMAL SHALLOW RESERVOIR TESTING (open access)

1982 THERMAL SHALLOW RESERVOIR TESTING

An extensive study of the Thermal Shallow Reservoir at The Geysers was performed in 1982 to improve our understanding of the source and flow patterns of steam in the shallow anomaly and how they relate to the Thermal 4 blowout. This project included gathering and analyzing pressure transient, enthalpy, tracer and chemical data and developing a reservoir model that was consistent with this data. Following the pressure transient testing and analysis, a convection-plume with lateral-flow model was proposed. Subsequent analysis of enthalpy, tracer and chemical data corroborated this model. The high flowrate wells--Thermal 4, Thermal 10, Thermal 11 and Magma 1--produce from the high-pressure, high-permeability upflow zone. The source of this upflow is a limited fracture system connecting the shallow anomaly with the underlying main reservoir. The outlying low-pressure, low-permeability wells are supplied by lateral flow of steam from the central area. The pressure gradient from the core to the periphery is caused by condensation in the flanks.
Date: January 22, 1985
Creator: Mogen, P.; Pittinger, L. & Magers, M.
System: The UNT Digital Library
AA Fest General Circulation Model Development: Past, Present and Future. A Symposium in Honor of Professor Akio Arakawa (open access)

AA Fest General Circulation Model Development: Past, Present and Future. A Symposium in Honor of Professor Akio Arakawa

On January 20-22, 1998, ''AA Fest. A Symposium on General Circulation Model Development: Past, Present, and Future'' was held at the North West Campus Auditorium of University of California, Los Angeles, in honor of Professor Ako Arawaka. The symposium consisted of two-and-a-half-day technical presentations, along with a banquet in the opening evening and a reception during the poster session of the second evening.
Date: January 22, 1998
Creator: Ide, Kayo
System: The UNT Digital Library
Ab initio transport properties of nanostructures from maximally localized Wannier functions (open access)

Ab initio transport properties of nanostructures from maximally localized Wannier functions

Article on ab initio transport properties of nanostructures from maximally localized Wannier functions.
Date: January 22, 2004
Creator: Calzolari, Arrigo; Marzari, Nicola; Souza, Ivo & Buongiorno Nardelli, Marco
System: The UNT Digital Library
Adherence to Exercise Programs in Older Adults: Informative Report (open access)

Adherence to Exercise Programs in Older Adults: Informative Report

This article focuses on filling information gaps regarding adherence to physical activity and exercise in the health care spectrum of older adults (OA) and an overview of the benefits of physical activity for OA. Exercise adherence in OA is a multifactorial problem encompassing many biopsychosocial factors. Factors affecting adherence in the OA include socioeconomic status, education level, living arrangements, health status, pacemakers, physical fitness, and depression. Improving adherence could have a significant impact on longevity, quality of life, and health care costs.
Date: January 22, 2019
Creator: Rivera-Torres, Solymar; Fahey, Thomas D. & Rivera, Miguel A.
System: The UNT Digital Library
Alternative Donor--Acceptor Stacks from Crown Ethers and Naphthalene Diimide Derivatives: Rapid, Selective Formation from Solution and Solid State Grinding (open access)

Alternative Donor--Acceptor Stacks from Crown Ethers and Naphthalene Diimide Derivatives: Rapid, Selective Formation from Solution and Solid State Grinding

Self assembling {pi}-conjugated molecules into ordered structures are of increasing interest in the field of organic electronics. One particular example is charge transfer complexes containing columnar alternative donor-acceptor (ADA) stacks, where neutral and ionic ground states can be readily tuned to modulate electrical, optical, and ferroelectrical properties. Aromatic-aromatic and charge transfer interactions have been the leading driving forces in assisting the self-assembly of ADA stacks. Various folding structures containing ADA stacks were assembled in solution with the aid of solvophobic or ion-binding interactions. Meanwhile, examples of solid ADA stacks, which are more appealing for practical use in devices, were obtained from cocrystalization of binary components or mesophase assembly of liquid crystals in bulk blends. Regardless of these examples, faster and more controllable approaches towards precise supramolecular order in the solid state are still highly desirable.
Date: January 22, 2009
Creator: Lawrence Berkeley National Laboratory. Advanced Light Source.
System: The UNT Digital Library
ANALYSIS OF RECHARGE COOLDOWN AT THE WESTERN BOUNDARY OF CERRO PRIETO I GEOTHERMAL FIELD (open access)

ANALYSIS OF RECHARGE COOLDOWN AT THE WESTERN BOUNDARY OF CERRO PRIETO I GEOTHERMAL FIELD

Extensive study of the Cerro Prieto geothermal field has provided much geologic and thermodynamic data of its structurally-complex, liquid-dominated reservoir. Several of the studies investigated the resource characteristics of fluid and energy flow. An early report by Mercado (1975) showed that the heat source for the part of the reservoir under development, now called Cerro Prieto I (CPI), originated in the eastern part of the field. Subsequent studies confirmed the flow of hot water from the east. A summary of several experimental and numerical studies of fluid and energy transport in the field was given by Lippmann and Bodvarsson (1983). The hydrogeologic model of Halfman et al. (1982) shows hot-water flow from the east divided into a shallow (alpha) aquifer at about 120Om and a deeper (beta) aquifer at about 170Om depth. A cross section along an east-west direction shows a central upflow to the two aquifers and uncertain geology beyond the western border of the field near well M-9. It also shows a fault dividing the line of border wells at M-29 from the inner wells at M-25 to the east. The hydrogeology of the field was described by Sanchez and de la Pena (1981) as an alluvial unit …
Date: January 22, 1985
Creator: Kruger, P.; Lam, S.; Hunsbedt, A.; Esquer, C.; Marquez, R. & Hernandez, L. Cobo, J.
System: The UNT Digital Library
Analytic Model for Richtmyer-Meshkov Turbulent Mixing Widths (open access)

Analytic Model for Richtmyer-Meshkov Turbulent Mixing Widths

None
Date: January 22, 2013
Creator: Mikaelian, K O
System: The UNT Digital Library
Application of Direct Assessment Approaches and Methodologies to Cathodically Protected Nuclear Waste Transfer Lines (open access)

Application of Direct Assessment Approaches and Methodologies to Cathodically Protected Nuclear Waste Transfer Lines

The U.S. Department of Energy's (DOE) Hanford Site is responsible for the safe storage, retrieval, treatment, and disposal of approximately 54 million gallons (204 million liters) of radioactive waste generated since the site's inception in 1943. Today, the major structures involved in waste management at Hanford include 149 carbon steel single-shell tanks, 28 carbon-steel double-shell tanks, plus a network of buried metallic transfer lines and ancillary systems (pits, vaults, catch tanks, etc.) required to store, retrieve, and transfer waste within the tank farm system. Many of the waste management systems at Hanford are still in use today. In response to uncertainties regarding the structural integrity of these systems,' an independent, comprehensive integrity assessment of the Hanford Site piping system was performed. It was found that regulators do not require the cathodically protected pipelines located within the Hanford Site to be assessed by External Corrosion Direct Assessment (ECDA) or any other method used to ensure integrity. However, a case study is presented discussing the application of the direct assessment process on pipelines in such a nuclear environment. Assessment methodology and assessment results are contained herein. An approach is described for the monitoring, integration of outside data, and analysis of this information …
Date: January 22, 2013
Creator: Dahl, Megan M.; Pikas, Joseph; Edgemon, Glenn L. & Philo, Sarah
System: The UNT Digital Library
ASPECTS OF DOE'S CURRENT GEOTHERMAL PROGRAM (open access)

ASPECTS OF DOE'S CURRENT GEOTHERMAL PROGRAM

In bringing you up to date on DOE's geothermal R and D programs, they are going to emphasize first those elements that may be of special interest to a reservoir engineering audience, because the activities in support of an improved understanding of hydrothermal reservoirs deserve attention. Reservoir definition, brine injection, and reservoir stimulation technologies are major elements of the Hydrothermal Research Program, and in total they account for nearly 50% of the fiscal year (FY) 1985 hydrothermal research budget. These elements fall into the essential R and D category; that is, while some basic technologies have been borrowed from the petroleum industry for geothermal service, they are often ill-suited to geothermal requirements, and cannot be used without significant technological innovations. Into this category fall the current reservoir technology, brine injection, and reservoir stimulation projects that are listed in Table 1. The reservoir technology projects include: (1) development of methods for characterizing and mapping reservoir parameters, processes, and spatial dimensions; (2) development of methods to predict and monitor reservoir changes from fluid extraction; (3) evaluation of existing methods and development of new methods for predicting the location and mapping faults and fractures in geothermal reservoirs; and (4) testing of new analysis …
Date: January 22, 1985
Creator: Mock, J. E. & Marshall, J. R.
System: The UNT Digital Library
c-axis twist Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} josephson junctions : a new phase-sensitive test of order parameter symmetry. (open access)

c-axis twist Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} josephson junctions : a new phase-sensitive test of order parameter symmetry.

Li et al. found that the critical current density J{sub c}{sup J} across atomically clean c-axis twist junctions of Bi{sub 2}Sr{sub 2}Ca Cu{sub 2}O{sub 8+{delta}} is the same as that of the constituent single crystal, J{sub c}{sup S}, independent of the twist angle {phi}{sub 0}, even at T{sub c}. They investigated theoretically if a d{sub x{sup 2}-y{sup 2}}-wave order parameter might twist by mixing in d{sub xy} components, but find that such twisting cannot possibly explain the data near to T{sub c}. Hence, the order parameter contains an s-wave component, but not any d{sub x{sup 2}-y{sup 2}}-wave component. In addition, the c-axis Josephson tunneling is completely incoherent. They also propose a c-axis junction tricrystal experiment which does not rely upon expensive substrates.
Date: January 22, 1999
Creator: Klemm, R. A.; Rieck, C. T. & Scharnberg, K.
System: The UNT Digital Library
CALIBRATION OF THE HB LINE ACTIVE WELL NEUTRON COINCIDENCE COUNTER FOR MEASUREMENT OF LANL 3013 HIGHLY ENRICHED URANIUM PRODUCT SPLITS (open access)

CALIBRATION OF THE HB LINE ACTIVE WELL NEUTRON COINCIDENCE COUNTER FOR MEASUREMENT OF LANL 3013 HIGHLY ENRICHED URANIUM PRODUCT SPLITS

In this paper we describe set-up, calibration, and testing of the F-Area Analytical Labs active well neutron coincidence counter(HV-221000-NDA-X-1-DK-AWCC-1)in SRNL for use in HB-Line to enable assay of 3013EU/Pu metal product. The instrument was required within a three-month window for availability upon receipt of LANL Category IV uranium oxide samples into the SRS HB-Line facility. We describe calibration of the instrument in the SRNL nuclear nondestructive assay facility in the range 10-400 g HEU for qualification and installation in HB-Line for assay of the initial suite of product samples.
Date: January 22, 2008
Creator: Dewberry, R; Donald02 Williams, D; Rstephen Lee, R; David-W Roberts, D & Leah Arrigo, L
System: The UNT Digital Library
Cascading effects of COVID-19 on population mobility and air quality: An exploration including place characteristics using geovisualization (open access)

Cascading effects of COVID-19 on population mobility and air quality: An exploration including place characteristics using geovisualization

Article examining the population mobility and air quality before and after the lockdown (mandated restriction of activity) during the public health response to COVID-19. This article is part of the Special Issue on COVID-19.
Date: January 22, 2022
Creator: Atkinson, Samuel F.; Kala, Abhishek K. & Tiwari, Chetan
System: The UNT Digital Library
Comparison of de-noising techniques for FIRST images (open access)

Comparison of de-noising techniques for FIRST images

Data obtained through scientific observations are often contaminated by noise and artifacts from various sources. As a result, a first step in mining these data is to isolate the signal of interest by minimizing the effects of the contaminations. Once the data has been cleaned or de-noised, data mining can proceed as usual. In this paper, we describe our work in denoising astronomical images from the Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) survey. We are mining this survey to detect radio-emitting galaxies with a bent-double morphology. This task is made difficult by the noise in the images caused by the processing of the sensor data. We compare three different approaches to de-noising: thresholding of wavelet coefficients advocated in the statistical community, traditional Altering methods used in the image processing community, and a simple thresholding scheme proposed by FIRST astronomers. While each approach has its merits and pitfalls, we found that for our purpose, the simple thresholding scheme worked relatively well for the FIRST dataset.
Date: January 22, 2001
Creator: Fodor, I K & Kamath, C
System: The UNT Digital Library
Comparison of neutron lifetimes as predicted by MCNP and DANTSYS (open access)

Comparison of neutron lifetimes as predicted by MCNP and DANTSYS

The prompt removal lifetime algorithm used in the latest version of MCNP was modified to conform with the neutron-balance definitions described by Spriggs et al. In accordance with the neutron-balance theory, the non-adjoint-weighted removal lifetime is given by where {Phi} is the angular neutron flux, v is the neutron velocity, {Sigma}{sub a} is the macroscopic absorption cross section, E is neutron energy, {Omega} is angle, and r is a spatial vector. The numerator in this expression represents the total neutron population in the system, N, and the denominator represents the total loss rate due to leakage and absorption.
Date: January 22, 1997
Creator: Hendricks, J.S.; Parsons, D.K. & Spriggs, G.D.
System: The UNT Digital Library
A computational study of the enthalpies of formation of halomethylidynes (open access)

A computational study of the enthalpies of formation of halomethylidynes

Article on a computational study of the enthalpies of formation of halomethylidynes.
Date: January 22, 1999
Creator: Marshall, Paul; Misra, Ashutosh & Schwartz, Martin
System: The UNT Digital Library
Concurrent Multiscale Simulation at Finite Temperature: Coarse-Grained Molecular Dynamics (open access)

Concurrent Multiscale Simulation at Finite Temperature: Coarse-Grained Molecular Dynamics

With the advent of nanotechnology, predictive simulations of nanoscale systems have become in great demand. In some cases nanoscale systems can be simulated directly at the level of atoms. The atomistic techniques used range from models based on a quantum mechanical treatment of the electronic bonds to those based on more empirical descriptions of the interatomic forces. In many cases, however, even nanoscale systems are too big for a purely atomistic approach, typically because the nanoscale device is coupled to its surroundings, and it is necessary to simulate the entire system comprising billions of atoms. A well-known example is the growth of nanoscale epitaxial quantum dots in which the size, shape and location of the dot is affected by the elastic strain developed in a large volume of the substrate as well as the local atomic bonding. The natural solution is to model the surroundings with a more coarse-grained description, suitable for the intrinsically longer length scale. The challenge then is to develop the computational methodology suitable for this kind of concurrent multiscale modeling, one in which the simulated length scale can be changed smoothly and seamlessly from one region of the simulation to another while maintaining the fidelity of …
Date: January 22, 2004
Creator: Rudd, R E
System: The UNT Digital Library
CORRELATIONS BETWEEN VAPOR SATURATION, FLUID COMPOSITION, AND WELL DECLINE IN LARDERELLO (open access)

CORRELATIONS BETWEEN VAPOR SATURATION, FLUID COMPOSITION, AND WELL DECLINE IN LARDERELLO

A large body of field data from Larderello shows striking temporal correlations between decline of well flow-rate, produced gas/steam ratio, chloride concentration and produced vapor fraction. The latter is inferred from measured concentrations of non-condensible gases in samples of well fluid, using chemical phase equilibrium principles. Observed temporal changes in the vapor fractions can be interpreted in term of a ''multiple source'' model, as suggested by D'Amore and Truesdell (1979). This provides clues to the dynamics of reservoir depletion, and to the evaluation of well productivity and longevity.
Date: January 22, 1985
Creator: D'Amore, F. & Pruess, K.
System: The UNT Digital Library
Cosmic-ray Propagation and Interactions in the Galaxy (open access)

Cosmic-ray Propagation and Interactions in the Galaxy

We survey the theory and experimental tests for the propagation of cosmic rays in the Galaxy up to energies of 10{sup 15} eV. A guide to the previous reviews and essential literature is given, followed by an exposition of basic principles. The basic ideas of cosmic-ray propagation are described, and the physical origin of its processes are explained. The various techniques for computing the observational consequences of the theory are described and contrasted. These include analytical and numerical techniques. We present the comparison of models with data including direct and indirect--especially gamma-ray--observations, and indicate what we can learn about cosmic-ray propagation. Some particular important topics including electrons and antiparticles are chosen for discussion.
Date: January 22, 2007
Creator: Strong, Andrew W.; /Garching, Max Planck Inst., MPE; Moskalenko, Igor V.; /Stanford U., HEPL /KIPAC, Menlo Park; Ptuskin, Vladimir S. & /Troitsk, IZMIRAN
System: The UNT Digital Library
Crystallization of a member of the recFOR DNA repair pathway, RecO, with and without bound oligonucleotide (open access)

Crystallization of a member of the recFOR DNA repair pathway, RecO, with and without bound oligonucleotide

RecFOR proteins are important for DNA repair by homologous recombination in bacteria. The RecO protein from Thermus thermophilus was cloned, purified and characterized for its binding to oligonucleotides. The protein was crystallized alone and in complex with a 14-mer oligonucleotide. Both crystal forms grow under different crystallization conditions in the same space group, P3121 or P3221, with almost identical unit cell parameters. Complete data sets were collected to 2.8 Angstrom and 2.5 Angstrom for RecO alone and the RecO-oligonucleotide complex, respectively. Visual comparison of the diffraction patterns between the two crystal forms and calculation of an Rmerge of 33.9 percent on F indicate that one of the crystal forms is indeed a complex of RecO with bound oligonucleotide.
Date: January 22, 2003
Creator: Aono, Shelly; Hartsch, Thomas & Schulze-Gahmen, Ursula
System: The UNT Digital Library
Crystallographically degenerate B2 precipitation in a plastically deformed fcc-based complex concentrated alloy (open access)

Crystallographically degenerate B2 precipitation in a plastically deformed fcc-based complex concentrated alloy

Article describes the development of bcc-ordered B2 and fcc phases manifested in three different orientation relationships (ORs) in the same microstructure: Kurdjumov–Sachs, Nishiyama–Wasserman and Pitsch.
Date: January 22, 2018
Creator: Choudhuri, Deep; Shukla, Shivakant; Green, Whitley; Gwalani, Bharat; Ageh, Victor; Banerjee, Rajarshi et al.
System: The UNT Digital Library
Decline Curve Analysis for Infinite Double-Porosity Systems Without Wellbore Skin (open access)

Decline Curve Analysis for Infinite Double-Porosity Systems Without Wellbore Skin

This paper presents a transient pressure analysis method for analyzing the rate decline of a constant pressure well producing in an infinite double-porosity reservoir, without wellbore skin. This analysis method may be used to interpret well test rate data, and to compute the rate behavior of an infinitely acting reservoir that is being produced at constant pressure. The development of the pseudo steady state log-log type curve Is presented along with a hypothetical example of its use. This type curve allows the estimation of the two controlling parameters in double-porosity systems: {lambda} and {omega}. The first parameter, {lambda}, describes the interporosity flow, and the second parameter, {omega} describes the relative fracture storativity. This paper considers the estimation of these two parameters. The estimations of permeabilities and storativities have been described in the past, hence, are not considered. In a double-porosity system, with pseudo steady state interporosity flow, the initial infinite acting rate decline, representing only the fracture system, is followed by a constant rate flow period. The length of this constant rate flow period is controlled by the parameter {omega}. The beginning of this period is controlled by the interporosity flow parameter, {lambda}. Following this constant rate period, the rate …
Date: January 22, 1985
Creator: Sageev, A.; Da Prat, G. & Ramey, H. J., Jr.
System: The UNT Digital Library
DEEP VADOSE ZONE CONTAMINATION DUE TO RELEASES FROM HANFORD SITE TANKS (open access)

DEEP VADOSE ZONE CONTAMINATION DUE TO RELEASES FROM HANFORD SITE TANKS

CH2M HILL Hanford Group, Inc. (the Hanford Tank Farm Operations contractor) and the Department of Energy's Office of River Protection have just completed the first phase of the Hanford Single-Shell Tank RCRA Corrective Action Program. The focus of this first phase was to characterize the nature and extent of past Hanford single-shell tank releases and to characterize the resulting fate and transport of the released contaminants. Most of these plumes are below 20 meters, with some reaching groundwater (at 60 to 120 meters below ground surface [bgs]).
Date: January 22, 2008
Creator: MN, JARAYSI
System: The UNT Digital Library
Detailed Chemical Kinetic Reaction Mechanism for Biodiesel Components Methyl Stearate and Methyl Oleate (open access)

Detailed Chemical Kinetic Reaction Mechanism for Biodiesel Components Methyl Stearate and Methyl Oleate

New chemical kinetic reaction mechanisms are developed for two of the five major components of biodiesel fuel, methyl stearate and methyl oleate. The mechanisms are produced using existing reaction classes and rules for reaction rates, with additional reaction classes to describe other reactions unique to methyl ester species. Mechanism capabilities were examined by computing fuel/air autoignition delay times and comparing the results with more conventional hydrocarbon fuels for which experimental results are available. Additional comparisons were carried out with measured results taken from jet-stirred reactor experiments for rapeseed methyl ester fuels. In both sets of computational tests, methyl oleate was found to be slightly less reactive than methyl stearate, and an explanation of this observation is made showing that the double bond in methyl oleate inhibits certain low temperature chain branching reaction pathways important in methyl stearate. The resulting detailed chemical kinetic reaction mechanism includes more approximately 3500 chemical species and more than 17,000 chemical reactions.
Date: January 22, 2010
Creator: Naik, C; Westbrook, C K; Herbinet, O; Pitz, W J & Mehl, M
System: The UNT Digital Library
Development of a Novel Depleted Uranium Treatment Process at Lawrence Livermore National Laboratory (open access)

Development of a Novel Depleted Uranium Treatment Process at Lawrence Livermore National Laboratory

A three-stage process was developed at Lawrence Livermore National Laboratory to treat potentially pyrophoric depleted uranium metal wastes. The three-stage process includes waste sorting/rinsing, acid dissolution of the waste metal with a hydrochloric and phosphoric acid solution, and solidification of the neutralized residuals from the second stage with clay. The final product is a solid waste form that can be transported to and disposed of at a permitted low-level radioactive waste disposal site.
Date: January 22, 2007
Creator: Gates-Anderson, D.; Bowers, J.; Laue, C. & Fitch, T.
System: The UNT Digital Library