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The 0.38 Percent Across-the-Board Cut in FY2000 Appropriations

Description: This report outlines cuts made in the federal budget for FY2000. The 0.38% cut was expected to yield savings of $2.4 billion in budget authority and $1.4 billion in outlays for the fiscal year. Departments with cuts in excess of $100 million included the Departments of Defense, Transportation, Health and Human Services, and Education.
Date: February 25, 2000
Creator: Keith, Robert
Partner: UNT Libraries Government Documents Department

1/6TH SCALE STRIP EFFLUENT FEED TANK-MIXING RESULTS USING MCU SOLVENT

Description: The purpose of this task was to determine if mixing was an issue for the entrainment and dispersion of the Modular Caustic Side Solvent Extraction (CSSX) Unit (MCU) solvent in the Defense Waste Processing Facility (DWPF) Strip Effluent Feed Tank (SEFT). The MCU strip effluent stream containing the Cs removed during salt processing will be transferred to the DWPF for immobilization in HLW glass. In lab-scale DWPF chemical process cell testing, mixing of the solvent in the dilute nitric acid solution proved problematic, and the Savannah River National Laboratory (SRNL) was requested to perform scaled SEFT mixing tests to evaluate whether the problem was symptomatic of the lab-scale set-up or of the solvent. The solvent levels tested were 228 and 235 ppm, which represented levels near the estimated DWPF solvent limit of 239 ppm in 0.001M HNO{sub 3} solution. The 239 ppm limit was calculated by Norato in X-CLC-S-00141. The general approach for the mixing investigation was to: (1) Investigate the use of fluorescent dyes to aid in observing the mixing behavior. Evaluate and compare the physical properties of the fluorescent dyed MCU solvents to the baseline Oak Ridge CSSX solvent. Based on the data, use the dyed MCU solvent that best approximates the physical properties. (2) Use approximately a 1/6th linear scale of the SEFT to replicate the internal configuration for DWPF mixing. (3) Determine agitator speed(s) for scaled testing based on the DWPF SEFT mixing speed. (4) Perform mixing tests using the 1/6th SEFT and determine any mixing issues (entrainment/dispersion, accumulation, adhesion) through visual observations and by pulling samples to assess uniformity. The mixing tests used MCU solvent fabricated at SRNL blended with Risk Reactor DFSB-K43 fluorescent dye. This dyed SRNL MCU solvent had equivalent physical properties important to mixing as compared to the Oak Ridge baseline solvent, ...
Date: February 1, 2006
Creator: Hansen, E.
Partner: UNT Libraries Government Documents Department

01-ERD-111 - The Development of Synthetic High Affinity Ligands

Description: The aim of this project was to develop Synthetic High-Affinity Ligands (SHALs), which bind with high affinity and specificity to proteins of interest for national security and cancer therapy applications. The aim of producing synthetic ligands for sensory devices as an alternative to antibody-based detection assays and therapeutic agents is to overcome the drawbacks associated with antibody-based in next-generation sensors and systems. The focus area of the project was the chemical synthesis of the SHALs. The project concentrated on two different protein targets. (a) The C fragment of tetanus and botulinum toxin, potential biowarfare agents. A SHAL for tetanus or botulinum toxin would be incorporated into a sensory device for the toxins. (b) HLA-DR10, a protein found in high abundance on the surface of Non-Hodgkins Lymphoma. A SHAL specific to a tumor marker, labeled with a radionuclide, would enable the targeted delivery of radiation therapy to metastatic disease. The technical approach used to develop a SHAL for each protein target will be described in more detail below. However, in general, the development of a SHAL requires a combination of computational modeling techniques, modern nuclear magnetic resonance spectroscopy (NMR) and synthetic chemistry.
Date: February 5, 2004
Creator: Perkins, J; Balhorn, R; Cosman, M; Lightstone, F & Zeller, L
Partner: UNT Libraries Government Documents Department

1/m<sub>c</sub> Terms in lambda<sup>+</sup><sub>c</sub> Semileptonic Decays

Description: We use the heavy quark effective theory to investigate the form factors that describe the semileptonic decays lambda<sup>+</sup><sub>c</sub> -> lambda e<sup>+</sup> nu, to order 1/m<sub>c</sub>. We find that a total of four form factors are needed to this order, in contrast with two form factors to leading order, and six form factors in the most general case. We point out some relationships that arise among the general form factors.
Date: February 1, 1992
Creator: Roberts, Winston
Partner: UNT Libraries Government Documents Department

1 to 2 GeV/c beam line for hypernuclear and kaon research

Description: A kaon beam line operating in the range from 1.0 to 2.0 GeV/c is proposed. The line is meant for kaon and pion research in a region hitherto inaccessible to experimenters. Topics in hypernuclear and kaon physics of high current interest include the investigation of doubly strange nuclear systems with the K/sup -/,K/sup +/ reaction, searching for dibaryon resonances, hyperon-nucleon interactions, hypernuclear ..gamma.. rays, and associated production of excited hypernuclei. The beam line would provide separated beams of momentum analyzed kaons at intensities greater than 10/sup 6/ particles per spill with a momentum determined to one part in a thousand. This intensity is an order of magnitude greater than that currently available. 63 references.
Date: February 15, 1985
Creator: Chrien, R.E.
Partner: UNT Libraries Government Documents Department

1-watt composite-slab Er:YAG laser. Revision 1

Description: A diode-side-pumped discrete-optic Er{sup 3+} :YAG laser employs pump-light coupling through a sapphire plate diffusion-bonded to the laser slab, removing heat directly at the pump face of the slab instead of requiring conduction through to its far side. This lowers the temperature in the gain region and gives reduced thermal lensing, which produces exceptional beam quality (M{sup 2} {approx} 1.3) at output powers {approx} 0.3 Watt. Powers above 1 Watt have been demonstrated with peak slope efficiencies {approx}20%. The novel architecture is also applicable to other side-pumped lasers.
Date: February 13, 1997
Creator: Page, R. H.; Bartels, R. A.; Beach, R. J.; Sutton, S. B.; Furu, L. H. & LaSala, J. E.
Partner: UNT Libraries Government Documents Department

The 2.3 {angstrom} crystal structure of cholera toxin B subunit pentamer: Choleragenoid

Description: Cholera toxin, a heterohexameric AB{sub 5} enterotoxin released by Vibrio cholera, induces a profuse secretory diarrhea in susceptible hosts. Choleragenoid, the B subunit pentamer of cholera toxin, directs the enzymatic A subunit to its target by binding to GM{sub 1} gangliosides exposed on the luminal surface of intestinal epithelial cells. We have solved the crystal structure of choleragenoid at 2.3 {Angstrom} resolution by combining single isomorphous replacement with non-crystallographic symmetry averaging. The structure of the B subunits, and their pentameric arrangement, closely resembles that reported for the intact holotoxin (choleragen), the heat-labile enterotoxin from E. coli, and for a choleragenoid-GM{sub 1} pentasaccharide complex. In the absence of the A subunit the central cavity of the B pentamer is a highly solvated channel. The binding of the A subunit or the receptor pentasaccharide to choleragenoid has only a modest effect on the local stereochemistry and does not perceptibly alter the subunit interface.
Date: February 1, 1996
Creator: Zhang, Rong-Guang; Westbrook, M.L.; Maulik, P.R.; Reed, R.A.; Shipley, G.; Westbrook, E.M. et al.
Partner: UNT Libraries Government Documents Department

3-body final states in peripheral heavy-ion collisions: nuclear clustering structure and projectile excitation revisited

Description: Even though peripheral heavy-ion collisions are less violent than their central counterparts, the large energy exchange between the reactants often leaves the primary products in excited particle-unstable states whose subsequent decay leads to 3 or more nuclei emerging in the final exit channel. These post-reaction, predominantly sequential de-excitation processes can sometimes provide interesting structural information about the parent nuclei. In fact, provided these processes are well understood, one can employ them as probes for studying initial properties of the fragments. This report discusses results of two experiments that deal with (1) nonstatistical, rare decay modes of the projectile, and (2) internal excitation energy of the projectile- and target-like fragments in peripheral collisions. The physics addressed in each is different, but the experimental and data-analysis techniques are so similar that it is relevant to join them together.
Date: February 1, 1986
Creator: Chan, Y.; Chavez, E.; Gazes, S.B.; Kamermans, R.; Schmidt, H.R.; Siwek-Wilczynska, J. et al.
Partner: UNT Libraries Government Documents Department

3-D Finite Element Analyses of the Egan Cavern Field

Description: Three-dimensional finite element analyses were performed for the two gas-filled storage caverns at the Egan field, Jennings dome, Louisiana. The effects of cavern enlargement on surface subsidence, storage loss, and cavern stability were investigated. The finite element model simulated the leaching of caverns to 6 and 8 billion cubic feet (BCF) and examined their performance at various operating conditions. Operating pressures varied from 0.15 psi/ft to 0.9 psi/ft at the bottom of the lowest cemented casing. The analysis also examined the stability of the web or pillar of salt between the caverns under differential pressure loadings. The 50-year simulations were performed using JAC3D, a three dimensional finite element analysis code for nonlinear quasistatic solids. A damage criterion based on onset of dilatancy was used to evaluate cavern instability. Dilation results from the development of microfractures in salt and, hence, potential increases in permeability onset occurs well before large scale failure. The analyses predicted stable caverns throughout the 50-year period for the range of pressures investigated. Some localized salt damage was predicted near the bottom walls of the caverns if the caverns are operated at minimum pressure for long periods of time. Volumetric cavern closures over time due to creep were moderate to excessive depending on the salt creep properties and operating pressures. However, subsidence above the cavern field was small and should pose no problem, to surface facilities.
Date: February 1, 1999
Creator: Klamerus, E.W. & Ehgartner, B.L.
Partner: UNT Libraries Government Documents Department

3-D Force-balanced Magnetospheric Configurations

Description: The knowledge of plasma pressure is essential for many physics applications in the magnetosphere, such as computing magnetospheric currents and deriving magnetosphere-ionosphere coupling. A thorough knowledge of the 3-D pressure distribution has however eluded the community, as most in-situ pressure observations are either in the ionosphere or the equatorial region of the magnetosphere. With the assumption of pressure isotropy there have been attempts to obtain the pressure at different locations by either (a) mapping observed data (e.g., in the ionosphere) along the field lines of an empirical magnetospheric field model or (b) computing a pressure profile in the equatorial plane (in 2-D) or along the Sun-Earth axis (in 1-D) that is in force balance with the magnetic stresses of an empirical model. However, the pressure distributions obtained through these methods are not in force balance with the empirical magnetic field at all locations. In order to find a global 3-D plasma pressure distribution in force balance with the magnetospheric magnetic field, we have developed the MAG-3D code, that solves the 3-D force balance equation J x B = (upside-down delta) P computationally. Our calculation is performed in a flux coordinate system in which the magnetic field is expressed in terms of Euler potentials as B = (upside-down delta) psi x (upside-down delta) alpha. The pressure distribution, P = P(psi,alpha), is prescribed in the equatorial plane and is based on satellite measurements. In addition, computational boundary conditions for y surfaces are imposed using empirical field models. Our results provide 3-D distributions of magnetic field and plasma pressure as well as parallel and transverse currents for both quiet-time and disturbed magnetospheric conditions.
Date: February 10, 2003
Creator: Zaharia, Sorin; Cheng, C. Z. & Maezawa, K.
Partner: UNT Libraries Government Documents Department

A 3-d modular gripper design tool

Description: Modular fixturing kits are sets of components used for flexible, rapid construction of fixtures. A modular vise is a parallel-jaw vise, each jaw of which is a modular fixture plate with a regular grid of precisely positioned holes. To fixture a part, one places pins in some of the holes so that when the vise is closed, the part is reliably located and completely constrained. The modular vise concept can be adapted easily to the design of modular parallel-jaw grippers for robots. By attaching a grid-plate to each jaw of a parallel-jaw gripper, one gains the ability to easily construct high-quality grasps for a wide variety of parts from a standard set of hardware. Wallack and Canny developed an algorithm for planning planar grasp configurations for the modular vise. In this paper, the authors expand this work to produce a 3-d fixture/gripper design tool. They describe several analyses they have added to the planar algorithm, including a 3-d grasp quality metric based on force information, 3-d geometric loading analysis, and inter-gripper interference analysis. Finally, the authors describe two applications of their code. One of these is an internal application at Sandia, while the other shows a potential use of the code for designing part of an agile assembly line.
Date: February 1, 1997
Creator: Brown, R.G. & Brost, R.C.
Partner: UNT Libraries Government Documents Department

3-D Numerical Modeling of a Complex Salt Structure

Description: Reliably processing, imaging, and interpreting seismic data from areas with complicated structures, such as sub-salt, requires a thorough understanding of elastic as well as acoustic wave propagation. Elastic numerical modeling is an essential tool to develop that understanding. While 2-D elastic modeling is in common use, 3-D elastic modeling has been too computationally intensive to be used routinely. Recent advances in computing hardware, including commodity-based hardware, have substantially reduced computing costs. These advances are making 3-D elastic numerical modeling more feasible. A series of example 3-D elastic calculations were performed using a complicated structure, the SEG/EAGE salt structure. The synthetic traces show that the effects of shear wave propagation can be important for imaging and interpretation of images, and also for AVO and other applications that rely on trace amplitudes. Additional calculations are needed to better identify and understand the complex wave propagation effects produced in complicated structures, such as the SEG/EAGE salt structure.
Date: February 17, 2000
Creator: House, L.; Larsen, S. & Bednar, J. B.
Partner: UNT Libraries Government Documents Department

3-D sedimentological and geophysical studies of clastic reservoir analogs: Facies architecture, reservoir properties, and flow behavior within delta front facies elements of the Cretaceous Wall Creek Member, Frontier Formation, Wyoming

Description: This project examined the internal architecture of delta front sandstones at two locations within the Turonian-age Wall Creek Member of the Frontier Formation, in Wyoming. The project involved traditional outcrop field work integrated with core-data, and 2D and 3D ground penetrating radar (GPR) imaging from behind the outcrops. The fluid-flow engineering work, handled through a collaborative grant given to PI Chris White at LSU, focused on effects on fluid flow of late-stage calcite cement nodules in 3D. In addition to the extensive field component, the work funded 2 PhD students (Gani and Lee) and resulted in publication of 10 technical papers, 17 abstracts, and 4 internal field guides. PI Bhattacharya also funded an additional 3 PhD students that worked on the Wall Creek sandstone funded separately through an industrial consortium, two of whom graduated in the fall 2006 ((Sadeque and Vakarelov). These additional funds provided significant leverage to expand the work to include a regional stratigraphic synthesis of the Wall Creek Member of the Frontier Formation, in addition to the reservoir-scale studies that DOE directly funded. Awards given to PI Bhattacharya included the prestigious AAPG Distinguished Lecture Award, which involved a tour of about 25 Universities and Geological Societies in the US and Canada in the fall of 2005 and Spring of 2006. Bhattacharya gave two talks, one entitled “Applying Deltaic and Shallow Marine Outcrop Analogs to the Subsurface”, which highlighted the DOE sponsored work and the other titled “Martian River Deltas and the Origin of Life”. The outcrop analog talk was given at about 1/2 of the venues visited.
Date: February 16, 2007
Creator: Bhattacharya, Janok P. & McMechan, George A.
Partner: UNT Libraries Government Documents Department

3-D Seismic Imaging of Complex Geologies

Description: We present three codes for the Intel Paragon that address the problem of three-dimensional seismic imaging of complex geologies. The first code models acoustic wave propagation and can be used to generate data sets to calibrate and validate seismic imaging codes. This code reported the fastest timings for acoustic wave propagation codes at a recent SEG (Society of Exploration Geophysicists) meeting. The second code implements a Kirchhoff method for pre-stack depth migration. Development of this code is almost complete, and preliminary results are presented. The third code implements a wave equation approach to seismic migration and is a Paragon implementation of a code from the ARCO Seismic Benchmark Suite.
Date: February 1, 1995
Creator: Womble, David E.; Dosanjh, Sudip S.; VanDyke, John P.; Oldfield, Ron A. & Greenberg, David S.
Partner: UNT Libraries Government Documents Department

3-D slug flow heat transfer analysis of coupled coolant cells in finite LMFBR bundles

Description: A three-dimensional single region slug flow heat transfer analysis for finite LMFBR rod bundles using a classical analytical solution method has been performed. According to the isolated single cell analysis, the results show that the peripheral clad temperature variation as well as the thermal entrance length are strongly dependent upon the degree of irregularity displayed by various coolant geometries. Since under the present LMFBR conditions, fully-developed temperature fields may hardly be established in such characteristic rod bundle regions, a 3-D heat transfer analysis seems to be mandatory. This implies that the results of fully developed heat transfer analyses are by far too conservative.
Date: February 1, 1978
Creator: Wong, C.N. & Wolf, L.
Partner: UNT Libraries Government Documents Department

A 3-dimensional ray-trace model for predicting the performance of flashlamp-pumped laser amplifiers

Description: We have developed a fully three-dimensional model for the performance of flashlamp pumped laser amplifiers. The model uses a reverse ray-trace technique to calculate the pumping of the laser glass by the flashlamp radiation. We have discovered several different methods by which we can speed up the calculation of the gain profile in a amplifier. The model predicts the energy-storage performance of the Beamlet amplifiers to better than 5%. This model will be used in the optimization of the National Ignition Facility (NIF) amplifier design.
Date: February 13, 1997
Creator: Jancaitis, K.S.; Haney, S.W.; Munro, D.H.; Le Touze, G. & Cabourdin, O.
Partner: UNT Libraries Government Documents Department

T-3 electron-beam-excited laser system

Description: A laser system specifically designed to study the kinetics of electron-beam driven systems is described. Details of the system are given along with measurements of the electron-beam uniformity and deposition in the laser medium. Some HF laser results obtained with this system are also given.
Date: February 1, 1981
Creator: Klein, R. A.
Partner: UNT Libraries Government Documents Department

3(omega) Damage: Growth Mitigation

Description: The design of high power UV laser systems is limited to a large extent by the laser-initiated damage performance of transmissive fused silica optical components. The 3{omega} (i.e., the third harmonic of the primary laser frequency) damage growth mitigation LDRD effort focused on understanding and reducing the rapid growth of laser-initiated surface damage on fused silica optics. Laser-initiated damage can be discussed in terms of two key issues: damage initiated at some type of precursor and rapid damage growth of the damage due to subsequent laser pulses. The objective of the LDRD effort has been the elucidation of laser-induced damage processes in order to quantify and potentially reduce the risk of damage to fused silica surfaces. The emphasis of the first two years of this effort was the characterization and reduction of damage initiation. In spite of significant reductions in the density of damage sites on polished surfaces, statistically some amount of damage initiation should always be expected. The early effort therefore emphasized the development of testing techniques that quantified the statistical nature of damage initiation on optical surfaces. This work led to the development of an optics lifetime modeling strategy that has been adopted by the NIF project to address damage-risk issues. During FY99 interest shifted to the damage growth issue which was the focus of the final year of this project. The impact of the remaining damage sites on laser performance can be minimized if the damage sites did not continue to grow following subsequent illumination. The objectives of the final year of the LDRD effort were to apply a suite of state-of-the-art characterization tools to elucidate the nature of the initiated damage sites, and to identify a method that effectively mitigates further damage growth. Our specific goal is to understand the cause for the rapid growth of ...
Date: February 22, 2001
Creator: Kozlowski, M; Demos, S; Wu, Z-L; Wong, J; Penetrante, B & Hrubesh, L
Partner: UNT Libraries Government Documents Department

04-ERD-052-Final Report

Description: Generating the sequence of the human genome represents a colossal achievement for science and mankind. The technical use for the human genome project information holds great promise to cure disease, prevent bioterror threats, as well as to learn about human origins. Yet converting the sequence data into biological meaningful information has not been immediately obvious, and we are still in the preliminary stages of understanding how the genome is organized, what are the functional building blocks and how do these sequences mediate complex biological processes. The overarching goal of this program was to develop novel methods and high throughput strategies for determining the functions of ''anonymous'' human genes that are evolutionarily deeply conserved in other vertebrates. We coupled analytical tool development and computational predictions regarding gene function with novel high throughput experimental strategies and tested biological predictions in the laboratory. The tools required for comparative genomic data-mining are fundamentally the same whether they are applied to scientific studies of related microbes or the search for functions of novel human genes. For this reason the tools, conceptual framework and the coupled informatics-experimental biology paradigm we developed in this LDRD has many potential scientific applications relevant to LLNL multidisciplinary research in bio-defense, bioengineering, bionanosciences and microbial and environmental genomics.
Date: February 26, 2007
Creator: Loots, G G; Ovcharenko, I; Collette, N; Babu, P; Chang, J; Stubbs, L et al.
Partner: UNT Libraries Government Documents Department

4 K to 20 K rotational-cooling magnetic refrigerator capable of 1-mW to >1-W operation

Description: The low-temperature, magnetic entropy of certain single-crystal paramagnetic materials, such as DyPO/sub 4/, changes dramatically as the crystal rotates in a magnetic field. A new magnetic refrigerator design based on the anisotropic nature of such materials is presented. The key advantages of the rotational-cooling concept are (1) a single, rotary motion is required, (2) magnetic field shaping is not a problem because the entire working material is in a constant field, and (3) the refrigerator can be smaller than comparable magnetic refrigerators because the working material is entirely inside the magnet at all times. The main disadvantage of the rotational-cooling concept is that small-dimension single crystals are required.
Date: February 1, 1980
Creator: Barclay, J.A.
Partner: UNT Libraries Government Documents Department

N >= 4 Supergravity Amplitudes from Gauge Theory at Two Loops

Description: We present the full two-loop four-graviton amplitudes in N = 4, 5, 6 supergravity. These results were obtained using the double-copy structure of gravity, which follows from the recently conjectured color-kinematics duality in gauge theory. The two-loop four-gluon scattering amplitudes in N = 0, 1, 2 supersymmetric gauge theory are a second essential ingredient. The gravity amplitudes have the expected infrared behavior: the two-loop divergences are given in terms of the squares of the corresponding one-loop amplitudes. The finite remainders are presented in a compact form. The finite remainder for N = 8 supergravity is also presented, in a form that utilizes a pure function with a very simple symbol.
Date: February 15, 2012
Creator: Boucher-Veronneau, C. & Dixon, L. J.
Partner: UNT Libraries Government Documents Department