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Lessons from Two Years of Building Fusion Ignition Targets with the Precision Robotic Assembly Machine (open access)

Lessons from Two Years of Building Fusion Ignition Targets with the Precision Robotic Assembly Machine

The Precision Robotic Assembly Machine was developed to manufacture the small and intricate laser-driven fusion ignition targets that are being used in the world's largest and most energetic laser, the National Ignition Facility (NIF). The National Ignition Campaign (NIC) goal of using the NIF to produce a self-sustaining nuclear fusion burn with energy gain - for the first time ever in a laboratory setting - requires targets that are demanding in materials fabrication, machining, and assembly. We provide an overview of the design and function of the machine, with emphasis on the aspects that revolutionized how NIC targets are manufactured.
Date: February 19, 2010
Creator: Montesanti, R C; Alger, E T; Atherton, L J; Bhandarkar, S D; Castro, C; Dzenitis, E G et al.
Object Type: Article
System: The UNT Digital Library
Transport Properties for Combustion Modeling (open access)

Transport Properties for Combustion Modeling

This review examines current approximations and approaches that underlie the evaluation of transport properties for combustion modeling applications. Discussed in the review are: the intermolecular potential and its descriptive molecular parameters; various approaches to evaluating collision integrals; supporting data required for the evaluation of transport properties; commonly used computer programs for predicting transport properties; the quality of experimental measurements and their importance for validating or rejecting approximations to property estimation; the interpretation of corresponding states; combination rules that yield pair molecular potential parameters for unlike species from like species parameters; and mixture approximations. The insensitivity of transport properties to intermolecular forces is noted, especially the non-uniqueness of the supporting potential parameters. Viscosity experiments of pure substances and binary mixtures measured post 1970 are used to evaluate a number of approximations; the intermediate temperature range 1 < T* < 10, where T* is kT/{var_epsilon}, is emphasized since this is where rich data sets are available. When suitable potential parameters are used, errors in transport property predictions for pure substances and binary mixtures are less than 5 %, when they are calculated using the approaches of Kee et al.; Mason, Kestin, and Uribe; Paul and Warnatz; or Ern and Giovangigli. Recommendations stemming …
Date: February 19, 2010
Creator: Brown, N. J.; Bastein, L. & Price, P. N.
Object Type: Article
System: The UNT Digital Library
Quantification of thin film crystallographic orientation using X-ray diffraction with an area detector (open access)

Quantification of thin film crystallographic orientation using X-ray diffraction with an area detector

As thin films become increasingly popular (for solar cells, LEDs, microelectronics, batteries), quantitative morphological information is needed to predict and optimize the film's electronic, optical and mechanical properties. This quantification can be obtained quickly and easily with X-ray diffraction using an area detector and synchrotron radiation in two simple geometries. In this paper, we describe a methodology for constructing complete pole figures for thin films with fiber texture (isotropic in-plane orientation). We demonstrate this technique on semicrystalline polymer films, self-assembled nanoparticle semiconductor films, and randomly-packed metallic nanoparticle films. This method can be immediately implemented to help understand the relationship between film processing and microstructure, enabling the development of better and less expensive electronic and optoelectronic devices.
Date: February 19, 2010
Creator: Baker, Jessica L; Jimison, Leslie H; Mannsfeld, Stefan; Volkman, Steven; Yin, Shong; Subramanian, Vivek et al.
Object Type: Article
System: The UNT Digital Library
Evaluate trade-offs between I/sub sp/ and lifetime for a specified fuel elements state-of-the-art (open access)

Evaluate trade-offs between I/sub sp/ and lifetime for a specified fuel elements state-of-the-art

None
Date: February 19, 1971
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Core wrapper axial flow impedance tests (open access)

Core wrapper axial flow impedance tests

None
Date: February 19, 1968
Creator: Rostand, L.E.
Object Type: Report
System: The UNT Digital Library
CALCULATION OF WALL-SCATTERED GAMMA RADIATION ESCAPING THROUGH A SHIELD OPENING--APPLICATION TO THE HRT (open access)

CALCULATION OF WALL-SCATTERED GAMMA RADIATION ESCAPING THROUGH A SHIELD OPENING--APPLICATION TO THE HRT

None
Date: February 19, 1957
Creator: Claiborne, H.C. & Fowler, T.B.
Object Type: Report
System: The UNT Digital Library
A PORTABLE BANDSAW FOR HOT CELL USE (open access)

A PORTABLE BANDSAW FOR HOT CELL USE

A commercial light-weight portable bandsaw was fitted with a grip to permit it to be maneuvered remotely in a hot cell by means of a General Mills manipulator The bandsaw was supported in various positions to make cuts on typical pieces. Photographs show the saw in operation. (auth)
Date: February 19, 1958
Creator: Abbatiello, A. A.
Object Type: Report
System: The UNT Digital Library
Preliminary Safety Evaluation of the Sodium Reactor Experiment (open access)

Preliminary Safety Evaluation of the Sodium Reactor Experiment

A description is given of the Sodium Reactor Experiment (SRE) facilities and program of objectives. The hazards associated with equipment failures and malfunctions, personnel errors, natural causes, and operation are evaluated (C.J.G.)
Date: February 19, 1954
Creator: Abott, W. E.
Object Type: Report
System: The UNT Digital Library
Development of a reliable, low-cost, energy-storage capacitor for laser pumping (open access)

Development of a reliable, low-cost, energy-storage capacitor for laser pumping

None
Date: February 19, 1975
Creator: Hutzler, J.R. & Gagnon, W.L.
Object Type: Article
System: The UNT Digital Library
PRELIMINARY FIELD EVALUATION OF MERCURY CONTROL USING COMBUSTION MODIFICATIONS (open access)

PRELIMINARY FIELD EVALUATION OF MERCURY CONTROL USING COMBUSTION MODIFICATIONS

In this project General Electric Energy and Environmental Research Corporation conducts a preliminary field evaluation of a novel technology, referred to as Hg/NO{sub x}, that can reduce emissions of both mercury (Hg) and oxides of nitrogen (NO{sub x}) from coal-fired power plants. The evaluation takes place in Green Station Unit 2 operated by Western Kentucky Energy. Reduction of Hg and NO{sub x} emissions in Unit 2 is achieved using coal reburning. Activities during first project year (January 23, 2003--January 22, 2004) included measurements of baseline Hg emissions in Unit 2 and pilot-scale testing. Baseline testing of Hg emissions in Green Unit 2 has been completed. Two fuels were tested with OFA system operating at minimum air flow. Mercury emissions were measured at ESP inlet and outlet, and at the stack using Ontario Hydro revised method. Testing demonstrated that baseline Hg reductions at ESP outlet and stack were 30-45% and 70-80%, respectively. Pilot-scale testing demonstrated good agreement with baseline measurements in Unit 2. Testing showed that fuel composition had an effect on the efficiency of Hg absorption on fly ash. Maximum achieved Hg removal in reburning was close to 90%. Maximum achieved Hg reduction at air staging conditions was 60%. Testing …
Date: February 19, 2004
Creator: Lissianski, Vitali & Marquez, Antonio
Object Type: Report
System: The UNT Digital Library
Strontium Isotopes in Pore Water as an Indicator of Water Flux at the Proposed High-Level Radioactive Waste Repository, Yucca Mountain, Nevada (open access)

Strontium Isotopes in Pore Water as an Indicator of Water Flux at the Proposed High-Level Radioactive Waste Repository, Yucca Mountain, Nevada

The proposed high-level radioactive waste repository at Yucca Mountain, Nevada, would be constructed in the high-silica rhyolite (Tptp) member of the Miocene-age Topopah Spring Tuff, a mostly welded ash-flow tuff in the {approx}500-m-thick unsaturated zone. Strontium isotope compositions have been measured in pore water centrifuged from preserved core samples and in leachates of pore-water salts from dried core samples, both from boreholes in the Tptp. Strontium isotope ratios ({sup 87}Sr/{sup 86}Sr) vary systematically with depth in the surface-based boreholes. Ratios in pore water near the surface (0.7114 to 0.7124) reflect the range of ratios in soil carbonate (0.7112 to 0.7125) collected near the boreholes, but ratios in the Tptp (0.7122 to 0.7127) at depths of 150 to 370 m have a narrower range and are more radiogenic due to interaction with the volcanic rocks (primarily non-welded tuffs) above the Tptp. An advection-reaction model relates the rate of strontium dissolution from the rocks with flow velocity. The model results agree with the low transport velocity ({approx}2 cm per year) calculated from carbon-14 data by I.C. Yang (2002, App. Geochem., v. 17, no. 6, p. 807-817). Strontium isotope ratios in pore water from Tptp samples from horizontal boreholes collared in tunnels at …
Date: February 19, 2004
Creator: Marshall, B. & Futa, K.
Object Type: Report
System: The UNT Digital Library
Heat Transfer Analysis for a Fixed CST Column (open access)

Heat Transfer Analysis for a Fixed CST Column

In support of a small column ion exchange (SCIX) process for the Savannah River Site waste processing program, a transient two-dimensional heat transfer model that includes the conduction process neglecting the convection cooling mechanism inside the crystalline silicotitanate (CST) column has been constructed and heat transfer calculations made for the present design configurations. For this situation, a no process flow condition through the column was assumed as one of the reference conditions for the simulation of a loss-of-flow accident. A series of the modeling calculations has been performed using a computational heat transfer approach. Results for the baseline model indicate that transit times to reach 130 degrees Celsius maximum temperature of the CST-salt solution column are about 96 hours when the 20-in CST column with 300 Ci/liter heat generation source and 25 degrees Celsius initial column temperature is cooled by natural convection of external air as a primary heat transfer mechanism. The modeling results for the 28-in column equipped with water jacket systems on the external wall surface of the column and water coolant pipe at the center of the CST column demonstrate that the column loaded with 300 Ci/liter heat source can be maintained non-boiling indefinitely. Sensitivity calculations for …
Date: February 19, 2004
Creator: Lee, Si Young
Object Type: Report
System: The UNT Digital Library
Microwave Imaging Reflectometry for the Measurement of Turbulent Fluctuations in Tokamaks (open access)

Microwave Imaging Reflectometry for the Measurement of Turbulent Fluctuations in Tokamaks

This article describes a numerical study of microwave reflectometry for the measurement of turbulent fluctuations in tokamak-like plasmas with a cylindrical geometry. Similarly to what was found previously in plane-stratified plasmas, the results indicate that the characteristics of density fluctuations cannot be uniquely determined from the reflected waves if the latter are allowed to propagate freely to the point of detection, as in standard reflectometry. Again, we find that if the amplitude of fluctuations is below a threshold that is set by the spectrum of poloidal wave numbers, the local characteristics of density fluctuations can be obtained from the phase of reflected waves when these are collected with a wide aperture antenna, and an image of the cutoff is formed onto an array of phase-sensitive detectors.
Date: February 19, 2004
Creator: Mazzucato, E.
Object Type: Report
System: The UNT Digital Library
Roller Burnishing - A Cold Working Tool to Reduce Weld Induced Residual Stress (open access)

Roller Burnishing - A Cold Working Tool to Reduce Weld Induced Residual Stress

The possibility of stress corrosion cracking (SCC) in regions of tensile residual stress introduced by weld deposited material has been a concern where environmental effects can reduce component life. Roller burnishing, a form of mechanical cold-working, has been considered as a means of providing for residual stress state improvements. This paper provides a computational evaluation of the roller burnishing process to address the permanent deformation needed to introduce a desirable residual stress state. The analysis uses a series of incrementally applied pressure loadings and finite element methodology to simulate the behavior of a roller burnishing tool. Various magnitudes of applied pressure loadings coupled with different size plates and boundary conditions are examined to assess the degree and depth of the residual compressive stress state after cold working. Both kinematic and isotropic hardening laws are evaluated.
Date: February 19, 2002
Creator: Martin, John
Object Type: Report
System: The UNT Digital Library
Anomalous Skin Effect for Anisotropic Electron Velocity Distribution Function (open access)

Anomalous Skin Effect for Anisotropic Electron Velocity Distribution Function

The anomalous skin effect in a plasma with a highly anisotropic electron velocity distribution function (EVDF) is very different from skin effect in a plasma with the isotropic EVDF. An analytical solution was derived for the electric field penetrated into plasma with the EVDF described as a Maxwellian with two temperatures Tx >> Tz, where x is the direction along the plasma boundary and z is the direction perpendicular to the plasma boundary. The skin layer was found to consist of two distinctive regions of width of order nTx/w and nTz/w, where nTx,z/w = (Tx,z/m)1/2 is the thermal electron velocity and w is the incident wave frequency.
Date: February 19, 2004
Creator: Kaganovich, Igor; Startsev, Edward & Shvets, Gennady
Object Type: Report
System: The UNT Digital Library
An Innovative Ceramic Corrosion Protection System for Zircaloy Cladding (open access)

An Innovative Ceramic Corrosion Protection System for Zircaloy Cladding

Light Water reactor (LWR) fuel performance is currently limited by thermal, chemical and mechanical constraints associated with the design, fabrication, and operation of the fuel in incore operation. Corrosion of the zirconium based (Zircaloy-4) alloy cladding of the fuel is a primary limiting factor. Recent success at the University of Florida in developing thin ceramic films with great adhesive properties for metal substrates offers an innovative breakthrough for eliminating a major weakness of the Zircaloy clad. ?The University of Florida proposes to coat the existing Zircaloy clad tubes with a ceramic coating for corrosion protection. An added bonus of this approach would be the implementation of a boron-containing burnable poison outer layer will also be demonstrated as part of the ceramic coating development. In this proposed effort, emphasis will be on the ceramic coating with only demonstration of feasibility on the burnable outer coating approach. This proposed program i s expected to give a step change (approximately a doubling) in clad lifetime before failure due to corrosion. In the development of ceramic coatings for Zircaloy-4 clad, silicon carbide and zirconium carbide coatings will first be applied to Zircaloy-4 coupons and cladding samples by thermal assisted chemical vapor deposition, plasma assisted …
Date: February 19, 2003
Creator: Baney, Ronald H.; Tulenko, James S.; Butt, D.; Demkowicz, P.; Fuchs, G.; Schoessow, G. et al.
Object Type: Report
System: The UNT Digital Library
Technical Status Report for US Wind Farmers Network (open access)

Technical Status Report for US Wind Farmers Network

The theme of the work in this quarter was community-based wind and locally owned wind projects. The work Windustry has done is just beginning to touch the heart of the matter for a hugely interested audience of rural landowners and rural communities. We revised and published a Windustry Newsletter on two farmer owned wind projects called Minwind I and Minwind II. This article was largely researched and written last quarter but the principal individuals that organized the wind projects didn't want any more farmers calling them up than they already had, so they urged us to put a hold on the article or not publish it. This presented a unique problem for Windustry. Up to this point, we had not dealt with generating too much attention for a wind energy project. The story of a group of farmers and individuals pooling their resources for two locally owned commercial-scale wind projects is very compelling and the organizers of the projects were getting a great deal of attention from other farmers that want more details on the project. However, the organizers committed a large amount of their own resources toward the set up of this project which took many hours with their …
Date: February 19, 2003
Creator: Daniels, Lisa
Object Type: Report
System: The UNT Digital Library
Stodolsky's theorem and neutrino oscillation phases-for pedestrians. (open access)

Stodolsky's theorem and neutrino oscillation phases-for pedestrians.

Neutrino oscillations are experimentally observable only as a result of interference between neutrino states with different masses and the same energy. All interference effects between neutrino states having different energies are destroyed by the interaction between the incident neutrino and the neutrino detector. Erroneous results are frequently obtained by neglecting the neutrino-detector interactions.
Date: February 19, 2003
Creator: Lipkin, H. J.
Object Type: Report
System: The UNT Digital Library
Electron proton two-stream instability at the PSR. (open access)

Electron proton two-stream instability at the PSR.

A strong, fast, transverse instability has long been observed at the Los Alamos Proton Storage Ring (PSR) where it is a limiting factor on peak intensity. Most of the available evidence, based on measurements of the unstable proton beam motion, is consistent with an electron-proton two-stream instability. The need for higher beam intensity at PSR [1] and for future high-intensity, proton drivers has motivated a multi-lab collaboration (LANL, ANL, FNAL, LBNL, BNL, ORNL, and PPPL) to coordinate research on the causes, dynamics and cures for this instability. Important characteristics of the electron cloud were recently measured with retarding field electron analyzers and various collection electrodes. Suppression of the electron cloud formation by TiN coatings has confirmed the importance of secondary emission processes in its generation. New tests of potential controls included dual harmonic rf, damping by higher order multipoles, damping by X,Y coupling and the use of inductive inserts to compensate longitudinal space charge forces. With these controls and higher rf voltage the PSR has accumulated stable beam intensity up to 9.7 {micro}C/pulse (6 x 10{sup 13} protons), which is a 60% increase over the previous maximum.
Date: February 19, 2002
Creator: Macek, R. J.; Browman, A.; Fitzgerald, D.; McCrady, R.; Merrill, F.; Plum, M. et al.
Object Type: Article
System: The UNT Digital Library
Evaluation of Mass Transfer Performance for Caustic-Side Solvent Extraction of Cesium in a Conventional 5-cm Centrifugal Contactor (open access)

Evaluation of Mass Transfer Performance for Caustic-Side Solvent Extraction of Cesium in a Conventional 5-cm Centrifugal Contactor

Tests have been conducted to determine if satisfactory mass transfer performance is achieved using a fully pumping 5-cm centrifugal contactor under conditions present in the Caustic-Side Solvent Extraction (CSSX) process. Tests utilized a commercially available contactor that had been modified by installation of a rotor housing bottom that had straight radial vanes on the process side. As received from the vendor, the housing bottom was equipped with curved (impeller-type) vanes that were intended to promote phase separation by minimizing mixing of influent solutions. Stage efficiencies exceeding 85% were obtained under conditions, present in the extraction section of the CSSX flowsheet. Under CSSX stripping conditions the stage efficiency exceeded 90%. In both cases, the efficiencies obtained exceed the minimum requirement for acceptable transfer of cesium in the CSSX process.
Date: February 19, 2002
Creator: Birdwell, Jr. J.F.
Object Type: Report
System: The UNT Digital Library
Impurity leaching rates of 1000 liter growth tanks (open access)

Impurity leaching rates of 1000 liter growth tanks

This memo reports on the analysis of some recent measurements of solution impurity levels in the three KDP and one DKDP Pilot Production 1000 liter growth tanks (Tanks B, C, D, & F). Solution samples were taken on a weekly basis during recent crystal growth runs in each tank and were analyzed by inductively coupled plasma emission spectroscopy (ICP-ES). The solution history for five specific elements, Si, B, Al, Fe and Ca will be analyzed in detail. The first four of these elements are input into solution via slow dissolution of the glass vessel at a rate which is strongly dependent on the solution temperature. Si and B continuously accumulate in solution, since they are not incorporated into the crystal. Al and Fe by comparison are incorporated into the crystal (primarily the prismatic sectors) and present problems to inclusion-free growth (Al) and 30 damage (Fe). The level of these impurities initially increases when the crystal size is small but later decreases when the rate of incorporation into the crystal exceeds the rate of dissolution of the glass tank. The last element, Ca is of interest since it has recently been observed to be one of the elements found at the …
Date: February 19, 1999
Creator: Burnham, A; Floyd, R; Robey, H F & Torres, R
Object Type: Report
System: The UNT Digital Library
Development of an Initial Simulant for the Idaho Tank Farm Solids (open access)

Development of an Initial Simulant for the Idaho Tank Farm Solids

The goal of this task was to develop the methodology for producing a suitable simulant for waste solids and the fabrication of an initial simulant for use in the demonstrations and testing performed as part of the down-select process for disposition of INTEC tank waste. The analytical results from WM-182 and WM-183 tank samples were used as the basis for this work.
Date: February 19, 2003
Creator: Harbour, J.R.
Object Type: Report
System: The UNT Digital Library
Simulating the Visual Performance of Electrochromic Glazing for Solar Control (open access)

Simulating the Visual Performance of Electrochromic Glazing for Solar Control

None
Date: February 19, 1997
Creator: Ehrlich, Charles
Object Type: Article
System: The UNT Digital Library
Measurement of Gas and Liquid Velocities in an Air-Water Two-Phase Flow using Cross-Correlation of Signals from a Double Senor Hot-Film Probe (open access)

Measurement of Gas and Liquid Velocities in an Air-Water Two-Phase Flow using Cross-Correlation of Signals from a Double Senor Hot-Film Probe

Local gas and liquid velocities are measured by cross-correlating signals from a double sensor hot-film anemometer probe in pure water flow and air water two-phase flow. The gas phase velocity measured in two-phase flow agrees with velocity data obtained using high-speed video to within +/-5%. A turbulent structure, present in the liquid phase, allows a correlation to be taken, which is consistent with the expected velocity profiles in pure liquid flow. This turbulent structure is also present in the liquid phase of a two-phase flow system. Therefore, a similar technique can be applied to measure the local liquid velocity in a two-phase system, when conditions permit.
Date: February 19, 2002
Creator: Gurau, B.; Vassalo, P. & Keller, K.
Object Type: Report
System: The UNT Digital Library