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Smart Screening System (S3) In Taconite Processing
The conventional screening machines used in processing plants have had undesirable high noise and vibration levels. They also have had unsatisfactorily low screening efficiency, high energy consumption, high maintenance cost, low productivity, and poor worker safety. These conventional vibrating machines have been used in almost every processing plant. Most of the current material separation technology uses heavy and inefficient electric motors with an unbalanced rotating mass to generate the shaking. In addition to being excessively noisy, inefficient, and high-maintenance, these vibrating machines are often the bottleneck in the entire process. Furthermore, these motors, along with the vibrating machines and supporting structure, shake other machines and structures in the vicinity. The latter increases maintenance costs while reducing worker health and safety. The conventional vibrating fine screens at taconite processing plants have had the same problems as those listed above. This has resulted in lower screening efficiency, higher energy and maintenance cost, and lower productivity and workers safety concerns. The focus of this work is on the design of a high performance screening machine suitable for taconite processing plants. SmartScreens{trademark} technology uses miniaturized motors, based on smart materials, to generate the shaking. The underlying technologies are Energy Flow Control{trademark} and Vibration Control …
Date:
March 1, 2005
Creator:
Allaei, Daryoush; Mohammed, Asim Syed; Tarnowski, David & Morison, Angus
Object Type:
Report
System:
The UNT Digital Library
Smart Screening System (S3) In Taconite Processing
The conventional screening machines used in processing plants have had undesirable high noise and vibration levels. They also have had unsatisfactorily low screening efficiency, high energy consumption, high maintenance cost, low productivity, and poor worker safety. These conventional vibrating machines have been used in almost every processing plant. Most of the current material separation technology uses heavy and inefficient electric motors with an unbalanced rotating mass to generate the shaking. In addition to being excessively noisy, inefficient, and high-maintenance, these vibrating machines are often the bottleneck in the entire process. Furthermore, these motors, along with the vibrating machines and supporting structure, shake other machines and structures in the vicinity. The latter increases maintenance costs while reducing worker health and safety. The conventional vibrating fine screens at taconite processing plants have had the same problems as those listed above. This has resulted in lower screening efficiency, higher energy and maintenance cost, and lower productivity and workers safety concerns. The focus of this work is on the design of a high performance screening machine suitable for taconite processing plants. SmartScreens{trademark} technology uses miniaturized motors, based on smart materials, to generate the shaking. The underlying technologies are Energy Flow Control{trademark} and Vibration Control …
Date:
March 1, 2006
Creator:
Allaei, Daryoush; Wartman, Ryan; Tarnowski, David & Mohammed, Asim Syed
Object Type:
Report
System:
The UNT Digital Library
Les Houches Physics at TeV Colliders 2005 Beyond the Standard Model Working Group: Summary Report
The work contained herein constitutes a report of the ''Beyond the Standard Model'' working group for the Workshop ''Physics at TeV Colliders'', Les Houches, France, 2-20 May, 2005. We present reviews of current topics as well as original research carried out for the workshop. Supersymmetric and non-supersymmetric models are studied, as well as computational tools designed in order to facilitate their phenomenology.
Date:
March 17, 2006
Creator:
Allanach, B. C.; Grojean, C.; Skands, P.; Accomando, E.; Azuelos, G.; Baer, H. et al.
Object Type:
Article
System:
The UNT Digital Library
Results of the 2007 B100 Quality Survey
In a 2007 analysis of samples from 52% of U.S. biodiesel (B100) producers, 90% met ASTM and other specifications for critical engine performance properties and for elements that harm emission controls.
Date:
March 1, 2008
Creator:
Alleman, T. L. & McCormick, R. L.
Object Type:
Report
System:
The UNT Digital Library
Highways of a Global Traveler: Tracking Tropospheric Ozone
On the stage of global change, ozone plays the role of both hero and villain. This brief document discusses about the tracking of Tropospheric Ozone, where ozone forms and where it travels have become key concerns for international health and economic policy-making.
Date:
March 22, 2002
Creator:
Allen, Jeannie & Simmon, Robert
Object Type:
Text
System:
The UNT Digital Library
Fresh and Spent Nuclear Fuel Repatriation from the IRT-2000 Research Reactor Facility, Sofia, Bulgaria
The IRT 2000 research reactor, operated by the Bulgarian Institute for Nuclear Research and Nuclear Energy (INRNE), safely shipped all of their Russian-origin nuclear fuel from the Republic of Bulgaria to the Russian Federation beginning in 2003 and completing in 2008. These fresh and spent fuel shipments removed all highly enriched uranium (HEU) from Bulgaria. The fresh fuel was shipped by air in December 2003 using trucks and a commercial cargo aircraft. One combined spent fuel shipment of HEU and low enriched uranium (LEU) was completed in July 2008 using high capacity VPVR/M casks transported by truck, barge, and rail. The HEU shipments were assisted by the Russian Research Reactor Fuel Return Program (RRRFR) and the LEU spent fuel shipment was funded by Bulgaria. This report describes the work, approvals, organizations, equipment, and agreements required to complete these shipments and concludes with several major lessons learned.
Date:
March 1, 2009
Creator:
Allen, K. J.; Apostolov, T. G. & Dimitrov, I. S.
Object Type:
Article
System:
The UNT Digital Library
Laser Ion Acceleration from the Interaction of Ultra-Intense laser Pulse with thi foils
The discovery that ultra-intense laser pulses (I > 10{sup 18} W/cm{sup 2}) can produce short pulse, high energy proton beams has renewed interest in the fundamental mechanisms that govern particle acceleration from laser-solid interactions. Experiments have shown that protons present as hydrocarbon contaminants on laser targets can be accelerated up to energies > 50 MeV. Different theoretical models that explain the observed results have been proposed. One model describes a front-surface acceleration mechanism based on the ponderomotive potential of the laser pulse. At high intensities (I > 10{sup 18} W/cm{sup 2}), the quiver energy of an electron oscillating in the electric field of the laser pulse exceeds the electron rest mass, requiring the consideration of relativistic effects. The relativistically correct ponderomotive potential is given by U{sub p} = ([1 + I{lambda}{sup 2}/1.3 x 10{sup 18}]{sup 1/2} - 1) m{sub o}c{sup 2}, where I{lambda}{sup 2} is the irradiance in W{micro}m{sup 2}/cm{sup 2} and m{sub o}c{sup 2} is the electron rest mass.At laser irradiance of I{lambda}{sup 2} {approx} 10{sup 20} W{micro}m{sup 2}/cm{sup 2}, the ponderomotive potential can be of order several MeV. A few recent experiments--discussed in Chapter 3 of this thesis--consider this ponderomotive potential sufficiently strong to accelerate protons from the …
Date:
March 12, 2004
Creator:
Allen, M
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Working at Congress : a Sandian's experience.
During the 110th Congress (calendar years 2007 and 2008), Matthew Allen, a Sandian nuclear scientist, served as a Congressional Fellow on the Committee on Homeland Security in the House of Representatives. This report is an informative account of the role staffers play in assisting the members of Congress in their oversight and legislative duties. It is also a personal account of Matthew Allen's experience as a committee staffer in the House of Representatives.
Date:
March 1, 2009
Creator:
Allen, Matthew
Object Type:
Report
System:
The UNT Digital Library
Direct Experimental Evidence of Back-Surface Acceleration from Laser-Irradiated Foils
Au foils were irradiated with a 100-TW, 100-fs laser at intensities greater than 10{sup 20} W/cm{sup 2} producing proton beams with a total yield of {approx} 10{sup 11} and maximum proton energy of > 9 MeV. Removing contamination from the back surface of Au foils with an Ar-ion sputter gun reduced the total yield of accelerated protons to less than 1% of the yield observed without removing contamination. Removing contamination the front surface (laser-interaction side) of the target had no observable effect on the proton beam. We present a one-dimensional particle-in-cell simulation that models the experiment. Both experimental and simulation results are consistent with the back-surface acceleration mechanism described in the text.
Date:
March 29, 2004
Creator:
Allen, Matthew; Patel, Pravesh K.; Mackinnon, Andrew; Price, Dwight; Wilks, Scott & Morse, Edward
Object Type:
Article
System:
The UNT Digital Library
Tanks Focus Area Site Needs Assessment FY 2000
This document summarizes the Tanks Focus Area (TFA's) process of collecting, analyzing, and responding to high-level radioactive tank waste science and technology needs developed from across the DOE complex in FY 2000. The document also summarizes each science and technology need, and provides an initial prioritization of TFA's projected work scope for FY 2001 and FY 2002.
Date:
March 10, 2000
Creator:
Allen, Robert W.
Object Type:
Report
System:
The UNT Digital Library
Evaluation of ITER MSE Viewing Optics
The Motional Stark Effect (MSE) diagnostic on ITER determines the local plasma current density by measuring the polarization angle of light resulting from the interaction of a high energy neutral heating beam and the tokamak plasma. This light signal has to be transmitted from the edge and core of the plasma to a polarization analyzer located in the port plug. The optical system should either preserve the polarization information, or it should be possible to reliably calibrate any changes induced by the optics. This LLNL Work for Others project for the US ITER Project Office (USIPO) is focused on the design of the viewing optics for both the edge and core MSE systems. Several design constraints were considered, including: image quality, lack of polarization aberrations, ease of construction and cost of mirrors, neutron shielding, and geometric layout in the equatorial port plugs. The edge MSE optics are located in ITER equatorial port 3 and view Heating Beam 5, and the core system is located in equatorial port 1 viewing heating beam 4. The current work is an extension of previous preliminary design work completed by the ITER central team (ITER resources were not available to complete a detailed optimization of …
Date:
March 26, 2007
Creator:
Allen, S.; Lerner, S.; Morris, K.; Jayakumar, J.; Holcomb, C.; Makowski, M. et al.
Object Type:
Report
System:
The UNT Digital Library
Groundwater Level Status Report for Fiscal Year 2006 Los Alamos National Laboratory
The status of groundwater level monitoring at Los Alamos National Laboratory in Fiscal Year 2006 is provided in this report. The Groundwater Level Monitoring Project was instituted in 2005 for providing a framework for the collection and processing of quality controlled groundwater level data. This report summarizes groundwater level data for 158 monitoring wells, including 43 regional aquifer wells, 23 intermediate wells, and 92 alluvial wells. Pressure transducers were installed in 132 monitoring wells for continuous monitoring of groundwater levels. Time-series hydrographs of groundwater level data are presented along with pertinent construction and location information for each well.
Date:
March 30, 2007
Creator:
Allen, Shannon P. & Koch, Richard J.
Object Type:
Report
System:
The UNT Digital Library
The Relation Between Accretion Rate And Jet Power in X-Ray Luminous Elliptical Galaxies
Using Chandra X-ray observations of nine nearby, X-ray luminous elliptical galaxies with good optical velocity dispersion measurements, we show that a tight correlation exists between the Bondi accretion rates calculated from the observed gas temperature and density profiles and estimated black hole masses, and the power emerging from these systems in relativistic jets. The jet powers, which are inferred from the energies and timescales required to inflate cavities observed in the surrounding X-ray emitting gas, can be related to the accretion rates using a power law model of the form log (P{sub Bondi}/10{sup 43} erg s{sup -1}) = A + B log (P{sub jet}/10{sup 43} erg s{sup -1}), with A = 0.62 {+-} 0.15 and B = 0.77 {+-} 0.18. Our results show that a significant fraction of the energy associated with the rest mass of material entering the Bondi accretion radius (2.4{sub -0.7}{sup +1.0} per cent, for P{sub jet} = 10{sup 43} erg s{sup -1}) eventually emerges in the relativistic jets. Our results have significant implications for studies of accretion, jet formation and galaxy formation. The observed tight correlation suggests that the Bondi formulae provide a reasonable description of the accretion process in these systems, despite the likely presence …
Date:
March 10, 2006
Creator:
Allen, Steven W.; Dunn, R. J. H.; Fabian, A. C.; Taylor, G. B. & Reynolds, C. S.
Object Type:
Report
System:
The UNT Digital Library
Complex Flows by Nanohydrodynamics
The study of complex flows by particle simulations is speeded up over molecular dynamics (MD) by more than two orders of magnitude by employing a stochastic collision dynamics method (DSMC) extended to high density (CBA). As a consequence, a picture generated on a single processor shows the typical features of the Rayleigh-Taylor instability and is in quantitative agreement with the experimentally found long time behavior.
Date:
March 1, 2004
Creator:
Alley, E; Covello, P & Alder, B
Object Type:
Article
System:
The UNT Digital Library
Doctoral Recital: 2006-03-20 – Anthony Allgeier, clarinet
Recital presented at the UNT College of Music Concert Hall in partial fulfillment of the Doctor of Musical Arts (DMA) degree
Date:
March 20, 2006
Creator:
Allgeier, Anthony
Object Type:
Sound
System:
The UNT Digital Library
Fluorescence Rise Time Measurements for High Temperature Fluorescence-Based Thermometry
Certain ceramic-like phosphor materials exhibit bright fluorescence with a pronounced temperature dependence over a range which spans the cryogenic to 1700 C, depending on the specific phosphor. To measure temperature, a surface, for instance a turbine blade, is coated with the material. An optical system, sometimes including optical fibers, conveys stimulating light and collects the emission for analysis. Either emission intensity or decay time may indicate temperature. Previously fielded tests have involved surfaces such as blades, vanes, pistons, in-take valves, sheets of galvanneal steel, etc. The fluorescent coatings may be applied to small parts via sputtering methods or to large areas by mixture with inorganic binders. Presented here are results characterizing fluorescence rise times as a means of determining temperature from ambient to 700 C for Y{sub 2}O{sub 3}:Eu.
Date:
March 24, 2005
Creator:
Allison, S.W.
Object Type:
Report
System:
The UNT Digital Library
Sub-Microsecond Decay Time Phosphors for Pressure Sensitive Paint Applications
The results suggest that garnet phosphors can be engineered to function thermographically over desired temperature ranges by adjusting gallium content. Substituting gadolinium for the yttrium in the host matrix also has an effect but it is not as large. A silicate phosphor showed the greatest temperature dependence though it could not be excited to fluoresce by a blue LED. All the garnet phosphors could be excited with such a blue source. Two phosphors tested showed an increase in intensity with temperature. Other garnet and silicate materials as mentioned above will be tested in the future. In addition, some perovskite phosphors, such as GdAlO{sub 3}:Ce, will also be investigated.
Date:
March 22, 2001
Creator:
Allison, S.W.
Object Type:
Article
System:
The UNT Digital Library
ORNL/IAT ARMATURE DIAGNOSTICS DEMONSTRATION TEST REPORT
This test established feasibility for 'on the fly' temperature measurements of rail gun projectiles. In addition, an approach for projectile velocity measurement was also demonstrated. Insight was gained into other useful optical and fiberoptic diagnostic approaches. Instantaneous diagnostics could be critical for achieving further improvements in rail gun operation. They have the potential to enable design enhancements by providing information on the state of the armature and its relationship to the rail as it proceeds down the bore. To that end, the following was accomplished: (1) Optical fibers successfully delivered optical excitation and returned reflective and fluorescence signals as desired. (2) Luminescent coatings survived multiple firings--approximately 40 shots. (3) Optical triggering effectively synchronized an ultraviolet laser pulse to strike the moving armature. (4) Velocity measurements were successfully accomplished by either triggering on the armature front edge using two red diode lasers or by using a single laser and grooved marks a known distance apart on the armature surface. (5) Velocities ranged from 19 to 88 m/s. (6) Temperatures of 30 to 92 C were measured with a precision of about 2 C-: (a) This precision was achieved with a single laser shot and (b) Motion effect was observed but a …
Date:
March 1, 2005
Creator:
Allison, Stephen W; Cates, Michael R; Goedeke, Shawn; Crawford, M. T.; Ferraro, S. B. & Akerman, A.
Object Type:
Report
System:
The UNT Digital Library
Low Mach Number Modeling of Type Ia Supernovae. II. EnergyEvolution
The convective period leading up to a Type Ia supernova (SNIa) explosion is characterized by very low Mach number flows, requiringhydrodynamical methods well-suited to long-time integration. We continuethe development of the low Mach number equation set for stellar scaleflows by incorporating the effects of heat release due to externalsources. Low Mach number hydrodynamics equations with a time-dependentbackground state are derived, and a numerical method based on theapproximate projection formalism is presented. We demonstrate throughvalidation with a fully compressible hydrodynamics code that this lowMach number model accurately captures the expansion of the stellaratmosphere as well as the local dynamics due to external heat sources.This algorithm provides the basis for an efficient simulation tool forstudying the ignition of SNe Ia.
Date:
March 28, 2006
Creator:
Almgren, Ann S.; Bell, John B.; Rendleman, Charles A. & Zingale,Mike
Object Type:
Article
System:
The UNT Digital Library
Development of a National Center for Hydrogen Technology
In November 2005, the Energy & Environmental Research Center (EERC), ePowerSynergies, Inc. (ePSI), and Resurfice Corporation teamed to develop, produce, and demonstrate the world's first and only fuel cell-powered ice resurfacer. The goals of this project were: {sm_bullet} To educate the public on the readiness, practicality, and safety of fuel cells powered by hydrogen fuel and {sm_bullet} To establish a commercialization pathway in an early-adopter, niche market. The vehicle was developed and produced in a short 3-month span. The vehicle made its world debut at U.S. Senator Byron Dorgan's (D-ND) 2005 Hydrogen Energy Action Summit. Subsequently, the vehicle toured North America appearing at numerous public events and conferences, receiving much attention from international media outlets.
Date:
March 1, 2007
Creator:
Almlie, Jay C.; Wood, Bruce & Schlupp, Rich
Object Type:
Report
System:
The UNT Digital Library
Quasar H II Regions During Cosmic Reionization
Cosmic reionization progresses as HII regions form around sources of ionizing radiation. Their average size grows continuously until they percolate and complete reionization. We demonstrate how this typical growth can be calculated around the largest, biased sources of UV emission such as quasars by further developing an analytical model based on the excursion set formalism. This approach allows us to calculate the sizes and growth of the HII regions created by the progenitors of any dark matter halo of given mass and redshift with a minimum of free parameters. Statistical variations in the size of these pre-existing HII regions are an additional source of uncertainty in the determination of very high redshift quasar properties from their observed HII region sizes. We use this model to demonstrate that the transmission gaps seen in very high redshift quasars can be understood from the radiation of only their progenitors and associated clustered small galaxies. The fit requires the epoch of overlap to be at z = 5.8 {+-} 0.1. This interpretation makes the transmission gaps independent of the age of the quasars observed. If this interpretation were correct it would raise the prospects of using radio interferometers currently under construction to detect the …
Date:
March 30, 2007
Creator:
Alvarez, Marcelo A.; Abel, Tom & /KIPAC, Menlo Park
Object Type:
Article
System:
The UNT Digital Library
Oral History Interview with Abelino Alviar, March 14, 2003
The National Museum of the Pacific War presents an interview with Abelino Alviar. Alviar joined the Army in May of 1944. In early 1945, he joined the 778th Anti-aircraft Artillery Automatic Weapons Battalion. They deployed to Le Havre, France, and traveled to Munich, Germany, arriving after the Battle of the Ardennes. Alviar provided guard duty, and served as a gunner on the half-track supporting the 1st Infantry Division as they fought into Germany. He also worked as a translator and helped transport supplies to the front line. He returned home and was discharged in May of 1946.
Date:
March 14, 2003
Creator:
Alviar, Abelino
Object Type:
Sound
System:
The Portal to Texas History
Oral History Interview with Abelino Alviar, March 14, 2003
The National Museum of the Pacific War presents an interview with Abelino Alviar. Alviar joined the Army in May of 1944. In early 1945, he joined the 778th Anti-aircraft Artillery Automatic Weapons Battalion. They deployed to Le Havre, France, and traveled to Munich, Germany, arriving after the Battle of the Ardennes. Alviar provided guard duty, and served as a gunner on the half-track supporting the 1st Infantry Division as they fought into Germany. He also worked as a translator and helped transport supplies to the front line. He returned home and was discharged in May of 1946.
Date:
March 14, 2003
Creator:
Alviar, Abelino
Object Type:
Text
System:
The Portal to Texas History
Mechanical considerations and design skills.
The purpose of the report is to provide experienced-based insights into design processes that will benefit designers beginning their employment at Sandia National Laboratories or those assuming new design responsibilities. The main purpose of this document is to provide engineers with the practical aspects of system design. The material discussed here may not be new to some readers, but some of it was to me. Transforming an idea to a design to solve a problem is a skill, and skills are similar to history lessons. We gain these skills from experience, and many of us have not been fortunate enough to grow in an environment that provided the skills that we now need. I was fortunate to grow up on a farm where we had to learn how to maintain and operate several different kinds of engines and machines. If you are like me, my formal experience is partially based upon the two universities from which I graduated, where few practical applications of the technologies were taught. What was taught was mainly theoretical, and few instructors had practical experience to offer the students. I understand this, as students have their hands full just to learn the theoretical. The practical part …
Date:
March 1, 2008
Creator:
Alvis, Robert L.
Object Type:
Report
System:
The UNT Digital Library