High-density carbon (HDC) capsule designs for a- heating and for ignition (open access)

High-density carbon (HDC) capsule designs for a- heating and for ignition

None
Date: August 29, 2013
Creator: Ho, D
Object Type: Article
System: The UNT Digital Library
High-Spin Cobalt Hydrides for Catalysis (open access)

High-Spin Cobalt Hydrides for Catalysis

Organometallic chemists have traditionally used catalysts with strong-field ligands that give low-spin complexes. However, complexes with a weak ligand field have weaker bonds and lower barriers to geometric changes, suggesting that they may lead to more rapid catalytic reactions. Developing our understanding of high-spin complexes requires the use of a broader range of spectroscopic techniques, but has the promise of changing the mechanism and/or selectivity of known catalytic reactions. These changes may enable the more efficient utilization of chemical resources. A special advantage of cobalt and iron catalysts is that the metals are more abundant and cheaper than those currently used for major industrial processes that convert unsaturated organic molecules and biofeedstocks into useful chemicals. This project specifically evaluated the potential of high-spin cobalt complexes for small-molecule reactions for bond rearrangement and cleavage reactions relevant to hydrocarbon transformations. We have learned that many of these reactions proceed through crossing to different spin states: for example, high-spin complexes can flip one electron spin to access a lower-energy reaction pathway for beta-hydride elimination. This reaction enables new, selective olefin isomerization catalysis. The high-spin cobalt complexes also cleave the C-O bond of CO2 and the C-F bonds of fluoroarenes. In each case, the …
Date: August 29, 2013
Creator: Holland, Patrick L.
Object Type: Report
System: The UNT Digital Library
Science and Technology Review October/November 2013 (open access)

Science and Technology Review October/November 2013

None
Date: August 29, 2013
Creator: Simon, A. J.
Object Type: Report
System: The UNT Digital Library
A Study of Application-Level Recovery Methods for Transient Network Faults (open access)

A Study of Application-Level Recovery Methods for Transient Network Faults

None
Date: August 29, 2013
Creator: Laguna, I; Leon, E A; Schulz, M & Stephenson, M
Object Type: Article
System: The UNT Digital Library
Waste Treatment Technology Process Development Plan For Hanford Waste Treatment Plant Low Activity Waste Recycle (open access)

Waste Treatment Technology Process Development Plan For Hanford Waste Treatment Plant Low Activity Waste Recycle

The purpose of this Process Development Plan is to summarize the objectives and plans for the technology development activities for an alternative path for disposition of the recycle stream that will be generated in the Hanford Waste Treatment Plant Low Activity Waste (LAW) vitrification facility (LAW Recycle). This plan covers the first phase of the development activities. The baseline plan for disposition of this stream is to recycle it to the WTP Pretreatment Facility, where it will be concentrated by evaporation and returned to the LAW vitrification facility. Because this stream contains components that are volatile at melter temperatures and are also problematic for the glass waste form, they accumulate in the Recycle stream, exacerbating their impact on the number of LAW glass containers. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and reducing the halides in the Recycle is a key component of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, this stream does not have a proven disposition path, and resolving this gap becomes vitally important. …
Date: August 29, 2013
Creator: McCabe, Daniel J.; Wilmarth, William R. & Nash, Charles A.
Object Type: Report
System: The UNT Digital Library
Agreement Between Local and Global Measurements of the London Penetration Depth (open access)

Agreement Between Local and Global Measurements of the London Penetration Depth

Recent measurements of the superconducting penetration depth in Ba(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2} appeared to disagree on the magnitude and curvature of {delta}{lambda}{sub ab}(T), even near optimal doping. These measurements were carried out on different samples grown by different groups. To understand the discrepancy, we use scanning SQUID susceptometry and a tunnel diode resonator to measure the penetration depth in a single sample. The penetration depth observed by the two techniques is identical with no adjustments. We conclude that any discrepancies arise from differences between samples, either in growth or crystal preparation.
Date: August 29, 2012
Creator: Lippman, Thomas M.; Kalisky, Beena; Kim, Hyunsoo; Tanatar, Makariy; Budko, Sergey L.; Canfield, Paul C. et al.
Object Type: Article
System: The UNT Digital Library
ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT #46000524120 (open access)

ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT #46000524120

Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The Harrell Industries Lot No.46000524120 qualification and the 14 verification samples met each of the selected specification requirements that were tested and, consequently, the material is acceptable for use in the ARP process.
Date: August 29, 2012
Creator: Taylor-Pashow, K.
Object Type: Report
System: The UNT Digital Library
CHEMICAL DIFFERENCES BETWEEN SLUDGE SOLIDS AT THE F AND H AREA TANK FARMS (open access)

CHEMICAL DIFFERENCES BETWEEN SLUDGE SOLIDS AT THE F AND H AREA TANK FARMS

The primary source of waste solids received into the F Area Tank Farm (FTF) was from PUREX processing performed to recover uranium and plutonium from irradiated depleted uranium targets. In contrast, two primary sources of waste solids were received into the H Area Tank Farm (HTF): a) waste from PUREX processing; and b) waste from H-modified (HM) processing performed to recover uranium and neptunium from burned enriched uranium fuel. Due to the differences between the irradiated depleted uranium targets and the burned enriched uranium fuel, the average compositions of the F and H Area wastes are markedly different from one another. Both F and H Area wastes contain significant amounts of iron and aluminum compounds. However, because the iron content of PUREX waste is higher than that of HM waste, and the aluminum content of PUREX waste is lower than that of HM waste, the iron to aluminum ratios of typical FTF waste solids are appreciably higher than those of typical HTF waste solids. Other constituents present at significantly higher concentrations in the typical FTF waste solids include uranium, nickel, ruthenium, zinc, silver, cobalt and copper. In contrast, constituents present at significantly higher concentrations in the typical HTF waste solids …
Date: August 29, 2012
Creator: Reboul, S.
Object Type: Report
System: The UNT Digital Library
Energy Conservation Tests of a Coupled Kinetic-kinetic Plasma-neutral Transport Code (open access)

Energy Conservation Tests of a Coupled Kinetic-kinetic Plasma-neutral Transport Code

A Monte Carlo neutral transport routine, based on DEGAS2, has been coupled to the guiding center ion-electron-neutral neoclassical PIC code XGC0 to provide a realistic treatment of neutral atoms and molecules in the tokamak edge plasma. The DEGAS2 routine allows detailed atomic physics and plasma-material interaction processes to be incorporated into these simulations. The spatial pro le of the neutral particle source used in the DEGAS2 routine is determined from the uxes of XGC0 ions to the material surfaces. The kinetic-kinetic plasma-neutral transport capability is demonstrated with example pedestal fueling simulations.
Date: August 29, 2012
Creator: D.P. Stotler, C.S. Chang, S.H. Ku, J. Lang and G. Park
Object Type: Report
System: The UNT Digital Library
Inertial Confinement Fusion and the National Ignition Facility (NIF) (open access)

Inertial Confinement Fusion and the National Ignition Facility (NIF)

Inertial confinement fusion (ICF) seeks to provide sustainable fusion energy by compressing frozen deuterium and tritium fuel to extremely high densities. The advantages of fusion vs. fission are discussed, including total energy per reaction and energy per nucleon. The Lawson Criterion, defining the requirements for ignition, is derived and explained. Different confinement methods and their implications are discussed. The feasibility of creating a power plant using ICF is analyzed using realistic and feasible numbers. The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory is shown as a significant step forward toward making a fusion power plant based on ICF. NIF is the world’s largest laser, delivering 1.8 MJ of energy, with a peak power greater than 500 TW. NIF is actively striving toward the goal of fusion energy. Other uses for NIF are discussed.
Date: August 29, 2012
Creator: Ross, P.
Object Type: Article
System: The UNT Digital Library
Pedestal Fueling Simulations with a Coupled Kinetic-kinetic Plasma-neutral Transport Code (open access)

Pedestal Fueling Simulations with a Coupled Kinetic-kinetic Plasma-neutral Transport Code

A Monte Carlo neutral transport routine, based on DEGAS2, has been coupled to the guiding center ion-electron-neutral neoclassical PIC code XGC0 to provide a realistic treatment of neutral atoms and molecules in the tokamak edge plasma. The DEGAS2 routine allows detailed atomic physics and plasma-material interaction processes to be incorporated into these simulations. The spatial pro le of the neutral particle source used in the DEGAS2 routine is determined from the uxes of XGC0 ions to the material surfaces. The kinetic-kinetic plasma-neutral transport capability is demonstrated with example pedestal fueling simulations.
Date: August 29, 2012
Creator: D.P. Stotler, C.S. Chang, S.H. Ku, J. Lang and G.Y. Park
Object Type: Article
System: The UNT Digital Library
Thermal Analysis to Calculate the Vessel Temperature and Stress in Alcator C-Mod Due to the Divertor Upgrade (open access)

Thermal Analysis to Calculate the Vessel Temperature and Stress in Alcator C-Mod Due to the Divertor Upgrade

Alcator C-Mod is planning an upgrade to its outer divertor. The upgrade is intended to correct the existing outer divertor alignment with the plasma, and to operate at elevated temperatures. Higher temperature operation will allow study of edge physics behavior at reactor relevant temperatures. The outer divertor and tiles will be capable of operating at 600oC. Longer pulse length, together with the plasma and RF heat of 9MW, and the inclusion of heater elements within the outer divertor produces radiative energy which makes the sustained operation much more difficult than before. An ANSYS model based on ref. 1 was built for the global thermal analysis of C-Mod. It models the radiative surfaces inside the vessel and between the components, and also includes plasma energy deposition. Different geometries have been simulated and compared. Results show that steady state operation with the divertor at 600oC is possible with no damage to major vessel internal components. The differential temperature between inner divertor structure, or "girdle" and inner vessel wall is ~70oC. This differential temperature is limited by the capacity of the studs that hold the inner divertor backing plates to the vessel wall. At a 70oC temperature differential the stress on the studs …
Date: August 29, 2012
Creator: Han Zhang, Peter H. Titus, Robert Ellis, Soren Harrison and Rui Vieira
Object Type: Article
System: The UNT Digital Library
The use Na, Li, K cations for modification of ZSM-5 zewolite to control hydrocarbon cold-start emission (open access)

The use Na, Li, K cations for modification of ZSM-5 zewolite to control hydrocarbon cold-start emission

This paper addresses the problem of controlling hydrocarbon emissions from cold-start of engines by investigating the adsorbents which could adsorb the hydrocarbons at cold temperatures and hold them to 250-300 ?. The materials, that has been studied, are based on the modification of ZSM-5 (SiO{sub 2}/Al{sub 2}O{sub 3} = 35) zeolite with Li, K, Na cations. It has been shown that the introduction of Li, Na and K in an amount that is equivalent to the content of Al in zeolite results in occurrence of toluene temperature desorption peaks at high-temperatures. The toluene temperature desorption curves for 5%Li-ZSM-5 and 2.3%Na-ZSM-5 zeolites are identical and have peak toluene desorption rate between 200 to 400 ?. Upon analysis of toluene adsorption isotherms for 2.3%Na-ZSM-5 and 5%Li-ZSM-5, it was concluded that the toluene diffusion inside of the modified zeolites channels is extremely slow and the sorption capacity of 2.3%Na-ZSM-5 is higher than with 5%Li-ZSM-5. The 2.3%Na-ZSM-5 didn't change toluene temperature programmed desorption (TPD) rate of curve after the treatment in environment with 10% ?{sub 2}? at 750-800 ? for about 28 h. The 2.3%Na-ZSM-5 zeolite is very promising as adsorbent to control the cold-start hydrocarbon emissions.
Date: August 29, 2012
Creator: V., Golubeva; U., Rohatgi; Korableva, A.; Anischenko, O.; Kustov, L.; Nissenbaum, V et al.
Object Type: Article
System: The UNT Digital Library
Verification survey report of the south waste tank farm training/test tower and hazardous waste storage lockers at the West Valley demonstration project, West Valley, New York (open access)

Verification survey report of the south waste tank farm training/test tower and hazardous waste storage lockers at the West Valley demonstration project, West Valley, New York

A team from ORAU's Independent Environmental Assessment and Verification Program performed verification survey activities on the South Test Tower and four Hazardous Waste Storage Lockers. Scan data collected by ORAU determined that both the alpha and alpha-plus-beta activity was representative of radiological background conditions. The count rate distribution showed no outliers that would be indicative of alpha or alpha-plus-beta count rates in excess of background. It is the opinion of ORAU that independent verification data collected support the site?s conclusions that the South Tower and Lockers sufficiently meet the site criteria for release to recycle and reuse.
Date: August 29, 2012
Creator: Weaver, Phyllis C.
Object Type: Report
System: The UNT Digital Library
DEPOSITION TANK CORROSION TESTING FOR ENHANCED CHEMICAL CLEANING POST OXALIC ACID DESTRUCTION (open access)

DEPOSITION TANK CORROSION TESTING FOR ENHANCED CHEMICAL CLEANING POST OXALIC ACID DESTRUCTION

An Enhanced Chemical Cleaning (ECC) process is being developed to aid in the high level waste tank closure at the Savannah River Site. The ECC process uses an advanced oxidation process (AOP) to destroy the oxalic acid that is used to remove residual sludge from a waste tank prior to closure. The AOP process treats the dissolved sludge with ozone to decompose the oxalic acid through reactions with hydroxyl radicals. The effluent from this oxalic acid decomposition is to be sent to a Type III waste tank and may be corrosive to these tanks. As part of the hazardous simulant testing that was conducted at the ECC vendor location, corrosion testing was conducted to determine the general corrosion rate for the deposition tank and to assess the susceptibility to localized corrosion, especially pitting. Both of these factors impact the calculation of hydrogen gas generation and the structural integrity of the tanks, which are considered safety class functions. The testing consisted of immersion and electrochemical testing of A537 carbon steel, the material of construction of Type III tanks, and 304L stainless steel, the material of construction for transfer piping. Tests were conducted in solutions removed from the destruction loop of the …
Date: August 29, 2011
Creator: Mickalonis, J.
Object Type: Report
System: The UNT Digital Library
Diagnosing Implosions at the National Ignition Facility with X-ray Spectroscopy (open access)

Diagnosing Implosions at the National Ignition Facility with X-ray Spectroscopy

None
Date: August 29, 2011
Creator: Regan, S. P.; Epstein, R.; Hammel, B. A.; Suter, L. J.; Ralph, J.; Scott, H. et al.
Object Type: Article
System: The UNT Digital Library
Energy Renovations: Volume 14: HVAC - A Guide for Contractors to Share with Homeowners (open access)

Energy Renovations: Volume 14: HVAC - A Guide for Contractors to Share with Homeowners

This report was prepared by PNNL for DOE's Building America program and is intended as a guide that energy performance contractors can share with homeowners to describe various energy-efficient options for heating, cooling, and ventilating existing homes. The report provides descriptions of many common and not-so-common HVAC systems, including their advantages and disadvantages, efficiency ranges and characteristics of high-performance models, typical costs, and climate considerations. The report also provides decision trees and tables of useful information for homeowners who are making decisions about adding, replacing, or upgrading existing HVAC equipment in their homes. Information regarding home energy performance assessments (audits) and combustion safety issues when replacing HVAC equipment are also provided.
Date: August 29, 2011
Creator: Gilbride, Theresa L.; Baechler, Michael C.; Hefty, Marye G.; Hand, James R. & Love, Pat M.
Object Type: Report
System: The UNT Digital Library
FINAL REPORT – CHARACTERIZATION SURVEY OF THE SPRU LOWER LEVEL HILLSIDE AREA AT THE KNOLLS ATOMIC POWER LABORATORY, NISKAYUNA, NEW YORK DCN 5146-SR-01-0 (open access)

FINAL REPORT – CHARACTERIZATION SURVEY OF THE SPRU LOWER LEVEL HILLSIDE AREA AT THE KNOLLS ATOMIC POWER LABORATORY, NISKAYUNA, NEW YORK DCN 5146-SR-01-0

The Separations Process Research Unit (SPRU) is located within the boundary of Knolls Atomic Power Laboratory (KAPL) at 2425 River Road, Niskayuna, Schenectady County, New York (Figure A-1). SPRU was designed and developed to research an efficient process to chemically separate plutonium and uranium from processed fuel. Buildings H2 and G2 were the primary research and process facilities. SPRU operated between February 1950 and October 1953 at which time the research was successful in developing useable reduction oxidation and plutonium uranium extraction processes. These processes were subsequently moved to the Hanford and the Savannah River sites for full-scale operations. Building H2 was used by KAPL after the SPRU process ceased until the late 1990s for radioactive wastewater processing and Building G2 was utilized for offices. Process areas and equipment were maintained in a safe condition under a surveillance and maintenance program.
Date: August 29, 2011
Creator: Harpenau, Evan
Object Type: Report
System: The UNT Digital Library
Gyrokinetic Equations For Strong-Gradient Regions (open access)

Gyrokinetic Equations For Strong-Gradient Regions

None
Date: August 29, 2011
Creator: Dimits, A M
Object Type: Article
System: The UNT Digital Library
New Discoveries Bring us Closer to a Predictive Theory of Fission (open access)

New Discoveries Bring us Closer to a Predictive Theory of Fission

None
Date: August 29, 2011
Creator: Younes, W
Object Type: Report
System: The UNT Digital Library
TESTING OF THE DUAL ROTARY FILTER SYSTEM (open access)

TESTING OF THE DUAL ROTARY FILTER SYSTEM

The Savannah River National Laboratory (SRNL) installed and tested two hydraulically connected SpinTek rotary microfilter (RMF) units to determine the behavior of a multiple filter system. Both units were successfully controlled by a control scheme written in DELTA-V architecture by Savannah River Remediation (SRR) Process Control Engineering personnel. The control system was tuned to provide satisfactory response to changing conditions during the operation of the multi-filter system. Stability was maintained through the startup and shutdown of one of the filter units while the second was still in operation. The installation configuration originally proposed by the Small Colum Ion Exchange (SCIX) project of independent filter and motor mountings may be susceptible to vibration. Significant stiffening of the filter and motor mounts was required to minimize the vibration. Alignment of the motor to the filter was a challenge in this test configuration. The deployment configuration must be easy to manipulate and allow for fine adjustment. An analysis of the vibration signature of the test system identified critical speeds. Whether it corresponds to the resonance frequency of a rotor radial vibration mode that was excited by rotor unbalance is uncertain based upon the measurements. A relative motion series should be completed on the …
Date: August 29, 2011
Creator: Herman, D.; Fowley, M. & Stefanko, D.
Object Type: Report
System: The UNT Digital Library
TREATMENT TANK OFF-GAS TESTING FOR THE ENHANCED CHEMICAL CLEANING PROCESS (open access)

TREATMENT TANK OFF-GAS TESTING FOR THE ENHANCED CHEMICAL CLEANING PROCESS

The purpose of this activity was to provide a bounding estimate of the volume of hydrogen gas generated during Enhanced Chemical Cleaning (ECC) of residual sludge remaining in a Type I or Type II treatment tank as well as to provide results independent of the sludge volume in the waste tank to be cleaned. Previous testing to support Chemical Cleaning was based on a 20:1 oxalic acid to sludge ratio. Hydrogen gas evolution is the primary safety concern. Sealed vessel coupon tests were performed to estimate the hydrogen generation rate due to corrosion of carbon steel by 2.5 wt.% oxalic acid. These tests determined the maximum instantaneous hydrogen generation rate, the rate at which the generation rate decays, and the total hydrogen generated. These values were quantified based on a small scale methodology similar to the one described in WSRC-STI-2007-00209, Rev. 0. The measured rates support identified Safety Class functions. The tests were performed with ASTM A285 Grade C carbon steel coupons. Bounding conditions were determined for the solution environment. The oxalic acid concentration was 2.5 wt.% and the test temperature was 75 C. The test solution was agitated and contained no sludge simulant. Duplicate tests were performed and showed …
Date: August 29, 2011
Creator: Wiersma, B.
Object Type: Report
System: The UNT Digital Library
VERIFICATION OF THE DEFENSE WASTE PROCESSING FACILITY'S (DWPF) PROCESS DIGESTION METHOD FOR THE SLUDGE BATCH 7B BLEND SAMPLE (open access)

VERIFICATION OF THE DEFENSE WASTE PROCESSING FACILITY'S (DWPF) PROCESS DIGESTION METHOD FOR THE SLUDGE BATCH 7B BLEND SAMPLE

None
Date: August 29, 2011
Creator: Click, D.; Edwards, T. & Wiedenman, B.
Object Type: Report
System: The UNT Digital Library
Designing small catalysts for CO2 capture (open access)

Designing small catalysts for CO2 capture

None
Date: August 29, 2010
Creator: Wong, S. E.; Lau, E. Y.; Satcher, J. H.; Aines, R. D. & Lightstone, F. C.
Object Type: Article
System: The UNT Digital Library