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ACTUAL-WASTE TESTS OF ENHANCED CHEMICAL CLEANING FOR RETRIEVAL OF SRS HLW SLUDGE TANK HEELS AND DECOMPOSITION OF OXALIC ACID (open access)

ACTUAL-WASTE TESTS OF ENHANCED CHEMICAL CLEANING FOR RETRIEVAL OF SRS HLW SLUDGE TANK HEELS AND DECOMPOSITION OF OXALIC ACID

Savannah River National Laboratory conducted a series of tests on the Enhanced Chemical Cleaning (ECC) process using actual Savannah River Site waste material from Tanks 5F and 12H. Testing involved sludge dissolution with 2 wt% oxalic acid, the decomposition of the oxalates by ozonolysis (with and without the aid of ultraviolet light), the evaporation of water from the product, and tracking the concentrations of key components throughout the process. During ECC actual waste testing, the process was successful in decomposing oxalate to below the target levels without causing substantial physical or chemical changes in the product sludge.
Date: January 12, 2012
Creator: Martino, C.; King, W. & Ketusky, E.
System: The UNT Digital Library
BIO-MONITORING FOR URANIUM USING STREAM-SIDE TERRESTRIAL PLANTS AND MACROPHYTES (open access)

BIO-MONITORING FOR URANIUM USING STREAM-SIDE TERRESTRIAL PLANTS AND MACROPHYTES

This study evaluated the abilities of various plant species to act as bio-monitors for environmental uranium (U) contamination. Vegetation and soil samples were collected from a U processing facility. The water-way fed from facility storm and processing effluents was the focal sample site as it represented a primary U transport mechanism. Soils and sediments from areas exposed to contamination possessed U concentrations that averaged 630 mg U kg{sup -1}. Aquatic mosses proved to be exceptional accumulators of U with dry weight (dw) concentrations measuring as high as 12500 mg U kg{sup -1} (approximately 1% of the dw mass was attributable to U). The macrophytes (Phragmites communis, Scripus fontinalis and Sagittaria latifolia) were also effective accumulators of U. In general, plant roots possessed higher concentrations of U than associated upper portions of plants. For terrestrial plants, the roots of Impatiens capensis had the highest observed levels of U accumulation (1030 mg kg{sup -1}), followed by the roots of Cyperus esculentus and Solidago speciosa. The concentration ratio (CR) characterized dry weight (dw) vegetative U levels relative to that in associated dw soil. The plant species that accumulated U at levels in excess of that found in the soil were: P. communis root …
Date: January 12, 2012
Creator: Caldwell, E.; Duff, M.; Hicks, T.; Coughlin, D.; Hicks, R. & Dixon, E.
System: The UNT Digital Library
THE EFFECT OF THE PRESENCE OF OZONE ON THE LOWER FLAMMABILITY LIMIT OF HYDROGEN IN VESSELS CONTAINING SAVANNAH RIVER SITE HIGH LEVEL WASTE (open access)

THE EFFECT OF THE PRESENCE OF OZONE ON THE LOWER FLAMMABILITY LIMIT OF HYDROGEN IN VESSELS CONTAINING SAVANNAH RIVER SITE HIGH LEVEL WASTE

The Enhanced Chemical Cleaning (ECC) process uses ozone to effect the oxidation of metal oxalates produced during the dissolution of sludge in the Savannah River Site (SRS) waste tanks. The ozone reacts with the metal oxalates to form metal oxide and hydroxide precipitants, and the CO{sub 2}, O{sub 2}, H{sub 2}O and any unreacted O{sub 3} gases are discharged into the vapor space. In addition to the non-radioactive metals in the waste, however, the SRS radioactive waste also contains a variety of radionuclides, hence, hydrogen gas is also present in the vapor space of the ECC system. Because hydrogen is flammable, the impact of this resultant gas stream on the Lower Flammability Limit (LFL) of hydrogen must be understood for all possible operating scenarios of both normal and off-normal situations, with particular emphasis at the elevated temperatures and pressures of the typical ECC operating conditions. Oxygen is a known accelerant in combustion reactions, but while there are data associated with the behavior of hydrogen/oxygen environments, recent, relevant studies addressing the effect of ozone on the flammability limit of hydrogen proved scarce. Further, discussions with industry experts verified the absence of data in this area and indicated that laboratory testing, specific …
Date: January 12, 2012
Creator: Sherburne, C.
System: The UNT Digital Library
HANFORD SITE SUSTAINABILITY PROGRAM RICHLAND WASHINGTON - 12464 (open access)

HANFORD SITE SUSTAINABILITY PROGRAM RICHLAND WASHINGTON - 12464

In support of implementation of Executive Order (EO) 13514, Federal Leadership in Environmental, Energy and Economic Performance, the Hanford Site Sustainability Plan was developed to implement strategies and activities required to achieve the prescribed goals in the EO as well as demonstrate measurable progress in environmental stewardship at the Hanford Site. The Hanford Site Sustainability Program was developed to demonstrate progress towards sustainability goals as defined and established in Executive Order (EO) 13514, Federal Leadership in Environmental, Energy and Economic Performance; EO 13423, Strengthening Federal Environmental, Energy and Transportation Management, and several applicable Energy Acts. Multiple initiatives were undertaken in Fiscal Year (FY) 2011 to implement the Program and poise the Hanford Site as a leader in environmental stewardship. In order to implement the Hanford Site Sustainability Program, a Sustainability Plan was developed in conjunction with prime contractors, two U.S. Department of Energy (DOE) Offices, and key stakeholders to serve as the framework for measuring progress towards sustainability goals. Based on the review of these metrics and future plans, several activities were initiated to proactively improve performance or provide alternatives for future consideration contingent on available funding. A review of the key metric associated with energy consumption for the Hanford …
Date: January 12, 2012
Creator: LL, FRITZ
System: The UNT Digital Library
Livermore Computer Network Simulation Program (open access)

Livermore Computer Network Simulation Program

None
Date: January 12, 2012
Creator: Barnes, P. D.; Brase, J. M.; Canales, T. W.; Damante, M. M.; Horsley, M. A.; Jefferson, D. R. et al.
System: The UNT Digital Library
Radioactive Demonstrations of Fluidized Bed Steam Reforming With Acutal Hanford Low Activity Wastes Verifying Fbsr as a Supplementary Treatment (open access)

Radioactive Demonstrations of Fluidized Bed Steam Reforming With Acutal Hanford Low Activity Wastes Verifying Fbsr as a Supplementary Treatment

The U.S. Department of Energy's Office of River Protection is responsible for the retrieval, treatment, immobilization, and disposal of Hanford's tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level waste (HLW) and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the cleanup mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA). Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. Fluidized Bed Steam Reforming (FBSR) is one of the supplementary treatments being considered. FBSR offers a moderate temperature (700-750 C) continuous method by which LAW and other secondary wastes can be processed irrespective of whether they contain organics, nitrates/nitrites, sulfates/sulfides, chlorides, fluorides, and/or radio-nuclides like I-129 and Tc-99. Radioactive testing of Savannah River LAW (Tank 50) …
Date: January 12, 2012
Creator: Jantzen, Carol M.; Crawford, C. L.; Burket, P. R.; Bannochie, C. J.; Daniel, W. G.; Nash, C. A. et al.
System: The UNT Digital Library
SLUDGE HEEL REMOVAL BY ALUMINUM DISSOLUTION AT SAVANNAH RIVER SITE 12390 (open access)

SLUDGE HEEL REMOVAL BY ALUMINUM DISSOLUTION AT SAVANNAH RIVER SITE 12390

High Level Waste (HLW) at the Savannah River Site (SRS) is currently stored in aging underground storage tanks. This waste is a complex mixture of insoluble solids, referred to as sludge, and soluble salts. Continued long-term storage of these radioactive wastes poses an environmental risk. Operations are underway to remove and disposition the waste, clean the tanks and fill with grout for permanent closure. Heel removal is the intermediate phase of the waste retrieval and tank cleaning process at SRS, which is intended to reduce the volume of waste prior to treatment with oxalic acid. The goal of heel removal is to reduce the residual amount of radioactive sludge wastes to less than 37,900 liters (10,000 gallons) of wet solids. Reducing the quantity of residual waste solids in the tank prior to acid cleaning reduces the amount of acid required and reduces the amount of excess acid that could impact ongoing waste management processes. Mechanical heel removal campaigns in Tank 12 have relied solely on the use of mixing pumps that have not been effective at reducing the volume of remaining solids. The remaining waste in Tank 12 is known to have a high aluminum concentration. Aluminum dissolution by caustic …
Date: January 12, 2012
Creator: Keefer, M.
System: The UNT Digital Library
Statistical Evaluation of Small Scale Mixing Demonstration Sampling and Batch Transfer Performance - 12093 (open access)

Statistical Evaluation of Small Scale Mixing Demonstration Sampling and Batch Transfer Performance - 12093

The ability to effectively mix, sample, certify, and deliver consistent batches of High Level Waste (HLW) feed from the Hanford Double Shell Tanks (DST) to the Waste Treatment and Immobilization Plant (WTP) presents a significant mission risk with potential to impact mission length and the quantity of HLW glass produced. DOE's Tank Operations Contractor, Washington River Protection Solutions (WRPS) has previously presented the results of mixing performance in two different sizes of small scale DSTs to support scale up estimates of full scale DST mixing performance. Currently, sufficient sampling of DSTs is one of the largest programmatic risks that could prevent timely delivery of high level waste to the WTP. WRPS has performed small scale mixing and sampling demonstrations to study the ability to sufficiently sample the tanks. The statistical evaluation of the demonstration results which lead to the conclusion that the two scales of small DST are behaving similarly and that full scale performance is predictable will be presented. This work is essential to reduce the risk of requiring a new dedicated feed sampling facility and will guide future optimization work to ensure the waste feed delivery mission will be accomplished successfully. This paper will focus on the analytical …
Date: January 12, 2012
Creator: Greer, D. A. & Thien, M. G.
System: The UNT Digital Library
Ab Initio Calculations Of Light-Ion Reactions (open access)

Ab Initio Calculations Of Light-Ion Reactions

The exact treatment of nuclei starting from the constituent nucleons and the fundamental interactions among them has been a long-standing goal in nuclear physics. In addition to the complex nature of nuclear forces, one faces the quantum-mechanical many-nucleon problem governed by an interplay between bound and continuum states. In recent years, significant progress has been made in ab initio nuclear structure and reaction calculations based on input from QCD employing Hamiltonians constructed within chiral effective field theory. In this contribution, we present one of such promising techniques capable of describing simultaneously both bound and scattering states in light nuclei. By combining the resonating-group method (RGM) with the ab initio no-core shell model (NCSM), we complement a microscopic cluster approach with the use of realistic interactions and a microscopic and consistent description of the clusters. We discuss applications to light nuclei scattering, radiative capture and fusion reactions.
Date: March 12, 2012
Creator: Navratil, P; Quaglioni, S; Roth, R & Horiuchi, W
System: The UNT Digital Library
Confinement Contains Condensates (open access)

Confinement Contains Condensates

Dynamical chiral symmetry breaking and its connection to the generation of hadron masses has historically been viewed as a vacuum phenomenon. We argue that confinement makes such a position untenable. If quark-hadron duality is a reality in QCD, then condensates, those quantities that have commonly been viewed as constant empirical mass-scales that fill all spacetime, are instead wholly contained within hadrons; i.e., they are a property of hadrons themselves and expressed, e.g., in their Bethe-Salpeter or light-front wave functions. We explain that this paradigm is consistent with empirical evidence, and incidentally expose misconceptions in a recent Comment.
Date: March 12, 2012
Creator: Brodsky, Stanley J.; Roberts, Craig D.; Shrock, Robert & Tandy, Peter C.
System: The UNT Digital Library
Determination of free CO2 in emergent groundwaters using a commercial beverage carbonation meter (open access)

Determination of free CO2 in emergent groundwaters using a commercial beverage carbonation meter

Dissolved CO{sub 2} in groundwater is frequently supersaturated relative to its equilibrium with atmospheric partial pressure and will degas when it is conveyed to the surface. Estimates of dissolved CO{sub 2} concentrations can vary widely between different hydrochemical facies because they have different sources of error (e.g., rapid degassing, low alkalinity, non-carbonate alkalinity). We sampled 60 natural spring and mine waters using a beverage industry carbonation meter, which measures dissolved CO{sub 2} based on temperature and pressure changes as the sample volume is expanded. Using a modified field protocol, the meter was found to be highly accurate in the range 0.2–35 mMCO{sub 2}. The meter provided rapid, accurate and precise measurements of dissolved CO{sub 2} in natural waters for a range of hydrochemical facies. Dissolved CO{sub 2} concentrations measured in the field with the carbonation meter were similar to CO{sub 2} determined using the pH-alkalinity approach, but provided immediate results and avoided errors from alkalinity and pH determination. The portability and ease of use of the carbonation meter in the field made it well-suited to sampling in difficult terrain. The carbonation meter has proven useful in the study of aquatic systems where CO{sub 2} degassing drives geochemical changes that result …
Date: March 12, 2012
Creator: Vesper, Dorothy J. & Edenborn, Harry M.
System: The UNT Digital Library
Evaluation of the RDP Classifier Accuracy Using 16S rRNA Gene Variable Regions (open access)

Evaluation of the RDP Classifier Accuracy Using 16S rRNA Gene Variable Regions

This article uses full-length 16S rRNA gene alignments from the SILVA database to simulate the PCR products of the combined variable regions.
Date: March 12, 2012
Creator: Vilo, Claudia A. & Dong, Qunfeng
System: The UNT Digital Library
Final Version: Orbital Specificity in the Unoccupied States of UO2 from Resonant Inverse Photoelectron Spectroscopy (open access)

Final Version: Orbital Specificity in the Unoccupied States of UO2 from Resonant Inverse Photoelectron Spectroscopy

One of the crucial questions of all actinide electronic structure determinations is the issue of 5f versus 6d character and the distribution of these components across the density of states. Here, a break-though experiment is discussed, which has allowed the direct determination of the U5f and U6d contributions to the unoccupied density of states (UDOS) in Uranium Dioxide. A novel Resonant Inverse Photoelectron (RIPES) and X-ray Emission Spectroscopy (XES) investigation of UO{sub 2} is presented. It is shown that the U5f and U6d components are isolated and identified unambiguously.
Date: March 12, 2012
Creator: Tobin, J G & Yu, S W
System: The UNT Digital Library
The NETL Aqueous Process: Recent Developments and Novel Applications (open access)

The NETL Aqueous Process: Recent Developments and Novel Applications

None
Date: March 12, 2012
Creator: O'Connor, W.K.; Rush, G.E. & Verba, C.A.
System: The UNT Digital Library
Snowflake divertor configuration studies in NSTX. (open access)

Snowflake divertor configuration studies in NSTX.

None
Date: March 12, 2012
Creator: Soukhanovskii, V A
System: The UNT Digital Library
TECA: A Parallel Toolkit for Extreme Climate Analysis (open access)

TECA: A Parallel Toolkit for Extreme Climate Analysis

We present TECA, a parallel toolkit for detecting extreme events in large climate datasets. Modern climate datasets expose parallelism across a number of dimensions: spatial locations, timesteps and ensemble members. We design TECA to exploit these modes of parallelism and demonstrate a prototype implementation for detecting and tracking three classes of extreme events: tropical cyclones, extra-tropical cyclones and atmospheric rivers. We process a modern TB-sized CAM5 simulation dataset with TECA, and demonstrate good runtime performance for the three case studies.
Date: March 12, 2012
Creator: Prabhat, Mr; Ruebel, Oliver; Byna, Surendra; Wu, Kesheng; Li, Fuyu; Wehner, Michael et al.
System: The UNT Digital Library
Ursolic Acid Inhibits the Initiation, Progression of Prostate Cancer and Prolongs the Survival of TRAMP Mice by Modulating Pro-Inflammatory Pathways (open access)

Ursolic Acid Inhibits the Initiation, Progression of Prostate Cancer and Prolongs the Survival of TRAMP Mice by Modulating Pro-Inflammatory Pathways

Article on ursolic acid inhibiting the initiation, progression of prostate cancer and prolonging the survival of TRAMP mice by modulating pro-inflammatory pathways.
Date: March 12, 2012
Creator: Shanmugam, Muthu K.; Ong, Tina H.; Kumar, Alan Prem; Chang, Kai Lun; Ho, Paul C.; Wong, Peter T. H. et al.
System: The UNT Digital Library
The assumption of a reliable instrument and other pitfalls to avoid when considering the reliability of data (open access)

The assumption of a reliable instrument and other pitfalls to avoid when considering the reliability of data

This article helps researchers avoid common pitfalls associated with reliability including incorrectly assuming that measurement error always attenuates observed score correlations, different sources of measurement error originate from the same source, and reliability is a function of instrumentation.
Date: April 12, 2012
Creator: Nimon, Kim F.; Zientek, Linda Reichwein & Henson, Robin K.
System: The UNT Digital Library
On-Chip Dielectrophoretic Separation and Concentration of Viable, Non-Viable and Viable but Not Culturable (VBNC) Escherichia coli (open access)

On-Chip Dielectrophoretic Separation and Concentration of Viable, Non-Viable and Viable but Not Culturable (VBNC) Escherichia coli

Although bacterial culture remains the gold standard for detection of viable bacteria in environmental specimens, the typical time requirement of twenty-four hours can delay and even jeopardize appropriate public health intervention. In addition, culture is incapable of detecting viable but not culturable (VBNC) species. Conversely, nucleic acid and antibody-based methods greatly decrease time to detection but rarely characterize viability of the bacteria detected. Through selection by membrane permeability, the method described in this work employs positive dielectrophoresis (pDEP) for separation and purification of viable and VBNC species from water and allows concentration of bacteria for downstream applications.
Date: April 12, 2012
Creator: Packard, M M; Shusteff, M & Alocilja, E C
System: The UNT Digital Library
Sexual Misconduct with Congregants or Parishioners: Crafting a Model Statute (open access)

Sexual Misconduct with Congregants or Parishioners: Crafting a Model Statute

Article discussing sexual misconduct with congregants or parishioners and crafting a model statute.
Date: April 12, 2012
Creator: Toben, Bradley J. B. & Helge, Kris
System: The UNT Digital Library
Boosted Objects: A Probe of Beyond the Standard Model Physics (open access)

Boosted Objects: A Probe of Beyond the Standard Model Physics

We present the report of the hadronic working group of the BOOST2010 workshop held at the University of Oxford in June 2010. The first part contains a review of the potential of hadronic decays of highly boosted particles as an aid for discovery at the LHC and a discussion of the status of tools developed to meet the challenge of reconstructing and isolating these topologies. In the second part, we present new results comparing the performance of jet grooming techniques and top tagging algorithms on a common set of benchmark channels. We also study the sensitivity of jet substructure observables to the uncertainties in Monte Carlo predictions.
Date: June 12, 2012
Creator: Abdesselam, A.; U., /Oxford; Kuutmann, E.Bergeaas; /DESY; Bitenc, U.; U., /Freiburg et al.
System: The UNT Digital Library
Detection of a Spectral Break in the Extra Hard Component of GRB 090926A (open access)

Detection of a Spectral Break in the Extra Hard Component of GRB 090926A

None
Date: June 12, 2012
Creator: Ackermann, M.; Ajello, M.; Asano, K.; Axelsson, M.; Baldini, L.; Ballet, J. et al.
System: The UNT Digital Library
Experimental Characterization of Space Charge in IZIP Detectors (open access)

Experimental Characterization of Space Charge in IZIP Detectors

Interleaved ionization electrode geometries offer the possibility of efficient rejection of near-surface events. The CDMS collaboration has recently implemented this interleaved approach for the charge and phonon readout for our germanium detectors. During a recent engineering run, the detectors were found to lose ionization stability quickly. This paper summarizes studies done in order to determine the underlying cause of the instability, as well as possible running modes that maintain stability without unacceptable loss of livetime. Additionally, results are shown for the new version IZIP mask which attempts to improve the overall stability of the detectors.
Date: June 12, 2012
Creator: Doughty, T; /UC, Berkeley; Pyle, M.; U., /Stanford; Mirabolfathi, N.; Serfass, B. et al.
System: The UNT Digital Library
FREYA-a new Monte Carlo code for improved modeling of fission chains (open access)

FREYA-a new Monte Carlo code for improved modeling of fission chains

A new simulation capability for modeling of individual fission events and chains and the transport of fission products in materials is presented. FREYA ( Fission Yield Event Yield Algorithm ) is a Monte Carlo code for generating fission events providing correlated kinematic information for prompt neutrons, gammas, and fragments. As a standalone code, FREYA calculates quantities such as multiplicity-energy, angular, and gamma-neutron energy sharing correlations. To study materials with multiplication, shielding effects, and detectors, we have integrated FREYA into the general purpose Monte Carlo code MCNP. This new tool will allow more accurate modeling of detector responses including correlations and the development of SNM detectors with increased sensitivity.
Date: June 12, 2012
Creator: Hagmann, C A; Randrup, J & Vogt, R L
System: The UNT Digital Library