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Synthesis, characterization, phase diagrams and superconducting and normal state magnetic properties of La{sub 2{minus}x}Sr{sub x}CuO{sub 4} (0 {le} x {le} 0.08) and electrochemically oxidized La{sub 2{minus}x}Sr{sub x}CuO{sub 4+{delta}} (0 {le} x {le} 0.33, 0 {le} {delta} {le} 0.12) (open access)

Synthesis, characterization, phase diagrams and superconducting and normal state magnetic properties of La{sub 2{minus}x}Sr{sub x}CuO{sub 4} (0 {le} x {le} 0.08) and electrochemically oxidized La{sub 2{minus}x}Sr{sub x}CuO{sub 4+{delta}} (0 {le} x {le} 0.33, 0 {le} {delta} {le} 0.12)

La{sub 2{minus}x}Sr{sub x}CuO{sub 4} (0 {le} x {le} 0.15) can all be intercalated with oxygen by a novel electrochemical oxidation method. Bulk superconductivity is found with an onset {Tc} {approx} 40 K for the whole range 0.01 {le} x {le} 0.15; for x = 0.25 and 0.33, the electrochemical oxidation did not improve the superconducting properties. The magnetic susceptibility {chi}(T = 50--320 K) data for La{sub 2}CuO{sub 4.11} and La{sub 1.92}Sr{sub 0.08}CuO{sub 4.07} are nearly identical with those of conventionally prepared La{sub 1.85}Sr{sub 0.15}CuO{sub 4}, indicating that the hole doping level (p) in the CuO{sub 2} planes of the three compounds is nearly the same. Combined thermogravimetric analysis and iodometric titration experiments indicate that part of the intercalated oxygen has a formal valence close to {minus}1. The maximum doped-hole concentration in the CuO{sub 2} planes that can be achieved from combined Sr-doping and electrochemical oxygen doping for 0 {le} x {le} 0.15 is p {approx} 0.16 holes/formula unit. Oxygen can also intercalate into single crystal La{sub 2}CuO{sub 4} through a slow electrochemical oxidation process. The required low current and long time for the charging process reflects that the oxygen intercalation for a single crystal is limited by its small specific …
Date: August 1, 1993
Creator: Chou, F.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
1993 RCRA Part B permit renewal application, Savannah River Site: Volume 10, Consolidated Incineration Facility, Section C, Revision 1 (open access)

1993 RCRA Part B permit renewal application, Savannah River Site: Volume 10, Consolidated Incineration Facility, Section C, Revision 1

This section describes the chemical and physical nature of the RCRA regulated hazardous wastes to be handled, stored, and incinerated at the Consolidated Incineration Facility (CIF) at the Savannah River Site. It is in accordance with requirements of South Carolina Hazardous Waste Management Regulations R.61-79.264.13(a) and(b), and 270.14(b)(2). This application is for permit to store and teat these hazardous wastes as required for the operation of CIF. The permit is to cover the storage of hazardous waste in containers and of waste in six hazardous waste storage tanks. Treatment processes include incineration, solidification of ash, and neutralization of scrubber blowdown.
Date: August 1, 1993
Creator: Molen, G.
Object Type: Report
System: The UNT Digital Library
The Si(100)-Sb 2{times}1 and Ge(100) 2{times}1 surfaces: A multi-technique study (open access)

The Si(100)-Sb 2{times}1 and Ge(100) 2{times}1 surfaces: A multi-technique study

The electronic and geometric structures of the clean and Sb terminated Si(100)2{times}1 and Ge(100)-2{times}1 surfaces have been investigated using a multi-technique approach. Low energy electron diffraction (LEED), scanning tunneling microscopy (STM), surface extended X-ray absorption fine structure (SEXAFS) spectroscopy and angle-integrated core-level photoemission electron spectroscopy (PES) were employed to measure the surface symmetry, defect structure, relevant bond lengths, atomic coordination and electronic structure. By employing a multi-technique approach, it is possible to correlate changes in the geometric structure to specific features of the core-level lineshape of the substrate. This allows for the assignment of components of the core-level lineshape to be assigned to specific surface and near-surface atoms.
Date: August 1, 1993
Creator: Richter, M.
Object Type: Report
System: The UNT Digital Library
Calcining process emission screening test for polychlorinated dibenzodioxins (open access)

Calcining process emission screening test for polychlorinated dibenzodioxins

Since 1963, the Idaho Chemical Processing Plant (ICPP) at the Idaho National Engineering Laboratory has been using fluidized-bed technology to convert high-level radioactive liquid waste into a granular solid for interim storage before eventual long-term storage. The calcining process uses kerosene, oxygen, air and a cooling jacket to maintain the temperature of the fluidized bed at approximately 400 C. The solids are moved to storage bins and the combustion gases and fine particles are swept from the bed to an atmospheric protection system. This atmospheric protection system includes a cyclone to collect larger particles; a nitric acid scrubber to cool gases and collect small particles; a condenser to reduce water content; silica gel beds to adsorb volatile ruthenium, water, and hydrocarbons; and a series of high efficiency particulate air (HEPA) filters to collect minute particles. The calcination process solidifies waste solutions containing molar levels of acid, nitrate, fluoride, zirconium, aluminum, iron, boron, and cadmium; minor levels (<0.1%) of various fission products and organics; and trace levels (<50 ppm) of chloride and sulfate. Because the process burns kerosene in the presence of other organics and chloride salts; the calciner was considered a potential production source of polychlorinated dibenzo-p-dioxins (PCDD). Therefore, it …
Date: August 1, 1993
Creator: Hartenstein, S.D.
Object Type: Report
System: The UNT Digital Library
Technology development program for Idaho Chemical Processing Plant spent fuel and waste management (open access)

Technology development program for Idaho Chemical Processing Plant spent fuel and waste management

Acidic high-level radioactive waste (HLW) resulting from fuel reprocessing at the Idaho Chemical Processing Plant (ICPP) for the U.S. Department of Energy (DOE) has been solidified to a calcine since 1963 and stored in stainless steel bins enclosed by concrete vaults. Several different types of unprocessed irradiated DOE-owned fuels are also in storage at the ICPP. In April, 1992, DOE announced that spent fuel would no longer be reprocessed to recover enriched uranium and called for a shutdown of the reprocessing facilities at the ICPP. A new Spent Fuel and HLW Technology Development program was subsequently initiated to develop technologies for immobilizing ICPP spent fuels and HLW for disposal, in accordance with the Nuclear Waste Policy Act. The Program elements include Systems Analysis, Graphite Fuel Disposal, Other Spent Fuel Disposal, Sodium-Bearing Liquid Waste Processing, Calcine Immobilization, and Metal Recycle/Waste Minimization. This paper presents an overview of the ICPP radioactive wastes and current spent fuels, and describes the Spent Fuel and HLW Technology program in more detail.
Date: August 1, 1993
Creator: Ermold, L.F.; Knecht, D.A.; Hogg, G.W. & Olson, A.L.
Object Type: Report
System: The UNT Digital Library
Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain Site characterization study; Progress report, April 1, 1993--June 30, 1993 (open access)

Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain Site characterization study; Progress report, April 1, 1993--June 30, 1993

This report is in two parts one for the fluorinated benzoic acids and one for the fluorinated aliphatic acids. The assumptions made in the report regarding the amount of tracer that will be used, dilution of the tracer during the test and the length of exposure (if any) to individuals drinking the water were made by the authors. These assumptions must really come from the USGS hydrologists in charge of the c-well tracer testing program. Accurate estimates of dilution of the tracer during the test are also important because of solubility limitations of some of the tracers. Three of the difluorobenzoic acids have relatively low solubilities and may not be usable if the dilution estimates are large. The toxicologist that reviewed the document agreed with our conclusion that the fluorinated benzoic and toluic acids do not represent a health hazard if used under the conditions as outlined in the report. We are currently testing 15 of these compounds, and if even if three difluorobenzoic acids cannot be used because of solubility limitations we will still have 12 tracers. The toxicologist felt that the aliphatic fluorinated acids potentially present more of a health risk than the aromatic. This assessment was based …
Date: August 1, 1993
Creator: Dombrowski, Tonya & Stetzenbach, Klaus
Object Type: Report
System: The UNT Digital Library
Identification of subsurface microorganisms at Yucca Mountain; Fourth quarterly report (open access)

Identification of subsurface microorganisms at Yucca Mountain; Fourth quarterly report

Bacteria isolated from water samples collected in a series of ground water springs have been isolated, enumerated, and identified from twenty six sites. Ten sites were sampled in Death Valley, California and sixteen sites were sampled in Ash Meadows, Nevada. Replicate samples were collected and tested from four locations. All water samples were collected in conjunction with the HRC chemistry group conducting ground water fingerprinting studies. The protocol for collection of samples, as described in the 3rd quarterly report, specified aseptic collection in sterile screw-capped containers and transportation on ice to the HRC microbiology laboratory. All samples were inoculated by spread plating onto R2A (Difco Laboratories, Detroit, MI) bacterial culture medium. the R2A plates were then incubated at 28{degrees} for 5--7 days and colonies wee counted with the aid of a grid template and magnifying lens.
Date: August 1, 1993
Creator: Stetzenbach, Linda D.
Object Type: Report
System: The UNT Digital Library
Rural migration in southern Nevada (open access)

Rural migration in southern Nevada

This study reviews the history of migration in two rural counties in Southern Nevada. It is part of a larger study about the impact of a proposed high-level nuclear waste repository on in- and out-migration patterns in the state. The historical record suggests a boom and bust economic cycle has predominated in the region for the past century creating conditions that should be taken into account by decision makers when ascertaining the long-term impacts of the proposed repository.
Date: August 1, 1993
Creator: Mosser, Duane & Soden, Dennis L.
Object Type: Article
System: The UNT Digital Library
Word images as policy instruments: Lessons from the Yucca Mountain Controversey (open access)

Word images as policy instruments: Lessons from the Yucca Mountain Controversey

A study is described which explores word images which have developed about nuclear issues by Nevadans. The study is based on results of a survey conducted regarding issues related to the Yucca Mountain repository.
Date: August 1, 1993
Creator: Conary, Janet S.; Soden, Dennis L. & Carns, Donald E.
Object Type: Article
System: The UNT Digital Library
Measuring liquid properties with smooth- and textured-surface resonators (open access)

Measuring liquid properties with smooth- and textured-surface resonators

The sensitivity of quartz resonators to surface mass accumulation enables their use in a number of sensing applications. The linear change in resonant frequency that occurs with mass accumulation allows the device to function as a general-purpose gravimetric detector or ``microbalance.`` The device is easily instrumented as a sensor by incorporating it as the frequency-control element of an oscillator circuit. The response of thickness shear mode (TSM) resonators in liquids is examined. Smooth-surface devices, which viscously entrain a layer of contacting liquid, respond to the product of liquid density and viscosity. Textured-surface devices, which also trap liquid in surface features, exhibit an additional response that depends on liquid density alone. Combining smooth and textured resonators in a monolithic sensor allows simultaneous measurement of liquid density and viscosity.
Date: August 1, 1993
Creator: Martin, S. J.; Wessendorf, K. O.; Gebert, C. T.; Frye, G. C.; Cernosek, R. W.; Casaus, L. et al.
Object Type: Report
System: The UNT Digital Library
Measurement and Modeling of Advanced Coal Conversion Processes, Volume III (open access)

Measurement and Modeling of Advanced Coal Conversion Processes, Volume III

A generalized one-dimensional, heterogeneous, steady-state, fixed-bed model for coal gasification and combustion is presented. The model, FBED-1, is a design and analysis tool that can be used to simulate a variety of gasification, devolatilization, and combustion processes. The model considers separate gas and solid temperatures, axially variable solid and gas flow rates, variable bed void fraction, coal drying, devolatilization based on chemical functional group composition, depolymerization, vaporization and crosslinking, oxidation, and gasification of char, and partial equilibrium in the gas phase.
Date: August 1, 1993
Creator: Ghani, M. U.; Hobbs, M. L. & Hamblen, D. G.
Object Type: Report
System: The UNT Digital Library
Advanced batteries for electric vehicle applications (open access)

Advanced batteries for electric vehicle applications

A technology assessment is given for electric batteries with potential for use in electric powered vehicles. Parameters considered include: specific energy, specific power, energy density, power density, cycle life, service life, recharge time, and selling price. Near term batteries include: nickel/cadmium and lead-acid batteries. Mid term batteries include: sodium/sulfur, sodium/nickel chloride, nickel/metal hydride, zinc/air, zinc/bromine, and nickel/iron systems. Long term batteries include: lithium/iron disulfide and lithium- polymer systems. Performance and life testing data for these systems are discussed. (GHH)
Date: August 1, 1993
Creator: Henriksen, G.L.
Object Type: Report
System: The UNT Digital Library
Role of pressure in the study of fullerenes (open access)

Role of pressure in the study of fullerenes

Although fullerenes and their compounds are very new and exhibit new phenomena, pressure has already been an important factor in the characterization and study of these materials. In order to illustrate this, the authors will review collaborative studies on: (i) the effect of pressure on alkali and alkaline earth doped C{sub 60} superconductors, (ii) the effect of pressure and pressure medium on the ordering temperature of C{sub 60}, and (iii) the role of pressure in the study of the feasibility of using C{sub 60} as ``lattice sieves`` for separation of gases.
Date: August 1, 1993
Creator: Schirber, J. E.; Samara, G. A.; Morosin, B.; Assink, R.; Loy, D.; Wang, H. et al.
Object Type: Article
System: The UNT Digital Library
An approach to validation of thermomechanical models (open access)

An approach to validation of thermomechanical models

Thermomechanical models are being developed to support the design of an Exploratory Studies Facility (ESF) and a potential high-level nuclear waste repository at Yucca Mountain, Nevada. These models are used for preclosure design of underground openings, such as access drifts, emplacement drifts, and waste emplacement boreholes; and in support of postclosure issue resolution relating to waste canister performance, disturbance of the hydrological properties of the host rock, and overall system performance assessment. For both design and performance assessment, the purpose of using models in analyses is to better understand and quantify some phenomenon or process. Therefore, validation is an important process that must be pursued in conjunction with the development and application of models. The Site Characterization Plan (SCP) addressed some general aspects of model validation, but no specific approach has, as yet, been developed for either design or performance assessment models. This paper will discuss a proposed process for thermomechanical model validation and will focus on the use of laboratory and in situ experiments as part of the validation process. The process may be generic enough in nature that it could be applied to the validation of other types of models, for example, models of unsaturated hydrologic flow.
Date: August 1, 1993
Creator: Costin, L.S.; Hardy, M.P. & Brechtel, C.E.
Object Type: Article
System: The UNT Digital Library
The role of multiple barriers in assuring waste package reliability; Yucca Mountain Project (open access)

The role of multiple barriers in assuring waste package reliability; Yucca Mountain Project

Yucca Mountain in southwestern Nevada is being studied as a potential repository site for the permanent storage of high-level nuclear waste. Regulators have set performance standards that the potential repository must meet in order to obtain regulatory approval. Nuclear Regulatory Commission (NRC) regulations state that containment of radioactivity must be ``substantially complete`` for the first 1000 years after closure of the facility. Thereafter, the acceptable annual limit on releases is 1/100,000 of each radionuclide remaining in the inventory after 1000 years. To demonstrate that the potential facility is in compliance with the regulations, it is necessary to obtain some understanding of the probability distribution of the cumulative quantity of releases by certain time points. This paper will discuss the probability distribution of waste container lifetimes and how the understanding of this distribution will play a role in finding the distribution of the release quantities over time. It will be shown that, for reasonable assumptions about the process of barrier failure, the reliability of a multiple-barrier container can be achieved and demonstrated much more readily than a container consisting of a single barrier. The discussion will focus primarily on the requirement of substantially complete containment for the first 1000 years.
Date: August 1, 1993
Creator: Bradford, R. M.
Object Type: Report
System: The UNT Digital Library
Foreign travel report: Visits to UK, Belgium, Germany, and France to benchmark European spent fuel and waste management technology (open access)

Foreign travel report: Visits to UK, Belgium, Germany, and France to benchmark European spent fuel and waste management technology

The ICPP WINCO Spent Fuel and Waste Management Development Program recently was funded by DOE-EM to develop new technologies for immobilizing ICPP spent fuels, sodium-bearing liquid waste, and calcine to a form suitable for disposal. European organizations are heavily involved, in some cases on an industrial scale in areas of waste management, including spent fuel disposal and HLW vitrification. The purpose of this trip was to acquire first-hand European efforts in handling of spent reactor fuel and nuclear waste management, including their processing and technical capabilities as well as their future planning. Even though some differences exist in European and U.S. DOE waste compositions and regulations, many aspects of the European technologies may be applicable to the U.S. efforts, and several areas offer potential for technical collaboration.
Date: August 1, 1993
Creator: Ermold, L.F. & Knecht, D.A.
Object Type: Report
System: The UNT Digital Library
Unconfined compression experiments on Topopah Spring Member tuff at 22{degrees}C and a strain rate of 10{sup {minus}9} s{sup {minus}1}: Data report; Yucca Mountain Site Characterization Project (open access)

Unconfined compression experiments on Topopah Spring Member tuff at 22{degrees}C and a strain rate of 10{sup {minus}9} s{sup {minus}1}: Data report; Yucca Mountain Site Characterization Project

Experiment results are presented for unconfined compressive strength and elastic moduli of tuffaceous rocks from Busted Butte near Yucca Mountain, Nevada. The data have been compiled for the Yucca Mountain Site Characterization Project Site and Engineering Properties Data Base. Experiments were conducted on water-saturated specimens of the potential nuclear waste repository horizon Topopah Spring Member tuff (thermal/mechanical unit TSw2). The influence of strain rate on mechanical properties of the tuff was examined by loading six specimens in uniaxial compression at a strain rate of 10{sup {minus}9} s{sup {minus}1}. The experiments performed under ambient pressure and temperature conditions and conformed to Technical Procedure 91, titled ``Unconfined Compression Experiments at 22{degrees}C and a Strain Rate of 10{sup {minus}9} s{sup {minus}1}.`` The mean and standard deviation values of ultimate strength, Young`s modulus and Poisson`s ratio determined from these experiments are 85.4{plus_minus}21.7 MPa, 33.9{plus_minus}4.6 GPa, and 0.09{plus_minus}0.07, respectively.
Date: August 1, 1993
Creator: Martin, R. J., III; Boyd, P. J.; Noel, J. S. & Price, R. H.
Object Type: Report
System: The UNT Digital Library
Fundamental studies of fluid mechanics and stability in porous media. Progress report (open access)

Fundamental studies of fluid mechanics and stability in porous media. Progress report

This progress report covers our work over the last grant period (1990-1993). Work has been in the following areas: semi-analytical studies of enhanced energy transport in natural convection due to time dependent body forces; large scale simulations of non-linear instabilities in porous media flow for situations of interest in petroleum recovery; analytical studies of `chimney` formation in unstable freezing mixtures; analytical and experimental studies of contact line dynamics for Newtonian and non-Newtonian fluids; and large scale numerical simulations of shear instabilities of viscoelastic fluids.
Date: August 1, 1993
Creator: Homsy, G.M.
Object Type: Report
System: The UNT Digital Library
Development and testing of a commercial-scale coal-fired combustion system: Phase 3, Quarterly technical progress report No. 11, April 1, 1993--June 30, 1993 (open access)

Development and testing of a commercial-scale coal-fired combustion system: Phase 3, Quarterly technical progress report No. 11, April 1, 1993--June 30, 1993

Within the commercial sector, oil and natural gas are the predominant fuels used to meet the space-heating needs of schools, office buildings, apartment complexes, and other similar structures. In general, these buildings require firing rates of 1 to 10 million Btu/hr. The objective of this program is to demonstrate the technical and economic viability of a coal-fired combustion system for this sector. The commercial-scale coal-water slurry (CWS) fired space heating system is a scale-up of a CWS-fired residential warm-air heating system developed by Tecogen under contract to the Department of Energy (DOE), Pittsburgh Energy Technology Center. This system included a patented nonslagging combustor known as IRIS, for Inertial Reactor with Internal Separation. The combustor concept employs centrifugal forces combined with a staged combustion process to achieve high carbon conversion efficiencies and low nitrogen oxides generation. Along with the necessary fuel storage and delivery, heat recovery, and control equipment, the system includes pollution control devices to meet targeted values of SO{sub 2} and particulate emissions. In general, the system is designed to match the reliability, safety, turndown, and ignition performance of gas or oil- fired systems. During the past quarter, installation of the slurry production facility and coal water slurry fired …
Date: August 1, 1993
Creator: Litka, A. F. & Breault, R. W.
Object Type: Report
System: The UNT Digital Library
Linearly convergent inexact proximal point algorithm for minimization. Revision 1 (open access)

Linearly convergent inexact proximal point algorithm for minimization. Revision 1

In this paper, we propose a linearly convergent inexact PPA for minimization, where the inner loop stops when the relative reduction on the residue (defined as the objective value minus the optimal value) of the inner loop subproblem meets some preassigned constant. This inner loop stopping criterion can be achieved in a fixed number of iterations if the inner loop algorithm has a linear rate on the regularized subproblems. Therefore the algorithm is able to avoid the computationally expensive process of solving the inner loop subproblems exactly or asymptotically accurately; a process required by most of the other linearly convergent PPAs. As applications of this inexact PPA, we develop linearly convergent iteration schemes for minimizing functions with singular Hessian matrices, and for solving hemiquadratic extended linear-quadratic programming problems. We also prove that Correa-Lemarechal`s ``implementable form`` of PPA converges linearly under mild conditions.
Date: August 1, 1993
Creator: Zhu, C.
Object Type: Report
System: The UNT Digital Library
Simulation and performance analysis of triple-effect absorption cycles (open access)

Simulation and performance analysis of triple-effect absorption cycles

Performance simulation has been carried out for several triple-effect cycles, designed to improve utilization of high temperature heat sources for absorption systems and capable of substantial performance improvement over equivalent double-effect cycles. The systems investigated include the three-condenser-three-desorber (3C3D) cycle, forming an extension of the conventional double-effect one; the recently proposed Double Condenser Coupled (DCC) cycle which recovers heat from the hot condensate leaving the high temperature condensers and adds it to the lower temperature desorbers; and the dual loop cycle comprising two complete single-effect loops, recovering heat from the condenser and absorber of one loop to the desorber of the other loop and generating a cooling effect in the evaporators of both loops. A modular computer code for simulation of absorption systems was used to investigate the performances of the cycles and compare them on an equivalent basis, by selecting a common reference design and operating condition. Performance simulation was carried out over a range of operating conditions, including some investigation of the influence of the design parameters. Coefficients of performance ranging from 1.27 for the series-flow 3C3D to 1.73 for the parallel-flow DCC have been calculated at the design point. The relative merits and shortcomings of the different …
Date: August 1, 1993
Creator: Grossman, G.; Wilk, M. & DeVault, R.C.
Object Type: Article
System: The UNT Digital Library
Dialogs on the Yucca Mountain controversy. Special report No. 10 (open access)

Dialogs on the Yucca Mountain controversy. Special report No. 10

In an attempt to resolve the controversial issue of tectonic and hydrologic stability of the Yucca Mountain region, the National Academy of Sciences established a Panel on Coupled Hydrologic/Tectonic/HydrothermaI Systems. The Panel has recently released it`s findings in a report entitled Ground Water at Yucca Mountain: How High Can It Rise? The representation of data and the scientific validity of this report was the subject of comprehensive evaluations and reviews which has led to correspondence between Dr. Charles Archarnbeau and Dr. Frank Press, the President of the National Academy of Sciences. All such correspondence prior to April 9, 1993 is covered by TRAC Special Report No. 5, {open_quotes}Dialogs on the Yucca Mountain Controversy.{close_quotes} The present report represents a continuation of the dialog between Dr. Archambeau and Dr. Press; specifically the letter from Dr. Press to Dr. Archambeau dated April 9, 1993 and Archambeau`s response to Press, dated August 19, 1993. In addition to the correspondence between Press and Archambeau, a series of recent reports by other investigators, referred to in the correspondence from Archambeau, are included in this report and document new data and inferences of importance for resolution of the question of suitability of the Yucca Mountain site as …
Date: August 1, 1993
Creator: Schluter, C.M. & Szymanski, J.S.
Object Type: Report
System: The UNT Digital Library
Measurement techniques development. Final report (open access)

Measurement techniques development. Final report

This final report covers work done through the period of performance 16 January 1991 to 16 January 1993. The work has been in support of the drive symmetry and hydrodynamic implosion experiments which Lawrence Livermore National Laboratory (LLNL) Group P-4 is designing and fielding at the NOVA laser facility at LLNL. The work done involves experimental support in obtaining data, analysis of the data, and experimental design.
Date: August 1, 1993
Creator: Delamater, N.D.
Object Type: Report
System: The UNT Digital Library
Alpha and gamma radiation effects on air-water systems at high gas/liquid ratios (open access)

Alpha and gamma radiation effects on air-water systems at high gas/liquid ratios

Radiolysis tests were conducted on air-water systems to examine the effects of radiation on liquid phase chemistry under high gas/liquid volume (G/L) ratios that are characteristic of an unsaturated nuclear waste repository setting. Test parameters included temperatures of 25, 90, and 200{degrees}C; gamma vs. alpha radiation; dose rates of {approximately}3500 and 50,000 rad/h; and G/L ratios of 10 and 100. Formate, oxalate, and total organic carbon contents increased during irradiation of the air-water systems in gamma and alpha tests at low-dose rate ({approximately}3500 rad/h). Increases in organic components were not observed for tests run at 200{degrees}C or high-dose rates (50,000 rad/h). In the tests where increases in organics occurred, the formate and oxalate were preferentially enriched in solutions that were rinsed from the test vessel walls. Nitrate (NO{sub 3}{sup {minus}}) is the dominant anion produced during the radiolysis reactions. Significant nitrite (NO{sub 2}{sup {minus}}) also occurs in some high-dose rate tests, with the reduced form of nitrogen possibly resulting from reactions with the test vessels. These results indicate that nitrogen acids are being produced and concentrated in the limited quantities of solution present in the tests. Nitrate + nitrite production varied inversely with temperature, with the lowest quantities being detected …
Date: August 1, 1993
Creator: Wronkiewicz, D.J. & Bates, J.K.
Object Type: Report
System: The UNT Digital Library