New Neutron Rich Nuclei Near {sup 208}Pb (open access)

New Neutron Rich Nuclei Near {sup 208}Pb

The level properties near the stable doubly-magic nuclei formed the experimental grounds for the theoretical description of nuclear structure. However with a departure from the beta-stability line, the classical well-established shell structure might be modified. In particular, it may even vanish for extremely exotic neutron-rich nuclei near the neutron-drip line. Presently, it is impossible to verify such predictions by a direct experimental studies of these exotic objects. However, one may try to observe and understand the evolution of the nuclear structure while departing in the experiment as far as possible from the stable nuclei. An extension of experimental nuclear structure studies towards the nuclei characterized by high neutron excess is crucial for such verifications as well as for the {tau}-process nucleosynthesis scenario. Heavy neutron-rich nuclei, south-east of doubly-magic {sup 208}Pb, were always very difficult to produce and investigate. The nuclei like {sup 218}Po and {sup 214}Pb or {sup 210}Tl marked the border line of known nuclei from the beginning of the radioactivity era for over ninety years. To illustrate the difficulties, one can refer to the experiments employing the on-line mass separator technique. A spallation of heavy targets like {sup 232}Th and {sup 238}U by high-energy protons was proven as …
Date: November 13, 1998
Creator: Aeystoe, J.; Andreyev, A.; Evensen, A.-H.; Hoff, P.; Huhta, M.; Huyse, M. et al.
Object Type: Article
System: The UNT Digital Library
A new paradigm to establish the safety basis for nuclear explosives operations (open access)

A new paradigm to establish the safety basis for nuclear explosives operations

The U. S. Department of Energy (DOE) has recognized that safety assurance requires a balance of institutional and engineering approaches as part of an ongoing safety process. This recognition formed the basis for a new approach to nuclear explosive safety with a focus on the inherent value of the examination process, as opposed to an absolute justification of the nuclear explosive operation against some preddined acceptance criteria. This new approach to safety is reflected in recent DOE Orders and Standards in that there is no requirement that quantitative risk assessment or risk quantification be used in meeting requirements. Furthermore, there is no requirement to compare hazard and accident analysis results against numerical acceptance criteria. This paper discusses the evolution of the DOE nuclear explosive safety orders and compares those with facility safety requirements. The DOE nuclear explosive safety process is examined, and an example application is discussed with emphasis on identification of safety measures and controls.
Date: September 13, 1998
Creator: Fischer, Stewart R., Clement, Steven, Stack, Desmond W.
Object Type: Article
System: The UNT Digital Library
A New Simplified System for the Evaluation of BNCT Pharmaceuticals (open access)

A New Simplified System for the Evaluation of BNCT Pharmaceuticals

A system for testing potential BNCT pharmaceuticals in cell cultures has been developed with the cooperation of Oak Ridge National Laboratory (ORNL), the University of Tennessee Chemistry Department and the University of Tennessee Nuclear Engineering Department. A BNCT test model has been established with the use of the human lung cancer cell line A 549. These cells were maintained in standard laboratory facilities and subjected to boronated chemicals. Following toxicity studies the human luug cancer cells were exposed to {sup 252}Cf neutron sources provided by the Radiochemical Engineering Development Center (REDC) at ORNL The isotope {sup 252}Cf performs effectively for BNCT applications. The neutron spectrum is similar to that of a reactor fission source with an average energy of 2.1 MeV. A 50 mg source of {sup 252}Cf moderated by water provides a source on the order of 1 x 10{sup 9} thermal neutrons/cm{sup 2}/sec at a distance of 3 cm. The half-life of {sup 252}Cf is 2.65 years, and thus may provide a simple and reliable source of neutrons for BNCT in locations without suitable nuclear reactors. The REDC of ORNL stores and processes the U.S. stockpile of {sup 252}Cf.
Date: September 13, 1998
Creator: Byrne, T. E.; Kabalka, G. W.; Martin, R. C. & Miller, L. F.
Object Type: Article
System: The UNT Digital Library
Next-generation laser for inertial confinement fusion (open access)

Next-generation laser for inertial confinement fusion

We are developing and building the ''Mercury'' laser system as the first in a series of a new generation of diode-pumped solid-state lasers (DPSSL) for advanced high energy density (HED) physics experiments at LLNL. Mercury will be the first integrated demonstration of a scalable laser architecture compatible with advanced Inertial Confinement Fusion (ICF) goals. Primary performance goals include 10% efficiencies at 10 Hz and a <10 ns pulse with l {omega} energies of 100 J and with 2 {omega}/3 {omega} frequency conversion. Achieving this performance will provide a near term capability for HED experiments and prove the potential of DPSSLs for inertial fusion energy (IFE).
Date: March 13, 1998
Creator: Marshall, C.; Bibeau, C.; Bayramian, A.; Beach, R.; Ebbers, C. A.; Emanuel, M. et al.
Object Type: Article
System: The UNT Digital Library
NWIS MEASUREMENTS FOR URANIUM METAL ANNULAR CASTINGS (open access)

NWIS MEASUREMENTS FOR URANIUM METAL ANNULAR CASTINGS

This report describes measurements performed with annular uranium metal castings of different enrichments to investigate the use of {sup 252}Cf-source-driven noise analysis measurements as a means to quantify the amount of special nuclear material (SNM) in the casting. This work in FY 97 was sponsored by the Oak Ridge Y-12 Plant and the DOE Office of Technology Development Programs. Previous measurements and calculational studies have shown that many of the signatures obtained from the source-driven measurement are very sensitive to fissile mass. Measurements were performed to assess the applicability of this method to standard annular uranium metal castings at the Oak Ridge Y-12 plant under verification by the International Atomic Energy Agency (IAEA) using the Nuclear Weapons Identification System (NWIS) processor. Before the measurements with different enrichments, a limited study of source-detector-casting moderator configurations was performed to enhance the correlated information. These configurations consisted of a casting with no reflector and with various thicknesses of polyethylene reflectors up to 10.16 cm in 2.54 cm steps. The polyethylene moderator thickness of 7.62 cm was used for measurements with castings of different enrichments reported here. The sensitivity of the measured parameters to fissile mass was investigated using four castings each with a …
Date: March 13, 1998
Creator: MATTINGLY, J.K.; VALENTINE, T.E. & MIHALCZO, J.T.
Object Type: Report
System: The UNT Digital Library
Office of Inspector General audit of alternatives to testing at the Tonopah Test Range (open access)

Office of Inspector General audit of alternatives to testing at the Tonopah Test Range

Since the 1950s, the Department of Energy (DOE) and its predecessor agencies have done weapons program testing at the Tonopah Test Range (Tonopah). Beginning the in 1990s, DOE`s testing at Tonopah declined dramatically. This decline was coincident with the signing of various international treaties, the end of the Cold War, and the movement of some types of tests to other ranges. As a result, Tonopah was left with some bomb and work-for-others testing. The objective of this audit was to determine if there were viable, cost effective alternatives to testing at Tonopah. During the early 1990s, DOE`s Albuquerque Operations Office (Albuquerque) and Sandia National Laboratories (Sandia), which operates Tonopah for DOE, explored the alternative of testing elsewhere. Some of the data gathered by Albuquerque and Sandia provided indications that testing at another range would be practical and economical. This audit followed up on the Albuquerque/Sandia studies and also indicated that testing could be done elsewhere, at a potential cost savings of several million dollars annually. Therefore, it was recommended that Albuquerque conduct a comprehensive study of all testing alternatives. Albuquerque agreed to implement this recommendation but raised technical questions regarding issues such as environmental permits, scheduling flexibility, and cost components, …
Date: March 13, 1998
Creator: Friedman, G.H.
Object Type: Report
System: The UNT Digital Library
Optimization of Ultrasonic Fabric Cleaning (open access)

Optimization of Ultrasonic Fabric Cleaning

The fundamental purpose of this project was to research and develop a process that would reduce the cost and improve the environmental efficiency of the present dry-cleaning industry. This second phase of research (see report KCP-94-1006 for information gathered during the first phase) was intended to allow the optimal integration of all factors of ultrasonic fabric cleaning. For this phase, Garment Care performed an extensive literature search and gathered data from other researchers worldwide. The Garment Care-AlliedSignal team developed the requirements for a prototype cleaning tank for studies and acquired that tank and the additional equipment required to use it properly. Garment Care and AlliedSignal acquired the transducers and generators from Surftran Martin-Walter in Sterling Heights, Michigan. Amway's Kelly Haley developed the test protocol, supplied hundreds of test swatches, gathered the data on the swatches before and after the tests, assisted with the cleaning tests, and prepared the final analysis of the results. AlliedSignal personnel, in conjunction with Amway and Garment Care staff, performed all the tests. Additional planning is under way for future testing by outside research facilities. The final results indicated repeatable performance and good results for single layered fabric swatches. Swatches that were cleaned as a ''sandwich,'' …
Date: May 13, 1998
Creator: Hand, T.E.
Object Type: Report
System: The UNT Digital Library
The Performance of the HRIBF Recoil Mass Spectrometry (open access)

The Performance of the HRIBF Recoil Mass Spectrometry

The Recoil Mass Spectrometer (RMS) is a mass separator located at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory. This paper describes the RMS, its performance, its detector systems, and discusses some experiments to illustrate its capabilities.
Date: November 13, 1998
Creator: Ginter, T. N.
Object Type: Article
System: The UNT Digital Library
Photo-induced electron transfer from a conducting polymer to buckminsterfullerene: A molecular approach to high efficiency photovoltaic cells. Final report (open access)

Photo-induced electron transfer from a conducting polymer to buckminsterfullerene: A molecular approach to high efficiency photovoltaic cells. Final report

For photovoltaic cells made with pure conjugated polymers, energy conversion efficiencies were typically 10{sup {minus}3}--10{sup {minus}2}%, too low to be used in practical applications. The recent discovery of photoinduced electron transfer in composites of conducting polymers (as donors) and buckminsterfullerene, C{sub 60}, and its derivatives (as acceptors) provided a molecular approach to high efficiency photovoltaic conversion. Since the time scale for photoinduced charge transfer is subpicosecond, more than 10{sup 3} times faster than the radiative or nonradiative decay of photo-excitations, the quantum efficiency for charge transfer and charge separation from donor to acceptor is close to unity. Thus, photoinduced charge transfer across a donor/acceptor (D/A) interface provides an effective method of overcome early time carrier recombination in organic systems and thus to enhance the optoelectronic response of these materials. Progress toward creating bulk D/A heterojunction materials is described by summarizing two publications which resulted from this research, namely: Plastic photovoltaic cells made with donor-acceptor composites -- Enhanced carrier collection efficiency via a network of internal heterojunctions; and Charge separation and photovoltaic conversion in polymer composites with internal donor/acceptor heterojunctions.
Date: August 13, 1998
Creator: Heeger, A.J.
Object Type: Report
System: The UNT Digital Library
Plutonium immobilization form evaluation (open access)

Plutonium immobilization form evaluation

The 1994 National Academy of Sciences study and the 1997 assessment by DOE`s Office of Nonproliferation and National Security have emphasized the importance of the overall objectives of the Plutonium Disposition Program of beginning disposition rapidly. President Clinton and other leaders of the G-7 plus one (`Political Eight`) group of states, at the Moscow Nuclear Safety And Security Summit in April 1996, agreed on the objectives of accomplishing disposition of excess fissile material as soon as practicable. To meet these objectives, DOE has laid out an aggressive schedule in which large-scale immobilization operations would begin in 2005. Lawrence Livermore National Laboratory (LLNL), the lead laboratory for the development of Pu immobilization technologies for the Department of Energy`s Office of Fissile Materials Disposition (MD), was requested by MD to recommend the preferred immobilization form and technology for the disposition of excess weapons-usable Pu. In a series of three separate evaluations, the technologies for the candidate glass and ceramic forms were compared against criteria and metrics that reflect programmatic and technical objectives: (1) Evaluation of the R&D and engineering data for the two forms against the decision criteria/metrics by a technical evaluation panel comprising experts from within the immobilization program. (2) Integrated …
Date: February 13, 1998
Creator: Gray, L. W.
Object Type: Article
System: The UNT Digital Library
Polarization smoothing for the National Ignition Facility (open access)

Polarization smoothing for the National Ignition Facility

Polarization smoothing (PS) is the illumination of the target with two distinct and orthogonally polarized speckle patterns. Since these two polarizations do not interfere, the intensity patterns add incoherently and thus the contrast of the intensity nonuniformity can be reduced by a factor of {radical}2 in addition to any reduction achieved by temporal smoothing techniques. Smoothing by PS is completely effective on an instantaneous basis and is therefore of particular interest for the suppression of laser plasma instabilities, which have a very rapid response time. The various implementations of PS are considered and their impact, in conjunction with temporal smoothing methods, on the spatial spectrum of the target illumination is analyzed.
Date: August 13, 1998
Creator: Rothenberg, J F
Object Type: Article
System: The UNT Digital Library
Post Waterflood C02 Miscible Flood in Light Oil Fluvial-Dominated Deltaic Reservoirs (open access)

Post Waterflood C02 Miscible Flood in Light Oil Fluvial-Dominated Deltaic Reservoirs

Only one well remains in production in the Port Neches CO2 project; Kuhn #14. Production from this project is approaching economic limit and the project is nearing termination at this point. The work over to return Kuhn #38 to production failed and the well is currently shut in. All produced CO2 is currently being reinjected in the reservoir. The CO2 recycled volume is 2 MMCFD.
Date: January 13, 1998
Creator: Augustine, John
Object Type: Report
System: The UNT Digital Library
Post Waterflood C02 Miscible Flood in Light Oil Fluvial-Dominated Deltaic Reservoirs (open access)

Post Waterflood C02 Miscible Flood in Light Oil Fluvial-Dominated Deltaic Reservoirs

The only remaining active well, Kuhn #14, in the Port Neches CO2 project went off production in October 1997. Production from this project is reached economic limit and the project termination began in the last quarter of 1997.
Date: May 13, 1998
Creator: Tipton, Tim
Object Type: Report
System: The UNT Digital Library
Predicting flammable gas mixtures in Hanford double-contained receiver tanks (open access)

Predicting flammable gas mixtures in Hanford double-contained receiver tanks

This study presents a methodology to estimate the maximum concentrations of flammable gases (ammonia, hydrogen, and methane) which could exist in the vapor space of a double-contained receiver tank (DCRT). DCRTs are temporary storage tanks which receive highly radioactive liquid wastes from salt well pumping of Hanford single-shell tanks (SST). The methodology of this study could be used in other applications involving the storage and transfer of radioactive liquid wastes which generate or contain various dissolved flammable gases.
Date: May 13, 1998
Creator: Hedengren, D.C.
Object Type: Article
System: The UNT Digital Library
Preliminary pathway analysis for YMP preclosure biosphere dose assessment (open access)

Preliminary pathway analysis for YMP preclosure biosphere dose assessment

The preliminary preclosure biosphere dose assessment for the Yucca Mountain Project (YMP) involves the calculation of a radiation dose to a subsistence farmer living near the proposed Yucca Mountain repository. Eight radionuclides, H-3, Co-60, Kr-85, Sr-90, Ru-106, I-129, Cs-134, and Cs-137, are considered in this study. Radiation doses resulting from unit release rates of these radionuclides are analyzed. Total dose has been broken down into components that result from various exposure pathways. By using this approach, the most important pathways that deliver a radiation dose to a subsistence farmer can be clearly identified.
Date: May 13, 1998
Creator: Wu, D.; Liu, N.; Tappen, J. J. & Tung, C. H.
Object Type: Report
System: The UNT Digital Library
Proc. of the sixteenth symposium on energy engineering sciences, May 13-15, 1998, Argonne, IL. (open access)

Proc. of the sixteenth symposium on energy engineering sciences, May 13-15, 1998, Argonne, IL.

This Proceedings Volume includes the technical papers that were presented during the Sixteenth Symposium on Energy Engineering Sciences on May 13--15, 1998, at Argonne National Laboratory, Argonne, Illinois. The Symposium was structured into eight technical sessions, which included 30 individual presentations followed by discussion and interaction with the audience. A list of participants is appended to this volume. The DOE Office of Basic Energy Sciences (BES), of which Engineering Research is a component program, is responsible for the long-term, mission-oriented research in the Department. The Office has prime responsibility for establishing the basic scientific foundation upon which the Nation's future energy options will be identified, developed, and built. BES is committed to the generation of new knowledge necessary to solve present and future problems regarding energy exploration, production, conversion, and utilization, while maintaining respect for the environment. Consistent with the DOE/BES mission, the Engineering Research Program is charged with the identification, initiation, and management of fundamental research on broad, generic topics addressing energy-related engineering problems. Its stated goals are to improve and extend the body of knowledge underlying current engineering practice so as to create new options for enhancing energy savings and production, prolonging the useful life of energy-related structures …
Date: May 13, 1998
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Project W-030 safety class upgrade summary report (open access)

Project W-030 safety class upgrade summary report

This document presents a summary of safety class criteria for the 241-AY/AZ Tank Farm primary ventilation system upgrade under Project W-030, and recommends acceptance of the system as constructed, based on a review of supporting documentation.
Date: February 13, 1998
Creator: Kriskovich, J. R.
Object Type: Report
System: The UNT Digital Library
Proton Radioactivity Measurements at HRIBF: Ho, Lu, and Tm Isotopes (open access)

Proton Radioactivity Measurements at HRIBF: Ho, Lu, and Tm Isotopes

Two new isotopes, {sup 145}Tm and {sup 140}Ho and three isomers in previously known isotopes, {sup 141m}Ho, {sup 150m}Lu and {sup 151m}Lu have been discovered and studied via their decay by proton emission. These proton emitters were produced at the Holifield Radioactive Ion Beam Facility (HRIBF) by heavy-ion fusion-evaporation reactions, separated in A/Q with a recoil mass spectrometer (RMS), and detected in a double-sided silicon strip detector (DSSD). The decay energy and half-life was measured for each new emitter. An analysis in terms of a spherical shell model is applied to the Tm and Lu nuclei, but Ho is considerably deformed and requires a collective model interpretation.
Date: November 13, 1998
Creator: Akovali, Y.; Batchelder, J. C.; Bingham, C. R.; Davinson, T.; Ginter, T. N.; Gross, C. J. et al.
Object Type: Article
System: The UNT Digital Library
Quantum Suppression of beamstrahlung for future e+e- linear collider: an evaluation of QED backgrounds (open access)

Quantum Suppression of beamstrahlung for future e+e- linear collider: an evaluation of QED backgrounds

Beamstrahlung at interaction point may present severe limitations on linear collider performance. The approach to reduce this effect adopted for all current designs at 0.5 TeV range in center-of-mass energy will become more difficult and less effective at higher energy. We discuss the feasibility of an alternative approach, based on an effect known as quantum suppression of beamstrahlung, for future linear colliders at multi-TeV energy.
Date: October 13, 1998
Creator: Xie, Ming
Object Type: Article
System: The UNT Digital Library
Quarterly Technical Progress Report - West Hackberry Tertiary Project (open access)

Quarterly Technical Progress Report - West Hackberry Tertiary Project

The West Hackberry Tertiary Project is a field test of the concept that air injection can generate tertiary oil recovery through the Double Displacement Process is the gas displacement of a water invaded oil column for the purpose of recovering tertiary oil through gravity discharge. The novel aspect of this project is the use of air as the injection fluid.
Date: January 13, 1998
Creator: Cerveny, Bruce; Kragas, Tor & Gillham, Travis
Object Type: Report
System: The UNT Digital Library
Recent advances in indirect drive ICF target physics at LLNL (open access)

Recent advances in indirect drive ICF target physics at LLNL

In preparation for ignition on the National Ignition Facility, the Lawrence Livermore National Laboratory� s Inertial Confinement Fusion Program, working in collaboration with Los Alamos National Laboratory, Commissariat a 1� Energie Atomique (CEA), and Laboratory for Laser Energetics at the University of Rochester, has performed a broad range of experiments on the Nova and Omega lasers to test the fundamentals of the NIF target designs. These studies have refined our understanding of the important target physics, and have led to many of the specifications for the NIF laser and the cryogenic ignition targets. Our recent work has been focused in the areas of hohlraum energetics, symmetry, shock physics, and target design optimization & fabrication.
Date: January 13, 1998
Creator: Bernat, T. P.; Collins, G. W.; Haan, S.; Hammel, B. A.; Landen, O. L.; MacGowan, B. J. et al.
Object Type: Article
System: The UNT Digital Library
Renewable Energy Opportunity Assessment (open access)

Renewable Energy Opportunity Assessment

Presently, the US EPA is constructing a new complex at Research Triangle Park, North Carolina to consolidate its research operations in the Raleigh-Durham area. The National Computer Center (NCC) is currently in the design process and is planned for construction as partof this complex. Implementation of the new technologies can be planned as part of the normal construction process, and full credit for elimination of the conventional technologies can be taken. Several renewable technologies are specified in the current plans for the buildings. The objective of this study is to identify measures that are likely to be both technically and economically feasible.
Date: November 13, 1998
Creator: Hancock, E. & Mas, C.
Object Type: Report
System: The UNT Digital Library
Revision of the tensile database for V-Ti and V-Cr-Ti alloys tested at ANL. (open access)

Revision of the tensile database for V-Ti and V-Cr-Ti alloys tested at ANL.

The published database for the tensile properties of unirradiated and irradiated vanadium-based alloys tested at Argonne National Laboratory (ANL) has been reviewed. The alloys tested are in the ranges of V-(0-18)wt.%Ti and V-(4-15)wt.%Cr-(3-15)wt.%Ti. A consistent methodology, based on ASTM terminology and standards, has been used to re-analyze the unpublished load vs. displacement curves for 162 unirradiated samples and 91 irradiated samples to determine revised values for yield strength (YS), ultimate tensile strength (UTS), uniform elongation (UE) and total elongation (TE). The revised data set contains lower values for UE ({minus}5{+-}2% strain) and TE ({minus}4{+-}2% strain) than previously reported. Revised values for YS and UTS are consistent with the previously-published values in that they are within the scatter usually associated with these properties.
Date: January 13, 1998
Creator: Billone, M. C.
Object Type: Article
System: The UNT Digital Library
Ship-Track Clouds, Aerosol, and Ship Dynamic Effects; A Climate Perspective from Ship-Based Measurements (open access)

Ship-Track Clouds, Aerosol, and Ship Dynamic Effects; A Climate Perspective from Ship-Based Measurements

Ship-track clouds are marine boundary layer clouds that form behind ocean ships and are observed from satellites in the visible and near infrared. Ship-track clouds provide a rare opportunity to connect aerosol cloud condensation nuclei (CCN) emissions and observable changes in marine stratiform clouds. A very small change in the reflectivity of these eastern Pacific and Atlantic clouds (about 4%) provides a climate feedback of similar magnitude to doubling CO{sub 2} (increasing cloud reflectivity corresponds to global cooling). The Department of Energy sponsored research from 1991 to 1995 to study ship-track clouds including two ocean-based experiments in the summers of 1991 and 1994. These experiments showed that ship-track cloud properties were often more complex those related to a reduction of droplet size with an increase in number associated with increasing CCN from the ship's plume. The clouds showed evidence of morphological changes more likely to be associated with cloud dynamic effects either initiated by the increased CCN or directly by the ship's heat output or turbulent air wake. The fact that marine stratiform clouds, that are susceptible to ship track formation, are starved for both CCN and convective turbulence complicates the separation of the two effects.
Date: October 13, 1998
Creator: Porch, W.M.
Object Type: Article
System: The UNT Digital Library