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Imprinted spiral structures as neutron polarizers.

Description: Neutron diffraction from magnetic spiral structures is governed by strong selection rules for the polarization of the outgoing beam. When the sample is entirely of one chirality--for instance a right handed spiral--the neutrons diffracted by some Bragg reflections are fully polarized. While the scattering theory has been formulated long ago, attempts to controllably modify the population of left handed and right handed spiral domains in natural magnetic structures (which for instance occur in some rare earth metals) have been largely unsuccessful. In contrast, we have been able to imprint helical magnetic structures in La/Fe multilayers (each layer approximately 30 {angstrom} thick) simply by rotating the growing sample in a weak external field (30e). A first estimate is given of the efficiency of these multilayers as polarizers of neutron beams.
Date: October 7, 1998
Creator: Lohstroh, W.
Partner: UNT Libraries Government Documents Department

A,B,C`s of nuclear science

Description: This introductory level presentation contains information on nuclear structure, radioactivity, alpha decay, beta decay, gamma decay, half-life, nuclear reactions, fusion, fission, cosmic rays, and radiation protection. Nine experiments with procedures and test questions are included.
Date: August 7, 1995
Creator: Noto, V.A.; Norman, E.B.; Chan, Yuen-Dat; Dairiki, J.; Matis, H.S.; McMahan, M.A. et al.
Partner: UNT Libraries Government Documents Department

EPICS release 3.11.6 specific documentation -- Release notes for EPICS 3.11.6

Description: These notes cover the following: (1) directions for switching to production APS release R3.11.6; (2) unbundling of channel access clients; (3) access security; (4) channel access additions; synchronous time support; and (5) description of major differences between R3.11.3 and R3.11.6 Also included is a list of new and/or updated documentation for the program.
Date: June 7, 1994
Partner: UNT Libraries Government Documents Department

Natural Circulation in the Blanket Heat Removal System During a Loss-of-Pumping Accident (LOFA) Based on Initial Conceptual Design

Description: A transient natural convection model of the APT blanket primary heat removal (HR) system was developed to demonstrate that the blanket could be cooled for a sufficient period of time for long term cooling to be established following a loss-of-flow accident (LOFA). The particular case of interest in this report is a complete loss-of-pumping accident. For the accident scenario in which pumps are lost in both the target and blanket HR systems, natural convection provides effective cooling of the blanket for approximately 68 hours, and, if only the blanket HR systems are involved, natural convection is effective for approximately 210 hours. The heat sink for both of these accident scenarios is the assumed stagnant fluid and metal on the secondary sides of the heat exchangers.
Date: October 7, 1998
Creator: Hamm, L.L.
Partner: UNT Libraries Government Documents Department

Tank 241-AP-108 grab sampling and analysis plan

Description: This Sampling and Analysis Plan (SAP) will identify characterization objectives for sample collection, laboratory analytical evaluation, and reporting requirements for tank 241-AP-108 (AP 108). It is written in accordance with the Tank 241-AP-108 Tank Characterization Plan, the Tank Safety Screening Data Quality Objective, the 242-A Evaporator Liquid Effluent Retention Facility Data Quality Objectives, and the Data Quality Objectives for Tank Farms Waste Compatibility Program.
Date: February 7, 1997
Creator: Baldwin, J.H., Fluor Daniel Hanford
Partner: UNT Libraries Government Documents Department

B Plant process piping replacement feasibility study

Description: Reports on the feasibility of replacing existing embedded process piping with new more corrosion resistant piping between cells and between cells and a hot pipe trench of a Hanford Site style canyon facility. Provides concepts for replacement piping installation, and use of robotics to replace the use of the canyon crane as the primary means of performing/supporting facility modifications (eg, cell lining, pipe replacement, equipment reinstallation) and operational maintenenace.
Date: February 7, 1996
Creator: Howden, G.F.
Partner: UNT Libraries Government Documents Department

Ventilation system consequence calculations to support salt well pumping single-shell tank 241-A-101

Description: This document presents the radiological dose and toxicological exposure calculations for an accident scenario involved with the ventilation system used to support salt well pumping single-shell tank 241-A-101. This tank has been listed on the Hydrogen Watch List.
Date: May 7, 1997
Creator: Ryan, G.W.
Partner: UNT Libraries Government Documents Department

Simulations of laser-initiated stress waves

Description: We present a study of the short-time scale (< 250 ns) fluid dynamic response of water to a fiber-delivered laser pulse of variable energy and spatial profile. The laser pulse was deposited on a stress confinement time scale. The spatial profile was determined by the fiber core radius r (110 and 500 microns) and the water absorption coefficient {mu}{sub 2} (200 and 50 l/cm). Considering 2D cylindrical symmetry, the combination of fiber radius and absorption coefficient parameters can be characterized as near planar (1{mu}{sub 2} greater than r), symmetric (1/{mu}{sub 2}=r), and side-directed (1/{mu}{sub 2} less than r). The spatial profile study shows how the stress wave various as a function of geometry. For example, relatively small absorption coefficients can result in side-propagating shear and tensile fields.
Date: March 7, 1997
Creator: Maitland, D.J.; Celliers, P.; Amendt, P.; Da Silva, L.; London, R.A.; Matthews, D. et al.
Partner: UNT Libraries Government Documents Department

LEU conversion status of US research reactors, September 1996

Description: This paper summarizes the conversion status of research and test reactors in the United States from the use of fuels containing highly- enriched uranium (HEU, greater than or equal to 20%) to the use of fuels containing low-enriched uranium (LEU, < 20%). Estimates of the uranium densities required for conversion are made for reactors with power levels greater than or equal to 1 MW that are not currently involved in the LEU conversion process.
Date: October 7, 1996
Creator: Matos, J.E.
Partner: UNT Libraries Government Documents Department

Fabrication of MEMS Devices by Powder-Filling into DXRL-Formed Molds

Description: We have developed a variety of processes for fabricating components for micro devices based on deep x-ray lithography (DXRL). Although the techniques are applicable to many materials, we have demonstrated them using hard (Nd{sub 2}Fe{sub 14}B) and soft (Ni-Zn ferrite) magnetic materials because of the importance of these materials in magnetic micro-actuators and other devices and because of the difficulty fabricating them by other means. The simplest technique involves pressing a mixture of magnetic powder and a binder into a DXRL-formed mold. In the second technique, powder is pressed into the mold and then sintered to densify. The other two processes involve pressing at high temperature either powder or a dense bulk material into a ceramic mold that was previously made using a DXRL mold. These techniques allow arbitrary 2-dimensional shapes to be made 10 to 1000 micrometers thick with in-plane dimensions as small as 50 micrometers and dimensional tolerances in the micron range. Bonded isotropic Nd{sub 2}Fe{sub 14}B micromagnets made by these processes had an energy product of 7 MGOe.
Date: January 7, 1999
Creator: Christenson, T.; Garino, T.J. & Venturini, E.
Partner: UNT Libraries Government Documents Department

Resolution of the nuclear criticality safety issue for the Hanford site high-level waste tanks

Description: This paper describes the approach used to resolve the Nuclear Criticality Safety Issue for the Hanford Site high-level waste tanks. Although operational controls have been in place at the Hanford Site throughout its operating life to minimize the amount of fissile material discarded as waste, estimates of the total amount of plutonium that entered the waste tanks range from 500 to 1,000 kg. Nuclear criticality safety concerns were heightened in 1991 based on a review of waste analysis results and a subsequent U.S. Department of Energy 1399 review of the nuclear criticality program. Although the DOE review team concluded that there was no imminent risk of a criticality at the Hanford Site tank farms, the team also stated its concern regarding the lack of definitive knowledge of the fissile material inventory and distribution within the waste tanks and the lack of sufficient management support for the overall criticality safety program. An in-depth technical review of the nuclear criticality safety of the waste tanks was conducted to develop a defensible technical basis to ensure that waste tanks are subcritical. The review covered all relevant aspects of nuclear criticality safety including neutronics and chemical and physical phenomena of the waste form under aging waste conditions as well as during routine waste management operations. This paper provides a review of the technical basis to support the conclusion that given current plutonium inventories and operating conditions, a nuclear criticality is incredible. The DOE has been requested to close the Nuclear Criticality Safety Issue. The Defense Nuclear Facilities Safety Board is currently reviewing the technicalbasis.
Date: January 7, 1997
Creator: Bratzel, D.R.
Partner: UNT Libraries Government Documents Department

Tank 241-T-201, core 192 analytical results for the final report

Description: This document is the final laboratory report for Tank 241-T-201. Push mode core segments were removed from Riser 3 between April 24, 1997, and April 25, 1997. Segments were received and extruded at 222-S Laboratory. Analyses were performed in accordance with Tank 241-T-201 Push Mode Core Sampling and Analysis Plan (TSAP) (Hu, 1997), Letter of Instruction for Core Sample Analysis of Tanks 241-T-201, 241-T-202, 241-T-203, and 241-T-204 (LOI) (Bell, 1997), Additional Core Composite Sample from Drainable Liquid Samples for Tank 241-T-2 01 (ACC) (Hall, 1997), and Safety Screening Data Quality Objective (DQO) (Dukelow, et al., 1995). None of the subsamples submitted for total alpha activity (AT) or differential scanning calorimetry (DSC) analyses exceeded the notification limits stated in DQO. The statistical results of the 95% confidence interval on the mean calculations are provided by the Tank Waste Remediation Systems Technical Basis Group, and are not considered in this report.
Date: August 7, 1997
Creator: Nuzum, J.L.
Partner: UNT Libraries Government Documents Department

DOE final report, phase one startup, Waste Receiving and Processing Facility (WRAP)

Description: This document is to validate that the WRAP facility is physically ready to start up phase 1, and that the managers and operators are prepared to safely manage and operate the facility when all pre-start findings have been satisfactorily corrected. The DOE Readiness Assessment (RA) team spent a week on-site at Waste Receiving and Processing Module 1 (WRAP-1) to validate the readiness for phase 1 start up of facility. The Contractor and DOE staff were exceptionally cooperative and contributed significantly to the overall success of the RA. The procedures and Conduct of Operations areas had significant discrepancies, many of which should have been found by the contractor review team. In addition the findings of the contractor review team should have led the WRAP-1 management team to correcting the root causes of the findings prior to the DOE RA team review. The findings and observations include many issues that the team believes should have been found by the contractor review and corrective actions taken. A significantly improved Operational Readiness Review (ORR) process and corrective actions of root causes must be fully implemented by the contractor prior to the performance of the contractor ORR for phase 2 operations. The pre-start findings as a result of this independent DOE Readiness Assessment are presented.
Date: January 7, 1998
Creator: Jasen, W.G.
Partner: UNT Libraries Government Documents Department

The Savannah River Site`s groundwater monitoring program: 1990 sampling schedule

Description: This schedule provides a final record of the 1990 sampling schedule for the SRS groundwater monitoring program conducted by the Environmental Protection Department/Environmental Section (EPD/EMS). It includes all the wells monitored by EPD/EMS at SRS during 1990 and identifies the constituents sampled, the sampling frequency, and the reasons for sampling. Sampling requests are incorporated into the schedule throughout the year. Drafts of the schedule are produced and revised quarterly.
Date: February 7, 1991
Creator: Rogers, C.D.
Partner: UNT Libraries Government Documents Department

Parameter identification and on-line estimation for reduced kinetic model

Description: The base hydrolysis process for the destruction of energetic or explosive materials results is a high pH hydrolysate solution with reaction products that include a series of carboxylic acid salts, glycolates, amines, and nitrates. The hydrolysate solutions obtained from this process contain from two to ten wt% of organic carbon and nitrogen compounds that must be further treated before disposal. Hydrothermal oxidation at elevated temperatures (450 C) and pressure (14,000 psi) was selected as the treatment process for the hydrolysate solutions obtained from hydrolysis of the high explosive PBX 9404 at the Department of Energy Pantex facility in Amarillo, Texas. In this work, the authors describe the use of receding horizon identification and estimation techniques to determine the model parameters for a reduced kinetic model describing the oxidation-reduction reactions in a hydrothermal oxidation reactor. This model is used in a model predictive controller that minimizes the total aqueous nitrogen in the hydrothermal oxidation reactor effluent.
Date: August 7, 1998
Creator: Littel, J.D.; Muske, K.R.; Del`Orco, P.C.; Le, L.A. & Flesner, R.L.
Partner: UNT Libraries Government Documents Department

Project W-320, 241-C-106 sluicing HVAC calculations, Volume 1

Description: This supporting document has been prepared to make the FDNW calculations for Project W-320, readily retrievable. The report contains the following calculations: Exhaust airflow sizing for Tank 241-C-106; Equipment sizing and selection recirculation fan; Sizing high efficiency mist eliminator; Sizing electric heating coil; Equipment sizing and selection of recirculation condenser; Chiller skid system sizing and selection; High efficiency metal filter shielding input and flushing frequency; and Exhaust skid stack sizing and fan sizing.
Date: August 7, 1998
Creator: Bailey, J.W.
Partner: UNT Libraries Government Documents Department

Cosmic Closure: Relating the Ultimate Fate of Massive Stars and the Ultimate Fate of the Universe

Description: We give a brief overview of the status of core collapse supernova modeling, particularly as it pertains to predictions of neutrino signatures for the next galactic or near extragalactic supernova. We also consider the implications of neutrino mass for both the supernova mechanism and neutrino signature predictions.
Date: September 7, 1998
Creator: Bruenn, S.W. & Mezzacappa, A.
Partner: UNT Libraries Government Documents Department

Recent Progress on the Standardized DOE Spent Nuclear Fuel Canister

Description: The Department of Energy (DOE) has developed a set of containers for the handling, interim storage, transportation, and disposal in the national repository of DOE spent nuclear fuel (SNF). This container design, referred to as the standardized DOE SNF canister or standardized canister, was developed by the Department's National Spent Nuclear Fuel Storage Program (NSNFP) working in conjunction with the Office of Civilian Radioactive Waste Management (OCRWM) and the DOE spent fuel sites. This canister had to have a standardized design yet be capable of accepting virtually all of the DOE SNF, be placed in a variety of storage and transportation systems, and still be acceptable to the repository. Since specific design details regarding the storage, transportation, and repository disposal of DOE SNF were not finalized, the NSNFP recognized the necessity to specify a complete DOE SNF canister design. This allowed other evaluations of canister performance and design to proceed as well as providing standardized canister users adequate information to proceed with their work. This paper is an update of a paper presented to the 1999 American Nuclear Society of Mechanical Engineers (ASME) Pressure Vessels and Piping (PVP) Conference. It discusses recent progress achieved in various areas to enhance acceptance of this canister not only by the DOE complex but also fabricators and regulatory agencies.
Date: May 7, 2002
Creator: Morton, D.K.; Snow, S.D.; Rahl, T.E.; Hill, T.J. (INEEL) & Morissette, R.P. (Beckman and Associates, Inc.)
Partner: UNT Libraries Government Documents Department

Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands

Description: Improved prediction of interwell reservoir heterogeneity was needed to increase productivity and to reduce recovery cost for California's heavy oil sands, which contain approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley. This investigation involved application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation.
Date: February 7, 2003
Creator: Castle, James W.; Molz, Fred J.; Brame, Scott & Current, Caitlin J.
Partner: UNT Libraries Government Documents Department


Description: During this past six months we continued our ongoing studies of the diffusion controlled uptake of coal and petroleum asphaltenes into a porous carbon catalyst. Toluene was used as the solvent for experiments at 20 C and 75 C while 1-methylnaphthalene was the solvent for the higher temperature experiments at 100 C, 150 C and 250 C. All runs were made at a pressure of 250 psi (inert He gas). Experiments were performed at 20 C and 75 C, for the petroleum asphaltene/toluene system. For the coal asphaltene/toluene system, experiments were performed at 75 C. Experiments were performed at 100 C, 150 C and 250 C for the coal asphaltene/1-methylnaphthalene system. A comparison between the experimental data and model simulated data showed that the mathematical model satisfactorily fitted the adsorptive diffusion of both the coal and petroleum asphaltenes onto a porous activated carbon. The adsorption constant decreases with an increase in temperature for both, the coal asphaltene/1-methylnaphthalene system as well as the petroleum asphaltene/toluene system. It was found that the adsorption constant for the coal asphaltene/toluene system at 75 C was much higher than that of the petroleum asphaltene/toluene system at the same temperature providing evidence of the greater affinity of the coal asphaltenes for the carbon surface. This could be due to the presence of more functional heteroatomic groups in the coal asphaltenes compared to their petroleum counterparts. Also during this time period, a new carbon catalyst support was prepared in our laboratory which will be used in adsorption experiments during the next phase of work.
Date: April 7, 2000
Creator: Guin, James A.; Ramakrishnan, Ganesh & Asada, Keiji
Partner: UNT Libraries Government Documents Department

Phase Startup Initiative Phases 3 and 4 Test Plan and Test Specification ( OCRWM)

Description: Construction for the Spent Nuclear Fuel (SNF) Project facilities is continuing per the Level III Baseline Schedule, and installation of the Fuel Retrieval System (FRS) and Integrated Water Treatment System (IWTS) in K West Basin is now complete. In order to accelerate the project, a phased start up strategy to initiate testing of the FRS and IWTS early in the overall project schedule was proposed (Williams 1999). Wilkinson (1999) expands the definition of the original proposal into four functional testing phases of the Phased Startup Initiative (PSI). Phases 1 and 2 are based on performing functional tests using dummy fuel. This test plan provides overall guidance for Phase 3 and 4 tests, which are performed using actual irradiated N fuel assemblies. The overall objective of the Phase 3 and 4 testing is to verify how the FRS and IWTS respond while processing actual fuel. Conducting these tests early in the project schedule will allow identification and resolution of equipment and process problems before they become activities on the start-up critical path. The specific objectives of this test plan are to: Define the Phase 3 and 4 test scope for the FRS and IWTS; Provide detailed test requirements that can be used to write the specific test procedures; Define data required and measurements to be taken. Where existing methods to obtain these do not exist, enough detail will be provided to define required additional equipment; and Define specific test objectives and acceptance criteria.
Date: August 7, 2000
Partner: UNT Libraries Government Documents Department