States

Snap Shield Test Experiment Reactor Physics Tests (open access)

Snap Shield Test Experiment Reactor Physics Tests

The initial physics tests on the Shield Test Experiment reactor and the precriticality rod-drop test data are presented. (auth)
Date: July 15, 1962
Creator: Tomlinson, R. L.; Johnson, R. P. & Wogulis, S. G.
Object Type: Report
System: The UNT Digital Library
Is the two-term expansion valid for highly anisotropic systems. The Townsend ionization coefficient in strong runaway as a test case (open access)

Is the two-term expansion valid for highly anisotropic systems. The Townsend ionization coefficient in strong runaway as a test case

The Townsend ionization coefficient in the strong runaway regime is calculated within the framework of the two-term expansion. Results are compared to the 1-D model. General features of the two models are qualitatively similar, but quantitative differences by factors of approx. 2 are observed.
Date: July 15, 1982
Creator: Yu, S. S. & Melendez, R. E.
Object Type: Report
System: The UNT Digital Library
Kilowatt Isotope Power System: component test procedure for the ground demonstration system jet condenser focusing. 77-KIPS-59 (open access)

Kilowatt Isotope Power System: component test procedure for the ground demonstration system jet condenser focusing. 77-KIPS-59

This test procedure (No. 404) provides a detailed description of the verification methods which shall be used in the development program to be conducted on the Kilowatt Isotope Power System (KIPS) Jet Condenser to fulfill the requirements of the Ground Demonstration Test Plan, Section 6.4.
Date: July 15, 1977
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Beam and viewing dump positioning inside TFTR for CTS alpha-particle diagnostics (open access)

Beam and viewing dump positioning inside TFTR for CTS alpha-particle diagnostics

A collective Thomson scattering (CTS) diagnostic system for localized measurement of energetic ions is being developed for TFTR. This system will use a 200KW, 56GHz gyrotron and a sensitive heterodyne receiver. In addition, a key element of this system will be beam and viewing dumps which are needed to minimize detection of stray gyrotron and ECE background radiation by the receiver system. It is the purpose of this study to determine the size and location of these dumps inside TFTR taking into account beam refraction and launch and receiver antenna optics scanning. The beam dump must cover all the area in the vacuum chamber where the beam is expected to impinge, and the viewing dump must cover all the areas within the direct line of sight of the receiver antenna. The beam launch system and the receiver antenna are to be placed nearly symmetrically above and below the midplane of the tokamak vacuum vessel, respectively. The beam dump is to be placed at the bottom inside of the vacuum vessel to absorb the gyrotron beam which will be launched from a top port. The viewing dump is expected to be placed symmetrically at the top inside of the vacuum vessel, …
Date: July 15, 1991
Creator: Rhee, D.Y.; Woskov, P.P. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center); Ellis, R. & Park, H. (Princeton Univ., NJ (United States). Plasma Physics Lab.)
Object Type: Report
System: The UNT Digital Library
Introduction to nuclear test engineering (open access)

Introduction to nuclear test engineering

The basic information in this report is from a vu-graph presentation prepared to acquaint new or prospective employees with the Nuclear Test Engineering Division (NTED). Additional information has been added here to enhance a reader's understanding when reviewing the material after hearing the presentation, or in lieu of attending a presentation.
Date: July 15, 1982
Creator: O'Neal, W.C. & Paquette, D.L.
Object Type: Report
System: The UNT Digital Library
Hyperfine Structure of the Electronic Ground States of Rb$sup 85$ And Rb$sup 8$$sup 7$ (open access)

Hyperfine Structure of the Electronic Ground States of Rb$sup 85$ And Rb$sup 8$$sup 7$

None
Date: July 15, 1962
Creator: Penselin, S.; Moran, T.; Cohen, V.W. & Winkler, G.
Object Type: Article
System: The UNT Digital Library
Studies of human mutation rates (open access)

Studies of human mutation rates

The three objectives of the program are: To isolate by the technique of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), proteins of special interest because of the relative mutability of the corresponding gene, establish the identity of the protein, and, for selected proteins, move to a characterization of the corresponding gene; To develop a more efficient approach, based on 2-D PAGE, for the detection of variants in DNA, with special reference to the identification of a variant in a child not present in either parent of the child (i.e., a mutation); and, To continue an effective interface with the genetic studies on the children of atomic bomb survivors in Japan, with reference to both the planning and implementation of new studies at the molecular level. For administrative purposes, the program is subdivided into four sections, each under the direction of one of the four co-PIs; the progress during the past year will be summarized in accordance with this sectional structure. 1 tab.
Date: July 15, 1991
Creator: Neel, J.V.
Object Type: Report
System: The UNT Digital Library
FABRICATION OF CERAMIC INTERNAL REFLECTOR FOR THE SNAP 8 EXPERIMENTAL REACTOR (open access)

FABRICATION OF CERAMIC INTERNAL REFLECTOR FOR THE SNAP 8 EXPERIMENTAL REACTOR

Fabrication of internal reflector pieces for the SNAP-8 core is described. These reflectors were made of BeO, with and without the addition of Sm/sub 2/O/sub 3/ as a nuclear poison. Because of the high density and dimensional tolerance requirements, the complexity of shapes, and the comparatively modest number of parts to be produced (approximately 1000), the blanks were hot pressed and subsequently machined with diamond wheels and cores. In almost all cases, the specified density of 98% of theoretical was achieved. The low eutectic temperature in the BeO--Sm/sub 2/O/sub 3/ system of about 1420 deg C necessitated special pressing parameters, which were arrived at by experimentation. A rather coarse grit size (80) was used for the diamond wheels, which resulted in very little wear to the wheels, and an extremely low dimensional rejection rate on the blanks. Because of the toxicity of BeO, all equipment was enclosed, and was held under negative pressure. (auth)
Date: July 15, 1962
Creator: Langrod, K.
Object Type: Report
System: The UNT Digital Library
Utilization of coal associated minerals. Quarterly report No. 10, January 1-March 31, 1980 (open access)

Utilization of coal associated minerals. Quarterly report No. 10, January 1-March 31, 1980

In the preceding quarterly report, it was reported that while sampling the Solvent Refined Coal II (SRC II) pilot plant at Fort Lewis, Washington, the plant went down and vacuum bottoms waste material representing the minerals flow at the last steady state condition were obtained. This plant has been sampled again and samples of the incoming feed coal, sized coal and vacuum bottoms waste material were obtained. As part of our effort to trace the same mineral suite through mining, preparation and conversion, new samples of feed coal, cleaned coal and refuse were obtained from the District 4 commercial preparation plant. This preparation plant supplies coal to the SRC II pilot plant at Fort Lewis, Washington. A study of the thermal insulating properties of fired flyash based structural materials was completed and is included.
Date: July 15, 1980
Creator: Slonaker, J. F.; Buttermore, W. H.; Carlisle, J. A.; Durham, D. L.; Muter, R. B. & Alderman, J. K.
Object Type: Report
System: The UNT Digital Library
Structural and electronic studies of defects in amorphous silicon. Technical progress report, March-May 1980 (open access)

Structural and electronic studies of defects in amorphous silicon. Technical progress report, March-May 1980

Proton magnetic resonance data are presented for plasma-deposited amorphous Si:H as a function of annealing temperature up to 650/sup 0/C. The data indicate that hydrogen diffuses internally before major evolution occurs, that transfer of hydrogen occurs from a heavily clustered phase to a dilute phase coincident with evolution and that evolution occurs initially from the heavily clustered phase. Comparison with infrared data indicates that the heavily clustered phase can be either SiH/ sub x/t = 2,3) or SiH.
Date: July 15, 1980
Creator: Street, R. A.
Object Type: Report
System: The UNT Digital Library
Bioethical perspective on acceptable-risk criteria for nuclear-waste management (open access)

Bioethical perspective on acceptable-risk criteria for nuclear-waste management

Wisely managing the profound human and environmental risks of nuclear wastes requires complex moral and ethical judgments. Whereas traditional ethics is limited to interpersonal relations, a new system of ethics--bioethics--concerns man's relation with nature. Environmentalists claim that technology has upset the balance of nature, that nature is sacred and has inviolable rights, and that man must therefore regulate his behavior to conform to earth's limited carrying capacity. They also say that Judeo-Christian monotheism and anthropocentrism have sanctioned the exploitation of nature in the West, whereas Eastern religions teach adaptation to nature. Evidence suggests, however, that the balance of nature is neither absolute nor precarious, but is continually changing. Moreover, technology has brought more good than harm to man, and man's needs should supersede nature's. Other evidence indicates that the earth's resources may be neither limited nor nearly exhausted. Persuasive arguments also demonstrate that man's relation with nature is not traceable to religious assumptions. In assessing the risks/benefits of nuclear-waste management, we should avoid risks that jeopardize the rights of future generations without imposing excessive sacrifices on the present generation.
Date: July 15, 1977
Creator: Maxey, M.N.
Object Type: Report
System: The UNT Digital Library
Development and function of membrane systems in plant tissue. Annual progress report, 15 July 1974--14 July 1975. [Ion transport in corn roots] (open access)

Development and function of membrane systems in plant tissue. Annual progress report, 15 July 1974--14 July 1975. [Ion transport in corn roots]

None
Date: July 15, 1975
Creator: Arntzen, C.J.
Object Type: Report
System: The UNT Digital Library
The U5. 0 Undulator for the ALS (open access)

The U5. 0 Undulator for the ALS

the U5.0 Undulator, and 89 period, 5 cm period length, 4.6 m long insertion device has been designed, is being fabricated and is scheduled for completion in early 1992. This undulator will be the first high brightness source, in the 50 to 1500 eV range, for the Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory. A hybrid magnetic configuration using Nd-Fe-B permanent magnet material and vanadium permendur poles has been selected to achieve the field quality needed to meet performance requirements. The magnetic structure is modular with each half consisting of 5 assembly sections, which provide the periodic structure, and end structures, for entrance and exit correction, mounted on a steel backing beam. Each assembly section consists of 35 half-period pole assemblies bolted to a mount. The required 0.837 Tesla effective peak field at a 1.4 cm gap has been verified with model measurements. Vertical field integral correction is accomplished with the end structures, each having an arrangement of permanent magnet rotors which will be adjusted to minimize electron beam missteering over the undulator operating field range. To reduce the effect of environmental fields, the steel backing beams are connected through parallel, low-reluctance, Ni-Fe hinges. The magnetic structure is …
Date: July 15, 1991
Creator: Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W.V.; Humphries, D.; Kincaid, B. et al.
Object Type: Article
System: The UNT Digital Library
Space propulsion by fusion in a magnetic dipole (open access)

Space propulsion by fusion in a magnetic dipole

The unique advantages of fusion rocket propulsion systems for distant missions are explored using the magnetic dipole configurations as an example. The dipole is found to have features well suited to space applications. Parameters are presented for a system producing a specific power of kW/kg, capable of interplanetary flights to Mars in 90 days and to Jupiter in a year, and of extra-solar-system flights to 1000 astronomical units (the Tau mission) in 20 years. This is about 10 times better specific power performance than nuclear electric fission systems. Possibilities to further increase the specific power toward 10 kW/kg are discussed, as is an approach to implementing the concept through proof-testing on the moon. 20 refs., 14 figs., 2 tabs.
Date: July 15, 1991
Creator: Teller, E.; Glass, A.J.; Fowler, T.K. (Lawrence Livermore National Lab., CA (United States)); Hasegawa, A. (AT and T Bell Labs., Murray Hill, NJ (United States)) & Santarius, J.F. (Wisconsin Univ., Madison, WI (United States). Fusion Technology Inst.)
Object Type: Article
System: The UNT Digital Library
Raman sidescatter instability in a nonuniform plasma (open access)

Raman sidescatter instability in a nonuniform plasma

In the various laser-fusion concepts, an intense electromagnetic wave (the laser) must propagate through an underdense plasma region where it could decay, via the stimulated Raman instability, into a Langmuir plasma wave and a scattered electromagnetic wave. Results are obtained by evaluating the ''Green's function'' response in time and space for the scattered electromagnetic waves assuming they are initiated by a ''delta-function'' source. We consider the case where the temporal growth dominates the plasma wave convection. Then the scattered electromagnetic waves are governed by a single second-order Helmholtz differential equation, in the position variable along the density gradient, with a complex potential having two simple zeros (turning points) and one simple pole.
Date: July 15, 1977
Creator: Mostrom, M.A.
Object Type: Report
System: The UNT Digital Library
Value/impact of design criteria for cast ductile iron shipping casks (open access)

Value/impact of design criteria for cast ductile iron shipping casks

The ductile failure criteria proposed in the Base report appear appropriate except that stress intensity values, S/sub m/ should be based on lower safety factors and ductility should be added as a criterion. A safety factor for stress intensity, s/sub m/ of 4 is recommended rather than 3 on minimum ultimate tensile strength, S/sub u/ in accordance with ASME code philosophy of assigning higher safety factors to cast ductile iron than to steel. This more conservative approach has no impact on costs since the selection of wall thickness is controlled by shielding rather than by stress considerations. The addition of a ductility criterion is recommended because of the problems associated with the selection of appropriate brittle failure criteria and the potential for cast ductile iron to have extremely low elongation at failure. Neither a materials nor a linear elastic fracture mechanics (LEFM) approach appear to be viable for demonstrating the prevention of brittle failure in cast ductile iron shipping casks. It is possible that the analytic methods predict brittle failure because of extremely conservative assumptions whereas real casks may not fail. Model drop tests could be used to demonstrate containment integrity. It is estimated that a risk committment of at …
Date: July 15, 1983
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Improved Approach to Characterizing and Presenting Streak Camera Performance (open access)

Improved Approach to Characterizing and Presenting Streak Camera Performance

The performance of a streak camera recording system is strongly linked to the technique used to amplify, detect and quantify the streaked image. At the Lawrence Livermore National Laboratory (LLNL) streak camera images have been recorded both on film and by fiber-optically coupling to charge-coupled devices (CCD's). During the development of a new process for recording these images (lens coupling the image onto a cooled CCD) the definitions of important performance characteristics such as resolution and dynamic range were re-examined. As a result of this development, these performance characteristics are now presented to the streak camera user in a more useful format than in the past. This paper describes how these techniques are used within the Laser Fusion Program at LLNL. The system resolution is presented as a modulation transfer function, including the seldom reported effects that flare and light scattering have at low spatial frequencies. Data are presented such that a user can adjust image intensifier gain and pixel averaging to optimize the useful dynamic range in any particular application.
Date: July 15, 1985
Creator: Wiedwald, J. D. & Jones, B. A.
Object Type: Article
System: The UNT Digital Library
An Implicit "Drift-Lorentz" Particle Mover for Plasma and Beam Simulations (open access)

An Implicit "Drift-Lorentz" Particle Mover for Plasma and Beam Simulations

In order to efficiently perform particle simulations in systems with widely varying magnetization, we developed a drift-Lorentz mover, which interpolates between full particle dynamics and drift kinetics in such a way as to preserve a physically correct gyroradius and particle drifts for both large and small ratios of the timestep to the cyclotron period. In order to extend applicability of the mover to systems with plasma frequency exceeding the cyclotron frequency such as one may have with fully neutralized drift compression of a heavy-ion beam we have developed an implicit version of the mover. A first step in this direction, in which the polarization charge was added to the field solver, was described previously. Here we describe a fully implicit algorithm (which is analogous to the direct-implicit method for conventionalparticle-in-cell simulation), summarize a stability analysis of it, and describe several tests of the resultant code.
Date: July 15, 2008
Creator: Friedman, A.; Grote, D. P.; Vay, J. L. & Cohen, R. H.
Object Type: Article
System: The UNT Digital Library
Gravity monitoring of CO2 movement during sequestration: Model studies (open access)

Gravity monitoring of CO2 movement during sequestration: Model studies

We examine the relative merits of gravity measurements as a monitoring tool for geological CO{sub 2} sequestration in three different modeling scenarios. The first is a combined CO{sub 2} enhanced oil recovery (EOR) and sequestration in a producing oil field, the second is sequestration in a brine formation, and the third is for a coalbed methane formation. EOR/sequestration petroleum reservoirs have relatively thin injection intervals with multiple fluid components (oil, hydrocarbon gas, brine, and CO{sub 2}), whereas brine formations usually have much thicker injection intervals and only two components (brine and CO{sub 2}). Coal formations undergoing methane extraction tend to be thin (3-10 m), but shallow compared to either EOR or brine formations. The injection of CO{sub 2} into the oil reservoir produced a bulk density decrease in the reservoir. The spatial pattern of the change in the vertical component of gravity (G{sub z}) is directly correlated with the net change in reservoir density. Furthermore, time-lapse changes in the borehole G{sub z} clearly identified the vertical section of the reservoir where fluid saturations are changing. The CO{sub 2}-brine front, on the order of 1 km within a 20 m thick brine formation at 1900 m depth, with 30% CO{sub 2} …
Date: July 15, 2008
Creator: Gasperikova, E. & Hoversten, G.M.
Object Type: Article
System: The UNT Digital Library
Sampling and Analysis Plan Waste Treatment Plant Seismic Boreholes Project. (open access)

Sampling and Analysis Plan Waste Treatment Plant Seismic Boreholes Project.

This sampling and analysis plan (SAP) describes planned data collection activities for four entry boreholes through the sediment overlying the Saddle Mountains Basalt, up to three new deep rotary boreholes through the Saddle Mountains Basalt and sedimentary interbeds, and one corehole through the Saddle Mountains Basalt and sedimentary interbeds at the Waste Treatment Plant (WTP) site. The SAP will be used in concert with the quality assurance plan for the project to guide the procedure development and data collection activities needed to support borehole drilling, geophysical measurements, and sampling. This SAP identifies the American Society of Testing Materials standards, Hanford Site procedures, and other guidance to be followed for data collection activities. Revision 3 incorporates all interim change notices (ICN) that were issued to Revision 2 prior to completion of sampling and analysis activities for the WTP Seismic Boreholes Project. This revision also incorporates changes to the exact number of samples submitted for dynamic testing as directed by the U.S. Army Corps of Engineers. Revision 3 represents the final version of the SAP.
Date: July 15, 2007
Creator: Brouns, Thomas M.
Object Type: Report
System: The UNT Digital Library
UXO detection and identification based on intrinsic target polarizabilities: A case history (open access)

UXO detection and identification based on intrinsic target polarizabilities: A case history

Electromagnetic induction data parameterized in time dependent object intrinsic polarizabilities allow discrimination of unexploded ordnance (UXO) from false targets (scrap metal). Data from a cart-mounted system designed for discrimination of UXO with 20 mm to 155 mm diameters are used. Discrimination of UXO from irregular scrap metal is based on the principal dipole polarizabilities of a target. A near-intact UXO displays a single major polarizability coincident with the long axis of the object and two equal smaller transverse polarizabilities, whereas metal scraps have distinct polarizability signatures that rarely mimic those of elongated symmetric bodies. Based on a training data set of known targets, object identification was made by estimating the probability that an object is a single UXO. Our test survey took place on a military base where both 4.2-inch mortar shells and scrap metal were present. The results show that we detected and discriminated correctly all 4.2-inch mortars, and in that process we added 7%, and 17%, respectively, of dry holes (digging scrap) to the total number of excavations in two different survey modes. We also demonstrated a mode of operation that might be more cost effective than the current practice.
Date: July 15, 2008
Creator: Gasperikova, E.; Smith, J.T.; Morrison, H.F.; Becker, A. & Kappler, K.
Object Type: Article
System: The UNT Digital Library
Characterization of Surplus Plutonium for Disposition Options (open access)

Characterization of Surplus Plutonium for Disposition Options

The United States (U.S.) has identified 61.5 metric tons (MT) of plutonium that is permanently excess to use in nuclear weapons programs, including 47.2 MT of weapons-grade plutonium. Except for materials that remain in use for programs outside of national defense, including programs for nuclear-energy development, the surplus inventories will be stored safely by the Department of Energy (DOE) and then transferred to facilities that will prepare the plutonium for permanent disposition. Some items will be disposed as transuranic waste, low-level waste, or spent fuel. The remaining surplus plutonium will be managed through: (1) the Mixed Oxide (MOX) Fuel Fabrication Facility (FFF), to be constructed at the Savannah River Site (SRS), where the plutonium will be converted to fuel that will be irradiated in civilian power reactors and later disposed to a high-level waste (HLW) repository as spent fuel; (2) the SRS H-Area facilities, by dissolving and transfer to HLW systems, also for disposal to the repository; or (3) alternative immobilization techniques that would provide durable and secure disposal. From the beginning of the U.S. program for surplus plutonium disposition, DOE has sponsored research to characterize the surplus materials and to judge their suitability for planned disposition options. Because many …
Date: July 15, 2008
Creator: Allender, Jeffrey S.; Moore, Edwin N. & Davies, Scott H.
Object Type: Article
System: The UNT Digital Library
A Semi-Analytical Solution for Large-Scale Injection-Induced PressurePerturbation and Leakage in a Laterally Bounded Aquifer-AquitardSystem (open access)

A Semi-Analytical Solution for Large-Scale Injection-Induced PressurePerturbation and Leakage in a Laterally Bounded Aquifer-AquitardSystem

A number of (semi-)analytical solutions are available to drawdown analysis and leakage estimation of shallow aquifer-aquitard systems. These solutions assume that the systems are laterally infinite. When a large-scale pumping from (or injection into) an aquifer-aquitard system of lower specific storativity occurs, induced pressure perturbation (or hydraulic head drawdown/rise) may reach the lateral boundary of the aquifer. We developed semi-analytical solutions to address the induced pressure perturbation and vertical leakage in a 'laterally bounded' system consisting of an aquifer and an overlying/underlying aquitard. A one-dimensional radial flow equation for the aquifer was coupled with a one-dimensional vertical flow equation for the aquitard, with a no-flow condition imposed on the outer radial boundary. Analytical solutions were obtained for (1) the Laplace-transform hydraulic head drawdown/rise in the aquifer and in the aquitard, (2) the Laplace-transform rate and volume of leakage through the aquifer-aquitard interface integrated up to an arbitrary radial distance, (3) the transformed total leakage rate and volume for the entire interface, and (4) the transformed horizontal flux at any radius. The total leakage rate and volume depend only on the hydrogeologic properties and thicknesses of the aquifer and aquitard, as well as the duration of pumping or injection. It was …
Date: July 15, 2008
Creator: Zhou, Quanlin; Birkholzer, Jens T. & Tsang, Chin-Fu
Object Type: Article
System: The UNT Digital Library
Aftertreatment Technologies for Off-Highway Heavy-Duty Diesel Engines (open access)

Aftertreatment Technologies for Off-Highway Heavy-Duty Diesel Engines

The objective of this program was to explore a combination of advanced injection control and urea-selective catalytic reduction (SCR) to reduce the emissions of oxides of nitrogen (NOx) and particulate matter (PM) from a Tier 2 off-highway diesel engine to Tier 3 emission targets while maintaining fuel efficiency. The engine used in this investigation was a 2004 4.5L John Deere PowerTechTM; this engine was not equipped with exhaust gas recirculation (EGR). Under the original CRADA, the principal objective was to assess whether Tier 3 PM emission targets could be met solely by increasing the rail pressure. Although high rail pressure will lower the total PM emissions, it has a contrary effect to raise NOx emissions. To address this effect, a urea-SCR system was used to determine whether the enhanced NOx levels, associated with high rail pressure, could be reduced to Tier 3 levels. A key attraction for this approach is that it eliminates the need for a Diesel particulate filter (DPF) to remove PM emissions. The original CRADA effort was also performed using No.2 Diesel fuel having a maximum sulfur level of 500 ppm. After a few years, the CRADA scope was expanded to include exploration of advanced injection strategies …
Date: July 15, 2008
Creator: Kass, M.D.
Object Type: Report
System: The UNT Digital Library