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Absorption corrections for x-ray fluorescence analysis of environmental samples (open access)

Absorption corrections for x-ray fluorescence analysis of environmental samples

The discovery of a very simple and useful relationship between the absorption coefficient of a particular element and the ratio of incoherent to coherent scattering by the sample containing the element is discussed. By measuring the absorption coefficients for a few elements in a few samples, absorption coefficients for many elements in an entire set of similar samples can be obtained. (auth)
Date: August 29, 1975
Creator: Bazan, F. & Bonner, N. A.
System: The UNT Digital Library
Coil winder for the magnet of the mirror fusion test facility (open access)

Coil winder for the magnet of the mirror fusion test facility

A coil winder was designed for the purpose of fabricating the superconducting magnets of the Mirror Fusion Test Facility. The superconducting magnets are a displaced ying-yang pair, each having major and minor radii of 2.5 and 0.75 m, respectively, and cross section of 0.42 m by about 1.03 m. The superconductor cross section is a square, 13 mm on a side, and consists of a core of niobium-titanium embedded copper and a solid copper stabilizer. Conceptual studies made at Lawrence Livermore Laboratory of the coil winder resulted in concept drawings and a procurement specification. Final design was made by the contractor, and the coil winder is now in fabrication. This paper describes the performance requirements of the winder, and the evolution of its design from conceptual stage to completion.
Date: August 29, 1977
Creator: Ling, R.C.
System: The UNT Digital Library
Samanid ceramics and neutron activation analysis (open access)

Samanid ceramics and neutron activation analysis

Glazed pottery known as ''Afrasiyab'' and ''Nishapur'' wares (early Islamic ceramics) are generally attributed to the Samanid dynasty (819-1005). The clay composition of Samanid wares and discarded kiln items found in situ were analyzed by NAA and the elemental composition compared with that of other sherds. 7 figures, 1 table. (DLC)
Date: August 29, 1977
Creator: Azarpay, G.; Frierman, J.D. & Asaro, F.
System: The UNT Digital Library
Tormac experimental apparatus (open access)

Tormac experimental apparatus

A brief review of the Tormac program is given. The Tormac IV, Tormac V, and puffer experiments are mentioned. (MOW)
Date: August 29, 1978
Creator: Levine, M. A. & Myers, B. R.
System: The UNT Digital Library
Microprocessor-controlled portable neutron spectrometer (open access)

Microprocessor-controlled portable neutron spectrometer

A neutron spectrometer that acquires and unfolds data in the field has been developed for use in the energy range from 1 to 20 MeV. The system includes an NE213 organic scintillation detector, automatic gain stabilization, automatically stabilized pulseshape discrimination, an LSl-11 microprocessor for control and data reduction, and a multichannel analyzer for data acquisition. The system, with the exception of the multichannel analyzer, is mounted in a suitcase 47 by 66 by 23.5 cm. The mass is 23.5 kg.
Date: August 29, 1979
Creator: Hunt, G. F.; Kaifer, R. C.; Slaughter, D. R.; Strout, R. E., II & Rueppel, D. W.
System: The UNT Digital Library
Charged-particle coating (open access)

Charged-particle coating

Advanced target designs require thicker (approx. 300 ..mu..m) coatings and better surface finishes that can be produced with current coating techniques. An advanced coating technique is proposed to provide maximum control of the coating flux and optimum manipulation of the shell during processing. In this scheme a small beam of ions or particles of known incident energy are collided with a levitated spherical mandrel. Precise control of the incident energy and angle of the deposition flux optimizes the control of the coating morphology while controlled rotation and noncontact support of the shell minimizes the possibility of particulate or damage generated defects. Almost infinite variability of the incident energy and material in this process provides increased flexibility of the target designs which can be physically realized.
Date: August 29, 1980
Creator: Johnson, W. L.; Crane, J. K. & Hendricks, C. D.
System: The UNT Digital Library
Effect of non-heterogeneous wetwell boundaries on pressure suppression system response. [BWR] (open access)

Effect of non-heterogeneous wetwell boundaries on pressure suppression system response. [BWR]

The Full-Scale Mark II CRT (Containment Response Test) Program is in progress at the Tokai-Mura Establishment of the Japan Atomic Energy Research Institute (JAERI). The primary objective of the on-going CRT Program is to provide a data base for evaluation of the pressure suppression pool (wetwell) hydrodynamic loads associated with a postulated loss-of-coolant accident (LOCA) in the BWR Mark II containment system. The test facility is 1/18 of full scale in volume and has a wetwell which is a full-scale geometric replica of one 20/sup 0/-sector of a reference 1100MWe Mark II.
Date: August 29, 1980
Creator: McCauley, E.W.; Holman, G.S.; Namatame, K.; Kukita, Y. & Shiba, M.
System: The UNT Digital Library
Recent advances in Pt coating of microspheres by a batch magnetron sputtering process (open access)

Recent advances in Pt coating of microspheres by a batch magnetron sputtering process

Some proposed inertial confinement fusion targets require high-Z, high density metal coatings on glass microspheres. Platinum, which satisfies the high-Z and density requirements, can be coated onto microspheres with a batch magnetron sputtering process incorporating oxygen as a dopant gas to prevent the microspheres from sticking. This paper outlines recent progress in three areas: First, the coating process has been improved; second, the oxygen content and resistivity of the oxygen doped platinum films are analyzed; and third, the roles oxygen may play in reducing microsphere sticking during sputtering are discussed in regard to cold welding, Van der Waals bonding, electrostatic sticking, and sintering.
Date: August 29, 1980
Creator: Hsieh, E. J. & Meyer, S. F.
System: The UNT Digital Library
Ion microstability in tandem mirrors (open access)

Ion microstability in tandem mirrors

The formalism describing ion-cyclotron modes in mirror traps will be developed. Emphasis will be placed on the effects of finite axial boundaries on the normal modes of the system. Wave properties are a composite picture of: positive energy waves (plasma oscillation, shear Alfven and drift waves), negative energy waves (ion Bernstein waves in a loss-cone media), positive dissipation (electron Landau damping, outgoing waves), and negative dissipation (ion cyclotron damping in a loss-cone and anisotropic temperature medium). Stability boundaries in this bounded media is affected by scale lengths along the magnetic field; first, because they determine the widths of the resonances, and second, because they restrict the parallel structure of the modes.
Date: August 29, 1983
Creator: Pearlstein, L.D.
System: The UNT Digital Library
Thermal barriers: their purpose and functioning (open access)

Thermal barriers: their purpose and functioning

This review covers the following topics: (1) thermal barrier formation, (2) ion pumping, (3) high-field throttle coil, and (4) microstability. (MOW)
Date: August 29, 1983
Creator: Baldwin, D.E.
System: The UNT Digital Library
Three-dimensional equilibrium in quadrupole symmetric tandem mirrors in the paraxial limit (reduced MHD) (open access)

Three-dimensional equilibrium in quadrupole symmetric tandem mirrors in the paraxial limit (reduced MHD)

Equilibrium in quadrupole symmetric mirrors is fully three dimensional; however, because axial scale lengths are long compared with radial scale lengths (equivalently weak curvature) it is possible to reduce the complexity of the equations by expanding in the appropriate smallness parameter. Such a procedure leads to set of reduced MHD equations. The general theory will be presented, numerical results discussed, modifications due to finite Larmor radius will be added, and an analytic solution for sharp boundary pressure models will be developed.
Date: August 29, 1983
Creator: Pearlstein, L.D.
System: The UNT Digital Library
Absolute dipole gamma-ray strength functions for /sup 176/Lu (open access)

Absolute dipole gamma-ray strength functions for /sup 176/Lu

We have derived absolute dipole strength-function information for /sup 176/Lu from an average resonance capture study of /sup 175/Lu with 2-keV neutrons, and from neutron capture cross-section measurements with neutrons from 30 keV to about 1 MeV. We found that we needed to increase our previous estimate of the relative M1/E1 strengths near 5 MeV by a factor of 3, and to revise downward the absolute magnitude of our E1 strength function. We accomplished the latter, while still maintaining continuity with the photonuclear data, by adjusting the one free parameter in our line shape. The present E1 and M1 strengths now seem correct both near the neutron separation energy and also around 1 MeV.
Date: August 29, 1984
Creator: Gardner, D. G.; Gardner, M. A. & Hoff, R. W.
System: The UNT Digital Library
Isomer ratio calculations using modeled discrete levels (open access)

Isomer ratio calculations using modeled discrete levels

We have calculated isomer ratios for the /sup 175/Lu(n,..gamma..), /sup 175/Lu(n,2n), /sup 237/Np(n,2n), /sup 241/Am(n,..gamma..), and /sup 243/Am(n,..gamma..) reactions using modeled level structures in the deformed, odd-odd product nuclei. We find: that the hundreds of discrete levels and their gamma-ray branching ratios provided by the modeling are necessary to achieve agreement with experiment, that many rotational bands must be included in order to obtain a sufficiently representative selection of K quantum numbers, and that the levels of each band must be extended to appropriately high values of angular momentum. 8 references.
Date: August 29, 1984
Creator: Gardner, M. A.; Gardner, D. G. & Hoff, R. W.
System: The UNT Digital Library
Does the photino decay (open access)

Does the photino decay

The stability of the lightest superpartner is a crucial aspect of many experimental searches for supersymmetry and of supersymmetric dark matter candidates. It is shown that R parity may occur in operators of dimension four or less as an accidental consequence of an exact Z/sub N/ symmetry. In this case the lightest superpartner can decay via higher dimension operators. The lifetime depends on the scale of the new physics responsible for the non-renormalizable operators; it could be anywhere in the region 10/sup -20/ seconds to 10/sup +20/ seconds. Explicit examples are given. 12 refs.
Date: August 29, 1986
Creator: Hall, L.J.
System: The UNT Digital Library
Plasma diagnostic techniques in thermal-barrier tandem-mirror fusion experiments (open access)

Plasma diagnostic techniques in thermal-barrier tandem-mirror fusion experiments

We review two classes of plasma diagnostic techniques used in thermal-barrier tandem-mirror fusion experiments. The emphasis of the first class is to study mirror-trapped electrons at the thermal-barrier location. The focus of the second class is to measure the spatial and temporal behavior of the plasma space potential at various axial locations. The design and operation of the instruments in these two categories are discussed and data that are representative of their performance is presented.
Date: August 29, 1986
Creator: Silver, E. H.; Clauser, J. F.; Carter, M. R.; Failor, B. H.; Foote, J. H.; Hornady, R. S. et al.
System: The UNT Digital Library
Recent progress in heavy-ion fusion in the US (open access)

Recent progress in heavy-ion fusion in the US

Recent developments in accelerator physics and technology have led to lower cost estimates for a heavy-ion induction linac driver. Studies show that the cost of electricity produced using such a driver are competitive with other fusion systems at a plant capacity of 1.2 GW/sub e/ and are competitive with projected fission power costs at less than 4 GW/sub e/.
Date: August 29, 1986
Creator: Bangerter, R.O.
System: The UNT Digital Library
TIBER II configuration and structural design (open access)

TIBER II configuration and structural design

The TIBER-II machine is a minimum-size steady-state tokamak with sufficient fusion power, wall flux, and fluence to be used for undertaking a nuclear test mission. Although the machine is envisioned as an engineering device, it will demonstrate reactor-relevant physics. To achieve the small size and high performance goals of TIBER II, the engineered systems must be based on aggressive assumptions. In addition, the machine must be designed for ease of maintenance to ensure reaching the fluence goal of 5 MW yr/m/sup 2/ in a design lifetime of 13 years. This paper concentrates on the configuration and structural issues of designing a small, high-field, and high-flux device.
Date: August 29, 1986
Creator: Doggett, James N.
System: The UNT Digital Library
Top quark and light Higgs scalar mass bounds in no-scale supergravity (open access)

Top quark and light Higgs scalar mass bounds in no-scale supergravity

No-scale supergravity theories with the minimal low-energy particle content are shown to become untenable for a top quark mass m/sub T/ much less than 40 GeV. For m/sub T/ < 55 GeV, a stringent upper bound operates on the mass of the lowest-lying Higgs scalar. Further, the Higgs pseudoscalar is constrained to be nearly a quarter as massive as the gluino.
Date: August 29, 1986
Creator: Roy, P.
System: The UNT Digital Library
Modified-Yee field solutions in the AMOS wakefield code (open access)

Modified-Yee field solutions in the AMOS wakefield code

A new numerical procedure by which field calculations in AMOS are upgraded to model rotationally symmetric cavity structures in a more accurate fashion is described. The development work is aimed at implementing a modified finite difference update scheme on an irregular grid system. Elements of an irregular grid may be chosen to better fit object boundaries, resulting in increased solution accuracy. Our approach involves the placement of field components on a non-orthogonal body fitting grid and on a dual grid which is orthogonal to the first grid. It is found that this procedure retains several important computational advantages, including the ability to exploit the implied spatial relationships between nodes. Propagating fields on an irregular grid system have been observed and comparisons between finite difference AMOS and Modified-Yee AMOS field calculations are provided.
Date: August 29, 1990
Creator: Shang, C. C. & DeFord, J. F.
System: The UNT Digital Library
Meshes: The next generation (open access)

Meshes: The next generation

Building complex meshes for large-scale numerical simulations presents immense difficulties in exploiting high-performance computers. Industry and research leaders will describe the current state of the art for generating meshes for such large scientific problems. This will be followed by a panel and general audience discussion of the algorithmic and architectural issues surrounding the generation of meshes with10{sup 7} to 10{sup 9} grid points. (Note: The terms ``mesh`` and ``grid`` are used interchangeably in the literature.)
Date: August 29, 1994
Creator: Christon, M.; Hardin, D.; Compton, J. & Zosel, M.
System: The UNT Digital Library
Successful integration of pollution prevention strategies during deactivation and decommissioning of chemistry R{ampersand}D facilities (open access)

Successful integration of pollution prevention strategies during deactivation and decommissioning of chemistry R{ampersand}D facilities

The Chemistry & Materials Sciences (C&MS) Directorate is in the third year of a four-year space consolidation plan. In 1994, approximately half of the total directorate square footage was comprised of 40-year old wet chemistry research buildings that had exceeded their useful life and were viewed a legacy facilities to the program. This mix of old vs. new laboratory space was not properly aligned nor suited for future needs of C&MS, from both the cultural or economic position, thus change was needed. C&MS instituted an aggressive, strategic, business-driven space consolidation initiative, called SAT (Space Action Team), to optimize space utilization, reduce annual costs, meet strategic program needs, and consolidate activities by functional area. The plan called for a 4-year process beginning in FY95 to realign the directorate`s facility portfolio through relocations, consolidations, transfer of facility ownership, demolition of trailers and new construction with a 20% sq/ft reduction as an end goal. As with all business driven initiatives, existing operating costs, implementation costs, cost avoidance and future operating costs were key metrics to measure against the strategic goal. Where P2 was not an essential element in the strategic planning process, it played a key role in the continuing success of the …
Date: August 29, 1997
Creator: Burgin, C. D. & Waterman, M. A.
System: The UNT Digital Library
Biomass Crop Production: Benefits for Soil Quality and Carbon Sequestration (open access)

Biomass Crop Production: Benefits for Soil Quality and Carbon Sequestration

Research at three locations in the southeastern US is quantifying changes in soil quality and soil carbon storage that occur during production of biomass crops compared with row crops. After three growing seasons, soil quality improved and soil carbon storage increased on plots planted to cottonwood, sycamore, sweetgum with a cover crop, switchgrass, and no-till corn. For tree crops, sequestered belowground carbon was found mainly in stumps and large roots. At the TN site, the coarse woody organic matter storage belowground was 1.3 Mg ha{sup {minus}1}yr{sup {minus}1}, of which 79% was stumps and large roots and 21% fine roots. Switchgrass at the AL site also stored considerable carbon belowground as coarse roots. Most of the carbon storage occurred mainly in the upper 30 cw although coarse roots were found to depths of greater than 60 cm. Biomass crops contributed to improvements in soil physical quality as well as increasing belowground carbon sequestration. The distribution and extent of carbon sequestration depends on the growth characteristics and age of the individual biomass crop species. Time and increasing crop maturity will determine the potential of these biomass crops to significantly contribute to the overall national goal of increasing carbon sequestration and reducing greenhouse …
Date: August 29, 1999
Creator: Bandaranayake, W.; Bock, B. R.; Houston, A.; Joslin, J. D.; Pettry, D. E.; Schoenholtz, S. et al.
System: The UNT Digital Library
Challenges using a {sup 252}Cf shuffler instrument in a plant environment to measure mixtures of uranium and plutonium transuranic waste (open access)

Challenges using a {sup 252}Cf shuffler instrument in a plant environment to measure mixtures of uranium and plutonium transuranic waste

An active-passive {sup 252}Cf shuffler instrument, installed and certified several years ago at Los Alamos National Laboratory's plutonium facility, has now been calibrated for different matrices to measure Waste Isolation Pilot Plant (WIPP)-destined transuranic (TRU) waste. Little or no data currently exist for these types of measurements in plant environments where sudden large changes in the neutron background radiation can significantly distort the results. Measurements and analyses of twenty-two 55-gallon drums, consisting of mixtures of varying quantities of uranium and plutonium in mostly noncombustible matrices, have been recently completed at the plutonium facility. The calibration and measurement techniques, including the method used to separate out the plutonium component, will be presented and discussed. Calculations used to adjust for differences in uranium enrichment from that of the calibration standards will be shown. Methods used to determine various sources of both random and systematic error will be indicated. Particular attention will be directed to those problems identified as arising from the plant environment. The results of studies to quantify the aforementioned distortion effects in the data will be presented. Various solution scenarios will be outlined, along with those adopted here.
Date: August 29, 1999
Creator: Hurd, J. R.
System: The UNT Digital Library
Electromagnetic Compatibility in Nuclear Power Plants (open access)

Electromagnetic Compatibility in Nuclear Power Plants

Electromagnetic compatibility (EMC) has long been a key element of qualification for mission critical instrumentation and control (I&C) systems used by the U.S. military. The potential for disruption of safety-related I&C systems by electromagnetic interference (EMI), radio-frequency interference (RFI), or power surges is also an issue of concern for the nuclear industry. Experimental investigations of the potential vulnerability of advanced safety systems to EMI/RFI, coupled with studies of reported events at nuclear power plants (NPPs) that are attributed to EMI/RFI, confirm the safety significance of EMC for both analog and digital technology. As a result, Oak Ridge National Laboratory has been engaged in the development of the technical basis for guidance that addresses EMC for safety-related I&C systems in NPPs. This research has involved the identification of engineering practices to minimize the potential impact of EMI/RFI and power surges and an evaluation of the ambient electromagnetic environment at NPPs to tailor those practices for use by the nuclear industry. Recommendations for EMC guidance have been derived from these research findings and are summarized in this paper.
Date: August 29, 1999
Creator: Ewing, P. D.; Kercel, S. W.; Korsah, K. & Wood, R. T.
System: The UNT Digital Library