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(open access)

1/12-scale physical modeling experiments in support of tank 241-SY- 101 hydrogen mitigation

Hanford tank 241-SY-101 is a 75-ft-dia double-shell tank that contains approximately 1.1 M gal of radioactive fuel reprocessing waste. Core samples have shown that the tank contents are separated into two main layers, a article laden supernatant liquid at the top of the tank and a more dense slurry on the bottom. Two additional layers may be present, one being a potentially thick sludge lying beneath the slurry at the bottom of the tank and the other being the crust that has formed on the surface of the supernatant liquid. The supernatant is more commonly referred to as the convective layer and the slurry as the non-convective layer. Accumulation of gas (partly hydrogen) in the non-convective layer is suspected to be the key mechanism behind the gas burp phenomena, and several mitigation schemes are being developed to encourage a more uniform gas release rate (Benegas 1992). To support the full-scale hydraulic mitigation test, scaled experiments were performed to satisfy two objectives: 1. provide an experimental database for numerical- model validation; 2. establish operating parameter values required to mobilize the settled solids and maintain the solids in suspension.

Date: January 1, 1993

Creator: Fort, J. A.; Bamberger, J. A.; Bates, J. M.; Enderlin, C. W. & Elmore, M. R.

Object Type: Report

System: The UNT Digital Library

(open access)

1/6TH SCALE STRIP EFFLUENT FEED TANK-MIXING RESULTS USING MCU SOLVENT

The purpose of this task was to determine if mixing was an issue for the entrainment and dispersion of the Modular Caustic Side Solvent Extraction (CSSX) Unit (MCU) solvent in the Defense Waste Processing Facility (DWPF) Strip Effluent Feed Tank (SEFT). The MCU strip effluent stream containing the Cs removed during salt processing will be transferred to the DWPF for immobilization in HLW glass. In lab-scale DWPF chemical process cell testing, mixing of the solvent in the dilute nitric acid solution proved problematic, and the Savannah River National Laboratory (SRNL) was requested to perform scaled SEFT mixing tests to evaluate whether the problem was symptomatic of the lab-scale set-up or of the solvent. The solvent levels tested were 228 and 235 ppm, which represented levels near the estimated DWPF solvent limit of 239 ppm in 0.001M HNO{sub 3} solution. The 239 ppm limit was calculated by Norato in X-CLC-S-00141. The general approach for the mixing investigation was to: (1) Investigate the use of fluorescent dyes to aid in observing the mixing behavior. Evaluate and compare the physical properties of the fluorescent dyed MCU solvents to the baseline Oak Ridge CSSX solvent. Based on the data, use the dyed MCU solvent …

Date: February 1, 2006

Creator: Hansen, E.

Object Type: Report

System: The UNT Digital Library

(open access)

1. 8K conditioning (non-quench training) of a model SSC dipole

The accepted hypothesis is that training quenches are caused by heat generation when conductors move under Lorentz force. Afterwards no conductor motion will occur until a higher field and greater Lorentz force acts. If superior heat transfer and/or greater temperature margin is provided by operating at lower bath temperature, one might expect that the heat generated by conductor motion will not cause a runaway temperature increase, or quench. To test this hypothesis, the central dipole field in SSC model magnets was ramped at 1.8 K to 7.1 tesla without the magnets' quenching. The bath was then raised to 4.4 K and the magnets quenched at their short sample limits of 6.6 tesla or higher. Comparison with similar magnets trained in He I at 4.4 K is made and the significance of the non-quench training on system operation is discussed.

Date: September 1, 1986

Creator: Gilbert, W. S. & Hassenzahl, W. V.

Object Type: Article

System: The UNT Digital Library

(open access)

E-1 Common Analog Model (U)

This report is the descriptive description of the E-1 common analog model

Date: July 1, 1969

Creator: unknown

Object Type: Report

System: The UNT Digital Library

(open access)

1-D closure models for slender 3-D viscoelastic free jets: von Karman flow geometry and elliptical cross section

In this paper we derive one space dimensional, reduced systems of equations (1-D closure models) for viscoelastic free jets. We begin with the three-dimensional system of conservation laws and a Maxwell-Jeffreys constitutive law for an incompressible viscoelastic fluid. First, we exhibit exact truncations to a finite, closed system of 1-D equations based on classical velocity assumptions of von Karman. Next, we demonstrate that the 3-D free surface boundary conditions overconstrain these truncated systems, so that only a very limited class of solutions exist. We then proceed to derive approximate 1-D closure theories through a slender jet asymptotic scaling, combined with appropriate definitions of velocity, pressure and stress unknowns. Our nonaxisymmetric 1-D slender jet models incorporate the physical effects of inertia, viscoelasticity (viscosity, relaxation and retardation), gravity, surface tension, and properties of the ambient fluid, and include shear stresses and time dependence. Previous special 1-D slender jet models correspond to the lowest order equations in the present asymptotic theory by an a posteriori suppression to leading order of some of these effects, and a reduction to axisymmetry. Solutions of the lowest order system of equations in this asymptotic analysis are presented: For the special cases of elliptical inviscid and Newtonian free …

Date: January 1, 1988

Creator: Bechtel, S. E.; Forest, M. G.; Holm, D. D. & Lin, K. J.

Object Type: Article

System: The UNT Digital Library

(open access)

1-D hybrid code for FRM start-up

A one-D hybrid has been developed to study the start-up of the FRM via neutral-beam injection. The code uses a multi-group numerical model originally developed by J. Willenberg to describe fusion product dynamics in a solenoidal plasma. Earlier we described such a model for use in determining self-consistent ion currents and magnetic fields in FRM start-up. However, consideration of electron dynamics during start-up indicate that the electron current will oppose the injected ion current and may even foil the attempt to achieve reversal. For this reason, we have combined the multi-group ion (model) with a fluid treatment for electron dynamics to form the hybrid code FROST (Field Reversed One-dimensional STart-up). The details of this merger, along with sample results of operation of FROST, are given.

Date: January 1, 1982

Creator: Stark, R. A. & Miley, G. H.

Object Type: Article

System: The UNT Digital Library

(open access)

A 1-D model for highly sensitive tubular reactors

We consider the steady state operation of wall-cooled, fixed-bed tubular reactors. In these reactors the temperature rise ..delta..T must normally be limited to small fractions of the adiabatic temperature rise ..delta..T/sub ad/, both to avoid runaway and maintain product selectivity. Yet ..delta..T/..delta..T/sub ad/ << 1 can only occur if eta = t/sub dif//t/sub reac/ << 1, where t/sub dif/ is the timescale on which heat escapes the reactor by ''diffusing'' to the cooled walls, and t/sub reac/ is the timescale over which the reaction occurs. So here we use asymptotic methods based on eta << 1 to analyze the 2-d reactor equations, and find the radial concentration and temperature profiles to leading order in eta. We then obtain a 1-d model of the reactor by substituting these asymptotically correct profiles into the reactor equations and averaging over r. This model, the ..cap alpha..-model, is identical to the standard (Beek and Singer) 1-d model, except that the reactor's overall heat transfer coefficient U is a decreasing function of the temperature rise ..delta..T. This occurs because as ..delta..T increases, the reaction becomes increasingly concentrated near r = 0, causing a decreased heat transfer efficiency through the reactor's walls. By comparing it with …

Date: January 1, 1987

Creator: Hagan, P. S.; Herskowitz, M. & Pirkle, J. C.

Object Type: Article

System: The UNT Digital Library

(open access)

1-Dimensional simulation of thermal annealing in a commercial nuclear power plant reactor pressure vessel wall section

The objective of this work was to provide experimental heat transfer boundary condition and reactor pressure vessel (RPV) section thermal response data that can be used to benchmark computer codes that simulate thermal annealing of RPVS. This specific protect was designed to provide the Electric Power Research Institute (EPRI) with experimental data that could be used to support the development of a thermal annealing model. A secondary benefit is to provide additional experimental data (e.g., thermal response of concrete reactor cavity wall) that could be of use in an annealing demonstration project. The setup comprised a heater assembly, a 1.2 in {times} 1.2 m {times} 17.1 cm thick [4 ft {times} 4 ft {times} 6.75 in] section of an RPV (A533B ferritic steel with stainless steel cladding), a mockup of the {open_quotes}mirror{close_quotes} insulation between the RPV and the concrete reactor cavity wall, and a 25.4 cm [10 in] thick concrete wall, 2.1 in {times} 2.1 in [10 ft {times} 10 ft] square. Experiments were performed at temperature heat-up/cooldown rates of 7, 14, and 28{degrees}C/hr [12.5, 25, and 50{degrees}F/hr] as measured on the heated face. A peak temperature of 454{degrees}C [850{degrees}F] was maintained on the heated face until the concrete wall …

Date: November 1, 1994

Creator: Nakos, J. T.; Rosinski, S. T. & Acton, R. U.

Object Type: Report

System: The UNT Digital Library

(open access)

1 - FFTF-LMFBR seal test program, July-September 1974

The objectives of the general seal test program are to: (1) conduct static and dynamic tests to demonstrate or determine the mechanical performance of full-size (cross-section) FFTF fuel transfer machine and reactor vessel head seals intended for use in a sodium vapor - inert gas environment, (2) demonstrate that these FFTF seals or new seal configurations provide acceptable fission product and cover gas retention capabilities at Clinch River Breeder Reactor Plant (CRBRP) operating environmental conditions other than radiation, (3) develop improved seals and seal technology for the CRBRP to support the national objective to reduce all atmospheric contaminations to low levels, and (4) publish a Design Guide for reactor seals along with Ordering Data. Test results for the quarter are presented.

Date: January 1, 1974

Creator: Kurzeka, W. & Oliva, R.

Object Type: Report

System: The UNT Digital Library

(open access)

1-GWh diurnal load-leveling Superconducting Magnetic Energy Storage system reference design

A point reference design has been completed for a 1-GWh Superconducting Magnetic Energy Storage system. The system is for electric utility diurnal load-leveling but can also function to meet much faster power demands including dynamic stabilization. This study explores several concepts of design not previously considered in the same detail as treated here. Because the study is for a point design, optimization in all respects is not complete. This report examines aspects of the coil, the superconductor supported off of the dewar shell, the dewar shell, and its configuration and stresses, the underground excavation and construction for holding the superconducting coil and its dewar, the helium refrigeration system, the electrical converter system, the vacuum system, the guard coil, and the costs. This report is divided into two major portions. The first is a general treatment of the work and the second is seven detailed technical appendices issued as separate reports. The information presented on the aluminum stabilizer for the conductor, on the excavation, and on the converter is based upon industrial studies contracted for this work.

Date: September 1, 1979

Creator: Rogers, J. D.; Hassenzahl, W. V. & Schermer, R. I. (comps.)

Object Type: Report

System: The UNT Digital Library

(open access)

1-GWh diurnal load-leveling superconducting magnetic energy storage system reference design. Appendix A: energy storage coil and superconductor

The technical aspects of a 1-GWh Superconducting Magnetic Energy Storage (SMES) coil for use as a diurnal load-leveling device in an electric utility system are presented. The superconductor for the coil is analyzed, and costs for the entire coil are developed.

Date: September 1, 1979

Creator: Schermer, R.I.

Object Type: Report

System: The UNT Digital Library

(open access)

1-GWh diurnal load-leveling superconducting magnetic energy storage system reference design. Appendix B: cost study, high-purity aluminum production

Cost information is supplied for aluminum with purities of 200, 2000, and 5000 residual resistivity ratio. Two production situations were used for each purity: (1) 1 x 10/sup 6/ kg/yr production rate with a 30-yr sustaining market and (2) 1 x 10/sup 6/ kg/yr production rate for 2 yrs only. These productions and purities are of interest for manufacturing devices for Superconducting Magnetic Energy Storage. The cost study results are presented as a range and include (1) the selling price of the aluminum for each case, (2) the cost of facilities including construction, engineering, and related costs, (3) the cost of money and depreciation (interest/amortization), and (4) the energy costs - the total of power and fuel. The range is affected by possible production variations and other uncertainties. Information is also given on plant location options and the preferred feed to the purification facility (with ore source effects).

Date: September 1, 1979

Creator: Cochran, C. N.; Dawless, R. K. & Whitchurch, J. B.

Object Type: Report

System: The UNT Digital Library

(open access)

1-GWh diurnal load-leveling superconducting magnetic energy storage system reference design. Appendix C: dewar and structural support

The mechanical aspects of the dewar to contain a 1-GWh superconducting coil in a 1.8 K helium bath and the means for supporting the coil and dewar against the rock of an underground excavation created for just that purpose are presented.

Date: September 1, 1979

Creator: Bennett, J. G. & Ju, F. D.

Object Type: Report

System: The UNT Digital Library

(open access)

1-GWh diurnal load-leveling superconducting magnetic energy storage system reference design. Appendix D: superconductive magnetic energy storage cavern construction methods and costs

The excavation and preparation of an underground cavern to contain a 1-GWh diurnal load-leveling Superconducting Magnetic Energy Storage (SMES) unit is examined. The cavern's principal function is to provide a rock structure for supporting the magnetic forces from the charged storage coil. Certain economic considerations indicate the refrigerator cold box for the helium system should also be underground. The study includes such a provision and considers, among other things, rock bolting, water seepage, concrete lining of the walls, steel bearing pads, a system to prevent freezing of the walls, a mining schedule, and costs.

Date: September 1, 1979

Creator: unknown

Object Type: Report

System: The UNT Digital Library

(open access)

1-GWh diurnal load-leveling superconducting magnetic energy storage system reference design. Appendix F. 1-GWh electrical system design

Two circuit configurations for reducing the installed converter power and cost of high-power converter systems that operate in a constant-power mode over a wide current and voltage range are suggested and analyzed.

Date: September 1, 1979

Creator: Boenig, H. J.

Object Type: Report

System: The UNT Digital Library

(open access)

1/mc Terms in lambda+c Semileptonic Decays

We use the heavy quark effective theory to investigate the form factors that describe the semileptonic decays lambda+c -> lambda e+ nu, to order 1/mc. We find that a total of four form factors are needed to this order, in contrast with two form factors to leading order, and six form factors in the most general case. We point out some relationships that arise among the general form factors.

Date: February 1, 1992

Creator: Roberts, Winston

Object Type: Article

System: The UNT Digital Library

(open access)

1: Mass asymmetric fission barriers for {sup 98}Mo; 2: Synthesis and characterization of actinide-specific chelating agents

Excitation functions have been measured for complex fragment emission from the compound nucleus {sup 98}Mo, produced by the reaction of {sup 86}Kr with {sup 12}C. Mass asymmetric fission barriers have been obtained by fitting the excitation functions with a transition state formalism. The extracted barriers are {approximately} 5.7 MeV higher, on average, than the calculations of the Rotating Finite Range Model (RFRM). These data clearly show an isospin dependence of the conditional barriers when compared with the extracted barriers from {sup 90}Mo and {sup 94}Mo. Eleven different liquid/liquid extractants were synthesized based upon the chelating moieties 3,2-HOPO and 3,4-HOPO; additionally, two liquid/liquid extractants based upon the 1,2-HOPO chelating moiety were obtained for extraction studies. The Pu(IV) extractions, quite surprisingly, yielded results that were very different from the Fe(III) extractions. The first trend remained the same: the 1,2-HOPOs were the best extractants, followed closely by the 3,2-HOPOs, followed by the 3,4-HOPOs; but in these Pu(IV) extractions the 3,4-HOPOs performed much better than in the Fe(III) extractions. 129 refs.

Date: August 1, 1996

Creator: Veeck, A. C.

Object Type: Report

System: The UNT Digital Library

(open access)

A 1 MEGAWATT POLYPHASE BOOST CONVERTER-MODULATOR FOR KLYSTRON PULSE APPLICATION

This paper describes electrical design criteria and first operational results a 140 kV, 1 MW average, 11 MW peak, zero-voltage-switching 20 kHz polyphase bridge, boost converter/modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2300 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three ''H-Bridge'' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. PWM (pulse width modulation) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt-peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. A review of these design parameters and the first results of the performance characteristics will be presented.

Date: June 1, 2001

Creator: Reass, W. A.; Doss, J. D. & Gribble, R. F.

Object Type: Article

System: The UNT Digital Library

(open access)

1-MeV-Electron Irradiation of GaInAsN Cells: Preprint

This conference paper describes the GaInAsN cells that are measured to retain 933% and 894% of their original efficiency after exposure to 5 X 1014 and 1 X 1015 cm-2 1-MeV electrons, respectively. The rate of degradation is not correlated with the performance at beginning of life (BOL). The depletion width remains essentially unchanged, increasing by< 1%. Temperature-coefficient data for GaInAsN cells are also presented. These numbers are used to project the efficiency of GaInAsN-containing multijunction cells. The GaInAsN junction is not currently predicted to increase the efficiencies of the multijunction cells. Nevertheless, GaInAsN-containing multijunction cell efficiencies are predicted to be comparable to those of the conventional structures, and even small improvements in the GaInAsN cell may lead to higher multijunction cell efficiencies, especially for high-radiation applications and when cell operating temperature is low.

Date: May 1, 2002

Creator: Kurtz, Sarah; King, R. R.; Edmondson, K. M.; Friedman, D. J. & Karam, N. H.

Object Type: Article

System: The UNT Digital Library

(open access)

1 mil gold bond wire study.

In microcircuit fabrication, the diameter and length of a bond wire have been shown to both affect the current versus fusing time ratio of a bond wire as well as the gap length of the fused wire. This study investigated the impact of current level on the time-to-open and gap length of 1 mil by 60 mil gold bond wires. During the experiments, constant current was provided for a control set of bond wires for 250ms, 410ms and until the wire fused; non-destructively pull-tested wires for 250ms; and notched wires. The key findings were that as the current increases, the gap length increases and 73% of the bond wires will fuse at 1.8A, and 100% of the wires fuse at 1.9A within 60ms. Due to the limited scope of experiments and limited data analyzed, further investigation is encouraged to confirm these observations.

Date: May 1, 2013

Creator: Huff, Johnathon; McLean, Michael B.; Jenkins, Mark W. & Rutherford, Brian Milne

Object Type: Report

System: The UNT Digital Library

(open access)

1. Mono((8)annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

A reproducible, high-yield synthesis of mono((8)annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono((8)annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.

Date: October 1, 1991

Creator: Boussie, T. R.

Object Type: Report

System: The UNT Digital Library

(open access)

1. Mono([8]annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

A reproducible, high-yield synthesis of mono([8]annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono([8]annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.

Date: October 1, 1991

Creator: Boussie, T. R.

Object Type: Thesis or Dissertation

System: The UNT Digital Library

(open access)

1/N

There exist families of field theories with symmetry group SO(N) (or SU(N)) that become simpler as N becomes larger. More precisely, the solutions to these theories possess an expansion in powers of 1/N. This expansion is the subject of these lectures. The 1/N expansion can be used to analyze model field theories. The 1/N expansion is developed for phi/sup 4/ theory and applied to two two-dimensional models with similar combinatoric structures, the Gross-Neveu model and the CP/sup N-1/ model. These models display (in the leading 1/N approximation) such interesting phenomena as asymptotic freedom, dynamical symmetry breaking, dimensional transmutation, and non-perturbative confinement. It is possible that the 1/N expansion, with N the number of colors, might fruitfully be applied to quantum chromodynamics. Unfortunately, it is not possible to make a decisive test of the approximation, because no one knows how to compute even the first term in the expansion in closed form. However, it is possible to argue that this first term, whatever its detailed form, has many properties that are also shared by the real world, and which are otherwise underived from field theory. These include the saturation of scattering amplitudes by an infinite number of narrow resonances, the essential …

Date: March 1, 1980

Creator: Coleman, S.

Object Type: Report

System: The UNT Digital Library

(open access)

1 nA beam position monitoring system

A system has been developed at Jefferson Lab for measuring transverse position of very low current beams delivered to the Experimental Hall B of the Continuous Electron Beam Accelerator Facility (CEBAF). At the heart of the system is a position sensitive cavity operating at 1497 MHz. The cavity utilizes a unique design which achieves a high sensitivity to beam position at a relatively low cavity Q. The cavity output RF signal is processed using a down-converter and a commercial lock-in amplifier operating at 100 kHz. The system interfaces with a VME based EPICS control system using the IEEE, 488 bus. The main features of the system are simple and robust design, and wide dynamic range capable of handling beam currents from 1 nA to 1000 nA with an expected resolution better than 100 {mu}m. This paper outlines the design of the system.

Date: June 1, 1997

Creator: Ursic, R.; Flood, R. & Piller, C.

Object Type: Article

System: The UNT Digital Library

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