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Methodology for Comparing the Health Effects of Electricity Generation From Uranium and Coal Fuels (open access)

Methodology for Comparing the Health Effects of Electricity Generation From Uranium and Coal Fuels

A methodology was developed for comparing the health risks of electricity generation from uranium and coal fuels. The health effects attributable to the construction, operation, and decommissioning of each facility in the two fuel cycle were considered. The methodology is based on defining (1) requirement variables for the materials, energy, etc., (2) effluent variables associated with the requirement variables as well as with the fuel cycle facility operation, and (3) health impact variables for effluents and accidents. The materials, energy, etc., required for construction, operation, and decommissioning of each fuel cycle facility are defined as primary variables. The materials, energy, etc., needed to produce the primary variable are defined as secondary requirement variables. Each requirement variable (primary, secondary, etc.) has associated effluent variables and health impact variables. A diverging chain or tree is formed for each primary variable. Fortunately, most elements reoccur frequently to reduce the level of analysis complexity. 6 references, 11 figures, 6 tables.
Date: December 8, 1981
Creator: Rhyne, W. R. & El-Bassioni, A. A.
System: The UNT Digital Library
Low-level-signal data acquisition for the MFTF superconducting-magnet system (open access)

Low-level-signal data acquisition for the MFTF superconducting-magnet system

Acquisition of low level signals from sensors mounted on the superconducting yin-yang magnet in the Mirror Fusion Test Facility (MFTF) imposes very strict requirements on the magnet signal conditioning and data acquisition system. Of the various types of sensors required, thermocouples, strain gages, and voltage taps produce very low level outputs. These low level outputs must be accurately measured in the harsh environment of slowly varying magnetic fields, cryogenic temperatures, high vacuum, pulse power and 60 Hz electrical noise, possible neutron radiation, and high common mode voltage resulting from superconducting magnet quench. Successful measurements require careful attention to grounding, shielding, signal handling and processing in the data acquisition system. The magnet instrumentation system provides a means of effectively measuring both low level signals and high level signals from all types of sensors.
Date: October 8, 1981
Creator: Montoya, C.R.
System: The UNT Digital Library
Automatic gas-levitation system for vacuum deposition of laser-fusion targets (open access)

Automatic gas-levitation system for vacuum deposition of laser-fusion targets

An improved simple system has been developed to gas-levitate microspheres during vacuum-deposition processes. The automatic operation relies on two effects: a lateral stabilizing force provided by a centering-ring; and an automatically incremented gas metering system to offset weight increases during coating.
Date: September 8, 1981
Creator: Jordan, C. W.; Cameron, G. R.; Krenik, R. M. & Crane, J. K.
System: The UNT Digital Library
Copper-coated laser-fusion targets using molecular-beam levitation (open access)

Copper-coated laser-fusion targets using molecular-beam levitation

A series of diagnostic experiments at the Shiva laser fusion facility required targets of glass microspheres coated with 1.5 to 3.0 ..mu..m of copper. Previous batch coating efforts using vibration techniques gave poor results due to microsphere sticking and vacuum welding. Molecular Beam Levitation (MBL) represented a noncontact method to produce a sputtered copper coating on a single glassmicrosphere. The coating specifications that were achieved resulted in a copper layer up to 3 ..mu..m thick with the allowance of a maximum variation of 10 nm in surface finish and thickness. These techniques developed with the MBL may be applied to sputter coat many soft metals for fusion target applications.
Date: September 8, 1981
Creator: Rocke, M. J.
System: The UNT Digital Library
Incorporation of chemical kinetic models into process control (open access)

Incorporation of chemical kinetic models into process control

An important consideration in chemical process control is to determine the precise rationing of reactant streams, particularly when a large time delay exists between the mixing of the reactants and the measurement of the product. In this paper, a method is described for incorporating chemical kinetic models into the control strategy in order to achieve optimum operating conditions. The system is first characterized by determining a reaction rate surface as a function of all input reactant concentrations over a feasible range. A nonlinear constrained optimization program is then used to determine the combination of reactants which produces the specified yield at minimum cost. This operating condition is then used to establish the nominal concentrations of the reactants. The actual operation is determined through a feedback control system employing a Smith predictor. The method is demonstrated on a laboratory bench scale enzyme reactor.
Date: July 8, 1981
Creator: Herget, C.J. & Frazer, J.W.
System: The UNT Digital Library
Some proposed disk-heating and beam-transport experiments for heavy-ion inertial-fusion test facilities (open access)

Some proposed disk-heating and beam-transport experiments for heavy-ion inertial-fusion test facilities

Calculations suggest that experiments relating to beam deposition, focusing and transport can be performed within the context of current design proposals for accelerator test-facilities. Since the test-facilities have lower ion kinetic energy and beam pulse power as compared to reactor drivers, we achieve high-beam intensities at the focal spot by using short focal distance and properly designed beam optics. In this regard, the low beam emittance of suggested multi-beam designs are very useful. Preliminary results suggest that intensities close to 10/sup 14/ W/cm/sup 2/ are achievable. Given these intensities, deposition experiments with heating of disks to greater than a million degrees Kelvin (100 eV) are expected. We could also expect as much as 1 to 3 kA of incident ion current on these disks with beam intensities almost comparable to that of reactor targets.
Date: June 8, 1981
Creator: Mark, J. W. K.; Bangerter, R. O.; Fawley, W. M.; Yu, S. & Wang, T. S. F.
System: The UNT Digital Library
Electromagnetic velocity gauge: use of multiple gauges, time response, and flow perturbations (open access)

Electromagnetic velocity gauge: use of multiple gauges, time response, and flow perturbations

We have developed an in-situ electromagnetic velocity (EMV) gauge system for use in multiple-gauge studies of initiating and detonating explosives. We have also investigated the risetime of the gauge and the manner in which it perturbs a reactive flow. We report on the special precautions that are necessary in multiple gauge experiments to reduce lead spreading, simplify target fabrication problems and minimize cross talk through the conducting explosive. Agreement between measured stress records and calculations from multiple velocity gauge data give us confidence that our velocity gauges are recording properly. We have used laser velocity interferometry to measure the gauge risetime in polymethyl methacrylate (PMMA). To resolve the difference in the two methods, we have examined hydrodynamic and material rate effects. In addition, we considered the effects of shock tilt, electronic response and magntic diffusion on the gauge's response time.
Date: April 8, 1981
Creator: Erickson, L. M.; Johnson, C. B.; Parker, N. L.; Vantine, H. C.; Weingart, R. C. & Lee, R. S.
System: The UNT Digital Library