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Containment and recovery system for fuel-reprocessing plants
Tritium containment and removal problems in a fuel-reprocessing plant are identified and conceptual process designs for reducing emissions to the environment to below 1 Ci/day are studied. The conceptual design recommended would allow an air atmosphere in the reprocessing-plant hall and would use a continuous-catalytic-oxidizer/molecular-sieve-adsorber cleanup system to maintain a 40-..mu..Ci/m/sup 3/ tritium level (5 ..mu..Ci/m/sup 3/ HTO) against 180 Ci/day leakage from components and process piping.
Date:
August 25, 1976
Creator:
Galloway, T. R.
Object Type:
Article
System:
The UNT Digital Library
Raman spectroscopic studies of isotopic diatomic molecules and a technique for measuring stable isotope ratios using Raman scattering. [Cross sections]
A method for measuring stable isotope ratios using Raman scattering has been developed. This method consists of simultaneously counting photons scattered out of a high-intensity laser beam by different isotopically-substituted molecules. A number of studies of isotopic diatomic molecules have been made. The Q-branches of the Raman spectra of the isotopic molecules /sup 14/N/sup 15/N and /sup 16/O/sup 18/O were observed at natural abundance in nitrogen and oxygen samples. Comparison of the ratios of the intensities of the Q-branches of the major nitrogen and oxygen isotopic molecules with mass spectrometric determinations of the isotopic compositions yielded scattering cross sections of /sup 14/N/sup 15/N relative to /sup 14/N/sup 14/N and /sup 16/O/sup 18/O relative to /sup 16/O/sup 16/O. These cross section ratios differ from unity, a difference which can be explained by considering nuclear mass effects on the Franck-Condon factors of the molecular transitions. The measured intensities of the /sup 14/N/sup 15/N and /sup 16/O/sup 18/O Q-branches provided the baseline data needed to make the previously-mentioned extrapolation. High-resolution (approximately 0.15 cm/sup -1/) spectra of the Q-branches of /sup 14/N/sup 14/N and /sup 16/O/sup 16/O yielded a direct determination of ..cap alpha../sub e/ (the difference between the rotational constant in the ground …
Date:
May 25, 1976
Creator:
Harney, R. C.
Object Type:
Report
System:
The UNT Digital Library
Pass or fail: A new test for password legitimacy
While other programs check for bad passwords after the fact, it in important to have good passwords at all times, not just after the latest Crack run. To this end we have modified Larry Wall's Perl password program and added, among other features, the ability to check a sorted list of all the bad passwords'' that Crack will generate, given all the dictionaries that we could get our hands on (107 MB of unique words, so far). The combination of improvements has turned publicly available code into a powerful tool that can aid sites in the maintenance of local security.
Date:
September 25, 1992
Creator:
Cherry, Andrew; Henderson, Mark W.; Nickless, William K.; Olson, Robert & Rackow, Gene
Object Type:
Article
System:
The UNT Digital Library
Slicing of silicon into sheet material. Silicon sheet growth development for the large area silicon sheet task of the low cost silicon solar array project. Second quarterly report, March 22, 1976--June 20, 1976
Slicing tests of silicon to show the dependence of cutting rate on operating conditions are complete. Cutting rate is linear with cutting force per blade and bladehead speed, and inversely proportional to kerf width (loss) and kerf length. The dimensionless parameter of cutting efficiency is a good measure of the performance of a multiblade slicing system. Low contact pressure between the blades and the silicon workpiece result in increased wafer accuracy and cutting efficiency. Blade wear seems to be stable for all slicing tests, and is slightly lower with low cutting pressure. (WDM)
Date:
June 25, 1976
Creator:
Holden, S. C.
Object Type:
Report
System:
The UNT Digital Library
Mechanical design aspects of a tandem mirror fusion reactor
Two ''plugs'' of dense plasma at either end of a central solenoid cell form the basis of a new mirror fusion power plant concept. A central cell blanket design is presented. Modules on crawler tracks serviced by remote welding and handling machines of very simple design are important features resulting from linear axisymmetric geometry. Three blanket designs are considered and the best one presented in some detail. It has lithium as the breeder material, helium cooled. ''Plug'' magnet field strengths must be high. A novel magnet is presented to satisfy the physics of the end plugs. Beam sources at 1,200 KV present special problems. Methods of voltage standoff, arc damage control, and neutralization are discussed. New secondary containment ideas are presented to allow removable roof sections of balanced design.
Date:
April 25, 1977
Creator:
Neef, W. S. Jr.
Object Type:
Article
System:
The UNT Digital Library
Free-flow variability on the Jess and Souza Ranches, Altamont Pass
A central monitoring computer was installed on each ranch. The computers were connected by communication cables to 50 turbines on the Souza Ranch and 150 turbines on the Jess Ranch. Anemometers were installed on every other turbine on 12-foot booms at 35 feet above ground level (AGL). Spacing between anemometers was approximately 200 feet in the crosswind direction by 500 feet in the parallel direction. A total of 23 turbines on the Souza Ranch was instrumented in this fashion, as well as two multi-level meteorological towers. On the Jess Ranch, 77 turbines were instrumented; about half at 35 feet AGL and half at 50 feet AGL, plus four additional towers. Wind data were collected for approximately a 100 hour period on each ranch. All turbines were shut down during these periods so that no turbine wakes would be present. The data periods were selected by the meteorologist to insure that they occurred during typical spring-summer flow regimes. The terrain features upwind of the site appear to play as significant a role in the flow variability as terrain features within the site.
Date:
April 25, 1988
Creator:
Nierenberg, R.
Object Type:
Report
System:
The UNT Digital Library
Large-scale cryopumping for controlled fusion
Vacuum pumping by freezing out or otherwise immobilizing the pumped gas is an old concept. In several plasma physics experiments for controlled fusion research, cryopumping has been used to provide clean, ultrahigh vacua. Present day fusion research devices, which rely almost universally upon neutral beams for heating, are high gas throughput systems, the pumping of which is best accomplished by cryopumping in the high mass-flow, moderate-to-high vacuum regime. Cryopumping systems have been developed for neutral beam injection systems on several fusion experiments (HVTS, TFTR) and are being developed for the overall pumping of a large, high-throughput mirror containment experiment (MFTF). In operation, these large cryopumps will require periodic defrosting, some schemes for which are discussed, along with other operational considerations. The development of cryopumps for fusion reactors is begun with the TFTR and MFTF systems. Likely paths for necessary further development for power-producing reactors are also discussed.
Date:
July 25, 1977
Creator:
Pittenger, L. C.
Object Type:
Article
System:
The UNT Digital Library
Final report on geological studies pertinent to site suitability criteria for high-level waste repositories
This document contains information on (1) the hydraulic conductivity of salt; (2) the various types of naturally occurring salt solution collapse features, and (3) the rate of formation of solution cavities in salt. (LK)
Date:
May 25, 1977
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Analysis of the custom design/fabrication/testing requirements for a large-hole drilling machine for use in an underground radioactive waste repository
An analysis of the fabrication and field test requirements for a drilling machine that would be applicable to the drilling of large diameter holes for the emplacement of radioactive waste canisters in an underground repository is presented. On the basis of a previous study in 1975 by RE/SPEC Inc. for the Oak Ridge National Laboratory, it was concluded that none of the commercially available machines were ideally suited for the desired drilling application, and that it was doubtful whether a machine with the required capabilities would become available as a standard equipment item. The results of the current study, as presented here, provide a definitive basis for selecting the desired specifications, estimating the design, fabrication, and testing costs, and analyzing the cost-benefit characteristics of a custom-designed drilling machine for the emplacement hole drilling task.
Date:
October 25, 1976
Creator:
Grams, W. H. & Gnirk, P. F.
Object Type:
Report
System:
The UNT Digital Library
Synthesis of Accretion Disk and Nonthermal Source Models for AGN
A scenario for the central engine of AGN has been developed consisting of a massive black hole (MBH) onto which gas accretes through an accretion disk. The accretion disk radiates the observed optical and ultraviolet continua. Surrounding the MBH is a nonthermal source which produces the infrared and soft x-ray continua by synchrotron emission, and the x-ray spectrum by inverse Compton scattering of the optical-ultraviolet photons from the accretion disk. Previously we modeled the accretion disk (M.A.M.) and nonthermal source (D.L.B.) separately, and here we combine the two models to form a unified description of the AGN engine. This combined model can be inverted to determine source parameters from observed spectra. A group of AGN for which multiband observations exist can then be modeled to: demonstrate the validity of the combined model for a large number of objects; establish the range of parameter values that describe the source; and search for any correlations between source description and type.
Date:
May 25, 1988
Creator:
Band, D. L. & Malkan, M. A.
Object Type:
Article
System:
The UNT Digital Library
Geophysical and geochemical models of the Earth's shields and rift zones
This report summarizes a collection of, synthesis of, and speculation on the geophysical and geochemical models of the earth's stable shields and rift zones. Two basic crustal types, continental and oceanic, and two basic mantle types, stable and unstable, are described. It is pointed out that both the crust and upper mantle play a strongly interactive role with surface geological phenomena ranging from the occurrence of mountains, ocean trenches, oceanic and continental rifts to geographic distributions of earthquakes, faults, and volcanoes. On the composition of the mantle, there is little doubt regarding the view that olivine constitutes a major fraction of the mineralogy of the earth's upper mantle. Studies are suggested to simulate the elasticity and composition of the earth's lower crust and upper mantle.
Date:
February 25, 1977
Creator:
Chung, D. H.
Object Type:
Report
System:
The UNT Digital Library
Tritium control in a mirror-fusion central power station
Tritium-containment systems for the blanket and power systems of a mirror-fusion reactor are described. These systems are designed to reduce emissions to below 1 Ci/d. The overall conceptual design uses air as the reactor-hall atmosphere. A continuous catalytic oxidizer-molecular sieve adsorber cleanup system would be used to control a 180-Ci/d leakage from reactor components, energy recovery systems, and process piping. Such a system would maintain a 40 ..mu..Ci/m/sup 3/ tritium level (5 ..mu..Ci/m/sup 3/ HTO) in the hall. The blanket considered contains submodules with Li/sub 2/Be/sub 2/O/sub 3/-Be for tritium breeding. This canned breeding material is scavenged with a lithium-vapor-doped helium gas stream. The container consists of molybdenum alloy (TZM) tubes and tube sheets with the breeding material packed and sintered in the shell surrounding the tubes. Potassium vapor coolant (also lithium-doped) passes through these tubes to recover the heat at 950/sup 0/C. Leakage following an intermediate TZM exchanger would result in a loss of 0.7 Ci/d into the steam through the Haynes-25 alloy boiler (potassium boiling). A moving getter bed is used to recover the tritium from the LiT and Li/sub 2/T scavengers in both the helium blanket scavenging flow and the potassium vapor coolant.
Date:
August 25, 1976
Creator:
Galloway, T. R.
Object Type:
Article
System:
The UNT Digital Library
Tank study committee report
Six major problem areas have surfaced in the past twenty-five years concerning the use of plutonium tankage. The most significant of these involves the use of borosilicate glass as a neutron absorber. Approximately thirty recommendations and criteria resulted from a study of these problem areas. Not all of the criteria and recommendations are unanimously supported by all members of the committee. The committee agrees that problem areas that can be handled on a short-term basis are being pursued expeditiously. Most of the criteria presented will apply to new tankage to be installed. The committee also noted fourteen accomplishments in the last 1/sup 1///sub 2/ years directed to the application of the criteria.
Date:
February 25, 1977
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Development of optimum conditions for drying ion exchange resin in a fluidized bed dryer
Drying of Amberlite IRC-72 ion exchange resin in a fluidized bed dryer was investigated. Resin water content was measured as a function of drying time for various drying temperatures, bed loadings, and air flow rates. An incomplete equation for the induction period and complete model for constant rate drying were developed. Further development of an induction period model requires installation of an accurate air flow measurement device. A drying temperature of 200/sup 0/F results in the shortest drying time with no resin damage. Optimization of the process with regard to other process parameters requires development of a complete drying model. (auth)
Date:
February 25, 1976
Creator:
Vora, J. N.; Michaels, S. L. & Stiros, P.
Object Type:
Report
System:
The UNT Digital Library
Role of space charge in beam transport. [Review]
Space charge as it affects ion beam transport is reviewed. The approach here will be to derive beam-current criteria for divergence from space charge, review recent theoretical models for fractional space-charge neutralization, discuss space-charge-related observations on ion-beam transport in a specific experimental system, and briefly note several applications using space charge. Experimental measurements of effective space charge are discussed for a dc ion-source test stand using a 90/sup 0/ double-focusing magnet for species separation and for a solenoidal lens magnet for trim focus of the ion beam preparatory to entrance into a 400-kV accelerator column.
Date:
March 25, 1977
Creator:
Osher, J. E.
Object Type:
Article
System:
The UNT Digital Library
DT fusion neutron irradiation of ANL electron microscopy samples, LLL ''tritium-tricked'' niobium, LLL Al/sub 2/O/sub 3/, SiC, and B/sub 4/C, and an LLL sputtering experiment
The experimental procedure for irradiating the above specimens is given. No results are presented. (MOW)
Date:
February 25, 1976
Creator:
MacLean, S. C.
Object Type:
Report
System:
The UNT Digital Library
Solid state chemistry of rare earth oxides. Technical progress report, 1974--1975. [High-resolution electron optical methods at 3 A resolution]
Electron microscope images obtained at about 3A resolution for Pr/sub 7/O/sub 12/ (and isomorphous Zr/sub 3/Sc/sub 4/O/sub 12/) are in excellent agreement with calculated images based upon the structure determined separately by total profile neutron powder diffraction analysis. The image calculation programs establish the efficacy of lattice image interpretation in structural terms for these types of related phases whose structures are as yet beyond conventional means to determine. Such images for several other intermediate phases are interpreted and structures proposed. Finally, images of crystals which can be made to undergo reaction within the microscope are interpreted according to the structures involved. These studies reveal the role of intergrowth and topotaxy in these systems. (auth)
Date:
June 25, 1975
Creator:
Eyring, LeRoy; Summerville, Edward & Skarnulis, A. Jerome
Object Type:
Report
System:
The UNT Digital Library
Studies of combustion reactions at the state-resolved differential cross section level
State-resolved differential reaction cross sections provide perhaps the most detailed information about the mechanism of chemical reaction, but heretofore they have been extremely difficult to measure. This program explores a new technique for obtaining differential cross sections with product state resolution. The three-dimensional velocity distribution of state-selected reaction products is determined by ionizing the appropriate product, waiting for a delay while it recoils along the trajectory imparted by the reaction, and finally projecting the spatial distribution of ions onto a two dimensional screen using a pulsed electric field. Knowledge of the arrival time allows the ion position to be converted to a velocity, and the density of velocity projections can be inverted mathematically to provide the three-dimensional velocity distribution for the selected product. The main apparatus has been constructed and tested using photodissociations. The proposed research will both develop the new technique and employ it to investigate methyl radical, formyl radical, and hydrogen atom reactions which are important in combustion processes. We intend specifically to characterize the reactions of CH{sub 3} with H{sub 2} and H{sub 2}CO; of HCO with O{sub 2}; and of H with CH{sub 4},CO{sub 2}, and O{sub 2}.
Date:
March 25, 1992
Creator:
Houston, P. L.
Object Type:
Report
System:
The UNT Digital Library
Blistering effects in neutral injection systems operated with helium and hydrogen gases: a preliminary assessment
The practical effects of blistering and flaking in neutral injection systems are studied. These effects will soon be more important because of energy increases in systems now under development and because of their operation with fast helium ions as well as hydrogen and deuterium ions. Two main effects were studied: enhanced erosion rate and possible voltage breakdown from sharp flakes and gas emission.
Date:
January 25, 1977
Creator:
Hamilton, G. W.
Object Type:
Report
System:
The UNT Digital Library
KEWB facilities decontamination and disposition. Final report
The decontamination and disposition of the KEWB facilities, Buildings 073, 643, 123, and 793, are complete. All of the facility equipment, including reactor enclosure, reactor vessel, fuel handling systems, controls, radioactive waste systems, exhaust systems, electrical services, and protective systems were removed from the site. Buildings 643, 123, and 793 were completely removed, including foundations. The floor and portions of the walls of Building 073 were covered over by final grading. Results of the radiological monitoring and the final survey are presented. 9 tables, 19 figures. (auth)
Date:
February 25, 1976
Creator:
Ureda, B. F.
Object Type:
Report
System:
The UNT Digital Library
Biological processes in the water column of the South Atlantic Bight: Zooplankton responses
This study sought to determine and understand the major processes governing the abundance, distribution, composition and eventual fate of zooplankton on the southeastern shelf of the US in relation to water circulation. Over much of the shelf circulation is dominated by the Gulf Stream and/or atmospheric forcing. Most of our studies concentrated on processes on the middle and outer shelf. On the latter, pronounced biological production occurs year-round at frequent intervals and is due to Gulf Stream eddies which move by at an average frequency of one every week. These eddies are rich in nutrients which, when upwelled into the euphoric zone, lead to pronounced primary production which then triggers zooplankton production.
Date:
September 25, 1992
Creator:
Paffenhofer, G. A.
Object Type:
Report
System:
The UNT Digital Library
Evaluation of existing polymer characterization techniques and capabilities of the General Chemistry and Organic Materials Divisions in the Chemistry and Materials Science Department
This report begins with definitions of characterization and testing, then continues with the evaluation of thirteen specific techniques including various spectroscopy, thermal, solutional properties, wet chemistry, chromatography and miscellaneous procedures. Comments and recommendations on the need for an analytical services focal point in GCD, a polymer characterization expert in OMD and the use of contractor facilities as a source of data gathering are made. It is concluded that substantial capabilities for polymer characterization do exist at LLL, but lack of adequate interfacing between OMD and GCD is preventing their effective use. Acquisition of a polymer chemist with experience in characterization techniques appears to be the best solution to this problem. Two tables outlining schemes for a check list for polymer characterization techniques and list of techniques and information needed for aging effects studies are included for reference. (DLC)
Date:
August 25, 1976
Creator:
Larsen, Fred N.
Object Type:
Report
System:
The UNT Digital Library
Building 003 decontamination and disposition. Final report
The decontamination and disposition (D and D) of the contaminated facilities in Building 003 are complete. The Hot Cave, the building radioactive exhaust system, the radioactive liquid waste system, and the fume hoods were removed. The more significant D and D activities are summarized, special techniques are noted, and problems and their resolution are discussed. Results of the radiological monitoring are presented. (auth)
Date:
February 25, 1976
Creator:
Ureda, B. F.
Object Type:
Report
System:
The UNT Digital Library
Geochemistry of Delaware Basin groundwaters
Fluids from various formations were sampled and analyzed in order to characterize groundwaters in the Delaware Basin. Waters were analyzed for solute content and/or stable isotope ratios (D/H and /sup 18/O//sup 16/O). Three lines of geochemical arguments are summarized, in order to present the natures and probable origins of analyzed fluids: solute chemistry, thermodynamic modelling of low-temperature aqueous species, and stable isotope ratios. (JGB)
Date:
April 25, 1977
Creator:
Lambert, S. J.
Object Type:
Article
System:
The UNT Digital Library