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SWSA (Solid Waste Storage Area) 6 tumulus disposal demonstration (open access)

SWSA (Solid Waste Storage Area) 6 tumulus disposal demonstration

A facility to demonstrate the above-grade disposal of solid low-level radioactive wastes (LLW) is being constructed in the Solid Waste Storage Area 6 (SWSA 6) at the Oak Ridge National Laboratory (ORNL). The demonstration facility will utilize the ''Tumulus'' technology, which basically involves sealing the waste in concrete vaults, placing the vaults on a grade level concrete pad, and covering the pad with a soil cover after vault placement is complete. Loading of the demonstration unit is scheduled to begin in June, and will continue one to one and a half years until the 28,000 ft/sup 3/ capacity is exhausted.
Date: January 1, 1987
Creator: Van Hoesen, S. D. & Clapp, R. B.
System: The UNT Digital Library
Evaluation of potential mixed wastes containing lead, chromium, or used oil (open access)

Evaluation of potential mixed wastes containing lead, chromium, or used oil

This paper presents the results of follow-on studies conducted by Brookhaven National Laboratory (BNL) for the Nuclear Regulatory Commission (NRC) on certain kinds of low-level waste (LLW) which could also be classified as hazardous waste subject to regulation by the Environmental Protection Agency (EPA). Such LLW is termed ''mixed waste.'' Additional data have been collected and evaluated on two categories of potential mixed waste, namely LLW containing metallic lead and LLW containing chromium. Additionally, LLW with organic liquids, especially liquid scintillation wastes, are reviewed. In light of a proposed EPA rule to list used oil as hazardous waste, the potential mixed waste hazard of used oil contaminated with radionuclides is discussed. It is concluded that the EPA test for determining whether a solid waste exhibits the hazardous characteristic of extraction procedure toxicity does not adequately simulate the burial environment at LLW disposal sites, and in particular, does not adequately assess the potential for dissolution and transport of buried metallic lead. Also, although chromates are, in general, not a normal or routine constitutent in commercial LLW (with the possible exception of chemical decontamination wastes), light water reactors which do use chromates might find it beneficial to consider alternative corrosion inhibitors. In …
Date: January 1, 1987
Creator: Siskind, B.; MacKenzie, D. R.; Bowerman, B. S.; Kempf, C. R. & Piciulo, P. L.
System: The UNT Digital Library
Radiation damage in silicon due to albedo neutrons emitted from hadronic beam dumps (Fe and U) (open access)

Radiation damage in silicon due to albedo neutrons emitted from hadronic beam dumps (Fe and U)

Calculations have been carried out to determine the level of radiation damage that can be expected from albedo neutrons when 1- and 5-GeV negative pions are incident on iron and uranium beam dumps. The calculated damage data are presented in several ways including neutron fluence above 0.111 MeV, 1 MeV equivalent neutron fluence, damage energy deposition, and DPA or displacements per atom. Details are presented as to the method of calculation. 14 refs., 1 fig., 1 tab.
Date: January 1, 1987
Creator: Gabriel, T. A. & Bishop, B. L.
System: The UNT Digital Library
Radial Wire Drift Chambers for CDF Forward Tracking (open access)

Radial Wire Drift Chambers for CDF Forward Tracking

We describe the design, construction, and operating experience of unique drift chambers with radially strung wires for the Collider Detector of Fermilab (CDF) [1] which cover forward ad backward cone angles between 2{sup o} and 10{sup o} and 170{sup o} to 178{sup o}. The chambers are capable of operating in our high rate and high track multiplicity environment with excellent multitrack resolution of 2-3 mm and high tracking accuracy of 140 {micro}m per wire. Results from the recent running experience will be presented.
Date: August 1, 1987
Creator: Atac, M.; Foster, G. W.; Newman-Holmes, C.; Para, A.; Patrick, J.; Sekiguchi, M. et al.
System: The UNT Digital Library
Expectations for direct photon physics from Fermilab experiment E705 (open access)

Expectations for direct photon physics from Fermilab experiment E705

The E705 scintillation glass/lead glass electromagnetic calorimeter is described. The trigger used for recording high transverse momentum direct photon signals from 300 GeV/c ..pi../sup /minus//, ..pi../sup +/, /bar p/, p interactions in a Li/sup 7/ target is explained. Preliminary results on the response of this direct photon trigger and electromagnetic calorimeter and expected event sensitivities are presented. 14 refs., 9 figs., 2 tabs.
Date: November 1, 1987
Creator: Wagoner, D. E.; Arenton, M.; Chen, T. Y.; Conetti, S.; Cox, B.; Delchamps, S. et al.
System: The UNT Digital Library
Elements of a national emergency response system for nuclear accidents (open access)

Elements of a national emergency response system for nuclear accidents

The purpose of this paper is to suggest elements for a general emergency response system, employed at a national level, to detect, evaluate and assess the consequences of a radiological atmospheric release occurring within or outside of national boundaries. These elements are focused on the total aspect of emergency response ranging from providing an initial alarm to a total assessment of the environmental and health effects. Elements of the emergency response system are described in such a way that existing resources can be directly applied if appropriate; if not, newly developed or an expansion of existing resources can be employed. The major thrust of this paper is toward a philosophical discussion and general description of resources that would be required to implementation. If the major features of this proposal system are judged desirable for implementation, then the next level of detail can be added. The philosophy underlying this paper is preparedness - preparedness through planning, awareness and the application of technology. More specifically, it is establishment of reasonable guidelines including the definition of reference and protective action levels for public exposure to accidents involving nuclear material; education of the public, government officials and the news media; and the application of …
Date: February 10, 1987
Creator: Dickerson, Marvin H.
System: The UNT Digital Library
Computational methods of the Advanced Fluid Dynamics Model (open access)

Computational methods of the Advanced Fluid Dynamics Model

To more accurately treat severe accidents in fast reactors, a program has been set up to investigate new computational models and approaches. The product of this effort is a computer code, the Advanced Fluid Dynamics Model (AFDM). This paper describes some of the basic features of the numerical algorithm used in AFDM. Aspects receiving particular emphasis are the fractional-step method of time integration, the semi-implicit pressure iteration, the virtual mass inertial terms, the use of three velocity fields, higher order differencing, convection of interfacial area with source and sink terms, multicomponent diffusion processes in heat and mass transfer, the SESAME equation of state, and vectorized programming. A calculated comparison with an isothermal tetralin/ammonia experiment is performed. We conclude that significant improvements are possible in reliably calculating the progression of severe accidents with further development.
Date: January 1, 1987
Creator: Bohl, W. R.; Wilhelm, D.; Parker, F. R.; Berthier, J.; Maudlin, P. J.; Schmuck, P. et al.
System: The UNT Digital Library
Investigation of failed Type 410 stainless steel shafts from main steam isolation valves at two operating plants (open access)

Investigation of failed Type 410 stainless steel shafts from main steam isolation valves at two operating plants

Metallurgical investigation were performed on a cracked main steam isolation valve (MSIV) shaft from the Joseph M. Farley Unit No. 1 station and two MSIV shafts from the R.E. Ginna Station (only one shaft cracked). This investigation consisted of optical microscopy, chemical analysis, hardness testing, scanning electron microscopy and energy dispersive spectroscopy. The shafts were manufactured from ASTM A276, Type 410 stainless steel in the quenched and tempered condition. The crack on the Farley shaft ran longitudinally and was approximately 16.7 cm (6.6 inches) in length. The crack on the Ginna shaft was approximately 7.6 cm (3 inches) in length and ran almost perpendicularly to the shaft's long axis. The second Ginna shaft had no visible cracks. Hardness measurements of the shafts revealed that the Farley shaft hardness values ranged between R/sub c/ 41 to 44.5, the cracked Ginna shaft values ranged between R/sub c/ 42.9 to 45, while the uncracked shaft's hardness was R/sub c/ 36 to 44.6. The cracks were intergranular and occurred on prior austenite grain boundaries. No evidence of corrosive species or fatigue contribution was seen. This cracking is considered to be an intergranular stress corrosion cracking phenomenon resulting from a high hardness/susceptible material in a …
Date: January 1, 1987
Creator: Czajkowski, C. J.
System: The UNT Digital Library
Preparation and benchmarking of ANSL-V cross sections for advanced neutron source reactor studies (open access)

Preparation and benchmarking of ANSL-V cross sections for advanced neutron source reactor studies

Validity of selected data from the fine-group neutron library was satisfactorily tested in performance parameter calculations for the BAPL-1, TRX-1, and ZEEP-1 thermal lattice benchmarks. BAPL-2 is an H/sub 2/O moderated, uranium oxide lattice; TRX-1 is an H/sub 2/O moderated, 1.31 weight percent enriched uranium metal lattice; ZEEP-1 is a D/sub 2/O-moderated, natural uranium lattice. 26 refs., 1 tab.
Date: January 1, 1987
Creator: Arwood, J. W.; Ford, W. E., III; Greene, N. M.; Primm, R. T., III; Waddell, M. W.; Webster, C. C. et al.
System: The UNT Digital Library
Fermilab Industrial Affiliates roundtable on research technology in the twenty-first century (open access)

Fermilab Industrial Affiliates roundtable on research technology in the twenty-first century

This collection of articles presents views on the future of physics research by leading experts in the field. Topics discussed include particle physics, the Superconducting Super Collider, and the development of new superconducting materials. The articles have been abstracted and indexed separately.
Date: May 1, 1987
Creator: Carrigan, R. A., Jr. & Fenner, R. B.
System: The UNT Digital Library
A hierarchical data-driven model for multi-grid problem solving (open access)

A hierarchical data-driven model for multi-grid problem solving

The data-driven principles of execution present an elegant solution to the problem of instruction scheduling in large scale multiprocessor systems. However, much overhead must be expanded in detecting the simplest forms of parallelism such as vector operations. A two-level architecture with powerful processors is presented here. In addition, preemptive execution of certain actors allows better pipelining and tolerance to latencies. The natural application of the machine to numerical computations is demonstrated by the use of a multi-grid Partial Differential Equation solver.
Date: December 31, 1987
Creator: Najjar, W. & Gaudiot, J.-L.
System: The UNT Digital Library
Advances in technology for the construction of deep-underground facilities (open access)

Advances in technology for the construction of deep-underground facilities

The workshop was organized in order to address technological issues important to decisions regarding the feasibility of strategic options. The objectives of the workshop were to establish the current technological capabilities for deep-underground construction, to project those capabilities through the compressed schedule proposed for construction, and to identify promising directions for timely allocation of existing research and development resources. The earth has been used as a means of protection and safekeeping for many centuries. Recently, the thickness of the earth cover required for this purpose has been extended to the 2,000- to 3,000-ft range in structures contemplated for nuclear-waste disposal, energy storage, and strategic systems. For defensive missile basing, it is now perceived that the magnitude of the threat has increased through better delivery systems, larger payloads, and variable tactics of attack. Thus, depths of 3,000 to 8,000 ft are being considered seriously for such facilities. Moreover, it appears desirable that the facilities be operational (if not totally complete) for defensive purposes within a five-year construction schedule. Deep excavations such as mines are similar in many respects to nearsurface tunnels and caverns for transit, rail, sewer, water, hydroelectric, and highway projects. But the differences that do exist are significant. Major …
Date: December 31, 1987
Creator: unknown
System: The UNT Digital Library
Ceramic characterization (open access)

Ceramic characterization

Objective of this task is to measure and characterize the ceramic properties (crystalline phase composition, grain boundaries, residual stresses) of a series of standard ceramic specimens to assist in developing international standards for ceramic characterization. This report describes electron microscopy of the microstructure and grain boundaries of ESK silicon carbide; supporting x-ray diffraction data for the bulk phase composition is included.
Date: December 31, 1987
Creator: Vaudin, M. D.; Fuller, E. R. Jr.; Cline, J. P. & Dragoo, A. L.
System: The UNT Digital Library
Capacitive charge division in centroid finding cathode readouts in MWPCs. Revision 1/93 (open access)

Capacitive charge division in centroid finding cathode readouts in MWPCs. Revision 1/93

A technique is described in which the centroid of induced charge on cathode strips in a proportional chamber can be determined with reduced differential and integral nonlinearity, without increasing the number of readout channels. It is based on capacitive charge division from intermediate cathode strips to adjacent readout strips, and may be applied to a variety of position readout principles.
Date: October 1, 1987
Creator: Smith, G. C.; Fischer, J. & Radeka, V.
System: The UNT Digital Library
Soft x-ray laser microscopy (open access)

Soft x-ray laser microscopy

Microscopes based on soft X-ray lasers possess unique advantages in bridging the gap between high resolution electron microscopy of dehydrated, stained cells and light microscopy at comparatively low resolution of unaltered live cells. The high brightness and short pulse duration of soft X-ray lasers make them ideal for flash imaging of live specimens. The Princeton soft X-ray laser is based on a magnetically confined laser produced carbon plasma. Radiation cooling after the laser pulse produces rapid recombination which produces a population inversion and high gain. A full account is given in a companion paper in this volume. The important characteristics of the laser beam produced by this device are 1 to 3 mJ of 18.2 nm radiation in a 10 to 30 nsec pulse with a divergence of 5 mrad. The 18.2 nm wavelength, while outside the water window, does provide a factor of 3 difference in absorption coefficients between oxygen and carbon.
Date: December 31, 1987
Creator: DiCicco, D.; Meixler, L.; Skinner, C. H.; Suckewer, S.; Hirschberg, J. & Kohen, E.
System: The UNT Digital Library
Luminance in computer-aided lighting design (open access)

Luminance in computer-aided lighting design

Traditionally, the lighting engineering community has emphasized illuminance, the amount of light reaching a surface, as the primary design goal. The Illuminating Engineering Society (IES) provides tables of illuminances for different types of tasks which lighting engineers consult in designing lighting systems. Illuminance has proven to be a popular metric because it corresponds closely to the amount of energy needed to light a building as well as the initial cost of the lighting system. Perhaps more importantly, illuminance is easy to calculate, especially in simple unobstructed spaces with direct lighting. However,illuminance is not well correlated with visual performance, which is the real reason for installing a lighting system in the first place. Visual performance is a psychophysiological quantity that has been tied to physical quantities such as contrast, size and adaptation level by subject experiments. These physical quantities can be approximated from illuminance using a host of assumptions about the environment, or derived directly from the distribution of luminance. Luminance is the quantity of light traveling through a point in a certain direction, and it is this quantity that the eye actually ``sees``. However, the difficulty of calculating luminance for common tasks has made it an unpopular metric. Despite its …
Date: August 1, 1987
Creator: Ward, G. J.; Rubinstein, F. M. & Grynberg, A.
System: The UNT Digital Library
Beamstrahlung monitors at SLC (open access)

Beamstrahlung monitors at SLC

Some properties of beamstrahlung are discussed, and plans to observe the effect at SLC by the use of Cherenkov counters are illustrated.
Date: March 1, 1987
Creator: Field, R. C.
System: The UNT Digital Library
Probability of causation: Implications for radiological protection and dose limitation (open access)

Probability of causation: Implications for radiological protection and dose limitation

This report on the probability of causation of radiation-induced cancer is an attempt to bring together biology, chemistry, physics and statistics to calculate a value in the form of a ratio expressed as a percentage. In involves the interactions of numerous cancer risk factors, and all are fraught with technical difficulties and uncertainties. It is a computational approach to a societal problem that should be resolved in the political arena by men and women of government and law. But, it must be examined, because at the present, we have no reasonable method to explain the complexity of the mechanism of radiation-induced cancer and the probability of injury to an individual exposed in the past to ionizing radiation, and because society does not know how to compensate such a person who may have been injured by radiation, and particularly low-level radiation. Five questions are discussed that concern probability of causation of radiation-induced cancer. First, what is it and how can we best define the concept? Second, what are the methods of estimation and cancer causation? Third, what are the uncertainties involved? Fourth, what are the strengths and limitation of the computational approach? And fifth, what are the implications for radiological protection …
Date: May 1, 1987
Creator: Fabrikant, J. I.
System: The UNT Digital Library
A model of the circulating blood for use in radiation dose calculations (open access)

A model of the circulating blood for use in radiation dose calculations

Over the last few years there has been a significant increase in the use of radionuclides in leukocyte, platelet, and erythrocyte imaging procedures. Radiopharmaceutical used in these procedures are confined primarily to the blood, have short half-lives, and irradiate the body as they move through the circulatory system. There is a need for a model, to describe the circulatory system in an adult human, which can be used to provide radiation absorbed dose estimates for these procedures. A simplified model has been designed assuming a static circulatory system and including major organs of the body. The model has been incorporated into the MIRD phantom and calculations have been completed for a number of exposure situations and radionuclides of clinical importance. The model will be discussed in detail and results of calculations using this model will be presented.
Date: December 31, 1987
Creator: Hui, T. E. & Poston, J. W., Sr.
System: The UNT Digital Library
Birch's Law for fluid metals (open access)

Birch's Law for fluid metals

By comparing acoustic velocities in fluid metals over a very wide range of densities we have established Birch's Law as an approximate representation over the entire liquid range. For a given liquid metal the acoustic velocity is close to linear in density, with a slope determined by the atomic weight. The measurements include isobaric expansion to less than half normal density, ultrasonics on molten metals at 1 atmosphere, and shock melted metals to greater than twice normal density.
Date: January 1, 1987
Creator: Shaner, J. W.; Hixson, R. S.; Winkler, M. A.; Boness, D. A. & Brown, J. M.
System: The UNT Digital Library
Pion charge-exchange reactions: The analog state transitions (open access)

Pion charge-exchange reactions: The analog state transitions

The general features of pion charge-exchange reactions leading to nuclear-isobaric-analog states (IAS) and double-isobaric-analog states (DIAS), as they have emerged from studies over the past ten years, are reviewed. The energy range investigated is 20 to 550 MeV for IAS transitions and 20 to 300 MeV for DIAS transitions. These data are seen to play an important role in characterizing the pion optical potential, in determining the ..delta..-N interaction in nuclei, and in the study of nucleon correlations in nuclei. Recent progress achieved in understanding the role of such correlations in double-charge-exchange reactions is reviewed. 55 refs., 43 figs., 3 tabs.
Date: January 1, 1987
Creator: Baer, H.W.
System: The UNT Digital Library
Performance correlations for high temperature potassium heat pipes (open access)

Performance correlations for high temperature potassium heat pipes

Potassium heat pipes designed for operation at a nominal temperature of 775K have been developed for use in a heat pipe cooled reactor design. The heat pipes operate in a gravity assist mode with a maximum required power throughput of approximately 16 kW per heat pipe. Based on a series of sub-scale experiments with 2.12 and 3.2 cm diameter heat pipes the prototypic heat pipe diameter was set at 5.7 cm with a simple knurled wall wick used in the interests of mechanical simplicity. The performance levels required for this design had been demonstrated in prior work with gutter assisted wicks and emphasis in the present work was on the attainment of similar performance with a simplified wick structure. The wick structure used in the experiment consisted of a pattern of knurled grooves in the internal wall of the heat pipe. The knurl depth required for the planned heat pipe performance was determined by scaling of wick characteristic data from the sub-scale tests. These tests indicated that the maximum performance limits of the test heat pipes did not follow normal entrainment limit predictions for textured wall gravity assist heat pipes. Test data was therefore scaled to the prototype design based …
Date: January 1, 1987
Creator: Merrigan, M.A.; Keddy, E.S. & Sena, J.T.
System: The UNT Digital Library
Microanalysis of polytypoid ceramics by imaging, diffraction and spectroscopy (open access)

Microanalysis of polytypoid ceramics by imaging, diffraction and spectroscopy

Combined atomic resolution imaging, microdiffraction and energy dispersive x-ray microanalysis suggest that the 32H polytypoid in the AlN-Al/sub 2/O/sub 3/ pseudobinary system is in fact a 7:9 periodic intergrowth of the 21R and 27R polytypoids. Furthermore, these combined techniques verify that the cation/anion ratio is 16/17 and that this ratio defines the polytypoid precisely.
Date: February 1, 1987
Creator: Krishnan, K.M. & Thomas, G.
System: The UNT Digital Library
Status of ECR (Electron Cyclotron Resonance) source technology (open access)

Status of ECR (Electron Cyclotron Resonance) source technology

ECR (Electron Cyclotron Resonance) ion sources are now in widespread use for the production of high quality multiply charged ion beams for accelerators and atomic physics experiments, and industrial applications are being explored. Several general characteristics of ECR sources explain their widespread acceptance. For use with cyclotrons which require CW multiply charged ion beams, the ECR source has many advantages over heavy-ion PIG sources. Most important is the ability to produce higher charge states at useful intensities for nuclear physics experiments. Since the maximum energy set by the bending limit of a cyclotron scales with the square of the charge state, the installation of ECR sources on cyclotrons has provided an economical path to raise the energy. Another characteristic of ECR sources is that the discharge is produced without cathodes, so that only the source material injected into an ECR source is consumed. As a result, ECR sources can be operated continuously for periods of weeks without interruption. Techniques have been developed in the last few years, which allow these sources to produce beams from solid materials. The beam emittance from ECR sources is in the range of 50 to 200 ..pi.. mm-mrad at 10 kV. The principles of ECR …
Date: March 1, 1987
Creator: Lyneis, C.M.
System: The UNT Digital Library