Some tools of the trade we`ve developed for our cross-section calculations (open access)

Some tools of the trade we`ve developed for our cross-section calculations

A number of compute codes have been modified or developed, both main-frame and PC. Seven codes, of which three are discussed in some detail. The later are: a controller-driven, double-precision version of the coupled-channel code ECIS; the latest version of STAPRE, a precompound plus Hauser-Feshbach nuclear reaction code; and NUSTART, a PC code that analyzes large sets of discrete nuclear levels and the multipole transitions among them. All main-frame codes are now being converted to the UNICOS operating system.
Date: November 1, 1992
Creator: Gardner, D. G. & Gardner, M. A.
Object Type: Article
System: The UNT Digital Library
The operational status of the Booster injector for the AGS accelerator complex at BNL (open access)

The operational status of the Booster injector for the AGS accelerator complex at BNL

The Booster synchrotron at Brookhaven National Laboratory has been incorporated into the accelerator chain at the Alternating Gradient Synchrotron (AGS) complex. After a successful first commissioning effort in the spring of 1991, the Booster has been part of this year`s silicon, gold and proton physics runs. After a brief review of the Booster design goals, and of the early commissioning, this paper will summarize this year`s activities.
Date: September 1, 1992
Creator: Ahrens, L.; Bleser, E.; Brennan, J. M.; Gardner, C.; Gill, E.; Glenn, J. W. et al.
Object Type: Article
System: The UNT Digital Library
The operational status of the Booster injector for the AGS accelerator complex at BNL (open access)

The operational status of the Booster injector for the AGS accelerator complex at BNL

The Booster synchrotron at Brookhaven National Laboratory has been incorporated into the accelerator chain at the Alternating Gradient Synchrotron (AGS) complex. After a successful first commissioning effort in the spring of 1991, the Booster has been part of this year's silicon, gold and proton physics runs. After a brief review of the Booster design goals, and of the early commissioning, this paper will summarize this year's activities.
Date: January 1, 1992
Creator: Ahrens, L.; Bleser, E.; Brennan, J. M.; Gardner, C.; Gill, E.; Glenn, J. W. et al.
Object Type: Article
System: The UNT Digital Library
Flue gas desulfurization by rotating beds (open access)

Flue gas desulfurization by rotating beds

The operating and mass transfer characteristics of rotating foam metal beds were studied to determine the potential for flue gas desulfurization. This is a final technical report on the work supported by DOE [number sign]FG22-87-PC79924. The report is divided into two sections, Part 1 deals primarily with the operating characteristics of rotating beds, and Part 2 covers the mass transfer characteristics of S0[sub 2] absorption in water-lime slurries. Rotating foam metal beds are in essence packed towers operated in high gravitational fields. The foam metal bed is in the form of a cylindrical donut, or torus, and is rotated to produced the high centrifugal forces. The liquid phase enters the bed at the inner surface of the torus and is pulled by the field through the bed. Gas flows countercurrent to the liquid. The bed packing can have a very large specific surface areas and not flood. Possible benefits include much smaller height of a transfer unit resulting in smaller equipment and supporting structures, reduced solvent inventory, faster response with improved process control, reduced pressure drop, and shorter startup and shut-down times. This work is concerned broadly with the operating characteristics of rotating beds, the objectives being to (1) determine …
Date: January 1, 1992
Creator: Gardner, N.; Keyvani, M. & Coskundeniz, A.
Object Type: Report
System: The UNT Digital Library
Flue gas desulfurization by rotating beds. Final technical report (open access)

Flue gas desulfurization by rotating beds. Final technical report

The operating and mass transfer characteristics of rotating foam metal beds were studied to determine the potential for flue gas desulfurization. This is a final technical report on the work supported by DOE {number_sign}FG22-87-PC79924. The report is divided into two sections, Part 1 deals primarily with the operating characteristics of rotating beds, and Part 2 covers the mass transfer characteristics of S0{sub 2} absorption in water-lime slurries. Rotating foam metal beds are in essence packed towers operated in high gravitational fields. The foam metal bed is in the form of a cylindrical donut, or torus, and is rotated to produced the high centrifugal forces. The liquid phase enters the bed at the inner surface of the torus and is pulled by the field through the bed. Gas flows countercurrent to the liquid. The bed packing can have a very large specific surface areas and not flood. Possible benefits include much smaller height of a transfer unit resulting in smaller equipment and supporting structures, reduced solvent inventory, faster response with improved process control, reduced pressure drop, and shorter startup and shut-down times. This work is concerned broadly with the operating characteristics of rotating beds, the objectives being to (1) determine the …
Date: December 1, 1992
Creator: Gardner, Nelson; Keyvani, Majid & Coskundeniz, Aydin
Object Type: Report
System: The UNT Digital Library
Postirradiation deformation behavior in ferritic Fe-Cr alloys (open access)

Postirradiation deformation behavior in ferritic Fe-Cr alloys

It has been demonstrated that fast-neutron irradiation produces significant hardening in simple Fe-(3-18)Cr binary alloys irradiated to about 35 dpa in the temperature range 365 to 420{degrees}C, whereas irradiation at 574{degrees}C produces hardening only for 15% or more chromium. The irradiation-induced changes in tensile properties are discussed in terms of changes in the power law work-hardening exponent. The work-hardening exponent of the lower chromium alloys decreased significantly after low-temperature irradiation ({le} 420{degrees}C) but increased after irradiation at 574{degrees}C. The higher chromium alloys failed either in cleavage or in a mixed ductile/brittle fashion. Deformation microstructures are presented to support the tensile behavior.
Date: June 1, 1992
Creator: Hamilton, M. L.; Gelles, D. S. & Gardner, P. L.
Object Type: Article
System: The UNT Digital Library
Postirradiation deformation behavior in ferritic Fe-Cr alloys (open access)

Postirradiation deformation behavior in ferritic Fe-Cr alloys

It has been demonstrated that fast-neutron irradiation produces significant hardening in simple Fe-(3-18)Cr binary alloys irradiated to about 35 dpa in the temperature range 365 to 420[degrees]C, whereas irradiation at 574[degrees]C produces hardening only for 15% or more chromium. The irradiation-induced changes in tensile properties are discussed in terms of changes in the power law work-hardening exponent. The work-hardening exponent of the lower chromium alloys decreased significantly after low-temperature irradiation ([le] 420[degrees]C) but increased after irradiation at 574[degrees]C. The higher chromium alloys failed either in cleavage or in a mixed ductile/brittle fashion. Deformation microstructures are presented to support the tensile behavior.
Date: June 1, 1992
Creator: Hamilton, M. L.; Gelles, D. S. & Gardner, P. L.
Object Type: Article
System: The UNT Digital Library
Use of the Edmonds-Reilly Model to model energy-sector impacts of greenhouse gas emissions control strategies (open access)

Use of the Edmonds-Reilly Model to model energy-sector impacts of greenhouse gas emissions control strategies

The purpose of this paper is to document the results of our application of the Edmonds-Reilly Model (ERM) using several scenarios provided in connection with the 1991 Energy Modeling Forum (EMF). The purpose of this session of the forum is to compare the efforts of several modeling teams using common assumptions to examine the energy sector impacts of strategies to control greenhouse gas emissions. Because the output of this exercise is data-rich, most of this exposition is in graphical form with the narrative serving mainly as a roadmap for moving from one highlight to the next. The following sessions briefly describe the model and some of the special modifications made for this effort. The case-by-case discussion is contained in Section IV, followed by a summary of the potential pitfalls involved in attempting to assess the cost of emissions reduction from the model data.
Date: January 1, 1992
Creator: Barns, D. W.; Edmonds, J. A. & Reilly, J. M.
Object Type: Report
System: The UNT Digital Library
Use of the Edmonds-Reilly Model to model energy-sector impacts of greenhouse gas emissions control strategies (open access)

Use of the Edmonds-Reilly Model to model energy-sector impacts of greenhouse gas emissions control strategies

The purpose of this paper is to document the results of our application of the Edmonds-Reilly Model (ERM) using several scenarios provided in connection with the 1991 Energy Modeling Forum (EMF). The purpose of this session of the forum is to compare the efforts of several modeling teams using common assumptions to examine the energy sector impacts of strategies to control greenhouse gas emissions. Because the output of this exercise is data-rich, most of this exposition is in graphical form with the narrative serving mainly as a roadmap for moving from one highlight to the next. The following sessions briefly describe the model and some of the special modifications made for this effort. The case-by-case discussion is contained in Section IV, followed by a summary of the potential pitfalls involved in attempting to assess the cost of emissions reduction from the model data.
Date: January 1, 1992
Creator: Barns, D. W.; Edmonds, J. A. & Reilly, J. M.
Object Type: Report
System: The UNT Digital Library
Use of the Edmonds-Reilly Model to model energy-related greenhouse gas emissions (open access)

Use of the Edmonds-Reilly Model to model energy-related greenhouse gas emissions

The purpose of this paper is to document the results of our application of the Edmonds-Reilly Model (ERM) using several scenarios provided for an Organization for Economic Cooperation and Development (OECD) project comparing global models. Because the output of this exercise is data-rich, most of this exposition is in graphical form, with the narrative serving mainly as a roadmap for moving from one highlight to the next. The first two sections of the paper briefly describe the model and some of the special modifications made for this effort. The case-by-case discussion is contained in Section IV, followed by a summary of the potential pitfalls involved in attempting to assess the cost of emissions reduction from the model data.
Date: January 1, 1992
Creator: Barns, D. W.; Edmonds, J. A. & Reillyn, J. M.
Object Type: Report
System: The UNT Digital Library
Use of the Edmonds-Reilly Model to model energy-related greenhouse gas emissions (open access)

Use of the Edmonds-Reilly Model to model energy-related greenhouse gas emissions

The purpose of this paper is to document the results of our application of the Edmonds-Reilly Model (ERM) using several scenarios provided for an Organization for Economic Cooperation and Development (OECD) project comparing global models. Because the output of this exercise is data-rich, most of this exposition is in graphical form, with the narrative serving mainly as a roadmap for moving from one highlight to the next. The first two sections of the paper briefly describe the model and some of the special modifications made for this effort. The case-by-case discussion is contained in Section IV, followed by a summary of the potential pitfalls involved in attempting to assess the cost of emissions reduction from the model data.
Date: January 1, 1992
Creator: Barns, D. W.; Edmonds, J. A. & Reillyn, J. M.
Object Type: Report
System: The UNT Digital Library
Results of Geothermal Gradient Core Hole TCB-1, Tecuamburro Volcano Geothermal Site, Guatemala, Central America (open access)

Results of Geothermal Gradient Core Hole TCB-1, Tecuamburro Volcano Geothermal Site, Guatemala, Central America

Results of geological, volcanological, hydrogeochemical, and geophysical field studies conducted in 1988 and 1989 at the Tecuamburro volcano geothermal site in Guatemala indicated that there is a substantial shallow heat source beneath the area of youngest volcanism. To obtain information on subsurface temperatures and temperature gradients, stratigraphy, hydrothermal alteration, fracturing, and possible inflows of hydrothermal fluids, a geothermal gradient core hole (TCB-1) was drilled to 808 m low on the northern flank of the Tecuamburro volcano Complex, 300 km south of a 300-m-diameter phreatic crater, Laguna Ixpaco, dated at 2,910 years. Gases from acid-sulfate springs near Laguna Ixpaco consistently yield maximum estimated subsurface temperatures of 250--300{degrees}C. The temperature versus depth curve from TCB-1 does not show isothermal conditions and the calculated thermal gradients from 500--800 m is 230{degrees}C/km. Bottom hole temperature is 238{degrees}C. Calculated heat flow values are nearly 9 heat flow units (HFU). The integration of results from the TCB-1 gradient core hole with results from field studies provides strong evidence that the Tecuamburro area holds great promise for containing a commercial geothermal resource.
Date: February 1, 1992
Creator: Adams, A. I.; Chipera, S.; Counce, D.; Gardner, J.; Goff, S.; Goff, F. et al.
Object Type: Report
System: The UNT Digital Library
Shock tube kinetic study of the CH sub 3 + H sub 2 r equilibrium H + CH sub 4 reaction and the methane dissociation reaction (open access)

Shock tube kinetic study of the CH sub 3 + H sub 2 r equilibrium H + CH sub 4 reaction and the methane dissociation reaction

In this kinetic study of (1) the reaction of CH{sub 3} radicals with H{sub 2} and (2) the thermal dissociation of methane, primary product H atoms were monitored directly using the sensitive atomic resonance absorption detection technique. The detection limit for the (H) was about 3{times}10{sup 10} atoms cm{sup {minus}3}. Rate constants for both reactions were obtained under pseudo-first-order conditions. In addition, computer simulations verified that kinetic complications were avoided. For the reaction of CH{sub 3}+H{sub 2}, experiments were performed using either acetone or ethane to generate CH{sub 3} radicals rapidly by thermal dissociation in argon. Twenty-four experiments were performed over the temperature range 1346K to 1793K and a rate constant expression derived using linear least-squares analysis: k{sub {minus}2}(T) = (6.0{plus minus}0.7){times}10{sup {minus}12} exp ({minus}5920{plus minus}190K/T) cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. 46 refs., 5 figs., 5 tabs.
Date: January 1, 1992
Creator: Klemm, R.B.; Sutherland, J.W. & Tao, Wen.
Object Type: Article
System: The UNT Digital Library
Shock tube kinetic study of the CH{sub 3} + H{sub 2} {r_equilibrium} H + CH{sub 4} reaction and the methane dissociation reaction (open access)

Shock tube kinetic study of the CH{sub 3} + H{sub 2} {r_equilibrium} H + CH{sub 4} reaction and the methane dissociation reaction

In this kinetic study of (1) the reaction of CH{sub 3} radicals with H{sub 2} and (2) the thermal dissociation of methane, primary product H atoms were monitored directly using the sensitive atomic resonance absorption detection technique. The detection limit for the [H] was about 3{times}10{sup 10} atoms cm{sup {minus}3}. Rate constants for both reactions were obtained under pseudo-first-order conditions. In addition, computer simulations verified that kinetic complications were avoided. For the reaction of CH{sub 3}+H{sub 2}, experiments were performed using either acetone or ethane to generate CH{sub 3} radicals rapidly by thermal dissociation in argon. Twenty-four experiments were performed over the temperature range 1346K to 1793K and a rate constant expression derived using linear least-squares analysis: k{sub {minus}2}(T) = (6.0{plus_minus}0.7){times}10{sup {minus}12} exp ({minus}5920{plus_minus}190K/T) cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. 46 refs., 5 figs., 5 tabs.
Date: February 1, 1992
Creator: Klemm, R. B.; Sutherland, J. W. & Tao, Wen
Object Type: Article
System: The UNT Digital Library
AMPX-77: A modular code system for generating coupled multigroup neutron-gamma cross-section libraries from ENDF/B-IV and/or ENDF/B-V (open access)

AMPX-77: A modular code system for generating coupled multigroup neutron-gamma cross-section libraries from ENDF/B-IV and/or ENDF/B-V

AMPX-77 is a modular system of computer programs that pertain to nuclear analyses, with a primary emphasis on tasks associated with the production and use of multigroup cross sections. AH basic cross-section data are to be input in the formats used by the Evaluated Nuclear Data Files (ENDF/B), and output can be obtained in a variety of formats, including its own internal and very general formats, along with a variety of other useful formats used by major transport, diffusion theory, and Monte Carlo codes. Processing is provided for both neutron and gamma-my data. The present release contains codes all written in the FORTRAN-77 dialect of FORTRAN and wig process ENDF/B-V and earlier evaluations, though major modules are being upgraded in order to process ENDF/B-VI and will be released when a complete collection of usable routines is available.
Date: October 1, 1992
Creator: Greene, N. M.; Ford, W. E., III; Petrie, L. M. & Arwood, J. W.
Object Type: Report
System: The UNT Digital Library
AMPX-77: A modular code system for generating coupled multigroup neutron-gamma cross-section libraries from ENDF/B-IV and/or ENDF/B-V (open access)

AMPX-77: A modular code system for generating coupled multigroup neutron-gamma cross-section libraries from ENDF/B-IV and/or ENDF/B-V

AMPX-77 is a modular system of computer programs that pertain to nuclear analyses, with a primary emphasis on tasks associated with the production and use of multigroup cross sections. AH basic cross-section data are to be input in the formats used by the Evaluated Nuclear Data Files (ENDF/B), and output can be obtained in a variety of formats, including its own internal and very general formats, along with a variety of other useful formats used by major transport, diffusion theory, and Monte Carlo codes. Processing is provided for both neutron and gamma-my data. The present release contains codes all written in the FORTRAN-77 dialect of FORTRAN and wig process ENDF/B-V and earlier evaluations, though major modules are being upgraded in order to process ENDF/B-VI and will be released when a complete collection of usable routines is available.
Date: October 1, 1992
Creator: Greene, N. M.; Ford, W. E., III; Petrie, L. M. & Arwood, J. W.
Object Type: Report
System: The UNT Digital Library
Osiris and SOMBRERO inertial confinement fusion power plant designs. Volume 2, Designs, assessments, and comparisons, Final report (open access)

Osiris and SOMBRERO inertial confinement fusion power plant designs. Volume 2, Designs, assessments, and comparisons, Final report

The primary objective of the of the IFE Reactor Design Studies was to provide the Office of Fusion Energy with an evaluation of the potential of inertial fusion for electric power production. The term reactor studies is somewhat of a misnomer since these studies included the conceptual design and analysis of all aspects of the IFE power plants: the chambers, heat transport and power conversion systems, other balance of plant facilities, target systems (including the target production, injection, and tracking systems), and the two drivers. The scope of the IFE Reactor Design Studies was quite ambitious. The majority of our effort was spent on the conceptual design of two IFE electric power plants, one using an induction linac heavy ion beam (HIB) driver and the other using a Krypton Fluoride (KrF) laser driver. After the two point designs were developed, they were assessed in terms of their (1) environmental and safety aspects; (2) reliability, availability, and maintainability; (3) technical issues and technology development requirements; and (4) economics. Finally, we compared the design features and the results of the assessments for the two designs.
Date: March 1, 1992
Creator: Meier, W. R.; Bieri, R. L. & Monsler, M. J.
Object Type: Report
System: The UNT Digital Library
The extraction of bitumen from western tar sands. Annual report, July 1990--July 1991 (open access)

The extraction of bitumen from western tar sands. Annual report, July 1990--July 1991

Contents of this report include the following: executive summary; characterization of the native bitumen from the Whiterocks oil sand deposit; influence of carboxylic acid content on bitumen viscosity; water based oil sand separation technology; extraction of bitumen from western oil sands by an energy-efficient thermal method; large- diameter fluidized bed reactor studies; rotary kiln pyrolysis of oil sand; catalytic upgrading of bitumen and bitumen derived liquids; ebullieted bed hydrotreating and hydrocracking; super critical fluid extraction; bitumen upgrading; 232 references; Appendix A--Whiterocks tar sand deposit bibliography; Appendix B--Asphalt Ridge tar sand deposit bibliography; and Appendix C--University of Utah tar sands bibliography.
Date: April 1, 1992
Creator: Oblad, A. G.; Bunger, J. W.; Deo, M. D.; Hanson, F. V.; Miller, J. D. & Seader, J. D.
Object Type: Report
System: The UNT Digital Library
The Extraction of Bitumen From Western Oil Sands. Annual Report, July 1991--July 1992 (open access)

The Extraction of Bitumen From Western Oil Sands. Annual Report, July 1991--July 1992

The University of Utah tar sand research and development program is concerned with research and development on Utah is extensive oil sands deposits. The program has been intended to develop a scientific and technological base required for eventual commercial recovery of the heavy oils from oil sands and processing these oils to produce synthetic crude oil and other products such as asphalt. The overall program is based on mining the oil sand, processing the mined sand to recover the heavy oils and upgrading them to products. Multiple deposits are being investigated since it is believed that a large scale (approximately 20,000 bbl/day) plant would require the use of resources from more than one deposit. The tasks or projects in the program are organized according to the following classification: Recovery technologies which includes thermal recovery methods, water extraction methods, and solvent extraction methods; upgrading and processing technologies which covers hydrotreating, hydrocracking, and hydropyrolysis; solvent extraction; production of specialty products; and environmental aspects of the production and processing technologies. These tasks are covered in this report.
Date: August 1, 1992
Creator: Oblad, A. G.; Bunger, J. W.; Dahlstrom, D. A.; Deo, M. D.; Hanson, F. V.; Miller, J. D. et al.
Object Type: Report
System: The UNT Digital Library
National profile on commercially generated low-level radioactive mixed waste (open access)

National profile on commercially generated low-level radioactive mixed waste

This report details the findings and conclusions drawn from a survey undertaken as part of a joint US Nuclear Regulatory Commission and US Environmental Protection Agency-sponsored project entitled ``National Profile on Commercially Generated Low-Level Radioactive Mixed Waste.`` The overall objective of the work was to compile a national profile on the volumes, characteristics, and treatability of commercially generated low-level mixed waste for 1990 by five major facility categories-academic, industrial, medical, and NRC-/Agreement State-licensed goverment facilities and nuclear utilities. Included in this report are descriptions of the methodology used to collect and collate the data, the procedures used to estimate the mixed waste generation rate for commercial facilities in the United States in 1990, and the identification of available treatment technologies to meet applicable EPA treatment standards (40 CFR Part 268) and, if possible, to render the hazardous component of specific mixed waste streams nonhazardous. The report also contains information on existing and potential commercial waste treatment facilities that may provide treatment for specific waste streams identified in the national survey. The report does not include any aspect of the Department of Energy`s (DOES) management of mixed waste and generally does not address wastes from remedial action activities.
Date: December 1, 1992
Creator: Klein, J. A.; Mrochek, J. E.; Jolley, R. L.; Osborne-Lee, I. W.; Francis, A. A. & Wright, T.
Object Type: Report
System: The UNT Digital Library
Evaluation and silicon nitride internal combustion engine components. Final report, Phase I (open access)

Evaluation and silicon nitride internal combustion engine components. Final report, Phase I

The feasibility of silicon nitride (Si{sub 3}N{sub 4}) use in internal combustion engines was studied by testing three different components for wear resistance and lower reciprocating mass. The information obtained from these preliminary spin rig and engine tests indicates several design changes are necessary to survive high-stress engine applications. The three silicon nitride components tested were valve spring retainers, tappet rollers, and fuel pump push rod ends. Garrett Ceramic Components` gas-pressure sinterable Si{sub 3}N{sub 4} (GS-44) was used to fabricate the above components. Components were final machined from densified blanks that had been green formed by isostatic pressing of GS-44 granules. Spin rig testing of the valve spring retainers indicated that these Si{sub 3}N{sub 4} components could survive at high RPM levels (9,500) when teamed with silicon nitride valves and lower spring tension than standard titanium components. Silicon nitride tappet rollers showed no wear on roller O.D. or I.D. surfaces, steel axles and lifters; however, due to the uncrowned design of these particular rollers the cam lobes indicated wear after spin rig testing. Fuel pump push rod ends were successful at reducing wear on the cam lobe and rod end when tested on spin rigs and in real-world race applications.
Date: April 1, 1992
Creator: Voldrich, W.
Object Type: Report
System: The UNT Digital Library
Long term modeling of the links between economics, technical progress and environment: Evolution of approaches and new trends (open access)

Long term modeling of the links between economics, technical progress and environment: Evolution of approaches and new trends

This paper examines the evolution of modeling on greenhouse as emissions. The paper briefly highlights the origins and early efforts to model greenhouse gas emissions, efforts subsequent to 1988, and the shape of the next generation of greenhouse gas emissions models. Particular emphasis is placed on the author`s own contributions, including the Edmonds-Reilly Model and the second generation model.
Date: October 1, 1992
Creator: Edmonds, J.
Object Type: Article
System: The UNT Digital Library
Long term modeling of the links between economics, technical progress and environment: Evolution of approaches and new trends (open access)

Long term modeling of the links between economics, technical progress and environment: Evolution of approaches and new trends

This paper examines the evolution of modeling on greenhouse as emissions. The paper briefly highlights the origins and early efforts to model greenhouse gas emissions, efforts subsequent to 1988, and the shape of the next generation of greenhouse gas emissions models. Particular emphasis is placed on the author's own contributions, including the Edmonds-Reilly Model and the second generation model.
Date: October 1, 1992
Creator: Edmonds, J.
Object Type: Article
System: The UNT Digital Library
The oncogenic action of ionizing radiation on rat skin (open access)

The oncogenic action of ionizing radiation on rat skin

The multistage theory of carcinogenesis specifies that cells progress to cancer through a series of discrete, irreversible genetic alterations, but data on radiation-induced cancer incidence in rat skin suggests that an intermediate repairable alteration may occur. Data are presented on cancer induction in rat skin exposed to an electron beam (LET=0.34 keV/[mu]), a neon ion beam (LET=45) or an argon ion beam (LET=125). The rats were observed for tumors at least 78 weeks with squamous and basal cell carcinomas observed. The total cancer yield was fitted by the quadratic equation, and the equation parameters were estimated by linear regression for each type of radiation. Analysis of the DNA from the electron-induced carcinomas indicated that K-ras and/or c-myc oncogenes were activated. In situ hybridization indicated that the cancers contain subpopulations of cells with differing amounts of c-myc and H-ras amplification. The results are consistent with the idea that ionizing radiation produces stable, carcinogenically relevant lesions via 2 repairable events at low LET and via a non-repairable linked event pathway at high LET; either pathway may advance the cell by 1 stage. The proliferative response of rat epidermis following exposure to ionizing radiation was quantified by injection of [sup 14]C-thymidine. The return …
Date: January 1, 1992
Creator: Burns, F. J. & Garte, S. J.
Object Type: Report
System: The UNT Digital Library