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in subjects: "Dose Rates"

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Damage nucleation in Si during ion irradiation

Damage nucleation in single crystals of silicon during ion irradiation is investigated. Experimental results and mechanisms for damage nucleation during both room and liquid nitrogen temperature irradiation with different mass ions are discussed. It is shown that the accumulation of damage during room temperature irradiation depends on the rate of implantation. These dose rate effects are found to decrease in magnitude as the mass of the ions is increased. The significance of dose rate effects … more

Date: January 1, 1984

Creator: Holland, O.W.; Fathy, D. & Narayan, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Radiation dosimetry through spectral definition

We have developed a fieldable instrumentation system for determining from measured flux spectra, both the neutron and gamma ray dose rate distributions associated with radioactive sources. This system includes the sensors, the computer-based data acquisition and analysis hardware, and the requisite software for unfolding the sensor response functions to obtain the flux spectra, and for folding the resultant flux spectra with appropriate flux spectrum-to-dose conversion factors. We use bismuth g… more

Date: January 1, 1985

Creator: Dowdy, E. J.; Moss, C. E.; Robba, A. A.; Evans, A. E.; Lucas, M. C.; Shunk, E. R. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Dose-rate conversion factors for external exposure to photons and electrons

Dose-rate conversion factors for external exposure to photons and electrons have been calculated for approximately 500 radionuclides of potential importance in environmental radiological assessments. The dose-rate factors were obtained using the DOSFACTER computer code. The results given in this report incorporate calculation of electron dose-rate factors for radiosensitive tissues of the skin, improved estimates of organ dose-rate factors for photons, based on organ doses for monoenergetic sou… more

Date: August 1, 1981

Creator: Kocher, David C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Dose-rate models for human survival after exposure to ionizing radiation

This paper reviews new estimates of the L/sub 50/ in man by Mole and by Rotblat, the biological processes contributing to hematologic death, the collection of animal experiments dealing with hematologic death, and the use of regression analysis to make new estimates of human mortality based on all relevant animal studies. Regression analysis of animal mortality data has shown that mortality is dependent strongly on dose rate, species, body weight, and time interval over which the exposure is de… more

Date: January 1, 1986

Creator: Jones, T.D.; Morris, M.D. & Young, R.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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EBT-P gamma-ray shielding system

An elaborate study was carried out for the coil and biological shield of the ELMO Bumpy Torus proof-of-principle (EBT-P) device. A three-dimensional scoping study for the coil shield was performed for four different shielding options to define the heat load for each component and check the compliance with the design criterion of 10 watts maximum heat per coil from the gamma ray sources. Also, a detailed biological dose survey was performed which included: (a) the dose equivalent inside and outs… more

Date: December 1, 1981

Creator: Gohar, Y.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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ACDOS3: a further improved neutron dose-rate code

ACD0S3 is a computer code designed primarily to calculate the activities and dose rates produced by neutron activation in a variety of simple geometries. Neutron fluxes, in up to 50 groups and with energies up to 20 MeV, must be supplied as part of the input data. The neutron-source strength must also be supplied, or alternately, the code will compute it from neutral-beam operating parameters in the case where the source is a fusion-reactor injector. ACD0S3 differs from the previous version ACD… more

Date: July 1, 1982

Creator: Martin, C.S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Sensitivity study of neutron transport through standard and rebar concrete

An investigation is under way at ORNL to (1) develop a data base pertinent to the transport of neutrons through thick concrete shields, (2) use the data base in an energy group boundary selection and collapsing scheme, and (3) develop a simple methodology to access the data base to provide rapid solutions to practical shielding problems. This paper describes work carried out to fulfill objective (1), the work consisting of calculations of the transport of fission neutrons through 1- and 2-m-thi… more

Date: January 1, 1982

Creator: Bhuiyan, S. I.; Roussin, R. W. & Lucius, J. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Dose-rate conversion factors for external exposure to photons and electrons

This paper describes recent modifications of the computer code DOSFACTER, which was developed for the purpose of estimating dose-rate conversion factors for external exposure to photons and electrons emitted by radionuclides dispersed in the environment. The modifications and additions which have been made to the calculations outlined above include the following: (1) calculation of electron dose-rate factors for radiosensitive portions of the skin; (2) incorporation of improved estimates of org… more

Date: January 1, 1980

Creator: Kocher, David C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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ALARA studies on spent fuel and waste casks

In this report, some implications of applying the ALARA concept to cask designs for transporting spent fuel, high-level commercial and defense waste, and remote-handled transuranic waste are investigated. The XSDRNPM, one-dimensional radiation transport code, was used to obtain potential shield designs that would yield total dose rates at 1.8 m from the cask surface of 10, 5, and 2 mrem/h. Gamma shields of depleted uranium, lead, and steel were studied. The capacity of the casks was assumed to … more

Date: April 1, 1980

Creator: Sutherland, S.H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Release criteria and pathway analysis for radiological remediation

Site-specific activity concentrations were derived for soils contaminated with mixed fission products (MFP), or uranium-processing residues, using the Department of Energy (DOE) pathway analysis computer code RESRAD at four different sites. The concentrations and other radiological parameters, such as limits on background-subtracted gamma exposure rate were used as the basis to arrive at release criteria for two of the sites. Valid statistical parameters, calculated for the distribution of radi… more

Date: 1991

Creator: Subbaraman, G.; Tuttle, R. J.; Oliver, B. M. & Devgun, J. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Levels of radioactivity in fish from streams near F-Area and H-Area seepage basins

This report summarizes results of recent analyses of radioactivity in fish from SRS streams near the F-Area and H-Area seepage basins. Fish were collected from headwater areas of Four Mile Creek and Pen Branch, from just below the H-Area seepage basin, and from three sites downstream in Four Mile Creek. These fish were analyzed for gross alpha and gross beta radioactivity using standard EPA methods. Levels of gross alpha and nonvolatile beta radioactivity in fish were found to be comparable to … more

Date: May 1, 1991

Creator: Murphy, C. E. Jr. & Loehle, C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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When is a dose not a dose

Although an enormous amount of progress has been made in the fields of radiation protection and risk assessment, a number of significant problems remain. The one problem which transcends all the rest, and which has been subject to considerable misunderstanding, involves what has come to be known as the 'linear non-threshold hypothesis', or 'linear hypothesis'. Particularly troublesome has been the interpretation that any amount of radiation can cause an increase in the excess incidence of cance… more

Date: January 1, 1991

Creator: Bond, V.P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Alternate fuel cycle technologies. Quarterly report, April--June 1977

This quarterly report describes studies to provide information needed to close the back end of the commercial light-water reactor (LWR) fuel cycle. These efforts are directed primarily at reprocessing and recycle of uranium and plutonium from spent LWR fuel. Research is reported in the following categories: environmental studies, fuel receipt, head-end processes, purex process, waste management, safeguards (dose rate for extraction streams), and general support.

Date: September 1, 1977

Item Type: Report

Partner: UNT Libraries Government Documents Department

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A comparison of dose and dose-rate conversion factors from the Soviet Union, United Kingdom, US Department of Energy, and the Idaho National Engineering Laboratory Fusion Safety Program

Several independent data sets of radiological dose and dose-rate conversion factors (DCF/DRCF) have been tabulated or developed by the international community both for fission and fusion safety purposes. This report compares sets from the US Department of Energy, the Soviet Union, and the United Kingdom with those calculated by the Idaho National Engineering Laboratory Fusion Safety Program. The objectives were to identify trends and potential outlying values for specific radionuclides and cont… more

Date: December 1, 1991

Creator: Rood, A.S. & Abbott, M.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Gamma Exposure Rates Due to Neutron Activation of Soil: Site of Hood Detonation, Operation Plumbbob

This paper is the result of some recent discussions of exposure rates within the first few hours of the Hood detonation of the Plumbbob series due to neutron activation of soil. We estimated the exposure rates from 1/2 to 3 h after the detonation from ground zero to 1000 yards from ground zero. The area was assumed to be uncontaminated by fallout. Soil samples from the area of the Nevada Test Site at which the Hood device was detonated were sent to ORNL by Dr. John Malik of Los Alamos and by Mr… more

Date: June 1, 1980

Creator: Auxier, J. A. & Ohnesorge, W. F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Radiological survey of the inactive uranium-mill tailings at Ambrosia Lake, New Mexico

The inactive uranium-mill tailings pile at Ambrosia Lake, New Mexico, contains approximately 1520 Ci of /sup 226/Ra in 2.4 million metric tons of tailings covering an area of 43 hectares. All of the former mill buildings were intact and, at the time of this survey, several were in use. The tailings have not been stabilized, but the crusty surface is reported to be resistant to wind erosion. The average gamma-ray exposure rate 1 m above the tailings is 720 ..mu..R/h while the average rate in the… more

Date: June 1, 1980

Creator: Haywood, F. F.; Christian, D. J.; Ellis, B. S.; Hubbard Jr., H. M.; Lorenzo, D. & Shinpaugh, W. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Hanford Environmental Dose Reconstruction Project Monthly Report

The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Pacific Northwest Laboratory (PNL) under the direction of an independent Technical Steering Panel (TSP). The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impa… more

Date: July 1, 1991

Creator: Finch, S.M. (comp.)

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Hazards control progress report No. 58, April-September 1979

Progress is reported on research in the areas of radiation protection and industrial hygiene. Subject areas include: (1) basic computer programs for counting room automation; (2) a computing portable neutron spectrometer; (3) preliminary measurements of the neutron energy response of CR-39 carbonate plastic; (4) effect of high-expansion foam on self-1 contained breathing apparatuses; (5) permeation of organic solvents through glove samples; (6) determining neutron dose rates and 9-to-3 in. sphe… more

Date: February 22, 1980

Creator: Griffith, R.V. (ed.)

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Contaminant pathway analysis and health risk assessment of the Metallurgical Laboratory Basin

The specific objectives of this report are to present a technically detailed site description for the Metallurgical Laboratory basin, to document the manner in which it was modeled by the PATHRAE computer code, and to present the results of the pathway analyses, in terms of both contaminant transport and health risks. This will provide part of a detailed assessment of environmental risks and impacts from the Metallurgical Laboratory both in its present condition and after possible remedial acti… more

Date: December 1, 1985

Creator: Klein, R. B.; Merrell, G. B.; Nielson, K. K. & Rogers, V. C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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PHOTON: A program for synchrotron radiation dose calculations

A computer program, PHOTON, has been developed to calculate radiation levels associated with a general synchrotron beamline arrangement. PHOTON calculates the transmitted an scattered spectra as the synchrotron beam passes through sequential filters. The Compton component of this scattered radiation can then be passed through a series of materials composing a shielding wall. This radiation can then be used to calculate a dose in a medium outside of the shielding wall. Program input is such that… more

Date: January 1, 1987

Creator: Chapman, D.; Gmeur, N.; Lazarz, N. & Thomlinson, W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Genetic effects of low x-ray doses. Progress report, October 1, 1976--September 30, 1977. [In Drosophila]

A linear-quadratic model of dose-kinetics is proposed for x-ray induced recessive lethal mutations in oogonia of Drosophila. From this it should follow that at higher total doses fractionation treatments should give a lower yield of mutations than an equivalent acute exposure. A dose of 6000 R, given acutely and in 3 different fractionation regimes gave results in the expected direction for 2 x 3000 R, and a significant decrease for 3 x 2000 R and for 4 x 1500 R fractionations.

Date: September 1, 1977

Creator: Abrahamson, S. & Meyer, H.U.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Calculated concentrations of any radionuclide deposited on the ground by release from underground nuclear detonations, tests of nuclear rockets, and tests of nuclear ramjet engines

This report presents calculated gamma radiation exposure rates and ground deposition of related radionuclides resulting from three types of event that deposited detectable radioactivity outside the Nevada Test Site complex, namely, underground nuclear detonations, tests of nuclear rocket engines and tests of nuclear ramjet engines.

Date: November 1, 1981

Creator: Hicks, H.G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Delayed radiation injury of gut-exposed and gut-shielded mice. II. The decrement in life span

Two mouse strains (RF/J and C57B1/6J) were exposed to x-ray doses totaling 400, 800, and 1200 rad. Total doses were given in 200-rad fractions at 7-day intervals to the whole body, gut only, or bone tissue with the gut shielded. Animals were anesthetized during exposure. Two control groups were used. A sham control group was anesthetized but not exposed to x rays, and another control group received neither anesthesia nor x-radiation. All mice were retained in a standard laboratory environment f… more

Date: January 1, 1978

Creator: Spalding, J.F.; Archuleta, R.F. & Prine, J.R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Radiation Survey and Dosimeter Intercomparison Study at the Health Physics Research Reactor.

No Description Available.

Date: January 1, 1968

Creator: Kerr, G. D. & Johnson, D. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department