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Clonal theory of radiation carcinogenesis

Description: In some cases, usually involving high-LET radiations, the dose response at low doses follows a power function of dose with exponent less than one over a wide dose range. This type of response is of great interest since (a) it implies greater effect per unit dose at progressively smaller doses, and (b) it is not predicted by most models and theories of radiobiology. A theoretical framework is presented for responses having the above characteristics over a dose range extending over a factor of 10… more
Date: January 1, 1982
Creator: Baum, J.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Sensitivity of primary knock-on atom spectra and displacement per atom cross sections to different secondary neutron energy and angular distributions and ''in-group'' weighting schemes

Description: The sensitivity of primary knock-on atom (PKA) spectra and displacement per atom (DPA) cross sections to different secondary neutron energy and angular distributions and ''in-group'' weighting schemes is investigated. It is shown that the sensitivity of the PKA spectra and DPA cross sections for the (n,n' unresolved) and (n,2n) reactions in Fe to different angular distributions and the same secondary neutron spectrum is reasonably large (approximately 15%), whereas the … more
Date: January 1, 1978
Creator: Gabriel, T. A. & Bishop, B. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Background radiation from fission pulses

Description: Extensive source terms for beta, gamma, and neutrons following fission pulses are presented in various tabular and graphical forms. Neutron results from a wide range of fissioning nuclides (42) are examined and detailed information is provided for four fuels: /sup 235/U, /sup 238/U, /sup 232/Th, and /sup 239/Pu; these bracket the range of the delayed spectra. Results at several cooling (decay) times are presented. For ..beta../sup -/ and ..gamma.. spectra, only /sup 235/U and /sup 239/Pu result… more
Date: May 1, 1988
Creator: England, T. R.; Arthur, E. D.; Brady, M. C. & LaBauve, R. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Advanced Neutron Source

Description: The Advanced Neutron Source (ANS) is a new user experimental facility planned to be operational at Oak Ridge in the late 1990's. The centerpiece of the ANS will be a steady-state research reactor of unprecedented thermal neutron flux ({phi}{sub th} {approx} 9{center dot}10{sup 19} m{sup -2}{center dot}s{sup -1}) accompanied by extensive and comprehensive equipment and facilities for neutron-based research. 5 refs., 5 figs.
Date: January 1, 1989
Creator: Hayter, J. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radio chemistry as a diagnostic in laser fusion experiments

Description: Nuclear chemistry techniques have been employed in an attempt to measure the density of high compression laser fusion targets. Radioactive /sup 28/Al atoms formed in the /sup 28/Si(n,p)/sup 28/Al reaction arising from the interaction of the 14 MeV neutrons with the silicon atoms in the glass microsphere have been counted at Lawrence Livermore Laboratory using a ..beta..-..gamma.. coincidence method. The detection system that is employed allows activities corresponding to 100 aluminum atoms to b… more
Date: November 1, 1977
Creator: Campbell, E.M.; Hicks, H.G.; Mead, W.C.; Glaros, S.S.; Coleman, L.W. & Laird, W.B.
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Partner: UNT Libraries Government Documents Department
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Methods and techniques of NDA (nondestructive assay)

Description: Nondestructive assay (NDA) refers to techniques and instruments developed to measure nuclear materials in the many forms in which they occur throughout the fuel cycle. These techniques were first developed to support nuclear safeguards inspections and nuclear material accountability; they are also used extensively for process and quality control. Most accountability measurements are based on analytical chemistry and require that a sample be drawn and analyzed destructively. Destructive analysis… more
Date: January 1, 1988
Creator: Reilly, T. D.
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Partner: UNT Libraries Government Documents Department
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Health physics aspects of nuclear radiations from deuterium beam injectors

Description: Estimations are made for X-ray generation from the accelerator column of various neutral beam injectors. For the case of deuterium beam operation where 2.5-MeV D-D neutrons pose a serious health physics concern, neutron and tritium production rates from beam targets are calculated for different beam energies. Biological doses from these radiations and shielding requirements are discussed.
Date: February 1, 1978
Creator: Kim, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Soviet American Gallium Experiment (SAGE)

Description: A radiochemical experiment using the reaction v/sub e/ = /sup 71/Ga + e/sup e/ to determine the integral flux of low-energy neutrinos from the sun is currently under preparation at the Baksan Neutrino Observatory in the USSR. Measurements are scheduled to commence by late 1988 using /approximately/30 tonnes of metallic gallium. With this amount of gallium it should be possible to obtain a fractional statistical accuracy of 12 to 15% after one year (assuming the standard solar model neutrino flu… more
Date: January 1, 1988
Creator: Abazov, A. I.; Abdurashitov, D. N.; Anosov, O. P.; Avdeyev, A. V.; Belousko, Yu. I.; Bychuk, O. V. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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New newtron time-of-flight (NTOF) facilities at the Brookhaven 200-MeV Linac

Description: The installation of a new beam chopper and radio-frequency quadrupole (RFQ) preinjector (750 keV) at the Brookhaven National Laboratory (BNL) 200-MeV Linac will enable single micropulse selection (pulse width <1 ns) with periods ranging from 400 ns to 10 ..mu..s. The standard micropulse intensity is 1.2 X 10/sup 9/ p..mu.. pulse with dc-average beam currents of 50 nA-1 ..mu..A routinely available. The NTOF facilities consists of 30-100 meter flight paths at angles of 0, 12, 30, 45, 90, and 135/… more
Date: January 1, 1988
Creator: Ward, T.E.; Alessi, J.; Brennan, J.; Grand, P.; Lankshear, R.; Snead, C.L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiation standards and calibrations. FY-1981 annual report

Description: The research program encompasses: reviewing calibration standards, regulations, and handbooks; assuring that calibration procedures used are in agreement with technically accepted methods; maintaining basic radioactive sources and instruments that serve as radiological standards; and providing traceability to the National Bureau of Standards where possible. In addition, major efforts are being expended to upgrade the 318 calibration facility. This report focuses on major accomplishments during … more
Date: July 1, 1982
Creator: Roberson, P. L.; Yoder, R. C.; Fox, R. A.; Hooker, C. D.; Hogan, R. T.; Holbrook, K. L. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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NDA technology for uranium resource evaluation. Progress report July 1-December 31, 1979. [Gamma spectra calculations; field prototype photoneutron logging probe]

Description: This report describes work performed during the time period from July 1, 1979 to December 31, 1979, on the contract for Nondestructive Nuclear Analysis (NDA) Technology for Uranium Resource Evaluation in Group Q-1. Calculational effort was focused on improving the accuracy with which detector response function maps can be generated for subsequent enfolding with ONETRAN angular flux data. Experimental effort was highlighted by a field test of the prototype photoneutron logging probe at the Grand… more
Date: August 1, 1980
Creator: Evans, M.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Phonon dispersion relation of uranium nitrate above and below the Neel temperature

Description: Neutron coherent inelastic scattering measurements have been made of the phonon dispersion relation of uranium nitride both above and below the Neel temperature T/sub N/ = 50 K. Within the precision of the measurements, about 1% in frequency and 10% in line width and in scattered neutron intensity, no significant changes in these phonon properties were observed as a function of temperature other than those arising from population factor changes and a small stiffening of the lattice as the tempe… more
Date: January 1, 1977
Creator: Dolling, G; Holden, T M; Evensson, E C; Buyers, W J.L. & Lander, G H
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Absolute measurement of anti. nu. for /sup 252/Cf

Description: Neutron yields were determined by measuring the activities produced in the INEL manganese bath. Of the three fission methods used, the neutron-fission coincidence method was found to be the most consistent and reliable. The value of /sup 252/Cf anti ..nu.. obtained by these measurements was 3.764. (RWR)
Date: January 1, 1980
Creator: Smith, J. R.; Reeder, S. D. & Gehrke, R. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Material Considerations in the Design of a Bulk Shield for the Fusion Engineering Device

Description: The FED bulk shield provides protection from high-energy neutrons and gamma rays and removes nuclear heat generated. Bulk shield optimization calculations were conducted using the Los Alamos ONEDANT discrete ordinates and the General Atomic PATH point kernel codes. Six candidate steel alloys were considered.
Date: January 1, 1981
Creator: Kirchner, J. & Engholm, B. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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N and. delta. resonances: an experimental review

Description: Experimental progress in N and ..delta.. resonances since the Oxford baryon conference is reviewed. The review concentrates on hadronic channels, and on developments of the last one or two years. The topics reviewed include the antiproton lifetime; the ..delta../sup + +/ magnetic moment; measurements of ..pi..N elastic and charge-exchange scattering in the ..delta.. region, the eta n threshold region, and the high-mass region; partial wave analyses of ..pi..N ..-->.. ..pi..N; measurements of tw… more
Date: July 1, 1980
Creator: Kelly, R.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tests of parity and time reversal invariance in neutron-nucleus scattering

Description: I'll discuss the experiments in which parity violation has been measured in low energy neutron-nucleus scattering. The interest is two-fold: to understand how parity violation in the nucleon-nucleon (NN) interaction manifests itself in a complicated many-body system and to show that the large enhancements observed make this a good laboratory to search for violations of TRI. Further, the procedure of relating the measured parity violating asymmetries to the under-lying NN interaction will be imp… more
Date: January 1, 1989
Creator: Seestrom, S. J.; Bowman, C. D.; Bowman, J. D.; Knudson, J.; Mortensen, R.; Penttila, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of a neutron scattering and gamma-ray production integral and experiment on silicon dioxide for neutron energies from 1 to 15 MeV

Description: Monte Carlo calculations were made to analyze the results of an integral experiment with a sample of SiO/sub 2/ to determine the adequacy of ENDF/B-IV neutron scattering and gamma-ray production cross-section data for silicon and oxygen. The experimental results analyzed included energy-dependent NE-213 detector neutron and gamma-ray count rates at a scattering angle of 90 deg and pulse-height spectra for scattered neutrons and gamma rays. The experiments were carried out with the ORELA 1- to 2… more
Date: January 1, 1978
Creator: Cramer, S. N. & Oblow, E. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Passive neutron dosimetry on cruise missile tests

Description: One of the components exercised during development tests of cruise missiles is the neutron generator that supplies the burst of neutrons needed to initiate a nuclear explosion. The subject of this report is a method of verifying the production of neutrons using a passive neutron activation technique that is sufficiently sensitive to detect a decay rate of a few atoms per hour.
Date: January 1, 1980
Creator: Ewing, R.I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High-resolution neutron transmission measurements on /sup 235/U, /sup 239/Pu, and /sup 238/U

Description: High-resolution transmission measurements have been made on three sample thicknesses of both /sup 235/U and /sup 239/Pu at liquid nitrogen temperature and also on three of /sup 238/U at room temperature using neutrons from the water-moderated ORELA target. The data on /sup 235/U and /sup 239/Pu from 1 to 10,000 eV were obtained using /sup 6/Li glass scintillation detectors at 17.909-and 80.394-m flight paths. The /sup 238/U data from 1 to 100 keV were obtained using a new NE 110 proton-recoil s… more
Date: January 1, 1988
Creator: Harvey, J.A.; Hill, N.W.; Perey, F.G.; Tweed, G.L. & Leal, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Dosimetry measurements external to a 10 kiloliter liquid-air vessel containing a D-T neutron source. [14 MeV neutrons]

Description: To determine the radiation attenuation characteristics of liquid air (109 g/cm/sup 2/ thick) for 14 MeV neutrons from a central D-T source in a 10 kL vessel, radiation dose measurements were made using a large tissue-equivalent ion chamber external to the vessel. The shielding characteristics of steel spherical shells were also investigated. Experimental results were analyzed and compared with TARTNP Monte Carlo code calculations. Degradation of the ion chamber's response to high-energy neutron… more
Date: October 10, 1977
Creator: Tripler, D. J.; Goldberg, E. & Farley, W. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design studies of a laser fusion power plant

Description: The conceptual design of a laser fusion power plant has been undertaken to exploit recent developments in target design. Advanced high-gain targets which have been developed make it possible to significantly relax the laser and optical system requirements. The power plant design features a reactor concept which utilizes a thick falling region of liquid lithium to protect the first-wall from the neutrons, x-rays, and charged particles that are produced in the thermonuclear microexplosion. The li… more
Date: October 7, 1977
Creator: Maniscalco, J. A.; Meier, W. R. & Monsler, M. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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/sup 3/H(p,n)/sup 3/He differential cross sections below 5 MeV and the n-/sup 3/He cross sections. [2. 5 and 4. 0 MeV]

Description: Complete angular distributions for the /sup 3/H(p,n)/sup 3/He reaction were measured at 2.5 and 4.0 MeV with the /sup 1/H(t,n)/sup 3/He reaction used to obtain the backward yields. Because the distributions are peaked about 17% more strongly in the backward direction than the best previous elevation suggests (based on extrapolated data), the /sup 3/H(p,n)/sup 3/He reaction cross sections below 5 MeV were re-evaluated without the extrapolated data. The results were compared with recent total n-/… more
Date: July 1, 1980
Creator: Drosg, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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