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Selected etching and annealing properties of Brazilian quartz crystals for solid state track recorder applications

Description: The etching and annealing properties of Brazilian quartz crystals are under investigation to determine their suitability for use as solid state track recorders (SSTR) and damage monitors in nuclear reactor environments, where temperatures and neutron fluences are high. Observer objectivity in counting fission tracks has been established at the 1 to 2% level, and a method of standardizing chemical etching from one sample of quartz to another has been found. A method has also been found to make c… more
Date: January 1, 1981
Creator: Roberts, J.H.; Gold, R. & Ruddy, F.H.
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Partner: UNT Libraries Government Documents Department
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The next decade in external dosimetry

Description: As the radiation protection community moves through the last half of the '80s and into the next decade, we can expect the requirements for external dosimetry to become increasingly more restrictive and demanding. As in other health protection fields, growing regulatory and legal pressures, together with a natural evolution in philosophy, require the health physicist to display an increasing degree of accountability, rigor, and professionalism. The good news is that, for the most part, the techn… more
Date: October 1, 1986
Creator: Griffith, R. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Solid State Track Recorder applications in United States nuclear reactor energy programs

Description: The domain of Solid State Track Recorder (SSTR) applications in United States nuclear reactor energy programs extends from the harsh high temperature environments found in high power reactor cores to very low flux environments arising in out-of-core locations, critical assemblies, or away from reactors (AFR) experiments. The neutron energy region arising in these applications is very broad, covering more than eight orders of magnitude from thermal up to fusion energies. The range of neutron flu… more
Date: January 1, 1980
Creator: Gold, R.; Ruddy, F.H. & Roberts, J.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Energy Dependence of Fast Neutron Dosimetry Using Electrochemical Etching

Description: Registration of fast-neutron induced recoil tracks by the electrochemical etching technique as applied to sensitive Lexan polycarbonate foils provides a simple and inexpensive means of fast neutron personnel dosimetry. The sensitivity (tracks/neutron) of recoil particle registration is given as a function of neutron energy. Neutrons of < 4,3 MeV, 14 MeV, and 22 MeV were produced by the reactions /sup 7/Li (p,n) /sup 7/Be, /sup 3/T (d,n) /sup 4/He and /sup 9/B, respectively. Results are compared… more
Date: January 1, 1978
Creator: Su, S.J. & Morgan, K.Z.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Energy and Technology Review

Description: A specialized laser amplifier for use with velocity-measuring systems is described which makes possible detailed measurements of explosion-driven targets extending over long times. The experimental and diagnostic facilities of the Bunker 801 project enables sensitive and thorough hydrodynamics tests on the high-explosive components of nuclear devices. An improved spectrometry system has been developed covering the energy range from 0.025 eV to 20 MeV for use in radiation monitoring, and a new m… more
Date: February 1, 1986
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Proceedings of the workshop on new solid state devices for high energy physics. [LBL, October 28-30, 1985]

Description: This paper contains articles on semiconductor devices used in the detection of high energy particles. Some articles reported: Position sensitive semiconductor devices; Scintillation techniques and optical devices; Radiation damage to detectors; VLSI for physics; and experience with Si detectors in NA32. (LSP)
Date: December 1, 1987
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Applications of solid state track recorder neutron dosimetry for fuel debris location in the Three Mile Island Unit 2 reactor coolant system

Description: As a result of the Three Mile Island Unit (TMI-2) accident on March 28, 1979, fuel debris was dispersed into the primary coolant and auxilliary systems of the reactor. The presence of fuel may be traced by using the neutron activity which is associated with the burn-in of higher actinides (about 300 neutrons/sec/kgU). Solid state track recorder (SSTR) neutron dosimetry is the most sensitive technique for measuring low neutron fluxes. Hence, neutron dosimetry is being performed at TMI-2 to locat… more
Date: January 1, 1983
Creator: Ruddy, F.H.; Roberts, J.H.; Gold, R. & Preston, C.C.
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Partner: UNT Libraries Government Documents Department
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Imaging using accelerated heavy ions

Description: Several methods for imaging using accelerated heavy ion beams are being investigated at Lawrence Berkeley Laboratory. Using the HILAC (Heavy-Ion Linear Accelerator) as an injector, the Bevalac can accelerate fully stripped atomic nuclei from carbon (Z = 6) to krypton (Z = 34), and partly stripped ions up to uranium (Z = 92). Radiographic studies to date have been conducted with helium (from 184-inch cyclotron), carbon, oxygen, and neon beams. Useful ranges in tissue of 40 cm or more are availab… more
Date: May 1, 1982
Creator: Chu, W.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development and Application of the Electrochemical Etching Technique. Annual Progress Report

Description: This annual progress report documents further advances in the development and application of electrochemical etching of polycarbonate foils (ECEPF) for fast, intermediate, and thermal neutron dosimetry as well as alpha particle dosimetry. The fast (> 1.1 MeV) and thermal neutron dosimetry techniques were applied to a thorough investigation of the neutron contamination inherent in and about the primary x-ray beam of several medical therapy electron accelerators. Because of the small size of ECEP… more
Date: August 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Silicon-based elementary particle tracking system: Materials science and mechanical engineering design

Description: Research and development of the mechanical, cooling, and structural design aspects of a silicon detector-based elementary particle tracking system has been performed. Achieving stringent system precision, stability, and mass requirements necessitated the use of graphite fiber-reinforced cyanate-ester (C-E) resins. Mechanical test results of the effects of butane, ionizing radiation, and a combination of both on the mechanical properties of these materials are presented, as well as progress on d… more
Date: January 1, 1993
Creator: Miller, W. O.; Gamble, M. T.; Thompson, T. C. & Hanlon, J. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Long-range fission fragments from radiogenic lead. [Fission of nuclides with Z approx = 114]

Description: Fission tracks with a range 19 percent longer than tracks produced by uranium fission fragments were observed on mylar foils after a three-year underground (100 m.w.e.) exposure to 3600 cm/sup 2/ of radiogenic lead. Ordinary lead which was simultaneously exposed to mylar foils under the same conditions yielded a background effect of only 3 percent of the effect from radiogenic lead. The observed long-range tracks are best explained as resulting from the spontaneous fission of natural, superheav… more
Date: June 1, 1978
Creator: Maly, J. & Walz, D.R
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cabling for an SSC silicon tracking system

Description: As part of the Superconducting Super Collider Laboratory (SSCL) funded silicon tracking subsystem R D program, we examine the problems associated with cabling such a system. Different options for the cabling plant are discussed. A silicon microstrip tracking detector for an SSC experiment is an extremely complex system. The system consists of approximately 10{sup 7} detector channels, each of which requires a communication link with the outside world and connections to the detector bias voltage… more
Date: January 1, 1990
Creator: Ziock, H.; Boissevain, J.; Cooke, B. & Miller, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Combination TLD/TED dose assessment

Description: During the early 1980s, an appraisal of dosimetry programs at US Department of Energy (DOE) facilities identified a significant weakness in dose assessment in fast neutron environments. Basing neutron dose equivalent on thermoluminescence dosimeters (TLDS) was not entirely satisfactory for environments that had not been well characterized. In most operational situations, the dosimeters overrespond to neutrons, and this overresponse could be further exaggerated with changes in the neutron qualit… more
Date: November 1, 1992
Creator: Parkhurst, M.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High energy collisions of nuclei: experiments

Description: Heavy-ion nuclear reactions with projectile energies up to 2.1 GeV/A are reviewed. The concept of ''rapidity'' is elucidated, and the reactions discussed are divided into sections dealing with target fragmentation, projectile fragmentation, and the intermediate region, with emphasis on the production of light nuclei in high-energy heavy-ion collisions. Target fragmentation experiments using nuclear emulsion and AgCl visual track detectors are also summarized. 18 figures. (RWR)
Date: September 1, 1977
Creator: Heckman, H.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Comparative evaluation of radon measurement techniques for uranium exploration. National Uranium Resource Evaluation

Description: The measurement of radon (Rn-222) in soil gas aids in uranium exploration by indicating indirectly the presence of buried ore bodies. Intrest in this exploration methodology has led to the development of various radon measurement techniques which detect the presence of soil-gas radon, both directly and/or indirectly. To establish the relative merit of these new radon measurement techniques, Bendix Field Engineering Corporation has tested a variety of them using existing uranium occurrences loca… more
Date: March 1, 1983
Creator: Czarnecki, R F; Pacer, J C & Freeman, R W
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Personnel dosimetry intercomparison studies at the ORNL Health Physics Research Reactor

Description: The Health Physics Research Reactor (HPRR), used unshielded, with a 12-cm-thick Lucite shield or a 13-cm-thick steel shield, provided three neutron and gamma-ray spectra for personnel dosimetry intercomparison studies. The characterisitcs of these fields, such as neutron energy spectrum, intensity, and uniformity, had been measured previously during nuclear accident dosimetry studies. Exposures were made to simulate total exposures likely to be encountered in personnel dosimetry. Neutron dose e… more
Date: January 1, 1977
Creator: Dickson, H.W. & Gilley, L.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Twelve years of neutron personnel dosimetry intercomparison studies at Oak Ridge National Laboratory: What have we learned

Description: To provide an opportunity for dosimetrists to test and calibrate their personnel neutron monitoring systems in a variety of incident radiation fields, the staff of the Dosimetry Applications Research (DOSAR) Facility at the Oak Ridge National Laboratory (ORNL) has conducted personnel dosimetry intercomparison studies (PDIS) periodically since 1974 and annually since 1976 (Si82, Sw87). During these studies, personnel dosimeters are mailed to ORNL, mounted on phantoms and exposed to low-level (le… more
Date: January 1, 1988
Creator: Swaja, R. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Adapting the Polycarbonate Dosimeter and Electrochemical Etching to the Microdosimetry of /sup 239/Pu in Bone

Description: The problem of setting the maximum permissible body burden, MPBB, for /sup 239/Pu is a complex one. Recent papers have been published which favor lowering the MPBB by varying factors depending on the assumptions used. /sup 239/Pu has been shown quite clearly, on detailed autoradiograph, to concentrate on the trabecular surfaces of the endosteal face of osseous tissue. This realization led the ICRP to propose the alteration of the MPBB for /sup 239/Pu in a manner based upon microdosimetry of /su… more
Date: January 1, 1977
Creator: Stillwagon, G.B.; Su, S.J. & Morgan, K.Z.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cellulose acetobutyrate films and beryllium oxide discs for low-level radiation monitoring

Description: The effect of mylar films on the attenuation of alpha particle energy and the production of etchable tracks in cellulose acetobutyrate was studied. A model developed predicts a 15-..mu.. optimum mylar film thickness, while experimental results indicated a 22.8-..mu.. optimum. The effect of alpha particle and potassium hydroxide solution interaction with CAB was reviewed and process improvements suggested. The TSEE response of BeO discs to tritium at 5.0 mCi/m/sup 3/ for up to 15-hr exposure was… more
Date: October 1, 1976
Creator: Ventura, S. A.; Kleinschmidt, D. E. & Mbu, J. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of experiences in long-term radon and radon-daughter measurements

Description: Pacific Northwest Laboratory (PNL) is performing side-by-side measurements of radon and radon daughter concentrations using several instruments and techniques, and is comparing these measurements with side-by-side measurements made by other investigators at other locations. The standard deviation of the differences between the (natural) logarithms of the Terradex Track Etch radon concentrations and the logarithms of the Radon Progency Integrating Sampling Units (RPISU) radon daughter concentrat… more
Date: December 1, 1982
Creator: Young, J. A.; Jackson, P. O. & Thomas, V. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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