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Sample records for nuclear radiation

  1. Nuclear radiation actuated valve

    DOEpatents

    Christiansen, David W.; Schively, Dixon P.

    1985-01-01

    A nuclear radiation actuated valve for a nuclear reactor. The valve has a valve first part (such as a valve rod with piston) and a valve second part (such as a valve tube surrounding the valve rod, with the valve tube having side slots surrounding the piston). Both valve parts have known nuclear radiation swelling characteristics. The valve's first part is positioned to receive nuclear radiation from the nuclear reactor's fuel region. The valve's second part is positioned so that its nuclear radiation induced swelling is different from that of the valve's first part. The valve's second part also is positioned so that the valve's first and second parts create a valve orifice which changes in size due to the different nuclear radiation caused swelling of the valve's first part compared to the valve's second part. The valve may be used in a nuclear reactor's core coolant system.

  2. Nuclear Radiation Damages Minds!

    ERIC Educational Resources Information Center

    Blai, Boris, Jr.

    Professors Ernest Sternglass (University of Pittsburgh) and Steven Bell (Berry College) have assembled cogent, conclusive evidence indicating that nuclear radiation is associated with impaired cognition. They suggest that Scholastic Aptitude Scores (SATs), which have declined steadily for 19 years, will begin to rise. Their prediction is based on…

  3. Nuclear Radiation and the Thyroid

    MedlinePlus

    ... most radiation-sensitive parts of the body. Most nuclear accidents release radioactive iodine into the atmosphere which can ... works? After the 1986 Chornobyl (formerly called “Chernobyl”) nuclear accident, shifting winds blew a radioactive cloud over Europe. ...

  4. RADIATION FACILITY FOR NUCLEAR REACTORS

    DOEpatents

    Currier, E.L. Jr.; Nicklas, J.H.

    1961-12-12

    A radiation facility is designed for irradiating samples in close proximity to the core of a nuclear reactor. The facility comprises essentially a tubular member extending through the biological shield of the reactor and containing a manipulatable rod having the sample carrier at its inner end, the carrier being longitudinally movable from a position in close proximity to the reactor core to a position between the inner and outer faces of the shield. Shield plugs are provided within the tubular member to prevent direct radiation from the core emanating therethrough. In this device, samples may be inserted or removed during normal operation of the reactor without exposing personnel to direct radiation from the reactor core. A storage chamber is also provided within the radiation facility to contain an irradiated sample during the period of time required to reduce the radioactivity enough to permit removal of the sample for external handling. (AEC)

  5. [Potential radiation hazard in nuclear medicine].

    PubMed

    Guilabert, Nadine; Ricard, Marcel; Chamoulaud, Karen; Mazelier, Carole; Schlumberger, Martin

    2015-01-01

    Nuclear medicine uses unsealed radioisotopes. The potential radiation hazards depend on the amount of radioactivity administered and the type of radionucleide. Thus, radiation safety instructions will minimize radiation exposure and contamination as low as reasonably achievable. National nuclear safety authority requires rules, regulations and exposure limits for both patients and workers. Good practices and training staff contribute to optimize the radioprotection. PMID:25842441

  6. Nuclear Technology Series. Course 19: Radiation Shielding.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

  7. Nuclear Technology Series. Course l: Radiation Physics.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

  8. Radiation Effects in Nuclear Waste Materials

    SciTech Connect

    William j. Weber; Lumin Wang; Jonathan Icenhower

    2004-07-09

    The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics, which may impact the performance of nuclear waste forms and stabilized nuclear materials.

  9. Nuclear radiation cleanup and uranium prospecting

    DOEpatents

    Mariella, Jr., Raymond P.; Dardenne, Yves M.

    2016-02-02

    Apparatus, systems, and methods for nuclear radiation cleanup and uranium prospecting include the steps of identifying an area; collecting samples; sample preparation; identification, assay, and analysis; and relating the samples to the area.

  10. Radiation hardening design of nuclear powered spacecraft

    NASA Technical Reports Server (NTRS)

    Schmidt, R. E.

    1987-01-01

    The design and operation of space systems utilizing nuclear fueled power systems must consider the radiation environment from the earliest stages of their design. A range of nuclear systems are being considered for present and future satellite systems capable of supplying tens of kilowatts to multimegawatt and generating a corresponding range of radiation environments. The effects of these radiations on electronics and materials can be minimized by implementing early design considerations which maximize the design efficiency and minimize the impact on system mass. Space systems design considerations for the radiation environment must include all sources in addition to the self induced gamma ray and neutron radiation. These include the orbital dependent environment from the high energy electron and protons encountered in natural space. The system trades which the designer must consider in the development of space platforms which utilize nuclear reactor power supplies are discussed.

  11. Non-equilibrium radiation nuclear reactor

    NASA Technical Reports Server (NTRS)

    Thom, K.; Schneider, R. T. (Inventor)

    1978-01-01

    An externally moderated thermal nuclear reactor is disclosed which is designed to provide output power in the form of electromagnetic radiation. The reactor is a gaseous fueled nuclear cavity reactor device which can operate over wide ranges of temperature and pressure, and which includes the capability of processing and recycling waste products such as long-lived transuranium actinides. The primary output of the device may be in the form of coherent radiation, so that the reactor may be utilized as a self-critical nuclear pumped laser.

  12. [Nuclear News -- Isotopes and Radiation

    SciTech Connect

    Sinco, P.

    1999-11-01

    The topics discussed in this section are: (1) FDG--a significant development in nuclear medicine; (2) Contamination at Paducah plant prompts actions and reactions; and (3) Drug relieves side effects of cancer therapies in mice.

  13. Radiation chemistry for modern nuclear energy development

    NASA Astrophysics Data System (ADS)

    Chmielewski, Andrzej G.; Szołucha, Monika M.

    2016-07-01

    Radiation chemistry plays a significant role in modern nuclear energy development. Pioneering research in nuclear science, for example the development of generation IV nuclear reactors, cannot be pursued without chemical solutions. Present issues related to light water reactors concern radiolysis of water in the primary circuit; long-term storage of spent nuclear fuel; radiation effects on cables and wire insulation, and on ion exchangers used for water purification; as well as the procedures of radioactive waste reprocessing and storage. Radiation effects on materials and enhanced corrosion are crucial in current (II/III/III+) and future (IV) generation reactors, and in waste management, deep geological disposal and spent fuel reprocessing. The new generation of reactors (III+ and IV) impose new challenges for radiation chemists due to their new conditions of operation and the usage of new types of coolant. In the case of the supercritical water-cooled reactor (SCWR), water chemistry control may be the key factor in preventing corrosion of reactor structural materials. This paper mainly focuses on radiation effects on long-term performance and safety in the development of nuclear power plants.

  14. Radiation Effects in Nuclear Waste Materials

    SciTech Connect

    Weber, William J.; Corrales, L. Rene; Ness, Nancy J.; Williford, Ralph E.; Heinisch, Howard L.; Thevuthasan, Suntharampillai; Icenhower, Jonathan P.; McGrail, B. Peter; Devanathan, Ramaswami; Van Ginhoven, Renee M.; Song, Jakyoung; Park, Byeongwon; Jiang, Weilin; Begg, Bruce D.; Birtcher, R. B.; Chen, X.; Conradson, Steven D.

    2000-10-02

    Radiation effects from the decay of radionuclides may impact the long-term performance and stability of nuclear waste forms and stabilized nuclear materials. In an effort to address these concerns, the objective of this project was the development of fundamental understanding of radiation effects in glasses and ceramics, particularly on solid-state radiation effects and their influence on aqueous dissolution kinetics. This study has employed experimental, theoretical and computer simulation methods to obtain new results and insights into radiation damage processes and to initiate the development of predictive models. Consequently, the research that has been performed under this project has significant implications for the High-Level Waste and Nuclear Materials focus areas within the current DOE/EM mission. In the High-Level Waste (HLW) focus area, the results of this research could lead to improvements in the understanding of radiation-induced degradation mechanisms and their effects on dissolution kinetics, as well as development of predictive models for waste form performance. In the Nuclear Materials focus area, the results of this research could lead to improvements in the understanding of radiation effects on the chemical and structural properties of materials for the stabilization and long-term storage of plutonium, highly-enriched uranium, and other actinides. Ultimately, this research could result in improved glass and ceramic materials for the stabilization and immobilization of high-level tank waste, plutonium residues and scraps, surplus weapons plutonium, highly-enriched uranium, other actinides, and other radioactive materials.

  15. Initial radiations from tactical nuclear weapons

    SciTech Connect

    Loewe, W.E.

    1985-08-01

    Neutron and gamma-ray free-field kermas and fluence spectra for ranges between 1 and 2 km are presented for three tactical nuclear weapons and are compared with nuclear radiations at Hiroshima. The three tactical weapons are modeled as near-surface bursts of a fusion explosive, a fission explosive, and a suppressed-neutron explosive represented by the Little Boy bomb used at Hiroshima.

  16. Nuclear radiation analysis for TFTR

    SciTech Connect

    Ku, L.P.

    1980-09-01

    A multi-dimensional analysis of the radiation problems was performed for TFTR using the system established at PPPL. Simple, clean geometries were first used to establish the expected reference level. Different calculational models were compared. The characteristics of streaming and activation were then studied. It is shown that the objectives set forth for the TFTR shielding design are not entirely satisfied, based on our calculation. Using the results of this study as a baseline, a review of the shielding for TFTR and its upgrade, TFM, has been initiated with the objective of a shielding design modified to satisfy both modes of operation.

  17. Radiation Shielding for Nuclear Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    Caffrey, Jarvis A.

    2016-01-01

    Design and analysis of radiation shielding for nuclear thermal propulsion has continued at Marshall Space Flight Center. A set of optimization tools are in development, and strategies for shielding optimization will be discussed. Considerations for the concurrent design of internal and external shielding are likely required for a mass optimal shield design. The task of reducing radiation dose to crew from a nuclear engine is considered to be less challenging than the task of thermal mitigation for cryogenic propellant, especially considering the likely implementation of additional crew shielding for protection from solar particles and cosmic rays. Further consideration is thus made for the thermal effects of radiation absorption in cryogenic propellant. Materials challenges and possible methods of manufacturing are also discussed.

  18. Development of Curricula for Nuclear Radiation Protection, Nuclear Instrumentation, and Nuclear Materials Processing Technologies. Final Report.

    ERIC Educational Resources Information Center

    Hull, Daniel M.

    A study was conducted to assist two-year postsecondary educational institutions in providing technical specialty courses for preparing nuclear technicians. As a result of project activities, curricula have been developed for five categories of nuclear technicians and operators: (1) radiation protection technician, (2) nuclear instrumentation and…

  19. Covariance Spectroscopy Applied to Nuclear Radiation Detection

    SciTech Connect

    Trainham, R., Tinsley, J., Keegan, R., Quam, W.

    2011-09-01

    Covariance spectroscopy is a method of processing second order moments of data to obtain information that is usually absent from average spectra. In nuclear radiation detection it represents a generalization of nuclear coincidence techniques. Correlations and fluctuations in data encode valuable information about radiation sources, transport media, and detection systems. Gaining access to the extra information can help to untangle complicated spectra, uncover overlapping peaks, accelerate source identification, and even sense directionality. Correlations existing at the source level are particularly valuable since many radioactive isotopes emit correlated gammas and neutrons. Correlations also arise from interactions within detector systems, and from scattering in the environment. In particular, correlations from Compton scattering and pair production within a detector array can be usefully exploited in scenarios where direct measurement of source correlations would be unfeasible. We present a covariance analysis of a few experimental data sets to illustrate the utility of the concept.

  20. Nuclear dynamical diffraction using synchrotron radiation

    SciTech Connect

    Brown, D.E.

    1993-05-01

    The scattering of synchrotron radiation by nuclei is extensively explored in this thesis. From the multipole electric field expansion resulting from time-dependent nonrelativistic perturbation theory, a dynamical scattering theory is constructed. This theory is shown, in the many particle limit, to be equivalent to the semi-classical approach where a quantum mechanical scattering amplitude is used in the Maxwell inhomogeneous wave equation. The Moessbauer specimen whose low-lying energy levels were probed is a ferromagnetic lattice of {sup 57}Fe embedded in a yttrium iron garnet (YIG) crystal matrix. The hyperfine fields in YIG thin films were studied at low and room temperature using time-resolved quantum beat spectroscopy. Nuclear hyperfine structure quantum beats were measured using a fast plastic scintillator coincidence photodetector and associated electronics having a time resolution of 2.5 nsec. The variation of the quantum beat patterns near the Bragg [0 0 2] diffraction peak gave a Lamb-Moessbauer factor of 8.2{plus_minus}0.4. Exploring characteristic dynamical features in the higher order YIG [0 0 10] reflection revealed that one of the YIG crystals had bifurcated into two different layers. The dynamics of nuclear superradiance was explored. This phenomenon includes the radiative speedup exhibited by a collective state of particles, and, in striking concurrence, resonance frequency shifts. A speedup of a factor of 4 in the total decay rate and a beat frequency shift of 1{1/2} natural resonance linewidths were observed. Nuclear resonance scattering was also found to be a useful way of performing angular interferometry experiments, and it was used to observe the phase shift of a rotated quantum state. On the whole, nuclear dynamical diffraction theory has superbly explained many of the fascinating features of resonant magnetic dipole radiation scattered by a lattice of nuclei.

  1. Recoilless Nuclear Resonance Absorption of Gamma Radiation

    NASA Astrophysics Data System (ADS)

    Mössbauer, Rudolf L.

    It is a high distinction to be permitted to address you on the subject of recoilless nuclear resonance absorption of gamma radiation. The methods used in this special branch of experimental physics have recently found acceptance in many areas of science. I take the liberty to confine myself essentially to the work which I was able to carry out in the years 1955-1958 at the Max Planck Institute in Heidelberg, and which finally led to establishment of the field of recoilless nuclear resonance absorption. Many investigators shared in the preparations of the basis for the research we are concerned with in this lecture. As early as the middle of the last century Stokes observed, in the case of fluorite, the phenomenon now known as fluorescence - namely, that solids, liquids, and gases under certain conditions partially absorb incident electromagnetic radiation which immediately is reradiated. A special case is the so-called resonance fluorescence, a phenomenon in which the re-emitted and the incident radiation both are of the same wavelength. The resonance fluorescence of the yellow D lines of sodium in sodium vapour is a particularly notable and exhaustively studied example. In this optical type of resonance fluorescence, light sources are used in which the atoms undergo transitions from excited states to their ground states (Fig. 1.1). The light quanta emitted in these transitions (A → B) are used to initiate the inverse process of resonance absorption in the atoms of an absorber which are identical with the radiating atoms. The atoms of the absorber undergo a transition here from the ground state (B) to the excited state (A), from which they again return to the ground state, after a certain time delay, by emission of fluorescent light.

  2. Summary of Prometheus Radiation Shielding Nuclear Design Analysis

    SciTech Connect

    J. Stephens

    2006-01-13

    This report transmits a summary of radiation shielding nuclear design studies performed to support the Prometheus project. Together, the enclosures and references associated with this document describe NRPCT (KAPL & Bettis) shielding nuclear design analyses done for the project.

  3. Global nuclear radiation monitoring using plants

    NASA Astrophysics Data System (ADS)

    Islam, Mohammad; Romero-Talamas, Carlos; Kostov, Dan; Wang, Wanpeng; Liu, Zhongchi; Hussey, Daniel S.; Baltic, Eli; Jacobson, David L.; Gu, Jerry; Choa, Fow-Sen

    2005-05-01

    Plants exhibit complex responses to changes in environmental conditions such as radiant heat flux, water quality, airborne pollutants, soil contents. We seek to utilize the natural chemical and electrophysiological response of plants to develop novel plant-based sensor networks. Our present work focuses on plant responses to high-energy radiation - with the goal of monitoring natural plant responses for use as benchmarks for detection and dosimetry. For our study, we selected a plants cactus, Arabidopsis, Dwarf mango (pine), Euymus and Azela. We demonstrated that the ratio of Chlorophyll a to Chlorophyll b of the leaves has changed due to the exposure gradually come back to the normal stage after the radiation die. We used blue laser-induced blue fluorescence-emission spectra to characterize the pigment status of the trees. Upon blue laser excitation (400 nm) leaves show a fluorescence emission in the red spectral region between 650 and 800nm (chlorophyll fluorescence with maxima near 690nm and 735 nm). Sample tree subjects were placed at a distance of 1m from NIST-certified 241AmBe neutron source (30 mCi), capable of producing a neutron field of about 13 mrem/h. This corresponds to an actual absorbed dose of ~ 1 mrad/h. Our results shows that all plants are sensitive to nuclear radiation and some take longer time to recover and take less. We can use their characteristics to do differential detection and extract nuclear activity information out of measurement results avoid false alarms produced environmental changes. Certainly the ultimate verification can be obtained from genetic information, which only need to be done when we have seen noticeable changes on plant optical spectra, mechanical strength and electrical characteristics.

  4. Nuclear Technology Series. Course 20: Radiation Monitoring Techniques (Radiochemical).

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

  5. Nuclear Technology Series. Course 2: Radiation Protection I.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

  6. Nuclear Technology Series. Course 17: Radiation Protection II.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

  7. Nuclear Technology Series. Course 11: Radiation Detection and Measurement.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

  8. Regulation of nuclear radiation exposures in India.

    PubMed

    Mishra, U C

    2004-01-01

    India has a long-term program of wide spread applications of nuclear radiations and radioactive sources for peaceful applications in medicine, industry, agriculture and research and is already having several thousand places in the country where such sources are being routinely used. These places are mostly outside the Department of Atomic Energy (DAE) installations. DAE supplies such sources. The most important application of nuclear energy in DAE is in electricity generation through nuclear power plants. Fourteen such plants are operating and many new plants are at various stages of construction. In view of the above mentioned wide spread applications, Indian parliament through an Act, called Atomic Energy Act, 1964 created an autonomous body called Atomic Energy Regulatory Board (AERB) with comprehensive authority and powers. This Board issues codes, guides, manuals, etc., to regulate such installations so as to ensure safe use of such sources and personnel engaged in such installations and environment receives radiation exposures within the upper bounds prescribed by them. Periodic reports are submitted to AERB to demonstrate compliance of its directives. Health, Safety and Environment Group of Bhabha Atomic Research Centres, Mumbai carries out necessary surveillance and monitoring of all installations of the DAE on a routine basis and also periodic inspections of other installations using radiation sources. Some of the nuclear fuel cycle plants like nuclear power plants and fuel reprocessing involve large radioactive source inventories and have potential of accidental release of radioactivity into the environment, an Environmental Surveillance Laboratory (ESL) is set up at each such site much before the facility goes into operation. These ESL's collect baseline data and monitor the environment throughout the life of the facilities including the decommissioning stage. The data is provided to AERB and is available to members of the public. In addition, a multi

  9. Nuclear Cross Sections for Space Radiation Applications

    NASA Technical Reports Server (NTRS)

    Werneth, C. M.; Maung, K. M.; Ford, W. P.; Norbury, J. W.; Vera, M. D.

    2015-01-01

    The eikonal, partial wave (PW) Lippmann-Schwinger, and three-dimensional Lippmann-Schwinger (LS3D) methods are compared for nuclear reactions that are relevant for space radiation applications. Numerical convergence of the eikonal method is readily achieved when exact formulas of the optical potential are used for light nuclei (A = 16) and the momentum-space optical potential is used for heavier nuclei. The PW solution method is known to be numerically unstable for systems that require a large number of partial waves, and, as a result, the LS3D method is employed. The effect of relativistic kinematics is studied with the PW and LS3D methods and is compared to eikonal results. It is recommended that the LS3D method be used for high energy nucleon-nucleus reactions and nucleus-nucleus reactions at all energies because of its rapid numerical convergence and stability for both non-relativistic and relativistic kinematics.

  10. Radiation accidents and nuclear energy: medical consequences and therapy.

    PubMed

    Champlin, R E; Kastenberg, W E; Gale, R P

    1988-11-01

    After the accidents at Chernobyl, the Soviet Union, and in Goiania, Brazil, there is increasing concern about the medical risks from radiation accidents. This overview summarizes the principles of nuclear energy, the biologic effects of accidental radiation exposure, the emergency response to nuclear accidents, and approaches to treating radiation injuries. Also discussed are the related issues of reactor safety, the disposal of radioactive waste, and the proliferation of nuclear weapons. With the increasing use of radioactive materials for power, weapons, and medical diagnostics, the medical community needs to understand the health consequences of radiation exposure. PMID:3056171

  11. Review of radiation effects in solid-nuclear-waste forms

    SciTech Connect

    Weber, W.J.

    1981-09-01

    Radiation effects on the stability of high-level nuclear waste (HLW) forms are an important consideration in the development of technology to immobilize high-level radioactive waste because such effects may significantly affect the containment of the radioactive waste. Since the required containment times are long (10/sup 3/ to 10/sup 6/ years), an understanding of the long-term cumulative effects of radiation damage on the waste forms is essential. Radiation damage of nuclear waste forms can result in changes in volume, leach rate, stored energy, structure/microstructure, and mechanical properties. Any one or combination of these changes might significantly affect the long-term stability of the nuclear waste forms. This report defines the general radiation damage problem in nuclear waste forms, describes the simulation techniques currently available for accelerated testing of nuclear waste forms, and reviews the available data on radiation effects in both glass and ceramic (primarily crystalline) waste forms. 76 references.

  12. Effects of Nuclear Interactions in Space Radiation Transport

    NASA Technical Reports Server (NTRS)

    Lin, Zi-Wei; Barghouty, A. F.

    2004-01-01

    Space radiation transport codes have been developed to calculate radiation effects behind materials in human missions to the Moon, Mars or beyond. We study how nuclear fragmentation processes affect predictions from such radiation transport codes. In particular, we investigate the effects of fragmentation cross sections at different energies on fluxes, dose and dose-equivalent from galactic cosmic rays behind typical shielding materials.

  13. Effects of Nuclear Interactions in Space Radiation Transport

    NASA Technical Reports Server (NTRS)

    Lin, Zi-Wei; Barghouty, A. F.

    2005-01-01

    Space radiation transport codes have been developed to calculate radiation effects behind materials in human mission to the Moon, Mars or beyond. We study how nuclear fragmentation processes affect predictions from such radiation transport codes. In particular, we investigate the effects of fragmentation cross sections at different energies on fluxes, dose and dose-equivalent from galactic cosmic rays behind typical shielding materials.

  14. Radiation safety audit of a high volume Nuclear Medicine Department

    PubMed Central

    Jha, Ashish Kumar; Singh, Abhijith Mohan; Shetye, Bhakti; Shah, Sneha; Agrawal, Archi; Purandare, Nilendu Chandrakant; Monteiro, Priya; Rangarajan, Venkatesh

    2014-01-01

    Introduction: Professional radiation exposure cannot be avoided in nuclear medicine practices. It can only be minimized up to some extent by implementing good work practices. Aim and Objectives: The aim of our study was to audit the professional radiation exposure and exposure rate of radiation worker working in and around Department of nuclear medicine and molecular imaging, Tata Memorial Hospital. Materials and Methods: We calculated the total number of nuclear medicine and positron emission tomography/computed tomography (PET/CT) procedures performed in our department and the radiation exposure to the radiation professionals from year 2009 to 2012. Results: We performed an average of 6478 PET/CT scans and 3856 nuclear medicine scans/year from January 2009 to December 2012. The average annual whole body radiation exposure to nuclear medicine physician, technologist and nursing staff are 1.74 mSv, 2.93 mSv and 4.03 mSv respectively. Conclusion: Efficient management and deployment of personnel is of utmost importance to optimize radiation exposure in a high volume nuclear medicine setup in order to work without anxiety of high radiation exposure. PMID:25400361

  15. Radiation and transmutation effects relevant to solid nuclear waste forms

    SciTech Connect

    Vance, E.R.; Roy, R.; Pillay, K.K.S.

    1981-03-15

    Radiation effects in insulating solids are discussed in a general way as an introduction to the quite sparse published work on radiation effects in candidate nuclear waste forms other than glasses. Likely effects of transmutation in crystals and the chemical mitigation strategy are discussed. It seems probable that radiation effects in solidified HLW will not be serious if the actinides can be wholly incorporated in such radiation-resistant phases as monazite or uraninite.

  16. Lanthanum halide nanoparticle scintillators for nuclear radiation detection

    SciTech Connect

    Guss, Paul; Guise, Ronald; Yuan, Ding; Mukhopadhyay, Sanjoy; O'Brien, Robert; Lowe, Daniel; Kang, Zhitao; Menkara, Hisham; Nagarkar, Vivek V.

    2013-01-01

    Nanoparticles with sizes <10 nm were fabricated and characterized for their nanocomposite radiation detector properties. This work investigated the properties of several nanostructured radiation scintillators, in order to determine the viability of using scintillators employing nanostructured lanthanum tribromide, lanthanum trifluoride, or cerium tribromide. Preliminary results of this investigation are consistent with the idea that these materials have an intrinsic response to nuclear radiation that may be correlated to the energy of the incident radiation.

  17. Lanthanum halide nanoparticle scintillators for nuclear radiation detection

    SciTech Connect

    Guss, Paul; Guise, Ronald; O'Brien, Robert; Lowe, Daniel; Kang Zhitao; Menkara, Hisham; Nagarkar, Vivek V.

    2013-02-14

    Nanoparticles with sizes <10 nm were fabricated and characterized for their nanocomposite radiation detector properties. This work investigated the properties of several nanostructured radiation scintillators, in order to determine the viability of using scintillators employing nanostructured lanthanum trifluoride. Preliminary results of this investigation are consistent with the idea that these materials have an intrinsic response to nuclear radiation that may be correlated to the energy of the incident radiation.

  18. Satellite observation of atmospheric nuclear gamma radiation.

    PubMed

    Letaw, J R; Share, G H; Kinzer, R L; Silberberg, R; Chupp, E L; Forrest, D J; Rieger, E

    1989-02-01

    We present a satellite observation of the spectrum of gamma radiation from the Earth's atmosphere in the energy interval from 300 keV to 8.5 MeV. The data were accumulated by the gamma ray spectrometer on the Solar Maximum Mission over 3 1/2 years, from 1980 to 1983. The excellent statistical accuracy of the data allows 20 atmospheric line features to be identified. The features are superimposed on a continuum background which is modeled using a power law with index -1.16. Many of these features contain a blend of more than one nuclear line. All of these lines (with the exception of the 511-keV annihilation line) are Doppler broadened. Line energies and intensities are consistent with production by secondary neutrons interacting with atmospheric 14N and 16O. Although we find no evidence for other production mechanisms, we cannot rule out significant contributions from direct excitation or spallation by primary cosmic ray protons. The relative intensities of the observed line features are in fair agreement with theoretical models; however, existing models are limited by the availability of neutron cross sections, especially at high energies. The intensity and spectrum of photons at energies below the 511-keV line, in excess of a power law continuum, can be explained by Compton scattering of the annihilation line photons in traversing an average of approximately 21 g cm-2 of atmosphere. PMID:11537397

  19. Electromagnetic and nuclear radiation detector using micromechanical sensors

    DOEpatents

    Thundat, Thomas G.; Warmack, Robert J.; Wachter, Eric A.

    2000-01-01

    Electromagnetic and nuclear radiation is detected by micromechanical sensors that can be coated with various interactive materials. As the micromechanical sensors absorb radiation, the sensors bend and/or undergo a shift in resonance characteristics. The bending and resonance changes are detected with high sensitivity by any of several detection methods including optical, capacitive, and piezoresistive methods. Wide bands of the electromagnetic spectrum can be imaged with picoJoule sensitivity, and specific absorptive coatings can be used for selective sensitivity in specific wavelength bands. Microcantilevers coated with optical cross-linking polymers are useful as integrating optical radiation dosimeters. Nuclear radiation dosimetry is possible by fabricating cantilevers from materials that are sensitive to various nuclear particles or radiation. Upon exposure to radiation, the cantilever bends due to stress and its resonance frequency shifts due to changes in elastic properties, based on cantilever shape and properties of the coating.

  20. Effects of Nuclear Interactions on Accuracy of Space Radiation Transport

    NASA Technical Reports Server (NTRS)

    Lin, Zi-Wei; Barghouty, A. F.

    2005-01-01

    Space radiation risk to astronauts and electronic equipments is one major obstacle in long term human space explorations. Space radiation transport codes have been developed to calculate radiation effects behind materials in human missions to the Moon, Mars or beyond. We study how nuclear fragmentation processes affect the accuracy of predictions from such radiation transport. In particular, we investigate the effects of fragmentation cross sections at different energies on fluxes, dose and dose-equivalent from galactic cosmic rays behind typical shielding materials. These results tell us at what energies nuclear cross sections are the most important for radiation risk evaluations, and how uncertainties in our knowledge about nuclear fragmentations relate to uncertainties in space transport predictions.

  1. Verifying a nuclear weapon`s response to radiation environments

    SciTech Connect

    Dean, F.F.; Barrett, W.H.

    1998-05-01

    The process described in the paper is being applied as part of the design verification of a replacement component designed for a nuclear weapon currently in the active stockpile. This process is an adaptation of the process successfully used in nuclear weapon development programs. The verification process concentrates on evaluating system response to radiation environments, verifying system performance during and after exposure to radiation environments, and assessing system survivability.

  2. Is natural background or radiation from nuclear power plants leukemogenic

    SciTech Connect

    Cronkite, E.P.

    1989-01-01

    The objective in this review is to provide some facts about normal hemopoietic cell proliferation relevant to leukemogenesis, physical, chemical, and biological facts about radiation effects with the hope that each person will be able to decide for themselves whether background radiation or emissions from nuclear power plants and facilities significantly add to the spontaneous leukemia incidence. 23 refs., 1 tab.

  3. Teaching Nuclear Radiation and the Poisoning of Alexander Litvinenko

    ERIC Educational Resources Information Center

    David R. Lapp

    2008-01-01

    The recent international story about the death of the former KGB agent Alexander Litvinenko has more than just a few wondering about radiation poisoning and the sinister sounding polonium-210. I was preparing to begin a nuclear radiation unit the Monday after Thanksgiving 2006. As it turned out, Litvinenko died Thanksgiving Day after a short and…

  4. Radiation safety and nuclear medicine policies and procedures.

    PubMed

    Berman, C G

    1999-07-01

    There is a growing concern over possible adverse effects from medical applications of ionizing radiation. Hospital personnel must be educated in procedures to minimize exposure to themselves and their patients. Basic radiation safety procedures to protect personnel and patients are discussed. Examples of the nuclear medicine policies and procedures used for lymphatic mapping are provided. PMID:10448699

  5. Radiation Effects in a Model Ceramic for Nuclear Waste Disposal

    SciTech Connect

    Devanathan, Ram; Weber, William J.

    2007-04-02

    The safe immobilization of nuclear waste in geological repositories is one of the major scientific challenges facing humanity today. Crystalline ceramics hold the promise of locking up actinides from nuclear fuel and excess weapons plutonium in their structure thereby isolating them from the environment. In this paper, we discuss the atomistic details of radiation damage in a model ceramic, zircon.

  6. Radiation effects in a model ceramic for nuclear waste disposal

    NASA Astrophysics Data System (ADS)

    Devanathan, Ram; Weber, William J.

    2007-04-01

    The safe immobilization of nuclear waste in geological repositories is one of the major scientific challenges facing humanity today. Crystalline ceramics hold the promise of locking up actinides from nuclear fuel and excess weapons plutonium in their structure thereby isolating them from the environment. This paper presents the atomistic details of radiation damage in a model ceramic, zircon.

  7. Millimeter wave detection of nuclear radiation - an alternative detection mechanism.

    SciTech Connect

    Gopalsami, N.; Chien, H. T.; Heifetz, A.; Koehl, E. R.; Raptis, A. C.; Nuclear Engineering Division

    2009-08-01

    We present a nuclear radiation detection mechanism using millimeter waves as an alternative to conventional detection. It is based on the concept that nuclear radiation causes ionization of air and that if we place a dielectric material near the radiation source, it acts as a charge accumulator of the air ions. We have found that millimeter waves can interrogate the charge cloud on the dielectric material remotely. This concept was tested with a standoff millimeter wave system by monitoring the charge levels on a cardboard tube placed in an x-ray beam.

  8. Millimeter wave detection of nuclear radiation: An alternative detection mechanism

    SciTech Connect

    Gopalsami, N.; Chien, H. T.; Heifetz, A.; Koehl, E. R.; Raptis, A. C.

    2009-08-15

    We present a nuclear radiation detection mechanism using millimeter waves as an alternative to conventional detection. It is based on the concept that nuclear radiation causes ionization of air and that if we place a dielectric material near the radiation source, it acts as a charge accumulator of the air ions. We have found that millimeter waves can interrogate the charge cloud on the dielectric material remotely. This concept was tested with a standoff millimeter wave system by monitoring the charge levels on a cardboard tube placed in an x-ray beam.

  9. Millimeter wave detection of nuclear radiation: An alternative detection mechanism

    NASA Astrophysics Data System (ADS)

    Gopalsami, N.; Chien, H. T.; Heifetz, A.; Koehl, E. R.; Raptis, A. C.

    2009-08-01

    We present a nuclear radiation detection mechanism using millimeter waves as an alternative to conventional detection. It is based on the concept that nuclear radiation causes ionization of air and that if we place a dielectric material near the radiation source, it acts as a charge accumulator of the air ions. We have found that millimeter waves can interrogate the charge cloud on the dielectric material remotely. This concept was tested with a standoff millimeter wave system by monitoring the charge levels on a cardboard tube placed in an x-ray beam.

  10. Millimeter wave detection of nuclear radiation: an alternative detection mechanism.

    PubMed

    Gopalsami, N; Chien, H T; Heifetz, A; Koehl, E R; Raptis, A C

    2009-08-01

    We present a nuclear radiation detection mechanism using millimeter waves as an alternative to conventional detection. It is based on the concept that nuclear radiation causes ionization of air and that if we place a dielectric material near the radiation source, it acts as a charge accumulator of the air ions. We have found that millimeter waves can interrogate the charge cloud on the dielectric material remotely. This concept was tested with a standoff millimeter wave system by monitoring the charge levels on a cardboard tube placed in an x-ray beam. PMID:19725673

  11. Teaching Nuclear Radiation and the Poisoning of Alexander Litvinenko

    NASA Astrophysics Data System (ADS)

    Lapp, David R.

    2008-03-01

    The recent international story about the death of the former KGB agent Alexander Litvinenko has more than just a few wondering about radiation poisoning and the sinister sounding polonium-210. I was preparing to begin a nuclear radiation unit the Monday after Thanksgiving 2006. As it turned out, Litvinenko died Thanksgiving Day after a short and terrible three-week illness. Having the story continue to unfold throughout the next two weeks of the new unit provided a daily opportunity for students to see the relevance of what we were doing in class. My students were able to have meaningful and informed conversations with their peers and parents over an important international event. They even began to feel a bit like authorities themselves when listening to experts respond to media questions about polonium-210 and nuclear radiation in general. This paper discusses some of the ways that the story of Litvinenko was used while presenting the topic of nuclear radiation.

  12. Recent measurements for hadrontherapy and space radiation: nuclear physics

    NASA Technical Reports Server (NTRS)

    Miller, J.

    2001-01-01

    The particles and energies commonly used for hadron therapy overlap the low end of the charge and energy range of greatest interest for space radiation applications, Z=1-26 and approximately 100-1000 MeV/nucleon. It has been known for some time that the nuclear interactions of the incident ions must be taken into account both in treatment planning and in understanding and addressing the effects of galactic cosmic ray ions on humans in space. Until relatively recently, most of the studies of nuclear fragmentation and transport in matter were driven by the interests of the nuclear physics and later, the hadron therapy communities. However, the experimental and theoretical methods and the accelerator facilities developed for use in heavy ion nuclear physics are directly applicable to radiotherapy and space radiation studies. I will briefly review relevant data taken recently at various accelerators, and discuss the implications of the measurements for radiotherapy, radiobiology and space radiation research.

  13. Applications of nuclear data in human radiation dosimetry

    SciTech Connect

    Kerr, G.D.; Eckerman, K.F. )

    1991-01-01

    Individuals are exposed to ionizing radiations in two ways: from radiation sources external to the body or from internal sources. In either case, the magnitude of the radiation dose to the sensitive tissues of the body is of primary concern. Radiation dose (or absorbed dose) is a physical quantity defined as the amount of ionizing energy absorbed per unit mass of material. For radiation protection purposes, however, it is also necessary to use the dose equivalent, which includes modifiers of absorbed dose to more fully reflect the biological considerations associated with different ionizing radiations. A research group at Oak Ridge National Laboratory has focused on defining the exposure-dose relationship (i.e., the relationship between radiation exposure from internal or external sources and the radiation dose received by tissues of the body). Although radiation can be readily detected and measured, it is not feasible to make direct measurements of the dose within the organs and tissues of the body. Nuclear data have been extensively used in these studies but improvements are needed in the current nuclear data base. Examples of these applications include studies dealing with (a) the application of the recommendations of Publication 26 of the International Committee on Radiological Protection in the dosimetry of internally deposited radionuclides and (b) the reassessment of radiation dosimetry for the atomic bombs in Hiroshima and Nagasaki.

  14. RADIATION EFFECTS IN NUCLEAR WASTE MATERIALS

    EPA Science Inventory

    The objective of this multidisciplinary, multi-institutional research effort is to develop a fundamental understanding at the atomic, microscopic, and macroscopic levels of radiation effects in glass and ceramics that provides the underpinning science and models for evaluation an...

  15. What Students Think About (Nuclear) Radiation - Before and After Fukushima

    NASA Astrophysics Data System (ADS)

    Neumann, S.

    2014-06-01

    Preparing successful science lessons is very demanding. One important aspect a teacher has to consider is the students' previous knowledge about the specific topic. This is why research about students' preconceptions has been, and continues to be, a major field in science education research. Following a constructivistic approach [R. Duit et al., International handbook of research on conceptual change, p. 629 (2008)], helping students learn is only possible if teachers know about students' ideas beforehand. Studies about students' conceptions regarding the major topics in physics education (e.g. mechanics, electrodynamics, optics, thermodynamics), are numerous and well-documented. The topic radiation, however, has seen very little empirical research about students' ideas and misconceptions. Some research was conducted after the events of Chernobyl [P. Lijnse et al., International Journal of Science Education 12, 67 (1990); B. Verplanken, Environment and Behavior 21, 7 (1989)] and provided interesting insight into some of the students' preconceptions about radiation. In order to contribute empirical findings to this field of research, our workgroup has been investigating the conceptions students have about the topic radiation for several years [S. Neumann et al., Journal of Science Education and Technology 21, 826 (2012)]. We used children's drawings and conducted short follow-up interviews with students (9 - 12 years old) and more detailed interviews with 15-year-old students. Both studies were originally done before the events in Fukushima and replicated a year later. We not only asked students about their general associations and emotions regarding the term radiation, but also examined the students' risk perceptions of different types of radiation. Through the use of open-ended questions we were able to examine students' conceptions about different types of radiation (including nuclear) that could be a hindrance to student learning. Our results show that students

  16. Nuclear medicine and the environment: radiation interactions.

    PubMed

    Schmelter, R F

    1986-04-01

    The effect of radiation interactions on the environment may be considered from the perspective of the purely physical phenomena occurring or from the effects the interactions produce in organized biological systems. The physical processes by which radiation interacts with the environment are quite well defined. Although these processes differ depending upon the nature (either electromagnetic or particulate) of the primary radiation, the ultimate result is the production in the medium of high-speed, secondary charged particles. Some of the energy of these particles is absorbed by the medium, while a portion may be lost as bremsstrahlung. The energy that is absorbed produces excitation and ionization, which can be disruptive to biological systems. The effects produced by ionizing radiations at the biochemical, cellular, and organ level are less well defined. Nevertheless, available data indicate that certain generalizations are possible. For example, given the ubiquitous nature of water in tissues, macromolecules, regardless of their structural types, tend to serve as acceptors of the energy and products of water radiolysis. However, a deeper insight into the consequences of irradiation requires an understanding of the interplay of such parameters as the type and energy of the radiation, and the dose and rate of its application. Furthermore, at the cellular level, the type and age of the irradiated cells, the concentration of oxygen in their environment, and their cell-cycle phase are all important factors in determining the consequences of irradiation. PMID:3515567

  17. Nuclear radiation-warning detector that measures impedance

    SciTech Connect

    Savignac, Noel Felix; Gomez, Leo S; Yelton, William Graham; Robinson, Alex; Limmer, Steven

    2013-06-04

    This invention is a nuclear radiation-warning detector that measures impedance of silver-silver halide on an interdigitated electrode to detect light or radiation comprised of alpha particles, beta particles, gamma rays, X rays, and/or neutrons. The detector is comprised of an interdigitated electrode covered by a layer of silver halide. After exposure to alpha particles, beta particles, X rays, gamma rays, neutron radiation, or light, the silver halide is reduced to silver in the presence of a reducing solution. The change from the high electrical resistance (impedance) of silver halide to the low resistance of silver provides the radiation warning that detected radiation levels exceed a predetermined radiation dose threshold.

  18. Radiation effects on organic materials in nuclear plants. Final report

    SciTech Connect

    Bruce, M B; Davis, M V

    1981-11-01

    A literature search was conducted to identify information useful in determining the lowest level at which radiation causes damage to nuclear plant equipment. Information was sought concerning synergistic effects of radiation and other environmental stresses. Organic polymers are often identified as the weak elements in equipment. Data on radiation effects are summarized for 50 generic name plastics and 16 elastomers. Coatings, lubricants, and adhesives are treated as separate groups. Inorganics and metallics are considered briefly. With a few noted exceptions, these are more radiation resistant than organic materials. Some semiconductor devices and electronic assemblies are extremely sensitive to radiation. Any damage threshold including these would be too low to be of practical value. With that exception, equipment exposed to less than 10/sup 4/ rads should not be significantly affected. Equipment containing no Teflon should not be significantly affected by 10/sup 5/ rads. Data concerning synergistic effects and radiation sensitization are discussed. The authors suggest correlations between the two effects.

  19. Nuclear Fragmentation Processes Relevant for Human Space Radiation Protection

    NASA Technical Reports Server (NTRS)

    Lin, Zi-Wei

    2007-01-01

    Space radiation from cosmic ray particles is one of the main challenges for human space explorations such-as a moon base or a trip to Mars. Models have been developed in order to predict the radiation exposure to astronauts and to evaluate the effectiveness of different shielding materials, and a key ingredient in these models is the physics of nuclear fragmentations. We have developed a semi-analytical method to determine which partial cross sections of nuclear fragmentations most affect the radiation dose behind shielding materials due to exposure to galactic cosmic rays. The cross sections thus determined will require more theoretical and/or experimental studies in order for us to better predict, reduce and mitigate the radiation exposure in human space explorations.

  20. Impact of radiation dose on nuclear shuttle configuration

    NASA Technical Reports Server (NTRS)

    Goetz, C. A.; Billings, M. A.

    1972-01-01

    The impact of nuclear radiation (from the NERVA propulsion system) on the selection of a reference configuration for each of two classes of the reusable nuclear shuttle is considered. One class was characterized by a single propellant tank, the shape of whose bottom was found to have a pronounced effect on crew radiation levels and associated shield weight requirements. A trade study of shield weight versus structural weight indicated that the minimum-weight configuration for this class had a tank bottom in the shape of a frustum of a 10 deg-half-angle cone. A hybrid version of this configuration was found to affect crew radiation levels in substantially the same manner. The other class of RNS consisted of a propulsion module and eight propellant modules. Radiation analyses of various module arrangements led to a design configuration with no external shield requirements.

  1. Radiation and Nuclear Materials Detection Research and Development at ORNL

    SciTech Connect

    Hardy, Jim E; Wright, Michael C

    2009-01-01

    Research and development is underway to improve radiation and nuclear detection capabilities. This research and development in radiation and nuclear detection includes areas such as advanced materials, applied research and engineering for designing and fabricating customized detection equipment, and theoretical modeling and computational support. Oak Ridge National Laboratory (ORNL) has a distinctive set of detector materials fabrication and characterization capabilities and recently created a Center for Radiation Detection Materials and Systems. Applied research and engineering efforts have led to the development of improved detectors for specific applications including safeguards, treaty monitoring, and science experiments. All sizes, types, and capabilities of detector systems have been addressed from miniature to man-portable and from neutrons to gamma radiation. Dedicated test beds, in-house and in the field, have been established to analyze, characterize, and improve detection systems.

  2. Increased occupational radiation doses: nuclear fuel cycle.

    PubMed

    Bouville, André; Kryuchkov, Victor

    2014-02-01

    The increased occupational doses resulting from the Chernobyl nuclear reactor accident that occurred in Ukraine in April 1986, the reactor accident of Fukushima that took place in Japan in March 2011, and the early operations of the Mayak Production Association in Russia in the 1940s and 1950s are presented and discussed. For comparison purposes, the occupational doses due to the other two major reactor accidents (Windscale in the United Kingdom in 1957 and Three Mile Island in the United States in 1979) and to the main plutonium-producing facility in the United States (Hanford Works) are also covered but in less detail. Both for the Chernobyl nuclear reactor accident and the routine operations at Mayak, the considerable efforts made to reconstruct individual doses from external irradiation to a large number of workers revealed that the recorded doses had been overestimated by a factor of about two.Introduction of Increased Occupational Exposures: Nuclear Industry Workers. (Video 1:32, http://links.lww.com/HP/A21). PMID:24378501

  3. Estimates of the radiation environment for a nuclear rocket engine

    SciTech Connect

    Courtney, J.C.; Manohara, H.M.; Williams, M.L.

    1992-12-31

    Ambitious missions in deep space, such as manned expeditions to Mars, require nuclear propulsion if they are to be accomplished in a reasonable length of time. Current technology is adequate to support the use of nuclear fission as a source of energy for propulsion; however, problems associated with neutrons and gammas leaking from the rocket engine must be addressed. Before manned or unmanned space flights are attempted, an extensive ground test program on the rocket engine must be completed. This paper compares estimated radiation levels and nuclear heating rates in and around the rocket engine for both a ground test and space environments.

  4. Nuclear model calculations and their role in space radiation research

    NASA Technical Reports Server (NTRS)

    Townsend, L. W.; Cucinotta, F. A.; Heilbronn, L. H.

    2002-01-01

    Proper assessments of spacecraft shielding requirements and concomitant estimates of risk to spacecraft crews from energetic space radiation requires accurate, quantitative methods of characterizing the compositional changes in these radiation fields as they pass through thick absorbers. These quantitative methods are also needed for characterizing accelerator beams used in space radiobiology studies. Because of the impracticality/impossibility of measuring these altered radiation fields inside critical internal body organs of biological test specimens and humans, computational methods rather than direct measurements must be used. Since composition changes in the fields arise from nuclear interaction processes (elastic, inelastic and breakup), knowledge of the appropriate cross sections and spectra must be available. Experiments alone cannot provide the necessary cross section and secondary particle (neutron and charged particle) spectral data because of the large number of nuclear species and wide range of energies involved in space radiation research. Hence, nuclear models are needed. In this paper current methods of predicting total and absorption cross sections and secondary particle (neutrons and ions) yields and spectra for space radiation protection analyses are reviewed. Model shortcomings are discussed and future needs presented. c2002 COSPAR. Published by Elsevier Science Ltd. All right reserved.

  5. Nuclear model calculations and their role in space radiation research.

    PubMed

    Townsend, L W; Cucinotta, F A; Heilbronn, L H

    2002-01-01

    Proper assessments of spacecraft shielding requirements and concomitant estimates of risk to spacecraft crews from energetic space radiation requires accurate, quantitative methods of characterizing the compositional changes in these radiation fields as they pass through thick absorbers. These quantitative methods are also needed for characterizing accelerator beams used in space radiobiology studies. Because of the impracticality/impossibility of measuring these altered radiation fields inside critical internal body organs of biological test specimens and humans, computational methods rather than direct measurements must be used. Since composition changes in the fields arise from nuclear interaction processes (elastic, inelastic and breakup), knowledge of the appropriate cross sections and spectra must be available. Experiments alone cannot provide the necessary cross section and secondary particle (neutron and charged particle) spectral data because of the large number of nuclear species and wide range of energies involved in space radiation research. Hence, nuclear models are needed. In this paper current methods of predicting total and absorption cross sections and secondary particle (neutrons and ions) yields and spectra for space radiation protection analyses are reviewed. Model shortcomings are discussed and future needs presented. PMID:12539757

  6. Radiation protection performance indicators at the Nuclear Power Plant Krsko.

    PubMed

    Janzekovic, Helena

    2006-06-01

    Nuclear power plant safety performance indicators are developed "by nuclear operating organisations to monitor their own performance and progress, to set their own challenging goals for improvement, and to gain additional perspective on performance relative to that of other plants". In addition, performance indicators are widely used by regulatory authorities although the use is not harmonised. Two basic performance indicators related to good radiation protection practice are collective radiation exposure and volume of low-level radioactive waste. In 2000, Nuclear Power Plant Krsko, a Westinghouse pressurised water reactor with electrical output 700 MW, finished an extensive modernisation including the replacement of both steam generators. While the annual volume of low-level radioactive waste does not show a specific trend related to modernisation, the annual collective dose reached maximum, i.e. 2.60 man Sv, and dropped to 1.13 man Sv in 2001. During the replacement of the steam generators in 2000, the dose associated with this activity was 1.48 man Sv. The annual doses in 2002 and 2003 were 0.53 and 0.80 man Sv, respectively, nearing thus the goal set by the US Institute of Nuclear Power Operators, which is 0.65 man Sv. Therefore, inasmuch as collective dose as the radiation protection performance indicator are concerned, the modernisation of the Krsko nuclear power plant was a success. PMID:16832974

  7. Radiation imaging technology for nuclear materials safeguards

    SciTech Connect

    Prettyman, T.H.; Russo, P.A.; Cheung, C.C.; Christianson, A.D.; Feldman, W.C.; Gavron, A.

    1997-12-01

    Gamma-ray and neutron imaging technology is emerging as a useful tool for nuclear materials safeguards. Principal applications include improvement in accuracy for nondestructive assay of heterogeneous material (e.g., residues) and wide-area imaging of nuclear material in facilities (e.g., holdup). Portable gamma cameras with gamma-ray spectroscopy are available commercially and are being applied to holdup measurements. The technology has the potential to significantly reduce effort and exposure in holdup campaigns; and, with imaging, some of the limiting assumptions required for conventional holdup analysis can be relaxed, resulting in a more general analysis. Methods to analyze spectroscopic-imaging data to assay plutonium and uranium in processing equipment are being development. Results of holdup measurements using a commercial, portable gamma-cameras are presented. The authors are also developing fast neutron imaging techniques for NDA, search, and holdup. Fast neutron imaging provides a direct measurement of the source of neutrons and is relatively insensitive to surroundings when compared to thermal or epithermal neutron imaging. The technology is well-suited for in-process inventory measurements and verification of materials in interim storage, for which gamma-ray measurements may be inadequate due to self-shielding. Results of numerical simulations to predict the performance of fast-neutron telescopes for safeguards applications are presented.

  8. Calibration of radiation monitors at nuclear power plants. Final report

    SciTech Connect

    Boudreau, L.; Miller, A.D.; Naughton, M.D.

    1994-03-01

    This work was performed to provide guidance to the utilities in the primary and secondary calibration of the radiation monitoring systems (RMS) installed in nuclear power plants. These systems are installed in nuclear power plants to monitor ongoing processes, identify changing radiation fields, predict and limit personnel radiation exposures and measure and control discharge of radioactive materials to the environment. RMS are checked and calibrated on a continuing basis to ensure their precision and accuracy. This report discusses various approaches towards primary and secondary calibrations of the RMS equipment in light of accepted practices at typical power plants and recent interpretations of regulatory guidance. Detailed calibration techniques and overall system responses, trends, and practices are discussed. Industry, utility, and regulatory sources were contacted to create an overall consensus of the most reasonable approaches to optimizing the performance of this equipment.

  9. Radiation and Thermal Ageing of Nuclear Waste Glass

    SciTech Connect

    Weber, William J

    2014-01-01

    The radioactive decay of fission products and actinides incorporated into nuclear waste glass leads to self-heating and self-radiation effects that may affect the stability, structure and performance of the glass in a closed system. Short-lived fission products cause significant self-heating for the first 600 years. Alpha decay of the actinides leads to self-radiation damage that can be significant after a few hundred years, and over the long time periods of geologic disposal, the accumulation of helium and radiation damage from alpha decay may lead to swelling, microstructural evolution and changes in mechanical properties. Four decades of research on the behavior of nuclear waste glass are reviewed.

  10. Thermal Radiation from Nuclear Detonations in Urban Environments

    SciTech Connect

    Marrs, R E; Moss, W C; Whitlock, B

    2007-06-04

    There are three principal causes of ''prompt'' casualties from a nuclear detonation: nuclear (gamma-ray and neutron) radiation, thermal radiation, and blast. Common estimates of the range of these prompt effects indicate that thermal radiation has the largest lethal range [1]. Non-lethal skin burns, flash blindness, and retinal burns occur out to much greater range. Estimates of casualties from thermal radiation assume air bursts over flat terrain. In urban environments with multiple buildings and terrain features, the extent of thermal radiation may be significantly reduced by shadowing. We have developed a capability for calculating the distribution of thermal energy deposition in urban environments using detailed 3D computer models of actual cities. The size, height, and radiated power from the fireball as a function of time are combined with ray tracing to calculate the energy deposition on all surfaces. For surface bursts less than 100 kt in locations with large buildings or terrain features, the calculations confirm the expected reduction in thermal damage.

  11. Effects of radiation environment on reusable nuclear shuttle system

    NASA Technical Reports Server (NTRS)

    Lane, A. G.

    1972-01-01

    Parametric tradeoff analyses of a wide spectrum of alternate tank configurations to minimize both primary and secondary, direct and scattered radiation sources emanating from the NERVA are reported. The analytical approach utilizing point kernel techniques is described and detailed data are presented on the magnitude of neutron/gamma doses for different locations. Single-tank configurations utilizing smaller cone angles and end cap radii were found to minimize integral radiation levels, hence, stage shielding-weight penalties for shuttle missions. Hybrid configurations employing an upper tank with a reduced cone angle and end cap radius result in low integral payload doses primarily due to the increased separation distance caused by the elongation of the larger capacity upper tank. A preliminary radiation damage assessment is discussed of possible reusable nuclear shuttle materials, components, and subsystems, and the possible effects of the radiation environment on various phases of RNS mission operations.

  12. Institutional Radiation Safety Committee--Nuclear Regulatory Commission. Final rule.

    PubMed

    1982-09-13

    The Nuclear Regulatory Commission (NRC) is amending its regulations regarding hospitals licensed to use radioactive byproduct material for human applications. Currently, such a license requires that the hospital have a Medical Isotopes Committee to review clinical aspects of the use of radioactive materials within the hospital. The amendment requires instead a Radiation Safety Committee with a simplified membership that will focus on the radiation safety of workers and the general public. The rule change acknowledges the Food and Drug Administration's role in regulating the safety and effectiveness of radioactive drugs with respect to the patient. The membership of the new Radiation Safety Committee will include the hospital management and the nursing staff in decisions affecting radiation safety at the hospital and will be easier for smaller hospitals to recruit. PMID:10259789

  13. R&D for Better Nuclear Security: Radiation Detector Materials

    SciTech Connect

    Kammeraad, J E

    2009-04-02

    I am going to talk about the need for better materials for radiation detectors. I believe that government investment in this area can enable transformational technology change that could impact domestic nuclear security and also national nuclear security in some very positive and powerful ways. I'm not going to give you a lecture on how radiation detectors work, but I am going to tell you a bit about today's off-the-shelf technology and why it is not sufficient, what we need, and what security benefit you could get from improvements. I think we're at a critical point in time for some very impactful investments. In particular I'm going to focus on the use of gamma-ray radiation detectors at ports of entry. Not long before DHS was formed, Congress decreed that counter measures against the delivery of radiological and nuclear threats would be put in place at US ports of entry, under the authority of US Customs (later Customs and Border Protection in DHS). This included the screening of all cars and trucks passing through a port of entry. Existing off-the-shelf radiation detectors had to be selected for this purpose. Plans were made to make the most of the available technologies, but there are some inherent limitations of these detectors, plus the operational setting can bring out other limitations.

  14. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    SciTech Connect

    Fabrikant, J.I.

    1981-05-01

    The current knowledge of the carcinogenic effect of radiation in man is considered. The discussion is restricted to dose-incidence data in humans, particularly to certain of those epidemiological studies of human populations that are used most frequently for risk estimation for low-dose radiation carcinogenesis in man. Emphasis is placed solely on those surveys concerned with nuclear explosions and medical exposures. (ACR)

  15. Radiation safety in the nuclear medicine department: impact of the UK Ionising Radiations Regulations.

    PubMed

    Harding, L K

    1987-09-01

    The practice of nuclear medicine requires integration of radiation safety with patient care and radiopharmaceutical standards. Nationally there was useful discussion in the UK before the Ionising Radiations Regulations and Approved Code of Practice were published, although such consultation had been lacking when the Medicines Act was implemented. Most of the new considerations relating to nuclear medicine stem from Schedule 6 of the Regulations. Generally, the presence of a single patient does not require a controlled area. However, when several patients are present, or radiopharmaceuticals are being prepared prior to injection, a controlled area is required. Classification of workers is not likely to be required in a typical nuclear medicine department in the UK, although most parts of the nuclear medicine department will need to be controlled areas. These include the radiopharmacy, radionuclide dispensary, injection room, and imaging rooms if patients are injected in them. The importance of finger dose measurements is emphasised. Patient wards, however, need not be controlled areas. A particular concern in nuclear medicine was that patients should not need to be admitted to hospital merely to comply with legislation. This is possibly the case and clarification will probably be available when the Notes for Guidance are published. Most procedures in nuclear medicine departments will remain unchanged. Further information is required, however, on patient waiting rooms, handling flood sources, pregnancy, and breast feeding. Within the hospital, detailed and multidisciplinary discussion will need to take place within the forum of the radiation safety committee. PMID:3664186

  16. Radiation induced corrosion of copper for spent nuclear fuel storage

    NASA Astrophysics Data System (ADS)

    Björkbacka, Åsa; Hosseinpour, Saman; Johnson, Magnus; Leygraf, Christofer; Jonsson, Mats

    2013-11-01

    The long term safety of repositories for radioactive waste is one of the main concerns for countries utilizing nuclear power. The integrity of engineered and natural barriers in such repositories must be carefully evaluated in order to minimize the release of radionuclides to the biosphere. One of the most developed concepts of long term storage of spent nuclear fuel is the Swedish KBS-3 method. According to this method, the spent fuel will be sealed inside copper canisters surrounded by bentonite clay and placed 500 m down in stable bedrock. Despite the importance of the process of radiation induced corrosion of copper, relatively few studies have been reported. In this work the effect of the total gamma dose on radiation induced corrosion of copper in anoxic pure water has been studied experimentally. Copper samples submerged in water were exposed to a series of total doses using three different dose rates. Unirradiated samples were used as reference samples throughout. The copper surfaces were examined qualitatively using IRAS and XPS and quantitatively using cathodic reduction. The concentration of copper in solution after irradiation was measured using ICP-AES. The influence of aqueous radiation chemistry on the corrosion process was evaluated based on numerical simulations. The experiments show that the dissolution as well as the oxide layer thickness increase upon radiation. Interestingly, the evaluation using numerical simulations indicates that aqueous radiation chemistry is not the only process driving the corrosion of copper in these systems.

  17. Compton Radiation for Nuclear Waste Management and Transmutation

    NASA Astrophysics Data System (ADS)

    Bulyak, E.; Urakawa, J.

    2015-10-01

    Compton inverse radiation is emitted in the process of backscattering of the laser pulses off the relativistic electrons. This radiation possesses high spectral density and high energy of photons--in hard x-ray up to gammaray energy range--with moderate electron energies (hundreds of MeV up to 1 GeV) due to short wavelength of the laser radiation. The Compton radiation is well collimated: emitting within a narrow cone along the electron beam. A distinct property of the Compton inverse radiation is a steep high-energy cutoff of the spectrum and the maximal intensity just below the cutoff. The Compton sources can attain: spectral density up to 1014 gammas/(s 0.1%bandwidth) in MeV range of energies, and spectral brightness up to 1020 gammas/(smm2mr2 0.1% bw). Applicability of Compton sources for nuclear waste management and detection of radioisotopes and fissionable nuclides are discussed in the report. Also application limits of Compton gamma sources for transmutation of radioactive isotopes are estimated. A recently proposed subtracting method, in which two sets of data obtained by irradiating the object by the Compton beams with slightly different maximal energies are compared, will enhance resolution of detection radioactive elements at the 'atomic' (hundreds of keV) and the 'nuclear' (a few MeV) photon energies.

  18. DNA-nuclear matrix interactions and ionizing radiation sensitivity

    SciTech Connect

    Schwartz, J.L. Chicago Univ., IL . Dept. of Radiation and Cellular Oncology); Vaughan, A.T.M. . Dept. of Radiotherapy)

    1993-01-01

    The association between inherent ionizing radiation sensitivity and DNA supercoil unwinding in mammalian cells suggests that the DNA-nuclear matrix attachment region (MAR) plays an important role in radiation response. In radioresistant cells, the MAR structure may exist in a more stable, open configuration, limiting DNA unwinding following strand break induction and maintaining DNA ends in close proximity for more rapid and accurate rejoining. In addition, the open configuration at these matrix attachment sites may serve to facilitate rapid DNA processing of breaks by providing (1) sites for repair proteins to collect and (2) energy to drive enzymatic reactions.

  19. DNA-nuclear matrix interactions and ionizing radiation sensitivity

    SciTech Connect

    Schwartz, J.L. |; Vaughan, A.T.M.

    1993-03-01

    The association between inherent ionizing radiation sensitivity and DNA supercoil unwinding in mammalian cells suggests that the DNA-nuclear matrix attachment region (MAR) plays an important role in radiation response. In radioresistant cells, the MAR structure may exist in a more stable, open configuration, limiting DNA unwinding following strand break induction and maintaining DNA ends in close proximity for more rapid and accurate rejoining. In addition, the open configuration at these matrix attachment sites may serve to facilitate rapid DNA processing of breaks by providing (1) sites for repair proteins to collect and (2) energy to drive enzymatic reactions.

  20. Lightweight Radiator for in Space Nuclear Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Craven, Paul; Tomboulian, Briana; SanSoucie, Michael

    2014-01-01

    Nuclear electric propulsion (NEP) is a promising option for high-speed in-space travel due to the high energy density of nuclear fission power sources and efficient electric thrusters. Advanced power conversion technologies may require high operating temperatures and would benefit from lightweight radiator materials. Radiator performance dictates power output for nuclear electric propulsion systems. Game-changing propulsion systems are often enabled by novel designs using advanced materials. Pitch-based carbon fiber materials have the potential to offer significant improvements in operating temperature, thermal conductivity, and mass. These properties combine to allow advances in operational efficiency and high temperature feasibility. An effort at the NASA Marshall Space Flight Center to show that woven high thermal conductivity carbon fiber mats can be used to replace standard metal and composite radiator fins to dissipate waste heat from NEP systems is ongoing. The goals of this effort are to demonstrate a proof of concept, to show that a significant improvement of specific power (power/mass) can be achieved, and to develop a thermal model with predictive capabilities making use of constrained input parameter space. A description of this effort is presented.

  1. Modeling of radiation effects on nuclear waste package materials

    SciTech Connect

    Simonson, S.A.

    1988-09-01

    A methodology is developed for the assessment of radiation effects on nuclear waste package materials. An assessment of the current status of understanding with regard to waste package materials and their behavior in radiation environments is presented. The methodology is used to make prediction as to the chemically induced changes in the groundwater surrounding nuclear waste packages in a repository in tuff. The predictions indicate that mechanisms not currently being pursued by the Department of Energy may be a factor in the long-term performance of nuclear waste packages. The methodology embodies a physical model of the effects of radiation on aqueous solutions. Coupled to the physical model is a method for analyzing the complex nature of the physical model using adjoint sensitivity analysis. The sensitivity aid in both the physical understanding of the processes involved as well as aiding in eliminating portions of the model that have no bearing on the desired results. A computer implementation of the methodology is provided. 128 refs.

  2. Recovery of male fertility after sterilization by nuclear radiation.

    PubMed

    Macleod, J; Hotchkiss, R S; Sitterson, B W

    1964-02-29

    The potential fertility of 6 of 8 men accidentally exposed to radiation on June 16, 1958, was studied over a 3 1/2-year period. It is clear that, as measured by semen quality, evidence of recovery of spermatogenesis may be expected within 21 months, although the sperm counts at this time will probably not be consonant with a reasonable level of fertility. A satisfactory level of fertility will be reached by 30 months and a normal level by 41 months. Review of the male fertility data on the recorded cases of less than lethal nuclear radiation accidents shows that relatively small amounts of radiation will produce pronounced effects on the testes, including disturbances in the morphology of the few spermatozoa present in the ejaculate, but that ultimate recovery of some degree of fertility is possible in most cases. PMID:12255104

  3. Review of Nuclear Physics Experiments for Space Radiation

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Miller, Jack; Adamczyk, Anne M.; Heilbronn, Lawrence H.; Townsend, Lawrence W.; Blattnig, Steve R.; Norman, Ryan B.; Guetersloh, Stephen B.; Zeitlin, Cary J.

    2011-01-01

    Human space flight requires protecting astronauts from the harmful effects of space radiation. The availability of measured nuclear cross section data needed for these studies is reviewed in the present paper. The energy range of interest for radiation protection is approximately 100 MeV/n to 10 GeV/n. The majority of data are for projectile fragmentation partial and total cross sections, including both charge changing and isotopic cross sections. The cross section data are organized into categories which include charge changing, elemental, isotopic for total, single and double differential with respect to momentum, energy and angle. Gaps in the data relevant to space radiation protection are discussed and recommendations for future experiments are made.

  4. Nonisotropic radiation of the 2013 North Korean nuclear explosion

    NASA Astrophysics Data System (ADS)

    Vavryčuk, Václav; Kim, So Gu

    2014-10-01

    On 12 February 2013, North Korea conducted an underground nuclear test in the northeastern mountainous part of the country. The explosion reached magnitude mb = 5.1 being recorded at most of seismic stations around the world and becoming one of the best ever recorded nuclear explosions in history. Similarly, as other nuclear explosions buried in Nevada, Kazakhstan, or China, the 2013 North Korean explosion is characterized by a significant nonisotropic radiation. This radiation is manifested by distinct SH and Love waves in the wave field and is inconsistent with the model of a spherically symmetric source. We show that the Love waves are not generated by a tectonic earthquake triggered on a nearby fault structures but produced by asymmetry of the explosive source caused by presence of deviatoric stress in the surrounding rock. The retrieved moment tensor of the 2013 explosion is characterized by the isotropic component of 57 ± 5%, the double-couple component of 17 ± 9%, and the compensated linear vector dipole component of 24 ± 7%. The P, T, and N axes of the moment tensor are consistent with the principal axes of the regional tectonic stress in the Korean Peninsula. A comparison of waveforms and particle motions of the 2013 explosion and the previous North Korean nuclear explosion buried in 2009 indicates that the 2013 explosion was slightly more nonisotropic.

  5. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    SciTech Connect

    Fabrikant, J.I.

    1982-08-01

    The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer-induction in man. Reference is made to dose-incidence relationships from laboratory animal experiments where they may obtain for problems and difficulties in extrapolation from data obtained at high doses to low doses, and from animal data to the human situation. The paper describes the methods of application of such epidemiological data for estimation of excess risk of radiation-induced cancer in exposed human populations, and discusses the strengths and limitations of epidemiology in guiding radiation protection philosophy and public health policy.

  6. Nuclear data needs for radiation protection and therapy dosimetry

    SciTech Connect

    Chadwick, M.B.; DeLuca, P.M. Jr.; Haight, R.C.

    1995-12-31

    New nuclear data are required for improved neutron and proton radiotherapy treatment planning as well as future applications of high-energy particle accelerators. Modern neutron radiotherapy employs energies extending to 70 MeV, while industrial applications such as transmutation and tritium breeding may generate neutrons exceeding energies of 100 MeV. Secondary neutrons produced by advanced proton therapy facilities can have energies as high as 250 MeV. Each use requires nuclear data for transport calculations and analysis of radiation effects (dosimetry). We discuss the nuclear data needs supportive of these applications including the different information requirements. As data in this energy region are sparse and likely to remain so, advanced nuclear model calculations can provide some of the needed information. ln this context, we present new evaluated nuclear data for C, N, and O. Additional experimental information, including integral and differential data, are required to confirm these results and to bound further calculations. We indicate the required new data to be measured and the difficulties in carrying out such experiments.

  7. Ionizing radiations, underground world and nuclear tests in Algeria

    NASA Astrophysics Data System (ADS)

    Chama, Allel

    2010-05-01

    Today, the exposure to ionizing radiations, is still a real great physical hazard in the world at various levels until the nuclear tests which led to a rich and lawful debate, and needs the installation of preventive rules through technical and medical aspects during the use of the radioactive sources, (theradioprotection). Concerning the occupational health, the pathology of the ionizing radiations is repaired under occupational disease. Our interest is to highlight this physical hazard, which represents an important chapter of the occupational pathology in its effects and prevention of the workers exposed in Algeria. The second aim of the paper is to highlight the historical aspect of the risk of ionizing radiations and consequences causes by the French nuclear tests in In Eker (underground galleries of the mountain of Hoggar in the south of Algeria in 1961), whose effects present a great damage on the health of the Algerian captive, and "workers", indigenous population and environment until now. This event deserves its place as much as that of Hiroshima and Nagasaki (1945).

  8. Design of radiation resistant metallic multilayers for advanced nuclear systems

    SciTech Connect

    Zhernenkov, Mikhail E-mail: gills@bnl.gov; Gill, Simerjeet E-mail: gills@bnl.gov; Stanic, Vesna; DiMasi, Elaine; Kisslinger, Kim; Ecker, Lynne; Baldwin, J. Kevin; Misra, Amit; Demkowicz, M. J.

    2014-06-16

    Helium implantation from transmutation reactions is a major cause of embrittlement and dimensional instability of structural components in nuclear energy systems. Development of novel materials with improved radiation resistance, which is of the utmost importance for progress in nuclear energy, requires guidelines to arrive at favorable parameters more efficiently. Here, we present a methodology that can be used for the design of radiation tolerant materials. We used synchrotron X-ray reflectivity to nondestructively study radiation effects at buried interfaces and measure swelling induced by He implantation in Cu/Nb multilayers. The results, supported by transmission electron microscopy, show a direct correlation between reduced swelling in nanoscale multilayers and increased interface area per unit volume, consistent with helium storage in Cu/Nb interfaces in forms that minimize dimensional changes. In addition, for Cu/Nb layers, a linear relationship is demonstrated between the measured depth-dependent swelling and implanted He density from simulations, making the reflectivity technique a powerful tool for heuristic material design.

  9. Evaluation of Radiation Impacts of Spent Nuclear Fuel Storage (SNFS-2) of Chernobyl NPP - 13495

    SciTech Connect

    Paskevych, Sergiy; Batiy, Valiriy; Sizov, Andriy; Schmieman, Eric

    2013-07-01

    Radiation effects are estimated for the operation of a new dry storage facility for spent nuclear fuel (SNFS-2) of Chernobyl NPP RBMK reactors. It is shown that radiation exposure during normal operation, design and beyond design basis accidents are minor and meet the criteria for safe use of radiation and nuclear facilities in Ukraine. (authors)

  10. THE RADIATION SAFETY INFORMATION COMPUTATIONAL CENTER: A RESOURCE FOR REACTOR DOSIMETRY SOFTWARE AND NUCLEAR DATA

    SciTech Connect

    Kirk, Bernadette Lugue

    2009-01-01

    The Radiation Safety Information Computational Center (RSICC) was established in 1963 to collect and disseminate computational nuclear technology in the form of radiation transport, shielding and safety software and corresponding nuclear cross sections. Approximately 1700 nuclear software and data packages are in the RSICC collection, and the majority are applicable to reactor dosimetry.

  11. The Radiation Safety Information Computational Center:. a Resource for Reactor Dosimetry Software and Nuclear Data

    NASA Astrophysics Data System (ADS)

    Kirk, B. L.

    2009-08-01

    The Radiation Safety Information Computational Center (RSICC) was established in 1963 to collect and disseminate computational nuclear technology in the form of radiation transport, shielding and safety software and corresponding nuclear cross sections. Approximately 1700 nuclear software and data packages are in the RSICC collection, and the majority are applicable to reactor dosimetry.

  12. Composite seals for liquid hydrogen and nuclear radiation environments.

    NASA Technical Reports Server (NTRS)

    Van Auken, R. L.; Chase, V. A.

    1971-01-01

    Description of plastic composite seals for service in a liquid-hydrogen and nuclear-radiation environment. The radiation-resistant aromatic heterocyclic class of polymers, including polyimide, polybenzimidazole, and polyquinoxaline, were evaluated for this application. The seal developed is based on a design involving a resin-starved laminate consisting of alternating layers of woven glass fabric and polymer film. This design imparts a mechanical spring characteristic to the seal, resulting in essentially complete elastic recovery when unloaded, and eliminates cold flow. Encapsulating techniques employing the polyquinoxaline polymer were developed which rendered the seal impervious to liquid hydrogen. The seals were tested before and after gamma irradiation up to 10 to the 10th ergs/g. Load/deflection and leakage tests were performed over a temperature range from -423 through +500 F.

  13. Nuclear fragmentation measurements for hadrontherapy and space radiation protection

    SciTech Connect

    De Napoli, M.; Agodi, C.; Blancato, A. A.; Cavallaro, M.; Cirrone, G. A. P.; Cuttone, G.; Sardina, D.; Scuderi, V.; Battistoni, G.; Bondi, M.; Cappuzzello, F.; Carbone, D.; Nicolosi, D.; Raciti, G.; Tropea, S.; Giacoppo, F.; Morone, M. C.; Pandola, L.; Rapisarda, E.; Romano, F.; and others

    2013-04-19

    Nuclear fragmentation measurements are necessary in hadrontherapy and space radiation protection, to predict the effects of the ion nuclear interactions within the human body. Nowadays, a very limited set of carbon fragmentation cross sections has been measured and in particular, to our knowledge, no double differential fragmentation cross sections at intermediate energies are available in literature. We have measured the double differential cross sections and the angular distributions of the secondary fragments produced in the {sup 12}C fragmentation at 62 AMeV on a thin carbon target. The experimental data have been also used to benchmark the prediction capability of the Geant4 Monte Carlo code at intermediate energies, where it was never tested before.

  14. Radiation doses to staff in a department of nuclear medicine.

    PubMed

    Harbottle, E A; Parker, R P; Davis, R

    1976-07-01

    A survey of data concerning radiation protection of staff working in the Nuclear Medicine Department and associated sections of the Physics Department at the Royal Marsden Hospital (Surrey Branch) is given for the period 1972 to 1975 inclusive. Results of routine film monitoring and whole-body counting are presented. Additional film monitors were used to check working areas, finger doses and any discrepancies between doses to the upper and lower trunk of personnel. In general, exposure to staff in the Nuclear Medicine Department is below 220 mrad per person per year, and below 1,000 mrad per person per year in the Radioisotope Dispensary. The dose received by radiographers is primarily due to spending time close to patients. Since about 5,000 intravenous injections of radionuclides are given each year in our department, the resulting finger doses to the staff involved may give rise to concern unless the task is shared. PMID:824004

  15. Nuclear data needed for applications in radiation oncology

    SciTech Connect

    White, R.M.; Chadwick, M.B.; Siantar, C.L.H.; Chandler, W.P.

    1994-03-01

    Fast neutrons have been used to treat over 15,000 cancer patients in approximately twenty centers worldwide and proton therapy is emerging as a potential treatment of choice for tumors near critical anatomical structures. Neutron therapy requires reaction data to {approximately}70 MeV while proton therapy requires data to {approximately}250 MeV. The cross section databases require energy- and angle-dependent cross sections for secondary neutrons, charged-particles and recoil nuclei. We discuss expansion of our nuclear databases and development of a three-dimensional radiation transport package that uses CT images as the input mesh to an all-particle Monte Carlo code. Called PEREGRINE, this code calculates dose distributions in the human body and can be used as a tool to determine the dependence of dose on details of the evaluated nuclear data.

  16. Circuit design for nuclear radiation test of CMOS multiplier chips

    SciTech Connect

    Lim, T.S.; Martin, R.L.; Hughes, H.L.

    1986-09-01

    This paper describes the design of a microprocessor-based electronic circuit to be used in testing the effects of nuclear radiation on a CMOS 8 x 8 multiplier chip. Knowledge of such effects is important for military and space applications of integrated circuits. The multiplier chip undergoing testing is attached to a DUT (device under test) board which is enclosed in a metal container. The container is then lowered to the cobalt 60 radiation source located at the bottom of a 15-ft-deep pool. The gamma-ray radiation test setup is schematically shown. The in-source test board containing the multiplier chip is attached to an 8085-based, single-board microcomputer (SDK-85) by a 30-ft multiconductor cable. Doses of gamma-ray radiation from cobalt 60 are applied in steps at increasing quantities until the multiplier chip, which is tested between doses, begins to malfunction. An 8085 assembly language program is used for functional test of the multiplier. The leakage current and the propagation delay time are also measured between doses.

  17. Yang-Mills radiation in ultrarelativistic nuclear collisions

    NASA Astrophysics Data System (ADS)

    Gyulassy, M.; McLerran, L.

    1997-10-01

    The classical Yang-Mills radiation computed in the McLerran-Venugopalan model is shown to be equivalent to the gluon bremsstrahlung distribution to lowest (g6) order in pQCD. The classical distribution is also shown to match smoothly onto the conventional pQCD minijet distribution at a scale k2⊥~χ, characteristic of the initial parton transverse density of the system. The atomic number and energy dependence of χ is computed from available structure function information. The limits of applicability of the classical Yang-Mills description of nuclear collisions at RHIC and LHC energies are discussed.

  18. Cancer near the Three Mile Island nuclear plant: radiation emissions.

    PubMed

    Hatch, M C; Beyea, J; Nieves, J W; Susser, M

    1990-09-01

    As a public charge, cancers among the 159,684 residents living within a 10-mile (16-km) radius of the Three Mile Island nuclear plant were studied relative to releases of radiation during the March 28, 1979, accident as well as to routine plant emissions. The principal cancers considered were leukemia and childhood malignancies. Estimates of the emissions delivered to small geographic study tracts were derived from mathematical dispersion models which accounted for modifying factors such as wind and terrain; the model of accident emissions was validated by readings from off-site dosimeters. Incident cancers among area residents for the period 1975-1985 (n = 5,493) were identified by a review of the records at all local and regional hospitals; preaccident and postaccident trends in cancer rates were examined. For accident emissions, the authors failed to find definite effects of exposure on the cancer types and population subgroups thought to be most susceptible to radiation. No associations were seen for leukemia in adults or for childhood cancers as a group. For leukemia in children, the odds ratio was raised, but cases were few (n = 4), and the estimate was highly variable. Moreover, rates of childhood leukemia in the Three Mile Island area are low compared with national and regional rates. For exposure to routine emissions, the odds ratios were raised for childhood cancers as a whole and for childhood leukemia, but confidence intervals were wide and included 1.0. For leukemia in adults, there was a negative trend. Trends for two types of cancer ran counter to expectation. Non-Hodgkin's lymphoma showed raised risks relative to both accident and routine emissions; lung cancer (adjusted only indirectly for smoking) showed raised risks relative to accident emissions, routine emissions, and background gamma radiation. Overall, the pattern of results does not provide convincing evidence that radiation releases from the Three Mile Island nuclear facility influenced

  19. New Versions of Terahertz Radiation Sources for Dynamic Nuclear Polarization in Nuclear Magnetic Resonance Spectroscopy

    NASA Astrophysics Data System (ADS)

    Bratman, V. L.; Kalynov, Yu. K.; Makhalov, P. B.; Fedotov, A. E.

    2014-01-01

    Dynamic nuclear polarization in strong-field nuclear magnetic resonance (NMR) spectroscopy requires terahertz radiation with moderate power levels. Nowadays, conventional gyrotrons are used almost exclusively to generate such radiation. In this review paper, we consider alternative variants of electronic microwave oscillators which require much weaker magnetic fields for their operation, namely, large-orbit gyrotrons operated at high cyclotron-frequency harmonics and Čerenkov-type devices, such as a backward-wave oscillator and a klystron frequency multiplier with tubular electron beams. Additionally, we consider the possibility to use the magnetic field created directly by the solenoid of an NMR spectrometer for operation of both the gyrotron and the backward-wave oscillator. Location of the oscillator in the spectrometer magnet makes it superfluous to use an additional superconducting magnet creating a strong field, significantly reduces the length of the radiation transmission line, and, in the case of Čerenkov-type devices, allows one to increase considerably the output-signal power. According to our calculations, all the electronic devices considered are capable of ensuring the power required for dynamic nuclear polarization (10 W or more) at a frequency of 260 GHz, whereas the gyrotrons, including their versions proposed in this paper, remain a single option at higher frequencies.

  20. Radiation dose study in nuclear medicine using GATE

    NASA Astrophysics Data System (ADS)

    Aguwa, Kasarachi

    Dose as a result of radiation exposure is the notion generally used to disclose the imparted energy in a volume of tissue to a potential biological effect. The basic unit defined by the international system of units (SI system) is the radiation absorbed dose, which is expressed as the mean imparted energy in a mass element of the tissue known as "gray" (Gy) or J/kg. The procedure for ascertaining the absorbed dose is complicated since it involves the radiation transport of numerous types of charged particles and coupled photon interactions. The most precise method is to perform a full 3D Monte Carlo simulation of the radiation transport. There are various Monte Carlo toolkits that have tool compartments for dose calculations and measurements. The dose studies in this thesis were performed using the GEANT4 Application for Emission Tomography (GATE) software (Jan et al., 2011) GATE simulation toolkit has been used extensively in the medical imaging community, due to the fact that it uses the full capabilities of GEANT4. It also utilizes an easy to-learn GATE macro language, which is more accessible than learning the GEANT4/C++ programming language. This work combines GATE with digital phantoms generated using the NCAT (NURBS-based cardiac-torso phantom) toolkit (Segars et al., 2004) to allow efficient and effective estimation of 3D radiation dose maps. The GATE simulation tool has developed into a beneficial tool for Monte Carlo simulations involving both radiotherapy and imaging experiments. This work will present an overview of absorbed dose of common radionuclides used in nuclear medicine and serve as a guide to a user who is setting up a GATE simulation for a PET and SPECT study.

  1. Impact of phonon coupling on the radiative nuclear reaction characteristics

    NASA Astrophysics Data System (ADS)

    Achakovskiy, Oleg; Avdeenkov, Alexander; Kamerdzhiev, Sergei

    2016-01-01

    The pygmy dipole resonance and photon strength functions (PSF) in stable and unstable Ni and Sn isotopes are calculated within the microscopic self-consistent version of the extended theory of finite Fermi systems in the quasiparticle time blocking approximation. The approach includes phonon coupling (PC) effects in addition to the standard QRPA approach. The Skyrme force SLy4 is used. A pygmy dipole resonance in 72Ni is predicted at the mean energy of 12.4 MeV exhausting 25.7% of the total energy-weighted sum rule. With our microscopic E1 PSFs in the EMPIRE 3.1 code, the following radiative nuclear reaction characteristics have been calculated for several stable and unstable even-even Sn and Ni isotopes: 1) neutron capture cross sections, 2) corresponding neutron capture gamma-spectra, 3) average radiative widths of neutron resonances. Here, three variants of the microscopic nuclear level density models have been used and a comparison with the phenomenological generalized superfluid model has been performed. In all the considered properties, including the recent experimental data for PSF in Sn isotopes, the PC contributions turned out to be significant, as compared with the QRPA one, and necessary to explain the available experimental data.

  2. The Radiation Safety Information Computational Center (RSICC): A Resource for Nuclear Science Applications

    SciTech Connect

    Kirk, Bernadette Lugue

    2009-01-01

    The Radiation Safety Information Computational Center (RSICC) has been in existence since 1963. RSICC collects, organizes, evaluates and disseminates technical information (software and nuclear data) involving the transport of neutral and charged particle radiation, and shielding and protection from the radiation associated with: nuclear weapons and materials, fission and fusion reactors, outer space, accelerators, medical facilities, and nuclear waste management. RSICC serves over 12,000 scientists and engineers from about 100 countries.

  3. IEEE Nuclear and Space Radiation Effects Conference: Notes on the Early Conferences

    NASA Technical Reports Server (NTRS)

    Pellish, Jonathan A.; Galloway, Kenneth F.

    2013-01-01

    This paper gathers the remembrances of several key contributors who participated in the earliest Institute of Electrical and Electronics Engineers (IEEE) Nuclear and Space Radiation Effects Conferences (NSREC).

  4. Radiation and Thermal Stability of Murataite Ceramics Nuclear Waste Forms

    NASA Astrophysics Data System (ADS)

    Lian, J.; Yudintsev, S. V.; Stefanovsky, S. V.

    2006-05-01

    The wide range of complex nuclear wastes requires a variety of robust hosts for long-term storage during disposal. Wastes with high actinide and iron concentrations have generated intense interest in murataite ceramics as a candidate waste form due to its four distinct cation sites as well as cation vacancies. Critical to this application is the radiation stability of the waste host. We have determined both the radiation and thermal stabilities of murataite ceramics using in situ observations in a transmission electron microscope during ion bombardment at the Electron Microscopy Center at Argonne National Laboratory. A central issue for structural stability is radiation damage-induced crystalline-to-amorphous transformation that may result in macroscopic swelling, cracking and phase decomposition. Such a response would lead to a significant change in chemical durability and release of incorporated radionuclides. We found that, murataite ceramics are susceptible to ion beam induce ordered-disordered transition and amorphization. The ion dose required for amorphization was determined as a function of temperature and the degree of initial structural disorder. The upper temperature limit for amorphization of murataites was determined to be in the range of 860 K to 1060 K for 1 MeV Kr2+ ion irradiation. Decrease of the susceptibility to irradiation induced amorphization for disordered murataite, suggests that the amorphization susceptibility depends, in part, on the initial degree of intrinsic disorder prior to irradiation. The thermal stability of murataite polytypes was studied by in-situ TEM observation. Phase decomposition with the precipitation of Fe-rich nanocrystals was induced in the murataite structure. The phase decomposition and nanocrystal formation have no significant effects on the radiation resistance of murataite ceramics used as potential host phases for the immobilization of actinides.

  5. System for determining the type of nuclear radiation from detector output pulse shape

    DOEpatents

    Miller, W.H.; Berliner, R.R.

    1994-09-13

    A radiation detection system determines the type of nuclear radiation received in a detector by producing a correlation value representative of the statistical cross correlation between the shape of the detector signal and pulse shape data previously stored in memory and characteristic of respective types of radiation. The correlation value is indicative of the type of radiation. The energy of the radiation is determined from the detector signal and is used to produce a spectrum of radiation energies according to radiation type for indicating the nature of the material producing the radiation. 2 figs.

  6. System for determining the type of nuclear radiation from detector output pulse shape

    DOEpatents

    Miller, William H.; Berliner, Ronald R.

    1994-01-01

    A radiation detection system determines the type of nuclear radiation received in a detector by producing a correlation value representative of the statistical cross correlation between the shape of the detector signal and pulse shape data previously stored in memory and characteristic of respective types of radiation. The correlation value is indicative of the type of radiation. The energy of the radiation is determined from the detector signal and is used to produce a spectrum of radiation energies according to radiation type for indicating the nature of the material producing the radiation.

  7. Overcoming the specific power limitations of nuclear electric propulsion by laser radiators

    NASA Astrophysics Data System (ADS)

    Winterberg, F.

    1997-07-01

    It is shown that the specific power of nuclear electric propulsion can be greatly increased by replacing black body radiators with laser radiators. In black body radiators the atomic oscillators have a random phase with the emission rate for black body radiators proportional to the sum of the squared amplitudes. In laser radiators the oscillators are all in phase with the emission rate proportional to the squared sum of the amplitudes, which is the reason for the much larger emission rate of laser radiators. In a laser radiator the low entropy low temperature laser beam removes the waste heat by resonance absorption and isotropic reemission of the laser radiation into space.

  8. Evaluation of gamma radiation shielding for nuclear waste shipping casks

    SciTech Connect

    Liu, Y.Y.; Carlson, R.D.; Primeau, S.J.; Wangler, M.E.

    1998-05-01

    A method has been developed for evaluating gamma radiation shielding of shipping casks that are used to transport nuclear waste with ill-defined radionuclide contents. The method is based on calculations that establish individual limits for a comprehensive list of radionuclides in the waste, assuming that each radionuclide is uniformly distributed in a volumetric source in the cask. For multiple radionuclide mixtures, a linear fraction rule is used to restrict the total amount of radionuclides such that the sum of the fractions does not exceed 1. As long as the radionuclide limits and the linear fraction rule are followed, it can be shown that the regulatory dose rate requirements for a cask will be satisfied under normal conditions of transport and in a hypothetical accident during which the shielding thickness of the cask has been reduced by 40%.

  9. Electromagnetic radiation from nuclear collisions at ultrarelativistic energies

    NASA Astrophysics Data System (ADS)

    Turbide, Simon; Gale, Charles; Frodermann, Evan; Heinz, Ulrich

    2008-02-01

    The hot and dense strongly interacting matter created in collisions of heavy nuclei at RHIC energies is modeled with relativistic hydrodynamics, and the spectra of real and virtual photons produced at midrapidity in these events are calculated. Several different sources are considered, and their relative importance is compared. Specifically, we include jet fragmentation, jet-plasma interactions, the emission of radiation from the thermal medium and from primordial hard collisions. Our calculations consistently take into account jet energy loss, as evaluated in the AMY formalism. We obtain results for the spectra, the nuclear modification factor (RAAγ), and the azimuthal anisotropy (v2γ) that agree with the photon measurements performed by the PHENIX Collaboration at RHIC.

  10. Special Radiation Protection Precautions in Therapeutic Nuclear Medicine

    NASA Astrophysics Data System (ADS)

    Stefanoyiannis, A. P.; Gerogiannis, J.

    2010-01-01

    Therapeutic Nuclear Medicine concerns the administration of appropriate amounts of radioactivity of certain isotopes, in order to achieve internal localized irradiation of neoplasmatic cells. Due to the increased level and the specific isotope characteristics of administered radioactivity, special Radiation Protection precautions must be taken. This study addresses such issues, based on national as well as international legislation and guidelines. Application of the principle of optimization is of outmost importance and is based on individual dose planning. The decision about the release of Nuclear Medicine patients after therapy is determined on an individual basis, taking into account patients' pattern of contact with other people, their age and that of persons in the home environment, in addition to other factors. Estimation of the absorbed dose given to the treated organ is based on uptake measurements and other biokinetic data, as well as on the mass of the treated tissue or organ. Concerning pregnant women, the rule of thumb is that they should not be treated, unless the radionuclide therapy is required to save their lives. In that case, the potential absorbed dose and risk to the foetus should be estimated and conveyed to the patient. After radionuclide therapy, a female should be advised to avoid pregnancy for the period of time depending on the specific radionuclide. This is to ensure that the dose to a conceptus/foetus would probably not exceed 1 mGy (the member of the public dose limit). The radiation risk for relatives and caregivers is small and unlikely to exceed the legal dose constraints during the period of the patient's treatment. Solid waste from the patient's stay in hospital is a different matter, and is normally incinerated or held for a period until radioactive decay brings the activity to an acceptable level.

  11. Improved spectrometric characteristics of thallium bromide nuclear radiation detectors

    NASA Astrophysics Data System (ADS)

    Hitomi, K.; Murayama, T.; Shoji, T.; Suehiro, T.; Hiratate, Y.

    1999-06-01

    Thallium bromide (TlBr) is a compound semiconductor with a high atomic number and wide band gap. In this study, nuclear radiation detectors have been fabricated from the TlBr crystals. The TlBr crystals were grown by the horizontal travelling molten zone (TMZ) method using the materials purified by many pass zone refining. The crystals were characterized by measuring the resistivity, the mobility-lifetime ( μτ) product and the energy required to create an electron-hole pair (the ɛ value). Improved energy resolution has been obtained by the TlBr radiation detectors. At room temperature the full-width at half-maximum (FWHM) for the 59.5, 122 and 662 keV γ-ray photo peak obtained from the detectors were 3.3, 8.8 and 29.5 keV, respectively. By comparing the saturated peak position of the TlBr detector with that of the CdTe detector, the ɛ value has been estimated to be about 5.85 eV for the TlBr crystal.

  12. Importance of Bladder Radioactivity for Radiation Safety in Nuclear Medicine

    PubMed Central

    Gültekin, Salih Sinan; Şahmaran, Turan

    2013-01-01

    Objective: Most of the radiopharmaceuticals used in nuclear medicine are excreted via the urinary system. This study evaluated the importance of a reduction in bladder radioactivity for radiation safety. Methods: The study group of 135 patients underwent several organ scintigraphies [40/135; thyroid scintigraphy (TS), 30/135; whole body bone scintigraphy (WBS), 35/135; myocardial perfusion scintigraphy (MPS) and 30/135; renal scintigraphy (RS)] by a technologist within 1 month. In full and empty conditions, static bladder images and external dose rate measurements at 0.25, 0.50, 1, 1.5 and 2 m distances were obtained and decline ratios were calculated from these two data sets. Results: External radiation dose rates were highest in patients undergoing MPS. External dose rates at 0.25 m distance for TS, TKS, MPS and BS were measured to be 56, 106, 191 and 72 μSv h-1 for full bladder and 29, 55, 103 and 37 μSv h-1 for empty bladder, respectively. For TS, WBS, MPS and RS, respectively, average decline ratios were calculated to be 52%, 55%, 53% and 54% in the scintigraphic assessment and 49%, 51%, 49%, 50% and 50% in the assessment with Geiger counter. Conclusion: Decline in bladder radioactivity is important in terms of radiation safety. Patients should be encouraged for micturition after each scintigraphic test. Spending time together with radioactive patients at distances less than 1 m should be kept to a minimum where possible. Conflict of interest:None declared. PMID:24416625

  13. Thermal and dynamic analysis of the RING (Radiatively-cooled, Inertially-driven Nuclear Generator) power system radiator

    SciTech Connect

    Apley, W.J.; Babb, A.L.

    1989-01-01

    The nuclear option for a space-based power system appears most suitable for missions that require long-term, sustained operation at power levels above 100 kWe. Systems currently available operate at relatively low thermal efficiencies (6--10%). Thus, a 100 kWe system must discharge nearly 2 MWth of waste heat through the comparatively inefficient process of radiative cooling. The impact of the resultant radiator assembly size on overall power system weight is significant, and has led to proposals for radiators with potentially higher efficiencies. Examples include the: liquid droplet radiator; fabric radiator; bubble membrane radiator; rotating film radiator; and dust radiator. 14 refs., 2 figs., 2 tabs.

  14. 48 CFR 952.223-72 - Radiation protection and nuclear criticality.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... nuclear criticality. 952.223-72 Section 952.223-72 Federal Acquisition Regulations System DEPARTMENT OF....223-72 Radiation protection and nuclear criticality. As prescribed in 923.7003 the clause set forth... contract or subcontract rather than by reliance upon Nuclear Regulatory Commission licensing...

  15. 48 CFR 952.223-72 - Radiation protection and nuclear criticality.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... nuclear criticality. 952.223-72 Section 952.223-72 Federal Acquisition Regulations System DEPARTMENT OF....223-72 Radiation protection and nuclear criticality. As prescribed in 923.7003 the clause set forth... contract or subcontract rather than by reliance upon Nuclear Regulatory Commission licensing...

  16. Radiation damage microstructures in nuclear ceramics with applications in fusion energy technology and nuclear waste disposal

    SciTech Connect

    Hobbs, L.W.

    1989-09-01

    This final technical report documents the accomplishments of the program of research entitled Radiation Damage Microstructures in Nuclear Ceramics'' funded between July 1984 and July 1988 under DOE Grant FG02-84ER45090. The initial program, begun at MIT in 1983, had as its objective investigation of the radiation responses of ceramics, heavily-irradiated with electrons, neutrons and ions, with potential applications to fusion energy technology and high-level nuclear waste storage. Materials investigated included SiO{sub 2}, MgAl{sub 2}O{sub 4}, Al{sub 23}O{sub 27}N{sub 5}, SiC, BeO, LiAlO{sub 2}, Li{sub 2}ZrO{sub 3}, CaTiO{sub 3}, KTaO{sub 3} and Ca(Zr,Pu)Ti{sub 2}O{sub 7}. The issues involved have been the subject of a series of DOE-sponsored workshops in which the principal investigator has prominently participated, as well as of two informal collaborative meetings among DOE-supported groups at MIT, Los Alamos, University of New Mexico, Boeing, Oak Ridge National Laboratory and Battelle-Pacific Northwest Laboratory.

  17. Nuclear Radiation Tolerance of Single Crystal Aluminum Nitride Ultrasonic Transducer

    NASA Astrophysics Data System (ADS)

    Reinhard, Brian; Tittmann, Bernhard R.; Suprock, Andrew

    Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models, (Rempe et al., 2011; Kazys et al., 2005). These efforts are limited by the lack of identified ultrasonic transducer materials capable of long term performance under irradiation test conditions. To address this need, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate the performance of promising magnetostrictive and piezoelectric transducers in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2. The irradiation is also supported by a multi-National Laboratory collaboration funded by the Nuclear Energy Enabling Technologies Advanced Sensors and Instrumentation (NEET ASI) program. The results from this irradiation, which started in February 2014, offer the potential to enable the development of novel radiation tolerant ultrasonic sensors for use in Material Testing Reactors (MTRs). As such, this test is an instrumented lead test and real-time transducer performance data is collected along with temperature and neutron and gamma flux data. Hence, results from this irradiation offer the potential to bridge the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the

  18. Technical Basis Spent Nuclear Fuel (SNF) Project Radiation and Contamination Trending Program

    SciTech Connect

    KURTZ, J.E.

    2000-05-10

    This report documents the technical basis for the Spent Nuclear Fuel (SNF) Program radiation and contamination trending program. The program consists of standardized radiation and contamination surveys of the KE Basin, radiation surveys of the KW basin, and radiation surveys of the Cold Vacuum Drying Facility (CVD) with the associated tracking. This report also discusses the remainder of radiological areas within the SNFP that do not have standardized trending programs and the basis for not having this program in those areas.

  19. Modern new nuclear fuel characteristics and radiation protection aspects.

    PubMed

    Terry, Ian R

    2005-01-01

    The glut of fissile material from reprocessing plants and from the conclusion of the cold war has provided the opportunity to design new fuel types to beneficially dispose of such stocks by generating useful power. Thus, in addition to the normal reactor core complement of enriched uranium fuel assemblies, two other types are available on the world market. These are the ERU (enriched recycled uranium) and the MOX (mixed oxide) fuel assemblies. Framatome ANP produces ERU fuel assemblies by taking feed material from reprocessing facilities and blending this with highly enriched uranium from other sources. MOX fuel assemblies contain plutonium isotopes, thus exploiting the higher neutron yield of the plutonium fission process. This paper describes and evaluates the gamma, spontaneous and alpha reaction neutron source terms of these non-irradiated fuel assembly types by defining their nuclear characteristics. The dose rates which arise from these terms are provided along with an overview of radiation protection aspects for consideration in transporting and delivering such fuel assemblies to power generating utilities. PMID:16381693

  20. Determine Important Nuclear Fragmentation Processes for Space Radiation Protection in Human Space Explorations

    NASA Technical Reports Server (NTRS)

    Lin, Zi-Wei

    2004-01-01

    Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most affect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space explorations.

  1. Determine Important Nuclear Fragmentation Processes for Space Radiation Protection in Human Space Explorations

    NASA Technical Reports Server (NTRS)

    Lin, Zi-wei

    2004-01-01

    Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most effect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space explorations.

  2. Determine Important Nuclear Fragmentation Processes for Space Radiation Protection in Human Space Explorations

    NASA Technical Reports Server (NTRS)

    Lin, Zi-Wei

    2004-01-01

    Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most affect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space exploration.

  3. Nuclear-Pumped Lasers. [efficient conversion of energy liberated in nuclear reactions to coherent radiation

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The state of the art in nuclear pumped lasers is reviewed. Nuclear pumped laser modeling, nuclear volume and foil excitation of laser plasmas, proton beam simulations, nuclear flashlamp excitation, and reactor laser systems studies are covered.

  4. Nuclear Decay Data in the MIRD (Medical Internal Radiation Dose) Format

    DOE Data Explorer

    MIRD is a database of evaluated nuclear decay data for over 2,100 radioactive nuclei. Data are extracted from ENSDF, processed by the program RadList, and used for medical internal radiation dose calculations. When using the MIRD interface, tables of nuclear and atomic radiations from nuclear decay and decay scheme drawings will be produced in the MIRD format from the Evaluated Nuclear Structure Data File (ENSDF) for the specified nuclide. Output may be either HTML-formatted tables and JPEG drawings, PostScript tables and drawings, or PDF tables and drawings.

  5. 1987 Annual Conference on Nuclear and Space Radiation Effects, Snowmass Village, CO, July 28-31, 1987, Proceedings

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Various papers on nuclear and space radiation effects are presented. The general topics addressed include: basic mechanisms of radiation effects, single-event phenomena, temperature and field effects, modeling and characterization of radiation effects, IC radiation effects and hardening, and EMP/SGEMP/IEMP phenomena. Also considered are: dosimetry/energy-dependent effects, sensors in and for radiation environments, spacecraft charging and space radiation effects, radiation effects and devices, radiation effects on isolation technologies, and hardness assurance and testing techniques.

  6. Radiation damage studies related to nuclear waste forms

    SciTech Connect

    Gray, W.J.; Wald, J.W.; Turcotte, R.P.

    1981-12-01

    Much of the previously reported work on alpha radiation effects on crystalline phases of importance to nuclear waste forms has been derived from radiation effects studies of composite waste forms. In the present work, two single-phase crystalline materials, Gd/sub 2/Ti/sub 2/O/sub 7/ (pyrochlore) and CaZrTi/sub 2/O/sub 7/ (zirconolite), of relative importance to current waste forms were studied independently by doping with /sup 244/Cm at the 3 wt % level. Changes in the crystalline structure measured by x-ray diffraction as a function of dose show that damage ingrowth follows an expected exponential relationship of the form ..delta..V/V/sub 0/ = A(1-exp(-BD)). In both cases, the materials became x-ray amorphous before the estimated saturation value was reached. The predicted magnitudes of the unit cell volume changes at saturation are 5.4% and 3.5%, respectively, for Gd/sub 2/Ti/sub 2/O/sub 7/ and CaZrTi/sub 2/O/sub 7/. The later material exhibited anisotropic behavior in which the expansion of the monoclinic cell in the c/sub 0/ direction was over five times that of the a/sub 0/ direction. The effects of transmutations on the properties of high-level waste solids have not been studied until now because of the long half-lives of the important fission products. This problem was circumvented in the present study by preparing materials containing natural cesium and then irradiating them with neutrons to produce /sup 134/Cs, which has only a 2y half-life. The properties monitored at about one year intervals following irradiation have been density, leach rate and microstructure. A small amount of x-ray diffraction work has also been done. Small changes in density and leach rate have been observed for some of the materials, but they were not large enough to be of any consequence for the final disposal of high level wastes.

  7. Remembering Fukushima: PNNL Monitors Radiation from Nuclear Disaster

    ScienceCinema

    Miley, Harry

    2014-06-12

    Senior Scientist Harry Miley describes how his work in ultra-trace, nuclear detection technology picked up the first reading of radiological materials over the U.S. following the nuclear power plant explosion in Japan.

  8. Remembering Fukushima: PNNL Monitors Radiation from Nuclear Disaster

    SciTech Connect

    Miley, Harry

    2014-03-07

    Senior Scientist Harry Miley describes how his work in ultra-trace, nuclear detection technology picked up the first reading of radiological materials over the U.S. following the nuclear power plant explosion in Japan.

  9. Delayed gamma radiation from lightning induced nuclear reactions

    NASA Astrophysics Data System (ADS)

    Greenfield, M. B.; Sakuma, K.; Ikeda, Y.; Kubo, K.

    2004-03-01

    An increase in atmospheric gamma radiation observed with NaI and Ge detectors positioned about 15 m above ground was observed following natural lightning near Tokyo, Japan [1]. Background subtracted gamma ray rates GRR following numerous lightning strokes observed since 2001 persisted for a few hours and subsequently decayed with a half-life of about 50 minutes. Using a 3x3 Ge detector, with 2 KeV resolution, positioned about 2 m from one of the NaI detectors increases in GRR were observed minutes after the onset of lightning with a delayed 50 min exponential decay. Although most of the increase in activity occured at less than a few 100 KeV, on July 11, 2003 a 1267 +/-2 KeV line was observed. Although the statistics of this event were poor, the appearance of this line with an exponential decay of 50 min half-life suggests the possibility that it may be due to 39Cl (1267 MeV; half-life = 55.5 min) via the 40Ar(gamma,p)39Cl, 40Ar(p,2p)39Cl and/or 40Ar(n,d)39Cl reactions. Observations of > 10 MeV gamma rays observed in NaI detectors within 10s of meters from and coincident with rocket-triggered lightning at the International Center for Lightning Research and Testing suggest that charged particles accelerated in intense electric fields associated with lightning give rise to photons with sufficient energy to initiate nuclear reactions [2]. Further work to explain the cause of this anomalous activity is underway using natural and triggered lightning. 1. M. B. Greenfield et al., Journal of Applied Physics 93 no. 3 (2003) pp 1839-184. 2. J. R. Dwyer et al., Science 299, (2003), pp 694-697 and recent communications

  10. Monitoring of radiation dose rates around a clinical nuclear medicine site

    NASA Astrophysics Data System (ADS)

    Shao, Chia-Ho; Lu, Cheng-Chang; Chen, Tou-Rong; Weng, Jui-Hung; Kao, Pan-Fu; Dong, Shang-Lung; Chou, Ming-Jen

    2014-11-01

    The monitoring of radiation dose around the nuclear medicine site is an important study issue. In this study, TLD-100H radiation dosimeters were used to measure the ambient radiation dose rates around a clinical nuclear medicine site in order to investigate the latent hot zones of radiation exposure. Results of this study showed that the radiation doses measured from all piping and storage systems were comparable to the background dose. A relatively high dose was observed at the single bend point of waste water piping of the PET/CT. Another important finding was the unexpected high dose rates observed at the non-restricted waiting area (NRWA) of SPECT. To conclude, this study provides useful information for further determination of an appropriate dose reduction strategy to achieve the ALARA principle in a clinical nuclear medicine site.

  11. Radiation Injury After a Nuclear Detonation: Medical Consequences and the Need for Scarce Resources Allocation

    PubMed Central

    DiCarlo, Andrea L.; Maher, Carmen; Hick, John L.; Hanfling, Dan; Dainiak, Nicholas; Chao, Nelson; Bader, Judith L.; Coleman, C. Norman; Weinstock, David M.

    2013-01-01

    A 10-kiloton (kT) nuclear detonation within a US city could expose hundreds of thousands of people to radiation. The Scarce Resources for a Nuclear Detonation Project was undertaken to guide community planning and response in the aftermath of a nuclear detonation, when demand will greatly exceed available resources. This article reviews the pertinent literature on radiation injuries from human exposures and animal models to provide a foundation for the triage and management approaches outlined in this special issue. Whole-body doses >2 Gy can produce clinically significant acute radiation syndrome (ARS), which classically involves the hematologic, gastrointestinal, cutaneous, and cardiovascular/central nervous systems. The severity and presentation of ARS are affected by several factors, including radiation dose and dose rate, interindividual variability in radiation response, type of radiation (eg, gamma alone, gamma plus neutrons), partial-body shielding, and possibly age, sex, and certain preexisting medical conditions. The combination of radiation with trauma, burns, or both (ie, combined injury) confers a worse prognosis than the same dose of radiation alone. Supportive care measures, including fluid support, antibiotics, and possibly myeloid cytokines (eg, granulocyte colony-stimulating factor), can improve the prognosis for some irradiated casualties. Finally, expert guidance and surge capacity for casualties with ARS are available from the Radiation Emergency Medical Management Web site and the Radiation Injury Treatment Network. PMID:21402810

  12. Radiation injury after a nuclear detonation: medical consequences and the need for scarce resources allocation.

    PubMed

    DiCarlo, Andrea L; Maher, Carmen; Hick, John L; Hanfling, Dan; Dainiak, Nicholas; Chao, Nelson; Bader, Judith L; Coleman, C Norman; Weinstock, David M

    2011-03-01

    A 10-kiloton (kT) nuclear detonation within a US city could expose hundreds of thousands of people to radiation. The Scarce Resources for a Nuclear Detonation Project was undertaken to guide community planning and response in the aftermath of a nuclear detonation, when demand will greatly exceed available resources. This article reviews the pertinent literature on radiation injuries from human exposures and animal models to provide a foundation for the triage and management approaches outlined in this special issue. Whole-body doses >2 Gy can produce clinically significant acute radiation syndrome (ARS), which classically involves the hematologic, gastrointestinal, cutaneous, and cardiovascular/central nervous systems. The severity and presentation of ARS are affected by several factors, including radiation dose and dose rate, interindividual variability in radiation response, type of radiation (eg, gamma alone, gamma plus neutrons), partial-body shielding, and possibly age, sex, and certain preexisting medical conditions. The combination of radiation with trauma, burns, or both (ie, combined injury) confers a worse prognosis than the same dose of radiation alone. Supportive care measures, including fluid support, antibiotics, and possibly myeloid cytokines (eg, granulocyte colony-stimulating factor), can improve the prognosis for some irradiated casualties. Finally, expert guidance and surge capacity for casualties with ARS are available from the Radiation Emergency Medical Management Web site and the Radiation Injury Treatment Network. PMID:21402810

  13. Technical Basis Spent Nuclear Fuel (SNF) Project Radiation and Contamination Trending Program

    SciTech Connect

    ELGIN, J.C.

    2000-10-02

    This report documents the technical basis for the Spent Nuclear Fuel (SNF) Program radiation and contamination trending program. The program consists of standardized radiation and contamination surveys of the KE Basin, radiation surveys of the KW basin, radiation surveys of the Cold Vacuum Drying Facility (CVD), and radiation surveys of the Canister Storage Building (CSB) with the associated tracking. This report also discusses the remainder of radiological areas within the SNFP that do not have standardized trending programs and the basis for not having this program in those areas.

  14. [Radiation measures and trend after the Fukushima Daiichi Nuclear Power Plant accident].

    PubMed

    Okazaki, Ryuji

    2014-02-01

    The radioactive materials spread by the Fukushima Daiichi Nuclear Power Plant (NPP) accident in March, 2011 caused NPP workers to be exposed to radiation above ordinance limits. The number of workers exposed to radiation within ordinance limits is increasing. Decontamination began at many places in Fukushima, although new laws were enforced in the decontamination work, in the current situation, medical examinations for radiation are limited due to a shortage of doctors. In this paper, I introduce the ordinances on the prevention of ionizing radiation hazards and the revised points about radiation exposure doses of the NPP workers, as well as the new ordinance for decontamination. PMID:24605520

  15. A Radiological Assessment Skills Training Program for the Radiation Worker at Shoreham Nuclear Power Station.

    ERIC Educational Resources Information Center

    Engel, Leonard, Jr.

    Radiation workers, by law, have the responsibility to maintain their exposure to radiation levels as low as possible. This responsibility has not been accepted. Instead, they have relied solely on the policing action of health physics (HP) technicians, thereby delegating their lawful responsibility. Continued overexposure in the U.S. nuclear power…

  16. Nuclear Technology Series. Radiation Protection Technician. A Suggested Program Planning Guide. Revised June 80.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This program planning guide for a two-year postsecondary radiation protection technician program is designed for use with courses 17-22 of thirty-five included in the Nuclear Technology Series. The purpose of the guide is to describe the nuclear power field and its job categories for specialists, technicians, and operators; and to assist planners,…

  17. Synthesis of calculational methods for design and analysis of radiation shields for nuclear rocket systems

    NASA Technical Reports Server (NTRS)

    Capo, M. A.; Disney, R. K.; Jordan, T. A.; Soltesz, R. G.; Woodsum, H. C.

    1969-01-01

    Eight computer programs make up a nine volume synthesis containing two design methods for nuclear rocket radiation shields. The first design method is appropriate for parametric and preliminary studies, while the second accomplishes the verification of a final nuclear rocket reactor design.

  18. Environmental radiation real-time monitoring system permanently installed near Qinshan Nuclear Power Plant.

    PubMed

    Ding, M; Sheng, P; Zhi, Z

    1996-03-01

    An environmental radiation real-time monitoring system with high pressure ionization chamber was developed. It has been installed permanently in the vicinity of Qinshan Nuclear Power Plant, the first built in mainland China. The system consists of four basic components: environmental radiation monitors; data communication network; a data processing center; and a remote terminal computer situated in Hangzhou. It has provided five million readings of environmental radiation levels as of January 1993. PMID:8609035

  19. An intermetallic forming steel under radiation for nuclear applications

    NASA Astrophysics Data System (ADS)

    Hofer, C.; Stergar, E.; Maloy, S. A.; Wang, Y. Q.; Hosemann, P.

    2015-03-01

    In this work we investigated the formation and stability of intermetallics formed in a maraging steel PH 13-8 Mo under proton radiation up to 2 dpa utilizing nanoindentation, microcompression testing and atom probe tomography. A comprehensive discussion analyzing the findings utilizing rate theory is introduced, comparing the aging process to radiation induced diffusion. New findings of radiation induced segregation of undersize solute atoms (Si) towards the precipitates are considered.

  20. Internal radiation therapy: a neglected aspect of nuclear medicine in the molecular era

    PubMed Central

    Lin, Yansong

    2015-01-01

    Abstract With increasing evidence, internal radiation therapy, also known as brachytherapy, has become a neglected aspect of nuclear medicine in the molecular era. In this paper, recent developments regarding internal radiation therapy, including developments in radioiodine-131 (131I) and thyroid, radioimmunotherapy (RIT) for non-Hodgkin lymphoma (NHL), and radiopharmaceuticals for bone metastases. Relevant differences and status of their applications in China were mentioned as well. These molecular mediated internal radiation therapies are gaining increasing importance by providing palliative and curative treatments for an increasing number of diseases and becoming one of the important parts of molecular nuclear medicine. PMID:26445567

  1. Nuclear medicine dose equivalent a method for determination of radiation risk

    SciTech Connect

    Huda, W.

    1986-12-01

    Conventional nuclear medicine dosimetry involves specifying individual organ doses. The difficulties that can arise with this approach to radiation dosimetry are discussed. An alternative scheme is described that is based on the ICRP effective dose equivalent, H/sub E/, and which is a direct estimate of the average radiation risk to the patient. The mean value of H/sub E/ for seven common /sup 99m/Tc nuclear medicine procedures is 0.46 rem and the average radiation risk from this level of exposure is estimated to be comparable to the risk from smoking approx. 28 packs of cigarettes or driving approx. 1300 miles.

  2. Tracking patient radiation exposure: challenges to integrating nuclear medicine with other modalities.

    PubMed

    Mercuri, Mathew; Rehani, Madan M; Einstein, Andrew J

    2012-10-01

    The cumulative radiation exposure to the patient from multiple radiological procedures can place some individuals at significantly increased risk for stochastic effects and tissue reactions. Approaches, such as those in the International Atomic Energy Agency's Smart Card program, have been developed to track cumulative radiation exposures to individuals. These strategies often rely on the availability of structured dose reports, typically found in the DICOM header. Dosimetry information is currently readily available for many individual x-ray-based procedures. Nuclear medicine, of which nuclear cardiology constitutes the majority of the radiation burden in the US, currently lags behind x-ray-based procedures with respect to reporting of radiation dosimetric information. This article discusses qualitative differences between nuclear medicine and x-ray-based procedures, including differences in the radiation source and measurement of its strength, the impact of biokinetics on dosimetry, and the capability of current scanners to record dosimetry information. These differences create challenges in applying, monitoring, and reporting strategies used in x-ray-based procedures to nuclear medicine, and integrating dosimetry information across modalities. A concerted effort by the medical imaging community, dosimetry specialists, and manufacturers of imaging equipment is required to develop strategies to improve the reporting of radiation dosimetry data in nuclear medicine. Some ideas on how to address this issue are suggested. PMID:22695788

  3. DETERMINING THE EFFECTS OF RADIATION ON AGING CONCRETE STRUCTURES OF NUCLEAR REACTORS

    SciTech Connect

    Serrato, M.

    2010-01-29

    The U.S. Department of Energy Office of Environmental Management (DOE-EM) is responsible for the Decontamination and Decommissioning (D&D) of nuclear facilities throughout the DOE Complex. Some of these facilities will be completely dismantled, while others will be partially dismantled and the remaining structure will be stabilized with cementitious fill materials. The latter is a process known as In-Situ Decommissioning (ISD). The ISD decision process requires a detailed understanding of the existing facility conditions, and operational history. System information and material properties are need for aged nuclear facilities. This literature review investigated the properties of aged concrete structures affected by radiation. In particular, this review addresses the Savannah River Site (SRS) isotope production nuclear reactors. The concrete in the reactors at SRS was not seriously damaged by the levels of radiation exposure. Loss of composite compressive strength was the most common effect of radiation induced damage documented at nuclear power plants.

  4. ANNUAL REPORT. RADIATION EFFECTS IN NUCLEAR WASTE MATERIALS

    EPA Science Inventory

    The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics. This study will provide the underpinning science to develop improved gl...

  5. PROGRESS REPORT. RADIATION EFFECTS IN NUCLEAR WASTE MATERIALS

    EPA Science Inventory

    The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics. This study will provide the underpinning science to develop improved gl...

  6. Comparison of radiation safety and nuclear explosive safety disciplines

    SciTech Connect

    Winstanley, J. L.

    1998-10-10

    In August 1945, U.S. Navy Captain William Parsons served as the weaponeer aboard the Enola Gay for the mission to Hiroshima (Shelton 1988). In view of the fact that four B-29s had crashed and burned on takeoff from Tinian the night before, Captain Parsons made the decision to arm the gun-type weapon after takeoff for safety reasons (15 kilotons of TNT equivalent). Although he had no control over the success of the takeoff, he could prevent the possibility of a nuclear detonation on Tinian by controlling what we now call the nuclear explosive. As head of the Ordnance Division at Los Alamos and a former gunnery officer, Captain Parsons clearly understood the role of safety in his work. The advent of the pre-assembled implosion weapon where the high explosive and nuclear materials are always in an intimate configuration meant that nuclear explosive safety became a reality at a certain point in development and production not just at the time of delivery by the military. This is the only industry where nuclear materials are intentionally put in contact with high explosives. The agency of the U.S. Government responsible for development and production of U.S. nuclear weapons is the Department of Energy (DOE) (and its predecessor agencies). This paper will be limited to nuclear explosive safety as it is currently practiced within the DOE nuclear weapons

  7. Assessment of radiation safety awareness among nuclear medicine nurses: a pilot study

    NASA Astrophysics Data System (ADS)

    Yunus, N. A.; Abdullah, M. H. R. O.; Said, M. A.; Ch'ng, P. E.

    2014-11-01

    All nuclear medicine nurses need to have some knowledge and awareness on radiation safety. At present, there is no study to address this issue in Malaysia. The aims of this study were (1) to determine the level of knowledge and awareness on radiation safety among nuclear medicine nurses at Putrajaya Hospital in Malaysia and (2) to assess the effectiveness of a training program provided by the hospital to increase the knowledge and awareness of the nuclear medicine nurses. A total of 27 respondents attending a training program on radiation safety were asked to complete a questionnaire. The questionnaire consists 16 items and were categorized into two main areas, namely general radiation knowledge and radiation safety. Survey data were collected before and after the training and were analyzed using descriptive statistics and paired sample t-test. Respondents were scored out of a total of 16 marks with 8 marks for each area. The findings showed that the range of total scores obtained by the nuclear medicine nurses before and after the training were 6-14 (with a mean score of 11.19) and 13-16 marks (with a mean score of 14.85), respectively. Findings also revealed that the mean score for the area of general radiation knowledge (7.59) was higher than that of the radiation safety (7.26). Currently, the knowledge and awareness on radiation safety among the nuclear medicine nurses are at the moderate level. It is recommended that a national study be conducted to assess and increase the level of knowledge and awareness among all nuclear medicine nurses in Malaysia.

  8. Summary Report for the Radiation Detection for Nuclear Security Summer School 2012

    SciTech Connect

    Runkle, Robert C.; Baciak, James E.; Stave, Jean A.

    2012-08-22

    The Pacific Northwest National Laboratory (PNNL) hosted students from across the United States at the inaugural Radiation Detection for Nuclear Security Summer School from June 11 – 22, 2012. The summer school provided students with a unique understanding of nuclear security challenges faced in the field and exposed them to the technical foundations, analyses, and insight that will be required by future leaders in technology development and implementation. The course heavily emphasized laboratory and field demonstrations including direct measurements of special nuclear material. The first week of the summer school focused on the foundational knowledge required by technology practitioners; the second week focused on contemporary applications. Student evaluations and feedback from student advisors indicates that the summer school achieved its objectives of 1) exposing students to the range of nuclear security applications for which radiation detection is necessary, 2) articulating the relevance of student research into the broader context, and 3) exciting students about the possibility of future careers in nuclear security.

  9. Effects of nuclear radiation and elevated temperature storage on electroexplosive devices

    NASA Technical Reports Server (NTRS)

    Menichelli, V. J.

    1976-01-01

    Aerospace type electroexplosive devices (EEDs) were subjected to nuclear radiation. Components and chemicals used in the EEDs were also included. The kind of radiation and total dosage administered were those which may be experienced in a space flight of 10 years duration, based on information available at this time. After irradiation, the items were stored in elevated constant-temperature ovens to accelerate early effects of the exposure to radiation. Periodically, samples were withdrawn for visual observation and testing. Significant changes occurred which were attributed to elevated-temperature storage and not radiation.

  10. What Students Think About (Nuclear) Radiation – Before and After Fukushima

    SciTech Connect

    Neumann, S.

    2014-06-15

    Preparing successful science lessons is very demanding. One important aspect a teacher has to consider is the students' previous knowledge about the specific topic. This is why research about students' preconceptions has been, and continues to be, a major field in science education research. Following a constructivistic approach [R. Duit et al., International handbook of research on conceptual change, p. 629 (2008)], helping students learn is only possible if teachers know about students' ideas beforehand. Studies about students' conceptions regarding the major topics in physics education (e.g. mechanics, electrodynamics, optics, thermodynamics), are numerous and well-documented. The topic radiation, however, has seen very little empirical research about students' ideas and misconceptions. Some research was conducted after the events of Chernobyl [P. Lijnse et al., International Journal of Science Education 12, 67 (1990); B. Verplanken, Environment and Behavior 21, 7 (1989)] and provided interesting insight into some of the students' preconceptions about radiation. In order to contribute empirical findings to this field of research, our workgroup has been investigating the conceptions students have about the topic radiation for several years [S. Neumann et al., Journal of Science Education and Technology 21, 826 (2012)]. We used children's drawings and conducted short follow-up interviews with students (9 – 12 years old) and more detailed interviews with 15-year-old students. Both studies were originally done before the events in Fukushima and replicated a year later. We not only asked students about their general associations and emotions regarding the term radiation, but also examined the students' risk perceptions of different types of radiation. Through the use of open-ended questions we were able to examine students' conceptions about different types of radiation (including nuclear) that could be a hindrance to student learning. Our results show that

  11. Current global and Korean issues in radiation safety of nuclear medicine procedures.

    PubMed

    Song, H C

    2016-06-01

    In recent years, the management of patient doses in medical imaging has evolved as concern about radiation exposure has increased. Efforts and techniques to reduce radiation doses are focussed not only on the basis of patient safety, but also on the fundamentals of justification and optimisation in cooperation with international organisations such as the International Commission on Radiological Protection, the International Atomic Energy Agency, and the World Health Organization. The Image Gently campaign in children and Image Wisely campaign in adults to lower radiation doses have been initiated in the USA. The European Association of Nuclear Medicine paediatric dosage card, North American consensus guidelines, and Nuclear Medicine Global Initiative have recommended the activities of radiopharmaceuticals that should be administered in children. Diagnostic reference levels (DRLs), developed predominantly in Europe, may be an important tool to manage patient doses. In Korea, overexposure to radiation, even from the use of medical imaging, has become a public issue, particularly since the accident at the Fukushima nuclear power plant. As a result, the Korean Nuclear Safety and Security Commission revised the technical standards for radiation safety management in medical fields. In parallel, DRLs for nuclear medicine procedures have been collected on a nationwide scale. Notice of total effective dose from positron emission tomography-computed tomography for cancer screening has been mandatory since mid-November 2014. PMID:26960820

  12. Nuclear Energy and Health: And the Benefits of Low-Dose Radiation Hormesis

    PubMed Central

    Cuttler, Jerry M.; Pollycove, Myron

    2009-01-01

    Energy needs worldwide are expected to increase for the foreseeable future, but fuel supplies are limited. Nuclear reactors could supply much of the energy demand in a safe, sustainable manner were it not for fear of potential releases of radioactivity. Such releases would likely deliver a low dose or dose rate of radiation, within the range of naturally occurring radiation, to which life is already accustomed. The key areas of concern are discussed. Studies of actual health effects, especially thyroid cancers, following exposures are assessed. Radiation hormesis is explained, pointing out that beneficial effects are expected following a low dose or dose rate because protective responses against stresses are stimulated. The notions that no amount of radiation is small enough to be harmless and that a nuclear accident could kill hundreds of thousands are challenged in light of experience: more than a century with radiation and six decades with reactors. If nuclear energy is to play a significant role in meeting future needs, regulatory authorities must examine the scientific evidence and communicate the real health effects of nuclear radiation. Negative images and implications of health risks derived by unscientific extrapolations of harmful effects of high doses must be dispelled. PMID:19343116

  13. Nuclear-radiation-actuated valve. [Patent application; for increasing coolant flow to blanket

    DOEpatents

    Christiansen, D.W.; Schively, D.P.

    1982-01-19

    The present invention relates to a breeder reactor blanket fuel assembly coolant system valve which increases coolant flow to the blanket fuel assembly to minimize long-term temperature increases caused by fission of fissile fuel created from fertile fuel through operation of the breeder reactor. The valve has a valve first part (such as a valve rod with piston) and a valve second part (such as a valve tube surrounding the valve rod, with the valve tube having side slots surrounding the piston). Both valve parts have known nuclear radiation swelling characteristics. The valve's first part is positioned to receive nuclear radiation from the nuclear reactor's fuel region. The valve's second part is positioned so that its nuclear radiation induced swelling is different from that of the valve's first part. The valve's second part also is positioned so that the valve's first and second parts create a valve orifice which changes in size due to the different nuclear radiation caused swelling of the valve's first part compared to the valve's second part. The valve may be used in a nuclear reactor's core coolant system.

  14. Experimental study of variations in background radiation and the effect on Nuclear Car Wash sensitivity

    SciTech Connect

    Church, J; Slaughter, D; Norman, E; Asztalos, S; Biltoft, P

    2007-02-07

    Error rates in a cargo screening system such as the Nuclear Car Wash [1-7] depend on the standard deviation of the background radiation count rate. Because the Nuclear Car Wash is an active interrogation technique, the radiation signal for fissile material must be detected above a background count rate consisting of cosmic, ambient, and neutron-activated radiations. It was suggested previously [1,6] that the Corresponding negative repercussions for the sensitivity of the system were shown. Therefore, to assure the most accurate estimation of the variation, experiments have been performed to quantify components of the actual variance in the background count rate, including variations in generator power, irradiation time, and container contents. The background variance is determined by these experiments to be a factor of 2 smaller than values assumed in previous analyses, resulting in substantially improved projections of system performance for the Nuclear Car Wash.

  15. Radiation environment for rendezvous and docking with nuclear rockets

    NASA Technical Reports Server (NTRS)

    Rogers, D. R.; Warman, E. A.; Lindsey, B. A.

    1972-01-01

    Radiation environment data for the NERVA engine are provided which may be utilized in estimating radiation exposures associated with various space maneuvers. Spatial distributions of neutron and gamma tissue kerma rates produced during full thrust operation of the engine are presented. Final rendezvous with an orbiting space station would be achieved subsequent to full thrust operation during a period of 10 or more hours duration in which impulse is delivered by the propellant used for removal of decay heat. Consequently, post operation radiation levels are of prime importance in estimating space station exposures. Maps of gamma kerma rates around the engine are provided for decay times of 4 and 24 hours after a representative firing. Typical decay curves illustrating the dependence of post operation kerma rates on decay time and operating history are included. Examples of the kerma distributions around the engine which result from integration over specific exposure periods are shown.

  16. Nuclear forward scattering of synchrotron radiation by 99Ru

    DOE PAGESBeta

    Bessas, D.; Merkel, D. G.; Chumakov, A. I.; Ruffer, R.; Hermann, Raphael P.; Sergueev, I.; Mahmoud, A.; Klobes, B.; McGuire, Michael A.; Sougrati, M. T.; et al

    2014-10-03

    In this study, we measured nuclear forward scattering spectra utilizing the 99Ru transition, 89.571(3) keV, with a notably mixed E2/M1 multipolarity. The extension of the standard evaluation routines to include mixed multipolarity allows us to extract electric and magnetic hyperfine interactions from 99Ru-containing compounds. This paves the way for several other high-energy Mössbauer transitions, E~90 keV. Lastly, the high energy of such transitions allows for operando nuclear forward scattering studies in real devices.

  17. Perception of Radiation Risk by Japanese Radiation Specialists Evaluated as a Safe Dose Before the Fukushima Nuclear Accident.

    PubMed

    Miura, Miwa; Ono, Koji; Yamauchi, Motohiro; Matsuda, Naoki

    2016-06-01

    From October to December 2010, just before the radiological accident at the Fukushima Daiichi nuclear power plant, 71 radiation professionals from radiation facilities in Japan were asked what they considered as a "safe dose" of radiation for themselves, their partners, parents, children, siblings, and friends. Although the 'safe dose' they noted varied widely, from less than 1 mSv y to more than 100 mSv y, the average dose was 35.6 mSv y, which is around the middle point between the legal exposure dose limits for the annual average and for any single year. Similar results were obtained from other surveys of members of the Japan Radioisotope Association (36.9 mSv y) and of the Oita Prefectural Hospital (36.8 mSv y). Among family members and friends, the minimum average "safe" dose was 8.5 mSv y for children, for whom 50% of the responders claimed a "safe dose" of less than 1 mSv. Gender, age and specialty of the radiation professional also affected their notion of a "safe dose." These findings suggest that the perception of radiation risk varies widely even for radiation professionals and that the legal exposure dose limits derived from regulatory science may act as an anchor of safety. The different levels of risk perception for different target groups among radiation professionals appear similar to those in the general population. The gap between these characteristics of radiation professionals and the generally accepted picture of radiation professionals might have played a role in the state of confusion after the radiological accident. PMID:27115222

  18. Building the strategic national stockpile through the NIAID Radiation Nuclear Countermeasures Program.

    PubMed

    Rios, Carmen I; Cassatt, David R; Dicarlo, Andrea L; Macchiarini, Francesca; Ramakrishnan, Narayani; Norman, Mai-Kim; Maidment, Bert W

    2014-02-01

    The possibility of a public health radiological or nuclear emergency in the United States remains a concern. Media attention focused on lost radioactive sources and international nuclear threats, as well as the potential for accidents in nuclear power facilities (e.g., Windscale, Three Mile Island, Chernobyl, and Fukushima) highlight the need to address this critical national security issue. To date, no drugs have been licensed to mitigate/treat the acute and long-term radiation injuries that would result in the event of large-scale, radiation, or nuclear public health emergency. However, recent evaluation of several candidate radiation medical countermeasures (MCMs) has provided initial proof-of-concept of efficacy. The goal of the Radiation Nuclear Countermeasures Program (RNCP) of the National Institute of Allergy and Infectious Diseases (National Institutes of Health) is to help ensure the government stockpiling of safe and efficacious MCMs to treat radiation injuries, including, but not limited to, hematopoietic, gastrointestinal, pulmonary, cutaneous, renal, cardiovascular, and central nervous systems. In addition to supporting research in these areas, the RNCP continues to fund research and development of decorporation agents targeting internal radionuclide contamination, and biodosimetry platforms (e.g., biomarkers and devices) to assess the levels of an individual's radiation exposure, capabilities that would be critical in a mass casualty scenario. New areas of research within the program include a focus on special populations, especially pediatric and geriatric civilians, as well as combination studies, in which drugs are tested within the context of expected medical care management (e.g., antibiotics and growth factors). Moving forward, challenges facing the RNCP, as well as the entire radiation research field, include further advancement and qualification of animal models, dose conversion from animal models to humans, biomarker identification, and

  19. Mixed-radiation-field dosimetry utilizing Nuclear Quadrupole Resonance

    SciTech Connect

    Hintenlang, D.E.; Jamil, K.; Iselin, L.H.

    1992-01-01

    Radiation effects on urea, thiourea, guanidine carbonate and guanine sulfate were evaluated for both photon and neutron irradiations. Hydration of these materials typically provides a greatly increased sensitivity to both forms of radiation exposure, although not all materials lend themselves to this treatment without changing the chemical structure of the compound. Urea was found to be the most stable hydrated compound and provides the best sensitivity for quantifying radiation effects using NQR techniques. Urea permits a straight-forward quantification of each of the important parameters of the observed NQR signal, the FID. Several advanced data analysis methods were developed to assist in quantifying NQR spectra, both from urea and materials having more complex molecular structures, such as thiourea and guanidine sulfate. Unfortunately, these analysis techniques are frequently quite time consuming for the complex NQR spectra that result from some of these materials. The simpler analysis afforded by urea has therefore made it the prime candidate for an NQR dosimetry material. The moderate sensitivity of hydrated urea to photon irradiation does not permit this material to achieve the levels of performance required for a personnel dosimeter. It does, however, demonstrate acceptable sensitivity over dose ranges where it could provide a good biological dosimeter for several areas of radiation processing. The demonstrated photon sensitivity could permit hydrated urea to be used in applications such as food irradiation dosimetry. This material also exhibits a good sensitivity to neutron irradiation. The precise correlation between neutron exposure and the parameters of the resulting NQR spectra are currently being developed.

  20. Compact endocavity diagnostic probes for nuclear radiation detection

    DOEpatents

    Cui, Yonggang; James, Ralph; Bolotnikov, Aleksey

    2014-08-26

    This invention relates to the field of radiation imaging. In particular, the invention relates to an apparatus and a method for imaging tissue or an inanimate object using a novel probe that has an integrated solid-state semiconductor detector and complete readout electronics circuitry.

  1. MOX LTA Fuel Cycle Analyses: Nuclear and Radiation Safety

    SciTech Connect

    Pavlovitchev, A.M.

    2001-09-28

    Tasks of nuclear safety assurance for storage and transport of fresh mixed uranium-plutonium fuel of the VVER-1000 reactor are considered in the view of 3 MOX LTAs introduction into the core. The precise code MCU that realizes the Monte Carlo method is used for calculations.

  2. Application of Radiation Chemistry to Some Selected Technological Issues Related to the Development of Nuclear Energy.

    PubMed

    Bobrowski, Krzysztof; Skotnicki, Konrad; Szreder, Tomasz

    2016-10-01

    The most important contributions of radiation chemistry to some selected technological issues related to water-cooled reactors, reprocessing of spent nuclear fuel and high-level radioactive wastes, and fuel evolution during final radioactive waste disposal are highlighted. Chemical reactions occurring at the operating temperatures and pressures of reactors and involving primary transients and stable products from water radiolysis are presented and discussed in terms of the kinetic parameters and radiation chemical yields. The knowledge of these parameters is essential since they serve as input data to the models of water radiolysis in the primary loop of light water reactors and super critical water reactors. Selected features of water radiolysis in heterogeneous systems, such as aqueous nanoparticle suspensions and slurries, ceramic oxides surfaces, nanoporous, and cement-based materials, are discussed. They are of particular concern in the primary cooling loops in nuclear reactors and long-term storage of nuclear waste in geological repositories. This also includes radiation-induced processes related to corrosion of cladding materials and copper-coated iron canisters, dissolution of spent nuclear fuel, and changes of bentonite clays properties. Radiation-induced processes affecting stability of solvents and solvent extraction ligands as well oxidation states of actinide metal ions during recycling of the spent nuclear fuel are also briefly summarized. PMID:27573502

  3. Autophagy confers DNA damage repair pathways to protect the hematopoietic system from nuclear radiation injury

    PubMed Central

    Lin, Weiwei; Yuan, Na; Wang, Zhen; Cao, Yan; Fang, Yixuan; Li, Xin; Xu, Fei; Song, Lin; Wang, Jian; Zhang, Han; Yan, Lili; Xu, Li; Zhang, Xiaoying; Zhang, Suping; Wang, Jianrong

    2015-01-01

    Autophagy is essentially a metabolic process, but its in vivo role in nuclear radioprotection remains unexplored. We observed that ex vivo autophagy activation reversed the proliferation inhibition, apoptosis, and DNA damage in irradiated hematopoietic cells. In vivo autophagy activation improved bone marrow cellularity following nuclear radiation exposure. In contrast, defective autophagy in the hematopoietic conditional mouse model worsened the hematopoietic injury, reactive oxygen species (ROS) accumulation and DNA damage caused by nuclear radiation exposure. Strikingly, in vivo defective autophagy caused an absence or reduction in regulatory proteins critical to both homologous recombination (HR) and non-homologous end joining (NHEJ) DNA damage repair pathways, as well as a failure to induce these proteins in response to nuclear radiation. In contrast, in vivo autophagy activation increased most of these proteins in hematopoietic cells. DNA damage assays confirmed the role of in vivo autophagy in the resolution of double-stranded DNA breaks in total bone marrow cells as well as bone marrow stem and progenitor cells upon whole body irradiation. Hence, autophagy protects the hematopoietic system against nuclear radiation injury by conferring and intensifying the HR and NHEJ DNA damage repair pathways and by removing ROS and inhibiting apoptosis. PMID:26197097

  4. 169Tm-A new candidate for monochromatization of synchrotron radiation by nuclear Bragg diffraction

    NASA Astrophysics Data System (ADS)

    Sturhahn, W.; Gerdau, E.; Börger, S.; Guse, W.

    1990-07-01

    Thulium containing crystals with appropriate structure should be feasible for monochromatizing synchrotron radiation by nuclear Bragg diffraction. Thulium iron garnet and thulium gallium garnet were investigated by MB-transmission spectroscopy. The evaluated hyperfine interactions are discussed with respect to the crystal structure. The occurrence of pure nuclear reflections is predicted and theoretical time spectra are calculated by the dynamical theory of MB-optics.

  5. Shadow Radiation Shield Required Thickness Estimation for Space Nuclear Power Units

    NASA Astrophysics Data System (ADS)

    Voevodina, E. V.; Martishin, V. M.; Ivanovsky, V. A.; Prasolova, N. O.

    The paper concerns theoretical possibility of visiting orbital transport vehicles based on nuclear power unit and electric propulsion system on the Earth's orbit by astronauts to maintain work with payload from the perspective of radiation safety. There has been done estimation of possible time of the crew's staying in the area of payload of orbital transport vehicles for different reactor powers, which is a consistent part of nuclear power unit.

  6. Upgrading of data acquisition software for centralized radiation monitoring system in Malaysian Nuclear Agency

    NASA Astrophysics Data System (ADS)

    Yussup, F.; Ibrahim, M. M.; Haris, M. F.; Soh, S. C.; Hasim, H.; Azman, A.; Razalim, F. A. A.; Yapp, R.; Ramli, A. A. M.

    2016-01-01

    With the growth of technology, many devices and equipments can be connected to the network and internet to enable online data acquisition for real-time data monitoring and control from monitoring devices located at remote sites. Centralized radiation monitoring system (CRMS) is a system that enables area radiation level at various locations in Malaysian Nuclear Agency (Nuklear Malaysia) to be monitored centrally by using a web browser. The Local Area Network (LAN) in Nuclear Malaysia is utilized in CRMS as a communication media for data acquisition of the area radiation levels from radiation detectors. The development of the system involves device configuration, wiring, network and hardware installation, software and web development. This paper describes the software upgrading on the system server that is responsible to acquire and record the area radiation readings from the detectors. The recorded readings are called in a web programming to be displayed on a website. Besides the main feature which is acquiring the area radiation levels in Nuclear Malaysia centrally, the upgrading involves new features such as uniform time interval for data recording and exporting, warning system and dose triggering.

  7. Lunar and Martian environmental interactions with nuclear power system radiators

    SciTech Connect

    Perez-Davis, M.E.; Gaier, J.R.; Katzan, C.M.

    1994-09-01

    In the foreseeable future, NASA space milestones include a permanent manned presence on the Moon and an expedition to the planet Mars. Such steps will require careful consideration of environmental interactions in the selection and design of required power systems. Several environmental constituents may be hazardous to performance integrity. Potential threats common to both the Moon and Mars are low ambient temperatures, wide daily temperature swings, solar flux, and large quantities of dust. The surface of Mars provides the additional challenges of dust storms, winds, and a carbon dioxide atmosphere. In this review, the anticipated environmental interactions with surface power system radiators are described, as well as the impacts of these interactions on radiator durability, which have been identified at NASA Lewis Research Center.

  8. Lunar and Martian environmental interactions with nuclear power system radiators

    NASA Technical Reports Server (NTRS)

    Perez-Davis, Marla E.; Gaier, James R.; Katzan, Cynthia M.

    1992-01-01

    Future NASA space missions include a permanent manned presence on the moon and an expedition to the planet Mars. Such steps will require careful consideration of environmental interactions in the selection and design of required power systems. Several environmental constituents may be hazardous to performance integrity. Potential threats common to both the moon and Mars are low ambient temperatures, wide daily temperature swings, solar flux, and large quantities of dust. The surface of Mars provides the additional challenges of dust storms, winds, and a carbon dioxide atmosphere. In this review, the anticipated environmental interactions with surface power system radiators are described, as well as the impacts of these interactions on radiator durability, which were identified at NASA Lewis Research Center.

  9. Hand exposure to ionising radiation of nuclear medicine workers.

    PubMed

    Wrzesień, M; Olszewski, J; Jankowski, J

    2008-01-01

    The specific nature of work in nuclear medicine departments involves the use of isotopes and handling procedures, which contribute to the considerable value of an equivalent dose received, in particular, by the fingertips. Standard nuclear medicine department uses ring dosemeters placed usually at the base of the middle finger. The main aim of the study was to find out whether a relationship exists between the doses recorded by thermoluminescent detectors placed at various locations on the radiopharmacists' hands and the doses recorded by the ring detectors, and to determine the character of that relationship. The correction factor represents a correction value to be used to calculate the doses which might be received by locations on the hand from the dose recorded by the ring dosemeter. The dose recorded by the ring dosemeter is on the average five times lower than that received by the fingertips of thumb, index and middle fingers. PMID:18310609

  10. Fabrication techniques for reverse electrode coaxial germanium nuclear radiation detectors

    SciTech Connect

    Hansen, W.L.; Haller, E.E.

    1980-11-01

    Germanium detectors with reverse polarity coaxial electrodes have been shown to exhibit improved resistance to radiation damage as compared with conventional electrode devices. However, the production of reverse electrode devices involves the development of new handling and fabrication techniques which has limited their wider application. We have developed novel techniques which lead to a device which is simple to fabricate, environmentally passivated and surface state adjusted.

  11. An Overview of the Regulation of Low Dose Radiation in the Nuclear and Non-nuclear Industries

    SciTech Connect

    Menon, Shankar; Valencia, Luis; Teunckens, Lucien

    2003-02-27

    Now that increasing numbers of nuclear power stations are reaching the end of their commercially useful lives, the management of the large quantities of very low level radioactive material that arises during their decommissioning has become a major subject of discussion, with very significant economic implications. Much of this material can, in an environmentally advantageous manner, be recycled for reuse without radiological restrictions. Much larger quantities--2-3 orders of magnitude larger--of material, radiologically similar to the candidate material for recycling from the nuclear industry, arise in non-nuclear industries like coal, fertilizer, oil and gas, mining, etc. In such industries, naturally occurring radioactivity is artificially concentrated in products, by-products or waste to form TENORM (Technologically Enhanced Naturally Occurring Radioactive Material). It is only in the last decade that the international community has become aware of the prevalence of TENORM, specially the activity levels and quantities arising in so many non-nuclear industries. The first reaction of international organizations seems to have been to propose different standards for the nuclear and non-nuclear industries, with very stringent release criteria for radioactive material from the regulated nuclear industry and up to thirty to a hundred times more liberal criteria for the release/exemption of TENORM from the as yet unregulated non-nuclear industries. There are significant strategic issues that need to be discussed and resolved. Some examples of these are: - Disposal aspects of long-lived nuclides, - The use of radioactive residues in building materials, - Commercial aspects of differing and discriminating criteria in competing power industries in a world of deregulated electric power production. Of even greater importance is the need for the discussion of certain basic issues, such as - The quantitative risk levels of exposure to ionizing radiation, - The need for in

  12. Radiation safety in nuclear medicine: a practical guide. Final report

    SciTech Connect

    Sodd, V.J.

    1981-11-01

    This publication brings together, in concise form, information regarding the many recommendations and requirements for safe operation of a nuclear medicine laboratory. The need for such a compendium was perceived by the staff of the Nuclear Medicine Laboratory. This need arises from several sources. Many individuals enter the field with little training in the handling of radioactive materials; for example, a physician trained in cardiology, oncology, or neurology. The increasing development of portable instrumentation has allowed movement of radiopharmaceuticals from the confines of the nuclear medicine lab to coronary and intensive care facilities where personnel may lack adequate knowledge of safe handling procedures. A health physicist, trained to account for all radioactive material placed under his control, may have difficulty adapting to the accepted practice of releasing a patient who has been administered millicurie quantities of radioactivity, with little or no control over subsequent disposal of excreta. Further differences exist between handling practices for radioactive materials in the scientific laboratory and in the medical facility. This guide tries where possible to clarify some of these issues.

  13. Enhancing international radiation/nuclear detection training opportunities

    SciTech Connect

    Williams, Thomas L.; Bersell, Bridget M.; Booker, Paul M.; Anderson, Gerald E.; Leitch, Rosalyn M.; Meagher, John B.; Siefken, Rob R.; Spracklen, James L.

    2015-09-23

    The United States has worked domestically to develop and provide radiological and nuclear detection training and education initiatives aimed at interior law enforcement, but the international community has predominantly focused efforts at border and customs officials. The interior law enforcement officials of a State play a critical role in maintaining an effective national-level nuclear detection architecture. To meet this vital need, DNDO was funded by the U.S. Department of State (DOS) to create and deliver a 1-week course at the International Law Enforcement Academy (ILEA) in Budapest, Hungary to inform interior law enforcement personnel of the overall mission, and to provide an understanding of how the participants can combat the threats of radiological and nuclear terrorism through detection efforts. Two courses, with approximately 20 students in each course, were delivered in fiscal year (FY) 2013, two were delivered in FY 2014 and FY 2015, and as of this report’s writing more are planned in FY 2016. However, while the ILEA courses produced measurable success, DNDO requested Pacific Northwest National Laboratory (PNNL) research potential avenues to further increase the course impact.In a multi-phased approach, PNNL researched and analyzed several possible global training locations and venues, and other possible ways to increase the impact of the course using an agreed-to data-gathering format.

  14. Radiation risk and nuclear medicine: An interview with a Nobel Prize winner

    SciTech Connect

    Yalow, R.S.

    1995-12-01

    In a speech given years ago at the Veterans Administration Medical Center, Bronx, NY, Rosalyn S. Yalow, 1977 Nobel Prize recipient for her invention of radioimmunoassay, made several salient points on the perception of fear or hazards from exposure to low-level radiation and low-level radioactive wastes. For the past three years, Yalow has been concerned with the general fear of radiation. In this interview, Newsline solicited Yalow`s views on public perceptions on radiation risk and what the nuclear medicine community can do to emphasize the fact that, if properly managed, the use of isotopes in medicine and other cases is not dangerous.

  15. Evaluation of 133Xe radiation exposure dosimetry for workers in nuclear medicine laboratories.

    PubMed

    Piltingsrud, H V; Gels, G L

    1982-06-01

    Evaluation of past studies of 133Xe dosimetry and nuclear medicine laboratory air concentrations of 133Xe indicates that significant levels of 133Xe may exist in routine operational environments of a nuclear medicine laboratory. This leads to the question of whether present health physics radiation control methods are adequate to keep occupational personnel exposures within acceptable levels. It would appear that if personnel dosimeters (film and TLD badges) respond properly to the radiation of 133Xe, normal health physics control procedures are probably adequate. If they do not respond adequately, personnel exposures may exceed recommended levels and special instrumentation or administrative procedures are called for. Therefore, the first step in studying potential problems in the subject area is to evaluate the response of a variety of personnel radiation dosimeters to 133Xe. This paper describes the methods and materials used to expose personnel dosimeters to known amounts of 133Xe radiations in an exposure chamber constructed at the BRH Nuclear Medicine Laboratory. Also presented are calculated values for Dose Equivalents (D.E.) in a phantom from external radiation resulting from immersion in clouds having a constant concentration of 133Xe but varying cloud radii. This implies the relative importance of the beta and the X + gamma radiation responses of the personnel dosimeters under various exposure conditions. Results of this study indicate that none of the dosimeter systems evaluated provide adequate performance for use as a primary indicator of the D.E. resulting from 133Xe radiations for a worker in a nuclear medicine laboratory, and that personnel dosimetry considerations in 133Xe-containing atmospheres are very dependent on the radii of the 133Xe clouds. PMID:7107291

  16. Limited internal radiation exposure associated with resettlements to a radiation-contaminated homeland after the Fukushima Daiichi nuclear disaster.

    PubMed

    Tsubokura, Masaharu; Kato, Shigeaki; Nihei, Masahiko; Sakuma, Yu; Furutani, Tomoyuki; Uehara, Keisuke; Sugimoto, Amina; Nomura, Shuhei; Hayano, Ryugo; Kami, Masahiro; Watanobe, Hajime; Endo, Yukou

    2013-01-01

    Resettlement to their radiation-contaminated hometown could be an option for people displaced at the time of a nuclear disaster; however, little information is available on the safety implications of these resettlement programs. Kawauchi village, located 12-30 km southwest of the Fukushima Daiichi nuclear power plant, was one of the 11 municipalities where mandatory evacuation was ordered by the central government. This village was also the first municipality to organize the return of the villagers. To assess the validity of the Kawauchi villagers' resettlement program, the levels of internal Cesium (Cs) exposures were comparatively measured in returnees, commuters, and non-returnees among the Kawauchi villagers using a whole body counter. Of 149 individuals, 5 villagers had traceable levels of Cs exposure; the median detected level was 333 Bq/body (range, 309-1050 Bq/kg), and 5.3 Bq/kg (range, 5.1-18.2 Bq/kg). Median annual effective doses of villagers with traceable Cs were 1.1 x 10(-2) mSv/y (range, 1.0 x 10(-2)-4.1 x 10(-2) mSv/y). Although returnees had higher chances of consuming locally produced vegetables, Cochran-Mantel-Haenszel test showed that their level of internal radiation exposure was not significantly higher than that in the other 2 groups (p=0.643). The present findings in Kawauchi village imply that it is possible to maintain internal radiation exposure at very low levels even in a highly radiation-contaminated region at the time of a nuclear disaster. Moreover, the risks for internal radiation exposure could be limited with a strict food control intervention after resettlement to the radiation-contaminated village. It is crucial to establish an adequate number of radio-contaminated testing sites within the village, to provide immediate test result feedback to the villagers, and to provide education regarding the importance of re-testing in reducing the risk of high internal radiation exposure. PMID:24312602

  17. Limited Internal Radiation Exposure Associated with Resettlements to a Radiation-Contaminated Homeland after the Fukushima Daiichi Nuclear Disaster

    PubMed Central

    Tsubokura, Masaharu; Kato, Shigeaki; Nihei, Masahiko; Sakuma, Yu; Furutani, Tomoyuki; Uehara, Keisuke; Sugimoto, Amina; Nomura, Shuhei; Hayano, Ryugo; Kami, Masahiro; Watanobe, Hajime; Endo, Yukou

    2013-01-01

    Resettlement to their radiation-contaminated hometown could be an option for people displaced at the time of a nuclear disaster; however, little information is available on the safety implications of these resettlement programs. Kawauchi village, located 12–30 km southwest of the Fukushima Daiichi nuclear power plant, was one of the 11 municipalities where mandatory evacuation was ordered by the central government. This village was also the first municipality to organize the return of the villagers. To assess the validity of the Kawauchi villagers’ resettlement program, the levels of internal Cesium (Cs) exposures were comparatively measured in returnees, commuters, and non-returnees among the Kawauchi villagers using a whole body counter. Of 149 individuals, 5 villagers had traceable levels of Cs exposure; the median detected level was 333 Bq/body (range, 309–1050 Bq/kg), and 5.3 Bq/kg (range, 5.1–18.2 Bq/kg). Median annual effective doses of villagers with traceable Cs were 1.1 x 10-2 mSv/y (range, 1.0 x 10-2-4.1 x 10-2 mSv/y). Although returnees had higher chances of consuming locally produced vegetables, Cochran-Mantel-Haenszel test showed that their level of internal radiation exposure was not significantly higher than that in the other 2 groups (p=0.643). The present findings in Kawauchi village imply that it is possible to maintain internal radiation exposure at very low levels even in a highly radiation-contaminated region at the time of a nuclear disaster. Moreover, the risks for internal radiation exposure could be limited with a strict food control intervention after resettlement to the radiation-contaminated village. It is crucial to establish an adequate number of radio-contaminated testing sites within the village, to provide immediate test result feedback to the villagers, and to provide education regarding the importance of re-testing in reducing the risk of high internal radiation exposure. PMID:24312602

  18. Integrated Radiation Transport and Nuclear Fuel Performance for Assembly-Level Simulations

    SciTech Connect

    Clarno, Kevin T; Hamilton, Steven P; Philip, Bobby; Berrill, Mark A; Sampath, Rahul S; Allu, Srikanth; Pugmire, Dave; Dilts, Gary; Banfield, James E

    2012-02-01

    The Advanced Multi-Physics (AMP) Nuclear Fuel Performance code (AMPFuel) is focused on predicting the temperature and strain within a nuclear fuel assembly to evaluate the performance and safety of existing and advanced nuclear fuel bundles within existing and advanced nuclear reactors. AMPFuel was extended to include an integrated nuclear fuel assembly capability for (one-way) coupled radiation transport and nuclear fuel assembly thermo-mechanics. This capability is the initial step toward incorporating an improved predictive nuclear fuel assembly modeling capability to accurately account for source-terms and boundary conditions of traditional (single-pin) nuclear fuel performance simulation, such as the neutron flux distribution, coolant conditions, and assembly mechanical stresses. A novel scheme is introduced for transferring the power distribution from the Scale/Denovo (Denovo) radiation transport code (structured, Cartesian mesh with smeared materials within each cell) to AMPFuel (unstructured, hexagonal mesh with a single material within each cell), allowing the use of a relatively coarse spatial mesh (10 million elements) for the radiation transport and a fine spatial mesh (3.3 billion elements) for thermo-mechanics with very little loss of accuracy. In addition, a new nuclear fuel-specific preconditioner was developed to account for the high aspect ratio of each fuel pin (12 feet axially, but 1 4 inches in diameter) with many individual fuel regions (pellets). With this novel capability, AMPFuel was used to model an entire 17 17 pressurized water reactor fuel assembly with many of the features resolved in three dimensions (for thermo-mechanics and/or neutronics), including the fuel, gap, and cladding of each of the 264 fuel pins; the 25 guide tubes; the top and bottom structural regions; and the upper and lower (neutron) reflector regions. The final, full assembly calculation was executed on Jaguar using 40,000 cores in under 10 hours to model over 162

  19. Real-time noise mitigation algorithms for space and nuclear radiation environments

    NASA Astrophysics Data System (ADS)

    Redmond, Neal J.; Hill, Janeil; Lowell, Robert; Byers, Wheaton; Retzler, John P.; Andrews, Allen R.; Mackin, Paul R.

    1997-10-01

    This paper addresses small targets and signal processing from the perspective of rejecting radiation noise spikes. Nuclear and space radiation create noise spikes inside infrared detectors causing an overwhelming number of false alarms, if steps are not taken to mitigate the radiation noise spikes. Traditional radiation device/circuit hardening methods are effective, but must be reapplied to each new technology forcing special design point solutions and parts that are increasingly economically nonviable. Real-time noise mitigation algorithms represent a general hardening solution and have been demonstrated for both interceptor seeker and space surveillance sensor applications. A new combined HWIL/radiation synthetic test environment has been developed that enables real-time algorithm evaluation over the total system performance envelope, under flight motion simulation and fully dynamic optical sensor scene stimulation. This work was sponsored by the Defense Special Weapons Agency.

  20. Dosimetry experiences and lessons learned for radiation dose assessment in Korean nuclear power plants.

    PubMed

    Choi, Jong Rak; Kim, Hee Geun; Kong, Tae Young; Son, Jung Kwon

    2013-07-01

    Since the first Korean nuclear power plant (NPP), Kori 1, commenced operation in 1978, a total of 21 NPPs had been put into operation in Korea by the end of 2011. Radiation doses of NPP workers have been periodically evaluated and controlled within the prescribed dose limit. Radiation dose assessment is carried out monthly by reading personal dosemeters for external radiation exposure, which have traceability in compliance with strict technical guidelines. In the case of the internal radiation exposure, workers who have access to the possible area of polluted air are also evaluated for their internal dose after maintenance task. In this article, the overall situation and experience for the assessment and distribution of radiation doses in Korean NPPs is described. PMID:23204558

  1. Radiation-hardened CMOS integrated circuit development for space nuclear power applications

    NASA Astrophysics Data System (ADS)

    Gover, J. E.; Gregory, B. L.

    Examination of the types of systems required for space nuclear power applications suggests a need for microelectronics technology that can function during and after exposure to radiation levels exceeding 1 x 10 to the 16th neutrons/sq cm and gamma ray doses in excess of 1 x 10 to the 7th rad(Si). Radiation-hardened Complimentary Metal Oxide Silicon and Silicon Nitride Oxide Silicon (SNOS) ICs presently in development at Sandia National Laboratories' Center for Radiation-Hardened Microelectronics satisfy these radiation requirements. Future integrated circuit development will further advance the radiation hardness capabilities while extending the IC technology to 32-bit enhanced microprocessors and 1-Mbyte SNOS EEPROM memories.

  2. 42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Medicine Technologists, and Radiation Therapy Technologists F Appendix F to Part 75 Public Health PUBLIC..., App. F Appendix F to Part 75—Standards for Licensing Radiographers, Nuclear Medicine Technologists... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

  3. 42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Medicine Technologists, and Radiation Therapy Technologists F Appendix F to Part 75 Public Health PUBLIC..., App. F Appendix F to Part 75—Standards for Licensing Radiographers, Nuclear Medicine Technologists... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

  4. 42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Medicine Technologists, and Radiation Therapy Technologists F Appendix F to Part 75 Public Health PUBLIC..., App. F Appendix F to Part 75—Standards for Licensing Radiographers, Nuclear Medicine Technologists... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

  5. 42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Medicine Technologists, and Radiation Therapy Technologists F Appendix F to Part 75 Public Health PUBLIC..., App. F Appendix F to Part 75—Standards for Licensing Radiographers, Nuclear Medicine Technologists... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

  6. 42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Medicine Technologists, and Radiation Therapy Technologists F Appendix F to Part 75 Public Health PUBLIC..., App. F Appendix F to Part 75—Standards for Licensing Radiographers, Nuclear Medicine Technologists... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

  7. Offsite environmental monitoring report. Radiation monitoring around United States nuclear test areas, calendar year 1982

    SciTech Connect

    Black, S. C.; Grossman, R. F.; Mullen, A. A.; Potter, G. D.; Smith, D. D.

    1983-07-01

    A principal activity of the Offsite Radiological Safety Program is routine environmental monitoring for radioactive materials in various media and for radiation in areas which may be affected by nuclear tests. It is conducted to document compliance with standards, to identify trends, and to provide information to the public. This report summarizes these activities for CY 1982.

  8. OFFSITE ENVIRONMENTAL MONITORING REPORT. RADIATION MONITORING AROUND UNITED STATES NUCLEAR TEST AREAS, CALENDAR YEAR 1983

    EPA Science Inventory

    This report covers the routine radiation monitoring activities conducted by the Environmental Monitoring Systems Laboratory-Las Vegas in areas which may be affected by nuclear testing programs of the Department of Energy. This monitoring is conducted to document compliance with s...

  9. What You Should Know About Pediatric Nuclear Medicine and Radiation Safety

    MedlinePlus

    ... the Pediatric Imaging Council of the Society of Nuclear Medicine, as well as over 50 other societies, are members of this group. We are a group of over 700,000 health care professionals in radiology, pediatrics, medical physics and radiation protection. More information can be found ...

  10. OFFSITE ENVIRONMENTAL MONITORING REPORT. RADIATION MONITORING AROUND UNITED STATES NUCLEAR TEST AREAS, CALENDAR YEAR 1982

    EPA Science Inventory

    A principal activity of the Offsite Radiological Safety Program is routine environmental monitoring for radioactive materials in various media and for radiation in areas which may be affected by nuclear tests. It is conducted to document compliance with standards, to identify tre...

  11. Inactivation of nuclear polyhedrosis virus (Baculovirus subgroup A) by monochromatic UV radiation

    SciTech Connect

    Griego, V.M.; Martignoni, M.E.; Claycomb, A.E.

    1985-03-01

    Monochromatic radiation at wavelengths of 290, 300, 310, and 320 nm inactivated occluded nuclear polyhedrosis virus of the Douglas-fir tussock moth, Orgyia pseudotsugata. Data indicate that all of the wavelengths are capable of causing virus inactivation; much greater fluences are needed for virus inactivation as the wavelength increases.

  12. Science, Society, and America's Nuclear Waste: Ionizing Radiation, Unit 2. Teacher Guide. Second Edition.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC. Office of Civilian Radioactive Waste Management, Washington, DC.

    This guide is Unit 2 of the four-part series, Science, Society, and America's Nuclear Waste, produced by the U.S. Department of Energy's Office of Civilian Radioactive Waste Management. The goal of this unit is to convey factual information relevant to radioactivity and radiation and relate that information both to the personal lives of students…

  13. Determination of Important Nuclear Fragmentation Processes for Human Space Radiation Protection

    NASA Technical Reports Server (NTRS)

    Lin, Zi-Wei

    2007-01-01

    We present a semi-analytical method to determine which partial cross sections of nuclear fragmentations most affect the shielded dose equivalent due to exposure to galactic cosmic rays. The cross sections thus determined will require more theoretical and/or experimental studies in order for us to better predict, reduce and mitigate the radiation exposure in human space explorations.

  14. Radiation fields and dose assessments in Korean nuclear power plants.

    PubMed

    Kim, Hee Geun; Kong, Tae Young; Jeong, Woo Tae; Kim, Seok Tae

    2011-07-01

    In the primary systems of nuclear power plants (NPPs), various radionuclides including fission products and corrosion products are generated due to the complex water chemistry conditions. In particular, (3)H, (14)C, (58)Co, (60)Co, (137)Cs, and (131)I are important or potential radionuclides with respect to dose assessment for workers and the management of radioactive effluents or dose assessment for the public. In this paper, the dominant contributors to the dose for workers and the public were reviewed and the process of dose assessment attributable to those contributors was investigated. Furthermore, an analysis was carried out on some examples of dose to workers during NPP operation. PMID:21498858

  15. [Radiation-related health effects of major nuclear events].

    PubMed

    Orgiazzi, Jacques

    2015-01-01

    Three major nuclear events, the Hirosima and Nagasaki bombings and the Chernobyl and Fukushima catastrophes, have been selected to Illustrate the health consequences, observed or anticipated, of irradation of populations. Differences in doses and modalities of irradiation, with the combination of clinical epidemiology and dose estimates, recently revisited, allow for more accurate dose-effect relationship models of the risks. However, extrapolation to the low-doses (< 0.1 Gy) or very low-doses of these models obtained with doses ≥ 0.2 Gy remains hazardous. PMID:25842445

  16. Radiation exposure control from the application of nuclear gauges in the mining industry in Ghana.

    PubMed

    Faanu, A; Darko, E O; Awudu, A R; Schandorf, C; Emi-Reynolds, G; Yeboah, J; Glover, E T; Kattah, V K

    2010-05-01

    The use of nuclear gauges for process control and elemental analysis in the mining industry in Ghana, West Africa, is wide spread and on the increase in recent times. The Ghana Radiation Protection Board regulates nuclear gauges through a system of notification and authorization by registration or licensing, inspection, and enforcement. Safety assessments for authorization and enforcement have been established to ensure the safety and security of radiation sources as well as protection of workers and the general public. Appropriate training of mine staff is part of the efforts to develop the necessary awareness about the safety and security of radiation sources. The knowledge and skills acquired will ensure the required protection and safety at the workplaces. Doses received by workers monitored over a period between 1998 and 2007 are well below the annual dose limit of 20 mSv recommended by the International Commission on Radiological Protection. PMID:20386190

  17. NIAID/NIH radiation/nuclear medical countermeasures product research and development program.

    PubMed

    Hafer, Nathaniel; Cassatt, David; Dicarlo, Andrea; Ramakrishnan, Narayani; Kaminski, Joseph; Norman, Mai-Kim; Maidment, Bert; Hatchett, Richard

    2010-06-01

    One of the greatest national security threats to the United States is the detonation of an improvised nuclear device or a radiological dispersal device in a heavily populated area. The U.S. Government has addressed these threats with a two-pronged strategy of preventing organizations from obtaining weapons of mass destruction and preparing in case an event occurs. The National Institute of Allergy and Infectious Diseases (NIAID) contributes to these preparedness efforts by supporting basic research and development for chemical, biological, radiological, and nuclear countermeasures for civilian use. The Radiation Countermeasures Program at NIAID has established a broad research agenda focused on the development of new medical products to mitigate and treat acute and long-term radiation injury, promote the clearance of internalized radionuclides, and facilitate accurate individual dose and exposure assessment. This paper reviews the recent work and collaborations supported by the Radiation Countermeasures Program. PMID:20445403

  18. High-intensity power-resolved radiation imaging of an operational nuclear reactor

    NASA Astrophysics Data System (ADS)

    Beaumont, Jonathan S.; Mellor, Matthew P.; Villa, Mario; Joyce, Malcolm J.

    2015-10-01

    Knowledge of the neutron distribution in a nuclear reactor is necessary to ensure the safe and efficient burnup of reactor fuel. Currently these measurements are performed by in-core systems in what are extremely hostile environments and in most reactor accident scenarios it is likely that these systems would be damaged. Here we present a compact and portable radiation imaging system with the ability to image high-intensity fast-neutron and gamma-ray fields simultaneously. This system has been deployed to image radiation fields emitted during the operation of a TRIGA test reactor allowing a spatial visualization of the internal reactor conditions to be obtained. The imaged flux in each case is found to scale linearly with reactor power indicating that this method may be used for power-resolved reactor monitoring and for the assay of ongoing nuclear criticalities in damaged nuclear reactors.

  19. High-intensity power-resolved radiation imaging of an operational nuclear reactor.

    PubMed

    Beaumont, Jonathan S; Mellor, Matthew P; Villa, Mario; Joyce, Malcolm J

    2015-01-01

    Knowledge of the neutron distribution in a nuclear reactor is necessary to ensure the safe and efficient burnup of reactor fuel. Currently these measurements are performed by in-core systems in what are extremely hostile environments and in most reactor accident scenarios it is likely that these systems would be damaged. Here we present a compact and portable radiation imaging system with the ability to image high-intensity fast-neutron and gamma-ray fields simultaneously. This system has been deployed to image radiation fields emitted during the operation of a TRIGA test reactor allowing a spatial visualization of the internal reactor conditions to be obtained. The imaged flux in each case is found to scale linearly with reactor power indicating that this method may be used for power-resolved reactor monitoring and for the assay of ongoing nuclear criticalities in damaged nuclear reactors. PMID:26450669

  20. High-intensity power-resolved radiation imaging of an operational nuclear reactor

    PubMed Central

    Beaumont, Jonathan S.; Mellor, Matthew P.; Villa, Mario; Joyce, Malcolm J.

    2015-01-01

    Knowledge of the neutron distribution in a nuclear reactor is necessary to ensure the safe and efficient burnup of reactor fuel. Currently these measurements are performed by in-core systems in what are extremely hostile environments and in most reactor accident scenarios it is likely that these systems would be damaged. Here we present a compact and portable radiation imaging system with the ability to image high-intensity fast-neutron and gamma-ray fields simultaneously. This system has been deployed to image radiation fields emitted during the operation of a TRIGA test reactor allowing a spatial visualization of the internal reactor conditions to be obtained. The imaged flux in each case is found to scale linearly with reactor power indicating that this method may be used for power-resolved reactor monitoring and for the assay of ongoing nuclear criticalities in damaged nuclear reactors. PMID:26450669

  1. Integrated Radiation Transport and Nuclear Fuel Performance for Assembly-Level Simulations

    SciTech Connect

    Hamilton, Steven P; Clarno, Kevin T; Philip, Bobby; Berrill, Mark A; Sampath, Rahul S; Allu, Srikanth

    2012-01-01

    The Advanced Multi-Physics (AMP) Nuclear Fuel Performance code (AMPFuel) is focused on predicting the temperature and strain within a nuclear fuel assembly to evaluate the performance and safety of existing and advanced nuclear fuel bundles within existing and advanced nuclear reactors. AMPFuel was extended to include an integrated nuclear fuel assembly capability for (one-way) coupled radiation transport and nuclear fuel assembly thermo-mechanics. This capability is the initial step toward incorporating an improved predictive nuclear fuel assembly modeling capability to accurately account for source-terms, such as neutron flux distribution, coolant conditions and assembly mechanical stresses, of traditional (single-pin) nuclear fuel performance simulation. A novel scheme is introduced for transferring the power distribution from the Scale/Denovo (Denovo) radiation transport code (structured, Cartesian mesh with smeared materials within each cell) to AMPFuel (unstructured, hexagonal mesh with a single material within each cell), allowing the use of a relatively coarse spatial mesh (10 million elements) for the radiation transport and a fine spatial mesh (3.3 billion elements) for thermo-mechanics with very little loss of accuracy. With this novel capability, AMPFuel was used to model an entire 1717 pressurized water reactor fuel assembly with many of the features resolved in three dimensions (for thermo-mechanics and/or neutronics). A full assembly calculation was executed on Jaguar using 40,000 cores in under 10 hours to model over 160 billion degrees of freedom for 10 loading steps. The single radiation transport calculation required about 50% of the time required to solve the thermo-mechanics with a single loading step, which demonstrates that it is feasible to incorporate, in a single code, a high-fidelity radiation transport capability with a high-fidelity nuclear fuel thermo-mechanics capability and anticipate acceptable computational requirements. The

  2. Radiation litigation and the nuclear industry--the experience in the United Kingdom.

    PubMed

    Leigh, W J; Wakeford, R

    2001-12-01

    In the United Kingdom, the Nuclear Installations Act 1965 places a "strict" statutory duty on the operators of nuclear facilities to ensure that any exposure to radiation resulting from operations does not cause injury or damage. A claimant does not have to prove fault to receive compensation under the Act, only causation. The 1965 Act has been fundamental in shaping litigation involving the nuclear industry in the UK. Civil law cases brought under the Act will be heard before a single judge (with no jury or technical assessor) who must present his or her decision in a reasoned judgment. This process leads to a considerable volume of expert evidence being presented to the court and extensive cross-examination of witnesses. The expense and uncertain outcome of cases involving claims by nuclear workers that occupational exposure to radiation had caused the development of cancer has led to employers and trade unions setting up the voluntary Compensation Scheme for Radiation-linked Diseases as an alternative to litigation. This Scheme has worked well and is held up as a model of alternative dispute resolution. However, a few cases concerning personal injury or damage to property have come before the courts when the defendant nuclear operator considered that the claims were technically unjustified and where settlement was not a policy option. As anticipated, these cases were lengthy, complex, and expensive. The radiation doses assessed to have been received by the individuals who were the subject of claims, whether workers or members of the public, have been crucial to the outcome. The technical expertise of health physicists and allied specialists has been vital in establishing defensible estimates of dose, and this contribution can be expected to remain of high importance in radiation litigation in the UK. PMID:11725882

  3. Annual Conference on Nuclear and Space Radiation Effects, 19th, Las Vegas, NV, July 20-22, 1982, Proceedings

    NASA Technical Reports Server (NTRS)

    Long, D. M.

    1982-01-01

    The results of research concerning the effects of nuclear and space radiation are presented. Topics discussed include the basic mechanisms of nuclear and space radiation effects, radiation effects in devices, and radiation effects in microcircuits, including studies of radiation-induced paramagnetic defects in MOS structures, silicon solar cell damage from electrical overstress, radiation-induced charge dynamics in dielectrics, and the enhanced radiation effects on submicron narrow-channel NMOS. Also examined are topics in SGEMP/IEMP phenomena, hardness assurance and testing, energy deposition, desometry, and radiation transport, and single event phenomena. Among others, studies are presented concerning the limits to hardening electronic boxes to IEMP coupling, transient radiation screening of silicon devices using backside laser irradiation, the damage equivalence of electrons, protons, and gamma rays in MOS devices, and the single event upset sensitivity of low power Schottky devices.

  4. Characterisation of radiation field for irradiation of biological samples at nuclear reactor-comparison of twin detector and recombination methods.

    PubMed

    Golnik, N; Gryziński, M A; Kowalska, M; Meronka, K; Tulik, P

    2014-10-01

    Central Laboratory for Radiological Protection is involved in achieving scientific project on biological dosimetry. The project includes irradiation of blood samples in radiation fields of nuclear reactor. A simple facility for irradiation of biological samples has been prepared at horizontal channel of the nuclear reactor MARIA in NCBJ in Poland. The radiation field, composed mainly of gamma radiation and thermal neutrons, has been characterised in terms of tissue kerma using twin-detector technique and recombination chambers. PMID:24366246

  5. Solid state nuclear radiation detector circuit with constant sensitivity

    SciTech Connect

    Kronenberg, S.; Lux, R. A.

    1985-07-02

    This circuit comprises a solid state crystal radiation counter having its amplified output connected in parallel to a pair of pulse height discriminators with thresholds of V/sub 1/ and 2V/sub 1/ volts, wherein V/sub 1/ is above the counter noise level. A pair of pulse counters are arranged to count the outputs of the discriminators and a processor circuit is connected to the pulse counter outputs and is arranged to calculate the quotient of the square of the output of the pulse counter connected to the discriminator with the lower threshold and the output of the other pulse counter. A display circuit is arranged to provide a reading related to the output of the processor circuit.

  6. Solid state nuclear radiation detector circuit with constant sensitivity

    SciTech Connect

    Kronenberg, S.; Lux, R.A.

    1984-02-06

    This circuit comprises a solid state crystal radiation counter having its amplified output connected in parallel to a pair of pulse height discriminators with thresholds of V sub 1 and V sub 1 volts. Wherein V sub 1 is above the counter noise level. A pair of pulse counters are arranged to count the outputs of the discriminators and a processor circuit is connected to the pulse counter outputs and is arranged to calculate the quotient of the square of the output of the pulse counter connected to the discriminator with the lower threshold and the output of the other pulse counter. A display circuit is arranged to provide a reading related to the output of the processor circuit.

  7. Analysis of Nuclear Reactor Background Radiation for Neutrino Experiments

    NASA Astrophysics Data System (ADS)

    Leblanc, Ricky; Blackmon, J. C.; Rasco, B. C.; Mumm, H. P.; mTC; NuLat Collaboration

    2015-10-01

    Prior measurements of reactor antineutrinos have found a lower flux than expected. Precision measurements of antineutrino energy spectra are important for understanding the anomaly, reactor safeguards, and nuclear nonproliferation. Antineutrino detector designs rely on good characterization of gamma-ray and neutron backgrounds near the reactor core. To study the gamma-ray background at the NIST research reactor, spectra were collected using a 6.25 cm diameter × 5.5 cm germanium detector. We analyzed the measured spectra using simulations of the detector response using the GEANT4 toolkit to determine background fluxes and build a background model that will be used to understand shielding requirements and the impact of backgrounds on potential short-baseline reactor antineutrino studies at NIST. This work supported by the National Science Foundation and LSU.

  8. Constant sensitivity circuit for solid state nuclear radiation counters

    SciTech Connect

    Kronenberg, S.; Erkkila, B.

    1985-02-01

    The utilization of solid state counters in tactical radiological instruments for measuring intensities and doses of fallout gamma rays offers advantages over Geiger-Mueller (GM) counters such as a much wider dynamic range and low operating voltages. Their very small size is suitable for use in miniaturized equipment. However, these devices have a serious problem if used in a mixed, fast neutron/gamma environment such as is encountered e.g. in a battlefield where tactical nuclear weapons are used and neutrons, prompt, initial gammas and fallout gammas are killing factors of comparable importance. Exposure to fast neutrons reduces seriously their sensitivity. This makes the solid state counters at this time unacceptable for use in Army tactical surveillance equipment and in other applications where according to requirements the performance must not be impaired by exposure to fast neutrons. It seems to be possible to reduce to some extent this neutron generated damage by improving the crystal counters.

  9. Radiation Injury Treatment Network (RITN): Healthcare professionals preparing for a mass casualty radiological or nuclear incident

    PubMed Central

    ROSS, JOEL R.; CASE, CULLEN; CONFER, DENNIS; WEISDORF, DANIEL J.; WEINSTOCK, DAVID; KRAWISZ, ROBERT; CHUTE, JOHN; WILHAUK, JULIE; NAVARRO, WILLIS; HARTZMAN, ROBERT; COLEMAN, C. NORMAN; HATCHETT, RICHARD; CHAO, NELSON

    2011-01-01

    Purpose To describe the history, composition, and activities of the Radiation Injury Treatment Network (RITN). The Radiation Injury Treatment Network® is a cooperative effort of the National Marrow Donor Program and the American Society for Blood and Marrow Transplantation. The goals of RITN are to educate hematologists, oncologists, and stem cell transplant practitioners about their potential involvement in the response to a radiation incident and provide treatment expertise. Injuries to the marrow system readily occur when a victim is exposed to ionising radiation. This focus therefore leverages the expertise of these specialists who are accustomed to providing the intensive supportive care required by patients with a suppressed marrow function. Following a radiological incident, RITN centres may be asked to: Accept patient transfers to their institutions; provide treatment expertise to practitioners caring for victims at other centres; travel to other centres to provide medical expertise; or provide data on victims treated at their centres. Moving forward, it is crucial that we develop a coordinated interdisciplinary approach in planning for and responding to radiological and nuclear incidents. The ongoing efforts of radiation biologists, radiation oncologists, and health physicists can and should complement the efforts of RITN and government agencies. Conclusion RITN serves as a vital partner in preparedness and response efforts for potential radiological and nuclear incidents. PMID:21801106

  10. Radiation accidents and their management: emphasis on the role of nuclear medicine professionals

    PubMed Central

    Novruzov, Fuad; Vinjamuri, Sobhan

    2014-01-01

    Large-scale radiation accidents are few in number, but those that have occurred have subsequently led to strict regulation in most countries. Here, different accident scenarios involving exposure to radiation have been reviewed. A triage of injured persons has been summarized and guidance on management has been provided in accordance with the early symptoms. Types of casualty to be expected in atomic blasts have been discussed. Management at the scene of an accident has been described, with explanation of the role of the radiation protection officer, the nature of contaminants, and monitoring for surface contamination. Methods for early diagnosis of radiation injuries have been then described. The need for individualization of treatment according to the nature and grade of the combined injuries has been emphasized, and different approaches to the treatment of internal contamination have been presented. The role of nuclear medicine professionals, including physicians and physicists, has been reviewed. It has been concluded that the management of radiation accidents is a very challenging process and that nuclear medicine physicians have to be well organized in order to deliver suitable management in any type of radiation accident. PMID:25004166

  11. Summary Report for the Radiation Detection for Nuclear Security Summer School 2014

    SciTech Connect

    Runkle, Robert C.; Baciak, James E.; Woodring, Mitchell L.; Jenno, Diana M.

    2014-09-30

    Executive Summary The Pacific Northwest National Laboratory (PNNL) hosted students from across the United States at the 3rd Radiation Detection for Nuclear Security Summer School from 16 – 27 June 2014. The summer school provided students with a unique understanding of nuclear security challenges faced in the field and exposed them to the technical foundations, analyses, and insight that will be required by future leaders in technology development and implementation. The course heavily emphasized laboratory and field demonstrations including direct measurements of special nuclear material. Student evaluations and feedback from student advisors indicates that the summer school achieved its objectives of 1) exposing students to the range of nuclear security applications for which radiation detection is necessary, 2) articulating the relevance of student research into the broader context, and 3) exciting students about the possibility of future careers in nuclear security. In fact, we are beginning to see previous students both enroll in graduate programs (former undergraduates) and complete internships at agencies like the National Nuclear Security Administration.

  12. What Becomes of Nuclear Risk Assessment in Light of Radiation Hormesis?

    PubMed Central

    Cuttler, Jerry M.

    2007-01-01

    A nuclear probabilistic risk or safety assessment (PRA or PSA) is a scientific calculation that uses assumptions and models to determine the likelihood of plant or fuel repository failures and the corresponding releases of radioactivity. Estimated radiation doses to the surrounding population are linked inappropriately to risks of cancer death and congenital malformations. Even though PRAs use very pessimistic assumptions, they demonstrate that nuclear power plants and fuel repositories are very safe compared with the health risks of other generating options or other risks that people readily accept. Because of the frightening negative images and the exaggerated safety and health concerns that are communicated, many people judge nuclear risks to be unacceptable and do not favour nuclear plants. Large-scale tests and experience with nuclear accidents demonstrate that even severe accidents expose the public to only low doses of radiation, and a century of research has demonstrated that such exposures are beneficial to health. A scientific basis for this phenomenon now exists. PRAs are valuable tools for improving plant designs, but if nuclear power is to play a significant role in meeting future energy needs, we must communicate its many real benefits and dispel the negative images formed by unscientific extrapolations of harmful effects at high doses. PMID:18648610

  13. What becomes of nuclear risk assessment in light of radiation hormesis?

    PubMed

    Cuttler, Jerry M

    2007-01-01

    A nuclear probabilistic risk or safety assessment (PRA or PSA) is a scientific calculation that uses assumptions and models to determine the likelihood of plant or fuel repository failures and the corresponding releases of radioactivity. Estimated radiation doses to the surrounding population are linked inappropriately to risks of cancer death and congenital malformations. Even though PRAs use very pessimistic assumptions, they demonstrate that nuclear power plants and fuel repositories are very safe compared with the health risks of other generating options or other risks that people readily accept. Because of the frightening negative images and the exaggerated safety and health concerns that are communicated, many people judge nuclear risks to be unacceptable and do not favour nuclear plants. Large-scale tests and experience with nuclear accidents demonstrate that even severe accidents expose the public to only low doses of radiation, and a century of research has demonstrated that such exposures are beneficial to health. A scientific basis for this phenomenon now exists. PRAs are valuable tools for improving plant designs, but if nuclear power is to play a significant role in meeting future energy needs, we must communicate its many real benefits and dispel the negative images formed by unscientific extrapolations of harmful effects at high doses. PMID:18648610

  14. 1988 IEEE Annual Conference on Nuclear and Space Radiation Effects, 25th, Portland, OR, July 12-15, 1988, Proceedings

    NASA Technical Reports Server (NTRS)

    Coakley, Peter G. (Editor)

    1988-01-01

    The effects of nuclear and space radiation on the performance of electronic devices are discussed in reviews and reports of recent investigations. Topics addressed include the basic mechanisms of radiation effects, dosimetry and energy-dependent effects, sensors in and for radiation environments, EMP/SGEMP/IEMP phenomena, radiation effects on isolation technologies, and spacecraft charging and space radiation effects. Consideration is given to device radiation effects and hardening, hardness assurance and testing techniques, IC radiation effects and hardening, and single-event phenomena.

  15. Radiation sickness

    MedlinePlus

    ... to determine the amount of radiation exposure from nuclear accidents, the best signs of the severity of the ... doses of radiation, such as radiation from a nuclear power plant accident Exposure to excessive radiation for medical treatments

  16. Experimental investigation on radiation shielding of high performance concrete for nuclear and radiotherapy facilities

    NASA Astrophysics Data System (ADS)

    Domański, Szymon; Gryziński, Michał A.; Maciak, Maciej; Murawski, Łukasz; Tulik, Piotr; Tymińska, Katarzyna

    2016-06-01

    This paper presents the set of procedures developed in Radiation Protection Measurements Laboratory at National Centre for Nuclear Research for evaluation of shielding properties of high performance concrete. The purpose of such procedure is to characterize the material behaviour against gamma and neutron radiation. The range of the densities of the concrete specimens was from 2300 to 3900 kg/m3. The shielding properties against photons were evaluated using 137Cs and 60Co sources. The neutron radiation measurements have been performed by measuring the transmitted radiation from 239PuBe source. Scattered neutron radiation has been evaluated using the shadow cone technique. A set up of ionization chambers was used during all experiments. The gamma dose was measured using C-CO2 ionization chamber. The neutron dose was evaluated with recombination chamber of REM-2 type with appropriate recombination method applied. The method to distinguish gamma and neutron absorbed dose components in mixed radiation fields using twin detector method was presented. Also, recombination microdosimetric method was applied for the obtained results. Procedures to establish consecutive half value layers and tenth value layers (HVL and TVL) for gamma and neutron radiation were presented. Measured HVL and TVL values were linked with concrete density to highlight well known dependence. Also, influence of specific admixtures to concrete on neutron attenuation properties was studied. The results confirmed the feasibility of approach for the radiation shielding investigations.

  17. RADIATION HARDNESS / TOLERANCE OF SI SENSORS / DETECTORS FOR NUCLEAR AND HIGH ENERGY PHYSICS EXPERIMENTS.

    SciTech Connect

    LI,Z.

    2002-09-09

    Silicon sensors, widely used in high energy and nuclear physics experiments, suffer severe radiation damage that leads to degradations in sensor performance. These degradations include significant increases in leakage current, bulk resistivity, and space charge concentration. The increase in space charge concentration is particularly damaging since it can significantly increase the sensor full depletion voltage, causing either breakdown if operated at high biases or charge collection loss if operated at lower biases than full depletion. Several strategies can be used to make Si detectors more radiation had tolerant to particle radiations. In this paper, the main radiation induced degradations in Si detectors will be reviewed. The details and specifics of the new engineering strategies: material/impurity/defect engineering (MIDE); device structure engineering (DSE); and device operational mode engineering (DOME) will be given.

  18. Track structure based modelling of light ion radiation effects on nuclear and mitochondrial DNA

    NASA Astrophysics Data System (ADS)

    Schmitt, Elke; Ottolenghi, Andrea; Dingfelder, Michael; Friedland, Werner; Kundrat, Pavel; Baiocco, Giorgio

    2016-07-01

    Space radiation risk assessment is of great importance for manned spaceflights in order to estimate risks and to develop counter-measures to reduce them. Biophysical simulations with PARTRAC can help greatly to improve the understanding of initial biological response to ionizing radiation. Results from modelling radiation quality dependent DNA damage and repair mechanisms up to chromosomal aberrations (e.g. dicentrics) can be used to predict radiation effects depending on the kind of mixed radiation field exposure. Especially dicentric yields can serve as a biomarker for an increased risk due to radiation and hence as an indicator for the effectiveness of the used shielding. PARTRAC [1] is a multi-scale biophysical research MC code for track structure based initial DNA damage and damage response modelling. It integrates physics, radiochemistry, detailed nuclear DNA structure and molecular biology of DNA repair by NHEJ-pathway to assess radiation effects on cellular level [2]. Ongoing experiments with quasi-homogeneously distributed compared to sub-micrometre focused bunches of protons, lithium and carbon ions allow a separation of effects due to DNA damage complexity on nanometre scale from damage clustering on (sub-) micrometre scale [3, 4]. These data provide an unprecedented benchmark for the DNA damage response model in PARTRAC and help understand the mechanisms leading to cell killing and chromosomal aberrations (e.g. dicentrics) induction. A large part of space radiation is due to a mixed ion field of high energy protons and few heavier ions that can be only partly absorbed by the shielding. Radiation damage induced by low-energy ions significantly contributes to the high relative biological efficiency (RBE) of ion beams around Bragg peak regions. For slow light ions the physical cross section data basis in PARTRAC has been extended to investigate radiation quality effects in the Bragg peak region [5]. The resulting range and LET values agree with ICRU data

  19. Advances in nuclear data and all-particle transport for radiation oncology

    SciTech Connect

    White, R.M.; Chadwick, M.B.; Chandler, W.P.; Hartmann Siantar, C.L.; Westbrook, C.K.

    1994-05-01

    Fast neutrons have been used to treat over 15,000 cancer patients worldwide and proton therapy is rapidly emerging as a treatment of choice for tumors around critical anatomical structures. Neutron therapy requires evaluated data to {approximately}70 MeV while proton therapy requires data to {approximately}250 MeV. Collaboration between Lawrence Livermore National Laboratory (LLNL) and the medical physics community has revealed limitations in nuclear cross section evaluations and radiation transport capabilities that have prevented neutron and proton radiation therapy centers from using Monte Carlo calculations to accurately predict dose in patients. These evaluations require energy- and angle-dependent cross sections for secondary neutrons, charged-particles and recoil nuclei. We are expanding the LLNL nuclear databases to higher energies for biologically important elements and have developed a three-dimensional, all-particle Monte Carlo radiation transport code that uses computer-assisted-tomography (CT) images as the input mesh. This code, called PEREGRINE calculates dose distributions in the human body and can be used as a tool to determine the dependence of dose on details of the evaluated nuclear data. In this paper, we will review the status of the nuclear data required for neutron and proton therapy, describe the capabilities of the PEREGRINE package, and show the effects of tissue inhomogeneities on dose distribution.

  20. How Space Radiation Risk from Galactic Cosmic Rays at the International Space Station Relates to Nuclear Cross Sections

    NASA Technical Reports Server (NTRS)

    Lin, Zi-Wei; Adams, J. H., Jr.

    2005-01-01

    Space radiation risk to astronauts is a major obstacle for long term human space explorations. Space radiation transport codes have thus been developed to evaluate radiation effects at the International Space Station (ISS) and in missions to the Moon or Mars. We study how nuclear fragmentation processes in such radiation transport affect predictions on the radiation risk from galactic cosmic rays. Taking into account effects of the geomagnetic field on the cosmic ray spectra, we investigate the effects of fragmentation cross sections at different energies on the radiation risk (represented by dose-equivalent) from galactic cosmic rays behind typical spacecraft materials. These results tell us how the radiation risk at the ISS is related to nuclear cross sections at different energies, and consequently how to most efficiently reduce the physical uncertainty in our predictions on the radiation risk at the ISS.

  1. A Statistical Model for Generating a Population of Unclassified Objects and Radiation Signatures Spanning Nuclear Threats

    SciTech Connect

    Nelson, K; Sokkappa, P

    2008-10-29

    This report describes an approach for generating a simulated population of plausible nuclear threat radiation signatures spanning a range of variability that could be encountered by radiation detection systems. In this approach, we develop a statistical model for generating random instances of smuggled nuclear material. The model is based on physics principles and bounding cases rather than on intelligence information or actual threat device designs. For this initial stage of work, we focus on random models using fissile material and do not address scenarios using non-fissile materials. The model has several uses. It may be used as a component in a radiation detection system performance simulation to generate threat samples for injection studies. It may also be used to generate a threat population to be used for training classification algorithms. In addition, we intend to use this model to generate an unclassified 'benchmark' threat population that can be openly shared with other organizations, including vendors, for use in radiation detection systems performance studies and algorithm development and evaluation activities. We assume that a quantity of fissile material is being smuggled into the country for final assembly and that shielding may have been placed around the fissile material. In terms of radiation signature, a nuclear weapon is basically a quantity of fissile material surrounded by various layers of shielding. Thus, our model of smuggled material is expected to span the space of potential nuclear weapon signatures as well. For computational efficiency, we use a generic 1-dimensional spherical model consisting of a fissile material core surrounded by various layers of shielding. The shielding layers and their configuration are defined such that the model can represent the potential range of attenuation and scattering that might occur. The materials in each layer and the associated parameters are selected from probability distributions that span the

  2. Advances in Nuclear Cardiac Instrumentation with a View Towards Reduced Radiation Exposure

    PubMed Central

    Dey, Damini; Duvall, W. Lane; Henzlova, Milena J.; Berman, Daniel S.; Germano, Guido

    2013-01-01

    Recent advances in nuclear cardiology instrumentation have enabled myocardial perfusion imaging (MPI) with improved image quality and fast scan times. These developments also can be exploited to reduce the effective radiation dose to the patient. In this review, we discuss these technologies including new single photon emission computed tomography (SPECT) and positron emission tomography (PET) scanners, as well as novel reconstruction software with regard to their potential for the reduction of the patient radiation dose. New advances in nuclear cardiology instrumentation will allow routine rest/stress MPI imaging with low radiation doses (< 5 mSv) and fast imaging times, even by the software-only solutions. It is possible to further reduce the MPI radiation dose to less than 2 to 3 mSv range with standard acquisition times. PET perfusion imaging also can be performed with very low doses especially by the three-dimensional scanners allowing hybrid PET/computed tomographic angiography (CTA) imaging with low overall dose. In addition, stress-only protocols can be utilized to further reduce the radiation dose and the overall test time. PMID:22327929

  3. Radiation safety review for 511-keV emitters in nuclear medicine.

    PubMed

    Dell, M A

    1997-03-01

    With the advent of high-energy collimators and dual-head coincidence cameras, standard nuclear medicine facilities will soon begin imaging with PET isotopes. The use of 511-keV emitters raises new radiation safety concerns for technologists traditionally limited to handling 99mTc and other low-energy isotopes. This article is a basic review of positron emitters, measurement concerns, exposure rates, shielding requirements and external radiation exposure mitigation. Newly developed PET shielding products are presented and regulatory status is discussed briefly. PMID:9239598

  4. Depletion calculations for the McClellan Nuclear Radiation Center.

    SciTech Connect

    Klann, R. T.; Newell, D. L.

    1997-12-08

    Depletion calculations have been performed for the McClellan reactor history from January 1990 through August 1996. A database has been generated for continuing use by operations personnel which contains the isotopic inventory for all fuel elements and fuel-followed control rods maintained at McClellan. The calculations are based on the three-dimensional diffusion theory code REBUS-3 which is available through the Radiation Safety Information Computational Center (RSICC). Burnup-dependent cross-sections were developed at zero power temperatures and full power temperatures using the WIMS code (also available through RSICC). WIMS is based on discretized transport theory to calculate the neutron flux as a function of energy and position in a one-dimensional cell. Based on the initial depletion calculations, a method was developed to allow operations personnel to perform depletion calculations and update the database with a minimal amount of effort. Depletion estimates and calculations can be performed by simply entering the core loading configuration, the position of the control rods at the start and end of cycle, the reactor power level, the duration of the reactor cycle, and the time since the last reactor cycle. The depletion and buildup of isotopes of interest (heavy metal isotopes, erbium isotopes, and fission product poisons) are calculated for all fuel elements and fuel-followed control rods in the MNRC inventory. The reactivity loss from burnup and buildup of fission product poisons and the peak xenon buildup after shutdown are also calculated. The reactivity loss from going from cold zero power to hot full power can also be calculated by using the temperature-dependent, burnup-dependent cross-sections. By calculating all of these reactivity effects, operations personnel are able to estimate the total excess reactivity necessary to run the reactor for the given cycle. This method has also been used to estimate the worth of individual control rods. Using this

  5. A brief review of intermediate controlled nuclear syntheses (ICNS) without harmful radiations

    SciTech Connect

    Lanjewar, R. B.

    2015-03-10

    Hadronic mechanics gave birth to new magnecular fuels. The present day demand is of clean energy source that is cheap and abundant. Clean energy can be obtained by harnessing renewable energy sources like solar, wind etc. Nuclear energy conventionally produced by fission reactions emits hazardous radiation and radioactive waste. The requirements of clean and safe energy gets fulfilled by novel fuel that achieved by elevating the traditional quantum mechanics to hadronic mechanics and to hadronic chemistry. In the present paper, a comprehensive review on both the theoretical and experimental aspect of the Intermediate Controlled Nuclear Synthesis (ICNS) as developed by Italian American Scientist Professor R. M. Santilli.

  6. Nuclear modeling for applications in medical radiation therapy and accelerator-driven technologies

    SciTech Connect

    Chadwick, M.B.

    1995-06-01

    An understanding of the interactions of neutrons and protons below a few hundred MeV with nuclei is important for a number of applications. In this paper, two new applications are discussed: radiation transport calculations of energy deposition in fast neutron and proton cancer radiotherapy to optimize the dose given to a tumor; and intermediate-energy proton accelerators which are currently being designed for a range of applications including the destruction of long-lived radioactive nuclear waste. We describe nuclear theory calculations of direct, preequilibrium, and compound nucleus reaction mechanisms important for the modeling of these systems.

  7. Coupled radiation transport/thermal analysis of the radiation shield for a space nuclear reactor

    NASA Astrophysics Data System (ADS)

    Barattino, W. J.

    1985-07-01

    A coupled radiation transport-heat transfer-stress analysis of the radiation shield for an SP-100 reactor was performed using a numerical code developed at the University of New Mexico and Sandia National Laboratory. For a fast reactor operating at 1.66 MW sub th, the energy deposited and resulting temperature distribution was determined for a shield consisting of tungsten and lithium hydride pressed into a stainless steel honeycomb matrix. While temperature feedback was shown to have a minor effect on energy deposition, the shielding configuration was found to have a major influence in meeting thermal requirements of the lithium hydride. It was shown that a shield optimized for radiation protection will fail because of melting. However, with minor modifications in the shield layering and material selection, the thermal integrity of the shield can be preserved. A shield design of graphite, depleted lithium hydride, tungsten, and natural lithium hydride was shown to satisfy neutron and gamma fluence requirements, maximum temperature limits, and minimize cracking in the LiH portion of the shield.

  8. Nuclear dynamics of radiation-induced foci in euchromatin and heterochromatin

    SciTech Connect

    Chiolo, Irene; Georgescu, Walter; Tang, Jonathan; Costes, Sylvain V.

    2013-09-03

    Repair of double strand breaks (DSBs) is essential for cell survival and genome integrity. While much is known about the molecular mechanisms involved in DSB repair and checkpoint activation, the roles of nuclear dynamics of radiation-induced foci (RIF) in DNA repair are just beginning to emerge. Here, we summarize results from recent studies that point to distinct features of these dynamics in two different chromatin environments: heterochromatin and euchromatin. We also discuss how nuclear architecture and chromatin components might control these dynamics, and the need of novel quantification methods for a better description and interpretation of these phenomena. These studies are expected to provide new biomarkers for radiation risk and new strategies for cancer detection and treatment.

  9. Graphical user interfaces for McCellan Nuclear Radiation Center (MNRC).

    SciTech Connect

    Brown-VanHoozer, S. A.

    1998-08-27

    McClellan's Nuclear Radiation Center (MNRC) control console is in the process of being replaced due to spurious scrams, outdated software, and obsolete parts. The intent of the new control console is to eliminate the existing problems by installing a UNIX-based computer system with industry-standard interface software and incorporating human factors during all stages of the graphical user interface (GUI) development and control console design.

  10. Intelligent monitor functional model with ionization chamber for mixed nuclear radiation field measurements

    SciTech Connect

    Valcov, N.; Purghel, L.; Celarel, A.

    1998-12-31

    By using the statistical discrimination technique, the components of an ionization current, due to a mixed radiation field, may be simultaneously measured. A functional model, including a series manufactured gamma-ray ratemeter was done, as an intermediate step in the design of specialized nuclear instrumentation, in order to check the concept of statistical discrimination method. The obtained results are in good agreement with the estimations of the statistical discrimination method.

  11. Real-time 3D radiation risk assessment supporting simulation of work in nuclear environments.

    PubMed

    Szőke, I; Louka, M N; Bryntesen, T R; Bratteli, J; Edvardsen, S T; RøEitrheim, K K; Bodor, K

    2014-06-01

    This paper describes the latest developments at the Institute for Energy Technology (IFE) in Norway, in the field of real-time 3D (three-dimensional) radiation risk assessment for the support of work simulation in nuclear environments. 3D computer simulation can greatly facilitate efficient work planning, briefing, and training of workers. It can also support communication within and between work teams, and with advisors, regulators, the media and public, at all the stages of a nuclear installation's lifecycle. Furthermore, it is also a beneficial tool for reviewing current work practices in order to identify possible gaps in procedures, as well as to support the updating of international recommendations, dissemination of experience, and education of the current and future generation of workers.IFE has been involved in research and development into the application of 3D computer simulation and virtual reality (VR) technology to support work in radiological environments in the nuclear sector since the mid 1990s. During this process, two significant software tools have been developed, the VRdose system and the Halden Planner, and a number of publications have been produced to contribute to improving the safety culture in the nuclear industry.This paper describes the radiation risk assessment techniques applied in earlier versions of the VRdose system and the Halden Planner, for visualising radiation fields and calculating dose, and presents new developments towards implementing a flexible and up-to-date dosimetric package in these 3D software tools, based on new developments in the field of radiation protection. The latest versions of these 3D tools are capable of more accurate risk estimation, permit more flexibility via a range of user choices, and are applicable to a wider range of irradiation situations than their predecessors. PMID:24727389

  12. Ab initio simulation of radiation damage in nuclear reactor pressure vessel materials

    NASA Astrophysics Data System (ADS)

    Watts, Daniel; Finkenstadt, Daniel

    2012-02-01

    Using Kinetic Monte Carlo we developed a code to study point defect hopping in BCC metallic alloys using energetics and attempt frequencies calculated using VASP, an electronic structure software package. Our code provides a way of simulating the effects of neutron radiation on potential reactor materials. Specifically we will compare the Molybdenum-Chromium alloy system to steel alloys for use in nuclear reactor pressure vessels.

  13. Impact of the Fukushima nuclear accident on background radiation doses measured by control dosimeters in Japan.

    PubMed

    Romanyukha, Alexander; King, David L; Kennemur, Lisa K

    2012-05-01

    After the 9.0 magnitude earthquake and subsequent massive tsunami on 11 March 2011 in Japan, several reactors at the Fukushima Daiichi Nuclear Power Plant suffered severe damage. There was immediate participation of U.S. Navy vessels and other United States Department of Defense (DoD) teams that were already in the area at the time of the disaster or arrived shortly thereafter. The correct determination of occupational dose equivalent requires estimation of the background dose component measured by control dosimeters, which is subsequently subtracted from the total dose equivalent measured by personal dosimeters. The purpose of the control dosimeters is to determine the amount of radiation dose equivalent that has accumulated on the dosimeter from background or other non-occupational sources while they are in transit or being stored. Given the release of radioactive material and potential exposure to radiation from the Fukushima Daiichi Nuclear Power Plant and the process by which the U.S. Navy calculates occupational exposure to ionizing radiation, analysis of pre- and post-event control dosimeters is warranted. Several hundred historical dose records from the Naval Dosimetry Center (NDC) database were analyzed and compared with the post-accident dose equivalent data of control dosimeters. As result, it was shown that the dose contribution of the radiation and released radiological materials from the Fukushima nuclear accident to background radiation doses is less than 0.375 μSv d for shallow and deep photon dose equivalent. There is no measurable effect on neutron background exposure. The latter has at least two important conclusions. First, the NDC can use doses measured by control dosimeters at issuing sites in Japan for determination of personnel dose equivalents; second, the dose data from control dosimeters prior to and after the Fukushima accident may be used to assist in dose reconstruction of non-radiological (non-badged) personnel at these locations

  14. Health concerns related to radiation exposure of the female nuclear medicine patient.

    PubMed Central

    Stabin, M G

    1997-01-01

    The female nuclear medicine patient is of special concern in evaluating radiation dose and risk in nuclear medicine. The female's overall body size and organ sizes generally are smaller than those of her male counterpart (thus her radiation doses will be higher, given the same amounts of administered activity and similar biokinetics); female gonads are inside the body instead of outside and are near several organs often important as source organs in internal dosimetry (urinary bladder, liver, kidneys, intestines); risk of breast cancer is significantly higher among females than males; and in the case of pregnancy, exposure to radiation of the embryo/fetus and the nursing infant are of special concern in such an analysis. All these concerns are addressed in this study through a comparative study of radiation doses for males and females over a large number (approximately 60) of nuclear medicine studies and through a study of what is known about radiation dosimetry in pregnancy and breast feeding. It was found that women's critical organ doses and effective doses (as defined by the International Commission on Radiological Protection 60 [ICRP 60] are about 25% higher than those for men across all these studies. Women's gonad doses, however, may be as much as 10 to 30 times higher than those in men, although 2- to 3-fold differences are common. Many radiopharmaceuticals are administered to women of childbearing age; however, little is known about how much activity crosses the placenta and about the biokinetics in the fetus should it occur. Nonetheless, dose estimates are provided at four stages of pregnancy (early, 3-month, 6-month, and 9-month gestation) for a large number of radiopharmaceuticals, whether or not quantitative estimates of placental crossover can be made. Many radiopharmaceuticals are also excreted in breast milk of nursing mothers. Breast feeding interruption schedules are suggested through analysis of the observed kinetics of these pharmaceuticals and

  15. Fabric composite radiators for space nuclear power applications. Final report, March 1993

    SciTech Connect

    Klein, A.C.; Al-Baroudi, H.; Gulshan-Ara, Z.; Kiestler, W.C.; Snuggerud, R.D.; Abdul-Hamid, S.A.; Marks, T.S.

    1993-03-24

    Nuclear power systems will be required to provide much greater power levels for both civilian and defense space activities in the future than an currently needed. Limitations on the amount of usable power from radioisotope thermal generators and the limited availability of radioisotope heat source materials lead directly to the conclusion that nuclear power reactors will be needed to enhance the exploration of the solar system as well as to provide for an adequate defense. Lunar bases and travel to the Martian surface will be greatly enhanced by the use of high levels of nuclear power. Space based radar systems requiring many kilowatts of electrical power can provide intercontinental airline traffic control and defense early warning systems. Since the, figure of merit used in defining any space power system is the specific power, the decrease in die mass of any reactor system component will yield a tremendous benefit to the overall system performance. Also, since the heat rejection system of any power system can make up a large portion of the total system mass, any reduction in the mass of the heat rejection radiators will significantly affect the performance of the power system. Composite materials which combine the high strength, flexibility, and low mass characteristics of Si% based fibers with the attractive compatibility and heat transfer features of metallic foils, have been proposed for use m a number of space radiator applications. Thus, the weave of the fabric and the high strength capability of the individual fibers are combined with the high conductivity and chemical stability of a metallic liner to provide a light weight, flexible alternative to heavy, rigid, metallic radiator structural containers. The primary focus of this investigation revolves around two applications of the fabric composite materials, notably a fabric heat pipe radiator design and the Bubble Membrane Radiator concept.

  16. Lightweight Damage Tolerant Radiators for In-Space Nuclear Electric Power and Propulsion

    NASA Technical Reports Server (NTRS)

    Craven, Paul; SanSoucie, Michael P.; Tomboulian, Briana; Rogers, Jan; Hyers, Robert

    2014-01-01

    Nuclear electric propulsion (NEP) is a promising option for high-speed in-space travel due to the high energy density of nuclear power sources and efficient electric thrusters. Advanced power conversion technologies for converting thermal energy from the reactor to electrical energy at high operating temperatures would benefit from lightweight, high temperature radiator materials. Radiator performance dictates power output for nuclear electric propulsion systems. Pitch-based carbon fiber materials have the potential to offer significant improvements in operating temperature and mass. An effort at the NASA Marshall Space Flight Center to show that woven high thermal conductivity carbon fiber mats can be used to replace standard metal and composite radiator fins to dissipate waste heat from NEP systems is ongoing. The goals of this effort are to demonstrate a proof of concept, to show that a significant improvement of specific power (power/mass) can be achieved, and to develop a thermal model with predictive capabilities. A description of this effort is presented.

  17. Impact of an external radiation field on handheld XRF measurements for nuclear forensics applications

    SciTech Connect

    Steeb, Jennifer L.; Mertz, Carol J.; Finck, Martha R.; Engelstad, Gary; Carney, Kevin P.; Chamberlain, David B.

    2015-03-28

    X-ray fluorescence (XRF) is an attractive technique for nuclear forensics applications. We evaluated a handheld, portable XRF device by applying an external radiation field (10 mR/h to 17 R/h) using two types of radiography sources: a 60Co radiography camera to observe effects from high-energy gamma emissions and an 192Ir radiography camera to observe effects from several low-energy gamma (0.604, 0.468, and 0.317 MeV) and decay daughter x-ray emissions. External radiation tests proved that radiation, in general, has a significant effect on the dead time or background at dose rates over 1 R/hr for both the 192Ir and 60Co sources.

  18. Dynamic friction and wear of a solid film lubricant during radiation exposure in a nuclear reactor

    NASA Technical Reports Server (NTRS)

    Jacobson, T. P.

    1972-01-01

    The effect of nuclear reactor radiation on the performance of a solid film lubricant was studied. The film consisted of molybdenum disulfide and graphite in a sodium silicate binder. Radiation levels of fast neutrons (E or = 1 MeV) were fluxed up to 3.5 times 10 to the 12th power n/sq cm-sec (intensity) and fluences up to 2 times 10 to the 18th power n/sq cm (total exposure). Coating wear lives were much shorter and friction coefficients higher in a high flux region of the reactor than in a low flux region. The amount of total exposure did not affect lubrication behavior as severely as the radiation intensity during sliding.

  19. In situ radiation measurements at the former Soviet Nuclear Test Site

    SciTech Connect

    Tipton, W.J.

    1996-06-01

    A team from the Remote Sensing Laboratory conducted a series of in situ radiological measurements at the former Soviet Nuclear Test Site near Semipalatinsk, Kazakhstan, during the period of July 21-30, 1994. The survey team measured the terrestrial gamma radiation at selected areas on the site to determine the levels of natural and man-made radiation. The survey was part of a cooperative effort between the United States team and teams of radiation scientists from the National Nuclear Center of the Republic of Kazakhstan and the V.G. Khlopin Radium Institute in St. Petersburg, Russia. In addition to in situ radiation measurements made by the United States and Russian teams, soil samples were collected and analyzed by the Russian and Kazakhstani teams. All teams conducted their measurements at ten locations within the test site. The United States team also made a number of additional measurements to locate and verify the positions of three potential fallout plumes containing plutonium contamination from nonnuclear tests. In addition, the United States team made several measurements in Kurchatov City, the housing area used by personnel and their families who work(ed) at the test sites. Comparisons between the United States and Russian in situ measurements and the soil sample results are presented as well as comparisons with a Soviet aerial survey conducted in 1990-1991. The agreement between the different types of measurements made by all three countries was quite good.

  20. In vivo mutagenicity and clastogenicity of ionizing radiation in nuclear medicine

    SciTech Connect

    Kelsey, K.T.

    1991-01-01

    The overall goal of our research remains to investigate the mutagenic and clastogenic effects of exposure to low levels of ionizing radiation to human lymphocytes. Principally, we are studying hospital patients referred to a nuclear medicine department for diagnostic cardiac imaging and nuclear medicine technologies who administer radionuclides. Emphasis in the first year, as described in the first progress report, was on optimization of the hprt mutation assay, measurement of mutant frequencies in patients imaged with thallium-201, and measurement of mutant frequencies in controls. Emphasis in the second year has been on measurements of (1) chromosome aberrations in patients imaged with thallium-201, (2) mutant frequencies in patients imaged with technetium-99, (3) mutant frequencies in nuclear medicine technicians and physical therapists, (4) mutant frequencies in patients treated for Hodgkins disease with radiotherapy. The progress in these areas is described.

  1. Offsite environmental monitoring report. Radiation monitoring around United States nuclear test areas, calendar year 1981

    SciTech Connect

    Black, S.C.; Grossman, R.F.; Mullen, A.A.; Potter, G.D.; Smith, D.D.; Hopper, J.L.

    1982-08-01

    This report, prepared in accordance with the guidelines in DOE/E-0023 (DOE 1981), covers the program activities conducted around Nevada Test Site (NTS) for calendar year 1981. It contains descriptions of pertinent features of the NTS and its environs, summaries of the dosimetry and sampling methods, analytical procedures, and the analytical results from environmental measurements. Where applicable, dosimetry and sampling data are compared to appropriate guides for external and internal exposures of humans to ionizing radiation. The monitoring networks detected no radioactivity in the various media which could be attributed to US nuclear testing. Small amounts of fission products were detected in air samples as a result of the People's Republic of China nuclear test and atmospheric krypton-85 increased, following the trend beginning in 1960, due to increased use of nuclear technology. Strontium-90 in milk and cesium-137 in meat samples continued the slow decline as observed for the last several years.

  2. In vivo mutagenicity and clastogenicity of ionizing radiation in nuclear medicine. Annual technical progress report, [1991

    SciTech Connect

    Kelsey, K.T.

    1991-12-31

    The overall goal of our research remains to investigate the mutagenic and clastogenic effects of exposure to low levels of ionizing radiation to human lymphocytes. Principally, we are studying hospital patients referred to a nuclear medicine department for diagnostic cardiac imaging and nuclear medicine technologies who administer radionuclides. Emphasis in the first year, as described in the first progress report, was on optimization of the hprt mutation assay, measurement of mutant frequencies in patients imaged with thallium-201, and measurement of mutant frequencies in controls. Emphasis in the second year has been on measurements of (1) chromosome aberrations in patients imaged with thallium-201, (2) mutant frequencies in patients imaged with technetium-99, (3) mutant frequencies in nuclear medicine technicians and physical therapists, (4) mutant frequencies in patients treated for Hodgkins disease with radiotherapy. The progress in these areas is described.

  3. Legitimating a nuclear critic: John Gofman, radiation safety, and cancer risks.

    PubMed

    Semendeferi, Ioanna

    2008-01-01

    Whether low-level ionizing radiation has an effect on humans has been a polarizing issue for the last fifty years. The epicenter of this controversy has been the validity of the linear non-threshold dose-response model, according to which any amount of radiation, however small, causes damage to human genes and health. In the late 1960s and early 1970s, the nuclear scientist and medical researcher John Gofman (1918-2007) played a pivotal role in the debate. Historical accounts have treated Gofman as a radical antinuclear scientist whose unscientific arguments put enormous political pressure on the nuclear power industry and regulatory agencies. Gofman's bitter struggle with the Atomic Energy Commission, which funded his research at Lawrence Livermore National Laboratory, partly accounts for this view. However, my analysis of Gofman's involvement in the low-level radiation debate shows how he also helped shift the focus in radiation safety from the risks of genetic damage or leukemia to somatic or cancer risks. His arguments led to the introduction of the linear non-threshold radiation model as a means of numerically estimating cancer risks. This was a watershed event in radiation-safety science and politics. Gofman's case sheds light on the process by which a scientist could secure legitimation even when his technical arguments threatened the government's interests. I conclude that it also points to an open issue in the history of antinuclear scientists, or of other politically active scientists or technology critics: treating them as critics should not preclude historians from treating them as scientists. PMID:20073123

  4. Offsite environmental monitoring report; radiation monitoring around United States nuclear test areas, Calendar Year 1996

    SciTech Connect

    Davis, M.G.; Flotard, R.D.; Fontana, C.A.; Huff, P.A.; Maunu, H.K.; Mouck, T.L.; Mullen, A.A.; Sells, M.D.

    1997-08-01

    This report describes the Offsite Radiation Safety Program. This laboratory operated an environmental radiation monitoring program in the region surrounding the Nevada Test Site (NTS) and at former test sites in Alaska, Colorado, Mississippi, Nevada, and New Mexico. The surveillance program is designed to measure levels and trends of radioactivity, if present, in the environment surrounding testing areas to ascertain whether current radiation levels and associated doses to the general public are in compliance with existing radiation protection standards. The surveillance program additionally has the responsibility to take action to protect the health and well being of the public in the event of any accidental release of radioactive contaminants. Offsite levels of radiation and radioactivity are assessed by sampling milk, water, and air; by deploying thermoluminescent dosimeters (TLDs); and using pressurized ionization chambers (PICs). No nuclear weapons testing was conducted in 1996 due to the continuing nuclear test moratorium. During this period, R and IE personnel maintained readiness capability to provide direct monitoring support if testing were to be resumed and ascertained compliance with applicable EPA, DOE, state, and federal regulations and guidelines. Comparison of the measurements and sample analysis results with background levels and with appropriate standards and regulations indicated that there was no airborne radioactivity from diffusion or resuspension detected by the various EPA monitoring networks surrounding the NTS. There was no indication of potential migration of radioactivity to the offsite area through groundwater and no radiation exposure above natural background was received by the offsite population. All evaluated data were consistent with previous data history.

  5. Risk Perception of Radiation Exposure of Villagers Living Near the Semipalatinsk Nuclear Test Site

    NASA Astrophysics Data System (ADS)

    Purvis-Roberts, K. L.

    2006-12-01

    Connecting scientific data to societal needs is particularly important with the complex environmental issues that face us in the near future, such as global warming and natural hazards. Once the scientific data is collected and analyzed, dissemination of the results needs to be communicated to the public in a way that can be easily understood without glossing over the complexity of the issue. An interesting case study derives from the primary nuclear test site for the former Soviet Union, located near the city of Semipalatinsk, Kazakhstan. Villagers living directly adjacent to the Semipalatinsk Nuclear Test Site (SNTS) were exposed continuously to radioactive clouds from atmospheric, above ground and underground nuclear tests. The people living in the region are still exposed to low levels of radiation through the environmental contamination of their food and water and have experienced a higher incidence of cancers and birth defects than people living in other regions of the country. A database of historical environmental data was collected throughout the nuclear testing period by the Soviet government, tracking radiation concentrations through food, water, and soil samples around the SNTS, but this environmental data was never shared with the villagers. In fact, only after the Soviet Union fell apart in 1989 did the people discover that they had been exposed to radiation during the past 40 years. Through preliminary interviews with villagers, physicians, and scientists who live near the SNTS, it was discovered that the three groups viewed the risk of radiation exposure very differently. By developing a risk perception survey to understand how the different groups perceived radiation risk, and then comparing the scientific data to the survey results, a better way to communicate the risk could be developed. The risk perception survey was given to over 800 people in East Kazakhstan Oblast, including villagers living near the SNTS, scientists who study the

  6. Evidence of children's vulnerability to radiation in the context of radiological/nuclear events and considerations for emergency response.

    PubMed

    Lane, Rachel; Reinhardt, Pascale; Thompson, Patsy

    2010-11-01

    International organisations, such as International Atomic Energy Agency, United Nations Scientific Committee on the Effects of Atomic Radiation and World Health Organisation, together with committees of experts such as Biological Effects of Ionising Radiation and Committee on Medical Aspects of Radiation in the Environment, have assessed the effects of radiation on large exposed populations (Chernobyl accident, and Hiroshima/Nagasaki atomic bombings) and on nuclear energy workers and people living near nuclear facilities. Childhood and in utero exposure to moderate and high levels of ionizing radiation, such as those experienced during the atomic bombings of Japan, or from radiotherapy, is an established cause of leukaemia and solid cancer. There is no evidence of increase in solid cancers (excluding thyroid cancer) or leukaemia in the children from Chernobyl, and no evident link between worker's exposure to radiation and leukaemia in their offspring or with the presence of leukaemia clusters around nuclear power plants. It has also not been possible to demonstrate the evidence of radiation hereditary effects in human populations. In accordance with international guidance, Canadian Nuclear Safety Commission recommends optimisation of protection strategies to reduce doses to children. The development of credible radiological/nuclear event scenarios would assist in identifying probable sources of radioactivity and pathways of exposure for children. Such scenarios should then be used to identify protection strategies appropriate for children. PMID:20959331

  7. Radiation dose distribution for workers in South Korean nuclear power plants.

    PubMed

    Lee, Byoung-il; Kim, So-i; Suh, Dong-hee; Jin, Young-woo; Kim, Jeong-in; Choi, Hoon; Lim, Young-khi

    2010-07-01

    A total of 33 680 nuclear power plants (NPPs) workers were monitored and recorded from 1990 to 2007. According to the record, the average individual radiation dose has been decreasing continually from 3.20 mSv man(-1) in 1990 to 1.12 mSv man(-1) at the end of 2007. After the International Commission on Radiological Protection 60 recommendation was generalised in South Korea, no NPP workers received >20 mSv radiation, and the numbers of relatively highly exposed workers have been decreasing continuously. The age distribution of radiation workers in NPPs was composed mainly of 20-30 y olds (83 %) for 1990-1994 and 30-40 y olds (75 %) for 2003-2007. The difference in individual average dose by age was not significant. Most (77 %) of the NPP radiation exposures from 1990 to 2007 occurred mostly during the refueling period. With regard to exposure type, the majority of exposures was external exposures, representing 95 % of the total exposures, whereas internal exposures represented only 5 %. External effective dose was affected mainly by gamma radiation exposure, with an insignificant amount of neutron exposure. As for internal effective dose, tritium in the pressurised heavy water reactor was the biggest cause of exposure. PMID:20223854

  8. Nuclear radiation test of a D flip-flop IC using a single-board microcomputer

    SciTech Connect

    Lim, T.S.; Martin, R.L.; Hughes, H.L.

    1987-01-01

    The design of a microcomputer-controlled electronic circuit and its use in evaluating the effects of nuclear radiation on a 4013 CMOS D flip-flop (FF) integrated circuit (IC) are described. The IC undergoing testing is attached to a DUT (device under test) board, which is enclosed in a metal container. The container is then lowered to the cobalt 60 radiation source located at the bottom of a 15-ft-deep pool filled to the top with water. The gamma-ray radiation test setup is schematically shown. The in-source test board containing the D FF IC is attached to an 8085-based single-board microcomputer, SDK-85, by a 30-ft multiconductor cable. Doses of gamma-ray radiation from the cobalt 60 are applied in steps at increasing quantities until the D FF IC, which is tested between doses, begins to malfunction. The leakage current and the propagation delay time are measured between doses. An 8085 assembly language program is used for functional test of the IC. The software design and the radiation testing procedure are discussed in detail.

  9. Simulation of beta radiator handling procedures in nuclear medicine by means of a movable hand phantom.

    PubMed

    Blunck, Ch; Becker, F; Urban, M

    2011-03-01

    In nuclear medicine therapies, people working with beta radiators such as (90)Y may be exposed to non-negligible partial body doses. For radiation protection, it is important to know the characteristics of the radiation field and possible dose exposures at relevant positions in the working area. Besides extensive measurements, simulations can provide these data. For this purpose, a movable hand phantom for Monte Carlo simulations was developed. Specific beta radiator handling scenarios can be modelled interactively with forward kinematics or automatically with an inverse kinematics procedure. As a first investigation, the dose distribution on a medical doctor's hand injecting a (90)Y solution was measured and simulated with the phantom. Modelling was done with the interactive method based on five consecutive frames from a video recorded during the injection. Owing to the use of only one camera, not each detail of the radiation scenario is visible in the video. In spite of systematic uncertainties, the measured and simulated dose values are in good agreement. PMID:21044994

  10. Twinning in the offspring of parents with chronic radiation exposure from nuclear testing in Kazakhstan.

    PubMed

    Mudie, Nadejda Y; Swerdlow, Anthony J; Gusev, Boris I; Schoemaker, Minouk J; Pivina, Ludmila M; Chsherbakova, Svetlana; Mansarina, Almagul; Bauer, Susanne; Jakovlev, Yuri; Apsalikov, Kazbek N

    2010-06-01

    The population of the Semipalatinsk region of Kazakhstan was chronically exposed to radioactive fallout from above-ground nuclear tests conducted during 1949-1956 by the Soviet Union. We investigated the effect of radiation exposure and other factors on risks of twinning overall and of same- and different-sex twinning and hence estimated dizygotic and monozygotic twinning rates in 11,605 deliveries around Semipalatinsk, 141 of which were twin, to 3992 mothers exposed to fallout during 1949-1956. Overall, the same-sex twinning rate was 7.85 [95% confidence interval (CI): 6.24, 9.47] per 1000 and the opposite-sex twinning rate was 4.45 (95% CI: 3.23, 5.67). Twinning rates did not differ significantly between radiation exposure categories, parental age at main radiation exposure, or year of birth. Different-sex, but not same-sex, twinning increased with maternal age (P(trend) = 0.04) but not with other demographic factors and was increased soon after radiation exposure [OR = 4.08 (95% CI: 1.11, 15.07)] for births occurring within 5 years compared with more than 20 years after exposure; this effect was similar in villages with low and high radiation exposure, however, so interpretation is uncertain. PMID:20518662