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Sample records for leo radiation environment

  1. Operation of commercial R3000 processors in the Low Earth Orbit (LEO) space environment

    Energy Technology Data Exchange (ETDEWEB)

    Kaschmitter, J.L.; Shaeffer, D.L.; Colella, N.J. [Lawrence Livermore National Lab., CA (United States); McKnett, C.L.; Coakley, P.G. [JAYCOR, Santa Monica, CA (United States)

    1990-08-09

    Spacecraft processors must operate with minimal degradation of performance in the Low Earth Orbit (LEO) radiation environment, which includes the effects of total accumulated ionizing dose and Single Event Phenomena (SEP) caused by protons and cosmic rays. Commercially available microprocessors can offer a number of advantages relative to radiation-hardened devices, including lower cost, reduced development and procurement time, extensive software support, higher density and performance. However, commercially available systems are not normally designed to tolerate effects induced by the LEO environment. Lawrence Livermore National Laboratory (LLNL) and others have extensively tested the MIPS R3000 Reduced Instruction Set Computer (RISC) microprocessor family for operation in LEO environments. We have characterized total dose and SEP effects for altitudes and inclinations of interest to systems operating in LEO, and we postulate techniques for detection and alleviation of SEP effects based on experimental results. 12 refs.

  2. Operation of commercial R3000 processors in the low earth orbit (LEO) space environment

    Energy Technology Data Exchange (ETDEWEB)

    Kaschmitter, J.L.; Shaeffer, D.L.; Colella, N.J. (Lawrence Livermore National Lab., CA (United States)); McKnett, C.L.; Coakley, P.G. (JAYCOR, Santa Monica, CA (United States))

    1991-12-01

    Spacecraft processors must operate with minimal degradation of performance in the Low Earth Orbit (LEO) radiation environment, which includes the effects of total accumulated ionizing dose and Single Event Phenomena (SEP) caused by protons and cosmic rays. Commercially available microprocessors can offer a number of advantages relative to radiation-hardened devices, including lower cost, reduced development and procurement time, extensive software support, higher density and performance. However, commercially available systems are not normally designed to tolerate effects induced by the LEO environments. Lawrence Livermore National Laboratory (LLNL) and others have extensively tested the MIPS R3000 Reduced Instruction Set Computer (RISC) microprocessor family for operation in LEO environments. In this paper the authors characterize total dose and SEP effects for altitudes and inclinations of interest to systems operating in LEO, and the authors postulate techniques for detection and alleviation of SEP effects based on experimental results.

  3. Time Serial Analysis of the Induced LEO Environment within the ISS 6A

    Science.gov (United States)

    Wilson, John W.; Nealy, John E.; Tomov, B. T.; Cucinotta, Francis A.; Badavi, Frank F.; DeAngelis, Giovanni; Atwell, William; Leutke, N.

    2006-01-01

    Anisotropies in the low Earth orbit (LEO) radiation environment were found to influence the thermoluminescence detectors (TLD) dose within the (International Space Station) ISS 7A Service Module. Subsequently, anisotropic environmental models with improved dynamic time extrapolation have been developed including westward and northern drifts using AP8 Min & Max as estimates of the historic spatial distribution of trapped protons in the 1965 and 1970 era, respectively. In addition, a directional dependent geomagnetic cutoff model was derived for geomagnetic field configurations from the 1945 to 2020 time frame. A dynamic neutron albedo model based on our atmospheric radiation studies has likewise been required to explain LEO neutron measurements. The simultaneous measurements of dose and dose rate using four Liulin instruments at various locations in the US LAB and Node 1 has experimentally demonstrated anisotropic effects in ISS 6A and are used herein to evaluate the adequacy of these revised environmental models.

  4. LEGEND, a LEO-to-GEO Environment Debris Model

    Science.gov (United States)

    Liou, Jer Chyi; Hall, Doyle T.

    2013-01-01

    LEGEND (LEO-to-GEO Environment Debris model) is a three-dimensional orbital debris evolutionary model that is capable of simulating the historical and future debris populations in the near-Earth environment. The historical component in LEGEND adopts a deterministic approach to mimic the known historical populations. Launched rocket bodies, spacecraft, and mission-related debris (rings, bolts, etc.) are added to the simulated environment. Known historical breakup events are reproduced, and fragments down to 1 mm in size are created. The LEGEND future projection component adopts a Monte Carlo approach and uses an innovative pair-wise collision probability evaluation algorithm to simulate the future breakups and the growth of the debris populations. This algorithm is based on a new "random sampling in time" approach that preserves characteristics of the traditional approach and captures the rapidly changing nature of the orbital debris environment. LEGEND is a Fortran 90-based numerical simulation program. It operates in a UNIX/Linux environment.

  5. A Dynamic/Anisotropic Low Earth Orbit (LEO) Ionizing Radiation Model

    Science.gov (United States)

    Badavi, Francis F.; West, Katie J.; Nealy, John E.; Wilson, John W.; Abrahms, Briana L.; Luetke, Nathan J.

    2006-01-01

    The International Space Station (ISS) provides the proving ground for future long duration human activities in space. Ionizing radiation measurements in ISS form the ideal tool for the experimental validation of ionizing radiation environmental models, nuclear transport code algorithms, and nuclear reaction cross sections. Indeed, prior measurements on the Space Transportation System (STS; Shuttle) have provided vital information impacting both the environmental models and the nuclear transport code development by requiring dynamic models of the Low Earth Orbit (LEO) environment. Previous studies using Computer Aided Design (CAD) models of the evolving ISS configurations with Thermo Luminescent Detector (TLD) area monitors, demonstrated that computational dosimetry requires environmental models with accurate non-isotropic as well as dynamic behavior, detailed information on rack loading, and an accurate 6 degree of freedom (DOF) description of ISS trajectory and orientation.

  6. An Assessment of the Current LEO Debris Environment and the Need for Active Debris Removal

    Science.gov (United States)

    Liou, Jer-Chyi

    2010-01-01

    The anti-satellite test on the Fengun-1 C weather satellite in early 2007 and the collision between Iridium 33 and Cosmos 2251 in 2009 dramatically altered the landscape of the human-made orbital debris environment in the low Earth orbit (LEO). The two events generated approximately 5500 fragments large enough to be tracked by the U.S. Space Surveillance Network. Those fragments account for more than 60% increase to the debris population in LEO. However, even before the ASAT test, model analyses already indicated that the debris population (for those larger than 10 cm) in LEO had reached a point where the population would continue to increase, due to collisions among existing objects, even without any future launches. The conclusion implies that as satellites continue to be launched and unexpected breakup events continue to occur, commonly-adopted mitigation measures will not be able to stop the collision-driven population growth. To remediate the debris environment in LEO, active debris removal must be considered. This presentation will provide an updated assessment of the debris environment after the Iridium 33/Cosmos 2251 collision, an analysis of several future environment projections based on different scenarios, and a projection of collision activities in LEO in the near future. The need to use active debris removal to stabilize future debris environment will be demonstrated and the effectiveness of various active debris removal strategies will be quantified.

  7. Ionizing radiation in environment

    International Nuclear Information System (INIS)

    Jandl, J.; Petr, I.

    1988-01-01

    The basic terms are explained such as the atom, radioactivity, nuclear reaction, interaction of ionizing radiation with matter, etc. The basic dosimetric variables and units and properties of radionuclides and ionizing radiation are given. Natural and artificial sources of ionizing radiation are discussed with regard to the environment and the propagation and migration of radionuclides is described in the environment to man. The impact is explained of ionizing radiation on the cell and the somatic and genetic effects of radiation on man are outlined. Attention is devoted to protection against ionizing radiation and to radiation limits, also to the detection, dosimetry and monitoring of ionizing radiation in the environment. (M.D.). 92 figs., 40 tabs. 74 refs

  8. Natural radiation environment III

    International Nuclear Information System (INIS)

    Gesell, T.F.; Lowder, W.M.

    1980-01-01

    Separate abstracts were prepared for the 52 research papers presented at this symposium in April 1978. The major topics in this volume deal with penetrating radiation measurements, radiation surveys and population exposure, radioactivity in the indoor environment, and technologically enhanced natural radioactivity

  9. Radiation environment at Kalpakkam

    International Nuclear Information System (INIS)

    Iyengar, M.A.R.

    1989-01-01

    Nuclear facilities located at Kalpakkam in Tamil Nadu State of India include at present nuclear power reactors, a fast breeder reactor, a nuclear research centre and a waste management facility. Active wastes generated at the site are collected, treated and safely disposed. High-level wastes are stored underground in RCC trenches and tile hole and low-level wastes in the from of liquid effluents are discharged into the sea. Off-gases are dispersed through stacks in the atmosphere. Environmental survey laboratory established at the site in 1974 carries out radiation surveillance of the environment, evaluates radiological impacts on environment and public, and assesses radiation exposure of the population. It is observed that even after five years of operation of the nuclear power station, radioactivity and radiation levels in the environment have virtually remained at the pre-operational levels. (M.G.B.). 14 figs., 4 tabs

  10. Natural radiation environment III

    International Nuclear Information System (INIS)

    Gesell, T.F.; Lowder, W.M.

    1980-01-01

    Separate abstracts were prepared for the 57 research papers presented at this symposium in April 1978 at Houston, Texas. This symposium provided a common forum for scientists in several disciplines that deal with natural radiation because there is an increasing interest in the environment as it pertains to human health and the competition for scarce energy and material resources

  11. Radiation Environment of Phobos

    Science.gov (United States)

    Cooper, John F.; Clark, John H.; Sturner, Steven J.; Stubbs, Timothy; Wang, Yongli; Glenar, David A.; Schwadron, Nathan A.; Joyce, Colin J.; Spence, Harlan E.; Farrell, William M.

    2017-10-01

    The innermost Martian moon Phobos is a potential way station for the human exploration of Mars and the solar system beyond the orbit of Mars. It has a similar radiation environment to that at 1 AU for hot plasma and more energetic particles from solar, heliospheric and galactic sources. In the past two decades there have been many spacecraft measurements at 1 AU, and occasionally in the Mars orbital region around the Sun, that can be used to define a reference model for the time-averaged and time-variable radiation environments at Mars and Phobos. Yearly to hourly variance comes from the eleven-year solar activity cycle and its impact on solar energetic, heliospheric, and solar-modulated galactic cosmic ray particles. We report progress on compilation of the reference model from U.S. and international spacecraft data sources of the NASA Space Physics Data Facility and the Virtual Energetic Particle Observatory (VEPO), and from tissue-equivalent dosage rate measurements by the CRaTER instrument on the Lunar Reconnaissance Observer spacecraft now in lunar orbit. Similar dosage rate data are also available from the Mars surface via the NASA Planetary Data System archive from the Radiation Assessment Detector (RAD) instrument aboard the Mars Science Laboratory (MSL) Curiosity rover. The sub-Mars surface hemisphere of Phobos is slightly blocked from energetic particle irradiation by the body of Mars but there is a greater global variance of interplanetary radiation exposure as we have calculated from the known topography of this irregularly shaped moon. Phobos receives a relatively small flux of secondary radiation from galactic cosmic ray interactions with the Mars surface and atmosphere, and at plasma energies from pickup ions escaping out of the Mars atmosphere. The greater secondary radiation source is from cosmic ray interactions with the moon surface, which we have simulated with the GEANT radiation transport code for various cases of the surface regolith

  12. A Parametric Study on Using Active Debris Removal to Stabilize the Future LEO Debris Environment

    Science.gov (United States)

    Liou, J.C.

    2010-01-01

    Recent analyses of the instability of the orbital debris population in the low Earth orbit (LEO) region and the collision between Iridium 33 and Cosmos 2251 have reignited the interest in using active debris removal (ADR) to remediate the environment. There are; however, monumental technical, resources, operational, legal, and political challenges in making economically viable ADR a reality. Before a consensus on the need for ADR can be reached, a careful analysis of the effectiveness of ADR must be conducted. The goal is to demonstrate the feasibility of using ADR to preserve the future environment and to guide its implementation to maximize the benefit-cost ratio. This paper describes a comprehensive sensitivity study on using ADR to stabilize the future LEO debris environment. The NASA long-term, orbital debris evolutionary model, LEGEND, is used to quantify the effects of many key parameters. These parameters include (1) the starting epoch of ADR implementation, (2) various target selection criteria, (3) the benefits of collision avoidance maneuvers, (4) the consequence of targeting specific inclination or altitude regimes, (5) the consequence of targeting specific classes of vehicles, and (6) the timescale of removal. Additional analyses on the importance of postmission disposal and how future launches might affect the requirements to stabilize the environment are also included.

  13. Radiation Environment Inside Spacecraft

    Science.gov (United States)

    O'Neill, Patrick

    2015-01-01

    Dr. Patrick O'Neill, NASA Johnson Space Center, will present a detailed description of the radiation environment inside spacecraft. The free space (outside) solar and galactic cosmic ray and trapped Van Allen belt proton spectra are significantly modified as these ions propagate through various thicknesses of spacecraft structure and shielding material. In addition to energy loss, secondary ions are created as the ions interact with the structure materials. Nuclear interaction codes (FLUKA, GEANT4, HZTRAN, MCNPX, CEM03, and PHITS) transport free space spectra through different thicknesses of various materials. These "inside" energy spectra are then converted to Linear Energy Transfer (LET) spectra and dose rate - that's what's needed by electronics systems designers. Model predictions are compared to radiation measurements made by instruments such as the Intra-Vehicular Charged Particle Directional Spectrometer (IV-CPDS) used inside the Space Station, Orion, and Space Shuttle.

  14. A Parametric Study on Using Active Debris Removal for LEO Environment Remediation

    Science.gov (United States)

    2010-01-01

    Recent analyses on the instability of the orbital debris population in the low Earth orbit (LEO) region and the collision between Iridium 33 and Cosmos 2251 have reignited the interest in using active debris removal (ADR) to remediate the environment. There are; however, monumental technical, resource, operational, legal, and political challenges in making economically viable ADR a reality. Before a consensus on the need for ADR can be reached, a careful analysis of its effectiveness must be conducted. The goal is to demonstrate the need and feasibility of using ADR to better preserve the future environment and to guide its implementation to maximize the benefit-to-cost ratio. This paper describes a new sensitivity study on using ADR to stabilize the future LEO debris environment. The NASA long-term orbital debris evolutionary model, LEGEND, is used to quantify the effects of several key parameters, including target selection criteria/constraints and the starting epoch of ADR implementation. Additional analyses on potential ADR targets among the currently existing satellites and the benefits of collision avoidance maneuvers are also included.

  15. Radiation in living environment

    International Nuclear Information System (INIS)

    Ichikawa, R.

    1991-01-01

    Aside from the atomic bomb attacks in 1945, the experience of radioactive contamination of human environment was the exposure of a tuna fishing boat to the radioactive fallout of a hydrogen bomb test explosion at Bikini atoll in March, 1954. Thereafter, radioactivity was frequently detected in fishes in central Pacific Ocean. Radioactivity was also detected in rain, which resulted in the contamination of agricultural products. Due to the great concern of general public for the radioactivity in food materials, the government initiated the national program of radioactivity surveillance. Since then, the fallout radioactivity due to nuclear test explosions was the main object surveillance in 1950s and 1960s, but the program was gradually expanded to include natural radiation, the artificial radioactivity due to the peaceful uses of nuclear energy and other special programs. The history of the radioactive contamination of environment, natural radiation, medical exposure, the radioactive fallout due to nuclear tests, nuclear power generation and the Chernobyl accident are reported. (K.I.)

  16. Ionizing Radiation Environments and Exposure Risks

    Science.gov (United States)

    Kim, M. H. Y.

    2015-12-01

    Space radiation environments for historically large solar particle events (SPE) and galactic cosmic rays (GCR) are simulated to characterize exposures to radio-sensitive organs for missions to low-Earth orbit (LEO), moon, near-Earth asteroid, and Mars. Primary and secondary particles for SPE and GCR are transported through the respective atmospheres of Earth or Mars, space vehicle, and astronaut's body tissues using NASA's HZETRN/QMSFRG computer code. Space radiation protection methods, which are derived largely from ground-based methods recommended by the National Council on Radiation Protection and Measurements (NCRP) or International Commission on Radiological Protections (ICRP), are built on the principles of risk justification, limitation, and ALARA (as low as reasonably achievable). However, because of the large uncertainties in high charge and energy (HZE) particle radiobiology and the small population of space crews, NASA develops distinct methods to implement a space radiation protection program. For the fatal cancer risks, which have been considered the dominant risk for GCR, the NASA Space Cancer Risk (NSCR) model has been developed from recommendations by NCRP; and undergone external review by the National Research Council (NRC), NCRP, and through peer-review publications. The NSCR model uses GCR environmental models, particle transport codes describing the GCR modification by atomic and nuclear interactions in atmospheric shielding coupled with spacecraft and tissue shielding, and NASA-defined quality factors for solid cancer and leukemia risk estimates for HZE particles. By implementing the NSCR model, the exposure risks from various heliospheric conditions are assessed for the radiation environments for various-class mission types to understand architectures and strategies of human exploration missions and ultimately to contribute to the optimization of radiation safety and well-being of space crewmembers participating in long-term space missions.

  17. Space Flight Ionizing Radiation Environments

    Science.gov (United States)

    Koontz, Steve

    2017-01-01

    The space-flight ionizing radiation (IR) environment is dominated by very high-kinetic energy-charged particles with relatively smaller contributions from X-rays and gamma rays. The Earth's surface IR environment is not dominated by the natural radioisotope decay processes. Dr. Steven Koontz's lecture will provide a solid foundation in the basic engineering physics of space radiation environments, beginning with the space radiation environment on the International Space Station and moving outward through the Van Allen belts to cislunar space. The benefits and limitations of radiation shielding materials will also be summarized.

  18. Material interactions with the Low Earth Orbital (LEO) environment: Accurate reaction rate measurements

    Science.gov (United States)

    Visentine, James T.; Leger, Lubert J.

    1987-01-01

    To resolve uncertainties in estimated LEO atomic oxygen fluence and provide reaction product composition data for comparison to data obtained in ground-based simulation laboratories, a flight experiment has been proposed for the space shuttle which utilizes an ion-neutral mass spectrometer to obtain in-situ ambient density measurements and identify reaction products from modeled polymers exposed to the atomic oxygen environment. An overview of this experiment is presented and the methodology of calibrating the flight mass spectrometer in a neutral beam facility prior to its use on the space shuttle is established. The experiment, designated EOIM-3 (Evaluation of Oxygen Interactions with Materials, third series), will provide a reliable materials interaction data base for future spacecraft design and will furnish insight into the basic chemical mechanisms leading to atomic oxygen interactions with surfaces.

  19. Analysis of MIR-18 results for physical and biological dosimetry: radiation shielding effectiveness in LEO

    Science.gov (United States)

    Cucinotta, F. A.; Wilson, J. W.; Williams, J. R.; Dicello, J. F.

    2000-01-01

    We compare models of radiation transport and biological response to physical and biological dosimetry results from astronauts on the Mir space station. Transport models are shown to be in good agreement with physical measurements and indicate that the ratio of equivalent dose from the Galactic Cosmic Rays (GCR) to protons is about 3/2:1 and that this ratio will increase for exposures to internal organs. Two biological response models are used to compare to the Mir biodosimetry for chromosome aberration in lymphocyte cells; a track-structure model and the linear-quadratic model with linear energy transfer (LET) dependent weighting coefficients. These models are fit to in vitro data for aberration formation in human lymphocytes by photons and charged particles. Both models are found to be in reasonable agreement with data for aberrations in lymphocytes of Mir crew members: however there are differences between the use of LET dependent weighting factors and track structure models for assigning radiation quality factors. The major difference in the models is the increased effectiveness predicted by the track model for low charge and energy ions with LET near 10 keV/micrometers. The results of our calculations indicate that aluminum shielding, although providing important mitigation of the effects of trapped radiation, provides no protective effect from the galactic cosmic rays (GCR) in low-earth orbit (LEO) using either equivalent dose or the number of chromosome aberrations as a measure until about 100 g/cm 2 of material is used.

  20. Natural radiation in the environment

    International Nuclear Information System (INIS)

    Moeller, D.W.

    1990-01-01

    The speaker discusses natural radiation in the environment. He outlines the external sources of exposure (cosmic and terrestrial), as well as the internal sources (ingestion and inhalation). He states that a clear understanding of these sources and their impacts is necessary in order to properly evaluate both the environment and human radiation exposure

  1. Operational specification and forecasting advances for Dst, LEO thermospheric densities, and aviation radiation dose and dose rate

    Science.gov (United States)

    Tobiska, W. Kent

    Space weather’s effects upon the near-Earth environment are due to dynamic changes in the energy transfer processes from the Sun’s photons, particles, and fields. Of the space environment domains that are affected by space weather, the magnetosphere, thermosphere, and even troposphere are key regions that are affected. Space Environment Technologies (SET) has developed and is producing innovative space weather applications. Key operational systems for providing timely information about the effects of space weather on these domains are SET’s Magnetosphere Alert and Prediction System (MAPS), LEO Alert and Prediction System (LAPS), and Automated Radiation Measurements for Aviation Safety (ARMAS) system. MAPS provides a forecast Dst index out to 6 days through the data-driven, redundant data stream Anemomilos algorithm. Anemomilos uses observational proxies for the magnitude, location, and velocity of solar ejecta events. This forecast index is used by satellite operations to characterize upcoming geomagnetic storms, for example. In addition, an ENLIL/Rice Dst prediction out to several days has also been developed and will be described. LAPS is the SET fully redundant operational system providing recent history, current epoch, and forecast solar and geomagnetic indices for use in operational versions of the JB2008 thermospheric density model. The thermospheric densities produced by that system, driven by the LAPS data, are forecast to 72-hours to provide the global mass densities for satellite operators. ARMAS is a project that has successfully demonstrated the operation of a micro dosimeter on aircraft to capture the real-time radiation environment due to Galactic Cosmic Rays and Solar Energetic Particles. The dose and dose-rates are captured on aircraft, downlinked in real-time via the Iridium satellites, processed on the ground, incorporated into the most recent NAIRAS global radiation climatology data runs, and made available to end users via the web and

  2. Radiated EMC& EMI Management During Design Qualification and Test Phases on LEO Satellites Constellation

    Science.gov (United States)

    Blondeaux, H.; Terral, M.; Gutierrez-Galvan, R.; Baud, C.

    2016-05-01

    The aim of the proposed paper is to present the global radiated EMC/EMI approach applied by Thales Alenia Space in the frame of a telecommunication Low Earth Orbit (LEO) satellites constellation program. The paper will present this approach in term of analyses, of specific characterisation and of sub-system and satellite tests since first design reviews up-to satellite qualification tests on Prototype Flight Model (PFM) and to production tests on reduced FMs. The global aim is : 1 - to reduce risk and cost (units EMC delta qualification, EMC tests at satellite level for the 81 Space Vehicles (SV) through appropriated EMC analyses (in term of methodologies and contours) provided in the frame of design reviews.2 - to early anticipate potential critical case to reduce the impact in term of engineering/qualification/test extra cost and of schedule.3 - to secure/assure the payload and SV design/layout.4 - to define and optimize the EMC/EMI test campaigns to be performed on Prototype Flight Model (PFM) for complete qualification and on some FMs for industrial qualification/validation.The last part of the paper is dedicated to system Bite Error Rate (BER) functional test performed on PFM SV to demonstrate the final compatibility between the three on-board payloads and to the Internal EMC tests performed on PFM and some FMs to demonstrate the SV panel RF shielding efficiency before and after environmental tests and the Thales Alenia Space (TAS) and Orbital AKT (OATK) workmanships reproducibility.

  3. Radiation, people and the environment

    International Nuclear Information System (INIS)

    Ford, J.

    2004-02-01

    Radiation is a fact of life. We live in a world in which radiation is naturally present everywhere. Light and heat from nuclear reactions in the Sun are essential to our existence. Radioactive materials occur naturally throughout the environment, and our bodies contain radioactive materials such as carbon-14, potassium-40 and polonium-210 quite naturally. All life on Earth has evolved in the presence of this radiation. Since the discovery of X rays and radioactivity more than 100 years ago, we have found ways of producing radiation and radioactive materials artificially. The first use of X rays was in medical diagnosis, within six months of their discovery in 1895. So a benefit from the use of radiation was established very early on, but equally some of the potential dangers of radiation became apparent in the doctors and surgeons who unwittingly overexposed themselves to X rays in the early 1900s. Since then, many different applications of radiation and radioactive materials have been developed. We can classify radiation according to the effects it produces on matter, into ionizing and non-ionizing radiation. Ionizing radiation includes cosmic rays, X rays and the radiation from radioactive materials. Non-ionizing radiation includes ultraviolet light, radiant heat, radio waves and microwaves. This book deals with ionizing radiation, a term, which for simplicity, is often shortened to just radiation. It has been prepared by the International Atomic Energy Agency (IAEA) in co-operation with the National Radiological Protection Board (United Kingdom) as a broad overview of the subject of ionizing radiation, its effects and uses, as well as the measures in place to use it safely. As the United Nations agency for nuclear science and its peaceful applications, the IAEA offers a broad spectrum of expertise and programmes to foster the safe use of radiation internationally

  4. Radiation chemistry and the environment

    International Nuclear Information System (INIS)

    Getoff, F.

    1998-01-01

    The rather strong and many-sided pollution of the environment (atmosphere, water resources, soil) as a consequence of human activities is summarized. The solution of the arised problems by application of radiation chemistry methods and the utilization of modern environmentally ''clean'' and economical technologies, founded on electron beam processing, are mentioned. Some basic environmental problems and their solution are briefly discussed: i) Removal of CO 2 from flue gases and its radiation induced utilization. ii) Principals for degradation of aqueous pollutants by electron beam processing in the presence of ozone (synergistic effect). The radiation chemistry as a modern and manifold discipline with very broad applications can also essentially contribute in the conservation of the environment

  5. Radiation chemistry and the environment

    International Nuclear Information System (INIS)

    Getoff, Nikola

    1999-01-01

    The rather strong and many-sided pollution of the environment (atmosphere, water resources, soil) as a consequence of human activity is summarized. The solution of the arised problems by application of radiation chemistry methods and the utilization of modern environmentally 'clean' and economical technologies, founded on electron beam processing, are mentioned. Some basic environmental problems and their solution are briefly discussed. (i) Removal of CO 2 from flue gases and its radiation induced utilization. (ii) Principals for degradation of aqueous pollutants by electron beam processing in the presence of ozone (synergistic effect). The radiation chemistry as a modern and manifold discipline with very broad applications can also essentially contribute in the conservation of the environment

  6. Cleaner Environment Through Radiation Technologies

    International Nuclear Information System (INIS)

    Venkatesh, M.

    2015-01-01

    Radioisotopes and radiation based technologies are widely used in a huge variety of industries to improve efficiency, enhance quality, optimize processes, achieve high performance materials, increase safety, for trouble shooting and so on. Many such applications are not known even to professionals with scientific background. This presentation is aimed at outlining some of these technologies which influence our daily life and contribute to better quality of life. In particular, the role of radiation based techniques in providing better environment through mitigation pollutants in industrial effluents as well as being a clean technology will be highlighted. (author)

  7. Updating the NASA LEO Orbital Debris Environment Model with Recent Radar and Optical Observations and in Situ Measurements

    Science.gov (United States)

    Liou, J.-C.; Anz-Meador, P.; Matney, M. J.; Kessler, D. J.; Theall, J.; Johnson, N. L.

    2000-01-01

    The Low Earth Orbit (LEO, between 200 and 2000 km altitudes) debris environment has been constantly measured by NASA Johnson Space Center's Liquid Mirror Telescope (LMT) since 1996 (Africano et al. 1999, NASA JSC-28826) and by Haystack and Haystack Auxiliary radars at MIT Lincoln Laboratory since 1990 (Settecerri et al. 1999, NASA JSC-28744). Debris particles as small as 3 mm can be detected by the radars and as small as 3 cm can be measured by LMT. Objects about 10 cm in diameter and greater are tracked and catalogued by the US Space Surveillance Network. Much smaller (down to several micrometers) natural and debris particle populations can be estimated based on in situ measurements, such as Long Duration Exposure Facility, and based on analyses of returned surfaces, such as Hubble Space Telescope solar arrays, European Retrievable Carrier, and Space Shuttles. To increase our understanding of the current LEO debris environment, the Orbital Debris Program Office at NASA JSC has initiated an effort to improve and update the ORDEM96 model (Kessler et al. 1996, NASA TM-104825) utilizing the recently available data. This paper gives an overview of the new NASA orbital debris engineering model, ORDEM2000.

  8. SPACE RADIATION ENVIRONMENT MONITORED BY KITSAT-1 AND KITSAT-2

    Directory of Open Access Journals (Sweden)

    Y. H. Shin

    1996-06-01

    Full Text Available The results of space radiation experiments carried out on board the first two Korean technology demonstration microsatellites are presented in this paper. The first satellite, KITSAT-1, launched in August 1992, carries a radiation monitoring payload called cosmic ray experiment(CRE for characterizing the low-earth orbit(LEO radiation environment. The CRE consists of two sub-systems: the cosmic particle experiment (CPE and the total dose experiment(TDE. In addition, single event upset(SEUrates of the program memory and the RAM disk are also monitored. The second satellite, KITSAT-2, launched in September 1993, carries a newly developed 32-bit on-board computer(OBC, KASCOM(KAIST satellite computer in addition to OBC186. SEUs ocurred in the KASCOM, as well as in the program memory and RAM disk memory, have been monitored since the beginning of the satellite operation. These two satellites, which are very similar in structures but different in orbits, provide a unique opportunity to study the effects of the radiation environment characterized by the orbit.

  9. Nanosatellites in LEO and beyond: Advanced Radiation protection techniques for COTS-based spacecraft

    Science.gov (United States)

    Selčan, David; Kirbiš, Gregor; Kramberger, Iztok

    2017-02-01

    This paper presents an approach for implementing radiation protection FDIR (Fault Detection, Isolation and Recovery) techniques designed especially for nanosatellites, capable of ensuring reliable operation in harsh orbits using COTS (Commercial off the Shelf) components. The radiation environment, as encountered by nanosatellites utilizing Flash-based FPGAs in orbits higher than Low Earth Orbit, is analyzed, primarily focusing on SEE (Single Event Effects). In order to assure reliable operation, the FDIR policy is split into two levels: the Low Level FDIR which ensures that no permanent damage occurs to the satellite's electronics, which then allows the use of a High Level FDIR tasked with maintaining high availability. A hierarchical approach, consisting of three types of current limiters in combination with watchdog timers and fault tolerant logic implemented inside a flash-based FPGA is proposed for the Low Level FDIR. The impacts of various radiation-induced faults are analyzed with respect to how the FDIR techniques mitigate them. The proposed current limiters and watchdog timers have been implemented and evaluated for suitability of use with the hierarchical FDIR policy. In order to decrease the impacts on the size and weight footprints, the current limiters were implemented as stacked 3D modules.

  10. Radiation effects in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Begay, F.; Rosen, L.; Petersen, D.F.; Mason, C.; Travis, B. [Los Alamos National Lab., NM (United States); Yazzie, A. [Navajo Nation, Window Rock, AZ (United States). Dept. of History; Isaac, M.C.P.; Seaborg, G.T. [Lawrence Berkeley National Lab., CA (United States); Leavitt, C.P. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Physics and Astronomy

    1999-04-01

    Although the Navajo possess substantial resource wealth-coal, gas, uranium, water-this potential wealth has been translated into limited permanent economic or political power. In fact, wealth or potential for wealth has often made the Navajo the victims of more powerful interests greedy for the assets under limited Navajo control. The primary focus for this education workshop on the radiation effects in the environment is to provide a forum where scientists from the nuclear science and technology community can share their knowledge toward the advancement and diffusion of nuclear science and technology issues for the Navajo public. The scientists will make an attempt to consider the following basic questions; what is science; what is mathematics; what is nuclear radiation? Seven papers are included in this report: Navajo view of radiation; Nuclear energy, national security and international stability; ABC`s of nuclear science; Nuclear medicine: 100 years in the making; Radon in the environment; Bicarbonate leaching of uranium; and Computational methods for subsurface flow and transport. The proceedings of this workshop will be used as a valuable reference materials in future workshops and K-14 classrooms in Navajo communities that need to improve basic understanding of nuclear science and technology issues. Results of the Begay-Stevens research has revealed the existence of strange and mysterious concepts in the Navajo Language of nature. With these research results Begay and Stevens prepared a lecture entitled The Physics of Laser Fusion in the Navajo language. This lecture has been delivered in numerous Navajo schools, and in universities and colleges in the US, Canada, and Alaska.

  11. Proceeding of Radiation Safety and Environment

    International Nuclear Information System (INIS)

    1996-01-01

    Scientific Presentation of Radiation Safety and Environment was held on 20-21 august 1996 at Center of Research Atomic Energy Pasar Jum'at, Jakarta, Indonesia. Have presented 50 papers about Radiation Safety, dosimetry and standardization, environment protection and radiation effect

  12. The Martian Energetic Radiation Environment Models

    Science.gov (United States)

    Gonçalves, Patrícia; Keating, Ana; Truscott, Pete; Lei, Fan; Desorgher, Laurent; Heynderickx, Daniel; Crosby, Norma Bock; Nieminen, Petteri; Santin, Giovanni

    The Martian Energetic Radiation Environment Models The high energy ionising radiation environment in the solar system consists of three main sources: the planetary radiation belts, galactic cosmic rays and solar energetic particles. Future Mars missions potentially carry significant risk from long-term exposure to ionising radiation. The Martian Energetic Radiation Environment Models, MEREM, were developed in order to simulate the Martian radiation environment. The models, eMEREM and dMEREM, respec-tively engineering and detailed Martian Energetic Radiation Environment Models, are based on the Geant4 and FLUKA radiation transport programs, combined with Mars Climate Database model for the atmosphere. MOLA (Mars Orbiter Laser Altimeter) data and gamma-ray spec-trometer data have been used to define surface topology and surface composition (including presence of water), respectively. Although the models are capable of operating on standalone mode, a SPENVIS (space envi-ronment information system) compatible, web-based user interface was developed to provide an integrated environment to predict the Martian radiation and greatly simplify the operation of the software by non-experts and by future mission developers. Results of the Mars Energetic Radiation Environment Models concerning the estimate of effec-tive doses and ambient dose equivalents for potential Martian landing sites having regard to the combined incidence, under solar minimum and solar maximum conditions, of flare related particle radiation and background galactic cosmic ray radiation are presented.

  13. Using of ionizing radiation in environment protection

    International Nuclear Information System (INIS)

    Kuruc, J.

    1997-01-01

    In this paper, there is given the review of application of the radiation chemistry techniques in the environment protection . Using of sources of ionization radiation in underground water, drinking water and waste waters as well as in exhaust gases radiation processing and treatment are reviewed [sk

  14. Radiation pollution of the environment

    International Nuclear Information System (INIS)

    Benalashhar, Hanan Ali

    2006-01-01

    This paper interested in the topic of environmental pollution by radioactive materials due to several human activities. The meaning of human activities are nuclear tests and extraction of raw uranium, waste and reactor accidents, nuclear fuel and radon gas, and the peaceful uses of radiation. This paper points out the effects of environmental pollution by radiation and the means of reduction, and also illustrate the radiation pollution in the Arab region. (author)

  15. Natural radiation environment III. [Lead Abstract

    Energy Technology Data Exchange (ETDEWEB)

    Gesell, T.F.; Lowder, W.M. (eds.)

    1980-01-01

    Separate abstracts were prepared for the 52 research papers presented at this symposium in April 1978. The major topics in this volume deal with penetrating radiation measurements, radiation surveys and population exposure, radioactivity in the indoor environment, and technologically enhanced natural radioactivity. (KRM)

  16. Construction of a Matched Global Cloud and Radiance Product from LEO/GEO and EPIC Observations to Estimate Daytime Earth Radiation Budget from DSCOVR

    Science.gov (United States)

    Duda, David P.; Khlopenkov, Konstantin V.; Thiemann, Mandana; Palikonda, Rabindra; Sun-Mack, Sunny; Minnis, Patrick; Su, Wenying

    2016-01-01

    With the launch of the Deep Space Climate Observatory (DSCOVR), new estimates of the daytime Earth radiation budget can be computed from a combination of measurements from the two Earth-observing sensors onboard the spacecraft, the Earth Polychromatic Imaging Camera (EPIC) and the National Institute of Standards and Technology Advanced Radiometer (NISTAR). Although these instruments can provide accurate top-of-atmosphere (TOA) radiance measurements, they lack sufficient resolution to provide details on small-scale surface and cloud properties. Previous studies have shown that these properties have a strong influence on the anisotropy of the radiation at the TOA, and ignoring such effects can result in large TOA-flux errors. To overcome these effects, high-resolution scene identification is needed for accurate Earth radiation budget estimation. Selected radiance and cloud property data measured and derived from several low earth orbit (LEO, including NASA Terra and Aqua MODIS, NOAA AVHRR) and geosynchronous (GEO, including GOES (east and west), METEOSAT, INSAT-3D, MTSAT-2, and HIMAWARI-8) satellite imagers were collected to create hourly 5-km resolution global composites of data necessary to compute angular distribution models (ADM) for reflected shortwave (SW) and longwave (LW) radiation. The satellite data provide an independent source of radiance measurements and scene identification information necessary to construct ADMs that are used to determine the daytime Earth radiation budget. To optimize spatial matching between EPIC measurements and the high-resolution composite cloud properties, LEO/GEO retrievals within the EPIC fields of view (FOV) are convolved to the EPIC point spread function (PSF) in a similar manner to the Clouds and the Earth's Radiant Energy System (CERES) Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product. Examples of the merged LEO/GEO/EPIC product will be presented, describing the chosen radiance and cloud properties and

  17. Development of environment radiation database management system

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Jong Gyu; Chung, Chang Hwa; Ryu, Chan Ho; Lee, Jin Yeong; Kim, Dong Hui; Lee, Hun Sun [Daeduk College, Taejon (Korea, Republic of)

    1999-03-15

    In this development, we constructed a database for efficient data processing and operating of radiation-environment related data. Se developed the source documents retrieval system and the current status printing system that supports a radiation environment dta collection, pre-processing and analysis. And, we designed and implemented the user interfaces and DB access routines based on WWW service policies on KINS Intranet. It is expected that the developed system, which organizes the information related to environmental radiation data systematically can be utilize for the accurate interpretation, analysis and evaluation.

  18. Development of environment radiation database management system

    International Nuclear Information System (INIS)

    Kang, Jong Gyu; Chung, Chang Hwa; Ryu, Chan Ho; Lee, Jin Yeong; Kim, Dong Hui; Lee, Hun Sun

    1999-03-01

    In this development, we constructed a database for efficient data processing and operating of radiation-environment related data. Se developed the source documents retrieval system and the current status printing system that supports a radiation environment dta collection, pre-processing and analysis. And, we designed and implemented the user interfaces and DB access routines based on WWW service policies on KINS Intranet. It is expected that the developed system, which organizes the information related to environmental radiation data systematically can be utilize for the accurate interpretation, analysis and evaluation

  19. The Ionizing Radiation Environment on the Moon

    Science.gov (United States)

    Adams, J. H., Jr.; Bhattacharya, M.; Lin, Zi-Wei; Pendleton, G.

    2006-01-01

    The ionizing radiation environment on the moon that contributes to the radiation hazard for astronauts consists of galactic cosmic rays, solar energetic particles and albedo particles from the lunar surface. We will present calculations of the absorbed dose and the dose equivalent to various organs in this environment during quiet times and during large solar particle events. We will evaluate the contribution of solar particles other than protons and the contributions of the various forms of albedo. We will use the results to determine which particle fluxes must be known in order to estimate the radiation hazard.

  20. AD620SQ/883B Total Ionizing Dose Radiation Lot Acceptance Report for RESTORE-LEO

    Science.gov (United States)

    Burton, Noah; Campola, Michael

    2017-01-01

    A Radiation Lot Acceptance Test was performed on the AD620SQ/883B, Lot 1708D, in accordance with MIL-STD-883, Method 1019, Condition D. Using a Co-60 source 4 biased parts and 4 unbiased parts were irradiated at 10 mrad/s (0.036 krad/hr) in intervals of approximately 1 krad from 3-10 krads, and ones of 5 krads from 10-25 krads, where it was annealed while unbiased at 25 degrees Celsius, for 2 days, and then, subsequently, annealed while biased at 25 degrees celsius, for another 7 days.

  1. Radiation environment of fusion experimental reactor

    International Nuclear Information System (INIS)

    Mori, Seiji; Seki, Yasushi

    1988-01-01

    Next step device (experimental reactor), which is planned to succeed the large plasma experimental devices such as JT-60, JET and TFTR, generates radiation (neutron + gamma ray) during its operation. Radiation (neutronic) properties of the material are basis for the study on neutron utilization (energy recovery and tritium breeding), material selection (irradiation damage and lifetime evaluation) and radiation safety (personnel exposure and radiation waste). It is necessary, therefore, to predict radiation behaviour in the reactor correctly for the engineering design of the reactor. This report describes the outline of the radiation environment of the reactor based on the information obtained by the neutronic and shielding design calculation of the fusion experimental reactor (FER). (author)

  2. Role of Personality in Behavioral Responses to New Environments in Captive Asiatic Lions (Panthera leo persica)

    Science.gov (United States)

    Quintavalle Pastorino, Giovanni; Viau, Anna; Curone, Giulio; Pearce-Kelly, Paul; Faustini, Massimo; Vigo, Daniele; Preziosi, Richard

    2017-01-01

    Studying personality in captive animals may enable the development of individual-based management decisions, which may improve animal welfare. Asiatic lions at London Zoo represent an opportunity to research an understudied species' response to new environments since they have experienced social and physical changes, such as new enclosures and increased social interaction with humans. This project aimed to investigate the role of personality in behavioral responses to these changes. Lion personality questionnaires completed by keepers and direct focal animal observations were used to create personality profiles. Time budgets and enclosure use were determined and compared between control nights and event nights and between the lions' previous enclosure and their new one. The results showed a lack of difference in time budget and enclosure use between control and social event nights, and the spread of participation index values revealed that the lions use their enclosures unevenly. Personality profiles identified various traits that could assist with individual-based management decisions. As the first study to assess Asiatic lions personality, this research contributes to the creation of consistent and valid methodology for evaluating captive animal personality that may improve husbandry and welfare protocols for individual lions, leading to the improved health and success of the species. PMID:28638674

  3. Role of Personality in Behavioral Responses to New Environments in Captive Asiatic Lions (Panthera leo persica

    Directory of Open Access Journals (Sweden)

    Giovanni Quintavalle Pastorino

    2017-01-01

    Full Text Available Studying personality in captive animals may enable the development of individual-based management decisions, which may improve animal welfare. Asiatic lions at London Zoo represent an opportunity to research an understudied species’ response to new environments since they have experienced social and physical changes, such as new enclosures and increased social interaction with humans. This project aimed to investigate the role of personality in behavioral responses to these changes. Lion personality questionnaires completed by keepers and direct focal animal observations were used to create personality profiles. Time budgets and enclosure use were determined and compared between control nights and event nights and between the lions’ previous enclosure and their new one. The results showed a lack of difference in time budget and enclosure use between control and social event nights, and the spread of participation index values revealed that the lions use their enclosures unevenly. Personality profiles identified various traits that could assist with individual-based management decisions. As the first study to assess Asiatic lions personality, this research contributes to the creation of consistent and valid methodology for evaluating captive animal personality that may improve husbandry and welfare protocols for individual lions, leading to the improved health and success of the species.

  4. The dynamic radiation environment assimilation model (DREAM)

    Energy Technology Data Exchange (ETDEWEB)

    Reeves, Geoffrey D [Los Alamos National Laboratory; Koller, Josef [Los Alamos National Laboratory; Tokar, Robert L [Los Alamos National Laboratory; Chen, Yue [Los Alamos National Laboratory; Henderson, Michael G [Los Alamos National Laboratory; Friedel, Reiner H [Los Alamos National Laboratory

    2010-01-01

    The Dynamic Radiation Environment Assimilation Model (DREAM) is a 3-year effort sponsored by the US Department of Energy to provide global, retrospective, or real-time specification of the natural and potential nuclear radiation environments. The DREAM model uses Kalman filtering techniques that combine the strengths of new physical models of the radiation belts with electron observations from long-term satellite systems such as GPS and geosynchronous systems. DREAM includes a physics model for the production and long-term evolution of artificial radiation belts from high altitude nuclear explosions. DREAM has been validated against satellites in arbitrary orbits and consistently produces more accurate results than existing models. Tools for user-specific applications and graphical displays are in beta testing and a real-time version of DREAM has been in continuous operation since November 2009.

  5. [UV-radiation--sources, wavelength, environment].

    Science.gov (United States)

    Hölzle, Erhard; Hönigsmann, Herbert

    2005-09-01

    The UV-radiation in our environment is part of the electromagnetic radiation, which emanates from the sun. It is designated as optical radiation and reaches from 290-4,000 nm on the earth's surface. According to international definitions UV irradiation is divided into short-wave UVC (200-280 nm), medium-wave UVB (280-320 nm), and long-wave UVA (320-400 nm). Solar radiation which reaches the surface of the globe at a defined geographical site and a defined time point is called global radiation. It is modified quantitatively and qualitatively while penetrating the atmosphere. Besides atmospheric conditions, like ozone layer and air pollution, geographic latitude, elevation, time of the season, time of the day, cloudiness and the influence of indirect radiation resulting from stray effects in the atmosphere and reflection from the underground play a role in modifying global radiation, which finally represents the biologically effective radiation. The radiation's distribution on the body surface varies according to sun angle and body posture. The cumulative UV exposure is mainly influenced by outdoor profession and recreational activities. The use of sun beds and phototherapeutic measures additionally may contribute to the cumulative UV dose.

  6. Ionizing radiations and dosimetry in space environment

    International Nuclear Information System (INIS)

    Doke, Tadayoshi

    1990-01-01

    Recently, plans have been developed for the construction of bases on the moon and launch of manned spacecraft to Mars. In the present report, the level of radiations in space, possible exposure of astronauts to radiations, appropriate levels of permissible exposure to such radiations, and available techniques to measure the dose equivalent are discussed in relation to long stays of astronauts in space outside the magnetosphere. Specifically, the report first outlines major features of radiations in the space environment focusing on electron and proton beams caught by the terrestrial magnitism, radiations released by the sun and galactic cosmic rays, and then presents estimations of possible exposure dose in space focusing on the contributions of electron and proton beams caught by the terrestrial magnetism, radiations released by the sun and galactic cosmic rays. The report also addresses guidelines for protection from radiations in space, techniques for measuring the intensity of radiations in space. It is pointed out that more studies should be made to permit accurate measurement of radiation doses in a mixed field containing high-energy heavy particles. (N.K.)

  7. The natural radiation environment: future perspective

    International Nuclear Information System (INIS)

    Steinhaeusler, F.

    1992-01-01

    The need to control the exposure of man to the natural radiation environment (NRE) is increasingly recognised. The main NRE sources and exposure situations warranting intensified efforts in the future are: exposure to radiation in space (astronaut: ≤ 1 mSv.d -1 ), technologically enhanced natural radiation (TENR; global impact: 400,000 man.Sv.y -1 ) and populations living in high background radiation areas (resident: ≤ 360 mGy.y -1 ). Data on NRE-TENR-induced biological effects are scarce and inconclusive, such as increased frequency of chromosome aberrations and mental retardation from environmental gamma radiation, but there are contradictory results for thorium and radon exposure induced lung cancer risk. Four coordinated actions are proposed, i.e. international standardisation of methods, coordination of multidisciplinary health effect studies, development of principles for NRE/TENR control, and establishment of an international clearing house for all NRE-related topics. (Author)

  8. The Radiation Environment of Exoplanet Atmospheres

    Directory of Open Access Journals (Sweden)

    Jeffrey L. Linsky

    2014-10-01

    Full Text Available Exoplanets are born and evolve in the radiation and particle environment created by their host star. The host star’s optical and infrared radiation heats the exoplanet’s lower atmosphere and surface, while the ultraviolet, extreme ultraviolet and X-radiation control the photochemistry and mass loss from the exoplanet’s upper atmosphere. Stellar radiation, especially at the shorter wavelengths, changes dramatically as a host star evolves leading to changes in the planet’s atmosphere and habitability. This paper reviews the present state of our knowledge concerning the time-dependent radiation emitted by stars with convective zones, that is stars with spectral types F, G, K, and M, which comprise nearly all of the host stars of detected exoplanets.

  9. Nuclear medicine and the environment: radiation interactions

    International Nuclear Information System (INIS)

    Schmelter, R.F.

    1986-01-01

    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. 72 references

  10. Radiation and environment - impact studies awareness

    International Nuclear Information System (INIS)

    Boniface Ekechukwu; Mohd. Zohadie Bardaie

    2005-01-01

    Radiation, which is simply defined as energy, that travels in the form of waves or particles has both positive and negative effects on humans. This has necessitated a careful study on how to create awareness on the 'two-edge sword'. Since radiation cannot be removed from our environment we, however, reduce our risks by controlling our exposure to it through various ways. Understanding radiation and radioactivity will help us make informed decisions about our exposure. Many difference types of radiation have range of energy that form electromagnetic spectrum. Their sources include nuclear power plants, nuclear weapons, and medicine. Others include, microwaves, radar, electrical power lines, cellular phones, and sunlight' and so on. However, the radiation used in nuclear power, nuclear weapons, and medicine has enough energy to break chemical bonds, and is referred to as 'ionizing radiation', which is dangerous to life. Because of this negative effect of radiation there is common fear and myths related to radiation, radioactivity, uranium mining and milling, and the nuclear industry. This radiation education and energy-environmental education attempt to dispel the common fears and myths relating to them in so far as there is perfect protection from harmful exposure and abuse. The design of an integrated unit of study radiation and environmental energy uses arts of language, life skills, skill designs, social studies and mathematical skills in creating understanding and abilities necessary to do scientific inquiry by the students without abuse or danger. The education unit is designed to assess materials for, factual information and appropriate language and identification of potential bias in environmental education materials and evaluate materials in perspective of cultural and ethnic upbringing. (author)

  11. Radiation protection of the environment - new trends

    International Nuclear Information System (INIS)

    Povinec, P. P.

    2006-01-01

    Recent trends in the radiation protection of the environment focusing on basic changes of the protection philosophy from the egocentric to ecocentric approach are presented and discussed. The globalization of the economy is accompanied by global contamination of the environment that requires changes in the attitude of the protection of the total environment, i.e. protection of humans, fauna and flora, all ecosystems and the Earth in general, as well as the cosmic space. This complex approach is illustrated on the radiation protection of the environment that has always been in the forefront in developing protection philosophy, methodology and standards, which later has also been applied to the protection of the environment caused by non-radioactive contaminants, such as heavy metals and organic compounds. High radiation doses delivered to biota are illustrated on shellfish and fish collected in the Mururoa and Fangataufa lagoons (affected by series of nuclear weapons tests), and on fish in Novaya Zemlya bays (affected by dumping of nuclear reactors and radioactive wastes). On the methodological site an example is discussed focusing on the in situ sea-bed radionuclide mapping and seawater monitoring using submersible gamma-ray spectrometers operating with NaI(Tl) and HPGe detectors which has proved to be important pre-requisite for estimation of the spatial distribution of radionuclides in the water column and on the sea floor, as well as for optimisation of sediment sampling for studying the radionuclide distribution with depth

  12. Optical Fibers in Nuclear Reactor Radiation Environments.

    Science.gov (United States)

    Holcomb, David Eugene

    1992-01-01

    A performance evaluation of fiber optics under radiation conditions similar to those encountered in nuclear power plants is reported. The evaluation was accomplished by the creation of an analytical model for atomic scale radiation damage in silica glass and by the execution of an extensive fiber performance measurement program. The analytic model calculates displacement and electronic damage rates for silica glass subjected to a specified nuclear reactor radiation environment. It accomplishes this by first generating the primary charged particle spectrum produced in silica irradiated in a nuclear reactor. The resultant spectra are then applied to the integral equations describing radiation damage in polyatomic solids. The experimental measurements were selected to span the range of fiber types, radiation environments, temperatures, and light powers expected to be used in nuclear power plants. The basic experimental protocol was to expose the optical fibers to either a nuclear reactor or a ^{60}Co radiation environment while simultaneously monitoring fiber light transmission. Experimental temperatures were either ~23 ^circC or ~100 ^circC and light powers were either -30 dBm or -60 dBm. Measurements were made at each of the three standard communications wavelengths (850 nm, 1300 nm, and 1550 nm). Several conclusions are made based on these performance measurements. First, even near the core of a nuclear reactor the vast majority of the dose to silica glass is due to gamma rays. Even with the much lower doses (factor of roughly 40) neutrons cause much more displacement damage than gamma rays (35 times the oxygen displacement rate and 500 times the silicon displacement rate). Even with neutrons having many times the displacement rate as compared with gamma rays, little if any difference is observed in the transmission losses for gamma only as compared to mixed neutron/gamma transmission losses. Therefore, atomic displacement is not a significant damage mechanism for

  13. Radiation diagnostics in extremely harsh environments

    International Nuclear Information System (INIS)

    Dona, H.; Lee, P.H.Y.; Williams, A.H.; McGurn, J.L.; Veeser, L.R.

    1986-01-01

    Some recent Trailmaster experiments have required to use of rather delicate radiation diagnostics in hostile environments. We have developed instrumentation for use high-explosive magnetic flux compression generators and near the noisy environment of high energy capacitor banks. These include some rather unique ''fly-away'' designs for x-ray imaging and spectroscopy, and other optical techniques for plasma temperature and field measurements. We will show some representative data and will also discuss an on-going program for the determination of magnetic field via atomic spectral line splitting and/or broadening

  14. Updating the Jovian Proton Radiation Environment - 2015

    Science.gov (United States)

    Garrett, Henry; Martinez-Sierra, Luz Maria; Evans, Robin

    2015-01-01

    Since publication in 1983 by N. Divine and H. Garrett, the Jet Propulsion Laboratory's plasma and radiation models have been the design standard for NASA's missions to Jupiter. These models consist of representations of the cold plasma and electrons, the warm and auroral electrons and protons, and the radiation environment (electron, proton, and heavy ions). To date, however, the high-energy proton model has been limited to an L-shell of 12. With the requirement to compute the effects of the high energy protons and other heavy ions on the proposed Europa mission, the extension of the high energy proton model from approximately 12 L-shell to approximately 50 L-shell has become necessary. In particular, a model of the proton environment over that range is required to estimate radiation effects on the solar arrays for the mission. This study describes both the steps taken to extend the original Divine proton model out to an approximately 50 L-shell and the resulting model developed to accomplish that goal. In addition to hydrogen, the oxygen, sulfur, and helium heavy ion environments have also been added between approximately 6 L-shell and approximately 50 L-shell. Finally, selected examples of the model's predictions are presented to illustrate the uses of the tool.

  15. The Global Environment Radiation Monitoring Network (GERMON)

    International Nuclear Information System (INIS)

    Zakheim, B.J.; Goellner, D.A.

    1994-01-01

    Following the Chernobyl accident in 1986, a group of experts from the World Health Organization (WHO) and the United Nations Environment Program (UNEP) met in France to discuss and develop the basic principles of a global environmental radiation monitoring network (GERMON). The basic functions of this network were to provide regular reports on environmental radiation levels and to be in a position to provide reliable and accurate radiation measurements on a quick and accurate radiation measurements on a quick turnaround basis in the event of a major radiation release. By 1992, although 58 countries had indicated an interest in becoming a part of the GERMON system, only 16 were providing data on a regular basis. This paper traces the history of GERMON from its inception in 1987 through its activities during 1993-4. It details the objectives of the network, describes functions, lists its participants, and presents obstacles in the current network. The paper examines the data requirements for radiological emergency preparedness and offers suggestions for the current system. The paper also describes the growing need for such a network. To add a domestic perspective, the authors present a summary of the environmental monitoring information system that was used by the NRC in 1986 in its analyses of the Chernobyl incident. Then we will use this 1986 experience to propose a method for the use of GERMON should a similar occasion arise in the future

  16. Use of COTS microelectronics in radiation environments

    International Nuclear Information System (INIS)

    Winokur, P.S.; Lum, G.K.; Shaneyfelt, M.R.; Sexton, F.W.; Hash, G.L.; Scott, L.

    1999-01-01

    This paper addresses key issues for the cost-effective use of COTS (Commercially available Off The Shelf) microelectronics in radiation environments that enable circuit or system designers to manage risks and ensure mission success. They review several factors and tradeoffs affecting the successful application of COTS parts including (1) hardness assurance and qualification issues, (2) system hardening techniques, and (3) life-cycle costs. The paper also describes several experimental studies that address trends in total-dose, transient, and single-event radiation hardness as COTS technology scales to smaller feature sizes. As an example, the level at which dose-rate upset occurs in Samsung SRAMs increases from 1.4 x 10 8 rad(Si)/s for a 256K SRAM to 7.7 x 10 9 rad(Si)/s for a 4M SRAM, indicating unintentional hardening improvements in the design of process of a commercial technology. Additional experiments were performed to quantify variations in radiation hardness for COTS parts. In one study, only small (10--15%) variations were found in the dose-rate upset and latchup thresholds for Samsung 4M SRAMs from three different date codes. In another study, irradiations of 4M SRAMs from Samsung, Hitachi, and Toshiba indicate large differences in total-dose radiation hardness. The paper attempts to carefully define terms and clear up misunderstandings about the definitions of COTS and radiation-hardened (RH) technology

  17. Dynamic Radiation Environment Assimilation Model: DREAM

    Science.gov (United States)

    Reeves, G. D.; Chen, Y.; Cunningham, G. S.; Friedel, R. W. H.; Henderson, M. G.; Jordanova, V. K.; Koller, J.; Morley, S. K.; Thomsen, M. F.; Zaharia, S.

    2012-03-01

    The Dynamic Radiation Environment Assimilation Model (DREAM) was developed to provide accurate, global specification of the Earth's radiation belts and to better understand the physical processes that control radiation belt structure and dynamics. DREAM is designed using a modular software approach in order to provide a computational framework that makes it easy to change components such as the global magnetic field model, radiation belt dynamics model, boundary conditions, etc. This paper provides a broad overview of the DREAM model and a summary of some of the principal results to date. We describe the structure of the DREAM model, describe the five major components, and illustrate the various options that are available for each component. We discuss how the data assimilation is performed and the data preprocessing and postprocessing that are required for producing the final DREAM outputs. We describe how we apply global magnetic field models for conversion between flux and phase space density and, in particular, the benefits of using a self-consistent, coupled ring current-magnetic field model. We discuss some of the results from DREAM including testing of boundary condition assumptions and effects of adding a source term to radial diffusion models. We also describe some of the testing and validation of DREAM and prospects for future development.

  18. Materials Degradation in the Jovian Radiation Environment

    Science.gov (United States)

    Miloshevsky, Gennady; Caffrey, Jarvis A.; Jones, Jonathan E.; Zoladz, Thomas F.

    2017-01-01

    The radiation environment of Jupiter represents a significant hazard for Europa Lander deorbit stage components, and presents a significant potential mission risk. The radiolytic degradation of ammonium perchlorate (AP) oxidizer in solid propellants may affect its properties and performance. The Monte Carlo code MONSOL was used for modeling of laboratory experiments on the electron irradiation of propellant samples. An approach for flattening dose profiles along the depth of irradiated samples is proposed. Depth-dose distributions produced by Jovian electrons in multi-layer slabs of materials are calculated. It is found that the absorbed dose in a particular slab is significantly affected by backscattered electrons and photons from neighboring slabs. The dose and radiolytic decomposition of AP crystals are investigated and radiation-induced chemical yields and weight percent of radical products are reported.

  19. Radiation Effects in the Space Telecommunications Environment

    International Nuclear Information System (INIS)

    Fleetwood, Daniel M.; Winokur, Peter S.

    1999-01-01

    Trapped protons and electrons in the Earth's radiation belts and cosmic rays present significant challenges for electronics that must operate reliably in the natural space environment. Single event effects (SEE) can lead to sudden device or system failure, and total dose effects can reduce the lifetime of a telecommmiications system with significant space assets. One of the greatest sources of uncertainty in developing radiation requirements for a space system is accounting for the small but finite probability that the system will be exposed to a massive solar particle event. Once specifications are decided, standard laboratory tests are available to predict the total dose response of MOS and bipolar components in space, but SEE testing of components can be more challenging. Prospects are discussed for device modeling and for the use of standard commercial electronics in space

  20. Radiation Effects in the Space Telecommunications Environment

    Energy Technology Data Exchange (ETDEWEB)

    Fleetwood, Daniel M.; Winokur, Peter S.

    1999-05-17

    Trapped protons and electrons in the Earth's radiation belts and cosmic rays present significant challenges for electronics that must operate reliably in the natural space environment. Single event effects (SEE) can lead to sudden device or system failure, and total dose effects can reduce the lifetime of a telecommmiications system with significant space assets. One of the greatest sources of uncertainty in developing radiation requirements for a space system is accounting for the small but finite probability that the system will be exposed to a massive solar particle event. Once specifications are decided, standard laboratory tests are available to predict the total dose response of MOS and bipolar components in space, but SEE testing of components can be more challenging. Prospects are discussed for device modeling and for the use of standard commercial electronics in space.

  1. Utilization of radiation for preservation of environment

    International Nuclear Information System (INIS)

    Washino, Masamitsu

    1976-01-01

    The utilization of radiation for sludge treatment, waste water treatment and exhaust gas treatment is reviewed. The conversion of sludge into fertilizer is difficult in Japan, because heavy metals that came from industrial waste water are contained in sewage water. If the techniques for treating industrial waste water and the measures for regionally separating waste water are established, the less fertile earth due to excess use of agricultural chemicals and synthetic fertilizers will recover its fertility. Problems of activated sludge treatment are as follows: 1) requirement for wide plant area, 2) difficulty of meeting the wide variation of loads, and 3) existence of agricultural chemicals and detergents which are not decomposable by microorganisms. The irradiation method may be one of the techniques for reusing waste water by high quality treatment. The mechanism of radiation effects is physicochemically explained. The research on the electron beam treatment exhaust gas in heavy oil combustion made by Japan Atomic Energy Research Institute and Ebara Manufacturing Company is illustrated. The experiment revealed that 1) sulfurous acid and nitrogen oxides in exhaust gas can be removed simultaneously; 2) a large quantity of gas can be treated with a large output accelerator in a short time, and 3) reaction products can be separated with electric dust collectors. In future, the research on the utilization of radiation for environment preservation will result in the closed systems because of the prevention of public pollution and the effective utilization of natural resources. (Iwakiri, K.)

  2. Modeling of the Lunar Radiation Environment

    International Nuclear Information System (INIS)

    De Angelis, G.; Badavi, F.F.; Clem, J.M.; Blattnig, S.R.; Clowdsley, M.S.; Nealy, J.E.; Tripathi, R.K.; Wilson, J.W.

    2007-01-01

    In view of manned missions targeted to the Moon, for which radiation exposure is one of the greatest challenges to be tackled, it is of fundamental importance to have available a tool, which allows the determination of the particle flux and spectra at any time and at any point of the lunar surface. With this goal in mind, a new model of the Moon's radiation environment due to Galactic Cosmic Rays (GCR) and Solar Particle Events (SPE) has been developed. Primary particles reach the lunar surface, and are transported all throughout the subsurface layers, with backscattering patterns taken into account. The surface itself has been modeled as regolith and bedrock, with composition taken from the results of the instruments flown on the Apollo missions. Subsurface environments like lava tubes have been considered in the analysis. Particle transport has been performed with both deterministic and Monte Carlo codes with an adaptation for planetary surface geometry. Results are given in terms of fluxes, doses and LET, for most kinds of particles for various kinds of soil and rock chemical compositions

  3. Development of radiation processes for better environment

    International Nuclear Information System (INIS)

    Majali, A.B.; Sabharwal, S.; Deshpande, R.S.; Sarma, K.S.S.; Bhardwaj, Y.K.; Dhanawade, B.R.

    1998-01-01

    The increasing population and industrialization, worldover, is placing escalating demands for the development of newer technologies that are environment friendly and minimize the pollution associated with the development. Radiation technology can be of benefit in reducing the pollution levels associated with many processes. The sulphur vulcanization method for natural rubber latex vulcanization results in the formation of considerable amounts of nitrosoamines, both in the product as well as in the factory environment. Radiation vulcanization of natural rubber latex has emerged as a commercially viable alternative to produce sulphur and nitrosoamine free rubber. A Co-60 γ-radiation based pilot plant has been functioning since April 1993 to produce vulcanized natural rubber latex (RVNRL) using acrylate monomers as sensitizer. The role of sensitizer, viz. n-butyl acrylate in the vulcanization process has been elucidated using the pulse radiolysis technique. Emission of toxic sulphur containing gases form an inevitable part of viscose-rayon process and this industry is in search of ways to reduce the associated pollution levels. The irradiation of cellulose results in cellulose activation and reduction in the degree of polymerization (DP). These effects can reduce the solvents required to dissolve the paper pulp. There is a keen interest in utilizing radiation technology in viscose rayon production. We have utilized the electron beam (EB) accelerator for reducing the degree of polymerization (DP) of paper pulp. Laboratory scale tests have been carried out to standardize the conditions for production of pulp having the desired DP by EB irradiation. The use of irradiated paper pulp can result in ∼40% reduction in the consumption of CS 2 in the process that can be beneficial in reducing the pollution associated with the process. PTFE waste can be recycled into a low molecular weight microfine powder by irradiation. An EB based process has been standardized to produce

  4. Organism/Organic Exposure to Orbital Stresses (OOREOS) Satellite: Radiation Exposure in LEO and Supporting Laboratory Studies

    Science.gov (United States)

    Mattioda, Andrew Lige; Cook, Amanda Marie; Quinn, Richard C.; Elsaesser, Andreas; Ehrenfreund, Pascale; Ricca,Alessandra; Jones, Nykola C.; Hoffman, Soren; Ricco,Antonio

    2014-01-01

    We will present the results from the exposure of the metalloporphyrin iron tetraphenylporphyrin chloride (FeTPPCI), anthraufin (C(sub 14)H(sub 8)(O sub 4) (Anth) and Isoviolanthrene (C(sub 34H sub 18) (IVA) to the outher space environment, measured in situ aboard the Organism/Organic Exposure to Orbital Stresses nanosatellite. The compounds were exposed for a period of 17 months (3700 hours of direct solar exposure) including broad-spectrum solar radiation (approx. 122 nm to the near infrared). The organic films are enclosed in hermetically sealed sample cells that contain one of four astrobiologically relevant microenvironments. Transmission spectra (200-1000 nm) were recorded for each film, at first daily and subsequently every 15 days, along with a solar spectrum and the dark response of the detector array. In addition to analysis via UV-Vis spectroscopy, the laboratory controls were also monitored via infrared and far-UV spectroscopy. The results presented will include the finding that the FeTPPCI and IVA organic films in contact with a humid headspace gas (0.8-2.3%) exhibit faster degradation times, upon irradiation, in comparison with identical films under dry headspaces gases, whereas the Anth thin film exhibited a higher degree of photostability. In the companion laboratory experiments, simulated solar exposure of FeTPI films in contact with either Ar or CO(sub -2):O(sub -2):Ar (10:0.01:1000) headspace gas results in growth of a band in the films infrared spectra at 1961 cm(sup 1). Our assignment of this new spectral feature and the corresponding rational will be presented. The relevance of O/OREOS findings to planetary science, biomarker research, and the photostability of organic materials in astrobiologically relevant environments will also be discussed.

  5. Geant4 applications in the heliospheric radiation environment

    OpenAIRE

    Brogueira, Pedro; Gonçalves, Patrícia; Keating, Ana; Maia, Dalmiro; Pimenta, Mário; Tomé, Bernardo

    2007-01-01

    The high energy ionizing radiation environment in the solar system consists of three main sources: the radiation belts, galactic cosmic rays and solar energetic particles. Geant4 is a Monte Carlo radiation transport simulation toolkit, with applications in areas as high energy physics, nuclear physics, astrophysics or medical physics research. In this poster, Geant4 applications to model and study the effects of the heliospheric radiation environment are presented. Specific applications are b...

  6. The ionizing radiation environment in space and its effects

    International Nuclear Information System (INIS)

    Adams, Jim; Falconer, David; Fry, Dan

    2012-01-01

    The ionizing radiation environment in space poses a hazard for spacecraft and space crews. The hazardous components of this environment are reviewed and those which contribute to radiation hazards and effects identified. Avoiding the adverse effects of space radiation requires design, planning, monitoring and management. Radiation effects on spacecraft are avoided largely though spacecraft design. Managing radiation exposures of space crews involves not only protective spacecraft design and careful mission planning. Exposures must be managed in real time. The now-casting and forecasting needed to effectively manage crew exposures is presented. The techniques used and the space environment modeling needed to implement these techniques are discussed.

  7. High Radiation Environment Nuclear Fragment Separator Magnet

    Energy Technology Data Exchange (ETDEWEB)

    Kahn, Stephen [Muons, Inc., Batavia, IL (United States); Gupta, Ramesh [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-01-31

    Superconducting coils wound with HTS conductor can be used in magnets located in a high radiation environment. NbTi and Nb3Sn superconductors must operate at 4.5 K or below where removal of heat is less efficient. The HTS conductor can carry significant current at higher temperatures where the Carnot efficiency is significantly more favorable and where the coolant heat capacity is much larger. Using the HTS conductor the magnet can be operated at 40 K. This project examines the use of HTS conductor for the Michigan State University Facility For Rare Isotope Beams (FRIB) fragment separator dipole magnet which bends the beam by 30° and is located in a high radiation region that will not be easily accessible. Two of these magnets are needed to select the chosen isotope. There are a number of technical challenges to be addressed in the design of this magnet. The separator dipole is 2 m long and subtends a large angle. The magnet should keep a constant transverse field profile along its beam reference path. Winding coils with a curved inner segment is difficult as the conductor will tend to unwind during the process. In the Phase I project two approaches to winding the conductor were examined. The first was to wind the coils with curved sections on the inner and outer segments with the inner segment wound with negative curvature. The alternate approach was to use a straight segment on the inner segment to avoid negative curvature. In Phase I coils with a limited number of turns were successfully wound and tested at 77 K for both coil configurations. The Phase II program concentrated on the design, coil winding procedures, structural analysis, prototyping and testing of an HTS curved dipole coil at 40 K with a heat load representative of the radiation environment. One of the key criteria of the design of this magnet is to avoid the use of organic materials that would degrade rapidly in radiation. The Lorentz forces expected from the coils interacting with the

  8. Reliability of computer memories in radiation environment

    Directory of Open Access Journals (Sweden)

    Fetahović Irfan S.

    2016-01-01

    Full Text Available The aim of this paper is examining a radiation hardness of the magnetic (Toshiba MK4007 GAL and semiconductor (AT 27C010 EPROM and AT 28C010 EEPROM computer memories in the field of radiation. Magnetic memories have been examined in the field of neutron radiation, and semiconductor memories in the field of gamma radiation. The obtained results have shown a high radiation hardness of magnetic memories. On the other side, it has been shown that semiconductor memories are significantly more sensitive and a radiation can lead to an important damage of their functionality. [Projekat Ministarstva nauke Republike Srbije, br. 171007

  9. Coastal sea radiation environment and biodiversity protection

    International Nuclear Information System (INIS)

    Tang Senming; Shang Zhaorong

    2009-01-01

    This paper characterizes the types, trend and the potential of radiation contamination in the sea against the development of nuclear power stations. Combined with the present status of radioactive contamination and marine biodiversity in China seas, it is pointed out that non-human radiation protection should be considered on the bases of marine biodiversity protection. Besides, the reference species for marine radiation protection and some viewpoints on the work of marine radiation protection in China are pro- posed. (authors)

  10. Radiation monitoring in the NPP environment, control of radioactivity in NPP-environment system

    International Nuclear Information System (INIS)

    Egorov, Yu.A.

    1987-01-01

    Problems of radiation monitoring and control of the NPP-environment system (NPPES) are considered. Radiation control system at the NPP and in the environment provides for the control of the NPP, considered as the source of radioactive releases in the environment and for the environmental radiation climate control. It is shown, that the radiation control of the NPP-environment system must be based on the ecological normalization principles of the NPP environmental impacts. Ecological normalization should be individual for the NPP region of each ecosystem. The necessity to organize and conduct radiation ecological monitoring in the NPP regions is pointed out. Radiation ecological monitoring will provide for both environmental current radiation control and information for mathematical models, used in the NPPES radiation control

  11. Development of advanced silicon radiation detectors for harsh radiation environment

    CERN Document Server

    Groenlund, Tanja

    2012-01-01

    This thesis describes the development of advanced silicon radiation detectors and their characterization by simulations, used in the work for searching elementary particles in the European Organization for Nuclear Research, CERN. Silicon particle detectors will face extremely harsh radiation in the proposed upgrade of the Large Hadron Collider, the future high-energy physics experiment Super-LHC. The increase in the maximal fluence and the beam luminosity up to 1016 neq / cm2 and 1035 cm-2s-1 will require detectors with a dramatic improvement in radiation hardness, when such a fluence will be far beyond the operational limits of the present silicon detectors. The main goals of detector development concentrate on minimizing the radiation degradation. This study contributes mainly to the device engineering technology for developing more radiation hard particle detectors with better characteristics. Also the defect engineering technology is discussed. In the nearest region of the beam in Super-LHC, the only dete...

  12. Ionizing Radiation Environment on the International Space Station: Performance vs. Expectations for Avionics and Material

    Science.gov (United States)

    Koontz, Steven L.; Boeder, Paul A.; Pankop, Courtney; Reddell, Brandon

    2005-01-01

    The role of structural shielding mass in the design, verification, and in-flight performance of International Space Station (ISS), in both the natural and induced orbital ionizing radiation (IR) environments, is reported. Detailed consideration of the effects of both the natural and induced ionizing radiation environment during ISS design, development, and flight operations has produced a safe, efficient manned space platform that is largely immune to deleterious effects of the LEO ionizing radiation environment. The assumption of a small shielding mass for purposes of design and verification has been shown to be a valid worst-case approximation approach to design for reliability, though predicted dependences of single event effect (SEE) effects on latitude, longitude, SEP events, and spacecraft structural shielding mass are not observed. The Figure of Merit (FOM) method over predicts the rate for median shielding masses of about 10g/cm(exp 2) by only a factor of 3, while the Scott Effective Flux Approach (SEFA) method overestimated by about one order of magnitude as expected. The Integral Rectangular Parallelepiped (IRPP), SEFA, and FOM methods for estimating on-orbit (Single Event Upsets) SEU rates all utilize some version of the CREME-96 treatment of energetic particle interaction with structural shielding, which has been shown to underestimate the production of secondary particles in heavily shielded manned spacecraft. The need for more work directed to development of a practical understanding of secondary particle production in massive structural shielding for SEE design and verification is indicated. In contrast, total dose estimates using CAD based shielding mass distributions functions and the Shieldose Code provided a reasonable accurate estimate of accumulated dose in Grays internal to the ISS pressurized elements, albeit as a result of using worst-on-worst case assumptions (500 km altitude x 2) that compensate for ignoring both GCR and secondary particle

  13. Evaluation of the Radiation Environment of the LHCb Experiment

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00341385; Corti, Gloria

    The unprecedented radiation levels of the Large Hadron Collider (LHC) during high-energy proton-proton collisions will have an impact on the operation of its experiments’ detectors and electronics. LHCb, one of the 4 major LHC experiments, has started operation in 2009 and from 2011 onward it has been collecting data at and above its design luminosity. Detectors and associated detector electronics are prone to damage if the radiation levels exceed the expected values. It is essential to monitor the radiation environment of the experimental area and compare it with predictions obtained from simulation studies in order to assess the situation and take corrective action in case of need. Understanding the existing radiation environment will also provide important input to the planning of maintenance and for operation at upgrade luminosity. A set of radiation detectors has been installed in the LHCb experimental area to measure different aspects of its radiation environment. Passive dosimeters including Thermo-L...

  14. Radiation and global environment. Consideration for the influence on ecosystems

    International Nuclear Information System (INIS)

    Muramatsu, Yasuyuki; Doi, Masahiro; Yoshida, Satoshi

    2003-09-01

    This book is based on presentations at the National Institute of Radiological Sciences (NIRS) symposium of the same title held by the NIRS Research Center for Radiation Safety in December, 2002, is edited with somehow enlightening intention as well, and is composed from 6 parts of; 1. Reasons for concern for influence on ecosystems, 2. Behavior of substances in ecosystems, 3. Changes of global environments and life, 4. Various environmental stresses and living/eco-systems, 5. New development of evaluation studies on radiation effects, and 6. For the radiation protection of environments. The 1st part involves 3 chapters concerning studies on effects on ecosystems and radiation protection of environments; 2nd part, 4 chapters concerning behavior of radioactive and/or stable cesium and iodine in forest and environmental microorganisms, and behavior and effects of acidic substances; 3rd part, 2 chapters concerning terrestrial history and evolution/adaptation of livings; 4th part, 5 chapters concerning radiation stress, active oxygen, radiodurance/radio-resistant microorganisms, ultraviolet, and environmental hormones; 5th part, 6 chapters concerning effects on cells of environmental toxic substance and radiation, environmental stress evaluation by DNA micro-array, effects on taxis, use of microcosm, simulation of computational model ecosystem, and aquatic ecosystems; 6th part, 5 chapters concerning environmental radioecology, safety measures in high-level radioactive waste disposal under the ground, radiation protection of environments from radiation biology aspect, effects of chemicals, and aspect and strategy for radiation effects on environments. (N.I.)

  15. Electric motors for use in radiation environments

    International Nuclear Information System (INIS)

    Aslam, T.U.D.; Mahmood, S.B.

    1981-01-01

    Requirements of electric motors for a nuclear plant and the effect of nuclear radiations on different parts of the motors are discussed. Feasibility of using locally-fabricated motors is also considered. (author)

  16. Overview of Radiation Environments and Human Exposures

    Science.gov (United States)

    Wilson, John W.

    2004-01-01

    Human exposures to ionizing radiation have been vastly altered by developing technology in the last century. This has been most obvious in the development of radiation generating devices and the utilization of nuclear energy. But even air travel has had its impact on human exposure. Human exposure increases with advancing aircraft technology as a result of the higher operating altitudes reducing the protective cover provided by the Earth s atmosphere from extraterrestrial radiations. This increase in operating altitudes is taken to a limit by human operations in space. Less obvious is the changing character of the radiations at higher altitudes. The associated health risks are less understood with increasing altitude due to the increasing complexity and new field components found in high altitude and space operations.

  17. Behaviour of organic materials in radiation environment

    International Nuclear Information System (INIS)

    Tavlet, M.; Ilie, S.

    1999-01-01

    An extensive radiation damage test program has been carried out in CERN for decades and many results have yet been published. Over the years, EPR/EPDM-based rubbers and polyolefin-based compounds used for cable insulation have been tested. Polyolefin-based compounds usually present an important dose-rate effect. This is related to the presence of oxygen, it may be combined with a temperature effect. On the other hand, it appears from many results that the degradation of cable insulations does not depend on the radiation type. Tests of insulating and structural materials after irradiation at cryogenic temperature have shown that there is no significant influence of the irradiation temperature on the radiation degradation of thermo-sets and composites, while the degradation of plastic films is even less severe as they are protected against oxidation. Some experiments about the synergy between irradiation and mechanical stress have shown that rubbers and composites under stress are more sensitive to radiation and degrade faster. Very strong synergetic effects between radiation and other parameters are observed in organic optical materials such as scintillators and optical fibres. For fluorocarbon cooling fluids, a special care must be paid to alkanes and hydro-fluoro-alkanes, which are usually present as impurities, and of which the C-H bonds content opens the way to the reactive hydrofluoric acid evolution during the radiolytic process

  18. Techniques for predicting environment electromagnetic radiation at satellite ground station

    International Nuclear Information System (INIS)

    Xu Peiji

    1987-01-01

    The measurement theories, techniques, and calculation methods on public exposure level of electromagnetic radiation at satellite ground station are described for the purpose of enviroment protection and research of EM compatibility. According to the results of the measurement and calculation, it is possible to predict the effects of electromagnetic radiation to environment at satellite ground station

  19. Emergency Medical Rescue in a Radiation Environment

    International Nuclear Information System (INIS)

    Briesmeister, L.; Ellington, Y.; Hollis, R.; Kunzman, J.; McNaughton, M.; Ramsey, G.; Somers, B.; Turner, A.; Finn, J.

    1999-01-01

    Previous experience with emergency medical rescues in the presence of radiation or contamination indicates that the training provided to emergency responders is not always appropriate. A new course developed at Los Alamos includes specific procedures for emergency response in a variety of radiological conditions

  20. The case against protecting the environment from ionising radiation

    International Nuclear Information System (INIS)

    Smith, J.T.

    2004-01-01

    The objective of this paper is to present the (rarely heard) argument in favour of retention of the present system of radiation protection of the environment. There has been a recent trend in the radioecological and radiation protection community towards greater regulation of the effects of ionising radiations on biota. In particular, the often quoted International Commission on Radiation Protection (ICRP) hypothesis that: If humans are protected from the effects of ionising radiation, then flora and fauna are also adequately protected has been criticised as being too anthropocentric and not adequate for protection of the environment. In this paper I will challenge this view, arguing firstly that this statement is almost always quoted out of its proper context, and secondly that the ICRP hypothesis does adequately protect the environment from the effects of ionising radiations. In view of the relatively insignificant effect of regulated releases of ionising radiation on the environment, the economic cost of further regulation will not result in a significant environmental benefit. Whilst empirical research to test the ICRP hypothesis should continue, until there is clear evidence against it, this simple and cost-effective approach should be retained. This would benefit the environment by directing scarce resources to more urgent environmental problems. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    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. Radiation Environments and their Impact at the CERN's Injector Chain

    CERN Document Server

    De Carvalho Saraiva, Joao Pedro; CERN. Geneva. ATS Department

    2015-01-01

    Mixed particle and energy radiation fields present at the Large Hadron Collider (LHC) and its Injector Chain are responsible for failures on electronic devices located in the vicinity of the accelerator beam lines. These radiation effects on electronics and, more generally, the overall radiation damage issues have a direct impact on component and system lifetimes, as well as on maintenance requirements and radiation exposure to personnel who have to intervene and fix the faults. This note describes the different radiation environments present along the CERN’s Injector Chain and the expected evolution over the next years with the ongoing LHC Injectors Upgrade (LIU) project. The available dosimetry and beam monitoring systems used to assess radiation levels are presented, outlining their respective pros and cons. The interplay between Monte Carlo simulations and the available radiation monitoring in the Injectors is also presented.

  3. Integration of optical fibers in radiative environments: Advantages and limitations

    International Nuclear Information System (INIS)

    Girard, S.; Ouerdane, Y.; Boukenter, A.; Marcandella, C.; Bisutti, J.; Baggio, J.; Meunier, J. P.

    2011-01-01

    We review the advantages and limitations for the integration of optical fibers in radiative environments. Optical fibers present numerous advantages for applications in harsh environments such as their electromagnetic immunity. This explains the increasing interest of the radiation effects community to evaluate their vulnerability for future facilities. However, it is also well-known that optical fibers suffer from a degradation of their macroscopic properties under irradiation. We illustrate the major mechanisms and parameters that govern the degradation mechanism, mainly the radiation-induced attenuation phenomena. We focus on the fiber transient radiation responses when exposed to the pulsed and mixed environment associated with the Megajoule class lasers devoted to the fusion by inertial confinement study. (authors)

  4. Leo II PC

    Data.gov (United States)

    Kansas Data Access and Support Center — LEO II is a second-generation software system developed for use on the PC, which is designed to convert location references accurately between legal descriptions and...

  5. Designing equipment for use in gamma radiation environments

    International Nuclear Information System (INIS)

    Vandergriff, K.U.

    1990-05-01

    High levels of gamma radiation are known to cause degradation in a variety of materials and components. When designing systems to operate in a high radiation environment, special precautions and procedures should be followed. This report (1) outlines steps that should be followed in designing equipment and (2) explains the general effects of radiation on various engineering materials and components. Much information exists in the literature on radiation effects upon materials. However, very little information is available to give the designer a step-by-step process for designing systems that will be subject to high levels of gamma radiation, such as those found in a nuclear fuel reprocessing facility. In this report, many radiation effect references are relied upon to aid in the design of components and systems. 11 refs., 4 tabs

  6. Designing Equipment for Use in Gamma Radiation Environments

    Energy Technology Data Exchange (ETDEWEB)

    Vandergriff, K.U.

    1990-01-01

    High levels of gamma radiation are known to cause degradation in a variety of materials and components. When designing systems to operate in a high radiation environment, special precautions and procedures should be followed. This report (1) outlines steps that should be followed in designing equipment and (2) explains the general effects of radiation on various engineering materials and components. Much information exists in the literature on radiation effects upon materials. However, very little information is available to give the designer a step-by-step process for designing systems that will be subject to high levels of gamma radiation, such as those found in a nuclear fuel reprocessing facility. In this report, many radiation effect references are relied upon to aid in the design of components and systems.

  7. Research on environment monitoring of radiation emergency

    CERN Document Server

    Ito, Y; Otani, N

    2003-01-01

    In a case of a nuclear accident at nuclear facilities, strong radiation such as g-rays and neutrons might radiate at a burst in the initial stage. For the establishment of dose estimation system for such accidents, the experiments were done using the He sup + sup 2 beam accelerated by Tandem in the W-MAST. The following results were obtained. 1) Neutron measurements using a rem counter yielded that dose equivalent was about 9.4 mSv/h at a position 100 cm from the Be target when the beam current of 15 MeV He sup 2 sup + was 0.8 mu A. Neutron measurement by means of Au and In foil activation method and by use of TLD element revealed that dose equivalents were to be 16-27 mu Sv/h for thermal neutron, and 30-41 mu Sv/h for sub-fast neutron (20 keV). Therefore, it was concluded that neutron field was mainly composed by fast neutron. 2) Linearity of the rem-counter out put vs neutron flux was valid under the condition that the count rate of the rem-counter was less than 10 kcps. 3) Computer simulation using NRESP c...

  8. Research on environment monitoring of radiation emergency

    CERN Document Server

    Ito, Y

    2002-01-01

    In a case of a nuclear accident at nuclear facilities, radiation such as gamma-rays and neutrons might radiate at a burst in the initial stage. For the establishment of dose estimation system for such accidents, the experiments were carried out using the Tandem/Synchrotron accelerator. The following results were obtained: (1) Measurements of the gamma-ray emission using the NaI detector together with pile up rejection system revealed that the good signals without the pile up phenomena could be obtained in case of count rate less than 7 kc/s. On assumption that energy distribution function of the gamma-rays was proportional to be E exp(- E/T sub e sub f sub f), the effective temperature T sub e sub f sub f was estimated to be 0.8 - 0.9 MeV by use of non-linear least squares. (2) Doses of gamma-rays were measured using the TLD elements shielded by Pb sheets with various widths. The effective temperature T sub e sub f sub f estimated under the same experimental conditions described in (1) was 0.6-3 MeV. In an ac...

  9. Effect of radiation environment on radiation use efficiency and growth of sunflower

    International Nuclear Information System (INIS)

    Bange, M.P.; Hammer, G.L.; Rickert, K.G.

    1997-01-01

    The level of incident radiation and the proportion of radiation that is diffuse affects radiation use efficiency (RUE) in crops. However, the degree of this effect, and its importance to growth and yield of sunflower (Helianthus annuus L.) have not been established. A field experiment was conducted to investigate the effects of radiation environment on RUE, growth, and yield of sunflower. A fully irrigated crop was sown on an alluvial-prairie soil (Fluventic Haplustoll) and was exposed to three distinct radiation environments. In two treatments, the level of incident radiation was reduced by 14 and 20% by suspending two different types of polyethylene plastic films well above the crop. In addition to the reductions in incident radiation, the proportion of radiation that was diffuse was increased by about 14% in these treatments. Lower incident radiation and increased proportion of diffuse radiation had no effect on total biomass, phenology, leaf area, and the canopy light extinction coefficient (k = 0.89). However, yield was reduced in shaded treatments due to smaller grain size and lower harvest index. Although crop RUE measured over the entire crop cycle (1.25 g/MJ) did not differ significantly among treatments, there was a trend where RUE compensated for less intercepted incident radiation. Theoretical derivations of the response of RUE to different levels of incident radiation supported this finding. Shaded sunflower crops have the ability to produce biomass similar to unshaded crops by increasing RUE, but have lower harvest indices

  10. The development of advanced robotics technology in high radiation environment

    International Nuclear Information System (INIS)

    Lee, Yong Bum; Cho, Jaiwan; Lee, Nam Ho; Choi, Young Soo; Park, Soon Yong; Lee, Jong Min; Park, Jin Suk; Kim, Seung Ho; Kim, Byung Soo; Moon, Byung Soo.

    1997-07-01

    In the tele-operation technology using tele-presence in high radiation environment, stereo vision target tracking by centroid method, vergence control of stereo camera by moving vector method, stereo observing system by correlation method, horizontal moving axis stereo camera, and 3 dimensional information acquisition by stereo image is developed. Also, gesture image acquisition by computer vision and construction of virtual environment for remote work in nuclear power plant. In the development of intelligent control and monitoring technology for tele-robot in hazardous environment, the characteristics and principle of robot operation. And, robot end-effector tracking algorithm by centroid method and neural network method are developed for the observation and survey in hazardous environment. 3-dimensional information acquisition algorithm by structured light is developed. In the development of radiation hardened sensor technology, radiation-hardened camera module is designed and tested. And radiation characteristics of electric components is robot system is evaluated. Also 2-dimensional radiation monitoring system is developed. These advanced critical robot technology and telepresence techniques developed in this project can be applied to nozzle-dam installation /removal robot system, can be used to realize unmanned remotelization of nozzle-dam installation / removal task in steam generator of nuclear power plant, which can be contributed for people involved in extremely hazardous high radioactivity area to eliminate their exposure to radiation, enhance their task safety, and raise their working efficiency. (author). 75 refs., 21 tabs., 15 figs

  11. Environment radiation protection - Synthesis and perspectives

    International Nuclear Information System (INIS)

    2006-07-01

    This document presents the principal progresses in the area of risk evaluation to environment in relation with radionuclides during the last five years. It is based on a comparison between the methods that exist for chemical products and this one in progress for radioactive products. The enlightened point concerns the methodologies developed at European scale. The basic concepts of the environmental risk assessment are presented and also its principal components. The knowledge relative to the criteria of environmental protection is presented. The differences between the chemical products and the radioactive products are taken into account. Finally, this document shows the feasibility of methods of risk assessment to ecosystems associated to the presence or release of radioactive substances i environment. (N.C.)

  12. Research in radiation biology, in the environment, and in radiation protection at CRNL

    International Nuclear Information System (INIS)

    Marko, A.M.; Myers, D.K.; Ophel, I.L.; Cowper, G.; Newcombe, H.B.

    1978-01-01

    Research in radiation biology at CRNL is concerned with: evaluation of the effects of low doses of radiation upon humans and other living organisms; the development of new methods for detecting the effects of radiation exposure in large populations; the continued development of improved methods by which radiation levels can be measured accurately and reliably; and evaluation of the effects of nuclear power use upon the environment. The present report summarizes our background knowledge of radiation hazards and describes current research activities in Biology and Health Physics Division at CRNL. (author)

  13. Possible sources of radiation in indoor environment

    International Nuclear Information System (INIS)

    Djukanovic, M.

    1997-01-01

    More locations and building material will be needed to solve the housing needs, actually the future quantities will equal the total of all the previous building. And presently one quarter of the world population is already homeless. The development of human civilization in the new technological era goes on extremely quickly. In the search for new spaces, in the last decade of the 20th century, in town renovation planning the application of subterranean civil engineering is very popular. Below ground level, the new towns are built with many stories, with exclusively artificial light and artificial climate. There is not the slightest possibility of natural ventilation. These spaces have not been investigated as regards the contents of radon. Man is not adapted to spend most of the time in under artificial conditions. It is still to be discovered how it will affect humans and what is the degree of exposure to ionizing radiation in such conditions. It might be better to abandon underground construction before the adverse effects are proved. Previous mistakes in building must be overcome and new technologies applied as well as sustainable development in the future. (author)

  14. Variable Conductance Heat Pipe Radiators for Lunar and Martian Environments

    Science.gov (United States)

    Anderson, William G.; Ellis, Michael C.; Walker, Kara L.

    2009-03-01

    Long-term Lunar and Martian surface systems present challenges to thermal system design, including changes in thermal load, and large changes in the thermal environment between Lunar (or Martian) day and night. For example, the heat sink temperature at the Lunar equator can vary from 210 to 315 K. The radiator must be sized to reject the design power at the maximum temperature, but must also be able to accommodate both the changing heat sink temperature, as well as changes in power. Variable Conductance Heat Pipe (VCHP) radiators were examined for the main reactor of a fission surface power system, as well as the cavity cooling radiator. A VCHP radiator was designed for Lunar Equator that is capable of maintaining a 16 K temperature drop with a 4% addition to overall mass. Without the VCHP the radiator would experience a 43 K drop in temperature. This design is also capable of handling turndown on the power without an effect to the outlet temperature. At Shackleton Crater, the temperature drop for a conventional heat pipe radiator is small enough that a VCHP is not beneficial at constant power. However, a VCHP will allow turndown ratios of 5:1 or more. A conventional radiator can not be turned down more than 2:1, without valves to bypass part of the radiator. VCHPs are also easier to start than conventional radiators, since the gas-loading prevents sublimation from the evaporator when the condenser is frozen.

  15. Radiation exposure of airline crew members to the atmospheric ionizing radiation environment

    Energy Technology Data Exchange (ETDEWEB)

    De Angelis, G. E-mail: gianni.deangelis@iol.it; Caldora, M.; Santaquilani, M.; Scipione, R.; Verdecchia, A

    2001-06-01

    A study of radiation exposures in the ionizing radiation environment of the atmosphere is currently in progress for the Italian civil aviation flight personnel. After a description of the considered data sources/ the philosophy of the study is presented/ and an overview is given of the data processing with regard to flight routes/ the computational techniques for radiation dose evaluation along the flight paths and for the exposure matrix building/ along with an indication of the results that the study should provide.

  16. Utilization of SRNL-developed radiation-resistant polymer in high radiation environments

    Energy Technology Data Exchange (ETDEWEB)

    Skibo, A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-27

    The radiation-resistant polymer developed by the Savannah River National Laboratory is adaptable for multiple applications to enhance polymer endurance and effectiveness in radiation environments. SRNL offers to collaborate with TEPCO in evaluation, testing, and utilization of SRNL’s radiation-resistant polymer in the D&D of the Fukushima Daiichi NPS. Refinement of the scope and associated costs will be conducted in consultation with TECPO.

  17. Memory behaviour in a radiation environment

    International Nuclear Information System (INIS)

    Brucker, G.J.; Thurlow, L.

    1979-01-01

    Memory devices are often required for storage of data which must not be altered during a nuclear burst. If the properties of non-alterability and low power consumption during a standby mode of operation are combined, then the choice is narrowed down to static C-MOS bulk or silicon-on-sapphire (SOS) memories. Previous investigations have indicated that the SOS devices will achieve the maximum non-scrambling dose rate. However, it is interesting to determine the limitations of bulk as well as SOS devices for those programs where circumvention and refreshing of the memory is allowed. This article will present the results of an investigation of the characteristics of these memory types in a transient environment. (author)

  18. Gerald: a general environment for radiation analysis and design

    International Nuclear Information System (INIS)

    Boyle, Ch.; Oliveira, P.I.E. de; Oliveira, C.R.E. de; Adams, M.L.; Galan, J.M.

    2005-01-01

    Full text of publication follows: This paper describes the status of the GERALD interactive workbench for the analysis of radiation transport problems. GERALD basically guides the user through the various steps that are necessary to solve a radiation transport problem, and is aimed at education, research and industry. The advantages of such workbench are many: quality assurance of problem setup, interaction of the user with problem solution, preservation of theory and legacy research codes, and rapid proto-typing and testing of new methods. The environment is of general applicability catering for analytical, deterministic and stochastic analysis of the radiation problem and is not tied to one specific solution method or code. However, GERALD is being developed as a portable, modular, open source framework which renders itself quite naturally to the coupling of existing computational tools through specifically developed plug-ins. By offering a common route for setting up, solving and analyzing radiation transport problems GERALD offers the possibility of methods intercomparison and validation. Such flexible radiation transport environment will also facilitate the coupling of radiation physics methods to other physical phenomena and their application to other areas of application such as medical physics and the environment. (authors)

  19. Response of structural materials to radiation environments

    Energy Technology Data Exchange (ETDEWEB)

    Czajkowski, C.J.

    1997-12-01

    An evaluation of proton and neutron damage to aluminum, stainless steel, nickel alloys, and various aluminum alloys has been performed. The proton studies were conducted at energies of 200 MeV, 800 MeV, and 23.5 GeV. The proton studies consisted of evaluation and characterization of proton-irradiated window/target materials from accelerators and comparison to nonirradiated archival materials. The materials evaluated for the proton irradiations included 99.9999 wt% aluminum, 1100 aluminum, 5052 aluminum, 304 stainless steel, and inconel 718. The neutron damage research centered on 6061 T-6 aluminum which was obtained from a control-rod follower from the Brookhaven National Laboratory`s (BNL) High Flux Beam Reactor (HFBR). This material had received thermal neutron fluence up to {approximately}4 {times} 10{sup 23} n/cm{sup 2}. The possible effects of thermal-to-fast neutron flux ratios are discussed. The increases in tensile strength in the proton-irradiated materials is shown to be the result of atomic displacements. These displacements cause interstitials and vacancies which aggregate into defect clusters which result in radiation hardening of the materials. Production of gas (helium) in the grain boundaries of proton irradiated 99.9999 wt% aluminum is also discussed. The major factor contributing to the mechanical-property changes in the neutron-irradiated 6061 T-6 aluminum is the production of transmutation products formed by interactions of the aluminum with thermal neutrons. The metallurgical and mechanical-property evaluations for the research consisted of electron microscopy (both scanning and transmission), tensile testing, and microhardness testing.

  20. Role of natural radiation environment in earth sciences

    International Nuclear Information System (INIS)

    Vohra, K.G.

    1980-01-01

    Natural ionizing radiations play an important role in a wide spectrum of earth sciences, including meteorology, geophysics, hydrology, atmospheric physics, and atmospheric chemistry. The nature and distribution of ionizing radiation sources and natural radionuclides in the atmospheric environment are summarized. The present status of the use of natural radioactive tracers for atmospheric studies is discussed. The effect of ionization produced by natural radiation sources on atmospheric electricity, the relationship of electrical and meteorological variables, and the possible effects of man-made releases of 85 Kr are considered. Experimental evidence is presented for the production of condensation nuclei by the combined effects of radon and sulfur dioxide

  1. Interactive intervention planning in particle accelerator environments with ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Fabry, Thomas, E-mail: thomas.fabry@cern.ch [European Organization for Nuclear Research, CERN, CH-1211 Genève 23 (Switzerland); Vanherpe, Liesbeth [European Organization for Nuclear Research, CERN, CH-1211 Genève 23 (Switzerland); Baudin, Mathieu [European Organization for Nuclear Research, CERN, CH-1211 Genève 23 (Switzerland); LCPI, ENSAM ParisTech, 151 Boulevard de l' Hôpital, 75013 Paris (France); Theis, Chris [European Organization for Nuclear Research, CERN, CH-1211 Genève 23 (Switzerland); Braesch, Christian [SYMME, Université de Savoie, Polytech Annecy-Chambry, 5 chemin de Bellevue, 74944 Annecy le Vieux (France); Feral, Bruno [European Organization for Nuclear Research, CERN, CH-1211 Genève 23 (Switzerland)

    2013-04-21

    A core issue during the planning of a maintenance intervention in a facility with ionizing radiation is the minimization of the integrated equivalent dose contracted by the maintenance workers during the intervention. In this work, we lay down the concepts for intervention planning in an irradiated environment and present a new software program for intervention planning, which provides interactive visualization of facilities and radiation levels, as well as tools for interactive trajectory planning. The software includes automatic calculation of the expected integrated equivalent radiation dose contracted during an intervention.

  2. Interactive intervention planning in particle accelerator environments with ionizing radiation

    CERN Document Server

    Fabry, Thomas; Baudin, Mathieu; Theis, Chris; Braesch, Christian; Feral, Bruno

    2013-01-01

    A core issue during the planning of a maintenance intervention in a facility with ionizing radiation is the minimization of the integrated equivalent dose contracted by the maintenance workers during the intervention. In this work, we lay down the concepts for intervention planning in an irradiated environment and present a new software program for intervention planning, which provides interactive visualization of facilities and radiation levels, as well as tools for interactive trajectory planning. The software includes automatic calculation of the expected integrated equivalent radiation dose contracted during an intervention.

  3. Do we need radiation protection for the living environment?

    International Nuclear Information System (INIS)

    Hefner, A.; Voelkle, H.

    2003-01-01

    The protection of the living environment, i.e. non human species or non human organisms, is a condition for the long term human survival. This certainly is true also for radioactivity and ionizing radiation. The ICRP statement that fauna und flora are sufficiently protected if man is protected is valid in many cases but not in every one. The article gives some reflections on this subject from the point of view of practical radiation protection and some suggestions on how, if necessary, protection of the living environment could be put into practice. (orig.) [de

  4. Fifth International Symposium on the Natural Radiation Environment

    International Nuclear Information System (INIS)

    Porstendoerfer, J.; Swedjemark, G.A.; Baeverstam, U.; Lowder, W.M.; Miller, K.M.; Fisenne, I.M.

    1993-01-01

    The fifth International Symposium on the Natural Radiation Environment organized a series of tutorial sessions. One of the five major fields concerned with the radon issue. The tutorials dealt with important issues of the radon problem and covered the following aspects: Cosmic and Terrestrial Gamma Radiation Measurement, Properties and Behaviour of Radon and Thoron and Their Decay Products in the Air, Radon and Radon Daughters Metrology: Basic Aspects Long Lived Radionuclides in the Environment, in Food and in Human Beings, Design and Analysis of Radon Surveys with Epidemiological Utility

  5. Status Report of Simulated Space Radiation Environment Facility

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Phil Hyun; Nho, Young Chang; Jeun, Joon Pyo; Choi, Jae Hak; Lim, Youn Mook; Jung, Chan Hee; Jeon, Young Kyu

    2007-11-15

    The technology for performance testing and improvement of materials which are durable at space environment is a military related technology and veiled and securely regulated in advanced countries such as US and Russia. This core technology cannot be easily transferred to other country too. Therefore, this technology is the most fundamental and necessary research area for the successful establishment of space environment system. Since the task for evaluating the effects of space materials and components by space radiation plays important role in satellite lifetime extension and running failure percentage decrease, it is necessary to establish simulated space radiation facility and systematic testing procedure. This report has dealt with the status of the technology to enable the simulation of space environment effects, including the effect of space radiation on space materials. This information such as the fundamental knowledge of space environment and research status of various countries as to the simulation of space environment effects of space materials will be useful for the research on radiation hardiness of the materials. Furthermore, it will be helpful for developer of space material on deriving a better choice of materials, reducing the design cycle time, and improving safety.

  6. Contribution to developing the environment radiation protection methodology

    Energy Technology Data Exchange (ETDEWEB)

    Oudalova, A. [Institute of Atomic Power Engineering NRNU MEPhI (Russian Federation); Alexakhin, R.; Dubynina, M. [Russian Institute of Agricultural Radiology and Agroecology (Russian Federation)

    2014-07-01

    The environment sustainable development and biota protection, including the environment radiation protection are issues of nowadays interest in the society. An activity is ongoing on the development of a system of radiation protection for non-human biota. Anthropocentric and eco-centric principles are widely discussed. ICRP Publications 103, 108, 114 and many other reports and articles refer to the topic of environmental protection, reference animals and plants set, corresponding transfer parameters, dose models and derived consideration reference levels. There is still an open field for discussion of methods and approaches to get well-established procedure to assess environmental risks of radiation impacts to different organisms, populations and ecosystems. A huge work has been done by the ICRP and other organizations and research groups to develop and systematize approaches for this difficult subject. This activity, however, is not everywhere well-known and perceived, and more efforts are needed to bring ideas of eco-centric strategy in the environment radiation protection not only to public but to specialists in many countries as well. One of the main points of interest is an assessment of critical doses and doses rates for flora and fauna species. Some aspects of a possible procedure to find their estimates are studied in this work, including criteria for datasets of good quality, models of dose dependence, sensitivity of different umbrella endpoints and methods of original massive datasets treatment. Estimates are done based on information gathered in a database on radiation-induced effects in plants. Data on biological effects in plants (umbrella endpoints of reproductive potential, survival, morbidity, morphological, biochemical, and genetic effects) in dependence on dose and dose rates of ionizing radiation have been collected from reviewed publications and maintained in MS Access format. The database now contains about 7000 datasets and 25000 records

  7. Standardization of ionizing radiation in industry and environment

    International Nuclear Information System (INIS)

    1990-03-01

    In this account a new standardization system is described. This system is intended for the protection of environment, people and employees against the harmful consequences of ionizing radiation. This new system is based upon the actual knowledge of the harmful effects of ionizing radiation and joins to the starting points and objectives of the environment- and industry-protectional policies and is explained for both policies separately. The starting points and objectives are presented of the actual environment- and industry-protectional policies and of the radiation-protection policy pursued up till now. The harmful effects of radiation, the importance of the of the most recent scientific developments and the results of the investigation performed in the framework of this account, are described. Conclusions about these harmful affects are given. The systematics of the standardization are described. Subsequently are considered the radiation sources, their classification, the risk limits for regular situations and for large accidents, the justification principle and the ALARA-principle, emission- and product requirements, objectives for environment quality, standards for combat of the consequences of accidents, the policy with regard to 'building and dwelling' and finally standards for protection of employees. The consequences of the systematics of standardization, which are described in this account, are indicated for environment- as well as industry-protectional policy. Per radiation-source category the corresponding risks are indicated and at which term which continuation activities are necessary. The consequences for the set of instruments and some international aspects are considered. Finally the activity list gives a survey of the continuation activities and the terms at which these have to be carried out. (H.W.). 4 figs.; 1 tab

  8. Assessment of radiation awareness training in immersive virtual environments

    Science.gov (United States)

    Whisker, Vaughn E., III

    The prospect of new nuclear power plant orders in the near future and the graying of the current workforce create a need to train new personnel faster and better. Immersive virtual reality (VR) may offer a solution to the training challenge. VR technology presented in a CAVE Automatic Virtual Environment (CAVE) provides a high-fidelity, one-to-one scale environment where areas of the power plant can be recreated and virtual radiation environments can be simulated, making it possible to safely expose workers to virtual radiation in the context of the actual work environment. The use of virtual reality for training is supported by many educational theories; constructivism and discovery learning, in particular. Educational theory describes the importance of matching the training to the task. Plant access training and radiation worker training, common forms of training in the nuclear industry, rely on computer-based training methods in most cases, which effectively transfer declarative knowledge, but are poor at transferring skills. If an activity were to be added, the training would provide personnel with the opportunity to develop skills and apply their knowledge so they could be more effective when working in the radiation environment. An experiment was developed to test immersive virtual reality's suitability for training radiation awareness. Using a mixed methodology of quantitative and qualitative measures, the subjects' performances before and after training were assessed. First, subjects completed a pre-test to measure their knowledge prior to completing any training. Next they completed unsupervised computer-based training, which consisted of a PowerPoint presentation and a PDF document. After completing a brief orientation activity in the virtual environment, one group of participants received supplemental radiation awareness training in a simulated radiation environment presented in the CAVE, while a second group, the control group, moved directly to the

  9. General impact of robotics and automation in radiation environments

    International Nuclear Information System (INIS)

    Meghdari, A.; Salehi, M.

    1993-01-01

    Robotics and automation systems in nuclear environments require special design considerations. This paper presents an overview of selected robotic systems already designed and developed for use in nuclear applications at some U.S. laboratories. It will further emphasize on tasks identification, operational constraints, special considerations in materials selection, and a general guideline for robotic systems design in radiation environments. (author). 5 refs, 5 figs

  10. Optimization of radiation monitoring methods of environment

    International Nuclear Information System (INIS)

    Bondarkov, M.D.

    2012-01-01

    corresponding concentration radionuclides in the environment, and significantly reduce economic costs. The method of intra vital measurement of 90Sr in small animals opens up fundamentally new opportunities for researchers in radioecology and radiobiology

  11. Galileo Measurements of the Jovian Electron Radiation Environment

    Science.gov (United States)

    Garrett, H. B.; Jun, I.; Ratliff, J. M.; Evans, R. W.; Clough, G. A.; McEntire, R. W.

    2003-12-01

    The Galileo spacecraft Energetic Particle Detector (EPD) has been used to map Jupiter's trapped electron radiation in the jovian equatorial plane for the range 8 to 16 Jupiter radii (1 jovian radius = 71,400 km). The electron count rates from the instrument were averaged into 10-minute intervals over the energy range 0.2 MeV to 11 MeV to form an extensive database of observations of the jovian radiation belts between Jupiter orbit insertion (JOI) in 1995 and end of mission in 2003. These data were then used to provide differential flux estimates in the jovian equatorial plane as a function of radial distance (organized by magnetic L-shell position). These estimates provide the basis for an omni-directional, equatorial model of the jovian electron radiation environment. The comparison of these results with the original Divine model of jovian electron radiation and their implications for missions to Jupiter will be discussed. In particular, it was found that the electron dose predictions for a representative mission to Europa were about a factor of 2 lower than the Divine model estimates over the range of 100 to 1000 mils (2.54 to 25.4 mm) of aluminum shielding, but exceeded the Divine model by about 50% for thicker shielding for the assumed Europa orbiter trajectories. The findings are a significant step forward in understanding jovian electron radiation and represent a valuable tool for estimating the radiation environment to which jovian science and engineering hardware will be exposed.

  12. Wireless Communication Enhancement Methods for Mobile Robots in Radiation Environments

    CERN Document Server

    Nattanmai Parasuraman, Ramviyas; Ferre, Manuel

    In hostile environments such as in scientific facilities where ionising radiation is a dominant hazard, reducing human interventions by increasing robotic operations are desirable. CERN, the European Organization for Nuclear Research, has around 50 km of underground scientific facilities, where wireless mobile robots could help in the operation of the accelerator complex, e.g. in conducting remote inspections and radiation surveys in different areas. The main challenges to be considered here are not only that the robots should be able to go over long distances and operate for relatively long periods, but also the underground tunnel environment, the possible presence of electromagnetic fields, radiation effects, and the fact that the robots shall in no way interrupt the operation of the accelerators. Having a reliable and robust wireless communication system is essential for successful execution of such robotic missions and to avoid situations of manual recovery of the robots in the event that the robot runs ...

  13. Effects of radiation environment on reusable nuclear shuttle system

    Science.gov (United States)

    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.

  14. Adaptation of radiation shielding code to space environment

    International Nuclear Information System (INIS)

    Okuno, Koichi; Hara, Akihisa

    1992-01-01

    Recently, the trend to the development of space has heightened. To the development of space, many problems are related, and as one of them, there is the protection from cosmic ray. The cosmic ray is the radiation having ultrahigh energy, and there was not the radiation shielding design code that copes with cosmic ray so far. Therefore, the high energy radiation shielding design code for accelerators was improved so as to cope with the peculiarity that cosmic ray possesses. Moreover, the calculation of the radiation dose equivalent rate in the moon base to which the countermeasures against cosmic ray were taken was simulated by using the improved code. As the important countermeasures for the safety protection from radiation, the covering with regolith is carried out, and the effect of regolith was confirmed by using the improved code. Galactic cosmic ray, solar flare particles, radiation belt, the adaptation of the radiation shielding code HERMES to space environment, the improvement of the three-dimensional hadron cascade code HETCKFA-2 and the electromagnetic cascade code EGS 4-KFA, and the cosmic ray simulation are reported. (K.I.)

  15. High-Performance, Radiation-Hardened Electronics for Space Environments

    Science.gov (United States)

    Keys, Andrew S.; Watson, Michael D.; Frazier, Donald O.; Adams, James H.; Johnson, Michael A.; Kolawa, Elizabeth A.

    2007-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project endeavors to advance the current state-of-the-art in high-performance, radiation-hardened electronics and processors, ensuring successful performance of space systems required to operate within extreme radiation and temperature environments. Because RHESE is a project within the Exploration Technology Development Program (ETDP), RHESE's primary customers will be the human and robotic missions being developed by NASA's Exploration Systems Mission Directorate (ESMD) in partial fulfillment of the Vision for Space Exploration. Benefits are also anticipated for NASA's science missions to planetary and deep-space destinations. As a technology development effort, RHESE provides a broad-scoped, full spectrum of approaches to environmentally harden space electronics, including new materials, advanced design processes, reconfigurable hardware techniques, and software modeling of the radiation environment. The RHESE sub-project tasks are: SelfReconfigurable Electronics for Extreme Environments, Radiation Effects Predictive Modeling, Radiation Hardened Memory, Single Event Effects (SEE) Immune Reconfigurable Field Programmable Gate Array (FPGA) (SIRF), Radiation Hardening by Software, Radiation Hardened High Performance Processors (HPP), Reconfigurable Computing, Low Temperature Tolerant MEMS by Design, and Silicon-Germanium (SiGe) Integrated Electronics for Extreme Environments. These nine sub-project tasks are managed by technical leads as located across five different NASA field centers, including Ames Research Center, Goddard Space Flight Center, the Jet Propulsion Laboratory, Langley Research Center, and Marshall Space Flight Center. The overall RHESE integrated project management responsibility resides with NASA's Marshall Space Flight Center (MSFC). Initial technology development emphasis within RHESE focuses on the hardening of Field Programmable Gate Arrays (FPGA)s and Field Programmable Analog

  16. Protection of the environment from ionising radiation: ethical issues

    International Nuclear Information System (INIS)

    Oughton, Deborah

    2003-01-01

    The paper identifies some of the main ethical issues concerning the protection of the environment from radiation and suggests ways in which ethics can aid in developing a system of protection. After a presentation of background on ethical theory and environmental ethics, three main issues related to environmental protection are discussed: First, the question of valuing the environment and implications for the definition of harm and monetary valuation of environmental goods; second, difficulties with scientific uncertainty and applications of the precautionary principle; and third, issues concerned with the distribution of risk and its relevance fo participation in decision-making. In summary, the paper argues that there are strong ethical grounds to provide for the protection of the environment and that, all other things being equal, there is no reason to treat ionising radiation differently to other environmental stressors

  17. Protection of the environment from ionising radiation: ethical issues.

    Science.gov (United States)

    Oughton, Deborah

    2003-01-01

    The paper identifies some of the main ethical issues concerning the protection of the environment from radiation and suggests ways in which ethics can aid in developing a system of protection. After a presentation of background on ethical theory and environmental ethics, three main issues related to environmental protection are discussed: First, the question of valuing the environment and implications for the definition of harm and monetary valuation of environmental goods; second, difficulties with scientific uncertainty and applications of the precautionary principle; and third, issues concerned with the distribution of risk and its relevance for participation in decision-making. In summary, the paper argues that there are strong ethical grounds to provide for the protection of the environment and that, all other things being equal, there is no reason to treat ionising radiation differently to other environmental stressors. Copyright 2002 Elsevier Science Ltd.

  18. Travel for the 2004 American Statistical Association Biannual Radiation Meeting: "Radiation in Realistic Environments: Interactions Between Radiation and Other Factors

    Energy Technology Data Exchange (ETDEWEB)

    Brenner, David J.

    2009-07-21

    The 16th ASA Conference on Radiation and Health, held June 27-30, 2004 in Beaver Creek, CO, offered a unique forum for discussing research related to the effects of radiation exposures on human health in a multidisciplinary setting. The Conference furnishes investigators in health related disciplines the opportunity to learn about new quantitative approaches to their problems and furnishes statisticians the opportunity to learn about new applications for their discipline. The Conference was attended by about 60 scientists including statisticians, epidemiologists, biologists and physicists interested in radiation research. For the first time, ten recipients of Young Investigator Awards participated in the conference. The Conference began with a debate on the question: “Do radiation doses below 1 cGy increase cancer risks?” The keynote speaker was Dr. Martin Lavin, who gave a banquet presentation on the timely topic “How important is ATM?” The focus of the 2004 Conference on Radiation and Health was Radiation in Realistic Environments: Interactions Between Radiation and Other Risk Modifiers. The sessions of the conference included: Radiation, Smoking, and Lung Cancer Interactions of Radiation with Genetic Factors: ATM Radiation, Genetics, and Epigenetics Radiotherapeutic Interactions The Conference on Radiation and Health is held bi-annually, and participants are looking forward to the 17th conference to be held in 2006.

  19. The radiation environment in Sweden; Straalmiljoen i Sverige

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Paal; Carlsson, Monica; Falk, Rolf; Hubbard, Lynn; Leitz, Wolfram; Mjoenes, Lars; Moere, Hans; Nyblom, Leif; Soederman, Ann-Louise; Yuen Lasson, Katarina; Aakerblom, Gustav; Oehlen, Elisabeth

    2007-01-15

    The report describes, and reports data from, the monitoring of the radiation environment which has been conducted in Sweden since the 1950s. Average doses to the general public as well as to special groups of the public are also reported. Environmental monitoring concerning radiation has to a great extent focused on deposition and occurrence of radioactive elements originating from the atmospheric nuclear weapon tests and the Chernobyl accident. The average dose from {sup 137}Cs is very low, although it is somewhat higher in the group 'reindeer herders'. Surveys of naturally occurring radioactive elements in soil, drinking water and indoor air show that radiation from soil and building materials constitutes, besides medical use of radiation, the main part of the average total dose to the population. The dose from drinking water from drilled wells or from radon in indoor air may dominate the total dose in certain cases. Smoking increases the risk of radon considerably. UV-radiation has increased with 10 percent over the last 22 years at the location of the monitoring station. This is mainly explained by a decreased cloudiness. The exposure for UV is however more dependent on behaviour, and approximately 25 percent of the total exposure takes place abroad. Presently there are no time series concerning electromagnetic fields in the outdoor environment. However, measurements indicate levels well below the reference values.

  20. Modeling of the Martian environment for radiation analysis

    International Nuclear Information System (INIS)

    De Angelis, G.; Wilson, J.W.; Clowdsley, M.S.; Qualls, G.D.; Singleterry, R.C.

    2006-01-01

    A model for the radiation environment to be found on the planet Mars due to Galactic Cosmic Rays (GCR) has been developed. Solar modulated primary particles rescaled for conditions at Mars are transported through the Martian atmosphere down to the surface, with altitude and backscattering patterns taken into account. The altitude to compute the atmospheric thickness profile has been determined by using a model for the topography based on the data provided by the Mars Orbiter Laser Altimeter (MOLA) instrument on board the Mars Global Surveyor (MGS) spacecraft. The Mars surface composition has been modeled based on averages over the measurements obtained from orbiting spacecraft and at various landing sites, taking into account the possible volatile inventory (e.g. CO 2 and H 2 O ices) along with its time variations throughout the Martian year. The Mars Radiation Environment Model has been made available worldwide through the Space Ionizing Radiation Effects and Shielding Tools (SIREST) website, a project of NASA Langley Research Center. This site has been developed to provide the scientific and engineering communities with an interactive site containing a variety of environmental models, shield evaluation codes, and radiation response models to allow a thorough assessment of ionizing radiation risk for current and future space missions

  1. Remembering Leo Kadanoff

    Indian Academy of Sciences (India)

    Everyone gathered at the Monday bag-lunch seminar series Leo started. He was already a celebrity with ... the world and presented bag-lunch seminars in addition to their more formal lecture-duties at the institute ... The emergence of the now famous Chicago school in statistical and soft matter physics took place after I left ...

  2. Leo Meyer / Villem Reiman

    Index Scriptorium Estoniae

    Reiman, Villem

    2008-01-01

    Prof. dr. phil. Leo Meyer (03.07.1830-24.05.1910), keeleteadlane, Tartu ja Göttingeni ülikooli ja võrdleva keeleteaduse õppejõud, Eesti Kirjanduse Seltsi kauaaegne esimees ja esimene auliige. Varem ilm.: Eesti Kirjandus, 1910, nr. 9, lk. 389-393

  3. Basic mechanisms of radiation effects in the natural space radiation environment

    Energy Technology Data Exchange (ETDEWEB)

    Schwank, J.R.

    1994-06-01

    Four general topics are covered in respect to the natural space radiation environment: (1) particles trapped by the earth`s magnetic field, (2) cosmic rays, (3) radiation environment inside a spacecraft, (4) laboratory radiation sources. The interaction of radiation with materials is described by ionization effects and displacement effects. Total-dose effects on MOS devices is discussed with respect to: measurement techniques, electron-hole yield, hole transport, oxide traps, interface traps, border traps, device properties, case studies and special concerns for commercial devices. Other device types considered for total-dose effects are SOI devices and nitrided oxide devices. Lastly, single event phenomena are discussed with respect to charge collection mechanisms and hard errors. (GHH)

  4. Ionizing Radiation Measurement Solution in a Hospital Environment

    Directory of Open Access Journals (Sweden)

    Antonio-Javier Garcia-Sanchez

    2018-02-01

    Full Text Available Ionizing radiation is one of the main risks affecting healthcare workers and patients worldwide. Special attention has to be paid to medical staff in the vicinity of radiological equipment or patients undergoing radioisotope procedures. To measure radiation values, traditional area meters are strategically placed in hospitals and personal dosimeters are worn by workers. However, important drawbacks inherent to these systems in terms of cost, detection precision, real time data processing, flexibility, and so on, have been detected and carefully detailed. To overcome these inconveniences, a low cost, open-source, portable radiation measurement system is proposed. The goal is to deploy devices integrating a commercial Geiger-Muller (GM detector to capture radiation doses in real time and to wirelessly dispatch them to a remote database where the radiation values are stored. Medical staff will be able to check the accumulated doses first hand, as well as other statistics related to radiation by means of a smartphone application. Finally, the device is certified by an accredited calibration center, to later validate the entire system in a hospital environment.

  5. Combined injury syndrome in space-related radiation environments

    Science.gov (United States)

    Dons, R. F.; Fohlmeister, U.

    The risk of combined injury (CI) to space travelers is a function of exposure to anomalously large surges of a broad spectrum of particulate and photon radiations, conventional trauma (T), and effects of weightlessness including decreased intravascular fluid volume, and myocardial deconditioning. CI may occur even at relatively low doses of radiation which can synergistically enhance morbidity and mortality from T. Without effective countermeasures, prolonged residence in space is expected to predispose most individuals to bone fractures as a result of calcium loss in the microgravity environment. Immune dysfunction may occur from residence in space independent of radiation exposure. Thus, wound healing would be compromised if infection were to occur. Survival of the space traveler with CI would be significantly compromised if there were delays in wound closure or in the application of simple supportive medical or surgical therapies. Particulate radiation has the potential for causing greater gastrointestinal injury than photon radiation, but bone healing should not be compromised at the expected doses of either type of radiation in space.

  6. RADIATION ENVIRONMENT, ORGANIZATION AND PROVIDING OF POPULATION RADIATION PROTECTION CONTROL IN ST. PETBURG

    Directory of Open Access Journals (Sweden)

    I. A. Rakitin

    2008-01-01

    Full Text Available The article presents the analysis of radiation environment and work experience of Rospotrebnadzor Administration in St. Petersburg in the field of organizing of population radiation protection control and interaction with the local government executive bodies. It shows the level and structure of the city population collective doses from the main dose forming ionizing irradiation sources. It emphasizes the integrated method of solving the population exposure limitation issues based on the results of radiation-hygienic passport system and on the data from Uniform State System for Doses Control and Registration. The evaluation of the work being carried out is given.

  7. Astrobiological Effects of Stellar Radiation in Circumstellar Environments

    Science.gov (United States)

    Cuntz, Manfred; Gurdemir, Levent; Guinan, Edward F.; Kurucz, Robert L.

    2006-10-01

    The centerpiece of all life on Earth is carbon-based biochemistry. Previous scientific research has suggested that biochemistry based on carbon may also play a decisive role in extraterrestrial life forms, i.e., alien life outside of Earth, if existent. In the following, we explore if carbon-based macromolecules (such as DNA) in the environments of stars other than the Sun are able to survive the effects of energetic stellar radiation, such as UV-C in the wavelength band between 200 and 290 nm. We focus on main-sequence stars akin to the Sun, but of hotter (F-type stars) and cooler (K- and M-type stars) surface temperature. Emphasis is placed on investigating the radiative environment in stellar habitable zones (HZs). Stellar habitable zones have an important relevance in astrobiology because they constitute circumstellar regions in which a planet of suitable size can have surface temperatures for water to exist in liquid form.

  8. A virtual environment for medical radiation collaborative learning.

    Science.gov (United States)

    Bridge, Pete; Trapp, Jamie V; Kastanis, Lazaros; Pack, Darren; Parker, Jacqui C

    2015-06-01

    A software-based environment was developed to provide practical training in medical radiation principles and safety. The Virtual Radiation Laboratory application allowed students to conduct virtual experiments using simulated diagnostic and radiotherapy X-ray generators. The experiments were designed to teach students about the inverse square law, half value layer and radiation protection measures and utilised genuine clinical and experimental data. Evaluation of the application was conducted in order to ascertain the impact of the software on students' understanding, satisfaction and collaborative learning skills and also to determine potential further improvements to the software and guidelines for its continued use. Feedback was gathered via an anonymous online survey consisting of a mixture of Likert-style questions and short answer open questions. Student feedback was highly positive with 80 % of students reporting increased understanding of radiation protection principles. Furthermore 72 % enjoyed using the software and 87 % of students felt that the project facilitated collaboration within small groups. The main themes arising in the qualitative feedback comments related to efficiency and effectiveness of teaching, safety of environment, collaboration and realism. Staff and students both report gains in efficiency and effectiveness associated with the virtual experiments. In addition students particularly value the visualisation of "invisible" physical principles and increased opportunity for experimentation and collaborative problem-based learning. Similar ventures will benefit from adopting an approach that allows for individual experimentation while visualizing challenging concepts.

  9. Predicted radiation environment of the Saturn baseline diode

    International Nuclear Information System (INIS)

    Halbleib, J.A.; Lee, J.R.

    1987-09-01

    Coupled electron/photon Monte Carlo radiation transport was used to predict the radiation environment of the Saturn accelerator for the baseline diode design. The x-ray output has been calculated, as well as energy deposition in CaF 2 thermoluminescent dosimetry and silicon. It is found that the design criteria for the radiation environment will be met and that approximately 10 kJ of x rays will be available for simulation experiments, if the diode provides a nominal beam of 2.0-MeV electrons for 20 ns with a peak current of 12.5 MA. The penalty in dose and x-ray output for operating below the nominal energy in order to obtain a softer spectrum is quantified. The penalty for using excessive electron equilibration in the standard packaging of the thermoluminescent dosimeters is shown to be negligible. An intrinsic lack of electron equilibration for silicon elements of components and subsystems is verified for Saturn environments, demonstrating the ambiguity of design criteria based on silicon deposition. Validation of an efficient next-event-estimator method for predicting energy deposition in equilibrated detectors/dosimetry is confirmed. Finally, direct-electron depositions in excess of 1 kJ/g are shown to be easily achievable. 34 refs., 30 figs

  10. The radiation environment in underground workplaces of the LHC

    CERN Document Server

    Theis, C; Kindl, Peter

    2007-01-01

    Active dose-monitoring of workplaces is crucial in order to operate a high-energy particle accelerator safely. As the mixed radiation fields that are expected in the environment of the Large Hadron Collider (LHC) are very different from standard use-cases like in nuclear power plants, it is of highest importance to characterize and calibrate radiation monitoring equipment appropriately for their use in high energy mixed radiation fields. Due to their sensitivity to different particle types over a larger energy range high-pressure ionization chambers have already been used at CERN and they are foreseen to be included within the radiation monitoring system of the LHC. In the framework of this thesis a new method was developed which allows for appropriate field-specific calibration of these detectors using Monte Carlo simulations. Therefore, the application of common 238Pu-Be source based calibration in mixed radiation fields was studied and compared to more accurate field specific calibration based on FLUKA Mon...

  11. Background radiation dose of dumpsites in Ota and Environs

    Science.gov (United States)

    Usikalu, M. R.; Ola, O. O.; Achuka, J. A.; Babarimisa, I. O.; Ayara, W. A.

    2017-05-01

    In-situ measurement of background radiation dose from selected dumpsites in Ota and its environs was done using Radialert Nuclear Radiation Monitor (Digilert 200). Ten measurements were taken from each dumpsite. The measured background radiation range between 0.015 mRhr-1 for AOD and 0.028 mRhr-1 for SUS dumpsites. The calculated annual equivalent doses vary between 1.31 mSvyr-1 for AOD and 2.28 mSv/yr for SUS dumpsites. The air absorbed dose calculated ranged from 150 nGyhr-1 to 280 nGy/hr for AOD and SUS dumpsites respectively with an average value of 217 nGyhr-1 for all the locations. All the estimated parameters were higher than permissible limit set for background radiation for the general public. Conclusively, the associated challenge and radiation burden posed by the wastes on the studied locations and scavengers is high. Therefore, there is need by the regulatory authorities to look into the way and how waste can be properly managed so as to alleviate the effects on the populace leaving and working in the dumpsites vicinity.

  12. Vegetative development and production of essential oil of Patchouli under radiation levels and GA3 applicationDesenvolvimento vegetativo e produção de óleo essencial de patchouli, sombreamento e aplicação de GA3

    Directory of Open Access Journals (Sweden)

    Rafaellen Caroline Storck

    2013-10-01

    Full Text Available Pogostemon cablin Benth. has economical importance due to the essential oil which is used in the pharmaceutical and perfume industries. Among the environment factors, the radiation is extremely important for plant development and its limitation can result on decrease of yield. The application of gibberellins promotes the cellular elongation resulting on increase of plant height. Therefore, the radiation level and plant growth regulators can indirectly affect the essential oil production due its accumulation in the biomass. The objective of this work was to evaluate vegetative development and essential oil production of patchouli under shading and after GA3 application. The experimental design was completely randomized in a 2 x 3 factorial arrangement comparing shading levels (0, 54, and 77% with or without GA3 application (200 mg.L-1. The GA3 was applied 30 days after planting. The plants showed a superior height under 77% of shading and with GA3 at 120 days after planting. The leaf number was superior on plants developed under no radiation limitation and after 75 days of GA3 application. The stem number also was significantly superior under no shading and without GA3. The application of the growth regulator at 75 days also promoted great stem number of branches with 54% of shading. However, treatment with GA3 increased essential oil yield and productivity and greater yield in P. Cablin under shading conditions. The growth regulator can be used to compensate the negative effect of lower radiation levels. This is of great interest for patchouli cultivation as the GA3 application allows to increase plant population and, consequently, biomass and essential oil production.Pogostemon cablin Benth. possui importância econômica devido à produção de óleo essencial utilizado pelas indústrias farmacêuticas e de perfumarias. Dentre os fatores ambientais, a radiação é de extrema importância no desenvolvimento das plantas, onde sua limita

  13. Radiation exposure of airline crew members to the atmospheric ionizing radiation environment

    International Nuclear Information System (INIS)

    Angelis, G. De; Ballard, T.; Lagorio, S.; Verdecchia, A.

    2000-01-01

    All risk assessment techniques for possible health effects from low dose rate radiation exposure should combine knowledge both of the radiation environment and of the biological response, whose effects (e.g. carcinogenesis) are usually evaluated through mathematical models and/or animal and cell experiments. Data on human exposure to low dose rate radiation exposure and its effects are not readily available, especially with regards to stochastic effects, related to carcinogenesis and therefore to cancer risks, for which the event probability increases with increasing radiation exposure. The largest source of such data might be airline flight personnel, if enrolled for studies on health effects induced by the cosmic-ray generated atmospheric ionizing radiation, whose total dose, increasing over the years, might cause delayed radiation-induced health effects, with the high-LET and highly ionizing neutron component typical of atmospheric radiation. In 1990 flight personnel has been given the status of 'occupationally exposed to radiation' by the International Commission for Radiation Protection (ICRP), with a received radiation dose that is at least twice larger than that of the general population. The studies performed until now were limited in scope and cohort size, and moreover no information whatsoever on radiation occupational exposure (e.g. dose, flight hours, route haul, etc.) was used in the analysis, so no correlation has been until now possible between atmospheric ionizing radiation and (possibly radiation-induced) observed health effects. Our study addresses the issues, by considering all Italian civilian airline flight personnel, both cockpit and cabin crew members, with about 10,000 people selected, whose records on work history and actual flights (route, aircraft type, date, etc. for each individual flight for each person where possible) are considered. Data on actual flight routes and profiles have been obtained for the whole time frame. The actual dose

  14. Analysis of China's radiation environment monitoring standard system

    International Nuclear Information System (INIS)

    Lu Weiwei; Yue Huiguo; Yuan Zhilun; Yu Zhengwei; Huang Donghui; Wu Yongle

    2014-01-01

    In order to establish and improve the radiation environment monitoring standard system, to provide technical support for the radiation environment monitoring system, this work first retrieve the radiation environment monitoring standards, and clear the domestic status of the radiation environment monitoring standards. According to the Environmental Protection issued by the Ministry of the radiation environment monitoring technology specification '(HJ/T 61-2001), the radiation environment monitoring program (Provisional)' (Central Office (2003) No.56), and the radiation environment monitoring capacity assessment program (Environmental Protection management Division of the Department of nuclear safety, January 2011), environmental Protection Department of the relevant documents and other relevant information, the radiation environment monitoring standards and methods have been accessed, to find the missing items and issues proposed revision of the system requirements. Summarizing radiation environment monitoring national standards, standards of environmental protection industry, the nuclear industry standard, there are 28 standard missing items need to the health industry standards, inspection and quarantine industry standards, a total of 145 of these standards of environmental radiation monitoring, radiation monitoring of pollution sources, emergency response and early warning and monitoring from a management and technology meet the basic needs of the radiation environment monitoring. Research found that the standards in the revised 57 and in the formulation of 47, develop. After the revision of China's standards system will be further improved. The radiation environment monitoring work will be further strengthened. (authors)

  15. Petróleo

    Directory of Open Access Journals (Sweden)

    Celso Fernando Lucchesi

    1998-08-01

    Full Text Available COM MENOS DE 50 anos de atividade empresarialmente organizada a exploração de petróleo no Brasil encontra-se em fase de mudança com a aprovação, em 1997, da nova legislação do setor de petróleo. Descreve-se neste trabalho o período pré-Petrobras (1858 a 1953 e a exclusividade da Petrobras (1954 a 1997 que resultou no expressivo volume de reservas de petróleo no país, da ordem de 17 bilhões de barris de óleo equivalente no final de 1997. Projetos de produção já iniciados elevarão a produção a mais de 1,5 milhão de barris de óleo por dia no início do novo século. O gás natural crescerá rapidamente sua participação na matriz energética a partir de 1999. Com a instalação da Agência Nacional de Petróleo (ANP inicia-se uma nova fase, sendo esta responsável pela atração de novos investimentos na busca de novas reservas nas bacias sedimentares brasileiras, cujo potencial é ainda significativo. Diversas empresas internacionais deverão estar operando no país no curto prazo, inicialmente associadas à Petrobras. O modelo adotado para as atividades de exploração e produção no país é o de concessão. A atividade no Brasil nesta área dependerá do regime fiscal que vier a ser implantado.THE APPROVAL OF the new Petroleum Law in 1997 proposed a dramatic change in the activities of petroleum exploration in Brazil after almost fifty years of its initial entrepreneurual organization, represented by the creation of Petrobras, in 1953. In this work two important periods are described: the pre-Petrobras period (1858 to 1953 and the period when Petrobras acted alone in the oil business (1954 to 1997. During the last one, significant results were achieved. The amount of reserves reached 17 billion barrels of oil equivalent and were made available to the country at the end of 1997. Production projects already in place or under development will raise Brazilian daily production to levels of 1.5 million barrels of oil per day

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

    Science.gov (United States)

    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.

  17. Optical fibres in the radiation environment of CERN

    Science.gov (United States)

    Guillermain, E.

    2017-11-01

    kGy). Nevertheless, the conventional optical fibres must be carefully qualified as a spread in RIA of factor 10 is observed among optical fibres of different types and dopants. In higher radiation areas, special radiation resistant optical fibres are installed. For total dose above 1 kGy, the RIA of these special optical fibres is at least 10 times lower than the conventional optical fibres RIA at same irradiation conditions. 2400 km of these special radiation resistant optical fibres were recently procured at CERN. As part of this procurement process, a quality assurance plan including the irradiation testing of all 65 produced batches was set up. This presentation will review the selection process of the appropriate optical fibre types to be installed in the radiation environment of CERN. The methodology for choosing the irradiation parameters for the laboratory tests will be discussed together with an overview of the RIA of different optical fibre types under several irradiation conditions.

  18. Radiation Hardened Electronics Destined For Severe Nuclear Reactor Environments

    Energy Technology Data Exchange (ETDEWEB)

    Holbert, Keith E. [Arizona State Univ., Tempe, AZ (United States); Clark, Lawrence T. [Arizona State Univ., Tempe, AZ (United States)

    2016-02-19

    Post nuclear accident conditions represent a harsh environment for electronics. The full station blackout experience at Fukushima shows the necessity for emergency sensing capabilities in a radiation-enhanced environment. This NEET (Nuclear Energy Enabling Technologies) research project developed radiation hardened by design (RHBD) electronics using commercially available technology that employs commercial off-the-shelf (COTS) devices and present generation circuit fabrication techniques to improve the total ionizing dose (TID) hardness of electronics. Such technology not only has applicability to severe accident conditions but also to facilities throughout the nuclear fuel cycle in which radiation tolerance is required. For example, with TID tolerance to megarads of dose, electronics could be deployed for long-term monitoring, inspection and decontamination missions. The present work has taken a two-pronged approach, specifically, development of both board and application-specific integrated circuit (ASIC) level RHBD techniques. The former path has focused on TID testing of representative microcontroller ICs with embedded flash (eFlash) memory, as well as standalone flash devices that utilize the same fabrication technologies. The standalone flash devices are less complicated, allowing better understanding of the TID response of the crucial circuits. Our TID experiments utilize biased components that are in-situ tested, and in full operation during irradiation. A potential pitfall in the qualification of memory circuits is the lack of rigorous testing of the possible memory states. For this reason, we employ test patterns that include all ones, all zeros, a checkerboard of zeros and ones, an inverse checkerboard, and random data. With experimental evidence of improved radiation response for unbiased versus biased conditions, a demonstration-level board using the COTS devices was constructed. Through a combination of redundancy and power gating, the demonstration

  19. Mars Surface Ionizing Radiation Environment: Need for Validation

    Science.gov (United States)

    Wilson, J. W.; Kim, M. Y.; Clowdsley, M. S.; Heinbockel, J. H.; Tripathi, R. K.; Singleterry, R. C.; Shinn, J. L.; Suggs, R.

    1999-01-01

    Protection against the hazards from exposure to ionizing radiation remains an unresolved issue in the Human Exploration and Development of Space (HEDS) enterprise [1]. The major uncertainty is the lack of data on biological response to galactic cosmic ray (GCR) exposures but even a full understanding of the physical interaction of GCR with shielding and body tissues is not yet available and has a potentially large impact on mission costs. "The general opinion is that the initial flights should be short-stay missions performed as fast as possible (so-called 'Sprint' missions) to minimize crew exposure to the zero-g and space radiation environment, to ease requirements on system reliability, and to enhance the probability of mission success." The short-stay missions tend to have long transit times and may not be the best option due to the relatively long exposure to zero-g and ionizing radiation. On the other hand the short-transit missions tend to have long stays on the surface requiring an adequate knowledge of the surface radiation environment to estimate risks and to design shield configurations. Our knowledge of the surface environment is theoretically based and suffers from an incomplete understanding of the physical interactions of GCR with the Martian atmosphere, Martian surface, and intervening shield materials. An important component of Mars surface robotic exploration is the opportunity to test our understanding of the Mars surface environment. The Mars surface environment is generated by the interaction of Galactic Cosmic Rays (GCR) and Solar Particle Events (SPEs) with the Mars atmosphere and Mars surface materials. In these interactions, multiple charged ions are reduced in size and secondary particles are generated, including neutrons. Upon impact with the Martian surface, the character of the interactions changes as a result of the differing nuclear constituents of the surface materials. Among the surface environment are many neutrons diffusing from

  20. Effect of ionizing radiation on the waste package environment

    Energy Technology Data Exchange (ETDEWEB)

    Reed, D.T. [Argonne National Lab., IL (USA); Van Konynenburg, R.A. [Lawrence Livermore National Lab., CA (USA)

    1991-05-01

    The radiolytic production of nitrogen oxides, nitrogen acids and ammonia are discussed in relation to the expected environment in a high-level waste repository that may be constructed at the Yucca Mountain site if it is found to be suitable. Both literature data and repository-relevant data are summarized for air-water vapor systems. The limiting cases of a dry air and a pure water vapor gas phase are also discussed. Design guidelines and recommendations, based solely on the potential consequence of radiation enhancement of corrosion, are given. 13 refs., 5 figs., 1 tab.

  1. Radiation exposure of man in the indoor environment

    International Nuclear Information System (INIS)

    Steinhaeusler, F.; Pohl, E.

    1982-01-01

    Indoor exposure of man represents the major component of the dose from the natural radiation environment (NRE). The different sources of the NRE and their complex superposition are discussed. Due to the use of radiologically disadvantageous material in or near the building, radon-rich tap water, specific architectural styles and decreased ventilation rates NRE-levels indoors have been found to even exceed the upper limit for professional exposure. The inadequacy of the existing international regulatory framework and specific local problems resulted in the establishment of national exposure limits. In general, no remedial action is recommended at levels below 50 μR/h for external gamma radiation, 10 mWL for internal radon daughter exposure. Several technical countermeasures reducing indoor gamma dose rates and radon levels have been developed for existing buildings. However, the use of some of the techniques is limited due to low cost-effectiveness or lack of long-term stability. Different techniques in order to achieve low indoor exposures for new buildings and financial aspects associated the application of radiation protection concepts are discussed

  2. Radiation environment impact assessment of field radionuclide migration test

    International Nuclear Information System (INIS)

    Guo Zede; Han Jingyin; Wang Zhiming; Han Bianlian; Jin Xiaojuan; Yan Yukui

    2000-01-01

    A field radionuclide migration test was carried out under natural and sprinkling conditions at CIRP's Field Test Site. Environment monitoring results indicated that the test did not cause any change of radiation environment quality in and around the test area. After test, contaminated soil in each test pits was retrieved and transported back in CIRP for other research work. All recovery rates of 60 Co, 134 Cs in each test pits is more than 99.99%. After recovery, residual 3 H in former natural test pits is kept in shallow soil and subjected to be evaporated into atmosphere; residual 3 H in other test pits after stopping sprinkling is kept in deep position of aerated zone and can not reach aqueous layer before fully decay. Since its short half life, 85 Sr had nearly fully decayed when the test was finished. Retrieving contaminated soil eliminates possibility of any incidents in future. It is concluded from the point of both total amount and concentrations, that residual radionuclides at the field test site can not cause any unacceptable effect on human and the environment

  3. Radiation protection for humans and environment. 50 years competence in the professional association

    International Nuclear Information System (INIS)

    Bucher, Benno; Wilhelm, Christoph

    2016-01-01

    The conference proceedings of the IRPA (International radiation protection association) annual meeting 2016 contain the contribution of invited referents, other contributions and poster contributions concerning radiation protection in nuclear facilities, radiation protection of the public and environment, radioactive waste management, uranium mining, environmental monitoring, natural radioactivity, and radiation protection laws and regulations.

  4. Coherent and radiative couplings through two-dimensional structured environments

    Science.gov (United States)

    Galve, F.; Zambrini, R.

    2018-03-01

    We study coherent and radiative interactions induced among two or more quantum units by coupling them to two-dimensional (2D) lattices acting as structured environments. This model can be representative of atoms trapped near photonic crystal slabs, trapped ions in Coulomb crystals, or to surface acoustic waves on piezoelectric materials, cold atoms on state-dependent optical lattices, or even circuit QED architectures, to name a few. We compare coherent and radiative contributions for the isotropic and directional regimes of emission into the lattice, for infinite and finite lattices, highlighting their differences and existing pitfalls, e.g., related to long-time or large-lattice limits. We relate the phenomenon of directionality of emission with linear-shaped isofrequency manifolds in the dispersion relation, showing a simple way to disrupt it. For finite lattices, we study further details such as the scaling of resonant number of lattice modes for the isotropic and directional regimes, and relate this behavior with known van Hove singularities in the infinite lattice limit. Furthermore, we export the understanding of emission dynamics with the decay of entanglement for two quantum, atomic or bosonic, units coupled to the 2D lattice. We analyze in some detail completely subradiant configurations of more than two atoms, which can occur in the finite lattice scenario, in contrast with the infinite lattice case. Finally, we demonstrate that induced coherent interactions for dark states are zero for the finite lattice.

  5. Fibre optics compatibility with radiative environment inside PWR containment

    International Nuclear Information System (INIS)

    Breuze, G.; Jucker, P.; Serre, J.

    1993-01-01

    Fibre optic links operating with multiplexed sensors data are potentially attractive for nuclear power plant applications. It hence became essential to test for radiation vulnerability not only transmission support -fibres- but also fibre-end electro-optical components which could be exposed to hostile environment, perhaps in worse conditions than fibres. Present paper gives results of multimode silica-based fibre behaviour during long-term steady-state low dose-rate gamma ray exposure - one year under 0.1 to 0.2 Gy/h. Studies concerned radiation-induced loss (ΔL) measurement of eight different commercially available fibres and bit error-rate (BER) recording of four 1 100 m length data links operating with a 100 m part exposed to gamma-rays. Main result is the good behaviour of pure silica-core fibres, especially a step-index polymer-clad fibre transmitting 850 nm light but also a graded-index fluorine-clad fibre for 1 300 nm window. Mean ΔL values are respectively 3 dB/km and 4.5 dB/km at the exposure end. Complementary result is no influence of gamma-ray exposure upon data link initial 10 -9 BER. (authors). 9 figs., 7 tabs., 26 refs

  6. Íleo biliar

    OpenAIRE

    Allan Pérez-Baltodano; Marcela Bermúdez-Coto; Madelein Centeno-Rodríguez; William Vargas-Alpízar

    2005-01-01

    El íleo biliar es una entidad clínica difícil de diagnosticar que se produce como resultado de una comunicación anormal entre la vía biliar y el tubo digestivo, con la consiguiente evacuación del cálculo e impactación del mismo distalmente hasta que se presenta como un cuadro de obstrucción intestinal. Reportamos el caso de un paciente de 47 años de edad, sin antecedentes médicos ni quirúrgicos de importancia, que ingresó al servicio de emergencias quirúrgicas con un abdomen agudo, caracteriz...

  7. Fifth international symposium on the natural radiation environment (NRE - V). Book of abstracts

    International Nuclear Information System (INIS)

    1991-01-01

    Most of the 219 contributions Are on radon (to a much lesser extent: thoron) and its daughter products in dwellings and in the environment; on corresponding measuring instruments and - methods; on measurements done; and on radiation doses to professional workers and to the public. The section heading give a fairly good account of the subject matters treated. Measurement Techniques and Metrology (Nrs 1-33); Exposure to Natural Radiation in Non-Domestic Environments (34-56); Natural Radionuclides and Transfer Pathways (57-107); Radioactivity and Radiation in the Human Environment (108-183); Health Effects of Natural Radiation (184-205); Industrially Modified Levels of Radiation Exposure (206-219). (Quittner)

  8. LEO P: AN UNQUENCHED VERY LOW-MASS GALAXY

    Energy Technology Data Exchange (ETDEWEB)

    McQuinn, Kristen B. W.; Skillman, Evan D.; Berg, Danielle [Minnesota Institute for Astrophysics, School of Physics and Astronomy, 116 Church Street, S.E., University of Minnesota, Minneapolis, MN 55455 (United States); Dolphin, Andrew [Raytheon Company, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Cannon, John M. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Salzer, John J.; Rhode, Katherine L. [Department of Astronomy, Indiana University, 727 East 3rd Street, Bloomington, IN 47405 (United States); Adams, Elizabeth A. K. [ASTRON, the Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA, Dwingeloo (Netherlands); Giovanelli, Riccardo; Haynes, Martha P. [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Girardi, Léo, E-mail: kmcquinn@astro.umn.edu [Osservatorio Astronomico di Padova, INAF, Vicolo dell’Osservatorio 5, I-35122 Padova (Italy)

    2015-10-20

    Leo P is a low-luminosity dwarf galaxy discovered through the blind H i Arecibo Legacy Fast ALFA survey. The H i and follow-up optical observations have shown that Leo P is a gas-rich dwarf galaxy with active star formation, an underlying older population, and an extremely low oxygen abundance. We have obtained optical imaging with the Hubble Space Telescope to two magnitudes below the red clump in order to study the evolution of Leo P. We refine the distance measurement to Leo P to be 1.62 ± 0.15 Mpc, based on the luminosity of the horizontal branch stars and 10 newly identified RR Lyrae candidates. This places the galaxy at the edge of the Local Group, ∼0.4 Mpc from Sextans B, the nearest galaxy in the NGC 3109 association of dwarf galaxies of which Leo P is clearly a member. The star responsible for ionizing the H ii region is most likely an O7V or O8V spectral type, with a stellar mass ≳25 M{sub ⊙}. The presence of this star provides observational evidence that massive stars at the upper end of the initial mass function are capable of being formed at star formation rates as low as ∼10{sup −5} M{sub ⊙} yr{sup −1}. The best-fitting star formation history (SFH) derived from the resolved stellar populations of Leo P using the latest PARSEC models shows a relatively constant star formation rate over the lifetime of the galaxy. The modeled luminosity characteristics of Leo P at early times are consistent with low-luminosity dSph Milky Way satellites, suggesting that Leo P is what a low-mass dSph would look like if it evolved in isolation and retained its gas. Despite the very low mass of Leo P, the imprint of reionization on its SFH is subtle at best, and consistent with being totally negligible. The isolation of Leo P, and the total quenching of star formation of Milky Way satellites of similar mass, implies that the local environment dominates the quenching of the Milky Way satellites.

  9. Inclusion of Radiation Environment Variability in Total Dose Hardness Assurance Methodology

    Science.gov (United States)

    Xapsos, M. A.; Stauffer, C.; Phan, A.; McClure, S. S.; Ladbury, R. L.; Pellish, J. A.; Campola, M. J.; LaBel, K. A.

    2016-01-01

    Variability of the space radiation environment is investigated with regard to parts categorization for total dose hardness assurance methods. It is shown that it can have a significant impact. A modified approach is developed that uses current environment models more consistently and replaces the radiation design margin concept with one of failure probability during a mission.

  10. ABOUT INFLUENCE OF DIFFERENT SCHEMES IMPACT RADIATION ENVIRONMENTS AND LOADS ON REINFORCED LAMELLAR STRUCTURAL MEMBERS

    Directory of Open Access Journals (Sweden)

    Rafail B. Garibov

    2017-12-01

    Full Text Available The article discusses the model of deformation of fiber-reinforced concrete rectangular plate under the influence of radiation environments. In the calculation of the plate was considered different schemes impact of the applied external loads and radiation environments.

  11. Proceedings of the Scientific Meeting on Application of Isotopes and Radiation: Book 2. Chemistry, Environment, Radiation Process, And Industry

    International Nuclear Information System (INIS)

    Suhadi, F.; Sisworo, E.L.; Maha, M.; Ismachin, M.; Hilmy, N.; Sumatra, M.; Mugiono; Wandowo; Soebianto, Y.S.

    1998-01-01

    The aim of the 10th Meeting of the Isotope and Radiation Application is to disseminate the result of research on application of nuclear techniques on agriculture, animal, biology, chemistry, environment, radiation process and industry. The meeting was held in Jakarta, 18-19 February 1998, and there were 6 invited papers and 52 papers indexed individually. This proceeding is divided by two volumes. Volume I and volume II consists of agriculture, animal, biology and chemistry, environment, radiation process and industry, respectively.(ID)

  12. Radiation and its Role for Health, Environment and Industrial Development

    International Nuclear Information System (INIS)

    2010-01-01

    The presentation covers the applications of radioactive and nuclear materials in industry, medicine and biology, nuclear power and research. Applications of radiation in industry include non invasive measurement of density, thickness, moisture and levels of liquids and solid materials. Also covered are the applications of radiation in waste water treatment and its use in medicine for diagnosis, therapy, tracer studies and sterilization of medical dressings.In industry radiation is used in non destructive testing of metal and steel structures.

  13. Radiation in controlled environments: influence of lamp type and filter material

    Science.gov (United States)

    Bubenheim, D. L.; Bugbee, B.; Salisbury, F. B.

    1988-01-01

    Radiation in controlled environments was characterized using fluorescent and various high-intensity-discharge (HID) lamps, including metal halide, low-pressure sodium, and high-pressure sodium as the radiation source. The effects of water, glass, or Plexiglas filters on radiation were determined. Photosynthetic photon flux (PPF, 400 to 700 nm), spectra (400 to 1000 nm), shortwave radiation (285-2800 nm), and total radiation (300 to 100,000 nm) were measured, and photosynthetically active radiation (PAR, 400 to 700 nm) and longwave radiation (2800 to 100,000 nm) were calculated. Measurement of PPF alone was not an adequate characterization of the radiation environment. Total radiant flux varied among lamp types at equal PPF. HID lamps provided a lower percentage of longwave radiation than fluorescent lamps, but, when HID lamps provided PPF levels greater than that possible with fluorescent lamps, the amount of longwave radiation was high. Water was the most effective longwave radiation filter. Glass and Plexiglas similarly filtered longwave more than shortwave radiation, but transmission of nonphotosynthetic shortwave radiation was less with Plexiglas than glass. The filter materials tested would not be expected to influence photomorphogenesis because radiation in the action spectrum of phytochrome was not altered, but this may not be the only pigment involved.

  14. NASA Strategy to Safely Live and Work in the Space Radiation Environment

    Science.gov (United States)

    Cucinotta, Francis; Wu, Honglu; Corbin, Barbara; Sulzman, Frank; Kreneck, Sam

    2007-01-01

    This viewgraph document reviews the radiation environment that is a significant potential hazard to NASA's goals for space exploration, of living and working in space. NASA has initiated a Peer reviewed research program that is charged with arriving at an understanding of the space radiation problem. To this end NASA Space Radiation Laboratory (NSRL) was constructed to simulate the harsh cosmic and solar radiation found in space. Another piece of the work was to develop a risk modeling tool that integrates the results from research efforts into models of human risk to reduce uncertainties in predicting risk of carcinogenesis, central nervous system damage, degenerative tissue disease, and acute radiation effects acute radiation effects.

  15. Radiation, waves, fields. Causes and effects on environment and health

    International Nuclear Information System (INIS)

    Leitgeb, N.

    1990-01-01

    The book discusses static electricity, alternating electric fields, magnetostatic fields, alternating magnetic fields, electromagnetic radiation, optical and ionizing radiation and their hazards and health effects. Each chapter presents basic physical and biological concepts and describes the common radiation sources and their biological effects. Each chapter also contains hints for everyday behaviour as well as in-depth information an specific scientific approaches for assessing biological effects; the latter are addressed to all expert readers working in these fields. There is a special chapter on the problem of so-called 'terrestrial radiation'. (orig.) With 88 figs., 31 tabs [de

  16. Wave Optics Based LEO-LEO Radio Occultation Retrieval

    DEFF Research Database (Denmark)

    von Benzon, Hans-Henrik; Høeg, Per

    2016-01-01

    optics based retrieval chain is used on a number of examples and the retrieved atmospheric parameters are compared to the parameters from a global ECMWF analysis model. This model is used in a forward propagator that simulates the electromagnetic field amplitudes and phases at the receiver on board...... receiver on board a Low Earth Orbit (LEO) satellite. The technique is based on the Doppler shift imposed, by the atmosphere, on the signal emitted from the GPS satellite. Two LEO satellites are assumed in the occultations discussed in this paper and the retrieval is also dependent on the decrease...

  17. Mitochondrial genome of the African lion Panthera leo leo.

    Science.gov (United States)

    Ma, Yue-ping; Wang, Shuo

    2015-01-01

    In this study, the complete mitochondrial genome sequence of the African lion P. leo leo was reported. The total length of the mitogenome was 17,054 bp. It contained the typical mitochondrial structure, including 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 1 control region; 21 of the tRNA genes folded into typical cloverleaf secondary structure except for tRNASe. The overall composition of the mitogenome was A (32.0%), G (14.5%), C (26.5%) and T (27.0%). The new sequence will provide molecular genetic information for conservation genetics study of this important large carnivore.

  18. RADIATION ENVIRONMENT AT AVIATION ALTITUDES AND IN SPACE

    Czech Academy of Sciences Publication Activity Database

    Sihver, L.; Ploc, Ondřej; Puchalska, M.; Ambrožová, Iva; Kubančák, Ján; Kyselová, Dagmar; Shurshakov, V.

    2015-01-01

    Roč. 164, č. 4 (2015), s. 477-483 ISSN 0144-8420 Institutional support: RVO:61389005 Keywords : cosmic radiation * radiation field * on-board spacecraft Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.894, year: 2015

  19. Development of clean environment conservation technology by radiation

    International Nuclear Information System (INIS)

    Lee, Myunjoo; Kim, Tak Hyun; Jung, In Ha

    2012-04-01

    This report is aim to develop the technology for environmental conservation by radiation. It is consisted of two research parts. One is development of wastewater disinfection technology by radiation and the other is development of livestock waste treatment technology by radiation. For the development of wastewater disinfection technology disinfect ion process, technology for treatment of toxic organic chemicals and assessment of ecological toxicity, technology for treatment of endocrine disrupting chemicals and assessment of genetic safety were developed. For the development of livestock waste treatment technology, process for simultaneous removal of nutrients, technology for disinfection and quality enhancement of livestock waste compost, technology for reduction of composting periods, monitoring of toxic organic compounds, pretreatment technology for organic toxic chemicals and enhancement of biological treatment efficiencies were developed. Based on basic research, advanced livestock wastewater treatment process using radiation was established

  20. Activation and radiation damage in the environment of hadron accelerators

    CERN Document Server

    Kiselev, Daniela

    2013-01-01

    A component which suffers radiation damage usually also becomes radioactive, since the source of activation and radiation damage is the interaction of the material with particles from an accelerator or with reaction products. However, the underlying mechanisms of the two phenomena are different. These mechanisms are described here. Activation and radiation damage can have far-reaching consequences. Components such as targets, collimators, and beam dumps are the first candidates for failure as a result of radiation damage. This means that they have to be replaced or repaired. This takes time, during which personnel accumulate dose. If the dose to personnel at work would exceed permitted limits, remote handling becomes necessary. The remaining material has to be disposed of as radioactive waste, for which an elaborate procedure acceptable to the authorities is required. One of the requirements of the authorities is a complete nuclide inventory. The methods used for calculation of such inventories are presented,...

  1. Environment and health: 3. Ozone depletion and ultraviolet radiation

    International Nuclear Information System (INIS)

    De Gruijl, F.R.; Van der Leun, J.C.

    2000-01-01

    Ultraviolet radiation from the sun is responsible for a variety of familiar photochemical reactions, including photochemical smog, bleaching of paints and decay of plastics. Conjugated bonds in organic molecules such as proteins and DNA absorb the UV radiation, which can damage these molecules. By a fortunate evolutionary event, the oxygen produced by photosynthesis forms a filter in the outer reaches of our atmosphere that absorbs the most energetic and harmful UV radiation, with wavelengths below 240 nm (in the UVC band [wavelength 100-280 nm]). In the process, the oxygen molecules split up and recombine to form ozone (Fig. 1). This ratified ozone layer (spread out between 10 and 50 Ion in the stratosphere but only 3 mm thick were it compressed at ground level) in turn efficiently absorbs UV radiation of higher wavelengths (tip to about 310 nm). A part of the UV radiation in the UVB band (wavelength 280-315 nm) still reaches ground level and is absorbed in sufficient amounts to have deleterious effects on cells. The less energetic radiation in the UVA band (wavelength 315-400 nm, bordering the visible band [wavelength 400-800 nm]) is not absorbed by ozone and reaches ground level without much attenuation through a clear atmosphere (i.e., no clouds, no air pollution). Although not completely innocuous, the UVA radiation in sunlight is much less photochemically active and therefore generally less harmful than UVB radiation. Life on earth has adapted itself to the UV stress, particularly UVB stress, fbr example by forming protective UV-absorbing surface layers, by repairing cell damage or by replacing damaged cells entirely. Human skin shows all of these adaptive features. Our eyes are less well adapted, but dicy, are shielded by the brows and by squinting. (author)

  2. Experimental checking results of mathematical modeling of the radiation environment sensor based on diamond detectors

    International Nuclear Information System (INIS)

    Gladchenkov, E V; Kolyubin, V A; Nedosekin, P G; Zaharchenko, K V; Ibragimov, R F; Kadilin, V V; Tyurin, E M

    2017-01-01

    Were conducted a series of experiments, the purpose of which had to verify the mathematical model of the radiation environment sensor. Theoretical values of the beta particles count rate from 90 Sr - 90 Y source registered by radiation environment sensor was compared with the experimental one. Theoretical (calculated) count rate of beta particles was found with using the developed mathematical model of the radiation environment sensor. Deviation of the calculated values of the beta particle count rate does not exceed 10% from the experimental. (paper)

  3. Leo Tolstoy the Spiritual Educator

    Science.gov (United States)

    Moulin, Dan

    2008-01-01

    This paper considers the often overlooked religious and educational works of the Russian novelist Leo Tolstoy (1828-1910). After outlining Tolstoy's life, religious and educational views, it is argued that Tolstoy has much to offer spiritual educators today. In particular, it suggests Tolstoy's insistence on the absolute and eternal nature of…

  4. Comparative proteomic analysis of rice after seed ground simulated radiation and spaceflight explains the radiation effects of space environment

    Science.gov (United States)

    Wang, Wei; Shi, Jinming; Liang, Shujian; Lei, Huang; Shenyi, Zhang; Sun, Yeqing

    In previous work, we compared the proteomic profiles of rice plants growing after seed space-flights with ground controls by two-dimensional difference gel electrophoresis (2-D DIGE) and found that the protein expression profiles were changed after seed space environment exposures. Spaceflight represents a complex environmental condition in which several interacting factors such as cosmic radiation, microgravity and space magnetic fields are involved. Rice seed is in the process of dormant of plant development, showing high resistance against stresses, so the highly ionizing radiation (HZE) in space is considered as main factor causing biological effects to seeds. To further investigate the radiation effects of space environment, we performed on-ground simulated HZE particle radiation and compared between the proteomes of seed irra-diated plants and seed spaceflight (20th recoverable satellite) plants from the same rice variety. Space ionization shows low-dose but high energy particle effects, for searching the particle effects, ground radiations with the same low-dose (2mGy) but different liner energy transfer (LET) values (13.3KeV/µm-C, 30KeV/µm-C, 31KeV/µm-Ne, 62.2KeV/µm-C, 500Kev/µm-Fe) were performed; using 2-D DIGE coupled with clustering and principle component analysis (PCA) for data process and comparison, we found that the holistic protein expression patterns of plants irradiated by LET-62.2KeV/µm carbon particles were most similar to spaceflight. In addition, although space environment presents a low-dose radiation (0.177 mGy/day on the satellite), the equivalent simulated radiation dose effects should still be evaluated: radiations of LET-62.2KeV/µm carbon particles with different cumulative doses (2mGy, 20mGy, 200mGy, 2000mGy) were further carried out and resulted that the 2mGy radiation still shared most similar proteomic profiles with spaceflight, confirming the low-dose effects of space radiation. Therefore, in the protein expression level

  5. Some technologically enhanced exposures to natural radiation environment in India

    International Nuclear Information System (INIS)

    Lalit, B.Y.; Shukla, V.K.; Ramachandran, T.V.; Mishra, U.C.

    1982-01-01

    A summary of results of gamma spectrometric measurements of natural radioactivity in a number of coal and flyash samples from thermal power plants and phosphatic fertilizer samples collected from various fertilizer plants in India are presented. These constitute the sources of technologically enhanced exposures to natural radiation. A brief description of sampling and measurement procedures is given. The radiation doses to the population from coal burning for electricity generation have been calculated using the method outlined in UNSCEAR report of 1979 with corrections for local population density. The external radiation dose to the farmers has been calculated on the basis of usage of phosphatic fertilizers for rice, wheat, millets and sugarcane crops for the normal agricultural practices

  6. Measurement of gamma radiation doses in nuclear power plant environment

    International Nuclear Information System (INIS)

    Bochvar, I.A.; Keirim-Markus, I.B.; Sergeeva, N.A.

    1976-01-01

    Considered are the problems of measuring gamma radiation dose values and the dose distribution in the nuclear power plant area with the aim of estimating the extent of their effect on the population. Presented are the dosimeters applied, their distribution throughout the controlled area, time of measurement. The distribution of gamma radiation doses over the controlled area and the dose alteration with the increase of the distance from the release source are shown. The results of measurements are investigated. The conclusion is made that operating nuclear power plants do not cause any increase in the gamma radiation dose over the area. Recommendations for clarifying the techniques for using dose-meters and decreasing measurement errors are given [ru

  7. Uranium mining and processing: their radiation impact into the environment

    International Nuclear Information System (INIS)

    Ostapczuk, Peter; Zoriy, Petro; Dederichs, Herbert; Lennartz, Reinhard

    2008-01-01

    Based on Thorium and Uranium determination in soil and plants samples collected in the region of Aktau, Kazakhstan the distribution pattern of environmental pollution by these elements was correlated with the radiation dose. The main radiation source was the waste deposit of the equipment used by the uranium processing (dose higher than 5 μSv/h). The mining area and also the transportation way from mine to the uranium factory has also an radiation impact which is difficult to estimate. Based on the data found by plants and soil samples all the area under study has a higher pollution level by Thorium and Uranium than the control area (about 0.1μSv/h). Due to observed strong wind blowing in different directions it is possible that the particle of uranium ore has been transported for long distance and polluted the plants and upper soil layer. The further investigations should get more information about this supposition. (author)

  8. Applications of isotopes and radiation in conservation of the environment

    International Nuclear Information System (INIS)

    1992-01-01

    The objective of the symposium was to review present knowledge of the applications of radiation, radioisotopes and nuclear methods of analysis in the monitoring and control of environmental pollution and in reducing emissions of environmentally toxic substances. The scientific programme covered a wide range of different applications of nuclear technology, such as flue gas purification, radiation processing of liquid and solid wastes, radiotracer studies and nuclear analytical techniques and their applications. The symposium was attended by 92 participants representing 31 IAEA Member States. Separate abstracts were prepared for 46 of the papers in this volume. Refs, figs and tabs

  9. LHCb: Evaluation of the Radiation Environment of the LHCb Experiment

    CERN Multimedia

    Karacson, M

    2011-01-01

    The characterization of all aspects of the radiation field of the LHCb experiment is needed to understand the impact of the unprecedented radiation levels to which its detector and electronics are exposed to. The methodology on how this is done is described. Analysis of the measurements of active and passive sensors of various types which are distributed in and around the detector will be carried out. Appropriate cross calibrations will be applied and comparisons between them will be performed. Critical comparisons with simulation results obtained with the FLUKA Monte Carlo code are also an essential element of the study.

  10. The Ionizing Radiation Environment on the International Space Station: Performance vs. Expectations for Avionics and Materials

    Science.gov (United States)

    Koontz, Steven L.; Boeder, Paul A.; Pankop, Courtney; Reddell, Brandon

    2005-01-01

    The role of structural shielding mass in the design, verification, and in-flight performance of International Space Station (ISS), in both the natural and induced orbital ionizing radiation (IR) environments, is reported.

  11. Proceedings. Protection of the natural environment. International symposium on ionising radiation

    International Nuclear Information System (INIS)

    Amiro, B.; Johansson, Gunnar; Larsson, Carl-Magnus; Luening, M.

    1996-01-01

    The symposium was organised jointly by the Swedish Radiation Protection Institute and the Atomic Energy Control Board of Canada. The programme was organised around six major topics: Biological effects of ionising radiation; Ecological effects of ionising radiation; Behaviour and transport of radionuclides in the natural environment; Criteria for environmental protection; Assessment methodology; and Social and economic aspects. All 86 contributions (excluding the opening addresses) have been separately indexed

  12. Mars' surface radiation environment measured with the Mars science laboratory's curiosity rover

    NARCIS (Netherlands)

    Hassler, D.M.; Zeitlin, C.; Wimmer-Schweingruber, R.F.; Ehresmann, B.; Rafkin, S.; Eigenbrode, J.L.; Brinza, D.E.; Weigle, G.; Böttcher, S.; Böhm, E.; Burmeister, S.; Guo, J.; Köhler, J.; Martin, C.; Reitz, G.; Cucinotta, F.A.; Kim, M.-H.; Grinspoon, D.; Bullock, M.A.; Posner, A.; Gómez-Elvira, J.; Vasavada, A.; Grotzinger, J.P.; MSL Science Team, the|info:eu-repo/dai/nl/292012217

    2014-01-01

    The Radiation Assessment Detector (RAD) on the Mars Science Laboratory’s Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose

  13. Radiation tolerant passive and active optical fiber products for use in space environments

    Science.gov (United States)

    Hill, Mark; Hankey, Judith; Gray, Rebecca

    2017-11-01

    This paper reports the radiation performance results of several new product types designed for high radiation environments. The products tested include radiation hardened highly birefringent (HiBi) passive products for polarised applications and radiation tolerant active erbium doped fiber products for amplifiers. Radiation hardened, short beatlength HiBi fiber products have been developed for high accuracy polarisation maintaining (PM) gyros and sensors at both 1310nm and 1550nm operation in the space environment. The fibers have been tested up to 5kGy (500krad) - levels which could be expected in extreme, extra-terrestrial space environments. Results show a consistently low Radiation Induced Attenuation (RIA) of fibers are intended for use in multichannel amplifiers in optical intersatellite communications. The structure of the fibers have been designed to deliver an accelerated recovery of radiation damage through photo-annealing using only the residual energy already available in an amplifier using a 980nm pumping regime. These products have been tested up to 200Gy (20krad) - levels which can be expected in Earth orbit environments over a 20-30 mission lifetime. Results show up to 100% recovery under continuous use for dose rates of 0.11rad/hr. It has also been demonstrated through analysis of the optical spectral output that this effect reverses the gain tilt, or spectral narrowing, induced by radiation damage through the C and L band. These combined fiber characteristics allow performance stability of the amplifier over the lifetime of the space mission.

  14. Isotopes and radiations in agriculture and environment research

    International Nuclear Information System (INIS)

    Sachdev, M.S.; Sachdev, P.; Deb, D.L.

    1996-10-01

    The use of isotope and radiation techniques in agriculture and environmental research has considerably helped in meeting the challenges of increasing crop and animal production. The present compilation presents the state of the art on the use of these techniques particularly in the context of current research and development programmes in this field. Papers relevant to INIS are indexed separately

  15. Using a Commercial Ethernet PHY Device in a Radiation Environment

    Science.gov (United States)

    Parks, Jeremy; Arani, Michael; Arroyo, Roberto

    2014-01-01

    This work involved placing a commercial Ethernet PHY on its own power boundary, with limited current supply, and providing detection methods to determine when the device is not operating and when it needs either a reset or power-cycle. The device must be radiation-tested and free of destructive latchup errors. The commercial Ethernet PHY's own power boundary must be supplied by a current-limited power regulator that must have an enable (for power cycling), and its maximum power output must not exceed the PHY's input requirements, thus preventing damage to the device. A regulator with configurable output limits and short-circuit protection (such as the RHFL4913, rad hard positive voltage regulator family) is ideal. This will prevent a catastrophic failure due to radiation (such as a short between the commercial device's power and ground) from taking down the board's main power. Logic provided on the board will detect errors in the PHY. An FPGA (field-programmable gate array) with embedded Ethernet MAC (Media Access Control) will work well. The error detection includes monitoring the PHY's interrupt line, and the status of the Ethernet's switched power. When the PHY is determined to be non-functional, the logic device resets the PHY, which will often clear radiation induced errors. If this doesn't work, the logic device power-cycles the FPGA by toggling the regulator's enable input. This should clear almost all radiation induced errors provided the device is not latched up.

  16. Diamond and silicon pixel detectors in high radiation environments

    Energy Technology Data Exchange (ETDEWEB)

    Tsung, Jieh-Wen

    2012-10-15

    Diamond pixel detector is a promising candidate for tracking of collider experiments because of the good radiation tolerance of diamond. The diamond pixel detector must withstand the radiation damage from 10{sup 16} particles per cm{sup 2}, which is the expected total fluence in High Luminosity Large Hadron Collider. The performance of diamond and silicon pixel detectors are evaluated in this research in terms of the signal-to-noise ratio (SNR). Single-crystal diamond pixel detectors with the most recent readout chip ATLAS FE-I4 are produced and characterized. Based on the results of the measurement, the SNR of diamond pixel detector is evaluated as a function of radiation fluence, and compared to that of planar-silicon ones. The deterioration of signal due to radiation damage is formulated using the mean free path of charge carriers in the sensor. The noise from the pixel readout circuit is simulated and calculated with leakage current and input capacitance to the amplifier as important parameters. The measured SNR shows good agreement with the calculated and simulated results, proving that the performance of diamond pixel detectors can exceed the silicon ones if the particle fluence is more than 10{sup 15} particles per cm{sup 2}.

  17. Time-dependent effects on CMOS total-dose response in accelerator radiation environments

    International Nuclear Information System (INIS)

    Fleetwood, D.; Winokur, P.; Shaw, D.; Barnes, C.

    1994-01-01

    Time-dependent charge buildup and annealing processes cause the ionizing radiation response of CMOS devices and circuits in an accelerator radiation environment to depend strongly on the dose rate of the exposure. Oxide-trap charge annealing and interface-trap buildup in nMOS transistors can lead to positive threshold voltage shifts in a low-dose-rate radiation environment, while negative threshold-voltage shifts are commonly observed after irradiations at typical laboratory dose rates [50-300 rad(Si)/s]. Thus, devices that pass laboratory testing can fail at the low dose rates encountered in a high-energy particle-accelerator radiation environment due to positive nMOS transistor threshold-voltage shifts above preirradiation values, i.e., open-quotes rebound.close quotes The authors discuss how this issue can be addressed in total-dose hardness assurance test methods for accelerator environments. An example is the revised US military-standard ionizing-radiation-effects test method (MIL-STD 883D, Test Method 1019.4). Finally, it is noted that the 1/f noise of radiation-hardened MOS electronics should be significantly lower than that of commercial electronics both in and outside of a radiation environment

  18. The radiation performance standard. A presentation model for ionizing radiation in the living environment

    International Nuclear Information System (INIS)

    Schaap, L.E.J.J.; Bosmans, G.; Van der Graaf, E.R.; Hendriks, Ch.F.

    1998-01-01

    By means of the so-called radiation performance standard (SPN, abbreviated in Dutch) the total radioactivity from building constructions which contributes to the indoor radiation dose can be calculated. The SPN is implemented with related boundary values and is part of the Building Decree ('Bouwbesluit') in the Netherlands. The model, presented in this book, forms the basis of a new Dutch radiation protection standard, to be published by the Dutch Institute for Standardization NEN (formerly NNI). 14 refs

  19. VCHP Radiators for Lunar and Martian Environments, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Long-term Lunar and Martian systems present challenges to thermal control systems, including changes in thermal load, and large changes in the thermal environment...

  20. VCHP Radiators for Lunar and Martian Environments, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Long-term Lunar and Martian systems present challenges to thermal systems, including changes in thermal load, and large changes in the thermal environment between...

  1. A study of Latchup phenomenon induced in integrated circuits subject to an radiation field environment

    International Nuclear Information System (INIS)

    Merabtine, Nadjim; Sadaoui, Djaouida; Benslama, Malek

    2007-01-01

    [Text of English abstract is entered here]. The electronic equipment operated in hostile environment can undergo beside failures due to the normal component aging, degradation due to the environmental conditions of functioning. The interaction of the particles composing a radiation environment with materials within an integrated circuit can induce failures perturbing its functioning or eventually its destruction. The study of the radiation effects on integrated circuits particularly of the Latchup effect aims at evaluating the reliability of electronic systems subject to radiation. The objective of this work will be focused especially upon the Latchup phenomenon induced in the implied components. (authors) [fr

  2. MARS15 Simulation of Radiation Environment at the ESS Linac

    Energy Technology Data Exchange (ETDEWEB)

    Mokhov, N. V. [Fermilab; Eidelman, Yu. I. [Euclid Techlabs, Solon; Rakhno, I. L. [Fermilab; Tchelidze, L. [ESS, Lund; Tropin, I. S. [Fermilab

    2016-12-01

    Comprehensive studies with the MARS15(2016) Monte-Carlo code are described on evaluation of prompt and residual radiation levels induced by nominal and accidental beam losses in the 5-MW, 2-GeV European Spallation Source (ESS) Linac. These are to provide a basis for radiation shielding design verification through the accelerator complex. The calculation model is based on the latest engineering design and includes a sophisticated algorithm for particle tracking in the machine RF cavities as well as a well-established model of the beam loss. Substantial efforts were put in solving the deep-penetration problem for the thick shielding around the tunnel with numerous complex penetrations. It allowed us to study in detail not only the prompt dose, but also component and air activation, radiation loads on the soil outside the tunnel, and skyshine studies for the complicated 3-D surface above the machine. Among the other things, the newest features in MARS15 (2016), such as a ROOT-based beamline builder and a TENDL-based event generator for nuclear interactions below 100 MeV, were very useful in this challenging application

  3. Radiation damage response of ceramics in extreme environments

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-10-15

    Oxide-based and inter-metallic compounds have great potential as new materials for clean and renewable energy production. Many of these materials, especially those designed for operation in Generation IV fission reactors or in fusion reactors, must exhibit robust performance under extreme conditions of temperature, irradiation, and chemical attack. Others, such as nuclear waste forms, may be required to retain radioactive elements for long periods of time in geological repositories. The mechanisms of radiation damage production and recovery in these materials may vary considerably as a function of the damage source, e.g., energetic neutrons in reactor systems versus alpha decay in nuclear waste forms. Furthermore, the kinetics of damage recovery are complicated by multiply activated processes and in certain cases, longer-term diffusion may modify the structural state left by irradiation in the short term. Here, we review some basic concepts regarding the mechanisms of radiation damage in selected ceramic materials, including mathematical models, fluence-temperature relationships, and predictive methodologies. A major consideration for materials performance is the ability of a given compound to resist amorphization. Historically, there are a number of general criteria for radiation resistance, including those involving melting point (thermodynamics), structural freedom, bonding, and energetics of defect formation. These are discussed using specific examples. (Author)

  4. Simulation of the synergistic low Earth orbit effects of vacuum thermal cycling, vacuum UV radiation, and atomic oxygen

    Science.gov (United States)

    Dever, Joyce A.; Degroh, Kim K.; Stidham, Curtis R.; Stueber, Thomas J.; Dever, Therese M.; Rodriguez, Elvin; Terlep, Judith A.

    1992-01-01

    In order to assess the low Earth orbit (LEO) durability of candidate space materials, it is necessary to use ground laboratory facilities which provide LEO environmental effects. A facility combining vacuum thermal cycling and vacuum ultraviolet (VUV) radiation has been designed and constructed at NASA Lewis Research Center for this purpose. This facility can also be operated without the VUV lamps. An additional facility can be used to provide VUV exposure only. By utilizing these facilities, followed by atomic oxygen exposure in an RF plasma asher, the effects of the individual vacuum thermal cycling and VUV environments can be compared to the effect of the combined vacuum thermal cycling/VUV environment on the atomic oxygen durability of materials. The synergistic effects of simulated LEO environmental conditions on materials were evaluated by first exposing materials to vacuum thermal cycling, VUV, and vacuum thermal cycling/VUV environments followed by exposure to atomic oxygen in an RP plasma asher. Candidate space power materials such as atomic oxygen protected polyimides and solar concentrator mirrors were evaluated using these facilities. Characteristics of the Vacuum Thermal Cycling/VUV Exposure Facility which simulates the temperature sequences and solar ultraviolet radiation exposure that would be experienced by a spacecraft surface in LEO are discussed. Results of durability evaluations of some candidate space power materials to the simulated LEO environmental conditions will also be discussed. Such results have indicated that for some materials, atomic oxygen durability is affected by previous exposure to thermal cycling and/or VUV exposure.

  5. Application to the conservation of RF tags in the radiation environment

    International Nuclear Information System (INIS)

    Teraura, Nobuyuki; Ito, Kunio; Takahashi, Naoki; Sakurai, Kouichi

    2011-01-01

    RF tags that are implemented RFID technology as tag has been used in various fields. Tags have been developed, such as resistance to chemicals and high temperature resistant RF tags are also used in specialized fields. The RF tag apply to the existing nuclear field, had been concerned about the effects of radiation to the RF tags. Now, since the RF tag with a goal to develop radiation-proof, we have examined, such as applying for maintenance of nuclear facilities under radiation environment. We report the results and RF tags to be radiation resistant. (author)

  6. Collection of radiation resistant characteristics reports for instruments and materials in high dose rate environment

    International Nuclear Information System (INIS)

    Kusano, Joichi

    2008-03-01

    This document presents the collected official reports of radiation irradiation study for the candidate materials to be used in high dose rate environment as J-PARC facility. The effect of radiation damage by loss-beam or secondary particle beam of the accelerators influences the performance and the reliability of various instruments. The knowledge on the radiation resistivity of the materials is important to estimate the life of the equipments, the maintenance interval and dose evaluation for the personnel at the maintenance period. The radiation damage consists with mechanical property, electrical property and gas-evolution property. (author)

  7. Monte Carlo simulations of the radiation environment for the CMS Experiment

    CERN Document Server

    AUTHOR|(CDS)2068566; Bayshev, I.; Bergstrom, I.; Cooijmans, T.; Dabrowski, A.; Glöggler, L.; Guthoff, M.; Kurochkin, I.; Vincke, H.; Tajeda, S.

    2016-01-01

    Monte Carlo radiation transport codes are used by the CMS Beam Radiation Instrumentation and Luminosity (BRIL) project to estimate the radiation levels due to proton-proton collisions and machine induced background. Results are used by the CMS collaboration for various applications: comparison with detector hit rates, pile-up studies, predictions of radiation damage based on various models (Dose, NIEL, DPA), shielding design, estimations of residual dose environment. Simulation parameters, and the maintenance of the input files are summarised, and key results are presented. Furthermore, an overview of additional programs developed by the BRIL project to meet the specific needs of CMS community is given.

  8. Performances of Kevlar and Polyethylene as radiation shielding on-board the International Space Station in high latitude radiation environment.

    Science.gov (United States)

    Narici, Livio; Casolino, Marco; Di Fino, Luca; Larosa, Marianna; Picozza, Piergiorgio; Rizzo, Alessandro; Zaconte, Veronica

    2017-05-10

    Passive radiation shielding is a mandatory element in the design of an integrated solution to mitigate the effects of radiation during long deep space voyages for human exploration. Understanding and exploiting the characteristics of materials suitable for radiation shielding in space flights is, therefore, of primary importance. We present here the results of the first space-test on Kevlar and Polyethylene radiation shielding capabilities including direct measurements of the background baseline (no shield). Measurements are performed on-board of the International Space Station (Columbus modulus) during the ALTEA-shield ESA sponsored program. For the first time the shielding capability of such materials has been tested in a radiation environment similar to the deep-space one, thanks to the feature of the ALTEA system, which allows to select only high latitude orbital tracts of the International Space Station. Polyethylene is widely used for radiation shielding in space and therefore it is an excellent benchmark material to be used in comparative investigations. In this work we show that Kevlar has radiation shielding performances comparable to the Polyethylene ones, reaching a dose rate reduction of 32 ± 2% and a dose equivalent rate reduction of 55 ± 4% (for a shield of 10 g/cm 2 ).

  9. PABLM: a computer program to calculate accumulated radiation doses from radionuclides in the environment

    International Nuclear Information System (INIS)

    Napier, B.A.; Kennedy, W.E. Jr.; Soldat, J.K.

    1980-03-01

    A computer program, PABLM, was written to facilitate the calculation of internal radiation doses to man from radionuclides in food products and external radiation doses from radionuclides in the environment. This report contains details of mathematical models used and calculational procedures required to run the computer program. Radiation doses from radionuclides in the environment may be calculated from deposition on the soil or plants during an atmospheric or liquid release, or from exposure to residual radionuclides in the environment after the releases have ended. Radioactive decay is considered during the release of radionuclides, after they are deposited on the plants or ground, and during holdup of food after harvest. The radiation dose models consider several exposure pathways. Doses may be calculated for either a maximum-exposed individual or for a population group. The doses calculated are accumulated doses from continuous chronic exposure. A first-year committed dose is calculated as well as an integrated dose for a selected number of years. The equations for calculating internal radiation doses are derived from those given by the International Commission on Radiological Protection (ICRP) for body burdens and MPC's of each radionuclide. The radiation doses from external exposure to contaminated water and soil are calculated using the basic assumption that the contaminated medium is large enough to be considered an infinite volume or plane relative to the range of the emitted radiations. The equations for calculations of the radiation dose from external exposure to shoreline sediments include a correction for the finite width of the contaminated beach

  10. Bullying among radiation therapists: effects on job performance and work environment.

    Science.gov (United States)

    Trad, Megan; Johnson, Jordan

    2014-01-01

    To identify the effects of workplace bullying in the radiation therapy department on job performance and explore the environment and morale of individuals who work with a bully. A quantitative research study was designed to assess the prevalence and effects of bullying in the radiation therapy workplace. A total of 308 radiation therapists participated in the study for a return rate of 46%. Of those, 194 indicated that workplace bullying was present either in their current workplace or in a previous radiation therapy environment and that it negatively affected job performance and satisfaction. Findings of this study indicate a need for evaluation of the radiation therapy workplace, education on how to identify and prevent bullying behavior, and better communication among members of the radiation therapy environment. Participants indicated that working in a hostile environment led to forgetfulness, ineffective communication, and perceived discrepancies in promotion and treatment by management. Any bullying behavior contributes to an overall toxic work environment, which is unhealthy and unsafe for patients and therapists. Those who manage therapists should promote a culture of safety and embrace their staff's independence.

  11. Mars' surface radiation environment measured with the Mars Science Laboratory's Curiosity rover.

    Science.gov (United States)

    Hassler, Donald M; Zeitlin, Cary; Wimmer-Schweingruber, Robert F; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L; Brinza, David E; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P

    2014-01-24

    The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.

  12. Mars' Surface Radiation Environment Measured with the Mars Science Laboratory's Curiosity Rover

    Science.gov (United States)

    Hassler, Donald M.; Zeitlin, Cary; Wimmer-Schweingruber, Robert F.; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L.; Brinza, David E.; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A.; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A.; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P.; MSL Science Team; Kemppinen, Osku; Cremers, David; Bell, James F.; Edgar, Lauren; Farmer, Jack; Godber, Austin; Wadhwa, Meenakshi; Wellington, Danika; McEwan, Ian; Newman, Claire; Richardson, Mark; Charpentier, Antoine; Peret, Laurent; King, Penelope; Blank, Jennifer; Schmidt, Mariek; Li, Shuai; Milliken, Ralph; Robertson, Kevin; Sun, Vivian; Baker, Michael; Edwards, Christopher; Ehlmann, Bethany; Farley, Kenneth; Griffes, Jennifer; Miller, Hayden; Newcombe, Megan; Pilorget, Cedric; Rice, Melissa; Siebach, Kirsten; Stack, Katie; Stolper, Edward; Brunet, Claude; Hipkin, Victoria; Léveillé, Richard; Marchand, Geneviève; Sánchez, Pablo Sobrón; Favot, Laurent; Cody, George; Steele, Andrew; Flückiger, Lorenzo; Lees, David; Nefian, Ara; Martin, Mildred; Gailhanou, Marc; Westall, Frances; Israël, Guy; Agard, Christophe; Baroukh, Julien; Donny, Christophe; Gaboriaud, Alain; Guillemot, Philippe; Lafaille, Vivian; Lorigny, Eric; Paillet, Alexis; Pérez, René; Saccoccio, Muriel; Yana, Charles; Armiens-Aparicio, Carlos; Rodríguez, Javier Caride; Blázquez, Isaías Carrasco; Gómez, Felipe Gómez; Hettrich, Sebastian; Malvitte, Alain Lepinette; Jiménez, Mercedes Marín; Martínez-Frías, Jesús; Martín-Soler, Javier; Martín-Torres, F. Javier; Jurado, Antonio Molina; Mora-Sotomayor, Luis; Caro, Guillermo Muñoz; López, Sara Navarro; Peinado-González, Verónica; Pla-García, Jorge; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio José; Fuentes, Sara Alejandra Sans; Martinez, Eduardo Sebastian; Redondo, Josefina Torres; Urqui-O'Callaghan, Roser; Mier, María-Paz Zorzano; Chipera, Steve; Lacour, Jean-Luc; Mauchien, Patrick; Sirven, Jean-Baptiste; Manning, Heidi; Fairén, Alberto; Hayes, Alexander; Joseph, Jonathan; Squyres, Steven; Sullivan, Robert; Thomas, Peter; Dupont, Audrey; Lundberg, Angela; Melikechi, Noureddine; Mezzacappa, Alissa; Berger, Thomas; Matthia, Daniel; Prats, Benito; Atlaskin, Evgeny; Genzer, Maria; Harri, Ari-Matti; Haukka, Harri; Kahanpää, Henrik; Kauhanen, Janne; Kemppinen, Osku; Paton, Mark; Polkko, Jouni; Schmidt, Walter; Siili, Tero; Fabre, Cécile; Wray, James; Wilhelm, Mary Beth; Poitrasson, Franck; Patel, Kiran; Gorevan, Stephen; Indyk, Stephen; Paulsen, Gale; Gupta, Sanjeev; Bish, David; Schieber, Juergen; Gondet, Brigitte; Langevin, Yves; Geffroy, Claude; Baratoux, David; Berger, Gilles; Cros, Alain; d'Uston, Claude; Forni, Olivier; Gasnault, Olivier; Lasue, Jérémie; Lee, Qiu-Mei; Maurice, Sylvestre; Meslin, Pierre-Yves; Pallier, Etienne; Parot, Yann; Pinet, Patrick; Schröder, Susanne; Toplis, Mike; Lewin, Éric; Brunner, Will; Heydari, Ezat; Achilles, Cherie; Oehler, Dorothy; Sutter, Brad; Cabane, Michel; Coscia, David; Israël, Guy; Szopa, Cyril; Dromart, Gilles; Robert, François; Sautter, Violaine; Le Mouélic, Stéphane; Mangold, Nicolas; Nachon, Marion; Buch, Arnaud; Stalport, Fabien; Coll, Patrice; François, Pascaline; Raulin, François; Teinturier, Samuel; Cameron, James; Clegg, Sam; Cousin, Agnès; DeLapp, Dorothea; Dingler, Robert; Jackson, Ryan Steele; Johnstone, Stephen; Lanza, Nina; Little, Cynthia; Nelson, Tony; Wiens, Roger C.; Williams, Richard B.; Jones, Andrea; Kirkland, Laurel; Treiman, Allan; Baker, Burt; Cantor, Bruce; Caplinger, Michael; Davis, Scott; Duston, Brian; Edgett, Kenneth; Fay, Donald; Hardgrove, Craig; Harker, David; Herrera, Paul; Jensen, Elsa; Kennedy, Megan R.; Krezoski, Gillian; Krysak, Daniel; Lipkaman, Leslie; Malin, Michael; McCartney, Elaina; McNair, Sean; Nixon, Brian; Posiolova, Liliya; Ravine, Michael; Salamon, Andrew; Saper, Lee; Stoiber, Kevin; Supulver, Kimberley; Van Beek, Jason; Van Beek, Tessa; Zimdar, Robert; French, Katherine Louise; Iagnemma, Karl; Miller, Kristen; Summons, Roger; Goesmann, Fred; Goetz, Walter; Hviid, Stubbe; Johnson, Micah; Lefavor, Matthew; Lyness, Eric; Breves, Elly; Dyar, M. Darby; Fassett, Caleb; Blake, David F.; Bristow, Thomas; DesMarais, David; Edwards, Laurence; Haberle, Robert; Hoehler, Tori; Hollingsworth, Jeff; Kahre, Melinda; Keely, Leslie; McKay, Christopher; Wilhelm, Mary Beth; Bleacher, Lora; Brinckerhoff, William; Choi, David; Conrad, Pamela; Dworkin, Jason P.; Floyd, Melissa; Freissinet, Caroline; Garvin, James; Glavin, Daniel; Harpold, Daniel; Jones, Andrea; Mahaffy, Paul; Martin, David K.; McAdam, Amy; Pavlov, Alexander; Raaen, Eric; Smith, Michael D.; Stern, Jennifer; Tan, Florence; Trainer, Melissa; Meyer, Michael; Voytek, Mary; Anderson, Robert C.; Aubrey, Andrew; Beegle, Luther W.; Behar, Alberto; Blaney, Diana; Calef, Fred; Christensen, Lance; Crisp, Joy A.; DeFlores, Lauren; Ehlmann, Bethany; Feldman, Jason; Feldman, Sabrina; Flesch, Gregory; Hurowitz, Joel; Jun, Insoo; Keymeulen, Didier; Maki, Justin; Mischna, Michael; Morookian, John Michael; Parker, Timothy; Pavri, Betina; Schoppers, Marcel; Sengstacken, Aaron; Simmonds, John J.; Spanovich, Nicole; Juarez, Manuel de la Torre; Webster, Christopher R.; Yen, Albert; Archer, Paul Douglas; Jones, John H.; Ming, Douglas; Morris, Richard V.; Niles, Paul; Rampe, Elizabeth; Nolan, Thomas; Fisk, Martin; Radziemski, Leon; Barraclough, Bruce; Bender, Steve; Berman, Daniel; Dobrea, Eldar Noe; Tokar, Robert; Vaniman, David; Williams, Rebecca M. E.; Yingst, Aileen; Lewis, Kevin; Leshin, Laurie; Cleghorn, Timothy; Huntress, Wesley; Manhès, Gérard; Hudgins, Judy; Olson, Timothy; Stewart, Noel; Sarrazin, Philippe; Grant, John; Vicenzi, Edward; Wilson, Sharon A.; Hamilton, Victoria; Peterson, Joseph; Fedosov, Fedor; Golovin, Dmitry; Karpushkina, Natalya; Kozyrev, Alexander; Litvak, Maxim; Malakhov, Alexey; Mitrofanov, Igor; Mokrousov, Maxim; Nikiforov, Sergey; Prokhorov, Vasily; Sanin, Anton; Tretyakov, Vladislav; Varenikov, Alexey; Vostrukhin, Andrey; Kuzmin, Ruslan; Clark, Benton; Wolff, Michael; McLennan, Scott; Botta, Oliver; Drake, Darrell; Bean, Keri; Lemmon, Mark; Schwenzer, Susanne P.; Anderson, Ryan B.; Herkenhoff, Kenneth; Lee, Ella Mae; Sucharski, Robert; Hernández, Miguel Ángel de Pablo; Ávalos, Juan José Blanco; Ramos, Miguel; Malespin, Charles; Plante, Ianik; Muller, Jan-Peter; Navarro-González, Rafael; Ewing, Ryan; Boynton, William; Downs, Robert; Fitzgibbon, Mike; Harshman, Karl; Morrison, Shaunna; Dietrich, William; Kortmann, Onno; Palucis, Marisa; Sumner, Dawn Y.; Williams, Amy; Lugmair, Günter; Wilson, Michael A.; Rubin, David; Jakosky, Bruce; Balic-Zunic, Tonci; Frydenvang, Jens; Jensen, Jaqueline Kløvgaard; Kinch, Kjartan; Koefoed, Asmus; Madsen, Morten Bo; Stipp, Susan Louise Svane; Boyd, Nick; Campbell, John L.; Gellert, Ralf; Perrett, Glynis; Pradler, Irina; VanBommel, Scott; Jacob, Samantha; Owen, Tobias; Rowland, Scott; Atlaskin, Evgeny; Savijärvi, Hannu; García, César Martín; Mueller-Mellin, Reinhold; Bridges, John C.; McConnochie, Timothy; Benna, Mehdi; Franz, Heather; Bower, Hannah; Brunner, Anna; Blau, Hannah; Boucher, Thomas; Carmosino, Marco; Atreya, Sushil; Elliott, Harvey; Halleaux, Douglas; Rennó, Nilton; Wong, Michael; Pepin, Robert; Elliott, Beverley; Spray, John; Thompson, Lucy; Gordon, Suzanne; Newsom, Horton; Ollila, Ann; Williams, Joshua; Vasconcelos, Paulo; Bentz, Jennifer; Nealson, Kenneth; Popa, Radu; Kah, Linda C.; Moersch, Jeffrey; Tate, Christopher; Day, Mackenzie; Kocurek, Gary; Hallet, Bernard; Sletten, Ronald; Francis, Raymond; McCullough, Emily; Cloutis, Ed; ten Kate, Inge Loes; Kuzmin, Ruslan; Arvidson, Raymond; Fraeman, Abigail; Scholes, Daniel; Slavney, Susan; Stein, Thomas; Ward, Jennifer; Berger, Jeffrey; Moores, John E.

    2014-01-01

    The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.

  13. Radiation environment assessment, measurement and its impact on health and sustainable development

    International Nuclear Information System (INIS)

    Kumar, Pradeep; Panwar, Brijandra Singh

    2012-01-01

    Present paper deals with Radiation Environment Assessment, Measurement and its Impact on Health, its meaning and in particular with sustainable development perspective. Health and Environment appears to be different subjects and concepts, but in reality they are interrelated and interdependent. One cannot exist without the other. For good health hygienic environment is a sine qua non. Article 3 of Universal Declaration of Human Right 1948 incorporates the right to life. It has been interpreted by the international court that the word life does not means simply to live but it means to live with dignity and in well and pollution and radiation free environment which is a gift of nature on this universe. There is no doubt about the nuclear revolution that has taken place and has made life of human beings worth living on this earth with comfort. It is growing development of the nation. But in the process the development that has been done at the cost of human life, public health and environment which will prove fatal in the long run. So there is a need for Sustainable Development of the human and environment of the world. Precisely and concisely, the sustainable development is a process that meets the needs of the present without compromising ability of future generations to meet their own needs. A hygienic and redaction free environment will ensure the better Health of the people. Environment and nuclear power plant can coexist. The harmonization of the two needs has led to the concept of Radiation Environment Assessment and sustainable development, so much so that it has become the most significant and focal point of environmental legislation relating to the same. Sustainable development, simply put, is a process in which development can be sustained over generations effects of radiation on humans and on the environment. Finally, this paper deals with the impact of radiation on environment and the need of sustainable development for achieving a better human. (author)

  14. Radiation Safety Management Guidelines for PET-CT: Focus on Behavior and Environment

    International Nuclear Information System (INIS)

    Jung, Jin Wook; Han, Eun Ok

    2011-01-01

    Our purpose is to specify behavior and environmental factors aimed at reducing the exposed dosage caused by PET-CT and to develop radiation safety management guidelines adequate for domestic circumstances. We have used a multistep-multimethod as the methodological approach to design and to carry out the research both in quality and quantity, including an analysis on previous studies, professional consultations and a survey. The survey includes responses from 139 practitioners in charged of 109 PET-CTs installed throughout Korea(reported by the Korean Society of Nuclear Medicine, 2010). The research use 156 questions using Cronbach's α (alpha) coefficients which were: 0.818 for 'the necessity of setting and installing the radiation protective environment'; 0.916 for 'the necessity of radiation protection', 'setting and installing the radiation protective environment'; and 0.885 for 'radiation protection'. The check list, derived from the radiation safety management guidelines focused on behavior and environment, was composed of 20 items for the radiation protective environment: including 5 items for the patient; 4 items for the guardian; 3 items for the radiologist; and 8 items applied to everyone involved; for a total of 26 items for the radiation protective behavior including: 12 items for the patient; 1 item for the guardian, 7 items for the radiologist; and 6 items applied to everyone involved. The specific check list is shown in (Table 5-6). Since our country has no safety management guidelines of its own to reduce the exposed dosage caused by PET-CTs, we believe the guidelines developed through this study means great deal to the field as it is not only appropriate for domestic circumstances, but also contains specific check lists for each target who may be exposed to radiation in regards to behavior and environment.

  15. Background radiation, people and the environment: a review

    International Nuclear Information System (INIS)

    Ramachandran, T.V.

    2007-01-01

    All living organisms are exposed to ionizing radiation, which always existed naturally. Important sources are cosmic rays which comes from outer space and from the surface of the sun, terrestrial radionuclides which occurs in the earth's crust, in building materials and in air, water and foods and in the human body itself. Some of the exposures are fairly constant and uniform for all individuals everywhere, for example, the dose from ingestion of potassium-40 in food. Other exposures vary depending on location. Cosmic rays, for example are, more intense at higher altitudes, and the concentrations of uranium and thorium in soils are elevated in localized areas. Exposures can also vary as a result of human activities and practices. In particular, the building materials of houses and the design and ventilation systems strongly influences the indoor levels of the radioactive gas radon and its decay products, which contributes significantly to doses through inhalation. Component of the sources of exposures to Indian population has been assessed based on the data generated. Total contribution to the natural sources to the Indian population works out to 2.3 mSv/y as against the global value of 2.4 mSv/y. Estimated modified source which includes mining of heavy metals, coal fired power plants, mining of phosphate rocks and its use as fertilizers, production of natural gas, production of gas mantles and luminescent dial and air travel contribution to the background radiation to the Indian population works out to be 1.2 x 10 -3 mSv/y; while atmospheric weapon tests contributes about 0.045 mSv/y, medical exposure contributes about 0.048 mSv/y and exposure due to nuclear power production contributes about 5.0 x 10 -5 mSv/y to the background radiation. Brief review and comparison of the dose rates arising from natural and man made sources to the Indian population is given. (author)

  16. Predictions of energetic particle radiation in the close Martian environment

    Science.gov (United States)

    McKenna-Lawlor, Susan M. P.; Dryer, M.; Fry, C. D.; Sun, W.; Lario, D.; Deehr, C. S.; Sanahuja, B.; Afonin, V. A.; Verigin, M. I.; Kotova, G. A.

    2005-03-01

    Intense, prolonged solar flare activity during March 1989 was used to provide a retrospective scenario for predictions of associated interplanetary shocks and accompanying particle radiation at planet Mars. Shocks from five major flares were simulated to hit both the Earth and Mars during the interval 9-23 March 1989. The simulated scenario was provided by the Hakamada-Akasofu-Fry version 2 (HAFv.2) solar wind model. Since part of the generally required inputs for the model (specifically metric radio Type II coronal shock speeds) were not available, the shock speeds were iteratively determined via a "calibration" that uses limited IMP 8 particle and sudden storm commencement (SSC) data as proxies for shock arrival at the Earth. The shocks from four major solar flares were, thereby, found to arrive at Mars at times that are appropriate to explain solar energetic particle (SEP) and energetic storm particle (ESP) events recorded in situ by the particle radiation detector experiments Solar Low Energy Detector (SLED) and Low Energy Telescope (LET) aboard Phobos-2. Supporting measurements were provided by the magnetometer (MAGMA) and plasma spectrometer (TAUS) experiments. A gap in the spacecraft records occurred at the simulated time of arrival of the fifth flare-associated shock. There were some uncertainties attending the selection of certain of the events deemed to be "parent" flares. Such uncertainty can be expected in view of the incomplete set of energetic particle, plasma, and magnetic field measurements made at relevant times at both the Earth and Mars (the latter planet was then located at a distance of 1.6 AU, at about 78° east of the Sun-Earth line). Use of the HAFv.2 solar wind model affords a 4-day lead time between predicted and measured space weather events at Mars, with an error of approximately ±12 hours. Solar radiation events of the magnitude studied occur often enough to warrant consideration in the design of both manned and unmanned expeditions to

  17. Measurement and simulation of the radiation environment in the lower atmosphere for dose assessment

    International Nuclear Information System (INIS)

    Pioch, Christian Dieter

    2012-01-01

    Flying personnel is occupationally exposed to rather high radiation levels due to secondary cosmic radiation. Therefore, the radiation environment induced in the lower atmosphere by galactic and solar cosmic radiation was characterized by means of particle transport calculations using GEANT4. These calculations were validated with continuous measurements of the energy spectra of secondary neutrons with Bonner sphere spectrometers at the Zugspitze mountain and near the North Pole. The response of these instruments was determined with GEANT4 and for the first time experimentally verified at high neutron energies (244 and 387 MeV). Route doses for aircrews along typical long-haul flights were determined for galactic and solar cosmic radiation using most recent data on the magnetospheric field and primary cosmic radiation.

  18. Prediction of LDEF exposure to the ionizing radiation environment

    Science.gov (United States)

    Watts, J. W.; Armstrong, T. W.; Colborn, B. L.

    1996-01-01

    Predictions of the LDEF mission's trapped proton and electron and galactic cosmic ray proton exposures have been made using the currently accepted models with improved resolution near mission end and better modeling of solar cycle effects. An extension of previous calculations, to provide a more definitive description of the LDEF exposure to ionizing radiation, is represented by trapped proton and electron flux as a function of mission time, presented considering altitude and solar activity variation during the mission and the change in galactic cosmic ray proton flux over the mission. Modifications of the AP8MAX and AP8MIN fluence led to a reduction of fluence by 20%. A modified interpolation model developed by Daly and Evans resulted in 30% higher dose and activation levels, which better agreed with measured values than results predicted using the Vette model.

  19. Radiation Environment Model of Protons and Heavier Ions at Jupiter

    Science.gov (United States)

    Sierra, Luz Maria Martinez; Garrett, Henry B.; Jun, Insoo

    2015-01-01

    We performed an in depth study of the methods used to review the geometric factors (GF) and sensitivity to charge particles of the Energetic Particle Detector instrument on board the Galileo Spacecraft. Monte Carlo simulations were performed to understand the interactions of electrons and ions (i. e., protons and alphas) with the sensitive regions of the instrument. The DC0 and B0 channels were studied with the intention of using them to update the jovian proton radiation model. The results proved that the B0 is a clean proton chanel without any concerns for contamination by heavier ions and electrons. In contrast, DC0 was found to be contaminated by electrons. Furthermore, we also found out that the B2 channel is a clean alpha particle channel (in other words, no contamination by electrons and/or protons).

  20. Measurement of radionuclides in the environment via Cherenkov radiation

    International Nuclear Information System (INIS)

    Ross, H.H.

    1987-01-01

    The author has developed an alternate approach to the measurement of some beta-emitting nuclides that utilizes the luminescence generated by the Cherenkov process. The luminescence, now known as Cherenkov radiation, was shown to be generated when a charged particle passes through a transparent medium at a speed that exceeds the phase velocity of light in the same medium. Cherenkov emission is different from most other luminescence processes in that it is a purely physical phenomenon. One consequence of this is that Cherenkov systems are free of chemical quenching effects. Conventional methods of analysis for environmental levels of beta-emitting radionuclides are often tedious, time-consuming, and expensive. The Cherenkov method is fast, requires very little operator attention, and is much less expensive to perform

  1. Environmental gamma radiation monitoring in the environs of Kudankulam Nuclear Power Project (KKNPP), Tamil Nadu, India

    International Nuclear Information System (INIS)

    Takale, R.A.; Shetty, P.G.; Swarnkar, M.; Sahu, S.K.; Pandit, G.G.; Puranik, V.D.

    2011-01-01

    In the recent years continuous monitoring of natural background radiation has become a major concern. Protection of the environment against radiation is given top priority in the development of Indian nuclear power programme. Thermoluminescent Dosimeters(TLD) usage is an important factor in this type of activity as it gives integrated dose over a period of time and do not require constant manual attendance or other infrastructural facilities like electricity. Keeping this in view pre-operational background gamma radiation survey around Kudankulam Nuclear Power Project (KKNPP) was initiated in 2003 using TLDs. Thirty five environmental TLDs are placed in and around different directions at various distances from the plant on a quarterly basis. These quarterly dose values are converted into annual values and the analysis has been carried out. This paper summarizes the background natural radiation levels in the KKNPP environs during the periods 2003-2010 in order to have knowledge on the increase if any, of the environmental radiation levels when the plant will be in operation. It was observed that the natural background gamma radiation levels in and around Kudankulam varied between 0.67-2.94 mGy/a. In general, the background gamma radiation levels at a given location are steady, typically within 20%, although there is a large location to location variation in the background gamma radiation levels owing to the fact that the region shows varying primordial radioactivity concentration particularly thorium. (author)

  2. Hazards of ionizing radiations for human beings and environment with respect to nuclear facilities

    International Nuclear Information System (INIS)

    Huebner, Felix; Jung, Jennifer Jana; Schultmann, Frank

    2017-01-01

    Worldwide, nuclear fission is used to produce electricity. On the one hand, the low emission of CO 2 is often mentioned as an advantage of this technology. On the other hand, warnings about the dangers of nuclear fission are mentioned. Consequently, an overview about the dangers of ionizing radiation to human beings as well as animals and the environment is important. However, the focus will be on possible health effects for humans with regards to nuclear power plants. In nuclear power plants, both natural types of radiation and artificially produced radiation occur. During normal operation, it is possible that small quantities of this ionizing radiation are released to the environment. In case of nuclear disasters or faults during decommissioning and dismantling processes the consequences of thereby emitted quantities can be even more severe. Reference nuclides vary by reactor type, operating stage and respective incident. At the beginning, different types of radiation and their characteristics and effects on the affected organism are explained. Sensitive organs are emphasized in this context. The individual risk is determined by numerous factors and therefore cannot be predicted. Based on scientific studies and medical publications the hazards of ionizing radiation are compiled. Effects of high exposure of ionizing radiation are well-investigated. Scientists are still divided over the connection between several diseases and the exposure to low doses of ionizing radiation. For this reason, the positions of different international organizations are critically contrasted in this study.

  3. The Los Alamos dynamic radiation environment assimilation model (DREAM) for space weather specification and forecasting

    Energy Technology Data Exchange (ETDEWEB)

    Reeves, Geoffrey D [Los Alamos National Laboratory; Friedel, Reiner H W [Los Alamos National Laboratory; Chen, Yue [Los Alamos National Laboratory; Koller, Josef [Los Alamos National Laboratory; Henderson, Michael G [Los Alamos National Laboratory

    2008-01-01

    The Dynamic Radiation Environment Assimilation Model (DREAM) was developed at Los Alamos National Laboratory to assess, quantify, and predict the hazards from the natural space environment and the anthropogenic environment produced by high altitude nuclear explosions (HANE). DREAM was initially developed as a basic research activity to understand and predict the dynamics of the Earth's Van Allen radiation belts. It uses Kalman filter techniques to assimilate data from space environment instruments with a physics-based model of the radiation belts. DREAM can assimilate data from a variety of types of instruments and data with various levels of resolution and fidelity by assigning appropriate uncertainties to the observations. Data from any spacecraft orbit can be assimilated but DREAM was designed to function with as few as two spacecraft inputs: one from geosynchronous orbit and one from GPS orbit. With those inputs, DREAM can be used to predict the environment at any satellite in any orbit whether space environment data are available in those orbits or not. Even with very limited data input and relatively simple physics models, DREAM specifies the space environment in the radiation belts to a high level of accuracy. DREAM has been extensively tested and evaluated as we transition from research to operations. We report here on one set of test results in which we predict the environment in a highly-elliptical polar orbit. We also discuss long-duration reanalysis for spacecraft design, using DREAM for real-time operations, and prospects for 1-week forecasts of the radiation belt environment.

  4. Methodology for estimating radiation dose rates to freshwater biota exposed to radionuclides in the environment

    International Nuclear Information System (INIS)

    Blaylock, B.G.; Frank, M.L.; O'Neal, B.R.

    1993-08-01

    The purpose of this report is to present a methodology for evaluating the potential for aquatic biota to incur effects from exposure to chronic low-level radiation in the environment. Aquatic organisms inhabiting an environment contaminated with radioactivity receive external radiation from radionuclides in water, sediment, and from other biota such as vegetation. Aquatic organisms receive internal radiation from radionuclides ingested via food and water and, in some cases, from radionuclides absorbed through the skin and respiratory organs. Dose rate equations, which have been developed previously, are presented for estimating the radiation dose rate to representative aquatic organisms from alpha, beta, and gamma irradiation from external and internal sources. Tables containing parameter values for calculating radiation doses from selected alpha, beta, and gamma emitters are presented in the appendix to facilitate dose rate calculations. The risk of detrimental effects to aquatic biota from radiation exposure is evaluated by comparing the calculated radiation dose rate to biota to the U.S. Department of Energy's (DOE's) recommended dose rate limit of 0.4 mGy h -1 (1 rad d -1 ). A dose rate no greater than 0.4 mGy h -1 to the most sensitive organisms should ensure the protection of populations of aquatic organisms. DOE's recommended dose rate is based on a number of published reviews on the effects of radiation on aquatic organisms that are summarized in the National Council on Radiation Protection and Measurements Report No. 109 (NCRP 1991). DOE recommends that if the results of radiological models or dosimetric measurements indicate that a radiation dose rate of 0. 1 mGy h -1 will be exceeded, then a more detailed evaluation of the potential ecological consequences of radiation exposure to endemic populations should be conducted

  5. Methodology for estimating radiation dose rates to freshwater biota exposed to radionuclides in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, B.G.; Frank, M.L.; O`Neal, B.R.

    1993-08-01

    The purpose of this report is to present a methodology for evaluating the potential for aquatic biota to incur effects from exposure to chronic low-level radiation in the environment. Aquatic organisms inhabiting an environment contaminated with radioactivity receive external radiation from radionuclides in water, sediment, and from other biota such as vegetation. Aquatic organisms receive internal radiation from radionuclides ingested via food and water and, in some cases, from radionuclides absorbed through the skin and respiratory organs. Dose rate equations, which have been developed previously, are presented for estimating the radiation dose rate to representative aquatic organisms from alpha, beta, and gamma irradiation from external and internal sources. Tables containing parameter values for calculating radiation doses from selected alpha, beta, and gamma emitters are presented in the appendix to facilitate dose rate calculations. The risk of detrimental effects to aquatic biota from radiation exposure is evaluated by comparing the calculated radiation dose rate to biota to the U.S. Department of Energy`s (DOE`s) recommended dose rate limit of 0.4 mGy h{sup {minus}1} (1 rad d{sup {minus}1}). A dose rate no greater than 0.4 mGy h{sup {minus}1} to the most sensitive organisms should ensure the protection of populations of aquatic organisms. DOE`s recommended dose rate is based on a number of published reviews on the effects of radiation on aquatic organisms that are summarized in the National Council on Radiation Protection and Measurements Report No. 109 (NCRP 1991). DOE recommends that if the results of radiological models or dosimetric measurements indicate that a radiation dose rate of 0. 1 mGy h{sup {minus}1} will be exceeded, then a more detailed evaluation of the potential ecological consequences of radiation exposure to endemic populations should be conducted.

  6. A Monte Carlo transport code study of the space radiation environment using FLUKA and ROOT

    CERN Document Server

    Wilson, T; Carminati, F; Brun, R; Ferrari, A; Sala, P; Empl, A; MacGibbon, J

    2001-01-01

    We report on the progress of a current study aimed at developing a state-of-the-art Monte-Carlo computer simulation of the space radiation environment using advanced computer software techniques recently available at CERN, the European Laboratory for Particle Physics in Geneva, Switzerland. By taking the next-generation computer software appearing at CERN and adapting it to known problems in the implementation of space exploration strategies, this research is identifying changes necessary to bring these two advanced technologies together. The radiation transport tool being developed is tailored to the problem of taking measured space radiation fluxes impinging on the geometry of any particular spacecraft or planetary habitat and simulating the evolution of that flux through an accurate model of the spacecraft material. The simulation uses the latest known results in low-energy and high-energy physics. The output is a prediction of the detailed nature of the radiation environment experienced in space as well a...

  7. Organization and operation of the Sixth International Symposium on the Natural Radiation Environment (NRE VI)

    International Nuclear Information System (INIS)

    Hopke, P.K.

    1996-01-01

    An important source of human exposure to radiation is the natural world including cosmic rays, cosmogenic radionuclides, natural terrestrial radionuclides, and radon isotopes and its decay products. Considerable effort is being expended on a worldwide basis to characterize the exposure to the natural radiation environment and determine the important pathways for the exposure to result in the dose to tissue that leads to injury and disease. The problem of background exposure to naturally occurring radioactivity has been the subject of research since the initial discovery of the radioactivity of uranium and thorium. However, with the advent of artificial sources of radiation with both benefits and harm the nature and magnitude of the natural radiation environment and the effects on various populations are important in the development of overall public health strategies as ALARA principles are applied to the situation

  8. RADIATION HEAT TRANSFER ENVIRONMENT IN FIRE AND FURNACE TESTS OF RADIOACTIVE MATERIALS PACKAGES

    International Nuclear Information System (INIS)

    Smith, A.

    2008-01-01

    The Hypothetical Accident Conditions (HAC) sequential test of radioactive materials packages includes a thermal test to confirm the ability of the package to withstand a transportation fire event. The test specified by the regulations (10 CFR 71) consists of a 30 minute, all engulfing, hydrocarbon fuel fire, with an average flame temperature of at least 800 C. The requirements specify an average emissivity for the fire of at least 0.9, which implies an essentially black radiation environment. Alternate test which provide equivalent total heat input at the 800 C time averaged environmental temperature may also be employed. When alternate tests methods are employed, such as furnace or gaseous fuel fires, the equivalence of the radiation environment may require justification. The effects of furnace and open confinement fire environments are compared with the regulatory fire environment, including the effects of gases resulting from decomposition of package overpack materials. The results indicate that furnace tests can produce the required radiation heat transfer environment, i.e., equivalent to the postulated pool fire. An open enclosure, with transparent (low emissivity) fire does not produce an equivalent radiation environment

  9. Modeling Background Radiation in our Environment Using Geochemical Data

    Energy Technology Data Exchange (ETDEWEB)

    Malchow, Russell L.; Marsac, Kara [University of Nevada, Las Vegas; Burnley, Pamela [University of Nevada, Las Vegas; Hausrath, Elisabeth [Uniiversity of Nevada, Las Vegas; Haber, Daniel [University of Nevada, Las Vegas; Adcock, Christopher [University of Nevada, Las Vegas

    2015-02-01

    Radiation occurs naturally in bedrock and soil. Gamma rays are released from the decay of the radioactive isotopes K, U, and Th. Gamma rays observed at the surface come from the first 30 cm of rock and soil. The energy of gamma rays is specific to each isotope, allowing identification. For this research, data was collected from national databases, private companies, scientific literature, and field work. Data points were then evaluated for self-consistency. A model was created by converting concentrations of U, K, and Th for each rock and soil unit into a ground exposure rate using the following equation: D=1.32 K+ 0.548 U+ 0.272 Th. The first objective of this research was to compare the original Aerial Measurement System gamma ray survey to results produced by the model. The second objective was to improve the method and learn the constraints of the model. Future work will include sample data analysis from field work with a goal of improving the geochemical model.

  10. Radiation Protection of Environment under the Light of the New Concept of Radiation Protection of Non-Human Species

    Energy Technology Data Exchange (ETDEWEB)

    Hansruedi Voelkle [Swiss Federal Office of Public Health, Environmental Radioactivity Section, c/o Physics Department, University of Fribourg Chemin du Musee 3, 1700 Fribourg (Switzerland)

    2006-07-01

    The purpose of this presentation is to discuss the question of whether radiation protection should be extended to plants and animals. Until now the recommendations of ICRP have been focused exclusively on the protection of man from ionizing radiation. It was assumed that, if man is protected, the quality of the living environment is not impaired. In recent years adequate principles, recommendations and laws have become necessary in order to protect the environment from man made toxins. These recommendations aimed to conserve plants and animals, to maintain the diversity of species, the health and status of natural habitats and the natural resources of our planet, to warrant natural evolution and selection processes in order to transmit a healthy world to future generations. Reflections have been made as to whether particular protection of fauna and flora from ionizing radiation should be included. This article presents some considerations from the point of view of operational radiation protection and some comments to the work already done by ICRP committee 5. The final purpose is to invite the audience to make its own reflections and to communicate any criticisms, comments or suggestions to committee 5 of ICRP. (author)

  11. Radiation Protection of Environment under the Light of the New Concept of Radiation Protection of Non-Human Species

    International Nuclear Information System (INIS)

    Hansruedi Voelkle

    2006-01-01

    The purpose of this presentation is to discuss the question of whether radiation protection should be extended to plants and animals. Until now the recommendations of ICRP have been focused exclusively on the protection of man from ionizing radiation. It was assumed that, if man is protected, the quality of the living environment is not impaired. In recent years adequate principles, recommendations and laws have become necessary in order to protect the environment from man made toxins. These recommendations aimed to conserve plants and animals, to maintain the diversity of species, the health and status of natural habitats and the natural resources of our planet, to warrant natural evolution and selection processes in order to transmit a healthy world to future generations. Reflections have been made as to whether particular protection of fauna and flora from ionizing radiation should be included. This article presents some considerations from the point of view of operational radiation protection and some comments to the work already done by ICRP committee 5. The final purpose is to invite the audience to make its own reflections and to communicate any criticisms, comments or suggestions to committee 5 of ICRP. (author)

  12. Evaluation of Planck mean coefficients for particle radiative properties in combustion environments

    Science.gov (United States)

    Hofgren, Henrik; Sundén, Bengt

    2015-04-01

    Thermal radiation is the dominating form of heat transfer in several combustion technologies that combust solid fuels, such as pulverized coal combustion and fixed bed combustion. The thermal radiation originates from the hot combustion gases and particles. For accurate modelling of thermal radiation in these environments the selection of the radiative transport model and radiative property model is important. Radiative property models for gases have received huge attention and several well documented models exist. For particles, soot has received considerable attention whereas other particles have not to a similar extent. The Planck mean coefficients are most commonly used to describe the radiative properties of the particles. For gases the Planck mean absorption coefficient is known to give large deviations from recognised exact models in predicting the radiative heat transfer. In this study the use of Planck mean coefficients for particles are investigated and compared to spectral models. Two particle mass size distributions of fly ash are used, representing biomass and coal combustion. The evaluation is conducted in several combustion-like test cases with both gases and particles. The evaluation shows that using Planck mean coefficients for particles, in combustion-like situations, can give large errors in predicting the radiative heat flux and especially the source term. A new weighted sum of grey gas approach is tested and evaluated. It includes both the particles and gases to better account for the non-greyness of the fly ash absorption coefficient.

  13. Interactive Visual Intervention Planning: Interactive Visualization for Intervention Planning in Particle Accelerator Environments with Ionizing Radiation

    CERN Document Server

    Fabry, Thomas; Feral, Bruno

    2013-01-01

    Intervention planning is crucial for maintenance operations in particle accelerator environments with ionizing radiation, during which the radiation dose contracted by maintenance workers should be reduced to a minimum. In this context, we discuss the visualization aspects of a new software tool, which integrates interactive exploration of a scene depicting an accelerator facility augmented with residual radiation level simulations, with the visualization of intervention data such as the followed trajectory and maintenance tasks. The visualization of each of these aspects has its effect on the final predicted contracted radiation dose. In this context, we explore the possible benefits of a user study, with the goal of enhancing the visual conditions in which the intervention planner using the software tool is minimizing the radiation dose.

  14. Are biological effects of space radiation really altered under the microgravity environment?

    Science.gov (United States)

    Yatagai, Fumio; Ishioka, Noriaki

    2014-10-01

    Two major factors of space environment are space radiation and microgravity. It is generally considered that a high level of ionizing radiation (IR) in space has an influence on living organisms including humans; therefore, the possible alteration of space-radiation influences by the microgravity environment is of great concern. In fact, examination of such a possibility has been extensively conducted since the early days of space experiments, suggesting a possible synergistic effect of radiation and microgravity in some experiments but a negative observation in others. Because these complicated results remain not well understood, we propose a solution to this problem. Gene expression analysis is one of the solutions to the problem. In fact, gene expression may be changed by microgravity, and further modification may be possible through IR. This result could reveal an interactive effect of both factors on the cellular responses, which could in turn reveal whether the human-health abnormalities expected under the microgravity environment can be altered by space radiation. We believe that this is a new aspect in the study of the interactive effect of radiation and microgravity. However, further improvements in space experimental technologies are required for future studies.

  15. Reliability evaluation of ACP components under a radiation environment

    International Nuclear Information System (INIS)

    Lee, Hyo Jik; Yoon, Kwang Ho; Lim, Kwang Mook; Park, Byung Suk; Yoon, Ji Sup

    2007-01-01

    This study deals with the irradiation effects on some selected components which are being used in an Advanced Spent Fuel Conditioning Process (ACP). Irradiation test components have a higher priority from the aspect of their reliability because their degradation or failure is able to critically affect the performance of an ACP equipment. Components that we chose for the irradiation tests were the AC servo motor, potentiometer, thermocouples, accelerometer and CCD camera. ACP facility has a number of AC servo motors to move the joints of a manipulator and to operate process equipment. Potentiometers are used for a measurement of several joint angles in a manipulator. Thermocouples are used for a temperature measurement in an electrolytic reduction reactor, a voloxidation reactor and a molten salt transfer line. An accelerometer is installed in a slitting machine to forecast an incipient failure during a slitting process. A small CCD camera is used for an in-situ vision monitoring between ACP campaigns. We made use of a gamma-irradiation facility with cobalt-60 source for an irradiation test on the above components because gamma rays from among various radioactive rays are the most significant for electric, electronic and robotic components. Irradiation tests were carried our for enough long time for total doses to be over expected threshold values. Other components except the CCD camera showed a very high radiation hardening characteristic. Characteristic changes at different total doses were investigated and threshold values to warrant at least their performance without a deterioration were evaluated as a result of the irradiation tests

  16. Estimating the solar radiation environment on the soil surface between rows using crop canopy architectural models

    International Nuclear Information System (INIS)

    Yuge, K.; Haraguchi, T.; Nakano, Y.; Kuroda, M.; Funakoshi, T.

    2002-01-01

    The objective of this study is quantification of the solar radiation in the farmland located in the hilly and mountainous areas, considering the effect of the shelter adjacent to the field, such as the forest (This effect is called as the edge-effect in this study.). To evaluate the edge-effect on the solar radiation environment in the farmland, solar radiations are measured at the center and edge of the study site adjacent to the forest. The simulation model is composed, coupling with the fish-eye projection method and procedure for the separating direct and diffuse solar radiations. Using this model, the diurnal solar radiations are simulated at the center and edge of the study site. The simulation result showed good agreement with the observation. The spatial distribution of the solar radiation in an observational field is quantified by this method, considering the edge-effect. The simulation result indicated that the solar radiation environment on the field surface is affected by the shelter adjacent to the field and the field direction. (author)

  17. Radiation-Induced Damage and Recovery of Ultra-Nanocrystalline Diamond: Toward Applications in Harsh Environments.

    Science.gov (United States)

    Martin, Aiden A; Filevich, Jorge; Straw, Marcus; Randolph, Steven; Botman, Aurélien; Aharonovich, Igor; Toth, Milos

    2017-11-15

    Ultra-nanocrystalline diamond (UNCD) is increasingly being used in the fabrication of devices and coatings due to its excellent tribological properties, corrosion resistance, and biocompatibility. Here, we study its response to irradiation with kiloelectronvolt electrons as a controlled model for extreme ionizing environments. Real time Raman spectroscopy reveals that the radiation-damage mechanism entails dehydrogenation of UNCD grain boundaries, and we show that the damage can be recovered by annealing at 883 K. Our results have significant practical implications for the implementation of UNCD in extreme environment applications, and indicate that the films can be used as radiation sensors.

  18. The resolved stellar population of Leo A

    NARCIS (Netherlands)

    Tolstoy, E

    1996-01-01

    New observations of the resolved stellar population of the extremely metal-poor Magellanic dwarf irregular galaxy Leo A in Thuan-Gunn r, g, i, and narrowband Ha filters are presented. Using the recent Cepheid variable star distance determination to Leo A by Hoessel et al., we are able to create an

  19. Creation of Leo LT postponed yet again

    Index Scriptorium Estoniae

    2008-01-01

    Valitsusega koos investeerimisfirmat Leo LT loova ettevõtte NDX Energija esindaja Ignas Staskevicius ei välista ka projektist loobumist, kuna lepingute tegemine on jäänud venima. Investeerimisfirma Leo LT ülesandeks on ehitada Leedu uus tuumajaam

  20. The Ultraviolet Radiation Environment around M Dwarf Exoplanet Host Stars

    Science.gov (United States)

    France, Kevin; Froning, Cynthia S.; Linsky, Jeffrey L.; Roberge, Aki; Stocke, John T.; Tian, Feng; Bushinsky, Rachel; Desert, Jean-Michel; Mauas, Pablo; Mauas, Pablo; hide

    2013-01-01

    The spectral and temporal behavior of exoplanet host stars is a critical input to models of the chemistry and evolution of planetary atmospheres. Ultraviolet photons influence the atmospheric temperature profiles and production of potential biomarkers on Earth-like planets around these stars. At present, little observational or theoretical basis exists for understanding the ultraviolet spectra of M dwarfs, despite their critical importance to predicting and interpreting the spectra of potentially habitable planets as they are obtained in the coming decades. Using observations from the Hubble Space Telescope, we present a study of the UV radiation fields around nearby M dwarf planet hosts that covers both far-UV (FUV) and near-UV (NUV) wavelengths. The combined FUV+NUV spectra are publicly available in machine-readable format. We find that all six exoplanet host stars in our sample (GJ 581, GJ 876, GJ 436, GJ 832, GJ 667C, and GJ 1214) exhibit some level of chromospheric and transition region UV emission. No "UV-quiet" M dwarfs are observed. The bright stellar Lyman-alpha emission lines are reconstructed, and we find that the Lyman-alpha line fluxes comprise approximately 37%-75% of the total 1150-3100 A flux from most M dwarfs; approximately greater than 10(exp3) times the solar value. We develop an empirical scaling relation between Lyman-alpha and Mg II emission, to be used when interstellar H I attenuation precludes the direct observation of Lyman-alpha. The intrinsic unreddened flux ratio is F(Lyman-alpha)/F(Mg II) = 10(exp3). The F(FUV)/F(NUV) flux ratio, a driver for abiotic production of the suggested biomarkers O2 and O3, is shown to be approximately 0.5-3 for all M dwarfs in our sample, greather than 10(exp3) times the solar ratio. For the four stars with moderate signal-to-noise Cosmic Origins Spectrograph time-resolved spectra, we find UV emission line variability with amplitudes of 50%.500% on 10(exp2)-10(exp3) s timescales. This effect should be taken

  1. The radiation monitoring of environment around place of treatment and storage of radioactive wastes

    International Nuclear Information System (INIS)

    Vdovina, E.D.

    2001-01-01

    Full text: Large success was attained in the field of radiation protection of research nuclear center, but it is necessary to carry out works in this way around place of treatment and storage of radioactive wastes too. Moreover, for protection of environment it is necessary to control radiation condition of system (radioactive wastes of nuclear center - environment). There is large amount of natural and man-made radionuclides in environment and it is important to solve problem to control individual radionuclides, polluting natural environment. Also, it is necessary to control concentrations of specific radionuclides, which are marks of definite radioactive source. The radionuclides 137 Cs, 90 Sr, 60 Co, 141 Ce, 144 Ce, 95 Zr, 95 Nb, 131 I and natural radionuclides of uranium, thorium and their products of decay are basic radionuclides. The 57 Co, 35 S, 32 P are considered also basic radionuclides taking into consideration specialization of our Institute. The basic problems of control of environment are following: observation of radioactive pollution level of environment objects; estimation of radioactive pollution level with the purpose of warning of possible negative consequences; investigation of dynamics of radioactivity and prognosis of radioactive pollution of environment objects; influence on sources of radioactive pollution. There is large volume information, characterizing radiation condition of environment around research nuclear center and around place of treatment and storage of radioactive wastes. The bank of environment object analysis result date was build for investigation of information. The system of protection around location of treatment and storage of radioactive wastes and around nuclear center consists of control of radioactive wastes, superficial and underground water, soil, plants, atmospheric precipitation. There are analysis of total β- activity, α-activity and γ-spectrometry. This control includes estimation of throw down values

  2. Ethical considerations in protecting the environment from the effects of ionizing radiation. A report for discussion

    International Nuclear Information System (INIS)

    2002-02-01

    In recent years awareness of the vulnerability of the environment has increased and the need to protect it against the effects of industrial pollutants has been recognized. This trend is reflected in new and developing international policies for environmental protection. In the context of protection of the environment against ionizing radiation, the existing international approach is based on providing for the protection of humans. The current recommendations of the International Commission on Radiological Protection (ICRP) include the statement that t he standard of environmental control needed to protect man to the degree currently thought desirable will ensure that other species are not put at risk... . In the light of the new focus of concern for the environment, this statement is being critically reviewed in several international fora. The IAEA has, over many years, sponsored studies of the effects of ionizing radiation on species other than humans. Most recently it published a discussion report as IAEA-TECDOC-1091 (1999) in which the need for developing a system for protecting the environment against the effects of ionizing radiation was elaborated and in which various related technical and philosophical issues for resolution were discussed. The current report explores the ethical principles that could underlie a system of environmental protection. It is intended as one step in the development of a framework for the protection of the environment from the effects of ionizing radiation, and is being published in order to promote awareness of the current developments in this field as well as to encourage discussion amongst those involved

  3. The Ultraviolet Radiation Environment around M dwarf Exoplanet Host Stars

    Science.gov (United States)

    France, Kevin; Froning, Cynthia S.; Linsky, Jeffrey L.; Roberge, Aki; Stocke, John T.; Tian, Feng; Bushinsky, Rachel; Désert, Jean-Michel; Mauas, Pablo; Vieytes, Mariela; Walkowicz, Lucianne M.

    2013-02-01

    The spectral and temporal behavior of exoplanet host stars is a critical input to models of the chemistry and evolution of planetary atmospheres. Ultraviolet photons influence the atmospheric temperature profiles and production of potential biomarkers on Earth-like planets around these stars. At present, little observational or theoretical basis exists for understanding the ultraviolet spectra of M dwarfs, despite their critical importance to predicting and interpreting the spectra of potentially habitable planets as they are obtained in the coming decades. Using observations from the Hubble Space Telescope, we present a study of the UV radiation fields around nearby M dwarf planet hosts that covers both far-UV (FUV) and near-UV (NUV) wavelengths. The combined FUV+NUV spectra are publicly available in machine-readable format. We find that all six exoplanet host stars in our sample (GJ 581, GJ 876, GJ 436, GJ 832, GJ 667C, and GJ 1214) exhibit some level of chromospheric and transition region UV emission. No "UV-quiet" M dwarfs are observed. The bright stellar Lyα emission lines are reconstructed, and we find that the Lyα line fluxes comprise ~37%-75% of the total 1150-3100 Å flux from most M dwarfs; gsim103 times the solar value. We develop an empirical scaling relation between Lyα and Mg II emission, to be used when interstellar H I attenuation precludes the direct observation of Lyα. The intrinsic unreddened flux ratio is F(Lyα)/F(Mg II) = 10 ± 3. The F(FUV)/F(NUV) flux ratio, a driver for abiotic production of the suggested biomarkers O2 and O3, is shown to be ~0.5-3 for all M dwarfs in our sample, >103 times the solar ratio. For the four stars with moderate signal-to-noise Cosmic Origins Spectrograph time-resolved spectra, we find UV emission line variability with amplitudes of 50%-500% on 102-103 s timescales. This effect should be taken into account in future UV transiting planet studies, including searches for O3 on Earth-like planets. Finally, we

  4. Existing condition assessment of radiation environment quality in dwellings

    International Nuclear Information System (INIS)

    Xu Jiaang; Li Fusheng; Chen Yingmin; Zhu Jianguo; Lu Feng; Song Gang

    2008-01-01

    Objective: To assess the radiactivity levels of Jinan dwellings and the indoor environment quality. Methods: Using the self made Measurement Cups of Indoor Environmental Radioactivity Evaluation (MCIERE) (ZL 200620082698.7) to measure the gamma ray dose rate, 222 Rn activity concentration, 220 Rn activity concentration and EECTn. Results: The geometric mean of 222 Rn activity concentrations that showed a clear lognoxmal distribution tendency in 411 rooms of Jinan was 45 Bq ·m -3 , the range which was from 18 to 203 Bq·m -3 . The geometric mean of 220 Rn activity concentration that was also nearly lognormal distribution in 203 rooms of Jinan was 16 Bq·m -3 and the range of the activity coneentratons was from 1 to 167 Bq· m -3 . The geometric mean of EECT, that was nearly lognormal distribution in 204 rooms of Jinan was 1.082 Bq ·m -3 , the range was from 0.015 to 10.230 Bq·m -3 . The arithmetic mean of the gamma ray dose rate that was nearly Gaussian distribution in 412 rooms of Jinan was 0.106 μSv·h -1 , the concentration range from 0.041 to 0.167 μSv·h -1 . Conclusion: The internal irradiation annual effective dose caused by 222 Rn and its progeny, 220 Rn and its progeny and of Jinan inhabitant was 1.189 mSv, the external irradiation annual effective close caused by the gamma ray from the ground and buildings was 0.743 mSv. The mean total annual effective dose was 2.187 mSv and the highest annual effective dose level was above 5 mSv. (authors)

  5. Experimental investigation of the radiation shielding of a MCP detector in the radiation environment near Europa

    Science.gov (United States)

    Tulej, Marek; Wurz, Peter; Meyer, Stefan; Lasi, Davide; Lüthi, Matthias; Galli, André; Piazza, Daniele; Desorgher, Laurent; Hajdas, Wojciech; Reggiani, Davide; Karlsson, Stefan; Kalla, Leif

    2016-04-01

    The Neutral Ion Mass spectrometer (NIM) is one of the six instruments in the Particle Environmental Package (PEP) designed for the JUICE mission of ESA to the Jupiter system. NIM will conduct detailed measurements of chemical composition of Jovian moon exospheres and is equipped with a sensitive MCP ion detector. To maintain high sensitivity of the NIM instrument, background signals arising from the presence of a large background of penetrating radiation (mostly high-energy electrons and protons) in Jupiter's magnetosphere have to be minimised. We investigate the performance of a layered-Z radiation shield, an Al-Ta-Al sandwich, as a potential shielding against high-energy electrons. The experimental investigations were performed at the PiM1 beam line of the High Intensity Proton Accelerator Facilities located at the Paul Scherrer Institute (PSI), Villigen, Switzerland. The facility delivers a particle beam containing e,  and  with an adjustable momentum ranging from 17.5 to 345 MeV/c. The measurements of the induced radiation background generated during the interaction of primary particles with Al-Ta-Al sandwich were conducted by beam diagnostic methods and a MCP detector. Diagnostic methods provided for the characterisation of the beam parameters (beam geometry, flux and intensity) and identification of individual particles in the primary beam and in the flux of secondary particles. The MCP detector measurements provided information on the effects of radiation and the results of these measurements define the performance of the shielding material in reducing the background arising from penetrating radiation. In parallel, we performed modelling studies using GEANT 4 and GRASS methods to identify products of the interaction and predict their fluxes and particle rates at the MCP detector. Combination of the experiment and modelling studies yields detailed characterisation of the radiation effects produced by the interaction of the incident e- in the

  6. Degradation mechanisms of cable insulation materials during radiation-thermal ageing in radiation environment

    Science.gov (United States)

    Seguchi, Tadao; Tamura, Kiyotoshi; Ohshima, Takeshi; Shimada, Akihiko; Kudoh, Hisaaki

    2011-02-01

    Radiation and thermal degradation of ethylene-propylene rubber (EPR) and crosslinked polyethylene (XLPE) as cable insulation materials were investigated by evaluating tensile properties, gel-fraction, and swelling ratio, as well as by the infrared (FTIR) analysis. The activation energy of thermal oxidative degradation changed over the range 100-120 °C for both EPR and XLPE. This may be attributed to the fact that the content of an antioxidant used as the stabilizer for polymers decreases by evaporation during thermal ageing at high temperatures. The analysis of antioxidant content and oxidative products in XLPE as a model sample showed that a small amount of antioxidant significantly reduced the extent of thermal oxidation, but was not effective for radiation induced oxidation. The changes in mechanical properties were well reflected by the degree of oxidation. A new model of polymer degradation mechanisms was proposed where the degradation does not take place by chain reaction via peroxy radical and hydro-peroxide. The role of the antioxidant in the polymer is the reduction of free radical formation in the initiation step in thermal oxidation, and it could not stop radical reactions for either radiation or thermal oxidation.

  7. Degradation mechanisms of cable insulation materials during radiation-thermal ageing in radiation environment

    Energy Technology Data Exchange (ETDEWEB)

    Seguchi, Tadao, E-mail: seguchi@aj.wakwak.co [Japan Atomic Energy Agency, Tokai 319-1195 (Japan); Tamura, Kiyotoshi; Ohshima, Takeshi; Shimada, Akihiko [Japan Atomic Energy Agency, Tokai 319-1195 (Japan); Kudoh, Hisaaki [University of Tokyo, Tokai 319-1195 (Japan)

    2011-02-15

    Radiation and thermal degradation of ethylene-propylene rubber (EPR) and crosslinked polyethylene (XLPE) as cable insulation materials were investigated by evaluating tensile properties, gel-fraction, and swelling ratio, as well as by the infrared (FTIR) analysis. The activation energy of thermal oxidative degradation changed over the range 100-120 {sup o}C for both EPR and XLPE. This may be attributed to the fact that the content of an antioxidant used as the stabilizer for polymers decreases by evaporation during thermal ageing at high temperatures. The analysis of antioxidant content and oxidative products in XLPE as a model sample showed that a small amount of antioxidant significantly reduced the extent of thermal oxidation, but was not effective for radiation induced oxidation. The changes in mechanical properties were well reflected by the degree of oxidation. A new model of polymer degradation mechanisms was proposed where the degradation does not take place by chain reaction via peroxy radical and hydro-peroxide. The role of the antioxidant in the polymer is the reduction of free radical formation in the initiation step in thermal oxidation, and it could not stop radical reactions for either radiation or thermal oxidation.

  8. Radiation effects on man health, environment, safety, security. Global Chernobyl mapping

    International Nuclear Information System (INIS)

    Bebeshko, V.; Bazyka, D.; Volovik, S.; Loganovsky, K.; Sushko, V.; Siedow, J.; Cohen, H.; Ginsburg, G.; Chao, N.; Chute, J.

    2007-01-01

    Complete text of publication follows. Objectives: Ionizing radiation is a primordial terrestrial and extraterrestrial background and archetypal environmental stress-factor for life origin, evolution, and existence. We all live in radiation world inevitably involving nuclear energy production, nuclear weapon, nuclear navy, radioactive waste, pertinent medical diagnostics and treatment, etc with connected certain probability of relevant accidents and terrorist attack, space and jet travels, high natural background radiation, etc - actual and potential sources of radiation exposures and effects. State-of- the art integral fundamental research on radiation effects on man health, environment, safety, and security (REMHESS) is nowadays paramount necessity and challenge. Methods and results: In given generalized conceptual framework unique 20 years Chernobyl multidimensional research and databases for radiation effects on man's all organism systems represent invaluable original basis and resources for mapping Chernobyl data and REMHESS challenge. Granted by DOE brand new Chernobyl Research and Service Project based on 'Sarcophagus-II' (Object 'Shelter') workers only one in radiation history baseline cohort, corresponding biorepository prospective dynamic data, integrated conceptual database system, and 'state of the art' 'omics' (genomics, proteomics, metabolomics) analysis is designed specifically for coherent addressing global REMHESS problems. In this connection 'Sarcophagus-II' is only one unique universal model. Conclusions: The fundamental goals of novel strategic Project and global Chernobyl mapping are to determine specific 'omics' signatures of radiation for man depending of exposure peculiarity to understand ultimate molecular mechanisms of radiation effects, gene environment interactions, etiology of organisms systems disorders and diseases, and to develop new biomarkers and countermeasures to protect man health in the framework of global REMHESS challenge

  9. Experimental Characterization of a Composite Morphing Radiator Prototype in a Relevant Thermal Environment

    Science.gov (United States)

    Bertagne, Christopher L.; Chong, Jorge B.; Whitcomb, John D.; Hartl, Darren J.; Erickson, Lisa R.

    2017-01-01

    For future long duration space missions, crewed vehicles will require advanced thermal control systems to maintain a desired internal environment temperature in spite of a large range of internal and external heat loads. Current radiators are only able to achieve turndown ratios (i.e. the ratio between the radiator's maximum and minimum heat rejection rates) of approximately 3:1. Upcoming missions will require radiators capable of 12:1 turndown ratios. A radiator with the ability to alter shape could significantly increase turndown capacity. Shape memory alloys (SMAs) offer promising qualities for this endeavor, namely their temperature-dependent phase change and capacity for work. In 2015, the first ever morphing radiator prototype was constructed in which SMA actuators passively altered the radiator shape in response to a thermal load. This work describes a follow-on endeavor to demonstrate a similar concept using highly thermally conductive composite materials. Numerous versions of this new concept were tested in a thermal vacuum environment and successfully demonstrated morphing behavior and variable heat rejection, achieving a turndown ratio of 4.84:1. A summary of these thermal experiments and their results are provided herein.

  10. The Martian surface radiation environment – a comparison of models and MSL/RAD measurements

    Directory of Open Access Journals (Sweden)

    Matthiä Daniel

    2016-01-01

    Full Text Available Context: The Radiation Assessment Detector (RAD on the Mars Science Laboratory (MSL has been measuring the radiation environment on the surface of Mars since August 6th 2012. MSL-RAD is the first instrument to provide detailed information about charged and neutral particle spectra and dose rates on the Martian surface, and one of the primary objectives of the RAD investigation is to help improve and validate current radiation transport models. Aims: Applying different numerical transport models with boundary conditions derived from the MSL-RAD environment the goal of this work was to both provide predictions for the particle spectra and the radiation exposure on the Martian surface complementing the RAD sensitive range and, at the same time, validate the results with the experimental data, where applicable. Such validated models can be used to predict dose rates for future manned missions as well as for performing shield optimization studies. Methods: Several particle transport models (GEANT4, PHITS, HZETRN/OLTARIS were used to predict the particle flux and the corresponding radiation environment caused by galactic cosmic radiation on Mars. From the calculated particle spectra the dose rates on the surface are estimated. Results: Calculations of particle spectra and dose rates induced by galactic cosmic radiation on the Martian surface are presented. Although good agreement is found in many cases for the different transport codes, GEANT4, PHITS, and HZETRN/OLTARIS, some models still show large, sometimes order of magnitude discrepancies in certain particle spectra. We have found that RAD data is helping to make better choices of input parameters and physical models. Elements of these validated models can be applied to more detailed studies on how the radiation environment is influenced by solar modulation, Martian atmosphere and soil, and changes due to the Martian seasonal pressure cycle. By extending the range of the calculated particle

  11. The retention characteristics of nonvolatile SNOS memory transistors in a radiation environment: Experiment and model

    International Nuclear Information System (INIS)

    McWhorter, P.J.; Miller, S.L.; Dellin, T.A.; Axness, C.L.

    1987-01-01

    Experimental data and a model to accurately and quantitatively predict the data are presented for retention of SNOS memory devices over a wide range of dose rates. A wide range of SNOS stack geometries are examined. The model is designed to aid in screening nonvolatile memories for use in a radiation environment

  12. International symposium on radiation technology for conservation of the environment. Extended synopses

    International Nuclear Information System (INIS)

    1997-09-01

    This document includes extended synopses of 54 presentations given at the International Symposium on Radiation Technology for the conservation of the Environment held in Zakopane near Cracow), Poland, 8-12 September 1997. Each presentation is separately indexed. Refs, figs, tabs

  13. Adaptive response in frogs chronically exposed to low doses of ionizing radiation in the environment

    International Nuclear Information System (INIS)

    Audette-Stuart, M.; Kim, S.B.; McMullin, D.; Festarini, A.; Yankovich, T.L.; Carr, J.; Mulpuru, S.

    2011-01-01

    Using the micronucleus assay, decreased levels of DNA damage were found after high dose ionizing radiation exposure of liver cells taken from frogs inhabiting a natural environment with above-background levels of ionizing radiation, compared to cells taken from frogs inhabiting background areas. The data obtained from a small number of animals suggest that stress present in the above-background environment could induce an adaptive response to ionizing radiation. This study did not reveal harmful effects of exposure to low levels of radioactivity. On the contrary, stress present in the above-background area may serve to enhance cellular defense mechanisms. - Highlights: → Frogs were collected from background and higher tritium level habitats. → The micronucleus assay was conducted on liver cells obtained from the frogs. → No detrimental effects were noted in frogs exposed to elevated tritium. → Adaptive responses were observed in frogs exposed to elevated tritium.

  14. Adaptive response in frogs chronically exposed to low doses of ionizing radiation in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Audette-Stuart, M., E-mail: stuartm@aecl.ca [Environmental Technologies Branch, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario, K0J 1P0 (Canada); Kim, S.B.; McMullin, D.; Festarini, A.; Yankovich, T.L.; Carr, J.; Mulpuru, S. [Environmental Technologies Branch, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario, K0J 1P0 (Canada)

    2011-06-15

    Using the micronucleus assay, decreased levels of DNA damage were found after high dose ionizing radiation exposure of liver cells taken from frogs inhabiting a natural environment with above-background levels of ionizing radiation, compared to cells taken from frogs inhabiting background areas. The data obtained from a small number of animals suggest that stress present in the above-background environment could induce an adaptive response to ionizing radiation. This study did not reveal harmful effects of exposure to low levels of radioactivity. On the contrary, stress present in the above-background area may serve to enhance cellular defense mechanisms. - Highlights: > Frogs were collected from background and higher tritium level habitats. > The micronucleus assay was conducted on liver cells obtained from the frogs. > No detrimental effects were noted in frogs exposed to elevated tritium. > Adaptive responses were observed in frogs exposed to elevated tritium.

  15. Terrain and Radiation Mapping in Post-Disaster Environments Using an Autonomous Helicopter

    Directory of Open Access Journals (Sweden)

    Kevin Kochersberger

    2012-07-01

    Full Text Available Recent events have highlighted the need for unmanned remote sensing in dangerous areas, particularly where structures have collapsed or explosions have occurred, to limit hazards to first responders and increase their efficiency in planning response operations. In the case of the Fukushima nuclear reactor explosion, an unmanned helicopter capable of obtaining overhead images, gathering radiation measurements, and mapping both the structural and radiation content of the environment would have given the response team invaluable data early in the disaster, thereby allowing them to understand the extent of the damage and areas where dangers to personnel existed. With this motivation, the Unmanned Systems Lab at Virginia Tech has developed a remote sensing system for radiation detection and aerial imaging using a 90 kg autonomous helicopter and sensing payloads for the radiation detection and imaging operations. The radiation payload, which is the sensor of focus in this paper, consists of a scintillating type detector with associated software and novel search algorithms to rapidly and effectively map and locate sources of high radiation intensity. By incorporating this sensing technology into an unmanned aerial vehicle system, crucial situational awareness can be gathered about a post-disaster environment and response efforts can be expedited. This paper details the radiation mapping and localization capabilities of this system as well as the testing of the various search algorithms using simulated radiation data. The various components of the system have been flight tested over a several-year period and a new production flight platform has been built to enhance reliability and maintainability. The new system is based on the Aeroscout B1-100 helicopter platform, which has a one-hour flight endurance and uses a COFDM radio system that gives the helicopter an effective range of 7 km.

  16. Effects of chronic exposure to acidic environment on the response of tumor cells to radiation.

    Science.gov (United States)

    Kim, So-Ra; Kim, Eun-Hee

    2016-09-01

    The influence of short-term exposure to an acidic environment on the radiosensitivity of tumor cells has been extensively explored, but the implication of chronic exposure to an acidic environment for the response of tumor cells to radiation has not been fully elucidated. This study aimed to investigate the effects of chronic pre- and post-irradiation exposure of tumor cells to an acidic environment on the radiation-induced clonogenic death. Rat gliosarcoma cells were used throughout the in vitro study. Cells were exposed to pH 6.6 medium for varying durations of up to 4 days before and after X-irradiation. Cell viability, apoptosis, clonogenic cell death and cell cycle distribution were observed. Incubation of tumor cells in pH 6.6 medium for 2 or 4 days extended cell cycle, decreased cell viability, and induced apoptotic and clonogenic cell death. The radiation-induced clonogenic death was increased by 2- or 4-day pre-irradiation exposure of tumor cells to pH 6.6 medium, whereas it was reduced by 4-day post-irradiation exposure to an acidic medium. Prolonged exposure to an acidic environment enhanced the sensitivity of tumor cells to subsequent X-irradiation. However, the radiosensitization by pre-irradiation exposure was almost completely nullified by prolonged post-irradiation exposure to an acidic environment.

  17. The Martian and extraterrestrial UV radiation environment--1. Biological and closed-loop ecosystem considerations.

    Science.gov (United States)

    Cockell, C S; Andrady, A L

    1999-01-01

    The Martian surface is exposed to both UVC radiation (life support systems that use ambient sunlight, must address this problem. Here we examine the UV radiation environment of Mars with respect to biological systems. Action spectra and UV surface fluxes are used to estimate the UV stress that both DNA and chloroplasts would experience. From this vantage point it is possible to consider appropriate measures to address the problem of the Martian UV environment for future long term human exploration and settlement strategies. Some prospects for improving the UV tolerance of organisms are also discussed. Existing artificial ecosystems such as Biosphere 2 can provide some insights into design strategies pertinent to high UV environments. Some prospects for improving the UV tolerance of organisms are also discussed. The data also have implications for the establishment of closed-loop ecosystems using natural sunlight on the lunar surface and elsewhere in the Solar System.

  18. Leo Tolstoy's theory of sleep.

    Science.gov (United States)

    Vein, Alla A

    2008-03-01

    Throughout his life, Leo Tolstoy was fascinated by the phenomena of sleep and dreams. He composed a series of observations and judgements that were brought together under "my theory of sleep". Tolstoy was constantly preoccupied with the basic principles of "the theory". It is hard to name a work by him where a description of sleep and/or a dream does not play a vital role in the unfolding of the plot. They testify to Tolstoy's interest in the mechanism of sleep and in the processes of falling asleep and waking up. Tolstoy viewed sleep as a specific state of consciousness, and he subsequently linked the concept of sleep with the concept of death. For him sleep and awakening were experiences emblematic of life and death.

  19. International conference on the protection of the environment from the effects of ionizing radiation. Contributed papers

    International Nuclear Information System (INIS)

    2003-01-01

    An International Conference on the Protection of the Environment from the Effects of Ionizing Radiation, organized by the International Atomic Energy Agency (IAEA) in co-operation with the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), the European Commission (EC) and the International Union of Radioecology (IUR), will be held in Stockholm, Sweden, from 6-10 October 2003. This Conference will be hosted by the Government of Sweden through the Swedish Radiation Protection Authority (SSI). This publication contains contributed papers submitted on issues within the scope of the conference, which were accepted following a review by the Conference Programme Committee. The primary objective of this Conference is to foster information exchange, with the aim of promoting the development of a coherent international policy on the protection of the environment from effects attributable to ionizing radiation. This Conference is one in a series of meetings organized by, or held in co-operation with, the IAEA on this subject. It will include a review of recent developments in this area, and consideration of their implications for future work at national and international levels. The topics on which contributed papers were requested are as follows: Existing environmental protection approaches; Development of an international assessment framework; The scientific basis for environmental radiation assessment; Development of management approaches

  20. Methodology for Estimating Radiation Dose Rates to Freshwater Biota Exposed to Radionuclides in the Environment

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, B.G.

    1993-01-01

    The purpose of this report is to present a methodology for evaluating the potential for aquatic biota to incur effects from exposure to chronic low-level radiation in the environment. Aquatic organisms inhabiting an environment contaminated with radioactivity receive external radiation from radionuclides in water, sediment, and from other biota such as vegetation. Aquatic organisms receive internal radiation from radionuclides ingested via food and water and, in some cases, from radionuclides absorbed through the skin and respiratory organs. Dose rate equations, which have been developed previously, are presented for estimating the radiation dose rate to representative aquatic organisms from alpha, beta, and gamma irradiation from external and internal sources. Tables containing parameter values for calculating radiation doses from selected alpha, beta, and gamma emitters are presented in the appendix to facilitate dose rate calculations. The risk of detrimental effects to aquatic biota from radiation exposure is evaluated by comparing the calculated radiation dose rate to biota to the U.S. Department of Energy's (DOE's) recommended dose rate limit of 0.4 mGy h{sup -1} (1 rad d{sup -1}). A dose rate no greater than 0.4 mGy h{sup -1} to the most sensitive organisms should ensure the protection of populations of aquatic organisms. DOE's recommended dose rate is based on a number of published reviews on the effects of radiation on aquatic organisms that are summarized in the National Council on Radiation Protection and Measurements Report No. 109 (NCRP 1991). The literature identifies the developing eggs and young of some species of teleost fish as the most radiosensitive organisms. DOE recommends that if the results of radiological models or dosimetric measurements indicate that a radiation dose rate of 0.1 mGy h{sup -1} will be exceeded, then a more detailed evaluation of the potential ecological consequences of radiation exposure to endemic

  1. Solar Arrays for Low-Irradiance Low-Temperature and High-Radiation Environments

    Science.gov (United States)

    Boca, Andreea (Principal Investigator); Stella, Paul; Kerestes, Christopher; Sharps, Paul

    2017-01-01

    This is the Base Period final report DRAFT for the JPL task 'Solar Arrays for Low-Irradiance Low-Temperature and High-Radiation Environments', under Task Plan 77-16518 TA # 21, for NASA's Extreme Environments Solar Power (EESP) project. This report covers the Base period of performance, 7/18/2016 through 5/2/2017.The goal of this project is to develop an ultra-high efficiency lightweight scalable solar array technology for low irradiance, low temperature and high-radiation (LILT/Rad) environments. The benefit this technology will bring to flight systems is a greater than 20 reduction in solar array surface area, and a six-fold reduction in solar array mass and volume. The EESP project objectives are summarized in the 'NRA Goal' column of Table 1. Throughout this report, low irradiance low temperature (LILT) refers to 5AU -125 C test conditions; beginning of life (BOL) refers to the cell state prior to radiation exposure; and end of life (EOL) refers to the test article condition after exposure to a radiation dose of 4e15 1MeV e(-)/cm(exp 2).

  2. Radiation technology for conservation of the environment. Proceedings of a symposium

    International Nuclear Information System (INIS)

    1998-06-01

    In September 1997 the IAEA held an International Symposium in Zakopane, Poland, on the applications of radiation technology in conservation of environment. The symposium attended 110 participants representing 38 Member States. The objective was to review the status of current developments and applications of radiation processing in the control of environment pollution and to discuss future developments. The scientific programme covered a wide range of different applications of radiation technology, such as purification of exhaust gases, decontamination of wastewater from industrial and municipal sources, sewage sludge treatment, disinfection and detoxication of solid waste, recycling and the treatment of plastic and solid waste. The document contains full presentations. The symposium (56 papers) was held in 10 sessions as follows: Purification of Exhaust Gases (8 papers); Radiation Chemistry and the Environment (5 papers); Purification and Decontamination of Water (10 papers); Sewage Sludge Treatment (6 papers); Biomedical Applications (5 papers); Recycling and Treatment of Plastic and Solid Wastes (4 papers); Facilities (4 papers); Quality Assurance, Quality Control (4 papers); Transfer of Technology through Technical Co-Operation (5 papers); Curing, Cross-Linking and Grafting (5 papers). A separate abstract and indexing were provided for each paper

  3. Assessing the effects of ultraviolet radiation on the photosynthetic potential in Archean marine environments

    Science.gov (United States)

    Avila-Alonso, Dailé; Baetens, Jan M.; Cardenas, Rolando; de Baets, Bernard

    2017-07-01

    In this work, the photosynthesis model presented by Avila et al. in 2013 is extended and more scenarios inhabited by ancient cyanobacteria are investigated to quantify the effects of ultraviolet (UV) radiation on their photosynthetic potential in marine environments of the Archean eon. We consider ferrous ions as blockers of UV during the Early Archean, while the absorption spectrum of chlorophyll a is used to quantify the fraction of photosynthetically active radiation absorbed by photosynthetic organisms. UV could have induced photoinhibition at the water surface, thereby strongly affecting the species with low light use efficiency. A higher photosynthetic potential in early marine environments was shown than in the Late Archean as a consequence of the attenuation of UVC and UVB by iron ions, which probably played an important role in the protection of ancient free-floating bacteria from high-intensity UV radiation. Photosynthetic organisms in Archean coastal and ocean environments were probably abundant in the first 5 and 25 m of the water column, respectively. However, species with a relatively high efficiency in the use of light could have inhabited ocean waters up to a depth of 200 m and show a Deep Chlorophyll Maximum near 60 m depth. We show that the electromagnetic radiation from the Sun, both UV and visible light, could have determined the vertical distribution of Archean marine photosynthetic organisms.

  4. Use of micronucleus test in the assessment of radiation effects in aquatic environments

    International Nuclear Information System (INIS)

    Araujo, Edvaldo F. de; Silva, Luanna R.S.; Lima, Pedro A. de S.; Amancio, Francisco F.; Melo, Ana Maria M. de A.; Silva, Edvane B. da; Silva, Ronaldo C. da

    2011-01-01

    The study of the effects of radioactive substances on the environment is accomplished by radioecology. This science has played an important role in combating all forms of pollution. The uncontrolled use of physical and chemical agents has been a concern for environmental regulatory agencies, due to the serious damage to ecosystems. Aquatic organisms are exposed to a variety of pollutants harmful to aquatic systems. The mollusks Biomphalaria glabrata has been featured as a bioindicator to possess characteristics such as short reproductive cycle ease of maintenance in the laboratory and low maintenance cost. The micronucleus assay has been shown to be a great test to identify mutagenic effects caused by physical and chemical agents. In this study the frequency of micronuclei in haemocytes of Biomphalaria glabrata exposed to high doses of 60 Co gamma radiation contributing to a further standardization of this test as an indicator of the presence of radioactive contamination in aquatic environments. The young adult snails of Biomphalaria glabrata were divided into groups and subjected to a dose of 0 (control), 40 and 60 Gy of gamma radiation. The results showed that snails irradiated with 40 Gy showed a smaller number of haemocytes, whereas those exposed to 60 Gy had a greater quantity of these cells compared to control group. It can be concluded that the morphological analysis and the frequency of micronuclei in haemocytes of Biomphalaria glabrata exposed to 60 Co gamma radiation may be used in studies of the action of high doses of radiation in aquatic environments (author)

  5. Radiation Environment in EARTH-MOON Space: Results from Radom Experiment Onboard CHANDRAYAAN-1

    Science.gov (United States)

    Vadawale, S. V.; Goswami, J. N.; Dachev, T. P.; Tomov, B. T.; Girish, V.

    2011-07-01

    The radiation monitor (RADOM) payload is a miniature dosimeter spectrometer onboard Chandrayaan-1 mission for monitoring the local radiation environment in near-Earth space and in lunar space. RADOM measured the total absorbed dose and spectrum of the deposited energy from high-energy particles in near-Earth space, en-route and in lunar orbit. RADOM was the first experiment to be switched on soon after the launch of Chandrayaan-1 and was operational till the end of the mission. This article summarizes the observations carried out by RADOM during the entire life time of the Chandrayaan-1 mission and some of the salient results.

  6. A three-dimensional radiative transfer model for shallow water environments.

    Science.gov (United States)

    Hedley, John

    2008-12-22

    A geometric optical model for three-dimensional radiative transfer capable of handling arbitrary arrangements of surfaces within anisotropic scattering media is described. The model operates by discretizing surfaces and volumes into patches and voxels and establishing the radiative transfer relationship between every pair of elements. In a plane-parallel configuration results for directional radiance agree closely with the numerical integration invariant imbedded method. Model accuracy for two examples incorporating surface water waves and complex benthic structures were assessed by conservation of energy, errors were less than 1%. Potential applications in remote sensing or photobiological studies of structurally complex benthos in shallow water environments are illustrated.

  7. Radiation-induced apoptosis in different pH environments in vitro

    International Nuclear Information System (INIS)

    Lee, Hyung-Sik; Park, Heon J.; Lyons, John C.; Griffin, Robert J.; Auger, Elizabeth A.; Song, Chang W.

    1997-01-01

    Purpose: The effect of environmental pH on the radiation-induced apoptosis in tumor cells in vitro was investigated. Methods and Materials: Mammary adenocarcinoma cells of A/J mice (SCK cells) were irradiated with γ-rays using a 137 Cs irradiator and incubated in media of different pHs. After incubation at 37 deg. C for 24-120 h the extent of apoptosis was determined using agarose gel electrophoresis, TdT-mediated dUTP-biotin nick end labeling (TUNEL) staining, flow cytometry, and release of 3 H from 3 H-thymidine labeled cells. The clonogenicity of the cells irradiated in different pH medium was determined, and the progression of cells through the cell cycle after irradiation in different pHs was also determined with flow cytometry. Results: Irradiation with 2-12 Gy of γ-rays induced apoptosis in SCK cells in pH 7.5 medium within 48 h as judged from the results of four different assays mentioned. Radiation-induced apoptosis declined as the medium pH was lowered from 7.5 to 6.4. Specifically, the radiation-induced degradation of DNA including the early DNA breaks, as determined with the TUNEL method, progressively declined as the medium pH was lowered so that little DNA fragmentation occurred 48 h after irradiation with 12 Gy in pH 6.6 medium. When the cells were irradiated and incubated for 48 h in pH 6.6 medium and the medium was replaced with pH 7.5 medium, DNA fragmentation promptly occurred. DNA fragmentation also occurred even in pH 6.6 medium when the cells were irradiated and maintained in pH 7.5 medium for 8 h or longer post-irradiation before incubation in pH 6.6 medium. The radiation-induced G 2 arrest in pH 6.6 medium lasted markedly longer than that in pH 7.5 medium. Conclusion: Radiation-induced apoptosis in SCK cells in vitro is reversibly suppressed in an acidic environment. Taking the results of four different assays together, it was concluded that early step(s) in the apoptotic pathway, probably the DNA break or upstream of DNA break, is

  8. DOSIS & DOSIS 3D: radiation measurements with the DOSTEL instruments onboard the Columbus Laboratory of the ISS in the years 2009–2016

    Directory of Open Access Journals (Sweden)

    Berger Thomas

    2017-01-01

    Full Text Available The natural radiation environment in Low Earth Orbit (LEO differs significantly in composition and energy from that found on Earth. The space radiation field consists of high energetic protons and heavier ions from Galactic Cosmic Radiation (GCR, as well as of protons and electrons trapped in the Earth’s radiation belts (Van Allen belts. Protons and some heavier particles ejected in occasional Solar Particle Events (SPEs might in addition contribute to the radiation exposure in LEO. All sources of radiation are modulated by the solar cycle. During solar maximum conditions SPEs occur more frequently with higher particle intensities. Since the radiation exposure in LEO exceeds exposure limits for radiation workers on Earth, the radiation exposure in space has been recognized as a main health concern for humans in space missions from the beginning of the space age on. Monitoring of the radiation environment is therefore an inevitable task in human spaceflight. Since mission profiles are always different and each spacecraft provides different shielding distributions, modifying the radiation environment measurements needs to be done for each mission. The experiments “Dose Distribution within the ISS (DOSIS” (2009–2011 and “Dose Distribution within the ISS 3D (DOSIS 3D” (2012–onwards onboard the Columbus Laboratory of the International Space Station (ISS use a detector suite consisting of two silicon detector telescopes (DOSimetry TELescope = DOSTEL and passive radiation detector packages (PDP and are designed for the determination of the temporal and spatial variation of the radiation environment. With the DOSTEL instruments’ changes of the radiation composition and the related exposure levels in dependence of the solar cycle, the altitude of the ISS and the influence of attitude changes of the ISS during Space Shuttle dockings inside the Columbus Laboratory have been monitored. The absorbed doses measured at the end of May 2016

  9. DOSIS & DOSIS 3D: radiation measurements with the DOSTEL instruments onboard the Columbus Laboratory of the ISS in the years 2009-2016

    Science.gov (United States)

    Berger, Thomas; Burmeister, Sönke; Matthiä, Daniel; Przybyla, Bartos; Reitz, Günther; Bilski, Pawel; Hajek, Michael; Sihver, Lembit; Szabo, Julianna; Ambrozova, Iva; Vanhavere, Filip; Gaza, Ramona; Semones, Edward; Yukihara, Eduardo G.; Benton, Eric R.; Uchihori, Yukio; Kodaira, Satoshi; Kitamura, Hisashi; Boehme, Matthias

    2017-03-01

    The natural radiation environment in Low Earth Orbit (LEO) differs significantly in composition and energy from that found on Earth. The space radiation field consists of high energetic protons and heavier ions from Galactic Cosmic Radiation (GCR), as well as of protons and electrons trapped in the Earth's radiation belts (Van Allen belts). Protons and some heavier particles ejected in occasional Solar Particle Events (SPEs) might in addition contribute to the radiation exposure in LEO. All sources of radiation are modulated by the solar cycle. During solar maximum conditions SPEs occur more frequently with higher particle intensities. Since the radiation exposure in LEO exceeds exposure limits for radiation workers on Earth, the radiation exposure in space has been recognized as a main health concern for humans in space missions from the beginning of the space age on. Monitoring of the radiation environment is therefore an inevitable task in human spaceflight. Since mission profiles are always different and each spacecraft provides different shielding distributions, modifying the radiation environment measurements needs to be done for each mission. The experiments "Dose Distribution within the ISS (DOSIS)" (2009-2011) and "Dose Distribution within the ISS 3D (DOSIS 3D)" (2012-onwards) onboard the Columbus Laboratory of the International Space Station (ISS) use a detector suite consisting of two silicon detector telescopes (DOSimetry TELescope = DOSTEL) and passive radiation detector packages (PDP) and are designed for the determination of the temporal and spatial variation of the radiation environment. With the DOSTEL instruments' changes of the radiation composition and the related exposure levels in dependence of the solar cycle, the altitude of the ISS and the influence of attitude changes of the ISS during Space Shuttle dockings inside the Columbus Laboratory have been monitored. The absorbed doses measured at the end of May 2016 reached up to 286

  10. Modern state of the application of ionizing radiation for protection of environment. 1. Ionizing radiation sources. Purification of natural and drinking water (review)

    International Nuclear Information System (INIS)

    Pikaev, AK.

    2000-01-01

    Review of modern state of the application of ionizing radiations for protection of environment and natural and drinking water purification is presented. Building of installations with electron accelerators with summarized power of beam ∼0.6 MW signifies that application of ionizing radiation for ecological needs increase. It is pointed out that extensible application of electron accelerators is explained by their safety and efficiency as compared with gamma-sources. New information about ionizing radiation sources, radiation-chemical purification of polluted natural and drinking water, mechanisms of processes taking place during treatment by ionizing radiations are generalized [ru

  11. CONSTRAINING THE RADIATION AND PLASMA ENVIRONMENT OF THE KEPLER CIRCUMBINARY HABITABLE-ZONE PLANETS

    Energy Technology Data Exchange (ETDEWEB)

    Zuluaga, Jorge I. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Mason, Paul A. [New Mexico State University—DACC, Las Cruces, NM 88003 (United States); Cuartas-Restrepo, Pablo A. [FACom—Instituto de Física—FCEN, Universidad de Antioquia, Calle 70 No. 52-21, Medellín (Colombia)

    2016-02-20

    The discovery of many planets using the Kepler telescope includes 10 planets orbiting eight binary stars. Three binaries, Kepler-16, Kepler-47, and Kepler-453, have at least one planet in the circumbinary habitable zone (BHZ). We constrain the level of high-energy radiation and the plasma environment in the BHZ of these systems. With this aim, BHZ limits in these Kepler binaries are calculated as a function of time, and the habitability lifetimes are estimated for hypothetical terrestrial planets and/or moons within the BHZ. With the time-dependent BHZ limits established, a self-consistent model is developed describing the evolution of stellar activity and radiation properties as proxies for stellar aggression toward planetary atmospheres. Modeling binary stellar rotation evolution, including the effect of tidal interaction between stars in binaries, is key to establishing the environment around these systems. We find that Kepler-16 and its binary analogs provide a plasma environment favorable for the survival of atmospheres of putative Mars-sized planets and exomoons. Tides have modified the rotation of the stars in Kepler-47, making its radiation environment less harsh in comparison to the solar system. This is a good example of the mechanism first proposed by Mason et al. Kepler-453 has an environment similar to that of the solar system with slightly better than Earth radiation conditions at the inner edge of the BHZ. These results can be reproduced and even reparameterized as stellar evolution and binary tidal models progress, using our online tool http://bhmcalc.net.

  12. Meie poliitikute seitse viga / Leo Kunnas

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2008-01-01

    Artikkel põhineb reservkolonelleitnant Leo Kunnase mõttepäeval "Isemõtlejad iseolemisest" peetud ettekandel, kus ta toob välja 1930-ndatele aastatele ja tänapäevale iseloomulikud poliitkute eksimused

  13. Eestikeelseid filosoofiaraamatuid oodates / Leo Luks, Margus Ott

    Index Scriptorium Estoniae

    Luks, Leo, 1976-

    2016-01-01

    Möödunud aastal ilmus kaks algupärast eestikeelset filosoofiamonograafiat - Margus Oti "Vägi" ja Leo Luksi "Nihilism ja kirjandus". Nende autorid arutlevad vestluses, miks on filosoofiaraamatuid nii vähe

  14. The Star Formation History of Leo P

    Science.gov (United States)

    McQuinn, Kristen

    2013-10-01

    The nearby {D = 1.7+/-0.3 Mpc}, very low luminosity {M_V = -9.3+/-0.4mag}, gas-rich star forming galaxy Leo P was discovered by its HI 21cm emission in the Arecibo ALFALFA survey. Follow-up optical spectroscopy of its single HII region revealed an oxygen abundance of 12+log{O/H}=7.16+/-0.04, making it the lowest metallicity star forming galaxy in the Local Volume {D history with reasonable time resolution.The star formation history will answer two vital questions: {1} Did Leo P experience suppressed star formation during its early evolution like another isolated dwarf galaxy Leo A? and {2} What fraction of all newly created metals has Leo P been able to retain during its lifetime?

  15. Alfalfa discovery of the nearby gas-rich dwarf galaxy Leo P. IV. Distance measurement from LBT optical imaging

    Energy Technology Data Exchange (ETDEWEB)

    McQuinn, Kristen B. W.; Skillman, Evan D.; Berg, Danielle [Minnesota Institute for Astrophysics, School of Physics and Astronomy, 116 Church Street, S.E., University of Minnesota, Minneapolis, MN 55455 (United States); Cannon, John M. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Salzer, John J.; Rhode, Katherine L. [Department of Astronomy, Indiana University, 727 East 3rd Street, Bloomington, IN 47405 (United States); Adams, Elizabeth A. K.; Giovanelli, Riccardo; Haynes, Martha P. [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Dolphin, Andrew, E-mail: kmcquinn@astro.umn.edu, E-mail: skillman@astro.umn.edu, E-mail: berg@astro.umn.edu, E-mail: jcannon@macalester.edu, E-mail: rhode@astro.indiana.edu, E-mail: slaz@astro.indiana.edu, E-mail: betsey@astro.cornell.edu, E-mail: riccardo@astro.cornell.edu, E-mail: haynes@astro.cornell.edu [Raytheon Company, 1151 E. Hermans Road, Tucson, AZ 85756 (United States)

    2013-12-01

    Leo P is a low-luminosity dwarf galaxy discovered through the blind H I Arecibo Legacy Fast ALFA survey. The H I and follow-up optical observations have shown that Leo P is a gas-rich dwarf galaxy with both active star formation and an underlying older population, as well as an extremely low oxygen abundance. Here, we measure the distance to Leo P by applying the tip of the red giant branch (TRGB) distance method to photometry of the resolved stellar population from new Large Binocular Telescope V and I band imaging. We measure a distance modulus of 26.19{sub −0.50}{sup +0.17} mag corresponding to a distance of 1.72{sub −0.40}{sup +0.14} Mpc. Although our photometry reaches 3 mag below the TRGB, the sparseness of the red giant branch yields higher uncertainties on the lower limit of the distance. Leo P is outside the Local Group with a distance and velocity consistent with the local Hubble flow. While located in a very low-density environment, Leo P lies within ∼0.5 Mpc of a loose association of dwarf galaxies which include NGC 3109, Antlia, Sextans A, and Sextans B, and 1.1 Mpc away from its next nearest neighbor, Leo A. Leo P is one of the lowest metallicity star-forming galaxies known in the nearby universe, comparable in metallicity to I Zw 18 and DDO 68, but with stellar characteristics similar to dwarf spheriodals (dSphs) in the Local Volume such as Carina, Sextans, and Leo II. Given its physical properties and isolation, Leo P may provide an evolutionary link between gas-rich dwarf irregular galaxies and dSphs that have fallen into a Local Group environment and been stripped of their gas.

  16. Cancer and non-cancer risk at low doses of radiation: biological basis of radiation-environment interplay

    International Nuclear Information System (INIS)

    Sasaki, Masao S.

    2013-01-01

    Cancer and non-cancer risk at low doses of ionizing radiation remains poorly defined due to ambiguity at low doses caused by limitations in statistical power and information available on interplay with environment. To deal with these problems, a novel non-parametric statistics was developed based on artificial neural networks theorem and applied to cancer and non-cancer risk in A-bomb survivors. The analysis revealed several unique features at low doses that could not be accounted for by nominal radiation dose alone. They include (1) threshold that varies with organ, gender and age, including cardiovascular diseases, (2) prevalence of infectious diseases, and (3) suppression of pathogenesis of HTLV1. The threshold is unique as it is manifested as negative excess relative risk, a reduction of spontaneous rate at low doses. The response is consistent with currently emerging laboratory data on DNA double-strand break (DSB) repair pathway choice and its sustainability as epigenetic memory in accordance with histone code theory. In response to DSB, of radiation or DNA replication arrest origin, distinct and competitively operating repair pathways are instigated. Activation by low doses of restitution-directed canonical non-homologous end-joining (C-NHEJ) suppresses both error-prone alternative end-joining (Alt-NHEJ) and homologous recombination (HR). The latter two present major pathways to mutagenesis at stalled replication folk associated with endogenous and exogenous genotoxin such as tobacco smoke metabolites and AID-associated somatic hypermutation and class switch recombination in Ig gene. Suppression of these error-prone pathways by low doses of low LET radiation is consistent with the reduction of cancer occurrence by environmental genotoxin, immunodiversity and stable integration of retrovirus DNA, providing a significant modulator of dose linearity at low doses. Whole picture may bring about a new landscape of cancer and non-cancer molecular epidemiology which

  17. An overview of RADOM results for earth and moon radiation environment on Chandrayaan-1 satellite

    Science.gov (United States)

    Dachev, T. P.; Tomov, B. T.; Matviichuk, Yu. N.; Dimitrov, P. S.; Vadawale, S. V.; Goswami, J. N.; De Angelis, G.; Girish, V.

    2011-09-01

    The RADiatiOn Monitor (RADOM) is a miniature dosimeter-spectrometer that flew onboard the Chandrayaan-1 lunar mission in order to monitor the local radiation environment. Primary objective of the RADOM experiment was to measure the total absorbed dose, flux of surrounding energetic particles and spectrum of the deposited energy from high energy particles both en-route and in lunar orbit. RADOM was the first experiment to be switched on after the launch of Chandrayaan-1 and was operational until the end of the mission. This paper summarizes the observations carried out by RADOM during the entire life time (22 October 2008-31 August 2009) of the Chandrayaan-1 mission and compares the measurement by RADOM with the radiation belt models such as AP-8, AE-8 and CRRESS.

  18. Effects of solar radiation on endurance exercise capacity in a hot environment.

    Science.gov (United States)

    Otani, Hidenori; Kaya, Mitsuharu; Tamaki, Akira; Watson, Phillip; Maughan, Ronald J

    2016-04-01

    The present study investigated the effects of variations in solar radiation on endurance exercise capacity and thermoregulatory responses in a hot environment. Eight male volunteers performed four cycle exercise trials at 70 % maximum oxygen uptake until exhaustion in an environmental chamber maintained at 30 °C and 50 % relative humidity. Volunteers were tested under four solar radiation conditions: 800, 500, 250 and 0 W/m(2). Exercise time to exhaustion was less on the 800 W/m(2) trial (23 ± 4 min) than on all the other trials (500 W/m(2) 30 ± 7 min; P 0.05). Mean skin temperature was higher on the 800 W/m(2) trial than the 250 and 0 W/m(2) trials (P solar radiation increases.

  19. Radiation environment of the LHCb Calorimeters in 2010-2013 (under review)

    CERN Document Server

    Corti, Gloria

    2017-01-01

    A set of passive and active radiation detectors has been installed around and in between the LHCb calorimeter subsystems to measure different aspects of the radiation environment. Cross calibrations between various types of measurements are performed and correlated with the evolving run conditions. Measurements are compared to FLUKA simulation estimates and an evaluation of the reliability of the simulation in different running scenarios is provided. The simulation is based on a detailed geometry of the LHCb experiment and reflects the conditions of Run1 with 7 and 8 TeV CM proton-proton collision energies. A carefully characterised simulation of radiation levels in the LHCb experiment is essential in providing input for technical choices in view of the planned upgrade of the experiment for operation at higher luminosity.

  20. Protection of the environment from the effects of ionizing radiation. A report for discussion

    International Nuclear Information System (INIS)

    1999-07-01

    The acceptability of practices which involve the release of radionuclides into the environment, and of situations where residual radionuclides from accidents or improperly controlled practices exist in the environment, are generally assessed on the basis of implied radiation doses to humans. This approach is consistent with the recommendations of the International Commission on Radiological Protection (ICRP), which include the statement that 'the standard of environmental control needed to protect man to the degree currently thought desirable will ensure that other species are not put at risk'. The general applicability of this statement has been explored in previous IAEA and other publications. These concluded that the statement is generally valid but that reliance upon human based radiological protection criteria may not be adequate for all possible space or time scales. In recent years awareness of the vulnerability of the environment has increased and the need to protect it against the effects of industrial pollutants has been recognized. This trend is reflected in new and developing international policies for environmental protection. In the context of protection of the environment against ionizing radiation, the existing international approach is being challenged in some IAEA Member States and proposals are being made for strategies which provide for explicit protection of the environment. The present publication represents a first step towards establishing an internationally accepted philosophy and associated methodology for protecting the environment against ionizing radiations. The report reviews the various related issues and examines possible approaches to establishing criteria. It is intended for use in stimulating discussion on the subject in Member States. For its part, the IAEA intends to continue a programme of work in this area with the long term objective of providing specific recommendations on primary protection criteria and methods for

  1. The Resolved Stellar Population of Leo A

    Science.gov (United States)

    Tolstoy, Eline

    1996-05-01

    New observations of the resolved stellar population of the extremely metal-poor Magellanic dwarf irregular galaxy Leo A in Thuan-Gunn r, g, i, and narrowband Hα filters are presented. Using the recent Cepheid variable star distance determination to Leo A by Hoessel et al., we are able to create an accurate color-magnitude diagram (CMD). We have used the Bavesian inference method described by Tolstoy & Saha to calculate the likelihood of a Monte Carlo simulation of the stellar population of Leo A being a good match to the data within the well understood errors in the data. The magnitude limits on our data are sensitive enough to look back at ~1 Gyr of star formation history at the distance of Leo A. To explain the observed ratio of red to blue stars in the observed CMD, it is necessary to invoke either a steadily decreasing star formation rate toward the present time or gaps in the star formation history. We also compare the properties of the observed stellar population with the known spatial distribution of the H I gas and H II regions to support the conclusions from CMD modeling. We consider the possibility that currently there is a period of diminished star formation in Leo A, as evidenced by the lack of very young stars in the CMD and the faint H II regions. How the chaotic H I distribution, with no observable rotation, fits into our picture of the evolution of Leo A is as yet unclear.

  2. Combining terrestrial and LEO data to extend the GPS satellite antenna patterns to nadir angles beyond 14°

    Science.gov (United States)

    Dach, R.; Jaeggi, A.; Bock, H.; Beutler, G.; Montenbruck, O.; Schmid, R.; Andres, Y.

    2011-12-01

    The absolute phase center model igs08.atx adopted by the International GNSS Service (IGS) in 2011 is based on robot calibrations for a number of terrestrial GNSS receiver antennas and consistent correction values for the GNSS transmitter antennas estimated from data of the global IGS tracking network. As the calibration of the satellite antennas is solely based on terrestrial measurements, the estimation of their phase patterns is limited to a nadir angle of 14°. This is not sufficient for the analysis of spaceborne GPS data collected by low Earth orbiting (LEO) satellites that record observations at nadir angles of up to 17°. We use GPS tracking data from the LEO missions Jason-2, MetOp-A, GRACE, and GOCE to extend the IGS satellite antenna patterns to nadir angles beyond 14° in a combined analysis with terrestrial measurements. In order to achieve estimates that are consistent with the PCVs currently used within the IGS, GPS and LEO orbits are fixed to reprocessed solutions obtained by adopting the IGS conventional values from igs08.atx. Due to significant near-field multipath effects in the LEO spacecraft environment, it is necessary to solve for GPS (nadir-dependent only) and LEO (azimuth- and elevation-dependent) antenna patterns simultaneously. We assess the contribution of the different LEO missions to a combined solution and analyze the impact of the extended PCVs on LEO precise orbit determination results.

  3. The external gamma radiation environment from the Kiwi Phoebus, and Pewee reactors

    Science.gov (United States)

    Malenfant, R. E.

    1972-01-01

    During the past few years, ground tests of high-powered propulsion-prototype reactors have provided several opportunities to observe the external radiation environment. Reactor tests have been conducted in free air and inside of open well shields. Measurements were taken over distances ranging from contact with the pressure vessel out to greater than 5000' both during operation and after shutdown. Some measurements characteristic of each of the systems are presented and compared with results of calculations.

  4. Characterization of the radiation environment of the inner heliosphere using LRO/CRaTER and EMMREM

    Science.gov (United States)

    Joyce, Colin J.

    2016-08-01

    I provide a characterization of the radiation environment of the inner heliosphere from mid-2009 to present using measurements made by the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) aboard the Lunar Reconnaissance Orbiter (LRO) and modelling provided by the Earth-Moon-Mars Radiation Environment Module (EMMREM). In the course of this study, I analyze solar energetic particle (SEP) radiation in the form of four major solar events that occurred during this time range as well as the evolution of galactic cosmic ray (GCR) modulation over a period in which relatively calm solar conditions have resulted in the highest GCR fluxes measured in the space age. Using CRaTER measurements taken during three major solar events that occurred in 2012, I demonstrate a validation of the online PREDICCS system (Predictions of radiation from REleASE, EMMREM, and Data Incorporating CRaTER, COSTEP, and other SEP measurements), which uses EMMREM to provide near real-time radiation modelling at the Earth, Moon and Mars, finding PREDICCS to be quite accurate in modelling the peak dose rates and total accumulated doses for major solar events. Having demonstrated the accuracy of PREDICCS/EMMREM in modelling SEP events, EMMREM is used to provide an analysis of the potential radiation hazard of the extreme solar event observed by STEREO A on 23 July 2012, an event which has drawn comparisons to the historic Carrington event due to the exceptional size and record speed of the interplanetary coronal mass ejection associated with it. Such an event might be viewed as something like a worst case scenario in terms of the threat of SEP radiation to astronauts, however the evidence shown here suggests that, with the benefit of heavy protective shielding, astronauts would not have been exposed to levels of radiation that approach NASA's permissible exposure limits. These findings add to a mounting set of evidence which suggests that, contrary to conventional wisdom, the largest radiation

  5. Radiation protection of the environment. State of the art and recommendations by the IRSN

    International Nuclear Information System (INIS)

    Beaugelin-Seiller, K.; Garnier-Laplace, J.; Gilbin, R.; Simon-Cornu, M.; Baudry, M.; Deschamps, P.; Gariel, J.C.; Lecomte, J.F.; Paquet, F.; Renaud, P.; Schuler, M.

    2016-01-01

    This report notably aims at helping the GPRADE (Groupe permanent d'experts en radioprotection, pour les applications industrielles et de recherche des rayonnements ionisants, et en environnement - Permanent group of experts in radiation protection for industrial and research applications of ionizing radiations, and in environment) to build up its opinion on the French management of methods and technical regulations for the assessment of the radiological risk for the environment, or for the national transposition of the 2013/59/Euratom European directive. After a brief overview of the international, European and French legal context, the report proposes an overview of the state of the art: history, definitions, principles, regulation of radiation protection of the environment in different countries. It presents the main approaches and compares them: the CIPR approach, the Erica approach (the most used in Europe). It also discusses the compatibility of main approaches to the assessment of the radiological risk for ecosystems. It reports applications and returns on experience at the international level and within the frame of the IRSN commitment in planned, existing or emergency situations. Recommendations are formulated

  6. Use efficiency of photosynthetically active radiation by tomato plants grown in different environments

    International Nuclear Information System (INIS)

    Radin, B.; Bergamaschi, H.; Reisser Junior, C.; Barni, N.A.; Matzenauer, R.; Didone, I.A.

    2003-01-01

    Crop biomass production is related to the amount of photosynthetically active radiation intercepted and absorbed by the leaves, as well as to their efficiency of conversion of this radiant energy into chemical energy through photosynthesis. The objective of this study was to evaluate the radiation use efficiency by tomato plants (Lycopersicon esculentum Mill.) grown in different environments. Experiments were carried out in plastic-covered greenhouses with and without anti insects screens and at open air plots, in different growth periods (spring-summer and summer-autumn) during the 1999/2000 crop season. Measurements of dry above-ground biomass and leaf area index throughout both crop cycles were performed, and the incident and transmitted radiation fluxes were registered. The greenhouse with anti insects screens had less incident radiation, but resulted in higher use efficiency: 0.44 and 0.60 g dry matter mol -1 during the first and second cycles, respectively. Outside the greenhouses, there was a higher amount of incident radiation, however a lower use efficiency (0.30 and 0.32 g mol -1 for the first and second cycles, respectively), while the greenhouse without anti insects screens had intermediate values (0.45 and 0.53 g mol -1 ). (author) [pt

  7. Particle interaction and displacement damage in silicon devices operated in radiation environments

    International Nuclear Information System (INIS)

    Leroy, Claude; Rancoita, Pier-Giorgio

    2007-01-01

    Silicon is used in radiation detectors and electronic devices. Nowadays, these devices achieving submicron technology are parts of integrated circuits of large to very large scale integration (VLSI). Silicon and silicon-based devices are commonly operated in many fields including particle physics experiments, nuclear medicine and space. Some of these fields present adverse radiation environments that may affect the operation of the devices. The particle energy deposition mechanisms by ionization and non-ionization processes are reviewed as well as the radiation-induced damage and its effect on device parameters evolution, depending on particle type, energy and fluence. The temporary or permanent damage inflicted by a single particle (single event effect) to electronic devices or integrated circuits is treated separately from the total ionizing dose (TID) effect for which the accumulated fluence causes degradation and from the displacement damage induced by the non-ionizing energy-loss (NIEL) deposition. Understanding of radiation effects on silicon devices has an impact on their design and allows the prediction of a specific device behaviour when exposed to a radiation field of interest

  8. Proceedings of the international conference on radiation environment - assessment, measurement and its impact: abstract and souvenir

    International Nuclear Information System (INIS)

    2012-01-01

    The international conference on radiation environment-assessment, measurement and its impact is a major step for evolving a consensual perspective on the future course of research in radiation physics and safety aspects in the entire country and global village in wider perspectives. The attempt is to welcome novel ideas and identify the strategies for enhancing safe lives without comprising the immense benefits of radiation sciences. The conference would present progress in radiation physics research. This international conference would strengthen the chain of research activities as well act as a catalyst. In the wake of the disaster at Fukushima, Japan such research activities are the need of the hour. While radiation hazards are immense and one might be quite impulsive in criticizing the so called radiation word, but we have to invite knowledge heads all over to further this science, despite its hazards, so that it may cater to the needs of young generation in present era. The discussion between learned teachers, far sighted scientists and scholars is very relevant and need of the hour. It is expected that a sharing of the current international experiences in radiation physics research through this international exposure will help in enriching understanding of our requirements in a globalised world. We must harness maximum benefit out of this science. It is quite encouraging that the main objective of the seminar is to probe critically the state of the art expertise available and hence deciphering the future prospects available with the field which can be achieved given proper utilization of the available resources. This conference touches many such aspects. Papers relevant to INIS are indexed separately

  9. Micro-and nanodosimetry for radiobiological planning in radiotherapy and cancer risk assessment in radiation environment

    International Nuclear Information System (INIS)

    Rosenfeld, A.B.

    2006-01-01

    Full text: Microdosimetry and nanodosimetry can provide unique information for prediction of radiobiological properties of radiation, which is important in radiation therapy for accurate dose planning and in radiation protection for cancer induction risk assessment. This demand measurements of the pattern of energies deposited by ionizing radiation on cellular scale and DNA levels.Silicon microelectronics technology is offering a unique opportunity for replacing gas proportional counters (TEPC) with miniature detectors for regional microdosimetry. Silicon on Insulator (SOI) technology has been used for the development of arrays of micron size sensitive volumes for modelling energy deposited in biological cells. The challenge in silicon microdosimetry is the development of well defined sensitive volume (SV) and full charge collection deposited by ionizing radiation in the SV. First generation SOI microdosimeters were developed at CMRP and investigated in a wide range of radiation fields for proton and neutron therapies and recently on isotopic neutron sources and heavy ions with energy up to lGeV/jj,m which are typical for deep space radiation environment. Microdosimetric spectra were obtained in a phantom that are well matched to TEPC and Monte Carlo simulations. Evidence that radiations with the same LET exhibit different biological effects demand development of new sensors sensitive to the track structure of ions or the type of particle for prediction of radiobiological effect of radiation using radiobiological models. New monolithic Si AE-E telescope of cellular size for simultaneous regional microdosimetry and particle identification will be presented and results will be discussed. The new design of the SOI microdosimeter is based on 3D micron and submicron size of Si SVs. This approach allows improvement in the accuracy of the Si microdosimetry because of full charge collection and the ability to measure low LET as low as 0.01 keV/jjm, which is similar to TEPC

  10. The Radiation Environment on the Martian Surface and during MSL's Cruise to Mars

    Science.gov (United States)

    Hassler, Donald M.; Zeitlin, Cary; Wimmer-Schweingruber, Robert F.; Ehresmann, Bent; Rafkin, Scot; Martin, Cesar; Boettcher, Stephan; Koehler, Jan; Guo, Jingnan; Brinza, David E.; Reitz, Guenther; Posner, Arik; the MSL Science Team

    2013-04-01

    An important part of assessing present and past habitability of Mars is to understand and characterize "life limiting factors" on the surface, such as the radiation environment. Radiation exposure is also a major concern for future human missions and characterizing the radiation environment, both on the surface of Mars and inside the spacecraft during the cruise to Mars, provides critical information to aid in the planning for future human exploration of Mars. RAD was the first MSL instrument to start collecting data, beginning its science investigation during cruise (10 days after launch) and making the first ever measurements of the radiation environment on another planet. RAD is an energetic particle analyzer designed to characterize a broad spectrum of energetic particle radiation including galactic cosmic rays, solar energetic particles, and secondary neutrons created both in the Mars atmosphere and regolith. RAD observations consist of a time series of periodic (typically hourly) measurements of charged particles from protons (Z=1) up to iron (Z=26) for energies above >10 MeV/nucleon, as well as neutrons from 10 to ~ 100 MeV. These synoptic observations are designed to characterize both the short term variability associated with the onset of solar energetic particle events as well as the long term variability of galactic cosmic rays over the solar cycle. RAD measurements will also be used to quantify the flux of biologically hazardous radiation at the surface of Mars today, and determine how these fluxes vary on diurnal, seasonal, solar cycle and episodic (flare, storm) timescales. These measurements will allow calculations of the depth in rock or soil to which this flux, when integrated over long timescales, provides a lethal dose for known terrestrial organisms. Through such measurements, we can learn how deep below the surface life would have to be, or have been in the past, to be protected. This talk will discuss the results obtained during the ~7 months

  11. Use of COTS [commercial-off-the-shelf] Microelectronics in Radiation Environments

    International Nuclear Information System (INIS)

    Winokur, P.S.; Lum, G.K.; Shaneyfelt, M.R.; Sexton, F.W.; Hash, G.L.; Scott, L.

    1999-01-01

    This paper addresses key issues for the cost-effective use of COTS microelectronics in radiation environments that enable circuit or system designers to manage risks and ensure mission success. COTS parts with low radiation tolerance should not be used when they degrade mission critical functions or lead to premature system failure. We review several factors and tradeoffs affecting the successful application of COTS parts including (1) hardness assurance and qualification issues, (2) system hardening techniques, and (3) life-cycle costs. The paper also describes several experimental studies that address trends in total-dose, transient, and single-event radiation hardness as COTS technology scales to smaller feature sizes. As an example, the level at which dose-rate upset occurs in Samsung SRAMS increases from 1.4x10 8 rads(Si)/s for a 256K SRAM to 7.7x10 9 rads(Si)/s for a 4M SRAM, indicating unintentional hardening improvements in the design or process of a commercial technology. Additional experiments were performed to quantify variations in radiation hardness for COTS parts. In one study, only small (10-15%) variations were found in the dose-rate upset and latchup thresholds for Samsung 4M SRAMS from three different date codes. In another study, irradiations of 4M SRAMS from Samsung, Hitachi, and Toshiba indicate large differences in total-dose radiation hardness. The paper attempts to carefully define terms and clear up misunderstandings about the definitions of ''COTS'' and ''radiation-hardened'' technology

  12. Use of COTS [commercial-off-the-shelf] Microelectronics in Radiation Environments

    Energy Technology Data Exchange (ETDEWEB)

    Winokur, P.S.; Lum, G.K.; Shaneyfelt, M.R.; Sexton, F.W.; Hash, G.L.; Scott, L.

    1999-07-07

    This paper addresses key issues for the cost-effective use of COTS microelectronics in radiation environments that enable circuit or system designers to manage risks and ensure mission success. COTS parts with low radiation tolerance should not be used when they degrade mission critical functions or lead to premature system failure. We review several factors and tradeoffs affecting the successful application of COTS parts including (1) hardness assurance and qualification issues, (2) system hardening techniques, and (3) life-cycle costs. The paper also describes several experimental studies that address trends in total-dose, transient, and single-event radiation hardness as COTS technology scales to smaller feature sizes. As an example, the level at which dose-rate upset occurs in Samsung SRAMS increases from 1.4x10{sup 8} rads(Si)/s for a 256K SRAM to 7.7x10{sup 9} rads(Si)/s for a 4M SRAM, indicating unintentional hardening improvements in the design or process of a commercial technology. Additional experiments were performed to quantify variations in radiation hardness for COTS parts. In one study, only small (10-15%) variations were found in the dose-rate upset and latchup thresholds for Samsung 4M SRAMS from three different date codes. In another study, irradiations of 4M SRAMS from Samsung, Hitachi, and Toshiba indicate large differences in total-dose radiation hardness. The paper attempts to carefully define terms and clear up misunderstandings about the definitions of ''COTS'' and ''radiation-hardened'' technology.

  13. Radiation Environments and Exposure Considerations for the Multi-Mission Radioisotope Thermoelectric Generator

    International Nuclear Information System (INIS)

    Kelly, William M.; Low, Nora M.; Zillmer, Andrew; Johnson, Gregory A.; Normand, Eugene

    2006-01-01

    The Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) is the next generation (RTG) being developed by DOE to provide reliable, long-life electric power for NASA's planetary exploration programs. The MMRTG is being developed by Pratt and Whitney Rocketdyne and Teledyne Energy Systems Incorporated (TESI) for use on currently planned and projected flyby, orbital and planet landing missions. This is a significant departure from the design philosophy of the past which was to match specific mission requirements to RTG design capabilities. Undefined mission requirements provide a challenge to system designers by forcing them to put a design envelope around 'all possible missions'. These multi-mission requirements include internal and external radiation sources. Internal sources include the particles ejected by decaying Pu-238 and its daughters plus particles resulting from the interaction of these particles with other MMRTG materials. External sources include the full spectrum of charged particle radiation surrounding planets with magnetic fields and the surfaces of extraterrestrial objects not shielded by magnetic fields. The paper presents the results of investigations into the environments outlined above and the impact of radiation exposure on potential materials to be used on MMRTG and ground support personnel. Mission requirements were also reviewed to evaluate total integrated dose and to project potential shielding requirements for materials. Much of the information on mission shielding requirements was provided by NASA's Jet Propulsion Laboratory. The primary result is an ionizing radiation design curve which indicates the limits to which a particular mission can take the MMRTG in terms of ionizing radiation exposure. Estimates of personnel radiation exposure during ground handling are also provided

  14. Radioactivity in food and the environment: calculations of UK radiation doses using integrated methods

    International Nuclear Information System (INIS)

    Allott, Rob

    2003-01-01

    Dear Sir: I read with interest the paper by W C Camplin, G P Brownless, G D Round, K Winpenny and G J Hunt from the Centre for Environment, Fisheries and Aquaculture Science (CEFAS) on 'Radioactivity in food and the environment: calculations of UK radiation doses using integrated methods' in the December 2002 issue of this journal (J. Radiol. Prot. 22 371-88). The Environment Agency has a keen interest in the development of a robust methodology for assessing total doses which have been received by members of the public from authorised discharges of radioactive substances to the environment. Total dose in this context means the dose received from all authorised discharges and all exposure pathways (e.g. inhalation, external irradiation from radionuclides in sediment/soil, direct radiation from operations on a nuclear site, consumption of food etc). I chair a 'total retrospective dose assessment' working group with representatives from the Scottish Environment Protection Agency (SEPA), Food Standards Agency (FSA), National Radiological Protection Board, CEFAS and BNFL which began discussing precisely this issue during 2002. This group is a sub-group of the National Dose Assessment Working Group which was set up in April 2002 (J. Radiol. Prot. 22 318-9). The Environment Agency, Food Standards Agency and the Nuclear Installations Inspectorate previously undertook joint research into the most appropriate methodology to use for total dose assessment (J J Hancox, S J Stansby and M C Thorne 2002 The Development of a Methodology to Assess Population Doses from Multiple Source and Exposure Pathways of Radioactivity (Environment Agency R and D Technical Report P3-070/TR). This work came to broadly the same conclusion as the work by CEFAS, that an individual dose method is probably the most appropriate method to use. This research and that undertaken by CEFAS will help the total retrospective dose assessment working group refine a set of principles and a methodology for the

  15. Control of the working environment dosimetry and technical radiation protection at the RA reactor, Part I

    International Nuclear Information System (INIS)

    Ninkovic, N.; Bjelanovic, J.; Minicic, Z.; Komatina, R.; Raicevic, J.

    1984-01-01

    This report contains data and analysis of the of measured sample results collected during radiation protection control in the working environment of the RA reactor. First part contains basic exposure values and statistical review of the the total number of radiation measurements. It includes contents of radioactive gasses and effluents in the air, as well as the level of surface contamination of clothes and uncovered parts of the personnel bodies. Second part deals with the analysis of personnel doses. It was found that the maximum individual dose from external irradiation amounted to 16.9 mSV during past 10 months. Individual exposures for 9/10 of the personnel were less than 1/10 of the permissible annual exposure. Data are compared to radiation doses for last year and previous five years. Third part of this annex contains basic data about the quantity of collected radioactive waste, total quantity of contaminated and decontaminated surfaces. The last part analyzes accidents occurred at the reactor during 1984. It was found that there have been no accidents that could cause significant contamination of working surfaces and components nor radiation exposure of the personnel

  16. TEPC radiation protection dosimetry in the environment of accelerators and at nuclear facilities

    International Nuclear Information System (INIS)

    Folkerts, K.H.; Menzel, H.G.; Schuhmacher, H.; Arend, E.

    1988-01-01

    Low pressure tissue-equivalent proportional counters (TEPC) have been used to measure radiation quality and dose equivalent rates in the environment of physical and medical accelerators and at nuclear facilities. The measurements were performed with a 5.9 cm diameter spherical counter simulating a site diameter of 2 μm. A conventional pulse processing system was used. The mean quality factors for the radiation fields investigated were determined by applying different quality functions to the measured dose distributions as a function of lineal energy. The calculated quality factors for the ICRP 21 quality function for y = L yielded values in the range of Q-bar = 1.1 - 4.9, with a mean value of Q-bar = 2.3. Separation of the spectra into the photon and neutron components showed quality factors in the range of Q ph = 1.08 - 1.26 for photons and Q n = 5.2 - 17.8 for neutrons. Significant differences in radiation quality between the measurements at nuclear facilities and at therapy facilities, as well as large variations of radiation quality even within the same facility were demonstrated. (author)

  17. Study on the behavior of resistance strain gages in nuclear radiation environments

    International Nuclear Information System (INIS)

    Kumagai, Katsuaki; Yokoo, Hiroshi; Kitahara, Tanemichi; Kaieda, Keisuke

    1975-08-01

    A series of irradiation experiments were carried out on the behavior of resistance strain gages in nuclear radiation environments. The gages made of bakelite base and advance (nickel-copper alloy) wire were bonded to stainless-steel or aluminium-alloy plates. They were inserted into an in-pile helium loop TLG-1 installed in the JRR-2 reactor, and irradiated at 80 0 C for nearly 300 hours, during which the apparent strain and the leakage current through the base material between the resistance wire and the plate were measured. The results are summarized in the following: (1) The sensitivity change and the insulation-resistance deterioration of the gage are hardly observed. (2) The apparent strain observed can be divided into two components; one dependent on the radiation intensity and the other on the radiation fluence. Both of them indicate the decrease of the gage resistance. (3) The former apparent strain is possibly due to the leakage current through the base material induced by gamma-rays. The latter may be ascribed to the decrease of the wire resistance caused by the radiation damage. (4) Either the half-bridge or full-bridge method makes it possible to compensate the apparent strain and to measure static strain for a few days satisfactorily as well as dynamic strain. (auth.)

  18. Gas-to-particle conversion in the atmospheric environment by radiation-induced and photochemical reactions

    International Nuclear Information System (INIS)

    Vohra, K.G.

    1975-01-01

    During the last few years a fascinating new area of research involving ionizing radiations and photochemistry in gas-to-particle conversion in the atmosphere has been developing at a rapid pace. Two problems of major interest and concern in which this is of paramount importance are: (1) radiation induced and photochemical aerosol formation in the stratosphere and, (2) role of radiations and photochemistry in smog formation. The peak in cosmic ray intensity and significant solar UV flux in the stratosphere lead to complex variety of reactions involving major and trace constituents in this region of the atmosphere, and some of these reactions are of vital importance in aerosol formation. The problem is of great current interest because the pollutant gases from industrial sources and future SST operations entering the stratosphere could increase the aerosol burden in the stratosphere and affect the solar energy input of the troposphere with consequent ecological and climatic changes. On the other hand, in the nuclear era, the atmospheric releases from reactors and processing plants could lead to changes in the cloud nucleation behaviour of the environment and possible increase in smog formation in the areas with significant levels of radiations and conventional pollutants. A review of the earlier work, current status of the problem, and conventional pollutants. A review of the earlier work, current status of the problem, and some recent results of the experiments conducted in the author's laboratory are presented. The possible mechanisms of gas-to-particle conversion in the atmosphere have been explained

  19. Superação da dormência de cultivares de mirtileiro em ambiente protegido com cianamida hidrogenada e óleo mineral Dormancy breaking of blueberries cultivars in a protected environment with hydrogen cyanamide and mineral oil

    Directory of Open Access Journals (Sweden)

    Roberto Coletti

    2011-06-01

    Full Text Available O mirtileiro é uma frutífera de clima temperado que necessita de frio no outono/inverno. A insuficiência de frio pode provocar deficiente e desuniforme brotação e floração, com reflexos na produção. A pesquisa realizada na Universidade de Passo Fundo-RS, teve por objetivo estudar a superação da dormência de cultivares de mirtileiro (Georgiagem, Climax e Aliceblue em ambiente protegido, tratadas em 25-07-2007 com cianamida hidrogenada (CH, nas doses de 0,52% e 1,04% (1% e 2% do produto comercial Dormex®, com a adição de 0,5% de óleo mineral (OM, comparando com plantas sem tratamento. As plantas encontravam-se no terceiro ciclo vegetativo e no primeiro de produção. O plantio foi realizado em 2005, no espaçamento de 0,7 m x 2,0 m, com irrigação por gotejamento. De acordo com os resultados obtidos, a aplicação no final de julho de CH + OM concentrou e uniformizou a floração e antecipou a brotação das cvs. Georgiagem e Clímax. A cianamida hidrogenada, nas concentrações de 0,52% e 1,04% (1% e 2% de Dormex®, combinado com 0,5% de óleo mineral, não teve efeito na porcentagem de brotação, mas reduziu a produção, evidenciando efeitos fitotóxicos.Blueberry require chilling hours accumulation in the fall/winter. Insufficient cold accumulation can cause deficient and desuniform sprouting and blooming, with negative consequences on yield. The research conducted in Passo Fundo University, state of Rio Grande do Sul, had the objective of studying the dormancy breaking of blueberries cultivars (Georgiagem, Climax and Aliceblue under greenhouse conditions, submitted to treatments with hydrogen cyanamide (HC at the doses of 0.52% and 1.04% (1% and 2% of the commercial product Dormex®, with the addition of 0.5% of mineral oil (MO, and compare them to a control, without hydrogen cyanamide treatment. Planting was made in December 2005, at a 0.7 m x 2.0 m space, with drip irrigation. The plants were evaluated in the third

  20. Leo Metsari tõlkepärl / Aivar Kull

    Index Scriptorium Estoniae

    Kull, Aivar, 1955-

    2002-01-01

    Arvustus: Mann, Thomas. Lotte Weimaris / tlk. Leo Metsar. Tln. : Eesti Raamat, 2001. (Nobeli laureaat). Vaata ka: Kull, Aivar. Kulli pilk. - Tartu : Ilmamaa, 2005, lk. 68-69, pealkirjaga "Goethe, Thomas Mann ja Leo Metsar"

  1. The Plateau de Bure ASTEP Platform Test in natural radiation environment of electronic components and circuits

    International Nuclear Information System (INIS)

    Autran, J.L.; Munteanu, D.; Sauze, S.; Roche, Ph.; Gasiot, G.; Borel, J.

    2010-01-01

    Reducing the size of microelectronic devices and increasing the integration density of circuits lead (following the famous Moore's law) to an increased sensitivity of circuits to natural terrestrial radiation environment. - Such sensitivity to atmospheric particles (mainly neutrons) can cause non-destructive (soft-errors) or destructive (latch-up) failures in most electronic circuits, including volatile static memories (SRAM), object of the research work carried out since 2004 on the European Test Platform ASTER. - This paper presents in details the ASTEP platform, its location, the instruments (neutron monitor of the Plateau de Bure) and the experiences (memory tester) currently installed on the Plateau de Bure. In a second part, we also report a synthesis of the key results concerning the natural radiation sensitivity of SRAM fabricated in 130 nm and 65 nm bulk silicon technologies. (authors)

  2. Evaluation of insulation materials and composites for use in a nuclear radiation environment, phase 1

    Science.gov (United States)

    Greenhow, W. A.; Lewis, J. H.

    1972-01-01

    This study has been carried out to evaluate flight-qualified Saturn 5 materials, components, and systems for use, with or without modification, in the radiation environment of the nuclear flight system. The results reported herein are primarily intended to aid designers in their evaluation and selection of off-the-shelf equipments which may meet the stringent requirements and specifications associated with application on a reusable nuclear powered space system, i.e., the reusable nuclear shuttle. One of the factors which must be evaluated in the design of the RNS is the effects of radiation on materials; and it is toward this aspect of the overall effort that this analysis has been directed.

  3. Computer modeling characterization, and applications of Gallium Arsenide Gunn diodes in radiation environments

    Energy Technology Data Exchange (ETDEWEB)

    El- Basit, Wafaa Abd; El-Ghanam, Safaa Mohamed; Kamh, Sanaa Abd El-Tawab [Electronics Research Laboratory, Physics Department, Faculty of Women for Arts, Science and Education, Ain-Shams University, Cairo (Egypt); Abdel-Maksood, Ashraf Mosleh; Soliman, Fouad Abd El-Moniem Saad [Nuclear Materials Authority, Cairo (Egypt)

    2016-10-15

    The present paper reports on a trial to shed further light on the characterization, applications, and operation of radar speed guns or Gunn diodes on different radiation environments of neutron or γ fields. To this end, theoretical and experimental investigations of microwave oscillating system for outer-space applications were carried out. Radiation effects on the transient parameters and electrical properties of the proposed devices have been studied in detail with the application of computer programming. Also, the oscillation parameters, power characteristics, and bias current were plotted under the influence of different γ and neutron irradiation levels. Finally, shelf or oven annealing processes were shown to be satisfactory techniques to recover the initial characteristics of the irradiated devices.

  4. Overview of the atmospheric ionizing radiation environment monitoring by Bulgarian build instruments

    Science.gov (United States)

    Dachev, Tsvetan; Tomov, Borislav; Matviichuk, Yury; Dimitrov, Plamen; Spurny, Frantisek; Ploc, Ondrej; Uchihori, Yukio; Flueckiger, Erwin; Kudela, Karel; Benton, Eric

    2012-10-01

    Humans are exposed to ionizing radiation all the time, and it is known that it can induce a variety of harmful biological effects. Consequently, it is necessary to quantitatively assess the level of exposure to this radiation as the basis for estimating risks for their health. Spacecraft and aircraft crews are exposed to elevated levels of cosmic radiation of galactic and solar origin and to secondary radiation produced in the atmosphere, the vehicle structure and its contents. The aircraft crew monitoring is required by the following recommendations of the International Commission on Radiological Protection (ICRP) (ICRP 1990), the European Union (EU) introduced a revised Basic Safety Standards Directive (EC 1997) which, inter alia, included the exposure to cosmic radiation. This approach has been also adopted in other official documents (NCRP 2002). In this overview we present the results of ground based, mountain peaks, aircraft, balloon and rocket radiation environment monitoring by means of a Si-diode energy deposition spectrometer Liulin type developed first in Bulgarian Academy of Sciences (BAS) for the purposes of the space radiation monitoring at MIR and International Space Station (ISS). These spectrometers-dosemeters are further developed, calibrated and used by scientific groups in different countries. Calibration procedures of them are performed at different accelerators including runs in the CERN high-energy reference field, simulating the radiation field at 10 km altitude in the atmosphere and with heavy ions in Chiba, Japan HIMAC accelerator were performed also. The long term aircraft data base were accumulated using specially developed battery operated instrument in 2001-2009 years onboard of A310-300 aircrafts of Czech Air Lines, during 24 about 2 months runs with more than 2000 flights and 13500 flight hours on routes over the Atlantic Ocean mainly. The obtained experimental data are compared with computational models like CARI and EPCARD. The

  5. A regional study of the radiation environment of Greenham Common, Newbury District and surrounding areas

    International Nuclear Information System (INIS)

    1997-02-01

    This study was commissioned by Newbury District Council and Basingstoke and Deane Borough Council in response to public concern following disclosures about events at Greenham Common in the 1950s, and the suspicion that there may have been an accident involving a nuclear weapon leading to off-site contamination at the airbase. The Greenham Common airbase is at an advanced stage of decommissioning with parts of the site already re-developed for industrial and leisure purposes and material being removed for use in construction of the Newbury by-pass. The success of such developments is critically dependent on public confidence in the quality of the environment, both near the site, and more generally throughout the area. For this reason the study was commissioned with the aims of: I. defining the radiation environment of the whole district and parts of its surrounding areas. II. examining whether there is any evidence of radioactive contamination in the vicinity of the Greenham Common airbase. III. assessing the evidence that there may have been a release of nuclear material from the site. The work involved a collaboration between scientists from the Scottish Universities Research and Reactor Centre, who conducted gamma ray surveys to define the general radiation environment of the area, and Scientists from the University of Southampton who collected an extensive range of samples for high sensitivity radiochemical analyses. This report presents their findings and main conclusions, together with a discussion of the background to the study and its implications. (Author)

  6. Premar-2: a Monte Carlo code for radiative transport simulation in atmospheric environments

    International Nuclear Information System (INIS)

    Cupini, E.

    1999-01-01

    The peculiarities of the PREMAR-2 code, aimed at radiation transport Monte Carlo simulation in atmospheric environments in the infrared-ultraviolet frequency range, are described. With respect to the previously developed PREMAR code, besides plane multilayers, spherical multilayers and finite sequences of vertical layers, each one with its own atmospheric behaviour, are foreseen in the new code, together with the refraction phenomenon, so that long range, highly slanted paths can now be more faithfully taken into account. A zenithal angular dependence of the albedo coefficient has moreover been introduced. Lidar systems, with spatially independent source and telescope, are allowed again to be simulated, and, in this latest version of the code, sensitivity analyses to be performed. According to this last feasibility, consequences on radiation transport of small perturbations in physical components of the atmospheric environment may be analyze and the related effects on searched results estimated. The availability of a library of physical data (reaction coefficients, phase functions and refraction indexes) is required by the code, providing the essential features of the environment of interest needed of the Monte Carlo simulation. Variance reducing techniques have been enhanced in the Premar-2 code, by introducing, for instance, a local forced collision technique, especially apt to be used in Lidar system simulations. Encouraging comparisons between code and experimental results carried out at the Brasimone Centre of ENEA, have so far been obtained, even if further checks of the code are to be performed [it

  7. Law 19.056. It dictate rules to ensure the protection and radiation safety of people, goods and environment

    International Nuclear Information System (INIS)

    2013-01-01

    The objective of this law is to ensure the protection and radiation safety of personnel occupationally exposed, the public in general and the environment from the effects of ionizing radiation as well as avoid risks of contamination in radiactive sources, physical facilities and means of transport

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

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

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

    2014-01-01

    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. (paper)

  10. Simulation research for mixed radiation environment in target chamber II of BEPC II-LINAC test beam

    International Nuclear Information System (INIS)

    Tang Xinghua; Li Jiacai; Ke Zunjian; An Guangpeng; Zhang Shaoping; Yang Tao; Xu Jinzhang

    2011-01-01

    In order to get basic physical parameters of radiation environment for detector or sample irradiation experiment and optimal target material choice, Monte Carlo simulation software FLUKA is used to calculate parameters of mixed radiation environment in target chamber II on E2 line of test beam. At last, physical parameters: secondary particles differential fluencies, secondary particles angular differential cross-section, dual differential energy spectrum, dose rate distribution are acquired. (authors)

  11. NASA STD-4005: The LEO Spacecraft Charging Design Standard

    Science.gov (United States)

    Ferguson, Dale C.

    2006-01-01

    Power systems with voltages higher than about 55 volts may charge in Low Earth Orbit (LEO) enough to cause destructive arcing. The NASA STD-4005 LEO Spacecraft Charging Design Standard will help spacecraft designers prevent arcing and other deleterious effects on LEO spacecraft. The Appendices, an Information Handbook based on the popular LEO Spacecraft Charging Design Guidelines by Ferguson and Hillard, serve as a useful explanation and accompaniment to the Standard.

  12. High school students' understanding of radiation and the environment: Can museums play a role?

    Science.gov (United States)

    Henriksen, Ellen K.; Jorde, Doris

    2001-03-01

    In connection with an exhibition on radiation1-related environmental issues at the Norwegian Museum of Science and Technology, teaching units including pre- and post-visit activities were developed for visiting students. The units were centered on real-life stories concerning radiation issues that were used by the students as starting points for reflections around these issues. Using the teaching units as an evaluation instrument, students' written responses were analyzed with a dual purpose: 1) to gain insight into the understanding of and attitudes on radiation issues held by students in their final year of compulsory science instruction; and 2) to explore whether the exhibition medium may successfully convey scientific information that students find relevant and helpful in making personal judgments in environmental issues. In the present work, some prominent features of Norwegian 16-year-olds' understanding of radiation issues were identified, and it was noted that these were in many aspects similar to those described for students of other age groups and nationalities. Furthermore, it was found that a visit to the exhibition clearly provided science learning outcome for the majority of the students; however, for students who had strong alternative conceptions about the exhibition's issues, their preconceptions tended to inhibit their correct interpretation of new concepts introduced at the exhibition. We found few examples of students using scientific information from the exhibition in making personal judgments in matters concerning radiation and the environment, and we hypothesize that this may be due to a lack of practice in employing scientific understanding in this way. We believe that the use of museum exhibitions as part of a science education for scientific literacy is worth further exploration and might have increased success if new ways were found of improving the cooperation between museums and schools.

  13. Radon measurements by etched track detectors applications in radiation protection, earth sciences and the environment

    CERN Document Server

    Durrani, Saeed A

    1997-01-01

    Exposure to radon gas, which is present in the environment naturally, constitutes over half the radiation dose received by the general public annually. At present, the most widely used method of measuring radon concentration levels throughout the world, both in dwellings and in the field, is by etched track detectors - also known as Solid State Nuclear Detectors (SSNTDs). Although this is not only the most widely used method but is also the simplest and the cheapest, yet there is at present no book available on the market globally, devoted exclusively or largely to the methodology of, and deal

  14. Orbital Lifetime Analysis for Nanosatellites at LEO

    Science.gov (United States)

    Cubillos Jara, D. J.; Soliz Torrico, J. A.; Ramírez Suárez, O. L.

    2018-01-01

    Nanosatellites at low earth orbit (LEO) have multiple applications such as monitoring environmental conditions, measuring ionosphere properties, improving communications, among others. These applications have lead to increase the effort of estimating orbital lifetimes for nanosatellites because they define the maximum operational time of a mission. In this report, we estimate orbital lifetimes of nanosatellites at LEO taking into account the gravitational interaction, Earth deformations, atmospheric drag and satellite initial conditions. Highest, mean and lowest lifetimes for nanosatellites of 1U, 2U and 3U in an equatorial orbit are computed by assuming a density profile according to literature and hypothetical uncertainties.

  15. System for detecting neutrons in the harsh radiation environment of a relativistic electron beam

    International Nuclear Information System (INIS)

    Kruse, L.W.

    1978-06-01

    Newly developed detectors and procedures allow measurement of neutron yield and energy in the harsh radiation environment of a relativistic electron beam source. A new photomultiplier tube design and special gating methods provide the basis for novel time-of-flight and total-yield detectors. The technique of activation analysis is expanded to provide a neutron energy spectrometer. There is a demonstrated potential in the use of the integrated system as a valuable diagnostic tool to study particle-beam fusion, intense ion-beam interactions, and pulsed neutron sources for simulating weapons effects. A physical lower limit of 10 8 neutrons into 4π is established for accurate and meaningful measurements in the REB environment

  16. Addressing ecological effects of radiation on populations and ecosystems to improve protection of the environment against radiation: Agreed statements from a Consensus Symposium

    OpenAIRE

    Bréchignac, François; Oughton, Deborah; Mays, Claire; Barnthouse, Lawrence; Beasley, James C.; Bonisoli-Alquati, Andrea; Bradshaw, Clare; Brown, Justin; Dray, Stéphane; Geras'kin, Stanislav; Glenn, Travis; Higley, Kathy; Ishida, Ken; Kapustka, Lawrence; Kautsky, Ulrik

    2016-01-01

    This paper reports the output of a consensus symposium organized by the International Union of Radioecology in November 2015. The symposium gathered an academically diverse group of 30 scientists to consider the still debated ecological impact of radiation on populations and ecosystems. Stimulated by the Chernobyl and Fukushima disasters? accidental contamination of the environment, there is increasing interest in developing environmental radiation protection frameworks. Scientific research c...

  17. Application of the Self Calibrating Emissivity and/or Transmissivity Independent Multiwavelength Pyrometer in an Intense Ambient Radiation Environment

    Science.gov (United States)

    Ng, Daniel

    1996-01-01

    The NASA self calibrating multiwavelength pyrometer is a recent addition to the list of pyrometers used in remote temperature measurement in research and development. The older one-color, two-color, and the disappearing filament pyrometers, as well as the multicolor and early multiwavelength pyrometers, all do not operate successfully in situations in which strong ambient radiation coexists with radiation originating from the measured surface. In such situations radiation departing from the target surface arrives at the pyrometer together with radiation coming from another source either directly or through reflection. Unlike the other pyrometers, the self calibrating multiwavelength pyrometer can still calibrate itself and measure the temperatures in this adverse environment.

  18. Net radiation and soil heat flux in natural and protected environments cropped with cucumber

    International Nuclear Information System (INIS)

    Galvani, E.; Escobedo, J.F.; Pereira, A.B.

    2001-01-01

    Net radiation, global solar radiation and heat flux from/to the soil both inside and outside greenhouses with polyethylene cover throughout the fall-winter and spring-summer seasons have been assessed at the research station of the Universidade Estadual Paulista, Campus of Botucatu, State of São Paulo, Brazil. Throughout the cycles of the experiment, both environments scrutinized in the current study were cultivated with cucumber crop - Aoday, Hokuroo - a variety of undetermined growth habit. The results indicated that the greenhouse with polyethylene cover tended to decrease the intensity of solar radiation incidence per unity of area throughout the diurnal period, as well as losses from emission during the nighttime. The transmissivity of polyethylene was altered as a function of the day of the year and exposition time of the material, changing from 70.8% at the winter to 74.9% at the summer seasons. The heat flux from/to the soil during the spring-summer cycle was dependent of the leaf area of the crop [pt

  19. Transfer of Real-time Dynamic Radiation Environment Assimilation Model; Research to Operation

    Science.gov (United States)

    Cho, K. S. F.; Hwang, J.; Shin, D. K.; Kim, G. J.; Morley, S.; Henderson, M. G.; Friedel, R. H.; Reeves, G. D.

    2015-12-01

    Real-time Dynamic Radiation Environment Assimilation Model (rtDREAM) was developed by LANL for nowcast of energetic electrons' flux at the radiation belt to quantify potential risks from radiation damage at the satellites. Assimilated data are from multiple sources including LANL assets (GEO, GPS). For transfer from research to operation of the rtDREAM code, LANL/KSWC/NOAA makes a Memorandum Of Understanding (MOU) on the collaboration between three parts. By this MOU, KWSC/RRA provides all the support for transitioning the research version of DREAM to operations. KASI is primarily responsible for providing all the interfaces between the current scientific output formats of the code and useful space weather products that can be used and accessed through the web. In the second phase, KASI will be responsible in performing the work needed to transform the Van Allen Probes beacon data into "DREAM ready" inputs. KASI will also provide the "operational" code framework and additional data preparation, model output, display and web page codes back to LANL and SWPC. KASI is already a NASA partnering ground station for the Van Allen Probes' space weather beacon data and can here show use and utility of these data for comparison between rtDREAM and observations by web. NOAA has offered to take on some of the data processing tasks specific to the GOES data.

  20. Micronuclei as biomarkers of genotoxicity of gamma radiation in aquatic environments

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Luanna R.S.; Silva, Edvane B.; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (GERAR/DEN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia; Silva, Ronaldo C. da [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Genetica; Amancio, Francisco F. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia. Lab. de Radiobiologia

    2011-07-01

    Ionizing radiation is a genotoxic agent, inducing gene mutations and cellular death. Several efforts have been defendants in the development of techniques for measurement of radiation damage in biological systems. Among these techniques, micronuclei test has been showing as a great bio marker of DNA damage, being used in environmental monitoring to detect genotoxic agents in the environment. Additionally, organisms as Biomphalaria glabrata, freshwater molluscs, presents itself as an excellent model to assess damage caused by physical and chemical agents, due their biological and environmental characteristics. The snails were divided into groups of 5 individuals exposed to doses of 0 (control), 25, 35, 45 and 55 Gy of {sup 60}Co. After 48 hours of irradiation, the hemo lymph was collected and prepared the slides, which were stained with Giemsa and analyzed the cellular changes in haemocytes Statistical analysis was accomplished through chi-square test, ANOVA and Tukey test (p< 0,05). The results indicated that B. glabrata showed to be sensitive to gamma radiation. The snails irradiated with 35 Gy showed a decrease of haemocytes, while that of 55 Gy increased. Cellular and morphological changes were observed at doses of 35, 45 and 55 Gy and the dose of 55 Gy, the most radiotoxic. (author)

  1. Micronuclei as biomarkers of genotoxicity of gamma radiation in aquatic environments

    International Nuclear Information System (INIS)

    Silva, Luanna R.S.; Silva, Edvane B.; Melo, Ana M.M.A.; Silva, Ronaldo C. da; Amancio, Francisco F.

    2011-01-01

    Ionizing radiation is a genotoxic agent, inducing gene mutations and cellular death. Several efforts have been defendants in the development of techniques for measurement of radiation damage in biological systems. Among these techniques, micronuclei test has been showing as a great bio marker of DNA damage, being used in environmental monitoring to detect genotoxic agents in the environment. Additionally, organisms as Biomphalaria glabrata, freshwater molluscs, presents itself as an excellent model to assess damage caused by physical and chemical agents, due their biological and environmental characteristics. The snails were divided into groups of 5 individuals exposed to doses of 0 (control), 25, 35, 45 and 55 Gy of 60 Co. After 48 hours of irradiation, the hemo lymph was collected and prepared the slides, which were stained with Giemsa and analyzed the cellular changes in haemocytes Statistical analysis was accomplished through chi-square test, ANOVA and Tukey test (p< 0,05). The results indicated that B. glabrata showed to be sensitive to gamma radiation. The snails irradiated with 35 Gy showed a decrease of haemocytes, while that of 55 Gy increased. Cellular and morphological changes were observed at doses of 35, 45 and 55 Gy and the dose of 55 Gy, the most radiotoxic. (author)

  2. The selection of radiation tolerant electrical/electronic components for gamma radiation environments in the nuclear power industry

    International Nuclear Information System (INIS)

    Garlick, D.R.

    1984-09-01

    This report briefly describes the mechanisms, units and effects of 1 MeV range gamma radiation on electrical/electronic components and materials. Information is tabulated on the gamma radiation tolerance of a wide range of components and materials. A radiation testing service, based at Harwell, is described. Lists of interested manufacturers and organisations are given. (author)

  3. Markedly enhanced absorption and direct radiative forcing of black carbon under polluted urban environments.

    Science.gov (United States)

    Peng, Jianfei; Hu, Min; Guo, Song; Du, Zhuofei; Zheng, Jing; Shang, Dongjie; Levy Zamora, Misti; Zeng, Limin; Shao, Min; Wu, Yu-Sheng; Zheng, Jun; Wang, Yuan; Glen, Crystal R; Collins, Donald R; Molina, Mario J; Zhang, Renyi

    2016-04-19

    Black carbon (BC) exerts profound impacts on air quality and climate because of its high absorption cross-section over a broad range of electromagnetic spectra, but the current results on absorption enhancement of BC particles during atmospheric aging remain conflicting. Here, we quantified the aging and variation in the optical properties of BC particles under ambient conditions in Beijing, China, and Houston, United States, using a novel environmental chamber approach. BC aging exhibits two distinct stages, i.e., initial transformation from a fractal to spherical morphology with little absorption variation and subsequent growth of fully compact particles with a large absorption enhancement. The timescales to achieve complete morphology modification and an absorption amplification factor of 2.4 for BC particles are estimated to be 2.3 h and 4.6 h, respectively, in Beijing, compared with 9 h and 18 h, respectively, in Houston. Our findings indicate that BC under polluted urban environments could play an essential role in pollution development and contribute importantly to large positive radiative forcing. The variation in direct radiative forcing is dependent on the rate and timescale of BC aging, with a clear distinction between urban cities in developed and developing countries, i.e., a higher climatic impact in more polluted environments. We suggest that mediation in BC emissions achieves a cobenefit in simultaneously controlling air pollution and protecting climate, especially for developing countries.

  4. Ultra Low Outgassing silicone performance in a simulated space ionizing radiation environment

    Science.gov (United States)

    Velderrain, M.; Malave, V.; Taylor, E. W.

    2010-09-01

    The improvement of silicone-based materials used in space and aerospace environments has garnered much attention for several decades. Most recently, an Ultra Low Outgassing™ silicone incorporating innovative reinforcing and functional fillers has shown that silicone elastomers with unique and specific properties can be developed to meet applications requiring stringent outgassing requirements. This paper will report on the next crucial step in qualifying these materials for spacecraft applications requiring chemical and physical stability in the presence of ionizing radiation. As a first step in this process, selected materials were irradiated with Co-60 gamma-rays to simulate the total dose received in near- Earth orbits. The paper will present pre-and post-irradiation response data of Ultra Low Outgassing silicone samples exposed under ambient air environment coupled with measurements of collected volatile condensable material (CVCM) and total mass loss (TML) per the standard conditions in ASTM E 595. The data will show an insignificant effect on the CVCMs and TMLs after exposure to various dosages of gamma radiation. This data may favorably impact new applications for these silicone materials for use as an improved sealant for space solar cell systems, space structures, satellite systems and aerospace systems.

  5. Geography, environment and organismal traits in the diversification of a major tropical herbaceous angiosperm radiation

    Science.gov (United States)

    2018-01-01

    Abstract The generation of plant diversity involves complex interactions between geography, environment and organismal traits. Many macroevolutionary processes and emergent patterns have been identified in different plant groups through the study of spatial data, but rarely in the context of a large radiation of tropical herbaceous angiosperms. A powerful system for testing interrelated biogeographical hypotheses is provided by the terrestrial bromeliads, a Neotropical group of extensive ecological diversity and importance. In this investigation, distributional data for 564 species of terrestrial bromeliads were used to estimate variation in the position and width of species-level hydrological habitat occupancy and test six core hypotheses linking geography, environment and organismal traits. Taxonomic groups and functional types differed in hydrological habitat occupancy, modulated by convergent and divergent trait evolution, and with contrasting interactions with precipitation abundance and seasonality. Plant traits in the Bromeliaceae are intimately associated with bioclimatic differentiation, which is in turn strongly associated with variation in geographical range size and species richness. These results emphasize the ecological relevance of structural-functional innovation in a major plant radiation. PMID:29479409

  6. External radiation monitoring in TAPS and RAPS environs (1980-81) using TLD

    International Nuclear Information System (INIS)

    Basu, A.S.; Nambi, K.S.V.; Sunta, C.M.

    1983-01-01

    Results of environmental external radiation monitoring using quarterly integrated TLD measurements are presented for environments of the Tarapur Atomic Power Station (TAPS) and the Rajasthan Atomic Power Station (RAPS) for the two year monitoring period (1980-81). The data fit into the unimodal log-normal distribution except for locations where gaseous radioactivity escaping from the plant makes a significant contribution. The average natural radiation background in TAPS and RAPS environment is estimated to be 59.6 +- 4.7 mR yr -1 and 65.1 +- 9.8 mR yr -1 respectively. Contribution from the plant superimposed over the natural level leads frequently to bi-normal distribution. The effect of stack-released gaseous radioactivity is seen in locations within 1.6 km of TAPS: for example Ghivoli village registered an excess of 9.3 mR yr -1 over the natural background. The quarterly background values indicate minor temporal and spatial variations which can be attributed to changes in natural as well as stack released radioactivity. (author)

  7. Using ecosystem science to improve protection of the environment from radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bradshaw, C. [Stockholm University (Sweden); Brechignac, F. [IUR / IRSN (France); Barnthouse, L. [LWB Environmental Services Inc. (United States); Brown, J. [Norwegian Radiation Protection Authority - NRPA (Norway); Forbes, V. [University of Lincoln (United Kingdom); Kapustka, L. [LC LK Consultancy (Canada); Kautsky, U. [Svensk Kaernbraenslehantering AB - SKB (Sweden)

    2014-07-01

    The ecosystem approach (EA) involves considering the impacts of an anthropogenic stressor at the ecosystem level because this is usually the ultimate goal of environmental protection. As such, EA includes population, community and ecosystem effects, structural and functional effects, indirect effects due to ecological interactions between species, dynamic interactions, positive or negative feedback loops, and potential synergistic or antagonistic effects of multiple stressors (both anthropogenic and natural). All such effects better reflect the reality of the impact of a contamination scenario than if assessments are restricted to considering effects to individual organisms or species. Such effects may be greater or lesser than expected from studies of individual organisms or species, so not considering them may result in under- or overestimation of risk, respectively. EA is a term that is widely used in environmental assessment, management and legislation in a number of regulatory fields (e.g., radiation protection, chemicals legislation, fisheries policy, international biodiversity conventions). However, although its justification is now well established in a wide range of environment protection contexts, its practical use is still unclear due to poorly defined protection goals and assessment endpoints, making its implementation difficult. This paper presents the initial findings of a newly formed follow-up task group of the International Union of Radioecology whose aims are to identify ways to put the EA into practice when considering protection of the environment from radiation. Drawing on knowledge and experience from a range of fields, we summarise the types of ecosystem processes, goods and services that might be included when using this approach, the science that supports the use of the EA, and the methodological challenges that need to be addressed when implementing the EA in the field of radiation protection. Document available in abstract form only

  8. Radiation

    International Nuclear Information System (INIS)

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  9. Role of the UV external radiation field on the presence of astrophysical ices in protostellars environments

    Science.gov (United States)

    Robson Monteiro Rocha, Will; Pilling, Sergio

    2016-07-01

    The astrophysical ices survival is directly related with the temperature and ionizing radiation field in protostellars environments such as disks and envelopes. Computational models has shown that pure volatile molecules like CO and CH _{4} should survive only inside densest regions of molecular clouds or protoplanetary disks On the other hand, solid molecules such as H _{2}O and CH _{3}OH can be placed around 5 - 10 AU from the central protostar. Unlike of the previous models, we investigate the role of the UV external radiation field on the presence of ices in disks and envelopes. Once that a star-forming region is composed by the formation of many protostars, the external radiation field should be an important component to understand the real localization of the ices along the sight line. To address this topic it was employed the radiative transfer code RADMC-3D based on the Monte Carlo method. The code was used to model the spectrum and the near-infrared image of Elias 29. The initial parameters of the disk and envelope was taken from our previous paper (Rocha & Pilling (2015), ApJ 803:18). The opacities of the ices were calculated from the complex refractive index obtained at laboratory experiments perfomed at Grand Accélerateur National d'Íons Lourds (GANIL), by using the NKABS code from Rocha & Pilling (2014), SAA 123:436. The partial conclusions that we have obtained shows that pure CO volatile molecule cannot be placed at disk or envelope of Elias 29, unlike shown in our paper about Elias 29. Once it was observed in Elias 29 spectrum obtained with Infrared Space Observatory (ISO) between 2.5 - 190 μm, this molecule should be placed in foreground molecular clouds or trapped in the water ice matrix. The next calculations will be able to show where are placed the ices such as CH _{3}OH and CH _{3}CHO observed in Elias 29 spectrum.

  10. Europa's surface radiation environment and considerations for in-situ sampling and biosignature detection

    Science.gov (United States)

    Nordheim, T.; Paranicas, C.; Hand, K. P.

    2017-12-01

    Jupiter's moon Europa is embedded deep within the Jovian magnetosphere and is thus exposed to bombardment by charged particles, from thermal plasma to more energetic particles at radiation belt energies. In particular, energetic charged particles are capable of affecting the uppermost layer of surface material on Europa, in some cases down to depths of several meters (Johnson et al., 2004; Paranicas et al., 2009, 2002). Examples of radiation-induced surface alteration include sputtering, radiolysis and grain sintering; processes that are capable of significantly altering the physical properties of surface material. Radiolysis of surface ices containing sulfur-bearing contaminants from Io has been invoked as a possible explanation for hydrated sulfuric acid detected on Europa's surface (Carlson et al., 2002, 1999) and radiolytic production of oxidants represents a potential source of energy for life that could reside within Europa's sub-surface ocean (Chyba, 2000; Hand et al., 2007; Johnson et al., 2003; Vance et al., 2016). Accurate knowledge of Europa's surface radiation environment is essential to the interpretation of space and Earth-based observations of Europa's surface and exosphere. Furthermore, future landed missions may seek to sample endogenic material emplaced on Europa's surface to investigate its chemical composition and to search for biosignatures contained within. Such material would likely be sampled from the shallow sub-surface, and thus, it becomes crucial to know to which degree this material is expected to have been radiation processed.Here we will present modeling results of energetic electron and proton bombardment of Europa's surface, including interactions between these particles and surface material. In addition, we will present predictions for biosignature destruction at different geographical locations and burial depths and discuss the implications of these results for surface sampling by future missions to Europa's surface.

  11. Challenging Christianity: Leo Tolstoy and Religious Education

    Science.gov (United States)

    Moulin, Dan

    2009-01-01

    The religious thought of Russian novelist Leo Tolstoy is a well documented but often overlooked example of unorthodox Christianity. This paper uses the example of Tolstoy's religious thinking to question the integrity of the current representation of Christianity in UK schools. It also uses Tolstoy's criticism of orthodox Christianity to suggest a…

  12. The Ancient stellar population of Leo A.

    NARCIS (Netherlands)

    Saha, Abhijit; Fiorentino, Giuliana; Tolstoy, Eline; Cole, Andrew

    The primary goal of our proposal is the characterisation of the oldest stellar populations in Leo A using the properties of ancient RR Lyrae variable stars as tracers. Well known and long established correlations exist between the periods and luminosities of RR Lyrae variable stars and their ages

  13. In Memory of Leo P. Kadanoff

    Science.gov (United States)

    Wegner, Franz J.

    2017-05-01

    Leo Kadanoff has worked in many fields of statistical mechanics. His contributions had an enormous impact. This holds in particular for critical phenomena, where he explained Widom's homogeneity laws by means of block-spin transformations and laid the basis for Wilson's renormalization group equation. I had the pleasure to work in his group for 1 year. A short historical account is given.

  14. What Happened to Leo P's Metals?

    Science.gov (United States)

    Kohler, Susanna

    2015-12-01

    Measurements of metal abundances in galaxies present a conundrum: compared to expectations, there are not nearly enough metals observed within galaxies. New observations of a nearby dwarf galaxy may help us understand where this enriched material went.Removal ProcessesStar formation is responsible for the build-up of metals (elements heavier than helium) in a galaxy. But when we use a galaxys star-formation history to estimate the amount of enriched material it should contain, our predictions are inconsistent with measured abundances: large galaxies contain only about 2025% of the expected metals, and small dwarf galaxies contain as little as 1%!So what happens to galaxies metals after they have been formed? The favored explanation is that metals are removed from galaxies via stellar feedback: stars that explode in violent supernovae can drive high-speed winds, expelling the enriched material from a galaxy. This process should be more efficient in low-mass galaxies due to their smaller gravitational wells, which would explain why low-mass galaxies have especially low metallicities.But external processes may also contribute to the removal of metals, such as tidal stripping during interactions between galaxies. To determine the role of stellar feedback alone, an ideal test would be to observe an isolated low-mass, star-forming galaxy i.e., one that is not affected by external processes.Luckily, such an isolated, low-mass galaxy has recently been discovered just outside of the Local Group: Leo P, a gas-rich dwarf galaxy with a total stellar mass of 5.6 x 105 solar masses.Isolated ResultsPercentage of oxygen lost in Leo P compared to the percentage of metals lost in three other, similar-size dwarfs that are not isolated. If the gas-phase oxygen in Leo P were removed, Leo Ps measurements would be consistent with those of the other dwarfs. [McQuinn et al. 2015]Led by Kristen McQuinn (University of Minnesota, University of Texas at Austin), a team of researchers has used

  15. Radiation protection measurement techniques and the challenges encountered in industrial and medical environments

    International Nuclear Information System (INIS)

    2013-01-01

    Nowadays everybody is concerned by the use of ionizing radiations for diagnostic and therapy purposes. Radiation protection regulatory requirements are becoming more and more constraining and have an impact on the performance criteria required for measurement systems. The measurement of some radiation protection data requires the use of complex and costly devices, leading to hardly manageable constraints for the users. Do they have to be systematically implemented? How is it possible to reduce, control and optimize the medical exposures using new methodological approaches? During this conference the participants have shed light on some concrete situations and realisations in the environmental, nuclear industry and medical domains. The document brings together 34 presentations (slides) dealing with: 1 - Environmental monitoring and measurement meaning (P.Y. Emidy (EDF)); human radiation protection and measurement meaning (A. Rannou (IRSN)); Eye lens dosimetry, why and how? (J.M. Bordy (CEA)); critical and reasoned approach of the ISO 11929 standard about decision threshold and detection limit (A. Vivier (CEA)); Samples collection and low activities measurement in the environment (D. Claval (IRSN)); Dosemeters calibration, what is new? (J.M. Bordy (CEA)); Appropriateness of measurement means for radiological controls (P. Tranchant (Techman Industrie)); Pulsed fields dosimetric reference for interventional diagnosis (M. Denoziere (CEA)); Pulsed complex fields dosimetry (F. Trompier (IRSN)); DOSEO: a tool for dose optimization in radiological imaging (C. Adrien (CEA)); Eye lens dosimetry (R. Kramar, A. De Vita (AREVA)); Eye lens dosimetry - workers exposure and proper radiation protection practices (I. Clairand (IRSN)); Individual neutrons dosimetry - status of existing standards (F. Queinnec (IRSN)); Complex field neutron spectroscopy: any new tool? (V. Lacoste (IRSN)); Photon mini-beams dosimetry in radiotherapy: stakes and protocols (C. Huet (IRSN)); Reference and

  16. Investigation of innovative radiation imaging method and system for radiological environments

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, H. [School of Biomedical Engineering, Korea University, Seoul (Korea, Republic of); Joung, J., E-mail: jinhun.joung@nucaremed.com [School of Biomedical Engineering, Korea University, Seoul (Korea, Republic of); Nucare, Inc., Incheon (Korea, Republic of); Kim, Y. [School of Biomedical Engineering, Korea University, Seoul (Korea, Republic of); Nucare, Inc., Incheon (Korea, Republic of); Lee, K. [School of Biomedical Engineering, Korea University, Seoul (Korea, Republic of)

    2017-03-01

    We have developed a novel imaging method that can be applied to most applications in the field of radiological environment imaging. It resolves either two-dimensional (2D) or three-dimensional (3D) distributions of radioactive sources in applications for homeland security, environmental monitoring, radiation contamination monitoring, baggage inspection, nuclear power plant monitoring, and more. The proposed imaging method uses a simple detector configured as a radiation-counting detector with spectroscopic capabilities. The detector module consists of two components: a flat field-of-view (FOV) collimator with a 30° FOV opening and a typical single-channel radiation detector made of a 2 in.×2 in. NaI(Tl) scintillator coupled to a 2 in photomultiplier tube (PMT). This simple detector module makes it possible to develop a cost-effective imaging system and provide design freedom in extending the system configuration to include one-dimensional (1D) or 2D detector-array shapes to meet the needs of various applications. One of most distinctive features of the new imaging method is that it uses only a pair of 2D projections to obtain a 3D reconstruction. The projections are measured by the proposed detector module at two positions orthogonal to one another; the measured projections are manipulated to enhance the resolution of the reconstructed 3D image. The imaging method comprises several steps performed consecutively: projection measurement, energy re-binning, projection separation, resolution and attenuation recovery, image reconstruction, and image consolidation and quantitative analysis. The resolution and attenuation recovery step provides the most distinctive and important processing by which the poor quality of projection data is enhanced. Such poor quality is mainly due to the use of a simple detector with a wide-opening flat FOV collimator. Simulation and experimental studies have been conducted to validate the proposed method. In this investigation, we

  17. Organization and operation of the sixth international symposium on the natural radiation environment (NRE VI). Final report

    International Nuclear Information System (INIS)

    Hopke, P.K.

    1995-01-01

    An important source of human exposure to radiation is the natural world including cosmic rays, cosmogonic radionuclides, natural terrestrial radionuclides, and radon isotopes and its decay products. Considerable effort is being expended on a worldwide basis to characterize the exposure to the natural radiation environment and determine the important pathways for the exposure to result in dose to tissue that leads to injury and disease. The problem of background exposure to naturally occurring radioactivity has been the subject of research since the initial discovery of the radioactivity of uranium and thorium. However, with the advent of artificial sources of radiation with both benefits (medical x-rays and nuclear medicine), and harm (Chernobyl fallout), the nature and magnitude of the natural radiation environment and the effects on various populations are important in the development of overall public health strategies as ALARA principles are applied. To facilitate the exchange of information and the review of uncertainties and scientific research priorities, a series of 5 international meetings on Natural Radiation Environment, 1963, 1987, 1991. This conference (Montreal, 1995) covers the range of natural radiation environments that give rise to human exposure and dose. This document is a program summary

  18. Addressing ecological effects of radiation on populations and ecosystems to improve protection of the environment against radiation: Agreed statements from a Consensus Symposium☆

    Science.gov (United States)

    Bréchignac, François; Oughton, Deborah; Mays, Claire; Barnthouse, Lawrence; Beasley, James C.; Bonisoli-Alquati, Andrea; Bradshaw, Clare; Brown, Justin; Dray, Stéphane; Geras’kin, Stanislav; Glenn, Travis; Higley, Kathy; Ishida, Ken; Kapustka, Lawrence; Kautsky, Ulrik; Kuhne, Wendy; Lynch, Michael; Mappes, Tapio; Mihok, Steve; Møller, Anders P.; Mothersill, Carmel; Mousseau, Timothy A.; Otaki, Joji M.; Pryakhin, Evgeny; Rhodes, Olin E.; Salbu, Brit; Strand, Per; Tsukada, Hirofumi

    2016-01-01

    This paper reports the output of a consensus symposium organized by the International Union of Radioecology in November 2015. The symposium gathered an academically diverse group of 30 scientists to consider the still debated ecological impact of radiation on populations and ecosystems. Stimulated by the Chernobyl and Fukushima disasters’ accidental contamination of the environment, there is increasing interest in developing environmental radiation protection frameworks. Scientific research conducted in a variety of laboratory and field settings has improved our knowledge of the effects of ionizing radiation on the environment. However, the results from such studies sometimes appear contradictory and there is disagreement about the implications for risk assessment. The Symposium discussions therefore focused on issues that might lead to different interpretations of the results, such as laboratory versus field approaches, organism versus population and ecosystemic inference strategies, dose estimation approaches and their significance under chronic exposure conditions. The participating scientists, from across the spectrum of disciplines and research areas, extending also beyond the traditional radioecology community, successfully developed a constructive spirit directed at understanding discrepancies. From the discussions, the group has derived seven consensus statements related to environmental protection against radiation, which are supplemented with some recommendations. Each of these statements is contextualized and discussed in view of contributing to the orientation and integration of future research, the results of which should yield better consensus on the ecological impact of radiation and consolidate suitable approaches for efficient radiological protection of the environment. PMID:27058410

  19. Addressing ecological effects of radiation on populations and ecosystems to improve protection of the environment against radiation: Agreed statements from a Consensus Symposium.

    Science.gov (United States)

    Bréchignac, François; Oughton, Deborah; Mays, Claire; Barnthouse, Lawrence; Beasley, James C; Bonisoli-Alquati, Andrea; Bradshaw, Clare; Brown, Justin; Dray, Stéphane; Geras'kin, Stanislav; Glenn, Travis; Higley, Kathy; Ishida, Ken; Kapustka, Lawrence; Kautsky, Ulrik; Kuhne, Wendy; Lynch, Michael; Mappes, Tapio; Mihok, Steve; Møller, Anders P; Mothersill, Carmel; Mousseau, Timothy A; Otaki, Joji M; Pryakhin, Evgeny; Rhodes, Olin E; Salbu, Brit; Strand, Per; Tsukada, Hirofumi

    2016-07-01

    This paper reports the output of a consensus symposium organized by the International Union of Radioecology in November 2015. The symposium gathered an academically diverse group of 30 scientists to consider the still debated ecological impact of radiation on populations and ecosystems. Stimulated by the Chernobyl and Fukushima disasters' accidental contamination of the environment, there is increasing interest in developing environmental radiation protection frameworks. Scientific research conducted in a variety of laboratory and field settings has improved our knowledge of the effects of ionizing radiation on the environment. However, the results from such studies sometimes appear contradictory and there is disagreement about the implications for risk assessment. The Symposium discussions therefore focused on issues that might lead to different interpretations of the results, such as laboratory versus field approaches, organism versus population and ecosystemic inference strategies, dose estimation approaches and their significance under chronic exposure conditions. The participating scientists, from across the spectrum of disciplines and research areas, extending also beyond the traditional radioecology community, successfully developed a constructive spirit directed at understanding discrepancies. From the discussions, the group has derived seven consensus statements related to environmental protection against radiation, which are supplemented with some recommendations. Each of these statements is contextualized and discussed in view of contributing to the orientation and integration of future research, the results of which should yield better consensus on the ecological impact of radiation and consolidate suitable approaches for efficient radiological protection of the environment. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. The Los Alamos.confEic Radiation Environment Assimilation Model (DREAM) for Space Weather Specification and Forecasting

    Science.gov (United States)

    Reeves, G.; Freidel, R.; Chen, Y.; Koller, J.; Henderson, M.

    The Dynamic Radiation Environment Assimilation Model (DREAM) was developed at Los Alamos.confEnal Laboratory to assess, quantify, and predict the hazards from the natural space environment and the anthropogenic environment produced by high altitude nuclear explosions (HANE). DREAM was initially developed as a basic research activity to understand and predict the dynamics of the Earth's Van Allen radiation belts. It uses Kalman filter techniques to assimilate data from space environment instruments with a physics-based model of the radiation belts. DREAM can assimilate data from a variety of types of instruments and data with various levels of resolution and fidelity by assigning appropriate uncertainties to the observations. Data from any spacecraft orbit can be assimilated but DREAM was designed to function with as few as two spacecraft inputs: one from geosynchronous orbit and one from GPS orbit. With those inputs, DREAM can be used to predict the environment at any satellite in any orbit whether space environment data are available in those orbits or not. Even with very limited data input and relatively simple physics models, DREAM specifies the space environment in the radiation belts to a high level of accuracy. DREAM has been extensively tested and evaluated as we transition from research to operations. We report here on one set of test results in which we predict the environment in a highly-elliptical polar orbit. We also discuss long-duration reanalysis for spacecraft design, using DREAM for real-time operations, and prospects for 1-week forecasts of the radiation belt environment.

  1. Ionizing radiation sources: very diversified means, multiple applications and a changing regulatory environment. Conference proceedings

    International Nuclear Information System (INIS)

    2011-11-01

    This document brings together the available presentations given at the conference organised by the French society of radiation protection about ionizing radiation source means, applications and regulatory environment. Twenty eight presentations (slides) are compiled in this document and deal with: 1 - Overview of sources - some quantitative data from the national inventory of ionizing radiation sources (Yann Billarand, IRSN); 2 - Overview of sources (Jerome Fradin, ASN); 3 - Regulatory framework (Sylvie Rodde, ASN); 4 - Alternatives to Iridium radiography - the case of pressure devices at the manufacturing stage (Henri Walaszek, Cetim; Bruno Kowalski, Welding Institute); 5 - Dosimetric stakes of medical scanner examinations (Jean-Louis Greffe, Charleroi hospital of Medical University); 6 - The removal of ionic smoke detectors (Bruno Charpentier, ASN); 7 - Joint-activity and reciprocal liabilities - Organisation of labour risk prevention in case of companies joint-activity (Paulo Pinto, DGT); 8 - Consideration of gamma-graphic testing in the organization of a unit outage activities (Jean-Gabriel Leonard, EDF); 9 - Radiological risk control at a closed and independent work field (Stephane Sartelet, Areva); 10 - Incidents and accidents status and typology (Pascale Scanff, IRSN); 11 - Regional overview of radiation protection significant events (Philippe Menechal, ASN); 12 - Incident leading to a tritium contamination in and urban area - consequences and experience feedback (Laurence Fusil, CEA); 13 - Experience feedback - loss of sealing of a calibration source (Philippe Mougnard, Areva); 14 - Blocking incident of a 60 Co source (Bruno Delille, Salvarem); 15 - Triggering of gantry's alarm: status of findings (Philippe Prat, Syctom); 16 - Non-medical electric devices: regulatory changes (Sophie Dagois, IRSN; Jerome Fradin, ASN); 17 - Evaluation of the dose equivalent rate in pulsed fields: method proposed by the IRSN and implementation test (Laurent Donadille, IRSN

  2. Addressing ecological effects of radiation on populations and ecosystems to improve protection of the environment against radiation: Agreed statements from a Consensus Symposium

    International Nuclear Information System (INIS)

    Bréchignac, François; Oughton, Deborah; Mays, Claire; Barnthouse, Lawrence; Beasley, James C.; Bonisoli-Alquati, Andrea; Bradshaw, Clare; Brown, Justin; Dray, Stéphane; Geras'kin, Stanislav

    2016-01-01

    This paper reports the output of a consensus symposium organized by the International Union of Radioecology in November 2015. The symposium gathered an academically diverse group of 30 scientists to consider the still debated ecological impact of radiation on populations and ecosystems. Stimulated by the Chernobyl and Fukushima disasters' accidental contamination of the environment, there is increasing interest in developing environmental radiation protection frameworks. Scientific research conducted in a variety of laboratory and field settings has improved our knowledge of the effects of ionizing radiation on the environment. However, the results from such studies sometimes appear contradictory and there is disagreement about the implications for risk assessment. The Symposium discussions therefore focused on issues that might lead to different interpretations of the results, such as laboratory versus field approaches, organism versus population and ecosystemic inference strategies, dose estimation approaches and their significance under chronic exposure conditions. The participating scientists, from across the spectrum of disciplines and research areas, extending also beyond the traditional radioecology community, successfully developed a constructive spirit directed at understanding discrepancies. From the discussions, the group has derived seven consensus statements related to environmental protection against radiation, which are supplemented with some recommendations. Each of these statements is contextualized and discussed in view of contributing to the orientation and integration of future research, the results of which should yield better consensus on the ecological impact of radiation and consolidate suitable approaches for efficient radiological protection of the environment. - Highlights: • IUR built better scientific consensus on the ecological effects of radiation. • Laboratory versus field approaches have been addressed. • Organism versus

  3. Analysis of radiation and chemical factors which define the ecological situation of environment

    International Nuclear Information System (INIS)

    Trofimenko, A.P.

    1996-01-01

    A new method of large information set statistical analysis is proposed. It permits to define the main directions of work in a given field in the world or in a particular country, to find the most important investigated problems and to evaluate the role each of them quantitatively, as well as to study the dynamics of work development in time, the methods of research used, the centres in which this research is mostly developed, authors of publications etc. Statistical analysis may be supplemented with subject analysis of selected publications. Main factors which influence on different environment components and on public health are presented as an example of this method use, and the role of radiation and chemical factors is evaluated. 18 refs., 6 tab

  4. Lighting considerations in controlled environments for nonphotosynthetic plant responses to blue and ultraviolet radiation

    Science.gov (United States)

    Caldwell, M. M.; Flint, S. D.

    1994-01-01

    This essay will consider both physical and photobiological aspects of controlled environment lighting in the spectral region beginning in the blue and taken to the normal limit of the solar spectrum in the ultraviolet. The primary emphasis is directed to questions of plant response to sunlight. Measurement and computations used in radiation dosimetry in this part of the spectrum are also briefly treated. Because of interest in the ozone depletion problem, there has been some activity in plant UV-B research and there are several recent reviews available. Some aspects of growth chamber lighting as it relates to UV-B research were covered earlier. Apart from work related to the blue/UV-A receptor, less attention has been given to UV-A responses.

  5. Nuclear Radiation Fields on the Mars Surface: Risk Analysis for Long-term Living Environment

    Science.gov (United States)

    Anderson, Brooke M.; Clowdsley, Martha S.; Qualls, Garry D.; Nealy, John E.

    2005-01-01

    Mars, our nearest planet outward from the sun, has been targeted for several decades as a prospective site for expanded human habitation. Background space radiation exposures on Mars are expected to be orders of magnitude higher than on Earth. Recent risk analysis procedures based on detailed dosimetric techniques applicable to sensitive human organs have been developed along with experimental data regarding cell mutation rates resulting from exposures to a broad range of particle types and energy spectra. In this context, simulated exposure and subsequent risk for humans in residence on Mars are examined. A conceptual habitat structure, CAD-modeled with duly considered inherent shielding properties, has been implemented. Body self-shielding is evaluated using NASA standard computerized male and female models. The background environment is taken to consist not only of exposure from incident cosmic ray ions and their secondaries, but also include the contribution from secondary neutron fields produced in the tenuous atmosphere and the underlying regolith.

  6. Lighting considerations in controlled environments for nonphotosynthetic plant responses to blue and ultraviolet radiation

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, M.M.; Flint, S.D. [Utah State Univ., Logan, UT (United States)

    1994-12-31

    This essay will consider both physical and photobiological aspects of controlled environment lighting in the spectral region beginning in the blue and taken to the normal limit of the solar spectrum in the ultraviolet. The primary emphasis is directed to questions of plant response to sunlight. Measurement and computations used in radiation dosimetry in this part of the spectrum are also briefly treated. Because of interest in the ozone depletion problem, there has been some activity in plant UV-B research and there are several recent reviews available. Some aspects of growth chamber lighting as it relates to UV-B research were covered earlier. Apart from work related to the blue/UV-A receptor, less attention has been given to UV-A responses.

  7. Habitability in High Radiation Environments: The Case for Gaia at Europa

    Science.gov (United States)

    Cooper, J. F.

    2004-12-01

    In the paper of Cooper et al. (2001) we concluded, in relation to our work on magnetospheric irradiation of Europa and the other icy galilean moons of Jupiter, that 'icy satellites with significant heat, irradiation, and subsurface water resources may provide common abodes for life throughout the universe'. This expanded the original proposal of Chyba (2000) and his later works that radiolytic production of oxidants and simple hydrocarbons on Europa's icy surface could support evolution and survival of life within a Europan subsurface ocean. In the general case of icy planets and moons the radiation environment does not have to interact directly with the surface but could also provide energy for life through radiation-induced chemistry in thick atmospheres chemically coupled to icy surfaces with hydrocarbon reservoirs as on Titan. The Gaia model for Earth implies that the entire planet operates with atmospheric, geologic, and geochemical processes conducive to life. Essential requirements for Gaia are an oxidizing atmospheric environment at planetary surfaces, where oxidants like molecular oxygen are produced by radiation processes (mediated by photosynthetic chemistry on Earth but more directly produced by radiolysis on Europa), reservoirs of liquid water and hydrocarbons on or below the surface, other reduced materials in the interior, and geologic processes which drive chemical exchange between the chemically oxidized surface and reduced interior environments. At Europa a thin oxygen atmosphere is observed and arises from magnetospheric interaction, and there is much evidence for active resurfacing likely related to solid-state convection and diapiric processes within a thick crust of soft ice overlying a liquid ocean. These processes on Europa are analogous to that of the tectonic conveyer belt that continually recycles carbon, oxygen, and other essential materials for life between the atmosphere, surface, and interior on Earth. The ice crust at Europa could be

  8. DNA Radiation Environments Program: Fall 1989 2-meter box experiments and analysis

    International Nuclear Information System (INIS)

    Santoro, R.T.

    1991-05-01

    This effort, sponsored by the Defense Nuclear Agency under the Radiation Environments Program, was carried out to obtain measured data for benchmarking MASH, the Monte Carlo Adjoint Code System. MASH was developed to replace the Vehicle Code System, VCS, that has been used by the Department of Defense and NATO for calculating neutron and gamma-ray radiation fields and shielding protection factors inside armored vehicles and structures from nuclear weapon radiation. Free-field data were obtained at distances of 170- and 400-meters from the APR while in-box measurements were made at 400 meters only. The box, included to obtain neutron and gamma-ray reduction factors, was a 2-meter cube configuration having 0.1016-m-thick steel walls. Calculated data were obtained using MASH by analysts from the Oak Ridge National Laboratory and Science Applications International Corporation. Calculated (C) results were compared with experimental (E) data in terms of C/E ratios. Free-field and in-box neutron kerma generally agreed within ±20%, although some C/E comparisons fell outside this range depending upon the detector against which the calculated data were compared. For those cases where the C/E ratio is marginal or unacceptable, problems in the detector systems were acknowledged to be principal cause of the discrepancy. Generally poor agreement (∼25-35%) was achieved among the C/E ratios for the free-field gamma-ray kerma at the 170- and 400-m locations while excellent (10%, or better) C/E values were obtained for the in-box conditions. The discrepancy for the free-field comparison was attributed to the failure by the analysts to include a tree line adjacent to the measurement site in the calculational geometry. C/E values for the neutron and gamma-ray reduction factors ranged from 1% to 23% depending on the detector. 4 refs., 2 figs., 14 tabs

  9. Beam test results of CMS RPCs at high eta region under high-radiation environment

    CERN Document Server

    Park, S; Bahk, S Y; Hong, B; Hong, S J; Kang, D H; Kang, T I; Kim, T J; Kim, Y J; Kim, Y U; Koo, D G; Lee, H W; Lee, K S; Lee, S J; Lim, J K; Moon, D H; Nam, S K; Oh, J K; Park, W J; Rhee, J T; Ryu, M S; Shim, H H; Sim, K S

    2004-01-01

    The Compact Muon Solenoid (CMS) forward resistivity plate chambers (RPCs) at the high eta region must be operated in presence of a radiation-induced rate as high as 1 kHz/cm**2. It is still unknown if the RPCs coated with linseed oil can be operated under such a high- radiation environment over the lifetime of CMS. Non-oiled RPCs may be one of the options since phenolic or melamine-coated bakelite is chemically stabler than linseed oil. We have constructed oiled and non-oiled RPCs at the high eta region of CMS using phenolic bakelite and tested them in the Gamma Irradiation Facility at CERN. While both RPCs show the same characteristics in the efficiency and the strip multiplicity, the non-oiled RPC generates an intrinsic noise rate of 50 Hz/cm**2, compared to only 5 Hz/cm**2 for the oiled RPC, both at 10.0kV which is about 100 V above the 95% knee of the efficiency curve.

  10. Beam test results of CMS RPCs at high eta region under high-radiation environment

    International Nuclear Information System (INIS)

    Park, S.; Ahn, S.H.; Bahk, S.Y.; Hong, B.; Hong, S.J.; Kang, D.H.; Kang, T.I.; Kim, T.J.; Kim, Y.J.; Kim, Y.U.; Koo, D.G.; Lee, H.W.; Lee, K.S.; Lee, S.J.; Lim, J.K.; Moon, D.H.; Nam, S.K.; Oh, J.K.; Park, W.J.; Rhee, J.T.; Ryu, M.S.; Shim, H.H.; Sim, K.S.

    2004-01-01

    The Compact Muon Solenoid (CMS) forward resistivity plate chambers (RPCs) at the high eta region must be operated in presence of a radiation-induced rate as high as 1kHz/cm2. It is still unknown if the RPCs coated with linseed oil can be operated under such a high-radiation environment over the lifetime of CMS. Non-oiled RPCs may be one of the options since phenolic or melamine-coated bakelite is chemically stabler than linseed oil. We have constructed oiled and non-oiled RPCs at the high eta region of CMS using phenolic bakelite and tested them in the Gamma Irradiation Facility at CERN. While both RPCs show the same characteristics in the efficiency and the strip multiplicity, the non-oiled RPC generates an intrinsic noise rate of 50Hz/cm2, compared to only 5Hz/cm2 for the oiled RPC, both at 10.0kV which is about 100V above the 95% knee of the efficiency curve

  11. Study of radiation environment at the Chernobyl' APP after the accident

    International Nuclear Information System (INIS)

    Teplov, P.V.; Shaposhnikov, B.G.; Groshev, I.M.

    1989-01-01

    The results of investigation of June-December 1986 radiation environment (RE) in the area of 30-km around the Chernobyl' APP after the accident are analyzed. Long-term sampling locations data presented a picture of the entire contaminated 30-km area including a major part of populated areas, technical areas, water sources and their sediments, air, biosphere etc. During first 20-30 days after the accident RE was contributed by relatively short-lived fission products ( 131 J, 140 La). A month later radiation dose rates were indicated for 75 Zr and 95 Nb. In 1.5-2 years radioactivity and dose intensity became dependent for a while on 134 Cs and 106 Ru, and in 3-4 years the long-lived 90 Sr, 137 Cs and 239 Pu will mainly contribute into radioactivity. Such picture is characteristic of the entire 30 km area. However, there are some deviations. Much attention has been paid to the state of air outside and inside the rooms of the reactor blocks scheduled for start-up, as well as the state of ponds intended for reactor cooling. 16 figs., 36 tabs

  12. The cellular environment in computer simulations of radiation-induced damage to DNA

    International Nuclear Information System (INIS)

    Moiseenko, V.V.; Hamm, R.N.; Waker, A.J.; Prestwich, W.V.

    1988-01-01

    Radiation-induced DNA single- and double-strand breaks were modeled for 660 keV photon radiation and scavenger capacity mimicking the cellular environment. Atomistic representation of DNA in B form with a first hydration shell was utilized to model direct and indirect damage. Monte Carlo generated electron tracks were used to model energy deposition in matter and to derive initial spatial distributions of species which appear in the medium following radiolysis. Diffusion of species was followed with time, and their reactions with DNA and each other were modeled in an encounter-controlled manner. Three methods to account for hydroxyl radical diffusion in cellular environment were tested: assumed exponential survival, time-limited modeling and modeling of reactions between hydroxyl radicals and scavengers in an encounter-controlled manner. Although the method based on modeling scavenging in an encounter-controlled manner is more precise, it requires substantially more computer resources than either the exponential or time-limiting method. Scavenger concentrations of 0.5 and 0.15 M were considered using exponential and encounter-controlled methods with reaction rate set at 3x10 9 dm 3 mol -1 s-1. Diffusion length and strand break yields, predicted by these two methods for the same scavenger molarity, were different by 20%-30%. The method based on limiting time of chemistry follow-up to 10 -9 s leads to DNA damage and radical diffusion estimates similar to 0.5 M scavenger concentration in the other two methods. The difference observed in predictions made by the methods considered could be tolerated in computer simulations of DNA damage. (author)

  13. Interactive visual intervention planning in particle accelerator environments with ionizing radiation

    CERN Document Server

    Fabry, Thomas

    Radiation is omnipresent. It has many interesting applications: in medicine, where it allows curing and diagnosing patients; in communication, where modern communication systems make use of electromagnetic radiation; and in science, where it is used to discover the structure of materials; to name a few. Physically, radiation is a process in which particles or waves travel through any kind of material, usually air. Radiation can be very energetic, in which case it can break the atoms of ordinary matter (ionization). If this is the case, radiation is called ionizing. It is known that ionizing radiation can be far more harmful to living beings than non-ionizing radiation. In this dissertation, we are concerned with ionizing radiation. Naturally occurring ionizing radiation in the form of radioactivity is a most natural phenomenon. Almost everything is radioactive: there is radiation emerging from the soil, it is in the air, and the whole planet is constantly undergoing streams of energetic cosmic radiation. Sinc...

  14. Study of radiosensitivity and antioxidant-oxidant state in workers exposed to ionizing radiation in the hospital environment

    International Nuclear Information System (INIS)

    Sebastià, N.; Rodrigo, R.; Hervás, D.; Olivares-González, L; Óscar Alonso, O.; Marti, L.; Jambrina, E.; Sarrias, A.; Pérez-Calatayud, J.; García, T.; Gras, P.; Villaescusa, J.I.; Soriano, J.M.; León, Z.; Montoro, A.

    2014-01-01

    Prevention and protection of workers exposed to ionizing radiation is an objective of particular importance from the occupational health and safety point of view. This study establishes a technique for the evaluation of the individual radiosensibility of workers exposed to ionizing radiation in the Hospital environment using the cytogenetic biomarker known as the G2 –Test. In addition, using various oxidative stress biomarkers and antioxidant capacity, we evaluate the antioxidant-oxidant state of these workers. Both biomarkers could be established as additional tools in the medical control of workers exposed to ionizing radiation. [es

  15. Review of problems and methods for radiation risk assessment in the environment of a nuclear power plant

    International Nuclear Information System (INIS)

    Grgic, M.

    1966-01-01

    Radiation impact on the nuclear power plant environment is a very important problem which has to be solved during design and construction. Damage that could be caused by release of radioactive material into the environment should be estimated and the magnitude of nuclear and radiation risk of the power plant should be evaluated. In general the accuracy of estimation is rather poor due to statistical fluctuations of the conditions which influence radioactivity expansion in the environment, especially in the air. Different uncertainties and unresolved problems influence the inaccuracy. Since any real risk should be extremely small compared to potential risk i.e. risk induced by nuclear power plant without any safety measures, even inaccurate estimations are very useful. Method for environmental radiation risk assessment is based on relatively simple models of radiation expansion in the environment and in the air. These models are theoretically solved but they are based on relatively limited number of experimental data. Assessment of the radiation effects on the population health and mortality is an important problem [sl

  16. Establishing a Robotic, LEO-to-GEO Satellite Servicing Infrastructure as an Economic Foundation for Exploration

    Science.gov (United States)

    Horsham, Gary A. P.; Schmidt, George R.; Gilland, James H.

    2010-01-01

    The strategy for accomplishing civilian exploration goals and objectives is in the process of a fundamental shift towards a potential new approach called Flexible Path. This paper suggests that a government-industry or public-private partnership in the commercial development of low Earth orbit to geostationary orbit (LEO-to-GEO (LTG)) space, following or in parallel with the commercialization of Earth-to-LEO and International Space Station (ISS) operations, could serve as a necessary, logical step that can be incorporated into the flexible path approach. A LTG satellite-servicing infrastructure and architecture concept is discussed within this new strategic context. The concept consists of a space harbor that serves as a transport facility for a fleet of specialized, fully- or semi-autonomous robotic servicing spacecraft. The baseline, conceptual system architecture is composed of a space harbor equipped with specialized servicer spacecraft; a satellite command, communication, and control system; a parts station; a fuel station or depot; and a fuel/parts replenishment transport. The commercial servicer fleet would consist of several types of spacecraft, each designed with specialized robotic manipulation subsystems to provide services such as refueling, upgrade, repair, inspection, relocation, and removal. The space harbor is conceptualized as an ISS-type, octagonal truss structure equipped with radiation tolerant subsystems. This space harbor would be primarily capable of serving as an operational platform for various commercially owned and operated servicer spacecraft positioned and docked symmetrically on four of the eight sides. Several aspects of this concept are discussed, such as: system-level feasibility in terms of ISS-truss-type infrastructure and subsystems emplacement and maintenance between LEO and GEO; infrastructure components assembly in LEO, derived from ISS assembly experience, and transfer to various higher orbital locations; the evolving Earth

  17. Radiation resistance of bacterial populations, isolated from the environment of the radiation sterilization plant type JS-6900, Debrecen

    International Nuclear Information System (INIS)

    Gazso, L.; Igali, S.; Daroczy, E.

    1978-01-01

    The radiation resistance of bacterial populations isolated from the air of an industrial sterilization plant loaded with an activity of 250000 Ci was investigated before loading and a year after loading with 60 Co. The mean D 10 value of the 23 strains isolated before loading was 73 krad with a maximum of 173 krad. The mean D 10 value of the 26 strains isolated a year after loading was 32 krad with a maximum of 156 krad. It was not possible to detect any increase in radiation resistance of bacterial populations isolated from the irradiation room after one year of running radiation sterilization of disposable medical supplies. (author)

  18. Nickel metal hydride LEO cycle testing

    Science.gov (United States)

    Lowery, Eric

    1995-01-01

    The George C. Marshall Space Flight Center is working to characterize aerospace AB5 Nickel Metal Hydride (NiMH) cells. The cells are being evaluated in terms of storage, low earth orbit (LEO) cycling, and response to parametric testing (high rate charge and discharge, charge retention, pulse current ability, etc.). Cells manufactured by Eagle Picher are the subjects of the evaluation. There is speculation that NiMH cells may become direct replacements for current Nickel Cadmium cells in the near future.

  19. Contribution to the study of the radiation environment in Antananarivo: Assessment of the Exposure of the Public to the Telluric X and Gamma Radiations and the Radon

    International Nuclear Information System (INIS)

    Ravelomanantsoa, S.D.

    2001-01-01

    The radioactivity represents among indicators of state of the environment because the man is exposed to ionizing radiations of permanent way. The knowledge of the different components of this natural radioactivity to which the humanity has always been exposed proves out to be necessary. The state of places of this radioactive environment deserves to be made for Antananarivo, the city the populated more of Madagascar. The present thesis on the 'Assessment of the Exposure of the Public to the Telluric X and Gamma Radiations and the Radon to Antananarivo' contributes to the survey of the Radioactive Environment. It is the synthesis of results of all works done in the setting of a research project that lasted three years, works constituted by more of about hundred coming down on land and by the analysis in laboratory of about hundred samples.The radioactive radiation detection, the radioactive substance characterization in the environment and the assessment of dose exposure has been done by the global counting of the X and gamma ambient radiations, of spectrometric measures on land and in laboratory and by alpha, X and gamma dosimetric measures, to the free air and inside of buildings, the day and the night. The gotten results served basis to three communications made to the National Academy of Arts, of Letters and Science, Tsimbazaza, Antananarivo in June 1998, in May 1999 and in December 2000. An evaluation of the contribution of the telluric X and gamma rays and of the radon in the yearly efficient average dose owed to natural radiation sources finishes the state of places that is going to lead to the unpublished values. [fr

  20. Leo P: An Unquenched Very Low-Mass Galaxy

    OpenAIRE

    McQuinn, Kristen B. W.; Skillman, Evan D.; Dolphin, Andrew; Cannon, John M.; Salzer, John J.; Rhode, Katherine L.; Adams, Elizabeth A. K.; Berg, Danielle; Giovanelli, Riccardo; Girardi, Léo; Haynes, Martha P.

    2015-01-01

    Leo P is a low-luminosity dwarf galaxy discovered through the blind HI Arecibo Legacy Fast ALFA (ALFALFA) survey. The HI and follow-up optical observations have shown that Leo P is a gas-rich dwarf galaxy with active star formation, an underlying older population, and an extremely low oxygen abundance. We have obtained optical imaging with the Hubble Space Telescope to two magnitudes below the red clump in order to study the evolution of Leo P. We refine the distance measurement to Leo P to b...

  1. Optimal trajectories for aeroassisted, noncoplanar orbital transfer. II - LEO-to-LEO transfer

    Science.gov (United States)

    Miele, A.; Mease, K. D.; Lee, W. Y.

    1987-01-01

    Both classical and minimax problems of optimal control arising in the study of noncoplanar, aeroassisted orbital transfer are considered and are illustrated with the example of LEO-to-LEO transfer. Trajectory control is achieved by modulation of the lift coefficient and the angle of bank. Problems considered include the minimization of the energy required for orbital transfer, maximization of the flight time during the atmospheric portion of the trajectory, and minimization of the peak heating rate. The near-grazing solution is found to be a good compromise between energy and heating requirements.

  2. Leo Satellite Communication through a LEO Constellation using TCP/IP Over ATM

    Science.gov (United States)

    Foore, Lawrence R.; Konangi, Vijay K.; Wallett, Thomas M.

    1999-01-01

    The simulated performance characteristics for communication between a terrestrial client and a Low Earth Orbit (LEO) satellite server are presented. The client and server nodes consist of a Transmission Control Protocol /Internet Protocol (TCP/IP) over ATM configuration. The ATM cells from the client or the server are transmitted to a gateway, packaged with some header information and transferred to a commercial LEO satellite constellation. These cells are then routed through the constellation to a gateway on the globe that allows the client/server communication to take place. Unspecified Bit Rate (UBR) is specified as the quality of service (QoS). Various data rates are considered.

  3. Lack of correlation of desiccation and radiation tolerance in microorganisms from diverse extreme environments tested under anoxic conditions.

    Science.gov (United States)

    Beblo-Vranesevic, Kristina; Bohmeier, Maria; Perras, Alexandra K; Schwendner, Petra; Rabbow, Elke; Moissl-Eichinger, Christine; Cockell, Charles S; Vannier, Pauline; Marteinsson, Viggo T; Monaghan, Euan P; Ehrenfreund, Pascale; Garcia-Descalzo, Laura; Gómez, Felipe; Malki, Moustafa; Amils, Ricardo; Gaboyer, Frédéric; Westall, Frances; Cabezas, Patricia; Walter, Nicolas; Rettberg, Petra

    2018-03-01

    Four facultative anaerobic and two obligate anaerobic bacteria were isolated from extreme environments (deep subsurface halite mine, sulfidic anoxic spring, mineral-rich river) in the frame MASE (Mars Analogues for Space Exploration) project. The isolates were investigated under anoxic conditions for their survivability after desiccation up to 6 months and their tolerance to ionizing radiation up to 3000 Gy. The results indicated that tolerances to both stresses are strain-specific features. Yersinia intermedia MASE-LG-1 showed a high desiccation tolerance but its radiation tolerance was very low. The most radiation-tolerant strains were Buttiauxella sp. MASE-IM-9 and Halanaerobium sp. MASE-BB-1. In both cases, cultivable cells were detectable after an exposure to 3 kGy of ionizing radiation, but cells only survived desiccation for 90 and 30 days, respectively. Although a correlation between desiccation and ionizing radiation resistance has been hypothesized for some aerobic microorganisms, our data showed that there was no correlation between tolerance to desiccation and ionizing radiation, suggesting that the physiological basis of both forms of tolerances is not necessarily linked. In addition, these results indicated that facultative and obligate anaerobic organisms living in extreme environments possess varied species-specific tolerances to extremes.

  4. The expression revealing variation trend about radiation resistance of aromatic polymers serving in nuclear environment over absorbed dose

    Science.gov (United States)

    Lu, Shuangying; Hu, Huasi; Hu, Guang; Liu, Bin

    2015-03-01

    For polymeric materials applied in nuclear environment, the macroscopic properties usually remain unchanged after irradiation for several years or decades up to a threshold dose at which the deterioration of materials begins to take place. In this paper, the general radiation response of aromatic polymers is firstly reviewed and discussed. Then percolation theory is employed innovatively to elucidate the critical phenomenon over the service life for polymeric materials with high radiation resistance. For a better quantitative evaluation, a novel two-parameter radiation resistance model is proposed by the method of analogy between two nuclear-related phenomena. Six epoxy systems are employed from the published literatures to verify the novel model and the result shows that it is reliable and helpful in not only estimating the radiation damage over the service period but also multi-objective optimum design of polymeric materials.

  5. Preliminary results of the preoperational radiation survey carried out in the environs of Domiasiat, Meghalaya, India, using TL dosimetric techniques

    International Nuclear Information System (INIS)

    Chougaonkar, M.P.; Khan, A.H.; Puranik, V.D.; Walling, I.M.; Hoda, S.Q.

    2004-01-01

    Preoperational survey of gamma radiation levels, using thermoluminescent dosimeters (TLDs), carried out in the environs of Domiasiat, Meghalaya, where natural uranium deposits have been found, are discussed in this paper. Two gamma radiation surveys, of about two months duration each, were carried out in the region using TLDs. The natural background gamma radiation levels, in the region under survey, at 1 m height from the ground were found to be 0.17 ± 0.07 μGy h -l in the areas where the mining of uranium is proposed while the surrounding areas showed 0.16 ± 0.07 μGy h -l . This data will be useful, after the operations of uranium mining starts, to assess the impact of the operations on the radiation levels in the surrounding areas. (author)

  6. Radiation Beamline Testbeds for the Simulation of Planetary and Spacecraft Environments for Human and Robotic Mission Risk Assessment

    Science.gov (United States)

    Wilkins, Richard

    2010-01-01

    The Center for Radiation Engineering and Science for Space Exploration (CRESSE) at Prairie View A&M University, Prairie View, Texas, USA, is establishing an integrated, multi-disciplinary research program on the scientific and engineering challenges faced by NASA and the international space community caused by space radiation. CRESSE focuses on space radiation research directly applicable to astronaut health and safety during future long term, deep space missions, including Martian, lunar, and other planetary body missions beyond low earth orbit. The research approach will consist of experimental and theoretical radiation modeling studies utilizing particle accelerator facilities including: 1. NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory; 2. Proton Synchrotron at Loma Linda University Medical Center; and 3. Los Alamos Neutron Science Center (LANSCE) at Los Alamos National Laboratory. Specifically, CRESSE investigators are designing, developing, and building experimental test beds that simulate the lunar and Martian radiation environments for experiments focused on risk assessment for astronauts and instrumentation. The testbeds have been designated the Bioastronautics Experimental Research Testbeds for Environmental Radiation Nostrum Investigations and Education (BERT and ERNIE). The designs of BERT and ERNIE will allow for a high degree of flexibility and adaptability to modify experimental configurations to simulate planetary surface environments, planetary habitats, and spacecraft interiors. In the nominal configuration, BERT and ERIE will consist of a set of experimental zones that will simulate the planetary atmosphere (Solid CO2 in the case of the Martian surface.), the planetary surface, and sub-surface regions. These experimental zones can be used for dosimetry, shielding, biological, and electronic effects radiation studies in support of space exploration missions. BERT and ERNIE are designed to be compatible with the

  7. Radiation beamline testbeds for the simulation of planetary and spacecraft environments for human and robotic mission risk assessment

    Science.gov (United States)

    Wilkins, Richard

    The Center for Radiation Engineering and Science for Space Exploration (CRESSE) at Prairie View A&M University, Prairie View, Texas, USA, is establishing an integrated, multi-disciplinary research program on the scientific and engineering challenges faced by NASA and the inter-national space community caused by space radiation. CRESSE focuses on space radiation research directly applicable to astronaut health and safety during future long term, deep space missions, including Martian, lunar, and other planetary body missions beyond low earth orbit. The research approach will consist of experimental and theoretical radiation modeling studies utilizing particle accelerator facilities including: 1. NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory; 2. Proton Synchrotron at Loma Linda University Med-ical Center; and 3. Los Alamos Neutron Science Center (LANSCE) at Los Alamos National Laboratory. Specifically, CRESSE investigators are designing, developing, and building experimental test beds that simulate the lunar and Martian radiation environments for experiments focused on risk assessment for astronauts and instrumentation. The testbeds have been designated the Bioastronautics Experimental Research Testbeds for Environmental Radiation Nostrum Investigations and Education (BERT and ERNIE). The designs of BERT and ERNIE will allow for a high degree of flexibility and adaptability to modify experimental configurations to simulate planetary surface environments, planetary habitats, and spacecraft interiors. In the nominal configuration, BERT and ERIE will consist of a set of experimental zones that will simulate the planetary atmosphere (Solid CO2 in the case of the Martian surface.), the planetary surface, and sub-surface regions. These experimental zones can be used for dosimetry, shielding, biological, and electronic effects radiation studies in support of space exploration missions. BERT and ERNIE are designed to be compatible with the

  8. OPEN RADIATION: a collaborative project for radioactivity measurement in the environment by the public

    Science.gov (United States)

    Bottollier-Depois, Jean-François; Allain, E.; Baumont, G.; Berthelot, N.; Clairand, I.; Couvez, C.; Darley, G.; Henry, B.; Jolivet, T.; Laroche, P.; Lebau-Livé, A.; Lejeune, V.; Miss, J.; Monange, W.; Quéinnec, F.; Richet, Y.; Simon, C.; Trompier, F.; Vayron, F.

    2017-09-01

    After the Fukushima accident, initiatives emerged from the public to carry out themselves measurements of the radioactivity in the environment with various devices, among which smartphones, and to share data and experiences through collaborative tools and social networks. Such measurements have two major interests, on the one hand, to enable each individual of the public to assess his own risk regarding the radioactivity and, on the other hand, to provide "real time" data from the field at various locations, especially in the early phase of an emergency situation, which could be very useful for the emergency management. The objective of the OPENRADIATION project is to offer to the public the opportunity to be an actor for measurements of the radioactivity in the environment using connected dosimetric applications on smartphones. The challenge is to operate such a system on a sustainable basis in peaceful time and be useful in case of emergency. In "peaceful situation", this project is based on a collaborative approach with the aim to get complementary data to the existing ones, to consolidate the radiation background, to generate alerts in case of problem and to provide education & training and enhanced pedagogical approaches for a clear understanding of measures for the public. In case of emergency situation, data will be available "spontaneously" from the field in "real time" providing an opportunity for the emergency management and the communication with the public. … The practical objective is i) to develop a website centralising data from various systems/dosimeters, providing dose maps with raw and filtered data and creating dedicated areas for specific initiatives and exchanges of data and ii) to develop a data acquisition protocol and a dosimetric application using a connected dosimeter with a bluetooth connection. This project is conducted within a partnership between organisms' representative of the scientific community and associations to create links

  9. Research on the Computer System to Monitor the Physiological Parameter under Nuclear Radiation Environment

    International Nuclear Information System (INIS)

    Wang Ji; Xie Shiyi; Ren Xiaoli; Shen Yuli

    2009-01-01

    In view of special monitoring equipment wiring complexity and not checking potential health risks currently. Methods To propose monitoring platform of automatic wearing physiology based on wireless sensor network (WSN), and nodes include multi-physiological parameter intelligent sensors such as respiration, ECG and position, movement, temperature of body. Network gateway completed the data remote transmission accurately by using GPRS communication mode. Researched simulation system developed network gateway by XT5 and nodes used punctate series sensors such as MICA2 and MICA2DOT of Crossbow Company. when experimenter wore the special monitoring the collected information of physiology and location was accurately transmitted to the monitoring point that was 500 kilometers away, thereafter terminal computer visually supervised the transmitted information of volunteers. The system stably operates at operating frequency 2.4 GHz bands, transmit power-5 dB, data rate 40 Kbps or so. The principial result shows: The located monitoring of real-time dynamic physiology was carried out for the system prototype worn on the supervisor's physical corresponding parts. The system is suitable for application in Nuclear Radiation Environment. (authors)

  10. Impact of LEO satellites on global GPS solutions

    Science.gov (United States)

    Rothacher, M.; Svehla, D.

    2003-04-01

    Already at present quite a few Low Earth Orbiting (LEO) satellites (SAC-C, CHAMP, JASON-1, GRACE-1 and GRACE-2) are equipped with one or more GPS receivers for precise orbit determination or other applications (atmospheric sounding, gravity field recovery, ...). This trend will continue in the near future (e.g., with the GOCE and COSMIC missions) and we will soon have an entire``constellation´´ of LEO satellites tracked by GPS at our disposal. In this contribution we study the impact of LEO GPS measurements (from a single LEO satellite or from a LEO constellation) on global GPS solutions, where GPS satellite orbits and clocks, Earth rotation parameters (ERPs), station coordinates and troposphere zenith delays are determined simultaneously. In order to assess the impact of the LEO GPS data on global IGS results, we perform a combined analysis of the space-borne and the ground-based GPS data. Such a combination may benefit on one hand from the differences between a ground station and a LEO, namely, (1) the different tracking geometry (coverage of isolated geographical areas by LEOs, rapidly changing geometry, ...); (2) that LEOs connect all ground stations within 1-2 hours; (3) that baselines between LEO and ground stations may be longer than station-station baselines; (4) that no tropospheric delays have to be estimated for LEOs; and (5) that LEOs orbit the Earth within the ionosphere and may therefore contribute to global ionosphere models. On the other hand we have to deal with difficult aspects of precise orbit determination for the LEOs: only if we succeed to obtain very accurate dynamic or reduced-dynamic orbits for the LEOs, we will have a chance to improve the global GPS results at all. We present first results concerning the influence of LEO data on GPS orbits, ERPs, site coordinates, and troposphere zenith delays using both, variance-covariance analyses based on simulated data and combined global solutions based on real CHAMP and JASON data and the data

  11. Effect of Gamma Radiation to the Content of Nutrition Duck Egg Environment Sample

    International Nuclear Information System (INIS)

    Sutjipto; Yohannes Sardjono

    2007-01-01

    The effect of gamma radiation dose of 0.7 kGy to the content of nutrition duck egg environment sample of Turi area, Bantul Yogyakarta has been studied. This research is conducted to determine the effect of gamma radiation 0.7 kGy to the nutrition duck egg which stored during 21 days. The grouped of some fresh duck egg sample to become 2 group. First group with 0 kGy (non irradiation) and the second group with 0.7 kGy dose. The irradiation sample was conducted at Kartini reactor Beamport. After the desired dose reached, the duck egg was lifted. Both irradiated and non irradiated duck egg then stored during 21 days. The research design used is Complete Block Random Device (RABL) with pattern factorial and restating as block. First factor : Dose of Irradiation (D) : D 1 = 0 kGy (non irradiation) and D 2 = 0.7 kGy. Second factors : stored time (P) : P 1 = 0 and day of P 2 = 21 days. The analysis of water content, total protein, dissolve protein, ash and fat was carried out. The research result shows that the gamma irradiation have no significant effect to the water content, total protein, dissolve protein, ash and fat both in white and also duck egg yolk for day of 0 (P> 0.05). For storage during 21 days, gamma radiation have significant effect to the water content, total protein, dissolve protein both in white and also duck egg yolk (P 0.05), because the irradiation process do not influence the availability of mineral in egg yolk and also have no significant effect to fat content (P> 0.05), because at the protein have compound which able to kill bacterium, so-called with lysozyme, besides high protein alkalinity which do not advantage growth of bacterium, so that during storage do not happened protein lipolysis by enzyme of lipase yielded by microbe. The effect of gamma radiation to the duck egg which stored during 21 days shows that the water content at white duck egg rising to 1.02 % wb, the protein total decreasing to 0.99 % db, the dissolve protein decreasing to 0

  12. Premar-2: a Monte Carlo code for radiative transport simulation in atmospheric environments

    Energy Technology Data Exchange (ETDEWEB)

    Cupini, E. [ENEA, Centro Ricerche Ezio Clementel, Bologna, (Italy). Dipt. Innovazione

    1999-07-01

    The peculiarities of the PREMAR-2 code, aimed at radiation transport Monte Carlo simulation in atmospheric environments in the infrared-ultraviolet frequency range, are described. With respect to the previously developed PREMAR code, besides plane multilayers, spherical multilayers and finite sequences of vertical layers, each one with its own atmospheric behaviour, are foreseen in the new code, together with the refraction phenomenon, so that long range, highly slanted paths can now be more faithfully taken into account. A zenithal angular dependence of the albedo coefficient has moreover been introduced. Lidar systems, with spatially independent source and telescope, are allowed again to be simulated, and, in this latest version of the code, sensitivity analyses to be performed. According to this last feasibility, consequences on radiation transport of small perturbations in physical components of the atmospheric environment may be analyze and the related effects on searched results estimated. The availability of a library of physical data (reaction coefficients, phase functions and refraction indexes) is required by the code, providing the essential features of the environment of interest needed of the Monte Carlo simulation. Variance reducing techniques have been enhanced in the Premar-2 code, by introducing, for instance, a local forced collision technique, especially apt to be used in Lidar system simulations. Encouraging comparisons between code and experimental results carried out at the Brasimone Centre of ENEA, have so far been obtained, even if further checks of the code are to be performed. [Italian] Nel presente rapporto vengono descritte le principali caratteristiche del codice di calcolo PREMAR-2, che esegue la simulazione Montecarlo del trasporto della radiazione elettromagnetica nell'atmosfera, nell'intervallo di frequenza che va dall'infrarosso all'ultravioletto. Rispetto al codice PREMAR precedentemente sviluppato, il codice

  13. Leo Kunnas : triibuline särk kuuli ei peata / Leo Kunnas ; interv. Jaanus Piirsalu

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    2005. aastal koalitsioonijõudude koosseisus Iraagis teeninud Leo Kunnas selgitab intervjuus, mida on Eesti kaitsevägi Iraagi missioonist õppinud, millist mõju on Eesti sõdurite osalemine välismissioonides avaldanud ühiskonnale, lisaks võrdleb Iraagi ja Afganistani missioone ning põhjendab, miks on palgaarmee loomise idee Eestis sõjaliselt mitterelevantne

  14. Mitigating the Effects of the Space Radiation Environment: A Novel Approach of Using Graded-Z Materials

    Science.gov (United States)

    Atwell, William; Rojdev, Kristina; Aghara, Sukesh; Sriprisan, Sirikul

    2013-01-01

    In this paper we present a novel space radiation shielding approach using various material lay-ups, called "Graded-Z" shielding, which could optimize cost, weight, and safety while mitigating the radiation exposures from the trapped radiation and solar proton environments, as well as the galactic cosmic radiation (GCR) environment, to humans and electronics. In addition, a validation and verification (V&V) was performed using two different high energy particle transport/dose codes (MCNPX & HZETRN). Inherently, we know that materials having high-hydrogen content are very good space radiation shielding materials. Graded-Z material lay-ups are very good trapped electron mitigators for medium earth orbit (MEO) and geostationary earth orbit (GEO). In addition, secondary particles, namely neutrons, are produced as the primary particles penetrate a spacecraft, which can have deleterious effects to both humans and electronics. The use of "dopants," such as beryllium, boron, and lithium, impregnated in other shielding materials provides a means of absorbing the secondary neutrons. Several examples of optimized Graded-Z shielding layups that include the use of composite materials are presented and discussed in detail. This parametric shielding study is an extension of some earlier pioneering work we (William Atwell and Kristina Rojdev) performed in 20041 and 20092.

  15. Petróleo, Royalties e Pobreza

    Directory of Open Access Journals (Sweden)

    Gicélia Mendes da Silva

    2009-08-01

    Full Text Available A exploração do petróleo se constitui num elemento significativo para a economia sergipana. A contradição existente entre o subsolo rico e a população pobre levanta indagações a respeito da gestão destes recursos e as condições de vida da população. Tais condições, aliadas à entrada de novos atores na exploração do petróleo em Sergipe e à gestão dos recursos advindos da exploração, vêm incutindo relações peculiares à política neoliberal na região e em Sergipe. O estudo foi desenvolvido a partir da análise e cruzamento de informações disponíveis na Agência Nacional do Petróleo (ANP, Instituto Brasileiro de Geografia e Estatística (IBGE, Tribunal de Contas da União (TCU e PETROBRAS, dentre outros setores. A carência de políticas sociais que ofereçam às populações condições de inserção nas questões política, econômica e social da região produtora de petróleo tem impedido o desenvolvimento efetivo e mudança no padrão de vida das populações, evidenciando a incoerência entre os altos valores depositados nos cofres públicos municipais decorrentes dos royalties e os elevados índices de pobreza apresentados na região. Tal constatação reforça a ideia de que as políticas públicas devem primar pela redução da desigualdade a partir da gestão responsável dos recursos públicos.

  16. On protection of freedom's solar dynamic radiator from the orbital debris environment. Part 2

    International Nuclear Information System (INIS)

    Rhatigan, J.L.

    1992-01-01

    In this paper, recent progress to better understand the environmental threat of micrometeoroid and space debris to the solar dynamic radiator for the Space Station Freedom power system is reported. The objective was to define a design which would perform to survivability requirements over the expected lifetime of the radiator. A previous paper described the approach developed to assess on-orbit survivability of the solar dynamic radiator due to micrometeoroid and space debris impacts. Preliminary analyses were presented to quantify the solar dynamic radiator survivability. These included the type of particle and particle population expected to defeat the radiator bumpering. Results of preliminary hypervelocity impact (HVI) testing performed on radiator panel samples were also presented. This paper presents results of a more extensive test program undertaken to further define the response of the solar dynamic radiator to HVI. Tests were conducted on representative radiator panels (under ambient, nonoperating conditions) over a range of particle size, particle density, impact angle, and impact velocity. Target parameters were also varied. Data indicate that analytical penetration predictions are conservative (i.e., pessimistic) for the specific configuration of the solar dynamic radiator. Test results are used to define more rigorously the solar dynamic radiator reliability with respect to HVI. Test data, analyses, and survivability results are presented

  17. Viiv enne kojuminekut / Leo Kunnas ; interv. Helen Arak

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kaitsejõudude Peastaabi operatiivosakonna ülem kolonelleitnant Leo Kunnas oma perekonnast, lapsepõlvekodust Põlvamaal ja praegusest elamisest Tallinnas, missioonil viibivate sõjaväelaste probleemidest ning eluolust Iraagis. Lisa: Katkend Leo Kunnase raamatust "Viiv pikas sõjas"

  18. Introducing Leo LT - the "three-headed lion"

    Index Scriptorium Estoniae

    2008-01-01

    Leedu valitsus kiitis heaks seaduseparandused, mille tulemusena saab võtta tuumajaama ehitaja, investeerimis- ja energiafirma Leo LT strateegilise tähtsusega firmade hulka. Kui parlament valitsuse ettepanekud heaks kiidab, saab riik 61,7% Leo LT ja 38,3% NDX Energija aktsiatest

  19. Assessment of radiation impact on the environment components while preparing for construction site of centralized storage facility for spent nuclear fuel (CSSNF)

    International Nuclear Information System (INIS)

    Pavlovs'kij, L.Yi.; Gorodets'kij, D.V.; Syizov, A.O.; Kholodyuk, A.O.

    2016-01-01

    Predictive assessment of radiation impacts on the air environment, soil cover, staff, which is located in a residential area, staff of an adjacent to the CSSNF enterprises as a result of work to prepare the site for construction of CSSNF at the Chornobyl Exclusion Zone is presented. It is shown that radiation effects on components of the environment will not result in exceeding the reference levels of radiation safety

  20. Interactive visual intervention planning in particle accelerator environments with ionizing radiation

    International Nuclear Information System (INIS)

    Fabry, Thomas

    2014-01-01

    Radiation is omnipresent. It has many interesting applications: in medicine, where it allows curing and diagnosing patients; in communication, where modern communication systems make use of electromagnetic radiation; and in science, where it is used to discover the structure of materials; to name a few. Physically, radiation is a process in which particles or waves travel through any kind of material, usually air. Radiation can be very energetic, in which case it can break the atoms of ordinary matter (ionization). If this is the case, radiation is called ionizing. It is known that ionizing radiation can be far more harmful to living beings than non-ionizing radiation. In this dissertation, we are concerned with ionizing radiation. Naturally occurring ionizing radiation in the form of radioactivity is a most natural phenomenon. Almost everything is radioactive: there is radiation emerging from the soil, it is in the air, and the whole planet is constantly undergoing streams of energetic cosmic radiation. Since the beginning of the twentieth century, we are also able to artificially create radioactive matter. This has opened a lot of interesting technological opportunities, but has also given a tremendous responsibility to humanity, as the nuclear accidents in Chernobyl and Fukushima, and various accidents in the medical world have made clear. This has led to the elaboration of a radiological protection system. In practice, the radiological protection system is mostly implemented using a methodology that is indicated with the acronym ALARA: As Low As Reasonably Achievable. This methodology consists of justifying, optimizing and limiting the radiation dose received. This methodology is applied in conjunction with the legal limits. The word 'reasonably' means that the optimization of radiation exposure has to be seen in context. The optimization is constrained by the fact that the positive effects of an operation might surpass the negative effects caused by the

  1. The Diurnal Cycle of the Boundary Layer, Convection, Clouds, and Surface Radiation in a Coastal Monsoon Environment (Darwin Australia)

    Energy Technology Data Exchange (ETDEWEB)

    May, Peter T.; Long, Charles N.; Protat, Alain

    2012-08-01

    The diurnal variation of convection and associated cloud and radiative properties remains a significant issue in global NWP and climate models. This study analyzes observed diurnal variability of convection in a coastal monsoonal environment examining the interaction of convective rain clouds, their associated cloud properties, and the impact on the surface radiation and corresponding boundary layer structure during periods where convection is suppressed or active on the large scale. The analysis uses data from the Tropical Warm Pool International Cloud Experiment (TWP-ICE) as well as routine measurements from the Australian Bureau of Meteorology and the U.S. Department of Energy Atmospheric Radiation Measurement (ARM) program. Both active monsoonal and large-scale suppressed (buildup and break) conditions are examined and demonstrate that the diurnal variation of rainfall is much larger during the break periods and the spatial distribution of rainfall is very different between the monsoon and break regimes. During the active monsoon the total net radiative input to the surface is decreased by more than 3 times the amount than during the break regime - this total radiative cloud forcing is found to be dominated by the shortwave (SW) cloud effects because of the much larger optical thicknesses and persistence of long-lasting anvils and cirrus cloud decks associated with the monsoon regime. These differences in monsoon versus break surface radiative energy contribute to low-level air temperature differences in the boundary layer over the land surfaces.

  2. Improvement of the equivalent sphere model for better estimates of skin or eye dose in space radiation environments

    International Nuclear Information System (INIS)

    Lin, Z.W.

    2011-01-01

    It is often useful to get a quick estimate of the dose or dose equivalent of an organ, such as blood-forming organs, the eye or the skin, in a radiation field. Sometimes an equivalent sphere is used to represent the organ for this purpose. For space radiation environments, recently it has been shown that the equivalent sphere model does not work for the eye or the skin in solar particle event environments. In this study, we improve the representation of the eye and the skin using a two-component equivalent sphere model. Motivated by the two-peak structure of the body organ shielding distribution for the eye and the skin, we use an equivalent sphere with two radius parameters, for example a partial spherical shell of a smaller thickness over a proper fraction of the full solid angle combined with a concentric partial spherical shell of a larger thickness over the rest of the full solid angle, to represent the eye or the skin. We find that using an equivalent sphere with two radius parameters instead of one drastically improves the accuracy of the estimates of dose and dose equivalent in space radiation environments. For example, in solar particle event environments the average error in the estimate of the skin dose equivalent using an equivalent sphere with two radius parameters is about 8%, while the average error of the conventional equivalent sphere model using one radius parameter is around 100%.

  3. Environment

    DEFF Research Database (Denmark)

    Valentini, Chiara

    2017-01-01

    The term environment refers to the internal and external context in which organizations operate. For some scholars, environment is defined as an arrangement of political, economic, social and cultural factors existing in a given context that have an impact on organizational processes and structures....... For others, environment is a generic term describing a large variety of stakeholders and how these interact and act upon organizations. Organizations and their environment are mutually interdependent and organizational communications are highly affected by the environment. This entry examines the origin...... and development of organization-environment interdependence, the nature of the concept of environment and its relevance for communication scholarships and activities....

  4. A Radiation Hard Multi-Channel Digitizer ASIC for Operation in the Harsh Jovian Environment

    Science.gov (United States)

    Aslam, Shahid; Aslam, S.; Akturk, A.; Quilligan, G.

    2011-01-01

    ultimately impact the surface of Europa after the mission is completed. The current JEO mission concept includes a range of instruments on the payload, to monitor dynamic phenomena (such as Io's volcanoes and Jupiters atmosphere), map the Jovian magnetosphere and its interactions with the Galilean satellites, and characterize water oceans beneath the ice shells of Europa and Ganymede. The payload includes a low mass (3.7 Kg) and low power (ASIC that resides very close to the thermopile linear array outputs. Both the thermopile array and the MCD ASIC will need to show full functionality within the harsh Jovian radiation environment, operating at cryogenic temperatures, typically 150 K to 170 K. In the following, a radiation mitigation strategy together with a low risk Radiation-Hardened-By-Design (RHBD) methodology using commercial foundry processes is given for the design and manufacture of a MCD ASIC that will meet this challenge.

  5. Composite Materials under Extreme Radiation and Temperature Environments of the Next Generation Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Simos, N.

    2011-05-01

    In the nuclear energy renaissance, driven by fission reactor concepts utilizing very high temperatures and fast neutron spectra, materials with enhanced performance that exceeds are expected to play a central role. With the operating temperatures of the Generation III reactors bringing the classical reactor materials close to their performance limits there is an urgent need to develop and qualify new alloys and composites. Efforts have been focused on the intricate relations and the high demands placed on materials at the anticipated extreme states within the next generation fusion and fission reactors which combine high radiation fluxes, elevated temperatures and aggressive environments. While nuclear reactors have been in operation for several decades, the structural materials associated with the next generation options need to endure much higher temperatures (1200 C), higher neutron doses (tens of displacements per atom, dpa), and extremely corrosive environments, which are beyond the experience on materials accumulated to-date. The most important consideration is the performance and reliability of structural materials for both in-core and out-of-core functions. While there exists a great body of nuclear materials research and operating experience/performance from fission reactors where epithermal and thermal neutrons interact with materials and alter their physio-mechanical properties, a process that is well understood by now, there are no operating or even experimental facilities that will facilitate the extreme conditions of flux and temperature anticipated and thus provide insights into the behaviour of these well understood materials. Materials, however, still need to be developed and their interaction and damage potential or lifetime to be quantified for the next generation nuclear energy. Based on material development advances, composites, and in particular ceramic composites, seem to inherently possess properties suitable for key functions within the

  6. Composite Materials under Extreme Radiation and Temperature Environments of the Next Generation Nuclear Reactors

    International Nuclear Information System (INIS)

    Simos, N.

    2011-01-01

    In the nuclear energy renaissance, driven by fission reactor concepts utilizing very high temperatures and fast neutron spectra, materials with enhanced performance that exceeds are expected to play a central role. With the operating temperatures of the Generation III reactors bringing the classical reactor materials close to their performance limits there is an urgent need to develop and qualify new alloys and composites. Efforts have been focused on the intricate relations and the high demands placed on materials at the anticipated extreme states within the next generation fusion and fission reactors which combine high radiation fluxes, elevated temperatures and aggressive environments. While nuclear reactors have been in operation for several decades, the structural materials associated with the next generation options need to endure much higher temperatures (1200 C), higher neutron doses (tens of displacements per atom, dpa), and extremely corrosive environments, which are beyond the experience on materials accumulated to-date. The most important consideration is the performance and reliability of structural materials for both in-core and out-of-core functions. While there exists a great body of nuclear materials research and operating experience/performance from fission reactors where epithermal and thermal neutrons interact with materials and alter their physio-mechanical properties, a process that is well understood by now, there are no operating or even experimental facilities that will facilitate the extreme conditions of flux and temperature anticipated and thus provide insights into the behaviour of these well understood materials. Materials, however, still need to be developed and their interaction and damage potential or lifetime to be quantified for the next generation nuclear energy. Based on material development advances, composites, and in particular ceramic composites, seem to inherently possess properties suitable for key functions within the

  7. Deterministic and stochastic methods of calculation of polarization characteristics of radiation in natural environment

    Science.gov (United States)

    Strelkov, S. A.; Sushkevich, T. A.; Maksakova, S. V.

    2017-11-01

    We are talking about russian achievements of the world level in the theory of radiation transfer, taking into account its polarization in natural media and the current scientific potential developing in Russia, which adequately provides the methodological basis for theoretically-calculated research of radiation processes and radiation fields in natural media using supercomputers and mass parallelism. A new version of the matrix transfer operator is proposed for solving problems of polarized radiation transfer in heterogeneous media by the method of influence functions, when deterministic and stochastic methods can be combined.

  8. Earth Radiation Budget Experiment (ERBE) Data Sets for Global Environment and Climate Change Studies

    Science.gov (United States)

    Bess, T. Dale; Carlson, Ann B.; Denn, Fredrick M.

    1997-01-01

    For a number of years there has been considerable interest in the earth's radiation budget (ERB) or energy balance, and entails making the best measurements possible of absorbed solar radiation, reflected shortwave radiation (RSW), thermal outgoing longwave radiation (OLR), and net radiation. ERB data are fundamental to the development of realistic climate models and studying natural and anthropogenic perturbations of the climate. Much of the interest and investigations in the earth's energy balance predated the age of earth-orbiting satellites (Hunt et al., 1986). Beginning in the mid 1960's earth-orbiting satellites began to play an important role in making measurements of the earth's radiation flux although much effort had gone into measuring ERB parameters prior to 1960 (House et al., 1986). Beginning in 1974 and extending until the present time, three different satellite experiments (not all operating at the same time) have been making radiation budget measurements almost continually in time. Two of the experiments were totally dedicated to making radiation budget measurements of the earth, and the other experiment flown on NOAA sun-synchronous AVHRR weather satellites produced radiation budget parameters as a by-product. The heat budget data from the AVHRR satellites began collecting data in June 1974 and have operated almost continuously for 23 years producing valuable data for long term climate monitoring.

  9. Radiation-Hardened Memristor-based Memory for Extreme Environments, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA space exploration missions require radiation-hardened memory technologies that can survive and operate over a wide temperature range. Memristors...

  10. Radiation-Hardened Memristor-based Memory for Extreme Environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA space exploration missions require radiation-hardened memory technologies that can survive and operate over a wide temperature range. Memristors...

  11. Protection of people and environment from radiation risk through good regulatory practice

    Science.gov (United States)

    Jais, Azlina Mohammad; Hassan, Najwa

    2017-01-01

    The term "good regulatory practice" has seen growing frequency of usage worldwide, especially since the 2011 Fukushima nuclear incident. However, the term appears quite ambiguous as it may mean differently to different people. This leads us to the first important question: what does "good regulatory practice" actually mean? When used in conjunction with the Fukushima incident, do we imply that there is an absence of "good regulatory practice" in the Japanese' Nuclear and Industry Safety Agency (NISA)? This is quite troubling. It is clear that the term should be defined formally so that our understanding of "good regulatory practice" can be standardized. There is still another important question beyond agreeing on what "good regulatory practice" is: is "good regulatory practice" specific to a region, or is it global? And is it applicable only to nuclear regulators, or to all types of regulators per se? This paper aims to deliberate on the above mentioned questions. Specifically, we hope to discuss the "good regulatory practice" for atomic energy activities in order to protect the people and the environment from radiation risk of such activities. By understanding what "good regulatory practice" truly means, a newcomer country such as Malaysia can quickly learn and adopt these practices so as to assure a competent national nuclear regulatory authority who will be responsible in ensuring the safety, security and safeguards of peaceful atomic energy activities in the country including nuclear liability. In understanding this concept, a holistic approach will be taken by looking into example of advanced and newcomer countries of various nuclear regulatory authorities all around the world. Then the paper will focus on the challenges that the current nuclear regulatory authority in Malaysia which is Atomic Energy Licensing Board has, its challenges to follow the concept of "good regulatory practice" and its ways to overcome it. This study explore the initiatives could be

  12. Research into radiation protection. 1994 Programme report. Report on radiation departmental research programme on radiation protection, sponsored by the Federal Ministry for the Environment, Nature Conservation and Reactor Safety, and placed under the administrative and subject competence of the Federal Radiation Protection Office

    International Nuclear Information System (INIS)

    Goedde, R.; Schmitt-Hannig, A.; Thieme, M.

    1994-10-01

    On behalf of the Ministery for Environment, Nature Conservation and Nuclear Safety (BMU), the Federal Office for Radiation Protection is placing research and study contracts in the field of radiation protection. The results of these projects are used for developing radiation protection rules and to fulfill the special radiation protection tasks of the BMU, required by law. Planning, expert and administrative management, placing, assistance as well as expert evaluation of the results from these research projects lies within the responsibility of the Federal Office for Radiation Protection. This report provides information on preliminary and final results of radiation protection projects within the BMU Department Research Programme of the year 1994. (orig.) [de

  13. Research into radiation protection. 1995 Programme report. Report on radiation departmental research programme on radiation protection, sponsored by the Federal Ministry for the Environment, Nature Conservation and Reactor Safety, and placed under the administrative and subject competence of the Federal Radiation Protection Office

    International Nuclear Information System (INIS)

    Thieme, M.; Goedde, R.; Schmitt-Hannig, A.

    1996-01-01

    On behalf of the Ministry for Environment, Nature Conservation and Nuclear Safety (BMU), the Federal Office for Radiation Protection is placing research and study contracts in the field of radiation protection. The results of these projects are used for developing radiation protection rules and to fulfill the special radiation protection tasks of the BMU, required by law. Planning, expert and administrative management, placing, assistance as well as expert evaluation of the results from these research projects lies within the responsibility of the Federal Office for Radiation Protection. This report provides information on preliminary and final results of radiation protection projects within the BMU Department Research Programme of the year 1995. (orig.) [de

  14. Simulation of Earth-Moon-Mars Environments for the Assessment of Organ Doses

    Science.gov (United States)

    Kim, Myung-Hee; Schwadron, Nathan; Townsend, Lawrence W.; Cucinotta, Francis A.

    2010-01-01

    Space radiation environments for historically large solar particle events (SPE) and galactic cosmic rays (GCR) at solar minimum and solar maximum are simulated in order to characterize exposures to radio-sensitive organs for missions to low-Earth orbit (LEO), moon, and Mars. Primary and secondary particles for SPE and GCR are transported through the respective atmosphere of Earth or Mars, space vehicle, and astronaut s body tissues using the HZETRN/QMSFRG computer code. In LEO, exposures are reduced compared to deep space because particles are deflected by the Earth s magnetic field and absorbed by the solid body of the Earth. Geomagnetic transmission function as a function of altitude was applied for the particle flux of charged particles, and the shift or the organ exposures to higher velocity or lower stopping powers compared to those in deep space were analyzed. In the transport through Mars atmosphere, a vertical distribution of atmospheric thickness was calculated from the temperature and pressure data of Mars Global Surveyor, and the directional cosine distribution was implemented to describe the spherically distributed atmospheric distance along the slant path at each altitude. The resultant directional shielding by Mars atmosphere at solar minimum and solar maximum was used for the particle flux simulation at various altitudes on the Martian surface. Finally, atmospheric shielding was coupled with vehicle and body shielding for organ dose estimates. We made predictions of radiation dose equivalents and evaluated acute symptoms at LEO, moon, and Mars at solar minimum and solar maximum.

  15. An update on standards for radiation in the environment and associated estimates of risk

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1989-01-01

    This presentation reviews current and proposed standards, recommendations, and guidances for limiting routine radiation exposures of the public, and estimates the risk corresponding to standards, recommendations, and guidances. These estimates provide a common basis for comparing different criteria for limiting public exposures to radiation, as well as hazardous chemicals

  16. TOMS as a monitor of the ultraviolet radiation environment: applications to photobiology

    International Nuclear Information System (INIS)

    Frederick, J.E.

    1987-01-01

    The flux of biologically relevant ultraviolet radiation that reaches the surface of the Earth varies with the ozone amount, surface reflectivity, and cloudcover. The Total Ozone Mapping Spectrometer (TOMS) provides information relevant to all three items. A recent application of satellite-based ozone measurements has been to develop climatologies of the biologically significant UV-B radiation reaching the Earth's surface. A growing body of research suggests that UV-B radiation tends to suppress the immune system of laboratory mice. At tropical latitudes, it is likely that parasitical diseases develop most readily in people who have experienced immune system suppression from UV-B exposure. The computed distribution of surface radiation combined with information on disease incidence may clarify the role of UV-B as a suppressor of the human immune system. TOMS used in conjunction with radiative transfer calculations can provide information of relevance in photobiology

  17. How Extreme is TRAPPIST-1? A look into the planetary system’s extreme-UV radiation environment

    Science.gov (United States)

    Peacock, Sarah; Barman, Travis; Shkolnik, Evgenya L.

    2018-01-01

    The ultracool dwarf star TRAPPIST-1 hosts three earth-sized planets at orbital distances where water has the potential to exist in liquid form on the planets’ surface. Close-in exoplanets, such as these, become vulnerable to water loss as stellar XUV radiation heats and expands their upper atmospheres. Currently, little is known about the high-energy radiation environment around TRAPPIST-1. Recent efforts to quantify the XUV radiation rely on empirical relationships based on X-ray or Lyman alpha line observations and yield very different results. The scaling relations used between the X-ray and EUV emission result in high-energy irradiation of the planets 10-1000x greater than present day Earth, stripping atmospheres and oceans in 1 Gyr, while EUV estimated from Lyman alpha flux is much lower. Here we present upper-atmosphere PHOENIX models representing the minimum and maximum potential EUV stellar flux from TRAPPIST-1. We use GALEX FUV and NUV photometry for similar aged M stars to determine the UV flux extrema in an effort to better constrain the high-energy radiation environment around TRAPPIST-1.

  18. Using the FLUKA Monte Carlo Code to Simulate the Interactions of Ionizing Radiation with Matter to Assist and Aid Our Understanding of Ground Based Accelerator Testing, Space Hardware Design, and Secondary Space Radiation Environments

    Science.gov (United States)

    Reddell, Brandon

    2015-01-01

    Designing hardware to operate in the space radiation environment is a very difficult and costly activity. Ground based particle accelerators can be used to test for exposure to the radiation environment, one species at a time, however, the actual space environment cannot be duplicated because of the range of energies and isotropic nature of space radiation. The FLUKA Monte Carlo code is an integrated physics package based at CERN that has been under development for the last 40+ years and includes the most up-to-date fundamental physics theory and particle physics data. This work presents an overview of FLUKA and how it has been used in conjunction with ground based radiation testing for NASA and improve our understanding of secondary particle environments resulting from the interaction of space radiation with matter.

  19. Scenario of a dirty bomb in an urban environment and acute management of radiation poisoning and injuries.

    Science.gov (United States)

    Chin, F K C

    2007-10-01

    In the new security environment, there is a clear and present danger of terrorists using non-conventional weapons to inflict maximum psychological and economic damage on their targets. This article examines two scenarios of radiation contamination and injury, one accidental in nature leading to environmental contamination, and another of deliberate intent resulting in injury and death. This article also discusses the management of injury from radiological dispersion devices or dirty bombs, with emphasis on the immediate aftermath as well as strategy recommendations.

  20. A possible approach for the assessment of radiation effects on populations of wild organisms in radionuclide-contaminated environments?

    International Nuclear Information System (INIS)

    Woodhead, D.S.

    2003-01-01

    It is frequently asserted that measures to protect the biotic environment from increased radiation exposures arising from human activities should be focussed on the population rather than the individual. It is, however, difficult (if not impossible) to identify any population-specific attributes that can be affected by radiation exposure directly rather than through the mediation of direct, known and identifiable effects in individual organisms. Indeed, it is often conceded that this difficulty forces attention to be refocussed onto the effects in individuals. Regulatory controls on radioactive waste management and disposal could then be implemented to ensure that any radiation effects in individual native plants and animals remain at, or below, some acceptable level (yet to be defined). Nevertheless, the question remains as to whether such controls would also provide for the protection of the population. An answer to this question depends on the availability of a model that allows the integration of the known effects of radiation exposure on the mortality, morbidity, fertility and fecundity of individuals into an assessment of the possible impact at the population level. The utility of one such approach, the Leslie Matrix Model, is explore in respect of a fish population (the plaice, Pleuronectes platessa). This initial implementation of the population model is simplistic (and, certainly, environmentally unrealistic), but it is concluded that the output from the model does provide some insights into how the population might respond to radiation-induced changes in individual attributes, and that further development in the direction of increased realism is fully warranted

  1. Design Issues for Using Magnetic Materials in Radiation Environments at Elevated Temperature

    Science.gov (United States)

    Bowman, Cheryl L.

    2013-01-01

    One of the challenges of designing motors and alternators for use in nuclear powered space missions is accounting for the effects of radiation. Terrestrial reactor power plants use distance and shielding to minimize radiation damage but space missions must economize volume and mass. Past studies have shown that sufficiently high radiation levels can affect the magnetic response of hard and soft magnetic materials. Theoretical models explaining the radiation-induced degradation have been proposed but not verified. This paper reviews the literature and explains the cumulative effects of temperature, magnetic-load, and radiation-level on the magnetic properties of component materials. Magnetic property degradation is very specific to alloy choice and processing history, since magnetic properties are very much entwined with specific chemistry and microstructural features. However, there is basic theoretical as well as supportive experimental evidence that the negative impact to magnetic properties will be minimal if the bulk temperature of the material is less than fifty percent of the Curie temperature, the radiation flux is low, and the demagnetization field is small. Keywords: Magnets, Permanent Magnets, Power Converters, Nuclear Electric Power Generation, Radiation Tolerance.

  2. Cancer and environment. Tobacco, pesticides, radiations, diet: a document for the World Meeting on Ecology

    International Nuclear Information System (INIS)

    Lopes, E.R.; Mendonca, G.A.S.; Goldfarb, L.M.C.S.

    1992-01-01

    A detailed evaluation concerning the cancer etiology is presented. Several aspects on chemical agents role are described, as the relationship between tobacco and disease development, active and passive smoking, environmental pollution, occupational diseases, soil use and pesticides. The radiation exposure is studied, including solar radiation and risk factors for cutaneous malignant melanoma, ionizing radiations, radiological accidents, procedures of radioactive control in Brazil. Mutagens, carcinogens and tumor promoters in daily food are discussed as well as factors for reducing the risk of cancer development. (M.A.C.)

  3. Leo Kunnas, sõdurjumala teener / Leo Kunnas ; interv. Eve Jaakson

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kaitsejõudude peastaabi operatiivosakonna ülem kolonelleitnant Leo Kunnas räägib Iraagi sõja kogemustest ja oma raamatust "Viiv pikas sõjas. Märkmeid Iraagi sõjast", riigikaitsest, kaitseväeteenistusest, kaitseminister Jürgen Ligist, kaitsepoliitikast, NATO-st, sõjalisest koostööst, perekonnast. Kommenteerivad Sten Reimann ja Venno Loosaar

  4. Irradiation tests of critical components for remote handling in gamma radiation environment

    International Nuclear Information System (INIS)

    Obara, Henjiro; Kakudate, Satoshi; Oka, Kiyoshi

    1994-08-01

    Since the fusion power core of a D-T fusion reactor will be highly activated once it starts operation, personnel access will be prohibited so that assembly and maintenance of the components in the reactor core will have to be totally conducted by remote handling technology. Fusion experimental reactors such as ITER require unprecedented remote handling equipments which are tolerable under gamma radiation of more than 10 6 R/h. For this purpose, the Japan Atomic Energy Research Institute (JAERI) has been developing radiation hard components for remote handling purpose and a number of key components have been tested over 10 9 rad at a radiation dose rate of around 10 6 R/h, using Gamma Ray Radiation Test Facility in JAERI-Takasaki Establishment. This report summarizes the irradiation test results and the latest status of AC servo motor, potentiometer, optical elements, lubricant, sensors and cables, which are key elements of the remote handling system. (author)

  5. Management of ionizing radiation sources in university, medical and industrial environments

    International Nuclear Information System (INIS)

    2000-01-01

    This conference treats several subjects relative to the use of radioactive sources. The first session comprises three articles about ionizing sources and regulation. The second session, with three articles, tackles the question of radiation protection in the use of sources in industrial field. The third session, four articles, treats the same question but in the medicine and university media. The fourth session (three articles) is devoted to the organisation of radiation protection in the case of accidents. The fifth session concerns the management of spent sources (three articles). The sixth session studies the radiation protection of sources in Europe. The seventh and final session ends with the part and coordination of actors in radiation protection in the sources management (three articles). (N.C.)

  6. The development of an international framework for the radiation protection of the environment

    International Nuclear Information System (INIS)

    Gonzalez, A.; Jova Sed, L.

    2004-01-01

    This paper comprises an overview of the Agency responsibilities, related to environmental radiation protection; its historical involvement in this issue; the context of its current work programme; and a number of issues for further consideration. (authors)

  7. High intensity radiated field external environments for civil aircraft operating in the United States of America

    Science.gov (United States)

    1998-12-01

    NAWCAD Patuxent River, Maryland, was tasked by the FAA to determine the High Intensity Radiated Field (HIRF) levels for civil aircraft operating in the U.S. The electromagnetic field survey will apply to civil aircraft seeking FAA certification under...

  8. A Review of NASA's Radiation-Hardened Electronics for Space Environments Project

    Science.gov (United States)

    Keys, Andrew S.; Adams, James H.; Patrick, Marshall C.; Johnson, Michael A.; Cressler, John D.

    2008-01-01

    NASA's Radiation Hardened Electronics for Space Exploration (RHESE) project develops the advanced technologies required to produce radiation hardened electronics, processors, and devices in support of the requirements of NASA's Constellation program. Over the past year, multiple advancements have been made within each of the RHESE technology development tasks that will facilitate the success of the Constellation program elements. This paper provides a brief review of these advancements, discusses their application to Constellation projects, and addresses the plans for the coming year.

  9. TLD survey of natural radiation environment along the south-west coast of India

    International Nuclear Information System (INIS)

    Sunta, C.M.; David, M.; Subbaratnam, T.

    1980-01-01

    An extensive population and house dosimetry programme using thermoluminescence dosimetry was carried out in the areas of high level natural background radiation (due to monazite deposits) in Kerala during 1968-70. Further surveys were carried out in the areas not covered under the above-mentioned programme and the results are presented. The radiation exposure from external sources only is measured. (M.G.B.)

  10. Influence of Coupled Radiation and Ablation on the Aerothermodynamic Environment of Planetary Entry Vehicles

    Science.gov (United States)

    Johnston, Christopher O.; Gnoffo, Peter A.; Mazaheri, Alireza

    2013-01-01

    A review of recently published coupled radiation and ablation capabilities involving the simulation of hypersonic flowfields relevant to Earth, Mars, or Venus entry is presented. The three fundamental mechanisms of radiation coupling are identified as radiative cooling, precursor photochemistry, and ablation-radiation interaction. The impact of these mechanisms are shown to be significant for a 3 m radius sphere entering Earth at hypothetical Mars return conditions (approximately 15 km/s). To estimate the influence precursor absorption on the radiative flux for a wide range of conditions, a simplified approach is developed that requires only the non-precursor solution. Details of a developed coupled ablation approach, which is capable of treating both massively ablating flowfields in the sublimation regime and weakly ablating diffusion Climited oxidation cases, are presented. A review of the two primary uncoupled ablation approximations, identified as the blowing correction and film coefficient approximations, is made and their impact for Earth and Mars entries is shown to be significant for recession and convective heating predictions. Fully coupled ablation and radiation simulations are presented for the Mars return sphere throughout its entire trajectory. Applying to the Mars return sphere the Pioneer- Venus heritage carbon phenolic heatshield, which has properties available in the open literature, the differences between steady state ablation and coupling to a material response code are shown to be significant.

  11. Evaluating a radiation monitor for mixed-field environments based on SRAM technology

    CERN Document Server

    Tsiligiannis, G; Bosio, A; Girard, P; Pravossoudovitch, S; Todri, A; Virazel, A; Mekki, J; Brugger, M; Wrobel, F; Saigne, F

    2014-01-01

    Instruments operating in particle accelerators and colliders are exposed to radiations that are composed of particles of different types and energies. Several of these instruments often embed devices that are not hardened against radiation effects. Thus, there is a strong need for mon- itoring the levels of radiation inside the mixed-field radiation areas, throughout different positions. Different metrics exist for measuring the radiation damage induced to electronic devices, such as the Total Ionizing Dose (TID), the Displacement Damage (DD) and of course the fluence of parti- cles for estimating the error rates of the electronic devices among other applications. In this paper, we propose an SRAM based monitor, that is used to define the fluence of High Energy Hadrons (HEH) by detecting Single Event Upsets in the memory array. We evaluated the device by testing it inside the H4IRRAD area of CERN, a test area that reproduces the radiation conditions inside the Large Hadron Collider (LHC) tunnel and its shield...

  12. Petróleo, Royalties e Pobreza

    Directory of Open Access Journals (Sweden)

    Gicélia Mendes da Silva

    2009-08-01

    Full Text Available A exploração do petróleo se constitui num elemento significativo para a economia sergipana. A contradição existente entre o subsolo rico e a população pobre levanta indagações a respeito da gestão destes recursos e as condições de vida da população. Tais condições, aliadas à entrada de novos atores na exploração do petróleo em Sergipe e à gestão dos recursos advindos da exploração, vêm incutindo relações peculiares à política neoliberal na região e em Sergipe. O estudo foi desenvolvido a partir da análise e cruzamento de informações disponíveis na Agência Nacional do Petróleo (ANP, Instituto Brasileiro de Geografia e Estatística (IBGE, Tribunal de Contas da União (TCU e PETROBRAS, dentre outros setores. A carência de políticas sociais que ofereçam às populações condições de inserção nas questões política, econômica e social da região produtora de petróleo tem impedido o desenvolvimento efetivo e mudança no padrão de vida das populações, evidenciando a incoerência entre os altos valores depositados nos cofres públicos municipais decorrentes dos royalties e os elevados índices de pobreza apresentados na região. Tal constatação reforça a ideia de que as políticas públicas devem primar pela redução da desigualdade a partir da gestão responsável dos recursos públicos. Abstract OIL, ROYALTIES AND POVERTY The exploitation of oil has significant element for the Sergipe´s economy. However, the contradiction between the subsoils rich and poor people raises key questions about the management of these resources and the living conditions of the population. Such conditions, the entry of new actors in the scenery for the exploration of oil in Sergipe and the management of resources of exploration, instilling relations peculiar to neo-liberal policy in the region and in Sergipe. The study was developed from the analysis and crossing of information available in the national agency oil (ANP

  13. Experimental investigation of the radiation shielding efficiency of a MCP detector in the radiation environment near Jupiter’s moon Europa

    Energy Technology Data Exchange (ETDEWEB)

    Tulej, M., E-mail: marek.tulej@space.unibe.ch [Space Research and Planetary Sciences, Physics Institute, University of Bern, CH-3012 Bern (Switzerland); Meyer, S.; Lüthi, M.; Lasi, D.; Galli, A.; Piazza, D. [Space Research and Planetary Sciences, Physics Institute, University of Bern, CH-3012 Bern (Switzerland); Desorgher, L.; Reggiani, D.; Hajdas, W. [Laboratory of Particle Physics, Paul Scherrer Institute, CH-5232, Villigen (Switzerland); Karlsson, S.; Kalla, L. [Swedish Institute of Space Physics, Space Kampus 1, Kiruna (Sweden); Wurz, P. [Space Research and Planetary Sciences, Physics Institute, University of Bern, CH-3012 Bern (Switzerland)

    2016-09-15

    Neutral Ion Mass spectrometer (NIM) is one of the instruments in the Particle Environmental Package (PEP) designed for the JUICE mission of ESA to the Jupiter system. NIM, equipped with a sensitive MCP ion detector, will conduct detailed measurements of the chemical composition of Jovian icy moons exospheres. To achieve high sensitivity of the instrument, radiation effects due to the high radiation background (high-energy electrons and protons) around Jupiter have to be minimised. We investigate the performance of an Al–Ta–Al composite stack as a potential shielding against high-energy electrons. Experiments were performed at the PiM1 beam line of the High Intensity Proton Accelerator Facilities located at the Paul Scherrer Institute, Villigen, Switzerland. The facility delivers a particle beam containing e{sup −}, μ{sup −} and π{sup −} with momentum from 17.5 to 345 MeV/c (Hajdas et al., 2014). The measurements of the radiation environment generated during the interaction of primary particles with the Al–Ta–Al material were conducted with dedicated beam diagnostic methods and with the NIM MCP detector. In parallel, modelling studies using GEANT4 and GRAS suites were performed to identify products of the interaction and predict ultimate fluxes and particle rates at the MCP detector. Combination of experiment and modelling studies yields detailed characterisation of the radiation fields produced by the interaction of the incident e{sup −} with the shielding material in the range of the beam momentum from 17.5 to 345 MeV/c. We derived the effective MCP detection efficiency to primary and secondary radiation and effective shielding transmission coefficients to incident high-energy electron beam in the range of applied beam momenta. This study shows that the applied shielding attenuates efficiently high-energy electrons. Nevertheless, owing to nearly linear increase of the bremsstrahlung production rate with incident beam energy, above 130 MeV their

  14. Web-based description of the space radiation environment using the Bethe-Bloch model

    Science.gov (United States)

    Cazzola, Emanuele; Calders, Stijn; Lapenta, Giovanni

    2016-01-01

    Space weather is a rapidly growing area of research not only in scientific and engineering applications but also in physics education and in the interest of the public. We focus especially on space radiation and its impact on space exploration. The topic is highly interdisciplinary, bringing together fundamental concepts of nuclear physics with aspects of radiation protection and space science. We give a new approach to presenting the topic by developing a web-based application that combines some of the fundamental concepts from these two fields into a single tool that can be used in the context of advanced secondary or undergraduate university education. We present DREADCode, an outreach or teaching tool to rapidly assess the current conditions of the radiation field in space. DREADCode uses the available data feeds from a number of ongoing space missions (ACE, GOES-13, GOES-15) to produce a first order approximation of the radiation dose an astronaut would receive during a mission of exploration in deep space (i.e. far from the Earth’s shielding magnetic field and from the radiation belts). DREADCode is based on an easy-to-use GUI interface available online from the European Space Weather Portal (www.spaceweather.eu/dreadcode). The core of the radiation transport computation to produce the radiation dose from the observed fluence of radiation observed by the spacecraft fleet considered is based on a relatively simple approximation: the Bethe-Bloch equation. DREADCode also assumes a simplified geometry and material configuration for the shields used to compute the dose. The approach is approximate and sacrifices some important physics on the altar of rapid execution time, which allows a real-time operation scenario. There is no intention here to produce an operational tool for use in space science and engineering. Rather, we present an educational tool at undergraduate level that uses modern web-based and programming methods to learn some of the most important

  15. Web-based description of the space radiation environment using the Bethe–Bloch model

    International Nuclear Information System (INIS)

    Cazzola, Emanuele; Lapenta, Giovanni; Calders, Stijn

    2016-01-01

    Space weather is a rapidly growing area of research not only in scientific and engineering applications but also in physics education and in the interest of the public. We focus especially on space radiation and its impact on space exploration. The topic is highly interdisciplinary, bringing together fundamental concepts of nuclear physics with aspects of radiation protection and space science. We give a new approach to presenting the topic by developing a web-based application that combines some of the fundamental concepts from these two fields into a single tool that can be used in the context of advanced secondary or undergraduate university education. We present DREADCode, an outreach or teaching tool to rapidly assess the current conditions of the radiation field in space. DREADCode uses the available data feeds from a number of ongoing space missions (ACE, GOES-13, GOES-15) to produce a first order approximation of the radiation dose an astronaut would receive during a mission of exploration in deep space (i.e. far from the Earth’s shielding magnetic field and from the radiation belts). DREADCode is based on an easy-to-use GUI interface available online from the European Space Weather Portal (www.spaceweather.eu/dreadcode). The core of the radiation transport computation to produce the radiation dose from the observed fluence of radiation observed by the spacecraft fleet considered is based on a relatively simple approximation: the Bethe–Bloch equation. DREADCode also assumes a simplified geometry and material configuration for the shields used to compute the dose. The approach is approximate and sacrifices some important physics on the altar of rapid execution time, which allows a real-time operation scenario. There is no intention here to produce an operational tool for use in space science and engineering. Rather, we present an educational tool at undergraduate level that uses modern web-based and programming methods to learn some of the most

  16. Radiation

    International Nuclear Information System (INIS)

    Davidson, J.H.

    1986-01-01

    The basic facts about radiation are explained, along with some simple and natural ways of combating its ill-effects, based on ancient healing wisdom as well as the latest biochemical and technological research. Details are also given of the diet that saved thousands of lives in Nagasaki after the Atomic bomb attack. Special comment is made on the use of radiation for food processing. (U.K.)

  17. Environment

    Science.gov (United States)

    2005-01-01

    biodiversity. Consequently, the major environmental challenges facing us in the 21st century include: global climate change , energy, population and food...technological prowess, and security interests. Challenges Global Climate Change – Evidence shows that our environment and the global climate ... urbanization will continue to pressure the regional environment . Although most countries have environmental protection ministries or agencies, a lack of

  18. Concepts for the calculation of radiation exposure in the environment of nuclear plants for planning and surveillance purposes

    International Nuclear Information System (INIS)

    Brenk, H.D.; Vogt, K.J.; Bruessermann, K.; Schwarz, G.

    1977-01-01

    In connection with the release of radioactive substances from nuclear plants, the following requirements are to be met in respect of the assessment of radiation exposure of persons in the environment of the plant: for the purpose of planning and licencing nuclear plants, the release rates of radioactive substances are to be limited to such a degree that the dose limit values specified in the Radiation Protection Ordinance are not exceeded at any time or on any site. This applies possibly under consideration of the pre-exposure rate. For long-lived radionuclides this requirement involves the calculation of annual doses at the end of a period determined by the time of operation of the plant and by the exposure time of the persons. During the operation of nuclear plants it is necessary to calculate the radiation exposure rates resulting from the emission measured for the year of reference. This application requires the calculation of the dose commitment resulting in the future on the basis of annual emissions for persons living in the environment of the plant. In connection with the long-term prediction of the environmental impact caused by the entire nuclear industry, problems will also be arising in conjunction with the case history of the environmental exposure being subject to respective alterations as a result of additional plants

  19. First Calibrations of Alanine and Radio-Photo-Luminescence Dosemeters to a Hadronic Radiation Environment

    CERN Document Server

    Fürstner, Markus; Floret, Idelette; Forkel-Wirth, Doris; Mayer, Sabine; Menzel, Hans Gregor; Vincke, Helmut H

    2005-01-01

    Alanine and Radio-Photo-Luminescence (RPL) dosimeters are used to monitor radiation doses occurring inside the tunnels of all CERN accelerators including the Large Hadron Collider (LHC). They are placed close to radiation sensitive machine components like cables or insulation of magnet coils to predict their remaining lifetime. The dosimeters are exposed to mixed high-energy radiation fields. However, up to now both dosimeter types are calibrated to 60Co-photons only. In order to study the response of RPL and alanine dosimeters to mixed particle fields like those occurring at CERN's accelerators, an irradiation campaign at the CERN-EC High-Energy Reference field Facility (CERF-field) was performed. Moreover, the dosimeters were first time calibrated to a proton radiation field of a constant momentum of 24 GeV/c. In addition to the experiment FLUKA Monte Carlo simulations were carried out, which provide information concerning the energy deposition and the radiation field at the dosimeter locations.

  20. Concepts and challenges in cancer risk prediction for the space radiation environment

    Science.gov (United States)

    Barcellos-Hoff, Mary Helen; Blakely, Eleanor A.; Burma, Sandeep; Fornace, Albert J.; Gerson, Stanton; Hlatky, Lynn; Kirsch, David G.; Luderer, Ulrike; Shay, Jerry; Wang, Ya; Weil, Michael M.

    2015-07-01

    Cancer is an important long-term risk for astronauts exposed to protons and high-energy charged particles during travel and residence on asteroids, the moon, and other planets. NASA's Biomedical Critical Path Roadmap defines the carcinogenic risks of radiation exposure as one of four type I risks. A type I risk represents a demonstrated, serious problem with no countermeasure concepts, and may be a potential "show-stopper" for long duration spaceflight. Estimating the carcinogenic risks for humans who will be exposed to heavy ions during deep space exploration has very large uncertainties at present. There are no human data that address risk from extended exposure to complex radiation fields. The overarching goal in this area to improve risk modeling is to provide biological insight and mechanistic analysis of radiation quality effects on carcinogenesis. Understanding mechanisms will provide routes to modeling and predicting risk and designing countermeasures. This white paper reviews broad issues related to experimental models and concepts in space radiation carcinogenesis as well as the current state of the field to place into context recent findings and concepts derived from the NASA Space Radiation Program.

  1. "BION-M" No.1 spacecraft radiation environment as observed in April-May 2013. Comparison with ISS data

    Science.gov (United States)

    Dachev, Tsvetan; Horneck, Gerda; Reitz, Guenther; Semkova, Jordanka; Schuster, Martin; Lebert, Michael; Malchev, Stefan; Tomov, Borislav; Matviichuk, Yury; Dimitrov, Plamen; Ivanova, Olga; Haeder, Donat-Peter; Bankov, Nikolai; Shurshakov, Vyacheslav; Benghin, Victor; K, Rositza

    Space radiation has been monitored in the period 19 April-13 May 2013 using RD3-B3 spectrometer-dosimeter on board the Russian recoverable satellite "BION-M" No.1. The instrument was mounted inside of the satellite pressurized volume together with biological objects and samples. RD3-B3 instrument is a battery operated version of the spare model of the R3D-B3 instrument developed and successfully worked on the ESA Biopan-6 facility on Foton M3 satellite in September 2007. Cosmic ionizing radiation has been monitored and separated in 256 deposited energy spectra, which were further used for determination of the absorbed dose rate and flux. The obtained history of accumulation and the daily and hourly values for the space radiation are presented in the paper ant they can contribute to a better understanding of the results from the biological experiments. Analogical data were obtained simultaneously on the International Space Station (ISS) using the Liulin-5 charged particle telescope. The paper summarizes the results for the global distribution of the Earth radiation environment at the altitude of the "BION-M" No.1 spacecraft and compares these data with the Liulin-5 data at the ISS and with AP/AE-8 MAX model.

  2. Radiation protection at the RA Reactor in 1985, Part -2, Annex 1, Radioactivity control of working environment, dosimetry

    International Nuclear Information System (INIS)

    Ninkovic, M.; Bjelanovic, J.; Minincic, Z.; Komatina, R.; Raicevic, J.

    1985-01-01

    This report contains data and analysis of the of measured sample results collected during radiation protection control in the working environment of the RA reactor. First part contains basic exposure values and statistical review of the the total number of radiation measurements. It includes contents of radioactive gasses and effluents in the air, as well as the level of surface contamination of clothes and uncovered parts of the personnel bodies. Second part deals with the analysis of personnel doses. It was found that the maximum individual dose from external irradiation amounted to 8.2 mSV during past 10 months. Individual exposures for 7/10 of the personnel were less than 1/10 of the annual permissible exposure. Data are compared to radiation doses for last year and previous five years. Third part of this annex contains basic data about the quantity of collected radioactive waste, total quantity of contaminated and decontaminated surfaces. The last part analyzes accidents occurred at the reactor during 1985. It was found that there have been no accidents that could cause significant contamination of working surfaces and components nor radiation exposure of the personnel [sr

  3. Irradiation tests of critical components for remote handling system in gamma radiation environment

    International Nuclear Information System (INIS)

    Obara, Kenjiro; Kakudate, Satoshi; Oka, Kiyoshi

    1996-03-01

    This report covers the gamma ray irradiation tests according to the Agreement of ITER R and D Task (T35) in 1994 and describes radiation hardness of the standard components for the ITER remote handling system which are categorized into the robotics (Subtask-1), the viewing system (Subtask-2) and the common components (Subtask-3). The gamma ray irradiation tests have been conducted using No.2 and No.3 cells at the cobalt building of Takasaki Establishment in JAERI. The radiation source is cobalt sixty (Co-60), and the maximum dose rate of No.2 and No.3 cells is about 1x10 6 R/h and 2x10 6 R/h, respectively. The environmental conditions of the irradiation tests are described below and all of components excepting electrical wires have been tested in the No.2 cell. [No.2 cell : Atmosphere and ambient temperature No.3 cell : Nitrogen gas and 250degC] As a whole, many of components have been irradiated up to the rated dose of around 1x10 10 rads and the following main results are obtained. The developed AC servo motor and periscope for radiation use have shown excellent durability with the radiation hardness tolerable for more than 10 9 rads. An electrical connector compatible with remote operation has also shown no degradation of electrical characteristics after the irradiation of 10 10 rads. As for polyimide insulated wires, the mechanical and electrical characteristics are not degradated after the irradiation of 10 9 rads and more radiation hardness can be expected than the anticipation. On the contrary, standard position sensors such as rotary encoder show extremely low radiation hardness and further efforts have to be made for improvements. (J.P.N.)

  4. A Multi-Environment Thermal Control System With Freeze-Tolerant Radiator, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Future space exploration missions require advanced thermal control systems (TCS) to dissipate heat from spacecraft, rovers, or habitats to external environments. We...

  5. Radioactivity levels in Indian coal and some technologically enhanced exposure to natural radiation environment of India

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Mishra, U.C.

    1988-01-01

    The summary of results of gamma-spectrometric measurements of natural radioactivity levels in coal from mines, coal, fly-ash, slag and soil samples from thermal power plants in India are presented. These constitute the sources of technologic ally enhanced exposures to natural radiation. Brief description of sampling and measurement procedure is given. Radiation dose to the population from coal fired power plants for electricity generation have been calculated using the model developed by UNSCEAR and ORNL reports with correction for local population density. (author). 13 refs., 7 tabs., 8 figs

  6. Final report on the project research 'assessment of radiation exposure of the public to radioactivities related to the environment and food chain'. April 1988 - March 1992

    International Nuclear Information System (INIS)

    1994-03-01

    This publication is the collection of the reports on the project research 'Assessment of Radiation Exposure of the Public to Radioactivities Related to the Environment and Food Chain'. The 16 of the reports are indexed individually. (J.P.N.)

  7. Particle Laden Turbulence in a Radiation Environment Using a Portable High Preformace Solver Based on the Legion Runtime System

    Science.gov (United States)

    Torres, Hilario; Iaccarino, Gianluca

    2017-11-01

    Soleil-X is a multi-physics solver being developed at Stanford University as a part of the Predictive Science Academic Alliance Program II. Our goal is to conduct high fidelity simulations of particle laden turbulent flows in a radiation environment for solar energy receiver applications as well as to demonstrate our readiness to effectively utilize next generation Exascale machines. The novel aspect of Soleil-X is that it is built upon the Legion runtime system to enable easy portability to different parallel distributed heterogeneous architectures while also being written entirely in high-level/high-productivity languages (Ebb and Regent). An overview of the Soleil-X software architecture will be given. Results from coupled fluid flow, Lagrangian point particle tracking, and thermal radiation simulations will be presented. Performance diagnostic tools and metrics corresponding the the same cases will also be discussed. US Department of Energy, National Nuclear Security Administration.

  8. Preliminary design of CERN Future Circular Collider tunnel: first evaluation of the radiation environment in critical areas for electronics

    Directory of Open Access Journals (Sweden)

    Infantino Angelo

    2017-01-01

    Full Text Available As part of its post-LHC high energy physics program, CERN is conducting a study for a new proton-proton collider, called Future Circular Collider (FCC-hh, running at center-of-mass energies of up to 100 TeV in a new 100 km tunnel. The study includes a 90-350 GeV lepton collider (FCC-ee as well as a lepton-hadron option (FCC-he. In this work, FLUKA Monte Carlo simulation was extensively used to perform a first evaluation of the radiation environment in critical areas for electronics in the FCC-hh tunnel. The model of the tunnel was created based on the original civil engineering studies already performed and further integrated in the existing FLUKA models of the beam line. The radiation levels in critical areas, such as the racks for electronics and cables, power converters, service areas, local tunnel extensions was evaluated.

  9. The practical use of an interactive visualization and planning tool for intervention planning in particle accelerator environments with ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Fabry, Thomas, E-mail: thomas.fabry@cern.ch [European Organization for Nuclear Research, CERN, CH-1211 Genève 23 (Switzerland); Blaha, Jan; Vanherpe, Liesbeth [European Organization for Nuclear Research, CERN, CH-1211 Genève 23 (Switzerland); Braesch, Christian; Tabourot, Laurent [SYMME, Université de Savoie, Polytech Annecy-Chambéry, 5 Chemin de Bellevue, 74944 Annecy le Vieux (France); Feral, Bruno [European Organization for Nuclear Research, CERN, CH-1211 Genève 23 (Switzerland)

    2014-04-11

    A core issue during the planning of a maintenance intervention in a facility with ionizing radiation is the minimization of the integrated equivalent dose contracted by the maintenance workers during the intervention. In this work, we explore the use of a technical-scientific software program facilitating the intervention planning in irradiated environments using sound mathematical concepts. We show how the software can be used in planning future operations using a case studies: the decommissioning of a beam dump for a linear 160 MeV H{sup −} accelerator. Interactive visualization of the facilities and radiation levels, as well as tools for interactive trajectory planning are explored, as well as automatic calculation of the expected integrated individual dose contracted during an intervention.

  10. Low noise monolithic Si JFETs for operation in the 90-300K Range and in high radiation environments

    International Nuclear Information System (INIS)

    Radeka, V.; Citterio, M.; Rescia, S.; Manfredi, P.F.; Speziali, V.

    1994-12-01

    Development of low noise preamplifters for large ionization chambers with liquid argon (LAr) and liquid krypton (LKr) used in high energy physics experiments for measurement of energy of charged particles and photons requires die choice of a technology able to withstand the environment: a temperature of 90 K -120 K; an ionizing radiation dose of 1-2 Mrad; a neutron fluence of 0.5 -1.10 14 n/cm 2 . Silicon JFETs by virtue of their reliable noise behavior and their intrinsic radiation hardness appear to be very suitable devices for applications both at room and cryogenic temperatures. We describe the noise properties of JFET devices and a monolithic preamplifier suitable for amplification of charge and current signals

  11. The practical use of an interactive visualization and planning tool for intervention planning in particle accelerator environments with ionizing radiation

    CERN Document Server

    Fabry, Thomas; Vanherpe, Liesbeth; Braesch, Christian; Tabourot, Laurent; Feral, Bruno

    2014-01-01

    A core issue during the planning of a maintenance intervention in a facility with ionizing radiation is the minimization of the integrated equivalent dose contracted by the maintenance workers during the intervention. In this work, we explore the use of a technical-scientific software program facilitating the intervention planning in irradiated environments using sound mathematical concepts. We show how the software can be used in planning future operations using a case studies: the decommissioning of a beam dump for a linear 160 MeV H− accelerator. Interactive visualization of the facilities and radiation levels, as well as tools for interactive trajectory planning are explored, as well as automatic calculation of the expected integrated individual dose contracted during an intervention.

  12. Observation of radiation environment in the International Space Station in 2012–March 2013 by Liulin-5 particle telescope

    Directory of Open Access Journals (Sweden)

    Semkova Jordanka

    2014-01-01

    Full Text Available Since June 2007 the Liulin-5 charged particle telescope, located in the spherical tissue-equivalent phantom of the MATROSHKA-R project onboard the International Space Station (ISS, has been making measurements of the local energetic particle radiation environment. From 27 December 2011 to 09 March 2013 measurements were conducted in and outside the phantom located in the MIM1 module of the ISS. In this paper Liulin-5 dose rates, due to galactic cosmic rays and South Atlantic Anomaly trapped protons, measured during that period are presented. Particularly, dose rates and particle fluxes for the radiation characteristics in the phantom during solar energetic particle (SEP events occurring in March and May 2012 are discussed. Liulin-5 SEP observations are compared with other ISS data, GOES proton fluxes as well as with solar energetic particle measurements obtained onboard the Mir space station during previous solar cycles.

  13. Terrestrial Gamma Radiation Exposure Measurement and Risk Estimates in the Environments of Major Industries In Ota, Nigeria

    Directory of Open Access Journals (Sweden)

    Abodunrin Oluwasayo Peter

    2016-11-01

    Full Text Available When fast estimates are required, the in-situ method is more appropriate as this allows for quick results; preventing further exposure of the public and permitting quick intervention. Measurements of the terrestrial gamma radiation exposure have been carried out in the environments of major industries in Ota using a portable survey meter. The motivation for this study resulted from the uncertainty in the general public opinion on the effect of the presence, and activities of some of these industries in their environment. Measurements were taken twice daily within the vicinity of each industry to determine the dose levels. The mean values obtained range from 0.11 – 1.80 µSv/h. These values are within the results obtained from normal background areas except for site number 10. Annual effective dose values range from 0.25 – 5.21 mSv with a mean value of 1.21 mSv. Routine activities in some of these environments may have contributed significantly to the ambient natural background radiation resulting in high values as obtained in some of these locations. The total risks disparately estimated for cancer and genetic effects resulting from the results obtained range from 0.17 x 10-4 – 3.80 x 10-4 with a mean value of 0.94 x 10-4. These levels are within the range of the average annual risk for accidental death for all industries.

  14. Monitoring of radiation in the environment in the Netherlands. Results in 2002

    NARCIS (Netherlands)

    Knetsch GJ; RIZA; RIKZ; KvW; LSO; IMD

    2004-01-01

    The Dutch government is compelled to measure radioactivity in the environment under terms of the Euratom Treaty of 1957. This report presents the results of radioactivity measurements in the Dutch environment in 2002. The measurements were carried out by RIVM, RIZA, RIKZ and Inspectorate for Health

  15. Ultraviolet radiation and primary productivity in temperate aquatic environments of Patagonia (Argentina)

    NARCIS (Netherlands)

    Villafañe, Virginia

    2004-01-01

    Numerous studies carried out since the discovery of the ozone “hole” over the Antarctic continent have motivated photobiological research to determine the potential effects of increased solar ultraviolet radiation – UV-B (280-315 nm) on organisms and ecosystems. Since then, the amount of literature

  16. Modelling radiation fluxes in simple and complex environments--application of the RayMan model.

    Science.gov (United States)

    Matzarakis, Andreas; Rutz, Frank; Mayer, Helmut

    2007-03-01

    The most important meteorological parameter affecting the human energy balance during sunny weather conditions is the mean radiant temperature T(mrt). It considers the uniform temperature of a surrounding surface giving off blackbody radiation, which results in the same energy gain of a human body given the prevailing radiation fluxes. This energy gain usually varies considerably in open space conditions. In this paper, the model 'RayMan', used for the calculation of short- and long-wave radiation fluxes on the human body, is presented. The model, which takes complex urban structures into account, is suitable for several applications in urban areas such as urban planning and street design. The final output of the model is, however, the calculated T(mrt), which is required in the human energy balance model, and thus also for the assessment of the urban bioclimate, with the use of thermal indices such as predicted mean vote (PMV), physiologically equivalent temperature (PET) and standard effective temperature (SET*). The model has been developed based on the German VDI-Guidelines 3789, Part II (environmental meteorology, interactions between atmosphere and surfaces; calculation of short- and long-wave radiation) and VDI-3787 (environmental meteorology, methods for the human-biometeorological evaluation of climate and air quality for urban and regional planning. Part I: climate). The validation of the results of the RayMan model agrees with similar results obtained from experimental studies.

  17. Methodology Development for SiC Sensor Signal Modelling in the Nuclear Reactor Radiation Environments

    International Nuclear Information System (INIS)

    Cetnar, J.; Krolikowski, I.P.

    2013-06-01

    This paper deals with SiC detector simulation methodology for signal formation by neutrons and induced secondary radiation as well as its inverse interpretation. The primary goal is to achieve the SiC capability of simultaneous spectroscopic measurements of neutrons and gamma-rays for which an appropriate methodology of the detector signal modelling and its interpretation must be adopted. The process of detector simulation is divided into two basically separate but actually interconnected sections. The first one is the forward simulation of detector signal formation in the field of the primary neutron and secondary radiations, whereas the second one is the inverse problem of finding a representation of the primary radiation, based on the measured detector signals. The applied methodology under development is based on the Monte Carlo description of radiation transport and analysis of the reactor physics. The methodology of SiC detector signal interpretation will be based on the existing experience in neutron metrology developed in the past for various neutron and gamma-ray detection systems. Since the novel sensors based on SiC are characterised by a new structure, yet to be finally designed, the methodology for particle spectroscopic fluence measurement must be developed while giving a productive feed back to the designing process of SiC sensor, in order to arrive at the best possible design. (authors)

  18. Evaluation of cryogenic insulation materials and composites for use in nuclear radiation environments

    Science.gov (United States)

    Bullock, R. E.

    1972-01-01

    The following subjects are studied: (1) composite materials tests; (2) test of liquid level sensors and fission couples; (3) test of valve-seal materials; (4) boron epoxy composites; (5) radiation analysis of explosive materials and bifuels for RNS applications; and (6) test of thermal insulation.

  19. THE EFFECT OF SOLAR RADIATION ON AUTOMOBILE ENVIRONMENT THROUGH NATURAL CONVECTION AND MIXED CONVECTION

    Directory of Open Access Journals (Sweden)

    MD. FAISAL KADER

    2012-10-01

    Full Text Available In the present paper, the effect of solar radiation on automobiles has been studied by both experimentally and numerically. The numerical solution is done by an operation friendly and fast CFD code – SC/Tetra with a full scale model of a SM3 car and turbulence is modeled by the standard k-ε equation. Numerical analysis of the three-dimensional model predicts a detailed description of fluid flow and temperature distribution in the passenger compartment during both the natural convection due to the incoming solar radiation and mixed convection due to the flow from defrost nozzle and radiation. It can be seen that solar radiation is an important parameter to raise the compartment temperature above the ambient temperature during summer. During natural convection, the rate of heat transfer is fast at the initial period. In the mixed convection analyses, it is found that the temperature drops down to a comfortable range almost linearly at the initial stage. Experimental investigations are performed to determine the temperature contour on the windshield and the local temperature at a particular point for further validation of the numerical results.

  20. Star tracker and vision systems performance in a high radiation environment

    DEFF Research Database (Denmark)

    Jørgensen, John Leif; Riis, Troels; Betto, Maurizio

    1999-01-01

    A part of the payload of the second Ariane 5 prototype vehicle to be launched by Arianespace, was a small technology demonstration satellite. On October 30th, 1997, this test satellite, dubbed Teamsat, was launched into Geostationary Transfer Orbit and would as such pass the Van Allen radiation b...

  1. Development of MAAP5.0.3 Dose Model for Radiation Environment Effect Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Mi Ro [KHNP-CRI, Daejeon (Korea, Republic of)

    2015-10-15

    The equipment survivability assessment under the severe accident conditions should be performed. For the environmental conditions such as the pressure and temperature, they can be calculated using MAAP (Modular Accident Analysis Program) code. However, since MAAP itself cannot calculate the radiation DOSE, MAAP5 DOSE model should be developed in order to calculate the DOSE rate during the severe accidents. In this study, we developed the MAAP5 DOSE model for spent fuel pool of OPR1000 type NPP and calculated the DOSE to assess the survivability of the facilities in spent fuel pool and fuel handling region. Until now, there are so many uncertainties in the analysis for radiation effect during the severe accident. However, in terms of the establishment of the severe accident management strategy, quantitative analysis in order to find the general trend for radiation increase during the severe accident is useful. For the radiation environmental effect analysis, the previous studies are mainly focused inside the containment. However, after the Fukushima accident, the severe accident phenomena in the SFP have been the great issues in the nuclear industry including Korea. So, in this study, the dose rate for spent fuel building when the severe accident happens in the SFP is calculated using MAAP5 DOSE. As expected, the dose rate is increased right after the spent fuel is partially uncovered. However, the amount of dose is less significant since the rate of temperature increase is much faster than the rate of dose increase.

  2. Evaluation of the environmental quality objective 'A Safe Radiation Environment'; Utvaerdering av miljoekvalitetsmaalet 'Saeker straalmiljoe'

    Energy Technology Data Exchange (ETDEWEB)

    Asp, Helene; Brewitz, Erica; Halvarsson, Andreas; Ljungberg, Sophie; Mjoenes, Lars; Wallberg, Petra

    2007-11-15

    The evaluation of the environmental quality objective 'A Safe Radiation Environment' is a contribution to the Environmental Objective Council's assessment of progress towards the national environmental quality objectives. The report describes and evaluates the radiation environment in Sweden, the regulatory instruments, measures carried out and the monitoring programmes. Furthermore, the possibility of achieving the objective and its interim targets is evaluated. New measures and means of control are proposed. The proposals are directed to the government and Parliament, national authorities and other stakeholders in society. The Swedish Radiation Protection Authority (SSI) considers it possible to achieve the objective, but additional efforts are required to ensure success. Environmental monitoring, research on health effects of radiation and supervision are still important areas. Intensified efforts will be needed to change attitudes towards suntanning. Changes in the formulation of the objective and its interim targets are suggested. Today only protection against radiation in the external environment is covered by the objective. Radiation protection work has to consider all. SSI therefore suggests that the objective should extend to include workplaces and indoor environment. For the three interim targets included in 'A Safe Radiation Environment', changes are suggested for the interim targets for radioactive substances and electromagnetic fields. No change is suggested for the interim target for skin cancer

  3. Apollo Lunar Astronauts Show Higher Cardiovascular Disease Mortality: Possible Deep Space Radiation Effects on the Vascular Endothelium.

    Science.gov (United States)

    Delp, Michael D; Charvat, Jacqueline M; Limoli, Charles L; Globus, Ruth K; Ghosh, Payal

    2016-07-28

    As multiple spacefaring nations contemplate extended manned missions to Mars and the Moon, health risks could be elevated as travel goes beyond the Earth's protective magnetosphere into the more intense deep space radiation environment. The primary purpose of this study was to determine whether mortality rates due to cardiovascular disease (CVD), cancer, accidents and all other causes of death differ in (1) astronauts who never flew orbital missions in space, (2) astronauts who flew only in low Earth orbit (LEO), and (3) Apollo lunar astronauts, the only humans to have traveled beyond Earth's magnetosphere. Results show there were no differences in CVD mortality rate between non-flight (9%) and LEO (11%) astronauts. However, the CVD mortality rate among Apollo lunar astronauts (43%) was 4-5 times higher than in non-flight and LEO astronauts. To test a possible mechanistic basis for these findings, a secondary purpose was to determine the long-term effects of simulated weightlessness and space-relevant total-body irradiation on vascular responsiveness in mice. The results demonstrate that space-relevant irradiation induces a sustained vascular endothelial cell dysfunction. Such impairment is known to lead to occlusive artery disease, and may be an important risk factor for CVD among astronauts exposed to deep space radiation.

  4. Mathematical modeling of heat transfer between the plant seedling and the environment during a radiation frost

    Directory of Open Access Journals (Sweden)

    Finnikov K.A.

    2010-11-01

    Full Text Available The power of the internal heat source sufficient to maintain a positive temperature of plants during one of the possible form of cold stress - radiation frost was determined with the help of numerical simulation.The simulation of unsteady heat transfer in the soil-plant-air system in the conditions of radiation frost showed that the the ground part of plants is cooling most rapidly, and this process is partially slowed down by the natural-convection heat transfer with warmer air. If the frost is not continuous, the radiative cooling is the main danger for plant. The necessary power of heat-production inside plant that allows it to avoid hypothermia depends both on natural conditions and the size of the plant. For plants with a typical diameter of the stem about 2 mm this heat-production should be from 50 to 100 W / kg. Within 2 hours a total amount of heat about 0.5 MJ / kg in the plant should be allocated. Larger plants will have a smaller surface to mass ratio, and the maintaining of it's temperature will require a lower cost of nutrients per unit, accordingly. Modeling of the influence of plant surface trichomes presence on the process of its cooling showed that the role of trichomes in the protection of plants from hypothermia during radiation frost usually is negative due to the fact that the presence of trichomes increases the radiative heat transfer from the plant and the impediment in air movement near the plant reduces heat flux entering the plant from a warmer air. But in cases where the intensity of heat generation within the plant is sufficient for the maintenance of the plant temperature higher than the air temperature, the presence of trichomes impairs heat transfer from plant to air, and therefore contributes to a better heating of plants.

  5. Impact of low-level radiation with special reference to tritium in environment

    International Nuclear Information System (INIS)

    Bhatia, A.L.

    2005-01-01

    Radiation is invisible, but exists in various types, in the form of particles and/or energy bundles. The effects of low-level radiation seem very abstract since these can not be perceived by our sensory organs. The increase in natural background radiation from various inadvertent sources like tritium has the prospect of altering the entire scenario of billions of years' slow and steady biogenetic evolution. Mankind, by developing atomic technologies, is unleashing forces which it does understand but not beyond experimental findings. There is no wise sorcerer who can undo the damage we are causing. Tritium is a radioactive form of hydrogen that is produced in the reactor core. The released tritium replaces hydrogen in water. Tritium in water when gets ingested, causes continuos internal low-level beta radiation exposure over a long period. Proposed presentation will focus on the possible long term damage caused by its low-level exposure is dependent on the length of duration living tissue spends in the radiation field, not on the relative radiation field strength. As internal radiation pulses never stop, impact is continuous by the ambient radiation atmosphere. There is no chance to heal at the molecular level, except small chances of DNA repair since the organically bound tritium has greater severe influence with the slow turnover. Though the situation needs not be alarming with tritium, the studies on radiation damage on various parameters have given evidence of two compartments of radiation damage; the reparable or potentially lethal and the irreparable or lethal. With emerging new reports on the stochastic effects, those for which the probability, rather than the severity of an effect from tritium occurring as a function of dose also can not be ruled out. Biotoxicity of tritium in the form of induction of cancer, hereditary effects, teratogenesis and life shortening really needs an exhaustive investigation and warrants careful evaluation. However, a positive

  6. Impact of reflecting land surface on radiation environment over Hornsund, Spitsbergen – a model study for cloudless skies

    Directory of Open Access Journals (Sweden)

    Rozwadowska Anna

    2017-06-01

    Full Text Available This paper addresses the influence of land topography and cover on 3D radiative effects under cloudless skies in the Hornsund area, Spitsbergen, Svalbard. The authors used Monte Carlo simulations of solar radiation transfer over a heterogeneous surface to study the impact of a non-uniform surface on: (1 the spatial distribution of irradiance transmittance at the fjord surface under cloudless skies; (2 the spectral shortwave aerosol radiative forcing at the fjord surface; (3 normalized nadir radiance at the Top Of the Atmosphere (TOA over the fjord. The modelled transmittances and radiances over the fjord are compared to the transmittances and radiances over the open ocean under the same conditions. The dependence of the 3D radiative effects on aerosol optical thickness, aerosol type, surface albedo distribution, solar azimuth and zenith angle and spectral channel is discussed. The analysis was done for channels 3 (459-479 nm and 2 (841-876 nm of the MODIS radiometer. In the simulations a flat water surface was assumed. The study shows that snow-covered land surrounding the fjord strongly modifies the radiation environment over the fjord surface. The enhancement of the mean irradiance transmittance over the fjord with respect to the open ocean is up to 0.06 for channel 3. The enhancement exceeds 0.11 in the vicinity of sunlit cliffs. The influence of the snow-covered land on the TOA radiance over the fjord in channel 3 is comparable to the impact of an increase in aerosol optical thickness of over 100%, and in lateral fjords of up to several hundred percent. The increase in TOA radiance is wavelength dependent. These effects may affect retrievals of aerosol optical thickness.

  7. An overview of the radiation environment at the LHC in light of R2E irradiation test activities

    CERN Document Server

    Roeed, K; Spiezia, G; CERN. Geneva. ATS Department

    2011-01-01

    The main objective of this report is to present a brief overview of the radiation environment that can be expected in areas where electronics is installed in the LHC. This covers particle energy spectra in addition to nominal integrated values of the High Energy Hadron (HEH) fluence, relevant for Single Event Effects (SEEs), Total Ionizing Dose (TID), and the 1 MeV neutron equivalent, relevant for displacement damage. The risk of thermal neutrons is considered by introducing the risk factor Rth. This report is presented as part of the R2E project and should create a foundation from which appropriate irradiation test criteria can be evaluated and determined.

  8. Comments on the paper 'Radiation doses from iodine-129 in the environment' by J.K. Soldat

    International Nuclear Information System (INIS)

    Thompson, J.C. Jr.

    1976-01-01

    Reference is made to a recent article by Soldat entitled 'Radiation Doses from 129 I in the Environment' (Health Phys. Jan 1976) in which it is claimed that human and bovine consumption estimates were used in arriving at 129 I thyroid doses which do not conform to observed consumption data. It is claimed that the disparity between the consumption data for milk, leafy vegetable and beef and the feed intake estimates for beef cattle is sufficient to produce 129 I thyroid dose estimates that are considerably elevated. Using consumption data here advocated a modified table of thyroid dose estimates from unit concentrations of 129 I in air is presented. (U.K.)

  9. Computer simulation of spacecraft/environment interaction

    CERN Document Server

    Krupnikov, K K; Mileev, V N; Novikov, L S; Sinolits, V V

    1999-01-01

    This report presents some examples of a computer simulation of spacecraft interaction with space environment. We analysed a set data on electron and ion fluxes measured in 1991-1994 on geostationary satellite GORIZONT-35. The influence of spacecraft eclipse and device eclipse by solar-cell panel on spacecraft charging was investigated. A simple method was developed for an estimation of spacecraft potentials in LEO. Effects of various particle flux impact and spacecraft orientation are discussed. A computer engineering model for a calculation of space radiation is presented. This model is used as a client/server model with WWW interface, including spacecraft model description and results representation based on the virtual reality markup language.

  10. Computer simulation of spacecraft/environment interaction

    International Nuclear Information System (INIS)

    Krupnikov, K.K.; Makletsov, A.A.; Mileev, V.N.; Novikov, L.S.; Sinolits, V.V.

    1999-01-01

    This report presents some examples of a computer simulation of spacecraft interaction with space environment. We analysed a set data on electron and ion fluxes measured in 1991-1994 on geostationary satellite GORIZONT-35. The influence of spacecraft eclipse and device eclipse by solar-cell panel on spacecraft charging was investigated. A simple method was developed for an estimation of spacecraft potentials in LEO. Effects of various particle flux impact and spacecraft orientation are discussed. A computer engineering model for a calculation of space radiation is presented. This model is used as a client/server model with WWW interface, including spacecraft model description and results representation based on the virtual reality markup language

  11. Radiation Hardened High Speed Fiber Optic Transceivers for Extreme Environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose the development of transceiver offering wide bandwidth (1 Mbps to 10 Gbps) that operates in space environments targeted by NASA for robotic exploration....

  12. Radiation Hardened High Speed Fiber Optic Transceivers for Extreme Environments, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This program develops fiber optic transceivers that offer wide bandwidth (1 Mbps to 10 Gbps) and operate in space environments targeted by NASA for robotic...

  13. Radiation Hardened High Speed Integrated Circuits SERDES I/O for Extreme Operating Environments, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Manned and robotic space missions require high-performance electronic control systems capable of operating for extended periods in harsh environments subject to...

  14. High Intensity Radiated Field External Environments for Civil Aircraft Operating in the United States of America

    National Research Council Canada - National Science Library

    Heather, Frederick

    2002-01-01

    ... (FAR) Parts 23, 25, 27, and 29. The HIRF survey determined the Rotorcraft Severe, Fixed Wing Severe, Certification, and Normal Environments that civil aircraft may be exposed to while operating in the continental U.S...

  15. High Intensity Radiated Field External Environments for Civil Aircraft Operating in the United States of America

    National Research Council Canada - National Science Library

    Heather, Frederick

    1998-01-01

    ...) Parts 23, 25, 27, and 29. The HIRF survey determined the Rotorcraft Severe, Fixed Wing Severe, Certification, and Normal Environments that civil aircraft may be exposed to while operating in the continental U.S...

  16. Cosmic-ray-induced radiation environment and dose to man for low-orbit space applications

    International Nuclear Information System (INIS)

    Sandmeier, H.A.; Hansen, G.E.; Battat, M.E.; O'Brien, K.

    1981-09-01

    Neutrons and photons resulting from the interaction of galactic cosmic rays with the material of an orbiting satellite or an orbiting space station at an altitude of some few hundreds of kilometers, and below the level of the radiation belts, have been calculated as a function of geomagnetic latitude and solar activity level. The photon and neutron leakage currents from the top of the atmosphere have been computed. The radiation dose-equivalent rate to an unshielded astronaut has also been calculated. The maximum dose-equivalent rate, near the magnetic poles, was 2 mrem/h. In deep space this would amount to 18 rem/y, indicating that for a prolonged stay in space, shielding would be needed

  17. Surface effects on tritium diffusion in materials in a radiation environment

    International Nuclear Information System (INIS)

    Caskey, G.R. Jr.

    1975-01-01

    Tritium transport and distribution in a material are controlled by chemical potential and thermal gradients and cross-coupling to impurities and defects. Surfaces influence tritium diffusion by acting as sources and sinks for defects and impurities, and surface films restricting tritium transfer between the solid and surrounding fluids. Radiation directly affects boundary processes such as dissociation or adsorption, may erode a surface film or the surface itself, and introduces defects and impurities into the solid by radiation damage, transmutation, or ion implantation, thereby modifying tritium transport within the solid and its transfer across external interfaces. There have been no definitive investigations of these effects, but their practical significance has been demonstrated in tritium release or absorption studies with stainless steel, Zircaloy, niobium, and other materials. (auth)

  18. Radiation protection and environment day the low doses in everyday life

    International Nuclear Information System (INIS)

    2007-01-01

    The consequences of low doses exposures are difficult to explore and the studies give often place to controversies. According to the are, differences exist in the methodological approaches. It results from it a confusion on the acceptable levels of exposure, even on the definition of low dose. This day organised by the sections 'non ionizing and research and health of the French society of radiation protection (S.F.R.P.), will be a meeting between professionals of different disciplines, to compare the approaches used for the ionizing and non ionizing radiations as well as the chemical and microbiological agents. It will allow to share the knowledge and the abilities and to progress on methodologies adapted to the evaluation and the management of risks in relation with low doses. (N.C.)

  19. Monitoring of radiation in the environment in the Netherlands. Results in 2001

    CERN Document Server

    Knetsch, G J

    2002-01-01

    This report presents the results of radioactivity measurements in the Dutch environment in 2001. The measurements were carried out by RIVM, RIZA, RIKZ and Inspectorate for Health Protection and Veterinary Public Health. Radioactivity measurements were carried out on airborne particles, deposition, surface water, seawater, drinking water and food (honey, powdered milk, game, poultry, blueberry and chanterelle). Results for ambient dose equivalent rates were obtained from the National Radioactivity Monitoring Network. The levels of radioactivity in the Dutch environment were not elevated in 2001

  20. Monitoring of radiation in the environment in the Netherlands. Results in 2001

    Energy Technology Data Exchange (ETDEWEB)

    Knetsch, G.J. (ed.)

    2002-07-01

    This report presents the results of radioactivity measurements in the Dutch environment in 2001. The measurements were carried out by RIVM, RIZA, RIKZ and Inspectorate for Health Protection and Veterinary Public Health. Radioactivity measurements were carried out on airborne particles, deposition, surface water, seawater, drinking water and food (honey, powdered milk, game, poultry, blueberry and chanterelle). Results for ambient dose equivalent rates were obtained from the National Radioactivity Monitoring Network. The levels of radioactivity in the Dutch environment were not elevated in 2001.

  1. Radiation Protection Research: Radon in the Indoor Environment and enhanced natural radioactivity

    International Nuclear Information System (INIS)

    Paridaens, J.

    2000-01-01

    The objectives of R and D on epidemiological studies concerning radon related to health risks at SCK-CEN is to (1) to apply new techniques for retrospective radon measurements in real field conditions and to assess radon decay product exposure by combining these techniques; and (2) to increase capabilities in mapping and surveying sites possibly or likely contaminated with enhanced levels of natural radiation. Progress and main achievements in 1999 are reported on

  2. An assessment of aquatic radiation pathways in Ireland, 2008 Environment Report RL 16/08

    International Nuclear Information System (INIS)

    Clyne, F.J.; Garrod, C.J.; Jeffs, T.M; Jenkinson, S.B

    2009-05-01

    This report provides an assessment of aquatic radiation exposure pathways in Ireland relating to anthropogenic radioactivity in the Irish Sea. It comprises the results of a habits survey undertaken on the north east coast of Ireland; a dose assessment using the habits survey data; 2007 monitoring data provided by the RPII; and recommendations for changes to the 2007 east coast of Ireland marine monitoring programme conducted by the RPII

  3. PRIMA Platform capability for satellite missions in LEO and MEO (SAR, Optical, GNSS, TLC, etc.)

    Science.gov (United States)

    Logue, T.; L'Abbate, M.

    2016-12-01

    PRIMA (Piattaforma Riconfigurabile Italiana Multi Applicativa) is a multi-mission 3-axis stabilized Platform developed by Thales Alenia Space Italia under ASI contract.PRIMA is designed to operate for a wide variety of applications from LEO, MEO up to GEO and for different classes of satellites Platform Family. It has an extensive heritage in flight heritage (LEO and MEO Satellites already fully operational) in which it has successfully demonstrated the flexibility of use, low management costs and the ability to adapt to changing operational conditions.The flexibility and modularity of PRIMA provides unique capability to satisfy different Payload design and mission requirements, thanks to the utilization of recurrent adaptable modules (Service Module-SVM, Propulsion Module-PPM, Payload Module-PLM) to obtain mission dependent configuration. PRIMA product line development is continuously progressing, and is based on state of art technology, modular architecture and an Integrated Avionics. The aim is to maintain and extent multi-mission capabilities to operate in different environments (LEO to GEO) with different payloads (SAR, Optical, GNSS, TLC, etc.). The design is compatible with a wide range of European and US equipment suppliers, thus maximising cooperation opportunity. Evolution activities are mainly focused on the following areas: Structure: to enable Spacecraft configurations for multiple launch; Thermal Control: to guarantee thermal limits for new missions, more demanding in terms of environment and payload; Electrical: to cope with higher power demand (e.g. electrical propulsion, wide range of payloads, etc.) considering orbital environment (e.g. lighting condition); Avionics : AOCS solutions optimized on mission (LEO observation driven by agility and pointing, agility not a driver for GEO). Use of sensors and actuators tailored for specific mission and related environments. Optimised Propulsion control. Data Handling, SW and FDIR mission customization

  4. Grid2: A Program for Rapid Estimation of the Jovian Radiation Environment

    Science.gov (United States)

    Evans, R. W.; Brinza, D. E.

    2014-01-01

    Grid2 is a program that utilizes the Galileo Interim Radiation Electron model 2 (GIRE2) Jovian radiation model to compute fluences and doses for Jupiter missions. (Note: The iterations of these two softwares have been GIRE and GIRE2; likewise Grid and Grid2.) While GIRE2 is an important improvement over the original GIRE radiation model, the GIRE2 model can take as long as a day or more to compute these quantities for a complete mission. Grid2 fits the results of the detailed GIRE2 code with a set of grids in local time and position thereby greatly speeding up the execution of the model-minutes as opposed to days. The Grid2 model covers the time period from 1971 to 2050 and distances of 1.03 to 30 Jovian diameters (Rj). It is available as a direct-access database through a FORTRAN interface program. The new database is only slightly larger than the original grid version: 1.5 gigabytes (GB) versus 1.2 GB.

  5. Feasibility Study for a Combined Radiation Environment in the ACRR-FRECII Cavity.

    Energy Technology Data Exchange (ETDEWEB)

    Parma, Edward J.

    2017-12-01

    The objective of this report is to determine the feasibility of a combined pulsed - power accelerator machine, similar to HERMES - III, with the Annular Core Research Reactor (ACRR) Fueled - Ring External Cavity (FREC - II) in a new facility. The document is conceptual in nature, and includes some neutronic analysis that i llustrates that that the physics of such a concept would be feasible. There would still be many engineering design considerations and issues that would need to be investigated in order to determine the true viability of such a concept. This report does n ot address engineering design details, the cost of such a facility, or what would be required to develop the safety authorization of the concept. The radiation requirements for the "on - target" gamma - ray dose and dose rate are not addressed in this report . It is assumed that if the same general on - target specifications for a HERMES - III type machine could be met with the proposed concept, that the machine would b e considered highly useful as a radiation effects sciences platform. In general, the combined accelerator/ACRR reactor concept can be shown to be feasible with no major issues that would preclude the usefulness of such a facility. The new facility would provide a capability that currently does not exist in the radiation testing complex.

  6. Radiation state of environment in the 30-km zone of Chernobyl NPP, water objects

    International Nuclear Information System (INIS)

    Sukhoruchkin, A.K.

    1994-01-01

    The level of radioactivity in the zone of Chernobyl NPP before the accident is shown. The extremely high level of radioactive contamination produced by the release from the ChNPP at the accident declined as short-lived nuclides decayed. The aerial γ surveys of the 5 km zone of the ChNPP in October, 1986 and September, 1987 are shown. The radiation hygienic parameters of long-lived nuclides at the moment of release are presented. The main contribution to the dose in inhalation is expected from transuranium nuclides, and in ingestion, 90 Sr. The radiation situation in the 30 km zone is at present determined by 137 Cs, 90 Sr and transuranium nuclides, and such nuclide mixture is very unfavorable from the radiobiological point of view. The dosimetric monitoring of them is discussed. The soil contamination density in the 5 km zone is shown. The circumstances of the rich water resources in the region are explained, and the state of contamination is shown. The observation of radioactive contamination of the surface water of Pripyat River is described, and the results are shown. Much concern in the 30 km zone was aroused by the radiation state of groundwater at the places of the forced temporary burial of solid radioactive waste. The state of the cooling water pond in relation to Pripyat River is reported. (K.I.)

  7. Failure modes induced by natural radiation environments on DRAM memories: study, test methodology and mitigation technique

    International Nuclear Information System (INIS)

    Bougerol, A.

    2011-05-01

    DRAMs are frequently used in space and aeronautic systems. Their sensitivity to cosmic radiations have to be known in order to satisfy reliability requirements for critical applications. These evaluations are traditionally done with particle accelerators. However, devices become more complex with technology integration. Therefore new effects appear, inducing longer and more expensive tests. There is a complementary solution: the pulsed laser, which triggers similar effects as particles. Thanks to these two test tools, main DRAM radiation failure modes were studied: SEUs (Single Event Upset) in memory blocks, and SEFIs (Single Event Functional Interrupt) in peripheral circuits. This work demonstrates the influence of test patterns on SEU and SEFI sensitivities depending on technology used. In addition, this study identifies the origin of the most frequent type of SEFIs. Moreover, laser techniques were developed to quantify sensitive surfaces of the different effects. This work led to a new test methodology for industry, in order to optimize test cost and efficiency using both pulsed laser beams and particle accelerators. Finally, a new fault tolerant technique is proposed: based on DRAM cell radiation immunity when discharged, this technique allows to correct all bits of a logic word. (author)

  8. Radiation resistance of lactobacilli isolated from radurized meat relative to growth and environment

    International Nuclear Information System (INIS)

    Hastings, J.W.; Holzapfel, W.H.; Niemand, J.G.

    1986-01-01

    Of 113 lactobacilli isolated from radurized (5 kGy) minced meat, 7 Lactobacillus sake strains, 1 L. curvatus strain, and 1 L. farciminis strain were used for radiation resistance studies in a semisynthetic substrate (i.e., modified MRS broth). Five reference Lactobacillus spp. one Staphylococcus aureus strain, and one Salmonella typhimurium strain were used for comparative purposes. All L. sake isolates exhibited the phenomenon of being more resistant to gamma-irradiation in the exponential (log) phase than in the stationary phase of their growth cycles by a factor of 28%. Four reference strains also exhibited this phenomenon, with L. sake (DSM 20017) showing a 68% increase in resistance in the log phase over the stationary phase. This phenomenon was not common to all bacteria tested and is not common to all strains with high radiation resistance. Four L. sake isolates and three reference strains were used in radiation sensitivity testing in a natural food system (i.e., meat). The bacteria were irradiated in minced meat and packaged under four different conditions (air, vacuum, CO 2 , and N 2 ). Organisms exhibited the highest death rate (lowest D 10 values [doses required to reduce the logarithm of the bacterial population by 1] under CO 2 packaging conditions, but resistance to irradiation was increased under N 2 . The D 10 values of the isolates were generally greater than those of the reference strains. The D 10 values were also higher (approximately two times) in meat than in a semisynthetic growth medium

  9. Monte Carlo simulation of muon radiation environment in China Jinping Underground Laboratory

    International Nuclear Information System (INIS)

    Su Jian; Zeng Zhi; Liu Yue; Yue Qian; Ma Hao; Cheng Jianping

    2012-01-01

    Muon radiation background of China Jinping Underground Laboratory (CJPL) was simulated by Monte Carlo method. According to the Gaisser formula and the MUSIC soft, the model of cosmic ray muons was established. Then the yield and the average energy of muon-induced photons and muon-induced neutrons were simulated by FLUKA. With the single-energy approximation, the contribution to the radiation background of shielding structure by secondary photons and neutrons was evaluated. The estimation results show that the average energy of residual muons is 369 GeV and the flux is 3.17 × 10 -6 m -2 · s -1 . The fluence rate of secondary photons is about 1.57 × 10 -4 m -2 · s -1 , and the fluence rate of secondary neutrons is about 8.37 × 10 -7 m -2 · s -1 . The muon radiation background of CJPL is lower than those of most other underground laboratories in the world. (authors)

  10. Inconsistencies in net radiation estimates from use of several models of instruments in a desert environment

    International Nuclear Information System (INIS)

    Kustas, W.P.; Prueger, J.H.; Hipps, L.E.; Hatfield, J.L.; Meek, D.

    1998-01-01

    Studies of surface energy and water balance generally require an accurate estimate of net radiation and its spatial distribution. A project quantifying both short term and seasonal water use of shrub and grass vegetation in the Jornada Experimental Range in New Mexico prompted a study to compare net radiation observations using two types of net radiometers currently being used in research. A set of 12 REBS net radiometers were compared with each other and one Swissteco, over wet and dry surfaces in an arid landscape under clear skies. The set of REBS exhibited significant differences in output over both surfaces. However, they could be cross calibrated to yield values within 10 W m −2 , on average. There was also a significant bias between the REBS and Swissteco over a dry surface, but not over a wet one. The two makes of instrument could be made to agree under the dry conditions by using regression or autoregression techniques. However, the resulting equations would induce bias for the wet surface condition. Thus, it is not possible to cross calibrate these two makes of radiometer over the range of environmental conditions observed. This result indicates that determination of spatial distribution of net radiation over a variable surface should be made with identical instruments which have been cross calibrated. The need still exists for development of a radiometer and calibration procedures which will produce accurate and consistent measurements over a range of surface conditions. (author)

  11. On protection of freedom's solar dynamic radiator from the orbital debris environment. Part 1

    International Nuclear Information System (INIS)

    Rhatigan, J.L.

    1992-01-01

    A great deal of experimentation and analysis has been performed to quantify penetration thresholds of components which will experience orbital debris impacts. Penetration has been found to depend upon mission-specific parameters such as orbital altitude, inclination, and orientation of the component; and upon component specific parameters such as material, density, and the geometry particular to its shielding. Experimental results are highly dependent upon shield configuration and cannot be extrapolated with confidence to alternate shield configurations. Also, current experimental capabilities are limited to velocities which only approach the lower limit of predicted orbital debris velocities. Therefore, prediction of the penetrating particle size for a particular component having a complex geometry remains highly uncertain. This paper describes the approach developed to assess on-orbit survivability, and include the type of particle and particle population expected to defeat the radiator bumpering (i.e., penetrate a fluid flow tube). Results of preliminary hypervelocity impact testing performed on radiator panel samples (in the 6 to 7 km/sec velocity range) are also presented. Plans for further analyses and testing are discussed. These efforts are expected to lead to a radiator design which will perform to Space Station Freedom requirements over the expected lifetime

  12. Research And Investigation To Establish The Database Of Environment Radiation Background For Vietnam (Phase 2009 -2011)

    International Nuclear Information System (INIS)

    Trinh Van Giap; Nguyen Huu Quyet; Nguyen Quang Long; Bui Dac Dung; Vuong Thu Bac; Le Dinh Cuong; Chu Vu Long; Le Ngoc Thiem; Truong Y; Nguyen Van Mai; Nguyen Ba Tien

    2013-01-01

    Setting up data base of natural radiation background serves for planning socio-economics development in a province as well as the whole country and estimating annual effective dose of population. Beside external irradiation dose caused by the natural radioisotopes in the series 238 U, 232 Th and 40 K in soil, population has been received internal dose caused by the above radioisotopes taken in the body from several ways. In order to complete the database of national radiation background and go to estimate annual effective radiation dose of population in the whole country, this project focus to carry out the works as following: (i) Setting up database of radiation background in the whole country: 150 soil samples that collected in the districts of 46 provinces have been analyzed. The average activity concentration of 238 U, 232 Th and 40 K are 37.86 Bq/kg, 58.88 Bq/kg and 462.78 Bq/kg, respectively. The outdoor, indoor and total annual effective doses are calculated: 0.087±0.036 mSv; 0.488±0.202 mSv and 0.576± 0.240 mSv, respectively. (ii) Setting up database of radiation background of province Ninh Thuan and Quang Nam: The detailed database of radiation background of all villages in Ninh Thuan and Quang Nam has been established. 84 soil samples in Ninh Thuan and 311 in Quang Nam were collected for analyze. The indoor and outdoor radon concentration at sampling positions has been measured. The average activities of 238 U, 232 Th, 40 K, and 222 Rn isotopes in Ninh Thuan are reported: 33.50 Bq/kg, 55.43 Bq/kg, 701.12 Bq/kg and 12.1 Bq/m 3 , 9.5 Bq/m 3 , respectively. The outdoor, indoor and total annual effective doses in Ninh Thuan are calculated: 0.095±0.029 mSv; 0.529±0.162 mSv and 0.624± 0.382 mSv, respectively. The average activities of 238 U, 232 Th, 40 K, and 222 Rn isotopes in Quang Nam are reported: 44.47 Bq/kg, 52.68 Bq/kg, 459.33 Bq/kg, 18.0 Bq/m 3 . The outdoor, indoor and total annual effective doses are calculated: 0.086±0.039 mSv; 0.482±0.216 m

  13. Preliminary Results for the Radiation Environment Observed by RD3-B3 Radiometerdosimeter Inside Bion-M # 1 Spacecraft

    Science.gov (United States)

    Dachev, Tsvetan; Tomov, Borislav; Matviichuk, Yury; Dimitrov, Plamen; Bankov, Nikolay; Petrov, Vladisloav; Shurshakov, Viacheslav; Ivanova, Olga; Häder, Donat-Peter; Lebert, Michael; Schuster, Martin; Reitz, Günter; Horneck, Gerda; Ploc, Ondrej

    2013-12-01

    Space radiation has been monitored using the P#xd0bb;3-킑3 (further is used the Latin transcription RD3-B3) spectrometer-dosimeter on board a recent space flight on the Russian recoverable satellite 킑킍OH-M No.1 (further is used the Latin transcription BIONM No. 1). The instrument was mounted inside of the satellite in pressurized volume together with biological objects and samples. RD3-B3 instrument is a battery operated version of the spare model of the R3D-B3 instrument developed and built for the ESA BIOPAN-6 facility on Foton M3 satellite flown in September 2007. Cosmic ionizing radiation has been monitored and separated in 256 deposited energy spectra, which were further used for determination of the absorbed dose rate and flux. The report summarizes the first results for the Earth radiation environment at the altitude (253-585 km) of the BION-M No.1 spacecraft.

  14. Design of a MGy radiation tolerant resolver-to-digital convertor IC for remotely operated maintenance in harsh environments

    Energy Technology Data Exchange (ETDEWEB)

    Leroux, Paul, E-mail: paul.leroux@kuleuven.be [KU Leuven, Dept. of Electrical Engineering (ESAT), AdvISe, Kleinhoefstraat 4, 2440 Geel (Belgium); Van Koeckhoven, Wesley; Verbeeck, Jens [KU Leuven, Dept. of Electrical Engineering (ESAT), AdvISe, Kleinhoefstraat 4, 2440 Geel (Belgium); Van Uffelen, Marco; Esqué, Salvador; Ranz, Roberto; Damiani, Carlo [Fusion for Energy, Torres Diagonal Litoral B3, Josep Pla 2, 08019 Barcelona (Spain); Hamilton, David [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul-lez-Durance (France)

    2014-10-15

    During future ITER maintenance operations, sensors and their embarked electronics will be exposed to a hostile and radioactive environment. This paper presents the design of a MGy radiation tolerant 16 bit resolver-to-digital converter (RDC) in 130 nm CMOS technology. The RDC features a Type II digital tracking loop, able to track resolvers with speeds up to 300 rps, and excitation frequencies up to 4 kHz. The RDC uses two integrated ΔΣ-analog-to-digital converters (ADCs) to digitize the resolver outputs. The 16 bit, 10 kHz ADCs utilize a correlated double sampling technique to remove radiation induced offset and 1/f-noise. The front-end features a static angular resolution of 16 bits (4.2 arcsec{sub rms}) and a resolution of 10 bits (6 arcmin{sub rms}) at a rotor speed of 100 rps. The circuit has a simulated radiation tolerance exceeding 1 MGy. It has the ability to operate under temperatures up to 125 °C, and to allow multiplexing with signals from other conventional sensors for compact, robust read-out architectures.

  15. Initial Efforts in Characterizing Radiation and Plasma Effects on Space Assets: Bridging the Space Environment, Engineering and User Community

    Science.gov (United States)

    Zheng, Y.; Ganushkina, N. Y.; Guild, T. B.; Jiggens, P.; Jun, I.; Mazur, J. E.; Meier, M. M.; Minow, J. I.; Pitchford, D. A.; O'Brien, T. P., III; Shprits, Y.; Tobiska, W. K.; Xapsos, M.; Rastaetter, L.; Jordanova, V. K.; Kellerman, A. C.; Fok, M. C. H.

    2017-12-01

    The Community Coordinated Modeling Center (CCMC) has been leading the community-wide model validation projects for many years. Such effort has been broadened and extended via the newly-launched International Forum for Space Weather Modeling Capabilities Assessment (https://ccmc.gsfc.nasa.gov/assessment/), Its objective is to track space weather models' progress and performance over time, which is critically needed in space weather operations. The Radiation and Plasma Effects Working Team is working on one of the many focused evaluation topics and deals with five different subtopics: Surface Charging from 10s eV to 40 keV electrons, Internal Charging due to energetic electrons from hundreds keV to several MeVs. Single Event Effects from solar energetic particles (SEPs) and galactic cosmic rays (GCRs) (several MeV to TeVs), Total Dose due to accumulation of doses from electrons (>100 KeV) and protons (> 1 MeV) in a broad energy range, and Radiation Effects from SEPs and GCRs at aviation altitudes. A unique aspect of the Radiation and Plasma Effects focus area is that it bridges the space environments, engineering and user community. This presentation will summarize the working team's progress in metrics discussion/definition and the CCMC web interface/tools to facilitate the validation efforts. As an example, tools in the areas of surface charging/internal charging will be demoed.

  16. Adaptation to high CO2 concentration in an optimal environment: radiation capture, canopy quantum yield and carbon use efficiency

    Science.gov (United States)

    Monje, O.; Bugbee, B.

    1998-01-01

    The effect of elevated [CO2] on wheat (Triticum aestivum L. Veery 10) productivity was examined by analysing radiation capture, canopy quantum yield, canopy carbon use efficiency, harvest index and daily C gain. Canopies were grown at either 330 or 1200 micromoles mol-1 [CO2] in controlled environments, where root and shoot C fluxes were monitored continuously from emergence to harvest. A rapidly circulating hydroponic solution supplied nutrients, water and root zone oxygen. At harvest, dry mass predicted from gas exchange data was 102.8 +/- 4.7% of the observed dry mass in six trials. Neither radiation capture efficiency nor carbon use efficiency were affected by elevated [CO2], but yield increased by 13% due to a sustained increase in canopy quantum yield. CO2 enrichment increased root mass, tiller number and seed mass. Harvest index and chlorophyll concentration were unchanged, but CO2 enrichment increased average life cycle net photosynthesis (13%, P < 0.05) and root respiration (24%, P < 0.05). These data indicate that plant communities adapt to CO2 enrichment through changes in C allocation. Elevated [CO2] increases sink strength in optimal environments, resulting in sustained increases in photosynthetic capacity, canopy quantum yield and daily C gain throughout the life cycle.

  17. A backward method to estimate the Dai-ichi reactor core damage using radiation exposure in the environment

    International Nuclear Information System (INIS)

    PM Udiyani; S Kuntjoro; S Widodo

    2016-01-01

    The Fukushima accident resulted in the melting of the reactor core due to loss of supply of coolant when the reactor stopped from operating conditions. The earthquake and tsunami caused loss of electricity due to the flooding that occurred in the reactor. The absence of the coolant supply after reactor shutdown resulted in heat accumulation, causing the temperature of the fuel to rise beyond its melting point. In the early stages of the accident, operator could not determine the severity of the accident and the percentage of the reactor core damaged. The available data was based on the radiation exposure in the environment that was reported by the authorities. The aim of this paper is to determine the severity of the conditions in the reactor core based on the radiation doses measured in the environment. The method is performed by backward counting based on the measuring radiation exposure and radionuclides releases source term. The calculation was performed by using the PC-COSYMA code. The results showed that the core damage fraction at Dai-ichi Unit 1 was 70%, and the resulting individual effective dose in the exclusion area is 401 mSv, while the core damage fraction at Unit 2 was 30%, and the resulting individual effective dose was 9.1 mSv, while for Unit 3, the core damage fraction was 25% for an individual effective dose of 92.2 mSv. The differences between the results of the calculation for estimation of core damage proposed in this paper with the previously reported results is probably caused by the applied model for assessment, differences in postulations and assumptions, and the incompleteness of the input data. This difference could be reduced by performing calculations and simulations for more varied assumptions and postulations. (author)

  18. Radiation Protection of the Public and the Environment. Overcoming Environmental Monitoring Inertia

    International Nuclear Information System (INIS)

    Parker, T.G.; Desmond, J.A.; Stevens, A.K.

    2006-01-01

    The first nuclear reactors at Sellafield went critical in 1951 and fuel reprocessing commenced shortly afterwards. As the nuclear programme expanded, reprocessing increased and there was an associated increase in discharges to the environment. An initial environmental monitoring programme was formulated on the basis of research and assessment of the likely behaviour of radionuclides. In addition to the routine process sources there were also incidents that gave rise to acute releases of radioactivity to the environment. Of key significance were: the Windscale fire, 1957; short-cooled fuel reprocessing, 1981; and discharge of contaminated solvent, 1983. All of these incidents added to the requirements for environments for environmental monitoring. The monitoring programme has evolved over a period of more than 50 years. (N.C.)

  19. The close environments of accreting massive black holes are shaped by radiative feedback.

    Science.gov (United States)

    Ricci, Claudio; Trakhtenbrot, Benny; Koss, Michael J; Ueda, Yoshihiro; Schawinski, Kevin; Oh, Kyuseok; Lamperti, Isabella; Mushotzky, Richard; Treister, Ezequiel; Ho, Luis C; Weigel, Anna; Bauer, Franz E; Paltani, Stephane; Fabian, Andrew C; Xie, Yanxia; Gehrels, Neil

    2017-09-27

    The majority of the accreting supermassive black holes in the Universe are obscured by large columns of gas and dust. The location and evolution of this obscuring material have been the subject of intense research in the past decades, and are still debated. A decrease in the covering factor of the circumnuclear material with increasing accretion rates has been found by studies across the electromagnetic spectrum. The origin of this trend may be driven by the increase in the inner radius of the obscuring material with incident luminosity, which arises from the sublimation of dust; by the gravitational potential of the black hole; by radiative feedback; or by the interplay between outflows and inflows. However, the lack of a large, unbiased and complete sample of accreting black holes, with reliable information on gas column density, luminosity and mass, has left the main physical mechanism that regulates obscuration unclear. Here we report a systematic multi-wavelength survey of hard-X-ray-selected black holes that reveals that radiative feedback on dusty gas is the main physical mechanism that regulates the distribution of the circumnuclear material. Our results imply that the bulk of the obscuring dust and gas is located within a few to tens of parsecs of the accreting supermassive black hole (within the sphere of influence of the black hole), and that it can be swept away even at low radiative output rates. The main physical driver of the differences between obscured and unobscured accreting black holes is therefore their mass-normalized accretion rate.

  20. Monitoring of radiation in the environment in the Netherlands. Results in 2000

    CERN Document Server

    Knetsch, G J

    2002-01-01

    This report presents the results of radioactivity measurements in the environment in the Netherlands carried out by RIVM, RIZA, RIKZ and Inspectorate for Health Protection and Veterinary Public Health in 2000. Measurements of radioactivity have been carried out in airborne particulates, deposition, surface water, seawater, drinking water and food (honey, game, blueberry and mushrooms). Results for ambient dose equivalent rates have been obtained from the National Radioactivity Monitoring Network. No measurements were done in milk. In 2000 no elevated levels of radioactivity were found in the Dutch environment

  1. Monitoring of radiation in the environment in the Netherlands. Results in 2000

    Energy Technology Data Exchange (ETDEWEB)

    Knetsch, G.J. (ed.)

    2002-07-01

    This report presents the results of radioactivity measurements in the environment in the Netherlands carried out by RIVM, RIZA, RIKZ and Inspectorate for Health Protection and Veterinary Public Health in 2000. Measurements of radioactivity have been carried out in airborne particulates, deposition, surface water, seawater, drinking water and food (honey, game, blueberry and mushrooms). Results for ambient dose equivalent rates have been obtained from the National Radioactivity Monitoring Network. No measurements were done in milk. In 2000 no elevated levels of radioactivity were found in the Dutch environment.

  2. Leishmania infantum infection in two captive barbary lions (Panthera leo leo).

    Science.gov (United States)

    Libert, Cédric; Ravel, Christophe; Pratlong, Francine; Lami, Patrick; Dereure, Jacques; Keck, Nicolas

    2012-09-01

    A female barbary lion (Panthera leo leo) from the Montpellier Zoological Park (France) showing colitis, epistaxis, and lameness with pad ulcers was positive by polymerase chain reaction (PCR) for Leishmania infantum. Further indirect immunofluorescence (IFAT) tests on the banked sera from all lions of the park detected another infected but asymptomatic female, which was confirmed by PCR on ethylenediaminetetraacetic acid (EDTA) blood sample. Leishmania infantum zymodeme MON-1 was cultured from EDTA bone marrow samples sampled from this second animal. The first female was successfully treated with marbofloxacine at 2 mg/kg s.i.d. for 28 days (Marbocyl, Vetoquinol 70204 Lure, France) and allopurinol at 30 mg/kg s.i.d. for 3 mo (Allopurinol Mylan, Mylan SAS, 69800 Saint-Priest, France) and then 1 wk/mo. Both positive animals were born at the Rabat Zoological Park, Morocco, and arrived together at Montpellier in 2003. The chronicity and source of this current infection are unknown since Morocco and southern France are well-known to be enzootic for leishmaniasis.

  3. Radiation protection research projects. Program report 2015. Report on research program radiation protection of the Federal ministry for environment, nature conservation and reactor safety with technical and administrative steering by the Bundesamt fuer Strahlenschutz

    International Nuclear Information System (INIS)

    Schmitt-Hannig, Annemarie; Loebke-Reinl, Angelika; Peter, Josef; Goedde, Ralph; Hachenberger, Claudia; Trugenberger-Schnabel, Angela

    2016-08-01

    On behalf of the Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB) the Federal Office for Radiation Protection (BfS) awards research grants for projects in the field of radiation protection. The findings of these projects serve as decision aiding information in the development of radiation protection regulations as well as in the fulfilment of specific tasks in the field of radiation protection. The tasks of the Federal Office for Radiation Protection involve planning, technical and administrative preparation, awarding of contracts, general support as well as the technical evaluation of research and study projects. This report provides information on results, i. e. preliminary (in the form of status reports) and, where applicable, final results of radiation protection projects within the BMUB's Environmental Research Plan for the year 2015.

  4. Potential for radiation processing as a technique for the conservation of the environment in Ghana

    International Nuclear Information System (INIS)

    Gbedemah, C.M.

    1998-01-01

    Environmental pollution in developing countries such as Ghana transcend many fields of human activity. Rivers that serve urban communities as sources of potable water encounter challenges of pollution as a result of agricultural, industrial and domestic activity. The wood processing industry leaves in its trail huge amounts of sawdust. Urban sewage also creates environmental problems if not managed adequately. Contaminated imported foods become sources for the introduction of new microflora into developing countries. Such new microflora can result in health problems in such societies. This paper discusses the enormity of these problems in Ghana with a proposal for minimising them by the application of radiation processing technology

  5. Radiation education using local environment. Educational experiment using Misasa spring water

    International Nuclear Information System (INIS)

    Nakamura, Mariko; Esaka, Takao; Kamata, Masahiro

    2005-01-01

    Hoping that use of natural radioactivity as teaching materials helps learners to understand the existence of radiation in nature, the authors developed several kinds of safe and inexpensive experiments for elementary and junior high school education using hot spring water taken from Misasa, situated in Tottori prefecture, Japan. Here, they report the details of experimental procedure to observe the radioactive equilibrium between Rn 222 released from the hot spring water and its daughters as well as the decay after isolation from Rn 222. The experiment needs no hazardous chemicals nor Bunsen burners, and can be carried out in normal classrooms without any special apparatus. (S. Ohno)

  6. A nonventing cooling system for space environment extravehicular activity, using radiation and regenerable thermal storage

    Science.gov (United States)

    Bayes, Stephen A.; Trevino, Luis A.; Dinsmore, Craig E.

    1988-01-01

    This paper outlines the selection, design, and testing of a prototype nonventing regenerable astronaut cooling system for extravehicular activity space suit applications, for mission durations of four hours or greater. The selected system consists of the following key elements: a radiator assembly which serves as the exterior shell of the portable life support subsystem backpack; a layer of phase change thermal storage material, n-hexadecane paraffin, which acts as a regenerable thermal capacitor; a thermoelectric heat pump; and an automatic temperature control system. The capability for regeneration of thermal storage capacity with and without the aid of electric power is provided.

  7. Impact of radioactivity on problematic environment, knowledge situation, and approaches toward radiation protection criteria identification

    International Nuclear Information System (INIS)

    Brechignac, F.

    2001-01-01

    The scraps of knowledge existing todays about the environmental radiation protection are based on the dose limits (10 and 1 mGy.h -1 ) that have been determined from literature relative to effects of acute exposure by external irradiation on individuals. But these standards come from a context far from environmental reality. Some research directions are coming out: to complete the radioecological knowledge of transfers, the biological accumulation in living organisms, to study the effects of this bioaccumulation in a multi pollution context with chronic low dose exposure; to identify the characteristics of these effects( low doses in chronic multi pollutions) at the ecosystem level. (N.C.)

  8. Development of flexible LEO-resistant PI films for space applications using a self-healing mechanism by surface-directed phase separation of block copolymers

    NARCIS (Netherlands)

    Fischer, H.R.; Tempelaars, K.; Kerpershoek, A.M.; Dingemans, T.; Iqbal, M.; Lonkhuyzen, H.; Iwanowsky, B.; Semprimoschnig, C.

    2010-01-01

    Polimide-block-polydimethylsiloxane (PI-b-PDMS) block copolymers have been synthesized from commercially available amino-terminated polysiloxanes with different molecular weights, for use as polymeric materials resistant to the low earth orbit (LEO) space environment. A structural optimization with

  9. Monitoring of radiation in the environment in the Netherlands. Results in 2000

    NARCIS (Netherlands)

    Knetsch GJ; LSO; RIZA; RIKZ; Keuringsdienst van Waren

    2002-01-01

    This report presents the results of radioactivity measurements in the environment in the Netherlands carried out by RIVM, RIZA, RIKZ and Inspectorate for Health Protection and Veterinary Public Health in 2000. Measurements of radioactivity have been carried out in airborne particulates, deposition,

  10. Monitoring of radiation in the environment in the Netherlands. Results in 2001

    NARCIS (Netherlands)

    Knetsch GJ; RIZA; RIKZ; LSO

    2003-01-01

    This report presents the results of radioactivity measurements in the Dutch environment in 2001. The measurements were carried out by RIVM, RIZA, RIKZ and Inspectorate for Health Protection and Veterinary Public Health. Radioactivity measurements were carried out on airborne particles, deposition,

  11. Effects of radiation on the chemical environment surrounding waste canisters in proposed repository sites and possible effects on the corrosion process

    International Nuclear Information System (INIS)

    Glass, R.S.

    1981-12-01

    This report explores the interaction of ionizing radiation with various environments. In particular, worst case (aqueous) environments for the proposed nuclear waste repository sites are considered. Emphasis is on the fundamental chemical and physical processes involved. The identities of possible radiolysis products (both transient and stable) have been sought through a literature search. The effect of radiation on corrosion processes is discussed. The radiation-induced chemical environment in the worst case repository sites is not well defined. Attention should therefore be given to fundamental studies exploring the interaction of such environments with components of the nuclear waste package, including the canister materials and backfills. Identification and quantification of radiolysis products would be helpful in this regard

  12. Malignant lymphoma in african lions (panthera leo).

    Science.gov (United States)

    Harrison, T M; McKnight, C A; Sikarskie, J G; Kitchell, B E; Garner, M M; Raymond, J T; Fitzgerald, S D; Valli, V E; Agnew, D; Kiupel, M

    2010-09-01

    Malignant lymphoma has become an increasingly recognized problem in African lions (Panthera leo). Eleven African lions (9 male and 2 female) with clinical signs and gross and microscopic lesions of malignant lymphoma were evaluated in this study. All animals were older adults, ranging in age from 14 to 19 years. Immunohistochemically, 10 of the 11 lions had T-cell lymphomas (CD3(+), CD79a(-)), and 1 lion was diagnosed with a B-cell lymphoma (CD3(-), CD79a(+)). The spleen appeared to be the primary site of neoplastic growth in all T-cell lymphomas, with involvement of the liver (6/11) and regional lymph nodes (5/11) also commonly observed. The B-cell lymphoma affected the peripheral lymph nodes, liver, and spleen. According to the current veterinary and human World Health Organization classification of hematopoietic neoplasms, T-cell lymphoma subtypes included peripheral T-cell lymphoma (4/11), precursor (acute) T-cell lymphoblastic lymphoma/leukemia (2/11), chronic T-cell lymphocytic lymphoma/leukemia (3/11), and T-zone lymphoma (1/11). The single B-cell lymphoma subtype was consistent with diffuse large B-cell lymphoma. Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) testing by immunohistochemistry on sections of malignant lymphoma was negative for all 11 lions. One lion was seropositive for FeLV. In contrast to domestic and exotic cats, in which B-cell lymphomas are more common than T-cell lymphomas, African lions in this study had malignant lymphomas that were primarily of T-cell origin. Neither FeLV nor FIV, important causes of malignant lymphoma in domestic cats, seems to be significant in the pathogenesis of malignant lymphoma in African lions.

  13. Radioecology of and radiation dose from Dutch waste gypsum released into the environment

    International Nuclear Information System (INIS)

    Koster, H.W.; Weers, A.W. van; Netherlands Energy Research Foundation, Petten)

    1985-11-01

    The Dutch industries release 9 kinds of waste gypsum, 90% of the total quantity is phosphogypsum. Only waste gypsums from the phosphate industries show increased radioactivity, the strongest in phosphogypsum. All phosphogypsum, 2 Tg.a -1 , is disposed of into the Rhine at Rotterdam. This leads to an increase of radionuclides, from the U-238 chain, along the Dutch coast. The calculated increase of activity concentrations in sea food causes an increase of the individual radiation dose of maximal 150 μSv.a -1 and of the Dutch population dose of 170 manSv.a -1 . Stacking of the phosphogypsum would result in a dose increase of one order of magnitude lower. The need for environmental disposal or stacking of at least the fine and coarse fractions of the phosphogypsum, which are difficult to recycle, will remain. (Auth.)

  14. Radiation technology in finishing process improves health, safety and environment (HSE) in the furniture manufacturing industry

    International Nuclear Information System (INIS)

    Ahmad Shakri Mat Seman

    1999-01-01

    In furniture manufacturing, processes like cross cutting, molding, planning, shaping, turning, assembling and finishing are involved. The most significant types of negative impact of these processes are such as dust emission, noise, hazardous work, health risk, emission of organic solvent, toxic chemicals emission and chemical waste. In the finishing process, a number of negative effects that will cause health, safety and environmental (HSE) performance. This article highlights the environmental problems in the furniture finishing processes and how the radiation technology can reduce these negative impacts. The drawbacks that hamper the manufacturers from adopting this technology are also discussed. The objective of the paper is to create the awareness among the industrialist and consumers on the HSE hazardous in furniture finishing and steps can be taken to improve

  15. Ozone depletion and solar ultraviolet radiation: ocular effects, a United nations environment programme perspective.

    Science.gov (United States)

    Cullen, Anthony P

    2011-07-01

    To describe he role played by the United Nations Environmental Effects Panel with respect to the ocular effects of stratospheric ozone depletion and present the essence of the Health Chapter of the 2010 Assessment. A consideration of solar ultraviolet radiation (UVR) at the Earth's surface as it is affected by atmospheric changes and how these influence sunlight-related eye diseases. A review of the current Assessment with emphasis on pterygium, cataract, ocular melanoma, and age-related macular degeneration. Although the ozone layer is projected to recover slowly in the coming decades, continuing vigilance is required regarding exposure to the sun. Evidence implicating solar UVR, especially UVB, in every tissue of the eye continues to be amassed. The need for ocular UV protection existed before the discovery of the depletion of the ozone layer and will continue even when the layer fully recovers in approximately 2100.

  16. Radiation effect on silicon transistors in mixed neutrons-gamma environment

    Science.gov (United States)

    Assaf, J.; Shweikani, R.; Ghazi, N.

    2014-10-01

    The effects of gamma and neutron irradiations on two different types of transistors, Junction Field Effect Transistor (JFET) and Bipolar Junction Transistor (BJT), were investigated. Irradiation was performed using a Syrian research reactor (RR) (Miniature Neutron Source Reactor (MNSR)) and a gamma source (Co-60 cell). For RR irradiation, MCNP code was used to calculate the absorbed dose received by the transistors. The experimental results showed an overall decrease in the gain factors of the transistors after irradiation, and the JFETs were more resistant to the effects of radiation than BJTs. The effect of RR irradiation was also greater than that of gamma source for the same dose, which could be because neutrons could cause more damage than gamma irradiation.

  17. Radiation dose resulting from the releases of fly ash in the environment

    International Nuclear Information System (INIS)

    Koester, H.W.; Leenhouts, H.P.; Frissel, M.J.

    1986-06-01

    The radiological consequences from radioactivity in the emissions of coal fired power stations are evaluated for the Dutch population until the year 2030. The energy scenario for the Netherlands with the highest coal input considers an input of 55 Tg coal per year in 2030. The fly ash production is then 5.3 Tg, while 0.03 Tg fly ash will be released into the atmosphere. The radiation doses which result from the radionuclides present in the fly ash were calculated. Several pathways were considered, contribution of most of them were insignificant. However, the inhalation of fly ash may cause and H eff of 4.0 E-7 Sv.a -1 . The contribution caused by the ingestion of milk contaminated via depositions of fly ash on grass and soil may reach 0.8 E-7 Sv.a -1 . The report contains numerous calculations, references and a parameter analysis. (Auth.)

  18. Radiation-hardened nano-particles-based Erbium-doped fiber for space environment

    Science.gov (United States)

    Thomas, Jérémie; Myara, Mikhaël.; Signoret, Philippe; Burov, Ekaterina; Pastouret, Alain; Melin, Gilles; Boivin, David; Gilard, Olivier; Sotom, Michel

    2017-11-01

    We demonstrate for the first time a radiationresistant Erbium-Doped Fiber exhibiting performances that can fill the requirements of Erbium-Doped Fiber Amplifiers for space applications. This is based on an Aluminum co-doping atom reduction enabled by Nanoparticules Doping-Process. For this purpose, we developed several fibers containing very different erbium and aluminum concentrations, and tested them in the same optical amplifier configuration. This work allows to bring to the fore a highly radiation resistant Erbium-doped pure silica optical fiber exhibiting a low quenching level. This result is an important step as the EDFA is increasingly recognized as an enabling technology for the extensive use of photonic sub-systems in future satellites.

  19. Evaluation of the neutron radiation environment inside the International Space Station based on the Bonner Ball Neutron Detector experiment

    International Nuclear Information System (INIS)

    Koshiishi, H.; Matsumoto, H.; Chishiki, A.; Goka, T.; Omodaka, T.

    2007-01-01

    The Bonner Ball Neutron Detector (BBND) experiment was conducted onboard the US Laboratory Module of the International Space Station (ISS) as part of the Human Research Facility project of NASA in order to evaluate the neutron radiation environment in the energy range from thermal up to 15 MeV inside the ISS. The BBND experiment was carried out over an eight-month period from 23 March through 14 November 2001, corresponding to the maximum period of solar-activity variation. The neutron differential-energy spectra are compared with the model neutron spectrum predicted for the inside of the ISS, and are found to be in good agreement for E>10keV. In contrast, the ISS model spectrum has lower flux for E<10keV, which is likely due to the difference in the shielding environment. The neutron dose equivalent rates are 69 and 88μSv/day for the two locations inside the US Laboratory Module, representing a 30% increase due to the difference in the localized shielding environment inside the same pressurized module. The influence of the ISS altitude variation is estimated for the neutron dose equivalent rate to increase by a factor of 2 over the ISS altitude variation of 300-500 km. The increase in the cumulative neutron dose equivalent due to the most significant solar event during the BBND experiment is 0.15 mSv, which contributes less than 1% to the annual neutron dose equivalent estimated from the BBND experiment

  20. Space Radiation: The Number One Risk to Astronaut Health beyond Low Earth Orbit

    Directory of Open Access Journals (Sweden)

    Jeffery C. Chancellor

    2014-09-01

    Full Text Available Projecting a vision for space radiobiological research necessitates understanding the nature of the space radiation environment and how radiation risks influence mission planning, timelines and operational decisions. Exposure to space radiation increases the risks of astronauts developing cancer, experiencing central nervous system (CNS decrements, exhibiting degenerative tissue effects or developing acute radiation syndrome. One or more of these deleterious health effects could develop during future multi-year space exploration missions beyond low Earth orbit (LEO. Shielding is an effective countermeasure against solar particle events (SPEs, but is ineffective in protecting crew members from the biological impacts of fast moving, highly-charged galactic cosmic radiation (GCR nuclei. Astronauts traveling on a protracted voyage to Mars may be exposed to SPE radiation events, overlaid on a more predictable flux of GCR. Therefore, ground-based research studies employing model organisms seeking to accurately mimic the biological effects of the space radiation environment must concatenate exposures to both proton and heavy ion sources. New techniques in genomics, proteomics, metabolomics and other “omics” areas should also be intelligently employed and correlated with phenotypic observations. This approach will more precisely elucidate the effects of space radiation on human physiology and aid in developing personalized radiological countermeasures for astronauts.

  1. Space Radiation: The Number One Risk to Astronaut Health beyond Low Earth Orbit

    Science.gov (United States)

    Chancellor, Jeffery C.; Scott, Graham B. I.; Sutton, Jeffrey P.

    2014-01-01

    Projecting a vision for space radiobiological research necessitates understanding the nature of the space radiation environment and how radiation risks influence mission planning, timelines and operational decisions. Exposure to space radiation increases the risks of astronauts developing cancer, experiencing central nervous system (CNS) decrements, exhibiting degenerative tissue effects or developing acute radiation syndrome. One or more of these deleterious health effects could develop during future multi-year space exploration missions beyond low Earth orbit (LEO). Shielding is an effective countermeasure against solar particle events (SPEs), but is ineffective in protecting crew members from the biological impacts of fast moving, highly-charged galactic cosmic radiation (GCR) nuclei. Astronauts traveling on a protracted voyage to Mars may be exposed to SPE radiation events, overlaid on a more predictable flux of GCR. Therefore, ground-based research studies employing model organisms seeking to accurately mimic the biological effects of the space radiation environment must concatenate exposures to both proton and heavy ion sources. New techniques in genomics, proteomics, metabolomics and other “omics” areas should also be intelligently employed and correlated with phenotypic observations. This approach will more precisely elucidate the effects of space radiation on human physiology and aid in developing personalized radiological countermeasures for astronauts. PMID:25370382

  2. Hazards of ionizing radiations for human beings and environment with respect to nuclear facilities; Gefahren ionisierender Strahlung fuer Mensch und Umwelt in Bezug auf kerntechnische Anlagen

    Energy Technology Data Exchange (ETDEWEB)

    Huebner, Felix; Jung, Jennifer Jana; Schultmann, Frank

    2017-03-15

    Worldwide, nuclear fission is used to produce electricity. On the one hand, the low emission of CO{sub 2} is often mentioned as an advantage of this technology. On the other hand, warnings about the dangers of nuclear fission are mentioned. Consequently, an overview about the dangers of ionizing radiation to human beings as well as animals and the environment is important. However, the focus will be on possible health effects for humans with regards to nuclear power plants. In nuclear power plants, both natural types of radiation and artificially produced radiation occur. During normal operation, it is possible that small quantities of this ionizing radiation are released to the environment. In case of nuclear disasters or faults during decommissioning and dismantling processes the consequences of thereby emitted quantities can be even more severe. Reference nuclides vary by reactor type, operating stage and respective incident. At the beginning, different types of radiation and their characteristics and effects on the affected organism are explained. Sensitive organs are emphasized in this context. The individual risk is determined by numerous factors and therefore cannot be predicted. Based on scientific studies and medical publications the hazards of ionizing radiation are compiled. Effects of high exposure of ionizing radiation are well-investigated. Scientists are still divided over the connection between several diseases and the exposure to low doses of ionizing radiation. For this reason, the positions of different international organizations are critically contrasted in this study.

  3. Temperature and soil water status effects on radiation use and growth of pearl millet in a semi-arid environment

    International Nuclear Information System (INIS)

    McIntyre, B.D.; Flower, D.J.; Riha, S.J.

    1993-01-01

    In semi-arid environments, crops are frequently subjected to a combination of high air temperatures, large atmospheric saturation vapor pressure deficits, high soil temperatures and reduced soil water status. To explore the performance of pearl millet (Pennisetum typhoides S. and H., cv. CIVT) from panicle initiation to flowering (GS 2) when grown in the field under combinations of these conditions, experiments were conducted in northern Nigeria in three seasons in which daily mean air temperatures during 18 days of this stage averaged 22, 27 and 33°C, and saturation vapor pressure deficits averaged 3.7, 4.0 and 5.2 kPa, respectively. In each experiment, half of the crop was irrigated, while the other half received no water after panicle initiation. For irrigated millet, radiation use efficiency (RUE) did not vary significantly (P = 0.05) for the three experiments (1.7 g MJ−1). RUE of non-irrigated millet was significantly reduced (0.8 g MJ−1) only during the season with the highest temperature. Radiation interception as a function of thermal time was similar in the irrigated and non-irrigated treatments except in the season with the highest temperatures, when radiation interception was reduced about 25% in the non-irrigated relative to the irrigated treatment. Stem extension of non-irrigated millet did not decline relative to irrigated millet, despite the almost complete extraction of plant available water in the upper 30 cm of the soil, except during the season with the highest temperatures, when stem extension rates began to decline as soon as water was withheld. Under high air temperatures and saturation vapor pressure deficits, dry matter accumulation in both irrigated and non-irrigated millet during GS 2 could be reasonably predicted from RUE and radiation interception. However, when high soil temperatures (daily mean at 5 cm of 34°C) occurred in the non-irrigated treatment, both RUE and radiation interception decreased relative to all other treatments

  4. Investigation of individual radiation exposures from discharges to the aquatic environment: techniques used in habits surveys

    International Nuclear Information System (INIS)

    Leonard, D.R.P.; Hunt, G.J.; Jones, P.G.W.

    1982-01-01

    The techniques used by the Fisheries Radiobiological Laboratory (FRL) in conducting habits surveys are described and discussed. The main objectives of these surveys are to investigate exposure pathways to the public resulting from radioactive discharges to the aquatic environment and to provide the basic data from which critical groups can be identified. Preparation, conduct and interpretation of the results of surveys are described and possible errors obtained by the interview technique are highlighted. A means of verifying the results of interviews by a logging technique has been devised and some comparative results are presented. (author)

  5. Robotics in nuclear engineering: Computer assisted teleoperation in hazardous environments with particular reference to radiation fields

    International Nuclear Information System (INIS)

    Larcombe, M.H.E.

    1984-01-01

    A report which examines the potential of robot devices in hazardous environments in nuclear engineering, such as: Fuel processing; Reactor maintenance; Reactor decommissioning; Transportation of active material; Waste handling; Incident management. The book reviews the present state of the art in remote controlled robots, and gives total system predictions for possible future applications within the nuclear industry. It examines the planning aspects of a programme of development for the technology, and highlights the priorities. Detailed descriptions are provided of the hardware and techniques which already contribute, or should contribute in the future, to the development of useable remote controlled robotics systems

  6. An evaluation of radiation exposures in a tropical phosphogypsum disposal environment.

    Science.gov (United States)

    Haridasan, P P; Pillai, P M B; Tripathi, R M; Puranik, V D

    2009-07-01

    Environmental radiological aspects of phosphatic fertiliser production with particular reference to disposal of phosphogypsum at two sites in India are examined. Concentration of uranium and its decay products in the rock phosphate and products are presented. External gamma exposure and inhalation of radon and progeny are found to be the major routes of exposure to public in phosphogypsum disposal environment. An estimate of the committed effective dose to a representative person gives an average additional dose of 0.6 mSv annually in the study sites.

  7. SU-F-T-249: Application of Human Factors Methods: Usability Testing in the Radiation Oncology Environment

    Energy Technology Data Exchange (ETDEWEB)

    Warkentin, H [Cross Cancer Institute, Edmonton, AB (Canada); Bubric, K [Alberta Health Services, Calgary, AB (Canada); Giovannetti, H [Jack Ady Cancer Centre, Lethbridge, AB (Canada); Graham, G [Tom Baker Cancer Centre, Calgary, AB (Canada); Clay, C [Central Alberta Cancer Centre, Red Deer, AB (Canada)

    2016-06-15

    Purpose: As a quality improvement measure, we undertook this work to incorporate usability testing into the implementation procedures for new electronic documents and forms used by four affiliated radiation therapy centers. Methods: A human factors specialist provided training in usability testing for a team of medical physicists, radiation therapists, and radiation oncologists from four radiotherapy centers. A usability testing plan was then developed that included controlled scenarios and standardized forms for qualitative and quantitative feedback from participants, including patients. Usability tests were performed by end users using the same hardware and viewing conditions that are found in the clinical environment. A pilot test of a form used during radiotherapy CT simulation was performed in a single department; feedback informed adaptive improvements to the electronic form, hardware requirements, resource accessibility and the usability testing plan. Following refinements to the testing plan, usability testing was performed at three affiliated cancer centers with different vault layouts and hardware. Results: Feedback from the testing resulted in the detection of 6 critical errors (omissions and inability to complete task without assistance), 6 non-critical errors (recoverable), and multiple suggestions for improvement. Usability problems with room layout were detected at one center and problems with hardware were detected at one center. Upon amalgamation and summary of the results, three key recommendations were presented to the document’s authors for incorporation into the electronic form. Documented inefficiencies and patient safety concerns related to the room layout and hardware were presented to administration along with a request for funding to purchase upgraded hardware and accessories to allow a more efficient workflow within the simulator vault. Conclusion: By including usability testing as part of the process when introducing any new document

  8. SU-F-T-249: Application of Human Factors Methods: Usability Testing in the Radiation Oncology Environment

    International Nuclear Information System (INIS)

    Warkentin, H; Bubric, K; Giovannetti, H; Graham, G; Clay, C

    2016-01-01

    Purpose: As a quality improvement measure, we undertook this work to incorporate usability testing into the implementation procedures for new electronic documents and forms used by four affiliated radiation therapy centers. Methods: A human factors specialist provided training in usability testing for a team of medical physicists, radiation therapists, and radiation oncologists from four radiotherapy centers. A usability testing plan was then developed that included controlled scenarios and standardized forms for qualitative and quantitative feedback from participants, including patients. Usability tests were performed by end users using the same hardware and viewing conditions that are found in the clinical environment. A pilot test of a form used during radiotherapy CT simulation was performed in a single department; feedback informed adaptive improvements to the electronic form, hardware requirements, resource accessibility and the usability testing plan. Following refinements to the testing plan, usability testing was performed at three affiliated cancer centers with different vault layouts and hardware. Results: Feedback from the testing resulted in the detection of 6 critical errors (omissions and inability to complete task without assistance), 6 non-critical errors (recoverable), and multiple suggestions for improvement. Usability problems with room layout were detected at one center and problems with hardware were detected at one center. Upon amalgamation and summary of the results, three key recommendations were presented to the document’s authors for incorporation into the electronic form. Documented inefficiencies and patient safety concerns related to the room layout and hardware were presented to administration along with a request for funding to purchase upgraded hardware and accessories to allow a more efficient workflow within the simulator vault. Conclusion: By including usability testing as part of the process when introducing any new document

  9. Estimation of radiation exposure associated with inert gas radionuclides discharged to the environment by the nuclear power industry

    International Nuclear Information System (INIS)

    Bryant, P.M.; Jones, J.A.

    1973-05-01

    Several fission product isotopes of krypton and xenon are formed during operation of nuclear power stations, while other radioactive inert gases, notably isotopes of argon and nitrogen, are produced as neutron activation products. With the exception of 85 Kr these radionuclides are short-lived, and the containment and hold-up arrangements in different reactor systems influence the composition of the inert gas mixtures discharged to the environment. Cooling of irradiated fuel before chemical reprocessing reduces very substantially the amounts of the short-lived krypton and xenon isotopes available for discharge at reprocessing plants, but almost all the 85 Kr formed in the fuel is currently discharged to atmosphere from these plants. Estimates are made of the radiation exposure of the public associated with these discharges to atmosphere taking into account the type of radiation emitted, radioactive half-life and the local, regional and world-wide populations concerned. Such estimates are often based on simple models in which activity is assumed to be distributed in a semi-infinite cloud. The model used in this assessment takes into account the finite cloud near the point of its discharge and its behaviour when dispersion in the atmosphere is affected by the presence of buildings. This is particularly important in the case of discharges from those reactors which do not have high stacks. The model also provides in detail for the continued world-wide circulation of the longer-lived 85 Kr. (author)

  10. Convergent evolution of SWS2 opsin facilitates adaptive radiation of threespine stickleback into different light environments.

    Directory of Open Access Journals (Sweden)

    David A Marques

    2017-04-01

    Full Text Available Repeated adaptation to a new environment often leads to convergent phenotypic changes whose underlying genetic mechanisms are rarely known. Here, we study adaptation of color vision in threespine stickleback during the repeated postglacial colonization of clearwater and blackwater lakes in the Haida Gwaii archipelago. We use whole genomes from 16 clearwater and 12 blackwater populations, and a selection experiment, in which stickleback were transplanted from a blackwater lake into an uninhabited clearwater pond and resampled after 19 y to test for selection on cone opsin genes. Patterns of haplotype homozygosity, genetic diversity, site frequency spectra, and allele-frequency change support a selective sweep centered on the adjacent blue- and red-light sensitive opsins SWS2 and LWS. The haplotype under selection carries seven amino acid changes in SWS2, including two changes known to cause a red-shift in light absorption, and is favored in blackwater lakes but disfavored in the clearwater habitat of the transplant population. Remarkably, the same red-shifting amino acid changes occurred after the duplication of SWS2 198 million years ago, in the ancestor of most spiny-rayed fish. Two distantly related fish species, bluefin killifish and black bream, express these old paralogs divergently in black- and clearwater habitats, while sticklebacks lost one paralog. Our study thus shows that convergent adaptation to the same environment can involve the same genetic changes on very different evolutionary time scales by reevolving lost mutations and reusing them repeatedly from standing genetic variation.

  11. Specification and Prediction of the Radiation Environment Using Data Assimilative VERB code

    Science.gov (United States)

    Shprits, Yuri; Kellerman, Adam

    2016-07-01

    We discuss how data assimilation can be used for the reconstruction of long-term evolution, bench-marking of the physics based codes and used to improve the now-casting and focusing of the radiation belts and ring current. We also discuss advanced data assimilation methods such as parameter estimation and smoothing. We present a number of data assimilation applications using the VERB 3D code. The 3D data assimilative VERB allows us to blend together data from GOES, RBSP A and RBSP B. 1) Model with data assimilation allows us to propagate data to different pitch angles, energies, and L-shells and blends them together with the physics-based VERB code in an optimal way. We illustrate how to use this capability for the analysis of the previous events and for obtaining a global and statistical view of the system. 2) The model predictions strongly depend on initial conditions that are set up for the model. Therefore, the model is as good as the initial conditions that it uses. To produce the best possible initial conditions, data from different sources (GOES, RBSP A, B, our empirical model predictions based on ACE) are all blended together in an optimal way by means of data assimilation, as described above. The resulting initial conditions do not have gaps. This allows us to make more accurate predictions. Real-time prediction framework operating on our website, based on GOES, RBSP A, B and ACE data, and 3D VERB, is presented and discussed.

  12. Aging of black carbon particles under polluted urban environments: timescale, hygroscopicity and enhanced absorption and direct radiative forcing

    Science.gov (United States)

    Peng, J.; Hu, M.; Guo, S.; Du, Z.; Zheng, J.; Shang, D.; Levy Zamora, M.; Shao, M.; Wu, Y.; Zheng, J.; Wang, Y.; Zeng, L.; Collins, D. R.; Molina, M.; Zhang, R.

    2017-12-01

    Black carbon (BC) exerts profound impacts on air quality and climate because of its high absorption cross-section over a broad range of electromagnetic spectra, but the current results on absorption enhancement of BC particles during atmospheric aging remain conflicting. Here, we quantified the aging and variation in the hygroscopic and optical properties of BC particles under ambient conditions in Beijing, China, and Houston, United States, using an outdoor environmental chamber approach. BC aging exhibits two distinct stages, i.e., initial transformation from a fractal to spherical morphology with little absorption variation and subsequent growth of fully compact particles with a large absorption enhancement. The timescales to achieve complete morphology modification and an absorption amplification factor of 2.4 for BC particles are estimated to be 2.3 h and 4.6 h, respectively, in Beijing, compared with 9 h and 18 h, respectively, in Houston. The κ (kappa) values of coating materials are calculated as 0.04 at both subsaturation and supersaturation conditions, respectively, indicating that the initial photochemical aging of BC particles does not appreciably alter the BC hygroscopicity. Our findings suggest that BC aging under polluted urban environments could play an essential role in pollution development and contribute importantly to large positive radiative forcing. The variation in direct radiative forcing is dependent on the rate and timescale of BC aging, with a clear distinction between urban cities in developed and developing countries, i.e., a higher climatic impact in more polluted environments. We suggest that mediation in BC emissions achieves a cobenefit in simultaneously controlling air pollution and protecting climate, especially for developing countries.

  13. Passivation Strategies on Board Airbus ds Leo Pcdus

    Directory of Open Access Journals (Sweden)

    Lapeña Emilio

    2017-01-01

    This paper deals with the different strategies followed in the Airbus DS LEO PCDUs regarding the implementation of the passivation function in several LEO missions with different architectures (DET and MPPT solar array power conditioning. In the selection of the solution implemented in the frame of every mission, a key driver is the degree of advance in the test performed over flight representative battery modules regarding their safe behavior when deeply depleted after a long period in orbit with the passivation applied over the spacecraft.

  14. El petróleo como repelente de Phlebotomus

    Directory of Open Access Journals (Sweden)

    Marshall Hertig

    1943-09-01

    Full Text Available Se ha probado el repelente del petróleo contra el Phlebotomus verrucarum. Se echó varias veces petróleo en las paredes exteriores y en el suelo alrededor de casas en la zona verrucógena del Rímac, donde son abundantes las titiras. Inmediatamente después de cada petrolización se redujeron a números insignificantes las titiras dentro de las casas, efecto que duró aproximadamente una semana.

  15. Nitrogen and plant population change radiation capture and utilization capacity of sunflower in semi-arid environment.

    Science.gov (United States)

    Awais, Muhammad; Wajid, Aftab; Bashir, Muhammad Usman; Habib-Ur-Rahman, Muhammad; Raza, Muhammad Aown Sammar; Ahmad, Ashfaq; Saleem, Muhammad Farrukh; Hammad, Hafiz Mohkum; Mubeen, Muhammad; Saeed, Umer; Arshad, Muhammad Naveed; Fahad, Shah; Nasim, Wajid

    2017-07-01

    sunflower. High temperature during the flowering stage in 2013 shortened the crop maturity duration, which reduced the LAI, leaf area duration (LAD), crop growth rate (CGR), TDM, AY, Fi, Sa, and RUE of sunflower. Our results clearly revealed that RUE was enhanced as plant population and N application rates were increased and biomass assimilation in semi-arid environments varied with radiation capture capacity of sunflower.

  16. Environment

    International Nuclear Information System (INIS)

    McIntyre, A.D.; Turnbull, R.G.H.

    1992-01-01

    The development of the hydrocarbon resources of the North Sea has resulted in both offshore and onshore environmental repercussions, involving the existing physical attributes of the sea and seabed, the coastline and adjoining land. The social and economic repercussions of the industry were equally widespread. The dramatic and speedy impact of the exploration and exploitation of the northern North Sea resources in the early 1970s, on the physical resources of Scotland was quickly realised together with the concern that any environmental and social damage to the physical and social fabric should be kept to a minimum. To this end, a wide range of research and other activities by central and local government, and other interested agencies was undertaken to extend existing knowledge on the marine and terrestrial environments that might be affected by the oil and gas industry. The outcome of these activities is summarized in this paper. The topics covered include a survey of the marine ecosystems of the North Sea, the fishing industry, the impact of oil pollution on seabirds and fish stocks, the ecology of the Scottish coastline and the impact of the petroleum industry on a selection of particular sites. (author)

  17. Specification of electron radiation environment at GEO and MEO for surface charging estimates

    Science.gov (United States)

    Ganushkina, N.; Dubyagin, S.; Mateo Velez, J. C.; Liemohn, M. W.

    2017-12-01

    A series of anomalies at GEO have been attributed to electrons of energy below 100 keV, responsible for surface charging. The process at play is charge deposition on covering insulating surfaces and is directly linked to the space environment at a time scale of a few tens of seconds. Even though modern satellites benefited from the analysis of past flight anomalies and losses, it appears that surface charging remains a source of problems. Accurate specification of the space environment at different orbits is of a key importance. We present the operational model for low energy (index. The presented model provides the low energy electron flux at all L-shells and at all satellite orbits, when necessary. IMPTAM is used to simulate the fluxes of low energy electrons inside the Earth's magnetosphere at the time of severe events measured on LANL satellites at GEO. There is no easy way to say what will be the flux of keV electrons at MEO when surface charging events are detected at GEO than to use a model. The maximal electron fluxes obtained at MEO (L = 4.6) within a few tens of minutes hours following the LANL events at GEO have been extracted to feed a database of theoretical/numerical worst-case environments for surface charging at MEO. All IMPTAM results are instantaneous, data have not been average. In order to validate the IMPTAM output at MEO, we conduct the statistical analysis of measured electron fluxes onboard Van Allen Probes (ECT HOPE (20 eV-45 keV) and ECT MagEIS (30 - 300 keV) at distances of 4.6 Re. IMPTAM e- flux at MEO is used as input to SPIS, the Spacecraft Plasma Interaction System Software toolkit for spacecraft-plasma interactions and spacecraft charging modelling (http://dev.spis.org/projects/spine/home/spis). The research leading to these results was funded by the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement No 606716 SPACESTORM and by the European Union's Horizon 2020 research and innovation programme under