WorldWideScience

Sample records for fallout debris originating

  1. Determination of Volatility and Element Fractionation in Glassy Fallout Debris by SIMS

    Energy Technology Data Exchange (ETDEWEB)

    Williamson, Todd L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tenner, Travis Jay [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bonamici, Chloe Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kinman, William Scott [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollington, Anthony Douglas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Steiner, Robert Ernest [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-10

    The purpose of this report is to characterize glassy fallout debris using the Trinity Test and then characterize the U-isotopes of U3O8 reference materials that contain weaponized debris.

  2. Quantifying sources of fine sediment supplied to post-fire debris flows using fallout radionuclide tracers

    Science.gov (United States)

    Smith, Hugh; Sheridan, Gary; Nyman, Petter; Child, David; Lane, Patrick; Hotchkis, Michael

    2013-04-01

    The supply of fine sediment and ash has been identified as an important factor contributing to the initiation of runoff-generated debris flows after fire. However, despite the significance of fines for post-fire debris flow generation, no investigations have sought to quantify sources of this material in debris flow affected catchments. In this study, we employ fallout radionuclides (Cs-137, excess Pb-210 and Pu-239,240) as tracers to measure proportional contributions of fine sediment (bank sources to levee and terminal fan deposits formed by post-fire debris flows in two forest catchments in southeastern Australia. While Cs-137 and excess Pb-210 have been widely used in sediment tracing studies, application of Pu as a tracer represents a recent development and was limited to only one catchment. The estimated range in hillslope surface contributions of fine sediment to individual debris flow deposits in each catchment was 22-69% and 32-74%, respectively. No systematic change in the source contributions to debris flow deposits was observed with distance downstream from channel initiation points. Instead, spatial variability in source contributions was largely influenced by the pattern of debris flow surges forming the deposits. Linking the sediment tracing with interpretation of depositional evidence allowed reconstruction of temporal sequences in sediment source contributions to debris flow surges. Hillslope source inputs dominated most elevated channel deposits such as marginal levees that were formed under peak flow conditions. This indicated the importance of hillslope runoff and sediment supply for debris flow generation in both catchments. In contrast, material stored within channels that was deposited during subsequent surges was predominantly channel-derived. The results demonstrate that fallout radionuclide tracers may provide unique information on the changing source contributions of fine sediment during debris flow events.

  3. Fallout

    International Nuclear Information System (INIS)

    Fradkin, P.L.

    1989-01-01

    When the United States government conducted atmospheric nuclear tests in southern Nevada during the 1950s and early 1960s, radioactive fallout drifted downwind onto citizens. The case of Irene Allen v. The United States of America, filed on August 30, 1979, brought to public awareness the plight of residents of Nevada, Utah, and Arizona. Within the context of the trial, this book provides an overview of the development and atmospheric testing of nuclear weapons by the United States, focusing on Shot Harry, the most radioactive of the 105 atmospheric tests conducted from 1951 to 1962

  4. GLODEP2: a computer model for estimating gamma dose due to worldwide fallout of radioactive debris

    International Nuclear Information System (INIS)

    Edwards, L.L.; Harvey, T.F.; Peterson, K.R.

    1984-03-01

    The GLODEP2 computer code provides estimates of the surface deposition of worldwide radioactivity and the gamma-ray dose to man from intermediate and long-term fallout. The code is based on empirical models derived primarily from injection-deposition experience gained from the US and USSR nuclear tests in 1958. Under the assumption that a nuclear power facility is destroyed and that its debris behaves in the same manner as the radioactive cloud produced by the nuclear weapon that attached the facility, predictions are made for the gamma does from this source of radioactivity. As a comparison study the gamma dose due to the atmospheric nuclear tests from the period of 1951 to 1962 has been computed. The computed and measured values from Grove, UK and Chiba, Japan agree to within a few percent. The global deposition of radioactivity and resultant gamma dose from a hypothetical strategic nuclear exchange between the US and the USSR is reported. Of the assumed 5300 Mton in the exchange, 2031 Mton of radioactive debris is injected in the atmosphere. The highest estimated average whole body total integrated dose over 50 years (assuming no reduction by sheltering or weathering) is 23 rem in the 30 to 50 degree latitude band. If the attack included a 100 GW(e) nuclear power industry as targets in the US, this dose is increased to 84.6 rem. Hotspots due to rainfall could increase these values by factors of 10 to 50

  5. Study of the fallout of artificial iron-55. Application to the evaluation of the fallout of natural iron of stratospheric origin

    International Nuclear Information System (INIS)

    Hoang Chi Trach

    1969-01-01

    The object of this work is to study the iron-55 fallout to establish the world balance of this radioelement. The utilisation of this tracer enables the calculation of the input of natural iron of stratospheric origin to the Earth and the input through the atmosphere of natural iron to the oceans. We have shown that: iron-55 is essentially produced in nuclear explosions according to the 56 Fe(n,2n) 55 Fe reaction; the iron-55 fallout obeys a 'stratospheric pattern' with a decay period between 9 and 11 months; by surface unit and at the same latitude, this fallout is 3.5 times more important on the Eastern part of the Northern Atlantic than over France. By comparison with the strontium-90 fallout, we established the world balance of the iron-55 fallout in the 1962-1965 period. This balance amounts to approximately 50 mega-curies for the iron-55 introduced into the atmosphere; 25.3 mega-curies of which fall down on the Earth during this period. We estimated at 6 x 10 6 tons per year the input of natural iron of stratospheric origin to the Earth and at 1.2 x 10 7 tons per year the input through the atmosphere of natural iron to the oceans. This latter figure represents 13 to 38 per cent of the amount of iron incorporated annually in the pelagic sediments. (author) [fr

  6. On the debris-level origins of adhesive wear.

    Science.gov (United States)

    Aghababaei, Ramin; Warner, Derek H; Molinari, Jean-François

    2017-07-25

    Every contacting surface inevitably experiences wear. Predicting the exact amount of material loss due to wear relies on empirical data and cannot be obtained from any physical model. Here, we analyze and quantify wear at the most fundamental level, i.e., wear debris particles. Our simulations show that the asperity junction size dictates the debris volume, revealing the origins of the long-standing hypothesized correlation between the wear volume and the real contact area. No correlation, however, is found between the debris volume and the normal applied force at the debris level. Alternatively, we show that the junction size controls the tangential force and sliding distance such that their product, i.e., the tangential work, is always proportional to the debris volume, with a proportionality constant of 1 over the junction shear strength. This study provides an estimation of the debris volume without any empirical factor, resulting in a wear coefficient of unity at the debris level. Discrepant microscopic and macroscopic wear observations and models are then contextualized on the basis of this understanding. This finding offers a way to characterize the wear volume in atomistic simulations and atomic force microscope wear experiments. It also provides a fundamental basis for predicting the wear coefficient for sliding rough contacts, given the statistics of junction clusters sizes.

  7. Radioecological transfer of {sup 137}Cs from ground deposition to man from Chernobyl debris and from nuclear weapons fallout in different Swedish populations

    Energy Technology Data Exchange (ETDEWEB)

    Raeaef, C.L. [Malmoe Univ. Hospital, Lund Univ., Dept. of Radiation Physics, Malmoe (Sweden)

    2005-07-01

    A comparison of the estimated committed effective dose per unit activity deposition on ground was made between different critical groups in Sweden. The time-integrated aggregate transfer of {sup 137}Cs for the global fallout was 2-3 times higher than from Chernobyl debris for Swedish urban populations. For reindeer herders this difference is even more marked, with a factor of three to four higher time-integrated transfer factor of nuclear weapons fallout. Considering the transfer of Chernobyl {sup 137}Cs debris the time-integrated transfer factor appears to be more than 25 times higher for reindeer herders in Sweden than for the urban reference groups. An even more pronounced relative difference between the time integrated aggregate transfer was observed between reindeer herders and urban reference populations for the pre-Chernobyl fallout (a factor of 30). The projected committed effective dose from internal contamination of Chernobyl {sup 137}Cs per unit activity deposition is observed to be 2030 {mu}Sv/kBq m{sup -2}. The highest values in Sweden are obtained for reindeer herders with an estimated radioecological transfer of 0.5 mSv/kBq m{sup -2}. (au)

  8. Radioecological transfer of 137Cs from ground deposition to man from Chernobyl debris and from nuclear weapons fallout in different Swedish populations

    International Nuclear Information System (INIS)

    Raeaef, C.L.

    2005-01-01

    A comparison of the estimated committed effective dose per unit activity deposition on ground was made between different critical groups in Sweden. The time-integrated aggregate transfer of 137 Cs for the global fallout was 2-3 times higher than from Chernobyl debris for Swedish urban populations. For reindeer herders this difference is even more marked, with a factor of three to four higher time-integrated transfer factor of nuclear weapons fallout. Considering the transfer of Chernobyl 137 Cs debris the time-integrated transfer factor appears to be more than 25 times higher for reindeer herders in Sweden than for the urban reference groups. An even more pronounced relative difference between the time integrated aggregate transfer was observed between reindeer herders and urban reference populations for the pre-Chernobyl fallout (a factor of 30). The projected committed effective dose from internal contamination of Chernobyl 137 Cs per unit activity deposition is observed to be 2030 μSv/kBq m -2 . The highest values in Sweden are obtained for reindeer herders with an estimated radioecological transfer of 0.5 mSv/kBq m -2 . (au)

  9. Combining microscopy with spectroscopic and chemical methods for tracing the origin of atmospheric fallouts from mining sites

    Energy Technology Data Exchange (ETDEWEB)

    Navel, Aline; Uzu, Gaëlle; Spadini, Lorenzo [University Grenoble Alpes — LTHE UMR 5564–CNRS-INSU/UGA/INPG/IRD, 1025 rue de la Piscine, DU BP53 - 38041 Grenoble CEDEX 9 (France); Sobanska, Sophie [LASIR, (UMR CNRS 8516), Université de Lille 1, Bât. C5, 59655 Villeneuve d' Ascq CEDEX (France); Martins, Jean M.F., E-mail: jean.martins@yujf-grenoble.fr [University Grenoble Alpes — LTHE UMR 5564–CNRS-INSU/UGA/INPG/IRD, 1025 rue de la Piscine, DU BP53 - 38041 Grenoble CEDEX 9 (France)

    2015-12-30

    Highlights: • Numerous ancient mines are left over without specific care for contaminated wastes. • Sources similarity makes the tracing of the origin of metallic fallouts challenging. • Physico-chemical fingerprints of all metal-source sites and fallouts were established. • Combining physical/chemical methods allowed discriminating polluted fallouts origin. • A Hierarchical cluster analysis permitted to identify the dominant particles source. - Abstract: Populations living close to mining sites are often exposed to important heavy metal concentrations, especially through atmospheric fallouts. Identifying the main sources of metal-rich particles remains a challenge because of the similarity of the particle signatures from the polluted sites. This work provides an original combination of physical and chemical methods to determine the main sources of airborne particles impacting inhabited zones. Raman microspectrometry (RMS), X-ray diffraction (DRX), morphology analyses by microscopy and chemical composition were assessed. Geochemical analysis allowed the identification of target and source areas; XRD and RMS analysis identified the main mineral phases in association with their metal content and speciation. The characterization of the dominant minerals was combined with particle morphology analysis to identify fallout sources. The complete description of dust morphologies permitted the successful determination of a fingerprint of each source site. The analysis of these chemical and morphological fingerprints allowed identification of the mine area as the main contributor of metal-rich particles impacting the inhabited zone. In addition to the identification of the main sources of airborne particles, this study will also permit to better define the extent of polluted zones requiring remediation or protection from eolian erosion inducing metal-rich atmospheric fallouts.

  10. Combining microscopy with spectroscopic and chemical methods for tracing the origin of atmospheric fallouts from mining sites

    International Nuclear Information System (INIS)

    Navel, Aline; Uzu, Gaëlle; Spadini, Lorenzo; Sobanska, Sophie; Martins, Jean M.F.

    2015-01-01

    Highlights: • Numerous ancient mines are left over without specific care for contaminated wastes. • Sources similarity makes the tracing of the origin of metallic fallouts challenging. • Physico-chemical fingerprints of all metal-source sites and fallouts were established. • Combining physical/chemical methods allowed discriminating polluted fallouts origin. • A Hierarchical cluster analysis permitted to identify the dominant particles source. - Abstract: Populations living close to mining sites are often exposed to important heavy metal concentrations, especially through atmospheric fallouts. Identifying the main sources of metal-rich particles remains a challenge because of the similarity of the particle signatures from the polluted sites. This work provides an original combination of physical and chemical methods to determine the main sources of airborne particles impacting inhabited zones. Raman microspectrometry (RMS), X-ray diffraction (DRX), morphology analyses by microscopy and chemical composition were assessed. Geochemical analysis allowed the identification of target and source areas; XRD and RMS analysis identified the main mineral phases in association with their metal content and speciation. The characterization of the dominant minerals was combined with particle morphology analysis to identify fallout sources. The complete description of dust morphologies permitted the successful determination of a fingerprint of each source site. The analysis of these chemical and morphological fingerprints allowed identification of the mine area as the main contributor of metal-rich particles impacting the inhabited zone. In addition to the identification of the main sources of airborne particles, this study will also permit to better define the extent of polluted zones requiring remediation or protection from eolian erosion inducing metal-rich atmospheric fallouts.

  11. Types and Origins of Debris Found on Maui Shorelines: Implications for Mitigation Policies and Strategies

    Science.gov (United States)

    Blickley, L.; Currie, J. J.; Kaufman, G. D.

    2016-02-01

    Marine debris is an identified concern for coastal areas and is known to accumulate in large quantities in the North Pacific Ocean. The proximity of the Main Hawaiian Islands to these "garbage patches" represents an ongoing concern with little understanding of debris origins or efficacy of current mitigation policies. Debris accumulation surveys were conducted monthly between October 2013 and August 2014 and daily during January 2015 at 3 beaches on Maui's coastline. Debris accumulation rates, loads, and sources varied between sites and were influenced by both environmental and anthropogenic factors. Debris accumulation was strongly influenced by the temporal scale of sampling, with daily surveys showing a significant increase in accumulation rate. Plastics were the most common debris item at each site ranging from local, land-based debris including cigarette butts, straws, and food wrappers, to foreign, ocean-based debris such as oyster spacer tubes and hagfish traps. The results of this study indicate that the passage of a tobacco free beaches bill on Maui has not significantly reduced the amount of tobacco related debris. Alternatively, a ban on plastic grocery bags has eliminated this type of debris from Maui's shorelines, with no bags found at any of the sampling sites. The wide spread origins of collected debris further suggests that mitigation strategies to reduce debris will need to take place across hundreds of local municipalities. The efficacy of marine debris policies furthermore depends on enforcement and implementation strategy, as current results suggest policy enforcement at the producer level affords more effective results than that at the consumer level. Local debris mitigation actions have nevertheless been shown to affect debris loads, and municipalities are therefore encouraged to adopt a holistic combination of policy, community-based debris removal programs, increased public awareness, and ongoing monitoring to address marine debris.

  12. Radioactive fallout

    International Nuclear Information System (INIS)

    Christensen, G.C.

    1976-01-01

    The formation of the fireball following a nuclear or thermonuclear explosion, and its ascent and cooling are described. Local and global fallout are discussed, and the differing behaviour of fallout from the troposphere and stratosphere explained. The monthly and accumulated fallout of sr90 and its distribution in the Northern and Southern hemispheres is used as an illustration. The accumulation of fallout and its distribution and concentration by food chains is also discussed, using Sr 90, Cs 137 and I 131 as examples. (JIW)

  13. Counter-orbiting tidal debris as the origin of the MW DoS

    Directory of Open Access Journals (Sweden)

    Pawlowski M.S.

    2012-02-01

    Full Text Available The Milky Way satellite galaxies show a phase-space distribution that is not expected from the standard scenario of galaxy formation. This is a strong hint at them being of tidal origin, which would naturally explain their spacial distribution in a disc of satellites. It is shown that also their orbital directions can be reproduced with the debris of galaxy collisions. Both co- and counter-orbiting satellites are formed naturally in merger and fly-by interactions.

  14. Rapid Debris Analysis Project Task 3 Final Report - Sensitivity of Fallout to Source Parameters, Near-Detonation Environment Material Properties, Topography, and Meteorology

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, Peter [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-01-24

    This report describes the sensitivity of predicted nuclear fallout to a variety of model input parameters, including yield, height of burst, particle and activity size distribution parameters, wind speed, wind direction, topography, and precipitation. We investigate sensitivity over a wide but plausible range of model input parameters. In addition, we investigate a specific example with a relatively narrow range to illustrate the potential for evaluating uncertainties in predictions when there are more precise constraints on model parameters.

  15. Radioactive fallout

    International Nuclear Information System (INIS)

    Shapiro, C.S.; Harvey, T.F.; Peterson, K.R.

    1985-12-01

    Potential radiation doses from several scenarios involving nuclear attack on an unsheltered United States population are calculated for local, intermediate time scale and long-term fallout. Dose estimates are made for both a normal atmosphere and an atmosphere perturbed by smoke produced by massive fires. A separate section discusses the additional doses from nuclear fuel facilities, were they to be targeted in an attack. Finally, in an appendix the direct effects of fallout on humans are considered. These include effects of sheltering and biological repair of damage from chronic doses. 21 refs., 10 figs., 11 tabs

  16. Age, origin and evolution of Antarctic debris-covered glaciers: Implications for landscape evolution and long-term climate change

    Science.gov (United States)

    Mackay, Sean Leland

    Antarctic debris-covered glaciers are potential archives of long-term climate change. However, the geomorphic response of these systems to climate forcing is not well understood. To address this concern, I conducted a series of field-based and numerical modeling studies in the McMurdo Dry Valleys of Antarctica (MDV), with a focus on Mullins and Friedman glaciers. I used data and results from geophysical surveys, ice-core collection and analysis, geomorphic mapping, micro-meteorological stations, and numerical-process models to (1) determine the precise origin and distribution of englacial and supraglacial debris within these buried-ice systems, (2) quantify the fundamental processes and feedbacks that govern interactions among englacial and supraglacial debris, (3) establish a process-based model to quantify the inventory of cosmogenic nuclides within englacial and supraglacial debris, and (4) isolate the governing relationships between the evolution of englacial /supraglacial debris and regional climate forcing. Results from 93 field excavations, 21 ice cores, and 24 km of ground-penetrating radar data show that Mullins and Friedman glaciers contain vast areas of clean glacier ice interspersed with inclined layers of concentrated debris. The similarity in the pattern of englacial debris bands across both glaciers, along with model results that call for negligible basal entrainment, is best explained by episodic environmental change at valley headwalls. To constrain better the timing of debris-band formation, I developed a modeling framework that tracks the accumulation of cosmogenic 3He in englacial and supraglacial debris. Results imply that ice within Mullins Glacier increases in age non-linearly from 12 ka to ˜220 ka in areas of active flow (up to >> 1.6 Ma in areas of slow-moving-to-stagnant ice) and that englacial debris bands originate with a periodicity of ˜41 ka. Modeling studies suggest that debris bands originate in synchronicity with changes in

  17. Composition and potential origin of marine debris stranded in the Western Indian Ocean on remote Alphonse Island, Seychelles

    International Nuclear Information System (INIS)

    Duhec, Aurélie V.; Jeanne, Richard F.; Maximenko, Nikolai; Hafner, Jan

    2015-01-01

    The abundance, composition, and potential sources of marine debris were investigated on remote Alphonse Island, during the austral winter 2013. A total of 4743 items, weighing 142 kg, were removed from 1 km of windward beach, facing the prevailing southeasterly trade winds. Our study demonstrates the prevalence of plastic debris as a world-wide marine contaminant. Characteristics of the debris suggest it originated primarily from land-based sources. To determine their potential geographic sources we used the Surface Current from Diagnostic model of near-surface ocean currents, forced by satellite sea level and wind data. While preliminary evidence indicated the Southeast Asia to be the main source of the flotsam, the model highlighted Somalia as another potential primary source. Our study concludes that most of the collected debris entered the sea as a result of inadequate waste management and demonstrates how anthropogenic waste can negatively impact even the most remote environments

  18. Human metabolism and ecological transfer of radioactive caesium. Comparative studies of Chernobyl debris and nuclear weapons fallout, in southern Sweden and in Bryansk, Russia

    International Nuclear Information System (INIS)

    Raeaef, C.L.

    2000-05-01

    The whole-body content of radiocaesium was measured in a South Swedish urban group of people residing in the city of Lund between 1960 and 1994. The results from the survey have been analysed in order to estimate the ecological half time, T eff,eco of fallout radiocaesium, and the aggregate transfer from ground deposition to man in the region. After 1987, the biological half times, T e of 137 Cs and 40 K in man were also determined in the reference group through whole-body content measurements in combination with 24-hour urine sampling. Relationships between 24-hour urinary excretion and body burden of 137 Cs in the group together with data from the literature were then applied to urine samples collected in 1994 and 1995 from adult subjects living in the highly contaminated region of Bryansk, Russia, in order to estimate their average body burden of 137 Cs. The equivalent biological half-time for 137 Cs in females of the Lund reference group was, on average 66±3 d, which agrees with other findings, whereas the value for the males, 81±4 d, was, on average, significantly lower than what is found in the literature. This is partly explained by the elevated mean age and relatively low mean body muscle mass of the males investigated. The 137 Cs from nuclear weapons tests in the 1950s and 1960s still gave a significant contribution to the total 137 Cs levels in man during the post-Chernobyl study period (1987-1994). About 10% of the peak post-Chernobyl concentration level of 137 Cs (3.5-4 Bq/kg) in 1987, was attributed to pre-Chernobyl 137 Cs. The effective ecological half-time for 137 Cs from Chernobyl was found to be 1.8±0.2 y. The time-integrated aggregate transfer of 137 Cs from ground deposition to mean activity concentration in man was estimated to be 0.4 Bq/kg/kBq/m 2 . These values may be compared with an effective ecological half-time of 1.3 years found in the Lund reference group in the 1960s, and in time-integrated aggregate transfer factor of 4.4 Bq

  19. Human metabolism and ecological transfer of radioactive caesium: Comparative studies of Chernobyl debris and nuclear weapons fallout, in Southern Sweden and in Bryansk, Russia

    Science.gov (United States)

    Raaf, Christopher Leopold

    The whole-body content of radiocaesium was measured in a South-Swedish urban group of people residing in the city of Lund (55.7°N, 13.2°E) between 1960 and 1994. The results from the survey have been analysed in order to estimate the ecological half-time, Teff,eco, of fallout radiocaesium and the aggregate transfer from ground deposition to man in the region. After 1987, the biological half-times, Ts, of 137Cs and 40K in man were also determined in the reference group through whole-body content measurements in combination with 24-hour urine sampling. Relationships between 24-hour urinary excretion and body burden of 137Cs in the group together with data from the literature were then applied to urine samples collected in 1994 and 1995 from adult subjects living in the highly contaminated region of Bryansk, Russia, in order to estimate their average body burden of 137Cs. The equivalent biological half-time for 137Cs in females of the Lund reference group was, on average (+/-1 WSE), 66 +/- 3 d, which agrees with other findings, whereas the value for the males, 81 +/- 4 d, was, on average, significantly lower than what is found in the literature. This is partly explained by the elevated mean age and relatively low mean body muscle mass of the males investigated in the group during the post-Chernobyl study period. The effective ecological half-time for 137Cs from Chernobyl was found to be 1.8 +/- 0.2 y. The aggregate transfer of 137Cs from deposition to mean activity concentration in man was estimated to be 1.7 Bq kg-1/kBq m-2. These vales may be compared with an effective ecological half-time of 1.3 years found in the reference group in the 1960s, and an aggregate transfer factor of 9.8 Bq kg-1/kBq m-2. The average committed effective dose from ingested 137Cs Chernobyl fallout in the study group was estimated to be 0.02 mSv and from the nuclear weapons fallout to 0.20 mSv. The estimates of whole-body content of 137Cs in the Russian subjects obtained through

  20. Human metabolism and ecological transfer of radioactive caesium. Comparative studies of Chernobyl debris and nuclear weapons fallout, in southern Sweden and in Bryansk, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Raeaef, C.L

    2000-05-01

    The whole-body content of radiocaesium was measured in a South Swedish urban group of people residing in the city of Lund between 1960 and 1994. The results from the survey have been analysed in order to estimate the ecological half time, T{sub eff,eco} of fallout radiocaesium, and the aggregate transfer from ground deposition to man in the region. After 1987, the biological half times, T{sub e} of {sup 137}Cs and {sup 40}K in man were also determined in the reference group through whole-body content measurements in combination with 24-hour urine sampling. Relationships between 24-hour urinary excretion and body burden of {sup 137}Cs in the group together with data from the literature were then applied to urine samples collected in 1994 and 1995 from adult subjects living in the highly contaminated region of Bryansk, Russia, in order to estimate their average body burden of {sup 137}Cs. The equivalent biological half-time for {sup 137}Cs in females of the Lund reference group was, on average 66{+-}3 d, which agrees with other findings, whereas the value for the males, 81{+-}4 d, was, on average, significantly lower than what is found in the literature. This is partly explained by the elevated mean age and relatively low mean body muscle mass of the males investigated. The {sup 137}Cs from nuclear weapons tests in the 1950s and 1960s still gave a significant contribution to the total {sup 137}Cs levels in man during the post-Chernobyl study period (1987-1994). About 10% of the peak post-Chernobyl concentration level of {sup 137}Cs (3.5-4 Bq/kg) in 1987, was attributed to pre-Chernobyl {sup 137}Cs. The effective ecological half-time for {sup 137}Cs from Chernobyl was found to be 1.8{+-}0.2 y. The time-integrated aggregate transfer of {sup 137}Cs from ground deposition to mean activity concentration in man was estimated to be 0.4 Bq/kg/kBq/m{sup 2}. These values may be compared with an effective ecological half-time of 1.3 years found in the Lund reference group in

  1. Composition and potential origin of marine debris stranded in the Western Indian Ocean on remote Alphonse Island, Seychelles.

    Science.gov (United States)

    Duhec, Aurélie V; Jeanne, Richard F; Maximenko, Nikolai; Hafner, Jan

    2015-07-15

    The abundance, composition, and potential sources of marine debris were investigated on remote Alphonse Island, during the austral winter 2013. A total of 4743 items, weighing 142 kg, were removed from 1 km of windward beach, facing the prevailing southeasterly trade winds. Our study demonstrates the prevalence of plastic debris as a world-wide marine contaminant. Characteristics of the debris suggest it originated primarily from land-based sources. To determine their potential geographic sources we used the Surface Current from Diagnostic model of near-surface ocean currents, forced by satellite sea level and wind data. While preliminary evidence indicated the Southeast Asia to be the main source of the flotsam, the model highlighted Somalia as another potential primary source. Our study concludes that most of the collected debris entered the sea as a result of inadequate waste management and demonstrates how anthropogenic waste can negatively impact even the most remote environments. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Plutonium fallout at Fayetteville, AR

    International Nuclear Information System (INIS)

    Sandoval, D.N.; Essien, I.O.; Kuroda, P.K.

    1985-01-01

    It is well established that atmospheric Pu fallout has its origin in the testing of nuclear devices and satellite accidents. Monitoring injections of Pu during the testing of nuclear devices can be useful in characterizing the detonation and subsequently tagging its global fallout. Since Pu uptake pathway into humans is mainly through the respiratory and digestive systems, it is important to know about the behavior of Pu in the atmosphere. Snow and rain samples were collected between Jan 1981 and April 1983, and analyzed for plutonium

  3. Direct-to-consumer DNA testing: the fallout for individuals and their families unexpectedly learning of their donor conception origins.

    Science.gov (United States)

    Crawshaw, Marilyn

    2017-07-11

    Increasing numbers of donor-conceived individuals (and/or parents) are seeking individuals genetically related through donor conception. One route is through 'direct-to-consumer' (DTC) DNA testing, prompting calls for fertility services to alert donors and prospective parents to the increasing unsustainability of anonymity and secrecy. The complexity of interpreting DNA results in this context has also been discussed, including their lack of absolute certainty, as has the need for professional and peer support. This commentary highlights a different 'threat', from individuals learning of their donor-conception origins through the use of such tests by themselves or relatives for such purposes as genealogy or health checks. It illustrates the personal complexities faced by three older women and their families on learning not only of their genetic relationship to each other but also to 15 more donor-related siblings. DTC DNA services are a growing feature of modern life. This commentary raises ethical questions about their responsibilities towards those inadvertently learning of donor conception origins and the responsibilities of fertility services to inform prospective parents and donors of this new phenomenon. Considerations of how and when parents should tell their children of their donor-conception origins here instead become how and when children should inform their parents.

  4. COMETARY ORIGIN OF THE ZODIACAL CLOUD AND CARBONACEOUS MICROMETEORITES. IMPLICATIONS FOR HOT DEBRIS DISKS

    International Nuclear Information System (INIS)

    Nesvorny, David; Levison, Harold F.; Bottke, William F.; Jenniskens, Peter; Vokrouhlicky, David; Gounelle, Matthieu

    2010-01-01

    The zodiacal cloud is a thick circumsolar disk of small debris particles produced by asteroid collisions and comets. Their relative contribution and how particles of different sizes dynamically evolve to produce the observed phenomena of light scattering, thermal emission, and meteoroid impacts are unknown. Until now, zodiacal cloud models have been phenomenological in nature, composed of ad hoc components with properties not understood from basic physical processes. Here, we present a zodiacal cloud model based on the orbital properties and lifetimes of comets and asteroids, and on the dynamical evolution of dust after ejection. The model is quantitatively constrained by Infrared Astronomical Satellite (IRAS) observations of thermal emission, but also qualitatively consistent with other zodiacal cloud observations, with meteor observations, with spacecraft impact experiments, and with properties of recovered micrometeorites (MMs). We find that particles produced by Jupiter-family comets (JFCs) are scattered by Jupiter before they are able to orbitally decouple from the planet and drift down to 1 AU. Therefore, the inclination distribution of JFC particles is broader than that of their source comets and leads to good fits to the broad latitudinal distribution of fluxes observed by IRAS. We find that 85%-95% of the observed mid-infrared emission is produced by particles from JFCs and 100 μm undergo a further collisional cascade with smaller fragments being progressively more affected by Poynting-Robertson (PR) drag. Upon reaching D -1 mean for D = 100-200 μm with ∼12 km s -1 being the most common case), many JFC grains should survive frictional heating and land on Earth's surface. This explains why most MMs collected in antarctic ice have primitive carbonaceous composition. The present mass of the inner zodiacal cloud at 19 g, mainly in D = 100-200 μm particles. The inner zodiacal cloud should have been >10 4 times brighter during the Late Heavy Bombardment

  5. Real hazards of nuclear fallout

    Energy Technology Data Exchange (ETDEWEB)

    Knox, J.B.; Shapiro, C.S.

    1986-05-01

    The paper discusses an article by Carl Sagan entitled ''On minimizing the consequences of nuclear war'' (Nature 317 485 Oct 1985), in the light of the authors' own work on global fallout. Consequences of local fallout, human impact of local fallout, and global fallout calculations using computer models, are all described. (U.K.).

  6. Mechanistic and morphological origins of ultra-high molecular weight polyethylene wear debris in total joint replacement prostheses.

    Science.gov (United States)

    Wang, A; Stark, C; Dumbleton, J H

    1996-01-01

    The mechanistic and morphological origins of microscopic wear debris generated from UHMWPE articular surfaces in total joint replacement prostheses are investigated in this study. It was found experimentally that the molecular chain structure at the articulating surface of UHMWPE undergoes a re-organization process due to strain accumulation caused by surface traction. This molecular re-organization process creates a fibre-like surface texture that exhibits an anisotropic behaviour similar to a unidirectionally reinforced polymer composite. This composite responds to stresses favourably if loaded along the fibre axis but unfavourably if loaded off axis. Due to the very complex multi-axial motion/loading nature at the articular surfaces in total joint replacements, the stress tensors applied to each localized asperity contact area continuously change their directions and magnitudes. These changes in the localized stress field create an off-axis loading situation at each localized contact zone with respect to the orientation of the molecular chains. Depending on the off-axis angle, failure of the molecular structure occurs in three different ways: tensile rupture at very small off-axis angles, shear rupture at intermediate off-axis angles and transverse splitting at large off-axis angles. These failure mechanisms all produce similar fibre-like wear debris. However, the failure stresses differ significantly among the three modes. According to this molecular wear theory, the preferred polymer microstructure for optimal wear resistance would be a three-dimensionally strong network connected by covalent bonds between molecular chains. For UHMWPE, a three-dimensional molecular network can be created by radiation induced cross-linking. Experiments conducted on both gamma irradiated and unirradiated UHMWPE specimens using a linear wear machine and multi-axial joint simulators confirmed the validity of the molecular wear theory.

  7. Radioactive fall-out from the Chernobyl disaster, and its aftermath in Central Europe

    International Nuclear Information System (INIS)

    Mueller-Broich, A.

    1986-01-01

    Radioactive fall-out originating from the disaster of the nuclear power station at Chernobyl in the Soviet Union was measured in Bavaria and other parts of Central Europe. Nuclide composition and spatial distribution of fall-out are presented and compared to radioactive debris from nuclear bomb tests. The uptake of radioactive material by plants and its passage into human food is discussed. The contribution of direct deposition, redistribution within plants and transfer from soil into plants is considered. Factors determining the paths of radioactive material into milk and meat are outlined. Safety precautions against excessive incorporation of radioactivity issued by the authorities are given. Irradiation of humans from external and internal fall-out is assessed. Nuclides composition is shown to be of major importance only for internal radiation. In view of the dominating abundance of radioiodine and radiocesium the differing physical and biochemical qualities of these nuclides are described in more detail. Finally, the resulting risk of cancer induction including leukemia is considered

  8. Fallout Radioactivity and Epiphytes.

    Science.gov (United States)

    H. T. Odum; George Ann Briscoe; C. B. Briscoe

    1970-01-01

    After relatively high levels of fallout retention were dicovered in the epiphytic mossy forest of the Luquillo Mountains durin 1962, a survey of the distribution of radioactivity in the rain forest system was made with beta counting of 1500 samples supplemented with gamma spectra. High levels, up to 4138 counts per minute per gram, were found mainly in or on green...

  9. Health effects from fallout.

    Science.gov (United States)

    Gilbert, Ethel S; Land, Charles E; Simon, Steven L

    2002-05-01

    This paper primarily discusses health effects that have resulted from exposures received as a result of above-ground nuclear tests, with emphasis on thyroid disease from exposure to 131I and leukemia and solid cancers from low dose rate external and internal exposure. Results of epidemiological studies of fallout exposures in the Marshall Islands and from the Nevada Test Site are summarized, and studies of persons with exposures similar to those from fallout are briefly reviewed (including patients exposed to 131I for medical reasons and workers exposed externally at low doses and low dose rates). Promising new studies of populations exposed in countries of the former Soviet Union are also discussed and include persons living near the Semipalatinsk Test Site in Kazakhstan, persons exposed as a result of the Chernobyl accident, and persons exposed as a result of operations of the Mayak Nuclear Plant in the Russian Federation. Very preliminary estimates of cancer risks from fallout doses received by the United States population are presented.

  10. Nuclear fallout shelter

    International Nuclear Information System (INIS)

    Elton, J.

    1982-01-01

    A nuclear fallout shelter, to be buried below ground level exposing only an access hatch with a cover and ventilators, is constructed of two preformed hollow end sections connected by one or more preformed hollow tubular intermediate sections. The ventilators include a filter for removing radioactive particles from the air entering the shelter. The sections may be moulded shells of glass fibre reinforced plastics material having inwardly directed peripheral end flanges to enable the sections to be bolted together from inside the shelter after they have been positioned in an excavated trench. (author)

  11. Strontium 90 fallout prediction

    International Nuclear Information System (INIS)

    Sarmiento, J.L.; Gwinn, E.

    1986-01-01

    An empirical formula is developed for predicting monthly sea level strontium 90 fallout (F) in the northern hemisphere as a function of time (t), precipitation rate (P), latitude (phi), longitude (lambda), and the sea level concentration of stronium 90 in air (C): F(lambda, phi, t) = C(t, phi)[v /sub d/(phi) + v/sub w/(lambda, phi, t)], where v/sub w/(lambda, phi, t) = a(phi)[P(lambda, phi, t)/P/sub o/]/sup b//sup (//sup phi//sup )/ is the wet removal, v/sub d/(phi) is the dry removal and P 0 is 1 cm/month. The constants v/sub d/, a, and b are determined as functions of latitude by fitting land based observations. The concentration of 90 Sr in air is calculated as a function of the deseasonalized concentration at a reference latitude (C-bar/sub r//sub e//sub f/), the ratio of the observations at the latitude of interest to the reference latitude (R), and a function representing the seasonal trend in the air concentration (1 + g): C-bar(t, phi) = C/sub r//sub e//sub f/(t)R(phi)[1 + g(m, phi)]; m is the month. Zonal trends in C are shown to be relatively small. This formula can be used in conjuction with precipitation observations and/or estimates to predict fallout in the northern hemisphere for any month in the years 1954 to 1974. Error estimates are given; they do not include uncertainty due to errors in precipitation data

  12. Fallout model for system studies

    International Nuclear Information System (INIS)

    Harvey, T.F.; Serduke, F.J.D.

    1979-01-01

    A versatile fallout model was developed to assess complex civil defense and military effect issues. Large technical and scenario uncertainties require a fast, adaptable, time-dependent model to obtain technically defensible fallout results in complex demographic scenarios. The KDFOC2 capability, coupled with other data bases, provides the essential tools to consider tradeoffs between various plans and features in different nuclear scenarios and estimate the technical uncertainties in the predictions. All available data were used to validate the model. In many ways, the capability is unmatched in its ability to predict fallout hazards to a society

  13. The real hazards of nuclear fallout

    International Nuclear Information System (INIS)

    Knox, J.B.; Shapiro, C.S.

    1986-01-01

    The paper discusses an article by Carl Sagan entitled ''On minimizing the consequences of nuclear war'' [Nature 317 485 Oct 1985], in the light of the authors' own work on global fallout. Consequences of local fallout, human impact of local fallout, and global fallout calculations using computer models, are all described. (U.K.)

  14. Woody debris

    Science.gov (United States)

    Donna B. Scheungrab; Carl C. Trettin; Russ Lea; Martin F. Jurgensen

    2000-01-01

    Woody debris can be defined as any dead, woody plant material, including logs, branches, standing dead trees, and root wads. Woody debris is an important part of forest and stream ecosystems because it has a role in carbon budgets and nutrient cycling, is a source of energy for aquatic ecosystems, provides habitat for terrestrial and aquatic organisms, and contributes...

  15. How to Make the 20-cent Fallout Meter

    Energy Technology Data Exchange (ETDEWEB)

    Meade, Roger Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rodriguez, Serena R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Alvarez, Luis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-05-17

    Nobel Prize winner Luis Alvarez published an article on how to build a homemade fallout meter in the November 12, 1961, issue of the Sunday supplement This Week Magazine. A yellowed copy of the article was recently found in the files of the Radiochemistry Group, C-NR, and is reproduced below in its original form.

  16. Late medical consequences of exposure to radioactive fallout

    International Nuclear Information System (INIS)

    Adams, W.H.

    1992-01-01

    Data collected by the Brookhaven Medical Program on the late medical consequences of the exposure to radioactive fallout originated from the detonation of a thermonuclear device on Bikini atoll in Marshall Islands are discussed. (author) 23 refs.; 6 figs.; 9 tabs

  17. Seasonal variation of Sr-90 fallout in Japan through the end of 1983

    International Nuclear Information System (INIS)

    Katsuragi, Yukio; Aoyama, Michio

    1986-01-01

    Time variation of Sr-90 fallout together with that of Cs-137 is given through the end of 1983. The results at 12 stations in Japan indicate that the recent fallout in Japan was mainly derived from the 26th Chinese nuclear detonation. Relatively short stratospheric residence time of radioactive debris was obtained for the 26th Chinese detonation. The activity ratio of Cs-137 to Sr-90 in the fallout ranged from 0.8 to 6.0 with the average at 2.03. It is noted that the activity ratio of Cs-137 to Sr-90 decreased just after the detonation and then it increased. The meridional distribution of Sr-90 fallout over the Japan Islands indicates that it increased from south to north, whereas the amount of precipitation decreased in the same direction. After the thermonuclear detonation, the amount of fallout increased in the following year and the appearance of maximum fallout was delayed by one to two months from normal pattern of the spring maximum. (author)

  18. Nuclear fall-out shelter

    International Nuclear Information System (INIS)

    Lowery, R.J.

    1981-01-01

    An underground nuclear fall-out shelter has a plastics shell which, apart from service and access openings, is waterproof and provided, if desired, with a concrete roof. The shelter has an access opening, an air system, lighting, water storage, sanitation and sewage facilities. (author)

  19. Meteorological requirements and operational fallout prediction techniques for Plowshare nuclear detonations

    International Nuclear Information System (INIS)

    Mueller, H.F.

    1969-01-01

    Meteorological support requirements for Plowshare nuclear detonations are shown to depend on a number of factors. The importance of adequate support to the effective planning and safe conduct of a nuclear detonation is described. An example of the influence of atmospheric conditions on radioactive cloud development and local transport and fallout of radioactive debris is presented. Prediction of the future state of atmospheric wind structure, required for fallout predictions depends on an adequate definition of its initial state and its rate of change. This definition, in turn, is shown to depend on an upper wind-sounding network of appropriate station density. An operational technique currently used for nuclear cratering fallout predictions is described and shown to produce results of useful accuracy. (author)

  20. Meteorological requirements and operational fallout prediction techniques for Plowshare nuclear detonations

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, H F [Air Resources Laboratory, Environmental Science Services Administration, Las Vegas, NV (United States)

    1969-07-01

    Meteorological support requirements for Plowshare nuclear detonations are shown to depend on a number of factors. The importance of adequate support to the effective planning and safe conduct of a nuclear detonation is described. An example of the influence of atmospheric conditions on radioactive cloud development and local transport and fallout of radioactive debris is presented. Prediction of the future state of atmospheric wind structure, required for fallout predictions depends on an adequate definition of its initial state and its rate of change. This definition, in turn, is shown to depend on an upper wind-sounding network of appropriate station density. An operational technique currently used for nuclear cratering fallout predictions is described and shown to produce results of useful accuracy. (author)

  1. Detecting debris flows using ground vibrations

    Science.gov (United States)

    LaHusen, Richard G.

    1998-01-01

    Debris flows are rapidly flowing mixtures of rock debris, mud, and water that originate on steep slopes. During and following volcanic eruptions, debris flows are among the most destructive and persistent hazards. Debris flows threaten lives and property not only on volcanoes but far downstream in valleys that drain volcanoes where they arrive suddenly and inundate entire valley bottoms. Debris flows can destroy vegetation and structures in their path, including bridges and buildings. Their deposits can cover roads and railways, smother crops, and fill stream channels, thereby reducing their flood-carrying capacity and navigability.

  2. Characteristic of microplastics in the atmospheric fallout from Dongguan city, China: preliminary research and first evidence.

    Science.gov (United States)

    Cai, Liqi; Wang, Jundong; Peng, Jinping; Tan, Zhi; Zhan, Zhiwei; Tan, Xiangling; Chen, Qiuqiang

    2017-11-01

    Microplastic pollution has exhibited a global distribution, including seas, lakes, rivers, and terrestrial environment in recent years. However, little attention was paid on the atmospheric environment, though the fact that plastic debris can escape as wind-blown debris was previously reported. Thus, characteristics of microplastics in the atmospheric fallout from Dongguan city were preliminarily studied. Microplastics of three different polymers, i.e., PE, PP, and PS, were identified. Diverse shapes of microplastics including fiber, foam, fragment, and film were found, and fiber was the dominant shape of the microplastics. SEM images illustrated that adhering particles, grooves, pits, fractures, and flakes were the common patterns of degradation. The concentrations of non-fibrous microplastics and fibers ranged from 175 to 313 particles/m 2 /day in the atmospheric fallout. Thus, dust emission and deposition between atmosphere, land surface, and aquatic environment were associated with the transportation of microplastics.

  3. Radioactive fallout in the southern hemisphere from nuclear weapons tests

    International Nuclear Information System (INIS)

    Moroney, J.R.

    1979-11-01

    Fallout in the southern hemisphere, and its origins in the national programs of atmospheric nuclear weapons testing in both hemispheres, are reviewed. Of the 390 nuclear tests conducted in the atmosphere to date, 53 were carried out in the southern hemisphere and it is the second phase of these, between 1966 and 1974, that is seen to have been responsible for the main fallout of short-lived fission products in the southern hemisphere. In contrast to this, the programs of atmospheric nuclear testing in the northern hemisphere up to 1962 are shown to have been the main source of long-lived fission products in fallout in the southern hemisphere. The course followed by this contamination through the environment of the southern hemisphere is traced for the national programs of nuclear testing after 1962 taken separately (France, China) and for the earlier national programs taken together (U.S.S.R., U.S.A. and U.K.). The impact on populations in the southern hemisphere of fallout from atmospheric nuclear weapons tests to date is assessed

  4. Local fall-out and the animal food chain

    International Nuclear Information System (INIS)

    Prat, G.; Mercier, F.J.

    1967-01-01

    The local consequences of fresh fall-out, especially in the case of atmospheric nuclear explosions, are reviewed from the point of view of the internal contamination of the consumer of foodstuffs of animal origin. The edibility of foodstuffs derived from animals having grazed in the presence of fall-out is evaluated both from the wholesome and radio-toxicological points of view. The contamination level of these foodstuffs is calculated as a function of the ground fall-out, and of agronomical and ecological parameters for each radio-nuclide of the animal food chain. The internal exposure of the human consumer is calculated from this level as a function of the diet and of various parameters especially temporal. The equivalent dose to each critical organ, including the digestive tract is deduced from the burdens of each organ. From this a nutritional hygiene in the areas affected by fall-out is obtained, in relationship to the action levels fixed by the responsible authorities in exceptional circumstances. Criteria for these action levels are given as function of the food rations. (authors) [fr

  5. Radioactive fallout in the southern hemisphere from nuclear weapons tests

    International Nuclear Information System (INIS)

    Moroney, J.R.

    1979-01-01

    Fallout in the southern hemisphere, and its origins in the national programs of atmospheric nuclear weapons testing in both hemispheres, are reviewed. Of the 390 nuclear tests conducted in the atmosphere to date, 53 were carried out in the southern hemisphere and it is the second phase of these, between 1966 and 1974, that is seen to have been responsible for the main fallout of short-lived fission products in the southern hemisphere. In contrast to this, the programs of atmospheric nuclear testing in the northern hemisphere up to 1962 are shown to have been the main source of long-lived fission products in fallout in the southern hemisphere. The course followed by this contamination through the environment of the southern hemisphere is traced for the national programs of nuclear testing after 1962 taken separately (France, China) and for the earlier national programs taken together (U.S.S.R., U.S.A. and U.K.). The impact on populations in the southern hemisphere of fallout from atmospheric nuclear weapons tests to date is assessed. (author)

  6. Nuclear Fallout Decision Tool for First Responders

    Energy Technology Data Exchange (ETDEWEB)

    Archibald, E. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Buddemeier, B. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2010-08-11

    If terrorists detonated an improvised nuclear device (IND) in an urban area, thousands of people would die from the blast, and many more would become sick or die from exposure to fallout radiation. Proper sheltering and evacuation can protect people from fallout and save lives. This project provides guidance to first responders as to when to evacuate and what route to take to protect themselves against fallout radiation.

  7. Erosional losses of fallout plutonium

    International Nuclear Information System (INIS)

    Foster, G.R.; Hakonson, T.E.

    1987-01-01

    Plutonium from fallout after atmospheric explosion of nuclear weapons in the 1950's and 1960s is being redistributed over the landscape by soil erosion and carried on sediment by streams to oceans. Erosion rates computed with the Universal Soil Loss Equation for more than 200,000 sample points on nonfederal land across the US were used to estimate plutonium removal rates by soil erosion. On the average, only about 4% of the eroded sediment reaches the outlet of a major river. The remaining sediment is deposited en route, and because deposition is a selective process, the sediment is enriched in fine particles having the highest concentration of plutonium because of the element's strong association with clay and silt-sized sediment. Estimated enrichment ratios, sediment delivery ratios, and erosion rates were used to estimate annual delivery of fallout plutonium. These estimates ranged from 0.002% of the initial fallout plutonium inventory for the Savannah River basin to 0.01% for the Columbia River basin, to 0.02% for the Hudson and Rio Grande River basins, to 0.08% for the Mississippi River basin. If the deposition of plutonium had been uniformly 1 mCi/km 2 , the estimated plutonium activity on suspended sediment would range from about 7 fCi/g of sediment of the Savannah River basin, to 9 fCi/g for the Mississippi River basin, to 12 fCi/g for the Hudson River basin, to 14 fCi/g for the Columbia and Rio Grande River basins. 45 references, 2 figures, 17 tables

  8. Fukushima fallout at Milano, Italy

    International Nuclear Information System (INIS)

    Ioannidou, Alexandra; Manenti, Simone; Luigi Gini,; Groppi, Flavia

    2012-01-01

    The radionuclides 131 I, 137 Cs and 134 Cs were observed in the Milano region (45°) of Italy early after the nuclear accident in Fukushima, Japan. Increased atmospheric radioactivity was observed on an air filter taken on 30 March 2011, while the maximum activity of 467 μBq m −3 for 131 I was recorded at April 3–4, 2011. The first evidence of Fukushima fallout was confirmed with 131 I and 137 Cs measured in precipitation at two sampling sites at Milano on 28 March, 2011, with the concentrations of 131 I and 137 Cs in the rainwater equal to 0.89 Bq L −1 and 0.12 Bq L −1 , respectively. A sample of dry deposition that was collected 9 days after the first rainfall event of 27–28 March, 2011 showed that the dry deposition was more effective in the case of 137 Cs than it was for 131 I, probably because iodine was mainly in gaseous form whereas caesium was rapidly bound to aerosols and thus highly subject to dry deposition. The relatively high observed values of 137 Cs in grass, soil and fresh goat and cow milk samples were probably from Chernobyl fallout and global fallout from past nuclear tests rather than from the Fukushima accident. Finally, a dose assessment for the region of investigation showed clearly that the detected activities in all environmental samples were very far below levels of concern. - Highlights: ► Radioactive plume from Fukushima reactor accident reached Milano, Italy. ► 131 I, 137 Cs and 134 Cs were determined in rainwater, air, soil, grass and milk samples. ► The 134 Cs/ 137 Cs activity ratio values in air was about 1. ► High observed values of 137 Cs in grass, soil and milk samples are not due to Fukushima accident. ► The dose assessment show that the observed activities are very far below levels of concern.

  9. Fallout forecasting: 1945-1962

    International Nuclear Information System (INIS)

    Kennedy, W.R. Jr.

    1986-03-01

    The delayed hazards of fallout from the detonations of nuclear devices in the atmosphere have always been the concern of those involved in the Test Program. Even before the Trinity Shot (TR-2) of July 16, 1945, many very competent, intelligent scientists and others from all fields of expertise tried their hand at the prediction problems. This resume and collection of parts from reports, memoranda, references, etc., endeavor to chronologically outline prediction methods used operationally in the field during Test Operations of nuclear devices fired into the atmosphere

  10. Childhood leukaemia, fallout and radiation doses near Dounreay

    International Nuclear Information System (INIS)

    Darby, S.C.; Doll, Richard

    1987-01-01

    The possible explanations of the recently reported increase in the incidence of childhood leukaemia around Dounreay are examined in the light of the changes in national leukaemia incidence that occurred during the period of exposure to fallout from international atmospheric testing of nuclear weapons. It is concluded that the increase cannot be due to underestimation of the risk of leukaemia per unit dose of radiation, nor to an underestimate of the relative biological efficiency of high as compared with low LET radiation. Possible explanations of the increase include an underestimate of the red bone marrow doses due to the Dounreay discharges relative to those from fallout, a misconception of the site of origin of childhood leukaemia, epidemics of infectious disease and exposure to some other unidentified environmental agent. (author)

  11. Committee's report on ruthenium fall-out incident

    International Nuclear Information System (INIS)

    Borkowski, C.J.; Crawford, J.H.; Livingston, R.; Ritchie, R.H.; Rupp, A.F.; Taylor, E.H.

    1983-07-01

    Investigations of the fall-out incident of November 11 and 12, 1959, by responsible parties (Health Physics Division and Operations Division personnel) established beyond reasonable doubt that the incident had its origin in the expulsion of particles, heavily contaminated with ruthenium, which had been detached from the walls of the electric fan housing and ducts in the off-gas system associated with the brick stack. All available evidence indicates that the particles were loosened during maintenance work on the exhaust damper and the bearings of the electric fan and were carried up the stack in two bursts as particulate fall-out when this fan was put back into service. Radiographic and chemical analysis showed the activity to be almost entirely ruthenium (Ru 106 ) and its daughter rhodium (Rh 106 ) with very little, if any, strontium being present. This report summarizes the findings and sets forth the conclusions and recommendations of the Committee asked to investigate the incident

  12. Automating the Coupling of ORIGEN with GADRAS via the Fallout Analysis Tool for National Technical Nuclear Forensics

    International Nuclear Information System (INIS)

    Monterial, Mateusz; Jodoin, Vincent J.; Lefebvre, Jordan P.; Peplow, Douglas E.; Hooper, David A.

    2012-01-01

    Nuclear forensic teams will be deployed to collect and evaluate fallout samples on the ground in the scenario of a low-yield nuclear detonation in a heavily populated area. Quick non-destructive methods of predicting the quality of the sample before it is analyzed in detail are essential for efficient post-event collections. In this work, the process of exporting Defense Land Fallout Interpretive Code (DELFIC) results into Gamma Detector Response and Analysis Software (GADRAS) has been automated within the Fallout Analysis Tool. This coupling allows for the simulation of detector responses to fallout samples with varying degrees of fractionation. The degree to which the samples are fractionated depends on the location of the samples in the fallout field. In the following study, this phenomenon is examined, as its understanding is important to the investigation of debris distribution. The simulated detector spectra from GADRAS can be used to compare peak ratios of volatile-refractory isotope pairs in order to determine the degree of fractionation. Simulated fractionated fallout samples from DELFIC for a 10 kt, pure 235U fission surface burst were modeled for distances ranging to 256 km out from ground zero, and for times up to 1 week from detonation. The fractionation ratios, also known as r values, from isotope concentrations, photon lines and peak areas of four volatile-refractory pairs were calculated and compared. Fractionation prediction via the peak areas method was evaluated for each pair by comparing the results with the simulated radionuclide inventory.

  13. A fall-out shelter

    International Nuclear Information System (INIS)

    Blatchford, J.M.A.

    1982-01-01

    A strong structure of precast concrete for use as, for example, a fallout shelter, strong-room or electricity sub-station is described. The major portion is generally tubular in construction and rectangular in cross-section. The tube may be formed in one piece or with two directed channel elements. Pairs of U legs abut either along the sides or along the top and bottom. End slabs close the compartment. An entrance shaft is formed by an upstanding channel element with upper and lower end slabs; alternatively the entrance shaft may be horizontal. Doors or hatches are provided. The whole structure may be buried. This invention provides a structure capable of withstanding considerable overpressure and of offering good resistance to radiation and is cheap and simple to manufacture. (U.K.)

  14. Meteorological modeling of arrival and deposition of fallout at intermediate distances downwind of the Nevada Test Site

    International Nuclear Information System (INIS)

    Cederwall, R.T.; Peterson, K.R.

    1990-01-01

    A three-dimensional atmospheric transport and diffusion model is used to calculate the arrival and deposition of fallout from 13 selected nuclear tests at the Nevada Test Site (NTS) in the 1950s. Results are used to extend NTS fallout patterns to intermediate downwind distances (300 to 1200 km). The radioactive cloud is represented in the model by a population of Lagrangian marker particles, with concentrations calculated on an Eulerian grid. Use of marker particles, with fall velocities dependent on particle size, provides a realistic simulation of fallout as the debris cloud travels downwind. The three-dimensional wind field is derived from observed data, adjusted for mass consistency. Terrain is represented in the grid, which extends up to 1200 km downwind of NTS and has 32-km horizontal resolution and 1-km vertical resolution. Ground deposition is calculated by a deposition-velocity approach. Source terms and relationships between deposition and exposure rate are based on work by Hicks. Uncertainty in particle size and vertical distributions within the debris cloud (and stem) allow for some model tuning to better match measured ground-deposition values. Particle trajectories representing different sizes and starting heights above ground zero are used to guide source specification. An hourly time history of the modeled fallout pattern as the debris cloud moves downwind provides estimates of fallout arrival times. Results for event HARRY illustrate the methodology. The composite deposition pattern for all 13 tests is characterized by two lobes extending out to the north-northeast and east-northeast, respectively, at intermediate distances from NTS. Arrival estimates, along with modeled deposition values, augment measured deposition data in the development of data bases at the county level

  15. Radioactive fallout and neural tube defects

    Directory of Open Access Journals (Sweden)

    Nejat Akar

    2015-10-01

    Full Text Available Possible link between radioactivity and the occurrence of neural tube defects is a long lasting debate since the Chernobyl nuclear fallout in 1986. A recent report on the incidence of neural defects in the west coast of USA, following Fukushima disaster, brought another evidence for effect of radioactive fallout on the occurrence of NTD’s. Here a literature review was performed focusing on this special subject.

  16. Radioactivity monitoring of fallout, water and ground

    International Nuclear Information System (INIS)

    Radosavljevic, R.

    1961-01-01

    During 1961, the radioactivity monitoring of the Boris Kidric Institute site covered monitoring of the total β activity of the fallout and water on the site. Activity of the fallout was monitored by measuring the activity of the rain and collected sedimented dust form the atmosphere. Water monitored was the water from Danube and river Mlaka, technical and drinking water. Plants and soil activity were not measured although sample were taken and the total β activity will be measured and analysed later

  17. Magnitude-frequency characteristics and preparatory factors for spatial debris-slide distribution in the northern Faroe Islands

    DEFF Research Database (Denmark)

    Dahl, Mads-Peter Jakob; Jensen, Niels H.; Veihe, Anita

    2013-01-01

    The Faroe Islands in the North Atlantic Ocean are highly susceptible to debris-avalanches and debris-flows originating from debris-slide activity in shallow colluvial soils. To provide data for hazard and risk assessment of debris-avalanches and debris-flows, this study aims at quantifying the ma...

  18. Building Protection Against External Ionizing Fallout Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, Michael B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Homann, Steven G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-12-01

    A nuclear explosion has the potential to injure or kill tens to hundreds of thousands of people through exposure to fallout (external gamma) radiation. Existing buildings can protect their occupants (reducing external radiation exposures) by placing material and distance between fallout particles and indoor individuals. This protection is not well captured in current fallout risk assessment models and so the US Department of Defense is implementing the Regional Shelter Analysis methodology to improve the ability of the Hazard Prediction and Assessment Capability (HPAC) model to account for building protection. This report supports the HPAC improvement effort by identifying a set of building attributes (next page) that, when collectively specified, are sufficient to calculate reasonably accurate, i.e., within a factor of 2, fallout shelter quality estimates for many individual buildings. The set of building attributes were determined by first identifying the key physics controlling building protection from fallout radiation and then assessing which building attributes are relevant to the identified physics. This approach was evaluated by developing a screening model (PFscreen) based on the identified physics and comparing the screening model results against the set of existing independent experimental, theoretical, and modeled building protection estimates. In the interests of transparency, we have developed a benchmark dataset containing (a) most of the relevant primary experimental data published by prior generations of fallout protection scientists as well as (b) the screening model results.

  19. Manual estimation of fallout casualties. Final report

    International Nuclear Information System (INIS)

    Gant, K.S.; Haaland, C.M.

    1978-08-01

    A method is described for enabling Emergency Operating Centers (EOCs) to estimate nuclear fallout casualties (fatalities and injuries) during and after nuclear attack without the aid of computers. This method is compatible with the current manual method for estimating initial weapons effects. The new technique requires that the EOCs have information on nuclear detonations and upper wind conditions and that they have maps, a protractor, map overlay material, grease pencils, worksheets, and pencils. In addition, they will need two tables of data and a fallout casualty (FC) template, all supplied in this report. Five steps are involved in the estimation of fallout casualties for an area: sketching fallout wind streamlines on a map overlay; plotting locations of nuclear detonations and their fallout streamlines; measuring crosswind and upwind distances to detonation points from the point of interest; reading radiation exposure tables and summing the contributions from different weapons to obtain the exposure at that point; and using the FC template with the protection factor profile for the area to estimate fatalities and injuries. The tables of radiation exposure are based on a modified Weapons Systems Evaluation Group-10 (WSEG-10) fallout model. The table of county protection factor profiles (PFPs) assumes a Community Shelter Plan (CSP) posture

  20. The physics of debris flows

    Science.gov (United States)

    Iverson, Richard M.

    1997-08-01

    permeability of the debris. Realistic models of debris flows therefore require equations that simulate inertial motion of surges in which high-resistance fronts dominated by solid forces impede the motion of low-resistance tails more strongly influenced by fluid forces. Furthermore, because debris flows characteristically originate as nearly rigid sediment masses, transform at least partly to liquefied flows, and then transform again to nearly rigid deposits, acceptable models must simulate an evolution of material behavior without invoking preternatural changes in material properties. A simple model that satisfies most of these criteria uses depth-averaged equations of motion patterned after those of the Savage-Hutter theory for gravity-driven flow of dry granular masses but generalized to include the effects of viscous pore fluid with varying pressure. These equations can describe a spectrum of debris flow behaviors intermediate between those of wet rock avalanches and sediment-laden water floods. With appropriate pore pressure distributions the equations yield numerical solutions that successfully predict unsteady, nonuniform motion of experimental debris flows.

  1. The physics of debris flows

    Science.gov (United States)

    Iverson, R.M.

    1997-01-01

    permeability of the debris. Realistic models of debris flows therefore require equations that simulate inertial motion of surges in which high-resistance fronts dominated by solid forces impede the motion of low-resistance tails more strongly influenced by fluid forces. Furthermore, because debris flows characteristically originate as nearly rigid sediment masses, transform at least partly to liquefied flows, and then transform again to nearly rigid deposits, acceptable models must simulate an evolution of material behavior without invoking preternatural changes in material properties. A simple model that satisfies most of these criteria uses depth-averaged equations of motion patterned after those of the Savage-Hutter theory for gravity-driven flow of dry granular masses but generalized to include the effects of viscous pore fluid with varying pressure. These equations can describe a spectrum of debris flow behaviors intermediate between those of wet rock avalanches and sediment-laden water floods. With appropriate pore pressure distributions the equations yield numerical solutions that successfully predict unsteady, nonuniform motion of experimental debris flows.

  2. Origin,

    Directory of Open Access Journals (Sweden)

    Artur de Vargas Giorgi

    2011-02-01

    Full Text Available This essay tightens the “origin” concept, its manifestation through puzzles and their relationship to techniques of reproduction. Contrary to the hegemonic critique of aesthetic and cultural objects – critique that, settled on the appearance and notions of identity, tradition, canon, etc., undervalues the reproductions of "originals" –, the aim is to deliver these objects from formal hierarchization dispositives, that is, release them of what is ideal and positively imposed, so that the reproducibility is potentiated as producer of singularities, of apparitions. The effort is to keep the undecided character of puzzles (bodies, texts, images in which the origin is manifest, so that the logic of the spectacle is reverted into sense opening, instance in which the aesthetic becomes a “performance” before contemporary complexity. With the reproducibility, an origin survives in passage: continually restored, but incomplete, present in trace, in absence.

  3. Characteristics, extent and origin of hydrothermal alteration at Mount Rainier Volcano, Cascades Arc, USA: Implications for debris-flow hazards and mineral deposits

    Science.gov (United States)

    John, D.A.; Sisson, T.W.; Breit, G.N.; Rye, R.O.; Vallance, J.W.

    2008-01-01

    Hydrothermal alteration at Mount Rainier waxed and waned over the 500,000-year episodic growth of the edifice. Hydrothermal minerals and their stable-isotope compositions in samples collected from outcrop and as clasts from Holocene debris-flow deposits identify three distinct hypogene argillic/advanced argillic hydrothermal environments: magmatic-hydrothermal, steam-heated, and magmatic steam (fumarolic), with minor superimposed supergene alteration. The 3.8??km3 Osceola Mudflow (5600??y BP) and coeval phreatomagmatic F tephra contain the highest temperature and most deeply formed hydrothermal minerals. Relatively deeply formed magmatic-hydrothermal alteration minerals and associations in clasts include quartz (residual silica), quartz-alunite, quartz-topaz, quartz-pyrophyllite, quartz-dickite/kaolinite, and quartz-illite (all with pyrite). Clasts of smectite-pyrite and steam-heated opal-alunite-kaolinite are also common in the Osceola Mudflow. In contrast, the Paradise lahar, formed by collapse of the summit or near-summit of the edifice at about the same time, contains only smectite-pyrite and near-surface steam-heated and fumarolic alteration minerals. Younger debris-flow deposits on the west side of the volcano (Round Pass and distal Electron Mudflows) contain only low-temperature smectite-pyrite assemblages, whereas the proximal Electron Mudflow and a formed at higher temperatures. The pre-Osceola Mudflow alteration geometry is inferred to have consisted of a narrow feeder zone of intense magmatic-hydrothermal alteration limited to near the conduit of the volcano, which graded outward to more widely distributed, but weak, smectite-pyrite alteration within 1??km of the edifice axis, developed chiefly in porous breccias. The edifice was capped by a steam-heated alteration zone, most of which resulted from condensation of fumarolic vapor and oxidation of H2S in the unsaturated zone above the water table. Weakly developed smectite-pyrite alteration extended into

  4. Orbital debris: a technical assessment

    National Research Council Canada - National Science Library

    Committee on Space Debris, National Research Council

    ..., and other debris created as a byproduct of space operations. Orbital Debris examines the methods we can use to characterize orbital debris, estimates the magnitude of the debris population, and assesses the hazard that this population poses to spacecraft...

  5. The effects of fallout from nuclear explosions

    International Nuclear Information System (INIS)

    Cook, J.

    1987-01-01

    Early fallout from surface or near surface nuclear explosions leads to radiation doses at levels sufficient to cause deaths from the acute effects of radiation over large areas, particularly if no means of avoiding exposure are available. For example, early fallout from a 10 megatonne weapon could lead to doses in excess of 4 or 5 grays (at which half of those exposed die) over an area of about 25,000 square kilometres, in a deposit perhaps 400 km long and 80 km wide. The survivors of early fallout are likely to experience a significant increase in thyroid disease (for children at the time of exposure), in leukaemia and a probably detectable increase in cancer. It is unlikely that there would be any significant increase in the incidence of genetic disability and ill-health in the children of the survivors. Delayed fallout would be distributed fairly uniformly around the earth. The additional cancer and genetic risks from delayed fallout are small, the cancer risk being less than 1 per cent of natural incidence and the genetic risk being undetectable

  6. Lichens of the alps as biomonitors for radioactive fallout

    International Nuclear Information System (INIS)

    Hofmann, W.; Gastberger, M.; Tuerk, R.

    1995-07-01

    A number of surveys has shown, that shortly after a radioactive fallout lichens are highly contaminated and their contamination correlates well with the soil deposition data. One of the major advantages of lichens is that samples can be collected from quite large areas, thereby getting an average contamination of this area. Especially in mountain ecosystems, lichens could gain great importance as biomonitors, because many lichens grow in this area. Moreover, the collection of soil samples can be very difficult. For this survey soil and lichen samples were collected from a mountain called Stubnerkogel, which is located in the south of the province of Salzburg. The samples were taken in the summer of 1993, that means more than 7 years after the nuclear accident in Chernobyl. The aim of this study was to find out, if some years after a nuclear fallout has occurred lichens are still suitable biological detectors of the radioactive contamination. The lichen samples had 137 Cs activities between 400 and 5.000 Bq per kg dry weight. Even for small samples these comparatively high activities are easy to measure, because of their long life expectancy lichens can be used as biomonitors for a radioactive contamination which happened a few years ago. One sampling site allowed the collection of different lichen species in a very restricted area. It was possible to find specific differences in the 137 Cs contamination between the various species; Cetraria islandica, Cladonia arbuscula and Cladonia rangiferina had the highest contamination levels. These three species are very common in alpine regions, so they prove to be especially suitable biomonitors of radioactive fallout. Furthermore it was partly possible to find small amounts of 137 Cs in the soil, which originate from nuclear weapons tests (this was impossible for any of the lichen samples). Thus lichens can be very useful when a fallout which occurred shortly ago should be separated from a fallout which had occurred a long

  7. Radiation doses in Sweden as a result of the Chernobyl fallout

    Energy Technology Data Exchange (ETDEWEB)

    Wiktorson, Christor [Statens Stralskyddsinstitut, National Institute of Radiation Protection, Stockholm (Sweden)

    1986-07-01

    The radiation doses from the Chernobyl fallout originate mainly from two sources: External irradiation (ground radiation) and internal irradiation from radioactive materials accumulated in the human body via food. In addition there are an inhalation dose and a radiation dose from the radioactive cloud. The level of doses from the various sources is presented.

  8. Radiation doses in Sweden as a result of the Chernobyl fallout

    International Nuclear Information System (INIS)

    Wiktorson, Christor

    1986-01-01

    The radiation doses from the Chernobyl fallout originate mainly from two sources: External irradiation (ground radiation) and internal irradiation from radioactive materials accumulated in the human body via food. In addition there are an inhalation dose and a radiation dose from the radioactive cloud. The level of doses from the various sources is presented

  9. Fallout, radiation doses near Dounreay, and childhood leukaemia

    International Nuclear Information System (INIS)

    Darby, S.C.; Doll, Richard

    1987-01-01

    Possible explanations for the recently reported increased incidence of childhood leukaemia around Dounreay were examined in the light of changes in the national incidence of leukaemia that occurred during the period of exposure to fallout from international testing of nuclear weapons in the atmosphere. It was concluded that the increase could not be accounted for by underestimate of the risk of leukaemia per unit dose of radiation at low doses and low dose rates, nor by underestimate of the relative biological efficiency of high compared with low linear energy transfer radiation. One possible explanation was underestimation of doses to the red bone marrow due to the discharges at Dounreay relative to dose from fallout, though investigation of ways in which this might have occurred did not suggest anything definite. Other explanations included a misconception of the site of origin of childhood leukaemia, outbreaks of an infectious disease and exposure to other, unidentified environmental agents. These findings weigh against the hypothesis that the recent increase in childhood leukaemia near Dounreay might be accounted for by radioactive discharges from nuclear plants, unless the doses to the stem cells from which childhood leukaemia originates have been grossly underestimated. (author)

  10. Characteristics, extent and origin of hydrothermal alteration at Mount Rainier Volcano, Cascades Arc, USA: Implications for debris-flow hazards and mineral deposits

    Science.gov (United States)

    John, David A.; Sisson, Thomas W.; Breit, George N.; Rye, Robert O.; Vallance, James W.

    2008-08-01

    Hydrothermal alteration at Mount Rainier waxed and waned over the 500,000-year episodic growth of the edifice. Hydrothermal minerals and their stable-isotope compositions in samples collected from outcrop and as clasts from Holocene debris-flow deposits identify three distinct hypogene argillic/advanced argillic hydrothermal environments: magmatic-hydrothermal, steam-heated, and magmatic steam (fumarolic), with minor superimposed supergene alteration. The 3.8 km 3 Osceola Mudflow (5600 y BP) and coeval phreatomagmatic F tephra contain the highest temperature and most deeply formed hydrothermal minerals. Relatively deeply formed magmatic-hydrothermal alteration minerals and associations in clasts include quartz (residual silica), quartz-alunite, quartz-topaz, quartz-pyrophyllite, quartz-dickite/kaolinite, and quartz-illite (all with pyrite). Clasts of smectite-pyrite and steam-heated opal-alunite-kaolinite are also common in the Osceola Mudflow. In contrast, the Paradise lahar, formed by collapse of the summit or near-summit of the edifice at about the same time, contains only smectite-pyrite and near-surface steam-heated and fumarolic alteration minerals. Younger debris-flow deposits on the west side of the volcano (Round Pass and distal Electron Mudflows) contain only low-temperature smectite-pyrite assemblages, whereas the proximal Electron Mudflow and a < 100 y BP rock avalanche on Tahoma Glacier also contain magmatic-hydrothermal alteration minerals that are exposed in the avalanche headwall of Sunset Amphitheater, reflecting progressive incision into deeper near-conduit alteration products that formed at higher temperatures. The pre-Osceola Mudflow alteration geometry is inferred to have consisted of a narrow feeder zone of intense magmatic-hydrothermal alteration limited to near the conduit of the volcano, which graded outward to more widely distributed, but weak, smectite-pyrite alteration within 1 km of the edifice axis, developed chiefly in porous breccias

  11. Reconstruction and analysis of cesium-137 fallout deposition patterns in the Marshall Islands

    Science.gov (United States)

    Whitcomb, Robert Cleckley, Jr.

    Estimates of 137Cs deposition due to fallout originating from nuclear weapons testing in the Marshall Islands have been made for several locations in the Marshall Islands. These retrospective estimates were based primarily on historical exposure rate and gummed film measurements. The methods used to reconstruct these deposition estimates are specific for six of the Pacific tests. These methods are also similar to those used in the National Cancer Institute study for reconstructing 131I deposition from the Nevada Test Site. Reconstructed cumulative deposition estimates are validated against contemporary measurements of 137Cs concentration in soil. This validation work also includes an accounting for estimated global fallout contributions. These validations show that the overall geometric bias in predicted-to-observed (P/O) ratios is 1.0 (indicating excellent agreement). The 5th and 95th percentile range of this distribution is 0.35--2.95. The P/O ratios for estimates using historical gummed film measurements tend to slightly over-predict more than estimates using exposure rate measurements. The methods produce reasonable estimates of deposition confirming that radioactive fallout occurred at atolls further south of the four northern atolls recognized by the Department of Energy as being affected by fallout. The deposition estimate methods, supported by the very good agreement between estimates and measurements, suggest that these methods can be used for other weapons testing fallout radionuclides with confidence.

  12. Radioecological sensitivity. Danish fallout data revisited

    International Nuclear Information System (INIS)

    Nielsen, S.P.; Oehlenschlaeger, M.

    1999-01-01

    Danish fallout data covering four decades are interpreted in terms of radioecological sensitivity. The radioecological sensitivity is the time-integrated radionuclide concentration in an environmental sample from a unit ground deposition (e.g. Bq y kg -1 per Gq m -2 ). The fallout data comprise observed levels of the radionuclides 137 Cs and 90 Sr in precipitation, grass, milk, beef and diet. The data are analysed with different types of radioecological models: traditional UNSCEAR models and more recent dynamic models. The traditional models provide empirical relationships between the annual fallout from precipitation and the annual average levels in grass, milk, beef and diet. The relationships may be derived from spreadsheet calculations. ECOSYS and FARMLAND represent more recent radioecological models, which are available as software for personal computers. These models are more mechanistic and require information on a range of topics, e.g. mode of deposition, nuclide dependent and nuclide independent parameters. The more recent models do not reproduce the fallout data better than the traditional models. But the general features of the more recent models make them suited for prediction of radiological consequences of routine and accidental releases in areas where limited radioecological data are available. The work is part of the NKS/BOK-2.1 project on Important Nordic Food Chains aiming at characterising radioecological sensitivity and variability across the Nordic countries. (au)

  13. Temporary/portable nuclear fallout shelter

    Energy Technology Data Exchange (ETDEWEB)

    Hampel, V E

    1991-01-15

    The design and invention of a temporary/portable fallout shelter has been described in context of schematic and representative embodiments. Tent structures are described which include disposable, exterior, semi-transparent plastic and/or fabric shield membranes covering a tent composed of stretched, tightly woven, rip-resistant fabric panels supported by tensile rods/wands. 16 figs.

  14. Tracking the origins of plastic debris across the Coral Sea: A case study from the Ouvéa Island, New Caledonia.

    Science.gov (United States)

    Maes, Christophe; Blanke, Bruno

    2015-08-15

    Contamination of the marine environment by human-made plastic litter is a growing and global problem. Our study attempts to explain the presence of two plastic bottles beached on the Ouvéa Island, in the southwest Pacific Ocean, with trademarks from the Solomon Islands and Papua New Guinea (PNG). We simulate the oceanic drift tracks and associated transit times with a Lagrangian interpretation of the surface currents of a high-resolution ocean model. Our results show that it takes less than 2-3months for drifting objects to connect these archipelagos (New Caledonia, Solomon Islands and PNG) and highlight the role of the meridional component of the circulation rather than the dominant zonal jets. This study shows that the origin or traceability of trash represent valuable information that can be used to test and, ultimately, improve our understanding of ocean circulation. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Carborne fallout mapping - STUK/HUT team

    Energy Technology Data Exchange (ETDEWEB)

    Honkamaa, T.; Tiilikainen, H. [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland); Aarnio, P.; Nikkinen, M. [Helsinki Univ. of Technology, Espoo (Finland)

    1997-12-31

    During the summer 1995 altogether 8,625 spectrometric and 3,108 dose-rate measurements were performed in Padasjoki Auttoinen village using carborne measuring devices. As a result {sup 137}Cs fallout and dose-rate maps were produced. The highest measured values in the test area II were 160 kBq m{sup -2} for fallout and 0.22 {mu}Sv h{sup -1} for dose-rate. One hot spot was found beside the test area (dose rate 0.31 {mu}Sv h{sup -1}). On the cultivated areas the measured count rates in {sup 137}Cs-window are three to four times lower than in the forest areas in average, indicating an altered depth profile of caesium. (au).

  16. FALLOUT RADIATION: EFFECTS ON THE SKIN

    Energy Technology Data Exchange (ETDEWEB)

    Conard, R. A.; Cronkite, E. P.; Bond, V. P.

    1963-02-06

    Until recently it has been generally assumed that injury to the skin from ionizing radiation was not a serious hazard associated with the detonation of nuclear dcvices. However, in 1954 the importance of this hazard became apparent when widespread lesions of the skin developed in a large group of people accidentally exposed to fallout radiation in the Marshall Islands following the experimental detonation of a large nuclear device. The accident in the Marshall Islands affords an example of large numbers of lesions of the skin in human beings from the fallout. Studies have been documented and will be referred to frequently in this chapter. The possibility of such accidents must be considered seriously in view of the increasingly widespread use of radioisotopes.

  17. Carborne fallout mapping - STUK/HUT team

    International Nuclear Information System (INIS)

    Honkamaa, T.; Tiilikainen, H.; Aarnio, P.; Nikkinen, M.

    1997-01-01

    During the summer 1995 altogether 8,625 spectrometric and 3,108 dose-rate measurements were performed in Padasjoki Auttoinen village using carborne measuring devices. As a result 137 Cs fallout and dose-rate maps were produced. The highest measured values in the test area II were 160 kBq m -2 for fallout and 0.22 μSv h -1 for dose-rate. One hot spot was found beside the test area (dose rate 0.31 μSv h -1 ). On the cultivated areas the measured count rates in 137 Cs-window are three to four times lower than in the forest areas in average, indicating an altered depth profile of caesium. (au)

  18. Modeling Fallout of Anthropogenic I-129

    DEFF Research Database (Denmark)

    Englund, Edvard; Aldahan, Als; Possnert, Göran

    2008-01-01

    Despite the relatively well-recognized emission rates of the anthropogenic 1291, there is little knowledge about the temporal fallout patterns and magnitude of fluxes since the start of the atomic era at the early 1940s. We here present measurements of annual 1291 concentrations in sediment......, a numerical model approach was used taking into account the emission rates/estimated fallout, transport pathways, and the sediment system. The model outcomes suggest a relatively dominating marine source of 1291 to north Europe compared to direct gaseous releases. A transfer rate of 1291 from sea...... to atmosphere is derived for pertinent sea areas (English Channel, Irish Sea, and North Sea), which is estimated at 0.04 to 0.21 y(-1)....

  19. Carborne fallout mapping - STUK/HUT team

    Energy Technology Data Exchange (ETDEWEB)

    Honkamaa, T; Tiilikainen, H [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland); Aarnio, P; Nikkinen, M [Helsinki Univ. of Technology, Espoo (Finland)

    1998-12-31

    During the summer 1995 altogether 8,625 spectrometric and 3,108 dose-rate measurements were performed in Padasjoki Auttoinen village using carborne measuring devices. As a result {sup 137}Cs fallout and dose-rate maps were produced. The highest measured values in the test area II were 160 kBq m{sup -2} for fallout and 0.22 {mu}Sv h{sup -1} for dose-rate. One hot spot was found beside the test area (dose rate 0.31 {mu}Sv h{sup -1}). On the cultivated areas the measured count rates in {sup 137}Cs-window are three to four times lower than in the forest areas in average, indicating an altered depth profile of caesium. (au).

  20. Radioactive fallout in Norway in 1964

    International Nuclear Information System (INIS)

    Oftedal, P.

    1989-01-01

    Scholastic achievement of Norwegian children born in 1965 has been analysed in relation to date of birth and school address, in order to examine a possible effect of radioactive fallout during their fetal period. The Western regions of the country had an order of magnitude higher fallout contamination than the Eastern region. There was in the Western region a pronounced seasonal variation in e.g. 137 Cs content of milk. The results indicate a deficiency in scholastic achievement in the West cohort corresponding to the coincidence of the most sensitive fetal period (8-15 weeks post conception) with the 1964 late summer increase in 137 Cs content of milk. The dose from fallout is several orders of magnitude too low to explain the observed deficiency quantitatively in consonance with the Hiroshima-Nagasaki findings. It is suggested that the explaination may be found be way of a repair induction lag hypothesis, related to the microdosimetric conditions at background dose rate level. (author)

  1. Debris thickness patterns on debris-covered glaciers

    Science.gov (United States)

    Anderson, Leif S.; Anderson, Robert S.

    2018-06-01

    Many debris-covered glaciers have broadly similar debris thickness patterns: surface debris thickens and tends to transition from convex- to concave-up-down glacier. We explain this pattern using theory (analytical and numerical models) paired with empirical observations. Down glacier debris thickening results from the conveyor-belt-like nature of the glacier surface in the ablation zone (debris can typically only be added but not removed) and from the inevitable decline in ice surface velocity toward the terminus. Down-glacier thickening of debris leads to the reduction of sub-debris melt and debris emergence toward the terminus. Convex-up debris thickness patterns occur near the up-glacier end of debris covers where debris emergence dominates (ablation controlled). Concave-up debris thickness patterns occur toward glacier termini where declining surface velocities dominate (velocity controlled). A convex-concave debris thickness profile inevitably results from the transition between ablation-control and velocity-control down-glacier. Debris thickness patterns deviating from this longitudinal shape are most likely caused by changes in hillslope debris supply through time. By establishing this expected debris thickness pattern, the effects of climate change on debris cover can be better identified.

  2. Individual external exposures from Nevada Test Site fallout for Utah leukemia cases and controls

    International Nuclear Information System (INIS)

    Lloyd, R.D.; Gren, D.C.; Simon, S.L.; Wrenn, M.E.; Hawthorne, H.A.; Lotz, T.M.; Stevens, W.; Till, J.E.

    1990-01-01

    External gamma-ray exposures from fallout originating at the Nevada Test Site (NTS) have been assigned to 6,507 individual subjects (1,177 leukemia cases and 5,330 control subjects) who died as Utah residents between 1952 and 1981. Leukemia cases were identified, confirmed, and classified by cell type from the Utah Cancer Registry, Utah State vital records, and medical records. Residential histories were obtained from the Deceased Membership File (DMF) of the Church of Jesus Christ of Latter-day Saints (LDS), supplemented by information from the LDS Church Census Records that were taken in 1950, 1955, and 1960-62. Control subjects were selected randomly within age strata from the DMF and were frequency-matched to the cases by age at death and for sex. Individual radiation exposures were assigned as a function of residence location and time interval for each residence during the fallout period (1951-1958) using geographic exposure data taken from the literature. Temporal distribution of exposure for subjects who resided in more than one locality or who were born or died during the fallout period was determined from data of other investigators. Calculated gamma-ray exposures for each place of residence were summed for each subject to yield the exposure to fallout from the NTS

  3. Tracking the debris cloud from a Chinese nuclear test

    International Nuclear Information System (INIS)

    Peterson, K.R.

    1977-01-01

    As the radioactive debris cloud from a Chinese nuclear test on September 26, 1976 began drifting eastward, the Laboratory's computational facilities were pressed into service to predict the possible environmental effects. ERDA asked us to calculate cloud trajectories and to estimate the fallout dose. The FAA asked us to provide dose estimates both for commercial aircraft flights within the U.S. and for transatlantic flights of the Concorde SST. Our dose estimates, calculated with 2BPUFF, a large-cloud diffusion code, proved to be accurate predictions, correlating well with later observations. At FAA and ERDA request, we also worked with EG and G to measure cabin dose rates in some transatlantic SST and subsonic flights while the debris cloud moved out over the Atlantic Ocean

  4. Measurement of strontium 90 in the rain fall-out

    International Nuclear Information System (INIS)

    Suratman; Soedyartomo; Suhartono.

    1976-01-01

    The procedure of radioactivity measurement of strontium 90 in the rain fallout as well as the measurement of the fallout gross beta activity have been studied. In the preliminary study strontium 90 is separated from other cations especially fission products by fuming nitric acid, and radioactivity measurement is carried out in the form of strontium oxalate. Data of radioactivity measurement of strontium 90 and the gross beta activity in the fallout are given. (author)

  5. Radioactive fallout collected in Tokyo on November 26, 1955

    Energy Technology Data Exchange (ETDEWEB)

    Sugiura, Y; Kanazawa, T

    1956-01-01

    A large nuclear weapon test by Russia was reported November 23, 1955 as having occurred the previous day. Rain water and fallout samples taken in Tokyo before and after the 22nd indicated the test had produced a secondary fallout from some previous explosion. Rain water of the 21st and fallout of the 29th had radioactive content of 13 days half-life; fallout of the 26th, rain of the 27th 3 days half-life. Sample of the 26th consisted of 15 mg of sooty material giving nearly 2000 counts/min at that time.

  6. The KFM, A Homemade Yet Accurate and Dependable Fallout Meter

    Energy Technology Data Exchange (ETDEWEB)

    Kearny, C.H.

    2001-11-20

    The KFM is a homemade fallout meter that can be made using only materials, tools, and skills found in millions of American homes. It is an accurate and dependable electroscope-capacitor. The KFM, in conjunction with its attached table and a watch, is designed for use as a rate meter. Its attached table relates observed differences in the separations of its two leaves (before and after exposures at the listed time intervals) to the dose rates during exposures of these time intervals. In this manner dose rates from 30 mR/hr up to 43 R/hr can be determined with an accuracy of {+-}25%. A KFM can be charged with any one of the three expedient electrostatic charging devices described. Due to the use of anhydrite (made by heating gypsum from wallboard) inside a KFM and the expedient ''dry-bucket'' in which it can be charged when the air is very humid, this instrument always can be charged and used to obtain accurate measurements of gamma radiation no matter how high the relative humidity. The heart of this report is the step-by-step illustrated instructions for making and using a KFM. These instructions have been improved after each successive field test. The majority of the untrained test families, adequately motivated by cash bonuses offered for success and guided only by these written instructions, have succeeded in making and using a KFM. NOTE: ''The KFM, A Homemade Yet Accurate and Dependable Fallout Meter'', was published by Oak Ridge National Laboratory report in1979. Some of the materials originally suggested for suspending the leaves of the Kearny Fallout Meter (KFM) are no longer available. Because of changes in the manufacturing process, other materials (e.g., sewing thread, unwaxed dental floss) may not have the insulating capability to work properly. Oak Ridge National Laboratory has not tested any of the suggestions provided in the preface of the report, but they have been used by other groups. When using these

  7. Evaluation of 7Be fallout spatial variability

    International Nuclear Information System (INIS)

    Pinto, Victor Meriguetti

    2011-01-01

    The cosmogenic radionuclide beryllium-7 (Be) is produced in the atmosphere by cosmic particle reactions and is being used as a tracer for soil erosion and climatic processes research. After the production, 7 Be bonds to aerosol particles in the atmosphere and is deposited on the soil surface with other radionuclide species by rainfall. Because of the high adsorption on soil particles and its short half-life of 53.2 days, this radionuclide follows of the erosion process and can be used as a tracer to evaluate the sediment transport that occurs during a single rain event or short period of rain events. A key assumption for the erosion evaluation through this radiotracer is the uniformity of the spatial distribution of the 7 Be fallout. The 7 Be method was elaborated recently and due to its few applications, some assumptions related to the method were not yet properly investigated yet, and the hypothesis of 7 Be fallout uniformity needs to be evaluated. The aim of this study was to evaluate the 7 Be fallout spatial distribution through the rain water 7 Be activity analysis of the first five millimeters of single rain events. The rain water was sampled using twelve collectors distributed on an experimental area of about 300 m2 , located in the campus of Sao Paulo University, Piracicaba. The 7 Be activities were measured using a 53% efficiency gamma-ray spectrometer from the Radioisotope laboratory of CENA. The 7 Be activities in rain water varied from 0.26 to 1.81 Sq.L - 1, with the highest values in summer and lowest in spring. In each one of the 5 single events, the spatial variability of 7 Se activity in rain water was high, showing the high randomness of the fallout spatial distribution. A simulation using the 7 Be spatial variability values obtained here and 7 Se average reference inventories taken from the literature was performed determining the lowest detectable erosion rate estimated by 7 Be model. The importance of taking a representative number of samples to

  8. Radioactive fallout has different effects in Lapland

    International Nuclear Information System (INIS)

    Rissanen, K.

    1993-01-01

    The effects of radioactive fallout in Lapland differ from those in southern Finland. The subarctic area is poor in vegetation and nutrients, for which reason radioactive substances enter food chains rapidly. As potassium is low in supply in the north, plants use cesium to replace it. Thus cesium is accumulated very effectively in food chain. When in the food chain, cesium is enriched in reindeer and further in Lapp people, who eat reindeer meat frequently. The Finnish Centre for Radiation and Nuclear Safety established a regional laboratory in northern Finland in the 1970's to monitor radiation and carry out research an the area.(author)

  9. Predicted erosion and sediment delivery of fallout plutonium

    International Nuclear Information System (INIS)

    Foster, G.R.; Hakonson, T.E.

    1984-01-01

    Plutonium (Pu) from fallout after atmospheric explosion of nuclear weapons in the 1950s and 1960s is being redistributed over the landscape by soil erosion and carried on sediment by streams to oceans. Erosion rates computed with the Universal Soil Loss Equation for about 200,000 sample points on nonfederal land across the US were used to estimate Pu removal rates by soil erosion by water, Pu delivery in several major rivers, and concentration of Pu on the transported sediment. Estimates of average annual Pu delivery on sediment ranged from 0.002% of the initial fallout Pu inventory for the Savannah River basin to 0.08% for the Mississippi River basin. If the deposition of Pu had been uniformly 37 Bq/m 2 , the estimated Pu activity on suspended sediment ranged from about 0.26 Bq/kg of sediment for the Savannah River basin to 0.52 Bq/kg for the Columbia and Rio Grande river basins. After 1000 yr, about 9 to 48% of the initial Pu inventory will remain in US soils that are eroding. Much of the Pu on eroded sediment will travel only a short distance from its origin before its host sediment particles are deposited and permanently located, at least for a few hundred years. As much as 90% of the initially deposited Pu will remain, redistributed over the landscape by erosion and deposition. Although the delivery rate of Pu by rivers will not decrease greatly in the next 100 yr, a significant decrease will likely occur by 1000 yr

  10. LEGACY - EOP Marine Debris

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data contains towed diver surveys of and weights of marine debris removed from the near shore environments of the NWHI.

  11. Fallout: The experiences of a medical team in the care of a Marshallese population accidently exposed to fallout radiation

    International Nuclear Information System (INIS)

    Conard, R.A.

    1992-09-01

    This report presents an historical account of the experiences of the Brookhaven Medical Team in the examination and treatment of the Marshallese people following their accidental exposure to radioactive fallout in 1954. This is the first time that a population has been heavily exposed to radioactive fallout, and even though this was a tragic mishap, the medical findings have provided valuable information for other accidents involving fallout such as the recent reactor accident at Chernobyl. Noteworthy has been the unexpected importance of radioactive iodine in the fallout in producing thyroid abnormalities

  12. Fallout: The experiences of a medical team in the care of a Marshallese population accidentally exposed to fallout radiation

    International Nuclear Information System (INIS)

    Conard, R.A.

    1991-01-01

    This report presents an historical account of the experiences of the Brookhaven Medical team in the examination and treatment of the Marshallese people following their accidental exposure to radioactive fallout in 1954. This is the first time that a population has been heavily exposed to radioactive fallout, and even though this was a tragic mishap, the medical findings have provided valuable information for other accidents involving fallout such as the recent reactor accident at Chernobyl. Particularly important has been the unexpected importance of radioactive iodine in the fallout in producing thyroid abnormalities

  13. Fallout: The experiences of a medical team in the care of a Marshallese population accidentally exposed to fallout radiation

    Energy Technology Data Exchange (ETDEWEB)

    Conard, R.A.

    1991-12-31

    This report presents an historical account of the experiences of the Brookhaven Medical team in the examination and treatment of the Marshallese people following their accidental exposure to radioactive fallout in 1954. This is the first time that a population has been heavily exposed to radioactive fallout, and even though this was a tragic mishap, the medical findings have provided valuable information for other accidents involving fallout such as the recent reactor accident at Chernobyl. Particularly important has been the unexpected importance of radioactive iodine in the fallout in producing thyroid abnormalities.

  14. Fallout: The experiences of a medical team in the care of a Marshallese population accidentally exposed to fallout radiation

    Energy Technology Data Exchange (ETDEWEB)

    Conard, R.A.

    1991-01-01

    This report presents an historical account of the experiences of the Brookhaven Medical team in the examination and treatment of the Marshallese people following their accidental exposure to radioactive fallout in 1954. This is the first time that a population has been heavily exposed to radioactive fallout, and even though this was a tragic mishap, the medical findings have provided valuable information for other accidents involving fallout such as the recent reactor accident at Chernobyl. Particularly important has been the unexpected importance of radioactive iodine in the fallout in producing thyroid abnormalities.

  15. Fallout: The experiences of a medical team in the care of a Marshallese population accidently exposed to fallout radiation

    Energy Technology Data Exchange (ETDEWEB)

    Conard, R.A.

    1992-09-01

    This report presents an historical account of the experiences of the Brookhaven Medical Team in the examination and treatment of the Marshallese people following their accidental exposure to radioactive fallout in 1954. This is the first time that a population has been heavily exposed to radioactive fallout, and even though this was a tragic mishap, the medical findings have provided valuable information for other accidents involving fallout such as the recent reactor accident at Chernobyl. Noteworthy has been the unexpected importance of radioactive iodine in the fallout in producing thyroid abnormalities.

  16. Radioactive fallout and neural tube defects | Akar | Egyptian Journal ...

    African Journals Online (AJOL)

    Possible link between radioactivity and the occurrence of neural tube defects is a long lasting debate since the Chernobyl nuclear fallout in 1986. A recent report on the incidence of neural defects in the west coast of USA, following Fukushima disaster, brought another evidence for effect of radioactive fallout on the ...

  17. The isotopic signature of fallout plutonium in the North Pacific

    International Nuclear Information System (INIS)

    Buesseler, K.O.

    1997-01-01

    Plutonium analyses of a dated coral record from the French Frigate Shoals in the central North Pacific indicate that there are two major sources of Pu in this basin: close-in (tropospheric) fallout from nuclear weapons testing at the Pacific Proving Grounds in the Marshall Islands in the 1950s and global (stratospheric) fallout which peaked in 1962. Furthermore, the 240 Pu/ 239 Pu atom ratio of fallout from the Pacific Proving Grounds is characteristically higher (0.24) than that of global fallout Pu (0.18-0.19). Seawater and sediment samples from the North Pacific exhibit a wide range of 240 Pu/ 239 Pu values (0.19-0.34), with a trend towards higher ratios in the subsurface waters and sediment. Deep water 240 Pu/ 239 Pu ratios are higher in the vicinity of the Marshall Islands relative to stations further from this close-in fallout source. These preliminary data suggest that fallout Pu from the Pacific Proving Grounds is more rapidly removed from the surface waters than is global fallout Pu. Plutonium geochemistry appears to be related to the physical/chemical form of Pu-bearing particles generated by different fallout sources. (author)

  18. The isotopic signature of fallout plutonium in the North Pacific

    Energy Technology Data Exchange (ETDEWEB)

    Buesseler, K.O. [Woods Hole Oceanographic Institution, MA (United States)

    1997-07-01

    Plutonium analyses of a dated coral record from the French Frigate Shoals in the central North Pacific indicate that there are two major sources of Pu in this basin: close-in (tropospheric) fallout from nuclear weapons testing at the Pacific Proving Grounds in the Marshall Islands in the 1950s and global (stratospheric) fallout which peaked in 1962. Furthermore, the {sup 240}Pu/{sup 239}Pu atom ratio of fallout from the Pacific Proving Grounds is characteristically higher (0.24) than that of global fallout Pu (0.18-0.19). Seawater and sediment samples from the North Pacific exhibit a wide range of {sup 240}Pu/{sup 239}Pu values (0.19-0.34), with a trend towards higher ratios in the subsurface waters and sediment. Deep water {sup 240}Pu/{sup 239}Pu ratios are higher in the vicinity of the Marshall Islands relative to stations further from this close-in fallout source. These preliminary data suggest that fallout Pu from the Pacific Proving Grounds is more rapidly removed from the surface waters than is global fallout Pu. Plutonium geochemistry appears to be related to the physical/chemical form of Pu-bearing particles generated by different fallout sources. (author).

  19. Fallout total. beta. radioactivity in every rainfall in Aichi prefecture

    Energy Technology Data Exchange (ETDEWEB)

    Ohnuma, Shoko; Chaya, Kunio; Shimizu, Michihiko; Tomita, Ban-ichi; Hamamura, Norikatsu (Aichi Prefectural Inst. of Public Health, Nagoya (Japan))

    1983-01-01

    Fallout total ..beta.. radioactivity was measured in every rainfall in the period from 1962 to 1981. Maximum value of monthly fallout was 462 mCi/km/sup 2/ at May 1966. Considering changes of monthly fallout, it was assumed that these 20 years were divided to 3 periods and these changes reflected the history of nuclear explosion tests in the world. Maximum value of annual fallout was 1,154 mCi/km/sup 2/ in 1963. Average of annual fallout in 1973 to 1981 was about 1/40 of maximum value. It was confirmed that changes of annual fallout were almost corresponded with changes of annual deposition of /sup 90/Sr and /sup 137/Cs in Tokyo reported by Katsuragi et al. Estimating the staying time of /sup 90/Sr and /sup 137/Cs at Stratosphere by the use of annual fallout of total ..beta.. radioactivity and annual deposition of these radionuclides, /sup 90/Sr was 1.3 years and /sup 137/Cs was 1.5 years. Also, annual correlation between monthly fallout and monthly rainfall was regarded as significant in only 6 years of these 20 years.

  20. Fallout total β radioactivity in every rainfall in Aichi prefecture

    International Nuclear Information System (INIS)

    Ohnuma, Shoko; Chaya, Kunio; Shimizu, Michihiko; Tomita, Ban-ichi; Hamamura, Norikatsu

    1983-01-01

    Fallout total β radioactivity was measured in every rainfall in the period from 1962 to 1981. Maximum value of monthly fallout was 462 mCi/km 2 at May 1966. Considering changes of monthly fallout, it was assumed that these 20 years were divided to 3 periods and these changes reflected the history of nuclear explosion tests in the world. Maximum value of annual fallout was 1,154 mCi/km 2 in 1963. Average of annual fallout in 1973 to 1981 was about 1/40 of maximum value. It was confirmed that changes of annual fallout were almost corresponded with changes of annual deposition of 90 Sr and 137 Cs in Tokyo reported by Katsuragi et al. Estimating the staying time of 90 Sr and 137 Cs at Stratosphere by the use of annual fallout of total β radioactivity and annual deposition of these radionuclides, 90 Sr was 1.3 years and 137 Cs was 1.5 years. Also, annual correlation between monthly fallout and monthly rainfall was regarded as significant in only 6 years of these 20 years. (author)

  1. Hygienic estimation of population doses due to stratospheric fallout

    International Nuclear Information System (INIS)

    Marej, A.N.; Knizhnikov, V.A.

    1980-01-01

    The hygienic estimation of external and internal irradiation of the USSR population due to stratospheric global fallouts of fission products after nuclear explosions and weapon tests, is carried out. Numerical values which characterize the dose-effect dependence in the case of radiation of marrow, bone tissue and whole body are presented. Values of mean individual and population doses of irradiation due to global fallouts within 1963-1975, types of injury and the number of mortal cases due to malignant neoplasms are presented. A conclusion is made that the contribution of radiation due to stratospheric fallouts in the mortality due to malignant neoplasms is insignificant. Annual radiation doses, conditioned by global fallouts within the period of 1963-1975 constitute but several percent from the dose of radiation of the natural radiation background. Results of estimation of genetic consequences of irradiation due to atmospheric fallouts are presented

  2. Space Debris & its Mitigation

    Science.gov (United States)

    Kaushal, Sourabh; Arora, Nishant

    2012-07-01

    Space debris has become a growing concern in recent years, since collisions at orbital velocities can be highly damaging to functioning satellites and can also produce even more space debris in the process. Some spacecraft, like the International Space Station, are now armored to deal with this hazard but armor and mitigation measures can be prohibitively costly when trying to protect satellites or human spaceflight vehicles like the shuttle. This paper describes the current orbital debris environment, outline its main sources, and identify mitigation measures to reduce orbital debris growth by controlling these sources. We studied the literature on the topic Space Debris. We have proposed some methods to solve this problem of space debris. We have also highlighted the shortcomings of already proposed methods by space experts and we have proposed some modification in those methods. Some of them can be very effective in the process of mitigation of space debris, but some of them need some modification. Recently proposed methods by space experts are maneuver, shielding of space elevator with the foil, vaporizing or redirecting of space debris back to earth with the help of laser, use of aerogel as a protective layer, construction of large junkyards around international space station, use of electrodynamics tether & the latest method proposed is the use of nano satellites in the clearing of the space debris. Limitations of the already proposed methods are as follows: - Maneuvering can't be the final solution to our problem as it is the act of self-defence. - Shielding can't be done on the parts like solar panels and optical devices. - Vaporizing or redirecting of space debris can affect the human life on earth if it is not done in proper manner. - Aerogel has a threshold limit up to which it can bear (resist) the impact of collision. - Large junkyards can be effective only for large sized debris. In this paper we propose: A. The Use of Nano Tubes by creating a mesh

  3. Changing atmospheric fallout of magnetic particles recorded in recent ombrotrophic peat sections.

    Science.gov (United States)

    Oldfield, F; Thompson, R; Barber, K E

    1978-02-10

    Magnetic measurements of ombrotrophic peat allow a reconstruction of changes in the past fallout of magnetic particles through the atmosphere. In recent peat profiles from three sites in Britain and Northern Ireland, a marked increase in saturated isothermal remanent magnetization of the peat is recorded in levels which can be shown to postdate the onset of the Industrial Revolution. Furthermore the spatial variation in contemporary isothermal remanent magnetization values is consistent with a recent industrial and urban origin for the bulk of the magnetic minerals present. Pre-Industrial Revolution values are between two and three orders of magnitude lower, suggesting that the natural cosmic and terrestrial sources previously cited for such material have been dominated in recent times by the products of human activity. Magnetic measurements provide a simple, rapid, and nondestructive method of monitoring and differentiating various types of particulate atmospheric fallout for both recent and preindustrial times.

  4. Measurements of atmospheric fallout in Argentina

    International Nuclear Information System (INIS)

    Canoba, A.C.; Lopez, F.O.; Bruno, H.A.

    1998-01-01

    With the purpose of studying the radioactive fallout present in Argentina from atmospheric nuclear explosions tests that have been conducted recently, an environmental monitoring program, outside the influence of nuclear facilities of Argentina, was undertaken during 1996 and 1997. The levels of Cs-137 and Sr-90 were analysed in samples of air, deposited material (rainwater), milk, an average meal of a standard man and food. During this period, a total of 630 radiochemical analysis were performed on 325 samples of the different matrices described. The concentration levels of the radionuclides analysed in the different environmental matrices are presented and are compared with the values obtained in the environmental monitoring program done during the period 1960-1981. (author) [es

  5. Fallout radiation protection provided by transportation vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Burson, Z.G.

    1972-10-20

    Fallout radiation protection factors (PF's) were estimated for a variety of civilian transportation vehicles using measurements of the natural terrain radiation as a source. The PF values are below 2 in light vehicles, truck beds, or trailers; from 2.5 to 3 in the cabs of heavy trucks and in a railway guard car; and from 3.0 to 3.5 in the engineer's seat of heavy locomotives. This information can be useful in planning the possible movement of personnel from or through areas contaminated either by a wartime incident or a peacetime accident. The information may also be useful for studying the reduction of exposure to the natural terrestrial radiation environment provided by vehicles.

  6. 111Ag in the Chernobyl fallout

    International Nuclear Information System (INIS)

    Winkler, R.; Rosner, G.; Hoetzl, H.

    1989-01-01

    In the course of a re-evalution of the gamma-ray spectra of air filter samples collected immediately after Chernobyl accident at Munich-Neuherberg 111 Ag has been found to contribute significantly to the total activity within the first days of the Chernobyl fallout. The maximum air concentration was measured on 1 May 1986 to be 5.4 Bq/m 3 compared with 9.7 Bq 137 Cs per m 3 . Referred to this date the total activity deposition to ground was 12±3 kBq 111 Ag per m 2 . Referred to 26 April 1986 the 111 Ag to 110m Ag ratio was found to be 53±3 and the 111 Ag to 137 Cs ratio was 1.0±0.1. It is estimated that the cesium isotopes were depleted during release and atmospheric transport by a factor of about 2 compared with the silver isotopes. (orig.)

  7. Impact of the Chernobyl fallout in the alpine environment

    International Nuclear Information System (INIS)

    Gastberger, M.; Lettner, H.; Hofmann, W.; Pohl-Rueling, J.; Steinhaeusler, N.F.; Hubmer, A.

    1997-01-01

    In Austria the alpine regions received the highest fallout contamination, showing a very inhomogeneous spatial distribution of the surface deposition. About half of the national territory is within alpine regions, which are very different in times of underlying bedrock and soil characteristic. Since this is the controlling factor for the radionuclide uptake of the vegetation, it is crucial for the long-term effects of radioactive fallout. Different studies have been carried out in the Province of Salzburg (area: 7154 km 2 ) over the past ten years, addressing a broad spectrum of issues, such as: measurement of the spatial distribution of the fallout, research in monitoring techniques comparison of theoretical calculations with actual in vivo-measurements of nuclide uptake by man for different population groups, and the investigation of biological effects. When considering the radioecological effects of the Chernobyl fallout a distinction has to be made between the short-term effects immediately following the fallout and the long-term effects. While the short term effects are controlled by the physical characteristics of the fallout, similar for the whole region, the long-term effects are more determined by the radioecological properties of the environments affected which are much more variable than the fallout-characteristics

  8. Disaster Debris Recovery Database - Landfills

    Data.gov (United States)

    U.S. Environmental Protection Agency — The US EPA Disaster Debris Recovery Database (DDRD) promotes the proper recovery, recycling, and disposal of disaster debris for emergency responders at the federal,...

  9. Disaster Debris Recovery Database - Recovery

    Data.gov (United States)

    U.S. Environmental Protection Agency — The US EPA Disaster Debris Recovery Database (DDRD) promotes the proper recovery, recycling, and disposal of disaster debris for emergency responders at the federal,...

  10. Space Debris Mitigation Guidelines

    Science.gov (United States)

    Johnson, Nicholas L.

    2011-01-01

    The purpose of national and international space debris mitigation guides is to promote the preservation of near-Earth space for applications and exploration missions far into the future. To accomplish this objective, the accumulation of objects, particularly in long-lived orbits, must be eliminated or curtailed.

  11. Reconstruction and analysis of 137Cs fallout deposition patterns in the Marshall Islands.

    Science.gov (United States)

    Whitcomb, Robert C

    2002-03-01

    Estimates of 137Cs deposition caused by fallout originating from nuclear weapons testing in the Marshall Islands have been estimated for several locations in the Marshall Islands. These retrospective estimates are based primarily on historical exposure rate and gummed film measurements. The methods used to reconstruct these deposition estimates are similar to those used in the National Cancer Institute study for reconstructing 131I deposition from the Nevada Test Site. Reconstructed cumulative deposition estimates are validated against contemporary measurements of 137Cs concentration in soil with account taken for estimated global fallout contributions. These validations show that the overall geometric bias in predicted-to-observed (P:O) ratios is 1.0 (indicating excellent agreement). The 5th to 95th percentile range of this distribution is 0.35-2.95. The P:O ratios for estimates using historical gummed film measurements tend to slightly overpredict more than estimates using exposure rate measurements. The deposition estimate methods, supported by the agreement between estimates and measurements, suggest that these methods can be used with confidence for other weapons testing fallout radionuclides.

  12. Nevada Test Site fallout in the area of Enterprise, Utah

    International Nuclear Information System (INIS)

    Krey, P.W.; Hardy, E.P.; Heit, M.

    1980-04-01

    The analysis of a sediment core from the Enterprise reservoir in southwestern Utah has provided a record of fallout in the area dating to 1945. Assming that all the 137 Cs fallout that occurred at Enterprise reservoir between 1951 and 1957 came exclusively from the Nevada tests, an upper limit of the integrated deposit from this source is 18 mCi/km 2 of 137 Cs decay corrected to 1979 out of a total of 101 measured in 1979. The maximum infinity dose from the external radiation caused by this Nevada Test Site fallout is estimated to be 1700 mrad. This maximum dose is only a factor of two higher than the cumulative estimated dose in Enterprise derived from the radiological surveys conducted after each test. This indicates that the region around Enterprise reservoir did not experience an intrusion of fallout from NTS greatly in excess of what had been deduced from the post-shot external radiation surveys

  13. gamma. -spectra of radioactive fallout from the atmosphere. [In German

    Energy Technology Data Exchange (ETDEWEB)

    Herbst, W; Sommermeyer, K

    1957-01-01

    Foils used for collecting dust which were exposed to radioactive fallout for 8 days, and grass ashes exhibit the same ..gamma..-spectra. The peaks were characteristic of the following isotopes, half-lives in brackets: /sup 140/Ba (13 days) + /sup 140/La; /sup 95/Zr (65 days) + /sup 95/Nb; and /sup 103/Ru (40 days). Relative peak heights indicated age of fallout.

  14. Impact of fallout from Chernobyl on Saclay site

    International Nuclear Information System (INIS)

    1986-07-01

    The fallout from Chernobyl accident have been monitored at Saclay Nuclear Research Center. The initial results from external irradiation measurement and analysis of environmental samples: air, fallout deposits, surface water, drinking water, underground water, food chain, are presented. The population radiation doses from external exposure to the plume, inhaled radioactivity and consumption of meat, milk and vegetables have been estimated. Special monitoring of internal contamination by iodine 131, cesium 134 and cesium 137 has been carried out using whole body counting [fr

  15. Ingestion of Nevada Test Site Fallout: Internal dose estimates

    International Nuclear Information System (INIS)

    Whicker, F.W.; Kirchner, T.B.; Anspaugh, L.R.

    1996-01-01

    This paper summarizes individual and collective dose estimates for the internal organs of hypothetical yet representative residents of selected communities that received measurable fallout from nuclear detonations at the Nevada Test Site. The doses, which resulted from ingestion of local and regional food products contaminated with over 20 radionuclides, were estimated with use of the PATHWAY food-chain-transport model to provide estimates of central tendency and uncertainty. The thyroid gland received much higher doses than other internal organs and tissues. In a avery few cases, infants might have received thyroid doses in excess of 1 Gy, depending on location, diet, and timing of fallout. 131 I was the primary thyroid dose contributor, and fresh milk was the main exposure pathway. With the exception of the thyroid, organ doses from the ingestion pathway were much smaller (<3%) than those from external gamma exposure to deposited fallout. Doses to residents living closest to the Nevada Test Site were contributed mainly by a few fallout events; doses to more distantly located people were generally smaller, but a greater number of events provided measurable contributions. The effectiveness of different fallout events in producing internal organ doses through ingestion varied dramatically with seasonal timing of the test, with maximum dose per unit fallout occurring for early summer depositions when milk cows were on pasture and fresh, local vegetables were used. Within specific communities, internal doses differed by age, sex, and lifestyle. Collective internal dose estimates for specific geographic areas are provided

  16. Childhood leukemias associated with fallout from nuclear testing

    International Nuclear Information System (INIS)

    Lyon, J.L.; Klauber, M.R.; Gardner, J.W.; Udall, K.S.

    1979-01-01

    Continuing concern over the possible carcinogenic effects of low-level radiation prompted us to study the population of Utah because of its exposure to fallout from 26 nuclear tests between 1951 and 1958. Certain rural counties (high-level counties) received most of the fallout during that period. We reviewed all deaths from childhood (under 15 years of age) cancers occurring in the entire state between 1944 and 1975 and assigned them to a cohort of either high or low exposure, depending on whether 15 between 1951 and 1958. For reasons unknown, leukemia mortality among the low-exposure cohort in the high-fallout counties was about half that of the United States and the remainder of the state. Mortality increased by 2.44 times (95 per cent confidence, 1.18 to 5.02) to just slightly above that of the United States in the high-exposure cohort residing in the high-fallout counties, and was greatest in 10- to 14-year-old children. For other childhood cancers, no consistent pattern was found in relation to fallout exposure. The increase in leukemia deaths could be due to fallout or to some other unexplained factor

  17. Radioactive fallout in food and agriculture

    International Nuclear Information System (INIS)

    Winteringham, F.P.W.

    1989-01-01

    Part 1 of this review is designed to provide an up-dated background to the subject in relation to FAO's interests and responsibilities in scientifically accurate but non-technical language. Part 2 is concerned more specifically with the problems of radioactive fallout over pasture and cultivated soils. Moreover, it is mainly concerned with problems of international significance under peacetime conditions and which are likely only to arise as a result of a major nuclear reactor accident, or, possibly, some unintended nuclear explosion. However, relatively local problems of soil contamination could arise as a result of other kinds of accident. In the report the natural occurrence of radionuclides, and radiation exposure as a fact of life in the human environment, are indicated. Exposure to ionizing radiation from natural and man-made sources are compared. The behaviour and significance of radionuclides in ecosystems are briefly illustrated. Land-based nuclear powr stations and nuclear-powered ships and submarines are identified as the major potential accident hazards to agriculture or fisheries under peacetime conditions. 216 refs, figs and tabs

  18. Fallout Concentration Various Environmental Samples in Indonesia

    International Nuclear Information System (INIS)

    Sutarman

    2001-01-01

    The testing of nuclear weapons have been carried out by the advanced countries, such as United States, Russian Federation, United Kingdom, France, China, India and Pakistan, since about 1945 until 1998. Nuclear weapons tests were conducted at various locations, on and above the earth's surface or underground or on and under the ocean's surface. Nuclear explosions caused the radionuclides of fission product, such as 131 l, 89 Sr, 90 Sr, 134 Cs, 137 Cs, and 239 Pu released to the atmospheric layer. In the atmospheric layer, the long-lived radionuclides, i.e, 90 Sr dan 137 Cs will be distributed into the environment as the fallout radionuclides, and deposited in the various environmental samples (soil, water, and biota). In general, at several locations in Indonesia the 90 Sr and 137 Cs in the various environmental samples still can be detected. The data of measurement results of 90 Sr and 137 Cs concentrations were generally lower than that from some countries in the northern hemisphere. (author)

  19. Fallout 3H ingestion in Akita, Japan

    International Nuclear Information System (INIS)

    Hisamatsu, S.; Takizawa, Y.; Abe, T.; Katsumata, T.

    1987-01-01

    To study fallout 3 H ingestion in Japan, 16 separate food group samples were collected from Akita during 1985. The 3 H concentration in free water and that in a tissue-bound form were determined separately. The average 3 H concentration in the tissue-bound form was 2.2 Bq L-1, 1.7 times higher than in the free water of the food. The ingestions of 3 H in the tissue-bound form and as free water in the diet were 0.60 Bq d-1 and 1.0 Bq d-1, respectively. Cereals represented the food group that contributed the most to the ingestion of tissue-bound 3 H. Total 3 H ingestion was estimated to be 4.1 Bq d-1. The contribution of the tissue-bound form to the total ingestion was 15%, considerably lower than reported for Italian diets. The ratio of 3 H ingestion in the tissue-bound form to the free water form in the diet was similar to the ratio reported for New York City

  20. Tracing the Iodine-129 fallout in Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez Niello, Jorge; Negri, Agustin; Arazi, Andres [Comision Nacional de Energia Atomica (CNEA), Buenos Aires (Argentina). Lab. TANDAR; Wallner, Anton [The Australian National University, Canberra (Australia). Dept. of Nuclear Physics; Niello, Jorge Fernandez [Universidad Nacional de San Martin, Campus Miguelete, Buenos Aires (Argentina)

    2012-07-01

    Full text: Long-lived {sup 129}I (half-life=15.6 Ma) is produced naturally by irradiation of atmospheric xenon by cosmic neutrons and in the sub-surface by spontaneous fission of {sup 238}U, from which the natural inventory of {sup 129}I has been estimated to be around 50,000 kg, only 140 kg of them corresponds to the hydrospheric inventory. Nuclear tests and accidents have added between 45-130 kg. Apart from a global atmospheric fallout component, {sup 129}I has been released from several nuclear fuel reprocessing plants located in the Northern Hemisphere (ca. 6000 kg) which serve as localized sources in oceanographic-tracer experiments. In this presentation, we report results from a study exploring the presence of {sup 129}I in the Southern Hemisphere by determining {sup 129}I/{sup 127}I isotopic ratios in water samples (rivers, lakes and shallow sea-water) taken at different latitudes in Argentina including Antarctica. The iodine-127 and iodine-129 concentrations were measured via ICP-MS (Inductively Coupled Plasma Mass Spectrometry) and Accelerator Mass Spectrometry (AMS), respectively. Distribution of both isotopes can be understood considering tropospheric circulation patterns, possible sources and regional precipitation patterns. Natural and anthropogenic sources for the Southern Hemisphere and their inventories are discussed. Similar contribution came from natural sources and nuclear tests. Contribution from the nuclear fuel reprocessing plants placed in the Northern hemisphere can be neglected. (author)

  1. sup 111 Ag in the Chernobyl fallout

    Energy Technology Data Exchange (ETDEWEB)

    Winkler, R.; Rosner, G.; Hoetzl, H. (Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen, Neuherberg (Germany, F.R.). Inst. fuer Strahlenschutz)

    1989-01-01

    In the course of a re-evalution of the gamma-ray spectra of air filter samples collected immediately after Chernobyl accident at Munich-Neuherberg {sup 111}Ag has been found to contribute significantly to the total activity within the first days of the Chernobyl fallout. The maximum air concentration was measured on 1 May 1986 to be 5.4 Bq/m{sup 3} compared with 9.7 Bq {sup 137}Cs per m{sup 3}. Referred to this date the total activity deposition to ground was 12{plus minus}3 kBq {sup 111}Ag per m{sup 2}. Referred to 26 April 1986 the {sup 111}Ag to {sup 110m}Ag ratio was found to be 53{plus minus}3 and the {sup 111}Ag to {sup 137}Cs ratio was 1.0{plus minus}0.1. It is estimated that the cesium isotopes were depleted during release and atmospheric transport by a factor of about 2 compared with the silver isotopes. (orig.).

  2. Neogene fallout tuffs from the Yellowstone hotspot in the Columbia Plateau region, Oregon, Washington and Idaho, USA.

    Directory of Open Access Journals (Sweden)

    Barbara P Nash

    Full Text Available Sedimentary sequences in the Columbia Plateau region of the Pacific Northwest ranging in age from 16-4 Ma contain fallout tuffs whose origins lie in volcanic centers of the Yellowstone hotspot in northwestern Nevada, eastern Oregon and the Snake River Plain in Idaho. Silicic volcanism began in the region contemporaneously with early eruptions of the Columbia River Basalt Group (CRBG, and the abundance of widespread fallout tuffs provides the opportunity to establish a tephrostratigrahic framework for the region. Sedimentary basins with volcaniclastic deposits also contain diverse assemblages of fauna and flora that were preserved during the Mid-Miocene Climatic Optimum, including Sucker Creek, Mascall, Latah, Virgin Valley and Trout Creek. Correlation of ashfall units establish that the lower Bully Creek Formation in eastern Oregon is contemporaneous with the Virgin Valley Formation, the Sucker Creek Formation, Oregon and Idaho, Trout Creek Formation, Oregon, and the Latah Formation in the Clearwater Embayment in Washington and Idaho. In addition, it can be established that the Trout Creek flora are younger than the Mascall and Latah flora. A tentative correlation of a fallout tuff from the Clarkia fossil beds, Idaho, with a pumice bed in the Bully Creek Formation places the remarkably well preserved Clarkia flora assemblage between the Mascall and Trout Creek flora. Large-volume supereruptions that originated between 11.8 and 10.1 Ma from the Bruneau-Jarbidge and Twin Falls volcanic centers of the Yellowstone hotspot in the central Snake River Plain deposited voluminous fallout tuffs in the Ellensberg Formation which forms sedimentary interbeds in the CRBG. These occurrences extend the known distribution of these fallout tuffs 500 km to the northwest of their source in the Snake River Plain. Heretofore, the distal products of these large eruptions had only been recognized to the east of their sources in the High Plains of Nebraska and Kansas.

  3. A MODEL BUILDING CODE ARTICLE ON FALLOUT SHELTERS WITH RECOMMENDATIONS FOR INCLUSION OF REQUIREMENTS FOR FALLOUT SHELTER CONSTRUCTION IN FOUR NATIONAL MODEL BUILDING CODES.

    Science.gov (United States)

    American Inst. of Architects, Washington, DC.

    A MODEL BUILDING CODE FOR FALLOUT SHELTERS WAS DRAWN UP FOR INCLUSION IN FOUR NATIONAL MODEL BUILDING CODES. DISCUSSION IS GIVEN OF FALLOUT SHELTERS WITH RESPECT TO--(1) NUCLEAR RADIATION, (2) NATIONAL POLICIES, AND (3) COMMUNITY PLANNING. FALLOUT SHELTER REQUIREMENTS FOR SHIELDING, SPACE, VENTILATION, CONSTRUCTION, AND SERVICES SUCH AS ELECTRICAL…

  4. ORDEM2010 and MASTER-2009 Modeled Small Debris Population Comparison

    Science.gov (United States)

    Krisko, Paula H.; Flegel, S.

    2010-01-01

    The latest versions of the two premier orbital debris engineering models, NASA s ORDEM2010 and ESA s MASTER-2009, have been publicly released. Both models have gone through significant advancements since inception, and now represent the state-of-the-art in orbital debris knowledge of their respective agencies. The purpose of these models is to provide satellite designers/operators and debris researchers with reliable estimates of the artificial debris environment in near-Earth orbit. The small debris environment within the size range of 1 mm to 1 cm is of particular interest to both human and robotic spacecraft programs. These objects are much more numerous than larger trackable debris but are still large enough to cause significant, if not catastrophic, damage to spacecraft upon impact. They are also small enough to elude routine detection by existing observation systems (radar and telescope). Without reliable detection the modeling of these populations has always coupled theoretical origins with supporting observational data in different degrees. This paper details the 1 mm to 1 cm orbital debris populations of both ORDEM2010 and MASTER-2009; their sources (both known and presumed), current supporting data and theory, and methods of population analysis. Fluxes on spacecraft for chosen orbits are also presented and discussed within the context of each model.

  5. Modelling the fate of marine debris along a complex shoreline: Lessons from the Great Barrier Reef

    Science.gov (United States)

    Critchell, K.; Grech, A.; Schlaefer, J.; Andutta, F. P.; Lambrechts, J.; Wolanski, E.; Hamann, M.

    2015-12-01

    The accumulation of floating anthropogenic debris in marine and coastal areas has environmental, economic, aesthetic, and human health impacts. Until now, modelling the transport of such debris has largely been restricted to the large-scales of open seas. We used oceanographic modelling to identify potential sites of debris accumulation along a rugged coastline with headlands, islands, rocky coasts and beaches. Our study site was the Great Barrier Reef World Heritage Area that has an emerging problem with debris accumulation. We found that the classical techniques of modelling the transport of floating debris models are only moderately successful due to a number of unknowns or assumptions, such as the value of the wind drift coefficient, the variability of the oceanic forcing and of the wind, the resuspension of some floating debris by waves, and the poorly known relative contribution of floating debris from urban rivers and commercial and recreational shipping. Nevertheless the model was successful in reproducing a number of observations such as the existence of hot spots of accumulation. The orientation of beaches to the prevailing wind direction affected the accumulation rate of debris. The wind drift coefficient and the exact timing of the release of the debris at sea affected little the movement of debris originating from rivers but it affected measurably that of debris originating from ships. It was thus possible to produce local hotspot maps for floating debris, especially those originating from rivers. Such modelling can be used to inform local management decisions, and it also identifies likely priority research areas to more reliably predict the trajectory and landing points of floating debris.

  6. The coefficients of the damping in the radioactive fall-out

    International Nuclear Information System (INIS)

    Stofanova, M.; Usacev, S.

    1977-01-01

    Radioactive fallout is characterized by time and seasonal variations. So far the independent growth of the 3 H, 90 Sr and 14 C fallout maxima was studied separately. The maxima and minima of the total fallout were compared with that of the above mentioned isotopes. Introducing the damping coefficient for monthly fallout, the seasonal and annual damping coefficients made is possible to determine time difference of the maxima of fallout for the individual components, namely: 3 H, 90 Sr and 14 C. Calculation of these coefficients yielded graphs markedly differentiating the maxima of the gross β activities for the years 1959 to 1973 and the said components of fallout. (author)

  7. Persistent marine debris

    International Nuclear Information System (INIS)

    Levy, E.M.

    1992-01-01

    In this paper the distribution of persistent marine debris, adrift on world oceans and stranded on beaches globally, is reviewed and related to the known inputs and transport by the major surface currents. Since naturally occurring processes eventually degrade petroleum in the environment, international measures to reduce the inputs have been largely successful in alleviating oil pollution on a global, if not on a local, scale. Many plastics, however, are so resistant to natural degradation that merely controlling inputs will be insufficient, and more drastic and costly measures will be needed to cope with the emerging global problem posed by these materials

  8. Dose estimation from residual and fallout radioactivity, 1

    International Nuclear Information System (INIS)

    Takeshita, Kenji

    1975-01-01

    External dose rates and cumulative doses for early entrants from areal surveys and simulated experiments are reviewed. The average cumulative doses to infinity at the hypocenters were 101 rad in Hiroshima and 32 rad in Nagasaki, with a variation of about 60 percent. Radioactive fallout areas nearly matched the ''black rain'' areas in Nagasaki and in Hiroshima. Radioactivity in the fallout areas was affected by radioactive decay and by the leaching and dissipation by rains. Considering these factors, the cumulative dose to infinity in the fallout area of Hiroshima was estimated to be 13 rad, excluding internal radiation doses from inhaled and ingested radionuclides. Attempts to estimate radiation dose from internally deposited radionuclides are also described. (auth.)

  9. Sediment-associated transport and redistribution of Chernobyl fallout radionuclides

    International Nuclear Information System (INIS)

    Walling, D.E.; Rowan, J.S.; Bradley, S.B.

    1989-01-01

    Fallout of Chernobyl-derived radionuclides over the United Kingdom evidenced marked spatial variation. Relatively high levels were recorded in central Wales, but they declined rapidly to the east. As a result the headwaters of the River Severn received significant inputs of fallout, whereas only low levels were recorded over the middle and lower reaches. Measurements of the caesium-137 content of suspended sediment transported by the River Severn and of channel and floodplain sediments collected from various locations within the basin have been used to assess the importance of fluvial transport and redistribution of Chernobyl-derived radionuclides. High concentrations of caesium-137 (up to 1450 mBqg -1 ) were recorded in suspended sediment collected from the lower reaches of the river shortly after the Chernobyl incident and substantial accumulations of Chernobyl-derived radionuclides have been detected in floodplain and channel sediments collected from areas which received only low levels of fallout directly. (author)

  10. Wholesale debris removal from LEO

    Science.gov (United States)

    Levin, Eugene; Pearson, Jerome; Carroll, Joseph

    2012-04-01

    Recent advances in electrodynamic propulsion make it possible to seriously consider wholesale removal of large debris from LEO for the first time since the beginning of the space era. Cumulative ranking of large groups of the LEO debris population and general limitations of passive drag devices and rocket-based removal systems are analyzed. A candidate electrodynamic debris removal system is discussed that can affordably remove all debris objects over 2 kg from LEO in 7 years. That means removing more than 99% of the collision-generated debris potential in LEO. Removal is performed by a dozen 100-kg propellantless vehicles that react against the Earth's magnetic field. The debris objects are dragged down and released into short-lived orbits below ISS. As an alternative to deorbit, some of them can be collected for storage and possible in-orbit recycling. The estimated cost per kilogram of debris removed is a small fraction of typical launch costs per kilogram. These rates are low enough to open commercial opportunities and create a governing framework for wholesale removal of large debris objects from LEO.

  11. Childhood leukemia and fallout from the Nevada nuclear tests

    International Nuclear Information System (INIS)

    Land, C.E.; McKay, F.W.; Machado, S.G.

    1984-01-01

    Cancer mortality data from the National Center for Health Statistics, covering the period 1950 through 1978, were used to test a reported association between childhood leukemia and exposure to radioactive fallout from nuclear weapons tests in Nevada between 1951 and 1958. No pattern of temporal and geographic variation in risk supportive of the reported association was found. Comparison of these results with those presented in support of an association of risk with fallout suggests that the purported association merely reflects an anomalously low leukemia rate in southern Utah during the period 1944 to 1949. 14 references, 4 figures, 7 tables

  12. Radioactive fallout over South Africa during 1974-1983

    International Nuclear Information System (INIS)

    Brits, R.J.N.; Van der Bank, D.J.; Moolman, E.W.; Bain, C.A.R.; Van As, D.; Van derwesthuizen, G.S.H.

    1985-05-01

    NUCOR is routinely monitoring air and rainwater for radioactive fallout from atmospheric sources. Air humidity is continuously collected and analysed for tritium. Milk samples are obtained from a number of places throughout the country. These samples are analysed to detect timeously any build-up of radionuclides in soil and plants. Only a few atmosperic nuclear tests have been conducted (by China) since the previous report period of 1965 to 1973. The fallout from these sources over South Africa is extremely small and it is mainly cosmogenic radioactivity, viz 3 H and 7 Be, that is detected

  13. Transfer of fallout tritium from environment to human body

    International Nuclear Information System (INIS)

    Hisamatsu, Shun-ichi; Takizawa, Yukio

    1989-01-01

    A large quntity of tritium will be used as a fuel of nuclear fusion in the future. It is, therefore, considered important to elucidate tritium behavior present in the environment and the process of tritium transfer from the environment to the human body. Fallout tritium is an applicable material in searching for the long term behavior of tritium in the environment. This paper focuses on the American, Italian, Japanese literature concerning fallout tritium in food and in the human body. The specific activity ratio of bound to free tritium poses an important problem. The mechanism of biological concentration must await further studies. (N.K.) 63 refs

  14. A survey of radioactive fallout data in Alaska

    International Nuclear Information System (INIS)

    DePhillips, M.P.

    1995-01-01

    Considerable attention has been directed by the scientific community to assessing the levels and fate of radionuclides in Arctic ecosystems. The following text and tables present available data and discussion of radionuclide fallout in Alaska. A literature search of 23 on-line databases (Table 1) using Alaska, Strontium (Sr), Cesium (Cs), Plutonium (Pu) and Radionuclide as constraint terms responded with 177 possible citations. After eliminating duplicate citations, 31 articles were available: 17 were relevant to the subject matter; the remainder addressed geologic issues. All of the cited literature addressed 137 Cs, 90 Sr and 239,240 Pu as a result of radionuclide fallout from nuclear testing or accidental release

  15. Local fall-out and the animal food chain; Retombees locales et chaine alimentaire animale

    Energy Technology Data Exchange (ETDEWEB)

    Prat, G.; Mercier, F.J. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-07-01

    The local consequences of fresh fall-out, especially in the case of atmospheric nuclear explosions, are reviewed from the point of view of the internal contamination of the consumer of foodstuffs of animal origin. The edibility of foodstuffs derived from animals having grazed in the presence of fall-out is evaluated both from the wholesome and radio-toxicological points of view. The contamination level of these foodstuffs is calculated as a function of the ground fall-out, and of agronomical and ecological parameters for each radio-nuclide of the animal food chain. The internal exposure of the human consumer is calculated from this level as a function of the diet and of various parameters especially temporal. The equivalent dose to each critical organ, including the digestive tract is deduced from the burdens of each organ. From this a nutritional hygiene in the areas affected by fall-out is obtained, in relationship to the action levels fixed by the responsible authorities in exceptional circumstances. Criteria for these action levels are given as function of the food rations. (authors) [French] Les consequences locales des retombees fraiches, notamment dans le cas d'explosions nucleaires atmospheriques, sont passees en revue en ce qui concerne les problemes de contamination interne du consommateur de denrees d'origine animale. La comestibilite des aliments provenant de betes de boucherie ayant pature sous les retombees est evaluee au double point de vue de la salubrite et de la radiotoxicologie. Le niveau de contamination de ces denrees est calcule en fonction de la retombee au sol, des parametres agronomiques et ecologiques pour chaque radioelement de la chaine alimentaire animale. La contamination interne du consommateur humain est calculee a partir de ce niveau en fonction des modalites d'ingestion et de divers parametres, notamment temporels. L'equivalent de dose au niveau de chaque organe critique, y compris le tube digestif, est deduit

  16. Local fall-out and the animal food chain; Retombees locales et chaine alimentaire animale

    Energy Technology Data Exchange (ETDEWEB)

    Prat, G; Mercier, F J [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-07-01

    The local consequences of fresh fall-out, especially in the case of atmospheric nuclear explosions, are reviewed from the point of view of the internal contamination of the consumer of foodstuffs of animal origin. The edibility of foodstuffs derived from animals having grazed in the presence of fall-out is evaluated both from the wholesome and radio-toxicological points of view. The contamination level of these foodstuffs is calculated as a function of the ground fall-out, and of agronomical and ecological parameters for each radio-nuclide of the animal food chain. The internal exposure of the human consumer is calculated from this level as a function of the diet and of various parameters especially temporal. The equivalent dose to each critical organ, including the digestive tract is deduced from the burdens of each organ. From this a nutritional hygiene in the areas affected by fall-out is obtained, in relationship to the action levels fixed by the responsible authorities in exceptional circumstances. Criteria for these action levels are given as function of the food rations. (authors) [French] Les consequences locales des retombees fraiches, notamment dans le cas d'explosions nucleaires atmospheriques, sont passees en revue en ce qui concerne les problemes de contamination interne du consommateur de denrees d'origine animale. La comestibilite des aliments provenant de betes de boucherie ayant pature sous les retombees est evaluee au double point de vue de la salubrite et de la radiotoxicologie. Le niveau de contamination de ces denrees est calcule en fonction de la retombee au sol, des parametres agronomiques et ecologiques pour chaque radioelement de la chaine alimentaire animale. La contamination interne du consommateur humain est calculee a partir de ce niveau en fonction des modalites d'ingestion et de divers parametres, notamment temporels. L'equivalent de dose au niveau de chaque organe critique, y compris le tube digestif, est deduit des charges de ces

  17. Space debris: modeling and detectability

    Science.gov (United States)

    Wiedemann, C.; Lorenz, J.; Radtke, J.; Kebschull, C.; Horstmann, A.; Stoll, E.

    2017-01-01

    High precision orbit determination is required for the detection and removal of space debris. Knowledge of the distribution of debris objects in orbit is necessary for orbit determination by active or passive sensors. The results can be used to investigate the orbits on which objects of a certain size at a certain frequency can be found. The knowledge of the orbital distribution of the objects as well as their properties in accordance with sensor performance models provide the basis for estimating the expected detection rates. Comprehensive modeling of the space debris environment is required for this. This paper provides an overview of the current state of knowledge about the space debris environment. In particular non-cataloged small objects are evaluated. Furthermore, improvements concerning the update of the current space debris model are addressed. The model of the space debris environment is based on the simulation of historical events, such as fragmentations due to explosions and collisions that actually occurred in Earth orbits. The orbital distribution of debris is simulated by propagating the orbits considering all perturbing forces up to a reference epoch. The modeled object population is compared with measured data and validated. The model provides a statistical distribution of space objects, according to their size and number. This distribution is based on the correct consideration of orbital mechanics. This allows for a realistic description of the space debris environment. Subsequently, a realistic prediction can be provided concerning the question, how many pieces of debris can be expected on certain orbits. To validate the model, a software tool has been developed which allows the simulation of the observation behavior of ground-based or space-based sensors. Thus, it is possible to compare the results of published measurement data with simulated detections. This tool can also be used for the simulation of sensor measurement campaigns. It is

  18. Summary of Disposable Debris Shields (DDS) Analysis for Development of Solid Debris Collection at NIF

    International Nuclear Information System (INIS)

    Shaughnessy, D.A.; Moody, K.J.; Grant, P.M.; Lewis, L.A.; Hutcheon, I.D.; Lindvall, R.; Gostic, J.M.

    2011-01-01

    through the use of a part meant to be replaced regularly. The solid angle covered by one of the shields is roughly 10 -4 of 4π. If several shields were analyzed at once, it would increase the solid angle of the collection area accordingly. The glass shields consist of ammonia hardened silica with a sol gel coating and kapton tape around the edge. The square sheets are 14-inch on each side. The original shields were 1 mm thick, but it was determined that a thicker shield (3.3 mm) was more effective in preventing debris from reaching the FOA. The Solid Radchem group received two sets of DDS as part of our evaluation of the potential use of the DDS as solid debris collectors. The first set consisted of two 3.3 mm shields, one each from the top and bottom of the chamber (the '3mm set'). The second set consisted of four 1mm shields, one from the top of the chamber and the other three from the bottom (the 'IFSA set'). For each set, the shields were cut into smaller subsamples, which were then imaged using scanning electron microscopy (SEM) followed by chemical leaching and mass spectrometry. The purpose was to evaluate both the quantity and identity of the debris that was present on the DDS surfaces, and to determine if any of the capsule debris was reaching the chamber walls. In addition, potential enhancement due to gravity in the chamber was evaluated by directly comparing shields fielded in the top and bottom of the chamber. Based on the results, the use of the DDS as debris collectors would be evaluated. The results from both sets were presented to the DDS Working Group. The slides are attached to this document. The 3mm set results are presented first, followed by the results from the IFSA set. In both cases it was determined that a small fraction of the overall debris field was collected on the DDS. This means that the debris that is formed during a NIF shot is condensing out of the plasma and depositing on surfaces closer to the target chamber center, or else it is

  19. Age and Stratigraphic Relationships in Massif-Debris-Apron Terrain in Western Phlegra Montes, Mars

    Science.gov (United States)

    Kress, A.; Head, J. W.; Safaeinili, A.; Holt, J.; Plaut, J.; Posiolova, L.; Phillips, R.; Seu, R.; Sharad Team

    2010-03-01

    SHARAD returns from lobate debris aprons (LDA) near Phlegra Montes may show similarly high ice contents to other LDA on Mars; geomorphology and surface ages of the deposits confirm this detection and support a debris-covered-glacier origin for LDA.

  20. Burden of volcanic dust and nuclear debris after injection into the stratosphere at 40 degree to 58 degree N

    International Nuclear Information System (INIS)

    Volz, F.E.

    1975-01-01

    Meridional profiles of turbidity at some periods after the explosion of Katmai volcano in June 1912 at 58degreeN are compared with debris burden from Chinese nuclear tests. Katmai turbidity was previously obtained from solar radiation data, and debris burden was calculated from published mixing ratio data. Turbidity and burden generally peak strongly in arctic latitudes. Only two tests show indications of a bulge at 30degree-45degreeN which probably existed for Katmai dust in spring 1913. The residence time of Katmai dust was found to have been about 1 year, whereas fallout of nuclear debris seems not to have started before the winter following the tests. For September 1912 the total amount of Katmai aerosol is estimated to have been 13 million metric tons. Analogies to predicted meridional distribution of SST pollutants are being mentioned

  1. Burden of volcanic dust and nuclear debris after injection into the stratosphere at 400 to 580N

    International Nuclear Information System (INIS)

    Volz, F.E.

    1975-01-01

    Meridional profiles of turbidity at some periods after the explosion of Katmai volcano in June 1912 at 58 0 N are compared with debris burden from Chinese nuclear tests. Katmai turbidity was previously obtained from solar radiation data, and debris burden was calculated from published mixing ratio data. Turbidity and burden generally peak strongly in arctic latitudes. Only two tests show indications of a bulge at 30 0 --45 0 N which probably existed for Katmai dust in spring 1913. The residence time of Katmai dust was found to have been about 1 year, whereas fallout of nuclear debris seems not to have started before the winter following the tests. For September 1912 the total amount of Katmai aerosol is estimated to have been 13 million metric tons. Analogies to predicted meridional distribution of SST pollutants are being mentioned

  2. Plastic debris retention and exportation by a mangrove forest patch

    International Nuclear Information System (INIS)

    Ivar do Sul, Juliana A.; Costa, Monica F.; Silva-Cavalcanti, Jacqueline S.; Araújo, Maria Christina B.

    2014-01-01

    Highlights: • Estuaries and mangrove forests are rarely studied for marine plastic debris loads. • Types of plastic items and mangrove forest habitats determine the potential of debris retention. • Mangrove habitats are temporary sinks of plastic debris from river and marine origins. • Plastics rapidly accumulate in mangrove forest, but are exported slowly. • Fauna and fishers using mangrove forest habitats are at risk of interaction with plastic debris. -- Abstract: An experiment observed the behavior of selected tagged plastic items deliberately released in different habitats of a tropical mangrove forest in NE Brazil in late rainy (September) and late dry (March) seasons. Significant differences were not reported among seasons. However, marine debris retention varied among habitats, according to characteristics such as hydrodynamic (i.e., flow rates and volume transported) and relative vegetation (Rhizophora mangle) height and density. The highest grounds retained significantly more items when compared to the borders of the river and the tidal creek. Among the used tagged items, PET bottles were more observed and margarine tubs were less observed, being easily transported to adjacent habitats. Plastic bags were the items most retained near the releasing site. The balance between items retained and items lost was positive, demonstrating that mangrove forests tend to retain plastic marine debris for long periods (months-years)

  3. Problems of Small Debris

    Directory of Open Access Journals (Sweden)

    V. V. Zelentsov

    2015-01-01

    Full Text Available During the exploration of outer space (as of 1/1 2011 6853 was launched spacecraft (SC are successful 6264, representing 95% of the total number of starts. The most intensively exploited space Russia (USSR (3701 starts, 94% successful, USA (2774 starts, 90% successful, China (234 starts, 96% successful and India (89 starts, 90% successful. A small part of running the spacecraft returned to Earth (manned spacecraft and transport, and the rest remained in orbit. Some of them are descended from orbit and burned up in the atmosphere, the rest remained in the OCP and turned into space debris (SD.The composition of the Cabinet is diverse: finish the job spacecraft; boosters and the last stage of launch vehicles left in orbit after SC injection; technological waste arising during the opening drop-down structures and fragments of the destroyed spacecraft. The resulting explosion orbital SD forms ellipsoidal region which orbits blasted object. Then, as a result of precession, is the distribution of objects in orbit explosion exploding spacecraft.The whole Cabinet is divided into two factions: the observed (larger than 100 mm and not observed (less than 100 mm. Observed debris katalogalizirovan and 0.2% of the total number of SD, there was no SD is the bulk - 99.8%.SC meeting working with a fragment observed SD predictable and due to changes in altitude spacecraft avoids a possible meeting. Contact spacecraft with large fragment lead to disaster (which took place at a meeting of the Russian communications satellite "Cosmos-2251" and the American machine "Iridium". Meeting with small SD is not predictable, especially if it was formed by an explosion or collision fragments together. Orbit that KM is not predictable, and the speed can be up to 10 km / s. Meeting with small particle SD no less dangerous for the spacecraft. The impact speed of spacecraft with space debris particles can reach up to 10 ... 15 km / s at such speeds the breakdown probability thin

  4. Experimental study on coolability of particulate core-metal debris bed with oxidization, (2). Fragmentation and enhanced heat transfer in zircaloy debris bed

    International Nuclear Information System (INIS)

    Su, Guanghui; Sugiyama, Ken-ichiro; Aoki, Hiroomi; Kimura, Iichi

    2006-01-01

    The oxidization and coolability characteristics of the particulate Zircaloy debris bed, which is deposited under the hard debris and through which first vapor penetrates and then water penetrates, are studied in the present paper. In the vapor penetration experiments, it is found that Zircaloy debris particles are effectively broken into small pieces after making thick oxidized layer with deep clacks by rapid oxidization under the condition that vapor with 20 cm/s penetrates for 30 to 70 min at an initial debris bed temperature of 1,030degC. It is also confirmed in the water penetration experiments that the oxidized particle debris bed has potentially of high coolability when water penetrates through the fully oxidized particle bed because of a high capillary force originating from those particles with deep cracks on their surfaces. Based on the present study, a new scenario for the appearance and disappearance of the hot spot in the TMI-2 accident is possible. The particulate core-metal core-metal debris bed is first heated up by rapid oxidization with heat generation when vapor can penetrate through the debris bed with porosities. This corresponds to the appearance of the hot spot. The resultant oxidized particulate debris bed causes a high coolability due to its high capillary force when the water can touch the debris bed at wet condition. This corresponds to the disappearance of the hot spot. (author)

  5. Behaviour of Chernobyl fallout radionuclides deposited on peat and urban surfaces in Finland

    International Nuclear Information System (INIS)

    Reponen, A.

    1992-10-01

    In the thesis the impact of the Chernobyl nuclear reactor accident on Finland was studied in three aspects: (1) the areal distribution of Chernobyl fallout in Finland was determined by measuring peat samples, (2) the behaviour of fallout radionuclides was investigated in the combustion of peat in power plants, and (3) the removal rates of fallout radionuclides on urban surfaces were resolved

  6. MOLECULAR GAS IN YOUNG DEBRIS DISKS

    International Nuclear Information System (INIS)

    Moor, A.; Abraham, P.; Kiss, Cs.; Juhasz, A.; Kospal, A.; Pascucci, I.; Apai, D.; Henning, Th.; Csengeri, T.; Grady, C.

    2011-01-01

    Gas-rich primordial disks and tenuous gas-poor debris disks are usually considered as two distinct evolutionary phases of the circumstellar matter. Interestingly, the debris disk around the young main-sequence star 49 Ceti possesses a substantial amount of molecular gas and possibly represents the missing link between the two phases. Motivated to understand the evolution of the gas component in circumstellar disks via finding more 49 Ceti-like systems, we carried out a CO J = 3-2 survey with the Atacama Pathfinder EXperiment, targeting 20 infrared-luminous debris disks. These systems fill the gap between primordial and old tenuous debris disks in terms of fractional luminosity. Here we report on the discovery of a second 49 Ceti-like disk around the 30 Myr old A3-type star HD21997, a member of the Columba Association. This system was also detected in the CO(2-1) transition, and the reliable age determination makes it an even clearer example of an old gas-bearing disk than 49 Ceti. While the fractional luminosities of HD21997 and 49 Ceti are not particularly high, these objects seem to harbor the most extended disks within our sample. The double-peaked profiles of HD21997 were reproduced by a Keplerian disk model combined with the LIME radiative transfer code. Based on their similarities, 49 Ceti and HD21997 may be the first representatives of a so far undefined new class of relatively old (∼>8 Myr), gaseous dust disks. From our results, neither primordial origin nor steady secondary production from icy planetesimals can unequivocally explain the presence of CO gas in the disk of HD21997.

  7. Debris Flow Occurrence and Sediment Persistence, Upper Colorado River Valley, CO.

    Science.gov (United States)

    Grimsley, K J; Rathburn, S L; Friedman, J M; Mangano, J F

    2016-07-01

    Debris flow magnitudes and frequencies are compared across the Upper Colorado River valley to assess influences on debris flow occurrence and to evaluate valley geometry effects on sediment persistence. Dendrochronology, field mapping, and aerial photographic analysis are used to evaluate whether a 19th century earthen, water-conveyance ditch has altered the regime of debris flow occurrence in the Colorado River headwaters. Identifying any shifts in disturbance processes or changes in magnitudes and frequencies of occurrence is fundamental to establishing the historical range of variability (HRV) at the site. We found no substantial difference in frequency of debris flows cataloged at eleven sites of deposition between the east (8) and west (11) sides of the Colorado River valley over the last century, but four of the five largest debris flows originated on the west side of the valley in association with the earthen ditch, while the fifth is on a steep hillslope of hydrothermally altered rock on the east side. These results suggest that the ditch has altered the regime of debris flow activity in the Colorado River headwaters as compared to HRV by increasing the frequency of debris flows large enough to reach the Colorado River valley. Valley confinement is a dominant control on response to debris flows, influencing volumes of aggradation and persistence of debris flow deposits. Large, frequent debris flows, exceeding HRV, create persistent effects due to valley geometry and geomorphic setting conducive to sediment storage that are easily delineated by valley confinement ratios which are useful to land managers.

  8. Radioactive fall-out in Norway after the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Skjerve, Eystein [Dept. of Food Hygiene, Norwegian College of Veterinary Medicine (Norway)

    1986-07-01

    During the fall-out from the atmosphere during the fifties and sixties, a system of local control of radioactive contamination of food was built up. (LORACON - LOcal RAdioactivity COntrol). The different Meat and Food Inspection Services were equipped with Geiger Mueller instruments. The system was in operation until late seventies. From 1977 there was no testing and calibration of the instruments. The development towards a reduction of the state of readiness was accelerated when the Norwegian Parliament decided that Norway should not establish any nuclear power plants (1979). Only the universities and special institutions as the National Institute of Radiation Hygiene and the Institute for Energy Technique were still able to analyse on radioactive isotopes. The confusion about how much radioactive fall-out from the Chernobyl reactor accident Norway received lasted for some weeks in Norway. Partially, this was due to the lack of instruments, but also many experts rejected the idea that an accident so far away might cause these amounts of fall-out consisted of Iodine and Cesium. The fall-out followed a very irregular pattern both nationally and locally with the mountain areas in Middle Norway most affected.

  9. PROCIV, Protection Coefficient from Fallout in Residential Area Housing

    International Nuclear Information System (INIS)

    Warme-Janville, B.

    1983-01-01

    Description of problem or function: PROCIV calculates the protection coefficients against radioactive fallout for collective housing in a residential area. Each house is simulated by a cylindrical tower. The material thickness traversed by the photons is converted to an equivalent layer of air. The masking by neighbouring houses is taken into account

  10. Radioactive fallout from the Chernobyl nuclear reactor accident

    International Nuclear Information System (INIS)

    Beiriger, J.M.; Failor, R.A.; Marsh, K.V.; Shaw, G.E.

    1987-08-01

    This report describes the detection of fallout in the United States from the Chernobyl nuclear reactor accident. As part of its environmental surveillance program, Lawrence Livermore National Laboratory maintained detectors for gamma-emitting radionuclides. Following the reactor accident, additional air filters were set out. Several uncommon isotopes were detected at the time the plume passed into the US

  11. Radioactive fall-out in Norway after the Chernobyl accident

    International Nuclear Information System (INIS)

    Skjerve, Eystein

    1986-01-01

    During the fall-out from the atmosphere during the fifties and sixties, a system of local control of radioactive contamination of food was built up. (LORACON - LOcal RAdioactivity COntrol). The different Meat and Food Inspection Services were equipped with Geiger Mueller instruments. The system was in operation until late seventies. From 1977 there was no testing and calibration of the instruments. The development towards a reduction of the state of readiness was accelerated when the Norwegian Parliament decided that Norway should not establish any nuclear power plants (1979). Only the universities and special institutions as the National Institute of Radiation Hygiene and the Institute for Energy Technique were still able to analyse on radioactive isotopes. The confusion about how much radioactive fall-out from the Chernobyl reactor accident Norway received lasted for some weeks in Norway. Partially, this was due to the lack of instruments, but also many experts rejected the idea that an accident so far away might cause these amounts of fall-out consisted of Iodine and Cesium. The fall-out followed a very irregular pattern both nationally and locally with the mountain areas in Middle Norway most affected

  12. JSC Orbital Debris Website Description

    Science.gov (United States)

    Johnson, Nicholas L.

    2006-01-01

    Purpose: The website provides information about the NASA Orbital Debris Program Office at JSC, which is the lead NASA center for orbital debris research. It is recognized world-wide for its leadership in addressing orbital debris issues. The NASA Orbital Debris Program Office has taken the international lead in conducting measurements of the environment and in developing the technical consensus for adopting mitigation measures to protect users of the orbital environment. Work at the center continues with developing an improved understanding of the orbital debris environment and measures that can be taken to control its growth. Major Contents: Orbital Debris research is divided into the following five broad efforts. Each area of research contains specific information as follows: 1) Modeling - NASA scientists continue to develop and upgrade orbital debris models to describe and characterize the current and future debris environment. Evolutionary and engineering models are described in detail. Downloadable items include a document in PDF format and executable software. 2) Measurements - Measurements of near-Earth orbital debris are accomplished by conducting ground-based and space-based observations of the orbital debris environment. The data from these sources provide validation of the environment models and identify the presence of new sources. Radar, optical and surface examinations are described. External links to related topics are provided. 3) Protection - Orbital debris protection involves conducting hypervelocity impact measurements to assess the risk presented by orbital debris to operating spacecraft and developing new materials and new designs to provide better protection from the environment with less weight penalty. The data from this work provides the link between the environment defined by the models and the risk presented by that environment to operating spacecraft and provides recommendations on design and operations procedures to reduce the risk as

  13. Active Space Debris Removal System

    Directory of Open Access Journals (Sweden)

    Gabriele GUERRA

    2017-06-01

    Full Text Available Since the start of the space era, more than 5000 launches have been carried out, each carrying satellites for many disparate uses, such as Earth observation or communication. Thus, the space environment has become congested and the problem of space debris is now generating some concerns in the space community due to our long-lived belief that “space is big”. In the last few years, solutions to this problem have been proposed, one of those is Active Space Debris Removal: this method will reduce the increasing debris growth and permit future sustainable space activities. The main idea of the method proposed below is a drag augmentation system: use a system capable of putting an expanded foam on a debris which will increase the area-to-mass ratio to increase the natural atmospheric drag and solar pressure. The drag augmentation system proposed here requires a docking system; the debris will be pushed to its release height and then, after un-docking, an uncontrolled re-entry takes place ending with a burn up of the object and the foam in the atmosphere within a given time frame. The method requires an efficient way to change the orbit between two debris. The present paper analyses such a system in combination with an Electric Propulsion system, and emphasizes the choice of using two satellites to remove five effective rockets bodies debris within a year.

  14. TMI-2 core debris analysis

    International Nuclear Information System (INIS)

    Cook, B.A.; Carlson, E.R.

    1985-01-01

    One of the ongoing examination tasks for the damaged TMI-2 reactor is analysis of samples of debris obtained from the debris bed presently at the top of the core. This paper summarizes the results reported in the TMI-2 Core Debris Grab Sample Examination and Analysis Report, which will be available early in 1986. The sampling and analysis procedures are presented, and information is provided on the key results as they relate to the present core condition, peak temperatures during the transient, temperature history, chemical interactions, and core relocation. The results are then summarized

  15. Space Debris Mitigation CONOPS Development

    Science.gov (United States)

    2013-06-01

    literature search and review a lone article was found with any discussion of it. As with any net, the concept is to catch space debris objects in the net...travel along the track of the orbit and collect debris along its path. The lone article found contends that the idea “does not work”. Bonnal and...100,000 pieces of debris orbiting the planet , [as] NASA estimated -- 2,600 of them more than [four] inches across. [NASA] called the breakup of the

  16. Vertical soil migration of radionuclide fallout from the Chernobyl' accident

    International Nuclear Information System (INIS)

    Silant'ev, A.N.; Shkuratova, I.G.; Bobovnikova, T.I.

    1989-01-01

    The most suitable model for describing the behavior of radionuclide fallout on a soil surface is quasidiffusion transfer with directional transfer taken into account. The parameter values for this have been determined previously and are supplemented by the results of this work. To investigate the initial radionuclide distribution along the soil profile, monolithic soil samples 5 cm thick were taken in June-September 1986 in areas which had been subjected to contamination due to the Chernobyl' accident. The samples taken were cut up into layers. The first layer, 0.5 cm thick, was cut off from the surface of the soil monolith together with the grass. The next layer cut off was also 0.5 cm thick. Then two layers, each 1 cm in thickness, were cut off. The thickness of the last layer was 2 cm. The vertical distribution of radionuclides along the soil profile which was examined may be called the initial distribution, which will then change due to nonimmediate migration of radionuclides in the soil. Based on the research which has been performed, the following conclusions may be drawn. One portion of the radionuclides resulting from fallout is trapped by plant cover, while the other enters immediately into the soil. For a thick plant covering, about 80% of the radionuclide fallout is sorbed by the grass; for sparse cover, about 40%. The radionuclides entering the soil along with rainwater penetrate into the soil depths, producing contamination which falls off exponentially with depth. The exponent index is close to 1 cm -1 . In a forest, the main amount of radionuclide fallout is trapped by litter. Approximately 10% of the contamination fallout penetrates beneath the litter

  17. The coefficients of the damping in the radioactive fall-out

    International Nuclear Information System (INIS)

    Stofanova, N.; Usacev, S.

    1977-01-01

    Radioactive fallout is characterized by time and seasonal variations. So far the independent growth of mysimum 3 H, 90 Sr and 14 C fallout has been followed. The maxima and minima of the total fallout were compared with the above-mentioned isotopes. By introducing monthly, seasonal and annual damping coefficients, it was possible to determine the time difference of the maxima of the fallout for the individual components, namely 3 H, 90 Sr and 14 C. By calculating the coefficients, graphs were compiled showing the difference in the maxima of the summation β activities for the years 1959 to 1973 and the difference of the said components of fallout. (author)

  18. Medical status of Marshallese accidentally exposed to 1954 Bravo fallout radiation: January 1980-December 1982

    International Nuclear Information System (INIS)

    Adams, W.H.; Harper, J.A.; Rittmaster, R.S.; Heotis, P.M.; Scott, W.A.

    1984-01-01

    This report updates, for 1980 through 1982, the results of continuing medical surveillance of a Marshallese population accidentally exposed to radioactive fallout in March 1954. The originally exposed Marshallese population comprised 64 persons on Rongelap Atoll who each received, on the average, an estimated 190 rads of absorbed external gamma radiation, 18 on Ailingnae Atoll who received 110 rads, and 159 on Utirik who received 11 rads. There were, in addition, 3 persons in utero on Rongelap, 1 person in utero on Ailingnae, and 8 persons in utero on Utirik who are considered exposed. The recipients of primary medical care include exposed and comparison populations as well as a rather large number of additional beneficiaries who are seen on a humanitarian basis of practical need and resource availability. In recent years, about 1400 people have been seen annually. This report, however, deals with four clearly defined groups: the remaining individuals who were exposed to radioactive fallout on Rongelap, Ailingnae, and Utirik in 1954 (including those in utero), and a comparison population of individuals from Rongelap who were unexposed. The number of persons now in each exposure category are 51, 12, 116, and 137, respectively. 100 references, 4 figures, 5 tables

  19. Medical status of Marshallese accidentally exposed to 1954 Bravo fallout radiation: January 1980-December 1982

    Energy Technology Data Exchange (ETDEWEB)

    Adams, W.H.; Harper, J.A.; Rittmaster, R.S.; Heotis, P.M.; Scott, W.A.

    1984-01-01

    This report updates, for 1980 through 1982, the results of continuing medical surveillance of a Marshallese population accidentally exposed to radioactive fallout in March 1954. The originally exposed Marshallese population comprised 64 persons on Rongelap Atoll who each received, on the average, an estimated 190 rads of absorbed external gamma radiation, 18 on Ailingnae Atoll who received 110 rads, and 159 on Utirik who received 11 rads. There were, in addition, 3 persons in utero on Rongelap, 1 person in utero on Ailingnae, and 8 persons in utero on Utirik who are considered exposed. The recipients of primary medical care include exposed and comparison populations as well as a rather large number of additional beneficiaries who are seen on a humanitarian basis of practical need and resource availability. In recent years, about 1400 people have been seen annually. This report, however, deals with four clearly defined groups: the remaining individuals who were exposed to radioactive fallout on Rongelap, Ailingnae, and Utirik in 1954 (including those in utero), and a comparison population of individuals from Rongelap who were unexposed. The number of persons now in each exposure category are 51, 12, 116, and 137, respectively. 100 references, 4 figures, 5 tables. (ACR)

  20. NASA Orbital Debris Baseline Populations

    Science.gov (United States)

    Krisko, Paula H.; Vavrin, A. B.

    2013-01-01

    The NASA Orbital Debris Program Office has created high fidelity populations of the debris environment. The populations include objects of 1 cm and larger in Low Earth Orbit through Geosynchronous Transfer Orbit. They were designed for the purpose of assisting debris researchers and sensor developers in planning and testing. This environment is derived directly from the newest ORDEM model populations which include a background derived from LEGEND, as well as specific events such as the Chinese ASAT test, the Iridium 33/Cosmos 2251 accidental collision, the RORSAT sodium-potassium droplet releases, and other miscellaneous events. It is the most realistic ODPO debris population to date. In this paper we present the populations in chart form. We describe derivations of the background population and the specific populations added on. We validate our 1 cm and larger Low Earth Orbit population against SSN, Haystack, and HAX radar measurements.

  1. DebriSat Laboratory Analyses

    Science.gov (United States)

    2015-01-05

    droplets. Fluorine from Teflon wire insulation was also common in the SEM stub and witness plates deposits. Nano droplets of metallic materials...and Debris-LV debris. Aluminum was from the Al honeycomb, nadir and zenith panels, structural core and COPV liner. Aluminum oxide particles were...three pieces: Outer Nylon shell (sabot) with 2 part hollow aluminum insert. • ~600 grams, 8.6 cm diameter X 10.3 cm long – size of a soup can

  2. Backwater development by woody debris

    Science.gov (United States)

    Geertsema, Tjitske; Torfs, Paul; Teuling, Ryan; Hoitink, Ton

    2017-04-01

    Placement of woody debris is a common method for increasing ecological values in river and stream restoration, and is thus widely used in natural environments. Water managers, however, are afraid to introduce wood in channels draining agricultural and urban areas. Upstream, it may create backwater, depending on hydrodynamic characteristics including the obstruction ratio, the Froude number and the surface level gradient. Patches of wood may trigger or counter morphological activity, both laterally, through bank erosion and protection, and vertically, with pool and riffle formation. Also, a permeable construction composed of wood will weather over time. Both morphodynamic activity and weathering cause backwater effects to change in time. The purpose of this study is to quantify the time development of backwater effects caused by woody debris. Hourly water levels gauged upstream and downstream of patches and discharge are collected for five streams in the Netherlands. The water level drop over the woody debris patch relates to discharge in the streams. This relation is characterized by an increasing water level difference for an increasing discharge, up to a maximum. If the discharge increases beyond this level, the water level difference reduces to the value that may represent the situation without woody debris. This reduction depends primarily on the obstruction ratio of the woody debris in the channel cross-section. Morphologic adjustments in the stream and reorientation of the woody material reduce the water level drop over the patches in time. Our results demonstrate that backwater effects can be reduced by optimizing the location where woody debris is placed and manipulating the obstruction ratio. Current efforts are focussed on representing woody debris in a one-dimensional numerical model, aiming to obtain a generic tool to achieve a stream design with woody debris that minimizes backwater.

  3. Debris Disks: Probing Planet Formation

    OpenAIRE

    Wyatt, Mark C.

    2018-01-01

    Debris disks are the dust disks found around ~20% of nearby main sequence stars in far-IR surveys. They can be considered as descendants of protoplanetary disks or components of planetary systems, providing valuable information on circumstellar disk evolution and the outcome of planet formation. The debris disk population can be explained by the steady collisional erosion of planetesimal belts; population models constrain where (10-100au) and in what quantity (>1Mearth) planetesimals (>10km i...

  4. An Ontological Architecture for Orbital Debris Data

    OpenAIRE

    Rovetto, Robert J.

    2017-01-01

    The orbital debris problem presents an opportunity for inter-agency and international cooperation toward the mutually beneficial goals of debris prevention, mitigation, remediation, and improved space situational awareness (SSA). Achieving these goals requires sharing orbital debris and other SSA data. Toward this, I present an ontological architecture for the orbital debris domain, taking steps in the creation of an orbital debris ontology (ODO). The purpose of this ontological system is to ...

  5. New advances for modelling the debris avalanches

    Science.gov (United States)

    Cuomo, Sabatino; Cascini, Leonardo; Pastor, Manuel; Castorino, Giuseppe Claudio

    2013-04-01

    Flow-like landslides are a major global hazard and they occur worldwide causing a large number of casualties, significant structural damages to property and infrastructures as well as economic losses. When involving open slopes, these landslides often occur in triangular source areas where initial slides turn into avalanches through further failures and/or eventual soil entrainment. This paper deals with the numerical modelling of the propagation stage of debris avalanches which provides information such as the propagation pattern of the mobilized material, its velocity, thickness and run-out distance. In the paper, a "depth integrated" model is used which allows: i) adequately taking into account the irregular topography of real slopes which greatly affect the propagation stage and ii) using a less time consuming model than fully 3D approaches. The used model is named "GeoFlow_SPH" and it was formerly applied to theoretical, experimental and real case histories (Pastor et al., 2009; Cascini et al., 2012). In this work the behavior of debris avalanches is analyzed with special emphasis on the apical angle, one of the main features of this type of landslide, in relation to soil rheology, hillslope geometry and features of triggering area. Furthermore, the role of erosion has been investigated with reference to the uppermost parts of open slopes with a different steepness. These analyses are firstly carried out for simplified benchmark slopes, using both water-like materials (with no shear strength) and debris type materials. Then, three important case studies of Campania region (Cervinara, Nocera Inferiore e Sarno) are analyzed where debris avalanches involved pyroclastic soils originated from the eruptive products of Vesusius volcano. The results achieved for both benchmark slopes and real case histories outline the key role played by the erosion on the whole propagation stage of debris avalanches. The results are particularly satisfactory since they indicate the

  6. Overview of the National Cancer Institute's activities related to exposure of the public to fallout from the Nevada Test Site

    International Nuclear Information System (INIS)

    Wachholz, B.W.

    1990-01-01

    The Department of Health and Human Services (DHHS) was directed by Congress to assess the risk of thyroid cancer from 131I associated with fallout from the atmospheric testing of nuclear weapons at the Nevada Test Site. The National Cancer Institute (NCI) was requested by DHHS to address Public Law 97-414, Section 7 (a), which directs DHHS to (1) conduct scientific research and prepare analyses necessary to develop valid and credible assessments of the risks of thyroid cancer that are associated with thyroid doses of Iodine 131; (2)...develop...methods to estimate the thyroid doses of Iodine 131 that are received by individuals from nuclear bomb fallout; (and) (3)...develop...assessments of the exposure to Iodine 131 that the American people received from the Nevada atmospheric nuclear bomb tests. In addition, the University of Utah, under contract with the NCI, is carrying out a study to determine if the incidence of thyroid disease and leukemia among identified populations in Utah may be related to exposure from fallout originating at the Nevada Test Site

  7. Measurements of atmospheric fallout in Argentina; Determinacion del fallout atmosferico en la Republica Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Canoba, A C; Lopez, F O; Bruno, H A

    1998-11-01

    With the purpose of studying the radioactive fallout present in Argentina from atmospheric nuclear explosions tests that have been conducted recently, an environmental monitoring program, outside the influence of nuclear facilities of Argentina, was undertaken during 1996 and 1997. The levels of Cs-137 and Sr-90 were analysed in samples of air, deposited material (rainwater), milk, an average meal of a standard man and food. During this period, a total of 630 radiochemical analysis were performed on 325 samples of the different matrices described. The concentration levels of the radionuclides analysed in the different environmental matrices are presented and are compared with the values obtained in the environmental monitoring program done during the period 1960-1981. (author) 3 refs., 9 tabs. [Espanol] Con el proposito de estudiar la precipitacion radiactiva presente en la Republica Argentina, debido al ensayo de armas nucleares en la atmosfera realizadas en el pasado, se implemento el muestreo ambiental fuera de la zona de influencia de las instalaciones nucleares de la Argentina durante los anios 1996 y 1997. Se determinaron las concentraciones de cesio 137 y estroncio 90 en muestras de aire, deposito de material radiactivo (agua de lluvia), leche, dieta promedio de un individuo estandar y en alimentos varios. Se realizaron, durante el periodo mencionado, un total de 630 determinaciones radioquimicas sobre 325 muestras de las diferentes matrices mencionadas. Se presentan los niveles de concentracion de los radionucleidos analizados en las distintas matrices ambientales y se comparan los valores obtenidos en los monitoreos realizados durante el periodo 1960-1981. (autor)

  8. An estimate by two methods of thyroid absorbed doses due to BRAVO fallout in several Northern Marshall Islands.

    Science.gov (United States)

    Musolino, S V; Greenhouse, N A; Hull, A P

    1997-10-01

    Estimates of the thyroid absorbed doses due to fallout originating from the 1 March 1954 BRAVO thermonuclear test on Bikini Atoll have been made for several inhabited locations in the Northern Marshall Islands. Rongelap, Utirik, Rongerik and Ailinginae Atolls were also inhabited on 1 March 1954, where retrospective thyroid absorbed doses have previously been reconstructed. The current estimates are based primarily on external exposure data, which were recorded shortly after each nuclear test in the Castle Series, and secondarily on soil concentrations of 137Cs in samples collected in 1978 and 1988, along with aerial monitoring done in 1978. The external exposures and 137Cs soil concentrations were representative of the atmospheric transport and deposition patterns of the entire Castle Series tests and show that the BRAVO test was the major contributor to fallout exposure during the Castle series and other test series which were carried out in the Marshall Islands. These data have been used as surrogates for fission product radioiodines and telluriums in order to estimate the range of thyroid absorbed doses that may have occurred throughout the Marshall Islands. Dosimetry based on these two sets of estimates agreed within a factor of 4 at the locations where BRAVO was the dominant contributor to the total exposure and deposition. Both methods indicate that thyroid absorbed doses in the range of 1 Gy (100 rad) may have been incurred in some of the northern locations, whereas the doses at southern locations did not significantly exceed levels comparable to those from worldwide fallout. The results of these estimates indicate that a systematic medical survey for thyroid disease should be conducted, and that a more definitive dose reconstruction should be made for all the populated atolls and islands in the Northern Marshall Islands beyond Rongelap, Utirik, Rongerik and Ailinginae, which were significantly contaminated by BRAVO fallout.

  9. An estimate by two methods of thyroid absorbed doses due to BRAVO fallout in several northern Marshall Islands

    International Nuclear Information System (INIS)

    Musolino, S.V.; Hull, A.P.; Greenhouse, N.A.

    1997-01-01

    Estimates of the thyroid absorbed doses due to fallout originating from the 1 March 1954 BRAVO thermonuclear test on Bikini Atoll have been made for several inhabited locations in the Northern Marshall Islands. Rongelap, Utirik, Rongerik and Ailinginae Atolls were also inhabited on 1 March 1954, where retrospective thyroid absorbed doses have previously been reconstructed. Current estimates are based primarily on external exposure data, which were recorded shortly after each nuclear test in the Castle Series, and secondarily on soil concentrations of 137 Cs in samples collected in 1978 and 1988, along with aerial monitoring done in 1978. External exposures and 137 Cs Soil concentrations were representative of the atmospheric transport and deposition patterns of the entire Castle Series tests and show that the BRAVO test was the major contributor to fallout exposure during the Castle series and other test series which were carried out in the Marshall Islands. These data have been used as surrogates for fission product radioiodines and telluriums in order to estimate the range of thyroid absorbed doses that may have occurred throughout the Marshall Islands. Dosimetry based on these two sets of estimates agreed within a factor of 4 at the locations where BRAVO was the dominant contributor to the total exposure and deposition. Both methods indicate that thyroid absorbed doses in the range of 1 Gy (100 rad) may have been incurred in some of the northern locations, whereas the doses at southern locations did not significantly exceed levels comparable to those from worldwide fallout. The results of these estimates indicate that a systematic medical survey for thyroid disease should be conducted, and that a more definitive dose reconstruction should be made for all the populated atolls and islands in the Northern Marshall Islands beyond Rongelap, Utirik, Rongerik and Ailinginae, which were significantly contaminated by BRAVO fallout. 30 refs., 2 figs., 10 tabs

  10. Mechanics of debris flows and rock avalanches: Chapter 43

    Science.gov (United States)

    Iverson, Richard M.; Fernando, Harindra Joseph

    2012-01-01

    Debris flows are geophysical phenomena intermediate in character between rock avalanches and flash floods. They commonly originate as water-laden landslides on steep slopes and transform into liquefied masses of fragmented rock, muddy water, and entrained organic matter that disgorge from canyons onto valley floors. Typically including 50%–70% solid grains by volume, attaining speeds >10 m/s, and ranging in size up to ∼109 m3, debris flows can denude mountainsides, inundate floodplains, and devastate people and property (Figure 43.1). Notable recent debris-flow disasters resulted in more than 20,000 fatalities in Armero, Colombia, in 1985 and in Vargas state, Venezuela, in 1999.

  11. Radioactive fallout nuclides in a peat-bog ecosystem

    International Nuclear Information System (INIS)

    Pausch, G.; Hofmann, W.; Steger, F.; Tuerk, R.

    1996-01-01

    The Province of Salzburg belongs to the regions with the highest contamination from the Chernobyl-fallout outside the former USSR. The peat-bog investigated in this study is situated in Koppl, east of Salzburg. A peat-bog is a special example of an ecosystem, which is generally not disturbed by human activities because it is under strict nature-conservation and whose soil structure is not affected by animal activities from moles and earthworms. Peat-bogs are characterized by acidic soils which are high in organic material and low in clay mineral content. A number of previous studies have demonstrated that especially in peat-bogs and especially in the Koppl-peat-bog very high amounts of radioactive fallout nuclides from the Chernobyl accident and from the bomb-testings could be found

  12. An aerial radiological survey of the Trinity Fallout Area

    International Nuclear Information System (INIS)

    Fritzsche, A.E.

    1994-09-01

    An aerial gamma survey was conducted during May and June of 1992 to define the Trinity fallout field, which lies primarily in the White Sands Missile Range in the state of New Mexico. The field was mapped almost entirely from the gamma ray emissions of cesium-137 ( 137 Cs), a fission product. The field, as measured, extends from Trinity ground zero, over the Oscura Mountains, across the Chupadera Mesa, and thence past Cedarvale, New Mexico, a distance of more than 100 kilometers. An estimate of 137 Cs activity inventory is 100 Ci in an area covering 1,400 square kilometers. Another isotope, europium-152, is significant at ground zero. A 137 Cs concentration contour plot overlaid on a U.S. Geological Survey map indicates the location and intensity of the fallout field. A contour map of terrestrial exposure rate is presented in a similar fashion

  13. Airborne fallout mapping of 137Cs Finnish defence forces team

    International Nuclear Information System (INIS)

    Kettunen, M.; Heininen, T.; Pulakka, M.

    1997-01-01

    The main task of the team was to create a fallout map of 137 Cs in a specified area in Padasjoki Auttoinen village. The team used an MI-8 helicopter of the Finnish Air Force. The team had an HPGe system (relative efficiency 70%) to measure nuclide specific ground contamination level. For navigation the team took advantage of the DGPS service provided by Finnish Broadcasting company utilizing the RDS-channel to get position accuracy within 2 meters. The correction signal is reachable nationwide on the FM transmitter network. The system produced a distribution map for 40 K and fallout maps for 134,137 Cs using a Micro Station Program with TerraModeler application. The maximum measured 137 Cs ground contamination exceeded 130-140 kBqm -2 . (au)

  14. The origins of Technetium in the environment

    International Nuclear Information System (INIS)

    Scoppa, P.

    1986-01-01

    The origins of Technetium in the environment are briefly illustrated, taking into account its main sources represented by same plants of nuclear fuel cycle and by fallout fallowing nuclear explosion in atmosphere. An evaluation is also made of the TC-99 quantitees deriving from the production of nuclear power present in radioactive wastes before their final disposal

  15. MIPS Observations of the Fabulous Four Debris Disks

    Science.gov (United States)

    Su, K. Y. L.; Stansberry, J. A.; Rieke, G. H.; Trilling, D. E.; Stapelfeldt, K. R.; Werner, M. W.; Beichman, C.; Chen, C.; Marengo, M.; Megeath, T.; Backman, D.; van Cleve, J.

    2004-12-01

    The Multiband Imaging Photometer for Spitzer (MIPS) provides long-wavelength capability with imaging bands at 24, 70, and 160 um. We will present the MIPS images of the Fabulous Four Debris Disks: Beta Pictoris (A5 V), Epsilon Eridani (K2 V), Fomalhaut (A3 V) and Vega (A0 V). These systems discovered by IRAS possess large far-infrared excess emission above photosphere, indicating the existence of a circumstellar dusty disk. Given the main-sequence ages of these stars ( ˜12 Myr for Beta Pictoris, ˜730 Myr for Epsilon Eridani, ˜200 Myr for Fomalhaut, and ˜350 Myr for Vega), the dust in the systems could not be primordial as it would have been removed by radiation pressure and Poynting-Robertson drag on relatively short time scales ( ˜1E4 yr). The second-generation dust in such debris disks is thought to arise primarily from collisions between planetesimals (asteroids) and from cometary activity; however, details about the debris formation and evolution are not well understood. With the sensitivity and angular resolution of the Spitizer Space Telescope, the structures of these nearby debris disks were mapped in great detail to study the disks' spatial structures at mid- to far-infrared wavelengths. These high spatial resolution images provide unprecedented new constraints on the the dust properties in the systems and limits on the origin of dusty debris. Support for this work was provided by NASA through Contract Number 960785 issued by JPL/Caltech.

  16. Thyroid neoplasia in Marshall Islanders exposed to nuclear fallout

    International Nuclear Information System (INIS)

    Hamilton, T.E.; van Belle, G.; LoGerfo, J.P.

    1987-01-01

    We studied the risk of thyroid neoplasia in Marshall Islanders exposed to radioiodines in nuclear fallout from the 1954 BRAVO thermonuclear test. We screened 7266 Marshall Islanders for thyroid nodules; the islanders were from 14 atolls, including several southern atolls, which were the source of the best available unexposed comparison group. Using a retrospective cohort design, we determined the prevalence of thyroid nodularity in a subgroup of 2273 persons who were alive in 1954 and who therefore were potentially exposed to fallout from the BRAVO test. For those 12 atolls previously thought to be unexposed to fallout, the prevalence of thyroid nodules ranged from 0.9% to 10.6%. Using the distance of each atoll from the test site as a proxy for the radiation dose to the thyroid gland, a weighted linear regression showed an inverse linear relationship between distance and the age-adjusted prevalence of thyroid nodules. Distance was the strongest single predictor in logistic regression analysis. A new absolute risk estimate was calculated to be 1100 excess cases/Gy/y/1 X 10(6) persons (11.0 excess cases/rad/y/1 million persons), 33% higher than previous estimates. We conclude that an excess of thyroid nodules was not limited only to the two northern atolls but extended throughout the northern atolls; this suggests a linear dose-response relationship

  17. Global deposition of fallout radionuclides and their dietary intake

    International Nuclear Information System (INIS)

    Morisawa, Shinsuke

    1993-01-01

    Japanese foods depend largely on foreign countries and domestic food supply now is no more than 30 percents if feedstuffs for live-stocks are included. Therefore not only ecological/natural but also social, e.g., human activities related, transportation of fallout radionuclides are to be taken into accounts for estimation of baseline internal irradiation dose and health risks of Japanese peoples through dietary intake of radionuclides. In this study, mathematical model is developed and examined for practical application on estimating Japanese dietary intake level of fallout strontium-90, which is accumulated in various kinds of foodstuffs and is transported to Japan associated with worldwide trades of foods, under appropriate limitations such that direct deposition on plants and seafood intake pathways are not evaluated. Deposition of strontium-90 onto the surface soil was simulated using the model, the compartment model described by a set ordinary differential equations, and the estimates were examined by comparing them with the observed data colleted and complied by the global scale environmental monitoring networks. Sensitivity analysis is also practised to find possible reduction of dietary intake of fallout radionuclides and the related potential health risks. (author)

  18. Fallout and radiation doses in Norway after the Chernobyl accident

    International Nuclear Information System (INIS)

    Henriksen, T.

    1987-08-01

    Due to southeasterly wind and rainfall during the critical days after the Chernobyl accident, Norway got a substantial part of the cesium isotopes released. The radioactive fallout followed closely the rainfall and was mainly concentrated to some thin populated areas in the central parts of the country. The total fallout of the cesium isotopes was approximately 2300 TBq (Cs-137) and 1200 TBq (Cs-134). The average for the country was 11 kBq/m 2 with a variation from 1.5 to 40 kBq/m 2 for the 19 different counties of the country. The fallout resulted in contamination of food products from some areas, mainly meat from reindeer and sheep, as well as freshwater fish. A small fraction of the food produced in 1986 was not sold due to the regulations enforced. The average radiation dose to the Norwegian population during the first year after the accident was approximately 0.3 mSv (0.1 mSv from external radiation and about 0.2 mSv from foodstuff). This first year extra dose is approximately 5% of the average normal background dose in Norway

  19. Young Debris Disks With Newly Discovered Emission Features

    Science.gov (United States)

    Ballering, N.

    2014-04-01

    We analyzed the Spitzer/IRS spectra of young A and F stars that host debris disks with previously unidentified silicate emission features. Such features probe small, warm dust grains in the inner regions of these young systems where terrestrial planet formation may be proceeding (Lisse et al. 2009). For most systems, these regions are too near their host star to be directly seen with high-contrast imaging and too warm to be imaged with submillimeter interferometers. Mid-infrared excess spectra - originating from the thermal emission of the debris disk dust - remain the best data to constrain the properties of the debris in these regions. For each target, we fit physically-motivated model spectra to the data. Typical spectra of unresolved debris disks are featureless and suffer severe degeneracies between the dust location and the grain properties; however, spectra with solid-state emission features provide significantly more information, allowing for a more accurate determination of the dust size, composition, and location (e.g. Chen et al. 2006; Olofsson et al. 2012). Our results shed light on the dynamic properties occurring in the terrestrial regions of these systems. For instance, the sizes of the smallest grains and the nature of the grain size distribution reveal whether the dust originates from steady-state collisional cascades or from stochastic collisions. The properties of the dust grains - such as their crystalline or amorphous structure - can inform us of grain processing mechanisms in the disk. The location of this debris illuminates where terrestrial planet forming activity is occurring. We used results from the Beta Pictoris - which has a well-resolved debris disk with emission features (Li et al. 2012) - to place our results in context. References: Chen et al. 2006, ApJS, 166, 351 Li et al. 2012, ApJ, 759, 81 Lisse et al. 2009, ApJ, 701, 2019 Olofsson et al. 2012, A&A, 542, A90

  20. Application of simulation technique on debris flow hazard zone delineation: a case study in the Daniao tribe, Eastern Taiwan

    Directory of Open Access Journals (Sweden)

    M. P. Tsai

    2011-11-01

    Full Text Available Typhoon Morakot struck Taiwan in August 2009 and induced considerable disasters, including large-scale landslides and debris flows. One of these debris flows was experienced by the Daniao tribe in Taitung, Eastern Taiwan. The volume was in excess of 500 000 m3, which was substantially larger than the original design mitigation capacity. This study considered large-scale debris flow simulations in various volumes at the same area by using the DEBRIS-2D numerical program. The program uses the generalized Julien and Lan (1991 rheological model to simulate debris flows. In this paper, the sensitivity factor considered on the debris flow spreading is the amount of the debris flow initial volume. These simulated results in various amounts of debris flow initial volume demonstrated that maximal depths of debris flows were almost deposited in the same area, and also revealed that a 20% variation in estimating the amount of total volume at this particular site results in a 2.75% variation on the final front position. Because of the limited watershed terrain, the hazard zones of debris flows were not expanded. Therefore, the amount of the debris flow initial volume was not sensitive.

  1. Space debris mitigation - engineering strategies

    Science.gov (United States)

    Taylor, E.; Hammond, M.

    The problem of space debris pollution is acknowledged to be of growing concern by space agencies, leading to recent activities in the field of space debris mitigation. A review of the current (and near-future) mitigation guidelines, handbooks, standards and licensing procedures has identified a number of areas where further work is required. In order for space debris mitigation to be implemented in spacecraft manufacture and operation, the authors suggest that debris-related criteria need to become design parameters (following the same process as applied to reliability and radiation). To meet these parameters, spacecraft manufacturers and operators will need processes (supported by design tools and databases and implementation standards). A particular aspect of debris mitigation, as compared with conventional requirements (e.g. radiation and reliability) is the current and near-future national and international regulatory framework and associated liability aspects. A framework for these implementation standards is presented, in addition to results of in-house research and development on design tools and databases (including collision avoidance in GTO and SSTO and evaluation of failure criteria on composite and aluminium structures).

  2. Disaster Debris Recovery Database - Landfills

    Science.gov (United States)

    The US EPA Region 5 Disaster Debris Recovery Database includes public datasets of over 6,000 composting facilities, demolition contractors, transfer stations, landfills and recycling facilities for construction and demolition materials, electronics, household hazardous waste, metals, tires, and vehicles in the states of Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota, Missouri, North Dakota, Ohio, Pennsylvania, South Dakota, West Virginia and Wisconsin.In this update, facilities in the 7 states that border the EPA Region 5 states were added to assist interstate disaster debris management. Also, the datasets for composters, construction and demolition recyclers, demolition contractors, and metals recyclers were verified and source information added for each record using these sources: AGC, Biocycle, BMRA, CDRA, ISRI, NDA, USCC, FEMA Debris Removal Contractor Registry, EPA Facility Registry System, and State and local listings.

  3. Disaster Debris Recovery Database - Recovery

    Science.gov (United States)

    The US EPA Region 5 Disaster Debris Recovery Database includes public datasets of over 6,000 composting facilities, demolition contractors, transfer stations, landfills and recycling facilities for construction and demolition materials, electronics, household hazardous waste, metals, tires, and vehicles in the states of Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota, Missouri, North Dakota, Ohio, Pennsylvania, South Dakota, West Virginia and Wisconsin.In this update, facilities in the 7 states that border the EPA Region 5 states were added to assist interstate disaster debris management. Also, the datasets for composters, construction and demolition recyclers, demolition contractors, and metals recyclers were verified and source information added for each record using these sources: AGC, Biocycle, BMRA, CDRA, ISRI, NDA, USCC, FEMA Debris Removal Contractor Registry, EPA Facility Registry System, and State and local listings.

  4. Debris Flows and Related Phenomena

    Science.gov (United States)

    Ancey, C.

    Torrential floods are a major natural hazard, claiming thousands of lives and millions of dollars in lost property each year in almost all mountain areas on the Earth. After a catastrophic eruption of Mount St. Helen in the USA in May 1980, water from melting snow, torrential rains from the eruption cloud, and water displaced from Spirit Lake mixed with deposited ash and debris to produce very large debris flows and cause extensive damage and loss of life [1]. During the 1985 eruption of Nevado del Ruiz in Colombia, more than 20,000 people perished when a large debris flow triggered by the rapid melting of snow and ice at the volcano summit, swept through the town of Armero [2]. In 1991, the eruption of Pinatubo volcano in the Philippines disperses more than 5 cubic kilometres of volcanic ash into surrounding valleys. Much of that sediment has subsequently been mobilised as debris flows by typhoon rains and has devastated more than 300 square kilometres of agricultural land. Even, in Eur opean countries, recent events that torrential floods may have very destructive effects (Sarno and Quindici in southern Italy in May 1998, where approximately 200 people were killed). The catastrophic character of these floods in mountainous watersheds is a consequence of significant transport of materials associated with water flows. Two limiting flow regimes can be distinguished. Bed load and suspension refer to dilute transport of sediments within water. This means that water is the main agent in the flow dynamics and that the particle concentration does not exceed a few percent. Such flows are typically two-phase flows. In contrast, debris flows are mas s movements of concentrated slurries of water, fine solids, rocks and boulders. As a first approximation, debris flows can be treated as one-phase flows and their flow properties can be studied using classical rheological methods. The study of debris flows is a very exciting albeit immature science, made up of disparate elements

  5. A PRIMER ON UNIFYING DEBRIS DISK MORPHOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eve J.; Chiang, Eugene, E-mail: evelee@berkeley.edu, E-mail: echiang@astro.berkeley.edu [Department of Astronomy, University of California Berkeley, Berkeley, CA 94720-3411 (United States)

    2016-08-20

    A “minimum model” for debris disks consists of a narrow ring of parent bodies, secularly forced by a single planet on a possibly eccentric orbit, colliding to produce dust grains that are perturbed by stellar radiation pressure. We demonstrate how this minimum model can reproduce a wide variety of disk morphologies imaged in scattered starlight. Five broad categories of disk shape can be captured: “rings,” “needles,” “ships-and-wakes,” “bars,” and “moths (a.k.a. fans),” depending on the viewing geometry. Moths can also sport “double wings.” We explain the origin of morphological features from first principles, exploring the dependence on planet eccentricity, disk inclination dispersion, and the parent body orbital phases at which dust grains are born. A key determinant in disk appearance is the degree to which dust grain orbits are apsidally aligned. Our study of a simple steady-state (secularly relaxed) disk should serve as a reference for more detailed models tailored to individual systems. We use the intuition gained from our guidebook of disk morphologies to interpret, informally, the images of a number of real-world debris disks. These interpretations suggest that the farthest reaches of planetary systems are perturbed by eccentric planets, possibly just a few Earth masses each.

  6. A PRIMER ON UNIFYING DEBRIS DISK MORPHOLOGIES

    International Nuclear Information System (INIS)

    Lee, Eve J.; Chiang, Eugene

    2016-01-01

    A “minimum model” for debris disks consists of a narrow ring of parent bodies, secularly forced by a single planet on a possibly eccentric orbit, colliding to produce dust grains that are perturbed by stellar radiation pressure. We demonstrate how this minimum model can reproduce a wide variety of disk morphologies imaged in scattered starlight. Five broad categories of disk shape can be captured: “rings,” “needles,” “ships-and-wakes,” “bars,” and “moths (a.k.a. fans),” depending on the viewing geometry. Moths can also sport “double wings.” We explain the origin of morphological features from first principles, exploring the dependence on planet eccentricity, disk inclination dispersion, and the parent body orbital phases at which dust grains are born. A key determinant in disk appearance is the degree to which dust grain orbits are apsidally aligned. Our study of a simple steady-state (secularly relaxed) disk should serve as a reference for more detailed models tailored to individual systems. We use the intuition gained from our guidebook of disk morphologies to interpret, informally, the images of a number of real-world debris disks. These interpretations suggest that the farthest reaches of planetary systems are perturbed by eccentric planets, possibly just a few Earth masses each.

  7. A Primer on Unifying Debris Disk Morphologies

    Science.gov (United States)

    Lee, Eve J.; Chiang, Eugene

    2016-08-01

    A “minimum model” for debris disks consists of a narrow ring of parent bodies, secularly forced by a single planet on a possibly eccentric orbit, colliding to produce dust grains that are perturbed by stellar radiation pressure. We demonstrate how this minimum model can reproduce a wide variety of disk morphologies imaged in scattered starlight. Five broad categories of disk shape can be captured: “rings,” “needles,” “ships-and-wakes,” “bars,” and “moths (a.k.a. fans),” depending on the viewing geometry. Moths can also sport “double wings.” We explain the origin of morphological features from first principles, exploring the dependence on planet eccentricity, disk inclination dispersion, and the parent body orbital phases at which dust grains are born. A key determinant in disk appearance is the degree to which dust grain orbits are apsidally aligned. Our study of a simple steady-state (secularly relaxed) disk should serve as a reference for more detailed models tailored to individual systems. We use the intuition gained from our guidebook of disk morphologies to interpret, informally, the images of a number of real-world debris disks. These interpretations suggest that the farthest reaches of planetary systems are perturbed by eccentric planets, possibly just a few Earth masses each.

  8. Marine Debris Research, Prevention, and Reduction Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Marine Debris Research, Prevention, and Reduction Act legally establishes the National Oceanic and Atmospheric Administration's (NOAA) Marine Debris Program. The...

  9. The ecological impacts of marine debris

    NARCIS (Netherlands)

    Rochman, Chelsea M.; Browne, Mark Anthony; Underwood, A.J.; Franeker, Van Jan A.; Thompson, Richard C.; Amaral-Zettler, Linda A.

    2016-01-01

    Anthropogenic debris contaminates marine habitats globally, leading to several perceived ecological impacts. Here, we critically and systematically review the literature regarding impacts of debris from several scientific fields to understand the weight of evidence regarding the ecological

  10. Space Debris Elimination (SpaDE)

    Data.gov (United States)

    National Aeronautics and Space Administration — The amount of debris in low Earth orbit (LEO) has increased rapidly over the last twenty years. This prevalence of debris increases the likelihood of cascading...

  11. DebriSat Project Update and Planning

    Science.gov (United States)

    Sorge, M.; Krisko, P. H.

    2016-01-01

    DebriSat Reporting Topics: DebriSat Fragment Analysis Calendar; Near-term Fragment Extraction Strategy; Fragment Characterization and Database; HVI (High-Velocity Impact) Considerations; Requirements Document.

  12. History of plutonium composition of fallout in the northeastern U.S. from contemporary measurements

    International Nuclear Information System (INIS)

    Krey, P.W.; Heit, M.; Miller, K.M.; Livingston, H.D.

    1990-01-01

    The analyses of lake sediments from the northeastern US provide depositional histories of 137 Cs and 239+240 Pu from both global fallout and fallout from the Nevada Test Site detonations in the 1950's. These results provide an independent verification and extension of the temporal trend of the 240 Pu/ 239 Pu atom ratio of global fallout to earlier times. This data supports the findings of other studies of fallout in the atmospheric and marine environment. (author) 26 refs.; 8 figs.; 9 refs

  13. When the dust settles: stable xenon isotope constraints on the formation of nuclear fallout

    International Nuclear Information System (INIS)

    Cassata, W.S.; Prussin, S.G.; Knight, K.B.; Hutcheon, I.D.; Isselhardt, B.H.; Renne, P.R.

    2014-01-01

    Nuclear weapons represent one of the most immediate threats of mass destruction. In the event that a procured or developed nuclear weapon is detonated in a populated metropolitan area, timely and accurate nuclear forensic analysis and fallout modeling would be needed to support attribution efforts and hazard assessments. Here we demonstrate that fissiogenic xenon isotopes retained in radioactive fallout generated by a nuclear explosion provide unique constraints on (1) the timescale of fallout formation, (2) chemical fractionation that occurs when fission products and nuclear fuel are incorporated into fallout, and (3) the speciation of fission products in the fireball. Our data suggest that, in near surface nuclear tests, the presence of a significant quantity of metal in a device assembly, combined with a short time allowed for mixing with the ambient atmosphere (seconds), may prevent complete oxidation of fission products prior to their incorporation into fallout. Xenon isotopes thus provide a window into the chemical composition of the fireball in the seconds that follow a nuclear explosion, thereby improving our understanding of the physical and thermo-chemical conditions under which fallout forms. - Highlights: • Radioactive fallout generated by nuclear explosions contains fissiogenic xenon isotopes. • Xe isotopes provide constraints on timescales of fallout formation and the speciation of fission products in the fireball. • Our data indicate that macroscopic fallout forms rapidly (<3 s). • Chemical fractionation trends suggest that fission products may not have been fully oxidized prior to incorporation

  14. DebriSat Hypervelocity Impact Test

    Science.gov (United States)

    2015-08-01

    public release; distribution unlimited.  Targets: Scaled Multishock Shield, DebrisLV, and DebriSat  500-600 g hollow aluminum and nylon projectile... insulation . DebriSat’s internal components were structurally similar to real flight hardware but were nonfunctional. AEDC-TR-15-S-2 6...structures with an AL 5052 honeycomb core and M55J carbon fiber face sheets. The basic system characteristics of the DebriSat are given in Table 1

  15. Apically extruded dentin debris by reciprocating single-file and multi-file rotary system.

    Science.gov (United States)

    De-Deus, Gustavo; Neves, Aline; Silva, Emmanuel João; Mendonça, Thais Accorsi; Lourenço, Caroline; Calixto, Camila; Lima, Edson Jorge Moreira

    2015-03-01

    This study aims to evaluate the apical extrusion of debris by the two reciprocating single-file systems: WaveOne and Reciproc. Conventional multi-file rotary system was used as a reference for comparison. The hypotheses tested were (i) the reciprocating single-file systems extrude more than conventional multi-file rotary system and (ii) the reciprocating single-file systems extrude similar amounts of dentin debris. After solid selection criteria, 80 mesial roots of lower molars were included in the present study. The use of four different instrumentation techniques resulted in four groups (n = 20): G1 (hand-file technique), G2 (ProTaper), G3 (WaveOne), and G4 (Reciproc). The apparatus used to evaluate the collection of apically extruded debris was typical double-chamber collector. Statistical analysis was performed for multiple comparisons. No significant difference was found in the amount of the debris extruded between the two reciprocating systems. In contrast, conventional multi-file rotary system group extruded significantly more debris than both reciprocating groups. Hand instrumentation group extruded significantly more debris than all other groups. The present results yielded favorable input for both reciprocation single-file systems, inasmuch as they showed an improved control of apically extruded debris. Apical extrusion of debris has been studied extensively because of its clinical relevance, particularly since it may cause flare-ups, originated by the introduction of bacteria, pulpal tissue, and irrigating solutions into the periapical tissues.

  16. Drift simulation of MH370 debris using superensemble techniques

    Science.gov (United States)

    Jansen, Eric; Coppini, Giovanni; Pinardi, Nadia

    2016-07-01

    On 7 March 2014 (UTC), Malaysia Airlines flight 370 vanished without a trace. The aircraft is believed to have crashed in the southern Indian Ocean, but despite extensive search operations the location of the wreckage is still unknown. The first tangible evidence of the accident was discovered almost 17 months after the disappearance. On 29 July 2015, a small piece of the right wing of the aircraft was found washed up on the island of Réunion, approximately 4000 km from the assumed crash site. Since then a number of other parts have been found in Mozambique, South Africa and on Rodrigues Island. This paper presents a numerical simulation using high-resolution oceanographic and meteorological data to predict the movement of floating debris from the accident. Multiple model realisations are used with different starting locations and wind drag parameters. The model realisations are combined into a superensemble, adjusting the model weights to best represent the discovered debris. The superensemble is then used to predict the distribution of marine debris at various moments in time. This approach can be easily generalised to other drift simulations where observations are available to constrain unknown input parameters. The distribution at the time of the accident shows that the discovered debris most likely originated from the wide search area between 28 and 35° S. This partially overlaps with the current underwater search area, but extends further towards the north. Results at later times show that the most probable locations to discover washed-up debris are along the African east coast, especially in the area around Madagascar. The debris remaining at sea in 2016 is spread out over a wide area and its distribution changes only slowly.

  17. Photometric Studies of GEO Debris

    Science.gov (United States)

    Seitzer, Patrick; Cowardin, Heather M.; Barker, Edwin; Abercromby, Kira J.; Foreman, Gary; Horstman, Matt

    2009-01-01

    The photometric signature of a debris object can be useful in determining what the physical characteristics of a piece of debris are. We report on optical observations in multiple filters of debris at geosynchronous Earth orbit (GEO). Our sample is taken from GEO objects discovered in a survey with the University of Michigan's 0.6-m aperture Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the SMARTS (Small and Medium Aperture Research Telescope System) 0.9-m at CTIO for orbits and photometry. Our goal is to determine 6 parameter orbits and measure colors for all objects fainter than R = 15 th magnitude that are discovered in the MODEST survey. At this magnitude the distribution of observed angular rates changes significantly from that of brighter objects. There are two objectives: 1. Estimate the orbital distribution of objects selected on the basis of two observational criteria: brightness (magnitude) and angular rates. 2. Obtain magnitudes and colors in standard astronomical filters (BVRI) for comparison with reflectance spectra of likely spacecraft materials. What is the faint debris likely to be? In this paper we report on the photometric results. For a sample of 50 objects, more than 90 calibrated sequences of R-B-V-I-R magnitudes have been obtained with the CTIO 0.9-m. For objects that do not show large brightness variations, the colors are largely redder than solar in both B-R and R-I. The width of the color distribution may be intrinsic to the nature of the surfaces, but also could be that we are seeing irregularly shaped objects and measuring the colors at different times with just one telescope. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO 0.9-m observes in B, and MODEST in R. The CCD cameras are electronically linked together so that the start time and duration of observations are the same to better than 50 milliseconds. Thus

  18. Long-range tropospheric transport of uranium and plutonium weapons fallout from Semipalatinsk nuclear test site to Norway.

    Science.gov (United States)

    Wendel, Cato Christian; Fifield, L Keith; Oughton, Deborah H; Lind, Ole Christian; Skipperud, Lindis; Bartnicki, Jerzy; Tims, Stephen G; Høibråten, Steinar; Salbu, Brit

    2013-09-01

    A combination of state-of-the-art isotopic fingerprinting techniques and atmospheric transport modelling using real-time historical meteorological data has been used to demonstrate direct tropospheric transport of radioactive debris from specific nuclear detonations at the Semipalatinsk test site in Kazakhstan to Norway via large areas of Europe. A selection of archived air filters collected at ground level at 9 stations in Norway during the most intensive atmospheric nuclear weapon testing periods (1957-1958 and 1961-1962) has been screened for radioactive particles and analysed with respect to the concentrations and atom ratios of plutonium (Pu) and uranium (U) using accelerator mass spectrometry (AMS). Digital autoradiography screening demonstrated the presence of radioactive particles in the filters. Concentrations of (236)U (0.17-23nBqm(-3)) and (239+240)Pu (1.3-782μBqm(-3)) as well as the atom ratios (240)Pu/(239)Pu (0.0517-0.237) and (236)U/(239)Pu (0.0188-0.7) varied widely indicating several different sources. Filter samples from autumn and winter tended to have lower atom ratios than those sampled in spring and summer, and this likely reflects a tropospheric influence in months with little stratospheric fallout. Very high (236)U, (239+240)Pu and gross beta activity concentrations as well as low (240)Pu/(239)Pu (0.0517-0.077), (241)Pu/(239)Pu (0.00025-0.00062) and (236)U/(239)Pu (0.0188-0.046) atom ratios, characteristic of close-in and tropospheric fallout, were observed in filters collected at all stations in Nov 1962, 7-12days after three low-yield detonations at Semipalatinsk (Kazakhstan). Atmospheric transport modelling (NOAA HYSPLIT_4) using real-time meteorological data confirmed that long range transport of radionuclides, and possibly radioactive particles, from Semipalatinsk to Norway during this period was plausible. The present work shows that direct tropospheric transport of fallout from atmospheric nuclear detonations periodically may have

  19. Caesium fallout as a tracer of erosion-sedimentation

    International Nuclear Information System (INIS)

    Bouhlassa, S.; Azenfar, A.; Machrouh, A.

    1994-01-01

    The purpose of this paper is to set up a methodology of use of radioactive caesium fallout, to measure erosion and sedimentation in a sub-catchment and to establish the effects of geomorphological parameters, land uses and soil nature, on the losses caesium by physical process. The result obtained by this new and elegant approach, on a watershed of 4114 ha., studied before by classical and conventional techniques, gives a good evaluation of erosion, but also sedimentation rate, and permit to stand up, a model and sampling strategy, to extend the method to large catchment. 1 tab., 2 refs. (author)

  20. Radioactive fallout reconstruction from contemporary measurements of reservoir sediments

    International Nuclear Information System (INIS)

    Krey, P.W.; Heit, M.; Miller, K.M.

    1990-01-01

    The temporal history of atmospheric deposition to a watershed area can be preserved in the sediment of a lake or reservoir that is supplied by the watershed. The 137 Cs and isotopic Pu concentrations with depth were determined in the sediments of two reservoirs, Enterprise and Deer Creek, which are located in widely separated regions of the state of Utah. Our data not only reconstruct the history of the total radioactive fallout in the area, but also permit estimating the contributions from global sources and from the Nevada Test Site detonations in the 1950s

  1. Radioactive fallout in Norway from the Chernobyl accident

    International Nuclear Information System (INIS)

    Strand, P.

    1994-01-01

    The Chernobyl accident had considerable consequences for Norway. Except for the areas in the former USSR, around Chernobyl some areas in Norway received fallout which gave the highest contamination levels. The natural and semi natural ecosystems will produce food products with high activity levels of radiocesium for several decennium. Cost-effective countermeasures were implemented, and they reduced the doses considerable, especially for critical groups. Doses received over the next 50 years will probably cause cancer in 500 persons. 63 refs., 5 figs., 6 tabs

  2. Cesium fallout in Norway after the Chernobyl accident

    International Nuclear Information System (INIS)

    Backe, S.; Bjerke, H.; Rudjord, A.L.; Ugletveit, F.

    1986-01-01

    Results of country-wide measurements of 137 Cs and 134 Cs in soil samples in Norway after the Chernobyl accident are reported. The results clearly demonstrates that municipalities in the central part of southern Norway, Troendelag and the southern part of Nordland, have been rather heavily contaminated. The total fallout of 137 Cs and 134 Cs from the Chernobyl accident in Norway is estimated to 2300 TBq and 1200 TBq, respectively. This is approximately 6% of the cesium activity released from the reactor

  3. A fall-out shelter or basement structure

    International Nuclear Information System (INIS)

    Blatchford, J.M.A.

    1982-01-01

    A strong structure of precast concrete for use as a fallout shelter, tank, basement structure, blast-proof garage is described. It consists of several upright, concrete wall elements, including L-shaped sections, and at least one concrete roof element. The concrete elements are preferably encased in, and may also be supported on, a concrete surround which is formed in situ and which may be secured to the elements by projecting links. The structure may be assembled as an underground or above-ground building. This invention provides a strong structure of quite large span which is relatively simple in construction and can be rapidly assembled. (U.K.)

  4. The national scheme for monitoring radioactive fallout in milk

    International Nuclear Information System (INIS)

    Green, B.M.R.

    1979-01-01

    The National Radiological Protection Board, Harwell, assumed responsibility for the national milk monitoring scheme on Jan. 1, 1979. Milk contamination provides a good guide to radioactivity in the British diet. Brief reference is made to U.K. surveys of radioactive fallout in human food prior to January 1979, and current arrangements for the sampling of milk in the U.K. are explained. The milk is analysed for 90 Sr, 137 Cs and stable calcium. Additional samples are collected to check for 131 I or other short-lived isotopes in the event of atmospheric nuclear tests or accidents involving possible releases of radioactivity. (U.K.)

  5. Radioactive fallout from the Chernobyl nuclear reactor accident

    International Nuclear Information System (INIS)

    Beiriger, J.M.; Failor, R.A.; Marsh, K.V.; Shaw, G.E.

    1987-01-01

    Following the accident at the nuclear reactor at Chernobyl, in the Soviet Union on April 26, 1986, we performed a variety of measurements to determine the level of the radioactive fallout on the western United States. We used gamma-spectroscopy to analyze air filters from the areas around Lawrence Livermore National Laboratory (LLNL), California, and Barrow and Fairbanks, Alaska. Milk from California and imported vegetables were also analyzed. The levels of the various fission products detected were far below the maximum permissible concentration levels

  6. Urinary excretion of radionuclides from Marshallese exposed to fallout from the 1954 Bravo nuclear test.

    Science.gov (United States)

    Harris, Payne S; Simon, Steven L; Ibrahim, Shawki A

    2010-08-01

    Soon after the Bravo nuclear test at Bikini Atoll in the Marshall Islands on 1 March 1954, urine samples were collected for analysis of excreted radioactivity from native residents exposed to radioactive fallout on two atolls as well as from U.S. military personnel on a third atoll. The earliest acquired samples, obtained by the Los Alamos Scientific Laboratory (LASL), were assayed for various radionuclides and provided the first known measurements of (131)I in urine following exposure to fallout from a nuclear test. Over the course of 1954, many additional samples were collected by the LASL, as well as by the Atomic Energy Commission New York Operations Office's Health and Safety Laboratory and the Naval Radiological Defense Laboratory. Collectively, the groups sampled included Marshallese exposed on Rongelap and Ailinginae Atolls, American military weather observers temporarily resident on Rongerik Atoll, and sailors from the Japanese fishing vessel, the Lucky Dragon. While the bioassay measurement data and individual urine volumes have been crucial to various attempts to assess intakes of radioactivity and the related internal radiation doses among the Marshallese, those data have never been published in any peer-reviewed journal, but have been restricted to agency memoranda, laboratory reports, and summaries in some publications and book chapters. Reconstructions of internal doses to Marshallese in 1954 and in later years have depended on these data and, hence, they have considerable historical importance as well as importance to ongoing health risk projections for Marshallese. This paper presents much of the original data on urine volumes and radioactivity from the various assays of urine for radionuclides, and compares estimates of (131)I intakes made in 1954, 1985, 1987, and 2008.

  7. Radioactivity measurements in Europe after the Chernobyl accident. Part II: Fallout and deposition

    International Nuclear Information System (INIS)

    De Cort, M.; Graziani, G.; Raes, F.; Stanners, D.; Grippa, G.; Ricapito, I.

    1990-01-01

    The collection of deposition measurements, presented in this report and included in the floppy disk in the back cover has been put together as part of the REM programme (Radioactivity environmental Monitoring). This follows the compilation of air measurements (part 1) published previously (Raes, 1989). The objective of these compilations is to promote the integration of Chernobyl data on a European-wide basis to make them widely available in a coherent form for scientific study. Deposition measurements come in many forms (fallout, rain, soil) but all reflect the phenomena by which radionuclides in the air reach the surface. Depending on the manner of sampling, measurements can reflect integral values (e.g. from surface soil) or some fraction of the deposition (e.g. daily deposition using fallout or rain collectors). The latter can also be expressed as wet or dry according to the sampling apparatus used. The original sources of information from which this compilation was made vary widely : some of the data were obtained directly from floppy disks or tapes; others were copied manually from tables found in reports or papers in the scientific literature. The sets of measurements presented in this report were selected from this large patrimony of data in the REM data bank. Specific criteria were used to make this selection. Overall, only those data were used which had fully defined records. For daily deposition data actually sampled over 24 hourly periods were selected. With cumulative deposition care was taken to select data which covered the whole period of deposition marked by the passage of the cloud. The resulting data are presented on a unified format and as far as possible keep to individual measured values. In this manner the greatest flexibility is given to the user of this data

  8. The characterization and removal of Chernobyl debris in garden soils

    International Nuclear Information System (INIS)

    Andersson, K.G.

    1991-01-01

    Severe nuclear accidents such as the one in Chernobyl in 1986 may give unacceptably high external radiation levels, which even in the late phase may make a resettlement of an evacuated population impossible unless action is taken to decrease the exposure. As the urban land areas to be reclaimed may be very large the cost of the dose reducing countermeasure to be used may be an important factor. In the Chernobyl debris the most important radionuclides concerning the long term external radiation were found to be Cs-137, Cs-134, and Ru-106. Therefore, the aim of this work is to investigate the behaviour of these radionuclides in garden soils, and on this background to examine cost-effective methods by which a reduction of the dose from such areas to people living in urban or sub-urban environments can be achieved. The fixation of the radioactive cations in soil was investigated by means of soil profile sampling, soil texture analysis, and speciation experiments. It was found that most of the Chernobyl fallout caesium was extremely firmly fixed. Much of the ruthenium was more loosely bound, to organic material. The cost-effectiveness of some dose reducing countermeasures was examined on the background of small scale tests. Here it was found that about 95% of the activity could be removed with peelable fixatives based on PVA or lignin. (author) 1 tab., 7 ills., 25 refs

  9. Characterizing fallout material using Cs and Pu atom ratios in environmental samples from the FDNPP fallout zone

    Science.gov (United States)

    Richards, David; Dunne, James; Martin, Peter; Scott, Tom; Yamashiki, Yosuke; Coath, Chris; Chen, Hart

    2017-04-01

    Here we report the use of combined of Cs and Pu isotope measurements to investigate the extensive plumes of radioactive fallout from the disaster at Fukishima Daiichi nuclear power plant (FNDPP) in March 2011. Among the aims of our study are improved assessment of the physico-chemical nature and changing distribution of land-based fallout. 135Cs/137Cs and 134Cs/137Cs atom ratios are indicative of conditions that relate to the nuclear fission reactions responsible for producing the respective radiocaesium isotopes, and offer much more in terms of forensic and chronological analysis than monitoring 137Cs alone. We briefly present methods to quantify the atom ratios of Cs and Pu isotopes in soil, lichen and moss samples from FDNPP catchment using mass spectrometry (ThermoTRITON for Cs and ThermoNEPTUNE for Pu). High precision data from Fukushima are presented (e.g decay corrected 135Cs/137Cs atom ratio = 0.384 ± 0.001 (n = 5) for roadside dust from Iitate region), and these are in agreement with prelimary estimates by others. We also confirm results for IAEA-330, a spinach sample collected from Polesskoe, Ukraine and subject to contamination from the Chernobyl accident. In addition to Cs isotopes, we adopt Pu isotopes to add a further dimension to the forensic analysis. We discuss the corrections required for background levels prior to the disaster, possibility for multiple components of fallout and complicating factors associated with remobilisation during the clean-up operation. In parallel with this work on digests and leaches from bulk environmental samples, we are refining methods for particle identification, isolation and characterisation using a complementary sequence of cutting-edge materials and manipulation techniques, including combined electron microscopy, focused ion beam techniques (Dualbeam), nano/micro manipulators and nano-scale imaging x-ray photoelectron spectroscopy (NanoESCA) and microCT.

  10. Colisional Cloud Debris and Propelled Evasive Maneuvers

    Science.gov (United States)

    Ferreira, L. S.; Jesus, A. D. C.; Carvalho, T. C. F.; Sousa, R. R.

    2017-10-01

    Space debris clouds exist at various altitudes in the environment outside the Earth. Fragmentation of debris and/or collision between the debris of a cloud increases the amount of debris, producing smaller debris. This event also increases significantly the chances of collision with operational vehicles in orbit. In this work we study clouds of debris that are close to a spacecraft in relation to its distance from the center of the Earth. The results show several layers of colliding debris depending on their size over time of evasive maneuvers of the vehicle. In addition, we have tested such maneuvers for propulsion systems with a linear and exponential mass variation model. The results show that the linear propulsion system is more efficient.

  11. The fast debris evolution model

    Science.gov (United States)

    Lewis, H. G.; Swinerd, G. G.; Newland, R. J.; Saunders, A.

    2009-09-01

    The 'particles-in-a-box' (PIB) model introduced by Talent [Talent, D.L. Analytic model for orbital debris environmental management. J. Spacecraft Rocket, 29 (4), 508-513, 1992.] removed the need for computer-intensive Monte Carlo simulation to predict the gross characteristics of an evolving debris environment. The PIB model was described using a differential equation that allows the stability of the low Earth orbit (LEO) environment to be tested by a straightforward analysis of the equation's coefficients. As part of an ongoing research effort to investigate more efficient approaches to evolutionary modelling and to develop a suite of educational tools, a new PIB model has been developed. The model, entitled Fast Debris Evolution (FADE), employs a first-order differential equation to describe the rate at which new objects ⩾10 cm are added and removed from the environment. Whilst Talent [Talent, D.L. Analytic model for orbital debris environmental management. J. Spacecraft Rocket, 29 (4), 508-513, 1992.] based the collision theory for the PIB approach on collisions between gas particles and adopted specific values for the parameters of the model from a number of references, the form and coefficients of the FADE model equations can be inferred from the outputs of future projections produced by high-fidelity models, such as the DAMAGE model. The FADE model has been implemented as a client-side, web-based service using JavaScript embedded within a HTML document. Due to the simple nature of the algorithm, FADE can deliver the results of future projections immediately in a graphical format, with complete user-control over key simulation parameters. Historical and future projections for the ⩾10 cm LEO debris environment under a variety of different scenarios are possible, including business as usual, no future launches, post-mission disposal and remediation. A selection of results is presented with comparisons with predictions made using the DAMAGE environment model

  12. Space Tourism: Orbital Debris Considerations

    Science.gov (United States)

    Mahmoudian, N.; Shajiee, S.; Moghani, T.; Bahrami, M.

    2002-01-01

    Space activities after a phase of research and development, political competition and national prestige have entered an era of real commercialization. Remote sensing, earth observation, and communication are among the areas in which this growing industry is facing competition and declining government money. A project like International Space Station, which draws from public money, has not only opened a window of real multinational cooperation, but also changed space travel from a mere fantasy into a real world activity. Besides research activities for sending man to moon and Mars and other outer planets, space travel has attracted a considerable attention in recent years in the form of space tourism. Four countries from space fairing nations are actively involved in the development of space tourism. Even, nations which are either in early stages of space technology development or just beginning their space activities, have high ambitions in this area. This is worth noting considering their limited resources. At present, trips to space are available, but limited and expensive. To move beyond this point to generally available trips to orbit and week long stays in LEO, in orbital hotels, some of the required basic transportations, living requirements, and technological developments required for long stay in orbit are already underway. For tourism to develop to a real everyday business, not only the price has to come down to meaningful levels, but also safety considerations should be fully developed to attract travelers' trust. A serious hazard to space activities in general and space tourism in particular is space debris in earth orbit. Orbiting debris are man-made objects left over by space operations, hazardous to space missions. Since the higher density of debris population occurs in low earth orbit, which is also the same orbit of interest to space tourism, a careful attention should be paid to the effect of debris on tourism activities. In this study, after a

  13. Fallout 137Cs in reindeer herders in Arctic Norway.

    Science.gov (United States)

    Skuterud, Lavrans; Thørring, Håvard

    2015-03-03

    Reindeer herders in the Arctic were among the most heavily exposed populations to the global fallout from nuclear weapons testing in the 1950s and 1960s, due to high transfer of radionuclides in the lichens-reindeer-human food chain. Annual studies of (137)Cs in reindeer herders in Kautokeino, Norway, were initiated in 1965 to monitor radiation doses and follow environmental (137)Cs behavior. The (137)Cs concentrations declined from the peak in 1965 with effective half-times of 6-8 years, only interrupted by a temporary doubling in levels from 1986 to 1987 due to the Chernobyl fallout. During the period of 1950-2010 an average herder received an integrated effective dose from incorporated (137)Cs of about 18 mSv. This dose represents an insignificant increase in the risk for developing cancer. Health studies even show a significantly lower cancer incidence among Sámis and reindeer herders in northern Norway compared to other populations in the same area.

  14. Numerical module for debris behavior under severe accident conditions

    International Nuclear Information System (INIS)

    Kisselev, A.E.; Kobelev, G.V.; Strizhov, V.F.; Vasiliev, A.D.

    2005-01-01

    The late phase of a hypothetical severe accident in a nuclear reactor is characterized by the appearance of porous debris and liquid pools in core region and lower head of the reactor vessel. Thermal hydraulics and heat transfer in these regions are very important for adequate analysis of severe accident dynamics. The purpose of this work is to develop a universal module which is able to model above-mentioned phenomena on the basis of modern physical concepts. The original approach for debris evolution is developed from classical principles using a set of parameters including debris porosity; average particle diameter; temperatures and mass fractions of solid, liquid and gas phases; specific interface areas between different phases; effective thermal conductivity of each phase, including radiative heat conductivity; mass and energy fluxes through the interfaces. The calculation results of several tests on modeling of porous debris behavior, including the MP-1 experiment, are presented in comparison with experimental data. The results are obtained using this module implemented into the Russian best estimate code, RATEG/SVECHA/HEFEST, which was developed for modeling severe accident thermal hydraulics and late phase phenomena in VVER nuclear power plants. (author)

  15. Space Debris Alert System for Aviation

    Science.gov (United States)

    Sgobba, Tommaso

    2013-09-01

    Despite increasing efforts to accurately predict space debris re-entry, the exact time and location of re-entry is still very uncertain. Partially, this is due to a skipping effect uncontrolled spacecraft may experience as they enter the atmosphere at a shallow angle. Such effect difficult to model depends on atmospheric variations of density. When the bouncing off ends and atmospheric re-entry starts, the trajectory and the overall location of surviving fragments can be precisely predicted but the time to impact with ground, or to reach the airspace, becomes very short.Different is the case of a functional space system performing controlled re-entry. Suitable forecasts methods are available to clear air and maritime traffic from hazard areas (so-called traffic segregation).In US, following the Space Shuttle Columbia accident in 2003, a re-entry hazard areas location forecast system was putted in place for the specific case of major malfunction of a Reusable Launch Vehicles (RLV) at re-entry. The Shuttle Hazard Area to Aircraft Calculator (SHAAC) is a system based on ground equipment and software analyses and prediction tools, which require trained personnel and close coordination between the organization responsible for RLV operation (NASA for Shuttle) and the Federal Aviation Administration. The system very much relies on the operator's capability to determine that a major malfunction has occurred.This paper presents a US pending patent by the European Space Agency, which consists of a "smart fragment" using a GPS localizer together with pre- computed debris footprint area and direct broadcasting of such hazard areas.The risk for aviation from falling debris is very remote but catastrophic. Suspending flight over vast swath of airspace for every re-entering spacecraft or rocket upper stage, which is a weekly occurrence, would be extremely costly and disruptive.The Re-entry Direct Broadcasting Alert System (R- DBAS) is an original merging and evolution of the Re

  16. Warm Debris Disks from WISE

    Science.gov (United States)

    Padgett, Deborah L.

    2011-01-01

    "The Wide Field Infrared Survey Explorer (WISE) has just completed a sensitive all-sky survey in photometric bands at 3.4, 4.6, 12, and 22 microns. We report on a preliminary investigation of main sequence Hipparcos and Tycho catalog stars with 22 micron emission in excess of photospheric levels. This warm excess emission traces material in the circumstellar region likely to host terrestrial planets and is preferentially found in young systems with ages warm debris disk candidates are detected among FGK stars and a similar number of A stars within 120 pc. We are in the process of obtaining spectra to determine spectral types and activity level of these stars and are using HST, Herschel and Keck to characterize the dust, multiplicity, and substellar companions of these systems. In this contribution, we will discuss source selection methods and individual examples from among the WISE debris disk candidates. "

  17. Changes in the levels of radioactive fall-out and the resulting radiation doses to man in the United Kingdom

    International Nuclear Information System (INIS)

    Loutit, J.F.; Marley, W.G.; Mayneord, W.V.; Russell, R.S.

    1960-01-01

    In the period covered by the Council's 1956 report, that is, up to the spring of 1956, the radioactive debris falling in the United Kingdom had arisen from a large number of small nuclear explosions, chiefly in Nevada, and from a few large nuclear explosions mainly in the Pacific, especially in March, 1954. It was recognized that the doses of radiation to persons from the deposition of debris arising from the smaller nuclear explosions would be far outweighed by those from the larger explosions. The material reaching the U.K. from the latter at that time was found to have an apparent age (determined from the ratio of strontium 89 to strontium 90 which ranged from 7 to 14 months. In these circumstances the dose contributed by the isotopes of relatively short life (say, two months or less) was much less important than the dose from the long-lived isotopes such as caesium 137 and strontium 90. From the autumn of 1956 the pattern of testing changed. A high proportion of the explosions carried out were of megaton size and took place in higher latitudes in the northern hemisphere. As a result the short-lived isotopes became relatively more important and, with the heavy testing of nuclear devices in the Arctic in October, 1958, the contribution of radioactive fall-out to the background dose-rate in air in the open rose in the spring of 1959 so that, for a period of a month or two, it amounted to some 30 per cent of the natural background. This rise in dose-rate can be attributed to two main causes, namely, the increase in the rate of testing and the shorter time during which the fission products from the tests in the autumn in northern latitudes, particularly in the Arctic, have remained airborne

  18. Changes in the levels of radioactive fall-out and the resulting radiation doses to man in the United Kingdom

    Energy Technology Data Exchange (ETDEWEB)

    Loutit, J F; Marley, W G; Mayneord, W V; Russell, R S

    1960-12-01

    In the period covered by the Council's 1956 report, that is, up to the spring of 1956, the radioactive debris falling in the United Kingdom had arisen from a large number of small nuclear explosions, chiefly in Nevada, and from a few large nuclear explosions mainly in the Pacific, especially in March, 1954. It was recognized that the doses of radiation to persons from the deposition of debris arising from the smaller nuclear explosions would be far outweighed by those from the larger explosions. The material reaching the U.K. from the latter at that time was found to have an apparent age (determined from the ratio of strontium 89 to strontium 90 which ranged from 7 to 14 months. In these circumstances the dose contributed by the isotopes of relatively short life (say, two months or less) was much less important than the dose from the long-lived isotopes such as caesium 137 and strontium 90. From the autumn of 1956 the pattern of testing changed. A high proportion of the explosions carried out were of megaton size and took place in higher latitudes in the northern hemisphere. As a result the short-lived isotopes became relatively more important and, with the heavy testing of nuclear devices in the Arctic in October, 1958, the contribution of radioactive fall-out to the background dose-rate in air in the open rose in the spring of 1959 so that, for a period of a month or two, it amounted to some 30 per cent of the natural background. This rise in dose-rate can be attributed to two main causes, namely, the increase in the rate of testing and the shorter time during which the fission products from the tests in the autumn in northern latitudes, particularly in the Arctic, have remained airborne.

  19. Estimating Fallout Building Attributes from Architectural Features and Global Earthquake Model (GEM) Building Descriptions

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, Michael B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kane, Staci R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-03-01

    A nuclear explosion has the potential to injure or kill tens to hundreds of thousands (or more) of people through exposure to fallout (external gamma) radiation. Existing buildings can protect their occupants (reducing fallout radiation exposures) by placing material and distance between fallout particles and individuals indoors. Prior efforts have determined an initial set of building attributes suitable to reasonably assess a given building’s protection against fallout radiation. The current work provides methods to determine the quantitative values for these attributes from (a) common architectural features and data and (b) buildings described using the Global Earthquake Model (GEM) taxonomy. These methods will be used to improve estimates of fallout protection for operational US Department of Defense (DoD) and US Department of Energy (DOE) consequence assessment models.

  20. Behavior of explosion debris clouds

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    In the normal course of events the behavior of debris clouds created by explosions will be of little concern to the atomic energy industry. However, two situations, one of them actual and one postulated, exist where the rise and spread of explosion clouds can affect site operations. The actual occurrence would be the detonation of nuclear weapons and the resultant release and transport of radioactive debris across the various atomic energy installations. Although the activity of the diffusing cloud is not of biological concern, it may still be sufficiently above background to play havoc with the normal readings of sensitive monitoring instruments. If it were not known that these anomalous readings resulted from explosion debris, considerable time and expense might be required for on-site testing and tracing. Fortunately it is usually possible, with the use of meteorological data and forecasts, to predict when individual sites are affected by nuclear weapon debris effects. The formation rise, and diffusion of weapon clouds will be discussed. The explosion of an atomic reactor is the postulated situation. It is common practice in reactor hazard analysis to assume a combination of circumstances which might result in a nuclear incident with a release of material to the atmosphere. It is not within the scope of this report to examine the manifold plausibilities that might lead to an explosion or the possible methods of release of gaseous and/or particulates from such an occurrence. However, if the information of a cloud is assumed and some idea of its energy content is obtainable, estimates of the cloud behavior in the atmosphere can be made

  1. Space Debris and Observational Astronomy

    Science.gov (United States)

    Seitzer, Patrick

    2018-01-01

    Since the launch of Sputnik 1 in 1957, astronomers have faced an increasing number of artificial objects contaminating their images of the night sky. Currently almost 17000 objects larger than 10 cm are tracked and have current orbits in the public catalog. Active missions are only a small fraction of these objects. Most are inactive satellites, rocket bodies, and fragments of larger objects: all space debris. Several mega-constellations are planned which will increase this number by 20% or more in low Earth orbit (LEO). In terms of observational astronomy, this population of Earth orbiting objects has three implications: 1) the number of streaks and glints from spacecraft will only increase. There are some practical steps that can be taken to minimize the number of such streaks and glints in astronomical imaging data. 2) The risk to damage to orbiting astronomical telescopes will only increase, particularly those in LEO. 3) If you are working on a plan for an orbiting telescope project, then there are specific steps that must be taken to minimize space debris generation during the mission lifetime, and actions to safely dispose of the spacecraft at end of mission to prevent it from becoming space debris and a risk to other missions. These steps may involve sacrifices to mission performance and lifetime, but are essential in today's orbital environment.

  2. ORDEM 3.0 and MASTER-2009 Modeled Small Debris Population Comparison

    Science.gov (United States)

    Krisko, P. H.; Flegel, S.

    2014-01-01

    The latest versions of the two premier orbital debris engineering models, NASA's ORDEM 3.0 and ESA's MASTER-2009, have been publically released. Both models have gone through significant advancements since inception, and now represent the state-of-the-art in orbital debris knowledge of their respective agencies. The purpose of these models is to provide satellite designers/operators and debris researchers with reliable estimates of the artificial debris environment in low Earth orbit (LEO) to geosynchronous orbit (GEO). The small debris environment within the size range of 1 mm to 1 cm is of particular interest to both human and robotic spacecraft programs, particularly in LEO. These objects are much more numerous than larger trackable debris and can have enough momentum to cause significant, if not catastrophic, damage to spacecraft upon impact. They are also small enough to elude routine detection by existing observation systems (radar and telescope). Without reliable detection the modeling of these populations has always coupled theoretical origins with supporting observational data in different degrees. In this paper, we present and detail the 1 mm to 1 cm orbital debris populations from both ORDEM 3.0 and MASTER-2009 in LEO. We review population categories: particle sources for MASTER-2009, particle densities for ORDEM 3.0. We describe data sources and their uses, and supporting models. Fluxes on spacecraft for chosen orbits are also presented and discussed within the context of each model.

  3. Review of medical findings in a Marshallese population twenty-six years after accidental exposure to radioactive fallout

    International Nuclear Information System (INIS)

    Conard, R.A.; Paglia, D.E.; Larsen, P.R.

    1980-01-01

    In March 1954, radioactive debris from a thermonuclear weapon test at Bikini Atoll deviated from predicted trajectories and contaminated several atolls in the northern Marshall Islands. As a result, 239 native inhabitants of these islands along with 28 American servicemen and 23 Japanese fishermen received variably severe exposures to diverse ionizing radiations. Fallout material consisted largely of mixed fission products with small amounts of neutron-induced radionuclides and minimal amounts of fissionable elements, producing a complex spectrum of electromagnetic and particulate radiation. Individuals were exposed to deeply penetrating, whole-body gamma irradiation, to internal radiation emitters assimilated either by inhalation or by ingestion of contaminated water and food, and to direct radiation from material accumulating on body surfaces. That accident initiated a cascade of events, medical, social and political, which continue in varying forms to this day. Most of these have been discussed in the open medical literature and in periodic reports issued by the medical team headquartered at Brookhaven National Laboratory. This report attempts to summarize some of the principal findings of medical significnce that have been observed during the subsequent 26 years with particular emphasis on the last six years

  4. Status of annual plant species in the Baneberry fallout pattern first and sixth years after initial irradiation

    International Nuclear Information System (INIS)

    Rhoads, W.A.

    1977-01-01

    At Project Baneberry on December 18, 1970, there was an accidental venting of radioactive debris into the environment which resulted in the irradiation of vegetation about 1.5 km to the north with doses estimated to reach a maximum of 6.2 K rads, beta plus gamma. At the highest doses, 35 percent of the dominant shrub in the area, Coleogyne (black brush), were killed and 65% severely damaged; and at lesser doses there was correspondingly less damage. Other species of shrubs were also affected. Grayia spinosa showed a low frequency of stem fasciation at the higher doses as well as other manifestations of radiation damage. In June 1971, the annual plant species which were probably small seedlings at fallout time were more frequently absent from the higher radiation areas than in the lower. At the same time, there was a greater frequency of higher dry weights produced by annuals at the higher radiation exposures. The frequency of occurrence of annuals varied from means of 8.5/m 2 at the higher doses to 24.3/m 2 at the lower doses. In June 1976, five years after irradiation, there were 300 to 400 plants/m 2 . By extrapolating the plants/m 2 against dose back to zero plants/m 2 , some indication of radiation doses which might destroy all annuals was derived

  5. Review of medical findings in a Marshallese population twenty-six years after accidental exposure to radioactive fallout

    Energy Technology Data Exchange (ETDEWEB)

    Conard, R.A.; Paglia, D.E.; Larsen, P.R.

    1980-01-01

    In March 1954, radioactive debris from a thermonuclear weapon test at Bikini Atoll deviated from predicted trajectories and contaminated several atolls in the northern Marshall Islands. As a result, 239 native inhabitants of these islands along with 28 American servicemen and 23 Japanese fishermen received variably severe exposures to diverse ionizing radiations. Fallout material consisted largely of mixed fission products with small amounts of neutron-induced radionuclides and minimal amounts of fissionable elements, producing a complex spectrum of electromagnetic and particulate radiation. Individuals were exposed to deeply penetrating, whole-body gamma irradiation, to internal radiation emitters assimilated either by inhalation or by ingestion of contaminated water and food, and to direct radiation from material accumulating on body surfaces. That accident initiated a cascade of events, medical, social and political, which continue in varying forms to this day. Most of these have been discussed in the open medical literature and in periodic reports issued by the medical team headquartered at Brookhaven National Laboratory. This report attempts to summarize some of the principal findings of medical significnce that have been observed during the subsequent 26 years with particular emphasis on the last six years.

  6. External doses from radioactive fallout. Dosimetry and levels

    International Nuclear Information System (INIS)

    Woehni, T.

    1995-01-01

    The design, manufacture and calibration of a TL-based dosemeter for measurement of low level external photon radiation are presented. The dosemeter is based on CaF 2 with 2 mm brass filter for energy compensation. It is able to resolve a 8% dose increase relative to natural background radiation. With this dosemeter external dose measurements were made in 6 villages in a heavily contaminated region in Russia (Chernobyl fallout), in order to assess external doses to the population. The results were analyzed in the light of additional existing information on radioactive deposition, social habits, decontamination measures and other influencing technical and physical factors. The observed dose values were lower than theoretical estimates of external doses based on published values for external dose levels relative to the level of contamination. 84 refs., 7 figs., 5 tabs

  7. Estimating soil erosion losses in Korea with fallout cesium-137

    International Nuclear Information System (INIS)

    Menzel, R.G.; Pilkyun Jung; Kwanshig Ryu; Kitai Um

    1987-01-01

    The contents of fallout 137 Cs in soil profiles were used to estimate erosion losses from steeply sloping croplands in Korea. Seven undisturbed sites with no apparent erosion or deposition, and 15 cropland sites were examined to a depth of 30 cm. The cropland sites had been cultivated for periods ranging from 5 to more than 80 y (median 10 y), and their slopes ranged from 5 to 26% (median 13%). All except one of the cropland sites contained less 137 Cs than undisturbed sites in the same area. Three cropland sites contained essentially no 137 Cs, indicating erosion of the entire cultivated layer of soil in from 6 to 10 years. Other cropland sites, particularly those with sandy texture, showed little loss of 137 Cs over longer periods of cultivation. Cesium-137 measurements may be useful in identifying site characteristics that reduce the vulnerability of sloping soils to erosion damage. (author)

  8. Chernobyl team seeks aid for fallout cleanup studies

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    British nuclear experts have begun raising international aid agency interest in financing studies into cleaning up vast areas of the Ukraine still contaminated with fallout from the Chernobyl reactor explosion in April 1986. In a new 11-month investigation of the area outside an 18.6-mile radius of Chernobyl, the experts identified 80 necessary studies estimated to cost $62 million. open-quotes That's just to get the system up and running. The total cost is much larger, but the authors don't yet know how much,close quotes says investigation coordinator Alan Eggleton of AEA Technology Ltd., Harwell, which led the study team. According to the report, radioactivity contaminated 19,000 sq miles of the Ukraine. The government is now spending some 12% of its income on mitigating the contamination, although most spending is for victim compensation and resettlement

  9. External doses from radioactive fallout. Dosimetry and levels

    Energy Technology Data Exchange (ETDEWEB)

    Woehni, T

    1996-12-31

    The design, manufacture and calibration of a TL-based dosemeter for measurement of low level external photon radiation are presented. The dosemeter is based on CaF{sub 2} with 2 mm brass filter for energy compensation. It is able to resolve a 8% dose increase relative to natural background radiation. With this dosemeter external dose measurements were made in 6 villages in a heavily contaminated region in Russia (Chernobyl fallout), in order to assess external doses to the population. The results were analyzed in the light of additional existing information on radioactive deposition, social habits, decontamination measures and other influencing technical and physical factors. The observed dose values were lower than theoretical estimates of external doses based on published values for external dose levels relative to the level of contamination. 84 refs., 7 figs., 5 tabs.

  10. External doses from radioactive fallout. Dosimetry and levels

    Energy Technology Data Exchange (ETDEWEB)

    Woehni, T.

    1995-12-31

    The design, manufacture and calibration of a TL-based dosemeter for measurement of low level external photon radiation are presented. The dosemeter is based on CaF{sub 2} with 2 mm brass filter for energy compensation. It is able to resolve a 8% dose increase relative to natural background radiation. With this dosemeter external dose measurements were made in 6 villages in a heavily contaminated region in Russia (Chernobyl fallout), in order to assess external doses to the population. The results were analyzed in the light of additional existing information on radioactive deposition, social habits, decontamination measures and other influencing technical and physical factors. The observed dose values were lower than theoretical estimates of external doses based on published values for external dose levels relative to the level of contamination. 84 refs., 7 figs., 5 tabs.

  11. Cancer of the thyroid and 131I fallout in Norway

    International Nuclear Information System (INIS)

    Oftedal, P.; Lund, E.

    1983-01-01

    From 1953 to 1962 Norway received relatively high levels of radioactive fallout. On the basis of extensive measurements in air, precipitation, food and humans, the dose to the thyroid due to 131 I has been calculated. Cancer registration in Norway is practically completely efficient because of obligatory notification of the Cancer Registry by physicians, pathology laboratories, and the Central Bureau of Statistics of all cases or death certificates concerning cancer. Analysis of the Cancer Registry data from 1953 to 1980 concerning birth cohorts 1936 to 1961 indicates an overall increasing trend in thyroid cancer morbidity, most pronounced in female cohorts born 1930-50. The highest, most abrupt irregularities reveal a coincidence of high numbers with high 131 I content in milk consumed during the years of prepuberty and puberty. Possible interpretations are discussed. (author)

  12. Accumulation of plutonium from fallout in southern Finns and Lapps

    International Nuclear Information System (INIS)

    Mussalo-Rauhamaa, H.

    1981-01-01

    The body burden of 239 , 240 Pu and 238 Pu from fallout in southern Finns and Lapps was determined by ion exchange and alpha-spectrometry through analyses of autopsy tissue samples. Comparing the body burden against the inhalation and ingestion intake of plutonium of these population groups the fractional absorption factor for plutonium from the human gastrointestinal tract and lungs was estinated. In addition, the determined tissue values were compared with those computed with the aid of the ICRP lung model and plutonium content of surface air in the Helsinki area. The 239 , 240 Pu concentrations per wet weight of tissue descended in the order liver>lymph nodes>bone>lung>testes>muscle. A dependence of plutonium content of tissues on the amount of air inhaled by the person during the fallout period and, thus, on the age of the person, was shown. The skeletal distribution of plutonium in man was roughly similar to that reported for animals. The ratio of 239 , 240 Pu content in vertebrae to that in ribs was 1.4, on the average, and the rib/femur ratio 1.0. The average body burden of 239 , 240 Pu in adult southern Finn and Lapp males was estimated to be 1.2 pCi (44.4 mBq), of which about 51 per cent was located in liver and 40 per cent in skeleton. The estimates for the ingestion and inhalation intake of 239 , 240 Pu during the period 1945-78 were 36 and 18 pCi (1.3, 0.67 Bq) and 540 and 13 pCi (19.9, 0.48 Bq) for southern Finn and Lapp males, respectively. The estimated fractional absorption factor of plutonium in humn GI-tract was of the order (6-9)x10 -4 and in lungs (7.5-8.5)x10 -2 . (author)

  13. Pathways and Distribution of Marine Debris Around a Remote Caribbean Island, Little Cayman

    Science.gov (United States)

    Camp, L.; Marsh, L.; O'Keefe, A.; Duran, J.; Wilcox, S. M.; James, R.; Cowan, E.

    2011-12-01

    Marine Debris is a major environmental concern that affects all levels of marine life. On remote beaches in the Caribbean, where human populations are minimal, marine debris is largely deposited by ocean currents. The ocean is estimated to be littered with over 6 million metric tons of trash per year with 90% coming from land sources, but little is known about the exact sources and pathways for the debris. In 2006, on Little Cayman Island, coastal debris was collected at two coastal areas where removal of debris had not occurred in at least 9 years and along 2000 meters squared. One site was located on the north side, while the other site was located on the south side of the island. Both sites were located in reef-protected coastal zones. These two sites were revisited in 2007, 2010, and 2011 to determine the volume, weight, and type of debris arriving annually and to assess the importance of different coastal processes in deposition. In 2011, eight turtle nesting beaches were added to the study and a total of 11,186 liters of debris was collected from 1600 meters of coastline. The island lies in a northeast southwest orientation. The south-side of the island is influenced largely by prevailing trade winds, currents and tropical storms, traveling across the Caribbean from the east. Currents, eddies, and Norwesters would presumably deposit debris on the north side of the island. Approximately five times the amount of debris is deposited on the south side of the island than on the north side of the island. From the total debris collected, 72.45% was plastic, 8.23% shoes, 6.37% ropes & nets , 5.13% glass, 4.37% styrofoam, and 3.44% contained other debris. The marine debris originated in 8 different countries, and it is estimated that there is collectively 223,721 liters (11,635 kg) covering the shores of the entire island. Remarkably, debris found on Little Cayman in 2011 was traced to the 2010 Haitian earthquake relief effort.

  14. Porous chromatographic materials as substrates for preparing synthetic nuclear explosion debris particles

    International Nuclear Information System (INIS)

    Harvey, S.D.; Carman, A.J.; Martin Liezers; Antolick, K.C.; Garcia, B.J.; Eiden, G.C.; Sweet, L.E.

    2013-01-01

    Several porous chromatographic materials were investigated as synthetic substrates for preparing surrogate nuclear explosion debris particles. Eighteen metals, including some of forensic interest, were loaded onto materials by immersing them in metal solutions (556 mg/L of each metal) to fill the pores, applying gentle heat (110 deg C) to drive off water, and then treating them at high temperatures (up to 800 deg C) in air to form less soluble metal species. High-boiling-point metals were uniformly loaded on spherical controlled-pore glass to emulate early fallout, whereas low-boiling-point metals were loaded on core-shell silica to represent coated particles formed later in the nuclear fallout-formation process. Analytical studies characterized material balance and the formation of recalcitrant species. Metal loading was 1.5-3 times higher than expected from the pore volume alone, a result attributed to surface coating. Most metals were passively loaded; that is, solutions filled the pores without active metal discrimination. However, niobium and tin concentrations were lower in solutions after pore filling, and were found in elevated concentrations in the final products, indicating selective loading. High-temperature treatments caused reduced solubility of several metals, and the loss of some volatile species (rhenium and tellurium). Sample preparation reproducibility was high (the inter- and intra-batch relative standard deviations were 7.8 and 0.84 %, respectively) indicating suitability for use as a working standard for analytical methods development. We anticipate future standardized radionuclide-loaded materials will find use in radioanalytical methods development and/or serve as a starting material for the synthesis of more complex nuclear explosion debris forms (e.g., Trinitite). (author)

  15. Small satellites and space debris issues

    Science.gov (United States)

    Yakovlev, M.; Kulik, S.; Agapov, V.

    2001-10-01

    The objective of this report is the analysis of the tendencies in designing of small satellites (SS) and the effect of small satellites on space debris population. It is shown that SS to include nano- and pico-satellites should be considered as a particularly dangerous source of space debris when elaborating international standards and legal documents concerning the space debris problem, in particular "International Space Debris Mitigation Standard". These issues are in accordance with the IADC goals in its main activity areas and should be carefully considered within the IADC framework.

  16. Process Knowledge Summary Report for Materials and Fuels Complex Contact-Handled Transuranic Debris Waste

    Energy Technology Data Exchange (ETDEWEB)

    R. P. Grant; P. J. Crane; S. Butler; M. A. Henry

    2010-02-01

    This Process Knowledge Summary Report summarizes the information collected to satisfy the transportation and waste acceptance requirements for the transfer of transuranic (TRU) waste between the Materials and Fuels Complex (MFC) and the Advanced Mixed Waste Treatment Project (AMWTP). The information collected includes documentation that addresses the requirements for AMWTP and the applicable portion of their Resource Conservation and Recovery Act permits for receipt and treatment of TRU debris waste in AMWTP. This report has been prepared for contact-handled TRU debris waste generated by the Idaho National Laboratory at MFC. The TRU debris waste will be shipped to AMWTP for purposes of supercompaction. This Process Knowledge Summary Report includes information regarding, but not limited to, the generation process, the physical form, radiological characteristics, and chemical contaminants of the TRU debris waste, prohibited items, and packaging configuration. This report, along with the referenced supporting documents, will create a defensible and auditable record for waste originating from MFC.

  17. Reduced clot debris size using standing waves formed via high intensity focused ultrasound

    Science.gov (United States)

    Guo, Shifang; Du, Xuan; Wang, Xin; Lu, Shukuan; Shi, Aiwei; Xu, Shanshan; Bouakaz, Ayache; Wan, Mingxi

    2017-09-01

    The feasibility of utilizing high intensity focused ultrasound (HIFU) to induce thrombolysis has been demonstrated previously. However, clinical concerns still remain related to the clot debris produced via fragmentation of the original clot potentially being too large and hence occluding downstream vessels, causing hazardous emboli. This study investigates the use of standing wave fields formed via HIFU to disintegrate the thrombus while achieving a reduced clot debris size in vitro. The results showed that the average diameter of the clot debris calculated by volume percentage was smaller in the standing wave mode than in the travelling wave mode at identical ultrasound thrombolysis settings. Furthermore, the inertial cavitation dose was shown to be lower in the standing wave mode, while the estimated cavitation bubble size distribution was similar in both modes. These results show that a reduction of the clot debris size with standing waves may be attributed to the particle trapping of the acoustic potential well which contributed to particle fragmentation.

  18. Porous debris behavior modeling of QUENCH-02, QUENCH-03 and QUENCH-09 experiments

    International Nuclear Information System (INIS)

    Kisselev, A.E.; Kobelev, G.V.; Strizhov, V.F.; Vasiliev, A.D.

    2006-01-01

    The heat-up, melting, relocation, hydrogen generation phenomena, relevant for high-temperature stages both in a reactor case and small-scale integral tests like QUENCH, are governed in particular by heat and mass transfer in porous debris and molten pools which are formed in the core region. Porous debris formation and behavior in QUENCH experiments (QUENCH-02, QUENCH-03, QUENCH-09) plays a considerable role and its adequate modeling is important for thermal analysis. In particular, the analysis of QUENCH experiments shows that the major hydrogen release takes place in debris and melt regions formed in the upper part of the fuel assembly. The porous debris model was implemented in the Russian best estimate numerical code RATEG/SVECHA/HEFEST developed for modelling thermal hydraulics and severe accident phenomena in a reactor. The original approach for debris evolution is developed in the model from classical principles using a set of parameters including debris porosity; average particle diameter; temperatures and mass fractions of solid, liquid and gas phases; specific interface areas between different phases; effective thermal conductivity of each phase, including radiative heat conductivity; mass and energy fluxes through the interfaces. The debris model is based on the system of continuity, momentum and energy conservation equations, which consider the dynamics of volume-averaged velocities and temperatures of fluid, solid and gaseous phases of porous debris. The model is used for calculation of QUENCH experiments. The results obtained by the model are compared to experimental data concerning different aspects of thermal behavior: thermal hydraulics of porous debris, radiative heat transfer in a porous medium, the generalized melting and refreezing behavior of materials, hydrogen production. (author)

  19. Numerical investigation of debris materials prior to debris flow hazards using satellite images

    Science.gov (United States)

    Zhang, N.; Matsushima, T.

    2018-05-01

    The volume of debris flows occurred in mountainous areas is mainly affected by the volume of debris materials deposited at the valley bottom. Quantitative evaluation of debris materials prior to debris flow hazards is important to predict and prevent hazards. At midnight on 7th August 2010, two catastrophic debris flows were triggered by the torrential rain from two valleys in the northern part of Zhouqu City, NW China, resulting in 1765 fatalities and huge economic losses. In the present study, a depth-integrated particle method is adopted to simulate the debris materials, based on 2.5 m resolution satellite images. In the simulation scheme, the materials are modeled as dry granular solids, and they travel down from the slopes and are deposited at the valley bottom. The spatial distributions of the debris materials are investigated in terms of location, volume and thickness. Simulation results show good agreement with post-disaster satellite images and field observation data. Additionally, the effect of the spatial distributions of the debris materials on subsequent debris flows is also evaluated. It is found that the spatial distributions of the debris materials strongly influence affected area, runout distance and flow discharge. This study might be useful in hazard assessments prior to debris flow hazards by investigating diverse scenarios in which the debris materials are unknown.

  20. Consequences in Norway of a hypothetical accident at Sellafield: Potential release - transport and fallout

    International Nuclear Information System (INIS)

    Ytre-Eide, M. A.; Standring, W.J.F.; Amundsen, I.; Sickel, M.; Liland, A.; Saltbones, J.; Bartnicki, J.; Haakenstad, H.; Salbu, B.

    2009-03-01

    This report focuses on transport and fallout from 'worst-case' scenarios based on a hypothetical accident at the B215 facility for storing Highly Active Liquors (HAL) at Sellafield. The scenarios involve an atmospheric release of between 0.1-10 % of the total HAL inventory; only transport and fallout of 137 Cs is considered in this case study. Simulations resulted in between 0.1-50 times the maximum 137 Cs fallout experienced in the most contaminated areas in Norway after the Chernobyl accident. (Author)

  1. Chapter 4: Measurements of total beta-activity in the fallout

    International Nuclear Information System (INIS)

    Duggleby, J.C.; Johannessen, J.C.; Kotler, L.H.; Stewart, F.M.

    1974-01-01

    In order to provide information on fresh fission products in fallout reaching Australia from nuclear tests being conducted by France in Polynesia, measurements were made of total beta activity in daily fallout deposition of 25 Australian sampling stations covering a three month period from 25 July to 23 October 1973. The methods employed to measure the radioactivity of the samples are described and the data on total beta-activity, and the calculated external gamma radiation doses from fresh fallout are presented. (R.L.)

  2. Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation

    Energy Technology Data Exchange (ETDEWEB)

    McMurtry, G.M.; Schneider, R.C. (Hawaii Univ., Honolulu (USA). Hawaii Inst. of Geophysics); Colin, P.L. (Hawaii Inst. of Marine Biology, Honolulu (USA)); Buddemeier, R.W. (California Univ., Livermore (USA). Lawrence Livermore Lab.); Suchanek, T.H. (Fairleigh Dickinson Univ., St. Croix, Virgin Islands (USA). West Indies Lab.)

    1985-02-21

    The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. The authors report elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon.

  3. Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation

    International Nuclear Information System (INIS)

    McMurtry, G.M.; Schneider, R.C.; Buddemeier, R.W.; Suchanek, T.H.

    1985-01-01

    The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. The authors report elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon. (author)

  4. Variations of caesium isotope concentrations in air and fallout at Dalat, South Vietnam, 1986-1991

    International Nuclear Information System (INIS)

    Pham Zuy Hien; Nguyen Thanh Binh; Truong Y.; Vuong Thu Bac; Nguyen Trong Ngo.

    1993-01-01

    Monthly records of Cs-137 and Cs-134 concentrations in air and fallout at Dalat for the period 1986-1991 are presented and discussed. The concentration variations exhibit distinct maxima during December-January, when dry fallout dominated. These peaks are explained by the intrusion of more radioactive cold air masses from temperate northern latitudes during the development of large-scale anticyclones frequently observed in the most active winter monsoon period. High dry fallout velocities (about 10 cm/s) determined from this data clearly demonstrate one of the most relevant characteristics of cold air masses: behind the cold front, vertical air motion is descending

  5. Observations on the radioactive fallout originated from the reactor accident at Chernobyl in USSR, 1

    International Nuclear Information System (INIS)

    Morishima, Hiroshige; Koga, Taeko; Hisanaga, Saemi

    1986-01-01

    On 26 April a large amount of radioactive materials was accidentally released from the nuclear power station at Chernobyl in USSR. At the beginning of May the radioactivity was also detected at first at Chiba city in Japan, soon later at many places in country; the whole country was covered with radioactive plume transported from Chernobyl. In Higashi-Osaka city district radioactivity was found in air-borne dust at dawn of 4 May. The health physics group at Atomic Energy Research Institute of Kinki University in Osaka analysed γ and β radioactivities in a large amount of environmental samples, such as air-borne dust, rain water, vegetations, milk on the market, tap water and Biwa-lake water etc. Gamma-ray spectral analyses and gross β analyses were carried out for the above samples and nuclides of fission products such as 131 I, 132 I, 103 Ru, 106 Ru, 134 Cs, 137 Cs, 99 Mo( 99m Tc), 132 Te, 140 Ba and 140 La etc. were detected. Maximum 131 I concentrations in air-borne dust, rain water, milk on the market, tap water, vegetations and Biwa-lake water etc. were 2.45 pCi/m 3 (0.0907 Bq/m 3 ), 118 pCi/l (4.37 Bq/l), 91.4 pCi/l (3.38 Bq/l), 20 pCi/l (0.74 Bq/l), 7.9 x 10 3 pCi/kg fresh weight (292 Bq/kg fresh weight) and 0.81 pCi/l (0.0300 Bq/l), respectively. Thereafter average radioactivity concentrations in air-borne dust, rainwater, tap water and milk on the market etc. gradually declined to the normal value or below detectable limit. However, nuclides of long half-lives were expected to remain in vegetations and soils. After administration of 131 I through milk, the radioactivity concentration of which is 91 pCi/l (3.4 Bq/l), internal exposure is calculated to be 8.6 mrem/y (0.086 mSv/y), referring the guide-line issued by Japan Atomic Energy Commission for the purpose of exposure estimation near nuclear power stations. (J.P.N.)

  6. Biological pathways of radionuclides originating from the Chernobyl fallout in a boreal forest ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Guillitte, O. (Unite de Radioecologie, Faculte des Sciences Agronomiques, Gembloux (Belgium)); Melin, J.; Wallberg, L. (Swedish Radiation Protection Institute, Stockholm (Sweden))

    1994-10-14

    In an attempt to understand the mechanisms governing the transfer and retention of radiocaesium in the understorey vegetation, 39 macromycetes species and 33 plant species, together with humus samples, were systematically collected from the undercover vegetation in a boreal coniferous forest. The results indicate that the main factors determining interspecific differences in contamination level are the rooting depth in plants, the depth of mycelium in fungi, and the ecophysiological behaviour of fungi, mycotrophism or plant parasitism. A comparison between the investigated species and the same species growing in similar ecosystems, albeit under different climatic conditions, resulted in an almost identical ranking in terms of radiocaesium contamination levels; the contamination ratios between species were also relatively constant. From an experiment involving humus samples, it was shown that up to 40% of the radiocaesium could be retained by the microflora, particularly by mycelia.

  7. Autogenic dynamics of debris-flow fans

    Science.gov (United States)

    van den Berg, Wilco; de Haas, Tjalling; Braat, Lisanne; Kleinhans, Maarten

    2015-04-01

    Alluvial fans develop their semi-conical shape by cyclic avulsion of their geomorphologically active sector from a fixed fan apex. These cyclic avulsions have been attributed to both allogenic and autogenic forcings and processes. Autogenic dynamics have been extensively studied on fluvial fans through physical scale experiments, and are governed by cyclic alternations of aggradation by unconfined sheet flow, fanhead incision leading to channelized flow, channel backfilling and avulsion. On debris-flow fans, however, autogenic dynamics have not yet been directly observed. We experimentally created debris-flow fans under constant extrinsic forcings, and show that autogenic dynamics are a fundamental intrinsic process on debris-flow fans. We found that autogenic cycles on debris-flow fans are driven by sequences of backfilling, avulsion and channelization, similar to the cycles on fluvial fans. However, the processes that govern these sequences are unique for debris-flow fans, and differ fundamentally from the processes that govern autogenic dynamics on fluvial fans. We experimentally observed that backfilling commenced after the debris flows reached their maximum possible extent. The next debris flows then progressively became shorter, driven by feedbacks on fan morphology and flow-dynamics. The progressively decreasing debris-flow length caused in-channel sedimentation, which led to increasing channel overflow and wider debris flows. This reduced the impulse of the liquefied flow body to the flow front, which then further reduced flow velocity and runout length, and induced further in-channel sedimentation. This commenced a positive feedback wherein debris flows became increasingly short and wide, until the channel was completely filled and the apex cross-profile was plano-convex. At this point, there was no preferential transport direction by channelization, and the debris flows progressively avulsed towards the steepest, preferential, flow path. Simultaneously

  8. Sampling supraglacial debris thickness using terrestrial photogrammetry

    Science.gov (United States)

    Nicholson, Lindsey; Mertes, Jordan

    2017-04-01

    The melt rate of debris-covered ice differs to that of clean ice primarily as a function of debris thickness. The spatial distribution of supraglacial debris thickness must therefore be known in order to understand how it is likely to impact glacier behaviour, and meltwater contribution to local hydrological resources and global sea level rise. However, practical means of determining debris cover thickness remain elusive. In this study we explore the utility of terrestrial photogrammetry to produce high resolution, scaled and texturized digital terrain models of debris cover exposures above ice cliffs as a means of quantifying and characterizing debris thickness. Two Nikon D5000 DSLRs with Tamron 100mm lenses were used to photograph a sample area of the Ngozumpa glacier in the Khumbu Himal of Nepal in April 2016. A Structure from Motion workflow using Agisoft Photoscan software was used to generate a surface models with <10cm resolution. A Trimble Geo7X differential GPS with Zephyr antenna, along with a local base station, was used to precisely measure marked ground control points to scale the photogrammetric surface model. Measurements of debris thickness along the exposed cliffline were made from this scaled model, assuming that the ice surface at the debris-ice boundary is horizontal, and these data are compared to 50 manual point measurements along the same clifftops. We conclude that sufficiently high resolution photogrammetry, with precise scaling information, provides a useful means to determine debris thickness at clifftop exposures. The resolution of the possible measurements depends on image resolution, the accuracy of the ground control points and the computational capacity to generate centimetre scale surface models. Application of such techniques to sufficiently high resolution imagery from UAV-borne cameras may offer a powerful means of determining debris thickness distribution patterns over debris covered glacier termini.

  9. Sedimentology, Behavior, and Hazards of Debris Flows at Mount Rainier, Washington

    Science.gov (United States)

    Scott, K.M.; Vallance, J.W.; Pringle, P.T.

    1995-01-01

    Mount Rainier is potentially the most dangerous volcano in the Cascade Range because of its great height, frequent earthquakes, active hydrothermal system, and extensive glacier mantle. Many debris flows and their distal phases have inundated areas far from the volcano during postglacial time. Two types of debris flows, cohesive and noncohesive, have radically different origins and behavior that relate empirically to clay content. The two types are the major subpopulations of debris flows at Mount Rainier. The behavior of cohesive flows is affected by the cohesion and adhesion of particles; noncohesive flows are dominated by particle collisions to the extent that particle cataclasis becomes common during near-boundary shear. Cohesive debris flows contain more than 3 to 5 percent of clay-size sediment. The composition of these flows changed little as they traveled more than 100 kilometers from Mount Rainier to inundate parts of the now-populated Puget Sound lowland. They originate as deep-seated failures of sectors of the volcanic edifice, and such failures are sufficiently frequent that they are the major destructional process of Mount Rainier's morphologic evolution. In several deposits of large cohesive flows, a lateral, megaclast-bearing facies (with a mounded or hummocky surface) contrasts with a more clay-rich facies in the center of valleys and downstream. Cohesive flows at Mount Rainier do not correlate strongly with volcanic activity and thus can recur without warning, possibly triggered by non-magmatic earthquakes or by changes in the hydrothermal system. Noncohesive debris flows contain less than 3 to 5 percent clay-size sediment. They form most commonly by bulking of sediment in water surges, but some originate directly or indirectly from shallow slope failures that do not penetrate the hydrothermally altered core of the volcano. In contrast with cohesive flows, most noncohesive flows transform both from and to other flow types and are, therefore, the

  10. The Fabulous Four Debris Disks

    Science.gov (United States)

    Werner, Michael; Stapelfeldt, Karl

    2004-09-01

    This program is a comprehensive study of the four bright debris disks that were spatially resolved by IRAS: Beta Pictoris, Epsilon Eridani, Fomalhaut, and Vega. All SIRTF instruments and observing modes will be used. The program has three major objectives: (1) Study of the disk spatial structure from MIPS and IRAC imaging; (2) Study of the dust grain composition using the IRS and MIPS SED mode; and (3) companion searches using IRAC. The data from this program should lead to a detailed understanding of these four systems, and will provide a foundation for understanding all of the debris disks to be studied with SIRTF. Images and spectra will be compared with models for disk structure and dust properties. Dynamical features indicative of substellar companions' effects on the disks will be searched for. This program will require supporting observations of PSF stars, some of which have been included explicitly. In the majority of cases, the spectral observations require a preferred orientation to align the slits along the disk position angles. Detector saturation issues are still being worked for this program, and will lead to AOR modifications in subsequent submissions. The results from this program will be analyzed collaboratively by the IRAC, IRS, and MIPS teams and by general GTOs Jura and Werner.

  11. Graphic presentation of quarterly 90Sr fallout data, 1954-1982

    International Nuclear Information System (INIS)

    Larsen, R.J.

    1984-01-01

    This report graphically presents all of the precipitation and 90 Sr deposition data for all stations operated as part of the Environmental Measurements Laboratory's (EML) global fallout program since the initiation of the program in 1954. 3 references, 179 figures

  12. Influence of radioactive fallout on water supply and sewerage in Finland; Radioaktiivisen laskeuman vaikutukset vesihuoltoon

    Energy Technology Data Exchange (ETDEWEB)

    Rantavaara, A; Saxen, R; Puhakainen, M [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland); Hatva, T; Ahosilta, P; Tenhunen, J [National Board of Waters and the Environment, Helsinki (Finland)

    1995-09-01

    The report reviews the practices and organization of water supply and sewerage in Finland and is related to their response to radioactive fallout situations. The contribution of drinking water to the internal radiation dose caused by radioactive fallout has earlier been small in Finland. However, in a wide-scale fallout situation, the decreasing of collective dose received from water may be justified, if the dose can be reduced at a reasonable cost, for instance by a temporary change of the raw water source. Efficient exchange of information between radiation protection and water supply experts is important for successful dose reduction measures. In Finland waterworks deliver tap water to 4.2 million people. Half of the water is ground water, and generally very well protected against fallout radioactivity. The other half is treated surface water. (6 figs., 5 tabs.).

  13. Tephra Fallout Hazard Assessment for VEI5 Plinian Eruption at Kuju Volcano, Japan, Using TEPHRA2

    Science.gov (United States)

    Tsuji, Tomohiro; Ikeda, Michiharu; Kishimoto, Hiroshi; Fujita, Koji; Nishizaka, Naoki; Onishi, Kozo

    2017-06-01

    Tephra fallout has a potential impact on engineered structures and systems at nuclear power plants. We provide the first report estimating potential accumulations of tephra fallout as big as VEI5 eruption from Kuju Volcano and calculated hazard curves at the Ikata Power Plant, using the TEPHRA2 computer program. We reconstructed the eruptive parameters of Kj-P1 tephra fallout deposit based on geological survey and literature review. A series of parameter studies were carried out to determine the best values of empirical parameters, such as diffusion coefficient and the fall time threshold. Based on such a reconstruction, we represent probabilistic analyses which assess the variation in meteorological condition, using wind profiles extracted from a 22 year long wind dataset. The obtained hazard curves and probability maps of tephra fallout associated to a Plinian eruption were used to discuss the exceeding probability at the site and the implications of such a severe eruption scenario.

  14. Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation.

    Science.gov (United States)

    McMurtry, G M; Schneider, R C; Colin, P L; Buddemeier, R W; Suchanek, T H

    The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. Studies of the burial of fallout radionuclides have been conducted on the islands and in several of the large craters, but studies of their vertical distribution have been limited to about the upper 20 cm of the lagoon sediments. We have found elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon.

  15. On temporal variation of Ceasium isotopes activities in airborne and fallout

    International Nuclear Information System (INIS)

    Hien, P.D.; Binh, N.T.; Y, T.; Bac, V.T.; Ngo, N.T.; Luyen, T.V.

    1992-01-01

    Monthly variations of Cs-137 and Cs-134 activities in airborne and fallout collected in Dalat from 1986 to 1991 are presented. The variations exhibit distinct maxima in December-January, when dry fallout was predominant. The observed peaks are explained by the intrusion of cold air masses with higher radioactivity from temperate latitudes during the development of large-scale anticyclones frequently observed in the most active winter monsoon period. Very high dry fallout velocity (about 10 cm/s) determined from the airborne and fallout activities clearly demonstrates one of the most relevant characteristics of cold air masses: behind the cold front vertical air motion is descending.(Authors) (1 Fig. 2 Tables)

  16. Thyroid Nodules as a Late Effect of Exposure to Fallout

    Energy Technology Data Exchange (ETDEWEB)

    Conard, R. A. [Brookhaven National Laboratory, Upton, NY (United States); Sutow, W. W. [M.D. Anderson Hospital and Tumor Institute, Houston, TX (United States); Colcock, B. P. [Lahey Clinic, Boston, MA (United States); Dobyns, B. M. [Cleveland Metropolitan General Hospital, Cleveland, OH (United States); Paglia, D. E. [Center for the Health Sciences, University of California, Los Angeles, CA (United States)

    1969-11-15

    Multiple nodules of the thyroid gland have developed in a Marshallese population 10 to 14 years after accidental exposure to radioactive fallout The exposure occurred in 1954 when an unpredicted shift in winds caused deposition of fallout on several Marshall Islands east of Bikini Sixty four people received 175 rads of gamma radiation which proved to be sub lethal but resulted in early nausea and vomiting and significant depression of blood elements Exposure of the skin resulted m beta bums and epilation and there was significant internal absorption of fission isotopes from contaminated food and water The most serious internal exposure was from radioiodines ({sup 131}I {sup 132}I {sup 133}I {sup 135}I) It was estimated that in addition to the gamma radiation the adult thyroid gland received 160 rads from radioiodines and the young children because of their considerably smaller glands an estimated 700 1400 rads Recovery of blood elements to nearly normal and healing of skin lesions with regrowth of hair was complete by one year These findings have been fully documented The most important late radiation effect has been the development of thyroid abnormalities Since 1963 a total of 20 cases have thus far been detected 17 in children exposed at less than 10 years of age (90% of that group) and 3 in adults Thyroid surgery on 11 children and 3 adults revealed that all had benign adenomatous nodules except for a mixed papillary and follicular carcinoma in a 40 year-old woman The benign nodules were similar to those associated with iodine deficiency but such deficiency was not apparent m the Marshallese who live largely on seafood However most pathologists could not distinguish definite radiation effects in the nodules Growth and development retardation in some of the exposed children is now clearly related to thyroid deficiency Two boys with the greatest growth retardation developed pronounced hypothyroidism with atrophy of their thyroid glands Treatment of the exposed

  17. Debris flows: behavior and hazard assessment

    Science.gov (United States)

    Iverson, Richard M.

    2014-01-01

    Debris flows are water-laden masses of soil and fragmented rock that rush down mountainsides, funnel into stream channels, entrain objects in their paths, and form lobate deposits when they spill onto valley floors. Because they have volumetric sediment concentrations that exceed 40 percent, maximum speeds that surpass 10 m/s, and sizes that can range up to ~109 m3, debris flows can denude slopes, bury floodplains, and devastate people and property. Computational models can accurately represent the physics of debris-flow initiation, motion and deposition by simulating evolution of flow mass and momentum while accounting for interactions of debris' solid and fluid constituents. The use of physically based models for hazard forecasting can be limited by imprecise knowledge of initial and boundary conditions and material properties, however. Therefore, empirical methods continue to play an important role in debris-flow hazard assessment.

  18. Estimated inventory of plutonium and uranium radionuclides for vegetation in aged fallout areas

    International Nuclear Information System (INIS)

    Romney, E.M.; Wallace, A.; Kinnear, J.; Gilbert, R.O.

    1977-01-01

    Data are presented pertinent to the contamination of vegetation by plutonium and other radionuclides in aged fallout areas on the Nevada Test Site (NTS) and the Tonopah Test Range (TTR). The standing biomass of vegetation estimated by nondestructive dimensional methods varied from about 200 to 600 g/m 2 for the different fallout areas. Estimated inventories of 238 Pu, 239 Pu, 240 Pu, and 235 U in plants and their biological effects are discussed

  19. Fallout Deposition in the Marshall Islands from Bikini and Enewetak Nuclear Weapons Tests

    OpenAIRE

    Beck, Harold L.; Bouville, André; Moroz, Brian E.; Simon, Steven L.

    2010-01-01

    Deposition densities (Bq m-2) of all important dose-contributing radionuclides occurring in nuclear weapons testing fallout from tests conducted at Bikini and Enewetak Atolls (1946-1958) have been estimated on a test-specific basis for all the 31 atolls and separate reef islands of the Marshall Islands. A complete review of various historical and contemporary data, as well as meteorological analysis, was used to make judgments regarding which tests deposited fallout in the Marshall Islands an...

  20. Immobilisation of active concrete debris using soluble sodium silicates

    International Nuclear Information System (INIS)

    Field, S.N.; Jull, S.P.

    1991-01-01

    Demolition of concrete biological shields will generate large quantities of active demolition debris. The size distribution of such concrete may range from pieces of size less than one tonne down to dust. Handling and disposal methods for this material are still the subject of current research. Although the literature indicates that the mechanisms of silicate/concrete interaction are not well understood, successful setting of the smaller size fraction of concrete demolition debris can be achieved at laboratory scale. Hardened properties of the set slurry are also acceptable. A study of the full scale process has resulted in an outline design for a suitable on-site plant. Estimated capital costs of the equipment are of the order of pounds 1.1M. The project has shown that the material of less than 5mm particle size can be set by this technique. Whilst this meets the original objectives of immobilising dust, it had been hoped that the 10mm size material, (which will require removal from the larger debris before grouting can take place) could also be disposed of by the slurry setting technique. Co-disposal of slurry and large active items in the same container is unlikely to be worthwhile. 14 tabs., 5 figs., 30 refs

  1. What Sets the Radial Locations of Warm Debris Disks?

    Energy Technology Data Exchange (ETDEWEB)

    Ballering, Nicholas P.; Rieke, George H.; Su, Kate Y. L.; Gáspár, András, E-mail: ballerin@email.arizona.edu [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)

    2017-08-20

    The architectures of debris disks encode the history of planet formation in these systems. Studies of debris disks via their spectral energy distributions (SEDs) have found infrared excesses arising from cold dust, warm dust, or a combination of the two. The cold outer belts of many systems have been imaged, facilitating their study in great detail. Far less is known about the warm components, including the origin of the dust. The regularity of the disk temperatures indicates an underlying structure that may be linked to the water snow line. If the dust is generated from collisions in an exo-asteroid belt, the dust will likely trace the location of the water snow line in the primordial protoplanetary disk where planetesimal growth was enhanced. If instead the warm dust arises from the inward transport from a reservoir of icy material farther out in the system, the dust location is expected to be set by the current snow line. We analyze the SEDs of a large sample of debris disks with warm components. We find that warm components in single-component systems (those without detectable cold components) follow the primordial snow line rather than the current snow line, so they likely arise from exo-asteroid belts. While the locations of many warm components in two-component systems are also consistent with the primordial snow line, there is more diversity among these systems, suggesting additional effects play a role.

  2. Evaluation of detector responses to natural environmental and fall-out gamma radiation

    International Nuclear Information System (INIS)

    Arvela, H.

    1988-01-01

    Instrument responses to the thorium, uranium and potassium components of the natural environmental as well as the fall-out radiation field were evaluated. The responses to the 137 Cs fall-out radiation field differ by less than 6% from the response at 0.662 MeV, except for that of the NaI scintillator. Differences of more than 30% were found in the responses of two energy compensated instruments to normal natural background radiation and to radiation from fresh fall-out. The best estimate of the terrestrial component of the dose rate measured was obtained by carrying out the following corrections of the measured readings: cosmic ray contribution and internal background subtraction with response correction, including 137 Cs calibration correction. After the Chernobyl accident the dose rate levels due to 137 Cs and 134 Cs fall-out were comparable to the natural background gamma radiation. The responses calculated as well as the results from measurements of the low level environmental exposure levels caused by the Chernobyl fall-out, confirmed the need to take into account the instrument response to natural as well as fall-out radiation fields. (author)

  3. Alimentary tract absorption (f1 values) for radionuclides in local and regional fallout from nuclear tests.

    Science.gov (United States)

    Ibrahim, Shawki A; Simon, Steven L; Bouville, André; Melo, Dunstana; Beck, Harold L

    2010-08-01

    This paper presents gastrointestinal absorption fractions (f1 values) for estimating internal doses from local and regional fallout radionuclides due to nuclear tests. The choice of f1 values are based on specific circumstances of weapons test conditions and a review of reported f1 values for elements in different physical and chemical states. Special attention is given to fallout from nuclear tests conducted at the Marshall Islands. We make a distinction between the f1 values for intakes of radioactive materials immediately after deposition (acute intakes) and intakes that occur in the course of months and years after deposition, following incorporation into terrestrial and aquatic foodstuffs (chronic intakes). Multiple f1 values for different circumstances where persons are exposed to radioactive fallout (e.g., local vs. regional fallout and coral vs. continental tests) are presented when supportive information is available. In some cases, our selected f1 values are similar to those adopted by the International Commission on Radiological Protection (ICRP) (e.g., iodine and most actinides). However, f1 values for cesium and strontium derived from urine bioassay data of the Marshallese population are notably lower than the generic f1 values recommended by ICRP, particularly for acute intakes from local fallout (0.4 and 0.05 for Cs and Sr, respectively). The f1 values presented here form the first complete set of values relevant to realistic dose assessments for exposure to local or regional radioactive fallout.

  4. The Inner 25 au Debris Distribution in the ϵ Eri System

    Energy Technology Data Exchange (ETDEWEB)

    Su, Kate Y. L.; Rieke, George H.; Ballering, Nicholas P. [Steward Observatory, University of Arizona, 933 N Cherry Avenue, Tucson, AZ 85721 (United States); De Buizer, James M.; Vacca, William D. [SOFIA-USRA, NASA Ames Research Center, MS 232-12, Moffett Field, CA 94035 (United States); Krivov, Alexander V.; Löhne, Torsten [Astrophysikalisches Institut und Universitätssternwarte, Friedrich-Schiller-Universität Jena, Schillergäßchen 2–3, D-07745 Jena (Germany); Marengo, Massimo [Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Stapelfeldt, Karl R. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)

    2017-05-01

    Debris disk morphology is wavelength dependent due to the wide range of particle sizes and size-dependent dynamics influenced by various forces. Resolved images of nearby debris disks reveal complex disk structures that are difficult to distinguish from their spectral energy distributions. Therefore, multi-wavelength resolved images of nearby debris systems provide an essential foundation to understand the intricate interplay between collisional, gravitational, and radiative forces that govern debris disk structures. We present the Stratospheric Observatory for Infrared Astronomy (SOFIA) 35 μ m resolved disk image of ϵ Eri, the closest debris disk around a star similar to the early Sun. Combining with the Spitzer resolved image at 24 μ m and 15–38 μ m excess spectrum, we examine two proposed origins of the inner debris in ϵ Eri: (1) in situ planetesimal belt(s) and (2) dragged-in grains from the cold outer belt. We find that the presence of in situ dust-producing planetesmial belt(s) is the most likely source of the excess emission in the inner 25 au region. Although a small amount of dragged-in grains from the cold belt could contribute to the excess emission in the inner region, the resolution of the SOFIA data is high enough to rule out the possibility that the entire inner warm excess results from dragged-in grains, but not enough to distinguish one broad inner disk from two narrow belts.

  5. KFM: a homemade yet accurate and dependable fallout meter

    International Nuclear Information System (INIS)

    Kearny, C.H.; Barnes, P.R.; Chester, C.V.; Cortner, M.W.

    1978-01-01

    The KFM is a homemade fallout meter that can be made using only materials, tools, and skills found in millions of American homes. It is an accurate and dependable electroscope-capacitor. The KFM, in conjunction with its attached table and a watch, is designed for use as a rate meter. Its attached table relates observed differences in the separations of its two leaves (before and after exposures at the listed time intervals) to the dose rates during exposures of these time intervals. In this manner dose rates from 30 mR/hr up to 43 R/hr can be determined with an accuracy of +-25%. A KFM can be charged with any one of the three expedient electrostatic charging devices described. Due to the use of anhydrite (made by heating gypsum from wallboard) inside a KFM and the expedient ''dry-bucket'' in which it can be charged when the air is very humid, this instrument always can be charged and used to obtain accurate measurements of gamma radiation no matter how high the relative humidity. The step-by-step illustrated instructions for making and using a KFM are presented. These instructions have been improved after each successive field test. The majority of the untrained test families, adequately motivated by cash bonuses offered for success and guided only by these written instructions, have succeeded in making and using a KFM

  6. Fallout plutonium in two oxic-anoxic environments

    International Nuclear Information System (INIS)

    Sanchez, A.L.; Murray, J.W.; Schell, W.R.; Miller, L.G.

    1986-01-01

    The profiles of soluble fallout plutonium in two partially anoxic waters revealed minimum concentrations at the O 2 -H 2 S interface, indicating Pu removal onto particulate phases of Fe and other oxidized species that form during the redox cycle. In Saanich Inlet, an intermittently anoxic fjord in Vancouver Island, Canada, the concentration of soluble Pu in the anoxic zone was slightly less than in the oxygenated surface layer. In Soap Lake, a saline meromictic lake in eastern Washington State, Pu concentrations i the permanently anoxic zone were at least an order of magnitude higher than at the surface. Differences in the chemical characteristics of these two waters suggest important chemical species that influenced the observed Pu distribution. In the permanently anoxic zone of Soap Lake, high values of total alkalinity ranging from 940 to 1500 meq liter -1 , sulfide species from 38 to 128 μM, dissolved organic carbon from 163 to 237 mg liter -1 , and total dissolved solids from 80 to 140 ppt, all correlated with the observed high concentration of Pu. In Saanich Inlet, where total alkalinity ranged from 2.1 to 2.4 meq liter -1 and salinity from 25 to 32 per thousand and H 2 S concentration in May 1981 showed a maximum of 8μM, the observed Pu concentrations were significantly lower than for the Soap Lake monimolimnion

  7. Atmospheric fallout radionuclides in peatland from Southern Poland.

    Science.gov (United States)

    Mróz, Tomasz; Łokas, Edyta; Kocurek, Justyna; Gąsiorek, Michał

    2017-09-01

    Two peat profiles were collected in a peat bog located in Southern Poland and their geochronology were determined using 210 Pb, 238,239+240 Pu and 137 Cs radiometric techniques. The 210 Pb chronologies were established using the constant rate of supply model (CRS) and are in good agreement with the Pu isotopes and 137 Cs time markers. Maximum activities of Pu isotopes were found at a depth corresponding to the early 1960s, which is the period characterized by the maximum nuclear weapon tests. The results showed that the 210 Pb method is the most accurate technique for the determination age and accumulation rate of a peat. The next part of this study calculated linear accumulation rates by analyzing 238,239+240 Pu and 137 Cs vertical distributions in the profiles. Activities of fallout isotopes were also measured in plants covering the peatland. The highest activities of 137 Cs and 210 Pb were found in Calluna vulgaris samples, and 239+240 Pu were found only in two samples (C. vulgaris and leaves of Oxycoccus quadripelatus). Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Neonatal outcomes following exposure in utero to fallout from Chernobyl.

    Science.gov (United States)

    Hatch, Maureen; Little, Mark P; Brenner, Alina V; Cahoon, Elizabeth K; Tereshchenko, Valery; Chaikovska, Ludmyla; Pasteur, Igor; Likhtarov, Ilya; Bouville, Andre; Shpak, Victor; Bolshova, Olena; Zamotayeva, Galyna; Grantz, Katherine; Sun, Liping; Mabuchi, Kiyohiko; Albert, Paul; Tronko, Mykola

    2017-12-01

    Iodine 131 (I-131), the principal component of nuclear fallout from the Chernobyl accident, concentrates in the thyroid gland and may pose risks to fetal development. To evaluate this, neonatal outcomes following the accident in April of 1986 were investigated in a cohort of 2582 in utero-exposed individuals from northern Ukraine for whom estimates of fetal thyroid I-131 dose were available. We carried out a retrospective review of cohort members' prenatal, delivery and newborn records. The relationships of dose with neonatal anthropometrics and gestational length were modeled via linear regression with adjustment for potentially confounding variables. We found similar, statistically significant dose-dependent reductions in both head circumference (-1.0 cm/Gy, P = 0.005) and chest circumference (-0.9 cm/Gy, P = 0.023), as well as a similar but non-significant reduction in neonatal length (-0.6 cm/Gy, P = 0.169). Gestational length was significantly increased with increasing fetal dose (0.5 wks/Gy, P = 0.007). There was no significant (P > 0.1) effect of fetal dose on birth weight. The observed associations of radioiodine exposure with decreased head and chest circumference are consistent with those observed in the Japanese in utero-exposed atomic bomb survivors.

  9. Radiocaesium fallout in Ireland from the Chernobyl accident

    International Nuclear Information System (INIS)

    McAulay, I.R.; Moran, D.

    1989-01-01

    This paper presents a radiocaesium deposition pattern over Ireland resulting from the Chernobyl accident. Contaminated grassland soils from over 110 sites were analysed using gamma ray spectrometry. 134 Cs, 137 Cs and 40 K were measured in all samples. The Chernobyl 137 Cs was identified using an initial Chernobyl fallout 137 Cs to 134 Cs ratio of 1.90. The results show a mean deposition level of 3.2 kBq m -2 of 137 Cs due to Chernobyl. The range of deposition was from 0.3 to 14.2 kBq m -2 . The distribution pattern is presented both on a National grid sub-zone basis and a higher resolution shaded map. A similarly shaded map shows the rainfall levels responsible for most of the washout. It is pointed out that some areas on both east and west coasts with maximum rainfall did not have maximum caesium deposition. In other areas a better correlation between rainfall and caesium deposition exists. A mean figure for the pre-Chernobyl 137 Cs in surface soil is provided. (author)

  10. Cancer mortality and radioactive fallout in southwestern Utah

    International Nuclear Information System (INIS)

    Machado, S.G.; Land, C.E.; McKay, F.W.

    1987-01-01

    Cancer mortality was compared between a three-county region in southwestern Utah and the remainder of Utah in an investigation of reported excess cancer risks associated with residence in southwestern Utah during the period of above-ground nuclear tests at the Nevada Test Site. Because most of the fallout in southwestern Utah was deposited during 1953-1957, comparisons were limited to persons born before 1958, and deaths from leukemia and bone cancer during 1955-1980 and from other cancers during 1964-1980. There was no excess risk of cancer mortality in southwestern Utah, for single or grouped sites, with the single exception of leukemia which showed statistically significant odds ratios of 1.45 based on 62 deaths at all ages, and 2.84 based on nine deaths at ages 0-14. The finding for childhood leukemia was based on different time periods and geographic comparisons from those of two earlier studies in which no such excess was found. Mortality from all cancer sites combined was significantly lower in southwestern Utah than in the remainder of the state, even after adjustment for the higher proportion of (lower risk) Mormons in southwestern Utah. The present results, including the positive association for leukemia, are inconsistent with the high excess risks reported by Johnson (JAMA 1984;251:230-6) based on an interview survey of cancer incidence among long-term Mormon residents of southwestern Utah

  11. Beyond eruptive scenarios: assessing tephra fallout hazard from Neapolitan volcanoes.

    Science.gov (United States)

    Sandri, Laura; Costa, Antonio; Selva, Jacopo; Tonini, Roberto; Macedonio, Giovanni; Folch, Arnau; Sulpizio, Roberto

    2016-04-12

    Assessment of volcanic hazards is necessary for risk mitigation. Typically, hazard assessment is based on one or a few, subjectively chosen representative eruptive scenarios, which use a specific combination of eruptive sizes and intensities to represent a particular size class of eruption. While such eruptive scenarios use a range of representative members to capture a range of eruptive sizes and intensities in order to reflect a wider size class, a scenario approach neglects to account for the intrinsic variability of volcanic eruptions, and implicitly assumes that inter-class size variability (i.e. size difference between different eruptive size classes) dominates over intra-class size variability (i.e. size difference within an eruptive size class), the latter of which is treated as negligible. So far, no quantitative study has been undertaken to verify such an assumption. Here, we adopt a novel Probabilistic Volcanic Hazard Analysis (PVHA) strategy, which accounts for intrinsic eruptive variabilities, to quantify the tephra fallout hazard in the Campania area. We compare the results of the new probabilistic approach with the classical scenario approach. The results allow for determining whether a simplified scenario approach can be considered valid, and for quantifying the bias which arises when full variability is not accounted for.

  12. Retrospective evaluation of tritium fallout by tree-ring analysis

    International Nuclear Information System (INIS)

    Kozak, K.; Biro, T.; Golder, F.; Rank, D.; Rajner, V.; Staudner, F.

    1993-01-01

    Tritium analyses of tree-ring cellulose were made to test its suitability for retrospective evaluation of a local tritium fallout. Several spruce trees were taken from an Austrian alpine area where tritium contamination of May 1974 precipitation had been detected. Wood from the annual growth rings of 1973, 1974 and 1975 was separated and the cellulose extracted. After isotopic equilibration with dead water, cellulose was combusted to yield water, whose tritium concentration was measured by liquid scintillation counting. Rigorous statistical treatment proved the significance of the increased tritium concentration caused by the tritium anomaly, which occurred during the growing season. The long-term trends of local atmospheric tritium, including the 1974 peak, were also well reflected by analysis of a 24-year ring sequence from a single tree in the contaminated area. The tritium data gained by the given method can be used at present qualitatively and a better understanding of the possible sources of contamination is required in order that the quantitative criteria be satisfied. (Author)

  13. Analysis of the Herschel DEBRIS Sun-like star sample

    Science.gov (United States)

    Sibthorpe, B.; Kennedy, G. M.; Wyatt, M. C.; Lestrade, J.-F.; Greaves, J. S.; Matthews, B. C.; Duchêne, G.

    2018-04-01

    This paper presents a study of circumstellar debris around Sun-like stars using data from the Herschel DEBRIS Key Programme. DEBRIS is an unbiased survey comprising the nearest ˜90 stars of each spectral type A-M. Analysis of the 275 F-K stars shows that excess emission from a debris disc was detected around 47 stars, giving a detection rate of 17.1^{+2.6}_{-2.3} per cent, with lower rates for later spectral types. For each target a blackbody spectrum was fitted to the dust emission to determine its fractional luminosity and temperature. The derived underlying distribution of fractional luminosity versus blackbody radius in the population showed that most detected discs are concentrated at f ˜ 10-5 and at temperatures corresponding to blackbody radii 7-40 au, which scales to ˜40 au for realistic dust properties (similar to the current Kuiper belt). Two outlying populations are also evident; five stars have exceptionally bright emission ( f > 5 × 10-5), and one has unusually hot dust <4 au. The excess emission distributions at all wavelengths were fitted with a steady-state evolution model, showing that these are compatible with all stars being born with a narrow belt that then undergoes collisional grinding. However, the model cannot explain the hot dust systems - likely originating in transient events - and bright emission systems - arising potentially from atypically massive discs or recent stirring. The emission from the present-day Kuiper belt is predicted to be close to the median of the population, suggesting that half of stars have either depleted their Kuiper belts (similar to the Solar system) or had a lower planetesimal formation efficiency.

  14. Porous Chromatographic Materials as Substrates for Preparing Synthetic Nuclear Explosion Debris Particles

    International Nuclear Information System (INIS)

    Harvey, Scott D.; Liezers, Martin; Antolick, Kathryn C.; Garcia, Ben J.; Sweet, Lucas E.; Carman, April J.; Eiden, Gregory C.

    2013-01-01

    In this study, we investigated several porous chromatographic materials as synthetic substrates for preparing surrogate nuclear explosion debris particles. The resulting synthetic debris materials are of interest for use in developing analytical methods. Eighteen metals, including some of forensic interest, were loaded onto materials by immersing them in metal solutions (556 mg/L of each metal) to fill the pores, applying gentle heat (110°C) to drive off water, and then treating them at high temperatures (up to 800°C) in air to form less soluble metal species. High-boiling-point metals were uniformly loaded on spherical controlled-pore glass to emulate early fallout, whereas low-boiling-point metals were loaded on core-shell silica to represent coated particles formed later in the nuclear fallout-formation process. Analytical studies were applied to characterize solubility, material balance, and formation of recalcitrant species. Dissolution experiments indicated loading was 1.5 to 3 times higher than expected from the pore volume alone, a result attributed to surface coating. Analysis of load solutions before and after filling the material pores revealed that most metals were passively loaded; that is, solutions filled the pores without active metal discrimination. However, niobium and tin concentrations were lower in solutions after pore filling, and were found in elevated concentrations in the final products, indicating some metals were selectively loaded. High-temperature treatments caused reduced solubility of several metal species, and loss of some metals (rhenium and tellurium) because volatile species were formed. Sample preparation reproducibility was high (the inter-batch relative standard deviation was 7.8%, and the intra-batch relative standard deviation was 0.84%) indicating that this material is suitable for use as a working standard for analytical methods development. We anticipate future standardized radionuclide-loaded materials will find use in

  15. Space Debris Removal: A Game Theoretic Analysis

    Directory of Open Access Journals (Sweden)

    Richard Klima

    2016-08-01

    Full Text Available We analyse active space debris removal efforts from a strategic, game-theoretical perspective. Space debris is non-manoeuvrable, human-made objects orbiting Earth, which pose a significant threat to operational spacecraft. Active debris removal missions have been considered and investigated by different space agencies with the goal to protect valuable assets present in strategic orbital environments. An active debris removal mission is costly, but has a positive effect for all satellites in the same orbital band. This leads to a dilemma: each agency is faced with the choice between the individually costly action of debris removal, which has a positive impact on all players; or wait and hope that others jump in and do the ‘dirty’ work. The risk of the latter action is that, if everyone waits, the joint outcome will be catastrophic, leading to what in game theory is referred to as the ‘tragedy of the commons’. We introduce and thoroughly analyse this dilemma using empirical game theory and a space debris simulator. We consider two- and three-player settings, investigate the strategic properties and equilibria of the game and find that the cost/benefit ratio of debris removal strongly affects the game dynamics.

  16. Orbital Debris and NASA's Measurement Program

    Science.gov (United States)

    Africano, J. L.; Stansbery, E. G.

    2002-05-01

    Since the launch of Sputnik in 1957, the number of manmade objects in orbit around the Earth has dramatically increased. The United States Space Surveillance Network (SSN) tracks and maintains orbits on over nine thousand objects down to a limiting diameter of about ten centimeters. Unfortunately, active spacecraft are only a small percentage ( ~ 7%) of this population. The rest of the population is orbital debris or ``space junk" consisting of expended rocket bodies, dead payloads, bits and pieces from satellite launches, and fragments from satellite breakups. The number of these smaller orbital debris objects increases rapidly with decreasing size. It is estimated that there are at least 130,000 orbital debris objects between one and ten centimeters in diameter. Most objects smaller than 10 centimeters go untracked! As the orbital debris population grows, the risk to other orbiting objects, most importantly manned space vehicles, of a collision with a piece of debris also grows. The kinetic energy of a solid 1 cm aluminum sphere traveling at an orbital velocity of 10 km/sec is equivalent to a 400 lb. safe traveling at 60 mph. Fortunately, the volume of space in which the orbiting population resides is large, collisions are infrequent, but they do occur. The Space Shuttle often returns to earth with its windshield pocked with small pits or craters caused by collisions with very small, sub-millimeter-size pieces of debris (paint flakes, particles from solid rocket exhaust, etc.), and micrometeoroids. To get a more complete picture of the orbital-debris environment, NASA has been using both radar and optical techniques to monitor the orbital debris environment. This paper gives an overview of the orbital debris environment and NASA's measurement program.

  17. POST Earthquake Debris Management — AN Overview

    Science.gov (United States)

    Sarkar, Raju

    Every year natural disasters, such as fires, floods, earthquakes, hurricanes, landslides, tsunami, and tornadoes, challenge various communities of the world. Earthquakes strike with varying degrees of severity and pose both short- and long-term challenges to public service providers. Earthquakes generate shock waves and displace the ground along fault lines. These seismic forces can bring down buildings and bridges in a localized area and damage buildings and other structures in a far wider area. Secondary damage from fires, explosions, and localized flooding from broken water pipes can increase the amount of debris. Earthquake debris includes building materials, personal property, and sediment from landslides. The management of this debris, as well as the waste generated during the reconstruction works, can place significant challenges on the national and local capacities. Debris removal is a major component of every post earthquake recovery operation. Much of the debris generated from earthquake is not hazardous. Soil, building material, and green waste, such as trees and shrubs, make up most of the volume of earthquake debris. These wastes not only create significant health problems and a very unpleasant living environment if not disposed of safely and appropriately, but also can subsequently impose economical burdens on the reconstruction phase. In practice, most of the debris may be either disposed of at landfill sites, reused as materials for construction or recycled into useful commodities Therefore, the debris clearance operation should focus on the geotechnical engineering approach as an important post earthquake issue to control the quality of the incoming flow of potential soil materials. In this paper, the importance of an emergency management perspective in this geotechnical approach that takes into account the different criteria related to the operation execution is proposed by highlighting the key issues concerning the handling of the construction

  18. POST Earthquake Debris Management - AN Overview

    Science.gov (United States)

    Sarkar, Raju

    Every year natural disasters, such as fires, floods, earthquakes, hurricanes, landslides, tsunami, and tornadoes, challenge various communities of the world. Earthquakes strike with varying degrees of severity and pose both short- and long-term challenges to public service providers. Earthquakes generate shock waves and displace the ground along fault lines. These seismic forces can bring down buildings and bridges in a localized area and damage buildings and other structures in a far wider area. Secondary damage from fires, explosions, and localized flooding from broken water pipes can increase the amount of debris. Earthquake debris includes building materials, personal property, and sediment from landslides. The management of this debris, as well as the waste generated during the reconstruction works, can place significant challenges on the national and local capacities. Debris removal is a major component of every post earthquake recovery operation. Much of the debris generated from earthquake is not hazardous. Soil, building material, and green waste, such as trees and shrubs, make up most of the volume of earthquake debris. These wastes not only create significant health problems and a very unpleasant living environment if not disposed of safely and appropriately, but also can subsequently impose economical burdens on the reconstruction phase. In practice, most of the debris may be either disposed of at landfill sites, reused as materials for construction or recycled into useful commodities Therefore, the debris clearance operation should focus on the geotechnical engineering approach as an important post earthquake issue to control the quality of the incoming flow of potential soil materials. In this paper, the importance of an emergency management perspective in this geotechnical approach that takes into account the different criteria related to the operation execution is proposed by highlighting the key issues concerning the handling of the construction

  19. Design of full scale debris washing system

    International Nuclear Information System (INIS)

    Taylor, M.L.; Dosani, M.A.; Wentz, J.A.; Patkar, A.N.; Barkley, N.P.

    1992-01-01

    Since 1987, IT Environmental Programs Inc. (ITEP, a subsidiary of International Technology Corporation) in conjunction with EPA/RREL in Cincinnati, Ohio, have been developing and conducting bench scale and pilot scale testing of a transportable debris washing system which can be used on-site for the decontamination of debris. During the initial phase of the debris decontamination project, a series of bench scale tests were performed in the laboratory to assess the ability of the system to remove contaminants from debris and to facilitate selection of the most efficient surfactant solution. Five nonionic, non-toxic, low foaming, surfactant solution (BG-5, MC-2000, LF-330, BB-100, and L-433) were selected for an experimental evaluation to determine their capacity to solubilize and remove contaminants from the surfaces of corroded steel places. The pieces of corroded steel were coated with a heavy grease mixture prepared in the laboratory and these pieces of debris were placed in a bench scale spray tank on a metal tray and subjected in a high-pressure spray for each surfactant solution for 15 minutes. At the end of the spray cycle, The tray was transferred to a second bench scale system, a high-turbulence wash tank, where the debris was washed for 30 minutes with the same surfactant solution as the used in the spray tank. After the was cycle was completed, the tray was removed from the wash tank and the debris was allowed to air-dry. Before and after treatment, surface-wipe samples were obtained from each of the six pieces of debris and were analyzed for oil and graese. Based on the results, BG-5 was selected as the solution best suited for cleaning grease-laden, metallic debris. 2 refs

  20. The Time-Frequency Signatures of Advanced Seismic Signals Generated by Debris Flows

    Science.gov (United States)

    Chu, C. R.; Huang, C. J.; Lin, C. R.; Wang, C. C.; Kuo, B. Y.; Yin, H. Y.

    2014-12-01

    The seismic monitoring is expected to reveal the process of debris flow from the initial area to alluvial fan, because other field monitoring techniques, such as the video camera and the ultrasonic sensor, are limited by detection range. For this reason, seismic approaches have been used as the detection system of debris flows over the past few decades. The analysis of the signatures of the seismic signals in time and frequency domain can be used to identify the different phases of debris flow. This study dedicates to investigate the different stages of seismic signals due to debris flow, including the advanced signal, the main front, and the decaying tail. Moreover, the characteristics of the advanced signals forward to the approach of main front were discussed for the warning purpose. This study presents a permanent system, composed by two seismometers, deployed along the bank of Ai-Yu-Zi Creek in Nantou County, which is one of the active streams with debris flow in Taiwan. The three axes seismometer with frequency response of 7 sec - 200 Hz was developed by the Institute of Earth Sciences (IES), Academia Sinica for the purpose to detect debris flow. The original idea of replacing the geophone system with the seismometer technique was for catching the advanced signals propagating from the upper reach of the stream before debris flow arrival because of the high sensitivity. Besides, the low frequency seismic waves could be also early detected because of the low attenuation. However, for avoiding other unnecessary ambient vibrations, the sensitivity of seismometer should be lower than the general seismometer for detecting teleseism. Three debris flows with different mean velocities were detected in 2013 and 2014. The typical triangular shape was obviously demonstrated in time series data and the spectrograms of the seismic signals from three events. The frequency analysis showed that enormous debris flow bearing huge boulders would induce low frequency seismic

  1. Apparatus for controlling nuclear core debris

    International Nuclear Information System (INIS)

    Jones, R.D.

    1978-01-01

    Disclosed is an apparatus for containing, cooling, and dispersing reactor debris assumed to flow from the core area in the unlikely event of an accident causing core meltdown. The apparatus includes a plurality of horizontally disposed vertically spaced plates, having depressions to contain debris in controlled amounts, and a plurality of holes therein which provide natural circulation cooling and a path for debris to continue flowing downward to the plate beneath. The uppermost plates may also include generally vertical sections which form annular-like flow areas which assist the natural circulation cooling

  2. Apparatus for controlling nuclear core debris

    Science.gov (United States)

    Jones, Robert D.

    1978-01-01

    Nuclear reactor apparatus for containing, cooling, and dispersing reactor debris assumed to flow from the core area in the unlikely event of an accident causing core meltdown. The apparatus includes a plurality of horizontally disposed vertically spaced plates, having depressions to contain debris in controlled amounts, and a plurality of holes therein which provide natural circulation cooling and a path for debris to continue flowing downward to the plate beneath. The uppermost plates may also include generally vertical sections which form annular-like flow areas which assist the natural circulation cooling.

  3. Development of debris resistant bottom end piece

    International Nuclear Information System (INIS)

    Lee, Jae Kyung; Sohn, Dong Seong; Yim, Jeong Sik; Hwang, Dae Hyun; Song, Kee Nam; Oh, Dong Seok; Rhu, Ho Sik; Lee, Chang Woo; Kim, Seong Soo; Oh, Jong Myung

    1993-12-01

    Debris-related fuel failures have been identified as one of the major causes of fuel failures. In order to reduce the possibility of debris-related fuel failures, it is necessary to develop Debris-Resistant Bottom End Piece. For this development, mechanical strength test and pressure drop test were performed, and the test results were analyzed. And the laser cutting, laser welding and electron beam welding technology, which were the core manufacturing technology of DRBEP, were developed. Final design were performed, and the final drawing and specifications were prepared. The prototype of DRBEP was manufactured according to the developed munufacturing procedure. (Author)

  4. Laser ignition of traumatically embedded firework debris.

    Science.gov (United States)

    Taylor, C R

    1998-01-01

    The Q-switched ruby laser (QSRL) has a good track record for traumatic tattoo removal. An unusual case of QSRL-treatment of a traumatic tattoo composed of firework debris is presented. A young man's traumatic tattoo, composed of firework debris, underwent QSRL ablation at 4-7 J/cm2 (pulse width 5 mm; duration 20 ns). Each test pulse produced visible sparks and focal projectile ejection of skin with pox-like scar formation. Caution is advised when using the QSRL for the treatment of traumatic tattoos composed of potentially combustible debris.

  5. Algorithms for the Computation of Debris Risk

    Science.gov (United States)

    Matney, Mark J.

    2017-01-01

    Determining the risks from space debris involve a number of statistical calculations. These calculations inevitably involve assumptions about geometry - including the physical geometry of orbits and the geometry of satellites. A number of tools have been developed in NASA’s Orbital Debris Program Office to handle these calculations; many of which have never been published before. These include algorithms that are used in NASA’s Orbital Debris Engineering Model ORDEM 3.0, as well as other tools useful for computing orbital collision rates and ground casualty risks. This paper presents an introduction to these algorithms and the assumptions upon which they are based.

  6. Algorithms for the Computation of Debris Risks

    Science.gov (United States)

    Matney, Mark

    2017-01-01

    Determining the risks from space debris involve a number of statistical calculations. These calculations inevitably involve assumptions about geometry - including the physical geometry of orbits and the geometry of non-spherical satellites. A number of tools have been developed in NASA's Orbital Debris Program Office to handle these calculations; many of which have never been published before. These include algorithms that are used in NASA's Orbital Debris Engineering Model ORDEM 3.0, as well as other tools useful for computing orbital collision rates and ground casualty risks. This paper will present an introduction to these algorithms and the assumptions upon which they are based.

  7. Gamma radiation and gamma ray protection factors of ships in various situations of radioactive fall-out

    International Nuclear Information System (INIS)

    Brehm, E.H.; Holst, T.

    1975-01-01

    In this report the development of methods of evaluating gamma ray protection factors (GSF) of ships for various situations of radioactive fall-out is described. The joining calculations of gamma ray protection factors are performed by the newly developed computer procedure GASUFA. These protection factors determine - in connection with a measured gamma radiation dose at a given detector point - the gamma radiation in different compartments of the ships. The computer program GASUFA is able to perform calculations considering the dependence of energy, place and time for the following situations: - the ship is under a radioactive cloud without fall-out; - the ship is under a radioactive cloud with fall-out; - the ship is contaminated by radioactive fall-out; - the clean or decontaminated ship is going through a zone, which is contaminated by radioactive fall-out; - the ship and the surrounding water surface are contaminated by radioactive fall-out. (orig.) [de

  8. Improving weapons fallout time series on a global basis using precipitation data

    International Nuclear Information System (INIS)

    Palsson, S.E.; Howard, B.J.; Aoyama, M.

    2004-01-01

    The fallout from the atmospheric weapons tests in the late fifties and early sixties forms the main source of man made radionuclides in the terrestrial environment. It is important to be able to distinguish global fallout from other sources of man-made radioactivity, and therefore to have good methods of quantifying the level of global fallout in areas where it has not previously been measured. Because global fallout was deposited over many years, model validation can require knowledge about deposition time series which are not available through direct measurements. This can be especially important for sparsely populated areas with vulnerable ecosystems, where high transfer of radionuclides, particularly radiocaesium, may occur. The UNSCEAR reports describe the global data and show how the deposition was dependent on latitude. Others have successfully used a model assuming a proportional relationship between deposition and precipitation (e.g. on a regional scale within the AMAP project and on a local scale in some countries, such as Iceland and Sweden). This paper describes a study where different data sets were combined to test, at a local scale to a global scale, how well the proportional relationship between precipitation and deposition holds and to what degree other effects (e.g. dependence on latitude as in the UNSCEAR model) need to be taken into account. It makes use of the Integrated Global Fallout Database of the Meteorological Research Institute of Japan which has been used previously to demonstrate the relationship between precipitation and deposition and subsequently to make an estimate of the total fallout amount of 137 Cs in the mid latitudes of the Northern Hemisphere. The study described in this paper provides a fuller description of global deposition than the latitude or precipitation based studies alone. Applied in a simple model as presented here, this enable better deposition estimation (including time dependency), especially if precipitation

  9. Development of debris-resistant bottom end piece

    International Nuclear Information System (INIS)

    Sohn, Dong Seong; Lee, Jae Kyung; Hwang, Dae Hyun; Yim, Jung Sik; Song, Kee Nam; Oh, Dong Seok; Im, Hyun Tae

    1993-01-01

    Debris-related fuel failures has been identified to be one of the major causes of fuel failures recently occured in nuclear power plants. In order to reduce the possibility of debris-related fuel failures, it is necessary to prevent the debris from reaching to fuel rods. In this regard, it is important to develop Debris-Resistant Bottom End Piece. (Author)

  10. Fallout Radionuclides as Tracers in Southern Alps Sediment Studies

    Science.gov (United States)

    Carey, A. E.; Karanovic, Z.; Dibb, J. E.

    2005-12-01

    The primary geologic processes shaping the landscape are physical and chemical weathering and the transport of solids by erosion. As part of our studies on the coupling between physical erosion and chemical weathering, we have determined depositional and erosional processes in New Zealand's tectonically active, rapidly uplifting Southern Alps, specifically focusing on the Hokitika River watershed. The South Island watersheds we are studying are subject to extreme orographic precipitation (as high as 7-12 m annually) and high landslide frequency, but have modest topography due to the rapid erosion. In concert with our studies of chemical weathering and physical erosion, we have used the atmospherically-delivered radionuclides of 7Be, 137Cs and 210Pbexcess to determine the relative magnitude of particle residence time in the high elevation Cropp and Whitcombe subwatersheds and the rates of sedimentation. One- and two-box modeling with 7Be and 210Pbexcess was used to determine soil and sediment residence times. Residence time of fine suspended particles is short and particles can travel the length of the river during a single storm, probably due to the short duration, high-intensity rainfalls which produce rapidly moving, steep flood waves. The readily detected peak of 137Cs activity in Cropp terrace and Hokitika gorge soils yielded sedimentation rates of 0.06-0.12 cm yr-1. At the Cropp terrace, inventory models of 210Pbexcess yield soil accumulation rates significantly less than those determined using the 137Cs activity peak. We attribute the differences to overestimation of 210Pbexcess in surface soils and to contrasting fallout fluxes, geochemical behavior and radionuclide contents of sedimenting materials. Total inventories of 210Pbexcess in soils greatly exceed the expected direct atmospheric deposition, suggesting that lateral transport of this nuclide occurs within the watershed. At the Hokitika gorge, all nuclides studied yielded similar sedimentation rates

  11. Global risk of radioactive fallout after major nuclear reactor accidents

    International Nuclear Information System (INIS)

    Lelieveld, J.; Kunkel, D.; Lawrence, M.G.

    2012-01-01

    Major reactor accidents of nuclear power plants are rare, yet the consequences are catastrophic. But what is meant by ''rare''? And what can be learned from the Chernobyl and Fukushima incidents? Here we assess the cumulative, global risk of exposure to radioactivity due to atmospheric dispersion of gases and particles following severe nuclear accidents (the most severe ones on the International Nuclear Event Scale, INES 7), using particulate "1"3"7Cs and gaseous "1"3"1I as proxies for the fallout. Our results indicate that previously the occurrence of INES 7 major accidents and the risks of radioactive contamination have been underestimated. Using a global model of the atmosphere we compute that on average, in the event of a major reactor accident of any nuclear power plant worldwide, more than 90% of emitted "1"3"7Cs would be transported beyond 50 km and about 50% beyond 1000 km distance before being deposited. This corroborates that such accidents have large-scale and trans-boundary impacts. Although the emission strengths and atmospheric removal processes of "1"3"7Cs and "1"3"1I are quite different, the radioactive contamination patterns over land and the human exposure due to deposition are computed to be similar. High human exposure risks occur around reactors in densely populated regions, notably in West Europe and South Asia, where a major reactor accident can subject around 30 million people to radioactive contamination. The recent decision by Germany to phase out its nuclear reactors will reduce the national risk, though a large risk will still remain from the reactors in neighbouring countries.

  12. Pathways of fallout radiocaesium via reindeer to man

    International Nuclear Information System (INIS)

    Gaare, E.; Staaland, H.

    1994-01-01

    The Chernobyl accident triggered a world wide monitoring and research activity. In the Nordic countries a renewed interest was taken in the lichen reindeer food chain. A wealth of data has been put on record, data that confirm experience from nuclear weapons tests. Like other animals reindeer are exposed to radioactive fallout through their food, and because they alone utilise lichens as forage, a high level of radiocaesium is found in their muscle. The lichen intake of reindeer varies from 70-80% of the diet in winter to 10-20% in summer. This factor, coupled with the short biological half-life of caesium in the reindeer body (10-20 days), leads to a strong seasonal variation: a late winter high that in the first years is about five times the late summer low of radiocaesium in the meat. The effective ecological halflives of reindeer food lichens are 5-7 years for species growing on ridgetops. Species from more sheltered habitats show longer halflives, 6-11 years. This is partly due to local resuspension. Predictions based upon experience so far show that it will take about 20 years before radiocaesium burdens are the same as those prior to the accident. Estimates indicate that the effective half-life of radiocaesium in the meat of grazing reindeer is 3-4 years for the post-Chernobyl period. This has justified early slaughter in the domestic reindeer industry and when hunting wild reindeer. Countermeasures based on fodder additives were tested successfully for domestic animals, both bentonite and ammonium iron(III)hexacyanoferrate may be given in several different ways prior to slaughter, in order to reduce the radiocaesium burden to below the critical level in the meat. We suggest that more research is needed on ecosystem recycling of 137 Cs as well as other resuspension in wilderness areas. The developing of countermeasures should also be continued, and a monitoring of fixed plots should be undertaken in major reindeer ranges. (orig.)

  13. October 2005 Debris Flows at Panabaj, Guatemala:Hazard Assessment

    Science.gov (United States)

    Sheridan, M. F.; Connor, C.; Connor, L.; Stinton, A.; Galacia, O. R.; Barrios, G.

    2007-05-01

    In October, 2005, tropical storm Stan caused heavy precipitation throughout much of Guatemala. In the community of Panabaj, Santiago Atitlán, a landslide of pyroclastic material originating high on the slopes of Tolimán volcano buried much of the community, leaving approximately 400 people dead. Current estimates by the Coordinadora Nacional para la Reducción de Desastres (CONRED) suggest that at least 2,600 people from the community of Panabaj, Santiago Atitlán have been displaced by the debris flows. Because the temporary housing for people displaced by the debris flows is located in an area that is geologically and morphologically similar to the area inundated by flows in October, 2005, this area may be potentially inundated by debris flows as well. In addition to the thousands of people living in temporary shelters, many hundreds of people are currently reoccupying land adjacent to or on the October, 2005 debris flows. Thus a large fraction of the surviving Panabaj community appears to remain at risk from future debris flows. We used differential GPS (Global Positioning System) to outline the boundaries of the debris flows, to estimate variation in flow thicknesses, and to determine their volumes. Mass movement on Tolimán volcano resulted in the generation of a moderate size debris flow (360,000 m3 of sediment plus water) that descended the volcano rapidly, bifurcated into two stream valleys high on the flanks of the volcano, and continued to descend both channels until these flows reached the alluvial fan near the shores of Lago de Atitlán. After bifurcating into two flows high on the flanks of the volcano, about 65% of the flow (by volume) descended the western channel, forming the Western flow. Approximately one kilometer above the alluvial fan, this channel descends steep topography, with a slope of 11.5°. This average slope gradually decreases down the channel, reaching only 5.3° just above the alluvial fan. In contrast, average slopes on the

  14. Debris Examination Using Ballistic and Radar Integrated Software

    Science.gov (United States)

    Griffith, Anthony; Schottel, Matthew; Lee, David; Scully, Robert; Hamilton, Joseph; Kent, Brian; Thomas, Christopher; Benson, Jonathan; Branch, Eric; Hardman, Paul; hide

    2012-01-01

    The Debris Examination Using Ballistic and Radar Integrated Software (DEBRIS) program was developed to provide rapid and accurate analysis of debris observed by the NASA Debris Radar (NDR). This software provides a greatly improved analysis capacity over earlier manual processes, allowing for up to four times as much data to be analyzed by one-quarter of the personnel required by earlier methods. There are two applications that comprise the DEBRIS system: the Automated Radar Debris Examination Tool (ARDENT) and the primary DEBRIS tool.

  15. Structural debris experiments at operation MILL RACE

    International Nuclear Information System (INIS)

    Rempel, J.R.; Beck, J.E.; McKee, R.G.

    1983-01-01

    Structural debris patterns as determined by the mechanisms of building collapse under airblast loading have been studied experimentally at MILL RACE, White Sands, NM. Three near full-size buildings were instrumented to observe deflections, accelerations and air pressures and exposed to two different regimes of incident blast pressure produced by HE simulating 1 kt, viz., 10 and 3 psi; after the shot enough wall debris was located and identified to provide estimates of debris movement. Two of the test buildings were unreinforced, load-bearing masonry, one located at each of the two incident overpressures. The third building was made of reinforced concrete panels and was exposed to approximately 25 psi. Preliminary estimates of the effect of arching on debris energy and distribution are presented

  16. New solutions for the space debris problem

    CERN Document Server

    Pelton, Joseph N

    2015-01-01

    Addressing a pressing issue in space policy, Pelton explores the new forms of technology that are being developed to actively remove the defunct space objects from orbit and analyzes their implications in the existing regime of international space law and public international law. This authoritative review covers the due diligence guidelines that nations are using to minimize the generation of new debris, mandates to de-orbit satellites at end of life, and innovative endeavours to remove non-functional satellites, upper stage rockets and other large debris from orbit under new institutional, financial and regulatory guidelines.  Commercial space services currently exceed 100 billion USD business per annum, but the alarming proliferation in the population of orbital debris in low, medium and geosynchronous satellite orbits poses a serious threat to all kinds of space assets and applications. There is a graver concern that the existing space debris will begin to collide in a cascading manner, generating furth...

  17. TMI defueling project fuel debris removal system

    International Nuclear Information System (INIS)

    Burdge, B.

    1992-01-01

    The three mile Island Unit 2 (TMI-2) pressurized water reactor loss-of-coolant accident on March 28, 1979, presented the nuclear community with many challenging remediation problems; most importantly, the removal of the fission products within the reactor containment vessel. To meet this removal problem, an air-lift system (ALS) can be used to employ compressed air to produce the motive force for transporting debris. Debris is separated from the transport stream by gravity separation. The entire method does not rely on any moving parts. Full-scale testing of the ALS at the Idaho National Engineering Laboratory (INEL) has demonstrated the capability of transporting fuel debris from beneath the LCSA into a standard fuel debris bucket at a minimum rate of 230 kg/min

  18. Comparison of an Inductance In-Line Oil Debris Sensor and Magnetic Plug Oil Debris Sensor

    Science.gov (United States)

    Dempsey, Paula J.; Tuck, Roger; Showalter, Stephen

    2012-01-01

    The objective of this research was to compare the performance of an inductance in-line oil debris sensor and magnetic plug oil debris sensor when detecting transmission component health in the same system under the same operating conditions. Both sensors were installed in series in the NASA Glenn Spiral Bevel Gear Fatigue Rig during tests performed on 5 gear sets (pinion/gear) when different levels of damage occurred on the gear teeth. Results of this analysis found both the inductance in-line oil debris sensor and magnetic plug oil debris sensor have benefits and limitations when detecting gearbox component damage.

  19. Marine debris: global and regional impacts

    OpenAIRE

    Torres N,Daniel; Berguño B,Jorge

    2011-01-01

    A synthesis on the Marine Debris problem is given upon de basis of the general knowledge on the matter as well as that obtained at Cape Shirreff, Livingston Island, South Shetland, Antarctica. It is suggested to improve the database on marine debris through permanent scientific research as well as with monitoring activities. It is necessary to coordinate key groups to apply strategies to identify types, sources, amount, interactions and socio-economic aspects of this global and regional probl...

  20. Postdetonation nuclear debris for attribution.

    Science.gov (United States)

    Fahey, A J; Zeissler, C J; Newbury, D E; Davis, J; Lindstrom, R M

    2010-11-23

    On the morning of July 16, 1945, the first atomic bomb was exploded in New Mexico on the White Sands Proving Ground. The device was a plutonium implosion device similar to the device that destroyed Nagasaki, Japan, on August 9 of that same year. Recently, with the enactment of US public law 111-140, the "Nuclear Forensics and Attribution Act," scientists in the government and academia have been able, in earnest, to consider what type of forensic-style information may be obtained after a nuclear detonation. To conduct a robust attribution process for an exploded device placed by a nonstate actor, forensic analysis must yield information about not only the nuclear material in the device but about other materials that went into its construction. We have performed an investigation of glassed ground debris from the first nuclear test showing correlations among multiple analytical techniques. Surprisingly, there is strong evidence, obtainable only through microanalysis, that secondary materials used in the device can be identified and positively associated with the nuclear material.

  1. Radioactive debris from operations Upshot and Knothole

    Energy Technology Data Exchange (ETDEWEB)

    1954-06-25

    Activities of the National Monitoring System are summarized for the period March 1 to June 15, 1953, during which eleven nuclear devices were fired at the Nevada Proving Grounds during Operation Upshot-Knothole. The program employed a world-wide network of 125 sampling locations. Each station collected samples of atmospheric dusts for radiometric analysis. A comparison is made of air concentrations and fall-out activities. Data are tabulated.

  2. Transport of fallout and reactor radionuclides in the drainage basin of the Hudson River estuary

    International Nuclear Information System (INIS)

    Simpson, H.J.; Linsalata, P.; Olsen, C.R.; Cohen, N.; Trier, R.M.

    1987-01-01

    Fallout plutonium and radiocesium derived from both weapons testing and local reactor releases are found in the water column and sediments of the Hudson River in readily measurable amounts. The history of fallout delivery and dissolved phase runoff from the drainage basin of 80 Sr, 137 Cs, and /sup 239,240/Pu have been extensively documented since the mid-1950s. Sediment and water column concentrations of 134 Cs, 137 Cs, and /sup 239,240/Pu in the Hudson have also been documented since the mid-1960's and are summarized. Since the peak fallout years, substantial portions of the fallout radionuclides in the drainage basin have become unavailable to normal weathering processes as reflected by a measured decrease in the fallout nuclide transport to the waters of the tidal Hudson. Budget calculations indicate that plutonium may be transported into the estuary from the coastal ocean, and that desorption of radiocesium from particles has allowed a substantial fraction of radiocesium to be exported from the Hudson to marine waters. 29 references, 6 figures, 8 tables

  3. Has fallout from the Chernobyl accident caused childhood leukaemia in Europe? An update on epidemiologic evidence

    International Nuclear Information System (INIS)

    Hoffmann, W.

    2001-01-01

    Background: According to radiation risk estimates uniformly adopted by various official organizations, exposure to Chernobyl fallout is unlikely to have caused any measurable health risk in central Europe. Methods and Results: A reevaluation of ECLIS (European Childhood Leukaemia and Lymphoma Incidence Study), a large IARC-coordinated project revealed a slightly higher leukaemia incidence in the most contaminated European regions, and an increasing trend with estimated cumulative excess radiation dose. The excess corresponds to 20 cases of childhood leukaemia in the study area until 1991. Recent evidence from Greece and Germany indicate significantly higher risks in the cohort of children in utero at the time of the initial fallout. In Greece, a positive trend was observed over three regions of increasing average fallout contamination (p=0.005). Conclusion: Chernobyl fallout could well have caused a small, but significant excess of childhood leukaemia cases in Europe. The etiologic mechanism might include an induction of chromosome aberrations in early pregnancy. Increased risks in the birth cohort exposed in utero correspond to 11 excess cases in Greece and another 11.4 excess cases in Germany alone. Exposure misclassification and underascertainment of incident cases render post-Chernobyl risk estimates probably too low. If indeed Chernobyl fallout has caused childhood leukaemia cases in Europe, we would also expect an increased incidence for other childhood cancers and excess malignancies in adults as well as non-malignant diseases of all ages. Neither of these endpoints have as yet been systematically studied. (orig.)

  4. Fragments and debris generation using a high power pulsed electron beam

    International Nuclear Information System (INIS)

    Cassany, Bruno; Courchinoux, Roger; Bertron, Isabelle; Malaise, Frederic; Hebert, David

    2002-01-01

    The high power Laser Megajoule (LMJ) will be constructed at CEA/DAM/CESTA near Bordeaux, in the south west part of France. Among the problems encountered in the LMJ experimental chamber, there is the impact of the debris produced after a laser shot on the silica optical windows. The production of debris as well as the behavior of optical materials under their influence can be simulated and studied with a pulsed electron beam. We present in this paper the first experimental results obtained by this original technique

  5. Global analysis of anthropogenic debris ingestion by sea turtles.

    Science.gov (United States)

    Schuyler, Qamar; Hardesty, Britta Denise; Wilcox, Chris; Townsend, Kathy

    2014-02-01

    Ingestion of marine debris can have lethal and sublethal effects on sea turtles and other wildlife. Although researchers have reported on ingestion of anthropogenic debris by marine turtles and implied incidences of debris ingestion have increased over time, there has not been a global synthesis of the phenomenon since 1985. Thus, we analyzed 37 studies published from 1985 to 2012 that report on data collected from before 1900 through 2011. Specifically, we investigated whether ingestion prevalence has changed over time, what types of debris are most commonly ingested, the geographic distribution of debris ingestion by marine turtles relative to global debris distribution, and which species and life-history stages are most likely to ingest debris. The probability of green (Chelonia mydas) and leatherback turtles (Dermochelys coriacea) ingesting debris increased significantly over time, and plastic was the most commonly ingested debris. Turtles in nearly all regions studied ingest debris, but the probability of ingestion was not related to modeled debris densities. Furthermore, smaller, oceanic-stage turtles were more likely to ingest debris than coastal foragers, whereas carnivorous species were less likely to ingest debris than herbivores or gelatinovores. Our results indicate oceanic leatherback turtles and green turtles are at the greatest risk of both lethal and sublethal effects from ingested marine debris. To reduce this risk, anthropogenic debris must be managed at a global level. © 2013 The Authors. Conservation Biology published by Wiley Periodicals, Inc., on behalf of the Society for Conservation Biology.

  6. Erosion and sediment deposition evaluation on a slope under pasture in Jandaia-GO using the '137Cs fallout' technique

    International Nuclear Information System (INIS)

    Arthur, Robson C.J.; Bacchi, Osny O.S.; Reichardt, Klaus; Oliveira, Carloeme Alves de; Correchel, Vladia

    2009-01-01

    Water erosion is one of the main forms of soil degradation and among the diverse factors that affect it, two of great importance are the soil cover and slope. Estimates of sediment distribution rates associated to the different uses and soil management practices are scarce and the employed methods in these determinations are in general costly and time consuming. Rates of sediment redistribution evaluated by means of the 137 Cs technique are based on the comparison of inventories of individual points of a given position and an inventory of reference, whose value represents the amount of 137 Cs of 'fallout' origin that was added to the local site. This allows evaluating situations of losses and accumulations of sediments by the erosive process. The objective of the present work was to analyze the sediment production in a pasture area and to measure the efficiency of riparian forests in trapping the erosion sediments coming from pasture, through the ' 137 Cs fallout' redistribution analysis. The study was carried out in Jandaia/GO, Brazil, in two dowslope transects located in a pasture area. Samples were taken from seven points of two 140 m long transects, as well as from three soil profiles of a 15 m transect in the downstream riparian forests of each transect. Soil profiles were sampled in three layers of 20 cm (0-20, 20-40 and 40-60). The soil samples were air dried, sieved and then analyzed for 137 Cs activity by a gamma ray detector (GEM-20180P, EG and ORTEC) coupled to a multichannel analyzer at CENA/USP. The results indicate variations of 137 Cs activity in soil profiles and high erosion rates to the riparian forest to the pasture areas of the two transects, showing sediment movement from the pasture area to the riparian forest, which suggests that the current width of the forest is not wide enough to trap the sediments produced upslope in the pasture area. (author)

  7. A globally complete map of supraglacial debris cover and a new toolkit for debris cover research

    Science.gov (United States)

    Herreid, Sam; Pellicciotti, Francesca

    2017-04-01

    A growing canon of literature is focused on resolving the processes and implications of debris cover on glaciers. However, this work is often confined to a handful of glaciers that were likely selected based on criteria optimizing their suitability to test a specific hypothesis or logistical ease. The role of debris cover in a glacier system is likely to not go overlooked in forthcoming research, yet the magnitude of this role at a global scale has not yet been fully described. Here, we present a map of debris cover for all glacierized regions on Earth including the Greenland Ice Sheet using 30 m Landsat data. This dataset will begin to open a wider context to the high quality, localized findings from the debris-covered glacier research community and help inform large-scale modeling efforts. A global map of debris cover also facilitates analysis attempting to isolate first order geomorphological and climate controls of supraglacial debris production. Furthering the objective of expanding the inclusion of debris cover in forthcoming research, we also present an under development suite of open-source, Python based tools. Requiring minimal and often freely available input data, we have automated the mapping of: i) debris cover, ii) ice cliffs, iii) debris cover evolution over the Landsat era and iv) glacier flow instabilities from altered debris structures. At the present time, debris extent is the only globally complete quantity but with the expanding repository of high quality global datasets and further tool development minimizing manual tasks and computational cost, we foresee all of these tools being applied globally in the near future.

  8. Triggering conditions and depositional characteristics of a disastrous debris flow event in Zhouqu city, Gansu Province, northwestern China

    Directory of Open Access Journals (Sweden)

    C. Tang

    2011-11-01

    Full Text Available On 7 August 2010, catastrophic debris flows were triggered by a rainstorm in the catchments of the Sanyanyu and Luojiayu torrents, Zhouqu County, Gansu Province northwestern China. These two debris flows originated shortly after a rainstorm with an intensity of 77.3 mm h−1 and transported a total volume of about 2.2 million m3, which was deposited on an existing debris fan and into a river. This catastrophic event killed 1765 people living on this densely urbanised fan. The poorly sorted sediment contains boulders up to 3–4 m in diameter. In this study, the geomorphological features of both debris flow catchment areas are analyzed based on the interpretation of high-resolution remote sensing imagery combined with field investigation. The characteristics of the triggering rainfall and the initiation of the debris flow occurrence are discussed. Using empirical equations, the peak velocities and discharges of the debris flows were estimated to be around 9.7 m s−1 and 1358 m3 s−1 for the Sanyanyu torrent and 11 m s−1 and 572 m3 s−1 for the Luojiayu torrent. The results of this study contribute to a better understanding of the conditions leading to catastrophic debris flow events.

  9. Direct tropospheric transport of debris from nuclear weapon detonations at the Semipalatinsk test site to Western Europe

    Energy Technology Data Exchange (ETDEWEB)

    Wendel, Cato C.; Oughton, Deborah H.; Lind, Ole Christian; Skipperud, Lindis; Salbu, Brit [CERAD CoE, Department of Environmental Sciences, Norwegian University of Life Sciences, P.O. Box 5003, N-1432 Aas (Norway); Fifield, L. Keith; Tims, Stephen G. [Department of Nuclear Physics, Australian National University, Canberra, ACT0200 (Australia); Bartnicki, Jerzy [Norwegian Meteorological institute (met.no), Oslo (Norway); Hoeibraaten, Steinar [Norwegian Defence Research Establishment (FFI), Kjeller (Norway)

    2014-07-01

    During 7.11.1962 through 13.11.1962 a wave of highly elevated gross beta activities were registered at surveillance air filter stations situated in different regions of Norway. A selection of air filters collected daily during this time period, was screened for radioactive particles using digital autoradiography and analysed with respect to the concentrations and atom ratios of plutonium (Pu) and uranium (U) using accelerator mass spectrometry (AMS). Elevated concentrations of {sup 236}U (1.4-20.1 nBq m{sup -3}) and {sup 239+240}Pu (5.6-782 μBq m{sup -3}) were found to be in good correlation with the observed gross beta activities (R{sup 2}>0.9), indicating the presence of fresh fallout from nuclear weapon detonations. The digital autoradiography images demonstrated the presence of radioactive particles in the filters. Low {sup 240}Pu/{sup 239}Pu (0.0517-0.083), {sup 241}Pu/{sup 239}Pu (0.00025-0.00062) and {sup 236}U/{sup 239}Pu (0.0188-0.046) atom ratios, characteristic of close-in and tropospheric fallout, were observed in filters collected during this incidence. Atmospheric transport modelling (NOAA HYSPLIT-4) using real-time meteorological data confirmed that long range transport to Norway of radioactive debris, including particles, from detonations 7 - 12 days earlier at the Semipalatinsk test site, Kazakhstan during this period was plausible. The present work shows that direct tropospheric transport of fallout from atmospheric nuclear detonations periodically may have had much larger influence than previously anticipated on radionuclide air concentrations and deposition at locations far from the test site. (authors)

  10. Carbon Stocks of Fine Woody Debris in Coppice Oak Forests at Different Development Stages

    Directory of Open Access Journals (Sweden)

    Ender Makineci

    2017-06-01

    Full Text Available Dead woody debris is a significant component of the carbon cycle in forest ecosystems. This study was conducted in coppice-originated oak forests to determine carbon stocks of dead woody debris in addition to carbon stocks of different ecosystem compartments from the same area and forests which were formerly elucidated. Weight and carbon stocks of woody debris were determined with recent samplings and compared among development stages (diameter at breast height (DBH, D1.3m, namely small-diameter forests (SDF = 0–8 cm, medium diameter forests (MDF = 8–20 cm, and large-diameter forests (LDF = 20–36 cm. Total woody debris was collected in samplings; as bilateral diameters of all woody debris parts were less than 10 cm, all woody parts were in the “fine woody debris (FWD” class. The carbon concentrations of FWD were about 48% for all stages. Mass (0.78–4.92 Mg·ha−1 and carbon stocks (0.38–2.39 Mg·ha−1 of FWD were significantly (p > 0.05 different among development stages. FWD carbon stocks were observed to have significant correlation with D1.3m, age, basal area, and carbon stocks of aboveground biomass (Spearman rank correlation coefficients; 0.757, 0.735, 0.709, and 0.694, respectively. The most important effects on carbon budgets of fine woody debris were determined to be coppice management and intensive utilization. Also, national forestry management, treatments of traditional former coppice, and conversion to high forest were emphasized as having substantial effects.

  11. The radioactive fall-out harm of nuclear burst to crops and its protection

    International Nuclear Information System (INIS)

    Zhao Wenhu; Xu Xinyu; Zhu Yongyi; Qiu Tongcai

    1990-10-01

    The radioactive contamination in the ground burst center is severe and the contaminated area is often large, as well as the effect of radioactive contamination is long. With different kinds of crops, the effects of external contamination caused by the fall-out are different. The contamination can easily be reduced by wind or rain. On the leaf surface it can be washed off and reduced to 10%. A small amount of fission product can be absorbed through plant roots. It is mainly distributed in leaves and stems. The radioactive contamination of fall-out would damage the crops and reduce the production. After an atmospheric test, the fall-out of 90 Sr and 137 Cs plays an important role in the biological effects. The absorption and distribution of radioactive contaminants in crops, their chemical states in soil and the measures to reduce the absorbed radioactivity are respectively studied

  12. 137Cs in soil and fallout around Zagreb (Croatia) at the time of the Fukushima accident.

    Science.gov (United States)

    Šoštarić, Marko; Petrinec, Branko; Babić, Dinko

    2013-12-01

    This paper addresses the noticeable increase of 137Cs activity concentrations in soil and fallout in the area surrounding Zagreb (Croatia) that occurred at the time of the 2011 Fukushima accident. This topic is important for public health as 137Cs is highly toxic due to its long half-life of radioactive decay and chemical similarity to potassium. 137Cs concentrations in fallout were much greater than in soil, but remained present longer in the latter. While being detectable in our measurements, 137Cs did not spread through the food chain in amounts exceeding the maximum allowed level of radioactive food contamination. However, more thorough and consistent measurements need to be done in order to establish the precise activity trends of 137Cs in Zagreb soil and fallout.

  13. Identification, testing, and analysis of a meteorite debris from jhelum, pakistan

    International Nuclear Information System (INIS)

    Kayani, S.

    2012-01-01

    In this research paper, X-ray diffraction (XRD) and X-ray fluorescence (XRF) spectrometry have been used to determine the mineralogical and elemental composition of a stone sample recovered from a location near village Lehri in district Jhelurn, Pakistan. The test data is compared with previous findings (as reported in literature and included in references) to identify this sample stone as part of a prehistoric meteorite ablation debris. Carbon content of a specimen of the meteorite debris has also been determined through combustion analysis. This carbon abundance has been compared with carbon wt% value of a certain type of meteorites to establ ish the origin and nature of the parent body of this particular meteorite debris. (author)

  14. Debris filtering effectiveness and pressure drop tests of debris resistance-bottom end piece

    International Nuclear Information System (INIS)

    Chung, Moon Ki; Song, Chul Hwa; Chung, Heung June; Won, Soon Yeun; Cho, Young Ro; Kim, Bok Deuk

    1992-03-01

    In this final report, described are the test conditions and test procedures for the debris filtering effectiveness and pressure drop tests for developing the Debris Resistance-Bottom End Piece (DR-BEP). And the test results are tabulated for later evaluation. (Author)

  15. Loopy, Floppy and Fragmented: Debris Characteristics Matter

    Science.gov (United States)

    Parrish, J.; Burgess, H. K.

    2016-02-01

    Marine debris is a world-wide problem threatening the health and safety of marine organisms, ecosystems, and humans. Recent and ongoing research shows that risk of harm is not associated with identity, but rather with a set of specific character states, where the character state space intersection is defined by the organism of interest. For example, intersections of material, color, rigidity and size predict the likelihood of an object being ingested: plastic, clear-white, floppy objects risks to sea turtles whereas yellow-red, rigid objects risks to albatrosses. A character state space approach allows prioritization of prevention and removal of marine debris informed by risk assessments for species of interest by comparing species ranges with spatio-temporal hotspots of all debris with characteristics known to be associated with increased risk of harm, regardless of identity. With this in mind, the Coastal Observation and Seabird Survey Team (COASST) developed and tested a 20 character data collection approach to quantifying the diversity and abundance of marine debris found on beaches. Development resulted in meta-analysis of the literature and expert opinion eliciting harmful character state space. Testing included data collection on inter-rater reliability and accuracy, where the latter included 75 participants quantifying marine debris characteristics on monthly surveys of 30 beaches along the Washington and Oregon coastlines over the past year. Pilot work indicates that characters must be simply and operationally defined, states must be listed, and examples must be provided for color states. Complex characters (e.g., windage, shape) are not replicable across multiple data collectors. Although data collection takes longer than other marine debris surveys for a given amount of debris and area surveyed, volunteer rapidity and accuracy improved within 3-5 surveys. Initial feedback indicated that volunteers were willing to continue collecting data as long as they

  16. Cosmogenic radionuclide 7Be in atmospheric fallouts, weather factors and solar activity

    International Nuclear Information System (INIS)

    Kungurov, F.R.

    2011-11-01

    Key words: 7 Be activity, atmospheric fallouts, solar activity, gamma spectroscopy. Subjects of research: cosmogenic radionuclide 7 Be in atmospheric fallouts and surrounding objects of environment, its migrational distribution connected to solar activity and weather meteorologic parameters of the region studied. Purpose of work: Defining correlation between atmospheric humidity and solar activity with concentration and distribution of cosmogenic radionuclide 7 Be. Methods of research: gamma-spectrometry method of activity measurements. The results obtained and their novelty: Cycle of research works on definition of concentration and migrational distribution of CRN 7 Be in Samarkand region during 2002-2005 was carried out for the first time. Volumetric activity of 7 Be in squat air layer of Samarkand was determined. Average density of 7 Be fallouts for the four years of studies was determined. Qualitative correlation bet ween 7 Be fallouts density variations and solar activity, expressed through Wolf number has been found. Qualitative correlation between 7 Be fallouts density variations and amount of precipitations has been found. Regularity in 7 Be concentration decrease towards north latitudes has been detected. Practical value: Developed scintillation method of 7 Be activity detection in atmospheric fallouts was used in works performed in the framework of republican grants 2F-No 1.2.3, CNT RUz PFNI 2F-No 2.1.39 and ITD-7-024. Methodology was used for the estimation of the velocity of erosion processes in the soils of different regions of Uzbekistan. Methodology is used in the works on 7 Be radioactivity measurements. Degree of embed and economic effectivity: Gained results replenish database on 7 Be isotope distribution on Earth regions and its role in formation of some processes, connected with meteorology, agronomy and radioecology of Samarkand region. Field of application: meteorology, agronomy and radioecology. (author)

  17. Fallout deposition in the Marshall Islands from Bikini and Enewetak nuclear weapons tests.

    Science.gov (United States)

    Beck, Harold L; Bouville, André; Moroz, Brian E; Simon, Steven L

    2010-08-01

    Deposition densities (Bq m(-2)) of all important dose-contributing radionuclides occurring in nuclear weapons testing fallout from tests conducted at Bikini and Enewetak Atolls (1946-1958) have been estimated on a test-specific basis for 32 atolls and separate reef islands of the Marshall Islands. A complete review of various historical and contemporary data, as well as meteorological analysis, was used to make judgments regarding which tests deposited fallout in the Marshall Islands and to estimate fallout deposition density. Our analysis suggested that only 20 of the 66 nuclear tests conducted in or near the Marshall Islands resulted in substantial fallout deposition on any of the 23 inhabited atolls. This analysis was confirmed by the fact that the sum of our estimates of 137Cs deposition from these 20 tests at each atoll is in good agreement with the total 137Cs deposited as estimated from contemporary soil sample analyses. The monitoring data and meteorological analyses were used to quantitatively estimate the deposition density of 63 activation and fission products for each nuclear test, plus the cumulative deposition of 239+240Pu at each atoll. Estimates of the degree of fractionation of fallout from each test at each atoll, as well as of the fallout transit times from the test sites to the atolls were used in this analysis. The estimates of radionuclide deposition density, fractionation, and transit times reported here are the most complete available anywhere and are suitable for estimations of both external and internal dose to representative persons as described in companion papers.

  18. Mixed debris treatment at the Idaho National Engineering Laboratory (INEL)

    International Nuclear Information System (INIS)

    Garcia, E.C.; Porter, C.L.; Wallace, M.T.

    1993-01-01

    August 18, 1992 the Environmental Protection Agency (EPA) published the final revised treatment standards for hazardous debris, including mixed debris. (1) Whereas previous standards had been concentration based, the revised standards are performance based. Debris must be treated prior to land disposal, using specific technologies from one or more of the following families of debris treatment technologies: Extraction, destruction, or immobilization. Seventeen specific technologies with generic application are discussed in the final rule. The existing capabilities and types of debris at the INEL were scrubbed against the debris rule to determine an overall treatment strategy. Seven types of debris were identified: combustible, porous, non-porous, inherently hazardous, HEPA filters, asbestos contaminated, and reactive metals contaminated debris. With the exception of debris contaminated with reactive metals treatment can be achieved utilizing existing facilities coupled with minor modifications

  19. Mixed debris treatment at the Idaho National Engineering Laboratory (INEL)

    International Nuclear Information System (INIS)

    Garcia, E.C.; Porter, C.L.; Wallace, M.T.

    1993-01-01

    August 18, 1992 the EPA published the final revised treatment standards for hazardous debris, including mixed debris. Whereas previous standards had been concentration based, the revised standards are performance based. Debris must be treated prior to land disposal, using specific technologies from one or more of the following families of debris treatment technologies: Extraction, destruction, or immobilization. Seventeen specific technologies with generic application are discussed in the final rule. The existing capabilities and types of debris at the INEL were evaluated against the debris rule to determine an overall treatment strategy for the INEL. Seven types of debris were identified: Combustible, porous, non-porous, inherently hazardous, HEPA filters, asbestos contaminated, and reactive metals contaminated debris. With the exception of debris contaminated with reactive metals treatment can be achieved utilizing existing facilities coupled with minor modifications

  20. Thermal-hydraulic and characteristic models for packed debris beds

    International Nuclear Information System (INIS)

    Mueller, G.E.; Sozer, A.

    1986-12-01

    APRIL is a mechanistic core-wide meltdown and debris relocation computer code for Boiling Water Reactor (BWR) severe accident analyses. The capabilities of the code continue to be increased by the improvement of existing models. This report contains information on theory and models for degraded core packed debris beds. The models, when incorporated into APRIL, will provide new and improved capabilities in predicting BWR debris bed coolability characteristics. These models will allow for a more mechanistic treatment in calculating temperatures in the fluid and solid phases in the debris bed, in determining debris bed dryout, debris bed quenching from either top-flooding or bottom-flooding, single and two-phase pressure drops across the debris bed, debris bed porosity, and in finding the minimum fluidization mass velocity. The inclusion of these models in a debris bed computer module will permit a more accurate prediction of the coolability characteristics of the debris bed and therefore reduce some of the uncertainties in assessing the severe accident characteristics for BWR application. Some of the debris bed theoretical models have been used to develop a FORTRAN 77 subroutine module called DEBRIS. DEBRIS is a driver program that calls other subroutines to analyze the thermal characteristics of a packed debris bed. Fortran 77 listings of each subroutine are provided in the appendix

  1. LATE PLIOCENE-HOLOCENE DEBRIS FLOW DEPOSITS IN THE IONIAN SEA (EASTERN MEDITERRANEAN

    Directory of Open Access Journals (Sweden)

    GIOVANNI ALOISI DE LARDEREL

    1997-11-01

    Full Text Available Widespread coring of the Eastern Mediterranean Basin has outlined the existence of a systematic relation between lithology of debris flow deposits and physiographic setting. Whilst the topographic highs are characterized by pelagic sedimentation, the basin floors are alternatively subject to pelagic sedimentation and re-sedimentation pro cesses. Amongst the latters, turbidity flows and debris flows are the most common transport mechanisms.In this paper we present the study of the debris flow pro cess in the Ionian Sea using visual description of cores, grain size, carbonate content and smear slide analysis carried out on gravity and piston cores recovered over the past 20 years. A distinction has been made between debris flow deposits originating from the continental margins (North Africa and Malta Escarpment and those emplaced in the small basins amidst the Calabrian and Mediterranean ridges "Cobblestone Topography". As a result of the difference in setting, the former debris flow deposits include a great variety of lithologies and ages whilst the latter involve the pelagic sediments forming the typical Eastern Mediterranean Plio-Quaternary succession. A detailed study of clast and matrix structures makes it possible to describe the flows in terms of existing classifications of sediment gravity flows and to assume a clast support mechanism. Finally, biostratigraphy coupled with the presence of widespread marker beds enabled us to estimate the age of emplacement of the deposits and to hypothesize a triggering mechanism for flow initiation. Three flows are strictly related to the pelagic turbidite named homogenite, triggered by the explosive eruption of the Santorini volcano (Minoan eruption and therefore have an estimated age of 3,500 BP. The other deposits have ages ranging from 9,000 BP to about 70,000 BP and were originated by debris flows triggered by events such as earthquakes and glacial low sea level stands.    

  2. Fallout cesium-137 and mineral-element distribution in food chains of granitic-outcrop ecosystems

    International Nuclear Information System (INIS)

    Crossley, D.A. Jr.; Duke, K.M.; Waide, J.B.

    1975-01-01

    Fallout 137 Cs movement is described for arthropod food chains on Panola and Arabia mountains, granite monadnocks in the Georgia Piedmont region. Food chains on mountain slopes had significant 137 Cs in herbivore and predator trophic levels. Food bases were identified from observation and from cesium to potassium ratios in vegetation and arthropods. Lichens are major accumulators of fallout 137 Cs but do not appear to be important food sources for arthropods. Cesium-137 concentrations decrease in the food chains; these decreases resemble those reported for other terrestrial arthropod chains. Aspects of 137 Cs movement and nutrient-element dynamics in granitic-outcrop ecosystems are discussed

  3. Organizational and social-psychological issues relevant to fallout-shelter evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Wernette, D.R.

    1983-01-01

    This paper presents the results of a preliminary review of the literature on organizational and social-psychological issues relevant to fallout-shelter evaluation. Fallout-shelter options are evaluated along two dimensions: shelter size, and extent of shelteree participation in the shelter construction. Four functional criteria are used in the evaluation: decision-making, member coordination, social control, and maintaining morale. Smaller shelters requiring shelteree participation in construction appear preferable as measured in most of these criteria. Additional factors mentioned include demographic characteristics of the shelter population, degree and type of ventilation system, and availability of medical equipment and personnel. 10 references.

  4. Estimated inventory of plutonium and uranium radionuclides for vegetation in aged fallout areas

    International Nuclear Information System (INIS)

    Romney, E.M.; Gilbert, R.O.; Wallace, A.; Kinnear, J.

    1976-02-01

    Data are presented on the contamination of vegetation by 239 Pu, 240 Pu, and other radionuclides in aged fallout areas on the Nevada Test Site (NTS) and the Tonopah Test Range (TTR). Comparisons of soil and vegetation inventory estimates indicate that the standing vegetation contributes an insignificant portion of the total amount of 239-240 Pu present in these aged fallout areas. The amounts of Pu available for vegetation-transport to animals grazing on-site would appear to be relatively small in comparison to the total amounts deposited upon soil. Findings indicate that most of the contaminant found on vegetation probably is attributable to resuspendable materials

  5. Results of ten years study of Chernobyl NPP release fallout properties and behaviour in soils

    International Nuclear Information System (INIS)

    Ivanov, Yu.; Kashparov, V.A.; Levchuk, S.; Protsak, V.; Zvaritch, S.; Khomutinin, Yu.; Oreshich, L.

    1997-01-01

    Radioactive contamination of territories of Ukrainian and Byelorussian Polesye as a result of ChNPP accidental release is characterized by high level of un-homogenity of fallout properties (physico-chemical properties, radionuclide composition etc.), density of the territory contamination by long-lived radionuclides. On the other hand, the soil-plant cover of contaminated territory is presented by large set of soils, characterized by contrast physico-chemical and water-physical properties. Peculiarities of the behavior of different radionuclides, represented initially by various components of radioactive fallout, in soils, as a first link of migration chains are considered

  6. Analysis of fresh fallout from Chinese tests by beta counting technique

    International Nuclear Information System (INIS)

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

    1979-01-01

    The paper describes beta counting techniques used in the analysis of fresh radioactive fallout samples from nuclear weapon tests. Fresh fallout samples have been collected by swiping the exposed portion of the engine covers of commercial aircrafts arriving at Bombay from New York after Chinese tests on September 26, 1976 and September 17, 1977. Activities of short-lived radionuclides such as Ag 111, Sr 89, Mo 99, U 237 and Np 239 were determined using these techniques. The results obtained from this analysis is discussed in brief in relation to the kind of fissile material, the extent of thermonuclear reaction in the weapon and the mode of detonation. (orig.) [de

  7. Ground depositions and air concentrations of Chernobyl fallout radionuclides at Munich-Neuherberg

    Energy Technology Data Exchange (ETDEWEB)

    Hoetzl, H.; Rosner, G.; Winkler, R.

    1987-01-01

    Southern Bavaria has received a comparatively high deposition of fallout radionuclides from the reactor accident at Chernobyl. As a result, in addition to the measurement of numerous gamma emitting nuclides and of strontium isotopes, the determination of several actinides, including isotopes of uranium, neptunium, plutonium and curium was possible. The observed radionuclide composition of the fallout and the time course of ground deposition and air concentration at the site of the Gesellschaft fuer Strahlen- und Umweltforschung (GSF) at Neuherberg, 10 km north of Munich, are reported and discussed.

  8. Ground depositions and air concentrations of Chernobyl fallout radionuclides at Munich-Neuherberg

    International Nuclear Information System (INIS)

    Hoetzl, H.; Rosner, G.; Winkler, R.

    1987-01-01

    Southern Bavaria has received a comparatively high deposition of fallout radionuclides from the reactor accident at Chernobyl. As a result, in addition to the measurement of numerous gamma emitting nuclides and of strontium isotopes, the determination of several actinides, including isotopes of uranium, neptunium, plutonium and curium was possible. The observed radionuclide composition of the fallout and the time course of ground deposition and air concentration at the site of the Gesellschaft fuer Strahlen- und Umweltforschung (GSF) at Neuherberg, 10 km north of Munich, are reported and discussed. (orig.)

  9. DELFIC: Department of Defense Fallout Prediction System. Volume II. User’s Manual

    Science.gov (United States)

    1979-12-31

    code, and it strives to include as much of the physics of fallout transport and activity calculation, without resorting to short cuts, as is...fission may be specified. Induced activity in soil material in the fallout and in 2 3BU may be accounted for. Physical and mathematical bases for...900o) *GTo 1.) GO TO 150 ATMR 140 ALT(13=-i003. ATAR 14± GO TO 20O ATNR ±42 15C WRITE(IRISE)ATMSU8 ATMR ±43 160 IGG=IGO+i ATMR 144 C ATMR 145 C CO THE

  10. The history of tritium fallout in southern Australia as inferred from rainfall and wine samples

    International Nuclear Information System (INIS)

    Allison, G.B.; Hughes, M.W.

    1977-01-01

    Rainfall and wine samples have been analysed for tritium in order to obtain a record of tritium fallout since 1950 for use in hydrologic studies in southern Australia. The tritium concentrations of rainfall have been estimated for years when no samples are available by using measured values of the tritium concentration of wine samples together with Roether's (1967) exchange model and a simple model for predicting the age of soil water used by vines. As expected, the tritium fallout pattern is similar to that obtained for Kaitoke in New Zealand and Pretoria in southern Africa. (Auth.)

  11. Original Researc Original Research

    African Journals Online (AJOL)

    RAGHAVENDRA

    Practices. Problems. Supervision. Primary School. *Corresponding Author: Asrat Dagnew. E-mail: asratboza@yahoo.com tructional support. The relevant and ... vision is one of indispensable system pment. Supervision is a system of that directly concerned on the aff members in a school or other. Original Research ...

  12. Original Research Original Research

    African Journals Online (AJOL)

    RAGHAVENDRA

    language in social interaction( Anto et al., 2012; Tessema et al., 2012). While such ..... 10 items on a five-point Likert scale originally developed by Benard et al. (2007). ..... self-confidence, and hold down their anxiety levels. In this study ...

  13. Debris disc constraints on planetesimal formation

    Science.gov (United States)

    Krivov, Alexander V.; Ide, Aljoscha; Löhne, Torsten; Johansen, Anders; Blum, Jürgen

    2018-02-01

    Two basic routes for planetesimal formation have been proposed over the last decades. One is a classical `slow-growth' scenario. Another one is particle concentration models, in which small pebbles are concentrated locally and then collapse gravitationally to form planetesimals. Both types of models make certain predictions for the size spectrum and internal structure of newly born planetesimals. We use these predictions as input to simulate collisional evolution of debris discs left after the gas dispersal. The debris disc emission as a function of a system's age computed in these simulations is compared with several Spitzer and Herschel debris disc surveys around A-type stars. We confirm that the observed brightness evolution for the majority of discs can be reproduced by classical models. Further, we find that it is equally consistent with the size distribution of planetesimals predicted by particle concentration models - provided the objects are loosely bound `pebble piles' as these models also predict. Regardless of the assumed planetesimal formation mechanism, explaining the brightest debris discs in the samples uncovers a `disc mass problem'. To reproduce such discs by collisional simulations, a total mass of planetesimals of up to ˜1000 Earth masses is required, which exceeds the total mass of solids available in the protoplanetary progenitors of debris discs. This may indicate that stirring was delayed in some of the bright discs, that giant impacts occurred recently in some of them, that some systems may be younger than previously thought or that non-collisional processes contribute significantly to the dust production.

  14. Cetaceans and Marine Debris: The Great Unknown

    Directory of Open Access Journals (Sweden)

    Mark Peter Simmonds

    2012-01-01

    Full Text Available Plastics and other marine debris have been found in the gastrointestinal tracts of cetaceans, including instances where large quantities of material have been found that are likely to cause impairment to digestive processes and other examples, where other morbidity and even death have resulted. In some instances, debris may have been ingested as a result of the stranding process and, in others, it may have been ingested when feeding. Those species that are suction or “ram” feeders may be most at risk. There is also evidence of entanglement of cetaceans in marine debris. However, it is usually difficult to distinguish entanglement in active fishing gear from that in lost or discarded gear. The overall significance of the threat from ingested plastics and other debris remains unclear for any population or species of cetaceans, although there are concerns for some taxa, including at the population level, and marine debris in the oceans continues to grow. Further research including the compilation of unpublished material and the investigation of important habitat areas is strongly recommended.

  15. Catastrophic debris flows transformed from landslides in volcanic terrains : mobility, hazard assessment and mitigation strategies

    Science.gov (United States)

    Scott, Kevin M.; Macias, Jose Luis; Naranjo, Jose Antonio; Rodriguez, Sergio; McGeehin, John P.

    2001-01-01

    Communities in lowlands near volcanoes are vulnerable to significant volcanic flow hazards in addition to those associated directly with eruptions. The largest such risk is from debris flows beginning as volcanic landslides, with the potential to travel over 100 kilometers. Stratovolcanic edifices commonly are hydrothermal aquifers composed of unstable, altered rock forming steep slopes at high altitudes, and the terrain surrounding them is commonly mantled by readily mobilized, weathered airfall and ashflow deposits. We propose that volcano hazard assessments integrate the potential for unanticipated debris flows with, at active volcanoes, the greater but more predictable potential of magmatically triggered flows. This proposal reinforces the already powerful arguments for minimizing populations in potential flow pathways below both active and selected inactive volcanoes. It also addresses the potential for volcano flank collapse to occur with instability early in a magmatic episode, as well as the 'false-alarm problem'-the difficulty in evacuating the potential paths of these large mobile flows. Debris flows that transform from volcanic landslides, characterized by cohesive (muddy) deposits, create risk comparable to that of their syneruptive counterparts of snow and ice-melt origin, which yield noncohesive (granular) deposits, because: (1) Volcano collapses and the failures of airfall- and ashflow-mantled slopes commonly yield highly mobile debris flows as well as debris avalanches with limited runout potential. Runout potential of debris flows may increase several fold as their volumes enlarge beyond volcanoes through bulking (entrainment) of sediment. Through this mechanism, the runouts of even relatively small collapses at Cascade Range volcanoes, in the range of 0.1 to 0.2 cubic kilometers, can extend to populated lowlands. (2) Collapse is caused by a variety of triggers: tectonic and volcanic earthquakes, gravitational failure, hydrovolcanism, and

  16. LightForce Photon-Pressure Collision Avoidance: Efficiency Assessment on an Entire Catalogue of Space Debris

    Science.gov (United States)

    Stupl, Jan Michael; Faber, Nicolas; Foster, Cyrus; Yang Yang, Fan; Levit, Creon

    2013-01-01

    The potential to perturb debris orbits using photon pressure from ground-based lasers has been confirmed by independent research teams. Two useful applications of this scheme are protecting space assets from impacts with debris and stabilizing the orbital debris environment, both relying on collision avoidance rather than de-orbiting debris. This paper presents the results of a new assessment method to analyze the efficiency of the concept for collision avoidance. Earlier research concluded that one ground based system consisting of a 10 kW class laser, directed by a 1.5 m telescope with adaptive optics, can prevent a significant fraction of debris-debris collisions in low Earth orbit. That research used in-track displacement to measure efficiency and restricted itself to an analysis of a limited number of objects. As orbit prediction error is dependent on debris object properties, a static displacement threshold should be complemented with another measure to assess the efficiency of the scheme. In this paper we present the results of an approach using probability of collision. Using a least-squares fitting method, we improve the quality of the original TLE catalogue in terms of state and co-state accuracy. We then calculate collision probabilities for all the objects in the catalogue. The conjunctions with the highest risk of collision are then engaged by a simulated network of laser ground stations. After those engagements, the perturbed orbits are used to re-assess the collision probability in a 20 minute window around the original conjunction. We then use different criteria to evaluate the utility of the laser-based collision avoidance scheme and assess the number of base-line ground stations needed to mitigate a significant number of high probability conjunctions. Finally, we also give an account how a laser ground station can be used for both orbit deflection and debris tracking.

  17. Late Miocene Debris-Avalanche Deposit At The Gutai Shield Volcano, NW Romania. Re- Evaluation Of Geological Mapping And Mineral Deposits

    Science.gov (United States)

    Seghedi, I.; Fülöp, A.

    2009-05-01

    The recent identification of debris avalanche deposits (DADs) originating from the southern edge of the Ignis peak (1306m, highest of the Gutai Mts.) has important implications for understanding its genesis in the geological context of the broader area, rich in hydrothermal intrusive-related base metal and gold-silver deposits closely connected to the Dragos Voda - Bogdan Voda strike-slip fault system. Pyroxene andesite lavas are exposed below the Ignis peak followed by hornblende and pyroxene andesites the only ones found in the DAD. The flank failure event has left an E-W-oriented horseshoe shaped scar with an estimated volume of material removed of at least 0.35 km3 and an estimated area covered by DADs of 4,345 km2 as a minimum. The deposit is a mega breccia with a variable amount of coarse matrix with jigsaw-fractured blocks, large boulders, and several southward-elongated hummocks up to 1.8 km distance from the scar. Between 720-850 m altitude the DADs contain megablocks of 5-12 m thick and up to 100 m long of layered fine-grained poorly consolidated pyroclastic materials of interlayered ash and lapillistone of fallout origin, and clay beds rich in vegetation remnants(known as the 'Chiuzbaia flora' of similar age as the surrounding lava flows, i.e. ca. 10-7 Ma) and diatoms. These megablocks found in various positions, suggest a lithological discontinuity likely representing the detachment surface of the gravity-driven instability phenomenon and the deep excavation of the volcano flank by the sector collapse event. The clayey material of these blocks acted probably as an efficient barrier to water infiltration and helped destabilization of the overlying rock mass. Since no explosive products have been observed to follow the DAD, it is possible that the sliding was triggered by pressure release of hydrothermal system along an E-W fault parallel to the Dragos Voda-Bogdan Voda fault system, with related high-grade ore deposits. This suggests the possible presence

  18. Orbital debris: a technical assessment

    National Research Council Canada - National Science Library

    National Research Council Staff; Commission on Engineering and Technical Systems; Division on Engineering and Physical Sciences; National Research Council; National Academy of Sciences

    ... Systems National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1995 i Copyrightoriginal retained, the be not from cannot book, paper original however, for version formatting, authoritative the typesetting-specific created from the as publication files other XML and from this of recomposed styles, version heading print the breaks...

  19. Widespread detection of a brominated flame retardant, hexabromocyclododecane, in expanded polystyrene marine debris and microplastics from South Korea and the Asia-Pacific coastal region

    International Nuclear Information System (INIS)

    Jang, Mi; Shim, Won Joon; Han, Gi Myung; Rani, Manviri; Song, Young Kyoung; Hong, Sang Hee

    2017-01-01

    The role of marine plastic debris and microplastics as a carrier of hazardous chemicals in the marine environment is an emerging issue. This study investigated expanded polystyrene (EPS, commonly known as styrofoam) debris, which is a common marine debris item worldwide, and its additive chemical, hexabromocyclododecane (HBCD). To obtain a better understanding of chemical dispersion via EPS pollution in the marine environment, intensive monitoring of HBCD levels in EPS debris and microplastics was conducted in South Korea, where EPS is the predominant marine debris originate mainly from fishing and aquaculture buoys. At the same time, EPS debris were collected from 12 other countries in the Asia-Pacific region, and HBCD concentrations were measured. HBCD was detected extensively in EPS buoy debris and EPS microplastics stranded along the Korean coasts, which might be related to the detection of a quantity of HBCD in non-flame-retardant EPS bead (raw material). The wide detection of the flame retardant in sea-floating buoys, and the recycling of high-HBCD-containing EPS waste inside large buoys highlight the need for proper guidelines for the production and use of EPS raw materials, and the recycling of EPS waste. HBCD was also abundantly detected in EPS debris collected from the Asia-Pacific coastal region, indicating that HBCD contamination via EPS debris is a common environmental issue worldwide. Suspected tsunami debris from Alaskan beaches indicated that EPS debris has the potential for long-range transport in the ocean, accompanying the movement of hazardous chemicals. The results of this study indicate that EPS debris can be a source of HBCD in marine environments and marine food web. - Highlights: • A brominated flame retardant, HBCD, was assessed in EPS debris and microplastics. • HBCD was widely detected in EPS debris from the Asia-Pacific coastal region. • Additive HBCD are dispersed via EPS pollution in marine environments. • EPS debris can be a

  20. Flow characteristics of counter-current flow in debris bed

    International Nuclear Information System (INIS)

    Abe, Yutaka; Adachi, Hiromichi

    2004-01-01

    In the course of a severe accident, a damaged core would form a debris bed consisting of once-molten and fragmented fuel elements. It is necessary to evaluate the dryout heat flux for the judgment of the coolability of the debris bed during the severe accident. The dryout phenomena in the debris bed is dominated by the counter-current flow limitation (CCFL) in the debris bed. In this study, air-water counter-current flow behavior in the debris bed is experimentally investigated with glass particles simulating the debris beds. In this experiment, falling water flow rate and axial pressure distributions were experimentally measured. As the results, it is clarified that falling water flow rate becomes larger with the debris bed height and the pressure gradient in the upper region of the debris bed is different from that in the lower region of the debris bed. These results indicate that the dominant region for CCFL in the debris bed is identified near the top of the debris bed. Analytical results with annular flow model indicates that interfacial shear stress in the upper region of the debris bed is larger than that in the lower region of the debris bed. (author)

  1. Tracing the sources of fine sediment in a nickel mining catchment using fallout and geogenic radionuclides (Thio River, New Caledonia)

    Science.gov (United States)

    Evrard, Olivier; Navratil, Oldrich; Lefèvre, Irène; Laceby, J. Patrick; Allenbach, Michel

    2016-04-01

    Soil erosion and subsequent sediment transfer in rivers are exacerbated in tropical regions exposed to heavy rainfall. In New Caledonia, an island located in the southwestern part of the Southern Pacific Ocean, a significant fraction of this sediment is likely originating from tributaries draining nickel mining sites that are known to increase the terrigenous inputs to the rivers and, potentially to UNESCO World Heritage listed coastal lagoons. However, downstream contributions from these tributaries remain to be quantified. A pilot sediment tracing study has therefore been conducted in the 400-km² Thio River catchment. Fallout and geogenic radionuclides have been measured in sediment deposits collected in potential sources, i.e. (i) tributaries draining mines, (ii) tributaries draining 'natural' areas affected by landslides, and (iii) the main stem of the Thio River. Thorium-228 and Caesium-137 provide the best discrimination between sediment originating from the two tributaries. A distribution modelling approach was used to quantify the relative sediment contributions from these tributaries to the Thio River main stem. Results demonstrate that tributaries draining mining sites supply the majority of sediment (67-84%) to the main river. In the future, the validity of these results obtained on sediment deposits collected in April and May 2015 should be verified over a longer time period by applying a similar approach to sediment cores collected in the Thio river deltaic plain. Once validated, this method will be applicable to other catchments draining mines in New Caledonia to design appropriate measures to limit sediment supply to the lagoon.

  2. Apparatus for controlling molten core debris

    International Nuclear Information System (INIS)

    Golden, M.P.; Tilbrook, R.W.; Heylmun, N.F.

    1972-01-01

    Disclosed is an apparatus for containing, cooling, diluting, dispersing and maintaining subcritical the molten core debris assumed to melt through the bottom of a nuclear reactor pressure vessel in the unlikely event of a core meltdown. The apparatus is basically a sacrificial bed system which includes an inverted conical funnel, a core debris receptacle including a spherical dome, a spherically layered bed of primarily magnesia bricks, a cooling system of zig-zag piping in graphite blocks about and below the bed and a cylindrical liner surrounding the graphite blocks including a steel shell surrounded by firebrick. Tantalum absorber rods are used in the receptacle and bed. 9 claims, 22 figures

  3. Electrometallurgical treatment of TMI-2 fuel debris

    International Nuclear Information System (INIS)

    Karell, E.J.; Gourishankar, K.V.; Johnson, G.K.

    1997-01-01

    Argonne National Laboratory (ANL) has developed an electrometallurgical treatment process suitable for conditioning DOE oxide spent fuel for long-term storage or disposal. The process consists of an initial oxide reduction step that converts the actinide oxides to a metallic form, followed by an electrochemical separation of uranium from the other fuel constituents. The final product of the process is a uniform set of stable waste forms suitable for long-term storage or disposal. The suitability of the process for treating core debris from the Three Mile Island-2 (TMI-2) reactor is being evaluated. This paper reviews the results of preliminary experimental work performed using simulated TMI-2 fuel debris

  4. A simple model to estimate deposition based on a statistical reassessment of global fallout data

    DEFF Research Database (Denmark)

    Palsson, S.E.; Howard, B.J.; Bergan, T.D.

    2013-01-01

    . A correlation was identified between fallout deposition and precipitation and an uneven distribution with latitude. In this study, the available data from 1954 to 1976 for 90Sr and 137Cs were reanalysed using analysis of covariance (ANCOVA) and logarithmically transformed values of the monthly deposition...

  5. Gamma ray spectra recorded from the fallout collected in May 1986

    International Nuclear Information System (INIS)

    Cristu, M.I.

    1987-07-01

    An analysis of the gamma ray spectra recorded from the fallout collective in Bucharest and Brasov in May, 1986 was carried out. Relative activities of the assigned radionuclides were computed and the duration of the 235 U fuel irradiation has been deduced. (author)

  6. Preliminary evaluation of crisis-relocation fallout-shelter options. Volume 2. Detailed analysis

    International Nuclear Information System (INIS)

    Santini, D.J.; Clinch, J.M.; Davis, F.H.; Hill, L.G.; Lynch, E.P.; Tanzman, E.A.; Wernette, D.R.

    1982-12-01

    This report presents a preliminary, detailed evaluation of various shelter options for use if the President orders crisis relocation of the US urban population because of strong expectation of a nuclear war. The availability of livable shelter space at 40 ft 2 per person (congregate-care space) by state is evaluated. Options are evaluated for construction of fallout shelters allowing 10 ft 2 per person - such shelters are designed to provide 100% survival at projected levels of radioactive fallout. The FEMA concept of upgrading existing buildings to act as fallout shelters can, in principle, provide adequate shelter throughout most of the US. Exceptions are noted and remedies proposed. In terms of upgrading existing buildings to fallout shelter status, great benefits are possible by turning away from a standard national approach and adopting a more site-specific approach. Existing FEMA research provides a solid foundation for successful crisis relocation planning, but the program can be refined by making suitable modifications in its locational, engineering, and institutionally specific elements

  7. Public health impact of fallout from British nuclear weapons tests in Australia, 1952-1957

    International Nuclear Information System (INIS)

    Wise, K.N.; Moroney, J.R.

    1992-05-01

    During the period 1952-1957, Britain conducted 12 full-scale nuclear weapons tests in Australia in five series, viz. Hurricane(1952), Totem(1953), Mosaic(1956), Buffalo(1956) and Antler(1957). Radioactive fallout from the tests reached many parts of Australia. This report reviews the pathways by which the radionuclides in the fallout could have irradiated the population. The methodology is presented for estimating the radiation doses and values are derived from the available data. The possible effect that the radiation exposure had on public health is assessed. Estimation of the radiation doses is approached in two parts: (a) the contributions from the Mosaic, Buffalo and Antler series which were monitored, and (b) the contributions from the Hurricane and Totem series for which there are few fallout data. In part (a), the activities of the radionuclides making up the measured fallout are established by calculation. Standard models are then used to derive the radiation doses for the population centres - from external radiation, from ingestion of radionuclides in food and from inhalation of radionuclides in air. A simple treatment is adopted to estimate radiation doses from drinking contaminated water. For Part (b), the data assembled in (a) provide the basis for developing statistical models for predicting radiation doses from weapon yields and trajectories of the radioactive clouds. The models are then applied to give the radiation doses to population centres following the tests in Hurricane and Totem, using their yields and trajectories. 71 refs., 20 tabs., 8 figs

  8. Preliminary evaluation of crisis-relocation fallout-shelter options. Volume 2. Detailed analysis

    Energy Technology Data Exchange (ETDEWEB)

    Santini, D.J.; Clinch, J.M.; Davis, F.H.; Hill, L.G.; Lynch, E.P.; Tanzman, E.A.; Wernette, D.R.

    1982-12-01

    This report presents a preliminary, detailed evaluation of various shelter options for use if the President orders crisis relocation of the US urban population because of strong expectation of a nuclear war. The availability of livable shelter space at 40 ft/sup 2/ per person (congregate-care space) by state is evaluated. Options are evaluated for construction of fallout shelters allowing 10 ft/sup 2/ per person - such shelters are designed to provide 100% survival at projected levels of radioactive fallout. The FEMA concept of upgrading existing buildings to act as fallout shelters can, in principle, provide adequate shelter throughout most of the US. Exceptions are noted and remedies proposed. In terms of upgrading existing buildings to fallout shelter status, great benefits are possible by turning away from a standard national approach and adopting a more site-specific approach. Existing FEMA research provides a solid foundation for successful crisis relocation planning, but the program can be refined by making suitable modifications in its locational, engineering, and institutionally specific elements.

  9. Assessment of radiation-induced cancer risks from the Chernobyl fallout in Finland

    International Nuclear Information System (INIS)

    Servomaa, A.; Komppa, T.; Suomela, M.

    1997-01-01

    Application of detailed radiation risk models to populations affected by radiation doses from the Chernobyl fallout allows forecasting and estimation of the consequences of the accident in countries far from the place of the accident, and comparison of the model estimates with epidemiological observations in low-dose conditions among large populations. 14 refs, 11 figs, 1 tab

  10. Assessment of radiation-induced cancer risks from the Chernobyl fallout in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Servomaa, A; Komppa, T; Suomela, M [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)

    1997-09-01

    Application of detailed radiation risk models to populations affected by radiation doses from the Chernobyl fallout allows forecasting and estimation of the consequences of the accident in countries far from the place of the accident, and comparison of the model estimates with epidemiological observations in low-dose conditions among large populations. 14 refs, 11 figs, 1 tab.

  11. From Pripyat to Paris, from grassroots memories to globalized knowledge production : the Politics of Chernobyl Fallout

    NARCIS (Netherlands)

    Kalmbach, K.; Bauer, S.; Kasperski, T.; MacDowell, Laurel

    In order to understand the politics of Chernobyl fallout, we need to approach these debates on different levels. Therefore, this chapter reflects on the following questions: In what ways has Chernobyl “materialized” for different people with different experiences? What role do individual and

  12. Upscaling the Use of Fallout Radionuclides in Soil Erosion and Sediment Budget Investigations: Addressing the Challenge

    Directory of Open Access Journals (Sweden)

    D.E. Walling

    2014-09-01

    Full Text Available The application of fallout radionuclides in soil erosion investigations and related sediment budget studies has provided a widely used tool for improving understanding of soil erosion and sediment transfer processes. However, most studies using fallout radionuclides undertaken to date have focussed on small areas. This focus on small areas reflects both the issues addressed and practical constraints associated with sample collection and analysis. Increasing acceptance of the important role of fine sediment in degrading aquatic habitats and in the transfer and fate of nutrients and contaminants within terrestrial and fluvial systems has emphasised the need to consider larger areas and the catchment or regional scale. The need to upscale existing approaches to the use of fallout radionuclides to larger areas represents an important challenge. This contribution provides a brief review of existing and potential approaches to upscaling the use of fallout radionuclides and presents two examples where such approaches have been successfully applied. These involve a national scale assessment of soil erosion rates in England and Wales based on 137Cs measurements and an investigation of the sediment budgets of three small/intermediate-size catchments in southern Italy.

  13. Transport and redistribution of Chernobyl fallout radionuclides by fluvial processes: some preliminary evidence

    International Nuclear Information System (INIS)

    Walling, D.E.; Bradley, S.B.

    1988-01-01

    Several measurements of 137 Cs concentrations in suspended sediment transported by the River Severn during the post-Chernobyl period and in recent channel and floodplain deposits along the river emphasise the potential significance of fluvial processes in the transport and concentration of fallout radionuclides. (author)

  14. Late radiation effects in Marshall Islanders exposed to fallout 28 years ago

    International Nuclear Information System (INIS)

    Conard, R.A.

    1984-01-01

    In 1954, following detonation of a megaton nuclear device at Bikini, an unfortunate accident occurred owing to an unpredicted shift in winds resulting in exposure to radioactive fallout of 250 Marshallese people, 28 American servicemen on atolls to the east, and 23 Japanese fishermen on their fishing vessel. In this presentation, medical findings in the exposed Marshallese noted over the past 28 years is briefly reviewed with particular emphasis on late effects on the thyroid gland. The Marshallese were too far distant from the detonation for any direct effects, and their exposure was due entirely to fallout radiation during the 2 days prior to evacuation. This consisted of penetrating whole-body gamma radiation, irradiation of the skin (principally beta radiation) from fallout deposited on the skin, and internal absorption of radionuclides from ingestion of contaminated food and water. The most serious internal exposure was that to the thyroid from radioiodines, which were relatively abundant in the fallout. 63 references, 1 figure, 4 tables

  15. Assessment of leukemia and thyroid disease in relation to fallout in Utah: Annual progress report

    International Nuclear Information System (INIS)

    1988-01-01

    This report contains the results of one year's work on the effects of fallout on the development of leukemia and thyroid disease in humans residing in Utah. Divided into 37 subphases, this report evaluates the development of predictive models, the use of dosimetry, and various cohort studies. (FI)

  16. Utilization of cesium-137 environmental contamination from fallout in erosion and sedimentation studies

    International Nuclear Information System (INIS)

    Guimaraes, M.F. da; Pessenda, L.C.R.; Fernandes, E.A.N.; Freire, O.; Nascimento Filho, V.F. do; Ferraz, E.S.B.

    1988-01-01

    The radioactivity of cesium-137 from fallout in different soils profiles for erosion and sedimentation studies are described. The potential of this technique for hydrographic basin in Piracicaba/Sao Paulo is evaluated. Due to the existence of natural radionuclides in soil, with energy near to cesium-137, the soil samples are determined by a high-purity Ge detectors. (author)

  17. Cancer incidence and risk in Alaskan natives exposed to radioactive fallout

    International Nuclear Information System (INIS)

    Stutzman, C.D.; Nelson, D.M.

    1986-01-01

    Cancer incidence in northern Alaskan villages exposed to radioactive fallout from nuclear weapons testing in the late 1950s and early 1960s was assessed using data from the Alaskan Native Tumor Registry. Previous studies have shown that cancer incidence in Alaskan natives differs from that in residents of the rest of the United States: rates of cancer of the nasopharynx and liver are higher in Alaskan native men and rates of cancer of the nasopharynx, gallbladder, cervix, and kidney are higher in Alaskan native women. Leukemia, breast cancer and bone sarcoma are the cancers most likely to result from fallout exposure in the Arctic, but the incidence of these cancers in the North Slope villages appeared to be lower than in either the entire Inuit population or the US population. The fallout radionuclides of potential health concern are cesium-137 and strontium-90, because of their abundance, long half-life, and chemical characteristics that facilitate transport through and concentration in the food chain and accumulation in sensitive tissues of the body. Radionuclide body burdens were determined in North Slope Inuit 25 years ago, because of their possible exposure to radioactive fallout via the lichen-caribou-man pathway. Cancer risk estimates have been calculated using highest average dose measurements from residents of Anaktuvuk Pass, under the assumption that peak exposure levels of the mid 1960s remained steady over the following 20 years. Worst-case estimates of expected cancer excess were calculated for leukemia, breast cancer and bone sarcoma

  18. Structure shielding from cloud and fallout gamma ray sources for assessing the consequences of reactor accidents

    International Nuclear Information System (INIS)

    Burson, Z.G.; Profio, A.E.

    1975-12-01

    Radiation shielding provided by transportation vehicles and structures typical of where people live and work were estimated for cloud and fallout gamma-ray sources resulting from a hypothetical reactor accident. Dose reduction factors are recommended for a variety of situations for realistically assessing the consequences of reactor accidents

  19. Preliminary evaluation of crisis-relocation fallout-shelter options. Volume 1. Summary

    International Nuclear Information System (INIS)

    Santini, D.J.; Clinch, J.M.; Davis, F.H.; Hill, L.G.; Lynch, E.P.; Tanzman, E.A.; Wernette, D.R.

    1982-03-01

    This report, prepared for the Federal Emergency Management Agency (FEMA), presents a summary evaluation of various shelter options for use in the case where the President orders crisis relocation of the US urban population because of strong expectation of a nuclear war. The availability of livable shelter space at 40 ft 2 per person (congregate-care space) by state is evaluated. Options are evaluated for construction of fallout shelters allowing 10 ft 2 per person - such shelters are designed to provide 100% survival at projected levels of radioactive fallout. The authors find that the FEMA concept of upgrading existing buildings to act as fallout shelters can, in principle, provide adequate shelter throughout most of the US. Exceptions are noted and remedies proposed. The authors also find that, in terms of upgrading existing buildings to fallout shelter status, great benefits are possible by turning away from a standard national approach and adopting a more site-specific approach. Existing FEMA research provides a solid foundation for successful crisis relocation planning, but the program can be refined by making suitable modifications in its locational, engineering, and institutionally specific elements

  20. Linking effects of anthropogenic debris to ecological impacts

    NARCIS (Netherlands)

    Browne, M.A.; Underwood, A.J.; Chapman, M.G.; Williams, R.; Thompson, R.C.; Franeker, van J.A.

    2015-01-01

    Accelerated contamination of habitats with debris has caused increased effort to determine ecological impacts. Strikingly, most work on organisms focuses on sublethal responses to plastic debris. This is controversial because (i) researchers have ignored medical insights about the mechanisms that

  1. European roe deer antlers as an environmental archive for fallout 236U and 239Pu

    International Nuclear Information System (INIS)

    Froehlich, M.B.; Steier, P.; Wallner, G.; Fifield, L.K.

    2016-01-01

    Anthropogenic 236 U and 239 Pu were measured in European roe deer antlers hunted between 1955 and 1977 which covers and extends beyond the period of intensive nuclear weapons testing (1954–1962). The antlers were hunting trophies, and hence the hunting area, the year of shooting and the approximate age of each animal is given. Uranium and plutonium are known to deposit in skeletal tissue. Since antler histology is similar to bone, both elements were expected in antlers. Furthermore, roe deer shed their antlers annually, and hence antlers may provide a time-resolved environmental archive for fallout radionuclides. The radiochemical procedure is based on a Pu separation step by anion exchange (Dowex 1 × 8) and a subsequent U purification by extraction chromatography using UTEVA ® . The samples were measured by Accelerator Mass Spectrometry at the VERA facility (University of Vienna). In addition to the 236 U and 239 Pu concentrations, the 240 Pu/ 239 Pu isotopic ratios were determined with a mean value of 0.172 ± 0.023 which is in agreement with the ratio of global fallout (∼0.18). Rather high 236 U/ 238 U ratios of the order of 10 −6 were observed. These measured ratios, where the 236 U arises only from global fallout, have implications for the use of the 236 U/ 238 U ratio as a fingerprint for nuclear accidents or releases from nuclear facilities. Our investigations have shown the potential to use antlers as a temporally resolved archive for the uptake of actinides from the environment. - Highlights: • Roe deer antlers were studied as an environmental archive for the retrospective study of fallout isotopes 236 U and 239 Pu. • The rather high 236 U/ 238 U ratios of about 10 −6 suggest 236 U as a fingerprint tool for nuclear material releases. • The 240 Pu/ 239 Pu atom ratio underpins global fallout as the main anthropogenic contributor in antlers.

  2. Monitoring the abundance of plastic debris in the marine environment

    OpenAIRE

    Ryan, Peter G.; Moore, Charles J.; van Franeker, Jan A.; Moloney, Coleen L.

    2009-01-01

    Plastic debris has significant environmental and economic impacts in marine systems. Monitoring is crucial to assess the efficacy of measures implemented to reduce the abundance of plastic debris, but it is complicated by large spatial and temporal heterogeneity in the amounts of plastic debris and by our limited understanding of the pathways followed by plastic debris and its long-term fate. To date, most monitoring has focused on beach surveys of stranded plastics and other litter. Infreque...

  3. Property measurements and inner state estimation of simulated fuel debris

    Energy Technology Data Exchange (ETDEWEB)

    Hirooka, S.; Kato, M.; Morimoto, K.; Washiya, T. [Japan Atomic Energy Agency, Ibaraki (Japan)

    2014-07-01

    Fuel debris properties and inner state such as temperature profile were evaluated by using analysis of simulated fuel debris manufactured from UO{sub 2} and oxidized zircaloy. The center of the fuel debris was expected to be molten state soon after the melt down accident of LWRs because power density was very high. On the other hand, the surface of the fuel debris was cooled in the water. This large temperature gradient may cause inner stress and consequent cracks were expected. (author)

  4. On the Solar System-Debris Disk Connecction

    OpenAIRE

    Moro-Martin, Amaya

    2007-01-01

    This paper emphasizes the connection between solar and extra-solar debris disks: how models and observations of the Solar System are helping us understand the debris disk phenomenon, and vice versa, how debris disks are helping us place our Solar System into context.

  5. Debris prevention system, radiation system, and lithograpic apparatus

    NARCIS (Netherlands)

    2009-01-01

    A debris prevention system is constructed and arranged to prevent debris that emanates from a radiation source from propagating with radiation from the radiation source into or within a lithographic apparatus. The debris prevention system includes an aperture that defines a maximum emission angle of

  6. Monitoring the abundance of plastic debris in the marine environment

    NARCIS (Netherlands)

    Ryan, P.G.; Moore, C.J. C.J.; Franeker, van J.A.; Moloney, C.L.

    2009-01-01

    Plastic debris has significant environmental and economic impacts in marine systems. Monitoring is crucial to assess the efficacy of measures implemented to reduce the abundance of plastic debris, but it is complicated by large spatial and temporal heterogeneity in the amounts of plastic debris and

  7. Fallout plutonium and natural radionuclides in annual bands of the coral Montastrea annularis, St. Croix, U.S. Virgin Islands

    International Nuclear Information System (INIS)

    Benninger, L.K.; Dodge, R.E.

    1986-01-01

    We have investigated the banded coral Montastrea annularis as a recorder of the history of fallout Pu in surface seawater. Thirty annual growth bands representing growth during 'coral years' 1951-1980, were subsampled from M. annularis collected at St. Croix, U.S. Virgin Islands. sup(239,240)Pu was finite in coral years 1954-1980, and the coral Pu record is very simply related to the fallout history of 90 Sr. Peaks in coral Pu in coral years 1959 and 1964 correspond to fallout peaks in 1959 and 1963, respectively. Peak broadening and time lags in the coral Pu record, as compared to the 90 Sr fallout record are consistent with retention of fallout Pu in surface seawater for about two years (characteristic removal time) during the period of major fallout, and possibly longer thereafter. The simplicity of the coral Pu record and its close correspondence with fallout history suggest that sup(239,240)Pu was incorporated into the coral skeleton with constant discrimination relative to Ca; the effects of speciation and oxidation state upon Pu incorporation are presently unknown. (author)

  8. Conditioning of metallic Magnox fuel element debris

    International Nuclear Information System (INIS)

    Kaye, C.J.

    1983-01-01

    The conditioning of metallic Magnox debris poses particular problems arising from its chemical reactivity and from the presence in discrete amounts of highly radioactive components. The treatment of this waste is currently being studied by the Central Electricity Generating Board. Following retrieval from store it is envisaged that the debris will be dried and comminuted to facilitate the removal for further storage of the highly active components from the bulk debris. A satisfactory means of sorting the debris appears to be by magnetic induction. The relatively low activity but potentially reactive Magnox will then be directly encapsulated prior to disposal off-site. Currently the only disposal route open for this waste is to the deep ocean. Matrices for encapsulating Magnox have been developed and others are under investigation. The desirable features of such matrices include low chemical reactivity and impermeability to water. The methods used to characterize the resultant waste forms and the results obtained are presented. Thermosetting polymers produce suitable waste forms for sea disposal, exhibiting high mechanical strength and resistance to leaching, and possessing very low chemical reactivity with respect to the Magnox waste. Low viscosity matrices are advantageous from the point of view of the process plant engineering as they enable the comminuted waste to be directly encapsulated. (author)

  9. Europium-155 in Debris from Nuclear Weapons

    DEFF Research Database (Denmark)

    Aarkrog, Asker; Lippert, Jørgen Emil

    1967-01-01

    The lithium-drifted germanium detector enables determination of europium-155 on a routine basis in environmental samples contaminated with debris from nuclear weapons. From measurements of europium-155, cesium-144, and strontium-90 in air filters collected between 1961 and 1966, the yield...

  10. Numerical modeling of the debris flows runout

    Directory of Open Access Journals (Sweden)

    Federico Francesco

    2017-01-01

    Full Text Available Rapid debris flows are identified among the most dangerous of all landslides. Due to their destructive potential, the runout length has to be predicted to define the hazardous areas and design safeguarding measures. To this purpose, a continuum model to predict the debris flows mobility is developed. It is based on the well known depth-integrated avalanche model proposed by Savage and Hutter (S&H model to simulate the dry granular materials flows. Conservation of mass and momentum equations, describing the evolving geometry and the depth averaged velocity distribution, are re-written taking into account the effects of the interstitial pressures and the possible variation of mass along the motion due to erosion/deposition processes. Furthermore, the mechanical behaviour of the debris flow is described by a recently developed rheological law, which allows to take into account the dissipative effects of the grain inelastic collisions and friction, simultaneously acting within a ‘shear layer’, typically at the base of the debris flows. The governing PDEs are solved by applying the finite difference method. The analysis of a documented case is finally carried out.

  11. Plastic Debris Is a Human Health Issue

    NARCIS (Netherlands)

    Vethaak, A.D.; Leslie, H.A.

    2016-01-01

    The global threat of highly persistent plastic waste accumulating and fragmenting in the world’s oceans, inland waters and terrestrial environments is becoming increasingly evident.1−3 Humans are being exposed to both plastic particles and chemical additives being released from the plastic debris of

  12. The Transport of Close-In Fallout Plutonium in the Northwest Pacific Ocean: Tracing the Water Mass Movement Using {sup 240}Pu/{sup 239}Pu Atom Ratio

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang-Han [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Hong, Gi-Hoon; Suk, Moon-Sik [Korea Ocean Research and Development Institute, Seoul (Korea, Republic of); Gastaud, J. [International Atomic Energy Agency, Marine Environment Laboratory (Monaco); La Rosa, J. [National Institute of Standards and Technology, Ionizing Radiation Division, Gaithersburg, Maryland (United States); Kim, Chul-Soo [Environmental Laboratories, International Atomic Energy Agency, Seibersdorf (Austria); Wyse, E. [New Brunswick Laboratory Argonne, IL (United States); Povinec, P. P. [Comenius University, Faculty of Mathematics and Physics, Bratislava (Slovakia)

    2013-07-15

    {sup 240}Pu/{sup 239}Pu atom ratios in seawater and surface sediment collected from the northwest (NW) Pacific Ocean from 1992 to 1997 were determined using ICP-sector field mass spectrometry (ICP-MS). In whole water columns, the atom ratios of {sup 240}Pu/{sup 239}Pu were higher than the global fallout ratio (0.18). It is noted that the atom ratios of {sup 240}Pu/2{sup 39}Pu in the seawater increase with depth. Such elevated {sup 240}Pu/{sup 239}Pu atom ratios indicate that the close-in fallout plutonium isotopes originating from the Pacific Proving Grounds (PPGs) due to the U.S. tests are prevailing in the seawater in the NW Pacific Ocean. However, the {sup 240}Pu/{sup 239}Pu atom ratios in the surface sediment from the NW Pacific Ocean varied with the sampling locations. As a consequence, this study will provide the information that the water mass along with the current plays a key role in driving the distribution of Pu and in transporting Pu from the PPGs to the far eastern marginal sea in the NW Pacific Ocean. (author)

  13. Optical Photometric Observations of GEO Debris

    Science.gov (United States)

    Seitzer, Patrick; Rodriquez-Cowardin, Heather M.; Barker, Edwin S.; Abercromby, Kira J.; Kelecy, Thomas M.; Horstman, Matt

    2010-01-01

    We report on a continuing program of optical photometric measurements of faint orbital debris at geosynchronous Earth orbit (GEO). These observations can be compared with laboratory studies of actual spacecraft materials in an effort to determine what the faint debris at GEO may be. We have optical observations from Cerro Tololo Inter-American Observatory (CTIO) in Chile of two samples of debris: 1. GEO objects discovered in a survey with the University of Michigan's 0.6-m aperture Curtis-Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the CTIO/SMARTS 0.9-m for orbits and photometry. Our goal is to determine 6 parameter orbits and measure colors for all objects fainter than R = 15 t11 magnitude that are discovered in the MODEST survey. 2. A smaller sample of high area to mass ratio (AMR) objects discovered independently, and acquired using predictions from orbits derived from independent tracking data collected days prior to the observations. Our optical observations in standard astronomical BVRI filters are done with either telescope, and with the telescope tracking the debris object at the object's angular rate. Observations in different filters are obtained sequentially. We have obtained 71 calibrated sequences of R-B-V-I-R magnitudes. A total of 66 of these sequences have 3 or more good measurements in all filters (not contaminated by star streaks or in Earth's shadow). Most of these sequences show brightness variations, but a small subset has observed brightness variations consistent with that expected from observational errors alone. The majority of these stable objects are redder than a solar color in both B-R and R-I. There is no dependence on color with brightness. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO 0.9-m observes in B, and MODEST in R. The CCD cameras are electronically linked together so that the start time and

  14. Photometric Studies of GEO Orbital Debris

    Science.gov (United States)

    Seitzer, Patrick; Rodriquez-Cowardin, Heather M.; Barker, Ed; Abercromby, Kira J.; Foreman, Gary; Horstman, Matt

    2009-01-01

    The photometric signature of a debris object can be useful in determining what the physical characteristics of a piece of debris are. We report on optical observations in multiple filters of debris at geosynchronous Earth orbit (GEO). Our sample is taken from GEO objects discovered in a survey with the University of Michigan's 0.6-m aperture Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the Cerro Tololo Inter- American Observatory (CTIO) 0.9-m for orbits and photometry. Our goal is to determine 6 parameter orbits and measure colors for all objects fainter than R=15th magnitude that are discovered in the MODEST survey. At this magnitude the distribution of observed angular rates changes significantly from that of brighter objects. There are two objectives: 1. Estimate the orbital distribution of objects selected on the basis of two observational criteria: brightness (magnitude) and angular rates. 2. Obtain magnitudes and colors in standard astronomical filters (BVRI) for comparison with reflectance spectra of likely spacecraft materials. What is the faint debris likely to be? More than 90 calibrated sequences of R-B-V-I-R magnitudes for a sample of 50 objects have been obtained with the CTIO 0.9-m. For objects that do not show large brightness variations, the colors are largely redder than solar in both B-R and R-I. The width of the color distribution may be intrinsic to the nature of the surfaces, but also could be that we are seeing irregularly shaped objects and measuring the colors at different times with just one telescope. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO 0.9-m observes in B, and MODEST in R. The CCD cameras are electronically linked together so that the start time and duration of observations are the same to better than 50 milliseconds. Thus the B-R color is a true measure of the surface of the debris piece facing the

  15. Laser space debris removal: now, not later

    Science.gov (United States)

    Phipps, Claude R.

    2015-02-01

    Small (1-10cm) debris in low Earth orbit (LEO) are extremely dangerous, because they spread the breakup cascade depicted in the movie "Gravity." Laser-Debris-Removal (LDR) is the only solution that can address both large and small debris. In this paper, we briefly review ground-based LDR, and discuss how a polar location can dramatically increase its effectiveness for the important class of sun-synchronous orbit (SSO) objects. No other solutions address the whole problem of large ( 1000cm, 1 ton) as well as small debris. Physical removal of small debris (by nets, tethers and so on) is impractical because of the energy cost of matching orbits. We also discuss a new proposal which uses a space-based station in low Earth orbit (LEO), and rapid, head-on interaction in 10- 40s rather than 4 minutes, with high-power bursts of 100ps, 355nm pulses from a 1.5m diameter aperture. The orbiting station employs "heat-capacity" laser mode with low duty cycle to create an adaptable, robust, dualmode system which can lower or raise large derelict objects into less dangerous orbits, as well as clear out the small debris in a 400-km thick LEO band. Time-average laser optical power is less than 15kW. The combination of short pulses and UV wavelength gives lower required energy density (fluence) on target as well as higher momentum coupling coefficient. This combination leads to much smaller mirrors and lower average power than the ground-based systems we have considered previously. Our system also permits strong defense of specific assets. Analysis gives an estimated cost of about 1k each to re-enter most small debris in a few months, and about 280k each to raise or lower 1-ton objects by 40km. We believe it can do this for 2,000 such large objects in about four years. Laser ablation is one of the few interactions in nature that propel a distant object without any significant reaction on the source.

  16. Losses of Sr/sup 90/, Sr/sup 89/, and I/sup 131/ from fallout-contaminated plants

    Energy Technology Data Exchange (ETDEWEB)

    Martin, W E

    1964-11-01

    During the early period following local fallout, and during periods of maximal worldwide fallout, the entry of radionuclides into terrestrial food-chains is due primarily to the external contamination of plants and secondarily to the uptake of radionuclides from contaminated soil. Studies were undertaken to estimate the rates of radionuclide loss from fallout-contaminated vegetation and hence from the diets of herbivores living in a fallout field. On the fifth, fifteenth, thirtieth, and sixtieth days after an underground nuclear explosion (Operation Sedan) at the Nevada Test Site, plant samples were collected from twenty representative locations in the fallout field and analyzed to determined the concentrations (pc/g dry wt) of /sup 90/Sr, /sup 89/Sr, and /sup 131/I at the times of collections. While the radioactive half lives of /sup 90/Sr, /sup 89/Sr, and /sup 131/I are approximately 27.7 years, 53 days, and 8.04 days respectively, their average effective half-lives on fallout-contaminated plants, during the period from 5 to 30 days after the detonation, were 27.8 days, 17.8 days, and 5.0 days respectively. Losses of /sup 90/Sr were attributed to radioactive decay and to the removal of fallout particles and foliage by wind and/or other mechanical disturbances. Losses of /sup 90/Sr and /sup 89/Sr were attributed to radioactive decay and to the removal of fallout particles and foliage by wind and/or other mechanical disturbances. Losses of /sup 131/I were attributed to radioactive decay, to mechanical disturbance, and to the vaporization of /sup 131/I from the fallout particles retained on foliage.

  17. NASA's New Orbital Debris Engineering Model, ORDEM2010

    Science.gov (United States)

    Krisko, Paula H.

    2010-01-01

    This paper describes the functionality and use of ORDEM2010, which replaces ORDEM2000, as the NASA Orbital Debris Program Office (ODPO) debris engineering model. Like its predecessor, ORDEM2010 serves the ODPO mission of providing spacecraft designers/operators and debris observers with a publicly available model to calculate orbital debris flux by current-state-of-knowledge methods. The key advance in ORDEM2010 is the input file structure of the yearly debris populations from 1995-2035 of sizes 10 micron - 1 m. These files include debris from low-Earth orbits (LEO) through geosynchronous orbits (GEO). Stable orbital elements (i.e., those that do not randomize on a sub-year timescale) are included in the files as are debris size, debris number, material density, random error and population error. Material density is implemented from ground-test data into the NASA breakup model and assigned to debris fragments accordingly. The random and population errors are due to machine error and uncertainties in debris sizes. These high-fidelity population files call for a much higher-level model analysis than what was possible with the populations of ORDEM2000. Population analysis in the ORDEM2010 model consists of mapping matrices that convert the debris population elements to debris fluxes. One output mode results in a spacecraft encompassing 3-D igloo of debris flux, compartmentalized by debris size, velocity, pitch, and yaw with respect to spacecraft ram direction. The second output mode provides debris flux through an Earth-based telescope/radar beam from LEO through GEO. This paper compares the new ORDEM2010 with ORDEM2000 in terms of processes and results with examples of specific orbits.

  18. [Comparative analysis of the radionuclide composition in fallout after the Chernobyl and the Fukushima accidents].

    Science.gov (United States)

    Kotenko, K V; Shinkarev, S M; Abramov, Iu V; Granovskaia, E O; Iatsenko, V N; Gavrilin, Iu I; Margulis, U Ia; Garetskaia, O S; Imanaka, T; Khoshi, M

    2012-01-01

    The nuclear accident occurred at Fukushima Dai-ichi Nuclear Power Plant (NPP) (March 11, 2011) similarly to the accident at the Chernobyl NPP (April 26, 1986) is related to the level 7 of the INES. It is of interest to make an analysis of the radionuclide composition of the fallout following the both accidents. The results of the spectrometric measurements were used in that comparative analysis. Two areas following the Chernobyl accident were considered: (1) the near zone of the fallout - the Belarusian part of the central spot extended up to 60 km around the Chernobyl NPS and (2) the far zone of the fallout--the "Gomel-Mogilev" spot centered 200 km to the north-northeast of the damaged reactor. In the case of Fukushima accident the near zone up to about 60 km considered. The comparative analysis has been done with respect to refractory radionuclides (95Zr, 95Nb, 141Ce, 144Ce), as well as to the intermediate and volatile radionuclides 103Ru, 106Ru, 131I, 134Cs, 137Cs, 140La, 140Ba and the results of such a comparison have been discussed. With respect to exposure to the public the most important radionuclides are 131I and 137Cs. For the both accidents the ratios of 131I/137Cs in the considered soil samples are in the similar ranges: (3-50) for the Chernobyl samples and (5-70) for the Fukushima samples. Similarly to the Chernobyl accident a clear tendency that the ratio of 131I/137Cs in the fallout decreases with the increase of the ground deposition density of 137Cs within the trace related to a radioactive cloud has been identified for the Fukushima accident. It looks like this is a universal tendency for the ratio of 131I/137Cs versus the 137Cs ground deposition density in the fallout along the trace of a radioactive cloud as a result of a heavy accident at the NPP with radionuclides releases into the environment. This tendency is important for an objective reconstruction of 131I fallout based on the results of 137Cs measurements of soil samples carried out at

  19. Use of experimental plots for assessing Chernobyl-derived fallout of 137CS in France

    International Nuclear Information System (INIS)

    Bonte, Ph.; Sogon, S.; Bourgeois, S.; Terce, M.; Morel, Ch.

    2004-01-01

    Caesium-137 ( 137 Cs) is widely used for the determination of soil erosion and sedimentation rates. However, in Europe, if the additional inputs of 137 Cs fallout associated with the Chernobyl accident have given a supplementary mark to know the chronological history of buried sediments in rivers or wetlands, they have considerably complicated the interpretation of 137 Cs inventories used for estimating soil redistribution on slopes. In fact, determination of Chernobyl-derived fallout 137 Cs is problematic because very few sites have been correctly sampled at the moment of the accident. During the ten years after, it was possible to estimate the fallout measuring the 134 Cs activity for estimating 137 Cs ( 137 Cs / 134 Cs 2.0 at the time of the accident). But these measurements are extremely rare, whereas it should be the more accurate method to resolve this question. The more used solution is to use model based on atmospheric circulation and rain precipitation, the main part of fallout been due to atmospheric washing by the rain. Other solution is to compare 137 Cs specific activity of soil samples collected after the accident and older samples. Then, we choose a set of soil samples collected on several experimental plots at different places in France, and sampled before and after the Chernobyl accident, to determine the part of contamination linked to this 137 Cs fallout event with a simple comparison of their 137 Cs specific activity. In fact, national French institutes working on agronomy maintain experimental plots, with varied surface area (1 m 2 10 m 2 or larger), for monitoring of soil physics and chemistry evolution. Nine sites were studied: two of them close to Paris, one 100 km east of Paris, 3 in Loire basin and 3 in south west, in the Pyrenees Atlantic. These measurements confirm the influence of the Chernobyl radioactive plume over the Paris Basin concerning the 137 Cs fallout. The 137 Cs specific activity is, on average, 25% (from 18 to 35% at

  20. Tracking Radioactive Fallout from the Fukushima Dai-ichi Accident in Arctic Snow

    Science.gov (United States)

    Osterberg, E. C.; Thompson, J.; Landis, J.; Albert, M. R.; Campbell, S. W.; Hawley, R. L.; Virginia, R. A.

    2011-12-01

    The March 11, 2011 magnitude 9.0 Tohoku, Japan earthquake produced a tsunami that inundated the Fukushima Dai-ichi nuclear power plant and led to the accidental release of radioactive 131I, 132Te, 134Cs, and 137Cs to the atmosphere. The Japanese Nuclear Safety Commission estimates that 12,000 TBq of 137Cs were released to the atmosphere during the incident, which represents ~14% of the total estimated 137Cs emission from the Chernobyl disaster in April 1986. Measurements of airborne radiation collected at the Fukushima plant illustrate that >50% of the total emitted radiation was released on March 15 and 16 associated with explosions and fires at reactor units 1, 2, and 4, and 70% was emitted in the first 5 days of the event. The source of the radiation is thus well constrained in time and space, providing an opportunity to better understand long-range atmospheric transport processes from Asia to the Arctic, while also assessing the magnitude of the fallout in the Arctic. Here we describe the 137Cs and 134Cs fallout flux near Thule, Greenland (1700 m a.s.l.), at Summit (3200 m a.s.l.), Greenland, and within Denali National Park, Alaska (2400-3900 m a.s.l.) based on series of large-volume (5-15 l) snow pit samples collected in June and July, 2011. In addition to assessing the spatial variability of Fukushima fallout in the Arctic, the elevation range of samples allows for an analysis of any vertical heterogeneity in fallout transport and deposition. Major ion concentrations and stable water isotope ratios are used to confirm the seasonal timing of the Fukushima fallout horizon in the snowpack. Radiocesium was concentrated and isolated from the snow pit meltwater using the well-established ammonium phosphomolybdate (AMP) adsorption method, and 134Cs and 137Cs concentrations were measured using gamma spectrometry with a Canberra 3523 well-type intrinsic Ge-detector at the Dartmouth College Short-Lived Isotope Laboratory. NOAA HYPLIT atmospheric forward

  1. Closure Report for Corrective Action Unit 425: Area 9 Main Lake Construction Debris Disposal Area, Tonopah Test Range, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    K. B. Campbell

    2003-03-01

    Corrective Action Unit (CAU) 425 is located on the Tonopah Test Range, approximately 386 kilometers (240 miles) northwest of Las Vegas, Nevada. CAU 425 is listed in the Federal Facility Agreement and Consent Order (FFACO, 1996) and is comprised of one Corrective Action Site (CAS). CAS 09-08-001-TA09 consisted of a large pile of concrete rubble from the original Hard Target and construction debris associated with the Tornado Rocket Sled Tests. CAU 425 was closed in accordance with the FFACO and the Nevada Division of Environmental Protection-approved Streamlined Approach for Environmental Restoration Plan for CAU 425: Area 9 Main Lake Construction Debris Disposal Area, Tonopah Test Range, Nevada (U.S. Department of Energy, Nevada Operations Office, 2002). CAU 425 was closed by implementing the following corrective actions: The approved corrective action for this unit was clean closure. Closure activities included: (1) Removal of all the debris from the site. (2) Weighing each load of debris leaving the job site. (3) Transporting the debris to the U.S. Air Force Construction Landfill for disposal. (4) Placing the radioactive material in a U.S. Department of Transportation approved container for proper transport and disposal. (5) Transporting the radioactive material to the Nevada Test Site for disposal. (6) Regrading the job site to its approximate original contours/elevation.

  2. Protecting AREVA ATRIUM™ BWR fuel from debris fretting failure

    International Nuclear Information System (INIS)

    Cole, Steven E.; Garner, Norman L.; Lippert, Hans-Joachim; Graebert, Rüdiger; Mollard, Pierre; Hahn, Gregory C.

    2014-01-01

    Historically, debris fretting has been the leading cause of fuel rod failure in BWR fuel assemblies, costing the industry millions of dollars in lost generation and negatively impacting the working area of plant site personnel. In this paper the focus will be on recent BWR fuel product innovation designed to eliminate debris related failures. Experience feedback from more than three decades of operation history with non-line-of-sight FUELGUARD™ lower tie plate debris filters will be presented. The development and relative effectiveness of successive generations of filtration technology will be discussed. It will be shown that modern, state of the art debris filters are an effective defense against debris fretting failure. Protective measures extend beyond inlet nozzle debris filters. The comprehensive debris resistance features built into AREVA’s newest fuel design, the ATRIUM™ 11, reduce the overall risk of debris entrapment as well as providing a degree of protection from debris that may fall down on the fuel assembly from above, e.g., during refueling operations. The positive recent experience in a debris sensitive plant will be discussed showing that the combination of advanced fuel technology and a robust foreign material exclusion program at the reactor site can eliminate the debris fretting failure mechanism. (author)

  3. Space Transportation System Liftoff Debris Mitigation Process Overview

    Science.gov (United States)

    Mitchell, Michael; Riley, Christopher

    2011-01-01

    Liftoff debris is a top risk to the Space Shuttle Vehicle. To manage the Liftoff debris risk, the Space Shuttle Program created a team with in the Propulsion Systems Engineering & Integration Office. The Shutt le Liftoff Debris Team harnesses the Systems Engineering process to i dentify, assess, mitigate, and communicate the Liftoff debris risk. T he Liftoff Debris Team leverages off the technical knowledge and expe rtise of engineering groups across multiple NASA centers to integrate total system solutions. These solutions connect the hardware and ana lyses to identify and characterize debris sources and zones contribut ing to the Liftoff debris risk. The solutions incorporate analyses sp anning: the definition and modeling of natural and induced environmen ts; material characterizations; statistical trending analyses, imager y based trajectory analyses; debris transport analyses, and risk asse ssments. The verification and validation of these analyses are bound by conservative assumptions and anchored by testing and flight data. The Liftoff debris risk mitigation is managed through vigilant collab orative work between the Liftoff Debris Team and Launch Pad Operation s personnel and through the management of requirements, interfaces, r isk documentation, configurations, and technical data. Furthermore, o n day of launch, decision analysis is used to apply the wealth of ana lyses to case specific identified risks. This presentation describes how the Liftoff Debris Team applies Systems Engineering in their proce sses to mitigate risk and improve the safety of the Space Shuttle Veh icle.

  4. [Research progress in post-fire debris flow].

    Science.gov (United States)

    Di, Xue-ying; Tao, Yu-zhu

    2013-08-01

    The occurrence of the secondary disasters of forest fire has significant impacts on the environment quality and human health and safety. Post-fire debris flow is one of the most hazardous secondary disasters of forest fire. To understand the occurrence conditions of post-fire debris flow and to master its occurrence situation are the critical elements in post-fire hazard assessment. From the viewpoints of vegetation, precipitation threshold and debris flow material sources, this paper elaborated the impacts of forest fire on the debris flow, analyzed the geologic and geomorphic conditions, precipitation and slope condition that caused the post-fire debris flow as well as the primary mechanisms of debris-flow initiation caused by shallow landslide or surface runoff, and reviewed the research progress in the prediction and forecast of post-fire debris flow and the related control measures. In the future research, four aspects to be focused on were proposed, i. e., the quantification of the relationships between the fire behaviors and environmental factors and the post-fire debris flow, the quantitative research on the post-fire debris flow initiation and movement processes, the mechanistic model of post-fire debris flow, and the rapid and efficient control countermeasures of post-fire debris flow.

  5. Impact Forces from Tsunami-Driven Debris

    Science.gov (United States)

    Ko, H.; Cox, D. T.; Riggs, H.; Naito, C. J.; Kobayashi, M. H.; Piran Aghl, P.

    2012-12-01

    Debris driven by tsunami inundation flow has been known to be a significant threat to structures, yet we lack the constitutive equations necessary to predict debris impact force. The objective of this research project is to improve our understanding of, and predictive capabilities for, tsunami-driven debris impact forces on structures. Of special interest are shipping containers, which are virtually everywhere and which will float even when fully loaded. The forces from such debris hitting structures, for example evacuation shelters and critical port facilities such as fuel storage tanks, are currently not known. This research project focuses on the impact by flexible shipping containers on rigid columns and investigated using large-scale laboratory testing. Full-scale in-air collision experiments were conducted at Lehigh University with 20 ft shipping containers to experimentally quantify the nonlinear behavior of full scale shipping containers as they collide into structural elements. The results from the full scale experiments were used to calibrate computer models and used to design a series of simpler, 1:5 scale wave flume experiments at Oregon State University. Scaled in-air collision tests were conducted using 1:5 scale idealized containers to mimic the container behavior observed in the full scale tests and to provide a direct comparison to the hydraulic model tests. Two specimens were constructed using different materials (aluminum, acrylic) to vary the stiffness. The collision tests showed that at higher speeds, the collision became inelastic as the slope of maximum impact force/velocity decreased with increasing velocity. Hydraulic model tests were conducted using the 1:5 scaled shipping containers to measure the impact load by the containers on a rigid column. The column was instrumented with a load cell to measure impact forces, strain gages to measure the column deflection, and a video camera was used to provide the debris orientation and speed. The

  6. Effects of creating two forest structures and using prescribed fire on coarse woody debris in northeastern California, USA

    Science.gov (United States)

    Fabian C. C. Uzoh; Carl N. Skinner

    2009-01-01

    Little is known about the dynamics of coarse woody debris (CWD) in forests that were originally characterized by frequent, low-moderate intensity fires. We investigated effects of prescribed burning at the Blacks Mountain Experimental Forest in northeastern California following creation of two stand structure conditions: 1) high structural diversity (HiD) that included...

  7. Quantifying volume loss from ice cliffs on debris-covered glaciers using high-resolution terrestrial and aerial photogrammetry

    NARCIS (Netherlands)

    Brun, Fanny; Buri, Pascal; Miles, Evan S.; Wagnon, Patrick; Steiner, J.F.; Berthier, Etienne; Ragettli, S.; Kraaijenbrink, P.D.A.; Immerzeel, W.W.; Pellicciotti, Francesca

    Mass losses originating from supraglacial ice cliffs at the lower tongues of debris-covered glaciers are a potentially large component of the mass balance, but have rarely been quantified. In this study, we develop a method to estimate ice cliff volume losses based on high-resolution topographic

  8. Fire debris analysis for forensic fire investigation using laser induced breakdown spectroscopy (LIBS)

    Science.gov (United States)

    Choi, Soojin; Yoh, Jack J.

    2017-08-01

    The possibility verification of the first attempt to apply LIBS to arson investigation was performed. LIBS has capabilities for real time in-situ analysis and depth profiling. It can provide valuable information about the fire debris that are complementary to the classification of original sample components and combustion residues. In this study, fire debris was analyzed to determine the ignition source and existence of a fire accelerant using LIBS spectra and depth profiling analysis. Fire debris chemical composition and carbon layer thickness determines the possible ignition source while the carbon layer thickness of combusted samples represents the degree of sample carbonization. When a sample is combusted with fire accelerants, a thicker carbon layer is formed because the burning rate is increased. Therefore, depth profiling can confirm the existence of combustion accelerants, which is evidence of arson. Also investigation of fire debris by depth profiling is still possible when a fire is extinguished with water from fire hose. Such data analysis and in-situ detection of forensic signals via the LIBS may assist fire investigation at crime scenes.

  9. Characterization of plastic beach debris finalized to its removal: a proposal for a recycling scheme.

    Science.gov (United States)

    Pietrelli, Loris; Poeta, Gianluca; Battisti, Corrado; Sighicelli, Maria

    2017-07-01

    Characterization of beach debris is crucial to assess the strategy to answer questions such as recycling. With the aim to assess its use in a recycling scheme, in this note, we carried out a physical and chemical characterization of plastic litter from a pilot beach in Central Italy, using the FT-IR spectroscopy and thermoanalysis. Fourteen polymers, having mainly thermoplastic origin, were identified; among them, the most represented are polyethylene (41.7%) and polypropylene (36.9%). Chemical and mechanical degradation were clearly observed by an IR spectrum. The thermogravimetric analysis curve of the plastic blend shows the melting point at 120-140 °C, and degradation occurs almost totally in a one-step process within 300-500 °C. The high heating value of the plastic debris is 43.9 MJ kg -1 . Polymer blends obtained by beach debris show mechanical properties similar to the virgin high-density polyethylene polymer. Following the beach plastic debris characterization, a recycling scheme was suggested.

  10. Using Light Curves to Characterize Size and Shape of Pseudo-Debris

    Science.gov (United States)

    Rodriquez, Heather M.; Abercromby, Kira J.; Jarvis, Kandy S.; Barker, Edwin

    2006-01-01

    Photometric measurements were collected for a new study aimed at estimating orbital debris sizes based on object brightness. To obtain a size from optical measurements the current practice is to assume an albedo and use a normalized magnitude to calculate optical size. However, assuming a single albedo value may not be valid for all objects or orbit types; material type and orientation can mask an object s true optical cross section. This experiment used a CCD camera to record data, a 300 W Xenon, Ozone Free collimated light source to simulate solar illumination, and a robotic arm with five degrees of freedom to move the piece of simulated debris through various orientations. The pseudo-debris pieces used in this experiment originate from the European Space Operations Centre s ESOC2 ground test explosion of a mock satellite. A uniformly illuminated white ping-pong ball was used as a zero-magnitude reference. Each debris piece was then moved through specific orientations and rotations to generate a light curve. This paper discusses the results of five different object-based light curves as measured through an x-rotation. Intensity measurements, from which each light curve was generated, were recorded in five degree increments from zero to 180 degrees. Comparing light curves of different shaped and sized pieces against their characteristic length establishes the start of a database from which an optical size estimation model will be derived in the future.

  11. Stratigraphic reconstruction of the 13 ka BP debris avalanche deposit at Colima volcano (Mexico): effect of climatic conditions on the flow mobility

    Science.gov (United States)

    Roverato, M.; Capra, L.

    2010-12-01

    Colima volcano is an andesitic stratovolcano located in the western part of the Trans-Mexican Volcanic Belt (TMVB) and at the southern end of the N-S trending Colima graben, about 70 km from the Pacific Ocean coast. It is probably the most active Mexican volcano in historic time and one of the most active of North America. Colima volcano yielded numerous partial edifice collapses with emplacement of debris avalanche deposits (DADs) of contrasting volume, morphology, texture and origin. This work has the aim to provide the evidences of how the climatic condition during the 13 ka flank collapse of the Colima volcano affected the textural characteristic and the mobility of the debris avalanche and debris flow originated from this event that occurred just after the Last Glacial Maximum in Mexico (18.4-14.5 ka 14C BP with snow line at 3600 m a.s.l. up to 13 ka BP). The 13,000 yrs old debris avalanche deposit, here named Tonila (TDAD) presents the typical debris avalanche textural characteristics (angular to sub-angular clasts, coarse matrix, jigsaw fit) but at approximately 13 km from the source, the deposit transforms to an hybrid phase with debris avalanche fragments imbedded in a finer, homogenous and indurated matrix more similar to a debris flow deposit. The debris avalanche deposit is directly overly by debris flows, often more than 10 m thick that contains large amount of logs from pine tree, mostly accumulated toward the base and imbricated down flow. Fluvial deposits also occur throughout all successions, representing periods of stream and river reworking highly localized and re-establishment. All these evidences point to the presence of water in the mass previous to the failure. The event here described represent an anomalous event between the previously described deposit associated to volcanic complex, and evidence as climatic condition can alter and modifies the depositional sequences incrementing the hazard.

  12. Comparison of experimental and calculated shielding factors for modular buildings in a radioactive fallout scenario

    DEFF Research Database (Denmark)

    Hinrichsen, Yvonne; Finck, Robert; Östlund, Karl

    2018-01-01

    building used was a standard prefabricated structure obtained from a commercial manufacturer. Four reference positions for the gamma radiation detectors were used inside the building. Theoretical dose rate calculations were performed using the Monte Carlo code MCNP6, and additional calculations were......Experimentally and theoretically determined shielding factors for a common light construction dwelling type were obtained and compared. Sources of the gamma-emitting radionuclides 60Co and 137Cs were positioned around and on top of a modular building to represent homogeneous fallout. The modular...... performed that compared the shielding factor for 137Cs and 134Cs. This work demonstrated the applicability of using MCNP6 for theoretical calculations of radioactive fallout scenarios. Furthermore, the work showed that the shielding effect for modular buildings is almost the same for 134Cs as for 137Cs....

  13. Radioactive rare earths from fallout for study of particle movement in the sea

    International Nuclear Information System (INIS)

    Sugihara, Thomas T.; Bowen, Vaughan T.

    1962-01-01

    As part of an extensive study of the distribution of long-lived radionuclides from fallout in the Atlantic Ocean, a large number of measurements of cerium-144 and promethium-147 concentration have been made. Comparison of these concentrations as they vary both horizontally and vertically, with simultaneously measured concentrations of strontium-90, indicates that the rare earths are generally depleted in surface water, by comparison with the nuclides known to be soluble. This observation, coupled with frequent observation of rare-earth enrichment at depth, leads us to postulate rapid vertical transport of rare earths by attachment to particles undergoing sedimentation. This is completely plausible in terms of the 'radiocolloid' behaviour generally observed for rare earths at sea-water pH. An attempt is made to interpret this study in the overall picture of the marine geochemistry of the trivalent cations, as well as to emphasize the unique and generally useful aspects of the fallout tracer experiment. (author) [fr

  14. Detection of hot fallout on Taiwan in the period 1971-1975

    International Nuclear Information System (INIS)

    Weng, P.S.; Chu, T.C.; Hsu, C.N.; Su, S.J.

    1977-01-01

    The observation of fallout during the period of 1971-1975 is presented. Relatively high activity from nuclear tests at Lop Nor off mainland China was detected twice in this period. The gamma-ray spectrum of the hot fallout after the 11th nuclear test is given. The high activity peaks in the figures included are indicated with corresponding dates and sequence number of the tests for easy identification and comparison. The calibration of thermoluminescent dosimeters for the low exposure rates is presented. The gross beta activities are much more likely to build up in milk and surface water samples. Their intensity and duration are more significant than other foodstuff samples, and the timing of their appearance is more predictable. (author)

  15. Atmospheric lead fallout over the last century recorded in Gulf of Lions sediments (Mediterranean Sea)

    International Nuclear Information System (INIS)

    Miralles, J. . E-mail jmiralles@wanadoo.fr; Veron, A.J.; Radakovitch, O.; Deschamps, P.; Tremblay, T.; Hamelin, B.

    2006-01-01

    Six marine sediment cores from the Gulf of Lions continental slope (700-1700 m water depth) were analyzed for stable lead isotopes and 21 Pb geochronology in order to reconstruct lead atmospheric fallout pattern during the last century. The detrital lead contribution is 25 μg g -1 and the mean sediment anthropogenic inventory is 110 ± 7 μg cm -2 , a little bit higher than atmospheric deposition estimate. Anthropogenic lead accumulation in sediments peaked in early 1970s (1973 ± 2) in agreement with lead emissions features. For the period 1986-1997, the sediment signal also reflect the decrease of atmospheric lead described by independent atmospheric fallout investigations. The anthropogenic Pb deposition in the late 1990s was similar to the 1950s deposition, attesting thus of the output of European environmental policies

  16. Use of mosses and lichens for regional mapping of 137Cs fallout from the Chernobyl accident

    International Nuclear Information System (INIS)

    Steinnes, E.; Njaastad, O.

    1992-01-01

    The lichens Hypogymnia physodles and Cladonia stellaris and the moss Hylocomium splendens were studied for potential use af biomonitors of the regional distribution of 137 Cs fallout in Norway from the Chernobyl accident. While Hylocomium splendens and Cladonia stellaris showed reasonable mutual agreement, the activities recorded in the epiphytic species Hypogymnia physodes were not consistent with those of the other species, and depended strongly on whether sampling was carried out on conifers or birch. The geographical distribution of 137 Cs in the two former species was in satisfactory agreement with depostion figures obtained from analysis of surface soil, considering the heterogeneous depostion pattern of Chernobyl radioactivity. Both Hylocomium splendens and Cladonia stellaris appear well suited for regional mapping of 137 Cs fallout from nuclear accidents. Regional heavy metal deposition surveys employing Hylocomium splendens might be extended to include radionuclides if desirable. (au) (21 refs.)

  17. RESUME95 Nordic field test of mobile equipment for nuclear fall-out monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Bourgeois, C.; Bresson, J.; Chiffot, T.; Guillot, L. [Centre d`Etudes de Valduc, Direction des Applications Militaires, Commissaiat a L`Energie Atomique, Tille (France)

    1997-12-31

    Nordic Safety Research (NKS) organised in August 1995 a field test of various techniques and instrumentation for monitoring radioactive fall-out. In an emergency situation, after a major release of radioactive material, many different measuring systems are going to be used, ranging from small hand hold intensitometer to complex spectrometer systems. In this test the following type of equipment were tested: Airborne spectrometers; Carborne spectrometers and dose rate meters; In situ spectrometers and intensitometers. Helinuc team was equipped of an airborne system and of a germanium device for in situ measurements. Different tasks were specified for each team: Mapping caesium fall-out and natural activity over two areas of 18 and 5 km{sup 2}; Research of hidden sources. For measurements and data processing the respect of time allowed was strictly controlled for testing the ability of each team. (au).

  18. Airborne fallout mapping of {sup 137}Cs Finnish defence forces team

    Energy Technology Data Exchange (ETDEWEB)

    Kettunen, M.; Heininen, T. [Finnish Defence Forces Research Centre, Lakiala (Finland); Pulakka, M. [Finnish Air Force Depot, Tampere (Finland)

    1997-12-31

    The main task of the team was to create a fallout map of {sup 137}Cs in a specified area in Padasjoki Auttoinen village. The team used an MI-8 helicopter of the Finnish Air Force. The team had an HPGe system (relative efficiency 70%) to measure nuclide specific ground contamination level. For navigation the team took advantage of the DGPS service provided by Finnish Broadcasting company utilizing the RDS-channel to get position accuracy within 2 meters. The correction signal is reachable nationwide on the FM transmitter network. The system produced a distribution map for {sup 40}K and fallout maps for {sup 134,137}Cs using a Micro Station Program with TerraModeler application. The maximum measured {sup 137}Cs ground contamination exceeded 130-140 kBqm{sup -2}. (au).

  19. Airborne fallout mapping of {sup 137}Cs - STUK/HUT team

    Energy Technology Data Exchange (ETDEWEB)

    Nikkinen, M.; Aarnio, P. [Helsinki Univ. of Technology, Espoo (Finland); Honkamaa, T.; Tiilikainen, H. [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)

    1997-12-31

    The task of the team was to create a fallout map of {sup 137}Cs on a specified area in Padasjoki Auttoinen village. The team used AB-420 helicopter of the Finnish Frontier Guard. The team had two measuring systems: HPGe system (relative efficiency 18%) and NaI system (5`x5`). Both systems produced similar maps. The average {sup 137}Cs fallout within the area (lakes and ponds included) was 88 kBq m{sup -2,} the maximum value being 161 kBq m{sup -2}. In an emergency the HPGe is superior to NaI because of its better energy resolution, giving possibility to obtain nuclide-specific results. (au).

  20. Carbon-14 activity of fallout in Araucaria angustifolia annual growth rings, from Arapoti, Parana State, Brazil

    International Nuclear Information System (INIS)

    Lisi, Claudio Sergio; Pessenda, Luiz Carlos Ruiz; Tomazello Filho, Mario

    2000-01-01

    During the period of nuclear tests between 1950 and 1960, an input of artificial 14 C (fallout effect) occurred in the natural reservoirs. 14 C determinations in the Northern Hemisphere showed values of Δ 14 C up to 960 in the year of 1964. To determine the fallout 14 C activity in Brazil, wood samples from Araucaria angustifolia (Bert.) O. Kuntze, Araucariaceae, were collected in Arapoti-PR (24 deg 11 S , 49 deg 58 O ). The annual tree rings were selected by dendrochronology. The cellulose was extracted and its 14 C activity determined by liquid scintillation method. The results showed a significant increase of the Δ 14 C up to 590 in 1965, about 60% higher than the natural activity, gradually decreasing after the end of nuclear tests. These results were correlated with those obtained in the Northen Hemisphere and will be used in the studies of CO 2 mechanisms distribuition to the atmosphere and other natural reservoirs. (author)

  1. Retention of simulated fallout nuclides in agricultural crops. 1. Experiments on leys

    International Nuclear Information System (INIS)

    Eriksson, Aake; Rosen, K.; Haak, E.

    1998-01-01

    Experiments with artificial wet depositions of 134 Cs and 85 Sr during the growth period were carried out. The studies are complementary to the experiences after the Chernobyl fallout. The aim was to get a description of the relative transfer to the harvest products of new clover-grass leys and old grass leys after initial depositions of tracer nuclides at different times during the growth period. The reduction in transfer with time, from deposition to sampling, depends partly on dilution by growth and partly on fall-off to the ground. The reduction half-time for the nuclide content showed a range 10 - 14 days. The data obtained in the experiments can extend the basis for prediction of the consequences of fallout events at different times to new as well as to old leys in the field

  2. RESUME95 Nordic field test of mobile equipment for nuclear fall-out monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Bourgeois, C; Bresson, J; Chiffot, T; Guillot, L [Centre d` Etudes de Valduc, Direction des Applications Militaires, Commissaiat a L` Energie Atomique, Tille (France)

    1998-12-31

    Nordic Safety Research (NKS) organised in August 1995 a field test of various techniques and instrumentation for monitoring radioactive fall-out. In an emergency situation, after a major release of radioactive material, many different measuring systems are going to be used, ranging from small hand hold intensitometer to complex spectrometer systems. In this test the following type of equipment were tested: Airborne spectrometers; Carborne spectrometers and dose rate meters; In situ spectrometers and intensitometers. Helinuc team was equipped of an airborne system and of a germanium device for in situ measurements. Different tasks were specified for each team: Mapping caesium fall-out and natural activity over two areas of 18 and 5 km{sup 2}; Research of hidden sources. For measurements and data processing the respect of time allowed was strictly controlled for testing the ability of each team. (au).

  3. Airborne fallout mapping of {sup 137}Cs - STUK/HUT team

    Energy Technology Data Exchange (ETDEWEB)

    Nikkinen, M; Aarnio, P [Helsinki Univ. of Technology, Espoo (Finland); Honkamaa, T; Tiilikainen, H [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)

    1998-12-31

    The task of the team was to create a fallout map of {sup 137}Cs on a specified area in Padasjoki Auttoinen village. The team used AB-420 helicopter of the Finnish Frontier Guard. The team had two measuring systems: HPGe system (relative efficiency 18%) and NaI system (5`x5`). Both systems produced similar maps. The average {sup 137}Cs fallout within the area (lakes and ponds included) was 88 kBq m{sup -2,} the maximum value being 161 kBq m{sup -2}. In an emergency the HPGe is superior to NaI because of its better energy resolution, giving possibility to obtain nuclide-specific results. (au).

  4. Airborne fallout mapping of {sup 137}Cs Finnish defence forces team

    Energy Technology Data Exchange (ETDEWEB)

    Kettunen, M; Heininen, T [Finnish Defence Forces Research Centre, Lakiala (Finland); Pulakka, M [Finnish Air Force Depot, Tampere (Finland)

    1998-12-31

    The main task of the team was to create a fallout map of {sup 137}Cs in a specified area in Padasjoki Auttoinen village. The team used an MI-8 helicopter of the Finnish Air Force. The team had an HPGe system (relative efficiency 70%) to measure nuclide specific ground contamination level. For navigation the team took advantage of the DGPS service provided by Finnish Broadcasting company utilizing the RDS-channel to get position accuracy within 2 meters. The correction signal is reachable nationwide on the FM transmitter network. The system produced a distribution map for {sup 40}K and fallout maps for {sup 134,137}Cs using a Micro Station Program with TerraModeler application. The maximum measured {sup 137}Cs ground contamination exceeded 130-140 kBqm{sup -2}. (au).

  5. Warm Debris Disk Candidates from WISE

    Science.gov (United States)

    Padgett, Deborah; Stapelfeldt, Karl; Liu, Wilson; Leisawitz, David

    2011-01-01

    The Wide Field Infrared Survey Explorer (WISE) has just completed a sensitive all-sky survey in photometric bands at 3.4, 4.6, 12, and 22 microns. We report on a preliminary investigation of main sequence Hipparcos and Tycho catalog stars with 22 micron emission in excess of photospheric levels. This warm excess emission traces material in the circumstellar region likely to host terrestrial planets and is preferentially found in young systems with ages warm debris disk candidates are detected among FGK stars and 150 A stars within 120 pc. We are in the process of obtaining spectra to determine spectral types and activity level of these stars and are using HST, Herschel and Keck to characterize the dust, multiplicity, and substellar companions of these systems. In this contribution, we will discuss source selection methods and individual examples from among the WISE debris disk candidates.

  6. Rocky Planetary Debris Around Young WDs

    Science.gov (United States)

    Gaensicke, B.

    2014-04-01

    The vast majority of all known planet host stars, including the Sun, will eventually evolve into red giants and finally end their lives as white dwarfs: extremely dense Earth-sized stellar embers. Only close-in planets will be devoured during the red-giant phase. In the solar system, Mars, the asteroid belt, and all the giant planets will escape evaporation, and the same is true for many of the known exo-planets. It is hence certain that a significant fraction of the known white dwarfs were once host stars to planets, and it is very likely that many of them still have remnants of planetary systems. The detection of metals in the atmospheres of white dwarfs is the unmistakable signpost of such evolved planetary systems. The strong surface gravity of white dwarfs causes metals to sink out of the atmosphere on time-scales much shorter than their cooling ages, leading unavoidably to pristine H/He atmospheres. Therefore any metals detected in the atmosphere of a white dwarf imply recent or ongoing accretion of planetary debris. In fact, planetary debris is also detected as circumstellar dust and gas around a number of white dwarfs. These debris disks are formed from the tidal disruption of asteroids or Kuiper belt-like objects, stirred up by left-over planets, and are subsequently accreted onto the white dwarf, imprinting their abundance pattern into its atmosphere. Determining the photospheric abundances of debris-polluted white dwarfs is hence entirely analogue to the use of meteorites, "rocks that fell from the sky", for measuring the abundances of planetary material in the solar system. I will briefly review this new field of exo-planet science, and then focus on the results of a large, unbiased COS snapshot survey of relatively young ( 20-100Myr) white dwarfs that we carried out in Cycle 18/19. * At least 30% of all white dwarfs in our sample are accreting planetary debris, and that fraction may be as high as 50%. * In most cases where debris pollution is detected

  7. Debris Dispersion Model Using Java 3D

    Science.gov (United States)

    Thirumalainambi, Rajkumar; Bardina, Jorge

    2004-01-01

    This paper describes web based simulation of Shuttle launch operations and debris dispersion. Java 3D graphics provides geometric and visual content with suitable mathematical model and behaviors of Shuttle launch. Because the model is so heterogeneous and interrelated with various factors, 3D graphics combined with physical models provides mechanisms to understand the complexity of launch and range operations. The main focus in the modeling and simulation covers orbital dynamics and range safety. Range safety areas include destruct limit lines, telemetry and tracking and population risk near range. If there is an explosion of Shuttle during launch, debris dispersion is explained. The shuttle launch and range operations in this paper are discussed based on the operations from Kennedy Space Center, Florida, USA.

  8. Radionuclide characterization and associated dose from long-lived radionuclides in close-in fallout delivered to the marine environment at Bikini and Enewetak Atolls

    International Nuclear Information System (INIS)

    Robison, W.L.; Noshkin, V.E.

    1999-01-01

    Between June 1946 and October 1958, Enewetak and Bikini Atolls were used by the US as testing grounds for 66 nuclear devices. The combined explosive yield from these tests was 107 million t (million t TNT equivalents). This testing produced close-in fallout debris that was contaminated with quantities of radioactive fission and particle activated products, and unspent radioactive nuclear fuel that entered the aquatic environment of the atolls. Today, the sediments in the lagoons are reservoirs for tens of TBq of the transuranics and some long-lived fission and activation products. The larger amounts of contamination are associated with fine and coarse sediment material adjacent to the locations of the high yield explosions. Radionuclides are also distributed vertically in the sediment column to various depths in all regions of the lagoons. Concentrations greater than fallout background levels are found in filtered water sampled over several decades from all locations and depths in the lagoons. This is a direct indication that the radionuclides are continuously mobilized to solution from the solid phases. Of particular importance is the fact that the long-lived radionuclides are accumulated to different levels by indigenous aquatic plants and organisms that are used as food by resident people. One might anticipate finding continuous high contamination levels in many of the edible marine organisms from the lagoons, since the radionuclides associated with the sediments are not contained and are available to the different organisms in a relatively shallow water environment. This is not the case. We estimate that the radiological dose from consumption of the edible parts of marine foods at Enewetak and Bikini is presently approximately 0.05% of the total 50-year integral effective dose from all other exposure pathways that include ingestion of terrestrial foods and drinking water, external exposure and inhalation. The total radiological dose from the marine pathway is

  9. Radionuclide characterization and associated dose from long-lived radionuclides in close-in fallout delivered to the marine environment at Bikini and Enewetak Atoll

    International Nuclear Information System (INIS)

    Noshkin, V. E.; Robison, W. L.

    1998-01-01

    Between June 1946 and October 1958, Enewetak and Bikini Atolls were used by the United States as testing grounds for 66 nuclear devices. The combined explosive yield from these tests was 107 Mt (Mt TNT equivalents). This testing produced close-in fallout debris that was contaminated with quantities of radioactive fission and particle activated products, and unspent radioactive nuclear fuel that entered the aquatic environment of the atolls. Today, the sediments in the lagoons are reservoirs for 10's of TBq of the transuranics and some long-lived fission and activation products. The larger amounts of contamination are associated with fine and coarse sediment material adjacent to the locations of the high yield explosions. Radionuclides are also distributed vertically in the sediment column to various depths in all regions of the lagoons. Concentrations greater than fallout background levels are found in filtered water sampled over several decades from all locations and depths in the lagoons. This is a direct indication that the radionuclides are continuously mobilized to solution from the solid phases. Of particular importance is the fact that the long-lived radionuclides are accumulated to different levels by indigenous aquatic plants and organisms that are used as food by resident people. One might anticipate finding continuous high contamination levels in many of the edible marine organisms from the lagoons, since the radionuclides associated with the sediments are not contained and are available to the different organisms in a relatively shallow water environment. This is not the case. We estimate that the radiological dose from consumption of the edible parts of marine foods at Enewetak and Bikini is presently about 0.05% of the total 50-year integral effective dose from all other exposure pathways that include ingestion of terrestrial foods and drinking water, external exposure and inhalation. The total radiological dose from the marine pathway is dominated by

  10. Plastic debris in the open ocean

    OpenAIRE

    Cózar, Andrés; Echevarría, Fidel; González-Gordillo, J. Ignacio; Irigoien, Xabier; Úbeda, Bárbara; Hernández-León, Santiago; Palma, Álvaro T.; Navarro, Sandra; García-de-Lomas, Juan; Ruiz, Andrea; Fernández-de-Puelles, María L.; Duarte, Carlos M.

    2014-01-01

    There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density. Howeve...

  11. Optimized debris stoppers for Z-pinches

    Energy Technology Data Exchange (ETDEWEB)

    Gondarenko, N A; Pereira, N R [Berkeley Research Associates, Springfield, VA (United States)

    1997-12-31

    A pulse power generator discharging through an array of wires or a gas cylinder creates a pulse of useful soft x-rays, which is usually followed by deleterious byproducts such as plasma, hot gases and droplets of metal from evaporated electrodes. Separating the extraneous material from the x-rays is done with a debris shield. Optimization of such shields is discussed. (author). 3 figs., 3 refs.

  12. Orbital Debris: Past, Present, and Future

    Science.gov (United States)

    Stansbery, Gene; Johnson, Nicholas

    2013-01-01

    In the early days of spaceflight, the gBig Sky h theory was the near universally accepted paradigm for dealing with collisions of orbiting objects. This theory was also used during the early years of the aviation industry. Just as it did in aviation, the gBig Sky h theory breaks down as more and more objects accumulate in the environment. Fortunately, by the late 1970 fs some visionaries in NASA and the US Department of Defense (DoD) realized that trends in the orbital environment would inevitably lead to increased risks to operational spacecraft from collisions with other orbiting objects. The NASA Orbital Debris Program was established at and has been conducted at Johnson Space Center since 1979. At the start of 1979, fewer than 5000 objects were being tracked by the US Space Surveillance Network and very few attempts had been made to sample the environment for smaller sizes. Today, the number of tracked objects has quadrupled. Ground ]based and in situ measurements have statistically sampled the LEO environment over most sizes and mitigation guidelines and requirements are common among most space faring nations. NASA has been a leader, not only in defining the debris environment, but in promoting awareness of the issues in the US and internationally, and in providing leadership in developing policies to address the issue. This paper will discuss in broad terms the evolution of the NASA debris program from its beginnings to its present broad range of debris related research. The paper will discuss in some detail current research topics and will attempt to predict future research trends.

  13. The California Debris Commission: A History

    Science.gov (United States)

    1981-01-01

    the pipe a more freely in the horizontal plane, while vertical elastic packing in the joint instead of two stable instrument to handle. movement was...report of January duplicate and triplicate taxation , and (4) it 1880 painted a dark and sobering picture Following two months of intense and had not the...isolated cases it is possible to impound debris without injury; also, that loca- tions exist in the canons of the different mining streams in the Sierra

  14. Forewarning of Debris flows using Intelligent Geophones

    Science.gov (United States)

    PK, I.; Ramesh, M. V.

    2017-12-01

    Landslides are one of the major catastrophic disasters that cause significant damage to human life and civil structures. Heavy rainfall on landslide prone areas can lead to most dangerous debris flow, where the materials such as mud, sand, soil, rock, water and air will move with greater velocity down the mountain. This sudden slope instability can lead to loss of human life and infrastructure. According to our knowledge, till now no one could identify the minutest factors that lead to initiation of the landslide. In this work, we aim to study the landslide phenomena deeply, using the landslide laboratory set up in our university. This unique mechanical simulator for landslide initiation is equipped with the capability to generate rainfall, seepage, etc., in the laboratory setup. Using this setup, we aim to study several landslide initiation scenarios generated by varying different parameters. The complete setup will be equipped with heterogeneous sensors such as rain gauge, moisture sensor, pore pressure sensor, strain gauges, tiltmeter, inclinometer, extensometer, and geophones. Our work will focus on the signals received from the intelligent geophone system for identifying the underground vibrations during a debris flow. Using the large amount of signals derived from the laboratory set up, we have performed detailed signal processing and data analysis to determine the fore warning signals captured by these heterogeneous sensors. Detailed study of these heterogeneous signals has provided the insights to forewarning the community based on the signals generated during the laboratory tests. In this work we will describe the details of the design, development, methodology, results, inferences and the suggestion for the next step to detect and forewarn the students. The response of intelligent geophone sensors at the time of failure, failure style and subsequent debris flow for heterogeneous soil layers were studied, thus helping in the development of fore warning

  15. Estimates of probability of severe accidents at European reactors potentially leading to fallout in the UK

    International Nuclear Information System (INIS)

    Mottram, P.R.; Goldemund, M.H.

    2001-08-01

    This study has examined a large number of reactors and data for Nuclear Power Plants (NPPs) in Western Europe, Russia, the seven Central and Eastern European Countries (CEECs) seeking membership of the European Union, and the Newly Independent States (NIS) with operable NPPs. The potential threats from severe accidents at these NPPs causing fallout in the UK has been estimated using IAEA guidelines and Probabilistic Safety Assessments carried out in the specified countries. (author)

  16. Measurement of radioactive fallout in rainwater and air at remote areas (1995-96)

    International Nuclear Information System (INIS)

    U Wai Zin Oo; Daw War War Myo Aung; U Khin Maung Latt; U Maung Maung Tin

    2001-01-01

    Radioactive fallout in rainwater and air collected from Yangon Division (Ahlone, Yangon), Pago Division (Pago and Thanut Pin), Mandalay Division (Pyinoolwin, Mandalay and Meikhtilar), Mon State (Mawlamyine, Kyaikame, Beelin, Taungzun, Kyaikhto, Kinpunsakan and Thayetkone village), and Shan State (Larsoh) were measured by using low level Beta Counting System. It was found that the radioactivities were less than the maximum permissible level recommended by the International Commission on Radiological Production. (author)

  17. Some perspectives on action levels in areas contaminated with radioactive fallout

    Energy Technology Data Exchange (ETDEWEB)

    Walinder, Gunnar

    1986-07-01

    Maximum permissible radiation levels for planned activities must be distinguished from action levels as applied to protect people and animals after nuclear accidents. The essential thing with action levels is the optimal balance between the danger of the radiation and the harm involved in the counter measures themselves. Among other things these counter measures are dependent on the magnitude of the fallout, i.e. on the apprehended doses to man and animals.

  18. Radioactive contamination: atlas France and Europe. French soils contamination by Chernobyl accident fallouts - The lie evidences

    International Nuclear Information System (INIS)

    Paris, Andre; Castanier, Corinne

    2002-01-01

    This document deals with the Chernobyl nuclear accident impacts and the authorities transparency. The first part is a reference document constituted by the CRIIRAD and showing how the authorities strove for minimizing the real contamination of French soils by the Chernobyl fallouts. In the second part, an atlas provides the detailed maps of the radioactive contamination of soils based on more than 3000 measurements carried out by a geologist, Andre Paris, assisted by the CRIIRAD laboratory

  19. Some perspectives on action levels in areas contaminated with radioactive fallout

    International Nuclear Information System (INIS)

    Walinder, Gunnar

    1986-01-01

    Maximum permissible radiation levels for planned activities must be distinguished from action levels as applied to protect people and animals after nuclear accidents. The essential thing with action levels is the optimal balance between the danger of the radiation and the harm involved in the counter measures themselves. Among other things these counter measures are dependent on the magnitude of the fallout, i.e. on the apprehended doses to man and animals

  20. Distribution of dose rates due to fallout from the Fukushima Daiichi reactor accident

    International Nuclear Information System (INIS)

    Minato, Susumu

    2011-01-01

    A number of dose rate data taken after the Fukushima Daiichi reactor accident occurred have been collected through official websites of prefectural governments. Subtracting natural background dose rates from these data, contributions due to fallout alone were evaluated. A train-borne survey was carried out to verify the accuracy of the contour map. The dose rate variation pattern obtained by the survey coincided fairly well with that of the map. (author)

  1. Transfer of fallout radionuclides by Fukushima NPP accident from tree crown to forest ecosystem

    Science.gov (United States)

    Onda, Y.; Kato, H.; Wakahara, T.; Kawamori, A.; Tsujimura, M.

    2011-12-01

    Radioactive contamination has been detected in Fukushima and the neighboring prefectures due to the nuclear accident at Fukushima Daiichi Nuclear Power Plant (NPP) following the earthquake and tsunami on 11 March 2011. The total deposition of radioactive materials in fallout samples for 137Cs ranged from 0.02to >10 M Bq/m2 for Cs-137. Experimental catchments have been established in Yamakiya district, Kawamata Town, Fukushima prefecture, located about 35 km from Fukushima power plant, and designated as the evacuated zone. Approximate Cs-137 fallout in this area is 200-600k Bq/m2. We established 3 forest sites: broad leaf tree forest and two Japanese cedar forest plantation (young and mature). In each site we installed towers of 8-12 meters. Using these towers, we sampled tree leaves, and measure Cs-137 and Cs-134 in the laboratory, and also we have measure Cs-137, Cs-134 content at various height in each forest using a portable High Purity Germanium (HPGe) detector (Ortech; Detective-EX). We also measured the throughfall, stem flow and litter fall inside of the forest. In each site, we establish the 20 m x 20 m plot to monitor the changes of fallout radionuclides through time with the portable HPGe detector. The monitoring is now ongoing but we found significant amount of Cs-134 and Cs-137 has been trapped by cedar forest plantations especially young trees, but not so much in broad leaf trees. The trapped Cs-137 and Cs-134 is then washed by rainfall and found into throughfall. Therefore, in forest ecosystems, the fallout has been still ongoing, and and effective remediation method in forested area (especially cedar plantation) can be removing the trees.

  2. Twenty-year review of medical findings in a Marshallese population accidentally exposed to radioactive fallout

    International Nuclear Information System (INIS)

    Conard, R.A.

    1975-01-01

    A summary is presented of results of medical examinations of inhabitants of the Marshall Islands during the 20-year period following the exposure of Rongelap people to radioactive fallout in 1954. The initial effect observed was β burns of the skin of some individuals. Few significant findings were observed during the subsequent 9-year period, although an increase in miscarriages and stillbirths among the exposed women was noted. In 1963 some thyroid abnormalities and growth retardation of some children were noted. (177 references)

  3. The corkscrew sperm defect in Danish bulls - a possible indicator of nuclear fallout

    International Nuclear Information System (INIS)

    Blom, Erik

    1978-01-01

    In spite of the fact that the sterilizing corkscrew sperm defect was described about 20 years ago, very little is as yet known about a possible causal factor and about the genesis of the defect. Up to now 60 Danish cases have been recorded showing no proof whatsoever of heredity. The cases have predominantly been found in older bulls of the Red Danish breed and during a period with a rather high degree of atmospheric pollution from nuclear fallout. (author)

  4. Immunological effects of low dose radiation. Absent or minor effects of Chernobyl fallout in Norway?

    International Nuclear Information System (INIS)

    Reitan, J.B.; Bergan, T.D.; Strand, P.; Melbye, O.J.

    1998-01-01

    In this pilot study of those Norwegian individuals most heavily exposed to the Chernobyl Fallout, immunological parameters generally stayed within normal limits. However, some parameter, apparently within the assumed normal range did, in fact correlate to the estimated individual dose as assessed by wholebody counting of radiocaesium content. The small possible effects revealed in this study may represent real biological effects, but do not necessarily represent a health detriment. 43 refs., 4 figs., 6 tabs

  5. HASL measurements of fallout following the September 26, 1976 Chinese nuclear test

    International Nuclear Information System (INIS)

    1976-10-01

    Results are reported from measurements of radioactivity in the fallout from the nuclear test conducted by the Peoples Republic of China on September 26th, 1976. These measurements were carried on through Monday, October 18th. Results of these measurements made in New York and New Jersey, including external radiation exposure, air concentrations, deposition and the concentration of radioiodine in milk, are reported. An estimate of the thyroid dose from milk consumption is also included

  6. The health after effects on children exposed to Chernobyl radiation fallout

    International Nuclear Information System (INIS)

    Contis, G.

    2002-01-01

    The purpose of this paper is to describe some of the long-term health consequences that are now being detected in Ukrainian adolescents who, as children, were exposed to Chornobyl radiation fallout fifteen years ago. The information presented will emphasize the importance of ensuring that nuclear power plants are built and operated with all the safeguards needed to prevent a recurrence of the Chornobyl disaster

  7. Long-range volcanic ash transport and fallout during the 2008 eruption of Chaiten volcano, Chile

    Science.gov (United States)

    Durant, A. J.; Prata, A. J.; Villarosa, G.; Rose, W. I.; Delmelle, P.; Viramonte, J.

    2012-04-01

    The May 2008 eruption of Chaitén volcano, Chile, provided a rare opportunity to measure the long-range transport of volcanic emissions and characteristics of a widely-dispersed terrestrial ash deposit. Airborne ash mass, quantified using thermal infrared satellite remote sensing, ranged between 0.2-0.4 Tg during the period 3-7 May 2008. A high level of spatiotemporal correspondence was observed between cloud trajectories and changes in surface reflectivity, which was inferred to indicate ash deposition. The evolution of the deposit was mapped for the first time using satellite-based observations of surface reflectivity. The distal (>80 km) ash deposit was poorly sorted and fine grained, and mean particle size varied very little beyond a distance >300 km. There were 3 consistent particle size subpopulations in fallout at distances >300 km which suggests that aggregation influenced particle settling. Discrete temporal sampling and characterisation of fallout demonstrated contributions from specific eruptive phases. Some evidence for winnowing was identified through comparison of samples collected at the time of deposition to bulk samples collected months after deposition. X-Ray Photoelectron Spectroscopy (XPS) analyses revealed surface enrichments in Ca, Na and Fe and the presence of coatings of mixed Ca-, Na- and Fe-rich salts on ash particles prior to deposition. XPS analyses revealed strong surface Fe enrichments (in contrast to the results from bulk leachate analyses), which indicates that surface analysis techniques should be applied to investigate potential influences on ocean productivity in response to volcanic ash fallout over oceans. Low S:Cl ratios in leachates indicate that the eruption had a low S content, and high Cl:F ratios imply gas-ash interaction within a Cl-rich environment. We estimate that ash fallout had potential to scavenge ~42 % of total S released into the atmosphere prior to deposition.

  8. Immunological effects of low dose radiation. Absent or minor effects of Chernobyl fallout in Norway?

    Energy Technology Data Exchange (ETDEWEB)

    Reitan, J.B.; Bergan, T.D.; Strand, P. [Statens Straalevern, Oesteraas (Norway); Melbye, O.J. [Rikshospitalet, Oslo (Norway)

    1998-01-01

    In this pilot study of those Norwegian individuals most heavily exposed to the Chernobyl Fallout, immunological parameters generally stayed within normal limits. However, some parameter, apparently within the assumed normal range did, in fact correlate to the estimated individual dose as assessed by wholebody counting of radiocaesium content. The small possible effects revealed in this study may represent real biological effects, but do not necessarily represent a health detriment. 43 refs., 4 figs., 6 tabs.

  9. Debris flow-induced topographic changes: effects of recurrent debris flow initiation.

    Science.gov (United States)

    Chen, Chien-Yuan; Wang, Qun

    2017-08-12

    Chushui Creek in Shengmu Village, Nantou County, Taiwan, was analyzed for recurrent debris flow using numerical modeling and geographic information system (GIS) spatial analysis. The two-dimensional water flood and mudflow simulation program FLO-2D were used to simulate debris flow induced by rainfall during typhoon Herb in 1996 and Mindulle in 2004. Changes in topographic characteristics after the debris flows were simulated for the initiation of hydrological characteristics, magnitude, and affected area. Changes in topographic characteristics included those in elevation, slope, aspect, stream power index (SPI), topographic wetness index (TWI), and hypsometric curve integral (HI), all of which were analyzed using GIS spatial analysis. The results show that the SPI and peak discharge in the basin increased after a recurrence of debris flow. The TWI was higher in 2003 than in 2004 and indicated higher potential of landslide initiation when the slope of the basin was steeper. The HI revealed that the basin was in its mature stage and was shifting toward the old stage. Numerical simulation demonstrated that the parameters' mean depth, maximum depth, affected area, mean flow rate, maximum flow rate, and peak flow discharge were increased after recurrent debris flow, and peak discharge occurred quickly.

  10. Controlling the Growth of Future LEO Debris Populations with Active Debris Removal

    Science.gov (United States)

    Liou, J.-C.; Johnson, N. L.; Hill, N. M.

    2008-01-01

    Active debris removal (ADR) was suggested as a potential means to remediate the low Earth orbit (LEO) debris environment as early as the 1980s. The reasons ADR has not become practical are due to its technical difficulties and the high cost associated with the approach. However, as the LEO debris populations continue to increase, ADR may be the only option to preserve the near-Earth environment for future generations. An initial study was completed in 2007 to demonstrate that a simple ADR target selection criterion could be developed to reduce the future debris population growth. The present paper summarizes a comprehensive study based on more realistic simulation scenarios, including fragments generated from the 2007 Fengyun-1C event, mitigation measures, and other target selection options. The simulations were based on the NASA long-term orbital debris projection model, LEGEND. A scenario, where at the end of mission lifetimes, spacecraft and upper stages were moved to 25-year decay orbits, was adopted as the baseline environment for comparison. Different annual removal rates and different ADR target selection criteria were tested, and the resulting 200-year future environment projections were compared with the baseline scenario. Results of this parametric study indicate that (1) an effective removal strategy can be developed based on the mass and collision probability of each object as the selection criterion, and (2) the LEO environment can be stabilized in the next 200 years with an ADR removal rate of five objects per year.

  11. Mitigation of Debris Flow Damage--­ A Case Study of Debris Flow Damage

    Science.gov (United States)

    Lin, J. C.; Jen, C. H.

    Typhoon Toraji caused more than 30 casualties in Central Taiwan on the 31st July 2001. It was the biggest Typhoon since the Chi-Chi earthquake of 1999 with huge amounts of rainfall. Because of the influence of the earthquake, loose debris falls and flows became major hazards in Central Taiwan. Analysis of rainfall data and sites of slope failure show that damage from these natural hazards were enhanced as a result of the Chi-Chi earthquake. Three main types of hazard occurred in Central Taiwan: land- slides, debris flows and gully erosion. Landslides occurred mainly along hill slopes and banks of channels. Many dams and houses were destroyed by flooding. Debris flows occurred during typhoon periods and re-activated ancient debris depositions. Many new gullies were therefore developed from deposits loosened and shaken by the earthquake. This paper demonstrates the geological/geomorphological background of the hazard area, and reviews methods of damage mitigation in central Taiwan. A good example is Hsi-Tou, which had experienced no gully erosion for more than 40 years. The area experienced much gully erosion as a result of the combined effects of earth- quake and typhoon. Although Typhoon Toraji produced only 30% of the rainfall of Typhoon Herb of 1996, it caused more damage in the Hsi-Tou area. The mitigation of debris flow hazards in Hsi-tou area is discussed in this paper.

  12. Plastic debris in the open ocean

    KAUST Repository

    Cozar, Andres

    2014-06-30

    There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density. However, the global load of plastic on the open ocean surface was estimated to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to determine the nature and significance of the impacts of plastic pollution in the ocean.

  13. CIRCUMSTELLAR DEBRIS DISKS: DIAGNOSING THE UNSEEN PERTURBER

    Energy Technology Data Exchange (ETDEWEB)

    Nesvold, Erika R. [Department of Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Rd., Washington, DC 20015 (United States); Naoz, Smadar; Vican, Laura [Department of Physics and Astronomy, UCLA, 475 Portola Plaza, Los Angeles, CA 90095 (United States); Farr, Will M. [School of Physics and Astronomy, University of Birmingham, Birmingham, B15 2TT (United Kingdom)

    2016-07-20

    The first indication of the presence of a circumstellar debris disk is usually the detection of excess infrared emission from the population of small dust grains orbiting the star. This dust is short-lived, requiring continual replenishment, and indicating that the disk must be excited by an unseen perturber. Previous theoretical studies have demonstrated that an eccentric planet orbiting interior to the disk will stir the larger bodies in the belt and produce dust via interparticle collisions. However, motivated by recent observations, we explore another possible mechanism for heating a debris disk: a stellar-mass perturber orbiting exterior to and inclined to the disk and exciting the disk particles’ eccentricities and inclinations via the Kozai–Lidov mechanism. We explore the consequences of an exterior perturber on the evolution of a debris disk using secular analysis and collisional N -body simulations. We demonstrate that a Kozai–Lidov excited disk can generate a dust disk via collisions and we compare the results of the Kozai–Lidov excited disk with a simulated disk perturbed by an interior eccentric planet. Finally, we propose two observational tests of a dust disk that can distinguish whether the dust was produced by an exterior brown dwarf or stellar companion or an interior eccentric planet.

  14. Plastic debris in the open ocean.

    Science.gov (United States)

    Cózar, Andrés; Echevarría, Fidel; González-Gordillo, J Ignacio; Irigoien, Xabier; Ubeda, Bárbara; Hernández-León, Santiago; Palma, Alvaro T; Navarro, Sandra; García-de-Lomas, Juan; Ruiz, Andrea; Fernández-de-Puelles, María L; Duarte, Carlos M

    2014-07-15

    There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density. However, the global load of plastic on the open ocean surface was estimated to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to determine the nature and significance of the impacts of plastic pollution in the ocean.

  15. Bremsstrahlung converter debris shields: test and analysis

    International Nuclear Information System (INIS)

    Reedy, E.D. Jr.; Perry, F.C.

    1983-10-01

    Electron beam accelerators are commonly used to create bremsstrahlung x-rays for effects testing. Typically, the incident electron beam strikes a sandwich of three materials: (1) a conversion foil, (2) an electron scavenger, and (3) a debris shield. Several laboratories, including Sandia National Laboratories, are developing bremsstrahlung x-ray sources with much larger test areas (approx. 200 to 500 cm 2 ) than ever used before. Accordingly, the debris shield will be much larger than before and subject to loads which could cause shield failure. To prepare for this eventuality, a series of tests were run on the Naval Surface Weapons Center's Casino electron beam accelerator (approx. 1 MeV electrons, 100 ns FWHM pulse, 45 kJ beam energy). The primary goal of these tests was to measure the stress pulse which loads a debris shield. These measurements were made with carbon gages mounted on the back of the converter sandwich. At an electron beam fluence of about 1 kJ/cm 2 , the measured peak compressive stress was typically in the 1 to 2 kbar range. Measured peak compressive stress scaled in a roughly linear manner with fluence level as the fluence level was increased to 10 kJ/cm 2 . The duration of the compressive pulse was on the order of microseconds. In addition to the stress wave measurements, a limited number of tests were made to investigate the type of damage generated in several potential shield materials

  16. Plastic debris in the open ocean

    Science.gov (United States)

    Cózar, Andrés; Echevarría, Fidel; González-Gordillo, J. Ignacio; Irigoien, Xabier; Úbeda, Bárbara; Hernández-León, Santiago; Palma, Álvaro T.; Navarro, Sandra; García-de-Lomas, Juan; Ruiz, Andrea; Fernández-de-Puelles, María L.; Duarte, Carlos M.

    2014-01-01

    There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density. However, the global load of plastic on the open ocean surface was estimated to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to determine the nature and significance of the impacts of plastic pollution in the ocean. PMID:24982135

  17. Relative effectiveness of structures as protection from gamma radiation from cloud and fallout sources as a function of source energy

    International Nuclear Information System (INIS)

    Fingerlos, J.P.

    1984-01-01

    In the event of a release of radioactive material, it is necessary to know the doses the public could receive in order to make decisions that minimize the public's risk. In order to determine what doses the public might receive if they try to evacuate or seek shelter, it is necessary to know how much protection structures such as homes and vehicles provide. This information is well known only for a few gamma ray spectra, such as that from weapon fallout. The research reported here transfers the knowledge gained from the previous weapon-fallout shielding work to realistic protection factors for possible accidental releases whatever the released spectrum might be. Point kernel models were developed for both the fallout and cloud sources. That development included a method of accurately combining buildup factors in multi-region problems over wide ranges of energy and photon mean free path. A generalized method for calculating the effect of ground roughness on the attentuation factor for fallout sources was also developed. The results were reported for the 1-hr weapon fallout, and TMI-2 cloud and fallout spectra, as well as for discrete energies from 15 KeV to 15 MeV. The structures given as examples include small wood frame and large brick houses

  18. Concentrations of /sup 90/Sr and /sup 137/Cs rain and dry fallout, milk and service water in Aichi Prefecture

    Energy Technology Data Exchange (ETDEWEB)

    Ohnuma, Shoko; Kondou, Fumio; Chaya, Kunio (Aichi Prefectural Inst. of Public Health, Nagoya (Japan))

    1989-03-01

    The investigation by radioactivation analysis was carried out on the Sr-90 and Cs-137 concentrations in fallout, milk and source water and tap water from 1977 to 1987. The variation of the monthly and yearly amounts of Sr-90 and Cs-137 fallouts agreed well, and those have decreased for the last 11 years though affected by the nuclear experiments in China. The effect of the Chernobyl-4 accident on April 26, 1986 appeared conspicuously in the Cs-137 fallout, and the monthly fallout in May, 1986 was 3.50 mCi/km/sup 2/. As to the Sr-90 and Cs-137 concentrations in milk and service water, only the Cs-137 concentration in milk was correlated with the course for years before the Chernobyl-4 accident. The effect of the Chernobyl-4 accident was conspicuous in the Cs-137 concentration similarly to the case of fallout. In this case, in the measurement of service water after a half year, the data returned to the normal value, but in the case of milk, the decrease was slow. The method of investigation, the monthly and yearly fallout of Sr-90 and Cs-137, the Sr-90 and Cs-137 concentrations in milk and service water are reported. (K.I.).

  19. Local area distribution of fallout radionuclides from Fukushima Daiichi Nuclear Power Plant determined by autoradiography analysis

    International Nuclear Information System (INIS)

    Sakamoto, Fuminori; Ohnuki, Toshihiko; Kozai, Naofumi; Igarashi, Shosuke; Yamasaki, Shinya; Yoshida, Zenko; Tanaka, Shunichi

    2012-01-01

    The environmental behavior of radioactive Cs in the fallout from the accident of the Fukushima Daiichi Nuclear Power Plant has been studied by measuring its spatial distribution on/in trees, plants, and surface soil beneath the plants using autoradiography analysis. The results of autoradiography analysis showed that radioactive Cs was distributed on the branches and leaves of trees that were present during the accident and that only a small fraction of radioactive Cs was transported to new branches and leaves grown after the accident. Radioactive Cs was present on the grass and rice stubble on the soils, but not in the soils beneath the grass and rice stubble, indicating that the radioactive Cs was deposited on the grass and the rice plant. In addition, the ratio of the radioactive Cs that penetrated into the soil layer by weathering was very small two months after the accident. These results indicate that trees and other plants are the reservoir of the fallout Cs and function to retard the fallout Cs migration with rain water. (author)

  20. Mapping of caesium fallout from the Chernobyl accident in the Jotunheimen area

    International Nuclear Information System (INIS)

    Baranwal, Vikas C.; Ofstad, Frode; Roenning, Jan S.; Watson, Robin J.

    2011-01-01

    As a consequence of the Chernobyl accident, several areas in Norway received radioactive fallout. One of these areas is the eastern part of Jotunheimen in central Norway. Immediately after the accident in 1986, the Geological Survey of Norway (NGU) performed airborne gamma-ray spectroscopy in central Norway. At that time, it was not possible to calculate reliable radionuclide concentrations, and the data were presented as total counts per second. Several man-made radionuclides were present in the initial fallout, but due to short half-lives, most of these have now disintegrated into stable isotopes. 137Cs, with a half-life of 11.000 days (∼ 30 years) is still present in the environment in significant quantities, leading to high radioactivity levels in meat from reindeer and sheep. To obtain a detailed map of the caesium fallout concentration in Jotunheimen, an airborne gamma-ray spectrometry (AGRS) survey was carried out, focusing on reindeer grazing areas. This project was a cooperation between Reindeer Husbandry Administration, Norwegian Radiation Protection Authority and the Geological Survey of Norway.(Au)

  1. Synthetic fibers in atmospheric fallout: A source of microplastics in the environment?

    Science.gov (United States)

    Dris, Rachid; Gasperi, Johnny; Saad, Mohamed; Mirande, Cécile; Tassin, Bruno

    2016-03-15

    Sources, pathways and reservoirs of microplastics, plastic particles smaller than 5mm, remain poorly documented in an urban context. While some studies pointed out wastewater treatment plants as a potential pathway of microplastics, none have focused on the atmospheric compartment. In this work, the atmospheric fallout of microplastics was investigated in two different urban and sub-urban sites. Microplastics were collected continuously with a stainless steel funnel. Samples were then filtered and observed with a stereomicroscope. Fibers accounted for almost all the microplastics collected. An atmospheric fallout between 2 and 355 particles/m(2)/day was highlighted. Registered fluxes were systematically higher at the urban than at the sub-urban site. Chemical characterization allowed to estimate at 29% the proportion of these fibers being all synthetic (made with petrochemicals), or a mixture of natural and synthetic material. Extrapolation using weight and volume estimates of the collected fibers, allowed a rough estimation showing that between 3 and 10 tons of fibers are deposited by atmospheric fallout at the scale of the Parisian agglomeration every year (2500 km(2)). These results could serve the scientific community working on the different sources of microplastic in both continental and marine environments. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Concentration of 7Be in the lower atmosphere and fallout rate in Tokai

    International Nuclear Information System (INIS)

    Amano, Hikaru; Kasai, Atsushi

    1981-01-01

    Beryllium-7, cosmic ray produced radioactivity, its monthly average concentration in the lower atmosphere and monthly fallout rate were measured in Tokai, Japan. Then, the monthly variations were compared with those of fission products due to nuclear detonations in the atmosphere. The concentration of 7 Be in the lower atmosphere ranged from 0.5 x 10 -1 pCi/m 3 to 2.5 x 10 -1 pCi/m 3 in Tokai between the observed period, 1975 - 1977. The fallout rate of 7 Be vibrated widely, its range was from the detection limits to 1.2 x 10 4 pCi/m 2 . The monthly variations were not always the same with variations of the fission products. Fallout rate of 7 Be depended on the rain strongly. The concentration of 7 Be in the rain was measured, too. Then the range was from 9.2 pCi/l to 1.9 x 10 2 pCi/l between the observed period 1976.9 - 1977.2. (author)

  3. Childhood leukaemia in Great Britain and fallout from nuclear weapons testing

    International Nuclear Information System (INIS)

    Haynes, R.; Bentham, G.

    1995-01-01

    The possible effects of radiation from fallout on childhood leukaemia mortality from 1950 to 1987 and registrations from 1963 to 1987 were assessed using a division of Great Britain into regions with higher rainfall and a consequently higher fallout radiation dose in the 1960s and regions with lower rainfall and a lower radiation dose. Childhood leukaemia mortality rates declined and registration rates increased throughout the period. For ages 0-14 years, the differences between rates in wet regions and dry regions were small and appeared unrelated to periods of low, medium and high radiation exposure based on dose equivalent to the red bone marrow after birth. For the 0-4 years age group the highest ratios of leukaemia death rates and registration rates in the wet compared with the dry part of Great Britain occurred in the period of highest radiation exposure after birth. The death rate ratio was significantly raised in the period of high exposure compared with the surrounding medium exposure periods, but the difference in registration rate ratios between the high exposure period and the medium exposure period following was not statistically significant. The results might be explained by survival and registration changes, or chance in the case of registrations, but do not exclude the possibility that low doses of radiation from fallout were responsible for an increased risk of leukaemia in young children in Great Britain. (author)

  4. Latitudinal distribution of cesium-137 fallout in 1990 on Saxifraga oppositofolia from Ellesmere Island, Canada

    International Nuclear Information System (INIS)

    France, R.L.; Svoboda, J.; Taylor, H.W.

    1993-01-01

    During the first ski traverse of Ellesmere Island in spring 1990, purple saxifrage (Saxifraga oppositifolia) was collected at 10 sites from 76 to 82 degrees N. Measured 137 Cs levels in this cushion plant displayed a progressive decrease in activity north of 78 degrees, reflecting past global patterns of radionuclide fallout. Lower 137 Cs activity at the southern end of Ellesmere Island may reflect a northward shift of the distribution maximum since a previous latitudinal survey conducted in 1979-1980. Levels of 137 in three species of lichen were consistently higher than those for nearby saxifrage, possibly owing to the larger exposure to fallout for much of the year and the slower rate of lichen growth. In support of previous research, no 134 Cs was detected, which indicated that Chernobyl fallout had not been deposited in significant quantities at these extreme northern latitudes. Specific activities in 1990 of saxifrage samples were compared with similar samples collected during 1979-1980 to derive an effective half-life of 6.2 ± 1.0 years for northern Ellesmere Island

  5. Development and validation of a new fallout transport method using variable spectral winds

    International Nuclear Information System (INIS)

    Hopkins, A.T.

    1984-01-01

    A new method was developed to incorporate variable winds into fallout transport calculations. The method uses spectral coefficients derived by the National Meteorological Center. Wind vector components are computed with the coefficients along the trajectories of falling particles. Spectral winds are used in the two-step method to compute dose rate on the ground, downwind of a nuclear cloud. First, the hotline is located by computing trajectories of particles from an initial, stabilized cloud, through spectral winds to the ground. The connection of particle landing points is the hotline. Second, dose rate on and around the hotline is computed by analytically smearing the falling cloud's activity along the ground. The feasibility of using spectral winds for fallout particle transport was validated by computing Mount St. Helens ashfall locations and comparing calculations to fallout data. In addition, an ashfall equation was derived for computing volcanic ash mass/area on the ground. Ashfall data and the ashfall equation were used to back-calculate an aggregated particle size distribution for the Mount St. Helens eruption cloud

  6. Fallout exposure and thyroid diseases prevalence in the Semipalatinsk region of Kazakhstan

    International Nuclear Information System (INIS)

    Zhumadilov, Z.S.; Bhattarcharjee, Deborshi; Abisheva, G.

    2004-01-01

    The thyroid gland is considered to be especially susceptible to nuclear fallout because radioactive isotopes of iodine, and 131 I in particular, are major components of the fallout. During the 40 year period from 1949 to 1989, at Semipalatinsk Nuclear Test Site (SNTS) near the Semipalatinsk city, 30 surface, 88 atmospheric and 340 underground explosions of nuclear and thermonuclear devices were conducted by the former Soviet Union. The radionuclides emanating from these tests resulted in atmospheric and environmental contamination in the region of Semipalatinsk and parts of region of north-eastern Kazakhstan leading to various levels of acute and chronic radiation exposure. The radiation dosimetry results revealed that external dose to the population around Semipalatinsk due to radioactive cloud and fallout from the SNTS ranged from 35cGy-100cGy. The possible relationships between radiation exposure and the prevalence of thyroid gland abnormalities around the Semipalatinsk nuclear test site area are not well established and hence a detailed study of the same is suggested

  7. Mapping of caesium fallout from the Chernobyl accident in the Jotunheimen area

    Energy Technology Data Exchange (ETDEWEB)

    Baranwal, Vikas C.; Ofstad, Frode; Roenning, Jan S.; Watson, Robin J.

    2011-07-01

    As a consequence of the Chernobyl accident, several areas in Norway received radioactive fallout. One of these areas is the eastern part of Jotunheimen in central Norway. Immediately after the accident in 1986, the Geological Survey of Norway (NGU) performed airborne gamma-ray spectroscopy in central Norway. At that time, it was not possible to calculate reliable radionuclide concentrations, and the data were presented as total counts per second. Several man-made radionuclides were present in the initial fallout, but due to short half-lives, most of these have now disintegrated into stable isotopes. 137Cs, with a half-life of 11.000 days ({approx} 30 years) is still present in the environment in significant quantities, leading to high radioactivity levels in meat from reindeer and sheep. To obtain a detailed map of the caesium fallout concentration in Jotunheimen, an airborne gamma-ray spectrometry (AGRS) survey was carried out, focussing on reindeer grazing areas. This project was a cooperation between Reindeer Husbandry Administration, Norwegian Radiation Protection Authority and the Geological Survey of Norway. (auth)

  8. Treatment technology analysis for mixed waste containers and debris

    International Nuclear Information System (INIS)

    Gehrke, R.J.; Brown, C.H.; Langton, C.A.; Askew, N.M.; Kan, T.; Schwinkendorf, W.E.

    1994-03-01

    A team was assembled to develop technology needs and strategies for treatment of mixed waste debris and empty containers in the Department of Energy (DOE) complex, and to determine the advantages and disadvantages of applying the Debris and Empty Container Rules to these wastes. These rules issued by the Environmental Protection Agency (EPA) apply only to the hazardous component of mixed debris. Hazardous debris that is subjected to regulations under the Atomic Energy Act because of its radioactivity (i.e., mixed debris) is also subject to the debris treatment standards. The issue of treating debris per the Resource Conservation and Recovery Act (RCRA) at the same time or in conjunction with decontamination of the radioactive contamination was also addressed. Resolution of this issue requires policy development by DOE Headquarters of de minimis concentrations for radioactivity and release of material to Subtitle D landfills or into the commercial sector. The task team recommends that, since alternate treatment technologies (for the hazardous component) are Best Demonstrated Available Technology (BDAT): (1) funding should focus on demonstration, testing, and evaluation of BDAT on mixed debris, (2) funding should also consider verification of alternative treatments for the decontamination of radioactive debris, and (3) DOE should establish criteria for the recycle/reuse or disposal of treated and decontaminated mixed debris as municipal waste

  9. Debris flows associated with the 2015 Gorkha Earthquake in Nepal

    Science.gov (United States)

    Dahlquist, M. P.; West, A. J.; Martinez, J.

    2017-12-01

    Debris flows are a primary driver of erosion and a major geologic hazard in many steep landscapes, particularly near the headwaters of rivers, and are generated in large numbers by extreme events. The 2015 Mw 7.8 Gorkha Earthquake triggered 25,000 coseismic landslides in central Nepal. During the ensuing monsoon, sediment delivered to channels by landslides was mobilized in the heavy rains, and new postseismic landslides were triggered in rock weakened by the shaking. These coseismic and postseismic landslide-generated debris flows form a useful dataset for studying the impact and behavior of debris flows on one of the most active landscapes on Earth. Debris flow-dominated channel reaches are generally understood to have a topographic signature recognizable in slope-area plots and distinct from fluvial channels, but in examining debris flows associated with the Gorkha earthquake we find they frequently extend into reaches with geometry typically associated with fluvial systems. We examine a dataset of these debris flows, considering whether they are generated by coseismic or postseismic landslides, whether they are likely to be driving active incision into bedrock, and whether their channels correspond with those typically associated with debris flows. Preliminary analysis of debris flow channels in Nepal suggests there may be systematic differences in the geometry of channels containing debris flows triggered by coseismic versus postseismic landslides, which potentially holds implications for hazard analyses and the mechanics behind the different debris flow types.

  10. The effect of debris-flow composition on runout distance

    Science.gov (United States)

    de Haas, Tjalling; Braat, Lisanne; Leuven, Jasper; Lokhorst, Ivar; Kleinhans, Maarten

    2015-04-01

    Estimating runout distance is of major importance for the assessment and mitigation of debris-flow hazards. Debris-flow runout distance depends on debris-flow composition and topography, but state-of-the-art runout prediction methods are mainly based on topographical parameters and debris-flow volume, while composition is generally neglected or incorporated in empirical constants. Here we experimentally investigated the effect of debris-flow composition and topography on runout distance. We created the first small-scale experimental debris flows with self-formed levees, distinct lobes and morphology and texture accurately resembling natural debris flows. In general, the effect of debris-flow composition on runout distance was larger than the effect of topography. Enhancing channel slope and width, outflow plain slope, debris-flow size and water fraction leads to an increase in runout distance. However, runout distance shows an optimum relation with coarse-material and clay fraction. An increase in coarse-material fraction leads to larger runout distances by increased grain collisional forces and more effective levee formation, but too much coarse debris causes a large accumulation of coarse debris at the flow front, enhancing friction and decreasing runout. An increase in clay fraction initially enlarges the volume and viscosity of the interstitial fluid, liquefying the flow and enhancing runout, while a further increase leads to very viscous flows with high yield strength, reducing runout. These results highlight the importance and further need of research on the relation between debris-flow composition and runout distance. Our experiments further provide valuable insight on the effects of debris-flow composition on depositional mechanisms and deposit morphology.

  11. Glaciation of alpine valleys: The glacier - debris-covered glacier - rock glacier continuum

    Science.gov (United States)

    Anderson, Robert S.; Anderson, Leif S.; Armstrong, William H.; Rossi, Matthew W.; Crump, Sarah E.

    2018-06-01

    because they are most common on lee sides of ridges and peaks where wind-blown snow enhances the strength of the avalanche source. To maintain positive mass balance, the avalanche cone developed in the winter must be sufficiently thick not to melt entirely in the summer, thus providing an ice accumulation area for the rock glacier. In the absence of rockfall, this would support a short cirque glacier. The presence of debris, however, facilitates the development of rock glaciers with lengths of hundreds of meters, thicknesses of tens of meters, and speeds of meters per year that are well described by numerical models. Numerical models are used to explore the alpine glacier response to its climate history. In warming climates, a debris-covered glacier can transform into a much shorter rock glacier, leaving in its wake a thinning ice-cored moraine. Rock glaciers will persist in landscapes well beyond debris-free counterparts because they have much longer response times to climate change. The headwaters of alpine basins with steep headwalls will therefore oscillate between glacier and rock glacier occupation over glacial-interglacial cycles, maintaining a means by which rock from the headwall can be conveyed away. This enhances the asymmetry of alpine ridgelines, with downwind valleys biting deeply into the range crests, as originally noted by G.K. Gilbert.

  12. Modelling debris flows down general channels

    Directory of Open Access Journals (Sweden)

    S. P. Pudasaini

    2005-01-01

    Full Text Available This paper is an extension of the single-phase cohesionless dry granular avalanche model over curved and twisted channels proposed by Pudasaini and Hutter (2003. It is a generalisation of the Savage and Hutter (1989, 1991 equations based on simple channel topography to a two-phase fluid-solid mixture of debris material. Important terms emerging from the correct treatment of the kinematic and dynamic boundary condition, and the variable basal topography are systematically taken into account. For vanishing fluid contribution and torsion-free channel topography our new model equations exactly degenerate to the previous Savage-Hutter model equations while such a degeneration was not possible by the Iverson and Denlinger (2001 model, which, in fact, also aimed to extend the Savage and Hutter model. The model equations of this paper have been rigorously derived; they include the effects of the curvature and torsion of the topography, generally for arbitrarily curved and twisted channels of variable channel width. The equations are put into a standard conservative form of partial differential equations. From these one can easily infer the importance and influence of the pore-fluid-pressure distribution in debris flow dynamics. The solid-phase is modelled by applying a Coulomb dry friction law whereas the fluid phase is assumed to be an incompressible Newtonian fluid. Input parameters of the equations are the internal and bed friction angles of the solid particles, the viscosity and volume fraction of the fluid, the total mixture density and the pore pressure distribution of the fluid at the bed. Given the bed topography and initial geometry and the initial velocity profile of the debris mixture, the model equations are able to describe the dynamics of the depth profile and bed parallel depth-averaged velocity distribution from the initial position to the final deposit. A shock capturing, total variation diminishing numerical scheme is implemented to

  13. A probabilistic approach for debris impact risk with numerical simulations of debris behaviors

    International Nuclear Information System (INIS)

    Kihara, Naoto; Matsuyama, Masafumi; Fujii, Naoki

    2013-01-01

    We propose a probabilistic approach for evaluating the impact risk of tsunami debris through Monte Carlo simulations with a combined system comprising a depth-averaged two-dimensional shallow water model and a discrete element model customized to simulate the motions of floating objects such as vessels. In the proposed method, first, probabilistic tsunami hazard analysis is carried out, and the exceedance probability of tsunami height and numerous tsunami time series for various hazard levels on the offshore side of a target site are estimated. Second, a characteristic tsunami time series for each hazard level is created by cluster analysis. Third, using the Monte Carlo simulation model the debris impact probability with the buildings of interest and the exceedance probability of debris impact speed are evaluated. (author)

  14. Modeling collisions in circumstellar debris disks

    Science.gov (United States)

    Nesvold, Erika

    2015-10-01

    Observations of resolved debris disks show a spectacular variety of features and asymmetries, including inner cavities and gaps, inclined secondary disks or warps, and eccentric, sharp-edged rings. Embedded exoplanets could create many of these features via gravitational perturbations, which sculpt the disk directly and by generating planetesimal collisions. In this thesis, I present the Superparticle Model/Algorithm for Collisions in Kuiper belts and debris disks (SMACK), a new method for simultaneously modeling, in 3-D, the collisional and dynamical evolution of planetesimals in a debris disk with planets. SMACK can simulate azimuthal asymmetries and how these asymmetries evolve over time. I show that SMACK is stable to numerical viscosity and numerical heating over 107 yr, and that it can reproduce analytic models of disk evolution. As an example of the algorithm's capabilities, I use SMACK to model the evolution of a debris ring containing a planet on an eccentric orbit and demonstrate that differential precession creates a spiral structure as the ring evolves, but collisions subsequently break up the spiral, leaving a narrower eccentric ring. To demonstrate SMACK's utility in studying debris disk physics, I apply SMACK to simulate a planet on a circular orbit near a ring of planetesimals that are experiencing destructive collisions. Previous simulations of a planet opening a gap in a collisionless debris disk have found that the width of the gap scales as the planet mass to the 2/7th power (alpha = 2/7). I find that gap sizes in a collisional disk still obey a power law scaling with planet mass, but that the index alpha of the power law depends on the age of the system t relative to the collisional timescale t coll of the disk by alpha = 0.32(t/ tcoll)-0.04, with inferred planet masses up to five times smaller than those predicted by the classical gap law. The increased gap sizes likely stem from the interaction between collisions and the mean motion

  15. Projected lifetime cancer risks from exposure to regional radioactive fallout in the Marshall Islands.

    Science.gov (United States)

    Land, Charles E; Bouville, André; Apostoaei, Iulian; Simon, Steven L

    2010-08-01

    Radioactive fallout from nuclear test detonations during 1946-1958 at Bikini and Enewetak Atolls in the Marshall Islands (MI) exposed populations living elsewhere in the MI archipelago. A comprehensive analysis, presented in seven companion papers, has produced estimates of tissue-specific radiation absorbed dose to MI residents at all historically inhabited atolls from internal (ingested) and external irradiation resulting from exposure to radioactive fallout, by calendar year, and by age of the population at time of exposure. The present report deals, for the first time, with the implications of these doses for cancer risk among exposed members of the MI population. Radiation doses differed by geographic location and year of birth, and radiation-related cancer risk depends upon age at exposure and age at observation for risk. Using dose-response models based on committee reports published by the National Research Council and the National Institutes of Health, we project that, during the lifetimes of members of the MI population potentially exposed to ionizing radiation from weapons test fallout deposited during the testing period (1948-1958) and from residual radioactive sources during the subsequent 12 y (1959-1970), perhaps 1.6% (with 90% uncertainty range 0.4% to 3.4%) of all cancers might be attributable to fallout-related radiation exposures. By sub-population, the projected proportion of cancers attributable to radiation from fallout from all nuclear tests conducted in the Marshall Islands is 55% (28% to 69%) among 82 persons exposed in 1954 on Rongelap and Ailinginae, 10% (2.4% to 22%) for 157 persons exposed on Utrik, and 2.2% (0.5% to 4.8%) and 0.8% (0.2% to 1.8%), respectively, for the much larger populations exposed in mid-latitude locations including Kwajalein and in southern locations including Majuro. By cancer type, point estimates of attributable risk varied, by location, between 12% and 95% for thyroid cancer, between 2% and 78% for leukemia, and

  16. A mineralogical and granulometric study of Cayambe volcano debris avalanche deposit

    Science.gov (United States)

    Detienne, M.; Delmelle, P.; Guevara, A.; Samaniego, P.; Bustillos, J.; Sonnet, P.; Opfergelt, S.

    2013-12-01

    Volcano flank/sector collapse represents one of the most catastrophic volcanic hazards. Various volcanic and non-volcanic processes are known to decrease the stability of a volcanic cone, eventually precipitating its gravitational failure. Among them, hydrothermal alteration of volcanic rocks leading to clay mineral formation is recognized as having a large negative impact on rock strength properties. Furthermore, the presence of hydrothermal clays in the collapsing mass influences the behavior of the associated volcanic debris avalanche. In particular, clay-containing debris avalanches seem to travel farther and spread more widely than avalanches of similar volume but which do not incorporate hydrothermally-altered materials. However, the relationship between hydrothermal alteration, flank collapse and debris avalanche behavior is not well understood. The objective of this study is to better determine the volume and composition of hydrothermal clay minerals in the poorly characterized debris avalanche deposit (DAD) of Cayambe composite volcano, located in a densely populated area ~70 km northeast of Quito, Ecuador. Cayambe DAD originated from a sector collapse, which occurred less than 200 ka ago. The DAD is 10-20 m thick and has an estimated total volume of ~0.85 Km3. The H/L ratio (where H is the vertical drop and L is the travel distance of the avalanche) for Cayambe DAD is ~0.095, suggesting a high mobility. In the medial-distal zone, at 9-20 km from its source, the DAD consists of an unstratified and unsorted matrix supporting millimetric to metric clasts. It has a matrix facies (i.e. rich in particles DAD behaved as a cohesive debris flow. Analysis of 13 matrix samples reveals a large variability in particle size distribution. This may reflect poor mixing of the collapsed material during transport. The clay fraction content in the matrix ranges from 15 to 30 wt.%, and does not show a relationship with the sample position in the DAD. Mineralogical

  17. PREDICTIONS OF DISPERSION AND DEPOSITION OF FALLOUT FROM NUCLEAR TESTING USING THE NOAA-HYSPLIT METEOROLOGICAL MODEL

    Science.gov (United States)

    Moroz, Brian E.; Beck, Harold L.; Bouville, André; Simon, Steven L.

    2013-01-01

    The NOAA Hybrid Single-Particle Lagrangian Integrated Trajectory Model (HYSPLIT) was evaluated as a research tool to simulate the dispersion and deposition of radioactive fallout from nuclear tests. Model-based estimates of fallout can be valuable for use in the reconstruction of past exposures from nuclear testing, particularly, where little historical fallout monitoring data is available. The ability to make reliable predictions about fallout deposition could also have significant importance for nuclear events in the future. We evaluated the accuracy of the HYSPLIT-predicted geographic patterns of deposition by comparing those predictions against known deposition patterns following specific nuclear tests with an emphasis on nuclear weapons tests conducted in the Marshall Islands. We evaluated the ability of the computer code to quantitatively predict the proportion of fallout particles of specific sizes deposited at specific locations as well as their time of transport. In our simulations of fallout from past nuclear tests, historical meteorological data were used from a reanalysis conducted jointly by the National Centers for Environmental Prediction (NCEP) and the National Center for Atmospheric Research (NCAR). We used a systematic approach in testing the HYSPLIT model by simulating the release of a range of particles sizes from a range of altitudes and evaluating the number and location of particles deposited. Our findings suggest that the quantity and quality of meteorological data are the most important factors for accurate fallout predictions and that when satisfactory meteorological input data are used, HYSPLIT can produce relatively accurate deposition patterns and fallout arrival times. Furthermore, when no other measurement data are available, HYSPLIT can be used to indicate whether or not fallout might have occurred at a given location and provide, at minimum, crude quantitative estimates of the magnitude of the deposited activity. A variety of

  18. Predictions of dispersion and deposition of fallout from nuclear testing using the NOAA-HYSPLIT meteorological model.

    Science.gov (United States)

    Moroz, Brian E; Beck, Harold L; Bouville, André; Simon, Steven L

    2010-08-01

    The NOAA Hybrid Single-Particle Lagrangian Integrated Trajectory Model (HYSPLIT) was evaluated as a research tool to simulate the dispersion and deposition of radioactive fallout from nuclear tests. Model-based estimates of fallout can be valuable for use in the reconstruction of past exposures from nuclear testing, particularly where little historical fallout monitoring data are available. The ability to make reliable predictions about fallout deposition could also have significant importance for nuclear events in the future. We evaluated the accuracy of the HYSPLIT-predicted geographic patterns of deposition by comparing those predictions against known deposition patterns following specific nuclear tests with an emphasis on nuclear weapons tests conducted in the Marshall Islands. We evaluated the ability of the computer code to quantitatively predict the proportion of fallout particles of specific sizes deposited at specific locations as well as their time of transport. In our simulations of fallout from past nuclear tests, historical meteorological data were used from a reanalysis conducted jointly by the National Centers for Environmental Prediction (NCEP) and the National Center for Atmospheric Research (NCAR). We used a systematic approach in testing the HYSPLIT model by simulating the release of a range of particle sizes from a range of altitudes and evaluating the number and location of particles deposited. Our findings suggest that the quantity and quality of meteorological data are the most important factors for accurate fallout predictions and that, when satisfactory meteorological input data are used, HYSPLIT can produce relatively accurate deposition patterns and fallout arrival times. Furthermore, when no other measurement data are available, HYSPLIT can be used to indicate whether or not fallout might have occurred at a given location and provide, at minimum, crude quantitative estimates of the magnitude of the deposited activity. A variety of

  19. Solar Radiation Pressure Estimation and Analysis of a GEO Class of High Area-to-Mass Ratio Debris Objects

    Science.gov (United States)

    Kelecy, Tom; Payne, Tim; Thurston, Robin; Stansbery, Gene

    2007-01-01

    A population of deep space objects is thought to be high area-to-mass ratio (AMR) debris having origins from sources in the geosynchronous orbit (GEO) belt. The typical AMR values have been observed to range anywhere from 1's to 10's of m(sup 2)/kg, and hence, higher than average solar radiation pressure effects result in long-term migration of eccentricity (0.1-0.6) and inclination over time. However, the nature of the debris orientation-dependent dynamics also results time-varying solar radiation forces about the average which complicate the short-term orbit determination processing. The orbit determination results are presented for several of these debris objects, and highlight their unique and varied dynamic attributes. Estimation or the solar pressure dynamics over time scales suitable for resolving the shorter term dynamics improves the orbit estimation, and hence, the orbit predictions needed to conduct follow-up observations.

  20. Multi-layered foil capture of micrometeoroids and orbital debris in low Earth orbit

    Science.gov (United States)

    Kearsley, A.; Graham, G.

    Much of our knowledge concerning the sub-millimetre orbital debris population that poses a threat to orbiting satellites has been gleaned from examination of surfaces retrieved and subsequently analysed as part of post-flight investigations. The preservation of the hypervelocity impact-derived remnants located on these surfaces is very variable, whether of space debris or micrometeoroid origin. Whilst glass and metallic materials show highly visible impact craters when examined using optical and electron microscopes, complex mixing between the target material and the impacting particle may make unambiguous interpretation of the impactor origin difficult or impossible. Our recent detailed examination of selected multi-layered insulation (MLI) foils from the ISAS Space Flyer Unit (SFU), and our preliminary study of NASA's Trek blanket, exposed on the Mir station, show that these constructions have the potential to preserve abundant residue material of a quality sufficient for detailed analysis. Although there are still limitations on the recognition of certain sources of orbital debris, the foils complement the metal and glass substrates. We suggest that a purpose-built multi-layered foil structure may prove to be extremely effective for rapid collection and unambiguous analysis of impact- derived residues. Such a collector could be used an environmental monitor for ISS, as it would have low mass, high durability, easy deployment, recovery and storage, making it an economically viable and attractive option.

  1. Protecting Spacecraft Fragments from Exposure to Small Debris

    OpenAIRE

    V. V. Zelentsov

    2015-01-01

    Since the launch of the first artificial Earth satellite a large amount of space debris has been accumulated in near-earth space. This debris comprises the exhausted spacecrafts, final stages of rocket-carriers and boosters, technological space junk, consisting of the structure elements, which are separated when deploying the solar arrays, antennas etc., as well as when undocking a booster and a spacecraft. All the debris is divided into observable one of over 100 mm in size and unobservable ...

  2. Anthropogenic effect on avalanche and debris flow activity

    OpenAIRE

    S. A. Sokratov; Yu. G. Seliverstov; A. L. Shnyparkov; K. P. Koltermann

    2013-01-01

    The paper presents examples of the change in snow avalanches and debris flows activity due to the anthropogenic pressure on vegetation and relief. The changes in dynamical characteristics of selected snow avalanches and debris flows due to the anthropogenic activity are quantified. The conclusion is made that the anthropogenic effects on the snow avalanches and debris flows activity are more pronounced than the possible effects of the climate change. The necessity is expressed on the unavoida...

  3. Molten core debris-sodium interactions: M-Series experiments

    International Nuclear Information System (INIS)

    Sowa, E.S.; Gabor, J.D.; Pavlik, J.R.; Cassulo, J.C.; Cook, C.J.; Baker, L. Jr.

    1979-01-01

    Five new kilogram-scale experiments have been carried out. Four of the experiments simulated the situation where molten core debris flows from a breached reactor vessel into a dry reactor cavity and is followed by a flow of sodium (Ex-vessel case) and one experiment simulated the flow of core debris into an existing pool of sodium (In-vessel case). The core debris was closely simulated by a thermite reaction which produced a molten mixture of UO 2 , ZrO 2 , and stainless steel. There was efficient fragmentation of the debris in all experiments with no explosive interactions observed

  4. Understanding sources, sinks, and transport of marine debris

    Science.gov (United States)

    Law, Kara Lavender; Maximenko, Nikolai

    2011-07-01

    Fifth International Marine Debris Conference: Hydrodynamics of Marine Debris; Honolulu, Hawaii, 20 March 2011; Ocean pollution in the form of marine debris, especially plastic debris, has received increasing public and media attention in recent years through striking but frequently inaccurate descriptions of “garbage patches.” Marine debris is composed of all manufactured materials, including glass, metal, paper, fibers, and plastic, that have been deliberately dumped or that accidentally entered the marine environment. Marine debris is most visible on beaches, but it has been observed in all oceans and in such remote locations as on the deep seabed and floating in the middle of subtropical ocean gyres. While many initiatives have been developed to solve this pollution problem through prevention and cleanup efforts, there is relatively little scientific information available to assess the current status of the problem or to provide metrics to gauge the success of remediation measures. With this in mind, a full-day workshop entitled “Hydrodynamics of Marine Debris” was convened at the Fifth International Marine Debris Conference in Hawaii, bringing together observational scientists and oceanographic modelers to outline the steps necessary to quantify the major sources and sinks of marine debris and the pathways between them. The ultimate goal in integrating the two approaches of study is to quantify the basinscale and global inventory of marine debris by closing the associated mass budgets.

  5. Classification of debris flow phenomena in the Faroe Islands

    DEFF Research Database (Denmark)

    Dahl, Mads-Peter Jakob; E. Mortensen, Lis; Jensen, Niels H.

    2012-01-01

    Landslides and debris flow phenomena in particular constitute a threat to human activities in the Faroe Islands. As a contribution to ongoing landslide risk management research, this paper proposes a classification scheme for debris flow phenomena in the Faroe Islands. The scheme, produced through...... a multidisciplinary study involving geomorphological fieldwork and qualitative collection of indigenous landslide knowledge, presents physical characteristics to classify debris flow phenomena into groups named with Faroese terms. The following landslide definitions are proposed. Brekku-skriðulop (English translation...... with international landslide classification systems, significantly increases the knowledge of debris flow phenomena and promotes a consistent terminology of these within the Faroe Islands....

  6. RETROSPECTIVE RECONSTRUCTION OF INTEGRAL IODINE-131 FALLOUT FOR THE SETTLEMENTS OF THE BRYANSK REGION OF RUSSIA ON THE BASIS OF RESULTS OF IODINE-129 CONTENT IN THE SOIL DETERMINATION IN 2008

    Directory of Open Access Journals (Sweden)

    Yu. I. Gavrilin

    2009-01-01

    Full Text Available The article briefly describes the procedure of reconstruction of integral iodine-131 fallouts using fragmentary data on iodine-131 fallouts in May-June 1986, as well as results of determination (in the late period after the accident of iodine-129 concentration in the soil and values of integral fallouts of cesium-137 in the settlements of the Bryansk region of Russia. Results of estimation of integral iodine-131 fallouts (in the area of 32 soil sampling points are presented in the table form. Regularities of ratio (131I/137CsII change in the integral radionuclide fallouts are being determined and values of integral iodine-131 fallouts are being estimatedfor the other settlements of the region with the known values of integral cesium-137 fallouts. It is shown that variability of the average for settlements values of integral iodine-131 fallouts is 70 times less then variability of corresponding integral cesium-137 fallouts.

  7. Marine debris removal: one year of effort by the Georgia Sea Turtle-Center-Marine Debris Initiative.

    Science.gov (United States)

    Martin, Jeannie Miller

    2013-09-15

    Once in the marine environment, debris poses a significant threat to marine life that can be prevented through the help of citizen science. Marine debris is any manufactured item that enters the ocean regardless of source, commonly plastics, metal, wood, glass, foam, cloth, or rubber. Citizen science is an effective way to engage volunteers in conservation initiatives and provide education and skill development. The Georgia Sea Turtle Center Marine Debris Initiative (GSTC-MDI) is a grant funded program developed to engage citizens in the removal of marine debris from the beaches of Jekyll Island, GA, USA and the surrounding areas. During the first year of effort, more than 200 volunteers donated over 460 h of service to the removal of marine debris. Of the debris removed, approximately 89% were plastics, with a significant portion being cigarette materials. Given the successful first year, the GSTC-MDI was funded again for a second year. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. The Population of Optically Faint GEO Debris

    Science.gov (United States)

    Seitzer, Patrick; Barker, Ed; Buckalew, Brent; Burkhardt, Andrew; Cowardin, Heather; Frith, James; Gomez, Juan; Kaleida, Catherine; Lederer, Susan M.; Lee, Chris H.

    2016-01-01

    The 6.5-m Magellan telescope 'Walter Baade' at the Las Campanas Observatory in Chile has been used for spot surveys of the GEO orbital regime to study the population of optically faint GEO debris. The goal is to estimate the size of the population of GEO debris at sizes much smaller than can be studied with 1-meter class telescopes. Despite the small size of the field of view of the Magellan instrument (diameter 0.5-degree), a significant population of objects fainter than R = 19th magnitude have been found with angular rates consistent with circular orbits at GEO. We compare the size of this population with the numbers of GEO objects found at brighter magnitudes by smaller telescopes. The observed detections have a wide range in characteristics starting with those appearing as short uniform streaks. But there are a substantial number of detections with variations in brightness, flashers, during the 5-second exposure. The duration of each of these flashes can be extremely brief: sometimes less than half a second. This is characteristic of a rapidly tumbling object with a quite variable projected size times albedo. If the albedo is of the order of 0.2, then the largest projected size of these objects is around 10-cm. The data in this paper was collected over the last several years using Magellan's IMACS camera in f/2 mode. The analysis shows the brightness bins for the observed GEO population as well as the periodicity of the flashers. All objects presented are correlated with the catalog: the focus of the paper will be on the uncorrelated, optically faint, objects. The goal of this project is to better characterize the faint debris population in GEO that access to a 6.5-m optical telescope in a superb site can provide.

  9. Circumstellar Gas in Young Planetary Debris Disks

    Science.gov (United States)

    Roberge, A.

    Circumstellar (CS) disks orbiting young stars fall into two categories: primordial disks, composed of unprocessed interstellar dust and gas, and debris disks, produced by the destruction of solid planetary bodies. In the first class, the most abundant gas is H_2; in the second, it appears that the H_2 gas has disappeared, possibly through incorporation into gas giant planets. The lifetime of H_2 gas in a CS disk is therefore of great importance, as it dictates the timescale for the formation of giant planets. FUSE observations of H_2 in CS disk systems have shown that FUV absorption spectroscopy may sensitively probe for small amounts of gas along the line of sight to the star. Most importantly, the FUSE non-detection of H_2 gas in the Beta Pictoris disk suggests that the primordial gas lifetime is less than about 12 Myr, and that gas giant planets must form very quickly. However, this suggestion is based on one system, and needs to be tested in additional systems with a range of ages, especially since there are indications that age is not the only factor in the evolution of a CS disk. We propose for FUSE observations of 3 additional debris disk systems, Fomalhaut, HD3003, and HD2884. Fomalhaut is an intermediate age debris disk, one of the Fabulous Four CS disks first discovered in 1984. The other two disks are younger, with ages similar to that of Beta Pic. All three stars are brighter in the FUV than Beta Pic, permitting us to sensitively probe for traces of H_2 gas. We will also measure the amount of secondary atomic gas produced from planetary bodies in these disks, in an effort to understand the entire evolution of CS gas in young planetary systems.

  10. Attenuation of airborne debris from LMFBR accidents

    International Nuclear Information System (INIS)

    Morewitz, H.A.; Johnson, R.P.; Nelson, C.T.; Vaughan, E.U.; Guderjahn, C.A.; Hilliard, R.K.; McCormack, J.D.; Postma, A.K.

    1978-01-01

    Experimental and theoretical studies have been performed to characterize the behavior of airborne particulates (aerosols) expected to be produced by hypothetical core disassembly accidents (HCDA's) in liquid metal fast breeder reactors (LMFBR's). These aerosol studies include work on aerosol transport in a 20-m high, 850-m 3 closed vessel at moderate concentrations; aerosol transport in a small vessel under conditions of high concentration (approximately 1,000 g/m 3 ), high turbulence, and high temperature (approximately 2000 0 C); and aerosol transport through various leak paths. These studies have shown that tittle, if any, airborne debris from LMFBR HCDA's would reach the atmosphere exterior to an intact reactor containment building. (author)

  11. Photometric Studies of Orbital Debris at GEO

    Science.gov (United States)

    Seitzer, Patrick; Cowardin, Heather M.; Barker, Ed; Abercromby, Kira J.; Foreman, Gary; Hortsman, Matt

    2009-01-01

    Orbital debris represents a significant and increasing risk to operational spacecraft. Here we report on photometric observations made in standard BVRI filters at the Cerro Tololo Inter-American Observatory (CTIO) in an effort to determine the physical characteristics of optically faint debris at geosynchronous Earth orbit (GEO). Our sample is taken from GEO objects discovered in a survey with the University of Michigan s 0.6-m Curtis-Schmidt telescope (known as MODEST, for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the CTIO/SMARTS 0.9-m for orbits and photometry. For a sample of 50 objects, calibrated sequences in RB- V-I-R filters have been obtained with the CTIO/SMARTS 0.9-m. For objects that do not show large brightness variations, the colors are largely redder than solar in both B-R and R-I. The width of the color distribution may be intrinsic to the nature of the surfaces, but also could imply that we are seeing irregularly shaped objects and measuring the colors at different times with just one telescope. For irregularly shaped objects tumbling at unknown orientations and rates, such sequential filter measurements using one telescope are subject to large errors for interpretation. If all observations in all filters in a particular sequence are of the same surface at the same solar and viewing angles, then the colors are meaningful. Where this is not the case, interpretation of the observed colors is impossible. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO/SMARTS 0.9-m observes in B, and the Schmidt in R. The CCD cameras are electronically linked together so that the start time and duration of observations are both the same to better than 50 milliseconds. Now the observed B-R color is a true measure of the scattered illuminated area of the debris piece for that observation.

  12. Engagement of Metal Debris into Gear Mesh

    Science.gov (United States)

    handschuh, Robert F.; Krantz, Timothy L.

    2010-01-01

    A series of bench-top experiments was conducted to determine the effects of metallic debris being dragged through meshing gear teeth. A test rig that is typically used to conduct contact fatigue experiments was used for these tests. Several sizes of drill material, shim stock and pieces of gear teeth were introduced and then driven through the meshing region. The level of torque required to drive the "chip" through the gear mesh was measured. From the data gathered, chip size sufficient to jam the mechanism can be determined.

  13. United theory of biological evolution: Disaster-forced evolution through Supernova, radioactive ash fall-outs, genome instability, and mass extinctions

    Directory of Open Access Journals (Sweden)

    Toshikazu Ebisuzaki

    2015-01-01

    similar rapid speciation (though in a much smaller scale also has been undergoing in cichlid fishes and great African apes in the last several tens of thousand years in the current African rift valley, including the origin of humankind due to the radioactive ash fall-outs by continental alkaline volcanism.

  14. [Radioactive nuclides in the marine environment--distribution and behaviour of 95Zr, 95Nb originated from fallout].

    Science.gov (United States)

    Yamato, A; Miyagawa, N; Miyanaga, N

    1984-07-01

    To investigate behaviour of 95Zr, 95Nb in the marine environment, various samples have been collected and measured by means of Ge(Li) gamma-ray spectrometry and/or radiochemical analysis during a period from 1974 to 1982 at coastal area of Tokai-mura, Ibaraki prefecture. Concentration of the nuclides in seaweeds increased remarkably after atmospheric nuclear detonation by P.R. of China, and the activity ratio between the nuclides changed by time was not fit well by the transient decay equation. Concentration variation in sea water was smaller than that in sea weeds, and the minimum change in sea sediment. Increase of concentration in these environmental samples was observed in chronological order of sea water, sea weeds then sediment after detonations, suggesting that the uptake of the nuclides by these sea weeds from sea water is faster than that via root. Observed concentration factors on the nuclides by sea weeds were calculated from the observed concentrations in sea water and sea weeds. Maximum values on 95Zr and 95Nb were 2110, 2150, respectively for Ecklonia cava and Eisenia bicyclis.

  15. Investigation of Orbital Debris: Mitigation, Removal, and Modeling the Debris Population

    Science.gov (United States)

    Slotten, Joel

    The population of objects in orbit around Earth has grown since the late 1950s. Today there are over 21,000 objects over 10 cm in length in orbit, and an estimated 500,000 more between 1 and 10 cm. Only a small fraction of these objects are operational satellites. The rest are debris: old derelict spacecraft or rocket bodies, fragments created as the result of explosions or collisions, discarded objects, slag from solid rockets, or even flaked off paint. Traveling at up to 7 km/s, a collision with even a 1 cm piece of debris could severely damage or destroy a satellite. This dissertation examines three aspects of orbital debris. First, the concept of a self-consuming satellite is explored. This nanosatellite would use its own external structure as propellant to execute a deorbit maneuver at the end of its operational life, thus allowing it to meet current debris mitigation standards. Results from lab experiments examining potential materials for this concept have shown favorable results. Second, Particle in Cell techniques are modified and used to model the plasma plume from a micro-cathode arc thruster. This model is then applied to the concept of an ion beam shepherd satellite. This satellite would use its plasma plume to deorbit another derelict satellite. Results from these simulations indicate the micro-cathode arc thruster could potentially deorbit a derelict CubeSat in a matter of a few weeks. Finally, the orbital debris population at geosynchronous orbit is examined, focusing on variations in the density of the population as a function of longitude. New insights are revealed demonstrating that the variation in population density is slightly less than previously reported.

  16. Use of experimental plots for assessing Chernobyl-derived fallout of {sup 137}CS in France

    Energy Technology Data Exchange (ETDEWEB)

    Bonte, Ph.; Sogon, S.; Bourgeois, S.; Terce, M.; Morel, Ch. [Laboratoire des Sciences du Climat et de l' Environnement, avenue de la Terrasse, 91 - Gif-sur-Yvette (France)

    2004-07-01

    Caesium-137 ({sup 137}Cs) is widely used for the determination of soil erosion and sedimentation rates. However, in Europe, if the additional inputs of {sup 137}Cs fallout associated with the Chernobyl accident have given a supplementary mark to know the chronological history of buried sediments in rivers or wetlands, they have considerably complicated the interpretation of {sup 137}Cs inventories used for estimating soil redistribution on slopes. In fact, determination of Chernobyl-derived fallout {sup 137}Cs is problematic because very few sites have been correctly sampled at the moment of the accident. During the ten years after, it was possible to estimate the fallout measuring the {sup 134}Cs activity for estimating {sup 137}Cs ({sup 137}Cs /{sup 134}Cs 2.0 at the time of the accident). But these measurements are extremely rare, whereas it should be the more accurate method to resolve this question. The more used solution is to use model based on atmospheric circulation and rain precipitation, the main part of fallout been due to atmospheric washing by the rain. Other solution is to compare {sup 137}Cs specific activity of soil samples collected after the accident and older samples. Then, we choose a set of soil samples collected on several experimental plots at different places in France, and sampled before and after the Chernobyl accident, to determine the part of contamination linked to this {sup 137}Cs fallout event with a simple comparison of their {sup 137}Cs specific activity. In fact, national French institutes working on agronomy maintain experimental plots, with varied surface area (1 m{sup 2} 10 m{sup 2} or larger), for monitoring of soil physics and chemistry evolution. Nine sites were studied: two of them close to Paris, one 100 km east of Paris, 3 in Loire basin and 3 in south west, in the Pyrenees Atlantic. These measurements confirm the influence of the Chernobyl radioactive plume over the Paris Basin concerning the {sup 137}Cs fallout. The

  17. Zodiac II: Debris Disk Science from a Balloon

    Science.gov (United States)

    Bryden, Geoffrey; Traub, Wesley; Roberts, Lewis C., Jr.; Bruno, Robin; Unwin, Stephen; Backovsky, Stan; Brugarolas, Paul; Chakrabarti, Supriya; Chen, Pin; Hillenbrand, Lynne; hide

    2011-01-01

    Zodiac II is a proposed balloon-borne science investigation of debris disks around nearby stars. Debris disks are analogs of the Asteroid Belt (mainly rocky) and Kuiper Belt (mainly icy) in our Solar System. Zodiac II will measure the size, shape, brightness, and color of a statistically significant sample of disks. These measurements will enable us to probe these fundamental questions: what do debris disks tell us about the evolution of planetary systems; how are debris disks produced; how are debris disks shaped by planets; what materials are debris disks made of; how much dust do debris disks make as they grind down; and how long do debris disks live? In addition, Zodiac II will observe hot, young exoplanets as targets of opportunity. The Zodiac II instrument is a 1.1-m diameter SiC (Silicone carbide) telescope and an imaging coronagraph on a gondola carried by a stratospheric balloon. Its data product is a set of images of each targeted debris disk in four broad visible-wavelength bands. Zodiac II will address its science questions by taking high-resolution, multi-wavelength images of the debris disks around tens of nearby stars. Mid-latitude flights are considered: overnight test flights in the US followed by half-global flights in the Southern Hemisphere. These longer flights are required to fully explore the set of known debris disks accessible only to Zodiac II. On these targets, it will be 100 times more sensitive than the Hubble Space Telescope's Advanced Camera for Surveys (HST/ACS); no existing telescope can match the Zodiac II contrast and resolution performance. A second objective of Zodiac II is to use the near-space environment to raise the Technology Readiness Level (TRL) of SiC mirrors, internal coronagraphs, deformable mirrors, and wavefront sensing and control, all potentially needed for a future space-based telescope for high-contrast exoplanet imaging.

  18. Long term survey on food pollution and contamination by radioactive fallout in Fukuoka, Japan (1961 - 1976)

    International Nuclear Information System (INIS)

    Morishige, Toshiko; Ishinishi, Noburu; Cho, Tetsuji.

    1977-01-01

    The contamination and the pollution of foodstuffs by radioactive fallout have been investigated since 1961 in Fukuoka city and its suburban area. The results obtained were as follows. 1) Recently, the degree of the contamination of greens by radioactive fallout which fell on the leaves decreased to one thousandth in the early stage of the investigation (1961 - 1962). In the period of the investigation, the remarkable increase of the radioactivity of fallout was observed within a week after the Chinese nuclear bomb explosion in the atmosphere (1st, 2nd, 5th, 12th, 13th, and 15th). The radioactivity was 2 to 300 times higher than the usual level. 2) The radioactivity was not remarkable in vegetables which were washed with soap, but it decreased gradually year by year. The increase of the radioactivity was also observed a few days after the atmospheric nuclear explosion. 3) In milk, there were no remarkable yearly decreases of the radioactivity from the beginning of the investigation, but the seasonal variations of the radioactivity, such as higher in April and May, were observed. 4) The radioactivity in diets based on the standard food production in Japan was the highest in 1967. It decreased gradually from 1967 to 1971 and after that the remarkable variation of the activity was not observed. 5) 137 Cs contamination of foodstuffs has been observed quantitatively by the method of gamma spectrometry, while sometimes 95 Zr- 95 Nb, 103 Ru, and 131 I were also detected from the specimens obtained immediately after the nuclear explosions. (auth.)

  19. Early deterioration of coarse woody debris.

    Energy Technology Data Exchange (ETDEWEB)

    Tainter, Frank, H.; McMinn, James, W.

    1999-02-16

    Tainter, F.H., and J.W. McMinn. 1999. Early deterioration of coarse woody debris. In: Proc. Tenth Bien. South. Silv. Res. Conf. Shreveport, LA, February 16-18, 1999. Pp. 232-237 Abstract - Coarse woody debris (CWD) is an important structural component of southern forest ecosystems. CWD loading may be affected by different decomposition rates on sites of varying quality. Bolts of red oak and loblolly pine were placed on plots at each of three (hydric, mesic. and xerlc) sites at the Savannah River Site and sampled over a I6-week period. Major changes were in moisture content and nonstructural carbohydrate content (total carbohydrates, reducing sugars, and starch) of sapwood. Early changes in nonstructural carbohydrate levels following placement of the bolts were likely due to reallocation of these materials by sapwood parenchyma cells. These carbohydrates later formed pools increasingly metabolized by bacteria and invading fungi. Most prevalent fungi in sapwood were Ceratocysfis spp. in pine and Hypoxy/on spp. in oak. Although pine sapwood became blue stained and oak sapwood exhibited yellow soft decay with black zone lines, estimators of decay (specific gravity, sodium hydroxide solubility, and holocellulose content) were unchanged during the 16-week study period. A small effect of site was detected for starch content of sapwood of both species. Fungal biomass in sapwood of both species, as measured by ergosterol content, was detectable at week zero, increased somewhat by week three and increased significantly by week 16.

  20. Radioactive fallout from Chinese nuclear weapons test of March 15, 1978

    International Nuclear Information System (INIS)

    Thomas, C.W.

    1979-01-01

    Pacific Northwest Laboratory (PNL) has measured the radionuclide concentration of short-lived debris from a radioactive cloud, produced by a nuclear weapons test conducted by the People's Republic of China on March 15, 1978. Analysis with a 40 cfm Sierra impactor showed that a large portion of the radioactivity was associated with relatively large particles. Surface air samples showed significant concentrations of 124 Sb. Samples of rain water from New York State showed that radioactivity arrived on the east coast at about the same time as peak debris levels were observed on the west coast. Highest concentrations of 131 I occurred along the Washington State--Canadian border

  1. Determination of Fallout Beryllium-7 Concentration in Senawang and Bangi Stations, Malaysia

    International Nuclear Information System (INIS)

    Jalal Sharib; Dainee Nor Fardzilla Ahmad Tugi; Noor Fadzillah Yusof; Mohd Tarmizi Ishak

    2016-01-01

    The main objective for this paper is to determine the Beryllium-7, "7Be concentration during dry and wet fallout at two different sampling stations. Two selected sampling stations are located in Bangi, Selangor and Senawang, Negeri Sembilan which that based on the different fallout amount received annually. Meanwhile, the dry and wet fallout were collected from end of May until end of July 2015 using rain collector. The rainfall samples were brought to Radiochemistry and Environment Group (RAS) for further treatment by using chemical precipitation procedure. The filtered samples consist of "7Be concentration needs to be transferred into a Petri dish and dried in the oven for two (2) hour. The filtered samples from both locations were counting using Gamma Spectrometry for 24-hour with 20 % of the detector efficiency.The uncertainty of each "7Be concentration or activity, calculated as a γ-detector counting error at 95 % confidence level, is in the order of ±10 %. From the result showed "7Be concentration from Senawang station was lower than Bangi station in terms of concentration, which is 0.21 to 2.86 Bq l"-"1 and 0.54 to 3.55 Bq l"-"1 with an average 1.09 Bq l"-"1 and 1.53 Bq l"-"1, respectively. However, these two mean values at two sampling stations are not significant from other reports in the literature for example 0.02 to 5.90 Bq l"-"1 (Wallbrink and Murray, 1994), 0.50 to 1.59 Bq l"-"1 (Brown et al., 1988) and 0.59 to 2.74 Bq l"-"1(Peirson, 1963). Moreover, these two mean values are not to be used as reference data in Peninsula of Malaysia due to a minimal number of sampling stations been located. Therefore, a study should be carried out with more sampling stations would be selected to establish fallout "7Be data in Peninsula of Malaysia for future reference. (author)

  2. The medical effects of radioactive fall-out: role of stable end-products

    International Nuclear Information System (INIS)

    Burrows, B.A.; Cardarelli, J.C.; Boling, E.A.; Sinex, F.M.

    1980-01-01

    To summarize, from preliminary observations on the possible effects of radioactive fall-out, it may be inferred that in addition to the secondary products of ionizing irradiation per se, the stable end-products of the transmutation of certain radionuclides may adversely influence cellular metabolism, including mutagenesis. The discussion of the possible role of intracellular barium as an end-product of 137Cs decay is offered as an example of an unpredictable number of broad ecological, as well as the more limited medical, effects that may be of both clinical and climatological significance

  3. Far field nuclear fallout experience and countermeasure strategy: A cost-benefit re-appraisal

    International Nuclear Information System (INIS)

    Harbitz, O.; Reitan, J.B.; Strand, P.

    1997-01-01

    The time of the year (April, May) when the fallout occurred, had influence on the consequences. In spring no animals were out grazing and almost no standing crops could receive direct surface contamination. However, uptake and the transfer in the semi-natural ecosystem became considerable important. In semi-natural ecosystems, soils often have a low mineral content and very little clay and this usually means less findings of the radiocaesium. Even before the Chernobyl accident occurred, it was known that the root uptake of radiocaesium in a semi-natural ecosystem was higher than average in agricultural ecosystems

  4. Release and Movement of Radionuclides in Soils Contaminated with Fallout Materials from an Underground Thermonuclear Detonation

    Science.gov (United States)

    1962-07-06

    Studies The degree of dissolution of the fallout material in H2 0, HCl, DTPA, CDTA, and EDDHA solutions was investigated by the suspension method...days was: EDDHA >DTPA>CDTA>H 2 0. while after 65 days the order of effect was: CDTA> EDDHA >DTPA>H 20. Portions of gamma ray spectra of the 106 day...the same amounts of radionuclides as did H120. The most abundant radio- nuclide was radiotungsten for H120, DTPA, CDTA, and EDDHA supernatant liquids

  5. A fractal view of Chernobyl fallout in Northern Italy and Europe

    International Nuclear Information System (INIS)

    Salvadori, G.; Ratti, S.P.; Belli, G.; Quinto, E.

    1996-01-01

    Fractals are associated with irregularity and represent a powerful tool for investigating phenomena featuring a complex behaviour, as it is the case of the atmospheric processes playing a role in spreading the radioactive pollution of Chernobyl in the environment. The introduction of fractals in environmental sciences is quite recent. Fractals may account for the presence of strong fluctuations and for the high variability characterising the natural events involved in the Chernobyl fallout: the geographical sparseness of pollutant and the presence of 'hot spots' make it advisable to use fractals as a theoretical framework for modelling

  6. The transfer of fallout cesium-137 from browse to moose. Part 1

    International Nuclear Information System (INIS)

    Zach, R.; Mayoh, K.R.

    1982-09-01

    We are investigating the transfer of fallout cesium-137 from soil to browse to moose (Alces alces) to wolf (Canis lupis) to promote our understanding of the movement of radionuclides through natural food chains. The first part of this study is concerned with moose food habits. Early winter food habits of moose from Hecla Island and Manitoba Game Hunting Area 26 in south central and south eastern Manitoba were studied. In 86 rumen samples, 25 food types were identified. Three methods of food habit determination were used: (1) percentage occurrence of food types, (2) subjective abundance scores and (3) percentage dry weight. All three methods yielded very similar results

  7. Radionuclides fallout on lichens and mosses and their leaching by rain in a forest ecosystem

    International Nuclear Information System (INIS)

    Guillitte, Olivier; Kirchmann, Rene; Gelder, E. van; Hurtgen, Christian

    1990-01-01

    In the framework of the Belgian radioecological surveillance programme around nuclear power plants and of research into the impact of fallout from the nuclear accident of Chernobyl on the Ardennes forests, samples of lichens and mosses were collected and measured for radioactive content. It was observed that there is a larger variation between the samples of the same species than between various species but collected from the same ecological niche. The ecological half-life of radionuclides is also dependent on location of these organisms in the forest biotope. Some suggestions regarding the sampling standards are proposed. (author)

  8. Toxoplasma antibodies and retinochoroiditis in the Marshall Islands and their association with exposure to radioactive fallout

    International Nuclear Information System (INIS)

    Adams, W.H.; Kindermann, W.R.; Walls, K.W.; Heotis, P.M.

    1987-01-01

    Nearly universal serologic evidence of Toxoplasma gondii infection was found to have occurred by adulthood in 517 Marshallese tested in 1981-1982. The prevalence and incidence of retinal lesions compatible with toxoplasmosis were 3.9% and 273 cases/year/100,000 seropositive persons, respectively, thus indicating a significant public health problem. Seronegativity was significantly more common in a subgroup of Marshallese that had received 110-190 rads of total-body gamma radiation as a consequence of accidental exposure to radioactive fallout in 1954. Despite this finding there was no evidence of an increase in clinically significant lesions in exposed persons

  9. Contamination dynamics in fallouts, pasturable vegetation and milk in Leningrad distrist after Chernobyl accident

    International Nuclear Information System (INIS)

    Nedbaevskaya, N.A.; Sanzharova, N.I.; Blinova, L.D.; Kryshev, I.I.; Aleksakhin, R.M.

    1991-01-01

    Radiation monitoring of individual elements of agroecosystem in the area of the Leningrad NPP is carried out with the purpose of studying the concentration dynamics of radioisotopes in the atmosphere resulting from the accident at the Chernobyl NPP. The γ-radiation dose rate on the terrain, content and radionuclide composition of atmospheric fallout, content of γ-emitting isotopes in the soil and plants at pastures is monitored from April up to September 1986; radioisotope content in cow milk by pasturing is determined

  10. Use of fallout radionuclides ((7)Be, (210)Pb) to estimate resuspension of Escherichia coli from streambed sediments during floods in a tropical montane catchment.

    Science.gov (United States)

    Ribolzi, Olivier; Evrard, Olivier; Huon, Sylvain; Rochelle-Newall, Emma; Henri-des-Tureaux, Thierry; Silvera, Norbert; Thammahacksac, Chanthamousone; Sengtaheuanghoung, Oloth

    2016-02-01

    Consumption of water polluted by faecal contaminants is responsible for 2 million deaths annually, most of which occur in developing countries without adequate sanitation. In tropical aquatic systems, streambeds can be reservoirs of persistent pathogenic bacteria and high rainfall can lead to contaminated soils entering streams and to the resuspension of sediment-bound microbes in the streambed. Here, we present a novel method using fallout radionuclides ((7)Be and (210)Pbxs) to estimate the proportions of Escherichia coli, an indicator of faecal contamination, associated with recently eroded soil particles and with the resuspension of streambed sediments. We show that using these radionuclides and hydrograph separations we are able to characterize the proportion of particles originating from highly contaminated soils and that from the resuspension of particle-attached bacteria within the streambed. We also found that although overland flow represented just over one tenth of the total flood volume, it was responsible for more than two thirds of the downstream transfer of E. coli. We propose that data obtained using this method can be used to understand the dynamics of faecal indicator bacteria (FIB) in streams thereby providing information for adapted management plans that reduce the health risks to local populations. Graphical Abstract Graphical abstract showing (1) the main water flow processes (i.e. overland flow, groundwater return flow, blue arrows) and sediment flow components (i.e. resuspension and soil erosion, black arrows) during floods in the Houay Pano catchment; (2) the general principle of the method using fallout radionuclide markers (i.e. (7)Be and (210)Pbxs) to estimate E. coli load from the two main sources (i.e. streambed resuspension vs soil surface washoff); and 3) the main results obtained during the 15 May 2012 storm event (i.e. relative percentage contribution of each process to the total streamflow, values in parentheses).

  11. Linking effects of anthropogenic debris to ecological impacts.

    Science.gov (United States)

    Browne, Mark Anthony; Underwood, A J; Chapman, M G; Williams, Rob; Thompson, Richard C; van Franeker, Jan A

    2015-05-22

    Accelerated contamination of habitats with debris has caused increased effort to determine ecological impacts. Strikingly, most work on organisms focuses on sublethal responses to plastic debris. This is controversial because (i) researchers have ignored medical insights about the mechanisms that link effects of debris across lower levels of biological organization to disease and mortality, and (ii) debris is considered non-hazardous by policy-makers, possibly because individuals can be injured or removed from populations and assemblages without ecological impacts. We reviewed the mechanisms that link effects of debris across lower levels of biological organization to assemblages and populations. Using plastic, we show microplastics reduce the 'health', feeding, growth and survival of ecosystem engineers. Larger debris alters assemblages because fishing-gear and tyres kill animals and damage habitat-forming plants, and because floating bottles facilitate recruitment and survival of novel taxa. Where ecological linkages are not known, we show how to establish hypothetical links by synthesizing studies to assess the likelihood of impacts. We also consider how population models examine ecological linkages and guide management of ecological impacts. We show that by focusing on linkages to ecological impacts rather than the presence of debris and its sublethal impacts, we could reduce threats posed by debris. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  12. Linking effects of anthropogenic debris to ecological impacts

    Science.gov (United States)

    Browne, Mark Anthony; Underwood, A. J.; Chapman, M. G.; Williams, Rob; Thompson, Richard C.; van Franeker, Jan A.

    2015-01-01

    Accelerated contamination of habitats with debris has caused increased effort to determine ecological impacts. Strikingly, most work on organisms focuses on sublethal responses to plastic debris. This is controversial because (i) researchers have ignored medical insights about the mechanisms that link effects of debris across lower levels of biological organization to disease and mortality, and (ii) debris is considered non-hazardous by policy-makers, possibly because individuals can be injured or removed from populations and assemblages without ecological impacts. We reviewed the mechanisms that link effects of debris across lower levels of biological organization to assemblages and populations. Using plastic, we show microplastics reduce the ‘health’, feeding, growth and survival of ecosystem engineers. Larger debris alters assemblages because fishing-gear and tyres kill animals and damage habitat-forming plants, and because floating bottles facilitate recruitment and survival of novel taxa. Where ecological linkages are not known, we show how to establish hypothetical links by synthesizing studies to assess the likelihood of impacts. We also consider how population models examine ecological linkages and guide management of ecological impacts. We show that by focusing on linkages to ecological impacts rather than the presence of debris and its sublethal impacts, we could reduce threats posed by debris. PMID:25904661

  13. Net deployment and contact dynamics of capturing space debris objects

    NARCIS (Netherlands)

    Shan, M.

    2018-01-01

    Space debris poses a big threat to operational satellites which form a crucial infrastructure for society. According to the main source of information on space debris, the U.S. Space SurveillanceNetwork (SSN), more than 17 500 objects larger than 10 cmhave been catalogued as of February 2017. Among

  14. Optimizing of the recycling of contaminated concrete debris. Final report

    International Nuclear Information System (INIS)

    Kloeckner, J.; Rasch, H.; Schloesser, K.H.; Schon, T.

    1999-01-01

    1. Latest research: So far concrete debris from nuclear facilities has been free released or was treated as radioactive waste. 2. Objective: The objective of this study is to develop solutions and methods for recycling concrete debris. The amount of materials used in nuclear facilities should be limited and the contamination of new materials should be avoided. 3. Methods: The status of recycling was presented using examples of operating or completed decommissioning as well as available studies and literature. The quality requirements for the production of new concrete products using recycled materials has been discussed. The expected amounts of concrete debris for the next 12 years was estimated. For the proposed recycling examples, radiological and economic aspects have been considered. 4. Results: The production of qualified concrete products from concrete debris is possible by using modified receptions. Technical regulations to this are missing. There is no need for the utilization of large amounts of concrete debris for shielding walls. For the production of new shielding-containers for radioactive waste, concrete debris can be applied. Regarding the distance to a central recycling facility the use of mobile equipment can be economical. By using the concrete for filling the cavity or space in a final storage, it is possible to dispose the whole radioactive debris. 5. Application possibilities: The use of concrete debris as an inner concrete shielding in waste-containers today is already possible. For the manufacture of qualified concrete products by using recycling products, further developments and regulations are necessary. (orig.) [de

  15. Laser Remediation of Threats Posed by Small Orbital Debris

    Science.gov (United States)

    Fork, Richard L.; Rogers, Jan R.; Hovater, Mary A.

    2012-01-01

    The continually increasing amount of orbital debris in near Earth space poses an increasing challenge to space situational awareness. Recent collisions of spacecraft caused abrupt increases in the density of both large and small debris in near Earth space. An especially challenging class of threats is that due to the increasing density of small (1 mm to 10 cm dimension) orbital debris. This small debris poses a serious threat since: (1) The high velocity enables even millimeter dimension debris to cause serious damage to vulnerable areas of space assets, e.g., detector windows; (2) The small size and large number of debris elements prevent adequate detection and cataloguing. We have identified solutions to this threat in the form of novel laser systems and novel ways of using these laser systems. While implementation of the solutions we identify is challenging we find approaches offering threat mitigation within time frames and at costs of practical interest. We base our analysis on the unique combination of coherent light specifically structured in both space and time and applied in novel ways entirely within the vacuum of space to deorbiting small debris. We compare and contrast laser based small debris removal strategies using ground based laser systems with strategies using space based laser systems. We find laser systems located and used entirely within space offer essential and decisive advantages over groundbased laser systems.

  16. Active Debris Removal and the Challenges for Environment Remediation

    Science.gov (United States)

    Liou, J. C.

    2012-01-01

    Recent modeling studies on the instability of the debris population in the low Earth orbit (LEO) region and the collision between Iridium 33 and Cosmos 2251 have underlined the need for active debris removal. A 2009 analysis by the NASA Orbital Debris Program Office shows that, in order to maintain the LEO debris population at a constant level for the next 200 years, an active debris removal of about five objects per year is needed. The targets identified for removal are those with the highest mass and collision probability products in the environment. Many of these objects are spent upper stages with masses ranging from 1 to more than 8 metric tons, residing in several altitude regions and concentrated in about 7 inclination bands. To remove five of those objects on a yearly basis, in a cost-effective manner, represents many challenges in technology development, engineering, and operations. This paper outlines the fundamental rationale for considering active debris removal and addresses the two possible objectives of the operations -- removing large debris to stabilize the environment and removing small debris to reduce the threat to operational spacecraft. Technological and engineering challenges associated with the two different objectives are also discussed.

  17. ABB. CASE's GUARDIANTM Debris Resistant Fuel Assembly Design

    International Nuclear Information System (INIS)

    Dixon, D. J.; Wohlsen, W. D.

    1992-01-01

    ABB CE's experience, that 72% of all recent fuel-rod failures are caused by debris fretting, is typical. In response to this problem, ABB Combustion Engineering began supplying in the late 1980s fuel assemblies with a variety of debris resistant features, including both long-end caps and small flow holes. Now ABB CAE has developed an advanced debris resistant design concept, GUARDIAN TM , which has the advantage of capturing and retaining more debris than other designs, while displacing less plenum or active fuel volume than the long end-cap design. GUARDIAN TM design features have now been implemented into four different assembly designs. ABB CASE's GUARDIAN TM fuel assembly is an advanced debris-resistant design which has both superior filtering performance and uniquely, excellent debris retention, Retention effectively removes the debris from circulation in the coolant so that it is not able to threaten the fuel again. GUARDIAN TM features have been incorporated into four ABB. CAE fuel assembly designs. These assemblies are all fully compatible with the NSLS, and full-batch operation with GUARDIAN TM began in 1992. The number of plants of both CAE and non-CAE design which accept GUARDIAN TM for debris protection is expected to grow significantly during the next few years

  18. Original Misunderstanding

    Science.gov (United States)

    Holtzman, Alexander

    2009-01-01

    Humorist Josh Billings quipped, "About the most originality that any writer can hope to achieve honestly is to steal with good judgment." Billings was harsh in his view of originality, but his critique reveals a tension faced by students every time they write a history paper. Research is the essence of any history paper. Especially in high school,…

  19. Prediction of HAMR Debris Population Distribution Released from GEO Space

    Science.gov (United States)

    Rosengren, A.; Scheeres, D.

    2012-09-01

    The high area-to-mass ratio (HAMR) debris population is thought to have origins in the GEO region. Many of these objects are uncharacterized with apparent area-to-mass ratios of up to 30 meters squared per kilogram. The orbits of HAMR objects are highly perturbed due to the combined effect of solar radiation pressure (SRP), anomalies of the Earth gravitational field, and third-body gravitational interactions induced by the Sun and the Moon. A sound understanding of their nature, orbital evolution, and possible origin is critical for space situational awareness. The study of the orbital evolution of HAMR objects, taking into account both short-period and long-period terms, requires numerical integration of the precise set of differential equations, and the investigation of a broad range of possible parameter values. However, such computations become very costly when continuously applied over a period of several decades, as is necessary in the case of HAMR debris. It therefore seems reasonable to investigate the equations that govern the long-term behavior of orbits; such equations can be derived by the method of averaging. We have validated a semi-analytical averaged theory of HAMR object orbit evolution against high precision numerical integrations, and are able to capture the extreme dynamical behaviors reported for these objects. This new averaged model, explicitly given in terms of the eccentricity and angular momentum vectors, is several hundred times faster to numerically integrate than the non-averaged Newtonian counterpart, and provides a very accurate description of the long-term behavior. Using this model, it is possible to make predictions of how a population of HAMR objects, released into GEO orbit, will evolve over time. Our earlier analyses revealed that the population would have a range of orbits much different than circular GEO. Their orbits will suffer a sub-yearly oscillation in the eccentricity and inclination evolutions, and a longer-term drift

  20. TRANSPORT CHARACTERISTICS OF SELECTED PWR LOCA GENERATED DEBRIS

    International Nuclear Information System (INIS)

    MAJI, A. K.; MARSHALL, B.

    2000-01-01

    In the unlikely event of a Loss of Coolant Accident (LOCA) in a pressurized water reactor (PWR), break jet impingement would dislodge thermal insulation FR-om nearby piping, as well as other materials within the containment, such as paint chips, concrete dust, and fire barrier materials. Steam/water flows induced by the break and by the containment sprays would transport debris to the containment floor. Subsequently, debris would likely transport to and accumulate on the suction sump screens of the emergency core cooling system (ECCS) pumps, thereby potentially degrading ECCS performance and possibly even failing the ECCS. In 1998, the U. S. Nuclear Regulatory Commission (NRC) initiated a generic study (Generic Safety Issue-191) to evaluate the potential for the accumulation of LOCA related debris on the PWR sump screen and the consequent loss of ECCS pump net positive suction head (NPSH). Los Alamos National Laboratory (LANL), supporting the resolution of GSI-191, was tasked with developing a method for estimating debris transport in PWR containments to estimate the quantity of debris that would accumulate on the sump screen for use in plant specific evaluations. The analytical method proposed by LANL, to predict debris transport within the water that would accumulate on the containment floor, is to use computational fluid dynamics (CFD) combined with experimental debris transport data to predict debris transport and accumulation on the screen. CFD simulations of actual plant containment designs would provide flow data for a postulated accident in that plant, e.g., three-dimensional patterns of flow velocities and flow turbulence. Small-scale experiments would determine parameters defining the debris transport characteristics for each type of debris. The containment floor transport methodology will merge debris transport characteristics with CFD results to provide a reasonable and conservative estimate of debris transport within the containment floor pool and