Powered by Deep Web Technologies
Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

ARM - Field Campaign - Carbonaceous Aerosol and Radiative Effects Study  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsCarbonaceous Aerosol and Radiative Effects Study (CARES) govCampaignsCarbonaceous Aerosol and Radiative Effects Study (CARES) Campaign Links CARES Website Related Campaigns Carbonaceous Aerosol and Radiation Effects Study (CARES) - Surface Meteorological Sounding 2010.05.26, Zaveri, OSC Carbonaceous Aerosol and Radiation Effects Study (CARES) Photo-Acoustic Aerosol Light Absorption and Scattering 2010.05.26, Arnott, OSC Carbonaceous Aerosol and Radiative Effects Study (CARES): SMPS & CCN counter deployment during CARES/Cal-NEx 2010.05.04, Wang, OSC Carbonaceous Aerosol and Radiative Effects Study (CARES) Ground Based Instruments 2010.04.01, Cziczo, OSC Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Carbonaceous Aerosol and Radiative Effects Study (CARES)

2

Radiation Effects In Ceramics  

Science Conference Proceedings (OSTI)

RADIATION MATERIALS SCIENCE IN TECHNOLOGY APPLICATIONS II: Radiation Effects in Ceramics. Sponsored by: Jt. SMD/MSD Nuclear Materials ...

3

Carbonaceous Aerosols and Radiative Effects Study (CARES), g1-aircraft, sedlacek sp2  

DOE Data Explorer (OSTI)

The primary objective of the Carbonaceous Aerosol and Radiative Effects Study (CARES) in 2010 was to investigate the evolution of carbonaceous aerosols of different types and their optical and hygroscopic properties in central California, with a focus on the Sacramento urban plume.

Art Sedlacek

4

Carbonaceous Aerosols and Radiative Effects Study (CARES), g1-aircraft, sedlacek sp2  

Science Conference Proceedings (OSTI)

The primary objective of the Carbonaceous Aerosol and Radiative Effects Study (CARES) in 2010 was to investigate the evolution of carbonaceous aerosols of different types and their optical and hygroscopic properties in central California, with a focus on the Sacramento urban plume.

Art Sedlacek

2011-08-30T23:59:59.000Z

5

Effects of atomic radiation  

SciTech Connect

This book focuses on the lifelong effects of atomic radiation exposure in language understandable by the concerned layperson or the specialist in another field. The base of knowledge used is the work of the Atomic Bomb Casualty Commission and its successor since 1975 the Radiation Effects Research Foundation. Within the range of Chronic effects on human health the book provides a thorough review, although effects of nonionizing radiation, effects on structures, effects on other living species, and acute effects are not discussed.

Schull, W.J.

1995-12-31T23:59:59.000Z

6

Synchrotron Radiation Effects  

NLE Websites -- All DOE Office Websites (Extended Search)

Synchrotron Radiation Effects in the IR Solenoid Flux Excluder Peter Tenenbaum LCC-Note-0007 Draft 23-September-1998 Abstract We examine the emittance dilution due to synchrotron...

7

Cancer risk among atomic bomb survivors. The RERF Life Span Study. Radiation Effects Research Foundation  

SciTech Connect

This article summarizes the risk of cancer among the survivors of the atomic bombing of Hiroshima and Nagasaki. We focus primarily on the risk of death from cancer among individuals in the Life Span Study sample of the Radiation Effects Research Foundation from 1950 through 1985 based on recently revised dosimetry procedures. We report the risk of cancer other than leukemia among the atomic bomb survivors. We note that the number of excess deaths of radiation-induced malignant tumors other than leukemia increases with age. Survivors who were exposed in the first or second decade of life have just entered the cancer-prone age and have so far exhibited a high relative risk in association with radiation dose. Whether the elevated risk will continue or will fall with time is not yet clear, although some evidence suggests that the risk may be declining. It is important to continue long-term follow-up of this cohort to document the changes with time since exposure and to provide direct rather than projected risks over the lifetime of an exposed individual.

Shimizu, Y.; Schull, W.J.; Kato, H. (Radiation Effects Research Foundation, Hiroshima (Japan))

1990-08-01T23:59:59.000Z

8

A study of radiation damage effects on the magnetic structure of bulk Iron  

SciTech Connect

Defects, defect interactions, and defect dynamics in solids created by fast neutrons are known to have significant impact on the performance and lifetime of structural materials. A fundamental understanding of the radiation damage effects in solids is therefore of great importance in assisting the development of improved materials - materials with ultrahigh strength, toughness, and radiation resistance. In this presentation, we show our recent theoretical investigation on the magnetic structure evolution of bulk iron in the region of the radiation defects. We applied a linear scaling ab-initio method based on density functional theory with local spin density approximation, namely the locally self-consistent multiple scattering method (LSMS), to the study of magnetic moment distributions in a cascade at the damage peak and for a series of time steps as the interstitials and vacancies recombined. Atomic positions correspond to those in a low energy cascade in a 10|000 atom sample, in which the primary damage state and the evolution of all defects produced were simulated using molecular dynamics with empirical, embedded-atom inter-atomic potentials. We will discuss how a region of affected moments expands and then recedes in response to a cascade evolution.

Wang Yang [Pittsburgh Supercomputing Center, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Nicholson, D. M. C.; Stocks, G. M.; Rusanu, Aurelian; Eisenbach, Markus; Stoller, R. E. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2011-04-01T23:59:59.000Z

9

A study of radiation damage effects on the magnetic structure of bulk Iron  

Science Conference Proceedings (OSTI)

Defects, defect interactions, and defect dynamics in solids created by fast neutrons are known to have significant impact on the performance and lifetime of structural materials. A fundamental understanding of the radiation damage effects in solids is therefore of great importance in assisting the development of improved materials - materials with ultrahigh strength, toughness, and radiation resistance. In this presentation, we show our recent theoretical investigation on the magnetic structure evolution of bulk iron in the region of the radiation defects. We applied a linear scaling ab-initio method based on density functional theory with local spin density approximation, namely the locally self-consistent multiple scattering method (LSMS), to the study of magnetic moment distributions in a cascade at the damage peak and for a series of time steps as the interstitials and vacancies recombined. Atomic positions correspond to those in a low energy cascade in a 10|000 atom sample, in which the primary damage state and the evolution of all defects produced were simulated using molecular dynamics with empirical, embedded-atom inter-atomic potentials. We will discuss how a region of affected moments expands and then recedes in response to a cascade evolution. VC 2011 American Institute of Physics. [doi:10.1063/1.3553937

Wang, Yang Nmn [ORNL; Nicholson, Don M [ORNL; Stocks, George Malcolm [ORNL; Rusanu, Aurelian [ORNL; Eisenbach, Markus [ORNL; Stoller, Roger E [ORNL

2011-01-01T23:59:59.000Z

10

A study of radiation damage effects on the magnetic structure of bulk Iron  

Science Conference Proceedings (OSTI)

Defects, defect interactions, and defect dynamics in solids created by fast neutrons are known to have significant impact on the performance and lifetime of structural materials. A fundamental understanding of the radiation damage effects in solids is therefore of great importance in assisting the development of improved materials - materials with ultrahigh strength, toughness, and radiation resistance. In this presentation, we show our recent theoretical investigation on the magnetic structure evolution of bulk iron in the region of the radiation defects. We applied a linear scaling ab-initio method based on density functional theory with local spin density approximation, namely the locally self-consistent multiple scattering method (LSMS), to the study of magnetic moment distributions in a cascade at the damage peak and for a series of time steps as the interstitials and vacancies recombined. Atomic positions correspond to those in a low energy cascade in a 10|000 atom sample, in which the primary damage state and the evolution of all defects produced were simulated using molecular dynamics with empirical, embedded-atom inter-atomic potentials. We will discuss how a region of affected moments expands and then recedes in response to a cascade evolution.

Wang, Yang [Pittsburgh Supercomputing Center; Stocks, George Malcolm [ORNL; Stoller, Roger E [ORNL; Nicholson, Don M [ORNL; Rusanu, Aurelian [ORNL; Eisenbach, Markus [ORNL

2011-01-01T23:59:59.000Z

11

Radiation effects on humans  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation effects on humans Radiation effects on humans Name: Joe Kemna Location: N/A Country: N/A Date: N/A Question: I am trying to find information on radiation. I need the effects on humans, the damage it causes to the environment, and any extra information you might have on the subject. Thank you for your time. Replies: Your library should be a good place to start, but first you need to narrow your question a bit. "Radiation" means radio waves, heat, light (including the ultraviolet light that causes suntan and sunburn), and what's called "ionizing radiation." By far the major source of the first three is the Sun, while the last I believe comes principally from cosmic rays and various naturally radioactive elements like uranium and radon. The most significant manmade sources of exposure would --- I think --- be household wiring and appliances (radio), engines and heating devices (heat), lamps (light), and X-ray machines, flying at high altitude in airplanes, and living in well-insulated homes built over radon sources (ionizing radiation). Heat, light and ionizing radiation play vital roles in the ecology of the Earth. Radio, light (in particular "tanning" ultraviolet), and ionizing radiation have all been widely assumed at different times to be particularly good or particularly bad for human health. Some recent issues of public concern have been the effect of radio waves from electric transmission lines, the effect on skin cancer incidence from tanning and sunburns, the depletion of the ultraviolet-light-produced ozone in the upper atmosphere by chlorofluorocarbons (CFCs), "global warming" from the increased absorption of heat radiation from the surface by atmospheric carbon dioxide and methane, and the effect of a long exposure to low levels of ionizing radiation as for example the people of Eastern Europe are experiencing from the Chernobyl nuclear power plant accident.

12

Overview of the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES)  

Science Conference Proceedings (OSTI)

Substantial uncertainties still exist in the scientific understanding of the possible interactions between urban and natural (biogenic) emissions in the production and transformation of atmospheric aerosol and the resulting impact on climate change. The U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) program's Carbonaceous Aerosol and Radiative Effects Study (CARES) carried out in June 2010 in Central Valley, California, was a comprehensive effort designed to improve this understanding. The primary objective of the field study was to investigate the evolution of secondary organic and black carbon aerosols and their climate-related properties in the Sacramento urban plume as it was routinely transported into the forested Sierra Nevada foothills area. Urban aerosols and trace gases experienced significant physical and chemical transformations as they mixed with the reactive biogenic hydrocarbons emitted from the forest. Two heavily-instrumented ground sites - one within the Sacramento urban area and another about 40 km to the northeast in the foothills area - were set up to characterize the evolution of meteorological variables, trace gases, aerosol precursors, aerosol size, composition, and climate-related properties in freshly polluted and 'aged' urban air. On selected days, the DOE G-1 aircraft was deployed to make similar measurements upwind and across the evolving Sacramento plume in the morning and again in the afternoon. The NASA B-200 aircraft, carrying remote sensing instruments, was also deployed to characterize the vertical and horizontal distribution of aerosols and aerosol optical properties within and around the plume. This overview provides: a) the scientific background and motivation for the study, b) the operational and logistical information pertinent to the execution of the study, c) an overview of key observations and initial results from the aircraft and ground-based sampling platforms, and d) a roadmap of planned data analyses and focused modeling efforts that will facilitate the integration of new knowledge into improved representations of key aerosol processes in climate models.

Zaveri, Rahul A.; Shaw, William J.; Cziczo, D. J.; Schmid, Beat; Ferrare, R.; Alexander, M. L.; Alexandrov, Mikhail; Alvarez, R. J.; Arnott, W. P.; Atkinson, D.; Baidar, Sunil; Banta, Robert M.; Barnard, James C.; Beranek, Josef; Berg, Larry K.; Brechtel, Fred J.; Brewer, W. A.; Cahill, John F.; Cairns, Brian; Cappa, Christopher D.; Chand, Duli; China, Swarup; Comstock, Jennifer M.; Dubey, Manvendra K.; Easter, Richard C.; Erickson, Matthew H.; Fast, Jerome D.; Floerchinger, Cody; Flowers, B. A.; Fortner, Edward; Gaffney, Jeffrey S.; Gilles, Mary K.; Gorkowski, K.; Gustafson, William I.; Gyawali, Madhu S.; Hair, John; Hardesty, Michael; Harworth, J. W.; Herndon, Scott C.; Hiranuma, Naruki; Hostetler, Chris A.; Hubbe, John M.; Jayne, J. T.; Jeong, H.; Jobson, Bertram T.; Kassianov, Evgueni I.; Kleinman, L. I.; Kluzek, Celine D.; Knighton, B.; Kolesar, K. R.; Kuang, Chongai; Kubatova, A.; Langford, A. O.; Laskin, Alexander; Laulainen, Nels S.; Marchbanks, R. D.; Mazzoleni, Claudio; Mei, F.; Moffet, Ryan C.; Nelson, Danny A.; Obland, Michael; Oetjen, Hilke; Onasch, Timothy B.; Ortega, Ivan; Ottaviani, M.; Pekour, Mikhail S.; Prather, Kimberly A.; Radney, J. G.; Rogers, Ray; Sandberg, S. P.; Sedlacek, Art; Senff, Christoph; Senum, Gunar; Setyan, Ari; Shilling, John E.; Shrivastava, ManishKumar B.; Song, Chen; Springston, S. R.; Subramanian, R.; Suski, Kaitlyn; Tomlinson, Jason M.; Volkamer, Rainer M.; Wallace, Hoyt A.; Wang, J.; Weickmann, A. M.; Worsnop, Douglas R.; Yu, Xiao-Ying; Zelenyuk, Alla; Zhang, Qi

2012-08-22T23:59:59.000Z

13

A study of thermal cycling and radiation effects on indium and solder bump bonding  

Science Conference Proceedings (OSTI)

The BTeV hybrid pixel detector is constructed of readout chips and sensor arrays which are developed separately. The detector is assembled by flip-chip mating of the two parts. This method requires the availability of highly reliable, reasonably low cost fine-pitch flip-chip attachment technology. We have tested the quality of two bump-bonding technologies; indium bumps (by Advanced Interconnect Technology Ltd. (AIT) of Hong Kong) and fluxless solder bumps (by MCNC in North Carolina, USA). The results have been presented elsewhere[1]. In this paper we describe tests we performed to further evaluate these technologies. We subjected 15 indium bump-bonded and 15 fluxless solder bump-bonded dummy detectors through a thermal cycle and then a dose of radiation to observe the effects of cooling, heating and radiation on bump-bonds.

Selcuk Cihangir et al.

2001-09-12T23:59:59.000Z

14

Chronic Low Dose Radiation Effects on Radiation Sensitivity  

NLE Websites -- All DOE Office Websites (Extended Search)

Chronic Low Dose Radiation Effects on Radiation Sensitivity Chronic Low Dose Radiation Effects on Radiation Sensitivity and Chromosome Instability Induction in TK6 Cells Schwartz J.L. 1 , Jordan R. 1 , Slovic J. 1 , Moruzzi A. 1 , Kimmel R. 2 , and Liber, H.L. 3 1 University of Washington, Seattle, WA; 2 Fred Hutchinson Cancer Research Center, Seattle, WA; 3 Colorado State University, Fort Collins, Colorado There are a number of cell responses that can be detected after low dose radiation exposures including the adaptive response, low dose hypersensitivity, and induced genomic instability. The relationship between these different phenomena is unknown. In this study, we measured adaptive responses, low dose hypersensitivity, and induced genomic instability in a human B-lymphoblastoid cell model, TK6, where we could genetically modify radiation responses by either over-expression of BCL-2 or deletion of TP53. TK6

15

Unruh radiation and Interference effect  

E-Print Network (OSTI)

A uniformly accelerated charged particle feels the vacuum as thermally excited and fluctuates around the classical trajectory. Then we may expect additional radiation besides the Larmor radiation. It is called Unruh radiation. In this report, we review the calculation of the Unruh radiation with an emphasis on the interference effect between the vacuum fluctuation and the radiation from the fluctuating motion. Our calculation is based on a stochastic treatment of the particle under a uniform acceleration. The basics of the stochastic equation are reviewed in another report in the same proceeding. In this report, we mainly discuss the radiation and the interference effect.

Iso, Satoshi; Zhang, Sen

2011-01-01T23:59:59.000Z

16

Unruh radiation and Interference effect  

E-Print Network (OSTI)

A uniformly accelerated charged particle feels the vacuum as thermally excited and fluctuates around the classical trajectory. Then we may expect additional radiation besides the Larmor radiation. It is called Unruh radiation. In this report, we review the calculation of the Unruh radiation with an emphasis on the interference effect between the vacuum fluctuation and the radiation from the fluctuating motion. Our calculation is based on a stochastic treatment of the particle under a uniform acceleration. The basics of the stochastic equation are reviewed in another report in the same proceeding. In this report, we mainly discuss the radiation and the interference effect.

Satoshi Iso; Yasuhiro Yamamoto; Sen Zhang

2011-02-23T23:59:59.000Z

17

A study of thermal cycling and radiation effects on indium and solder bump bonds  

Science Conference Proceedings (OSTI)

The BTeV hybrid pixel detector is constructed of readout chips and sensor arrays which are developed separately. The detector is assembled by flip-chip mating of the two parts. This method requires the availability of highly reliable, reasonably low cost fine-pitch flip-chip attachment technology. We have tested the quality of two bump-bonding technologies; indium bumps (by Advanced Interconnect Technology Ltd. (AIT) of Hong Kong) and fluxless solder bumps (by MCNC in North Carolina, USA). The results have been presented elsewhere [1]. In this paper we describe tests we performed to further evaluate these technologies. We subjected 15 indium bump-bonded and 15 fluxless solder bump-bonded dummy detectors through a thermal cycle and then a dose of radiation to observe the effects of cooling, heating and radiation on bump-bonds. We also exercised the processes of HDI mounting and wire bonding to some of the dummy detectors to see the effect of these processes on bump bonds.

Simon Kwan et al.

2001-12-11T23:59:59.000Z

18

Transport and Mixing Patterns over Central California during the Carbonaceous Aerosol and Radiative Effects Study (CARES)  

SciTech Connect

We describe the synoptic and regional-scale meteorological conditions that affected the transport and mixing of trace gases and aerosols in the vicinity of Sacramento, California during June 2010 when the Carbonaceous Aerosol and Radiative Effects Study (CARES) was conducted. The meteorological measurements collected by various instruments deployed during the campaign and the performance of the chemistry version of the Weather Research and Forecasting model (WRF-Chem) are both discussed. WRF-Chem was run daily during the campaign to forecast the spatial and temporal variation of carbon monoxide emitted from 20 anthropogenic source regions in California to guide aircraft sampling. The model is shown to reproduce the overall circulations and boundary-layer characteristics in the region, although errors in the upslope wind speed and boundary-layer depth contribute to differences in the observed and simulated carbon monoxide. Thermally-driven upslope flows that transported pollutants from Sacramento over the foothills of the Sierra Nevada occurred every afternoon, except during three periods when the passage of mid-tropospheric troughs disrupted the regional-scales flow patterns. The meteorological conditions after the passage of the third trough were the most favorable for photochemistry and likely formation of secondary organic aerosols. Meteorological measurements and model forecasts indicate that the Sacramento pollutant plume was likely transported over a downwind site that collected trace gas and aerosol measurements during 23 periods; however, direct transport occurred during only eight of these periods. The model also showed that emissions from the San Francisco Bay area transported by intrusions of marine air contributed a large fraction of the carbon monoxide in the vicinity of Sacramento, suggesting that this source likely affects local chemistry. Contributions from other sources of pollutants, such as those in the Sacramento Valley and San Joaquin Valley, were relatively low. Aerosol layering in the free troposphere was observed during the morning by an airborne Lidar; WRF-Chem forecasts showed that mountain venting processes contributed to aged pollutants aloft in the valley atmosphere which then can be entrained into the growing boundary layer the subsequent day.

Fast, Jerome D.; Gustafson, William I.; Berg, Larry K.; Shaw, William J.; Pekour, Mikhail S.; Shrivastava, ManishKumar B.; Barnard, James C.; Ferrare, R.; Hostetler, Chris A.; Hair, John; Erickson, Matthew H.; Jobson, Tom; Flowers, Bradley; Dubey, Manvendra K.; Springston, Stephen R.; Pirce, Bradley R.; Dolislager, Leon; Pederson, J. R.; Zaveri, Rahul A.

2012-02-17T23:59:59.000Z

19

Transport and mixing patterns over Central California during the carbonaceous aerosol and radiative effects study (CARES)  

SciTech Connect

We describe the synoptic and regional-scale meteorological conditions that affected the transport and mixing of trace gases and aerosols in the vicinity of Sacramento, California during June 2010 when the Carbonaceous Aerosol and Radiative Effects Study (CARES) was conducted. The meteorological measurements collected by various instruments deployed during the campaign and the performance of the chemistry version of the Weather Research and Forecasting model (WRF-Chem) are both discussed. WRF-Chem was run daily during the campaign to forecast the spatial and temporal variation of carbon monoxide emitted from 20 anthropogenic source regions in California to guide aircraft sampling. The model is shown to reproduce the overall circulations and boundary-layer characteristics in the region, although errors in the upslope wind speed and boundary-layer depth contribute to differences in the observed and simulated carbon monoxide. Thermally-driven upslope flows that transported pollutants from Sacramento over the foothills of the Sierra Nevada occurred every afternoon, except during three periods when the passage of mid-tropospheric troughs disrupted the regional-scale flow patterns. The meteorological conditions after the passage of the third trough were the most favorable for photochemistry and likely formation of secondary organic aerosols. Meteorological measurements and model forecasts indicate that the Sacramento pollutant plume was likely transported over a downwind site that collected trace gas and aerosol measurements during 23 time periods; however, direct transport occurred during only eight of these periods. The model also showed that emissions from the San Francisco Bay area transported by intrusions of marine air contributed a large fraction of the carbon monoxide in the vicinity of Sacramento, suggesting that this source likely affects local chemistry. Contributions from other sources of pollutants, such as those in the Sacramento Valley and San Joaquin Valley, were relatively low. Aerosol layering in the free troposphere was observed during the morning by an airborne Lidar. WRF-Chem forecasts showed that mountain venting processes contributed to aged pollutants aloft in the valley atmosphere that are then entrained into the growing boundary layer the subsequent day.

Fast J. D.; Springston S.; Gustafson Jr., W. I.; Berg, L. K.; Shaw, W. J.; Pekour, M.; Shrivastava, M.; Barnard, J. C.; Ferrare, R. A.; Hostetler, C. A.; Hair, J. A.; Erickson, M.; Jobson, B. T.; Flowers, B.; Dubey, M. K.; Pierce, R. B.; Dolislager, L.; Pederson, J.; Zaveri, R. A.

2012-02-17T23:59:59.000Z

20

Radiation-Induced Bystander Effects and Relevance to Human Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation-Induced Bystander Effects and Relevance to Human Radiation Radiation-Induced Bystander Effects and Relevance to Human Radiation Exposures Review of phenomenon appears in Radiation Research Pamela Sykes and Benjamin Blyth One concern of radiobiologists is the effect radiation exposure might have on nearby unirradiated cells. For example, when only a small fraction of cells are directly hit by radiation energy, are the surrounding unirradiated cells also at an increased risk of cancer? The term "radiation-induced bystander effect" is used to describe radiation-induced biological changes that occur in unirradiated cells within an irradiated cell population. Radiation-induced bystander effects have become established in the vernacular and are considered as an authentic radiation response. However, there is still no consensus on a precise definition of the term, which

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Decomposition of radiational effects of model feedbacks  

SciTech Connect

Three separate doubled CO/sub 2/ experiments with the statistical dynamic model are used to illustrate efforts to study the climate dynamics, feedbacks, and interrelationships of meteorological parameters by decomposing and isolating their individual effects on radiation transport.

Ellsaesser, H.W.; MacCracken, M.C.; Potter, G.L.; Mitchell, C.S.

1981-08-01T23:59:59.000Z

22

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

Science Conference Proceedings (OSTI)

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

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

2007-02-07T23:59:59.000Z

23

Microphysical and Radiative Effects of Ice Clouds on Tropical Equilibrium States: A Two-Dimensional Cloud-Resolving Modeling Study  

Science Conference Proceedings (OSTI)

The microphysical and radiative effects of ice clouds on tropical equilibrium states are investigated based on three two-dimensional cloud-resolving simulations imposed by zero vertical velocity and time-invariant zonal wind and sea surface ...

Fan Ping; Zhexian Luo; Xiaofan Li

2007-07-01T23:59:59.000Z

24

Secondary radiation damage as the main cause for unexpected volume effects: A histopathologic study of the parotid gland  

Science Conference Proceedings (OSTI)

Purpose: To elucidate with a histopathological study the mechanism of region-dependent volume effects in the partly irradiated parotid gland of the rat. Methods and Materials: Wistar rats were locally X-irradiated with collimators with conformal radiation portals for 100% volume and 50% cranial/caudal partial volumes. Single doses up to 40 Gy were applied. Parotid saliva samples were collected, and the three lobes of the parotid gland were examined individually on the macro- and micromorphologic level up to 1 year after irradiation. Results: Dose-dependent loss of gland weight was observed 1 year after total or partial X-irradiation. Weight loss of the glands correlated very well with loss of secretory function. Irradiating the cranial 50% volume (implicating a shielded lateral lobe) resulted in substantially more damage in terms of weight loss and loss of secretory function than 50% caudal irradiation (shielding the ventral and dorsal lobe). Histologic examinations of the glands 1 year after irradiation revealed that the shielded lateral lobe was severely affected, in contrast to the shielded ventral and dorsal lobes. Time studies showed that irradiation of the cranial 50% volume caused late development of secondary damage in the shielded lateral lobe, becoming manifest between 240 and 360 days after irradiation. The possible clinical significance of this finding is discussed. Conclusion: It is concluded that the observed region-dependent volume effect for late function loss in the rat parotid gland after partial irradiation is mainly caused by secondary events in the shielded lateral lobe. The most probable first step (primary radiation event) in the development of this secondary damage is radiation exposure to the hilus region (located between the ventral and dorsal lobe). By injuring major excretory ducts and supply routes for blood and nerves in this area, the facility system necessary for proper functioning of the nonexposed lateral lobe is seriously affected. The unexpected volume effect in the rat might have consequences for treatment strategies in radiotherapy, implicating not only salivary glands but also other organs with a seemingly homogeneous distribution of radiosensitive elements, a situation wherein volume effects have not been anticipated up to now.

Konings, Antonius W.T. [Department of Radiation and Stress Cell Biology, University Medical Center Groningen, Groningen (Netherlands)]. E-mail: a.w.t.konings@med.umcg.nl; Faber, Hette [Department of Radiation and Stress Cell Biology, University Medical Center Groningen, Groningen (Netherlands); Cotteleer, Femmy [Department of Radiation and Stress Cell Biology, University Medical Center Groningen, Groningen (Netherlands); Vissink, Arjan [Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, Groningen (Netherlands); Coppes, Rob P. [Department of Radiation and Stress Cell Biology, University Medical Center Groningen, Groningen (Netherlands); Department of Radiation Oncology, University Medical Center Groningen, Groningen (Netherlands)

2006-01-01T23:59:59.000Z

25

Study of radiation effects on the cell structure and evaluation of the dose delivered by x-ray and {alpha}-particles microscopy  

SciTech Connect

Hard X-ray fluorescence microscopy and magnified phase contrast imaging are combined to study radiation effects on cells. Experiments were performed on freeze-dried cells at the nano-imaging station ID22NI of the European synchrotron radiation facility. Quantitative phase contrast imaging provides maps of the projected mass and is used to evaluate the structural changes due to irradiation during X-ray fluorescence experiments. Complementary to phase contrast imaging, scanning transmission ion microscopy is performed and doses of all the experiments are compared. We demonstrate the sensitivity of the proposed approach to study radiation-induced damage at the sub-cellular level.

Kosior, Ewelina; Cloetens, Peter [European Synchrotron Radiation Facility, F-38000 Grenoble (France); Deves, Guillaume; Ortega, Richard [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Bohic, Sylvain [European Synchrotron Radiation Facility, 38000 Grenoble (France); INSERM U-836 (Team 6: Synchrotron Radiation and Medical Research), Grenoble Institut of Neuroscience, F-38000 Grenoble (France)

2012-12-24T23:59:59.000Z

26

Cancer risk among children of atomic bomb survivors. A review of RERF epidemiologic studies. Radiation Effects Research Foundation  

Science Conference Proceedings (OSTI)

This article summarizes recent epidemiologic studies of cancer risk among the children of atomic bomb survivors conducted at the Radiation Effects Research Foundation. These children include two groups: (1) the in utero-exposed children (ie, those born to mothers who had been pregnant at the time of the bombings of Hiroshima and Nagasaki) and (2) the F1 population, which was conceived after the atomic-bombings and born to parents of whom one or both were atomic bomb survivors. Although from 1950 to 1984 only 18 cancer cases were identified among the in utero sample, cancer risk did appear to significantly increase as maternal uterine dose increased. However, since the observed cases are too few in number to allow a site-specific review, the increased cancer risk cannot be definitively attributed to atomic bomb radiation, as yet. For those members of the F1 population who were less than 20 years old between 1946 and 1982, cancer risk did not appear to increase significantly as parental gonadal dose increased. Follow-up of this population will continue to determine if the patterns of adult-onset cancer are altered.

Yoshimoto, Y. (Radiation Effects Research Foundation, Hiroshima (Japan))

1990-08-01T23:59:59.000Z

27

EPIDEMIOLOGICAL STUDIES ON RADIATION CARCINOGENESIS IN HUMAN POPULATIONS FOLLOWING ACUTE EXPOSURE: NUCLEAR EXPLOSIONS AND MEDICAL RADIATION  

E-Print Network (OSTI)

of Atomic Bomb Radiation Effects Life Span Study Report 8.reports derive mainly from the epidemiological studies of the Japanese atomic bomb

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

28

Effects of atomic radiation: A half-century of studies from Hiroshima and Nagasaki  

SciTech Connect

This is a notable book. For the first time, a thoroughly experienced scientist has undertaken, as the author says, {open_quotes}to present the atomic bomb survivor story in all its complexity,{close_quotes} and to aid the reader, Prof. Schull has eschewed the use of technical terms. Where this could not be done, he has defined them in the text or the glossary. The task could only have been done by someone like Prof. Schull, who in various capacities has been involved in the Japanese studies since 1949. The book therefore is not a conventional epidemiological monograph. It is addressed to both the professional and nonprofessional reader, and it includes various elements of biology; it deals with history as well as science; and it considers some of its material as in a personal essay. This is an ambitious, difficult and useful undertaking that provides much information; its writing, however, is not always quite direct and incisive.

Schull, W.J.

1996-11-01T23:59:59.000Z

29

EXPERIMENTAL STUDY OF THE THERMAL RADIATION ...  

Science Conference Proceedings (OSTI)

... developed for radiation ignition studies and was not adjusted from its normal settings which approximates to the radiation from a black body at 900 ...

2011-10-27T23:59:59.000Z

30

Radiation Effects in Nanoporous Gold  

Science Conference Proceedings (OSTI)

Foams with filament and porous sizes in the range of nanometers could be unusually resistant to radiation because radiation induced point defects cannot ...

31

Radiative Effects on Particle Acceleration via Relativistic Electromagnetic Expansion  

E-Print Network (OSTI)

We study the radiation effect on the diamagnetic relativistic pulse accelerator (DPRA) in two-and-half-dimensional particle-in-cell (PIC) plasma simulation with magnetized electron-positron plasmas. Radiation damping force is self-consistently calculated for each particle, which reduces the acceleration force and converts particle energy to radiation. The emitted radiation is strongly linearly polarized and peaked within few degrees from the direction of Poynting flux due to the relativistic acceleration by the DPRA.

Noguchi, K; Nishimura, K; Noguchi, Koichi; Liang, Edison; Nishimura, Kazumi

2004-01-01T23:59:59.000Z

32

A Study of the Solar Radiation Effect on the 4.3-?m Channels of the High-Resolution Infrared Radiation Sounder  

Science Conference Proceedings (OSTI)

Measurements of infrared radiation from the National Oceanic and Atmospheric Administration series of satellites are used to retrieve atmospheric temperature, moisture, and ozone. It is well known that the measurements from the 4.3-?m channels of ...

Larry M. McMillin; David S. Crosby

2000-10-01T23:59:59.000Z

33

Radiation effects in the environment  

Science Conference Proceedings (OSTI)

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

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

1999-04-01T23:59:59.000Z

34

A Study on the “Runaway Greenhouse Effect” with a One-Dimensional Radiative–Convective Equilibrium Model  

Science Conference Proceedings (OSTI)

A simple one-dimensional radiative–convective equilibrium model is used to investigate the relationship between the surface temperature and the outgoing infrared radiation at the top of the atmosphere. The model atmosphere has a gray infrared ...

Shinichi Nakajima; Yoshi-Yuki Hayashi; Yutaka Abe

1992-12-01T23:59:59.000Z

35

Low Dose Radiation Research Program: Low Dose Radiation Effects in  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation Effects in Differentiating Human Lens Cells Radiation Effects in Differentiating Human Lens Cells E.A. Blakely1, M.P. McNamara1, P.Y. Chang1, K.A. Bjornstad1, D. Sudar1, and A.C. Thompson2 1Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California; 2Advanced Light Source Division, Lawrence Berkeley National Laboratory, Berkeley, California. Introduction The human lens is one of the most radiosensitive organs of the body. Cataract, the opacification of the lens, is a late-appearing response to radiation damage. There are few data available on the late radiation effects of exposure in space flight to charged particle beams, the most prevalent of which are protons. Basic research in this area is needed to integrate the responses of both critical and other representative tissues

36

Using nitrogen-14 nuclear quadrupole resonance and electric field gradient information for the study of radiation effects  

Science Conference Proceedings (OSTI)

Nitrogen-14 nuclear quadrupole resonance (NQR) was used in an attempt to detect the effects of ionizing radiation on organic material. Previously reported resonances for urea were detected at 2,913.32 {+-} 0.01 kHz and 2,347.88 {+-} 0.08 kHz with associated T{sub 2}* values 780 {+-} 20 {micro}s and 523 {+-} 24 {micro}s, respectively. The previously unreported {nu}{sub {minus}} line for urea-d{sup 4} was detected at 2,381 {+-} 0.04 Khz and used to determine accurately for the first time the values for the nuclear quadrupole coupling constant {chi} (3,548.74 {+-} 0.03 kHz) and the asymmetry parameter {eta} (0.31571 {+-} 0.00007) for urea-d{sup 4}. The inverse linewidth parameter T{sub 2}* for {nu}{sub +} was measured at 928 {+-} 23 {micro}s and for {nu}{sub {minus}} at 721 {+-} 12 {micro}s. Townes and Dailey analysis was performed and urea-d{sup 4} exhibits a 0.004 increase in lone pair electronic density and a slight decrease in N-H bond electronic density, as compared to urea, probably due to the mass difference. A relationship is proposed, referred to as NQR linewidth analysis, between the dynamic spin relaxation times T{sub 2} and T{sub 2}* and the widths of the distributions of the NQR parameters. Linewidth analysis is presented as a tool for possible use in future NQR work in all area, not just radiation effects. This relationship is tested using sodium nitrite T{sub 2} and T{sub 2}* values for {nu}{sub {minus}} and {nu}{sub {minus}} as a function of temperature.

Iselin, L.H.

1995-12-01T23:59:59.000Z

37

Radiation Effects on Structural Ceramics in Fusion  

Science Conference Proceedings (OSTI)

Fusion Materials—Radiation Effects and Activation / Proceedings of the Seveth Topical Meeting on the Technology of Fusion Energy (Reno, Nevada, June 15–19, 1986)

G. R. Hopkins; R. J. Price; P. W. Trester

38

Radiative Effects on Particle Acceleration in Electromagnetic Dominated Outflows  

E-Print Network (OSTI)

Plasma outflows from gamma-ray bursts (GRB), pulsar winds, relativistic jets, and ultra-intense laser targets radiate high energy photons. However, radiation damping is ignored in conventional PIC simulations. In this letter, we study the radiation damping effect on particle acceleration via Poynting fluxes in two-and-half-dimensional particle-in-cell (PIC) plasma simulation of electron-positron plasmas. Radiation damping force is self-consistently calculated for each particle and reduces the net acceleration force. The emitted radiation is peaked within a few degrees from the direction of Poynting flux and strongly linear-polarized.

Koichi Noguchi; Edison Liang; Kazumi Nishimura

2004-12-14T23:59:59.000Z

39

Posters The Effects of Radiative Transfer  

NLE Websites -- All DOE Office Websites (Extended Search)

Posters The Effects of Radiative Transfer on Low-Level Cyclogenesis M. J. Leach and S. Raman Department of Marine, Earth and Atmospheric Sciences North Carolina State University Raleigh, North Carolina Introduction Many investigators have documented the role that thermodynamic forcing due to radiative flux divergence plays in the enhancement or generation of circulation. Most of these studies involve large-scale systems (e.g., Slingo et al. 1988), small-scale systems such as thunderstorms (Chen and Cotton 1988), and squall lines (Chin, submitted). The generation of circulation on large scales results from the creation of divergence in the upper troposphere and the maintenance of low-level potentially unstable air, and the maintenance of baroclinicity throughout

40

EPIDEMIOLOGICAL STUDIES ON RADIATION CARCINOGENESIS IN HUMAN POPULATIONS FOLLOWING ACUTE EXPOSURE: NUCLEAR EXPLOSIONS AND MEDICAL RADIATION  

E-Print Network (OSTI)

EPIDEMIOLOGICAL STUDIES ON RADIATION CARCINOGENESIS IN HUMANEXPLOSIONS AND MEDICAL RADIATION . Jacob I. Fabrikant, MD,Low Levels of Ionizing Radiation, Yale University School of

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Real-time Molecular Study of Bystander Effects of Low dose Low LET radiation Using Living Cell Imaging and Nanoparticale Optics  

SciTech Connect

In this study two novel approaches are proposed to investigate precisely the low dose low LET radiation damage and its effect on bystander cells in real time. First, a flow shear model system, which would provide us a near in vivo situation where endothelial cells in the presence of extra cellular matrix experiencing continuous flow shear stress, will be used. Endothelial cells on matri-gel (simulated extra cellular matrix) will be subjected to physiological flow shear (that occurs in normal blood vessels). Second, a unique tool (Single nano particle/single live cell/single molecule microscopy and spectroscopy; Figure A) will be used to track the molecular trafficking by single live cell imaging. Single molecule chemical microscopy allows one to single out and study rare events that otherwise might be lost in assembled average measurement, and monitor many target single molecules simultaneously in real-time. Multi color single novel metal nanoparticle probes allow one to prepare multicolor probes (Figure B) to monitor many single components (events) simultaneously and perform multi-complex analysis in real-time. These nano-particles resist to photo bleaching and hence serve as probes for unlimited timeframe of analysis. Single live cell microscopy allows one to image many single cells simultaneously in real-time. With the combination of these unique tools, we will be able to study under near-physiological conditions the cellular and sub-cellular responses (even subtle changes at one molecule level) to low and very low doses of low LET radiation in real time (milli-second or nano-second) at sub-10 nanometer spatial resolution. This would allow us to precisely identify, at least in part, the molecular mediators that are responsible of radiation damage in the irradiated cells and the mediators that are responsible for initiating the signaling in the neighboring cells. Endothelial cells subjected to flow shear (2 dynes/cm2 or 16 dynes/cm2) and exposed to 0.1, 1 and 10 cGy on coverslips will be examined for (a) low LET radiation-induced alterations of cellular function and its physiological relevance in real time; and (b) radiation damage triggered bystander effect on the neighboring unirradiated cells. First, to determine the low LET radiation induced alteration of cellular function we will examine: (i) the real time transformation of single membrane transporters in single living cells; (ii) the pump efficiency of membrane efflux pump of live cells in real time at the molecular level; (iii) the kinetics of single-ligand receptor interaction on single live cell surface (Figure C); and (iv) alteration in chromosome replication in living cell. Second, to study the radiation triggered bystander responses, we will examine one of the key signaling pathway i.e. TNF- alpha/NF-kappa B mediated signaling. TNF-alpha specific nano particle sensors (green) will be developed to detect the releasing dynamics, transport mechanisms and ligand-receptor binding on live cell surface in real time. A second sensor (blue) will be developed to simultaneously monitor the track of NF-kB inside the cell. The proposed nano-particle optics approach would complement our DOE funded study on biochemical mechanisms of TNF-alpha- NF-kappa B-mediated bystander effect.

Natarajan, Mohan [UT Health Science Center at San Antonio; Xu, Nancy R [Old Dominion University; Mohan, Sumathy [UT Health Science Center at San Antonio

2013-06-03T23:59:59.000Z

42

Top-of-Atmosphere Direct Radiative Effect of Aerosols over Global Oceans from Merged CERES and MODIS Observations  

Science Conference Proceedings (OSTI)

The direct radiative effect of aerosols (DREA) is defined as the difference between radiative fluxes in the absence and presence of aerosols. In this study, the direct radiative effect of aerosols is estimated for 46 months (March 2000–December ...

Norman G. Loeb; Natividad Manalo-Smith

2005-09-01T23:59:59.000Z

43

Triple Ion-Beam Studies of Radiation Damage Effects in a 316LN Austenitic Alloy for a High Power Spallation Neutron Source  

DOE Green Energy (OSTI)

Austenitic 316LN alloy was ion-irradiated using the unique Triple Ion Beam Facility (TIF) at ORNL to investigate radiation damage effects relevant to spallation neutron sources. The TIF was used to simulate significant features of GeV proton irradiation effects in spallation neutron source target materials by producing displacement damage while simultaneously injecting helium and hydrogen at appropriately high gas/dpa ratios. Irradiations were carried out at 80, 200, and 350 C using 3.5 MeV Fe{sup 2}, 360 keV He{sup +}, and 180 keV H{sup +} to accumulate 50 dpa by Fe, 10,000 appm of He, and 50,000 appm of H. Irradiations were also carried out at 200 C in single and dual ion beam modes. The specific ion energies were chosen to maximize the damage and the gas accumulation at a depth of {approx} 1 {micro}m. Variations in microstructure and hardness of irradiated specimens were studied using transmission electron microscopy (TEM) and a nanoindentation technique, respectively. TEM investigation yielded varying damage defect microstructures, comprising black dots, faulted and unfaulted loops, and a high number density of fine bubbles (typically less than 1 nm in diameter). With increasing temperature, faulted loops had a tendency to unfault, and bubble microstructure changed from a bimodal size distribution to a unimodal distribution. Triple ion irradiations at the three temperatures resulted in similar increases in hardness of approximately a factor of two. Individually, Fe and He ions resulted in a similar magnitude of hardness increase, whereas H ions showed only a very small effect. The present study has yielded microstructural information relevant to spallation neutron source conditions and indicates that the most important concern may be radiation induced hardening and associated ductility loss.

Lee, EH

2001-08-01T23:59:59.000Z

44

Radiation effects concerns at a spallation source  

SciTech Connect

Materials used at spallation neutron sources are exposed to energetic particle and photon radiation. Mechanical and physical properties of these materials are altered; radiation damage on the atomic scale leads to radiation effects on the macroscopic scale. Most notable among mechanical-property radiation effects in metals and metal alloys are changes in tensile strength and ductility, changes in rupture strength, dimensional stability and volumetric swelling, and dimensional changes due to stress-induced creep. Physical properties such as electrical resistivity also are altered. The fission-reactor community has accumulated a good deal of data on material radiation effects. However, when the incident particle energy exceeds 50 MeV or so, a new form of radiation damage ensues; spallation reactions lead to more energetic atom recoils and the subsequent temporal and spatial distribution of point defects is much different from that due to a fission-reactor environment. In addition, spallation reactions cause atomic transmutations with these new atoms representing an impurity in the metal. The higher-energy case is of interest at spallation sources; limited detailed data exist for material performance in this environment. 35 refs., 13 figs., 1 tab.

Sommer, W.F.

1990-01-01T23:59:59.000Z

45

Effect of multiple scattering on Cerenkov radiation from energetic electrons  

SciTech Connect

Cerenkov radiation can be used as a diagnostic tool to study energetic electrons generated in ultra-intense laser matter interactions. However, electrons suffer scattering with nuclei as they move in a medium. In this article, we theoretically study the effect of multiple scattering on Cerenkov radiation, and obtain analytical formulas under some circumstances. The results show that when the speed of an energetic electron is not close to the light speed in the medium, Cerenkov radiation is just slightly decreased due to multiple scattering. In the case that the electron speed is very close to the light speed in the medium, the effect of multiple scattering becomes significant, and the radiation is dominated by bremsstrahlung.

Zheng Jian [CAS Key Laboratory of Basic Plasma Physics and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

2013-01-15T23:59:59.000Z

46

Environmental effects on composite airframes: A study conducted for the ARM UAV Program (Atmospheric Radiation Measurement Unmanned Aerospace Vehicle)  

SciTech Connect

Composite materials are affected by environments differently than conventional airframe structural materials are. This study identifies the environmental conditions which the composite-airframe ARM UAV may encounter, and discusses the potential degradation processes composite materials may undergo when subjected to those environments. This information is intended to be useful in a follow-on program to develop equipment and procedures to prevent, detect, or otherwise mitigate significant degradation with the ultimate goal of preventing catastrophic aircraft failure.

Noguchi, R.A.

1994-06-01T23:59:59.000Z

47

The Effect of Clouds on the Earth's Solar and Infrared Radiation Budgets  

Science Conference Proceedings (OSTI)

The effect of global cloudiness on the solar and infrared components of the earth's radiation balance is studied in general circulation model experiments. A wintertime simulation is conducted in which the cloud radiative transfer calculations use ...

Gerald F. Herman; Man-Li C. Wu; Winthrop T. Johnson

1980-06-01T23:59:59.000Z

48

The Chemistry of a Dry Cloud: The Effects of Radiation and Turbulence  

Science Conference Proceedings (OSTI)

The combined effect of ultraviolet radiation and turbulent mixing on chemistry in a cloud-topped boundary layer is investigated. The authors study a flow driven by longwave radiative cooling at cloud top. They consider a chemical cycle that is ...

Jordi Vilà-Guerau de Arellano; Joannes W. M. Cuijpers

2000-05-01T23:59:59.000Z

49

Radiative Effects on Turbulent Temperature Spectra and Budgets in the Planetary Boundary Layer  

Science Conference Proceedings (OSTI)

The effects of radiative energy transfer on turbulent temperature fields are studied, and preliminary estimates show the infrared “radiative dissipation” mechanism to be dominant. Spectral computations for the idealized homogeneous-isotropic case ...

M. Coantic; O. Simonin

1984-09-01T23:59:59.000Z

50

Effects of Radiation on Adaptive Immunity: Contact Hypersensitivity Model  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation on Adaptive Immunity: Contact Hypersensitivity Model Radiation on Adaptive Immunity: Contact Hypersensitivity Model Gregory Nelson Loma Linda University Abstract It has long been appreciated that cells of the immune system are radiosensitive and use apoptosis as the primary mechanism of cell death following injury. The hypervariability of the immunoglobulin superfamily of genes expressed in lymphoid cells also led to the appreciation of the nonhomologous end joining mechanism of DNA repair. Clinically, whole body irradiation is used in treatment of some lymphomas and as an immunosuppressive agent for bone marrow transplants. Inflammation at sites of radiotherapy is a common side effect. Many studies with radiation have addressed the changes in cell populations following radiation exposure and have shown a reproducible pattern of relative sensitivities amongst

51

Radiation effects in materials for fusion reactors  

DOE Green Energy (OSTI)

The 14-MeV neutrons produced in a fusion reactor result in different irradiation damage than the equivalent fluence in a fast breeded reactor, not only because of the higher defect generation rate, but because of the production of significant concentrations of helium and hydrogen. Although no fusion test reactor exists, the effects of combined displacement damage plus helium can be studied in mixed-spectrum fission reactors for alloys containing nickel (e.g., austenitic stainless steels). The presence of helium appears to modify vacancy and interstitial recombination such that microstructural development in alloys differs between the fusion and fission reactor environments. Since mechanical properties of alloys are related to the microstructure, the simultaneous production of helium and displacement damage impacts upon key design properties such as tensile, fatigue, creep, an crack growth. Through an understanding of the basic phenomena occurring during irradiation and the relationships between microstructure and properties, alloys can be tailored to minimize radiation-induced swelling and improve mechanical properties in fusion reactor service.

Scott, J.L.; Grossbeck, M.L.; Maziasz, P.J.

1981-01-01T23:59:59.000Z

52

Radiation Effects in the Space Telecommunications Environment  

SciTech Connect

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

Fleetwood, Daniel M.; Winokur, Peter S.

1999-05-17T23:59:59.000Z

53

Surface Solar Radiation Flux and Cloud Radiative Forcing for the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP): A Satellite, Surface Observations, and Radiative Transfer Model Study  

Science Conference Proceedings (OSTI)

This study presents surface solar radiation flux and cloud radiative forcing results obtained by using a combination of satellite and surface observations interpreted by means of a simple plane-parallel radiative transfer model called 2001. This ...

Catherine Gautier; Martin Landsfeld

1997-05-01T23:59:59.000Z

54

Analytic approximate radiation effects due to Bremsstrahlung  

SciTech Connect

The purpose of this note is to provide analytic approximate expressions that can provide quick estimates of the various effects of the Bremsstrahlung radiation produced relatively low energy electrons, such as the dumping of the beam into the beam stop at the ERL or field emission in superconducting cavities. The purpose of this work is not to replace a dependable calculation or, better yet, a measurement under real conditions, but to provide a quick but approximate estimate for guidance purposes only. These effects include dose to personnel, ozone generation in the air volume exposed to the radiation, hydrogen generation in the beam dump water cooling system and radiation damage to near-by magnets. These expressions can be used for other purposes, but one should note that the electron beam energy range is limited. In these calculations the good range is from about 0.5 MeV to 10 MeV. To help in the application of this note, calculations are presented as a worked out example for the beam dump of the R&D Energy Recovery Linac.

Ben-Zvi I.

2012-02-01T23:59:59.000Z

55

Silver Clear Nylon Dressing is Effective in Preventing Radiation-Induced Dermatitis in Patients With Lower Gastrointestinal Cancer: Results From a Phase III Study  

SciTech Connect

Purpose: For patients with anal canal and advanced rectal cancer, chemoradiation therapy is a curative modality or an important adjunct to surgery. Nearly all patients treated with chemoradiation experience some degree of radiation-induced dermatitis (RID). Prevention and effective treatment of RID, therefore, is of considerable clinical relevance. The present phase III randomized trial compared the efficacy of silver clear nylon dressing (SCND) with that of standard skin care for these patients. Methods and Materials: A total of 42 rectal or anal canal cancer patients were randomized to either a SCND or standard skin care group. SCND was applied from Day 1 of radiation therapy (RT) until 2 weeks after treatment completion. In the control arm, sulfadiazine cream was applied at the time of skin dermatitis. Printed digital photographs taken 2 weeks prior to, on the last day, and two weeks after the treatment completion were scored by 10 blinded readers, who used the common toxicity scoring system for skin dermatitis. Results: The radiation dose ranged from 50.4 to 59.4 Gy, and there were no differences between the 2 groups. On the last day of RT, when the most severe RID occurs, the mean dermatitis score was 2.53 (standard deviation [SD], 1.17) for the standard and 1.67 (SD, 1.2; P=.01) for the SCND arm. At 2 weeks after RT, the difference was 0.39 points in favor of SCND (P=.39). There was considerable intraclass correlation among the 10 observers. Conclusions: Silver clear nylon dressing is effective in reducing RID in patients with lower gastrointestinal cancer treated with combined chemotherapy and radiation treatment.

Niazi, Tamim M. [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada)] [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada); Vuong, Te, E-mail: tvuong@jgh.mcgill.ca [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada)] [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada); Azoulay, Laurant [Department of Epidemiology, Jewish General Hospital, McGill University (Canada)] [Department of Epidemiology, Jewish General Hospital, McGill University (Canada); Marijnen, Corrie [Department of Clinical Oncology, Leiden University Medical Center, Amsterdam (Netherlands)] [Department of Clinical Oncology, Leiden University Medical Center, Amsterdam (Netherlands); Bujko, Kryzstof [Department of Radiotherapy, The Maria Sklodowska-Curie Memorial Cancer Centre, Warsaw (Poland)] [Department of Radiotherapy, The Maria Sklodowska-Curie Memorial Cancer Centre, Warsaw (Poland); Nasr, Elie [Department of Radiation Oncology, Hotel-Dieu de France Hospital (Lebanon)] [Department of Radiation Oncology, Hotel-Dieu de France Hospital (Lebanon); Lambert, Christine; Duclos, Marie; Faria, Sergio; David, Marc [Department of Radiation Oncology, Montreal-General-Hospital, McGill University, Montreal (Canada)] [Department of Radiation Oncology, Montreal-General-Hospital, McGill University, Montreal (Canada); Cummings, Bernard [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto (Canada)] [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto (Canada)

2012-11-01T23:59:59.000Z

56

Flow cytometric applications of tumor biology: prospects and pitfalls. [Applications in study of spontaneous dog tumors and in drug and radiation effects on cultured V79 cells  

SciTech Connect

A brief review of cytometry instrumentation and its potential applications in tumor biology is presented using our recent data. Age-distribution measurements of cells from spontaneous dog tumors and cultured cells after exposure to x rays, alpha particles, or adriamycin are shown. The data show that DNA fluorescence measurements have application in the study of cell kinetics after either radiation or drug treatment. Extensive and careful experimentation is needed to utilize the sophisticated developments in flow cytometry instrumentation.

Raju, M.R.; Johnson, T.S.; Tokita, N.; Gillette, E.L.

1979-01-01T23:59:59.000Z

57

THE HEALTH EFFECTS IN WOMEN EXPOSED TO LOW-LEVELS OF IONIZING RADIATION  

E-Print Network (OSTI)

and Effects of Ionizing Radiation. New York, United Nations,Effects of Ionizing Radiation (BEIR III). The EffectsLevels of Ionizing Radiation. Washington, D.C. , National

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

58

The ionizing radiation environment in space and its effects  

Science Conference Proceedings (OSTI)

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

Adams, Jim; Falconer, David; Fry, Dan [Center for Space Plasma and Aeronomic Research (CSPAR), UA Huntsville (United States); Space Radiation Analysis Group, NASA Johnson Space Center (United States)

2012-11-20T23:59:59.000Z

59

Quantitative effect of combined chemotherapy and fractionated radiotherapy on the incidence of radiation-induced lung damage: A prospective clinical study  

SciTech Connect

The objective of this work was to assess the incidence of radiological changes compatible with radiation-induced lung damage as determined by computed tomography (CT), and subsequently calculate the dose effect factors (DEF) for specified chemotherapeutic regimens. Radiation treatments were administered once daily, 5 days-per-week. Six clinical protocols were evaluated: ABVD (adriamycin, bleomycin, vincristine, and DTIC) followed by 35 Gy in 20 fractions; MOPP (nitrogen mustard, vincristine, procarbazine, and prednisone) followed by 35 Gy in 20; MOPP/ABVD followed by 35 Gy in 20; CAV (cyclophosphamide, adriamycin, and vincristine) followed by 25 Gy in 10; and 5-FU (5-fluorouracil) concurrent with either 50-52 Gy in 20-21 or 30-36 Gy in 10-15 fractions. CT examinations were taken before and at predetermined intervals following radiotherapy. CT evidence for the development of radiation-induced damage was defined as an increase in lung density within the irradiated volume. The radiation dose to lung was calculated using a CT-based algorithm to account for tissue inhomogeneities. Different fractionation schedules were converted using two isoeffect models, the estimated single dose (ED) and the normalized total dose (NTD). The actuarial incidence of radiological pneumonitis was 71% for the ABVD, 49% for MOPP, 52% for MOPP/ABVD, 67% for CAV, 73% for 5-FU radical, and 58% for 5-FU palliative protocols. Depending on the isoeffect model selected and the method of analysis, the DEF was 1.11-1.14 for the ABVD, 0.96-0.97 for the MOPP, 0.96-1.02 for the MOPP/ABVD, 1.03-1.10 for the CAV, 0.74-0.79 for the 5-FU radical, and 0.94 for the 5-FU palliative protocols. DEF were measured by comparing the incidence of CT-observed lung damage in patients receiving chemotherapy and radiotherapy to those receiving radiotherapy alone. The addition of ABVD or CAV appeared to reduce the tolerance of lung to radiation. 40 refs., 3 figs., 3 tabs.

Mah, K.; Van Dyk, J.; Braban, L.E.; Hao, Y.; Keane, T.J. (Univ. of Toronto, Ontario (Canada)); Poon, P.Y. (Univ. of British Columbia (Canada))

1994-02-01T23:59:59.000Z

60

Effects of prenatal exposure to ionizing radiation  

SciTech Connect

Prenatal exposure to ionizing radiation induces some effects that are seen at birth and others that cannot be detected until later in life. Data from A-bomb survivors in Hiroshima and Nagasaki show a diminished number of births after exposure under 4 wk of gestational age. Although a wide array of congenital malformations has been found in animal experimentation after such exposure to x rays, in humans only small head size (exposure at 4-17 wk) and mental retardation (exposure primarily at 8-15 wk) have been observed. In Hiroshima, small head size occurred after doses of 0.10-0.19 Gy or more, and an excess of mental retardation at 0.2-0.4 Gy or more. Intelligence test scores were reduced among A-bomb survivors exposed at 8-15 wk of gestational age by 21-29 IQ points per Gy. Other effects of in-utero exposure to atomic radiation include long-lasting complex chromosome abnormalities.

Miller, R.W. (National Cancer Institute, Bethesda, MD (USA))

1990-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Radiative Effects of Cloud-Type Variations  

Science Conference Proceedings (OSTI)

Radiative flux changes induced by the occurrence of different cloud types are investigated using International Satellite Cloud Climatology Project cloud data and a refined radiative transfer model from National Aeronautics and Space ...

Ting Chen; William B. Rossow; Yuanchong Zhang

2000-01-01T23:59:59.000Z

62

Japan Program - Radiation Effects Research Foundation (RERF)  

NLE Websites -- All DOE Office Websites (Extended Search)

Safety Safety Home Sub Offices › Worker Safety & Health Policy › Worker Safety & Health Assistance › Illness & Injury Prevention Programs › International Health Studies › Office of Worker Screening and Compensation Support Mission & Functions › Health & Safety › Worker Safety & Health Policy › Worker Safety & Health Assistance › Illness & Injury Prevention Programs › International Health Studies › Worker Screening and Compensation Support Federal Line Management Oversight of DOE Nuclear Facilities Integrated Safety Management (ISM) A-Z Index Directory OSH Regulatory and Policy Response Line Health Resources Policy and Standards Worker Safety Beryllium Chemical Safety Biological Safety Radiation Safety Rules 10 CFR 707 10 CFR 835

63

Quantum radiation reaction effects in multiphoton Compton scattering  

E-Print Network (OSTI)

Radiation reaction effects in the interaction of an electron and a strong laser field are investigated in the realm of quantum electrodynamics. We identify quantum radiation reaction with the multiple photon recoils experienced by the laser-driven electron due to consecutive incoherent photon emissions. After determining a quantum radiation dominated regime, we demonstrate how in this regime quantum signatures of radiation reaction strongly affect multiphoton Compton scattering spectra and that they could be measurable in principle with presently available laser technology.

A. Di Piazza; K. Z. Hatsagortsyan; C. H. Keitel

2010-07-28T23:59:59.000Z

64

Atomistic Simulations of Radiation Effects in Ceramics for Nuclear ...  

Science Conference Proceedings (OSTI)

This work is supported by the DOE Nuclear Energy Advanced Modeling and ... Simulations of Radiation Effects in Ceramics for Nuclear Waste Disposal.

65

Radiation Effects on a High Strength, High Conductivity Copper Alloy  

Science Conference Proceedings (OSTI)

Presentation Title, Radiation Effects on a High Strength, High Conductivity Copper ... of Zircaloy during Low Dose Neutron Irradiation at Nominally 375-440° C.

66

Effect of circumsolar radiation on performance of focusing collectors  

Science Conference Proceedings (OSTI)

Circumsolar radiation is one of several factors, along with optical errors (contour, tracking, etc.), that determine the size and shape of the solar image at the receiver of a concentrating collector. The sensitivity of a collector to circumsolar radiation depends on insolation conditions and on collector parameters; it increases with geometrical concentration ratio and decreases with operating threshold. The Lawrence Berkeley Laboratory (LBL) circumsolar data are used to develop fast computational procedures for calculating the effect of circumsolar radiation on both the instantaneous and the long-term average performance of focusing collectors. For predictions of long-term average performance, a standard synthetic circumsolar scan has been developed that describes the brightness distribution of the solar disk (limb darkening) and of the circumsolar region. The radiation intercepted by a receiver is calculated separately for the solar portion and for the circumsolar portion of this standard sun shape, and these two contributions are then weighted according to the long-term average circumsolar ratio for the location and period under study.

Bendt, P.; Rabl, A.

1980-04-01T23:59:59.000Z

67

Incorporating the Effects of 3D Radiative Transfer in the Presence of Clouds into Two-Stream Multilayer Radiation Schemes  

Science Conference Proceedings (OSTI)

This paper presents a new method for representing the important effects of horizontal radiation transport through cloud sides in two-stream radiation schemes. Ordinarily, the radiative transfer equations are discretized separately for the clear ...

Robin J. Hogan; Jonathan K. P. Shonk

2013-02-01T23:59:59.000Z

68

Survey of Radiation Effects in Titanium Alloys  

Science Conference Proceedings (OSTI)

Information on radiation effects in titanium alloys has been reviewed. Only sparse experimental data from fission reactor and charged particle irradiations is available, none of which is directly applicable to the SNS. Within this limited data it is found that although mechanical properties are substantially degraded, several Ti alloys may retain acceptable properties to low or moderate doses. Therefore, it is recommended that titanium alloys be examined further for application to the SNS target. Since information directly relevant to the SNS mercury target environment and irradiation conditions is not available, it is recommended that ORNL generate the necessary experimental data using a graded approach. The first testing would be for cavitation erosion resistance using two different test devices. If the material performs acceptably the next tests should be for long term mercury compatibility testing of the most promising alloys. Irradiation tests to anticipated SNS displacement doses followed by mechanical property measurements would be the last stage in determining whether the alloys should be considered for service in the SNS target module.

Mansur, Louis K [ORNL

2008-08-01T23:59:59.000Z

69

Third Radiation Effects Research Foundation Board of Councilors Meeting  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Third Radiation Effects Research Foundation Board of Councilors Third Radiation Effects Research Foundation Board of Councilors Meeting Held in Hiroshima Third Radiation Effects Research Foundation Board of Councilors Meeting Held in Hiroshima July 22, 2013 - 4:54pm Addthis Third Radiation Effects Research Foundation Board of Councilors Meeting Held in Hiroshima The third Board of Councilors (BOC) meeting was held on June 18-19 at the Hiroshima Radiation Effects Research Foundation (RERF), a bi-national U.S.-Japan research organization. The BOC is the highest decision-making body at RERF, consisting of eight Councilors elected from the United States and Japan. A total of 23 participants, including 8 Councilors from the United States and Japan and officials from the U.S. and Japanese Governments, were present at the meeting. The Office of Health, Safety and

70

Dynamic Effects on the Tropical Cloud Radiative Forcing and Radiation Budget  

Science Conference Proceedings (OSTI)

Vertical velocity is used to isolate the effect of large-scale dynamics on the observed radiation budget and cloud properties in the tropics, using the methodology suggested by Bony et al. Cloud and radiation budget quantities in the tropics show ...

Jian Yuan; Dennis L. Hartmann; Robert Wood

2008-06-01T23:59:59.000Z

71

PLANNING STUDY FOR ADVANCED NATIONAL SYNCHROTRON-RADIATION FACILITIES  

NLE Websites -- All DOE Office Websites (Extended Search)

FOR ADVANCED NATIONAL SYNCHROTRON-RADIATION FACILITIES Printed March 14, 1984 The report of a study sponsored by the Department of Energy, Office of Basic Energy Sciences, and...

72

The One Million U.S. Radiation Worker Study  

NLE Websites -- All DOE Office Websites (Extended Search)

for chronic radiation exposure. Much knowledge has been gained from the study of atomic bomb survivors, but exposure was acute and 2 among a Japanese population living in...

73

Errors and Uncertainties in Dose Reconstruction for Radiation Effects Research  

SciTech Connect

Dose reconstruction for studies of the health effects of ionizing radiation have been carried out for many decades. Major studies have included Japanese bomb survivors, atomic veterans, downwinders of the Nevada Test Site and Hanford, underground uranium miners, and populations of nuclear workers. For such studies to be credible, significant effort must be put into applying the best science to reconstructing unbiased absorbed doses to tissues and organs as a function of time. In many cases, more and more sophisticated dose reconstruction methods have been developed as studies progressed. For the example of the Japanese bomb survivors, the dose surrogate “distance from the hypocenter” was replaced by slant range, and then by TD65 doses, DS86 doses, and more recently DS02 doses. Over the years, it has become increasingly clear that an equal level of effort must be expended on the quantitative assessment of uncertainty in such doses, and to reducing and managing uncertainty. In this context, this paper reviews difficulties in terminology, explores the nature of Berkson and classical uncertainties in dose reconstruction through examples, and proposes a path forward for Joint Coordinating Committee for Radiation Effects Research (JCCRER) Project 2.4 that requires a reasonably small level of effort for DOSES-2008.

Strom, Daniel J.

2008-04-14T23:59:59.000Z

74

Experimental methodology for non-thermal effects of electromagnetic radiation on biologics  

E-Print Network (OSTI)

Appropriate equipment is needed for research on the effects of radio-frequency radiation from radio-frequency identification (RF-ID) systems on biological materials. In the present study, a complete test system comprising ...

Cox, Felicia C. A. I

2006-01-01T23:59:59.000Z

75

Multiyear Statistics of 2D Shortwave Radiative Effects at Three ARM Sites  

Science Conference Proceedings (OSTI)

This study examines the importance of horizontal photon transport effects, which are not considered in the 1D calculations of solar radiative heating used by most atmospheric dynamical models. In particular, the paper analyzes the difference ...

Tamás Várnai

2010-11-01T23:59:59.000Z

76

Coherent Radiation Effects in the LCLS Undulator  

Science Conference Proceedings (OSTI)

For X-ray Free-Electron Lasers such as LCLS and TESLA FEL, a change in the electron energy while amplifying the FEL radiation can shift the resonance condition out of the bandwidth of the FEL. The largest sources of energy loss is the emission of incoherent undulator radiation. Because the loss per electron depends only on the undulator parameters and the beam energy, which are fixed for a given resonant wavelength, the average energy loss can be compensated for by a fixed taper of the undulator. Coherent radiation has a strong enhancement proportional to the number of electrons in the bunch for frequencies comparable to or longer than the bunch dimension. If the emitted coherent energy becomes comparable to that of the incoherent emission, it has to be included in the taper as well. However, the coherent loss depends on the bunch charge and the applied compression scheme and a change of these parameters would require a change of the taper. This imposes a limitation on the practical operation of Free-Electron Lasers, where the taper can only be adjusted manually. In this presentation we analyze the coherent emission of undulator radiation and transition undulator radiation for LCLS, and estimate whether the resulting energy losses are significant for the operation of LCLS.

Reiche, S.; /UCLA; Huang, Z.; /SLAC

2010-12-14T23:59:59.000Z

77

RADIATION EFFECTS OF ALPHA PARTICLES ON URANIUM HEXAFLUORIDE  

SciTech Connect

Alpha irradiation of uranium hexafluoride results in the formation of fluorine and intermediate, solid uranium fluorides: these products react with each other, apparently by a radiation-induced process. to reform uranium hexifluoride. The number of molecules of uranium hexafluoride decomposed, excluding recombiapproximately 1 in the temperature range 21 to 87 deg C. Irradiation of a mixture of fluorine and uranium hexafluoride in a vessel containing uranium fluorides substantistes the postulated mechanism. At fluorine pressures of 50 to 100 mm Hg, there is an increase, rather than a decrease, in uranium hexafluoride pressure. Rates of both decomposition and recombination processes appear to depend only on the rates of radiation energy absorption. Equations formnulated to describe the combined decomposition and reformation reactions can be used to calculate equilibrium concentrations of uranium hexfluoride and fluorine when the intensity of the radiation source is defined. The effects of three diluent gases, helium, nitrogen and oxygen, were studied in an attempt to find possible electron transfer processes. (auth)

Bernhardt, H.A.; Davis, W. Jr.; Shiflett, C.H.

1958-06-01T23:59:59.000Z

78

Radiation Damage Study for PHENIX Silicon Stripixel Sensors  

E-Print Network (OSTI)

Silicon stripixel sensors which were developed at BNL will be installed as part of the RHIC-PHENIX silicon vertex tracker (VTX). RHIC II operations provide luminosity up to 2x10^32 /cm2/s so the silicon stripixel sensors will be exposed to a significant amount of radiation. The most problematic radiation effect for VTX is the increase of leakage current, which degrades the signal to noise ratio and may saturate the readout electronics. We studied the radiation damage using the same diodes as CERN-RD48. First, the proportionality between the irradiation fluence and the increase of leakage current of CERN-RD48 was reproduced. Then beam experiments with stripixel sensor were done in which leakage current was found to increase in the same way as that of thereference diode. A stripixel sensor was also irradiated at the PHENIX interaction region (IR) during the 2006 run. We found the same relation between the integrated luminosity and determined fluence from increase of leakage current. The expected fluence is 3-6x10^12 Neq/cm2 (1 MeV neutron equivalent) in RHIC II operations for 10 years. Due to this expected exposure, setting the operating temperature in PHENIX to T< 0 deg. C to suppress leakage current is needed to avoid saturation of preamplifiers.

J. Asai; S. Batsouli; K. Boyle; V. Castillo; V. Cianciolo; D. Fields; C. Haegeman; M. Hoeferkamp; Y. Hosoi; R. Ichimiya; Y. Inoue; M. Kawashima; T. Komatsubara; K. Kurita; Z. Li; D. Lynch; M. Nguyen; T. Murakami; R. Nouicer; H. Ohnishi; R. Pak; K. Sakashita; T. -A. Shibata; K. Suga; A. Taketani; J. Tojo

2007-10-14T23:59:59.000Z

79

Effects of Microwave Radiation on Oil Recovery  

Science Conference Proceedings (OSTI)

A variety of oil recovery methods have been developed and applied to mature and depleted reservoirs in order to improve the efficiency. Microwave radiation oil recovery method is a relatively new method and has been of great interest in the recent years. Crude oil is typically co?mingled with suspended solids and water. To increase oil recovery

2011-01-01T23:59:59.000Z

80

COMPARING THE EFFECT OF RADIATIVE TRANSFER SCHEMES ON CONVECTION SIMULATIONS  

Science Conference Proceedings (OSTI)

We examine the effect of different radiative transfer schemes on the properties of three-dimensional (3D) simulations of near-surface stellar convection in the superadiabatic layer, where energy transport transitions from fully convective to fully radiative. We employ two radiative transfer schemes that fundamentally differ in the way they cover the 3D domain. The first solver approximates domain coverage with moments, while the second solver samples the 3D domain with ray integrations. By comparing simulations that differ only in their respective radiative transfer methods, we are able to isolate the effect that radiative efficiency has on the structure of the superadiabatic layer. We find the simulations to be in good general agreement, but they show distinct differences in the thermal structure in the superadiabatic layer and atmosphere.

Tanner, Joel D.; Basu, Sarbani; Demarque, Pierre [Astronomy Department, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States)

2012-11-10T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Effects of Penetrative Radiation on the Upper Tropical Ocean Circulation  

Science Conference Proceedings (OSTI)

The effects of penetrative radiation on the upper tropical ocean circulation have been investigated with an ocean general circulation model (OGCM) with attenuation depths derived from remotely sensed ocean color data. The OGCM is a reduced ...

Raghu Murtugudde; James Beauchamp; Charles R. McClain; Marlon Lewis; Antonio J. Busalacchi

2002-03-01T23:59:59.000Z

82

Correction of Marine Air Temperature Observations for Solar Radiation Effects  

Science Conference Proceedings (OSTI)

The effect of incoming solar radiation on merchant ships' observations of air temperature was assessed as part of the Voluntary Observing Ships' Special Observing Project for the North Atlantic (VSOP-NA), The ships' reports were compared with ...

Elizabeth C. Kent; Raoul J. Tiddy; Peter K. Taylor

1993-12-01T23:59:59.000Z

83

Runaway Greenhouse Effect in a Semigray Radiative–Convective Model  

Science Conference Proceedings (OSTI)

The effects of the nongray absorption (i.e., atmospheric opacity varying with wavelength) on the possible upper bound of the outgoing longwave radiation (OLR) emitted by a planetary atmosphere have been examined. This analysis is based on the ...

T. Pujol; G. R. North

2002-10-01T23:59:59.000Z

84

Effective Diameter in Radiation Transfer: General Definition, Applications, and Limitations  

Science Conference Proceedings (OSTI)

Although the use of an effective radius for radiation transfer calculations in water clouds has been common for many years, the export of this concept to ice clouds has been fraught with uncertainty, due to the nonspherical shapes of ice ...

David L. Mitchell

2002-08-01T23:59:59.000Z

85

Effects of low-dose radiation on immune cell function using genetic and  

NLE Websites -- All DOE Office Websites (Extended Search)

low-dose radiation on immune cell function using genetic and low-dose radiation on immune cell function using genetic and metabolomics approaches Henghong Li Georgetown University Abstract The objectives of this study are to investigate acute and persistent effects of ionizing radiation and space radiation on immune cell subsets and function. The role(s) for p38 MAP kinase in such radiation responses is being investigated using a genetic approach where an engineered mouse line has had one wt p38α gene replaced with a dominantnegative mutant (p38α+/DN). T cells are one of the most radiosensitive cell types in vivo, and radiation is known to impact CD4 T cell function long term. T cells are normally activated by antigen, which triggers differentiation to specific subsets involving various cytokines. In addition, T cells have a

86

A study of longwave radiation codes for climate studies: Validation with ARM observations and tests in general circulation models  

SciTech Connect

Research by the US Department of Energy (DOE) has shown that cloud radiative feedback is the single most important effect determining the magnitude of possible climatic responses to human activity. However, these effects are still not known at the levels needed for climate prediction. Consequently, DOE has launched a major initiative-- the Atmospheric Radiation Measurements (ARM) Program -- directed at improving the parameterization of the physics governing cloud and radiative processes in general circulation models (GCM's). One specific goal of ARM is to improve the treatment of radiative transfer in GCM's under clear-sky, general overcast and broken cloud conditions. Our approach to developing the radiation model will be to test existing models in an iterative, predictive fashion. We will supply the Clouds and Radiative Testbed (CART) with a set of models to be compared with operationally observed data. The differences we find will lead to the development of new models to be tested with new data. Similarly, our GCM studies will use existing GCM's to study the radiation sensitivity problem. We anticipate that the outcome of this approach will provide both a better longwave radiative forcing algorithm and a better understanding of how longwave radiative forcing influences the equilibrium climate of the atmosphere.

Ellingson, R.G.; Baer, F.

1992-01-01T23:59:59.000Z

87

IMPRINTED GENES & TRANSPOSITIONS: EPIGENOMIC TARGETS FOR LOW DOSE RADIATION EFFECTS  

Science Conference Proceedings (OSTI)

The overall hypothesis of this grant application is that low dose ionizing radiation (LDIR) elicits adaptive responses in part by causing heritable DNA methylation changes in the epigenome. This novel postulate was tested by determining if the level of DNA methylation at the Agouti viable yellow (A{sup vy}) metastable locus is altered, in a dose-dependent manner, by low dose radiation exposure (radiation hormesis, bringing into question the assumption that every dose of radiation is harmful. Our findings not only have significant implications concerning the mechanism of hormesis, but they also emphasize the potential importance of this phenomenon in determining human risk at low radiation doses. Since the epigenetic regulation of genes varies markedly between species, the effect of LDIR on other epigenetically labile genes (e.g. imprinted genes) in animals and humans needs to be defined.

Randy Jirtle

2012-10-11T23:59:59.000Z

88

Low Dose Radiation Research Program: Effects of Low Doses of Radiation on  

NLE Websites -- All DOE Office Websites (Extended Search)

Abstract Abstract Title: Effects of Low Doses of Radiation on DNA Repair (PNNL Project # 42699) Authors: Eric J. Ackerman, Ph.D. Institutions: Pacific Northwest National Laboratory Richland, WA We developed a functional assay to measure the effects of LDR on repair of many different lesions representative of those found in cells as consequences of normal oxidative metabolism, as well as those caused by radiation. Currently only 1/10th attomole =105 damaged molecules/cell and 3000 cells/measurement are required. We have found that even low doses (10 rad) exert measurable effects on DNA repair. Interestingly, the amount of DNA repair increases at 10-50 rads, plateaus, and then increases even further at higher doses well below doses where radiation-induced lethality

89

An evaluation of theories concerning the health effects of low-dose radiation exposures  

E-Print Network (OSTI)

The danger of high, acute doses of radiation is well documented, but the effects of low-dose radiation below 100 mSv is still heavily debated. Four theories concerning the effects of lowdose radiation are presented here: ...

Wei, Elizabeth J. (Elizabeth Jay)

2012-01-01T23:59:59.000Z

90

Radiation-Induced Effects on Microstructure  

Science Conference Proceedings (OSTI)

Irradiation of materials with particles that are sufficiently energetic to create atomic displacements can induce significant microstructural alteration, ranging from crystalline-to-amorphous phase transitions to the generation of large concentrations of point defect or solute aggregates in crystalline lattices. These microstructural changes typically cause significant changes in the physical and mechanical properties of the irradiated material. A variety of advanced microstructural characterization tools are available to examine the microstructural changes induced by particle irradiation, including electron microscopy, atom probe field ion microscopy, X-ray scattering and spectrometry, Rutherford backscattering spectrometry, nuclear reaction analysis, and neutron scattering and spectrometry. Numerous reviews, which summarize the microstructural changes in materials associated with electron and heavy ion or neutron irradiation, have been published. These reviews have focused on pure metals as well as model alloys, steels, and ceramic materials. In this chapter, the commonly observed defect cluster morphologies produced by particle irradiation are summarized and an overview is presented on some of the key physical parameters that have a major influence on microstructural evolution of irradiated materials. The relationship between microstructural changes and evolution of physical and mechanical properties is then summarized, with particular emphasis on eight key radiation-induced property degradation phenomena. Typical examples of irradiated microstructures of metals and ceramic materials are presented. Radiation-induced changes in the microstructure of organic materials such as polymers are not discussed in this overview.

Zinkle, Steven J [ORNL

2012-01-01T23:59:59.000Z

91

RADIATION EFFECTS ON EPOXY/CARBON FIBER COMPOSITE  

SciTech Connect

The Department of Energy Savannah River Site vitrifies nuclear waste incident to defense programs through its Defense Waste Processing Facility (DWPF). The piping in the DWPF seal pot jumper configuration must withstand the stresses during an unlikely but potential deflagration event, and maintain its safety function for a 20-year service life. Carbon fiber-reinforced epoxy composites (CFR) were proposed for protection and reinforcement of piping during such an event. The proposed CFR materials have been ASME-approved (Section XI, Code Case N-589-1) for post-construction maintenance and is DOT-compliant per 49CFR 192 and 195. The proposed carbon fiber/epoxy composite reinforcement system was originally developed for pipeline rehabilitation and post-construction maintenance in petrochemical, refineries, DOT applications and other industries. The effects of ionizing radiation on polymers and organic materials have been studied for many years. The majority of available data are based on traditional exposures to gamma irradiation at high dose rates ({approx}10,000 Gy/hr) allowing high total dose within reasonable test periods and general comparison of different materials exposed at such conditions. However, studies in recent years have shown that degradation of many polymers are sensitive to dose rate, with more severe degradation often observed at similar or even lower total doses when exposed to lower dose rates. This behavior has been primarily attributed to diffusion-limited oxidation which is minimized during very high dose rate exposures. Most test standards for accelerated aging and nuclear qualification of components acknowledge these limitations. The results of testing to determine the radiation resistance and microstructural effects of gamma irradiation exposure on a bisphenol-A based epoxy matrix composite reinforced with carbon fibers are presented. This work provides a foundation for a more extensive evaluation of dose rate effects on advanced epoxy reinforced composites.

Hoffman, E; Eric Skidmore, E

2008-12-12T23:59:59.000Z

92

RADIATION EFFECTS ON EPOXY CARBON FIBER COMPOSITE  

SciTech Connect

Carbon fiber-reinforced bisphenol-A epoxy matrix composite was evaluated for gamma radiation resistance. The composite was exposed to total gamma doses of 50, 100, and 200 Mrad. Irradiated and baseline samples were tested for tensile strength, hardness and evaluated using FTIR (Fourier transform infrared) spectroscopy and DSC (differential scanning calorimetry) for structural changes. Scanning electron microscopy was used to evaluate microstructural behavior. Mechanical testing of the composite bars revealed no apparent change in modulus, strain to failure, or fracture strength after exposures. However, testing of only the epoxy matrix revealed changes in hardness, thermal properties, and FTIR results with increasing gamma irradiation. The results suggest the epoxy within the composite can be affected by exposure to gamma irradiation.

Hoffman, E

2008-05-30T23:59:59.000Z

93

Low Dose Radiation Exposure: Exploring Bystander Effects In Vivo.  

NLE Websites -- All DOE Office Websites (Extended Search)

Exposure: Exploring Bystander Effects Exposure: Exploring Bystander Effects In Vivo. 1 Blyth, B.J., 1 Sykes, P.J. 1 Department of Haematology and Genetic Pathology, Flinders University and Medical Centre, Bedford Park, South Australia, 5042, The general population is daily exposed to chronic, low doses of ionizing radiation from both natural and artificial sources. The shape of the radiation dose-response curve at these low doses is currently linearly extrapolated from data obtained after high dose exposure due to the low sensitivity of traditional biological assays after near-background exposures. At odds with this Linear No-Threshold model, are the phenomena collectively referred to as the radiation-induced bystander effect. The bystander effect describes a collection of in vitro

94

Radiation Damage Studies with Hadrons on Materials and Electronics  

E-Print Network (OSTI)

SLAC-PUB-10534 July 2004 Radiation Damage Studies withJ. Spencer. , Z. Wolf, SLAC, Menlo Park, CA 94025, USA M.J. Spencer ? Z. Wolf, SLAC, Menlo Park, CA 94025, USA M.

2004-01-01T23:59:59.000Z

95

A Solar Radiation Model for Use in Climate Studies  

Science Conference Proceedings (OSTI)

A solar radiation routine has been developed for use in climate studies. It includes the absorption and scattering due to ozone, water vapor, oxygen, carbon dioxide, clouds, and aerosols. Rayleigh scattering is also included. The UV and visible ...

Ming-Dah Chou

1992-05-01T23:59:59.000Z

96

Effect of distance to radiation treatment facility on use of radiation therapy after mastectomy in elderly women  

Science Conference Proceedings (OSTI)

Purpose: We sought to study the effect of distance to the nearest radiation treatment facility on the use of postmastectomy radiation therapy (PMRT) in elderly women. Methods and Materials: Using data from the linked Surveillance, Epidemiology, and End Results-Medicare (SEER-Medicare) database, we analyzed 19,787 women with Stage I or II breast cancer who received mastectomy as definitive surgery during 1991 to 1999. Multivariable logistic regression was used to investigate the association of distance with receipt of PMRT after adjusting for clinical and sociodemographic factors. Results: Overall 2,075 patients (10.5%) treated with mastectomy received PMRT. In addition to cancer and patient characteristics, in our primary analysis, increasing distance to the nearest radiation treatment facility was independently associated with a decreased likelihood of receiving PMRT (OR 0.996 per additional mile, p = 0.01). Secondary analyses revealed that the decline in PMRT use appeared at distances of more than 25 miles and was statistically significant for those patients living more than 75 miles from the nearest radiation facility (odds of receiving PMRT of 0.58 [95% CI 0.34-0.99] vs. living within 25 miles of such a facility). The effect of distance on PMRT appeared to be more pronounced with increasing patient age (>75 years). Variation in the effect of distance on radiation use between regions of the country and nodal status was also identified. Conclusions: Oncologists must be cognizant of the potential barrier to quality care that is posed by travel distance, especially for elderly patients; and policy makers should consider this fact in resource allocation decisions about radiation treatment centers.

Punglia, Rinaa S. [Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, MA (United States)]. E-mail: rpunglia@lroc.harvard.edu; Weeks, Jane C. [Division of Medical Oncology, Center for Outcomes and Policy Research, Dana-Farber Cancer Institute, Boston, MA (United States); Neville, Bridget A. [Division of Medical Oncology, Center for Outcomes and Policy Research, Dana-Farber Cancer Institute, Boston, MA (United States); Earle, Craig C. [Division of Medical Oncology, Center for Outcomes and Policy Research, Dana-Farber Cancer Institute, Boston, MA (United States)

2006-09-01T23:59:59.000Z

97

Heat pipe radiation cooling evaluation: Task 2 concept studies report  

SciTech Connect

This report presents the result of Task 2, Concept Studies for Heat Pipe Radiation Cooling (HPRC), which was performed for Los Alamos National Laboratory under Contract 9-XT1-U9567. Studies under a prior contract defined a reference HPRC conceptual design for hypersonic aircraft engines operating at Mach 5 and an altitude of 80,000 ft. Task 2 involves the further investigation of heat pipe radiation cooling (HPRC) systems for additional design and operating conditions.

Silverstein, C.C.

1991-10-01T23:59:59.000Z

98

Low Dose Radiation Research Program: Transgenerational Effects...  

NLE Websites -- All DOE Office Websites (Extended Search)

Transgenerational Effects of Chronic Low-Dose Irradiation in a Medaka Fish Model System Colorado State University Why this Project? There are major gaps in our knowledge about...

99

Effective dose and several factors of its identification. (Assessment of radiation hazard in space flights)  

E-Print Network (OSTI)

Effective dose and several factors of its identification. (Assessment of radiation hazard in space flights)

Farber, Yu V; Grigoriev, Yu G; Tabakova, L A

1971-01-01T23:59:59.000Z

100

The Effects of Radiation on Development of Prostate Cancer and Prostatic  

NLE Websites -- All DOE Office Websites (Extended Search)

Effects of Radiation on Development of Prostate Cancer and Prostatic Effects of Radiation on Development of Prostate Cancer and Prostatic Hyperplasia in Canine Model Gayle Woloschak Northwestern University Abstract Purpose/Objective(s): There have been few studies analyzing radiation-induced prostate cancer in humans or animals. Our research attempts to fill this void by determining the effects of cobalt-60 gamma radiation on the incidence of prostate cancer and prostatic hyperplasia in a large cohort of beagle dogs. Material/Methods: The subjects for the experiment were beagle dogs, which were chosen due to physiologic and anatomic similarities to humans (Thompson, 1989). We retrospectively analyzed data from historic irradiation experiments conducted at Argonne National Laboratory on 347 beagles. The cobalt-60 cohort consisted of 268 dogs, which received whole

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Clear Skies A Study of Longwave Radiation Codes for Climate Studies...  

NLE Websites -- All DOE Office Websites (Extended Search)

Study of Longwave Radiation Codes for Climate Studies: Validation with Observations and Tests in General Circulation Models-an Update R. G. Ellingson and F. Baer Department of...

102

Low Dose Radiation Research Program: Effects of Low Doses of Radiation on  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Doses of Radiation on DNA Repair Low Doses of Radiation on DNA Repair Eric Ackerman Pacific Northwest National Laboratory Why this Project? Even low doses (0.1 Gy) exert measurable effects on DNA repair. The first-known oxidative lesion repaired only by nucleotide excision repair found in normal cells is cyclo-dA. This lesion is found in normal cells and thought to be a byproduct of oxidative metabolism. When this lesion occurs, it stimulates repair. If repair is stimulated by low dose radiation, there are some implications for human health. For example, do some individuals exhibit a greater, lower, or no stimulation to certain DNA lesions? If there are population polymorphism that influence DNA repair, then it would be possible to use our assay for screening individuals for repair sensitivity.

103

EPIDEMIOLOGICAL STUDIES ON RADIATION CARCINOGENESIS IN HUMAN POPULATIONS FOLLOWING ACUTE EXPOSURE: NUCLEAR EXPLOSIONS AND MEDICAL RADIATION  

E-Print Network (OSTI)

of the Current State of Radiation Protection Philosophy.Against Pergamon Ionizing Radiation from External Sources,for Protection Against Ionizing Radiation from Supplement to

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

104

Radiation Effects on the Cytoskeleton of Endothelial Cells and Endothelial Monolayer Permeability  

Science Conference Proceedings (OSTI)

Purpose: To investigate the effects of radiation on the endothelial cytoskeleton and endothelial monolayer permeability and to evaluate associated signaling pathways, which could reveal potential mechanisms of known vascular effects of radiation. Methods and Materials: Cultured endothelial cells were X-ray irradiated, and actin filaments, microtubules, intermediate filaments, and vascular endothelial (VE)-cadherin junctions were examined by immunofluorescence. Permeability was determined by the passage of fluorescent dextran through cell monolayers. Signal transduction pathways were analyzed using RhoA, Rho kinase, and stress-activated protein kinase-p38 (SAPK2/p38) inhibitors by guanosine triphosphate-RhoA activation assay and transfection with RhoAT19N. The levels of junction protein expression and phosphorylation of myosin light chain and SAPK2/p38 were assessed by Western blotting. The radiation effects on cell death were verified by clonogenic assays. Results: Radiation induced rapid and persistent actin stress fiber formation and redistribution of VE-cadherin junctions in microvascular, but not umbilical vein endothelial cells, and microtubules and intermediate filaments remained unaffected. Radiation also caused a rapid and persistent increase in microvascular permeability. RhoA-guanosine triphosphatase and Rho kinase were activated by radiation and caused phosphorylation of downstream myosin light chain and the observed cytoskeletal and permeability changes. SAPK2/p38 was activated by radiation but did not influence either the cytoskeleton or permeability. Conclusion: This study is the first to show rapid activation of the RhoA/Rho kinase by radiation in endothelial cells and has demonstrated a link between this pathway and cytoskeletal remodeling and permeability. The results also suggest that the RhoA pathway might be a useful target for modulating the permeability and other effects of radiation for therapeutic gain.

Gabrys, Dorota [Department of Radiation Oncology, Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Gliwice (Poland); Greco, Olga [Cancer Research UK Tumour Microcirculation Group, Academic Unit of Surgical Oncology, University of Sheffield, School of Medicine and Biomedical Sciences, Sheffield (United Kingdom); Patel, Gaurang; Prise, Kevin M. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Tozer, Gillian M. [Cancer Research UK Tumour Microcirculation Group, Academic Unit of Surgical Oncology, University of Sheffield, School of Medicine and Biomedical Sciences, Sheffield (United Kingdom); Kanthou, Chryso [Cancer Research UK Tumour Microcirculation Group, Academic Unit of Surgical Oncology, University of Sheffield, School of Medicine and Biomedical Sciences, Sheffield (United Kingdom)], E-mail: C.Kanthou@sheffield.ac.uk

2007-12-01T23:59:59.000Z

105

Effects of Atmospheric Absorption of Incoming Radiation on the Radiation Limit of the Troposphere  

Science Conference Proceedings (OSTI)

The limit of the planetary radiation (longwave radiation) of a planet with oceans on its surface is determined by various mechanisms called “radiation limits,” which can be classified as the Komabayashi–Ingersoll limit and the radiation limit of ...

Hiroyuki Kurokawa; Taishi Nakamoto

2012-01-01T23:59:59.000Z

106

THE COMBINED EFFECT OF RADIATION AND CHEMICAL CARCINOGENS IN FEMALE A x IF MICE  

E-Print Network (OSTI)

Summary.-Groups of mice were exposed to various doses of ionizing radiation on one occasion. In two groups of animals the bladder carcinogens dibutylnitrosamine (DBNA) and 4-ethylsulphonyl-naphthalene-1-sulphonamide (ENS) were administered 48 hours after irradiation. Post mortem and histopathological examinations failed to show any significant lesion in the bladder of animals subjected to radiation per se. Furthermore, radiation did not influence the latent period or incidence of bladder tumours induced by DBNA and ENS. However, radiation shortened the latent period of mammary tumours and, in some groups, increased the incidence of such lesions. When radiation was combined with the chemical carcinogens there was a marked reduction in the incidence of mammary tumours. VARIOUS authors have shown that ionizing radiation, whether by accident or by intention, has been responsible for the induction of tumours (British Medical Bulletin, 1973). The present study was designed to examine firstly the acute and long-term effects of a single dose of ionizing radiation on the bladder and secondly the influence of radiation on the latent period and incidence of bladder tumours caused by two known bladder carcinogens, dibutylnitrosamine (DBNA) and 4-ethylsulphonylnaphthalene- 1- sulphonamide (ENS). DBNA has been reported to induce bladder tumours in the rat (Druckrey et al., 1962, 1964) and in the mouse

A. Flaks; J. M. Hamilton; D. B. Clayson; P. R. J. Burch

1973-01-01T23:59:59.000Z

107

Radioprotective Effect of Lidocaine on Function and Ultrastructure of Salivary Glands Receiving Fractionated Radiation  

Science Conference Proceedings (OSTI)

Purpose: Radiation-induced xerostomia still represents a common side effect after radiotherapy for head-and-neck malignancies. The aim of the present study was to examine the radioprotective effect of lidocaine hydrochloride during fractionated radiation in an experimental animal model. Methods and Materials: To evaluate the influence of different radiation doses on salivary gland function and the radioprotective effect of lidocaine, rabbits were irradiated with 15, 25, 30, and 35 Gy (equivalent doses in 2-Gy fractions equivalent to 24, 40, 48, and 56 Gy, respectively). Lidocaine hydrochloride (10 and 12 mg/kg) was administered before every radiation fraction in the treatment groups. Salivary gland function was assessed by flow sialometry and sialoscintigraphy, and the morphologic changes were evaluated using transmission electron microscopy. Results: Functional impairment was first observed after 35 Gy and pretreatment with lidocaine improved radiation tolerance of both parotid and submandibular glands. The use of 12 mg/kg lidocaine was superior and displayed significant radioprotection with regard to flow sialometry and sialoscintigraphy. The ultrastructure was largely preserved after pretreatment with both lidocaine doses. Conclusions: Lidocaine represents an effective radioprotective agent and a promising approach for clinical application to avoid radiation-induced functional impairment of salivary glands.

Hakim, Samer George, E-mail: samer.hakim@mkg-chir.mu-luebeck.de [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Benedek, Geza Attila [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Su Yuxiong [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Department of Oral and Maxillofacial Surgery, Sun Yat-Sen University, Guanghua School of Stomatology, Guanghua (China); Jacobsen, Hans Christian [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Klinger, Matthias [Institute of Anatomy, University of Luebeck, Luebeck (Germany); Dendorfer, Andreas [Institute of Experimental and Clinical Pharmacology and Toxicology, University of Luebeck, Luebeck (Germany); Hemmelmann, Claudia [Institute of Medical Biometry and Statistics, University of Luebeck, Luebeck (Germany); Meller, Birgit [Department of Radiology and Nuclear Medicine, University of Luebeck, Luebeck (Germany); Nadrowitz, Roger; Rades, Dirk [Department of Radiation Oncology, University of Luebeck, Luebeck (Germany); Sieg, Peter [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany)

2012-03-15T23:59:59.000Z

108

Low Dose Radiation Research Program: Characterizing Bystander Effects  

NLE Websites -- All DOE Office Websites (Extended Search)

Irradiation. Irradiation. Authors: L.A. Braby and J.R. Ford. Institutions: Texas A&M University. Bystander effects, which are typically seen as in increase in the cellular concentration of specific repair related molecules or as cytogenetic changes which appear to be the consequence of DNA damage, may be a significant factor in the risk of long-term health effects of low doses of radiation. These effects clearly increase the effective size of the target for radiation response, from the diameter of a single cell or cell nucleus to something significantly larger, by bringing additional cells into the process. It is unclear whether this larger target will result in an increase or a decrease in the probability of inducing a change which would be detrimental to the health of the organism, but it clearly reduces the

109

Total aerosol effect: forcing or radiative flux perturbation?  

Science Conference Proceedings (OSTI)

Uncertainties in aerosol forcings, especially those associated with clouds, contribute to a large extent to uncertainties in the total anthropogenic forcing. The interaction of aerosols with clouds and radiation introduces feedbacks which can affect the rate of rain formation. Traditionally these feedbacks were not included in estimates of total aerosol forcing. Here we argue that they should be included because these feedbacks act quickly compared with the time scale of global warming. We show that for different forcing agents (aerosols and greenhouse gases) the radiative forcings as traditionally defined agree rather well with estimates from a method, here referred to as radiative flux perturbations (RFP), that takes these fast feedbacks and interactions into account. Thus we propose replacing the direct and indirect aerosol forcing in the IPCC forcing chart with RFP estimates. This implies that it is better to evaluate the total anthropogenic aerosol effect as a whole.

Lohmann, Ulrike; Storelvmo, Trude; Jones, Andy; Rotstayn, Leon; Menon, Surabi; Quaas, Johannes; Ekman, Annica; Koch, Dorothy; Ruedy, Reto

2009-09-25T23:59:59.000Z

110

Preliminary Studies on the Variational Assimilation of Cloud-Radiation Observations Using ARM Observations  

NLE Websites -- All DOE Office Websites (Extended Search)

Studies on the Variational Assimilation Studies on the Variational Assimilation of Cloud-Radiation Observations Using ARM Observations M. Janisková, J.-F. Mahfouf, and J.-J. Morcrette European Centre for Medium-Range Weather Forecasts Shinfield Park, Reading Berskshire, United Kingdom Abstract A linearized cloud scheme and a radiation scheme including cloud effects have been developed at European Centre for Medium-Range Weather Forecasts (ECMWF) to assimilate cloud properties in the framework of the four-dimensional variational (4D-Var) assimilation system. To investigate the potential of those schemes to modify the model temperature, humidity and cloud profiles and produce a better match to the observed radiation fluxes, one-dimensional variational (1D-Var) assimilation experiments have been carried out using data from the Atmospheric Radiation Measurement (ARM)

111

Consideration of Dynamical Effects on Parameterization of Clooud radiative Properties  

NLE Websites -- All DOE Office Websites (Extended Search)

Consideration of Dynamical Effects on Consideration of Dynamical Effects on Parameterization of Cloud Radiative Properties P. H. Daum and Y. Liu Environmental Sciences Department Brookhaven National Laboratory Upton, New York Introduction Effective radius (r e ) (defined as the ratio of the third to the second moment of a droplet size distribution) is one of the key variables that are used for calculation of the radiative properties of liquid water clouds (Hansen and Travis 1974). The inclusion and parameterization of r e in climate models has proven to be critical for assessing global climate change (Slingo 1990, Dandin et al. 1997). It has been demonstrated empirically (Pontikis and Hicks 1992, Bower and Choularton 1992, Bower et al. 1994, Martin et al. 1994, Liu and Hallett 1997, Reid et al. 1998, Liu and Daum 2000a), as well theoretically (Liu and

112

Coastal-inland solar radiation difference study. Final report  

DOE Green Energy (OSTI)

The purpose of this study was to quantify the characteristics of solar insolation in the coastal zone and to determine the effect of the sea breeze circulation on the global insolation. In order to satisfy these objectives, a six station sampling network was established in the coastal plain of southeastern North Carolina, where previous evidence has indicated that the sea breeze circulation is almost a daily occurrence from late May through October. Three sites (Sloop Point, Onslow Beach, and Cape Fear Technical Institute (CFTI)) were located near the coast (coastal sites) to assess the insolation at the coast. A site (Clinton) was located in an area seldom affected by the sea breeze (about 100 km from the coast). Two additional sites, Wallace and Ellis Airport, located between the coastal sites and the control site, were to be used to assess the transient impact of the sea breeze upon the insolation. Pyranometers were located at each site to measure the global insolation. Direct normal insolation measured by a pyrheliometer and ultraviolet radiation measured by uv radiometers were observed at the Sloop Point and Clinton sites only. Data were collected during the calendar year 1978. The results of the study indicated that the global insolation had greater variability over the network during the summer season (June, July, and August). During the summer, there was a systematicdiurnal variation of the difference in global insolation between the inland and the coastal sites.

Bach, W.D. Jr.; Vukovich, F.M.

1980-04-01T23:59:59.000Z

113

An Indirect Effect of Ice Nuclei on Atmospheric Radiation  

Science Conference Proceedings (OSTI)

A three-dimensional cloud-resolving model (CRM) with observed large-scale forcing is used to study how ice nuclei (IN) affect the net radiative flux at the top of the atmosphere (TOA). In all the numerical experiments carried out, the cloud ice ...

Xiping Zeng; Wei-Kuo Tao; Minghua Zhang; Arthur Y. Hou; Shaocheng Xie; Stephen Lang; Xiaowen Li; David O’C. Starr; Xiaofan Li; Joanne Simpson

2009-01-01T23:59:59.000Z

114

Effects of Aerosols on the Radiative Properties of Clouds  

Science Conference Proceedings (OSTI)

The influence of anthropogenic aerosols, in the form of ship exhaust effluent, on the microphysics and radiative properties of marine stratocumulus is studied using data gathered from the U.K. Met. Office C-130 and the University of Washington C-...

Jonathan P. Taylor; Martin D. Glew; James A. Coakley Jr.; William R. Tahnk; Steven Platnick; Peter V. Hobbs; Ronald J. Ferek

2000-08-01T23:59:59.000Z

115

Technical Sessions A Study of Longwave Radiation Codes for Climate Studies:  

NLE Websites -- All DOE Office Websites (Extended Search)

A Study of Longwave Radiation A Study of Longwave Radiation Codes for Climate Studies: Validation with ARM Observations and Tests in General Circulation Models R. G. Ellingson F. Baer Department of Meteorology University of Maryland College Park, MD 20742 Introduction the radiation sensitivity problem. We anticipate that the outcome of this approach will provide both a better longwave radiative forcing algorithm and a better understanding of how longwave radiative forcing influences the equilibrium climate of the atmosphere. Nature of Longwave Problems Longwave radiation quantities-radiances, fluxes and heating rates-are usually calculated in GCM models as the cloud amount weighted average of the values for clear and homogeneous cloud conditions. For example, the downward flux at the surface, F, may be written as

116

Tail terms in gravitational radiation reaction via effective field theory  

E-Print Network (OSTI)

Gravitational radiation reaction affects the dynamics of gravitationally bound binary systems. Here we focus on the leading "tail" term which modifies binary dynamics at fourth post-Newtonian order, as first computed by Blanchet and Damour. We re-produce this result using effective field theory techniques in the framework of the Lagrangian formalism suitably extended to include dissipation effects. We recover the known logarithmic tail term, consistently with the recent interpretation of the logarithmic tail term in the mass parameter as a renormalization group effect of the Bondi mass of the system.

S. Foffa; R. Sturani

2011-11-23T23:59:59.000Z

117

Fog-82: A Cooperative Field Study of Radiation Fog  

Science Conference Proceedings (OSTI)

The Cloud Physics Section of the Atmospheric Sciences Research Center-State University of New York at Albany conducted a cooperative field study (FOG-82) during the autumn of 1982 as part of an ongoing radiation-fog research program. A computer-...

Michael B. Meyer; G. Garland Lala; James E. Jiusto

1986-07-01T23:59:59.000Z

118

Investigation of non-targeted effects of low dose ionizing radiation on the mammary gland  

NLE Websites -- All DOE Office Websites (Extended Search)

non-targeted effects of low dose ionizing radiation on the mammary gland non-targeted effects of low dose ionizing radiation on the mammary gland utilizing three-dimensional culture models of mammary cells derived from mouse strains that differ in susceptibility to tumorigenesis Joni D. Mott, Antoine M. Snijders, Alvin Lo, Dinah Levy-Groesser, Bahram Parvin, Andrew J. Wyrobek, Jian-Hua Mao, and Mina J. Bissell Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley CA 94720 Goal: Within the Lawrence Berkeley National Laboratory's SFA, Project 2, our studies focus on utilizing three dimensional (3D) cell culture models as surrogates for in vivo studies to determine how low doses of ionizing radiation influence mammary gland tissue architecture and how this may relate both to tumor progression and/or adaptive response.

119

Use of In Situ Observations to Characterize Cloud Microphysical and Radiative Properties: Application to Climate Studies  

NLE Websites -- All DOE Office Websites (Extended Search)

Use of In Situ Observations to Characterize Use of In Situ Observations to Characterize Cloud Microphysical and Radiative Properties: Application to Climate Studies G. M. McFarquhar and T. Nousiainen Department of Atmospheric Sciences University of Illinois Urbana, Illinois M. S. Timlin, S. F. Iacobellis, and R. C. J. Somerville Scripps Institution of Oceanography La Jolla, California Introduction Cloud radiative feedback is the most important effect determining climate response to human activity. Ice clouds reflect solar radiation and absorb thermal emission from the ground and the lower atmosphere and emit infrared radiation to space. The representation of these processes in models affects future climate predictions and there is much uncertainty in the representation of these processes. The size and

120

THE EFFECT OF CIRCUMSOLAR RADIATION ON THE ACCURACY OF PYRHELIOMETER MEASUREMENTS OF THE DIRECT SOLAR RADIATION  

E-Print Network (OSTI)

Diffuse, and Total Solar Radiation," Solar Energy, vol. 4,r Presented at the Solar Radiation workshop of Solar Rising,MEASUREMENTS OF THE DIRECT SOLAR RADIATION D. Grether, D.

Grether, D.

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Interactions between Vegetation and Climate: Radiative and Physiological Effects of Doubled Atmospheric CO2  

Science Conference Proceedings (OSTI)

The radiative and physiological effects of doubled atmospheric carbon dioxide (CO2) on climate are investigated using a coupled biosphere–atmosphere model. Five 30-yr climate simulations, designed to assess the radiative and physiological effects ...

L. Bounoua; G. J. Collatz; P. J. Sellers; D. A. Randall; D. A. Dazlich; S. O. Los; J. A. Berry; I. Fung; C. J. Tucker; C. B. Field; T. G. Jensen

1999-02-01T23:59:59.000Z

122

Effect of Ice-Albedo Feedback on Global Sensitivity in a One-Dimensional Radiative-Convective Climate Model  

Science Conference Proceedings (OSTI)

The feedback between ice albedo and temperature is included in a one-dimensional radiative-convective climate model. The effect of this feedback on global sensitivity to changes in solar constant is studied for the current climate conditions. ...

Wei-Chyung Wang; Peter H. Stone

1980-03-01T23:59:59.000Z

123

Determination of the Optical Thickness and Effective Particle Radius of Clouds from Reflected Solar Radiation Measurements. Part I: Theory  

Science Conference Proceedings (OSTI)

A method is presented for determining the optical thickness and effective particle radius of stratiform cloud layers from reflected solar radiation measurements. A detailed study is presented which shows that the cloud optical thickness (?c) and ...

Teruyuki Nakajima; Michael D. King

1990-08-01T23:59:59.000Z

124

The In-Orbit Radiation Environment and Its Effects on Space-Borne Instrumentation  

E-Print Network (OSTI)

An overview is given on the various components of the radiation environment of the ISO mission, including cosmic rays, geomagnetically trapped protons and electrons, and the solar proton events. Various aspects related to the radiation shielding and to the radiation-induced effects on instrumentation will also be discussed. For the benefit of future missions, relevant lessons learned concerning ISO radiation environment and its effects will finally be summarised. Key words: ISO, space radiation -- macros: L A T E X 1.

P. Nieminen

2001-01-01T23:59:59.000Z

125

Review and Evaluation of Updated Research on the Health Effects Associated with Low-Dose Ionizing Radiation  

Science Conference Proceedings (OSTI)

Potential health effects of low levels of radiation have predominantly been based on those effects observed at high levels of radiation. The authors have reviewed more than 200 percent publications in radiobiology and epidermiology related to low dose radiation and concluded that recent radiobiological studies at low-doses; that doses low dose radiation research should to holistic, systems-based approaches to develop models that define the shape of the dose-response relationships at low doses; and that these results should be combined with the latest epidermiology to produce a comprehensive understanding of radiation effects that addresses both damage, likely with a linear effect, and response, possibly with non-linear consequences.

Dauer, Lawrence T.; Brooks, Antone L.; Hoel, David G.; Morgan, William F.; Stram, Daniel; Tran, Phung

2010-07-01T23:59:59.000Z

126

Space Radiation Effects on Er-Doped, Yb-Doped and Yb/Er Co ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2012. Symposium, Glass and Optical Materials. Presentation Title, Space Radiation Effects on ...

127

Effects of gonadal irradiation in clinical radiation therapy: a review  

SciTech Connect

Recent improvements in radiation therapy of some malignancies in lower abdominal sites are leading to prolongation of life in persons of child-bearing age. These successes require an evaluation of the possible undesirable consequences of the unavoidable gonadal irradiation that occurs in these cases. A review of radiobiological data from experimental animal studies and retrospective clinical studies suggests that in most instances human gonadal exposures in both sexes are insufficient to cause permanent sterility, because the exposures are fractionated and the total gonadal dose is much less than 600 rads. As a consequence, return of fertility must be anticipated, and the worrisome questions of radiation-induced genetic damage in subsequent pregnancies must be addressed. This review did not substantiate this fear, because no case reports could be found of malformed infants among the progency of previously irradiated parents. Some experimental studies suggest that radiation-damaged spermatogonia are self-destructive, but any evidence for this phenomenon in the ovary is nonexistent. We suggest that the difference between fact and theory here may be the mathematical result of the interplay of low probability for occurrences and the few patients who until now have survived long enough for study. (auth)

Lushbaugh, C.C.; Casarett, G.W.

1976-02-01T23:59:59.000Z

128

Radiation effects in space: The Clementine I mission  

SciTech Connect

The space radiation environment for the CLEMENTINE I mission was investigated using a new calculational model, CHIME, which includes the effects of galactic cosmic rays (GCR), anomalous component (AC) species and solar energetic particle (SEP) events and their variations as a function of time. Unlike most previous radiation environment models, CHIME is based upon physical theory and is {open_quotes}calibrated{close_quotes} with energetic particle measurements made over the last two decades. Thus, CHIME provides an advance in the accuracy of estimating the interplanetary radiation environment. Using this model we have calculated particle energy spectra, fluences and linear energy transfer (LET) spectra for all three major components of the CLEMENTINE I mission during 1994: (1) the spacecraft in lunar orbit, (2) the spacecraft during asteroid flyby, and (3) the interstate adapter USA in Earth orbit. Our investigations indicate that during 1994 the level of solar modulation, which dominates the variation in the GCR and AC flux as a function of time, will be decreasing toward solar minimum levels. Consequently the GCR and AC flux will be increasing during Y, the year and, potentially, will rise to levels seen during previous solar minimums. The estimated radiation environment also indicates that the AC will dominate the energetic particle spectra for energies below 30-50 MeV/nucleon, while the GCR have a peak flux at {approximately}300 MeV/nucleon and maintain a relatively high flux level up to >1000 MeV/nucleon. The AC significantly enhances the integrated flux for LET in the range 1 to 10 MeV/(mg/cm{sup 2}), but due to the steep energy spectra of the AC a relatively small amount of material ({approximately}50 mils of Al) can effectively shield against this component. The GCR are seen to be highly penetrating and require massive amounts of shielding before there is any appreciable decrease in the LET flux.

Guzik, T.G.; Clayton, E.; Wefel, J.P.

1994-12-20T23:59:59.000Z

129

A Theoretical Study of the Magnetic Structure of Bulk Iron with Radiation Defects  

SciTech Connect

A fundamental understanding of the radiation damage effects in solids is of great importance in assisting the development of improved materials with ultra-high strength, toughness, and radiation resistance for nuclear energy applications. In this presentation, we show our recent theoretical investigation on the magnetic structure evolution of bulk iron in the region surrounding the radiation defects. We applied the locally self-consistent multiple scattering method (LSMS), a linear scaling ab-initio method based on density functional theory with local spin density approximation, to the study of the magnetic structure in a low energy cascade in a 10,000-atom sample for a series of time steps for the evolution of the defects. The primary damage state and the evolution of all defects in the sample were simulated using molecular dynamics with empirical, embedded-atom inter-atomic potentials. We also discuss the importance of thermal effect on the magnetic structure evolution.

Wang, Yang [Pittsburgh Supercomputing Center; Stoller, Roger E [ORNL; Rusanu, Aurelian [ORNL; Nicholson, Don M [ORNL; Eisenbach, Markus [ORNL; Stocks, George Malcolm [ORNL

2011-01-01T23:59:59.000Z

130

Activities of the National Academy of Sciences in relation to the Radiation Effects Research Foundation  

Science Conference Proceedings (OSTI)

The activities of the National Academy of Sciences (NAS), in relation to the Radiation Effects Research Foundation (RERF), has a long history and the specific time period supported by this contract is but a small piece of the long-term continuing program. As a background, in August 1945, atomic bombs were dropped on Hiroshima (6 August) and Nagasaki (9 August). Shortly after the bombings, US medical teams joined forces with their Japanese counterparts to form a Joint Commission for the Investigation of the Effects of the Atomic Bombs. As a result of the Joint Commission's investigations, it was determined that consideration should be given to the establishment of a long-term study of the potential late health effects of exposure of the survivors to radiation from the bombs. The results obtained from RERF studies contribute the vast majority of information that provides a better understanding of radiation effects on humans. This information has been used extensively by national organizations and international committees for estimating risks associated with radiation exposures. The estimated risks developed by these independent organizations are used by government agencies around the world to establish standards for protection of individuals exposed in the occupational, medical, and general environment. Some of these results are described briefly in this report.

Edington, C.W.

1991-02-01T23:59:59.000Z

131

Direct and Indirect Shortwave Radiative Effects of Sea Salt Aerosols  

Science Conference Proceedings (OSTI)

Sea salt aerosols play a dual role in affecting the atmospheric radiative balance. Directly, sea salt particles scatter the incoming solar radiation and absorb the outgoing terrestrial radiation. By acting as cloud condensation nuclei, sea salt ...

Tarek Ayash; Sunling Gong; Charles Q. Jia

2008-07-01T23:59:59.000Z

132

Pretreatment Predictors of Adverse Radiation Effects After Radiosurgery for Arteriovenous Malformation  

SciTech Connect

Purpose: To identify vascular and dosimetric predictors of symptomatic T2 signal change and adverse radiation effects after radiosurgery for arteriovenous malformation, in order to define and validate preexisting risk models. Methods and Materials: A total of 125 patients with arteriovenous malformations (AVM) were treated at our institution between 2005 and 2009. Eighty-five patients have at least 12 months of clinical and radiological follow-up. Any new-onset headaches, new or worsening seizures, or neurological deficit were considered adverse events. Follow-up magnetic resonance images were assessed for new onset T2 signal change and the volume calculated. Pretreatment characteristics and dosimetric variables were analyzed to identify predictors of adverse radiation effects. Results: There were 19 children and 66 adults in the study cohort, with a mean age of 34 (range 6-74). Twenty-three (27%) patients suffered adverse radiation effects (ARE), 9 patients with permanent neurological deficit (10.6%). Of these, 5 developed fixed visual field deficits. Target volume and 12 Gy volume were the most significant predictors of adverse radiation effects on univariate analysis (p < 0.001). Location and cortical eloquence were not significantly associated with the development of adverse events (p = 0.12). No additional vascular parameters were identified as predictive of ARE. There was a significant target volume threshold of 4 cm{sup 3}, above which the rate of ARE increased dramatically. Multivariate analysis target volume and the absence of prior hemorrhage are the only significant predictors of ARE. The volume of T2 signal change correlates to ARE, but only target volume is predictive of a higher volume of T2 signal change. Conclusions: Target volume and the absence of prior hemorrhage is the most accurate predictor of adverse radiation effects and complications after radiosurgery for AVMs. A high percentage of permanent visual field defects in this series suggest the optic radiation is a critical radiosensitive structure.

Hayhurst, Caroline; Monsalves, Eric [Gamma Knife Unit, Division of Neurosurgery, University Health Network, Toronto (Canada); Prooijen, Monique van [Physics Department, Princess Margaret Hospital, Toronto (Canada); Cusimano, Michael [Division of Neurosurgery, St Michael's Hospital, Toronto (Canada); Tsao, May [Radiation Oncology Program, Sunnybrook Hospital, University of Toronto (Canada); Menard, Cynthia [Radiation Oncology Program, Princess Margaret Hospital, University of Toronto (Canada); Kulkarni, Abhaya V. [Division of Neurosurgery, Hospital for Sick Children, University of Toronto (Canada); Schwartz, Michael [Division of Neurosurgery, Sunnybrook Hospital, University of Toronto (Canada); Zadeh, Gelareh, E-mail: gelareh.zadeh@uhn.on.ca [Gamma Knife Unit, Division of Neurosurgery, University Health Network, Toronto (Canada)

2012-02-01T23:59:59.000Z

133

Significance of radiation effects in solid radioactive waste  

SciTech Connect

Proposed NRC criteria for disposal of high-level nuclear waste require development of waste packages to contain radionuclide for at least 1000 years, and design of repositories to prevent radionuclide release at an annual rate greater than 1 part in 100,000 of the total activity. The high-level wastes that are now temporarily stored as aqueous salts, sludges, and calcines must be converted to high-integrity solid forms that resist deterioration from radiation and other effects of long-term storage. Spent fuel may be encapsulated for similar long-term storage. Candidate waste forms beside the spent fuel elements themselves, include borosilicate and related glasses, mineral-like crystalline ceramics, concrete formulations, and metal-matrix glass or ceramic composites. these waste forms will sustain damage produced by beta-gamma radiation up to 10/sup 12/ rads, by alpha radiation up to 10/sup 19/ particles/g, by internal helium generation greater than about 0.1 atom percent, and by the atom transmutations accompanying radioactive decay. Current data indicate that under these conditions the glass forms suffer only minor volume changes, stored energy deposition, and leachability effects. The crystalline ceramics appear susceptible to the potentially more severe alterations accompanying metamictization and natural analogs of candidate materials are being examined to establish their suitability as waste forms. Helium concentrations in the waste forms are generally below thresholds for severe damage in either glass or crystalline ceramics at low temperatures, but microstructural effects are not well characterized. Transmutation effects remain to be established.

Permar, P H; McDonell, W R

1980-01-01T23:59:59.000Z

134

Human radiation studies: Remembering the early years. Oral history of Dr. George Voelz, M.D., November 29, 1994  

SciTech Connect

Dr. George Voelz was interviewed by representatives of the US DOE Office of Human Radiation Experiments (OHRE). This oral history covers Dr. Voelz`s research on Manhattan Engineering District plutonium workers, the acute and long term effects of radiation, his inhalation studies, and his activities at the 1961 INL reactor accident (SL-1 Reactor). After a brief biographical sketch, Dr. Voelz his remembrances on tissue studies of plutonium workers, the plutonium injection studies of 1945-1946, the controlled environmental radioiodine tests of 1963-1968, and tracer studies with human volunteers at Los Alamos. Dr. Voelz states his opinions concerning misconceptions about the Los Alamos Human Radiation Experiments.

1995-05-01T23:59:59.000Z

135

A Study of Radiative Bottomonium Transitions using Converted Photons  

SciTech Connect

The authors use (111 {+-} 1) million {Upsilon}(3S) and (89 {+-} 1) million {Upsilon}(2S) events recorded by the BABAR detector at the PEP-II B-factory at SLAC to perform a study of radiative transitions betwen bottomonium states using photons that have been converted to e{sup +}e{sup -} pairs by the detector material. They observe {Upsilon}(3S) {yields} {gamma}{chi}{sub b0,2}(1P) decay, make precise measurements of the branching fractions for {chi}{sub b1,2}(1P, 2P) {yields} {gamma}{Upsilon}(1S) and {chi}{sub b1,2}(2P) {yields} {gamma}{Upsilon}(2S) decays, and search for radiative decay to the {eta}{sub b}(1S) and {eta}{sub b}(2S) states.

Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Bari /Bari U.; Milanes, D.A.; /INFN, Bari; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-15T23:59:59.000Z

136

An Improved Parameterization for Estimating Effective Atmospheric Emissivity for Use in Calculating Daytime Downwelling Longwave Radiation  

Science Conference Proceedings (OSTI)

An improved parameterization is presented for estimating effective atmospheric emissivity for use in calculating downwelling longwave radiation based on temperature, humidity, pressure, and solar radiation observations. The first improvement is ...

Todd M. Crawford; Claude E. Duchon

1999-04-01T23:59:59.000Z

137

Radiative Effects of Airborne Dust on Regional Energy Budgets at the Top of the Atmosphere  

Science Conference Proceedings (OSTI)

The effects of dust on the radiative energy budget at the top of the atmosphere were investigated using model calculations and measurements from the Earth Radiation Budget Experiment (ERBE). Estimates of the dust optical depth were made from ...

Steven A. Ackerman; Hyosang Chung

1992-02-01T23:59:59.000Z

138

The Effect of Tropospheric Aerosols on the Earth's Radiation Budget: A Parameterization for Climate Models  

Science Conference Proceedings (OSTI)

Guided by the results of doubling-adding solutions to the equation of radiative transfer, we develop a simple technique for incorporating in climate models the effect of the background tropospheric aerosol on solar radiation. Because the ...

James A. Coakley Jr.; Robert D. Cess; Franz B. Yurevich

1983-01-01T23:59:59.000Z

139

A Climatology of Surface Cloud Radiative Effects at the ARM Tropical Western Pacific Sites  

Science Conference Proceedings (OSTI)

Cloud radiative effects on surface downwelling fluxes are investigated using datasets from the Atmospheric Radiation Measurement Program (ARM) sites in the tropical western Pacific Ocean (TWP) region. The Nauru Island (Republic of Nauru) and ...

Sally A. McFarlane; Charles N. Long; Julia Flaherty

2013-04-01T23:59:59.000Z

140

Influence of Ice Particle Surface Roughening on the Global Cloud Radiative Effect  

Science Conference Proceedings (OSTI)

Ice clouds influence the climate system by changing the radiation budget and large-scale circulation. Therefore, climate models need to have an accurate representation of ice clouds and their radiative effects. In this paper, new broadband ...

Bingqi Yi; Ping Yang; Bryan A. Baum; Tristan L'Ecuyer; Lazaros Oreopoulos; Eli J. Mlawer; Andrew J. Heymsfield; Kuo-Nan Liou

2013-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Radiation Effects on Transport and Bubble Formation in Silicate Glasses  

DOE Green Energy (OSTI)

Using advanced magnetic resonance spectroscopies and small-cluster modeling, atomic structure of radiation-induced point defects in alkali borate, silicate, and borosilicate glasses is fully characterized. It is shown that in boron-containing glasses, most of these point defects are electrons/holes trapped by cation/anion vacancies, such as O1 - - O3 + valence-alternation pairs. In microscopically phase-separated borosilicate glasses, radiation-induced defects are found to cluster at the interface between the borate and silicate phases. Reaction and diffusion dynamics of defect-annealing interstitial hydrogen atoms in boron and silica oxide glasses are studied. The yield of radiolytic O2 is estimated. This oxygen is shown to be the final product of triplet exciton decay. Plausible mechanisms for the oxygen bubble formation are put forward. Two practical conclusions relevant for the EMSP mission are made: First, the yield of radiolytic oxygen is shown to be too low to interfere with the storage of vitrified radioactive waste in the first 10 Kyr. Second, microscopic phase separation is demonstrated to increase both the chemical and radiation stability of borosilicate glass.

Trifunac, A.D.; Shkrob, I.A.; Werst, D.W.

2001-12-31T23:59:59.000Z

142

Multi-Dimensional Effects in Longwave Radiative Forcing of PBL Clouds  

NLE Websites -- All DOE Office Websites (Extended Search)

Multi-Dimensional Effects in Longwave Radiative Forcing of PBL Clouds D. B. Mechem and Y. L. Kogan Cooperative Institute for Mesoscale Meteorological Studies University of Oklahoma Norman, Oklahoma M. Ovtchinnikov Pacific Northwest National Laboratory Richland, Washington K. F. Evans University of Colorado Boulder, Colorado A. B. Davis Los Alamos National Laboratory Los Alamos, New Mexico R. F. Cahalan National Aeronautic and Space Administration Goddard Space Flight Center Greenbelt, Maryland E. E. Takara and R. G. Ellingson Florida State University Tallahassee, Florida 1. Introduction Numerical cloud models nearly universally employ one-dimensional (1D) treatments of radiative transfer (RT). Radiative transfer is typically implemented as a 2- or 4-stream approximation to the

143

Radiators  

SciTech Connect

A heat-exchange radiator is connected to a fluid flow circuit by a connector which provides one member of an interengageable spigot and socket pair for push-fit, fluid-tight, engagement between the connector and the radiator, with latching formations at least one of which is resilient. Preferably the connector carries the spigot which tapers and engages with a socket of corresponding shape, the spigot carrying an O-ring seal and either latching fingers or a resilient latching circlip.

Webster, D. M.

1985-07-30T23:59:59.000Z

144

A study of longwave radiation codes for climate studies: Validation with ARM observations and tests in general circulation models. Technical report, 16 March 1991--15 March 1992  

SciTech Connect

Research by the US Department of Energy (DOE) has shown that cloud radiative feedback is the single most important effect determining the magnitude of possible climatic responses to human activity. However, these effects are still not known at the levels needed for climate prediction. Consequently, DOE has launched a major initiative-- the Atmospheric Radiation Measurements (ARM) Program -- directed at improving the parameterization of the physics governing cloud and radiative processes in general circulation models (GCM`s). One specific goal of ARM is to improve the treatment of radiative transfer in GCM`s under clear-sky, general overcast and broken cloud conditions. Our approach to developing the radiation model will be to test existing models in an iterative, predictive fashion. We will supply the Clouds and Radiative Testbed (CART) with a set of models to be compared with operationally observed data. The differences we find will lead to the development of new models to be tested with new data. Similarly, our GCM studies will use existing GCM`s to study the radiation sensitivity problem. We anticipate that the outcome of this approach will provide both a better longwave radiative forcing algorithm and a better understanding of how longwave radiative forcing influences the equilibrium climate of the atmosphere.

Ellingson, R.G.; Baer, F.

1992-06-01T23:59:59.000Z

145

Posters Treatment of Cloud Radiative Effects in General Circulation...  

NLE Websites -- All DOE Office Websites (Extended Search)

study the effects of cloudradiation- climate interaction on climate simulations. This report summarizes project progress from March 1993 to March 1994. During this period, four...

146

Silicon field-effect transistors as radiation detectors for the Sub-THz range  

SciTech Connect

The nonresonance response of silicon metal-oxide-semiconductor field-effect transistors (Si-MOSFETs) with a long channel (1-20 {mu}m) to radiation in the frequency range 43-135 GHz is studied. The transistors are fabricated by the standard CMOS technology with 1-{mu}m design rules. The volt-watt sensitivity and the noise equivalent power (NEP) for such detectors are estimated with the calculated effective area of the detecting element taken into account. It is shown that such transistors can operate at room temperature as broadband direct detectors of sub-THz radiation. In the 4-5 mm range of wavelengths, the volt-watt sensitivity can be as high as tens of kV/W and the NEP can amount to 10{sup -11} - 10{sup -12}W/{radical}Hz . The parameters of detectors under study can be improved by the optimization of planar antennas.

But, D. B., E-mail: but.dmitry@gmail.com; Golenkov, O. G.; Sakhno, N. V.; Sizov, F. F.; Korinets, S. V.; Gumenjuk-Sichevska, J. V.; Reva, V. P.; Bunchuk, S. G. [National Academy of Sciences of Ukraine, Lashkaryov Institute of Semiconductor Physics (Ukraine)

2012-05-15T23:59:59.000Z

147

Low Dose Radiation Research Program: Real-Time Molecular Study...  

NLE Websites -- All DOE Office Websites (Extended Search)

Real-Time Molecular Study of Bystander Effects Using Imaging and Nano-Particle Optics Mohan Natarajan University of Texas Health Science Center Why this Project? To develop...

148

New study sees greater low-level radiation threat  

SciTech Connect

A new analysis of Energy Department medical records has found higher than expected cancer rates among workers at DOE's Hanford nuclear weapons plant, suggesting occupational exposure to low-level radiation may be more dangerous than previously thought. The study, released Tuesday by the Philadelphia-based Three Mile Island Public Health Fund, is important not only because of its controversial conclusions, but also because it represents the first independent review of DOE's long-secret worker medical records. The new study done by Stewart and Kneale looked at Hanford worker health records dating up to 1986 - part of a huge trove of data withheld by DOE from independent researchers until two years ago. In their re-analysis of the Hanford worker records, Stewart and Kneale found increased cancer rates among older workers who were over 40 years of age when exposed. And they said that increased susceptibility of older people to radiation-induced cancer was not reflected in the highly influential Japanese atomic bomb studies because people over 50 years of age were [open quotes]grossly under-represented[close quotes] in the A-bomb analyses, possibly because many bomb victims suffered early deaths from high doses.

Lobsenz, G.

1992-12-09T23:59:59.000Z

149

Oxide Multilayer Thermal Radiation Energy Reflection EBCs: Effect ...  

Science Conference Proceedings (OSTI)

Environmental barrier coatings (EBCs) with thermal radiation energy reflection have been developed recently. The EBCs utilize interaction between ...

150

Effects of stratospheric perturbations on the solar radiation budget  

DOE Green Energy (OSTI)

The changes in solar absorption and in local heating rates due to perturbations to O/sub 3/ and NO/sub 2/ concentrations caused by stratospheric injection of NO/sub x/ and CFM pollutants are assessed. The changes in species concentration profiles are derived from theoretical calculations using a transport-kinetics model. Because of significant changes in our understanding of stratospheric chemistry during the past year, the assessment of the effect of stratospheric perturbations on the solar radiation budget differs from previous assessments. Previously, a reduction in O/sub 3/ due to an NO/sub x/ injection caused a net decrease in the gaseous solar absorption;now the same perturbation leads to a net increase. The implication of these changes on the surface temperature is also discussed.

Luther, F.M.

1978-04-01T23:59:59.000Z

151

DUCRETE Shielding: A Cost Effective Alternative Radiation Shield  

NLE Websites -- All DOE Office Websites (Extended Search)

Summary Submitted to Spectrum 2000, Sept 24-28, 2000, Chattanooga, TN Summary Submitted to Spectrum 2000, Sept 24-28, 2000, Chattanooga, TN DUCRETE: A Cost Effective Radiation Shielding Material W. J. Quapp, Starmet CMI W. H. Miller, University of Missouri-Columbia James Taylor, Starmet CMI Colin Hundley, Starmet CMI Nancy Levoy, Starmet Corporation 1. INTRODUCTION A consequence of uranium enrichment in the US has been the accumulation of nearly 740,000 metric tons of depleted uranium hexafluoride (UF 6 ) tails. 1 While this material was once considered a feed stock for the United States Breeder Reactor Program, it is no longer needed. Alternative uses of depleted uranium are few. Some have been used for medical isotope transport casks, some for industrial radioactive source shields, some for military anti-tank

152

POLARIZATION STUDIES OF CdZnTe DETECTORS USING SYNCHROTRON X-RAY RADIATION.  

Science Conference Proceedings (OSTI)

New results on the effects of small-scale defects on the charge-carrier transport in single-crystal CdZnTe (CZT) material were produced. We conducted detailed studies of the role of Te inclusions in CZT by employing a highly collimated synchrotron x-ray radiation source available at Brookhaven's National Synchrotron Light Source (NSLS). We were able to induce polarization effects by irradiating specific areas with the detector. These measurements allowed the first quantitative comparison between areas that are free of Te inclusions and those with a relatively high concentration of inclusions. The results of these polaration studies will be reported.

CAMARDA,G.S.; BOLOTNIKOV, A.E.; CUI, Y.; HOSSAIN, A.; JAMES, R.B.

2007-07-01T23:59:59.000Z

153

EPIDEMIOLOGICAL STUDIES ON RADIATION CARCINOGENESIS IN HUMAN POPULATIONS FOLLOWING ACUTE EXPOSURE: NUCLEAR EXPLOSIONS AND MEDICAL RADIATION  

E-Print Network (OSTI)

exposure to radioactive fallout in Radiation-Associated inIslanders, who were exposed to fallout H-bomb test explosion

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

154

The NOAA Integrated Surface Irradiance Study (ISIS)—A New Surface Radiation Monitoring Program  

Science Conference Proceedings (OSTI)

This paper describes a new radiation monitoring program, the Integrated Surface Irradiance Study (ISIS), that builds upon and takes over from earlier NOAA networks monitoring components of solar radiation [both the visible component (SOLRAD) and ...

B. B. Hicks; J. J. DeLuisi; D. R. Matt

1996-12-01T23:59:59.000Z

155

Investigation of non-targeted effects of low dose ionizing radiation...  

NLE Websites -- All DOE Office Websites (Extended Search)

Investigation of non-targeted effects of low dose ionizing radiation on the mammary gland utilizing three-dimensional culture models of mammary cells derived from mouse strains...

156

Investigating the Effects of Radiation on Phosphonium-Based Ionic Liquids.  

E-Print Network (OSTI)

??This thesis presents work on the understanding of the effects of ionizing radiation on phosphonium-based ionic liquids (ILs). The capability of ILs to dissolve a… (more)

Howett, Susan

2013-01-01T23:59:59.000Z

157

A review of ground-based heavy-ion radiobiology relevant to space radiation risk assessment: Part II. Cardiovascular and immunological effects  

Science Conference Proceedings (OSTI)

The future of manned space flight depends on an analysis of the numerous potential risks of travel into deep space. Currently no radiation dose limits have been established for these exploratory missions. To set these standards more information is needed about potential acute and late effects on human physiology from appropriate radiation exposure scenarios, including pertinent radiation types and dose rates. Cancer risks have long been considered the most serious late effect from chronic daily relatively low-dose exposures to the complex space radiation environment. However, other late effects from space radiation exposure scenarios are under study in ground-based accelerator facilities and have revealed some unique particle radiation effects not observed with conventional radiations. A comprehensive review of pertinent literature that considers tissue effects of radiation leading to functional detriments in specific organ systems has recently been published (NCRP National Council on Radiation Protection and Measurements, Information Needed to Make Radiation Protection Recommendations for Space Missions Beyond Low-Earth Orbit, Report 153, Bethesda, MD, 2006). This paper highlights the review of two non-cancer concerns from this report: cardiovascular and immunological effects.

Blakely, Eleanor A.; Chang, Polly Y.

2007-02-26T23:59:59.000Z

158

Atomistic Methods for the Investigation of Radiation Effects  

Science Conference Proceedings (OSTI)

The results will illustrate those aspects of radiation damage production that are unique to iron as well as those that are more generic. A comparison between the  ...

159

The Effect of Directional Radiation Models on the Interpretation of Earth Radiation Budget Measurements  

Science Conference Proceedings (OSTI)

A parameter estimation technique is presented to estimate the radiative flux density distribution over the earn from a set of radiometer measurements at satellite altitude. The technique analyzes measurements from a wide field of view, horizon to ...

Richard N. Green

1980-10-01T23:59:59.000Z

160

Carbonaceous Aerosols and Radiative...  

NLE Websites -- All DOE Office Websites (Extended Search)

Aerosols and Radiative Effects Study Science Objective This field campaign is designed to increase scientific knowledge about the evolution of black carbon, primary organic...

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Radiation evaluation study of LSI RAM technologies. Final report  

SciTech Connect

Five commercial LSI static RAM technologies having a 1 kilobit capacity were radiation characterized. Arrays from the TTL, Schottky TTL, NMOS, CMOS, and CMOS/SOS families were evaluated. Radiation failure thresholds for gamma dose-rate logic upset, total gamma dose survivability, and neutron fluence survivability were determined. Included is a brief analysis of the radiation failure mechanism for each of the logic families tested.

Dinger, G.L.; Knoll, M.G.

1980-01-01T23:59:59.000Z

162

ORISE: Worker Health Studies - Radiation Exposure Data Collection  

NLE Websites -- All DOE Office Websites (Extended Search)

Overview Argonne Electronic Medical Records System Beryllium Testing and Surveillance Radiation Exposure Information and Reporting System (REIRS) U.S. Department of Energy...

163

EPIDEMIOLOGICAL STUDIES ON RADIATION CARCINOGENESIS IN HUMAN POPULATIONS FOLLOWING ACUTE EXPOSURE: NUCLEAR EXPLOSIONS AND MEDICAL RADIATION  

E-Print Network (OSTI)

Atomic Bomb by Radiation Dose, Years Research Research after Survivors, Hiroshima and Nagasaki, 1950-71 Exposure, Age,atomic bomb survivors in Hiroshima and Nagasaki (36), and the Japanese Here, 'here is an The latent age-

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

164

Cobalt-60 simulation of LOCA (loss of coolant accident) radiation effects  

Science Conference Proceedings (OSTI)

The consequences of simulating nuclear reactor loss of coolant accident (LOCA) radiation effects with Cobalt-60 gamma ray irradiators have been investigated. Based on radiation induced damage in polymer base materials, it was demonstrated that electron/photon induced radiation damage could be related on the basis of average absorbed radiation dose. This result was used to estimate the relative effectiveness of the mixed beta/gamma LOCA and Cobalt-60 radiation environments to damage both bare and jacketed polymer base electrical insulation materials. From the results obtained, it is concluded that present simulation techniques are a conservative method for simulating LOCA radiation effects and that the practices have probably substantially overstressed both bare and jacketed materials during qualification testing. 9 refs., 8 figs., 5 tabs.

Buckalew, W.H.

1989-07-01T23:59:59.000Z

165

[Treatment of cloud radiative effects in general circulation models  

SciTech Connect

This is a renewal proposal for an on-going project of the Department of Energy (DOE)/Atmospheric Radiation Measurement (ARM) Program. The objective of the ARM Program is to improve the treatment of radiation-cloud in GCMs so that reliable predictions of the timing and magnitude of greenhouse gas-induced global warming and regional responses can be made. The ARM Program supports two research areas: (I) The modeling and analysis of data related to the parameterization of clouds and radiation in general circulation models (GCMs); and (II) the development of advanced instrumentation for both mapping the three-dimensional structure of the atmosphere and high accuracy/precision radiometric observations. The present project conducts research in area (I) and focuses on GCM treatment of cloud life cycle, optical properties, and vertical overlapping. The project has two tasks: (1) Development and Refinement of GCM Radiation-Cloud Treatment Using ARM Data; and (2) Validation of GCM Radiation-Cloud Treatment.

Wang, W.C.

1993-11-01T23:59:59.000Z

166

Symposium-in-Print Interactive Effects of Ultraviolet-B Radiation and Temperature on Cotton Physiology, Growth  

E-Print Network (OSTI)

Current conditions of 2–11 kJ m 22 day 21 of UV-B radiation and temperatures of>308C during flowering in cotton cultivated regions are projected to increase in the future. A controlled environment study was conducted in sunlit growth chambers to determine the effects of UV-B radiation and temperature on physiology, growth, development and leaf hyperspectral reflectance of cotton. Plants were grown in the growth chambers at three day/night temperatures (24/168C, 30/228C and 36/288C) and three levels of UV-B radiation (0, 7 and 14 kJ m 22 day 21) at each temperature from emergence to 79 days under optimum nutrient and water conditions. Increases in main stem node number and the node of first fruiting branch and decrease in duration to first flower bud (square) and flower were recorded with increase in temperature. Main effects of temperature and UV-B radiation were significant for net photosynthetic rates, stomatal conductance, total chlorophyll and carotenoid concentrations of uppermost, fully expanded leaves during squaring and flowering. A significant interaction between temperature and UV-B radiation was detected for total biomass and its components. The UV-B radiation of 7 kJ m 22 day 21 reduced boll yield by 68% and 97 % at 30/228C and 36/288C, respectively, compared with yield at 0 kJ m 22 day 21 and 30/228C. No bolls were produced in the three temperature treatments under 14 kJ m 22 day 21 UV-B radiation. The first-order interactions between temperature, UV-B radiation and leaf age were significant for leaf reflectance. This study suggests a growth- and process-related temperature dependence of sensitivity to UV-B radiation.

Hyperspectral Reflectance; K. Raja Reddy; Vijaya Gopal Kakani; Duli Zhao; Sailaja Koti; Wei Gao

2003-01-01T23:59:59.000Z

167

Low Dose Radiation Research Program: Real-time Study of Signal Transduction  

NLE Websites -- All DOE Office Websites (Extended Search)

Real-time Study of Signal Transduction Pathways Involving in Real-time Study of Signal Transduction Pathways Involving in Bystander Effects Using Single Nanoparticle Optics and Single Living Cell Imaging Authors: Prakash D. Nallathamby, X. Nancy Xu, Mohan Natarajan Institutions: Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, Virginia and Department of Radiation Oncology, The University of Texas Health Science Center, San Antonio, Texas The mechanisms of bystander effects remain largely unknown. Bystander responses are thought to depend on activation of cellular communication processes. Recent studies have speculated that several crucial signal transduction pathways could play a major role in bystander effects. These crucial signal transduction pathways are controlled by a coordinated

168

Activities of the National Academy of Sciences in relation to the Radiation Effects Research Foundation  

SciTech Connect

This progress report relates progress in the various research projects evaluating the late health effects, both somatic and genetic, resulting from radiation exposure of the survivors of the atomic bombs at Hiroshima and Nagasaki, Japan. Considerable progress has been made in the collection and utilization of the various epidemiological data bases. These include the Life Span Study, (LSS) cohort, the Adult Health Study (AHS) cohort, the In Utero cohort, the leukemia registry and the F-1 Study population. Important progress has been made in using RERF Tumor and Tissue Registry records for evaluation of cancer incidence and radiation risk estimates for comparison with cancer mortality and risk in the LSS cohort. At the present time, a manuscript on the incidence of solid tumors (1950-1987) is undergoing internal and external review for publication as an RERF Technical report (TR) and for publication in a peer-reviewed scientific journal. In addition, manuscripts are in preparation on (1) a comprehensive report on the incidence of hematological cancers, including analysis of leukemia by cell type (1950-1987), (2) a general description of Tumor Registry operations and (3) a comparison of incidence- and mortality-based estimates of radiation risk in the LSS cohort.

Edington, C.W.

1992-06-01T23:59:59.000Z

169

Stochastic modeling of the cell killing effect for low- and high-LET radiation  

E-Print Network (OSTI)

Theoretical modeling of biological response to radiation describes qualitatively and quantitatively the results of radiobiological effects at the molecular, chromosomal, and cellular level. The repair-misrepair (RMR) model is the radiobiological model chosen for our study. It models deoxyribonucleic acid (DNA) damage formation and lesion repair through linear and quadratic processes. Double strand breaks (DSB) are a critical lesion in DNA. With increasing LET, the number of DSB per track traversing the cell nucleus increases. Using a compound Poisson process (CPP), we describe DNA damage formation. Three models were considered: a simple CPP using constant LET, a CPP using a chord length distribution, and a CPP using specific energy distribution. In the two first cases, and for low LET radiation the initial distribution of DSB was well approximated by a Poisson distribution, while for high LET radiation the initial distribution of DSB deviated slightly from a Poisson distribution. In the last case, DSB distribution was much broader than a pure Poisson distribution. Datasets from the literature for seven human cell lines, exhibiting various sensitivities to radiation were analyzed. We compared stochastic, CPP, and CPP using chord length distribution, with deterministic RMR models. For low LET radiation and at high dose rates the stochastic survival results agree well with the deterministic survival results. Also the stochastic model allows for non-linearity at low doses due to the accumulation of sub-lethal damage. At low dose rates deterministic results overestimate the surviving fraction compared to stochastic results. For high LET radiation stochastic and deterministic survival results agree. Stochastic survival results using specific energy distribution diverged from deterministic results by underestimating the surviving fraction at low and high LET radiation. The dose rate sparing curve, representing surviving fraction at a dose of 10Gy vs. dose rate shows that deterministic survival results are consistent with stochastic survival results, using CPP, or CPP with chord length distribution, for low and high dose rate values. Compared to deterministic aspects of DNA damage formation we concluded that stochastic aspects of DNA damage formation and repair using CPP or CPP with chord length distribution are not as prominent as reported in the earlier studies.

Partouche, Julien

2004-12-01T23:59:59.000Z

170

THE EFFECT OF RADIATION ON THE CORROSION OF METALS BY WATER. (Problem No. 322 MLC 2213)  

SciTech Connect

Long-time tests have been made on the effect of various types of radiation on the corrosion of 2S aluminum in simulated W water. In no case was any acceleration of corrosion by the radiation observed; the effect of radiation, if any, appeared to be a protective one. Deuteron irradiation did accelerate the corrosion of mild steel at low flow rates in hot water of pH 6 to 7, but no appreciable effect was observed with copper, stainless steel, or tuballoy. The general theory of the effect of radiation on corrosion is discussed, with the conclusion that no acceleration of corrosion by radiation is to be expected in most cases of practical interest. (auth)

Allen, A.O.; Bowman, M.C.; Goldowski, N.; Larson, R.G.; Treiman, L.

1944-07-06T23:59:59.000Z

171

Radiative Cooling Effects within and above the Nocturnal Boundary Layer  

Science Conference Proceedings (OSTI)

For representative tropospheric profiles of water vapor, CO2 and temperature we have calculated in situ longwave radiative flux divergence for use in a simplified second-order closure model of nocturnal boundary-layer evolution. The time ...

J. R. Garratt; R. A. Brost

1981-12-01T23:59:59.000Z

172

Radiation Effects in Ceramic Oxide and Novel LWR Fuels  

Science Conference Proceedings (OSTI)

Jul 31, 2011 ... TMS/ASM: Nuclear Materials Committee ... of radiation response of nuclear fuel through experiment, theory and computational multi-scale modeling. ... test reactors and commercial nuclear power reactors are all of interest.

173

Predicting Nonauditory Adverse Radiation Effects Following Radiosurgery for Vestibular Schwannoma: A Volume and Dosimetric Analysis  

SciTech Connect

Purpose: To define clinical and dosimetric predictors of nonauditory adverse radiation effects after radiosurgery for vestibular schwannoma treated with a 12 Gy prescription dose. Methods: We retrospectively reviewed our experience of vestibular schwannoma patients treated between September 2005 and December 2009. Two hundred patients were treated at a 12 Gy prescription dose; 80 had complete clinical and radiological follow-up for at least 24 months (median, 28.5 months). All treatment plans were reviewed for target volume and dosimetry characteristics; gradient index; homogeneity index, defined as the maximum dose in the treatment volume divided by the prescription dose; conformity index; brainstem; and trigeminal nerve dose. All adverse radiation effects (ARE) were recorded. Because the intent of our study was to focus on the nonauditory adverse effects, hearing outcome was not evaluated in this study. Results: Twenty-seven (33.8%) patients developed ARE, 5 (6%) developed hydrocephalus, 10 (12.5%) reported new ataxia, 17 (21%) developed trigeminal dysfunction, 3 (3.75%) had facial weakness, and 1 patient developed hemifacial spasm. The development of edema within the pons was significantly associated with ARE (p = 0.001). On multivariate analysis, only target volume is a significant predictor of ARE (p = 0.001). There is a target volume threshold of 5 cm3, above which ARE are more likely. The treatment plan dosimetric characteristics are not associated with ARE, although the maximum dose to the 5th nerve is a significant predictor of trigeminal dysfunction, with a threshold of 9 Gy. The overall 2-year tumor control rate was 96%. Conclusions: Target volume is the most important predictor of adverse radiation effects, and we identified the significant treatment volume threshold to be 5 cm3. We also established through our series that the maximum tolerable dose to the 5th nerve is 9 Gy.

Hayhurst, Caroline; Monsalves, Eric; Bernstein, Mark; Gentili, Fred [Gamma Knife Unit, Division of Neurosurgery, University Health Network, Toronto (Canada); Heydarian, Mostafa; Tsao, May [Radiation Medicine Program, Princess Margaret Hospital, Toronto (Canada); Schwartz, Michael [Radiation Oncology Program and Division of Neurosurgery, Sunnybrook Hospital, Toronto (Canada); Prooijen, Monique van [Radiation Medicine Program, Princess Margaret Hospital, Toronto (Canada); Millar, Barbara-Ann; Menard, Cynthia [Radiation Oncology Program, Princess Margaret Hospital, Toronto (Canada); Kulkarni, Abhaya V. [Division of Neurosurgery, Hospital for Sick Children, University of Toronto (Canada); Laperriere, Norm [Radiation Oncology Program, Princess Margaret Hospital, Toronto (Canada); Zadeh, Gelareh, E-mail: Gelareh.Zadeh@uhn.on.ca [Gamma Knife Unit, Division of Neurosurgery, University Health Network, Toronto (Canada)

2012-04-01T23:59:59.000Z

174

A Systematic Study of Longwave Radiative Heating and Cooling within Valleys and Basins Using a Three-Dimensional Radiative Transfer Model  

Science Conference Proceedings (OSTI)

The Monte Carlo code for the physically correct tracing of photons in cloudy atmospheres (MYSTIC) three-dimensional radiative transfer model was used in a parametric study to determine the strength of longwave radiative heating and cooling in ...

Sebastian W. Hoch; C. David Whiteman; Bernhard Mayer

2011-12-01T23:59:59.000Z

175

Research Programs on Low-Level Radiation Health Effects Supported by FEPCO  

SciTech Connect

The federation of Electric Power Companies (FEPCO) of Japan has been supporting several research projects on low-level radiation health effects for the purpose of the following: 1. to assist in the establishment of a reasonable system of radiation protection; 2. to release the public from unnecessary fear of ionizing radiation. We present some of the findings and current research programs funded or supported by FEPCO.

Kaneko, Masahito

1999-06-06T23:59:59.000Z

176

Radiation Energy Budget Studies Using Collocated AVHRR and ERBE Observations  

Science Conference Proceedings (OSTI)

Changes in the energy balance at the top of the atmosphere are specified as a function of atmospheric and surface properties using observations from the Advanced Very High Resolution Radiometer (AVURR) and the Earth Radiation budget Experiment (...

Steven A. Ackerman; Toshiro Inoue

1994-03-01T23:59:59.000Z

177

Study of a nonhomogeneous aerogel radiator in a proximity focusing  

E-Print Network (OSTI)

The use of a nonhomogeneous aerogel radiator, i.e. one consisting of layers with different refractive indices, has been shown to improve the resolution of the Cherenkov angle measured with a proximity focusing RICH detector. In order to obtain further information on the performance of such a detector, a simple model has been used to calculate the resolution and search for optimal radiator parameters. 1.

Rich Detector; Peter Kri?zan Ab; Samo Korpar Cb; Toru Iijima D

2006-01-01T23:59:59.000Z

178

Study of Aerosol Indirect Effects in China  

NLE Websites -- All DOE Office Websites (Extended Search)

Aerosol Indirect Effects in China In 2008, the U.S. Department of Energy (DOE)'s Atmospheric Radiation Measurement (ARM) Climate Research Facility is providing the ARM Mobile...

179

Accuracy of Humidity Measurement on Ships: Consideration of Solar Radiation Effects  

Science Conference Proceedings (OSTI)

The effect of heating due to solar radiation on measurements of humidity obtained from ships is examined. Variations in wet- and dry-bulb temperature measured on each side of a research ship are shown to correlate with solar radiation. However, ...

Elizabeth C. Kent; Peter K. Taylor

1996-12-01T23:59:59.000Z

180

Topographic Effects on the Surface Radiation Balance in and around Arizona’s Meteor Crater  

Science Conference Proceedings (OSTI)

The individual components of the slope-parallel surface radiation balance were measured in and around Arizona’s Meteor Crater to investigate the effects of topography on the radiation balance. The crater basin has a diameter of 1.2 km and a depth ...

Sebastian W. Hoch; C. David Whiteman

2010-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Longwave Band-By-Band Cloud Radiative Effect and Its Application in GCM Evaluation  

Science Conference Proceedings (OSTI)

The cloud radiative effect (CRE) of each longwave (LW) absorption band of a GCM’s radiation code is uniquely valuable for GCM evaluation because 1) comparing band-by-band CRE avoids the compensating biases in the broadband CRE comparison and 2) ...

Xianglei Huang; Jason N. S. Cole; Fei He; Gerald L. Potter; Lazaros Oreopoulos; Dongmin Lee; Max Suarez; Norman G. Loeb

2013-01-01T23:59:59.000Z

182

Effects of solar ultraviolet radiation on photosynthesis of higher plants  

SciTech Connect

Rates of net photosynthesis were measured until 13 different crop species grown under an enhanced UV light regime simulating that which would occur in the event of a 50% atmospheric ozone depletion. Results indicated that a 50% reduction in ozone would dramatically reduce yields of some major crop species. The effects of UV on photosynthesis were also studied; it was found that UV inhibited photosynthesis. 100 references, 6 figures, 15 tables.

Thai, V.K.

1975-01-01T23:59:59.000Z

183

Microsoft PowerPoint - htalk324_radiation_effects09aug051.ppt  

National Nuclear Security Administration (NNSA)

Electrical Effects of Ionizing Electrical Effects of Ionizing Radiation on Insulating Materials Harold P. Hjalmarson, Rudolph E. Magyar and Kenneth E. Kambour Sandia National Laboratories Albuquerque, NM 87185 AMS Conference August 24-28, 2009 Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000. 2 Radiation Effects: Evolution from Atomistic to Continuum Phenomena Time-Dependent Density Functional Theory (TDDFT): Rudy Magyar Two-Temperature Molecular Dynamics (MD): Paul Crozier Radiation Effects in Oxides and Semiconductors (REOS): HPH 3 Outline * Overview * Radiation Effects - Electronic cooling (TDDFT & REOS) - Atomic Rearrangement (MD & REOS)

184

Research Article Effect of Microwave Radiation on Enzymatic and Chemical Peptide Bond Synthesis on Solid Phase  

E-Print Network (OSTI)

Peptide bond synthesis was performed on PEGA beads under microwave radiations. Classical chemical coupling as well as thermolysin catalyzed synthesis was studied, and the effect of microwave radiations on reaction kinetics, beads ’ integrity, and enzyme activity was assessed. Results demonstrate that microwave radiations can be profitably exploited to improve reaction kinetics in solid phase peptide synthesis when both chemical and biocatalytic strategies are used. Copyright © 2009 Alessandra Basso et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The use of microwave (MW) heating has found successful applications in solid phase organic synthesis (SPOS) [1–7]. As far back as 1992, Wang described the use of a single-mode microwave as a heating source to accelerate the chemical coupling [8] of many amino acids. Reactions on SP often suffer from unsatisfactory reaction kinetics due to slow diffusion. Since microwave energy activates any molecule with dipole moment, a rapid heating at a molecular level is

Ra Basso; Loris Sinigoi; Lucia Gardossi; Sabine Flitsch

2009-01-01T23:59:59.000Z

185

Overview of fiber radiation effects testing at the Los Alamos National Laboratory  

SciTech Connect

Fiber optics offer potential benefits in diagnostic measurements associated with nuclear testing. Such applications require that optical fibers be located in close proximity to a nuclear test and provide a reliable data transmission path during exposure to intense radiation. The Los Alamos effort has thus concentrated on measurement and understanding of radiation effects in optical fibers at very short times (< 100 ns) after (and during) irradiation. This is in contrast to most other studies that concentrate on times of interest in military, nuclear power, or standard telecommunication applications (1 ms to years). The Los Alamos program has included laboratory tests with intense electron pulse facilities (Febetron 705 and 706) and a fast pulsed electron linac (located at EG and G, Inc. in Santa Barbara, California). In addition, several measurements have been conducted on nuclear tests and some of that data has been released in unclassified publications. This program has used fibers for many data transmission applications. Fibers have also been used as signal transducers by utilizing radiation-to-light conversion processes within the fiber. Past, present, and future activities in this program are discussed.

Lyons, P.B.

1983-01-01T23:59:59.000Z

186

Surface effects on the radiation response of nanoporous Au foams  

Science Conference Proceedings (OSTI)

We report on an experimental and simulation campaign aimed at exploring the radiation response of nanoporous Au (np-Au) foams. We find different defect accumulation behavior by varying radiation dose-rate in ion-irradiated np-Au foams. Stacking fault tetrahedra are formed when np-Au foams are irradiated at high dose-rate, but they do not seem to be formed in np-Au at low dose-rate irradiation. A model is proposed to explain the dose-rate dependent defect accumulation based on these results.

Fu, E. G.; Caro, M.; Wang, Y. Q.; Baldwin, K.; Caro, A. [Materials Science in Radiation and Dynamics Extremes, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Zepeda-Ruiz, L. A. [Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Bringa, E. [CONICET and Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza 5500 (Argentina); Nastasi, M. [Nebraska Center for Energy Sciences Research, University of Nebraska-Lincoln, Lincoln, Nebraska 68508 (United States)

2012-11-05T23:59:59.000Z

187

Radiation Effects on Low-dimensional Carbon System  

E-Print Network (OSTI)

Ion irradiation has been known to be an effective tool for structure modification with micro/nano-scale precision. Recently, demonstrations have been made for nano-machining, such as the cutting and welding of carbon nanotubes. Understanding the fundamental effects of ion irradiation on carbon nanotubes is critical for advancing this technique as well as for scientific curiosity. Molecular dynamics modeling was performed to study irradiation stability, structural changes, and corresponding thermal properties. In our study, Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) was used to perform atomic scale simulation. In order to understand size and geometry effects on carbon damage creation, the threshold energy of displacement was calculated as a function of recoiling angles for both single-walled and multi-walled nanotubes. A strong directional dependence was found to exist in different shells of multi-walled carbon nanotubes. We found that carbon atoms on the innermost tube were more susceptible to be displaced toward the center of axis. The calculation matrix was further extended to nanotubes having different diameters for a full-scale understanding of the creation of defects. Besides studies on defects creation, thermal properties of carbon nanotubes were studied via a simplified model of the carbon nanotube network. Thermal conductivity, were found to be increased nearly one order of magnitude in carbon nanotube networks after irradiation and subsequent annealing. All the modeling results were compared with experimental observations either obtained from this project as a parallel study or from previous works, for the purpose of verification and validation. For experimental works, atomic scale characterization was performed by using transmission electron microscopy and the thermal conductivity measurement was characterized by using laser flash technique. Through a combination of modeling and experimentation, we proved that ion beam techniques can be used to enhance thermal conductivity in carbon nanotube bundles by inter-tube defects mediated phonon transport.

Wang, Jing

2013-08-01T23:59:59.000Z

188

Radiative Electron Capture Studied for Bare, Decelerated Uranium Th. Sthlker1,2  

E-Print Network (OSTI)

Radiative Electron Capture Studied for Bare, Decelerated Uranium Ions Th. StÃ?hlker1,2 , X. Ma1,3 ,T the deceleration technique for bare uranium ions at the ESR storage ring we studied the Radiative Electron Capture in collisions of bare uranium ions with light target atoms at low beam energies. This allows us to extend our

189

Workshop Report on Atomic Bomb Dosimetry--Residual Radiation Exposure: Recent Research and Suggestions for Future Studies  

SciTech Connect

There is a need for accurate dosimetry for studies of health effects in the Japanese atomic bomb survivors because of the important role that these studies play in worldwide radiation protection standards. International experts have developed dosimetry systems, such as the Dosimetry System 2002 (DS02), which assess the initial radiation exposure to gamma rays and neutrons but only briefly consider the possibility of some minimal contribution to the total body dose by residual radiation exposure. In recognition of the need for an up-to-date review of the topic of residual radiation exposure in Hiroshima and Nagasaki, recently reported studies were reviewed at a technical session at the 57th Annual Meeting of the Health Physics Society in Sacramento, California, 22-26 July 2012. A one-day workshop was also held to provide time for detailed discussion of these newer studies and to evaluate their potential use in clarifying the residual radiation exposures to the atomic-bomb survivors at Hiroshima and Nagasaki. Suggestions for possible future studies are also included in this workshop report.

none,

2013-06-06T23:59:59.000Z

190

BEIR-III report and the health effects of low-level radiation  

SciTech Connect

The present BEIR-III Committee has not highlighted any controversy over the health effects of low-level radiation. In its evaluation of the experimental data and epidemiological surveys, the Committee has carefully reviewed and assessed the value of all the available scientific evidence for estimating numerical risk coefficients for the health hazards to human populations exposed to low levels of ionizing radiation. Responsible public awareness of the possible health effects of ionizing radiations from medical and industrial radiation exposure, centers on three important matters of societal concern: (1) to place into perspective the extent of harm to the health of man and his descendants to be expected in the present and in the future from those societal activities involving ionizing radiation; (2) to develop quantitative indices of harm based on dose-effect relationships; such indices could then be used with prudent caution to introduce concepts of the regulation of population doses on the basis of somatic and genetic risks; and (3) to identify the magnitude and extent of radiation activities which could cause harm, to assess their relative significance, and to provide a framework for recommendations on how to reduce unnecessary radiation exposure to human populations. The main difference of the BEIR Committee Report is not so much from new data or new interpretations of existing data, but rather from a philosophical approach and appraisal of existing and future radiation protection resulting from an atmosphere of constantly changing societal conditions and public attitudes. (PCS)

Fabrikant, J.I.

1980-01-01T23:59:59.000Z

191

Effects of radiation and compression on propagating spherical flames of methane/air mixtures near the lean flammability limit  

SciTech Connect

Large discrepancies between the laminar flame speeds and Markstein lengths measured in experiments and those predicted by simulations for ultra-lean methane/air mixtures bring a great concern for kinetic mechanism validation. In order to quantitatively explain these discrepancies, a computational study is performed for propagating spherical flames of lean methane/air mixtures in different spherical chambers using different radiation models. The emphasis is focused on the effects of radiation and compression. It is found that the spherical flame propagation speed is greatly reduced by the coupling between thermal effect (change of flame temperature or unburned gas temperature) and flow effect (inward flow of burned gas) induced by radiation and/or compression. As a result, for methane/air mixtures near the lean flammability limit, the radiation and compression cause large amounts of under-prediction of the laminar flame speeds and Markstein lengths extracted from propagating spherical flames. Since radiation and compression both exist in the experiments on ultra-lean methane/air mixtures reported in the literature, the measured laminar flame speeds and Markstein lengths are much lower than results from simulation and thus cannot be used for kinetic mechanism validation. (author)

Chen, Zheng [State Key Laboratory for Turbulence and Complex Systems, Department of Mechanics and Aerospace Engineering, College of Engineering, Peking University, Beijing 100871 (China)

2010-12-15T23:59:59.000Z

192

EFFECTS OF triIODOTHYRONINE IN ALTERING THE RESPONSE OF KIDNEYS TO COBALT- 60 RADIATION  

SciTech Connect

The fear of inducing radiation nephritis restricts the amount of radiation delivered to retroperitonieal tumors. If this radiation injury could be modified, the therapist would then be less fearful of possibly inducing this often fatal complication. Since triiodothyronine has proved beneficial in reducing radiation injury of the skin and subcutaneous tissues, the effects of this compound were elvaluated following production of radiation injuiy in rabbit kidneys. Surprisingly, triiodothyronine did not favorably alter the reaction, but made it worse. The reason for this variance with the effects previously reported in skin is not certain. Tissue specificity or difference in vascularity may be important factors. The irradiated skin of the triiodothyroninetreated animals showed slightly less histologic alteration than the irradiated skin of the control animals. This tends to confirm the work of Glicksman and associates. (auth)

Caldwell, W.L.; Thomassen, R.W.; Bosch, A.

1963-10-01T23:59:59.000Z

193

Transport, Radiative, and Dynamical Effects of the Antarctic Ozone Hole: A GFDL “SKYHI” Model Experiment  

Science Conference Proceedings (OSTI)

The GFDL “SKYHI” general circulation model has been used to simulate the effect of the Antarctic “ozone hole” phenomenon on the radiative and dynamical environment of the lower stratosphere. Both the polar ozone destruction and photochemical ...

J. D. Mahlman; L. J. Umscheid; J. P. Pinto

1994-02-01T23:59:59.000Z

194

Propagation of CO2 Laser Radiation Through lce Clouds: Microphysical Effects  

Science Conference Proceedings (OSTI)

Preliminary investigation of the effects of irradiating artificial ice crystals with 10.6 ?m CO2, laser radiation reveals that laser beam-ice crystal interactions can be quite disruptive to ice cloud content under some conditions. The responsible ...

Kenneth Sassen; Mike Griffin

1981-07-01T23:59:59.000Z

195

Radiative Properties of Boundary Layer Clouds: Droplet Effective Radius versus Number Concentration  

Science Conference Proceedings (OSTI)

The plane-parallel model for the parameterization of clouds in global climate models is examined in order to estimate the effects of the vertical profile of the microphysical parameters on radiative transfer calculations for extended boundary ...

Jean-Louis Brenguier; Hanna Pawlowska; Lothar Schüller; Rene Preusker; Jürgen Fischer; Yves Fouquart

2000-03-01T23:59:59.000Z

196

Radiation and Strain Effects in Silicon-Germanium Bipolar Complementary Metal Oxide Semiconductor Technology .  

E-Print Network (OSTI)

??This work examines the effects of radiation and strain on silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) BiCMOS technology. First, aspects of the various SiGe HBT… (more)

Haugerud, Becca Mary

2005-01-01T23:59:59.000Z

197

Global, Seasonal Cloud Variations from Satellite Radiance Measurements. Part II. Cloud Properties and Radiative Effects  

Science Conference Proceedings (OSTI)

Global, daily, visible and infrared radiance measurements from the NOAA-5 Scanning Radiometer (SR) are analyzed for the months of January, April, July and October 1977 to infer cloud and surface radiative properties and their effects on the Earth ...

William B. Rossow; Andrew A. Lacis

1990-11-01T23:59:59.000Z

198

GCM Aerosol Radiative Effects Using Geographically Varying Aerosol Sizes Deduced from AERONET Measurements  

Science Conference Proceedings (OSTI)

Aerosol optical properties, and hence the direct radiative effects, are largely determined by the assumed aerosol size distribution. In order to relax the fixed aerosol size constraint commonly used in general circulation models (GCMs), ...

Glen Lesins; Ulrike Lohmann

2003-11-01T23:59:59.000Z

199

Study on development of education model and its evaluation system for radiation safety  

E-Print Network (OSTI)

As one of the detailed action strategy of multi object preparedness for strengthening of radiation safety management by MOST, this project was performed, in order to promote the safety culture for user and radiation worker through effective education program. For the prevention of radiological accident and effective implementation of radiation safety education and training, this project has been carried out the development of education model and its evaluation system on radiation safety. In the development of new education model, education course was classified; new and old radiation worker, temporary worker, lecturer and manager. The education model includes the contents of expanding the education opportunity and workplace training. In the development of evaluation system, the recognition criteria for commission-education institute and inside-education institute which should establish by law were suggested for evaluation program. The recognition criteria contains classification, student, method, facilities, ...

Seo, K W; Nam, Y M

2002-01-01T23:59:59.000Z

200

Adaptive Breast Radiation Therapy Using Modeling of Tissue Mechanics: A Breast Tissue Segmentation Study  

Science Conference Proceedings (OSTI)

Purpose: To validate and compare the accuracy of breast tissue segmentation methods applied to computed tomography (CT) scans used for radiation therapy planning and to study the effect of tissue distribution on the segmentation accuracy for the purpose of developing models for use in adaptive breast radiation therapy. Methods and Materials: Twenty-four patients receiving postlumpectomy radiation therapy for breast cancer underwent CT imaging in prone and supine positions. The whole-breast clinical target volume was outlined. Clinical target volumes were segmented into fibroglandular and fatty tissue using the following algorithms: physical density thresholding; interactive thresholding; fuzzy c-means with 3 classes (FCM3) and 4 classes (FCM4); and k-means. The segmentation algorithms were evaluated in 2 stages: first, an approach based on the assumption that the breast composition should be the same in both prone and supine position; and second, comparison of segmentation with tissue outlines from 3 experts using the Dice similarity coefficient (DSC). Breast datasets were grouped into nonsparse and sparse fibroglandular tissue distributions according to expert assessment and used to assess the accuracy of the segmentation methods and the agreement between experts. Results: Prone and supine breast composition analysis showed differences between the methods. Validation against expert outlines found significant differences (P<.001) between FCM3 and FCM4. Fuzzy c-means with 3 classes generated segmentation results (mean DSC = 0.70) closest to the experts' outlines. There was good agreement (mean DSC = 0.85) among experts for breast tissue outlining. Segmentation accuracy and expert agreement was significantly higher (P<.005) in the nonsparse group than in the sparse group. Conclusions: The FCM3 gave the most accurate segmentation of breast tissues on CT data and could therefore be used in adaptive radiation therapy-based on tissue modeling. Breast tissue segmentation methods should be used with caution in patients with sparse fibroglandular tissue distribution.

Juneja, Prabhjot, E-mail: Prabhjot.Juneja@icr.ac.uk [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom)] [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom); Harris, Emma J. [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom)] [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom); Kirby, Anna M. [Department of Academic Radiotherapy, Royal Marsden National Health Service Foundation Trust, Sutton (United Kingdom)] [Department of Academic Radiotherapy, Royal Marsden National Health Service Foundation Trust, Sutton (United Kingdom); Evans, Philip M. [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom)] [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom)

2012-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

A Systematic Study of GCM Sensitivity to Latitudinal Changes in Solar Radiation  

Science Conference Proceedings (OSTI)

Paleoclimatic data and climate model simulations have demonstrated that orbitally forced changes in solar radiation can have a pronounced effect on global climate. Key questions remain, however, about the spatial patterns in the climatic ...

Benjamin Felzer; Robert J. Oglesby; Hong Shao; Thompson Webb III; Dena E. Hyman; Warren L. Prell; John E. Kutzbach

1995-04-01T23:59:59.000Z

202

Low-Dose Radiation Cataract and Genetic Determinants of Radiosensitivi...  

NLE Websites -- All DOE Office Websites (Extended Search)

Our research utilizes radiation cataract as a model system to study the effects of low-dose ionizing radiation exposure in a complex, highly differentiated tissue. We believe...

203

Turbulence and Radiation in Stratocumulus Topped Marine Boundary Layers: A Case Study from VOCALS-REx  

Science Conference Proceedings (OSTI)

Observations made during a 24 hour period as part of the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) are analyzed to study the radiation and turbulence associated with stratocumulus topped marine boundary layer (BL). ...

Virendra P. Ghate; Bruce A. Albrecht; Mark A. Miller; Alan Brewer; Christopher W. Fairall

204

Health effects models for nuclear power plant accident consequence analysis: Low LET radiation  

SciTech Connect

This report describes dose-response models intended to be used in estimating the radiological health effects of nuclear power plant accidents. Models of early and continuing effects, cancers and thyroid nodules, and genetic effects are provided. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes -- are considered. In addition, models are included for assessing the risks of several nonlethal early and continuing effects -- including prodromal vomiting and diarrhea, hypothyroidism and radiation thyroiditis, skin burns, reproductive effects, and pregnancy losses. Linear and linear-quadratic models are recommended for estimating cancer risks. Parameters are given for analyzing the risks of seven types of cancer in adults -- leukemia, bone, lung, breast, gastrointestinal, thyroid, and other.'' The category, other'' cancers, is intended to reflect the combined risks of multiple myeloma, lymphoma, and cancers of the bladder, kidney, brain, ovary, uterus and cervix. Models of childhood cancers due to in utero exposure are also developed. For most cancers, both incidence and mortality are addressed. The models of cancer risk are derived largely from information summarized in BEIR III -- with some adjustment to reflect more recent studies. 64 refs., 18 figs., 46 tabs.

Evans, J.S. (Harvard Univ., Boston, MA (USA). School of Public Health)

1990-01-01T23:59:59.000Z

205

Human radiation studies: Remembering the early years: Oral history of radiation biologist Marvin Goldman, Ph.D., conducted December 22, 1994  

SciTech Connect

This report provides a transcript of an interview of Dr. Marvin Goldman by representatives of DOE`s Office of Human Radiation Experiments. Dr. Goldman was chosen for this interview because of his work on bone-seeking radionuclides. After a brief biographical sketch Dr. Goldman related his experiences concerning his training and work at Rochester University, his work at Brookhaven National Laboratory, his participation in the Beagle Studies at University of California at Davis, his work with the Chernobyl Nuclear Plant Accident, his consultation work with Russian authorities on the health and ecological effects in their history, and finally his opinions and recommendations on human radiation research and the environmental cleanup of DOE sites.

1995-09-01T23:59:59.000Z

206

Estimating Three-Dimensional Cloudy Radiative Transfer Effects from Time-Height Cross Sections  

NLE Websites -- All DOE Office Websites (Extended Search)

Estimating Three-Dimensional Cloudy Radiative Transfer Estimating Three-Dimensional Cloudy Radiative Transfer Effects from Time-Height Cross Sections C. Hannay and R. Pincus National Oceanic and Atmospheric Administration Climate Diagnostics Center Boulder, Colorado K. F. Evans Program in Atmospheric and Oceanic Sciences University of Colorado Boulder, Colorado Introduction Clouds in the atmosphere are finite in extent and variable in every direction and in time. Long data sets from ground-based profilers, such as lidars or cloud radars, could provide a very valuable set of observations to characterize this variability. We may ask how well such profiling instruments can represent the cloud structure as measured by the magnitude of the three-dimensional (3D) radiative transfer effect. The 3D radiative transfer effect is the difference between the domain average broadband solar surface

207

Cell type dependent radiation induced signaling and its effect on tissue regulation  

NLE Websites -- All DOE Office Websites (Extended Search)

Cell type dependent radiation induced signaling and its effect on tissue regulation Cell type dependent radiation induced signaling and its effect on tissue regulation Marianne B. Sowa, Claere von Neubeck, R. Joe Robinson, Paula M. Koehler, Norman J. Karin, Xihai Wang, Katrina M. Waters and Harish Shankaran Ionizing radiation exposure triggers a cell signaling program which includes proliferation, the DNA damage response, and tissue remodeling. The activated signaling pathways lead to the induction of both protective effects as well as adverse consequences. A fundamental question is whether signaling cascades initiated by low doses are fundamentally different than those initiated by high doses. To address this question we have applied a systems biology approach to examine the radiation induced temporal responses of an in vitro three dimensional (3D) human skin tissue model. Using microarray-

208

Summary of radiation damage studies on rare earth permanent magnets  

SciTech Connect

With the proposed use of permanent magnets for both the NLC and the VLHC the issue flux loss due to radiation damage needs to be fully understood. There exist many papers on the subject. There are many difficulties in drawing conclusions from all of these data. First there is the difference methods of dosimetry, second different types of magnets and magnetic arrangements, and third different manufacturers of magnet material. This paper provides a summary of the existing literature on the subject.

J. T. Volk

2002-11-19T23:59:59.000Z

209

Effect of internal alpha radiation on borosilicate glass containing Savannah River Plant waste  

DOE Green Energy (OSTI)

Effects of internal alpha radiation on borosilicate glass, a perspective matrix for long-term storage of Savannah River Plant (SRP) radioactive waste, were evaluated in samples containing 45 wt % simulated waste (Fe(OH)/sub 3/--MnO/sub 2/) and either 0.5 wt % /sup 244/Cm or 1 wt % /sup 238/Pu. A glass containing /sup 238/Pu without waste was also studied for comparison. The glasses were examined for changes in physical stability, leachability, and dilatation. Alpha dose rates in the test glasses ranged from 4.5 x 10/sup 14/ to 1.3 x 10/sup 15/ alpha dis/(g-day). After 420 days, microcracks had formed; however, no macrostructural damage to the glasses was observed. Leachabilities for /sup 244/Cm and /sup 238/Pu were <7 x 10/sup -8/ g/(cm/sup 2/-day) and were not affected by the radiation. Continuous leaching by water for 5 days removed <10/sup -5/% of the isotopes. Alpha radiolysis caused expansion of the simulated-waste glasses in proportion to dose. Application of these results to glass containing radioactive Savannah River Plant waste indicated that internal alpha radiolysis will not cause detrimental effects during long-term storage (>10/sup 6/ years) of the waste glass.

Bibler, N.E.; Kelley, J.A.

1978-05-01T23:59:59.000Z

210

Effects of Te inclusions on the performance of CdZnTe radiation detectors  

Science Conference Proceedings (OSTI)

Te inclusions existing at high concentrations in CdZnTe (CZT) material can degrade the performance of CZT detectors. These microscopic defects trap the free electrons generated by incident radiation, so entailing significant fluctuations in the total collected charge and thereby strongly affecting the energy resolution of thick (long-drift) detectors. Such effects were demonstrated in thin planar detectors, and, in many cases, they proved to be the dominant cause of the low performance of thick detectors, wherein the fluctuations in the charge losses accumulate along the charge's drift path. We continued studying this effect using different tools and techniques. We employed a dedicated beamline recently established at BNL's National Synchrotron Light Source for characterizing semiconductor radiation detectors, along with an IR transmission microscope system, the combination of which allowed us to correlate the concentration of defects with the devices performances. We present here our new results from testing over 50 CZT samples grown by different techniques. Our goals are to establish tolerable limits on the size and concentrations of these detrimental Te inclusions in CZT material, and to provide feedback to crystal growers to reduce their numbers in the material.

Bolotnikov,A.E.; Abdul-Jabber, N. M.; Babalola, O. S.; Camarda, G. S.; Cui, Y.; Hossain, A. M.; Jackson, E. M.; Jackson, H. C.; James, J. A.; Kohman, K. T.; Luryi, A. L.; James, R. B.

2008-10-19T23:59:59.000Z

211

Effect of Te Inclusions on the Performance of Cdznte Radiation Detectors  

Science Conference Proceedings (OSTI)

Te inclusions existing at high concentrations in CdZnTe (CZT) material can degrade the performance of CZT detectors. These microscopic defects trap the free electrons generated by incident radiation, so entailing significant fluctuations in the total collected charge and thereby strongly affecting the energy resolution of thick (long-drift) detectors. Such effects were demonstrated in thin planar detectors, and, in many cases, they proved to be the dominant cause of the low performance of thick detectors, wherein the fluctuations in the charge losses accumulate along the charge's drift path. We continued studying this effect using different tools and techniques. We employed a dedicated beamline recently established at BNL's National Synchrotron Light Source for characterizing semiconductor radiation detectors, along with an IR transmission microscope system, the combination of which allowed us to correlate the concentration of defects with the devices' performances. We present here our new results from testing over 50 CZT samples grown by different techniques. Our goals are to establish tolerable limits on the size and concentrations of these detrimental Te inclusions in CZT material, and to provide feedback to crystal growers to reduce their numbers in the material.

Bolotnikov, A.; Abdul-Jabbar, N; Babalola, O; Camarda, G; Cui, Y; Hossain, A; Jackson, E; Jackson, H; James, J; et. al.

2009-01-01T23:59:59.000Z

212

Radiation Protection Studies for LCLS Tune Up Dump  

Science Conference Proceedings (OSTI)

The Linac Coherent Light Source (LCLS) at the Stanford Linear Accelerator Center is a pioneer fourth generation hard x-ray free electron laser that shall start to deliver laser pulses in 2009. Among other components of LCLS that present radiation protection concerns, the tune up dump (tdund) is of special interest because it also constitutes an issue for machine protection, as it is placed close to radiation sensitive components, like electronic devices and permanent magnets in the undulators. This paper first introduces the stopper of tdund looking at the heat load, and then it describes the shielding around the dump necessary to maintain the prompt and residual dose within design values. Next, preliminary comparisons of the magnetization loss in a dedicated on-site magnet irradiation experiment with FLUKA simulations serve to characterize the magnetic response to radiation of magnets like those of LCLS. The previous knowledge, together with the limit for the allowed demagnetization, are used to estimate the lifetime of the undulator. Further simulations provide guidelines on which lifetime can be expected for an electronic device placed at a given distance of tdund.

Santana-Leitner, M.; Fass, A.; Mao, S.; Nuhn, H.D.; /SLAC; Roesler, S.; /CERN; Rokni, S.; Vollaire, J.; /SLAC

2010-04-29T23:59:59.000Z

213

Low Dose Radiation Program: Links - Agencies with Radiation Regulatory  

NLE Websites -- All DOE Office Websites (Extended Search)

Agencies with Radiation Regulatory Concerns and Involvement Agencies with Radiation Regulatory Concerns and Involvement Biological Effects of Low Level Exposures (BELLE) Canadian Nuclear Safety Commission Center for Risk Excellence Health Protection Agency The Health Risks of Extraterrestrial Environments International Commission on Radiation Units and Measurements, Inc. International Commission on Radiological Protection (ICRP) International Radiation Protection Association (IRPA) NASA Space Radiation Program National Academy of Sciences (NAS) Nuclear and Radiation Studies Board National Aeronautics and Space Administration (NASA) NASA OBRR Task Book Publication National Council on Radiation Protection (NCRP) National Institute of Environmental Health Sciences (NIEHS) National Toxicology Program (NTP) Occupational Safety and Health Administration (OSHA)

214

Radiation therapy of pediatric brain tumors : comparison of long-term health effects and costs between proton therapy and IMRT  

E-Print Network (OSTI)

Radiation therapy is an important component of pediatric brain tumor treatment. However, radiation-induced damage can lead to adverse long-term health effects. Proton therapy has the ability to reduce the dose delivered ...

Vu, An T. (An Thien)

2011-01-01T23:59:59.000Z

215

CRaTER: The Cosmic Ray Telescope for the Effects of Radiation Experiment on the Lunar Reconnaissance Orbiter Mission  

E-Print Network (OSTI)

The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on the Lunar Reconnaissance Orbiter (LRO) characterizes the radiation environment to be experienced by humans during future lunar missions. CRaTER measures the ...

Spence, H. E.

216

A Study of Cloud–Generated Radiative Heating and Its Generation of Available Potential Energy. Part I: Theoretical Background  

Science Conference Proceedings (OSTI)

The theory is presented of the effect of radiative heating and cooling by clouds on the available potential energy (APE). This provides a measure of the influence of clouds on the general circulation. Absorption and scattering of solar radiation ...

R. Stuhlmann; G. L. Smith

1988-12-01T23:59:59.000Z

217

Ultrafast time dynamics studies of periodic lattices with free electron laser radiation  

Science Conference Proceedings (OSTI)

It has been proposed that radiation from free electron laser (FEL) at Hamburg (FLASH) can be used for ultrafast time-resolved x-ray diffraction experiments based on the near-infrared (NIR) pump/FEL probe scheme. Here, investigation probing the ultrafast structural dynamics of periodic nano-crystalline organic matter (silver behenate) with such a scheme is reported. Excitation with a femtosecond NIR laser leads to an ultrafast lattice modification which time evolution has been studied through the scattering of vacuum ultraviolet FEL pulses. The found effect last for 6 ps and underpins the possibility for studying nanoperiodic dynamics down to the FEL source time resolution. Furthermore, the possibility of extending the use of silver behenate (AgBh) as a wavelength and temporal calibration tool for experiments with soft x-ray/FEL sources is suggested.

Quevedo, W.; Busse, G.; Hallmann, J.; More, R.; Petri, M.; Rajkovic, I. [Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Goettingen (Germany); Krasniqi, F.; Rudenko, A. [Max Planck Advanced Study Group at CFEL, Notkestrasse 85, 22607 Hamburg (Germany); Tschentscher, T. [European XFEL GmbH, Albert-Einstein-Ring 19, 22671 Hamburg (Germany); Stojanovic, N.; Duesterer, S.; Treusch, R.; Tolkiehn, M. [HASYLAB at DESY, Notkestrasse 85, 22607 Hamburg (Germany); Techert, S. [Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Goettingen (Germany); Max Planck Advanced Study Group at CFEL, Notkestrasse 85, 22607 Hamburg (Germany)

2012-11-01T23:59:59.000Z

218

Micrometeorological Modeling of Radiative and Convective Effects with a Building-Resolving Code  

Science Conference Proceedings (OSTI)

In many micrometeorological studies with computational fluid dynamics, building-resolving models usually assume a neutral atmosphere. Nevertheless, urban radiative transfers play an important role because of their influence on the energy budget. ...

Yongfeng Qu; Maya Milliez; Luc Musson-Genon; Bertrand Carissimo

2011-08-01T23:59:59.000Z

219

The Effects of Sunshine, Cloudiness and Haze on Received Ultraviolet Radiation in New York  

Science Conference Proceedings (OSTI)

Ultraviolet data from Rochester, Schenectady and Whiteface Mountain, New York, for the period November 1975-December 1977, have been studied to ascertain the importance of extraterrestrial ultraviolet (UV) radiation, sunshine, cloudiness and haze ...

Anita Baker-Blocker

1980-07-01T23:59:59.000Z

220

The Effects of Moist Convection and Water Vapor Radiative Processes on Climate Sensitivity  

Science Conference Proceedings (OSTI)

The primary interest of the present study is to examine the sensitivity of climate to radiative perturbations such as increases in CO2 and solar insolation for surface temperatures warmer than present day global averaged values (Ts> 290 K). The ...

M. Lal; V. Ramanathan

1984-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Low Dose Ionizing Radiation and HZE Particle Effects on Adult Hippocampal  

NLE Websites -- All DOE Office Websites (Extended Search)

and HZE Particle Effects on Adult Hippocampal and HZE Particle Effects on Adult Hippocampal Neurogenesis and mRNA Expression Kerry O'Banion University of Rochester School of Medicine & Dentistry Abstract Most of our knowledge about low dose radiation effects relates to DNA damage and chromosomal aberrations that result in cell death or alterations in genetic programs leading to malignancy. In addition To direct DNA damage, there is accumulating evidence that radiation induced alterations in the microenvironment can have significant effects on programs of cell replication and differentiation such as neurogenesis in adult mammalian brain. Adult neurogenesis in the hippocampus is postulated to play an important role in learning and memory and manipulations that alter neurogenesis, including inhibition following radiation exposure, have been

222

Study of Radiative and Turbulent Processes in the Stable Boundary Layer under Weak Wind Conditions  

Science Conference Proceedings (OSTI)

The role of radiation and turbulence was studied in a weak wind nocturnal inversion layer using a one-dimensional model. In contrast to a strong wind stable boundary layer where cooling within the surface inversion layer is dominated by ...

S. G. Gopalakrishnan; Maithili Sharan; R. T. McNider; M. P. Singh

1998-03-01T23:59:59.000Z

223

In Situ Study of Radiation Damage in Pure Zr and Zircaloy-2  

Science Conference Proceedings (OSTI)

Presentation Title, In Situ Study of Radiation Damage in Pure Zr and Zircaloy-2 ... cascades at the early stages of damage development at very low dose (0.01 ...

224

Radiation-induced leukemia: Comparative studies in mouse and man  

SciTech Connect

We now have a clear understanding of the mechanism by which radiation-induced (T-cell) leukemia occurs. In irradiated mice (radiation-induced thymic leukemia) and in man (acute lymphoblastic T-cell leukemia, T-ALL) the mechanism of leukemogenesis is surprisingly similar. Expressed in the most elementary terms, T-cell leukemia occurs when T-cell differentiation is inhibited by a mutation, and pre-T cells attempt but fail to differentiate in the thymus. Instead of leaving the thymus for the periphery as functional T-cells they continue to proliferate in the thymus. The proliferating pre- (pro-) T-cells constitute the (early) acute T-cell leukemia (A-TCL). This model for the mechanism of T-cell leukemogenesis accounts for all the properties of both murine and human A-TCL. Important support for the model has recently come from work by Ilan Kirsch and others, who have shown that mutations/deletions in the genes SCL (TAL), SIL, and LCK constitute primary events in the development of T-ALL, by inhibiting differentiation of thymic pre- (pro-) T-cells. This mechanism of T-cell leukemogenesis brings several specific questions into focus: How do early A-TCL cells progress to become potently tumorigenic and poorly treatable Is it feasible to genetically suppress early and/or progressed A-TCL cells What is the mechanism by which the differentiation-inhibited (leukemic) pre-T cells proliferate During the first grant year we have worked on aspects of all three questions.

Haas, M.

1991-01-01T23:59:59.000Z

225

Total aerosol effect: forcing or radiative flux perturbation?  

E-Print Network (OSTI)

of the ?rst indirect aerosol effect, Atmos. Chem. Phys. , 5,Cloud susceptibility and the ?rst aerosol indirect forcing:to black carbon and aerosol concentrations, J. Geophys.

Lohmann, Ulrike

2010-01-01T23:59:59.000Z

226

Low Dose Radiation Research Program: Mohan Natarajan  

NLE Websites -- All DOE Office Websites (Extended Search)

of Survival Advantage, Bystander Effect, and Genomic Instability after Low-LET Low Dose Radiation Exposure Funded Project Real-Time Molecular Study of Bystander Effect Using...

227

Radiation effects in MIT Lincoln Lab 3DIC technology  

E-Print Network (OSTI)

We characterized TID effects in MITLL 3DIC technology. We found that the effects were comparable for nFETs on the bottom tier with that on single tier wafers. Less positive charge build-up is observed for wide nFETs on the ...

Gouker, Pascale M.

228

Effect of Cloud Types on the Earth Radiation Budget Calculated with the ISCCP Cl Dataset: Methodology and Initial Results  

Science Conference Proceedings (OSTI)

A method is introduced to derive cloud effects on the earth radiation budget. The ISCCP Cl cloud data for daylight cases are used in combination with a radiative transfer model to estimate the outgoing broadband radiative fluxes at the top of the ...

C. Poetzsch-Heffter; Q. Liu; E. Ruperecht; C. Simmer

1995-04-01T23:59:59.000Z

229

Humidity effects on calibrations of radiation therapy electrometers  

SciTech Connect

Purpose: To eliminate variation in electrometer calibration results caused by high humidity and suboptimal connectors on the standard capacitors and to implement hardware that prevents overloading of the input stage of electrometers during calibration. Methods: A humidity-controlled cabinet was installed to provide a low-humidity environment for the standard capacitors. All of the coaxial BNC connections were replaced with Triax (TRB) connectors with the exception of the output from the voltage source. A three-stage RC filter with cascaded RC low-pass sections was designed and tested. Results: The installation of the humidity cabinet resulted in a major improvement in the stability and reproducibility of the electrometer calibration system. For the three years since this upgrade, the Ionizing Radiation Standards (IRS) electrometer calibration results have been consistent regardless of the ambient relative humidity in the lab. The connector replacements improved grounding in the calibration circuit. The three-stage filter allows the voltage at the output to rise in an S-shaped waveform, resulting in a smooth rise of the current through the isolation resistor from zero and back again, with no abrupt transition. For the filter design chosen, 99.99% of the charge is delivered within 6 s. Conclusions: A three-way improvement to the calibration measurement system was successful in eliminating the observed variations, resulting in an electrometer calibration measurement system that is unaffected by humidity and allowing reliable year-round calibrations of any electrometer encountered since the implementation of these changes.

Downton, B.; Walker, S. [Ionizing Radiation Standards, National Research Council of Canada, Bldg. M35, Ottawa, Ontario K1A 0R6 (Canada)

2012-02-15T23:59:59.000Z

230

Incorporating Radiation Effects into Edge Plasma Transport Models with Extended Atomic Data Tables  

DOE Green Energy (OSTI)

Plasmas at the tokamak edge can be very optically thick to hydrogen resonance lines. The resulting strong line radiation can significantly affect the ionization and energy balance in these plasmas. One method of account for effects is to self-consistently couple a partially ionized plasma transport model with a nonlocal thermodynamic equilibrium (NLTE) model incorporating line radiation transfer. This approach has been implemented in one dimension, but would be computationally challenging and expensive to implement in multiple dimensions. Approximate treatments of radiation transfer can decrease the computational time, but would still require coupling to a multidimensional plasma transport model to address realistic geometries, e.g. the tokamak divertor. Here, we consider the development of atomic hydrogen data tables that include radiation interactions and can be easily applied to multidimensional geometries.

Scott, H A; Adams, M L

2004-06-14T23:59:59.000Z

231

Low Dose Radiation Research Program: Slide Shows  

NLE Websites -- All DOE Office Websites (Extended Search)

Dose Health Effects of Radiation Health Effects of Radiation Adaptive Response to Low Dose Radiation PDF Background Radiation PDF Bystander Effects PDF Dirty Bombs PDF DNA Damage...

232

Low Dose Radiation Program: Radiation Biology and the Radiation Research  

NLE Websites -- All DOE Office Websites (Extended Search)

Biology and the Radiation Research Program Biology and the Radiation Research Program The Department of Energy (DOE) and its predecessor organizations, Energy Research and Development Agency (ERDA) and Atomic Energy Commission (AEC), always have been concerned about the health effects of ionizing radiation. Extensive research has been conducted under their sponsorship at all levels of biological organization from molecules to man. Over the past 60 years, studies using every type of radiation source have included exposure to both external radiation sources and to internally deposited radioactive materials. These exposures used different dose patterns and distributions delivered over a wide range of experimental times. This extensive research provided the basis for the new Low Dose Radiation Research Program, linking

233

Effects of solar UV radiation and climate change on biogeochemical cycling: Interactions and feedbacks  

SciTech Connect

Solar UV radiation, climate and other drivers of global change are undergoing significant changes and models forecast that these changes will continue for the remainder of this century. Here we assess the effects of solar UV radiation on biogeochemical cycles and the interactions of these effects with climate change, including feedbacks on climate. Such interactions occur in both terrestrial and aquatic ecosystems. While there is significant uncertainty in the quantification of these effects, they could accelerate the rate of atmospheric CO{sub 2} increase and subsequent climate change beyond current predictions. The effects of predicted changes in climate and solar UV radiation on carbon cycling in terrestrial and aquatic ecosystems are expected to vary significantly between regions. The balance of positive and negative effects on terrestrial carbon cycling remains uncertain, but the interactions between UV radiation and climate change are likely to contribute to decreasing sink strength in many oceanic regions. Interactions between climate and solar UV radiation will affect cycling of elements other than carbon, and so will influence the concentration of greenhouse and ozone-depleting gases. For example, increases in oxygen-deficient regions of the ocean caused by climate change are projected to enhance the emissions of nitrous oxide, an important greenhouse and ozone-depleting gas. Future changes in UV-induced transformations of aquatic and terrestrial contaminants could have both beneficial and adverse effects. Taken in total, it is clear that the future changes in UV radiation coupled with human-caused global change will have large impacts on biogeochemical cycles at local, regional and global scales.

Erickson III, David J [ORNL

2011-01-01T23:59:59.000Z

234

Radiation Tolerance Studies of BTeV Pixel Readout Chip Prototypes  

Science Conference Proceedings (OSTI)

We report on several irradiation studies performed on BTeV preFPIX2 pixel readout chip prototypes exposed to a 200 MeV proton beam at the Indiana University Cyclotron Facility. The preFPIX2 pixel readout chip has been implemented in standard 0.25 micron CMOS technology following radiation tolerant design rules. The tests confirmed the radiation tolerance of the chip design to proton total dose of 26 MRad. In addition, non destructive radiation-induced single event upsets have been observed in on-chip static registers and the single bit upset cross section has been measured.

Gabriele Chiodini et al.

2001-09-11T23:59:59.000Z

235

Total aerosol effect: forcing or radiative flux perturbation?  

E-Print Network (OSTI)

heterogeneous ice nucleation in mixed-phase clouds, Environ.interactions with mixed-phase and ice clouds can be comparedice nuclei for the indirect aerosol effect on stratiform mixed-phase

Lohmann, Ulrike

2010-01-01T23:59:59.000Z

236

Importance of Accurate Liquid Water Path for Estimation of Solar Radiation in Warm Boundary Layer Clouds: An Observational Study  

Science Conference Proceedings (OSTI)

A 1-yr observational study of overcast boundary layer stratus at the U.S. Department of Energy Atmospheric Radiation Measurement Program Southern Great Plains site illustrates that surface radiation has a higher sensitivity to cloud liquid water ...

Manajit Sengupta; Eugene E. Clothiaux; Thomas P. Ackerman; Seiji Kato; Qilong Min

2003-09-01T23:59:59.000Z

237

Types of Radiation Exposure  

NLE Websites -- All DOE Office Websites (Extended Search)

External Irradiation Contamination Incorporation Biological Effects of Acute, Total Body Irradiation Managing Radiation Emergencies Procedure Demonstration Types of radiation...

238

The Effect of the Water Vapor and Carbon Dioxide on the Radiation Absorption and Temperature Profile in Troposphere.  

E-Print Network (OSTI)

??The work on this paper focus on the effect of the water vapor and carbon dioxide on the absorption of atmospheric radiation and the temperature… (more)

Li, Chieh

2013-01-01T23:59:59.000Z

239

The whitehouse effect: shortwave radiative forcing of climate by anthropogenic aerosols  

SciTech Connect

Increases in atmospheric concentrations of carbon dioxide and other infrared active gases over the industrial period are thought to have increased the average flux of longwave (thermal infrared) radiation between the surface of the earth and the lower atmosphere, leading to an increase in global mean temperature. Over the same period it is though that concentrations of aerosol particles in the troposphere have similarly increased as a consequence of industrial emissions and that these increased concentrations of particles have increased the earth`s reflectivity of shortwave (solar) radiation incident on the planet both directly, by scattering radiation, and indirectly, by increasing the reflectivity of clouds. The term ``whitehouse effect`` is introduced to refer to this increased scattering of shortwave radiation by analogy to the term ``greenhouse effect,`` which refers to the enhanced trapping of longwave radiation resulting from increased concentrations of infrared active gases. Each of these phenomena is referred to as a ``forcing`` of the earth`s climate, that is a secular change imposed on the system; such a forcing is to be distinguished from a ``response`` of the system, such as a change in global mean temperature or other index of global climate. The forcing due to the direct and indirect effects induced by anthropogenic aerosols has been estimated to be comparable in global- average magnitude to that due to increased concentrations of greenhouse gases, but it is of opposite direction, that is exerting a cooling influence. The shortwave radiative influence of anthropogenic aerosols may thus be considered to be offsetting some, perhaps a great fraction, of the longwave radiative influence of anthropogenic greenhouse gases.

Schwartz, S.E.

1994-12-31T23:59:59.000Z

240

Combined effects of atomic radiation and other agents in Hiroshima and Nagasaki and possible application of fuzzy theory  

Science Conference Proceedings (OSTI)

The survivors of atomic bombings and those who visited Hiroshima and Nagasaki immediately after the atomic bombing could have been subjected to many other possible noxious effects in addition to atomic radiation. Various toxic substances must have been ... Keywords: Hiroshima, Nagasaki, atomic bombing, dose-effects relationships, fuzzy relation, hybrid numbers, lethal dose, radiation effects

Yasushi Nishiwaki; Hiroshi Matsuoka

2002-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

The effect of horizontal resolution on cloud radiative forcing in the ECMWF model. PCMDI report No. 22  

SciTech Connect

With expanding computer capability and capacity there has been considerable interest in increasing the resolution in GCMs. The primary driving force behind this are two fold: (1) increased resolution may reduce the systematic errors inherent in parameterization of sub-grid scale processes, and (2) higher resolution may improve confidence in regional scale studies of climatic features that are orographically influenced -- such as the effect of the Tibetan Plateau on the East Asian Monsoon. This study focuses on the effect of horizontal resolution on the spatial and temporal systematic errors of cloud radiative forcing and its components. In this paper, the top-of-the-atmosphere radiation fields are taken from a series of simulations using the European Centre for Medium Range Forecasts (ECMWF) general circulation model (cycle 33), run at four different horizontal resolutions. Section 2 discusses the concept of cloud radiative forcing and describes the simulations from the ECMWF model. The observed global field of cloud forcing from ERBE is presented in section 3 along with the model-produced fields of the net solar and longwave cloud forcing. The seasonal effect of forcing is described in section 4, and the results are summarized in section 5.

Potter, G.L.

1995-05-01T23:59:59.000Z

242

Radiation effects in beryllium used for plasma protection  

SciTech Connect

Beryllium is presently a leading candidate material for fusion reactor first wall coating and divertor applications. This paper reviews the literature on beryllium, emphasizing the effects of irradiation on essential properties. Swelling and embrittlement experiments as a function of irradiation temperature and dose, and as a function of neutron spectrum are described, and the results are quantified, where possible. Effects of impurity content are also reported, from which optimum composition specifications can be defined. Microstructural information has also been obtained to elucidate the processes controlling the property changes. The available information indicates that beryllium divertors can be expected to embrittle quickly and may need frequent replacement.

Gelles, D.S. [Pacific Northwest Lab., Richland, WA (United States); Dalle Donne, M. [Kernforschungszentrum Karlsruhe (Germany); Sernyaev, G.A. [SF NIKIET, Zarechnyi (Russian Federation); Kawamura, H. [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Blanket Irradiation and Analysis Lab.

1993-09-01T23:59:59.000Z

243

Contribution of radiation damage to the study of basic atomic motion in solids  

SciTech Connect

Radiation damage is a powerful tool for the study of point-defect interactions in solids. The large numbers of point defects produced during irradiation and subsequent annealing aggregate to form planar and linear defects. A study of the nature of these defects provides basic understanding of the mechanics of defect formation in solids. Defects in ion-bombarded silicon are studied using the transmission electron microscope. A mechanism for the formation of the observed defects is proposed. The utility of radiation damage studies in the understanding of atom motion in solids is demonstrated. (auth)

Seshan, K.

1973-02-01T23:59:59.000Z

244

Developing a Methodology for Characterizing the Effects of Building Materials’ Natural Radiation Background on a Radiation Portal Monitoring System  

E-Print Network (OSTI)

Trafficking of radioactive material, particularly special nuclear material (SNM), has long been a worldwide concern. To interdict this material the US government has installed radiation portal monitors (RPMs) around the globe. Building materials surrounding an RPM can greatly effect the detector’s background radiation levels due to Naturally Occurring Radioactive Material (NORM). In some cases this effect is so great that the initial RPM setup had to be rebuilt. This thesis develops a methodology for quick and efficient determination of the specific activity and composition of building materials surrounding a RPM to predict background levels, therefore determining the minimum detectable quantity (MDQ) of material. This methodology builds on previous work by Ryan et al by generating material and source cards for a detailed Monte Carlo N-Particle (MCNP) deck, based on an experimental RPM setup to predict the overall gamma background at a site. Gamma spectra were acquired from samples of building materials and analyzed to determine the specific activity of the samples. A code was developed to estimate the elemental composition of building materials using the gamma transmission of the samples. These results were compared to previous Neutron Activation Analysis (NAA) on the same samples. It was determined that densitometry provided an elemental approximation within 5% of that found through NAA. Using the specific activity and material composition, an MCNP deck was used to predict the gamma background levels in the detectors of a typical RPM. These results were compared against actual measurements at the RPM site, and shown to be within 10% of each other.

Fitzmaurice, Matthew Blake 1988-

2012-12-01T23:59:59.000Z

245

Human radiation studies: Remembering the early years. Oral history of biophysicist Cornelius A. Tobias, Ph.D., January 16, 1995  

SciTech Connect

Dr. Cornelius A. Tobias was interviewed by representatives of US DOE Office of Human Radiation Experiments (OHRE). He was chosen for this interview because of his extensive biophysics and medical physics research activities while he was employed by the University of California, Berkeley and San Francisco and at the Donner Laboratory. He discusses his involvement in wartime studies of effects of high altitude on aviators, carbon monoxide with radioactive tracers, blood studies with radioactive iron, human use committees, heavy-ion research with the Bevatron, boron isotope research, classified research involving human subjects, heavy-particle radiography, heavy- particle beams and medical research, and pituitary irradiation studies,.

1995-07-01T23:59:59.000Z

246

MECHANISTIC STUDY OF LOW DOSE RADIATION INDUCED PROTEOLYTIC CASCADES  

NLE Websites -- All DOE Office Websites (Extended Search)

Cells organize into tissue-like structures which recapitulate the intact human mammary gland morphology (Figure 1) enabling molecular level study of how normal tissues respond...

247

Computer simulation and topological modeling of radiation effects in zircon  

E-Print Network (OSTI)

The purpose of this study is to understand on atomic level the structural response of zircon (ZrSiO4) to irradiation using molecular dynamics (MD) computer simulations, and to develop topological models that can describe ...

Zhang, Yi, 1979-

2006-01-01T23:59:59.000Z

248

Radiation-cooled Dew Water Condensers Studied by Computational Fluid Dynamic (CFD)  

E-Print Network (OSTI)

Harvesting condensed atmospheric vapour as dew water can be an alternative or complementary potable water resource in specific arid or insular areas. Such radiation-cooled condensing devices use already existing flat surfaces (roofs) or innovative structures with more complex shapes to enhance the dew yield. The Computational Fluid Dynamic - CFD - software PHOENICS has been programmed and applied to such radiation cooled condensers. For this purpose, the sky radiation is previously integrated and averaged for each structure. The radiative balance is then included in the CFD simulation tool to compare the efficiency of the different structures under various meteorological parameters, for complex or simple shapes and at various scales. It has been used to precise different structures before construction. (1) a 7.32 m^2 funnel shape was studied; a 30 degree tilted angle (60 degree cone half-angle) was computed to be the best compromise for funnel cooling. Compared to a 1 m^2 flat condenser, the cooling efficienc...

Clus, O; Muselli, M; Nikolayev, Vadim; Sharan, Girja; Beysens, D

2007-01-01T23:59:59.000Z

249

Radiation: Radiation Control (Indiana)  

Energy.gov (U.S. Department of Energy (DOE))

It is the policy of the state to encourage the constructive uses of radiation and to control its harmful effects. This section contains regulations pertaining to the manufacture, use,...

250

What can be learned from epidemiologic studies of persons exposed to low doses of radiation?  

SciTech Connect

The main objective of radiation risk assessment is to determine the risk of various adverse health effects associated with exposure to low doses and low dose rates. Extrapolation of risks from studies of persons exposed at high doses (generally exceeding 1 Sv) and dose rates has been the primary approach used to achieve this objective. The study of Japanese atomic bomb survivors in Hiroshima and Nagasaki has played an especially important role in risk assessment efforts. A direct assessment of the dose-response function based on studies of persons exposed at low doses and dose rates is obviously desirable. This paper focuses on the potential of both current and future nuclear workers studies for investigating the dose-response functions at low doses, and also discusses analyses making use of the low dose portion of the atomic bomb survivor data. Difficulties in using these data are the statistical imprecision of estimated dose-response parameters, and potential bias resulting from confounding factors and from uncertainties in dose estimates.

Gilbert, E.S.

1993-04-01T23:59:59.000Z

251

Radiation effects on resins and zeolites at Three Mile Island Unit II  

DOE Green Energy (OSTI)

Radiation effects on resin and zeolite used in the waste cleanup at Three Mile Island Unit II have been examined both experimentally and in-situ. Hydrogen and organic gases are generated due to absorbed radiation as a function of resin material, curie loading and residual water content. Significant oxygen scavaging was demonstrated in the organic resin liners. Hydrogen and oxygen gases in near stoichiometric quantities are generated from irradiation of residual water in inorganic zeolites. Gas generation was determined to be directly proportional to curie content but correlates poorly with residual water content in zeolite vessels. Results of the gas generation analyses of EPICOR II liners show that vessels with less than 166 curies had almost no hydrogen generated during two years of storage and therefore did not require safety measures for shipment or storage. Experimental measurements done at research laboratories predicted similar results associated with hydrogen gas generation and oxygen depletion. X-ray diffraction examinations and ion exchange capacity measurements indicated no evidence of irradiation effects on the structure or cesium exchange capacity for zeolites exposed to 10/sup 10/ rads. Darkening and damage of organic resin due to radiation has been identified. Breaking and agglomeration of the purification demineralizer resin is believed to be the result of temperature effects. No damage was identified from radiation effects on zeolite. Organic and inorganic sorbents used in the processing of contaminated waters at TMI-2 have been shown to be effective in maintaining long-term stability under high radiation conditions. The effects of radiolytic degradation have been shown by direct measurements and simulation tests and are of use in their general application throughout the industry.

Reilly, J.K.; Grant, P.J.; Quinn, G.J.; Hofstetter, K.J.

1984-01-01T23:59:59.000Z

252

THE EFFECTS OF RADIATION AND RADIOISOTOPES ON THE LIFE PROCESSES. An Annotated Bibliography  

SciTech Connect

Issued in two books and an Index. A total of 11,944 annotated references is presented to report and published literature concerning the effects of radiation on biological systems. Abstracts are included for many references. Author and subject indexes are included. (C.H.)

Pierce, C.M. comp.

1963-09-01T23:59:59.000Z

253

PAPERS PREPARED FOR RADIATION EFFECTS REVIEW MEETING, CONGRESS HOTEL, CHICAGO, JULY 31-AUGUST 1, 1956  

SciTech Connect

Research in radiation effects on reactor materials is reviewed in ten papers presented by representatives of Oak Ridge National Laboratory, General Electric Company, knolls Atomic Power Laboratory, Dattelle Memorial Institute, Brookhaven Nationaal Laboratory, Argonne National Laboratory, Bettis Plant, and Atomic Power Development Associates. Separate abstracts have been prepared for each paper. (T.R.H.)

1956-08-01T23:59:59.000Z

254

Determination of Effective Emittance and a Radiatively Equivalent Microphysical Model of Cirrus from Ground-Based and Satellite Observations during the International Cirrus Experiment: The 18 October 1989 Case Study  

Science Conference Proceedings (OSTI)

Ground-based observations and satellite data have been compared for the 18 October 1989 case study of the International Cirrus Experiment (ICE) field campaign. They correspond to thin cirrus clouds with infrared emittances in the range 0–0.3. ...

G. Brogniez; J. C. Buriez; V. Giraud; F. Parol; C. Vanbauce

1995-04-01T23:59:59.000Z

255

LOW-LEVEL RADIATION HEALTH EFFECTS: PROGRAMS AND PANEL DISCUSSION  

E-Print Network (OSTI)

accident. The report of the Soviet Union to the International Atomic Energy Agency experts' meeting plutonium had been produced in reactors and separated for bomb production for -40 yr (Ref. 1 OBTAINED SO FAR The Russians have been studying cohorts 5, 6, and 7 for 30 yr and have several reports

Shlyakhter, Ilya

256

The Radiative Effects of Clouds and their Impact on Climate  

Science Conference Proceedings (OSTI)

Our knowledge of the direct role of clouds in long-term climate change is examined in an overview of key results published over the last 15 or 20 years, along with some relevant unpublished model studies. The focus is on 1) the impact of clouds ...

Albert Arking

1991-06-01T23:59:59.000Z

257

Vertical distribution and radiative effects of mineral dust and biomass burning aerosol over West Africa during DABEX  

SciTech Connect

This paper presents measurements of the vertical distribution of aerosol extinction coefficient over West Africa, during the Dust and Biomass burning aerosol Experiment (DABEX) / African Monsoon Multidisciplinary Analysis dry season Special Observing period zero (AMMA-SOP0). In situ aircraft measurements from the UK FAAM aircraft are compared with two ground based lidars (POLIS and ARM MPL) and an airborne lidar on an ultra-light aircraft. In general mineral dust was observed at low altitudes (up to 2km) and a mixture of biomass burning aerosol and dust was observed at altitudes of 2-5km. The study exposes difficulties associated with spatial and temporal variability when inter-comparing aircraft and ground measurements. Averaging over many profiles provided a better means of assessing consistent errors and biases associated with in situ sampling instruments and retrievals of lidar ratios. Shortwave radiative transfer calculations and a 3-year simulation with the HadGEM2-A climate model show that the radiative effect of biomass burning aerosol is somewhat sensitive to the vertical distribution of aerosol. Results show a 15% increase in absorption of solar radiation by elevated biomass burning aerosol when the observed low-level dust layer is included as part of the background atmospheric state in the model. This illustrates that the radiative forcing of anthropogenic absorbing aerosol is sensitive to the treatment of other aerosol species and that care is needed in simulating natural aerosols assumed to exist in the pre-industrial, or natural state of the atmosphere.

Johnson, Ben; Heese, B.; McFarlane, Sally A.; Chazette, P.; Jones, A.; Bellouin, N.

2008-09-12T23:59:59.000Z

258

Integrated Experimental and Computational Approach to Understand the Effects of Heavy Ion Radiation on Skin Homeostasis.  

SciTech Connect

The effects of low dose high linear energy transfer (LET) radiation on human health are of concern for both space and clinical exposures. As epidemiological data for such radiation exposures are scarce for making relevant predictions, we need to understand the mechanism of response especially in normal tissues. Our objective here is to understand the effects of heavy ion radiation on tissue homeostasis in a realistic model system. Towards this end, we exposed an in vitro three dimensional skin equivalent to low fluences of Neon (Ne) ions (300 MeV/u), and determined the differentiation profile as a function of time following exposure using immunohistochemistry. We found that Ne ion exposures resulted in transient increases in the tissue regions expressing the differentiation markers keratin 10, and filaggrin, and more subtle time-dependent effects on the number of basal cells in the epidermis. We analyzed the data using a mathematical model of the skin equivalent, to quantify the effect of radiation on cell proliferation and differentiation. The agent-based mathematical model for the epidermal layer treats the epidermis as a collection of heterogeneous cell types with different proliferation/differentiation properties. We obtained model parameters from the literature where available, and calibrated the unknown parameters to match the observed properties in unirradiated skin. We then used the model to rigorously examine alternate hypotheses regarding the effects of high LET radiation on the tissue. Our analysis indicates that Ne ion exposures induce rapid, but transient, changes in cell division, differentiation and proliferation. We have validated the modeling results by histology and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The integrated approach presented here can be used as a general framework to understand the responses of multicellular systems, and can be adapted to other epithelial tissues.

von Neubeck, Claere; Shankaran, Harish; Geniza, Matthew; Kauer, Paula M.; Robinson, Robert J.; Chrisler, William B.; Sowa, Marianne B.

2013-08-08T23:59:59.000Z

259

Cloud-radiative effects on implied oceanic energy transports as simulated by atmospheric general circulation models  

DOE Green Energy (OSTI)

This paper reports on energy fluxes across the surface of the ocean as simulated by fifteen atmospheric general circulation models in which ocean surface temperatures and sea-ice boundaries are prescribed. The oceanic meridional energy transport that would be required to balance these surface fluxes is computed, and is shown to be critically sensitive to the radiative effects of clouds, to the extent that even the sign of the Southern Hemisphere ocean energy transport can be affected by the errors in simulated cloud-radiation interactions.

Gleckler, P.J. [Lawrence Livermore National Lab., CA (United States); Randall, D.A. [Colorado State Univ., Fort Collins, CO (United States); Boer, G. [Canadian Climate Centre, Victoria (Canada)

1994-03-01T23:59:59.000Z

260

Evaluating WRF-Chem multi-scale model in simulating aerosol radiative properties over the tropics – A case study over India  

Science Conference Proceedings (OSTI)

We utilized WRF-Chem multi-scale model to simulate the regional distribution of aerosols, optical properties and its effect on radiation over India for a winter month. The model is evaluated using measurements obtained from upper-air soundings, AERONET sun photometers, various satellite instruments, and pyranometers operated by the Indian Meteorological Department. The simulated downward shortwave flux was overestimated when the effect of aerosols on radiation and clouds was neglected. Downward shortwave radiation from a simulation that included aerosol-radiation interaction processes was 5 to 25 Wm{sup -2} closer to the observations, while a simulation that included aerosol-cloud interaction processes were another 1 to 20 Wm{sup -2} closer to the observations. For the few observations available, the model usually underestimated particulate concentration. This is likely due to turbulent mixing, transport errors and the lack of secondary organic aerosol treatment in the model. The model efficiently captured the broad regional hotspots such as high aerosol optical depth over Indo-Gangetic basin as well as the northwestern and southern part of India. The regional distribution of aerosol optical depth compares well with AVHRR aerosol optical depth and the TOMS aerosol index. The magnitude and wavelength-dependence of simulated aerosol optical depth was also similar to the AERONET observations across India. Differences in surface shortwave radiation between simulations that included and neglected aerosol-radiation interactions were as high as -25 Wm{sup -2}, while differences in surface shortwave radiation between simulations that included and neglect aerosol-radiation-cloud interactions were as high as -30 Wm{sup -2}. The spatial variations of these differences were also compared with AVHRR observation. This study suggests that the model is able to qualitatively simulate the impact of aerosols on radiation over India; however, additional measurements of particulate mass and composition are needed to fully evaluate whether the aerosol precursor emissions are adequate when simulating radiative forcing in the region.

Seethala, C.; Pandithurai, G.; Fast, Jerome D.; Polade, Suraj D.; Reddy, M. S.; Peckham, Steven E.

2012-01-24T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

A Prospective Cohort Study on Radiation-induced Hypothyroidism: Development of an NTCP Model  

Science Conference Proceedings (OSTI)

Purpose: To establish a multivariate normal tissue complication probability (NTCP) model for radiation-induced hypothyroidism. Methods and Materials: The thyroid-stimulating hormone (TSH) level of 105 patients treated with (chemo-) radiation therapy for head-and-neck cancer was prospectively measured during a median follow-up of 2.5 years. Hypothyroidism was defined as elevated serum TSH with decreased or normal free thyroxin (T4). A multivariate logistic regression model with bootstrapping was used to determine the most important prognostic variables for radiation-induced hypothyroidism. Results: Thirty-five patients (33%) developed primary hypothyroidism within 2 years after radiation therapy. An NTCP model based on 2 variables, including the mean thyroid gland dose and the thyroid gland volume, was most predictive for radiation-induced hypothyroidism. NTCP values increased with higher mean thyroid gland dose (odds ratio [OR]: 1.064/Gy) and decreased with higher thyroid gland volume (OR: 0.826/cm{sup 3}). Model performance was good with an area under the curve (AUC) of 0.85. Conclusions: This is the first prospective study resulting in an NTCP model for radiation-induced hypothyroidism. The probability of hypothyroidism rises with increasing dose to the thyroid gland, whereas it reduces with increasing thyroid gland volume.

Boomsma, Marjolein J.; Bijl, Hendrik P.; Christianen, Miranda E.M.C.; Beetz, Ivo; Chouvalova, Olga; Steenbakkers, Roel J.H.M. [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Laan, Bernard F.A.M. van der [Department of Otorhinolaryngology/Head and Neck Surgery, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Wolffenbuttel, Bruce H.R. [Department of Endocrinology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Endocrinology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Oosting, Sjoukje F. [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Schilstra, Cornelis [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Langendijk, Johannes A., E-mail: j.a.langendijk@umcg.nl [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)

2012-11-01T23:59:59.000Z

262

Radiative QCD corrections a personal outlook  

E-Print Network (OSTI)

We describe several problems related to the studies of the effects of radiative QCD corrections in the phenomenological and theoretical considerations thus summarizing the work of the QCD part of the Symposium on "Radiative Corrections: Status and Outlook".

Kataev, A L

1994-01-01T23:59:59.000Z

263

Radiative QCD Corrections: A Personal Outlook  

E-Print Network (OSTI)

We describe several problems related to the studies of the effects of radiative QCD corrections in the phenomenological and theoretical considerations thus summarizing the work of the QCD part of the Symposium on "Radiative Corrections: Status and Outlook".

Andrei L. Kataev

1994-10-18T23:59:59.000Z

264

A Climatology of Surface Cloud Radiative Effects at the ARM Tropical Western Pacific Sites  

SciTech Connect

Cloud radiative effects on surface downwelling fluxes are investigated using long-term datasets from the three Atmospheric Radiation Measurement (ARM) sites in the Tropical Western Pacific (TWP) region. The Nauru and Darwin sites show significant variability in sky cover, downwelling radiative fluxes, and surface cloud radiative effect (CRE) due to El Niño and the Australian monsoon, respectively, while the Manus site shows little intra-seasonal or interannual variability. Cloud radar measurement of cloud base and top heights are used to define cloud types so that the effect of cloud type on the surface CRE can be examined. Clouds with low bases contribute 71-75% of the surface shortwave (SW) CRE and 66-74% of the surface longwave (LW) CRE at the three TWP sites, while clouds with mid-level bases contribute 8-9% of the SW CRE and 12-14% of the LW CRE, and clouds with high bases contribute 16-19% of the SW CRE and 15-21% of the LW CRE.

McFarlane, Sally A.; Long, Charles N.; Flaherty, Julia E.

2013-04-01T23:59:59.000Z

265

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

SciTech Connect

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

Serrato, M.

2010-01-29T23:59:59.000Z

266

Radiation Damage Study in Natural Zircon Using Neutrons Irradiation  

Science Conference Proceedings (OSTI)

Changes of atomic displacements in crystalline structure of natural zircon (ZrSiO{sub 4}) can be studied by using neutron irradiation on the surface of zircon and compared the data from XRD measurements before and after irradiation. The results of neutron irradiation on natural zircon using Pneumatic Transfer System (PTS) at PUSPATI TRIGA Research Reactor in the Malaysian Nuclear Agency are discussed in this work. The reactor produces maximum thermal power output of 1 MWatt and the neutron flux of up to 1x10{sup 13} ncm{sup -2}s{sup -1}. From serial decay processes of uranium and thorium radionuclides in zircon crystalline structure, the emission of alpha particles can produce damage in terms of atomic displacements in zircon. Hence, zircon has been extensively studied as a possible candidate for immobilization of fission products and actinides.

Lwin, Maung Tin Moe; Amin, Yusoff Mohd.; Kassim, Hasan Abu [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Mohamed, Abdul Aziz [Materials Technology Group, Industrial Technology Division, Malaysian Nuclear Agency Bangi, 43000 Kajang, Selangor Darul Ehsan (Malaysia); Karim, Julia Abdul [Reactor Physics Section, Nuclear Power Division, Malaysian Nuclear Agency Bangi, 43000 Kajang, Selangor Darul Ehsan (Malaysia)

2011-03-30T23:59:59.000Z

267

Experimental Studies on Coherent Synchrotron Radiation at an Emittance Exchange Beamline  

SciTech Connect

One of the goals of the Fermilab A0 photoinjector is to experimentally investigate the transverse to longitudinal emittance exchange (EEX) principle. Coherent synchrotron radiation in the emittance exchange line could limit the performance of the emittance exchanger at short bunch lengths. In this paper, we present experimental and simulation studies of the coherent synchrotron radiation (CSR) in the emittance exchange line at the A0 photoinjector. We report on time-resolved CSR studies using a skew-quadrupole technique. We also demonstrate the advantages of running the EEX with an energy chirped beam.

Thangaraj, J.C.T.; Thurman-Keup, R.; Ruan, J.; Johnson, A.S.; Lumpkin, A.H.; Santucci, J.; /Fermilab

2012-04-01T23:59:59.000Z

268

THE BEIR-III REPORT AND THE HEALTH EFFECTS OF LOW-LEVEL RADIATION  

E-Print Network (OSTI)

Protection Against Ionizing Radiation from External Sources,Protection Against Ionizing Radiation from External Sources:induction by ionizing radiation. Brit. J. Radiol. 51: 401-

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

269

Cherenkov Radiation from e+e- Pairs and Its Effect on nu e Induced Showers  

E-Print Network (OSTI)

5] J. V. Jelley, Cherenkov Radiation and its applications (calculated the Cherenkov radiation from e + e ? pairs as a? 2 [1?? 2 ?(?)]), the radiation is suppressed compared to

Mandal, Sourav K.; Klein, Spencer R.; Jackson, J. David

2005-01-01T23:59:59.000Z

270

Biology Studies  

NLE Websites -- All DOE Office Websites (Extended Search)

Studies Radiation biologists study the effect of radiation on living tissue. This field, which has direct analogies to the SEE studies, looks at the damage sustained by cells in...

271

Radiation Tolerant Metallic Multilayers  

Science Conference Proceedings (OSTI)

Strategies that can alleviate radiation damage may assist the design of radiation tolerant materials. We will summarize our recent studies on radiation damage in ...

272

Mutation, radiation, and species survival: The genetics studies of the Atomic Bomb Casualty Commission in Hiroshima and Nagasaki, Japan  

SciTech Connect

This is an analysis of the work of the Atomic Bomb Casualty Commission, an American agency which studied the effects of radiation on survivors of the atomic bombings at Hiroshima and Nagasaki, Japan, 1947-1975. Funded by the U.S. Atomic Energy Commission and directed by the National Academy of Sciences-National Research Council, the ABCC was the largest and longest medical study of the estimated 300,000 survivors. The morphological genetics study dominated the ABCCs first decade. James Neel and his principal collaborator William J. Schull tracked more than 76,000 pregnancies. Their results (1956) suggested the bombs radiation had no detectable impact on the offspring of survivors. Though geneticists knew that radiation caused heritable mutations in experimental organisms such as Drosophila, and believed it caused mutations in humans, the Neel-Schull findings were not a surprise. The practical difficulties of the study, and the relatively small increase in abnormal births to be expected, made a finding of significant effects unlikely. The Neel-Schull approach reflected the scientific debate over genetic load, and the Muller-Dobzhansky classical-balance controversy. Yet the findings also reflected the post-war debate over atomic energy and weapons testing. Many extra-scientific forces militated against a finding of positive effects at Hiroshima and Nagasaki. Negative findings were consistent with the needs of the Atomic Energy Commission, the State Department and the U.S. military. This dissertation explores how both the scientific debate about genetic load, and the political debate about atmospheric weapons testing, shaped this complex epidemiological study.

Lindee, M.S.

1990-01-01T23:59:59.000Z

273

Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells in Response to Low Dose Ionizing Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells in Response to Low Dose Ionizing Radiation Deok-Jin Jang 1 , Mingquan Guo 1 , Julia S.F.Chu 2 , Kyle T. Kurpinski 2 , Bjorn Rydberg 1 , Song Li 2 , and Daojing Wang 1 1. Life Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720 2. Department of Bioengineering, University of California, Berkeley, CA 94720 We will present data obtained during the first year of our DOE/NASA Low Dose Radiation Research program. We utilized a comprehensive approach including transcriptomics, proteomics, phosphoproteomics, and biochemistry to characterize human mesenchymal stem cells (MSCs) in response to low dose ionizing radiation. We first determined the cell survival, proliferation, and osteogenic differentiation of

274

Environmental radiation protection studies related to nuclear industries, using AMS  

Science Conference Proceedings (OSTI)

14 C is produced in nuclear reactors during normal operation and part of it is continuously released into the environment. Because of the biological importance of carbon and the long physical half-life of 14 C it is of interest to study these releases. The 14 C activity concentrations in the air and vegetation around some Swedish as well as foreign nuclear facilities have been measured by accelerator mass spectrometry (AMS). 59 Ni is produced by neutron activation in the stainless steel close to the core of a nuclear reactor. The 59 Ni levels have been measured in order to be able to classify the different parts of the reactor with respect to their content of long-lived radionuclides before final storage. The technique used to measure 59 Ni at a small accelerator such as the Lund facility has been developed over the past few years and material from the Swedish nuclear industry has been analyzed.

Ragnar Hellborg; Bengt Erlandsson; Mikko Faarinen; Helena Håkansson; Kjell Håkansson; Madis Kiisk; Carl-Erik Magnusson; Per Persson; Göran Skog; Kristina Stenström; Sören Mattsson; Charlotte Thornberg

2001-01-01T23:59:59.000Z

275

A Three-Dimensional Radiative Transfer Model to Investigate the Solar Radiation within a Cloudy Atmosphere. Part I: Spatial Effects  

Science Conference Proceedings (OSTI)

A new Monte Carlo–based three-dimensional (3D) radiative transfer model of high spectral and spatial resolution is presented. It is used to investigate the difference in broadband solar radiation absorption, top-of-the-atmosphere upwelling, and ...

William O’Hirok; Catherine Gautier

1998-06-01T23:59:59.000Z

276

A Three-Dimensional Radiative Transfer Model to Investigate the Solar Radiation within a Cloudy Atmosphere. Part II: Spectral Effects  

Science Conference Proceedings (OSTI)

In this second part of a two-part paper, the spectral response of the interaction between gases, cloud droplets, and solar radiation is investigated using a Monte Carlo-based three-dimensional (3D) radiative transfer model with a spectral ...

William O’Hirok; Catherine Gautier

1998-10-01T23:59:59.000Z

277

Neutron measurements and radiation damage calculations for fusion materials studies  

SciTech Connect

Fusion reactors will generate intense neutron fields, especially at the inner surfaces of containment vessels. With a typical wall loading of 1 MW/m/sup 2/, the yearly neutron fluence will be about 10/sup 26/ n/m/sup 2/. In a material like stainless steel this irradiation will produce about 10 atomic displacements-per-atom (DPA), 100 appM helium, 500 appM hydrogen, and various other transmutations. The gas-to-DPA ratios are very high compared to fission reactors due to the 14 MeV neutrons from the d-t fusion reaction. No existing neutron source can produce both the high fluence and high gas rates needed to simulate fusion damage. Consequently, fusion material studies are underway in a variety of facilities including fission reactors and accelerator-based neutron sources. A Subtask Group has been created by DOE to characterize these diverse facilities in terms of neutron flux and energy spectrum and to calculate DPA and transmutation for specific irradiations. Material property changes can then be correlated between facilities and extrapolated to fusion reactor conditions.

Greenwood, L.R.

1983-01-01T23:59:59.000Z

278

Oxy-fuel combustion of coal and biomass, the effect on radiative and convective heat transfer and burnout  

Science Conference Proceedings (OSTI)

This paper focuses on results of co-firing coal and biomass under oxy-fuel combustion conditions on the RWEn 0.5 MWt Combustion Test Facility (CTF). Results are presented of radiative and convective heat transfer and burnout measurements. Two coals were fired: a South African coal and a Russian Coal under air and oxy-fuel firing conditions. The two coals were also co-fired with Shea Meal at a co-firing mass fraction of 20%. Shea Meal was also co-fired at a mass fraction of 40% and sawdust at 20% with the Russian Coal. An IFRF Aerodynamically Air Staged Burner (AASB) was used. The thermal input was maintained at 0.5 MWt for all conditions studied. The test matrix comprised of varying the Recycle Ratio (RR) between 65% and 75% and furnace exit O{sub 2} was maintained at 3%. Carbon-in-ash samples for burnout determination were also taken. Results show that the highest peak radiative heat flux and highest flame luminosity corresponded to the lowest recycle ratio. The effect of co-firing of biomass resulted in lower radiative heat fluxes for corresponding recycle ratios. Furthermore, the highest levels of radiative heat flux corresponded to the lowest convective heat flux. Results are compared to air firing and the air equivalent radiative and convective heat fluxes are fuel type dependent. Reasons for these differences are discussed in the main text. Burnout improves with biomass co-firing under both air and oxy-fuel firing conditions and burnout is also seen to improve under oxy-fuel firing conditions compared to air. (author)

Smart, John P.; Patel, Rajeshriben; Riley, Gerry S. [RWEnpower, Windmill Hill Business Park, Whitehill Way, Swindon, Wiltshire SN5 6PB, England (United Kingdom)

2010-12-15T23:59:59.000Z

279

Quantitative Ultrasonic Evaluation of Radiation-Induced Late Tissue Toxicity: Pilot Study of Breast Cancer Radiotherapy  

Science Conference Proceedings (OSTI)

Purpose: To investigate the use of advanced ultrasonic imaging to quantitatively evaluate normal-tissue toxicity in breast-cancer radiation treatment. Methods and Materials: Eighteen breast cancer patients who received radiation treatment were enrolled in an institutional review board-approved clinical study. Radiotherapy involved a radiation dose of 50.0 to 50.4 Gy delivered to the entire breast, followed by an electron boost of 10.0 to 16.0 Gy delivered to the tumor bed. Patients underwent scanning with ultrasound during follow-up, which ranged from 6 to 94 months (median, 22 months) postradiotherapy. Conventional ultrasound images and radio-frequency (RF) echo signals were acquired from treated and untreated breasts. Three ultrasound parameters, namely, skin thickness, Pearson coefficient, and spectral midband fit, were computed from RF signals to measure radiation-induced changes in dermis, hypodermis, and subcutaneous tissue, respectively. Ultrasound parameter values of the treated breast were compared with those of the untreated breast. Ultrasound findings were compared with clinical assessment using Radiation Therapy Oncology Group (RTOG) late-toxicity scores. Results: Significant changes were observed in ultrasonic parameter values of the treated vs. untreated breasts. Average skin thickness increased by 27.3%, from 2.05 {+-} 0.22mm to 2.61 {+-} 0.52mm; Pearson coefficient decreased by 31.7%, from 0.41 {+-} 0.07 to 0.28 {+-} 0.05; and midband fit increased by 94.6%, from -0.92 {+-} 7.35 dB to 0.87 {+-} 6.70 dB. Ultrasound evaluations were consistent with RTOG scores. Conclusions: Quantitative ultrasound provides a noninvasive, objective means of assessing radiation-induced changes to the skin and subcutaneous tissue. This imaging tool will become increasingly valuable as we continue to improve radiation therapy technique.

Liu Tian, E-mail: tliu34@emory.ed [Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA (United States); Zhou Jun [Department of Radiation Oncology, Columbia University Medical Center, New York, NY (United States); Yoshida, Emi J. [Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA (United States); Woodhouse, Shermian A. [Department of Radiation Oncology, Columbia University Medical Center, New York, NY (United States); Schiff, Peter B. [Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA (United States); Wang, Tony J.C. [Department of Radiation Oncology, Columbia University Medical Center, New York, NY (United States); Lu Zhengfeng; Pile-Spellman, Eliza [Department of Radiology, Columbia University Medical Center, New York, NY (United States); Zhang Pengpeng [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Kutcher, Gerald J. [Department of History, Binghamton University, Binghamton, NY (United States)

2010-11-01T23:59:59.000Z

280

System level latchup mitigation for single event and transient radiation effects on electronics  

DOE Patents (OSTI)

A `blink` technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection means, power dump logic means, and energy limiting measures with autonomous recovery. The event detection means includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation or by ion-induced destructive latchup of a semiconductor device. The current sensing means is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation. The power dump means includes power dump logic means having a first input terminal connected to the output terminal of the ionizing radiation pulse detection means and having a second input terminal connected to the output terminal of the current sensing means. The power dump logic means provides an output signal to the input terminal of the means for opening the power bus and the means for shorting the power bus to a ground potential to remove power from the power bus. The energy limiting mean with autonomous recovery includes means for opening the power bus and means for shorting the power bus to a ground potential. The means for opening the power bus and means for shorting the power bus to a ground potential includes a series FET and a shunt FET. The invention provides for self-contained sensing for latchup, first removal of power to protect latched components, and autonomous recovery to enable transparent operation of other system elements.

Kimbrough, J.R.; Colella, N.J.

1994-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

System level latchup mitigation for single event and transient radiation effects on electronics  

DOE Patents (OSTI)

A ``blink`` technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection circuitry, power dump logic circuitry, and energy limiting measures with autonomous recovery. The event detection circuitry includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation. The current sensing circuitry is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation or by ion-induced destructive latchup of a semiconductor device. The power dump circuitry includes power dump logic circuitry having a first input terminal connected to the output terminal of the ionizing radiation pulse detection circuitry and having a second input terminal connected to the output terminal of the current sensing circuitry. The power dump logic circuitry provides an output signal to the input terminal of the circuitry for opening the power bus and the circuitry for shorting the power bus to a ground potential to remove power from the power bus. The energy limiting circuitry with autonomous recovery includes circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential. The circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential includes a series FET and a shunt FET. The invention provides for self-contained sensing for latchup, first removal of power to protect latched components, and autonomous recovery to enable transparent operation of other system elements. 18 figs.

Kimbrough, J.R.; Colella, N.J.

1997-09-30T23:59:59.000Z

282

System level latchup mitigation for single event and transient radiation effects on electronics  

DOE Patents (OSTI)

A "blink" technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection circuitry, power dump logic circuitry, and energy limiting measures with autonomous recovery. The event detection circuitry includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation. The current sensing circuitry is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation or by ion-induced destructive latchup of a semiconductor device. The power dump circuitry includes power dump logic circuitry having a first input terminal connected to the output terminal of the ionizing radiation pulse detection circuitry and having a second input terminal connected to the output terminal of the current sensing circuitry. The power dump logic circuitry provides an output signal to the input terminal of the circuitry for opening the power bus and the circuitry for shorting the power bus to a ground potential to remove power from the power bus. The energy limiting circuitry with autonomous recovery includes circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential. The circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential includes a series FET and a shunt FET. The invention provides for self-contained sensing for latchup, first removal of power to protect latched components, and autonomous recovery to enable transparent operation of other system elements.

Kimbrough, Joseph Robert (Pleasanton, CA); Colella, Nicholas John (Livermore, CA)

1997-01-01T23:59:59.000Z

283

Health effects models for nuclear power plant accident consequence analysis: Modifications of models resulting from recent reports on health effects of ionizing radiation  

Science Conference Proceedings (OSTI)

The Nuclear Regulatory Commission has sponsored several studies to identify and quantify the potential health effects of accidental releases of radionuclides from nuclear power plants. The most recent health effects models resulting from these efforts were published in two reports, NUREG/CR-4214, Rev. 1, Part 1 (1990) and Part 2 (1989). Several major health effects reports have been published recently that may impact the health effects models presented in these reports. This addendum to the Part 2 (1989) report, provides a review of the 1986 and 1988 reports by the United Nations Scientific Committee on the Effects of Atomic Radiation, the National Academy of Sciences/National Research Council BEAR 5 Committee report and Publication 60 of the International Commission on Radiological Protection as they relate to this report. The three main sections of this addendum discuss early occurring and continuing effects, late somatic effects, and genetic effects. The major changes to the NUREG/CR-4214 health effects models recommended in this addendum are for late somatic effects. These changes reflect recent changes in cancer risk factors that have come from longer followup and revised dosimetry in major studies like that on the Japanese A-bomb survivors. The results presented in this addendum should be used with the basic NUREG/CR-4214 reports listed above to obtain the most recent views on the potential health effects of radionuclides released accidentally from nuclear power plants. 48 refs., 4 figs., 24 tabs.

Abrahamson, S. (Wisconsin Univ., Madison, WI (United States)); Bender, M.A. (Brookhaven National Lab., Upton, NY (United States)); Boecker, B.B.; Scott, B.R. (Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States). Inhalation Toxicology Research Inst.); Gilbert, E.S. (Pacific Northwest Lab., Richland, WA (United States))

1991-08-01T23:59:59.000Z

284

Computational study of atmospheric transfer radiation on an equatorial tropical desert (La Tatacoa, Colombia)  

E-Print Network (OSTI)

Radiative transfer models explain and predict interaction between solar radiation and the different elements present in the atmosphere, which are responsible for energy attenuation. In Colombia there have been neither measurements nor studies of atmospheric components such as gases and aerosols that can cause turbidity and pollution. Therefore satellite images cannot be corrected radiometrically in a proper way. When a suitable atmospheric correction is carried out, loss of information is avoided, which may be useful for discriminating image land cover. In this work a computational model was used to find radiative atmospheric attenuation (300 1000nm wavelength region) on an equatorial tropical desert (La Tatacoa, Colombia) in order to conduct an adequate atmospheric correction.

Delgado-Correal, Camilo; Castaño, Gabriel

2012-01-01T23:59:59.000Z

285

Failure Mode and Effect Analysis for Delivery of Lung Stereotactic Body Radiation Therapy  

SciTech Connect

Purpose: To improve the quality and safety of our practice of stereotactic body radiation therapy (SBRT), we analyzed the process following the failure mode and effects analysis (FMEA) method. Methods: The FMEA was performed by a multidisciplinary team. For each step in the SBRT delivery process, a potential failure occurrence was derived and three factors were assessed: the probability of each occurrence, the severity if the event occurs, and the probability of detection by the treatment team. A rank of 1 to 10 was assigned to each factor, and then the multiplied ranks yielded the relative risks (risk priority numbers). The failure modes with the highest risk priority numbers were then considered to implement process improvement measures. Results: A total of 28 occurrences were derived, of which nine events scored with significantly high risk priority numbers. The risk priority numbers of the highest ranked events ranged from 20 to 80. These included transcription errors of the stereotactic coordinates and machine failures. Conclusion: Several areas of our SBRT delivery were reconsidered in terms of process improvement, and safety measures, including treatment checklists and a surgical time-out, were added for our practice of gantry-based image-guided SBRT. This study serves as a guide for other users of SBRT to perform FMEA of their own practice.

Perks, Julian R., E-mail: julian.perks@ucdmc.ucdavis.edu [University of California Davis Medical Center, Sacramento, CA (United States); Stanic, Sinisa; Stern, Robin L.; Henk, Barbara; Nelson, Marsha S.; Harse, Rick D.; Mathai, Mathew; Purdy, James A.; Valicenti, Richard K.; Siefkin, Allan D.; Chen, Allen M. [University of California Davis Medical Center, Sacramento, CA (United States)

2012-07-15T23:59:59.000Z

286

Radiation effects in 1. 06-. mu. m InGaAs LED's and Si photodiodes  

SciTech Connect

Because of the low-intrinsic and radiation-induced attenuation losses in glass fibers in the wavelength range 1.0--1.3 ..mu..m, emitters and detectors operating in this range are of practical importance for radiation-environment applications. We have studied the effects of both ..gamma.. and neutron irradiation on the properties of InGaAs LED's emitting at 1.06 ..mu..m and Si photodiode detectors optimized for this wavelength. While the preirradiation light output of the InGaAs LED's is low relative to many GaAs LED's, the InGaAs devices exhibit less sensitivity to radiation than the most radiation-hardened GaAs LED's. No significant neutron-induced light-output degradation is observed below 1 x 10/sup 13/ n/cm/sup 2/, while 2 x 10/sup 7/ Co-60 rads are required before any ..gamma..-induced degradation is observed. In addition, a significant portion of the ..gamma..-induced light-output degradation can be recovered by applying forward-bias currents of the order of 50 mA in magnitude. Although ..gamma.. irradiation up to 2 x 10/sup 8/ rads has essentially no effect on the photodiodes, neutron fluences above 2 x 10/sup 14/ n/cm/sup 2/ cause a reduction in responsivity. Analysis of the neutron-induced increases in the photodiode leakage current with the guard ring attached reveals a lifetime-damage constant product of 4 x 10/sup -12/ cm/sup 2//n. Laboratory isolators made up of these emitters and detectors have typical preirradiation current-transfer ratios of 5 x 10/sup -4/ which decrease by a factor of 10 after an irradiation of 1.5 x 10/sup 14/ n/cm/sup 2/.

Barnes, C.E.

1979-08-01T23:59:59.000Z

287

Prepulse effect on laser-induced water-window radiation from a liquid nitrogen jet  

E-Print Network (OSTI)

is schematically shown in Fig. 1. A high-purity nitrogen gas was cooled and liquefied through the cooling stagesPrepulse effect on laser-induced water-window radiation from a liquid nitrogen jet J. Son,a M. Cho.3­4.4 nm x ray from a liquid nitrogen jet. It is observed that a prepulse of only 2 mJ enhances

Kim, Jae-Hoon

288

The whitehouse effect: Shortwave radiative forcing of climate by anthropogenic aerosols, an overview  

E-Print Network (OSTI)

Abstraet--Loadings of tropospheric aerosols have increased substantially over the past 150 yr as a consequence of industrial activities. These aerosols enhance reflection of solar radiation by the Earth-atmosphere system both directly, by scattering light in clear air and, indirectly, by increasing the reflectivity of clouds. The magnitude of the resultant decrease in absorption of solar radiation is estimated to be comparable on global average to the enhancement in infrared forcing at the tropopause due to increases in concentrations of CO2 and other greenhouse gases over the same time period. Estimates of the aerosol shortwave forcing are quite uncertain, by more than a factor of two about the current best estimates. This article reviews the atmospheric chemistry and microphysical processes that govern the loading and light scattering properties of the aerosol particles responsible for the direct effect and delineates the basis for the present estimates of the magnitude and uncertainty in the resultant radiative forcing. The principal sources of uncertainty are in the loading of anthropogenic aerosols, which is highly variable spatially and temporally because of the relatively short residence time of these aerosols (ca. 1 week) and the episodic removal in precipitation, and in the dependence of light scattering on particle size, and in turn on relative humidity. Uncertainty in aerosol forcing is the greatest source of uncertainty in radiative forcing of climate

Stephen E. Schwartz

1996-01-01T23:59:59.000Z

289

A two dimensional modeling study of the sensitivity of ozone to radiative flux uncertainties  

Science Conference Proceedings (OSTI)

Radiative processes strongly effect equilibrium trace gas concentrations both directly, through photolysis reactions, and indirectly through temperature and transport processes. We have used the LLNL 2-D chemical-radiative-transport model to investigate the net sensitivity of equilibrium ozone concentrations to several changes in radiative forcing. Doubling CO/sub 2/ from 300 ppmv to 600 ppmv resulted in a temperature decrease of 5 K to 8 K in the middle stratosphere along with an 8% to 16% increase in ozone in the same region. Replacing our usual shortwave scattering algorithms with a simplified Rayleigh algorithm led to a 1% to 2% increase in ozone in the lower stratosphere. Finally, modifying our normal CO/sub 2/ cooling rates by corrections derived from line-by-line calculations resulted in several regions of heating and cooling. We observed temperature changes on the order of 1 K to 1.5 K with corresponding changes of 0.5% to 1.5% in O/sub 3/. Our results for doubled CO/sub 2/ compare favorably with those by other authors. Results for our two perturbation scenarios stress the need for accurately modeling radiative processes while confirming the general validity of current models. 15 refs., 5 figs.

Grant, K.E.; Wuebbles, D.J.

1988-08-01T23:59:59.000Z

290

Highlights in Radiation Research - A Timeline  

NLE Websites -- All DOE Office Websites (Extended Search)

survivors. 1947 Atomic Bomb Casualty Commission (ABCC) created to study the biological effects of radiation on Japanese atomic bomb survivors. Brookhaven National Laboratory...

291

Do heavy ions induce the bystander effect? : study to determine the induction of the bystander effect from Fe ion beam compared to X-rays in human keratinocytes  

E-Print Network (OSTI)

The bystander effect is the observation that non-irradiated cells near a cell traversed by radiation express biological responses such as micronuclei formation and genomic instability. Most published studies of the bystander ...

Anzenberg, Vered

2005-01-01T23:59:59.000Z

292

Radiation effects at a high power accelerator and applications to advanced energy sources  

Science Conference Proceedings (OSTI)

Many materials are exposed to atom-displacing radiation at high-power accelerators such as the Los Alamos Meson Physics Facility (LAMPF). Beam current densities in the 800-MeV proton beam vary from 12.5 mA cm{sup {minus}2} (8 {times} 10{sup 16} p/cm{sup 2}s) on graphite targets to 20-{mu}A cm{sup {minus}2} (1.3 {times} 10{sup 14} p/cm{sup 2}s) on metal-alloy windows. High-level radiation damage results from these particle fluxes. As a consequence of secondary-particle generation in targets and windows and low-level beam losses that lead to particle interactions with structural material, various components are exposed to low-level proton fluxes, gamma radiation, and neutron fluxes of 10{sup 6}--10{sup 10} n/cm{sup 2}s. These include vacuum seals and vacuum chambers of stainless steel and aluminum alloys, solid-state devices for control, diagnostic, and data acquisition electronics, closed-loop cooling-water systems, and insulators. Properties of these materials are degraded by the radiation exposure. Studies of LAMPF and other accelerators, however, have produced solutions to materials problems, allowing the machines to operate for acceptable times without failure. Nevertheless, additional improvements are being investigated in order to further improve operational reliability and safety. 25 refs., 3 figs., 3 tabs.

Sommer, W.F.; Garner, F.A.; Brown, R.D.; Wechsler, M.S. (Los Alamos National Lab., NM (USA); Battelle Pacific Northwest Lab., Richland, WA (USA); Los Alamos National Lab., NM (USA); Iowa State Univ. of Science and Technology, Ames, IA (USA))

1989-01-01T23:59:59.000Z

293

RADIATION SAFETY POLICY Effective Date: April 4, 2012 Originating Office: Office of the  

E-Print Network (OSTI)

radiation exposure "As Low as Reasonably Achievable" "Internal Radiation Permit" ("IRP") means and the general public from unnecessary or potentially harmful levels of radiation exposure. PURPOSE capable of generating X or Gamma radiation "Radiology" involves external exposure of humans to Radiation

Doedel, Eusebius

294

Radiation effects on MOS devices: dosimetry, annealing, irradiation sequence and sources  

Science Conference Proceedings (OSTI)

This paper reports on some investigations of dosimetry, annealing, irradiation sequences, and radioactive sources, involved in the determination of radiation effects on MOS devices. Results show that agreement in the experimental and theoretical surface to average doses support the use of thermo-luminescent dosimeters (manganese activated calcium fluoride) in specifying the surface dose delivered to thin gate insulators of MOS devices. Annealing measurements indicate the existence of at least two energy levels, or activation energies, for recovery of soft oxide MOS devices after irradiation by electrons, protons, and gammas. Damage sensitivities of MOS devices were found to be independent of combinations and sequences of radiation type or energies. Comparison of various gamma sources indicated a small dependence of damage sensitivity on the Cobalt facility, but a more significant dependence in the case of the Cesium source. These results were attributed to differences in the spectral content of the several sources.

Stassinopoulos, E.; Brucker, G.; Gunten, O.; Jordan, T.; Knudson, A.

1983-06-01T23:59:59.000Z

295

Finite Duration and Energy Effects in Lorentz-Violating Vacuum Cerenkov Radiation  

E-Print Network (OSTI)

Vacuum Cerenkov radiation is possible in certain Lorentz-violating quantum field theories, when very energetic charges move faster than the phase speed of light. In the presence of a CPT-even, Lorentz-violating modification of the photon sector, the character of the Cerenkov process is controlled by the high-frequency behavior of the radiation spectrum. The development of the Cerenkov process can be markedly different, depending on whether the only limits on the emission of very energetic photons come from energy-momentum conservation or whether there are additional effects that cut off the spectrum at high frequencies. Moreover, since the high-frequency cutoff determines the total rate at which an emitting charge loses energy, it also controls all aspects of the emission that are related to the process's finite duration.

Brett Altschul

2007-09-27T23:59:59.000Z

296

The Radiative Effects of Aerosols on Photochemical Smog: Measurements and Modeling  

E-Print Network (OSTI)

. High concentrations of both ozone and aerosols are observed in the eastern United States during stagnant weather conditions associated with transport from the W or NW; they show similar spatial and temporal patterns. We discuss a causal mechanism that may contribute to this correlation - the radiative effects of aerosols on photolysis rates. We measured j(NO 2 ), the rate coefficient for nitrogen dioxide photolysis, and column aerosol optical depths at NASA/Goddard Space Flight Center in Greenbelt, MD (39.01 ffi N and 76.87 ffi W) during the smog seasons of 1995 and 1997. Direct measurements and radiative transfer model calculations show that particles can reduce surface j(NO 2 ) by 5 - 60%, depending on solar zenith angle and aerosol loading. Although particle scattering by dense aerosol loading on smoggy days decreases near-surface photolysis rates, it increases the integrated boundary layer photolysis rates by up to 20% and leads to accelerated photochemical smog formation in ...

Kondragunta Dickerson Stenchikov; S. Kondragunta; R. R. Dickerson; G. Stenchikov; W. F. Ryan; B. Holben; R. W. Stewart

2000-01-01T23:59:59.000Z

297

Effects of radiation exposure on SRL 131 composition glass in a steam environment  

Science Conference Proceedings (OSTI)

Monoliths of SRL 131 borosilicate glass were irradiated in a saturated air-steam environment, at temperatures of 150{degree}C, to examine the effects of radiation on nuclear waste glass behavior. Half of the tests used actinide and Tc-99 doped glass and were exposed to an external ionizing gamma source, while the remaining glass samples were doped only with uranium and were reacted without any external radiation exposure. The effects of radiation exposure on glass alteration and secondary phase formation were determined by comparing the reaction rates and mineral paragenesis of the two sets of samples. All glass samples readily reacted with the water that condensed on their surfaces, producing a smectite clay layer within the first three days of testing. Additional crystalline phases precipitated on the altered glass surface with increasing reaction times, including zeolites, smectite, calcium and sodium silicates, phosphates, evaporitic salts, and uranyl silicates. Similar phases were produced on both the nonirradiated and irradiated samples; however, the quantity of precipitates was increased and the rate of paragenetic sequence development was accelerated in the latter. After 56 days of testing, the smectite layer developed at an average rate of {approximately}0.16 and 0.63 {mu}m/day for the nonirradiated and irradiated samples, respectively. These comparisons indicate that layer development is accelerated approximately four-fold due to the radiation exposure at high glass surface area/liquid volume (SA/V) conditions. This increase apparently occurs in response to the rapid concentration of radiolytic products, including nitric acid, in the thin films of water contacting the sample monoliths.

Wronkiewicz, D.J.; Bradley, C.R.; Bates, J.K. [Argonne National Lab., IL (United States); Wang, L.M. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Geology

1993-11-01T23:59:59.000Z

298

Thermal Effects of Rotation in Random Classical Zero-Point Radiation  

E-Print Network (OSTI)

The rotating reference system, two-point correlation functions, and energy density are used as the basis for investigating thermal effects observed by a detector rotating through random classical zero-point radiation. The RS consists of Frenet -Serret orthogonal tetrads where the rotating detector is at rest and has a constant acceleration vector. The CFs and the energy density at the rotating reference system should be periodic with rotation period because CF and energy density measurements is one of the tools the detector can use to justify the periodicity of its motion. The CFs have been calculated for both electromagnetic and massless scalar fields in two cases, with and without taking this periodicity into consideration. It turned out that only periodic CFs have some thermal features and particularly the Planck's factor with the temperature T= h w /k . Regarding to the energy density of both electromagnetic and massless scalar field it is shown that the detector rotating in the zero-point radiation observes not only this original zero-point radiation but, above that, also the radiation which would have been observed by an inertial detector in the thermal bath with the Plank's spectrum at the temperature T. This effect is masked by factor 2/3(4 gamma^2-1) for the electromagnetic field and 2/9 (4 gamma ^2-1) for the massless scalar field, where the Lorentz factor gamma=(1 - v^2 / c^2)^(1/2). Appearance of these masking factors is connected with the fact that rotation is defined by two parameters, angular velocity w and the radius of rotation, in contrast with a uniformly accelerated linear motion which is defined by only one parameter, acceleration a. Our calculations involve classical point of view only and to the best of our knowledge these results have not been reported in quantum theory yet.

Yefim S. Levin

2007-04-27T23:59:59.000Z

299

The Effect of Realistic Radiative Transfer on Potential Vorticity Structures, Including the Influence of Background Shear and Strain  

Science Conference Proceedings (OSTI)

A modified version of the radiation scheme of Shine is used to investigate the decay of small-scale potential vorticity structures characteristic of those observed in the lower and middle stratosphere. Following Fels, effective thermal damping ...

P. H. Haynes; W. E. Ward

1993-10-01T23:59:59.000Z

300

Effects of Ionizing Radiation on Digital Single Event Transients in a 180-nm Fully Depleted SOI Process  

E-Print Network (OSTI)

Effects of ionizing radiation on single event transients are reported for Fully Depleted SOI (FDSOI) technology using experiments and simulations. Logic circuits, i.e. CMOS inverter chains, were irradiated with cobalt-60 ...

Keast, Craig L.

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

The effects of imposed stratospheric cooling on the maximum intensity of tropical cyclones in axisymmetric radiative-convective equilibrium  

Science Conference Proceedings (OSTI)

The effects of stratospheric cooling and sea surface temperature (SST) warming on tropical cyclone (TC) potential intensity (PI) are explored using an axisymmetric cloud-resolving model run to radiative-convective equilibrium (RCE). Almost all ...

Hamish A. Ramsay

302

The Sensitivity of the Radiation Budget in a Climate Simulation to Neglecting the Effect of Small Ice Particles  

Science Conference Proceedings (OSTI)

The sensitivity of the atmospheric radiation budget to ignoring small ice particles (D ? 100 ?m) in parameterization of the mean effective size of ice particles was investigated by using the Canadian Centre for Climate Modelling and Analysis (...

Faisal S. Boudala; George A. Isaac; N. A. McFarlane; J. Li

2007-07-01T23:59:59.000Z

303

Geant4 applications in the heliospheric radiation environment  

E-Print Network (OSTI)

The high energy ionizing radiation environment in the solar system consists of three main sources: the radiation belts, galactic cosmic rays and solar energetic particles. Geant4 is a Monte Carlo radiation transport simulation toolkit, with applications in areas as high energy physics, nuclear physics, astrophysics or medical physics research. In this poster, Geant4 applications to model and study the effects of the heliospheric radiation environment are presented. Specific applications are being developed to study the effect of the radiation environment on detector components, to describe the response and to optimise the design of radiation monitors for future space missions and to predict the radiation environment in Mars surface, orbits and moons.

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

2007-09-11T23:59:59.000Z

304

A Study of Fitting the Generalized Lambda Distribution to Solar Radiation Data  

Science Conference Proceedings (OSTI)

The increased interest in the climatology of solar radiation dictates a need for a distribution to fit daily solar radiation totals which tend to have negatively-skewed probability distributions. Even daily mean solar radiation for weekly periods ...

A. Öztürk; R. F. Dale

1982-07-01T23:59:59.000Z

305

Radiation Effects of n-type, Low Resistivity, Spiral Silicon Drift Detector Hybrid Systems  

Science Conference Proceedings (OSTI)

We have developed a new thin-window, n-type, low-resistivity, spiral silicon drift detector (SDD) array - to be used as an extraterrestrial X-ray spectrometer (in varying environments) for NASA. To achieve low-energy response, a thin SDD entrance window was produced using a previously developed method. These thin-window devices were also produced on lower resistivity, thinner, n-type, silicon material, effectively ensuring their radiation hardness in anticipation of operation in potentially harsh radiation environments (such as found around the Jupiter system). Using the Indiana University Cyclotron Facility beam line RERS1, we irradiated a set of suitable diodes up to 5 Mrad and the latest iteration of our ASICs up to 12 Mrad. Then we irradiated two hybrid detectors consisting of newly, such-produced in-house (BNL) SDD chips bonded with ASICs with doses of 0.25 Mrad and 1 Mrad. Also we irradiated another hybrid detector consisting of previously produced (by KETEK) on n-type, high-resistivity SDD chip bonded with BNL's ASICs with a dose of 1 Mrad. The measurement results of radiated diodes (up to 5 Mrad), ASICs (up to 12 Mrad) and hybrid detectors (up to 1 Mrad) are presented here.

Chen W.; De Geronimo G.; Carini, G.A.; Gaskin, J.A.; Keister, J.W.; Li, S.; Li, Z.; Ramsey, B.D.; Siddons, D.P.; Smith, G.C.; Verbitskaya, E.

2011-11-15T23:59:59.000Z

306

Treatment Effects and Sequelae of Radiation Therapy for Orbital Mucosa-Associated Lymphoid Tissue Lymphoma  

SciTech Connect

Purpose: Among extranodal lymphomas, orbital mucosa-associated lymphoid tissue (MALT) lymphoma is a relatively rare presentation. We performed a review to ascertain treatment efficacy and toxicity of radiation therapy for orbital MALT lymphoma. We also evaluated changes in visual acuity after irradiation. Methods and Materials: Thirty patients with orbital MALT lymphoma underwent radiation therapy with curative intent. Clinical stages at diagnosis were stage I{sub E}A in 29 patients and stage II{sub E}A in 1 patient. Total doses of 28.8 to 45.8 Gy (median, 30 Gy) in 15 to 26 fractions (median, 16 fractions) were delivered to the tumors. Results: All irradiated tumors were controlled during the follow-up period of 2 to 157 months (median, 35 months) after treatment. Two patients had relapses that arose in the cervical lymph node and the ipsilateral palpebral conjunctiva outside the radiation field at 15 and 67 months after treatment, respectively. The 5-year local progression-free and relapse-free rates were 100% and 96%, respectively. All 30 patients are presently alive; the overall and relapse-free survival rates at 5 years were 100% and 96%, respectively. Although 5 patients developed cataracts of grade 2 at 8 to 45 months after irradiation, they underwent intraocular lens implantation, and their eyesight recovered. Additionally, there was no marked deterioration in the visual acuity of patients due to irradiation, with the exception of cataracts. No therapy-related toxicity of grade 3 or greater was observed. Conclusions: Radiation therapy was effective and safe for patients with orbital MALT lymphoma. Although some patients developed cataracts after irradiation, visual acuity was well preserved.

Hata, Masaharu, E-mail: mhata@syd.odn.ne.jp [Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan); Omura, Motoko; Koike, Izumi [Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan); Tomita, Naoto [Department of Internal Medicine and Clinical Immunology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan); Iijima, Yasuhito [Department of Ophthalmology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan); Tayama, Yoshibumi; Odagiri, Kazumasa; Minagawa, Yumiko [Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan); Ogino, Ichiro [Department of Radiation Oncology, Yokohama City University Medical Center, Yokohama, Kanagawa (Japan); Inoue, Tomio [Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan)

2011-12-01T23:59:59.000Z

307

Program on Technology Innovation: Evaluation of Updated Research on the Health Effects and Risks Associated with Low-Dose Ionizing Radiation  

Science Conference Proceedings (OSTI)

The Electric Power Research Institute (EPRI) has performed a systematic review of recently published, peer-reviewed scientific studies in the fields of epidemiology and radiobiology that discuss health risks associated with exposure to low levels of ionizing radiation. As a result of this study, the EPRI team concludes that there is a need to re-evaluate the magnitude of dose and dose-rate effectiveness factors (DDREF), including the significant body of radiobiology data that suggests non-linear risks at...

2009-11-18T23:59:59.000Z

308

Why does the Unruh effect rely on Lorentz invariance, while Hawking radiation does not ?  

E-Print Network (OSTI)

We show that without Lorentz invariance, the Unruh effect does not exist. We use modified dispersion relations and describe in turn: the non-thermal nature of the vacuum (defined in the preferred frame) restricted to the Rindler wedge, the loss of the KMS property of the Wigthman function, the transition amplitudes and transition rates of a uniformaly accelerated detector. This situation seems to contrast with the Hawking radiation of acoustic black holes, which under certain assumptions has been shown to be robust to a breaking of Lorentz symmetry. We explain this discrepancy.

Campo, David

2010-01-01T23:59:59.000Z

309

Radiation Risk from Chronic Low Dose-Rate Radiation Exposures: The Role of Life-Time Animal Studies - Workshop October 2005  

SciTech Connect

As a part of Radiation research conference, a workshop was held on life-long exposure studies conducted in the course of irradiation experiements done at Argonne National Laboratory between 1952-1992. A recent review article documents many of the issues discussed at that workshop.

Gayle Woloschak

2009-12-16T23:59:59.000Z

310

Structural Stability of Human Fibroblast Growth Factor-1 Is Essential for Protective Effects Against Radiation-Induced Intestinal Damage  

Science Conference Proceedings (OSTI)

Purpose: Human fibroblast growth factor-1 (FGF1) has radioprotective effects on the intestine, although its structural instability limits its potential for practical use. Several stable FGF1 mutants were created increasing stability in the order, wild-type FGF1, single mutants (Q40P, S47I, and H93G), Q40P/S47I, and Q40P/S47I/H93G. This study evaluated the contribution of the structural stability of FGF1 to its radioprotective effect. Methods and Materials: Each FGF1 mutant was administered intraperitoneally to BALB/c mice in the absence of heparin 24 h before or after total body irradiation (TBI) with {gamma}-rays at 8-12 Gy. Several radioprotective effects were examined in the jejunum. Results: Q40P/S47I/H93G could activate all subtypes of FGF receptors in vitro much more strongly than the wild-type without endogenous or exogenous heparin. Preirradiation treatment with Q40P/S47I/H93G significantly increased crypt survival more than wild-type FGF1 after TBI at 10 or 12 Gy, and postirradiation treatment with Q40P/S47I/H93G was effective in promoting crypt survival after TBI at 10, 11, or 12 Gy. In addition, crypt cell proliferation, crypt depth, and epithelial differentiation were significantly promoted by postirradiation treatment with Q40P/S47I/H93G. The level of stability of FGF1 mutants correlated with their mitogenic activities in vitro in the absence of heparin; however, preirradiation treatment with the mutants increased the crypt number to almost the same level as Q40P/S47I/H93G. When given 24 h after TBI at 10 Gy, all FGF1 mutants increased crypt survival more than wild-type FGF1, and Q40P/S47I/H93G had the strongest mitogenic effects in intestinal epithelial cells after radiation damage. Moreover, Q40P/S47I/H93G prolonged mouse survival after TBI because of the repair of intestinal damage. Conclusion: These findings suggest that the structural stability of FGF1 can contribute to the enhancement of protective effects against radiation-induced intestinal damage. Therefore, Q40P/S47I/H93G is pharmacologically one of the most promising candidates for clinical applications for radiation-induced gastrointestinal syndrome.

Nakayama, Fumiaki, E-mail: f_naka@nirs.go.jp [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan)] [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Umeda, Sachiko [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan)] [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Yasuda, Takeshi [Department of Radiation Emergency Medicine, Research Center for Radiation Emergency Medicine, National Institute of Radiological Sciences, Chiba (Japan)] [Department of Radiation Emergency Medicine, Research Center for Radiation Emergency Medicine, National Institute of Radiological Sciences, Chiba (Japan); Asada, Masahiro; Motomura, Kaori; Suzuki, Masashi [Signaling Molecules Research Laboratory, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki (Japan)] [Signaling Molecules Research Laboratory, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki (Japan); Zakrzewska, Malgorzata [Faculty of Biotechnology, University of Wroclaw (Poland)] [Faculty of Biotechnology, University of Wroclaw (Poland); Imamura, Toru [Signaling Molecules Research Laboratory, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki (Japan)] [Signaling Molecules Research Laboratory, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki (Japan); Imai, Takashi [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan)] [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan)

2013-02-01T23:59:59.000Z

311

"Nuclear Lighthouse Effect"Studies Win BESSY Prize  

NLE Websites -- All DOE Office Websites (Extended Search)

9th, 2003 9th, 2003 "Nuclear Lighthouse Effect" Studies Win BESSY Prize A new technique for high-resolution x-ray scattering spectroscopy developed at the Advanced Photon Source has garnered an award for innovation in synchrotron radiation research. Ralf Röhlsberger, Professor of Physics at the Technische Universitaet Muenchen, is a recipient of the "Innovationspreis Synchrotronstrahlung 2002" ("Innovation Prize in Synchrotron Radiation 2002") prize awarded annually by the Friends of BESSY. The award, which honors "new developments in the field that provide access to and use of synchrotron radiation," was presented for Röhlsberger's "groundbreaking work in the nuclear resonant scattering of synchrotron radiation," the so-called "Nuclear Lighthouse Effect," a method

312

Human radiation studies: Remembering the early years. Oral history of biochemist John Randolph Totter, Ph.D., January 23, 1995  

SciTech Connect

This document is a transcript of an interview of Dr. John Randolph Tottler by representatives of the US DOE Office of Human Radiation Experiments. Dr. Tottler was selected for this interview because of his career with the Atomic Energy Commission Division of Biology and Medicine (DBM), particularly as its director from 1967 to 1972. After a short biographical sketch Dr. Tottler discusses his remembrances on a wide range topics including nucleic acid and leukemia research at Oak Ridge, AEC biochemistry training in South America, DBM`s research focus on radiation effects, early leadership of DBM, relations with the US Public Health Service, controversies on low-level radiation, iodine from fallout, on John Gofman, and Project Plowshare, funding for AEC Research Programs and for international research, testicular irradiation of prisoners in Washington State and Oregon, Plutonium injections, ethics of government radiation research, and opinions of public misperceptions about radiation and cancer.

1995-09-01T23:59:59.000Z

313

Cloud Scavenging Effects on Aerosol Radiative and Cloud-nucleating Properties - Final Technical Report  

Science Conference Proceedings (OSTI)

The optical properties of aerosol particles are the controlling factors in determining direct aerosol radiative forcing. These optical properties depend on the chemical composition and size distribution of the aerosol particles, which can change due to various processes during the particles’ lifetime in the atmosphere. Over the course of this project we have studied how cloud processing of atmospheric aerosol changes the aerosol optical properties. A counterflow virtual impactor was used to separate cloud drops from interstitial aerosol and parallel aerosol systems were used to measure the optical properties of the interstitial and cloud-scavenged aerosol. Specifically, aerosol light scattering, back-scattering and absorption were measured and used to derive radiatively significant parameters such as aerosol single scattering albedo and backscatter fraction for cloud-scavenged and interstitial aerosol. This data allows us to demonstrate that the radiative properties of cloud-processed aerosol can be quite different than pre-cloud aerosol. These differences can be used to improve the parameterization of aerosol forcing in climate models.

Ogren, John A.; Sheridan, Patrick S.; Andrews, Elisabeth

2009-03-05T23:59:59.000Z

314

Epidemiology of accidental radiation exposures  

Science Conference Proceedings (OSTI)

Much of the information on the health effects of radiation exposure available to date comes from long-term studies of the atomic bombings in Hiroshima and Nagasaki. Accidental exposures, such as those resulting from the Chernobyl and Kyshtym accidents, have as yet provided little information concerning health effects of ionizing radiation. This paper will present the current state of our knowledge concerning radiation effects, review major large-scale accidental exposures and the types of studies that are needed. 64 refs., 3 tabs.

Cardis, E. [International Agency for Research on Cancer, Lyon (France)

1996-05-01T23:59:59.000Z

315

Development and Validation of a Heart Atlas to Study Cardiac Exposure to Radiation Following Treatment for Breast Cancer  

SciTech Connect

Purpose: Cardiac toxicity is an important sequela of breast radiotherapy. However, the relationship between dose to cardiac structures and subsequent toxicity has not been well defined, partially due to variations in substructure delineation, which can lead to inconsistent dose reporting and the failure to detect potential correlations. Here we have developed a heart atlas and evaluated its effect on contour accuracy and concordance. Methods and Materials: A detailed cardiac computed tomography scan atlas was developed jointly by cardiology, cardiac radiology, and radiation oncology. Seven radiation oncologists were recruited to delineate the whole heart, left main and left anterior descending interventricular branches, and right coronary arteries on four cases before and after studying the atlas. Contour accuracy was assessed by percent overlap with gold standard atlas volumes. The concordance index was also calculated. Standard radiation fields were applied. Doses to observer-contoured cardiac structures were calculated and compared with gold standard contour doses. Pre- and post-atlas values were analyzed using a paired t test. Results: The cardiac atlas significantly improved contour accuracy and concordance. Percent overlap and concordance index of observer-contoured cardiac and gold standard volumes were 2.3-fold improved for all structures (p < 0.002). After application of the atlas, reported mean doses to the whole heart, left main artery, left anterior descending interventricular branch, and right coronary artery were within 0.1, 0.9, 2.6, and 0.6 Gy, respectively, of gold standard doses. Conclusions: This validated University of Michigan cardiac atlas may serve as a useful tool in future studies assessing cardiac toxicity and in clinical trials which include dose volume constraints to the heart.

Feng, Mary, E-mail: maryfeng@umich.ed [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Moran, Jean M. [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Koelling, Todd [Department of Internal Medicine, Division of Cardiology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Chughtai, Aamer [Department of Radiology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Chan, June L.; Freedman, Laura; Hayman, James A.; Jagsi, Reshma; Jolly, Shruti; Larouere, Janice; Soriano, Julie; Marsh, Robin; Pierce, Lori J. [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States)

2011-01-01T23:59:59.000Z

316

Analytical and experimental studies of heat pipe radiation cooling of hypersonic propulsion systems  

SciTech Connect

Preliminary, research-oriented, analytical and experimental studies were completed to assess the feasibility of using high-temperature heat pipes to cool hypersonic engine components. This new approach involves using heat pipes to transport heat away from the combustor, nozzle, or inlet regions, and to reject it to the environment by thermal radiation from an external heat pipe nacelle. For propulsion systems using heat pipe radiation cooling (HPRC), it is possible to continue to use hydrocarbon fuels into the Mach 4 to Mach 6 speed range, thereby enhancing the economic attractiveness of commercial or military hypersonic flight. In the second-phase feasibility program recently completed, we found that heat loads produced by considering both convection and radiation heat transfer from the combustion gas can be handled with HPRC design modifications. The application of thermal insulation to ramburner and nozzle walls was also found to reduce the heat load by about one-half and to reduce peak HPRC system temperatures to below 2700{degrees}F. In addition, the operation of HPRC at cruise conditions of around Mach 4.5 and at an altitude of 90, 000 ft lowers peak hot section temperatures to around 2800{degrees}F. An HPRC heat pipe was successfully fabricated and tested at Mach 5 conditions of heat flux, heat load, and temperature. 24 refs.

Martin, R.A.; Merrigan, M.A.; Elder, M.G.; Sena, J.T.; Keddy, E.S. (Los Alamos National Lab., NM (United States)); Silverstein, C.C. (CCS Associates, Bethel Park, PA (United States))

1992-01-01T23:59:59.000Z

317

Analytical and experimental studies of heat pipe radiation cooling of hypersonic propulsion systems  

SciTech Connect

Preliminary, research-oriented, analytical and experimental studies were completed to assess the feasibility of using high-temperature heat pipes to cool hypersonic engine components. This new approach involves using heat pipes to transport heat away from the combustor, nozzle, or inlet regions, and to reject it to the environment by thermal radiation from an external heat pipe nacelle. For propulsion systems using heat pipe radiation cooling (HPRC), it is possible to continue to use hydrocarbon fuels into the Mach 4 to Mach 6 speed range, thereby enhancing the economic attractiveness of commercial or military hypersonic flight. In the second-phase feasibility program recently completed, we found that heat loads produced by considering both convection and radiation heat transfer from the combustion gas can be handled with HPRC design modifications. The application of thermal insulation to ramburner and nozzle walls was also found to reduce the heat load by about one-half and to reduce peak HPRC system temperatures to below 2700{degrees}F. In addition, the operation of HPRC at cruise conditions of around Mach 4.5 and at an altitude of 90, 000 ft lowers peak hot section temperatures to around 2800{degrees}F. An HPRC heat pipe was successfully fabricated and tested at Mach 5 conditions of heat flux, heat load, and temperature. 24 refs.

Martin, R.A.; Merrigan, M.A.; Elder, M.G.; Sena, J.T.; Keddy, E.S. [Los Alamos National Lab., NM (United States); Silverstein, C.C. [CCS Associates, Bethel Park, PA (United States)

1992-06-01T23:59:59.000Z

318

Radiation environment simulations at the Tevatron, studies of the beam profile and measurement of the Bc meson mass  

Science Conference Proceedings (OSTI)

The description of a computer simulation of the CDF detector at Fermilab and the adjacent accelerator parts is detailed, with MARS calculations of the radiation background in various elements of the model due to the collision of beams and machine-related losses. Three components of beam halo formation are simulated for the determination of the principal source of radiation background in CDF due to beam losses. The effect of a collimator as a protection for the detector is studied. The simulation results are compared with data taken by a CDF group. Studies of a 150 GeV Tevatron proton beam are performed to investigate the transverse diffusion growth and distribution. A technique of collimator scan is used to scrape the beam under various experimental conditions, and computer programs are written for the beam reconstruction. An average beam halo growth speed is given and the potential of beam tail reconstruction using the collimator scan is evaluated. A particle physics analysis is conducted in order to detect the B{sub c} {yields} J/{psi}{pi} decay signal with the CDF Run II detector in 360 pb{sup -1} of data. The cut variables and an optimization method to determine their values are presented along with a criterion for the detection threshold of the signal. The mass of the B{sub c} meson is measured with an evaluation of the significance of the signal.

Nicolas, Ludovic Y.; /Glasgow U.

2005-09-01T23:59:59.000Z

319

Non-targeted effects of ionising radiation (NOTE) Â… a new European Integrated project, 2006-2010  

NLE Websites -- All DOE Office Websites (Extended Search)

targeted effects of ionising radiation (NOTE) - targeted effects of ionising radiation (NOTE) - a new European Integrated project, 2006-2010 Sisko Salomaa 1 , Eric G. Wright 2 , Guido Hildebrandt 3 , Munira Kadhim 4 , Mark P. Little 5 , Kevin M. Prise 6 , and Oleg V. Belyakov 1 1 Research and Environmental Surveillance, STUK - Radiation and Nuclear Safety Authority, Helsinki FI-00881, Finland 2 University of Dundee, Division of Pathology and Neuroscience, Molecular and Cellular Pathology Laboratories, Ninewells Hospital and Medical School, Dundee DD1 9SY, Scotland, UK 3 Department of Radiotherapy and Radiooncology, University of Leipzig, Leipzig 04103, Germany 4 MRC Radiation and Genome Stability Unit, Harwell, Didcot, Oxfordshire OX11 ORD, UK 5 Department of Epidemiology and Public Health, Imperial College Faculty of Medicine,

320

Low dose radiation effects of multipotent neural stem and progenitor cells  

NLE Websites -- All DOE Office Websites (Extended Search)

effects of multipotent neural stem and progenitor cells effects of multipotent neural stem and progenitor cells Charles L. Limoli, Department of Radiation Oncology, University of California, Irvine 92697-2695 Multipotent neural cells (both stem cells and their precursor cell progeny) retain their capacity to proliferate and differentiate throughout the mammalian lifespan. High numbers of these cells are located within the dentate subgranular zone (SGZ) of the hippocampus and the subventricular (SVZ) zone adjacent to the lateral ventricles, where they produce cells that can migrate away and differentiate into neurons (neurogenesis) and glia (gliogenesis). The realization that the brain contains such cells has sparked intense interest and speculation regarding their potential function. While significant data

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Aerosol Radiative Effects and Single-Scattering Properties in the Tropical Western Pacific  

NLE Websites -- All DOE Office Websites (Extended Search)

Effects and Single-Scattering Properties Effects and Single-Scattering Properties in the Tropical Western Pacific A. M. Vogelmann and P. J. Flatau Center for Atmospheric Sciences Scripps Institution of Oceanography University of California San Diego, California M. A. Miller, M. J. Bartholomew, and R. M. Reynolds Brookhaven National Laboratory Upton, New York P. J. Flatau University Corporation for Atmospheric Research Naval Research Laboratory Monterey, California K. M. Markowicz Institute of Geophysics University of Warsaw Warsaw, Poland Introduction The Atmospheric Radiation Measurement (ARM) Tropical Western Pacific (TWP) sites are downwind from Southeast Asia where biomass burning occurs and can advect over the tropical warm pool. Previous research (Vogelmann 2001, 2002, 2003) indicates that aerosol forcing was particularly large

322

A Prospective, Multicenter Study of Complementary/Alternative Medicine (CAM) Utilization During Definitive Radiation for Breast Cancer  

Science Conference Proceedings (OSTI)

Purpose: Although complementary and alternative medicine (CAM) utilization in breast cancer patients is reported to be high, there are few data on CAM practices in breast patients specifically during radiation. This prospective, multi-institutional study was conducted to define CAM utilization in breast cancer during definitive radiation. Materials/Methods: A validated CAM instrument with a self-skin assessment was administered to 360 Stage 0-III breast cancer patients from 5 centers during the last week of radiation. All data were analyzed to detect significant differences between users/nonusers. Results: CAM usage was reported in 54% of the study cohort (n=194/360). Of CAM users, 71% reported activity-based CAM (eg, Reiki, meditation), 26% topical CAM, and 45% oral CAM. Only 16% received advice/counseling from naturopathic/homeopathic/medical professionals before initiating CAM. CAM use significantly correlated with higher education level (P<.001), inversely correlated with concomitant hormone/radiation therapy use (P=.010), with a trend toward greater use in younger patients (P=.066). On multivariate analysis, level of education (OR: 6.821, 95% CI: 2.307-20.168, P<.001) and hormones/radiation therapy (OR: 0.573, 95% CI: 0.347-0.949, P=.031) independently predicted for CAM use. Significantly lower skin toxicity scores were reported in CAM users vs nonusers, respectively (mild: 34% vs 25%, severe: 17% vs 29%, P=.017). Conclusion: This is the first prospective study to assess CAM practices in breast patients during radiation, with definition of these practices as the first step for future investigation of CAM/radiation interactions. These results should alert radiation oncologists that a large percentage of breast cancer patients use CAM during radiation without disclosure or consideration for potential interactions, and should encourage increased awareness, communication, and documentation of CAM practices in patients undergoing radiation treatment for breast cancer.

Moran, Meena S., E-mail: meena.moran@yale.edu [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Department of Radiation Therapy, William W. Backus Hospital, Norwich, Connecticut (United States); Ma Shuangge [Department of Epidemiology and Public Health, Yale University, New Haven, Connecticut (United States)] [Department of Epidemiology and Public Health, Yale University, New Haven, Connecticut (United States); Jagsi, Reshma [University of Michigan, Department of Radiation Oncology, Ann Arbor, MI (United States)] [University of Michigan, Department of Radiation Oncology, Ann Arbor, MI (United States); Yang, Tzu-I Jonathan [Yale University School of Medicine, New Haven, Connecticut (United States)] [Yale University School of Medicine, New Haven, Connecticut (United States); Higgins, Susan A. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States) [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Department of Radiation Therapy, Shoreline Medical Center, Guilford, Connecticut (United States); Weidhaas, Joanne B. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States)] [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Wilson, Lynn D. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States) [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Department of Radiation Therapy, Lawrence and Memorial Hospital, New London, Connecticut (United States); Lloyd, Shane [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States)] [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Peschel, Richard [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States) [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Department of Radiation Therapy, Lawrence and Memorial Hospital, New London, Connecticut (United States); Gaudreau, Bryant [Department of Radiation Therapy, William W. Backus Hospital, Norwich, Connecticut (United States)] [Department of Radiation Therapy, William W. Backus Hospital, Norwich, Connecticut (United States); Rockwell, Sara [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States)] [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States)

2013-01-01T23:59:59.000Z

323

A research program on radiative, chemical, and dynamical feedback progresses influencing the carbon dioxide and trace gases climate effects: Annual progress report, September 1, 1986--July 15, 1989  

SciTech Connect

This report summarizes the up-to-date progress. The program includes two tasks: atmospheric radiation and climatic effects and their objective is to link quantitatively the radiation forcing changes and the climate responses caused by increasing greenhouse gases. Here, the objective and approach are described. We investigate the combined atmospheric radiation characteristics of the greenhouse gases (H/sub 2/O, CO/sub 2/, CH/sub 4/, N/sub 2/O, CFCs, and O/sub 3/), aerosols and clouds. Since the climatic effect of increasing atmospheric greenhouse gases is initiated by perturabtion to the longwave thermal radiation, it is critical to understand better the radiation characteristics of the greenhouse gases and their relationship to radiatively-important aerosols and clouds; the latter reflect solar radiation (a cooling of the surface) and provide a greenhouse effect (a warming to the surface). Therefore, aerosol and cloud particles are an integral part of the radiation field in the atmosphere. 9 refs.

1989-07-01T23:59:59.000Z

324

Alpha and gamma radiation effects on air-water systems at high gas/liquid ratios  

SciTech Connect

Radiolysis tests were conducted on air-water systems to examine the effects of radiation on liquid phase chemistry under high gas/liquid volume (G/L) ratios that are characteristic of an unsaturated nuclear waste repository setting. Test parameters included temperatures of 25, 90, and 200{degrees}C; gamma vs. alpha radiation; dose rates of {approximately}3500 and 50,000 rad/h; and G/L ratios of 10 and 100. Formate, oxalate, and total organic carbon contents increased during irradiation of the air-water systems in gamma and alpha tests at low-dose rate ({approximately}3500 rad/h). Increases in organic components were not observed for tests run at 200{degrees}C or high-dose rates (50,000 rad/h). In the tests where increases in organics occurred, the formate and oxalate were preferentially enriched in solutions that were rinsed from the test vessel walls. Nitrate (NO{sub 3}{sup {minus}}) is the dominant anion produced during the radiolysis reactions. Significant nitrite (NO{sub 2}{sup {minus}}) also occurs in some high-dose rate tests, with the reduced form of nitrogen possibly resulting from reactions with the test vessels. These results indicate that nitrogen acids are being produced and concentrated in the limited quantities of solution present in the tests. Nitrate + nitrite production varied inversely with temperature, with the lowest quantities being detected for the higher temperature tests. The G(NO{sub 3}{sup {minus}} + NO{sub 2}{sup {minus}}) values for the 25, 90, and 200{degrees}C experiments with gamma radiation are 3.2 {+-} 0.7, 1.3 {+-} 1.0, and 0.4 {+-} 0.3, respectively. Thus, the elevated temperatures expected early in the life of a repository may counteract pH decreases resulting from nitrogen acid production. Little variation was observed in G values as a function of dose rate or gas/liquid ratio.

Wronkiewicz, D.J.; Bates, J.K.

1993-08-01T23:59:59.000Z

325

Effects of the Mt. Pinatubo eruption on the radiative and chemical processes in the troposphere and stratosphere  

Science Conference Proceedings (OSTI)

The LLNL 2-D zonally averaged chemical-radiative transport model of the global atmosphere was used to study the effects of the June 15, 1991 eruption of the Mt. Pinatubo volcano on stratospheric processes. SAGE-11 time-dependent aerosol surface area density and optical extinction data were used as input into the model. By the winter solstice, 1991, a maximum change in column ozone was observed in the equatorial region of {minus}2% (with heterogeneous chemical reactions on sulfuric acid aerosols) and {minus}5.5% (including heterogeneous reactions plus radiative feedbacks). Maximum local ozone decreases of 12% were derived in the equatorial region, at 25 km, for winter solstice 1991. Column NO{sub 2} peaked ({minus}14%) at 30 S in October 1991. Local concentrations of NO{sub x}, Cl{sub x}, and HO{sub x}, in the lower stratosphere, were calculated to have changed between 30 S and 30 N by {minus}40%, +80%, and +60% respectively.

Kinnison, D.E.; Grant, K.E.; Connell, P.S.; Wuebbles, D.J.

1992-07-05T23:59:59.000Z

326

Insufficiency Fractures After Pelvic Radiation Therapy for Uterine Cervical Cancer: An Analysis of Subjects in a Prospective Multi-institutional Trial, and Cooperative Study of the Japan Radiation Oncology Group (JAROG) and Japanese Radiation Oncology Study Group (JROSG)  

Science Conference Proceedings (OSTI)

Purpose: To investigate pelvic insufficiency fractures (IF) after definitive pelvic radiation therapy for early-stage uterine cervical cancer, by analyzing subjects of a prospective, multi-institutional study. Materials and Methods: Between September 2004 and July 2007, 59 eligible patients were analyzed. The median age was 73 years (range, 37-84 years). The International Federation of Gynecologic Oncology and Obstetrics stages were Ib1 in 35, IIa in 12, and IIb in 12 patients. Patients were treated with the constant method, which consisted of whole-pelvic external-beam radiation therapy of 50 Gy/25 fractions and high-dose-rate intracavitary brachytherapy of 24 Gy/4 fractions without chemotherapy. After radiation therapy the patients were evaluated by both pelvic CT and pelvic MRI at 3, 6, 12, 18, and 24 months. Diagnosis of IF was made when the patients had both CT and MRI findings, neither recurrent tumor lesions nor traumatic histories. The CT findings of IF were defined as fracture lines or sclerotic linear changes in the bones, and MRI findings of IF were defined as signal intensity changes in the bones, both on T1- and T2-weighted images. Results: The median follow-up was 24 months. The 2-year pelvic IF cumulative occurrence rate was 36.9% (21 patients). Using Common Terminology Criteria for Adverse Events version 3.0, grade 1, 2, and 3 IF were seen in 12 (21%), 6 (10%), and 3 patients (5%), respectively. Sixteen patients had multiple fractures, so IF were identified at 44 sites. The pelvic IF were frequently seen at the sacroileal joints (32 sites, 72%). Nine patients complained of pain. All patients' pains were palliated by rest or non-narcotic analgesic drugs. Higher age (>70 years) and low body weight (<50 kg) were thought to be risk factors for pelvic IF (P=.007 and P=.013, Cox hazard test). Conclusions: Cervical cancer patients with higher age and low body weight may be at some risk for the development of pelvic IF after pelvic radiation therapy.

Tokumaru, Sunao, E-mail: tokumaru@cc.saga-u.ac.jp [Department of Heavy Particle Therapy and Radiation Oncology, Saga University, Saga (Japan)] [Department of Heavy Particle Therapy and Radiation Oncology, Saga University, Saga (Japan); Toita, Takafumi [Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Okinawa (Japan)] [Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Okinawa (Japan); Oguchi, Masahiko [Radiation Oncology Department, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo (Japan)] [Radiation Oncology Department, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo (Japan); Ohno, Tatsuya [Gunma University Heavy Ion Medical Center, Maebashi (Japan)] [Gunma University Heavy Ion Medical Center, Maebashi (Japan); Kato, Shingo [Department of Radiation Oncology, Saitama Medical University, International Medical Center, Saitama (Japan)] [Department of Radiation Oncology, Saitama Medical University, International Medical Center, Saitama (Japan); Niibe, Yuzuru [Department of Radiology, School of Medicine, Kitasato University, Sagamihara (Japan)] [Department of Radiology, School of Medicine, Kitasato University, Sagamihara (Japan); Kazumoto, Tomoko [Department of Radiology, Saitama Cancer Center, Saitama (Japan)] [Department of Radiology, Saitama Cancer Center, Saitama (Japan); Kodaira, Takeshi [Department of Radiation Oncology, Aichi Cancer Center, Nagoya (Japan)] [Department of Radiation Oncology, Aichi Cancer Center, Nagoya (Japan); Kataoka, Masaaki [Department of Radiology, National Shikoku Cancer Center, Matsuyama (Japan)] [Department of Radiology, National Shikoku Cancer Center, Matsuyama (Japan); Shikama, Naoto [Department of Radiation Oncology, Saitama Medical University, International Medical Center, Saitama (Japan)] [Department of Radiation Oncology, Saitama Medical University, International Medical Center, Saitama (Japan); Kenjo, Masahiro [Department of Radiation Oncology, Graduate School of Medical Science, Hiroshima University, Hiroshima (Japan)] [Department of Radiation Oncology, Graduate School of Medical Science, Hiroshima University, Hiroshima (Japan); Yamauchi, Chikako [Department of Radiation Oncology, Shiga Medical Center for Adults, Moriyama (Japan)] [Department of Radiation Oncology, Shiga Medical Center for Adults, Moriyama (Japan); Suzuki, Osamu [Department of Radiation Oncology, Osaka Medical Center for Cancer, Osaka (Japan)] [Department of Radiation Oncology, Osaka Medical Center for Cancer, Osaka (Japan); Sakurai, Hideyuki [Proton Medical Research Center and Tsukuba University, Tuskuba (Japan)] [Proton Medical Research Center and Tsukuba University, Tuskuba (Japan); Teshima, Teruki [Department of Medical Physics and Engineering, Graduate School of Medicine, Osaka University, Suita (Japan)] [Department of Medical Physics and Engineering, Graduate School of Medicine, Osaka University, Suita (Japan); Kagami, Yoshikazu [Department of Radiology, Showa University School of Medicine, Tokyo (Japan)] [Department of Radiology, Showa University School of Medicine, Tokyo (Japan); Nakano, Takashi [Department of Radiation Oncology, Gunma University, Graduate School of Medicine, Maebashi (Japan)] [Department of Radiation Oncology, Gunma University, Graduate School of Medicine, Maebashi (Japan); Hiraoka, Masahiro [Department of Radiation Oncology and Image-applied Therapy, Kyoto University, Graduate School of Medicine, Kyoto (Japan)] [Department of Radiation Oncology and Image-applied Therapy, Kyoto University, Graduate School of Medicine, Kyoto (Japan); and others

2012-10-01T23:59:59.000Z

327

Analysis of time-dependent radiation-induced conductivity in dielectrics and effect on cable SGEMP  

SciTech Connect

Analytic and numerical solutions are presented for a simple time-dependent solid-state band model of radiation-induced conductivity in polyethelene and Teflon. The analytic solution is found to provide insight to physical processes dominant in various intervals of time throughout the radiation pulse. The numerical solution provides a representation for the dose-dependent proportionality factor F(..gamma..), proposed by van Lint et al, used to calculate prompt conductivity from sigma/rho/ = F(..gamma..)..gamma... At high doses, F(..gamma..) is an order of magnitude smaller than at low doses. This decrease of F(..gamma..) is due to bimolecular recombination, an effect apparently not previously reported experimentally. The reduction in F(..gamma..) at high doses is shown to enhance the short circuit current for a cable SGEMP model of residual gaps by a factor of three. In addition, the dose-dependent behavior of F(..gamma..) can significantly alter the shape and time of occurrence of the peak of the waveform of this short circuit current compared to corresponding results for a dose-independent factor.

Shaeffer, D.L.; Siegel, J.M.

1982-12-01T23:59:59.000Z

328

Simulating 3-D Radiative Transfer Effects over the Sierra Nevada Mountains using WRF  

Science Conference Proceedings (OSTI)

A surface solar radiation parameterization based on deviations between 3-D and conventional plane-parallel radiative transfer models has been incorporated into the Weather Research and Forecasting (WRF) model to understand the solar insolation over mountain/snow areas and to investigate the impact of the spatial and temporal distribution and variation of surface solar fluxes on land-surface processes. Using the Sierra-Nevada in the western United States as a testbed, we show that mountain effect could produce up to ?50 to + 50Wm?2 deviations in the surface solar fluxes over the mountain areas, resulting in a temperature increase of up to 1 °C on the sunny side. Upward surface sensible and latent heat fluxes are modulated accordingly to compensate for the change in surface solar fluxes. Snow water equivalent and surface albedo both show decreases on the sunny side of the mountains, indicating more snowmelt and hence reduced snow albedo associated with more solar insolation due to mountain effect. Soil moisture increases on the sunny side of the mountains due to enhanced snowmelt, while decreases on the shaded side. Substantial differences are found in the morning hours from 8-10 a.m. and in the afternoon around 3-5 p.m., while differences around noon and in the early morning and late afternoon are comparatively smaller. Variation in the surface energy balance can also affect atmospheric processes, such as cloud fields, through the modulation of vertical thermal structure. Negative changes of up to ?40 gm?2 are found in the cloud water path, associated with reductions in the surface insolation over the cloud region. The day-averaged deviations in the surface solar flux are positive over the mountain areas and negative in the valleys, with a range between ?12~12Wm?2. Changes in sensible and latent heat fluxes and surface skin temperature follow the solar insolation pattern. Differences in the domain-averaged diurnal variation over the Sierras show that the mountain area receives more solar insolation during early morning and late afternoon, resulting in enhanced upward sensible heat and latent heat fluxes from the surface and a corresponding increase in surface skin temperature. During the middle of the day, however, the surface insolation and heat fluxes show negative changes, indicating a cooling effect. Hence overall, the diurnal variations of surface temperature and surface fluxes in the Sierra-Nevada are reduced through the interactions of radiative transfer and mountains. The hourly differences of the surface solar insolation in higher elevated regions, however, show smaller magnitude in negative changes during the middle of the day and possibly more solar fluxes received during the whole day.

Gu, Yu; Liou, K. N.; Lee, W- L.; Leung, Lai-Yung R.

2012-10-30T23:59:59.000Z

329

Irradiators for measuring the biological effects of low dose-rate ionizing radiation fields  

E-Print Network (OSTI)

Biological response to ionizing radiation differs with radiation field. Particle type, energy spectrum, and dose-rate all affect biological response per unit dose. This thesis describes methods of spectral analysis, ...

Davidson, Matthew Allen

2011-01-01T23:59:59.000Z

330

The Effect of Cloud Sides on Reflected Solar Radiation as Deduced from Satellite Observations  

Science Conference Proceedings (OSTI)

We report the observation of a feature that is characteristic of the reflection of solar radiation from absorbing, finite clouds. When absorption takes place, more radiation can be reflected by broken cloud fields than by extensive unbroken cloud ...

James A. Coakley Jr.; Roger Davies

1986-05-01T23:59:59.000Z

331

Lung cancer mortality between 1950 and 1987 after exposure to fractionated moderate-dose-rate ionizing radiation in the Canadian fluoroscopy cohort study and a comparison with lung cancer mortality in the atomic bomb survivors study  

Science Conference Proceedings (OSTI)

Current lung cancer risk estimates after exposure to low-linear energy transfer radiation such as X rays are based on studies of people exposed to such radiation at high dose rates, for example the atomic bomb survivors. Radiobiology and animal experiments suggest that risks from exposure at low to moderate dose rates, for example medical diagnostic procedures, may be overestimated by such risk models, but data for humans to examine this issue are limited. In this paper we report on lung cancer mortality between 1950 and 1987 in a cohort of 64,172 Canadian tuberculosis patients, of whom 39% were exposed to highly fractionated multiple chest fluoroscopies leading to a mean lung radiation dose of 1.02 Sv received at moderate dose rates. These data have been used to estimate the excess relative risk per sievert of lung cancer mortality, and this is compared directly to estimates derived from 75,991 atomic bomb survivors. Based on 1,178 lung cancer deaths in the fluoroscopy study, there was no evidence of any positive association between risk and dose, with the relative risk at 1 Sv being 1.00 (95% confidence interval 0.94, 1.07), which contrasts with that based on the atomic bomb survivors, 1.60 (1.27, 1.99). The difference in effect between the two studies almost certainly did not arise by chance (P = 0.0001). This study provides strong support from data for humans for a substantial fractionation/dose-rate effect for low-linear energy transfer radiation and lung cancer risk. This implies that lung cancer risk from exposures to such radiation at present-day dose rates is likely to be lower than would be predicted by current radiation risk models based on studies of high-dose-rate exposures. 25 refs., 8 tabs.

Howe, G.R. [Univ. of Toronto, Ontario (Canada)

1995-06-01T23:59:59.000Z

332

Potential Aerosol Indirect Effects on Atmospheric Circulation and Radiative Forcing through Deep Convection  

Science Conference Proceedings (OSTI)

Aerosol indirect effects, i.e., the interactions of aerosols with clouds by serving as cloud condensation nuclei (CCN) or ice nuclei (IN), constitute the largest uncertainty in climate forcing and projection. Previous IPCC reported aerosol indirect forcing is negative, which does not account for aerosol-convective cloud interactions because the complex processes involved are poorly understood and represented in climate models. Here we report that aerosol indirect effect on deep convective cloud systems can lead to enhanced regional convergence and a strong top-of atmosphere (TOA) warming. Aerosol invigoration effect on convection can result in a strong radiative warming in the atmosphere (+5.6 W m-2) due to strong night-time warming, a lofted latent heating, and a reduced diurnal temperature difference, all of which could remarkably impact regional circulation and modify weather systems. We further elucidated how aerosols change convective intensity, diabatic heating, and regional circulation under different environmental conditions and concluded that wind shear and cloud base temperature play key roles in determining the significance of aerosol invigoration effect for convective systems.

Fan, Jiwen; Rosenfeld, Daniel; Ding, Yanni; Leung, Lai-Yung R.; Li, Zhanqing

2012-05-10T23:59:59.000Z

333

EFFECT OF SURFACE PREPARATION TECHNIQUE ON THE RADIATION DETECTOR PERFORMANCEOF CDZNTE  

Science Conference Proceedings (OSTI)

Synthetic CdZnTe (CZT) semiconducting crystals are highly suitable for the room temperature-based detection of gamma radiation. The surface preparation of Au contacts on surfaces of CZT detectors is typically conducted after (1) polishing to remove artifacts from crystal sectioning and (2) chemical etching, which removes residual mechanical surface damage however etching results in a Te rich surface layer that is prone to oxidize. Our studies show that CZT surfaces that are only polished (as opposed to polished and etched) can be contacted with Au and will yield lower surface currents. Due to their decreased dark currents, these as-polished surfaces can be used in the fabrication of gamma detectors exhibiting a higher performance than polished and etched surfaces with relatively less peak tailing and greater energy resolution. CdZnTe or ''CZT'' crystals are attractive to use in homeland security applications because they detect radiation at room temperature and do not require low temperature cooling as with silicon- and germanium-based detectors. Relative to germanium and silicon detectors, CZT is composed of higher Z elements and has a higher density, which gives it greater ''stopping power'' for gamma rays making a more efficient detector. Single crystal CZT materials with high bulk resistivity ({rho}>10{sup 10} {Omega} x cm) and good mobility-lifetime products are also required for gamma-ray spectrometric applications. However, several factors affect the detector performance of CZT are inherent to the as grown crystal material such as the presence of secondary phases, point defects and the presence of impurities (as described in a literature review by R. James and researchers). These and other factors can limit radiation detector performance such as low resistivity, which causes a large electronic noise and the presence of traps and other heterogeneities, which result in peak tailing and poor energy resolution.

Duff, M

2007-05-23T23:59:59.000Z

334

Radiation Therapy After Breast-Conserving Surgery: Does Hospital Surgical Volume Matter? A Population-Based Study in Taiwan  

SciTech Connect

Purpose: To examine the association between hospital surgical volume and the use of radiation therapy (RT) after breast-conserving surgery (BCS) in Taiwan. Methods and Materials: We used claims data from the National Health Insurance program in Taiwan (1997-2005) in this retrospective population-based study. We identified patients with breast cancer, receipt of BCS, use of radiation, and the factors that could potentially associated with the use of RT from enrollment records, and the ICD-9 and billing codes in claims. We conducted logistic regression to examine factors associated with RT use after BCS, and performed subgroup analyses to examine whether the association differs by medical center status or hospital volumes. Results: Among 5,094 patients with newly diagnosed invasive breast cancer who underwent BCS, the rate of RT was significantly lower in low-volume hospitals (74% vs. 82%, p < 0.01). Patients treated in low-volume hospitals were less likely to receive RT after BCS (odds ratio = 0.72, 95% confidence interval = 0.62-0.83). In addition, patients treated after the implementation of the voluntary pay-for-performance policy in 2001 were more likely to receive RT (odds ratio = 1.23; 95% confidence interval = 1.05-1.45). Subgroup analyses indicated that the high-volume effect was limited to hospitals accredited as non-medical centers, and that the effect of the pay-for-performance policy was most pronounced among low-volume hospitals. Conclusions: Using population-based data from Taiwan, our study concluded that hospital surgical volume and pay-for-performance policy are positively associated with RT use after BCS.

Chien, Chun-Ru [Section of Health Services Research, Department of Biostatistics, Division of Quantitative Sciences, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Department of Radiation Oncology, China Medical University Hospital, and School of Medicine, China Medical University, Taichung, Taiwan (China); Pan, I-Wen [Section of Health Services Research, Department of Biostatistics, Division of Quantitative Sciences, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Tsai, Yi-Wen [Center of Health Policy Research and Development, National Health Research Institutes, Miaoli County, Taiwan (China); Institute of Health and Welfare Policy, National Yang-Ming University Hospital, Taipei, Taiwan (China); Tsai, Teressa [Center of Health Policy Research and Development, National Health Research Institutes, Miaoli County, Taiwan (China); Liang, Ji-An [Department of Radiation Oncology, China Medical University Hospital, and School of Medicine, China Medical University, Taichung, Taiwan (China); Buchholz, Thomas A. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Shih, Ya-Chen Tina, E-mail: yashih@mdanderson.org [Section of Health Services Research, Department of Biostatistics, Division of Quantitative Sciences, University of Texas MD Anderson Cancer Center, Houston, TX (United States)

2012-01-01T23:59:59.000Z

335

A Study of the Incoming Longwave Atmospheric Radiation from a Clear Sky  

Science Conference Proceedings (OSTI)

A band model for atmospheric absorption is used to calculate the incoming longwave atmospheric radiative flux for some typical clear sky conditions. The sky radiation is also measured using a specially-designed calorimetric apparatus over a wide ...

J. W. Ramsey; H. D. Chiang; R. J. Goldstein

1982-04-01T23:59:59.000Z

336

IR Radiation from Trees to a Ski Run: A Case Study  

Science Conference Proceedings (OSTI)

Accurately calculating the surface radiation budget of a groomed ski run is crucial when determining snow surface temperature and other snow-related variables, knowledge of which is important for ski racing. Downwelling longwave radiation can ...

Rosie Howard; Roland Stull

2013-07-01T23:59:59.000Z

337

Observational and Theoretical Studies of Solar Radiation in Arctic Stratus Clouds  

Science Conference Proceedings (OSTI)

A series of clouds-radiation experiments was carried out in June 1980 in Arctic stratus clouds occurring over the Beaufort Sea using the NCAR Electra aircraft. This paper is an analysis of the hemispheric radiation fields obtained with Eppley ...

G. F. Herman; J. A. Curry

1984-01-01T23:59:59.000Z

338

"Radiative Closure Studies for Clear Skies During the ARM 2003 Aerosol Intensive Observation Period"  

SciTech Connect

The Department of Energy's Atmospheric Radiation Measurement (ARM) program sponsored a large intensive observation period (IOP) to study aerosol during the month of May 2003 around the Southern Great Plains (SGP) Climate Research Facility (CRF) in north central Oklahoma. Redundant measurements of aerosol optical properties were made using different techniques at the surface as well as in vertical profile with sensors aboard two aircraft. One of the principal motivations for this experiment was to resolve the disagreement between models and measurements of diffuse horizontal broadband shortwave irradiance at the surface, especially for modest aerosol loading. This paper focuses on using the redundant aerosol and radiation measurements during this IOP to compare direct beam and diffuse horizontal broadband shortwave irradiance measurements and models at the surface for a wide range of aerosol cases that occurred during 30 clear-sky periods on 13 days of May 2003. Models and measurements are compared over a large range of solar-zenith angles. Six different models are used to assess the relative agreement among them and the measurements. Better agreement than previously achieved appears to be the result of better specification of input parameters and better measurements of irradiances than in prior studies. Biases between modeled and measured direct irradiances are less than 1%, and biases between modeled and measured diffuse irradiances are less than 2%.

J. J. Michalsky, G. P. Anderson, J. Barnard, J. Delamere, C. Gueymard, S. Kato, P. Kiedron, A. McComiskey, and P. Ricchiazzi

2006-04-01T23:59:59.000Z

339

Support of Activities of the NAS in Relation to the Radiation Effects Research Foundation  

Science Conference Proceedings (OSTI)

The National Academies (NA) provides support for the activities related to the long-term follow up of the health of the survivors of the atomic bombings of Hiroshima and Nagasaki being conducted by the Radiation Effects Research Foundation (RERF) laboratories in Hiroshima and Nagasaki, Japan. The NA serves as scientific and administrative liaison between the U.S. Department of Energy (DOE) and RERF, and performs tasks in the areas of scientific oversight, information/public interface, fiscal oversight, and personnel management. The project includes recruitment and support of approximately 10 NA employees who work at RERF in Japan. Specific activities are performed consistent with the cooperative agreement’s Statement of Work between DOE and NA and consistent with an Annual Work Plan developed by DOE and NA.

Douple, Evan B.

2006-05-31T23:59:59.000Z

340

Spreader-Bar Radiation Detection System Enhancements: A Modeling and Simulation Study  

SciTech Connect

This report provides the modeling and simulation results of the investigation of enhanced spreader bar radiation detection systems.

Ely, James H.; Ashbaker, Eric D.; Batdorf, Michael T.; Baciak, James E.; Hensley, Walter K.; Jarman, Kenneth D.; Robinson, Sean M.; Sandness, Gerald A.; Schweppe, John E.

2012-11-13T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

World Wide Web Access to Radiation Datasets for Environmental and Climate Change Studies  

Science Conference Proceedings (OSTI)

Five years of scanner data from the Earth Radiation Budget Experiment (ERBE), eight years of surface radiation budget (SRB) data, and one year of scanner radiation budget data from the French–Russian–German experiment, ScaRaB, will be available ...

T. Dale Bess; Ann B. Carlson; Calvin Mackey; Fredrick M. Denn; Anne Wilber; Nancy Ritchey

2000-11-01T23:59:59.000Z

342

Neutron Radiation Embrittlement and Microstructural Characterization of Ferritic Steels: Joint EPRI-CRIEPI RPV Embrittlement Studies  

Science Conference Proceedings (OSTI)

The identification of mechanisms by which neutron radiation embrittlement occurs in reactor pressure vessel (RPV) ferritic material may permit the design of alloys in which the radiation-induced degradation in mechanical properties is minimized or eliminated. This report documents the microstructural characterization of several RPV steels that will be used to develop predictive models for radiation embrittlement.

1995-01-21T23:59:59.000Z

343

Conduction Effect of Thermal Radiation in a Metal Shield Pipe in a Cryostat for a Cryogenic Interferometric Gravitational Wave Detector  

E-Print Network (OSTI)

A large heat load caused by thermal radiation through a metal shield pipe was observed in a cooling test of a cryostat for a prototype of a cryogenic interferometric gravitational wave detector. The heat load was approximately 1000 times larger than the value calculated by the Stefan-Boltzmann law. We studied this phenomenon by simulation and experiment and found that it was caused by the conduction of thermal radiation in a metal shield pipe.

Takayuki Tomaru; Masao Tokunari; Kazuaki Kuroda; Takashi Uchiyama; Akira Okutomi; Masatake Ohashi; Hiroyuki Kirihara; Nobuhiro Kimura; Yoshio Saito; Nobuaki Sato; Takakazu Shintomi; Toshikazu Suzuki; Tomiyoshi Haruyama; Shinji Miyoki; Kazuhiro Yamamoto; Akira Yamamoto

2007-11-06T23:59:59.000Z

344

Cellular and molecular research to reduce uncertainties in estimates of health effects from low-level radiation  

Science Conference Proceedings (OSTI)

A study was undertaken by five radiation scientists to examine the feasibility of reducing the uncertainties in the estimation of risk due to protracted low doses of ionizing radiation. In addressing the question of feasibility, a review was made by the study group: of the cellular, molecular, and mammalian radiation data that are available; of the way in which altered oncogene properties could be involved in the loss of growth control that culminates in tumorigenesis; and of the progress that had been made in the genetic characterizations of several human and animal neoplasms. On the basis of this analysis, the study group concluded that, at the present time, it is feasible to mount a program of radiation research directed at the mechanism(s) of radiation-induced cancer with special reference to risk of neoplasia due to protracted, low doses of sparsely ionizing radiation. To implement a program of research, a review was made of the methods, techniques, and instruments that would be needed. This review was followed by a survey of the laboratories and institutions where scientific personnel and facilities are known to be available. A research agenda of the principal and broad objectives of the program is also discussed. 489 refs., 21 figs., 14 tabs.

Elkind, M.M.; Bedford, J.; Benjamin, S.A.; Waldren, C.A. (Colorado State Univ., Fort Collins, CO (USA)); Gotchy, R.L. (Science Applications International Corp., McLean, VA (USA))

1990-10-01T23:59:59.000Z

345

A review of ground-based heavy-ion radiobiology relevant to space radiation risk assessment: Part II. Cardiovascular and immunological effects  

E-Print Network (OSTI)

al. , Late effects of the chernobyl radiation accident on TMortality among the chernobyl emergency workers: estimationcerebrovascular disease in chernobyl emergency workers,

Blakely, Eleanor A.

2008-01-01T23:59:59.000Z

346

Head-and-Neck Target Delineation Among Radiation Oncology Residents After a Teaching Intervention: A Prospective, Blinded Pilot Study  

Science Conference Proceedings (OSTI)

Purpose: We conducted this study to determine the feasibility of incorporating a teaching intervention on target delineation into the educational curriculum of a radiation oncology residency program and to assess the short-term effects on resident skills. Methods and Materials: The study schema consisted of a baseline evaluation, the teaching intervention, and a follow-up evaluation. At the baseline evaluation, the participants contoured three clinical tumor volumes (CTVs) (70 Gy, 59.4 Gy, and 54 Gy) on six contrast-enhanced axial computed tomography images of a de-identified patient with Stage T2N2bM0 squamous cell carcinoma of the right base of the tongue. The participants attended a series of head-and-neck oncology and anatomy seminars. The teaching intervention consisted of a didactic lecture and an interactive hands-on practical session designed to improve the knowledge and skills for target delineation in the head and neck. At the follow-up evaluation, the residents again contoured the CTVs. Results: Of the 14 eligible residents, 11 (79%) actually participated in the study. For all participants, but especially for those who had not had previous experience with head-and-neck target delineation, the teaching intervention was associated with improvement in the delineation of the node-negative neck (CTV 54 Gy contour). Regardless of clinical experience, participants had difficulty determining what should be included in the CTV 59.4 Gy contour to ensure adequate coverage of potential microscopic disease. Conclusion: Incorporating a teaching intervention into the education curriculum of a radiation oncology residency program is feasible and was associated with short-term improvements in target delineation skills. Subsequent interventions will require content refinement, additional validation, longer term follow-up, and multi-institutional collaboration.

Bekelman, Justin E. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)], E-mail: bekelmaj@mskcc.org; Wolden, Suzanne; Lee, Nancy [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

2009-02-01T23:59:59.000Z

347

Phototoxic effect of conjugates of plasmon-resonance nanoparticles with indocyanine green dye on Staphylococcus aureus induced by IR laser radiation  

Science Conference Proceedings (OSTI)

The effect of IR laser radiation ({lambda} = 805 - 808 nm) on the bacteria of the strain Staphylococcus aureus 209 P, incubated in indocyanine green solutions, is studied, as well as that of colloid gold nanoshells, nanocages and their conjugates with indocyanine green. It is found that the S. aureus 209 P cells are equally subjected to the IR laser radiation ({lambda} = 805 nm) after preliminary sensitisation with indocyanine green and gold nanoparticles separately and with conjugates of nanoparticles and indocyanine green. The enhancement of photodynamic and photothermal effects by 5 % is observed after 30 min of laser illumination ({lambda} = 808 nm) of bacteria, treated with conjugates of indocyanine green and nanocages. (optical technologies in biophysics and medicine)

Tuchina, E S; Tuchin, Valerii V; Khlebtsov, B N; Khlebtsov, Nikolai G

2011-04-30T23:59:59.000Z

348

Assessment of the Effective Dose Equivalent for External Photon Radiation: Volume 2: Calculational Techniques for Estimating Externa l Effective Dose Equivalent from Dosimeter Readings  

Science Conference Proceedings (OSTI)

Recent revisions to the radiation protection standards contained in Title 10 Part 20 of the Code of Federal Regulations require nuclear power plants to assess a worker's "effective dose equivalent" (EDE). This report explains the concept of effective dose equivalent and describes research to improve the dosimetric methods presently used for assessing EDE.

1995-09-28T23:59:59.000Z

349

Isotope effect in the photochemical decomposition of CO{sub 2} (ice) by Lyman-{alpha} radiation  

SciTech Connect

The photochemical decomposition of CO{sub 2}(ice) at 75 K by Lyman-{alpha} radiation (10.2 eV) has been studied using transmission infrared spectroscopy. An isotope effect in the decomposition of the CO{sub 2} molecule in the ice has been discovered, favoring {sup 12}CO{sub 2} photodecomposition over {sup 13}CO{sub 2} by about 10%. The effect is caused by electronic energy transfer from the excited CO{sub 2} molecule to the ice matrix, which favors quenching of the heavier electronically-excited {sup 13}CO{sub 2} molecule over {sup 12}CO{sub 2}. The effect is similar to the Menzel-Gomer-Redhead isotope effect in desorption from adsorbed molecules on surfaces when electronically excited. An enhancement of the rate of formation of lattice-trapped CO and CO{sub 3} species is observed for the photolysis of the {sup 12}CO{sub 2} molecule compared to the {sup 13}CO{sub 2} molecule in the ice. Only 0.5% of the primary photoexcitation results in O-CO bond dissociation to produce trapped-CO and trapped-CO{sub 3} product molecules and the majority of the electronically-excited CO{sub 2} molecules return to the ground state. Here either vibrational relaxation occurs (majority process) or desorption of CO{sub 2} occurs (minority process) from highly vibrationally-excited CO{sub 2} molecules in the ice. The observation of the {sup 12}C/{sup 13}C isotope effect in the Lyman-{alpha} induced photodecomposition of CO{sub 2} (ice) suggests that over astronomical time scales the isotope enrichment effect may distort historical information derived from isotope ratios in space wherever photochemistry can occur.

Yuan Chunqing; Yates, John T. Jr. [Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904 (United States)

2013-04-21T23:59:59.000Z

350

Low Dose Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Ancient Salt Beds Ancient Salt Beds Repository Science Renewable Energy The WIPP Underground may be ideal to study effects of Very Low Dose Rates on Biological Systems Low Background Radiation Experiment We're all bathing in it. It's in the food we eat, the water we drink, the soil we tread and even the air we breathe. It's background radiation, it's everywhere and we can't get away from it. But what would happen if you somehow "pulled the plug" on natural background radiation? Would organisms suffer or thrive if they grew up without their constant exposure to background radiation? That's what a consortium of scientists conducting an experiment at the Waste Isolation Pilot Plant aim to find out. Despite being an underground repository for transuranic radioactive waste,

351

Using decision analysis to determine the cost-effectiveness of intensity-modulated radiation therapy in the treatment of intermediate risk prostate cancer  

SciTech Connect

Background: The specific aim of this study is to evaluate the cost-effectiveness of intensity-modulated radiation therapy (IMRT) compared with three-dimensional conformal radiation therapy (3D-CRT) in the treatment of a 70-year-old with intermediate-risk prostate cancer. Methods: A Markov model was designed with the following states; posttreatment, hormone therapy, chemotherapy, and death. Transition probabilities from one state to another were calculated from rates derived from the literature for IMRT and 3D-CRT. Utility values for each health state were obtained from preliminary studies of preferences conducted at Fox Chase Cancer Center. The analysis took a payer's perspective. Expected mean costs, cost-effectiveness scatterplots, and cost acceptability curves were calculated with commercially available software. Results: The expected mean cost of patients undergoing IMRT was $47,931 with a survival of 6.27 quality-adjusted life years (QALYs). The expected mean cost of patients having 3D-CRT was $21,865 with a survival of 5.62 QALYs. The incremental cost-effectiveness comparing IMRT with CRT was $40,101/QALYs. Cost-effectiveness acceptability curve analysis revealed a 55.1% probability of IMRT being cost-effective at a $50,000/QALY willingness to pay. Conclusion: Intensity-modulated radiation therapy was found to be cost-effective, however, at the upper limits of acceptability. The results, however, are dependent on the assumptions of improved biochemical disease-free survival with fewer patients undergoing subsequent salvage therapy and improved quality of life after the treatment. In the absence of prospective randomized trials, decision analysis can help inform physicians and health policy experts on the cost-effectiveness of emerging technologies.

Konski, Andre [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)]. E-mail: andre.konski@fccc.edu; Watkins-Bruner, Deborah [Department of Population Sciences, Fox Chase Cancer Center, Philadelphia, PA (United States); Feigenberg, Steven [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Hanlon, Alexandra [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Kulkarni, Sachin M.S. [Department of Population Sciences, Fox Chase Cancer Center, Philadelphia, PA (United States); Beck, J. Robert [Department of Information and Science Technologies, Fox Chase Cancer Center, Philadelphia, PA (United States); Horwitz, Eric M. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Pollack, Alan [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)

2006-10-01T23:59:59.000Z

352

Equatorial Inertial Instability: Effects of Vertical Finite Differencing and Radiative Transfer  

Science Conference Proceedings (OSTI)

The effect of vertical differencing on equatorial inertial instability is studied and explicit results obtained for growth rates as a function of the vertical resolution. It is found that for a basic state independent of height, the form of the ...

P. D. Clark; P. H. Haynes

1994-07-01T23:59:59.000Z

353

Study of the secondary neutral radiation in proton therapy: Toward an indirect in vivo dosimetry  

Science Conference Proceedings (OSTI)

Purpose: Secondary particles produced in the collision of protons with beam modifiers are of concern in proton therapy. Nevertheless, secondary radiation can provide information on the dosimetric parameters through its dependency on the modulating accessories (range shifter and range modulating wheel). Relatively little data have been reported in the literature for low-energy proton beams. The present study aims at characterizing the neutron and photon secondary radiation at the low-energy proton therapy facility of the Centre Antoine Lacassagne (CAL), and studying their correlation to the dosimetric parameters to explore possible practical uses of secondary radiation in the treatment quality for proton therapy. Methods: The Monte Carlo code MCNPX was used to simulate the proton therapy facility at CAL. Neutron and photon fluence, {Phi}, and ambient dose equivalent per proton dose, H*(10)/D, were determined across the horizontal main plane spanning the whole treatment room. H*(10)/D was also calculated at two positions of the treatment room where dosimetric measurements were performed for validation of the Monte Carlo calculations. Calculations and measurements were extended to 100 clinical spread-out Bragg Peaks (SOBPs) covering the whole range of therapeutic dose rates (D/MU) employed at CAL. In addition, the values of D and MU were also calculated for each SOBP and the results analyzed to study the relationship between secondary radiation and dosimetric parameters. Results: The largest production of the secondary particles takes place at the modulating devices and the brass collimators located along the optical bench. Along the beam line and off the beam axis to 2.5 m away, H*(10)/D values ranged from 5.4 {mu}Sv/Gy to 5.3 mSv/Gy for neutrons, and were 1 order of magnitude lower for photons. H*(10)/D varied greatly with the distance and angle to the beam axis. A variation of a factor of 5 was found for the different range of modulations (SOBPs). The ratios between calculations and measurements were 2.3 and 0.5 for neutrons and photons, respectively, and remained constant for all the range of SOBPs studied, which provided validation for the Monte Carlo calculations. H*(10)/D values were found to correlate to the proton dose rate D/MU with a power fit, both for neutrons and photons. This result was exploited to implement a system to obtain D/MU values from the measurement of the integrated photon ambient dose equivalent H*(10) during treatment, which provides a method to control the dosimetric parameters D/MU and D. Conclusions: The treatment room at CAL is moderately polluted by secondary particles. The constant ratio between measurements and calculations for all SOBPs showed that simulations correctly predict the dosimetric parameters and the dependence of the production of secondary particles on the modulation. The correlation between H*(10)/D and D/MU is a useful tool for quality control and is currently used at CAL. This system works as an indirect in vivo dosimetry method, which is so far not feasible in proton therapy. This tool requires very simple instrumentation and can be implemented from the measurement of either photons or neutrons.

Carnicer, A.; Letellier, V.; Rucka, G.; Angellier, G.; Sauerwein, W.; Herault, J. [Centre Antoine Lacassagne, Cyclotron Biomedical, 227 Avenue de la Lanterne, 06200 Nice (France); Institut Curie, Centre de Protontherapie, Campus Universitaire d'Orsay, Batiment 101, 91898 Orsay Cedex (France); Hopital de la Croix Rouge, Centre de radiotherapie St Louis, Rue Andre Blondel, 83100 Toulon (France); Centre Antoine Lacassagne, Cyclotron Biomedical, 227 Avenue de la Lanterne, 06200 Nice (France); Universitaet Duisburg-Essen, Universitaetsklinikum Essen, Strahlenklinik, 45122 Essen (Germany); Centre Antoine Lacassagne, Cyclotron Biomedical, 227 Avenue de la Lanterne, 06200 Nice (France)

2012-12-15T23:59:59.000Z

354

Thermal reactions of disilane on Si(100) studied by synchrotron-radiation photoemission  

SciTech Connect

H-terminated Si(100) surfaces were formed by saturation exposure of Si(100) to disilane at room temperature. Annealing these surfaces to progressively higher temperatures resulted in hydrogen desorption. This process, of basic importance to the growth of Si by atomic layer epitaxy using disilane, was studied by synchrotron-radiation photoemission. The Si 2[ital p] core-level line shape, the position of the Fermi level within the band gap, the work function, and the ionization potential were measured as a function of annealing temperature. These results revealed two steps in the thermal reaction preceding the recovery of the clean surface. The dihydride radicals on the surface are converted to monohydride radicals at 500--610 K, and the monohydride radicals decompose at 700--800 K.

Lin, D.; Miller, T.; Chiang, T. (Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080 (United States)); Tsu, R.; Greene, J.E. (Department of Materials Science and Engineering, Coordinated Science Laboratory, and Materials Research Laboratory, University of Illinois at Urbana-Champaign, 1304 West Green Street, Urbana, Illinois 61801-3080 (United States))

1993-10-15T23:59:59.000Z

355

The Effect of Changes in Cloud Amount on the Net Radiation at the Top of the Atmosphere  

Science Conference Proceedings (OSTI)

Due to the opposing albedo and greenhouse effects of clouds, the possibility exists that the net radiation at the top of the earth-atmosphere system is, in the mean, insensitive to changes in cloud amount. If so, this would have important ...

George Ohring; Philip Clapp

1980-02-01T23:59:59.000Z

356

Effect of Low Dose Radiation on Antioxidant Levels in Rat Brain  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Radiation on Antioxidant Levels in Rat Brain Mohan Doss Fox Chase Cancer Center Abstract Background: Parkinsons disease (PD) is characterized by progressive...

357

Separating Radiation and Thermal Effects on Lateral PNP Bipolar Junction Transistors Operating in the Space Environment.  

E-Print Network (OSTI)

??Radiation-induced gain degradation in bipolar devices is considered to be the primary threat to linear bipolar circuits operating in the space environment. The damage is… (more)

Campola, Michael Joseph

2011-01-01T23:59:59.000Z

358

Health Risks Associated with Low Doses of Radiation  

Science Conference Proceedings (OSTI)

Despite a wealth of information, there remains uncertainty concerning human radiation effects at low dose levels. This report provides background information and a literature review of research on the potential health hazards associated with exposure to low-level ionizing radiation. Topics include radiation characteristics, protection standards, epidemiologic data and risk models, the nature of human health exposure-related effects, important radiation health studies to date, and the scientific method fo...

1994-09-17T23:59:59.000Z

359

Effects of High Dietary Iron and Gamma Radiation on Oxidative Stress and Bone  

E-Print Network (OSTI)

Astronauts in space flight missions are exposed to increased iron (Fe) stores and galactic cosmic radiation, both of which independently induce oxidative stress. Oxidative stress can result in protein, lipid, and DNA oxidation. Recent evidence has linked oxidative stress to bone loss with aging and estrogen deficiency. Whether the increased iron stores and radiation that astronauts face are exacerbating their extreme bone loss while in space is unclear. We hypothesized that elevated iron levels (induced by feeding a high iron diet) and gamma radiation exposure would independently increase markers of oxidative stress and markers of oxidative damage and result in loss of bone mass, with the combined treatment having additive or synergistic effects. Male Sprague-Dawley rats (15-weeks old, n=32) were randomized to receive an adequate (45 mg Fe/kg diet) or high (650 mg Fe/kg diet) Fe diet for 4 weeks and either 3 Gy (8 fractions, 0.375 Gy each) of 137Cs radiation (?RAD) or sham exposure every other day over 16 days starting on day 14. Serum Fe and catalase and liver Fe and glutathione peroxidase (GPX) were assessed by standard techniques. Immunostaining for 8-hydroxy-2-deoxyguanosine (8-OHdG, marker of DNA adducts) quantified the number of cells with oxidative damage in cortical bone. Bone histomorphometry assessed bone cell activity and cancellous bone microarchitecture in the metaphyseal region. Ex vivo pQCT quantified volumetric bone mineral density (vBMD); bone mechanical strength was assessed by 3-pt bending at the midshaft tibia and compression of the femoral neck. High Fe diet increased liver Fe and decreased volume per total volume (BV/TV). ?RAD decreased osteoid surface per bone surface (OS/BS) and osteocyte density. The combined treatment increased serum catalase, liver GPX, and serum iron and decreased cancellous vBMD and trabecular number (Tb.N). High Fe diet and ?RAD independently increased number of osteocytes stained positive for 8-OHdG, with the combined treatment exhibiting twice as many osteocytes positively stained compared to the control. Higher serum Fe levels were associated with higher oxidative damage (r =0.38) and lower proximal tibial cancellous vBMD (r =–0.38). Higher serum catalase levels were associated with higher oxidative damage (r =0.48), lower BV/TV (r =–0.40) and lower cancellous vBMD (r =–0.39). High dietary iron and fractionated 137Cs ?RAD leads to a moderate elevation in iron stores and results in oxidative damage in bone and are associated with decreased cancellous bone density. Moderate elevations in iron stores are not only found in astronauts, but also naturally occur in healthy human populations. This healthy population with elevated iron stores may also have increased levels of oxidative stress in the body. Elevated levels of oxidative stress not only increase one’s risk for accelerated bone loss, but also the risk of developing other chronic diseases such as insulin resistance, hypertension, dyslipidemia, and metabolic syndrome.

Yuen, Evelyn P

2013-05-01T23:59:59.000Z

360

Parameterizations for the Absorption of Solar Radiation by O2 and CO2 with Application to Climate Studies  

Science Conference Proceedings (OSTI)

Simple and accurate parameterizations have been developed for computing the absorption of solar radiation due to O2 and CO2. The parameterizations are based on the findings that temperature has a minimal effect on the absorption and that the one-...

Ming-Dah Chou

1990-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Real Time and In Situ Studies of Materials in a Radiation Environment  

Science Conference Proceedings (OSTI)

... as the design of radiation resistant materials, synthesis mechanisms for Actinides and Technetium compounds, and phase diagrams for metallic nuclear fuels.

362

Lack of effects of atomic bomb radiation on genetic instability of tandem-repetitive elements in human germ cells  

Science Conference Proceedings (OSTI)

In a pilot study to detect the potential effects of atomic bomb radiation on germ-line instability, we screened 64 children from 50 exposed families and 60 from 50 control families for mutations at six minisatellite loci by using Southern blot analysis with Pc-1, {lambda}TM-18, ChdTC-15, p{lambda}g3, {lambda}MS-1, and CEB-1 probes. In the exposed families, one or both parents received a radiation dose >0.01 Sv. Among the 64 children, only one child had parents who were both exposed. Thus, of a total of 128 gametes that produced the 64 children, 65 gametes were derived from exposed parents and 63 were from unexposed parents, the latter being included in a group of 183 unexposed gametes used for calculating mutation rates. The average parental gonadal dose for the 65 gametes was 1.9 Sv. We detected a total of 28 mutations at the p{lambda}g3, {lambda}MS-1, and CEB-1 loci, but no mutations at the Pc-1, {lambda}TM-18, and ChdTC-15 loci. We detected 6 mutations in 390 alleles of the 65 exposed gametes and 22 mutations in 1098 alleles of the 183 gametes from the unexposed parents. The mean mutation rate per locus per gamete in these six minisatellite loci was 1.5% in the exposed parents and 2.0% in the unexposed parents. We observed no significant difference in mutation rates in the children of the exposed and the unexposed parents (P = .37, Fisher`s exact probability test). 38 refs., 1 fig., 5 tabs.

Kodaira, Mieko; Satoh, Chiyoko [Radiation Effects Research Foundation, Hiroshima (Japan); Hiyama, Keiko [Radiation Effects Research Foundation, Hiroshima (Japan)]|[Hiroshima Univ. School of Medicine (Japan)] [and others

1995-12-01T23:59:59.000Z

363

Effectiveness of a clinical intervention in improving pain control in outpatients with cancer treated by radiation therapy  

SciTech Connect

Purpose: To determine the effectiveness of a multicomponent clinical intervention to reduce pain in outpatients with cancer. Methods and Materials: Sixty-four patients were randomly assigned to receive either a clinical intervention including an information session, the use of a pain diary, and the possibility to contact a physician to adjust the pain medication, or the usual treatment of pain by the staff radiation oncologist. All patients reported their average and worst pain levels at baseline and 2 and 3 weeks after the start of the intervention. Results: The study groups were similar with respect to their baseline characteristics and pain levels at randomization. After 3 weeks, the average and worst pain experienced by patients randomized to the clinical intervention group was significantly inferior to the average pain experienced by patients in the control group (2.9/10 vs. 4.4/10 and 4.2/10 vs. 5.5/10, respectively). Results showed that the experimental group patients decreased their pain levels more than the control group patients did over time. Conclusion: An intervention including patient education, a pain diary, and defining a procedure for therapeutic adjustments can be effective to improve pain relief in outpatients with cancer.

Vallieres, Isabelle [Department of Radiation Oncology, Centre Hospitalier Universitaire de Quebec-Hotel-Dieu de Quebec, Quebec City (Canada)]. E-mail: isabelle.vallieres@mail.chuq.qc.ca; Aubin, Michele [Department of Family Medicine, Laval Hospital, Quebec City, Quebec (Canada); Blondeau, Lucie [Department of Radiation Oncology, Centre Hospitalier Universitaire de Quebec-Hotel-Dieu de Quebec, Quebec City (Canada); Simard, Serge [Research Centre of Laval Hospital, Laval University, Sainte-Foy, Quebec (Canada); Giguere, Anik [Palliative Care Research Team, Laval University, Quebec City, Quebec (Canada)

2006-09-01T23:59:59.000Z

364

Hydrogen Water Chemistry Effects on BWR Radiation Buildup: Volume 1: Laboratory Results and Plant Data  

Science Conference Proceedings (OSTI)

Diverse laboratory experiments and a review of the most recent dose rate data from operating plants identify some of the key factors responsible for the increase in shutdown radiation fields at a number of BWRs following implementation of hydrogen water chemistry (HWC). These insights suggest strategies to minimize radiation field increases under HWC and to avoid possible problems during chemical decontamination.

1994-12-29T23:59:59.000Z

365

he Impact of Primary Marine Aerosol on Atmospheric Chemistry, Radiation and Climate: A CCSM Model Development Study  

SciTech Connect

This project examined the potential large-scale influence of marine aerosol cycling on atmospheric chemistry, physics and radiative transfer. Measurements indicate that the size-dependent generation of marine aerosols by wind waves at the ocean surface and the subsequent production and cycling of halogen-radicals are important but poorly constrained processes that influence climate regionally and globally. A reliable capacity to examine the role of marine aerosol in the global-scale atmospheric system requires that the important size-resolved chemical processes be treated explicitly. But the treatment of multiphase chemistry across the breadth of chemical scenarios encountered throughout the atmosphere is sensitive to the initial conditions and the precision of the solution method. This study examined this sensitivity, constrained it using high-resolution laboratory and field measurements, and deployed it in a coupled chemical-microphysical 3-D atmosphere model. First, laboratory measurements of fresh, unreacted marine aerosol were used to formulate a sea-state based marine aerosol source parameterization that captured the initial organic, inorganic, and physical conditions of the aerosol population. Second, a multiphase chemical mechanism, solved using the Max Planck Institute for Chemistryâ??s MECCA (Module Efficiently Calculating the Chemistry of the Atmosphere) system, was benchmarked across a broad set of observed chemical and physical conditions in the marine atmosphere. Using these results, the mechanism was systematically reduced to maximize computational speed. Finally, the mechanism was coupled to the 3-mode modal aerosol version of the NCAR Community Atmosphere Model (CAM v3.6.33). Decadal-scale simulations with CAM v.3.6.33, were run both with and without reactive-halogen chemistry and with and without explicit treatment of particulate organic carbon in the marine aerosol source function. Simulated results were interpreted (1) to evaluate influences of marine aerosol production on the microphysical properties of aerosol populations and clouds over the ocean and the corresponding direct and indirect effects on radiative transfer; (2) atmospheric burdens of reactive halogen species and their impacts on O3, NOx, OH, DMS, and particulate non-sea-salt SO42-; and (3) the global production and influences of marine-derived particulate organic carbon. The model reproduced major characteristics of the marine aerosol system and demonstrated the potential sensitivity of global, decadal-scale climate metrics to multiphase marine-derived components of Earthâ??s troposphere. Due to the combined computational burden of the coupled system, the currently available computational resources were the limiting factor preventing the adequate statistical analysis of the overall impact that multiphase chemistry might have on climate-scale radiative transfer and climate.

Keene, William C. [University of Virginia] [University of Virginia; Long, Michael S. [University of Virginia] [University of Virginia

2013-05-20T23:59:59.000Z

366

Human radiation studies: Remembering the early years. Oral history of Merril Eisenbud, January 26, 1995  

SciTech Connect

Merril Eisenbud was interviewed on January 26, 1995 by representatives of the US DOE Office of Human Radiation Experiments. Following a brief biographical sketch, Mr. Eisenbud relates his remembrances as the AEC`s first industrial hygienist, the setting up of AEC`s Health and Safety Laboratory, monitoring radioactive fallout, and use or exposure of humans to radiation.

1995-05-01T23:59:59.000Z

367

"We will die and become science" : the production of invisibility and public knowledge about Chernobyl radiation effects in Belarus  

E-Print Network (OSTI)

radiophobia’(fear of radiation), and their fear was notblamed on radiophobia (fear of radiation), stress followinganxiety and radiophobia (fear of radiation). Methodological

Kuchinskaya, Olga

2007-01-01T23:59:59.000Z

368

Effective photoelectric converters of ultraviolet radiation with graded-gap ZnS-based layers  

SciTech Connect

The use of ultrathin ({approx}10 nm) stable p-Cu{sub 1.8}S films as a transparent component of the p-Cu{sub 1.8}S-n-ZnS heterojunction as well as of the graded-gap layers made it possible to obtain effective photoconverters of ultraviolet radiation. The results of examination of the properties of photoactive Cu{sub 1.8}S-ZnS junctions grown on the CdS or CdSe substrates with intermediate graded-gap layers CdS-Zn{sub x}Cd{sub 1-x}S or CdSe-(ZnS){sub x}(CdSe){sub 1-} {sub x}, respectively, are presented. With the correct selection of parameters of the substrates, the graded-gap layers allows one to attain the optimal characteristics of the p-n junction, to realize high electric fields at the Cu{sub 1.8}S-ZnS contact, and to solve the problem of fabrication of the back ohmic contact to ZnS without additional doping of all components of the heterostructure with a foreign impurity. Varying the thickness of a thin ZnS layer, it is possible to control the extension of the space charge in the graded-gap layer and thereby to control the long-wavelength edge of photoconverter sensitivity.

Bobrenko, Yu. N.; Pavelets, S. Yu., E-mail: pavelets@voliacable.com; Pavelets, A. M. [National Academy of Sciences of Ukraine, Lashkarev Institute of Semiconductor Physics (Ukraine)

2009-06-15T23:59:59.000Z

369

Activities of the National Academy of Sciences in relation to the Radiation Effects Research Foundation. Annual performance report, June 1, 1991--May 31, 1992  

SciTech Connect

This progress report relates progress in the various research projects evaluating the late health effects, both somatic and genetic, resulting from radiation exposure of the survivors of the atomic bombs at Hiroshima and Nagasaki, Japan. Considerable progress has been made in the collection and utilization of the various epidemiological data bases. These include the Life Span Study, (LSS) cohort, the Adult Health Study (AHS) cohort, the In Utero cohort, the leukemia registry and the F-1 Study population. Important progress has been made in using RERF Tumor and Tissue Registry records for evaluation of cancer incidence and radiation risk estimates for comparison with cancer mortality and risk in the LSS cohort. At the present time, a manuscript on the incidence of solid tumors (1950-1987) is undergoing internal and external review for publication as an RERF Technical report (TR) and for publication in a peer-reviewed scientific journal. In addition, manuscripts are in preparation on (1) a comprehensive report on the incidence of hematological cancers, including analysis of leukemia by cell type (1950-1987), (2) a general description of Tumor Registry operations and (3) a comparison of incidence- and mortality-based estimates of radiation risk in the LSS cohort.

Edington, C.W.

1992-06-01T23:59:59.000Z

370

Human radiation studies: Remembering the early years. Oral history of Oncologist Helen Vodopick, M.D., December 28, 1994  

SciTech Connect

This report is a transcript of an interview with Dr. Helen Vodopick by representatives of the US DOE Office of Human Radiation Experiments. Dr. Vodopick was chosen for this interview because of her involvement with the Oak Ridge Institute of Nuclear Studies (ORINS) and Oak Ridge Associated Universities (ORAU) experimental cancer-therapy program involving total-body irradiation. After a short biographical sketch Dr. Vodopick relates her remembrances of the Medium-Exposure-Rate Total Body Irradiator (METBI), ORINS radioisotope tracer studies, treatment of cancer patients with the METBI, radiation treatment for leukemia patients, bone marrow treatment of leukemia, the Low-Exposure-Rate Total Body Irradiation (LETBI), treatment of radiation accident victims at ORAU, research with radioactive phosphorus and sulfur, and public opinion issues.

1995-08-01T23:59:59.000Z

371

Periodicity, Thermal Effects, and Vacuum Force: Rotation in Random Classical Zero-Point Radiation  

E-Print Network (OSTI)

We show that, for a detector rotating in a random classical zero-point electromagnetic or massless scalar field at zero temperature, thermal effects exist. The rotating reference system is constructed as an infinite set of Frenet-Seret tetrads so that the detector is at rest in a tetrad at each proper time. Frequency spectrum of correlation functions contains the Planck thermal factor with temperature $T_{rot} = \\frac{\\hbar \\Omega}{2 \\pi k_B} $. The energy density the rotating detector observes is proportional to the sum of energy densities of Planck's spectrum at the temperature $T_{rot}$ and zero-point radiation. The proportionality factor is $2/3 (4 \\gamma^2 -1)$ for an EMF and $2/9 (4 \\gamma^2 -1)$ for a MSF, where $\\gamma = (1 - (\\frac{\\Omega r}{c})^2)^{-1/2}$, and r is a rotation radius. The origin of these thermal effects is the periodicity of the correlation functions and their discrete spectrum, both following rotation with angular velocity $\\Omega$. The thermal energy can also be interpreted as a source of a vacuum force (VF) applied to the rotating detector from the vacuum field. The VF depends on the size of neither the charge nor the mass, like the force in the Casimir model for a charged particle, but, contrary to the last one, VF is attractive and directed to the center of the circular orbit. VF infinitely grows in magnitude with orbit radius. The orbits with a radius greater than $c/ \\Omega$ do not exist because the returning VF becomes infinite. On the uttermost orbit with the radius $c / \\Omega$, a linear velocity of the rotating particle would have become c. The VF becomes very small and proportional to radius when r is very small. Such VF dependence on radius, at large and small radii, can be associated respectively with so called confinement and asymptotic freedom, known in quantum chromodynamics, and provide a new explanation for them.

Yefim Semenovitch Levin

2010-03-23T23:59:59.000Z

372

Dynamics of Line-Driven Disk Winds in Active Galactic Nuclei II: Effects of Disk Radiation  

E-Print Network (OSTI)

We explore consequences of a radiation driven disk wind model for mass outflows from active galactic nuclei (AGN). We performed axisymmetric time-dependent hydrodynamic calculations using the same computational technique as Proga, Stone and Kallman (2000). We test the robustness of radiation launching and acceleration of the wind for relatively unfavorable conditions. In particular, we take into account the central engine radiation as a source of ionizing photons but neglect its contribution to the radiation force. Additionally, we account for the attenuation of the X-ray radiation by computing the X-ray optical depth in the radial direction assuming that only electron scattering contributes to the opacity. Our new simulations confirm the main result from our previous work: the disk atmosphere can 'shield' itself from external X-rays so that the local disk radiation can launch gas off the disk photosphere. We also find that the local disk force suffices to accelerate the disk wind to high velocities in the radial direction. This is true provided the wind does not change significantly the geometry of the disk radiation by continuum scattering and absorption processes; we discuss plausibility of this requirement. Synthetic profiles of a typical resonance ultraviolet line predicted by our models are consistent with observations of broad absorption line (BAL) QSOs.

D. Proga; T. R. Kallman

2004-08-16T23:59:59.000Z

373

Measuring Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Measurement Activity SI Units and Prefixes Conversions Safety Around Radiation Sources Types of Radiation Exposure Managing Radiation Emergencies Procedure Demonstration...

374

Pilot Study Of Impedance-controlled Microcurrent Therapy For Managing Radiation-induced Fibrosis In Head-and-neck Cancer Patients  

E-Print Network (OSTI)

Pilot Study Of Impedance-controlled Microcurrent Therapy For Managing Radiation-induced Fibrosis In Head-and-neck Cancer Patients

Lennox, A J

2002-01-01T23:59:59.000Z

375

Reproductive Status at First Diagnosis Influences Risk of Radiation-Induced Second Primary Contralateral Breast Cancer in the WECARE Study  

Science Conference Proceedings (OSTI)

Purpose: Our study examined whether reproductive and hormonal factors before, at the time of, or after radiation treatment for a first primary breast cancer modify the risk of radiation-induced second primary breast cancer. Methods and Materials: The Women's Environmental, Cancer and Radiation Epidemiology (WECARE) Study is a multicenter, population-based study of 708 women (cases) with asynchronous contralateral breast cancer (CBC) and 1399 women (controls) with unilateral breast cancer. Radiotherapy (RT) records, coupled with anthropomorphic phantom simulations, were used to estimate quadrant-specific radiation dose to the contralateral breast for each patient. Rate ratios (RR) and 95% confidence intervals (CI) were computed to assess the relationship between reproductive factors and risk of CBC. Results: Women who were nulliparous at diagnosis and exposed to {>=}1 Gy to the contralateral breast had a greater risk for CBC than did matched unexposed nulliparous women (RR = 2.2; 95% CI, 1.2-4.0). No increased risk was seen in RT-exposed parous women (RR = 1.1; 95% CI, 0.8-1.4). Women treated with RT who later became pregnant (8 cases and 9 controls) had a greater risk for CBC (RR = 6.0; 95% CI, 1.3-28.4) than unexposed women (4 cases and 7 controls) who also became pregnant. The association of radiation with risk of CBC did not vary by number of pregnancies, history of breastfeeding, or menopausal status at the time of first breast cancer diagnosis. Conclusion: Nulliparous women treated with RT were at an increased risk for CBC. Although based on small numbers, women who become pregnant after first diagnosis also seem to be at an increased risk for radiation-induced CBC.

Brooks, Jennifer D., E-mail: brooksj@mskcc.org [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Boice, John D. [International Epidemiology Institute, Rockville, MD and Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Vanderbilt School of Medicine, Nashville, TN (United States)] [International Epidemiology Institute, Rockville, MD and Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Vanderbilt School of Medicine, Nashville, TN (United States); Stovall, Marilyn [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Reiner, Anne S. [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)] [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Bernstein, Leslie [Division of Cancer Etiology, Department of Population Sciences, Beckman Research Institute and City of Hope Comprehensive Cancer Center, Duarte, CA (United States)] [Division of Cancer Etiology, Department of Population Sciences, Beckman Research Institute and City of Hope Comprehensive Cancer Center, Duarte, CA (United States); John, Esther M. [Cancer Prevention Institute of California, Fremont, CA, and Stanford University School of Medicine and Stanford Cancer Institute, Stanford, CA (United States)] [Cancer Prevention Institute of California, Fremont, CA, and Stanford University School of Medicine and Stanford Cancer Institute, Stanford, CA (United States); Lynch, Charles F. [Department of Epidemiology, University of Iowa, Iowa City, IA (United States)] [Department of Epidemiology, University of Iowa, Iowa City, IA (United States); Mellemkjaer, Lene [Institute of Cancer Epidemiology, Danish Cancer Society, Copenhagen (Denmark)] [Institute of Cancer Epidemiology, Danish Cancer Society, Copenhagen (Denmark); Knight, Julia A. [Dalla Lana School of Public Health, University of Toronto and Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario (Canada)] [Dalla Lana School of Public Health, University of Toronto and Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario (Canada); Thomas, Duncan C.; Haile, Robert W. [Department of Preventive Medicine, University of Southern California, Los Angeles, CA (United States)] [Department of Preventive Medicine, University of Southern California, Los Angeles, CA (United States); Smith, Susan A. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Capanu, Marinela; Bernstein, Jonine L. [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)] [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Shore, Roy E. [Department of Environmental Medicine, New York University, New York, NY (United States) [Department of Environmental Medicine, New York University, New York, NY (United States); Radiation Effects Research Foundation, Hiroshima (Japan)

2012-11-15T23:59:59.000Z

376

LET dependence of radiation-induced bystander effects using human prostate tumor cells  

E-Print Network (OSTI)

In the past fifteen years, evidence provided by many independent research groups have indicated higher numbers of cells exhibiting damage than expected based on the number of cells traversed by the radiation. This phenomenon ...

Anzenberg, Vered

2008-01-01T23:59:59.000Z

377

An Effective, Economic, Aspirated Radiation Shield for Air Temperature Observations and Its Spatial Gradients  

Science Conference Proceedings (OSTI)

This paper presents the design and evaluates the performance of a double-walled electrically aspirated radiation shield for thermometers measuring air temperature and its gradients in the atmospheric surface layer. Tests were performed to quantify ...

Christoph K. Thomas; Alexander R. Smoot

2013-03-01T23:59:59.000Z

378

Overlap of Solar and Infrared Spectra and the Shortwave Radiative Effect of Methane  

Science Conference Proceedings (OSTI)

This paper focuses on two shortcomings of radiative transfer codes commonly used in climate models. The first aspect concerns the partitioning of solar versus infrared spectral energy. In most climate models, the solar spectrum comprises ...

J. Li; C. L. Curry; Z. Sun; F. Zhang

2010-07-01T23:59:59.000Z

379

Effect of Spatial Organization on Solar Radiative Transfer in Three-Dimensional Idealized Stratocumulus Cloud Fields  

Science Conference Proceedings (OSTI)

To relate the error associated with 1D radiative calculations to the geometrical scales of cloud organization and/or in-cloud optical inhomogeneities, a new idealized methodology, based on a Fourier statistical technique, has been developed. ...

F. Di Giuseppe; A. M. Tompkins

2003-08-01T23:59:59.000Z

380

Effects of Ocean Biology on the Penetrative Radiation in a Coupled Climate Model  

Science Conference Proceedings (OSTI)

The influence of phytoplankton on the seasonal cycle and the mean global climate is investigated in a fully coupled climate model. The control experiment uses a fixed attenuation depth for shortwave radiation, while the attenuation depth in the ...

Patrick Wetzel; Ernst Maier-Reimer; Michael Botzet; Johann Jungclaus; Noel Keenlyside; Mojib Latif

2006-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Winter study of power plant effects  

Science Conference Proceedings (OSTI)

As a part of DOE's Meteorological Effects of Thermal Energy Releases (METER) program a field study was undertaken at the Bowen Electric Generating Plant (Plant Bowen) in December 1979. The study was a joint endeavor of Battelle Pacific Northwest Laboratories (PNL), Pennsylvania State University (PSU), and Oak Ridge National Laboratory (ORNL) with the main objective of determining the effects of the plant's smokestack effluents on aerosol characteristics and precipitation chemistry. Other objectives included studies of cooling tower temperature and humidity (T/h) plumes and drift drop concentrations. Conducted over a period of three weeks, the study involved an instrumented aircraft, pilot balloons, a tethered balloon system, a dense network of wetfall chemistry collectors and numerous ground- and tower-based meteorological instruments. Rainfall samples collected during the precipitation event of December 13, 1979, revealed some evidence of plume washout. The tethered balloon flights rarely detected the faint presence of the T/h plumes while the airborne measurements program concentrated on the study of SO/sub 2/ to sulfate conversion. A series of plume observations confirmed the suitability of the plant's windset for plume direction determinations.

Patrinos, A.A.N.

1980-10-01T23:59:59.000Z

382

The effects of diet and ionizing radiation on azoxymethane induced colon carcinogenesis  

E-Print Network (OSTI)

The ability of ionizing radiation to enhance colon carcinogenesis and the role of diet in this process has not been documented. We hypothesized that radiation would enhance the formation of aberrant crypt foci, ACF, known precursor lesions to colon cancer, by suppressing apoptosis and upregulating proliferation in colonocytes. Diets contained a combination of fish oil or corn oil and either pectin or cellulose. We exposed 40 male Sprague-Dawley rats to 1 Gy ionizing radiation (1 GeV Fe) 10 d prior to injection with AOM. Colons were resected at the promotion stage of carcinogenesis (7 wk post initial injection) and assayed for ACF and apoptosis. Radiation treatment increased (P=0.0327) the incidence of high multiplicity ACF (foci with four or more aberrant crypts) and decreased (P=0.0340) the apoptotic index compared to non-irradiated rats. Radiation also resulted in an increase (PACF compared to the corn oil treatment. Dietary pectin significantly increased (P=0.0204) the apoptotic index compared to cellulose treatment. These data suggest that ionizing radiation can work synergistically with AOM and increase the formation of high-multiplicity ACF, upregulate cellular proliferation and decrease apoptosis in colonocytes. The data also suggest that diets containing fish oil and pectin may protect against colon cancer by increasing apoptosis and reducing the formation of high multiplicity ACF.

Mann, John Clifford

2005-08-01T23:59:59.000Z

383

Potential of Hybrid Computational Phantoms for Retrospective Heart Dosimetry After Breast Radiation Therapy: A Feasibility Study  

SciTech Connect

Purpose: Current retrospective cardiovascular dosimetry studies are based on a representative patient or simple mathematic phantoms. Here, a process of patient modeling was developed to personalize the anatomy of the thorax and to include a heart model with coronary arteries. Methods and Materials: The patient models were hybrid computational phantoms (HCPs) with an inserted detailed heart model. A computed tomography (CT) acquisition (pseudo-CT) was derived from HCP and imported into a treatment planning system where treatment conditions were reproduced. Six current patients were selected: 3 were modeled from their CT images (A patients) and the others were modelled from 2 orthogonal radiographs (B patients). The method performance and limitation were investigated by quantitative comparison between the initial CT and the pseudo-CT, namely, the morphology and the dose calculation were compared. For the B patients, a comparison with 2 kinds of representative patients was also conducted. Finally, dose assessment was focused on the whole coronary artery tree and the left anterior descending coronary. Results: When 3-dimensional anatomic information was available, the dose calculations performed on the initial CT and the pseudo-CT were in good agreement. For the B patients, comparison of doses derived from HCP and representative patients showed that the HCP doses were either better or equivalent. In the left breast radiation therapy context and for the studied cases, coronary mean doses were at least 5-fold higher than heart mean doses. Conclusions: For retrospective dose studies, it is suggested that HCP offers a better surrogate, in terms of dose accuracy, than representative patients. The use of a detailed heart model eliminates the problem of identifying the coronaries on the patient's CT.

Moignier, Alexandra, E-mail: alexandra.moignier@irsn.fr [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France)] [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France); Derreumaux, Sylvie; Broggio, David; Beurrier, Julien [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France)] [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France); Chea, Michel; Boisserie, Gilbert [Groupe Hospitalier Pitie Salpetriere, Service de Radiotherapie, Paris (France)] [Groupe Hospitalier Pitie Salpetriere, Service de Radiotherapie, Paris (France); Franck, Didier; Aubert, Bernard [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France)] [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France); Mazeron, Jean-Jacques [Groupe Hospitalier Pitie Salpetriere, Service de Radiotherapie, Paris (France)] [Groupe Hospitalier Pitie Salpetriere, Service de Radiotherapie, Paris (France)

2013-02-01T23:59:59.000Z

384

DOE Order Self Study Modules - 10 CFR 835 Occupational Radiation Protection  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

10 CFR 835 10 CFR 835 OCCUPATIONAL RADIATION PROTECTION NATIONAL NUCLEAR SECURITY ADMINISTRATION LEARNING AND CAREER DEVELOPMENT DEPARTMENT Change No: 1 10 CFR 835 Level: Familiar Date:11/1/08 1 10/1/08 10 CFR 835 OCCUPATIONAL RADIATION PROTECTION FAMILIAR LEVEL ___________________________________________________________________________ OBJECTIVES Given the familiar level of this module and the resources, you will be able to perform the following: 1. State the scope of 10 CFR 835. 2. Define the following terms. annual limit on intake bioassay contamination area derived air concentration high contamination area radiation weighting factor 3. State the requirements of the general rule. 4. State the radiation protection program requirements. 5. State the requirements of the internal audit.

385

PHOTOEMISSION STUDIES OF CLEAN AND ADSORBATE COVERED METAL SURFACES USING SYNCHROTRON AND UV RADIATION SOURCES  

E-Print Network (OSTI)

c J/ l TABLE II, SSRL 4 Beam Line - Monochroraatorhave made on the A oratory (SSRL). beam line at the Stanfordas they pertain to the SSRL (Stanford Synchrotron Radiation

Apai II, jG.R.

2011-01-01T23:59:59.000Z

386

On the Use of Earth Radiation Budget Statistics for Studies of Clouds and Climate  

Science Conference Proceedings (OSTI)

Daily observations of albedo and outgoing terrestrial radiation derived from NOAA Scanning Radiometer measurements are used to relate cloudiness variations to regional features of the general circulation and to estimate the relative importance of ...

Dennis L. Hartmann; David A. Short

1980-06-01T23:59:59.000Z

387

Medium-induced multi-photon radiation  

E-Print Network (OSTI)

We study the spectrum of multi-photon radiation off a fast quark in medium in the BDMPS/ASW approach. We reproduce the medium-induced one-photon radiation spectrum in dipole approximation, and go on to calculate the two-photon radiation in the Moli\\`{e}re limit. We find that in this limit the LPM effect holds for medium-induced two-photon ladder emission.

Ma, Hao; Tywoniuk, Konrad

2011-01-01T23:59:59.000Z

388

Studies on Pentoxifylline and Tocopherol Combination for Radiation-Induced Heart Disease in Rats  

SciTech Connect

Purpose: To investigate whether the application of pentoxifylline (PTX) and tocopherol l (Vit. E) could modify the development of radiation-induced heart disease and downregulate the expression of transforming growth factor (TGF)-{beta}1mRNA in rats. Methods and Materials: A total of 120 Sprague-Dawley rats were separated into four groups: control group, irradiated group, experimental group 1, and experiment group 2. Supplementation was started 3 days before irradiation; in experimental group 1, injection of PTX (15 mg/kg/d) and Vit. E (5.5 mg/kg/d) continued till the 12th week postirradiation, whereas in experimental group 2 it was continued until the 24th week postirradiation. All rats were administrated a single dose of 20 Gy irradiation to the heart except the control group. Histopathologic evaluation was performed at various time points (Days 1, 2, 4, 8, and 12 and 24th week) up to 24 weeks after irradiation. Changes of levels of TGF-{beta}1 mRNA expression were also investigated at the same time points using competitive polymerase chain reaction. Results: Compared with the irradiated group, levels of TGF-{beta}1 mRNA of the rat hearts were relatively low in the two experimental groups on the 12th week postirradiation. In experimental group 1, there was a rebound expression of TGF-{beta}1 mRNA on the 24th week postirradiation, whereas that of the experimental group 2 remained low (p < 0.05). The proportions of collagen fibers of the two experimental groups were lower than that of irradiated group (p < 0.05). A rebound could be observed in the experimental group 1. Conclusion: PTX and Vit. E downregulated the expression of TGF-{beta}1 mRNA. The irradiated rat hearts showed a marked pathologic response to the drugs. The withdrawal of drugs in the 12th week postirradiation could cause rebound effects of the development of fibrosis.

Liu Hui [State Key Laboratory of Oncology in South China, Guangzhou, Guangdong (China); Department of Radiotherapy, Cancer Center, Sun Yat-sen University, Guangzhou, Guangdong (China); Xiong Mai [Department of Cardiac Surgery, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong (China); Xia Yunfei; Cui Nianji; Lu Rubiao [State Key Laboratory of Oncology in South China, Guangzhou, Guangdong (China); Department of Radiotherapy, Cancer Center, Sun Yat-sen University, Guangzhou, Guangdong (China); Deng Ling [State Key Laboratory of Oncology in South China, Guangzhou, Guangdong (China); Department of Pathology, Cancer Center, Sun Yat-sen University, Guangzhou, Guangdong (China); Lin Yuehao [State Key Laboratory of Oncology in South China, Guangzhou, Guangdong (China); Clinical Laboratory, Cancer Center, Sun Yat-sen University, Guangzhou, Guangdong (China); Rong Tiehua [State Key Laboratory of Oncology in South China, Guangzhou, Guangdong (China); Department of Thoracic Surgery, Cancer Center, Sun Yat-sen University, Guangzhou, Guangdong (China)], E-mail: esophagus2003@yahoo.com.cn

2009-04-01T23:59:59.000Z

389

Periodicity, Thermal Effects, and Vacuum Force: Rotation in Random Classical Zero-Point Radiation  

E-Print Network (OSTI)

We show that for a detector rotating in a random classical zero-point electromagnetic or massless scalar field at T=0 thermal effects exist. The rotating reference system is constructed as an infinite set of Frenet-Seret tetrads defined so that the detector is at rest in a tetrad at each proper time. Correlation functions, more exactly their frequency spectrum, contain the Planck thermal factor, and the energy density the rotating detector observes is proportional to the sum of energy densities of Planck's spectrum at the temperature T_rot = \\hbar \\Omega / (2 \\pi k_B) and zero-point radiation. The proportionality factor is (2/3)(4\\gamma^2 - 1) for an electromagnetic field and (2/9)(4\\gamma^2 - 1) for a massless scalar field, where \\gamma = (1 - (\\Omega r/c)^2)^(-1/2), and r is a detector rotation radius. The origin of these thermal effects is the periodicity of the correlation functions and their discrete spectrum, both following rotation with angular velocity \\Omega. The thermal energy can also be interpreted as a source of a vacuum force, f_vac, applied to the rotating detector from the vacuum field. The f_vac depends on the size of neither the charge nor the mass, like the force in the Casimir model for a charged particle, but, contrary to the last one, it is directed to the center of the circular orbit. The f_vac infinitely grows by magnitude when r \\to r_0 = c/\\Omega, with a fixed \\Omega. The orbits with a radius greater than r_0 do not exist simply because the returning vacuum force becomes infinite. On the uttermost orbit with the radius r_0, a linear velocity of the rotating particle would have become c. The f_vac becomes very small and proportional to r when r is small, r << c/\\aOmega. Such vacuum force dependence on radius, at large and small r, can be associated respectively with so called confinement and asymptotic freedom, known in QCD, and provide a new explanation for them.

Yefim Semenovitch Levin

2010-03-22T23:59:59.000Z

390

The observed relationship between the occurrence of acute radiation effects and leukemia mortality among A-bomb survivors  

SciTech Connect

In an analysis of a follow-up study of a fixed population of 73,330 atomic bomb survivors in Hiroshima and Nagasaki, the slope of an estimated dose response between ionizing radiation and leukemia mortality was found to be steeper (P less than 0.002), by a factor of 2.4, among those who reported epilation within 60 days of the bombings, compared to those who did not experience this sign of acute radiation exposure. The strength of this empirical finding as evidence of biological association in individual radiosensitivity for these two end points is studied here. The major factor complicating the interpretation of this finding as evidence of such an association is the degree of imprecision of the radiation dosimetry system used in assignment of radiation doses to the A-bomb survivors. Using models recently suggested for dealing with dosimetry errors in epidemiological analysis of the A-bomb survivor data, the sensitivity of the apparent association between leukemia mortality and severe epilation to the assumed level of dosimetry error is investigated.

Neriishi, K.; Stram, D.O.; Vaeth, M.; Mizuno, S.; Akiba, S. (Radiation Effects Research Foundation, Hiroshima (Japan))

1991-02-01T23:59:59.000Z

391

Polarization of Cerenkov radiation in anisotropic media  

SciTech Connect

Using the method of Stokes parameters, we examine the polarization of Cerenkov radiation in anisotropic media. The study reveals that the radiation is totally polarized and that circular polarization is purely a quantum effect. We examine two cases; when the particle initially moves along the optical axis and when the particle initially moves perpendicular to the optical axis.

Orisa, B.D. [Moi Univ., Eldoret (Kenya)

1995-10-01T23:59:59.000Z

392

A Phase I Study of the Combination of Sorafenib With Temozolomide and Radiation Therapy for the Treatment of Primary and Recurrent High-Grade Gliomas  

SciTech Connect

Purpose: Despite recent advances in the management of high-grade and recurrent gliomas, survival remains poor. Antiangiogenic therapy has been shown to be efficacious in the treatment of high-grade gliomas both in preclinical models and in clinical trials. We sought to determine the safety and maximum tolerated dose of sorafenib when combined with both radiation and temozolomide in the primary setting or radiation alone in the recurrent setting. Methods and Materials: This was a preclinical study and an open-label phase I dose escalation trial. Multiple glioma cell lines were analyzed for viability after treatment with radiation, temozolomide, or sorafenib or combinations of them. For patients with primary disease, sorafenib was given concurrently with temozolomide (75 mg/m{sup 2}) and 60 Gy radiation, for 30 days after completion of radiation. For patients with recurrent disease, sorafenib was combined with a hypofractionated course of radiation (35 Gy in 10 fractions). Results: Cell viability was significantly reduced with the combination of radiation, temozolomide, and sorafenib or radiation and sorafenib. Eighteen patients (11 in the primary cohort, 7 in the recurrent cohort) were enrolled onto this trial approved by the institutional review board. All patients completed the planned course of radiation therapy. The most common toxicities were hematologic, fatigue, and rash. There were 18 grade 3 or higher toxicities. The median overall survival was 18 months for the entire population. Conclusions: Sorafenib can be safely combined with radiation and temozolomide in patients with high-grade glioma and with radiation alone in patients with recurrent glioma. The recommended phase II dose of sorafenib is 200 mg twice daily when combined with temozolomide and radiation and 400 mg with radiation alone. To our knowledge, this is the first publication of concurrent sorafenib with radiation monotherapy or combined with radiation and temozolomide.

Den, Robert B., E-mail: robert.den@jeffersonhospital.org [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Kamrava, Mitchell [Radiation Oncology Branch, National Cancer Institute, Bethesda, Maryland (United States)] [Radiation Oncology Branch, National Cancer Institute, Bethesda, Maryland (United States); Sheng, Zhi [Howard Hughes Medical Institute, Programs in Gene Function and Expression and Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (United States)] [Howard Hughes Medical Institute, Programs in Gene Function and Expression and Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (United States); Werner-Wasik, Maria; Dougherty, Erin; Marinucchi, Michelle [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States)] [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Lawrence, Yaacov R. [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States) [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Center for Translational Research in Radiation Oncology, Sheba Medical Center (Israel); Hegarty, Sarah; Hyslop, Terry [Department of Biostatistics, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States)] [Department of Biostatistics, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Andrews, David W.; Glass, Jon [Department of Neurosurgery, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States)] [Department of Neurosurgery, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Friedman, David P. [Department of Radiology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States)] [Department of Radiology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Green, Michael R. [Howard Hughes Medical Institute, Programs in Gene Function and Expression and Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (United States)] [Howard Hughes Medical Institute, Programs in Gene Function and Expression and Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (United States); Camphausen, Kevin [Radiation Oncology Branch, National Cancer Institute, Bethesda, Maryland (United States)] [Radiation Oncology Branch, National Cancer Institute, Bethesda, Maryland (United States); Dicker, Adam P. [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States)] [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States)

2013-02-01T23:59:59.000Z

393

Nonionizing Radiation and HIV  

NLE Websites -- All DOE Office Websites (Extended Search)

Nonionizing Radiation and HIV Name: Flora R Pitchford Location: NA Country: NA Date: NA Question: What are the effects of nonionizing radiation on DNA , RNA or any other cell...

394

The radiation bio-effects of gallum-72 on leukemic cells via a gallium-transferrin complex  

E-Print Network (OSTI)

Improved methods for treatment of leukemia would be advantageous for patients and the medical community. This thesis reports results of a study of the cytotoxicity of radiolabeled transferrin in cultured leukemic cells. K-562 cells, from an erythroleukemic cell line, were grown and growth curves were plotted for characterization. K-562 cells grew logarithmically from approximately 250,000 cells mL?¹ to 700,000 cells mL?¹ and display a doubling time of approximately 20-21 hours. K-562 cells were exposed to x rays at an absorbed dose of 0, 1, 2, and 4 gray. Growth curves were plotted to create a dose response curve. Percent-cell survival in this experiment, and all subsequent experiments, was determined based on the extrapolation of the growth curves to time zero, as compared to a control. An absorbed dose of 1, 2, and 4 gray corresponded to a survival of 77([]14)%, 45([]7.4)% and 20([]2.4)%, respectively. This cell line is relatively resistant to radiation. K-562 cells were exposed to a radioactive gallium-72/stable gallium nitrate mixture to determine the effect gallium-72 decay has on cell survival . Simultaneously, K-562 cells were exposed to a concentration of stable gallium nitrate equivalent to the total gallium concentration, radioactive and stable, of the gallium-72/stable gallium mixture. This allowed a comparison of radioactive and chemotoxic effects due to gallium-72 and stable gallium, respectively. Exposures to gallium-72, at an activity of 184.0 kBq mL?¹, and stable gallium nitrate, at a concentration of 116.7 []M, resulted in a cell survival of 61([]10.5)% and 75([]12. 1)%, respectively. The difference is small when error is taken into consideration. Therefore radioactivity had little effect on cell survival at a specific activity of 6.3 MBq mg?¹. To properly assess the cytotoxicity of gallium-72 the specific activity must be increased. To determine the effect of ape-transferrin on the cytotoxicity of gallium nitrate, K-562 cells were exposed to stable gallium nitrate and increasing amounts of apo-transferrin. Cells exposed to 115.0 []M gallium nitrate exhibited an 82([]8.8)% cell survival compared to 54([]6.9)% following exposure to 115.0 []M gallium nitrate and 3.75 []M apo-transferrin. Apo-transferrin presumably increases cellular uptake of gallium nitrate thereby increasing its cyctotoxic effects.

Forbes, Christen Douglas

1999-01-01T23:59:59.000Z

395

MODELING AND STUDY OF THE CERENKOV EFFECT  

E-Print Network (OSTI)

The studies realized in INRNE (Institute for Nuclear Research and Nuclear Energy) particulary in cosmic rays detection and construction of Muonic Cerenkov Telescope in University of Blagoevgrad [1] shows the need to develop a theoretical model based on observed phenomenon and to refine it for the detection system optimisation. The effect was introduced in EGS4 [2] code system. The first simulations were consecrated to different geometry’s of water tank in total reflection. The model was compared with experimental data realised with gamma source 60 Co using the telescope. A simple atmospheric model is introduced in EGS4. The comparison between CORSIKA [3] and EGS4 codes was realised.

I. Angelov C; E. Duverger A; L. Makovicka A; A. Mishev B; J. Stamenov B

2003-01-01T23:59:59.000Z

396

DOE Order Self Study Modules - DOE G 441.1-1C Radiation Protection Programs Guide  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

41.1-1C 41.1-1C RADIATION PROTECTION PROGRAMS GUIDE NATIONAL NUCLEAR SECURITY ADMINISTRATION LEARNING AND CAREER DEVELOPMENT DEPARTMENT Change No: 1 DOE G 441.1-1C Level: Familiar Date: 12/1/08 1 DOE G 441.1-1C, RADIATION PROTECTION PROGRAMS GUIDE FAMILIAR LEVEL _________________________________________________________________________ OBJECTIVES Given the familiar level of this module and the resources listed below, you will be able to 1. Match radiation protection-related terms to their definitions; 2. Discuss the elements that should be taken into consideration to determine the likelihood of an individual receiving a dose in excess of a regulatory monitoring threshold; 3. Give three examples of criteria that should trigger a formal as-low-as-is-

397

High-let radiation carcinogenesis  

SciTech Connect

Recent results for neutron radiation-induced tumors are presented to illustrate the complexities of the dose-response curves for high-LET radiation. It is suggested that in order to derive an appropriate model for dose-response curves for the induction of tumors by high-LET radiation it is necessary to take into account dose distribution, cell killing and the susceptibility of the tissue under study. Preliminary results for the induction of Harderian gland tumors in mice exposed to various heavy ion beams are presented. The results suggest that the effectiveness of the heavy ion beams increases with increasing LET. The slopes of the dose-response curves for the different high-LET radiations decrease between 20 and 40 rads and therefore comparisons of the relative effectiveness should be made from data obtained at doses below about 20 to 30 rads.

Fry, R.J.M.; Powers-Risius, P.; Alpen, E.L.; Ainsworth, E.J.; Ullrich, R.L.

1982-01-01T23:59:59.000Z

398

Human radiation studies: Remembering the early years. Oral history of Health physicist William J. Bair, Ph.D., October 14, 1994  

SciTech Connect

This report is a transcript of an interview of William J. Blair by representatives of the US DOE Office of Human Radiation Experiments. Dr. Blair was selected for this interview because of of his participation in the University of Rochester Atomic Energy Project and for his radiological inhalation research at Hanford Site. After a brief biographical sketch Dr. Blair discusses his remembrances on a wide rage of topics. Discussions include his graduate studies at Rochester University, use of human subjects at Rochester, his inhalation studies, his limited involvement with human studies, differing biological effects of plutonium 238 and 239, emissions from proposed nuclear-propelled aircraft, cancer research, cleanup at Nevada Test Site and Marshall Islands, impact of Langham studies to understand Plutonium exposure, and AEC controversies and colleagues.

Harrell, D.; Shindledecker, C.

1995-06-01T23:59:59.000Z

399

Radiative effects of a CO/sub 2/ increase: results of a model comparison  

SciTech Connect

A comparison of infrared radiative transfer models is announced. The initial phase is underway, with other phases scheduled through 1984. The results of the ir model comparison will be included in the state-of-the-art report on climate modeling. Although the time scale for completion of the comparison is a few years, significant preliminary results have already been obtained. (PSB)

Luther, F.M.

1982-10-07T23:59:59.000Z

400

Effects of estrogen and gender on cataractogenesis induced by high-LET radiation  

SciTech Connect

Planning for long-duration manned lunar and interplanetary missions requires an understanding of radiation-induced cataractogenesis. Previously, it was demonstrated that low-linear energy transfer (LET) irradiation with 10 Gy of {sup 60}Co {gamma} rays resulted in an increased incidence of cataracts in male rats compared to female rats. This gender difference was not due to differences in estrogen, since male rats treated with the major secreted estrogen 17-{beta}-estradiol (E2) showed an identical increase compared to untreated males. We now compare the incidence and rate of progression of cataracts induced by high-LET radiation in male and female Sprague-Dawley rats. Rats received a single dose of 1 Gy of 600 MeV {sup 56}Fe ions. Lens opacification was measured at 2-4 week intervals with a slit lamp. The incidence and rate of progression of radiation-induced cataracts was significantly increased in the animals in which estrogen was available from endogenous or exogenous sources. Male rats with E2 capsules implanted had significantly higher rates of progression compared to male rats with empty capsules implanted (P = 0.025) but not compared to the intact female rats. These results contrast with data obtained after low-LET irradiation and suggest the possibility that the different types of damage caused by high- and low-LET radiation may be influenced differentially by steroid sex hormones.

Henderson, M.A.; Rusek, A.; Valluri, S.; Garrett, J.; Lopez, J.; Caperell-Grant, A.; Mendonca, M.; Bigsby, R.; Dynlacht, J.

2010-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

The Effects of Radiative Cooling in a Cloud-Topped Mixed Layer  

Science Conference Proceedings (OSTI)

The sensitivity of models of cloud-topped mixed layers to various specifications of the radiative cooling rate near the cloud top is investigated. It is found that for the “dry cloud” case an assumed distributed cooling rate leads to a shallower ...

Douglas K. Lilly; Wayne H. Schubert

1980-02-01T23:59:59.000Z

402

J. Phycol. 34, 118125 (1998) TEMPERATURE DEPENDENCE OF UV RADIATION EFFECTS ON  

E-Print Network (OSTI)

- rayi West and West isolated from a meltwater pond on the McMurdo Ice Shelf was grown in unialgal batch photosynthesis (Vincent and Roy 1993, Williamson 1995). Solar UV-A radiation (320­ 400 nm) has also been-damage-repair mechanisms (Que- sada et al. 1995). Cold water temperatures are a characteristic fea- ture of the polar

Vincent, Warwick F.

403

Effects of Cloudiness on the High-Latitude Surface Radiation Budget  

Science Conference Proceedings (OSTI)

Ten years of hourly data on radiation, cloud and temperature collected at Resolute, Canada (75°N) show that with respect to clear skies: (i) clouds of all types, heights and extents heat the surface when it is snow-covered; (ii) low clouds ...

J. Graham Cogley; A. Henderson-Sellers

1984-05-01T23:59:59.000Z

404

Multi-mutational model for cancer based on age-time patterns of radiation effects: 2. Biological aspects  

SciTech Connect

Biological properties of relevance when modeling cancers induced in the atom bomb survivors include the wide distribution of the induced cancers across all organs, their biological indistinguishability from background cancers, their rates being proportional to background cancer rates, their rates steadily increasing over at least 50 years as the survivors age, and their radiation dose response being linear. We have successfully described this array of properties with a modified Armitage-Doll model using 5 to 6 somatic mutations, no intermediate growth, and the dose-related replacement of any one of these time-driven mutations by a radiation-induced mutation. Such a model is contrasted to prevailing models that use fewer mutations combined with intervening growth. While the rationale and effectiveness of our model is compelling for carcinogenesis in the atom bomb survivors, the lack of a promotional component may limit the generality of the model for other types of human carcinogenesis.

Mendelsohn, M.L.; Pierce, P.A.

1997-09-04T23:59:59.000Z

405

Introduction and Fundamentals: Course on Advances in Radiation  

E-Print Network (OSTI)

exposure to Ionizing Radiation - is it really necessary?"Sternglass, "Environmental Radiation and Human Health," op.on the Effects of Atomic Radiation Sources and Effects of

Thomas, Ralph H.

2010-01-01T23:59:59.000Z

406

Demonstrating the Potential for First-Class Research in Underdeveloped Countries: Research on Stratospheric Aerosols and Cirrus Clouds Optical Properties, and Radiative Effects in Cuba (1988–2010)  

Science Conference Proceedings (OSTI)

Optical properties of stratospheric aerosols and cirrus clouds and their radiative effects are currently important subjects of research worldwide. Those investigations are typical of developed countries, conducted by several highly specialized groups ...

Juan Carlos Antuña Marrero; René Estevan Arredondo; Boris Barja González

2012-07-01T23:59:59.000Z

407

Defining Top-of-the-Atmosphere Flux Reference Level for Earth Radiation Budget Studies  

Science Conference Proceedings (OSTI)

To estimate the earth's radiation budget at the top of the atmosphere (TOA) from satellite-measured radiances, it is necessary to account for the finite geometry of the earth and recognize that the earth is a solid body surrounded by a ...

Norman G. Loeb; Seiji Kato; Bruce A. Wielicki

2002-11-01T23:59:59.000Z

408

"We will die and become science" : the production of invisibility and public knowledge about Chernobyl radiation effects in Belarus  

E-Print Network (OSTI)

external radiation exposure and internal accumulation ofinternal accumulation), or it might (incorrectly) refer to external radiation exposure.radiation exposure should not be forgotten. Patients, for example, can be checked for their internal

Kuchinskaya, Olga

2007-01-01T23:59:59.000Z

409

The dissipative effect of thermal radiation loss in high-temperature dense plasmas  

E-Print Network (OSTI)

A dynamical model based on the two-fluid dynamical equations with energy generation and loss is obtained and used to investigate the self-generated magnetic fields in high-temperature dense plasmas such as the solar core. The self-generation of magnetic fields might be looked at as a self-organization-type behavior of stochastic thermal radiation fields, as expected for an open dissipative system according to Prigogine's theory of dissipative structures.

L. H. Li; H. Q. Zhang

1997-11-01T23:59:59.000Z

410

Double-diffusive convection with variable viscosity from a vertical truncated cone in porous media in the presence of magnetic field and radiation effects  

Science Conference Proceedings (OSTI)

This work is focused on the study of combined heat and mass transfer or double-diffusive convection near a vertical truncated cone embedded in a fluid-saturated porous medium in the presence of thermal radiation, magnetic field and variable viscosity ... Keywords: Double diffusion, Magnetic field, Porous media, Radiation, Truncated cone, Variable viscosity

A. Mahdy; A. J. Chamkha; Yousef Baba

2010-06-01T23:59:59.000Z

411

EFFECT OF RADIATION ON DYNAMIC PROPERTIES OF HIGH POLYMERS. Progress Report Covering Period July 1, 1957 to June 30, 1958  

SciTech Connect

Progress made during the last year is briefly summarized. Nine additionai technical papers on various aspects of the resesrch work have appeared in print during the last twelve months and these are listed by title and author. A number of additionai polymers were investigated during the year by both dynamnic mechanical techniques and nuclear magnetic resonance techniques. Studies on irradiated polyethylenes were made both for materials subject to Co/ sup 60/ radiation as well as to pile radiation. Apparatus for measuring specific volume from 160 deg K to above the melting point was completed, and a series of branched and irradiated polyethylenes wss investigated. Progress hss also been made in designing and constructing new apparatus for measuremeat of mechanical properties over a frequency range from 1/100 c/s to 20 Mc/s. Dielectric apparatus was assembled and investigations begun, both experimental and theoretical, on determination of the detailed structure of polymer molecules. (auth)

Sauer, J.A.

1958-07-01T23:59:59.000Z

412

Studies on relative effects of charged and neutral defects in hydrogenated amorphous silicon  

DOE Green Energy (OSTI)

This report covers the third year of a continuing research study to understand the relative importance of charged and neutral defects in amorphous silicon. The objective of the study is to explore the electronic structure, including neutral and charged defects, an optoelectronic effects including the formation of Staebler-Wronski defects. The study concentrated on exploring electroluminescence experimentally and interpreting the results employing a simple guiding model. The simple guiding model assumes an exponential density of states and recombination rate constants (radiative and non-radiative) which are governed by hopping transitions. Measurements were also made as a function of photodegradation of the material. The results implicate that the radiative recombination processes are not distant pair tunneling but rather results from electrons hopping down due to the coulomb interactions. Preliminary experiments have been made on the effect of photodegradation on transient space charge limited currents in n/i/n structures. These experiments can directly yield information on the occupied defects centers induced by the photodegradation and are not a result of recombination processes. To date the results seems to be consistent with a picture which places the doubly occupied defects at quite a high energy ({approx equal} 0.4 e.v. below the conduction band).

Silver, M. (North Carolina Univ., Chapel Hill, NC (United States))

1992-02-01T23:59:59.000Z

413

Low Dose Radiation Research Program: William F. Morgan  

NLE Websites -- All DOE Office Websites (Extended Search)

William F. Morgan William F. Morgan Pacific Northwest National Laboratory PO Box 999 Richland, Washington About this Project Projects Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation. Optimizing the Scientific, Regulatory, and Societal Impact of the DOE Low Dose Radiation Research Program A Mechanistic Study of the Radiation Quality Dependence of Bystander Effects in Human Cells. Genetic Factors Affecting Susceptibility to Low-Dose Radiation Mechanisms of Adaptive Responses and Genomic Instability Induced by Low Dose/ Low Dose Rate Radiation Technical Abstracts 2006 Workshop: Using a Low-LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation Sowa, M.B., Goetz, W., Baulch, J., and Morgan, W.F. Genetic Factors Affecting Susceptibility to Low-Dose Radiation

414

Scalable, hydrodynamic and radiation-hydrodynamic studies of neutron stars mergers  

Science Conference Proceedings (OSTI)

We discuss the high performance computing issues involved in the numerical simulation of binary neutron star mergers and supernovae. These phenomena, which are of great interest to astronomers and physicists, can only be described by modeling the gravitational ... Keywords: BiCG, Cray T3E, Silicon Graphics Origin 2000, astronomy, astrophysics, binary neutron stars, eulerian, fluid dynamics, gravitational field, hydrodynamics, iterative methods, linear systems, multidimensions, neutron star, parallel computing, precondition, radiation transport

F. Douglas Swesty; Paul Saylor; Dennis C. Smolarski; E. Y. M. Wang

1997-11-01T23:59:59.000Z

415

Study of collective effects in a low-emittance PEP lattice  

Science Conference Proceedings (OSTI)

This paper summarizes the work on the collective effects studied during the previously described low-emittance operation of PEP. These studies looked at the single bunch and multi-bunch current limits consistent with stable beam operation. The lower than expected current limits and observed coherent beam oscillations, together with methods of countering them, were considered at a recent SSRL workshop. A result of these studies has been that the lower momentum compaction factor and large beta function variations of the low-emittance lattice (a common feature of all proposed high-energy radiation sources) contribute to enhanced collective effects, limiting the early achievable beam intensity to less than the desired 100 mA. The calculational models, especially because of the uncertainty of the beam impedance models, have limited predictability for these effects and will benefit from continued studies of this kind.

Kramer, S.L.; Borland, M.; Galayda, J.; Jackson, A.; Winick, H.; Zisman, M.S. (Argonne National Lab., IL (USA); Stanford Univ., CA (USA). Stanford Synchrotron Radiation Lab.; Brookhaven National Lab., Upton, NY (USA); Lawrence Berkeley Lab., CA (USA); Stanford Univ., CA (USA). Stanford Synchrotron Radiation Lab.; Lawrence Berkeley Lab., CA (USA))

1989-01-01T23:59:59.000Z

416

In-situ Synchrotron Radiation X-ray Scattering Study On The Initial Structure Of Atomic Layer Deposition  

Science Conference Proceedings (OSTI)

Due to the excellent conformality of ALD, it is not only adopted thin film, but also has been adopted for the fabrication of nanostructures. The surface reaction of ALD process is dependent on the substrate condition, thus the study on initial stage of ALD process is crucial to achieve controllable film growth. By the way, because of quite low scattering intensity of initial ultra thin layer, the high flux Synchrotron Radiation is needed. Synchrotron radiation x-ray scattering measurements allow us to investigate the atomic structure evolution of a few nanometer thickness films at the initial growth stage, nondestructively. Ru and TaN ALD films were grown. The thickness, roughness, and electron density were estimated by X-Ray Reflectivity (XRR) analysis. The island structures and its coverage also were estimated.

Park, Y. J. [Pohang Accelerator Laboratory, POSTECH, Pohang, Gyeongbuk (Korea, Republic of); Department of MSE, POSTECH, Pohang, Gyeongbuk (Korea, Republic of); Lee, D. R. [Department of Physics, Soongsil univ., Seoul (Korea, Republic of); Baik, S. [Department of MSE, POSTECH, Pohang, Gyeongbuk (Korea, Republic of)

2011-12-23T23:59:59.000Z

417

Radiation protection at CERN  

E-Print Network (OSTI)

This paper gives a brief overview of the general principles of radiation protection legislation; explains radiological quantities and units, including some basic facts about radioactivity and the biological effects of radiation; and gives an overview of the classification of radiological areas at CERN, radiation fields at high-energy accelerators, and the radiation monitoring system used at CERN. A short section addresses the ALARA approach used at CERN.

Forkel-Wirth, Doris; Silari, Marco; Streit-Bianchi, Marilena; Theis, Christian; Vincke, Heinz; Vincke, Helmut

2013-01-01T23:59:59.000Z

418

International Study of the Sublethal Effects of Fire Smoke on ...  

Science Conference Proceedings (OSTI)

... Study of the Sublethal Effects of Fire Smoke on Survival and Health” (SEFS) to provide scientific information on these effects for public policy makers ...

2002-03-26T23:59:59.000Z

419

Radiation Damage in Nanostructured Metallic Films  

E-Print Network (OSTI)

High energy neutron and charged particle radiation cause microstructural and mechanical degradation in structural metals and alloys, such as phase segregation, void swelling, embrittlement and creep. Radiation induced damages typically limit nuclear materials to a lifetime of about 40 years. Next generation nuclear reactors require materials that can sustain over 60 - 80 years. Therefore it is of great significance to explore new materials with better radiation resistance, to design metals with favorable microstructures and to investigate their response to radiation. The goals of this thesis are to study the radiation responses of several nanostructured metallic thin film systems, including Ag/Ni multilayers, nanotwinned Ag and nanocrystalline Fe. Such systems obtain high volume fraction of boundaries, which are considered sinks to radiation induced defects. From the viewpoint of nanomechanics, it is of interest to investigate the plastic deformation mechanisms of nanostructured films, which typically show strong size dependence. By controlling the feature size (layer thickness, twin spacing and grain size), it is applicable to picture a deformation mechanism map which also provides prerequisite information for subsequent radiation hardening study. And from the viewpoint of radiation effects, it is of interest to explore the fundamentals of radiation response, to examine the microstructural and mechanical variations of irradiated nanometals and to enrich the design database. More importantly, with the assistance of in situ techniques, it is appealing to examine the defect generation, evolution, annihilation, absorption and interaction with internal interfaces (layer interfaces, twin boundaries and grain boundaries). Moreover, well-designed nanostructures can also verify the speculation that radiation induced defect density and hardening show clear size dependence. The focus of this thesis lies in the radiation response of Ag/Ni multilayers and nanotwinned Ag subjected to charged particles. The radiation effects in irradiated nanograined Fe are also investigated for comparison. Radiation responses in these nanostructured metallic films suggest that immiscible incoherent Ag/Ni multilayers are more resistant to radiation in comparison to their monolithic counterparts. Their mechanical properties and radiation response show strong layer thickness dependence in terms of radiation hardening and defect density. Coherent twin boundaries can interact with stacking fault tetrahedral and remove them effectively. Twin boundaries can actively absorb radiation induced defects and defect clusters resulting in boundary migration. Size dependence is also found in nanograins where fewer defects exhibit in films with smaller grains.

Yu, Kaiyuan

2013-05-01T23:59:59.000Z

420

About Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation What is radiation? Radiation is a form of energy that is a part of our everyday lives. All of us receive a "dose" of radiation each day. Most of the dose comes from...

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

THE REACTIONS OF ENERGETIC CARBON ATOMS IN METHANE OXYGEN AND PHASE DEPENDENCE RADIATION DAMAGE EFFECTS  

DOE Green Energy (OSTI)

Studies were made on the reactions of C/sup 11/ in methane containing oxygen. The nuclear reactions C/sup 12/(n,2n) and C/sup 12/(p,pn) were used to produce C/sup 11/. Concomitant radiolysis of the methane during C/sup 11/ production clearly affected product distribution. C/sup 11/-labeled ethane and propane decreased while methane, ethylene, and acetylene decreased. It was assumed that reduction by hydrogen atoms was probably occurring in the unscavenged system. The effects of oxygen and of phase are discussed. In all cases, in duplicate systems, the product distributions resulting from inducing the C/sup 12/(p,pn) reaction were the same within experimental error as those resulting from the C/sup 12/(n,2n) reaction. (P.C.H.)

Stoecklin, G.; Stangl, H.; Christman, D.R.; Cumming, J.B.; Wolf, A.P.

1963-08-01T23:59:59.000Z

422

Assessment of Uncertainty in Cloud Radiative Effects and Heating Rates through Retrieval Algorithm Differences: Analysis using 3-years of ARM data at Darwin, Australia  

SciTech Connect

Ground-based radar and lidar observations obtained at the Department of Energy’s Atmospheric Radiation Measurement Program’s Tropical Western Pacific site located in Darwin, Australia are used to retrieve ice cloud properties in anvil and cirrus clouds. Cloud microphysical properties derived from four different retrieval algorithms (two radar-lidar and two radar only algorithms) are compared by examining mean profiles and probability density functions of effective radius (Re), ice water content (IWC), extinction, ice number concentration, ice crystal fall speed, and vertical air velocity. Retrieval algorithm uncertainty is quantified using radiative flux closure exercises. The effect of uncertainty in retrieved quantities on the cloud radiative effect and radiative heating rates are presented. Our analysis shows that IWC compares well among algorithms, but Re shows significant discrepancies, which is attributed primarily to assumptions of particle shape. Uncertainty in Re and IWC translates into sometimes-large differences in cloud radiative effect (CRE) though the majority of cases have a CRE difference of roughly 10 W m-2 on average. These differences, which we believe are primarily driven by the uncertainty in Re, can cause up to 2 K/day difference in the radiative heating rates between algorithms.

Comstock, Jennifer M.; Protat, Alain; McFarlane, Sally A.; Delanoe, Julien; Deng, Min

2013-05-22T23:59:59.000Z

423

Comparative Study of Different {beta}-Radiation Doses for Preventing Pterygium Recurrence  

SciTech Connect

Purpose: To compare the pterygium recurrence rates after treatment with two different {beta}-radiation doses. Methods and Materials: A total of 84 patients with a mean age of 63.0 {+-} 10.3 years (men, 48 eyes, and women, 47 eyes) and initially treated with {beta}-radiation after pterygium excision were recruited. The mean follow-up period was 49.9 {+-} 51.3 months. The patients were assigned to two dose groups: a high-dose (40 Gy) or a low-dose (20 Gy) group. The statistical significance of differences in pat