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Note: This page contains sample records for the topic "gamma radiation exposure" 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

Effects of gamma radiation on Serratia marcescens; a comparison of effects of two different exposure rates  

E-Print Network [OSTI]

'Donovan, Effect of gamma radiation on Serratia marcescens: Comparison of the radiosensi- tivity of pigmented and nonpigmented cells. Radiation Res, 48, 40-52 (1971). 18. Alison P. Casarett, Radiation ~Biolo . p. 159. Prentice-Hall, Inc. , Englewood Cliffs... EFFECTS OF GAMMA RADIATION ON SL'RNATIA MARCESCENS A COMPARISON OF EFFECTS OF TWO DIFFERENT EXPOSURE RATES A Thesis by CHRISTY ANNETTE MOORE Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirements...

Moore, Christy Annette

1972-01-01T23:59:59.000Z

2

Results of calculations of external gamma radiation exposure rates from fallout and related radionuclide compositions. Operation Teapot, 1955  

SciTech Connect (OSTI)

This report presents data on calculated gamma radiation exposure rates and ground deposition of related radionuclides resulting from events that deposited detectable radioactivity outside the Nevada Test Site complex.

Hicks, H.G.

1981-07-01T23:59:59.000Z

3

Americans' Average Radiation Exposure  

SciTech Connect (OSTI)

We live with radiation every day. We receive radiation exposures from cosmic rays, from outer space, from radon gas, and from other naturally radioactive elements in the earth. This is called natural background radiation. It includes the radiation we get from plants, animals, and from our own bodies. We also are exposed to man-made sources of radiation, including medical and dental treatments, television sets and emission from coal-fired power plants. Generally, radiation exposures from man-made sources are only a fraction of those received from natural sources. One exception is high exposures used by doctors to treat cancer patients. Each year in the United States, the average dose to people from natural and man-made radiation sources is about 360 millirem. A millirem is an extremely tiny amount of energy absorbed by tissues in the body.

NA

2000-08-11T23:59:59.000Z

4

Childhood exposures to Rn-222 and background gamma radiation in the uranium provinces of south Kazakhstan and northern Kyrgyzstan  

Science Journals Connector (OSTI)

The project was undertaken in southern Kazakhstan and Kyrgyzstan. It was speculated that the radiation doses in these areas would be sufficiently high and dispersed to facilitate a case–control study where the radiation doses to leukaemia subjects/their siblings could be compared with those received by control children. As a precursor a pilot project was undertaken to confirm radiation exposures in the region. This was undertaken in association with regional childhood cancer treatment centres. Children from families affected by childhood leukaemia were monitored for 1 month for external ?-radiation dose and for exposure to radon gas. 28 children from families in Kazakhstan and from 31 families in Kyrgyzstan were monitored. The median measured radon in air concentration recorded in Kazakhstan was 123 Bq m?3 and in Kyrgyzstan was 177 Bq m?3. These represent 24-h average indoor/outdoor values. In the case of the ?-doses the mean annual dose was 1.2 mGy for Kazakhstan and 2.1 mGy for Kyrgyzstan. Overall, the results suggest that the populations studied receive similar annual radiation doses to those received by populations living in other areas with enhanced natural radioactivity and that further study of Kazakh and Kyrgyz populations would not facilitate a successful case–control study for childhood leukaemia.

N.D. Priest; D. Hoel; B. Uralbekov; D.O. Baizakova; M. Burkitbayev

2013-01-01T23:59:59.000Z

5

Annual DOE Occupational Radiation Exposure Reports | Department...  

Broader source: Energy.gov (indexed) [DOE]

Annual DOE Occupational Radiation Exposure Reports Annual DOE Occupational Radiation Exposure Reports September 24, 2013 Annual DOE Occupational Radiation Exposure | 2012 Report...

6

Occupational Radiation Exposure | Department of Energy  

Energy Savers [EERE]

Radiation Exposure Welcome The Occupational Radiation Exposure Information page on this web page is intended to provide the latest available information on radiation exposure to...

7

Effects of an acute dose of gamma radiation exposure on stem diameter growth, carbon gain, and biomass partitioning in Helianthus annuus  

SciTech Connect (OSTI)

Nineteen-day-old dwarf sunflower plants (Helianthus annuus, variety NK894) received a variable dose (0-40 Gy) from a cobalt-60 gamma source. A very sensitive stem monitoring device, developed at Battelle's Pacific Northwest Laboratories, Richland, Washington was used to measure real-time changes in stem diameter. Exposure of plants caused a significant reduction in stem growth and root biomass. Doses as low as 5 Gy resulted in a significant increase in leaf density, suggesting that nonreversible morphological growth changes could be induced by very low doses of radiation. Carbohydrate analysis of 40-Gy irradiated plants demonstrated significantly more starch content in leaves and significantly less starch content in stems 18 days after exposure than did control plants. In contrast, the carbohydrate content in roots of 40-Gy irradiated plants were not significantly different from unirradiated plants 18 days after exposure. These results indicate that radiation either decreased phloem transport or reduced the availability of sugar reducing enzymes in irradiated plants. 44 refs., 12 figs.

Thiede, M.E.

1988-05-25T23:59:59.000Z

8

Radiation Exposure Monitoring Systems Data Reporting Guide  

Broader source: Energy.gov [DOE]

Instructions for preparing occupational exposure data for submittal to the Radiation Exposure Monitoring System (REMS) repository.

9

Gamma radiation field intensity meter  

DOE Patents [OSTI]

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

Thacker, L.H.

1995-10-17T23:59:59.000Z

10

Gamma radiation field intensity meter  

DOE Patents [OSTI]

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

Thacker, L.H.

1994-08-16T23:59:59.000Z

11

Gamma radiation field intensity meter  

DOE Patents [OSTI]

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

Thacker, Louis H. (Knoxville, TN)

1995-01-01T23:59:59.000Z

12

Gamma radiation field intensity meter  

DOE Patents [OSTI]

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

Thacker, Louis H. (Knoxville, TN)

1994-01-01T23:59:59.000Z

13

DOE 2013 Occupational Radiation Exposure Report  

Office of Environmental Management (EM)

available on the U.S. Department of Energy Radiation Exposure Monitoring System Program Web Site at: http:energy.govehssoccupational-radiation-exposure Foreword iii MATTHEW B....

14

Annual DOE Occupational Radiation Exposure | 2008 Report  

Broader source: Energy.gov [DOE]

The DOE 2008 Occupational Radiation Exposure Report analyzes occupational radiation exposures at U.S. Department of Energy (DOE) facilities during 2008.

15

ANNUAL DOE OCCUPATIONAL RADIATION EXPOSURE | 2013 REPORT  

Broader source: Energy.gov [DOE]

The DOE 2013 Occupational Radiation Exposure Report analyzes occupational radiation exposures at U.S. Department of Energy (DOE) facilities during 2013.

16

Annual DOE Occupational Radiation Exposure | 2004 Report  

Broader source: Energy.gov [DOE]

The DOE 2004 Occupational Radiation Exposure Report analyzes occupational radiation exposures at U.S. Department of Energy (DOE) facilities during 2004.

17

Annual DOE Occupational Radiation Exposure | 2000 Report  

Broader source: Energy.gov [DOE]

The DOE 2000 Occupational Radiation Exposure Report analyzes occupational radiation exposures at U.S. Department of Energy (DOE) facilities during 2000.

18

Annual DOE Occupational Radiation Exposure | 1999 Report  

Broader source: Energy.gov [DOE]

The DOE Occupational Radiation Exposure Report, 1999 reports occupational radiation exposures incurred by individuals at DOE facilities during the calendar year 1999.

19

Annual DOE Occupational Radiation Exposure | 1974 Report  

Broader source: Energy.gov [DOE]

The Seventh Annual Report of Radiation Exposures for AEC & AEC Contractor Employees analyzes occupational radiation exposures at the Atomic Energy Commission (AEC) and its contractor employees during 1974.

20

Annual DOE Occupational Radiation Exposure | 1997 Report  

Broader source: Energy.gov [DOE]

The DOE Occupational Radiation Exposure Report, 1997 reports occupational radiation exposures incurred by individuals at U.S. Department of Energy (DOE) facilities during the calendar year 1997.

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Annual DOE Occupational Radiation Exposure | 1995 Report  

Broader source: Energy.gov [DOE]

The DOE Occupational Radiation Exposure Report, 1995 reports occupational radiation exposures incurred by individuals at U.S. Department of Energy (DOE) facilities during the calendar year 1995.

22

Annual DOE Occupational Radiation Exposure | 1996 Report  

Broader source: Energy.gov [DOE]

The DOE Occupational Radiation Exposure Report, 1996 reports occupational radiation exposures incurred by individuals at U.S. Department of Energy (DOE) facilities during the calendar year 1996.

23

Annual DOE Occupational Radiation Exposure | 1998 Report  

Broader source: Energy.gov [DOE]

The DOE Occupational Radiation Exposure Report, 1998 reports occupational radiation exposures incurred by individuals at DOE facilities during the calendar year 1998.

24

Annual DOE Occupational Radiation Exposure | 2001 Report  

Broader source: Energy.gov [DOE]

The DOE 2001 Occupational Radiation Exposure Report analyzes occupational radiation exposures at U.S. Department of Energy (DOE) facilities during 2001.

25

Assessing exposure to radiation  

SciTech Connect (OSTI)

Since the founding of Lawrence Livermore National Laboratory, we have been world leaders in evaluating the risks associated with radiation. Ultrasensitive tools allow us not only to measure radionuclides present in the body but also to reconstruct the radiation dose from past nuclear events and to project the levels of radiation that will still be present in the body for 50 years after the initial intake. A variety of laboratory procedures, including some developed here, give us detailed information on the effects of radiation at the cellular level. Even today, we are re-evaluating the neutron dose resulting from the bombing at Hiroshima. Our dose reconstruction and projection capabilities have also been applied to studies of Nagasaki, Chernobyl, the Mayak industrial complex in the former Soviet Union, the Nevada Test Site, Bikini Atoll, and other sites. We are evaluating the information being collected on individuals currently working with radioactive material at Livermore and elsewhere as well as previously collected data on workers that extends back to the Manhattan Project.

Walter, K.

1997-01-01T23:59:59.000Z

26

Annual DOE Occupational Radiation Exposure | 1990 Report  

Broader source: Energy.gov [DOE]

The Twenty-third Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1990.

27

Annual DOE Occupational Radiation Exposure | 1991 Report  

Broader source: Energy.gov [DOE]

The Twenty-fourth Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1991.

28

Annual DOE Occupational Radiation Exposure | 1989 Report  

Broader source: Energy.gov [DOE]

The Twenty-second Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1989.

29

Annual DOE Occupational Radiation Exposure | 1986 Report  

Broader source: Energy.gov [DOE]

The Nineteenth Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1986.

30

Annual DOE Occupational Radiation Exposure | 1982 Report  

Broader source: Energy.gov [DOE]

The Fifteenth Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1982.

31

Annual DOE Occupational Radiation Exposure | 1983 Report  

Broader source: Energy.gov [DOE]

The Sixteenth Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1983.

32

Annual DOE Occupational Radiation Exposure | 1980 Report  

Broader source: Energy.gov [DOE]

The Thirteenth Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1980.

33

Annual DOE Occupational Radiation Exposure | 1979 Report  

Broader source: Energy.gov [DOE]

The Twelfth Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1979.

34

Annual DOE Occupational Radiation Exposure | 1987 Report  

Broader source: Energy.gov [DOE]

The Twentieth Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1987.

35

Annual DOE Occupational Radiation Exposure | 1985 Report  

Broader source: Energy.gov [DOE]

The Eighteenth Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1985.

36

Annual DOE Occupational Radiation Exposure | 1984 Report  

Broader source: Energy.gov [DOE]

The Seventeenth Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1984.

37

Annual DOE Occupational Radiation Exposure | 1981 Report  

Broader source: Energy.gov [DOE]

The Fourteenth Annual Report of Radiation Exposures for DOE & DOE Contractor Employees analyzes occupational radiation exposures at the U.S. Department of Energy (DOE) and its contractor employees during 1981.

38

Radiation Exposure from CT Examinations in Japan  

Science Journals Connector (OSTI)

Computed tomography (CT) is the largest source of medical radiation exposure to the general population, and is ... assess the current situation of CT use in Japan, and to investigate variations in radiation expos...

Yoshito Tsushima; Ayako Taketomi-Takahashi; Hiroyuki Takei…

2010-11-01T23:59:59.000Z

39

INSTRUCTION CONCERNING PRENATAL RADIATION EXPOSURE A. INTRODUCTION  

E-Print Network [OSTI]

/fetus exposed to radiation, a dose limit for the embryo/fetus, and suggestions for reducing radiation exposure and the Radiation Control Officer in writing that she is pregnant and the estimated date of conception.311, FAC, places different radiation dose limits on declared pregnant workers than on adult workers

Slatton, Clint

40

ORISE: DOE's Radiation Exposure Monitoring System (REMS)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Monitoring System (REMS) Monitoring System (REMS) ORISE maintains large database of radition exposure records for the U.S. Department of Energy ORISE staff monitoring radiation data for DOE Rule 10 CFR 835 establishes the U.S. Department of Energy's (DOE) occupational protection rule and requires assessment and recording of radiation doses to individuals who are exposed to sources of radiation or contamination. The Radiation Exposure Monitoring System (REMS) database is the radiation exposure data repository for all monitored DOE employees, contractors, subcontractors and members of the public. REMS maintains dose records for all monitored individuals dating back to 1969. Aggregated, site-specific data are available on the Radiation Exposure Monitoring System website for all years since 1986. Currently,

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Apparatus and method for detecting gamma radiation  

DOE Patents [OSTI]

A high efficiency radiation detector is disclosed for measuring X-ray and gamma radiation from small-volume, low-activity liquid samples with an overall uncertainty better than 0.7% (one sigma SD). The radiation detector includes a hyperpure germanium well detector, a collimator, and a reference source. The well detector monitors gamma radiation emitted by the reference source and a radioactive isotope or isotopes in a sample source. The radiation from the reference source is collimated to avoid attenuation of reference source gamma radiation by the sample. Signals from the well detector are processed and stored, and the stored data is analyzed to determine the radioactive isotope(s) content of the sample. Minor self-attenuation corrections are calculated from chemical composition data. 4 figures.

Sigg, R.A.

1994-12-13T23:59:59.000Z

42

A method for calculation of radiation quantities at all points in gamma radiation calibration fields  

Science Journals Connector (OSTI)

......Chi-square test in a gamma radiation calibration field was...dimensions) in a gamma radiation calibration field can...be used in dosimetry software of gamma radiation calibration fields...2000) Vienna: IAEA. Safety Reports Series, No......

S. M. Hosseini-Pooya; M. Khoshnoodi; A. Ansarinejad; F. Torkzadeh; M. Jafarizadeh

2008-03-01T23:59:59.000Z

43

Reporting Occupational Radiation Exposure Data  

Broader source: Energy.gov [DOE]

IMPORTANT NOTICE: Due to increasing security concerns for the protection of Personnally Identifiable Information (PII), AU-23 has issued a policy statement regarding the submission of radiation...

44

Sources Of Average Individual Radiation Exposure  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Of Average Individual Radiation Exposure Of Average Individual Radiation Exposure Natural background Medical Consumer products Industrial, security, educational and research Occupational 0.311 rem 0.300 rem 0.013 rem 0.0003 rem 0.0005 rem Savannah River Nuclear Solutions, LLC, provides radiological protection services and oversight at the Savannah River Site (SRS). These services include radiation dose measurements for persons who enter areas where they may be exposed to radiation or radioactive material. The results are periodically reported to monitored individuals. The results listed are based on a radiation dose system developed by the International Commission on Radiation Protection. The system uses the terms "effective dose," "equivalent dose" and units of rem. You may be more familiar with the term "millirem" (mrem), which is 1/1000 of a rem.

45

Low dose diagnostic radiation exposure and cancer risk in Trp53+/- mice  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

diagnostic radiation exposure and cancer risk in Trp53+/- mice diagnostic radiation exposure and cancer risk in Trp53+/- mice K Taylor, N Phan, ME Cybulski, L Laframboise, DR Boreham Department of Medical Physics and Applied Radiation Sciences, McMaster University, 1280 Main Street West, Hamilton ON L8S 4K1 The cancer risk associated with exposure to low doses of ionizing radiation has traditionally been extrapolated from effects observed at high doses and high dose rates using a linear no threshold model. Based on this approach, it has been postulated that human exposure to medical imaging involving low doses of x-rays and gamma rays increase an individual's risk of developing cancer throughout their lifetime. Conversely, there is evidence that low doses of gamma radiation increase the latency period of cancer depending upon genotype, cancer type, and the magnitude of

46

Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. I. Test series through HARDTACK II, 1958  

SciTech Connect (OSTI)

In 1959, the Test Manager's Committee to Establish Fallout Doses calculated estimated external gamma exposure at populated locations based upon measurements of external gamma-exposure rate. Using these calculations and estimates of population, we have tabulated the collective estimated external gamma exposures for communities within established fallout patterns. The total collective estimated external gamma exposure is 85,000 person-R. The greatest collective exposures occurred in three general areas: Saint George, Utah; Ely, Nevada; and Las Vegas, Nevada. Three events, HARRY (May 19, 1953), BEE (March 22, 1955), and SMOKY (August 31, 1957), accounted for over half of the total collective estimated external gamma exposure. The bases of the calculational models for external gamma exposure of ''infinite exposure,'' ''estimated exposure,'' and ''one year effective biological exposure'' are explained. 4 figs., 7 tabs.

Anspaugh, L.R.; Church, B.W.

1985-12-01T23:59:59.000Z

47

DOE 2012 Occupational Radiation Exposure October 2013  

SciTech Connect (OSTI)

The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2012 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. Over the past 5-year period, the occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. As an indicator of the overall amount of radiation dose received during the conduct of operations at DOE, the report includes information on collective total effective dose (TED). The TED is comprised of the effective dose (ED) from external sources, which includes neutron and photon radiation, and the internal committed effective dose (CED), which results from the intake of radioactive material into the body. The collective ED from photon exposure decreased by 23% between 2011 and 2012, while the neutron dose increased by 5%. The internal dose components of the collective TED decreased by 7%. Over the past 5-year period, 99.99% of the individuals receiving measurable TED have received doses below the 2 roentgen equivalent in man (rems) (20 millisievert [mSv]) TED administrative control level (ACL), which is well below the DOE regulatory limit of 5 rems (50 mSv) TED annually. The occupational radiation exposure records show that in 2012, DOE facilities continued to comply with DOE dose limits and ACLs and worked to minimize exposure to individuals. The DOE collective TED decreased 17.1% from 2011 to 2012. The collective TED decreased at three of the five sites with the largest collective TED. u Idaho Site – Collective dose reductions were achieved as a result of continuing improvements at the Advanced Mixed Waste Treatment Project (AMWTP) through the planning of drum movements that reduced the number of times a container is handled; placement of waste containers that created highradiation areas in a centralized location; and increased worker awareness of high-dose rate areas. In addition, Idaho had the largest decrease in the total number of workers with measurable TED (1,143 fewer workers). u Hanford Site (Hanford) – An overall reduction of decontamination and decommissioning (D&D) activities at the Plutonium Finishing Plant (PFP) and Transuranic (TRU) retrieval activities resulted in collective dose reductions. u Savannah River Site (SRS) – Reductions were achieved through ALARA initiatives employed site wide. The Solid Waste Management Facility used extended specialty tools, cameras and lead shield walls to facilitate removal of drums. These tools and techniques reduce exposure time through improved efficiency, increase distance from the source of radiation by remote monitoring, shield the workers to lower the dose rate, and reduce the potential for contamination and release of material through repacking of waste. Overall, from 2011 to 2012, there was a 19% decrease in the number of workers with measurable dose. Furthermore, due to a slight decrease in both the DOE workforce (7%) and monitored workers (10%), the ratio of workers with measurable doses to monitored workers decreased to 13%. Another primary indicator of the level of radiation exposure covered in this report is the average measurable dose, which normalizes the collective dose over the population of workers who actually received a measurable dose. The average measurable TED in

none,

2012-02-02T23:59:59.000Z

48

Annual DOE Occupational Radiation Exposure | 1992- 1994 Report  

Broader source: Energy.gov [DOE]

The DOE Occupational Radiation Exposure Report, 1992-1994 reports occupational radiation exposures incurred by individuals at U.S. Department of Energy (DOE) facilities from 1992 through 1994.

49

DOE 2008 Occupational Radiation Exposure October 2009  

SciTech Connect (OSTI)

A major priority of the U.S. Department of Energy (DOE) is to ensure the health, safety, and security of DOE employees, contractors, and subcontractors. The Office of Health, Safety and Security (HSS) provides the corporate-level leadership and strategic vision necessary to better coordinate and integrate health, safety, environment, security, enforcement, and independent oversight programs. One function that supports this mission is the DOE Corporate Operating Experience Program that provides collection, analysis, and dissemination of performance indicators, such as occupational radiation exposure information. This analysis supports corporate decision-making and synthesizes operational information to support continuous environment, safety, and health improvement across the DOE complex.

U.S. Department of Energy, Office of Health, Safety and Security

2009-10-01T23:59:59.000Z

50

DOE 2013 Occupational Radiation Exposure Report ALARA Activities...  

Office of Environmental Management (EM)

disconnection allows termination of correction elements to be conducted in a lower dose rate area and in less time. This innovation will greatly reduce radiation exposures to...

51

A Basic Overview of Occupational Radiation Exposure Monitoring, Analysis & Reporting  

Broader source: Energy.gov [DOE]

This pamphlet is intended to provide a short summary of the Department of Energy Laboratory Accreditation Program and DOE Radiation Exposure Monitoring

52

A Basic Overview of the Occupational Radiation Exposure Monitoring...  

Office of Environmental Management (EM)

and accurate, and conforms to national and international performance and quality assurance standards. The DOE Radiation Exposure Monitoring Systems (REMS) program provides for...

53

Population doses from environmental gamma radiation in Iraq  

SciTech Connect (OSTI)

The exposure rates due to external gamma radiation were measured in 11 Iraqi governerates. Measurements were performed with an Environmental Monitoring System (RSS-111) in open air 1 m above the ground. The average absorbed dose rate in each governerate was as follows (number x 10(-2) microGy h-1): Babylon (6.0), Kerbala (5.3), Al-Najaf (5.4), Al-Kadysia (6.5), Wasit (6.5), Diala (6.5), Al-Anbar (6.5), Al-Muthana (6.6), Maisan (6.8), Thee-Kar (6.6), and Al-Basrah (6.5). The collective doses to the population living in these governerates were 499, 187, 239, 269, 262, 458, 384, 153, 250, 450, and 419 person-Sv, respectively.

Marouf, B.A.; Mohamad, A.S.; Taha, J.S.; al-Haddad, I.K. (Iraq Atomic Energy Commission, Nuclear Research Center, Tuwaitha, Baghdad, (Iraq))

1992-05-01T23:59:59.000Z

54

Assessment of gamma dose rates from terrestrial exposure in Serbia and Montenegro  

Science Journals Connector (OSTI)

......obtained in this study, the radiation hazard was found to be...area. INTRODUCTION Gamma radiation emitted from naturally occuring radioisotopes, such as...Norwegian population from naturally occuring radiation and from Chernobyl fallout......

S. Dragovic; Lj. Jankovic; A. Onjia

2006-12-01T23:59:59.000Z

55

DOE occupational radiation exposure. Report 1992--1994  

SciTech Connect (OSTI)

The DOE Occupational Radiation Exposure Report, 1992-1994 reports occupational radiation exposures incurred by individuals at US Department of Energy (DOE) facilities from 1992 through 1994. This report includes occupational radiation exposure information for all DOE employees, contractors, subcontractors, and visitors. This information is analyzed and trended over time to provide a measure of the DOE`s performance in protecting its workers from radiation. Occupational radiation exposure at DOE has been decreasing over the past 5 years. In particular, doses in the higher dose ranges are decreasing, including the number of doses in excess of the DOE limits and doses in excess of the 2 rem Administrative Control Level (ACL). This is an indication of greater attention being given to protecting these individuals from radiation in the workplace.

NONE

1997-05-01T23:59:59.000Z

56

A Device for Search of Gamma-Radiation Intensive Sources at the Radiation Accident Condition  

SciTech Connect (OSTI)

The procedure designed for measuring angular distributions of gamma radiation and for search of gamma radiation intensive sources is described. It is based on application of the original multidetector device ShD-1, for measuring an angular distribution in a complete solid angle (4 pi). The calibration results and data on the angular distributions of intensity of gamma radiation at the roof of Chornobyl NPP ''Shelter'' are presented.

Batiy, Valeriy; Klyuchnykov, A; Kochnev, N; Rudko, Vladimir; shcherbin, vladimir; Yegorov, V; Schmieman, Eric A.

2005-08-08T23:59:59.000Z

57

ORISE: U.S. Nuclear Regulatory Commission Radiation Exposure Information  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Information and Reporting System (REIRS) Information and Reporting System (REIRS) ORISE maintains large database of radiation exposure records for the U.S. Nuclear Regulatory Commission U.S. Nuclear Regulatory Commission Radiation Exposure Information and Reporting System (REIRS) The U.S. Nuclear Regulatory Commission (NRC) is required by federal mandate to maintain and evaluate radiation protection data for workers at facilities that it licenses. As part of its mission of safety, the NRC operates the Radiation Exposure Information and Reporting System (REIRS), a database system containing all occupational radiation exposure records that have been submitted to the NRC under 10 CFR Part 20. REIRS encompasses 1,800-plus NRC licensees and contains more than five million records for more than one million monitored individuals.

58

Patient radiation exposure during different kyphoplasty techniques  

Science Journals Connector (OSTI)

......could reduce dose and radiation-associated risk...the risk of developing radiation-induced stochastic...specific computer software is available, providing...developed at the Medical Radiation Laboratory of the Finnish...Radiation and Nuclear Safety (STUK)(12). The......

Denis Panizza; Massimo Barbieri; Francesco Parisoli; Luca Moro

2014-01-01T23:59:59.000Z

59

Global methylation responses to low dose radiation exposure  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

methylation responses to low dose radiation exposure methylation responses to low dose radiation exposure Pamela J Sykes, Michelle R Newman, Benjamin J Blyth and Rebecca J Ormsby Haematology and Genetic Pathology, Flinders University and Medical Centre, Flinders Centre for Cancer Prevention and Control, Bedford Park, Adelaide, South Australia 5042 Australia. (pam.sykes@flinders.edu.au). Our goal is to study the mechanisms involved in biological responses to low doses of radiation in vivo in the dose range that is relevant to population and occupational exposures. At high radiation doses, DNA double-strand breaks are considered the critical lesion underlying the initiation of radiation-induced carcinogenesis. However, at the very low radiation doses relevant for the general public, the induction of DNA double-strand breaks

60

Recoilless Nuclear Resonance Absorption of Gamma Radiation  

Science Journals Connector (OSTI)

...GAMMA-RAYS, ARKIV FOR FYSIK 6 : 49 ( 1953...OF GAMMA-RAYS - THEORY AND PRELIMINARY EXPERIMENTS...energy loss. The basic feature of this method...prediction of the theory was that the recoilless...formulation of the theory that the mo-mentum...Malmfors, Arkiv Fysik 6, 49 (1953...

Rudolf L. Mössbauer

1962-09-07T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Operating Experience Level 3, DOE Occupational Radiation Exposures for 2013  

Broader source: Energy.gov [DOE]

This Operating Experience Level 3 (OE-3) document provides an overview summary of radiation doses from occupational exposures at the Department of Energy (DOE), including the National Nuclear Security Administration for the year 2013.

62

Inactivation of aflatoxin B1 by using the synergistic effect of hydrogen peroxide and gamma radiation.  

Science Journals Connector (OSTI)

...peroxide. A 100-krad dose of gamma radiation was sufficient to inactivate...peroxide. A 100-krad dose of gamma radiation was sufficient to inactivate...inhibitors pharmacology radiation effects Animals Dose-Response Relationship...

U D Patel; P Govindarajan; P J Dave

1989-02-01T23:59:59.000Z

63

Molecular signatures of low dose radiation exposure in human subjects  

Science Journals Connector (OSTI)

...Molecular signatures of low dose radiation exposure in human subjects...Volume 46, 2005] 3096 Low dose ionizing radiation (LDIR) in the 1-10 cGy range has largely unknown biological...the effect and risk at low dose by extrapolation from measured...

Zelanna Goldberg; Chad W. Schwietert; Maggie Isbell; Joerg Lehmann; Robin Stern; Christine Hartmann Siantar; and David M. Rocke

2005-05-01T23:59:59.000Z

64

Low Dose Radiation Exposure: Exploring Bystander Effects In Vivo.  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (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

65

Radiation Exposure Monitoring Systems Data Submittal Notification  

Broader source: Energy.gov [DOE]

Monitoring records are required to be reported to the Department of Energy (DOE) Radiation Records Repository by March 31 under DOE Order 231.1B and in accordance with the REMS Reporting Guide.

66

A radiation exposure index for CT  

Science Journals Connector (OSTI)

......metrics provided to operators at the completion of each examination relate to the amount...for each scan, whereas current CTDI indices only quantify the radiation incident...requires manufacturers to generate these indices for clinical examinations. With this......

Walter Huda

2013-12-01T23:59:59.000Z

67

Occupational Radiation Exposures at the Department of Energy  

Broader source: Energy.gov [DOE]

Occupational Radiation Exposures at the Department of Energy Nimi Rao*, U.S. Department of Energy ; Derek Hagemeyer, Oak Ridge Institute for Science and Education Abstract: The DOE Radiation Exposure Monitoring System (REMS) project began in 1969 under the AEC and has undergone significant evolutions since inception. The system serves as the central repository for occupational radiation exposure records for all individuals monitored at DOE facilities. One of the primary purposes of the REMS database is to gather the information needed to produce the annual DOE Occupational Radiation Exposure Report. The report provides analysis of monitoring results over the past 5 years, as well as a historical perspective. The presentation will include the latest information collected for the 2013 monitoring year. Tables and graphics will provide an overview of trends and areas of interest. In addition to the traditional static tables and graphs from the annual report, DOE has initiated a data visualization effort to offer more interactive e-products for the data in REMS. An interactive dashboard tool will be presented, as well as an interactive report on the major impacts on occupational radiation exposure at DOE over the last 10 years.

68

RADIATION EXPOSURE DURING PAEDIATRIC CT IN SUDAN: CT DOSE, ORGAN AND EFFECTIVE DOSES  

Science Journals Connector (OSTI)

......research-article Paper RADIATION EXPOSURE DURING PAEDIATRIC...Energy Commission, Radiation Safety Institute, PO Box 3001...assess the magnitude of radiation exposure during paediatric...CT-Expo 2.1 dosimetry software. Doses were evaluated......

I. I. Suliman; H. M. Khamis; T. H. Ombada; K. Alzimami; M. Alkhorayef; A. Sulieman

2014-11-01T23:59:59.000Z

69

Health Impacts from Acute Radiation Exposure  

SciTech Connect (OSTI)

Absorbed doses above1-2 Gy (100-200 rads) received over a period of a day or less lead to one or another of the acute radiation syndromes. These are the hematopoietic syndrome, the gastrointestinal (GI) syndrome, the cerebrovascular (CV) syndrome, the pulmonary syndrome, or the cutaneous syndrome. The dose that will kill about 50% of the exposed people within 60 days with minimal medical care, LD50-60, is around 4.5 Gy (450 rads) of low-LET radiation measured free in air. The GI syndrome may not be fatal with supportive medical care and growth factors below about 10 Gy (1000 rads), but above this is likely to be fatal. Pulmonary and cutaneous syndromes may or may not be fatal, depending on many factors. The CV syndrome is invariably fatal. Lower acute doses, or protracted doses delivered over days or weeks, may lead to many other health outcomes than death. These include loss of pregnancy, cataract, impaired fertility or temporary or permanent sterility, hair loss, skin ulceration, local tissue necrosis, developmental abnormalities including mental and growth retardation in persons irradiated as children or fetuses, radiation dermatitis, and other symptoms listed in Table 2 on page 12. Children of parents irradiated prior to conception may experience heritable ill-health, that is, genetic changes from their parents. These effects are less strongly expressed than previously thought. Populations irradiated to high doses at high dose rates have increased risk of cancer incidence and mortality, taken as about 10-20% incidence and perhaps 5-10% mortality per sievert of effective dose of any radiation or per gray of whole-body absorbed dose low-LET radiation. Cancer risks for non-uniform irradiation will be less.

Strom, Daniel J.

2003-09-30T23:59:59.000Z

70

LATTICE DYNAMICS NUCLEAR RESONANCE ABSORPTION OF GAMMA-RADIATION  

E-Print Network [OSTI]

crystalline domains are taken. Absorption studies of the dynamics of atomic motions in condensed matterLATTICE DYNAMICS NUCLEAR RESONANCE ABSORPTION OF GAMMA-RADIATION AND COHERENT DECAY MODES Institut Max von Laue-Paul Langevin, Grenoble, France R6sumb. -La section efficace pour l'absorption nucleaire

Paris-Sud XI, Université de

71

E-Print Network 3.0 - acute gamma radiation Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

expressions for the spectral evolution of the early afterglow radiation from gamma-ray bursts... this transition, the radiative efficiency will steadily decrease as ffl ...

72

E-Print Network 3.0 - aux radiations gamma Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

expressions for the spectral evolution of the early afterglow radiation from gamma-ray bursts... this transition, the radiative efficiency will steadily decrease as ffl ...

73

Assessing protection against radiation exposure after prostate 125I brachytherapy  

Science Journals Connector (OSTI)

AbstractPurpose To expand the radiation dose rate measurement data set by measuring radiation under various prostate 125I brachytherapy situations. Methods and Materials Measurements were obtained from 63 consecutive unselected patients at Tokyo Medical Center, Japan. Differences in factors during measurements, such as body postures, distances from the skin surface, and measurement directions were considered. Furthermore, shielding effects of lead-lined underwear, consisting mainly of 0.1-mm thickness of lead, were also assessed. Results Radiation exposure varies according to the patient's body posture, with results differing as much as approximately 40.0% in measured radiation dose rates at 30 cm from the anterior skin surface. Weight, body mass index, and tissue thickness showed good correlations with measured radiation dose rates. The magnitude of radiation exposure attenuation by shielding was approximately 95.8%, similar to the attenuation ratio based on tissue measurements made in the lateral direction. The respective mean times required to reach 1 mSv were 1.2, 7.6, and 65.4 days in the standing position and 0.6, 4.6, and 40.4 days in the supine position at the site of contact, and at 30 and 100 cm from the anterior skin surface. Conclusions This study obtained supplemental information pertaining to radiological protection and confirmed that shielding can be an effective tool for reducing exposures.

Takashi Hanada; Atsunori Yorozu; Riki Kikumura; Toshio Ohashi; Naoyuki Shigematsu

2014-01-01T23:59:59.000Z

74

DOE Radiation Exposure Monitoring System (REMS) Data Update  

SciTech Connect (OSTI)

This slide show presents the 2011 draft data for DOE occupational radiation exposure.Clarification is given on Reporting Data regarding: reporting Total Organ Dose (TOD); reporting Total Skin Dose (TSD), and Total Extremity Dose (TExD) ; and Special individuals reporting.

Rao, Nimi; Hagemeyer, Derek

2012-05-05T23:59:59.000Z

75

Radiation exposure assessment for portsmouth naval shipyard health studies  

Science Journals Connector (OSTI)

......of radiation worker cohorts employed...Hanford Site, Oak Ridge National Laboratory...Canada (AECL) workers from the Chalk...squares) between 1950 and 1996. DISCUSSION...for 13,468 workers with PNS exposure...assignments before and after adjustments......

R. D. Daniels; T. D. Taulbee; P. Chen

2004-09-01T23:59:59.000Z

76

Natural radioactivity and radiation exposure at the Minjingu phosphate mine in Tanzania  

Science Journals Connector (OSTI)

In this paper the results of studies on activity and ambient radiation background around the Minjingu phosphate mine in Tanzania are presented. The outdoor dose rate in air and the activity levels of samples from and outside the mine were determined by thermoluminiscent dosimeters and a gamma spectrometer system with a Hyper Pure germanium detector system respectively. The determination of activity was made for the 226 Ra, 228 Ra, 228 Th and 40 K radionuclides. High concentrations of radium-226 were observed in phosphate rock (5760±107 Bq kg-1 ), waste rock (4250±98 Bq kg-1 ), wild leaf vegetation (650±11 Bq kg-1 ), edible leaf vegetation (393±9 Bq kg-1 ), surface water (4.7±0.4 mBq l-1 ) and chicken feed (4±0.1 Bq kg-1 ) relative to selected control sites. These findings suggest a radiation health risk particularly when the samples are ingested, because the internal exposure may give rise to an effective dose exceeding 20 mSv which is the annual limit of intake of natural radionuclides recommended by the ICRP. On the other hand, the radiation dose from ambient air over five years at the phosphate mine ranges from 1375 to 1475 nGy h-1 with an average of 1415 nGy h-1 . The average is about 28 times that of the global average background radiation from terrestrial sources, and about 12 times the allowed average dose limit for public exposure over five consecutive years. Future investigations on the occupancy factor, external dose rate and radon and radon progeny exposure in drinking water, buildings and activity content in the locally grown foodstuffs are proposed, for the realistic quantification of the overall exposure of workers and public at Minjingu, and remedial measures for future radiation safety.

Firmi P Banzi; Leonard D Kifanga; Felician M Bundala

2000-01-01T23:59:59.000Z

77

E-Print Network 3.0 - atm radiation exposure Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

O'Connell Summary: tissues) 12;Sources of Background Radiation Exposure Naturally occurring radioactive materials... . Cosmic radiation. Fall-out from nuclear weapons...

78

Calicivirus Inactivation by Nonionizing (253.7-Nanometer-Wavelength [UV]) and Ionizing (Gamma) Radiation  

Science Journals Connector (OSTI)

...7-nm-wavelength [UV]) radiation, inactivation by ionizing (gamma) radiation was studied as a process...constituents on inactivation by radiation. MATERIALS AND METHODS Viruses...Shoji Corporation, Tokyo, Japan) was propagated in MDCK...

Ana Maria de Roda Husman; Paul Bijkerk; Willemijn Lodder; Harold van den Berg; Walter Pribil; Alexander Cabaj; Peter Gehringer; Regina Sommer; Erwin Duizer

2004-09-01T23:59:59.000Z

79

Radiation protection in inhomogeneous beta–gamma fields and modelling of hand phantoms with MCNPX  

Science Journals Connector (OSTI)

......performed using the MCNPX software. In order to investigate...recommendations regarding radiation protection measures...Karlsruhe GmbH, Central Safety Department, KES...Simulation Gamma Rays Hand radiation effects Humans Models...radiation effects Software...

Ch. Blunck; F. Becker; L. Hegenbart; B. Heide; J. Schimmelpfeng; M. Urban

2009-02-01T23:59:59.000Z

80

Persistence of gamma-H2AX and 53BP1 foci in proliferating and nonproliferating human mammary epithelial cells after exposure to gamma-rays or iron ions  

SciTech Connect (OSTI)

To investigate {gamma}-H2AX (phosphorylated histone H2AX) and 53BP1 (tumour protein 53 binding protein No. 1) foci formation and removal in proliferating and non-proliferating human mammary epithelial cells (HMEC) after exposure to sparsely and densely ionizing radiation under different cell culture conditions. HMEC cells were grown either as monolayers (2D) or in extracellular matrix to allow the formation of acinar structures in vitro (3D). Foci numbers were quantified by image analysis at various time points after exposure. Our results reveal that in non-proliferating cells under 2D and 3D cell culture conditions, iron-ion induced {gamma}-H2AX foci were still present at 72 h after exposure, although 53BP1 foci returned to control levels at 48 h. In contrast in proliferating HMEC, both {gamma}-H2AX and 53BP1 foci decreased to control levels during the 24-48 h time interval after irradiation under 2D conditions. Foci numbers decreased faster after {gamma}-ray irradiation and returned to control levels by 12 h regardless of marker, cell proliferation status, and cell culture condition. Conclusions: The disappearance of radiation induced {gamma}-H2AX and 53BP1 foci in HMEC have different dynamics that depend on radiation quality and proliferation status. Notably, the general patterns do not depend on the cell culture condition (2D versus 3D). We speculate that the persistent {gamma}-H2AX foci in iron-ion irradiated non-proliferating cells could be due to limited availability of double strand break (DSB) repair pathways in G0/G1-phase, or that repair of complex DSB requires replication or chromatin remodeling.

Groesser, Torsten; Chang, Hang; Fontenay, Gerald; Chen, James; Costes, Sylvain V.; Barcellos-Hoff, Mary Helen; Parvin, Bahram; Rydberg, Bjorn

2010-12-22T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

E-Print Network 3.0 - attenuates gamma radiation Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Astrophysics Research Group Collection: Physics 60 MilagroA TeV Observatory for Gamma Ray Bursts Summary: to gamma rays is likely to complement synchrotron radiation and produce...

82

Directional gamma detector  

DOE Patents [OSTI]

An improved directional gamma radiation detector has a collector sandwiched etween two layers of insulation of varying thicknesses. The collector and insulation layers are contained within an evacuated casing, or emitter, which releases electrons upon exposure to gamma radiation. Delayed electrons and electrons entering the collector at oblique angles are attenuated as they pass through the insulation layers on route to the collector.

LeVert, Francis E. (Downers Grove, Knoxville, TN); Cox, Samson A. (Downers Grove, IL)

1981-01-01T23:59:59.000Z

83

Gravitational radiation from long gamma-ray bursts  

E-Print Network [OSTI]

Long gamma-ray bursts (GRBs) are probably powered by high-angular momentum black hole-torus systems in suspended accretion. The torus will radiate gravitational waves as non-axisymmetric instabilities develop. The luminosity in gravitational-wave emissions is expected to compare favorably with the observed isotropic equivalent luminosity in GRB-afterglow emissions. This predicts that long GRBs are potentially the most powerful LIGO/VIRGO burst-sources in the Universe. Their frequency-dynamics is characterized by a horizontal branch in the $\\dot{f}(f)-$diagram.

Maurice H. P. M. van Putten

2001-02-11T23:59:59.000Z

84

On the Use of SRIM for Computing Radiation Damage Exposure  

SciTech Connect (OSTI)

The SRIM (formerly TRIM) Monte Carlo simulation code is widely used to compute a number of parameters relevant to ion beam implantation and ion beam processing of materials. It also has the capability to compute a common radiation damage exposure unit known as atomic displacements per atom (dpa). Since dpa is a standard measure of primary radiation damage production, most researchers who employ ion beams as a tool for inducing radiation damage in materials use SRIM to determine the dpa associated with their irradiations. The use of SRIM for this purpose has been evaluated and comparisons have been made with an internationally-recognized standard definition of dpa, as well as more detailed atomistic simulations of atomic displacement cascades. Differences between the standard and SRIM-based dpa are discussed and recommendations for future usage of SRIM in radiation damage studies are made. In particular, it is recommended that when direct comparisons between ion and neutron data are intended, the Kinchin-Pease option of SRIM should be selected.

Stoller, Roger E. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Div.; Toloczko, Mychailo B. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Was, Gary S. [Univ. of Michigan, Ann Arbor, MI (United States). Nuclear Engineering and Radiological Sciences; Certain, Alicia G. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Dwaraknath, S. [Univ. of Michigan, Ann Arbor, MI (United States). Nuclear Engineering and Radiological Sciences; Garner, Frank A. [Radiation Effects Consulting, Richland, WA (United States)

2013-06-06T23:59:59.000Z

85

Radiation exposure inside reinforced concrete buildings at Nagasaki  

SciTech Connect (OSTI)

The biological effects on the residents of Hiroshima and Nagasaki due to initial-irradiation exposure during the nuclear attacks of World War II was recognized immediately as an important source of information. After the war, an extensive effort gathered data concerning the locations of individuals at the time of the attack and their subsequent medical histories. The data from personnel located in reinforced concrete buildings are particularly significant, since large groups of occupants received radiation injury without complications due to blast and thermal effects. In order to correlate the radiation dose with physiological effects, the dose to each individual must be calculated. Enough information about the construction of the buildings was available after the war to allow a radiation transport model to be constructed, but the accurate calculation of penetration into such large, thick-walled three dimensional structures was beyond the scope of computing technology until recently. Now, the availability of Cray vector computers and the development of a specially-constructed discrete ordinates transport code, TORT, have combined to allow the successful completion of such a study. This document describes the radiation transport calculations and tabulates the resulting doses by source component and individual case location. An extensive uncertainty analysis is also included. These data are to be used in another study as input to a formal statistical analysis, resulting in a new value for the LD50 dose, i.e., the dose at which the mortality risk is 50%. 55 refs., 67 figs., 70 tabs.

Rhoades, W.A.; Childs, R.L.; Ingersoll, D.T.

1989-05-01T23:59:59.000Z

86

Radiation protection: Natural radiation risks  

Science Journals Connector (OSTI)

... radiation to which humans are exposed consists of four components - cosmic, gamma, internal, radon. The relative contribution that each makes to the sum is shown in the chart. ... but exposure of the whole body to terrestrial gamma rays and of the lungs to radon daughters are influenced by the nature and location of housing. Gamma rays are emitted ...

M. C. O'Riordan

1983-11-17T23:59:59.000Z

87

Polymorphisms in DNA Repair Genes, Medical Exposure to Ionizing Radiation, and Breast Cancer Risk  

Science Journals Connector (OSTI)

...the role of DSB repair in response to low-dose radiation, particularly the range experienced by women from mammograms and other...breast cancer associated with exposure to low doses of ionizing radiation. Although we specifically designed our questionnaire...

Robert C. Millikan; Jon S. Player; Allan Rene deCotret; Chiu-Kit Tse; and Temitope Keku

2005-10-01T23:59:59.000Z

88

rev November 2004 Radiation Safety Manual Section 6 -Personnel Exposure and Monitoring  

E-Print Network [OSTI]

. Estimating Fetal Dose Equivalent .................................................6-10 a. Positionrev November 2004 Radiation Safety Manual Section 6 - Personnel Exposure and Monitoring Page 6-1 Contents .............................................................................6-1 A. Radiation

Wilcock, William

89

Pamphlet, A Basic Overview of Occupational Radiation Exposure Monitoring, Analysis & Reporting  

Broader source: Energy.gov [DOE]

This pamphlet is intended to provide a short summary of two specific HSS programs that aid in the oversight of radiation protection activities at DOE, Department of Energy Laboratory Accreditation Program (DOELAP) and Radiation Exposure Monitoring Systems (REMS)

90

Microbial Community in the Soil Determines the Forest Recovery Post-Exposure to Gamma Irradiation  

Science Journals Connector (OSTI)

High concentrations of radioactive isotopes can find their way into the environment mainly during the storage of high-level radioactive wastes,(1) including spent nuclear reactor fuels generated by nuclear power plants, wastes generated during reprocessing of these fuels, and wastes generated during development of nuclear weapons. ... (5-9) The question of whether microbial populations exposed to ionizing radiation recover in natural environments remains unanswered. ... In the areas where ionizing radiation exposure is likely, such as nuclear reactors or high-level radioactive waste storage sites, it would be valuable to study and archive the radiation sensitive microbial organisms that are essential for proper ecosystem function. ...

Vishal Shah; Shreya Shah; Herman Mackey; Murty Kambhampati; Daniel Collins; Scot E. Dowd; Robert Colichio; Kevin T. McDonnell; Timothy Green

2013-09-25T23:59:59.000Z

91

ON THE KINETIC ENERGY AND RADIATIVE EFFICIENCY OF GAMMA-RAY BURSTS Nicole M. Lloyd-Ronning1  

E-Print Network [OSTI]

ON THE KINETIC ENERGY AND RADIATIVE EFFICIENCY OF GAMMA-RAY BURSTS Nicole M. Lloyd-Ronning1 of 17 gamma-ray bursts (GRBs) during the afterglow phase and ac- counting for radiative losses, we the implications of these results for the GRB radiation and jet models. Subject headinggs: gamma rays: bursts

Zhang, Bing

92

Radiation Exposure in Nonvascular Fluoroscopy-Guided Interventional Procedures  

SciTech Connect (OSTI)

Purpose: To investigate the radiation exposure in non-vascular fluoroscopy guided interventions and to search strategies for dose reduction. Materials and Methods: Dose area product (DAP) of 638 consecutive non-vascular interventional procedures of one year were analyzed with respect to different types of interventions; gastrointestinal tract, biliary interventions, embolizations of tumors and hemorrhage. Data was analyzed with special focus on the fluoroscopy doses and frame doses. The third quartiles (Q3) of fluoroscopy dose values were defined in order to set a reference value for our in-hospital practice. Results: Mean fluoroscopy times of gastrostomy, jejunostomy, right and left sided percutaneous biliary drainage, chemoembolization of the liver and embolization due to various hemorrhages were 5.9, 8.6, 13.5, 16.6, 17.4 and 25.2 min, respectively. The respective Q3 total DAP were 52.9, 73.3, 155.1, 308.4, 428.6 and 529.3 Gy*cm{sup 2}. Overall, around 66% of the total DAP originated from the radiographic frames with only 34% of the total DAP applied by fluoroscopy (P < 0.001). The investigators experience had no significant impact on the total DAP applied, most likely since there was no stratification to intervention-complexity. Conclusion: To establish Diagnostic Reference Levels (DRLs), there is a need to establish a registry of radiation dose data for the most commonly performed procedures. Documentation of interventional procedures by fluoroscopy 'grabbing' has the potential to considerably reduce radiation dose applied and should be used instead of radiographic frames whenever possible.

Kloeckner, Roman, E-mail: kloeckner@radiologie.klinik.uni-mainz.de [Johannes Gutenberg-University, Department of Diagnostic and Interventional Radiology (Germany); Bersch, Anton [Kreuznacher Diakonie, Department of Trauma Surgery and Orthopedics (Germany); Santos, Daniel Pinto dos; Schneider, Jens; Dueber, Christoph; Pitton, Michael Bernhard [Johannes Gutenberg-University, Department of Diagnostic and Interventional Radiology (Germany)

2012-06-15T23:59:59.000Z

93

Comparison of radiation exposure and associated radiation-induced cancer risks from mammography and molecular imaging of the breast  

SciTech Connect (OSTI)

Purpose: Recent studies have raised concerns about exposure to low-dose ionizing radiation from medical imaging procedures. Little has been published regarding the relative exposure and risks associated with breast imaging techniques such as breast specific gamma imaging (BSGI), molecular breast imaging (MBI), or positron emission mammography (PEM). The purpose of this article was to estimate and compare the risks of radiation-induced cancer from mammography and techniques such as PEM, BSGI, and MBI in a screening environment. Methods: The authors used a common scheme for all estimates of cancer incidence and mortality based on the excess absolute risk model from the BEIR VII report. The lifetime attributable risk model was used to estimate the lifetime risk of radiation-induced breast cancer incidence and mortality. All estimates of cancer incidence and mortality were based on a population of 100 000 females followed from birth to age 80 and adjusted for the fraction that survives to various ages between 0 and 80. Assuming annual screening from ages 40 to 80 and from ages 50 to 80, the cumulative cancer incidence and mortality attributed to digital mammography, screen-film mammography, MBI, BSGI, and PEM was calculated. The corresponding cancer incidence and mortality from natural background radiation was calculated as a useful reference. Assuming a 15%-32% reduction in mortality from screening, the benefit/risk ratio for the different imaging modalities was evaluated. Results: Using conventional doses of 925 MBq Tc-99m sestamibi for MBI and BSGI and 370 MBq F-18 FDG for PEM, the cumulative cancer incidence and mortality were found to be 15-30 times higher than digital mammography. The benefit/risk ratio for annual digital mammography was >50:1 for both the 40-80 and 50-80 screening groups, but dropped to 3:1 for the 40-49 age group. If the primary use of MBI, BSGI, and PEM is in women with dense breast tissue, then the administered doses need to be in the range 75-150 MBq for Tc-99m sestamibi and 35 MBq-70 MBq for F-18 FDG in order to obtain benefit/risk ratios comparable to those of mammography in these age groups. These dose ranges should be achievable with enhancements to current technology while maintaining a reasonable examination time. Conclusions: The results of the dose estimates in this study clearly indicate that if molecular imaging techniques are to be of value in screening for breast cancer, then the administered doses need to be substantially reduced to better match the effective doses of mammography.

O'Connor, Michael K.; Li Hua; Rhodes, Deborah J.; Hruska, Carrie B.; Clancy, Conor B.; Vetter, Richard J. [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Department of Medicine, Mayo Clinic, Rochester, Minnesota 55905 (United States); Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Department of Medical Physics, St. James's Hospital, Dublin (Ireland); Radiation Safety, Mayo Clinic, Rochester, Minnesota 55905 (United States)

2010-12-15T23:59:59.000Z

94

MEASUREMENT OF THE HIGH GAMMA RADIATION DOSE USING THE MEMS BASED DOSIMETER AND RADIOLISYS EFFECT  

E-Print Network [OSTI]

radiation dose. If we consider, that the average time of exploitation is estimated to be 40 years and veryMEASUREMENT OF THE HIGH GAMMA RADIATION DOSE USING THE MEMS BASED DOSIMETER AND RADIOLISYS EFFECT M of high and very high doses of ionizing radiation is crucial for the monitoring of the existing Nuclear

Boyer, Edmond

95

Observation of the radiative decay D*+-> D+gamma  

E-Print Network [OSTI]

We have observed a signal for the decay D*(+) --> D(+)gamma at a significance of 4 standard deviations. From the measured branching ratio B(D*(+) --> D(+)gamma)/B(D*(+) --> D(+)pi(0)) = 0.055 +/- 0.014 +/- 0.010 we find B(D*(+) --> D(+)gamma) = 0...

Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Darling, C.; Davis, Robin E. P.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan; Zhou, L.

1998-05-01T23:59:59.000Z

96

APPLICATION OF JITTER RADIATION: GAMMA-RAY BURST PROMPT POLARIZATION  

SciTech Connect (OSTI)

A high degree of polarization of gamma-ray burst (GRB) prompt emission has been confirmed in recent years. In this paper, we apply jitter radiation to study the polarization feature of GRB prompt emission. In our framework, relativistic electrons are accelerated by turbulent acceleration. Random and small-scale magnetic fields are generated by turbulence. We further determine that the polarization property of GRB prompt emission is governed by the configuration of the random and small-scale magnetic fields. A two-dimensional compressed slab, which contains a stochastic magnetic field, is applied in our model. If the jitter condition is satisfied, the electron deflection angle in the magnetic field is very small and the electron trajectory can be treated as a straight line. A high degree of polarization can be achieved when the angle between the line of sight and the slab plane is small. Moreover, micro-emitters with mini-jet structures are considered to be within a bulk GRB jet. The jet 'off-axis' effect is intensely sensitive to the observed polarization degree. We discuss the depolarization effect on GRB prompt emission and afterglow. We also speculate that the rapid variability of GRB prompt polarization may be correlated with the stochastic variability of the turbulent dynamo or the magnetic reconnection of plasmas.

Mao, Jirong [Astrophysical Big Bang Lab, RIKEN, Saitama 351-0198 (Japan); Wang, Jiancheng, E-mail: jirong.mao@riken.jp [Yunnan Observatory, Chinese Academy of Sciences, 650011 Kunming, Yunnan Province (China)

2013-10-10T23:59:59.000Z

97

Alpha Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Basics of Radiation Basics of Radiation Gamma Radiation and X-Rays Beta Radiation Alpha Radiation Irradiation Radioactive Contamination Definitions Detection Measurement Safety Around Radiation Sources Types of Radiation Exposure Managing Radiation Emergencies Basics of Radiation Characteristics of Alpha Radiation 1. Alpha radiation is not able to penetrate skin. 2. Alpha-emitting materials can be harmful to humans if the materials are inhaled, swallowed, or absorbed through open wounds. 3. A variety of instruments have been designed to measure alpha radiation. Special training in use of these instruments is essential for making accurate measurements. 4. A civil defense instrument (CD V-700) cannot detect the presence of radioactive materials that produce alpha radiation unless the radioactive materials also produce beta and/or gamma radiation.

98

E-Print Network 3.0 - activity gamma radiation Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

no. (will be inserted by hand later) Summary: as a function of time. Key words: Gamma ray : bursts -- Shock waves -- ISM : jets and outflous -- Radiation... .10.1; 02.18.5...

99

Detection system for high-resolution gamma radiation spectroscopy with neutron time-of-flight filtering  

DOE Patents [OSTI]

A .gamma.-radiation detection system that includes at least one semiconductor detector such as HPGe-Detector, a position-sensitive .alpha.-Detector, a TOF Controller, and a Digitizer/Integrator. The Digitizer/Integrator starts to process the energy signals of a .gamma.-radiation sent from the HPGe-Detector instantly when the HPGe-Detector detects the .gamma.-radiation. Subsequently, it is determined whether a coincidence exists between the .alpha.-particles and .gamma.-radiation signal, based on a determination of the time-of-flight of neutrons obtained from the .alpha.-Detector and the HPGe-Detector. If it is determined that the time-of-flight falls within a predetermined coincidence window, the Digitizer/Integrator is allowed to continue and complete the energy signal processing. If, however, there is no coincidence, the Digitizer/Integrator is instructed to be clear and reset its operation instantly.

Dioszegi, Istvan; Salwen, Cynthia; Vanier, Peter

2014-12-30T23:59:59.000Z

100

Estimation of external gamma radiation dose in the area of Bory Stobrawskie forests (PL)  

Science Journals Connector (OSTI)

Rather poor relationship between E I and H...was found. The correlation coefficient value was 0.46, supposing existence of other important sources of gamma radiation in environment that were not i...

Agnieszka Do?ha?czuk-?ródka

2012-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Discovering Clinical Biomarkers of Ionizing Radiation Exposure with Serum Proteomic Analysis  

Science Journals Connector (OSTI)

...radiation treatment plans provided serum...long-established gold standard biomarker of radiation...Institutional Review Board-approved...using visual data mining techniques showed...exposure, gold standard lymphocyte assays...through visual data mining activities that...radiation treatment plans provided serum...

Cynthia Ménard; Donald Johann; Mark Lowenthal; Thierry Muanza; Mary Sproull; Sally Ross; James Gulley; Emanuel Petricoin; C. Norman Coleman; Gordon Whiteley; Lance Liotta; and Kevin Camphausen

2006-02-01T23:59:59.000Z

102

Effect of gamma radiation on selected functional and physical properties of liquid egg white  

E-Print Network [OSTI]

had larger air cells with thicker cell walls. The cakes were also tougher and had more resistance to compression. CHAPTER I II EFFECT OF GAMMA RADIATION ON SELECTED PHYSICAL PROPERTIES OF LIqUID EGG WHITE Intr oduct ion As indi. cated in Chapter... EFFECT OF GAMMA RADIATION ON SELECTED FUNCTIONAL AND PHYSICAL PROPERTIES OF LIQUID EGG WHITE A Thesis By Hershell Ray Ball, Jr. Approved as to style and content by) (Chairman of Committee) ead of Department) (Me mba (Member) ( ber) ~Ja...

Ball, Hershell Ray

1966-01-01T23:59:59.000Z

103

Neutron and gamma radiation effects in proton exchanged optical waveguides  

Science Journals Connector (OSTI)

The effect of neutron and gamma ray irradiations on the optical properties of proton exchanged Z-cut lithium niobate optical planar waveguides were investigated. The damage thresholds...

Passaro, Vittorio; Armenise, Mario

2002-01-01T23:59:59.000Z

104

Radiation Exposure to Patient and Staff in Hepatic Chemoembolization: Risk Estimation of Cancer and Deterministic Effects  

Science Journals Connector (OSTI)

In order to calculate the organ doses, we used only the dosemeter values measured ... negligible compared to the direct and significantly longer radiation exposure to the liver region. When one wishes to keep the...

Nico Hidajat; Peter Wust; Roland Felix…

105

E-Print Network 3.0 - accidental radiation exposures Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

many uses, x-rays are the single largest source of man-made radiation exposure. X... -occurring radium and is a major ... Source: Yucca Mountain Project, US EPA Collection:...

106

Modelling of radiation exposure at high altitudes during solar storms  

Science Journals Connector (OSTI)

......with a different energy spectrum. To estimate...exposure due to solar flares, a model...measuring the flux of solar and galactic particles...and the high-energy proton and alpha...Exposure during Solar Maximum) project. One flight from......

H. Al Anid; B. J. Lewis; L. G. I. Bennett; M. Takada

2009-10-01T23:59:59.000Z

107

Exposure assessment: implications for epidemiological studies of ionizing radiation  

Science Journals Connector (OSTI)

......et al. (4) used average doses to birth cohorts...were made in the homes of 58% of the interviewed...histories (e.g. consumption of milk) in order...exposure to radon in homes and lung cancer have...controls on radon in homes are often based on...exposure to high linear energy transfer (LET......

Colin R. Muirhead

2008-12-01T23:59:59.000Z

108

Indoor and Outdoor in Situ High-Resolution Gamma Radiation Measurements in Urban Areas of Cyprus  

E-Print Network [OSTI]

In situ, high-resolution, gamma-ray spectrometry of a total number of 70 outdoor and 20 indoor representative measurements were performed in preselected, common locations of the main urban areas of Cyprus. Specific activities and gamma absorbed dose rates in air due to the naturally occurring radionuclides of Th-232 and U-238 series, and K-40 are determined and discussed. Effective dose rate to the Cyprus population due to terrestrial gamma radiation is derived directly from this work. The results obtained outdoors match very well with those derived previously by high-resolution gamma spectrometry of soil samples, which were collected from the main island bedrock surface. This implies that the construction and building materials in urban areas do not affect the external gamma dose rate; thus they are mostly of local origin. Finally, the indoor/outdoor gamma dose ratio was found to be 1.4 +- 0.5.

E. Svoukis; H. Tsertos

2006-10-02T23:59:59.000Z

109

Effects of combined radiofrequency radiation exposure on levels of reactive oxygen species in neuronal cells  

Science Journals Connector (OSTI)

......typical CDMA signal of 837 MHz and a WCDMA signal of 1950 MHz were applied to the RTL...incubator with a humidified atmosphere of 5% CO2. Analysis...exposure to UMTS 1950 MHz radiation and co-exposure...reaction of menadione with plasma thiols: enhancement......

Kyoung Ah Kang; Hyung Chul Lee; Je-Jung Lee; Mi-Na Hong; Myung-Jin Park; Yun-Sil Lee; Hyung-Do Choi; Nam Kim; Young-Gyu Ko; Jae-Seon Lee

2014-03-01T23:59:59.000Z

110

What is the radiative process of the prompt phase of Gamma Ray Bursts?  

SciTech Connect (OSTI)

Despite the dramatic improvement of our knowledge of the phenomenology of Gamma Ray Bursts, we still do not know several fundamental aspects of their physics. One of the puzzles concerns the nature of the radiative process originating the prompt phase radiation. Although the synchrotron process qualifies itself as a natural candidate, it faces severe problems, and many efforts have been done looking for alternatives. These, however, suffer from other problems, and there is no general consensus yet on a specific radiation mechanism.

Ghisellini, G. [INAF-Osservatorio Astronomico di Brera, Via Bianchi 46 I-23807 Merate (Italy)

2010-07-15T23:59:59.000Z

111

Radon in context of natural radiation exposure: the Czech experience  

Science Journals Connector (OSTI)

......doses from ingestion of water are reasonably avertable...and intervention (remediation of existing exposure...effective dose caused by water containing 1000 Bq l1...radon concentrations in ground water vary from some Becquerel......

J. Hulka

2008-06-01T23:59:59.000Z

112

Influence of relaxation transitions on radiation-initiated cationic graft polymerization. [Gamma radiation  

SciTech Connect (OSTI)

Radiation grafting of vinyl n-butyl ether (VBE) to polyvinyl chloride (PVC) over a broad temperature range was investigated. The relaxation transitions in the PVC/VBE system were also determined. Grafting of vinyl alkyl ethers proceeds entirely by a cationic mechanism in a reaction medium that has been dried to a water concentration no greater than 0.1-1.0 ppm. In this connection, the diffusion properties of water in the temperature region were studied. Commercial films of unplasticized PVC (thickness 200 M); were subjected to swelling in two systems: in a 50% solution of VBE in benzene at 25/sup 0/C, and in the pure monomer at 40/sup 0/C. The reaction mixtures were first dried over metallic sodium in a deaerated atmosphere. The specimens were irradiated in a Co gamma-radiation unit to a dose of 10 kGy at a dose rate of 3 Gy/sec. The first reaction mixture was investigated over a range of temperatures from -60/sup 0/ to +70/sup 0/C, and the second from -15/sup 0/ to +50/sup 0/C. The degree of grafting was determined from the increase in weight of the original ungrafted film. The temperature was held to within +/-1/sup 0/C. The relaxation transitions in the swollen polymer systems were determined by two methods, thermostimulated current (TSC) and thermomechanics (TM). It was found that in the region of the glass transition of a swollen PVC-VBE system, radiation-initiated cationic graft polymerization proceeds at a maximal rate, and there are changes in state of the water molecules (the agents of breaking the ion reaction chain) and in their diffusion properties within the matrix.

Kudryavtsev, V.N.; Kabanov, V.Ya.; Chalykh, A.E.; Spitsyn, V.I.

1982-05-01T23:59:59.000Z

113

Exposure to Low-Dose Ionizing Radiation from Medical Imaging Procedures  

Science Journals Connector (OSTI)

...did not use measures of radiation dose that are specific to the subjects we studied but instead relied on estimates of effective doses, which are neither precisely measured nor subject-specific. The effective dose is a calculated estimate designed to provide a sex-averaged dose for a reference subject... Experimental and epidemiologic evidence has linked exposure to low-dose, ionizing radiation with the development of solid cancers and leukemia.1 As a result, persons at risk for repeated radiation exposure, such as workers in health care and the nuclear ...

Fazel R.; Krumholz H.M.; Wang Y.

2009-08-27T23:59:59.000Z

114

Gamma radiation induced degradation in PE-PP block copolymer  

SciTech Connect (OSTI)

In the present investigation, effect of gamma irradiation on the PP-PE block copolymer has been studied. The polymer has been subjected to gamma irradiation from 100 to 500 Mrad dosages. Characterization of the polymer using XRD and FTIR was done both before irradiation and after irradiation in each step. Effect of irradiation on the electrical properties of the material has also been studied. FTIR study shows that the sample loses C - C stretching mode of vibration but gains C=C stretching mode of vibration after irradiation. Present investigation clearly indicates that though the electrical conductivity increases in the material, it undergoes degradation and shows brittleness due to irradiation.

Ravi, H. R.; Sreepad, H. R.; Ahmed, Khaleel; Govindaiah, T. N. [P.G. Department of Physics, Government College (Autonomous), Mandya - 571401, Karnataka State (India)

2012-06-05T23:59:59.000Z

115

Radiation from Small-Scale Magnetic Field Turbulence: Implications for Gamma-Ray Bursts and Laboratory Astrophysical Plasmas  

E-Print Network [OSTI]

a region of current filamentation, and show that the jitter radiation may be used as a radiative diagnostic to determine features of the magnetic field distribution within this region. For gamma-ray bursts, this instability may play a significant...

Reynolds, Sarah J

2012-05-31T23:59:59.000Z

116

Oligonucleotide microarray analysis of low-dose ionizing radiation exposure  

Science Journals Connector (OSTI)

...health risk due to low-dose ionizing radiation is still debated. Functional...pathways that are induced by ionizing irradiation (IR...transcriptionally regulated by low-dose IR in occupationally...and showed different ranges of accumulated doses...

Paola Silingardi; Elena Morandi; Cinzia Severini; Daniele Quercioli; Monica Vaccari; Wolfango Horn; Maria Concetta Nucci; Vittorio Lodi; Francesco Violante; Sandro Grilli; and Annmaria Colacci

2007-05-01T23:59:59.000Z

117

Radiation and Uranium Resources Exposure Control (South Dakota)  

Broader source: Energy.gov [DOE]

The public policy of South Dakota is to encourage the constructive uses of radiation, the proper development of uranium resources, and the control of any associated harmful effects. The disposal of...

118

Indoor exposure to radiation in the case of an outdoorrelease  

SciTech Connect (OSTI)

This report quantifies the effectiveness of ''sheltering in place'' in a commercial building in the event of an outdoor radiological release. The indoor exposure to airborne particles is calculated by solving the mass balance equation that accounts for the loss of particles due to deposition, filtration and exhaust. Quantitative estimates of shelter-inplace effectiveness are provided for typical commercial buildings.

Price, Phillip N.; Jayaraman, Buvana

2006-06-01T23:59:59.000Z

119

Radiation Exposure From Medical Imaging Time to Regulate?  

E-Print Network [OSTI]

smaller population exposure. The current US situation is that quality control and qual- ity assurance modern medical imaging, there are serious is- sues of quality control, training, and, particularly of different standards and rules are in place; accreditation programs, through the American College

Brenner, David Jonathan

120

Light scattering apparatus and method for determining radiation exposure to plastic detectors  

DOE Patents [OSTI]

An improved system and method of analyzing cumulative radiation exposure registered as pits on track etch foils of radiation dosimeters. The light scattering apparatus and method of the present invention increases the speed of analysis while it also provides the ability to analyze exposure levels beyond that which may be properly measured with conventional techniques. Dosimeters often contain small plastic sheets that register accumulated damage when exposed to a radiation source. When the plastic sheet from the dosimeter is chemically etched, a track etch foil is produced wherein pits or holes are created in the plastic. The number of these pits, or holes, per unit of area (pit density) correspond to the amount of cumulative radiation exposure which is being optically measured by the apparatus. To measure the cumulative radiation exposure of a track etch foil a high intensity collimated beam is passed through foil such that the pits and holes within the track etch foil cause a portion of the impinging light beam to become scattered upon exit. The scattered light is focused with a lens, while the primary collimated light beam (unscattered light) is blocked. The scattered light is focused by the lens onto an optical detector capable of registering the optical power of the scattered light which corresponds to the cumulative radiation to which the track etch foil has been exposed.

Hermes, Robert E. (White Rock, NM)

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Attenuation of VHE Gamma Rays by the Milky Way Interstellar Radiation Field  

SciTech Connect (OSTI)

The attenuation of very high energy gamma rays by pair production on the Galactic interstellar radiation field has long been thought of as negligible. However, a new calculation of the interstellar radiation field consistent with multi-wavelength observations by DIRBE and FIRAS indicates that the energy density of the Galactic interstellar radiation field is higher, particularly in the Galactic center, than previously thought. We have made a calculation of the attenuation of very high energy gamma rays in the Galaxy using this new interstellar radiation field which takes into account its nonuniform spatial and angular distributions. We find that the maximum attenuation occurs around 100 TeV at the level of about 25% for sources located at the Galactic center, and is important for both Galactic and extragalactic sources.

Moskalenko, Igor V.; /Stanford U., HEPL; Porter, Troy A.; /Louisiana State U.; Strong, Andrew W.; /Garching, Max Planck Inst., MPE

2006-04-19T23:59:59.000Z

122

Radiation detection system for portable gamma-ray spectroscopy  

DOE Patents [OSTI]

A portable gamma ray detection apparatus having a gamma ray detector encapsulated by a compact isolation structure having at least two volumetrically-nested enclosures where at least one is a thermal shield. The enclosures are suspension-mounted to each other to successively encapsulate the detector without structural penetrations through the thermal shields. A low power cooler is also provided capable of cooling the detector to cryogenic temperatures without consuming cryogens, due to the heat load reduction by the isolation structure and the reduction in the power requirements of the cooler. The apparatus also includes a lightweight portable power source for supplying power to the apparatus, including to the cooler and the processing means, and reducing the weight of the apparatus to enable handheld operation or toting on a user's person.

Rowland, Mark S. (Alamo, CA); Howard, Douglas E. (Livermore, CA); Wong, James L. (Dublin, CA); Jessup, James L. (Tracy, CA); Bianchini, Greg M. (Livermore, CA); Miller, Wayne O. (Livermore, CA)

2006-06-20T23:59:59.000Z

123

Cumulative exposure to medical sources of ionizing radiation in the first year after pediatric heart transplantation  

Science Journals Connector (OSTI)

Background Pediatric heart transplant recipients undergo a variety of radiologic tests with the attendant risk of exposure to ionizing radiation. We sought to quantify and describe the cumulative exposure to all forms of medical radiation during the first year after pediatric heart transplantation and identify factors associated with higher exposure. Methods Pediatric patients who received a heart transplant between January 2009 and May 2012 with follow-up at our institution were retrospectively reviewed. Patients were included if they survived through 1 year and the first coronary angiography. All medical testing using ionizing radiation performed during follow-up was compiled, and exposures were converted to effective dose (mSv). Results Included were 31 patients who underwent heart transplantation at a median age of 13.6 years (range, 0.3–18.3 years). The median number of radiologic tests performed was 38 (range, 18–154), including 8 catheterizations (range, 2–12), and 28 X-ray images (range, 11–135). Median cumulative effective dose was 53.5 mSv (range, 10.6–153.5 mSv), of which 91% (range, 34%–98%) derived from catheterizations, 31% (range, 8%–89%) of the exposure occurred during the transplant admission, 59% (range, 11%–88%) during planned follow-up, and 3% (0%–56%) during unplanned follow-up. Older age at transplant was a risk factor for increased exposure (p = 0.006). When adjusted for age, a trend toward increased exposure was shown for congenital heart disease as the indication for transplant (p = 0.08), pre-sensitization (p = 0.12), and positive crossmatch (p = 0.09). Conclusions Pediatric heart transplant patients are exposed to significant amounts of ionizing radiation during the first post-transplant year, most during scheduled catheterization. As survival improves, considering the long-term risks associated with these levels of exposure is important.

Alicia McDonnell; Tacy E. Downing; Xiaowei Zhu; Rachel Ryan; Joseph W. Rossano; Andrew C. Glatz

2014-01-01T23:59:59.000Z

124

Microbiological, chemical, and sensory quality changes in Pico de gallo as affected by gamma radiation  

E-Print Network [OSTI]

This study was undertaken to gain a greater understanding of the effects of gamma radiation and storage at 2'C on the microbiological, sensorial and chemical quality of pico de gallo. Samples of pico de gallo were exposed to cobalt'o at a dose of I...

Miller, Gerald Howard

1994-01-01T23:59:59.000Z

125

73Exploring Radiation in your Life Our exposure to many unavoidable sources of radiation is a fact of life, and one  

E-Print Network [OSTI]

and determine the consequences of human radiation impacts, have estimated that the average human accumulates to the daily radiation dose change when the Fukushima source is included in terms of microSeiverts/day? Space73Exploring Radiation in your Life Our exposure to many unavoidable sources of radiation is a fact

126

THE PHOTOSPHERIC RADIATION MODEL FOR THE PROMPT EMISSION OF GAMMA-RAY BURSTS: INTERPRETING FOUR OBSERVED CORRELATIONS  

SciTech Connect (OSTI)

We show that the empirical E{sub p}-L, {Gamma}-L, E{sub p}-{Gamma}, and {eta}-bar{sub {gamma}}-E{sub p} correlations (where L is the time-averaged luminosity of the prompt emission, E{sub p} is the spectral peak energy, {Gamma} is the bulk Lorentz factor, and {eta}-bar{sub {gamma}} is the emission efficiency of gamma-ray bursts, GRBs) are well consistent with the relations between the analogous parameters predicted in the photospheric radiation model of the prompt emission of GRBs. The time-resolved thermal radiation of GRB 090902B does follow the E{sub p}-L and {Gamma}-L correlations. A reliable interpretation of the four correlations in alternative models is still lacking. These may point toward a photospheric origin of prompt emission of some GRBs.

Fan Yizhong; Wei Daming; Zhang Fuwen [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Zhang Binbin, E-mail: yzfan@pmo.ac.cn, E-mail: dmwei@pmo.ac.cn, E-mail: fwzhang@pmo.ac.cn, E-mail: bbzhang@psu.edu [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

2012-08-10T23:59:59.000Z

127

Response of intracerebral human glioblastoma xenografts to multifraction radiation exposures  

SciTech Connect (OSTI)

Purpose: We investigated the effects of fractionated radiation treatments on the life spans of athymic rats bearing intracerebral brain tumors. Methods and Materials: U-251 MG or U-87 MG human glioblastoma cells were implanted into the brains of athymic rats, and the resulting tumors were irradiated once daily with various doses of ionizing radiation for 5 consecutive days or for 10 days with a 2-day break after Day 5. Results: Five daily doses of 1 and 1.5 Gy, and 10 doses of 0.75 and 1 Gy, cured some U-251 MG tumors. However, five daily doses of 0.5 Gy increased the survival time of animals bearing U-251 MG tumors 5 days without curing any animals of their tumors. Ten doses of 0.3 Gy given over 2 weeks extended the lifespan of the host animals 9 days without curing any animals. For U-87 MG tumors, 5 daily doses of 3 Gy produced an increased lifespan of 8 days without curing any animals, and 10 doses of 1 Gy prolonged lifespan 5.5 days without curing any animals. The differences in extension of life span between the 5- and 10-fraction protocols were minor for either tumor type. Conclusion: The finding that the U-251 MG tumors are more sensitive than U-87 MG tumors, despite the fact that U-251 MG tumors contain many more hypoxic cells than U-87 MG tumors, suggests the intrinsic cellular radiosensitivities of these cell lines are more important than hypoxia in determining their in vivo radiosensitivities.

Ozawa, Tomoko [Brain Tumor Research Center, Department of Neurological Surgery, University of California San Francisco, San Francisco, CA (United States); Faddegon, Bruce A. [Department of Radiation Oncology, University of California San Francisco, San Francisco, CA (United States); Hu, Lily J. [Brain Tumor Research Center, Department of Neurological Surgery, University of California San Francisco, San Francisco, CA (United States); Bollen, Andrew W. [Department of Pathology, University of California San Francisco, San Francisco, CA (United States); Lamborn, Kathleen R. [Brain Tumor Research Center, Department of Neurological Surgery, University of California San Francisco, San Francisco, CA (United States); Deen, Dennis F. [Brain Tumor Research Center, Department of Neurological Surgery, University of California San Francisco, San Francisco, CA (United States) and Department of Radiation Oncology, University of California San Francisco, San Francisco, CA (United States)]. E-mail: ddeen@itsa.ucsf.edu

2006-09-01T23:59:59.000Z

128

Occupational Radiation Exposure at Commercial Nuclear Power Reactors and Other Facilities 2008  

SciTech Connect (OSTI)

This report summarizes the occupational exposure data that are maintained in the U.S. Nuclear Regulatory Commission (NRC) Radiation Exposure Information and Reporting System (REIRS). The bulk of the information contained in the report was compiled from the 2008 annual reports submitted by five of the seven categories1 of NRC licensees subject to the reporting requirements of 10 CFR 20.2206. The annual reports submitted by these licensees consist of radiation exposure records for each monitored individual. These records are analyzed for trends and presented in this report in terms of collective dose and the distribution of dose among the monitored individuals. Because there are no geologic repositories for high-level waste currently licensed and no low-level waste disposal facilities in operation, only five categories will be considered in this report.

U.S. Nuclear Regulatory Commission, Office of Nuclear Regulatory Research

2009-12-01T23:59:59.000Z

129

Analysis of radiation exposure, Task Force RAZOR. Exercise Desert Rock VI, Operation Teapot. Technical report  

SciTech Connect (OSTI)

The radiation dose to Task Force RAZOR personnel participating in Shot Apple II of Operation Teapot, Exercise Desert Rock VI, is reconstructed. Task force personnel were exposed to initial radiation while in their vehicles or in trenches at the time of Apple II detonation. They were also exposed to residual radiation during their subsequent manuever and during an inspection of the equipment display area. The calculated total gamma doses to fully-participating Task Force RAZOR personnel range from about 0.8 rem to 1.8 rem. The highest dose was received by personnel of the armored infantry platoon on right flank nearest ground zero. Internal radiation dose commitments to maximally exposed personnel inside vehicles are estimated to be about 0.4 rem to the thyroid, 0.003 rem to the whole body, and 0.002 rem to the bone.

Edwards, R.; Goetz, J.; Klemm, J.

1983-07-15T23:59:59.000Z

130

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

E-Print Network [OSTI]

. 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...

Yuen, Evelyn P

2013-04-19T23:59:59.000Z

131

Assessment of the Technologies for Molecular Biodosimetry for Human Low-Dose Radiation Exposure Symposium  

SciTech Connect (OSTI)

Exposure to ionizing radiation produces few immediate outwardly-visible clinical signs, yet, depending on dose, can severely damage vital physiological functions within days to weeks and produce long-lasting health consequences among survivors. In the event of a radiological accident, the rapid evaluation of the individual absorbed dose is paramount to discriminate the worried but unharmed from those individuals who must receive medical attention. Physical, clinical and biological dosimetry are usually combined for the best dose assessment. However, because of the practical limits of physical and clinical dosimetry, many attempts have been made to develop a dosimetry system based on changes in biological parameters, including techniques for hematology, biochemistry, immunology, cytogenetics, etc. Lymphocyte counts and chromosome aberrations analyses are among the methods that have been routinely used for estimating radiation dose. However, these assays require several days to a week to be completed and therefore cannot be used to obtain a fast estimate of the dose during the first few days after exposure when the information would be most critical for identifying victims of radiation accidents who could benefit the most by medical intervention. The steadily increasing sophistication in our understanding of the early biochemical responses of irradiated cells and tissues provides the opportunity for developing mechanism-based biosignatures of exposure. Compelling breakthroughs have been made in the technologies for genome-scale analysis of cellular transcriptional and proteomic profiles. There have also been major strides in the mechanistic understanding of the early events in DNA damage and radiation damage products, as well as in the cellular pathways that lead to radiation injury. New research with genomic- and proteomic-wide tools is showing that within minutes to hours after exposure to ionizing radiation protein machines are modified and activated, and large-scale changes occur in the gene expression profile involving a broad variety of cell-process pathways after a wide range of both low (<10 cGy) and high dose (>10 cGy) exposures. Evaluation of these potential gene and protein biomarkers for early and late diagnostic information will be critical for determining the efficacy of the signatures to both low and high dose IR exposures. Also needed are approaches that enable rapid handling and processing for mass-casualty and population triage scenarios. Development of in vivo model system will be crucial for validating both the biological and the instrumentation for biodosimetry. Such studies will also help further understanding of the molecular mechanisms of the biological effects of radiation and the differences of responses due to individual genetic variation.

Matthew A. Coleman Ph.D.; Narayani Ramakrishnan, Ph.D.; Sally A. Amundson; James D. Tucker, Ph.D.; Stephen D. Dertinger, Ph.D.; Natalia I. Ossetrova, Ph.D.; Tao Chen

2009-11-16T23:59:59.000Z

132

Comparative investigations of sodium arsenite, arsenic trioxide and cadmium sulphate in combination with gamma-radiation on apoptosis, micronuclei induction and DNA damage in a human lymphoblastoid cell line  

Science Journals Connector (OSTI)

In the field of radiation protection the combined exposure to radiation and other toxic agents is recognised as an important research area. To elucidate the basic mechanisms of simultaneous exposure, the interaction of the carcinogens and environmental toxicants cadmium and two arsenic compounds, arsenite and arsenic trioxide, in combination with gamma-radiation in human lymphoblastoid cells (TK6) were investigated. Gamma-radiation induced significant genotoxic effects such as micronuclei formation, DNA damage and apoptosis, whereas arsenic and cadmium had no significant effect on these indicators of cellular damage at non-toxic concentrations. However, in combination with gamma-radiation arsenic trioxide induced a more than additive apoptotic rate compared to the sum of the single effects. Here, the level of apoptotic cells was increased, in a dose-dependent way, up to two-fold compared to the irradiated control cells. Arsenite did not induce a significant additive effect at any of the concentrations or radiation doses tested. On the other hand, arsenic trioxide was less effective than arsenite in the induction of DNA protein cross-links. These data indicate that the two arsenic compounds interact through different pathways in the cell. Cadmium sulphate, like arsenite, had no significant effect on apoptosis in combination with gamma-radiation at low concentrations and, at high concentrations, even reduced the radiation-induced apoptosis. An additive effect on micronuclei induction was observed with 1 ?M cadmium sulphate with an increase of up to 80% compared to the irradiated control cells. Toxic concentrations of cadmium and arsenic trioxide seemed to reduce micronuclei induction. The results presented here indicate that relatively low concentrations of arsenic and cadmium, close to those occuring in nature, may interfere with radiation effects. Differences in action of the two arsenic compounds were identified.

Sabine Hornhardt; Maria Gomolka; Linda Walsh; Thomas Jung

2006-01-01T23:59:59.000Z

133

PHOTOSPHERIC EMISSION AS THE DOMINANT RADIATION MECHANISM IN LONG-DURATION GAMMA-RAY BURSTS  

SciTech Connect (OSTI)

We present the results of a set of numerical simulations of long-duration gamma-ray burst jets associated with massive, compact stellar progenitors. The simulations extend to large radii and allow us to locate the region in which the peak frequency of the advected radiation is set before the radiation is released at the photosphere. Light curves and spectra are calculated for different viewing angles as well as different progenitor structures and jet properties. We find that the radiation released at the photosphere of matter-dominated jets is able to reproduce the observed Amati and energy-Lorentz factor correlations. Our simulations also predict a correlation between the burst energy and the radiative efficiency of the prompt phase, consistent with observations.

Lazzati, Davide [Department of Physics, NC State University, 2401 Stinson Drive, Raleigh, NC 27695-8202 (United States); Morsony, Brian J. [Department of Astronomy, University of Wisconsin-Madison, 3321 Sterling Hall, 475 N. Charter Street, Madison WI 53706-1582 (United States); Margutti, Raffaella [Harvard-Smithsonian Center for Astrophysics, ITC, 60 Garden Street, Cambridge, MA 02138 (United States); Begelman, Mitchell C. [JILA, University of Colorado and National Institute of Standards and Technology, Boulder, CO 80309-0440 (United States)

2013-03-10T23:59:59.000Z

134

Russian Health Studies Program - Relationship to Other Radiation...  

Office of Environmental Management (EM)

the Mayak workers had long-term exposures (10 to 30 years) to plutonium, gamma, and neutron radiation. This combination of radiation types over a working lifetime is more...

135

Gamma ray bursts may be blueshifted bundles of the relic radiation  

E-Print Network [OSTI]

A hypothesis is proposed that the gamma-ray bursts (GRBs) may arise by blueshifting the emission radiation of hydrogen and helium generated during the last scattering epoch. The blueshift mechanism is provided by such a Lema\\^{\\i}tre -- Tolman (L--T) model, in which the bang-time function $t_B(r)$ is not everywhere constant. Blueshift arises on \\textit{radial} rays that are emitted over regions where $\\dril{t_B} r \

Krasi?ski, Andrzej

2015-01-01T23:59:59.000Z

136

Gamma ray bursts may be blueshifted bundles of the relic radiation  

E-Print Network [OSTI]

A hypothesis is proposed that the gamma-ray bursts (GRBs) may arise by blueshifting the emission radiation of hydrogen and helium generated during the last scattering epoch. The blueshift mechanism is provided by such a Lema\\^{\\i}tre -- Tolman (L--T) model, in which the bang-time function $t_B(r)$ is not everywhere constant. Blueshift arises on \\textit{radial} rays that are emitted over regions where $\\dril{t_B} r \

Andrzej Krasi?ski

2015-02-02T23:59:59.000Z

137

On the Use of SRIM/TRIM for Computing Radiation Damage Exposure  

SciTech Connect (OSTI)

The SRIM (formerly TRIM) Monte Carlo simulation code is widely used to compute a number of parameters relevant to ion beam implantation and ion beam processing of materials. It also has the capability to compute a common radiation damage exposure unit known as atomic displacements per atom (dpa). Since dpa is a standard measure of primary radiation damage production, most researchers who employ ion beams as a tool for inducing radiation damage in materials use SRIM to determine the dpa associated with their irradiations. The use of SRIM for this purpose has been evaluated and comparisons with an internationally-recognized standard definition of dpa, as well as more detailed atomistic simulations of atomic displacement cascades have been made. Differences between the standard and SRIM-based dpa are discussed and recommendations for future usage of SRIM in radiation damage studies are made.

Stoller, Roger E [ORNL; Toloczko, M [Pacific Northwest National Laboratory (PNNL); Was, Gary [University of Michigan; Certain, Alicia [Pacific Northwest National Laboratory (PNNL); Dwaraknath, Shyam [University of Michigan

2013-01-01T23:59:59.000Z

138

Radiation Environments and Exposure Considerations for the Multi?Mission Radioisotope Thermoelectric Generator  

Science Journals Connector (OSTI)

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

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

2006-01-01T23:59:59.000Z

139

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

SciTech Connect (OSTI)

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

Kelly, William M.; Low, Nora M.; Zillmer, Andrew; Johnson, Gregory A. [Pratt and Whitney Rocketdyne, 6633 Canoga Avenue, Canoga Park, CA 91309 (United States); Normand, Eugene [Boeing Radiation Effects Laboratory, P.O. Box 3707, M/S 2T-50, Seattle, WA 98124-22079 (United States)

2006-01-20T23:59:59.000Z

140

Human exposure to high natural background radiation: what can it teach us about  

Science Journals Connector (OSTI)

Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of 222Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case–control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case–control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors.

Jolyon H Hendry; Steven L Simon; Andrzej Wojcik; Mehdi Sohrabi; Werner Burkart; Elisabeth Cardis; Dominique Laurier; Margot Tirmarche; Isamu Hayata

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Mesenchymal Stem Cells Retain Their Defining Stem Cell Characteristics After Exposure to Ionizing Radiation  

SciTech Connect (OSTI)

Purpose: Mesenchymal stem cells (MSCs) have the ability to migrate to lesion sites and undergo differentiation into functional tissues. Although this function may be important for tissue regeneration after radiation therapy, the influence of ionizing radiation (IR) on cellular survival and the functional aspects of differentiation and stem cell characteristics of MSCs have remained largely unknown. Methods and Materials: Radiation sensitivity of human primary MSCs from healthy volunteers and primary human fibroblast cells was examined, and cellular morphology, cell cycle effects, apoptosis, and differentiation potential after exposure to IR were assessed. Stem cell gene expression patterns after exposure to IR were studied using gene arrays. Results: MSCs were not more radiosensitive than human primary fibroblasts, whereas there were considerable differences regarding radiation sensitivity within individual MSCs. Cellular morphology, cytoskeletal architecture, and cell motility were not markedly altered by IR. Even after high radiation doses up to 10 Gy, MSCs maintained their differentiation potential. Compared to primary fibroblast cells, MSCs did not show an increase in irradiation-induced apoptosis. Gene expression analyses revealed an upregulation of various genes involved in DNA damage response and DNA repair, but expression of established MSC surface markers appeared only marginally influenced by IR. Conclusions: These data suggest that human MSCs are not more radiosensitive than differentiated primary fibroblasts. In addition, upon photon irradiation, MSCs were able to retain their defining stem cell characteristics both on a functional level and regarding stem cell marker expression.

Nicolay, Nils H., E-mail: n.nicolay@dkfz.de [Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg (Germany); Department of Molecular and Radiation Oncology, German Cancer Research Center, Heidelberg (Germany); Sommer, Eva; Lopez, Ramon; Wirkner, Ute [Department of Molecular and Radiation Oncology, German Cancer Research Center, Heidelberg (Germany); Trinh, Thuy [Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg (Germany); Department of Molecular and Radiation Oncology, German Cancer Research Center, Heidelberg (Germany); Sisombath, Sonevisay [Department of Molecular and Radiation Oncology, German Cancer Research Center, Heidelberg (Germany); Debus, Jürgen [Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg (Germany); Ho, Anthony D.; Saffrich, Rainer [Department of Hematology and Oncology, Heidelberg University Hospital, Heidelberg (Germany); Huber, Peter E. [Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg (Germany); Department of Molecular and Radiation Oncology, German Cancer Research Center, Heidelberg (Germany)

2013-12-01T23:59:59.000Z

142

Influence of organs in the ICRP's remainder on effective dose equivalent computed for diagnostic radiation exposures  

SciTech Connect (OSTI)

The ICRP effective dose equivalent has been compared with a weighted dose equivalent, computed by treating the entire remainder instead of the sample of five remainder organs in the ICRP method as uniformly radiosensitive, for dose distributions from three common diagnostic exposures: chest, dental full-mouth and dental panoramic. Complete dose distributions were computed by a Monte Carlo model. In all three cases the effective dose equivalent was greater than the weighted dose equivalent. The difference was only 20% for the chest exam but was more than fivefold for both dental exposures. Dose distributions for the dental exposures were less homogeneous than for the chest examination. Selection of organs to be included in the remainder markedly affects the effective dose equivalent. In the case of highly inhomogeneous dose distributions, the effective dose equivalent probably significantly over-estimates radiation detriment.

Gibbs, S.J.

1989-04-01T23:59:59.000Z

143

Uncertainties in estimating health risks associated with exposure to ionising radiation  

Science Journals Connector (OSTI)

The information for the present discussion on the uncertainties associated with estimation of radiation risks and probability of disease causation was assembled for the recently published NCRP Report No. 171 on this topic. This memorandum provides a timely overview of the topic, given that quantitative uncertainty analysis is the state of the art in health risk assessment and given its potential importance to developments in radiation protection. Over the past decade the increasing volume of epidemiology data and the supporting radiobiology findings have aided in the reduction of uncertainty in the risk estimates derived. However, it is equally apparent that there remain significant uncertainties related to dose assessment, low dose and low dose-rate extrapolation approaches (e.g. the selection of an appropriate dose and dose-rate effectiveness factor), the biological effectiveness where considerations of the health effects of high-LET and lower-energy low-LET radiations are required and the transfer of risks from a population for which health effects data are available to one for which such data are not available. The impact of radiation on human health has focused in recent years on cancer, although there has been a decided increase in the data for noncancer effects together with more reliable estimates of the risk following radiation exposure, even at relatively low doses (notably for cataracts and cardiovascular disease). New approaches for the estimation of hereditary risk have been developed with the use of human data whenever feasible, although the current estimates of heritable radiation effects still are based on mouse data because of an absence of effects in human studies. Uncertainties associated with estimation of these different types of health effects are discussed in a qualitative and semi-quantitative manner as appropriate. The way forward would seem to require additional epidemiological studies, especially studies of low dose and low dose-rate occupational and perhaps environmental exposures and for exposures to x rays and high-LET radiations used in medicine. The development of models for more reliably combining the epidemiology data with experimental laboratory animal and cellular data can enhance the overall risk assessment approach by providing biologically refined data to strengthen the estimation of effects at low doses as opposed to the sole use of mathematical models of epidemiological data that are primarily driven by medium/high doses. NASA's approach to radiation protection for astronauts, although a unique occupational group, indicates the possible applicability of estimates of risk and their uncertainty in a broader context for developing recommendations on: (1) dose limits for occupational exposure and exposure of members of the public; (2) criteria to limit exposures of workers and members of the public to radon and its short-lived decay products; and (3) the dosimetric quantity (effective dose) used in radiation protection.

R Julian Preston; John D Boice Jr; A Bertrand Brill; Ranajit Chakraborty; Rory Conolly; F Owen Hoffman; Richard W Hornung; David C Kocher; Charles E Land; Roy E Shore; Gayle E Woloschak

2013-01-01T23:59:59.000Z

144

Operation of {sup 3}He Proportional Chambers in High Gamma Radiation Fields  

SciTech Connect (OSTI)

Operation of {sup 3}He proportional chambers with irradiated fissile materials is limited because of the sensitivity of these chambers to gamma ray events. The optimum performance of these chambers is achieved with proper selection of an additive gas to the chambers and with proper choice of preamplifier and linear amplifier time constants. The counting efficiency of a 4-atm, {sup 3}He-CO2 chamber is improved from 35% to 43% in a 200 R/hr gamma radiation field by decreasing the linear amplifier time constant. Likewise, the counting efficiency of a 1-atm, {sup 3}He-CF4 is improved from 11% to 14% in a 200 R/hr gamma radiation field by decreasing the linear amplifier time constant. The 4-atm, {sup 3}He-CO2 1-in.-OD chamber has a higher efficiency than the 1-atm, {sup 3}He-CF4 1-in.-OD chamber although the energy resolution of the 3 He-CF4 chamber is better than that for the {sup 3}He-CO2 chamber.

Hill, N.W.; Miller, V.C.; Valentine, T.E.; Williams, J.A.

1999-09-01T23:59:59.000Z

145

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

E-Print Network [OSTI]

estimation of the carcinogenic of low-dose, low-LET radiationradiation uoses, close rates, and LET to enable risk tions occur estimation at doses,radiation-induced cancer necessarily be based primarily on human dose-incidence data. in man must However, risk estimation

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

146

Estimation of the radiation exposure of a chest pain protocol with ECG-gating in dual-source computed tomography  

Science Journals Connector (OSTI)

The estimation of the radiation exposure of the protocols we used resulted in effective doses differing among genders: for women, the estimated effective doses were 14.0% higher compared with men...

Dominik Ketelsen; Marie H. Luetkhoff; Christoph Thomas…

2009-01-01T23:59:59.000Z

147

Gamma spectroscopic measurements using the PID350 pixelated CdTe radiation detector  

E-Print Network [OSTI]

Spectroscopic measurements are presented using the PID350 pixelated gamma radiation detectors. A high-speed data acquisition system has been developed in order to reduce the data loss during the data reading in case of a high flux of photons. A data analysis framework has been developed in order to improve the resolution of the acquired energy spectra, using specific calibration parameters for each PID350's pixel. Three PID350 detectors have been used to construct a stacked prototype system and spectroscopic measurements have been performed in order to test the ability of the prototype to localize radioactive sources.

Karafasoulis, K; Seferlis, S; Papadakis, I; Loukas, D; Lambropoulos, C; Potiriadis, C

2010-01-01T23:59:59.000Z

148

Exposure assessment of acrylates/methacrylates in radiation-cured applications  

SciTech Connect (OSTI)

Occupational exposures to radiation-cured acrylates/methacrylates during their processing and use in coatings, inks, and adhesives were evaluated in 12 walk-through surveys at formulator and applicator sites. Inhalation and dermal-exposure routes were studied. According to the authors, the basic process used to formulate coatings, inks, and adhesives consists of blending raw materials in closed mixing vessels using local exhaust ventilation in the form of elephant trunks at vessel charging and packaging locations. Application methods surveyed included reverse-roll coaters, direct roll coaters, curtain/rain coaters, laminators, pneumatic injection, spray guns, and manual application. At the sites surveyed, the number of workers potentially exposed at each site ranged from two to 142. Process operators at applicator sites had the greatest potential for dermal exposure. Generally, the potential for inhalation exposure was low due to low volatility of the multifunctional acrylates/methacrylates used in the formulations. No reliable air-monitoring data were available at any site. Respirator use was limited and sporadic.

Not Available

1987-09-25T23:59:59.000Z

149

PLANNING TOOLS FOR ESTIMATING RADIATION EXPOSURE AT THE NATIONAL IGNITION FACILITY  

SciTech Connect (OSTI)

A set of computational tools was developed to help estimate and minimize potential radiation exposure to workers from material activation in the National Ignition Facility (NIF). AAMI (Automated ALARA-MCNP Interface) provides an efficient, automated mechanism to perform the series of calculations required to create dose rate maps for the entire facility with minimal manual user input. NEET (NIF Exposure Estimation Tool) is a web application that combines the information computed by AAMI with a given shot schedule to compute and display the dose rate maps as a function of time. AAMI and NEET are currently used as work planning tools to determine stay-out times for workers following a given shot or set of shots, and to help in estimating integrated doses associated with performing various maintenance activities inside the target bay. Dose rate maps of the target bay were generated following a low-yield 10{sup 16} D-T shot and will be presented in this paper.

Verbeke, J; Young, M; Brereton, S; Dauffy, L; Hall, J; Hansen, L; Khater, H; Kim, S; Pohl, B; Sitaraman, S

2010-10-22T23:59:59.000Z

150

Human In vivo Dose-Response to Controlled, Low-Dose Low Linear Energy Transfer Ionizing Radiation Exposure  

Science Journals Connector (OSTI)

...biotinylated nucleotide analogue/ribonucleotide mix. The biotinylated cRNA targets were then...dose-response to controlled, low-dose low linear energy transfer ionizing radiation exposure. | The effect of low doses of low-linear energy transfer (photon) ionizing radiation...

Zelanna Goldberg; David M. Rocke; Chad Schwietert; Susanne R. Berglund; Alison Santana; Angela Jones; Jörg Lehmann; Robin Stern; Ruixiao Lu; and Christine Hartmann Siantar

2006-06-15T23:59:59.000Z

151

Analysis of radiation exposure for troop observers, Exercise Desert Rock VI, Operation Teapot. Final report 1 Mar-15 Jul 80  

SciTech Connect (OSTI)

The radiation doses to troop observers and volunteer observers for Exercise Desert Rock VI are reconstructed for each applicable shot of Operation Teapot (1955). Initial neutron and gamma radiation doses are determined from transport codes ATR4 and ATR4.1. Residual radiation contours and decay rates are established through a new automated procedure that utilizes raw data in regression analysis to fit space-time models. Troop operations data are combined with the radiological data to determine integrated dose. Uncertainties are calculated for each parameter. The volunteers received the highest observer--1.6 rem gamma and 4.5 rem neutron. The highest dose received by troop observers was 1.4 rem gamma and 1.4 rem neutron at Shot Tesla.

Goetz, J.; McGahan, J.; Kaul, D.; Weitz, R.; Klemm, J.

1980-07-15T23:59:59.000Z

152

Gamma Radiation Effects on Physical, Optical, and Structural Properties of Binary As-S glasses  

SciTech Connect (OSTI)

Gamma radiation induces changes in physical, optical, and structural properties in chalcogenide glasses., Previous research has focused on As{sub 2}S{sub 3} and families of glasses containing Ge. For the first time, we present composition and dose dependent data on the As-S binary glass series. Binary As{sub x}S{sub 100-x} (x = 30, 33, 36, 40, and 42) glasses were irradiated with gamma radiation using a {sup 60}Co source at 2.8 Gy/s to accumulated doses of 1, 2, 3, and 4 MGy. The irradiated samples were characterized at each dose level for density, refractive index, x-ray diffraction, and Raman spectrum. These results are compared to those of as-made and 1 year aged samples. We report an initial increase in density followed by a decrease as a function of dose that contradicts the expected compositional dependence of molar volume of these glasses. This unusual behavior is explained based on microvoid formation and nanoscale phase-separation induced by the irradiation in these glasses. XRD, Raman, and EPR data provide supporting evidence, underscoring the importance of optimally- or overly-constrained structures for stability under aging or irradiation.

Sundaram, S. K.; McCloy, John S.; Riley, Brian J.; Murphy, Mark K.; Qiao, Hong (Amy) [Amy; Windisch, Charles F.; Walter, Eric D.; Crum, Jarrod V.; Golovchak, Roman; Shpotyuk, O.

2012-03-01T23:59:59.000Z

153

Analysis of radiation exposure, Third Marine Corps Provisional Atomic Exercise Brigade. Exercise Desert Rock VI, Operation Teapot. Technical report  

SciTech Connect (OSTI)

The radiation dose is reconstructed for 3d MCPAEB personnel participating in exercises involving helicopter-lifted assaults in conjunction with Shot Bee of Operation Teapot, Exercise Desert Rock VI. Brigade personnel were exposed to initial radiation while in trenches at the time of the Shot Bee detonation. They were also exposed to residual radiation from an earlier test shot (Shot Turk) during their subsequent maneuvers and to residual radiation from Shot Bee during an inspection of equipment displays. The calculated total gamma doses to the bulk of the participating troops range from about 0.57-0.85 rem.

Goetz, J.; Klemm, J.; Ortlieb, E.

1984-02-15T23:59:59.000Z

154

Radiation Exposures Associated with Shipments of Foreign Research Reactor Spent Nuclear Fuel  

SciTech Connect (OSTI)

Experience has shown that the analyses of marine transport of spent fuel in the Environmental Impact Statement (EIS) were conservative. It is anticipated that for most shipments. The external dose rate for the loaded transportation cask will be more in line with recent shipments. At the radiation levels associated with these shipments, we would not expect any personnel to exceed radiation exposure limits for the public. Package dose rates usually well below the regulatory limits and personnel work practices following ALARA principles are keeping human exposures to minimal levels. However, the potential for Mure shipments with external dose rates closer to the exclusive-use regulatory limit suggests that DOE should continue to provide a means to assure that individual crew members do not receive doses in excess of the public dose limits. As a minimum, the program will monitor cask dose rates and continue to implement administrative procedures that will maintain records of the dose rates associated with each shipment, the vessel used, and the crew list for the vessel. DOE will continue to include a clause in the contract for shipment of the foreign research reactor spent nuclear fuel requiring that the Mitigation Action Plan be followed.

MASSEY,CHARLES D.; MESSICK,C.E.; MUSTIN,T.

1999-11-01T23:59:59.000Z

155

Accelerated alpha-decay of 232U isotope achieved by exposure of its aqueous solution with gold nanoparticles to laser radiation  

E-Print Network [OSTI]

Experimental results are presented on laser-induced accelerated alpha-decay of Uranium-232 nuclei under laser exposure of Au nanoparticles in aqueous solutions of its salt. It is demonstrated that the decrease of alpha-activity strongly depends on the peak intensity of the laser radiation in the liquid and is highest at several terawatt per square centimeter. The decrease of alpha-activity of the exposed solutions is accompanied by the deviation of gamma-activities of daughter nuclides of Uranium-232 from their equilibrium values. Possible mechanisms of the laser influence on the alpha-activity are discussed on the basis of the amplification of the electric field of laser wave on metallic nanoparticles.

A. V. Simakin; G. A. Shafeev

2011-12-29T23:59:59.000Z

156

Polyaniline/poly acid acrylic thin film composites: a new gamma radiation detector  

SciTech Connect (OSTI)

In this paper, we present a new and straightforward route to prepare polyaniline/poly acid acrylic (PAA) thin film composites in large areas and on almost any surface. This method was developed to improve the mechanical and adherence properties of polyaniline devices used as ionization radiation sensors. The route consists of the combination of the metal oxidant with polymer acid to form a highly homogeneous and viscous paste, which can be easily spread over any surface. In the second step, an aniline acid solution is brought in contact with the dried paste where polymerization occurs, yielding a high homogeneous and conducting polymer composite. The UV-visible absorption and infrared analysis confirm that a polyaniline/PAA complex is obtained. The four-point conductivity measurements show that the composite conductivity {rho} is the order of 5 {omega}{sup -1} cm{sup -1}. Preliminary gamma radiation interaction with the composite shows that the doped composite exhibits a linear response that can be used in the development of real-time radiation sensors for the dose range from 0 to 5000 Gy.

Lima Pacheco, Ana P.; Araujo, Elmo S.; Azevedo, Walter M. de

2003-03-15T23:59:59.000Z

157

Very High Energy Gamma Rays from Supernova Remnants and Constraints on the Galactic Interstellar Radiation Field  

SciTech Connect (OSTI)

The large-scale Galactic interstellar radiation field (ISRF) is the result of stellar emission and dust re-processing of starlight. Where the energy density of the ISRF is high (e.g., the Galactic Centre), the dominant {gamma}-ray emission in individual supernova remnants (SNRs), such as G0.9+0.1, may come from inverse Compton (IC) scattering of the ISRF. Several models of the ISRF exist. The most recent one, which has been calculated by us, predicts a significantly higher ISRF than the well used model of Mathis, Mezger, and Panagia [1]. However, comparison with data is limited to local observations. Based on our current estimate of the ISRF we predict the gamma-ray emission in the SNRs G0.9+0.1 and RXJ1713, and pair-production absorption features above 20 TeV in the spectra of G0.9+0.1, J1713-381, and J1634-472. We discuss how GLAST, along with current and future very high energy instruments, may be able to provide upper bounds on the large-scale ISRF.

Porter, T.A.; Moskalenko, I.V.; Strong, A.W.

2007-04-30T23:59:59.000Z

158

Very High Energy Gamma Rays from Supernova Remnants and Constraints on the Galactic Interstellar Radiation Field  

E-Print Network [OSTI]

The large-scale Galactic interstellar radiation field (ISRF) is the result of stellar emission and dust re-processing of starlight. Where the energy density of the ISRF is high (e.g., the Galactic Centre), the dominant gamma-ray emission in individual supernova remnants (SNRs), such as G0.9+0.1, may come from inverse Compton (IC) scattering of the ISRF. Several models of the ISRF exist. The most recent one, which has been calculated by us, predicts a significantly higher ISRF than the well-used model of Mathis, Mezger, and Panagia. However,comparison with data is limited to local observations. Based on our current estimate of the ISRF we predict the gamma-ray emission in the SNRs G0.9+0.1 and RXJ1713, and pair-production absorption features above 20 TeV in the spectra of G0.9+0.1, J1713-381, and J1634-472. We discuss how GLAST, along with current and future very high energy instruments, may be able to provide upper bounds on the large-scale ISRF.

Porter, T A; Strong, A W

2007-01-01T23:59:59.000Z

159

Very High Energy Gamma Rays from Supernova Remnants and Constraints on the Galactic Interstellar Radiation Field  

E-Print Network [OSTI]

The large-scale Galactic interstellar radiation field (ISRF) is the result of stellar emission and dust re-processing of starlight. Where the energy density of the ISRF is high (e.g., the Galactic Centre), the dominant gamma-ray emission in individual supernova remnants (SNRs), such as G0.9+0.1, may come from inverse Compton (IC) scattering of the ISRF. Several models of the ISRF exist. The most recent one, which has been calculated by us, predicts a significantly higher ISRF than the well-used model of Mathis, Mezger, and Panagia. However,comparison with data is limited to local observations. Based on our current estimate of the ISRF we predict the gamma-ray emission in the SNRs G0.9+0.1 and RXJ1713, and pair-production absorption features above 20 TeV in the spectra of G0.9+0.1, J1713-381, and J1634-472. We discuss how GLAST, along with current and future very high energy instruments, may be able to provide upper bounds on the large-scale ISRF.

T. A. Porter; I. V. Moskalenko; A. W. Strong

2007-04-13T23:59:59.000Z

160

FY06 Annual Report: Amorphous Semiconductors for Gamma Radiation Detection (ASGRAD)  

SciTech Connect (OSTI)

We describe progress in the development of new materials for portable, room-temperature, gamma-radiation detection at Pacific Northwest National Laboratory at the Hanford Site in Washington State. High Z, high resistivity, amorphous semiconductors are being designed for use as solid-state detectors at near ambient temperatures; principles of operation are analogous to single-crystal semiconducting detectors. Amorphous semiconductors have both advantages and disadvantages compared to single crystals, and this project is developing methods to mitigate technical problems and design optimized material for gamma detection. Several issues involved in the fabrication of amorphous semiconductors are described, including reaction thermodynamics and kinetics, the development of pyrolytic coating, and the synthesis of ingots. The characterization of amorphous semiconductors is described, including sectioning and polishing protocols, optical microscopy, X-ray diffraction, scanning electron microscopy, optical spectroscopy, particle-induced X-ram emission, Rutherford backscattering, and electrical testing. Then collaboration with the University of Illinois at Urbana-Champaign is discussed in the areas of Hall-effect measurements and current voltage data. Finally, we discuss the strategy for continuing the program.

Johnson, Bradley R.; Riley, Brian J.; Crum, Jarrod V.; Sundaram, S. K.; Henager, Charles H.; Zhang, Yanwen; Shutthanandan, V.

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Lesson 4 - Ionizing Radiation | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

4 - Ionizing Radiation 4 - Ionizing Radiation Lesson 4 - Ionizing Radiation Lesson Three showed that unstable isotopes emit energy as they become more stable. This energy is known as radiation. This lesson explores forms of radiation, where radiation is found, how we detect and measure radiation, what sources of radiation people are exposed to, whether radiation is harmful, and how we can limit our exposure. Specific topics covered in this lesson include: Types of radiation Non-ionizing Ionizing Forms of ionizing radiation Alpha particles Beta particles Gamma rays Radiation Decay chain Half-life Dose Radiation measurements Sources of radiation Average annual exposure Lesson 4 - Ionizing Radiation.pptx More Documents & Publications DOE-HDBK-1130-2008 DOE-HDBK-1130-2008 DOE-HDBK-1130-2007

162

Analysis of Gamma Radiation from a Radon Source: Indications of a Solar Influence  

E-Print Network [OSTI]

This article presents an analysis of about 29,000 measurements of gamma radiation associated with the decay of radon in a sealed container at the Geological Survey of Israel (GSI) Laboratory in Jerusalem between 28 January 2007 and 10 May 2010. These measurements exhibit strong variations in time of year and time of day, which may be due in part to environmental influences. However, time-series analysis reveals a number of periodicities, including two at approximately 11.2 year$^{-1}$ and 12.5 year$^{-1}$. We have previously found these oscillations in nuclear-decay data acquired at the Brookhaven National Laboratory (BNL) and at the Physikalisch-Technische Bundesanstalt (PTB), and we have suggested that these oscillations are attributable to some form of solar radiation that has its origin in the deep solar interior. A curious property of the GSI data is that the annual oscillation is much stronger in daytime data than in nighttime data, but the opposite is true for all other oscillations. This may be a systematic effect but, if it is not, this property should help narrow the theoretical options for the mechanism responsible for decay-rate variability.

Peter A. Sturrock; Gideon Steinitz; Ephraim Fischbach; Daniel Javorsek, II; Jere H. Jenkins

2012-05-01T23:59:59.000Z

163

Radiation exposure and central nervous system cancers: A case-control study among workers at two nuclear facilities  

SciTech Connect (OSTI)

A nested case-control study was conducted among workers employed between 1943 and 1977 at two nuclear facilities to investigate the possible association of primary malignant neoplasms of the central nervous system (CNS) with occupational exposure to ionizing radiation from external and internal sources. Eighty-nine white male and female workers, who according to the information on death certificates dies of primary CNS cancers, were identified as cases. Four matched controls were selected for each case. External radiation exposure data were available from film badge readings for individual workers, whereas radiation dose to lung from internally deposited radionuclides, mainly uranium, was estimated from area and personnel monitoring data and was used in analyses in lieu of the dose to the brain. Matched sets were included in the analyses only if information was available for the case and at least one of the corresponding controls. Thus, the analyses of external radiation included 27 cases and 90 matched controls, and 47 cases and 120 matched controls were analyzed for the effects of radiation from internally deposited uranium. No association was observed between deaths fron CNS cancers and occupational exposure to ionizing radiation from external or internal sources. However, due to the small number of monitored subjects and low doses, a weak association could not be ruled out. 43 refs., 1 fig., 15 tabs.

Carpenter, A.V.; Flanders, W.D.; Frome, E.L.; Crawford-Brown, D.J.; Fry, S.A.

1987-03-01T23:59:59.000Z

164

Analysis of radiation exposure for naval units of Operation CROSSROADS. Volume 1. Basic report. Technical report  

SciTech Connect (OSTI)

External radiation doses are reconstructed for crews of support and target ships of Joint Task Force One at Operation CROSSROADS, 1946. Volume I describes the reconstruction methodology, which consists of modeling the radiation environment, to include the radioactivity of lagoon water, target ships, and support ship contamination; retracing ship paths through this environment; and calculating the doses to shipboard personnel. The USS RECLAIMER, a support ship, is selected as a representative ship to demonstrate this methodology. Doses for all other ships are summarized. Volume II (Appendix A) details the results for target ship personnel. Volume III (Appendix B) details the results for support ship personnel. Calculated doses for more than 36,000 personnel aboard support ships while at Bikini range from zero to 1.7 rem. Of those approximately 34,000 are less than 0.5 rem. From the models provided, doses due to target ship reboarding and doses accrued after departure from Bikini can be calculated, based on the individual circumstances of exposure.

Weitz, R.; Thomas, C.; Klemm, J.; Stuart, J.; Knowles, M.

1982-03-03T23:59:59.000Z

165

Natural radioactivity and external gamma radiation exposure at the coastal Red Sea in Egypt  

Science Journals Connector (OSTI)

......0.5 - 151 39 1.08 0.27 - (25) Sudan 29.6 6.02 158.4 4.09...Natural radioactivity in sand used in thermal therapy at the Red Sea Coast. J. Environ...in the Red Sea coastal environment of Sudan. Mar. Pollut. Bull. (1998) 36......

S. Harb

2008-07-01T23:59:59.000Z

166

Assessment of radiation exposure for materials in the LANSCE Spallation Irradiation Facility  

SciTech Connect (OSTI)

Materials samples were irradiated in the Los Alamos Radiation Effects Facility (LASREF) at the Los Alamos Neutron Science Center (LANSCE) to provide data for the Accelerator Production of Tritium (APT) project on the changes in mechanical and physical properties of materials in a spallation target environment. The targets were configured to expose samples to a variety of radiation environments including high-energy protons, mixed protons and neutrons, and predominantly neutrons. The irradiation was driven by an 800 MeV 1 mA proton beam with a circular Gaussian shape of approximately 2{sigma} = 3.5 cm. Two irradiation campaigns were conducted in which samples were exposed for approximately six months and two months, respectively. At the end of this period, the samples were extracted and tested. Activation foils that had been placed in proximity to the materials samples were used to quantify the fluences in various locations. The STAYSL2 code was used to estimate the fluences by combining the activation foil data with calculated data from the LAHET Code System (LCS) and MCNPX. The exposure for each sample was determined from the estimated fluences using interpolation based on a mathematical fitting to the fluence results. The final results included displacement damage (dpa) and gas (H, He) production for each sample from the irradiation. Based on the activation foil analysis, samples from several locations in both irradiation campaigns were characterized. The radiation damage to each sample was highly dependent upon location and varied from 0.023 to 13 dpa and was accompanied by high levels of H and He production.

James, M. R. (Michael R.); Maloy, S. A. (Stuart A.); Sommer, W. F. (Walter F.), Jr.; Fowler, Malcolm M.; Dry, D. E. (Donald E.); Ferguson, P. D. (Phillip D.); Corzine, R. K. (R. Karen); Mueller, G. E. (Gary E.)

2001-01-01T23:59:59.000Z

167

The influence of {gamma}-ray radiation on electrical properties of CuGaSe{sub 2}  

SciTech Connect (OSTI)

The effect of {gamma}-ray radiation on the conductivity of low-resistivity (10{sup 2}2-10{sup 4} {Omega} cm) and high-resistivity (10{sup 5}-10{sup 7} {Omega} cm) CuGaSe{sub 2} single crystals has been studied in the temperature range 77-330 K. It is found that the resistivity of low-resistivity samples increases as the dose of {gamma}-ray radiation is increased, while the resistivity of high-resistivity samples is practically independent of the radiation dose. It is assumed that a decrease in the conductivity of the low-resistivity samples occurs owing to scattering of free charge carriers at defects (charged centers) formed as a result of irradiation with {gamma}-ray photons. It is found that the dose of the {gamma}-ray irradiation does not affect the temperature dependence of resistivity in the low- and high-resistivity samples in the temperature range 77-300 K.

Kasumoglu, I.; Kerimova, T. G., E-mail: ktaira@physics.ab.az; Mamedova, I. A. [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan)

2011-01-15T23:59:59.000Z

168

How radiation exposure affects immunogenetical risk of stomach cancer among atomic-bomb survivors  

Science Journals Connector (OSTI)

...Targeted alpha-Particle Radiation Therapy Kwamena E. Baidoo...comparison of the structure of radiation oncology in the United States and Japan.Int J Radiat Oncol Biol...FAQs/Fast-Facts-About-Radiation-Therapy/Index.aspx...

Tomonori Hayashi; Kazue Imai; Yoichiro Kusunoki; Kei Nakachi; and Eiichi Tahara

2005-05-01T23:59:59.000Z

169

Radiation exposure for 'caregivers' during high-dose outpatient radioiodine therapy  

Science Journals Connector (OSTI)

......designed to evaluate radiation safety issues and predict...to comply with radiation safety instructions...list of radiation safety instructions...record cumulative radiation dose for each...using EasyEPD2 software (version 1......

Christopher J. Marriott; Colin E. Webber; Karen Y. Gulenchyn

2007-01-01T23:59:59.000Z

170

Assessment of the occupational radiation exposure doses to workers at INMOL Pakistan (2007–11)  

Science Journals Connector (OSTI)

......measures and safety of workers during...been sent to the Radiation Dosimetry Laboratory...fabricated computer software . The calibration...PNRA and IAEA radiation protection and safety guidelines...radiation and for the safety of radiation sources. (1994......

Khalid Masood; Junaid Zafar; Tasneem Zafar; Haroon Zafar

2013-06-01T23:59:59.000Z

171

Study of anticipated impact on DOE programs from proposed reductions to the external occupational radiation exposure limit  

SciTech Connect (OSTI)

A study of the impact of reducing the occupational radiation exposure limit from 5 rem/yr to 2.5, 1.0 and 0.5 rem/yr, respectively produced the following conclusions: reduction of the occupational exposure limit would result in significant increase in total accumulated exposure to the current radiation worker population and could require an increase in the work force; important programs would have to be abandoned at a planned exposure limit of 0.5 rem/yr; some engineering technology is not sufficiently developed to design or operate at the 0.5 rem/yr limit; even a factor of 2 reduction (2.5 rem/yr) would significantly increase costs and would result in an increase in total exposure to the work force; in addition to a significant one-time initial capital cost resulting from a 0.5 rem/yr limit, there would be a significant increase in annual costs; the major emphasis in controlling occupational exposure should be on further reduction of total man-rem; and current standards are used only as a limit. For example, 97% of the employees receive less than 0.5 rem/yr.

None

1981-02-01T23:59:59.000Z

172

Detection of embedded radiation sources using temporal variation of gamma spectral data.  

SciTech Connect (OSTI)

Conventional full spectrum gamma spectroscopic analysis has the objective of quantitative identification of all the isotopes present in a measurement. For low energy resolution detectors, when photopeaks alone are not sufficient for complete isotopic identification, such analysis requires template spectra for all the isotopes present in the measurement. When many isotopes are present it is difficult to make the correct identification and this process often requires many trial solutions by highly skilled spectroscopists. This report investigates the potential of a new analysis method which uses spatial/temporal information from multiple low energy resolution measurements to test the hypothesis of the presence of a target spectrum of interest in these measurements without the need to identify all the other isotopes present. This method is referred to as targeted principal component analysis (TPCA). For radiation portal monitor applications, multiple measurements of gamma spectra are taken at equally spaced time increments as a vehicle passes through the portal and the TPCA method is directly applicable to this type of measurement. In this report we describe the method and investigate its application to the problem of detection of a radioactive localized source that is embedded in a distributed source in the presence of an ambient background. Examples using simulated spectral measurements indicate that this method works very well and has the potential for automated analysis for RPM applications. This method is also expected to work well for isotopic detection in the presence of spectrally and spatially varying backgrounds as a result of vehicle-induced background suppression. Further work is needed to include effects of shielding, to understand detection limits, setting of thresholds, and to estimate false positive probability.

Shokair, Isaac R.

2011-09-01T23:59:59.000Z

173

GAMMA RADIATION INTERACTS WITH MELANIN TO ALTER ITS OXIDATION-REDUCTION POTENTIAL AND RESULTS IN ELECTRIC CURRENT PRODUCTION  

SciTech Connect (OSTI)

The presence of melanin pigments in organisms is implicated in radioprotection and in some cases, enhanced growth in the presence of high levels of ionizing radiation. An understanding of this phenomenon will be useful in the design of radioprotective materials. However, the protective mechanism of microbial melanin in ionizing radiation fields has not yet been elucidated. Here we demonstrate through the electrochemical techniques of chronoamperometry, chronopotentiometry and cyclic voltammetry that microbial melanin is continuously oxidized in the presence of gamma radiation. Our findings establish that ionizing radiation interacts with melanin to alter its oxidation-reduction potential. Sustained oxidation resulted in electric current production and was most pronounced in the presence of a reductant, which extended the redox cycling capacity of melanin. This work is the first to establish that gamma radiation alters the oxidation-reduction behavior of melanin, resulting in electric current production. The significance of the work is that it provides the first step in understanding the initial interactions between melanin and ionizing radiation taking place and offers some insight for production of biomimetic radioprotective materials.

Turick, C.; Ekechukwu, A.; Milliken, C.

2011-05-17T23:59:59.000Z

174

The Estimation of Molecular and Cytogenetic Effects in Mice Exposed to Chronic Low Dose-Rate Gamma-Radiation  

Science Journals Connector (OSTI)

Molecular and cytogenetic parameters were estimated in male CBA/lac mice exposed to chronic low dose-rate ?-radiation (62 cGy/year) for 40, 80, 120, 210, and 365 days. After 40 days of exposure (6.7 cGy), sple...

A. N. Osipov; A. L. Elakov; P. V. Puchkov…

2002-10-01T23:59:59.000Z

175

E-Print Network 3.0 - area gamma radiation Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

POWER LAW SPECTRA OF GAMMARAY BURSTS Summary: SMOOTHLY BROKEN POWER LAW SPECTRA OF GAMMA-RAY BURSTS F. Ryde Stockholm Observatory, SE-133 36... . It is used to fit Gamma-Ray Burst...

176

Energy resolution in semiconductor gamma radiation detectors using heterojunctions and methods of use and preparation thereof  

DOE Patents [OSTI]

In one embodiment, a system comprises a semiconductor gamma detector material and a hole blocking layer adjacent the gamma detector material, the hole blocking layer resisting passage of holes therethrough. In another embodiment, a system comprises a semiconductor gamma detector material, and an electron blocking layer adjacent the gamma detector material, the electron blocking layer resisting passage of electrons therethrough, wherein the electron blocking layer comprises undoped HgCdTe. In another embodiment, a method comprises forming a hole blocking layer adjacent a semiconductor gamma detector material, the hole blocking layer resisting passage of holes therethrough. Additional systems and methods are also presented.

Nikolic, Rebecca J.; Conway, Adam M.; Nelson, Art J.; Payne, Stephen A.

2012-09-04T23:59:59.000Z

177

Discovering Clinical Biomarkers of Ionizing Radiation Exposure with Serum Proteomic Analysis  

Science Journals Connector (OSTI)

...with a wide range of diagnoses and radiation treatment...and during ionizing radiation...from low dose-volume...of a wide range of diagnoses...volume, and dose of radiotherapy...exposed to ionizing radiation between the...with a wide range of diagnoses and radiation treatment...and during ionizing radiation...from low dose-volume...

Cynthia Ménard; Donald Johann; Mark Lowenthal; Thierry Muanza; Mary Sproull; Sally Ross; James Gulley; Emanuel Petricoin; C. Norman Coleman; Gordon Whiteley; Lance Liotta; and Kevin Camphausen

2006-02-01T23:59:59.000Z

178

Relationship between Radiation Exposure and Risk of Second Primary Cancers among Atomic Bomb Survivors  

Science Journals Connector (OSTI)

...Welford, Department of Radiation Oncology, Case Western Reserve...case.edu 1 Department of Radiation Oncology, Case Western Reserve...Ohio. 2 Department of Radiation Oncology, Osaka University, Osaka, Japan. 3 School of Applied Sciences...

Christopher I. Li; Nobuo Nishi; Jean A. McDougall; Erin O. Semmens; Hiromi Sugiyama; Midori Soda; Ritsu Sakata; Mikiko Hayashi; Fumiyoshi Kasagi; Akihiko Suyama; Kiyohiko Mabuchi; Scott Davis; Kazunori Kodama; and Kenneth J. Kopecky

2010-09-15T23:59:59.000Z

179

Occupational exposure from external radiation used in medical practices in Pakistan by film badge dosimetry  

Science Journals Connector (OSTI)

......R. J. Manual on Radiation Dosimetry (1970...An Introduction of Radiation Protection (1986...Agency (IAEA). Safety series calibration of radiation protection instruments...Orfi S. D. Software RaDLab Ver. 1......

A. Jabeen; M. Munir; A. Khalil; M. Masood; P. Akhter

2010-08-01T23:59:59.000Z

180

Comparison of codes assessing galactic cosmic radiation exposure of aircraft crew  

Science Journals Connector (OSTI)

......the galactic cosmic radiation. Results are provided...fully satisfactory for radiation protection purposes...Protection and Nuclear Safety, F-92262 Fontenay-aux-Roses...Computer Simulation Cosmic Radiation Europe Humans Occupational...instrumentation methods Software Solar Activity...

J. F. Bottollier-Depois; P. Beck; B. Bennett; L. Bennett; R. Bütikofer; I. Clairand; L. Desorgher; C. Dyer; E. Felsberger; E. Flückiger; A. Hands; P. Kindl; M. Latocha; B. Lewis; G. Leuthold; T. Maczka; V. Mares; M. J. McCall; K. O'Brien; S. Rollet; W. Rühm; F. Wissmann

2009-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Escherichia coli Genes and Pathways Involved in Surviving Extreme Exposure to Ionizing Radiation  

Science Journals Connector (OSTI)

...doses of ionizing radiation does not depend on...the effects of high doses of ionizing radiation (IR). The repair...IR resistance. A range of modern screening...survive increasing doses of ionizing radiation in comparison to...

Rose T. Byrne; Stefanie H. Chen; Elizabeth A. Wood; Eric L. Cabot; Michael M. Cox

2014-07-21T23:59:59.000Z

182

Assessment of radon concentration and external gamma radiation level in the environs of Narwapahar uranium mine, India and its radiological significance  

Science Journals Connector (OSTI)

In the environs of uranium mining, milling and processing facilities and in the uranium mineralized terrain, a little higher ambient radon concentration and gamma radiation level may be expected in comparison ...

B. K. Rana; R. M. Tripathi; J. S. Meena…

2011-11-01T23:59:59.000Z

183

Abstract--We have recently completed a large-area, coded-aperture, gamma-ray imager for use in searching for radiation  

E-Print Network [OSTI]

Abstract-- We have recently completed a large-area, coded- aperture, gamma-ray imager for use. The in- strument uses a rank-19, one-dimensional coded aperture to cast shadow patterns onto a 0.57 m2 Na sufficient radiation can reach a large gamma-ray detec- tor from a small source to make detection possible

Horn, Berthold K.P.

184

Physical and biological properties of U.S. standard endotoxin EC after exposure to ionizing radiation.  

Science Journals Connector (OSTI)

...in the UV range, radiation treatment...pattern. Dose-related...effects of the ionizing radiation...milligram-per-milliliter range) (13...in the UV range, we found...ioniz- ing radiation. Regarding...effective, dose- dependent...EXPOSED TO IONIZING RADIATION...

G Csako; R J Elin; H D Hochstein; C M Tsai

1983-07-01T23:59:59.000Z

185

Gamma-Ray Signatures for State-Of-Health Analysis and Monitoring of Widely-Arrayed Radiation Portal Monitor Systems  

SciTech Connect (OSTI)

Pacific Northwest National Laboratory (PNNL) has deployed a large array of radiation portal monitors for the Department of Homeland Security U.S. Customs and Border Protection. These portal monitors scan incoming vehicles crossing the U.S. border and shipping containers leaving international ports for radioactive material via gamma-ray and neutron detection. Data produced and captured by these systems are recorded for every vehicle related to radiation signature, sensor/system status, and local background, as well as a host of other variables. Within the Radiation Portal Monitor Project at PNNL, state-of-health observation and analysis for the whole RPM system using these data to determine functionality and performance is being developed. (PIET-43741-TM-492)

Woodring, Mitchell L.; Ely, James H.; Angel, Linda K.; Wright, Ingrid H.; Eslinger, Melany A.; Pospical, A. Jill; Ellis, John E.

2008-05-15T23:59:59.000Z

186

Gamma radiation and dose rate investigations on the Adriatic islands of magmatic origin  

Science Journals Connector (OSTI)

......Gamma ray spectrometry in seawater The underwater measuring system...electronics for data acquisition, storage and transmission. The power...direct gamma ray spectrometry in seawater, the obtained spectrum from...spectrometric measurement in the seawater. Isotope Energy (keV) Net......

Branko Petrinec; Zdenko Franic; Nenad Leder; Christos Tsabaris; Tomislav Bituh; Gordana Marovic

2010-06-01T23:59:59.000Z

187

Transport and noise properties of Si nanowire channels with different lengths before and after gamma radiation treatment  

SciTech Connect (OSTI)

The transport properties of Si nanowire (NW) structures fabricated on the basis of silicon on insulator (SOI) wafers were studied using noise spectroscopy before and after treatment with small doses of gamma radiation. The total resistance obtained from the I-V characteristics of Si NW structures scaled perfectly with length. Normalized flicker noise demonstrated 1/L{sup 2} dependence, which is a characteristic of dominant noise contribution from near-contact regions. The behavior changed to 1/L dependence after a small dose (1×10{sup 4} Gy) of gamma radiation treatment. Comparison of the random telegraph signal (RTS) noise parameters in the samples with small lengths before and after the treatment revealed a decrease in RTS amplitude and a shift to a lower frequency range after gamma irradiation. These results confirmed that the main changes in the samples were related to strain relaxation near-contact regions. In addition, such treatment resulted in a considerable decrease in the scattering data of device parameters.

Li, Jing; Vitusevich, Svetlana; Pud, Sergii; Sydoruk, Viktor; Offenhäusser, Andreas [Peter Grünberg Institute, Forschungszentrum Jülich (Germany); Petrychuk, Mykhailo [Taras Shevchenko National University, Kiev (Ukraine); Danilchenko, Boris [Institute of Physics, NASU, Kiev (Ukraine)

2013-12-04T23:59:59.000Z

188

Polymorphisms in DNA Repair Genes, Medical Exposure to Ionizing Radiation, and Breast Cancer Risk  

Science Journals Connector (OSTI)

...Session Abstracts Treatment Radiation Therapy CTRC-AACR San...breast-conserving therapy in Japan: comparison of the treatment...Mitsumori 1 1 Department of Radiation Oncology and Image-Applied...Kyoto University, Kyoto, Japan 2 Department of Radiology...

Robert C. Millikan; Jon S. Player; Allan Rene deCotret; Chiu-Kit Tse; and Temitope Keku

2005-10-01T23:59:59.000Z

189

Estimation of the contribution of photon radiation for measurement of the exposure dose rate of neutron sources based on 252Cf  

Science Journals Connector (OSTI)

A method for the estimation of the contribution of photon radiation to the detector readings for measurement of the exposure dose rate and the equivalent activity of neutron ... screens and filters is considered....

N. F. Demchenko; R. N. Minvaliev; V. I. Shipilov…

2012-06-01T23:59:59.000Z

190

Projection of needs for gamma radiation sources and other radioisotopes and assessment of alternatives for providing radiation sources  

SciTech Connect (OSTI)

Pacific Northwest Laboratory reviewed the projected uses and demands for a variety of nuclear byproducts. Because the major large-scale near-term demand is for gamma irradiation sources, this report concentrates on the needs for gamma sources and evaluates the options for providing the needed material. Projections of possible growth in the irradiation treatment industry indicate that there will be a need for 180 to 320 MCi of /sup 60/Co (including /sup 137/Cs equivalent) in service in the year 2000. The largest current and projected use of gamma irradiation is for the sterilization of medical devices and disposable medical supplies. Currently, 40% of US disposable medical products are treated by irradiation, and within 10 years it is expected that 90% will be treated in this manner. Irradiation treatment of food for destruction of pathogens or parasites, disinfestation, or extension of allowable storage periods is estimated to require an active inventory of 75 MCi of /sup 60/Co-equivalent gamma source in about a decade. 90 refs., 7 figs., 25 tabs.

Ross, W.A.; Jensen, G.A.; Clark, L.L.; Eakin, D.E.; Jarrett, J.H.; Katayama, Y.B.; McKee, R.W.; Morgan, L.G.; Nealey, S.M.; Platt, A.M.; Tingey, G.L.

1989-06-01T23:59:59.000Z

191

Radiation exposure to the population of Europe following the Chernobyl accident  

Science Journals Connector (OSTI)

......based on the analysis and compilation...availability and reliability of the radiation...destroyed nuclear reactor, including...availability and reliability of radiation...based on the analysis and compilation...based on the analysis and compilation...availability and reliability of the radiation......

V. Drozdovitch; A. Bouville; N. Chobanova; V. Filistovic; T. Ilus; M. Kovacic; I. Malátová; M. Moser; T. Nedveckaite; H. Völkle; E. Cardis

2007-03-01T23:59:59.000Z

192

Collective Doses and Radiation Risks Due to Medical Diagnostic Exposures in Ukraine  

Science Journals Connector (OSTI)

......Due to Medical Diagnostic Exposures in Ukraine L. Kalmykov N. Pilipenko V. Korneeva...Ukrainian population and separate regions of Ukraine due to radiodiagnosis have been calculated...exposure due to X ray examinations in Ukraine have decreased about twice during the......

L. Kalmykov; N. Pilipenko; V. Korneeva

1997-02-01T23:59:59.000Z

193

National primary standard for the unit of air kerma, air kerma rate, exposure, exposure rate, and x- and gamma-ray energy flux  

Science Journals Connector (OSTI)

According to the recommendations of the International Commission on Radiation Units and Measurements (ICRU) [2], as well as government decrees of the Russian Federation [3...], at present the basic physical quant...

A. V. Oborin; A. Yu. Villevalde; S. G. Trofimchuk

2012-11-01T23:59:59.000Z

194

The similar effects of low-dose ionizing radiation and non-ionizing radiation from background environmental levels of exposure  

Science Journals Connector (OSTI)

The meltdown and release of radioactivity (ionizing radiation) from four damaged nuclear reactors at the Fukushima Nuclear Facility in Japan in March 2011 continues to contaminate air and ocean water even 1 year ...

Cindy Sage

2012-06-01T23:59:59.000Z

195

Study of the radiative decay J/psi. -->. gamma. eta. pi. /sup +/. pi. /sup -/  

SciTech Connect (OSTI)

The Mark III collaboration has performed a high statistics study of the reaction J/psi ..-->.. ..gamma..eta..pi../sup +/..pi../sup -/, with two different final states of the eta, eta ..-->.. ..gamma gamma.. and eta ..-->.. ..pi../sup 0/..pi../sup +/..pi../sup -/. Both modes have a broad structure from 1.2 to 1.9 GeV/c/sup 2/ and two structures, which decay via delta/sup + -/..pi../sup - +/, delta/sup + -/ ..-->.. eta..pi../sup + -/, are identified at 1.28 and 1.39 GeV/c/sup 2/. No signal is observed in the iota(1440) signal region.

Becker, J.J.; Blaylock, G.T.; Bolton, T.; Brown, J.S.; Bunnell, K.O.; Burnett, T.H.; Cassell, R.E.; Coffman, D.; Cook, V.; Coward, D.H.

1987-02-01T23:59:59.000Z

196

E-Print Network 3.0 - accompanying gamma radiation Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

in which they deliver... emission. This is often, but not always, accompanied by gamma ray emission. There are a few excited states... -9117 (734) 763-4540 fax kearfott@umich.edu...

197

Determining the Impact of Concrete Roadways on Gamma Ray Background Readings for Radiation Portal Monitoring Systems  

E-Print Network [OSTI]

locations have reported abnormally high gamma background count rates. The higher background data has been attributed, in part, to the concrete surrounding the portal monitors. Higher background can ultimately lead to more material passing through the RPMs...

Ryan, Christopher Michael

2012-07-16T23:59:59.000Z

198

Gamma radiolysis of chlorinated hydrocarbons  

SciTech Connect (OSTI)

This program is the Idaho National Engineering Laboratory (INEL) component of a joint collarborative effort with Lawrence Livermore National Laboratory (LLNL). The purpose of this effort is to demonstrate a viable process for breaking down hazardous halogenated organic wastes to simpler, non-hazardous waste using high energy ionizing radiation. The INEL effort focuses on the use of spent reactor fuel gamma radiation sources to decompose complex wastes such as PCBs. At LLNL, halogenated solvents such as carbon tetrachloride and trichloroethylene are being studied using accelerator radiation sources. The INEL irradiation experiments concentrated on a single PCB congener so that a limited set of decomposition reactions could be studied. The congener 2,2{prime}, 3,3{prime},4,5{prime},6,6{prime} - octachlorobiphenyl was examined following exposure to various gamma doses at the Advanced Test Reactor (AIR) spent fuel pool. The decomposition rates and products in several solvents are discussed. 3 refs.

Arbon, R.E.; Mincher, B.J.; Meikrantz, D.H.

1992-01-01T23:59:59.000Z

199

Gamma radiolysis of chlorinated hydrocarbons  

SciTech Connect (OSTI)

This program is the Idaho National Engineering Laboratory (INEL) component of a joint collarborative effort with Lawrence Livermore National Laboratory (LLNL). The purpose of this effort is to demonstrate a viable process for breaking down hazardous halogenated organic wastes to simpler, non-hazardous waste using high energy ionizing radiation. The INEL effort focuses on the use of spent reactor fuel gamma radiation sources to decompose complex wastes such as PCBs. At LLNL, halogenated solvents such as carbon tetrachloride and trichloroethylene are being studied using accelerator radiation sources. The INEL irradiation experiments concentrated on a single PCB congener so that a limited set of decomposition reactions could be studied. The congener 2,2{prime}, 3,3{prime},4,5{prime},6,6{prime} - octachlorobiphenyl was examined following exposure to various gamma doses at the Advanced Test Reactor (AIR) spent fuel pool. The decomposition rates and products in several solvents are discussed. 3 refs.

Arbon, R.E.; Mincher, B.J.; Meikrantz, D.H.

1992-08-01T23:59:59.000Z

200

Extending the response of the sum coincidence spectrometer to multiple gamma radiation cascades  

E-Print Network [OSTI]

). crystal of sodium iodide with the sample placed inside of it is used. For larger crystals there is less probability of part of the gamma-ray energy escaping. This method gives a high detection efficiency; however, the resolution of large crystals can... be limited by light collection problems. For precision gamma-ray spectroscopy, high resolution out-weighs the disadvantage of low detection efficiency. The three-crystal scintillation spectrometer, developed by Maieschein' and Bair5, gives higher counting...

Helton, Victor Dean

1964-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

On the conversion of blast wave energy into radiation in active galactic nuclei and gamma-ray bursts  

E-Print Network [OSTI]

It has been suggested that relativistic blast waves may power the jets of AGN and gamma-ray bursts (GRB). We address the important issue how the kinetic energy of collimated blast waves is converted into radiation. It is shown that swept-up ambient matter is quickly isotropised in the blast wave frame by a relativistic two-stream instability, which provides relativistic particles in the jet without invoking any acceleration process. The fate of the blast wave and the spectral evolution of the emission of the energetic particles is therefore solely determined by the initial conditions. We compare our model with existing multiwavelength data of AGN and find remarkable agreement.

Martin Pohl; Reinhard Schlickeiser

1999-11-24T23:59:59.000Z

202

Yearly Chnages of Radiation Exposure Doses Received by Workers in Radiological Occupations at Kyushu University Hospital  

Science Journals Connector (OSTI)

......by Workers in Radiological Occupations at Kyushu University Hospital Hideo Irie * Chikara Takei * Shigeki Momii * Takehiko Higuchi...by workers in radiological occupations at Kyushu University Hospital from September 1962 to March 1966 were reported. The exposure......

Hideo Irie; Chikara Takei; Shigeki Momii; Takehiko Higuchi; Sigeaki Okamura; Kouji Masuda

1967-09-01T23:59:59.000Z

203

E-Print Network 3.0 - acute radiation exposure Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

chloride 100-44-7) and benzoyl chloride 98-88-4 (combined exposures) IARC-2A Acrolein Acutely... toxins, biotoxins and acutely toxic substances is not exhaustive Chemical...

204

Discovering Clinical Biomarkers of Ionizing Radiation Exposure with Serum Proteomic Analysis  

Science Journals Connector (OSTI)

...Libby Morimoto Public Health Sciences, Fred Hutchinson...the mutagenic effect of depleted uranium exposure in Gulf War...research, and public health impact. Nicholas Lang...the impact on public health, asking What are we...

Cynthia Ménard; Donald Johann; Mark Lowenthal; Thierry Muanza; Mary Sproull; Sally Ross; James Gulley; Emanuel Petricoin; C. Norman Coleman; Gordon Whiteley; Lance Liotta; and Kevin Camphausen

2006-02-01T23:59:59.000Z

205

Enhancement of natural background gamma-radiation dose around uranium microparticles in the human body  

Science Journals Connector (OSTI)

...photoelectrons. For most ionizing radiations, a large proportion...the absorbed dose is deposited...having a shorter range and being more strongly ionizing close to the...in high local doses, causing damage...enhancement of the radiation dose in volumes...

2010-01-01T23:59:59.000Z

206

FY08 Annual Report: Amorphous Semiconductors for Gamma Radiation Detection (ASGRAD)  

SciTech Connect (OSTI)

This is the annual report for an old project funded by NA22. The purpose of the project was to develop amorphous semiconductors for use as radiation detectors. The annual report contains information about the progress made in synthesizing, characterizing, and radiation response testing of these new materials.

Johnson, Bradley R.; Riley, Brian J.; Crum, Jarrod V.; Ryan, Joseph V.; Sundaram, S. K.; McCloy, John S.; Rockett, Angus

2009-02-01T23:59:59.000Z

207

Radiation exposure in X-ray-based imaging techniques used in osteoporosis  

E-Print Network [OSTI]

radiation dose compared with the X- ray examinations commonly used in routine clinical practice for the estimationradiation dose data and appropriate risk coef?cients provided by scienti?c committees. Risk estimation

Damilakis, John; Adams, Judith E.; Guglielmi, Giuseppe; Link, Thomas M.

2010-01-01T23:59:59.000Z

208

A Personal Experience Reducing Radiation Exposures: Protecting Family in Kiev during the First Two Weeks after Chernobyl  

SciTech Connect (OSTI)

The Chernobyl nuclear reactor accident occurred in 1986. The plume from the explosions and fires was highly radioactive and resulted in very high exposure levels in the surrounding regions. This paper describes how the people in Kiev, Ukraine, a city 90 miles (120 km) south of Chernobyl, and in particular one individual in that city, Professor Vitaly Eremenko, became aware of the threat before the official announcement and the steps he took to mitigate potential impacts to his immediate family. The combination of being informed and using available resources led to greatly reduced consequences for his family and, in particular, his newborn granddaughter. He notes how quickly word of some aspects of the hazard spread in the city and how other aspects appear to not have been understood. Although these events are being recalled as the 20th anniversary of the terrible event approaches, the lessons are still pertinent today. Threats of possible terrorist use of radiation dispersal devices makes knowledge of effective individual actions for self-protection from radiation exposures a topic of current interest.

Eremenko, Vitaly A.; Droppo, James G.

2006-08-01T23:59:59.000Z

209

Effects of fetal microwave radiation exposure on offspring behavior in mice  

Science Journals Connector (OSTI)

......In the developing nervous system, the brain tissue is more conductive than that of...neuronal functions and synaptic plasticity in brain slice preparations of rats exposed either...et al. Nerve cell damage in mammalian brain after exposure to microwaves from GSM mobile......

Yanchun Zhang; Zhihui Li; Yan Gao; Chenggang Zhang

2014-10-01T23:59:59.000Z

210

MODIFICATION OF SHIRT BUTTONS FOR RETROSPECTIVE RADIATION DOSIMETRY AFTER A RADIOLOGICAL EVENT  

E-Print Network [OSTI]

are presented for a personal radiation dosimeter in the form of a clothing button to provide gamma-ray dose estimation for clinically-significant external radiation exposures to the general public due of people might receive significant doses of radiation. The dose received by an individual from external

Brenner, David Jonathan

211

Miniaturized radiation chirper  

DOE Patents [OSTI]

The disclosure relates to a miniaturized radiation chirper for use with a small battery supplying on the order of 5 volts. A poor quality CdTe crystal which is not necessarily suitable for high resolution gamma ray spectroscopy is incorporated with appropriate electronics so that the chirper emits an audible noise at a rate that is proportional to radiation exposure level. The chirper is intended to serve as a personnel radiation warning device that utilizes new and novel electronics with a novel detector, a CdTe crystal. The resultant device is much smaller and has much longer battery life than existing chirpers.

Umbarger, C. John (Los Alamos, NM); Wolf, Michael A. (Los Alamos, NM)

1980-01-01T23:59:59.000Z

212

OBSERVATIONAL SIGNATURES OF SUB-PHOTOSPHERIC RADIATION-MEDIATED SHOCKS IN THE PROMPT PHASE OF GAMMA-RAY BURSTS  

SciTech Connect (OSTI)

A shock that forms below the photosphere of a gamma-ray burst (GRB) outflow is mediated by Compton scattering of radiation advected into the shock by the upstream fluid. The characteristic scale of such a shock, a few Thomson depths, is larger than any kinetic scale involved by several orders of magnitude. Hence, unlike collisionless shocks, radiation-mediated shocks cannot accelerate particles to nonthermal energies. The spectrum emitted by a shock that emerges from the photosphere of a GRB jet reflects the temperature profile downstream of the shock, with a possible contribution at the highest energies from the shock transition layer itself. We study the properties of radiation-mediated shocks that form during the prompt phase of GRBs and compute the time-integrated spectrum emitted by the shocked fluid following shock breakout. We show that the time-integrated emission from a single shock exhibits a prominent thermal peak, with the location of the peak depending on the shock velocity profile. We also point out that multiple shock emission can produce a spectrum that mimics a Band spectrum.

Levinson, Amir, E-mail: Levinson@wise.tau.ac.il [School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978 (Israel); JILA, University of Colorado and National Institute of Standards and Technology, 440 UCB, Boulder, CO 80309-0440 (United States)

2012-09-10T23:59:59.000Z

213

Strategy to detect the gravitational radiation counterpart of gamma-ray bursts  

E-Print Network [OSTI]

Both observational and theoretical rates of binary neutron star coalescence give low prospects for detection of a single event by the initial LIGO/VIRGO interferometers. However, by utilizing at the best all the a priori information on the expected signal, a positive detection can be achieved. This relies on the hypothesis that $\\gamma$-ray bursts are the electromagnetic signature of neutron star coalescences. The information about the direction of the source can then be used to add in phase the signals from different detectors in order (i) to increase the signal-to-noise ratio and (ii) to make the noise more Gaussian. Besides, the information about the time of arrival can be used to drastically decrease the observation time and thereby the false alarm rate. Moreover the fluence of the $\\gamma$-ray emission gives some information about the amplitude of the gravitational signal. One can then add the signals from $\\sim 10^4$ observation boxes ($\\sim$ number of $\\gamma$-ray bursts during 10 years) to yield a positive detection. Such a detection, based on the Maximum a Posteriori Probability Criterium, is a minimal one, in the sense that no information on the position and time of the events, nor on any parameter of the model, is collected. The advantage is that this detection requires an improvement of the detector sensitivity by a factor of only $\\sim 1.5$ with respect to the initial LIGO/VIRGO interferometers, and that, if positive, it will confirm the $\\gamma$-ray burst model.

S. Bonazzola; E. Gourgoulhon

1998-01-16T23:59:59.000Z

214

Estimation of the committed radiation dose resulting from gamma radionuclides ingested with food  

Science Journals Connector (OSTI)

The objective of the study was to estimate the value of the radiation dose absorbed in consequence of consumption of popular food products for individual age groups. Potatoes, corn and sugar beet were selected...

Piotr Gody?; Agnieszka Do?ha?czuk-?ródka…

2014-03-01T23:59:59.000Z

215

Assessment of radiation exposure in the uranium mining and milling area of Mailuu Suu, Kyrgyzstan  

Science Journals Connector (OSTI)

The area of the town of Mailuu Suu, Kyrgyzstan, is polluted by radionuclides and heavy metals from tailing dumps and heaps resulting from the historic exploitation of uranium mines. In the frame of a European Commission-TACIS funded project, radiological assessment was performed for critical group members living in the city of Mailuu Suu, located downstream the tailings, or in the village of Kara Agach, partially located on a uranium mine waste dump. The actual external exposure is around 1.2 mSv a?1 at both locations and exposure from radon is around 3 mSv a?1 at Mailuu Suu and around 10 mSv a?1 at Kara Agach. Ingestion dose was negligible for a critical group member living at Mailuu Suu. At Kara Agach, however, under the hypothesis that all food and fodder is cultivated locally, exposure from ingestion is much higher (?10–30 mSv a?1). In case of an accidental scenario [(part of) Tailing 3 content thrust to river], estimated additional maximum doses result in 45 and 77 mSv for an adult and a child, respectively.

H. Vandenhove; L. Sweeck; D. Mallants; H. Vanmarcke; A. Aitkulov; O. Sadyrov; M. Savosin; B. Tolongutov; M. Mirzachev; J.J. Clerc; H. Quarch; A. Aitaliev

2006-01-01T23:59:59.000Z

216

Occupational exposure to ionising radiation with thermoluminescence dosimetry system in Turkey, in 2003  

Science Journals Connector (OSTI)

......communication between reader and software via an RS-232C port...main functions of this software are data and glow-curve...included in the new software. Monitored and exposed...monitoring period. Radiation workers who may be exposed...60(3) and in the Safety Series No. 115(7......

C. T. Zeyrek; H. Gündüz

2005-05-01T23:59:59.000Z

217

Escherichia coli Genes and Pathways Involved in Surviving Extreme Exposure to Ionizing Radiation  

Science Journals Connector (OSTI)

...doses of ionizing radiation does not depend on a single mechanism...metabolism (2). This listing does not include a few gene products...from Deinococcus radiodurans R1 does not restore radioresistance...genetics: a laboratory manual and handbook for Escherichia coli and related...

Rose T. Byrne; Stefanie H. Chen; Elizabeth A. Wood; Eric L. Cabot; Michael M. Cox

2014-07-21T23:59:59.000Z

218

Photon Activation Analysis Of Light Elements Using 'Non-Gamma' Radiation Spectroscopy - The Instrumental Determination Of Phosphorus  

SciTech Connect (OSTI)

Unlike metal determinations the analysis of light elements (e.g., carbon, oxygen, phosphorus) is frequently problematic, in particular if analysed instrumentally. In photon activation analysis (PAA) the respective activation products do not emit gamma radiation in the most cases. Usually, annihilation quanta counting and subsequent decay curve analysis have been used for determinations of C, N, O, and F. However, radiochemical separation of the respective radioisotopes mostly is indispensable. For several reasons, some of the light elements cannot be analysed following this procedure, e.g. phosphorus. In this contribution the instrumental PAA of phosphorus in organic matrix by activation with bremsstrahlung of an electron linear accelerator and subsequent beta spectroscopy is described. The accuracy of the results was excellent as obtained by analysis of a BCR Reference Material.

Segebade, Christian [Idaho Accelerator Centre (IAC), Idaho State University, 1500 Alvin Ricken Drive, Pocatello, ID 83201 (United States); Goerner, Wolf [Bundesanstalt fuer Materialforschung und -pruefung, unter den Eichen 86, 12205 Berlin (Germany)

2011-06-01T23:59:59.000Z

219

Search for Dimuon Decays of a Light Scalar in Radiative Transitions Y(3S) -> gamma A0  

SciTech Connect (OSTI)

The fundamental nature of mass is one of the greatest mysteries in physics. The Higgs mechanism is a theoretically appealing way to account for the different masses of elementary particles and implies the existence of a new, yet unseen particle, the Higgs boson. We search for evidence of a light scalar (e.g. a Higgs boson) in the radiative decays of the narrow {Upsilon}(3S) resonance: {Upsilon}(3S) {yields} {gamma}A{sup 0}, A{sup 0} {yields} {mu}{sup +}{mu}{sup -}. Such an object appears in extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. We find no evidence for such processes in a sample of 122 x 10{sup 6} {Upsilon}(3S) decays collected by the BABAR collaboration at the PEP-II B-factory, and set 90% C.L. upper limits on the branching fraction product {Beta}({Upsilon}(3S) {yields} {gamma}A{sup 0}) x {Beta}(A{sup 0} {yields} {mu}{sup +}{mu}{sup -}) at (0.25 - 5.2) x 10{sup -6} in the mass range 0.212 {<=} m{sub A{sup 0}} {<=} 9.3 GeV. We also set a limit on the dimuon branching fraction of the {eta}{sub b} meson {Beta}({eta}{sub b} {yields} {mu}{sup +}{mu}{sup -}) < 0.8% at 90% C.L. The results are preliminary.

Aubert, B

2009-06-02T23:59:59.000Z

220

CONTRIBUTION OF GAMMA-RAY-LOUD RADIO GALAXIES' CORE EMISSIONS TO THE COSMIC MeV AND GeV GAMMA-RAY BACKGROUND RADIATION  

SciTech Connect (OSTI)

The Fermi gamma-ray satellite has recently detected gamma-ray emissions from radio galaxy cores. From these samples, we first examine the correlation between the luminosities at 5 GHz, L{sub 5GHz}, and at 0.1-10 GeV, L{sub {gamma}}, of gamma-ray-loud radio galaxies. We find that the correlation is significant with L{sub {gamma}}{proportional_to}L{sup 1.16}{sub 5GHz} based on a partial correlation analysis. Using this correlation and the radio luminosity function (RLF) of radio galaxies, we explore the contribution of gamma-ray-loud radio galaxies to the unresolved extragalactic gamma-ray background (EGRB). The gamma-ray luminosity function is obtained by normalizing the RLF to reproduce the source-count distribution of the Fermi gamma-ray-loud radio galaxies. We find that gamma-ray-loud radio galaxies can explain {approx}25% of the unresolved Fermi EGRB flux above 100 MeV and will also make a significant contribution to the EGRB in the 1-30 MeV energy band. Since blazars explain 22% of the EGRB above 100 MeV, radio-loud active galactic nucleus populations explain {approx}47% of the unresolved EGRB. We further make an interpretation on the origin of the EGRB. The observed EGRB spectrum at 0.2-100 GeV does not show an absorption signature by the extragalactic background light. Thus, the dominant population of the origin of EGRB at very high energy (>30 GeV) might be either nearby gamma-ray-emitting sources or sources with very hard gamma-ray spectra.

Inoue, Yoshiyuki, E-mail: yinoue@kusastro.kyoto-u.ac.jp [Department of Astronomy, Kyoto University, Kitashirakawa, Sakyo-ku, Kyoto 606-8502 (Japan)

2011-05-20T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Luffa fibers and gamma radiation as improvement tools of polymer Gonzalo Martnez-Barrera a,  

E-Print Network [OSTI]

, 4200-465 Porto, Portugal c Institute of Mechanical Engineering and Industrial Management (INEGI. The highest bending deformation is obtained with 0.9 wt% of fibers and 100 kGy of radiation dose. Ă? 2013, silica fume, silica sand; the last one the most used due to size distribution, ranging from 0.6 to 4.0 mm

North Texas, University of

222

SRNL Deploys Innovative Radiation Mapping Device | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

SRNL Deploys Innovative Radiation Mapping Device SRNL Deploys Innovative Radiation Mapping Device SRNL Deploys Innovative Radiation Mapping Device November 3, 2011 - 12:00pm Addthis The Savannah River National Laboratory completed successful deployments of the RadBall, a gamma radiation-mapping device. The Savannah River National Laboratory completed successful deployments of the RadBall, a gamma radiation-mapping device. AIKEN, S.C. - The Savannah River National Laboratory (SRNL), EM's national lab, has made strides with remote technology designed to reduce worker exposure while measuring radiation in contaminated areas. uilding on a successful collaboration with the United Kingdom's National Nuclear Laboratory, SRNL completed successful deployments of RadBall, a gamma radiation-mapping device, after testing the technology. The device

223

Analysis of radiation exposure for naval units of Operation Crossroads. Volume 2. (Appendix A) target ships. Technical report  

SciTech Connect (OSTI)

External radiation doses are reconstructed for crews of support and target ships of Joint Task Force One at Operation CROSSROADS, 1946. Volume I describes the reconstruction methodology, which consists of modeling the radiation environment, to include the radioactivity of lagoon water, target ships, and support ship contamination; retracing ship paths through this environment; and calculating the doses to shipboard personnel. The USS RECLAIMER, a support ship, is selected as a representative ship to demonstrate this methodology. Doses for all other ships are summarized. Volume II (Appendix A) details the results for target ship personnel. Volume III (Appendix B) details the results for support ship personnel. Calculated doses for more than 36,000 personnel aboard support ships while at Bikini range from zero to 1.7 rem. Of those, approximately 34,000 are less than 0.5 rem. From the models provided, doses due to target ship reboarding and doses accrued after departure from Bikini can be calculated, based on the individual circumstances of exposure.

Weitz, R.; Thomas, C.; Klemm, J.; Stuart, J.; Knowles, M.

1982-03-03T23:59:59.000Z

224

Analysis of radiation exposure for naval units of Operation Crossroads. Volume 3. (Appendix B) support ships. Technical report  

SciTech Connect (OSTI)

External radiation doses are reconstructed for crews of support and target ships of Joint Task Force One at Operation CROSSROADS, 1946. Volume I describes the reconstruction methodology, which consists of modeling the radiation environment, to include the radioactivity of lagoon water, target ships, and support ship contamination; retracing ship paths through this environment; and calculating the doses to shipboard personnel. The USS RECLAIMER, a support ship, is selected as a representative ship to demonstrate this methodology. Doses for all other ships are summarized. Volume II (Appendix A) details the results for target ship personnel. Volume III (Appendix B) details the results for support ship personnel. Calculated doses for more than 36,000 personnel aboard support ships while at Bikini range from zero to 1.7 rem. Of those approximately 34,000 are less than 0.5 rem. From the models provided, doses due to target ship reboarding and doses accrued after departure from Bikini can be calculated, based on the individual circumstances of exposure.

Weitz, R.; Thomas, C.; Klemm, J.; Stuart, J.; Knowles, M.

1982-03-03T23:59:59.000Z

225

Radiation exposure during liver surgery after treatment with 90Y microspheres, evaluated with computer simulations and dosimeter measurements  

Science Journals Connector (OSTI)

Purpose. Two patients with liver tumours were planned for a combined treatment, including surgery with preceding injections of ?? radiation emitting 90Y microspheres (SIRTEX®). The aim of this paper is to present a method of pre-surgical computer simulations of the absorbed dose rate on the surface of tumour tissue, combined with measurements of the actual absorbed dose rate on resected tissue, in order to estimate the absorbed dose to a surgeon's fingers during such surgery procedures. Methods and Materials. The dose rates from ?? radiation on the surface of tumour tissue were simulated with the software VARSKIN® Mod 2. The activity concentrations in tumours were estimated, based on SPECT/CT distribution studies of 99mTc-MAA and confirmed by SPECT/CT bremsstrahlung studies of 90Y microspheres. The activity distributions were considered as homogeneous within the tumour regions. The absorbed dose rates at different tumour tissue spots were calculated based on measurements with thermo-luminescent dosimeters (TLD) fastened on resected tissue. Results. The simulations showed a good agreement with the averaged absorbed dose rates based on TLD measurements performed on resected tissue, differing by 13% and 4% respectively. The absorbed dose rates at the measured maximum hotspots were twice as high as the average dose rates for both patients. Conclusion. The data is not sufficient in order to draw any general conclusions about dose rates on tumour tissue during similar surgeries, neither about the influence of dose rate heterogeneities nor about average dose rates. However, the agreement between simulations and measurements on these limited data indicate that this approach is a promising method for estimations of the radiation exposure to the surgeons' fingers during this kind of surgery procedure. More data from similar surgeries are necessary in order to validate the method.

Jonas Högberg; Magnus Rizell; Ragnar Hultborn; Johanna Svensson; Olof Henrikson; Peter Gjertsson; Peter Bernhardt

2012-01-01T23:59:59.000Z

226

SHP-2 tyrosine phosphate-dependent focal adhesion kinase mediated cell migration of primary endothelial cells upon low LET radiation exposure  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

SHP-2 tyrosine phosphate-dependent focal adhesion kinase mediated cell SHP-2 tyrosine phosphate-dependent focal adhesion kinase mediated cell migration of primary endothelial cells upon low LET radiation exposure Xiangpeng Zheng, 1 Sumathy Mohan, 3 and Mohan Natarajan 1,2 Departments of 1 Otolaryngology, 2 Radiation Oncology, and 3 Pathology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229 The influence and mechanism of low LET radiation exposure on wound healing process is not yet fully understood. Based on the vital role of endothelial cells in migration and wound healing, this study investigated the response of endothelial cells to low-dose irradiation and the underlying mechanism. A wound was inflicted in the confluent monolayer of primary vascular endothelial cells exposing a cell-free zone on the plate. The cells were then exposed

227

Analysis of radiation exposure for naval personnel at Operation Ivy. Technical report  

SciTech Connect (OSTI)

The radiological environments are reconstructed for eighteen ships and the residence islands of Enewetak, Kwajalein, and Bikini Atolls that received fallout following Shots MIKE and KING during Operation IVY (November 1952). Secondary (late-time) fallout from Shot MIKE was the primary contributor to the low-level radiation encountered on the majority of the ships and atolls; only the M/V HORIZON received primary (early-time) fallout from this event. Fallout from Shot KING was minimal. From the reconstructed operations and radiological environments, equivalent personnel film badge doses are calculated and compared with available dosimetry data for fourteen of the ships. Calculated doses for the majority of the ships are in good agreement with the film badge data; however, for three of the participating destroyers (DDEs), calculated doses are significantly lower than the dosimetry data indicates. Calculated mean doses for typical shipboard personnel range from a high of 0.062 rem on the HORIZON to a low of 0.001 rem on the SPENCER F. BAIRD; for island-based personnel, calculated mean doses are less than 0.06 rem.

Thomas, C.; Goetz, J.; Stuart, J.; Klemm, J.

1983-03-15T23:59:59.000Z

228

Occupational radiation exposure at commercial nuclear power reactors and other facilities 1996: Twenty-ninth annual report. Volume 18  

SciTech Connect (OSTI)

This report summarizes the occupational exposure data that are maintained in the US Nuclear Regulatory Commission`s (NRC) Radiation Exposure Information and Reporting System (REIRS). The bulk of the information contained in the report was compiled from the 1996 annual reports submitted by six of the seven categories of NRC licensees subject to the reporting requirements of 10 CFR 20.2206. Since there are no geologic repositories for high level waste currently licensed, only six categories will be considered in this report. Annual reports for 1996 were received from a total of 300 NRC licensees, of which 109 were operators of nuclear power reactors in commercial operation. Compilations of the reports submitted by the 300 licensees indicated that 138,310 individuals were monitored, 75,139 of whom received a measurable dose. The collective dose incurred by these individuals was 21,755 person-cSv (person-rem){sup 2} which represents a 13% decrease from the 1995 value. The number of workers receiving a measurable dose also decreased, resulting in the average measurable dose of 0.29 cSv (rem) for 1996. The average measurable dose is defined to be the total collective dose (TEDE) divided by the number of workers receiving a measurable dose. These figures have been adjusted to account for transient reactor workers. Analyses of transient worker data indicate that 22,348 individuals completed work assignments at two or more licensees during the monitoring year. The dose distributions are adjusted each year to account for the duplicate reporting of transient workers by multiple licensees. In 1996, the average measurable dose calculated from reported was 0.24 cSv (rem). The corrected dose distribution resulted in an average measurable dose of 0.29 cSv (rem).

Thomas, M.L. [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Regulatory Applications; Hagemeyer, D. [Science Applications International Corp., Oak Ridge, TN (United States)

1998-02-01T23:59:59.000Z

229

Effect of {gamma}-ray radiation on electrical properties of heat-treated Tb{sub x}Sn{sub 1-x}Se single crystals  

SciTech Connect (OSTI)

The effect of {gamma}-ray radiation on the electrical properties of heat-treated Tb{sub 0.01}Sn{sub 0.99}Se (sample 1) and Tb{sub 0.05}Sn{sub 0.95}Se (sample 2) samples is studied. It is found that, as a result of irradiation with {gamma}-ray 1.25-MeV photons, the charge-carrier concentration decreases in the temperature range T = 77-200 K by 17 and 6.3% for samples 1 and 2, respectively. It is assumed that, in the course of irradiation with {gamma}-ray photons, terbium impurity atoms are located between sites of the crystal lattice; in addition, Frenkel defects are formed.

Huseynov, J. I., E-mail: cih_58@mail.ru; Jafarov, T. A. [Azerbaijan State Pedagogical University (Azerbaijan)

2012-04-15T23:59:59.000Z

230

Hubble diagrams of soft and hard radiation sources in the graviton background: to an apparent contradiction between supernova 1a and gamma-ray burst observations  

E-Print Network [OSTI]

In the sea of super-strong interacting gravitons, non-forehead collisions with gravitons deflect photons, and this deflection may differ for soft and hard radiations. As a result, the Hubble diagram would not be a universal function and it will have a different view for such sources as supernovae in visible light and gamma-ray bursts. Observations of these two kinds are compared here with the limit cases of the Hubble diagram.

Michael A. Ivanov

2007-01-10T23:59:59.000Z

231

Analysis of radiation exposure for Naval personnel at Operation Castle. Technical report, 1 January 1983-31 January 1984  

SciTech Connect (OSTI)

Film-badge doses are reconstructed for sixteen ships and the residence islands of Enewetak and Kwajalein Atolls resulting from the six nuclear detonations comprising Operation CASTLE (March-May 1954). Fallout from Shots BRAVO and ROMEO was the major source of contamination on most of the ships and islands. Varying amounts of fallout from Shots UNION, YANKEE, and NECTAR contributed somewhat to the total doses of the shipboard and island-based personnel; no fallout was experienced as a result of Shot KOON. Shipboard personnel received additional exposure from hulls and salt water piping systems that had become contaminated from operating in the radioactive waters of Bikini Lagoon. From the reconstructed radiation environments, both topside and below, an equivalent film badge dose is calculated and compared to actual dosimetry data. Agreement is very good during badged periods when the ships received significant fallout. When topside intensities were not documented, generally late in the operation when intensity levels were low, agreement is not as good. Calculated ship contamination doses of significance are in excellent agreement with limited available dosimetry data. Calculated average doses for shipboard personnel range from a low of 0.19 rem for the crew of the USS LST-825 to a high of 3.56 rem for the crew of the USS PHILIP. Average doses on the residence islands of Enewetak and Kwajalein Atolls are 1.09 rem and 0.32 rem, respectively.

Thomas, C.; Goetz, J.; Klemm, J.; Weitz, R.

1984-02-28T23:59:59.000Z

232

Estimation of risk from medical radiation exposure based on effective and organ dose: how much difference is there?  

Science Journals Connector (OSTI)

......Russian Basic Sanitary Radiation Protection Standards...Basic Sanitary Rules for Radiation Safety of 2010(3). It is...CT)(4). Although radiation dose is the primary...effective dose; this software is addressed to radiologists......

V. K. Ivanov; V. V. Kashcheev; S. Yu. Chekin; A. N. Menyaylo; E. A. Pryakhin; A. F. Tsyb; F. A. Mettler

2013-07-01T23:59:59.000Z

233

Review of exposure limits and experimental data for corneal and lenticular damage from short pulsed UV and IR laser radiation  

E-Print Network [OSTI]

of exposure limits ANSI Z136.16 . The IEC and ANSI laser safety standards use the term "Maximum Permissible

234

RADIATION EFFECTS ON EPOXY CARBON FIBER COMPOSITE  

SciTech Connect (OSTI)

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

235

Measurement of natural radioactivity and dose rate assessment of terrestrial gamma radiation in the soil of southern Punjab, Pakistan  

Science Journals Connector (OSTI)

......terrestrial background radiation mainly due to these...assess the population radiation doses(4-9). However...data are available on naturally occuring and artificial radionulides...order to assess the radiation doses for the general......

I. Fatima; J. H. Zaidi; M. Arif; M. Daud; S. A. Ahmad; S. N. A. Tahir

2008-01-01T23:59:59.000Z

236

Human In vivo Dose-Response to Controlled, Low-Dose Low Linear Energy Transfer Ionizing Radiation Exposure  

Science Journals Connector (OSTI)

...effects of low-dose low-linear energy transfer ionizing radiation (LDIR) in humans...direct evidence that doses in the range of 1 to 10 cGy...the intentional radiation of healthy tissue...the response to ionizing radiation. Attempts...

Zelanna Goldberg; David M. Rocke; Chad Schwietert; Susanne R. Berglund; Alison Santana; Angela Jones; Jörg Lehmann; Robin Stern; Ruixiao Lu; and Christine Hartmann Siantar

2006-06-15T23:59:59.000Z

237

Essay on the gamma ray laser  

E-Print Network [OSTI]

This work discusses the possibility of inducing the emission of gamma radiation from nuclear isomers by two-photon transitions, in the more general context of the problem of the amplification of gamma radiation.

Silviu Olariu

1999-07-18T23:59:59.000Z

238

Gamma activity and radiation dose in concrete building blocks used for construction of dwellings in Jos, Nigeria  

Science Journals Connector (OSTI)

......IAEA-RGU-1. The detection efficiency calibration of the detector was performed using a reference soil sample prepared by Rocketdyne Laboratories, CA, which is traceable to a mixed standard gamma source (No. 48772-356, from Analytic Inc., Atlanta......

J. A. Ademola; I. P. Farai

2006-12-01T23:59:59.000Z

239

Translocation analysis by the FISH-painting method for retrospective dose reconstruction in individuals exposed to ionizing radiation 10 years after exposure  

Science Journals Connector (OSTI)

Fluorescence in situ hybridization (FISH) is a powerful method largely used for detecting chromosomal rearrangements, translocations in particular, which are important biomarkers for dose assessment in case of human exposure to ionizing radiation. To test the possibility of using the translocation analysis by FISH-painting method in retrospective dose assessment, we carried out in vitro experiments in irradiated human lymphocytes, in parallel with the analysis of translocations in lymphocytes from 10 individuals, who were exposed to 137cesium in the Goiânia (Brazil) accident (samples collected 10 years after exposure). The in vitro dose–response curve for the genomic translocation frequencies (FGs) fits a linear quadratic model, according to the equation: Y=0.0243X2+0.0556X. The FG values were also calculated for the individuals exposed to 137cesium, ranging from 0.58 to 5.91 per 100 cells, and the doses were estimated and compared with the results obtained by dicentric analysis soon after the accident, taking the opportunity to test the validity of translocation analysis in retrospective biodosimetry. A tentative of retrospective dosimetry was performed, indicating that the method is feasible only for low level exposure (below 0.5 Gy), while for higher doses there is a need to apply appropriate correction factors, which take into consideration mainly the persistence of chromosomal translocations along with time, and the influence of endogenous and exogenous factors determining the inter-individual variability in the cellular responses to radiation.

Marjori L. Camparoto; Adriana T. Ramalho; Adayapalam T. Natarajan; Maria P. Curado; Elza T. Sakamoto-Hojo

2003-01-01T23:59:59.000Z

240

Literature Review of the Effects of Radiation and Temperature on the Aging of Concrete  

SciTech Connect (OSTI)

The open literature and accessible United States Department of Energy-sponsored reports were reviewed for the effects of radiation and temperature on concrete. No effects of radiation were found for exposures less than 1010 neutron/cm2 or 1010 Gy gamma for periods less than 50 years. Reductions in compressive and tensile strength and a marked increase in volume are reported for exposures greater than 1020 neutron/cm2 or 1010 rads of gamma. There are conflicting reports of damage for doses in the middle ranges.

D. L. Fillmore

2004-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Human In vivo Dose-Response to Controlled, Low-Dose Low Linear Energy Transfer Ionizing Radiation Exposure  

Science Journals Connector (OSTI)

...format from the National Center for Biotechnology Information...most peoples lives by industrial exposures and medical...California Davis Cancer Center, UCDHS. The authors...implications for risk assessment in both therapeutic...California Davis Cancer Center, Sacramento, 95817...

Zelanna Goldberg; David M. Rocke; Chad Schwietert; Susanne R. Berglund; Alison Santana; Angela Jones; Jörg Lehmann; Robin Stern; Ruixiao Lu; and Christine Hartmann Siantar

2006-06-15T23:59:59.000Z

242

Animal mortality resulting from uniform exposures to photon radiations: Calculated LD/sub 50/s and a compilation of experimental data  

SciTech Connect (OSTI)

Studies conducted during the 1950s and 1960s of radiation-induced mortality to diverse animal species under various exposure protocols were compiled into a mortality data base. Some 24 variables were extracted and recomputed from each of the published studies, which were collected from a variety of available sources, primarily journal articles. Two features of this compilation effort are (1) an attempt to give an estimate of the uniform dose received by the bone marrow in each treatment so that interspecies differences due to body size were minimized and (2) a recomputation of the LD/sub 50/ where sufficient experimental data are available. Exposure rates varied in magnitude from about 10/sup -2/ to 10/sup 3/ R/min. This report describes the data base, the sources of data, and the data-handling techniques; presents a bibliography of studies compiled; and tabulates data from each study. 103 refs., 44 tabs.

Jones, T.D.; Morris, M.D.; Wells, S.M.; Young, R.W.

1986-12-01T23:59:59.000Z

243

Rapid assessment of high-dose radiation exposures through scoring of cell-fusion-induced premature chromosome condensation and ring chromosomes  

Science Journals Connector (OSTI)

Abstract Analysis of premature chromosome condensation (PCC) mediated by fusion of G0-lymphocytes with mitotic CHO cells in combination with rapid visualization and quantification of rings (PCC-Rf) is proposed as an alternative technique for dose assessment of radiation-exposed individuals. Isolated lymphocytes or whole blood from six individuals were ?-irradiated with 5, 10, 15 and 20 Gy at a dose rate of 0.5 Gy/min. Following either 8- or 24-h post-exposure incubation of irradiated samples at 37 °C, chromosome spreads were prepared by standard PCC cytogenetic procedures. The protocol for PCC fusion proved to be effective at doses as high as 20 Gy, enabling the analysis of ring chromosomes and excess PCC fragments. The ring frequencies remained constant during the 8–24-h repair time; the pooled dose relationship between ring frequency (Y) and dose (D) was linear: Y = (0.088 ± 0.005) × D. During the repair time, excess fragments decreased from 0.91 to 0.59 chromatid pieces per Gy, revealing the importance of information about the exact time of exposure for dose assessment on the basis of fragments. Compared with other cytogenetic assays to estimate radiation dose, the PCC-Rf method has the following benefits: a 48-h culture time is not required, allowing a much faster assessment of dose in comparison with conventional scoring of dicentrics and rings in assays for chemically-induced premature chromosome condensation (PCC-Rch), and it allows the analysis of heavily irradiated lymphocytes that are delayed or never reach mitosis, thus avoiding the problem of saturation at high doses. In conclusion, the use of the PCC fusion assay in conjunction with scoring of rings in G0-lymphocytes offers a suitable alternative for fast dose estimation following accidental exposure to high radiation doses.

A.I. Lamadrid Boada; I. Romero Aguilera; G.I. Terzoudi; J.E. González Mesa; G. Pantelias; O. García

2013-01-01T23:59:59.000Z

244

Health effects of low-level radiation in shipyard workers. Final report: [Draft  

SciTech Connect (OSTI)

The Nuclear Shipyard Workers Study (NSWS) was designed to determine whether there is an excess risk of leukemia or other cancers associated with exposure to low levels of gamma radiation. The study compares the mortality experience of shipyard workers who qualified to work in radiation areas to the mortality of similar workers who hold the same types of jobs but who are not authorized to work in radiation areas. The population consists of workers from six government and two private shipyards.

Matanoski, G.M.

1991-06-01T23:59:59.000Z

245

Nuclear radiation-warning detector that measures impedance  

DOE Patents [OSTI]

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

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

2013-06-04T23:59:59.000Z

246

Technology, safety, and costs of decommissioning reference nuclear research and test reactors: sensitivity of decommissioning radiation exposure and costs to selected parameters  

SciTech Connect (OSTI)

Additional analyses of decommissioning at the reference research and test (R and T) reactors and analyses of five recent reactor decommissionings are made that examine some parameters not covered in the initial study report (NUREG/CR-1756). The parameters examined for decommissioning are: (1) the effect on costs and radiation exposure of plant size and/or type; (2) the effects on costs of increasing disposal charges and of unavailability of waste disposal capacity at licensed waste disposal facilities; and (3) the costs of and the available alternatives for the disposal of nuclear R and T reactor fuel assemblies.

Konzek, G.J.

1983-07-01T23:59:59.000Z

247

Neutron radiation can activate K-ras via a point mutation in codon 146 and induces a different spectrum of ras mutations than does gamma radiation.  

Science Journals Connector (OSTI)

research-article Research Article Neutron radiation can activate K-ras via a point...School of Medicine, New York 10016. Neutron radiation is known to produce tumors in...RF/J mice by a single acute dose of neutron irradiation. Activated ras genes were...

S R Sloan; E W Newcomb; A Pellicer

1990-01-01T23:59:59.000Z

248

RADIATION MECHANISM AND JET COMPOSITION OF GAMMA-RAY BURSTS AND GeV-TeV-SELECTED RADIO-LOUD ACTIVE GALACTIC NUCLEI  

SciTech Connect (OSTI)

Gamma-ray bursts (GRBs) and GeV-TeV-selected radio-loud active galactic nuclei (AGNs) are compared based on our systematic modeling of the observed spectral energy distributions of a sample of AGNs with a single-zone leptonic model. We show that the correlation between the jet power (P{sub jet}) and the prompt gamma-ray luminosity (L{sub jet}) of GRBs is consistent, within the uncertainties, with the correlation between jet power and the synchrotron peak luminosity (L{sub s,jet}) of flat spectrum radio quasars (FSRQs). Their radiation efficiencies ({epsilon}) are also comparable (>10% for most sources), which increase with the bolometric jet luminosity (L{sub bol,jet}) for FSRQs and with the L{sub jet} for GRBs with similar power-law indices. BL Lac objects (BL Lacs) do not follow the P{sub jet}-L{sub s,jet} relation of FSRQs. They have lower {epsilon} and L{sub bol,jet} values than FSRQs, and a tentative L{sub bol,jet}-{epsilon} relation is also found, with a power-law index different from that of the FSRQs. The magnetization parameters ({sigma}) of FSRQs are on average larger than that of BL Lacs. They are anti-correlated with {epsilon} for the FSRQs, but positively correlated with {epsilon} for the BL Lacs. GeV narrow-line Seyfert 1 galaxies potentially share similar properties with FSRQs. Based on the analogy between GRBs and FSRQs, we suggest that the prompt gamma-ray emission of GRBs is likely produced by the synchrotron process in a magnetized jet with high radiation efficiency, similar to FSRQs. The jets of BL Lacs, on the other hand, are less efficient and are likely more matter-dominated.

Zhang Jin; Lu Ye; Zhang Shuangnan [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Liang Enwei; Sun Xiaona [Department of Physics and GXU-NAOC Center for Astrophysics and Space Sciences, Guangxi University, Nanning 530004 (China); Zhang Bing, E-mail: lew@gxu.edu.cn [Department of Physics and Astronomy, University of Nevada, Las Vegas, NV 89154 (United States)

2013-09-01T23:59:59.000Z

249

Blazar Duty-Cycle at gamma-ray Frequecies: Constraints from Extragalactic Background Radiation and Prospects for AGILE and GLAST  

E-Print Network [OSTI]

We take into account the constraints from the observed extragalactic gamma-ray background to estimate the maximum duty cycle allowed for a selected sample of WMAP Blazars, in order to be detectable by AGILE and GLAST gamma-ray experiments. For the nominal sensitivity values of both instruments, we identify a subset of sources which can in principle be detectable also in a steady state without over-predicting the extragalactic background. This work is based on the results of a recently derived Blazar radio LogN-LogS obtained by combining several multi-frequency surveys.

Pittori, Carlotta; Colafrancesco, Sergio; Giommi, Paolo

2007-01-01T23:59:59.000Z

250

Blazar Duty-Cycle at gamma-ray Frequecies: Constraints from Extragalactic Background Radiation and Prospects for AGILE and GLAST  

E-Print Network [OSTI]

We take into account the constraints from the observed extragalactic gamma-ray background to estimate the maximum duty cycle allowed for a selected sample of WMAP Blazars, in order to be detectable by AGILE and GLAST gamma-ray experiments. For the nominal sensitivity values of both instruments, we identify a subset of sources which can in principle be detectable also in a steady state without over-predicting the extragalactic background. This work is based on the results of a recently derived Blazar radio LogN-LogS obtained by combining several multi-frequency surveys.

Carlotta Pittori; Elisabetta Cavazzuti; Sergio Colafrancesco; Paolo Giommi

2007-05-04T23:59:59.000Z

251

RADIATION CARCINOGENESIS IN MAN: INFLUENCE OF DOSE-RESPONSE MODELS AND RISK PROJECTION MODELS IN THE ESTIMATION OF RISK COEFFICIENTS FOLLOWING EXPOSURE TO LOW-LEVEL RADIATION  

E-Print Network [OSTI]

RADIATION CARCINOGENESIS IN MAN: INFLUENCE OF DOSE-RESPONSE MODELS AND RISK PROJECTION MODELS IN THE ESTIMATIONRADIATION CARCINOGENESIS IN HAN: INFLUENCE OF DOSE-RESPONSE MODELS AND RISK PROJECTION MODELS IN THE ESTIMATION

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

252

Dynamics of the xanthophyll cycle and non-radiative dissipation of absorbed light energy during exposure of Norway spruce to high irradiance  

Science Journals Connector (OSTI)

Summary The response of Norway spruce saplings (Picea abies [L.] Karst.) was monitored continuously during short-term exposure (10 days) to high irradiance (HI; 1000 ?mol m?2 s?1). Compared with plants acclimated to low irradiance (100 ?mol m?2 s?1), plants after HI exposure were characterized by a significantly reduced CO2 assimilation rate throughout the light response curve. Pigment contents varied only slightly during HI exposure, but a rapid and strong response was observed in xanthophyll cycle activity, particularly within the first 3 days of the HI treatment. Both violaxanthin convertibility under HI and the amount of zeaxanthin pool sustained in darkness increased markedly under HI conditions. These changes were accompanied by an enhanced non-radiative dissipation of absorbed light energy (NRD) and the acceleration of induction of both NRD and de-epoxidation of the xanthophyll cycle pigments. We found a strong negative linear correlation between the amount of sustained de-epoxidized xanthophylls and the photosystem II (PSII) photochemical efficiency (FV/FM), indicating photoprotective down-regulation of the PSII function. Recovery of FV/FM at the end of the HI treatment revealed that Norway spruce was able to cope with a 10-fold elevated irradiance due particularly to an efficient NRD within the PSII antenna that was associated with enhanced violaxanthin convertibility and a light-induced accumulation of zeaxanthin that persisted in darkness.

Michal Štroch; Kristina Kuldová; Ji?í Kalina; Vladimír Špunda

2008-01-01T23:59:59.000Z

253

Low Dose Radiation Research Program: DOE Lowdose Radiation Program Workshop  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Using a Low LET Electron Microbeam to Investigate Non-Targeted Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation. Authors: William F. Morgan1 and Marianne B. Sowa2 Institutions: 1Radiation Oncology Research Laboratory, University of Maryland, Baltimore MD 21201 2 Chemical Structure and Dynamics, Pacific Northwest National Laboratory, Richland WA 99352 We have recently installed a low LET electron microbeam that generates energetic electrons to mimic radiation damage from gamma and x-ray sources. It has been designed such that high-energy electrons deposit energy in a pre-selected subset of cells leaving neighboring cells unirradiated (Figure 1). In this way it is possible to examine non-targeted effects associated with low dose radiation exposure including induced genomic instability and

254

Calculation of gamma radiation dose rate and radon concentration due to granites used as building materials in Iran  

Science Journals Connector (OSTI)

......G. Magusa, North Cyprus, via Mersin 10, Turkey Natural radioactivity concentrations...equivalent from all natural sources of radiation...health(4). Radon gas is a radionuclide present...to determining the natural radioactivity concentration......

A. Abbasi

2013-07-01T23:59:59.000Z

255

Radioactive waste isolation in salt: geochemistry of brine in rock salt in temperature gradients and gamma-radiation fields - a selective annotated bibliography  

SciTech Connect (OSTI)

Evaluation of the extensive research concerning brine geochemistry and transport is critically important to successful exploitation of a salt formation for isolating high-level radioactive waste. This annotated bibliography has been compiled from documents considered to provide classic background material on the interactions between brine and rock salt, as well as the most important results from more recent research. Each summary elucidates the information or data most pertinent to situations encountered in siting, constructing, and operating a mined repository in salt for high-level radioactive waste. The research topics covered include the basic geology, depositional environment, mineralogy, and structure of evaporite and domal salts, as well as fluid inclusions, brine chemistry, thermal and gamma-radiation effects, radionuclide migration, and thermodynamic properties of salts and brines. 4 figs., 6 tabs.

Hull, A.B.; Williams, L.B.

1985-07-01T23:59:59.000Z

256

High-energy radiation visualizer (HERV): A new system for imaging in x-ray and gamma-ray emission regions  

SciTech Connect (OSTI)

The authors present a description and results of the operation for {gamma}-ray and X-ray objects for the compact visualization system high-energy radiation visualizer (HERV). The imaging in this system is based on use of a conical collimator, scintillator plate, and image intensifier as a detector and CCD matrix as a readout device. The use of HERV as a two-dimensional X-ray image visualizer for the Compton scatter inspection system was considered and first results are discussed. The possibility of using different hexagonal-coded apertures imaging for HERV is discussed and results of Monte Carlo simulation and experiments with optical analog of coded aperture are presented.

Sudarkin, A.N.; Ivanov, O.P.; Stepanov, V.E.; Volkovich, A.G.; Turin, A.S.; Danilovich, A.S.; Rybakov, D.D.; Urutskoev, L.I. [RECOM Ltd., Moscow (Russian Federation)] [RECOM Ltd., Moscow (Russian Federation)

1996-08-01T23:59:59.000Z

257

Risks from ionizing radiation  

Science Journals Connector (OSTI)

... RADON indoors now accounts for nearly half of the average UK population exposure to ionizing radiation ... exposure to ionizing radiation. We believe that the extent of the variation in exposure to radon in the United Kingdom and else-where and its magnitude in relation to exposures from ...

R. H. Clarke; T. R. E. Southwood

1989-03-16T23:59:59.000Z

258

Search for Invisible Decays of a Light Scalar in Radiative Transitions Upsilon(3S) -> gamma A0  

E-Print Network [OSTI]

We search for a light scalar particle produced in single-photon decays of the Upsilon(3S) resonance through the process Upsilon(3S) -> gamma A0, A0 -> invisible. Such an object appears in Next-to-Minimal Supersymmetric extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. If, in addition, there exists a light, stable neutralino, decays of A0 could be preferentially to an invisible final state. We search for events with a single high-energy photon and a large missing mass, consistent with a 2-body decay of Upsilon(3S). We find no evidence for such processes in a sample of 122*10^6 Upsilon(3S) decays collected by the BABAR collaboration at the PEP-II B-factory, and set 90% C.L. upper limits on the branching fraction B(Upsilon(3S) -> gamma A0)*B(A0 -> invisible) at (0.7-31)*10^{-6} in the mass range m(A0)<=7.8 GeV. The results are preliminary.

The BaBar Collaboration; B. Aubert

2008-07-31T23:59:59.000Z

259

Search for Invisible Decays of a Light Scalar in Radiative Transitions Y(3S)->gamma A0  

SciTech Connect (OSTI)

We search for a light scalar particle produced in single-photon decays of the {Upsilon}(3S) resonance through the process {Upsilon}(3S) {yields} {gamma} + A{sup 0}, A{sup 0} {yields} invisible. Such an object appears in Next-to-Minimal Supersymmetric extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. If, in addition, there exists a light, stable neutralino, decays of A{sup 0} could be preferentially to an invisible final state. We search for events with a single high-energy photon and a large missing mass, consistent with a 2-body decay of {Upsilon}(3S). We find no evidence for such processes in a sample of 122 x 10{sup 6} {Upsilon}(3S) decays collected by the BABAR collaboration at the PEP-II B-factory, and set 90% C.L. upper limits on the branching fraction {Beta}({Upsilon}(3S) {yields} {gamma}A{sup 0}) x {Beta}(A{sup 0} {yields} invisible) at (0.7-31) x 10{sup -6} in the mass range m{sub A{sup 0}} {le} 7.8 GeV. The results are preliminary.

Aubert, B

2008-11-05T23:59:59.000Z

260

Gamma ray bursts ROBERT S MACKAY  

E-Print Network [OSTI]

Gamma ray bursts ROBERT S MACKAY COLIN ROURKE We propose that a gamma ray burst is a kinematic Gamma ray bursts are intense flashes of electromagnetic radiation of cosmic origin lasting from ten accepted mechanism. We propose that a gamma ray burst is simply a kinematic effect, namely the effect

Rourke, Colin

Note: This page contains sample records for the topic "gamma radiation exposure" 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

The Polarization Dependence of Gamma-Gamma Absorption - Implications for Gamma-Ray Bursts and Blazars  

E-Print Network [OSTI]

This paper presents an analysis of the dependence of the opacity for high-energy gamma-rays to gamma-gamma absorption by low-energy photons, on the polarization of the gamma-ray and target photons. This process has so far only been considered using the polarization-averaged gamma-gamma absorption cross section. It is demonstrated that in the case of polarized gamma-ray emission, subject to source-intrinsic gamma-gamma absorption by polarized target photons, this may lead to a slight over-estimation of the gamma-gamma opacity by up to ~ 10 % in the case of a perfectly ordered magnetic field. Thus, for realistic astrophysical scenarios with partially ordered magnetic fields, the use of the polarization-averaged gamma-gamma cross section is justified for practical purposes, such as estimates of minimum Doppler factors inferred for gamma-ray bursts and blazars, based on gamma-gamma transparency arguments, and this paper quantifies the small error incurred by the unpolarized-radiation approximation. Furthermore, i...

Boettcher, Markus

2014-01-01T23:59:59.000Z

262

Influence of gamma radiation on the activities of some carbohydrate metabolic enzymes in the cotyledons and the leaves of fenugreek (Trigonella foenum-graecum L. ) bean seedlings  

SciTech Connect (OSTI)

Studies indicated that 21-day old cotyledons from gamma irradiated seeds of fenugreek beans were heavier and had more starch and sugar than their non-irradiated controls. To test whether these effects occurred in the leaves and to seek a possible biochemical explanation for these results, the activities of five enzymes involved in carbohydrate metabolism were studied. Three groups of fenugreek bean seeds were irradiated (100-300 Gy) and then allowed to grow for 21 days. On harvest, wet and dry weights of both cotyledons and leaves were determined. Starch and sugar contents in cotyledons and leaves were measured. The five enzymes ..cap alpha..-amylase, ..beta..-amylase, starch phosphorylase, ADPG-pyrophosphorylase and ribulose-1,5-diphosphate carboxylase were extracted from cotyledons and leaves, respectively. The protein contents and activities of the enzyme extracts were determined. The results suggest an increase in carbohydrate metabolism in cotyldeons and a decrease in leaves due to the radiation treatment of the seeds before germination. Thus, increased amounts of starch and sugars are observed in the cotyledons, and decreased amounts in the leaves. Radiation damage to the translocatory system of the plant may retard the movement of sugars from the cotyledons to the other parts of the plant. This may cause accumulation of sugars and starch in the cotyledons, leading to an increase in their size and weight.

Ahanotu, P.A.

1985-01-01T23:59:59.000Z

263

EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS (REVISION 1)  

SciTech Connect (OSTI)

Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Revision 1 adds a comparison with results of a study of tritium exposed EPDM. The amount of gas produced by the gamma irradiation was found to be equivalent to about 280 days exposure to initially pure tritium gas at one atmosphere. The glass transition temperature of the tritium exposed EPDM rose about 10 ?C. over 280 days, while no glass transition temperature change was observed for gamma irradiated EPDM. This means that gamma irradiation in deuterium cannot be used as a surrogate for tritium exposure.

Clark, E.

2013-09-13T23:59:59.000Z

264

Predicting the radiation exposure of terrestrial wildlife in the Chernobyl exclusion zone : an international comparison of approaches.  

SciTech Connect (OSTI)

There is now general acknowledgement that there is a requirement to demonstrate that species other than humans are protected from anthropogenic releases of radioactivity. A number of approaches have been developed for estimating the exposure of wildlife and some of these are being used to conduct regulatory assessments. There is a requirement to compare the outputs of such approaches against available data sets to ensure that they are robust and fit for purpose. In this paper we describe the application of seven approaches for predicting the whole-body ({sup 90}Sr, {sup 137}Cs, {sup 241}Am and Pu isotope) activity concentrations and absorbed dose rates for a range of terrestrial species within the Chernobyl exclusion zone. Predictions are compared against available measurement data, including estimates of external dose rate recorded by thermoluminescent dosimeters attached to rodent species. Potential reasons for differences between predictions between the various approaches and the available data are explored.

Beresford, N. A.; Barnett, C. L.; Brown, J. E.; Cheng, J.-J.; Copplestone, D.; Gaschak, S.; Hosseini, A.; Howard, B. J.; Kamboj, S.; Nedveckaite, T.; Olyslaegers, G.; Smith, J. T.; Vives i Batlle, J.; Vives-Lynch, S.; Yu, C.; Environmental Science Division; Centre for Ecology and Hydrology; Norwegian Radiation Protection Authority; England and Wales Environment Agency; International Radioecology Lab.; Inst. of Physics, Radiation Protection,; Belgian Nuclear Research Centre; Univ. of Portsmouth; Westlakes Research Inst.

2010-06-09T23:59:59.000Z

265

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

SciTech Connect (OSTI)

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

266

Gamma-Emitting Radionuclides in Newborns, Infants, and Children  

Science Journals Connector (OSTI)

...Isotopes Radiation Effects Radiation Monitoring Rubidium Thyroid...PLACENTA POTASSIUM ISOTOPES RADIATION EFFECTS RADIATION MONITORING RUBIDIUM THYROID...primary gamma photons from naturally occuring K" and fission prod-uct...

N. S. Macdonald; D. L. Hutchinson; D. L. Moyer; R. A. Chez

1963-09-13T23:59:59.000Z

267

Gamma doses from phospho-gypsum plaster-board  

SciTech Connect (OSTI)

The use of phospho-gypsum plaster-board and plaster cement in buildings as a substitute for natural gypsum may constitute an additional source of radiation exposure to both workers and members of the public, both from inhalation of radon progeny produced from radon which is exhaled from the plaster-board and from beta and gamma radiation produced by radioactive decay in the plaster-board. The calculations presented in this paper indicate that if phospho-gypsum sheets 1 cm thick containing a {sup 226}Ra concentration of 400 Bq kg{sup -1} are used to line the walls and ceiling of a room of dimensions up to 5 m {times} 5 m {times} 3 m, the annual effective dose from gamma radiation for a person continually occupying the room should not exceed approximately 0.13 mSv. This compares with a measured annual average effective dose from gamma radiation in Australian homes of 0.9 mSv. The annual effective dose from such thin sheets is directly proportional to the {sup 226}Ra concentration in the plaster-board. 13 refs., 6 figs.

O`Brien, R.S. [Australian Radiation Lab., Victoria (Australia)

1997-01-01T23:59:59.000Z

268

Radiation source rate estimation through data assimilation of gamma dose rate measurements for operational nuclear emergency response systems  

Science Journals Connector (OSTI)

This paper presents an evaluation of an innovative data assimilation method that has been recently developed in NCSR Demokritos for estimating an unknown emission rate of radionuclides in the atmosphere, with real-scale experimental data. The efficient algorithm is based on the assimilation of gamma dose rate measured data in the Lagrangian atmospheric dispersion model DIPCOT and uses variational principles. The DIPCOT model is used in the framework of the nuclear emergency response system (ERS) RODOS. The evaluation is performed by computational simulations of dispersion of Ar-41 that was emitted routinely by the Australian Nuclear Science and Technology Organisation's (ANSTO) previous research reactor, HIFAR, located in Sydney, Australia. In this paper the algorithm is evaluated against a more complicated case than the others used in previous studies: there was only one monitoring station available each day and the site topography is characterised as moderately complex. Overall the estimated release rate approaches the real one to a very satisfactory degree as revealed by the statistical indicators of errors.

Vasiliki Tsiouri; Spyros Andronopoulos; Ivan Kovalets; Leisa L. Dyer; John G. Bartzis

2012-01-01T23:59:59.000Z

269

National radiation exposures and risks caused by implementing EPA`s proposed revised national primary drinking water regulations  

SciTech Connect (OSTI)

This report estimates risks to workers and the public associated with treatment processes and their associated waste products that would be mandated under proposed regulations of radium, radon, and uranium in drinking water. Three scenarios were examined: (1) all wastes flushed to the sanitary sewer; (2) all wastes disposed on land; (3) similar to (2) but radon removal by granulated activated carbon rather than packed tower aeration. Risks considered included accidental injury and cancer. Worker risks for both scenarios I and II were estimated to be 0.025 and 0.01 deaths per year of operation for radium-226 and radium-228, respectively. Worker risks for uranium were estimated to be 0.13 deaths/year of operation for scenario I and 0.5 deaths/year of operation for scenario II. Worker risks for radon removal were estimated to be 1.7 deaths/year of operation for scenario I and 2.2 deaths/year of operation for scenario II. Risks to the public for scenarios I and II for radium-226 were 4 {times} 10{sup {minus}4} and for radium-228 were 9 {times} 10{sup {minus}5} deaths/year of operation. Risks to the public for scenarios I and II for uranium were 7.3 {times} 10{sup {minus}2} and 2 {times} 10{sup {minus}4}, respectively. Risks to the public for scenario I and II for radon were 24 deaths/year of operation and for scenario III were nil. Public risks were quantified only for people exposed during a year of operation. For example, effects of public exposures in future years via groundwater contamination associated with landfill of treatment waste were not considered.

Morris, S.C.; Rowe, M.D.; Holtzman, S.; Meinhold, A.F.

1993-05-01T23:59:59.000Z

270

Population Studies of Gamma Ray Sources Using Stacking Analysis at Low Galactic Latitudes  

SciTech Connect (OSTI)

We studied the problem of the treatment of uncertainties in the diffuse gamma radiation apparent in stacking analysis of EGRET data at low Galactic latitudes for several classes of sources like PSRs. For those classes of sources we co-added maps of counts, exposure and diffuse background, and residuals, in varying numbers for different sub-categories. Finally we tested for gamma-ray excess emission in those maps and attempt to quantify the systematic biases in such approach. Such kinds of analysis will support and provide confidence in the classification processes of sources and source populations in the GLAST era.

Cillis, Analia N.; /NASA, Goddard; Reimer, Olaf; /Stanford U., HEPL /KIPAC, Menlo Park; Torres, Diego F.; /ICREA, Barcelona /Barcelona, Autonoma U.

2007-11-13T23:59:59.000Z

271

Radiation doses for Marshall Islands Atolls Affected by U.S. Nuclear Testing:All Exposure Pathways, Remedial Measures, and Environmental Loss of 137Cs  

SciTech Connect (OSTI)

The United States conducted 24 nuclear tests at Bikini Atoll with a total yield of 76.8 Megatons (MT). The Castle series produced about 60% of this total and included the Bravo test that was the primary source of contamination of Bikini Island and Rongelap and Utrok Atolls. One of three aerial drops missed the atoll and the second test of the Crossroads series, the Baker test, was an underwater detonation. Of the rest, 17 were on barges on water and 3 were on platforms on an island; they produced most of the contamination of islands at the atoll. There were 42 tests conducted at Enewetak Atoll with a total yield of 31.7 MT (Simon and Robison, 1997; UNSCEAR, 2000). Of these tests, 18 were on a barge over wateror reef, 7 were surface shots, 2 aerial drops, 2 under water detonations, and 13 tower shots on either land or reef. All produced some contamination of various atoll islands. Rongelap Atoll received radioactive fallout as a result of the Bravo test on March 1, 1954 that was part of the Castle series of tests. This deposition was the result of the Bravo test producing a yield of 15 MT, about a factor of three to four greater than the predicted yield that resulted in vaporization of more coral reef and island than expected and in the debris-cloud reaching a much higher altitude than anticipated. High-altitude winds were to the east at the time of detonation and carried the debris-cloud toward Rongelap Atoll. Utrok Atoll also received fallout from the Bravo test but at much lower air and ground-level concentrations than at Rongelap atoll. Other atolls received Bravo fallout at levels below that of Utrok [other common spellings of this island and atoll (Simon, et al., 2009)]. To avoid confusion in reading other literature, this atoll and island are spelled in a variety of ways (Utrik, Utirik, Uterik or Utrok). Dose assessments for Bikini Island at Bikini Atoll (Robison et al., 1997), Enjebi Island at Enewetak Atoll (Robison et al., 1987), Rongelap Island at Rongelap Atoll (Robison et al., 1994; Simon et al., 1997), and Utrok Island at Utrok Atoll (Robison, et al., 1999) indicate that about 95-99% of the total estimated dose to people who may return to live at the atolls today (Utrok Island is populated) is the result of exposure to {sup 137}Cs. External gamma exposure from {sup 137}Cs in the soil accounts for about 10 to 15% of the total dose and {sup 137}Cs ingested during consumption of local food crops such as drinking coconut meat and fluid (Cocos nucifera L.), copra meat and milk, Pandanus fruit, and breadfruit accounts for about 85 to 90%. The other 1 to 2% of the estimated dose is from {sup 90}Sr, {sup 239+240}Pu, and {sup 241}Am. The {sup 90}Sr exposure is primarily through the food chain while the exposure to {sup 239+240}Pu, and {sup 241}Am is primarily via the inhalation pathway as a result of breathing re-suspended soil particles.

Robison, W L; Hamilton, T F

2009-04-20T23:59:59.000Z

272

Gamma-ray binaries  

E-Print Network [OSTI]

Recent observations have shown that some compact stellar binaries radiate the highest energy light in the universe. The challenge has been to determine the nature of the compact object and whether the very high energy gamma-rays are ultimately powered by pulsar winds or relativistic jets. Multiwavelength observations have shown that one of the three gamma-ray binaries known so far, PSR B1259-63, is a neutron star binary and that the very energetic gamma-rays from this source and from another gamma-ray binary, LS I +61 303, may be produced by the interaction of pulsar winds with the wind from the companion star. At this time it is an open question whether the third gamma-ray binary, LS 5039, is also powered by a pulsar wind or a microquasar jet, where relativistic particles in collimated jets would boost the energy of the wind from the stellar companion to TeV energies.

I. F. Mirabel

2006-10-24T23:59:59.000Z

273

Gamma ray burst outflows and afterglows.  

E-Print Network [OSTI]

?? We carry out a theoretical investigation of jet propagation in Gamma Ray Bursts and examine the jitter radiation mechanism as a means of producing… (more)

Morsony, Brian J.

2009-01-01T23:59:59.000Z

274

Assessment of the radiological impact of gamma and radon dose rates at former U mining sites in Central Asia  

Science Journals Connector (OSTI)

An assessment of the radiological situation due to exposure to gamma radiation, radon and thoron was carried out at selected former uranium mining and processing sites in the Central Asian countries of Kazakhstan, Kyrgyzstan, Uzbekistan and Tajikistan. Gamma dose rate measurements were made using various field instruments and radon/thoron measurements were carried out using discriminative radon (222Rn)/thoron (220Rn) solid state nuclear track detectors (SSNTD). The detectors were exposed for an extended period of time, including at least three seasonal periods in a year, in different outdoor and indoor public and residential environments at the selected uranium legacy sites. The results showed that gamma, Rn and Tn doses were in general low, which consequently implies a low/relatively low radiological risk. The major radiation hazard is represented by abandoned radioactive filtration material that was being used as insulation by some Minkush residents (Kyrgyzstan) for a longer period of time. Annual radiation doses of several hundred mSv could be received as a consequence of using this material domestically. In addition, the gamma and Rn/Tn dose rates at Digmai, Tajikistan, could reach values of several 10 mSv/a. The doses of ionizing radiation deriving from external radiation (gamma dose rate), indoor radon and thoron with their short-lived progenies in several cases exceeded the recommended annual effective dose threshold level of 10 mSv. At none of the sites investigated did the individual annual effective doses exceed 30 mSv, the internationally recommended value for considering intervention. Current doses of ionizing radiation do not represent a serious hazard to the health of the resident public, but this issue should be adequately addressed to further reduce needless exposure of the resident public to ionizing radiation.

P. Stegnar; I. Shishkov; M. Burkitbayev; B. Tolongutov; M. Yunusov; R. Radyuk; B. Salbu

2013-01-01T23:59:59.000Z

275

EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS  

SciTech Connect (OSTI)

Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Polymeric materials become damaged by exposure over time to ionizing radiation. Despite the limited lifetime, polymers have unique engineering material properties and polymers continue to be used in tritium handling systems. In tritium handling systems, polymers are employed mainly in joining applications such as valve sealing surfaces (eg. Stem tips, valve packing, and O-rings). Because of the continued need to employ polymers in tritium systems, over the past several years, programs at the Savannah River National Laboratory have been studying the effect of tritium on various polymers of interest. In these studies, samples of materials of interest to the SRS Tritium Facilities (ultra-high molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, Teflon{reg_sign}), Vespel{reg_sign} polyimide, and the elastomer ethylene propylene diene monomer (EPDM)) have been exposed in closed containers to tritium gas initially at 1 atmosphere pressure. These studies have demonstrated the degradation of properties when exposed to tritium gas. Also, the radiolytic production of significant amounts of hydrogen has been observed for UHMW-PE and EPDM. The study documented in this report exposes two similar formulations of EPDM elastomer to gamma irradiation in a closed container backfilled with deuterium. Deuterium is chemically identical to protium and tritium, but allows the identification of protium that is radiolytically produced from the samples. The goal of this program is to compare and contrast the response of EPDM exposure to two different types of ionizing radiation in a similar chemical environment.

Clark, E.

2011-09-22T23:59:59.000Z

276

Polymorphisms in Apoptosis- and Proliferation-Related Genes, Ionizing Radiation Exposure, and Risk of Breast Cancer among U.S. Radiologic Technologists  

Science Journals Connector (OSTI)

...radiation and breast cancer dose-response relationship...controls and quantified radiation breast doses in the low-to-moderate range. (Cancer Epidemiol Biomarkers...Breast Cancer|SNPs|Ionizing radiation|Interaction|Radiobiological...

Alice J. Sigurdson; Parveen Bhatti; Michele M. Doody; Michael Hauptmann; Laura Bowen; Steven L. Simon; Robert M. Weinstock; Martha S. Linet; Marvin Rosenstein; Marilyn Stovall; Bruce H. Alexander; Dale L. Preston; Jeffrey P. Struewing; and Preetha Rajaraman

2007-10-01T23:59:59.000Z

277

Gamma ray camera  

DOE Patents [OSTI]

A gamma ray camera for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array.

Perez-Mendez, Victor (Berkeley, CA)

1997-01-01T23:59:59.000Z

278

Gamma ray camera  

DOE Patents [OSTI]

A gamma ray camera is disclosed for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array. 6 figs.

Perez-Mendez, V.

1997-01-21T23:59:59.000Z

279

Gamma Irradiation | ORNL Neutron Sciences  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Gamma Irradiation Gamma Irradiation Gamma Irradiation Facility Gamma irradiation chamber Gamma irradiation chamber. The HFIR Gamma Irradiation Facility is an experimental facility designed to irradiate materials with gamma radiation from spent fuel elements. The facility chamber is stainless steel and is made of 0.065-thick tubing to maximize the internal dimensions of the chamber. This allows for the largest samples possible that can still fit inside the cadmium post of the spent fuel loading station positions. The interior chamber is approximately 3.75 inches inside diameter and accommodates samples up to 25 inches long. There are two configurations for the chamber assembly, with the only difference being the plugs. The uninstrumented configuration has a top plug that is used for installation of the samples, to support the inert gas

280

Testing and Performance Validation of a Sensitive Gamma Ray Camera Designed for Radiation Detection and Decommissioning Measurements in Nuclear Facilities-13044  

SciTech Connect (OSTI)

This paper describes the measurements, testing and performance validation of a sensitive gamma ray camera designed for radiation detection and quantification in the environment and decommissioning and hold-up measurements in nuclear facilities. The instrument, which is known as RadSearch, combines a sensitive and highly collimated LaBr{sub 3} scintillation detector with an optical (video) camera with controllable zoom and focus and a laser range finder in one detector head. The LaBr{sub 3} detector has a typical energy resolution of between 2.5% and 3% at the 662 keV energy of Cs-137 compared to that of NaI detectors with a resolution of typically 7% to 8% at the same energy. At this energy the tungsten shielding of the detector provides a shielding ratio of greater than 900:1 in the forward direction and 100:1 on the sides and from the rear. The detector head is mounted on a pan/tile mechanism with a range of motion of ±180 degrees (pan) and ±90 degrees (tilt) equivalent to 4 ? steradians. The detector head with pan/tilt is normally mounted on a tripod or wheeled cart. It can also be mounted on vehicles or a mobile robot for access to high dose-rate areas and areas with high levels of contamination. Ethernet connects RadSearch to a ruggedized notebook computer from which it is operated and controlled. Power can be supplied either as 24-volts DC from a battery or as 50 volts DC supplied by a small mains (110 or 230 VAC) power supply unit that is co-located with the controlling notebook computer. In this latter case both power and Ethernet are supplied through a single cable that can be up to 80 metres in length. If a local battery supplies power, the unit can be controlled through wireless Ethernet. Both manual operation and automatic scanning of surfaces and objects is available through the software interface on the notebook computer. For each scan element making up a part of an overall scanned area, the unit measures a gamma ray spectrum. Multiple radionuclides may be selected by the operator and will be identified if present. In scanning operation the unit scans a designated region and superimposes over a video image the distribution of measured radioactivity. For the total scanned area or object RadSearch determines the total activity of operator selected radionuclides present and the gamma dose-rate measured at the detector head. Results of hold-up measurements made in a nuclear facility are presented, as are test measurements of point sources distributed arbitrarily on surfaces. These latter results are compared with the results of benchmarked MCNP Monte Carlo calculations. The use of the device for hold-up and decommissioning measurements is validated. (authors)

Mason, John A.; Looman, Marc R.; Poundall, Adam J.; Towner, Antony C.N. [ANTECH, A. N. Technology Ltd., Unit 6, Thames Park, Wallingford, Oxfordshire, OX10 9TA (United Kingdom)] [ANTECH, A. N. Technology Ltd., Unit 6, Thames Park, Wallingford, Oxfordshire, OX10 9TA (United Kingdom); Creed, Richard; Pancake, Daniel [Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States)] [Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States)

2013-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Radiation: Facts, Risks and Realities  

E-Print Network [OSTI]

of Radiation 3 Understanding Radiation Risks 6 Naturally Occurring (Background) Radiation 7 Man-Made Radiation, beta particles and gamma rays. Other types, such as x-rays, can occur naturally or be machine-produced. Scientists have also learned that radiation sources are naturally all around us. Radiation can come from

282

DOE Radiation Records Contacts List  

Broader source: Energy.gov [DOE]

DOE radiation records contact list for individuals to obtain records of occupational exposure directly from a DOE site.

283

Sandia National Laboratories: Research: Facilities: Gamma Irradiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Gamma Irradiation Facility Gamma Irradiation Facility Photo of Gamma Irradiation Facility The Gamma Irradiation Facility (GIF) provides high-fidelity simulation of nuclear radiation environments for materials and component testing. The low-dose irradiation facility also offers an environment for long-duration testing of materials and electronic components. Such testing may take place over a number of months or even years. Research and other activities The single-structure GIF can house a wide variety of gamma irradiation experiments with various test configurations and at different dose and dose rate levels. Radiation fields at the GIF are produced by high-intensity gamma-ray sources. To induce ionizing radiation effects and damage in test objects, the objects are subjected to high-energy photons from gamma-source

284

Definition: Gamma Log | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Gamma Log Jump to: navigation, search Dictionary.png Gamma Log Gamma logging is a method of measuring naturally occurring gamma radiation to characterize the rock or sediment in a borehole or drill hole. It is a wireline logging method used in mining, mineral exploration, water-well drilling, for formation evaluation in oil and gas well drilling and for other related purposes. Different types of rock emit different amounts and different spectra of natural gamma radiation.[1] View on Wikipedia Wikipedia Definition Gamma ray logging is a method of measuring naturally occurring gamma radiation to characterize the rock or sediment in a borehole or drill hole. It is a wireline logging method used in mining, mineral exploration,

285

Standard Test Method for Application of Ionization Chambers to Assess the Low Energy Gamma Component of Cobalt-60 Irradiators Used in Radiation-Hardness Testing of Silicon Electronic Devices  

E-Print Network [OSTI]

1.1 Low energy components in the photon energy spectrum of Co-60 irradiators lead to absorbed dose enhancement effects in the radiation-hardness testing of silicon electronic devices. These low energy components may lead to errors in determining the absorbed dose in a specific device under test. This method covers procedures for the use of a specialized ionization chamber to determine a figure of merit for the relative importance of such effects. It also gives the design and instructions for assembling this chamber. 1.2 This method is applicable to measurements in Co-60 radiation fields where the range of exposure rates is 7 × 10 ?6 to 3 × 10?2 C kg ?1 s?1 (approximately 100 R/h to 100 R/s). For guidance in applying this method to radiation fields where the exposure rate is >100 R/s, see Appendix X1. Note 1—See Terminology E170 for definition of exposure and its units. 1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information onl...

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

286

Plutonium radiation surrogate  

DOE Patents [OSTI]

A self-contained source of gamma-ray and neutron radiation suitable for use as a radiation surrogate for weapons-grade plutonium is described. The source generates a radiation spectrum similar to that of weapons-grade plutonium at 5% energy resolution between 59 and 2614 keV, but contains no special nuclear material and emits little .alpha.-particle radiation. The weapons-grade plutonium radiation surrogate also emits neutrons having fluxes commensurate with the gamma-radiation intensities employed.

Frank, Michael I. (Dublin, CA)

2010-02-02T23:59:59.000Z

287

Radiation.cdr  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

An average American's exposure is about 620 millirems per year from naturally occurring and other sources. Other Factors Background radiation varies with location....

288

WI Radiation Protection  

Broader source: Energy.gov [DOE]

This statute seeks to regulate radioactive materials, to encourage the constructive uses of radiation, and to prohibit and prevent exposure to radiation in amounts which are or may be detrimental...

289

Theoretical study of ionization profiles of molecular clouds near supernova remnants: Tracing the hadronic origin of GeV gamma radiation  

E-Print Network [OSTI]

Context: Since a few years, signatures of supernova remnants associated with molecular clouds have been detected in gamma rays. Whether these gamma rays are generated by cosmic ray electrons or by cosmic ray protons is usually not known. The detection of hadronic ionization signatures in spatial coincidence with gamma ray signatures can help to unambiguously identify supernova remnants as sources of cosmic ray protons. Methods: In order to calculate hadronic signatures from cosmic ray-induced ionization for an examination of the origin of the observed gamma rays, the transport equation for cosmic ray protons propagating in a molecular cloud, including the relevant momentum loss processes, is solved analytically and the proton flux at any position in the cloud is determined. Results: Since the solution of the transport equation is obtained for arbitrary source functions, it can be used for a variety of supernova remnants. The corresponding theoretical ionization rate, as a function of the penetration depth, is...

Schuppan, Florian; Tjus, Julia Becker

2014-01-01T23:59:59.000Z

290

Effects of Substerilization Doses of Co60 Gamma Radiation on the Cold-Storage Life Extension of Shucked Soft-Shelled Clams and Haddock Fillets  

Science Journals Connector (OSTI)

...000 rad of ionizing radiation. In the dose range from 200,000...000 rad of ionizing radiation. In the dose range from 200,000...000 rad of ionizing radiation. Nevertheless...indicate that in the dose range from 400,000...

E. B. Masurovsky; S. A. Goldblith; J. T. R. Nickerson

1963-05-01T23:59:59.000Z

291

Spectroscopy 16 (2002) 121125 121 Synchrotron radiation circular dichroism  

E-Print Network [OSTI]

undamaged even after long periods of exposure in the Synchroton Radiation Circular Dichroism (SRCD) beam [2

Wallace, Bonnie Ann

292

The neutron-gamma Feynman variance to mean approach: gamma detection and total neutron-gamma detection (theory and practice)  

E-Print Network [OSTI]

Two versions of the neutron-gamma variance to mean (Feynman-alpha method or Feynman-Y function) formula for either gamma detection only or total neutron-gamma detection, respectively, are derived and compared in this paper. The new formulas have a particular importance for detectors of either gamma photons or detectors sensitive to both neutron and gamma radiation. If applied to a plastic or liquid scintillation detector, the total neutron-gamma detection Feynman-Y expression corresponds to a situation where no discrimination is made between neutrons and gamma particles. The gamma variance to mean formulas are useful when a detector of only gamma radiation is used or when working with a combined neutron-gamma detector at high count rates. The theoretical derivation is based on the Chapman-Kolmogorov equation with inclusion of general reactions and passage intensities for neutrons and gammas, but with the inclusion of prompt reactions only. A one energy group approximation is considered. The comparison of the two different theories is made by using reaction intensities obtained in MCNPX simulations with a simplified geometry for two scintillation detectors and a 252Cf-source enclosed in a steel container. In addition, the variance to mean ratios, neutron, gamma and total neutron-gamma, are evaluated experimentally for a weak 252Cf neutron-gamma source in a steel container, a 137Cs random gamma source and a 22Na correlated gamma source. Due to the focus being on the possibility of using neutron-gamma variance to mean theories for both reactor and safeguards applications, we limited the present study to the general analytical expressions for Feynman-Y formulas.

Dina Chernikova; Kĺre Axell; Senada Avdic; Imre Pázsit; Anders Nordlund

2015-01-23T23:59:59.000Z

293

The Polyamine Catabolic Enzyme SAT1 Modulates Tumorigenesis and Radiation Response in GBM  

Science Journals Connector (OSTI)

...Introduction Exposure to ionizing radiation is a well-established...moderate to high-dose radiation exposure. Examples include...atomic bomb survivors in Japan, women treated with repeated exposure to radiation from fluoroscopic chest...

Adina Brett-Morris; Bradley M. Wright; Yuji Seo; Vinay Pasupuleti; Junran Zhang; Jun Lu; Raffaella Spina; Eli E. Bar; Maneesh Gujrati; Rebecca Schur; Zheng-Rong Lu; and Scott M. Welford

2014-12-01T23:59:59.000Z

294

Composition for radiation shielding  

DOE Patents [OSTI]

A composition for use as a radiation shield. The shield has a depleted urum core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container.

Kronberg, James W. (Aiken, SC)

1994-01-01T23:59:59.000Z

295

E-Print Network 3.0 - arrbod acute radiation Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

... 5 Summary: to years). Exposure to naturally occurring background radiation is an example of chronic exposure. Acute......

296

E-Print Network 3.0 - acute radiation effects Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

... 5 Summary: to years). Exposure to naturally occurring background radiation is an example of chronic exposure. Acute......

297

Gamma Log | Open Energy Information  

Open Energy Info (EERE)

Gamma Log Gamma Log Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Gamma Log Details Activities (6) Areas (6) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Downhole Techniques Exploration Sub Group: Well Log Techniques Parent Exploration Technique: Well Log Techniques Information Provided by Technique Lithology: provides information on changes in rock type near the wellbore from changes in measured gamma radiation Stratigraphic/Structural: using multiple gamma logs over an area, the depth to the sandstone and shale layers can be correlated over larger areas Hydrological: Thermal: Cost Information Low-End Estimate (USD): 0.2525 centUSD 2.5e-4 kUSD 2.5e-7 MUSD 2.5e-10 TUSD / foot Median Estimate (USD): 0.3838 centUSD

298

X-RAYRICH GAMMA-RAY BURSTS, PHOTOSPHERES, AND VARIABILITY P. Meszaros,1,2  

E-Print Network [OSTI]

X-RAY­RICH GAMMA-RAY BURSTS, PHOTOSPHERES, AND VARIABILITY P. Me´sza´ros,1,2 E. Ramirez-Ruiz,3 M. J of the observational gamma-ray variability-luminosity relation. Subject headings: gamma rays: bursts -- radiation mechanisms: nonthermal 1. INTRODUCTION Gamma-ray burst (GRB) light curves at gamma-ray ener- gies are often

Zhang, Bing

299

The neutron-gamma Feynman variance to mean approach: gamma detection and total neutron-gamma detection (theory and practice)  

E-Print Network [OSTI]

Two versions of the neutron-gamma variance to mean (Feynman-alpha method or Feynman-Y function) formula for either gamma detection only or total neutron-gamma detection, respectively, are derived and compared in this paper. The new formulas have a particular importance for detectors of either gamma photons or detectors sensitive to both neutron and gamma radiation. If applied to a plastic or liquid scintillation detector, the total neutron-gamma detection Feynman-Y expression corresponds to a situation where no discrimination is made between neutrons and gamma particles. The gamma variance to mean formulas are useful when a detector of only gamma radiation is used or when working with a combined neutron-gamma detector at high count rates. The theoretical derivation is based on the Chapman-Kolmogorov equation with inclusion of general reactions and passage intensities for neutrons and gammas, but with the inclusion of prompt reactions only. A one energy group approximation is considered. The comparison of the ...

Chernikova, Dina; Avdic, Senada; Pázsit, Imre; Nordlund, Anders

2014-01-01T23:59:59.000Z

300

Bacterial stress response to environmental radiation relating to the Fukushima radiation discharge event, Japan: Will environmental bacteria alter their antibiotic susceptibility profile?  

Science Journals Connector (OSTI)

Antibiotic resistance in clinical pathogens in humans may be traced back to resistance mechanisms in environmental bacteria and any factors, which are likely to alter (upregulate) resistance in environmental organisms, is of potential and eventual consequence to human pathogens. Furthermore, sublethal doses of gamma radiation to environmental organisms may cause sublethal stress and a selective pressure, which may lead to mutational events that alter the bacterium's susceptibility profile. A gamma (?) radiation simulation experiment was performed to emulate the exposure of four environmental bacteria, including Listeria innocua, Bacillus subtilis, E. coli and Pseudomonas aeruginosa, to levels of radiation in and around Fukushima, Japan, equating to 1, 10 and 100 years equivalence exposure. Alteration to susceptibility to 14 antibiotics was measured as the primary endpoint. There was no significant alteration in the susceptibility of the Gram-positive organisms, whereas both Gram-negative organisms became slightly more susceptible to the antibiotics tested over time. These data indicate that such radiation exposure will not increase the antibiotic resistance profile of these organisms and hence not add to the global public health burden of increased antibiotic resistance in human bacterial pathogens.

Shigeyuki Nakanishi; John E. Moore; Motoo Matsuda; Colin E. Goldsmith; Wilson A. Coulter; Juluri R. Rao

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Low Dose Radiation Research Program: Biologically Based Analysis of Lung  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Biologically Based Analysis of Lung Cancer Incidence in a Large Biologically Based Analysis of Lung Cancer Incidence in a Large Canadian Occupational Cohort with Low-LET Low-dose Radiation Exposure, and Comparison with Japanese Atomic Bomb Survivors. Authors: W.D. Hazelton, D. Krewski, S.H. Moolgavkar Lung cancer incidence is analyzed in a large Canadian National Dose Registry (CNDR) cohort with individual annual dosimetry for low-dose occupational exposure to gamma and tritium radiation using several types of multistage models. The primary analysis utilizes the two-stage clonal expansion model (TSCE), with sensitivity analyses using extensions of this model incorporating additional stages. Characteristic and distinct temporal patterns of risk are found for dose-response affecting early, middle, or late stages of carcinogenesis, e.g., initiation with one or more stages,

302

Effects of Solar UV Radiation on Morphology and Photosynthesis of Filamentous Cyanobacterium Arthrospira platensis  

Science Journals Connector (OSTI)

...time of exposure to solar radiation (E and F). (A and...E and F) daily solar doses during the exposure period...Cyanobacteria growth & development radiation effects ultrastructure Dose-Response Relationship, Radiation Photosynthesis radiation...

Hongyan Wu; Kunshan Gao; Virginia E. Villafańe; Teruo Watanabe; E. Walter Helbling

2005-09-01T23:59:59.000Z

303

Thermoluminescence response of new KClXBr1?X:EuCl3 sintered phosphors exposed to beta and gamma radiation  

Science Journals Connector (OSTI)

......the dosimetric response for samples of...4. Dosimetric response of composition...understand the radiation storage capability of each...thermoluminescence response of KClXBr1-X...calculation of activation energies and frequency factors from glow......

R. Bernal; E. Cruz-Zaragoza; C. Cruz-Vázquez; S. E. Burruel-Ibarra; M. J. Rivera-Flores; M. Barboza-Flores

2006-09-01T23:59:59.000Z

304

Exposure to Ionizing Radiation and Estimate of Secondary Cancers in the Era of High-Speed CT Scanning: Projections From the Medicare Population  

Science Journals Connector (OSTI)

Purpose The aims of this study were to analyze the distribution and amount of ionizing radiation delivered by CT scans in the modern era of high-speed CT and to estimate cancer risk in the elderly, the patient group most frequently imaged using CT scanning. Methods A retrospective cohort study was conducted using Medicare claims spanning 8 years (1998-2005) to assess CT use. The data were analyzed in two 4-year cohorts, 1998 to 2001 (n = 5,267,230) and 2002 to 2005 (n = 5,555,345). The number and types of CT scans each patient received over the 4-year periods were analyzed to determine the percentage of patients exposed to threshold radiation of 50 to 100 mSv (defined as low) and >100 mSv (defined as high). The National Research Council's Biological Effects of Ionizing Radiation VII models were used to estimate the number of radiation-induced cancers. Results CT scans of the head were the most common examinations in both Medicare cohorts, but abdominal imaging delivered the greatest proportion (43% in the first cohort and 40% in the second cohort) of radiation. In the 1998 to 2001 cohort, 42% of Medicare patients underwent CT scans, with 2.2% and 0.5% receiving radiation doses in the low and high ranges, respectively. In the 2002 to 2005 cohort, 50% of Medicare patients received CT scans, with 4.2% and 1.2% receiving doses in the low and high ranges. In the two populations, 1,659 (0.03%) and 2,185 (0.04%) cancers related to ionizing radiation were estimated, respectively. Conclusions Although radiation doses have been increasing along with the increasing reliance on CT scans for diagnosis and therapy, using conservative estimates with worst-case scenario methodology, the authors found that the risk for secondary cancers is low in older adults, the group subjected to the most frequent CT scanning. Trends showing increasing use, however, underscore the importance of monitoring CT utilization and its consequences.

Aabed B. Meer; Pat A. Basu; Laurence C. Baker; Scott W. Atlas

2012-01-01T23:59:59.000Z

305

The Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays,  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays, Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays, PET, and Gamma-rays Douglas Boreham McMaster University Abstract The goal of this project was to investigate low dose ionizing radiation effects associated with exposure to diagnostic computed tomography (CT) or positron emission tomography (PET) scans. Biological effects were evaluated in wild type and Trp53+/- heterozygous females, following in vivo exposure to diagnostic CT (75kVp, 200µ) or PET (18F-FDG) scans. The short term biological effects following CT or PET scans were evaluated in order to understand biological modification of mechanisms, such as DNA repair processes and apoptosis, that might alter long term cancer risk. Corresponding life-time cancer risk studies are in progress. Short-term

306

Solar irradiance changes and photobiological effects at Earth's surface following astrophysical ionizing radiation events  

E-Print Network [OSTI]

Astrophysical ionizing radiation events have been recognized as a potential threat to life on Earth, primarily through depletion of stratospheric ozone and subsequent increase in surface-level solar ultraviolet radiation. Simulations of the atmospheric effects of a variety of events (such as supernovae, gamma-ray bursts, and solar proton events) have been previously published, along with estimates of biological damage at Earth's surface. In this work, we employed the TUV radiative transfer model to expand and improve calculations of surface-level irradiance and biological impacts following an ionizing radiation event. We considered changes in surface-level UVB, UVA, and photosynthetically active radiation (visible light) for clear-sky conditions and fixed aerosol parameter values. We also considered a wide range of biological effects on organisms ranging from humans to phytoplankton. We found that past work overestimated UVB irradiance, but that relative estimates for increase in exposure to DNA damaging radi...

Thomas, Brian C; Snyder, Brock R

2015-01-01T23:59:59.000Z

307

Low Dose Radiation Research Program: Using a Low LET Electron Microbeam to  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

a Low LET Electron Microbeam to Investigate Non-Targeted Effects of a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation William F. Morgan Radiation Oncology Research Laboratory, Pacific Northwest National Laboratory Why this Project? To examine genomic instability and bystander effects as non-targeted effects associated with low dose radiation exposure. Project Goals To provides a robust, reliable, highly sensitive assay for detecting delayed events occurring in cells exposed to low doses of ionizing radiation. Experimental Approach To mimic radiation damage from gamma and x-ray sources, a low-LET electron microbeam that generates energetic electrons has been designed such that high-energy electrons deposit energy in a pre-selected subset of cells leaving neighboring cells unirradiated. Using a novel green fluorescence gene (GFP) reporter assay, a high through

308

Fundamentals of health physics for the radiation-protection officer  

SciTech Connect (OSTI)

The contents of this book on health physics include chapters on properties of radioactive materials, radiation instrumentation, radiation protection programs, radiation survey programs, internal exposure, external exposure, decontamination, selection and design of radiation facilities, transportation of radioactive materials, radioactive waste management, radiation accidents and emergency preparedness, training, record keeping, quality assurance, and appraisal of radiation protection programs. (ACR)

Murphy, B.L.; Traub, R.J.; Gilchrist, R.L.; Mann, J.C.; Munson, L.H.; Carbaugh, E.H.; Baer, J.L.

1983-03-01T23:59:59.000Z

309

Gamma-ray events thunderclouds  

E-Print Network [OSTI]

stage of rocket-triggered lightning #12;The gamma-ray flash occurred at the same time the upward leader radiation is also produced by natural lightning during the stepped leader phase. · Dwyer et al. 2003, 2004 found that x-rays are also produced by triggered lightning dart leaders. · At present, the only viable

California at Berkeley, University of

310

Report to the DOE nuclear data committee. [EV RANGE 10-100; CROSS SECTIONS; PHOTONEUTRONS; NEUTRONS; GAMMA RADIATION; COUPLED CHANNEL THEORY; DIFFERENTIAL CROSS SECTIONS; MEV RANGE 01-10; ; CAPTURE; GAMMA SPECTRA; THERMAL NEUTRONS; COMPUTER CALCULATIONS; DECAY; FISSION PRODUCTS; FISSION YIELD; SHELL MODELS; NUCLEAR DATA COLLECTIONS  

SciTech Connect (OSTI)

Topics covered include: studies of (n, charged particle) reactions with 14 to 15 MeV neutrons; photoneutron cross sections for /sup 15/N; neutron radiative capture; Lane-model analysis of (p,p) and (n,n) scattering on the even tin isotopes; neutron scattering cross sections for /sup 181/Ta, /sup 197/Au, /sup 209/Bi, /sup 232/Th, and /sup 238/U inferred from proton scattering and charge exchange cross sections; neutron-induced fission cross sections of /sup 245/Cm and /sup 242/Am; fission neutron multiplicities for /sup 245/Cm and /sup 242/Am; the transport of 14 MeV neutrons through heavy materials 150 < A < 208; /sup 249/Cm energy levels from measurement of thermal neutron capture gamma rays; /sup 231/Th energy levels from neutron capture gamma ray and conversion electron spectroscopy; new measurements of conversion electron binding energies in berkelium and californium; nuclear level densities; relative importance of statistical vs. valence neutron capture in the mass-90 region; determination of properties of short-lived fission products; fission yield of /sup 87/Br and /sup 137/I from 15 nuclei ranging from /sup 232/Th to /sup 249/Cf; evaluation of charged particle data for the ECPL library; evaluation of secondary charged-particle energy and angular distributions for ENDL; and evaluated nuclear structure libraries derived from the table of isotopes. (GHT)

Struble, G.L.; Haight, R.C.

1981-03-01T23:59:59.000Z

311

Astrophysical S factor for the radiative capture (12)N(p,gamma)(13)O determined from the (14)N((12)N,(13)O)(13)C proton transfer reaction  

E-Print Network [OSTI]

The cross section of the radiative proton capture reaction on the drip line nucleus (12)N was investigated using the asymptotic normalization coefficient (ANC) method. We have used the (14)N((12)N,(13)O)(13)C proton transfer reaction at 12 Me...

Banu, A.; Al-Abdullah, T.; Fu, C.; Gagliardi, Carl A.; McCleskey, M.; Mukhamedzhanov, A. M.; Tabacaru, G.; Trache, L.; Tribble, Robert E.; Zhai, Y.; Carstoiu, F.; Burjan, V.; Kroha, V.

2009-01-01T23:59:59.000Z

312

Molecular Pathways: Targeted ?-Particle Radiation Therapy  

Science Journals Connector (OSTI)

...and profibrotic cytokines. Radiation-induced malignancy can...1-5 Gy). Kyoji Furukawa (Radiation Effect Research Foundation, Hiroshima, Japan) reviewed the Japanese atomic...late effects of ionizing radiation exposure at low/moderate...

Kwamena E. Baidoo; Kwon Yong; and Martin W. Brechbiel

2013-02-01T23:59:59.000Z

313

Resistance of Marine Bacterioneuston to Solar Radiation  

Science Journals Connector (OSTI)

...of Marine Bacterioneuston to Solar Radiation Helene Agogue Fabien...after exposure to simulated solar radiation. Bacterioneuston...estimate of their screening capacity. Appl. Environ. Microbiol...D. P. 2000. Effects of solar UV-B radiation on aquatic...

Hélčne Agogué; Fabien Joux; Ingrid Obernosterer; Philippe Lebaron

2005-09-01T23:59:59.000Z

314

Low Dose Radiation Program: Radiation Biology and the Radiation Research  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (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

315

Evolving Adjustments to External (Gamma) Slope Factors for CERCLA Risk and Dose Assessments - 12290  

SciTech Connect (OSTI)

To model the external exposure pathway in risk and dose assessments of radioactive contamination at Superfund sites, the U.S. Environmental Protection Agency (EPA) uses slope factors (SFs), also known as risk coefficients, and dose conversion factors (DCFs). Without any adjustment these external radiation exposure pathways effectively assumes that an individual is exposed to a source geometry that is effectively an infinite slab. The concept of an 'infinite slab' means that the thickness of the contaminated zone and its aerial extent are so large that it behaves as if it were infinite in its physical dimensions. EPA has been making increasingly complex adjustments to account for the extent of the contamination and its corresponding radiation field to provide more accurate risk and dose assessment modeling when using its calculators. In most instances, the more accurate modeling results derived from these gamma adjustments are less conservative. The notable exception are for some radionuclides in rooms with contaminated walls, ceiling, and floors, and the receptor is in location of the room with the highest amount of radiation exposure, usually the corner of small rooms and the center of large conference rooms. (authors)

Walker, Stuart [U.S. Environmental Protection Agency (United States)

2012-07-01T23:59:59.000Z

316

RADIATION SENSITIVITY & PROCESSING OF DNA DAMAGE FOLLOWING LOW DOSES OF GAMMA-RAY ALPHA PARTICLES & HZE IRRADIATION OF NORMAL DSB REPAIR DEFICIENT CELLS  

SciTech Connect (OSTI)

Non-homologous end joining (NHEJ) predominates in the repair of DNA double strand breaks (DSB) over homologous recombination (HR). NHEJ occurs throughout the cell cycle whereas HR occurs in late S/G2 due to the requirement of a sister chromatid (Rothkamm et al, Mol Cell Biol 23 5706-15 [2003]). To date evidence obtained with DSB repair deficient cells using pulsed-field gel electrophoresis has revealed the major pathway throughout all phases of the cell cycle for processing high dose induced DSBs is NHEJ (Wang et al, Oncogene 20 2212-24 (2001); Pluth et al, Cancer Res. 61 2649-55 [2001]). These findings however were obtained at high doses when on average >> 20-30 DSBs are formed per cell. The contribution of the repair pathways (NHEJ and HR) induced in response to DNA damage during the various phases of the cell cycle may depend upon the dose (the level of initial DSBs) especially since low levels of DSBs are induced at low dose. To date, low dose studies using NHEJ and HR deficient mutants have not been carried out to address this important question with radiations of different quality. The work presented here leads us to suggest that HR plays a relatively minor role in the repair of radiation-induced prompt DSBs. SSBs lead to the induction of DSBs which are associated specifically with S-phase cells consistent with the idea that they are formed at stalled replication forks in which HR plays a major role in repair. That DNA-PKcs is in some way involved in the repair of the precursors to replication-induced DSB remains an open question. Persistent non-DSB oxidative damage also leads to an increase in RAD51 positive DSBs. Both simple and complex non-DSB DNA damage may therefore contribute to indirect DSBs induced by ionising radiation at replication forks.

O'Neil, Peter

2009-05-15T23:59:59.000Z

317

Radiation-Induced Bystander Effects and Relevance to Human Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (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

318

Low Dose Radiation Research Program: Using a Low LET Electron Microbeam to  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Using a Low LET Electron Microbeam to Investigate Non-Targeted Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation Authors: William F. Morgan1 and Marianne B. Sowa2 Institutions: 1Radiation Oncology Research Laboratory, University of Maryland, Baltimore, Maryland; 2Chemical Structure and Dynamics, Pacific Northwest National Laboratory, Richland Washington We have recently installed a low-linear energy transfer (LET) electron microbeam that generates energetic electrons to mimic radiation damage from gamma- and x-ray sources. It has been designed such that high-energy electrons deposit energy in a pre-selected subset of cells, leaving neighboring cells unirradiated (Figure 1). In this way it is possible to examine non-targeted effects associated with low dose radiation exposure,

319

EFFECTS OF TRITIUM EXPOSURE ON UHMW-PE, PTFE, AND VESPEL  

SciTech Connect (OSTI)

Samples of three polymers, Ultra-High Molecular Weight Polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, also known as Teflon{reg_sign}), and Vespel{reg_sign} polyimide were exposed to 1 atmosphere of tritium gas at ambient temperature for varying times up to 2.3 years in closed containers. Sample mass and size measurements (to calculate density), spectra-colorimetry, dynamic mechanical analysis (DMA), and Fourier-transform infrared spectroscopy (FT-IR) were employed to characterize the effects of tritium exposure on these samples. Changes of the tritium exposure gas itself were characterized at the end of exposure by measuring total pressure and by mass spectroscopic analysis of the gas composition. None of the polymers exhibited significant changes of density. The color of initially white UHMW-PE and PTFE dramatically darkened to the eye and the color also significantly changed as measured by colorimetry. The bulk of UHMW-PE darkened just like the external surfaces, however the fracture surface of PTFE appeared white compared to the PTFE external surfaces. The white interior could have been formed while the sample was breaking or could reflect the extra tritium dose at the surface directly from the gas. The dynamic mechanical response of UHMW-PE was typical of radiation effects on polymers- an initial stiffening (increased storage modulus) and reduction of viscous behavior after three months exposure, followed by lowering of the storage modulus after one year exposure and longer. The storage modulus of PTFE increased through about nine months tritium exposure, then the samples became too weak to handle or test using DMA. Characterization of Vespel{reg_sign} using DMA was problematic--sample-to-sample variations were significant and no systematic change with tritium exposure could be discerned. Isotopic exchange and incorporation of tritium into UHMW-PE (exchanging for protium) and into PTFE (exchanging for fluorine) was observed by FT-IR using an attenuated total reflectance method. No significant change in the Vespel{reg_sign} infrared spectrum was observed after three months exposure. Protium significantly pressurized the UHMW-PE containers during exposure to about nine atmospheres (the initial pressure was one atmosphere of tritium). This is consistent with the well-known production of hydrogen by irradiation of polyethylene by ionizing radiation. The total pressure in the PTFE containers decreased, and a mass balance reveals that the observed decrease is consistent with the formation of small amounts of {sup 3}HF, which is condensed at ambient temperature. No significant change of pressure occurred in the Vespel{reg_sign} containers; however the composition of the gas became about 50% protium, showing that Vespel{reg_sign} interacted with the tritium gas atmosphere to some degree. The relative resistance to degradation from tritium exposure is least for PTFE, more for UHMW-PE, and the most for Vespel{reg_sign}, which is consistent with the known relative resistance of these polymers to gamma irradiation. This qualitatively agrees with the concept of equivalent effects for equivalent absorbed doses of radiation damage of polymers. Some of the changes of different polymers are qualitatively similar; however each polymer exhibited unique property changes when exposed to tritium. Information from this study that can be applied to a tritium facility is: (1) the relative resistance to tritium degradation of the three polymers studied is the same as the relative resistance to gamma irradiation in air (so relative rankings of polymer resistance to ionizing radiation can be used as a relative ranking for assessing tritium compatibility and polymer selection); and (2) all three polymers changed the gas atmosphere during tritium exposure--UHMW-PE and Vespel{reg_sign} exposed to tritium formed H{sub 2} gas (UHMW-PE much more so), and PTFE exposed to tritium formed {sup 3}HF. This observation of forming {sup 3}HF supports the general concept of minimizing chlorofluorocarbon polymers in tritium systems.

Clark, E; Kirk Shanahan, K

2006-05-31T23:59:59.000Z

320

Gamma Irradiation Facility at Sandia National Laboratories, Albuquerque, New Mexico. Final environmental assessment  

SciTech Connect (OSTI)

The US Department of Energy (DOE) has prepared an environmental assessment (EA) on the proposed construction and operation of a new Gamma Irradiation Facility (GIF) at Sandia National Laboratories/New Mexico (SNL/NM). This facility is needed to: enhance capabilities to assure technical excellence in nuclear weapon radiation environments testing, component development, and certification; comply with all applicable ES and H safeguards, standards, policies, and regulations; reduce personnel radiological exposure to comply with ALARA limits in accordance with DOE orders and standards; consolidate major gamma ray sources into a central, secured area; and reduce operational risks associated with operation of the GIF and LICA in their present locations. This proposed action provides for the design, construction, and operation of a new GIF located within TA V and the removal of the existing GIF and Low Intensity Cobalt Array (LICA). The proposed action includes potential demolition of the gamma shield walls and removal of equipment in the existing GIF and LICA. The shielding pool used by the existing GIF will remain as part of the ACRR facility. Transportation of the existing {sup 60}Co sources from the existing LICA and GIF to the new facility is also included in the proposed action. Relocation of the gamma sources to the new GIF will be accomplished by similar techniques to those used to install the sources originally.

NONE

1995-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Mammalian Tissue Response to Low Dose Ionizing Radiation: The Role of Oxidative Metabolism and Intercellular Communication  

SciTech Connect (OSTI)

The objective of the project was to elucidate the mechanisms underlying the biological effects of low dose/low dose rate ionizing radiation in organs/tissues of irradiated mice that differ in their susceptibility to ionizing radiation, and in human cells grown under conditions that mimic the natural in vivo environment. The focus was on the effects of sparsely ionizing cesium-137 gamma rays and the role of oxidative metabolism and intercellular communication in these effects. Four Specific Aims were proposed. The integrated outcome of the experiments performed to investigate these aims has been significant towards developing a scientific basis to more accurately estimate human health risks from exposures to low doses ionizing radiation. By understanding the biochemical and molecular changes induced by low dose radiation, several novel markers associated with mitochondrial functions were identified, which has opened new avenues to investigate metabolic processes that may be affected by such exposure. In particular, a sensitive biomarker that is differentially modulated by low and high dose gamma rays was discovered.

Azzam, Edouard I

2013-01-16T23:59:59.000Z

322

GammaCam Technology Demonstration at ORNL Buildings 3026C and 3026D  

Broader source: Energy.gov [DOE]

The GammaCam system is an effective tool for remotely identifying high gamma radiation in radioactive environments.  Its versatility allows the user to perform preliminary characterization of an...

323

Improved Radiation Dosimetry/Risk Estimates to Facilitate Environmental Management of Plutonium-Contaminated Sites  

SciTech Connect (OSTI)

This report summarizes 4 years of research achievements in this Office of Science (BER), U.S. Department of Energy (DOE) project. The research described was conducted by scientists and supporting staff at Lovelace Respiratory Research Institute (LRRI)/Lovelace Biomedical and Environmental Research Institute (LBERI) and the Southern Urals Biophysics Institute (SUBI). All project objectives and goals were achieved. A major focus was on obtaining improved cancer risk estimates for exposure via inhalation to plutonium (Pu) isotopes in the workplace (DOE radiation workers) and environment (public exposures to Pu-contaminated soil). A major finding was that low doses and dose rates of gamma rays can significantly suppress cancer induction by alpha radiation from inhaled Pu isotopes. The suppression relates to stimulation of the body's natural defenses, including immunity against cancer cells and selective apoptosis which removes precancerous and other aberrant cells.

Scott, Bobby R.; Tokarskaya, Zoya B.; Zhuntova, Galina V.; Osovets, Sergey V.; Syrchikov, Victor A., Belyaeva, Zinaida D.

2007-12-14T23:59:59.000Z

324

Gamma-Ray Bursts, Ultra High Energy Cosmic Rays, and Cosmic Gamma-Ray Background  

E-Print Network [OSTI]

We argue that gamma-ray bursts (GRBs) may be the origin of the cosmic gamma-ray background radiation observed in GeV range. It has theoretically been discussed that protons may carry a much larger amount of energy than electrons in GRBs, and this large energy can be radiated in TeV range by synchrotron radiation of ultra-high-energy protons (\\sim 10^{20} eV). The possible detection of GRBs above 10 TeV suggested by the Tibet and HEGRA groups also supports this idea. If this is the case, most of TeV gamma-rays from GRBs are absorbed in intergalactic fields and eventually form GeV gamma-ray background, whose flux is in good agreement with the recent observation.

Tomonori Totani

1998-10-14T23:59:59.000Z

325

RAPID TeV GAMMA-RAY FLARING OF BL LACERTAE  

SciTech Connect (OSTI)

We report on the detection of a very rapid TeV gamma-ray flare from BL Lacertae on 2011 June 28 with the Very Energetic Radiation Imaging Telescope Array System (VERITAS). The flaring activity was observed during a 34.6 minute exposure, when the integral flux above 200 GeV reached (3.4 {+-} 0.6) Multiplication-Sign 10{sup -6} photons m{sup -2} s{sup -1}, roughly 125% of the Crab Nebula flux measured by VERITAS. The light curve indicates that the observations missed the rising phase of the flare but covered a significant portion of the decaying phase. The exponential decay time was determined to be 13 {+-} 4 minutes, making it one of the most rapid gamma-ray flares seen from a TeV blazar. The gamma-ray spectrum of BL Lacertae during the flare was soft, with a photon index of 3.6 {+-} 0.4, which is in agreement with the measurement made previously by MAGIC in a lower flaring state. Contemporaneous radio observations of the source with the Very Long Baseline Array revealed the emergence of a new, superluminal component from the core around the time of the TeV gamma-ray flare, accompanied by changes in the optical polarization angle. Changes in flux also appear to have occurred at optical, UV, and GeV gamma-ray wavelengths at the time of the flare, although they are difficult to quantify precisely due to sparse coverage. A strong flare was seen at radio wavelengths roughly four months later, which might be related to the gamma-ray flaring activities. We discuss the implications of these multiwavelength results.

Arlen, T. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)] [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Aune, T.; Bouvier, A. [Santa Cruz Institute for Particle Physics and Department of Physics, University of California, Santa Cruz, CA 95064 (United States)] [Santa Cruz Institute for Particle Physics and Department of Physics, University of California, Santa Cruz, CA 95064 (United States); Beilicke, M.; Buckley, J. H.; Bugaev, V.; Dickherber, R. [Department of Physics, Washington University, St. Louis, MO 63130 (United States)] [Department of Physics, Washington University, St. Louis, MO 63130 (United States); Benbow, W. [Fred Lawrence Whipple Observatory, Harvard-Smithsonian Center for Astrophysics, Amado, AZ 85645 (United States)] [Fred Lawrence Whipple Observatory, Harvard-Smithsonian Center for Astrophysics, Amado, AZ 85645 (United States); Cesarini, A.; Connolly, M. P. [School of Physics, National University of Ireland Galway, University Road, Galway (Ireland)] [School of Physics, National University of Ireland Galway, University Road, Galway (Ireland); Ciupik, L. [Astronomy Department, Adler Planetarium and Astronomy Museum, Chicago, IL 60605 (United States)] [Astronomy Department, Adler Planetarium and Astronomy Museum, Chicago, IL 60605 (United States); Cui, W.; Feng, Q.; Finley, J. P. [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States)] [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States); Dumm, J.; Fortson, L. [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)] [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Errando, M. [Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027 (United States)] [Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027 (United States); Falcone, A. [Department of Astronomy and Astrophysics, 525 Davey Lab, Pennsylvania State University, University Park, PA 16802 (United States)] [Department of Astronomy and Astrophysics, 525 Davey Lab, Pennsylvania State University, University Park, PA 16802 (United States); Federici, S. [DESY, Platanenallee 6, D-15738 Zeuthen (Germany)] [DESY, Platanenallee 6, D-15738 Zeuthen (Germany); Finnegan, G., E-mail: qfeng@purdue.edu, E-mail: cui@purdue.edu [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Collaboration: VERITAS Collaboration; and others

2013-01-10T23:59:59.000Z

326

Safety Around Sources of Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Keeping Exposure Low Keeping Exposure Low Working Safely Around Radioactive Contamination Types of Radiation Exposure Managing Radiation Emergencies Procedure Demonstration Is it safe to be around sources? Too much radiation exposure is harmful. The degree of radiation injury depends on the amount of radiation received and the time involved. In general, the higher the amount, the greater the severity of early effects (occurring within a few weeks) and the greater the possibility of late effects such as cancer. The BEIR V (Biological Effects of Ionizing Radiation) Committee of the National Research Council estimates that among 100,000 people exposed to a one-time dose of 10 rem (10,000 mrem) and followed over their life span, about 790 more would die of cancer than the estimated 20,000 cancer deaths that would be expected among a non-exposed group of the same size. NOTE: 10 rem = 100 millisieverts (100 mSv).

327

Harnessing a radiation inducible promoter of Deinococcus radiodurans for enhanced precipitation of uranium  

Science Journals Connector (OSTI)

Abstract Bioremediation is an attractive option for the treatment of radioactive waste. We provide a proof of principle for augmentation of uranium bioprecipitation using the radiation inducible promoter, Pssb from Deinococcus radiodurans. Recombinant cells of D. radiodurans carrying acid phosphatase gene, phoN under the regulation of Pssb when exposed to 7 kGy gamma radiation at two different dose rates of 56.8 Gy/min and 4 Gy/min, showed 8–9 fold increase in acid phosphatase activity. Highest whole cell PhoN activity was obtained after 2 h in post irradiation recovery following 8 kGy of high dose rate radiation. Such cells showed faster removal of high concentrations of uranium than recombinant cells expressing PhoN under a radiation non-inducible deinococcal promoter, PgroESL and could precipitate uranium even after continuous exposure to 0.6 Gy/min gamma radiation for 10 days. Radiation induced recombinant D. radiodurans cells when lyophilized retained high levels of PhoN activity and precipitated uranium efficiently. These results highlight the importance of using a suitable promoter for removal of radionuclides from solution.

Chitra Seetharam Misra; Rita Mukhopadhyaya; Shree Kumar Apte

2014-01-01T23:59:59.000Z

328

radiation.cdr  

Office of Legacy Management (LM)

Radiation-It's a Fact of Life Radiation-It's a Fact of Life It has been with us since the beginning of time. Everyone who has ever walked on this planet has been exposed to radiation. For the most part, nature is the largest source of exposure. It's in the air we breathe, the ground we walk on, and even the food we eat. The radiation we receive from all natural and some man-made sources is called "background radiation." The millirem (mrem) is a unit used for measuring radiation received by a person. The total average background for radiation received by people living in the United States is 360 millirem per year (mrem/yr), of which 300 mrem/yr is from natural sources, and 60 mrem/yr is man-made. Cosmic Radiation from the sun and stars Internal Radiation from naturally radioactive

329

Gamma Ray Burst and Soft Gamma Repeaters. Spinning, Precessing Gamma Jets  

E-Print Network [OSTI]

Gamma Ray Bursts as recent GRB990123 and GRB990510 are observed to occur in cosmic volumes with a corresponding output reaching, for isotropic explosions, energies as large as two solar masses annihilation. These energies are underestimated because of the neglected role of comparable ejected neutrinos bursts. These extreme power cannot be explained with any standard spherically symmetric Fireball model. A too heavy black hole or Star would be unable to coexist with the shortest millisecond time structure of Gamma ray Burst. Beaming of the gamma radiation may overcome the energy puzzle. However any mild explosive beam $(\\Omega > 10^{-2})$ should not solve the jet containment at those disruptive energies. Only extreme beaming $(\\Omega < 10^{-8})$, by a slow decaying, but long-lived precessing jet, it may coexist with characteristic Supernova energies, apparent GRBs output, statistics as well as their connection with older and nearer SGRs relics.

Daniele Fargion

1999-06-28T23:59:59.000Z

330

Composition for radiation shielding  

DOE Patents [OSTI]

A composition for use as a radiation shield is disclosed. The shield has a depleted uranium core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container. 2 figs.

Kronberg, J.W.

1994-08-02T23:59:59.000Z

331

Non-destructive method for determining neutron exposure  

DOE Patents [OSTI]

A non-destructive method for determination of neutron exposure in an object, such as a reactor pressure vessel, is based on the observation of characteristic gamma-rays emitted by activation products in the object by using a unique continuous gamma-ray spectrometer. The spectrometer views the object through appropriate collimators to determine the absolute emission rate of these characteristic gamma-rays, thereby ascertaining the absolute activity of given activation products in the object. These data can then be used to deduce the spatial and angular dependence of neutron exposure at regions of interest within the object.

Gold, R.; McElroy, W.N.

1983-11-01T23:59:59.000Z

332

EFFECTS OF TRITIUM GAS EXPOSURE ON ELECTRICALLY CONDUCTING POLYMERS  

SciTech Connect (OSTI)

Effects of beta (tritium) and gamma irradiation on the surface electrical conductivity of two types of conducting polymer films are documented to determine their potential use as a sensing and surveillance device for the tritium facility. It was shown that surface conductivity was significantly reduced by irradiation with both gamma and tritium gas. In order to compare the results from the two radiation sources, an approximate dose equivalence was calculated. The materials were also sensitive to small radiation doses (<10{sup 5} rad), showing that there is a measurable response to relatively small total doses of tritium gas. Spectroscopy was also used to confirm the mechanism by which this sensing device would operate in order to calibrate this sensor for potential use. It was determined that one material (polyaniline) was very sensitive to oxidation while the other material (PEDOT-PSS) was not. However, polyaniline provided the best response as a sensing material, and it is suggested that an oxygen-impermeable, radiation-transparent coating be applied to this material for future device prototype fabrication. A great deal of interest has developed in recent years in the area of conducting polymers due to the high levels of conductivity that can be achieved, some comparable to that of metals [Gerard 2002]. Additionally, the desirable physical and chemical properties of a polymer are retained and can be exploited for various applications, including light emitting diodes (LED), anti-static packaging, electronic coatings, and sensors. The electron transfer mechanism is generally accepted as one of electron 'hopping' through delocalized electrons in the conjugated backbone, although other mechanisms have been proposed based on the type of polymer and dopant [Inzelt 2000, Gerard 2002]. The conducting polymer polyaniline (PANi) is of particular interest because there are extensive studies on the modulation of the conductivity by changing either the oxidation state of the main backbone chain, or by protonation of the imine groups [de Acevedo, 1999]. There are several types of radiation sensors commercially available, including ionization chambers, geiger counters, proportional counters, scintillators and solid state detectors. Each type has advantages, although many of these sensors require expensive electronics for signal amplification, are large and bulky, have limited battery life or require expensive materials for fabrication. A radiation sensor constructed of a polymeric material could be flexible, light, and the geometry designed to suit the application. Very simple and inexpensive electronics would be necessary to measure the change in conductivity with exposure to radiation and provide an alarm system when a set change of conductivity occurs in the sensor that corresponds to a predetermined radiation dose having been absorbed by the polymer. The advantages of using a polymeric sensor of this type rather than those currently in use are the flexibility of sensor geometry and relatively low cost. It is anticipated that these sensors can be made small enough for glovebox applications or have the ability to monitor the air tritium levels in places where a traditional monitor cannot be placed. There have been a few studies on the changes in conductivity of polyaniline specifically for radiation detection [de Acevedo, 1999; Lima Pacheco, 2003], but there have been no reports on the effects of tritium (beta radiation) on conducting polymers, such as polyaniline or polythiophene. The direct implementation of conducting polymers as radiation sensor materials has not yet been commercialized due to differing responses with total dose, dose rate, etc. Some have reported a large increase in the surface conductivity with radiation dose while others report a marked decrease in conductive properties; these differing observations may reflect the competing mechanisms of chain scission and cross-linking. However, it is clear that the radiation dose effects on conducting polymers must be fully understood before these materials can be used

Kane, M.; Clark, E.; Lascola, R.

2009-12-16T23:59:59.000Z

333

Curcumin Regulates Low-Linear Energy Transfer {gamma}-Radiation-Induced NF{kappa}B-Dependent Telomerase Activity in Human Neuroblastoma Cells  

SciTech Connect (OSTI)

Purpose: We recently reported that curcumin attenuates ionizing radiation (IR)-induced survival signaling and proliferation in human neuroblastoma cells. Also, in the endothelial system, we have demonstrated that NF{kappa}B regulates IR-induced telomerase activity (TA). Accordingly, we investigated the effect of curcumin in inhibiting IR-induced NF{kappa}B-dependent hTERT transcription, TA, and cell survival in neuroblastoma cells. Methods and Materials: SK-N-MC or SH-SY5Y cells exposed to IR and treated with curcumin (10-100 nM) with or without IR were harvested after 1 h through 24 h. NF{kappa}B-dependent regulation was investigated either by luciferase reporter assays using pNF{kappa}B-, pGL3-354-, pGL3-347-, or pUSE-I{kappa}B{alpha}-Luc, p50/p65, or RelA siRNA-transfected cells. NF{kappa}B activity was analyzed using an electrophoretic mobility shift assay and hTERT expression using the quantitative polymerase chain reaction. TA was determined using the telomerase repeat amplification protocol assay and cell survival using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltertrazolium bromide and clonogenic assay. Results: Curcumin profoundly inhibited IR-induced NF{kappa}B. Consequently, curcumin significantly inhibited IR-induced TA and hTERT mRNA at all points investigated. Furthermore, IR-induced TA is regulated at the transcriptional level by triggering telomerase reverse transcriptase (TERT) promoter activation. Moreover, NF{kappa}B becomes functionally activated after IR and mediates TA upregulation by binding to the {kappa}B-binding region in the promoter region of the TERT gene. Consistently, elimination of the NF{kappa}B-recognition site on the telomerase promoter or inhibition of NF{kappa}B by the I{kappa}B{alpha} mutant compromises IR-induced telomerase promoter activation. Significantly, curcumin inhibited IR-induced TERT transcription. Consequently, curcumin inhibited hTERT mRNA and TA in NF{kappa}B overexpressed cells. Furthermore, curcumin enhanced the IR-induced inhibition of cell survival. Conclusions: These results strongly suggest that curcumin inhibits IR-induced TA in an NF{kappa}B dependent manner in human neuroblastoma cells.

Aravindan, Natarajan, E-mail: naravind@ouhsc.ed [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Veeraraghavan, Jamunarani; Madhusoodhanan, Rakhesh; Herman, Terence S. [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Natarajan, Mohan [Department of Otolaryngology, Head and Neck Surgery, University of Texas Health Sciences Center at San Antonio, San Antonio, TX (United States)

2011-03-15T23:59:59.000Z

334

Gamma Ray Bursts  

E-Print Network [OSTI]

Olson. “Observations of gamma-ray bursts of cosmic origin. ”E. Lingenfelter. “Gamma-ray bursts. ” Annual Review of652-654. Waxman, Eli. “Gamma-ray-burst afterglow: supporting

Stahl, Bennett

2014-01-01T23:59:59.000Z

335

Novel Ways to Probe the Universe with Gamma-Ray Bursts and Quasars  

Science Journals Connector (OSTI)

I consider novel ways by which Gamma-Ray Bursts (GRBs) and quasars can be used... $\\alpha$ radiation which probes the neutral in...

Abraham Loeb

2002-01-01T23:59:59.000Z

336

Low Dose Radiation Program: Links - Agencies with Radiation Regulatory  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (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)

337

Radiation Machines and Radioactive Materials (Iowa)  

Broader source: Energy.gov [DOE]

These chapters describe general provisions and regulatory requirements; registration, licensure, and transportation of radioactive materials; and exposure standards for radiation protection.

338

Health effects models for nuclear power plant accident consequence analysis. Modification of models resulting from addition of effects of exposure to alpha-emitting radionuclides: Revision 1, Part 2, Scientific bases for health effects models, Addendum 2  

SciTech Connect (OSTI)

The Nuclear Regulatory Commission (NRC) has sponsored several studies to identify and quantify, through the use of models, the potential health effects of accidental releases of radionuclides from nuclear power plants. The Reactor Safety Study provided the basis for most of the earlier estimates related to these health effects. Subsequent efforts by NRC-supported groups resulted in improved health effects models that were published in the report entitled {open_quotes}Health Effects Models for Nuclear Power Plant Consequence Analysis{close_quotes}, NUREG/CR-4214, 1985 and revised further in the 1989 report NUREG/CR-4214, Rev. 1, Part 2. The health effects models presented in the 1989 NUREG/CR-4214 report were developed for exposure to low-linear energy transfer (LET) (beta and gamma) radiation based on the best scientific information available at that time. Since the 1989 report was published, two addenda to that report have been prepared to (1) incorporate other scientific information related to low-LET health effects models and (2) extend the models to consider the possible health consequences of the addition of alpha-emitting radionuclides to the exposure source term. The first addendum report, entitled {open_quotes}Health Effects Models for Nuclear Power Plant Accident Consequence Analysis, Modifications of Models Resulting from Recent Reports on Health Effects of Ionizing Radiation, Low LET Radiation, Part 2: Scientific Bases for Health Effects Models,{close_quotes} was published in 1991 as NUREG/CR-4214, Rev. 1, Part 2, Addendum 1. This second addendum addresses the possibility that some fraction of the accident source term from an operating nuclear power plant comprises alpha-emitting radionuclides. Consideration of chronic high-LET exposure from alpha radiation as well as acute and chronic exposure to low-LET beta and gamma radiations is a reasonable extension of the health effects model.

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)

1993-05-01T23:59:59.000Z

339

Targeted and Nontargeted Effects of Low-Dose Ionizing Radiation on Delayed Genomic Instability in Human Cells  

Science Journals Connector (OSTI)

...humans receive some radiation exposure, mostly...risks associated with radiation exposure come from populations exposed to ionizing radiation, primarily from epidemiologic...However, those doses, in the range of 0.2 to 2.5...

Lei Huang; Perry M. Kim; Jac A. Nickoloff; and William F. Morgan

2007-02-01T23:59:59.000Z

340

Low Dose Radiation Research Program: DNA Damage in Acutely Irradiated F2  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

DNA Damage in Acutely Irradiated F2 Mice with a History of Paternal DNA Damage in Acutely Irradiated F2 Mice with a History of Paternal F0 Germline Irradiation Authors: J.E. Baulch and O.G. Raabe Institutions: Center for Health and the Environment, University of California, Davis, CA. The main goal of this grant is to evaluate heritable, transgenerational effects of low dose, low-linear-energy-transfer (LET) radiation (0.1 Gy attenuated 137Cs gamma rays) on Type B spermatogonia in 129SVE mice; wild-type and heterozygous for Ataxia-telangiectasia (AT). The ATM heterozygotes are carriers for a genetic mutation (AT mutated, ATM) that is thought to predispose both humans and mice to radiation sensitivity. Experiments conducted in our laboratory have demonstrated heritable effects of paternal germline exposure to ionizing radiation in mice using 1.0 Gy of

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341

Revised analyses of decommissioning for the reference boiling water reactor power station. Effects of current regulatory and other considerations on the financial assurance requirements of the decommissioning rule and on estimates of occupational radiation exposure - appendices. Final report  

SciTech Connect (OSTI)

The NRC staff is in need of decommissioning bases documentation that will assist them in assessing the adequacy of the licensee submittals, from the viewpoint of both the planned actions, including occupational radiation exposure, and the probable costs. The purpose of this reevaluation study is to update the needed bases documentation. This report presents the results of a review and reevaluation of the PNL 1980 decommissioning study of the Washington Public Power Supply System`s Washington Nuclear Plant Two (WNP-2) located at Richland, Washington, including all identifiable factors and cost assumptions which contribute significantly to the total cost of decommissioning the plant for the DECON, SAFSTOR, and ENTOMB decommissioning alternatives. These alternatives now include an initial 5-7 year period during which time the spent fuel is stored in the spent fuel pool prior to beginning major disassembly or extended safe storage of the plant. Included for information (but not presently part of the license termination cost) is an estimate of the cost to demolish the decontaminated and clear structures on the site and to restore the site to a {open_quotes}green field{close_quotes} condition. This report also includes consideration of the NRC requirement that decontamination and decommissioning activities leading to termination of the nuclear license be completed within 60 years of final reactor shutdown, consideration of packaging and disposal requirements for materials whose radionuclide concentrations exceed the limits for Class C low-level waste (i.e., Greater-Than-Class C), and reflects 1993 costs for labor, materials, transport, and disposal activities. Sensitivity of the total license termination cost to the disposal costs at different low-level radioactive waste disposal sites, to different depths of contaminated concrete surface removal within the facilities, and to different transport distances is also examined.

Smith, R.I.; Bierschbach, M.C.; Konzek, G.J.; McDuffie, P.N.

1996-07-01T23:59:59.000Z

342

Solar UV radiation reduces the barrier function of human skin  

Science Journals Connector (OSTI)

Solar UV radiation reduces the barrier function...Stanford, CA 94305 The ubiquitous presence of solar UV radiation in human life is essential for...defense against environmental exposures like solar UV radiation, and its effects on UV targets...

Krysta Biniek; Kemal Levi; Reinhold H. Dauskardt

2012-01-01T23:59:59.000Z

343

Ionizing Radiation Activates the Nrf2 Antioxidant Response  

Science Journals Connector (OSTI)

...Scientific). Results Ionizing radiation does not activate ARE-reporter...determine if exposure to varying doses of ionizing radiation would activate the Nrf2-ARE pathway. The radiation dose range was extended below that used...

J. Tyson McDonald; Kwanghee Kim; Andrew J. Norris; Erina Vlashi; Tiffany M. Phillips; Chann Lagadec; Lorenza Della Donna; Josephine Ratikan; Heather Szelag; Lynn Hlatky; and William H. McBride

2010-11-01T23:59:59.000Z

344

GammaSense: Infrastructureless Positioning Using Background Radioactivity  

Science Journals Connector (OSTI)

We introduce the harvesting of natural background radioactivity for positioning. Using a standard Geiger-Müller counter as sensor, we fingerprint the natural levels of gamma radiation with the aim of then roughly pinpointing the position of a client ...

Doina Bucur; Mikkel Baun Kjćrgaard

2008-10-01T23:59:59.000Z

345

Gamma–ray bursts  

Science Journals Connector (OSTI)

...R. Priest and N. O. Weiss Gamma-ray bursts Martin J. Rees Institute of...Road, Cambridge CB3 0HA, UK Gamma-ray bursts, an enigma for more than 25...gamma-rays|neutron stars| Gamma-ray bursts By Martin J. Rees Institute...

2000-01-01T23:59:59.000Z

346

2013 DOE Occupational Radiation Exposure Report Appendices  

Office of Environmental Management (EM)

Name Year Reported * 6202304 LATAParralax Portsmouth LLC Princeton Plasma Physics Laboratory 1005003 Princeton Plasma Physics Laboratory ...

347

DOE 2012 Occupational Radiation Exposure Report  

Office of Environmental Management (EM)

changed as a result of adopting ICRP 60 dosimetry system; u Used the ICRP 68 dose conversion factors to determine values for the derived air concentrations (DACs); and u Adopted...

348

Radiation Exposure Monitoring Systems - Other Related Sites ...  

Office of Environmental Management (EM)

Other Related Sites DOE - Main Home Page - the home page for all DOE information and web sites. DOE EHSS Information Portal - source for EHSS information across the complex....

349

Time encoded radiation imaging  

DOE Patents [OSTI]

The various technologies presented herein relate to detecting nuclear material at a large stand-off distance. An imaging system is presented which can detect nuclear material by utilizing time encoded imaging relating to maximum and minimum radiation particle counts rates. The imaging system is integrated with a data acquisition system that can utilize variations in photon pulse shape to discriminate between neutron and gamma-ray interactions. Modulation in the detected neutron count rates as a function of the angular orientation of the detector due to attenuation of neighboring detectors is utilized to reconstruct the neutron source distribution over 360 degrees around the imaging system. Neutrons (e.g., fast neutrons) and/or gamma-rays are incident upon scintillation material in the imager, the photons generated by the scintillation material are converted to electrical energy from which the respective neutrons/gamma rays can be determined and, accordingly, a direction to, and the location of, a radiation source identified.

Marleau, Peter; Brubaker, Erik; Kiff, Scott

2014-10-21T23:59:59.000Z

350

Gamma ray generator  

DOE Patents [OSTI]

An embodiment of a gamma ray generator includes a neutron generator and a moderator. The moderator is coupled to the neutron generator. The moderator includes a neutron capture material. In operation, the neutron generator produces neutrons and the neutron capture material captures at least some of the neutrons to produces gamma rays. An application of the gamma ray generator is as a source of gamma rays for calibration of gamma ray detectors.

Firestone, Richard B; Reijonen, Jani

2014-05-27T23:59:59.000Z

351

accelerated radiative transfer: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Dominated Outflows Astrophysics (arXiv) Summary: Plasma outflows from gamma-ray bursts (GRB), pulsar winds, relativistic jets, and ultra-intense laser targets radiate...

352

RADIATION EFFECTS ON EPOXY/CARBON FIBER COMPOSITE  

SciTech Connect (OSTI)

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

353

NMIS With Gamma Spectrometry for Attributes of Pu and HEU, Explosives and Chemical Agents  

SciTech Connect (OSTI)

The concept for the system described herein is an active/passive Nuclear Materials Identification System{sup 2} (NMIS) that incorporates gamma ray spectrometry{sup 3}. This incorporation of gamma ray spectrometry would add existing capability into this system. This Multiple Attribute System can determine a wide variety of attributes for Pu and highly enriched uranium (HEU) of which a selected subset could be chosen. This system can be built using commercial off the shelf (COTS) components. NMIS systems are at All-Russian Scientific Research Institute of Experimental Physics (VNIIEF) and Russian Federal Nuclear Center Institute of Technical Physics, (VNIITF) and measurements with Pu have been performed at VNIIEF and analyzed successfully for mass and thickness of Pu. NMIS systems are being used successfully for HEU at the Y-12 National Security Complex. The use of active gamma ray spectrometry for high explosive HE and chemical agent detection is a well known activation analysis technique, and it is incorporated here. This report describes the system, explains the attribute determination methods for fissile materials, discusses technical issues to be resolved, discusses additional development needs, presents a schedule for building from COTS components, and assembly with existing components, and discusses implementation issues such as lack of need for facility modification and low radiation exposure.

Mihalczo, J. T.; Mattingly, J. K.; Mullens, J. A.; Neal, J. S.

2002-05-10T23:59:59.000Z

354

Actively driven thermal radiation shield  

DOE Patents [OSTI]

A thermal radiation shield for cooled portable gamma-ray spectrometers. The thermal radiation shield is located intermediate the vacuum enclosure and detector enclosure, is actively driven, and is useful in reducing the heat load to mechanical cooler and additionally extends the lifetime of the mechanical cooler. The thermal shield is electrically-powered and is particularly useful for portable solid-state gamma-ray detectors or spectrometers that dramatically reduces the cooling power requirements. For example, the operating shield at 260K (40K below room temperature) will decrease the thermal radiation load to the detector by 50%, which makes possible portable battery operation for a mechanically cooled Ge spectrometer.

Madden, Norman W. (Livermore, CA); Cork, Christopher P. (Pleasant Hill, CA); Becker, John A. (Alameda, CA); Knapp, David A. (Livermore, CA)

2002-01-01T23:59:59.000Z

355

Radiation Safety Edward O'Connell  

E-Print Network [OSTI]

tissues) #12;Sources of Background Radiation Exposure · Naturally occurring radioactive materialsRadiation Safety Edward O'Connell Radiation Safety Officer Stony Brook University New York #12;STONY BROOK UNIVERSITY & U. HOSPITAL MEDICAL CENTER #12;Why Radiation Safety · Working with radioactive

356

Web-based tools for quality assurance and radiation protection in diagnostic radiology  

Science Journals Connector (OSTI)

......relating to radiation protection...physicist, radiation safety officer, other...use of any software other than...of the QADDS software package. ACKNOWLEDGEMENTS...exposure to radiation in medical...Radiation safety management......

B. M. Moores; P. Charnock; M. Ward

2010-01-01T23:59:59.000Z

357

Gamma-emitting Materials for Industry  

Science Journals Connector (OSTI)

... , p. 717). A paper dealing with the supply and uses of radium and radon for industry is now being distributed by the Ministry to trade associations, professional institutes ... Points of interest arising from this paper are the different physical properties of radium and radon. Though they both emit gamma-rays of identical quality, the radiation of the former ...

1949-06-04T23:59:59.000Z

358

Gamma Ray Imaging for Environmental Remediation  

SciTech Connect (OSTI)

This program is the development of germanium strip detectors for environmental remediation. It is a collaboration between the Naval Research Laboratory and Lawrence Berkeley National Lab. The goal is to develop detectors that are simultaneously capable of excellent spectroscopy and imaging of gamma radiation.

B.F. Philips; R.A. Kroeger: J.D. Kurfess: W.N. Johnson; E.A. Wulf; E. I. Novikova

2004-11-12T23:59:59.000Z

359

Ultrahigh Energy Cosmic Rays and Prompt TeV Gamma Rays from Gamma Ray Bursts  

E-Print Network [OSTI]

Gamma Ray Bursts (GRBs) have been proposed as one {\\it possible} class of sources of the Ultrahigh Energy Cosmic Ray (UHECR) events observed up to energies $\\gsim10^{20}\\ev$. The synchrotron radiation of the highest energy protons accelerated within the GRB source should produce gamma rays up to TeV energies. Here we briefly discuss the implications on the energetics of the GRB from the point of view of the detectability of the prompt TeV gamma rays of proton-synchrotron origin in GRBs in the up-coming ICECUBE muon detector in the south pole.

Pijushpani Bhattacharjee; Nayantara Gupta

2003-05-12T23:59:59.000Z

360

Did a gamma-ray burst initiate the late Ordovician mass extinction?  

E-Print Network [OSTI]

Did a gamma-ray burst initiate the late Ordovician mass extinction? A.L. Melott1 , B.S. Lieberman2 Abstract: Gamma-ray bursts (GRBs) produce a flux of radiation detectable across the observable Universe words: Population and evolution, mass extinction, gamma-ray burst, Ordovician, ultraviolet ozone

Jackman, Charles H.

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Radiation dose in dental radiology  

Science Journals Connector (OSTI)

...The aim of this study was to compare radiation exposure in panoramic radiography (PR), dental CT, and digital volume tomography (DVT) ... at appropriate locations were exposed as in a dental examination. In PR...

M. Cohnen; J. Kemper; O. Möbes; J. Pawelzik; U. Mödder

2002-03-01T23:59:59.000Z

362

Cataractogenic effects of proton radiation  

E-Print Network [OSTI]

of proton radiation damage. The purpose of this study was (1) to determine the relative cataractogenic effects of different proton en- ergies, (2) to determine the relative cataractogenic effects of different radiation doses and (3) to determine... Laboratory in 1945 and 1946. Ten victims were exposed to various doses of moderately fast neutrons and hard gamma rays. In the eight survivors, two radiation cataracts resulted (15). In 1948 it was reported that five nuclear physicists with a common...

Kyzar, James Ronald

2012-06-07T23:59:59.000Z

363

Fiber fed x-ray/gamma ray imaging apparatus  

DOE Patents [OSTI]

X-ray/gamma ray imaging apparatus is disclosed for detecting the position, energy, and intensity of x-ray/gamma ray radiation comprising scintillation means disposed in the path of such radiation and capable of generating photons in response to such radiation; first photodetection means optically bonded to the scintillation means and capable of generating an electrical signal indicative of the intensity, and energy of the radiation detected by the scintillation means; second photodetection means capable of generating an electrical signal indicative of the position of the radiation in the radiation pattern; and means for optically coupling the scintillation means to the second photodetection means. The photodetection means are electrically connected to control and storage means which may also be used to screen out noise by rejecting a signal from one photodetection means not synchronized to a signal from the other photodetection means; and also to screen out signals from scattered radiation.

Hailey, Charles J. (San Francisco, CA); Ziock, Klaus-Peter (Livermore, CA)

1992-01-01T23:59:59.000Z

364

Angular and Energy Characteristics of Gamma Field at the New Safe Confinement Construction Sit  

SciTech Connect (OSTI)

To results of measurements of angular y and energy distribution of gamma-radiation at the cites of New Safe Confinement erection. The data analysis permitted to identify the main sources of gamma-radiation and to systematize the obtained results.

Batiy, Valeriy; Glebkin, S; Pavlovskiy, L; Pravdyvyi, O; Rudko, Vladimir; Shcherbin, Vladimir; Stojanov, O; Schmieman, Eric A.

2005-08-08T23:59:59.000Z

365

Amelioration of radiation-induced hematopoietic and gastrointestinal damage by Ex-RAD® in mice  

Science Journals Connector (OSTI)

......subsyndrome [5, 6]. Other radiation-countermeasure drugs...gamma-tocotrienol, a naturally occurring vitamin E analog, protected mice from radiation-induced pancytopenia...that protect against radiation-induced hematopoietic...30] in mouse model. Naturally occurring vitamin E......

Sanchita P. Ghosh; Shilpa Kulkarni; Michael W. Perkins; Kevin Hieber; Roli L. Pessu; Kristen Gambles; Manoj Maniar; Tzu-Cheg Kao; Thomas M. Seed; K. Sree Kumar

2012-07-01T23:59:59.000Z

366

Vinflunine (VFL) versus vinorelbine (VRL) and their interaction with radiation in vitro, preliminary results  

Science Journals Connector (OSTI)

...their interaction with radiation in vitro, preliminary...but differs from the naturally occuring compounds in its chemical...between VRL/VFL and radiation, cells were incubated...24h immediately before radiation (Co-60gamma rays...

Cindy Simoens; Filip Lardon; Christel M. De Pooter; Fabienne Breillout; and Jan B. Vermorken

2005-05-01T23:59:59.000Z

367

The whole-body counting facility at the Swedish Radiation Safety Authority after relocation  

Science Journals Connector (OSTI)

......the Swedish Radiation Safety Authority new location...funded by the Swedish Radiation Safety Authority. ACKNOWLEDGMENTS...Measurements of gamma-radiation from the human body...ORTEC. MCA emulator software version 6.0. 2000......

L. del Risco Norrlid; I. Östergren

2011-03-01T23:59:59.000Z

368

Track 3: Exposure Hazards  

Broader source: Energy.gov [DOE]

ISM Workshop Presentations Knoxville Convention Center, Knoxville, TN August 2009 Track 3: Exposure Hazards

369

Observations of cosmic gamma ray sources and their contribution to the diffuse gamma ray background  

SciTech Connect (OSTI)

The objective is to study soft gamma ray emission in the 0.1 to 10 MeV energy band for selected active galactic nuclei and explore how much they contribute to the total diffuse gamma ray background. A series of imaging observations of extragalactic objects in the low energy gamma-ray region were carried out by the Coded Aperture Directional Gamma-ray Telescope (DGT). The DGT was successfully flown at stratospheric balloon altitudes, and observations were made of the Crab, NGC 1275, MKN 421, and NGC 4151. The measured Crab spectrum is consistent with a featureless power-law of the form. Significant emission was detected up to 500 keV from the Seyfert galaxy, NGC 4151. To increase the total sky exposure the extragalactic field images were analyzed, including the 3C 273 region, obtained by the DGT.

Bhattacharya, D.

1990-01-01T23:59:59.000Z

370

Gamma-emitting radionuclides in the shallow marine sediments off the Sindh coast, Arabian Sea  

Science Journals Connector (OSTI)

......Pakistan), the Bay of Bengal(18) and...absorbed gamma radiation outdoor dose rates (D...Norwegian Radiation Protection...estuary and the Bay of Bengal. Health...evaluation of the radiation hazard...Assessment of dose rate and...G. E. Estimation of radiation......

M. Akram; Riffat M. Qureshi; Nasir Ahmad; Tariq Jamal Solaija

2006-07-01T23:59:59.000Z

371

Gamma?ray burst spectroscopy  

Science Journals Connector (OSTI)

The statistics and physical properties of gamma ray burst spectral features are presented following a brief review of early theoretical predictions of and experimental searches for such emission. The ?100 observations of 50 keV absorption and 400 keV emission features constitute the largest data base on neutron star lines. Although the statistical significance of individual observations is often weak and interpretation of these features as cyclotron absorption and annihilation radiation poses some theoretical problems it is clear that future observations may have far?reaching implications.

K. Hurley

1988-01-01T23:59:59.000Z

372

Effect of silver nanoparticle and glycyrrhizic acid (SN-GLY) complex on repair of whole body radiation-induced cellular DNA damage and genomic instability in mice  

Science Journals Connector (OSTI)

Silver nanoparticles (SN) were redispersed in aqueous solution of Pluronic F127 and complexed with the phytoceutical, glycyrrhizic acid (GLY) to obtain SN-GLY complex. The ability of the SN-GLY complex to offer protection against ionising radiation in post-irradiation scenarios was evaluated in ex vivo and in vivo models using Swiss albino mice. Treatment of mouse blood leucocytes with SN-GLY immediately after 4 Gy gamma radiation exposure, ex vivo, enhanced the rate of repair of cellular DNA damages as revealed by comet assay. Exposure of mice to 4 Gy whole body gamma radiation induced formation of strand breaks in cellular DNA and the unrepaired double strand breaks eventually caused the formation of micronuclei. The post-irradiation administration of SN-GLY resulted in a faster decrease in the comet parameters indicating enhanced cellular DNA repair process and reduction in micronucleus formation. Thus the studies showed effective radiation protection by SN-GLY in post-irradiation conditions.

Dhanya K. Chandrasekharan; Cherupally Krishnan Krishnan Nair

2010-01-01T23:59:59.000Z

373

The photonuclear neutron and gamma-ray backgrounds in the fast ignition experiment  

SciTech Connect (OSTI)

In the fast-ignition scheme, very hard x-rays (hereinafter referred to as {gamma}-rays) are generated by Bremsstrahlung radiation from fast electrons. Significant backgrounds were observed around the deuterium-deuterium fusion neutron signals in the experiment in 2010. In this paper the backgrounds were studied in detail, based on Monte Carlo simulations, and they were confirmed to be {gamma}-rays from the target, scattered {gamma}-rays from the experimental bay walls ({gamma}{sup Prime }-rays), and neutrons generated by ({gamma}, n) reactions in either the target vacuum chamber or the diagnostic instruments ({gamma}-n neutrons).

Arikawa, Y.; Nagai, T.; Hosoda, H.; Abe, Y.; Kojima, S.; Fujioka, S.; Sarukura, N.; Nakai, M.; Shiraga, H.; Azechi, H. [Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka Suita (Japan); Ozaki, T. [National Institution Fusion Science, 322-6 Oroshi-cho, Toki-city, Gifu (Japan)

2012-10-15T23:59:59.000Z

374

Effect of surface treatments on radiation buildup in steam generators  

SciTech Connect (OSTI)

Test coupons of typical PWR materials of construction were prepared using a number of pretreatments to minimize radiation buildup. The coupons were then exposed to primary coolant at the Doel-2 PWR in Belgium. The exposure periods for the coupons ranged from one to three fuel cycles. After removal from the primary system, doserate and gamma spectroscopy measurements were made to determine the radioactivity levels on the coupons. Varying levels of success were achieved for the preconditioning techniques tested. Electropolishing alone provided some degree of resistance to radiation buildup on the treated surface and electropolishing plus passivation was shown to be even better. Radiation buildup resistance of the palladium-coated coupons was poor; radiation levels on these coupons were even higher than on the untreated reference coupons. The poor performance of the palladium-coated coupons was possibly due to the method used to apply the coating. In contrast to palladium coating, very encouraging results were achieved with chromium plating plus passivation. Preliminary results show that this technique can inhibit activity deposition by as much as a factor of ten. 4 refs., 64 figs., 26 tabs.

Asay, R.H. (Radiological and Chemical Technology, Inc., Santa Clara, CA (United States)); Pick, M.E. (Nuclear Electric plc, Berkeley (United Kingdom). Berkeley Nuclear Labs.); Roofthooft, R. (Laboratoire Belge de l'Industrie Electrique (LABORELEC), Linkebeek (Belgium)); van Melsen, C. (Energy Invest, Beersel (Belgium))

1991-11-01T23:59:59.000Z

375

Radiation tolerance of piezoelectric bulk single-crystal aluminum nitride  

SciTech Connect (OSTI)

For practical use in harsh radiation environments, we pose selection criteria for piezoelectric materials for nondestructive evaluation (NDE) and material characterization. Using these criteria, piezoelectric aluminum nitride is shown to be an excellent candidate. The results of tests on an aluminumnitride-based transducer operating in a nuclear reactor are also presented. We demonstrate the tolerance of single-crystal piezoelectric aluminum nitride after fast and thermal neutron fluences of 1.85 × 1018 neutron/cm2 and 5.8 × 1018 neutron/cm2, respectively, and a gamma dose of 26.8 MGy. The radiation hardness of AlN is most evident from the unaltered piezoelectric coefficient d33, which measured 5.5 pC/N after a fast and thermal neutron exposure in a nuclear reactor core for over 120 MWh, in agreement with the published literature value. The results offer potential for improving reactor safety and furthering the understanding of radiation effects on materials by enabling structural health monitoring and NDE in spite of the high levels of radiation and high temperatures, which are known to destroy typical commercial ultrasonic transducers.

David A. Parks; Bernhard R. Tittmann

2014-07-01T23:59:59.000Z

376

E-Print Network 3.0 - acute whole-body exposure Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

radiation exposure is expressed in a unit called... of approximatly 360 mrem ... Source: Yucca Mountain Project, US EPA Collection: Environmental Sciences and Ecology 2 Influence...

377

Solid cancer incidence among the Chernobyl emergency workers residing in Russia: estimation of radiation risks  

Science Journals Connector (OSTI)

For the method of radiation dose measurement, the dosimetric data for the studied... 1. Exposure or absorbed dose recorded...

V. K. Ivanov; A. I. Gorski; A. F. Tsyb…

2004-05-01T23:59:59.000Z

378

Gamma-ray burst data from DMSP satellites  

SciTech Connect (OSTI)

A number of gamma-ray bursts have been detected by means of gamma-ray detectors aboard three Air Force Defense Meteorological Satellite Program (DMSP) satellites, in polar orbits at 800 km altitude. The gamma-ray data have a 2-second resolving time, and are usually telemetered in 5 energy bins in the range 50--1000 keV. Although it is not possible to detect gamma-ray bursts when the DMSP satellites are passing through the radiation belt or the South Atlantic Anomaly, or when the source is obscured by the Earth, a number of gamma-ray bursts have been detected by two or even three of the satellites. The DMSP data may be of considerable, assistance in evaluating time histories, locations, and spectra of gamma-ray bursts.

Terrell, J.; Klebesadel, R.W.; Lee, P. (Los Alamos National Lab., NM (United States)); Griffee, J.W. (Sandia National Labs., Albuquerque, NM (United States))

1991-01-01T23:59:59.000Z

379

Gamma-ray burst data from DMSP satellites  

SciTech Connect (OSTI)

A number of gamma-ray bursts have been detected by means of gamma-ray detectors aboard three Air Force Defense Meteorological Satellite Program (DMSP) satellites, in polar orbits at 800 km altitude. The gamma-ray data have a 2-second resolving time, and are usually telemetered in 5 energy bins in the range 50--1000 keV. Although it is not possible to detect gamma-ray bursts when the DMSP satellites are passing through the radiation belt or the South Atlantic Anomaly, or when the source is obscured by the Earth, a number of gamma-ray bursts have been detected by two or even three of the satellites. The DMSP data may be of considerable, assistance in evaluating time histories, locations, and spectra of gamma-ray bursts.

Terrell, J.; Klebesadel, R.W.; Lee, P. [Los Alamos National Lab., NM (United States); Griffee, J.W. [Sandia National Labs., Albuquerque, NM (United States)

1991-12-31T23:59:59.000Z

380

FINAL REPORT EXPOSURE SCENARIOS FOR USE IN  

E-Print Network [OSTI]

FINAL REPORT EXPOSURE SCENARIOS FOR USE IN ESTIMATING RADIATION DOSES TO THE PUBLIC FROM HISTORICAL for use in the estimation of doses to reference individuals due to atmospheric releases of radionuclides). This report was prepared in response to Task 3 of the INEL dose reconstruction study commissioned

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Results of mobile gamma scanning activities in St. Louis, Missouri  

SciTech Connect (OSTI)

From 1942 through approximately 1966, the Mallinckrodt Chemical Works operated four plants in St. Louis, Missouri, for the Manhattan Engineer District and the Atomic Energy Commission. A variety of production processes using uranium- and radium-bearing ore materials were performed at the plants. It is the policy of the DOE to verify that radiological conditions at such sites or facilities comply with current DOE guidelines. Guidelines for release and use of such sites have become more stringent as research has provided more information since previous cleanups. The Formerly Utilized Sites Remedial Action Program (FUSRAP) was established as part of that effort to confirm the closeout status of facilities under contract to agencies preceding DOE during early nuclear energy development. Under the FUSRAP program, the Mallinckrodt properties have been previously investigated to determine the extent of on-site radiological contamination. At the request of DOE, Oak Ridge National Laboratory (ORNL) conducted a survey in May 1990, of public roadways and suspected haul routes between the Mallinckrodt plant and storage sites in St. Louis to ensure that no residual radioactive materials were conveyed off-site. A mobile gamma scanning van with an on-board computer system was used to identify possible anomalies. Suspect areas are those displaying measurements deviating from gamma exposure rates identified as typical for radiologically unenhanced areas in the vicinity of the areas of interest. The instrumentation highlighted three anomaly locations each of which measured less than 1m{sup 2} in size. None of the slightly elevated radiation levels originated from material associated with former AEC-related processing operations in the area. The anomalies resulted from elevated concentrations of radionuclides present in phosphate fertilizers, increased thorium in road-base gravel, and emanations from the radioactive storage site near the Latty Avenue airport. 9 refs., 3 figs.

Rodriguez, R E; Witt, D A; Cottrell, W D; Carrier, R F

1991-06-01T23:59:59.000Z

382

Radiation prevents much cancer  

Science Journals Connector (OSTI)

Evidence reviewed here supports the concept that chronic exposure to ionising radiation can dramatically decrease cancer incidence and mortality. This evidence includes an inverse relationship between radiation levels and cancer induction and/or mortality in: over 200 million people in the USA; 200 million people in India; 10,000 residents of Taipei who live in cobalt-60 contaminated homes; high radiation areas of Ramsar, Iran; 12 million person-years of exposed and carefully selected control nuclear workers; almost 300,000 homes with radon in the USA; non-smokers in high radon areas of Saxony, Germany.

T.D. Luckey

2007-01-01T23:59:59.000Z

383

Gamma-Ray Shielding Effectiveness of Some Alloys for Fusion Reactor Design  

Science Journals Connector (OSTI)

The gamma-ray shielding effectiveness of some oxide dispersion-strengthen (ODS) alloys by means of mass attenuation coefficients, mean free path, exposure buildup factors and energy absorption buildup factors hav...

Vishwanath P. Singh; M. E. Medhat; N. M. Badiger

2014-10-01T23:59:59.000Z

384

Ultraviolet Exposure and Mortality among Women in Sweden  

Science Journals Connector (OSTI)

...questions using detailed data on solar and artificial UV exposure during...843 subjects with a total energy intake outside the 1st and 99th...Risks to Humans Volume 55: Solar and Ultraviolet Radiation...Boscoe FP , Schymura MJ.Solar ultraviolet-B exposure and...

Ling Yang; Marie Lof; Marit Bragelien Veierřd; Sven Sandin; Hans-Olov Adami; and Elisabete Weiderpass

2011-04-01T23:59:59.000Z

385

Low Dose Radiation Research Program: Low-Dose Dose-Response of  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Low-Dose Dose-Response of Proliferating Human Cells Exposed to Low Low-Dose Dose-Response of Proliferating Human Cells Exposed to Low Dose Rate g-Radiation. Authors: Louise Enns,1 Michael Weinfeld,1 Albert Murtha,1 and Kenneth Bogen2 Institutions: 1Cross Cancer Institute and 2Lawrence Livermore National Laboratory. Clinical and environmental exposure to ionizing radiation rarely exceeds 200 cGy. To examine cell proliferation at early times (up to 5 days) post-irradiation, we are utilizing an assay in which single cells encapsulated within ~30- to 70-µm-diameter agarose gel microdrops (GMDs) are exposed and cultured for 4 days at 37°C, then analyzed by flow cytometry (FC). Clonogenic proliferation is measured as the fraction of occupied GMDs containing multicellular microcolonies after 4 days in culture. This assay was applied to human A549 lung cells exposed to gamma

386

Radiation damage in undoped CsI and CsI(Tl)  

SciTech Connect (OSTI)

Radiation damage has been studied in undoped CsI and CsI(TI) crystals using [sup 60]Co gamma radiation for doses up to [approximately] 4.2 [times] 10[sup 6]. Samples from various manufacturers were measured ranging in size from 2.54 cm long cylinders to a 30 cm long block. Measurements were made on the change in optical transmission and scintillation light output as a function of dose. Although some samples showed a small change in transmission, a significant change in light output was observed for all samples. Recovery from damage was also studied as a function of time and exposure to UV light. A short lived phosphorescence was observed in undoped CsI, similar to the phosphorescence seen in CsI(TI).

Woody, C.L.; Kierstead, J.A.; Levy, P.W.; Stoll, S.

1992-01-01T23:59:59.000Z

387

Radiation damage in undoped CsI and CsI(Tl)  

SciTech Connect (OSTI)

Radiation damage has been studied in undoped CsI and CsI(TI) crystals using {sup 60}Co gamma radiation for doses up to {approximately} 4.2 {times} 10{sup 6}. Samples from various manufacturers were measured ranging in size from 2.54 cm long cylinders to a 30 cm long block. Measurements were made on the change in optical transmission and scintillation light output as a function of dose. Although some samples showed a small change in transmission, a significant change in light output was observed for all samples. Recovery from damage was also studied as a function of time and exposure to UV light. A short lived phosphorescence was observed in undoped CsI, similar to the phosphorescence seen in CsI(TI).

Woody, C.L.; Kierstead, J.A.; Levy, P.W.; Stoll, S.

1992-12-01T23:59:59.000Z

388

Los Alamos Lab: Radiation Protection: Annual Occupational Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Annual Occupational Radiation Dosimetry Report Print information on Annual Occupational Radiation Dosimetry Report (pdf). This webpage provides information to help you understand the dose quantities being reported to you on your Annual Occupational Radiation Dosimetry Report. If you would like general information about radiation exposure, please refer to www.radiationanswers.org. Title 10 Code of Federal Regulation Part 835, Occupational Radiation Protection (10 CFR 835), requires assessment, recording and reporting of radiation doses to individuals who are exposed to sources of radiation or radioactive contamination. This includes assessing external exposure from a variety of radiation types, such as, beta, photon, and neutron radiation. External exposures may be uniform over the whole body or occur in a non-uniform (i.e., limited body location) fashion. Internal doses occur when radioactive material is taken into the body through ingestion, inhalation, absorption or wounds. The requirements include assessing doses to the whole body, skin, lens of the eyes, extremities and various organs and tissues.

389

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

SciTech Connect (OSTI)

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

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

1980-01-01T23:59:59.000Z

390

Radiation effects on humans  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (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.

391

Gamma Ray Bursts Sudden, intense flashes of gamma rays  

E-Print Network [OSTI]

Gamma Ray Bursts #12;The Case Sudden, intense flashes of gamma rays come from nowhere and disappear with out a trace. Incredibly powerful: A single gamma ray burst is hundreds of times brighter a supernova #12;Who Vela (1960's) Looking for arms testing, found gamma ray bursts Compton Gamma Ray Observatory

Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group

392

Patterns of cell division, DNA base compositions, and fine structures of some radiation-resistant vegetative bacteria found in food.  

Science Journals Connector (OSTI)

...29. Thornley, M. J. 1963. Radiation resistance among bac- VOL...Glauert. 1968. Fine structure and radiation resistance in Acinetobacter studies...Maxcy. 1971. Impact of low doses of gamma radiation and storage of the microflora...

S W Sanders; R B Maxcy

1979-01-01T23:59:59.000Z

393

The Association between Cancers and Low Level Radiation: an evaluation of the epidemiological evidence at the Hanford Nuclear Weapons Facility  

E-Print Network [OSTI]

indiv. indiv. Gilbertetal. (Hanford & Combined) Gilbertetal.on both radiation and the Hanford facility. The data used toG. Radiation exposures of Hanford workers dying from cancer

Britton, Julie

2010-01-01T23:59:59.000Z

394

Gamma ray burst positrons  

Science Journals Connector (OSTI)

The international network of gamma ray burst detectors has provided redundant localizations for six gamma ray bursts with accuracies in the arcminute range. Catalog radio soft X?ray and optical searches have been performed for some of these events. The results of these searches are reviewed. Although radio X?ray and optical candidates are found in the error boxes no clear association between gamma ray bursts and other forms of emission has emerged to date. Optical radio searches are continuing.

K. Hurley

1982-01-01T23:59:59.000Z

395

Gamma irradiation effects in W films  

SciTech Connect (OSTI)

Using the van Der Pauw methodology, the surface resistivity of irradiated tungsten films deposited on Silicon substrate was measured. The films were exposed to {gamma} radiation using a isotopic {sup 60}Co source in three irradiation stages attaining 40.35 kGy in total dose. The obtained results for superficial resistivity display a time annealing features and their values are proportional to the total dose.

Claro, Luiz H. [Instituto de Estudos Avancados - IEAv, Rod. dos Tamoios, km 5,5, CEP: 12228-840, Sao Jose dos Campos, SP (Brazil) and Faculdade de Tecnologia Sao Francisco - FATESF, Av. Siqueira Campos, 1174, CEP: 12207-000, Jacarei (Brazil); Santos, Ingrid A. [Instituto de Estudos Avancados - IEAv, Rod. dos Tamoios, km 5,5, CEP: 12228-840, Sao Jose dos Campos, SP (Brazil); Silva, Cassia F. [Faculdade de Tecnologia Sao Francisco - FATESF, Av. Siqueira Campos, 1174, CEP: 12207-000, Jacarei, SP (Brazil)

2013-05-06T23:59:59.000Z

396

Non-destructive method for determining neutron exposure and constituent concentrations of a body  

DOE Patents [OSTI]

A non-destructive method for determination of neutron exposure and constituent concentrations in an object, such as reactor pressure vessel, is based on the observation of characteristic gamma-rays emitted by activation products in the object by using a unique continuous gamma-ray spectrometer. The spectrometer views the object through appropriate collimators to determine the absolute emission rate of these characteristic gamma-rays, thereby ascertaining the absolute activity of given activation products in the object. These data can then be used to deduce the spatial and angular dependence of neutron exposure or the spatial constituent concentration at regions of interest within the object.

Gold, Raymond (Richland, WA); McElroy, William N. (Richland, WA)

1986-01-01T23:59:59.000Z

397

Non-destructive method for determining neutron exposure and constituent concentrations of a body  

DOE Patents [OSTI]

A non-destructive method for determination of neutron exposure and constituent concentrations in an object, such as a reactor pressure vessel, is based on the observation of characteristic gamma-rays emitted by activation products in the object by using a unique continuous gamma-ray spectrometer. The spectrometer views the object through appropriate collimators to determine the absolute emission rate of these characteristic gamma-rays, thereby ascertaining the absolute activity of given activation products in the object. These data can then be used to deduce the spatial and angular dependence of neutron exposure or the spatial constituent concentrations at regions of interest within the object.

Gold, R.; McElroy, W.N.

1984-02-22T23:59:59.000Z

398

Radiation and viral DNA  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Radiation and viral DNA Radiation and viral DNA Name: Loretta L Lamb Age: N/A Location: N/A Country: N/A Date: N/A Question: Can viral DNA be changed through exposure to radiation? If so, what type of radiation will do this? Can these irradiated viruses cause changes in the genome of any human cells they may infect? Can these (or any) viruses actually cause cancer, or do they merely act as triggering devices for cancer? Replies: In theory, any nucleic acid (viral or otherwise) can be changed by exposure to many kinds of radiation. Depending on the type of virus, these may then change the human cells that they infect. Although there are many different things that are being implicated in causing cancers, it looks like a fairly common model involves the sequential "knockout" of several human genes. Viruses may be one cause of such gene changes, radiation and other environmental causes may also contribute. Some of these changes may be inherited through families, so it becomes more likely that the environmental factors may happen to "hit" the right places in cells to cause cancers in these families. If you ask something more specific, perhaps I can focus my response a bit more

399

Radiation Sensitivity of Leukemic Progenitor Cells in Acute Nonlymphocytic Leukemia  

Science Journals Connector (OSTI)

...Foundation, Hiroshima, Japan; 2Hiroshima University...Dentistry, Hiroshima, Japan. Background: Epidemiological...A-bomb) survivors by the Radiation Effects Research Foundation...distal colorectum to radiation exposure. Citation Format...atomic bomb survivors in Japan. [abstract]. In...

Keiya Ozawa; Yasusada Miura; Toshio Suda; Kazuo Motoyoshi; and Fumimaro Takaku

1983-05-01T23:59:59.000Z

400

Radiation dose distribution for workers in South Korean nuclear power plants  

Science Journals Connector (OSTI)

......KHNP has implemented a radiation safety management system...dose registry of NPPs radiation workers, in order to...existing plants. From the software point of view, training...annual average individual radiation exposure dose is expected......

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

2010-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Enhanced Sensitivity of the RET Proto-Oncogene to Ionizing Radiation In vitro  

Science Journals Connector (OSTI)

...the RET sensitivity to ionizing radiation exposure, and to elucidate...were first exposed to ionizing radiation, electrophoresed in...Table 1 Table 1. Range of tail moment in non...for comet Radiation dose Cell line Range of tail...

Claudia Béu Volpato; Minerva Martínez-Alfaro; Raffaella Corvi; Coralie Gabus; Sylvie Sauvaigo; Pietro Ferrari; Elena Bonora; Alessandro De Grandi; and Giovanni Romeo

2008-11-01T23:59:59.000Z

402

Extremely Low Dose Ionizing Radiation Up-regulates CXC Chemokines in Normal Human Fibroblasts  

Science Journals Connector (OSTI)

...with radiation exposure (1). Ionizing radiation at moderate and higher doses (0.1-10 Gy) can produce DNA strand...death. Studies of mutants sensitive to ionizing radiation at this range of doses have revealed that the responsible genes...

Akira Fujimori; Ryuichi Okayasu; Hiroshi Ishihara; Satoshi Yoshida; Kiyomi Eguchi-Kasai; Kumie Nojima; Satoru Ebisawa; and Sentaro Takahashi

2005-11-15T23:59:59.000Z

403

Ionizing-Radiation Resistance in the Desiccation-Tolerant CyanobacteriumChroococcidiopsis  

Science Journals Connector (OSTI)

...differences between radiation-resistant and radiation-susceptible microorganisms...after exposure to high doses of X rays ranging...cultures used for radiation experiments were 3-month-old...Goleta, Calif.). Estimation of survival. To determine...

Daniela Billi; E. Imre Friedmann; Kurt G. Hofer; Maria Grilli Caiola; Roseli Ocampo-Friedmann

2000-04-01T23:59:59.000Z

404

Medical management of radiation accidents: capabilities and deployment principles of the Bundeswehr Institute of Radiobiology  

Science Journals Connector (OSTI)

......radiation-induced health impairments can be misinterpreted...of radiation-induced health impairments resulted...detection and treatment of health hazards after exposure...environment (e.g. depleted uranium), to ultraviolet radiation......

Harald Dörr; Viktor Meineke

2012-10-01T23:59:59.000Z

405

Dual Gamma Neutron Directional Elpasolite Detector  

SciTech Connect (OSTI)

Some applications, particularly in homeland security, require detection of both neutron and gamma radiation. Typically, this is accomplished with a combination of two detectors registering neutrons and gammas separately. We have investigated a new type of neutron/gamma (n/?) directional detection capability. We explored a new class of scintillator, cerium (Ce)-doped Elpasolites such as Cs2LiYCl6:Ce (CLYC), Cs2LiLaCl6 (CLLC), Cs2LiLaBr6:Ce (CLLB), or Cs2LiYBr6:Ce (CLYB). These materials are capable of providing energy resolution as good as 2.9% at 662 keV (FWHM), which is better than that of NaI:Tl. Because they contain 6Li, Elpasolites can also detect thermal neutrons. In the energy spectra, the full energy thermal neutron peak appears near or above 3 GEEn MeV. Thus, very effective pulse height discrimination is possible. In addition, the core-to-valence luminescence (CVL) provides Elpasolites with different temporal responses under gamma and neutron excitation, and, therefore, may be exploited for effective pulse shape discrimination. For instance, the CLLC emission consists of two main components: (1) CVL spanning from 220 nm to 320 nm and (2) Ce emission found in the range of 350 to 500 nm. The former emission is of particular interest because it appears only under gamma excitation. It is also very fast, decaying with a 2 ns time constant. The n/? discrimination capability of Elpasolite detectors may be optimized by tuning the cerium doping content for maximum effect on n/? pulse shape differences. The resulting Elpasolite detectors have the ability to collect neutron and gamma data simultaneously, with excellent discrimination. Further, an array of four of these Elpasolites detectors will perform directional detection in both the neutron and gamma channels simultaneously.

Guss, P. P.; Mukhopadhyay, S.

2013-09-01T23:59:59.000Z

406

Gamma ray bursts  

Science Journals Connector (OSTI)

The time histories size spectrum spatial distribution and repetition rates of gamma ray bursts are reviewed briefly. Evidence for a neutron star origin for gamma ray bursts may be found in many of these aspects of bursters. New results from optical searches are described. Substantial progress has been made recently in the optical identificaiton of the 1978 November 19 burst.

K. Hurley

1983-01-01T23:59:59.000Z

407

Optical gamma thermometer  

DOE Patents [OSTI]

An optical gamma thermometer includes a metal mass having a temperature proportional to a gamma flux within a core of a nuclear reactor, and an optical fiber cable for measuring the temperature of the heated metal mass. The temperature of the heated mass may be measured by using one or more fiber grating structures and/or by using scattering techniques, such as Raman, Brillouin, and the like. The optical gamma thermometer may be used in conjunction with a conventional reactor heat balance to calibrate the local power range monitors over their useful in-service life. The optical gamma thermometer occupies much less space within the in-core instrument tube and costs much less than the conventional gamma thermometer.

Koster, Glen Peter; Xia, Hua; Lee, Boon Kwee

2013-08-06T23:59:59.000Z

408

Gamma-ray Astronomy: Implications for Fundamental Physics  

E-Print Network [OSTI]

Gamma-ray Astronomy studies cosmic accelerators through their electromagnetic radiation in the energy range between ~100 MeV and ~100 TeV. The present most sensitive observations in this energy band are performed, from space, by the Large Area Telescope onboard the Fermi satellite and, from Earth, by the Imaging Air Cherenkov Telescopes MAGIC, H.E.S.S. and VERITAS. These instruments have revolutionized the field of Gamma-ray Astronomy, discovering different populations of gamma-ray emitters and studying in detail the non-thermal astrophysical processes producing this high-energy radiation. The scientific objectives of these observatories include also questions of fundamental physics. With gamma-ray instruments we study the origin of Galactic cosmic rays, testing the hypothesis or whether they are mainly produced in supernova explosions. Also, we obtain the most sensitive measurement of the cosmic electron-positron spectrum between 20 GeV and 5 TeV. By observing the gamma-ray emission from sources at cosmological distances, we learn about the intensity and evolution of the extragalactic background light, and perform tests of Lorentz Invariance. Moreover, we can search for dark matter by looking for gamma-ray signals produced by its annihilation or decay in over-density sites. In this paper, we review the most recent results produced with the current generation of gamma-ray instruments in these fields of research.

Javier Rico

2011-11-28T23:59:59.000Z

409

Exposure Evaluation Process  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

symptoms, further evaluation by HCP, and recommendations from evaluation by referral. It is a clinical judgment based on the history of the exposure, including what is...

410

E-Print Network 3.0 - annihilation radiation telescope Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Collection: Physics 3 MPI Kernphysik, Heidelberg Humboldt Univ. Berlin Summary: Gamma ray bursts Cosmology Diffuse extragalactic radiation fields via cutoff in AGN spectra and...

411

Low Dose Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (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,

412

Method for microbeam radiation therapy  

DOE Patents [OSTI]

A method is disclosed of performing radiation therapy on a patient, involving exposing a target, usually a tumor, to a therapeutic dose of high energy electromagnetic radiation, preferably X-ray radiation. The dose is in the form of at least two non-overlapping microbeams of radiation, each microbeam having a width of less than about 1 millimeter. Target tissue exposed to the microbeams receives a radiation dose during the exposure that exceeds the maximum dose that such tissue can survive. Non-target tissue between the microbeams receives a dose of radiation below the threshold amount of radiation that can be survived by the tissue, and thereby permits the non-target tissue to regenerate. The microbeams may be directed at the target from one direction, or from more than one direction in which case the microbeams overlap within the target tissue enhancing the lethal effect of the irradiation while sparing the surrounding healthy tissue. No Drawings

Slatkin, D.N.; Dilmanian, F.A.; Spanne, P.O.

1994-08-16T23:59:59.000Z

413

Avian inhalation exposure chamber  

DOE Patents [OSTI]

An exposure system for delivering gaseous material ranging in particle size from 0.4 micrometers to 20.0 micrometers uniformly to the heads of experimental animals, primarily birds. The system includes a vertical outer cylinder and a central chimney with animal holding bottles connected to exposure ports on the vertical outer cylinder.

Briant, James K. (P.O. Box 999, Richland, WA 99352); Driver, Crystal J. (P.O. Box 999, Richland, WA 99352)

1992-01-01T23:59:59.000Z

414

Avian inhalation exposure chamber  

DOE Patents [OSTI]

An exposure system is designed for delivering gaseous material ranging in particle size from 0.4 micrometers to 20.0 micrometers uniformly to the heads of experimental animals, primarily birds. The system includes a vertical outer cylinder and a central chimney with animal holding bottles connected to exposure ports on the vertical outer cylinder. 2 figs.

Briant, J.K.; Driver, C.J.

1992-05-05T23:59:59.000Z

415

Neutron And Gamma Detector Using An Ionization Chamber With An Integrated  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Neutron And Gamma Detector Using An Ionization Chamber Neutron And Gamma Detector Using An Ionization Chamber Neutron And Gamma Detector Using An Ionization Chamber With An Integrated Body And Moderator A detector for detecting neutrons and gamma radiation includes a cathode that defines an interior surface and an interior volume. Available for thumbnail of Feynman Center (505) 665-9090 Email Neutron And Gamma Detector Using An Ionization Chamber With An Integrated Body And Moderator A detector for detecting neutrons and gamma radiation includes a cathode that defines an interior surface and an interior volume. A conductive neutron-capturing layer is disposed on the interior surface of the cathode and a plastic housing surrounds the cathode. A plastic lid is attached to the housing and encloses the interior volume of the cathode forming an

416

Radiation: Radiation Control (Indiana)  

Broader source: Energy.gov [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,...

417

Gamma-ray Astronomy  

E-Print Network [OSTI]

The relevance of gamma-ray astronomy to the search for the origin of the galactic and, to a lesser extent, the ultra-high-energy cosmic rays has long been recognised. The current renaissance in the TeV gamma-ray field has resulted in a wealth of new data on galactic and extragalactic particle accelerators, and almost all the new results in this field were presented at the recent International Cosmic Ray Conference (ICRC). Here I summarise the 175 papers submitted on the topic of gamma-ray astronomy to the 30th ICRC in Merida, Mexico in July 2007.

Jim Hinton

2007-12-20T23:59:59.000Z

418

Neutron counting and gamma spectroscopy with PVT detectors.  

SciTech Connect (OSTI)

Radiation portals normally incorporate a dedicated neutron counter and a gamma-ray detector with at least some spectroscopic capability. This paper describes the design and presents characterization data for a detection system called PVT-NG, which uses large polyvinyl toluene (PVT) detectors to monitor both types of radiation. The detector material is surrounded by polyvinyl chloride (PVC), which emits high-energy gamma rays following neutron capture reactions. Assessments based on high-energy gamma rays are well suited for the detection of neutron sources, particularly in border security applications, because few isotopes in the normal stream of commerce have significant gamma ray yields above 3 MeV. Therefore, an increased count rate for high-energy gamma rays is a strong indicator for the presence of a neutron source. The sensitivity of the PVT-NG sensor to bare {sup 252}Cf is 1.9 counts per second per nanogram (cps/ng) and the sensitivity for {sup 252}Cf surrounded by 2.5 cm of polyethylene is 2.3 cps/ng. The PVT-NG sensor is a proof-of-principal sensor that was not fully optimized. The neutron detector sensitivity could be improved, for instance, by using additional moderator. The PVT-NG detectors and associated electronics are designed to provide improved resolution, gain stability, and performance at high-count rates relative to PVT detectors in typical radiation portals. As well as addressing the needs for neutron detection, these characteristics are also desirable for analysis of the gamma-ray spectra. Accurate isotope identification results were obtained despite the common impression that the absence of photopeaks makes data collected by PVT detectors unsuitable for spectroscopic analysis. The PVT detectors in the PVT-NG unit are used for both gamma-ray and neutron detection, so the sensitive volume exceeds the volume of the detection elements in portals that use dedicated components to detect each type of radiation.

Mitchell, Dean James; Brusseau, Charles A.

2011-06-01T23:59:59.000Z

419

State background-radiation levels: results of measurements taken during 1975-1979  

SciTech Connect (OSTI)

Background radiation levels across the United States have been measured by the Off-Site Pollutant Measurements Group of the Health and Safety Research Division at Oak Ridge National Laboratory (ORNL). These measurements have been conducted as part of the ORNL program of radiological surveillance at inactive uranium mills and sites formerly utilized during Manhattan Engineer District and early Atomic Energy Commission projects. The measurements included determination of /sup 226/Ra, /sup 232/Th, and /sup 238/U concentrations in surface soil samples and measurement of external gamma-ray exposure rates at 1 m above the ground surface at the location of soil sampling. This information is being utilized for comparative purposes to determine the extent of contamination present at the survey sites and surrounding off-site areas. The sampling program to date has provided background information at 356 locations in 33 states. External gamma-ray exposure rates were found to range from less than 1 to 34 ..mu..R/h, with an US average of 8.5 ..mu..R/h. The nationwide average concentrations of /sup 226/Ra, /sup 232/Th, and /sup 238/U in surface soil were determined to be 1.1, 0.98, and 1.0 pCi/g, respectively.

Myrick, T.E.; Berven, B.A.; Haywood, F.F.

1981-11-01T23:59:59.000Z

420

Use of gamma-ray spectroscopy for direct detection of thermal neutrons  

Science Journals Connector (OSTI)

A neutron detector based on detection of the prompt gamma-radiation emitted as a result of neutron interaction with a suitable neutron absorber is described. Boron-10 loaded polyethylene is used as the neutron...

F. Ghanbari; A. H. Mohagheghi

2001-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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

Did a gamma-ray burst initiate the late Ordovician mass extinction?  

E-Print Network [OSTI]

Gamma-ray bursts (GRBs) produce a flux of radiation detectable across the observable Universe. A GRB within our own galaxy could do considerable damage to the Earth's biosphere; rate estimates suggest that a dangerously near GRB should occur...

Melott, Adrian L.; Lieberman, Bruce S.; Laird, C. M.; Martin, Larry D.; Medvedev, Mikhail V.; Thomas, B. C.; Cannizzo, J. K.; Gehrels, N.; Jackman, C. H.

2004-01-01T23:59:59.000Z

422

Low Dose Radiation Research Program: Impact of Genetic Factors on the  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Genetic Factors on the Heritable Effects of Paternal Exposure to Genetic Factors on the Heritable Effects of Paternal Exposure to Low-Dose Radiation Janet E. Baulch University of California, Davis Why This Project? There is concern about the possible genetic effects of low dose radiation exposure. As a result, much effort has gone towards understanding mutation of cells due to radiation exposure. While recognition of the potential for mutation from exposure to ionizing radiation has led to extensive research, less effort has been given to the possible delayed risk of radiation exposure transmitted to the offspring of the exposed parent. Data from animal models show that parental exposures to DNA-damaging agents, such as ionizing radiation, predispose the offspring to serious health effects, including cancer offspring. Additionally, data from both humans and animal

423

Influence of Extraterrestrial Radiation on Radiation Portal Monitors  

SciTech Connect (OSTI)

Cosmic radiation and solar flares can be a major source of background radiation at the Earth’s surface. This paper examines the relationship between extraterrestrial radiation and the detectable background in radiation portal monitors used for homeland security applications. Background radiation data from 13 radiation portal monitor facilities are examined and compared against external sources of data related to extraterrestrial radiation, including measurements at neutron monitors located at 53 cosmic-ray observatories around the Earth, four polar orbiting satellites, three geostationary satellites, ground-based geomagnetic field data from observatories around the Earth, a solar magnetic index, solar radio flux data, and sunspot activity data. Four-years (January 2003 through December 2006) of data are used in this study, which include the latter part of Solar Cycle 23 as solar activity was on the decline. The analysis shows a significant relationship between some extraterrestrial radiation and the background detected in the radiation portal monitors. A demonstrable decline is shown in the average gamma ray and neutron background at the radiation portal monitors as solar activity declined over the period of the study.

Keller, Paul E.; Kouzes, Richard T.

2009-06-01T23:59:59.000Z

424

Gamma-Ray Bursts  

E-Print Network [OSTI]

Gamma-ray bursts are the most luminous explosions in the Universe, and their origin and mechanism are the focus of intense research and debate. More than three decades after their discovery, and after pioneering breakthroughs from space and ground experiments, their study is entering a new phase with the recently launched Swift satellite. The interplay between these observations and theoretical models of the prompt gamma ray burst and its afterglow is reviewed.

P. Meszaros

2006-05-30T23:59:59.000Z

425

Chronic Low Dose Radiation Effects on Radiation Sensitivity  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (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

426

Cross-calibration of the Transition Radiation Detector of AMS-02 for an Energy Measurement of Cosmic-Ray Ions  

E-Print Network [OSTI]

Since May 2011 the AMS-02 experiment is installed on the International Space Station and is observing cosmic radiation. It consists of several state-of-the-art sub-detectors, which redundantly measure charge and energy of traversing particles. Due to the long exposure time of AMS-02 of many years the measurement of momentum for protons and ions is limited systematically by the spatial resolution and magnetic field strength of the silicon tracker. The maximum detectable rigidity for protons is about 1.8~TV, for helium about 3.6~TV. We investigate the possibility to extend the range of the energy measurement for heavy nuclei ($Z\\geq2$) with the transition radiation detector (TRD). The response function of the TRD shows a steep increase in signal from the level of ionization at a Lorentz factor $\\gamma$ of about 500 to $\\gamma\\approx20000$, where the transition radiation signal saturates. For heavy ions the signal fluctuations in the TRD are sufficiently small to allow an energy measurement with the TRD beyond t...

Obermeier, Andreas

2014-01-01T23:59:59.000Z

427

Radiation physics, biophysics, and radiation biology  

SciTech Connect (OSTI)

Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

Hall, E.J.; Zaider, M.

1993-05-01T23:59:59.000Z

428

Sun Exposure, Vitamin D Receptor Gene Polymorphisms, and Risk of Advanced Prostate Cancer  

Science Journals Connector (OSTI)

...residence in regions of higher solar radiation (46), and the difference...exposure, including residential solar radiation, outdoor activity...Texas, Wyoming, Colorado, New Mexico, Idaho, Utah, Arizona, Nevada...states of high and/or medium solar radiation. Residence in states...

Esther M. John; Gary G. Schwartz; Jocelyn Koo; David Van Den Berg; and Sue A. Ingles

2005-06-15T23:59:59.000Z

429

VOC Exposure Metrics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

6 6 VOC Exposure Metrics ... and "Sick Building Syndrome" Figure1: The elevated odds ratios (above unity) in this figure suggest that exposures to VOCs from water-based points and solvents are associated with a variety of sick building symptions (* indicates the OR is significant at p < 0.05; ** for p < 0.01). The indoors is often regarded as safe haven from problems associated with outdoor air pollution, but a growing number of reports have suggested that exposures in indoor environments may lead to health problems. One area in which evidence has been accumulating is the relationship between working in office buildings (as opposed to industrial exposure conditions) and a variety of health effects, such as eye, nose, and throat irritation and

430

Microenvironmental Exposures to VOCs  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Microenvironmental Exposures to VOCs Microenvironmental Exposures to VOCs Speaker(s): Miranda Loh Date: February 1, 2006 - 12:00pm Location: 90-3122 The Boston Exposure Assessment in Microenvironments (BEAM) study was designed to examine the concentration distributions of VOCs in various microenvironments in and around Boston with the main objective of reducing the uncertainties in predicting exposure levels. A suite of VOC's with potential health effects including benzene, toluene, ethylbenzene, xylenes, several chlorinated compounds and aldehydes were collected in all microenvironments. Phase I. BEAM examined common non-residential microenvironments that have not been extensively studied, in particular, dining, shopping, and transportation microenvironments. Sampling using scripted activities in these microenvironments. For some compounds,

431

Oriel UV Exposure Station  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and a mask holder for standard 5" x 5" optical masks. Capabilities: Light Source 1000 Watt Hg(Xe) lamp Wavelength range: 220-450 nm Digital timer for exposure control with...

432

Exposure factors handbook  

SciTech Connect (OSTI)

The document provides a summary of the available data on various factors used in assessing human exposure including drinking-water consumption, consumption rates of broad classes of food including fruits, vegetables, beef, dairy products, and fish; soil ingestion; inhalation rate; skin area; lifetime; activity patterns; and body weight. Additionally, a number of specific exposure scenarios are identified with recommendations for default values to use when site-specific data are not available. The basic equations using these parameters to calculate exposure levels are also presented for each scenario. Default values are presented as ranges from typical to reasonable worst case and as frequency distributions where appropriate data were available. Finally, procedures for assessing the uncertainties in exposure assessments are also presented with illustrative examples. These procedures include qualitative and quantitative methods such as Monte Carlo and sensitivity analysis.

Konz, J.J.; Lisi, K.; Friebele, E.; Dixon, D.A.

1989-07-01T23:59:59.000Z

433

First observations of Y(1S)->gamma pi(+)pi(-) and Y(1S)->gamma pi(0)pi(0)  

E-Print Network [OSTI]

We report on a study of exclusive radiative decays of the Y(1S) resonance collected with the CLEO II detector operating at the Cornell Electron Storage Ring. We present the first observation of the radiative decays Y(1S) --> gamma pi(+)pi(-) and Y(1...

Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Darling, C.; Davis, Robin E. P.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan; Zhou, L.

1999-01-01T23:59:59.000Z

434

Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation Globus Ruth NASA Ames Research Center Abstract Osteoporosis profoundly affects the aging U.S. population and exposure to high doses of radiation causes bone loss similar to age-related osteoporosis, although the influence of low dose radiation exposures is not known. The central hypothesis of our DOE project (NASA supplement) is that low doses of radiation modulate subsequent skeletal degeneration via oxidative pathways. Our working hypothesis is that a prior exposure to low dose radiation regulates oxidative metabolism within bone and contributes to bone loss caused either by subsequent high, challenge doses of radiation or by aging. HZE source: Because astronauts are exposed to radiation from GCR and solar

435

TL detectors for gamma ray dose measurements in criticality accidents  

Science Journals Connector (OSTI)

......both the neutron and the gamma...radiation field induced by criticality...with both neutron and photon...the neutron spectrum can improve...on neutron energy i.e...251017 fissions, t=35s...data about energy spectrum, the choice...shielding from thermal neutrons (containing......

Saveta Miljanic; Benjamin Zorko; Beatriz Gregori; Zeljka Knezevic

2007-07-01T23:59:59.000Z

436

Large-Scale Anisotropy of EGRET Gamma Ray Sources  

E-Print Network [OSTI]

In the course of its operation, the EGRET experiment detected high-energy gamma ray sources at energies above 100 MeV over the whole sky. In this communication, we search for large-scale anisotropy patterns among the catalogued EGRET sources using an expansion in spherical harmonics, accounting for EGRET's highly non-uniform exposure. We find significant excess in the quadrupole and octopole moments. This is consistent with the hypothesis that, in addition to the galactic plane, a second mid-latitude (5^{\\circ} < |b| < 30^{\\circ}) population, perhaps associated with the Gould belt, contributes to the gamma ray flux above 100 MeV.

Luis Anchordoqui; Thomas McCauley; Thomas Paul; Olaf Reimer; Diego F. Torres

2005-06-24T23:59:59.000Z

437

Factorization in B ---> V gamma decays  

SciTech Connect (OSTI)

The factorization properties of the radiative decays B {yields} V{gamma} are analyzed at leading order in 1/m{sub b} using the soft-collinear effective theory. It is shown that the decay amplitudes can be expressed in terms of a B {yields} V form factor evaluated at q{sup 2} = 0, light-cone distribution amplitudes of the B and V mesons, and calculable hard-scattering kernels. The renormalization-group equations in the effective theory are solved to resum perturbative logarithms of the different scales in the decay process. Phenomenological implications for the B {yields} K*{gamma} branching ratio, isospin asymmetry, and CP asymmetries are discussed, with particular emphasis on possible effects from physics beyond the Standard Model.

Becher, Thomas; /Fermilab; Hill, Richard J.; /SLAC; Neubert, Matthias; /Cornell U., LEPP

2005-03-01T23:59:59.000Z

438

Neutron-driven gamma-ray laser  

DOE Patents [OSTI]

A lasing cylinder emits laser radiation at a gamma-ray wavelength of 0.87 .ANG. when subjected to an intense neutron flux of about 400 eV neutrons. A 250 .ANG. thick layer of Be is provided between two layers of 100 .ANG. thick layer of .sup.57 Co and these layers are supported on a foil substrate. The coated foil is coiled to form the lasing cylinder. Under the neutron flux .sup.57 Co becomes .sup.58 Co by neutron absorption. The .sup.58 Co then decays to .sup.57 Fe by 1.6 MeV proton emission. .sup.57 Fe then transitions by mesne decay to a population inversion for lasing action at 14.4 keV. Recoil from the proton emission separates the .sup.57 Fe from the .sup.57 Co and into the Be, where Mossbauer emission occurs at a gamma-ray wavelength.

Bowman, Charles D. (Los Alamos, NM)

1990-01-01T23:59:59.000Z

439

Factorization in B to V gamma Decays  

SciTech Connect (OSTI)

The factorization properties of the radiative decays B {yields} V{gamma} are analyzed at leading order in 1/mb using the soft-collinear effective theory. It is shown that the decay amplitudes can be expressed in terms of a B {yields} V form factor evaluated at q{sup 2} = 0, light-cone distribution amplitudes of the B and V mesons, and calculable hard-scattering kernels. The renormalization-group equations in the effective theory are solved to resume perturbative logarithms of the different scales in the decay process. Phenomenological implications for the B {yields} K*{gamma} branching ratio, isospin asymmetry, and CP asymmetries are discussed, with particular emphasis on possible effects from physics beyond the Standard Model.

Becher, T

2005-03-28T23:59:59.000Z

440

Nano {gamma}'/{gamma}'' composite precipitates in Alloy 718  

SciTech Connect (OSTI)

Nanoscale composite precipitates of Alloy 718 have been investigated with both high-resolution scanning transmission electron microscopy and phase field modeling. Chemical analysis via energy-dispersive x-ray spectroscopy allowed for the differentiation of {gamma}' and {gamma}'' particles, which is not otherwise possible through traditional Z-contrast methods. Phase field modeling was applied to determine the stress distribution and elastic interaction around and between the particles, respectively, and it was determined that a composite particle (of both {gamma}' and {gamma}'') has an elastic energy that is significantly lower than, for example, single {gamma}' and {gamma}'' precipitates which are non-interacting.

Phillips, P. J. [Department of Physics, University of Illinois at Chicago, Chicago, Illinois 60607 (United States); McAllister, D.; Gao, Y.; Lv, D.; Williams, R. E. A.; Wang, Y.; Mills, M. J. [Department of Materials Science and Engineering, Ohio State University, Columbus, Ohio 43210 (United States); Peterson, B. [Honeywell Aerospace, Phoenix, Arizona 85034 (United States)

2012-05-21T23:59:59.000Z

Note: This page contains sample records for the topic "gamma radiation exposure" 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.


441

Optomechanical design of a prompt gamma reaction history diagnostic  

SciTech Connect (OSTI)

The National Ignition Facility and the Omega Laser Facility both have a need for measuring prompt gamma radiation as part of a nuclear diagnostic program. A new gamma-detection diagnostic using off-axis-parabolic mirrors has been built. Some new techniques were used in the design, construction, and tolerancing of this gamma ray diagnostic. Because of the wavelength requirement (250 to 700 nm), the optical element surface finishes were a key design consideration. The optical enclosure had to satisfy pressure safety concerns and shielding against electromagnetic interference induced by gammas and neutrons. Structural finite element analysis was needed to meet rigorous optical and safety requirements. The optomechanical design is presented. Alignment issues are also discussed.

Kaufman, Morris I; Frogget, Brent C; Tunnel, Thomas W; Cox, Brian; Frayer, Daniel K; Ali, Zaheer; Herrmann, Hans

2009-09-10T23:59:59.000Z

442

Optomechanical design of a prompt gamma reaction history diagnostic  

SciTech Connect (OSTI)

The National Ignition Facility and the Omega Laser Facility both have a need for measuring prompt gamma radiation as part of a nuclear diagnostic program. A new gamma-detection diagnostic using off-axis-parabolic mirrors has been built. Some new techniques were used in the design, construction, and tolerancing of this gamma ray diagnostic. Because of the wavelength requirement (250-700 nm), the optical element surface finishes were a key design consideration. The optical enclosure had to satisfy pressure safety concerns and shielding against electromagnetic interference induced by gammas and neutrons. Structural finite element analysis was needed to meet rigorous optical and safety requirements. The optomechanical design is presented. Alignment issues are also discussed.

Hermann, Hans W [Los Alamos National Laboratory; Kaufman, Morris I [Los Alamos National Laboratory; Malone, Robert M [NSTEC; Frogget, Brent C [NSTEC; Tunnell, Thomas W [NSTEC; Cox, Brian [NSTEC; Frayer, Daniel K [NSTEC; Ali, Zaheer [NSTEC; Stoeffl, Wolfgang [LLNL

2009-01-01T23:59:59.000Z

443

Neutron and gamma irradiation damage to organic materials.  

SciTech Connect (OSTI)

This document discusses open literature reports which investigate the damage effects of neutron and gamma irradiation on polymers and/or epoxies - damage refers to reduced physical chemical, and electrical properties. Based on the literature, correlations are made for an SNL developed epoxy (Epon 828-1031/DDS) with an expected total fast-neutron fluence of {approx}10{sup 12} n/cm{sup 2} and a {gamma} dosage of {approx}500 Gy received over {approx}30 years at < 200 C. In short, there are no gamma and neutron irradiation concerns for Epon 828-1031/DDS. To enhance the fidelity of our hypotheses, in regards to radiation damage, we propose future work consisting of simultaneous thermal/irradiation (neutron and gamma) experiments that will help elucidate any damage concerns at these specified environmental conditions.

White, Gregory Von, II; Bernstein, Robert

2012-04-01T23:59:59.000Z

444

Vitamin E: tocopherols and tocotrienols as potential radiation countermeasures  

Science Journals Connector (OSTI)

......TUNEL (terminal deoxynucleotidyl transferase mediated dUTP nick end labeling)- and PUMA- (p53 upregulated modulator of apoptosis...gamma-radiation injury. The above results suggest that TS may merit further development using appropriate large animal models for......

Vijay K. Singh; Lindsay A. Beattie; Thomas M. Seed

2013-11-01T23:59:59.000Z

445

Natural radiation environment III. [Lead Abstract  

SciTech Connect (OSTI)

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

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

1980-01-01T23:59:59.000Z

446

Apparatuses and methods for detecting, identifying and quantitating radioactive nuclei and methods of distinguishing neutron stimulation of a radiation particle detector from gamma-ray stimulation of a detector  

DOE Patents [OSTI]

In one aspect, the invention encompasses a method of detecting radioactive decay, comprising: a) providing a sample comprising a radioactive material, the radioactive material generating decay particles; b)providing a plurality of detectors proximate the sample, the detectors comprising a first set and a second set, the first set of the detectors comprising liquid state detectors utilizing liquid scintillation material coupled with photo tubes to generate a first electrical signal in response to decay particles stimulating the liquid scintillation material, the second set of the detectors comprising solid state detectors utilizing a crystalline solid to generate a second electrical signal in response to decay particles stimulating the crystalline solid; c) stimulating at least one of the detectors to generate at least one of the first and second electrical signals, the at least one of the first and second electrical signals being indicative of radioactive decay in the sample. In another aspect, the invention encompasses an apparatus for identifying and quantitating radioactive nuclei of a sample comprising radioactive material that decays to generate neutrons and high-energy .gamma.-rays.

Cole, Jerald D. (Idaho Falls, ID); Drigert, Mark W. (Idaho Falls, ID); Reber, Edward L. (Idaho Falls, ID); Aryaeinejad, Rahmat (Idaho Falls, ID)

2001-01-01T23:59:59.000Z

447

Low Dose Radiation Research Program: About  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

About About Background. Extensive research on the health effects of radiation using standard epidemiological and toxicological approaches has been done for decades to characterize responses of populations and individuals to high radiation doses, and to set exposure standards to protect both the public and the workforce. These standards were set using models that extrapolated from the cancers observed following exposure to high doses of radiation to predicted, but not measurable, changes in cancer frequency at low radiation doses. The use of models was necessary because of our inability to detect changes in cancer incidence following low doses of radiation. Historically, the predominant approach has been the Linear-no-Threshold model (see Wikipedia entry) and collective dose concept that assumes each unit of radiation, no

448

RADIATION SAFETY OFFICE Campus Radiation Safety Manual UNIVERSITY OF NEW ORLEANS Previous Revision: May 1999  

E-Print Network [OSTI]

measures: a. Personnel will be made aware of management's commitment to maintain low exposure levels. b. Management will periodically review operating procedures with the Radiation Safety Officer to determine steps taken to reduce exposures. c. Management will ensure that the person, or persons, selected

Li, X. Rong

449

Guidelines for Exposure Assessment  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Z-92/001 Z-92/001 May 1992 Guidelines for Exposure Assessment Published on May 29, 1992, Federal Register 57(104):22888-22938 These guidelines replace the previously issued final Guidelines for Estimating Exposures (September 24, 1986), Federal Register 51(185):34042-34054, and the Proposed Guidelines for Exposure-Related Measurements (December 2, 1988), Federal Register 53(232):48830- 48853. Risk Assessment Forum U.S. Environmental Protection Agency Washington, DC DISCLAIMER This document has been reviewed in accordance with U.S. Environmental Protection Agency policy and approved for publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. Note: This document represents the final guidelines. A number of editorial corrections have

450

Molecular stress response in the CNS of mice after systemic exposureto interferon-alpha, ionizing radiation and ketamine  

SciTech Connect (OSTI)

We previously showed that the expression of troponin T1 (Tnnt 1) was induced in the central nervous system (CNS) of adultmice 30 min after treatment with ketamine, a glutamate N-methyl-D-aspartic acid (NMDA) receptor antagonist. We hypothesized that Tnnt 1 expression may be an early molecular biomarker of stress response in the CNS of mice. To further evaluate this hypothesis, we investigated the regional expression of Tnnt 1 in the mouse brain using RNA in situ hybridization 4 h after systemic exposure to interferon-a (IFN-a) and gamma ionizing radiation, both of which have be associated with wide ranges of neuropsychiatric complications. Adult B6C3F1 male mice were treated with either human IFN-a (a single i.p. injection at 1 x 105 IU/kg) or whole body gamma-radiation (10 cGy or 2 Gy). Patterns of Tnnt 1 transcript expression were compared in various CNS regions after IFN-a, radiation and ketamine treatments (previous study). Tnnt 1 expression was consistently induced in pyramidal neurons of cerebral cortex and hippocampus after all treatment regimens including 10 cGy of ionizing radiation. Regional expression of Tnnt 1 was induced in Purkinje cells of cerebellum after ionizing radiation and ketamine treatment; but not after IFN-a treatment. None of the three treatments induced Tnnt 1 expression in glial cells. The patterns of Tnnt 1 expression in pyramidal neurons of cerebral cortex andhippocampus, which are both known to play important roles in cognitive function, memory and emotion, suggest that the expression of Tnnt 1 may be an early molecular biomarker of induced CNS stress.

Lowe, Xiu R.; Marchetti, Francesco; Lu, Xiaochen; Wyrobek, Andrew J.

2009-03-03T23:59:59.000Z

451

A Systems Genetic Approach to Identify Low Dose Radiation-Induced Lymphoma Susceptibility/DOE2013FinalReport  

SciTech Connect (OSTI)

The ultimate goal of this project is to identify the combinations of genetic variants that confer an individual's susceptibility to the effects of low dose (0.1 Gy) gamma-radiation, in particular with regard to tumor development. In contrast to the known effects of high dose radiation in cancer induction, the responses to low dose radiation (defined as 0.1 Gy or less) are much less well understood, and have been proposed to involve a protective anti-tumor effect in some in vivo scientific models. These conflicting results confound attempts to develop predictive models of the risk of exposure to low dose radiation, particularly when combined with the strong effects of inherited genetic variants on both radiation effects and cancer susceptibility. We have used a Â?Â?Systems Genetics approach in mice that combines genetic background analysis with responses to low and high dose radiation, in order to develop insights that will allow us to reconcile these disparate observations. Using this comprehensive approach we have analyzed normal tissue gene expression (in this case the skin and thymus), together with the changes that take place in this gene expression architecture a) in response to low or high- dose radiation and b) during tumor development. Additionally, we have demonstrated that using our expression analysis approach in our genetically heterogeneous/defined radiation-induced tumor mouse models can uniquely identify genes and pathways relevant to human T-ALL, and uncover interactions between common genetic variants of genes which may lead to tumor susceptibility.

Balmain, Allan [University of California, San Francisco; Song, Ihn Young [University of California, San Francisco

2013-05-15T23:59:59.000Z

452

Hybrid model of GeV-TeV gamma ray emission from Galactic Center  

E-Print Network [OSTI]

The observations of high energy $\\gamma$-ray emission from the Galactic center (GC) by HESS, and recently by Fermi, suggest the cosmic ray acceleration in the GC and possibly around the supermassive black hole. In this work we propose a lepton-hadron hybrid model to explain simultaneously the GeV-TeV $\\gamma$-ray emission. Both electrons and hadronic cosmic rays were accelerated during the past activity of the GC. Then these particles would diffuse outwards and interact with the interstellar gas and background radiation field. The collisions between hadronic cosmic rays with gas is responsible to the TeV $\\gamma$-ray emission detected by HESS. With fast cooling in the strong radiation field, the electrons would cool down and radiate GeV photons through inverse Compton scattering off the soft background photons. This scenario provides a natural explanation of the observed GeV-TeV spectral shape of $\\gamma$-rays.

Yi-Qing Guo; Qiang Yuan; Cheng Liu; Ai-Feng Li

2014-09-14T23:59:59.000Z

453

Historical Exposures to Chemicals at the Rocky Flats Nuclear Weapons Plant: A Pilot Retrospective Exposure Assessment  

SciTech Connect (OSTI)

In a mortality study of white males who had worked at the Rocky Flats Nuclear Weapons Plant between 1952 and 1979, an increased number of deaths from benign and unspecified intracranial neoplasms was found. A case-control study nested within this cohort investigated the hypothesis that an association existed between brain tumor death and exposure to either internally deposited plutonium or external ionizing radiation. There was no statistically significant association found between estimated radiation exposure from internally deposited plutonium and the development of brain tumors. Exposure by job or work area showed no significant difference between the cohort and the control groups. An update of the study found elevated risk estimates for (1) all lymphopoietic neoplasms, and (2) all causes of death in employees with body burdens greater than or equal to two nanocuries of plutonium. There was an excess of brain tumors for the entire cohort. Similar cohort studies conducted on worker populations from other plutonium handling facilities have not yet shown any elevated risks for brain tumors. Historically, the Rocky Flats Nuclear Weapons Plant used large quantities of chemicals in their production operations. The use of solvents, particularly carbon tetrachloride, was unique to Rocky Flats. No investigation of the possible confounding effects of chemical exposures was done in the initial studies. The objectives of the present study are to (1) investigate the history of chemical use at the Rocky Flats facility; (2) locate and analyze chemical monitoring information in order to assess employee exposure to the chemicals that were used in the highest volume; and (3) determine the feasibility of establishing a chemical exposure assessment model that could be used in future epidemiology studies.

Janeen Denise Robertson

1999-02-01T23:59:59.000Z

454

7 - Estimation of Radiation Doses  

Science Journals Connector (OSTI)

Abstract Radiation doses to the Japanese population from inhalation of contaminated air, external irradiation, terrestrial and marine food contamination are estimated and compared with other sources of anthropogenic (global fallout, Chernobyl accident), natural (radionuclides in food, cosmic radiation) and medical applications (X-ray tests, CT-tests, etc.) of ionizing radiation. The estimated doses from inhalation, ingestion of terrestrial and marine food, and radiation exposure from radioactive clouds and deposited radionuclides were generally below the levels which could cause health damage of the Japanese population, as well as of the world population. The estimated total radiation doses to fish and shellfish in coastal waters during the largest radionuclide releases were by a factor of 10 lower than the baseline safe level postulated for the marine organisms, therefore no harmful effects are expected for the marine ecosystem as well.

Pavel P. Povinec; Katsumi Hirose; Michio Aoyama

2013-01-01T23:59:59.000Z

455

About Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Radiation 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 naturally occurring radioactive materials such as uranium, thorium, radon, and certain forms of potassium and carbon. The air we breathe contains radon, the food we eat contains uranium and thorium from the soil, and our bodies contain radioactive forms of potassium and carbon. Cosmic radiation from the sun also contributes to our natural radiation dose. We also receive radiation doses from man-made sources such as X-rays, nuclear medical procedures, power plants, smoke detectors and older television sets. Some people, such as nuclear plant operators, flight crews, and nuclear medicine staff may also receive an occupational radiation dose.

456

Gamma Ray Bursts  

E-Print Network [OSTI]

Gamma-ray bursts have been detected at photon energies up to tens of GeV. We review some recent developments in the X-ray to GeV photon phenomenology in the light of Swift and Fermi observations, and some of the theoretical models developed to explain them, with a view towards implications for C.T.A.

Peter Mészáros

2012-04-12T23:59:59.000Z

457

Natural gamma radioactivity in the villages of Kanyakumari District, Tamil Nadu, India  

Science Journals Connector (OSTI)

......Terrestrial gamma radiation dose rate is also an important...contribution to the average dose rate received by the...population(6,7). The estimation of radiation dose distribution is important...side (Gulf of Mannar/Bay of Bengal coast). The district......

Jeni Chandar Padua; M. R. Basil Rose

2013-08-01T23:59:59.000Z

458

Gamma-ray burst models  

Science Journals Connector (OSTI)

...research-article Discussion Meeting Issue Gamma-ray bursts organized by Alan Wells, Ralph...J. Wijers and Martin Rees Gamma-ray burst models Andrew King * * ( ark...various possibilities for making gamma-ray bursts, particularly from close binaries...

2007-01-01T23:59:59.000Z

459

Low Dose Radiation Research Program: Linking Molecular Events to Cellular  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Linking Molecular Events to Cellular Responses at Low Dose Exposures Linking Molecular Events to Cellular Responses at Low Dose Exposures Thomas Weber Pacific Northwest National Laboratory Why This Project It currently costs billions of dollars to protect workers and the public from exposure to man-made radiation, despite exposure levels lower than the natural background levels of radiation. If it could be demonstrated that there is no increased cancer risk associated with these low dose exposures, these resources could be directed toward more critical societal issues. Defining low dose radiation cancer risks is limited by our ability to measure and directly correlate relevant cellular and molecular responses occurring at the low radiation dose and dose rate with tumor formation. This deficiency has led to conservative risk assessments based on low dose

460

Low Dose Radiation Research Program: Genetic Factors Affecting  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Affecting Susceptibility to Low-Dose Radiation Affecting Susceptibility to Low-Dose Radiation William F. Morgan Pacific Northwest National Laboratory Why This Project The short-term effects of high doses of ionizing radiation on cellular responses are relatively well understood. Less clear are the long-term consequences of exposure to low dose/low dose-rate radiation and the effects of radiation exposure on the progeny of surviving cells. If a cell survives radiation, it is generally thought to have repaired all the radiation-induced insults and be capable of a "normal healthy life". At a certain frequency, however, we have found that some cells surviving radiation grow normally, but will rearrange their genetic material during time in culture. We call this radiation-induced genomic instability. Many

Note: This page contains sample records for the topic "gamma radiation exposure" 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.


461

Low Dose Radiation Research Program: DOE / NASA Joint Funded Projects  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

DOE/NASA Joint Funded Projects DOE/NASA Joint Funded Projects NASA Source Photo Space explorers are subject to exposure to low dose ionizing radiation. Research that helps determine health risks from this exposure is funded by NASA and DOE. Source: NASA DOE's Low Dose Program and the National Aeronautics and Space Administration (NASA) jointly fund new research to develop a better scientific basis for understanding risks to humans from exposures to low doses or low fluences of ionizing radiation. Research must focus on elucidating molecular mechanisms and pathways involved in normal radiobiological responses to low dose exposure, and must have the potential to ultimately increase understanding of health outcomes from radiation exposures that are at or near current workplace exposure

462

Radioactivity level in soil of a palaeo beach in the south-eastern part of Bangladesh and evaluation of radiation hazard  

Science Journals Connector (OSTI)

......outdoor and indoor radiation hazard indices...annual effective dose rates. MATERIALS...Denundation of the Bay of Bengal extending along...kg). Gamma radiation hazard indices...based on the estimation that 1 Bq kg...gamma radiation dose rates. The index......

Ashna Islam; Mahfuza Sharifa Sultana; Aleya Begum; Selina Yeasmin

2013-12-01T23:59:59.000Z

463

Simulated Irradiation of Samples in HFIR for use as Possible Test Materials in the MPEX (Material Plasma Exposure Experiment) Facility  

SciTech Connect (OSTI)

The importance of Plasma Material Interaction (PMI) is a major concern in fusion reactor design and analysis. The Material-Plasma Exposure eXperiment (MPEX) facility will explore PMI under fusion reactor plasma conditions. Samples with accumulated displacements per atom (DPA) damage produced by irradiations in the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) will be studied in the MPEX facility. The project presented in this paper involved performing assessments of the induced radioactivity and resulting radiation fields of a variety of potential fusion reactor materials. The scientific code packages MCNP and SCALE were used to simulate irradiation of the samples in HFIR; generation and depletion of nuclides in the material and the subsequent composition, activity levels, gamma radiation fields, and resultant dose rates as a function of cooling time. These state-of-the-art simulation methods were used in addressing the challenge of the MPEX project to minimize the radioactive inventory in the preparation of the samples for inclusion in the MPEX facility.

Ellis, Ronald James [ORNL; Rapp, Juergen [ORNL

2014-01-01T23:59:59.000Z

464

E-Print Network 3.0 - acute x-ray exposure Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

late effects of acute ionizing radiation exposures in atomic bomb survivors" initiated October 2009... X-ray Yes Yes No No Retesting required 2 X-ray Yes Yes No No Retesting...

465

The Galactic gamma-ray club  

E-Print Network [OSTI]

The exclusive Galactic gamma-ray club has opened up to new members. Supernova remnants, pulsar wind nebulae, and massive binary systems hosting a compact object have recently joined the young pulsars as firmly established sources of gamma rays in the Milky Way. Massive young stellar clusters are on the waiting list to join the club. Only the fine imaging recently obtained at TeV energies could resolve specific sources. The samples are sparse, but raise exciting questions. The jet or pulsar-wind origin of the emission in binaries has been hotly debated, but it seems that both types of systems have been recently detected. The nature of the radiation in shock accelerators is still questioned: do nuclei contribute a lot, a little, or not to the gamma rays and what energy do they carry away from the shock budget? The acceleration process and the structural evolution of the pulsar winds are still uncertain. The magnetic field distribution in all these systems is a key, but poorly constrained, ingredient to model the multi-wavelength data, particle transport and electron ageing. It must, however, be determined in order to efficiently probe particle distributions and the acceleration mechanisms. The source samples soon to be expected from GLAST and the Cherenkov telescopes should bring new valuable test cases and they will, for the first time, shed statistical light on the collective behaviour of these different types of accelerators.

Isabelle A. Grenier

2008-04-02T23:59:59.000Z

466

Solution To The Gamma Ray Burst Mystery?  

E-Print Network [OSTI]

Photoexcitation and ionization of partially ionized heavy atoms in highly relativistic flows by interstellar photons, followed by their reemission in radiative recombination and decay, boost star-light into beamed $\\gamma$ rays along the flow direction. Repeated excitation/decay of highly relativistic baryonic ejecta from merger or accretion induced collapse of neutron stars in dense stellar regions (DSRs), like galactic cores, globular clusters and super star-clusters, can convert enough kinetic energy in such events in distant galaxies into cosmological gamma ray bursts (GRBs). The model predicts remarkably well all the main observed temporal and spectral properties of GRBs. Its success strongly suggests that GRBs are $\\gamma$ ray tomography pictures of DSRs in galaxies at cosmological distances with unprecedented resolution: A time resolution of $dt\\sim 1~ms$ in a GRB can resolve stars at a Hubble distance which are separated by only $D\\sim 10^{10}cm$. This is equivalent to the resolving power of an optical telescope with a diameter larger than one Astronomical Unit!

Nir J. Shaviv; Arnon Dar

1996-08-21T23:59:59.000Z

467

Causal Analysis of the Unanticipated Extremity Exposure at HFEF  

SciTech Connect (OSTI)

This report covers the unintended extremity exposure to an operator while handling a metallurgical mount sample of irradiated fuel following an off-scale high beta radiation reading of the sample. The decision was made to continue working after the meter indicated high off-scale by the HPT Supervisor, which resulted in the operator at the next operation being exposed.

David E. James; Charles R. Posegate; Thomas P. Zahn; Alan G. Wagner

2011-11-01T23:59:59.000Z

468

Danger radiations  

ScienceCinema (OSTI)

Le conférencier Mons.Hofert parle des dangers et risques des radiations, le contrôle des zones et les précautions ŕ prendre ( p.ex. film badge), comment mesurer les radiations etc.

None

2011-04-25T23:59:59.000Z

469

Application of the gamma evaluation method in Gamma Knife film dosimetry  

SciTech Connect (OSTI)

Purpose: Gamma Knife (GK) radiosurgery is a minimally invasive surgical technique for the treatment of intracranial lesions. To minimize neurological deficits, submillimeter accuracy is required during treatment delivery. In this paper, the delivery accuracy of GK radiosurgery was assessed with the gamma evaluation method using planning dose distribution and film measurement data. Methods: Single 4, 8, and 16 mm and composite shot plans were developed for evaluation using the GK Perfexion (PFX) treatment planning system (TPS). The planning dose distributions were exported as digital image communications in medicine - radiation therapy (DICOM RT) files using a new function of GK TPS. A maximum dose of 8 Gy was prescribed for four test plans. Irradiation was performed onto a spherical solid water phantom using Gafchromic EBT2 films in the axial and coronal planes. The exposed films were converted to absolute dose based on a 4th-order polynomial calibration curve determined using ten calibration films. The film measurement results and planning dose distributions were registered for further analysis in the same Leksell coordinate using in-house software. The gamma evaluation method was applied to two dose distributions with varying spatial tolerance (0.3-2.0 mm) and dosimetric tolerance (0.3-2.0%), to verify the accuracy of GK radiosurgery. The result of gamma evaluation was assessed using pass rate, dose gamma index histogram (DGH), and dose pass rate histogram (DPH). Results: The 20, 50, and 80% isodose lines found in film measurements were in close agreement with the planning isodose lines, for all dose levels. The comparison of diagonal line profiles across the axial plane yielded similar results. The gamma evaluation method resulted in high pass rates of >95% within the 50% isodose line for 0.5 mm/0.5% tolerance criteria, in both the axial and coronal planes. They satisfied 1.0 mm/1.0% criteria within the 20% isodose line. Our DGH and DPH also showed that low isodose lines exhibited inferior gamma indexes and pass rates compared with higher isodose lines. Conclusions: The gamma evaluation method was applicable to GK radiosurgery. For all test plans, planning dose distribution and film measurement met the tolerance criteria of 0.5 mm/0.5% within the 50% isodose line which are used for marginal dose prescription.

Park, Jeong-Hoon; Han, Jung Ho; Kim, Chae-Yong; Oh, Chang Wan; Lee, Do-Heui; Suh, Tae-Suk; Gyu Kim, Dong; Chung, Hyun-Tai [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam 463-707, Korea and Department of Biomedical Engineering, College of Medicine, Catholic University of Korea Seoul 137-701 (Korea, Republic of); Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam 463-707, Korea and Department of Neurosurgery, College of Medicine, Seoul National University, Seoul 110-799 (Korea, Republic of); Department of Neurosurgery, Asan Medical Center, College of Medicine, University of Ulsan, Seoul 138-736 (Korea, Republic of); Department of Biomedical Engineering and Research Institute of Biomedical Engineering, College of Medicine, Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Department of Neurosurgery, College of Medicine, Seoul National University, Seoul 110-799 (Korea, Republic of)

2011-10-15T23:59:59.000Z