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1

Low dose ionizing radiation (IR) signaling regulation in vivo...  

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

studies from our lab indicated that human cells exposed to low doses of IR caused growth stimulation, speeding cells up in their cell cycle division (i.e., checkpoint regulation),...

2

Ionizing Radiation  

Science Conference Proceedings (OSTI)

*. Bookmark and Share. Ionizing Radiation Measurements. Fees for services are located directly below the technical contacts ...

2013-04-09T23:59:59.000Z

3

Ionizing Radiation Dosimetry  

Science Conference Proceedings (OSTI)

Ionizing Radiation Dosimetry. ... OH. US Air Force Radiation Dosimetry Laboratory, Wright-Patterson - Base, OH [100548- 0] PA. ...

2013-09-06T23:59:59.000Z

4

Protection Against Ionizing Radiation in Extreme Radiation ...  

Science Conference Proceedings (OSTI)

Protection Against Ionizing Radiation in Extreme Radiation-resistant Microorganisms. ... Elucidated radiation protection by intracellular halides. ...

2013-05-01T23:59:59.000Z

5

NVLAP Ionizing Radiation Dosimetry LAP  

Science Conference Proceedings (OSTI)

Ionizing Radiation Dosimetry LAP. ... This site has been established for applicants to the accreditation program for ionizing radiation dosimetry. ...

2013-07-23T23:59:59.000Z

6

NIST Ionizing Radiation Division - 2001  

Science Conference Proceedings (OSTI)

... The Ionizing Radiation Division of the Physics Laboratory supports the ... meaningful, and compatible measurements of ionizing radiations (x rays ...

7

NIST Ionizing Radiation Division - 1998  

Science Conference Proceedings (OSTI)

TECHNICAL ACTIVITIES 1998 - NISTIR 6268 IONIZING RADIATION DIVISION. The Neutron Interferometer. The neutron ...

8

NIST Ionizing Radiation Division - 2000  

Science Conference Proceedings (OSTI)

"Technical Activities 2000" - Table of Contents, Division home page. Ionizing Radiation Division. ...

9

Ionizing radiation detector  

DOE Patents (OSTI)

An ionizing radiation detector is provided which is based on the principal of analog electronic integration of radiation sensor currents in the sub-pico to nano ampere range between fixed voltage switching thresholds with automatic voltage reversal each time the appropriate threshold is reached. The thresholds are provided by a first NAND gate Schmitt trigger which is coupled with a second NAND gate Schmitt trigger operating in an alternate switching state from the first gate to turn either a visible or audible indicating device on and off in response to the gate switching rate which is indicative of the level of radiation being sensed. The detector can be configured as a small, personal radiation dosimeter which is simple to operate and responsive over a dynamic range of at least 0.01 to 1000 R/hr.

Thacker, L.H.

1989-06-08T23:59:59.000Z

10

Ionizing radiation detector  

DOE Patents (OSTI)

An ionizing radiation detector is provided which is based on the principle of analog electronic integration of radiation sensor currents in the sub-pico to nano ampere range between fixed voltage switching thresholds with automatic voltage reversal each time the appropriate threshold is reached. The thresholds are provided by a first NAND gate Schmitt trigger which is coupled with a second NAND gate Schmitt trigger operating in an alternate switching state from the first gate to turn either a visible or audible indicating device on and off in response to the gate switching rate which is indicative of the level of radiation being sensed. The detector can be configured as a small, personal radiation dosimeter which is simple to operate and responsive over a dynamic range of at least 0.01 to 1000 R/hr.

Thacker, Louis H. (Knoxville, TN)

1990-01-01T23:59:59.000Z

11

Ionizing Radiation Division Quality Manual  

Science Conference Proceedings (OSTI)

... 08 47020C Low-energy Photon Brachytherapy Seeds, ... Calibrated for Surface Dose Rate 10 ... Sources Calibrated for Radiation Protection Ionization ...

2012-03-08T23:59:59.000Z

12

Using Co-Regulation to Understand Low-Dose Ionizing Radiation...  

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

with low and high doses of ionizing radiation (IR). Pathway analysis suggested that chromatin structure, as well as transcription control, plays a large role in linking gene...

13

Functional Proteomic Pattern Identification under Low Dose Ionizing Radiation  

Science Conference Proceedings (OSTI)

The goal of this study is to explore and to understand the dynamic responses of signaling pathways to low dose ionizing radiation (IR). Low dose radiation (10 cGy or lower) affects several signaling pathways including DNA repair, survival, cell cycle, ... Keywords: low dose radiation, functional proteomics

Young Bun Kim; Jean Gao; Ying Dong; Chin-Rang Yang

2008-11-01T23:59:59.000Z

14

Ionizing Radiation Injury (South Carolina)  

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

This legislation applies to employers that have more than one employee who engages in activities which involve the presence of ionizing radiation. Employers with less than three employees can...

15

Lesson 4 - Ionizing Radiation | Department of Energy  

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

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

16

NIST Ionizing Radiation Division 2000 - Future Directions  

Science Conference Proceedings (OSTI)

... will enable dose-reconstruction studies for populations exposed at the natural background levels of ionizing radiation. Calibrations of Low-Energy ...

17

Low dose ionizing radiation induces tumor growth promoting factors in  

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

ionizing radiation induces tumor growth promoting factors in ionizing radiation induces tumor growth promoting factors in stress-induced premature senescent fibroblasts David Boothman University of Texas Southwestern Medical Center at Dallas Abstract Recent evidence suggest that the causes of cancer development are not limited to mutations within cancer cells, but also involve in alterations of cancer microenvironment. Senescent cells are irreversibly growth arrested, but remain metabolically active. Senescent cells, especially senescent fibroblasts in the stroma may provide a beneficial environment for tumor growth through secretion of certain factors. Accumulation of senescent cells in the stroma of patients repeatedly exposed to low doses of IR or low dose rates of IR, could be an important factor, causing alteration of the microenvironment that ultimately benefits tumor

18

Low Dose Radiation Research Program: Comparisons of IR and ROS for  

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

Comparisons of IR and ROS for Induction of Damage to Cells Comparisons of IR and ROS for Induction of Damage to Cells Kathryn D. Held1, Yvonne L. McCarey1, Laurence Tartier1, Elena V. Rusyn1, Giuseppe Schettino2, Melvyn Folkard2, Kevin M. Prise2, and Barry D. Michael2 1Department of Radiation Oncology, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02114; 2Gray Laboratory Cancer Research Trust, Mount Vernon Hospital, Northwood, HA6 2JR, UK Accurate evaluation of the risks associated with exposure to low doses of ionizing radiation (IR) is a major challenge for environmental sciences. Studies on the mechanisms of the actions of low doses of IR are needed to help understand possible risks. IR exerts its effects on cells through production of reactive oxidizing species (ROS) such as ·OH, H2O2 and

19

Testing a Model of IR Radiative Losses: Preprint  

DOE Green Energy (OSTI)

Thermopile pyranometers exhibit IR radiative losses that affect global and diffuse shortwave measurements made with first class thermopile based instruments. Pyrgeometers can be used to measure the sky temperature and are used to calculate the pyranometer?s IR radiative losses.

Vignola, F.; Long, C. N.; Reda, I.

2009-08-01T23:59:59.000Z

20

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

E-Print Network (OSTI)

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

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

Ionization of Rydberg atoms by blackbody radiation  

E-Print Network (OSTI)

We have studied an ionization of alkali-metal Rydberg atoms by blackbody radiation (BBR). The results of the theoretical calculations of ionization rates of Li, Na, K, Rb and Cs Rydberg atoms are presented. Calculations have been performed for nS, nP and nD states which are commonly used in a variety of experiments, at principal quantum numbers n=8-65 and at the three ambient temperatures of 77, 300 and 600 K. A peculiarity of our calculations is that we take into account the contributions of BBR-induced redistribution of population between Rydberg states prior to photoionization and field ionization by extraction electric field pulses. The obtained results show that these phenomena affect both the magnitude of measured ionization rates and shapes of their dependences on n. A Cooper minimum for BBR-induced transitions between bound Rydberg states of Li has been found. The calculated ionization rates are compared with our earlier measurements of BBR-induced ionization rates of Na nS and nD Rydberg states with ...

Beterov, I I; Ryabtsev, I I; Entin, V M; Ekers, A; Bezuglov, N N

2008-01-01T23:59:59.000Z

22

Composite scintillators for detection of ionizing radiation  

DOE Patents (OSTI)

Applicant's present invention is a composite scintillator having enhanced transparency for detecting ionizing radiation comprising a material having optical transparency wherein said material comprises nano-sized objects having a size in at least one dimension that is less than the wavelength of light emitted by the composite scintillator wherein the composite scintillator is designed to have selected properties suitable for a particular application.

Dai, Sheng (Knoxville, TN); Stephan, Andrew Curtis (Knoxville, TN); Brown, Suree S. (Knoxville, TN); Wallace, Steven A. (Knoxville, TN); Rondinone, Adam J. (Knoxville, TN)

2010-12-28T23:59:59.000Z

23

Alloy nanoparticle synthesis using ionizing radiation  

DOE Patents (OSTI)

A method of forming stable nanoparticles comprising substantially uniform alloys of metals. A high dose of ionizing radiation is used to generate high concentrations of solvated electrons and optionally radical reducing species that rapidly reduce a mixture of metal ion source species to form alloy nanoparticles. The method can make uniform alloy nanoparticles from normally immiscible metals by overcoming the thermodynamic limitations that would preferentially produce core-shell nanoparticles.

Nenoff, Tina M. (Sandia Park, NM); Powers, Dana A. (Albuquerque, NM); Zhang, Zhenyuan (Durham, NC)

2011-08-16T23:59:59.000Z

24

Waveshifters and Scintillators for Ionizing Radiation Detection  

Science Conference Proceedings (OSTI)

Scintillation and waveshifter materials have been developed for the detection of ionizing radiation in an STTR program between Ludlum Measurements, Inc. and the University of Notre Dame. Several new waveshifter materials have been developed which are comparable in efficiency and faster in fluorescence decay than the standard material Y11 (K27) used in particle physics for several decades. Additionally, new scintillation materials useful for fiber tracking have been developed which have been compared to 3HF. Lastly, work was done on developing liquid scintillators and paint-on scintillators and waveshifters for high radiation environments.

B.Baumgaugh; J.Bishop; D.Karmgard; J.Marchant; M.McKenna; R.Ruchti; M.Vigneault; L.Hernandez; C.Hurlbut

2007-12-11T23:59:59.000Z

25

Dosimetry for non-ionizing radiation  

SciTech Connect

Several commercially available phosphor-teflon dosimeters were subjected to thermal fade studies. The thermoluminescence dosimetry (TLD) tags were washed and air dried prior to each ionizing radiation pretreatment. Readings made over 3 weeks on the CaF2:Mn and CaF2:Dy TLD tags did not produce measurable thermal-fade characteristics for the 22 to 31/sup 0/C temperature range. Nonionizing radiation treatments were at 2.45 GHz. While the results obtained did demonstrate decreases in signal levels over time and temperature changes, the patterns were not smooth, making it impossible to establish differences in TLD readings as quantitative measures of temperature differences which could serve as measures of long-term exposures to nonionizing radiation. The authors concluded that, due to the irregularities that existed in the thermal fade characteristics, the dosimeter would not be suitable for quantifying exposures to nonionizing radiation. There was significant potential in the device, however, as an indicator of radiation leakage or exposure.

Fanslow, G.E.

1981-03-01T23:59:59.000Z

26

NIST Ionizing Radiat. Div. - 2004: Strategic Focus 1  

Science Conference Proceedings (OSTI)

... and to determine exposure or dose-rate values ... to maximize the energy absorption of the ionizing radiation. ... the calibration of an 55 Fe low-energy x ...

27

22.01 Introduction to Ionizing Radiation, Fall 2003  

E-Print Network (OSTI)

Introduction to basic properties of ionizing radiations and their uses in medicine, industry, science, and environmental studies. Discusses natural and man-made radiation sources, energy deposition and dose calculations, ...

Coderre, Jeffrey A.

28

Effects of prenatal exposure to ionizing radiation  

SciTech Connect

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

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

1990-07-01T23:59:59.000Z

29

Ionizing radiation downregulates ASPM, a gene responsible for microcephaly in humans  

SciTech Connect

Microcephaly is a malformation associated with in utero exposed atomic bomb survivors and can be induced in mice by fetal exposure to ionizing radiation (IR). The pathogenesis of IR-induced microcephaly, however, has not been fully understood. Our analyses of high-coverage expression profiling (HiCEP) demonstrated that the abnormal spindle-like microcephaly associated gene (ASPM) was down-regulated in irradiated human diploid fibroblasts. ASPM was recently reported as the causative gene for MCPH-5, the most common type of congenital microcephaly in humans. Here, we show that the expression of the Aspm gene was significantly reduced by IR in various human and murine cells. Additionally, Aspm was found downregulated in the irradiated fetal mouse brain, particularly in the ventricular zones. A similar suppression was observed in the irradiated neurosphere cultures. This is the first report suggesting that the suppression of Aspm by IR could be the initial molecular target leading to the future microcephaly formation.

Fujimori, Akira [Cellular and Molecular Biology Team, National Institute of Radiological Sciences, Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan)], E-mail: fujimora@nirs.go.jp; Yaoi, Takeshi; Ogi, Hiroshi [Department of Pathology and Applied Neurobiology, Kyoto Prefectural University of Medicine, Graduate School of Medical Sciences, Kawaramachi Hirokoji, Kamigyo-ku, Kyoto 602-8566 (Japan); Wang Bing [National Institute of Radiological Sciences, Heavy-Ion Radiology Research Group, Research Center for Charged Particle Therapy, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Suetomi, Katsutoshi; Sekine, Emiko; Yu Dong; Kato, Takamitsu [Cellular and Molecular Biology Team, National Institute of Radiological Sciences, Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Takahashi, Sentaro [National Institute of Radiological Sciences, Heavy-Ion Radiology Research Group, Research Center for Charged Particle Therapy, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Okayasu, Ryuichi [Cellular and Molecular Biology Team, National Institute of Radiological Sciences, Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Itoh, Kyoko; Fushiki, Shinji [Department of Pathology and Applied Neurobiology, Kyoto Prefectural University of Medicine, Graduate School of Medical Sciences, Kawaramachi Hirokoji, Kamigyo-ku, Kyoto 602-8566 (Japan)

2008-05-09T23:59:59.000Z

30

Ionizing Radiation Activates AMP-Activated Kinase (AMPK): A Target for Radiosensitization of Human Cancer Cells  

SciTech Connect

Purpose: Adenosine monophosphate (AMP)-activated kinase (AMPK) is a molecular energy sensor regulated by the tumor suppressor LKB1. Starvation and growth factors activate AMPK through the DNA damage sensor ataxia-telangiectasia mutated (ATM). We explored the regulation of AMPK by ionizing radiation (IR) and its role as a target for radiosensitization of human cancer cells. Methods and Materials: Lung, prostate, and breast cancer cells were treated with IR (2-8 Gy) after incubation with either ATM or AMPK inhibitors or the AMPK activator metformin. Then, cells were subjected to either lysis and immunoblotting, immunofluorescence microscopy, clonogenic survival assays, or cell cycle analysis. Results: IR induced a robust phosphorylation and activation of AMPK in all tumor cells, independent of LKB1. IR activated AMPK first in the nucleus, and this extended later into cytoplasm. The ATM inhibitor KU-55933 blocked IR activation of AMPK. AMPK inhibition with Compound C or anti-AMPK {alpha} subunit small interfering RNA (siRNA) blocked IR induction of the cell cycle regulators p53 and p21{sup waf/cip} as well as the IR-induced G2/M arrest. Compound C caused resistance to IR, increasing the surviving fraction after 2 Gy, but the anti-diabetic drug metformin enhanced IR activation of AMPK and lowered the surviving fraction after 2 Gy further. Conclusions: We provide evidence that IR activates AMPK in human cancer cells in an LKB1-independent manner, leading to induction of p21{sup waf/cip} and regulation of the cell cycle and survival. AMPK appears to (1) participate in an ATM-AMPK-p21{sup waf/cip} pathway, (2) be involved in regulation of the IR-induced G2/M checkpoint, and (3) may be targeted by metformin to enhance IR responses.

Sanli, Toran; Rashid, Ayesha; Liu Caiqiong [Department of Oncology, Juravinski Cancer Center and McMaster University, Hamilton, Ontario (Canada)

2010-09-01T23:59:59.000Z

31

Rules and Regulations for Control of Ionizing Radiation (Arkansas) |  

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

Rules and Regulations for Control of Ionizing Radiation (Arkansas) Rules and Regulations for Control of Ionizing Radiation (Arkansas) Rules and Regulations for Control of Ionizing Radiation (Arkansas) < Back Eligibility Utility Program Info State Arkansas Program Type Environmental Regulations Siting and Permitting Provider Department of Health The Rules and Regulations for Control of Ionizing Radiation are the Arkansas state laws made in accordance the federal Nuclear Regulatory Commission Rules. Any contractor with the US DOE or US Nuclear Regulatory Commission is exempt from the state laws. This set of rules and regulations basically restates the federal policy to ensure that Arkansas is in compliance with the federal standards governing nuclear energy. Specifically the State rules are equivalent to Nuclear Regulatory

32

Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation  

NLE Websites -- All DOE Office Websites (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

33

Composite scintillators for detection of ionizing radiation ...  

Building Energy Efficiency; Electricity Transmission; Energy Analysis; Energy ... Fluorescent Nanoparticles for Radiation DetectionFluorescent Nanoparticles for ...

34

NIST Ionizing Radiation Division 1999 - Current Directions  

Science Conference Proceedings (OSTI)

... effect relationships for radiation-induced stochastic ... validate the EPR dose assessment methods ... Calibration of Low-Energy Photon Brachytherapy ...

35

The ionizing radiation environment in space and its effects  

Science Conference Proceedings (OSTI)

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

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

2012-11-20T23:59:59.000Z

36

Implied Dynamic Feedback of 3D IR Radiative Transfer on Simulated...  

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

of 3D IR Radiative Transfer on Simulated Cloud Fields D. B. Mechem and Y. L. Kogan Cooperative Institute for Mesoscale Meteorological Studies University of Oklahoma Norman,...

37

NIST Ionizing Radiation Division 1999 - Future Directions  

Science Conference Proceedings (OSTI)

... to test the applicability of EPR tooth enamel retrospective dosimetry to dose assessment of background radiation. The low-dose threshold (dose ...

38

NIST Ionizing Radiation Division 2001 - Program Directions  

Science Conference Proceedings (OSTI)

... seen a tremendous increase in the use of low-energy photon ... for the high levels of absorbed dose used in the industrial radiation processing of ...

39

NIST Ionizing Radiation Division 1998 - Current Directions  

Science Conference Proceedings (OSTI)

... Cs gamma-ray ranges, and the low-energy photon ... beam, and a high-dose- rate Gammacell used in our radiation-processing dosimetry ...

40

Concerns with low-level ionizing radiation  

SciTech Connect

Populations have been studied in geographic areas of increased natural radiation, in radiation-exposed workers, in patients medically exposed, and in accidental exposures. No reproducible evidence exists of harmful effects from increases in background radiation three to ten times the usual levels. There is no increase in leukemia or other cancers among American military participants in nuclear testing, no increase in leukemia or thyroid cancer among medical patients receiving {sup 131}I for diagnosis or treatment of hypothyroidism, and no increase in lung cancer among nonsmokers exposed to increased radon in the home. The association of radiation with the atomic bomb and with excessive regulatory and health physics as-low-as-reasonably-achievable (ALARA) radiation levels practices has created a climate of fear about the dangers of radiation at any level. However, there is no evidence that radiation exposures at the levels equivalent to medical usage are harmful. The unjustified excessive concern with radiation at any level, however, precludes beneficial uses of radiation and radioactivity in medicine, science, and industry.

Yalow, R.S.

1994-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

Metabolomic Response of Human Skin Tissue to Low Dose Ionizing Radiation  

Science Conference Proceedings (OSTI)

Understanding how human organs respond to ionizing radiation (IR) at a systems biology level and identifying biomarkers for IR exposure at low doses can help provide a scientific basis for establishing radiation protection standards. Little is known regarding the physiological responses to low dose IR at the metabolite level, which represents the end-point of biochemical processes inside cells. Using a full thickness human skin tissue model and GC-MS-based metabolomics analysis, we examined the metabolic perturbations at three time points (3, 24 and 48 hr) after exposure to 3, 10 and 200 cGy of X-rays. PLS-DA score plots revealed dose- and time-dependent clustering between sham and irradiated groups. Importantly, a comparable number of metabolites were detected to have significant change 48 hr after exposure to 3 and 10 cGy of irradiation, when compared with the high dose of 200 cGy. Biochemical pathway analysis showed perturbations to DNA/RNA damage and repair, lipid and energy metabolisms, even at low doses of IR.

Hu, Zeping; Kim, Young-Mo; Sowa, Marianne B.; Robinson, Robert J.; Gao, Xiaoli; Metz, Thomas O.; Morgan, William F.; Zhang, Qibin

2012-05-18T23:59:59.000Z

42

Ionic Liquids and Ionizing Radiation: Reactivity of Highly Energetic  

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

Ionizing Radiation: Reactivity of Highly Energetic Ionizing Radiation: Reactivity of Highly Energetic Species James F. Wishart J. Phys. Chem. Lett. 1, 3225-3231 (2010). [Find paper at ACS Publications] or use ACS Articles on Request View the video on this Perspective article at The Journal of Physical Chemistry Letters (5:03) Selected for the ACS Special Virtual Issue on Ionic Liquids (March 2011). Abstract: Due to their unique properties, ionic liquids present many opportunities for basic research on the interactions of radiation with materials under conditions not previously available. At the same time, there are practical applied reasons for characterizing, understanding, and being able to predict how ionic-liquid-based devices and industrial-scale systems will perform under conditions of extreme reactivity, including radiation. This

43

Low Dose Radiation Research Program: Research Highlights - Ionizing  

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

Affects Cancer Frequency and Characteristics by Acting Affects Cancer Frequency and Characteristics by Acting on the Microenvironment Background: For more than a quarter century the scientific rationale for extrapolating radiation health effects has been underpinned by biophysical target theory. Fundamental to target theory is that the effect (e.g., DNA damage, mutation, cancer) is proportional to dose based on interaction of energy with biological targets, specifically DNA. However, the biology following ionizing radiation is more than just DNA damage, repair, or misrepair. Cellular responses to ionizing radiation can affect phenotype, cell interactions, lineage commitment, differentiation and genomic stability, all of which have been widely documented in cultured cells and many observed in vivo. This class of non-targeted effects induced

44

To: John R. Novak Radiation Safety - IRS From: G. T. Lonergan Radiation Safety - II§  

Office of Legacy Management (LM)

7, 19% 7, 19% To: John R. Novak Radiation Safety - IRS From: G. T. Lonergan Radiation Safety - II§ Subject: Extrusion of Billets, Titus Metals, Inc., Waterloo, Iowa A grpup of ANL aqloyees consisting of LE. Walker and S. Matsas (MET), E. Leverens (SSE), I(. C.~Buffy'(SPM), and G. T. Lonergan (IRS), traveled to Waterloo, Iowa, on June 29 where they accomplished the extrusion of U308 billets into fuel plates for Argonaut. Prior to beginning the extrusion operation, the floor area around the press, run-out table, stretch straightener, and all accessible portions of the press were surveyed. No activity was detected. The floor area from the furnace (uhere the billets were heated) to the press was coveredwith a layer of vinyl approximately 48fl wide and topped

45

Computational phenotype prediction of ionizing-radiation-resistant bacteria with a multiple-instance learning model  

Science Conference Proceedings (OSTI)

Ionizing-radiation-resistant bacteria (IRRB) are important in biotechnology. The use of these bacteria for the treatment of radioactive wastes is determined by their surprising capacity of adaptation to radionuclides and a variety of toxic molecules. ... Keywords: ionizing-radiation-resistant bacteria, ionizing-radiation-sensitive bacteria, multiple-instance learning, phenotypic prediction, protein sequences

Sabeur Aridhi; Mondher Maddouri; Haitham Sghaier; Engelbert Mephu Nguifo

2013-08-01T23:59:59.000Z

46

Low Dose Radiation Research Program: Low Dose Ionizing Radiation-Induced  

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

Low Dose Ionizing Radiation-Induced Effects in Irradiated and Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated cells: Pathways Analysis in Support of Risk Assessment. Authors: B.E. Lehnert, R. Cary, D. Gadbois, and G. Gupta. Institutions: Bioscience Division, Los Alamos National Laboratory. The scientific literature presents a confusing picture concerning health risks due to low dose ionizing radiation (LDIR), e.g., <1-10 cGy. Some effects of LDIR such as enhanced rates of cell proliferation and the induction of radioadaptation may be benign under some circumstances. Other evidence suggests LDIR can be hazardous and that a threshold for potentially detrimental responses, e.g., increases in intracellular reactive oxygen species (ROS), increases in sister chromatid exchanges (SCE), alterations in gene or protein expression profiles, and increased

47

Development of Pattern Recognition Software for Tracks of Ionizing Radiation In Medipix2-Based  

E-Print Network (OSTI)

, and area monitors to characterize the general background radiation environment harmful to humansDevelopment of Pattern Recognition Software for Tracks of Ionizing Radiation In Medipix2-Based tool for the automated identification and classification of tracks of ionizing radiation as measured

Vilalta, Ricardo

48

Low Dose Ionizing Radiation Modulates Immune Function New Project Overview  

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

Modulates Immune Function New Project Overview Modulates Immune Function New Project Overview Gregory Nelson Loma Linda University Abstract The immune system provides the first line of defense for exposures to environmental hazards. Protective immunity mechanisms using innate or adaptive responses are employed to mitigate acute challenges or amplify the readiness of the system to respond to future challenges. Some stimuli lead to amplified inflammatory reactions such as delayed hypersensitivity which is required for immunity to parasites and can also lead to adverse consequences such as contact dermatitis. Radiation exposure has the potential to aggravate hypersensitivity reactions as well as to suppress protective immunity. Ionizing radiation at high doses has long been recognized as highly effective in destroying cells of the immune system,

49

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

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

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

50

Role of ATM kinase in ionizing radiation induced DNA damage response...  

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

ATM kinase in ionizing radiation induced DNA damage response in human neural stemprogenitor cells and differentiated cell types Adayabalam Balajee Columbia University Medical...

51

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

E-Print Network (OSTI)

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

Davidson, Matthew Allen

2011-01-01T23:59:59.000Z

52

Ionizing radiation risks to satellite power systems (SPS) workers  

DOE Green Energy (OSTI)

The radiation risks to the health of workers who will construct and maintain solar power satellites in the space environment were examined. For ionizing radiation, the major concern will be late or delayed health effects, particularly the increased risk of radiation-induced cancer. The estimated lifetime risk for cancer is 0.8 to 5.0 excess deaths per 10,000 workers per rad of exposure. Thus, for example, in 10,000 workers who completed ten missions with an exposure of 40 rem per mission, 320 to 2000 additional deaths in excess of the 1640 deaths from normally occurring cancer, would be expected. These estimates would indicate a 20 to 120% increase in cancer deaths in the worker-population. The wide range in these estimates stems from the choice of the risk-projection model and the dose-response relationsip. The choice between a linear and a linear-quadratic dose-response model may alter the risk estimate by a factor of about two. The method of analysis (e.g., relative vs absolute risk model) can alter the risk estimate by an additional factor of three. Choosing different age and sex distributions can further change the estimate by another factor of up to three. The potential genetic consequences could be of significance, but at the present time, sufficient information on the age and sex distribution of the worker population is lacking for precise estimation of risk. The potential teratogenic consequences resulting from radiation are considered significant. Radiation exposure of a pregnant worker could result in developmental abnormalities.

Lyman, J.T.; Ainsworth, E.J.; Alpen, E.L.; Bond, V.; Curtis, S.B.; Fry, R.J.M.; Jackson, K.L.; Nachtwey, S.; Sondhaus, C.; Tobias, C.A.; Fabrikant, J.I.

1980-11-01T23:59:59.000Z

53

Recombining WMAP: constraints on ionizing and resonance radiation at recombination  

E-Print Network (OSTI)

We place new constraints on sources of ionizing and resonance radiation at the epoch of the recombination process using the recent CMB temperature and polarization spectra coming from WMAP. We find that non-standard recombination scenarios are still consistent with the current data. In light of this we study the impact that such models can have on the determination of several cosmological parameters. In particular, the constraints on curvature and baryon density appear to be weakly affected by a modified recombination scheme. However, it may affect the current WMAP constraints on inflationary parameters like the spectral index and its running. Physically motivated models, like those based on primordial black hole or super heavy dark matter decay, are able to provide a good fit to the current data. Future observations in both temperature and polarization will be needed to more stringently test these models.

Rachel Bean; Alessandro Melchiorri; Joe Silk

2003-06-18T23:59:59.000Z

54

CORROSION PRODUCT TRANSPORT AND DEPOSITION UNDER IONIZING RADIATION  

DOE Green Energy (OSTI)

A study was made of corrosion product transport and deposition on Zircaloy-2 and AISI 304 stainless steel in the presence and absence of ionizing radiation. Three 100-hour irradiation tests, using 2-Mev electrons from a Van de Graaff accelerator, and four 100-hour nonradiation tests were performed in 6O0 deg F pressurized water. Data from the seven runs and an additional exploratory run are presented. In addition, complete experimental procedures and descriptions of the apparatus are included. Control of pH was obtained by using H and OH form ion exchange resias for pH 7 and Li and OH form ion exchange resins for pH 10. The major conclusion to be drawn from the present work is that the deposition on Zircaloy-2 at pH 10 and 600 deg F is higher than on AISI 304 stainless steel at the same conditions. (auth)

Thomas, C.C. Jr.; Lacock, H.W.; Cadoff, H.Y. ed.

1958-12-01T23:59:59.000Z

55

IONIZING RADIATION RISKS TO SATELLITE POWER SYSTEMS (SPS) WORKERS  

E-Print Network (OSTI)

and A. I. Sladkova, "Radiation Levels in InterplanetaryPrognoz Satellites," Cosmic Radiation, 12_, No. 5, 716-718 (0. ArchamDeau, Mammalian Radiation Lethargy, A Disturbance

Lyman, J.T.

2010-01-01T23:59:59.000Z

56

Regulation of Annexin A2 by Ionizing Radiation in Human Skin...  

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

Annexin A2 by Ionizing Radiation in Human Skin Equivalent Culture: Does A Nuclear Annexin A2-Protein Kinase C Epsilon Complex Contribute To Reduced Cancer Risks At Low Dose...

57

Regulation of Annexin A2 by Ionizing Radiation in Human Skin...  

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

of Annexin A2 by Ionizing Radiation in Human Skin Equivalent Culture: Does A Nuclear Annexin A2-Protein Kinase C Epsilon Complex Contribute To Reduced Cancer Risks At Low...

58

Terrace-like structure in the above-threshold ionization spectrum of an atom in an IR+XUV two-color laser field  

E-Print Network (OSTI)

Based on the frequency-domain theory, we investigate the above-threshold ionization (ATI) process of an atom in a two-color laser field with infrared (IR) and extreme ultraviolet (XUV) frequencies, where the photon energy of the XUV laser is close to or larger than the atomic ionization threshold. By using the channel analysis, we find that the two laser fields play different roles in an ionization process, where the XUV laser determines the ionization probability by the photon number that the atom absorbs from it, while the IR laser accelerates the ionized electron and hence widens the electron kinetic energy spectrum. As a result, the ATI spectrum presents a terrace-like structure. By using the saddle-point approximation, we obtain a classical formula which can predict the cutoff of each plateau in the terrace-like ATI spectrum. Furthermore, we find that the difference of the heights between two neighboring plateaus in the terrace-like structure of the ATI spectrum increases as the frequency of the XUV lase...

Zhang, Kui; Fu, Panming; Yan, Zong-Chao; Wang, Bingbing

2013-01-01T23:59:59.000Z

59

Mechanisms Underlying Cellular Responses to Low Doses/Low LET Ionizing Radiation in Primary Haemopoietic Cells.  

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

Mechanisms Underlying Cellular Responses to Low Doses/Low LET Ionizing Radiation Mechanisms Underlying Cellular Responses to Low Doses/Low LET Ionizing Radiation in Primary Haemopoietic Cells. Munira Kadhim 1 , Stefania Militi 1 , Debbie Bowler 1 , Denise Macdonald 1 and Kevin Prise 2 1 Radiation and Genome Stability Unit, MRC, Harwell, Didcot, Oxon, OX11 0RD, UK 2 Gray Cancer Institute ,PO Box 100, Mount Vernon Hospital, Northwood, HA6 2JR, UK Because the human population is genetically heterogeneous, it is important to understand the role that heterogeneity may play in radiation response. Exposure to ionizing radiation can lead to a suite of changes, including increased mutation rate, delayed reproductive cell death, and delayed chromosomal aberrations, all of which are manifestations of the complex genomic instability (GI) phenotype. Following exposure to either high LET

60

Radiation-induced attenuation of high-OH optical fibers after hydrogen treatment in the presence of ionizing radiation  

DOE Green Energy (OSTI)

High purity, high-OH, optical fibers were irradiated in a hydrogen atmosphere to explore hydrogen binding into defects created by the ionizing radiation. Significant improvements in subsequent measurements of radiation-induced attenuation were observed. 18 refs., 4 figs., 2 tabs.

Lyons, P.B; Looney, L.D.

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

Use of ionizing radiation for fixing textile resins on wool. [Gamma rays  

SciTech Connect

Ambient-temperature treatments with ionizing radiation can be used as an alternative to conventional thermal/catalytic cure methods of fixing textile resins on wool materials. The effectiveness of the radiation-induced fixation of resins on wool has been demonstrated by machine-wash shrinkage tests on fabrics treated with a variety of commercial polymer resins.

McLaren, K.G.

1980-04-01T23:59:59.000Z

62

Identification of novel ionizing radiation signaling targets in reconstituted human skin  

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

of novel ionizing radiation signaling targets in reconstituted human skin of novel ionizing radiation signaling targets in reconstituted human skin Feng Yang, Katrina M. Waters, Bobbie-Jo Webb-Robertson, Lye-Meng Markillie, Rachel M. Wirgau, Shawna M. Hengel, Ljiljana Pasa-Tolic, and David L. Stenoien. Pacific Northwest National Laboratory Our focus has been on identifying the early events that occur after low dose ionizing radiation exposure that precede and often regulate downstream events such as altered transcription, protein secretion and epigenetic regulation. Phosphorylation is one of the earliest detectible events that occurs following radiation exposure and plays important roles in multiple biological pathways including DNA damage repair, transcription, apoptosis, and cell cycle progression. Very robust

63

Development of sup 1 sup 9 sup 2 Ir radiation sources for intravascular irradiation  

E-Print Network (OSTI)

Intravascular brachytherapy is a novel therapy for preventing the restenosis of coronary artery by use of low-dose irradiation. JAERI and Kyoto University have been developing sup 1 sup 9 sup 2 Ir radiation sources by the cooperative research project entitled as 'The research on safety and effectiveness of the intravascular brachytherapy for preventing restenosis of the coronary artery disease' since 1998. The radiation source was introduced into the stenosis through a catheter (a guide-tube to insert directly into vascular) to irradiate the diseased part. Ten sup 1 sup 9 sup 2 Ir seed sources (phi 0.4 mm x 2.5 mm) were positioned between nylon spacers (phi 0.3 mm x 1.0 mm) in a flexible covering tube and the tube was plugged with a core-wire; the tube was shrunk to fix the inside materials and the size is 0.46 mm in diameter and 3 m in length. The physically optimal design was determined to insert the radiation source easily into vascular and to get the dose uniformity in the diseased part. The production me...

Kogure, H; Iwamoto, S; Iwata, K; Kawauchi, Y; Nagata, Y; Sorita, T; Suzuki, K

2003-01-01T23:59:59.000Z

64

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

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

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

65

Low-Dose Ionizing Radiation Alters the Epigenome of the Avy Mouse  

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

Ionizing Radiation Alters the Epigenome of the A Ionizing Radiation Alters the Epigenome of the A vy Mouse Autumn Bernal 1,2,3 , Dale Huang 1 , Yue Li 4 , Dana Dolinoy 5 , and Randy Jirtle 1 Department of Radiation Oncology 1 , University Program in Genetics and Genomic 2 , Integrated Toxicology & Environmental Health Program 3 , Department of Community and Family Medicine 4 , Duke University Medical Center, Durham, NC, USA, Department of Environmental and Health Sciences, University of Michigan, Ann Arbor, MI, USA 4 Background: Humans have evolved and thrived amidst constant low-dose (0-10 cGy) background radiation exposure from natural sources. Currently, however, the frequency of exposures to low doses of radiation is increasing due to man-made sources such as diagnostic imaging and nuclear power. This increased exposure has led to concerns amongst the general public and the government about the

66

Low Dose Radiation Research Program: Research Highlights - Ionizing...  

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

of Energy Low Dose Radiation Research Program, and the Department of Defense Breast Cancer Research program and Prostate Cancer Research program. Researchers include Eva...

67

NIST Ionizing Radiat. Div. - 2004: Strategic Focus 3  

Science Conference Proceedings (OSTI)

... of high levels of absorbed dose, as required in the industrial radiation processing of ... tremendous increase in the use of low-energy, photon ...

68

NIST Ionizing Radiat. Div. - 2002: Strategic Focus 3  

Science Conference Proceedings (OSTI)

... of high levels of absorbed dose, as required in the industrial radiation processing of ... tremendous increase in the use of low-energy, photon ...

69

NIST Ionizing Radiat. Div. - 2004: Strategic Focus 2  

Science Conference Proceedings (OSTI)

... electronic radiation monitors ("pagers"), isotope identifier instruments ... 2003, DOE recognized this program as one of the top-ten programs relevant to ...

70

Does nitrate deposition following astrophysical ionizing radiation events pose an additional threat to amphibians?  

E-Print Network (OSTI)

It is known that amphibians are especially susceptible to the combination of heightened UVB radiation and increased nitrate concentrations. Various astrophysical events have been suggested as sources of ionizing radiation that could pose a threat to life on Earth, through destruction of the ozone layer and subsequent increase in UVB, followed by deposition of nitrate. In this study, we investigate whether the nitrate deposition following an ionizing event is sufficiently large to cause an additional stress beyond that of the heightened UVB previously considered. We have converted predicted nitrate depositions to concentration values, utilizing data from the New York State Department of Environmental Conservation Acid Rain Monitoring Network web site. Our results show that the increase in nitrate concentration in bodies of water following the most intense ionization event likely in the last billion years would not be sufficient to cause a serious additional stress on amphibian populations and may actually provide some benefit by acting as fertilizer.

Brian C. Thomas; Michelle D. Honeyman

2008-04-22T23:59:59.000Z

71

Amphibian nitrate stress as an additional terrestrial threat from astrophysical ionizing radiation events?  

E-Print Network (OSTI)

As diversity in amphibian species declines, the search for causes has intensified. Work in this area has shown that amphibians are especially susceptible to the combination of heightened UVB radiation and increased nitrate concentrations. Various astrophysical events have been suggested as sources of ionizing radiation that could pose a threat to life on Earth, through destruction of the ozone layer and subsequent increase in UVB, followed by deposition of nitrate. In this study, we investigate whether the nitrate deposition following an ionizing event is sufficiently large to cause an additional stress beyond that of the heightened UVB previously considered. We have converted predicted nitrate depositions to concentration values, utilizing data from the New York State Department of Environmental Conservation Acid Rain Monitoring Network web site. Our results show that the increase in nitrate concentration in bodies of water following the most intense ionization event likely in the last billion years would no...

Thomas, Brian C

2008-01-01T23:59:59.000Z

72

Detection of Ionizing Radiation by Plasma-Panel Sensors: Cosmic Muons, Ion Beams, and Cancer Therapy  

Science Conference Proceedings (OSTI)

The plasma panel sensor is an ionizing photon and particle radiation detector derived from PDP technology with high gain and nanosecond response. Experimental results in detecting cosmic ray muons and beta particles from radioactive sources are described along with applications including high energy and nuclear physics, homeland security and cancer therapeutics.

Friedman, Dr. Peter S. [Integrated Sensors, LLC; Ferretti, Claudio [University of Michigan; Ball, Robert [University of Michigan; Beene, James R [ORNL; Ben Moshe, M. [Tel Aviv University; Benhammou, Yan [Tel Aviv University; Chapman, J. Wehrley [University of Michigan; Levin, Daniel S. [University of Michigan; Silver, Yiftah [Tel Aviv University; Weaverdyck, Curtis [University of Michigan; Zhou, Bing [University of Michigan; Etzion, E [Tel Aviv University; Moshe, M. [Tel Aviv University; Bentefour, E [Ion Beam Applications

2012-01-01T23:59:59.000Z

73

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

SciTech Connect

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

74

The effects of diet and ionizing radiation on azoxymethane induced colon carcinogenesis  

E-Print Network (OSTI)

The ability of ionizing radiation to enhance colon carcinogenesis and the role of diet in this process has not been documented. We hypothesized that radiation would enhance the formation of aberrant crypt foci, ACF, known precursor lesions to colon cancer, by suppressing apoptosis and upregulating proliferation in colonocytes. Diets contained a combination of fish oil or corn oil and either pectin or cellulose. We exposed 40 male Sprague-Dawley rats to 1 Gy ionizing radiation (1 GeV Fe) 10 d prior to injection with AOM. Colons were resected at the promotion stage of carcinogenesis (7 wk post initial injection) and assayed for ACF and apoptosis. Radiation treatment increased (P=0.0327) the incidence of high multiplicity ACF (foci with four or more aberrant crypts) and decreased (P=0.0340) the apoptotic index compared to non-irradiated rats. Radiation also resulted in an increase (PACF compared to the corn oil treatment. Dietary pectin significantly increased (P=0.0204) the apoptotic index compared to cellulose treatment. These data suggest that ionizing radiation can work synergistically with AOM and increase the formation of high-multiplicity ACF, upregulate cellular proliferation and decrease apoptosis in colonocytes. The data also suggest that diets containing fish oil and pectin may protect against colon cancer by increasing apoptosis and reducing the formation of high multiplicity ACF.

Mann, John Clifford

2005-08-01T23:59:59.000Z

75

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

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

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

76

Methylation of the ATM promoter in glioma cells alters ionizing radiation sensitivity  

SciTech Connect

Glioblastomas are among the malignancies most resistant to radiation therapy. In contrast, cells lacking the ATM protein are highly sensitive to ionizing radiation. The relationship between ATM protein expression and radiosensitivity in 3 glioma cell lines was examined. T98G cells exhibited normal levels of ATM protein, whereas U118 and U87 cells had significantly lower levels of ATM and increased (>2-fold) sensitivity to ionizing radiation compared to T98G cells. The ATM promoter was methylated in U87 cells. Demethylation by azacytidine treatment increased ATM protein levels in the U87 cells and decreased their radiosensitivity. In contrast, the ATM promoter in U118 cells was not methylated. Further, expression of exogenous ATM did not significantly alter the radiosensitivity of U118 cells. ATM expression is therefore heterogeneous in the glioma cells examined. In conclusion, methylation of the ATM promoter may account for the variable radiosensitivity and heterogeneous ATM expression in a fraction of glioma cells.

Roy, Kanaklata [Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Harvard Medical School, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA 02115 (United States); Wang, Lilin [Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Harvard Medical School, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA 02115 (United States); Makrigiorgos, G. Mike [Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Harvard Medical School, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA 02115 (United States); Price, Brendan D. [Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Harvard Medical School, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA 02115 (United States)]. E-mail: brendan_price@dfci.harvard.edu

2006-06-09T23:59:59.000Z

77

Quantitative Phosphoproteomics Identifies Filaggrin and other Targets of Ionizing Radiation in a Human Skin Model  

Science Conference Proceedings (OSTI)

Our objective here was to perform a quantitative phosphoproteomic study on a reconstituted human skin tissue to identify low and high dose ionizing radiation dependent signaling in a complex 3-dimensional setting. Application of an isobaric labeling strategy using sham and 3 radiation doses (3, 10, 200 cGy) resulted in the identification of 1113 unique phosphopeptides. Statistical analyses identified 151 phosphopeptides showing significant changes in response to radiation and radiation dose. Proteins responsible for maintaining skin structural integrity including keratins and desmosomal proteins (desmoglein, desmoplakin, plakophilin 1 and 2,) had altered phosphorylation levels following exposure to both low and high doses of radiation. A phosphorylation site present in multiple copies in the linker regions of human profilaggrin underwent the largest fold change. Increased phosphorylation of these sites coincided with altered profilaggrin processing suggesting a role for linker phosphorylation in human profilaggrin regulation. These studies demonstrate that the reconstituted human skin system undergoes a coordinated response to ionizing radiation involving multiple layers of the stratified epithelium that serve to maintain skin barrier functions and minimize the damaging consequences of radiation exposure.

Yang, Feng; Waters, Katrina M.; Webb-Robertson, Bobbie-Jo M.; Sowa, Marianne B.; Freiin von Neubeck, Claere H.; Aldrich, Joshua T.; Markillie, Lye Meng; Wirgau, Rachel M.; Gristenko, Marina A.; Zhao, Rui; Camp, David G.; Smith, Richard D.; Stenoien, David L.

2012-04-17T23:59:59.000Z

78

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

E-Print Network (OSTI)

for publication 30 October 2007; published 22 April 2008 Laser exposure limits as promulgated by the International at the international level by ICNIRP the International Commission on Non-Ionizing Radiation Protection.1,2 OtherReview of exposure limits and experimental data for corneal and lenticular damage from short pulsed

79

Genetic susceptibility to low-dose ionizing radiation in the mouse mammary  

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

Genetic susceptibility to low-dose ionizing radiation in the mouse mammary Genetic susceptibility to low-dose ionizing radiation in the mouse mammary gland as a means of understanding human risk for breast cancer Antoine M. Snijders Lawrence Berkeley National Laboratory Abstract Goal: Our goal is to develop an in vivo mechanistic model of genetic variation in the low-dose damage responses of mammary glands using inbred mice known to vary in their sensitivity to low-dose induced mammary gland cancer, and to develop molecular predictors for susceptibility or resistance to low-dose induced breast cancer. Background and Significance: It is increasingly believed that individuals differ in their genetic susceptibilities to environmental insults for diseases such as cancer. This concern is especially important for the large numbers of individuals receiving low-dose exposures in the nuclear energy

80

Cosmological constraints in the presence of ionizing and resonance radiation at recombination  

E-Print Network (OSTI)

With the recent measurement of full sky cosmic microwave background polarization from WMAP, key cosmological degeneracies have been broken, allowing tighter constraints to be placed on cosmological parameters inferred assuming a standard recombination scenario. Here we consider the effect on cosmological constraints if additional ionizing and resonance radiation sources are present at recombination. We find that the new CMB data significantly improve the constraints on the additional radiation sources, with $\\log_{10}[\\epsilon_{\\alpha}] < -0.5$ and $\\log_{10}[\\epsilon_{i}] <-2.4$ at 95% c.l. for resonance and ionizing sources respectively. Including the generalized recombination scenario, however, we find that the constraints on the scalar spectral index $n_s$ are weakened to $n_s=0.98\\pm0.03$, with the $n_s=1$ case now well inside the 95% c.l.. The relaxation of constraints on tensor modes, scale invariance, dark energy and neutrino masses are also discussed.

Rachel Bean; Alessandro Melchiorri; Joe Silk

2007-01-09T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

Technical specifications manual for the MARK-1 pulsed ionizing radiation detection system. Volume 1  

Science Conference Proceedings (OSTI)

The MARK-1 detection system was developed by the Idaho National Engineering Laboratory for the US Department of Energy Office of Arms Control and Nonproliferation. The completely portable system was designed for the detection and analysis of intense photon emissions from pulsed ionizing radiation sources. This manual presents the technical design specifications for the MARK-1 detection system and was written primarily to assist the support or service technician in the service, calibration, and repair of the system. The manual presents the general detection system theory, the MARK-1 component design specifications, the acquisition and control software, the data processing sequence, and the system calibration procedure. A second manual entitled: Volume 2: Operations Manual for the MARK-1 Pulsed Ionizing Radiation Detection System (USDOE Report WINCO-1108, September 1992) provides a general operational description of the MARK-1 detection system. The Operations Manual was written primarily to assist the field operator in system operations and analysis of the data.

Lawrence, R.S.; Harker, Y.D.; Jones, J.L.; Hoggan, J.M.

1993-03-01T23:59:59.000Z

82

Asymptotically-Equal-To 10 eV ionization shift in Ir K{alpha}{sub 2} from a near-coincident Lu K-edge  

SciTech Connect

Close to an x-ray filter's K-edge the transmission depends strongly on the photon energy. For a few atom pairs, the K-edge of one is only a few tens of eV higher than a K-line energy of another, so that a small change in the line's energy becomes a measurable change in intensity behind such a matching filter. Lutetium's K-edge is Asymptotically-Equal-To 27 eV above iridium's K{alpha}{sub 2} line, Asymptotically-Equal-To 63.287 keV for cold Ir. A Lu filter reduces this line's intensity by Asymptotically-Equal-To 10 % when it is emitted by a plasma, indicating an ionization shift {Delta}E Asymptotically-Equal-To 10{+-}1 eV.

Pereira, N. R. [Ecopulse, Inc, P.O. Box 528, Springfield, Virginia 22150 (United States); Weber, B. V.; Phipps, D.; Schumer, J. W. [Naval Research Laboratory, Washington, DC 20375 (United States); Seely, J. F. [Artep Inc., 2922 Excelsior Springs Ct, Ellicott City, Maryland 21042 (United States); Carroll, J. J. [Army Research Laboratory, Adelphi, Maryland 20873 (United States); VanHoy, J. R. [United States Naval Academy, Annapolis, Maryland 21402 (United States); Slabkowska, K.; Polasik, M. [Faculty of Chemistry, Nicolaus Copernicus University, Gagarina 7, 87-100 Torun (Poland)

2012-10-15T23:59:59.000Z

83

Exposure to ionizing radiation in the emergency department from commonly performed portable radiographs  

SciTech Connect

To accurately assess the potential hazard of exposure to ionizing radiation from portable radiographs taken in the emergency department, a study was performed to measure such radiation at different distances from the edge of an irradiated field during portable cervical-spine (pC-S), portable chest radiograph (pCXR), and portable anteroposterior-pelvis (pAP-pelvis) radiographs. For all three types of portable radiographs, radiation exposure is a function of distance from the beam. However, at 40 cm (15 inches) away from the beam during a pC-S or pCXR and at 160 cm (63 inches) from a pAP-pelvis film, exposure is minimal. At these distances one would need to be exposed to more than 1,200 such radiographs to equal background environmental ionizing radiation. Medical personnel should not have to leave a patient care area for fear of undue acute and chronic radiation exposure while portable radiographs are performed in the ED. By using protective garments and standing appropriate distances away from the patient, continuous patient care can be maintained while portable radiographs are taken in the ED.

Grazer, R.E.; Meislin, H.W.; Westerman, B.R.; Criss, E.A.

1987-04-01T23:59:59.000Z

84

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

E-Print Network (OSTI)

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

Keast, Craig L.

85

POSITION STATEMENT DOCUMENTING IONIZING RADIATION EXPOSURE IN THE ELECTRONIC HEALTH RECORD  

E-Print Network (OSTI)

IEEE-USA believes that maintaining an accurate record of a patients cumulative exposure to ionizing radiation can be of substantial value for clinical, health services management and research purposes. Excessive radiation can cause cancer, skin and bone marrow disease and a variety of other diseases. Radiation exposure can come from a number of sources, both natural and manmade. Over the lifetime of the individual, medical procedures, such as X-rays, Computed Tomography (CT) scans, and isotope radiation therapy, contribute significant radiation dosages. Monitoring the use of radiological procedures, measuring the radiation dose directly, and recording the dose in the Electronic Health Record (EHR) can help assess and reduce the risk posed by excessive radiation while optimizing the diagnostic value of these procedures. With these risks and benefits in mind, IEEE-USA recommends the following: 1. Health Level Seven International (HL7), the global authority responsible for standards for interoperability of health information technology, should add the appropriate "dose object " radiation parameters, as defined in the IHE Radiology Technical Framework Supplement, Radiation Exposure Monitoring (REM), to HL7/CDA format longitudinal electronic health records (EHRs), to create a longitudinal record of a patient's exposure to radiation resulting from medical procedures. These records should note both the procedure and estimated radiation dose from each procedure. 2. The Office of the National Coordinator for Health Information Technology (ONCHIT) should make radiation dose monitoring a part of meaningful use criteria for EHRs. 3. Healthcare accreditation organizations (JCAHO, NCQA and URAC), in collaboration with the American College of Radiologists (ACR), should continue

Adopted The Ieee-usa

2011-01-01T23:59:59.000Z

86

RADIATION MONITOR CONTAINING TWO CONCENTRIC IONIZATION CHAMBERS AND MEANS FOR INSULATING THE SEPARATE CHAMBERS  

DOE Patents (OSTI)

This invention relates to a portable radiation monitor containing two concentric ionization chambers which permit the use of standard charging and reading devices. It is particularly adapted as a personnel x-ray dosimeter and to this end comprises a small thin walled, cylindrical conductor forming an inner energy dependent chamber, a small thin walled, cylindrical conductor forming an outer energy independent chamber, and polymeric insulation means which insulates said chambers from each other and holds the chambers together with exposed connections in a simple, trouble-free, and compact assembly substantially without variation in directional response. (AEC)

Braestrup, C.B.; Mooney, R.T.

1964-01-21T23:59:59.000Z

87

Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Application to p53 and Low Dose Ionizing Radiation.  

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

Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Application to p53 and Low Dose Ionizing Radiation. Krassimira Botcheva, John J. Dunn and Carl W. Anderson Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA The effects of exposure to low doses of ionizing radiation on humans results largely from changes in gene expression mediated by the activation of sequence-specific DNA binding proteins (transcription factors) as well as changes to other chromosomal proteins and perhaps to DNA. To develop a molecular understanding of the consequences of exposures to low doses of ionizing radiation, it will be necessary to understanding where radiation-activated transcription factors bind in whole genomes and how

88

Induction of nuclear factor kB after low-dose ionizing radiation involves a reactive oxygen intermediate signaling pathway  

Science Conference Proceedings (OSTI)

Reactive oxygen intermediates (ROIs) have been found to be the messengers in the activation of the kB transcription regulator in mitogen- or cytokine-stimulated cells, operating in conjunction with or independently of various other mechanisms; these include Ca{sup ++}-dependent and PKC-dependent cytoplasmic signaling pathways. We have recently reported that low-dose ionizing radiation induces NF-kB in human lymphoblastoid 244B cells. Since ionizing radiation generates free radicals in cells, we have investigated whether the ROIs generated by ionizing radiation induce NF-kB activity, and also whether they do so by a similar mechanism as in cells treated with PMA or H{sub 2}O{sub 2}. The results not only confirm a previous observation from our laboratory that low-dose ionizing radiation (0.1-2.0 Gy) activates kB transcription factor transiently with a maximal induction at 0.5 Gy exposure, but also demonstrate mechanistically that the activation of NF-kB by low-dose ionizing radiation can be inhibited considerably by the antioxidant N-acetyl-L-cysteine, indicating that at least the major part of the activation process is mediated by ROIs. These findings support the idea that ROIs can regulate the kB elements which in turn can serve as response elements for oxidant stress. 37 refs., 4 figs., 1 tab.

Mohan, N.; Meltz, M.L. [Univ. of Texas Health Science Center, San Antonio, TX (United States)

1994-10-01T23:59:59.000Z

89

Alterations in transcription factor binding in radioresistant human melanoma cells after ionizing radiation  

Science Conference Proceedings (OSTI)

We analyzed alterations in transcription factor binding to specific, known promoter DNA consensus sequences between irradiated and unirradiated radioresistant human melanoma (U1-Mel) cells. The goal of this study was to begin to investigate which transcription factors and DNA-binding sites are responsible for the induction of specific transcripts and proteins after ionizing radiation. Transcription factor binding was observed using DNA band-shift assays and oligonucleotide competition analyses. Confluence-arrested U1-Mel cells were irradiated (4.5 Gy) and harvested at 4 h. Double-stranded oligonucleotides containing known DNA-binding consensus sites for specific transcription factors were used. Increased DNA binding activity after ionizing radiation was noted with oligonucleotides containing the CREB, NF-kB and Sp1 consensus sites. No changes in protein binding to AP-1, AP-2, AP-3, or CTF/NF1, GRE or Oct-1 consensus sequences were noted. X-ray activation of select transcription factors, which bind certain consensus sites in promoters, may cause specific induction or repression of gene transcription. 22 refs., 2 figs.

Sahijdak, W.M.; Yang, Chin-Rang; Zuckerman, J.S.; Meyers, M.; Boothman, D.A. [Univ. of Wisconsin, Madison, WI (United States)

1994-04-01T23:59:59.000Z

90

Examination system utilizing ionizing radiation and a flexible, miniature radiation detector probe  

DOE Patents (OSTI)

An optimized examination system and method based on the Reverse Geometry X-Ray.RTM. (RGX.RTM.) radiography technique are presented. The examination system comprises a radiation source, at least one flexible, miniature radiation detector probe positioned in appropriate proximity to the object to be examined and to the radiation source with the object located between the source and the probe, a photodetector device attachable to an end of the miniature radiation probe, and a control unit integrated with a display device connected to the photodetector device. The miniature radiation detector probe comprises a scintillation element, a flexible light guide having a first end optically coupled to the scintillation element and having a second end attachable to the photodetector device, and an opaque, environmentally-resistant sheath surrounding the flexible light guide. The probe may be portable and insertable, or may be fixed in place within the object to be examined. An enclosed, flexible, liquid light guide is also presented, which comprises a thin-walled flexible tube, a liquid, preferably mineral oil, contained within the tube, a scintillation element located at a first end of the tube, closures located at both ends of the tube, and an opaque, environmentally-resistant sheath surrounding the flexible tube. The examination system and method have applications in non-destructive material testing for voids, cracks, and corrosion, and may be used in areas containing hazardous materials. In addition, the system and method have applications for medical and dental imaging.

Majewski, Stanislaw (Grafton, VA); Kross, Brian J. (Yorktown, VA); Zorn, Carl J. (Yorktown, VA); Majewski, Lukasz A. (Grafton, VA)

1996-01-01T23:59:59.000Z

91

Examination system utilizing ionizing radiation and a flexible, miniature radiation detector probe  

DOE Patents (OSTI)

An optimized examination system and method based on the Reverse Geometry X-Ray{trademark} (RGX{trademark}) radiography technique are presented. The examination system comprises a radiation source, at least one flexible, miniature radiation detector probe positioned in appropriate proximity to the object to be examined and to the radiation source with the object located between the source and the probe, a photodetector device attachable to an end of the miniature radiation probe, and a control unit integrated with a display device connected to the photodetector device. The miniature radiation detector probe comprises a scintillation element, a flexible light guide having a first end optically coupled to the scintillation element and having a second end attachable to the photodetector device, and an opaque, environmentally-resistant sheath surrounding the flexible light guide. The probe may be portable and insertable, or may be fixed in place within the object to be examined. An enclosed, flexible, liquid light guide is also presented, which comprises a thin-walled flexible tube, a liquid, preferably mineral oil, contained within the tube, a scintillation element located at a first end of the tube, closures located at both ends of the tube, and an opaque, environmentally-resistant sheath surrounding the flexible tube. The examination system and method have applications in non-destructive material testing for voids, cracks, and corrosion, and may be used in areas containing hazardous materials. In addition, the system and method have applications for medical and dental imaging. 5 figs.

Majewski, S.; Kross, B.J.; Zorn, C.J.; Majewski, L.A.

1996-10-22T23:59:59.000Z

92

Development and characterization of acrylated palm oil nanoparticles using ionizing radiation  

SciTech Connect

In this study, the utilization of radiation crosslinking methods which are known as intermolecular and intramolecular crosslinking for the formation of nanoparticles of Acrylated Palm Oil (APO) in the microemulsion system that also consists of Pluronic F-127 (PF-127) surfactant was demonstrated. This microemulsion system was subjected to the ionizing radiation i.e. gamma irradiation at different doses to form the crosslinked APO nanoparticles. The effects of radiation doses on the size of APO nanoparticles were investigated using the Dynamic Light Scattering (DLS) method and their images were viewed using the Transmission Electron Microcrospy (TEM). The Fourier Transform Infra-Red (FTIR) spectroscopy was used to characterize the chemical structure and the crosslinking conversion of carbon-carbon double bond (-C = C-) of the APO nanoparticles after irradiation. As a result, the size of the APO nanoparticle decreased when the irradiation dose increased. Reduce in size might be due to the effect of intramolecular crosslinking reaction of the APO nanoparticles during irradiation process. Meanwhile, the intramolecular -C C- crosslinking conversion percentage was increased at doses below 1kGy before decreasing at the higher dose that might due to the intermolecular crosslinking of the macromolecules. This study showed that radiation crosslinking methods of polymerization and crosslinking in the microemulsion were found to be promising for the synthesis of nanoparticles.

Tajau, Rida; Yunus, Wan Md Zin Wan; Dahlan, Khairul Zaman Mohd; Mahmood, Mohd Hilmi; Hashim, Kamaruddin [Malaysian Nuclear Agency (Nuclear Malaysia), Radiation Processing Technology Division (BTS), Bangi, 43000 Kajang, Selangor (Malaysia); Chemistry Department, Faculty of Science, University Putra Malaysia (UPM), 43400 UPM Serdang, Selangor (Malaysia); Malaysian Nuclear Agency (Nuclear Malaysia), Radiation Processing Technology Division (BTS), Bangi, 43000 Kajang, Selangor (Malaysia)

2012-11-27T23:59:59.000Z

93

Parameterizations for Water Vapor IR Radiative Transfer in Both the Middle and Lower Atmospheres  

Science Conference Proceedings (OSTI)

Water vapor contributes a maximum of 1C/day to the middle atmospheric thermal infrared (IR) cooling. This magnitude is small but not negligible. Because of the small amount of mass involved and the extremely narrow molecular absorption lines at ...

Ming-Dah Chou; William L. Ridgway; Michael M-H. Yan

1995-04-01T23:59:59.000Z

94

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

Science Conference Proceedings (OSTI)

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

Rosie Howard; Roland Stull

2013-07-01T23:59:59.000Z

95

Carcinogenesis and low-level ionizing radiation with special reference to lung cancer and exposure to radon daughters  

SciTech Connect

Of the important health effects of ionizing radiation, three important late effects - carcinogenesis, teratogenesis and mutagenesis are of greatest concern. This is because any exposure, even at low levels, carries some risk of such deleterious effects. As the dose of radiation increases above very low levels, the risk of health effects increases. Cancer-induction is the most important late somatic effect of low-dose ionizing radiation. Solid cancers, rather than leukemia, are principal late effects in exposed individuals. Tissues vary greatly in their susceptibility to radiation carcinogenesis. The most frequently occurring radiation-induced cancers in man include, in decreasing order of susceptibility: the female breast, the thyroid gland, the blood-forming tissues, the lung, certain organs of the gastrointestinal tract, and the bones. A number of biological and physical factors affect the cancer risk, such as age, sex, life-style, LET, and RBE. Despite uncertainty about low-level radiation risks, regulatory and advisory bodies must set standards for exposure, and individuals need information to be able to make informed judgments for themselves. From the point of view of the policy maker, the overriding concern is the fact that small doses of radiation can cause people to have more cancers than would otherwise be expected. While concern for all radiation effects exists, our human experience is limited to cancer-induction in exposed populations. This discussion is limited to cancer risk estimation and decision-making in relation to the health effects on populations of exposure to low levels of ionizing radiation. Here, low-level radiation will refer to yearly whole-body doses up to 5 rems or 0.05 Sv, or to cumulative doses up to 50 rems or 0.5 Sv from low-LET radiation and from high-LET radiation. (ERB)

Fabrikant, J.I.

1982-04-01T23:59:59.000Z

96

Genome Wide Evaluation of Normal Human Tissue in Response to Controlled, In vivo Low-Dose Low LET Ionizing Radiation Exposure: Pathways and Mechanisms Final Report, September 2013  

SciTech Connect

During course of this project, we have worked in several areas relevant to low-dose ionizing radiation. Using gene expression to measure biological response, we have examined the response of human skin exposed in-vivo to radation, human skin exposed ex-vivo to radiation, and a human-skin model exposed to radiation. We have learned a great deal about the biological response of human skin to low-dose ionizing radiation.

Rocke, David M. [University of California Davis

2013-09-09T23:59:59.000Z

97

Mitochondrial-Derived Oxidants and Cellular Responses to Low Dose/Low LET Ionizing Radiation  

SciTech Connect

Exposure to ionizing radiation results in the immediate formation of free radicals and other reactive oxygen species (ROS). It has been assumed that the subsequent injury processes leading to genomic instability and carcinogenesis following radiation, derive from the initial oxidative damage caused by these free radicals and ROS. It is now becoming increasingly obvious that metabolic oxidation/reduction (redox) reactions can be altered by irradiation leading to persistent increases in steady-state levels of intracellular free radicals and ROS that contribute to the long term biological effects of radiation exposure by causing chronic oxidative stress. The objective during the last period of support (DE-FG02-05ER64050; 5/15/05-12/31/09) was to determine the involvement of mitochondrial genetic defects in metabolic oxidative stress and the biological effects of low dose/low LET radiation. Aim 1 was to determine if cells with mutations in succinate dehydrogenase (SDH) subunits C and D (SDHC and SDHD in mitochondrial complex II) demonstrated increases in steady-state levels of reactive oxygen species (ROS; O2- and H2O2) as well as demonstrating increased sensitivity to low dose/low LET radiation (10 cGy) in cultured mammalian cells. Aim #2 was to determine if mitochondrially-derived ROS contributed to increased sensitivity to low dose/low LET radiation in mammalian cells containing mutations in SDH subunits. Aim #3 was to determine if a causal relationship existed between increases in mitochondrial ROS production, alterations in electron transport chain proteins, and genomic instability in the progeny of irradiated cells. Evidence gathered in the 2005-2009 period of support demonstrated that mutations in genes coding for mitochondrial electron transport chain proteins (ETC); either Succinate Dehydrogenase (SDH) subunit C (SDHC) or subunit D (SDHD); caused increased ROS production, increased genomic instability, and increased sensitivity to low dose/low LET radiation that could be mitigated by over expression of the H2O2 metabolizing enzyme, catalase, and/or the mitochondrial form of superoxide dismutase (MnSOD). Furthermore, using radiation-induced genomically unstable cells, it was shown that steady-state levels of H2O2 were significantly elevated for many cell generations following exposure, catalase suppressed the radiation-induced mutator phenotype when added long after radiation exposure, unstable clones showed evidence of mitochondrial dysfunction some of which was characterized by improper assembly of SDH subunits (particularly subunit B), and chemical inhibitors of SDH activity could decrease steady-state levels of H2O2 as well as mutation frequency. These results support the hypotheses that 1) SDH mutations could contribute to transformation by inducing genomic instability and a mutator phenotype via increasing steady-state levels of ROS; 2) metabolic sources of O2- and H2O2 play a significant role in low dose radiation induced injury and genomic instability; and 3) increased mutation rates in irradiated mammal cells can be suppressed by scavengers of H2O2 (particularly catalase) long after radiation exposure. Overall the results obtained during this period of support provide clear evidence in support of the hypothesis that abnormal oxidative metabolism in mitochondria that result in increases in steady-sate levels of H2O2 and other ROS are capable of significantly contributing to radiation-induced mutator phenotypes in mammalian cells.

Spitz, Douglas R.

2009-11-09T23:59:59.000Z

98

TWO-DIMENSIONAL RADIATIVE MAGNETOHYDRODYNAMIC SIMULATIONS OF THE IMPORTANCE OF PARTIAL IONIZATION IN THE CHROMOSPHERE  

Science Conference Proceedings (OSTI)

The bulk of the solar chromosphere is weakly ionized and interactions between ionized particles and neutral particles likely have significant consequences for the thermodynamics of the chromospheric plasma. We investigate the importance of introducing neutral particles into the MHD equations using numerical 2.5D radiative MHD simulations obtained with the Bifrost code. The models span the solar atmosphere from the upper layers of the convection zone to the low corona, and solve the full MHD equations with non-gray and non-LTE radiative transfer, and thermal conduction along the magnetic field. The effects of partial ionization are implemented using the generalized Ohm's law, i.e., we consider the effects of the Hall term and ambipolar diffusion in the induction equation. The approximations required in going from three fluids to the generalized Ohm's law are tested in our simulations. The Ohmic diffusion, Hall term, and ambipolar diffusion show strong variations in the chromosphere. These strong variations of the various magnetic diffusivities are absent or significantly underestimated when, as has been common for these types of studies, using the semi-empirical VAL-C model as a basis for estimates. In addition, we find that differences in estimating the magnitude of ambipolar diffusion arise depending on which method is used to calculate the ion-neutral collision frequency. These differences cause uncertainties in the different magnetic diffusivity terms. In the chromosphere, we find that the ambipolar diffusion is of the same order of magnitude or even larger than the numerical diffusion used to stabilize our code. As a consequence, ambipolar diffusion produces a strong impact on the modeled atmosphere. Perhaps more importantly, it suggests that at least in the chromospheric domain, self-consistent simulations of the solar atmosphere driven by magnetoconvection can accurately describe the impact of the dominant form of resistivity, i.e., ambipolar diffusion. This suggests that such simulations may be more realistic in their approach to the lower solar atmosphere (which directly drives the coronal volume) than previously assumed.

Martinez-Sykora, Juan; De Pontieu, Bart; Hansteen, Viggo, E-mail: j.m.sykora@astro.uio.no [Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304 (United States)

2012-07-10T23:59:59.000Z

99

A dedicated storage ring for Far-IR coherent synchrotron radiation at the ALS  

E-Print Network (OSTI)

SYNCHROTRON RADIATION AT THE ALS* W. C. Barry, K. M.on the Infrared Beamline ALS 1999 Activity Report pp. 78-m circumference ring will use the ALS injector parasitically

2002-01-01T23:59:59.000Z

100

Ionization of Sodium and Rubidium nS, nP and nD Rydberg atoms by blackbody radiation  

E-Print Network (OSTI)

Results of theoretical calculations of ionization rates of Rb and Na Rydberg atoms by blackbody radiation (BBR) are presented. Calculations have been performed for nS, nP and nD states of Na and Rb, which are commonly used in a variety of experiments, at principal quantum numbers n=8-65 and at three ambient temperatures of 77, 300 and 600 K. A peculiarity of our calculations is that we take into account the contributions of BBR-induced redistribution of population between Rydberg states prior to photoionization and field ionization by extraction electric field pulses. The obtained results show that these phenomena affect both the magnitude of measured ionization rates and shapes of their dependencies on n. The calculated ionization rates are compared with the results of our earlier measurements of BBR-induced ionization rates of Na nS and nD Rydberg states with n=8-20 at 300 K. A good agreement for all states except nS with n>15 is observed. We also present the useful analytical formulae for quick estimation of BBR ionization rates of Rydberg atoms.

I. I. Beterov; D. B. Tretyakov; I. I. Ryabtsev; A. Ekers; N. N. Bezuglov

2007-02-22T23:59:59.000Z

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101

Gaseous Radiochemical Method for Registration of Ionizing Radiation and Its Possible Applications in Science and Industry  

E-Print Network (OSTI)

This work presents a new possibility of registration of ionizing radiation by the flowing gaseous radiochemical method (FGRM). The specified method uses the property of some solid crystalline lattice materials for a free emission of radioactive isotopes of inert gas atoms formed as a result of nuclear reactions. Generated in an ampoule of the detector, the radioactive inert gases are transported by a gas-carrier into the proportional gas counter of the flowing type, where the decay rate of the radioactive gas species is measured. This quantity is unequivocally related to the flux of particles (neutrons, protons, light and heavy ions) at the location of the ampoule. The method was used to monitor the neutron flux of the pulsed neutron target "RADEX" driven by the linear proton accelerator of INR RAS. Further progress of the FGRM may give rise to possible applications in nuclear physics, astrophysics and medicine, in the nondestructive control of fissionable materials, diagnostics of thermonuclear plasma, monitoring of fluxes and measurement of spectra of bombarding particles.

S. G. Lebedev; V. E. Yants

2005-10-06T23:59:59.000Z

102

Ionizing radiation induces IL-6-production by human fibroblasts involving activation of nuclear factor-. kappa. B  

Science Conference Proceedings (OSTI)

The authors report that human lung fibroblasts respond to X-ray treatment with release of interleukin (IL) -6. Synthesis of IL-6 upon ionizing radiation is preceded by an increase of IL-6 transcript levels resulting from transcriptional activation of the IL-6 gene. Analysis of deleted fragments of the IL-6 promoter revealed that transcriptional induction of the IL-6 promoter is due to enhanced binding activity of the transcription factor NF-kB. Although AP-1 does not participate in the rapid induction of the IL-6 promoter its binding activity is also enhanced upon XRT. In contrast to binding kinetics observed with NF-kB, AP-1 binding upon XRT. In contrast to binding kinetics observed with NF-kB- and the AP-1 recognition sequence, conferred inducibility by XRT to a heterologous promoter, with reporter gene activity being maximal 24 hours or 48 hours upon XRT, respectively. Sequential activation of two distinct transcription factors might thus contribute to synchronize transcriptional activation of different genes participating in the X-ray response.

Brach, M.A.; Gruss, H.J.; Kaisho, Tsuneyasu; Asano, Yoshinobu; Vos, Sven de; Mertelsmann, R.; Hirano, Toshio; Herrmann, F. (Univ. of Freiburg (Germany) Osaka Univ. (Japan))

1992-02-26T23:59:59.000Z

103

Ionization of Sodium and Rubidium nS, nP and nD Rydberg atoms by blackbody radiation  

E-Print Network (OSTI)

Results of theoretical calculations of ionization rates of Rb and Na Rydberg atoms by blackbody radiation (BBR) are presented. Calculations have been performed for nS, nP and nD states of Na and Rb, which are commonly used in a variety of experiments, at principal quantum numbers n=8-65 and at three ambient temperatures of 77, 300 and 600 K. A peculiarity of our calculations is that we take into account the contributions of BBR-induced redistribution of population between Rydberg states prior to photoionization and field ionization by extraction electric field pulses. The obtained results show that these phenomena affect both the magnitude of measured ionization rates and shapes of their dependencies on n. The calculated ionization rates are compared with the results of our earlier measurements of BBR-induced ionization rates of Na nS and nD Rydberg states with n=8-20 at 300 K. A good agreement for all states except nS with n>15 is observed. We also present the useful analytical formulae for quick estimation ...

Beterov, I I; Ekers, A; Ryabtsev, I I; Tretyakov, D B

2007-01-01T23:59:59.000Z

104

European Integrated Project RISC-RAD Radiosensitivity of Individuals and Susceptibility to Cancer induced by Ionizing Radiations  

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

Integrated Project RISC-RAD Integrated Project RISC-RAD Radiosensitivity of Individuals and Susceptibility to Cancer induced by Ionizing Radiations Laure Sabatier 1 , L.H.F Mullenders 2 , Mike Atkinson 3 , Simon Bouffler 4 , Herwig Paretzke 5 1 Laboratory of Radiobiology and Oncology, CEA, 18 route du panorama BP6 92265 Fontenay-aux- Roses, France 2 LUMC, Department of Toxicogenetics, Postal Zone S-4-P, P.O. Box 9600, 2300 RC Leiden, The Netherlands 3 GSF- Institute of Pathology, Ingolstädter Landstrasse 1, 85764 Neuherberg Germany 4 HPA Radiation Protection Division, Centre for Radiation Chemical and Environmental Hazards, Chilton, UK 5 GSF- Institute of Radiation Protection, Ingolstädter Landstrasse 1, Neuherberg, D-85764 Germany In radiological protection, the risks of inducing stochastic health effects (largely cancer) by a

105

Raman spectroscopy of tumour cells exposed to clinically relevant doses of ionizing radiation.  

E-Print Network (OSTI)

??Improvements to radiation therapy treatment outcomes rely, in part, on consideration of patient specific radiosensitivity. Therefore an assay which quantifies radiation-induced biochemical changes, and subsequently (more)

Harder, Samantha

2013-01-01T23:59:59.000Z

106

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

Science Conference Proceedings (OSTI)

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

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

2011-04-30T23:59:59.000Z

107

IONIZATION CHAMBER  

DOE Patents (OSTI)

This patent describes a novel ionization chamber which is well suited to measuring the radioactivity of the various portions of a wire as the wire is moved at a uniform speed, in order to produce the neutron flux traverse pattern of a reactor in which the wire was previously exposed to neutron radiation. The ionization chamber of the present invention is characterized by the construction wherein the wire is passed through a tubular, straight electrode and radiation shielding material is disposed along the wire except at an intermediate, narrow area where the second electrode of the chamber is located.

Redman, W.C.; Shonka, F.R.

1958-02-18T23:59:59.000Z

108

Activation of nuclear factor kB in human lymphoblastoid cells by low-dose ionizing radiation  

SciTech Connect

Nuclear factor kB (NF-kB) is a pleiotropic transcription factor which is involved in the transcriptional regulation of several specific genes. Recent reports demonstrated that ionizing radiation in the dose range of 2-50 Gy results in expression of NF-kB in human KG-1 myeloid leukemia cells and human B-lymphocyte precursor cells; the precise mechanism involved and the significance are not yet known. The present report demonstrates that even lower doses of ionizing radiation, 0.25-2.0 Gy, are capable of inducing expression of NF-kB in EBV-transformed 244B human lymphoblastoid cells. These results are in a dose range where the viability of the cells remains very high. After exposure to {sup 137}Cs {gamma} rays at a dose rate of 1.17 Gy/min, a maximum in expression of NF-kB was seen at 8 h after a 0.5-Gy exposure. Time-course studies revealed a biphasic time-dependent expression after 0.5-, 1- and 2-Gy exposures. However, for each time examined, the expression of NF-kB was maximum after the 0.5-Gy exposure. The expression of the p50 and p65 NF-kB subunits was also shown to be regulated differentially after exposures to 1.0 and 2.0 Gy. 32 refs., 3 figs.

Prasad, A.V.; Mohan, N.; Meltz, M.L.; Chandrasekar, B. [Univ. of Texas Health Science Center, San Antonio, TX (United States)

1994-06-01T23:59:59.000Z

109

Spectral energy distribution of the metagalactic ionizing radiation field from QSO absorption spectra  

E-Print Network (OSTI)

A computational procedure is presented to estimate the spectral shape of the ionizing background between 1 and 10 Ryd by analyzing optically thin absorption systems in the spectra of high redshift quasars. The procedure is based on the response surface methodology from the theory of experimental design. The shape of the recovered UV background at z~3 shows a significant intensity decrease between 3 and 4 Ryd compared to the metagalactic spectrum of Haardt & Madau (1996). This decrease is interpreted as produced by HeII Gunn-Peterson effect. There are no features indicating a contribution from galaxies to the UV background which is therefore dominated by QSOs at z~3.

I. I. Agafonova; M. Centurion; S. A. Levshakov; P. Molaro

2005-06-07T23:59:59.000Z

110

Low-Dose Ionizing Radiation Alters the Epigenome of the Avy Mouse  

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

Medical Center Abstract Background: Humans have evolved and thrived amidst constant low-dose (0-10 cGy) background radiation exposure from natural sources. Currently, however, the...

111

Ionization chamber  

DOE Patents (OSTI)

An ionization chamber has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionize the gas.

Walenta, Albert H. (Port Jefferson Station, NY)

1981-01-01T23:59:59.000Z

112

ealth physics is concerned with protecting people from the harmful effects of ionizing radiation while allowing its beneficial use in medicine, science,  

E-Print Network (OSTI)

, particularly from medical exposures and from the atomic-bomb ex- posures in Hiroshima and Nagasaki. DuringH ealth physics is concerned with protecting people from the harmful effects of ionizing radiation effects such as cancer that had been observed in populations of people receiv- ing high doses

Massey, Thomas N.

113

Low Dose Ionizing Radiation and HZE Particle Effects on Adult Hippocampal  

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

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

114

Ionizing radiation risks to Satellite Power Systems (SPS) workers in space  

DOE Green Energy (OSTI)

A reference Satellite Power System (SPS) has been designed by NASA and its contractors for the purposes of evaluating the concept and carrying out assessments of the various consequences of development, including those on the health of the space workers. The Department of Energy has responsibility for directing various assessments. Present planning calls for the SPS workers to move from Earth to a low earth orbit (LEO) at an altitude of 500 kilometers; to travel by a transfer ellipse (TE) trajectory to a geosynchronous orbit (GEO) at an altitude of 36,000 kilometers; and to remain in GEO orbit for about 90 percent of the total time aloft. The radiation risks to the health of workers who will construct and maintain solar power satellites in the space environment are studied. The charge to the committee was: (a) to evaluate the radiation environment estimated for the Reference System which could represent a hazard; (b) to assess the possible somatic and genetic radiation hazards; and (c) to estimate the risks to the health of SPS workers due to space radiation exposure, and to make recommendations based on these conclusions. Details are presented. (WHK)

Not Available

1980-12-01T23:59:59.000Z

115

A molecular dynamics simulation of DNA damage induction by ionizing radiation  

E-Print Network (OSTI)

We present a multi-scale simulation of early stage of DNA damages by the indirect action of hydroxyl ($^\\bullet$OH) free radicals generated by electrons and protons. The computational method comprises of interfacing the Geant4-DNA Monte Carlo with the ReaxFF molecular dynamics software. A clustering method was employed to map the coordinates of $^\\bullet$OH-radicals extracted from the ionization track-structures onto nano-meter simulation voxels filled with DNA and water molecules. The molecular dynamics simulation provides the time evolution and chemical reactions in individual simulation voxels as well as the energy-landscape accounted for the DNA-$^\\bullet$OH chemical reaction that is essential for the first principle enumeration of hydrogen abstractions, chemical bond breaks, and DNA-lesions induced by collection of ions in clusters less than the critical dimension which is approximately 2-3 \\AA. We show that the formation of broken bonds leads to DNA base and backbone damages that collectively propagate ...

Abolfath, Ramin M; Chen, Zhe J; Nath, Ravinder

2013-01-01T23:59:59.000Z

116

Protein Kinase CK2 Regulates Cytoskeletal Reorganization during Ionizing Radiation-Induced Senescence of Human Mesenchymal Stem Cells  

SciTech Connect

Human mesenchymal stem cells (hMSC) are critical for tissue regeneration. How hMSC respond to genotoxic stresses and potentially contribute to aging and cancer remain underexplored. We demonstrated that ionizing radiation induced cellular senescence of hMSC over a period of 10 days, showing a critical transition between day 3 and day 6. This was confirmed by senescence-associated beta-galactosidase (SA-{beta}-gal) staining, protein expression profiles of key cell cycle regulators (retinoblastoma (Rb) protein, p53, p21{sup waf1/Cip1}, and p16{sup INK4A}), and senescence-associated secretory phenotypes (SASPs) (IL-8, IL-12, GRO, and MDC). We observed dramatic cytoskeletal reorganization of hMSC through reduction of myosin-10, redistribution of myosin-9, and secretion of profilin-1. Using a SILAC-based phosphoproteomics method, we detected significant reduction of myosin-9 phosphorylation at Ser1943, coinciding with its redistribution. Importantly, through treatment with cell permeable inhibitors (4,5,6,7-tetrabromo-1H-benzotriazole (TBB) and 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole (DMAT)), and gene knockdown using RNA interference, we identified CK2, a kinase responsible for myosin-9 phosphorylation at Ser1943, as a key factor contributing to the radiation-induced senescence of hMSC. We showed that individual knockdown of CK2 catalytic subunits CK2{alpha} and CK2{alpha}{prime} induced hMSC senescence. However, only knockdown of CK2{alpha} resulted in morphological phenotypes resembling those of radiation-induced senescence. These results suggest that CK2{alpha} and CK2{alpha}{prime} play differential roles in hMSC senescence progression, and their relative expression might represent a novel regulatory mechanism for CK2 activity.

Wang, Daojing; Jang, Deok-Jin

2009-08-21T23:59:59.000Z

117

Reduction of Carbon Dioxide inAqueous Solutions by IonizingRadiation  

DOE Green Energy (OSTI)

The question of the conditions under which living matter originated on the surface of the earth is still a subject limited largely to speculation. The speculation has a greater chance of approaching the truth insofar as it includes and is based upon the ever wider variety of established scientific fact. One of the purposes of the herein reported observation was to add another fact to the ever increasing information which might have any bearing upon this most interesting question. It is not our purpose in the present communication to discuss the various proposals or the arguments which have been adduced for and against them. One of the most popular current conceptions is that life originated in an organic milieu on the surface of the earth, (1,2,3,4,5). The problem to which we are addressed is the origin of that organic milieu in the absence of any life. It appeared to us that one source, if not the only source, of reduced carbon compounds in complex arrangements might be the interaction of various high energy radiations with aqueous solutions of inorganic materials, particularly carbon dioxide, and nitrogenous compounds such as ammonia and nitrogen, since it appears that these compounds were the commoner forms in which the essential elements found themselves on the primordial earth. While it has long been known that high energy radiations can cause organic decomposition and oxidation, it seemed useful to us to demonstrate that conditions could be found in which high energy radiations could induce the reduction with water of carbon dioxide and the ultimate creation of polyatomic molecules (other than simple polymerization of monomers) of carbon, oxygen, hydrogen and nitrogen.

Garrison, W.M.; Morrison, D.C.; Hamilton, J.G.; Benson, A.A.; Calvin, M.

1951-03-13T23:59:59.000Z

118

Review Article: Physics and Monte Carlo Techniques as Relevant to Cryogenic, Phonon and Ionization Readout of CDMS Radiation-Detectors  

E-Print Network (OSTI)

This review discusses detector physics and Monte Carlo techniques for cryogenic, radiation detectors that utilize combined phonon and ionization readout. A general review of cryogenic phonon and charge transport is provided along with specific details of the Cryogenic Dark Matter Search detector instrumentation. In particular this review covers quasidiffusive phonon transport, which includes phonon focusing, anharmonic decay and isotope scattering. The interaction of phonons in the detector surface is discussed along with the downconversion of phonons in superconducting films. The charge transport physics include a mass tensor which results from the crystal band structure and is modeled with a Herring Vogt transformation. Charge scattering processes involve the creation of Neganov-Luke phonons. Transition-edge-sensor (TES) simulations include a full electric circuit description and all thermal processes including Joule heating, cooling to the substrate and thermal diffusion within the TES, the latter of which is necessary to model normal-superconducting phase separation. Relevant numerical constants are provided for these physical processes in germanium, silicon, aluminum and tungsten. Random number sampling methods including inverse cumulative distribution function (CDF) and rejection techniques are reviewed. To improve the efficiency of charge transport modeling, an additional second order inverse CDF method is developed here along with an efficient barycentric coordinate sampling method of electric fields. Results are provided in a manner that is convenient for use in Monte Carlo and references are provided for validation of these models.

S. W. Leman

2011-09-06T23:59:59.000Z

119

Genetic susceptibility to low-dose ionizing radiation in the mouse mammary glandas a means of understanding human risk for breast cancer  

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

susceptibility to low-dose ionizing radiation in the mouse mammary gland susceptibility to low-dose ionizing radiation in the mouse mammary gland as a means of understanding human risk for breast cancer Antoine M. Snijders 1 , Francesco Marchetti 1 , Ju Han 1 , Sandhya Bhatnagar 1 , Nadire Duru 1 , Zhi Hu 1 , Jian-Hua Mao 1 , Mina Bissell 1 , Joe Gray 1,2 , Gary H. Karpen 1 , Priscilla K. Cooper 1 and Andrew J. Wyrobek 1 1 Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 2 Current affiliation: Biomedical Engineering, Oregon Health Science Univ, Portland, OR Goal: Our goal is to develop an in vivo mechanistic model of genetic variation in the low-dose damage responses of mammary glands using inbred mice known to vary in their sensitivity to low-dose induced mammary gland cancer, and to develop molecular predictors for susceptibility or resistance to low-dose induced breast cancer.

120

The carcinogenic risks of low-LET and high-LET ionizing radiations  

SciTech Connect

New information is available concerning the carcinogenic effects of radiation and the implications for risk assessment and risk management. This information comes from further follow-up of the epidemiological studies of the Japanese atomic bomb survivors, patients irradiated medically for cancer and allied conditions, and workers exposed in various occupations. In the Japanese atomic bomb survivors the carcinogenic risks are estimated to be somewhat higher than previously, due to the reassessment of the atomic-bomb dosimetry, further follow-up with increase in the number of excess cancer deaths, particularly in survivors irradiated early in life, and changes in the methods of analysis to compute the age-specific risks of cancer. Because of the characteristics of the atomic bomb survivor series as regards sample size, age and sex distribution, duration for follow-up, person-years at risk, and type of dosimetry, the mortality experience of the atomic bomb survivors was selected by the UNSCEAR Committee and the BEIR V Committee as the more appropriate basis for projecting risk estimates for the general population. In the atomic bomb survivors, the dose-effect relationship for overall cancer mortality other than leukemia is consistent with linearity below 3 Gy, while the dose-effect relationship for leukemia, excluding chronic lymphatic leukemia, conforms best to a linear-quadratic function. The shape of the dose-incidence curve at low doses still remains uncertain, and the data do not rule out the possible existence of a threshold for an neoplasm. The excess relative risk of mortality from all cancers combined is estimated to be 1.39 per Gy (shielded kerma), which corresponds to an absolute risk of 10.0 excess cancer deaths per 10,000 PYGy; the relative risks is 1.41 at 1 Gy (organ-absorbed dose), and an absolute risk of 13.07 excess cancer deaths per 10,000 PYGy. 19 refs.

Fabrikant, J.I. (Lawrence Berkeley Lab., CA (USA))

1989-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

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

Science Conference Proceedings (OSTI)

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

2009-11-18T23:59:59.000Z

122

IR-2003-  

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

Relations Office Washington, D.C. Media Contact: 202.622.4000 Relations Office Washington, D.C. Media Contact: 202.622.4000 www.IRS.gov/newsroom Public Contact: 800.829.1040 $1 BILLION IN TAX CREDITS ALLOCATED TO CLEAN COAL PROJECTS IR-2006-184, Nov. 30, 2006 WASHINGTON - The Internal Revenue Service announced that it has allocated nearly $1 billion of tax credits to nine planned clean coal projects. The Energy Policy Act of 2005 authorized $1.65 billion in tax credits for clean coal projects. The Act allocated $800 million of credits to integrated gasification combined cycle (IGCC) projects, $500 million to non-IGCC advanced coal electricity generation projects and $350 million to gasification projects. The $800 million allocated to IGCC projects is required to be allocated in relatively equal amounts among bituminous coal,

123

Radiation Physics Division  

Science Conference Proceedings (OSTI)

... The Radiation Physics Division, part of the Physical Measurement Laboratory ... the measurement standards for ionizing radiations and radioactivity ...

2013-09-05T23:59:59.000Z

124

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

E-Print Network (OSTI)

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

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

125

IN-SITU PROBING OF RADIATION-INDUCED PROCESSING OF ORGANICS IN ASTROPHYSICAL ICE ANALOGS-NOVEL LASER DESORPTION LASER IONIZATION TIME-OF-FLIGHT MASS SPECTROSCOPIC STUDIES  

Science Conference Proceedings (OSTI)

Understanding the evolution of organic molecules in ice grains in the interstellar medium (ISM) under cosmic rays, stellar radiation, and local electrons and ions is critical to our understanding of the connection between ISM and solar systems. Our study is aimed at reaching this goal of looking directly into radiation-induced processing in these ice grains. We developed a two-color laser-desorption laser-ionization time-of-flight mass spectroscopic method (2C-MALDI-TOF), similar to matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF) mass spectroscopy. Results presented here with polycyclic aromatic hydrocarbon (PAH) probe molecules embedded in water-ice at 5 K show for the first time that hydrogenation and oxygenation are the primary chemical reactions that occur in astrophysical ice analogs when subjected to Ly{alpha} radiation. We found that hydrogenation can occur over several unsaturated bonds and the product distribution corresponds to their stabilities. Multiple hydrogenation efficiency is found to be higher at higher temperatures (100 K) compared to 5 K-close to the interstellar ice temperatures. Hydroxylation is shown to have similar efficiencies at 5 K or 100 K, indicating that addition of O atoms or OH radicals to pre-ionized PAHs is a barrierless process. These studies-the first glimpses into interstellar ice chemistry through analog studies-show that once accreted onto ice grains PAHs lose their PAH spectroscopic signatures through radiation chemistry, which could be one of the reason for the lack of PAH detection in interstellar ice grains, particularly the outer regions of cold, dense clouds or the upper molecular layers of protoplanetary disks.

Gudipati, Murthy S.; Yang Rui, E-mail: gudipati@jpl.nasa.gov, E-mail: ryang73@ustc.edu [University of Maryland (United States)

2012-09-01T23:59:59.000Z

126

IONIZING RADIATION DOSIMETRY  

E-Print Network (OSTI)

registered certification marks of the National Institute of Standards and Technology and the federal government, who retain exclusive rights to control the use thereof. Permission to use the term and/or logo is granted to NVLAP-accredited laboratories for the limited purposes of announcing their accredited status, and for use on reports that describe only testing and calibration within the scope of accreditation. NIST reserves the right to control the quality of the use of the term NVLAP and of the NVLAP logo. Contents Contents.......................................................................................................................................................iii Foreword.......................................................................................................................................................v

Betty Ann Torres; Carlos M. Gutierrez

2005-01-01T23:59:59.000Z

127

Ionizing Radiation Detector  

Science Conference Proceedings (OSTI)

A CdZnTe (CZT) crystal provided with a native CdO dielectric coating to reduce surface leakage currents and thereby, improve the resolution of instruments incorporating detectors using CZT crystals is disclosed. A two step process is provided for forming the dielectric coating which includes etching the surface of a CZT crystal with a solution of the conventional bromine/methanol etch treatment, and passivating the CZT crystal surface with a solution of 10 w/o NH.sub.4 F and 10 w/o H.sub.2 O.sub.2 in water after attaching electrical contacts to the crystal surface.

Wright, Gomez W. (Nashville, TN); James, Ralph B. (Livermore, CA); Burger, Arnold (Nashville, TN); Chinn, Douglas A. (Livermore, CA)

2003-11-18T23:59:59.000Z

128

Perspectives of Decision-Making and Estimation of Risk in Populations Exposed to Low Levels of Ionizing Radiations  

E-Print Network (OSTI)

exposure to radioactive fallout in radiation-associatedheight of the radioactive fallout deliberations in the early

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

129

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

E-Print Network (OSTI)

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

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

130

Low Dose Radiation Research Program: Computational Modeling of Biochemical  

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

Computational Modeling of Biochemical Pathways Linking Ionizing Computational Modeling of Biochemical Pathways Linking Ionizing Radiation to Cell Cycle Arrest, Apoptosis, and Tumor Incidence Authors: Yuchao Maggie Zhao and Rory Conolly Institutions: Center for Computational Systems Biology CIIT Centers for Health Research Long-Range Goal: To develop an integrated, computational framework for the prediction of low-dose-response to ionizing radiation (IR) in people. Methodology: To provide a flexible framework to evaluate mechanisms of cellular adaptive responses after exposure to IR, three progressively more complicated descriptions of biochemical pathways linking DNA damage with cell-cycle checkpoint control and apoptosis were developed. These descriptions focus on p53-dependent checkpoint arrest and apoptosis, p73-dependent apoptosis, and Chk2-dependent checkpoint arrest,

131

Radiation and Biomolecular Physics Division  

Science Conference Proceedings (OSTI)

... Welcome. The Radiation and Biomolecular Physics Division is a division ... disseminate the national standards for ionizing radiations and radioactivity ...

2012-02-08T23:59:59.000Z

132

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

Science Conference Proceedings (OSTI)

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

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

2010-07-01T23:59:59.000Z

133

Ionization detection system for aerosols  

DOE Patents (OSTI)

This invention relates to an improved smoke-detection system of the ionization-chamber type. In the preferred embodiment, the system utilizes a conventional detector head comprising a measuring ionization chamber, a reference ionization chamber, and a normally non-conductive gas triode for discharging when a threshold concentration of airborne particulates is present in the measuring chamber. The improved system utilizes a measuring ionization chamber which is modified to minimize false alarms and reductions in sensitivity resulting from changes in ambient temperature. In the preferred form of the modification, an annular radiation shield is mounted about the usual radiation source provided to effect ionization in the measuring chamber. The shield is supported by a bimetallic strip which flexes in response to changes in ambient temperature, moving the shield relative to the source so as to vary the radiative area of the source in a manner offsetting temperature-induced variations in the sensitivity of the chamber.

Jacobs, Martin E. (Chillicothe, OH)

1977-01-01T23:59:59.000Z

134

Cell Type-dependent Gene Transcription Profile in Three Dimensional Human Skin Tissue Model Exposed to Low Doses of Ionizing Radiation: Implications for Medical Exposures  

SciTech Connect

The concern over possible health risks from exposures to low doses of ionizing radiation has been driven largely by the increase in medical exposures, the routine implementation of X-ray backscatter devices for airport security screening, and, most recently, the nuclear incident in Japan. Due to a paucity of direct epidemiological data at very low doses, cancer risk must be estimated from high dose exposure scenarios. However, there is increasing evidence that low and high dose exposures result in different signaling events and may have different mechanisms of cancer induction. We have examined the radiation induced temporal response of an in vitro three dimensional (3D) human skin tissue model using microarray-based transcriptional profiling. Our data shows that exposure to 100 mGy of X-rays is sufficient to affect gene transcription. Cell type specific analysis showed significant changes in gene expression with the levels of > 1400 genes altered in the dermis and > 400 genes regulated in the epidermis. The two cell types rarely exhibited overlapping responses at the mRNA level. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) measurements validated the microarray data in both regulation direction and value. Key pathways identified relate to cell cycle regulation, immune responses, hypoxia, reactive oxygen signaling, and DNA damage repair. We discuss in particular the role of proliferation and emphasizing how the disregulation of cellular signaling in normal tissue may impact progression towards radiation induced secondary diseases.

Freiin von Neubeck, Claere H.; Shankaran, Harish; Karin, Norman J.; Kauer, Paula M.; Chrisler, William B.; Wang, Xihai; Robinson, Robert J.; Waters, Katrina M.; Tilton, Susan C.; Sowa, Marianne B.

2012-04-17T23:59:59.000Z

135

Welding arc gap ionization device  

SciTech Connect

An alpha emitting isotope is positioned near the tip of a TIG welding electrode so that the alpha radiation can provide an ionized path between the electrode and the workpiece.

Schweikhardt, George M. (Richland, WA)

1976-01-01T23:59:59.000Z

136

PAH chemistry and IR emission from circumstellar disks  

E-Print Network (OSTI)

Aims. The chemistry of, and infrared (IR) emission from, polycyclic aromatic hydrocarbons (PAHs) in disks around Herbig Ae/Be and T Tauri stars are investigated. The equilibrium distribution of the PAHs over all accessible charge/hydrogenation states depends on the size and shape of the PAHs and on the physical properties of the star and surrounding disk. Methods. A chemistry model is created to calculate this equilibrium distribution. Destruction of PAHs by ultraviolet (UV) photons, possibly in multi-photon absorption events, is taken into account. The chemistry model is coupled to a radiative transfer code to provide the physical parameters and to combine the PAH emission with the spectral energy distribution (SED) from the star+disk system. Results. Normally hydrogenated PAHs in Herbig Ae/Be disks account for most of the observed PAH emission, with neutral and positively ionized species contributing in roughly equal amounts. Close to the midplane, the PAHs are more strongly hydrogenated and negatively ionized, but these species do not contribute to the overall emission because of the low UV/optical flux deep inside the disk. PAHs of 50 carbon atoms are destroyed out to 100 AU in the disk's surface layer, and the resulting spatial extent of the emission does not agree well with observations. Rather, PAHs of about 100 carbon atoms or more are predicted to cause most of the observed emission. The emission is extended on a scale similar to that of the size of the disk. Furthermore, the emission from T Tauri disks is much weaker and concentrated more towards the central star than that from Herbig Ae/Be disks. Positively ionized PAHs are predicted to be largely absent in T Tauri disks because of the weaker radiation field.

R. Visser; V. C. Geers; C. P. Dullemond; J. -C. Augereau; K. M. Pontoppidan; E. F. van Dishoeck

2007-01-22T23:59:59.000Z

137

Persistent DNA damage foci, cellular senescence and low dose radiation  

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

Persistent DNA damage foci, cellular senescence and low dose radiation Persistent DNA damage foci, cellular senescence and low dose radiation Denise Munoz 1 , Albert Davalos 1 , Francis Rodier 1 , Misako Kawahara 1 , Judith Campisi 1,2 and Steven Yannone 1,3 1 Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Mailstop 84-171, Berkeley CA 94720; 2 Buck Institute for Age Research, 8001 Redwood Boulevard, Novato CA 94945; 3 Corresponding author Ionizing radiation (IR) induced DNA double-strand breaks (DSBs) are cytologically detectable as large nuclear foci that contain phosphorylated histone H2AX (γH2AX), the adaptor protein 53BP1, and several other proteins that participate in the sensing and processing of DNA damage (DNA damage foci). In normal human cells, moderately high IR (0.5-1 Gy) doses cause the rapid appearance of these foci (acute DNA damage foci), which gradually disappear

138

Hydrogen peroxide significantly contributes to radiation-induced genomic instability  

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

peroxide significantly contributes to radiation- peroxide significantly contributes to radiation- induced genomic instability Disha Dayal 1 , Sean M. Martin 1 , Sujatha Venkataraman 1 , Charles L. Limoli 2 , Douglas R Spitz 1 . 1 Free Radical and Radiation Biology Program, The University of Iowa, Iowa City, IA- 52246, 2 Department of Radiation Oncology, The University of California, Irvine, CA-92697 Chronic metabolic oxidative stress is associated with genomic instability following exposure to ionizing radiation (IR). Mitochondria have long been known to be a major source of reactive oxygen species (ROS) capable of causing oxidative stress. We hypothesized that radiation damages mitochondria, leading to oxidative stress and eventually genomic instability. This hypothesis is based on preliminary studies in parental

139

THE RADIATION CHEMISTRY OP AMINO ACIDS, PEPTIDES AND PROTEINS IN RELATION TO THE RADIATION STERILIZATION OF HIGH-PROTEIN FOODS  

E-Print Network (OSTI)

to Various Ionizing Radiations. Radiat. Res. , 22, 694 (1968). W. M. Garrison, Radiation Induced Reactions of AminoFrozen Aqueous Solutions, in Radiation Chemistry of Aqueous

Garrison, W.M.

2010-01-01T23:59:59.000Z

140

Hf-Ir (Hafnium - Iridium)  

Science Conference Proceedings (OSTI)

Hf-Ir crystallographic data...Hf-Ir crystallographic data Phase Composition, wt% Ir Pearson symbol Space group (βHf) 0 to ~10.5 cI 2 Im m (αHf) 0 to ~1.5 hP 2 P 6 3 / mmc Hf 2 Ir ~28 to 35.0 cF 96 Fd m Hf 5 Ir 3 39.3 hP 16 P 6 3 / mcm HfIr 51.9 to 59 o ** ? HfIr 3 76 to 82 cP 4 Pm m (Ir) ~91 to 100 cF 4 Fm m...

Note: This page contains sample records for the topic "ionizing radiation ir" 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

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

E-Print Network (OSTI)

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

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

142

Low Dose Radiation Research Program: Assessing Biological Function of DNA  

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

Assessing Biological Function of DNA Damage Response Genes Assessing Biological Function of DNA Damage Response Genes Larry H. Thompson Lawrence Livermore National Laboratory Why This Project To understand the relative importance of individual DNA repair and DNA-damage response pathways to the recovery of mammalian cells after exposure to low doses of ionizing radiation (IR). This understanding may lead to better ways of setting limits on human exposure to IR. In spite of the discovery of many mammalian DNA repair genes, our current knowledge of how many of these genes contribute to cellular recovery from IR exposure is quite limited. Project Goals Measure cellular responses at doses in the 5-100 cGy range, which generally cause changes too small to detect in normal, repair-proficient cells Focus on DNA double-strand breaks (DSBs) and DNA oxidative base

143

Synchrotron Radiation Effects  

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

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

144

Inference of Causal Networks from Time-course Transcription Data in Response to a2 Gy Challenge Dose of Ionizing Radiation with or without a 10 cGy Priming Dose  

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

Causal Networks from Time-course Transcription Data in Response to a Causal Networks from Time-course Transcription Data in Response to a 2 Gy Challenge Dose of Ionizing Radiation with or without a 10 cGy Priming Dose Kai Zhang, Ju Han, Torsten Groesser, Priscilla Cooper, and Bahram Parvin Lawrence Berkeley National Laboratory Goal: To elucidate temporal-dependent gene templates, causal networks, and underlying biological processes that can be inferred in response to a 10 cGy priming dose with or without a later higher challenged dose. Background and significance: Mechanistic inference of regulatory network can provide new insights into radiation systems biology. The main challenge continues to be high dimensionality of data, complex network architecture and limited knowledge of biological processes.

145

Molecular Dynamics Model of Ultraviolet Matrix-Assisted Laser Desorption/Ionization Including Ionization Processes  

E-Print Network (OSTI)

Molecular Dynamics Model of Ultraviolet Matrix-Assisted Laser Desorption/Ionization Including A molecular dynamics model of UV-MALDI including ionization processes is presented. In addition/desorption of molecular systems, it includes radiative and nonradiative decay, exciton hopping, two pooling processes

Zhigilei, Leonid V.

146

Introduction and Fundamentals: Course on Advances in Radiation  

E-Print Network (OSTI)

exposure to Ionizing Radiation - is it really necessary?"Sternglass, "Environmental Radiation and Human Health," op.on the Effects of Atomic Radiation Sources and Effects of

Thomas, Ralph H.

2010-01-01T23:59:59.000Z

147

10 CFR 835- Occupational Radiation Protection  

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

The rules in this part establish radiation protection standards, limits, and program requirements for protecting individuals from ionizing radiation resulting from the conduct of DOE activities.

148

Code of Federal Regulations OCCUPATIONAL RADIATION PROTECTION  

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

The rules in this part establish radiation protection standards, limits, and program requirements for protecting individuals from ionizing radiation resulting from the conduct of DOE activities.

149

Radiation Chemistry and Photochemistry of Ionic Liquids  

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

the nuclear fuel cycle. Therefore, an understanding of the interactions of ionizing radiation and photons with ionic liquids is strongly needed. However, the radiation chemistry...

150

Radiators  

SciTech Connect

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

Webster, D. M.

1985-07-30T23:59:59.000Z

151

Space charge dosimeters for extremely low power measurements of radiation in shipping containers  

DOE Patents (OSTI)

Methods and apparatus are described for space charge dosimeters for extremely low power measurements of radiation in shipping containers. A method includes insitu polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out. Another method includes arranging a plurality of ionizing radiation sensors in a spatially dispersed array; determining a relative position of each of the plurality of ionizing radiation sensors to define a volume of interest; collecting ionizing radiation data from at least a subset of the plurality of ionizing radiation sensors; and triggering an alarm condition when a dose level of an ionizing radiation source is calculated to exceed a threshold.

Britton, Jr., Charles L. (Alcoa, TN); Buckner, Mark A. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Bryan, William L. (Knoxville, TN)

2011-05-03T23:59:59.000Z

152

Space charge dosimeters for extremely low power measurements of radiation in shipping containers  

DOE Patents (OSTI)

Methods and apparatus are described for space charge dosimeters for extremely low power measurements of radiation in shipping containers. A method includes in situ polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out. Another method includes arranging a plurality of ionizing radiation sensors in a spatially dispersed array; determining a relative position of each of the plurality of ionizing radiation sensors to define a volume of interest; collecting ionizing radiation data from at least a subset of the plurality of ionizing radiation sensors; and triggering an alarm condition when a dose level of an ionizing radiation source is calculated to exceed a threshold.

Britton, Jr.; Charles L. (Alcoa, TN); Buckner, Mark A. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Bryan, William L. (Knoxville, TN)

2011-04-26T23:59:59.000Z

153

I\r'  

Office of Legacy Management (LM)

r' r' ( g-.] ic' fz .; w .fl ! : L ' ..j : i ?- z -2"" . 2,-3X-~ Aw23-t 11, 1949 J c. s. ?.%omic ?zaru ccm3ission 7-t i-~n,~-;ra-& 3&-p.Cz' ;"ica P. ' 3. 30x 3 Eacsrs 17, lIaw York :. , ::; /. 1 httetii OP J xl-. P, 3. 2gp C+~t~Sil;lsXl t ?~~$Tly~lf .t: GA.3 L?wjpnaJiQn Of p-3&7:2-Liop 9.0";:7~+50 s' , -ir ,.,,3 iashlla+im it i3 our da3irs 20 be rslia-T.73 of _"\L:t&?T --:wzk&ili* of the SC1298 ' _ _ Zj31Wf end i~i3sio~~31.3 rsskeri31ii izxLi.c~~t& S' ;az&;-d -D~YX-C.I o-Ada - 451 g3ac SyT,kd jl-J$; 3.xi.da - 2% p3 I :&at a 1 a azqi?L;3 3 - ' T-44 pi3. 3 ,LS oxid-\ 3aqr1.93 aar9 ~z;cc?33a~jr la 5.x0 st?%zl*hl~iao- ::>a of In'se-3' -J*-y chs=iical r9tag;P,sta d.ili::d fn cm2 sxlgtit3sl -.- -n4A..*

154

Ir I L  

Office of Legacy Management (LM)

LIST OF FIGURES LIST OF FIGURES 1 2 General location of the Granite City Steel Facility' Granite City, Illinois . . . View of the betatron building, looking south . ' ' 3 View o[ the betatron building, looking west . ' ' ' ' ' 11 4 Diagram of the ground floor of the betatron building ' 5 Photo showing the larger of the two betatrons (no. 1, Fig. ) 6 View of transformer storage area inside the betatron building 7 Directly measured radiation levels inside the betatron building, first level 8 Results of directly measured radiation levels taken in the betatron building, second level . Industrial vacuum cleaner having elevated radiation levels and radionuclide concentrations . I-ocations of smears, and indoor dust and debris samples Results of direct radiation measurements and locations

155

NETL: IRS Tax Credit Program  

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

Solicitations & Business Opportunities IRS Tax Credit Program The Department of Energy's National Energy Technology Laboratory (NETL) is collaborating with the Internal Revenue Service (IRS) to evaluate applications for Tax Credits under Section 1307 of the Energy Policy Act of 2005, and the Emergency Economic Stabilization Act of 2008, per instruction in the Treasury and IRS Announcement 2010-56, which can be found at: http://www.irs.gov/irb/2010-39_IRB/ar09.html or http://www.irs.gov/pub/irs-drop/a-10-56.pdf Specifically, NETL will be evaluating and providing certifications of feasibility for advanced coal and gasification projects consistent with energy policy goals (“DOE certification”). To facilitate the review process, NETL has established this website to receive and respond to questions from prospective applicants regarding the Notices. NETL will post responses to questions or groups of similar questions.

156

Multiscale non-adiabatic dynamics with radiative decay, case study on the post-ionization fragmentation of rare-gas tetramers  

E-Print Network (OSTI)

In this supplementary material, we recollect, for reader's convenience, the general scheme of suggested multiscale model (Sec. 1), and basic informations about approaches used for pilot study: a detailed description of the interaction model (Sec. 2) and dynamical methods used for the dark dynamics step (Sec. 3) reported previously in two preceding studies [1, 2]. In addition, a detailed description of the treatment of radiative processes is also given (Sec. 4).

Jane?ek, Ivan; Naar, Pavel; Renard, Frederic; Kalus, Ren; Gada, Florent X

2012-01-01T23:59:59.000Z

157

Electron Emission From Slightly Oxidized Delta-stabilized Plutonium Generated by its Radioactivity, and Radiation Induced Ionization and Dissociation of Hydrogen at its Surface  

DOE Green Energy (OSTI)

Energy dependent electron emission between zero and 1.4 keV generated by the natural reactivity of plutonium was measured by an electrostatic spectrometer with known acceptance angle and acceptance area. The electron spectral intensity decreases continuously except for a distinctive feature of unknown origin at approximately 180eV. The spectrum was converted to energy dependent electron flux (e/cm{sup 2} s) using the assumption that the emission has a cosine angular distribution. The energy dependent electron mean free path in gases and literature cross sections for electron induced reactions were used to determine the number of ionization and dissociation reactions per cm{sup 2} second, found to be about 8*10{sup 8}/cm{sup 2}s and 1.5*10{sup 8}/cm{sup 2}s, respectively, for hydrogen. These results are to be used with caution until complementary measurements can be made, e.g. independent measurement of the total emitted electron current, since the results here are based on the assumption that the electron emission has a cosine angular distribution. That is unlikely to be correct.

Siekhaus, W J; Nelson, A J

2011-10-26T23:59:59.000Z

158

Hepatitis C virus NS3/4A protein interacts with ATM, impairs DNA repair and enhances sensitivity to ionizing radiation  

Science Conference Proceedings (OSTI)

Hepatitis C virus (HCV) infection is frequently associated with the development of hepatocellular carcinomas and non-Hodgkin's B-cell lymphomas. Nonstructural protein 3 (NS3) of HCV possesses serine protease, nucleoside triphosphatase, and helicase activities, while NS4A functions as a cofactor for the NS3 serine protease. Here, we show that HCV NS3/4A interacts with the ATM (ataxia-telangiectasia mutated), a cellular protein essential for cellular response to irradiation. The expression of NS3/4A caused cytoplasmic translocation of either endogenous or exogenous ATM and delayed dephosphorylation of the phosphorylated ATM and {gamma}-H2AX following ionizing irradiation. As a result, the irradiation-induced {gamma}-H2AX foci persisted longer in the NS3/4A-expressing cells. Furthermore, these cells showed increased comet tail moment in single-cell electrophoresis assay, indicating increased double-strand DNA breaks. The cells harboring an HCV replicon also exhibited cytoplasmic localization of ATM and increased sensitivity to irradiation. These results demonstrate that NS3/4A impairs the efficiency of DNA repair by interacting with ATM and renders the cells more sensitive to DNA damage. This effect may contribute to HCV oncogenesis.

Lai, Chao-Kuen; Jeng, King-Song [Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan (China); Machida, Keigo [Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, 2001 Zonal Avenue, Los Angeles, CA 90033 (United States); Cheng, Yi-Sheng [Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan (China); Lai, Michael M.C. [Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan (China); Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, 2001 Zonal Avenue, Los Angeles, CA 90033 (United States)], E-mail: michlai@gate.sinica.edu.tw

2008-01-20T23:59:59.000Z

159

Low Dose Radiation Response Curves, Networks and Pathways in Human Lymphoblastoid Cells Exposed from 1 to 10 cGy of Acute Gamma Radiation  

E-Print Network (OSTI)

R.B. Mikkelsen, Ionizing radiation-induced, mitochondria-W.K. Rorrer, P.B. Chen, Radiation-induced proliferation ofresponse genes to ionizing radiation in human lymphoblastoid

Wyrobek, A. J.

2011-01-01T23:59:59.000Z

160

Temperature Profile of IR Blocking Windows Used in Cryogenic X-Ray Spectrometers  

SciTech Connect

Cryogenic high-resolution X-ray spectrometers are typically operated with thin IR blocking windows to reduce radiative heating of the detector while allowing good x-ray transmission. We have estimated the temperature profile of these IR blocking windows under typical operating conditions. We show that the temperature in the center of the window is raised due to radiation from the higher temperature stages. This can increase the infrared photon flux onto the detector, thereby increasing the IR noise and decreasing the cryostat hold time. The increased window temperature constrains the maximum window size and the number of windows required. We discuss the consequences for IR blocking window design.

Friedrich, S.; Funk, T.; Drury, O.; Labov, S.E.

2000-08-08T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

Risk of Low Dose/Low Dose Rate Ionizing Radiation to Humans Symposium at the EMS 2009 Annual Meeting - September 2006  

Science Conference Proceedings (OSTI)

The low dose symposium thoughtfully addressed controversy of risk from low dose radiation exposure, hormesis and radon therapy. The stem cell symposium cogently considered the role of DNA damage and repair in hematopoietic stem cells underlying aging and malignancy and provocatively presented evidence that stem cells may have distinct morphologies and replicative properties, as well as special roles in cancer initiation. In the epigenetics symposium, studies illustrated the long range interaction of epigenetic mechanisms, the roles of CTCF and BORIS in region/specific regulation of epigenetic processes, the impact of DNA damage on epigenetic processes as well as links between epigenetic mechanisms and early nutrition and bystander effects.

Morgan, William F.; von Borstel, Robert C.; Brenner,; Redpath, J. Leslie; Erickson, Barbra E.; Brooks,

2009-11-12T23:59:59.000Z

162

Poly [1,1'-bis(ethynyl)-4,4'-biphenyl(bis-tributylphosphine)Pt(II)] solutions used as low dose ionizing radiation dosimeter  

Science Conference Proceedings (OSTI)

In this work, the effect of gamma radiation on the optical properties of polymetallayne poly[1,1'-bis(ethynyl)-4,4'-biphenyl(bis-tributylphosphine)Pt(II)] (Pt-DEBP) in chloroform solution is studied. The samples were irradiated at room temperature with doses from 0.01 Gy to 1 Gy using a {sup 60}Co gamma ray source. A new band at 420 nm is observed in the emission spectra, in superposition to the emission maximum at 398 nm, linearly dependent on dose. We propose to use the ratio of the emission amplitude bands as the dosimetric parameter. This method proved to be robust, accurate, and can be used as a dosimeter in medical applications.

Bronze-Uhle, E. S.; Graeff, C. F. O. [Department of Physics, FC-UNESP, Av. Eng. Luiz Edmundo Carrijo Coube 14-01, 17033-360 Bauru (Brazil)] [Department of Physics, FC-UNESP, Av. Eng. Luiz Edmundo Carrijo Coube 14-01, 17033-360 Bauru (Brazil); Batagin-Neto, A.; Fernandes, D. M. [UNESP-Univ Estadual Paulista, POSMAT-Programa de Pos-Graduacao em Ciencia e Tecnologia de Materiais, Bauru, Sao Paulo (Brazil)] [UNESP-Univ Estadual Paulista, POSMAT-Programa de Pos-Graduacao em Ciencia e Tecnologia de Materiais, Bauru, Sao Paulo (Brazil); Fratoddi, I.; Russo, M. V. [Department of Chemistry, University of Rome 'Sapienza,' P.le A. Moro 5, 00185 Rome (Italy)] [Department of Chemistry, University of Rome 'Sapienza,' P.le A. Moro 5, 00185 Rome (Italy)

2013-06-17T23:59:59.000Z

163

Route to direct multiphoton multiple ionization  

Science Conference Proceedings (OSTI)

We address the concept of direct multiphoton multiple ionization in atoms exposed to intense, short-wavelength radiation and explore the conditions under which such processes dominate over the sequential. Their contribution is shown to be quite robust, even under intensity fluctuations and interaction volume integration, and reasonable agreement with experimental data is also found.

Lambropoulos, P. [Institute of Electronic Structure and Laser, FORTH, P.O. Box 1527, GR-71110 Heraklion (Greece); Department of Physics, University of Crete, P.O. Box 2208, GR-71003 Heraklion, Crete (Greece); Kavli Institute for Theoretical Physics, Santa Barbara, California 93106 (United States); Nikolopoulos, G. M. [Institute of Electronic Structure and Laser, FORTH, P.O. Box 1527, GR-71110 Heraklion (Greece); Kavli Institute for Theoretical Physics, Santa Barbara, California 93106 (United States); Papamihail, K. G. [Department of Physics, University of Crete, P.O. Box 2208, GR-71003 Heraklion, Crete (Greece)

2011-02-15T23:59:59.000Z

164

Low Dose Radiation Research Program: Mary Helen Barcellos-Hoff - 2003  

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

DOE Low Dose Radiation Program Workshop IV DOE Low Dose Radiation Program Workshop IV Abstract Title: TGF-β Protects Human Mammary Epithelial Cells from Radiation-Induced Centrosome Amplification Authors: Mary Helen Barcellos-Hoff, Bahram Parvin, Anna C. Erickson and Rishi Gupta Institutions: Department of Cell and Molecular Biology, Life Sciences Division, Ernest Orlando Lawrence, Berkeley National Laboratory, Berkeley, California In recent studies we have shown that ionizing radiation (IR), a known carcinogen of human and murine mammary gland, compromises human mammary epithelial cell (HMEC) polarity and multicellular organization in a manner characteristic of neoplastic progression through a heritable, non-mutational mechanism (1). Thus, when all cells are irradiated with a significant dose (2 Gy), the daughters of irradiated cells lose their

165

Ionization in Atmospheres of Brown Dwarfs and Extrasolar Planets V: Alfv\\'{e}n Ionization  

E-Print Network (OSTI)

Observations of continuous radio and sporadic X-ray emission from low-mass objects suggest they harbour localized plasmas in their atmospheric environments. For low-mass objects, the degree of thermal ionization is insufficient to qualify the ionized component as a plasma, posing the question: what ionization processes can efficiently produce the required plasma that is the source of the radiation? We propose Alfv\\'{e}n ionization as a mechanism for producing localized pockets of ionized gas in the atmosphere, having sufficient degrees of ionization ($\\geq10^{-7}$) that they constitute plasmas. We outline the criteria required for Alfv\\'{e}n ionization and demonstrate it's applicability in the atmospheres of low-mass objects such as giant gas planets, brown dwarfs and M-dwarfs for both solar and sub-solar metallicities. We find that Alfv\\'{e}n ionization is most efficient at mid to low atmospheric pressures where a seed plasma is easier to magnetize and the pressure gradients needed to drive the required neut...

Stark, Craig R; Diver, Declan A; Rimmer, Paul B

2013-01-01T23:59:59.000Z

166

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

Science Conference Proceedings (OSTI)

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

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

1991-08-01T23:59:59.000Z

167

Code of Federal Regulations PART 835-OCCUPATIONAL RADIATION PROTECTION  

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

General. The rules in this part establish radiation protection standards, limits, and program requirements for protecting individuals from ionizing radiation resulting from the conduct of DOE activities.

168

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

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

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

169

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

170

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

171

Gamma radiation field intensity meter  

SciTech Connect

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

172

Gamma radiation field intensity meter  

SciTech Connect

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

173

A Two-Dimensional Radiation-Turbulence Climate Model. I: Sensitivity to Cirrus Radiative Properties  

Science Conference Proceedings (OSTI)

Based on the thermodynamic energy balance between radiation and vertical plus horizontal dynamic transports, a two-dimensional radiation-turbulence climate model is developed. This model consists of a broadband solar and IR radiation transfer ...

Szu-Cheng S. Ou; Kuo-Nan Liou

1984-08-01T23:59:59.000Z

174

Publication Number: NIST Interagency Report (IR) 7298 ...  

Science Conference Proceedings (OSTI)

... Publication Date: 05/31/2013 Final Publication: http://nvlpubs.nist.gov/nistpubs/ ir/2013/NIST.IR.7298r2.pdf Related Information on CSRC: ...

2013-06-13T23:59:59.000Z

175

Spatially Resolved Observations of the Galactic Center Source, IRS 21  

E-Print Network (OSTI)

We present diffraction-limited 2-25 micron images obtained with the W. M. Keck 10-m telescopes that spatially resolve the cool source, IRS 21, one of a small group of enigmatic objects in the central parsec of our Galaxy that have eluded classification. Modeled as a Gaussian, the azimuthally-averaged intensity profile of IRS 21 has a half-width half-maximum (HWHM) size of 650+/-80 AU at 2.2 microns and an average HWHM size of 1600+/-200 AU at mid-infrared wavelengths. These large apparent sizes imply an extended distribution of dust. The mid-infrared color map indicates that IRS 21 is a self-luminous source rather than an externally heated dust clump as originally suggested. The spectral energy distribution has distinct near- and mid-infrared components. A simple radiative transfer code, which simultaneously fits the near- and mid- infrared photometry and intensity profiles, supports a model in which the near-infrared radiation is scattered and extincted light from an embedded central source, while the mid-infrared emission is from thermally re-radiating silicate dust. We argue that IRS 21 (and by analogy the other luminous sources along the Northern Arm) is a massive star experiencing rapid mass loss and plowing through the Northern Arm, thereby generating a bow shock, which is spatially resolved in our observations.

A. Tanner; A. M. Ghez; M. Morris; E. E. Becklin; A. Cotera; M. Ressler; M. Werner; P. Wizinowich

2002-04-22T23:59:59.000Z

176

Low Dose Radiation Research Program: Cooperation Between Homologous  

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

Cooperation Between Homologous Recombination and the Fanconi Anemia Cooperation Between Homologous Recombination and the Fanconi Anemia Cancer Suppressor Proteins in Minimizing Spontaneous and Radiation-Induced Chromosomal Instability Authors: Larry H. Thompson, John M. Hinz, Robert S. Tebbs, and N. Alice Yamada Institutions: Biosciences Directorate, Lawrence Livermore National Laboratory, Livermore, California Purpose and experimental approach. This study addresses the genetic basis of spontaneous mutagenesis as a means of understanding the DNA damage-response pathways that maintain chromosome stability. It is our view that knowledge of these processes is fundamental to understanding how low dose ionizing radiation (IR) produces chromosomal rearrangements that lead to carcinogenesis. Endogenous oxidative DNA damage is presumed to be a

177

Plasmadynamics and ionization kinetics of thermionic energy conversion  

DOE Green Energy (OSTI)

To reduce the plasma arc-drop, thermionic energy conversion is studied with both analytical and numerical tools. Simplifications are made in both the plasmadynamic and ionization-recombination theories. These are applied to a scheme proposed presently using laser irradiation to enhance the ionization kinetics of the thermionic plasma and thereby reduce the arc-drop. It is also predicted that it is possible to generate the required laser light from a thermionic-type cesium plasma. The analysis takes advantage of theoretical simplifications derived for the ionization-recombination kinetics. It is shown that large laser ionization enhancements can occur and that collisional cesium recombination lasing is expected. To complement the kinetic theory, a numerical method is developed to solve the thermionic plasma dynamics. To combine the analysis of ionization-recombination kinetics with the plasma dynamics of thermionic conversion, a finite difference computer program is constructed. It is capable of solving for both unsteady and steady thermionic converter behavior including possible laser ionization enhancement or atomic recombination lasing. A proposal to improve thermionic converter performance using laser radiation is considered. In this proposed scheme, laser radiation impinging on a thermionic plasma enhances the ionization process thereby raising the plasma density and reducing the plasma arc-drop. A source for such radiation may possibly be a cesium recombination laser operating in a different thermionic converter. The possibility of this being an energy efficient process is discussed. (WHK)

Lawless, J.L. Jr.; Lam, S.H.

1982-02-01T23:59:59.000Z

178

New Facility Focuses on Improved Radiation Standards  

Science Conference Proceedings (OSTI)

... The MIRF contains a high-energy electron beam ... used in ionizing radiation treatments for cancer ... such as polymer curing and wastewater treatment. ...

179

Low Dose Radiation Program: Principal Program Contacts  

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

to the Office of Biological and Environmental Research. Dr. Barcellos-Hoff's current research interests are studies of breast cancer and ionizing radiation. The goal of her...

180

Radiation Sources and Radioactive Materials (Connecticut)  

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

These regulations apply to persons who receive, transfer, possess, manufacture, use, store, handle, transport or dispose of radioactive materials and/or sources of ionizing radiation. Some...

Note: This page contains sample records for the topic "ionizing radiation ir" 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

Low Dose Radiation Research Program: Alec Moreley  

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

Alec Moreley Technical Abstracts 1999 Workshop: Development of PCR-Based Methods for the Detection of Mutagenic Effects of Ionizing Radiation Morley, A., Turner, D., and Sykes, P....

182

Characterization of the role of Fhit in maintenance of genomic integrity following low dose radiation, in vivo and in vitro  

Science Conference Proceedings (OSTI)

The major goal of this study is to determine the effects of the Fhit pathway on low dose ({le} 0.1 Gy) ionizing radiation (IR)-induced genetic instability. Reduction of Fhit protein expression is observed in most solid tumors particularly in those tumors resulting from exposure to environmental carcinogens. Therefore, characterization of the role of the Fhit-dependent pathway in preventing low dose IR-induced genetic instability will provide useful parameters for evaluating the low dose IR-induced risk of mutagenesis and carcinogenesis. We pursued 3 specific aims to study our hypothesis that the Fhit-dependent pathways maintain genomic integrity through adjusting checkpoint response and repair genes expression following low dose IR. Aim 1: Determine whether Fhit interaction with RPA is necessary for Fhit to affect the cellular response to low dose IR. We combined the approaches of in vitro (GST pull-down and site-directed mutagenesis) and in vivo (observing the co-localization and immunoprecipitation of Fhit and RPA in Fhit knock out mouse cells transfected with mutant Fhit which has lost ability to interact with RPA in vitro). Aim 2: Determine the role of genes whose expression is affected by Fhit in low dose irradiated cells. We analyzed the distinct signature of gene expression in low dose irradiated Fhit-/- cells compared with Fhit+/+ cells by combining microarray, gene transfection and siRNA approaches. Aim 3: Determine the role of Fhit in genetic susceptibility to low dose IR in vivo. We compared the gene mutation frequency and the fragile site stability in the cells isolated from the Fhit+/+ and Fhit-/- mice at 1.5 years following low dose IR. These results determine the role of the Fhit-dependent pathway in maintaining genomic integrity in vitro and in vivo, which provide a basis for choosing surrogate markers in the Fhit-dependent pathway to evaluate low dose IR-induced risk of mutagenesis and carcinogenesis.

Ya Wang

2010-05-31T23:59:59.000Z

183

Ionization Energy Search  

Science Conference Proceedings (OSTI)

... SI calorie-based; Select the desired type(s) of ... search for species based on ionization energy values in ... Rules for data types (step 4) (Back to search). ...

2013-07-15T23:59:59.000Z

184

NIST Ionizing Radiation Division 1993 - Technical Highlights  

Science Conference Proceedings (OSTI)

... The high dose rates and tight spacing preclude the use of traditional ionometric ... the polarized 3 He, and partial fabrication of a gas-handling system ...

185

Ionizing Radiation Division - 1997 Technical Highlights  

Science Conference Proceedings (OSTI)

... This PEFC experiment was performed in collaboration with Dr. Richard Bellows of Exxon Research and Engineering. A ...

186

NIST Ionizing Radiation Division 1998 - Future Directions  

Science Conference Proceedings (OSTI)

... sediments, human tissues, and ocean sediment, and is working on additional unique matrices: ashed bone, ocean shellfish, and Rocky Flats Soil-II. ...

187

NIST Ionizing Radiation Division 1998 - Technical Highlights  

Science Conference Proceedings (OSTI)

... of the leaching protocol are being evaluated for selective dissolution of ... SRM 4962F will be used extensively worldwide for ground-water hydrology. ...

188

NIST Ionizing Radiation Division 2000 - Technical Highlights  

Science Conference Proceedings (OSTI)

... the deuteron charge structure in atomic physics ... image lithium ion conduction in batteries have shown ... the effectiveness of future battery technologies ...

189

10.2. Protection from ionizing radiation  

Science Conference Proceedings (OSTI)

exposure will be X-ray generators and radioisotopes used in the manufacture of specimens for ... (vi) during operation the dose equivalent at any accessible surface outside the ... source in the event of the loss of electrical power. 10.2.2.2.

190

NIST Ionizing Radiation Division 1998 - Technical Highlights  

Science Conference Proceedings (OSTI)

... Some potential, technical difficulties by some of the participating laboratories include: 1) data transcription; 2) sample tracking; 3) estimation of limits ...

191

NIST Ionizing Radiation Division 1999 - Technical Highlights  

Science Conference Proceedings (OSTI)

... Institute of Metal Physics, Russia) with 29 ... researchers in polarized gas magnetic resonance ... of Low-Level Radioactivity Natural Matrix Standard ...

192

NIST Ionizing Radiation Division 1994 - Technical Highlights  

Science Conference Proceedings (OSTI)

... and quantifying radioactivity in the natural matrix standards ... counted in the NIST internal gas counting system ... fast-flux reactor in Russia has indicated ...

193

NIST Ionizing Radiation Division 2001 - Technical Highlights  

Science Conference Proceedings (OSTI)

... nuclear weapon plant near the Techa River, Urals, Russia. ... exchange, for producing the polarized 3 He gas. ... level of 240 Pu and natural U into urine ...

194

NIST Ionizing Radiation Division 1995 - Technical Highlights  

Science Conference Proceedings (OSTI)

... system so this low-density gas can be ... the speciation of radionuclides in natural matrix standard ... flux nuclear reactor in Obinsk, Russia and purified ...

195

Fundamentals of Radiation Dosimetry  

Science Conference Proceedings (OSTI)

The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

Bos, Adrie J. J. [Delft University of Technology, Faculty of Applied Sciences, Mekelweg 15, 2629JB Delft (Netherlands)

2011-05-05T23:59:59.000Z

196

and IR-4 Project Programs  

E-Print Network (OSTI)

In both tables, erroneous industry direct effects were reported that do not impact the overall findings of this report. The direct effect numbers previously reported in Tables 4 and 5 were not used in the calculations of overall impacts. The corrected tables in this document do reflect the estimates, as described in the text of the original report. October 22, 2012Executive Summary The Interregional Research Project Number 4 (IR-4 Project) has been a pivotal resource in providing U.S. residents a plentiful and low-cost array of vegetables, fruits, berries and tree nuts since 1963 by facilitating the registration of newer, lower-toxic pest control products with the EPA for application on specialty crops. Specialty crop growers often are at a disadvantage relative to program crop growers in having access to effective crop loss mitigation options against common agricultural pests. Specialty crops make up about 40 percent of the total value of U.S. crop production and include both food and ornamental crops that afford insufficient economic incentive for a pesticide companies to support initial or continuing registration of commercial pesticides. As all agricultural uses of pesticides are regulated by the EPA, each use must be registered or exempted before applied. Such registration is costly, making only registration for uses on any but large acreage crops unprofitable for pesticide companies. The IR-4 Project leverages resources to pursue registration for such uses. Along with supporting the use of reduced-toxicity pesticides, with its Biological and Organic Support program, the IR-4 Project is able to direct necessary resources to meet the U.S. goal of substantially decreasing the environmental and health impacts of agricultural pesticide use following the passage of the Food Quality Protection Act of 1996. This report assesses the economic impact of the IR-4 Project on the U.S. economy. The assessment assumes a long-run presence of the IR-4 Project, such that relevant decision makers recognize and

Steven R. Miller; Andrea Leschewski

2011-01-01T23:59:59.000Z

197

Multidimensional high harmonic spectroscopy: A semi-classical perspective on measuring multielectron rearrangement upon ionization  

E-Print Network (OSTI)

High harmonic spectroscopy has the potential to combine attosecond temporal with sub-Angstrom spatial resolution of the early nuclear and multielectron dynamics in molecules. It involves strong field ionization of the molecule by the IR laser field followed by time-delayed recombination of the removed electron with the molecular ion. The time-delay is controlled on the attosecond time scale by the oscillation of the IR field and is mapped into the harmonic number, providing a movie of molecular dynamics between ionization and recombination. One of the challenges in the analysis of high harmonic signal stems from the fact that the complex dynamics of both ionization and recombination with their multiple observables are entangled in the harmonic signal. Disentangling this information requires multidimensional approach, capable of mapping ionization and recombination dynamics into different independent parameters. We suggest multidimensional high harmonic spectroscopy as a tool for characterizing of ionization and recombination processes separately allowing for simultaneous detection of both the ionization delays and sub-cycle ionization rates. Our method extends the capability of the two dimensional (2D) set-up suggested recently by Shafir et al on reconstructing ionization delays, while keeping the reconstruction procedure as simple as in the original proposal. The scheme is based on the optimization of the high harmonic signal in orthogonally polarized strong fundamental and relatively weak multicolour control fields.

Valeria Serbinenko; Olga Smirnova

2013-05-12T23:59:59.000Z

198

TAT-Mediated Delivery of Tousled Protein to Salivary Glands Protects Against Radiation-Induced Hypofunction  

Science Conference Proceedings (OSTI)

Purpose: Patients treated with radiotherapy for head-and-neck cancer invariably suffer its deleterious side effect, xerostomia. Salivary hypofunction ensuing from the irreversible destruction of glands is the most common and debilitating oral complication affecting patients undergoing regional radiotherapy. Given that the current management of xerostomia is palliative and ineffective, efforts are now directed toward preventive measures to preserve gland function. The human homolog of Tousled protein, TLK1B, facilitates chromatin remodeling at DNA repair sites and improves cell survival against ionizing radiation (IR). Therefore, we wanted to determine whether a direct transfer of TLK1B protein to rat salivary glands could protect against IR-induced salivary hypofunction. Methods: The cell-permeable TAT-TLK1B fusion protein was generated. Rat acinar cell line and rat salivary glands were pretreated with TAT peptide or TAT-TLK1B before IR. The acinar cell survival in vitro and salivary function in vivo were assessed after radiation. Results: We demonstrated that rat acinar cells transduced with TAT-TLK1B were more resistant to radiation (D{sub 0} = 4.13 {+-} 1.0 Gy; {alpha}/{beta} = 0 Gy) compared with cells transduced with the TAT peptide (D{sub 0} = 4.91 {+-} 1.0 Gy; {alpha}/{beta} = 20.2 Gy). Correspondingly, retroductal instillation of TAT-TLK1B in rat submandibular glands better preserved salivary flow after IR (89%) compared with animals pretreated with Opti-MEM or TAT peptide (31% and 39%, respectively; p < 0.01). Conclusions: The results demonstrate that a direct transfer of TLK1B protein to the salivary glands effectively attenuates radiation-mediated gland dysfunction. Prophylactic TLK1B-protein therapy could benefit patients undergoing radiotherapy for head-and-neck cancer.

Sunavala-Dossabhoy, Gulshan, E-mail: gsunav@lsuhsc.edu [Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA (United States)] [Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Palaniyandi, Senthilnathan; Richardson, Charles; De Benedetti, Arrigo [Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA (United States)] [Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Schrott, Lisa [Department of Pharmacology, Toxicology, and Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA (United States)] [Department of Pharmacology, Toxicology, and Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Caldito, Gloria [Department of Bioinformatics and Computational Biology, Louisiana State University Health Sciences Center, Shreveport, LA (United States)] [Department of Bioinformatics and Computational Biology, Louisiana State University Health Sciences Center, Shreveport, LA (United States)

2012-09-01T23:59:59.000Z

199

Cross sections for short pulse single and double ionization ofhelium  

SciTech Connect

In a previous publication, procedures were proposed for unambiguously extracting amplitudes for single and double ionization from a time-dependent wavepacket by effectively propagating for an infinite time following a radiation pulse. Here we demonstrate the accuracy and utility of those methods for describing two-photon single and one-photon double ionization of helium. In particular it is shown how narrow features corresponding to autoionizing states are easily resolved with these methods.

Palacios, Alicia; Rescigno, Thomas N.; McCurdy, C. William

2007-11-27T23:59:59.000Z

200

Fotovoltinio modulio su koncentratoriumi projektavimas ir tyrimas.  

E-Print Network (OSTI)

??Baigiamajame magistro darbe suprojektuotos ir pagamintos dviej? r?i? viesos koncentratorin?s sistemos: jungtin? parabolin? ir sistema su Frenelio l?iu. Atlikta saul?s element? efektyvumo analiz?, inagrin?tos vies? (more)

Gaili?nas,; Paulius

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
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201

Publication Number: NIST Interagency Report (IR) 7298 ...  

Science Conference Proceedings (OSTI)

... Title: Glossary of Key Information Security Terms ... Interagency Report (IR) 7298, Revision 2, Glossary of Key Information Security Terms. ...

2013-06-13T23:59:59.000Z

202

Parameterization of Outgoing Infrared Radiation Derived from Detailed Radiative Calculations  

Science Conference Proceedings (OSTI)

State-of-the-art radiative transfer models can calculate outgoing infrared (IR) irradiance at the top of the atmosphere (F) to an accuracy suitable for climate modeling given the proper atmospheric profiles of temperature and absorbing gases and ...

Starley L. Thompson; Stephen G. Warren

1982-12-01T23:59:59.000Z

203

Characterization of Thallium Bromide (TlBr) for Room Temperature Radiation Detectors  

E-Print Network (OSTI)

1.1 Motivation: Radiation Detection for HomelandSecurity . . . . . . . . . . 1.2 Semiconductor Radiationand related features of radiation ionization energies in

Smith, Holland McTyeire

2013-01-01T23:59:59.000Z

204

Code of Federal Regulations PART 835-OCCUPATIONAL RADIATION PROTECTION Subpart A- General Provisions  

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

The rules in this part establish radiation protection standards, limits, and program requirements for protecting individuals from ionizing radiation resulting from the conduct of DOE activities.

205

Radiation effects on humans  

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

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

206

Low Dose Radiation Research Program: Ionizing Radiation-induced...  

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

p53-directed, DNA damage response pathway. The p53 protein, activated indirectly by the ATM protein kinase, transactivates target genes and thus induces cell cycle progression...

207

Carbon nanotube IR detectors (SV)  

SciTech Connect

Sandia National Laboratories (Sandia) and Lockheed Martin Corporation (LMC) collaborated to (1) evaluate the potential of carbon nanotubes as channels in infrared (IR) photodetectors; (2) assemble and characterize carbon nanotube electronic devices and measure the photocurrent generated when exposed to infrared light;(3) compare the performance of the carbon nanotube devices with that of traditional devices; and (4) develop and numerically implement models of electronic transport and opto-electronic behavior of carbon nanotube infrared detectors. This work established a new paradigm for photodetectors.

Leonard, F. L.

2012-03-01T23:59:59.000Z

208

Low Dose Radiation Induced DNA Damage Signaling and Repair Responses in  

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

Induced DNA Damage Signaling and Repair Responses in Induced DNA Damage Signaling and Repair Responses in Human 3-Dimensional Skin Model System Yanrong Su, Jarah Meador and Adayabalam S. Balajee Center for Radiological Research, College of Physicians and Surgeons, Columbia University, 630 West, 168th Street, New York, NY 10032. Exposure to ionizing radiation (IR) inflicts a wide variety of lesions in the genomic DNA. Among them, DNA double strand break (DSB) is considered to be the critical lesion for most of the deleterious radiation effects including carcinogenesis. Much of our knowledge on induction and repair kinetics of DSB has come from studies in two dimensional cell culture systems. However, the damage signaling and repair responses to DSB in tissue microenvironment are largely unknown. Knowledge of tissue responses to

209

Relationship Between Chromatin Structure and Sensitivity to Molecularly Targeted Auger Electron Radiation Therapy  

Science Conference Proceedings (OSTI)

Purpose: The open structure of euchromatin renders it susceptible to DNA damage by ionizing radiation (IR) compared with compact heterochromatin. The effect of chromatin configuration on the efficacy of Auger electron radiotherapy was investigated. Methods and Materials: Chromatin structure was altered in MDA-MB-468 and 231-H2N human breast cancer cells by suberoylanilide hydroxamic acid (SAHA), 5-aza-2-deoxycytidine, or hypertonic treatment. The extent and duration of chromatin structural changes were evaluated using the micrococcal nuclease assay. DNA damage ({gamma}H2AX assay) and clonogenic survival were evaluated after exposure to {sup 111}In-DTPA-hEGF, an Auger electron-emitting radiopharmaceutical, or IR. The intracellular distribution of {sup 111}In-DTPA-hEGF after chromatin modification was investigated in cell fractionation experiments. Results: Chromatin remained condensed for up to 20 minutes after NaCl and in a relaxed state 24 hours after SAHA treatment. The number of {gamma}H2AX foci per cell was greater in MDA-MB-468 and 231-H2N cells after IR (0.5 Gy) plus SAHA (1 {mu}M) compared with IR alone (16 {+-} 0.6 and 14 {+-} 0.3 vs. 12 {+-} 0.4 and 11 {+-} 0.2, respectively). More {gamma}H2AX foci were observed in MDA-MB-468 and 231-H2N cells exposed to {sup 111}In-DTPA-hEGF (6 MBq/{mu}g) plus SAHA vs. {sup 111}In-DTPA-hEGF alone (11 {+-} 0.3 and 12 {+-} 0.7 vs. 9 {+-} 0.4 and 7 {+-} 0.3, respectively). 5-aza-2-deoxycytidine enhanced the DNA damage caused by IR and {sup 111}In-DTPA-hEGF. Clonogenic survival was reduced in MDA-MB-468 and 231-H2N cells after IR (6 Gy) plus SAHA (1 {mu}M) vs. IR alone (0.6% {+-} 0.01 and 0.3% {+-} 0.2 vs. 5.8% {+-} 0.2 and 2% {+-} 0.1, respectively) and after {sup 111}In-DTPA-hEGF plus SAHA compared to {sup 111}In-DTPA-hEGF alone (21% {+-} 0.4% and 19% {+-} 4.6 vs. 33% {+-} 2.3 and 32% {+-} 3.7). SAHA did not affect {sup 111}In-DTPA-hEGF nuclear localization. Hypertonic treatment resulted in fewer {gamma}H2AX foci per cell after IR and {sup 111}In-DTPA-hEGF compared to controls but did not significantly alter clonogenic survival. Conclusions: Chromatin structure affects DNA damage and cell survival after exposure to Auger electron radiation.

Terry, Samantha Y.A. [CR-UK/MRC Gray Institute for Radiation Oncology and Biology, Department of Oncology, University of Oxford, Oxford (United Kingdom); Vallis, Katherine A., E-mail: katherine.vallis@oncology.ox.ac.uk [CR-UK/MRC Gray Institute for Radiation Oncology and Biology, Department of Oncology, University of Oxford, Oxford (United Kingdom)

2012-07-15T23:59:59.000Z

210

Vasculatures in Tumors Growing From Preirradiated Tissues: Formed by Vasculogenesis and Resistant to Radiation and Antiangiogenic Therapy  

SciTech Connect

Purpose: To investigate vasculatures and microenvironment in tumors growing from preirradiated tissues (pre-IR tumors) and study the vascular responses of pre-IR tumors to radiation and antiangiogenic therapy. Methods and Materials: Transgenic adenocarcinoma of the mouse prostate C1 tumors were implanted into unirradiated or preirradiated tissues and examined for vascularity, hypoxia, and tumor-associated macrophage (TAM) infiltrates by immunohistochemistry. The origin of tumor endothelial cells was studied by green fluorescent protein-tagged bone marrow (GFP-BM) transplantation. The response of tumor endothelial cells to radiation and antiangiogenic agent was evaluated by apoptotic assay. Results: The pre-IR tumors had obvious tumor bed effects (TBE), with slower growth rate, lower microvascular density (MVD), and more necrotic and hypoxic fraction compared with control tumors. The vessels were dilated, tightly adhered with pericytes, and incorporated with transplanted GFP-BM cells. In addition, hypoxic regions became aggregated with TAM. As pre-IR tumors developed, the TBE was overcome at the tumor edge where the MVD increased, TAM did not aggregate, and the GFP-BM cells did not incorporate into the vessels. The vessels at tumor edge were more sensitive to the following ionizing radiation and antiangiogenic agent than those in the central low MVD regions. Conclusions: This study demonstrates that vasculatures in regions with TBE are mainly formed by vasculogenesis and resistant to radiation and antiangiogenic therapy. Tumor bed effects could be overcome at the edge of larger tumors, but where vasculatures are formed by angiogenesis and sensitive to both treatments. Vasculatures formed by vasculogenesis should be the crucial target for the treatment of recurrent tumors after radiotherapy.

Chen, Fang-Hsin; Chiang, Chi-Shiun [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Taiwan (China); Wang, Chun-Chieh [Department of Radiation Oncology, Chang Gung Memorial Hospital-LinKou, Taiwan (China); Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taiwan (China); Fu, Sheng-Yung [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Taiwan (China); Tsai, Chien-Sheng [Department of Radiation Oncology, Chang Gung Memorial Hospital-LinKou, Taiwan (China); Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taiwan (China); Jung, Shih-Ming [Department of Pathology, Chang Gung Memorial Hospital-LinKou, Taiwan (China); Wen, Chih-Jen [Animal Molecular Imaging Center, Chang Gung Memorial Hospital-LinKou, Taiwan (China); Lee, Chung-Chi [Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taiwan (China); Hong, Ji-Hong, E-mail: jihong@adm.cgmh.org.tw [Department of Radiation Oncology, Chang Gung Memorial Hospital-LinKou, Taiwan (China); Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taiwan (China)

2011-08-01T23:59:59.000Z

211

Ir L (I.~ DEPARTMENT OF ENERGY ALBUQUERQUE OPERATIONS OFFICE  

Office of Legacy Management (LM)

Ir Ir L (I.~ DEPARTMENT OF ENERGY ALBUQUERQUE OPERATIONS OFFICE I.: ~ CONTRACT NO. DE-AC04-83AL18796 1. Vicinity Property i: Completion Report i , . Remedial Actions , cContractor 4,. -~'~ ~for the Uranium Mill Tailings ~~~z ~ Remedial Actions Project - MK-FEROUSON COMPANY *C~Ad PEE *CMIWN>tfIOW VICINITY PROPERTY COMPLETION REPORT AT CA-401 MAYERS STREET BRIDGEVILLE, PA 15017 JUNE 30, 1987 FOR URANIUM MILL TAILINGS REMEDIAL ACTION PROJECT OFFICE ALBUQUERQUE OPERATIONS OFFICE U.S. DEPARTMENT OF ENERGY ALBUQUERQUE, NM BY MK-FERGUSON CC IPANY AND CHEM-NUCLEAR SYSTEMS, INC. MK-Ferguson Company has been granted authorization to perform remedial action under the Uranium Mill Tailings Radiation Control Act of 1978, Public Law 95-604. Remedial action was done in accordance to the EPA Standards for

212

Semiconductor radiation detector  

DOE Patents (OSTI)

A semiconductor detector for ionizing electromagnetic radiation, neutrons, and energetic charged particles. The detecting element is comprised of a compound having the composition I-III-VI.sub.2 or II-IV-V.sub.2 where the "I" component is from column 1A or 1B of the periodic table, the "II" component is from column 2B, the "III" component is from column 3A, the "IV" component is from column 4A, the "V" component is from column 5A, and the "VI" component is from column 6A. The detecting element detects ionizing radiation by generating a signal proportional to the energy deposited in the element, and detects neutrons by virtue of the ionizing radiation emitted by one or more of the constituent materials subsequent to capture. The detector may contain more than one neutron-sensitive component.

Bell, Zane W. (Oak Ridge, TN); Burger, Arnold (Knoxville, TN)

2010-03-30T23:59:59.000Z

213

Monte Carlo Photoionization Simulations of Diffuse Ionized Gas  

E-Print Network (OSTI)

We demonstrate that the observed increase of some nebular line ratios with height above the midplane in the diffuse ionized gas (DIG) in the Milky Way and other galaxies is a natural consequence of the progressive hardening of the radiation field far from the midplane ionizing sources. To obtain increasing temperatures and line ratios away from the midplane, our photoionization simulations of a multi-component interstellar medium do not require as much additional heating (over and above that from photoionization) as previous studies that employed one dimensional, spherically averaged models. Radiation leaking into the DIG from density bounded H II regions is generally harder in the H-ionizing continuum and has its He-ionizing photons suppressed compared to the ionizing source of the H II region. In line with other recent investigations, we find that such leaky H II region models can provide elevated temperatures and line ratios, and a lower He+ fraction in the DIG. For a composite model representing the relative spectral types of O stars in the solar neighbourhood, we find that additional heating less than 1.0E-26 n_e ergs/s/cm^3 can reproduce the observed elevated line ratios in the DIG. This additional heating is considerably less than previous estimates due to the natural hardening of the radiation field reaching large heights in our simulations.

Kenneth Wood; John S. Mathis

2004-02-17T23:59:59.000Z

214

Scintillator Waveguide For Sensing Radiation  

DOE Patents (OSTI)

The present invention is an apparatus for detecting ionizing radiation, having: a waveguide having a first end and a second end, the waveguide formed of a scintillator material wherein the therapeutic ionizing radiation isotropically generates scintillation light signals within the waveguide. This apparatus provides a measure of radiation dose. The apparatus may be modified to permit making a measure of location of radiation dose. Specifically, the scintillation material is segmented into a plurality of segments; and a connecting cable for each of the plurality of segments is used for conducting scintillation signals to a scintillation detector.

Bliss, Mary (West Richland, WA); Craig, Richard A. (West Richland, WA); Reeder; Paul L. (Richland, WA)

2003-04-22T23:59:59.000Z

215

Rayleigh-Taylor Instability at Ionization Fronts: Perturbation Analysis  

E-Print Network (OSTI)

The linear growth rate of the Rayleigh-Taylor instability (RTI) at ionization fronts is investigated via perturbation analysis in the limit of incompressible fluids. In agreement with previous numerical studies is found that absorption of ionizing radiation inside the HII region due to hydrogen recombinations suppresses the growth of instabilities. In the limit of a large density contrast at the ionization front the RTI growth rate has the simple analytical solution n=-nur+(nur^2+gk)^(1/2), where nur is the hydrogen recombination rate inside the HII region, k is the perturbation's wavenumber and g is the effective acceleration in the frame of reference of the front. Therefore, the growth of surface perturbations with wavelengths lambda >> lambda_{cr} = 2\\pi g/nur^2 is suppressed by a factor (lambda_{cr}/4lambda)^(1/2) with respect to the non-radiative incompressible RTI. Implications on stellar and black hole feedback are briefly discussed.

Ricotti, Massimo

2013-01-01T23:59:59.000Z

216

IRS Actions on Decisions | Data.gov  

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

digital@treasury.gov Unique Identifier TREAS-4430 Public Access Level public Data Dictionary http:www.irs.govapppicklistlistactionsOnDecisions.html Data Download URL...

217

IRS Internal Revenue Bulletin | Data.gov  

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

digital@treasury.gov Unique Identifier TREAS-4431 Public Access Level public Data Dictionary http:www.irs.govapppicklistlistinternalRevenueBulletins.html Data Download URL...

218

Low Dose Radiation Program: Radiation Biology and the Radiation Research  

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

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

219

Low Dose Radiation Research Program: Proteomic and Biochemical...  

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

proteomic changes including protein expression levels and post-translational modification due to low dose-rate ionizing radiation Expected Outcomes Increased differentiation...

220

Low Dose Radiation Research Program: 2011 Current Projects  

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

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

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


221

Low Dose Radiation Research Program: Depletion of the Vertebrate...  

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

Laboratory, Berkeley, California To better understand the responses to low dose ionizing radiation, we proposed in Aim 1 of our Low Dose grant to use dominant-negative...

222

The Effects of Ionizing Irradiation  

Science Conference Proceedings (OSTI)

Page 1. The Effects of Ionizing Irradiation on Liquid, Dried, and Absorbed DNA Extracts ... Page 12. Study Shipped Land Carrier Irradiation ? ...

2012-02-29T23:59:59.000Z

223

Living with radiation  

SciTech Connect

The authors present an account of the hopes and fears associated with ionizing radiation, extending from nuclear energy and medical radiation to nuclear weapons. They argue that a justified fear of nuclear weapons has led to a widespread, unjustified, and unreasoning fear of the beneficial applications of radiation. Although these two aspects of atomic energy are tied together-they both involve the nucleus of the atom and its radioactive rays-a deep misunderstanding of this relationship by the general public has evolved since the time of the atomic bombing of Hiroshima and Nagasaki. The authors' aim is to place the beneficial applications of nuclear radiation in perspective.

Wagner, H.N. Jr. (Johns Hopkins Medical Institutions, Baltimore, MD (USA). Div. of Nuclear Medicine); Ketchum, L.E. (Proclinica, Inc., New York, NY (US))

1989-01-01T23:59:59.000Z

224

Monte Carlo Photoionization Simulations of Diffuse Ionized Gas  

E-Print Network (OSTI)

We demonstrate that the observed increase of some nebular line ratios with height above the midplane in the diffuse ionized gas (DIG) in the Milky Way and other galaxies is a natural consequence of the progressive hardening of the radiation field far from the midplane ionizing sources. To obtain increasing temperatures and line ratios away from the midplane, our photoionization simulations of a multi-component interstellar medium do not require as much additional heating (over and above that from photoionization) as previous studies that employed one dimensional, spherically averaged models. Radiation leaking into the DIG from density bounded H II regions is generally harder in the H-ionizing continuum and has its He-ionizing photons suppressed compared to the ionizing source of the H II region. In line with other recent investigations, we find that such leaky H II region models can provide elevated temperatures and line ratios, and a lower He+ fraction in the DIG. For a composite model representing the relat...

Wood, K; Wood, Kenneth; Mathis, John S.

2004-01-01T23:59:59.000Z

225

Improved ARM-SGP TOA OLR Fluxes from GOES-8 IR Radiances Based on CERES Data  

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

ARM-SGP TOA OLR Fluxes from GOES-8 IR ARM-SGP TOA OLR Fluxes from GOES-8 IR Radiances Based on CERES Data D. R. Doelling and M. M. Khaiyer Analytical Services and Materials, Inc. Hampton, Virginia P. Minnis National Aeronautics and Space Administration Langley Research Center Hampton, Virginia Introduction The radiation budget at the top of the atmosphere (TOA) is a quantity of fundamental importance to the Atmospheric Radiation Measurement (ARM) Program. Thus, it is necessary to measure the radiation budget components, broadband shortwave albedo and outgoing longwave radiation (OLR), as accurately as possible. Measurement of OLR over the ARM surface sites has only been possible since the advent of Clouds and the Earth's Radiant Energy System (CERES; Wielicki et al. 1998) in 1998. Prior to

226

An Improved Daylight Correction for IR Loss in ARM Diffuse SW Measurements  

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

An Improved Daylight Correction for IR Loss An Improved Daylight Correction for IR Loss in ARM Diffuse SW Measurements C. N. Long, K. Younkin, and K. L. Gaustad Pacific Northwest National Laboratory Richland, Washington J. A. Augustine National Oceanic and Atmospheric Administration Air Resources Laboratory Surface Radiation Research Branch Boulder, Colorado Introduction A paper by Cess et al. (2000) notes that some clear-sky diffuse shortwave (SW) measurements they were using from the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site exhibited less than Rayleigh magnitude. Remarking that this is a physical impossibility, the obvious conclusion forwarded by the authors was that there was some problem with the ARM SGP diffuse SW data. Shortly thereafter, the problem of infrared (IR) loss from thermopile-based single black detector

227

Low Dose Radiation Program: Links - Organizations Conducting Radiation  

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

Conducting Low Dose Radiation Research Conducting Low Dose Radiation Research DOE Low Dose Radiation Research Program DoReMi Integrating Low Dose Research High Level Expert Group (HLEG) on European Low Dose Risk Research Multidisciplinary European Low Dose Initiative (MELODI) RISC-RAD Radiosensitivity of Individuals and Susceptibility to Cancer induced by Ionizing Radiation United States Transuranium & Uranium Registries Organizations Conducting other Radiation Research Argonne National Laboratory (ANL) Armed Forces Radiology Research Institute (AFRRI) Atmospheric Radiation Measurement (ARM) Program Brookhaven National Laboratory (BNL) Center for Devices and Radiological Health (CDRH) Central Research Institute of Electric Power Industry (CRIEPI) Colorado State University Columbia University

228

Partially Ionized Atmospheres of Neutron Stars with Strong Magnetic Fields  

DOE Green Energy (OSTI)

We construct hydrogen atmosphere models for strongly magnetized neutron stars in thermodynamic equilibrium, taking into account partial ionization. The presence of bound states affects the equation of state, absorption coefficients, and polarizability tensor of a strongly magnetized plasma. Therefore the partial ionization influences the polarization vectors and opacities of normal electromagnetic waves, and thus the spectra of outgoing radiation. Here we review a model suitable for the most typical neutron-star atmospheres and focus on the problems that remain to be solved for its extension to other atmospheric parameters.

Potekhin, A.

2005-01-28T23:59:59.000Z

229

Third-harmonic generation and multiphoton ionization spectroscopy  

SciTech Connect

Nonlinear phenomena, such as multiphoton excitation (MPE) processes leading to ionization and third-harmonic generation (THG) in gases have become the issue of extensive studies over recent years. Studies in rare gases in particular have resulted in several interesting observations in this respect. Thus, it has been established that three-photon resonantly enhanced multiphoton ionization (MPI) in the vicinity of states which are single photon optically coupled to the ground state may occur in efficient competition with THG. The present work demonstrates several new effects which may appear when third-harmonic radiation is present during MPI.

Fotakis, C.; Stockdale, J.A.D.; Proctor, M.J.

1987-01-01T23:59:59.000Z

230

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

Science Conference Proceedings (OSTI)

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

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

1995-06-01T23:59:59.000Z

231

Deinococcus geothermalis: The Pool of Extreme Radiation Resistance Genes Shrinks  

SciTech Connect

Bacteria of the genus Deinococcus are extremely resistant to ionizing radiation (IR), ultraviolet light (UV) and desiccation. The mesophile Deinococcus radiodurans was the first member of this group whose genome was completely sequenced. Analysis of the genome sequence of D. radiodurans, however, failed to identify unique DNA repair systems. To further delineate the genes underlying the resistance phenotypes, we report the whole-genome sequence of a second Deinococcus species, the thermophile Deinococcus geothermalis, which at itsoptimal growth temperature is as resistant to IR, UV and desiccation as D. radiodurans, and a comparative analysis of the two Deinococcus genomes. Many D. radiodurans genes previously implicated in resistance, but for which no sensitive phenotype was observed upon disruption, are absent in D. geothermalis. In contrast, most D. radiodurans genes whose mutants displayed a radiation-sensitive phenotype in D. radiodurans are conserved in D. geothermalis. Supporting the existence of a Deinococcus radiation response regulon, a common palindromic DNA motif was identified in a conserved set of genes associated with resistance, and a dedicated transcriptional regulator was predicted. We present the case that these two species evolved essentially the same diverse set of gene families, and that the extreme stress-resistance phenotypes of the Deinococcus lineage emerged progressively by amassing cell-cleaning systems from different sources, but not by acquisition of novel DNA repair systems. Our reconstruction of the genomic evolution of the Deinococcus-Thermus phylum indicates that the corresponding set of enzymes proliferated mainly in the common ancestor of Deinococcus. Results of the comparative analysis weaken the arguments for a role of higher-order chromosome alignment structures in resistance; more clearly define and substantially revise downward the number of uncharacterized genes that might participate in DNA repair and contribute to resistance; and strengthen the case for a role in survival of systems involved in manganese and iron homeostasis.

Makarova, Kira S.; Omelchenko, Marina V.; Gaidamakova, Elena K.; Matrosova, Vera Y.; Vasilenko, Alexander; Zhai, Min; Lapidus, Alla; Copeland, Alex; Kim, Edwin; Land, Miriam; Mavrommatis, Konstantinos; Pitluck, Samuel; Richardson, Paul M.; Detter, Chris; Brettin, Thomas; Saunders, Elizabeth; Lai, Barry; Ravel, Bruce; Kemner, Kenneth M.; Wolf, Yuri I.; Sorokin, Alexander; Gerasimova, Anna V.; Gelfand, Mikhail S.; Fredrickson, James K.; Koonin, Eugene V.; Daly, Michael J.

2007-07-24T23:59:59.000Z

232

Broadly tunable picosecond ir source  

DOE Patents (OSTI)

A picosecond traveling-wave parametric device capable of controlled spectral bandwidth and wavelength in the infrared is reported. Intense 1.064 ..mu..m picosecond pulses (1) pass through a 4.5 cm long LiNbO/sub 3/ optical parametric oscillator crystal (2) set at its degeneracy angle. A broad band emerges, and a simple grating (3) and mirror (4) arrangement is used to inject a selected narrow-band into a 2 cm long LiNbO/sub 3/ optical parametric amplifier crystal (5) along a second pump line. Typical input energies at 1.064 ..mu..m along both pump lines are 6 to 8 mJ for the oscillator and 10 mJ for the amplifier. This yields 1 mJ of tunable output in the range 1.98 to 2.38 ..mu..m which when down-converted in a 1 cm long CdSe crystal mixer (6) gives 2 ..mu..J of tunable radiation over the 14.8 to 18.5 ..mu..m region. The bandwidth and wavelength of both the 2 and 16 ..mu..m radiation output are controlled solely by the diffraction grating.

Campillo, A.J.; Hyer, R.C.; Shapiro, S.L.

1980-04-23T23:59:59.000Z

233

Broadly tunable picosecond IR source  

DOE Patents (OSTI)

A picosecond traveling-wave parametric device capable of controlled spectral bandwidth and wavelength in the infrared is reported. Intense 1.064 .mu.m picosecond pulses (1) pass through a 4.5 cm long LiNbO.sub.3 optical parametric oscillator crystal (2) set at its degeneracy angle. A broad band emerges, and a simple grating (3) and mirror (4) arrangement is used to inject a selected narrow-band into a 2 cm long LiNbO.sub.3 optical parametric amplifier crystal (5) along a second pump line. Typical input energies at 1.064 .mu.m along both pump lines are 6-8 mJ for the oscillator and 10 mJ for the amplifier. This yields 1 mJ of tunable output in the range 1.98 to 2.38 .mu.m which when down-converted in a 1 cm long CdSe crystal mixer (6) gives 2 .mu.J of tunable radiation over the 14.8 to 18.5 .mu.m region. The bandwidth and wavelength of both the 2 and 16 .mu.m radiation output are controlled solely by the diffraction grating.

Campillo, Anthony J. (Nesconset, NY); Hyer, Ronald C. (Los Alamos, NM); Shapiro, Stanley J. (Los Alamos, NM)

1982-01-01T23:59:59.000Z

234

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

E-Print Network (OSTI)

to low levels of ionizing radiation: BEIR VII Phase 2. TheBlake G, Genant HK (1999) Radiation exposure in bone mineralGuglielmi Thomas M. Link Radiation exposure in X-ray-based

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

2010-01-01T23:59:59.000Z

235

Comparisons of Clear-Sky Outgoing Far-IR Flux Inferred from Satellite Observations and Computed from the Three Most Recent Reanalysis Products  

Science Conference Proceedings (OSTI)

The far-IR spectrum plays an important role in the earths radiation budget and remote sensing. The authors compare the near-global (80S80N) outgoing clear-sky far-IR flux inferred from the collocated Atmospheric Infrared Sounder (AIRS) and ...

Xiuhong Chen; Xianglei Huang; Norman G. Loeb; Heli Wei

2013-01-01T23:59:59.000Z

236

IRS General Counsel Memoranda | Data.gov  

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

digital@treasury.gov Unique Identifier TREAS-4432 Public Access Level public Data Dictionary http:www.irs.govfoiaarticle0,,id103756,00.html Data Download URL http:...

237

High pressure xenon ionization detector  

DOE Patents (OSTI)

A method is provided for detecting ionization comprising allowing particles that cause ionization to contact high pressure xenon maintained at or near its critical point and measuring the amount of ionization. An apparatus is provided for detecting ionization, the apparatus comprising a vessel containing a ionizable medium, the vessel having an inlet to allow high pressure ionizable medium to enter the vessel, a means to permit particles that cause ionization of the medium to enter the vessel, an anode, a cathode, a grid and a plurality of annular field shaping rings, the field shaping rings being electrically isolated from one another, the anode, cathode, grid and field shaping rings being electrically isolated from one another in order to form an electric field between the cathode and the anode, the electric field originating at the anode and terminating at the cathode, the grid being disposed between the cathode and the anode, the field shaping rings being disposed between the cathode and the grid, the improvement comprising the medium being xenon and the vessel being maintained at a pressure of 50 to 70 atmospheres and a temperature of 0.degree. to 30.degree. C.

Markey, John K. (New Haven, CT)

1989-01-01T23:59:59.000Z

238

High pressure xenon ionization detector  

DOE Patents (OSTI)

A method is provided for detecting ionization comprising allowing particles that cause ionization to contact high pressure xenon maintained at or near its critical point and measuring the amount of ionization. An apparatus is provided for detecting ionization, the apparatus comprising a vessel containing a ionizable medium, the vessel having an inlet to allow high pressure ionizable medium to enter the vessel, a means to permit particles that cause ionization of the medium to enter the vessel, an anode, a cathode, a grid and a plurality of annular field shaping rings, the field shaping rings being electrically isolated from one another, the anode, cathode, grid and field shaping rings being electrically isolated from one another in order to form an electric field between the cathode and the anode, the electric field originating at the anode and terminating at the cathode, the grid being disposed between the cathode and the anode, the field shaping rings being disposed between the cathode and the grid, the improvement comprising the medium being xenon and the vessel being maintained at a pressure of 50 to 70 atmospheres and a temperature of 0 to 30 C. 2 figs.

Markey, J.K.

1989-11-14T23:59:59.000Z

239

Novel target configurations for selective ionization state studies in molybdenum  

Science Conference Proceedings (OSTI)

Details of experiments aimed at achieving low ionization state selectivity in molybdenum are presented. Targets are excited with a 10 J CO{sub 2} laser and the resultant VUV spectrum (300--700 {Angstrom}) has been studied. Combinations of focal spot size, target depth, and target geometries are compared. Simple attenuation of energy is shown not to vary ionization stage composition significantly. Experiments conducted with grazing incidence targets result only in a hot plasma. Modular targets with cooling cylinders of various radii demonstrated good selectivity of the ionization states, but with low absolute signals. Finally, results from combinations of focal spot adjustment and radiative cooling illustrate increased control over desired plasma temperature and density for spectroscopic studies of molybdenum. 7 refs., 14 figs.

Ilcisin, K.J.; Feldman, U.; Schwob, J.L.; Wouters, A. (Princeton Univ., NJ (USA). Plasma Physics Lab.); Suckewer, S. (Princeton Univ., NJ (USA). Plasma Physics Lab. Princeton Univ., NJ (USA). Dept. of Mechanical and Aerospace Engineering)

1990-03-01T23:59:59.000Z

240

IR Spectral Bands and Performance | Open Energy Information  

Open Energy Info (EERE)

2013 DOI Not Provided Check for DOI availability: http:crossref.org Online Internet link for IR Spectral Bands and Performance Citation Chris Douglass. IR Spectral Bands...

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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

Ionization of hydrogen and ionized helium by slow antiprotons  

E-Print Network (OSTI)

We study the ionization process involving antiproton and hydrogen in the energy range between 0.1 keV to 500 keV, using single center close coupling approximation. We construct the scattering wave function using B-spline bases. The results obtained for ionization of atomic hydrogen are compared with other existing theoretical calculations as well as with the available experimental data. The present results are found to be encouraging. We also employed this method to study the ionization of ionized helium in the energy range between 1 and 500 keV. On comparision, the present results are found to interpret well the cross section values calculated using other theories.

Sahoo, S; Walters, H R J

2004-01-01T23:59:59.000Z

242

Pulsed helium ionization detection system  

DOE Patents (OSTI)

A helium ionization detection system is provided which produces stable operation of a conventional helium ionization detector while providing improved sensitivity and linearity. Stability is improved by applying pulsed dc supply voltage across the ionization detector, thereby modifying the sampling of the detectors output current. A unique pulse generator is used to supply pulsed dc to the detector which has variable width and interval adjust features that allows up to 500 V to be applied in pulse widths ranging from about 150 nsec to about dc conditions.

Ramsey, R.S.; Todd, R.A.

1985-04-09T23:59:59.000Z

243

Optical ionization detector  

DOE Patents (OSTI)

An optical ionization detector wherein a beam of light is split so that one arm passes through a fiber optics and the other arm passes through a gas-filled region, and uses interferometry to detect density changes in a gas when charged particles pass through it. The gas-filled region of the detector is subjected to a high electric field and as a charged particle traverses this gas region electrons are freed from the cathode and accelerated so as to generate an electron avalanche which is collected on the anode. The gas density is effected by the electron avalanche formation and if the index or refraction is proportional to the gas density the index will change accordingly. The detector uses this index change by modulating the one arm of the split light beam passing through the gas, with respect to the other arm that is passed through the fiber optic. Upon recombining of the beams, interference fringe changes as a function of the index change indicates the passage of charged particles through the gaseous medium.

Wuest, Craig R. (Danville, CA); Lowry, Mark E. (Castro Valley, CA)

1994-01-01T23:59:59.000Z

244

Optical ionization detector  

DOE Patents (OSTI)

An optical ionization detector wherein a beam of light is split so that one arm passes through a fiber optics and the other arm passes through a gas-filled region, and uses interferometry to detect density changes in a gas when charged particles pass through it. The gas-filled region of the detector is subjected to a high electric field and as a charged particle traverses this gas region electrons are freed from the cathode and accelerated so as to generate an electron avalanche which is collected on the anode. The gas density is effected by the electron avalanche formation and if the index or refraction is proportional to the gas density the index will change accordingly. The detector uses this index change by modulating the one arm of the split light beam passing through the gas, with respect to the other arm that is passed through the fiber optic. Upon recombining of the beams, interference fringe changes as a function of the index change indicates the passage of charged particles through the gaseous medium. 3 figures.

Wuest, C.R.; Lowry, M.E.

1994-03-29T23:59:59.000Z

245

AN EXPERIMENTAL EVALUATION OF THE RADIATION PROTECTION AFFORDED BY A LARGE MODERN CONCRETE OFFICE BUILDING  

SciTech Connect

An experimental study was made to determine the effective shielding provided by a modern reinforced-concrete office building (AEC Headquarters building) from nuclear fall-out. Pocket ionization chambers were used for measurement of the radiation-field strength. Fall-out was simulated with distributed and point-source configurations of Co/sup 60/ and Ir/sup 192/ sources. Four typical sections were selected for study, and experiments were performed on each. These included an external wing with exposed basement walls and an external wing with a buried basement. Roof studies were made on an internal wing with a full basement and on the east end of wing A, which has a thin-roof construction. The thick-roof construction of 8 in. of concrete and 2 in. of rigid insulation covers all the building except the east end of wing A, which has 4 in. of concrete and 2 in. of insulation. (auth)

Batter, J.F. Jr.; Kaplan, A.L.; Clarke, E.T.

1959-05-01T23:59:59.000Z

246

Mechanin?s aktyvacijos ir pried? poveikis ekstrakcinio pushidra?io fosfogipso ir jo gamini? savyb?ms.  

E-Print Network (OSTI)

??Fosfogipso perdirbimas tampa vis aktualesn? problema ne tik Lietuvoje, bet ir visame pasaulyje. Tiek Lietuvos, tiek ir pasaulio mokslininkai jau seniai bando spr?sti fosfogipso perdirbimo (more)

Gaidu?is, Sergejus

2010-01-01T23:59:59.000Z

247

Low Dose Radiation Research Program: Molecular Characterization...  

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

the Role of SOD Genes in Mammalian Cellular Response to Low Dose Ionizing Radiation Chaun-Yuan Li Duke University Medical Center Durham, NC Why this Project? To evaluate the roles...

248

METHOD FOR MEASURING RADIATION  

DOE Patents (OSTI)

A method for measuring an unknown integrated quantity of radiation with a condenser ionization chamber is described. The chamber is initially charged to a predetermined voltage by a voltage source. The chamber is then removed from the source and exposed to an unknown quantity of radiation for a period of time. The quantity of radiation to which the chamber was exposed is then measured by detecting the magnitude of the pulse of current necessary to recharge the chamber of its initial value through a suitable impedance. The current pulse is amplified and measured directly by a suitable pulse height analyzing system. (AEC)

Roesch, W.C.; McCall, R.C.

1961-11-21T23:59:59.000Z

249

Field ionization from carbon nanofibers  

E-Print Network (OSTI)

The Micro Gas Analyzer project aims to develop power-efficient, high resolution, high sensitivity, portable and real-time gas sensors. We developed a field ionizer array based on gated CNTs. Arrays of CNTs are used because ...

Adeoti, Bosun J

2008-01-01T23:59:59.000Z

250

Humidity effects in ionization chambers  

SciTech Connect

Capacitance variations due to humidity alterations have been suggested as the cause of ionization chamber current variations. The validity of the arguments is seriously questioned on several points. (auth)

Bengtsson, L.G.

1973-01-01T23:59:59.000Z

251

Rayleigh-Taylor Instability of Ionization Front around Black Holes  

E-Print Network (OSTI)

We examine the role of ionizing radiation emitted from black holes (BHs) in suppressing the growth of the Rayleigh-Taylor instability (RTI) across the ionization front (I-front) that forms when the gas fueling the BH is neutral. We use radiation-hydrodynamic simulations to show that the RTI is suppressed for non-accelerating fronts on all scales resolved in our simulations. A necessary condition for the stability of the I-front is that the radius of the Str\\"omgren sphere is larger than the Bondi radius. When this condition is violated the I-front collapses producing an accretion luminosity burst. Transient growth of the RTI occurs only during the accretion burst when the effective acceleration in the frame of reference of the I-front increases significantly due to the rapid expansion of the Str\\"omgren sphere.

Park, KwangHo; Di Matteo, Tiziana; Reynolds, Christopher S

2013-01-01T23:59:59.000Z

252

Amplifier Design for Proportional Ionization Chambers  

SciTech Connect

This paper presents the requirements of a nuclear amplifier of short resolving time, designed to accept pulses of widely varying amplitudes. Data are given which show that a proportional ionization chamber loaded with a 1,000-ohm resistor develops pulses of 0.5 microsecond duration and several volts amplitude. Results indicate that seven basic requirements are imposed on the amplifier when counting soft beta and gamma radiation in the presence of alpha particles, without absorbers. It should, (1) have a fast recovery time, (2) have a relatively good low frequency response, (3) accept pulses of widely varying heights without developing spurious pulsed, (4) have a limiting output stage, (5) preserve the inherently short rise time of the chamber, (6) minimize pulse integration, and (7) have sufficient gain to detect the weak pulses well below the chamber voltage at which continuous discharge takes place. The results obtained with an amplifier which meets these requirements is described. A formula is derived which indicates that redesign of the proportional ionization chamber might eliminate the need for an amplifier. This may be possible if the radioactive particles are collimated parallel to the collecting electrode.

Baker, W. H.

1950-08-24T23:59:59.000Z

253

RADIATION DOSIMETER  

DOE Patents (OSTI)

An improvement was made in the determination of amounts of ionizing radiation, particularly low-energy beta particles of less than 1000 rad total dose by means of fluid-phase dosimeter employing a stabilized-- sensitized ferrous-ferric colorimetric system in a sulphuric acid medium. The improvement in the dosimeter consists of adding to the ferrous-ferric system in concentrations of 10/sub -2/ to 10/sup -4/M an organic compound having one or more carboxylic or equivalent groups, such compounds being capable of chelating or complexing the iron ions in the solution. Suitable sensitizing and stabilizing agents are benzoic, phthalic, salicylic, malonic, lactic, maleic, oxalic, citric, succinic, phenolic tartaric, acetic, and adipic acid, as well as other compounds which are added to the solution alone or in certain combinations. As in conventional fluid-phase dosimeters, the absorbed dosage is correlated with a corresponding change in optical density at particular wavelengths of the solution.

Balkwell, W.R. Jr.; Adams, G.D. Jr.

1960-05-10T23:59:59.000Z

254

Neutron And Gamma Detector Using An Ionization Chamber With An Integrated  

NLE Websites -- All DOE Office Websites (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

255

Three-Dimensional Studies of the Warm Ionized Medium in the Milky Way using WHAM  

E-Print Network (OSTI)

The Wisconsin H-Alpha Mapper (WHAM) is a high throughput Fabry-Perot facility developed specifically to detect and explore the warm, ionized component of the interstellar medium at high spectral resolution. It began operating at Kitt Peak, Arizona in 1997 and has recently completed the WHAM Northern Sky Survey (WHAM-NSS), providing the first global view of the distribution and kinematics of the warm, diffuse H II in the Milky Way. This H-alpha survey reveals a complex spatial and kinematic structure in the warm ionized medium and provides a foundation for studies of the temperature and ionization state of the gas, the spectrum and strength of the ionizing radiation, and its relationship to other components of the interstellar medium and sources of ionization and heating within the Galactic disk and halo. More information about WHAM and the Survey can be found at http://www.astro.wisc.edu/wham/.

R. J. Reynolds; L. M. Haffner; G. J. Madsen

2002-01-23T23:59:59.000Z

256

Three-Dimensional Studies of the Warm Ionized Medium in the Milky Way using WHAM  

E-Print Network (OSTI)

The Wisconsin H-Alpha Mapper (WHAM) is a high throughput Fabry-Perot facility developed specifically to detect and explore the warm, ionized component of the interstellar medium at high spectral resolution. It began operating at Kitt Peak, Arizona in 1997 and has recently completed the WHAM Northern Sky Survey (WHAM-NSS), providing the first global view of the distribution and kinematics of the warm, diffuse H II in the Milky Way. This H-alpha survey reveals a complex spatial and kinematic structure in the warm ionized medium and provides a foundation for studies of the temperature and ionization state of the gas, the spectrum and strength of the ionizing radiation, and its relationship to other components of the interstellar medium and sources of ionization and heating within the Galactic disk and halo. More information about WHAM and the Survey can be found at http://www.astro.wisc.edu/wham/.

Reynolds, R J; Madsen, G J

2002-01-01T23:59:59.000Z

257

Numerical simulation of the pre-ionization processes during nanosecond-pulse discharge in nitrogen  

Science Conference Proceedings (OSTI)

The pre-ionization of nitrogen gas by high-voltage nanosecond pulse discharges is studied using one-dimensional particle-in-cell numerical simulations. The comparison between the various mechanisms of pre-ionization, i.e., by runaway electrons, x-rays, and ultraviolet radiation, is presented. It is shown that runaway electrons produce a much higher number of electron-ion pairs than those generated by x-rays, which accompany the process of runaway electron generation. Also, results of simulations showed that among photo-ionization mechanisms the most significant gas pre-ionization is caused by x-rays generated in the process of impact ionization of the K-shell of nitrogen atoms.

Levko, D.; Gurovich, V. Tz.; Krasik, Ya. E.

2012-01-01T23:59:59.000Z

258

Low Dose Radiation Research Program: Image Gallery  

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

Image Gallery Image Gallery These are images, photographs, and charts presented or developed for Low Dose Radiation Research Investigators’ Meetings. They may be used for presentations or reports. To save, right click on the picture, then choose "Save picture as." U.S. annual per-capita effective radiation dose from various sources for 1980. various sources 1980 Enlarge Image. U.S. annual per-capita effective radiation dose from various sources for 2006. various sources 2006 Enlarge Image. U.S. annual per-capita effective radiation dose from man-made sources in the United States for 2006. man-made 2006 Enlarge Image. Ionizing Radiation Dose Ranges showing the wide range of radiation doses that humans experience (Rem) Enlarge Image. Ionizing Radiation Dose Ranges showing the wide range of radiation doses that humans experience

259

Accounting for Unresolved Clouds in a 1D Infrared Radiative Transfer Model. Part I: Solution for Radiative Transfer, Including Cloud Scattering and Overlap  

Science Conference Proceedings (OSTI)

Various aspects of infrared radiative transfer through clouds are investigated. First, three solutions to the IR radiative transfer equation are presented and assessed, each corresponding to a different approximation for the Planck function. It ...

J. Li

2002-12-01T23:59:59.000Z

260

Epothilone B Confers Radiation Dose Enhancement in DAB2IP Gene Knock-Down Radioresistant Prostate Cancer Cells  

Science Conference Proceedings (OSTI)

Purpose: In metastatic prostate cancer, DOC-2/DAB2 interactive protein (DAB2IP) is often downregulated and has been reported as a possible prognostic marker to predict the risk of aggressive prostate cancer (PCa). Our preliminary results show that DAB2IP-deficient PCa cells are radioresistant. In this study, we investigated the anticancer drug Epothilone B (EpoB) for the modulation of radiosensitivity in DAB2IP-deficient human PCa cells. Methods and Materials: We used a stable DAB2IP-knock down human PCa cell line, PC3 shDAB2IP, treated with EpoB, ionizing radiation (IR), or the combined treatment of EpoB and IR. The modulation of radiosensitivity was determined by surviving fraction, cell cycle distribution, apoptosis, and DNA double-strand break (DSB) repair. For in vivo studies, the PC3shDAB2IP xenograft model was used in athymic nude mice. Results: Treatment with EpoB at IC{sub 50} dose (33.3 nM) increased cellular radiosensitivity in the DAB2IP-deficient cell line with a dose enhancement ratio of 2.36. EpoB delayed the DSB repair kinetics after IR and augmented the induction of apoptosis in irradiated cells after G{sub 2}/M arrest. Combined treatment of EpoB and radiation enhanced tumor growth delay with an enhancement factor of 1.2. Conclusions: We have demonstrated a significant radiation dose enhancement using EpoB in DAB2IP-deficient prostate cancer cells. This radiosensitization can be attributed to delayed DSB repair, prolonged G{sub 2} block, and increased apoptosis in cells entering the cell cycle after G{sub 2}/M arrest.

Kong Zhaolu [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Institute of Radiation Medicine, Fudan University, Shanghai (China); Raghavan, Pavithra [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Xie Daxing [Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Boike, Thomas [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Burma, Sandeep; Chen, David [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Simmons Comprehensive Cancer Center, 2201 Inwood Road, Dallas, TX 75390 (United States); Chakraborty, Arup [College of Pharmacy, University of Southern Nevada, Henderson, NV (United States); Hsieh, Jer-Tsong [Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Simmons Comprehensive Cancer Center, 2201 Inwood Road, Dallas, TX 75390 (United States); Graduate Institute of Cancer Biology, China Medical University, Taichung, Taiwan (China); Saha, Debabrata, E-mail: debabrata.saha@utsouthwestern.ed [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Simmons Comprehensive Cancer Center, 2201 Inwood Road, Dallas, TX 75390 (United States)

2010-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

Low Dose Radiation Research Program: Bruce E. Lehnert  

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

E. Lehnert E. Lehnert Los Alamos National Laboratory Past Project Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated Cells: Pathways Analysis in Support of Risk Assessment. Technical Abstracts 2002 Workshop: Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated cells: Pathways Analysis in Support of Risk Assessment. Lehnert, B.E., Cary, R., Gadbois, D. and Gupta G. 2001 Workshop: Low Dose, Low Dose Rate Effects of Ionizing Radiation in Irradiated and Unirradiated Cells. Lehnert, B.E. 1999 Workshop: Low Dose, Low Dose Rate Effects of Ionizing Radiation in Irradiated and Unirradiated Cells. Lehnert, B.E. Publications Lehnert, B.E., Radiation bystander effects. U.S.Department of Energy Research News (March 6 issue) Goldberg, Z. and Lehnert, B.E. (2002). Radiation-induced effects in

262

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

E-Print Network (OSTI)

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

Howett, Susan

2013-01-01T23:59:59.000Z

263

Low dose diagnostic radiation exposure and cancer risk in Trp53...  

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

University Abstract The cancer risk associated with exposure to low doses of ionizing radiation has traditionally been extrapolated from effects observed at high doses and high...

264

Packet personal radiation monitor  

DOE Patents (OSTI)

A personal radiation monitor of the chirper type is provided for detecting ionizing radiation. A battery powered high voltage power supply is used to generate and apply a high voltage bias to a G-M tube radiation sensor. The high voltage is monitored by a low-loss sensing network which generates a feedback signal to control the high voltage power supply such that the high voltage bias is recharged to +500 VDC when the current pulses of the sensor, generated by the detection of ionizing radiation events, discharges the high voltage bias to +450 VDC. During the high voltage recharge period an audio transducer is activated to produce an audible "chirp". The rate of the "chirps" is controlled by the rate at which the high voltage bias is recharged, which is proportional to the radiation field intensity to which the sensor is exposed. The chirp rate sensitivity is set to be approximately 1.5 (chirps/min/MR/hr.). The G-M tube sensor is used in a current sensing mode so that the device does not paralyze in a high radiation field.

Phelps, James E. (Knoxville, TN)

1989-01-01T23:59:59.000Z

265

Consistency of vendor-specified activity values for {sup 192}Ir brachytherapy sources  

SciTech Connect

A long-term comparison was done between the manufacturer-stated {sup 192}Ir activity and the measured {sup 192}Ir activities determined with a well-type ionization chamber. Sources for a Nucletron Micro Selectron high-dose-rate (HDR) unit were used for this purpose. The radioactive sources reference activities were determined using a PTW well-type ionization chamber traceable to the National Institute of Standards and Technology Primary Calibration Laboratory. The measurements were taken in a period of 56 months with 17 different radioactive sources. The manufacturer stated activities were taken from the source calibration certificate provided by the manufacturer. These values were compared with the measured activities. The results have shown that both the percentage deviation of the monthly control measurements with the well-type chamber and the ratio between the measured activities to the manufacturer-stated value lie within {+-} 2.5%. These results were compared with similar published data and with uncertainty level (3% of the mean and 5% maximum deviation from mean) for brachytherapy sources calibration recommended by the AAPM. It was concluded that a threshold level of {+-}2.5% can be used as a suitable quality assurance indicator to spot problems in our department. The typical {+-}5% uncertainty as provided by the manufacturers may be tightened to {+-}3% to be more in line with published AAPM reports.

Austerlitz, Carlos, E-mail: camposc@ecu.edu [Department of Radiation Oncology, East Carolina University, Greenville, NC (United States); Wolfe, Melodee; Campos, Diana; Sibata, C.H. [Department of Radiation Oncology, East Carolina University, Greenville, NC (United States)

2012-04-01T23:59:59.000Z

266

Life-span effects of ionizing radiation in the beagle dog: A summary account of four decades of research funded by the US Department of Energy and its predecessor agencies  

Science Conference Proceedings (OSTI)

Nearly 40 years ago, the US Atomic Energy Commission made a far- reaching commitment to the support of life-span radiation-effects studies in a relatively long-lived animal, the beagle dog. Something in the range of 200 million dollars has already been spent on a group of closely related experiments, many of which are only now coming to fruition. Responsible fiscal management of these studies, directed toward securing an optimum return from past investments, and toward creative planning of future directions, requires a comprehensive view of this total effort. This report is designed to provide that comprehensive view. This is primarily intended as a research management document. Evaluation and interpretation are tasks for those directly involved in conducting these experiments. The limited objective of the present document is to describe what has been done, to give some of the background for why it was done, to describe results already realized and applications that have been made of these results -- all in a manner designed to display the total effort rather than piecemeal details. While proposing no specific answers to the questions ''Where do we go from here.''it is hoped that the document will provide a basis for approaching that question in an informed manner. The maintenance of a continuity of scientific understanding and direction in these experiments, which often continue beyond the initiating investigators' working life, is no small part of the problem involved in conducting these experiments.

Thompson, R.C.

1989-01-01T23:59:59.000Z

267

About EffectiveŽ Height of the Aerosol Atmosphere in Visible and IR Wavelength Range  

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

"Effective" Height of the Aerosol Atmosphere in "Effective" Height of the Aerosol Atmosphere in Visible and IR Wavelength Range V. N. Uzhegov, D. M. Kabanov, M. V. Panchenko, Yu. A. Pkhalagov, and S. M. Sakerin Institute of Atmospheric Optics Tomsk, Russia Introduction Aerosol component of the atmosphere is one of the important factors affecting the radiation budget of the space - atmosphere - underlying surface system in visible and infrared (IR) wavelength ranges. It is extremely important to take into account the contribution of this component into the extinction of solar radiation under cloudless sky conditions. Sometimes it is important to know not only the total value of the aerosol component of extinction, but also to have the possibility to estimate the "effective" height of

268

Pulse mode readout techniques for use with non-gridded industrial ionization chambers  

SciTech Connect

Highly sensitive readout technique for precision long-term radiation measurements has been developed and tested in the Radiation Control Department at Jefferson Lab. The new electronics design is used to retrieve ionization data in a pulse mode. The dedicated data acquisition system works with M=Audio Audiophile 192 High-Definition 24-bit/192 kHz audio cards, taking data in continuous waveform recording mode. The on-line data processing algorithms extract signals of the ionization events from the data flow and measure the ionization value for each event. Two different ion chambers are evaluated. The first is a Reuter-Stokes Argon-filled (at 25 atm) High Pressure Ionization Chamber (HPIC), commonly used as a detector part in many GE Reuter-Stokes instruments of the RSS series. The second is a VacuTec Model 70181, 5 atm Xenon-filled ionization chamber. Results for both chambers indicate that the techniques allow using industrial ICs for high sensitivity and precision long-term radiation measurements, while at the same time providing information about spectral characteristics of the radiation fields.

Popov, Vladimir E. [JLAB; Degtiarenko, Pavel V. [JLAB

2011-10-01T23:59:59.000Z

269

Enhanced radiation resistant fiber optics  

DOE Patents (OSTI)

A process for producing an optical fiber having enhanced radiation resitance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation.

Lyons, P.B.; Looney, L.D.

1992-12-31T23:59:59.000Z

270

Low Dose Radiation Program: Links - Online Literature  

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

Online Literature Online Literature Journals, Books and other Publications Armed Forces Radiobiology Research Institute Chornobyl Center for Nuclear Safety Radioactive Waste and Radioecology "Insight" Magazine Central Research Institute of the Electric Power Industry (CRIEPI) News: Aiming at an information center on low dose radiation research Health Physics International Journal of Radiation Biology Iranian Journal of Radiation Research Journal of Radiological Protection National Council on Radiation Protection and Measurements Radiation Research U.S. Department of Energy (DOE) Information Bridge Reports Animal Cancer Tests and Human Cancer Risk Assessment: A Broad Perspective Effects of Ionizing Radiation: Atomic Bomb Survivors and Their Children (1945-1995) Health Effects of Exposure to Low Levels of Ionizing Radiation: BEIR

271

Enhanced radiation detectors using luminescent materials  

DOE Patents (OSTI)

A radiation detecting device comprising a radiation sensing element, and a layer of luminescent material to expand the range of wavelengths over which the sensing element can efficiently detect radiation. The luminescent material being selected to absorb radiation at selected wavelengths, causing the luminescent material to luminesce, and the luminescent radiation being detected by the sensing element. Radiation sensing elements include photodiodes (singly and in arrays), CCD arrays, IR detectors and photomultiplier tubes. Luminescent materials include polymers, oligomers, copolymers and porphyrines, Luminescent layers include thin films, thicker layers, and liquid polymers.

Vardeny, Zeev V. (Holladay, UT); Jeglinski, Stefan A. (Durham, NC); Lane, Paul A. (Sheffield, GB)

2001-01-01T23:59:59.000Z

272

Carbon nanotube-based field ionization vacuum  

E-Print Network (OSTI)

We report the development of a novel micropump architecture that uses arrays of isolated vertical carbon nanotubes (CNT) to field ionize gas particles. The ionized gas molecules are accelerated to and implanted into a ...

Jang, Daniel, M. Eng. Massachusetts Institute of Technology

2012-01-01T23:59:59.000Z

273

MUCOOL: Ionization Cooling R&D  

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

Laboratory MUCOOL Muon Ionization Cooling R&D Welcome to the muon ionization cooling experimental R&D page. The MuCool collaboration has been formed to pursue the development of a...

274

Packet personal radiation monitor  

DOE Patents (OSTI)

A personal radiation monitor of the chirper type is provided for detecting ionizing radiation. A battery powered high voltage power supply is used to generate and apply a high voltage bias to a G-M tube radiation sensor. The high voltage is monitored by a low-loss sensing network which generates a feedback signal to control the high voltage power supply such that the high voltage bias is recharged to +500 VDC when the current pulses of the sensor, generated by the detection of ionizing radiatonevents, discharges the high voltage bias to +450 VDC. During the high voltage recharge period an audio transducer is activated to produce an audible ''chirp''. The rate of the ''chirps'' is controlled by the rate at which the high voltage bias is recharged, which is proportional to the radiation field intensity to which the sensor is exposed. The chirp rate sensitivity is set to be approximately 1.5 (chirps/min/MR/hr.). The G-M tube sensor is used in a current sensing mode so that the device does not paralyze in a high radiation field. 2 figs.

Phelps, J.E.

1988-03-31T23:59:59.000Z

275

Amorphous silicon radiation detectors  

DOE Patents (OSTI)

Hydrogenated amorphous silicon radiation detector devices having enhanced signal are disclosed. Specifically provided are transversely oriented electrode layers and layered detector configurations of amorphous silicon, the structure of which allow high electric fields upon application of a bias thereby beneficially resulting in a reduction in noise from contact injection and an increase in signal including avalanche multiplication and gain of the signal produced by incoming high energy radiation. These enhanced radiation sensitive devices can be used as measuring and detection means for visible light, low energy photons and high energy ionizing particles such as electrons, x-rays, alpha particles, beta particles and gamma radiation. Particular utility of the device is disclosed for precision powder crystallography and biological identification.

Street, Robert A. (Palo Alto, CA); Perez-Mendez, Victor (Berkeley, CA); Kaplan, Selig N. (El Cerrito, CA)

1992-01-01T23:59:59.000Z

276

Amorphous silicon radiation detectors  

DOE Patents (OSTI)

Hydrogenated amorphous silicon radiation detector devices having enhanced signal are disclosed. Specifically provided are transversely oriented electrode layers and layered detector configurations of amorphous silicon, the structure of which allow high electric fields upon application of a bias thereby beneficially resulting in a reduction in noise from contact injection and an increase in signal including avalanche multiplication and gain of the signal produced by incoming high energy radiation. These enhanced radiation sensitive devices can be used as measuring and detection means for visible light, low energy photons and high energy ionizing particles such as electrons, x-rays, alpha particles, beta particles and gamma radiation. Particular utility of the device is disclosed for precision powder crystallography and biological identification. 13 figs.

Street, R.A.; Perez-Mendez, V.; Kaplan, S.N.

1992-11-17T23:59:59.000Z

277

Measuring Radiation  

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

Measurement Activity SI Units and Prefixes Conversions Safety Around Radiation Sources Types of Radiation Exposure Managing Radiation Emergencies Procedure Demonstration...

278

Modeling early galaxies using radiation hydrodynamics  

Science Conference Proceedings (OSTI)

This simulation uses a flux-limited diffusion solver to explore the radiation hydrodynamics of early galaxies, in particular, the ionizing radiation created by Population III stars. At the time of this rendering, the simulation has evolved to a redshift ... Keywords: astrophysics, modeling, visualization

Joseph A. Insley; Rick Wagner; Robert Harkness; Daniel R. Reynolds; Michael L. Norman; Mark Hereld; Eric C. Olson; Michael E. Papka; Venkatram Vishwanath

2011-11-01T23:59:59.000Z

279

Broadband Water Vapor Transmission Functions for Atmospheric IR Flux Computations  

Science Conference Proceedings (OSTI)

Transmission functions associated with water vapor molecular line and e-type absorption in the IR spectral regions are presented in the form of simple analytical functions and small tables, from which atmospheric IR fluxes and cooling rates can ...

Ming-Dah Chou

1984-05-01T23:59:59.000Z

280

Study of the response of low pressure ionization chambers  

E-Print Network (OSTI)

The Beam Loss Monitoring System (BLM) of the Large Hadron Collider (LHC) is based on parallel plate Ionization Chambers (IC) with active volume 1.5l and a nitrogen filling gas at 0.1 bar overpressure. At the largest loss locations, the ICs generate signals large enough to saturate the read-out electronics. A reduction of the active volume and filling pressure in the ICs would decrease the amount of charge collected in the electrodes, and so provide a higher saturation limit using the same electronics. This makes Little Ionization Chambers (LIC) with both reduced pressure and small active volume a good candidate for these high radiation areas. In this contribution we present measurements performed with several LIC monitors with reduced active volume and various filling pressures. These detectors were tested under various conditions with different beam setups, with standard LHC ICs used for calibration purposes

Nebot Del Busto, E; Effinger, E; Grishin, V; Herranz Alvarez, J

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

Microwave remote sensing of ionized air.  

SciTech Connect

We present observations of microwave scattering from ambient room air ionized with a negative ion generator. The frequency dependence of the radar cross section of ionized air was measured from 26.5 to 40 GHz (Ka-band) in a bistatic mode with an Agilent PNA-X series (model N5245A) vector network analyzer. A detailed calibration scheme is provided to minimize the effect of the stray background field and system frequency response on the target reflection. The feasibility of detecting the microwave reflection from ionized air portends many potential applications such as remote sensing of atmospheric ionization and remote detection of radioactive ionization of air.

Liao, S.; Gopalsami, N.; Heifetz, A.; Elmer, T.; Fiflis, P.; Koehl, E. R.; Chien, H. T.; Raptis, A. C. (Nuclear Engineering Division)

2011-07-01T23:59:59.000Z

282

Radiative Properties of Cirrus Clouds in the Infrared Region  

Science Conference Proceedings (OSTI)

A multiple-scattering radiative transfer model is employed to evaluate the 11 ?m and the broad-band infrared (IR) fluxes, cooling rates and emittances in model cirrus clouds for a number of standard vertical atmospheric profiles of temperature ...

Graeme L. Stephens

1980-02-01T23:59:59.000Z

283

SURFACE LAYER ACCRETION IN CONVENTIONAL AND TRANSITIONAL DISKS DRIVEN BY FAR-ULTRAVIOLET IONIZATION  

Science Conference Proceedings (OSTI)

Whether protoplanetary disks accrete at observationally significant rates by the magnetorotational instability (MRI) depends on how well ionized they are. Disk surface layers ionized by stellar X-rays are susceptible to charge neutralization by small condensates, ranging from {approx}0.01 {mu}m sized grains to angstrom-sized polycyclic aromatic hydrocarbons (PAHs). Ion densities in X-ray-irradiated surfaces are so low that ambipolar diffusion weakens the MRI. Here we show that ionization by stellar far-ultraviolet (FUV) radiation enables full-blown MRI turbulence in disk surface layers. Far-UV ionization of atomic carbon and sulfur produces a plasma so dense that it is immune to ion recombination on grains and PAHs. The FUV-ionized layer, of thickness 0.01-0.1 g cm{sup -2}, behaves in the ideal magnetohydrodynamic limit and can accrete at observationally significant rates at radii {approx}> 1-10 AU. Surface layer accretion driven by FUV ionization can reproduce the trend of increasing accretion rate with increasing hole size seen in transitional disks. At radii {approx}<1-10 AU, FUV-ionized surface layers cannot sustain the accretion rates generated at larger distance, and unless turbulent mixing of plasma can thicken the MRI-active layer, an additional means of transport is needed. In the case of transitional disks, it could be provided by planets.

Perez-Becker, Daniel [Department of Physics, University of California, Berkeley, CA 94720 (United States); Chiang, Eugene [Departments of Astronomy and Earth and Planetary Science, University of California, Berkeley, CA 94720 (United States)

2011-07-01T23:59:59.000Z

284

STORAGE RING CROSS-SECTION MEASUREMENTS FOR ELECTRON IMPACT SINGLE AND DOUBLE IONIZATION OF Fe{sup 9+} AND SINGLE IONIZATION OF Fe{sup 10+}  

SciTech Connect

We have measured electron impact ionization from the ground state of Fe{sup 9+} and Fe{sup 10+} over the relative electron-ion collision energy ranges 200-1900 eV and 250-1800 eV, respectively. The ions were confined in an ion storage ring long enough for essentially all metastable levels to radiatively relax to the ground state. For single ionization, we find a number of discrepancies between the existing theoretical cross sections and our results. The calculations appear to neglect some excitation-autoionization (EA) channels, particularly from n = 3 to n' excitations, which are important near threshold, and those from n = 2 {yields} 3 excitations, which contribute at about 650 eV. Conversely, at higher energies the calculations appear to overestimate the importance of EA channels due to excitation into levels where n {>=} 4. The resulting experimental rate coefficients agree with the most recent theory for Fe{sup 9+} to within 16% and for Fe{sup 10+} to within 19% at temperatures where these ions are predicted to form in collisional ionization equilibrium. We have also measured double ionization of Fe{sup 9+} forming Fe{sup 11+} in the energy range 450-3000 eV and found that although there is an appreciable cross section for direct double ionization, the dominant mechanism appears to be through direct ionization of an inner shell electron producing an excited state that subsequently stabilizes through autoionization.

Hahn, M.; Novotny, O.; Savin, D. W. [Columbia Astrophysics Laboratory, Columbia University, 550 West 120th Street, New York, NY 10027 (United States); Becker, A.; Grieser, M.; Krantz, C.; Wolf, A. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Lestinsky, M.; Repnow, R. [GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstr. 1, D-64291 Darmstadt (Germany); Mueller, A.; Schippers, S.; Spruck, K. [Institut fuer Atom- und Molekuelphysik, Justus-Liebig-Universitaet Giessen, Leihgesterner Weg 217, D-35392 Giessen (Germany)

2012-11-20T23:59:59.000Z

285

Molecular mechanisms and cellular consequences of low-dose exposure to ionizing  

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

mechanisms and cellular consequences of low-dose exposure to ionizing mechanisms and cellular consequences of low-dose exposure to ionizing radiation Andrew J. Wyrobek 1 , Francesco Marchetti 1 , Xiu Lowe 1 , Xiaochen Lu 2 , Terumi Kohwi- Shigematsu 1 , Brian Davy 1 , Thomas E. Schmid 1 , Sylvia Ahn 1 , Tarlochan Nijjar 1 Matthew A. Coleman 2 , Contact information: ajwyrobek@gmail.com 1 Life Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 2 BioSciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA. The objectives of this research are to characterize the genome-wide molecular responses to low-dose ionizing radiation (<10cGy), to identify tissue and cell-type specific differences in pathways responses, and to identify the pivotal molecular pathway responses that control risks to genome integrity and health. This project utilizes mouse in

286

Standoff imaging of chemicals using IR spectroscopy  

SciTech Connect

Here we report on a standoff spectroscopic technique for identifying chemical residues on surfaces. A hand-held infrared camera was used in conjunction with a wavelength tunable mid-IR quantum cascade laser (QCL) to create hyperspectral image arrays of a target with an explosive residue on its surface. Spectral signatures of the explosive residue (RDX) were extracted from the hyperspectral image arrays and compared with a reference spectrum. Identification of RDX was achieved for residue concentrations of 20 g per cm2 at a distance of 1.5 m, and for 5 g per cm2 at a distance of 15 cm.

Senesac, Larry R [ORNL; Thundat, Thomas George [ORNL; Morales Rodriguez, Marissa E [ORNL

2011-01-01T23:59:59.000Z

287

Safety Around Sources of Radiation  

NLE Websites -- All DOE Office Websites (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).

288

Radiative Heating in Underexplored Bands Campaign (RHUBC)  

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

Bands Campaign (RHUBC) D. Turner and E. Mlawer RHUBC Breakout Session 2008 ARM Science Team Meeting 13 March, 2008 Norfolk, Virginia Motivation * Radiative heating/cooling in the mid-troposphere modulate the vertical motions of the atmosphere - This heating/cooling occurs primarily in water vapor absorption bands that are opaque at the surface * Approximately 40% of the OLR comes from the far-IR * Until recently, the observational tools were not available to evaluate the accuracy of the far-IR radiative transfer models - Spectrally resolved far-IR radiances, accurate PWV * Need to validate both clear sky (WV) absorption and cirrus scattering properties in these normally opaque bands Scientific Objectives * Conduct clear sky radiative closure studies in order to reduce uncertainties

289

Highly ionized atoms in tokamak discharges  

DOE Green Energy (OSTI)

Tokamak discharges are characterized by electron densities usually approximately 0.3 to 1.0 x 10/sup 14/ cm/sup -3/ and temperatures from a few hundred eV to several keV. In addition to the working gas (H or He), the plasma normally contains some light impurities (approximately 10/sup 12/ cm/sup -3/ O or C) that are completely stripped except at the outer periphery, and heavier elements from the vacuum wall and current-aperture limiter (Fe, Cr, Ni, W, Mo and others, approximately 10/sup 10/-10/sup 11/ cm/sup -3/) that remain partly stripped, hence relatively strongly radiating, throughout the discharge. Other elements, especially noble gases, may be deliberately added for diagnostic purposes. Resonance lines of Fe and Ar in the beryllium and lithium sequences, of Fe, Kr, and Mo in the magnesium and sodium sequences, and of Mo and Xe in the zinc and copper sequences have been used for rough determination of plasma composition. Since crucial plasma characteristics such as temperature and confinement time are sensitively affected by the local composition, it is essential to improve the available atomic data necessary for more accurate analysis: wavelengths, transition probabilities, excitation, ionization and recombination rates, especially for the heavier elements.

Hinnov, E.

1976-05-01T23:59:59.000Z

290

W51 IRS 2: A Massive Jet Emerging from a Molecular Cloud into an H II Region  

E-Print Network (OSTI)

We have mapped [Ne II] (12.8um) and [S IV] (10.5um) emission from W51 IRS 2 with TEXES on Gemini North, and we compare these data to VLA free-free observations and VLT near-infrared images. With 0.5" spatial and 4 km/s spectral resolution we are able to separate the ionized gas into several components: an extended H II region on the front surface of the molecular cloud, several embedded compact H II regions, and a streamer of high velocity gas. We interpret the high velocity streamer as a precessing or fan-like jet, which has emerged from the molecular cloud into an OB star cluster where it is being ionized.

J. H. Lacy; D. T. Jaffe; Q. Zhu; M. J. Richter; M. A. Bitner; T. K. Greathouse; K. Volk; T. R. Geballe; D. M. Mehringer

2007-02-13T23:59:59.000Z

291

Low Dose Radiation Program: Links - Current Issues Involving...  

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

of Ionizing Radiation A-Bombs Atomicarchive.com Hiroshima Peace site History of the Atomic Bomb & The Manhattan Project The Atomic Testing Museum The Race to Build the Atomic...

292

Low Dose Radiation Research Program: Mechanistic Modeling of...  

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

Laboratory Why This Project? Cells that are directly exposed to low doses of ionizing radiation may experience DNA damage. Cells which happen to be in the vicinity of the exposed...

293

Low Dose Radiation Research Program: James D. Tucker  

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

Role of the Adaptive Response in determining health risks from in vivo exposures to low dose of ionizing radiation Tucker, J. Publications Christian, A.T., Patte, M.S., Attix,...

294

Epidemiology of accidental radiation exposures  

Science Conference Proceedings (OSTI)

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

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

1996-05-01T23:59:59.000Z

295

RADIATION DETECTING AND TELEMETERING SYSTEM  

DOE Patents (OSTI)

A system is presented for measuring ionizing radiation at several remote stations and transmitting the measured information by radio to a central station. At each remote station a signal proportioned to the counting rate is applied across an electrical condenser made of ferroelectric material. The voltage across the condenser will vary as a function of the incident radiation and the capacitance of the condenser will vary accordingly. This change in capacitance is used to change the frequency of a crystalcontrolled oscillator. The output of the oscillator is coupled to an antenna for transmitting a signal proportional to the incident radiation.

Richards, H.K.

1959-12-15T23:59:59.000Z

296

IY:ILrnr IR-rl?l'  

Office of Legacy Management (LM)

IY:ILrnr IR-rl?l' IY:ILrnr IR-rl?l' w&m PadmmmTuJ tmml' aIs~#l!REm m-t, - 188kwxm BYI alahard 0. cr*rrror cy- r' , ' .~ -' - -' ^ , /' cs< 4. .c :' ; *. .h,- ' (z&&y .' ,/ ;f. .* &J >l a. L \' P" ,,,' ,.' I * :{' \ !' l t ..b c&~ tf ~ , r ,, r. ,* .;;;., k J ;, b $y$' Lrmprrw)rlt&tmxJ- a@. Frqrr at t&i8 raoLli:.y SC\ daummiI~Luualndr8rr~lfCUIf@@?~~oy-~ d )I t rq ,i .* 1 Virium~~bUrlJlOgarspvlr at ma rdutw. (500 p-4 3) i" 1 ) ,ip" 2. rt A8 - u %I* mm 4almpa~&rnbM Itrr+@# vbrp a** -y ;I11 ~*~~*- miw&mmwlrrwrbsr* ~rSthLtL,ort' tar,da*pcr¶.florllj pi &8~wl~cm@n-~ t#barwatla~r~tOf~. hwrl'r#tarr,urueunUr .--,U-L BirLl#a ofmml -vom. pe a ,Tjm-&,, i L) cc (. a 41 IA.9 #y7 /.& r*-rc * &ah&L- '2 , p-

297

NIST Ionizing Radiat. Div. - 2005-2007: Strategic Focus 2  

Science Conference Proceedings (OSTI)

... in the understanding of theories of evolution of ... smaller quantities of special nuclear materials than ... of a detector for photons with energies above 15 ...

298

Ionizing Radiation Div. 1995-1996 - Technical Highlights  

Science Conference Proceedings (OSTI)

... Experiments have already been done involving researchers from the University of Missouri-Columbia, Exxon, the Hahn-Meitner Institute (Berlin ...

299

NIST Ionizing Radiat. Div. - 2002: Strategic Focus 2  

Science Conference Proceedings (OSTI)

... at the NIST National Center for Neutron Research (NCNR) nuclear reactor. ... Spent fuel from nuclear reactors, weapons-grade plutonium, and certain ...

300

Recollections on Sixty Years of NBS Ionizing Radiation ...  

Science Conference Proceedings (OSTI)

... Pregnant Women (1977). 55 Protection of the Thyroid Gland in the Event of Releases of Radioiodine (1977). Volume 111 ...

2006-12-11T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

IONIZING RADIATION RISKS TO SATELLITE POWER SYSTEMS (SPS) WORKERS  

E-Print Network (OSTI)

g/cm for tne storm cellar to be used during solar particlea storm cellaris needed for space workers during a solar

Lyman, J.T.

2010-01-01T23:59:59.000Z

302

NIST Ionizing Radiation Safety Committee Initial Report of ...  

Science Conference Proceedings (OSTI)

... not perform a formal characterization analysis of ... powdered plutonium source contained only by a ... sources present in the inventory and approved in ...

2010-05-03T23:59:59.000Z

303

CELLULAR RESPONSES AT LOW DOSES OF IONIZING RADIATION  

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

and tissue levels including mutation induction and carcinogenesis. Furthermore, irradiation of the cytoplasm can initiate damage to the nucleus, and irradiated single cells...

304

Detection of Ionizing Radiation Using Graphene Field Effect Transistors  

E-Print Network (OSTI)

electrode, while the other electrode is the graphene layer. Applying a gate voltage, VG, field lines) of graphite, which has unique electronic properties [1]. Graphene has a high carrier mobility, about 10 times, and a layer of graphene on top (Fig. 2). The electric field is created by applying the gate voltage from

Chen, Yong P.

305

IONIZING RADIATION RISKS TO SATELLITE POWER SYSTEMS (SPS) WORKERS  

E-Print Network (OSTI)

belt intensity caused by geomagnetic substorms may result into the large amount of geomagnetic shielding available inL, denotes roughly a geomagnetic field line. The value gives

Lyman, J.T.

2010-01-01T23:59:59.000Z

306

IONIZING RADIATION RISKS TO SATELLITE POWER SYSTEMS (SPS) WORKERS  

E-Print Network (OSTI)

to develop long-term, baseload, electrical energy sourcesthe feasibility of generating baseload electrical power with

Lyman, J.T.

2010-01-01T23:59:59.000Z

307

NIST Ionizing Radiat. Div. - 2005-2007: Strategic Focus 1  

Science Conference Proceedings (OSTI)

... to develop and provide neutron standards and measurements needed for worker protection, nuclear power, homeland security, and fundamental ...

308

NIST Ionizing Radiat. Div. - 2005-2007: Strategic Focus 3  

Science Conference Proceedings (OSTI)

... NIST has established a satellite facility at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, to promote measurement accuracy for ...

309

NIST Ionizing Radiation Safety Committee Initial Report of ...  

Science Conference Proceedings (OSTI)

... to benefits, and the beneficial utilization of atomic and nuclear ... early market research; 23 ... into the storage cabinet, then charges a battery and leaves ...

2010-05-03T23:59:59.000Z

310

NIST Ionizing Radiat. Div. - 2002: Strategic Focus 1  

Science Conference Proceedings (OSTI)

... Two new CdZnTe detectors were tested, and their ability to detect gamma-ray emitting sources was compared with existing High-Purity ...

311

Humidity effects on calibrations of radiation therapy electrometers  

SciTech Connect

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

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

2012-02-15T23:59:59.000Z

312

Audible radiation monitor  

DOE Patents (OSTI)

This invention consists of a method and apparatus for monitoring ionizing radiation comprising radiation detectors in electrical connection with an isotopic analyzer and a device for producing chords to which each isotope is mapped so that the device produces a unique chord for each isotope. Preferably the chords are pleasing to the ear, except for chords representing unexpected isotopes, and are louder or softer depending on the level of radioactivity produced by each isotope, and musical instrument voices may be simulated in producing the chords as an aid to distinguishing similar-sounding chords. Because of the representation by chords, information regarding the level and composition of the radiation in an area can be conveyed to workers in that area more effectively and yet without distracting them.

Odell, D.M.C.

1992-12-31T23:59:59.000Z

313

Sample Desorption/Ionization From Mesoporous Silica  

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

Sample Desorption/Ionization From Mesoporous Silica Sample Desorption/Ionization From Mesoporous Silica Sample Desorption/Ionization From Mesoporous Silica Mesoporous silica is shown to be a sample holder for laser desorption/ionization of mass spectrometry. Available for thumbnail of Feynman Center (505) 665-9090 Email Sample Desorption/Ionization From Mesoporous Silica Mesoporous silica is shown to be a sample holder for laser desorption/ionization of mass spectrometry. Supported mesoporous silica was prepared by coating an ethanolic silicate solution having a removable surfactant onto a substrate to produce a self-assembled, ordered, nanocomposite silica thin film. The surfactant was chosen to provide a desired pore size between about 1 nanometer diameter and 50 nanometers diameter. Removal of the surfactant resulted in a mesoporous silica thin

314

The effect of microhydration on ionization energies of thymine  

Science Conference Proceedings (OSTI)

A combined theoretical and experimental study of the effect of microhydration on ionization energies (IEs) of thymine is presented. The experimental IEs are derived from photoionization efficiency curves recorded using tunable synchrotron VUV radiation. The onsets of the PIE curves are 8.85+-0.05, 8.60+-0.05, 8.55+-0.05, and 8.40+-0.05 eV for thymine, thymine mono-, di-, and tri-hydrates, respectively. The computed (EOM-IP-CCSD/cc-pVTZ) AIEs are 8.90, 8.51, 8.52, and 8.35 eV for thymine and the lowest isomers of thymine mono-, di-, and tri-hydrates. Due to large structural relaxation, the Franck-Condon factors for the 0water molecule reduces the first vertical IE by 0.10-0.15 eV. The adiabatic IE decreases even more (up to 0.4 eV). The magnitude of the effect varies for different ionized states and for different isomers. For the ionized states that are localized on thymine the dominant contribution to the IE reduction is the electrostatic interaction between the delocalized positive charge on thymine and the dipole moment of the water molecule.

Khistyev, Kirill; Bravaya, Ksenia B.; Kamarchik, Eugene; Kostko, Oleg; Ahmed, Musahid; Krylov, Anna I.

2011-01-03T23:59:59.000Z

315

The effect of microhydration on ionization energies of thymine  

SciTech Connect

A combined theoretical and experimental study of the effect of microhydration on ionization energies (IEs) of thymine is presented. The experimental IEs are derived from photoionization efficiency curves recorded using tunable synchrotron VUV radiation. The onsets of the PIE curves are 8.85+-0.05, 8.60+-0.05, 8.55+-0.05, and 8.40+-0.05 eV for thymine, thymine mono-, di-, and tri-hydrates, respectively. The computed (EOM-IP-CCSD/cc-pVTZ) AIEs are 8.90, 8.51, 8.52, and 8.35 eV for thymine and the lowest isomers of thymine mono-, di-, and tri-hydrates. Due to large structural relaxation, the Franck-Condon factors for the 0<-- 0 transitions are very small shifting the apparent PIE onsets to higher energies. Microsolvation strongly affects IEs of thymine -- addition of each water molecule reduces the first vertical IE by 0.10-0.15 eV. The adiabatic IE decreases even more (up to 0.4 eV). The magnitude of the effect varies for different ionized states and for different isomers. For the ionized states that are localized on thymine the dominant contribution to the IE reduction is the electrostatic interaction between the delocalized positive charge on thymine and the dipole moment of the water molecule.

Khistyev, Kirill; Bravaya, Ksenia B.; Kamarchik, Eugene; Kostko, Oleg; Ahmed, Musahid; Krylov, Anna I.

2011-01-03T23:59:59.000Z

316

High-resolution ionization detector and array of such detectors  

DOE Patents (OSTI)

A high-resolution ionization detector and an array of such detectors are described which utilize a reference pattern of conductive or semiconductive material to form interaction, pervious and measurement regions in an ionization substrate of, for example, CdZnTe material. The ionization detector is a room temperature semiconductor radiation detector. Various geometries of such a detector and an array of such detectors produce room temperature operated gamma ray spectrometers with relatively high resolution. For example, a 1 cm.sup.3 detector is capable of measuring .sup.137 Cs 662 keV gamma rays with room temperature energy resolution approaching 2% at FWHM. Two major types of such detectors include a parallel strip semiconductor Frisch grid detector and the geometrically weighted trapezoid prism semiconductor Frisch grid detector. The geometrically weighted detector records room temperature (24.degree. C.) energy resolutions of 2.68% FWHM for .sup.137 Cs 662 keV gamma rays and 2.45% FWHM for .sup.60 Co 1.332 MeV gamma rays. The detectors perform well without any electronic pulse rejection, correction or compensation techniques. The devices operate at room temperature with simple commercially available NIM bin electronics and do not require special preamplifiers or cooling stages for good spectroscopic results.

McGregor, Douglas S. (Ypsilanti, MI); Rojeski, Ronald A. (Pleasanton, CA)

2001-01-16T23:59:59.000Z

317

Ionization Energies, Electron Affinities and Electronegativies ... - TMS  

Science Conference Proceedings (OSTI)

Jun 28, 2007 ... Periodic table of the elements containing ionization energies, electron affinities, and electronegativities. CITATION: : R.E. Dickerson, H.B. Gray...

318

Hall Magnetohydrodynamics of weakly-ionized plasma  

E-Print Network (OSTI)

We show that the Hall scale in a weakly ionized plasma depends on the fractional ionization of the medium and, Hall MHD description becomes important whenever the ion-neutral collision frequency is comparable to the ion-gyration frequency, or, the ion-neutral collisional mean free path is smaller than the ion gyro-radius. Wave properties of a weakly-ionized plasma also depends on the fractional ionization and plasma Hall parameters, and whistler mode is the most dominant mode in such a medium. Thus Hall MHD description will be important in astrophysical disks, dark molecular clouds, neutron star crusts, and, solar and planetary atmosphere.

B. P. Pandey; Mark Wardle

2006-08-01T23:59:59.000Z

319

Low-Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer  

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

Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer Bobby R. Scott, Ph.D. and Jennifer D. Di Palma Lovelace Respiratory Research Institute, 2425 Ridgecrest Drive SE Albuquerque, NM 87108 USA Life on earth evolved in a low-level ionizing radiation environment comprised of terrestrial radiation and cosmic rays. Today we all reside in an ionizing radiation environment comprised of both natural background radiation and radiation from human activities (e.g., Chernobyl accident). An evolutionary benefit of the interaction of low-level, low linear-energy-transfer (LET) ionizing radiation with mammalian life forms on earth is adapted protection. Adapted protection involves low-dose/dose-rate, low-LET radiation induced high-fidelity DNA repair in cooperation with normal apoptosis (presumed p53

320

Low Dose Radiation Research Program: Earlier Events  

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

Earlier Events Earlier Events 2000 | 2001 | 2002 | 2003 | 2004 April 2000 Ionizing Radiation Science and Protection in the 21st Century, NCRP, April 5-6, Arlington, VA. RADIATION RESEARCH 2000, Association for Radiation Research, April 10-12, Bristol, UK. Florida Chapter of the Health Physics Society Spring 2000 Meeting, Gainesville, FL, April 13-14. 47th Annual Meeting of the Radiation Research Society, April 29-May 3, Albuquerque, NM. May 2000 IRPA-10 International Congress 2000, May 14-19, Hiroshima, Japan. IRPA-10 Secretariat, c/o Japan Convention Services, Inc., Nippon Press Center Building, 2-2-1, Uchisaiwai-cho, Chiyoda-ku, Tokyo 100, Japan. Phone: 81-3-3508-1214. Fax: 81-3-3508-0820. irpa10@convention.jp. 4th International Non-Ionizing Radiation Workshop, May 22-25, Kyoto,

Note: This page contains sample records for the topic "ionizing radiation ir" 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

Low radiative efficiency accretion at work in active galactic nuclei: the nuclear spectral energy distribution of NGC4565  

E-Print Network (OSTI)

We derive the spectral energy distribution (SED) of the nucleus of the Seyfert galaxy NGC4565. Despite its classification as a Seyfert2, the nuclear source is substantially unabsorbed. The absorption we find from Chandra data (N_H=2.5 X 10^21 cm^-2) is consistent with that produced by material in the galactic disk of the host galaxy. HST images show a nuclear unresolved source in all of the available observations, from the near-IR H band to the optical U band. The SED is completely different from that of Seyfert galaxies and QSO, as it appears basically ``flat'' in the IR-optical region, with a small drop-off in the U-band. The location of the object in diagnostic planes for low luminosity AGNs excludes a jet origin for the optical nucleus, and its extremely low Eddington ratio L_o/L_Edd indicates that the radiation we observe is most likely produced in a radiatively inefficient accretion flow (RIAF). This would make NGC4565 the first AGN in which an ADAF-like process is identified in the optical. We find that the relatively high [OIII] flux observed from the ground cannot be all produced in the nucleus. Therefore, an extended NLR must exist in this object. This may be interpreted in the framework of two different scenarios: i) the radiation from ADAFs is sufficient to give rise to high ionization emission-line regions through photoionization, or ii) the nuclear source has recently ``turned-off'', switching from a high-efficiency accretion regime to the present low-efficiency state.

M. Chiaberge; R. Gilli; F. D. Macchetto; W. B. Sparks

2006-01-27T23:59:59.000Z

322

IRS Private Letter Rulings and Technical Advice Memoranda | Data...  

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

digital@treasury.gov Unique Identifier TREAS-4433 Public Access Level public Data Dictionary http:www.irs.govtaxexemptbondarticle0,,id134365,00.html Data Download URL...

323

Intensity-resolved Above Threshold Ionization Yields of Atoms with Ultrashort Laser Pulses  

E-Print Network (OSTI)

The above threshold ionization (ATI) spectra provide a diversity of information about a laser-atom ionization process such as laser intensity, pulse duration, carrier envelope phase, and atomic energy level spacing. However, the spatial distribution of intensities inherent in all laser beams reduces the resolution of this information. This research focuses on recovering the intensity-resolved ATI spectra from experimental data using a deconvolution algorithm. Electron ionization yields of xenon were measured for a set of laser pulse intensities using a time of flight (TOF) setup. Horizontally polarized, unchirped, 50fs pulses were used in the ionization process. All laser parameters other than the radiation intensity were held constant over the set of intensity measurements. A deconvolution algorithm was developed based on the experimental parameters. Then the deconvolution algorithm was applied to the experimental data to obtain the intensity-resolved total yield probability and ATI spectra. Finally, an error analysis was performed to determine the stability and accuracy of the algorithm as well as the quality of the data. It was found that the algorithm produced greater contrast for peaks in the ATI spectra where atom specific resonant behavior is observed. Additionally, the total yield probability showed that double ionization may be observed in the ionization yield. The error analysis revealed that the algorithm was stable under the experimental conditions for a range of intensities.

Hart, Nathan Andrew

2011-08-01T23:59:59.000Z

324

Method for the depth corrected detection of ionizing events from a co-planar grids sensor  

DOE Patents (OSTI)

A method for the detection of ionizing events utilizing a co-planar grids sensor comprising a semiconductor substrate, cathode electrode, collecting grid and non-collecting grid. The semiconductor substrate is sensitive to ionizing radiation. A voltage less than 0 Volts is applied to the cathode electrode. A voltage greater than the voltage applied to the cathode is applied to the non-collecting grid. A voltage greater than the voltage applied to the non-collecting grid is applied to the collecting grid. The collecting grid and the non-collecting grid are summed and subtracted creating a sum and difference respectively. The difference and sum are divided creating a ratio. A gain coefficient factor for each depth (distance between the ionizing event and the collecting grid) is determined, whereby the difference between the collecting electrode and the non-collecting electrode multiplied by the corresponding gain coefficient is the depth corrected energy of an ionizing event. Therefore, the energy of each ionizing event is the difference between the collecting grid and the non-collecting grid multiplied by the corresponding gain coefficient. The depth of the ionizing event can also be determined from the ratio.

De Geronimo, Gianluigi (Syosset, NY); Bolotnikov, Aleksey E. (South Setauket, NY); Carini, Gabriella (Port Jefferson, NY)

2009-05-12T23:59:59.000Z

325

About Radiation  

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

Radiation What is radiation? Radiation is a form of energy that is a part of our everyday lives. All of us receive a "dose" of radiation each day. Most of the dose comes from...

326

Geant4 applications in the heliospheric radiation environment  

E-Print Network (OSTI)

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

Pedro Brogueira; Patrcia Gonalves; Ana Keating; Dalmiro Maia; Mrio Pimenta; Bernardo Tom

2007-09-11T23:59:59.000Z

327

A 3D Monte Carlo Photoionization Code for Modeling Diffuse Ionized Gas  

E-Print Network (OSTI)

We have developed a three dimensional Monte Carlo photoionization code tailored for the study of Galactic H II regions and the percolation of ionizing photons in diffuse ionized gas. We describe the code, our calculation of photoionization, heating & cooling, and the approximations we have employed for the low density H II regions we wish to study. Our code gives results in agreement with the Lexington H II region benchmarks. We show an example of a 2D shadowed region and point out the very significant effect that diffuse radiation produced by recombinations of helium has on the temperature within the shadow.

Wood, K; Ercolano, B

2004-01-01T23:59:59.000Z

328

Ionization tube simmer current circuit  

DOE Patents (OSTI)

A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current.

Steinkraus, Jr., Robert F. (Livermore, CA)

1994-01-01T23:59:59.000Z

329

Ionization tube simmer current circuit  

DOE Patents (OSTI)

A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current. 6 figures.

Steinkraus, R.F. Jr.

1994-12-13T23:59:59.000Z

330

Approximations for radiative cooling and heating in the solar chromosphere  

E-Print Network (OSTI)

Context. The radiative energy balance in the solar chromosphere is dominated by strong spectral lines that are formed out of LTE. It is computationally prohibitive to solve the full equations of radiative transfer and statistical equilibrium in 3D time dependent MHD simulations. Aims. To find simple recipes to compute the radiative energy balance in the dominant lines under solar chromospheric conditions. Methods. We use detailed calculations in time-dependent and 2D MHD snapshots to derive empirical formulae for the radiative cooling and heating. Results. The radiative cooling in neutral hydrogen lines and the Lyman continuum, the H and K and intrared triplet lines of singly ionized calcium and the h and k lines of singly ionized magnesium can be written as a product of an optically thin emission (dependent on temperature), an escape probability (dependent on column mass) and an ionization fraction (dependent on temperature). In the cool pockets of the chromosphere the same transitions contribute to the heat...

Carlsson, Mats

2012-01-01T23:59:59.000Z

331

Low Dose Radiation Research Program: Genetic Factors Affecting  

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

Genetic Factors Affecting Susceptibility to Low-Doses of Ionizing Genetic Factors Affecting Susceptibility to Low-Doses of Ionizing Radiation. Authors: William F. Morgan, Pat Concannon & John H.J. Petrini The goal of this program is to test the hypothesis that mice heterozygous for the NBS1 gene are genetically susceptible to low doses of ionizing radiation. Patients with Nijmegen Breakage Syndrome (NBS) are radiation sensitive, because of defects in cellular responses to radiation induced genetic damage. It is unclear whether humans heterozygous for the mutations associated with NBS are radiation sensitive and results from cell culture experiments give conflicting results. In collaboration with John Petrini at the Memorial Sloan Kettering Cancer Center in New York City we developed a mouse model of this disorder and are directly testing the hypothesis

332

Health Risks Associated with Low Doses of Radiation  

Science Conference Proceedings (OSTI)

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

1994-09-17T23:59:59.000Z

333

Scaling IR-system evaluation using term relevance sets  

Science Conference Proceedings (OSTI)

This paper describes an evaluation method based on Term Relevance Sets Trels that measures an IR system's quality by examining the content of the retrieved results rather than by looking for pre-specified relevant pages. Trels consist of a list ... Keywords: IR-system evaluation, keywords, trels, web search evaluation

Einat Amitay; David Carmel; Ronny Lempel; Aya Soffer

2004-07-01T23:59:59.000Z

334

FT-IR photoacoustic spectroscopy investigation of oxidized wool  

SciTech Connect

The Fourier transform infrared photoacoustic spectra (FT-IR/PAS) of wool, shrink-resist treated wool and corona discharge oxidized wool are reported. Products of the oxidation of wool by dichloroisocyanuric acid are discussed. The FT-IR/PAS results indicate the formation of a sulphinic acid residue during the wool treatment.

McKenna, W.P.; Gale, D.J.; Rivett, D.E.; Eyring, E.M.

1985-02-01T23:59:59.000Z

335

RADIATION: A TOOL FOR INDUSTRY. A Survey of Current Technology  

SciTech Connect

This one-year survey of industrial applications of ionizing radiation is based on interviews with workers in the field and on analysis of selected literature. ionizing radiation at kilowatt power levels from electron accelerators and from radionuclides is finding a few special applications, notably sterilization and be in various stages of process development and tcsting. These are concentrated heavily in the plastics field, though examples are found in petrochemical synthesis, product sterilization, and portable energy sources such as batteries. Ionizing radiation is not yet a processing tool of major importance to industry generally, however, because it has not yet demonstrated sufficient advantages over established methods of achieving a similar result. Thus, though ionizing radiation produces free radicals under a wide variety of conditions, it has, with few exceptions, not proved superior to other agents, such as heat and chemicals, that also produce free radicals. Insufficient specificity of action, low yields, and costs higher than those of competitive processes are among the chief difficulties found. Possible unique features of radiation have not been fully explored. Optimization of enviromental variables has not been thoroughly studied. Indirect advantages associated with radiation, such as greater processing or packaging flexibility, have already proved significantly important but have not yet been thoroughly evaluated in most potential applications. Even radiation engineering is relatively undeveloped and radiation economics uncertain. Skillfully oriented research and development on such problems will improve the likelihood of radiation becoming a tool of major importance for U.S. industry. (auth)

1959-01-01T23:59:59.000Z

336

Pigments which reflect infrared radiation from fire  

DOE Patents (OSTI)

Conventional paints transmit or absorb most of the intense infrared (IR) radiation emitted by fire, causing them to contribute to the spread of fire. The present invention comprises a fire retardant paint additive that reflects the thermal IR radiation emitted by fire in the 1 to 20 micrometer ({micro}m) wavelength range. The important spectral ranges for fire control are typically about 1 to about 8 {micro}m or, for cool smoky fires, about 2 {micro}m to about 16 {micro}m. The improved inventive coatings reflect adverse electromagnetic energy and slow the spread of fire. Specific IR reflective pigments include titanium dioxide (rutile) and red iron oxide pigments with diameters of about 1 {micro}m to about 2 {micro}m and thin leafing aluminum flake pigments. 4 figs.

Berdahl, P.H.

1998-09-22T23:59:59.000Z

337

Nevada Test Site Radiation Protection Program  

Science Conference Proceedings (OSTI)

Title 10 Code of Federal Regulations (CFR) 835, 'Occupational Radiation Protection', establishes radiation protection standards, limits, and program requirements for protecting individuals from ionizing radiation resulting from the conduct of U.S. Department of Energy (DOE) activities. 10 CFR 835.101(a) mandates that DOE activities be conducted in compliance with a documented Radiation Protection Program (RPP) as approved by DOE. This document promulgates the RPP for the Nevada Test Site (NTS), related (onsite or offsite) DOE National Nuclear Security Administration Nevada Site Office (NNSA/NSO) operations, and environmental restoration offsite projects.

Radiological Control Managers' Council, Nevada Test Site

2007-08-09T23:59:59.000Z

338

Alpha Radiation  

NLE Websites -- All DOE Office Websites (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.

339

AREA RADIATION MONITOR  

DOE Patents (OSTI)

S>An improved area radiation dose monitor is designed which is adapted to compensate continuously for background radiation below a threshold dose rate and to give warning when the dose integral of the dose rate of an above-threshold radiation excursion exceeds a selected value. This is accomplished by providing means for continuously charging an ionization chamber. The chamber provides a first current proportional to the incident radiation dose rate. Means are provided for generating a second current including means for nulling out the first current with the second current at all values of the first current corresponding to dose rates below a selected threshold dose rate value. The second current has a maximum value corresponding to that of the first current at the threshold dose rate. The excess of the first current over the second current, which occurs above the threshold, is integrated and an alarm is given at a selected integrated value of the excess corresponding to a selected radiation dose. (AEC)

Manning, F.W.; Groothuis, S.E.; Lykins, J.H.; Papke, D.M.

1962-06-12T23:59:59.000Z

340

Remote radiation dosimetry  

DOE Patents (OSTI)

Disclosed are methods and apparatus for remotely measuring radiation levels. Such are particularly useful for measuring relatively high levels or dosages of radiation being administered in radiation therapy. They are also useful for more general radiation level measurements where remote sensing from the remaining portions of the apparatus is desirable. The apparatus uses a beam generator, such as a laser beam, to provide a stimulating beam. The stimulating beam is preferably of wavelengths shorter than 6 microns, or more advantageously less than 2 microns. The stimulating beam is used to stimulate a remote luminescent sensor mounted in a probe which emits stored luminescent energy resulting from exposure of the sensor to ionizing radiation. The stimulating beam is communicated to the remote luminescent sensor via transmissive fiber which also preferably serves to return the emission from the luminescent sensor. The stimulating beam is advantageously split by a beam splitter to create a detector beam which is measured for power during a reading period during which the luminescent phosphor is read. The detected power is preferably used to control the beam generator to thus produce desired beam power during the reading period. The luminescent emission from the remote sensor is communicated to a suitable emission detector, preferably after filtering or other selective treatment to better isolate the luminescent emission.

Braunlich, Peter F. (Pullman, WA); Tetzlaff, Wolfgang (Pullman, WA); Hegland, Joel E. (Pullman, WA); Jones, Scott C. (Pullman, WA)

1991-01-01T23:59:59.000Z

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


341

Remote radiation dosimetry  

DOE Patents (OSTI)

Disclosed are methods and apparatus for remotely measuring radiation levels. Such are particularly useful for measuring relatively high levels or dosages of radiation being administered in radiation therapy. They are also useful for more general radiation level measurements where remote sensing from the remaining portions of the apparatus is desirable. The apparatus uses a beam generator, such as a laser beam, to provide a stimulating beam. The stimulating beam is preferably of wavelengths shorter than 6 microns, or more advantageously less than 2 microns. The stimulating beam is used to stimulate a remote luminescent sensor mounted in a probe which emits stored luminescent energy resulting from exposure of the sensor to ionizing radiation. The stimulating beam is communicated to the remote luminescent sensor via a transmissive fiber which also preferably serves to return the emission from the luminescent sensor. The stimulating beam is advantageously split by a beam splitter to create a detector beam which is measured for power during a reading period during which the luminescent phosphor is read. The detected power is preferably used to control the beam generator to thus produce desired beam power during the reading period. The luminescent emission from the remote sensor is communicated to a suitable emission detector, preferably after filtering or other selective treatment to better isolate the luminescent emission. 8 figures.

Braunlich, P.F.; Tetzlaff, W.; Hegland, J.E.; Jones, S.C.

1991-03-12T23:59:59.000Z

342

NIST Ground Levels and Ionization Energies for the Neutral ...  

Science Conference Proceedings (OSTI)

The ionization energies in the table are based on a recent survey of ... cited compilation gives the reference(s) for the original ionization-energy data. ...

2013-09-16T23:59:59.000Z

343

RADIATION DOSIMETER AND DOSIMETRIC METHODS  

DOE Patents (OSTI)

The determination of ionizing radiation by means of single fluid phase chemical dosimeters of the colorimetric type is presented. A single fluid composition is used consisting of a chlorinated hydrocarbon, an acidimetric dye, a normalizer and water. Suitable chlorinated hydrocarbons are carbon tetrachloride, chloroform, trichloroethylene, trichlorethane, ethylene dichioride and tetracbloroethylene. Suitable acidimetric indicator dyes are phenol red, bromcresol purple, and creosol red. Suitable normallzers are resorcinol, geraniol, meta cresol, alpha -tocopberol, and alpha -naphthol.

Taplin, G.V.

1958-10-28T23:59:59.000Z

344

Photodetectors with passive thermal radiation control  

DOE Patents (OSTI)

A new class of photodetectors which include means for passive shielding against undesired thermal radiation is disclosed. Such devices can substitute in applications currently requiring cooled optical sensors, such as IR detection and imaging. This description is included for purposes of searching, and is not intended to limit or otherwise influence the interpretation of the present invention.

Lin, Shawn-Yu (Albuquerque, NM); Fleming, James G. (Albuquerque, NM); Dodson, Brian W. (Albuquerque, NM)

2001-10-02T23:59:59.000Z

345

Radiation: Radiation Control (Indiana)  

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

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

346

Low Dose Radiation Program: Workshop VI Abstracts  

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

Workshop VI Principal Investigator and Abstracts Workshop VI Principal Investigator and Abstracts Anderson, Carl Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Application to p53 and Low Dose Ionizing Radiation. Averbeck, Dietrich Cellular Responses at Low Doses of Ionizing Radiation. Azzam, Edouard Adaptive Responses to Low Dose/Low Dose-Rate ?-Rays in Normal Human Fibroblasts: The Role of Oxidative Metabolism. Bailey, Susan The Role of Telomere Dysfunction in Driving Genomic Instability. Balajee, Adayabalam Low Dose Radiation Induced DNA Damage Signaling and Repair Responses in Human 3-Dimensional Skin Model System. Barcellos-Hoff, Mary Helen Imaging Bioinformatics for Mapping Multidimensional Responses. Barcellos-Hoff, Mary Helen Biological Response to Radiation Mediated through the Microenvironment and

347

THE EFFECTS OF IONIZING RADIATIONS ON PERIPHERAL NERVE. PART I. THE EFFECTS OF IN SITU X-IRRADIATION ON MAMMALIAN NERVE ACTION POTENTIAL. PART II. ALTERATION OF RESTING, ACTION AND LOCAL POTENTIALS OF CRAYFISH GIANT AXONS BY UV IRRADIATION. Progress Report, 1959-1960  

SciTech Connect

Progress is reported in studies on the sensitivity of nerves to exposure to x and ultraviolet radiation. Findings are reported on the response of the sciatic nerve of cats exposed in situ to x radiation and on the response of crayfish giant axons exposed to ultraviolet radiation. Data are presented graphically and results are discussed. (C.H.)

Duvall, C.P.; Gasteiger, E.L.; Daube, J.R.

1960-10-31T23:59:59.000Z

348

Dissociative ionization of H{sub 2} in an attosecond pulse train and delayed laser pulse  

SciTech Connect

The ionization of H{sub 2} in a single attosecond extreme ultraviolet (XUV) pulse generates a nuclear wave packet in H{sub 2}{sup +}, which is entangled with the emitted photoelectron wave packet. The nuclear wave-packet dynamics can be observed by dissociating H{sub 2}{sup +} in a delayed IR laser pulse. If H{sub 2} is ionized by a sequence of XUV pulses of an attosecond pulse train, whether or not the corresponding sequence of nuclear wave packets in H{sub 2}{sup +} is detected as a coherent or incoherent superposition depends on whether and how the photoelectrons are observed. We simulate the nuclear dynamics in this XUV-pump-IR-probe scenario and analyze our numerical results for both single attosecond pump pulses and pump-pulse trains of different lengths and temporal spacings between individual XUV pulses. By superimposing nuclear wave packets in H{sub 2}{sup +} generated by individual pulses in the pump-pulse train incoherently, we calculate proton kinetic energy release spectra that are in good qualitative agreement with the recent experiment of Kelkensberg et al. [Phys. Rev. Lett. 103, 123005 (2009)].

He Feng; Thumm, Uwe [James R. Macdonald Laboratory, Kansas State University, Manhattan, Kansas 66506-2604 (United States)

2010-05-15T23:59:59.000Z

349

Charged-Particle Impact Ionization of Atoms  

Science Conference Proceedings (OSTI)

We have developed a hybrid method to treat charged-particle impact ionization of complex atoms and ions. The essential idea is to describe the interaction between a fast projectile and the target perturbatively, up to second order, while the initial bound state and the ejected-electron--residual-ion interaction can be handled via a convergent R-matrix with pseudo-states (close-coupling) expansion. Example results for ionization of the heavy noble gases (Ne-Xe) by positron and electron impact are presented. The general scheme for a distorted-wave treatment of ionization by heavy-particle impact is described.

Bartschat, Klaus; Guan Xiaoxu [Department of Physics and Astronomy, Drake University, Des Moines, IA 50311 (United States)

2008-08-08T23:59:59.000Z

350

Radiation Transport in Takamak Edge Plasmas  

DOE Green Energy (OSTI)

Plasmas in edge regions of tokamaks can be very optically thick to hydrogen lines. Strong line radiation introduces a non-local coupling between different regions of the plasma and can significantly affect the ionization and energy balance. These effects can be very important, but they are not included in current edge plasma simulations. We report here on progress in self-consistently including the effects of a magnetic field, line radiation and plasma transport in modeling tokamak edge plasmas.

Scott, H; Adams, M

2002-09-30T23:59:59.000Z

351

Medical Applications of Synchrotron Radiation  

DOE R&D Accomplishments (OSTI)

Ever since the first diagnostic x-ray was done in the United States on February 3, 1896, the application of ionizing radiation to the field of medicine has become increasingly important. Both in clinical medicine and basic research the use of x-rays for diagnostic imaging and radiotherapy is now widespread. Radiography, angiography, CAT and PETT scanning, mammography, and nuclear medicine are all examples of technologies developed to image the human anatomy. In therapeutic applications, both external and internal sources of radiation are applied to the battle against cancer. The development of dedicated synchrotron radiation sources has allowed exciting advances to take place in many of these applications. The new sources provide tunable, high-intensity monochromatic beams over a wide range of energies which can be tailored to specific programmatic needs. This paper surveys those areas of medical research in which synchrotron radiation facilities are actively involved.

Thomlinson, W.

1991-10-00T23:59:59.000Z

352

Medical applications of synchrotron radiation  

SciTech Connect

Ever since the first diagnostic x-ray was done in the United States on February 3, 1896, the application of ionizing radiation to the field of medicine has become increasingly important. Both in clinical medicine and basic research the use of x-rays for diagnostic imaging and radiotherapy is now widespread. Radiography, angiography, CAT and PETT scanning, mammography, and nuclear medicine are all examples of technologies developed to image the human anatomy. In therapeutic applications, both external and internal sources of radiation are applied to the battle against cancer. The development of dedicated synchrotron radiation sources has allowed exciting advances to take place in many of these applications. The new sources provide tunable, high-intensity monochromatic beams over a wide range of energies which can be tailored to specific programmatic needs. This paper surveys those areas of medical research in which synchrotron radiation facilities are actively involved.

Thomlinson, W.

1991-10-01T23:59:59.000Z

353

A numerical scheme for ionizing shock waves  

Science Conference Proceedings (OSTI)

A two-dimensional (2D) visual computer code to solve the steady state (SS) or transient shock problems including partially ionizing plasma is presented. Since the flows considered are hypersonic and the resulting temperatures are high, the plasma is ...

Necdet Aslan; Michael Mond

2005-12-01T23:59:59.000Z

354

Theory of electron transfer and ionization  

DOE Green Energy (OSTI)

The main effort reported is directed toward charge transfer and ionization in high energy atomic collisions. The research may be divided into classical trajectory calculations, quantum - mechanical collision theory, and phenomenological treatments of quantal interference effects in heavy ion collisions.

Becker, R.L.

1979-01-01T23:59:59.000Z

355

Non-equilibrium hydrogen ionization in 2D simulations of the solar atmosphere  

E-Print Network (OSTI)

The ionization of hydrogen in the solar chromosphere and transition region does not obey LTE or instantaneous statistical equilibrium because the timescale is long compared with important hydrodynamical timescales, especially of magneto-acoustic shocks. We implement an algorithm to compute non-equilibrium hydrogen ionization and its coupling into the MHD equations within an existing radiation MHD code, and perform a two-dimensional simulation of the solar atmosphere from the convection zone to the corona. Analysis of the simulation results and comparison to a companion simulation assuming LTE shows that: a) Non-equilibrium computation delivers much smaller variations of the chromospheric hydrogen ionization than for LTE. The ionization is smaller within shocks but subsequently remains high in the cool intershock phases. As a result, the chromospheric temperature variations are much larger than for LTE because in non-equilibrium, hydrogen ionization is a less effective internal energy buffer. The actual shock temperatures are therefore higher and the intershock temperatures lower. b) The chromospheric populations of the hydrogen n = 2 level, which governs the opacity of Halpha, are coupled to the ion populations. They are set by the high temperature in shocks and subsequently remain high in the cool intershock phases. c) The temperature structure and the hydrogen level populations differ much between the chromosphere above photospheric magnetic elements and above quiet internetwork. d) The hydrogen n = 2 population and column density are persistently high in dynamic fibrils, suggesting that these obtain their visibility from being optically thick in Halpha also at low temperature.

J. Leenaarts; M. Carlsson; V. Hansteen; R. J. Rutten

2007-09-24T23:59:59.000Z

356

Gas amplified ionization detector for gas chromatography  

DOE Patents (OSTI)

A gas-amplified ionization detector for gas chromatography which possesses increased sensitivity and a very fast response time is described. Solutes eluding from a gas chromatographic column are ionized by uv photoionization of matter eluting therefrom. The detector is capable of generating easily measured voltage signals by gas amplification/multiplication of electron products resulting from the uv photoionization of at least a portion of each solute passing through the detector. 4 figs.

Huston, G.C.

1989-11-27T23:59:59.000Z

357

Beta Radiation  

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

Beta Radiation 1. Beta radiation may travel meters in air and is moderately penetrating. 2. Beta radiation can penetrate human skin to the "germinal layer," where new skin cells...

358

RADIATION MONITORING  

E-Print Network (OSTI)

of Monitoring for Radiation Protection of Workers" in ICRPNo. 9, in "Advances in Radiation Protection and Dosimetry inDosimetry f o r Stray Radiation Monitoring on the CERN S i t

Thomas, R.H.

2010-01-01T23:59:59.000Z

359

Radiative Importance of ThinŽ Liquid Water Clouds  

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

Program Program Accomplishments of the Instantaneous Radiative Flux (IRF) Working Group August 2006 AERI Observations at Southern Great Plains Improve Infrared Radiative Transfer Models Turner et al., JAS, 2004 * AERI observations used to evaluate clear sky IR radiative transfer models * Long-term comparisons have improved - Spectral line database parameters - Water vapor continuum absorption models * Reduced errors in computation of downwelling radiative IR flux by approx 4; current uncertainty is on the order of 1.5 W/m 2 AERI - (Pre-ARM Model) AERI - (Model in 2003) 1 RU = 1 mW / (m 2 sr cm -1 ) Excellent Agreement in Clear Sky Shortwave Radiative Transfer Between Obs and Calcs Shortwave Flux Bias (Solid) Shortwave Flux RMS (Hatched) W m -2 * Comparison of shortwave radiative flux at the surface

360

AN IONIZATION CHAMBER LAUNDRY MONITOR  

SciTech Connect

The determination of the amount of contamination remaining on a garment after it has been washed is an important part of hot laundry operations. In the past garments were monitored by measuring the contamination concentrated in the crotch with a GM tube probe. This type of spot check does not detect any isolated hot spots on other pants of the garment. To monitor the entire garment with a GM tube instrument is excessively time consuming for a large number of garments. To overcome these difficulties a sensitive, large-volume ionization chamber was constructed. It is rectangular in shape, 5 ft high by 2 1/2 ft wide by 4 in. deep. The center electrode is of a grid type and is mounted halfway between the front window and the back of the chamber. In a 0.5-mr/hr field, 180 v is sufficient to saturate toe chamber. In order to insure beta sensitivity, the front window has an equivalent thickness of approximately 7 mg/cm/sup 2/. The measuring device is a line-operated electrometer circuit equipped with an alarm that may be set at the rejection limit for the type of garment being monitored. A fullscale deflection on the most sensitive range is given by 2 to 3 mu C of liquid mixed fission products deposited on a garment. Since the chamber monitors the entire garment, the results are independent of the location of the contarnination. In practice, garments may be monitored at the rate of 7 per min, while only 3 per min may be completely checked with a GM tube probs. Field tests indicate that this instrument is stable and trouble free. Background causes a meter deflection of about 20 divisions, which is low enough to give reliable accuracy for monitoring garments. (auth)

Chester, J.D.; Handloser, J.S.

1958-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

Combination of Manually Digitized Radar and GOES IR for Real-Time Display of Rainfall Intensity  

Science Conference Proceedings (OSTI)

Manually Digitized Radar (MDR) and Geostationary Operational Environmental Satellite (GOES) thermal infrared (IR) data were merged to form a higher-resolution radar/IR product than that represented by the MDR. The combination MDR/IR maps were ...

Paul H. Heinemann; J. David Martsolf; John F. Gerber; Daniel L. Smith

1987-08-01T23:59:59.000Z

362

A Comparison of Infrared Light Emitting Diodes (IR-LED) versus Infrared  

E-Print Network (OSTI)

B. Characteristics of a typical IR LED analogous to the typeLight Emitting Diodes (IR-LED) versus Infrared Helium-Neon (light emitting diode (IR-LED) to quantitatively measure fuel

Girard, James W.; Bogin, Gregory E; Mack, John Hunter; Chen, J-Y; Dibble, Rober W

2005-01-01T23:59:59.000Z

363

US-LHC IR magnet error analysis and compensation  

SciTech Connect

This paper studies the impact of the insertion-region (IR) magnet field errors on LHC collision performance. Compensation schemes including magnet orientation optimization, body-end compensation, tuning shims, and local nonlinear correction are shown to be highly effective.

Wei, J.; Ptitsin, V.; Pilat, F.; Tepikian, S. [Brookhaven National Lab., Upton, NY (United States); Gelfand, N.; Wan, W.; Holt, J. [Fermi National Accelerator Lab., Batavia, IL (United States)

1998-08-01T23:59:59.000Z

364

Ir-based alloys for ultra-high temperature applications ...  

Site Map; Printable Version; Share this resource. Send a link to Ir-based alloys for ultra-high temperature applications - Energy Innovation Portalto someone by E-mail

365

Synthetic IR Scene Simulation of Air-borne Targets  

E-Print Network (OSTI)

IR scenes of high fidelity are needed to support the development and testing of various target detection and tracking techniques. It is impractical to test detection and tracking algorithms under all conceivable conditions. Therefore, to test the effectiveness of detection and tracking algorithms under variety of scenarios, synthetic IR scenes are generated. For air-borne targets, the presence of clouds plays an important role, since they affect most IR sensors. We propose, a mod- ification of original Gardner's Method [3], in order to generate clouds of richer spectral content. We also ex- plore an algorithm based on self-similarity [5] for cloud texture generation. Synthetic IR cloud images generated by our scene simulation software are radiometrically accurate and have typical cloud texture variations. We use Modtran J.O for radiometric calculation and VRML (Virtual Reality Modeling Language) for scene rendering.

Shankar T. More; Avinash A. Pandit; Avinash A. P; S. N. Merchant; U. B. Desai

2002-01-01T23:59:59.000Z

366

IRS Announces New Tribal Economic Development Bond Allocation...  

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

2012 - 3:46pm Addthis To promote economic growth in tribal communities, Treasury and the Internal Revenue Service (IRS) published new guidance on July 18, 2012, allocating Tribal...

367

Design of high efficiency Mid IR QCL lasers  

E-Print Network (OSTI)

The proposed research is a study of designing high-efficiency Mid-IR quantum cascade lasers (QCL). This thesis explores "injector-less" designs for achieving lower voltage defects and improving wall plug efficiencies through ...

Hsu, Allen Long

2008-01-01T23:59:59.000Z

368

IRS Announces New Tribal Economic Development Bond Allocation Guidance |  

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

IRS Announces New Tribal Economic Development Bond Allocation IRS Announces New Tribal Economic Development Bond Allocation Guidance IRS Announces New Tribal Economic Development Bond Allocation Guidance July 18, 2012 - 3:46pm Addthis To promote economic growth in tribal communities, Treasury and the Internal Revenue Service (IRS) published new guidance on July 18, 2012, allocating Tribal Economic Development Bonds (TEDBs). The TEDB program was established under the American Reinvestment and Recovery Act, and provides Tribes with the authority to issue tax-exempt debt for a wider range of activities to spur job creation and promote economic growth in Indian country. Providing Tribes with the ability to issue tax-exempt debt for a broader scope of activities similar to that available to states and local governments lowers

369

New developments in IR surface vibrational spectroscopy  

DOE Green Energy (OSTI)

Low frequency dynamics at surfaces, particularly in the region of the adsorbate-substrate vibrational modes is of fundamental importance in areas as varied as sliding friction, catalysis, corrosion and epitaxial growth. This paper reviews the new developments in low frequency Infrared Reflection Absorption Spectroscopy using synchrotron radiation as the source. Absolute changes induced in the far infrared for several adsorbate systems on Cu, including CO and H, are dominated by broadband reflectance changes and dipole forbidden vibrational modes which in some cases are an order of magnitude stronger than the dipole allowed modes. The experimental data can be explained by a theory developed by Persson, in which the dielectric response of the substrate is seen as playing a crucial role in the dynamics. In particular the relationships between the wavelength of the light, the penetration depth and the electron mean-free path, are critical.

Hirschmugl, C.J.; Lamont, C.L.A.; Williams, G.P. [Brookhaven National Lab., Upton, NY (United States). National Synchrotron Light Source

1995-12-31T23:59:59.000Z

370

Chemi-Ionization in Neon Plasma: For the Journal of Applied Physics  

Science Conference Proceedings (OSTI)

Rare gas discharges, traditionally considered poor candidates for lighting, have recently been the subject of renewed interest. For example, neon lamps are used for some automobile applications, in which the red visible lines may be used directly for stop signals, or combined with radiation converted from the VUV by a green phosphor to provide an amber light for other traffic signals. In certain discharge regimes, values of rate coefficients of chemi-ionization processes -- those processes involving coll...

2003-02-24T23:59:59.000Z

371

Non-Equilibrium Ionization States of GRB Environments  

E-Print Network (OSTI)

Iron spectral features are thought to be the best tracer of a progenitor of gamma-ray bursts (GRBs). The detections of spectral features such as an iron line and/or a Radiative Recombination edge and Continuum (RRC) were reported in four X-ray afterglows of GRBs. However their properties were different each other burst by burst. For example, Chandra observation of GRB 991216 reported both the strong H-like iron line together with its RRC. On the contrary, Yoshida et al. (2001) report only a detection of the strong RRC in GRB 970828 with ASCA. Since it is difficult to produce the strong RRC, we have to consider special condition for the line and/or the RRC forming region. In this paper, we point out a possibility of a ``non-equilibrium ionization state'' for the line and the RRC forming region.

Yonetoku, D; Masai, K; Yoshida, A; Kawai, N; Namiki, M

2001-01-01T23:59:59.000Z

372

Non-Equilibrium Ionization States of GRB Environments  

E-Print Network (OSTI)

Iron spectral features are thought to be the best tracer of a progenitor of gamma-ray bursts (GRBs). The detections of spectral features such as an iron line and/or a Radiative Recombination edge and Continuum (RRC) were reported in four X-ray afterglows of GRBs. However their properties were different each other burst by burst. For example, Chandra observation of GRB 991216 reported both the strong H-like iron line together with its RRC. On the contrary, Yoshida et al. (2001) report only a detection of the strong RRC in GRB 970828 with ASCA. Since it is difficult to produce the strong RRC, we have to consider special condition for the line and/or the RRC forming region. In this paper, we point out a possibility of a ``non-equilibrium ionization state'' for the line and the RRC forming region.

D. Yonetoku; T. Murakami; K. Masai; A. Yoshida; N. Kawai; M. Namiki

2001-07-18T23:59:59.000Z

373

Liquid chromatography/Fourier transform IR spectrometry interface flow cell  

DOE Patents (OSTI)

A zero dead volume (ZDV) microbore high performance liquid chromatography (.mu.HPLC)/Fourier transform infrared (FTIR) interface flow cell includes an IR transparent crystal having a small diameter bore therein through which a sample liquid is passed. The interface flow cell further includes a metal holder in combination with a pair of inner, compressible seals for directly coupling the thus configured spectrometric flow cell to the outlet of a .mu.HPLC column end fitting to minimize the transfer volume of the effluents exiting the .mu.HPLC column which exhibit excellent flow characteristics due to the essentially unencumbered, open-flow design. The IR beam passes transverse to the sample flow through the circular bore within the IR transparent crystal, which is preferably comprised of potassium bromide (KBr) or calcium fluoride (CaF.sub.2), so as to minimize interference patterns and vignetting encountered in conventional parallel-plate IR cells. The long IR beam pathlength and lensing effect of the circular cross-section of the sample volume in combination with the refractive index differences between the solvent and the transparent crystal serve to focus the IR beam in enhancing sample detection sensitivity by an order of magnitude.

Johnson, Charles C. (Fairfield, OH); Taylor, Larry T. (Blacksburg, VA)

1986-01-01T23:59:59.000Z

374

Liquid chromatography/Fourier transform IR spectrometry interface flow cell  

DOE Patents (OSTI)

A zero dead volume (ZDV) microbore high performance liquid chromatography (..mu.. HPLC)/Fourier transform infrared (FTIR) interface flow cell includes an IR transparent crystal having a small diameter bore therein through which a sample liquid is passed. The interface flow cell further includes a metal holder in combination with a pair of inner, compressible seals for directly coupling the thus configured spectrometric flow cell to the outlet of a ..mu.. HPLC column end fitting to minimize the transfer volume of the effluents exiting the ..mu.. HPLC column which exhibit excellent flow characteristics due to the essentially unencumbered, open-flow design. The IR beam passes transverse to the sample flow through the circular bore within the IR transparent crystal, which is preferably comprised of potassium bromide (KBr) or calcium fluoride (CaF/sub 2/), so as to minimize interference patterns and vignetting encountered in conventional parallel-plate IR cells. The long IR beam pathlength and lensing effect of the circular cross-section of the sample volume in combination with the refractive index differences between the solvent and the transparent crystal serve to focus the IR beam in enhancing sample detection sensitivity by an order of magnitude.

Johnson, C.C.; Taylor, L.T.

1985-01-04T23:59:59.000Z

375

Infrared Radiation Filament And Metnod Of Manufacture  

SciTech Connect

An improved IR radiation source is provided by the invention. A radiation filament has a textured surface produced by seeded ion bombardment of a metal foil which is cut to a serpentine shape and mounted in a windowed housing. Specific ion bombardment texturing techniques tune the surface to maximize emissions in the desired wavelength range and to limit emissions outside that narrow range, particularly at longer wavelengths. A combination of filament surface texture, thickness, material, shape and power circuit feedback control produce wavelength controlled and efficient radiation at much lower power requirements than devices of the prior art.

Johnson, Edward A. (Bedford, MA)

1998-11-17T23:59:59.000Z

376

Ve?jo geleinkeliais civilin? atsakomyb? pagal CITIF CIM taisykles ir SMGS susitarim?, panaumai ir skirtumai.  

E-Print Network (OSTI)

??COTIF CIM ir SMGS reglamentuoja tarptautin? krovini? veim? geleinkeliais tarp valstybi? nari?, kurios yra i? susitarim? alys nar?s. Kadangi abu teis?s aktai danai koreliuoja, kai (more)

Suinskait?,; Nast?

2009-01-01T23:59:59.000Z

377

Large-Area Plasma-Panel Radiation Detectors for Nuclear Medicine Imaging to Homeland Security and the Super Large Hadron Collider  

E-Print Network (OSTI)

A new radiation sensor derived from plasma panel display technology is introduced. It has the capability to detect ionizing and non-ionizing radiation over a wide energy range and the potential for use in many applications. The principle of operation is described and some early results presented.

Friedman, Peter S; Chapman, J Wehrley; Levin, Daniel S; Weaverdyck, Curtis; Zhou, Bing; Benhammou, Yan; Etzion, Erez; Moshe, M Ben; Silver, Yiftah; Beene, James R; Varner, Robert L

2010-01-01T23:59:59.000Z

378

Large-Area Plasma-Panel Radiation Detectors for Nuclear Medicine Imaging to Homeland Security and the Super Large Hadron Collider  

E-Print Network (OSTI)

A new radiation sensor derived from plasma panel display technology is introduced. It has the capability to detect ionizing and non-ionizing radiation over a wide energy range and the potential for use in many applications. The principle of operation is described and some early results presented.

Peter S. Friedman; Robert Ball; J. Wehrley Chapman; Daniel S. Levin; Curtis Weaverdyck; Bing Zhou; Yan Benhammou; Erez Etzion; M. Ben Moshe; Yiftah Silver; James R. Beene; Robert L. Varner Jr.

2010-07-03T23:59:59.000Z

379

A PORTABLE DOSE RATE INSTRUMENT FOR MEASUREMENT OF NATURAL BACK-GROUND RADIATION LEVELS  

SciTech Connect

An instrument of the ionization chamber type which is capable of measuring radiation dose rates down to and below those encountered in natural background was designed and constructed. It consists of a 40-liter ionization chamber coupled to a portable battery-powered electrometer. The chamber polarizing battery is a part of the chamber center electrode assembly and is located inside the chamber. (auth)

Rising, F.L.

1960-12-19T23:59:59.000Z

380

Optical Radiation  

Science Conference Proceedings (OSTI)

*. Bookmark and Share. Optical Radiation Measurements. Fees for services are located directly below the technical contacts ...

2013-04-09T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

Tunable and collimated terahertz radiation generation by femtosecond laser pulses  

Science Conference Proceedings (OSTI)

A mechanism is proposed for the generation of tunable terahertz (THz) radiation under the application of two femtosecond laser pulses and an external magnetic field, where quick tunnel ionization is achieved that leads to higher plasma density evolution and large residual current for the efficient THz radiation generation. With the optimization of magnetic field, phase difference, and amplitudes of lasers' fields, a THz source can be obtained with tunable frequency and power along with a control on the direction of radiation emission.

Malik, Hitendra K.; Malik, Anil K.

2011-12-19T23:59:59.000Z

382

Grid-based methods for diatomic quantum scattering problems II: Time-dependent treatment of single- and two-photon ionization of H2+  

SciTech Connect

The time-dependent Schr\\"odinger equation for H2+ in a time-varying electromagnetic field is solved in the fixed-nuclei approximation using a previously developed finite-element/ discrete variable representation in prolate spheroidal coordinates. Amplitudes for single- and two-photon ionization are obtained using the method of exterior complex scaling to effectively propagate the field-free solutions from the end of the radiation pulse to infinite times. Cross sections are presented for one-and two-photon ionization for both parallel and perpendicular polarization of the photon field, as well as photoelectron angular distributions for two-photon ionization.

Rescigno, Thomas N.; Tao, L.; McCurdy, C.W.

2009-04-20T23:59:59.000Z

383

Unexpected photoreactivation of Vibrio harveyi bacteria living in ionization environment  

SciTech Connect

Bacteria undergoing environmental effects is extremely interesting for structural, mechanistic, and evolutionary implications. Luminescent bacteria that have evolved in a specific ambient have developed particular responses and their behavior can give us new suggestions on the task and production of luciferina proteins. To analyze the UV interaction under controlled laboratory conditions, we used photoluminescent bacterial strains belonging to a new species evolutionarily close to Vibrio harveyi sampled from a coastal cave with a high radon content that generates ionizing radiation. The survival of the bacterial strains was analyzed, in the light and in the dark, following a variety of genotoxic treatments including UV radiation exposure. The strains were irradiated by a germicide lamp. The results demonstrated that most of the strains exhibited a low rate of survival after the UV exposure. After irradiation by visible light following the UV exposure, all strains showed a high capability of photoreactivation when grown. This capability was quite unexpected because these bacteria were sampled from a dark ambient without UV radiation. This leads us to hypothesize that the photoreactivation in these bacteria might have been evolved to repair DNA lesions also induced by different radiation sources other than UV (e.g., x-ray) and that the luminescent bacteria might use their own light emission to carry out the photoreactivation. The high capability of photoreactivation of these bacteria was also justified by the results of deconvolution. The deconvolution was applied to the emission spectra and it was able to show evidence of different light peaks. The presence of the visible peak could control the photolysis enzyme.

Alifano, P.; Tala, A.; Tredici, S. M. [Dipartimento Microbiologia, Di.S.Te.B.A., Universita del Salento, via Provinciale Lecce-Monteroni, C.P. 193, 73100 Lecce (Italy); Nassisi, V. [Laboratorio di Elettronica Applicata e Strumentazione, LEAS, Dipartimento di Fisica, Universita del Salento and INFN-Lecce, Via Provinciale Lecce-Monteroni, 73100 Lecce (Italy); Siciliano, M. V. [Laboratorio di Elettronica Applicata e Strumentazione, LEAS, Dipartimento di Fisica, Universita del Salento and INFN-Lecce, Via Provinciale Lecce-Monteroni, 73100 Lecce (Italy); Dipartimento di Scienza dei Materiali, University of Salento, via Provinciale Lecce- Monteroni, C.P. 193, 73100 Lecce (Italy)

2011-05-15T23:59:59.000Z

384

MUCOOL: Ionization Cooling R&D  

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

Laboratory Laboratory MUCOOL Muon Ionization Cooling R&D Welcome to the muon ionization cooling experimental R&D page. The MuCool collaboration has been formed to pursue the development of a muon ionization cooling channel for a high luminosity muon collider. For more information please contact Alan Bross (Spokesperson: bross@fnal.gov), Rick Fernow (BNL Contact person: fernow1@bnl.gov), or Mike Zisman (LBNL Contact person: mszisman@lbl.gov). General MUCOOL Telephone Book MUCOOL Notes MUCOOL Collaborating Institutes and Interests Useful Links Link to IIT MUCOOL page Meetings Muon Collaboration Friday Meetings Fermilab Muon Group Monday Meetings MTA RF Workshop (August 22, 2007 - Fermilab) Low Emittance Muon Collider Workshop (February 12-16, 2007, Fermilab) Low Emittance Muon Collider Workshop (February 6-10, 2006, Fermilab)

385

Ionization-chamber smoke detector system  

DOE Patents (OSTI)

This invention relates to an improved smoke-detection system of the ionization-chamber type. In the preferred embodiment, the system utilizes a conventional detector head comprising a measuring ionization chamber, a reference ionization chamber, and a normally non-conductive gas triode for discharging when a threshold concentration of airborne particulates is present in the measuring chamber. The improved system is designed to reduce false alarms caused by fluctuations in ambient temperature. Means are provided for periodically firing the gas discharge triode and each time recording the triggering voltage required. A computer compares each triggering voltage with its predecessor. The computer is programmed to energize an alarm if the difference between the two compared voltages is a relatively large value indicative of particulates in the measuring chamber and to disregard smaller differences typically resulting from changes in ambient temperature.

Roe, Robert F. (Jackson, OH)

1976-10-19T23:59:59.000Z

386

Advances Toward Inner-Shell Photo-Ionization X-Ray Lasing at 45 (Angstrom)  

Science Conference Proceedings (OSTI)

The inner-shell photo-ionization (ISPI) scheme requires photon energies at least high enough to photo-ionize the K-shell. {approx}286 eV, in the case of carbon. As a consequence of the higher cross-section, the inner-shell are selectively knocked out, leaving a hole state 1s2s{sup 2}2p{sup 2} in the singly charged carbon ion. This generates a population inversion to the radiatively connected state 1s{sup 2}2s{sup 2}2p in C+, leading to gain on the 1s-2p transition at 45 {angstrom}. The resonant character of the lasing transition in the single ionization state intrinsically allows much higher quantum efficiency compared to other schemes. Competing processes that deplete the population inversion include auto-ionization, Auger decay, and in particular collisional ionization of the outer-shell electrons by electrons generated during photo-ionization. These competing processes rapidly quench the gain. Consequently, the pump method must be capable of populating the inversion at a rate faster than the competing processes. This can be achieved by an ultra-fast, high intensity laser that is able to generate an ultra-fast, bright x-ray source. With current advances in the development of high-power, ultra-short pulse lasers it is possible to realize fast x-ray sources based that can deliver powerful pulses of light in the multiple hundred terawatt regime and beyond. They will discuss in greater detail concept, target design and a series of x-ray spectroscopy investigations they have conducted in order to optimize the absorber/x-ray converter--filter package.

Moon, S J; Weber, F A; Celliers, P M; Eder, D C

2002-07-18T23:59:59.000Z

387

KUB5/HERA: a dual acting protein that suppresses genomic instability and promotes DNA repair after low dose IR exposure  

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

KUB5/HERA: a dual acting protein that suppresses genomic instability and KUB5/HERA: a dual acting protein that suppresses genomic instability and promotes DNA repair after low dose IR exposure Julio C. Morales 1 , Amy Rommel 1 , Konstantin Leskov 2 , Walter M. Hittelman 3 , David A. Boothman 1# 1 Simmons Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA. 2 Department of Radiation Oncology, Case Western Reserve University, Cleveland, OH 44106, USA. 3 Department of Experimental Therapeutics, M.D. Anderson Cancer Center, Houston, TX 77030, USA. # To whom correspondence should be addressed. E-mail: David.Boothman@utsouthwestern.edu Eukaryotic cells can respond to DNA double strand breaks created by low doses of IR by activating homologous recombination (HR) or non-homologous end- joining (NHEJ) pathways to repair DNA. A yeast two-hybrid screen using Ku70 as

388

About Radiation  

NLE Websites -- All DOE Office Websites (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.

389

WATER ICE IN HIGH MASS-LOSS RATE OH/IR STARS  

SciTech Connect

We investigate water-ice features in spectral energy distributions (SEDs) of high mass-loss rate OH/IR stars. We use a radiative transfer code which can consider multiple components of dust shells to make model calculations for various dust species including water ice in the OH/IR stars. We find that the model SEDs are sensitively dependent on the location of the water-ice dust shell. For two sample stars (OH 127.8+0.0 and OH 26.5+0.6), we compare the detailed model results with the infrared observational data including the spectral data from the Infrared Space Observatory (ISO). For the two sample stars, we reproduce the crystalline water-ice features (absorption at 3.1 {mu}m and 11.5 {mu}m; emission at 44 and 62 {mu}m) observed by ISO using a separate component of the water-ice dust shell that condensed at about 84-87 K (r {approx} 1500-1800 AU) as well as the silicate dust shell that condensed at about 1000 K (r {approx} 19-25 AU). For a sample of 1533 OH/IR stars, we present infrared two-color diagrams (2CDs) using the Infrared Astronomical Satellite and AKARI data compared with theoretical model results. We find that the theoretical models clearly show the effects of the crystalline water-ice features (absorption at 11.5 {mu}m and emission at 62 {mu}m) on the 2CDs.

Suh, Kyung-Won; Kwon, Young-Joo, E-mail: kwsuh@chungbuk.ac.kr [Department of Astronomy and Space Science, Chungbuk National University, Cheongju-City 361-763 (Korea, Republic of)] [Department of Astronomy and Space Science, Chungbuk National University, Cheongju-City 361-763 (Korea, Republic of)

2013-01-10T23:59:59.000Z

390

Mapping Neutral Hydrogen During Reionization with the Ly-alpha Emission from Quasar Ionization Fronts  

E-Print Network (OSTI)

We present a new method to directly map the neutral-hydrogen distribution during the reionization epoch and to constrain the emission properties of the highest-redshift quasars (QSOs). As a tracer of HI, we propose to use the Ly-alpha radiation produced by quasar ionization fronts (I-fronts) that expand in the partially ionized intergalactic medium (IGM) before reionization is complete. These Ly-alpha photons are mainly generated by collisional excitations of hydrogen atoms in the boundary of the rapidly expanding HII region. The observable signal is produced by the part of the I-front that lies behind the QSO with respect to the observer. Combining two radiative transfer models (one for the QSO ionizing radiation and one for the Ly-alpha photons), we estimate the expected Ly-alpha spectral shape and surface brightness (SB) for a large number of configurations where we varied both the properties of the ionizing QSO and of the surrounding medium. We find that the expected signal is observable as a single (broad) emission line with a characteristic width of 100-200 km/s. The expected SB produced at redshift z~6.5 within a fully neutral region (at mean density) by a typical QSO I-front lies in the range $10^{-21}-10^{-20}$ erg s$^{-1}$ cm$^{-2}$ arcsec$^{-2}$ and decreases proportionally to $(1+z)^2$ for a given QSO age. QSOs with harder spectra may produce a significantly brighter emission at early phases. The signal may cover up to a few hundred square arcmin on the sky and should be already detectable with current facilities by means of moderate/high resolution spectroscopy. The detection of this Ly-alpha emission can shed new light on the reionization history, the age and the emission properties of the highest-redshift QSOs. (abridged)

Sebastiano Cantalupo; Cristiano Porciani; Simon J. Lilly

2007-09-05T23:59:59.000Z

391

Low Dose Radiation Research Program: Genetic Factors Affecting  

NLE Websites -- All DOE Office Websites (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

392

Radiation Physics Portal  

Science Conference Proceedings (OSTI)

NIST Home > Radiation Physics Portal. Radiation Physics Portal. ... more. >> see all Radiation Physics programs and projects ... ...

2013-08-08T23:59:59.000Z

393

Analytical models for total dose ionization effects in MOS devices.  

DOE Green Energy (OSTI)

MOS devices are susceptible to damage by ionizing radiation due to charge buildup in gate, field and SOI buried oxides. Under positive bias holes created in the gate oxide will transport to the Si / SiO{sub 2} interface creating oxide-trapped charge. As a result of hole transport and trapping, hydrogen is liberated in the oxide which can create interface-trapped charge. The trapped charge will affect the threshold voltage and degrade the channel mobility. Neutralization of oxidetrapped charge by electron tunneling from the silicon and by thermal emission can take place over long periods of time. Neutralization of interface-trapped charge is not observed at room temperature. Analytical models are developed that account for the principal effects of total dose in MOS devices under different gate bias. The intent is to obtain closed-form solutions that can be used in circuit simulation. Expressions are derived for the aging effects of very low dose rate radiation over long time periods.

Campbell, Phillip Montgomery; Bogdan, Carolyn W.

2008-08-01T23:59:59.000Z

394

ARM - Field Campaign - IR Cloud Camera Feasibility Study  

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

govCampaignsIR Cloud Camera Feasibility Study govCampaignsIR Cloud Camera Feasibility Study Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : IR Cloud Camera Feasibility Study 2010.12.06 - 2010.12.13 Lead Scientist : Kyle Leesman For data sets, see below. Description During December 2010, a prototype LWIR cloud camera system was deployed at the Southern Great Plains Guest Instrument Facility (SGP-GIF). The system consisted of a microbolometer camera (~7-15 ìm) to capture sky imagery, a blackbody calibration source, and a GPS receiver used to estimate atmospheric column water vapor and constrain atmospheric compensation. The camera system collected calibrated sky radiance images co-incident with the SGP Central Facility with the goal of quantitatively assessing its ability

395

Supermassive Black Holes and the Warm Ionized  

E-Print Network (OSTI)

Supermassive Black Holes and the Warm Ionized Gas in Early-type Galaxies Renbin Yan University stars actively. (late-type galaxies) #12;Prevalence of Supermassive Black Holes in Massive Galaxies MBH merging Right after coalescing Post-merger Star Formation Rate Black Hole Accretion Rate #12;Maintenance

Wang, Ming-Jye

396

Radiation Cataract  

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

radiation including patients undergoing diagnostic CT scans or radiotherapy, atomic bomb survivors, residents of radioactively contaminated buildings, victims of the...

397

Radiation-tolerant imaging device  

DOE Patents (OSTI)

A barrier at a uniform depth for an entire wafer is used to produce imaging devices less susceptible to noise pulses produced by the passage of ionizing radiation. The barrier prevents charge created in the bulk silicon of a CCD detector or a semiconductor logic or memory device from entering the collection volume of each pixel in the imaging device. The charge barrier is a physical barrier, a potential barrier, or a combination of both. The physical barrier is formed by an SiO.sub.2 insulator. The potential barrier is formed by increasing the concentration of majority carriers (holes) to combine with the electron's generated by the ionizing radiation. A manufacturer of CCD imaging devices can produce radiation-tolerant devices by merely changing the wafer type fed into his process stream from a standard wafer to one possessing a barrier beneath its surface, thus introducing a very small added cost to his production cost. An effective barrier type is an SiO.sub.2 layer.

Colella, Nicholas J. (Livermore, CA); Kimbrough, Joseph R. (Pleasanton, CA)

1996-01-01T23:59:59.000Z

398

Development of an XUV-IR free-electron laser user facility for scientific research and industrial applications  

Science Conference Proceedings (OSTI)

Los Alamos has designed and proposes to establish an XUV-IR free- electron laser (FEL) user facility for scientific research and industrial applications based on coherent radiation ranging from soft x-rays as short as 1 nm to far-infrared wavelengths as long as 100 {mu}m. As the next-generation light source beyond low-emittance storage rings with undulator insertion devices, this proposed national FEL user facility should make available to researchers broadly tunable, picosecond-pulse, coherent radiation with 10{sup 4} to 10{sup 7} greater spectral flux and brightness. The facility design is based on two series of FEL oscillators including one regenerative amplifier. The primary series of seven FEL oscillators, driven by a single, 1-GeV rf linac, spans the short-wavelength range from 1 to 600 nm. A second 60-MeV rf linac, synchronized with the first, drives a series of three Vis/IR FEL oscillators to cover the 0. 5 to 100-{mu}m range. This paper presents the motivation for such a facility arising from its inherently high power per unit bandwidth and its potential use for an array of scientific and industrial applications, describes the facility design, output parameters, and user laboratories, makes comparisons with synchrotron radiation sources, and summarizes recent technical progress that supports the technical feasibility. 80 refs., 9 figs., 6 tabs.

Newnam, B.E.; Warren, R.W.; Conradson, S.D.; Goldstein, J.C.; McVey, B.D.; Schmitt, M.J.; Elliott, C.J.; Burns, M.J.; Carlsten, B.E.; Chan, K.C.; Johnson, W.J.; Wang, T.S.; Sheffield, R.L.; Meier, K.L.; Olsher, R.H.; Scott, M.L.; Griggs, J.E.

1991-01-01T23:59:59.000Z

399

Electron Ionization Library Component of the NIST/EPA/NIH ...  

Science Conference Proceedings (OSTI)

Electron Ionization Library Component of the NIST/EPA/NIH Mass Spectral Library and NIST GC Retention Index Database. Summary: ...

2013-07-10T23:59:59.000Z

400

Probe measurements of the ionization of air behind strong shocks  

SciTech Connect

Detailed measurements of the ionization of air behind strong shocks over a broad range of shocks velocities are reported. (AIP)

Gorelov, V.A.; Kil' dyushova, L.A.

1981-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" from the National Library of EnergyBeta (NLEBeta).
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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

MID-IR FORCAST/SOFIA OBSERVATIONS OF M82  

SciTech Connect

We present 75'' Multiplication-Sign 75'' size maps of M82 at 6.4 {mu}m, 6.6 {mu}m, 7.7 {mu}m, 31.5 {mu}m, and 37.1 {mu}m with a resolution of {approx}4'' that we have obtained with the mid-IR camera FORCAST on SOFIA. We find strong emission from the inner 60'' ({approx}1 kpc) along the major axis, with the main peak 5'' west-southwest of the nucleus and a secondary peak 4'' east-northeast of the nucleus. The detailed morphology of the emission differs among the bands, which is likely due to different dust components dominating the continuum emission at short mid-IR wavelengths and long mid-IR wavelengths. We include Spitzer-IRS and Herschel/PACS 70 {mu}m data to fit spectral energy distribution templates at both emission peaks. The best-fitting templates have extinctions of A{sub V} = 18 and A{sub V} = 9 toward the main and secondary emission peak and we estimated a color temperature of 68 K at both peaks from the 31 {mu}m and 37 {mu}m measurement. At the emission peaks the estimated dust masses are on the order of 10{sup 4} M{sub Sun }.

Nikola, T.; Herter, T. L.; Adams, J. D.; Gull, G. E.; Henderson, C. P.; Schoenwald, J.; Stacey, G. [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States); Vacca, W. D.; De Buizer, J. M. [Universities Space Research Association, NASA Ames Research Center, MS 211-3, Moffett Field, CA 94035 (United States); Keller, L. D. [Department of Physics, Ithaca College, Ithaca, NY 14850 (United States); Morris, M. R. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1547 (United States); Tielens, A. [Leiden Observatory, P.O. Box 9513, Leiden, 2300 RA (Netherlands)

2012-04-20T23:59:59.000Z

402

Benchmark Measurements of the Ionization Balance of Non-LTE Gold  

SciTech Connect

The authors present a series of benchmark measurements of the ionization balance of well characterized gold plasmas with and without external radiation fields at electron densities near 10{sup 21} cm{sup -3} and various electron temperatures spanning the range 0.8 to 2.4 keV. They have analyzed time- and space-resolved M-shell gold emission spectra using a sophisticated collisional-radiative model with hybrid level structure, finding average ion changes ranging from 42 to 50. At the lower temperatures, the spectra exhibit significant sensitivity to external radiation fields and include emission features from complex N-shell ions not previously studied at these densities. The measured spectra and inferred provide a stringent test for non-local thermodynamic equilibrium (non-LTE) models of complex high-Z ions.

Heeter, R F; Hansen, S B; Fournier, K B; Foord, M E; Froula, D H; Mackinnon, A J; May, M J; Schneider, M B; Young, B F

2007-04-20T23:59:59.000Z

403

Time damping of non-adiabatic magnetohydrodynamic waves in a partially ionized prominence plasma: Effect of helium  

E-Print Network (OSTI)

Prominences are partially ionized, magnetized plasmas embedded in the solar corona. Damped oscillations and propagating waves are commonly observed. These oscillations have been interpreted in terms of magnetohydrodynamic (MHD) waves. Ion-neutral collisions and non-adiabatic effects (radiation losses and thermal conduction) have been proposed as damping mechanisms. We study the effect of the presence of helium on the time damping of non-adiabatic MHD waves in a plasma composed by electrons, protons, neutral hydrogen, neutral helium (He I), and singly ionized helium (He II) in the single-fluid approximation. The dispersion relation of linear non-adiabatic MHD waves in a homogeneous, unbounded, and partially ionized prominence medium is derived. The period and the damping time of Alfven, slow, fast, and thermal waves are computed. A parametric study of the ratio of the damping time to the period with respect to the helium abundance is performed. The efficiency of ion-neutral collisions as well as thermal conduc...

Soler, R; Ballester, J L

2009-01-01T23:59:59.000Z

404

Co-Regulation among genes and pathways that are responsive to low-dose ionizing  

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

Regulation among genes and pathways that are responsive to low-dose ionizing Regulation among genes and pathways that are responsive to low-dose ionizing radiation. Matthew A. Coleman 1 , Anya Krefft 1 , Francesca Pearson 1 , Leif E. Peterson 2 , Jian Jian Li 3 , Xiaowen Xin 1 , Terrence Critchlow 1 , Ilkay Altintas 4 , Bertram Ludaescher 5 and Andrew J. Wyrobek 6 . 1 Biosciences, LLNL, Livermore, CA, 94550, 2 Departments of Molecular and Human Genetics and Medicine, Baylor College of Medicine, Houston, TX, 77030, 3 School of Health Sciences, Purdue University, West Lafayette, IN, 47907. 4 San Diego Supercomputer Center, University of California, San Diego La Jolla, CA 92093. 5 Department of Computer Science, University of California, Davis, CA 95616. 6 Life Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA. 94706. Contact information: coleman16@llnl.gov

405

The Relationship between the Planetary and Surface Net Radiation  

Science Conference Proceedings (OSTI)

In this study, an attempt has been made to derive the daily net radiation at the top of the atmosphere using the Geostationary Operational Environmental Satellite (GOES) visible (0.550.75 ?m) and IR window (10.512.5 ?m) observations and to ...

R. T. Pinker; J. A. Ewing; J. D. Tarpley

1985-11-01T23:59:59.000Z

406

Radiation Information  

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

Radiation Information << Timeline >> Content on this page requires a newer version of Adobe Flash Player. Get Adobe Flash player July 31, 1942 The Army Corp of Engineers leases...

407

SPITZER CHARACTERIZATION OF DUST IN THE IONIZED MEDIUM OF THE LARGE MAGELLANIC CLOUD  

SciTech Connect

A systematic investigation of dust emission associated with ionized gas has so far been performed only in our Galaxy and for wavelengths longer than 60 {mu}m. Newly available Spitzer data now offer the opportunity to carry out a similar analysis in the Large Magellanic Cloud (LMC). By cross-correlating Spitzer Surveying the Agents of a Galaxy's Evolution (SAGE) data with the Australia Telescope Compact Array/Parkes H I 21 cm data, the NANTEN {sup 12}CO (J = 1-0) data, and both the Southern H-Alpha Sky Survey Atlas H{alpha} and the Parkes 6 cm data, we investigate the physical properties of dust associated with the different phases of the gas (atomic, molecular, and ionized). In particular, we study the presence and nature of dust from 3.6 to 160 {mu}m and for various regimes of ionized gas, spanning emission measures from {approx}1 pc cm{sup -6} (diffuse component) to {approx}10{sup 3}pc cm{sup -6} (H II regions). Using a dust emission model and testing our results with several radiation field spectra, we show that dust in ionized gas is warmer than dust associated with other phases (atomic and molecular). We also find a decrease of the polycyclic aromatic hydrocarbon (PAH) relative abundance with respect to big grains, as well as an increase of the near-infrared (NIR) continuum. These three results (i.e., warmer temperature, decrease of PAH abundance, and increase of the NIR continuum) are found consistently for all regimes of ionized gas. On the contrary, the molecular phase appears to provide favorable conditions for the survival of PAHs. Furthermore, the very small grain relative abundance tends to increase in the ionized phase, especially in bright H II regions. Last but not least, our analysis shows that the emissivity of dust associated with ionized gas is lower in the LMC than in our Galaxy and that this difference is not accounted for by the lower metallicity of the LMC.

Paradis, Deborah; Paladini, Roberta; Noriega-Crespo, Alberto [Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); Lagache, Guilaine [Institut d'Astrophysique Spatiale, 91405 Orsay (France); Kawamura, Akiko; Fukui, Yasuo [Department of Astrophysics, Nagoya University, Chikusa-ku, Nagoya 464-8602 (Japan); Onishi, Toshikazu [Department of Physical Science, Osaka Prefecture University, Gakuen 1-1, Sakai, Osaka 599-8531 (Japan)

2011-07-01T23:59:59.000Z

408

Low Dose Radiation Research Program: Current Funded Project Descriptions  

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

Funded Project Descriptions Funded Project Descriptions Effects Of Low Doses of Radiation on DNA Repair Jointly funded by NASA and DOE Eric J Ackerman Pacific Northwest National Laboratory Richland, WA 99352 Dr. Ackerman will study the effect of low doses of ionizing radiation on the repair of different types of damage to DNA, including damage from ionizing radiation and that produced by the normal internal operation of the cell. Using a very sensitive technique called host cell reactivation assay (HCR), he will quantitatively measure the repair of each type of DNA damage and thereby measure if the cellular repair system itself has been damaged. He will also determine if unique forms of DNA repair system damage are induced by low doses of cosmic radiation exposure present during space

409

Low Dose Radiation Research Program: Project Descriptions-Archive  

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

Project Descriptions-Archive Project Descriptions-Archive Effects Of Low Doses of Radiation on DNA Repair Eric J Ackerman (former PNNL) (Jointly funded by NASA and DOE) Pacific Northwest National Laboratory Richland, WA Dr. Ackerman will study the effect of low doses of ionizing radiation on the repair of different types of damage to DNA, including damage from ionizing radiation and that produced by the normal internal operation of the cell. Using a very sensitive technique called host cell reactivation assay (HCR), he will quantitatively measure the repair of each type of DNA damage and thereby measure if the cellular repair system itself has been damaged. He will also determine if unique forms of DNA repair system damage are induced by low doses of cosmic radiation exposure present during space

410

BNL NASA Space Radiation Laboratory  

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

Purpose: To use beams of heavy ions provided by the Booster accelerator at Brookhaven to study the effects of simulated space radiation on biological and physical systems, with the goal of developing methods and materials to reduce the risk to human beings on prolonged space missions of the effects of ionizing radiation Sponsor: National Aeronautics and Space Administration (NASA) Project cost $34 million over 4 years Operating costs Nearly $8 million per year in 2007 Features * beams of heavy ions extracted from the Booster accelerator with masses and energies similar to the cosmic rays encountered in space: * 1-billion electron volt (GeV)/nucleon iron-56 * 0.3-GeV/nucleon gold-97 * 0.6-GeV/nucleon silicon-28 * 1-GeV/nucleon protons * 1-GeV/nucleon titanium

411

Non-invasive, MRI-compatible fibreoptic device for functional near-IR reflectometry of human brain  

SciTech Connect

A non-invasive device for measuring blood oxygen variations in human brain is designed, implemented, and tested for MRI compatibility. The device is based on principles of near-IR reflectometry; power LEDs serve as sources of probing radiation delivered to patient skin surface through optical fibres. Numerical Monte Carlo simulations of probing radiation propagation in a multilayer brain model are performed to evaluate signal levels at different source - detector separations at three operation wavelengths and an additional wavelength of 915 nm. It is shown that the device can be applied for brain activity studies using power LEDs operating at 830 and 915 nm, while employment of wavelength of 660 nm requires an increased probing power. Employment of the wavelength of 592 nm in the current configuration is unreasonable. (application of lasers and laser-optical methods in life sciences)

Sorvoja, H.S.S.; Myllylae, T S; Myllylae, Risto A [University of Oulu, Optoelectronics and Measurements Techniques Laboratory (Finland); Kirillin, M Yu; Sergeeva, Ekaterina A [Institute of Applied Physics, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation); Elseoud, A A; Nikkinen, J; Tervonen, O; Kiviniemi, V [MRI Research Unit, Department of Diagnostic Radiology, Oulu University Hospital, Oulu (Finland)

2011-01-24T23:59:59.000Z

412

Radiation-hardened microelectronics for accelerators  

Science Conference Proceedings (OSTI)

Ionization and displacement phenomena in semiconducting materials are reviewed. The different classes of radiation discussed include fast neutron, x-rays and gamma rays and heavy charged particles. Both transient and steady state phenomena will be discussed. How these basic effects lead to change in the electrical characteristics of transistors and diodes and the functionality of intergrated circuits are summarized. The fundamental radiation limits for various semiconductor technologies are summarized. Recommendations and precautions are given regarding the applicability of various microelectronic technologies to different accelerator environments. 14 refs., 7 tabs.

Gover, J.E.; Fischer, T.A.

1988-01-01T23:59:59.000Z

413

IR OPTICS MEASUREMENT WITH LINEAR COUPLING'S ACTION-ANGLE PARAMETERIZATION.  

Science Conference Proceedings (OSTI)

A parameterization of linear coupling in action-angle coordinates is convenient for analytical calculations and interpretation of turn-by-turn (TBT) beam position monitor (BPM) data. We demonstrate how to use this parameterization to extract the twiss and coupling parameters in interaction regions (IRs), using BPMs on each side of the long IR drift region. The example of TBT BPM analysis was acquired at the Relativistic Heavy Ion Collider (RHIC), using an AC dipole to excite a single eigenmode. Besides the full treatment, a fast estimate of beta*, the beta function at the interaction point (IP), is provided, along with the phase advance between these BPMs. We also calculate and measure the waist of the beta function and the local optics.

LUO, Y.; BAI, M.; PILAT, R.; SATOGATA, T.; TRBOJEVIC, D.

2005-05-16T23:59:59.000Z

414

Influence of collisions on coherent IR multiphoton absorption in thiophosgene  

Science Conference Proceedings (OSTI)

Absolute changes due to IR pumping in the intergrated rotational population of the vibrationless level (000000) of thiophosgene have been measured under beam conditions and bulb conditions (1--1000 mTorr). Under collisionless conditions, large decreases are observed which reflect depopulation of all rotational states at a single CO/sub 2/ laser frequency. At higher thiophosgene pressure, less depopulation occurs; zero depopulation of the vibrationless level is observed at pressure > or = 300 mTorr within experimental uncertainty (> gas kinetic.

Brenner, D.M.; Spencer, M.; Steinfeld, J.I.

1981-09-15T23:59:59.000Z

415

Sequential circuit design for radiation hardened multiple voltage integrated circuits  

DOE Patents (OSTI)

The present invention includes a radiation hardened sequential circuit, such as a bistable circuit, flip-flop or other suitable design that presents substantial immunity to ionizing radiation while simultaneously maintaining a low operating voltage. In one embodiment, the circuit includes a plurality of logic elements that operate on relatively low voltage, and a master and slave latches each having storage elements that operate on a relatively high voltage.

Clark, Lawrence T. (Phoenix, AZ); McIver, III, John K. (Albuquerque, NM)

2009-11-24T23:59:59.000Z

416

Dust Tracking Using Composite Visible/IR Images: A Case Study  

Science Conference Proceedings (OSTI)

Visible and infrared (IR) images from the National Oceanic and Atmospheric Administration's (NOAA's) Advanced Very High Resolution Radiometer are composited to improve the depiction of airborne dust over coastlines. On IR images, wind-raised dust ...

Thomas F. Lee

1989-06-01T23:59:59.000Z

417

Device for calibrating a radiation detector system  

DOE Patents (OSTI)

A device for testing a radiation detector system that includes at least two arrays of radiation detectors that are movable with respect to each other. The device includes a "shield plate" or shell, and an opposing "source plate" containing a source of ionizing radiation. Guides are attached to the outer surface of the shell for engaging the forward ends of the detectors, thereby reproducibly positioning the detectors with respect to the source and with respect to each other, thereby ensuring that a predetermined portion of the radiation emitted by the source passes through the shell and reaches the detectors. The shell is made of an hydrogenous material having approximately the same radiological attenuation characteristics as composite human tissue. The source represents a human organ such as the lungs, heart, kidneys, heart, liver, spleen, pancreas, thyroid, testes, prostate, or ovaries. The source includes a source of ionizing radiation having a long half-life and an activity that is within the range typically searched for in human subjects.

Mc Fee, Matthew C. (New Ellenton, SC); Kirkham, Tim J. (Beech Island, SC); Johnson, Tippi H. (Aiken, SC)

1994-01-01T23:59:59.000Z

418

Device for calibrating a radiation detector system  

DOE Patents (OSTI)

A device is disclosed for testing a radiation detector system that includes at least two arrays of radiation detectors that are movable with respect to each other. The device includes a ''shield plate'' or shell, and an opposing ''source plate'' containing a source of ionizing radiation. Guides are attached to the outer surface of the shell for engaging the forward ends of the detectors, thereby reproducibly positioning the detectors with respect to the source and with respect to each other, thereby ensuring that a predetermined portion of the radiation emitted by the source passes through the shell and reaches the detectors. The shell is made of an hydrogenous material having approximately the same radiological attenuation characteristics as composite human tissue. The source represents a human organ such as the lungs, heart, kidneys, liver, spleen, pancreas, thyroid, testes, prostate, or ovaries. The source includes a source of ionizing radiation having a long half-life and an activity that is within the range typically searched for in human subjects. 3 figures.

McFee, M.C.; Kirkham, T.J.; Johnson, T.H.

1994-12-27T23:59:59.000Z

419

Low Dose Radiation Research Program: Radiation-Induced Nuclear Factor kB  

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

Radiation-Induced Nuclear Factor kB mediates survival advantage by Radiation-Induced Nuclear Factor kB mediates survival advantage by Telomerase Activation. Authors: Natarajan M.,1 Mohan S.,2 Pandeswara, S.L.,1 and Herman T.S.1 Institutions: Departments of 1Radiation Oncology and 2Pathology, The University of Texas Health Science Center, San Antonio, Texas Activation of NF-kB in response to low doses of ionizing radiation was first shown in our laboratory. Although studies have shown that NF-kB plays an important role in anti-apoptotic function, little has been done to understand the molecular link between the activation of NF-kB and cellular outcome such as enhanced cell survival after low dose low-linear transfer (LET) radiation. Because upregulation of telomerase activity is associated with longevity and allows cells to escape from senescence, we hypothesize

420

Uncooled thin film pyroelectric IR detector with aerogel thermal isolation  

Science Conference Proceedings (OSTI)

Uncooled pyroelectric IR imaging systems, such as night vision goggles, offer important strategic advantages in battlefield scenarios and reconnaissance surveys. Until now, the current technology for fabricating these devices has been limited by low throughput and high cost which ultimately limit the availability of these sensor devices. We have developed and fabricated an alternative design for pyroelectric IR imaging sensors that utilizes a multilayered thin film deposition scheme to create a monolithic thin film imaging element on an active silicon substrate for the first time. This approach combines a thin film pyroelectric imaging element with a thermally insulating SiO{sub 2} aerogel thin film to produce a new type of uncooled IR sensor that offers significantly higher thermal, spatial, and temporal resolutions at a substantially lower cost per unit. This report describes the deposition, characterization and optimization of the aerogel thermal isolation layer and an appropriate pyroelectric imaging element. It also describes the overall integration of these components along with the appropriate planarization, etch stop, adhesion, electrode, and blacking agent thin film layers into a monolithic structure. 19 refs., 8 figs., 6 tabs.

Ruffner, J.A.; Clem, P.G.; Tuttle, B.A. [and others

1998-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

15TH INTERNATIONAL SYMPOSIUM ON TOXICITY ASSESSMENT Alpha radiation exposure decreases apoptotic cells in zebrafish  

E-Print Network (OSTI)

15TH INTERNATIONAL SYMPOSIUM ON TOXICITY ASSESSMENT Alpha radiation exposure decreases apoptotic of an adaptive response by the ionizing radiation against sub- sequent exposures to Cd. Keywords Multiple embryos subjected to a priming exposure provided by one environmental stressor (low-dose alpha particles

Yu, K.N.

422

Regime for a Self-ionizing Raman Laser Amplifier  

DOE Green Energy (OSTI)

Backward Raman amplification and compression at high power might occur if a long pumping laser pulse is passed through a plasma to interact resonantly with a counter-propagating short seed pulse [V.M. Malkin, et al., Phys. Rev. Lett. 82 (1999) 4448-4451]. One critical issue, however, is that the pump may be unacceptably depleted due to spontaneous Raman backscatter from intrinsic fluctuations in the amplifying plasma medium prior to its useful interaction with the seed. Premature backscatter may be avoided, however, by employing a gaseous medium with pump intensities too low to ionize the medium, and using the intense seed to produce the plasma by rapid photoionization as it is being amplified [V.M. Malkin, et al., Phys. Plasmas (2001)]. In addition to allowing that only rather low power pumps be used, photoionization introduces a damping of the short pulse which must be overcome by the Raman growth rate for net amplification to occur. The parameter space of gas densities, laser wavelengths, and laser intensities is surveyed to identify favorable regimes for this effect. Output laser intensities of 10(superscript ''17'') W/cm(superscript ''2'') for 0.5 mm radiation are found to be feasible for such a scheme using a pump of 10(superscript ''13'') W/cm(superscript ''2'') and an initial seed of 5 x 10(superscript ''14'') W/cm(superscript ''2'') over an amplification length of 5.6 cm in hydrogen gas.

D.S. Clark; N.J. Fisch

2001-10-04T23:59:59.000Z

423

Definition of Radiation  

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

Gamma Radiation and X-Rays Beta Radiation Alpha Radiation Irradiation Radioactive Contamination Definitions Detection Measurement Safety Around Radiation Sources Types of...

424

How to Detect Radiation  

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

How to Detect Radiation How to Survey Measurement Safety Around Radiation Sources Types of Radiation Exposure Managing Radiation Emergencies Procedure Demonstration Detection How...

425

Carbon-Supported IrNi Core-Shell Nanoparticles: Synthesis Characterization and Catalytic Activity  

Science Conference Proceedings (OSTI)

We synthesized carbon-supported IrNi core-shell nanoparticles by chemical reduction and subsequent thermal annealing in H{sub 2}, and verified the formation of Ir shells on IrNi solid solution alloy cores by various experimental methods. The EXAFS analysis is consistent with the model wherein the IrNi nanoparticles are composed of two-layer Ir shells and IrNi alloy cores. In situ XAS revealed that the Ir shells completely protect Ni atoms in the cores from oxidation or dissolution in an acid electrolyte under elevated potentials. The formation of Ir shell during annealing due to thermal segregation is monitored by time-resolved synchrotron XRD measurements, coupled with Rietveld refinement analyses. The H{sub 2} oxidation activity of the IrNi nanoparticles was found to be higher than that of a commercial Pt/C catalyst. This is predominantly due to Ni-core-induced Ir shell contraction that makes the surface less reactive for IrOH formation, and the resulting more metallic Ir surface becomes more active for H{sub 2} oxidation. This new class of core-shell nanoparticles appears promising for application as hydrogen anode fuel cell electrocatalysts.

K Sasaki; K Kuttiyiel; L Barrio; D Su; A Frenkel; N Marinkovic; D Mahajan; R Adzic

2011-12-31T23:59:59.000Z

426

Research priorities for occupational radiation protection  

Science Conference Proceedings (OSTI)

The Subpanel on Occupational Radiation Protection Research concludes that the most urgently needed research is that leading to the resolution of the potential effects of low-level ionizing radiation. This is the primary driving force in setting appropriate radiation protection standards and in directing the emphasis of radiation protection efforts. Much has already been done in collecting data that represents a compendium of knowledge that should be fully reviewed and understood. It is imperative that health physics researchers more effectively use that data and apply the findings to enhance understanding of the potential health effects of low-level ionizing radiation and improve the risk estimates upon which current occupational radiation protection procedures and requirements depend. Research must be focused to best serve needs in the immediate years ahead. Only then will we get the most out of what is accomplished. Beyond the above fundamental need, a number of applied research areas also have been identified as national priority issues. If effective governmental focus is achieved on several of the most important national priority issues, important occupational radiation protection research will be enhanced, more effectively coordinated, and more quickly applied to the work environment. Response in the near term will be enhanced and costs will be reduced by: developing microprocessor-aided {open_quotes}smart{close_quotes} instruments to simplify the use and processing of radiation data; developing more sensitive, energy-independent, and tissue-equivalent dosimeters to more accurately quantify personnel dose; and developing an improved risk assessment technology base. This can lead to savings of millions of dollars in current efforts needed to ensure personnel safety and to meet new, more stringent occupational guidelines.

Not Available

1994-02-01T23:59:59.000Z

427

Quantitative Vapor-phase IR Intensities and DFT Computations to Predict Absolute IR Spectra based on Molecular Structure: I. Alkanes  

SciTech Connect

Recently recorded quantitative IR spectra of a variety of gas-phase alkanes are shown to have integrated intensities in both the C-H stretching and C-H bending regions that depend linearly on the molecular size, i.e. the number of C-H bonds. This result is well predicted from CH4 to C15H32 by DFT computations of IR spectra at the B3LYP/6-31+G(d,p) level of DFT theory. A simple model predicting the absolute IR band intensities of alkanes based only on structural formula is proposed: For the C-H stretching band near 2930 cm-1 this is given by (in km/mol): CH_str = (343)*CH (4160) where CH is number of C-H bonds in the alkane. The linearity is explained in terms of coordinated motion of methylene groups rather than the summed intensities of autonomous -CH2- units. The effect of alkyl chain length on the intensity of a C-H bending mode is explored and interpreted in terms of conformer distribution. The relative intensity contribution of a methyl mode compared to the total C-H stretch intensity is shown to be linear in the number of terminal methyl groups in the alkane, and can be used to predict quantitative spectra a priori based on structure alone.

Williams, Stephen D.; Johnson, Timothy J.; Sharpe, Steven W.; Yavelak, Veronica; Oats, R. P.; Brauer, Carolyn S.

2013-11-13T23:59:59.000Z

428

Radiation dosimeter  

DOE Patents (OSTI)

A radiation detector readout circuit is provided which produces a radiation dose-rate readout from a detector even though the detector output may be highly energy dependent. A linear charge amplifier including an output charge pump circuit amplifies the charge signal pulses from the detector and pumps the charge into a charge storage capacitor. The discharge rate of the capacitor through a resistor is controlled to provide a time-dependent voltage which when integrated provides an output proportional to the dose-rate of radiation detected by the detector. This output may be converted to digital form for readout on a digital display.

Fox, Richard J. (Oak Ridge, TN)

1983-01-01T23:59:59.000Z

429

Radiation dosimeter  

DOE Patents (OSTI)

A radiation detector readout circuit is provided which produces a radiation dose-rate readout from a detector even through the detector output may be highly energy dependent. A linear charge amplifier including an output charge pump circuit amplifies the charge signal pulses from the detector and pumps the charge into a charge storage capacitor. The discharge rate of the capacitor through a resistor is controlled to provide a time-dependent voltage which when integrated provides an output proportional to the dose-rate of radiation detected by the detector. This output may be converted to digital form for readout on a digital display.

Fox, R.J.

1981-09-01T23:59:59.000Z

430

Radiation Hydrodynamics  

DOE Green Energy (OSTI)

The discipline of radiation hydrodynamics is the branch of hydrodynamics in which the moving fluid absorbs and emits electromagnetic radiation, and in so doing modifies its dynamical behavior. That is, the net gain or loss of energy by parcels of the fluid material through absorption or emission of radiation are sufficient to change the pressure of the material, and therefore change its motion; alternatively, the net momentum exchange between radiation and matter may alter the motion of the matter directly. Ignoring the radiation contributions to energy and momentum will give a wrong prediction of the hydrodynamic motion when the correct description is radiation hydrodynamics. Of course, there are circumstances when a large quantity of radiation is present, yet can be ignored without causing the model to be in error. This happens when radiation from an exterior source streams through the problem, but the latter is so transparent that the energy and momentum coupling is negligible. Everything we say about radiation hydrodynamics applies equally well to neutrinos and photons (apart from the Einstein relations, specific to bosons), but in almost every area of astrophysics neutrino hydrodynamics is ignored, simply because the systems are exceedingly transparent to neutrinos, even though the energy flux in neutrinos may be substantial. Another place where we can do ''radiation hydrodynamics'' without using any sophisticated theory is deep within stars or other bodies, where the material is so opaque to the radiation that the mean free path of photons is entirely negligible compared with the size of the system, the distance over which any fluid quantity varies, and so on. In this case we can suppose that the radiation is in equilibrium with the matter locally, and its energy, pressure and momentum can be lumped in with those of the rest of the fluid. That is, it is no more necessary to distinguish photons from atoms, nuclei and electrons, than it is to distinguish hydrogen atoms from helium atoms, for instance. There are all just components of a mixed fluid in this case. So why do we have a special subject called ''radiation hydrodynamics'', when photons are just one of the many kinds of particles that comprise our fluid? The reason is that photons couple rather weakly to the atoms, ions and electrons, much more weakly than those particles couple with each other. Nor is the matter-radiation coupling negligible in many problems, since the star or nebula may be millions of mean free paths in extent. Radiation hydrodynamics exists as a discipline to treat those problems for which the energy and momentum coupling terms between matter and radiation are important, and for which, since the photon mean free path is neither extremely large nor extremely small compared with the size of the system, the radiation field is not very easy to calculate. In the theoretical development of this subject, many of the relations are presented in a form that is described as approximate, and perhaps accurate only to order of {nu}/c. This makes the discussion cumbersome. Why are we required to do this? It is because we are using Newtonian mechanics to treat our fluid, yet its photon component is intrinsically relativistic; the particles travel at the speed of light. There is a perfectly consistent relativistic kinetic theory, and a corresponding relativistic theory of fluid mechanics, which is perfectly suited to describing the photon gas. But it is cumbersome to use this for the fluid in general, and we prefer to avoid it for cases in which the flow velocity satisfies {nu} << c. The price we pay is to spend extra effort making sure that the source-sink terms relating to our relativistic gas component are included in the equations of motion in a form that preserves overall conservation of energy and momentum, something that would be automatic if the relativistic equations were used throughout.

Castor, J I

2003-10-16T23:59:59.000Z

431

Dielectric liquid ionization chambers for detecting fast neutrons  

E-Print Network (OSTI)

Three ionization chambers with different geometries have been constructed and filled with dielectric liquids for detection of fast neutrons. The three dielectric liquids studied were Tetramethylsilane (TMS), Tetramethylpentane ...

Boyd, Erin M

2008-01-01T23:59:59.000Z

432

Impact of Low-Dose Ionizing Irradiation on Histone Modification...  

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

Impact of Low-Dose Ionizing Irradiation on Histone Modification and Chromatin Organization Hunter W. Richards Lawrence Berkeley National Laboratory Abstract Goal Our goal is to...

433

Impact of Low-Dose Ionizing Irradiation on Histone Modification...  

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

Low-Dose Ionizing Irradiation on Histone Modification and Chromatin Organization Hunter W. Richards, Steven D. Ayers, Shutao Cai, Yoshinori Kohwi, Gary Karpen, Sylvain Costes and...

434

Intense laser field ionization of atom and molecular ion.  

E-Print Network (OSTI)

??In order to understand how does the intense laser interact with matter we first of all study the ionization process. In this highly nonlinear region (more)

Long, Zi Jian

2008-01-01T23:59:59.000Z

435

Ionized channel generation of an intense-relativistic electron beam  

DOE Patents (OSTI)

A foilless intense relativistic electron beam generator uses an ionized cnel to guide electrons from a cathode passed an anode to a remote location.

Frost, Charles A. (Albuquerque, NM); Leifeste, Gordon T. (Albuquerque, NM); Shope, Steven L. (Albuquerque, NM)

1988-01-01T23:59:59.000Z

436

Soft ionization of thermally evaporated hypergolic ionic liquid aerosols  

E-Print Network (OSTI)

+ ][Dca ? ]. Figure 2. Aerosol particle size distribution ofhypergolic ionic liquid aerosols Christine J. Koh , Chen-ionization of evaporated IL aerosols Isolated ion pairs of a

Koh, Christine J.

2013-01-01T23:59:59.000Z

437

RADIATION DETECTOR  

DOE Patents (OSTI)

A radiation detector of the type is described wherein a condenser is directly connected to the electrodes for the purpose of performing the dual function of a guard ring and to provide capacitance coupling for resetting the detector system.

Wilson, H.N.; Glass, F.M.

1960-05-10T23:59:59.000Z

438

Low Dose Radiation Research Program: Impact of Genetic Factors on the  

NLE Websites -- All DOE Office Websites (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

439

Direct Determination of the Ionization Energies of PtC, PtO, and PtO2 with VUVRadiation  

SciTech Connect

Photoionization efficiency curves were measured for gas-phase PtC, PtO, and PtO2 using tunable vacuum ultraviolet (VUV) radiation at the Advanced Light Source. The molecules were prepared by laser ablation of a platinum tube, followed by reaction with CH4 or N2O and supersonic expansion. These measurements providethe first directly measured ionization energy for PtC, IE(PtC) = 9.45 +- 0.05 eV. The direct measurement also gives greatly improved ionization energies for the platinum oxides, IE(PtO) = 10.0 +- 0.1 eV and IE(PtO2) = 11.35 +- 0.05 eV. The ionization energy connects the dissociation energies of the neutral and cation, leading to greatly improved 0 K bond dissociation energies for the neutrals: D0(Pt-C) = 5.95 +- 0.07 eV, D0(Pt-O)= 4.30 +- 0.12 eV, and D0(OPt-O) = 4.41 +- 0.13 eV, as well as enthalpies of formation for the gas-phase molecules Delta H0 f,0(PtC(g)) = 701 +- 7 kJ/mol, Delta H0f,0(PtO(g)) = 396 +- 12 kJ/mol, and Delta H0f,0(PtO2(g)) = 218 +- 11 kJ/mol. Much of the error in previous Knudsen cell measurements of platinum oxide bond dissociation energies is due to the use of thermodynamic second law extrapolations. Third law values calculated using statistical mechanical thermodynamic functions are in much better agreement with values obtained from ionization energies and ion energetics. These experiments demonstrate that laser ablation production with direct VUV ionization measurements is a versatile tool to measure ionization energies and bond dissociation energies for catalytically interesting species such as metal oxides and carbides.

Citir, Murat; Metz, Ricardo B.; Belau, Leonid; Ahmed, Musahid

2008-07-21T23:59:59.000Z

440

Nevada Test Site Radiation Protection Program - Revision 1  

SciTech Connect

Title 10 Code of Federal Regulations (CFR) Part 835, 'Occupational Radiation Protection,' establishes radiation protection standards, limits, and program requirements for protecting individuals from ionizing radiation resulting from the conduct of U.S. Department of Energy (DOE) activities. 10 CFR 835.101(a) mandates that DOE activities be conducted in compliance with a documented Radiation Protection Program (RPP) as approved by DOE. This document promulgates the RPP for the Nevada Test Site (NTS), related (on-site or off-site) U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) operations, and environmental restoration off-site projects. This NTS RPP promulgates the radiation protection standards, limits, and program requirements for occupational exposure to ionizing radiation resulting from NNSA/NSO activities at the NTS and other operational areas as stated in 10 CFR 835.1(a). NNSA/NSO activities (including design, construction, operation, and decommissioning) within the scope of this RPP may result in occupational exposures to radiation or radioactive material. Therefore, a system of control is implemented through specific references to the site-specific NV/YMP RCM. This system of control is intended to ensure that the following criteria are met: (1) occupational exposures are maintained as low as reasonably achievable (ALARA), (2) DOE's limiting values are not exceeded, (3) employees are aware of and are prepared to cope with emergency conditions, and (4) employees are not inadvertently exposed to radiation or radioactive material.

Radiological Control Managers' Council

2008-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "ionizing radiation ir" 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

NIST Radiation thermometry  

Science Conference Proceedings (OSTI)

Radiation thermometry. Summary: ... Description: Radiation thermometers are calibrated using a range of variable-temperature blackbodies. ...

2011-10-13T23:59:59.000Z

442

NIST Optical Radiation Group  

Science Conference Proceedings (OSTI)

Optical Radiation Group. Welcome. The Optical Radiation Group maintains, improves, and disseminates the national scales ...

2013-07-29T23:59:59.000Z

443

CHEMICAL ANALYSIS OF A DIFFUSE CLOUD ALONG A LINE OF SIGHT TOWARD W51: MOLECULAR FRACTION AND COSMIC-RAY IONIZATION RATE  

Science Conference Proceedings (OSTI)

Absorption lines from the molecules OH{sup +}, H{sub 2}O{sup +}, and H{sup +} {sub 3} have been observed in a diffuse molecular cloud along a line of sight near W51 IRS2. We present the first chemical analysis that combines the information provided by all three of these species. Together, OH{sup +} and H{sub 2}O{sup +} are used to determine the molecular hydrogen fraction in the outskirts of the observed cloud, as well as the cosmic-ray ionization rate of atomic hydrogen. H{sup +} {sub 3} is used to infer the cosmic-ray ionization rate of H{sub 2} in the molecular interior of the cloud, which we find to be {zeta}{sub 2} = (4.8 {+-} 3.4) Multiplication-Sign 10{sup -16} s{sup -1}. Combining the results from all three species we find an efficiency factor-defined as the ratio of the formation rate of OH{sup +} to the cosmic-ray ionization rate of H-of {epsilon} = 0.07 {+-} 0.04, much lower than predicted by chemical models. This is an important step in the future use of OH{sup +} and H{sub 2}O{sup +} on their own as tracers of the cosmic-ray ionization rate.

Indriolo, Nick; Neufeld, D. A. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Gerin, M. [LERMA, CNRS, Observatoire de Paris and ENS, F-75231 Paris Cedex 05 (France); Geballe, T. R. [Gemini Observatory, Hilo, HI 96720 (United States); Black, J. H. [Department of Earth and Space Sciences, Chalmers University of Technology, Onsala Space Observatory, SE-43992 Onsala (Sweden); Menten, K. M. [MPI fuer Radioastronomie, D-53121 Bonn (Germany); Goicoechea, J. R. [Departamento de Astrofisica, Centro de Astrobiologia (CSIC-INTA), E-28850 Madrid (Spain)

2012-10-20T23:59:59.000Z

444

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

SciTech Connect

An environmental radiation real-time monitoring system with high pressure ionization chamber was developed. It has been installed permanently in the vicinity of Qinshan Nuclear Power Plant, the first built in mainland China. The system consists of four basic components: environmental radiation monitors; data communication network; a data processing center; and a remote terminal computer situated in Hangzhou. It has provided five million readings of environmental radiation levels as of January 1993. 8 refs., 1 fig., 3 tabs.

Minde Ding; Peiru Sheng; Zhangji Zhi [Suzhou Nuclear Research Institute, Jiangsu (China)

1996-03-01T23:59:59.000Z

445

Final report of the Committee on Interagency Radiation Research and Policy Coordination, 1984-1995  

SciTech Connect

This document is the final report of the Committee on Interagency Radiation Research and Policy Coordination (CIRRPC). The committee was established to address national and international issues involving ionizing and nonionizing radiation. Three sections are included in the report: a summary of CIRRPC`s history structure, and operations; CIRRPC`s most significant activities, findings and recommendations on national radiation issues of sufficient importance and scope to require interagency attention; topics for future consideration by Federal agencies.

NONE

1995-09-01T23:59:59.000Z

446

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

SciTech Connect

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

Kaneko, Masahito

1999-06-06T23:59:59.000Z

447

Low Dose Radiation Research Program: Molecular Characterization of the  

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

Molecular Characterization of the Roles of SOD Genes in Mammalian Molecular Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Authors: Chuan-Yuan Li, Zhanjun Guo, Zhonghui Yang, and Eric Chuang Institutions: Dept of Radiation Oncology, Duke University Medical Center, Durham, NC Advanced Technology Center, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland Background The potential risks of exposure to low dose radiation are of major concerns to the DOE/OBER Low Dose Radiation Research Program. It has been long recognized that much of the radiation-induced genetic damage to cells are caused by secondary oxidative species. Therefore internal cellular defense systems against oxidative stress play significant roles in countering genetic damage induced by ionizing radiation. The role of the detoxifying

448

Low Dose Radiation Research Program: 2003 Molecular Characterization of the  

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

Characterization of the Roles of SOD Genes in Mammalian Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Authors: Chuan-Yuan Li,1 Eric Chuang2 Institutions: 1Dept of Radiation Oncology, Duke University Medical Center, Durham, NC, 2Advanced Technology Center, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland The potential risks of exposure to low dose radiation are of major concerns to the DOE/OBER Low Dose Radiation Research Program. It has been long recognized that much of the radiation-induced genetic damage to cells are caused by secondary oxidative species. Therefore, internal cellular defense systems against oxidative stress play significant roles in countering genetic damage induced by ionizing radiation. The role of the detoxifying

449

Low Dose Radiation Research Program: DOE / NASA Joint Funded Projects  

NLE Websites -- All DOE Office Websites (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

450

OPEN MIDPLANE DIPOLE DESIGN FOR LHC IR UPGRADE.  

SciTech Connect

The proposed luminosity upgrade of the Large Hadron Collider (LHC), now under construction, will bring a large increase in the number of secondary particles from p-p collisions at the interaction point (IP). Energy deposition will be so large that the lifetime and quench performance of interaction region (IR) magnets may be significantly reduced if conventional designs are used. Moreover, the cryogenic capacity of the LHC will have to be significantly increased as the energy deposition load on the interaction region (IR) magnets by itself will exhaust the present capacity. We propose an alternate open midplane dipole design concept for the dipole-first optics that mitigates these issues. The proposed design takes advantage of the fact that most of the energy is deposited in the midplane region. The coil midplane region is kept free of superconductor, support structure and other material. Initial energy deposition calculations show that the increase in temperature remains within the quench tolerance of the superconducting coils. In addition, most of the energy is deposited in a relatively warm region where the heat removal is economical. We present the basic concept and preliminary design that includes several innovations.

GUPTA,R.; ANERELLA,M.; HARRISON,M.; SCHMALZLE,J.; MOKHOV,N.

2004-01-21T23:59:59.000Z

451

High Resolution FIR and IR Spectroscopy of Methanol Isotopologues  

Science Conference Proceedings (OSTI)

New astronomical facilities such as HIFI on the Herschel Space Observatory, the SOFIA airborne IR telescope and the ALMA sub-mm telescope array will yield spectra from interstellar and protostellar sources with vastly increased sensitivity and frequency coverage. This creates the need for major enhancements to laboratory databases for the more prominent interstellar 'weed' species in order to model and account for their lines in observed spectra in the search for new and more exotic interstellar molecular 'flowers'. With its large-amplitude internal torsional motion, methanol has particularly rich spectra throughout the FIR and IR regions and, being very widely distributed throughout the galaxy, is perhaps the most notorious interstellar weed. Thus, we have recorded new spectra for a variety of methanol isotopic species on the high-resolution FTIR spectrometer on the CLS FIR beamline. The aim is to extend quantum number coverage of the data, improve our understanding of the energy level structure, and provide the astronomical community with better databases and models of the spectral patterns with greater predictive power for a range of astrophysical conditions.

Lees, R. M.; Xu, Li-Hong [Centre for Laser, Atomic and Molecular Studies (CLAMS), University of New Brunswick, 100 Tucker Park Road, Saint John, NB E2L 4L5 (Canada); Appadoo, D. R. T.; Billinghurst, B. [Canadian Light Source, Univ. of Saskatchewan, 101 Perimeter Rd, Saskatoon, SK S7N 0X4 (Canada)

2010-02-03T23:59:59.000Z

452

The Nature of Ionized Gas in Giant Elliptical Galaxies  

E-Print Network (OSTI)

I review the current understanding of the origin and nature of ``warm'' ionized gas in giant elliptical galaxies in the light of results of recent imaging and spectroscopic surveys. CCD imaging surveys have revealed that emission-line disks or filaments are (as a rule) associated with dust absorption, even in the X-ray brightest systems. This strongly suggests that the origin of this ionized gas is generally not through ``cooling flows''; galaxy interactions are favored instead. Using data from a new spectrophotometric survey of ``normal'' elliptical galaxies covering the whole optical range, the extended ionized gas in giant ellipticals is found to be --without exception-- of the LINER class, and most probably NOT powered by star formation activity. I discuss two independent pieces of evidence which suggest that the extended gas in giant ellipticals is ionized by means of a distributed source of ionization: (i) A significant correlation exists between the H-alpha+[NII]luminosity and the optical luminosity within the region occupied by the ionized gas, and (ii) the ionization parameter of the gas does not change significantly with galactocentric radius. Two potential sources of ionization are evaluated: Photoionization by old hot stars (of post-AGB and/or AGB-Manque' type) and mechanical energy flux from electron conduction in hot, X-ray-emitting gas.

Paul Goudfrooij

1998-09-04T23:59:59.000Z

453

Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation  

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

Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent ion fragmentation dynamics in nanoclusters composed of argon (Ar) shells and xenon (Xe) cores. The clusters were site-selectively ionized (i.e, ionization took place either in the xenon core or in the argon shell). Using a high-resolution photoelectron-ion coincidence technique at ALS Beamlines 10.0.1 and 11.0.2, the researchers concluded that charge-transfer processes and fragmentation dynamics are strongly influenced by the environment of the initially ionized atoms.

454

Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation  

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

Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent ion fragmentation dynamics in nanoclusters composed of argon (Ar) shells and xenon (Xe) cores. The clusters were site-selectively ionized (i.e, ionization took place either in the xenon core or in the argon shell). Using a high-resolution photoelectron-ion coincidence technique at ALS Beamlines 10.0.1 and 11.0.2, the researchers concluded that charge-transfer processes and fragmentation dynamics are strongly influenced by the environment of the initially ionized atoms.

455

Radiation receiver  

DOE Patents (OSTI)

The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles. 5 figs.

Hunt, A.J.

1983-09-13T23:59:59.000Z

456

Radiation receiver  

SciTech Connect

The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

Hunt, Arlon J. (Oakland, CA)

1983-01-01T23:59:59.000Z

457

SIZE AND TEMPERATURE DEPENDENCE IN THE FAR-IR SPECTRA OF WATER ICE PARTICLES  

SciTech Connect

Spectra of water-ice aerosol particles have been measured in the far-IR region using synchrotron radiation. The particles in the nanoscale size regime of 1-100 nm were formed by rapid collisional cooling at temperatures ranging from 4 to 190 K. The spectra show the characteristic bands centered near 44 {mu}m (230 cm{sup -1}) and 62 {mu}m (160 cm{sup -1}) associated with the intermolecular lattice modes of crystalline ice at all temperatures, in contrast to previous studies of thin films formed by vapor deposition where amorphous ice is generated below 140 K. The bands shift to higher wavenumber values as the temperature is reduced, consistent with the trend seen in earlier studies, but in our experiments the actual peak positions in the aerosol particle spectra are consistently higher by ca. 4 cm{sup -1}. This finding has implications for the potential use of these spectral features as a temperature probe. The particle sizes are small enough for their spectra to be free of scattering effects, and therefore provide a means to assess imaginary refractive index values obtained through Kramers-Kronig analyses of thin film spectra.

Medcraft, Chris; McNaughton, Don; Thompson, Chris D. [School of Chemistry, Monash University, Wellington Road, Clayton, Victoria 3800 (Australia); Appadoo, Dominique [Australian Synchrotron, Blackburn Road, Clayton, Victoria 3168 (Australia); Bauerecker, Sigurd [Institut fuer Physikalische und Theoretische Chemie, Technische Universitaet Braunschweig, Hans-Sommer-Strasse 10, D-38106 Braunschweig (Germany); Robertson, Evan G., E-mail: E.Robertson@latrobe.edu.au [Department of Chemistry and La Trobe Institute of Molecular Sciences, La Trobe University, Bundoora, Victoria 3086 (Australia)

2012-10-10T23:59:59.000Z

458

RADIATION SOURCES  

DOE Patents (OSTI)

A novel long-lived source of gamma radiation especially suitable for calibration purposes is described. The source of gamma radiation is denoted mock iodine131, which comprises a naixture of barium-133 and cesium-137. The barium and cesium are present in a barium-cesium ratio of approximately 5.7/1 to 14/1, uniformly dispersed in an ion exchange resin and a filter surrounding the resin comprised of a material of atomic number below approximately 51, and substantially 0.7 to 0.9 millimeter thick.

Brucer, M.H.

1958-04-15T23:59:59.000Z

459

Regulation Of Nf=kb And Mnsod In Low Dose Radiation Induced Adaptive Protection Of Mouse And Human Skin Cells  

Science Conference Proceedings (OSTI)

A sampling of publications resulting from this grant is provided. One is on the subject of NF-κB-Mediated HER2 Overexpression in Radiation-Adaptive Resistance. Another is on NF-κB-mediated adaptive resistance to ionizing radiation.

Jian Li

2012-11-07T23:59:59.000Z

460

IR differential-absorption lidars for ecological monitoring of the environment  

Science Conference Proceedings (OSTI)

A review of studies on lidar sensing of the environment by the method of IR differential absorption is presented. The differential-absorption method is described and its various applications are considered. A comparison of this method with other methods of lidar sensing showed that a differential-absorption lidar successfully supplements a Raman lidar. The basic parameters are presented for IR lidars fabricated recently by various research groups. The outlook for the IR lidar sensing of the atmosphere is discussed. (review)

Vasil'ev, B I [P.N. Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Mannoun, Oussama [Moscow Institute of Physics and Technology (State University), Dolgoprudnyi, Moscow Region (Russian Federation)

2006-09-30T23:59:59.000Z

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461

Radiation Protection Act (Pennsylvania)  

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

This Act combines the radiation safety provisions of The Atomic Energy Development and Radiation Control Act and the Environmental Radiation Protection Act, and empowers the Department of...

462

Radiation Tolerant Metallic Multilayers  

Science Conference Proceedings (OSTI)

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

463

NEW SOURCES OF RADIATION  

E-Print Network (OSTI)

Stanford Synchrotron Radiation Project Report No. 75/07.IBL 79M0733 Fig. 20. Radiation emission pattern by electronsWinick, Stanford Synchrotron Radiation Laboratory. Fig. 21.

Schimmerling, W.

2010-01-01T23:59:59.000Z

464

Radiation-induced angiosarcoma  

E-Print Network (OSTI)

1a Figure 1b Figure 1. Radiation-induced angiosarcoma in afollowing completion of radiation therapy. Figure 2a Figurecell histiocytosis after radiation for breast carcinoma: can

Anzalone, C Lane; Cohen, Philip R; Diwan, Abdul H; Prieto, Victor G

2013-01-01T23:59:59.000Z

465

BNL NASA Space Radiation Laboratory  

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

Dosimetry Calibration: Primary Ion Chamber Dosimetry Calibration: Primary Ion Chamber Dosimetry Calibration: Secondary Ion Chamber Dosimetry Calibration: Secondary Ion Chamber with Gain Dosimetry Calibration: Scintillator Based Dosimetry Dosimetry Calibration: Primary Ion Chamber The primary method of calibrating the dose delivered at NSRL is via a small ion chamber called a "Calibration Ion Chamber" (aka EGG counter) produced by Far West Technology. This is an air-filled bulb with electrodes for collecting ionization inside a tissue-equivalent plastic cap. The Calibration Ion Chamber is sent back to the manufacturer yearly to be calibrated using a standard gamma ray source (Cs-137). The calibration is based on a standard defied by the International Commission on Radiation Units and Measurements (ICRU) and reported in their ICRU Report 59, 15 December 1998.

466

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

SciTech Connect

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

Fabrikant, J.I.

1980-01-01T23:59:59.000Z

467

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

E-Print Network (OSTI)

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