Science.gov

Sample records for radiation processes annual

  1. Radiative processes

    NASA Technical Reports Server (NTRS)

    Frederick, J. E.; Leovy, C.; Anderson, D. E., Jr.; Anderson, G. P.; Dickinson, R. E.; Drayson, S. R.; Fels, S.; Hall, L. A.; Kiehl, J.; Mentall, J. E.

    1985-01-01

    Solar radiation and the processes that control its deposition in the Earth atmosphere are considered. The published data obtained since 1978 define a reference solar spectral irradiance for use in atmospheric chemical and dynamical studies, while long term satellite measurements are now providing information on variations in the output of the Sun over a range of time scales. As concerns absorption of solar radiation in the atmosphere, new cross section data for molecular oxygen and ozone are now available. Line-by-line calculations used to predict infrared flux divergences, both as regards assumptions made in radiative transfer calculations and in the spectroscopic parameters used as inputs are examined. Also examined are the influence of radiative processes on planetary scale wave activity, photochemical acceleration of radiative damping, and the breakdown of local thermodynamic equilibrium at mesospheric altitudes.

  2. A retrospective study on annual evaluation of radiation processing for frozen bone allografts complying to quality system requirements.

    PubMed

    Ramalingam, Saravana; Mohd, Suhaili; Samsuddin, Sharifah Mazni; Min, N G Wuey; Yusof, Norimah; Mansor, Azura

    2015-12-01

    Bone allografts have been used widely to fill up essential void in orthopaedic surgeries. The benefit of using allografts to replace and reconstruct musculoskeletal injuries, fractures or disease has obtained overwhelming acceptance from orthopaedic surgeons worldwide. However, bacterial infection and disease transmission through bone allograft transplantation have always been a significant issue. Sterilization by radiation is an effective method to eliminate unwanted microorganisms thus assist in preventing life threatening allograft associated infections. Femoral heads procured from living donors and long bones (femur and tibia) procured from cadaveric donors were sterilized at 25 kGy in compliance with international standard ISO 11137. According to quality requirements, all records of bone banking were evaluated annually. This retrospective study was carried out on annual evaluation of radiation records from 1998 until 2012. The minimum doses absorbed by the bones were ranging from 25.3 to 38.2 kGy while the absorbed maximum doses were from 25.4 to 42.3 kGy. All the bones supplied by our UMMC Bone Bank were sterile at the required minimum dose of 25 kGy. Our analysis on dose variation showed that the dose uniformity ratios in 37 irradiated boxes of 31 radiation batches were in the range of 1.003-1.251, which indicated the doses were well distributed. PMID:25687771

  3. Annual Cycle of Surface Longwave Radiation

    NASA Technical Reports Server (NTRS)

    Mlynczak, Pamela E.; Smith, G. Louis; Wilber, Anne C.; Stackhouse, Paul W.

    2011-01-01

    The annual cycles of upward and downward longwave fluxes at the Earth s surface are investigated by use of the NASA/GEWEX Surface Radiation Budget Data Set. Because of the immense difference between the heat capacity of land and ocean, the surface of Earth is partitioned into these two categories. Principal component analysis is used to quantify the annual cycles. Over land, the first principal component describes over 95% of the variance of the annual cycle of the upward and downward longwave fluxes. Over ocean the first term describes more than 87% of these annual cycles. Empirical orthogonal functions show the corresponding geographical distributions of these cycles. Phase plane diagrams of the annual cycles of upward longwave fluxes as a function of net shortwave flux show the thermal inertia of land and ocean.

  4. The annual cycle of Earth emitted radiation distribution

    NASA Technical Reports Server (NTRS)

    Bess, T. D.; Smith, G. L.

    1979-01-01

    Measurements of longwave radiation from the Earth Radiation Budget (ERB) experiment aboard the Nimbus 6 spacecraft have been analyzed to show the annual cycle of the distribution of Earth emitted radiation.

  5. Annual Cycles of Surface Shortwave Radiative Fluxes

    NASA Technical Reports Server (NTRS)

    Wilber, Anne C.; Smith, G. Louis; Gupta, Shashi K.; Stackhouse, Paul W.

    2006-01-01

    The annual cycles of surface shortwave flux are investigated using the 8-yr dataset of the surface radiation budget (SRB) components for the period July 1983-June 1991. These components include the downward, upward, and net shortwave radiant fluxes at the earth's surface. The seasonal cycles are quantified in terms of principal components that describe the temporal variations and empirical orthogonal functions (EOFs) that describe the spatial patterns. The major part of the variation is simply due to the variation of the insolation at the top of the atmosphere, especially for the first term, which describes 92.4% of the variance for the downward shortwave flux. However, for the second term, which describes 4.1% of the variance, the effect of clouds is quite important and the effect of clouds dominates the third term, which describes 2.4% of the variance. To a large degree the second and third terms are due to the response of clouds to the annual cycle of solar forcing. For net shortwave flux at the surface, similar variances are described by each term. The regional values of the EOFs are related to climate classes, thereby defining the range of annual cycles of shortwave radiation for each climate class.

  6. Current state of radiation processing

    NASA Astrophysics Data System (ADS)

    Pikaev, Alexei K.

    1995-06-01

    A review of common trends in the development of modern radiation processing is presented. The sources of ionising radiation and the most important processes practically induced under the influence of this radiation are discussed. It is shown that radiation methods can be used successfully for the modification of materials, for the sterilisation of medical articles, for the solution of ecological problems, for treatment of food products, in radiation engineering, etc. Special attention is paid to processes at the pilot plant and industrial scales. The bibliography includes 548 references.

  7. Atmospheric Radiation Measurement Climate Research Facility (ACRF) Annual Report 2007

    SciTech Connect

    LR Roeder

    2007-12-01

    This annual report describes the purpose and structure of the program, and presents key accomplishments in 2007. Notable achievements include: • Successful review of the ACRF as a user facility by the DOE Biological and Environmental Research Advisory Committee. The subcommittee reinforced the importance of the scientific impacts of this facility, and its value for the international research community. • Leadership of the Cloud Land Surface Interaction Campaign. This multi-agency, interdisciplinary field campaign involved enhanced surface instrumentation at the ACRF Southern Great Plains site and, in concert with the Cumulus Humilis Aerosol Processing Study sponsored by the DOE Atmospheric Science Program, coordination of nine aircraft through the ARM Aerial Vehicles Program. • Successful deployment of the ARM Mobile Facility in Germany, including hosting nearly a dozen guest instruments and drawing almost 5000 visitors to the site. • Key advancements in the representation of radiative transfer in weather forecast models from the European Centre for Medium-Range Weather Forecasts. • Development of several new enhanced data sets, ranging from best estimate surface radiation measurements from multiple sensors at all ACRF sites to the extension of time-height cloud occurrence profiles to Niamey, Niger, Africa. • Publication of three research papers in a single issue (February 2007) of the Bulletin of the American Meteorological Society.

  8. Thermal effects in radiation processing

    SciTech Connect

    Zagorski, Z.P.

    1984-10-21

    The balance of ionizing radiation energy incident on an object being processed is discussed in terms of energy losses, influencing the amount really absorbed. To obtain the amount of heat produced, the absorbed energy is corrected for the change in internal energy of the system and for the heat effect of secondary reactions developing after the initiation. The temperature of a processed object results from the heat evolved and from the specific heat of the material comprising the object. The specific heat of most materials is usually much lower than that of aqueous systems and therefore temperatures after irradiation are higher. The role of low specific heat in radiation processing at cryogenic conditions is stressed. Adiabatic conditions of accelerator irradiation are contrasted with the steady state thermal conditions prevailing in large gamma sources. Among specific questions discussed in the last part of the paper are: intermediate and final temperature of composite materials, measurement of real thermal effects in situ, neutralization of undesired warming experienced during radiation processing, processing at temperatures other than ambient and administration of very high doses of radiation.

  9. Radiation processing and market economy

    NASA Astrophysics Data System (ADS)

    Zagórski, Z. P.

    1998-06-01

    In the system of totalitarian economy, regulated by bureaucracy, the real value of equipment, materials and services is almost completely unknown, what makes impossible the comparison of different technologies, eliminates competition, disturbs research and development. With introduction of market economy in Central and Eastern Europe, the radiation processing has lost doubtful support, becoming an independent business, subject to laws of free market economy. Only the most valuable objects of processing have survived that test. At the top of the list are: radiation sterilization of medical equipment and radiation induced crosslinking of polymers, polyethylene in particular. New elements of competition has entered the scene, as well as questions of international regulations and standards have appeared.

  10. Annual Cycle of Cloud Forcing of Surface Radiation Budget

    NASA Technical Reports Server (NTRS)

    Wilber, Anne C.; Smith, G. Louis; Stackhouse, Paul W., Jr.; Gupta, Shashi K.

    2006-01-01

    The climate of the Earth is determined by its balance of radiation. The incoming and outgoing radiation fluxes are strongly modulated by clouds, which are not well understood. The Earth Radiation Budget Experiment (Barkstrom and Smith, 1986) provided data from which the effects of clouds on radiation at the top of the atmosphere (TOA) could be computed (Ramanathan, 1987). At TOA, clouds increase the reflected solar radiation, tending to cool the planet, and decrease the OLR, causing the planet to retain its heat (Ramanathan et al., 1989; Harrison et al., 1990). The effects of clouds on radiation fluxes are denoted cloud forcing. These shortwave and longwave forcings counter each other to various degrees, so that in the tropics the result is a near balance. Over mid and polar latitude oceans, cloud forcing at TOA results in large net loss of radiation. Here, there are large areas of stratus clouds and cloud systems associated with storms. These systems are sensitive to surface temperatures and vary strongly with the annual cycle. During winter, anticyclones form over the continents and move to the oceans during summer. This movement of major cloud systems causes large changes of surface radiation, which in turn drives the surface temperature and sensible and latent heat released to the atmosphere.

  11. Assessment of radiative feedback in climate models using satellite observations of annual flux variation.

    PubMed

    Tsushima, Yoko; Manabe, Syukuro

    2013-05-01

    In the climate system, two types of radiative feedback are in operation. The feedback of the first kind involves the radiative damping of the vertically uniform temperature perturbation of the troposphere and Earth's surface that approximately follows the Stefan-Boltzmann law of blackbody radiation. The second kind involves the change in the vertical lapse rate of temperature, water vapor, and clouds in the troposphere and albedo of the Earth's surface. Using satellite observations of the annual variation of the outgoing flux of longwave radiation and that of reflected solar radiation at the top of the atmosphere, this study estimates the so-called "gain factor," which characterizes the strength of radiative feedback of the second kind that operates on the annually varying, global-scale perturbation of temperature at the Earth's surface. The gain factor is computed not only for all sky but also for clear sky. The gain factor of so-called "cloud radiative forcing" is then computed as the difference between the two. The gain factors thus obtained are compared with those obtained from 35 models that were used for the fourth and fifth Intergovernmental Panel on Climate Change assessment. Here, we show that the gain factors obtained from satellite observations of cloud radiative forcing are effective for identifying systematic biases of the feedback processes that control the sensitivity of simulated climate, providing useful information for validating and improving a climate model. PMID:23613585

  12. Dose assurance in radiation processing plants

    NASA Astrophysics Data System (ADS)

    Miller, A.; Chadwick, K. H.; Nam, J. W.

    Radiation processing relies to a large extent on dosimetry as control of proper operation. This applies in particular to radiation sterilization of medical products and food treatment, but also during development of any other process. The assurance that proper dosimetry is performed at the radiation processing plant can be obtained through the mediation of an international organization, and the IAEA is now implementing a dose assurance service for industrial radiation processing.

  13. Microclimate of a desert playa: evaluation of annual radiation, energy, and water budgets components

    NASA Astrophysics Data System (ADS)

    Malek, Esmaiel

    2003-03-01

    We set up two automatic weather stations over a playa (the flat floor of an undrained desert basin that, at times, becomes a shallow lake), approximately 65 km east-west by 130 km north-south, located in Dugway (40° 08N, 113° 27W, 1124 m above mean sea level) in northwestern Utah, USA, in 1999. These stations measured the radiation budget components, namely: incoming Rsi and outgoing Rso solar or shortwave radiation, using two Kipp and Zonen pyranometers (one inverted), the incoming Rli (or atmospheric) and outgoing Rlo (or terrestrial) longwave radiation, using two Kipp and Zonen pyrgeometers (one inverted) during the year 2000. These sensors were ventilated throughout the year to prevent dew and frost formation. Summation of these components yields the net radiation Rn. We also measured the air temperatures and humidity at 1 and 2 m and the soil moisture and temperature (Campbell Sci., Inc., CSI) to evaluate the energy budget components (latent (LE), sensible (H), and the soil (Gsur) heat fluxes). The 10 m wind speed U10 and direction (R.M. Young wind monitor), precipitation (CSI), and the surface temperature (Radiation and Energy Balance Systems, REBS) were also measured during 2000. The measurements were taken every 2 s, averaged into 20 min, continuously, throughout the year 2000. The annual comparison of radiation budget components indicates that about 34% of the annual Rsi (6937.7 MJ m-2 year-1) was reflected back to the sky as Rso, with Rli and Rlo amounting to 9943.4 MJ m-2 year-1 and 12 789.7 MJ m-2 year-1 respectively. This yields about 1634.3 MJ m-2 year-1 as Rn, which is about 24% of the annual Rsi. Of the total 1634.3 MJ m-2 year-1 available energy, about 25% was used for the process of evaporation (LE) and 77% for heating the air (H). The annual heat contribution from the soil to the energy budget amounted to 2% during the experimental period. Our studies showed that the total annual measured precipitation amounted to 108.0 mm year-1 during the

  14. Apparatus for processing electromagnetic radiation and method

    NASA Technical Reports Server (NTRS)

    Gatewood, George D. (Inventor)

    1983-01-01

    Measuring apparatus including a ruled member having alternate transparent and opaque zones. An optical coupler connecting the ruled member with electromagnetic radiation-conversion apparatus. The conversion apparatus may include a photomultiplier and a discriminator. Radiation impinging on the ruled member will, in part, be converted to electrical pulses which correspond to the intensity of the radiation. A method of processing electromagnetic radiation includes providing a member having alternating dark and light zones, establishing movement of the member through the beam of electromagnetic radiation with the dark zones interrupting passage of radiation through the rule, providing an optical coupler to connect a portion of the radiation with a conversion station where the radiation portion is converted into an electrical pulse which is related to the intensity of the radiation received at the conversion station. The electrical pulses may be counted and the digitized signals stored or permanently recorded to produce positional information.

  15. Session on modeling of radiative transfer processes

    NASA Technical Reports Server (NTRS)

    Flatau, Piotr

    1993-01-01

    The session on modeling of radiative transfer processes is reviewed. Six critical issues surfaced in the discussion concerning scale-interactive radiative processes relevent to the mesoscale convective systems (MCS's). These issues are the need to expand basic knowledge of how MCS's influence climate through extensive cloud shields and increased humidity in the upper troposphere; to improve radiation parameterizations used in mesoscale and General Circulation Model (GCM) models; to improve our basic understanding of the influence of radiation on MCS dynamics due to diabatic heating, production of condensate, and vertical and horizontal heat fluxes; to quantify our understanding of radiative impacts of MCS's on the surface and free atmosphere energy budgets; to quantify and identify radiative and microphysical processes important in the evolution of MCS's; and to improve the capability to remotely sense MCS radiative properties from space and ground-based systems.

  16. New trends of radiation processing applications

    NASA Astrophysics Data System (ADS)

    Machi, Sueo

    1996-03-01

    Major fields of radiation processing applications are: polymeric materials, food processing, sterilization of medical products and environmental conservation. There are about 200 60Co gamma irradiation facilities and 700 electron beam accelerators, mainly for commercial purposes, throughout the world. Radiation cross-linking and grafting techniques of polymeric materials have been providing many unique products including heat materials, heat shrinkable materials, curing of coatings and battery separators. Extensive studies have been devoted to the development of bio-medical materials using radiation processing to prepare bio-compatible materials and controlled release of drugs. New wound dressings have been successfully developed in Poland and Israel for commercial clinical use.

  17. Chemical Processes in Astrophysical Radiation Fields

    SciTech Connect

    Stancil, P.C.; Dalgarno, A.

    1997-12-31

    The effects of stimulated photon emission on chemical processes in a radiation field are considered and their influence on the chemistry of the early universe and other astrophysical environments is investigated. Spontaneous and stimulated radiative attachment rate coefficients for H(-), Li(-) and C(-) are presented.

  18. Effect of radiation processing on meat tenderisation

    NASA Astrophysics Data System (ADS)

    Kanatt, Sweetie R.; Chawla, S. P.; Sharma, Arun

    2015-06-01

    The effect of radiation processing (0, 2.5, 5 and 10 kGy) on the tenderness of three types of popularly consumed meat in India namely chicken, lamb and buffalo was investigated. In irradiated meat samples dose dependant reduction in water holding capacity, cooking yield and shear force was observed. Reduction in shear force upon radiation processing was more pronounced in buffalo meat. Protein and collagen solubility as well as TCA soluble protein content increased on irradiation. Radiation processing of meat samples resulted in some change in colour of meat. Results suggested that irradiation leads to dose dependant tenderization of meat. Radiation processing of meat at a dose of 2.5 kGy improved its texture and had acceptable odour.

  19. 2D Radiative Processes Near Cloud Edges

    NASA Technical Reports Server (NTRS)

    Varnai, T.

    2012-01-01

    Because of the importance and complexity of dynamical, microphysical, and radiative processes taking place near cloud edges, the transition zone between clouds and cloud free air has been the subject of intense research both in the ASR program and in the wider community. One challenge in this research is that the one-dimensional (1D) radiative models widely used in both remote sensing and dynamical simulations become less accurate near cloud edges: The large horizontal gradients in particle concentrations imply that accurate radiative calculations need to consider multi-dimensional radiative interactions among areas that have widely different optical properties. This study examines the way the importance of multidimensional shortwave radiative interactions changes as we approach cloud edges. For this, the study relies on radiative simulations performed for a multiyear dataset of clouds observed over the NSA, SGP, and TWP sites. This dataset is based on Microbase cloud profiles as well as wind measurements and ARM cloud classification products. The study analyzes the way the difference between 1D and 2D simulation results increases near cloud edges. It considers both monochromatic radiances and broadband radiative heating, and it also examines the influence of factors such as cloud type and height, and solar elevation. The results provide insights into the workings of radiative processes and may help better interpret radiance measurements and better estimate the radiative impacts of this critical region.

  20. Silicon web process development. Annual report

    SciTech Connect

    Duncan, C.S.; Seidensticker, R.G.; McHugh, J.P.; Hill, F.E.; Skutch, M.E.; Driggers, J.M.; Hopkins, R.H.

    1980-06-30

    During this reporting period significant milestones have been met. A new barrier crucible design which consistently maintains melt stability over long periods of time has been successfully tested and used in long growth runs. The pellet feeder for melt replenishment was operated continuously for growth runs of up to 17 hours (a one day growth cycle). The liquid level sensor comprising a laser/sensor system was operated, performed well, and meets the requirements for maintaining liquid level height during growth and melt replenishment. An automated feedback loop connecting the feed mechanism and the liquid level sensing system was designed and constructed and, during the preparation of this report, operated successfully for 3 1/2 hours demonstrating the feasibility of semi-automated dendritic web growth. The web throughput task has resulted in a demonstration of wider good quality web as well as a demonstration of higher throughput rates. The accomplishments during the report period are described in detail. The economic analysis of the dendritic web process was updated. The sensitivity of the cost of sheet to variations in capital equipment cost and recycling dendrites was calculated; and it was shown that these factors have relatively little impact on sheet cost. An important finding was that dendrites from web which had gone all the way through the solar cell fabrication process, when melted and grown into web, produce crystals which show no degradation in cell efficiency. Material quality remains high and cells made from web grown at the start, during, and the end of a run from a replenished melt show comparable efficiencies.

  1. Annual Report: Hydrodynamics and Radiative Hydrodynamics with Astrophysical Applications

    SciTech Connect

    R. Paul Drake

    2005-12-01

    We report the ongoing work of our group in hydrodynamics and radiative hydrodynamics with astrophysical applications. During the period of the existing grant, we have carried out two types of experiments at the Omega laser. One set of experiments has studied radiatively collapsing shocks, obtaining high-quality scaling data using a backlit pinhole and obtaining the first (ever, anywhere) Thomson-scattering data from a radiative shock. Other experiments have studied the deeply nonlinear development of the Rayleigh-Taylor (RT) instability from complex initial conditions, obtaining the first (ever, anywhere) dual-axis radiographic data using backlit pinholes and ungated detectors. All these experiments have applications to astrophysics, discussed in the corresponding papers either in print or in preparation. We also have obtained preliminary radiographs of experimental targets using our x-ray source. The targets for the experiments have been assembled at Michigan, where we also prepare many of the simple components. The above activities, in addition to a variety of data analysis and design projects, provide good experience for graduate and undergraduates students. In the process of doing this research we have built a research group that uses such work to train junior scientists.

  2. Maximal acceleration and radiative processes

    NASA Astrophysics Data System (ADS)

    Papini, Giorgio

    2015-08-01

    We derive the radiation characteristics of an accelerated, charged particle in a model due to Caianiello in which the proper acceleration of a particle of mass m has the upper limit 𝒜m = 2mc3/ℏ. We find two power laws, one applicable to lower accelerations, the other more suitable for accelerations closer to 𝒜m and to the related physical singularity in the Ricci scalar. Geometrical constraints and power spectra are also discussed. By comparing the power laws due to the maximal acceleration (MA) with that for particles in gravitational fields, we find that the model of Caianiello allows, in principle, the use of charged particles as tools to distinguish inertial from gravitational fields locally.

  3. 40 CFR 35.9015 - Summary of annual process.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Summary of annual process. 35.9015 Section 35.9015 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Financial Assistance for the National Estuary Program § 35.9015...

  4. 40 CFR 35.9015 - Summary of annual process.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Summary of annual process. 35.9015 Section 35.9015 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Financial Assistance for the National Estuary Program § 35.9015...

  5. 40 CFR 35.9015 - Summary of annual process.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Summary of annual process. 35.9015 Section 35.9015 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Financial Assistance for the National Estuary Program § 35.9015...

  6. 40 CFR 35.9015 - Summary of annual process.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Summary of annual process. 35.9015 Section 35.9015 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Financial Assistance for the National Estuary Program § 35.9015...

  7. 40 CFR 35.9015 - Summary of annual process.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Summary of annual process. 35.9015 Section 35.9015 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Financial Assistance for the National Estuary Program § 35.9015...

  8. Progress in radiation processing of polymers

    NASA Astrophysics Data System (ADS)

    Chmielewski, Andrzej G.; Haji-Saeid, Mohammad; Ahmed, Shamshad

    2005-07-01

    Modification in polymeric structure of plastic material can be brought either by conventional chemical means or by exposure to ionization radiation from ether radioactive sources or highly accelerated electrons. The prominent drawbacks of chemical cross-linking typically involve the generation of noxious fumes and by products of peroxide degradation. Both the irradiation sources have their merits and limitations. Increased utilization of electron beams for modification and enhancement of polymer materials has been in particular witnessed over the past 40 years. The paper highlights several recent cases of EB utilization to improve key properties of selected plastic products. In paper is provided a survey of radiation processing methods of industrial interest, encompassing technologies which are already commercially well established, through developments in the active R&D stage which show pronounced promise for future commercial use. Radiation cross-linking technologies discussed include: application in cable and wire, application in rubber tyres, radiation vulcanization of rubber latex, development of radiation crosslinked SiC fiber, polymer recycling, development of gamma compatible pp, hydrogels etc. Over the years, remarkable advancement has been achieved in radiation processing of natural polymers. Role of radiation in improving the processing of temperature of PCL for use as biodegradable polymer, in accelerated breakdown of cellulose into viscose and enhancement in yields of chitin/chitosan from sea-food waste, is described.

  9. The topographic distribution of annual incoming solar radiation in the Rio Grande River Basin

    NASA Astrophysics Data System (ADS)

    Dubayah, R.; van Katwijk, V.

    1992-11-01

    We model the annual incoming solar radiation topoclimatology for the Rio Grande River basin in Colorado, U.S.A. Hourly pyranometer measurements are combined with satellite reflectance data and 30 m digital elevation models within a topographic solar radiation algorithm. Our results show that there is large spatial variability within the basin, even at an annual integration length, but the annual, basin-Wide mean is close to that measured by the pyranometers. The variance within 16 km2 and 100 km2 regions is a linear function of the average slope in the region, suggesting a possible parameterization for sub-grid cell variability.

  10. The topographic distribution of annual incoming solar radiation in the Rio Grande River basin

    SciTech Connect

    Dubayah, R.; Van Katwijk, V. USDA, Hydrology Lab., Beltsville, MD )

    1992-11-01

    We model the annual incoming solar radiation topoclimatology for the Rio Grande River basin in Colorado, U.S.A. Hourly pyranometer measurements are combined with satellite reflectance data and 30-m digital elevation models within a topographic solar radiation algorithm. Our results show that there is large spatial variability within the basin, even at an annual integration length, but the annual, basin-wide mean is close to that measured by the pyranometers. The variance within 16 sq km and 100 sq km regions is a linear function of the average slope in the region, suggesting a possible parameterization for sub-grid-cell variability. 13 refs.

  11. The topographic distribution of annual incoming solar radiation in the Rio Grande River basin

    NASA Technical Reports Server (NTRS)

    Dubayah, R.; Van Katwijk, V.

    1992-01-01

    We model the annual incoming solar radiation topoclimatology for the Rio Grande River basin in Colorado, U.S.A. Hourly pyranometer measurements are combined with satellite reflectance data and 30-m digital elevation models within a topographic solar radiation algorithm. Our results show that there is large spatial variability within the basin, even at an annual integration length, but the annual, basin-wide mean is close to that measured by the pyranometers. The variance within 16 sq km and 100 sq km regions is a linear function of the average slope in the region, suggesting a possible parameterization for sub-grid-cell variability.

  12. Processing of polymer surfaces by laser radiation

    NASA Astrophysics Data System (ADS)

    Kreutz, E. W.; Frerichs, H.; Stricker, J.; Wesner, D. A.

    1995-11-01

    The processing of polymer surfaces by laser radiation is investigated as a function of laser parameters (fluence, mode of operation) and processing variables (repetition rate, pulse number). Polymers under investigation are polyamide, polymethylmethacrylate, polypropylene, polystyrene, polycarbonate, acrylonitrile-butadiene-styrene copolymer, styrene-acrylonitrile copolymer, polybutadiene terephtalate, and polyoxymethylene, which are studied in air within different processing regimes such as modification of surface properties for subsequent metallization and removal of material for structuring of surface geometry. The metallization of polymers, which are pretreated by laser irradiation, wet chemical etching or plasma etching, is performed via electroplating and physical vapour deposition as a function of surface properties. The removal of polymers including non-thermal and thermal processes is done by direct processing techniques in the demagnification mode within one processing step. The diagnosis and the modelling of physical processes involved in tailoring the surface properties of polymers with laser radiation have to be implied to improve any application of these materials.

  13. Radiation exposures for DOE contractor employees-1988. Twenty-first annual report

    SciTech Connect

    Merwin, S. E.; Millet, W. H.; Traub, R. J.

    1990-12-01

    This report is one of a series of annual reports provided by the U.S. Department of Energy (DOE) summarizing occupational radiation exposures received by DOE and DOE contractor employees. These reports provide an overview of radiation exposures received each year and identify trends in exposures being experienced over the years.

  14. Radiation Exposures for DOE and DOE Contractor Employees - 1989. Twenty-second annual report

    SciTech Connect

    Smith, M. H.; Eschbach, P. A.; Harty, R.; Millet, W. H.; Scholes, V. A.

    1992-12-01

    This report is one of a series of annual reports provided by the U.S. Department of Energy (DOE) summarizing occupational radiation exposures received by DOE and DOE contractor employees. These reports provide an overview of radiation exposures received each year and identify trends in exposures being experienced over the years.

  15. Radiation resistence of microorganisms from radiation sterilization processing environments

    NASA Astrophysics Data System (ADS)

    Sabovljev, Svetlana A.; Žunić, Zora S.

    The radiation resistance of microorganisms was examined on the samples of dust collected from the radiation sterilization processing environments including assembly, storage, and sterilization plant areas. The isolation of radiation resistant strains was performed by irradiation with screening doses ranging from 10 to 35 kGy and test pieces containing 10 6 to 10 8 CFU in dried serum-broth, representing 100 to 5000 colonies of primary cultures of microorganisms from 7 different sites. In an examination of 16900 colonies of aerobic microorganisms from 3 hygienically controlled production sites and 4 uncontrolled ones, 30 strains of bacteria were isolated. Of those 15 were classified as genus Bacillus, 9 as Micrococcus and 6 as Sarcina. All of the 15 strains of Gram positive sporeforming aerobic rods exhibited an exponential decrease in the surviving fraction as a function of dose, indicating that the inactivation of spores of aerobic rods is a consequence of a single energy deposition into the target. All strains were found to be moderately resistant to radiation with D-6 values (dose required to reduce survival to 6 log cycles) between 18 and 26 kGy. All of the isolated Gram positive cocci showed inactivation curves having a shoulder, indicating that different processes are involved in the inactivation of these cells, e.g. accumulation of sublethal lesions, or final repair capacity of potential lethal lesions. Moderate radiation resistance was observed in 13 strains with D-6 values between 16 to 30 kGy. Two slow-growing, red pigmented strains tentatively classified as genus Micrococcus isolated from uncontrolled sites (human dwellings) were exceptionally resistant with D-6 more than 45 kGy. For hygienically controlled sites, Gram positive spereforming rods composed two thirds of the resistant microflora, while Gram positive cocci comprised one third. For hygienically uncontrolled sites this ratio was reversed. An assumption is made that one isolated strain has grown

  16. Benefits of radiation processing to public health

    NASA Astrophysics Data System (ADS)

    Kampelmacher, E. H.

    The problem of foodborne diseases, in which especially food of animals origin and the infected animal is involved, is reviewed. Salmonella and Campylobacter contamination of meat and poultry may today, together with parasites in meat and fish be considered as an increasing public health problem. Control and prevention measures, especially including radiation processing is summarized and with regard to specific micro-organisms and parasites and to various food commodities suitable for irradiation purposes. The possibilities of this new processing technique for reduction and probably elimination of pathogens and parasites are discussed and recommendations are given for practical application of radiation in order to eliminate health risks eliminating from contaminated food.

  17. Radiation exposures for DOE and DOE contractor employees - 1991. Twenty-fourth annual report

    SciTech Connect

    Smith, M.H.; Hui, T.E.; Millet, W.H.; Scholes, V.A.

    1994-11-01

    This is the 24th annual radiation exposure report published by US DOE and its predecessor agencies. This report summarizes the radiation exposures received by both employees and visitors at DOE and COE contractor facilities during 1991. Trends in radiations exposures are evaluated. The significance of the doses is addressed by comparing them to the DOE limits and by correlating the doses to health risks based on risk estimates from expert groups.

  18. Radiative processes and non-equilibrium thermodynamics

    NASA Astrophysics Data System (ADS)

    Callies, U.; Herbert, F.

    1988-03-01

    With the assumption of an elementary physical concept meteorologically effective radiative processes (absorption-emission, scattering) can be included consistently in nonequilibrium thermodynamics of irreversible phenomena. Analogously to the usual Gibbs relations a fundamental equation was formulated for monochromatic light rays as the nucleus of the theory. Using the methods of classical irreversible theory, a complete entropy balance equation is derived in which the entropy variations of the mass as well as of the radiation field are explicitly represented. The resulting entropy source strength function σ through its analytical structure reveals the dynamical character of the irreversible variation terms. The σ-expression being positive according to the second law of thermodynamics is found to have a bilinear form as a function of the irreversible fluxes representing the entropy generating radiative processes and their conjugated thermodynamic forces. The mathematical structure and the positive sign of σ, following the usual line of reasoning, motivate the assumption of constitutive relations for the irreversible radiative processes. These equations developed from purely thermodynamical reasoning turn out to be equivalent to the usual radiative transfer equation which is founded on a very different theoretical concept. A very fundamental relationship can be deduced in this context from the entropy production function. It provides a direct thermodynamical proof that in nonscattering media the definition of a local temperature is necessarily accompanied by the validity of the Kirchhoff law.

  19. Microwave processing of ceramic oxide filaments. Annual report, FY1997

    SciTech Connect

    Vogt, G.J.

    1998-12-31

    The objective of the microwave filament processing project is to develop microwave techniques to manufacture continuous ceramic oxide filaments. Microwave processing uses the volumetric absorption of microwave power in oxide filament tows to drive off process solvents, to burn out organic binders, and to sinter the dried fibers to produce flexible, high-strength ceramic filaments. The technical goal is to advance filament processing technology by microwave heating more rapidly with less energy and at a lower cost than conventional processing, but with the same quality as conventional processing. The manufacturing goal is to collaborate with the 3M Company, a US manufacturer of ceramic oxide filaments, to evaluate the technology using a prototype filament system and to transfer the microwave technology to the 3M Company. Continuous ceramic filaments are a principal component in many advanced high temperature materials like continuous fiber ceramic composites (CFCC) and woven ceramic textiles. The use of continuous ceramic filaments in CFCC radiant burners, gas turbines, waste incineration, and hot gas filters in U.S. industry and power generation is estimated to save at least 2.16 quad/yr by year 2010 with energy cost savings of at least $8.1 billion. By year 2010, continuous ceramic filaments and CFCC`s have the potential to abate pollution emissions by 917,000 tons annually of nitrous oxide and 118 million tons annually of carbon dioxide (DOE Report OR-2002, February, 1994).

  20. ANNUAL REPORT. RADIATION EFFECTS IN NUCLEAR WASTE MATERIALS

    EPA Science Inventory

    The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics. This study will provide the underpinning science to develop improved gl...

  1. The importance of the diurnal and annual cycle of air traffic for contrail radiative forcing

    NASA Astrophysics Data System (ADS)

    Stuber, Nicola; Forster, Piers; Rädel, Gaby; Shine, Keith

    2006-06-01

    Air traffic condensation trails, or contrails, are believed to have a net atmospheric warming effect, although one that is currently small compared to that induced by other sources of human emissions. However, the comparably large growth rate of air traffic requires an improved understanding of the resulting impact of aircraft radiative forcing on climate. Contrails have an effect on the Earth's energy balance similar to that of high thin ice clouds. Their trapping of outgoing longwave radiation emitted by the Earth and atmosphere (positive radiative forcing) is partly compensated by their reflection of incoming solar radiation (negative radiative forcing). On average, the longwave effect dominates and the net contrail radiative forcing is believed to be positive. Over daily and annual timescales, varying levels of air traffic, meteorological conditions, and solar insolation influence the net forcing effect of contrails. Here we determine the factors most important for contrail climate forcing using a sophisticated radiative transfer model for a site in southeast England, located in the entrance to the North Atlantic flight corridor. We find that night-time flights during winter (December to February) are responsible for most of the contrail radiative forcing. Night flights account for only 25 per cent of daily air traffic, but contribute 60 to 80 per cent of the contrail forcing. Further, winter flights account for only 22 per cent of annual air traffic, but contribute half of the annual mean forcing. These results suggest that flight rescheduling could help to minimize the climate impact of aviation.

  2. The importance of the diurnal and annual cycle of air traffic for contrail radiative forcing.

    PubMed

    Stuber, Nicola; Forster, Piers; Rädel, Gaby; Shine, Keith

    2006-06-15

    Air traffic condensation trails, or contrails, are believed to have a net atmospheric warming effect, although one that is currently small compared to that induced by other sources of human emissions. However, the comparably large growth rate of air traffic requires an improved understanding of the resulting impact of aircraft radiative forcing on climate. Contrails have an effect on the Earth's energy balance similar to that of high thin ice clouds. Their trapping of outgoing longwave radiation emitted by the Earth and atmosphere (positive radiative forcing) is partly compensated by their reflection of incoming solar radiation (negative radiative forcing). On average, the longwave effect dominates and the net contrail radiative forcing is believed to be positive. Over daily and annual timescales, varying levels of air traffic, meteorological conditions, and solar insolation influence the net forcing effect of contrails. Here we determine the factors most important for contrail climate forcing using a sophisticated radiative transfer model for a site in southeast England, located in the entrance to the North Atlantic flight corridor. We find that night-time flights during winter (December to February) are responsible for most of the contrail radiative forcing. Night flights account for only 25 per cent of daily air traffic, but contribute 60 to 80 per cent of the contrail forcing. Further, winter flights account for only 22 per cent of annual air traffic, but contribute half of the annual mean forcing. These results suggest that flight rescheduling could help to minimize the climate impact of aviation. PMID:16778887

  3. Radiative processes of uniformly accelerated entangled atoms

    NASA Astrophysics Data System (ADS)

    Menezes, G.; Svaiter, N. F.

    2016-05-01

    We study radiative processes of uniformly accelerated entangled atoms, interacting with an electromagnetic field prepared in the Minkowski vacuum state. We discuss the structure of the rate of variation of the atomic energy for two atoms traveling in different hyperbolic world lines. We identify the contributions of vacuum fluctuations and radiation reaction to the generation of entanglement as well as to the decay of entangled states. Our results resemble the situation in which two inertial atoms are coupled individually to two spatially separated cavities at different temperatures. In addition, for equal accelerations we obtain that one of the maximally entangled antisymmetric Bell state is a decoherence-free state.

  4. Atmospheric Radiation Measurement Climate Research Facility (ACRF) Annual Report 2008

    SciTech Connect

    LR Roeder

    2008-12-01

    The Importance of Clouds and Radiation for Climate Change: The Earth’s surface temperature is determined by the balance between incoming solar radiation and thermal (or infrared) radiation emitted by the Earth back to space. Changes in atmospheric composition, including greenhouse gases, clouds, and aerosols, can alter this balance and produce significant climate change. Global climate models (GCMs) are the primary tool for quantifying future climate change; however, there remain significant uncertainties in the GCM treatment of clouds, aerosol, and their effects on the Earth’s energy balance. In 1989, the U.S. Department of Energy (DOE) Office of Science created the Atmospheric Radiation Measurement (ARM) Program to address scientific uncertainties related to global climate change, with a specific focus on the crucial role of clouds and their influence on the transfer of radiation in the atmosphere. To reduce these scientific uncertainties, the ARM Program uses a unique twopronged approach: • The ARM Climate Research Facility, a scientific user facility for obtaining long-term measurements of radiative fluxes, cloud and aerosol properties, and related atmospheric characteristics in diverse climate regimes; and • The ARM Science Program, focused on the analysis of ACRF and other data to address climate science issues associated with clouds, aerosols, and radiation, and to improve GCMs. This report provides an overview of each of these components and a sample of achievements for each in fiscal year (FY) 2008.

  5. Induced radioactivity from industrial radiation processing

    NASA Astrophysics Data System (ADS)

    Lone, M. A.

    1990-12-01

    Analytic expressions are developed for quantitative analysis of radioactivity induced by radiation processing of products with electrons or photons. These expressions provide reasonable estimates of induced activity much faster than Monte Carlo simulations. Analysis of radioactivity from processing of meat with 10 MeV electrons shows an induced activity of less than 10 mBq/(kgkGy) just after irradiation. This is 4 orders of magnitude less than the natural background activity of about 100 Bq/kg found in meat. Five days after processing the induced activity will reduce by a factor of 300.

  6. Genetic variation in resistance to ionizing radiation. [Annual report, 1989

    SciTech Connect

    Ayala, F.J.

    1989-12-31

    The very reactive superoxide anion O{sub 2} is generated during cell respiration as well as during exposure to ionizing radiation. Organisms have evolved different mechanisms to protect against the deleterious effects of reduced oxygen species. The copper-zinc superoxide dismutase is a eukaryotic cytoplasmic enzyme that protects the cell by scavenging superoxide radicals and dismutating them to hydrogen peroxide and molecular oxygen: 20{sub 2}{sup {minus}} + 2H {yields} H{sub 2}O{sub 2} + O{sub 2}. SOD had been shown to protect against ionizing radiation damage to DNA, viruses, bacteria, mammalian cells, whole mice, and Drosophila. Evidence that genetic differences may affect sensitivity to ionizing radiation has been shown in Drosophila since differences have been shown to exist between strains and resistance to radiation can evolve under natural selection.

  7. ADVANCED RADIATION THEORY SUPPORT ANNUAL REPORT 2002, FINAL REPORT

    SciTech Connect

    J. DAVIS; J. APRUZESE; , Y. CHONG; R. CLARK; A. DASGUPTA; J. GIULIANI; P. KEPPLE; R. TERRY; J. THORNHILL; A. VELIKOVICH

    2003-05-01

    Z-PINCH PHYSICS RADIATION FROM WIRE ARRAYS. This report describes the theory support of DTRA's Plasma Radiation Source (PRS) program carried out by NRL's Radiation Hydrodynamics Branch (Code 6720) in FY 2002. Included is work called for in DTRA MIPR 02-2045M - ''Plasma Radiation Theory Support'' and in DOE's Interagency Agreement DE-AI03-02SF22562 - ''Spectroscopic and Plasma Theory Support for Sandia National Laboratories High Energy Density Physics Campaign''. Some of this year's work was presented at the Dense Z-Pinches 5th International Conference held June 23-28 in Albuquerque, New Mexico. A common theme of many of these presentations was a demonstration of the importance of correctly treating the radiation physics for simulating Plasma Radiation Source (PRS) load behavior and diagnosing load properties, e.g, stagnation temperatures and densities. These presentations are published in the AIP Conference Proceedings and, for reference, they are included in Section 1 of this report. Rather than describe each of these papers in the Executive Summary, they refer to the abstracts that accompany each paper. As a testament to the level of involvement and expertise that the Branch brings to DTRA as well as the general Z-Pinch community, eight first-authored presentations were contributed at this conference as well as a Plenary and an Invited Talk. The remaining four sections of this report discuss subjects either not presented at the conference or requiring more space than allotted in the Proceedings.

  8. Annual and interannual variations of absorbed solar radiation based on a 10-year data set

    NASA Technical Reports Server (NTRS)

    Smith, G. Louis; Charlock, Thomas P.; Bess, T. Dale; Rutan, David

    1990-01-01

    Annual and interannual variations of absorbed solar radiation (ASR) are studied using the 10-year earth radiation budget data set from the Nimbus-6 and Nimbus-7 earth radiation budget instruments in the form of monthly averaged maps of ASR. Empirical orthogonal functions (EOFs) are computed for the global distribution of ASR. Six EOFs are found which have physical significance and which account for 97.8 percent of the spatial variance of the data set. The first EOF describes the annual cycle and is primarily a latitudinal variation which is driven by the incident solar radiation. The second and fourth EOFs are semiannual cycles. EOFs 3 through 6 are strongly longitudinally dependent. EOF 3 describes the spring/fall part of the annual cycle, and EOF 4 describes the part of the semiannual cycle which is out of phase with EOF 2. EOF 5 is the response of the ASR to El Nino. The annual cycle and its harmonics account for 97.6 percent of the variance with time. When the data set is deseasonalized, the first two EOFs of the resulting set are found to correspond closely to EOFs 5 and 6 of the data set with season included. As with outgoing longwave radiation, most of the interannual variation is found over the tropical oceans.

  9. Innovative machine designs for radiation processing

    NASA Astrophysics Data System (ADS)

    Vroom, David

    2007-12-01

    In the 1990s Raychem Corporation established a program to investigate the commercialization of several promising applications involving the combined use of its core competencies in materials science, radiation chemistry and e-beam radiation technology. The applications investigated included those that would extend Raychem's well known heat recoverable polymer and wire and cable product lines as well as new potential applications such as remediation of contaminated aqueous streams. A central part of the program was the development of new accelerator technology designed to improve quality, lower processing costs and efficiently process conformable materials such at liquids. A major emphasis with this new irradiation technology was to look at the accelerator and product handling systems as one integrated, not as two complimentary systems.

  10. Heat pump processes induced by laser radiation

    NASA Technical Reports Server (NTRS)

    Garbuny, M.; Henningsen, T.

    1980-01-01

    A carbon dioxide laser system was constructed for the demonstration of heat pump processes induced by laser radiation. The system consisted of a frequency doubling stage, a gas reaction cell with its vacuum and high purity gas supply system, and provisions to measure the temperature changes by pressure, or alternatively, by density changes. The theoretical considerations for the choice of designs and components are dicussed.

  11. Fast dynamic processes of solar radiation

    SciTech Connect

    Tomson, Teolan

    2010-02-15

    This paper studies dynamic processes of fast-alternating solar radiation which are assessed by alternation of clouds. Most attention is devoted to clouds of type Cumulus Humilis, identified through visual recognition and/or a specially constructed automatic sensor. One second sampling period was used. Recorded data series were analyzed with regard to duration of illuminated 'windows' between shadows, their stochastic intervals, fronts and the magnitude of increments of solar irradiance. (author)

  12. Diffusion processes in general relativistic radiating spheres

    SciTech Connect

    Barreto, W.; Herrera, L.; Santos, N.O.; Universidad Central de Venezuela, Caracas; Observatorio Nacional do Brasil, Rio de Janeiro )

    1989-09-01

    The influence of diffusion processes on the dynamics of general relativistic radiating spheres is systematically studied by means of two examples. Differences between the streaming-out limit and the diffusion limit are exhibited, for both models, through the evolution curves of dynamical variables. In particular it is shown the Bondi mass decreases, for both models, in the diffusion limit as compared with its value at the streaming-out regime. 15 refs.

  13. Radiation and Photochemistry Section annual report, October 1991--September 1992

    SciTech Connect

    Not Available

    1992-11-01

    A survey is presented of research on reactive intermediates in the condensed phase and chemistry induced by energetic radiation. The survey is presented in two major parts: (1) ions, excited states, and other transients in condensed phase; and (2) role of solvents in chemical reactivity. Accelerator activities (20-MeV linac, 3-MeV Van de Graaff) are summarized.

  14. Public relations and the radiation processing industry

    NASA Astrophysics Data System (ADS)

    Coates, T. Donna

    The world's uneasiness and mistrust regarding anything nuclear has heightened in recent years due to events such as Chernobyl and Three Mile Island. Opinion polls and attitude surveys document the public's growing concern about issues such as the depletion of the ozone layer, the resulting greenhouse effect and exposure of our planet to cosmic radiation. Ultimately, such research reveals an underlying fear regarding the unseen impacts of modern technology on the environment and on human health. These concerns have obvious implications for the radiation processing industry, whose technology is nuclear based and not easily understood by the public. We have already seen organized nuclear opponents mobilize public anxiety, fear and misunderstanding in order to oppose the installation of radiation processing facilities and applications such as food irradiation. These opponents will no doubt try to strengthen resistance to our technology in the future. Opponents will attempt to convince the public that the risks to public and personal health and safety outweigh the benefits of our technology. We in the industry must head off any tendency for the public to see us as the "enemy". Our challenge is to counter public uneasiness and misunderstanding by effectively communicating the human benefits of our technology. Clearly it is a challenge we cannot afford to ignore.

  15. NREL Solar Radiation Resource Assessment Project: Status and outlook. Annual progress report, FY 1992

    SciTech Connect

    Renne, D.; Maxwell, E.; Stoffel, T.; Marion, B.; Rymes, M.; Wilcox, S.; Myers, D.; Riordan, C.; Hammond, E.; Ismailidis, T.

    1993-06-01

    This annual report summaries the activities and accomplishments of the Solar Radiation Resource Assessment Project during fiscal year 1992 (1 October to 30 September 1992). Managed by the Analytic Studies Division of the National Renewable Energy Laboratory, this project is the major activity of the US Department of Energy`s Resource Assessment Program.

  16. Processes linking the hydrological cycle and the atmospheric radiative budget

    NASA Astrophysics Data System (ADS)

    Fueglistaler, Stephan; Dinh, Tra

    2016-04-01

    We study the response of the strength of the global hydrological cycle to changes in carbon dioxide (CO2) using the HiRAM General Circulation Model developed at the Geophysical Fluid Dynamics Laboratory (GFDL), with the objective to better connect the well-known energetic constraints to physical processes. We find that idealized model setups using a global slab ocean and annual mean insolation give similar scalings as coupled atmosphere-ocean models with realistic land and topography. Using the surface temperatures from the slab ocean runs, we analyse the response in the atmospheric state and hydrological cycle separately for a change in CO2 (but fixed surface temperature), and for a change in surface temperature (but fixed CO2). The former perturbation is also referred to as the "fast" response, whereas the latter is commonly used to diagnose a model's climate sensitivity. As expected from the perspective of the atmospheric radiative budget, an increase in CO2 at fixed surface temperature decreases the strength of the hydrological cycle, and an increase in surface temperature increases the strength of the hydrological cycle. However, the physical processes that connect the atmospheric radiative energy budget to the sensible and latent heat fluxes at the surface remain not well understood. The responses to the two perturbations are linearly additive, and we find that the experiment with fixed surface temperature and changes in CO2 is of great relevance to understanding the total response. This result points to the importance of local radiative heating rate changes rather than just the net atmospheric radiative loss of energy. Although larger in magnitude, the response to changes in surface temperature is dominated by the temperature dependence of the water vapor pressure, but in both cases changes in near-surface relative humidity are very important.

  17. Evaluation of 20-min and Annual Radiation Budget Components and Cloudiness in a Mountainous Valley

    NASA Astrophysics Data System (ADS)

    Malek, E.

    2007-05-01

    Logan, Utah (USA) is among cities located in the mountainous valley in the western portion of Rocky Mountains in North America. It is the county seat of Cache Valley, a metropolitan area with a population of about 100,000. The valley had the polluted air in the USA during January 2004. To evaluate the daily and annual radiation budget and cloudiness in this mountainous valley, we set up a radiation station in the middle of the valley to measure the 20- min radiation budget components namely: incoming (Rso) and outgoing (Rso) solar or shortwave radiation, using to CM21 Kipp and Zonen (one inverted) and incoming (Rli) (or atmospheric) and outgoing (Rlo) or terrestrial) longwave radiation using two CG1 Kipp and Zonen Pyrgeometers (one inverted) during the year of 2003. All pyranometers and Pyrgeometers were ventilated with four CV2 Kipp and Zonen ventilation systems throughout the year to prevent deposition of dew, frost and snow, which otherwise would disturb the measurements. We also measured the 2-m air temperature and relative humidity along with surface temperature. All measurements were taken every 2 s, averaged to 20 min, continuously throughout the year 2000. A Met One heated rain gauge measured precipitation. Comparison of the annual radiation budget components indicates that about 25% of the annual Rsi (5848.6 MJ/ (squared m-y)) was reflected back to sky as Rso. Rli and Rlo amounted to 9968.7 and 13303.5 MJ/ (squared m-y)), respectively. This yielded about 1364.9 MJ/ (squared m- y)) available energy (Rn). Having the 2-m air temperature and moisture data and comparison between the theoretical and the measured longwave radiation, we evaluated the 20-m cloudy conditions throughout the year of 2003. The average cloud base height was 587 m (ranged from zero for foggy conditions to about 3000 m). Annual cloudiness contributed about 139.1 MJ/ (squared m-y)) more energy in this valley.

  18. Atmospheric Radiation Measurement Climate Research Facility Annual Report 2006

    SciTech Connect

    LR Roeder

    2005-11-30

    This annual report describes the purpose and structure of the ARM Climate Research Facility and ARM Science programs and presents key accomplishments in 2006. Noteworthy scientific and infrastructure accomplishments in 2006 include: • Collaborating with the Australian Bureau of Meteorology to lead the Tropical Warm Pool-International Cloud Experiment, a major international field campaign held in Darwin, Australia • Successfully deploying the ARM Mobile Facility in Niger, Africa • Developing the new ARM Aerial Vehicles Program (AVP) to provide airborne measurements • Publishing a new finding on the impacts of aerosols on surface energy budget in polar latitudes • Mitigating a long-standing double-Intertropical Convergence Zone problem in climate models using ARM data and a new cumulus parameterization scheme.

  19. Factors determining the viability of radiation processing in developing countries

    NASA Astrophysics Data System (ADS)

    van der Linde, HJ; Basson, RA

    In the fifteen years since the introduction of radiation processing to South Africa, four commercial irradiation facilities have been established. These are involved in the processing of a large variety of products, from syringes and prostheses to strawberries and sugar yeast. Three of the facilities are devoted mainly to food irradiation and several thousand tonnes are now processed annually. During this period it was repeatedly experienced that the successful introduction of radiation processing in general, and food radurization in particular, on a commercial scale was critically dependent on the following factors: acceptance by the producer, industry and consumer; initial capital expenditure; running costs and overheads in general; and continous throughput. All of these factors contribute to the processing cost which is the ultimate factor in determing the value/price ratio for the potential entrepreneur and customer of this new technology. After a market survey had identified the need for a new food irradiation facility to cope with the growing interest in commercial food radurization in the Western Cape, the above-mentioned factors were of cardinal importance in the design and manufacture of a new irradiator. The resulting batch-pallet facility which was commisioned in August 1986, is rather inefficient as far as energy utilization is concerned but this shortcoming is compensated for by its low cost, versatility and low hold-up. Although the facility has limitations as far as the processing of really large volumes of produce is concerned, it is particularly suitable not only for developing countries, but for developed countries in the introductory phase of commercial food radurization.

  20. Annual cycle and spatial spectra of earth emitted radiation at large scales

    NASA Technical Reports Server (NTRS)

    Smith, G. L.; Bess, T. D.

    1983-01-01

    Monthly averaged, resolution enhanced global distributions of the earth's emitted radiation, as measured by the Nimbus-6 Earth Radiation Budget (ERB) wide field of view radiometers, have been analyzed for 1 year of data from July 1975 to June 1976. These distributions are expressed in terms of spherical harmonic coefficients, and time and space variability of the emitted radiation field is studied in terms of these coefficients. The average annual distribution accounts for 78 percent of the space-time power, and the annual cycle accounts for 17 percent of the power. Spatial variations over the globe are described in terms of degree variance, and longitudinal variations are described in terms of spectral power as a function of latitude. The longitudinal spectra were found to vary strongly with time.

  1. Annual cycle of radiation fluxes over the Arctic ocean: Sensitivity to cloud optical properties

    SciTech Connect

    Curry, J.A. ); Ebert, E.E. )

    1992-11-01

    The relationship between cloud optical properties and the radiative fluxes over the Arctic Ocean is explored by conducting a series of modeling experiments. The annual cycle of arctic cloud optical properties that are required to reproduce both the outgoing radiative fluxes at the top of the atmosphere as determined from satellite observations and the available determinations of surface radiative fluxes are derived. Existing data on cloud fraction and cloud microphysical properties are utilized. Four types of cloud are considered: low stratus clouds, midlevel clouds, citrus clouds, and wintertime ice crystal precipitation. Internally consistent annual cycles of surface temperature, surface albedo, cloud fraction and cloud optical properties, components of surface and top of atmosphere radiative fluxes, and cloud radiative forcing are presented. The modeled total cloud optical depth (weighted by cloud fraction) ranges from a low value in winter of 2 to a high summertime value of 8. Infrared emmissivities for liquid water clouds are shown to be substantially less than unity during the cold half of the year. Values of modeled surface cloud radiative forcing are positive except for two weeks in midsummer; over the course of the year clouds have a net warming effect on the surface in the Arctic. Total cloud radiative forcing at the top of the atmosphere is determined to be positive only briefly in early autumn. Surface longwave fluxes are shown to be very sensitive to the presence of lower-tropospheric ice crystal precipitation during the cold half of the year.

  2. Processing circuitry for single channel radiation detector

    NASA Technical Reports Server (NTRS)

    Holland, Samuel D. (Inventor); Delaune, Paul B. (Inventor); Turner, Kathryn M. (Inventor)

    2009-01-01

    Processing circuitry is provided for a high voltage operated radiation detector. An event detector utilizes a comparator configured to produce an event signal based on a leading edge threshold value. A preferred event detector does not produce another event signal until a trailing edge threshold value is satisfied. The event signal can be utilized for counting the number of particle hits and also for controlling data collection operation for a peak detect circuit and timer. The leading edge threshold value is programmable such that it can be reprogrammed by a remote computer. A digital high voltage control is preferably operable to monitor and adjust high voltage for the detector.

  3. 27th Annual national conference on radiation control

    SciTech Connect

    1995-12-31

    A wide variety of topics related to radiation control are presented in the 21 papers selected for the database. Topics covered include: radioactive soil cleanup standards, low-level radioactive waste, Licensing State Designation program, health physics, radioactive contamination of scrap metal, radioactive contamination of food, U.S. Nuclear Regulatory Commission materials licensing program, high and pulsed dose rate medical therapy, licensing of a commercial mixed waste facility, radioactive sewer discharge regulations, air emission standards for radionuclides, and regulation of naturally occurring radioactive materials in oil and gas fields. Other topics covered, but not selected for the database, are primarily related to medical x-ray programs.

  4. Cloud contribution to the daily and annual radiation budget in a mountainous valley

    NASA Astrophysics Data System (ADS)

    Malek, Esmaiel

    An automated-ventilated radiation station has been set up in a mountainous valley at the Logan Airport in northern Utah, USA, since mid-1995, to evaluate the daily and annual radiation budget components, and develop an algorithm to study cloudiness and its contribution to the daily and annual radiation. This radiation station (composed of pyranometers, pyrgeometers and a net radiometer) provides continuous measurements of downward and upward shortwave, longwave and net radiation throughout the year. The surface temperature and pressure, the 2-m air temperature and humidity, precipitation, and wind at this station were also measured. A heated rain gauge provided precipitation information. Using air temperature and moisture and measured downward longwave (atmospheric) radiation, appropriate formula (among four approaches) was chosen for computation of cloudless-skies atmospheric emissivity. Considering the additional longwave radiation during the cloudy skies coming from the cloud in the waveband which the gaseous emission lacks (from 8-13 μm), an algorithm was developed which provides continuous 20-min cloud information (cloud base height, cloud base temperature, percent of skies covered by cloud, and cloud contribution to the radiation budget) over the area during day and night. On the partly-cloudy day of 3 February, 2003, for instance, cloud contributed 1.34 MJ m - 2 d - 1 out of 26.92 MJ m - 2 d - 1 to the daily atmospheric radiation. On the overcast day of 18 December, 2003, this contribution was 5.77 MJ m - 2 d - 1 out of 29.38 MJ m - 2 d - 1 . The same contribution for the year 2003 amounted to 402.85 MJ m - 2 y - 1 out of 9976.08 MJ m - 2 y - 1 . Observations (fog which yielded a zero cloud base height and satellite cloud imaging data) throughout the year confirmed the validity of the computed data. The nearby Bowen ratio station provided the downward radiation and net radiation data. If necessary, these data could be substituted for the missing data at the

  5. Radiative processes in external gravitational fields

    SciTech Connect

    Papini, Giorgio

    2010-07-15

    Kinematically forbidden processes may be allowed in the presence of external gravitational fields. These can be taken into account by introducing generalized particle momenta. The corresponding transition probabilities can then be calculated to all orders in the metric deviation from the field-free expressions by simply replacing the particle momenta with their generalized counterparts. The procedure applies to particles of any spin and to any gravitational fields. Transition probabilities, emission power, and spectra are, to leading order, linear in the metric deviation. It is also shown how a small dissipation term in the particle wave equations can trigger a strong backreaction that introduces resonances in the radiative process and deeply affects the resulting gravitational background.

  6. Radiation and Photochemistry Section annual report, October 1992--November 1993

    SciTech Connect

    1993-11-01

    The research described in this survey is a study of transient intermediates and chemistry induced by energetic radiation in the condensed phase. The survey is presented in two major parts: the first one studies ions, excited states, and other transients in the condensed phase; the second one studies the role of solvents in chemical reactivity. Some highlights of the past year were observations of ion-molecule reactions of excited aromatic cations via flash photolysis and transient dc conductivity; anion solvation study revealing role of solvent molecular structure; zeolite matrix study of C{sub 7}H{sub 8} radical cation chemistry; and H atom reaction with O{sub 2}, I{sup {minus}}, and comparison of diffusion of H, D, and muonium in ice. Refs, 25 figs, 5 tabs.

  7. Radiation processing with the Messina electron linac

    NASA Astrophysics Data System (ADS)

    Auditore, L.; Barnà, R. C.; De Pasquale, D.; Emanuele, U.; Loria, D.; Morgana, E.; Trifirò, A.; Trimarchi, M.

    2008-05-01

    In the last decades radiation processing has been more and more applied in several fields of industrial treatments and scientific research as a safe, reliable and economic technique. In order to improve existing industrial techniques and to develop new applications of this technology, at the Physics Department of Messina University a high power 5 MeV electron linac has been studied and set-up. The main features of the accelerating structure will be described together with the distinctive features of the delivered beam and several results obtained by electron beam irradiations, such as improvement of the characteristics of polymers and polymer composite materials, synthesis of new hydrogels for pharmaceutical and biomedical applications, reclaim of culture ground, sterilization of medical devices, development of new dosimeters for very high doses and dose rates required for monitoring of industrial irradiations.

  8. Estimation of annual occupational effective doses from external ionizing radiation at medical institutions in Kenya

    NASA Astrophysics Data System (ADS)

    Korir, Geoffrey; Wambani, Jeska; Korir, Ian

    2011-04-01

    This study details the distribution and trends of doses due to occupational radiation exposure among radiation workers from participating medical institutions in Kenya, where monthly dose measurements were collected for a period of one year ranging from January to December in 2007. A total of 367 medical radiation workers were monitored using thermoluminescent dosemeters. They included radiologists (27%), oncologists (2%), dentists (4%), Physicists (5%), technologists (45%), nurses (4%), film processor technicians (3%), auxiliary staff (4%), and radiology office staff (5%). The average annual effective dose of all categories of staff was found to range from 1.19 to 2.52 mSv. This study formed the initiation stage of wider, comprehensive and more frequent monitoring of occupational radiation exposures and long-term investigations into its accumulation patterns in our country.

  9. Nonthermal Radiation Processes in Interplanetary Plasmas

    NASA Astrophysics Data System (ADS)

    Chian, A. C. L.

    1990-11-01

    RESUMEN. En la interacci6n de haces de electrones energeticos con plasmas interplanetarios, se excitan ondas intensas de Langmuir debido a inestabilidad del haz de plasma. Las ondas Langmuir a su vez interaccio nan con fluctuaciones de densidad de baja frecuencia para producir radiaciones. Si la longitud de las ondas de Langmujr exceden las condicio nes del umbral, se puede efectuar la conversi5n de modo no lineal a on- das electromagneticas a traves de inestabilidades parametricas. As se puede excitar en un plasma inestabilidades parametricas electromagneticas impulsadas por ondas intensas de Langmuir: (1) inestabilidades de decaimiento/fusi5n electromagnetica impulsadas por una bomba de Lang- muir que viaja; (2) inestabilidades dobles electromagneticas de decai- miento/fusi5n impulsadas por dos bombas de Langrnuir directamente opues- tas; y (3) inestabilidades de dos corrientes oscilatorias electromagne- ticas impulsadas por dos bombas de Langmuir de corrientes contrarias. Se concluye que las inestabilidades parametricas electromagneticas in- ducidas por las ondas de Langmuir son las fuentes posibles de radiacio- nes no termicas en plasmas interplanetarios. ABSTRACT: Nonthermal radio emissions near the local electron plasma frequency have been detected in various regions of interplanetary plasmas: solar wind, upstream of planetary bow shock, and heliopause. Energetic electron beams accelerated by solar flares, planetary bow shocks, and the terminal shock of heliosphere provide the energy source for these radio emissions. Thus, it is expected that similar nonthermal radiation processes may be responsible for the generation of these radio emissions. As energetic electron beams interact with interplanetary plasmas, intense Langmuir waves are excited due to a beam-plasma instability. The Langmuir waves then interact with low-frequency density fluctuations to produce radiations near the local electron plasma frequency. If Langmuir waves are of sufficiently large

  10. Committee on Interagency Radiation Research and Policy Coordination. Fourth annual report, July 1, 1987--June 30, 1988

    SciTech Connect

    Young, A.L.

    1988-06-30

    This is the fourth annual report of the Committee on Interagency Radiation Research and Policy Coordination (CIRRPC). CIRRPC was chartered April 9, 1984 under the Federal Coordinating Council for Science, Engineering and Technology (FCCSET) and reports to the Office of Science and Technology Policy (OSTP), Executive Office of the President. Its overall charge is to coordinate radiation matters between agencies, evaluate radiation research, and provide advice on the formulation of radiation policy.

  11. Radiation exposures for DOE and DOE contractor employees, 1990. Twenty-third annual report

    SciTech Connect

    Smith, M.H.; Hui, T.E.; Millet, W.H.; Scholes, V.A.

    1994-03-01

    This is the 23rd in a series of annual radiation exposure reports published by the Department of Energy (DOE) or its predecessors. This report summarizes the radiation exposures received by both employees and visitors at DOE and DOE contractor facilities during 1990. Trends in radiation exposures are evaluated by comparing the doses received in 1990 to those received in previous years. The significance of the doses is addressed by comparing them to the DOE limits and by correlating the doses to health risks based on risk estimated from expert groups. This report is the third that is based on detailed exposure data for each individual monitored at a DOE facility. Prior to 1988, only summarized data from each facility were available. This report contains information on different types of radiation doses, including total effective, internal, penetrating, shallow, neutron, and extremity doses. It also contains analysis of exposures by age, sex, and occupation of the exposed individuals. This report also continues the precedent established in the Twenty-First (1988) Annual Report by conducting a detailed, one-time review and analysis of a particular topic of interest. The special topic for this report is a comparison of total effective, internal, and extremity dose equivalent values against penetrating dose equivalent values.

  12. Radiation processing and functional properties of soybean ( Glycine max)

    NASA Astrophysics Data System (ADS)

    Pednekar, Mrinal; Das, Amit K.; Rajalakshmi, V.; Sharma, Arun

    2010-04-01

    Effect of radiation processing (10, 20 and 30 kGy) on soybean for better utilization was studied. Radiation processing reduced the cooking time of soybean and increased the oil absorption capacity of soy flour without affecting its proximate composition. Irradiation improved the functional properties like solubility, emulsification activity and foam stability of soybean protein isolate. The value addition effect of radiation processing has been discussed for the products (soy milk, tofu and tofu fortified patties) prepared from soybean.

  13. Radiation processing of minimally processed vegetables and aromatic plants

    NASA Astrophysics Data System (ADS)

    Trigo, M. J.; Sousa, M. B.; Sapata, M. M.; Ferreira, A.; Curado, T.; Andrada, L.; Botelho, M. L.; Veloso, M. G.

    2009-07-01

    Vegetables are an essential part of people's diet all around the world. Due to cultivate techniques and handling after harvest, these products, may contain high microbial load that can cause food borne outbreaks. The irradiation of minimally processed vegetables is an efficient way to reduce the level of microorganisms and to inhibit parasites, helping a safe global trade. Evaluation of the irradiation's effects was carried out in minimal processed vegetables, as coriander ( Coriandrum sativum L .), mint ( Mentha spicata L.), parsley ( Petroselinum crispum Mill, (A.W. Hill)), lettuce ( Lactuca sativa L.) and watercress ( Nasturium officinale L.). The inactivation level of natural microbiota and the D 10 values of Escherichia coli O157:H7 and Listeria innocua in these products were determined. The physical-chemical and sensorial characteristics before and after irradiation at a range of 0.5 up to 2.0 kGy applied doses were also evaluated. No differences were verified in the overall of sensorial and physical properties after irradiation up to 1 kGy, a decrease of natural microbiota was noticed (⩾2 log). Based on the determined D10, the amount of radiation necessary to kill 10 5E. coli and L. innocua was between 0.70 and 1.55 kGy. Shelf life of irradiated coriander, mint and lettuce at 0.5 kGy increased 2, 3 and 4 days, respectively, when compared with non-irradiated.

  14. The annual radiation balance of the earth-atmosphere system during 1969-70 from Nimbus 3 measurements.

    NASA Technical Reports Server (NTRS)

    Raschke, E.; Vonder Haar, T. H.; Bandeen, W. R.; Pasternak , M.

    1973-01-01

    Measurements of reflected solar radiation and emitted thermal radiation taken with a radiometer on the meteorological satellite Nimbus 3 during 10 semi-monthly periods (April-15 August, 3-17 October, 1969; 21 January-3 February, 1970) provided for the first time high-resolution data on the earth's annual global radiation budget. Results on the planetary albedo, the amount of absorbed solar radiation, the infrared radiation loss to space, and the radiation balance of the earth-atmosphere system are discussed at various scales: global, hemispherical, and zonal averages; as well as global and polar maps with a spatial resolution of about synoptic scale.

  15. NATO CCMS PILOT STUDY ON CLEAN PRODUCTS AND PROCESSES -(PHASE I) - 2002 ANNUAL REPORT

    EPA Science Inventory

    The annual report summarizes the activities of the NATO CCMS Pilot Study on clean products and processes for 2002, including the proceedings of the 2002 annual meeting held in Vilnius, Lithuania. The report presents a wealth of information on cleaner production activities in ove...

  16. NATO/CCMS PILOT STUDY - CLEAN PRODUCTS AND PROCESSES (PHASE I) 2000 ANNUAL REPORT, NUMBER 242

    EPA Science Inventory

    This annual report presents the proceedings of the Third Annual NATO/CCMS pilot study meeting in Copenhagen, Denmark. Guest speakers focused on efforts in the area of research of clean products and processes, life cycle analysis, computer tools and pollution prevention.

  17. The role of land-surface processes in modulating the Indian monsoon annual cycle

    NASA Astrophysics Data System (ADS)

    Bollasina, Massimo A.; Ming, Yi

    2013-11-01

    The annual cycle of solar radiation, together with the resulting land-ocean differential heating, is traditionally considered the dominant forcing controlling the northward progression of the Indian monsoon. This study makes use of a state-of-the-art atmospheric general circulation model in a realistic configuration to conduct “perpetual” experiments aimed at providing new insights into the role of land-atmosphere processes in modulating the annual cycle of precipitation over India. The simulations are carried out at three important stages of the monsoon cycle: March, May, and July. Insolation and SSTs are held fixed at their respective monthly mean values, thus eliminating any external seasonal forcing. In the perpetual May experiment both precipitation and circulation are able to considerably evolve only by regional internal land-atmosphere processes and the mediation of soil hydrology. A large-scale equilibrium state is reached after approximately 270 days, closely resembling mid-summer climatological conditions. As a result, despite the absence of external forcing, intense and widespread rains over India are able to develop in the May-like state. The interaction between soil moisture and circulation, modulated by surface heating over the northwestern semi-arid areas, determines a slow northwestward migration of the monsoon, a crucial feature for the existence of desert regions to the west. This also implies that the land-atmosphere system in May is far from being in equilibrium with the external forcing. The inland migration of the precipitation front comprises a succession of large-scale 35-50 day coupled oscillations between soil moisture, precipitation, and circulation. The oscillatory regime is self-sustained and entirely due to the internal dynamics of the system. In contrast to the May case, minor changes in the land-atmosphere system are found when the model is initialized in March and, more surprisingly, in July, the latter case further emphasizing

  18. Processes controlling the annual cycle of Arctic aerosol number and size distributions

    NASA Astrophysics Data System (ADS)

    Croft, Betty; Martin, Randall V.; Leaitch, W. Richard; Tunved, Peter; Breider, Thomas J.; D'Andrea, Stephen D.; Pierce, Jeffrey R.

    2016-03-01

    Measurements at high-Arctic sites (Alert, Nunavut, and Mt. Zeppelin, Svalbard) during the years 2011 to 2013 show a strong and similar annual cycle in aerosol number and size distributions. Each year at both sites, the number of aerosols with diameters larger than 20 nm exhibits a minimum in October and two maxima, one in spring associated with a dominant accumulation mode (particles 100 to 500 nm in diameter) and a second in summer associated with a dominant Aitken mode (particles 20 to 100 nm in diameter). Seasonal-mean aerosol effective diameter from measurements ranges from about 180 in summer to 260 nm in winter. This study interprets these annual cycles with the GEOS-Chem-TOMAS global aerosol microphysics model. Important roles are documented for several processes (new-particle formation, coagulation scavenging in clouds, scavenging by precipitation, and transport) in controlling the annual cycle in Arctic aerosol number and size. Our simulations suggest that coagulation scavenging of interstitial aerosols in clouds by aerosols that have activated to form cloud droplets strongly limits the total number of particles with diameters less than 200 nm throughout the year. We find that the minimum in total particle number in October can be explained by diminishing new-particle formation within the Arctic, limited transport of pollution from lower latitudes, and efficient wet removal. Our simulations indicate that the summertime-dominant Aitken mode is associated with efficient wet removal of accumulation-mode aerosols, which limits the condensation sink for condensable vapours. This in turn promotes new-particle formation and growth. The dominant accumulation mode during spring is associated with build up of transported pollution from outside the Arctic coupled with less-efficient wet-removal processes at colder temperatures. We recommend further attention to the key processes of new-particle formation, interstitial coagulation, and wet removal and their delicate

  19. Guide for preparing annual reports on radiation-safety testing of electronic products (general)

    SciTech Connect

    Not Available

    1987-10-01

    For manufacturers of electronic products other than those for which a specific guide has been issued, the guide replaces the Guide for the Filing of Annual Reports (21 CFR Subchapter J, Section 1002.11), HHS Publication FDA 82-8127. The electronic product (general) annual reporting guide is applicable to the following products: products intended to produce x radiation (accelerators, analytical devices, therapy x-ray machines); microwave diathermy machines; cold-cathode discharge tubes; and vacuum switches and tubes operating at or above 15,000 volts. To carry out its responsibilities under Public Law 90-602, the Food and Drug Administration's Center for Devices and Radiological Health (CDRH) has issued a series of regulations contained in Title 21 of the Code of Federal Regulations (CFR). Part 1002 of 21 CFR deals with records and reports. Section 1002.61 categorizes electronic products into Groups A through C. Section 1002.30 requires manufacturers of products in Groups B and C to establish and maintain certain records, while Section 1002.11 requires such manufacturers to submit an Annual Report summarizing the contents of the required records. Section 1002.7 requires that reports conform to reporting guides issued by CDRH unless an acceptable justification for an alternate format is provided.

  20. Reporting of Uncertainty at the 2013 Annual Meeting of the American Society for Radiation Oncology

    SciTech Connect

    Lee, W. Robert

    2014-05-01

    Purpose: The annual meeting of the American Society for Radiation Oncology (ASTRO) is designed to disseminate new scientific findings and technical advances to professionals. Best practices of scientific dissemination require that some level of uncertainty (or imprecision) is provided. Methods and Materials: A total of 279 scientific abstracts were selected for oral presentation in a clinical session at the 2013 ASTRO Annual Meeting. A random sample of these abstracts was reviewed to determine whether a 95% confidence interval (95% CI) or analogous measure of precision was provided for time-to-event analyses. Results: A sample of 140 abstracts was reviewed. Of the 65 abstracts with Kaplan-Meier or cumulative incidence analyses, 6 included some measure of precision (6 of 65 = 9%; 95% CI, 2-16). Of the 43 abstracts reporting ratios for time-to-event analyses (eg, hazard ratio, risk ratio), 22 included some measure of precision (22 of 43 = 51%; 95% CI, 36-66). Conclusions: Measures of precision are not provided in a significant percentage of abstracts selected for oral presentation at the Annual Meeting of ASTRO.

  1. Process of Coping with Radiation Therapy.

    ERIC Educational Resources Information Center

    Johnson, Jean E.; And Others

    1989-01-01

    Evaluated ability of self-regulation and emotional-drive theories to explain effects of informational intervention entailing objective descriptions of experience on outcomes of coping with radiation therapy among 84 men with prostate cancer. Consistent with self-regulation theory, similarity between expectations and experience and degree of…

  2. Evolution of the radiation processing industry

    SciTech Connect

    Cleland, Marshall R.

    2013-04-19

    Early investigations of the effects of treating materials with ionizing radiations began in 1894 with the irradiation of gases at atmospheric pressure using cathode rays from a Crookes gas-discharge tube, in 1895 with the discovery of X-rays emitted from a Crookes tube, and in 1896 with the discovery of radioactivity in uranium. In 1897, small electrically charged particles were detected and identified in the gas discharges inside Crookes tubes. These particles were then named electrons. During the next three decades, it was found that these novel forms of energy could produce ions to initiate chemical reactions in some gases and liquids. By 1921, it had also been shown that insects, parasites and bacteria could be killed by treatment with ionizing radiation. In 1925, a high-vacuum tube with a thermionic cathode and a thin metallic anode was developed to produce electron beams in air by using accelerating potentials up to 250 kilovolts. That unique apparatus was the precursor of the many types of electron accelerators that have been developed since then for a variety of industrial applications. In 1929, the vulcanization of natural rubber without using any chemical additives was achieved by irradiation with electrons from a 250 kilovolt accelerator. In 1939, several liquid monomers were polymerized by treatment with gamma rays from radioactive nuclides. These early results were not exploited before the end of World War II because intense sources of ionizing radiation were not available then. Shortly after that war, there was increased interest in developing the peaceful uses of atomic energy, which included the chemical and biological effects of radiation exposures. Many uses that have been developed since then are described briefly in this paper. These industrial applications are now producing billions of US dollars in revenue every year.

  3. Evolution of the radiation processing industry

    NASA Astrophysics Data System (ADS)

    Cleland, Marshall R.

    2013-04-01

    Early investigations of the effects of treating materials with ionizing radiations began in 1894 with the irradiation of gases at atmospheric pressure using cathode rays from a Crookes gas-discharge tube, in 1895 with the discovery of X-rays emitted from a Crookes tube, and in 1896 with the discovery of radioactivity in uranium. In 1897, small electrically charged particles were detected and identified in the gas discharges inside Crookes tubes. These particles were then named electrons. During the next three decades, it was found that these novel forms of energy could produce ions to initiate chemical reactions in some gases and liquids. By 1921, it had also been shown that insects, parasites and bacteria could be killed by treatment with ionizing radiation. In 1925, a high-vacuum tube with a thermionic cathode and a thin metallic anode was developed to produce electron beams in air by using accelerating potentials up to 250 kilovolts. That unique apparatus was the precursor of the many types of electron accelerators that have been developed since then for a variety of industrial applications. In 1929, the vulcanization of natural rubber without using any chemical additives was achieved by irradiation with electrons from a 250 kilovolt accelerator. In 1939, several liquid monomers were polymerized by treatment with gamma rays from radioactive nuclides. These early results were not exploited before the end of World War II because intense sources of ionizing radiation were not available then. Shortly after that war, there was increased interest in developing the peaceful uses of atomic energy, which included the chemical and biological effects of radiation exposures. Many uses that have been developed since then are described briefly in this paper. These industrial applications are now producing billions of US dollars in revenue every year.

  4. Perioperative employee annual evaluations: a 30-second process.

    PubMed

    Olmstead, John; Falcone, Deborah; Lopez, Jacy; Sharpe, Lorraine; Michna, Jody

    2012-12-01

    In response to complaints about the annual evaluation tool used at The Community Hospital in Munster, Indiana, the surgical services management team created a tool to rate the perioperative RNs on skills pertinent to the surgical services department. The hospital-wide evaluation tool uses vague criteria, which are regularly challenged by employees who disagree with their manager's evaluation. The new Surgical Services Employee Evaluation takes a manager approximately 30 seconds to complete and can be added to the generic hospital evaluation form to make the employee evaluation more accurate and meaningful. The tool evaluates three major categories: teamwork, patient care, and job preparation. Use of this additional tool has greatly reduced postevaluation employee complaints, and the tool is now being used in other departments, with slight department-specific variations. Employees now express less frustration with annual evaluations, and managers report a high degree of satisfaction with the tool because it helps them in the difficult task of employee evaluation and counseling. PMID:23178010

  5. Utilization of carbohydrates by radiation processing

    NASA Astrophysics Data System (ADS)

    Kume, T.; Nagasawa, N.; Yoshii, F.

    2002-03-01

    Upgrading and utilization of carbohydrates such as chitosan, sodium alginate, carrageenan, cellulose, pectin have been investigated for recycling these bio-resources and reducing the environmental pollution. These carbohydrates were easily degraded by irradiation and various kinds of biological activities such as anti-microbial activity, promotion of plant growth, suppression of heavy metal stress, phytoalexins induction, etc. were induced. On the other hand, some carbohydrate derivatives, carboxymethylcellulose and carboxymethylstarch, could be crosslinked under certain radiation condition and produce the biodegradable hydrogel for medical and agricultural use.

  6. Committee on Interagency Radiation Research and Policy Coordination second annual report, July 1, 1985--June 30, 1986

    SciTech Connect

    Young, A.L.

    1996-06-30

    This is the second annual report of the Committee on Interagency Radiation Research and Policy Coordination (CIRRPC). CIRRPC was established on April 9, 1984, to replace the Committee on Interagency Radiation Policy and was assigned responsibilities of the former Interagency Radiation Research Committee and former Radiation Policy Council. CIRRPC is chartered under the Federal Coordinating Council for Science, Engineering and Technology (FCCSET) and reports to the Office of Science and Technology Policy (OSTP), Executive Office of the President. Its overall charge is to coordinate radiation matters between agencies, evaluate radiation research, and provide advice on the formulation of radiation policy. During CIRRPC`s second year, the member agencies have called upon this interagency resource to assist in coordinating science and policy issues and to provide a vehicle to accomplish multiagency tasks.

  7. Reaction of runaway electron distributions to radiative processes

    NASA Astrophysics Data System (ADS)

    Stahl, Adam; Embréus, Ola; Hirvijoki, Eero; Pusztai, István; Decker, Joan; Newton, Sarah L.; Fülöp, Tünde

    2015-11-01

    The emission of electromagnetic radiation by a charged particle in accelerated motion is associated with a reduction in its energy, accounted for by the inclusion of a radiation reaction force in the kinetic equation. For runaway electrons in plasmas, the dominant radiative processes are the emission of bremsstrahlung and synchrotron radiation. In this contribution, we investigate the impact of the associated radiation reaction forces on the runaway electron distribution, using both analytical and numerical studies, and discuss the corresponding change to the runaway electron growth rate, which can be substantial. We also report on the formation of non-monotonic features in the runaway electron tail as a consequence of the more complicated momentum-space dynamics in the presence of radiation reaction.

  8. Process and Radiation Induced Defects in Electronic Materials and Devices

    NASA Technical Reports Server (NTRS)

    Washington, Kenneth; Fogarty, T. N.

    1997-01-01

    Process and radiation induced defects are characterized by a variety of electrical techniques, including capacitance-voltage measurements and charge pumping. Separation of defect type into stacking faults, displacement damage, oxide traps, interface states, etc. and their related causes are discussed. The defects are then related to effects on device parameters. Silicon MOS technology is emphasized. Several reviews of radiation effects and silicon processing exist.

  9. Effect of ultraviolet radiation on chlorophyll, carotenoid, protein and proline contents of some annual desert plants.

    PubMed

    Salama, Hediat M H; Al Watban, Ahlam A; Al-Fughom, Anoud T

    2011-01-01

    Investigation was carried out to find whether enhanced ultraviolet radiation influences the Malva parviflora L., Plantago major L., Rumex vesicarius L. and Sismbrium erysimoids Desf. of some annual desert plants. The seeds were grown in plastic pots equally filled with a pre-sieved normal sandy soil for 1 month. The planted pots from each species were randomly divided into equal groups (three groups). Plants of the first group exposed to white-light tubes (400-700 nm) 60 w and UV (365 nm) 8 w tubes. The second group was exposed to white-light tubes (400-700 nm) 60 w and UV (302 nm) 8 w tubes. The third group was exposed to white-light tubes (400-700 nm) 60 w and UV (254 nm) 8 w tubes, respectively, for six days. The results indicated that the chlorophyll contents were affected by enhanced UV radiation. The chlorophyll a, b, and total contents were decreased compared with the control values and reduced with the enhanced UV radiation, but the carotenoid was increased compared with the control and also reduced with the enhanced UV radiation. So, the contents of chlorophylls varied considerably. M. parviflora showed the highest constitutive levels of accumulated chlorophyll a, b, and total chlorophyll (0.463, 0.307 and 0.774 mg g(-1) f w) among the investigated plant species. P. major showed the lowest constitutive levels of the chloroplast pigments, 0.0036, 0.0038 and 0.0075 mg g(-1) f w for chlorophyll a, b, and total chlorophyll at UV-365 nm, respectively. The protein content was decreased significantly in both root and shoot systems compared with the control values but, it was increased with increasing wave lengths of UV-radiation of all tested plants. R. vesicarius showed the highest protein contents among the investigated plants; its content was 3.8 mg g(-1) f w at UV-365 nm in shoot system. On the other hand, decreasing ultraviolet wave length induced a highly significant increase in the level of proline in both root and shoot of all

  10. Annual Conference on Nuclear and Space Radiation Effects, 16th, Santa Cruz, Calif., July 17-20, 1979, Proceedings

    NASA Technical Reports Server (NTRS)

    Bombardt, J.

    1979-01-01

    Papers are presented on the following topics: radiation effects in bipolar microcircuits; basic radiation mechanisms in materials and devices; energy deposition and dosimetry; and system responses from SGEMP, IEMP, and EMP. Also considered are basic processes in SGEMP and IEMP, radiation effects in MOS microcircuits, and space radiation effects and spacecraft charging.

  11. Annual and interannual variations of Earth-emitted radiation based on a 10-year data set

    NASA Technical Reports Server (NTRS)

    Bess, T. Dale; Smith, G. Louis; Charlock, Thomas P.; Rose, Fred G.

    1989-01-01

    The method of empirical orthogonal functions (EOF) was applied to a 10-year data set of outgoing longwave radiation. Spherical harmonic functions are used as a basis set for producing equal area map results. The following findings are noted. The first EOF accounts for 66 percent of the variance. After that, each EOF accounts for only a small variance, forming a slowly converging series. The first two EOF's describe mainly the annual cycle. The third EOF is primarily the semiannual cycle although many other EOF's also contain significant semiannual parts. These results reaffirm those based on a shorter data set. In addition, a much stronger spring/fall mode was found in the central equatorial Pacific Ocean for the second EOF than was found earlier. This difference is attributed to the use of broadband radiometer data which were available for the present study. The earlier study used data from a window channel instrument which is not as sensitive to water vapor variations. The fourth EOF describes much of the 1976 to 1977 and 1982 to 1983 ENSO phenomena. There is typically a gap in the spectrum between a semiannual peak and the annual cycle for all but the first EOF. A semiannual OLR dipole straddles the Asian-Australian monsoon track.

  12. A basic interpretation of the technical language of radiation processing

    NASA Astrophysics Data System (ADS)

    Deeley, Catherine M.

    2004-09-01

    For the food producer contemplating the purchase of radiation processing equipment the task of evaluating the strengths and weaknesses of the available technologies, electron beam (E-beam), X-ray and gamma, to determine the best option for their application, is onerous. Not only is the level of investment daunting but also, to be sure of comparing like with like, the evaluator requires a basic understanding of the science underpinning radiation processing. There have been many papers published that provide technical specialists with a rigorous interpretation of this science (In: Gaughran, E.R.L., Goudie, A.J. (Eds.), Technical Developments and Prospects of Sterilization by Ionizing Radiation, International Conference, Vienna. Multiscience Publications Ltd., pp. 145-172). The objective for this paper is to give non-specialists an introduction to the language of radiation processing and to clarify some of the terminology associated with the use of radioactive sources for this application.

  13. Influence of radiation processing of grapes on wine quality

    NASA Astrophysics Data System (ADS)

    Gupta, Sumit; Padole, Rupali; Variyar, Prasad S.; Sharma, Arun

    2015-06-01

    Grapes (Var. Shiraz and Cabernet) were subjected to radiation processing (up to 2 kGy) and wines were prepared and matured (4 months, 15 °C). The wines were analyzed for chromatic characteristics, total anthocyanin (TA), phenolic (TP) and total antioxidant (TAC) content. Aroma of wines was analyzed by GC/MS and sensory analysis was carried out using descriptive analysis. TA, TP and TAC were 77, 31 and 37 percent higher for irradiated (1500 Gy) Cabernet wines, while irradiated Shiraz wines demonstrated 47, 18 and 19 percent higher TA, TP and TAC, respectively. HPLC-DAD analysis revealed that radiation processing of grapes resulted in increased extraction of phenolic constituents in wine with no qualitative changes. No major radiation induced changes were observed in aroma constituents of wine. Sensory analysis revealed that 1500 Gy irradiated samples had higher fruity and berry notes. Thus, radiation processing of grapes resulted in wines with improved organoleptic and antioxidant properties.

  14. Food processors requirements met by radiation processing

    NASA Astrophysics Data System (ADS)

    Durante, Raymond W.

    2002-03-01

    Processing food using irradiation provides significant advantages to food producers by destroying harmful pathogens and extending shelf life without any detectable physical or chemical changes. It is expected that through increased public education, food irradiation will emerge as a viable commercial industry. Food production in most countries involves state of the art manufacturing, packaging, labeling, and shipping techniques that provides maximum efficiency and profit. In the United States, food sales are extremely competitive and profit margins small. Most food producers have heavily invested in equipment and are hesitant to modify their equipment. Meat and poultry producers in particular utilize sophisticated production machinery that processes enormous volumes of product on a continuous basis. It is incumbent on the food irradiation equipment suppliers to develop equipment that can easily merge with existing processes without requiring major changes to either the final food product or the process utilized to produce that product. Before a food producer can include irradiation as part of their food production process, they must be certain the available equipment meets their needs. This paper will examine several major requirements of food processors that will most likely have to be provided by the supplier of the irradiation equipment.

  15. ANNUAL PROGRESS REPORT. MARKERS OF THE LOW-DOSE RADIATION RESPONSE

    EPA Science Inventory

    One of the major challenges in the field of radiation biology is to correlate the results of biochemical studies with the process of DNA repair as it occurs in the living cell. The overall goal of this project is to develop better methods for visualizing DNA double-strand breaks ...

  16. Accessing Topographic Effects on Solar Radiation Distribution and Ecohydrological Processes

    NASA Astrophysics Data System (ADS)

    Fang, Y.; Niu, G. Y.; Troch, P. A. A.; Paniconi, C.; Durcik, M.; Chorover, J.

    2014-12-01

    Solar radiation is the driving force for terrestrial ecohydrological processes. In mountainous regions, solar radiation reaching the land surface is strongly affected by topographic conditions (e.g., terrain slope and aspect) resulting in unevenly distributed solar radiation. This further affects ecohydrological processes including evapotranspiration, snowmelt, and runoff. However, most distributed hydrological models directly use measured or directly interpolated (e.g. IDW) solar radiation as inputs, not accounting for the topographic effects on solar radiation distribution. In this study, we first implemented a solar radiation spatial interpolation scheme to a fully integrated catchment-scale ecohydrological model by taking into account the topographic effects on direct (shading), diffuse (scattering) and reflected solar radiation. The resulting spatial distribution is more realistic than the direct interpolation. We applied the scheme to Marshall Gulch in Arizona, a mountainous catchment at different spatial resolutions. We will present some modeling results to show the topographic effects on solar radiation distribution, snow mass, vegetation growth, and runoff production, as well as the model sensitivity to modeling resolutions.

  17. ENVIRONMENTAL ASSESSMENT OF COAL CLEANING PROCESSES. SECOND ANNUAL REPORT

    EPA Science Inventory

    The report describes the second year's work for EPA by Battelle's Columbus Laboratories on an environmental assessment of coal cleaning processes. Program activities included systems studies, data acquisition, and general program support. (1) Systems studies have been directed at...

  18. P1 Truss Radiator assembly processing at KSC

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- In the Space Station Processing Facility, workers prepare to attach an overhead crane to the radiator assembly that just arrived. The radiator is part of the payload on mission STS-113, which also includes the first port truss segment, P1 Truss, to be attached to the central truss segment, S0 Truss, on the International Space Station. Once delivered, the will remain stowed until flight 12A.1. STS-113 is scheduled to launch Oct. 6, 2002

  19. P1 Truss Radiator assembly processing at KSC

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- In the Space Station Processing Facility, workers oversee the lowering of the newly arrived radiator assembly onto a workstand. The radiator is part of the payload on mission STS-113, which also includes the first port truss segment, P1 Truss, to be attached to the central truss segment, S0 Truss, on the International Space Station. Once delivered, the will remain stowed until flight 12A.1. STS-113 is scheduled to launch Oct. 6, 2002

  20. P1 Truss Radiator assembly processing at KSC

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- In the Space Station Processing Facility, an overhead crane moves the newly arrived radiator assembly toward a workstand. The radiator is part of the payload on mission STS-113, which also includes the first port truss segment, P1 Truss, to be attached to the central truss segment, S0 Truss, on the International Space Station. Once delivered, the will remain stowed until flight 12A.1. STS-113 is scheduled to launch Oct. 6, 2002

  1. P1 Truss Radiator assembly processing at KSC

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- In the Space Station Processing Facility, workers help guide the newly arrived radiator assembly onto a workstand. The radiator is part of the payload on mission STS-113, which also includes the first port truss segment, P1 Truss, to be attached to the central truss segment, S0 Truss, on the International Space Station. Once delivered, the will remain stowed until flight 12A.1. STS-113 is scheduled to launch Oct. 6, 2002

  2. On possibility of diamond formations in radiation process

    NASA Technical Reports Server (NTRS)

    Fisenko, A. V.; Semjonova, L. F.; Bolsheva, L. N.; Grachjova, T. V.; Verchovsky, A. B.; Shukolyukov, Yu. A.

    1993-01-01

    The possibility of diamond formation in radiation processes was checked by studying diamond contents in carburanium sample. The diamonds were not found and this result is discussed. At present one possible process of formation of nanometer-size diamond crystals in some meteorites and Earth's diamonds (carbonado), the radiation mechanism, is suggested: the formation of diamonds from carbonaceous matter in tracks of U fragment fissions and heavy fragmentation due to the action of energetic particles of cosmic rays. Bjakov et. al. have carried out the calculations and shown that the volume of formed diamonds in carbonaceous chondrites by radiation processes corresponds to discovery of diamond volume in chondrites. The discovery by Ozima et. al. of the unsupported fission of Xe and Kr in carbonado supports the supposition that carbonado could be formed by radiation processes. The possibility of diamond formation in radiation processes leads to the study of diamond contents in Earth's samples enriched by uranium and carbon. The attempt to release the diamonds from carburanium was undertaken.

  3. Food Processing and Agriculture. Wisconsin Annual Farm Labor Report, 1968.

    ERIC Educational Resources Information Center

    Wisconsin State Employment Service, Madison.

    A yearly report on the migrant farm worker situation in Wisconsin evaluates the year 1968 in relation to past years and makes projections for the future. Comparisons are made of trends in year-round employment practices, seasonal food processing, the cherry industry, and the cucumber industry. The report includes a discussion on the social aspects…

  4. Radiation processing of natural polymers: The IAEA contribution

    NASA Astrophysics Data System (ADS)

    Haji-Saeid, Mohammad; Safrany, Agnes; Sampa, Maria Helena de O.; Ramamoorthy, Natesan

    2010-03-01

    Radiation processing offers a clean and additive-free method for preparation of value-added novel materials based on renewable, non-toxic, and biodegradable natural polymers. Crosslinked natural polymers can be used as hydrogel wound dressings, face cleaning cosmetic masks, adsorbents of toxins, and non-bedsore mats; while low molecular weight products show antibiotic, antioxidant, and plant-growth promoting properties. Recognizing the potential benefits that radiation technology can offer for processing of natural polymers into useful products, the IAEA implemented a coordinated research project (CRP) on "Development of Radiation-processed products of Natural Polymers for application in Agriculture, Healthcare, Industry and Environment". This CRP was launched at the end of 2007 with participation of 16 MS to help connecting radiation technology and end-users to derive enhanced benefits from these new value-added products of radiation-processed natural materials. In this paper the results of activities in participating MS related to this work will be presented.

  5. The application of a linear electron accelerator in radiation processing

    NASA Astrophysics Data System (ADS)

    Ruiying, Zhou; Binglin, Wang; Wenxiu, Chen; Yongbao, Gu; Yinfen, Zhang; Simin, Qian; Andong, Liu; Peide, Wang

    A 3-5 MeV electron beam generated by a BF-5 type linear electron accelerator has been used in some radiation processing works, such as, (1) The cross-linking technology by radiation for the polyethylene foaming processing --- the correlation between the cross-linkage and the absorbed dose, the relation between the elongation of foaming polyethylene and the dose, the relation between the size of the cavities and the gelatin rate and the optimum range of dosage for foaming have been found. (2) The research work on the fast switch thyristor irradiated by electron beam --- The relation between the absorbed dose and the life-time of minority carriers has been studied and the optimum condition for radiation processing was determined. This process is much better than the conventional gold diffusion in raising the quality and end-product rate of these devices. Besides, we have made some testing works on the hereditary mutation of plant seeds and microorganism mutation induced by electron radiation and radiation sterilization for some medical instruments and foods.

  6. International cooperative effort to establish dosimetry standardization for radiation processing

    SciTech Connect

    Farrar, H. IV

    1989-01-01

    Radiation processing is a rapidly developing technology with numerous applications in food treatment, sterilization, and polymer modification. The effectiveness of the process depends, however, on the proper application of dose and its measurement. These aspects are being considered by a wide group of experts from around the world who have joined together to write a comprehensive set of standards for dosimetry for radiation processing. Originally formed in 1984 to develop standards for food processing dosimetry, the group has now expanded into a full subcommittee of the American Society for Testing and Materials (ASTM), with 97 members from 19 countries. The scope of the standards now includes dosimetry for all forms of radiation processing. The group has now completed and published four standards, and is working on an additional seven. Three are specifically for food applications and the others are for all radiation applications, including food processing. Together, this set of standards will specify acceptable guidelines and methods for accomplishing the required irradiation treatment, and will be available for adoption by national regulatory agencies in their procedures and protocols. 1 tab.

  7. Radiation processing in india-current R & D activities

    NASA Astrophysics Data System (ADS)

    Majali, A. B.; Sabharwal, S.

    1995-09-01

    Radiation processing is an area of vigorous activity in today's India. With the indigenous expertise in Co source and irradiator technology, potentially promising applications such as sustained drug delivery systems, vulcanization of natural rubber latex (RVNRL), and degradation of polytetrafluoroethylene (PTFE) are presently investigated. Over the last four years, technologies for RVNRL and PTFE degradation have been scaled upto pilot scale operations, while radiation polymerized polymer systems have been developed for controlled release of certain drugs. With the commissioning of the 2 MeV EB machine in late 1988, a few EB based processes have also been commercially exploited. The paper briefly reviews these and presents the significant results obtained.

  8. Development of a radiation-hard CMOS process

    NASA Technical Reports Server (NTRS)

    Power, W. L.

    1983-01-01

    It is recommended that various techniques be investigated which appear to have the potential for improving the radiation hardness of CMOS devices for prolonged space flight mission. The three key recommended processing techniques are: (1) making the gate oxide thin. It has been shown that radiation degradation is proportional to the cube of oxide thickness so that a relatively small reduction in thickness can greatly improve radiation resistance; (2) cleanliness and contamination control; and (3) to investigate different oxide growth (low temperature dry, TCE and HCL). All three produce high quality clean oxides, which are more radiation tolerant. Technique 2 addresses the reduction of metallic contamination. Technique 3 will produce a higher quality oxide by using slow growth rate conditions, and will minimize the effects of any residual sodium contamination through the introduction of hydrogen and chlorine into the oxide during growth.

  9. Radiation processing of dry food ingredients - a review

    NASA Astrophysics Data System (ADS)

    Farkas, J.

    Radiation decontamination of dry ingredients, herbs and enzyme preparations is a technically feasible, economically viable and safe physical process. The procedure is direct, simple, requires no additives, does not leave residues and is highly efficient. Its dose requirement is moderate. Radiation doses of 3 to 10 kGy proved to be sufficient to reduce the viable cell counts to a satisfactory level. Ionizing radiations do not cause any significant rise in temperature and the flavour, texture or other important technological or sensory properties of most ingredients are not influenced at radiation doses necessary for a satisfactory decontamination. The microflora surviving the cell-count reduction by irradiation is more sensitive to subsequent food processing treatments than the microflora of untreated ingredients. Recontamination can be prevented since the product can be irradiated in its final packaging. Irradiation can be carried out in commercial containers and it results in considerable savings of energy and labour as compared to alternative decontamination techniques. Radiation processing of dry ingredients is an emerging technology in several countries and more-and-more clearances on irradiated foods are issued or expected to be granted in the near future.

  10. Modeling of clouds and radiation for developing parameterizations for general circulation models. Annual report, 1995

    SciTech Connect

    Toon, O.B.; Westphal, D.L.

    1996-07-01

    We have used a hierarchy of numerical models for cirrus and stratus clouds and for radiative transfer to improve the reliability of general circulation models. Our detailed cloud microphysical model includes all of the physical processes believed to control the lifecycles of liquid and ice clouds in the troposphere. We have worked on specific GCM parameterizations for the radiative properties of cirrus clouds, making use of a mesocale model as the test-bed for the parameterizations. We have also modeled cirrus cloud properties with a detailed cloud physics model to better understand how the radiatively important properties of cirrus are controlled by their environment. We have used another cloud microphysics model to investigate of the interactions between aerosols and clouds. This work is some of the first to follow the details of interactions between aerosols and cloud droplets and has shown some unexpected relations between clouds and aerosols. We have also used line-by- line radiative transfer results verified with ARM data, to derive a GCMS.

  11. Effectiveness of radiation processing for elimination of Salmonella Typhimurium from minimally processed pineapple (Ananas comosus Merr.).

    PubMed

    Shashidhar, Ravindranath; Dhokane, Varsha S; Hajare, Sachin N; Sharma, Arun; Bandekar, Jayant R

    2007-04-01

    The microbiological quality of market samples of minimally processed (MP) pineapple was examined. The effectiveness of radiation treatment in eliminating Salmonella Typhimurium from laboratory inoculated ready-to-eat pineapple slices was also studied. Microbiological quality of minimally processed pineapple samples from Mumbai market was poor; 8.8% of the samples were positive for Salmonella. D(10) (the radiation dose required to reduce bacterial population by 90%) value for S. Typhimurium inoculated in pineapple was 0.242 kGy. Inoculated pack studies in minimally processed pineapple showed that the treatment with a 2-kGy dose of gamma radiation could eliminate 5 log CFU/g of S. Typhimurium. The pathogen was not detected from radiation-processed samples up to 12 d during storage at 4 and 10 degrees C. The processing of market samples with 1 and 2 kGy was effective in improving the microbiological quality of these products. PMID:17995808

  12. NATO/CCMS PILOT STUDY CLEAN PRODUCTS AND PROCESSES (PHASE II) 2003 ANNUAL REPORT

    EPA Science Inventory

    The 6th annual meeting of the NATO CCMS Pilot Study, Clean Products and Processes, was held in Cetraro, Italy, from May 11 to 15, 2003. This was also the first meeting of its Phase II study. 24 country representatives attended this meeting. This meeting was very ably run by th...

  13. 45 CFR 270.10 - How will we annually review the award process?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 2 2014-10-01 2012-10-01 true How will we annually review the award process? 270.10 Section 270.10 Public Welfare Regulations Relating to Public Welfare OFFICE OF FAMILY ASSISTANCE (ASSISTANCE PROGRAMS), ADMINISTRATION FOR CHILDREN AND FAMILIES, DEPARTMENT OF HEALTH AND HUMAN SERVICES HIGH PERFORMANCE BONUS AWARDS § 270.10...

  14. 45 CFR 270.10 - How will we annually review the award process?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false How will we annually review the award process? 270.10 Section 270.10 Public Welfare Regulations Relating to Public Welfare OFFICE OF FAMILY ASSISTANCE (ASSISTANCE PROGRAMS), ADMINISTRATION FOR CHILDREN AND FAMILIES, DEPARTMENT OF HEALTH AND HUMAN SERVICES HIGH PERFORMANCE BONUS AWARDS § 270.10...

  15. 40 CFR 63.1431 - Process vent annual epoxides emission factor plan requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... factor plan requirements. 63.1431 Section 63.1431 Protection of Environment ENVIRONMENTAL PROTECTION... group determination procedures in the NESHAP for Group I Polymers and Resins (40 CFR part 63, subpart U... Production § 63.1431 Process vent annual epoxides emission factor plan requirements. (a) Applicability...

  16. 45 CFR 270.10 - How will we annually review the award process?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 2 2013-10-01 2012-10-01 true How will we annually review the award process? 270.10 Section 270.10 Public Welfare Regulations Relating to Public Welfare OFFICE OF FAMILY ASSISTANCE (ASSISTANCE PROGRAMS), ADMINISTRATION FOR CHILDREN AND FAMILIES, DEPARTMENT OF HEALTH AND HUMAN SERVICES HIGH PERFORMANCE BONUS AWARDS § 270.10...

  17. One Hair Postulate for Hawking Radiation as Tunneling Process

    NASA Astrophysics Data System (ADS)

    Dong, Hui; Cai, Qing-Yu; Liu, Xu-Feng; Sun, Chang-Pu

    2014-03-01

    For Hawking radiation, treated as a tunneling process, the no-hair theorem of black hole together with the law of energy conservation is utilized to postulate that the tunneling rate only depends on the external qualities (e.g., the mass for the Schwarzschild black hole) and the energy of the radiated particle. This postulate is justified by the WKB approximation for calculating the tunneling probability. Based on this postulate, a general formula for the tunneling probability is derived without referring to the concrete form of black hole metric. This formula implies an intrinsic correlation between the successive processes of the black hole radiation of two or more particles. It also suggests a kind of entropy conservation and thus resolves the puzzle of black hole information loss in some sense.

  18. Annual and semi-annual variability in the lower and upper atmosphere-ionosphere coupling processes by observations from Abastumani (41.75 N, 42.82 E)

    NASA Astrophysics Data System (ADS)

    Didebulidze, G. G.; Todua, M.; Javakhishvili, G.

    2015-12-01

    The importance of annual and semi-annual variability in the long-term variations of the ionosphere F2 layer parameters (NmF2, hmF2), the hydroxyl OH bands, the oxygen green 557.7 nm and red 630.0 line intensities observed from Abastumani is noted. The amplitudes of the semi-annual variations of these upper atmosphere-ionosphere parameters with maxima at equinoctial months depend on the value of the planetary geomagnetic Ap index, also observed in the inter-annual distribution of the total ozone content (TOC) and cloud covering over this region of South Caucasus. The observed dependence of semi-annual variations of these parameters on Ap index indicated possible influence of cosmic factors on the lower and upper atmosphere-ionosphere coupling processes.

  19. Processing and circuit design enhance a data converter's radiation tolerance

    SciTech Connect

    Heuner, R.; Zazzu, V.; Pennisi, L.

    1988-12-01

    Rad-hard CMOS/SOS processing has been applied to a novel comparator-inverter circuit design to develop 6 and 8-bit parallel (flash) ADC (analog-to-digital converter) circuits featuring high-speed operation, low power consumption, and total-dose radiation tolerances up to 1 Mrad(Si).

  20. HBCU (Historically Black Colleges and Universities) solar radiation network annual report: FY 1986

    SciTech Connect

    Stoffel, T.L.

    1987-07-01

    This report summarizes the development of the Historically Black Colleges and Universities (HBCU) Solar Radiation Network through fiscal year 1986. In operation since November 1985, the six-station network provides 5-minute averaged measurements of global ad diffuse horizontal solar irradiance that are processed at the Solar Energy Research Institute (SERI) to improve the assessment of the solar radiation resource in the southeastern United States. One of the stations also measures the direct-normal solar irradiance with a pyrheliometer mounted in an automatic sun tracker. The report also describes the HBCU project's technology transfer goals, which involve the dissemination of solar resource information, the establishment of academic research programs in solar energy, and the summer student and visiting faculty programs at SERI.

  1. The Iron Project:. Radiative Atomic Processes in Astrophysics

    NASA Astrophysics Data System (ADS)

    Nahar, Sultana N.

    2011-06-01

    Astronomical objects, such as, stars, galaxies, blackhole environments, etc are studied through their spectra produced by various atomic processes in their plasmas. The positions, shifts, and strengths of the spectral lines provide information on physical processes with elements in all ionization states, and various diagnostics for temperature, density, distance, etc of these objects. With presence of a radiative source, such as a star, the astrophysical plasma is dominated by radiative atomic processes such as photoionization, electron-ion recombination, bound-bound transitions or photo-excitations and de-excitations. The relevant atomic parameters, such as photoionization cross sections, electron-ion recombination rate coefficients, oscillator strengths, radiative transition rates, rates for dielectronic satellite lines etc are needed to be highly accurate for precise diagnostics of physical conditions as well as accurate modeling, such as, for opacities of astrophysical plasmas. for opacities of astrophysical plasmas. This report illustrates detailed features of radiative atomic processes obtained from accurate ab initio methods of the latest developments in theoretical quantum mechanical calculations, especially under the international collaborations known as the Iron Project (IP) and the Opacity Project (OP). These projects aim in accurate study of radiative and collsional atomic processes of all astrophysically abundant atoms and ions, from hydrogen to nickel, and calculate stellar opacities and have resulted in a large number of atomic parameters for photoionization and radiative transition probabilities. The unified method, which is an extension of the OP and the IP, is a self-consistent treatment for the total electron-ion recombination and photoionization. It incorporates both the radiative and the dielectronic recombination processes and provides total recombination rates and level-specific recombination rates for hundreds of levels for a wide range of

  2. Process for radiation grafting hydrogels onto organic polymeric substrates

    DOEpatents

    Ratner, Buddy D.; Hoffman, Allan S.

    1976-01-01

    An improved process for radiation grafting of hydrogels onto organic polymeric substrates is provided comprising the steps of incorporating an effective amount of cupric or ferric ions in an aqueous graft solution consisting of N-vinyl-2 - pyrrolidone or mixture of N-vinyl-2 - pyrrolidone and other monomers, e.g., 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, propylene glycol acrylate, acrylamide, methacrylic acid and methacrylamide, immersing an organic polymeric substrate in the aqueous graft solution and thereafter subjecting the contacted substrate with ionizing radiation.

  3. 50 CFR Table 17 to Part 679 - Process Codes for Use With State of Alaska Commercial Operator's Annual Report (COAR)

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Commercial Operator's Annual Report (COAR) 17 Table 17 to Part 679 Wildlife and Fisheries FISHERY...) FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 679, Table 17 Table 17 to Part 679—Process Codes for Use With State of Alaska Commercial Operator's Annual Report (COAR) Codes Process Codes...

  4. Twenty new ISO standards on dosimetry for radiation processing

    NASA Astrophysics Data System (ADS)

    Farrar, H., IV

    2000-03-01

    Twenty standards on essentially all aspects of dosimetry for radiation processing were published as new ISO standards in December 1998. The standards are based on 20 standard practices and guides developed over the past 14 years by Subcommittee E10.01 of the American Society for Testing and Materials (ASTM). The transformation to ISO standards using the 'fast track' process under ISO Technical Committee 85 (ISO/TC85) commenced in 1995 and resulted in some overlap of technical information between three of the new standards and the existing ISO Standard 11137 Sterilization of health care products — Requirements for validation and routine control — Radiation sterilization. Although the technical information in these four standards was consistent, compromise wording in the scopes of the three new ISO standards to establish precedence for use were adopted. Two of the new ISO standards are specifically for food irradiation applications, but the majority apply to all forms of gamma, X-ray, and electron beam radiation processing, including dosimetry for sterilization of health care products and the radiation processing of fruit, vegetables, meats, spices, processed foods, plastics, inks, medical wastes, and paper. Most of the standards provide exact procedures for using individual dosimetry systems or for characterizing various types of irradiation facilities, but one covers the selection and calibration of dosimetry systems, and another covers the treatment of uncertainties using the new ISO Type A and Type B evaluations. Unfortunately, nine of the 20 standards just adopted by the ISO are not the most recent versions of these standards and are therefore already out of date. To help solve this problem, efforts are being made to develop procedures to coordinate the ASTM and ISO development and revision processes for these and future ASTM-originating dosimetry standards. In the meantime, an additional four dosimetry standards have recently been published by the ASTM but

  5. Radiation processing applications in the Czechoslovak water treatment technologies

    NASA Astrophysics Data System (ADS)

    Vacek, K.; Pastuszek, F.; Sedláček, M.

    The regeneration of biologically clogged water wells by radiation proved to be a successful and economically beneficial process among other promising applications of ionizing radiation in the water supply technology. The application conditions and experience are mentioned. The potential pathogenic Mycobacteria occuring in the warm washing and bathing water are resistant against usual chlorine and ozone concentrations. The radiation sensitivity of Mycobacteria allowed to suggest a device for their destroying by radiation. Some toxic substances in the underground water can be efficiently degraded by gamma radiation directly in the wells drilled as a hydraulic barrier surrounding the contaminated land area. Substantial decrease of CN - concentration and C.O.D. value was observed in water pumped from such well equipped with cobalt sources and charcoal. The removing of pathogenic contamination remains to be the main goal of radiation processing in the water purification technologies. The decrease of liquid sludge specific filter resistance and sedimentation acceleration by irradiation have a minor technological importance. The hygienization of sludge cake from the mechanical belt filter press by electron beam appears to be the optimum application in the Czechoslovak conditions. The potatoes and barley crop yields from experimental plots treated with sludge were higher in comparison with using the manure. Biological sludge from the municipal and food industry water purification plants contains nutritive components. The proper hygienization is a necessary condition for using them as a livestock feed supplement. Feeding experiments with broilers and pigs confirmed the possibility of partial (e.g. 50%) replacement of soya-, bone- or fish flour in feed mixtures by dried sludge hygienized either by heat or by the irradiation.

  6. Non linear processes modulated by low doses of radiation exposure

    NASA Astrophysics Data System (ADS)

    Mariotti, Luca; Ottolenghi, Andrea; Alloni, Daniele; Babini, Gabriele; Morini, Jacopo; Baiocco, Giorgio

    The perturbation induced by radiation impinging on biological targets can stimulate the activation of several different pathways, spanning from the DNA damage processing to intra/extra -cellular signalling. In the mechanistic investigation of radiobiological damage this complex “system” response (e.g. omics, signalling networks, micro-environmental modifications, etc.) has to be taken into account, shifting from a focus on the DNA molecule solely to a systemic/collective view. An additional complication comes from the finding that the individual response of each of the involved processes is often not linear as a function of the dose. In this context, a systems biology approach to investigate the effects of low dose irradiations on intra/extra-cellular signalling will be presented, where low doses of radiation act as a mild perturbation of a robustly interconnected network. Results obtained through a multi-level investigation of both DNA damage repair processes (e.g. gamma-H2AX response) and of the activation kinetics for intra/extra cellular signalling pathways (e.g. NFkB activation) show that the overall cell response is dominated by non-linear processes - such as negative feedbacks - leading to possible non equilibrium steady states and to a poor signal-to-noise ratio. Together with experimental data of radiation perturbed pathways, different modelling approaches will be also discussed.

  7. Evolutionary patterns and processes in the radiation of phyllostomid bats

    PubMed Central

    2011-01-01

    Background The phyllostomid bats present the most extensive ecological and phenotypic radiation known among mammal families. This group is an important model system for studies of cranial ecomorphology and functional optimisation because of the constraints imposed by the requirements of flight. A number of studies supporting phyllostomid adaptation have focused on qualitative descriptions or correlating functional variables and diet, but explicit tests of possible evolutionary mechanisms and scenarios for phenotypic diversification have not been performed. We used a combination of morphometric and comparative methods to test hypotheses regarding the evolutionary processes behind the diversification of phenotype (mandible shape and size) and diet during the phyllostomid radiation. Results The different phyllostomid lineages radiate in mandible shape space, with each feeding specialisation evolving towards different axes. Size and shape evolve quite independently, as the main directions of shape variation are associated with mandible elongation (nectarivores) or the relative size of tooth rows and mandibular processes (sanguivores and frugivores), which are not associated with size changes in the mandible. The early period of phyllostomid diversification is marked by a burst of shape, size, and diet disparity (before 20 Mya), larger than expected by neutral evolution models, settling later to a period of relative phenotypic and ecological stasis. The best fitting evolutionary model for both mandible shape and size divergence was an Ornstein-Uhlenbeck process with five adaptive peaks (insectivory, carnivory, sanguivory, nectarivory and frugivory). Conclusions The radiation of phyllostomid bats presented adaptive and non-adaptive components nested together through the time frame of the family's evolution. The first 10 My of the radiation were marked by strong phenotypic and ecological divergence among ancestors of modern lineages, whereas the remaining 20 My were

  8. Radiation processing with high-energy X-rays

    NASA Astrophysics Data System (ADS)

    Cleland, Marshall R.; Stichelbaut, Frédéric

    2013-03-01

    The radiation processing of materials and commercial products with high-energy X-rays, which are also identified by the German term bremsstrahlung, can produce beneficial changes that are similar to those obtained by irradiation with nuclear gamma rays emitted by cobalt-60 sources. Both X-rays and gamma rays are electromagnetic radiations with short wavelengths and high photon energies that can stimulate chemical reactions by creating ions and free radicals in irradiated materials. Nevertheless, there are some physical differences in these energy sources that can influence the choice for practical applications. The English translation of bremsstrahlung is braking radiatiorn or deceleration radiation. It is produced when energetic electrons are deflected by the strong electric field near an atomic nucleus. The efficiency for producing this kind of electromagnetic energy increases with the kinetic energy of the electrons and the atomic number of the target material. The energy spectrum of the emitted X-ray photons is very broad and extends up to the maximum energy of the incident electrons. In contrast, a cobalt-60 nucleus emits two gamma rays simultaneously, which have well-defined energies. Another significant difference is the angular distribution of the radiation. Nuclear gamma rays are emitted in all directions, but high-energy bremsstrahlung photons are concentrated in the direction of the incident electrons when they strike the target material. This property enables an X-ray processing facility to be more compact than a gamma-ray processing facility with similar throughput capacity, and it increases the penetration and the efficiency for absorbing the emitted X-ray energy in the irradiated material. Recent increases in the electron energy and the electron beam power from modern industrial accelerators have increased the throughput rates in X-ray processing facilities, so that this irradiation method is now economically competitive with large cobalt-60

  9. Occupational radiation exposure at commercial nuclear power reactors and other facilities 1992; Twenty-fifth annual report, Volume 14

    SciTech Connect

    Raddatz, C.T.; Hagemeyer, D.

    1993-12-01

    This report summarizes the occupational radiation exposure information that has been reported to the NRC`s Radiation Exposure Information Reporting System (REIRS) by nuclear power facilities and certain other categories of NRC licensees during the years 1969 through 1992. The bulk of the data presented in the report was obtained from annual radiation exposure reports submitted in accordance with the requirements of 10CFR20.407 and the technical specifications of nuclear power plants. Data on workers terminating their employment at certain NRC licensed facilities were obtained from reports submitted pursuant to 10CFR20.408. The 1992 annual reports submitted by about 364 licensees indicated that approximately 204,365 individuals were monitored, 183,927 of whom were monitored by nuclear power facilities. They incurred an average individual dose of 0.16 rem (cSv) and an average measurable dose of about 0.30 (cSv). Termination radiation exposure reports were analyzed to reveal that about 74,566 individuals completed their employment with one or more of the 364 covered licensees during 1992. Some 71,846 of these individuals terminated from power reactor facilities, and about 9,724 of them were considered to be transient workers who received an average dose of 0.50 rem (cSv).

  10. Radiation Chemistry of Acetohydroxamic Acid in the UREX Process

    SciTech Connect

    Karraker, D.G.

    2002-07-31

    The UREX process is being developed to process irradiated power reactor elements by dissolution in nitric acid and solvent extraction by a variation of the PUREX process.1 Rather than recovering both U and Pu, as in Purex, only U will be recovered by solvent extraction, hence the name ''UREX.'' A complexing agent, acetohydroxamic acid (AHA), will be added to the scrub stream to prevent the extraction of Pu(IV) and Np(VI). AHA (CH3C=ONHOH) is decomposed to gaseous products in waste evaporation, so no solid waste is generated by its addition. AHA is hydrolyzed in acid solution to acetic acid and hydroxylamine at a rate dependent on the acid concentration.2-4 The fuel to be processed is ca 40 years cooled, 30,000-50,000 MWD/MT material; although only a few fission products remain, the Pu isotopes and 241Am generate a radiation field estimated to be 2.6E+02R during processing. (see Appendix for calculation.) This study was conducted to determine the effect of this level of radiation on the stability of AHA during processing.

  11. Ionizing radiation induced catalysis on metal oxide particles. 1998 annual progress report

    SciTech Connect

    Fryberger, T.; Chambers, S.A.; Daschbach, J.L.; Henderson, M.A.; Peden, C.H.F.; Su, Y.; Wang, Y.

    1998-06-01

    'High-level radioactive waste storage tanks within DOE sites contain significant amounts of organic components (solid and liquid phases) in the form of solvents, extractants, complexing agents, process chemicals, cleaning agents and a variety of miscellaneous compounds. These organics pose several safety and pretreatment concerns, particularly for the Hanford tank waste. Remediation technologies are needed that significantly reduce the amounts of problem organics without resulting in toxic or flammable gas emissions, and without requiring thermal treatments. These restrictions pose serious technological barriers for current organic destruction methods which utilize oxidation achieved by thermal or chemical activation. This project focuses on using ionizing radiation (a,b,g) to catalytically destroy organics over oxide materials through reduction/oxidation (redox) chemistry resulting from electron-hole (e{sup -}/h{sup +}) pair generation. Conceptually this process is an extension of visible and near-UV photocatalytic processes known to occur at the interfaces of narrow bandgap semiconductors in both solution and gas phases. In these processes, an electron is excited across the energy gap between the filled and empty states in the semiconductor. The excited electron does reductive chemistry and the hole (where the electron was excited from) does oxidative chemistry. The energy separation between the hole and the excited electron reflects the redox capability of the e{sup -}/h{sup +} pair, and is dictated by the energy of the absorbed photon and the bandgap of the material. The use of ionizing radiation overcomes optical transparency limitations associated with visible and near-UV illumination (g-rays penetrate much farther into a solution than UV/Vis light), and permits the use of wider bandgap materials (such as ZrO{sub 2}) which possess potentially greater redox capabilities than those with narrow bandgap materials. Experiments have been aimed at understanding the

  12. The Impact of Gamma Radiation on Sediment Microbial Processes

    PubMed Central

    Brown, Ashley R.; Boothman, Christopher; Pimblott, Simon M.

    2015-01-01

    Microbial communities have the potential to control the biogeochemical fate of some radionuclides in contaminated land scenarios or in the vicinity of a geological repository for radioactive waste. However, there have been few studies of ionizing radiation effects on microbial communities in sediment systems. Here, acetate and lactate amended sediment microcosms irradiated with gamma radiation at 0.5 or 30 Gy h−1 for 8 weeks all displayed NO3− and Fe(III) reduction, although the rate of Fe(III) reduction was decreased in 30-Gy h−1 treatments. These systems were dominated by fermentation processes. Pyrosequencing indicated that the 30-Gy h−1 treatment resulted in a community dominated by two Clostridial species. In systems containing no added electron donor, irradiation at either dose rate did not restrict NO3−, Fe(III), or SO42− reduction. Rather, Fe(III) reduction was stimulated in the 0.5-Gy h−1-treated systems. In irradiated systems, there was a relative increase in the proportion of bacteria capable of Fe(III) reduction, with Geothrix fermentans and Geobacter sp. identified in the 0.5-Gy h−1 and 30-Gy h−1 treatments, respectively. These results indicate that biogeochemical processes will likely not be restricted by dose rates in such environments, and electron accepting processes may even be stimulated by radiation. PMID:25841009

  13. The impact of gamma radiation on sediment microbial processes.

    PubMed

    Brown, Ashley R; Boothman, Christopher; Pimblott, Simon M; Lloyd, Jonathan R

    2015-06-15

    Microbial communities have the potential to control the biogeochemical fate of some radionuclides in contaminated land scenarios or in the vicinity of a geological repository for radioactive waste. However, there have been few studies of ionizing radiation effects on microbial communities in sediment systems. Here, acetate and lactate amended sediment microcosms irradiated with gamma radiation at 0.5 or 30 Gy h(-1) for 8 weeks all displayed NO3 (-) and Fe(III) reduction, although the rate of Fe(III) reduction was decreased in 30-Gy h(-1) treatments. These systems were dominated by fermentation processes. Pyrosequencing indicated that the 30-Gy h(-1) treatment resulted in a community dominated by two Clostridial species. In systems containing no added electron donor, irradiation at either dose rate did not restrict NO3 (-), Fe(III), or SO4 (2-) reduction. Rather, Fe(III) reduction was stimulated in the 0.5-Gy h(-1)-treated systems. In irradiated systems, there was a relative increase in the proportion of bacteria capable of Fe(III) reduction, with Geothrix fermentans and Geobacter sp. identified in the 0.5-Gy h(-1) and 30-Gy h(-1) treatments, respectively. These results indicate that biogeochemical processes will likely not be restricted by dose rates in such environments, and electron accepting processes may even be stimulated by radiation. PMID:25841009

  14. Annual Report 2006 for Hydrodynamics and Radiation Hydrodynamics with Astrophysical Applications

    SciTech Connect

    R. Paul Drake

    2007-04-05

    We report the ongoing work of our group in hydrodynamics and radiation hydrodynamics with astrophysical applications. During the period of the existing grant, we have carried out two types of experiments at the Omega laser. One set of experiments has studied radiatively collapsing shocks, obtaining data using a backlit pinhole with a 100 ps backlighter and beginning to develop the ability to look into the shock tube with optical or x-ray diagnostics. Other experiments have studied the deeply nonlinear development of the Rayleigh-Taylor (RT) instability from complex initial conditions, using dual-axis radiographic data with backlit pinholes and ungated detectors to complete the data set for a Ph.D. student. We lead a team that is developing a proposal for experiments at the National Ignition Facility and are involved in experiments at NIKE and LIL. All these experiments have applications to astrophysics, discussed in the corresponding papers. We assemble the targets for the experiments at Michigan, where we also prepare many of the simple components. We also have several projects underway in our laboratory involving our x-ray source. The above activities, in addition to a variety of data analysis and design projects, provide good experience for graduate and undergraduates students. In the process of doing this research we have built a research group that uses such work to train junior scientists.

  15. Operation of an industrial radiation processing facility in Mexico

    NASA Astrophysics Data System (ADS)

    Torres C., Gilberto

    A 10 years old JS-6500 industrial Cobalt 60 irradiator was installed in 1980 at the ININ Nuclear Center in Mexico with 960 kGy. The facility was commissioning in August with some minor changes with respect to the original AECL design, in order to give services to different industries and also to do research in several fields. During that year promotional activities were done to increase interest from industry in the use of radiation processing. In 1981, an interruption due to pool's leakage and its reparation, put the facility out of operation. During the next three years the demand increases but never reach more than 50% if the capacity. In that time, the potential users did not show confidence in the process, even knowing that health authorities approved with no restrictions radiation sterilization. Actually, there are 34 different companies irradiating 48 different products. Even those within the same grouping, require different minimum and maximum radiation doses, so the facility has been operated combining products and valumes. The experiences are presented in this paper. Also, maintenance of the irradiator is discussed and some modifications to the original programme have been done due to the necessity to use local spare parts instead of imported ones.

  16. Evolution Characteristics of Electromagnetic Power Radiated in Lightning Discharge Processes.

    PubMed

    Zhao, Jin-cui; Yuan, Ping; Cen, Jian-yong; Li, Ya-jun; Wang, Jie

    2015-06-01

    Combining the spectra of could-to-ground lightning discharge processes obtained by a slit-less spectrograph with synchronous electric field information, the temperature, the conductivity, the current peak, electromagnetic power peak and the luminance of the discharge channel are calculated. The values are in a normal range reported by references. The correlation among cut-off time before a subsequent return stroke, the luminance and electromagnetic power peak of the channel is discussed. The change trends of the conductivity, the current peak and electromagnetic power peak are also investigated. The results show when cut-off time is long, neutralized charges will grow, the current will rise and electromagnetic power radiated from the channel will increase. When the conductivity and the peak of the electric field change increase simultaneously, the current in the channel will rise and electromagnetic power radiated from the channel will be greater. This work will provide some references for calculating optical and electromagnetic energy radiated by lightning discharge processes. PMID:26601350

  17. NATO/CCMS PILOT STUDY CLEAN PRODUCTS AND PROCESSES (PHASE 1) 1998 ANNUAL REPORT (EPA/600/R-98/065)

    EPA Science Inventory

    This annual report presents the proceedings of the first annual NATO/CCMS pilot study meeting in Cincinnati in March 1998. Guest speakers focused on efforts in the research arena of clean products, clean processes, life cycle analysis, ecolabeling, and pollution prevention tools.

  18. Estimation of radiation dose received by the radiation worker during F-18 FDG injection process

    PubMed Central

    Jha, Ashish Kumar; Zade, Anand; Rangarajan, Venkatesh

    2011-01-01

    Background: The radiation dosimetric literature concerning the medical and non-medical personnel working in nuclear medicine departments are limited, particularly radiation doses received by radiation worker in nuclear medicine department during positron emission tomography (PET) radiopharmaceutical injection process. This is of interest and concern for the personnel. Aim: To measure the radiation dose received by the staff involved in injection process of Fluorine-18 Fluorodeoxyglucose (FDG). Materials and Methods: The effective whole body doses to the radiation workers involved in injections of 1511 patients over a period of 10 weeks were evaluated using pocket dosimeter. Each patient was injected with 5 MBq/kg of F-18 FDG. The F18-FDG injection protocol followed in our department is as follows. The technologist dispenses the dose to be injected and records the pre-injection activity. The nursing staff members then secure an intravenous catheter. The nuclear medicine physicians/residents inject the dose on a rotation basis in accordance with ALARA principle. After the injection of the tracer, the nursing staff members flush the intravenous catheter. The person who injected the tracer then measures the post-injection residual dose in the syringe. Results: The mean effective whole body doses per injection for the staff were the following: Nurses received 1.44±0.22 μSv/injection (3.71±0.48 nSv/MBq), for doctors the dose values were 2.44±0.25 μSv/injection (6.29±0.49 nSv/MBq) and for technologists the doses were 0.61±0.10 μSv/injection (1.58±0.21 nSv/MBq). It was seen that the mean effective whole body dose per injection of our positron emission tomography/computed tomography (PET/CT) staff who were involved in the F18-FDG injection process was maximum for doctors (54.34% differential doses), followed by nurses (32.02% differential doses) and technologist (13.64% differential doses). Conclusion: This study confirms that low levels of radiation dose are

  19. Assessment of annual whole-body occupational radiation exposure in medical practice in Ghana (2000-09).

    PubMed

    Hasford, F; Owusu-Banahene, J; Amoako, J K; Otoo, F; Darko, E O; Emi-Reynolds, G; Yeboah, J; Arwui, C C; Adu, S

    2012-05-01

    Occupational exposure to radiation in medical practice in Ghana has been analysed for a 10-y period between 2000 and 2009. Monitored dose data in the medical institution in Ghana from the Radiation Protection Institute's database were extracted and analysed in terms of three categories: diagnostic radiology, radiotherapy and nuclear medicine. One hundred and eighty medical facilities were monitored for the 10-y period, out of which ~98% were diagnostic radiology facilities. Only one nuclear medicine and two radiotherapy facilities have been operational in the country since 2000. During the 10-y study period, monitored medical facilities increased by 18.8%, while the exposed workers decreased by 23.0%. Average exposed worker per entire medical institution for the 10-y study period was 4.3. Annual collective dose received by all the exposed workers reduced by a factor of 4 between 2000 and 2009. This is seen as reduction in annual collective doses in diagnostic radiology, radiotherapy and nuclear medicine facilities by ~76, ~72 and ~55%, respectively, for the 10-y period. Highest annual collective dose of 601.2 man mSv was recorded in 2002 and the least of 142.6 man mSv was recorded in 2009. Annual average values for dose per institution and dose per exposed worker decreased by 79 and 67.6%, respectively between 2000 and 2009. Average dose per exposed worker for the 10-y period was least in radiotherapy and highest in diagnostic radiology with values 0.14 and 1.05 mSv, respectively. Nuclear medicine however recorded average dose per worker of 0.72 mSv. Correspondingly, range of average effective doses within the diagnostic radiology, radiotherapy and nuclear medicine facilities were 0.328-2.614, 0.383-0.728 and 0.448-0.695 mSv, respectively. Throughout the study period, an average dose per medical institution of 3 mSv and an average dose per exposed worker of 0.69 mSv were realised. Exposed workers in diagnostic radiology primarily received most of the individual

  20. Annual report on the administration of the Radiation Control for Health and Safety Act of 1968, Public Law 90-602, (1988), April 1, 1989. Annual report

    SciTech Connect

    Not Available

    1989-04-01

    The Secretary of Health and Human Services is required by Subpart 3, Part F of Title III of the Public Health Service Act; 42 USC 263b et seq. (Public Law 90-602) to submit an annual report to the President for transmittal to the Congress on or before April 1 on the administration of the Radiation Control for Health and Safety Act. The detailed information required in the report is outlined in Section 360D of the Public Health Service Act. The Food and Drug Administration, through its Center for Devices and Radiological Health, is responsible for the day-to-day administration of the Radiation Control for Health and Safety Act of 1968. The report provides a summary of the operations of the Center in carrying out that responsibility for calendar year 1988. In reviewing the operations of the Center for Devices and Radiological Health as reported in the document, it should be kept in mind that the day-to-day administration of the Act is only part of the Center's function. Other responsibilities include the administration and enforcement of the 1976 Medical Device Amendments to the Federal Food, Drug, and Cosmetic Act (not covered in the report).

  1. Radiation-resistant Macrococcus caseolyticus (A) isolated from radiation-processed semidried prawns.

    PubMed

    Karani, Manisha; Shashidhar, Ravindranath; Kakatkar, Aarti; Gautam, Raj Kamal; Sukhi, Shibani; Pansare-Godambe, Lipika; Bandekar, Jayant

    2015-01-01

    A radiation-resistant bacterial isolate from gamma-radiation-processed (5 kGy) semidried prawns was identified as a new strain of Macrococcus caseolyticus and was designated as M. caseolyticus (A) on the basis of morphological and biochemical characterization and 16S rRNA sequencing. DNA-DNA hybridization studies with M. caseolyticus DSM 20597(T) further confirmed the isolate as M. caseolyticus. Major fatty acids present in M. caseolyticus (A) were C14:0, C16:1ω11c, and C18:1ω9c, whereas C15:0anteiso, C16:0iso, and C18:0iso were absent. The closest match for the isolate, as per fatty acid methyl ester analysis, was M. caseolyticus DSM 20597(T). However, the similarity index was significantly low (0.112), which indicates that the isolate could be a new strain of M. caseolyticus. The decimal reduction dose (D10) for M. caseolyticus (A), M. caseolyticus JCSC5402, and Staphylococcus aureus MTCC96 was 1.18, 0.607, and 0.19 kGy, respectively. This is the first report on radiation resistance of M. caseolyticus. Macrococcus caseolyticus (A) is more resistant to gamma and UV radiation stress than are M. caseolyticus JCSC5402 and S. aureus MTCC96; however, it is sensitive to heat as well as desiccation stress. PMID:25515772

  2. Radiative and collisional processes in CNA 2Π i

    NASA Astrophysics Data System (ADS)

    Halpern, Joshua B.; Huang, Yuhui; Titarchuk, Tatiana

    1996-02-01

    In the last four years we have carried out a number of studies on the radiative and collisional processes in theA 2Π i state of CN. Many of these of interest to those studying planetary atmospheres, comets and solar spectra are summarized in this paper. Data for CNA 2Π i fluorescence lifetimes and quenching rates, and collisional energy transfer between CNA 2Π i andX 2∑+ are reported. Detailed comparisons and a discussion of the results may be found in several already published papers.

  3. Annual Conference on Nuclear and Space Radiation Effects, Gatlinburg, TN, July 18-21, 1983, Proceedings

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Topics discussed include radiation effects in devices; the basic mechanisms of radiation effects in structures and materials; radiation effects in integrated circuits; spacecraft charging and space radiation effects; hardness assurance for devices and systems; and radiation transport, energy deposition and charge collection. Papers are presented on the mechanisms of small instabilities in irradiated MOS transistors, on the radiation effects on oxynitride gate dielectrics, on the discharge characteristics of a simulated solar cell array, and on latchup in CMOS devices from heavy ions. Attention is also given to proton upsets in orbit, to the modeling of single-event upset in bipolar integrated circuits, to high-resolution studies of the electrical breakdown of soil, and to a finite-difference solution of Maxwell's equations in generalized nonorthogonal coordinates.

  4. Processes for quality improvements in radiation oncology clinical trials.

    PubMed

    FitzGerald, T J; Urie, Marcia; Ulin, Kenneth; Laurie, Fran; Yorty, Jeffrey; Hanusik, Richard; Kessel, Sandy; Jodoin, Maryann Bishop; Osagie, Gani; Cicchetti, M Giulia; Pieters, Richard; McCarten, Kathleen; Rosen, Nancy

    2008-01-01

    Quality assurance in radiotherapy (RT) has been an integral aspect of cooperative group clinical trials since 1970. In early clinical trials, data acquisition was nonuniform and inconsistent and computational models for radiation dose calculation varied significantly. Process improvements developed for data acquisition, credentialing, and data management have provided the necessary infrastructure for uniform data. With continued improvement in the technology and delivery of RT, evaluation processes for target definition, RT planning, and execution undergo constant review. As we move to multimodality image-based definitions of target volumes for protocols, future clinical trials will require near real-time image analysis and feedback to field investigators. The ability of quality assurance centers to meet these real-time challenges with robust electronic interaction platforms for imaging acquisition, review, archiving, and quantitative review of volumetric RT plans will be the primary challenge for future successful clinical trials. PMID:18406943

  5. Investigation of the Geokinetics horizontal in situ oil-shale-retorting process. Fourth annual report, 1980

    SciTech Connect

    Hutchinson, D.L.

    1981-03-01

    The Geokinetics in situ shale oil project is a cooperative venture between Geokinetics Inc. and the US Department of Energy. The objective is to develop a true in situ process for recovering shale oil using a fire front moving in a horizontal direction. The project is being conducted at a field site, Kamp Kerogen, located 70 miles south of Vernal, Utah. This Fourth Annual Report covers work completed during the calendar year 1980. During 1980 one full-size retort was blasted. Two retorts, blasted the previous year, were burned. A total of 4891 barrels of oil was produced during the year.

  6. Occupational radiation exposure at commercial nuclear power reactors and other facilities 1995: Twenty-eighth annual report. Volume 17

    SciTech Connect

    Thomas, M.L.; Hagemeyer, D.

    1997-01-01

    This report summarizes the occupational exposure data that are maintained in the US Nuclear Regulatory Commission`s (NRC) Radiation Exposure Information and Reporting System (REIRS). The bulk of the information contained in the report was compiled from the 1995 annual reports submitted by six of the seven categories of NRC licensees subject to the reporting requirements of 10 CFR 20.2206. Since there are no geologic repositories for high-level waste currently licensed, only six categories will be considered in this report. In 1995, the annual collective dose per reactor for light water reactor licensees (LWRs) was 199 person-cSv (person-rem). This is the same value that was reported for 1994. The annual collective dose per reactor for boiling water reactors (BWRs) was 256 person-cSv (person-rem) and, for pressurized water reactors (PWRs), it was 170 person-cSv (person-rem). Analyses of transient worker data indicate that 17,153 individuals completed work assignments at two or more licensees during the monitoring year. The dose distributions are adjusted each year to account for the duplicate reporting of transient workers by multiple licensees. In 1995, the average measurable dose calculated from reported data was 0.26 cSv (rem). The corrected dose distribution resulted in an average measurable dose of 0.32 cSv (rem).

  7. Modeling of clouds and radiation for developing parameterizations for general circulation models. Annual report, 1994

    SciTech Connect

    1994-12-31

    We are using a hierarchy of numerical models of cirrus and stratus clouds and radiative transfer to improve the reliability of general circulation models. Our detailed cloud microphysical model includes all of the physical processes believed to control the lifecycle of liquid and ice clouds in the troposphere. In our one-dimensional cirrus studies, we find that the ice crystal number and size in cirrus clouds are not very sensitive to the number of condensation nuclei which are present. We have compared our three-dimensional meoscale simulations of cirrus clouds with radar, lidar satellite and other observations of water vapor and cloud fields and find that the model accurately predicts the characteristics of a cirrus cloud system. The model results reproduce several features detected by remote sensing (lidar and radar) measurements, including the appearance of the high cirrus cloud at about 15 UTC and the thickening of the cloud at 20 UTC. We have developed a new parameterizations for production of ice crystals based on the detailed one-dimensional cloud model, and are presently testing the parameterization in three-dimensional simulations of the FIRE-II November 26 case study. We have analyzed NWS radiosonde humidity data from FIRE and ARM and found errors, biases, and uncertainties in the conversion of the sensed resistance to humidity.

  8. CIRRPC: Committee on Interagency Radiation Research and Policy Coordination. Eighth annual report

    SciTech Connect

    Young, A.L.

    1992-12-01

    CIRRPC`s eighth year was marked by the completion of several CIRRPC projects, including: An independent study on the possible health effects of extremely low-frequency electric and magnetic fields; a report evaluating the uncertainties identified in a National Academy of Sciences (NAS) report on the biological effects of ionizing radiation and their impact on the report`s application to Federal risk assessment; an analysis of the use of two reports on radiation risk assessment from NAS and the United Nations; and an update of Part 11 of ORAU`s radiation protection fact sheets, a compilation of major US radiation protection standards and guides. CIRRPC also sponsored a workshop on internal dosimetry and provided financial support to the 1991 Health Physics Society Summer School on the biological basis of radiation protection practice. The program highlights are briefly described in this report.

  9. Processability improvement of polyolefins through radiation-induced branching

    NASA Astrophysics Data System (ADS)

    Cheng, Song; Phillips, Ed; Parks, Lewis

    2010-03-01

    Radiation-induced long-chain branching for the purpose of improving melt strength and hence the processability of polypropylene (PP) and polyethylene (PE) is reviewed. Long-chain branching without significant gel content can be created by low dose irradiation of PP or PE under different atmospheres, with or without multifunctional branching promoters. The creation of long-chain branching generally leads to improvement of melt strength, which in turn may be translated into processability improvement for specific applications in which melt strength plays an important role. In this paper, the changes of the melt flow rate and the melt strength of the irradiated polymer and the relationship between long-chain branching and melt strength are reviewed. The effects of the atmosphere and the branching promoter on long-chain branching vs. degradation are discussed. The benefits of improved melt strength on the processability, e.g., sag resistance and strain hardening, are illustrated. The implications on practical polymer processing applications such as foams and films are also discussed.

  10. Quantization effects in radiation spectroscopy based on digital pulse processing

    SciTech Connect

    Jordanov, V. T.; Jordanova, K. V.

    2011-07-01

    Radiation spectra represent inherently quantization data in the form of stacked channels of equal width. The spectrum is an experimental measurement of the discrete probability density function (PDF) of the detector pulse heights. The quantization granularity of the spectra depends on the total number of channels covering the full range of pulse heights. In analog pulse processing the total number of channels is equal to the total digital values produced by a spectroscopy analog-to-digital converter (ADC). In digital pulse processing each detector pulse is sampled and quantized by a fast ADC producing certain number of quantized numerical values. These digital values are linearly processed to obtain a digital quantity representing the peak of the digitally shaped pulse. Using digital pulse processing it is possible to acquire a spectrum with the total number of channels greater than the number of ADC values. Noise and sample averaging are important in the transformation of ADC quantized data into spectral quantized data. Analysis of this transformation is performed using an area sampling model of quantization. Spectrum differential nonlinearity (DNL) is shown to be related to the quantization at low noise levels and small number of averaged samples. Theoretical analysis and experimental measurements are used to obtain the condition to minimize the DNL due to quantization. (authors)

  11. NREL Solar Radiation Resource Assessment Project: Status and outlook. FY 1991 annual progress report

    SciTech Connect

    Renne, D.; Riordan, C.; Maxwell, E.; Stoffel, T.; Marion, B.; Rymes, M.; Wilcox, S.; Myers, D.

    1992-05-01

    This report summarizes the activities and accomplishments of NREL`s Solar Radiation Resource Assessment Project during fiscal year 1991. Currently, the primary focus of the SRRAP is to produce a 1961--1990 National Solar Radiation Data Base, providing hourly values of global horizontal, diffuse, and direct normal solar radiation at approximately 250 sites around the United States. Because these solar radiation quantities have been measured intermittently at only about 50 of these sites, models were developed and applied to the majority of the stations to provide estimates of these parameters. Although approximately 93% of the data base consists of modeled data this represents a significant improvement over the SOLMET/ERSATZ 1952--1975 data base. The magnitude and importance of this activity are such that the majority of SRRAP human and financial in many other activities, which are reported here. These include the continued maintenance of a solar radiation monitoring network in the southeast United States at six Historically Black Colleges and Universities (HBCU`s), the transfer of solar radiation resource assessment technology through a variety of activities, participation in international programs, and the maintenance and operation of NREL`s Solar Radiation Research Laboratory. 17 refs.

  12. A genipin-gelatin gel dosimeter for radiation processing

    NASA Astrophysics Data System (ADS)

    Davies, J. B.; Bosi, S. G.; Baldock, C.

    2012-08-01

    Genipin, a fruit extract from Gardenia jasminoides Ellis, forms cross-links in solutions of gelatin, to form a blue hydrogel that bleaches quantitatively upon irradiation and the colour change can be measured with a spectrophotometer. With the addition of sulphuric acid this dosimeter is sufficiently sensitive for quality assurance of radiotherapy level dosimetry. Without sulphuric acid the gel has a reduced sensitivity and responds linearly with dose between 100 and 1000 Gy, making it potentially useful as a dosimeter for radiation processing applications such as the phytosanitary irradiation treatment of food. We investigated the dose response characteristics of this new formulation and found that the darker gels are more sensitive to dose and have a reduced uncertainty.

  13. Boundary effects on radiative processes of two entangled atoms

    NASA Astrophysics Data System (ADS)

    Arias, E.; Dueñas, J. G.; Menezes, G.; Svaiter, N. F.

    2016-07-01

    We analyze radiative processes of a quantum system composed by two identical two-level atoms interacting with a massless scalar field prepared in the vacuum state in the presence of perfect reflecting flat mirrors. We consider that the atoms are prepared in a stationary maximally entangled state. We investigate the spontaneous transitions rates from the entangled states to the collective ground state induced by vacuum fluctuations. In the empty-space case, the spontaneous decay rates can be enhanced or inhibited depending on the specific entangled state and changes with the distance between the atoms. Next, we consider the presence of perfect mirrors and impose Dirichlet boundary conditions on such surfaces. In the presence of a single mirror the transition rate for the symmetric state undergoes a slight reduction, whereas for the antisymmetric state our results indicate a slightly enhancement. Finally, we investigate the effect of multiple reflections by two perfect mirrors on the transition rates.

  14. Crosstalk between telomere maintenance and radiation effects: A key player in the process of radiation-induced carcinogenesis

    PubMed Central

    Shim, Grace; Ricoul, Michelle; Hempel, William M.; Azzam, Edouard I.; Sabatier, Laure

    2014-01-01

    It is well established that ionizing radiation induces chromosomal damage, both following direct radiation exposure and via non-targeted (bystander) effects, activating DNA damage repair pathways, of which the proteins are closely linked to telomeric proteins and telomere maintenance. Long-term propagation of this radiation-induced chromosomal damage during cell proliferation results in chromosomal instability. Many studies have shown the link between radiation exposure and radiation-induced changes in oxidative stress and DNA damage repair in both targeted and non-targeted cells. However, the effect of these factors on telomeres, long established as guardians of the genome, still remains to be clarified. In this review, we will focus on what is known about how telomeres are affected by exposure to low- and high-LET ionizing radiation and during proliferation, and will discuss how telomeres may be a key player in the process of radiation-induced carcinogenesis. PMID:24486376

  15. ESR/alanine dosimetry applied to radiation processing

    NASA Astrophysics Data System (ADS)

    Mosse, D. C.

    The radiation processing of food products is specified in terms of absorbed dose, and processing quality is assessed on the basis of absorbed dose measurements. The validity of process quality control is highly dependent on the quality of the measurements and associated instrumentation; in this respect, dosimetry calibration by an Organization with official status provides an essential guarantee of validity to the quality control steps taken. The Laboratoire de Métrologie des Rayonnements Ionisants (L.M.R.I.) is the primary standards and evaluation laboratory approved by the Bureau National de Métrologie (B.N.M.), which is the French National Bureau of Standards. The LMRI implements correlation procedures in response to the various requirements which arise in connection with high doses and doserates. Such procedures are mainly based on ESR/alanine spectrometry, a dosimetry technique ideally suited to that purpose. Dosemeter geometry and design are tailored to operating conditions. "Photon" dosemeters consist of a detector material in powder or compacted form, and a wall with thickness and chemical composition consistent with the application. "Electron" dosemeters have a detector core of compacted alanine with thickness down to a few tenths of a millimeter. The ESR/alanine dosimetry technique, developed at LMRI is a flexible, reliable and accurate tool which effectively meets the various requirements arising in the field of reference dosimetry, where high doses and doserates are involved.

  16. SERI Solar Radiation Resource Assessment Project: Fiscal Year 1990 Annual Progress Report

    SciTech Connect

    Riordan, C; Maxwell, E; Stoffel, T; Rymes, M; Wilcox, S

    1991-07-01

    The purpose of the Solar Radiation Resource Project is to help meet the needs of the public, government, industry, and utilities for solar radiation data, models, and assessments as required to develop, design, deploy, and operate solar energy conversion systems. The project scientists produce information on the spatial (geographic), temporal (hourly, daily, and seasonal), and spectral (wavelength distribution) variability of solar radiation at different locations in the United States. Resources committed to the project in FY 1990 supported about four staff members, including part-time administrative support. With these resources, the staff must concentrate on solar radiation resource assessment in the United States; funds do not allow for significant efforts to respond to a common need for improved worldwide data. 34 refs., 21 figs., 6 tabs.

  17. 21 CFR 179.39 - Ultraviolet radiation for the processing and treatment of food.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ultraviolet radiation for the processing and treatment of food. 179.39 Section 179.39 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING OF FOOD Radiation and Radiation Sources § 179.39...

  18. Thromboxane-mediated injury following radiation. Annual report, 1 September 1984-31 August 1985

    SciTech Connect

    Kot, P.A.

    1985-08-31

    The hypothesis under investigation is that moderate levels of radiation exposure result in endothelial and other tissue damage which, in turn, increases in vivo synthesis of thromboxane A2 (TXA2). The observations indicate that the sources of the radiation-induced increases in TXB2 excretion are diverse, involving organs of both the thorax and upper abdomen. This conclusion is based on the attenuation in the radiation-induced increase in TXB2 excretion seen four hours after 20.0-Gy gamma irradiation with either the thorax or abdomen shielded. An isolated perfused rat kidney model was developed to determine if the kidneys contribute to the altered cyclooxygenase product release. Urine from the irradiated isolated kidney system showed an elevated excretion of TXB2, PGE2, and 6KPGFla compared to kidneys from sham-irradiated animals. Whole-body irradiation of rats also increased pulmonary release of TXB2 four hours after exposure. The data show that in vivo release of TXB2 involves more than one organ system and as a result, the use of TXB2 as a biological dosimeter requires knowledge as to the organ systems that were irradiated. These data also suggest that regional release of TXB2 varies and as such may provide a means of evaluating regional radiation injury. The results of the past year show that radiation can alter vascular reactivity to a cyclooxygenase product mimic and that this arachidonate metabolite release is increased following radiation exposure.

  19. UV RADIATION EFFECTS ON MICROBES AND MICROBIAL PROCESSES

    EPA Science Inventory

    The ultraviolet (UV) region of solar radiation is defined as wavelengths in the range of 200 to 400 nm. In contrast to visible radiation (400 - 800 nm), which has a well-defined role as the energy source for most of the Earth's primary production, the effects of UV radiation on b...

  20. Proceedings of the Efficient Separations and Processing Cross-Cutting Program Annual Technical Exchange Meeting

    SciTech Connect

    1995-02-01

    This document contains summaries of technology development presented at the 1995 Efficient Separations and Processing Cross-Cutting Program (ESP) Annual Technical Exchange Meeting. The ESP is sponsored by the US Department of Energy`s Office of Environmental Management (EM), Office of Technology Development. The meeting is held annually to promote a free exchange of ideas among technology developers, potential users (for example, EM focus areas), and other interested parties within EM. During this meeting, developers of ESP-funded technologies describe the problems and needs addressed by their technologies; the technical approach, accomplishments, and resolution of issues; the strategy and schedule for commercialization; and evolving potential applications. Presenters are asked to address the following areas: Target waste management problem, waste stream, or data need; scientific background and technical approach; technical accomplishments and resolution of technical issues; schedule and strategy for commercializing and implementing the technology or acquiring needed data; potential alternate applications of the technology or data, including outside of DOE/EM. The meeting is not a program review of the individual tasks or subtasks; but instead focuses on the technical aspects and implementation of ESP-sponsored technology or data. The meeting is also attended by members of the ESP Technical Review Team, who have the opportunity at that time to review the ESP as a whole.

  1. 50 CFR 648.96 - Monkfish annual adjustment process and framework specifications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... meet on or before November 15 of each year to develop target TACs for the upcoming fishing year in.... (b) Annual Adjustment Procedures—(1) Annual Target TACs for FY 2007 through FY 2009—(i) NFMA. The annual target TAC for the NFMA is 5,000 mt for FY 2007 through FY 2009, unless otherwise recommended...

  2. Processing of Atmospheric Organic Matter by California Radiation Fogs

    NASA Astrophysics Data System (ADS)

    Collett, J. L.; Youngster, S. B.; Lee, T.; Chang, H.; Herckes, P.

    2005-12-01

    In many environments, organic compounds account for a significant fraction of fine particle mass. Because the lifetimes of accumulation mode aerosol particles are governed largely by interactions with clouds, it is important to understand how organic aerosol particles are processed by clouds and fogs. Recently we have examined the organic composition of radiation fogs in central California as well as how these fogs process organic aerosol particles and soluble organic trace gases. Observations indicate that organic matter is a significant component of the fog droplets, comprising approximately one-third of the total solute mass concentration. Concentrations of total organic carbon (TOC) range from approximately 2 to 41 ppmC. Approximately three-fourths of organic matter is typically found in solution as dissolved organic carbon (DOC). A variety of efforts have been made to characterize the composition of the fog organic matter, including analyses by GC/MS, HPLC, IC, NMR and IR. The most abundant species are typically low molecular weight carboxylic acids, small carbonyls and dicarbonyls, and sugar anhydrides. These species have been observed collectively to account for roughly 20-30 percent of the fog DOC. Dicarboxylic acids, frequently used as model compounds for organic CCN, typically account for only a few percent of the organic carbon, with oxalic acid the most important contributor. A significant portion of the fog DOC appears to be comprised of high molecular weight compounds (> 500 Da). Analyses also reveal the presence of organic molecular markers associated with particles produced by various combustion processes. Comparisons of pre-fog and interstitial aerosol samples reveal differences in the relative particle scavenging efficiencies of the fog drops between organic and elemental carbon and between different types of organic carbon. Measurements using a two-stage fog water collector reveal that organic matter tends to be enriched in smaller fog droplets

  3. Economic evaluation of radiation processing in urban solid wastes treatment

    NASA Astrophysics Data System (ADS)

    Carassiti, F.; Lacquaniti, L.; Liuzzo, G.

    During the last few years, quite a number of studies have been done, or are still in course, on disinfection of urban liquid wastes by means of ionizing radiations. The experience gained by SANDIA pilot plant of irradiation on dried sewage sludge, together with the recently presented conceptual design of another plant handling granular solids, characterized by high efficiency and simple running, have shown the possibility of extending this process to the treatment of urban solid wastes. As a matter of fact, the problems connected to the pathogenic aspects of sludge handling are often similar to those met during the disposal of urban solid wastes. This is even more so in the case of their reuse in agriculture and zootechny. The present paper introduces the results of an analysis carried out in order to evaluate the economical advantage of inserting irradiation treatment in some process scheme for management of urban solid wastes. Taking as an example a comprehensive pattern of urban solid wastes management which has been analysed and estimated economically in previous works, we first evaluated the extra capital and operational costs due to the irradiation and then analysed economical justification, taking into account the increasing commercial value of the by-products.

  4. Advances in Linac-Based Technology for Industrial Radiation Processing

    NASA Astrophysics Data System (ADS)

    McKeown, Joseph

    1997-04-01

    Experience with the Industrial Materials Processing Electron Linear Accelerator, IMPELA, over 30,000 hours of 50 kW operation is reported for three irradiators, two of which are in commercial service. Operations are sufficiently mature that research is now concentrated on split beams, photon conversion, dose monitoring, beam scanning, new shielding designs and QA controls. The efficacy of increasing the incident electron energy on bremsstrahlung converters to 7.5 MeV, as proposed by an IAEA committee, is examined experimentally on an IMPELA accelerator over the energy range 7 MeV to 11 MeV to evaluate conversion efficiency, activation of machine components, converter engineering and the activation of red meat. Above 8 MeV the radioactive isotopes ^38Cl and ^24Na, formed primarily by neutrons produced in a tantalum converter, were clearly identified in the meat, while above 10.5 MeV the radiation from ^13N becomes dominant. Implications for the practicality of processing other high density products are discussed.

  5. Image processing pipeline for synchrotron-radiation-based tomographic microscopy.

    PubMed

    Hintermüller, C; Marone, F; Isenegger, A; Stampanoni, M

    2010-07-01

    With synchrotron-radiation-based tomographic microscopy, three-dimensional structures down to the micrometer level can be visualized. Tomographic data sets typically consist of 1000 to 1500 projections of 1024 x 1024 to 2048 x 2048 pixels and are acquired in 5-15 min. A processing pipeline has been developed to handle this large amount of data efficiently and to reconstruct the tomographic volume within a few minutes after the end of a scan. Just a few seconds after the raw data have been acquired, a selection of reconstructed slices is accessible through a web interface for preview and to fine tune the reconstruction parameters. The same interface allows initiation and control of the reconstruction process on the computer cluster. By integrating all programs and tools, required for tomographic reconstruction into the pipeline, the necessary user interaction is reduced to a minimum. The modularity of the pipeline allows functionality for new scan protocols to be added, such as an extended field of view, or new physical signals such as phase-contrast or dark-field imaging etc. PMID:20567088

  6. Process of coping with intracavity radiation treatment for gynecologic cancer

    SciTech Connect

    Nail, L.M.D.

    1985-01-01

    The purpose of this study was to describe the process of coping with the experience of receiving intracavity radiation treatment (ICR) for gynecologic cancer. Data were collected on the outcomes of coping, emotion (Profile of Mood States) and level of function (Sickness Impact Profile), and symptom severity and upset the evening before, during, the day after, and 1 to 2 weeks after treatment. The subjects (N = 28) had a mean age of 52 years, 39% were employed full-time, 56% had occupations as manual workers, 57% had completed 12 or more years of education, and 68% were married or widowed. The treatment required the subjects to be hospitalized on complete bedrest with radiation precautions for an average of 48 hours. Intrauterine devices were used to treat 18 subjects and vaginal applications were used to treat 10 subjects. Negative mood and level of disruption in function were generally low. Repeated measures ANOVA showed no change in negative mood over time while the change in function was attributable to the increase in disruption during treatment. Utilization of affective coping strategies and problem-oriented coping strategies was positively correlated with negative mood and disruption in function over the points of measurement. The results indicate that subjects tolerated ICR well and rapidly resumed usual function following discharge from the hospital, despite the persistence of some symptoms 1 to 2 weeks after treatment. The positive association between the utilization of coping strategies and negative outcomes of coping suggests a need to examine the measurement of coping strategies and consider the possibility that these actions represent a response to a stressful situation rather than a method of dealing with the situation.

  7. Processes forming and sustaining Saturn's proton radiation belts

    NASA Astrophysics Data System (ADS)

    Kollmann, P.; Roussos, E.; Paranicas, C.; Krupp, N.; Haggerty, D. K.

    2013-01-01

    Saturn's proton radiation belts extend over the orbits of several moons that split this region of intense radiation into several distinct belts. Understanding their distribution requires to understand how their particles are created and evolve. High-energy protons are thought to be dominantly produced by cosmic ray albedo neutron decay (CRAND). The source of the lower energies and the role of other effects such as charge exchange with the gas originating from Enceladus is still an open question. There is also no certainty so far if the belts exist independently from each other and the rest of the magnetosphere or if and how particles are exchanged between these regions. We approach these problems by using measurements acquired by the MIMI/LEMMS instrument onboard the Cassini spacecraft. Protons in the range from 500 keV to 40 MeV are considered. Their intensities are averaged over 7 years of the mission and converted to phase space densities at constant first and second adiabatic invariant. We reproduce the resulting radial profiles with a numerical model that includes radial diffusion, losses from moons and interactions with gas, and a phenomenological source. Our results show that the dominating effects away from the moon sweeping corridors are diffusion and the source, while interactions with gas are secondary. Based on a GEANT4 simulation of the interaction of cosmic rays with Saturn's rings, we conclude that secondary particles produced within the rings can only account for the high-energy part of the source. A comparison with the equivalent processes within Earth's atmosphere shows that Saturn's atmosphere can contribute to the production of the lower energies and might be even dominating at the higher energies. Other possibilities to supply the belts and exchange particles between them, as diffusion and injections from outside the belts, or stripping of ENAs, can be excluded.

  8. Occupational radiation exposure at commercial nuclear power reactors and other facilities 1994. Twenty-seventh annual report

    SciTech Connect

    Thomas, M.L.; Hagemeyer, D.

    1996-01-01

    This report summarizes the occupational exposure data that are maintained in the U.S. Nuclear Regulatory Commission`s (NRC) Radiation Exposure Information and Reporting System (REIRS). Annual reports for 1994 were received from a total of 303 NRC licensees, of which 109 were operators of nuclear power reactors in commercial operation. Compilations of the reports submitted by the 303 licensees indicated that 152,028 individuals were monitored, 79,780 of whom received a measurable dose. The collective dose incurred by these individuals was 24,740 person-cSv (person-rem){sup 2} which represents a 15% decrease from the 1993 value. The number of workers receiving a measurable dose also decreased, resulting in the average measurable dose of 0.31 cSv (rem) for 1994. The average measurable dose is defined to be the total collective dose (TEDE) divided by the number of workers receiving a measurable dose. These figures have been adjusted to account for transient reactor workers. In 1994, the annual collective dose per reactor for light water reactor licensees (LWRs) was 198 person-cSv (person-rem). This represents a 18% decrease from the 1993 value of 242 person-cSv (person-rem). The annual collective dose per reactor for boiling water reactors (BWRs) was 327 person-cSv (person-rem) and, for pressurized water reactors (PWRs), it was 131 person-cSv (person-rem). Analyses of transient worker data indicate that 18,178 individuals completed work assignments at two or more licensees during the monitoring year. The dose distributions are adjusted each year to account for the duplicate reporting of transient workers by multiple licensees. In 1994, the average measurable dose calculated from reported data was 0.28 cSv (rem). The corrected dose distribution resulted in an average measurable dose of 0.31 cSv (rem).

  9. Effects of clouds on the Earth radiation budget; Seasonal and inter-annual patterns

    NASA Technical Reports Server (NTRS)

    Dhuria, Harbans L.

    1992-01-01

    Seasonal and regional variations of clouds and their effects on the climatological parameters were studied. The climatological parameters surface temperature, solar insulation, short-wave absorbed, long wave emitted, and net radiation were considered. The data of climatological parameters consisted of about 20 parameters of Earth radiation budget and clouds of 2070 target areas which covered the globe. It consisted of daily and monthly averages of each parameter for each target area for the period, Jun. 1979 - May 1980. Cloud forcing and black body temperature at the top of the atmosphere were calculated. Interactions of clouds, cloud forcing, black body temperature, and the climatological parameters were investigated and analyzed.

  10. Pulsed combustion process for black liquor gasification. Second annual report, [November 1990--February 1992

    SciTech Connect

    Not Available

    1993-02-01

    This second annual report summarizes the work accomplished during the period November 1990 through February 1992 for DOE Cooperative Agreement No. DE-FC05-90CE40893. The overall project objective is to field test an energy-efficient, innovative black liquor recovery system at a significant industrial scale. This is intended to demonstrate the maturity of the technology in an industrial environment and serve as an example to the industry of the safer and more energy-efficient processing technique. The project structure is comprised of three primary activities: process characterization testing, scale-up hardware development, and field testing. The objective of the process characterization testing was to resolve key technical issues regarding the black liquor recovery process that were identified during earlier laboratory verification tests. This was intended to provide a sound engineering data base for the design, construction and testing of a nominal 1.0 TPH integrated black liquor recovery gasifier. The objective of the scale-up hardware development effort was to ensure that key hardware components, in particular the pulse heater module, would perform reliably and safely in the field. Finally, the objective of the field test is to develop an industrial data base sufficient to demonstrate the capabilities and performance of the operating system with respect to thermal efficiency, product quality, fuel handling, system control, reliability and cost. These tests are to provide long-term and continuous operating data at a capacity unattainable in the bench-scale apparatus.

  11. Committee on Interagency Radiation Research and Policy Coordination (CIRRPC). Seventh annual report

    SciTech Connect

    Young, A.L.

    1991-06-30

    In 1990--91 CIRRPC`s program included efforts to improve interagency coordination on ionizing radiation risk assessments, a review of the reported health risks to humans from exposure to extremely low- frequency electric and magnetic fields (ELF/EMF), and increased coordination with national and international organizations such as NCRP and ICRP.

  12. ANNUAL PROGRESS REPORT. RADIATION EFFECTS ON SORPTION AND MOBILIZATION OF RADIONUCLIDES DURING TRANSPORT THROUGH THE GEOSPHERE

    EPA Science Inventory

    This research program has been aimed at the understanding of radiation effects on the sorption/desorption and ion exchange capacity of radionuclides in two major groups of geologic materials, clays and zeolites. The experiments are designed for investigating the effects of ionizi...

  13. 1985 Annual Conference on Nuclear and Space Radiation Effects, 22nd, Monterey, CA, July 22-24, 1985, Proceedings

    NASA Technical Reports Server (NTRS)

    Jones, C. W. (Editor)

    1985-01-01

    Basic mechanisms of radiation effects in structures and materials are discussed, taking into account the time dependence of interface state production, process dependent build-up of interface states in irradiated N-channel MOSFETs, bias annealing of radiation and bias induced positive charges in n- and p-type MOS capacitors, hole removal in thin-gate MOSFETs by tunneling, and activation energies of oxide charge recovery in SOS or SOI structures after an ionizing pulse. Other topics investigated are related to radiation effects in devices, radiation effects in integrated circuits, spacecraft charging and space radiation effects, single-event phenomena, hardness assurance and radiation sources, SGEMP/IEMP phenomena, EMP phenomena, and dosimetry and energy-dependent effects. Attention is given to a model of the plasma wake generated by a large object, gate charge collection and induced drain current in GaAs FETs, simulation of charge collection in a multilayer device, and time dependent dose enhancement effects on integrated circuit transient response mechanisms.

  14. Industrialization of radiation-induced emulsion polymerization ----technological process and its advantages

    NASA Astrophysics Data System (ADS)

    Zhicheng, Zhang; Manwei, Zhang

    1993-07-01

    A technological process for industrialization of radiation induced emulsion polymerization was introduced briefly. A batch process rather than continuous one was adopted in the industrial-scale production. The advantages of radiation induced emulsion polymerization were described in comparison with chemical initiated process.

  15. Processing and characterization of epitaxial GaAs radiation detectors

    NASA Astrophysics Data System (ADS)

    Wu, X.; Peltola, T.; Arsenovich, T.; Gädda, A.; Härkönen, J.; Junkes, A.; Karadzhinova, A.; Kostamo, P.; Lipsanen, H.; Luukka, P.; Mattila, M.; Nenonen, S.; Riekkinen, T.; Tuominen, E.; Winkler, A.

    2015-10-01

    GaAs devices have relatively high atomic numbers (Z=31, 33) and thus extend the X-ray absorption edge beyond that of Si (Z=14) devices. In this study, radiation detectors were processed on GaAs substrates with 110 - 130 μm thick epitaxial absorption volume. Thick undoped and heavily doped p+ epitaxial layers were grown using a custom-made horizontal Chloride Vapor Phase Epitaxy (CVPE) reactor, the growth rate of which was about 10 μm / h. The GaAs p+/i/n+ detectors were characterized by Capacitance Voltage (CV), Current Voltage (IV), Transient Current Technique (TCT) and Deep Level Transient Spectroscopy (DLTS) measurements. The full depletion voltage (Vfd) of the detectors with 110 μm epi-layer thickness is in the range of 8-15 V and the leakage current density is about 10 nA/cm2. The signal transit time determined by TCT is about 5 ns when the bias voltage is well above the value that produces the peak saturation drift velocity of electrons in GaAs at a given thickness. Numerical simulations with an appropriate defect model agree with the experimental results.

  16. Illinois biomass resources: annual crops and residues; canning and food-processing wastes. Preliminary assessment

    SciTech Connect

    Antonopoulos, A A

    1980-06-01

    Illinois, a major agricultural and food-processing state, produces vast amounts of renewable plant material having potential for energy production. This biomass, in the form of annual crops, crop residues, and food-processing wastes, can be converted to alternative fuels (such as ethanol) and industrial chemicals (such as furfural, ethylene, and xylene). The present study provides a preliminary assessment of these Illinois biomass resources, including (a) an appraisal of the effects of their use on both agriculture and industry; (b) an analysis of biomass conversion systems; and (c) an environmental and economic evaluation of products that could be generated from biomass. It is estimated that, of the 39 x 10/sup 6/ tons of residues generated in 1978 in Illinois from seven main crops, about 85% was collectible. The thermal energy equivalent of this material is 658 x 10/sup 6/ Btu, or 0.66 quad. And by fermenting 10% of the corn grain grown in Illinois, some 323 million gallons of ethanol could have been produced in 1978. Another 3 million gallons of ethanol could have been produced in the same year from wastes generated by the state's food-processing establishments. Clearly, Illinois can strengthen its economy substantially by the development of industries that produce biomass-derived fuels and chemicals. In addition, a thorough evaluation should be made of the potential for using the state's less-exploitable land for the growing of additional biomass.

  17. Human genetic marker for resistance to radiations and chemicals. 1998 annual progress report

    SciTech Connect

    Lieberman, H.B.

    1998-06-01

    'The broad objective of the project is to understand the molecular basis for the response of cells to radiations and chemicals, with the pragmatic goal of being able to identify human subpopulations that are exceptionally sensitive to DNA damaging agents. The project focuses on HRAD9, a human orthologue of the fission yeast Schizosaccharomyces pombe gene rad9. S. pombe rad9::ura4+ mutant cells are highly sensitive to ionizing radiation, UV and many chemicals, such as the DNA synthesis inhibitor hydroxyurea. They also lack the ability to delay cycling transiently in S phase or in G2 following a block in DNA replication or after incurring DNA damage, respectively -i.e., they lack checkpoint controls. The attempt by mutant cells to progress through mitosis in the absence of fully intact DNA accounts at least in part for their sensitivity to DNA damaging agents. Cells bearing rad9::ura4+ also aberrantly regulate UVDE, an enzyme that participates in a secondary DNA excision repair pathway. The key role played by S. pombe rad9 in promoting resistance to chemicals and radiations suggests that the evolutionarily conserved human cognate also has important functions in mammals. The first set of aims in this proposal centers on characterizing the structure and expression of HRAD9, to assess structure/function relationships and potentially link protein activity to a specific tissue. The next set of aims focuses on determining the role of HRAD9 in radio/chemoresponsiveness and cancer.'

  18. Fabrication process scale-up and optimization for a boron-aluminum composite radiator

    NASA Technical Reports Server (NTRS)

    Okelly, K. P.

    1973-01-01

    Design approaches to a practical utilization of a boron-aluminum radiator for the space shuttle orbiter are presented. The program includes studies of laboratory composite material processes to determine the feasibility of a structural and functional composite radiator panel, and to estimate the cost of its fabrication. The objective is the incorporation of boron-aluminum modulator radiator on the space shuttle.

  19. Preliminary report of plants and processes for infrared radiation

    SciTech Connect

    Not Available

    1980-04-18

    The industrial uses and unwanted industrial occurrences of infrared radiation were discussed. The physical characteristics of infrared radiation were described. Exposure to infrared radiation was considered for the following industries: chemicals and allied products, contract construction, electrical equipment, fabricated metals, food and related products, furniture and fixtures, instruments, leather products, manufacturing, primary metals, printing and publishing, rubber and plastics, and stone, clay and glass. The extent of employee exposure to infrared radiation depended on wavelength and energy, proximity of worker to source, degree of worker protection with heat shields, clothing, and tinted goggles, and general workplace conditions. The eye was the critical organ due to its limited ability to dissipate the absorbed heat and its sensitivity to elevated intraocular temperatures. The skin was also a primary concern as it has an extensive surface area and is the initial absorber of incident infrared radiation.

  20. Treatment of LW and SW Radiative Processes in a Climate GCM

    NASA Astrophysics Data System (ADS)

    Lacis, A. A.; Oinas, V.

    2010-12-01

    Of the physical processes that convert, transport, and redistribute energy within the climate system, radiation is by far the fastest. Radiation is also the best understood of these physical processes and therefore the most amenable for accurate parameterization. As an illustrative example, we describe the radiative modeling treatment of the LW and SW radiation in the GISS ModelE climate GCM and its comparison to LBL calculated heating and cooling rates, including radiative forcing sensitivity. We also compare and analyze the spectral and height dependence of he radiative forcing sensitivity for the principal greenhouse gases based on 1-D LBL radiative/convective equilibrium calculations. We also describe the ModelE LW flux parameterization to account for multiple scattering effects for LW TOA and BOA fluxes, and the laboratory based parameterization scheme for modeling the relative humidity dependence of aerosol radiative properties for hygroscopic aerosol species.

  1. Application of radiation processing in asia and the pacific region: Focus on malaysia

    NASA Astrophysics Data System (ADS)

    Mohd Dahlan, Khairul Zaman HJ.

    1995-09-01

    Applications of radiation processing in Malaysia and other developing countries in Asia and the Pacific region is increasing as the countries move toward industrialisation. At present, there are more than 85 gamma facilities and 334 electron accelerators in Asia and the Pacific region which are mainly in Japan, Rep. of Korea and China. The main applications which are in the interest of the region are radiation sterilisation of medical products; radiation crosslinking of wire and cable, heat shrinkable film and tube, and foam; radiation curing of surface coatings, printing inks and adhesive; radiation vulcanisation of natural rubber latex; radiation processing of agro-industrial waste; radiation treatment of sewage sludge and municipal waste; food irradiation; tissue grafts and radiation synthesis of bioactive materials.

  2. Selected papers from the Fourth Annual q-bio Conference on Cellular Information Processing.

    PubMed

    Nemenman, Ilya; Faeder, James R; Hlavacek, William S; Jiang, Yi; Wall, Michael E; Zilman, Anton

    2011-10-01

    This special issue consists of 11 original papers that elaborate on work presented at the Fourth Annual q-bio Conference on Cellular Information Processing, which was held on the campus of St John's College in Santa Fe, New Mexico, USA, 11-14 August 2010. Now in its fourth year, the q-bio conference has changed considerably over time. It is now well established and a major event in systems biology. The 2010 conference saw attendees from all continents (except Antarctica!) sharing novel results and participating in lively discussions at both the oral and poster sessions. The conference was oversubscribed and grew to 27 contributed talks, 16 poster spotlights and 137 contributed posters. We deliberately decreased the number of invited speakers to 21 to leave more space for contributed presentations, and the attendee feedback confirmed that the choice was a success. Although the q-bio conference has grown and matured, it has remained true to the original goal of being an intimate and dynamic event that brings together modeling, theory and quantitative experimentation for the study of cell regulation and information processing. Funded in part by a grant from NIGMS and by DOE funds through the Los Alamos National Laboratory Directed Research and Development program, the conference has continued to exhibit youth and vigor by attracting (and partially supporting) over 100 undergraduate, graduate and postdoctoral researchers. The associated q-bio summer school, which precedes the conference each year, further emphasizes the development of junior scientists and makes q-bio a singular event in its impact on the future of quantitative biology. In addition to an increased international presence, the conference has notably diversified its demographic representation within the USA, including increased participation from the southeastern corner of the country. One big change in the conference this year is our new publication partner, Physical Biology. Although we are very

  3. Determinability of inter-annual global and regional climatic changes of the earth radiation budget

    NASA Technical Reports Server (NTRS)

    Ardanuy, P. E.

    1983-01-01

    The degradation characteristics of Earth Radiation Budget (ERB) experiments are examined with reference to the results of recent investigations into the calibration adjustments of the Wide Field of View channels on board the Nimbus 6 and 7 ERB experiments. The mechanisms of degradation are discussed, and changes in the transmissive and reflective properties of radiometers affecting their sensitivities and calibrations are estimated. It is emphasized that in order to observe interannual climate change on a global or a regional scale, calibration adjustments are a necessity.

  4. Processing of atmospheric organic matter by California radiation fogs

    NASA Astrophysics Data System (ADS)

    Collett, Jeffrey L., Jr.; Herckes, Pierre; Youngster, Sarah; Lee, Taehyoung

    2008-03-01

    Considerable effort has been put into characterizing the ionic composition of fogs and clouds over the past twenty-five years. Recently it has become evident that clouds and fogs often contain large concentrations of organic material as well. Here we report findings from a series of studies examining the organic composition of radiation fogs in central California. Organic compounds in these fogs comprise a major fraction of total solute mass, with total organic carbon sometimes reaching levels of several tens of mg/L. This organic matter is comprised of a wide variety of compounds, ranging from low molecular weight organic acids to high molecular weight compounds with molecular masses approaching several hundred to a thousand g/mole. The most abundant individual compounds are typically formic acid, acetic acid, and formaldehyde. High concentrations are also observed of some dicarboxylic acids (e.g., oxalate) and dicarbonyls (e.g., glyoxal and methylglyoxal) and of levoglucosan, an anhydrosugar characteristically emitted by biomass combustion. Many other compounds have been identified in fog water by GC/MS, including long chain n-alkanoic acids, n-alkanes, PAH, and others, although these compounds typically comprise a total of only a few percent of fog TOC. Measurements of fog scavenging of organic and elemental carbon reveal preferential scavenging of organic carbon. Tracking of individual organic compounds utilized as source type markers suggests the fogs differentially scavenge carbonaceous particles from different source types, with more active processing of wood smoke than vehicle exhaust. Observations of high deposition velocities of fog-borne organic carbon, in excess of 1 cm/s, indicate that fogs in the region represent an important mechanism for cleansing the atmosphere of pollution.

  5. Fiscal Year 1993 annual report for the Bubble Membrane Radiator Project

    SciTech Connect

    Guenther, R.J.; Pauley, K.A.; Antoniak, Z.I.; Sambrook, J.M.

    1994-02-01

    This report summarizes the activities conducted on the Bubble Membrane Radiator (BMR) Project during Fiscal Year (FY) 1993 at the Pacific Northwest Laboratory (PNL) in Richland, Washington. Funding for this work has been provided by the National Aeronautics and Space Administration (NASA), Lyndon B. Johnson Space Center (JSC), Crew and Thermal Sciences Division. The BMR Project was initiated at PNL in March 1988 to continue development of promising thermal management concepts for space applications. In FY 1992 work was refocused from the BMR to fabrication and testing of ultralight fabric reflux tubes (UFRT) because of progress in this area and the desire to incorporate this concept in thermal management for a lunar colony. Development, optimization, and testing of UFRTs continued in FY 1993 under five tasks. Task B, Radiative Properties, and Task D, Development of Tough Metal UFRT Technology, were initiated in FY 1992 and completed this year. Three additional tasks were initiated: Task 1, Fabricate Tubes; Task 2, Heat Transfer Optimization; and Task 3, Analyses Follow-On. A summary of the activities under these tasks and conclusions are provided below.

  6. Community Radiation Monitoring Program annual report, October 1, 1989--September 30, 1990

    SciTech Connect

    Cooper, E.N.; McArthur, R.D.

    1991-07-01

    The events of FY 1990 indicate that another successful year in the evolution of the Community Radiation Monitoring Program is in the books. The agencies and organizations involved in the program have developed a sound and viable working relationship, and it appears that the major objectives, primarily dispelling some of the concerns over weapons testing and radiation on the part of the public, are being effectively addressed. The program is certainly a dynamic operation, growing and changing to meet perceived needs and goals as more experience is gained through our work. The change in focus on our public outreach efforts will lead us to contacts with more students and schools, service clubs and special interest groups in the future, and will refine, and hopefully improve, our communication with the public. If that can be accomplished, plus perhaps influencing a few more students to stay in school and even grow up to be scientists, engineers and better citizens, we will be closer to having achieved our goals. It is important to note that the success of the program has occurred only because the people involved, from the Department of Energy, the Environmental Protection Agency, the Desert Research Institute, the University of Utah and the Station Managers and Alternates work well and hard together. Our extended family'' is doing a good job. 9 refs., 1 fig., 3 tabs.

  7. Using pan-Arctic, springtime, surface radiation observations to quantify atmospheric preconditioning processes that impact the sea ice melt season

    NASA Astrophysics Data System (ADS)

    Cox, Christopher; Uttal, Taneil; Starkweather, Sandy; Intrieri, Janet; Maturilli, Marion; Kustov, Vasily; Konopleva, Elena; Crepinsek, Sara; Long, Chuck

    2015-04-01

    Accurate, seasonal-scale forecasts of sea ice extent and distribution are critical for weather forecasting, transportation, the energy industry and local Arctic communities. Current forecasting methods capture an overall trend of decreasing sea ice on decadal scales, but do not reliably predict inter-annual variability. Recent work using satellite observations identified a relationship between spring-time, cloud modulated, shortwave radiation, and late season sea-ice extent; this relationship suggested an atmospheric preconditioning process that modulates the ice-albedo feedback and sets the stage for the melt season. Due to a general lack of emphasis on the role of the atmosphere on the evolution of the summer sea-ice, compounded by biases in cloud properties within models, this preconditioning process is poorly represented in current forecasting methods. Longwave and shortwave radiation data collected at the surface from stations surrounding the Arctic Basin as part of the Baseline Surface Radiation Network (BSRN) provide high-quality, continuous observations of the surface radiation budget. This includes downwelling fluxes and surface-cloud radiative interactions which cannot be directly acquired by satellites. These BSRN data are used to investigate the role of the atmosphere and clouds in seasonal scale variability of sea ice conditions, and the potential for improving predictability by incorporating these atmospheric observations into prediction strategies. We find that the downwelling fluxes measured at the land stations in spring are well correlated with sea ice conditions in September, especially in regions of the Arctic Ocean where late summer sea ice concentration has large inter-annual variability. Using observations of the total radiative flux (longwave + shortwave) at the surface, it is possible to make a seasonal sea-ice extent forecast that is within the range of uncertainty of forecasts currently incorporated into the Sea Ice Prediction Network

  8. Radiative-Convective Processes in Regulating Tropical Ocean-Atmosphere

    NASA Technical Reports Server (NTRS)

    Sui, C.-H.; Lau, K.-M.; Li, X.; Ho, C.-H.

    2000-01-01

    Relationship between sea surface temperature (SST) and cloud/water vapor reveals important information about radiative-climate feedbacks. Many previous studies have found that cloud amount and SST are positively correlated for SST between 28-29.5 C, for SST greater than 29.5 C, cloud amount actually decreases with increasing SST. The breakdown of SST-cloud correlation at 29.5 C was suggested to be related to the formation of localized hot spots with very high SST due to increased solar radiation in regions of strong subsidence forced by convection elsewhere. In this study, the breakdown is related to the radiative cooling in the subsidence regime over the cold pool surrounding the warm pool. We show model and observational evidence that radiative cooling over the cold pool limits the strength of SST-induced tropical circulation. As a result, occurrence of convection is also limited when SST contrast between the warm pool and cold pool is large.

  9. [Packaging in the process of radiation sterilization. II. Physicochemical studies].

    PubMed

    Pekala, W; Burczak, K; Czerniawski, E

    1986-01-01

    The penetrability of the ionizing radiation through the matter makes possible the sterilization of the medical devices in the packed form by radiation method. The effect of the radiation should not bring any destructive changes in the material used for the package. In this paper have been discussed the results of the investigations of the one--and multilayer packaging materials from the point of view their utility for the radiation sterilization purposes. The changes of the useful parameters of the investigated materials have been determined in the dependence on the absorbed dose immediately after irradiation and the period of the durable keeping after the sterilization. The results of the mechanical investigations in the correlation to the results of the microbiological effects of the sterilized materials enabled to draw practical conclusions concerned the usability of the particular packages. PMID:3797357

  10. QED Radiative Corrections in Processes of Exclusive Pion Electroproduction

    SciTech Connect

    Andrei Afanasev; I. Akushevich; Volker Burkert; K. Joo

    2002-03-01

    Formalism for radiative correction (RC) calculation in exclusive pion electroproduction on the proton is presented. A FORTRAN code EXCLURAD is developed for the RC procedure. The numerical analysis is done in the kinematics of current Jefferson Lab experiments.

  11. QED radiative corrections in processes of exclusive pion electroproduction

    NASA Astrophysics Data System (ADS)

    Afanasev, A.; Akushevich, I.; Burkert, V.; Joo, K.

    2002-10-01

    A formalism for radiative correction (RC) calculation in exclusive pion electroproduction on the proton is presented. A FORTRAN code EXCLURAD is developed for the RC procedure. The numerical analysis is done in the kinematics of current Jefferson Lab experiments.

  12. Nuclear Fragmentation Processes Relevant for Human Space Radiation Protection

    NASA Technical Reports Server (NTRS)

    Lin, Zi-Wei

    2007-01-01

    Space radiation from cosmic ray particles is one of the main challenges for human space explorations such-as a moon base or a trip to Mars. Models have been developed in order to predict the radiation exposure to astronauts and to evaluate the effectiveness of different shielding materials, and a key ingredient in these models is the physics of nuclear fragmentations. We have developed a semi-analytical method to determine which partial cross sections of nuclear fragmentations most affect the radiation dose behind shielding materials due to exposure to galactic cosmic rays. The cross sections thus determined will require more theoretical and/or experimental studies in order for us to better predict, reduce and mitigate the radiation exposure in human space explorations.

  13. Parameterization of Radiative Processes in Vertically Nonhomogeneous Multiple Scattering Atmospheres.

    NASA Astrophysics Data System (ADS)

    Fu, Qiang

    1991-02-01

    A radiation model has been developed to calculate the radiative fluxes and heating rates in plane parallel, vertically nonhomogeneous, multiple scattering atmospheres with an accuracy of better than 5%. This scheme is appropriate for use in climate and numerical prediction models to study the effect of cloud and radiation interactions. Parameterization of nongray gaseous absorption in vertically nonhomogeneous atmospheres has been developed based upon the correlated K-distribution method. The entire radiation spectrum is divided into 18 intervals: 6 in the solar and 12 in the infrared. By using a minimum number of quadrature points within each wavelength interval to represent the gaseous absorption and to treat overlap, we need to perform 121 spectral calculations for each vertical profile to obtain total radiative fluxes and heating rates. The treatment of gaseous absorption introduces errors less than 0.05 K/day in the heating rates below 30 km and and relative errors less than 0.5% in the fluxes. The single-scattering properties of water/ice clouds have been parameterized in terms of the effective size and liquid/ice water contents, based on Mie-scattering/ray -tracing computations with the best available size distributions. The parameterization gives an accuracy within about 1% in the solar and 5% in the infrared. By using the delta-four-stream approximation, a single algorithm has been developed for radiative transfer calculations. For vertically nonhomogeneous atmospheres, this code is numerically stable and computationally efficient. The accuracy of the algorithm is generally better than 5%, but it can produce more accurate results in the limit of no scattering. Compared with line-by-line results from clear -sky longwave calculations when all constituents were included, the errors in heating rates calculated by the new radiation model are less than 0.1 K/day in the troposphere and lower stratosphere. The errors in radiative fluxes are less than 1% both at

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

    SciTech Connect

    Thomas, M.L.; Hagemeyer, D.

    1998-02-01

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

  15. 42 CFR 137.401 - What role does Tribal consultation play in the IHS annual budget request process?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false What role does Tribal consultation play in the IHS annual budget request process? 137.401 Section 137.401 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES INDIAN HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES TRIBAL...

  16. 42 CFR 137.401 - What role does Tribal consultation play in the IHS annual budget request process?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false What role does Tribal consultation play in the IHS annual budget request process? 137.401 Section 137.401 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES INDIAN HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES TRIBAL...

  17. 42 CFR 137.401 - What role does Tribal consultation play in the IHS annual budget request process?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false What role does Tribal consultation play in the IHS annual budget request process? 137.401 Section 137.401 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES INDIAN HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES TRIBAL...

  18. 42 CFR 137.401 - What role does Tribal consultation play in the IHS annual budget request process?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false What role does Tribal consultation play in the IHS annual budget request process? 137.401 Section 137.401 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES INDIAN HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES TRIBAL...

  19. 42 CFR 137.401 - What role does Tribal consultation play in the IHS annual budget request process?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false What role does Tribal consultation play in the IHS annual budget request process? 137.401 Section 137.401 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES INDIAN HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES TRIBAL...

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

    SciTech Connect

    Ghisellini, G.

    2010-07-15

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

  1. Native shrub reestablishment in exotic annual grasslands: do ecosystem processes recover?

    PubMed

    Yelenik, S G; Levine, J M

    2010-04-01

    The impacts of exotic plant species on ecosystem processes are well established, motivating numerous efforts to facilitate native-species recovery. Nonetheless, how the return of native species influences ecosystem processes and how these changes feed back to influence the recovery process are poorly understood. We examined these questions in exotic annual grasslands on Santa Cruz Island, California, USA, where the removal of nonnative herbivores has led to the recovery of the native shrubs Artemisia californica and Eriogonum arborescens. To examine the influence of shrub colonization on nutrient cycling, and the mechanisms by which these changes arise, we measured available nitrogen and phosphorus, and quantified nitrogen mineralization and litterfall rates under shrubs and grasses in the field and in experimental monoculture plots. Both native shrubs altered nitrogen cycling as they colonized the grassland, but they did so in opposite directions. Eriogonum depressed nitrogen pools and mineralization rates via large inputs of nitrogen-poor litter. In contrast Artemisia increased nitrogen and phosphorus pools and nitrogen mineralization rates. Last, to determine if shrub effects on soils favor shrubs or grasses, we conducted a nitrogen and phosphorus fertilization experiment in the field. Only the exotic grass was significantly limited by nitrogen. Thus the depressed nitrogen availability associated with Eriogonum colonization is more harmful to exotic grasses than to the native shrub. By contrast, the elevated nitrogen associated with recovering Artemisia favors grasses over the shrub, possibly hindering recovery of the native. Mechanistic studies of the ecosystem ,impacts of native-plant recovery are useful for managers wishing to predict which native species return ecosystem function, and whether such changes feed back to influence native recovery. PMID:20437958

  2. Hydrothermal processing of Hanford tank waste. Organic destruction technology development task annual report -- FY 1993

    SciTech Connect

    Orth, R.J.; Schmidt, A.J.; Zacher, A.H.

    1993-09-01

    Low-temperature hydrothermal processing (HTP) is a thermal-chemical autogenous processing method that can be used to destroy organics and ferrocyanide in Hanford tank waste at temperatures from 250 C to 400 C. With HTP, organics react with oxidants, such as nitrite and nitrate, already present in the waste. Ferrocyanides and free cyanide will hydrolyze at similar temperatures and may also react with nitrates or other oxidants in the waste. No air or oxygen or additional chemicals need to be added to the autogenous HTP system. However, enhanced kinetics may be realized by air addition, and, if desired, chemical reductants can be added to the system to facilitate complete nitrate/nitrate destruction. Tank waste can be processed in a plug-flow, tubular reactor, or a continuous-stirred tank reactor system designed to accommodate the temperature, pressure, gas generation, and heat release associated with decomposition of the reactive species. The work described in this annual report was conducted in FY 1993 for the Organic Destruction Technology Development Task of Hanford`s Tank Waste Remediation System (TWRS). This task is part of an overall program to develop organic destruction technologies originally funded by TWRS to meet tank safety and waste form disposal criteria and condition the feed for further pretreatment. During FY 1993 the project completed seven experimental test plans, a 30-hr pilot-scale continuous run, over 200 hr of continuous bench-scale HTP testing, and 20 batch HTP tests; two contracts were established with commercial vendors, and a commercial laboratory reactor was procured and installed in a glovebox for HTP testing with actual Hanford tank waste.

  3. Radiation Exposures for DOE and DOE Contractor Employees - 1990. Twenty-third annual report

    SciTech Connect

    Smith, M. H.; Hui, T. E.; Millet, W. H.; Scholes, V. A.

    1993-11-01

    All U.S. Department of Energy and DOE contractors are required by DOE Order 5484.1, Chapter IV, to submit occupational radiation exposure records to a central depository. For 1990, data were required to be submitted for all employees who were required to be monitored in accordance with DOE Order 5480.11 and for all visitors who had a positive exposure. The data required included the total effective dose equivalent, external penetrating whole-body dose equivalent, internal dose equivalent, the shallow dose equivalent, neutron dose equivalent, and extremity dose equivalent. Data regarding the exposed individuals included the individual's age, sex, and occupation category. This report is a summary of data reported by DOE and DOE contractors for the calendar year 1990.

  4. In vivo mutagenicity and clastogenicity of ionizing radiation in nuclear medicine. Annual technical progress report, [1991

    SciTech Connect

    Kelsey, K.T.

    1991-12-31

    The overall goal of our research remains to investigate the mutagenic and clastogenic effects of exposure to low levels of ionizing radiation to human lymphocytes. Principally, we are studying hospital patients referred to a nuclear medicine department for diagnostic cardiac imaging and nuclear medicine technologies who administer radionuclides. Emphasis in the first year, as described in the first progress report, was on optimization of the hprt mutation assay, measurement of mutant frequencies in patients imaged with thallium-201, and measurement of mutant frequencies in controls. Emphasis in the second year has been on measurements of (1) chromosome aberrations in patients imaged with thallium-201, (2) mutant frequencies in patients imaged with technetium-99, (3) mutant frequencies in nuclear medicine technicians and physical therapists, (4) mutant frequencies in patients treated for Hodgkins disease with radiotherapy. The progress in these areas is described.

  5. Radiation Characteristics of a 0.11 Micrometer Modified Commercial CMOS Process

    NASA Technical Reports Server (NTRS)

    Poivey, Christian; Kim, Hak; Berg, Melanie D.; Forney, Jim; Seidleck, Christina; Vilchis, Miguel A.; Phan, Anthony; Irwin, Tim; LaBel, Kenneth A.; Saigusa, Rajan K.; Mirabedini, Mohammad R.; Finlinson, Rick; Suvkhanov, Agajan; Hornback, Verne; Sung, Jun; Tung, Jeffrey

    2006-01-01

    We present radiation data, Total Ionizing Dose and Single Event Effects, on the LSI Logic 0.11 micron commercial process and two modified versions of this process. Modified versions include a buried layer to guarantee Single Event Latchup immunity.

  6. 21 CFR 179.39 - Ultraviolet radiation for the processing and treatment of food.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ultraviolet radiation for the processing and treatment of food. 179.39 Section 179.39 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING OF FOOD Radiation...

  7. 21 CFR 179.39 - Ultraviolet radiation for the processing and treatment of food.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ultraviolet radiation for the processing and treatment of food. 179.39 Section 179.39 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING OF FOOD Radiation...

  8. Breaking of a single asperity: Rupture process and seismic radiation

    NASA Astrophysics Data System (ADS)

    Das, S.; Kostrov, B. V.

    1983-05-01

    The problem of spontaneous shear rupture of a single circular asperity on an infinite fault plane is studied. Initially, the fault plane is broken everywhere except at a circular asperity. An applied displacement at infinity results in a stress concentration along the bounding edge of the asperity. The frictional stress on the broken part of the fault plane is taken to be a constant. Once a point on the asperity breaks, the stress there drops to the same value as on the `main' fault surface. The rupture is started by relaxing the shear stress at a point on the asperity edge and is then allowed to propagate spontaneously, using a critical stress level fracture criterion. The rupture process is calculated numerically. It is found that for asperities of constant strength, the rupture first propagates around the edge of the asperity and then inward, a phenomenon best described by the well-known term of classic military maneuver: `the double encircling pincer movement.' In the appendix, the expressions for the far-field seismic radiation due to the rupture of such an asperity are derived. It is shown that the nth Cartesian component of the far-field displacement at (x, t) for P, SV, and SH waves, using the notation of Aki and Richards (1980), is given by un(x, t) = (Dni/4πρc2R)∫∫s0τi3{ξ, t - [(R - ξ · γ)/c]} dS(ξ). Thus the far-field pulses can be directly found from the stress drops on the fault plane. This formula is also true for `crack' or `dislocation' problems. The directivity function Dni for displacement for the asperity problem is found to be that for the double couple, modified by some factor. In particular, the fault plane is a nodal plane for SV waves. For the rupturing of asperities on a finite fault, these directivity functions are applicable only to the initial part of observed pulses at a receiver, provided the receiver is not located on the fault plane outside the broken part of the main crack edge, in which case it is inapplicable for all

  9. 1987 Annual Conference on Nuclear and Space Radiation Effects, Snowmass Village, CO, July 28-31, 1987, Proceedings

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Various papers on nuclear and space radiation effects are presented. The general topics addressed include: basic mechanisms of radiation effects, single-event phenomena, temperature and field effects, modeling and characterization of radiation effects, IC radiation effects and hardening, and EMP/SGEMP/IEMP phenomena. Also considered are: dosimetry/energy-dependent effects, sensors in and for radiation environments, spacecraft charging and space radiation effects, radiation effects and devices, radiation effects on isolation technologies, and hardness assurance and testing techniques.

  10. Parameterization of radiative processes in vertically nonhomogeneous multiple scattering atmospheres

    NASA Astrophysics Data System (ADS)

    Fu, Qiang

    1991-05-01

    A radiation model has been developed to calculate the radiative fluxes and heating rates in plane parallel, vertically nonhomogeneous, multiple scattering atmospheres with an accuracy of better than 5 percent. This scheme is appropriate for use in climate and numerical prediction models to study the effect of cloud and radiation interactions. Parameterization of nongray gaseous absorption in vertically nonhomogeneous atmospheres has been developed based upon the correlated K-distribution method. The entire radiation spectrum is divided into 18 intervals: 6 in the solar and 12 in the infrared. By using a minimum number of quadrature points within each wavelength interval to represent the gaseous absorption and to treat overlap, we need to perform 121 spectral calculations for each vertical profile to obtain total radiative fluxes and heating rates. The treatment of gaseous absorption introduces errors less than 0.05 K/day in the heating rates below 30 km and relative errors less than 0.5 percent in the fluxes. The single-scattering properties of water/ice clouds have been parameterized in terms of the effective size and liquid/ice water contents, based on Mie-scattering/ray-tracing computations with the best available size distributions. The parameterization gives an accuracy within about 1 percent in the solar and 5 percent in the infrared. By using the delta-four-stream approximation, a single algorithm has been developed for radiative transfer calculations. For vertically nonhomogeneous atmospheres, this code is numerically stable and computationally efficient. The accuracy of the algorithm is generally better than 5 percent, but it can produce more accurate results in the limit of no scattering. Compared with line-by-line results from clear-sky longwave calculations when all constituents were included, the errors in heating rates calculated by the new radiation model are less than 0.1 K/day in the troposphere and lower stratosphere. The errors in radiative

  11. ESC FY2002 Annual Report: Synchrotron-Radiation-Based Photoelectron Spectroscopy at the Advanced Light Source

    SciTech Connect

    Tobin, J G; Chung, B W; Schulze, R K; Shuh, D K

    2002-10-04

    Despite recent intensive experimental effort, the electronic structure of Pu, particularly {delta}-Pu, remains ill defined. An evaluation of our previous synchrotron-radiation-based investigation of {alpha}-Pu and {delta}-Pu has lead to a new paradigm for the interpretation of photoemission spectra of U, Np, {alpha}-Pu, {delta}-Pu and Am. This approach is founded upon a model in which spin and spin-orbit splittings are included in the picture of the 5f states and upon the observation of chiral/spin-dependent effects in non-magnetic systems. By extending a quantitative model developed for the interpretation of core level spectroscopy in magnetic systems, it is possible to predict the contributions of the individual component states within the 5-f manifold. This has lead to a remarkable agreement between the results of the model and the previously collected spectra of U, Np, Pu and Am, particularly {delta}-Pu, and to a prediction of what we might expect to see in future spin-resolving experiments.

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

    SciTech Connect

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

    2007-01-01

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

  13. Human genetic marker for resistance to radiations and chemicals. 1997 annual progress report

    SciTech Connect

    Lieberman, H.B.

    1997-01-01

    'The specific aims listed in the original application will essentially be pursued as indicated. The major goal of the grant is to characterize a human homologue of the fission yeast Schizosaccharomyces pombe rad9 checkpoint control, radioresistance and chemoresistance gene, which is called HRAD9. The purpose is to gain information about the gene, including its structure and function, such that it can potentially be developed as a human genetic marker indicative of hypersensitivity to the deleterious effects associated with exposure to radiations or certain chemicals. The specific aims are divided into two major sections. The first section includes experiments designed to characterize the HRAD9 gene at the molecular level. Specifically, the genomic version of the gene will be isolated and its DNA sequence determined, in vitro mutagenesis will be used to assess structure/function relationships, and expression in cells and tissues will be examined. The second major set of aims focuses on determining the role of HRAD9 in radio/chemoresponsiveness and cancer. For this aim, human HRAD9 mutants will be constructed and characterized. In addition, the status of HRAD9 in cancer cells and tissues will be assessed.'

  14. Community Radiation Monitoring Program; Annual report, October 1, 1990--September 30, 1991

    SciTech Connect

    Cooper, E.N.; McArthur, R.D.

    1992-06-01

    The Community Radiation Monitoring Program is a cooperative effort between the US Department of Energy (DOE), the US Environmental Protection Agency (EPA), the Desert Research Institute (DRI), a division of the University and Community College System of Nevada, and the Nuclear Engineering Laboratory of the University of Utah (U of U). This eleventh year of the program began in the summer of 1991 and the work continues as an integral part of the DOE-sponsored long-term offsite radiological monitoring effort that has been conducted by EPA and its predecessors since the inception of nuclear testing at the Nevada Test Site (NTS). The primary objectives of this program are still to increase the understanding by the people who live in the area surrounding the NTS of the activities for which the DOE is responsible, to enhance the performance of radiological sampling and monitoring, and to inform all concerned of the results of those efforts. One of the primary methods used to improve the communication link with the potentially impacted area has been the hiring and training of local citizens as Managers and program representatives in 19 communities adjacent to and downwind from the NTS. These Managers, active science teachers wherever possible, have succeeded, through their training, experience, community standing, and effort, in becoming a very visible, able and valuable asset in this link.

  15. Microscopic Processes On Radiation from Accelerated Particles in Relativistic Jets

    NASA Technical Reports Server (NTRS)

    Nishikawa, K.-I.; Hardee, P. E.; Mizuno, Y.; Medvedev, M.; Zhang, B.; Sol, H.; Niemiec, J.; Pohl, M.; Nordlund, A.; Fredriksen, J.; Lyubarsky, Y.; Hartmann, D. H.; Fishman, G. J.

    2009-01-01

    Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks, e.g., gamma-ray bursts (GRBs), active galactic nuclei (AGNs), and Galactic microquasar systems usually have power-law emission spectra. Recent PIC simulations of relativistic electron-ion (electro-positron) jets injected into a stationary medium show that particle acceleration occurs within the downstream jet. In the collisionless relativistic shock particle acceleration is due to plasma waves and their associated instabilities (e.g., the Buneman instability, other two-streaming instability, and the Weibel (filamentation) instability) created in the shocks are responsible for particle (electron, positron, and ion) acceleration. The simulation results show that the Weibel instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields. These magnetic fields contribute to the electron's transverse deflection behind the jet head. The jitter'' radiation from deflected electrons has different properties than synchrotron radiation which is calculated in a uniform magnetic field. This jitter radiation may be important to understanding the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets, and supernova remnants.

  16. Community radiation monitoring program. Annual report, October 1, 1992--September 30, 1993

    SciTech Connect

    Cooper, E.N.

    1994-08-01

    The Community Radiation Monitoring Program (CRMP) is a cooperative effort between the US Department of Energy (DOE), the US Environmental Protection Agency (EPA), the Desert Research Institute (DRI), a division of the University and Community College System of Nevada, and the Nuclear Engineering Laboratory of the University of Utah (UUNEL). The thirteenth year of this program began in the fall of 1992, and the work continues as an integral part of the DOE--sponsored long-term offsite radiological monitoring effort that has been conducted by EPA and its predecessors since the inception of nuclear testing at the Nevada Test Site (NTS). The CRMP began by enhancing and centralizing environmental monitoring and sampling equipment at 15 communities in the then-existing EPA monitoring network around the NTS, and has since expanded to 19 locations in Nevada, Utah, and California. The primary objectives of this program are still to increase the understanding by the people who live in the area surrounding the NTS of the activities for which DOE is responsible, to enhance the performance of radiological sampling and monitoring, and to inform all concerned of the results of these efforts. One of the primary methods used to improve the communication link with the people in the potentially impacted area has been the hiring and training of local citizens as Station Managers and program representatives in those selected communities in the offsite area. These mangers, active science teachers wherever possible, have succeeded through their training, experience, community standing, and effort in becoming a very visible, able, and valuable asset in this link.

  17. Community Radiation Monitoring Program. Annual report, October 1, 1991--September 30, 1992

    SciTech Connect

    Cooper, E.N.

    1993-05-01

    The Community Radiation Monitoring Program (CRMP) is a cooperative effort between the US Department of Energy (DOE); the US Environmental Protection Agency (EPA); the Desert Research Institute (DRI), a division of the University and Community College System of Nevada and the Nuclear Engineering Laboratory of the University of Utah (UNEL). The twelfth year of the program began in the fall of 1991, and the work continues as an integral part of the DOE-sponsored long-term offsite radiological monitoring effort that has been conducted by EPA and its predecessors since the inception of nuclear testing at the Nevada Test Site (NTS). The program began as an outgrowth of activities that occurred during the Three Mile Island incident in 1979. The local interest and public participation that took place there were thought to be transferrable to the situation at the NTS, so, with adaptations, that methodology was implemented for this program. The CRMP began by enhancing and centralizing environmental monitoring and sampling equipment at 15 communities in the existing EPA monitoring network, and has since expanded to 19 locations in Nevada, Utah and California. The primary objectives of this program are still to increase the understanding by the people who live in the area surrounding the NTS of the activities for which DOE is responsible, to enhance the performance of radiological sampling and monitoring, and to inform all concerned of the results of these efforts. One of the primary methods used to improve the communication link with people in the potentially impacted area has been the hiring and training of local citizens as station managers and program representatives in those selected communities in the offsite area. These managers, active science teachers wherever possible, have succeeded, through their training, experience, community standing, and effort, in becoming a very visible, able and valuable asset in this link.

  18. Improving degradation of paracetamol by integrating gamma radiation and Fenton processes.

    PubMed

    Cruz-González, Germán; Rivas-Ortiz, Iram B; González-Labrada, Katia; Rapado-Paneque, Manuel; Chávez-Ardanza, Armando; Nuevas-Paz, Lauro; Jáuregui-Haza, Ulises J

    2016-10-14

    Degradation of paracetamol (N-(4-hydroxiphenyl)acetamide) in aqueous solution by gamma radiation, gamma radiation/H2O2 and gamma radiation/Fenton processes was studied. Parameters affecting the radiolysis of paracetamol such as radiation dose, initial concentration of pollutant, pH and initial oxidant concentration were investigated. Gamma radiation was performed using a (60)Co source irradiator. Paracetamol degradation and mineralization increased with increasing absorbed radiation dose, but decreased with increasing initial concentration of the drug in aqueous solution. The addition of H2O2 resulted in an increased effect on irradiation-driven paracetamol degradation in comparison with the performance of the irradiation-driven process alone: paracetamol removal increased from 48.9% in the absence of H2O2 to 95.2% for H2O2 concentration of 41.7 mmol/L. However, the best results were obtained with gamma radiation/Fenton process with 100% of the drug removal at 5 kGy, for optimal H2O2 and Fe(2+) concentrations at 13.9 and 2.3 mmol/L, respectively, with a high mineralization of 63.7%. These results suggest gamma radiation/H2O2 and gamma radiation/Fenton processes as promising methods for paracetamol degradation in polluted wastewaters. PMID:27389621

  19. Expected and unexpected achievements and trends in radiation processing of polymers

    NASA Astrophysics Data System (ADS)

    Czvikovszky, T.

    2003-06-01

    The last four decades produced exponential development in the polymer processing. Radiation processing—initiated also about 40 years ago—yielded a similar pathway of development in the beginning, mostly in the radiation crosslinking of polymers and in the radiation sterilization of polymer products. There are some unexpected results in the developments of the radiation chemistry of polymers utilized well in the polymer processing today. The most dynamical developments of the microelectronics in our days are based on the efficient utilization of radiation-crosslinkable negative photoresist polymers and the radiation degradable positive photoresist polymers. Rapid prototyping and rapid tooling are indispensable methods in the continuously renewing manufacturing technologies of metal and plastic parts for almost all the industrial branches. Polymer composite manufacturing is also profited in many ways from the experiences of radiation technology. Compatibilization through radiation-reactive monomers and oligomers is attacking two great fields of the future polymer processing. Recycling of commingled polymer wastes, and manufacturing new type of alloys of different synthetic as well as natural polymers are requiring well-engineered interface, which can be achieved by radiation processing in a technically feasible and economically viable way.

  20. Microwave-assisted chemical process for treatment of hazardous waste: Annual report

    SciTech Connect

    Varma, R.; Nandi, S.P.; Cleaveland, D.C.

    1987-10-01

    Microwave energy provides rapid in situ uniform heating and can be used to initiate chemical processes at moderate temperatures. We investigate the technical feasibility of microwave-assisted chemical processes for detoxification of liquid hazardous waste. Trichloroethylene, a major constituent of waste streams, was selected for this detoxification study. Experiments were performed to investigate the oxidative degradation of trichloroethylene over active carbons (with and without catalysts) in air streams with microwave in situ heating, and to examine the feasibility of regenerating the used carbons. This study established that trichloroethylene in a vapor stream can be adsorbed at room temperature on active carbon beds that are loaded with Cu and Cr catalysts. When the bed is heated by a microwave radiation to moderate temperatures (<400/sup 0/C) while a moist air stream is passed through it, the trichloroethylene is readily converted into less-noxious products such as HCl, CO, CO/sub 2/ and C/sub 2/H/sub 2/Cl/sub 2/. Conversion higher than 80% was observed. Furthermore, the used carbon bed can be conveniently regenerated by microwave heating while a moist-N/sub 2/ or moist-air stream is passed through the bed. 4 refs., 5 figs., 10 tabs.

  1. Effectiveness of radiation processing in elimination of Aeromonas from food

    NASA Astrophysics Data System (ADS)

    Nagar, Vandan; Bandekar, Jayant R.

    2011-08-01

    Genus Aeromonas has emerged as an important human pathogen because it causes a variety of diseases including gastroenteritis and extra-intestinal infections. Contaminated water, sprouts, vegetables, seafood and food of animal origin have been considered to be the important sources of Aeromonas infection. In the present study, radiation sensitivity of indigenous strains of Aeromonas spp. from different food samples was evaluated. The decimal reduction dose (D10) values of different Aeromonas isolates in saline at 0-4 °C were in the range of 0.031-0.046 kGy. The mixed sprouts, chicken and fish samples were inoculated with a cocktail of five most resistant isolates (A. salmonicida Y567, A. caviae A85, A. jandaei A514A, A. hydrophila CECT 839T and A. veronii Y47) and exposed to γ radiation to study the effectiveness of radiation treatment in elimination of Aeromonas. D10 values of Aeromonas cocktail in mixed sprouts, chicken and fish samples were found to be 0.081±0.001, 0.089±0.003 and 0.091±0.003 kGy, respectively. Radiation treatment with a 1.5 kGy dose resulted in complete elimination of 105 CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples. No recovery of Aeromonas was observed in the 1.5 kGy treated samples stored at 4 °C up to 12 (mixed sprouts) and 7 days (chicken and fish samples), even after enrichment and selective plating. This study demonstrates that a 1.5 kGy dose of irradiation treatment could result in complete elimination of 105 CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples.

  2. Quantum information processing with long-wavelength radiation

    NASA Astrophysics Data System (ADS)

    Murgia, David; Weidt, Sebastian; Randall, Joseph; Lekitsch, Bjoern; Webster, Simon; Navickas, Tomas; Grounds, Anton; Rodriguez, Andrea; Webb, Anna; Standing, Eamon; Pearce, Stuart; Sari, Ibrahim; Kiang, Kian; Rattanasonti, Hwanjit; Kraft, Michael; Hensinger, Winfried

    To this point, the entanglement of ions has predominantly been performed using lasers. Using long wavelength radiation with static magnetic field gradients provides an architecture to simplify construction of a large scale quantum computer. The use of microwave-dressed states protects against decoherence from fluctuating magnetic fields, with radio-frequency fields used for qubit manipulation. I will report the realisation of spin-motion entanglement using long-wavelength radiation, and a new method to efficiently prepare dressed-state qubits and qutrits, reducing experimental complexity of gate operations. I will also report demonstration of ground state cooling using long wavelength radiation, which may increase two-qubit entanglement fidelity. I will then report demonstration of a high-fidelity long-wavelength two-ion quantum gate using dressed states. Combining these results with microfabricated ion traps allows for scaling towards a large scale ion trap quantum computer, and provides a platform for quantum simulations of fundamental physics. I will report progress towards the operation of microchip ion traps with extremely high magnetic field gradients for multi-ion quantum gates.

  3. Latest Development of Infrared Radiation Heating for Food Processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infrared (IR) heating could be an alternative technology for thermal and dehydration processing of food and agricultural products with many advantages, including high process and energy efficiencies, high product quality, improved food safety and reduced environmental pollution. This paper reviews ...

  4. Laminar Soot Processes Experiment Shedding Light on Flame Radiation

    NASA Technical Reports Server (NTRS)

    Urban, David L.

    1998-01-01

    The Laminar Soot Processes (LSP) experiment investigated soot processes in nonturbulent, round gas jet diffusion flames in still air. The soot processes within these flames are relevant to practical combustion in aircraft propulsion systems, diesel engines, and furnaces. However, for the LSP experiment, the flames were slowed and spread out to allow measurements that are not tractable for practical, Earth-bound flames.

  5. A new mechanism for radiation damage processes in alkali halides

    NASA Astrophysics Data System (ADS)

    Dubinko, V. I.; Turkin, A. A.; Vainshtein, D. I.; den Hartog, H. W.

    1999-12-01

    We present a theory of radiation damage formation in alkali halides based on a new mechanism of dislocation climb, which involves the production of VF centers (self-trapped hole neighboring a cation vacancy) as a result of the absorption of H centers of dislocation lines. We consider the evolution of all experimentally observed extended defects: metal colloids, gas bubbles, and vacancy voids. Voids are shown to arise and grow large due to the reaction between F and VF centers at the surface of halogen bubbles. Voids can ignite a back reaction between the radiolytic products resulting in decomposition of the irradiated material.

  6. Twelfth Annual Warren K. Sinclair Keynote Address--the Influence of the NCRP on Radiation Protection in the United States: Guidance and Regulation.

    PubMed

    Kase, Kenneth R

    2016-02-01

    The Warren K. Sinclair Keynote Address for the 2015 Annual Meeting of the National Council on Radiation Protection and Measurements (NCRP) describes the Council's influence in the development of radiation protection guidance in the United States since its founding in 1929 as the U.S. Advisory Committee on X-Ray and Radium Protection. The National Bureau of Standards (NBS) was the coordinating agency for the Advisory Committee, and its reports were published as NBS handbooks. In 1946, the Advisory Committee was renamed the National Committee on Radiation Protection and remained so until NCRP was chartered by the U.S. Congress in 1964. In 1931, the U.S. Advisory Committee on X-Ray and Radium Protection proposed the first formal standard for protecting people from radiation sources as NBS Handbook 15 and issued the first handbook on radium protection, NBS Handbook 18. Revised recommendations for external exposure were issued in 1936 and for radium protection in 1938 and remained in force until 1948. Throughout its 86 y history, the Council and its predecessors have functioned as effective advisors to the nation on radiation protection issues and have provided the fundamental guidance and recommendations necessary for the regulatory basis of the control of radiation exposure, radiation-producing devices, and radioactive materials in the United States. PMID:26717165

  7. 2013 Annual Site Inspection and Monitoring Report for Uranium Mill Tailings Radiation Control Act Title I Disposal Sites

    SciTech Connect

    None, None

    2014-03-01

    This report, in fulfillment of a license requirement, presents the results of long-term surveillance and maintenance activities conducted by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) in 2013 at 19 uranium mill tailings disposal sites established under Title I of the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978.1 These activities verified that the UMTRCA Title I disposal sites remain in compliance with license requirements. DOE operates 18 UMTRCA Title I sites under a general license granted by the U.S. Nuclear Regulatory Commission (NRC) in accordance with Title 10 Code of Federal Regulations Part 40.27 (10 CFR 40.27). As required under the general license, a long-term surveillance plan (LTSP) for each site was prepared by DOE and accepted by NRC. The Grand Junction, Colorado, Disposal Site, one of the 19 Title I sites, will not be included under the general license until the open, operating portion of the cell is closed. The open portion will be closed either when it is filled or in 2023. This site is inspected in accordance with an interim LTSP. Long-term surveillance and maintenance services for these disposal sites include inspecting and maintaining the sites; monitoring environmental media and institutional controls; conducting any necessary corrective actions; and performing administrative, records, stakeholder relations, and other regulatory stewardship functions. Annual site inspections and monitoring are conducted in accordance with site-specific LTSPs and procedures established by DOE to comply with license requirements. Each site inspection is performed to verify the integrity of visible features at the site; to identify changes or new conditions that may affect the long-term performance of the site; and to determine the need, if any, for maintenance, follow-up or contingency inspections, or corrective action in accordance with the LTSP. LTSPs and site compliance reports are available on the Internet at http://www.lm.doe.gov/.

  8. 2013 Annual Site Inspection and Monitoring Report for Uranium Mill Tailings Radiation Control Act Title II Disposal Sites

    SciTech Connect

    2013-11-01

    This report, in fulfillment of a license requirement, presents the results of long-term surveillance and maintenance activities conducted by the U.S. Department of Energy (DOE) Office of Legacy Management in 2013 at six uranium mill tailings disposal sites reclaimed under Title II of the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978. These activities verified that the UMTRCA Title II disposal sites remain in compliance with license requirements. DOE manages six UMTRCA Title II disposal sites under a general license granted by the U.S. Nuclear Regulatory Commission (NRC) established at Title 10 Code of Federal Regulations Part 40.28. Reclamation and site transition activities continue at other sites, and DOE ultimately expects to manage approximately 27 Title II disposal sites. Long-term surveillance and maintenance activities and services for these disposal sites include inspecting and maintaining the sites; monitoring environmental media and institutional controls; conducting any necessary corrective action; and performing administrative, records, stakeholder services, and other regulatory functions. Annual site inspections and monitoring are conducted in accordance with site-specific long-term surveillance plans (LTSPs) and procedures established by DOE to comply with license requirements. Each site inspection is performed to verify the integrity of visible features at the site; to identify changes or new conditions that may affect the long-term performance of the site; and to determine the need, if any, for maintenance, follow-up inspections, or corrective action. LTSPs and site compliance reports are available online at http://www.lm.doe.gov

  9. Determination of volatiles produced during radiation processing in Laurus cinnamomum

    NASA Astrophysics Data System (ADS)

    Salum, D. C.; Araújo, M. M.; Fanaro, G. B.; Purgatto, E.; Villavicencio, A. L. C. H.

    2009-07-01

    In order to protect food from pathogenic microorganisms as well as increase its shelf-life, while keeping sensorial properties (e.g., odor and taste), which are important properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. Possible changes in the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties, in order to allow better application of the irradiation technology. The aim of the present study was to analyze volatile formation on cinnamon ( Laurus cinnamomum) samples after gamma irradiation. These samples were irradiated into plastic packages using a 60Co facility. Radiation doses applied were 0, 5, 10, 15, 20 and 25 kGy. For the analysis of the samples, solid-phase microextraction (SPME) was applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation showed the highest decrease in volatile compounds. For L. cinnamomum, the irradiation decreased volatile compounds by nearly 56% and 89.5%, respectively, comparing to volatile from a sample which had not been previously irradiated.

  10. Uniform bulk Material Processing using Multimode Microwave Radiation

    SciTech Connect

    Varma, Ravi; Vaughan, Worth E.

    1999-06-18

    An apparatus for generating uniform heating in material contained in a cylindrical vessel is described. TE{sub 10}-mode microwave radiation is coupled into a cylindrical microwave transition such that microwave radiation having TE{sub 11}-, TE{sub 01}- and TM{sub 01}-cylindrical modes is excited therein. By adjusting the intensities of these modes, substantially uniform heating of materials contained in a cylindrical drum which is coupled to the microwave transition through a rotatable choke can be achieved. The use of a poor microwave absorbing insulating cylindrical insert, such as aluminum oxide, for separating the material in the container from the container walls and for providing a volume through which air is circulated is expected to maintain the container walls at room temperature. The use of layer of highly microwave absorbing material, such as SiC, inside of the insulating insert and facing the material to be heated is calculated to improve the heating pattern of the present apparatus.

  11. Uniform bulk material processing using multimode microwave radiation

    DOEpatents

    Varma, Ravi; Vaughn, Worth E.

    2000-01-01

    An apparatus for generating uniform heating in material contained in a cylindrical vessel is described. TE.sub.10 -mode microwave radiation is coupled into a cylindrical microwave transition such that microwave radiation having TE.sub.11 -, TE.sub.01 - and TM.sub.01 -cylindrical modes is excited therein. By adjusting the intensities of these modes, substantially uniform heating of materials contained in a cylindrical drum which is coupled to the microwave transition through a rotatable choke can be achieved. The use of a poor microwave absorbing insulating cylindrical insert, such as aluminum oxide, for separating the material in the container from the container walls and for providing a volume through which air is circulated is expected to maintain the container walls at room temperature. The use of layer of highly microwave absorbing material, such as SiC, inside of the insulating insert and facing the material to be heated is calculated to improve the heating pattern of the present apparatus.

  12. The EM SSAB Annual Work Plan Process: Focusing Board Efforts and Resources - 13667

    SciTech Connect

    Young, Ralph

    2013-07-01

    One of the most daunting tasks for any new member of a local board of the Environmental Management Site Specific Advisory Board (EM SSAB) is to try to understand the scope of the clean-up activities going on at the site. In most cases, there are at least two or three major cleanup activities in progress as well as monitoring of past projects. When planning for future projects is added to the mix, the list of projects can be long. With the clean-up activities involving all major environmental media - air, water, soils, and groundwater, new EM SSAB members can find themselves totally overwhelmed and ineffective. Helping new members get over this initial hurdle is a major objective of EM and all local boards of the EM SSAB. Even as members start to understand the size and scope of the projects at a site, they can still be frustrated at the length of time it takes to see results and get projects completed. Many project and clean-up timelines for most of the sites go beyond 10 years, so it's not unusual for an EM SSAB member to see the completion of only 1 or 2 projects over the course of their 6-year term on the board. This paper explores the annual work planning process of the EM SSAB local boards, one tool that can be used to educate EM SSAB members into seeing the broader picture for the site. EM SSAB local work plans divide the site into projects focused on a specific environmental issue or media such as groundwater and/or waste disposal options. Projects are further broken down into smaller segments by highlighting major milestones. Using these metrics, local boards of the EM SSAB can start to quantify the effectiveness of the project in achieving the ultimate goal of site clean-up. These metrics can also trigger board advice and recommendations for EM. At the beginning of each fiscal year, the EM SSAB work plan provides a road map with quantifiable checkpoints for activities throughout the year. When the work plans are integrated with site-specific, enforceable

  13. Modeling photosynthesis of discontinuous plant canopies by linking Geometric Optical Radiative Transfer model with biochemical processes

    NASA Astrophysics Data System (ADS)

    Xin, Q.; Gong, P.; Li, W.

    2015-02-01

    Modeling vegetation photosynthesis is essential for understanding carbon exchanges between terrestrial ecosystems and the atmosphere. The radiative transfer process within plant canopies is one of the key drivers that regulate canopy photosynthesis. Most vegetation cover consists of discrete plant crowns, of which the physical observation departs from the underlying assumption of a homogenous and uniform medium in classic radiative transfer theory. Here we advance the Geometric Optical Radiative Transfer (GORT) model to simulate photosynthesis activities for discontinuous plant canopies. We separate radiation absorption into two components that are absorbed by sunlit and shaded leaves, and derive analytical solutions by integrating over the canopy layer. To model leaf-level and canopy-level photosynthesis, leaf light absorption is then linked to the biochemical process of gas diffusion through leaf stomata. The canopy gap probability derived from GORT differs from classic radiative transfer theory, especially when the leaf area index is high, due to leaf clumping effects. Tree characteristics such as tree density, crown shape, and canopy length affect leaf clumping and regulate radiation interception. Modeled gross primary production (GPP) for two deciduous forest stands could explain more than 80% of the variance of flux tower measurements at both near hourly and daily time scales. We also demonstrate that the ambient CO2 concentration influences daytime vegetation photosynthesis, which needs to be considered in state-of-the-art biogeochemical models. The proposed model is complementary to classic radiative transfer theory and shows promise in modeling the radiative transfer process and photosynthetic activities over discontinuous forest canopies.

  14. 16 CFR 610.3 - Streamlined process for requesting annual file disclosures from nationwide specialty consumer...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Practices FEDERAL TRADE COMMISSION THE FAIR CREDIT REPORTING ACT FREE ANNUAL FILE DISCLOSURES § 610.3... under the Fair Credit Reporting Act, section 610(a)(1), 15 U.S.C. 1681h(a)(1), and other applicable laws... specialty consumer reporting agency and with the Federal Trade Commission; and (C) In the event that...

  15. 16 CFR 610.3 - Streamlined process for requesting annual file disclosures from nationwide specialty consumer...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... file disclosures from nationwide specialty consumer reporting agencies. 610.3 Section 610.3 Commercial Practices FEDERAL TRADE COMMISSION THE FAIR CREDIT REPORTING ACT FREE ANNUAL FILE DISCLOSURES § 610.3..., providing access to a “help” or “frequently asked questions” screen, which includes more...

  16. 16 CFR 610.3 - Streamlined process for requesting annual file disclosures from nationwide specialty consumer...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... file disclosures from nationwide specialty consumer reporting agencies. 610.3 Section 610.3 Commercial Practices FEDERAL TRADE COMMISSION THE FAIR CREDIT REPORTING ACT FREE ANNUAL FILE DISCLOSURES § 610.3..., providing access to a “help” or “frequently asked questions” screen, which includes more...

  17. Basic physical and chemical processes in space radiation effects on polymers

    NASA Technical Reports Server (NTRS)

    Kamaratos, E.; Wilson, J. W.; Chang, C. K.; Xu, Y. J.

    1982-01-01

    The effects of space ionizing radiation on polymers is investigated in terms of operative physical and chemical processes. A useful model of charged particle impact with a polymer was designed. Principle paths of molecular relaxation were identified and energy handling processes were considered. The focus of the study was on energy absorption and the immediately following events. Further study of the radiation degradation of polymers is suggested.

  18. 1988 IEEE Annual Conference on Nuclear and Space Radiation Effects, 25th, Portland, OR, July 12-15, 1988, Proceedings

    NASA Technical Reports Server (NTRS)

    Coakley, Peter G. (Editor)

    1988-01-01

    The effects of nuclear and space radiation on the performance of electronic devices are discussed in reviews and reports of recent investigations. Topics addressed include the basic mechanisms of radiation effects, dosimetry and energy-dependent effects, sensors in and for radiation environments, EMP/SGEMP/IEMP phenomena, radiation effects on isolation technologies, and spacecraft charging and space radiation effects. Consideration is given to device radiation effects and hardening, hardness assurance and testing techniques, IC radiation effects and hardening, and single-event phenomena.

  19. Annual Conference on Nuclear and Space Radiation Effects, 21st, Colorado Springs, CO, July 23-25, 1984, Proceedings

    NASA Technical Reports Server (NTRS)

    Winokur, P. S. (Editor)

    1984-01-01

    Radiation effects on electronic systems and devices (particularly spacecraft systems) are examined with attention given to such topics as radiation transport, energy deposition, and charge collection; single-event phenomena; basic mechanisms of radiation effects in structures and materials; and EMP phenomena. Also considered are radiation effects in integrated circuits, spacecraft charging and space radiation effects, hardness assurance for devices and systems, and SGEMP/IEMP phenomena.

  20. Low Dose Radiation-Induced Genome and Epigenome Instability Symposium and Epigenetic Mechanisms, DNA Repair, and Chromatin Symposium at the EMS 2008 Annual Meeting - October 2008

    SciTech Connect

    Morgan, William F; Kovalchuk, Olga; Dolinoy, Dana C; Dubrova, Yuri E; Coleman, Matthew A; Schär, Primo; Pogribny, Igor; Hendzel, Michael

    2010-02-19

    The Low Dose Radiation Symposium thoughtfully addressed ionizing radiation non-mutational but transmissable alterations in surviving cells. Deregulation of epigenetic processes has been strongly implicated in carcinogenesis, and there is increasing realization that a significant fraction of non-targeted and adaptive mechanisms in response to ionizing radiation are likely to be epigenetic in nature. Much remains to be learned about how chromatin and epigenetic regulators affect responses to low doses of radiation, and how low dose radiation impacts other epigenetic processes. The Epigenetic Mechanisms Symposium focused on on epigenetic mechanisms and their interplay with DNA repair and chromatin changes. Addressing the fact that the most well understood mediators of epigenetic regulation are histone modifications and DNA methylation. Low levels of radiation can lead to changes in the methylation status of certain gene promoters and the expression of DNA methyltransferases, However, epigenetic regulation can also involve changes in higher order chromosome structure.

  1. Process for making solid-state radiation-emitting composition

    DOEpatents

    Ashley, Carol S.; Brinker, C. Jeffrey; Reed, Scott; Walko, Robert J.

    1993-01-01

    The invention provides a process for loading an aerogel substrate with tritium and the resultant compositions. According to the process, an aerogel substrate is hydrolyzed so that surface OH groups are formed. The hydrolyzed aerogel is then subjected to tritium exchange employing, for example, a tritium-containing gas, whereby tritium atoms replace H atoms of surface OH groups. OH and/or CH groups of residual alcohol present in the aerogel may also undergo tritium exchange.

  2. Process for making solid-state radiation-emitting composition

    DOEpatents

    Ashley, C.S.; Brinker, C.J.; Reed, S.; Walko, R.J.

    1993-08-31

    The invention provides a process for loading an aerogel substrate with tritium and the resultant compositions. According to the process, an aerogel substrate is hydrolyzed so that surface OH groups are formed. The hydrolyzed aerogel is then subjected to tritium exchange employing, for example, a tritium-containing gas, whereby tritium atoms replace H atoms of surface OH groups. OH and/or CH groups of residual alcohol present in the aerogel may also undergo tritium exchange.

  3. Theory of molecular rate processes in the presence of intense laser radiation

    NASA Technical Reports Server (NTRS)

    George, T. F.; Zimmerman, I. H.; Devries, P. L.; Yuan, J.-M.; Lam, K.-S.; Bellum, J. C.; Lee, H.-W.; Slutsky, M. S.; Lin, J.-T.

    1979-01-01

    The present paper deals with the influence of intense laser radiation on gas-phase molecular rate processes. Representations of the radiation field, the particle system, and the interaction involving these two entities are discussed from a general rather than abstract point of view. The theoretical methods applied are outlined, and the formalism employed is illustrated by application to a variety of specific processes. Quantum mechanical and semiclassical treatments of representative atom-atom and atom-diatom collision processes in the presence of a field are examined, and examples of bound-continuum processes and heterogeneous catalysis are discussed within the framework of both quantum-mechanical and semiclassical theories.

  4. Inter-annual variability of exchange processes at the outer Black Sea shelf

    NASA Astrophysics Data System (ADS)

    Shapiro, Georgy; Wobus, Fred; Yuan, Dongliang; Wang, Zheng

    2014-05-01

    The advection of cold water below the surface mixed layer has a significant role in shaping the properties of the Cold Intermediate Layer (CIL) in the Black Sea, and thus the horizontal redistribution of nutrients. The minimal temperature of the CIL in the southwest deep region of the sea in summer was shown to be lower than the winter surface temperature at the same location, indicating the horizontal advective nature of CIL formation in the area (Kolesnikov, 1953). In addition to advection in the deep area of the sea, the transport of cold waters from the northwest Black Sea shelf across the shelf break in winter was shown to contribute to the formation of the CIL (Filippov, 1968; Staneva and Stanev, 1997). However less is known of the exchanges between the CIL waters and the outer shelf areas in summer, when a surface mixed layer and the underlying seasonal thermocline are formed. Ivanov et al. (1997) suggested that the cross frontal exchange within the CIL is strongly inhibited, so that CIL waters formed in the deep sea (i.e. offshore of the Rim Current) do not replenish the CIL waters onshore of the Rim Current (also known as near-bottom shelf waters, or BSW), due to strong cross frontal gradients in potential vorticity (PV). To the contrary, Shapiro et al. (2011) analysed in-situ observations over the period of 1950-2001 and showed a high correlation between the CIL temperatures in the open sea and outer shelf. However, the statistical methods alone were not able to clearly establish the relation between the cause and the consequences. In this study we use a 3D numerical model of the Black Sea (NEMO-SHELF-BLS) to quantify the exchange of CIL waters between the open sea and the outer northwest Black Sea shelf and to assess its significance for the replenishment of BSW on the outer shelf. The model has a resolution of 1/16º latitude × 1/12º longitude and 33 levels in the vertical. In order to represent near-bottom processes better, the model uses a hybrid

  5. Process-based distributed hydrological modelling of annual floods in the Upper Zambezi using the Desert Flood Index

    NASA Astrophysics Data System (ADS)

    Meinhardt, Markus; Sven, Kralisch; Manfred, Fink; Daniel, Butchart-Kuhlmann; Anthony, Chabala; Melanie, Fleischer; Jörg, Helmschrot; Wilson, Phiri; Tina, Trautmann; Henry, Zimba; Imasiku, Nyambe

    2016-04-01

    Wetland areas are especially sensitive to changes in hydrological conditions. The catchment of the Luanginga River, a tributary of the Upper Zambezi which covers about 33000 km², shows this characteristic in an exemplary way. Ranging from the Angolan highlands to the Barotse floodplain of the Zambezi River , it is characterized by an annual flow regime and extensive wetland areas. Due to its annual flooding with peak times in April, the area features exceptionally fertile soils with high agricultural production and is further known for its rich cultural heritage, making it especially sensitive to changes of hydrological conditions . To identify possible changes related to projected climate and land management change, especially in the area of the floodplain, there is a need to apply a process-based distributed hydrological model of the annual floods . Remote sensing techniques have shown to be appropriate to identify the extend of the important flooding and were used to validate the model in space and time. The results of this research can be used as a basis with which to provide evidence-based advice and information for all decision-makers and stakeholders in the region. For this assessment , such a modelling approach is applied to adequately represent hydrological processes and to address key water resources management issues at sub-basin levels. Introducing a wetland simulation extension, the model allows to represent the annual flood regime of the system and thus to address the effect of climate change and upstream land use changes on flow regimes in the downstream watershed. In order to provide a basis for model validation and calibration, the inundated area was determined using the Desert Flood Index (DFI), which was generated from a time series of Landsat images. We will give a short introduction to the study area and related water resources management problems, present the intended model structure and show first simulations and model validation results

  6. Production and fabrication of vanadium alloys for the radiative divertor program of DIII-D - Annual report input for 1996

    SciTech Connect

    Johnson, W.R.; Smith, J.P.; Stambaugh, R.D.

    1996-10-01

    V-4Cr-4Ti alloy has been selected for use in the manufacture of a portion of the DIII-D Radiative Divertor (RD) upgrade. The production of a 1200-kg ingot of V-4Cr-4Ti alloy has been completed at Teledyne Wah Chang of Albany, Oregon (TWCA) to provide {approximately}800-kg of applicable product forms, and two billets have been extruded from the ingot. Chemical compositions of the ingot and both extruded billets were acceptable. Material from these billets will be converted into product forms suitable for components of the DIII-D Radiative Divertor structure. Joining of V-4Cr-4Ti alloy has been identified as the most critical fabrication issue for its use in the RD Program, and research into several joining methods for fabrication of the RD components, including resistance seam, friction, and electron beam welding, is continuing. Preliminary trials have been successful in the joining of V-alloy to itself by electron beam, resistance, and friction welding processes and to Inconel 625 by friction welding.

  7. Improving solar radiation forecasts from Eta/CPTEC model using statistical post-processing

    NASA Astrophysics Data System (ADS)

    Guarnieri, R. A.; Pereira, E. B.; Chou, S. C.

    Solar radiation forecasts are mainly demanded by the energy sector besides other applications Accurate short-term forecasts of solar energy resources are required for management of co-generation systems and energy dispatch in transmission lines Mesoscale weather forecast models usually have radiation parameterization codes since solar radiation is the main energy source for atmospheric processes The Eta model running operationally in the Brazilian Center of Weather Forecast and Climate Studies CPTEC INPE is a mesoscale model with 40 km horizontal resolution This model has outputs for many meteorological variables including solar radiation incidence on ground These radiation forecasts are nevertheless greatly overestimated As an attempt to improve the forecasts of solar energy resources using Eta model statistical post-processing models or refining models were used Multiple linear regression MLR models were adjusted and artificial neural networks ANN were trained using a statistically selected group of 7 variables predicted by the Eta model not including the Eta solar radiation forecast itself This group of variables expresses the future weather and surface conditions Theoretical solar radiation amount on the top of atmosphere TOA was calculated and used as another input Solar radiation measurements from piranometers Kipp Zonen CM-21 installed on two ground-stations of the SONDA Project were used as the targets to be simulated throughout the adjustment training of the models These measurements were also used

  8. Annual Conference on Nuclear and Space Radiation Effects, 19th, Las Vegas, NV, July 20-22, 1982, Proceedings

    NASA Technical Reports Server (NTRS)

    Long, D. M.

    1982-01-01

    The results of research concerning the effects of nuclear and space radiation are presented. Topics discussed include the basic mechanisms of nuclear and space radiation effects, radiation effects in devices, and radiation effects in microcircuits, including studies of radiation-induced paramagnetic defects in MOS structures, silicon solar cell damage from electrical overstress, radiation-induced charge dynamics in dielectrics, and the enhanced radiation effects on submicron narrow-channel NMOS. Also examined are topics in SGEMP/IEMP phenomena, hardness assurance and testing, energy deposition, desometry, and radiation transport, and single event phenomena. Among others, studies are presented concerning the limits to hardening electronic boxes to IEMP coupling, transient radiation screening of silicon devices using backside laser irradiation, the damage equivalence of electrons, protons, and gamma rays in MOS devices, and the single event upset sensitivity of low power Schottky devices.

  9. Gamma-ray pulsars: Radiation processes in the outer magnetosphere

    NASA Technical Reports Server (NTRS)

    Romani, Roger W.

    1996-01-01

    We describe an emission model for gamma ray pulsars based on curvature radiation-reaction limited charges in the outer magnetosphere. We show how pair production on thermal surface flux can limit the acceleration zones. Estimates for the efficiency of GeV photon production eta gamma and the gamma-ray beaming fraction are derived, including their dependence on pulsar parameters. In general eta gamma increases with pulsar age, but is decreased for low magnetic fields and for small magnetic inclinations. We argue that this produces GeV pulse profiles, curvature spectra and detection statistics consistent with the observations. We also describe the optical through X-ray pulsar synchrotron spectrum and the spectral variations with pulsar phase. A test computation for Vela-like parameters reproduces phase-resolved GeV spectra consistent with those observed by EGRET. Finally we comment on very high energy pulsed emission and particle production and note extensions needed to allow a more complete pulsar model.

  10. SST Variation Due to Interactive Convective-Radiative Processes

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Shie, C.-L.; Johnson, D.; Simpson, J.; Li, X.; Sui, C.-H.

    2000-01-01

    The recent linking of Cloud-Resolving Models (CRMs) to Ocean-Mixed Layer (OML) models has provided a powerful new means of quantifying the role of cloud systems in ocean-atmosphere coupling. This is due to the fact that the CRM can better resolve clouds and cloud systems and allow for explicit cloud-radiation interaction. For example, Anderson (1997) applied an atmospheric forcing associated with a CRM simulated squall line to a 3-D OML model (one way or passive interaction). His results suggested that the spatial variability resulting from the squall forcing can last at least 24 hours when forced with otherwise spatially uniform fluxes. In addition, the sea surface salinity (SSS) variability continuously decreased following the forcing, while some of the SST variability remained when a diurnal mixed layer capped off the surface structure. The forcing used in the OML model, however, focused on shorter time (8 h) and smaller spatial scales (100-120 km). In this study, the 3-D Goddard Cumulus Ensemble Model (GCE; 512 x 512 x 23 cu km, 2-km horizontal resolution) is used to simulate convective active episodes occurring in the Western Pacific warm pool and Eastern Atlantic regions. The model is integrated for seven days, and the simulated results are coupled to an OML model to better understand the impact of precipitation and changes in the planetary boundary layer upon SST variation. We will specifically examine and compare the results of linking the OML model with various spatially-averaged outputs from GCE simulations (i.e., 2 km vs. 10-50 km horizontal resolutions), in order to help understand the SST sensitivity to multi-scale influences. This will allow us to assess the importance of explicitly simulated deep and shallow clouds, as well as the subgrid-scale effects (in coarse-model runs) upon SST variation. Results using both 1-D and 2-D OML models will be evaluated to assess the effects of horizontal advection.

  11. Consistency among microphysics-convection-radiation processes in a numerical forecasting model

    NASA Astrophysics Data System (ADS)

    Bae, Soo Ya; Park, Raeseol; Hong, Song-You

    2016-04-01

    Radiative fluxes are mainly affected by the cloud optical properties calculated with effective radius, water path of hydrometeors, and cloud fraction. A prognostic cloud fraction scheme, which considers the cloud fraction with increments as a result of each physics process, is implemented in the Global/Regional Integrated Model system (GRIMs) (Park et al., 2016). However, the original RRTMG scheme does not consider the hydrometeor information from convection processes, resulting in inconsistency between cloud process and radiation activity. To ensure consistency among physics processes, the amount of hydrometeors from both the cumulus parameterization scheme (CPS) and microphysics schemes is explicitly taken into account in computing radiative fluxes. The effects of this modification are tested for a heavy rainfall over Korea to identify the feedback between the precipitation and radiation processes. It is found that the information of hydrometeors from CPS tends to increase water path, which leads to larger cloud optical depth and cooling. Skill scores of the simulated precipitation in a medium-range forecast testbed confirm benefits of the consistent treatment of hydrometeors in both CPS and radiation processes.

  12. Investigation of radiation keeping property of barite coated cloth via image processing method

    NASA Astrophysics Data System (ADS)

    Kilinçarslan, Ş.; Akkurt, İ.; Molla, T.; Akarslan, F.

    2012-09-01

    Preservative clothes which are able to absorb radiation beam are needed not only for saving people working at radioactive environment but also for saving others from natural and man-made radiation sources we are exposed in daily life. Barite is a mineral which can be used for armour plating because of high atomic numbered element barium constituent of barite. In this study, armour plating property of barite was applied to fabrics. Barite coated fabric having characteristic of keeping radiation was obtained by penetrating barite on cloth via coating method. Radiation keeping property of fabrics obtained was determined via image processing. The results of experiments showed that barite coated fabrics have blocked radiation more than normal fabrics have done.

  13. Investigation of radiation keeping property of barite coated cloth via image processing method

    SciTech Connect

    Kilincarslan, S.; Akkurt, I.; Molla, T.; Akarslan, F.

    2012-09-06

    Preservative clothes which are able to absorb radiation beam are needed not only for saving people working at radioactive environment but also for saving others from natural and man-made radiation sources we are exposed in daily life. Barite is a mineral which can be used for armour plating because of high atomic numbered element barium constituent of barite. In this study, armour plating property of barite was applied to fabrics. Barite coated fabric having characteristic of keeping radiation was obtained by penetrating barite on cloth via coating method. Radiation keeping property of fabrics obtained was determined via image processing. The results of experiments showed that barite coated fabrics have blocked radiation more than normal fabrics have done.

  14. 1986 Annual Conference on Nuclear and Space Radiation Effects, 23rd, Providence, RI, July 21-23, 1986, Proceedings

    NASA Technical Reports Server (NTRS)

    Ellis, Thomas D. (Editor)

    1986-01-01

    The present conference on the effects of nuclear and space radiation on electronic hardware gives attention to topics in the basic mechanisms of radiation effects, dosimetry and energy-dependent effects, electronic device radiation hardness assurance, SOI/SOS radiation effects, spacecraft charging and space radiation, IC radiation effects and hardening, single-event upset (SEU) phenomena and hardening, and EMP/SGEMP/IEMP phenomena. Specific treatments encompass the generation of interface states by ionizing radiation in very thin MOS oxides, the microdosimetry of meson energy deposited on 1-micron sites in Si, total dose radiation and engineering studies, plasma interactions with biased concentrator solar cells, the transient imprint memory effect in MOS memories, mechanisms leading to SEU, and the vaporization and breakdown of thin columns of water.

  15. Fundamentals of thermal radiation heat transfer; Proceedings of the Winter Annual Meeting, New Orleans, LA, December 9-14, 1984

    NASA Astrophysics Data System (ADS)

    Min, T. C.; Chen, J. L. S.

    1984-12-01

    Recent work in the field of radiation heat transfer is addressed in this symposium volume. Three broad topics are considered: analysis and modeling of radiation theory, radiation with a participating medium in a complex geometry, and radiation and/or other modes. Individual papers examine: Hookean and Stokesean implications of radiative stress; effective emissivity of a fluidized bed; mathematical modelling of heat transfer within the furnace of a pulverized coal-fired boiler equipped with platen superheaters; radiative transfer in axisymmetric, finite cylindrical enclosures; thermal behavior in furnaces of complex geometry; analysis of radiative equilibrium in a rectangular enclosure with gray medium; effects of isotropic scattering on melting and solidification of a semiinfinite, semitransparent medium; simultaneous radiation and forced convection in thermally developing turbulent flow through a parallel plate channel; and recent advances in the numerical analysis of dynamic coupled thermoelasticity.

  16. Process for producing radiation-induced self-terminating protective coatings on a substrate

    DOEpatents

    Klebanoff, Leonard E.

    2001-01-01

    A gas and radiation are used to produce a protective coating that is substantially void-free on the molecular scale, self-terminating, and degradation resistant. The process can be used to deposit very thin (.apprxeq.5-20 .ANG.) coatings on critical surfaces needing protection from degradative processes including, corrosion and contamination.

  17. The Influence of Dust-radiation-microphysics Processes on Tropical Cyclone Development

    NASA Astrophysics Data System (ADS)

    Chen, S.; Cheng, C.; Chen, J.; Lin, Y.; Lee, H.; Tsai, I.

    2011-12-01

    Saharan dust can modify the Saharan Air Layer (SAL) and its environment by changing the energy budget through direct and indirect radiative forcing. Scattering and absorption of radiation by suspended dust directly modifies the energy budget in the atmosphere and at the surface. Smaller dust particles can remain suspended in the air for prolonged periods and propagate over the Atlantic Ocean along with SAL. These fine particles can reach an altitude of 8-9 km, where they nucleate ice crystals and transform cloud microphysical properties, indirectly changing the energy budget. Thus, the dust within the air mass is likely to affect the evolution of hurricane properties, life cycles, and the corresponding cloud systems through the dust-cloud-radiation interactions. A tracer model based on the Weather Research and Forecasting model (named WRFT) was developed to study the influence of dust-radiation-microphysics effects on hurricane activities. The dust-radiation effects and a two-moment microphysics scheme with dust particles acting as ice nuclei were implemented into WRFT. In this work, two easterly waves, which were precursors of Tropical Storm Debby and Hurricane Ernesto, during 18-25 August 2006 were studied. Four high-resolution numerical experiments were conducted with the combinations of activating/deactivating dust-radiation and/or dust-microphysics processes. Results from these four experiments are compared to investigate the influence of dust-radiation-microphysics processes on these two storm developments.

  18. Processing line for industrial radiation-thermal synthesis of doped lithium ferrite powders

    NASA Astrophysics Data System (ADS)

    Surzhikov, A. P.; Galtseva, O. V.; Vasendina, E. A.; Vlasov, V. A.; Nikolaev, E. V.

    2016-02-01

    The paper considers the issues of industrial production of doped lithium ferrite powders by radiation-thermal method. A technological scheme of the processing line is suggested. The radiation-thermal technological scheme enables production of powders with technical characteristics close to the required ones under relatively low temperature annealing conditions without intermediate mixing. The optimal conditions of the radiation-thermal synthesis are achieved isothermally under irradiation by the electron beam with energy of 2.5 MeV in the temperature range of 700-750 0C within- 120 min.

  19. Enhancing Cloud Radiative Processes and Radiation Efficiency in the Advanced Research Weather Research and Forecasting (WRF) Model

    SciTech Connect

    Iacono, Michael J.

    2015-03-09

    The objective of this research has been to evaluate and implement enhancements to the computational performance of the RRTMG radiative transfer option in the Advanced Research version of the Weather Research and Forecasting (WRF) model. Efficiency is as essential as accuracy for effective numerical weather prediction, and radiative transfer is a relatively time-consuming component of dynamical models, taking up to 30-50 percent of the total model simulation time. To address this concern, this research has implemented and tested a version of RRTMG that utilizes graphics processing unit (GPU) technology (hereinafter RRTMGPU) to greatly improve its computational performance; thereby permitting either more frequent simulation of radiative effects or other model enhancements. During the early stages of this project the development of RRTMGPU was completed at AER under separate NASA funding to accelerate the code for use in the Goddard Space Flight Center (GSFC) Goddard Earth Observing System GEOS-5 global model. It should be noted that this final report describes results related to the funded portion of the originally proposed work concerning the acceleration of RRTMG with GPUs in WRF. As a k-distribution model, RRTMG is especially well suited to this modification due to its relatively large internal pseudo-spectral (g-point) dimension that, when combined with the horizontal grid vector in the dynamical model, can take great advantage of the GPU capability. Thorough testing under several model configurations has been performed to ensure that RRTMGPU improves WRF model run time while having no significant impact on calculated radiative fluxes and heating rates or on dynamical model fields relative to the RRTMG radiation. The RRTMGPU codes have been provided to NCAR for possible application to the next public release of the WRF forecast model.

  20. Process development studies of the bioconversion of cellulose and production of ethanol. Semi annual report

    SciTech Connect

    Wilke, C.R.; Blanch, H.W.

    1981-04-01

    Progress in the following process development studio is reported: economic evaluation of hydrolysis and ethanol fermentation schemes, economic evaluation of alternative fermentation processes, raw materials evaluation, and evaluation of pretreatment process. Microbiological and enzymatic studies reported are: production of cellulase enzyme from high yielding mutants, hydrolysis reactor development, xylose fermentation, and xylanese production. Fermentation and separation processes include: process development studies on vacuum fermentation and distillation, evaluation of low energy separations processes, large scale hollow fiber reactor development. (MHR)

  1. Solar radiation and clouds - an overview on processes, interactions and trends

    NASA Astrophysics Data System (ADS)

    Quante, M.

    2009-09-01

    This talk will provide an overview regarding the many aspects of the solar radiation-cloud interaction. It will address questions of cloud dynamics, the clouds in radiative transfer as well as the important role the cloud-radiation interaction plays in climate. The state of discussion in some disputed fields will be reported. Before solar radiation reaches the surface of the Earth's continents and oceans, it has to pass the atmosphere consisting of a multitude of gases, particles, and hydrometeors. The prime regulator of the radiation field in the atmosphere is clouds. Thus the cloud radiation interaction is of utmost importance for climate, climate change and radiation driven processes in the biosphere or in photochemistry. Solar radiation is strongly steering the lifecycle (generation, maintenance and dissipation) of clouds. Cloud dynamics and the vertical distribution of energy are dependent on the processes involved. Central aspects of the chain of effects will be outlined in this overview. Clouds reflect and absorb solar radiation, both processes are highly dependent on their radiative properties, thus on the detailed microphysical composition of clouds as well as on their geometrical appearance. The talk will provide an update of the current knowledge and state of discussion with respect to theses properties. Additionally, an actually suggested geo-engineering approach building on the deliberate change of cloud radiative properties will be discussed. One bulk measure of the impact of clouds on the radiation balance in a climatological sense is the so called ‘cloud radiative forcing' (CRF). It allows the assessment of the amount by which the presence of clouds alters the top-of-the-atmosphere (TOA) energy budged. CRF is determined by the difference between the cloud-free radiation budget climatology and the average one over all scene types. Estimates from the Earth Radiation budget Experiment (ERBE) and more recent compilations from satellite climatologies

  2. Effects of colonization processes on genetic diversity: differences between annual plants and tree species.

    PubMed Central

    Austerlitz, F; Mariette, S; Machon, N; Gouyon, P H; Godelle, B

    2000-01-01

    Tree species are striking for their high within-population diversity and low among-population differentiation for nuclear genes. In contrast, annual plants show much more differentiation for nuclear genes but much less diversity than trees. The usual explanation for this difference is that pollen flow, and therefore gene flow, is much higher for trees. This explanation is problematic because it relies on equilibrium hypotheses. Because trees have very recently recolonized temperate areas, they have experienced many foundation events, which usually reduce within-population diversity and increase differentiation. Only extremely high levels of gene flow could counterbalance these successive founder effects. We develop a model to study the impact of life cycle of forest trees, in particular of the length of their juvenile phase, on genetic diversity and differentiation during the glacial period and the following colonization period. We show that both a reasonably high level of pollen flow and the life-cycle characteristics of trees are needed to explain the observed structure of genetic diversity. We also show that gene flow and life cycle both have an impact on maternally inherited cytoplasmic genes, which are characterized both in trees and annual species by much less diversity and much more differentiation than nuclear genes. PMID:10757772

  3. Inter-annual variability of exchange processes at the outer Black Sea shelf

    NASA Astrophysics Data System (ADS)

    Shapiro, Georgy; Wobus, Fred; Yuan, Dongliang; Wang, Zheng

    2014-05-01

    The advection of cold water below the surface mixed layer has a significant role in shaping the properties of the Cold Intermediate Layer (CIL) in the Black Sea, and thus the horizontal redistribution of nutrients. The minimal temperature of the CIL in the southwest deep region of the sea in summer was shown to be lower than the winter surface temperature at the same location, indicating the horizontal advective nature of CIL formation in the area (Kolesnikov, 1953). In addition to advection in the deep area of the sea, the transport of cold waters from the northwest Black Sea shelf across the shelf break in winter was shown to contribute to the formation of the CIL (Filippov, 1968; Staneva and Stanev, 1997). However less is known of the exchanges between the CIL waters and the outer shelf areas in summer, when a surface mixed layer and the underlying seasonal thermocline are formed. Ivanov et al. (1997) suggested that the cross frontal exchange within the CIL is strongly inhibited, so that CIL waters formed in the deep sea (i.e. offshore of the Rim Current) do not replenish the CIL waters onshore of the Rim Current (also known as near-bottom shelf waters, or BSW), due to strong cross frontal gradients in potential vorticity (PV). To the contrary, Shapiro et al. (2011) analysed in-situ observations over the period of 1950-2001 and showed a high correlation between the CIL temperatures in the open sea and outer shelf. However, the statistical methods alone were not able to clearly establish the relation between the cause and the consequences. In this study we use a 3D numerical model of the Black Sea (NEMO-SHELF-BLS) to quantify the exchange of CIL waters between the open sea and the outer northwest Black Sea shelf and to assess its significance for the replenishment of BSW on the outer shelf. The model has a resolution of 1/16º latitude × 1/12º longitude and 33 levels in the vertical. In order to represent near-bottom processes better, the model uses a hybrid

  4. The Collisional and Radiative Processes of the Hydroxyl Radical

    NASA Astrophysics Data System (ADS)

    Steffens, Kristen Lisa

    1995-01-01

    The OH radical is an important species in the chemistry of atmospheric and combustion environments, where an understanding of OH concentration and chemistry is necessary to create and validate chemical models. Laser-induced fluorescence (LIF) is used with great success in OH detection, but OH LIF measurements require a vast knowledge of the collisional and spectroscopic properties of OH. Information is still lacking, especially concerning vibrational levels v^' > 0 of the rm A^2Sigma^+ electronic state. We investigate transition probabilities and collisional processes of these higher vibrational levels. Experimental vibrational band transition probabilities from v^' = 3 and 2 of OH rm A^2Sigma^+ are needed to determine the electronic transition moment for the rm A^2Sigma^+ -rm X^2Pi_{i } system to calculate a consistent set of rotational and vibrational dependent transition probabilities for uses including rm X^2Pi_ {i} temperature determinations and rm A^2Sigma^+ and rm X^2Pi_{i} nascent population determinations. Using LIF in a low -pressure CH_4/O_2 flame, we measured relative emission intensities for vibrational bands (3,0) through (3,5) and (2,0) through (2,6). Our emission intensities have been used in another study to determine the best rm A^2 Sigma^+-rm X^2 Pi_{i} electronic transition moment. For quantitative OH concentration measurements in high pressure flames exciting the predissociative v ^' = 3 level, one must account for vibrational energy transfer (VET). We measure the amounts of VET occurring from v^' = 3 in CH_4/O_2 , CH_4/air, and H _2/O_2 flames at pressures between 14 and 760 Torr. Significant amounts of VET occur in all flames and must be accounted for to get accurate OH concentrations. Stratospheric OH concentration measurement employs OH rm A^2Sigma^+v ^' = 1 excitation, which requires accurate VET and quenching cross sections for major colliders. We use LIF to measure the v^ ' = 1 VET and quenching cross sections for N_2, O_2 and CO_2

  5. Towards a Process-based Representation of Annual Crops Within the Land Surface Model JULES

    NASA Astrophysics Data System (ADS)

    van den Hoof, C.; Vidale, P.

    2008-05-01

    The purpose of this work is to introduce a generic crop structure within the Joint UK Land surface Exchange Scheme JULES (Cox, 1998) that is able to evaluate the interaction between growing crops and the environment at large scales for a wide range of atmospheric conditions. JULES was designed to simulate land surface processes in natural ecosystems. The importance of representing agricultural land within global biosphere models has been pointed out in many studies (De Noblet-Ducoudre et al., 2004; Bondeau 2005 et al.). Prior to any model development, the sensitivity of JULES to morphological and physiological differences between natural vegetation and crops has been investigated by reparameterising a natural C3 grass into a C3 crop. For a case study of fallow versus wheat at Grignon (France), the model output shows important soil water savings after crop harvest at the beginning of the summer. Owing to the lack of a rooting system, the deeper soil moisture cannot contribute anymore to the moisture flux to the atmosphere. On a shorter timescale, the harvest, and by consequence the sudden appearance of bare soil, also disrupt the energy and momentum fluxes between surface and atmosphere. Having established the sensitivity of the JULES system to a crop-like forcing, some components from the crop model SUCROS (Goudriaan and van Laar, 1994) that are relevant to the global water, energy and carbon cycles, have been introduced in JULES. The new version of JULES, denoted by JULES-SUCROS, incorporates crops and natural vegetation within a single modelling framework, without discontinuity in the photosynthesis-assimilation scheme between both vegetation types. Simulations have been performed with JULES-SUCROS for wheat at the Grignon site in current and doubled CO2 atmospheric conditions. Changing atmospheric conditions in JULES-SUCROS affects the sowing date and the length of the growing season. The results show that the positive effect of the CO2 fertilisation partly

  6. Value of increasing film processing time to reduce radiation dose during mammography

    SciTech Connect

    Skubic, S.E.; Yagan, R.; Oravec, D.; Shah, Z. )

    1990-12-01

    We systematically tested the effects on radiation dose and image quality of increasing the mammographic film processing time from the standard 90 sec to 3 min. Hurter and Driffield curves were obtained for a Kodak Min-R-OM1-SO177 screen-film combination processed with Kodak chemistry. Image contrast and radiation dose were measured for two tissue-equivalent breast phantoms. We also compared sequential pairs of mammograms, one processed at 90 sec and one at 3 min, from 44 patients on the basis of nine categories of image quality. Increased processing time reduced breast radiation dose by 30%, increased contrast by 11%, and produced slight overall gains in image quality. Simple modifications can convert a 90-sec processor to a 3-min unit. We recommend that implementation of extended processing be considered, especially by those centers that obtain a large number of screening mammograms. Three-minute film processing can reduce breast radiation dose by 30% and increase contrast by 11% without compromising image quality.

  7. Electromagnetic processes in nucleus-nucleus collisions relating to space radiation research

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1992-01-01

    Most of the papers within this report deal with electromagnetic processes in nucleus-nucleus collisions which are of concern in the space radiation program. In particular, the removal of one and two nucleons via both electromagnetic and strong interaction processes has been extensively investigated. The theory of relativistic Coulomb fission has also been developed. Several papers on quark models also appear. Finally, note that the theoretical methods developed in this work have been directly applied to the task of radiation protection of astronauts. This has been done by parameterizing the theoretical formalism in such a fashion that it can be used in cosmic ray transport codes.

  8. General description of electromagnetic radiation processes based on instantaneous charge acceleration in ''endpoints''

    SciTech Connect

    James, Clancy W.; Falcke, Heino; Huege, Tim; Ludwig, Marianne

    2011-11-15

    We present a methodology for calculating the electromagnetic radiation from accelerated charged particles. Our formulation - the 'endpoint formulation' - combines numerous results developed in the literature in relation to radiation arising from particle acceleration using a complete, and completely general, treatment. We do this by describing particle motion via a series of discrete, instantaneous acceleration events, or 'endpoints', with each such event being treated as a source of emission. This method implicitly allows for particle creation and destruction, and is suited to direct numerical implementation in either the time or frequency domains. In this paper we demonstrate the complete generality of our method for calculating the radiated field from charged particle acceleration, and show how it reduces to the classical named radiation processes such as synchrotron, Tamm's description of Vavilov-Cherenkov, and transition radiation under appropriate limits. Using this formulation, we are immediately able to answer outstanding questions regarding the phenomenology of radio emission from ultra-high-energy particle interactions in both the earth's atmosphere and the moon. In particular, our formulation makes it apparent that the dominant emission component of the Askaryan effect (coherent radio-wave radiation from high-energy particle cascades in dense media) comes from coherent 'bremsstrahlung' from particle acceleration, rather than coherent Vavilov-Cherenkov radiation.

  9. Effects of doubled carbon dioxide on rainfall responses to radiative processes of water clouds

    NASA Astrophysics Data System (ADS)

    Li, Xiaofan; Li, Tingting; Lou, Lingyun

    2014-12-01

    The effects of doubled carbon dioxide on rainfall responses to radiative processes of water clouds are investigated in this study. Two groups of two-dimensional cloud-resolving model sensitivity experiments with regard to pre-summer heavy rainfall around the summer solstice and tropical rainfall around the winter solstice are conducted and their five-day averages over the model domain are analyzed. In the presence of radiative effects of ice clouds, doubled carbon dioxide changes pre-summer rainfall from the decrease associated with the enhanced atmospheric cooling to the increase associated with the enhanced infrared cooling as a result of the exclusion of radiative effects of water clouds. Doubled carbon dioxide leads to the reduction in tropical rainfall, caused by the removal of radiative effects of water clouds through the suppressed infrared cooling. In the absence of radiative effects of ice clouds, doubled carbon dioxide changes pre-summer rainfall from the increase associated with the strengthened atmospheric warming to the decrease associated with the weakened release of latent heat caused by the elimination of radiative effects of water clouds. The exclusion of radiative effects of water clouds increases tropical rainfall through the strengthened infrared cooling, which is insensitive to the change in carbon dioxide.

  10. Reservoir characterization and process monitoring with EM methods. 1993 Annual report

    SciTech Connect

    Wilt, M.

    1994-09-01

    During the past four years at Lawrence Livermore National Laboratory (LLNL) the authors have applied the EM induction method to the problem of thermal front tracking during EOR operations. During this past year, they have also turned their attention to the larger, but related, problem of petroleum reservoir characterization. As in the past, this research is a collaborative effort. The main focus of activities at LLNL is hardware development, field measurement and geological interpretation of the results. The authors are dependent on others for theoretical and software development, geological information and the availability of sites to test field systems. Collaborative interdependency serves to make research dollars stretch further and allows completion of the tasks in a timely manner. In this annual report the authors discuss the progress in the development of numerical modeling codes, describe improvements to the field system and present some field results.

  11. Optical radiation hazards of laser welding processes. Part 1: Neodymium-YAG laser.

    PubMed

    Rockwell, R J; Moss, C E

    1983-08-01

    High power laser devices are being used for numerous metalworking processes such as welding, cutting and heat treating. Such laser devices are totally enclosed either by the manufacturer or the end-user. When this is done, the total laser system is usually certified by the manufacturer following the federal requirements of the Code of Federal Regulations (CFR) 1040.10 and 10.40.11 as a Class I laser system. Similarly, the end-user may also reclassify an enclosed high-power laser into the Class I category following the requirements of the American National Standards Institute (ANSI) Z-136.1 (1980) standard. There are, however, numerous industrial laser applications where Class IV systems are required to be used in an unenclosed manner. In such applications, there is concern for both ocular and skin hazards caused by direct and scattered laser radiation, as well as potential hazards caused by the optical radiation created by the laser beam's interaction with the metal (i.e. the plume radiation). Radiant energy measurements are reported for both the scattered laser radiation and the resultant plume radiations which were produced during typical unenclosed Class IV Neodymium-YAG laser welding processes. Evaluation of the plume radiation was done with both radiometric and spectroradiometric measurement equipment. The data obtained were compared to applicable safety standards. PMID:6688700

  12. Radiative transfer in real atmospheres. [the implications for recognition processing of multispectral remote sensing data

    NASA Technical Reports Server (NTRS)

    Turner, R. E.

    1974-01-01

    The problem of multiple radiation scattering in an atmosphere characterized by various amounts of aerosol absorption and different particle size distributions was investigated. The visible part of the spectrum was emphasized, including the effect of ozone absorption. An atmosphere bounded by a nonhomogenous, Lambertian surface was also studied, along with the effect of background radiation on target in terms of various atmopheric and geometric conditions. Results of the investigation indicate that comtaminated atmospheres can change the radiation field by a considerable amount, and that the effect of non-uniform surface significantly alters the intrinsic radiation from a target element. The implications of these results for the recognition processing of multispectral remote sensing data is discussed.

  13. Administration of the Radiation Control for Health and Safety Act of 1968, Public Law 90-602, (1987 annual report). Report for January-December 1987

    SciTech Connect

    Not Available

    1988-04-01

    This document is an annual report submitted to the President for transmittal to the Congress. The Food and Drug Administration, through its Center for Devices and Radiological Health, is responsible for the day-to-day administration of the Radiation Control for Health and Safety Act of 1968. The report provides a summary of the operations of the Center in carrying out that responsibility for calendar year 1987. In reviewing the operations of the CDRH as reported in the document, it should be kept in mind that the day-to-day administration of the Act is only part of the Center's function. Other responsibilities include the administration and enforcement of the 1976 Medical Device Amendments to the Federal Food, Drug, and Cosmetic Act (not covered in the report). Manufacturers of electronic products are required by 21 CFR 1002.20 to report accidental radiation occurrences to the CDRH. The Center no longer maintains a Radiation Incidents Registry, since accidental radiation occurrences are reported through the Device Experience Network (DEN) and through the requirements of the Medical Device Reporting (MDR) regulations.

  14. 1990 IEEE Annual Conference on Nuclear and Space Radiation Effects, 27th, Reno, NV, July 16-20, 1990, Proceedings

    NASA Technical Reports Server (NTRS)

    Fleetwood, Daniel M. (Editor)

    1990-01-01

    Various papers on nuclear and space radiation effects are presented. The general topics addressed include: basic mechanisms of radiation effects, dosimetry and energy-dependent effects, hardness assurance and testing techniques, single-event upset and latchup, isolation technologies, device and integrated circuit effects and hardening, spacecraft charging and electromagnetic effects.

  15. Coupling Aerosol-Cloud-Radiative Processes in the WRF-Chem Model: Investigating the Radiative Impact of Elevated Point Sources

    SciTech Connect

    Chapman, Elaine G.; Gustafson, William I.; Easter, Richard C.; Barnard, James C.; Ghan, Steven J.; Pekour, Mikhail S.; Fast, Jerome D.

    2009-02-01

    The local and regional influence of elevated point sources on summertime aerosol forcing and cloud-aerosol interactions in northeastern North America was investigated using the WRF-Chem community model. The direct effects of aerosols on incoming solar radiation were simulated using existing modules to relate aerosol sizes and chemical composition to aerosol optical properties. Indirect effects were simulated by adding a prognostic treatment of cloud droplet number and adding modules that activate aerosol particles to form cloud droplets, simulate aqueous phase chemistry, and tie a two-moment treatment of cloud water (cloud water mass and cloud droplet number) to an existing radiation scheme. Fully interactive feedbacks thus were created within the modified model, with aerosols affecting cloud droplet number and cloud radiative properties, and clouds altering aerosol size and composition via aqueous processes, wet scavenging, and gas-phase-related photolytic processes. Comparisons of a baseline simulation with observations show that the model captured the general temporal cycle of aerosol optical depths (AODs) and produced clouds of comparable thickness to observations at approximately the proper times and places. The model slightly overpredicted SO2 mixing ratios and PM2.5 mass, but reproduced the range of observed SO2 to sulfate aerosol ratios, suggesting that atmospheric oxidation processes leading to aerosol sulfate formation are captured in the model. The baseline simulation was compared to a sensitivity simulation in which all emissions at model levels above the surface layer were set to zero, thus removing stack emissions. Instantaneous, site-specific differences for aerosol and cloud related properties between the two simulations could be quite large, as removing above-surface emission sources influenced when and where clouds formed within the modeling domain. When summed spatially over the finest resolution model domain (the extent of which corresponds to

  16. Amorphous silicon batch process cost analysis. Annual subcontract report, 11 March 1991--28 February 1993

    SciTech Connect

    Whisnant, R.A.; Sherring, C.

    1993-08-01

    This report describes the development of baseline manufacturing cost data to assist PVMaT monitoring teams in assessing current and future subcontracts, which an emphasis on commercialization and production. A process for the manufacture of a single-junction, large-area, a Si module was modeled using an existing Research Triangle Institute (RTI) computer model. The model estimates a required, or breakeven, price for the module based on its production process and the financial structure of the company operating the process. Sufficient detail on cost drivers is presented so the relationship of the process features and business characteristics can be related to the estimated required price.

  17. WASTE PROCESSING ANNUAL NUCLEAR SAFETY RELATED R AND D REPORT FOR CY2008

    SciTech Connect

    Fellinger, A.

    2009-10-15

    The Engineering and Technology Office of Waste Processing identifies and reduces engineering and technical risks associated with key waste processing project decisions. The risks, and actions taken to mitigate those risks, are determined through technology readiness assessments, program reviews, technology information exchanges, external technical reviews, technical assistance, and targeted technology development and deployment (TDD). The Office of Waste Processing TDD program prioritizes and approves research and development scopes of work that address nuclear safety related to processing of highly radioactive nuclear wastes. Thirteen of the thirty-five R&D approved work scopes in FY2009 relate directly to nuclear safety, and are presented in this report.

  18. 21 CFR 179.39 - Ultraviolet radiation for the processing and treatment of food.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... products Without ozone production: high fat-content food irradiated in vacuum or in an inert atmosphere... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ultraviolet radiation for the processing and treatment of food. 179.39 Section 179.39 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...

  19. 21 CFR 179.39 - Ultraviolet radiation for the processing and treatment of food.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... products Without ozone production: high fat-content food irradiated in vacuum or in an inert atmosphere... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ultraviolet radiation for the processing and treatment of food. 179.39 Section 179.39 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...

  20. Ninth Annual Warren K. Sinclair Keynote Address: effects of childhood radiation exposure: an issue from computed tomography scans to Fukushima.

    PubMed

    Mettler, Fred A; Constine, Louis S; Nosske, Dietmar; Shore, Roy E

    2013-11-01

    The acute and chronic effects of radiation on children have been and will continue to be of great social, public health, scientific, and clinical importance. The focus of interest on ionizing radiation and children has been clear for over half a century and ranges from the effects of fallout from nuclear weapons testing to exposures from accidents, natural radiation, and medical procedures. There is a loosely stated notion that "children are three to five times more sensitive to radiation than adults." Is this really true? In fact, children are at greater risk for some health effects, but not all. For a few sequelae, children may be more resistant than adults. Which are those effects? How and why do they occur? While there are clear instances of increased risk of some radiation-induced tumors in children compared to adults, there are other tumor types in which there appears to be little or no difference in risk by age at exposure and some in which published models that assume the same relative increase in risks for child compared to adult exposures apply to nearly all tumor types are not supported by the scientific data. The United Nations Scientific Committee on Effects of Atomic Radiation (UNSCEAR) has a task group producing a comprehensive report on the subject. The factors to be considered include relevant radiation sources; developmental anatomy and physiology; dosimetry; and stochastic, deterministic, and hereditary effects. PMID:24077040

  1. Role of density ripples to resonant Terahertz radiation excitation in laser beating process

    NASA Astrophysics Data System (ADS)

    Malik, Anil K.; Tomar, Sanjay K.; Malik, Hitendra K.

    2012-10-01

    The Terahertz (THz) radiation has gained much attention of the researchers due to its applications in material characterization, imaging, topography and remote sensing, chemical and security identification, etc. Plasma based THz schemes are attractive because they are capable of producing high power radiation. Several experiments have employed plasma as a medium for the THz radiation generation using sub-picoseconds laser pulses and energetic electron beams. The role of obliqueness of the ripples in plasma density to the THz radiation generation in the process of laser beating is clarified. For this, we use two spatial-super-Gaussian lasers (different indices) having different frequencies and wave numbers but the same field amplitudes. Due to intensity gradient in transverse direction and obliqueness of the density ripples, a transverse component of nonlinear ponderomotive force is realized that produces transverse oscillatory current. This nonlinear current oscillating at beating frequency produces the THz radiation at the beating frequency. We discuss in detail the efficiency of the scheme and power and frequency of the THz radiation with due importance of the density ripples.

  2. A Markov decision process approach to temporal modulation of dose fractions in radiation therapy planning

    NASA Astrophysics Data System (ADS)

    Kim, M.; Ghate, A.; Phillips, M. H.

    2009-07-01

    The current state of the art in cancer treatment by radiation optimizes beam intensity spatially such that tumors receive high dose radiation whereas damage to nearby healthy tissues is minimized. It is common practice to deliver the radiation over several weeks, where the daily dose is a small constant fraction of the total planned. Such a 'fractionation schedule' is based on traditional models of radiobiological response where normal tissue cells possess the ability to repair sublethal damage done by radiation. This capability is significantly less prominent in tumors. Recent advances in quantitative functional imaging and biological markers are providing new opportunities to measure patient response to radiation over the treatment course. This opens the door for designing fractionation schedules that take into account the patient's cumulative response to radiation up to a particular treatment day in determining the fraction on that day. We propose a novel approach that, for the first time, mathematically explores the benefits of such fractionation schemes. This is achieved by building a stylistic Markov decision process (MDP) model, which incorporates some key features of the problem through intuitive choices of state and action spaces, as well as transition probability and reward functions. The structure of optimal policies for this MDP model is explored through several simple numerical examples.

  3. Theoretical studies relating to the interaction of radiation with matter: Atomic collision processes occurring in the presence of radiation fields

    NASA Astrophysics Data System (ADS)

    1980-10-01

    Work is reported in the areas of: (1) collisionally-aided radiative excitation; (2) model potential calculations in atom-field-radiation systems; (3) coherence effects in radiative collisions; (4) two level atom radiation pulse; (5) resonance fluorescence in three level systems; (6) modulation spectroscopy; and (7) effects of collisions on atomic coherences.

  4. Effect of radiation process on antinutrients and HCl extractability of calcium, phosphorus and iron during processing and storage

    NASA Astrophysics Data System (ADS)

    Mohamed, ElShazali Ahmed; Abdelraheem Ali, Nahid; Ahmed, Salma Hashim; Mohamed Ahmed, Isam A.; Babiker, Elfadil E.

    2010-07-01

    Whole and dehulled flours of millet cultivars Ashana and Dembi were stored for 30 and 60 days before and after radiation and/or cooking. Phytic acid and polyphenols contents were assayed for all treatments. The results revealed that the storage period was found to have no effect on phytate and polyphenols contents. Moreover, dehulling of the grains reduced more than 50% of phytate and polyphenols of both cultivars. Cooking of the raw whole and dehulled flour significantly ( P≤0.05) reduced phytate and polyphenols contents for both cultivars. Radiation process alone had no effect on phytate and polyphenols contents but when followed by cooking significantly ( P≤0.05) reduced the level of such antinutrients for the whole and dehulled flour of both cultivars. Dehulling alone significantly ( P≤0.05) decreased Ca and P content but slightly decreased Fe content. Radiation alone or in combination with cooking was found to have slight effect on minerals content of the whole and dehulled raw flour for both cultivars. Cooking alone or in combination with radiation of whole or dehulled raw flour significantly ( P≤0.05) improved the extractable Ca but had no significant ( P≤0.05) effect on extractable P and Fe for both cultivars.

  5. Adaptive information processing in auditory cortex. Annual report, 1 June 1987-31 May 1988

    SciTech Connect

    Weinberger, N.M.

    1988-05-31

    The fact that learning induces frequency-specific modification of receptive fields in auditory cortex implies that the functional organization of auditory (and perhaps other sensory) cortex comprises an adaptively-constituted information base. This project initiates the first systematic investigation of adaptive information processing in cerebral cortex. A major goal is to determine the circumstances under which adaptive information processing is induced by experience. This project also addresses central hypotheses about rules that govern adaptive information processing, at three levels of spatial scale: (a) parallel processing in different auditory fields: (b) modular processing in different cortical lamina within fields; (c) local processing in different neurons within the same locus within lamina. The author emphasized determining the learning circumstances under which adaptive information processing is invoked by the brain. Current studies reveal that the frequency receptive fields of neurons in the auditory cortex, and the physiologically plastic magnocellular medial geniculate nucleus, develop frequency-specific modification such that maximal shifts in tuning are at or adjacent to the signal frequency. Further, this adaptive re-tuning of neurons develops rapidly during habituation, classical conditioning, and instrumental avoidance conditioning. The generality of re-tuning has established that AIP during learning represents a general brain strategy for the acquisition and subsequent processing of information.

  6. Developing and Implementing a Process for the Review of Nonacademic Units. AIR 1988 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Brown, Marilyn K.

    The process of evaluating college academic-support units is described, and the experience of the University of Maryland (College Park) with such a program is discussed. A review of the literature discusses six models: the goal-attainment model, the systems model, the process model, the multiple-constituency approach, the Goodman and Pennings…

  7. Effect of γ radiation processing on fungal growth and quality characteristcs of millet grains.

    PubMed

    Mahmoud, Nagat S; Awad, Sahar H; Madani, Rayan M A; Osman, Fahmi A; Elmamoun, Khalid; Hassan, Amro B

    2016-05-01

    The aim of this study was to evaluate the effect of gamma radiation processing of millet grains on fungal incidence, germination, free fatty acids content, protein solubility, digestible protein, and antinutritional factors (tannin and phytic acid). The grains were exposed to gamma radiation at doses 0.25, 0.5, 0.75, 1.0, and 2.0 kGy. Obtained results revealed that radiation of millet grains at a dose level higher than 0.5 kGy caused significant (P < 0.05) reduction on the percentage of fungal incidence and the free fatty acid of the seeds, while, no significant change in the germination capacity was observed of the grains after radiation. Additionally, the radiation process caused significant (P < 0.05) reduction on both tannins and phytic acid content and gradual increment on in vitro protein digestibility of the grains. On the other hand, the treatments significantly (P < 0.05) increased the protein solubility of the grains. Obtained results indicate that gamma irradiation might improve the quality characteristics of millet grains, and can be used as a postharvest method for disinfestations and decontamination of millet grains. PMID:27247763

  8. Universal statistical approach to radiative and collisional processes with multielectron ions in plasmas

    NASA Astrophysics Data System (ADS)

    Demura, A. V.; Kadomtsev, M. B.; Lisitsa, V. S.; Shurygin, V. A.

    2015-06-01

    The universal statistical approach for calculation of radiative and collisional processes with multielectron ions in plasmas is developed. It is based on the atomic structure representation similar to that used in a condensed medium. The distribution of local atomic electron density determines the set of elementary excitations with classical plasma frequency. The statistical method is tested by the calculations of the total electron impact single ionization cross-sections, ionization rates and radiative losses of various ions. In the coronal limit the radiative losses of heavy plasma impurities with any type of multielectron ions are determined by the excitation of collective atomic oscillations due to collisions with plasma electrons. It is shown that for low plasma densities the tungsten ions total radiative loss scatter within universal statistical approach does not exceed similar results of current complex numerical codes in the wide range of plasma temperatures. The general expression for the radiative losses in the case of the intermediate state between limiting cases of coronal and Boltzmann population distributions is derived as well. The total electron impact ionization cross-sections and ionization rates for ions of various charge stages for a wide range of elements from Ar to U are compared with experimental and conventional complex code data showing satisfactory agreement. As the universal statistical method operates in terms of collective excitations, it implicitly includes direct and indirect ionization processes.

  9. The Annual Cosmic-Radiation Intensities 1391 - 2014; The Annual Heliospheric Magnetic Field Strengths 1391 - 1983, and Identification of Solar Cosmic-Ray Events in the Cosmogenic Record 1800 - 1983

    NASA Astrophysics Data System (ADS)

    McCracken, K. G.; Beer, J.

    2015-10-01

    The annual cosmogenic ^{10}Be ice-core data from Dye 3 and the North Greenland Ice-core Project (NGRIP), and neutron-monitor data, 1951 - 2014, are combined to yield a record of the annual cosmic-ray intensity, 1391 - 2014. These data were then used to estimate the intensity of the heliospheric magnetic field (HMF), 1391 - 1983. All of these annual data are provided in the Electronic Supplementary Material. Analysis of these annual data shows that there were significant impulsive increases in ^{10}Be production in the year following the very large solar cosmic-ray events of 1942, 1949, and 1956. There was an additional enhancement that we attribute to six high-altitude nuclear explosions in 1962. All of these enhancements result in underestimates of the strength of the HMF. An identification process is defined, resulting in a total of seven impulsive ^{10}Be events in the interval 1800 - 1942 prior to the first detection of a solar cosmic-ray event using ionization chambers. Excision of the ^{10}Be impulsive enhancements yields a new estimate of the HMF, designated B(PCR-2). Five of the seven ^{10}Be enhancements prior to 1941 are well correlated with the occurrence of very great geomagnetic storms. It is shown that a solar cosmic-ray event similar to that of 25 July 1946, and occurring in the middle of the second or third year of the solar cycle, may merge with the initial decreasing phase of the 11-year cycle in cosmic-ray intensity and be unlikely to be detected in the ^{10}Be data. It is concluded that the occurrence rate for solar energetic-particle (SEP) events such as that on 23 February 1956 is about seven per century, and that there is an upper limit to the size of solar cosmic-ray events.

  10. Metals Processing Laboratory Users (MPLUS) Facility Annual Report FY 2002 (October 1, 2001-September 30, 2002)

    SciTech Connect

    Angelini, P

    2004-04-27

    The Metals Processing Laboratory Users Facility (MPLUS) is a Department of Energy (DOE), Energy Efficiency and Renewable Energy, Industrial Technologies Program, user facility designated to assist researchers in key industries, universities, and federal laboratories in improving energy efficiency, improving environmental aspects, and increasing competitiveness. The goal of MPLUS is to provide access to the specialized technical expertise and equipment needed to solve metals processing issues that limit the development and implementation of emerging metals processing technologies. The scope of work can also extend to other types of materials. MPLUS has four primary user centers: (1) Processing--casting, powder metallurgy, deformation processing (including extrusion, forging, rolling), melting, thermomechanical processing, and high-density infrared processing; (2) Joining--welding, monitoring and control, solidification, brazing, and bonding; (3) Characterization--corrosion, mechanical properties, fracture mechanics, microstructure, nondestructive examination, computer-controlled dilatometry, and emissivity; and (4) Materials/Process Modeling--mathematical design and analyses, high-performance computing, process modeling, solidification/deformation, microstructure evolution, thermodynamic and kinetic, and materials databases A fully integrated approach provides researchers with unique opportunities to address technologically related issues to solve metals processing problems and probe new technologies. Access is also available to 16 additional Oak Ridge National Laboratory (ORNL) user facilities ranging from state-of-the-art materials characterization capabilities, and high-performance computing to manufacturing technologies. MPLUS can be accessed through a standardized user-submitted proposal and a user agreement. Nonproprietary (open) or proprietary proposals can be submitted. For open research and development, access to capabilities is provided free of charge

  11. Metals Processing Laboratory Users (MPLUS) Facility Annual Report: October 1, 2000 through September 30, 2001

    SciTech Connect

    Angelini, P

    2004-04-27

    The Metals Processing Laboratory Users Facility (MPLUS) is a Department of Energy (DOE), Energy Efficiency and Renewable Energy, Industrial Technologies Program user facility designated to assist researchers in key industries, universities, and federal laboratories in improving energy efficiency, improving environmental aspects, and increasing competitiveness. The goal of MPLUS is to provide access to the specialized technical expertise and equipment needed to solve metals processing issues that limit the development and implementation of emerging metals processing technologies. The scope of work can also extend to other types of materials. MPLUS has four primary User Centers including: (1) Processing--casting, powder metallurgy, deformation processing including (extrusion, forging, rolling), melting, thermomechanical processing, high density infrared processing; (2) Joining--welding, monitoring and control, solidification, brazing, bonding; (3) Characterization--corrosion, mechanical properties, fracture mechanics, microstructure, nondestructive examination, computer-controlled dilatometry, and emissivity; (4) Materials/Process Modeling--mathematical design and analyses, high performance computing, process modeling, solidification/deformation, microstructure evolution, thermodynamic and kinetic, and materials data bases. A fully integrated approach provides researchers with unique opportunities to address technologically related issues to solve metals processing problems and probe new technologies. Access is also available to 16 additional Oak Ridge National Laboratory (ORNL) user facilities ranging from state of the art materials characterization capabilities, high performance computing, to manufacturing technologies. MPLUS can be accessed through a standardized User-submitted Proposal and a User Agreement. Nonproprietary (open) or proprietary proposals can be submitted. For open research and development, access to capabilities is provides free of charge while

  12. Electrochemical processes for in-situ treatment of contaminated soils. 1998 annual progress report

    SciTech Connect

    Huang, C.P.

    1998-06-01

    'This research project is to develop electrochemical processes for in-situ treatment of contaminated soils. Specifically, it is to study electrokinetic (EK) and electro-Fento (EF) processes and to integrate these processes for the treatment of soils containing mixed contaminants. The objectives are: (1) To study important parameters controlling the mobilization and the transport of selected organics and metals in soils by the electrokinetic (EK) process. Factors to be studied include field strength, pH, ionic strength, soil washing agents, types of organic and metal contaminants, and soil surface properties such as cation exchange capacity(CEC), soil organic content, soil moisture content, soil composition, and surface charge. (2) To study the important factors governing the oxidation of selected organic contaminants by the electro-Fenton (EF) process. Parameters such as pH, surface area and the configuration of working electrode, oxygen concentration, ferrous ion, and temperature that may affect the performance of the EF process will be investigated. (3) To understand the mechanism of the oxidation of selected organic contaminants by the electro-Fenton oxidation process.'

  13. Measurements of the flame emissivity and radiative properties of particulate medium in pulverized-coal-fired boiler furnaces by image processing of visible radiation

    SciTech Connect

    Chun Lou; Huai-Chun Zhou; Peng-Feng Yu; Zhi-Wei Jiang

    2007-07-01

    Due to the complicated processes for coal particles burning in industrial furnaces, their radiative properties, such as the absorption and scattering coefficients, which are essential to make reliable calculation of radiative transfer in combustion computation, are hard to be given exactly by the existing methods. In this paper, multiple color image detectors were used to capture approximately red, green, and blue monochromatic radiative intensity images in the visible wavelength region, and the flame emissivity and the radiative properties of the particulate media in three pulverized-coal-fired boiler furnaces were got from the flame images. It was shown that as the load increased, the flame emissivity and the radiative properties increased too; these radiative parameters had the largest values near the burner zone, and decreased along the combustion process. Compared with the combustion medium with a low-volatile anthracite coal burning in a 670 t/h boiler, the emissivity and the absorption coefficient of the medium with a high-volatile bituminous coal burning in a 1025 t/h boiler were smaller near the outlet zone, but were larger near the burner zone of the furnace, due to the significant contribution of soot to the radiation. This work will be of practical importance in modeling and calculating the radiative heat transfer in combustion processes, and improving the technology for in situ, multi-dimensional visualization of large-scale combustion processes in coal-fired furnaces of power plants. 18 refs., 10 figs., 8 tabs.

  14. A Radiation-Hard Analog Memory In The AVLSI-RA Process

    SciTech Connect

    Britton, C.L. Jr.; Wintenberg, A.L.; Read, K.F.; Simpson, M.L.; Young, G.R.; Clonts, L.G., Kennedy, E.J., Smith, R.S., Swann, B.K.; Musser, J.A.

    1995-12-31

    A radiation hardened analog memory for an Interpolating Pad Camber has been designed at Oak Ridge National Laboratory and fabricated by Harris Semiconductor in the AVLSI-RA CMOS process. The goal was to develop a rad-hard analog pipeline that would deliver approximately 9-bit performance, a readout settling time of 500ns following read enable, an input and output dynamic range of +/-2.25V, a corrected rms pedestal of approximately 5mV or less, and a power dissipation of less than 10mW/channel. The pre- and post-radiation measurements to 5MRad are presented.

  15. E-Beam Processing of Polymer Matrix Composites for Multifunctional Radiation Shielding

    NASA Technical Reports Server (NTRS)

    Hou, Tan-Hung; Wilson, John W.; Jensen, Brian J.; Thibeault, Sheila A.; Chang, Chie K.; Kiefer, Richard L.

    2005-01-01

    Aliphatic polymers were identified as optimum radiation shielding polymeric materials for building multifunctional structural elements for in-space habitats. Conceptual damage tolerant configurations of polyolefins have been proposed, but many manufacturing issues relied on methods and materials which have sub-optimal radiation shielding characteristics (for example, epoxy matrix and adhesives). In the present approach, we shall investigate e-beam processing technologies for inclusion of high-strength aliphatic polymer reinforcement structures into a highly cross-linked polyolefin matrix. This paper reports the baseline thermo-mechanical properties of low density polyethylene and highly crystallized polyethylene.

  16. Coherent control of radiation patterns of nonlinear multiphoton processes in nanoparticles

    PubMed Central

    Papoff, Francesco; McArthur, Duncan; Hourahine, Ben

    2015-01-01

    We propose a scheme for the coherent control of light waves and currents in metallic nanospheres which applies independently of the nonlinear multiphoton processes at the origin of waves and currents. We derive conditions on the external control field which enable us to change the radiation pattern and suppress radiative losses or to reduce absorption, enabling the particle to behave as a perfect scatterer or as a perfect absorber. The control introduces narrow features in the response of the particles that result in high sensitivity to small variations in the local environment, including subwavelength spatial shifts. PMID:26155833

  17. Scaled physical model studies of the steam drive process. First annual report, September 1977-September 1978

    SciTech Connect

    Doscher, T M

    1980-12-01

    Scaling laws of the heat transport mechanism in steam displacement processes are developed based upon an integral energy balance equation. Unlike the differential approach adopted by previous workers, the above scaling laws do not necessitate the use of any empirical correction factor as has been done in previous scaling calculations. The results provide a complete and consistent scale-down of the energy transport behavior, which is the critical mechanism for the success of a steam injection process. In the course of the study, the scaling problems associated with relative permeability and capillary pressure are also discussed. A method which has often been used in scaling nonthermal displacement processes is applied to reduce errors due to scaling in relative permeability. Both dimensional and inspectional analyses are applied to illustrate their use in steam processes. Scale-up laws appeared in the literature and those used in this study are compared and numerical examples are given.

  18. UNITED STATES DEPARTMENT OF ENERGY OFFICE OF ENVIRONMENTAL MANAGEMENT WASTE PROCESSING ANNUAL TECHNOLOGY DEVELOPMENT REPORT 2008

    SciTech Connect

    Bush, S.

    2009-11-05

    The Office of Waste Processing identifies and reduces engineering and technical risks and uncertainties of the waste processing programs and projects of the Department of Energy's Environmental Management (EM) mission through the timely development of solutions to technical issues. The risks, and actions taken to mitigate those risks, are determined through technology readiness assessments, program reviews, technology information exchanges, external technical reviews, technical assistance, and targeted technology development and deployment. The Office of Waste Processing works with other DOE Headquarters offices and project and field organizations to proactively evaluate technical needs, identify multi-site solutions, and improve the technology and engineering associated with project and contract management. Participants in this program are empowered with the authority, resources, and training to implement their defined priorities, roles, and responsibilities. The Office of Waste Processing Multi-Year Program Plan (MYPP) supports the goals and objectives of the U.S. Department of Energy (DOE) - Office of Environmental Management Engineering and Technology Roadmap by providing direction for technology enhancement, development, and demonstration that will lead to a reduction of technical risks and uncertainties in EM waste processing activities. The MYPP summarizes the program areas and the scope of activities within each program area proposed for the next five years to improve safety and reduce costs and environmental impacts associated with waste processing; authorized budget levels will impact how much of the scope of activities can be executed, on a year-to-year basis. Waste Processing Program activities within the Roadmap and the MYPP are described in these seven program areas: (1) Improved Waste Storage Technology; (2) Reliable and Efficient Waste Retrieval Technologies; (3) Enhanced Tank Closure Processes; (4) Next-Generation Pretreatment Solutions; (5

  19. Numerical prediction of radiation heat transfer in optoelectronics hermetic packaging process

    NASA Astrophysics Data System (ADS)

    Saha, Chinmoy P.; Zhang, Daming; Liu, Sheng

    2005-03-01

    Hermetic packaging of the high-speed optoelectronics devices is important not only for robustness but also to protect the device from adverse operational environments and ensure reliable communications. We have developed a complete hermetic packaging assembly process for a photonic Mini-DIL module of 10.0Gbps type. We have developed and simulated the step by step fluxless reflow soldering process (pick and place) of the whole mini-module package and finally, the hermetic sealing by Finite Element Analysis (FEA) simulation. A commercially available, general purpose, finite element program - ABAQUS has been used along with Altair HyperWorks as pre and post processor for this numerical simulation. The actual 3-D model has been simplified to the 2-D model for the hermetic sealing, radiation heat transfer prediction to reduce computational complicacy. During the sealing process at a high temperature, there is a possibility of considerable heat transfer from the module top sealing cap to the high temperature susceptible LD (Laser Diode). In the event of a critical temperature the LD may suffer malfunction and eventual destruction. Radiation along with the conduction heat transfer mechanism has been modeled for this sealing to predict the temperature variation as a result of heat transfer from wledspots to the LD. Various issues with cavity radiations such as, effect of radiation view factor, surface blocking and surface emissivity have been considered and results discussed. The convection mechanism has been neglected considering the hermeticity of the sealing.

  20. From research to industry — The establishment of a radiation processing industry in South Africa

    NASA Astrophysics Data System (ADS)

    Plessis, T. A. Du; Stevens, RCB

    In the late sixties the South African Atomic Energy Board in pursuing its objectives to promote the peaceful application of nuclear energy in general, established a research group with the specific purpose of investigating and developing radiation processing as a new technique. During the early years it was realised that the economic and technological facets of establishing a new industry were equally important and, in addition to fundamental research, strong emphasis was placed on the necessity of marketing this new technology. Although the initial emphasis was put on gamma sterilization, and today still forms the backbone of the radiation processing industry, the promising fields of polymer modification and food irradiation hold a lot of promise in the radiation processing industry. Following ten years of successfully introducing and providing a radiation service, the South African Atomic Energy Board in 1980 decided to transfer its service to the private sector. These developments in South Africa are a good sample of how a small country, through initial government envolvement, can acquire a sophisticated new private industry.

  1. Sensorial analysis evaluation in cereal bars preserved by ionizing radiation processing

    NASA Astrophysics Data System (ADS)

    Villavicencio, A. L. C. H.; Araújo, M. M.; Fanaro, G. B.; Rela, P. R.; Mancini-Filho, J.

    2007-11-01

    Gamma-rays utilized as a food-processing treatment to eliminate insect contamination is well established in food industries. Recent troubles in Brazilian cereal bars commercialization require a special consumer's attention because some products were contaminated by insects. To solve the problem, food-irradiation treatment was utilized as a safe and effective solution. The final product was free of insect contamination. The aim of this study was to determine the best radiation dose processing utilized to disinfestations and detect some change on sensorial characteristic by sensorial analysis in cereal bars. In this study, three different kinds of cereal bars were purchased in São Paulo (Brazil) in supermarkets and irradiated with 1.0, 2.0 and 3.0 kGy at "Instituto de Pesquisas Energéticas e Nucleares" (IPEN-CNEN/SP). The samples were treated with ionizing radiation using a 60Co gamma-ray facility (Gammacell 220, A.E.C.L.). That radiation doses were used successfully as an anti-insect treatment in the cereal bars, since in some food industries doses up to 3.0 kGy are used to guarantee at least a dose of 1.0 kGy in internal cereal bars package. Sensorial analysis was necessary since cereal bars contain ingredients very sensitive to ionizing radiation process.

  2. Increased radiation dose at mammography due to prolonged exposure, delayed processing, and increased film darkening

    SciTech Connect

    Kimme-Smith, C.; Bassett, L.W.; Gold, R.H.; Chow, S. )

    1991-02-01

    Four single-emulsion films introduced over the past 2 years--Du Pont Microvision, Fuji MiMa, Konica CM, and Eastman Kodak OM--were compared with Eastman Kodak OM SO-177 (Min-RE) film to evaluate their varying effects on mean glandular dose of reciprocity law failure due to prolonged exposure, delayed processing, and increased film darkening as a result of increased radiation exposure to improve penetration of glandular tissue. Exposures over 1.3 seconds led to increased radiation doses of 20%-30%. Delays in processing of 6 hours decreased processing speed by 11%-32% for all films except Du Pont Microvision. Optical density increases of 0.40 required 20%-30% more skin exposure for all five films. Optimal viewing densities were also evaluated and found to be different for each of the five films. Mammographers need to be aware of these differences in mammographic films to achieve maximum contrast at mammography.

  3. Advanced biochemical processes for geothermal brines: Annual operating plan, FY 1995

    SciTech Connect

    Premuzic, E.T.

    1995-02-01

    An R and D program to identify methods for the utilization and/or low cost of environmentally acceptable disposal of toxic geothermal residues has been established at the Brookhaven National Laboratory (BNL). Laboratory work has shown that a biochemical process developed at BNL, would meet regulatory costs and environmental requirements. In this work, microorganisms which can convert insoluble species of toxic metals, including radionuclides, into soluble species, have been identified. These organisms serve as models in the development of a biochemical process in which toxic metals present in geothermal residual sludges are converted into water soluble species. The produced solution can be reinjected or processed further to concentrate and recover commercially valuable metals. After the biochemical detoxification of geothermal residual sludges, the end-products are non-toxic and meet regulatory requirements. The overall process is a technically and environmentally acceptable cost-efficient process. It is anticipated that the new biotechnology will reduce the cost of surface disposal of sludges derived from geothermal brines by 25% or better.

  4. Modifications to population rate equations resulting from correlations between collisional and radiative processes

    NASA Technical Reports Server (NTRS)

    Ballagh, R. J.; Cooper, J.

    1984-01-01

    There are many systems of physical interest for which a set of rate equations for level populations can provide insight. If the system has two (or more) different mechanisms for effecting transition between levels, total rates of transfer are usually taken as the sum of rates that the individual mechanisms would cause acting alone. Using the example of a hydrogen atom subjected to (ionic and electronic) collisions and external radiation, it is shown that when these individual mechanisms overlap, the total transfer rates must be modified to account for correlations between collisional and radiative processes. For a broad-band radiation field the modified rates have a simple physical interpretation. In the case of a narrow-band field the overlapping events may cause new coherences to appear and interpretation of the modified 'rates' is more complicated.

  5. Linking microbial comunity composition and soil processes in acalifornia annual grassland and mixed-conifer forest

    SciTech Connect

    Balser, T.C.; Firestone, M.K.

    2003-07-21

    To investigate the potential role of microbial community composition in soil carbon and nitrogen cycling, we transplanted soil cores between a grassland and a conifer ecosystem in the Sierra Nevada California and measured soil process rates (N-mineralization, nitrous oxide and carbon dioxide flux, nitrification potential), soil water and temperature, and microbial community parameters (PLFA and substrate utilization profiles) over a 2 year period. Our goal was to assess whether microbial community composition could be related to soil process rates independent of soil temperature and water content. We performed multiple regression analyses using microbial community parameters and soil water and temperature as X-variables and soil process rates and inorganic N concentrations as Y-variables. We found that field soil temperature had the strongest relationship with CO2 production and soil NH4+ concentration, while microbial community characteristics correlated with N2O production, nitrification potential, gross N-mineralization, and soil NO3 concentration, independent of environmental controllers. We observed a relationship between specific components of the microbial community (as determined by PLFA) and soil processes, particularly processes tightly linked to microbial phylogeny (e.g. nitrification). The most apparent change in microbial community composition in response to the 2 year transplant was a change in relative abundance of fungi (there was only one significant change in PLFA biomarkers for bacteria during 2years). The relationship between microbial community composition and soil processes suggests that prediction of ecosystem response to environmental change may be improved by recognizing and accounting for changes in microbial community composition and physiological ecology.

  6. Proceedings of the Fourth Annual Workshop on the Use of Digital Computers in Process Control.

    ERIC Educational Resources Information Center

    Smith, Cecil L., Ed.

    Contents: Computer hardware testing (results of vendor-user interaction); CODIL (a new language for process control programing); the design and implementation of control systems utilizing CRT display consoles; the systems contractor - valuable professional or unnecessary middle man; power station digital computer applications; from inspiration to…

  7. Qualitative Information in Annual Reports & the Detection of Corporate Fraud: A Natural Language Processing Perspective

    ERIC Educational Resources Information Center

    Goel, Sunita

    2009-01-01

    High profile cases of fraudulent financial reporting such as those that occurred at Enron and WorldCom have shaken public confidence in the U.S. financial reporting process and have raised serious concerns about the roles of auditors, regulators, and analysts in financial reporting. In order to address these concerns and restore public confidence,…

  8. Optical studies of dynamical processes in disordered systems. [Annual] progress report

    SciTech Connect

    Yen, W.M.

    1993-12-31

    Focus continues to be on dynamical processes such as relaxation and energy diffusion which affect the structure and optical properties of disordered and amorphous materials, particularly glasses which are luminescent in the near infrared and their efficiency. Elementary excitations in amorphous materials are also under study. 12 refs.

  9. Ten Talks: Celebrating the Creative Process. Friends of the Library Annual Lecture Series, 1993-2002.

    ERIC Educational Resources Information Center

    Kenyon, Linda, Ed.

    Each spring, the Friends of the Library of the University of Waterloo Library invite the campus community to join in an event celebrating the creative process. The event reflects the day-to-day work of the library staff: bringing together information from a diverse range of disciplines for the purpose of creating new knowledge. This book includes…

  10. ANNUAL PROGRESS REPORT. INVESTIGATION OF PORE-SCALE PROCESSES THAT AFFECT SOIL VAPOR EXTRACTION

    EPA Science Inventory

    This research aims to determine the pore-scale processes that limit the removal of dense nonaqueous phase liquid (DNAPL) components in heterogeneous porous media during SVE. The specific objectives are to: 1) determine the effect of unswept zones on DNAPL removal during SVE, 2) d...

  11. Annual Report: Property Improvement in CZT via Modeling and Processing Innovations

    SciTech Connect

    Henager, Charles H.; Setyawan, Wahyu; Gao, Fei; Hu, Shenyang Y.; Bliss, Mary; Riley, Brian J.; Alvine, Kyle J.; Stave, Jean A.

    2013-09-01

    The objective of this project is to develop growth models of CZT crystals from the melt using vertical gradient freeze (VGF) or vertical Bridgman growth as a typical process. Further, the project will perform critical experiments including single crystal growth to validate the growth models and to provide detailed data for modeling and simulation. Ideally, the project will develop growth models that will provide, for the first time, choices for optimal CZT single crystal growth from the melt based on model input. The overarching goal that guides this research proposal is to produce large, single crystals of CZT with good yield and reproducible properties. In our view this depends on 1) understanding crystal growth processes, including annealing and cool-down processing, and 2) understanding the role of defects on detector response since it is not possible, yet, to produce defect-free materials. Models of defect structure and formation are addressed. Validated models and experiments on reducing defects in melt-grown crystals are used to guide our understanding of growth processes and in-furnace annealing plus cool-down.

  12. The interaction of radiative and dynamical processes during a simulated sudden stratospheric warming

    NASA Technical Reports Server (NTRS)

    Pierce, R. B.; Blackshear, W. T.; Fairlie, T. D.; Grose, W. L.; Turner, R. E.

    1993-01-01

    An analysis of a spontaneous sudden stratospheric warming that occurred during a 2-year integration of the Langley Research Center (LaRC) Atmospheric Simulation Model is presented. The simulated warming resembles observed 'wave 1' warmings in the Northern Hemisphere stratosphere and provides an opportunity to investigate the radiative and dynamical processes occurring during the warming event. Isentropic analysis of potential vorticity sources and sinks indicates that dynamically induced departures from radiative equilibrium play an important role in the warming event. Enhanced radiative cooling associated with a series of upper stratospheric warm pools leads to radiative dampening within the polar vortex. Within the 'surf zone' large-scale radiative cooling leads to diabatic advection of high potential vorticity air from aloft. Lagrangian area diagnostics of the simulated warming agree well with Limb Infrared Monitor of the Stratosphere (LIMS) analyses. Dynamical mixing is shown to account for the majority of the decrease in the size of the polar vortex during the simulated warming. An investigation of the nonlinear deformation of material lines that are initially coincident with diagnosed potential vorticity isopleths is conducted to clarify the relationship between the Lagrangian area diagnostics and potential vorticity advection during wave breaking events.

  13. Implication of observed cloud variability for parameterizations of microphysical and radiative transfer processes in climate models

    NASA Astrophysics Data System (ADS)

    Huang, D.; Liu, Y.

    2014-12-01

    The effects of subgrid cloud variability on grid-average microphysical rates and radiative fluxes are examined by use of long-term retrieval products at the Tropical West Pacific (TWP), Southern Great Plains (SGP), and North Slope of Alaska (NSA) sites of the Department of Energy's Atmospheric Radiation Measurement (ARM) Program. Four commonly used distribution functions, the truncated Gaussian, Gamma, lognormal, and Weibull distributions, are constrained to have the same mean and standard deviation as observed cloud liquid water content. The PDFs are then used to upscale relevant physical processes to obtain grid-average process rates. It is found that the truncated Gaussian representation results in up to 30% mean bias in autoconversion rate whereas the mean bias for the lognormal representation is about 10%. The Gamma and Weibull distribution function performs the best for the grid-average autoconversion rate with the mean relative bias less than 5%. For radiative fluxes, the lognormal and truncated Gaussian representations perform better than the Gamma and Weibull representations. The results show that the optimal choice of subgrid cloud distribution function depends on the nonlinearity of the process of interest and thus there is no single distribution function that works best for all parameterizations. Examination of the scale (window size) dependence of the mean bias indicates that the bias in grid-average process rates monotonically increases with increasing window sizes, suggesting the increasing importance of subgrid variability with increasing grid sizes.

  14. Cellulose based cationic adsorbent fabricated via radiation grafting process for treatment of dyes waste water.

    PubMed

    Goel, Narender Kumar; Kumar, Virendra; Misra, Nilanjal; Varshney, Lalit

    2015-11-01

    A cationized adsorbent was prepared from cellulosic cotton fabric waste via a single step-green-radiation grafting process using gamma radiation source, wherein poly[2-(methacryloyloxy) ethyl]trimethylammonium chloride (PMAETC) was covalently attached to cotton cellulose substrate. Radiation grafted (PMAETC-g-cellulose) adsorbent was investigated for removal of acid dyes from aqueous solutions using two model dyes: Acid Blue 25 (AB25) and Acid Blue 74 (AB74). The equilibrium adsorption data was analyzed by Langmuir and Freundlich isotherms, whereas kinetic data was analyzed by pseudo first order, pseudo second order, intra particle diffusion and Boyd's models. The PMAETC-g-cellulose adsorbent with 25% grafting yield exhibited equilibrium adsorption capacities of ∼ 540.0mg/g and ∼ 340.0mg/g for AB25 and AB74, respectively. Linear and nonlinear fitting of adsorption data suggested that the equilibrium adsorption process followed Langmuir adsorption isotherm model, whereas, the kinetic adsorption process followed pseudo-second order model. The multi-linearities observed in the intra-particle kinetic plots suggested that the intraparticle diffusion was not the only rate-controlling process in the adsorption of acid dyes on the adsorbent, which was further supported by Boyd's model. The adsorbent could be regenerated by eluting the adsorbed dye from the adsorbent and could be repeatedly used. PMID:26256369

  15. UNITED STATES DEPARTMENT OF ENERGY WASTE PROCESSING ANNUAL TECHNOLOGY DEVELOPMENT REPORT 2007

    SciTech Connect

    Bush, S

    2008-08-12

    The Office of Environmental Management's (EM) Roadmap, U.S. Department of Energy--Office of Environmental Management Engineering & Technology Roadmap (Roadmap), defines the Department's intent to reduce the technical risk and uncertainty in its cleanup programs. The unique nature of many of the remaining facilities will require a strong and responsive engineering and technology program to improve worker and public safety, and reduce costs and environmental impacts while completing the cleanup program. The technical risks and uncertainties associated with cleanup program were identified through: (1) project risk assessments, (2) programmatic external technical reviews and technology readiness assessments, and (3) direct site input. In order to address these needs, the technical risks and uncertainties were compiled and divided into the program areas of: Waste Processing, Groundwater and Soil Remediation, and Deactivation and Decommissioning (D&D). Strategic initiatives were then developed within each program area to address the technical risks and uncertainties in that program area. These strategic initiatives were subsequently incorporated into the Roadmap, where they form the strategic framework of the EM Engineering & Technology Program. The EM-21 Multi-Year Program Plan (MYPP) supports the goals and objectives of the Roadmap by providing direction for technology enhancement, development, and demonstrations that will lead to a reduction of technical uncertainties in EM waste processing activities. The current MYPP summarizes the strategic initiatives and the scope of the activities within each initiative that are proposed for the next five years (FY2008-2012) to improve safety and reduce costs and environmental impacts associated with waste processing; authorized budget levels will impact how much of the scope of activities can be executed, on a year-to-year basis. As a result of the importance of reducing technical risk and uncertainty in the EM Waste Processing

  16. Collisional processes of interest in MFE plasma research. Annual report, October 1, 1979-September 30, 1980

    SciTech Connect

    Olson, R. E.

    1980-09-24

    Research is divided into two general topics: (1) H/sup -/ formation collision processes and (2) the determination of scattering cross sections used to diagnose plasma properties. On topic (1) we investigated the effect on the H/sup +/ electron capture cross section when an alkali atom is optically pumped to its resonance state, the angular scattering in H/sup 0/ + Cs ..-->.. H/sup -/ + Cs/sup +/ collisions, and electron detachment processes in H/sup -/ and alkali and alkaline earth atom collisions. On topic (2) we completed work on the determination of the electron capture cross sections down to 10 eV for C/sup +5/, N/sup +5/, O/sup +6/ + H collisions and developed a model for the calculation of multi-ionization cross sections in energetic, highly charged ion-atom collisions.

  17. Investigation of test methods, material properties, and processes for solar cell encapsulants. Ninth annual report

    SciTech Connect

    Willis, P.B.

    1985-01-01

    Progress is reported in the areas of: aging and life prediction methodology and devices for solar cell encapsulation; the function of adhesion chemistry, primers, and a new diagnostic technique for estimations of bond durability; a study of fire retardant formulations for decreasing the potential flammability of solar modules; initial studies of the electrical insulating properties of encapsulation materials and measurement of the intrinsic dielectric strength; anti-soiling compounds for the prevention of soil build-up on the outer surface of the module; and low temperature processing encapsulants that permit module fabrication at temperatures less than 100/sup 0/C. Another area of study has been added to determine the degree to which formulation and processes affect the module quality and manufacturing yield.

  18. Solvent refined coal (SRC) process. Annual technical progress report, January 1979-December 1979

    SciTech Connect

    1980-11-01

    Part 3 consists of appendices 5, 6 and 7, which have been entered individually into EDB and ERA. They deal with regression analysis of pilot plant SRC-II yields to develop thermal response models of the process and the possibility of predicting yields from coal properties. The possibility of a runaway exothermal reaction under some operating conditions on the demonstration plant scale is also considered. (LTN)

  19. Investigation of test methods, material properties, and processes for solar cell encapsulants. Seventh annual report

    SciTech Connect

    Willis, P.B.

    1983-01-01

    The goal of the program is to identify and evaluate encapsulation materials and processes for the protection of silicon solar cells for service in a terrestrial environment. Aging and degradation studies were performed including: thermal aging, sunlamp exposures, aging in controlled environment reactors and outdoor photothermal aging devices, and metal catalyzed degradation. Other tests addressed water absorption, primers and adhesives, soiling experiments, and corrosion protection. (LEW)

  20. System of laser pump and synchrotron radiation probe microdiffraction to investigate optical recording process.

    PubMed

    Yasuda, Nobuhiro; Fukuyama, Yoshimitsu; Kimura, Shigeru; Ito, Kiminori; Tanaka, Yoshihito; Osawa, Hitoshi; Matsunaga, Toshiyuki; Kojima, Rie; Hisada, Kazuya; Tsuchino, Akio; Birukawa, Masahiro; Yamada, Noboru; Sekiguchi, Koji; Fujiie, Kazuhiko; Kawakubo, Osamu; Takata, Masaki

    2013-06-01

    We have developed a system of laser-pump and synchrotron radiation probe microdiffraction to investigate the phase-change process on a nanosecond time scale of Ge2Sb2Te5 film embedded in multi-layer structures, which corresponds to real optical recording media. The measurements were achieved by combining (i) the pump-laser system with a pulse width of 300 ps, (ii) a highly brilliant focused microbeam with wide peak-energy width (ΔE∕E ~ 2%) made by focusing helical undulator radiation without monochromatization, and (iii) a precise sample rotation stage to make repetitive measurements. We successfully detected a very weak time-resolved diffraction signal by using this system from 100-nm-thick Ge2Sb2Te5 phase-change layers. This enabled us to find the dependence of the crystal-amorphous phase change process of the Ge2Sb2Te5 layers on laser power. PMID:23822352

  1. The electron dose monitoring and control system in EB radiation processing for wires and cables

    NASA Astrophysics Data System (ADS)

    Zhou, Xinzhi; Zhou, Yong; Zhou, Youyi; Tang, Qiang

    2002-03-01

    This paper introduces a close-loop microcomputer control system used for EB radiation processing of wires and cables, which is based on the measurements and calculations of the absorbed dose distribution of 0.6-2.0 MeV electrons in circular compound materials. The calculation of electron energy deposition in 4-layer media is carried out by the bipartition model of electron transport. The design ideas, system configuration and implementation of this control system governed by a 586 personal computer under windows 98 OS are described in this paper. The field operation results such as control precision and step response curves of this system are also given. The control system has been used for EB radiation processing of wires.

  2. Potato peel extract-a natural antioxidant for retarding lipid peroxidation in radiation processed lamb meat.

    PubMed

    Kanatt, Sweetie R; Chander, Ramesh; Radhakrishna, P; Sharma, Arun

    2005-03-01

    The effective utilization of potato peel, a waste generated in large quantities by the food industry, as an antioxidant was investigated. Potato peel extract (PPE) exhibited high phenolic content (70.82 mg of catechin equivalent/100 g), chlorogenic acid (27.56 mg/100 g of sample) being the major component. The yield of total phenolics and chlorogenic acid increased by 26 and 60%, respectively, when the extract was prepared from gamma irradiated (150 Gy) potatoes. PPE showed excellent antioxidant activity as determined by beta-carotene bleaching and radical scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH). The suitability of PPE for controlling lipid oxidation of radiation processed lamb meat was also investigated. PPE (0.04%) when added to meat before radiation processing was found to retard lipid peroxidation of irradiated meat as measured by TBA number and carbonyl content. The antioxidant activity of PPE was found to be comparable to butylated hydroxytoluene (BHT). PMID:15740031

  3. Advanced biochemical processes for geothermal brines FY 1998 annual operating plan

    SciTech Connect

    1997-10-01

    As part of the overall Geothermal Energy Research which is aimed at the development of economical geothermal resources production systems, the aim of the Advanced Biochemical Processes for Geothermal Brines (ABPGB) effort is the development of economic and environmentally acceptable methods for disposal of geothermal wastes and conversion of by-products to useful forms. Methods are being developed for dissolution, separation and immobilization of geothermal wastes suitable for disposal, usable in inert construction materials, suitable for reinjection into the reservoir formation, or used for recovery of valuable metals.

  4. Annual Conference on Nuclear and Space Radiation Effects, 14th, College of William and Mary, Williamsburg, Va., July 12-15, 1977, Proceedings

    NASA Technical Reports Server (NTRS)

    Stahl, R. H.

    1977-01-01

    Topics related to processing and hardness assurance are considered, taking into account the radiation hardening of CMOS technologies, technological advances in the manufacture of radiation-hardened CMOS integrated circuits, CMOS hardness assurance through process controls and optimized design procedures, the application of operational amplifiers to hardened systems, a hard off-the-shelf SG1524 pulse width modulator, and the gamma-induced voltage breakdown anomaly in a Schottky diode. Basic mechanisms are examined, giving attention to chemical and structural aspects of the irradiation behavior of SiO2 films on silicon, experimental observations of the chemistry of the SiO2/Si interface, leakage current phenomena in irradiated SOS devices, the avalanche injection of holes into SiO2, the low-temperature radiation response of Al2O3 gate insulators, and neutron damage mechanisms in silicon at 10 K. Other subjects discussed are related to radiation effects in devices and circuits, space radiation effects, and aspects of simulation, energy deposition, and dosimetry.

  5. Radiative processes of UPSILON and UPSILON' and off-shell suppressions

    SciTech Connect

    Lahiri, A.; Bagchi, B.; Gautam, V.P.

    1980-09-01

    Within the framework of an extended vector-dominance scheme, the various radiative processes of UPSILON and UPSILON' are studied. The rates turn out to be generally much smaller than those of the corresponding psi decays and in some cases too small for direct observation. The off-shell UPSILON-..gamma.. and UPSILON'-..gamma.. coupling constants are found to be suppressed by about a couple of orders of magnitude compared with their on-shell values.

  6. A Coordinated Effort to Improve Parameterization of High-Latitude Cloud and Radiation Processes

    SciTech Connect

    J. O. Pinto, A.H. Lynch

    2005-12-14

    The goal of this project is the development and evaluation of improved parameterization of arctic cloud and radiation processes and implementation of the parameterizations into a climate model. Our research focuses specifically on the following issues: (1) continued development and evaluation of cloud microphysical parameterizations, focusing on issues of particular relevance for mixed phase clouds; and (2) evaluation of the mesoscale simulation of arctic cloud system life cycles.

  7. Section 7.1. new installations. Contribution of engineering to radiation processing

    NASA Astrophysics Data System (ADS)

    Keraron, Y.; Erhart, F.

    The favourable opinion of the Joint FAO/IAEA/WHO Expert Committee on the preservation of food by ionizing radiation has given rise to extensive developments throughout the world. SGN, an engineering company, in cooperation with research centres and the industry, took part to these recent efforts. The authors give examples of industrial programmes for the development of equipment and processes and review the results obtained.

  8. Annual performance appraisal: one organization's process and retrospective analysis of outcomes.

    PubMed

    Geddes, E Lynne; Gill, Caroline

    2012-01-01

    Performance assessment of personnel is an important component of an organization's quality management program, benefiting the organization, individuals and clients. Performance appraisal is the most common method. This article describes the three-part performance appraisal tool used at the authors' organization, a private inter-professional healthcare agency providing rehabilitation services to clients in the community, and presents the results of a retrospective analysis of the outcomes. Performance appraisals of 13 personnel were randomly selected, representing 39 chart audits and 25 joint client visits. The achievement of mandatory chart audit standards demonstrated 95 ± 7.2% compliance; expected standards showed 96 ± 3.3% compliance. Qualitative findings from the joint visits and interviews showed that therapists enjoyed the process and experience, valued the feedback and appreciated the support they received. Benefits and challenges of the process were identified, resulting in new initiatives being implemented. The authors confirmed that the tool achieves its intended purpose and is relevant in the home care setting. PMID:22354057

  9. The role of constitutive and inducible processes in the response of human squamous cell carcinoma cell lines to ionizing radiation

    SciTech Connect

    Schwartz, J.L.

    1993-06-01

    The inherent radiation sensitivity of the cells within a tumor is thought to contribute to the success or failure of radiation therapy. In vitro studies have shown that radiation sensitivity differences in squamous cell carcinoma cell lines reflect alterations in DNA repair. These alterations result from constitutive changes in chromosome organization, not radiation-inducible processes. While inducible responses may play some role in the radiation response of tumor cells, there is no evidence for their involvement in inherent tumor cell radiosensitivity differences or in the success or failure of radiotherapy for squamous cell carcinomas.

  10. Microphysics, Radiation and Surface Processes in the Goddard Cumulus Ensemble (GCE) Model

    NASA Technical Reports Server (NTRS)

    Tao, Wei-Kuo; Simpson, J.; Baker, D.; Braun, S.; Chou, M.-D.; Ferrier, B.; Johnson, D.; Khain, A.; Lang, S.; Lynn, B.

    2001-01-01

    The response of cloud systems to their environment is an important link in a chain of processes responsible for monsoons, frontal depression, El Nino Southern Oscillation (ENSO) episodes and other climate variations (e.g., 30-60 day intra-seasonal oscillations). Numerical models of cloud properties provide essential insights into the interactions of clouds with each other, with their surroundings, and with land and ocean surfaces. Significant advances are currently being made in the modeling of rainfall and rain-related cloud processes, ranging in scales from the very small up to the simulation of an extensive population of raining cumulus clouds in a tropical- or midlatitude-storm environment. The Goddard Cumulus Ensemble (GCE) model is a multi-dimensional nonhydrostatic dynamic/microphysical cloud resolving model. It has been used to simulate many different mesoscale convective systems that occurred in various geographic locations. In this paper, recent GCE model improvements (microphysics, radiation and surface processes) will be described as well as their impact on the development of precipitation events from various geographic locations. The performance of these new physical processes will be examined by comparing the model results with observations. In addition, the explicit interactive processes between cloud, radiation and surface processes will be discussed.

  11. Radiation

    NASA Video Gallery

    Outside the protective cocoon of Earth's atmosphere, the universe is full of harmful radiation. Astronauts who live and work in space are exposed not only to ultraviolet rays but also to space radi...

  12. Effect of radiation processing on nutritional, functional, sensory and antioxidant properties of red kidney beans

    NASA Astrophysics Data System (ADS)

    Marathe, S. A.; Deshpande, R.; Khamesra, Arohi; Ibrahim, Geeta; Jamdar, Sahayog N.

    2016-08-01

    In the present study dry red kidney beans (Phaseolus vulgaris), irradiated in the dose range of 0.25-10.0 kGy were evaluated for proximate composition, functional, sensory and antioxidant properties. Radiation processing up to 10 kGy did not affect proximate composition, hydration capacity and free fatty acid value. All the sensory attributes were unaffected at 1.0 kGy dose. The dose of 10 kGy, showed lower values for odor and taste, however, they were in acceptable range. Significant improvement in textural quality and reduction in cooking time was observed at dose of 10 kGy. Antioxidant activity of radiation processed samples was also assessed after normal processing such as soaking and pressure cooking. Both phenolic content and antioxidant activity evaluated in terms of DPPH free radical scavenging assay and inhibition in lipid peroxidation using rabbit erythrocyte ghost system, were marginally improved (5-10%) at the dose of 10 kGy in dry and cooked samples. During storage of samples for six months, no significant change was observed in sensory, cooking and antioxidant properties. Thus, radiation treatment of 1 kGy can be applied to get extended shelf life of kidney beans with improved functional properties without impairing bioactivity; nutritional quality and sensory property.

  13. LIGHT SOURCE: Physical design of a 10 MeV LINAC for polymer radiation processing

    NASA Astrophysics Data System (ADS)

    Feng, Guang-Yao; Pei, Yuan-Ji; Wang, Lin; Zhang, Shan-Cai; Wu, Cong-Feng; Jin, Kai; Li, Wei-Min

    2009-06-01

    In China, polymer radiation processing has become one of the most important processing industries. The radiation processing source may be an electron beam accelerator or a radioactive source. Physical design of an electron beam facility applied for radiation crosslinking is introduced in this paper because of it's much higher dose rate and efficiency. Main part of this facility is a 10 MeV travelling wave electron linac with constant impedance accelerating structure. A start to end simulation concerning the linac is reported in this paper. The codes Opera-3d, Poisson-superfish and Parmela are used to describe electromagnetic elements of the accelerator and track particle distribution from the cathode to the end of the linac. After beam dynamic optimization, wave phase velocities in the structure have been chosen to be 0.56, 0.9 and 0.999 respectively. Physical parameters about the main elements such as DC electron gun, iris-loaded periodic structure, solenoids, etc, are presented. Simulation results proves that it can satisfy the industrial requirement. The linac is under construction. Some components have been finished. Measurements proved that they are in a good agreement with the design values.

  14. Can the Fisher-Lande Process Account for Birds of Paradise and Other Sexual Radiations?

    PubMed

    Arnold, Stevan J; Houck, Lynne D

    2016-06-01

    Models of the Fisher-Lande process (FLP) have been used successfully to explore many aspects of evolution by sexual selection. Despite this success, quantitative tests of these models using data from sexual radiations are rare. Consequently, we do not know whether realistic versions of the FLP can account for the extent and the rate of evolution of sexually selected traits. To answer this question, we generalize the basic FLP model of sexual coevolution and compare predictions of that basic model with patterns observed in an iconic sexual radiation, birds of paradise. Our model tracks the coevolution of male and female traits (two in each sex) while relaxing some restrictive assumptions. Using computer simulations, we evaluate the behavior of the model and confirm that it is an Ornstein-Uhlenbeck (OU) process. We also assess the ability of the FLP to account for the quantitative aspects of ornament evolution in the genus Paradisaea using published measurements of display traits and a phylogeny of the genus. Finally, we use the program OUwie to compare model fits to generic OU and Brownian motion processes and to estimate FLP parameters. We show that to explain the sexual radiation of the genus Paradisaea one must either invoke extremely weak stabilizing selection on female mating preferences or allow the preference optimum to undergo Brownian motion at a modest rate. PMID:27172592

  15. Evaluation of phenolic compounds in maté ( Ilex paraguariensis) processed by gamma radiation

    NASA Astrophysics Data System (ADS)

    Furgeri, C.; Nunes, T. C. F.; Fanaro, G. B.; Souza, M. F. F.; Bastos, D. H. M.; Villavicencio, A. L. C. H.

    2009-07-01

    The radiation food processing has been demonstrating great effectiveness in the attack of pathogenic agents, while little compromising nutritional value and sensorial properties of foods. The maté ( Ilex paraguariensis), widely consumed product in South America, generally in the form of infusions with hot or cold water, calls of chimarrão or tererê, it is cited in literature as one of the best sources phenolic compounds. The antioxidants action of these constituent has been related to the protection of the organism against the free radicals, generated in alive, currently responsible for the sprouting of some degenerative illness as cancer, arteriosclerosis, rheumatic arthritis and cardiovascular clutters among others. The objective of that work was to evaluate the action of the processing for gamma radiation in phenolic compounds of tererê beverage in the doses of 0, 3, 5, 7 and 10 kGy. The observed results do not demonstrate significant alterations in phenolic compounds of tererê beverage processed by gamma radiation.

  16. Identification of Diurnal, Seasonal and Inter-Annual Variability Across SE Asian Field Observations of key Water Cycle Variables: Rainfall, net Radiation, Total Evaporation and River Discharge

    NASA Astrophysics Data System (ADS)

    Solera García, M. A.; Tych, W.; Chappell, N.

    2007-12-01

    The identification of periodic patterns in water cycle variables is critical to the understanding of land-atmosphere interactions, climate change and the evaluation of General Circulation Model (GCM) output. SE Asia in particular plays a very important role on the global climate because it is a large source of energy and water fluxes into the upper atmosphere. Cycle identification is carried out following the Data Based Mechanistic (DBM) philosophy, which focuses on the use of parsimonious, rigorous models which are characterised by lack of a priori assumptions, built in uncertainty analysis and final model acceptance dependent on the physical interpretation of the results. The DBM tool used here is the Unobserved Component - Dynamic Harmonic Regression (UC-DHR) model, which is a statistical method that allows the identification of variability in time series by introducing Time Variable Parameter (TVP) estimation of harmonic components. UC-DHR is not scale dependent and was thus applied to both hourly (to investigate diurnal variation) and fortnightly datasets (for intra- and inter-annual variability). The data used in the analysis has been gathered from existing catchment datasets for three regions of tropical SE Asia, namely Northern Thailand, Central Peninsular Malaysia and Northeast Borneo. These regions were chosen because they represent the hydro-climatic gradient (seasonal to equatorial) present within the tropics and because SE Asia has the most extensive set of catchment/plot studies within the humid tropics. Results show modeling tools were able to quantify the main patterns present in the observations throughout different time scales (diurnal, intra-annual and inter-annual) and the strength of the correlation pattern between the four hydro-climatic variables. The subsequent discussion focuses on the physical processes behind those patterns (e.g. diurnal variability caused by local convection due to solar heating; impact of El Niño Southern Oscillation

  17. Physical, radiative, and dynamical processes within a nighttime marine stratus cloud

    NASA Astrophysics Data System (ADS)

    Gultepe, Ismail

    1995-05-01

    Observations taken by aircraft and conventional platforms are used to investigate dynamical, physical, and radiative processes within a marine stratus cloud during the Canadian Atlantic Storms Program (CASP) II field project which took place over the east coast of Canada. Stratus which formed over the ocean on February 6, 1992 during the nighttime, is studied to analyze cloud top and base processes. The cloud was supercooled during the study period. Fluctuations and fluxes are calculated along constant flight altitude legs approximately 100 km long in space. The scales of structures larger than 5 km are removed from the analysis using a running average technique. Droplet spectra obtained by a forward scattering spectrometer probe (FSSP) were used in a 1-D radiative transfer model to calculate infrared (IR) fluxes and radiative heating rates. A heat conservation equation was used to estimate vertical air velocity ( w a ) within the cloud. The results showed that, because of a warmer ocean surface, significant moisture and heat were transferred from the ocean surface to the boundary layer. The cloud base was at about 400 m height and the top was at about 1.4 km. w a at the cloud base was estimated about 5 cm s-1. Strong IR cooling rate at the cloud top was calculated to be 75°C day-1 for a 100 m thick layer. Negative skewness in w a , suggesting narrow downdrafts, was likely due to radiative cooling at the cloud top. The entrainment velocity was found to be about 1.5 cm s-1 at cloud top. Mean moisture and heat fluxes within the cloud were estimated to be comparable to those from the ocean surface. Vertical air velocity at the cloud top due to radiative cooling was found to be about -40 cm s-1.

  18. Radon: Chemical and physical processes associated with its distribution. Annual progress report

    SciTech Connect

    Castleman, A.W. Jr.

    1992-12-01

    Assessing the mechanisms which govern the distribution, fate, and pathways of entry into biological systems, as well as the ultimate hazards associated with the radon progeny and their secondary reaction products, depends on knowledge of their chemistry. Our studies are directed toward developing fundamental information which will provide a basis for modeling studies that are requisite in obtaining a complete picture of growth, attachment to aerosols, and transport to the bioreceptor and ultimate incorporation within. Our program is divided into three major areas of research. These include measurement of the determination of their mobilities, study of the role of radon progeny ions in affecting reactions, including study of the influence of the degree of solvation (clustering), and examination of the important secondary reaction products, with particular attention to processes leading to chemical conversion of either the core ions or the ligands as a function of the degree of clustering.

  19. Solvent refined coal (SRC) process. Annual technical progress report, January 1979-December 1979

    SciTech Connect

    Not Available

    1980-11-01

    This report discusses the effects on SRC yields of seven process variables (reactor temperature, SRT, hydrogen partial pressure, recycle ash and coal concentrations, gas velocity and coal type) predicted by second-order regression models developed from a data base containing pilot plant data with both Kentucky and Powhatan coals. The only effect of coal type in the model is a shift in each yield by a constant factor. Although some differences were found between the models developed from the Kentucky data base (1) (which we call Kentucky models) and the pooled coal models, the general conclusions of the previous report are confirmed by the new models and the assumption of similar behavior of the two coals appears to be justified. In some respects the dependence of the yields (MAF coal basis) on variables such as pressure and temperature are clearer than in the previous models. The principal trends which emerge are discussed.

  20. Scale-up of miscible flood processes for heterogeneous reservoirs. Second annual report

    SciTech Connect

    Orr, F.M. Jr.

    1995-03-01

    Progress is reported for a comprehensive investigation of the scaling behavior of gas injection processes in heterogeneous reservoirs. The interplay of phase behavior, viscous fingering, gravity segregation, capillary imbibition and drainage, and reservoir heterogeneity is examined in a series of simulations and experiments. Use of streamtube to model multiphase flow is demonstrated to be a fast and accurate approach for displacements that are dominated by reservoir heterogeneity. The streamtube technique is particularly powerful for multiphase compositional displacements because it represents the effects of phase behavior with a one-dimensional flow and represents the effects of heterogeneity through the locations of streamtubes. A new approach for fast calculations of critical tie-lines directly from criticality conditions is reported. A global triangular structure solution for four-component flow systems, whose tie-lies meet at the edge of a quaternary phase diagram or lie in planes is presented. Also demonstrated is the extension of this solution to multicomponent systems under the same assumptions. The interplay of gravity, capillary and viscous forces on final residual oil saturation is examined experimentally and theoretically. The analysis of vertical equilibrium conditions for three-phase gravity drainage shows that almost all oil can be recovered from the top part of a reservoir. The prediction of spreading and stability of thin film is performed to investigate three-phase gravity drainage mechanisms. Finally, experimental results from gravity drainage of crude oil in the presence of CO{sub 2} suggest that gravity drainage could be an efficient oil recovery process for vertically fractured reservoirs.

  1. Perception of risk: proceedings of the XVth annual meeting of the National Council on Radiation Protection and Measurements

    SciTech Connect

    Goris, M.L.

    1981-03-01

    The book is a conglomerate of formal papers, discussions, and the textual minutes of a round table discussion with audience participation. The first part, and most interesting from my view-point, deals with the perception of risk or harm and societal attitudes. The second part contains papers that seem to be historical primers concerning radiobiology. This subject is surrounded by controversy, and it seems in part to be approached as an elephant would be by a tribe of blind zoologists. They poke and pinch, sometimes describe small parts in great detail, but never exactly circumscribe the object of the study. The purpose is to present a discussion of the harm due to radiation, specifically radiation from power sources. Closely related to this is the question of the regulatory agencies' role.

  2. Effects of simultaneous radiofrequency radiation and chemical exposure of mammalian cells. Volume 1. Annual report, 2 January-31 December 1984

    SciTech Connect

    Meltz, M.L.

    1987-08-01

    The major objective of this project was to determine whether radiofrequency radiation (RFR), at power densities and specific absorption rate (SAR) values which can result in temperature increases in the exposure medium, can affect the extent of chemically induced toxicity, mutagenicity, sister chromatid exchange, or chromosome aberrations in mammalian cells. The in-vitro system used for toxicity and mutagenicity studies is the mouse leukemic L5178Y cell thymidine kinase locus mutation assay.

  3. United States Transuranium and Uranium Registries: Researching radiation protection. USTUR annual report for February 1, 1999 through January 31, 2000

    SciTech Connect

    Ehrhart, Susan M.; Filipy, Ronald E.

    2000-07-01

    The United States Transuranium and Uranium Registries (USTUR) comprise a human tissue research program studying the deposition, biokinetics and dosimetry of the actinide elements in humans with the primary goals of providing data fundamental to the verification, refinement, or future development of radiation protection standards for these and other radionuclides, and of determining possible bioeffects on both a macro and subcellular level attributable to exposure to the actinides. This report covers USTUR activities during the year from February 1999 through January 2000.

  4. Multitarget tracking using optical processing. Annual report Jul 89-Aug 90

    SciTech Connect

    Casasent, D.

    1991-02-01

    Our work concerns multitarget tracking (MTT) for the Strategic Defense Initiative using optical processing. Our three layer system: detection, track initiation, and tracking was detailed in prior reports. Our present work involves a modified optical correlator and a new algorithm for detection, Hough transform extensions for track initiation, and new MTT data and algorithms. We now provide an overview of this work with details given in associated chapters. Chapter (2) provides new algorithm, architecture and simulation results on an AO system to optically achieve the key interpolation and subtraction functions required (1). SDI funds did not allow us to pursue this approach. The new track initiation work included extension of our optical Hough transform optical architecture to new algorithms to handle general curved and object tracks and general 3-D target trajectories using range data. The MTT algorithm and system concept received major attention. Work in this area included the optical laboratory demonstration of a 10-bit analog optical processor using a new architecture and algorithm, attention to the basic algorithmic question of whether a direct or iterative algorithm should be used with an optical processor for nonlinear matrix algorithms such as the extended Kalman filter.

  5. Investigation of test methods, material properties, and processes for solar cell encapsulants. Annual report

    SciTech Connect

    Willis, P. B.; Baum, B.; Schnitzer, H. S.

    1980-07-01

    The goal of this program is to identify, evaluate, and recommend encapsulant materials and processes for the production of cost-effective, long-life solar cell modules. Technical activities during the past year have covered a number of topics and have emphasized the development of solar module encapsulation technology that employs ethylene/vinyl acetate, copolymer (EVA) as the pottant. These activities have included: (1) continued production of encapsulation grade EVA in sheet form to meet the needs of the photovoltaic industry; (2) investigations of three non-blocking techniques for EVA sheet; (3) performed an economic analysis of the high volume production of each pottant in order to estimate the large volume selling price (EVA, EPDM, aliphatic urethane, PVC plastisol, and butyl acrylate); (4) initiated an experimental corrosion protection program to determine if metal components could be successfully protected by encapsulation; (5) began an investigation to determine the maximum temperature which can be tolerated by the candidate pottant material in the event of hot spot heating or other temperature override; (6) continuation of surveys of potentially useful outer cover materials; and (7) continued with the accelerated artificial weathering of candidate encapsulation materials. Study results are presented. (WHK)

  6. Effects of microbial processes on gas generation under expected WIPP repository conditions: Annual report through 1992

    SciTech Connect

    Francis, A.J.; Gillow, J.B.

    1993-09-01

    Microbial processes involved in gas generation from degradation of the organic constituents of transuranic waste under conditions expected at the Waste Isolation Pilot Plant (WIPP) repository are being investigated at Brookhaven National Laboratory. These laboratory studies are part of the Sandia National Laboratories -- WIPP Gas Generation Program. Gas generation due to microbial degradation of representative cellulosic waste was investigated in short-term (< 6 months) and long-term (> 6 months) experiments by incubating representative paper (filter paper, paper towels, and tissue) in WIPP brine under initially aerobic (air) and anaerobic (nitrogen) conditions. Samples from the WIPP surficial environment and underground workings harbor gas-producing halophilic microorganisms, the activities of which were studied in short-term experiments. The microorganisms metabolized a variety of organic compounds including cellulose under aerobic, anaerobic, and denitrifying conditions. In long-term experiments, the effects of added nutrients (trace amounts of ammonium nitrate, phosphate, and yeast extract), no nutrients, and nutrients plus excess nitrate on gas production from cellulose degradation.

  7. Process signatures in regional patterns of shoreline change on annual to decadal time scales

    NASA Astrophysics Data System (ADS)

    Lazarus, Eli D.; Murray, A. Brad

    2007-10-01

    Gradients in wave-driven alongshore sediment transport influence the morphologies of sediment-covered coastlines on a range of spatial and temporal scales, affecting accretion and erosion patterns relevant to human development. Recent theoretical findings predict that a correlation between shoreline change and shoreline curvature results from patterns of alongshore sediment flux; the sign (positive or negative) of that correlation depends on whether high- or low-angle waves dominated the wave climate. Using lidar surveys of the northern North Carolina coast from 1996-2005 to document shoreline change and quantify alongshore patterns of erosion and deposition, we isolate these signals diagnostic of alongshore-transport processes. Our analyses show a persistent, significant negative correlation between shoreline-position change and shoreline curvature consistent with a low-angle-dominated incident wave climate over the last decade. At large spatial scales, convex-seaward promontories have eroded landward, while concave-seaward bays have aggraded seaward, resulting in an apparent diffusion of alongshore morphological features.

  8. Cavitational hydrothermal oxidation: A new remediation process. Annual progress report, September 1996--August 1997

    SciTech Connect

    Suslick, K.S.

    1997-11-21

    'During the past year, the authors have continued to make substantial scientific progress on the understanding of cavitation phenomena in aqueous media and applications of cavitation to remediation processes. The efforts have focused on three separate areas: sonoluminescence as a probe of conditions created during cavitational collapse in aqueous media, the use of cavitation for remediation of contaminated water, and an addition of the use of ultrasound in the synthesis of novel heterogeneous catalysts for hydrodehalogenation of halocarbons under mild conditions. In order to gain further understanding of the conditions present during cavitation, the author has continued his studies of sonoluminescence. He has made recent breakthroughs in the use of emission spectroscopy for temperature and pressure measurement of cavitation events, which he expects to publish shortly. He has been able to measure for the first time the temperature of cavitation in water during multi-bubble cavitation in the presence of aromatic hydrocarbons. The emission from excited states of C{sub 2} in water gives temperatures that are consistent with adiabatic compressional heating, with maximum temperatures of 4,300 K. Prior measurements of cavitation temperatures in low vapor pressure nonaqueous media gave somewhat higher temperatures of 5,000 K. This work lays permanently to rest exotic mechanisms for cavitational chemistry, at least for cavitation fields.'

  9. Cavitational hydrothermal oxidation: A new remediation process. 1998 annual progress report

    SciTech Connect

    Suslick, K.S.

    1998-06-01

    'The primary goal is to develop a quantitative understanding of cavitation phenomena in aqueous media and the development of applications of cavitation to remediation processes. Efforts have focused on three separate areas: sonoluminescence as a probe of conditions created during cavitational collapse in aqueous media, the use of cavitation for remediation of contaminated water, and an addition of the use of ultrasound in the synthesis of novel heterogeneous catalysts for hydrodehalogenation of halocarbons under mild conditions. This report summarizes work after one year of a three year project. In order to gain further understanding of the conditions present during cavitation, the author has continued his studies of sonoluminescence. He has made recent breakthroughs in the use of emission spectroscopy for temperature and pressure measurement of cavitation events, which he expects to publish shortly. He has been able to measure for the first time the temperature of cavitation in water during multi-bubble cavitation in the presence of aromatic hydrocarbons. The emission from excited states of C{sub 2} in water gives temperatures that are consistent with adiabatic compressional heating, with maximum temperatures of 4,300 K. Prior measurements of cavitation temperatures in low vapor pressure nonaqueous media gave somewhat higher temperatures of 5,000 K. This work lays permanently to rest exotic mechanisms for cavitational chemistry, at least for cavitation fields.'

  10. Solvent refined coal (SRC) process. Annual technical progress report, January 1979-December 1979

    SciTech Connect

    Not Available

    1980-11-01

    A set of statistically designed experiments was used to study the effects of several important operating variables on coal liquefaction product yield structures. These studies used a Continuous Stirred-Tank Reactor to provide a hydrodynamically well-defined system from which kinetic data could be extracted. An analysis of the data shows that product yield structures can be adequately represented by a correlative model. It was shown that second-order effects (interaction and squared terms) are necessary to provide a good model fit of the data throughout the range studied. Three reports were issued covering the SRC-II database and yields as functions of operating variables. The results agree well with the generally-held concepts of the SRC reaction process, i.e., liquid phase hydrogenolysis of liquid coal which is time-dependent, thermally activated, catalyzed by recycle ash, and reaction rate-controlled. Four reports were issued summarizing the comprehensive SRC reactor thermal response models and reporting the results of several studies made with the models. Analytical equipment for measuring SRC off-gas composition and simulated distillation of coal liquids and appropriate procedures have been established.

  11. Scale-up of miscible flood processes for heterogeneous reservoirs. 1993 annual report

    SciTech Connect

    Orr, F.M. Jr.

    1994-05-01

    Progress is reported for a comprehensive investigation of the scaling behavior of gas injection processes in heterogeneous reservoirs. The interplay of phase behavior, viscous fingering, gravity segregation, capillary imbibition and drainage, and reservoir heterogeneity is examined in a series of simulations and experiments. Compositional and first-contact miscable simulations of viscous fingering and gravity segregation are compared to show that the two techniques can give very different results. Also, analyzed are two-dimensional and three-dimensional flows in which gravity segregation and viscous fingering interact. The simulations show that 2D and 3D flows can differ significantly. A comparison of analytical solutions for three-component two-phase flow with experimental results for oil/water/alcohol systems is reported. While the experiments and theory show reasonable agreement, some differences remain to be explained. The scaling behavior of the interaction of gravity segregation and capillary forces is investigated through simulations and through scaling arguments based on analysis of the differential equations. The simulations show that standard approaches do not agree well with results of low IFT displacements. The scaling analyses, however, reveal flow regimes where capillary, gravity, or viscous forces dominate the flow.

  12. Investigation of test methods, material properties, and processes for solar-cell encapsulants. Annual report

    SciTech Connect

    Willis, P. B.; Baum, B.

    1982-07-01

    Potentially useful low cost encapsulation materials are evaluated. The goal of the program is to identify, evaluate, test, and recommend encapsulant materials and processes for the production of cost-effective, long life solar cell modules. Technical investigations have concerned the development of advanced cure chemistries for lamination type pottants, the continued evaluation of soil resistant surface treatments, and the results of an accelerated aging test program for the comparison of material stabilities. Experiments are underway to assess the durability and cost effectiveness of coatings for protection of steel. Investigations are continuing with commercial maintenance coatings based on fluorocarbon and silicone-alkyd chemistries. Experiments were conducted to determine the effectiveness of occlusive coatings for wood products such as hard-board. An experimental program continued to determine the usefulness of soil resistant coatings. Primers were evaluated for effectiveness in bonding candidate pottants to outer covers, glass and substate materials. A program of accelerated aging and life predictive strategies is being conducted and data are reported for sunlamp exposure and thermal aging. Supporting activities are also discussed briefly. (LEW)

  13. Evaluation of microbial loads, physical characteristics, chemical constituents and biological properties of radiation processed Fagonia arabica

    NASA Astrophysics Data System (ADS)

    Khattak, Khanzadi Fatima

    2012-06-01

    Whole plant of Fagonia arabica with 3 different particle sizes (30, 50 and 70 mesh) were exposed to gamma radiation doses of 1-10 kGy from a Cobalt 60 source. A series of tests was performed in order to check the feasibility of irradiation processing of the plant. The applied radiation doses did not affect (P<0.05) pH and antimicrobial activities of the plant. The total weight of the dry extracts in methanol as well as water was found increased with irradiation. The irradiated samples showed significant increase in phenolic content and free radical scavenging activity using DPPH. Shortly after irradiation (on the day of radiation treatment) high amounts of free radicals were detected in the irradiated plant samples and the chemiluminescence measurements were generally found to be dose dependent. Maximum luminescence intensity was observed in case of samples with mesh size of 30 for all the radiation doses applied. After a period of one month the chemiluminescence signals of the irradiated samples approximated those of the controls. The study suggests that gamma irradiation treatment is effective for quality improvement and enhances certain beneficial biological properties of the treated materials.

  14. Investigation of microscopic radiation damage in waste forms using ODNMR and AEM techniques. 1997 annual progress report

    SciTech Connect

    Liu, G.

    1997-09-01

    'This project seeks to understand the microscopic effects of radiation damage in nuclear waste forms. The authors approach to this challenge encompasses studies in electron microscopy, laser spectroscopy, and computational modeling and simulation. During this first year of the project, efforts have focused on a-decay induced microscopic damage in crystalline orthophosphates (YPO{sub 4} and LuPO{sub 4}) that contain the short-lived a-emitting isotope {sup 244}Cm (t{sub 1/2} = 18.1 y). The samples that they studied were synthesized in 1980 and the initial {sup 244}Cm concentration was {approximately}1%. Studying these materials is of importance to nuclear waste management because of the opportunity to gain insight into accumulated radiation damage and the influence of aging on such damage. These factors are critical to the long-term performance of actual waste forms [1]. Lanthanide orthophosphates, including LuPO{sub 4} and YPO{sub 4}, have been suggested as waste forms for high level nuclear waste [2] and potential hosts for excess weapons plutonium [3,4]. The work is providing insight into the characteristics of these previously known radiation-resistant materials. They have observed loss of crystallinity (partial amorphization) as a direct consequence of prolonged exposure to intense alpha radiolysis in these materials. More importantly, the observation of microscopic cavities in these aged materials provides evidence of significant chemical decomposition that may be difficult to detect in the earlier stages of radiation damage. The preliminary results show that, in characterizing crystalline compounds as high level nuclear waste forms, chemical decomposition effects may be more important than lattice amorphization which has been the focus of many previous studies. More extensive studies, including in-situ analysis of the dynamics of thermal annealing of self-radiation induced amorphization and cavity formation, will be conducted on these aged {sup 244}Cm

  15. The role of IAEA in coordinating research and transferring technology in radiation chemistry and processing of polymers

    NASA Astrophysics Data System (ADS)

    Haji-Saeid, M.; Sampa, M. H.; Ramamoorthy, N.; Güven, O.; Chmielewski, A. G.

    2007-12-01

    The IAEA has been playing a significant role in fostering developments in radiation technology in general and radiation processing of polymers in particular, among its Member States (MS) and facilitate know-how/technology transfer to developing MS. The former is usually achieved through coordinated research projects (CRP) and thematic technical meetings, while the latter is mainly accomplished through technical cooperation (TC) projects. Coordinated research projects encourage research on, and development and practical application of, radiation technology to foster exchange of scientific and technical information. The technical cooperation (TC) programme helps Member States to realize their development priorities through the application of appropriate radiation technology. The IAEA has implemented several coordinated research projects (CRP) recently, including one on-going project, in the field of radiation processing of polymeric materials. The CRPs facilitated the acquisition and dissemination of know-how and technology for controlling of degradation effects in radiation processing of polymers, radiation synthesis of stimuli-responsive membranes, hydrogels and absorbents for separation purposes and the use of radiation processing to prepare biomaterials for applications in medicine. The IAEA extends cooperation to well-known international conferences dealing with radiation technology to facilitate participation of talented scientists from developing MS and building collaborations. The IAEA published technical documents, covering the findings of thematic technical meetings (TM) and coordinated research projects have been an important source of valuable practical information.

  16. Automated Thermal Image Processing for Detection and Classification of Birds and Bats - FY2012 Annual Report

    SciTech Connect

    Duberstein, Corey A.; Matzner, Shari; Cullinan, Valerie I.; Virden, Daniel J.; Myers, Joshua R.; Maxwell, Adam R.

    2012-09-01

    Surveying wildlife at risk from offshore wind energy development is difficult and expensive. Infrared video can be used to record birds and bats that pass through the camera view, but it is also time consuming and expensive to review video and determine what was recorded. We proposed to conduct algorithm and software development to identify and to differentiate thermally detected targets of interest that would allow automated processing of thermal image data to enumerate birds, bats, and insects. During FY2012 we developed computer code within MATLAB to identify objects recorded in video and extract attribute information that describes the objects recorded. We tested the efficiency of track identification using observer-based counts of tracks within segments of sample video. We examined object attributes, modeled the effects of random variability on attributes, and produced data smoothing techniques to limit random variation within attribute data. We also began drafting and testing methodology to identify objects recorded on video. We also recorded approximately 10 hours of infrared video of various marine birds, passerine birds, and bats near the Pacific Northwest National Laboratory (PNNL) Marine Sciences Laboratory (MSL) at Sequim, Washington. A total of 6 hours of bird video was captured overlooking Sequim Bay over a series of weeks. An additional 2 hours of video of birds was also captured during two weeks overlooking Dungeness Bay within the Strait of Juan de Fuca. Bats and passerine birds (swallows) were also recorded at dusk on the MSL campus during nine evenings. An observer noted the identity of objects viewed through the camera concurrently with recording. These video files will provide the information necessary to produce and test software developed during FY2013. The annotation will also form the basis for creation of a method to reliably identify recorded objects.

  17. Schools of Education in a New Era of Accountability: A Case Study of an Annual Report Process Used to Advance a Professional Learning Community

    ERIC Educational Resources Information Center

    Aceves, Manuel A.

    2013-01-01

    Institutions of higher education are entering a new era, one where cost, value, and quality are at the front of mind. To proactively ensure long-term viability, institutions must operate differently. This qualitative case study examined how the St. Alexander University School of Education's Annual Report Process impacted institutional…

  18. Constraints to the potential efficiency of converting solar radiation into phytoenergy in annual crops: from leaf biochemistry to canopy physiology and crop ecology.

    PubMed

    Yin, Xinyou; Struik, Paul C

    2015-11-01

    A new simple framework was proposed to quantify the efficiency of converting incoming solar radiation into phytoenergy in annual crops. It emphasizes the need to account for (i) efficiency gain when scaling up from the leaf level to the canopy level, and (ii) efficiency loss due to incomplete canopy closure during early and late phases of the crop cycle. Equations are given to estimate losses due to the constraints in various biochemical or physiological steps. For a given amount of daily radiation, a longer daytime was shown to increase energy use efficiency, because of the convex shape of the photosynthetic light response. Due to the higher cyclic electron transport, C4 leaves were found to have a lower energy loss via non-photochemical quenching, compared with C3 leaves. This contributes to the more linear light response in C4 than in C3 photosynthesis. Because of this difference in the curvature of the light response, canopy-to-leaf photosynthesis ratio, benefit from the optimum acclimation of the leaf nitrogen profile in the canopy, and productivity gain from future improvements in leaf photosynthetic parameters and canopy architecture were all shown to be higher in C3 than in C4 species. The indicative efficiency of converting incoming solar radiation into phytoenergy is ~2.2 and 3.0% in present C3 and C4 crops, respectively, when grown under well-managed conditions. An achievable efficiency via future genetic improvement was estimated to be as high as 3.6 and 4.1% for C3 and C4 crops, respectively. PMID:26224881

  19. Acid-base behavior in hydrothermal processing of wastes. 1997 annual progress report

    SciTech Connect

    1997-01-01

    'A major obstacle to the development of hydrothermal technology for treating DOE wastes has been a lack of scientific knowledge of solution chemistry, thermodynamics and transport phenomena. The progress over the last year is highlighted in the following four abstracts from manuscripts which have been submitted to journals. The authors also have made considerable progress on a spectroscopic study of the acid-base equilibria of Cr(VI). They have utilized novel spectroscopic indicators to study acid-base equilibria up to 380 C. Until now, very few systems have been studied at such high temperatures, although this information is vital for hydrothermal processing of wastes. The pH values of aqueous solutions of boric acid and KOH were measured with the optical indicator 2-naphthol at temperatures from 300 to 380 C. The equilibrium constant Kb-l for the reaction B(OH)3 + OH{sup -} = B(OH){sup -4} was determined from the pH measurements and correlated with a modified Born model. The titration curve for the addition of HCl to sodium borate exhibits strong acid-strong base behavior even at 350 C and 24.1 MPa. At these conditions, aqueous solutions of sodium borate buffer the pH at 9.6 t 0.25. submitted to Ind. Eng. Chem. Res. Acetic Acid and HCl Acid-base titrations for the KOH-acetic acid or NH{sub 3} -acetic acid systems were monitored with the optical indicator 2-naphthoic acid at 350 C and 34 MPa, and those for the HCl;Cl- system with acridine at 380 C and up to 34 MPa (5,000 psia ). KOH remains a much stronger base than NH,OH at high temperature. From 298 K to the critical temperature of water, the dissociation constant for HCl decreases by 13 orders of magnitude, and thus, the basicity of Cl{sup -} becomes significant. Consequently, the addition of NaCl to HCl raises the pH. The pH titration curves may be predicted with reasonable accuracy from the relevant equilibrium constants and Pitzer''s formulation of the Debye- Htickel equation for the activity coefficients.'

  20. Effects of microphysics and radiation on mesoscale processes of a midlatitude squall line

    SciTech Connect

    Chin, Hung-Neng Steve

    1994-04-01

    The understanding of the essential dynamics of mesoscale convective systems (MCSs) was well addressed in the literature. Effects of different physics on mesoscale processes of MCSs are, however, not well understood at some particular aspects, such as the origins of the rear inflow and the transition zone in the radar reflectivity. The objective of this research is focused on these two aspects for a midlatitude broken-line squall system. The existence of the rear inflow in MCSs has been identified in many observational and modeling studies. Although convincing evidence has shown that physical internal to the mesoscale system and pressure gradient effects in the convective and trailing stratiform regions are undoubtedly important in developing the rear inflow, it remains unclear bow these internal processes interact with pressure effects to trigger the rear inflow. Moreover, many modeling studies have replicated the bright melting ban, but the transition zone has not been successfully simulated. With the enhanced model physics, such as radiation, in a cloud model, we can simulate these features and provide some supplemental evidences, at least in part, to explain them. The modulation of the rear inflow by microphysics, long- (LW) and shortwave (SW) radiation, and its related cloud-radiative feedback to the modeled squall line system are also discussed in this study.

  1. Time-resolved GRB spectra in the complex radiation of synchrotron and Compton processes

    NASA Astrophysics Data System (ADS)

    Jiang, Y. G.; Hu, S. M.; Chen, X.; Li, K.; Guo, D. F.; Li, Y. T.; Li, H. Z.; Zhao, Y. Y.; Lin, H. N.; Chang, Z.

    2016-03-01

    Under the steady-state condition, the spectrum of electrons is investigated by solving the continuity equation under the complex radiation of both the synchrotron and Compton processes. The resulted gamma-ray burst (GRB) spectrum is a broken power law in both the fast and slow cooling phases. On the basis of this electron spectrum, the spectral indices of the Band function in four different phases are presented. In the complex radiation frame, the detail investigation on physical parameters reveals that three models can answer the α ˜ -1 problem, which are the synchrotron plus synchrotron self-Compton in the internal and the external shock models, and the synchrotron plus the external Compton processes in the external shock model. A possible marginal to fast cooling phase transition in GRB 080916C is discussed. The time-resolved spectra in different main pulses of GRB 100724B, GRB 100826A and GRB 130606B are investigated. We found that the flux is proportional to the peak energy in almost all main pulses. A significant (5σ) correlation for Fp ˜ Ep is evident the first main pulse of GRB 100826A, and three marginally significant (3σ) correlations Fp ˜ Ep are found in main pulses of GRB 100826A and GRB 130606B. The correlation between spectral index and Ep at 3 ˜ 4σ level are observed in the first main pulse of GRB 100826A. Such correlations are possible explained in the complex radiation scenario.

  2. Gamma radiation process for destruction of toxic polychlorinated biphenyls (Pcbs) in transformer oils.

    PubMed

    Singh, R K; Nayak, Poonam; Niyogi, U K; Khandal, R K; Singh, Gurdeep

    2006-01-01

    Polychlorinated biphenyls (PCBs) are synthetic organic chemicals commercially used worldwide in many applications. PCBs were used in oils because of their excellent properties such as good thermal stability, flame resistance, dielectric constant, high break down voltage, high boiling point and low volatility. However, because of their adverse affects on environment and human health, the use of PCBs has been banned now. PCBs are today considered among the widespread pollutants in the global system. PCBs sources still exist in various industrial products and in waste streams such as capacitor oils, lubricating oils, transformer oils, hydraulic oils, paints, rubbers, cables, etc. Several such materials containing PCBs emanating from various sources need to be detoxified before their reuse or before going to landfill for final disposal. Various remedial technologies have been developed in the world to destroy toxic PCBs. The radiolysis has been investigated as an environment-friendly process for waste oil treatment contaminated with PCBs, which may be a better alternative to the globally most widely accepted incineration method. A study was undertaken to detoxify PCBs in transformer oil by gamma radiation using Cobalt 60 source. Analysis of PCBs in transformer oils before and after radiation was carried out by GC-MS instrument. The effect of radiation dose and destruction of PCBs in transformer oils are discussed in details in the present paper. The method used was found to be highly effective and destruction was as high as 79 %. Further, the transformer oil samples were also evaluated before and after radiation to check their quality. The properties of oils were not significantly altered by gamma radiation treatment as evident from the results given in the paper. PMID:17913201

  3. Radiative Reverse Shock Laser Experiments Relevant to Accretion Processes in Cataclysmic Variables

    NASA Astrophysics Data System (ADS)

    Krauland, Christine

    2012-10-01

    We present results from experiments that explore radiative reverse shock waves and their contribution to the evolving dynamics of the cataclysmic variable (CV) system in which they reside. CVs are close binary star systems containing a white dwarf (WD) that accretes matter from its late-type main sequence companion star. In the process of accretion, a reverse shock forms when the supersonic infalling plasma is impeded. It provides the main source of radiation in the binary systems. In the case of a non-magnetic CV, the impact on an accretion disk produces this ``hot spot,'' where the flow obliquely strikes the rotating accretion disk. This collision region has many ambiguities as a radiation hydrodynamic system, but shock development in the infalling flow can be modeled [1]. We discuss the production of radiative reverse shocks in experiments at the Omega-60 laser facility. The ability of this high-intensity laser to create large energy densities in targets having millimeter-scale volumes makes it feasible to create supersonic plasma flows. Obtaining a radiative reverse shock in the laboratory requires a sufficiently fast flow (> 60 km/s) within a material whose opacity is large enough to produce energetically significant emission from experimentally achievable layers. We will show the radiographic and emission data from three campaigns on Omega-60 with accompanying CRASH [2] simulations, and will discuss the implications in the context of the CV system. [4pt] [1] Armitage, P. J. and Livio, M., ApJ, 493, 898 (1998).[0pt] [2] van der Holst, B., Toth, G., Sokolov, I.V., et al., ApJS, 194, 23 (2011).

  4. POTENTIAL AND FUTURE TRENDS ON INDUSTRIAL RADIATION PROCESSING TECHNOLOGY APPLICATION IN EMERGING COUNTRY - BRAZIL

    SciTech Connect

    Sampa, M.H.O.; Omi, N.M.; Rela, C.S.; Tsai, D.

    2004-10-06

    Brazil started the use of radiation technology in the seventies on crosslinking polyethylene for insulation of wire and electronic cables and sterilization of medical care devices. The present status of industrial applications of radiation shows that the use of this technology is increasing according to the economical development and the necessity to become the products manufactured in the local industries competitive in quality and price for internal and external market. The on going development activities in this area are concentrated on polymers processing (materials modification), foodstuff treatment and environmental protection. The development, the promotion and the technical support to consolidate this technology to the local industries is the main attribution of Institute for Energetic and Nuclear Research-IPEN, a governmental Institution.

  5. Kinetic cyclotron and synchrotron maser instabilities - Radio emission processes by direct amplification of radiation

    NASA Technical Reports Server (NTRS)

    Wu, C. S.

    1985-01-01

    This article reviews the theory of the kinetic (cyclotron and synchroton) mase instabilities. The subject has been extensively developed in recent years by many authors, who have been incited by the research of the auroral kilometric radiation and other applications. The maser mechanism is appealing because it is simple and efficient, and can lead to direct amplification of radiation. Two types of electron distribution functions have been investigated so far. These are the loss-cone and hollow-beam disributions which may exist pervasively in many regions within and beyond the solar system. It is likely that the maser instabilities can have many potentially important applications to numerous radio emission processes observed in astrophysical research.

  6. Recycling of the used automotive lubricating oil by ionizing radiation process

    NASA Astrophysics Data System (ADS)

    Scapin, M. A.; Duarte, C.; Sampa, M. H. O.; Sato, I. M.

    2007-11-01

    The recycling process of the used mineral oils has been gaining a very important gap in the context of environmental protection. Among mineral oils from petroleum, the lubricating oils are not entirely consumed during their use; therefore, it is necessary to apply a treatment for recuperation seeking their reuse. Moreover, the environmental legislation of countries does not allow their discard in any type of soils, rivers, lakes, oceans or sewerage systems. The conventional treatment has shown certain difficulties in the recuperation process for used oils. The ionizing radiation process is renowned in the industrial effluents treatments due to its high efficiency in the degradation of organic compounds and in the removal of metals by the action of OH rad , rad H and e aq radicals. In this work, used automotive lubricating oil was treated by the ionizing radiation process for metal removal and degradation of organic compounds. The samples were irradiated with 100 and 200 kGy irradiation doses. Determination of the elements Mg, Al, P, S, Cl, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Se, Mo, Nb, Cd, Sn, Ba, Bi and Pb, before and after the irradiation, was done by X-ray fluorescence technique and the organic profile was obtained by infrared spectroscopy.

  7. Pacific Northwest Laboratory annual report for 1990 to the DOE Office of Energy Research

    SciTech Connect

    Toburen, L.H.; Stults, B.R.; Mahaffey, J.A.

    1991-02-01

    Part four of the PNL Annual Report for 1990 includes research in physical sciences. Individual reports are processed separately for the data bases in the following areas: Dosimetry Research; Measurement Science; Radiological and Chemical Physics; Radiation Dosimetry; Radiation Biophysics; and Modelling Cellular Response to Genetic Damage. (FL)

  8. Structure, process and annual intensive care unit mortality across 69 centers: United States Critical Illness and Injury Trials Group Critical Illness Outcomes Study (USCIITG-CIOS)

    PubMed Central

    Checkley, William; Martin, Greg S; Brown, Samuel M; Chang, Steven Y; Dabbagh, Ousama; Fremont, Richard D; Girard, Timothy D; Rice, Todd W; Howell, Michael D; Johnson, Steven B; O'Brien, James; Park, Pauline K; Pastores, Stephen M; Patil, Namrata T; Pietropaoli, Anthony P; Putman, Maryann; Rotello, Leo; Siner, Jonathan; Sajid, Sahul; Murphy, David J; Sevransky, Jonathan E

    2014-01-01

    Objective Hospital-level variations in structure and process may affect clinical outcomes in intensive care units (ICUs). We sought to characterize the organizational structure, processes of care, use of protocols and standardized outcomes in a large sample of U.S. ICUs. Design We surveyed 69 ICUs about organization, size, volume, staffing, processes of care, use of protocols, and annual ICU mortality. Setting ICUs participating in the United States Critical Illness and Injury Trials Group Critical Illness Outcomes Study (USCIITG-CIOS). Measurements and Main Results We characterized structure and process variables across ICUs, investigated relationships between these variables and annual ICU mortality, and adjusted for illness severity using APACHE II. Ninety-four ICU directors were invited to participate in the study and 69 ICUs (73%) were enrolled, of which 25 (36%) were medical, 24 were surgical (35%) and 20 (29%) were of mixed type, and 64 (93%) were located in teaching hospitals with a median number of 5 trainees per ICU. Average annual ICU mortality was 10.8%, average APACHE II score was 19.3, 58% were closed units and 41% had a 24-hour in-house intensivist. In multivariable linear regression adjusted for APACHE II and multiple ICU structure and process factors, annual ICU mortality was lower in surgical ICUs than in medical ICUs (5.6% lower, 95% CI 2.4%–8.8%) or mixed ICUs (4.5% lower, 95% CI 0.4%–8.7%). We also found a lower annual ICU mortality among ICUs that had a daily plan of care review (5.8% lower, 95% CI 1.6%–10.0%) and a lower bed-to-nurse ratio (1.8% lower when the ratio decreased from 2:1 to 1.5:1; 95% CI 0.25%–3.4%). In contrast, 24-hour intensivist coverage (p=0.89) and closed ICU status (p=0.16) were not associated with a lower annual ICU mortality. Conclusions In a sample of 69 ICUs, a daily plan of care review and a lower bed-to-nurse ratio were both associated with a lower annual ICU mortality. In contrast to 24-hour intensivist

  9. REIONIZATION SIMULATIONS POWERED BY GRAPHICS PROCESSING UNITS. I. ON THE STRUCTURE OF THE ULTRAVIOLET RADIATION FIELD

    SciTech Connect

    Aubert, Dominique; Teyssier, Romain

    2010-11-20

    We present a set of cosmological simulations with radiative transfer in order to model the reionization history of the universe from z = 18 down to z = 6. Galaxy formation and the associated star formation are followed self-consistently with gas and dark matter dynamics using the RAMSES code, while radiative transfer is performed as a post-processing step using a moment-based method with the M1 closure relation in the ATON code. The latter has been ported to a multiple Graphics Processing Unit (GPU) architecture using the CUDA language together with the MPI library, resulting in an overall acceleration that allows us to tackle radiative transfer problems at a significantly higher resolution than previously reported: 1024{sup 3} + 2 levels of refinement for the hydrodynamic adaptive grid and 1024{sup 3} for the radiative transfer Cartesian grid. We reach a typical acceleration factor close to 100x when compared to the CPU version, allowing us to perform 1/4 million time steps in less than 3000 GPU hr. We observe good convergence properties between our different resolution runs for various volume- and mass-averaged quantities such as neutral fraction, UV background, and Thomson optical depth, as long as the effects of finite resolution on the star formation history are properly taken into account. We also show that the neutral fraction depends on the total mass density, in a way close to the predictions of photoionization equilibrium, as long as the effect of self-shielding are included in the background radiation model. Although our simulation suite has reached unprecedented mass and spatial resolution, we still fail in reproducing the z {approx} 6 constraints on the neutral fraction of hydrogen and the intensity of the UV background. In order to account for unresolved density fluctuations, we have modified our chemistry solver with a simple clumping factor model. Using our most spatially resolved simulation (12.5 Mpc h {sup -1} with 1024{sup 3} particles) to

  10. DOE 2012 occupational radiation exposure

    SciTech Connect

    none,

    2013-10-01

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2012 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. Over the past 5-year period, the occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site.

  11. DOE 2011 occupational radiation exposure

    SciTech Connect

    none,

    2012-12-01

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2011 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past five years.

  12. Radiation-dose estimates and hazard evaluations for inhaled airborne radionuclides. Annual progress report, July 1981-June 1982

    SciTech Connect

    Mewhinney, J.A.

    1983-06-01

    The objective was to conduct confirmatory research on aerosol characteristics and the resulting radiation dose distribution in animals following inhalation and to provide prediction of health consequences in humans due to airborne radioactivity which might be released in normal operations or under accident conditions during production of nuclear fuel composed of mixed oxides of U and Pu. Four research reports summarize the results of specific areas of research. The first paper details development of a method for determination of specific surface area of small samples of mixed oxide or pure PuO/sub 2/ particles. The second paper details the extension of the biomathematical model previously used to describe retention, distribution and excretion of Pu from these mixed oxide aerosols to include a description of Am and U components of these aerosols. The third paper summarizes the biological responses observed in radiation dose pattern studies in which dogs, monkeys and rate received inhalation exposures to either 750/sup 0/C heat treated UO/sub 2/ + PuO/sub 2/, 1750/sup 0/C heat-treated (U,Pu)O/sub 2/ or 850/sup 0/C heat-treated pure PuO/sub 2/. The fourth paper described dose-response studies in which rats were exposed to (U,Pu)O/sub 2/ or pure PuO/sub 2/. This paper updates earlier reports and summarizes the status of animals through approximately 650 days after inhalation.

  13. PREFACE: Selected papers from the Fourth Annual q-bio Conference on Cellular Information Processing Selected papers from the Fourth Annual q-bio Conference on Cellular Information Processing

    NASA Astrophysics Data System (ADS)

    Nemenman, Ilya; Faeder, James R.; Hlavacek, William S.; Jiang, Yi; Wall, Michael E.; Zilman, Anton

    2011-10-01

    Summary This special issue consists of 11 original papers that elaborate on work presented at the Fourth Annual q-bio Conference on Cellular Information Processing, which was held on the campus of St John's College in Santa Fe, New Mexico, USA, 11-14 August 2010. Now in its fourth year, the q-bio conference has changed considerably over time. It is now well established and a major event in systems biology. The 2010 conference saw attendees from all continents (except Antarctica!) sharing novel results and participating in lively discussions at both the oral and poster sessions. The conference was oversubscribed and grew to 27 contributed talks, 16 poster spotlights and 137 contributed posters. We deliberately decreased the number of invited speakers to 21 to leave more space for contributed presentations, and the attendee feedback confirmed that the choice was a success. Although the q-bio conference has grown and matured, it has remained true to the original goal of being an intimate and dynamic event that brings together modeling, theory and quantitative experimentation for the study of cell regulation and information processing. Funded in part by a grant from NIGMS and by DOE funds through the Los Alamos National Laboratory Directed Research and Development program, the conference has continued to exhibit youth and vigor by attracting (and partially supporting) over 100 undergraduate, graduate and postdoctoral researchers. The associated q-bio summer school, which precedes the conference each year, further emphasizes the development of junior scientists and makes q-bio a singular event in its impact on the future of quantitative biology. In addition to an increased international presence, the conference has notably diversified its demographic representation within the USA, including increased participation from the southeastern corner of the country. One big change in the conference this year is our new publication partner, Physical Biology. Although we are very

  14. Coupling of a vacuum-ultraviolet-radiation source to a processing system

    SciTech Connect

    Chatterton, J. D.; Upadhyaya, G. S.; Shohet, J. L.; Lauer, J. L.; Bathke, R. D.; Kukkady, K.

    2006-08-15

    A hollow capillary array is examined as a coupling window between an electron cyclotron resonance plasma vacuum ultraviolet (vuv) source and a separate processing chamber. The transmission of vuv through the capillary array as a function of wavelength is measured and shown to agree with theoretical calculations. A silicon wafer with a dielectric surface is then placed in the processing chamber and exposed to vuv, both with and without the capillary array. A Kelvin probe is used to measure the surface charge induced on the wafer by photoemission in both cases, which confirms the previously measured transmission values. The results show that a capillary array can efficiently couple vuv radiation from a source to a processing chamber without significant modification in the spectrum and its resulting effects on a material.

  15. The radiation-induced fibroatrophic process: therapeutic perspective via the antioxidant pathway.

    PubMed

    Delanian, Sylvie; Lefaix, Jean-Louis

    2004-11-01

    The radiation-induced fibroatrophic process (RIF) constitutes a late, local and unavoidable sequela to high-dose radiotherapy, traditionally considered irreversible. Today, this process is partly reversible, thanks to recent progress in understanding the physiopathology of the lesions it causes and the results of recent clinical trials using antioxidant therapy. This review includes a synthetic description of the static and dynamic features of the RIF process, as reflected by its clinical, instrumental and histopathological characteristics, and by its cellular and molecular regulation. Schematically, three successive clinical and histopathological phases can be distinguished: a pre-fibrotic aspecific inflammatory phase, a constitutive fibrotic cellular phase, and a matrix densification and remodelling phase, possibly ending in terminal tissular necrosis. The respective roles of the chief actors in the RIF process are defined, as well as their development with time. A fibroblastic stromal hypothesis is suggested revolving around a 'gravitational effect' exerted by the couple ROS (reactive oxygen species)--fibroblasts, and partly mediated by TGF-beta1. A variety of strategies have been tested for the management of RIF. In the light of the mechanisms described, a curative procedure has been proposed via the antioxidant pathway. In particular, it was showed that superoxide dismutase and combined pentoxifylline-tocopherol treatment enables the process of established radiation-induced fibroatrophy to be greatly reduced or even reversed, both in clinical practice and animal experiments. The efficacy of combined pentoxifylline-tocopherol treatment in superficial RIF was confirmed in a randomised clinical trial, and then in successful phase II trials especially in uterine fibroatrophy and osteoradionecrosis. It is of critical importance to evaluate these new management approaches in larger clinical trials and to improve the recording of results for better outcome analysis

  16. Post-processing of 3D-printed parts using femtosecond and picosecond laser radiation

    NASA Astrophysics Data System (ADS)

    Mingareev, Ilya; Gehlich, Nils; Bonhoff, Tobias; Meiners, Wilhelm; Kelbassa, Ingomar; Biermann, Tim; Richardson, Martin C.

    2014-03-01

    Additive manufacturing, also known as 3D-printing, is a near-net shape manufacturing approach, delivering part geometry that can be considerably affected by various process conditions, heat-induced distortions, solidified melt droplets, partially fused powders, and surface modifications induced by the manufacturing tool motion and processing strategy. High-repetition rate femtosecond and picosecond laser radiation was utilized to improve surface quality of metal parts manufactured by laser additive techniques. Different laser scanning approaches were utilized to increase the ablation efficiency and to reduce the surface roughness while preserving the initial part geometry. We studied post-processing of 3D-shaped parts made of Nickel- and Titanium-base alloys by utilizing Selective Laser Melting (SLM) and Laser Metal Deposition (LMD) as additive manufacturing techniques. Process parameters such as the pulse energy, the number of layers and their spatial separation were varied. Surface processing in several layers was necessary to remove the excessive material, such as individual powder particles, and to reduce the average surface roughness from asdeposited 22-45 μm to a few microns. Due to the ultrafast laser-processing regime and the small heat-affected zone induced in materials, this novel integrated manufacturing approach can be used to post-process parts made of thermally and mechanically sensitive materials, and to attain complex designed shapes with micrometer precision.

  17. Development of X-ray tracer diagnostics for radiatively-driven ablator experiments [annual report FY1998

    SciTech Connect

    J.J. MacFarlane; D.H. Cohen; P. Wang; G.A. Moses; R.R. Peterson; P.A. Jaanimagi; O.L. Langen; R.E. Olson; T.J. Murphy; G.R. Magelssen; N.D. Delamater

    1999-05-01

    This report covers fiscal year 1998 of our ongoing project to develop tracer X-ray spectroscopic diagnostics for hohlraum environments. This effort focused on an experimental campaign carried out at OMEGA on 25--27 August 1998. This phase of the project heavily emphasized experimental design, diagnostic development, and target fabrication, as well as building up numerical models for the experiments. The spectral diagnostic under development involves using two thin (few 1000 {angstrom}) mid-Z tracers in two witness plates mounted on the side of a hohlraum with the tracers' K{sub a} absorption features seen against an X-ray backlighter. The absorption data are used to sample the time-dependent, localized properties of each witness plate as a radiation wave ablates it. The experiments represented the first application of this diagnostic, in this case to side-by-side doped and undoped plastic to investigate the effects of capsule ablator dopants.

  18. Committee on Interagency Radiation Research and Policy Coordination (CIRRPC). Sixth annual report, July 1, 1989--June 30, 1990

    SciTech Connect

    Young, A.L.

    1990-06-30

    Three CIRRPC efforts were brought to completion this last year. One of this year`s highlights was the publication of the BEIR V report cited above. This report provides a comprehensive review of up-to- date risk estimations to be used in assessing potential health effects from exposure to ionizing radiation. Also completed for publication during this period was CIRRPC Science Panel Report No. 7, Planning for Human Health Effects Research in the Event of a Nuclear Accident. Efforts of the Subpanel addressing the policy implications and use of the National Institutes of Health Radioepidemiological Tables were terminated following the Subpanel`s unanimous conclusion that further effort to develop a consensus report was unnecessary because the scientific limitations upon the uses of the Tables had already been correctly described in several publications, and there were no indications of any significant instances of the Tables being misused.

  19. Microphysics, Radiation and Surface Processes in the Goddard Cumulus Ensemble (GCE) Model

    NASA Technical Reports Server (NTRS)

    Tao, Wei-Kuo; Starr, David (Technical Monitor)

    2002-01-01

    One of the most promising methods to test the representation of cloud processes used in climate models is to use observations together with Cloud Resolving Models (CRMs). The CRMs use more sophisticated and realistic representations of cloud microphysical processes, and they can reasonably well resolve the time evolution, structure, and life cycles of clouds and cloud systems (size about 2-200 km). The CRMs also allow explicit interaction between out-going longwave (cooling) and in-coming solar (heating) radiation with clouds. Observations can provide the initial conditions and validation for CRM results. The Goddard Cumulus Ensemble (GCE) Model, a CRM, has been developed and improved at NASA/Goddard Space Flight Center over the past two decades. The GCE model has been used to understand the following: 1) water and energy cycles and their roles in the tropical climate system; 2) the vertical redistribution of ozone and trace constituents by individual clouds and well organized convective systems over various spatial scales; 3) the relationship between the vertical distribution of latent heating (phase change of water) and the large-scale (pre-storm) environment; 4) the validity of assumptions used in the representation of cloud processes in climate and global circulation models; and 5) the representation of cloud microphysical processes and their interaction with radiative forcing over tropical and midlatitude regions. Four-dimensional cloud and latent heating fields simulated from the GCE model have been provided to the TRMM Science Data and Information System (TSDIS) to develop and improve algorithms for retrieving rainfall and latent heating rates for TRMM and the NASA Earth Observing System (EOS). More than 90 referred papers using the GCE model have been published in the last two decades. Also, more than 10 national and international universities are currently using the GCE model for research and teaching. In this talk, five specific major GCE improvements: (1

  20. Radiation-induced leukemia: Comparative studies in mouse and man. Annual performance report, June 1, 1991--October 31, 1991

    SciTech Connect

    Haas, M.

    1991-12-31

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

  1. DOE occupational radiation exposure 2007 report

    SciTech Connect

    none,

    2007-12-31

    The U.S. Department of Energy (DOE) Office of Corporate Safety Analysis (HS-30) within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE.* The annual DOEOccupational Radiation Exposure 2007 Report provides an evaluation of DOE-wide performance regarding compliance with DOE Part 835 dose limits and ALARA process requirements. In addition the report provides data to DOE organizations responsible for developing policies for protection of individuals from the effects of radiation. This report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past five years.

  2. Processing summary report: Fabrication of cesium and strontium heat and radiation sources

    SciTech Connect

    Holton, L.K. Jr.; Surma, J.E.; Allen, R.P.; Brouns, R.A.; Bryan, G.H.; Elliott, M.L.; Goles, R.W.; Haun, F.E.; Klein, R.F.; Peters, R.D.

    1989-02-01

    The Pacific Northwest Laboratory (PNL), has produced 30 isotopic heat sources (canisters) for the Federal Republic of Germany (FRG) to be used as part of a repository testing program in the Asse Salt Mine. PNL program work involved the filling, closure, and decontamination of the 30 canisters. The canisters were fabricated (filled) in three separate processing campaigns using the radioactive liquid-fed ceramic melter to produce a borosilicate glass. Within the borosilicate glass matrix radiochemical constituents (/sup 137/Cs and /sup 90/Sr) were immobilized to yield a product with a predetermined decay heat and surface radiation exposure rate.

  3. Hawking radiation screening and Penrose process shielding in the Kerr black hole

    NASA Astrophysics Data System (ADS)

    Mc Caughey, Eamon

    2016-04-01

    The radial motion of massive particles in the equatorial plane of a Kerr black hole is considered. Screening of the Hawking radiation and shielding of the Penrose process are examined (both inside and outside the ergosphere) and their effect on the evaporation of the black hole is studied. In particular, the locus and width of a classically forbidden region and their dependence on the particle's angular momentum and energy is analysed. Tunneling of particles between the boundaries of this region is considered and the transmission coefficient determined.

  4. Primary photophysical processes which define the biological and therapeutic effect of low-intensity laser radiation

    NASA Astrophysics Data System (ADS)

    Mostovnikov, Vasili A.; Mostovnikova, Galina R.; Plavski, Vitali Y.; Plavskaja, Ljudmila G.; Morozova, Raisa P.

    1995-01-01

    It is shown that reversible conformations (changes of spatial structure) of the cell components, responsible for the metabolic processes regulation, are the basis of biological activity and as a consequence therapeutic effect of low-intensity laser radiation. The physical mechanism of these changes is the reorientation of high regulated anisotropic parts-domains with the liquid- crystalline type of ordering due to the interaction between electric field of the laser lightwave and integral electric dipole of the domain (light induced analogue of Frederix's effect).

  5. Radiative neutron captures by neutron-rich nuclei and the r-process nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Goriely, S.

    1998-09-01

    The radiative neutron capture by neutron-rich nuclei is estimated with an improved description of the electric giant dipole resonance. In addition, 3 major effects affecting the capture rates by exotic neutron-rich nuclei are studied. These concern the existence of a low-energy E1 pygmy resonance, the overestimate of the statistical predictions for resonance-deficient nuclei and the direct capture mechanism. The total (n,γ) reaction rates including these 3 effects are evaluated for 3100 neutron-rich nuclei and used in parametric r-process calculations to analyze their impact on the r-abundance distribution.

  6. GEMGrid: a wafer post-processed GEM-like radiation detector

    NASA Astrophysics Data System (ADS)

    Blanco Carballo, V. M.; Bilevych, Y.; Chefdeville, M.; Fransen, M.; van der Graaf, H.; Salm, C.; Schmitz, J.; Timmermans, J.

    2009-09-01

    This paper presents a new wafer post-processed micropatterned gaseous radiation detector called GEMGrid. The device consists of a GEM-like structure fabricated with SU-8 photoresist directly on top of a Timepix chip with zero gap distance. The detector characteristics have been studied in several gas mixtures. The device is capable of tracking minimum ionizing particles and exhibits good energy resolution on 55Fe decays. We further show a strongly improved mechanical robustness of these GEM-like structures as compared to a pillar-supported integrated Micromegas.

  7. Observation of hydrodynamic processes of radiation-ablated plasma in a small hole

    SciTech Connect

    Li, Hang; Kuang, Longyu; Jiang, Shaoen Ding, Yongkun; Song, Tianming; Yang, Jiamin Zhu, Tuo; Lin, Zhiwei; Zheng, Jianhua; Zhang, Haiying; Yu, Ruizhen; Liu, Shenye; Hu, Guangyue; Zhao, Bin; Zheng, Jian

    2015-07-15

    In the hohlraum used in laser indirect-drive inertial confinement fusion experiments, hydrodynamic processes of radiation-ablated high-Z plasma have a great effect on laser injection efficiency, radiation uniformity, and diagnosis of hohlraum radiation field from diagnostic windows (DW). To study plasma filling in the DWs, a laser-irradiated Ti disk was used to generate 2–5 keV narrow energy band X-ray as the intense backlighter source, and laser-produced X-ray in a hohlraum with low-Z foam tamper was used to heat a small hole surrounded by gold wall with 150 μm in diameter and 100 μm deep. The hydrodynamic movement of the gold plasma in the small hole was measured by an X-ray framing camera and the results are analyzed. Quantitative measurement of the plasma areal density distribution and evolution in the small hole can be used to assess the effect of plasma filling on the diagnosis from the DWs.

  8. On-site installation and shielding of a mobile electron accelerator for radiation processing

    NASA Astrophysics Data System (ADS)

    Catana, Dumitru; Panaitescu, Julian; Axinescu, Silviu; Manolache, Dumitru; Matei, Constantin; Corcodel, Calin; Ulmeanu, Magdalena; Bestea, Virgil

    1995-05-01

    The development of radiation processing of some bulk products, e.g. grains or potatoes, would be sustained if the irradiation had been carried out at the place of storage, i.e. silo. A promising solution is proposed consisting of a mobile electron accelerator, installed on a couple of trucks and traveling from one customer to another. The energy of the accelerated electrons was chosen at 5 MeV, with 10 to 50 kW beam power. The irradiation is possible either with electrons or with bremsstrahlung. A major problem of the above solution is the provision of adequate shielding at the customer, with a minimum investment cost. Plans for a bunker are presented, which houses the truck carrying the radiation head. The beam is vertical downwards, through the truck floor, through a transport pipe and a scanning horn. The irradiation takes place in a pit, where the products are transported through a belt. The belt path is so chosen as to minimize openings in the shielding. Shielding calculations are presented supposing a working regime with 5 MeV bremsstrahlung. Leakage and scattered radiation are taken into account.

  9. Energy loss process analysis for radiation degradation and immediate recovery of amorphous silicon alloy solar cells

    NASA Astrophysics Data System (ADS)

    Sato, Shin-ichiro; Beernink, Kevin; Ohshima, Takeshi

    2015-06-01

    Performance degradation of a-Si/a-SiGe/a-SiGe triple-junction solar cells due to irradiation of silicon ions, electrons, and protons are investigated using an in-situ current-voltage measurement system. The performance recovery immediately after irradiation is also investigated. Significant recovery is always observed independent of radiation species and temperature. It is shown that the characteristic time, which is obtained by analyzing the short-circuit current annealing behavior, is an important parameter for practical applications in space. In addition, the radiation degradation mechanism is discussed by analyzing the energy loss process of incident particles (ionizing energy loss: IEL, and non-ionizing energy loss: NIEL) and their relative damage factors. It is determined that ionizing dose is the primarily parameter for electron degradation whereas displacement damage dose is the primarily parameter for proton degradation. This is because the ratio of NIEL to IEL in the case of electrons is small enough to be ignored the damage due to NIEL although the defect creation ratio of NIEL is much larger than that of IEL in the cases of both protons and electrons. The impact of “radiation quality effect” has to be considered to understand the degradation due to Si ion irradiation.

  10. Broadband Outdoor Radiometer Calibration Process for the Atmospheric Radiation Measurement Program

    SciTech Connect

    Dooraghi, Michael

    2015-09-01

    The Atmospheric Radiation Measurement program (ARM) maintains a fleet of monitoring stations to aid in the improved scientific understanding of the basic physics related to radiative feedback processes in the atmosphere, particularly the interactions among clouds and aerosols. ARM obtains continuous measurements and conducts field campaigns to provide data products that aid in the improvement and further development of climate models. All of the measurement campaigns include a suite of solar measurements. The Solar Radiation Research Laboratory at the National Renewable Energy Laboratory supports ARM's full suite of stations in a number of ways, including troubleshooting issues that arise as part of the data-quality reviews; managing engineering changes to the standard setup; and providing calibration services and assistance to the full fleet of solar-related instruments, including pyranometers, pyrgeometers, pyrheliometers, as well as the temperature/relative humidity probes, multimeters, and data acquisition systems that are used in the calibrations performed at the Southern Great Plains Radiometer Calibration Facility. This paper discusses all aspects related to the support provided to the calibration of the instruments in the solar monitoring fleet.

  11. Evaluating Contextual Processing in Diffusion MRI: Application to Optic Radiation Reconstruction for Epilepsy Surgery

    PubMed Central

    Tax, Chantal M. W.; Duits, Remco; Vilanova, Anna; ter Haar Romeny, Bart M.; Hofman, Paul; Wagner, Louis; Leemans, Alexander; Ossenblok, Pauly

    2014-01-01

    Diffusion MRI and tractography allow for investigation of the architectural configuration of white matter in vivo, offering new avenues for applications like presurgical planning. Despite the promising outlook, there are many pitfalls that complicate its use for (clinical) application. Amongst these are inaccuracies in the geometry of the diffusion profiles on which tractography is based, and poor alignment with neighboring profiles. Recently developed contextual processing techniques, including enhancement and well-posed geometric sharpening, have shown to result in sharper and better aligned diffusion profiles. However, the research that has been conducted up to now is mainly of theoretical nature, and so far these techniques have only been evaluated by visual inspection of the diffusion profiles. In this work, the method is evaluated in a clinically relevant application: the reconstruction of the optic radiation for epilepsy surgery. For this evaluation we have developed a framework in which we incorporate a novel scoring procedure for individual pathways. We demonstrate that, using enhancement and sharpening, the extraction of an anatomically plausible reconstruction of the optic radiation from a large amount of probabilistic pathways is greatly improved in three healthy controls, where currently used methods fail to do so. Furthermore, challenging reconstructions of the optic radiation in three epilepsy surgery candidates with extensive brain lesions demonstrate that it is beneficial to integrate these methods in surgical planning. PMID:25077946

  12. Observation of hydrodynamic processes of radiation-ablated plasma in a small hole

    NASA Astrophysics Data System (ADS)

    Li, Hang; Song, Tianming; Yang, Jiamin; Zhu, Tuo; Lin, Zhiwei; Zheng, Jianhua; Kuang, Longyu; Zhang, Haiying; Yu, Ruizhen; Liu, Shenye; Jiang, Shaoen; Ding, Yongkun; Hu, Guangyue; Zhao, Bin; Zheng, Jian

    2015-07-01

    In the hohlraum used in laser indirect-drive inertial confinement fusion experiments, hydrodynamic processes of radiation-ablated high-Z plasma have a great effect on laser injection efficiency, radiation uniformity, and diagnosis of hohlraum radiation field from diagnostic windows (DW). To study plasma filling in the DWs, a laser-irradiated Ti disk was used to generate 2-5 keV narrow energy band X-ray as the intense backlighter source, and laser-produced X-ray in a hohlraum with low-Z foam tamper was used to heat a small hole surrounded by gold wall with 150 μm in diameter and 100 μm deep. The hydrodynamic movement of the gold plasma in the small hole was measured by an X-ray framing camera and the results are analyzed. Quantitative measurement of the plasma areal density distribution and evolution in the small hole can be used to assess the effect of plasma filling on the diagnosis from the DWs.

  13. Thin layer imaging process for microlithography using radiation at strongly attenuated wavelengths

    DOEpatents

    Wheeler, David R.

    2004-01-06

    A method for patterning of resist surfaces which is particularly advantageous for systems having low photon flux and highly energetic, strongly attenuated radiation. A thin imaging layer is created with uniform silicon distribution in a bilayer format. An image is formed by exposing selected regions of the silylated imaging layer to radiation. The radiation incident upon the silyliated resist material results in acid generation which either catalyzes cleavage of Si--O bonds to produce moieties that are volatile enough to be driven off in a post exposure bake step or produces a resist material where the exposed portions of the imaging layer are soluble in a basic solution, thereby desilylating the exposed areas of the imaging layer. The process is self limiting due to the limited quantity of silyl groups within each region of the pattern. Following the post exposure bake step, an etching step, generally an oxygen plasma etch, removes the resist material from the de-silylated areas of the imaging layer.

  14. Computer Modeling of Solar Ion Radiation Processing of Planetary Surface Materials

    NASA Astrophysics Data System (ADS)

    Chamberlin, Sydney; Christoffersen, Roy

    2007-10-01

    Airless bodies in the interstellar environment are constantly bombarded with ions from stellar winds. Resulting ion-atom interactions gradually cause chemical and structural changes to occur on their surfaces. One of the more significant changes is the formation of amorphous rims on regolith grains. Ion transport physics gives some description of the dynamics underlying such radiation damage, but gives little insight into other factors such as the width of the damaged layer and the degree of amorphization over time. Monte Carlo simulation programs for modeling ion-atom interactions exist, but have never been fully exploited for use in space radiation processing and fail to accommodate the range of parameters present in plasmas such as the solar wind. In this study we have utilized an existing Monte Carlo program, Transport and Range of Ions in Matter (TRIM), to model radiation in the space environment. A series of input data files and calculation protocols were created to investigate a range of typical solar wind parameters. The new outputs of the model consist of damage profiles for the amount of deposited ion collision energy as a function of ion angle, solar wind energy distribution, and sputtering rate. Results obtained with this model are found to be in reasonable agreement with experimental measured results from irradiated mineral grains.

  15. Study of Photoionization Processes of 3d Transition Metal Compound CoCl2 Using Synchrotron Radiation

    SciTech Connect

    Goerguelueer, Oe.; Tutay, A.; Al-Hada, M.; Richter, T.; Zimmermann, P.; Martins, M.

    2007-04-23

    In this work, the photoionization processes of 3d transition metal compound CoCl2 have been investigated using monochromatized synchrotron radiation of the storage ring BESSY II and the atomic-molecular beam technique.

  16. Aerosol-radiation-cloud and precipitation processes during dust events (Invited)

    NASA Astrophysics Data System (ADS)

    Kallos, G. B.; Solomos, S.; Kushta, J.; Mitsakou, C.; Athanasiadis, P.; Spyrou, C.; Tremback, C.

    2010-12-01

    In places like the Mediterranean region where anthropogenic aerosols coexist with desert dust the aerosol-radiation-cloud processes are rather complicated. The mixture of different age of air pollutants of anthropogenic origin with Saharan dust and sea salt may lead to the formation of other particles with different characteristics. The mixture of the aerosols and gases from anthropogenic and natural origin (desert dust and sea salt) results in the formation of new types of PM with different physico-chemical properties and especially hygroscopicity (e.g. inside clouds or within the marine boundary layer) through heterogeneous processes. The new particle formation has different characteristics and therefore they have different impacts on cloud formation and precipitation. In an attempt to better understand links and feedbacks between air pollution and climate the new Integrated Community Limited Area Modeling System - ICLAMS has been developed. ICLAMS is an enhanced version of RAMS.v6 modeling system. It includes sub-models for the dust and sea salt cycles, gas and aqueous phase chemistry, gas to particle conversion and heterogeneous chemistry processes. All these processes are directly coupled with meteorology. RAMS has an explicit cloud microphysical scheme with eight categories of hydrometeors. The cloud droplets spectrum is explicitly calculated from model meteorology and prognostic CCN and IN properties (total number concentration, size distribution properties and chemical composition). Sulphate coated dust particles are efficient CCN because of their increased hygroscopicity while uncoated dust particles are efficient IN. The photochemical processes are directly linked to the RAMS radiative transfer scheme, which in the new model is RRTM. Absorption of short wave solar radiation from airborne dust leads to heating of the dust layer which can also affect the cloud processes. Mid and low tropospheric warming by dust is one of the new features that the model can

  17. How gamma radiation processing systems are benefiting from the latest advances in information technology

    NASA Astrophysics Data System (ADS)

    Gibson, Wayne H.; Levesque, Daniel

    2000-03-01

    This paper discusses how gamma irradiation plants are putting the latest advances in computer and information technology to use for better process control, cost savings, and strategic advantages. Some irradiator operations are gaining significant benefits by integrating computer technology and robotics with real-time information processing, multi-user databases, and communication networks. The paper reports on several irradiation facilities that are making good use of client/server LANs, user-friendly graphics interfaces, supervisory control and data acquisition (SCADA) systems, distributed I/O with real-time sensor devices, trending analysis, real-time product tracking, dynamic product scheduling, and automated dosimetry reading. These plants are lowering costs by fast and reliable reconciliation of dosimetry data, easier validation to GMP requirements, optimizing production flow, and faster release of sterilized products to market. There is a trend in the manufacturing sector towards total automation using "predictive process control". Real-time verification of process parameters "on-the-run" allows control parameters to be adjusted appropriately, before the process strays out of limits. Applying this technology to the gamma radiation process, control will be based on monitoring the key parameters such as time, and making adjustments during the process to optimize quality and throughput. Dosimetry results will be used as a quality control measurement rather than as a final monitor for the release of the product. Results are correlated with the irradiation process data to quickly and confidently reconcile variations. Ultimately, a parametric process control system utilizing responsive control, feedback and verification will not only increase productivity and process efficiency, but can also result in operating within tighter dose control set points.

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

    SciTech Connect

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

    2009-11-12

    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.

  19. Current status and prospects of radiation processing studies in Taiwan, R. O. C.

    NASA Astrophysics Data System (ADS)

    Fu, Ying-Kai

    The research on radiation processing in past 5 years in Taiwan covers industrial application of radiation-induced polymerization and curing, medical application of radiosterilization of medical supplies, chemicals, and amniotic membrane for wound dressing as well as agricultural application of food irradiation and genogenesis etc. Radiation-induced polymerization applied on wood and bamboo plastic composite of methyl methacrylate, radiation curing on polyurethane and silicon rubber for biomedical material using to separate oxygen from nitrogen and on crosslinking of pp and ps for artificial skin for wound dressing were all success. Radio-sterilization of disposable medical supplies appears for immediate application after the studies of the dose requirement of several radioresistant microorganisms, dose distribution measured by chemical dosimeters of ceric sulfate and Fricke dosimeter as well as quality control system were completed. The radiosterilization study of tetracycline - HCl and few detoxic agents like atropine sulfate and toxogonin has shown the promising results on radiosterilization of chemicals, the radiosterilization of amniotic membrane for wound dressing are also success. Food irradiation on sprouting inhibition of potatoes, garlic etc, on radiodisinfestation of cereal insects, tobacco bettles, soybean insects, and flour beetles, as well as on frog legs and porks have been also discussed. The legislation on radiosterilization of medical supplies and food irradiation of 14 items has been approved by National Health Administration, R.O.C. in July of 1982 and January of 1985 respectively. Even 24 hrs-operation of 1 Mega curie irradiation plant at INER can not satisfy the requirement of radiosterilization of medical supplies. A private commercial irradiation plant is urgently needed in Taiwan other than at INER now.

  20. Genetic engineering of a radiation-resistant bacterium for biodegradation of ixed wastes. 1998 annual progress report

    SciTech Connect

    Lidstrom, M.E.

    1998-06-01

    'Because of their tolerance to very high levels of ionizing radiation, members of the genus Deinococcus have received considerable attention over the past years. The type species of the genus, Deinococcus radiodurans, has been studied extensively in several labs. Although researchers are only beginning to understand the mechanisms by which this Gram-positive bacterium is able to repair massive DNA damage after radiation dosages as high as 5 Mrad, it has become evident that its recombination machinery has several unique characteristics (1--4). The aim of the present studies is to engineer D. radiodurans into a detoxifier for bioremediation of complex waste mixtures, containing heavy metals, halo-organics and radionuclides, making use of its ability to be biologically active in environments where they will be exposed to high levels of radiation. For that purpose, the authors aim to clone and express several broad spectrum oxygenases and heavy metal resistance determinants, and test survival and activities of these strains in artificial mixtures of contaminants, designed to simulate DOE mixed waste streams. This report summarizes work after 0.5 year of a 3-year project. The initial studies have focused on the development of an insertional expression system for D. radiodurans R1. This effort has involved two parts, namely: (1) promoter analysis, and (2) development of insertion systems. Several studies have shown that the expression signals used by D. radiodurans differ considerably from those found in other bacteria. Although D. radiodurans contains a typical eubacterial RNA polymerase core enzyme (based on TBLASTN searches on the genome sequence), Escherichia coli promoters are not recognized in D. radiodurans and vice versa (5). To expand the basic understanding of the requirements for transcription, and to optimize expression of (heterologous) genes, they will follow two strategies. First, a promoter-probe vector is being developed for the selection of promoter

  1. Modeling photosynthesis of discontinuous plant canopies by linking the Geometric Optical Radiative Transfer model with biochemical processes

    NASA Astrophysics Data System (ADS)

    Xin, Q.; Gong, P.; Li, W.

    2015-06-01

    Modeling vegetation photosynthesis is essential for understanding carbon exchanges between terrestrial ecosystems and the atmosphere. The radiative transfer process within plant canopies is one of the key drivers that regulate canopy photosynthesis. Most vegetation cover consists of discrete plant crowns, of which the physical observation departs from the underlying assumption of a homogenous and uniform medium in classic radiative transfer theory. Here we advance the Geometric Optical Radiative Transfer (GORT) model to simulate photosynthesis activities for discontinuous plant canopies. We separate radiation absorption into two components that are absorbed by sunlit and shaded leaves, and derive analytical solutions by integrating over the canopy layer. To model leaf-level and canopy-level photosynthesis, leaf light absorption is then linked to the biochemical process of gas diffusion through leaf stomata. The canopy gap probability derived from GORT differs from classic radiative transfer theory, especially when the leaf area index is high, due to leaf clumping effects. Tree characteristics such as tree density, crown shape, and canopy length affect leaf clumping and regulate radiation interception. Modeled gross primary production (GPP) for two deciduous forest stands could explain more than 80% of the variance of flux tower measurements at both near hourly and daily timescales. We demonstrate that ambient CO2 concentrations influence daytime vegetation photosynthesis, which needs to be considered in biogeochemical models. The proposed model is complementary to classic radiative transfer theory and shows promise in modeling the radiative transfer process and photosynthetic activities over discontinuous forest canopies.

  2. Nature of oxygen containing radicals in radiation chemistry and photochemistry of aqueous solutions. Annual progress report, September 1979-July 1980

    SciTech Connect

    Czapski, G.

    1980-01-01

    During this year, emphasis will be given on the properties of HO/sub 2/ and O/sub 2//sup -/ and OH, mainly in their role in biological systems. We will continue to study and elucidate how O/sub 2//sup -/ reacts in biological systems. The toxicity of O/sub 2//sup -/ is quite well established but the mechanism is still obscure. One way O/sub 2//sup -/ is toxic is that OH is formed from O/sub 2//sup -/ through reduction of Fe/sup 3 +/, and subsequently the reaction of Fe/sup 2 +/ with H/sub 2/O/sub 2/ (Fenton reaction). This mechanism is sometimes called the Haber Weiss Reaction. We will study if reduction of Fe/sup 3 +/ complexes by O/sub 2//sup -/ in biological systems does catalyze the Haber Weiss reaction and if OH is formed in this mechanism. The role of oxygen, radiosensitizers in radiation damage of bacteriophages and cells will be further studied, as well as on E. coli and enzymes. Use of different mutants, such as ones with repair deficiencies, or others which are deficient in glutathione will help to elucidate the role of O/sub 2//sup -/ and O/sub 2/ toxicity. We will try to elucidate the formation and role of OH, O/sub 2//sup -/ and O/sub 2/ in these systems as well as the relative contribution of endogenous and exogenous damage, and the role of direct and indirect radiation damage to cells. As there is some doubt how and if SOD protects cells from irradiation as literature results show lots of conflict, we will try to clear this point, in studies with E. coli mutants, and adding SOD endogenously and exogenously. We also intend to study if SOD (super oxide dismutase) does react only with O/sub 2//sup -/ or also with biological peroxides (RO/sub 2/) and hydroperoxides (RO/sub 2/H). Further studies of O/sub 2//sup -/ and O/sub 2/ with various cytochromes, and hemoglobins is planned.

  3. Radiation effects on materials in the near-field of a nuclear waste repository. 1997 annual progress report

    SciTech Connect

    Wang, L.M.; Ewing, R.C.

    1997-11-25

    'Sheet silicates (e.g. micas and clays) are important constituents of a wide variety of geological formations such as granite, basalt, and sandstone. Sheet silicates, particularly clays such as bentonite are common materials in near-field engineered barriers in high-level nuclear waste (HLW) repositories. This is because migration of radionuclides from an underground HLW repository to the geosphere may be significantly reduced by sorption of radionuclides (e.g., Pu, U and Np) onto sheet silicates (e.g., clays and micas) that line the fractures and pores of the rocks along groundwater flowpaths. In addition to surface sorption, it has been suggested that some sheet silicates may also be able to incorporate many radionuclides, such as Cs and Sr, in the inter-layer sites of the sheet structure. However, theability of the sheet silicates to incorporate radionuclides and retard release and migration of radionuclides may be significantly affected by the near-field radiation due to the decay of fission products and actinides. for example, the unique properties of the sheet structures will be lost completely if the structure becomes amorphous due to irradiation effects. Thus, the study of irradiation effects on sheet-structures, such as structural damage and modification of chemical properties, are critical to the performance assessment of long-term repository behavior.'

  4. Improved radiation dosimetry/risk estimates to facilitate environmental management of plutonium contaminated sites. 1998 annual progress report

    SciTech Connect

    Scott, B.R.

    1998-06-01

    'The objective of this research is to evaluate distributions of possible alpha radiation doses to the lung, bone, and liver and associated health-risk distributions for plutonium (Pu) inhalation-exposure scenarios relevant to environmental management of PuO{sub 2}-contaminated sites. Currently available dosimetry/risk models do not apply to exposure scenarios where, at most, a small number of highly radioactive PuO{sub 2} particles are inhaled (stochastic exposure [SE] paradigm). For the SE paradigm, risk distributions are more relevant than point estimates of risk. The focus of the research is on the SE paradigm and on high specific activity, alpha-emitting (HSA-aE) particles such as 238 PuO{sub 2} . The scientific goal is to develop a stochastic respiratory tract dosimetry/risk computer model for evaluating the desired absorbed dose distributions and associated health-risk distributions, for Department of Energy (DOE) workers and members of the public. This report summarizes results after 1 year of a 2-year project.'

  5. Quality profile of litchi ( Litchi chinensis) cultivars from India and effect of radiation processing

    NASA Astrophysics Data System (ADS)

    Hajare, Sachin N.; Saxena, Sudhanshu; Kumar, Sanjeev; Wadhawan, Surbhi; More, Varsha; Mishra, B. B.; Narayan Parte, Madan; Gautam, Satyendra; Sharma, Arun

    2010-09-01

    Litchi ( Litchi chinensis) is a non-climacteric tropical fruit. The fruit has a short shelf-life making its marketing difficult. Physical, biochemical, microbiological, and organoleptic properties of two major commercially grown Indian cultivars of litchi, 'Shahi' and 'China' were studied. The effect of gamma radiation processing and low temperature storage on the above parameters was evaluated to standardize the optimal process parameters for shelf-life extension of litchi. Physical and biochemical parameters analyzed included weight, moisture, pH, titratable acidity, texture, color, total and reducing sugar, total soluble solids, vitamin C, and flavonoid content. Weight, moisture content, and pH in the fresh fruit ranged between 21-26 g, 74-77%, and 3.7-4.4, respectively, whereas, total and reducing sugar ranged 10-15, and 10-13 g%, respectively. In 'Shahi' vitamin C content was found to be around 17-19 mg%, whereas, in 'China' it was 22-28 mg%. Flavonoid content was in the range of 26-34 μg catechin equivalents/g of fresh fruit. Total surface and internal bacterial load was around 4 and 3 log cfu/g, respectively. Surface yeast-mold count (YMC) was ˜3 log cfu/g whereas internal YMC was ˜2 log cfu/g. Radiation treatment reduced microbial load in a dose dependent manner. Treatment at 0.5 kGy did not significantly affect the quality parameters of the fruit. Treated fruits retained the "good" organoleptic rating during storage. Thus, radiation treatment (0.5 kGy) in combination with low temperature (4 °C) storage achieved a shelf-life of 28 days for litchi fruit.

  6. Evaluation of radiation resistance of the bacterial contaminants from femoral heads processed for allogeneic transplantation

    NASA Astrophysics Data System (ADS)

    Singh, Rita; Singh, Durgeshwer

    2009-09-01

    Femoral heads excised during surgery were obtained from patients who had a fractured neck of the femur and were processed as bone allograft. The bacterial contaminants were isolated from femoral heads at different stages of processing and identified based on morphological characteristics and biochemical tests. Bacterial contaminants on bone were mainly Gram-positive bacilli and cocci (58.3%). Twenty-four isolates from bone samples were screened for resistance to radiation. The D10 values for Gram-negative bacteria isolated from femoral heads ranged from 0.17 to 0.65 kGy. Higher D10 values 0.56-1.04 kGy were observed for Gram-positive bacterial isolates.

  7. Radiation dose reduction in digital radiography using wavelet-based image processing methods

    NASA Astrophysics Data System (ADS)

    Watanabe, Haruyuki; Tsai, Du-Yih; Lee, Yongbum; Matsuyama, Eri; Kojima, Katsuyuki

    2011-03-01

    In this paper, we investigate the effect of the use of wavelet transform for image processing on radiation dose reduction in computed radiography (CR), by measuring various physical characteristics of the wavelet-transformed images. Moreover, we propose a wavelet-based method for offering a possibility to reduce radiation dose while maintaining a clinically acceptable image quality. The proposed method integrates the advantages of a previously proposed technique, i.e., sigmoid-type transfer curve for wavelet coefficient weighting adjustment technique, as well as a wavelet soft-thresholding technique. The former can improve contrast and spatial resolution of CR images, the latter is able to improve the performance of image noise. In the investigation of physical characteristics, modulation transfer function, noise power spectrum, and contrast-to-noise ratio of CR images processed by the proposed method and other different methods were measured and compared. Furthermore, visual evaluation was performed using Scheffe's pair comparison method. Experimental results showed that the proposed method could improve overall image quality as compared to other methods. Our visual evaluation showed that an approximately 40% reduction in exposure dose might be achieved in hip joint radiography by using the proposed method.

  8. Optical radiation hazards of laser welding processes. Part II: CO2 laser.

    PubMed

    Rockwell, R J; Moss, C E

    1989-08-01

    There has been an extensive growth within the last five years in the use of high-powered lasers in various metalworking processes. The two types of lasers used most frequently for laser welding/cutting processes are the Neodymium-yttrium-aluminum-garnet (Nd:YAG) and the carbon dioxide (CO2) systems. When such lasers are operated in an open beam configuration, they are designated as a Class IV laser system. Class IV lasers are high-powered lasers that may present an eye and skin hazard under most common exposure conditions, either directly or when the beam has been diffusely scattered. Significant control measures are required for unenclosed (open beam), Class IV laser systems since workers may be exposed to scattered or reflected beams during the operation, maintenance, and service of these lasers. In addition to ocular and/or skin exposure hazards, such lasers also may present a multitude of nonlaser beam occupational concerns. Radiant energy measurements are reported for both the scattered laser radiation and the plasma-related plume radiations released during typical high-powered CO2 laser-target interactions. In addition, the application of the nominal hazard zone (NHZ) and other control measures also are discussed with special emphasis on Class IV industrial CO2 laser systems. PMID:2508455

  9. System of laser pump and synchrotron radiation probe microdiffraction to investigate optical recording process

    SciTech Connect

    Yasuda, Nobuhiro; Fukuyama, Yoshimitsu; Osawa, Hitoshi; Kimura, Shigeru; Ito, Kiminori; Tanaka, Yoshihito; Matsunaga, Toshiyuki; Kojima, Rie; Hisada, Kazuya; Tsuchino, Akio; Birukawa, Masahiro; Yamada, Noboru; Sekiguchi, Koji; Fujiie, Kazuhiko; Kawakubo, Osamu; Takata, Masaki

    2013-06-15

    We have developed a system of laser-pump and synchrotron radiation probe microdiffraction to investigate the phase-change process on a nanosecond time scale of Ge{sub 2}Sb{sub 2}Te{sub 5} film embedded in multi-layer structures, which corresponds to real optical recording media. The measurements were achieved by combining (i) the pump-laser system with a pulse width of 300 ps, (ii) a highly brilliant focused microbeam with wide peak-energy width ({Delta}E/E {approx} 2%) made by focusing helical undulator radiation without monochromatization, and (iii) a precise sample rotation stage to make repetitive measurements. We successfully detected a very weak time-resolved diffraction signal by using this system from 100-nm-thick Ge{sub 2}Sb{sub 2}Te{sub 5} phase-change layers. This enabled us to find the dependence of the crystal-amorphous phase change process of the Ge{sub 2}Sb{sub 2}Te{sub 5} layers on laser power.

  10. Two-dimensional signal processing and storage and theory and applications of electromagnetic measurements. Annual report, 1 January-31 December 1987

    SciTech Connect

    Schafer, R.W.; Paris, D.T.

    1988-01-01

    Specific topics covered are: digital signal processing, parallel-processing architectures, two-dimensional optical storage and processing, hybrid optical/digital signal processing, electromagnetic measurements in the time domain, and automatic radiation measurements for near and far-field transformations. Contents include: Periodic Scheduling Theory for DSP Multiprocessors; Zero-Reflectivity Surface Relief Gratings on Lossy Materials; Shaped Edge Serrations for Improved Reflector Performance; Iterative Signal Restoration and Estimation; Representation, Coding, and Analysis of Image; Multiprocessors for Digital Signal Processing; Two-Dimensional Optical Information Processing; Two-Dimensional Optical/Electronic Signal Processing; Electromagnetic Measurements in the Time and Frequency Domains; and Automated Measurements for Near- and Far-Field Transformations.

  11. The effect of free radical inhibitor on the sensitized radiation crosslinking and thermal processing stabilization of polyurethane shape memory polymers

    PubMed Central

    Hearon, Keith; Smith, Sarah E.; Maher, Cameron A.; Wilson, Thomas S.; Maitland, Duncan J.

    2012-01-01

    The effects of free radical inhibitor on the electron beam crosslinking and thermal processing stabilization of novel radiation crosslinkable polyurethane shape memory polymers (SMPs) blended with acrylic radiation sensitizers have been determined. The SMPs in this study possess novel processing capabilities—that is, the ability to be melt processed into complex geometries as thermoplastics and crosslinked in a secondary step using electron beam irradiation. To increase susceptibility to radiation crosslinking, the radiation sensitizer pentaerythritol triacrylate (PETA) was solution blended with thermoplastic polyurethane SMPs made from 2-butene-1,4-diol and trimethylhexamethylene diisocyanate (TMHDI). Because thermoplastic melt processing methods such as injection molding are often carried out at elevated temperatures, sensitizer thermal instability is a major processing concern. Free radical inhibitor can be added to provide thermal stabilization; however, inhibitor can also undesirably inhibit radiation crosslinking. In this study, we quantified both the thermal stabilization and radiation crosslinking inhibition effects of the inhibitor 1,4-benzoquinone (BQ) on polyurethane SMPs blended with PETA. Sol/gel analysis of irradiated samples showed that the inhibitor had little to no inverse effects on gel fraction at concentrations of 0-10,000 ppm, and dynamic mechanical analysis showed only a slight negative correlation between BQ composition and rubbery modulus. The 1,4-benzoquinone was also highly effective in thermally stabilizing the acrylic sensitizers. The polymer blends could be heated to 150°C for up to five hours or to 125°C for up to 24 hours if stabilized with 10,000 ppm BQ and could also be heated to 125°C for up to 5 hours if stabilized with 1000 ppm BQ without sensitizer reaction occurring. We believe this study provides significant insight into methods for manipulation of the competing mechanisms of radiation crosslinking and thermal

  12. Gamma radiation in the reduction of S almonella spp. inoculated on minimally processed watercress ( Nasturtium officinalis)

    NASA Astrophysics Data System (ADS)

    Martins, C. G.; Behrens, J. H.; Destro, M. T.; Franco, B. D. G. M.; Vizeu, D. M.; Hutzler, B.; Landgraf, M.

    2004-09-01

    Consumer attitudes towards foods have changed in the last two decades increasing requirements for freshlike products. Consequently, less extreme treatments or additives are being required. Minimally processed foods have freshlike characteristics and satisfy this new consumer demand. Besides freshness, the minimally processing also provide convenience required by the market. Salad vegetables can be source of pathogen such as Salmonella, Escherichia coli O157:H7, Shigella spp. The minimal processing does not reduce the levels of pathogenic microorganisms to safe levels. Therefore, this study was carried out in order to improve the microbiological safety and the shelf-life of minimally processed vegetables using gamma radiation. Minimally processed watercress inoculated with a cocktail of Salmonella spp was exposed to 0.0, 0.2, 0.5, 0.7, 1.0, 1.2 and 1.5 kGy. Irradiated samples were diluted 1:10 in saline peptone water and plated onto tryptic soy agar that were incubated at 37°C/24 h. D 10 values for Salmonella spp. inoculated in watercress varied from 0.29 to 0.43 kGy. Therefore, a dose of 1.7 kGy will reduce Salmonella population in watercress by 4 log 10. The shelf-life was increased by 1 {1}/{2} day when the product was exposed to 1 kGy.

  13. DOE 2009 occupational radiation exposure

    SciTech Connect

    none,

    2010-09-01

    The U.S. Department of Energy (DOE) Office of Corporate Safety Analysis (HS-30) within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE.* The DOE 2009 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with DOE Part 835 dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past 5 years.

  14. DOE 2010 occupational radiation exposure

    SciTech Connect

    none,

    2011-11-01

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE.* The DOE 2010 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with DOE Part 835 dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past 5 years.

  15. DOE 2008 occupational radiation exposure

    SciTech Connect

    none,

    2009-10-01

    The U.S. Department of Energy (DOE) Office of Corporate Safety Analysis (HS-30) within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE. The DOE 2008 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with DOE Part 835 dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the effects of radiation. This report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past 5 years.

  16. Terahertz radiation from bacteriorhodopsin reveals correlated primary electron and proton transfer processes

    PubMed Central

    Groma, G. I.; Hebling, J.; Kozma, I. Z.; Váró, G.; Hauer, J.; Kuhl, J.; Riedle, E.

    2008-01-01

    The kinetics of electrogenic events associated with the different steps of the light-induced proton pump of bacteriorhodopsin is well studied in a wide range of time scales by direct electric methods. However, the investigation of the fundamental primary charge translocation phenomena taking place in the functional energy conversion process of this protein, and in other biomolecular assemblies using light energy, has remained experimentally unfeasible because of the lack of proper detection technique operating in the 0.1- to 20-THz region. Here, we show that extending the concept of the familiar Hertzian dipole emission into the extreme spatial and temporal range of intramolecular polarization processes provides an alternative way to study ultrafast electrogenic events on naturally ordered biological systems. Applying a relatively simple experimental arrangement based on this idea, we were able to observe light-induced coherent terahertz radiation from bacteriorhodopsin with femtosecond time resolution. The detected terahertz signal was analyzed by numerical simulation in the framework of different models for the elementary polarization processes. It was found that the principal component of the terahertz emission can be well described by excited-state intramolecular electron transfer within the retinal chromophore. An additional slower process is attributed to the earliest phase of the proton pump, probably occurring by the redistribution of a H bond near the retinal. The correlated electron and proton translocation supports the concept, assigning a functional role to the light-induced sudden polarization in retinal proteins. PMID:18456840

  17. Fabrication process development for high-purity germanium radiation detectors with amorphous semiconductor contacts

    NASA Astrophysics Data System (ADS)

    Looker, Quinn

    High-purity germanium (HPGe) radiation detectors are well established as a valuable tool in nuclear science, astrophysics, and nuclear security applications. HPGe detectors excel in gamma-ray spectroscopy, offering excellent energy resolution with large detector sizes for high radiation detection efficiency. Although a robust fabrication process has been developed, improvement is needed, especially in developing electrical contact and surface passivation technology for position-sensitive detectors. A systematic study is needed to understand how the detector fabrication process impacts detector performance and reliability. In order to provide position sensitivity, the electrical contacts are segmented to form multiple electrodes. This segmentation creates new challenges in the fabrication process and warrants consideration of additional detector effects related to the segmentation. A key area of development is the creation of the electrical contacts in a way that enables reliable operation, provides low electronic noise, and allows fine segmentation of electrodes, giving position sensitivity for radiation interactions in the detector. Amorphous semiconductor contacts have great potential to facilitate new HPGe detector designs by providing a thin, high-resistivity surface coating that is the basis for electrical contacts that block both electrons and holes and can easily be finely segmented. Additionally, amorphous semiconductor coatings form a suitable passivation layer to protect the HPGe crystal surface from contamination. This versatility allows a simple fabrication process for fully passivated, finely segmented detectors. However, the fabrication process for detectors with amorphous semiconductors is not as highly developed as for conventional technologies. The amorphous semiconductor layer properties can vary widely based on how they are created and these can translate into varying performance of HPGe detectors with these contacts. Some key challenges include

  18. 1989 IEEE Annual Conference on Nuclear and Space Radiation Effects, 26th, Marco Island, FL, July 25-29, 1989, Proceedings. Part 1

    NASA Technical Reports Server (NTRS)

    Ochoa, Agustin, Jr. (Editor)

    1989-01-01

    Various papers on nuclear science are presented. The general topics addressed include: basic mechanics of radiation effects, dosimetry and energy-dependent effects, hardness assurance and testing techniques, spacecraft charging and space radiation effects, EMP/SGEMP/IEMP phenomena, device radiation effects and hardening, radiation effects on isolation technologies, IC radiation effects and hardening, and single-event phenomena.

  19. Theoretical studies relating to the interaction of radiation with matter: Atomic collision processes occurring in the presence of radiation fields

    NASA Astrophysics Data System (ADS)

    Berman, P. R.

    1981-09-01

    Work is reported in the areas of: Two-Level Atom and Radiation Pulse; Effects of Collisions on Atomic Coherences; Effects of Collisions on Zeeman Coherences; Collision Effects in Degenerate-Four-Wave-Mixing; and Dressed-Atom Picture in Laser Spectroscopy.

  20. Theoretical studies relating to the interaction of radiation with matter: Atomic collision processes occurring in the presence of radiation fields

    NASA Astrophysics Data System (ADS)

    Berman, P. R.

    1983-09-01

    Work is reported in the areas of: Saturation Spectroscopy; Heating and Cooling via Laser-Assisted Collisions; Creation of Electronic State Coherences via Laser-Assisted Collisions; Two-Level Atom Plus Radiation Pulse; Photon as Catalyst; and Collisional Effects in Four-Wave Mixing.

  1. Radiation processed polychloroprene-co-ethylene-propene diene terpolymer blends: Effect of radiation vulcanization on solvent transport kinetics

    NASA Astrophysics Data System (ADS)

    Dubey, K. A.; Bhardwaj, Y. K.; Chaudhari, C. V.; Kumar, Virendra; Goel, N. K.; Sabharwal, S.

    2009-03-01

    Blends of polychloroprene rubber (PCR) and ethylene propylene diene terpolymer rubber (EPDM) of different compositions were made and exposed to different gamma radiation doses. The radiation sensitivity and radiation vulcanization efficiency of blends was estimated by gel-content analysis, Charlesby-Pinner parameter determination and crosslinking density measurements. Gamma radiation induced crosslinking was most efficient for EPDM ( p0/ q0 ˜ 0.08), whereas it was the lowest for blends containing 40% PCR ( p0/ q0 ˜ 0.34). The vulcanized blends were characterized for solvent diffusion characteristics by following the swelling dynamics. Blends with higher PCR content showed anomalous swelling. The sorption and permeability of the solvent were not strictly in accordance with each other and the extent of variation in two parameters was found to be a function of blend composition. The Δ G values for solvent diffusion were in the range -2.97 to -9.58 kJ/mol and indicated thermodynamically favorable sorption for all blends. These results were corroborated by dynamic swelling, experimental as well as simulated profiles and have been explained on the basis of correlation between crosslinking density, diffusion kinetics, thermodynamic parameters and polymer-polymer interaction parameter.

  2. INTERACTION OF LASER RADIATION WITH MATTER: Influence of surface breakdown on the process of drilling metals with pulsed CO2 laser radiation

    NASA Astrophysics Data System (ADS)

    Arutyunyan, R. V.; Baranov, V. Yu; Bobkov, I. V.; Bol'shov, Leonid A.; Dolgov, V. A.; Kanevskiĭ, M. F.; Malyuta, D. D.; Mezhevov, V. S.

    1988-03-01

    A report is given of the influence of low-threshold surface optical breakdown, occurring under the action of short (~ 5-μs) radiation pulses from a CO2 laser, on the process of the laser drilling of metals. Data are given on the difference between the interaction of radiation pulses having the same duration but differing in shape. A study was made of the influence of the pressure of the atmosphere surrounding a target on the results of laser drilling of metals. A theoretical explanation is given of the experimental results.

  3. Studies on production of fructo-oligosaccharides (FOS) by gamma radiation processing of microbial levan.

    PubMed

    Jalan, N; Varshney, Lalit; Misra, Nilanjal; Paul, Jhimli; Mitra, D; Rairakhwada, D D; Bhathena, Z; Kumar, Virendra

    2013-07-01

    Microbial levan, a natural polymer of fructose, was produced and purified by alcohol precipitation from culture supernatants of Bacillus megaterium type 1 grown in an optimized liquid sucrose medium. GPC analysis showed that the yield of the major fraction of levan having molecular weight ~5000 D increased with increase in sucrose concentration in the broth. Levan subjected to (60)Co-gamma radiation as well as acid hydrolysis was investigated by rheometry, UV-visible spectrophotometry and gel permeation chromatography (GPC) techniques. Unlike most of the polysaccharides, levan powder exhibited good radiation degradation stability up to 150 kGy. Gamma irradiation of 10% levan aqueous solution at 250 kGy yielded 63.0% fructo-oligosaccharide (FOS) with an average molecular weight of 1250 D. Acid hydrolysis of levan using 0.5 N HCl for 60 min treatment time gave rise to the desired FOS with lower yield (23.1%) as compared to that obtained in gamma radiolysis process. PMID:23688493

  4. Phenol Photocatalytic Degradation by Advanced Oxidation Process under Ultraviolet Radiation Using Titanium Dioxide

    PubMed Central

    Nickheslat, Ali; Amin, Mohammad Mehdi; Izanloo, Hassan; Fatehizadeh, Ali; Mousavi, Seyed Mohammad

    2013-01-01

    Background. The main objective of this study was to examine the photocatalytic degradation of phenol from laboratory samples and petrochemical industries wastewater under UV radiation by using nanoparticles of titanium dioxide coated on the inner and outer quartz glass tubes. Method. The first stage of this study was conducted to stabilize the titanium dioxide nanoparticles in anatase crystal phase, using dip-coating sol-gel method on the inner and outer surfaces of quartz glass tubes. The effect of important parameters including initial phenol concentration, TiO2 catalyst dose, duration of UV radiation, pH of solution, and contact time was investigated. Results. In the dip-coat lining stage, the produced nanoparticles with anatase crystalline structure have the average particle size of 30 nm and are uniformly distributed over the tube surface. The removal efficiency of phenol was increased with the descending of the solution pH and initial phenol concentration and rising of the contact time. Conclusion. Results showed that the light easily passes through four layers of coating (about 105 nm). The highest removal efficiency of phenol with photocatalytic UV/TiO2 process was 50% at initial phenol concentration of 30 mg/L, solution pH of 3, and 300 min contact time. The comparison of synthetic solution and petrochemical wastewater showed that at same conditions the phenol removal efficiency was equal. PMID:23710198

  5. Process for crosslinking methylene-containing aromatic polymers with ionizing radiation

    NASA Technical Reports Server (NTRS)

    Bell, Vernon L. (Inventor); Havens, Stephen J. (Inventor)

    1990-01-01

    A process for crosslinking aromatic polymers containing radiation-sensitive methylene groups (-CH2-) by exposing the polymers to ionizing radiation thereby causing crosslinking of the polymers through the methylene groups is described. Crosslinked polymers are resistant to most organic solvents such as acetone, alcohols, hydrocarbons, methylene, chloride, chloroform, and other halogenated hydrocarbons, to common fuels and to hydraulic fluids in contrast to readily soluble uncrosslinked polymers. In addition, the degree of crosslinking of the polymers depends upon the percentage of the connecting groups which are methylene which ranges from 5 to 50 pct and preferably from 25 to 50 pct of the connecting groups, and is also controlled by the level of irradiation which ranges from 25 to 1000 Mrads and preferably from 25 to 250 Mrads. The temperature of the reaction conditions ranges from 25 to 200 C and preferably at or slightly above the glass transition temperature of the polymer. The crosslinked polymers are generally more resistant to degradation at elevated temperatures such as greater than 150 C, have a reduced tendency to creep under load, and show no significant embrittlement of parts fabricated from the polymers.

  6. Determine Important Nuclear Fragmentation Processes for Space Radiation Protection in Human Space Explorations

    NASA Technical Reports Server (NTRS)

    Lin, Zi-Wei

    2004-01-01

    Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most affect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space explorations.

  7. Determine Important Nuclear Fragmentation Processes for Space Radiation Protection in Human Space Explorations

    NASA Technical Reports Server (NTRS)

    Lin, Zi-wei

    2004-01-01

    Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most effect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space explorations.

  8. Determine Important Nuclear Fragmentation Processes for Space Radiation Protection in Human Space Explorations

    NASA Technical Reports Server (NTRS)

    Lin, Zi-Wei

    2004-01-01

    Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most affect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space exploration.

  9. Radiation enhanced diffusion processes in UO2 and (U,Pu)O2

    NASA Astrophysics Data System (ADS)

    Smirnov, E.; Elmanov, G.

    2016-04-01

    The diffusion mechanisms and migration characteristics of point defects in the fluorite structures of UO2 and (U, Pu) O2 were analyzed. The possibility of complex migration mechanisms of anionic and cationic vacancy and interstitial Frenkel defects depending on the stoichiometry of materials was shown.The statistical analysis of published data on the radiation-enhanced diffusion (RED) characteristics of metal atoms in UO2 and (U, Pu)O2 for temperatures 1303-1673 K was carried out. An approximate temperature dependence of RED coefficient was obtained. Within the framework of understanding of the mechanisms of diffusion processes in fluorite structure, the approximate temperature dependence of the RED coefficient of oxygen for UO2 and (U, Pu)O2 was proposed.

  10. Shelf-life extension of convenience meat products sold in Indian supermarkets by radiation processing

    NASA Astrophysics Data System (ADS)

    Kanatt, Sweetie R.; Shobita Rao, M.; Chawla, S. P.; Sharma, Arun

    2010-12-01

    A variety of ready-to-cook meat products available in Indian supermarkets (mutton mince, chicken mince, chicken chunks, and chicken legs) were studied. The samples were irradiated (2.5 kGy), or left untreated as control, and stored at 0-3 °C for up to 21 days. The effect of irradiation on the microbiological, chemical, and sensory properties was evaluated at intervals during the storage period. Irradiated samples had a longer shelf-life at 0-3 °C compared with the corresponding non-irradiated samples. Fecal coliforms were eliminated by irradiation treatment. Radiation processed samples had lower counts of Staphylococcus spp. There were no significant organoleptic changes in irradiated samples stored at chilled temperatures.

  11. Parallel multigrid solver of radiative transfer equation for photon transport via graphics processing unit.

    PubMed

    Gao, Hao; Phan, Lan; Lin, Yuting

    2012-09-01

    A graphics processing unit-based parallel multigrid solver for a radiative transfer equation with vacuum boundary condition or reflection boundary condition is presented for heterogeneous media with complex geometry based on two-dimensional triangular meshes or three-dimensional tetrahedral meshes. The computational complexity of this parallel solver is linearly proportional to the degrees of freedom in both angular and spatial variables, while the full multigrid method is utilized to minimize the number of iterations. The overall gain of speed is roughly 30 to 300 fold with respect to our prior multigrid solver, which depends on the underlying regime and the parallelization. The numerical validations are presented with the MATLAB codes at https://sites.google.com/site/rtefastsolver/. PMID:23085905

  12. Radiation processing as a post-harvest quarantine control for raisins, dried figs and dried apricots

    NASA Astrophysics Data System (ADS)

    Cetinkaya, N.; Ozyardımci, B.; Denli, E.; Ic, E.

    2006-03-01

    The commercially packed samples of raisins, dried figs and dried apricots were irradiated using doses in the range of 0.5-1.0 kGy for disinfestation and 0.5-5.0 kGy for sensory analysis with the dose rate ranging from 1.44 to 1.92 kGy/h. Pests on dried fruits were evaluated after 0, 1, 2 and 3 months of storage for irradiated dried figs and 1, 3, 6 and 12 months of storage for raisins and dried apricots. Sensory analysis of dried figs, dried apricots and raisins were carried out after 0, 1, 3, 6 and 12 months of storage. The results indicated that radiation processing at low doses, (˜1.0 kGy) is an effective post-harvest treatment and quarantine control for these products with no adverse effects on sensory (marketing) attributes.

  13. Time-resolved resonance Raman spectroscopy of radiation-chemical processes. [Pulsed irradiation

    SciTech Connect

    Tripathi, G.N.R.

    1983-01-01

    A tunable pulsed laser Raman spectrometer for time resolved Raman studies of radiation-chemical processes is described. This apparatus utilizes the state of art optical multichannel detection and analysis techniques for data acquisition and electron pulse radiolysis for initiating the reactions. By using this technique the resonance Raman spectra of intermediates with absorption spectra in the 248-900 nm region, and mean lifetimes > 30 ns can be examined. This apparatus can be used to time resolve the vibrational spectral overlap between transients absorbing in the same region, and to follow their decay kinetics by monitoring the well resolved Raman peaks. For kinetic measurements at millisecond time scale, the Raman technique is preferable over optical absorption method where low frequency noise is quite bothersome. A time resolved Raman study of the pulse radiolytic oxidation of aqueous tetrafluorohydroquinone and p-methoxyphenol is briefly discussed. 15 references, 5 figures.

  14. Chemical process yielding stimulating emission of visible radiation via fast near resonant energy transfer

    SciTech Connect

    Gole, J.L.; Woodward, J.R.; Cobb, S.H.

    1991-05-28

    This patent describes a chemical process yielding stimulated emission of visible radiation via fast rear resonant intermolecular energy transfer. It comprises: providing a first source of vapor selected from the group consisting of metal or semimetal vapor; providing a second source of atomic vapor selected from the group consisting of metal or semimetal vapor to serve as receptor atoms to receive the energy; providing a source of reactant to react with the first source of vapor in a highly exothermic reaction which liberates energy exceeding 2.5 eV; chemically reacting the reactant and the first source of vapor to form metastable states of a final reaction product; transferring energy stored in the metastable states of the the reaction product to the second source of atomic vapor serving as receptor atoms by means of near resonant energy transfer; and providing a mirror configuration having first and second mirrors and windows associated with the mirrors.

  15. Separation of radiation induced and process induced lateral non-uniformities

    NASA Astrophysics Data System (ADS)

    Xapsos, M. A.; Freitag, R. K.; Dozier, C. M.; Brown, D. B.; Summers, G. P.

    1990-12-01

    Fast measurements of channel current versus gate voltage (I-V) were performed on irradiated MOSFETs as a function of time and temperature after pulsed proton irradiation. Stretchout of the I-V curves due to lateral nonuniformities (LNUs) in the hole distribution in the oxide is shown to be experimentally separable from stretchout due to interface traps. The stretchout due to LNUs is then shown to consist of two experimentally separable components-one due to the random production of holes by the radiation, and one due to the random distribution of hole traps in the oxide. This suggests an entirely new approach for evaluating the quality of oxides in terms of the microscopic uniformity of the processing.

  16. Review of measurement techniques for the neutron radiative-capture process

    SciTech Connect

    Poenitz, W.P.

    1981-07-01

    The experimental techniques applied in measurements of the neutron capture process are reviewed. The emphasis is on measurement techniques used in neutron capture cross section measurements. The activation technique applied mainly in earlier work has still its use in some cases, specifically for measurements of technologically important cross sections (/sup 238/U and /sup 232/Th) with high accuracy. Three major prompt neutron radioactive capture detection techniques have evolved: the total gamma radiation energy detection technique (mainly with large liquid scintillation detectors), the gamma-energy proportional detectors (with proportional counters or Moxon-Rae detectors), and the pulse-height weighting technique. These measurement techniques are generally applicable, however, shortcomings limit the achievable accuracy to a approx. = 5 to 15% uncertainty level.

  17. Evaluation of the analgesic effect of low-power optical radiation in acute inflammatory process

    NASA Astrophysics Data System (ADS)

    Ferreira, Denise M.; Zangaro, Renato A.; Cury, Yara; Frigo, Lucio; Barbosa, Daniella G.; da Silva Melo, Milene; Munin, Egberto

    2004-07-01

    Many research works have explored the use of the low power laser as a tool for the control of inflammatory processes. The anti-inflammatory effect of low power optical radiation and its ability to induce analgesia has been reported for different experimental conditions. Many published works are very qualitative in nature. In this work the action of low power laser radiation on acute inflammatory process is evaluated. The time evolution of rat paw edema and pain induced by carrageenan was experimentally monitored. A 632.8 nm He-Ne laser was used for the treatment. The laser treatment, at a dosage of 2,5 J/cm2, was applied at the first, second and third hour after the induction of the inflammation. A hydroplethysmometer was used for the evaluation of the inflammation. The measurement of pain sensitivity was performed according to the method described by Randall and Selito, (1957). The laser treatment was capable of inhibiting the carrageenan-induced hyperalgesia by 49% (p<0,001) at the second hour after the induction, as compared to the non-treated group. At the fourth hour (peak of the carrageenan action on hyperalgesia) and at the sixth hour, the achieved inhibition was 49% (p<0,001) and 61% (p<0,001), respectively. In the treated groups, the edema evolution was inhibited by 38% (p<0,01), at the second hour after induction, as compared to the non-treated groups. At the fourth hour (peak of the carrageenan action on leakage) and at sixth hour the achieved inhibition was 35% (p<0,01) and 30% (p<0,05) respectively.

  18. PREFACE: International Scientific Conference on Radiation-Thermal Effects and Processes in Inorganic Materials 2015 (RTEP2015)

    NASA Astrophysics Data System (ADS)

    2016-02-01

    The International Scientific Conference "Radiation-Thermal Effects and Processes in Inorganic Materials" is a traditional representative forum devoted to the discussion of fundamental problems of radiation physics and its technical applications. The first nine conferences were held fourfold in Tomsk, Ulan-Ude (Russia), Bishkek (Kyrgyzstan), Tashkent (Uzbekistan), Sharm El Sheikh (Egypt), the island of Cyprus. The XI conference was held in Tomsk, Russia. The program of the Conference covers a wide range of technical areas and modern aspects of radiation physics, its applications and related matters. Topics of interest include, but are not limited to: • Physical and chemical phenomena in inorganic materials in radiation, electrical and thermal fields; • Research methods and equipment modification states and properties of materials; • Technologies and equipment for their implementation; • The use of radiation-thermal processes in nanotechnology; • Adjacent to the main theme of the conference issues The conference was attended by leading scientists from countries near and far abroad who work in the field of radiation physics of solid state and of radiation material science. The School-Conference of Young Scientists was also held during the conference. The event was held with the financial support of the Russian Foundation for Basic Research, projects № 15-02-20616.

  19. PREFACE: International Scientific Conference on Radiation-Thermal Effects and Processes in Inorganic Materials 2015 (RTEP2015)

    NASA Astrophysics Data System (ADS)

    2016-02-01

    The International Scientific Conference "Radiation-Thermal Effects and Processes in Inorganic Materials" is a traditional representative forum devoted to the discussion of fundamental problems of radiation physics and its technical applications. The first nine conferences were held fourfold in Tomsk, Ulan-Ude (Russia), Bishkek (Kyrgyzstan), Tashkent (Uzbekistan), Sharm El Sheikh (Egypt), the island of Cyprus. The XI conference was held in Tomsk, Russia. The program of the Conference covers a wide range of technical areas and modern aspects of radiation physics, its applications and related matters. Topics of interest include, but are not limited to: • Physical and chemical phenomena in inorganic materials in radiation, electrical and thermal fields; • Research methods and equipment modification states and properties of materials; • Technologies and equipment for their implementation; • The use of radiation-thermal processes in nanotechnology; • Adjacent to the main theme of the conference issues The conference was attended by leading scientists from countries near and far abroad who work in the field of radiation physics of solid state and of radiation material science. The School-Conference of Young Scientists was also held during the conference. The event was held with the financial support of the Russian Foundation for Basic Research, projects No. 15-02-20616.

  20. Non-Radiative Carrier Recombination Enhanced by Two-Level Process: A First-Principles Study

    PubMed Central

    Yang, Ji-Hui; Shi, Lin; Wang, Lin-Wang; Wei, Su-Huai

    2016-01-01

    Non-radiative recombination plays an important role in the performance of optoelectronic semiconductor devices such as solar cells and light-emitting diodes. Most textbook examples assume that the recombination process occurs through a single defect level, where one electron and one hole are captured and recombined. Based on this simple picture, conventional wisdom is that only defect levels near the center of the bandgap can be effective recombination centers. Here, we present a new two-level recombination mechanism: first, one type of carrier is captured through a defect level forming a metastable state; then the local defect configuration rapidly changes to a stable state, where the other type of carrier is captured and recombined through another defect level. This novel mechanism is applied to the recombination center in CdTe. We show that this two-level process can significantly increase the recombination rate (by three orders of magnitude) in agreement with experiments. We expect that this two-level recombination process can exist in a wide range of semiconductors, so its effect should be carefully examined in characterizing optoelectronic materials. PMID:26880667

  1. Non-Radiative Carrier Recombination Enhanced by Two-Level Process: A First-Principles Study

    NASA Astrophysics Data System (ADS)

    Yang, Ji-Hui; Shi, Lin; Wang, Lin-Wang; Wei, Su-Huai

    2016-02-01

    Non-radiative recombination plays an important role in the performance of optoelectronic semiconductor devices such as solar cells and light-emitting diodes. Most textbook examples assume that the recombination process occurs through a single defect level, where one electron and one hole are captured and recombined. Based on this simple picture, conventional wisdom is that only defect levels near the center of the bandgap can be effective recombination centers. Here, we present a new two-level recombination mechanism: first, one type of carrier is captured through a defect level forming a metastable state; then the local defect configuration rapidly changes to a stable state, where the other type of carrier is captured and recombined through another defect level. This novel mechanism is applied to the recombination center in CdTe. We show that this two-level process can significantly increase the recombination rate (by three orders of magnitude) in agreement with experiments. We expect that this two-level recombination process can exist in a wide range of semiconductors, so its effect should be carefully examined in characterizing optoelectronic materials.

  2. Ab initio calculation of the $np \\to d ³$ radiative capture process

    SciTech Connect

    Beane, Silas R.; Chang, Emmanuel; Detmold, William; Orginos, Kostas; Parreño, Assumpta; Savage, Martin J.; Tiburzi, Brian C.

    2015-09-24

    In this study, lattice QCD calculations of two-nucleon systems are used to isolate the short-distance two-body electromagnetic contributions to the radiative capture process $np \\to d\\gamma$, and the photo-disintegration processes $\\gamma^{(\\ast)} d \\to np$. In nuclear potential models, such contributions are described by phenomenological meson-exchange currents, while in the present work, they are determined directly from the quark and gluon interactions of QCD. Calculations of neutron-proton energy levels in multiple background magnetic fields are performed at two values of the quark masses, corresponding to pion masses of $m_\\pi \\sim 450$ and 806 MeV, and are combined with pionless nuclear effective field theory to determine these low-energy inelastic processes. Extrapolating to the physical pion mass, a cross section of $\\sigma^{lqcd}(np\\to d\\gamma)=332.4({\\tiny \\begin{array}{l}+5.4 \\\\ - 4.7\\end{array}})\\ mb$ is obtained at an incident neutron speed of $v=2,200\\ m/s$, consistent with the experimental value of $\\sigma^{expt}(np \\to d\\gamma) = 334.2(0.5)\\ mb$.

  3. Probing polymer crystallization at processing-relevant cooling rates with synchrotron radiation

    SciTech Connect

    Cavallo, Dario; Portale, Giuseppe; Androsch, René

    2015-12-17

    Processing of polymeric materials to produce any kind of goods, from films to complex objects, involves application of flow fields on the polymer melt, accompanied or followed by its rapid cooling. Typically, polymers solidify at cooling rates which span over a wide range, from a few to hundreds of °C/s. A novel method to probe polymer crystallization at processing-relevant cooling rates is proposed. Using a custom-built quenching device, thin polymer films are ballistically cooled from the melt at rates between approximately 10 and 200 °C/s. Thanks to highly brilliant synchrotron radiation and to state-of-the-art X-ray detectors, the crystallization process is followed in real-time, recording about 20 wide angle X-ray diffraction patterns per second while monitoring the instantaneous sample temperature. The method is applied to a series of industrially relevant polymers, such as isotactic polypropylene, its copolymers and virgin and nucleated polyamide-6. Their crystallization behaviour during rapid cooling is discussed, with particular attention to the occurrence of polymorphism, which deeply impact material’s properties.

  4. Non-radiative carrier recombination enhanced by two-level process: A first-principles study

    DOE PAGESBeta

    Yang, Ji -Hui; Shi, Lin; Wang, Lin -Wang; Wei, Su -Huai

    2016-02-16

    In this study, non-radiative recombination plays an important role in the performance of optoelectronic semiconductor devices such as solar cells and light-emitting diodes. Most textbook examples assume that the recombination process occurs through a single defect level, where one electron and one hole are captured and recombined. Based on this simple picture, conventional wisdom is that only defect levels near the center of the bandgap can be effective recombination centers. Here, we present a new two-level recombination mechanism: first, one type of carrier is captured through a defect level forming a metastable state; then the local defect configuration rapidly changesmore » to a stable state, where the other type of carrier is captured and recombined through another defect level. This novel mechanism is applied to the recombination center Te2+cd in CdTe. We show that this two-level process can significantly increase the recombination rate (by three orders of magnitude) in agreement with experiments. We expect that this two-level recombination process can exist in a wide range of semiconductors, so its effect should be carefully examined in characterizing optoelectronic materials.« less

  5. Ab initio Calculation of the np→dγ Radiative Capture Process.

    PubMed

    Beane, Silas R; Chang, Emmanuel; Detmold, William; Orginos, Kostas; Parreño, Assumpta; Savage, Martin J; Tiburzi, Brian C

    2015-09-25

    Lattice QCD calculations of two-nucleon systems are used to isolate the short-distance two-body electromagnetic contributions to the radiative capture process np→dγ, and the photo-disintegration processes γ^{(*)}d→np. In nuclear potential models, such contributions are described by phenomenological meson-exchange currents, while in the present work, they are determined directly from the quark and gluon interactions of QCD. Calculations of neutron-proton energy levels in multiple background magnetic fields are performed at two values of the quark masses, corresponding to pion masses of m_{π}~450 and 806 MeV, and are combined with pionless nuclear effective field theory to determine the amplitudes for these low-energy inelastic processes. At m_{π}~806 MeV, using only lattice QCD inputs, a cross section σ^{806 MeV}~17 mb is found at an incident neutron speed of v=2,200 m/s. Extrapolating the short-distance contribution to the physical pion mass and combining the result with phenomenological scattering information and one-body couplings, a cross section of σ^{lqcd}(np→dγ)=334.9(+5.2-5.4) mb is obtained at the same incident neutron speed, consistent with the experimental value of σ^{expt}(np→dγ)=334.2(0.5) mb. PMID:26451545

  6. Non-Radiative Carrier Recombination Enhanced by Two-Level Process: A First-Principles Study.

    PubMed

    Yang, Ji-Hui; Shi, Lin; Wang, Lin-Wang; Wei, Su-Huai

    2016-01-01

    Non-radiative recombination plays an important role in the performance of optoelectronic semiconductor devices such as solar cells and light-emitting diodes. Most textbook examples assume that the recombination process occurs through a single defect level, where one electron and one hole are captured and recombined. Based on this simple picture, conventional wisdom is that only defect levels near the center of the bandgap can be effective recombination centers. Here, we present a new two-level recombination mechanism: first, one type of carrier is captured through a defect level forming a metastable state; then the local defect configuration rapidly changes to a stable state, where the other type of carrier is captured and recombined through another defect level. This novel mechanism is applied to the recombination center Te(cd)(2+) in CdTe. We show that this two-level process can significantly increase the recombination rate (by three orders of magnitude) in agreement with experiments. We expect that this two-level recombination process can exist in a wide range of semiconductors, so its effect should be carefully examined in characterizing optoelectronic materials. PMID:26880667

  7. Application of an Informatics-Based Decision-Making Framework and Process to the Assessment of Radiation Safety in Nanotechnology

    DOE PAGESBeta

    Hoover, Mark D.; Myers, David S.; Cash, Leigh J.; Guilmette, Raymond A.; Kreyling, Wolfgang G.; Oberdörster, Günter; Smith, Rachel; Cassata, James R.; Boecker, Bruce B.; Grissom, Michael P.

    2015-01-01

    The National Council on Radiation Protection and Measurements (NCRP) has established NCRP Scientific Committee 2-6 to develop a report on the current state of knowledge and guidance for radiation safety programs involved with nanotechnology. Nanotechnology is the understanding and control of matter at the nanoscale, at dimensions between approximately 1 and 100 nanometers, where unique phenomena enable novel applications. While the full report is in preparation, this article presents and applies an informatics-based decision-making framework and process through which the radiation protection community can anticipate that nano-enabled applications, processes, nanomaterials, and nanoparticles are likely to become present or are alreadymore » present in radiation-related activities; recognize specific situations where environmental and worker safety, health, well-being, and productivity may be affected by nano-related activities; evaluate how radiation protection practices may need to be altered to improve protection; control information, interpretations, assumptions, and conclusions to implement scientifically sound decisions and actions; and confirm that desired protection outcomes have been achieved. This generally applicable framework and supporting process can be continuously applied to achieve health and safety at the convergence of nanotechnology and radiation-related activities.« less

  8. Application of an Informatics-Based Decision-Making Framework and Process to the Assessment of Radiation Safety in Nanotechnology

    SciTech Connect

    Hoover, Mark D.; Myers, David S.; Cash, Leigh J.; Guilmette, Raymond A.; Kreyling, Wolfgang G.; Oberdörster, Günter; Smith, Rachel; Cassata, James R.; Boecker, Bruce B.; Grissom, Michael P.

    2015-01-01

    The National Council on Radiation Protection and Measurements (NCRP) has established NCRP Scientific Committee 2-6 to develop a report on the current state of knowledge and guidance for radiation safety programs involved with nanotechnology. Nanotechnology is the understanding and control of matter at the nanoscale, at dimensions between approximately 1 and 100 nanometers, where unique phenomena enable novel applications. While the full report is in preparation, this article presents and applies an informatics-based decision-making framework and process through which the radiation protection community can anticipate that nano-enabled applications, processes, nanomaterials, and nanoparticles are likely to become present or are already present in radiation-related activities; recognize specific situations where environmental and worker safety, health, well-being, and productivity may be affected by nano-related activities; evaluate how radiation protection practices may need to be altered to improve protection; control information, interpretations, assumptions, and conclusions to implement scientifically sound decisions and actions; and confirm that desired protection outcomes have been achieved. This generally applicable framework and supporting process can be continuously applied to achieve health and safety at the convergence of nanotechnology and radiation-related activities.

  9. Radiative effects in the processes of exclusive photon electroproduction from polarized protons

    SciTech Connect

    Igor Akushevich, Alexander Ilyichev

    2012-03-01

    Radiative effects in the electroproduction of photons in polarized ep-scattering are calculated in the leading log approximation and analyzed numerically for kinematical conditions of current measurement at Jefferson Lab. Radiative corrections to the cross sections, their azimuthal distributions and Fourier coefficients are in particular focus. Kinematical regions where the radiative corrections are considerable are identified.

  10. Two-parametric model of electron beam in computational dosimetry for radiation processing

    NASA Astrophysics Data System (ADS)

    Lazurik, V. M.; Lazurik, V. T.; Popov, G.; Zimek, Z.

    2016-07-01

    Computer simulation of irradiation process of various materials with electron beam (EB) can be applied to correct and control the performances of radiation processing installations. Electron beam energy measurements methods are described in the international standards. The obtained results of measurements can be extended by implementation computational dosimetry. Authors have developed the computational method for determination of EB energy on the base of two-parametric fitting of semi-empirical model for the depth dose distribution initiated by mono-energetic electron beam. The analysis of number experiments show that described method can effectively consider random displacements arising from the use of aluminum wedge with a continuous strip of dosimetric film and minimize the magnitude uncertainty value of the electron energy evaluation, calculated from the experimental data. Two-parametric fitting method is proposed for determination of the electron beam model parameters. These model parameters are as follow: E0 - energy mono-energetic and mono-directional electron source, X0 - the thickness of the aluminum layer, located in front of irradiated object. That allows obtain baseline data related to the characteristic of the electron beam, which can be later on applied for computer modeling of the irradiation process. Model parameters which are defined in the international standards (like Ep- the most probably energy and Rp - practical range) can be linked with characteristics of two-parametric model (E0, X0), which allows to simulate the electron irradiation process. The obtained data from semi-empirical model were checked together with the set of experimental results. The proposed two-parametric model for electron beam energy evaluation and estimation of accuracy for computational dosimetry methods on the base of developed model are discussed.

  11. Annual Conference on Nuclear and Space Radiation Effects, 17th, Cornell University, Ithaca, N.Y., July 15-18, 1980, Proceedings

    NASA Technical Reports Server (NTRS)

    Mcgarrity, J. M.

    1980-01-01

    The conference covered the radiation effects on devices, circuits, and systems, physics and basic radiation effects in materials, dosimetry and radiation transport, spacecraft charging, and space radiation effects. Other subjects included single particle upset phenomena, systems-generated electromagnetic pulse phenomena, fabrication of hardened components, testing techniques, and hardness assurance.

  12. Radiative levitation in carbon-enhanced metal-poor stars with s-process enrichment

    NASA Astrophysics Data System (ADS)

    Matrozis, E.; Stancliffe, R. J.

    2016-07-01

    A significant fraction of all metal-poor stars are carbon-rich. Most of these carbon-enhanced metal-poor (CEMP) stars also show enhancement in elements produced mainly by the s-process (CEMP-s stars), and evidence suggests that the origin of these non-standard abundances can be traced to mass transfer from a binary asymptotic giant branch (AGB) companion. Thus, observations of CEMP-s stars are commonly used to infer the nucleosynthesis output of low-metallicity AGB stars. A crucial step in this exercise is understanding what happens to the accreted material after mass transfer ceases. Here we present models of the post-mass-transfer evolution of CEMP-s stars considering the physics of thermohaline mixing and atomic diffusion, including radiative levitation. We find that stars with typical CEMP-s star masses, M ≈ 0.85 M⊙, have very shallow convective envelopes (Menv ≲ 10-7 M⊙). Hence, the surface abundance variations arising from the competition between gravitational settling and radiative levitation should be orders of magnitude larger than observed (e.g. [C/Fe] < -1 or [C/Fe] > +4). Lower-mass stars (M ≈ 0.80 M⊙) retain thicker convective envelopes and thus show variations more in line with observations, but are generally too unevolved (log g > 4) when they reach the age of the Universe. We are therefore unable to reproduce the spread in the observed abundances with these models and conclude that some other physical process must largely suppress atomic diffusion in the outer layers of CEMP-s stars. We demonstrate that this could be achieved by some additional (turbulent) mixing process operating at the base of the convective envelope, as found by other authors. Alternatively, mass-loss rates around 10-13 M⊙yr-1 could also negate most of the abundance variations by eroding the surface layers and forcing the base of the convective envelope to move inwards in mass. Since atomic diffusion cannot have a substantial effect on the surface abundances of CEMP

  13. Ab initio calculation of the $$np \\to d ³$$ radiative capture process

    DOE PAGESBeta

    Beane, Silas R.; Chang, Emmanuel; Detmold, William; Orginos, Kostas; Parreño, Assumpta; Savage, Martin J.; Tiburzi, Brian C.

    2015-09-24

    In this study, lattice QCD calculations of two-nucleon systems are used to isolate the short-distance two-body electromagnetic contributions to the radiative capture processmore » $$np \\to d\\gamma$$, and the photo-disintegration processes $$\\gamma^{(\\ast)} d \\to np$$. In nuclear potential models, such contributions are described by phenomenological meson-exchange currents, while in the present work, they are determined directly from the quark and gluon interactions of QCD. Calculations of neutron-proton energy levels in multiple background magnetic fields are performed at two values of the quark masses, corresponding to pion masses of $$m_\\pi \\sim 450$$ and 806 MeV, and are combined with pionless nuclear effective field theory to determine these low-energy inelastic processes. Extrapolating to the physical pion mass, a cross section of $$\\sigma^{lqcd}(np\\to d\\gamma)=332.4({\\tiny \\begin{array}{l}+5.4 \\\\ - 4.7\\end{array}})\\ mb$$ is obtained at an incident neutron speed of $$v=2,200\\ m/s$$, consistent with the experimental value of $$\\sigma^{expt}(np \\to d\\gamma) = 334.2(0.5)\\ mb$$.« less

  14. Estimation of the absorbed dose in radiation-processed food. 4. EPR measurements on eggshell

    SciTech Connect

    Desrosiers, M.F.; Le, F.G. ); Harewood, P.M.; Josephson, E.S. ); Montesalvo, M. )

    1993-09-01

    Fresh whole eggs treated with ionizing radiation for Salmonellae control testing. The eggshell was then removed and examined by electron paramagnetic resonance (EPR) spectroscopy to determine if EPR could be used to (1) distinguish irradiated from unirradiated eggs and (2) assess the absorbed dose. No EPR signals were detected in unirradiated eggs, while strong signals were measurable for more than 200 days after irradiation. Although a number of EPR signals were measured, the most intense resonance (g = 2.0019) was used for dosimetry throughout the study. This signal was observed to increase linearly with dose (up to [approximately]6 kGy), which decayed [approximately]20% within the first 5 days after irradiation and remained relatively constant thereafter. The standard added-dose method was used to assess, retrospectively, the dose to eggs processed at 0.2, 0.7, and 1.4 kGy. Relatively good results were obtained when measurement was made on the day the shell was reirradiated; with this procedure estimates were better for shell processed at the lower doses.

  15. Experimental Investigation of Space Radiation Processing in Lunar Soil Ilmenite: Combining Perspectives from Surface Science and Transmission Electron Microscopy

    NASA Technical Reports Server (NTRS)

    Christoffersen, R.; Keller, L. P.; Rahman, Z.; Baragiola, R.

    2010-01-01

    Energetic ions mostly from the solar wind play a major role in lunar space weathering because they contribute structural and chemical changes to the space-exposed surfaces of lunar regolith grains. In mature mare soils, ilmenite (FeTiO3) grains in the finest size fraction have been shown in transmission electron microscope (TEM) studies to exhibit key differences in their response to space radiation processing relative to silicates [1,2,3]. In ilmenite, solar ion radiation alters host grain outer margins to produce 10-100 nm thick layers that are microstructurally complex, but dominantly crystalline compared to the amorphous radiation-processed rims on silicates [1,2,3]. Spatially well-resolved analytical TEM measurements also show nm-scale compositional and chemical state changes in these layers [1,3]. These include shifts in Fe/Ti ratio from strong surface Fe-enrichment (Fe/Ti >> 1), to Fe depletion (Fe/Ti < 1) at 40-50 nm below the grain surface [1,3]. These compositional changes are not observed in the radiation-processed rims on silicates [4]. Several mechanism(s) to explain the overall relations in the ilmenite grain rims by radiation processing and/or additional space weathering processes were proposed by [1], and remain under current consideration [3]. A key issue has concerned the ability of ion radiation processing alone to produce some of the deeper- penetrating compositional changes. In order to provide some experimental constraints on these questions, we have performed a combined X-ray photoelectron spectroscopy (XPS) and field-emission scanning transmission electron (FE-STEM) study of experimentally ion-irradiated ilmenite. A key feature of this work is the combination of analytical techniques sensitive to changes in the irradiated samples at depth scales going from the immediate surface (approx.5 nm; XPS), to deeper in the grain interior (5-100 nm; FE-STEM).

  16. XIIth international meeting on radiation processing Avignon 25-30 March 2001 (Polymer irradiation: past-present and future)

    NASA Astrophysics Data System (ADS)

    Chapiro, Adolphe

    2002-03-01

    Radiations are used efficiently and economically for the production of new or modified polymers. The following processes are considered: Radiation curing; Radiation cross-linking; Radiation grafting. These processes are commonly used today in industry and provide a broad range of new potential applications in various fields. The history of their development is briefly reported. The chemical reactions underlying these processes are described. (1) Radiation curing is used commercially on a large scale for the production of improved coatings, lacquers and inks. The process can be conducted at very high speeds. Curing of magnetic formulations leads to particularly stable products, which compete favourably with more conventional materials. (2) Radiation cross-linking is an established technology in the wire and cable industry. It emparts to the modified insulators improved resistance to solvents, to ageing and to elevated temperatures. The resulting cross-linked network also reduces the migration of fillers and thereby stabilizes in time any message imprinted with magnetic or colored pigments dispersed in a polymer. (3) Radiation grafting is a powerful method for modifying more profoundly the properties of a polymer and for creating numerous, entirely new materials. The chemical modification can be applied at will into the bulk of the material or limited to a surface zone of any desired depth. This method can be used for instance, for introducing polar groups in the bulk or on the surface of non-polar polymers, for increasing or reducing the wettability of a polymer, for imparting a better compatibility of a polymer to a specific coating and the like. The irradiation of water-soluble polymers in aqueous solutions, with or without the addition of another monomer gives rise to a variety of cross-linked gels which find useful applications in the biomedical field. Other promising applications will be considered.

  17. Prospect on the Atomic and Molecular Processes in Plasmas 4. Transport Code 4.1 Radiation Transport Code

    NASA Astrophysics Data System (ADS)

    Takabe, Hideaki

    A brief review is given of the physics of radiation transport, a topic that is important in the study of astrophysics, laser-plasmas, divertor-plasmas, etc. In general, we must solve non-local thermodynamic equilibrium processes using an appropriate atomic model. The resultant data related to the spectral emissivity and opacity of partially ionized plasmas are then used to solve the radiation transfer equation. In this note, I briefly overview a variety of ways to carry out such a calculation. In addition, similarities and differences in the physical process between laser-plasmas and divertor-plasmas are briefly described.

  18. QED radiative effects in the processes of exclusive photon electroproduction from polarized protons with the next-to-leading accuracy

    SciTech Connect

    Akushevich, Igor V.; Ilyichev, Alexander; Shumeiko, Nikolai M

    2014-08-01

    Radiative effects in the electroproduction of photons in polarized ep-scattering are calculated with the next-to-leading (NLO) accuracy. The contributions of loops and two photon emission were presented in analytical form. The covariant approach of Bardin and Shumeiko was used to extract the infrared divergence. All contributions to the radiative correction were presented in the form of the correction to the leptonic tensor thus allowing for further applications in other experiments, e.g., deep inelastic scattering. The radiative corrections (RC) to the cross sections and polarization asymmetries were analyzed numerically for kinematical conditions of the current measurement at Jefferson Lab. Specific attention was paid on analyzing kinematical conditions for the process with large radiative effect when momenta of two photons in the final state are collinear to momenta of initial and final electrons, respectively.

  19. Contribution to the beam plasma material interactions during material processing with TEA CO2 laser radiation

    NASA Astrophysics Data System (ADS)

    Jaschek, Rainer; Konrad, Peter E.; Mayerhofer, Roland; Bergmann, Hans W.; Bickel, Peter G.; Kowalewicz, Roland; Kuttenberger, Alfred; Christiansen, Jens

    1995-03-01

    The TEA-CO2-laser (transversely excited atmospheric pressure) is a tool for the pulsed processing of materials with peak power densities up to 1010 W/cm2 and a FWHM of 70 ns. The interaction between the laser beam, the surface of the work piece and the surrounding atmosphere as well as gas pressure and the formation of an induced plasma influences the response of the target. It was found that depending on the power density and the atmosphere the response can take two forms. (1) No target modification due to optical break through of the atmosphere and therefore shielding of the target (air pressure above 10 mbar, depending on the material). (2) Processing of materials (air pressure below 10 mbar, depending on the material) with melting of metallic surfaces (power density above 0.5 109 W/cm2), hole formation (power density of 5 109 W/cm2) and shock hardening (power density of 3.5 1010 W/cm2). All those phenomena are usually linked with the occurrence of laser supported combustion waves and laser supported detonation waves, respectively for which the mechanism is still not completely understood. The present paper shows how short time photography and spatial and temporal resolved spectroscopy can be used to better understand the various processes that occur during laser beam interaction. The spectra of titanium and aluminum are observed and correlated with the modification of the target. If the power density is high enough and the gas pressure above a material and gas composition specific threshold, the plasma radiation shows only spectral lines of the background atmosphere. If the gas pressure is below this threshold, a modification of the target surface (melting, evaporation and solid state transformation) with TEA-CO2- laser pulses is possible and the material specific spectra is observed. In some cases spatial and temporal resolved spectroscopy of a plasma allows the calculation of electron temperatures by comparison of two spectral lines.

  20. Tropical Convective Responses to Microphysical and Radiative Processes: A Sensitivity Study With a 2D Cloud Resolving Model

    NASA Technical Reports Server (NTRS)

    Li, Xiao-Fan; Sui, C.-H.; Lau, K.-M.; Tao, W.-K.

    2004-01-01

    Prognostic cloud schemes are increasingly used in weather and climate models in order to better treat cloud-radiation processes. Simplifications are often made in such schemes for computational efficiency, like the scheme being used in the National Centers for Environment Prediction models that excludes some microphysical processes and precipitation-radiation interaction. In this study, sensitivity tests with a 2D cloud resolving model are carried out to examine effects of the excluded microphysical processes and precipitation-radiation interaction on tropical thermodynamics and cloud properties. The model is integrated for 10 days with the imposed vertical velocity derived from the Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment. The experiment excluding the depositional growth of snow from cloud ice shows anomalous growth of cloud ice and more than 20% increase of fractional cloud cover, indicating that the lack of the depositional snow growth causes unrealistically large mixing ratio of cloud ice. The experiment excluding the precipitation-radiation interaction displays a significant cooling and drying bias. The analysis of heat and moisture budgets shows that the simulation without the interaction produces more stable upper troposphere and more unstable mid and lower troposphere than does the simulation with the interaction. Thus, the suppressed growth of ice clouds in upper troposphere and stronger radiative cooling in mid and lower troposphere are responsible for the cooling bias, and less evaporation of rain associated with the large-scale subsidence induces the drying in mid and lower troposphere.

  1. Annual Conference on Nuclear and Space Radiation Effects, 15th, University of New Mexico, Albuquerque, N. Mex., July 18-21, 1978, Proceedings

    NASA Technical Reports Server (NTRS)

    Simons, M.

    1978-01-01

    Radiation effects in MOS devices and circuits are considered along with radiation effects in materials, space radiation effects and spacecraft charging, SGEMP, IEMP, EMP, fabrication of radiation-hardened devices, radiation effects in bipolar devices and circuits, simulation, energy deposition, and dosimetry. Attention is given to the rapid anneal of radiation-induced silicon-sapphire interface charge trapping, cosmic ray induced errors in MOS memory cells, a simple model for predicting radiation effects in MOS devices, the response of MNOS capacitors to ionizing radiation at 80 K, trapping effects in irradiated and avalanche-injected MOS capacitors, inelastic interactions of electrons with polystyrene, the photoelectron spectral yields generated by monochromatic soft X radiation, and electron transport in reactor materials.

  2. Assessment of Global Annual Atmospheric Energy Balance from Satellite Observations

    NASA Technical Reports Server (NTRS)

    Lin, Bing; Stackhouse, Paul; Minnis, Patrick; Wielicki, Bruce A.; Hu, Yongxiang; Sun, Wenbo; Fan, Tai-Fang (Alice); Hinkelman, Laura

    2008-01-01

    Global atmospheric energy balance is one of the fundamental processes for the earth's climate system. This study uses currently available satellite data sets of radiative energy at the top of atmosphere (TOA) and surface and latent and sensible heat over oceans for the year 2000 to assess the global annual energy budget. Over land, surface radiation data are used to constrain assimilated results and to force the radiation, turbulent heat, and heat storage into balance due to a lack of observation-based turbulent heat flux estimations. Global annual means of the TOA net radiation obtained from both direct measurements and calculations are close to zero. The net radiative energy fluxes into the surface and the surface latent heat transported into the atmosphere are about 113 and 86 Watts per square meter, respectively. The estimated atmospheric and surface heat imbalances are about -8 9 Watts per square meter, values that are within the uncertainties of surface radiation and sea surface turbulent flux estimates and likely systematic biases in the analyzed observations. The potential significant additional absorption of solar radiation within the atmosphere suggested by previous studies does not appear to be required to balance the energy budget the spurious heat imbalances in the current data are much smaller (about half) than those obtained previously and debated at about a decade ago. Progress in surface radiation and oceanic turbulent heat flux estimations from satellite measurements significantly reduces the bias errors in the observed global energy budgets of the climate system.

  3. Assessment of global annual atmospheric energy balance from satellite observations

    NASA Astrophysics Data System (ADS)

    Lin, Bing; Stackhouse, Paul W.; Minnis, Patrick; Wielicki, Bruce A.; Hu, Yongxiang; Sun, Wenbo; Fan, Tai-Fang; Hinkelman, Laura M.

    2008-08-01

    Global atmospheric energy balance is one of the fundamental processes for the earth's climate system. This study uses currently available satellite data sets of radiative energy at the top of atmosphere (TOA) and surface as well as latent and sensible heat over the oceans for the year 2000 to assess the global annual energy budget. Over land, surface radiation data are used to constrain assimilated results and to force the radiation, turbulent heat, and heat storage into balance due to a lack of observation-based turbulent heat flux estimates. Global annual means of the TOA net radiation obtained from both satellite direct measurements and calculations are close to zero. The net radiative energy fluxes into the surface and the surface latent heat transported into the atmosphere are about 113 and 86 W/m2, respectively. The estimated atmospheric and surface heat imbalances are about -8 and 9 W/m2, respectively, values that are within the uncertainties of surface radiation and sea surface turbulent flux estimates and the likely systematic biases in the analyzed observations. The potential significant additional absorption of solar radiation within the atmosphere suggested by previous studies does not appear to be required to balance the energy budget: the spurious heat imbalances in the current data are much smaller (about half) than those obtained previously and debated about a decade ago. Progress in surface radiation and oceanic turbulent heat flux estimations from satellite measurements has significantly reduced the bias errors in the observed global energy budgets of the climate system.

  4. Development of an intelligent grinding wheel for in-process monitoring of ceramic grinding. Semi-annual report {number_sign}3

    SciTech Connect

    Malkin, S.; Gao, R.; Guo, C.; Varghese, B.; Pathare, S.

    1998-03-26

    This is the third semi-annual report for the project. The overall objective of this project is to develop sensor-integrated intelligent diamond wheels for grinding of ceramics. Such wheels will be smart enough to monitor and supervise both the wheel preparation and grinding processes without the need to instrument the machine tool. Intelligent wheels will utilize re-useable cores integrated with sensors: to measure the acoustic emission (AE) and grinding force. Signals from the sensors will be transmitted from a rotating wheel to a receiver by telemetry. Wheels will be trained to recognize distinct characteristics associated with truing, dressing and grinding. The technical progress is summarized in this report.

  5. Radiation processing of Nylon 6 by e-beam for improved properties and performance

    NASA Astrophysics Data System (ADS)

    Pramanik, N. K.; Haldar, R. S.; Bhardwaj, Y. K.; Sabharwal, S.; Niyogi, U. K.; Khandal, R. K.

    2009-03-01

    Percent water absorption of Nylon 6 was reduced substantially when irradiated by e-beam radiation in presence of triallyl isocyanurate. Hardness, tensile strength, flexural strength, and impact resistance of Nylon 6 were also improved with the dose of e-beam radiation. Improvement of mechanical properties and reduction of water absorption were due to the cross-linking of polyamide molecules in the presence of high-energy radiation. Increase of cross-linking with increasing radiation dose was verified by the increase of gel content at higher doses.

  6. [Radiation therapy and cardiac pacemakers].

    PubMed

    Serafim, P; Fonseca, G; Oliveira, A; Fernandes, T

    1999-05-01

    The number of patients with cardiac pacemakers submitted annually to radiation therapy is increasing. Radiation therapy causes interference in the normal functioning processes, directly by chemical changes in the structure of the device and also by electromagnetic disturbances generated in the process of treatment. The changes in the technology used in the manufacture of cardiac pacemakers after the 70's, with the introduction of complementary metal-oxide semi-conductors (CMOS) in the circuits, drastically increased the chance of dangerous interference in the normal function of cardiac pacemakers occurring when in contact with an ionizing radiation source. The authors briefly describe the mechanisms underlying the radio-induced damage usually observed. A review of the literature on this issue is made and solutions are pointed out to perform safe radiation therapy and minimize the risk of device malfunction. PMID:10418264

  7. [Retrospective Cytogenetic Dose Evaluation. II. Computer Data Processing in Persons Irradiated in Different Radiation Accidents].

    PubMed

    Nugis, V Yu; Khvostunov, I K; Goloub, E V; Kozlova, M G; Nadejinal, N M; Galstian, I A

    2015-01-01

    The method for retrospective dose assessment based on the analysis of cell distribution by the number of dicentrics and unstable aberrations using a special computer program was earlier developed based on the data about the persons irradiated as a result of the accident at the Chernobyl nuclear power plant. This method was applied for the same purpose for data processing of repeated cytogenetic studies of the patients exposed to γ-, γ-β- or γ-neutron radiation in various situations. As a whole, this group was followed up in more distant periods (17-50 years) after exposure than Chernobyl patients (up to 25 years). The use for retrospective dose assessment of the multiple regression equations obtained for the Chernobyl cohort showed that the equation, which includes computer recovered estimate of the dose and the time elapsed after irradiation, was generally unsatisfactory (r = 0.069 at p = 0.599). Similar equations with recovered estimate of the dose and frequency of abnormal chromosomes in a distant period or with all three parameters as variables gave better results (r = 0.686 at p = 0.000000001 and r = 0.542 at p = 0.000008, respectively). PMID:26863777

  8. Non-radiative processes in protonated diazines, pyrimidine bases and an aromatic azine.

    PubMed

    Pino, Gustavo A; Feraud, Géraldine; Broquier, Michel; Grégoire, Gilles; Soorkia, Satchin; Dedonder, Claude; Jouvet, Christophe

    2016-07-27

    The excited state lifetimes of DNA bases are often very short due to very efficient non-radiative processes assigned to the ππ*-nπ* coupling. A set of protonated aromatic diazine molecules (pyridazine, pyrimidine and pyrazine C4H5N2(+)) and protonated pyrimidine DNA bases (cytosine, uracil and thymine), as well as the protonated pyridine (C5H6N(+)), have been investigated. For all these molecules except one tautomer of protonated uracil (enol-keto), electronic spectroscopy exhibits vibrational line broadening. Excited state geometry optimization at the CC2 level has been conducted to find out whether the excited state lifetimes measured from line broadening can be correlated to the calculated ordering of the ππ* and nπ* states and the ππ*-nπ* energy gap. The short lifetimes, observed when one nitrogen atom of the ring is not protonated, can be rationalized by relaxation of the ππ* state to the nπ* state or directly to the electronic ground state through ring puckering. PMID:27110833

  9. Simulations of microphysical, radiative, and dynamical processes in a continental-scale forest fire smoke plume

    NASA Technical Reports Server (NTRS)

    Westphal, Douglas L.; Toon, Owen B.

    1991-01-01

    The impact of a large forest fire smoke plume on atmospheric processes is studied through a numerical model of meteorology, aerosols, and radiative transfer. The simulated smoke optical depths at 0.63-micron wavelength are in agreement with analyses of satellite data and show values as high as 1.8. The smoke has an albedo of 35 percent, or more than double the clear-sky value, and cools the surface by as much as 5 K. An imaginary refractive index, n sub im, of 0.01 yields results which closely match the observed cooling, single scattering albedo, and the Angstrom wavelength exponent. An n exp im of 0.1, typical of smoke from urban fires, produces 9 K cooling. Coagulation causes the geometric mean radius by number to increase from the initial value of 0.08 micron to a final value of 0.15 micron, while the specific extinction and absorption increase by 40 and 25 percent, respectively.

  10. Simulation of energy-dependent electron diffusion processes in the Earth's outer radiation belt

    NASA Astrophysics Data System (ADS)

    Ma, Q.; Li, W.; Thorne, R. M.; Nishimura, Y.; Zhang, X.-J.; Reeves, G. D.; Kletzing, C. A.; Kurth, W. S.; Hospodarsky, G. B.; Henderson, M. G.; Spence, H. E.; Baker, D. N.; Blake, J. B.; Fennell, J. F.; Angelopoulos, V.

    2016-05-01

    The radial and local diffusion processes induced by various plasma waves govern the highly energetic electron dynamics in the Earth's radiation belts, causing distinct characteristics in electron distributions at various energies. In this study, we present our simulation results of the energetic electron evolution during a geomagnetic storm using the University of California, Los Angeles 3-D diffusion code. Following the plasma sheet electron injections, the electrons at different energy bands detected by the Magnetic Electron Ion Spectrometer (MagEIS) and Relativistic Electron Proton Telescope (REPT) instruments on board the Van Allen Probes exhibit a rapid enhancement followed by a slow diffusive movement in differential energy fluxes, and the radial extent to which electrons can penetrate into depends on energy with closer penetration toward the Earth at lower energies than higher energies. We incorporate radial diffusion, local acceleration, and loss processes due to whistler mode wave observations to perform a 3-D diffusion simulation. Our simulation results demonstrate that chorus waves cause electron flux increase by more than 1 order of magnitude during the first 18 h, and the subsequent radial extents of the energetic electrons during the storm recovery phase are determined by the coupled radial diffusion and the pitch angle scattering by EMIC waves and plasmaspheric hiss. The radial diffusion caused by ULF waves and local plasma wave scattering are energy dependent, which lead to the observed electron flux variations with energy dependences. This study suggests that plasma wave distributions in the inner magnetosphere are crucial for the energy-dependent intrusions of several hundred keV to several MeV electrons.

  11. Measurements and simulation of the radiation build-up process in a prebunched free-electron maser oscillator

    SciTech Connect

    Gilutin, L.; Pinhasi, Y.; Cohen, M.

    1995-12-31

    Numerical studies of the radiation buildup process in a prebunched free-electron maser oscillator (FEM), were carried out at Tel-Aviv University (TAU) and at the University of Maryland (UMD), and compared to the experimental measurements taken on the prebunched beam FEM experiments in TAU. We present measurements of the temporal evolution of radiation excited from noise until a steady-state operation is established. The evolution of the spectral characteristics of the radiation was investigated using the data collected by a fast digitizing scope, which recorded the IF signal obtained from heterodyning the laser radiation with a stable local oscillator. The mode competition process was observed. The experimental results were compared to analytical calculations of the spontaneous emission power and small-signal gain. Nonlinear {open_quote}amplifier{close_quote} simulation codes were employed for calculation of the extraction efficiency and saturation power. Multi-frequency simulations of the mode competition process were carried out using simulation (MALT ID) code, which is based on a space-time one-dimensional model of a free-electron laser oscillator. Conditions for establishment of single-(longitudinal) mode operation were identified and compared to the experimental measurements. Prebunching of the e-beam current permits external interference in the mode competition and coherence build-up process. We found experimentally and confirmed numerically that prebunching can determine the frequency of oscillation if the e-beam is injected with a sufficient bunching power, and shortens the oscillation buildup and coherence establishment time.

  12. 1992 IEEE Annual Conference on Nuclear and Space Radiation Effects, 29th, New Orleans, LA, July 13-17, 1992, Proceedings

    NASA Technical Reports Server (NTRS)

    Van Vonno, Nick W. (Editor)

    1992-01-01

    The papers presented in this volume provide an overview of recent theoretical and experimental research related to nuclear and space radiation effects. Topics dicussed include single event phenomena, radiation effects in particle detectors and associated electronics for accelerators, spacecraft charging, and space environments and effects. The discussion also covers hardness assurance and testing techniques, electromagnetic effects, radiation effects in devices and integrated circuits, dosimetry and radiation facilities, isolation techniques, and basic mechanisms.

  13. SSC environmental radiation shielding

    SciTech Connect

    Jackson, J.D.

    1987-07-01

    The environmental radiation shielding requirements of the SSC have been evaluated using currently available computational tools that incorporate the well known processes of energy loss and degradation of high energy particles into Monte Carlo computer codes. These tools permit determination of isodose contours in the matter surrounding a source point and therefore the specification of minimum thicknesses or extents of shielding in order to assure annual dose equivalents less than some specified design amount. For the general public the annual dose equivalent specified in the design is 10 millirem, small compared to the dose from naturally occurring radiation. The types of radiation fall into two classes for the purposes of shielding determinations-hadrons and muons. The sources of radiation at the SSC of concern for the surrounding environment are the interaction regions, the specially designed beam dumps into which the beams are dumped from time to time, and beam clean-up regions where stops remove the beam halo in order to reduce experimental backgrounds. A final, unlikely source of radiation considered is the accidental loss of the full beam at some point around the ring. Conservative choices of a luminosity of 10{sup 34} cm{sup {minus}2}s{sup {minus}1} and a beam current three times design have been made in calculating the required shielding and boundaries of the facility. In addition to determination of minimum distances for the annual dose equivalents, the question of possible radioactivity produced in nearby wells or in municipal water supplies is addressed. The designed shielding distances and beam dumps are such that the induced radioactivity in ground water is safely smaller than the levels permitted by EPA and international agencies.

  14. Neutron and gamma radiation shielding material, structure, and process of making structure

    DOEpatents

    Hondorp, Hugh L.

    1984-01-01

    The present invention is directed to a novel neutron and gamma radiation elding material consisting of 95 to 97 percent by weight SiO.sub.2 and 5 to 3 percent by weight sodium silicate. In addition, the method of using this composition to provide a continuous neutron and gamma radiation shielding structure is disclosed.

  15. Radiative-dynamical and microphysical processes of thin cirrus clouds controlling humidity of air entering the stratosphere

    NASA Astrophysics Data System (ADS)

    Dinh, Tra; Fueglistaler, Stephan

    2016-04-01

    Thin cirrus clouds in the tropical tropopause layer (TTL) are of great interest due to their role in the control of water vapor and temperature in the TTL. Previous research on TTL cirrus clouds has focussed mainly on microphysical processes, specifically the ice nucleation mechanism and dehydration efficiency. Here, we use a cloud resolving model to analyse the sensitivity of TTL cirrus characteristics and impacts with respect to microphysical and radiative processes. A steady-state TTL cirrus cloud field is obtained in the model forced with dynamical conditions typical for the TTL (2-dimensional setup with a Kelvin-wave temperature perturbation). Our model results show that the dehydration efficiency (as given by the domain average relative humidity in the layer of cloud occurrence) is relatively insensitive to the ice nucleation mechanism, i.e. homogeneous versus heterogeneous nucleation. Rather, TTL cirrus affect the water vapor entering the stratosphere via an indirect effect associated with the cloud radiative heating and dynamics. Resolving the cloud radiative heating and the radiatively induced circulations approximately doubles the domain average ice mass. The cloud radiative heating is proportional to the domain average ice mass, and the observed increase in domain average ice mass induces a domain average temperature increase of a few Kelvin. The corresponding increase in water vapor entering the stratosphere is estimated to be about 30 to 40%.

  16. 1991 IEEE Annual Conference on Nuclear and Space Radiation Effects, 28th, San Diego, CA, July 15-19, 1991, Proceedings

    NASA Technical Reports Server (NTRS)

    Millward, Douglas G. (Editor)

    1991-01-01

    Various papers on nuclear science are presented. The general topics addressed are: basic mechanisms of radiation effects, dosimetry and energy-dependent effects, isolation technologies, device radiation response and hardening, microcircuit radiation response and hardening, single-event phenomena, hardness assurance and testing techniques, spacecraft charging, space environments and effects.

  17. Direct satellite observations on bremsstrahlung radiation as a technique to investigate its role in meteorological processes

    NASA Technical Reports Server (NTRS)

    Johnson, R. G.; Imhof, W. L.

    1975-01-01

    It was suggested that bremsstrahlung radiation associated with strong auroras (in turn associated with geomagnetic disturbances) may cause increased ionization near the 300-millibar level, which, in turn, leads to the formation of cirrus clouds. These clouds could modify the outgoing black body radiation rates and influence weather patterns. The first satellite observations on bremsstrahlung radiation produced in the atmosphere by precipitating energetic electrons are discussed. This type of observation affords the possibility of directly monitoring the bremsstrahlung energy input to the lower atmosphere over large segments of earth and at frequent intervals. Detailed measurements on the spatial and energy distributions of the bremsstrahlung radiation are feasible with present techniques, and satellite data on widespread bremsstrahlung events are presented and discussed. From comparison of the ion production rates from cosmic rays with those calculated from bremsstrahlung from precipitating energetic electrons, it is concluded that bremsstrahlung radiation is a negligible contributor to the ionization near the 300-millibar level.

  18. [Studies of the repair of radiation-induced genetic damage in Drosophila]. Annual progress report, October 1, 1988--June 1, 1989

    SciTech Connect

    1989-12-31

    The primary goal of this study is to achieve a more thorough understanding of the mechanisms employed by higher organisms to repair DNA damage induced by both ionizing and nonionizing radiation. These studies are also contributing to an improved understanding of the processes of mutagenesis and carcinogenesis in higher eukaryotes. The studies employ Drosophila as a model organism for investigating repair functions that are common to all higher eukaryotes. Drosophila was chosen in the early phases of this study primarily because of the ease with which one can isolate and characterize repair-deficient mutants in a metazoan organism. The laboratory has gone on to investigate the metabolic defects of such mutants while others have performed complementary genetic and cytogenetic studies which relate DNA repair processes to mutagenesis and chromosome stability. The repair studies have exploited the capacity to introduce mutant Drosophila cells into tissue culture and thereby compare repair defects directly with those of homologous human disorders. Researchers are currently employing recombinant DNA technology to investigate the mechanisms of the DNA repair pathways defined by those mutants.

  19. Update on scribe-cleave-passivate (SCP) slim edge technology for silicon sensors: Automated processing and radiation resistance

    NASA Astrophysics Data System (ADS)

    Fadeyev, V.; Ely, S.; Galloway, Z.; Ngo, J.; Parker, C.; Sadrozinski, H. F.-W.; Christophersen, M.; Phlips, B. F.; Pellegrini, G.; Rafi, J. M.; Quirion, D.; Dalla Betta, G.-F.; Boscardin, M.; Casse, G.; Gorelov, I.; Hoeferkamp, M.; Metcalfe, J.; Seidel, S.; Gaubas, E.; Ceponis, T.; Vaitkus, J. V.

    2014-11-01

    We pursue scribe-cleave-passivate (SCP) technology for making "slim edge" sensors. The goal is to reduce the inactive region at the periphery of the devices while maintaining their performance. In this paper we report on two aspects of the current efforts. The first one involves fabrication options for mass production. We describe the automated cleaving tests and a simplified version of SCP post-processing of n-type devices. Another aspect is the radiation resistance of the passivation. We report on the radiation tests of n- and p-type devices with protons and neutrons.

  20. Microstructural processes in irradiated materials

    NASA Astrophysics Data System (ADS)

    Byun, Thak Sang; Morgan, Dane; Jiao, Zhijie; Almer, Jonathan; Brown, Donald

    2016-04-01

    These proceedings contain the papers presented at two symposia, the Microstructural Processes in Irradiated Materials (MPIM) and Characterization of Nuclear Reactor Materials and Components with Neutron and Synchrotron Radiation, held in the TMS 2015, 144th Annual Meeting & Exhibition at Walt Disney World, Orlando, Florida, USA on March 15-19, 2015.

  1. Process and pattern in cichlid radiations - inferences for understanding unusually high rates of evolutionary diversification.

    PubMed

    Seehausen, Ole

    2015-07-01

    The cichlid fish radiations in the African Great Lakes differ from all other known cases of rapid speciation in vertebrates by their spectacular trophic diversity and richness of sympatric species, comparable to the most rapid angiosperm radiations. I review factors that may have facilitated these radiations and compare these with insights from recent work on plant radiations. Work to date suggests that it was a coincidence of ecological opportunity, intrinsic ecological versatility and genomic flexibility, rapidly evolving behavioral mate choice and large amounts of standing genetic variation that permitted these spectacular fish radiations. I propose that spatially orthogonal gradients in the fit of phenotypes to the environment facilitate speciation because they allow colonization of alternative fitness peaks during clinal speciation despite local disruptive selection. Such gradients are manifold in lakes because of the interaction of water depth as an omnipresent third spatial dimension with other fitness-relevant variables. I introduce a conceptual model of adaptive radiation that integrates these elements and discuss its applicability to, and predictions for, plant radiations. PMID:25983053

  2. Parallel processing approach for radiative heat transfer prediction in participating media

    NASA Astrophysics Data System (ADS)

    Saltiel, C.; Naraghi, M. H. N.

    1993-10-01

    Numerical analysis of radiative transfer in participating media can be very complex. Computer simulations of practical situations often require both large computer memory and long calculation times. The use of massively parallel machines has proven very effective in simulating large complex systems. This technical note presents a unified matrix formulation for node-to-node-based radiative exchange in isotropically scattering homogeneous media using the discrete exchange factor (DEF) method. Computational implementation is compared between serial and parallel computing machines. The results demonstrate that parallel computing has the potential for changing the nature of radiative transfer calculations. Parallel computing allows for faster, more manageable calculations; it is especially effective for nonlinear problems.

  3. Atmospheric radiation

    SciTech Connect

    Harshvardhan, M.R. )

    1991-01-01

    Studies of atmospheric radiative processes are summarized for the period 1987-1990. Topics discussed include radiation modeling; clouds and radiation; radiative effects in dynamics and climate; radiation budget and aerosol effects; and gaseous absorption, particulate scattering and surface reflection. It is concluded that the key developments of the period are a defining of the radiative forcing to the climate system by trace gases and clouds, the recognition that cloud microphysics and morphology need to be incorporated not only into radiation models but also climate models, and the isolation of a few important unsolved theoretical problems in atmospheric radiation.

  4. A new highly automated sputter equipment for in situ investigation of deposition processes with synchrotron radiation.

    PubMed

    Döhrmann, Ralph; Botta, Stephan; Buffet, Adeline; Santoro, Gonzalo; Schlage, Kai; Schwartzkopf, Matthias; Bommel, Sebastian; Risch, Johannes F H; Mannweiler, Roman; Brunner, Simon; Metwalli, Ezzeldin; Müller-Buschbaum, Peter; Roth, Stephan V

    2013-04-01

    HASE (Highly Automated Sputter Equipment) is a new mobile setup developed to investigate deposition processes with synchrotron radiation. HASE is based on an ultra-high vacuum sputter deposition chamber equipped with an in-vacuum sample pick-and-place robot. This enables a fast and reliable sample change without breaking the vacuum conditions and helps to save valuable measurement time, which is required for experiments at synchrotron sources like PETRA III at DESY. An advantageous arrangement of several sputter guns, mounted on a rotative flange, gives the possibility to sputter under different deposition angles or to sputter different materials on the same substrate. The chamber is also equipped with a modular sample stage, which allows for the integration of different sample environments, such as a sample heating and cooling device. The design of HASE is unique in the flexibility. The combination of several different sputtering methods like standard deposition, glancing angle deposition, and high pressure sputter deposition combined with heating and cooling possibilities of the sample, the large exit windows, and the degree of automation facilitate many different grazing incidence X-ray scattering experiments, such as grazing incidence small and wide angle X-ray scattering, in one setup. In this paper we describe in detail the design and the performance of the new equipment and present the installation of the HASE apparatus at the Micro and Nano focus X-ray Scattering beamline (MiNaXS) at PETRA III. Furthermore, we describe the measurement options and present some selected results. The HASE setup has been successfully commissioned and is now available for users. PMID:23635203

  5. Supernova Emulators: Connecting Massively Parallel SN Ia Radiative Transfer Simulations to Data with Gaussian Processes

    NASA Astrophysics Data System (ADS)

    Goldstein, Daniel; Thomas, Rollin; Kasen, Daniel

    2015-01-01

    Collaboration between the type Ia supernova (SN Ia) modeling and observation communities hinges on our ability to directly connect simulations to data. Here we introduce supernova emulation, a method for facilitating such a connection. Emulation allows us to instantaneously predict the observables (light curves, spectra, spectral time series) generated by arbitrary SN Ia radiative transfer simulations, with estimates of prediction error. Emulators learn the mapping between physically meaningful simulation inputs and the resulting synthetic observables from a training set of simulation input-output pairs. In our emulation framework, we model PCA-decomposed representations of simulated observables as an ensemble of Gaussian Processes. As a proof of concept, we train a bolometric light curve (BLC) emulator on a grid of 400 simulation inputs and BLCs synthesized with the publicly available, gray, time-dependent Monte Carlo expanding atmospheres code, SMOKE. We emulate SMOKE simulations evaluated at a set of 100 out-of-sample input parameters, and achieve excellent agreement between the emulator predictions and the simulated BLCs. In addition to predicting simulation outputs, emulators allow us to infer the regions of simulation input parameter space that correspond to observed SN Ia light curves and spectra. We present a Bayesian framework for solving this inverse problem using Markov Chain Monte Carlo sampling. We fit published bolometric light curves with our emulator and obtain reconstructed masses (nickel mass, total ejecta mass) in agreement with reconstructions from semi-analytic models. We discuss applications of emulation to supernova cosmology and physics, including how emulators can be used to identify and quantify astrophysical sources of systematic error affecting SNe Ia as distance indicators for cosmology.

  6. A new highly automated sputter equipment for in situ investigation of deposition processes with synchrotron radiation

    SciTech Connect

    Doehrmann, Ralph; Botta, Stephan; Buffet, Adeline; Santoro, Gonzalo; Schlage, Kai; Schwartzkopf, Matthias; Risch, Johannes F. H.; Mannweiler, Roman; Roth, Stephan V.; Bommel, Sebastian; Brunner, Simon; Metwalli, Ezzeldin; Mueller-Buschbaum, Peter

    2013-04-15

    HASE (Highly Automated Sputter Equipment) is a new mobile setup developed to investigate deposition processes with synchrotron radiation. HASE is based on an ultra-high vacuum sputter deposition chamber equipped with an in-vacuum sample pick-and-place robot. This enables a fast and reliable sample change without breaking the vacuum conditions and helps to save valuable measurement time, which is required for experiments at synchrotron sources like PETRA III at DESY. An advantageous arrangement of several sputter guns, mounted on a rotative flange, gives the possibility to sputter under different deposition angles or to sputter different materials on the same substrate. The chamber is also equipped with a modular sample stage, which allows for the integration of different sample environments, such as a sample heating and cooling device. The design of HASE is unique in the flexibility. The combination of several different sputtering methods like standard deposition, glancing angle deposition, and high pressure sputter deposition combined with heating and cooling possibil-ities of the sample, the large exit windows, and the degree of automation facilitate many different grazing incidence X-ray scattering experiments, such as grazing incidence small and wide angle X-ray scattering, in one setup. In this paper we describe in detail the design and the performance of the new equipment and present the installation of the HASE apparatus at the Micro and Nano focus X-ray Scattering beamline (MiNaXS) at PETRA III. Furthermore, we describe the measurement options and present some selected results. The HASE setup has been successfully commissioned and is now available for users.

  7. Annual Conference on Nuclear and Space Radiation Effects, 18th, University of Washington, Seattle, WA, July 21-24, 1981, Proceedings

    NASA Technical Reports Server (NTRS)

    Tasca, D. M.

    1981-01-01

    Single event upset phenomena are discussed, taking into account cosmic ray induced errors in IIL microprocessors and logic devices, single event upsets in NMOS microprocessors, a prediction model for bipolar RAMs in a high energy ion/proton environment, the search for neutron-induced hard errors in VLSI structures, soft errors due to protons in the radiation belt, and the use of an ion microbeam to study single event upsets in microcircuits. Basic mechanisms in materials and devices are examined, giving attention to gamma induced noise in CCD's, the annealing of MOS capacitors, an analysis of photobleaching techniques for the radiation hardening of fiber optic data links, a hardened field insulator, the simulation of radiation damage in solids, and the manufacturing of radiation resistant optical fibers. Energy deposition and dosimetry is considered along with SGEMP/IEMP, radiation effects in devices, space radiation effects and spacecraft charging, EMP/SREMP, and aspects of fabrication, testing, and hardness assurance.

  8. Statistical characteristics of cloud variability. Part 2: Implication for parameterizations of microphysical and radiative transfer processes in climate models

    SciTech Connect

    Huang, Dong; Liu, Yangang

    2014-09-17

    The effects of subgrid cloud variability on grid-average microphysical rates and radiative fluxes are examined by use of long-term retrieval products at the Tropical West Pacific, Southern Great Plains, and North Slope of Alaska sites of the Department of Energy's Atmospheric Radiation Measurement program. Four commonly used distribution functions, the truncated Gaussian, Gamma, lognormal, and Weibull distributions, are constrained to have the same mean and standard deviation as observed cloud liquid water content. The probability density functions are then used to upscale relevant physical processes to obtain grid-average process rates. It is found that the truncated Gaussian representation results in up to 30% mean bias in autoconversion rate, whereas the mean bias for the lognormal representation is about 10%. The Gamma and Weibull distribution function performs the best for the grid-average autoconversion rate with the mean relative bias less than 5%. For radiative fluxes, the lognormal and truncated Gaussian representations perform better than the Gamma and Weibull representations. The results show that the optimal choice of subgrid cloud distribution function depends on the nonlinearity of the process of interest, and thus, there is no single distribution function that works best for all parameterizations. Examination of the scale (window size) dependence of the mean bias indicates that the bias in grid-average process rates monotonically increases with increasing window sizes, suggesting the increasing importance of subgrid variability with increasing grid sizes.

  9. Improvement of Moist and Radiative Processes in Highly Parallel Atmospheric General Circulation Models: Validation and Development

    SciTech Connect

    Frank, William M.; Hack, James J.; Kiehl, Jeffrey T.

    1997-02-24

    Research on designing an integrated moist process parameterization package was carried. This work began with a study that coupled an ensemble of cloud models to a boundary layer model to examine the feasibility of such a methodology for linking boundary layer and cumulus parameterization schemes. The approach proved feasible, prompting research to design and evaluate a coupled parameterization package for GCMS. This research contributed to the development of an Integrated Cumulus Ensemble-Turbulence (ICET) parameterization package. This package incorporates a higher-order turbulence boundary layer that feeds information concerning updraft properties and the variances of temperature and water vapor to the cloud parameterizations. The cumulus ensemble model has been developed, and initial sensitivity tests have been performed in the single column model (SCM) version of CCM2. It is currently being coupled to a convective wake/gust front model. The major function of the convective wake/gust front model is to simulate the partitioning of the boundary layer into disturbed and undisturbed regions. A second function of this model is to predict the nonlinear enhancement of surface to air sensible heat and moisture fluxes that occur in convective regimes due to correlations between winds and anomalously cold, dry air from downdrafts in the gust front region. The third function of the convective wake/gust front model is to predict the amount of undisturbed boundary layer air lifted by the leading edge of the wake and the height to which this air is lifted. The development of the wake/gust front model has been completed, and it has done well in initial testing as a stand-alone component. The current task, to be completed by the end of the funding period, is to tie the wake model to a cumulus ensemble model and to install both components into the single column model version of CCM3 for evaluation. Another area of parametrization research has been focused on the representation

  10. Development and validation of a black carbon mixing state resolved three-dimensional model: Aging processes and radiative impact

    NASA Astrophysics Data System (ADS)

    Matsui, H.; Koike, M.; Kondo, Y.; Moteki, N.; Fast, J. D.; Zaveri, R. A.

    2013-03-01

    A new two-dimensional aerosol bin scheme, which resolves both aerosol size and black carbon (BC) mixing state for BC aging processes (e.g., condensation and coagulation) with 12 size × 10 mixing state bins, has been developed and implemented into the WRF-chem model (MS-resolved WRF-chem). The mixing state of BC simulated by this model is compared with direct measurements over the East Asian region in spring 2009. Model simulations generally reproduce the observed features of the BC mixing state, such as the size-dependent number fractions of BC-containing and BC-free particles and the coating thickness of BC-containing particles. This result shows that the model can simulate realistic BC mixing states in the atmosphere if condensation and coagulation processes are calculated explicitly with the detailed treatment of BC mixing state. Sensitivity simulations show that the condensation process is dominant for the growth of thinly coated BC particles, while the coagulation process is necessary to produce thickly coated BC particles. Off-line optical and radiative calculations assuming an average mixing state for each size bin show that the domain- and period-averaged absorption coefficient and heating rate by aerosols are overestimated by 30-40% in the boundary layer, compared with a benchmark simulation with the detailed treatment of mixing state. The absolute value of aerosol radiative forcing is also overestimated (10%, 3 W m-2) at the surface. However, these overestimations are reduced considerably when all the parameters (including mass and number concentration) are calculated with the simple treatment of mixing state. This is because the overestimation of radiative parameters due to higher absorption efficiency (compared with the benchmark simulation) is largely canceled by the underestimation of BC concentrations due to efficient wet removal processes. The overall errors in radiative forcing can be much smaller because of this cancellation, but for the wrong

  11. A novel energy-efficient plasma chemical process for the destruction of volatile toxic compounds. 1997 annual progress report

    SciTech Connect

    Pinnaduwage, L.A.; Ma, C.Y.L.

    1997-09-01

    'The objective of this research program is to develop new plasma chemical processes for the destruction of volatile toxic compounds (VTCs) in contaminated air streams where the contamination levels are below a few percent. The authors plan to exploit the large cross sections associated with dissociative electron attachment to highly excited molecular states. Such highly excited states are to be populated in glow discharges via excitation transfer from high- lying, metastable states of rare gases. Basic knowledge of the excitation transfer processes and the electron attachment processes are crucial to the development of the proposed techniques, and these processes will be studied in detail.'

  12. Hazards Control Department annual technology review, 1987

    SciTech Connect

    Griffith, R.V.; Anderson, K.J.

    1988-07-01

    This document describes some of the research performed in the LLNL Hazards Control Department from October 1986 to September 1987. The sections in the Annual report cover scientific concerns in the areas of Health Physics, Industrial Hygiene, Industrial Safety, Aerosol Science, Resource Management, Dosimetry and Radiation Physics, Criticality Safety, and Fire Science. For a broader overview of the types of work performed in the Hazards Control Department, we have also compiled a selection of abstracts of recent publications by Hazards Control employees. Individual reports are processed separately for the data base.

  13. Impact of increasing Ultraviolet-B (UV-B) radiation on photosynthetic processes.

    PubMed

    Kataria, Sunita; Jajoo, Anjana; Guruprasad, Kadur N

    2014-08-01

    Increased UV-B radiation on the earth's surface due to depletion of stratospheric ozone layer is one of the changes of current climate-change pattern. The deleterious effects of UV-B radiation on photosynthesis and photosynthetic productivity of plants are reviewed. Perusal of relevant literature reveals that UV-B radiation inflicts damage to the photosynthetic apparatus of green plants at multiple sites. The sites of damage include oxygen evolving complex, D1/D2 reaction center proteins and other components on the donor and acceptor sides of PS II. The radiation inactivates light harvesting complex II and alters gene expression for synthesis of PS II reaction center proteins. Mn cluster of water oxidation complex is the most important primary target of UV-B stress whereas D1 and D2 proteins, quinone molecules and cytochrome b are the subsequent targets of UV-B. In addition, photosynthetic carbon reduction is also sensitive to UV-B radiation which has a direct effect on the activity and content of Rubisco. Some indirect effects of UV-B radiation include changes in photosynthetic pigments, stomatal conductance and leaf and canopy morphology. The failure of protective mechanisms makes PS II further vulnerable to the UV-B radiation. Reactive oxygen species are involved in UV-B induced responses in plants, both as signaling and damaging agents. Exclusion of ambient UV components under field conditions results in the enhancement of the rate of photosynthesis, PS II efficiency and subsequently increases the biomass accumulation and crop yield. It is concluded that predicted future increase in UV-B irradiation will have significant impact on the photosynthetic efficiency and the productivity of higher plants. PMID:24725638

  14. The sensitivity of convective aggregation to diabatic processes in idealized radiative-convective equilibrium simulations

    NASA Astrophysics Data System (ADS)

    Holloway, C. E.; Woolnough, S. J.

    2016-03-01

    Idealized explicit convection simulations of the Met Office Unified Model exhibit spontaneous self-aggregation in radiative-convective equilibrium, as seen in other models in previous studies. This self-aggregation is linked to feedbacks between radiation, surface fluxes, and convection, and the organization is intimately related to the evolution of the column water vapor field. Analysis of the budget of the spatial variance of column-integrated frozen moist static energy (MSE), following Wing and Emanuel (2014), reveals that the direct radiative feedback (including significant cloud longwave effects) is dominant in both the initial development of self-aggregation and the maintenance of an aggregated state. A low-level circulation at intermediate stages of aggregation does appear to transport MSE from drier to moister regions, but this circulation is mostly balanced by other advective effects of opposite sign and is forced by horizontal anomalies of convective heating (not radiation). Sensitivity studies with either fixed prescribed radiative cooling, fixed prescribed surface fluxes, or both do not show full self-aggregation from homogeneous initial conditions, though fixed surface fluxes do not disaggregate an initialized aggregated state. A sensitivity study in which rain evaporation is turned off shows more rapid self-aggregation, while a run with this change plus fixed radiative cooling still shows strong self-aggregation, supporting a "moisture-memory" effect found in Muller and Bony (2015). Interestingly, self-aggregation occurs even in simulations with sea surface temperatures (SSTs) of 295 and 290 K, with direct radiative feedbacks dominating the budget of MSE variance, in contrast to results in some previous studies.

  15. 8. annual international energy week conference and exhibition: Conference papers. Book 2: Pipelines, terminals and storage; Processing and refining

    SciTech Connect

    1997-05-01

    This volume contains 37 papers arranged in the following topical sections: Pipeline integrity; Risk management and assessment; Pipeline simulation; Nondestructive examination; New technology and research; Internal corrosion; Cathodic protection; Operational pigging; Pipeline and leak detection; Intelligent pigging; Above ground storage tanks; Gasification; Custom catalyst manufacturing; Petrochemicals; and Gas processing. Papers have been processed separately for inclusion on the database.

  16. Synchrotron radiation as a light source in confocal microscopy of biological processes

    NASA Astrophysics Data System (ADS)

    Gerritsen, Hans C.; van der Oord, C. J. R.; Levine, Yehudi K.; Munro, Ian H.; Myring, Wendy J.; Shaw, D. A.; Rommerts, Fokko F.

    1992-04-01

    A novel confocal microscope is presented using the Daresbury Synchrotron Radiation source as its light source. The broad spectrum of synchrotron radiation in combination with the UV compatible microscope allows the extension of confocal microscopy from the visible to the UV region down to about 200 nm. It is envisaged that structures separated by about 70 nm can be resolved at a wavelength of 200 nm. In addition, the tunability of synchrotron radiation affords the selective excitation of any specific fluorescent molecule at the maximum of the absorption band. This avoids the restriction of working at fixed laser lines. A further advantage of using synchrotron radiation is the realization of multiwavelength excitation. Test results using laser systems in the visible and in the UV are presented. Fluorescence images of test targets using UV excitation reveal the superior resolution of the microscope. Furthermore, images of Leydig cells incubated with a fluorescent cholesterol derivative whose maximum of absorption is at 325 nm are shown. These images cannot be produced by conventional confocal laser microscopes. Finally, promising preliminary results obtained with synchrotron radiation are presented.

  17. Highly biocompatible, nanocrystalline hydroxyapatite synthesized in a solvothermal process driven by high energy density microwave radiation.

    PubMed

    Smolen, Dariusz; Chudoba, Tadeusz; Malka, Iwona; Kedzierska, Aleksandra; Lojkowski, Witold; Swieszkowski, Wojciech; Kurzydlowski, Krzysztof Jan; Kolodziejczyk-Mierzynska, Małgorzata; Lewandowska-Szumiel, Małgorzata

    2013-01-01

    A microwave, solvothermal synthesis of highly biocompatible hydroxyapatite (HAp) nanopowder was developed. The process was conducted in a microwave radiation field having a high energy density of 5 W/mL and over a time less than 2 minutes. The sample measurements included: powder X-ray diffraction, density, specific surface area, and chemical composition. The morphology and structure were investigated by scanning electron microscopy as well as transmission electron microscopy (TEM). The thermal behavior analysis was conducted using a simultaneous thermal analysis technique coupled with quadruple mass spectrometry. Additionally, Fourier transform infrared spectroscopy tests of heated samples were performed. A degradation test and a biocompatibility study in vitro using human osteoblast cells were also conducted. The developed method enables the synthesis of pure, fully crystalline hexagonal HAp nanopowder with a specific surface area close to 240 m(2)/g and a Ca/P molar ratio equal to 1.57. TEM measurements showed that this method results in particles with an average grain size below 6 nm. A 28-day degradation test conducted according to the ISO standard indicated a 22% loss of initial weight and a calcium ion concentration at 200 μmol/dm(3) in the tris(hydroxymethyl)aminomethane hydrochloride test solution. The cytocompatibility of the obtained material was confirmed in a culture of human bone derived cells, both in an indirect test using the material extract, and in direct contact. A quantitative analysis was based on the 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide. Viability assay as well as on DNA content measurements in the PicoGreen test. Indirect observations were performed at one point in time according to the ISO standard for in vitro cytotoxicity (ie, after 24 hours of cell exposure to the extracts). The direct contact tests were completed at three time points: after 24 hours, on day 7, and on day 14 of a culture in an

  18. Highly biocompatible, nanocrystalline hydroxyapatite synthesized in a solvothermal process driven by high energy density microwave radiation

    PubMed Central

    Smolen, Dariusz; Chudoba, Tadeusz; Malka, Iwona; Kedzierska, Aleksandra; Lojkowski, Witold; Swieszkowski, Wojciech; Kurzydlowski, Krzysztof Jan; Kolodziejczyk-Mierzynska, Małgorzata; Lewandowska-Szumiel, Małgorzata

    2013-01-01

    A microwave, solvothermal synthesis of highly biocompatible hydroxyapatite (HAp) nanopowder was developed. The process was conducted in a microwave radiation field having a high energy density of 5 W/mL and over a time less than 2 minutes. The sample measurements included: powder X-ray diffraction, density, specific surface area, and chemical composition. The morphology and structure were investigated by scanning electron microscopy as well as transmission electron microscopy (TEM). The thermal behavior analysis was conducted using a simultaneous thermal analysis technique coupled with quadruple mass spectrometry. Additionally, Fourier transform infrared spectroscopy tests of heated samples were performed. A degradation test and a biocompatibility study in vitro using human osteoblast cells were also conducted. The developed method enables the synthesis of pure, fully crystalline hexagonal HAp nanopowder with a specific surface area close to 240 m2/g and a Ca/P molar ratio equal to 1.57. TEM measurements showed that this method results in particles with an average grain size below 6 nm. A 28-day degradation test conducted according to the ISO standard indicated a 22% loss of initial weight and a calcium ion concentration at 200 μmol/dm3 in the tris(hydroxymethyl)aminomethane hydrochloride test solution. The cytocompatibility of the obtained material was confirmed in a culture of human bone derived cells, both in an indirect test using the material extract, and in direct contact. A quantitative analysis was based on the 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide. Viability assay as well as on DNA content measurements in the PicoGreen test. Indirect observations were performed at one point in time according to the ISO standard for in vitro cytotoxicity (ie, after 24 hours of cell exposure to the extracts). The direct contact tests were completed at three time points: after 24 hours, on day 7, and on day 14 of a culture in an osteogenic

  19. Improving radiative transfer processes in snow-covered areas prone to dust loading using a regional climate model

    NASA Astrophysics Data System (ADS)

    Oaida, C. M.; Xue, Y.; Painter, T. H.; Flanner, M. G.; De Sales, F.

    2011-12-01

    Radiative processes play an important role on both global and regional scales. This study focuses on their effects over snow-covered surfaces, both clean and dust loaded. It is well understood that dust in snow enhances solar radiation absorption, leading to a decrease in snow albedo. However, the quantitative assessment of dust's influence on radiative forcing and runoff timing in mountain snow packs has only been recently investigated. Painter et al. (2007) have shown that snow cover was shortened by 18 to 35 days due to dust radiative forcing in snow in the San Juan Mountains, Colorado, USA. This dust largely originates from the Colorado Plateau with increases of 5-7 fold in the last century and a half due to grazing and agricultural practices. For this study, we employ NCAR's WRF ARW v3.3+ model, which is coupled with a land surface model, Simplified Simple Biosphere version 3 (SSiB3). We first investigate the impact of different atmospheric radiative transfer schemes in WRF3.3+-SSiB3 on the regional climate downscaling. After conducting simulations over North America for the period March through June, we found substantial differences in the downscaling skills with different atmospheric radiative schemes. These differences indicate the uncertainty due to the atmospheric radiative transfer parameterizations. To develop a regional climate model that is capable of realistically simulating radiative forcing on snow covered areas with aerosol loading, we coupled WRF3.3+-SSiB3 with a snow-radiative transfer model, Snow, Ice, and Aerosol Radiative (SNICAR) model. SNICAR considers the effects of snow grain size and aerosol on snow albedo evolution. Snow grain size and growth is important in snow albedo feedbacks, especially when aerosols in snow are considered, because larger snow grains decrease snow albedo, and in the presence of dust, grain growth rates increase, decreasing snow reflectance even further than if the snow was pure. Our previous version of WRF3.3+-SSi

  20. Effects of aqueous effluents from in situ fossil fuel processing technologies on aquatic systems. Annual progress report, January 1-December 31, 1979

    SciTech Connect

    Bergman, H.L.

    1980-01-04

    This is the third annual progress report for a continuing EPA-DOE jointly funded project to evaluate the effects of aqueous effluents from in situ fossil-fuel processing technologies on aquatic biota. The project is organized into four project tasks: (1) literature review; (2) process water screening; (3) methods development; and (4) recommendations. Our Bibliography of aquatic ecosystem effects, analytical methods and treatment technologies for organic compounds in advanced fossil-fuel processing effluents was submitted to the EPA for publication. The bibliography contains 1314 citations indexed by chemicals, keywords, taxa and authors. We estimate that the second bibliography volume will contain approximately 1500 citations and be completed in February. We compiled results from several laboratories of inorganic characterizations of 19 process waters: 55 simulated in situ oil-shale retort waters; and Hanna-3, Hanna-4B 01W and Lawrence Livermore Hoe Creek underground coal gasification condenser waters. These process waters were then compared to a published summary of the analyses from 18 simulated in situ oil-shale retort waters. We completed this year 96-h flow-through toxicity bioassays with fathead minnows and rainbow trout and 48-h flow-through bioassays with Daphnia pulicaria exposed to 5 oil-shale process waters, 1 tar-sand process water, 2 underground coal gasification condenser waters, 1 post-gasification backflood condenser water, as well as 2 bioassays with fossil-fuel process water constituents. The LC/sub 50/ toxicity values for these respective species when exposed to these waters are given in detail. (LTN)