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


1

ARM - Measurement - Shortwave broadband diffuse downwelling irradiance  

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

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2

ARM - Measurement - Shortwave spectral diffuse downwelling irradiance  

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

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3

Use of OCA and APOLLO in Heliosat-4 method for the assessment of surface downwelling solar irradiance  

E-Print Network [OSTI]

the German Aerospace Center (DLR), for the assessment of surface downwelling solar irradiance (SSI). Each-based assessments of surface downwelling solar irradiance (SSI) are more and more used in the domain of solar energy, diffuse and direct surface irradiance for use in various domains: solar energy, biomass, agriculture

Paris-Sud XI, Université de

4

ARM: SIRS: derived, correction of downwelling shortwave diffuse hemispheric measurements using Dutton and full algorithm  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

SIRS: derived, correction of downwelling shortwave diffuse hemispheric measurements using Dutton and full algorithm

Stoffel, Tom; Kay, Bev; Habte, Aron; Anderberg, Mary; Kutchenreiter, Mark

5

ARM - Measurement - Shortwave narrowband direct downwelling irradiance  

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

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6

ARM - Measurement - Shortwave narrowband diffuse downwelling irradiance  

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

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7

ARM - Measurement - Longwave broadband downwelling irradiance  

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

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8

ARM - Measurement - Shortwave broadband direct downwelling irradiance  

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

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9

ARM - Measurement - Shortwave broadband total downwelling irradiance  

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

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10

ARM - Measurement - Shortwave narrowband total downwelling irradiance  

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

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11

ARM - Measurement - Shortwave spectral total downwelling irradiance  

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

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12

Diffuse Irradiance Study Planned for October  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed Newcatalyst phasesData FilesShape,Physics DiagnosticsMicrochips. |Energy3 Diffuse

13

Comparison of Diffuse Shortwave Irradiance Measurements  

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

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14

Simultaneous retrievals of column ozone and aerosol optical properties from direct and diffuse solar irradiance measurements  

E-Print Network [OSTI]

of column ozone and aerosol optical properties from direct and diffuse solar irradiance measurements, JSimultaneous retrievals of column ozone and aerosol optical properties from direct and diffuse solar irradiance measurements Christian D. Goering,1 Tristan S. L'Ecuyer,1 Graeme L. Stephens,1 James R

Stephens, Graeme L.

15

Assessment of clear and cloudy sky parameterizations for daily downwelling longwave radiation over different land surfaces in  

E-Print Network [OSTI]

meteorological data, resulting in reliable quantification of net radiation and evapotranspiration in FloridaAssessment of clear and cloudy sky parameterizations for daily downwelling longwave radiation over sky downwelling longwave radiation (Rldc) and cloudy sky downwelling longwave radiation (Rld) formulas

16

Preliminary Analysis of ARM SGP Area Sky Cover and Downwelling SW Irradiance  

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

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17

Investigation of the Downwelling LW Differences Between the Niamey AMF Main and Supplementary Sites  

SciTech Connect (OSTI)

The overall average downwelling longwave (LW) measured at the Niamey supplementary facility (S1) is 6-8 Wm-2 less than that measured by the two instruments located at the ARM Mobile Facility (AMF) main (N1) site. Examination of all other data available at both sites does not reveal any overarching differences that suggest this should be the case. However, examination of the pyrgeometer case and dome temperatures do suggest that the S1 values are also anomalously low, which in turn would explain the downwelling LW anomaly since the LW is calculated using these temperatures. Our recommendation then is to normalize the S1 data to the average N1 value by applying an adjustment factor to the S1 downwelling pyrgeometer case and dome temperatures (in Kelvin), then recalculating the downwelling LW values. The adjustment factor (0.00305) has been determined as that factor that brings the overall average S1 LWdn to agree with the overall average of the two N1 LWdn data series. We note that there is no reason to expect that the two site averages would actually be exactly equal to one another, and thus our recommendation is viewed as likely moving the S1 data in the right direction and by normalizing to the N1 average will help facilitate more meaningful temporal variability studies at least. It is also strongly recommended that for all future AMF deployments where supplementary sites will also be deployed, that the supplementary instrument systems (complete) be assembled as they will be operated in the field and run for at least a few days beside the corresponding AMF main site instruments, both at the beginning and end of the AMF field campaign. This is absolutely crucial so that all the measurements can be compared pre- and post-experiment to properly relate these measurements and systems, and to detect measurement anomalies such as those discussed in this report.

CN Long; P Gotseff; EG Dutton

2008-04-01T23:59:59.000Z

18

Estimation of the inherent optical properties of natural waters from the irradiance attenuation coefficient and  

E-Print Network [OSTI]

Estimation of the inherent optical properties of natural waters from the irradiance attenuation, and the backscattering bb coefficients in the upper ocean from irradiance reflectance just beneath the sea surface, R 0 , and the average attenuation coefficient for downwelling irradiance, Kd 1, between the surface and the first

Stramski, Dariusz

19

First Results of Scanning Thermal Diffusivity Microscope (STDM) Measurements on Irradiated Monolithic and Dispersion Fuel  

SciTech Connect (OSTI)

The thermal conductivity of the fuel material in a reactor before and during irradiation is a sensitive and fundamental parameter for thermal hydraulic calculations that are useds to correctly determine fuel heat fluxes and meat temperatures and to simulate performance of the fuel elements during operation. Several techniques have been developed to measure the thermal properties of fresh fuel to support these calculations, but it is crucial to also investigate the change of thermal properties during irradiation.

T. K. Huber; M. K. Figg; J. R. Kennedy; A. B. Robinson; D. M. Wachs

2012-07-01T23:59:59.000Z

20

Simple solar spectral model for direct and diffuse irradiance on horizontal and tilted planes at the earth's surface for cloudless atmospheres  

SciTech Connect (OSTI)

A new, simple model for calculating clear-sky direct and diffuse spectral irradiance on horizontal and tilted surfaces is presented. The model is based on previously reported simple algorithms and on comparisons with rigorous radiative transfer calculations and limited outdoor measurements. Equations for direct normal irradiance are outlined; and include: Raleigh scattering; aerosol scattering and absorption; water vapor absorption; and ozone and uniformly mixed gas absorption. Inputs to the model include solar zenith angle, collector tilt angle, atmospheric turbidity, amount of ozone and precipitable water vapor, surface pressure, and ground albedo. The model calculates terrestrial spectra from 0.3 to 4.0 ..mu..m with approximately 10 nm resolution. A major goal of this work is to provide researchers with the capability to calculate spectral irradiance for different atmospheric conditions and different collector geometries using microcomputers. A listing of the computer program is provided.

Bird, R.; Riordan, C.

1984-12-01T23:59:59.000Z

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


21

Monte Carlo radiative transfer simulation for the near-ocean-surface high-resolution downwelling irradiance statistics  

E-Print Network [OSTI]

We present a numerical study of the near-surface underwater solar light statistics using the state-of-the-art Monte Carlo radiative transfer (RT) simulations in the coupled atmosphere-ocean system. Advanced variance-reduction ...

Xu, Zao

22

Solar and Infrared Radiation Station (SIRS) Handbook  

SciTech Connect (OSTI)

The Solar Infrared Radiation Station (SIRS) provides continuous measurements of broadband shortwave (solar) and longwave (atmospheric or infrared) irradiances for downwelling and upwelling components. The following six irradiance measurements are collected from a network of stations to help determine the total radiative flux exchange within the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) Climate Research Facility: • Direct normal shortwave (solar beam) • Diffuse horizontal shortwave (sky) • Global horizontal shortwave (total hemispheric) • Upwelling shortwave (reflected) • Downwelling longwave (atmospheric infrared) • Upwelling longwave (surface infrared)

Stoffel, T

2005-07-01T23:59:59.000Z

23

ARM - Measurement - Shortwave narrowband diffuse upwelling irradiance  

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

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24

IRRADIATION EXPERIMENTS &  

E-Print Network [OSTI]

IRRADIATION EXPERIMENTS & FACILITIES AT BNL: BLIP & NSLS II Peter Wanderer Superconducting Magnet). Current user: LBNE ­ materials for Project X. · Long Baseline Neutrino Experiment ­ Abandoned gold mine

McDonald, Kirk

25

Safer Food with Irradiation  

E-Print Network [OSTI]

This publication answers questions about food irradiation and how it helps prevent foodborne illnesses. Included are explanations of how irradiation works and its benefits. Irradiation is a safe method of preserving food quality and ensuring its...

Thompson, Britta; Vestal, Andy; Van Laanen, Peggy

2003-01-21T23:59:59.000Z

26

Is Arnold diffusion relevant to global diffusion?  

E-Print Network [OSTI]

Global diffusion of Hamiltonian dynamical systems is investigated by using a coupled standard maps. Arnold web is visualized in the frequency space, using local rotation numbers, while Arnold diffusion and resonance overlaps are distinguished by the residence time distributions at resonance layers. Global diffusion in the phase space is shown to be accelerated by diffusion across overlapped resonances generated by the coupling term, rather than Arnold diffusion along the lower-order resonances. The former plays roles of hubs for transport in the phase space, and accelerate the diffusion.

Seiichiro Honjo; Kunihiko Kaneko

2003-07-27T23:59:59.000Z

27

Comparison of Deuterium Retention for Ion-irradiated and Neutron-irradiated Tungsten  

SciTech Connect (OSTI)

The behavior of D retention for Fe{sup 2+}-irradiated tungsten with a damage of 0.025-3 dpa was compared with that for neutron-irradiated tungsten with 0.025 dpa. The D{sub 2} thermal desorption spectroscopy (TDS) spectra for Fe{sup 2+}-irradiated tungsten consisted of two desorption stages at 450 and 550 K, while that for neutron-irradiated tungsten was composed of three stages and an addition desorption stage was found at 750 K. The desorption rate of the major desorption stage at 550K increased as the displacement damage increased due to Fe{sup 2+} irradiation increasing. In addition, the first desorption stage at 450K was found only for damaged samples. Therefore, the second stage would be based on intrinsic defects or vacancy produced by Fe{sup 2+} irradiation, and the first stage should be the accumulation of D in mono-vacancy and the activation energy would be relatively reduced, where the dislocation loop and vacancy is produced. The third one was found only for neutron irradiation, showing the D trapping by a void or vacancy cluster, and the diffusion effect is also contributed to by the high full-width at half-maximum of the TDS spectrum. Therefore, it can be said that the D{sub 2} TDS spectra for Fe{sup 2+}-irradiated tungsten cannot represent that for the neutron-irradiated one, indicating that the deuterium trapping and desorption mechanism for neutron-irradiated tungsten is different from that for the ion-irradiated one.

Yasuhisa Oya; Masashi Shimada; Makoto Kobayashi; Takuji Oda; Masanori Hara; Hideo Watanabe; Yuji Hatano; Pattrick Calderoni; Kenji Okuno

2011-12-01T23:59:59.000Z

28

Parallel flow diffusion battery  

DOE Patents [OSTI]

A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

Yeh, H.C.; Cheng, Y.S.

1984-01-01T23:59:59.000Z

29

Magnetic phase formation in irradiated austenitic alloys  

SciTech Connect (OSTI)

Austenitic alloys are often observed to develop magnetic properties during irradiation, possibly associated with radiation-induced acceleration of the ferrite phase. Some of the parametric sensitivities of this phenomenon have been addressed using a series of alloys irradiated in the BOR-60 reactor at 593K. The rate of development of magnetic phase appears to be sensitive to alloy composition. To the first order, the largest sensitivities to accelerate ferrite formation, as explored in this experiment, are associated with silicon, carbon and manganese and chromium. Si, C, and Mn are thought to influence diffusion rates of point defects while Cr plays a prominent role in defining the chromium equivalent and therefore the amount of ferrite at equilibrium. Pre-irradiation cold working was found to accelerate ferrite formation, but it can play many roles including an effect on diffusion, but on the basis of these results the dominant role or roles of cold-work cannot be identified. Based on the data available, ferrite formation is most probably associated with diffusion.

Gussev, Maxim N [ORNL] [ORNL; Busby, Jeremy T [ORNL] [ORNL; Tan, Lizhen [ORNL] [ORNL; Garner, Francis A. [Radiation Effects Consulting, Richland, WA] [Radiation Effects Consulting, Richland, WA

2014-01-01T23:59:59.000Z

30

Analysis of tritium transport in irradiated beryllium  

SciTech Connect (OSTI)

Analysis of the beryllium tritium release results with simple analytical models indicated that tritium behavior in Be is not dominated by one simple mechanism, but by a combination of several mechanisms including surface processes and helium bubbles. A model was developed and the initial version of the model included tritium diffusion in the beryllium and the beryllium oxide, second order desorption at the solid/gas interface and diffusion through interconnected porosity. Fundamental data, tritium diffusion and desorption coefficients for Be and BeO, were derived from experimental data using the model. Beryllium is a metal to which one can generally apply the concepts of diffusion, solubility, surface processes and traps. Tritium transport in the irradiated beryllium is affected by processes occurring in the bulk, He bubbles, the bulk/surface and surface/gas interfaces. There are two types of solid/gas surfaces in the irradiated Be. One is the surface at the pure Be/He bubble interface where no oxide layer exists and the other is the surface at the BeO layer/purge gas interface. Although the material characteristics of the Be and BeO layer are different and have different activation barriers, the surface processes can be applied to both interfaces.

Cho, S.; Abdou, M.A. [Univ. of California, Los Angeles, CA (United States)

1994-12-31T23:59:59.000Z

31

Response of nanostructured ferritic alloys to high-dose heavy ion irradiation  

SciTech Connect (OSTI)

A latest-generation aberration-corrected scanning/transmission electron microscope (STEM) is used to study heavy-ion-irradiated nanostructured ferritic alloys (NFAs). Results are presented for STEM X-ray mapping of NFA 14YWT irradiated with 10 MeV Pt to 16 or 160 dpa at -100°C and 750°C, as well as pre-irradiation reference material. Irradiation at -100°C results in ballistic destruction of the beneficial microstructural features present in the pre-irradiated reference material, such as Ti-Y-O nanoclusters (NCs) and grain boundary (GB) segregation. Irradiation at 750°C retains these beneficial features, but indicates some coarsening of the NCs, diffusion of Al to the NCs, and a reduction of the Cr-W GB segregation (or solute excess) content. Ion irradiation combined with the latest-generation STEM hardware allows for rapid screening of fusion candidate materials and improved understanding of irradiation-induced microstructural changes in NFAs.

Parish, Chad M.; White, Ryan M.; LeBeau, James M.; Miller, Michael K.

2014-02-01T23:59:59.000Z

32

Microfabricated diffusion source  

DOE Patents [OSTI]

A microfabricated diffusion source to provide for a controlled diffusion rate of a vapor comprises a porous reservoir formed in a substrate that can be filled with a liquid, a headspace cavity for evaporation of the vapor therein, a diffusion channel to provide a controlled diffusion of the vapor, and an outlet to release the vapor into a gas stream. The microfabricated diffusion source can provide a calibration standard for a microanalytical system. The microanalytical system with an integral diffusion source can be fabricated with microelectromechanical systems technologies.

Oborny, Michael C. (Albuquerque, NM); Frye-Mason, Gregory C. (Cedar Crest, NM); Manginell, Ronald P. (Albuquerque, NM)

2008-07-15T23:59:59.000Z

33

Formation of long-range ordered quantum dots arrays in amorphous matrix by ion beam irradiation  

SciTech Connect (OSTI)

We demonstrate the production of a well ordered three-dimensional array of Ge quantum dots in amorphous silica matrix. The ordering is achieved by ion beam irradiation and annealing of a multilayer film. Structural analysis shows that quantum dots nucleate along the direction of the ion beam used for irradiation, while the mutual distance of the quantum dots is determined by the diffusion properties of the multilayer material rather than the distances between traces of ions that are used for irradiation.

Buljan, M. [Charles University in Prague, Prague 12116 (Czech Republic); Ruder Boskovic Institute, Zagreb 10000 (Croatia); Bogdanovic-Radovic, I.; Karlusic, M.; Desnica, U. V.; Radic, N.; Dubcek, P. [Ruder Boskovic Institute, Zagreb 10000 (Croatia); Drazic, G. [Jozef Stefan Institute, Ljubljana 1000 (Slovenia); Salamon, K. [Institute of Physics, Zagreb 10000 (Croatia); Bernstorff, S. [Sincrotrone Trieste, Basovizza 34012 (Italy); Holy, V. [Charles University in Prague, Prague 12116 (Czech Republic)

2009-08-10T23:59:59.000Z

34

Irradiation response and stability of nanoporous materials  

SciTech Connect (OSTI)

Nanoporous materials consist of a regular organic or inorganic framework supporting a regular, porous structure. Pores are by definition roughly in the nanometre range, that is between 0.2 nm and 100 nm. Nanoporous materials can be subdivided into 3 categories (IUPAC): (1) Microporous materials - 0.2-2 nm; (2) Mesoporous materials - 2-50 nm; and (3) Macroporous materials - 50-1000 nm. np-Au foams were successfully synthesized by de-alloying process. np-Au foams remain porous structure after Ne ion irradiation to 1 dpa. Stacking Fault Tetrahedra (SFTs) were observed in RT irradiated np-Au foams under the highest and intermediate fluxes, but not under the lowest flux. SFTs were not observed in LNT irradiated np-Au foams under all fluxes. The vacancy diffusivity in Au at RT is high enough so that the vacancies have enough time to agglomerate and then collapse to form SFTs. The high ion flux creates more damage per unit time; vacancies don't have enough time to diffuse or recombine. As a result, SFTs were formed at high ion fluxes.

Fu, Engang [Los Alamos National Laboratory; Wang, Yongqiang [Los Alamos National Laboratory; Serrano De Caro, Magdalena [Los Alamos National Laboratory; Caro, Jose A. [Los Alamos National Laboratory; Zepeda-Ruiz, L [Lawrence Livermore national Laboratory; Bringa, E. [CONICET, Universidad de Cuyo, Argentina; Nastasi, Mike [University of Nebraska, Lincoln, NE; Baldwin, Jon K. [Los Alamos National Laboratory

2012-08-28T23:59:59.000Z

35

Discrepancies in Shortwave Diffuse Measured and Modeled Irradiances in Antarctica  

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

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36

Results of the Second Diffuse Horizontal Irradiance IOP  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared0 Resource Program September 2010 B O N N E V I L LResponseResults

37

An Instrument Design Concept for Measuring Solar Diffuse Irradiance  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmes Laboratory Site| Department ofAn Inside Look at a MOFAn

38

Comminuting irradiated ferritic steel  

DOE Patents [OSTI]

Disclosed is a method of comminuting irradiated ferritic steel by placing the steel in a solution of a compound selected from the group consisting of sulfamic acid, bisulfate, and mixtures thereof. The ferritic steel is used as cladding on nuclear fuel rods or other irradiated components.

Bauer, Roger E. (Kennewick, WA); Straalsund, Jerry L. (Kennewick, WA); Chin, Bryan A. (Auburn, AL)

1985-01-01T23:59:59.000Z

39

Irradiation Creep in Graphite  

SciTech Connect (OSTI)

An understanding of the underlying mechanisms of irradiation creep in graphite material is required to correctly interpret experimental data, explain micromechanical modeling results, and predict whole-core behavior. This project will focus on experimental microscopic data to demonstrate the mechanism of irradiation creep. High-resolution transmission electron microscopy should be able to image both the dislocations in graphite and the irradiation-induced interstitial clusters that pin those dislocations. The team will first prepare and characterize nanoscale samples of virgin nuclear graphite in a transmission electron microscope. Additional samples will be irradiated to varying degrees at the Advanced Test Reactor (ATR) facility and similarly characterized. Researchers will record microstructures and crystal defects and suggest a mechanism for irradiation creep based on the results. In addition, the purchase of a tensile holder for a transmission electron microscope will allow, for the first time, in situ observation of creep behavior on the microstructure and crystallographic defects.

Ubic, Rick; Butt, Darryl; Windes, William

2014-03-13T23:59:59.000Z

40

Enhanced electrochemical etching of ion irradiated silicon by localized amorphization  

SciTech Connect (OSTI)

A tailored distribution of ion induced defects in p-type silicon allows subsequent electrochemical anodization to be modified in various ways. Here we describe how a low level of lattice amorphization induced by ion irradiation influences anodization. First, it superposes a chemical etching effect, which is observable at high fluences as a reduced height of a micromachined component. Second, at lower fluences, it greatly enhances electrochemical anodization by allowing a hole diffusion current to flow to the exposed surface. We present an anodization model, which explains all observed effects produced by light ions such as helium and heavy ions such as cesium over a wide range of fluences and irradiation geometries.

Dang, Z. Y.; Breese, M. B. H. [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore Singapore 117542 (Singapore); Lin, Y.; Tok, E. S. [Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore); Vittone, E. [Physics Department, NIS Excellence Centre and CNISM, University of Torino, via Pietro Giuria 1, 10125 Torino (Italy)

2014-05-12T23:59:59.000Z

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


41

Tungsten diffusion in silicon  

SciTech Connect (OSTI)

Two doses (10{sup 13} and 10{sup 15}?cm{sup ?2}) of tungsten (W) atoms were implanted in different Si(001) wafers in order to study W diffusion in Si. The samples were annealed or oxidized at temperatures between 776 and 960?°C. The diffusion profiles were measured by secondary ion mass spectrometry, and defect formation was studied by transmission electron microscopy and atom probe tomography. W is shown to reduce Si recrystallization after implantation and to exhibit, in the temperature range investigated, a solubility limit close to 0.15%–0.2%, which is higher than the solubility limit of usual metallic impurities in Si. W diffusion exhibits unusual linear diffusion profiles with a maximum concentration always located at the Si surface, slower kinetics than other metals in Si, and promotes vacancy accumulation close to the Si surface, with the formation of hollow cavities in the case of the higher W dose. In addition, Si self-interstitial injection during oxidation is shown to promote W-Si clustering. Taking into account these observations, a diffusion model based on the simultaneous diffusion of interstitial W atoms and W-Si atomic pairs is proposed since usual models used to model diffusion of metallic impurities and dopants in Si cannot reproduce experimental observations.

De Luca, A.; Texier, M.; Burle, N.; Oison, V.; Pichaud, B. [Aix-Marseille Université, IM2NP UMR 7334, Faculté des Sciences et Techniques, Campus de Saint-Jérôme, Avenue Escadrille Normandie Niemen - Case 142, F-13397 Marseille Cedex (France); Portavoce, A., E-mail: alain.portavoce@im2np.fr [CNRS, IM2NP UMR 7334, Faculté des Sciences et Techniques, Campus de Saint-Jérôme, Avenue Escadrille Normandie Niemen - Case 142, F-13397 Marseille Cedex (France); Grosjean, C. [STMicroelectronics, Rousset (France)

2014-01-07T23:59:59.000Z

42

Adaptive multigroup radiation diffusion  

E-Print Network [OSTI]

This thesis describes the development and implementation of an algorithm for dramatically increasing the accuracy and reliability of multigroup radiation diffusion simulations at low group counts. This is achieved by ...

Williams, Richard B., Sc. D. Massachusetts Institute of Technology

2005-01-01T23:59:59.000Z

43

Diffusion Maps for Changing Data Diffusion Maps for Changing Data  

E-Print Network [OSTI]

Diffusion Maps for Changing Data Diffusion Maps for Changing Data Matthew J. Hirn Department;Diffusion Maps for Changing Data Collaborators Ronald Coifman (Yale University) Roy Lederman (Yale University) #12;Diffusion Maps for Changing Data How to compare images across sensors? Figure: Sokolov Mine

Hirn, Matthew

44

Diffusion Maps for Changing Data Diffusion Maps for Changing Data  

E-Print Network [OSTI]

Diffusion Maps for Changing Data Diffusion Maps for Changing Data Matthew J. Hirn Department of Mathematics Yale University July 26, 2012 Bell Labs #12;Diffusion Maps for Changing Data Collaborators Joint work with Ronald Coifman and Roy Lederman. #12;Diffusion Maps for Changing Data Overview 1 High

Hirn, Matthew

45

Diffusion Maps for Changing Data Diffusion Maps for Changing Data  

E-Print Network [OSTI]

Diffusion Maps for Changing Data Diffusion Maps for Changing Data Matthew J. Hirn Department of Mathematics Yale University November 29, 2012 Kansas State University Colloquium #12;Diffusion Maps;Diffusion Maps for Changing Data How to compare images across sensors? Figure: Sokolov Mine in 2009 and 2010

Hirn, Matthew

46

Diffusion Maps for Changing Data Diffusion Maps for Changing Data  

E-Print Network [OSTI]

Diffusion Maps for Changing Data Diffusion Maps for Changing Data Matthew J. Hirn Department in Honor of the 70th Birthday of David R. Larson #12;Diffusion Maps for Changing Data Collaborators Joint work with Ronald Coifman and Roy Lederman. #12;Diffusion Maps for Changing Data High Dimensional Data

Hirn, Matthew

47

Diffusion Maps for Changing Data Diffusion Maps for Changing Data  

E-Print Network [OSTI]

Diffusion Maps for Changing Data Diffusion Maps for Changing Data Matthew J. Hirn September 3, 2013 #12;Diffusion Maps for Changing Data Collaborators Simon Adar, Tel Aviv University Eyal Ben Dor, Tel, Clarkson University Yoel Shkolnisky, Tel Aviv University #12;Diffusion Maps for Changing Data Heat equation

Hirn, Matthew

48

Comparison of /sup 32/P therapy and sequential hemibody irradiation (HBI) for bony metastases as methods of whole body irradiation  

SciTech Connect (OSTI)

We report a retrospective study of 15 patients with prostate carcinoma and diffuse bone metastases treated with sodium /sup 32/P for palliation of pain at Downstate Medical Center and Kings County Hospital from 1973 to 1978. The response rates, duration of response, and toxicities are compared with those of other series of patients treated with /sup 32/P and with sequential hemibody irradiation. The response rates and duration of response are similar with both modalities ranging from 58 to 95% with a duration of 3.3 to 6 months with /sup 32/P and from 75 to 86% with a median duration of 5.5 months with hemibody irradiation. There are significant differences in the patterns of response and in the toxicities of the two treatment methods. Both methods cause significant bone marrow depression. Acute radiation syndrome, radiation pneumonitis, and alopecia are seen with sequential hemibody irradiation and not with /sup 32/P, but their incidence can be reduced by careful treatment planning. Hemibody irradiation can provide pain relief within 24 to 48 h, while /sup 32/P may produce an initial exacerbation of pain. Lower hemibody irradiation alone is less toxic than either upper hemibody irradiation or /sup 32/P treatment.

Aziz, H.; Choi, K.; Sohn, C.; Yaes, R.; Rotman, M.

1986-06-01T23:59:59.000Z

49

Effects of neutron irradiation on thermal conductivity of SiC-based composites and monolithic ceramics  

SciTech Connect (OSTI)

A variety of SiC-based composites and monolithic ceramics were characterized by measuring their thermal diffusivity in the unirradiated, thermal annealed, and irradiated conditions over the temperature range 400 to 1,000 C. The irradiation was conducted in the EBR-II to doses of 33 and 43 dpa-SiC (185 EFPD) at a nominal temperature of 1,000 C. The annealed specimens were held at 1,010 C for 165 days to approximately duplicate the thermal exposure of the irradiated specimens. Thermal diffusivity was measured using the laser flash method, and was converted to thermal conductivity using density data and calculated specific heat values. Exposure to the 165 day anneal did not appreciably degrade the conductivity of the monolithic or particulate-reinforced composites, but the conductivity of the fiber-reinforced composites was slightly degraded. The crystalline SiC-based materials tested in this study exhibited thermal conductivity degradation of irradiation, presumably caused by the presence of irradiation-induced defects. Irradiation-induced conductivity degradation was greater at lower temperatures, and was typically more pronounced for materials with higher unirradiated conductivity. Annealing the irradiated specimens for one hour at 150 C above the irradiation temperature produced an increase in thermal conductivity, which is likely the result of interstitial-vacancy pair recombination. Multiple post-irradiation anneals on CVD {beta}-SiC indicated that a portion of the irradiation-induced damage was permanent. A possible explanation for this phenomenon was the formation of stable dislocation loops at the high irradiation temperature and/or high dose that prevented subsequent interstitial/vacancy recombination.

Senor, D.J.; Youngblood, G.E. [Pacific Northwest National Lab., Richland, WA (United States); Moore, C.E. [Auburn Univ., AL (United States); Trimble, D.J. [Westinghouse Hanford Co., Richland, WA (United States); Woods, J.J. [Lockheed Martin, Schenectady, NY (United States)

1996-06-01T23:59:59.000Z

50

Effects of neutron irradiation on thermal conductivity of SiC-based composites and monolithic ceramics  

SciTech Connect (OSTI)

A variety of SiC-based composites and monolithic ceramics were characterized by measuring their thermal diffusivity in the unirradiated, thermal annealed, and irradiated conditions over the temperature range 400 to 1,000 C. The irradiation was conducted in the EBR-II to doses of 33 and 43 dpa-SiC (185 EFPD) at a nominal temperature of 1,000 C. The annealed specimens were held at 1,010 C for 165 days to approximately duplicate the thermal exposure of the irradiated specimens. Thermal diffusivity was measured using the laser flash method, and was converted to thermal conductivity using density data and calculated specific heat values. Exposure to the 165 day anneal did not appreciably degrade the conductivity of the monolithic or particulate-reinforced composites, but the conductivity of the fiber-reinforced composites was slightly degraded. The crystalline SiC-based materials tested in this study exhibited thermal conductivity degradation after irradiation, presumably caused by the presence of irradiation-induced defects. Irradiation-induced conductivity degradation was greater at lower temperatures, and was typically more pronounced for materials with higher unirradiated conductivity. Annealing the irradiated specimens for one hour at 150 C above the irradiation temperature produced an increase in thermal conductivity, which is likely the result of interstitial-vacancy pair recombination. Multiple post-irradiation anneals on CVD {beta}-SiC indicated that a portion of the irradiation-induced damage was permanent. A possible explanation for this phenomenon was the formation of stable dislocation loops at the high irradiation temperature and/or high dose that prevented subsequent interstitial/vacancy recombination.

Senor, D.J.; Youngblood, G.E. [Pacific Northwest National Lab., Richland, WA (United States); Moore, C.E. [Auburn Univ., AL (United States); Trimble, D.J. [Westinghouse Hanford Co., Richland, WA (United States); Woods, J.J. [Lockheed Martin, Schenectady, NY (United States)

1997-05-01T23:59:59.000Z

51

Irradiation response in weldment and HIP joint of reduced activation ferritic/martensitic steel, F82H  

SciTech Connect (OSTI)

This work investigates irradiation response in the joints of F82H employed for a fusion breeding blanket. The joints, which were prepared using welding and diffusion welding, were irradiated up to 6 dpa in the High Flux Isotope Reactor at the Oak Ridge National Laboratory. Post-irradiation tests revealed hardening in weldment (WM) and base metal (BM) greater than 300 MPa. However, the heat affected zones (HAZ) exhibit about half that of WM and BM. Therefore, neutron irradiation decreased the strength of the HAZ, leaving it in danger of local deformation in this region. Further the hardening in WM made with an electron beam was larger than that in WM made with tungsten inert gas welding. However the mechanical properties of the diffusion-welded joint were very similar to those of BM even after the irradiation.

Hirose, Takanori [Japan Atomic Energy Agency (JAEA)] [Japan Atomic Energy Agency (JAEA); Sokolov, Mikhail A [ORNL] [ORNL; Ando, M. [Japan Atomic Energy Agency (JAEA)] [Japan Atomic Energy Agency (JAEA); Tanigawa, H. [Japan Atomic Energy Agency (JAEA)] [Japan Atomic Energy Agency (JAEA); Shiba, K. [Japan Atomic Energy Agency (JAEA)] [Japan Atomic Energy Agency (JAEA); Stoller, Roger E [ORNL] [ORNL; Odette, G.R. [University of California, Santa Barbara] [University of California, Santa Barbara

2013-01-01T23:59:59.000Z

52

Irradiation Stability of Carbon Nanotubes  

E-Print Network [OSTI]

Ion irradiation of carbon nanotubes is a tool that can be used to achieve modification of the structure. Irradiation stability of carbon nanotubes was studied by ion and electron bombardment of the samples. Different ion species at various energies...

Aitkaliyeva, Assel

2010-01-14T23:59:59.000Z

53

Oxygen diffusion in titanite: Lattice diffusion and fast-path diffusion in single crystals  

E-Print Network [OSTI]

Oxygen diffusion in titanite: Lattice diffusion and fast-path diffusion in single crystals X June 2006 Editor: P. Deines Abstract Oxygen diffusion in natural and synthetic single-crystal titanite was characterized under both dry and water-present conditions. For the dry experiments, pre-polished titanite

Watson, E. Bruce

54

Modeling the effect of irradiation and post-irradiation annealing on grain boundary composition in austenitic Fe-Cr-Ni alloys.  

SciTech Connect (OSTI)

Many irradiation effects in Fe-Cr-Ni alloys such as radiation-induced segregation, radiation-enhanced diffusion, and void swelling are known to vary with bulk alloy composition. The development of microstructural and microchemical changes during irradiation and during post-irradiation annealing is determined by the rate of diffusion of point defects and alloying elements. To accurately predict the changes in grain boundary chemistry due to radiation-induced segregation and post-irradiation annealing, the composition dependence of diffusion parameters, such as the migration energy, must be known. A model has been developed which calculates migration diffusivity. The advantages of this calculational method are that a single set of input parameters can be used for a wide range of bulk alloy compositions, and the effects of local order can easily be incorporated into the calculations. A description of the model is presented, and model calculations are compared to segregation measurements from seven different iron-chromium-nickel alloys, irradiated with protons to doses from 0.1 to 3.0 dpa at temperatures between 200 C and 600 C. Results show that segregation trends can be modeled using a single set of input parameters with the difference between model calculation and measurement being less than 5 at%, but usually less than 2 at%. Additionally, model predictions are compared to grain boundary composition measurements of neutron irradiated 304 stainless steel following annealing. For the limited annealing data available, model calculations correctly predict the magnitude and time scale for recovery of the grain boundary composition.

Allen, T.; Busby, J. T.; Kenik, E. A.; Was, G. S.

1998-03-05T23:59:59.000Z

55

OXYGEN DIFFUSION IN HYPOSTOICHIOMETRIC URANIUM DIOXIDE  

E-Print Network [OSTI]

Research Division OXYGEN DIFFUSION IN HYPOSTOICHIOMETRIC11905 -DISCLAIMER - OXYGEN DIFFUSION IN HYPOSTOICHIOMETRICc o n e e n i g woroxygen self-diffusion coefficient

Kim, Kee Chul

2010-01-01T23:59:59.000Z

56

Dissolution of ordered precipitates under ion irradiation  

SciTech Connect (OSTI)

The stability of the ordered {gamma}{prime} precipitates under 300-keV Ni{sup +} irradiation was investigated between room temperature and 623 K. The two competing mechanisms of destabilization by cascade producing irradiation, i.e. disordering and dissolution of the {gamma}{prime} precipitates in Nimonic PE16 alloy, has been studied separately by electron microscopy and field-ion microscopy with atom probe. At high temperatures, the precipitates are stable. At intermediate temperatures, the precipitates dissolve by ballistic mixing into the matrix, but the interface is restored by the radiation-enhanced atomic jumps. The order in the precipitates remains stable. At low temperatures, the precipitates are dissolved by atomic mixing. The dissolution proceeds in a diffusional manner with a diffusion coefficient normalized by the displacement rate D/K = 0.75 nm{sup 2}dpa{sup {minus}1}. The precipitates become disordered by a fluence of 0.1 dpa, whereas precipitate dissolution needs much higher fluences.

Camus, E.; Bourdeau, F.; Abromeit, C.; Wanderka, N.; Wollenberger, H. [Hahn-Meitner-Institut Berlin GmbH (Germany)

1995-09-01T23:59:59.000Z

57

24-hours ahead global irradiation forecasting using Multi-Layer Cyril Voyant1*  

E-Print Network [OSTI]

; it is shown that the most relevant is based on a multi- output MLP using endogenous and exogenous input data ahead. In the case of solar plants, the driving factor is the global solar irradiation (sum of direct and diffuse solar radiation projected on a plane (Wh/m˛)). This paper focuses on the 24-hours ahead forecast

Paris-Sud XI, Université de

58

Peridynamic thermal diffusion  

SciTech Connect (OSTI)

This study presents the derivation of ordinary state-based peridynamic heat conduction equation based on the Lagrangian formalism. The peridynamic heat conduction parameters are related to those of the classical theory. An explicit time stepping scheme is adopted for numerical solution of various benchmark problems with known solutions. It paves the way for applying the peridynamic theory to other physical fields such as neutronic diffusion and electrical potential distribution.

Oterkus, Selda [Department of Aerospace and Mechanical Engineering, The University of Arizona, Tucson, AZ 85721 (United States); Madenci, Erdogan, E-mail: madenci@email.arizona.edu [Department of Aerospace and Mechanical Engineering, The University of Arizona, Tucson, AZ 85721 (United States); Agwai, Abigail [Intel Corporation, Chandler, AZ 85226 (United States)

2014-05-15T23:59:59.000Z

59

Light diffusing fiber optic chamber  

DOE Patents [OSTI]

A light diffusion system for transmitting light to a target area. The light is transmitted in a direction from a proximal end to a distal end by an optical fiber. A diffusing chamber is operatively connected to the optical fiber for transmitting the light from the proximal end to the distal end and transmitting said light to said target area. A plug is operatively connected to the diffusing chamber for increasing the light that is transmitted to the target area.

Maitland, Duncan J. (Lafayette, CA)

2002-01-01T23:59:59.000Z

60

Microviscometric studies on thermal diffusion  

E-Print Network [OSTI]

HICROVISCKStTRIC STUDIES THERMAL DIFFUSION A Thesis Eddie Reyfls Submitted to the Grsducte School of the Agricultursl sfld Mechanical College of Texas in partisl fulfillment of the requireeeflts far the degree of MASTER OF SCIENCE August... microliter samples to 1'/ reproduceability, This equipment is used to observe the thermal diffusion effects of polystyrene in toluene solutions in c 01uslus-Dickel thermal diffusion column. An inversion in the values of concentration and molecular veight...

Reyna, Eddie

2012-06-07T23:59:59.000Z

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


61

NANOSTRUCTURE PATTERNING UNDER ENERGETIC PARTICLE BEAM IRRADIATION  

SciTech Connect (OSTI)

Energetic ion bombardment can lead to the development of complex and diverse nanostructures on or beneath the material surface through induced self-organization processes. These self-organized structures have received particular interest recently as promising candidates as simple, inexpensive, and large area patterns, whose optical, electronic and magnetic properties are different from those in the bulk materials [1-5]. Compared to the low mass efficiency production rate of lithographic methods, these self-organized approaches display new routes for the fabrication of nanostructures over large areas in a short processing time at the nanoscale, beyond the limits of lithography [1,4]. Although it is believed that surface nanostructure formation is based on the morphological instability of the sputtered surface, driven by a kinetic balance between roughening and smoothing actions [6,7], the fundamental mechanisms and experimental conditions for the formation of these nanostructures has still not been well established, the formation of the 3-D naopatterns beneath the irradiated surface especially needs more exploration. During the last funding period, we have focused our efforts on irradiation-induced nanostructures in a broad range of materials. These structures have been studied primarily through in situ electron microscopy during electron or ion irradiation. In particular, we have performed studies on 3-D void/bubble lattices (in metals and CaF2), embedded sponge-like porous structure with uniform nanofibers in irradiated semiconductors (Ge, GaSb, and InSb), 2-D highly ordered pattern of nanodroplets (on the surface of GaAs), hexagonally ordered nanoholes (on the surface of Ge), and 1-D highly ordered ripple and periodic arrays (of Cu nanoparticles) [3,8-11]. The amazing common feature in those nanopatterns is the uniformity of the size of nanoelements (nanoripples, nanodots, nanovoids or nanofibers) and the distance separating them. Our research focuses on the understanding of fundamental scientific basis for the irradiation-induced self-organization processes. The fundamental physical mechanisms underlying ordered pattern formation, which include defect production and migration, ion sputtering, redeposition, viscous flow and diffusion, are investigated through a combination of modeling and in situ and ex-situ observations [3,9,11]. In addition, these nanostructured materials exhibit considerable improvement of optical properties [9,12,13]. For example, patterned Ge with a hexagonally ordered, honeycomb-like structure of nanoscale holes possesses a high surface area and a considerably blue-shifted energy gap [9], and oxidation of ordered Ga droplets shows noticeable enhancement of optical transmission [12]. This research has addressed nanopattern formation in a variety of materials under ion bombardment and provided a fundamental understanding of the dynamic mechanisms involved. In addition, have also stared to systematically investigate pattern formation under ion irradiation for more systems with varied experimental conditions and computation, including the collaboration with Dr. Veena Tikare of Sandia National Laboratory with a hybrid computation method at the ending this grant. A more detailed relationship between nanostructure formation and experimental conditions will be revealed with our continued efforts.

Wang, Lumin [Regents of the University of Michigan; Lu, Wei [Regents of the University of Michigan

2013-01-31T23:59:59.000Z

62

Turing instability in reaction-diffusion systems with nonlinear diffusion  

SciTech Connect (OSTI)

The Turing instability is studied in two-component reaction-diffusion systems with nonlinear diffusion terms, and the regions in parametric space where Turing patterns can form are determined. The boundaries between super- and subcritical bifurcations are found. Calculations are performed for one-dimensional brusselator and oregonator models.

Zemskov, E. P., E-mail: zemskov@ccas.ru [Russian Academy of Sciences, Dorodnicyn Computing Center (Russian Federation)

2013-10-15T23:59:59.000Z

63

DIFFUSION IN SOLIDSDIFFUSION IN SOLIDS FICK'S LAWS  

E-Print Network [OSTI]

Diffusion bonding To comprehend many materials related phenomenon one must understand Diffusion. The focusDIFFUSION IN SOLIDSDIFFUSION IN SOLIDS FICK'S LAWS KIRKENDALL EFFECT ATOMIC MECHANISMS Diffusion in Solids P.G. Shewmon McGraw-Hill, New York (1963) #12;Oxidation Roles of Diffusion Creep Aging

Subramaniam, Anandh

64

BDP: BrainSuite Diffusion Pipeline  

E-Print Network [OSTI]

BDP: BrainSuite Diffusion Pipeline Chitresh Bhushan #12; Quantify microstructural tissue ROI Connectivity ROI Statistics MPRAGE Diffusion #12;Diffusion Pipeline Dicom to NIfTI Co ROIs Custom ROIs #12;Diffusion Pipeline Dicom to NIfTI Co-registration Diffusion Modeling Tractography

Leahy, Richard M.

65

Portable vapor diffusion coefficient meter  

DOE Patents [OSTI]

An apparatus for measuring the effective vapor diffusion coefficient of a test vapor diffusing through a sample of porous media contained within a test chamber. A chemical sensor measures the time-varying concentration of vapor that has diffused a known distance through the porous media. A data processor contained within the apparatus compares the measured sensor data with analytical predictions of the response curve based on the transient diffusion equation using Fick's Law, iterating on the choice of an effective vapor diffusion coefficient until the difference between the predicted and measured curves is minimized. Optionally, a purge fluid can forced through the porous media, permitting the apparatus to also measure a gas-phase permeability. The apparatus can be made lightweight, self-powered, and portable for use in the field.

Ho, Clifford K. (Albuquerque, NM)

2007-06-12T23:59:59.000Z

66

Proton irradiation effect on SCDs  

E-Print Network [OSTI]

The Low Energy X-ray Telescope is a main payload on the Hard X-ray Modulation Telescope satellite. The swept charge device is selected for the Low Energy X-ray Telescope. As swept charge devices are sensitive to proton irradiation, irradiation test was carried out on the HI-13 accelerator at the China Institute of Atomic Energy. The beam energy was measured to be 10 MeV at the SCD. The proton fluence delivered to the SCD was $3\\times10^{8}\\mathrm{protons}/\\mathrm{cm}^{2}$ over two hours. It is concluded that the proton irradiation affects both the dark current and the charge transfer inefficiency of the SCD through comparing the performance both before and after the irradiation. The energy resolution of the proton-irradiated SCD is 212 eV@5.9 keV at $-60\\,^{\\circ}\\mathrm{C}$, while it before irradiated is 134 eV. Moreover, better performance can be reached by lowering the operating temperature of the SCD on orbit.

Yan-Ji Yang; Jing-Bin Lu; Yu-Sa Wang; Yong Chen; Yu-Peng Xu; Wei-Wei Cui; Wei Li; Zheng-Wei Li; Mao-Shun Li; Xiao-Yan Liu; Juan Wang; Da-Wei Han; Tian-Xiang Chen; Cheng-Kui Li; Jia Huo; Wei Hu; Yi Zhang; Bo Lu; Yue Zhu; Ke-Yan Ma; Di Wu; Yan Liu; Zi-Liang Zhang; Guo-He Yin; Yu Wang

2014-04-19T23:59:59.000Z

67

Molecular imaging of water binding state and diffusion in breast cancer using diffuse optical spectroscopy and diffusion weighted MRI  

E-Print Network [OSTI]

Molecular imaging of water binding state and diffusion inChung et al. , “In vivo water state measurements in breastby measuring tis- sue water state using diffuse optical

Chung, So Hyun; Yu, Hon; Su, Min-Ying; Cerussi, Albert E.; Tromberg, Bruce J.

2012-01-01T23:59:59.000Z

68

Diffuser for augmenting a wind turbine  

DOE Patents [OSTI]

A diffuser for augmenting a wind turbine having means for energizing the boundary layer at several locations along the diffuser walls is improved by the addition of a short collar extending radially outward from the outlet of the diffuser.

Foreman, Kenneth M. (North Bellmore, NY); Gilbert, Barry L. (Westbury, NY)

1984-01-01T23:59:59.000Z

69

Effects of turbulent diffusion on the chemistry of diffuse clouds  

E-Print Network [OSTI]

Aims. We probe the effect of turbulent diffusion on the chemistry at the interface between a cold neutral medium (CNM) cloudlet and the warm neutral medium (WNM). Methods. We perform moving grid, multifluid, 1D, hydrodynamical simulations with chemistry including thermal and chemical diffusion. The diffusion coefficients are enhanced to account for turbulent diffusion. We post-process the steady-states of our simulations with a crude model of radiative transfer to compute line profiles. Results. Turbulent diffusion spreads out the transition region between the CNM and the WNM. We find that the CNM slightly expands and heats up: its CH and H$_2$ content decreases due to the lower density. The change of physical conditions and diffusive transport increase the H$^+$ content in the CNM which results in increased OH and H$_2$O. Diffusion transports some CO out of the CNM. It also brings H$_2$ into contact with the warm gas with enhanced production of CH$^+$, H$_3^+$, OH and H$_2$O at the interface. O lines are sensitive to the spread of the thermal profile in the intermediate region between the CNM and the WNM. Enhanced molecular content at the interface of the cloud broadens the molecular line profiles and helps exciting transitions of intermediate energy. The relative molecular yield are found higher for bigger clouds. Conclusions. Turbulent diffusion can be the source of additional molecular production and should be included in chemical models of the interstellar medium (ISM). It also is a good candidate for the interpretation of observational problems such as warm H$_2$, CH$^+$ formation and presence of H$_3^+$.

P. Lesaffre; M. Gerin; P. Hennebelle

2007-04-24T23:59:59.000Z

70

Defect Structure and Evolution in Silicon Carbide Irradiated to 1 dpa-SiC at 1100 C  

SciTech Connect (OSTI)

Transmission electron microscopy (TEM), swelling measurements, isochronal annealing, and thermal diffusivity testing were used to characterize the effects of radiation damage in SiC. Together, these techniques provided a comprehensive set of tools for observing and characterizing the structure and evolution of radiation-induced defects in SiC as a function of irradiation temperature and dose. In this study, two types of dense, crystalline, monolithic SiC were subjected to irradiation doses up to 1 dpa-SiC at a temperature of 1100 C, as well as post-irradiation annealing up to 1500 C. The microscopic defect structures observed by TEM were correlated to changes in the macroscopic dimensions, thermal diffusivity and thermal conductivity. The results demonstrated the value of using ultrapure {beta}SiC as an effective reference material to characterize the nature of expected radiation damage in other, more complex, SiC-based materials such as SiC/SiC composites.

D.J. Senor; G.E. Youngblood; L.R. Greenwood; D.V. Archer; D.L. Alexander; M.C. Chen; G.A. Newsome

2002-05-13T23:59:59.000Z

71

IRRADIATION PERFORMANCE OF U-Mo MONOLITHIC FUEL  

SciTech Connect (OSTI)

High-performance research reactors require fuel that operates at high specific power to high fission density, but at relatively low temperatures. Research reactor fuels are designed for efficient heat rejection, and are composed of assemblies of thin-plates clad in aluminum alloy. The development of low-enriched fuels to replace high-enriched fuels for these reactors requires a substantially increased uranium density in the fuel to offset the decrease in enrichment. Very few fuel phases have been identified that have the required combination of very-high uranium density and stable fuel behavior at high burnup. UMo alloys represent the best known tradeoff in these properties. Testing of aluminum matrix U-Mo aluminum matrix dispersion fuel revealed a pattern of breakaway swelling behavior at intermediate burnup, related to the formation of a molybdenum stabilized high aluminum intermetallic phase that forms during irradiation. In the case of monolithic fuel, this issue was addressed by eliminating, as much as possible, the interfacial area between U-Mo and aluminum. Based on scoping irradiation test data, a fuel plate system composed of solid U-10Mo fuel meat, a zirconium diffusion barrier, and Al6061 cladding was selected for development. Developmental testing of this fuel system indicates that it meets core criteria for fuel qualification, including stable and predictable swelling behavior, mechanical integrity to high burnup, and geometric stability. In addition, the fuel exhibits robust behavior during power-cooling mismatch events under irradiation at high power.

M.K. Meyer; J. Gan; J.-F. Jue; D.D. Keiser; E. Perez; A. Robinson; D.M. Wachs; N. Woolstenhulme; G.L. Hofman; Y.-S. Kim

2014-04-01T23:59:59.000Z

72

ARM Multi-Filter Rotating Shadowband Radiometer (MFRSR): irradiances  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The multifilter rotating shadowband radiometer (MFRSR) takes spectral measurements of direct normal, diffuse horizontal and total horizontal solar irradiances. These measurements are at nominal wavelengths of 415, 500, 615, 673, 870, and 940 nm. The measurements are made at a user-specified time interval, usually about one minute or less. The sampling rate for the Atmospheric Radiation Measurement (ARM) Climate Research Facility MFRSRs is 20 seconds. From such measurements, one may infer the atmosphere's optical depth at the wavelengths mentioned above. In turn, these optical depths may be used to derive information about the column abundances of ozone and water vapor (Michalsky et al. 1995), as well as aerosol (Michalsky et al. 1994) and other atmospheric constituents. A silicon detector is also part of the MFRSR. This detector provides a measure of the broadband direct normal, diffuse horizontal and total horizontal solar irradiances. A MFRSR head that is mounted to look vertically downward can measure upwelling spectral irradiances. In the ARM system, this instrument is called a multifilter radiometer (MFR). At the Southern Great Plains (SGP) there are two MFRs; one mounted at the 10-m height and the other at 25 m. At the North Slope of Alaska (NSA) sites, the MFRs are mounted at 10 m. MFRSR heads are also used to measure normal incidence radiation by mounting on a solar tracking device. These are referred to as normal incidence multi-filter radiometers (NIMFRs) and are located at the SGP and NSA sites. Another specialized use for the MFRSR is the narrow field of view (NFOV) instrument located at SGP. The NFOV is a ground-based radiometer (MFRSR head) that looks straight up.

Hodges, Gary

73

Hot carrier diffusion in graphene  

E-Print Network [OSTI]

We report an optical study of charge transport in graphene. Diffusion of hot carriers in epitaxial graphene and reduced graphene oxide samples are studied using an ultrafast pump-probe technique with a high spatial resolution. Spatiotemporal...

Ruzicka, Brian Andrew; Wang, Shuai; Werake, Lalani Kumari; Weintrub, Ben; Loh, Kian Ping; Zhao, Hui

2010-11-01T23:59:59.000Z

74

Accelerating and Retarding Anomalous Diffusion  

E-Print Network [OSTI]

In this paper Gaussian models of retarded and accelerated anomalous diffusion are considered. Stochastic differential equations of fractional order driven by single or multiple fractional Gaussian noise terms are introduced to describe retarding and accelerating subdiffusion and superdiffusion. Short and long time asymptotic limits of the mean squared displacement of the stochastic processes associated with the solutions of these equations are studied. Specific cases of these equations are shown to provide possible descriptions of retarding or accelerating anomalous diffusion.

Chai Hok Eab; S. C. Lim

2012-01-14T23:59:59.000Z

75

Devitrite-based Optical Diffusers  

E-Print Network [OSTI]

technological use of this devitrification product in soda–lime–silica glasses, in contrast to other inorganic glasses in which controlled devitrification has given rise to the family of materials known as glass-ceramics.5 Here we present data on the inherent... , photovoltaic,9 photolithography,10 and in the health industry for producing diffused therapeutic thermal energy.11 Visual display systems also require diffusers for increasing the field of view; with the emergence of light emitting diodes (LEDs...

Butt, Haider; Knowles, Kevin M.; Montelongo, Yunuen; Amaratunga, Gehan A. J.; Wilkinson, Timothy D.

2014-02-21T23:59:59.000Z

76

Neutron irradiation of beryllium pebbles  

SciTech Connect (OSTI)

Seven subcapsules from the FFTF/MOTA 2B irradiation experiment containing 97 or 100% dense sintered beryllium cylindrical specimens in depleted lithium have been opened and the specimens retrieved for postirradiation examination. Irradiation conditions included 370 C to 1.6 {times} 10{sup 22} n/cm{sup 2}, 425 C to 4.8 {times} 10{sup 22} n/cm{sup 2}, and 550 C to 5.0 {times} 10{sup 22} n/cm{sup 2}. TEM specimens contained in these capsules were also retrieved, but many were broken. Density measurements of the cylindrical specimens showed as much as 1.59% swelling following irradiation at 500 C in 100% dense beryllium. Beryllium at 97% density generally gave slightly lower swelling values.

Gelles, D.S.; Ermi, R.M. [Pacific Northwest National Lab., Richland, WA (United States); Tsai, H. [Argonne National Lab., IL (United States)

1998-03-01T23:59:59.000Z

77

Laser irradiation of carbon nanotube films: Effects and heat dissipation probed by Raman spectroscopy  

SciTech Connect (OSTI)

We investigate the thermal properties of thin films formed by single- and multi-walled carbon nanotubes submitted to laser irradiation using Raman scattering as a probe of both the tube morphology and the local temperature. The nanotubes were submitted to heating/cooling cycles attaining high laser intensities ({approx}1.4 MW/cm{sup 2}) under vacuum and in the presence of an atmosphere, with and without oxygen. We investigate the heat diffusion of the irradiated nanotubes to their surroundings and the effect of laser annealing on their properties. The presence of oxygen during laser irradiation gives rise to an irreversible increase of the Raman efficiency of the carbon nanotubes and to a remarkable increase of the thermal conductivity of multi-walled films. The second effect can be applied to design thermal conductive channels in devices based on carbon nanotube films using laser beams.

Mialichi, J. R.; Brasil, M. J. S. P.; Iikawa, F. [Instituto de Fisica 'Gleb Wataghin,' Unicamp, Campinas, 13083-859 Sao Paulo (Brazil); Verissimo, C.; Moshkalev, S. A. [Centro de Componentes Semicondutores, Unicamp, Campinas, 13083-870 Sao Paulo (Brazil)

2013-07-14T23:59:59.000Z

78

Structure and composition of phases occurring in austenitic stainless steels in thermal and irradiation environments  

SciTech Connect (OSTI)

Transmission electron diffraction techniques coupled with quantitative x-ray energy dispersive spectroscopy have been used to characterize the phases which develop in austenitic stainless steels during exposure to thermal and to irradiation environments. In AISI 316 and Ti-modified stainless steels some thirteen phases have been identified and characterized in terms of their crystal structure and chemical composition. Irradiation does not produce any completely new phases. However, as a result of radiation-induced segregation principally of Ni and Si, and of enhanced diffusion rates, several major changes in phase relationships occur during irradiation. Firstly, phases characteristic of remote regions of the phase diagram appear unexpectedly and dissolve during postirradiation annealing (radiation-induced phases). Secondly, some phases develop with their compositions significantly altered by the incorporation of Ni or Si (radiation-modified phases).

Lee, E.H.; Maziasz, P.J.; Rowcliffe, A.F.

1980-01-01T23:59:59.000Z

79

Microstructural Characterization of Irradiated U-7Mo/Al-5Si Dispersion to High Fission Density  

SciTech Connect (OSTI)

The fuel development program for research and test reactors calls for improved knowledge on the effect of microstructure on fuel performance in reactors. This work summarizes the recent TEM microstructural characterization of an irradiated U-7Mo/Al-5Si dispersion fuel plate (R3R050) irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory to 5.2×1021 fissions/cm3. While a large fraction of the fuel grains is decorated with large bubbles, there is no evidence showing interlinking of these large bubbles at the specified fission density. The attachment of solid fission product precipitates to the bubbles is likely the result of fission product diffusion into these bubbles. The process of fission gas bubble superlattice collapse appears through bubble coalescence. The results are compared with the previous TEM work of the dispersion fuels irradiated to lower fission density from the same fuel plate.

J. Gan; B. D. Miller; D. D. Keiser, Jr.; A. B. Robinson; J. W. Madden; P. G. Medvedev; D. M. Wachs

2014-11-01T23:59:59.000Z

80

Nonlinear Data Transformation with Diffusion Map  

E-Print Network [OSTI]

) Others: Laplacian eigenmaps, Hessian eigenmaps, LTSA We apply the diffusion map (Coifman & Lafon 2006

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


81

Correlation of Clinical and Dosimetric Factors With Adverse Pulmonary Outcomes in Children After Lung Irradiation  

SciTech Connect (OSTI)

Purpose: To identify the incidence and the risk factors for pulmonary toxicity in children treated for cancer with contemporary lung irradiation. Methods and Materials: We analyzed clinical features, radiographic findings, pulmonary function tests, and dosimetric parameters of children receiving irradiation to the lung fields over a 10-year period. Results: We identified 109 patients (75 male patients). The median age at irradiation was 13.8 years (range, 0.04-20.9 years). The median follow-up period was 3.4 years. The median prescribed radiation dose was 21 Gy (range, 0.4-64.8 Gy). Pulmonary toxic chemotherapy included bleomycin in 58.7% of patients and cyclophosphamide in 83.5%. The following pulmonary outcomes were identified and the 5-year cumulative incidence after irradiation was determined: pneumonitis, 6%; chronic cough, 10%; pneumonia, 35%; dyspnea, 11%; supplemental oxygen requirement, 2%; radiographic interstitial lung disease, 40%; and chest wall deformity, 12%. One patient died of progressive respiratory failure. Post-irradiation pulmonary function tests available from 44 patients showed evidence of obstructive lung disease (25%), restrictive disease (11%), hyperinflation (32%), and abnormal diffusion capacity (12%). Thoracic surgery, bleomycin, age, mean lung irradiation dose (MLD), maximum lung dose, prescribed dose, and dosimetric parameters between V{sub 22} (volume of lung exposed to a radiation dose ?22 Gy) and V{sub 30} (volume of lung exposed to a radiation dose ?30 Gy) were significant for the development of adverse pulmonary outcomes on univariate analysis. MLD, maximum lung dose, and V{sub dose} (percentage of volume of lung receiving the threshold dose or greater) were highly correlated. On multivariate analysis, MLD was the sole significant predictor of adverse pulmonary outcome (P=.01). Conclusions: Significant pulmonary dysfunction occurs in children receiving lung irradiation by contemporary techniques. MLD rather than prescribed dose should be used to perform risk stratification of patients receiving lung irradiation.

Venkatramani, Rajkumar, E-mail: rvenkatramani@chla.usc.edu [Division of Hematology/Oncology, Children's Hospital Los Angeles, Los Angeles, California (United States); Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, California (United States); Kamath, Sunil [Department of Pulmonology, Children's Hospital Los Angeles, Los Angeles, California (United States); Wong, Kenneth [Division of Hematology/Oncology, Children's Hospital Los Angeles, Los Angeles, California (United States); Olch, Arthur J. [Division of Hematology/Oncology, Children's Hospital Los Angeles, Los Angeles, California (United States); Department of Radiation Oncology, University of Southern California, Los Angeles, California (United States); Malvar, Jemily [Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California (United States); Sposto, Richard [Division of Hematology/Oncology, Children's Hospital Los Angeles, Los Angeles, California (United States); Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California (United States); Goodarzian, Fariba [Department of Radiology, Children's Hospital Los Angeles, Los Angeles, California (United States); Freyer, David R. [Division of Hematology/Oncology, Children's Hospital Los Angeles, Los Angeles, California (United States); Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, California (United States); Keens, Thomas G. [Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, California (United States); Department of Pulmonology, Children's Hospital Los Angeles, Los Angeles, California (United States); and others

2013-08-01T23:59:59.000Z

82

Low energy electron irradiation of an apple  

E-Print Network [OSTI]

The viability of pathogenic organisms on the surface of fresh fruits and vegetables can be significantly reduced by low energy electron beam irradiation. The most difficult technical challenge for surface irradiation of fruits and vegetable...

Brescia, Giovanni Batista

2002-01-01T23:59:59.000Z

83

Statistical criteria for characterizing irradiance time series.  

SciTech Connect (OSTI)

We propose and examine several statistical criteria for characterizing time series of solar irradiance. Time series of irradiance are used in analyses that seek to quantify the performance of photovoltaic (PV) power systems over time. Time series of irradiance are either measured or are simulated using models. Simulations of irradiance are often calibrated to or generated from statistics for observed irradiance and simulations are validated by comparing the simulation output to the observed irradiance. Criteria used in this comparison should derive from the context of the analyses in which the simulated irradiance is to be used. We examine three statistics that characterize time series and their use as criteria for comparing time series. We demonstrate these statistics using observed irradiance data recorded in August 2007 in Las Vegas, Nevada, and in June 2009 in Albuquerque, New Mexico.

Stein, Joshua S.; Ellis, Abraham; Hansen, Clifford W.

2010-10-01T23:59:59.000Z

84

X-ray spectroscopy study of electronic structure of laser-irradiated Au nanoparticles in a silica film  

SciTech Connect (OSTI)

The electronic structure of gold nanoparticles embedded in a silica film is studied, both before and after irradiation at 355 nm by a laser. The Au 5d occupied valence states are observed by x-ray emission spectroscopy. They show that before irradiation the gold atoms are in metallic states within the nanoparticles. After irradiation with a fluence of 0.5 J/cm{sup 2}, it is found that gold valence states are close to those of a metal-poor gold silicide; thanks to a comparison of the experimental Au 5d states with the calculated ones for gold silicides using the density-functional theory. The formation of such a compound is driven by the diffusion of the gold atoms into the silica film upon the laser irradiation. At higher fluence, 1 J/cm{sup 2}, we find a higher percentage of metallic gold that could be attributed to annealing in the silica matrix.

Jonnard, P.; Bercegol, H.; Lamaignere, L.; Morreeuw, J.-P.; Rullier, J.-L.; Cottancin, E.; Pellarin, M. [Laboratoire de Chimie Physique-Matiere et Rayonnement, Universite Pierre et Marie Curie, Centre National de la Recherche Scientifique Unite Mixte de Recherche (CNRS UMR) 7614, 11 rue Pierre et Marie Curie, F-75231 Paris Cedex 05 (France); Commissariat a l'Energie Atomique/Centre d'Etudes Scientifiques et Techniques d'Aquitaine (CEA/CESTA), BP 2, F-33114, Le Barp (France); Centre Agregat Laboratoire de Spectrometrie Ionique et Moleculaire (LASIM) et Laboratoire de Physique de la Matiere Condensee et Nanostructures (LPMCN), Universite Claude Bernard Lyon I, F-69622 Villeurbanne (France)

2005-03-15T23:59:59.000Z

85

Prediction of Room Air Diffusion for Reduced Diffuser Flow Rates  

E-Print Network [OSTI]

?, IEA Annex 20 project. The simulated results, in terms of maximum velocity, distribution of velocity and temperature in the room are validated against the experimental data. 3.1.1 Study the effect of various parameters on the CFD simulation. A study... and the walls of the room. The window is assumed to have a surface temperature of 30 0C.The diffuser used is a ?HESCO? type diffuser, which was used in the International Energy Agency (IEA) Annex 20 project (1993): ?Room air and contaminant flow, evaluation...

Gangisetti, Kavita

2011-02-22T23:59:59.000Z

86

3, 895959, 2006 Irradiance and  

E-Print Network [OSTI]

and corals. However, the contribution of benthic communities to the primary production of the global coastal energy source fueling marine primary prBGD 3, 895­959, 2006 Irradiance and primary production in the coastal ocean J.-P. Gattuso et al

Paris-Sud XI, Université de

87

sterilization by irradiation Arne Miller  

E-Print Network [OSTI]

-1:2006 Equipment characterization (6) Product definition (7) Process definition (8) Installation Qualification (9.1) Operational Qualification (9.2) · Performance Qualification (9.3) - later #12;3 Equipment characterization samples shall be irradiated to defined and uniform doses. #12;9 9.1 Installation qualification (A.9

88

Low temperature irradiation tests on  

E-Print Network [OSTI]

Sample cool down by He gas loop 10K ­ 20K Fast neutron flux Measured by Ni activation in 2010 1.4xK #12;reactor Cryogenics #12;Al-Cu-Mg He gas temperature near sample 12K Resistance changesLow temperature irradiation tests on stabilizer materials using reactor neutrons at KUR Makoto

McDonald, Kirk

89

Irradiation-induced phenomena in carbon  

E-Print Network [OSTI]

Chapter 1 Irradiation-induced phenomena in carbon nanotubes To appear in "Chemistry of Carbon@acclab.helsinki.fi 1 #12;2CHAPTER 1. IRRADIATION-INDUCED PHENOMENA IN CARBON NANOTUBES #12;Contents 1 Irradiation-induced phenomena in carbon nanotubes 1 1.1 Introduction

Krasheninnikov, Arkady V.

90

Transition from Irradiation-Induced Amorphization to Crystallization...  

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

from Irradiation-Induced Amorphization to Crystallization in Nanocrystalline Silicon Carbide. Transition from Irradiation-Induced Amorphization to Crystallization in...

91

Occlusion-Aware Hessians for Error Control in Irradiance Caching /  

E-Print Network [OSTI]

Control for Irradiance Caching. ” In ACM Transactions on Graphics,Control for Irradiance Caching. ” In ACM Transactions on Graphics,

Schwarzhaupt, Jorge Andres

2013-01-01T23:59:59.000Z

92

Beta Diffusion Trees Creighton Heaukulani  

E-Print Network [OSTI]

Beta Diffusion Trees Creighton Heaukulani CKH28@CAM.AC.UK David A. Knowles DAVIDKNOWLES Stanford University, Department of Computer Science, Stanford, CA, USA Abstract We define the beta structures over clusters of the particles. With the beta diffu- sion tree, however, multiple copies

Edinburgh, University of

93

GTL-1 Irradiation Summary Report  

SciTech Connect (OSTI)

The primary objective of the Gas Test Loop (GTL-1) miniplate experiment is to confirm acceptable performance of high-density (i.e., 4.8 g-U/cm3) U3Si2/Al dispersion fuel plates clad in Al-6061 and irradiated under the relatively aggressive Booster Fast Flux Loop (BFFL) booster fuel conditions, namely a peak plate surface heat flux of 450 W/cm2. As secondary objectives, several design and fabrication variations were included in the test matrix that may have the potential to improve the high-heat flux, high-temperature performance of the base fuel plate design.1, 2 The following report summarizes the life of the GTL-1 experiment through end of irradiation, including as-run neutronic analysis, thermal analysis and hydraulic testing results.

D. M. Perez; G. S. Chang; N. E. Woolstenhulme; D. M. Wachs

2012-01-01T23:59:59.000Z

94

Radiation effects on microstructures and properties of irradiated materials  

SciTech Connect (OSTI)

Development of structural materials to withstand aggressive radiation environments has been carried out on an international scale over the past four decades. Major radiation-induced changes in properties include swelling, creep and embrittlement. The basic work, stimulated by technology, to understand and control these phenomena, has been heavily oriented toward the evolution of microstructures and their effects on properties. Microstructural research has coupled analyses by high resolution techniques with theoretical modeling to describe and predict microscopic features and the resulting macroscopic properties. A short summary is presented of key physical considerations that drive these changes during irradiation. Such processes begin with displacement cascades, and lead to property changes through the diffusion and clustering of defects.

Mansur, L.K.

1996-12-01T23:59:59.000Z

95

TEMPERATURE DEPENDANT BEHAVIOUR OBSERVED IN THE AFIP-6 IRRADIATION TEST  

SciTech Connect (OSTI)

The AFIP-6 test assembly was irradiated for one cycle in the Advanced Test Reactor at Idaho National Laboratory. The experiment was designed to test two monolithic fuel plates at power and burn-ups which bounded the operating conditions of both ATR and HFIR driver fuel. Both plates contained a solid U-Mo fuel foil with a zirconium diffusion barrier between 6061-aluminum cladding plates bonded by hot isostatic pressing. The experiment was designed with an orifice to restrict the coolant flow in order to obtain prototypic coolant temperature conditions. While these coolant temperatures were obtained, the reduced flow resulted in a sufficiently low heat transfer coefficient that failure of the fuel plates occurred. The increased fuel temperature led to significant variations in the fission gas retention behaviour of the U-Mo fuel. These variations in performance are outlined herein.

A. B. Robinson; D. M. Wachs; P. Medvedev; S.J. Miller; F. J. Rice; M. K. Meyer; D. M. Perez

2012-03-01T23:59:59.000Z

96

Optically Thick Outflows of Supercritical Accretion Discs: Radiative Diffusion Approach  

E-Print Network [OSTI]

Highly supercritical accretion discs are probable sources of dense optically thick axisymmetric winds. We introduce a new approach based on diffusion approximation radiative transfer in a funnel geometry and obtain an analytical solution for the energy density distribution inside the wind assuming that all the mass, momentum and energy are injected well inside the spherization radius. This allows to derive the spectrum of emergent emission for various inclination angles. We show that self-irradiation effects play an important role altering the temperature of the outcoming radiation by about 20% and the apparent X-ray luminosity by a factor of 2-3. The model has been successfully applied to two ULXs. The basic properties of the high ionization HII-regions found around some ULXs are also easily reproduced in our assumptions.

P. Abolmasov; S. Karpov; Taro Kotani

2008-09-04T23:59:59.000Z

97

RERTR-6 Irradiation Summary Report  

SciTech Connect (OSTI)

The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-6 was designed to evaluate several modified fuel designs that were proposed to address the possibility of breakaway swelling due to porosity within the (U. Mo) Al interaction product observed in the full-size plate tests performed in Russia and France1. The following report summarizes the life of the RERTR-6 experiment through end of irradiation, including as-run neutronic analyses, thermal analyses and hydraulic testing results.

D. M. Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

2011-12-01T23:59:59.000Z

98

RERTR-13 Irradiation Summary Report  

SciTech Connect (OSTI)

The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-13 was designed to assess performance of different types of neutron absorbers that can be potentially used as burnable poisons in the low enriched uranium-molybdenum based dispersion and monolithic fuels.1 The following report summarizes the life of the RERTR-13 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

D. M. Perez; M. A. Lillo; G. S. Chang; D. M. Wachs; G. A. Roth; N. E. Woolstenhulme

2012-09-01T23:59:59.000Z

99

Nuclear plant irradiated steel handbook  

SciTech Connect (OSTI)

This reference handbook presents selected information extracted from the EPRI reactor surveillance program database, which contains the results from surveillance program reports on 57 plants and 116 capsules. Tabulated data includes radiation induced temperature shifts, capsule irradiation conditions and statistical features of the Charpy V-notch curves. General information on the surveillance materials is provided and the Charpy V-notch energy results are presented graphically.

Oldfield, W.; Oldfield, F.M.; Lombrozo, P.M.; McConnell, P.

1986-09-01T23:59:59.000Z

100

Absorption of intradermally injected horse gamma globulin, a foreign protein, in rabbits following whole body gamma irradiation  

E-Print Network [OSTI]

into an X-irradiated area. 5 Levy has studied the effect of X-irradiation on localization of Evans Blue dye. These authors concluded that dye spread is directly related to the radiation induced increase in vascular permeability. 6 Glenn, Kahn... quantitative study of a technique of double diffusion in agar. J. Immun. 77:52-60 (1956). 17. Clemedson, C. J. and A. Nelson. Mechanisms in radiobiology, Vol. 2, pp. 152-6, Academic Press, New York (1960). 18. Caster, W. D. Effect of X-rays...

Pryor, William Harold

1965-01-01T23:59:59.000Z

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


101

Determination of ion track radii in amorphous matrices via formation of nano-clusters by ion-beam irradiation  

SciTech Connect (OSTI)

We report on a method for the determination of ion track radii, formed in amorphous materials by ion-beam irradiation. The method is based on the addition to an amorphous matrix of a small amount of foreign atoms, which easily diffuse and form clusters when the temperature is sufficiently increased. The irradiation causes clustering of these atoms, and the final separations of the formed clusters are dependent on the parameters of the ion-beam. Comparison of the separations between the clusters that are formed by ions with different properties in the same type of material enables the determination of ion-track radii.

Buljan, M.; Karlusic, M.; Bogdanovic-Radovic, I.; Jaksic, M.; Radic, N. [Rudjer Boskovic Institute, Bijenicka cesta 54, 10000 Zagreb (Croatia); Salamon, K. [Institute of Physics, 10000 Zagreb (Croatia); Bernstorff, S. [Sincrotrone Trieste, 34102 Basovizza (Italy)

2012-09-03T23:59:59.000Z

102

Sandia National Laboratories: Diffusion Bonding Characterization  

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

bond surface is poor or only the region near this corner Diffusion 7-8-9 Diffusion Welding and Brazing, Welding Handbook, 7th ed., American Welding Society, 1980, p 311-335...

103

MICROFLUIDIC CONTROL OF STEM CELL DIFFUSIBLE SIGNALING  

E-Print Network [OSTI]

MICROFLUIDIC CONTROL OF STEM CELL DIFFUSIBLE SIGNALING Katarina Blagovi, Lily Y. Kim, Alison M cell differentiation. KEYWORDS: Embryonic stem cells, microfluidic perfusion, diffusible signaling; they secrete molecules to which they respond. Microfluidics offers a potential solution to this challenge

Voldman, Joel

104

OXYGEN DIFFUSION IN UO2-x  

E-Print Network [OSTI]

~ K.C. K:i.m, "Oxygen Diffusion in Hypostoichiometricsystem for enriching uo 2 in oxygen-18 or for stoichiometry+nal of Nuclear Materials OXYGEN DIFFUSION IN U0 2 _:x K.C.

Kim, K.C.

2013-01-01T23:59:59.000Z

105

Synergistic diffuser/heat-exchanger design  

E-Print Network [OSTI]

The theoretical and numerical evaluation of synergistic diffusing heat-exchanger design is presented. Motivation for this development is based on current diffuser and heat-exchange technologies in cogeneration plants, which ...

Lazzara, David S. (David Sergio), 1980-

2004-01-01T23:59:59.000Z

106

Hierarchical 3D diffusion wavelet shape priors  

E-Print Network [OSTI]

In this paper, we propose a novel representation of prior knowledge for image segmentation, using diffusion wavelets that can reflect arbitrary continuous interdependencies in shape data. The application of diffusion ...

Langs, Georg

107

Heat Hyperbolic Diffusion in Planck Gas  

E-Print Network [OSTI]

In this paper we investigate the diffusion of the thermal pulse in Planck Gas. We show that the Fourier diffusion equation gives the speed of diffusion, v > c and breaks the causality of the thermal processes in Planck gas .For hyperbolic heat transport v

Miroslaw Kozlowski; Janina Marciak-Kozlowska

2006-07-06T23:59:59.000Z

108

EPR Investigation of Irradiated Curry Powder  

SciTech Connect (OSTI)

Gamma-ray irradiated curry powder, a well priced oriental spice was investigated in order to establish the ability of EPR to detect the presence and time stability of free irradiation free-radicals. Accordingly, curry powder aliquots were irradiated with gradually increasing absorbed doses up to 11.3 kGy. The EPR spectra of all irradiated samples show the presence of al last two different species of free radicals, whose concentration increased monotonously with the absorbed doses. A 100 deg. C isothermal annealing of irradiated samples has shown a differential reduction of amplitude of various components of the initial spectra, but even after 3.6 h of thermal treatment, the remaining amplitude represents no less then 30% of the initial ones. The same peculiarities have been noticed after more than one year storage at room temperature, all of them being very useful in establishing the existence of any previous irradiation treatment.

Duliu, O. G.; Ali, S. I. [University of Bucharest, Department of Atomic and Nuclear Physics, P.O. Box MG-11, 077125 Bucharest (Romania); Georgescu, R. [National Institute for Physics and Nuclear Engineering-Horia Hulubei, P.O. Box MG-6, 077125 Bucharest (Romania)

2007-04-23T23:59:59.000Z

109

Service Promotion -Diffusion Raphale LOMBARD  

E-Print Network [OSTI]

Service Promotion - Diffusion Raphaële LOMBARD Editions L'Harmattan - 5 Rue de l'Ecole Polytechnique ­ 75005 Paris Tél 01.40.46.79.23 ­ mail : raphaele.lombard@harmattan.fr La mondialisation avance à complémentaires BON DE COMMANDE A retourner à L'HARMATTAN, 7 rue de l'�cole Polytechnique 75005 Paris Veuillez me

Pellier, Damien

110

Void Nucleation, Growth and Coalescence in Irradiated Metals  

SciTech Connect (OSTI)

A novel computational treatment of dense, stiff, coupled reaction rate equations is introduced to study the nucleation, growth, and possible coalescence of cavities during neutron irradiation of metals. Radiation damage is modeled by the creation of Frenkel pair defects and helium impurity atoms. A multi-dimensional cluster size distribution function allows independent evolution of the vacancy and helium content of cavities, distinguishing voids and bubbles. A model with sessile cavities and no cluster-cluster coalescence can result in a bimodal final cavity size distribution with coexistence of small, high-pressure bubbles and large, low-pressure voids. A model that includes unhindered cavity diffusion and coalescence ultimately removes the small helium bubbles from the system, leaving only large voids. The terminal void density is also reduced and the incubation period and terminal swelling rate can be greatly altered by cavity coalescence. Temperature-dependent trapping of voids/bubbles by precipitates and alterations in void surface diffusion from adsorbed impurities and internal gas pressure may give rise to intermediate swelling behavior through their effects on cavity mobility and coalescence.

Surh, M P; Sturgeon, J B; Wolfer, W G

2008-01-11T23:59:59.000Z

111

Crystal defect studies using x-ray diffuse scattering  

SciTech Connect (OSTI)

Microscopic lattice defects such as point (single atom) defects, dislocation loops, and solute precipitates are characterized by local electronic density changes at the defect sites and by distortions of the lattice structure surrounding the defects. The effect of these interruptions of the crystal lattice on the scattering of x-rays is considered in this paper, and examples are presented of the use of the diffuse scattering to study the defects. X-ray studies of self-interstitials in electron irradiated aluminum and copper are discussed in terms of the identification of the interstitial configuration. Methods for detecting the onset of point defect aggregation into dislocation loops are considered and new techniques for the determination of separate size distributions for vacancy loops and interstitial loops are presented. Direct comparisons of dislocation loop measurements by x-rays with existing electron microscopy studies of dislocation loops indicate agreement for larger size loops, but x-ray measurements report higher concentrations in the smaller loop range. Methods for distinguishing between loops and three-dimensional precipitates are discussed and possibilities for detailed studies considered. A comparison of dislocation loop size distributions obtained from integral diffuse scattering measurements with those from TEM show a discrepancy in the smaller sizes similar to that described above.

Larson, B.C.

1980-01-01T23:59:59.000Z

112

Sodium and potassium levels in the serum of acutely irradiated and non-irradiated rats  

E-Print Network [OSTI]

SODIUM AND POTASSIUM LEVELS IN THE SERUM OF ACUTELY IRRADIATED AND NON-IRRADIATED RATS A Thesis By DAVID PRESTON SHEPHERD Submitted to the Graduate College of the Texas ARM University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE August 1967 Major Subject: Zoology SODIUM AND POTASSIUM LEVELS IN THE SERUM OF ACUTELY IRRADIATED AND NON-IRRADIATED RATS A Thesis By DAVID PRESTON SHEPHERD Approved as to style and content by: (Chairman of Committee) (Head...

Shepherd, David Preston

1967-01-01T23:59:59.000Z

113

Group classification of systems of non-linear reaction-diffusion equations with general diffusion matrix. II. Generalized Turing systems  

E-Print Network [OSTI]

Group classification of systems of two coupled nonlinear reaction-diffusion equation with a diagonal diffusion matrix is carried out. Symmetries of diffusion systems with singular diffusion matrix and additional first order derivative terms are described.

A. G. Nikitin

2007-07-20T23:59:59.000Z

114

Nuclear Engineering Division Irradiated Materials Laboratory  

E-Print Network [OSTI]

Nuclear Engineering Division Irradiated Materials Laboratory The Irradiated Materials Laboratory (IML) in Argonne's Nuclear Engineering Division is used to conduct research on the behavior. #12;C O N TA C T > Dr. Michael C. Billone | 630-252-7146 | billone@anl.gov | Nuclear Engineering

Kemner, Ken

115

Phase formation in Zr/Fe multilayers during Kr ion irradiation.  

SciTech Connect (OSTI)

A detailed study has been conducted of the effect of Kr ion irradiation on phase formation in Zr-Fe metallic multilayers, using the Intermediate Voltage Electron Microscopy (IVEM) at Argonne National Laboratory. Metallic multilayers were prepared with different overall compositions (near 50-50 and Fe-rich), and with different wavelengths (repetition thicknesses). These samples were irradiated with 300 keV Kr ions at various temperatures to investigate the final products, as well as the kinetics of phase formation. For the shorter wavelength samples, the final product was in all cases an amorphous Zr-Fe phase, in combination with Fe, while specially for the larger wavelength samples, in the Fe-rich samples the intermetallic compounds ZrFe{sub 2} and Zr{sub 3}Fe were formed in addition to the amorphous phase. The dose to full reaction decreases with temperature, and with wavelength in a manner consistent with a diffusion-controlled reaction.

Motta, A. T.

1998-01-29T23:59:59.000Z

116

Summary of Post Irradiation Examination Results of the AFIP-6 Failure  

SciTech Connect (OSTI)

The AFIP-6 test assembly was irradiated for one cycle in the Advanced Test Reactor at Idaho National Laboratory. The experiment was designed to test two monolithic fuel plates at power and burn-ups which bounded the operating conditions of both ATR and HFIR driver fuel. Both plates contain a solid U-Mo fuel foil with a zirconium diffusion barrier between 6061-aluminum cladding plates bonded by hot isostatic pressing. The experiment was designed with an orifice to restrict the coolant flow in order to obtain prototypic coolant temperature conditions. While these coolant temperatures were obtained, flow restriction resulted in low heat transfer coefficients and the failure of the fuel plates. The results from the post irradiation examinations and some observations of the failure mechanisms are outlined herein.

Adam Robinson; Daniel M. Wachs; Francine Rice; Danielle Perez

2011-10-01T23:59:59.000Z

117

Initial increase, ''peaking effect'', in the internal friction of copper following pulsed neutron and electron irradiation  

SciTech Connect (OSTI)

Under certain experimental conditions the internal friction in metals can first increase and following prolonged irradiation decrease. Many models have been proposed to account for this ''peaking effect''; however, in many of the cases, no effort is made to distinguish between the influence of interstitials and/or vacancies. To determine the nature of the point defect responsible for the peaking effect in high purity copper, we have performed a series of pulsed irradiations using neutrons and electrons. In all of the experiments an initial very rapid rise in the internal friction and Young's modulus was observed. These data show that a fast diffusing defect is responsible for the peaking effect: i.e. the interstitial.

Simpson, H.M.; Parkin, D.M.; Goldstone, J.A.; Hemsky, J.W.

1985-01-01T23:59:59.000Z

118

AGC-1 Irradiation Experiment Test Plan  

SciTech Connect (OSTI)

The Advanced Graphite Capsule (AGC) irradiation test program supports the acquisition of irradiated graphite performance data to assist in the selection of the technology to be used for the VHTR. Six irradiations are planned to investigate compressive creep in graphite subjected to a neutron field and obtain irradiated mechanical properties of vibrationally molded, extruded, and iso-molded graphites for comparison. The experiments will be conducted at three temperatures: 600, 900, and 1200°C. At each temperature, two different capsules will be irradiated to different fluence levels, the first from 0.5 to 4 dpa and the second from 4 to 7 dpa. AGC-1 is the first of the six capsules designed for ATR and will focus on the prismatic fluence range.

R. L. Bratton

2006-05-01T23:59:59.000Z

119

Irradiation-induced defect clustering and amorphization in silicon...  

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

Irradiation-induced defect clustering and amorphization in silicon carbide. Irradiation-induced defect clustering and amorphization in silicon carbide. Abstract: Previous computer...

120

Neutron Irradiation of Hydrided Cladding Material in HFIR Summary...  

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

Neutron Irradiation of Hydrided Cladding Material in HFIR Summary of Initial Activities Neutron Irradiation of Hydrided Cladding Material in HFIR Summary of Initial Activities...

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


121

Magnetization measurements and XMCD studies on ion irradiated...  

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

measurements and XMCD studies on ion irradiated iron oxide and core-shell ironiron-oxide nanomaterials. Magnetization measurements and XMCD studies on ion irradiated iron oxide...

122

RERTR-7 Irradiation Summary Report  

SciTech Connect (OSTI)

The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-7A, was designed to test several modified fuel designs to target fission densities representative of a peak low enriched uranium (LEU) burnup in excess of 90% U-235 at peak experiment power sufficient to generate a peak surface heat flux of approximately 300 W/cm2. The RERTR-7B experiment was designed as a high power test of 'second generation' dispersion fuels at peak experiment power sufficient to generate a surface heat flux on the order of 230 W/cm2.1 The following report summarizes the life of the RERTR-7A and RERTR-7B experiments through end of irradiation, including as-run neutronic analyses, thermal analyses and hydraulic testing results.

D. M. Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

2011-12-01T23:59:59.000Z

123

Diffusion processes in general relativistic radiating spheres  

SciTech Connect (OSTI)

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.

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

1989-09-01T23:59:59.000Z

124

Characterizing unsaturated diffusion in porous tuff gravel  

SciTech Connect (OSTI)

Evaluation of solute diffusion in unsaturated porous gravel is very important for investigations of contaminant transport and remediation, risk assessment, and waste disposal (for example, the potential high-level nuclear waste repository at Yucca Mountain, Nevada). For a porous aggregate medium such as granular tuff, the total water content is comprised of surface water and interior water. The surface water component (water film around grains and pendular water between the grain contacts) could serve as a predominant diffusion pathway. To investigate the extent to which surface water films and contact points affect solute diffusion in unsaturated gravel, we examined the configuration of water using x-ray computed tomography in partially saturated gravel, and made quantitative measurements of diffusion at multiple water contents using two different techniques. In the first, diffusion coefficients of potassium chloride in 2-4 mm granular tuff at multiple water contents were calculated from electrical conductivity measurements using the Nernst-Einstein equation. In the second, we used laser ablation with inductively coupled plasma-mass spectrometry to perform micro-scale mapping, allowing the measurement of diffusion coefficients for a mixture of chemical tracers for tuff cubes and tetrahedrons having two contact geometries (cube-cube and cube-tetrahedron). The x-ray computed tomography images show limited contact between grains, and this could hinder the pathways for diffusive transport. Experimental results show the critical role of surface water in controlling transport pathways and hence the magnitude of diffusion. Even with a bulk volumetric water content of 1.5%, the measured solute diffusion coefficient is as low as 1.5 x 10{sup -14} m{sup 2}/s for tuff gravel. Currently used diffusion models relating diffusion coefficients to total volumetric water content inadequately describe unsaturated diffusion behavior in porous gravel at very low water contents.

Hu, Qinhong; Kneafsey, Timothy J.; Roberts, Jeffery J.; Tomutsa, Liviu; Wang, Joseph, S.Y.

2003-11-12T23:59:59.000Z

125

Lamp system with conditioned water coolant and diffuse reflector of polytetrafluorethylene(PTFE)  

DOE Patents [OSTI]

A lamp system with a very soft high-intensity output is provided over a large area by water cooling a long-arc lamp inside a diffuse reflector of polytetrafluorethylene (PTFE) and titanium dioxide (TiO.sub.2) white pigment. The water is kept clean and pure by a one micron particulate filter and an activated charcoal/ultraviolet irradiation system that circulates and de-ionizes and biologically sterilizes the coolant water at all times, even when the long-arc lamp is off.

Zapata, Luis E. (Livermore, CA); Hackel, Lloyd (Livermore, CA)

1999-01-01T23:59:59.000Z

126

Comparison of fission product release predictions using PARFUME with results from the AGR-1 irradiation experiment  

SciTech Connect (OSTI)

This report documents comparisons between post-irradiation examination measurements and model predictions of silver (Ag), cesium (Cs), and strontium (Sr) release from selected tristructural isotropic (TRISO) fuel particles and compacts during the first irradiation test of the Advanced Gas Reactor program that occurred from December 2006 to November 2009 in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). The modeling was performed using the particle fuel model computer code PARFUME (PARticle FUel ModEl) developed at INL. PARFUME is an advanced gas-cooled reactor fuel performance modeling and analysis code (Miller 2009). It has been developed as an integrated mechanistic code that evaluates the thermal, mechanical, and physico-chemical behavior of fuel particles during irradiation to determine the failure probability of a population of fuel particles given the particle-to-particle statistical variations in physical dimensions and material properties that arise from the fuel fabrication process, accounting for all viable mechanisms that can lead to particle failure. The code also determines the diffusion of fission products from the fuel through the particle coating layers, and through the fuel matrix to the coolant boundary. The subsequent release of fission products is calculated at the compact level (release of fission products from the compact) but it can be assessed at the particle level by adjusting the diffusivity in the fuel matrix to very high values. Furthermore, the diffusivity of each layer can be individually set to a high value (typically 10-6 m2/s) to simulate a failed layer with no capability of fission product retention. In this study, the comparison to PIE focused on fission product release and because of the lack of failure in the irradiation, the probability of particle failure was not calculated. During the AGR-1 irradiation campaign, the fuel kernel produced and released fission products, which migrated through the successive layers of the TRISO-coated particle and potentially through the compact matrix. The release of these fission products was measured in PIE and modeled with PARFUME.

Blaise Collin

2014-09-01T23:59:59.000Z

127

Solar Irradiances Measured using SPN1 Radiometers: Uncertainties and Clues for Development  

SciTech Connect (OSTI)

The fast development of solar radiation and energy applications, such as photovoltaic and solar thermodynamic systems, has increased the need for solar radiation measurement and monitoring, not only for the global component but also the diffuse and direct. End users look for the best compromise between getting close to state-of-the-art measurements and keeping capital, maintenance and operating costs to a minimum. Among the existing commercial options, SPN1 is a relatively low cost solar radiometer that estimates global and diffuse solar irradiances from seven thermopile sensors under a shading mask and without moving parts. This work presents a comprehensive study of SPN1 accuracy and sources of uncertainty, which results from laboratory experiments, numerical modeling and comparison studies between measurements from this sensor and state-of-the art instruments for six diverse sites. Several clues are provided for improving the SPN1 accuracy and agreement with state-of-the-art measurements.

Badosa, Jordi; Wood, John; Blanc, Philippe; Long, Charles N.; Vuilleumier, Laurent; Demengel, Dominique; Haeffelin, Martial

2014-12-08T23:59:59.000Z

128

Self-Similar Modes of Coherent Diffusion  

E-Print Network [OSTI]

Self-similar solutions of the coherent diffusion equation are derived and measured. The set of real similarity solutions is generalized by the introduction of a nonuniform phase surface, based on the elegant Gaussian modes of optical diffraction. In an experiment of light storage in a gas of diffusing atoms, a complex initial condition is imprinted, and its diffusion dynamics is monitored. The self-similarity of both the amplitude and the phase pattern is demonstrated, and an algebraic decay associated with the mode order is measured. Notably, as opposed to a regular diffusion spreading, a self-similar contraction of a special subset of the solutions is predicted and observed.

O. Firstenberg; P. London; D. Yankelev; R. Pugatch; M. Shuker; N. Davidson

2010-08-16T23:59:59.000Z

129

Enforcement Documents - Portsmouth Gaseous Diffusion Plant |...  

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

Gaseous Diffusion Plant March 26, 2010 Enforcement Letter, Geiger Brothers Mechanical Contractors, INC - March 26, 2010 Issued to Geiger Brothers Mechanical Contractors,...

130

Independent Activity Report, Portsmouth Gaseous Diffusion Plant...  

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

2011 August 2011 Orientation Visit to the Portsmouth Gaseous Diffusion Plant HIAR-PORTS-2011-08-03 This Independent Activity Report documents an operational awareness...

131

AGC-1 Post Irradiation Examination Status  

SciTech Connect (OSTI)

The Next Generation Nuclear Plant (NGNP) Graphite R&D program is currently measuring irradiated material property changes in several grades of nuclear graphite for predicting their behavior and operating performance within the core of new Very High Temperature Reactor (VHTR) designs. The Advanced Graphite Creep (AGC) experiment consisting of six irradiation capsules will generate this irradiated graphite performance data for NGNP reactor operating conditions. All six AGC capsules in the experiment will be irradiated in the Advanced Test Reactor (ATR), disassembled in the Hot Fuel Examination Facility (HFEF), and examined at the INL Research Center (IRC) or Oak Ridge National Laboratory (ORNL). This is the first in a series of status reports on the progress of the AGC experiment. As the first capsule, AGC1 was irradiated from September 2009 to January 2011 to a maximum dose level of 6-7 dpa. The capsule was removed from ATR and transferred to the HFEF in April 2011 where the capsule was disassembled and test specimens extracted from the capsules. The first irradiated samples from AGC1 were shipped to the IRC in July 2011and initial post irradiation examination (PIE) activities were begun on the first 37 samples received. PIE activities continue for the remainder of the AGC1 specimen as they are received at the IRC.

David Swank

2011-09-01T23:59:59.000Z

132

AGR-1 Irradiation Experiment Test Plan  

SciTech Connect (OSTI)

This document presents the current state of planning for the AGR-1 irradiation experiment, the first of eight planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. The objectives of the AGR-1 experiment are: 1. To gain experience with multi-capsule test train design, fabrication, and operation with the intent to reduce the probability of capsule or test train failure in subsequent irradiation tests. 2. To irradiate fuel produced in conjunction with the AGR fuel process development effort. 3. To provide data that will support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. In order to achieve the test objectives, the AGR-1 experiment will be irradiated in the B-10 position of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). The test will contain six independently controlled and monitored capsules. Each capsule will contain a single type, or variant, of the AGR coated fuel. The irradiation is planned for about 700 effective full power days (approximately 2.4 calendar years) with a time-averaged, volume-average temperature of approximately 1050 °C. Average fuel burnup, for the entire test, will be greater than 17.7 % FIMA, and the fuel will experience fast neutron fluences between 2.4 and 4.5 x 1025 n/m2 (E>0.18 MeV).

John T. Maki

2009-10-01T23:59:59.000Z

133

RERTR-12 Insertion 2 Irradiation Summary Report  

SciTech Connect (OSTI)

The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-12 was designed to provide comprehensive information on the performance of uranium-molybdenum (U-Mo) based monolithic fuels for research reactor applications.1 RERTR-12 insertion 2 includes the capsules irradiated during the last three irradiation cycles. These capsules include Z, Y1, Y2 and Y3 type capsules. The following report summarizes the life of the RERTR-12 insertion 2 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

D. M. Perez; G. S. Chang; D. M. Wachs; G. A. Roth; N. E. Woolstenhulme

2012-09-01T23:59:59.000Z

134

Measuring Degradation Rates Without Irradiance Data  

SciTech Connect (OSTI)

A method to report PV system degradation rates without using irradiance data is demonstrated. First, a set of relative degradation rates are determined by comparing daily AC final yields from a group of PV systems relative to the average final yield of all the PV systems. Then, the difference between relative and absolute degradation rates is found from a statistical analysis. This approach is verified by comparing to methods that utilize irradiance data. This approach is significant because PV systems are often deployed without irradiance sensors, so the analysis method described here may enable measurements of degradation using data that were previously thought to be unsuitable for degradation studies.

Pulver, S.; Cormode, D.; Cronin, A.; Jordan, D.; Kurtz, S.; Smith, R.

2011-02-01T23:59:59.000Z

135

Modelling international wind energy diffusion: Are the patterns of induced diffusion `S'  

E-Print Network [OSTI]

Modelling international wind energy diffusion: Are the patterns of induced diffusion `S' shaped datasets, the paper explores the patterns of international wind energy diffusion in OECD countries. The model employed in the paper predicted that wind energy, as a complex and expensive innovation, would

Feigon, Brooke

136

Finite-difference schemes for anisotropic diffusion  

SciTech Connect (OSTI)

In fusion plasmas diffusion tensors are extremely anisotropic due to the high temperature and large magnetic field strength. This causes diffusion, heat conduction, and viscous momentum loss, to effectively be aligned with the magnetic field lines. This alignment leads to different values for the respective diffusive coefficients in the magnetic field direction and in the perpendicular direction, to the extent that heat diffusion coefficients can be up to 10{sup 12} times larger in the parallel direction than in the perpendicular direction. This anisotropy puts stringent requirements on the numerical methods used to approximate the MHD-equations since any misalignment of the grid may cause the perpendicular diffusion to be polluted by the numerical error in approximating the parallel diffusion. Currently the common approach is to apply magnetic field-aligned coordinates, an approach that automatically takes care of the directionality of the diffusive coefficients. This approach runs into problems at x-points and at points where there is magnetic re-connection, since this causes local non-alignment. It is therefore useful to consider numerical schemes that are tolerant to the misalignment of the grid with the magnetic field lines, both to improve existing methods and to help open the possibility of applying regular non-aligned grids. To investigate this, in this paper several discretization schemes are developed and applied to the anisotropic heat diffusion equation on a non-aligned grid.

Es, Bram van, E-mail: es@cwi.nl [Centrum Wiskunde and Informatica, P.O. Box 94079, 1090GB Amsterdam (Netherlands); FOM Institute DIFFER, Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM (Netherlands); Koren, Barry [Eindhoven University of Technology (Netherlands); Blank, Hugo J. de [FOM Institute DIFFER, Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM (Netherlands)

2014-09-01T23:59:59.000Z

137

CONVERTIBLE BONDS IN A DEFAULTABLE DIFFUSION MODEL  

E-Print Network [OSTI]

CONVERTIBLE BONDS IN A DEFAULTABLE DIFFUSION MODEL Tomasz R. Bielecki Department of Applied Research Grant PS12918. #12;2 Convertible Bonds in a Defaultable Diffusion Model 1 Introduction In [4), such as Convertible Bonds (CB), and we provided a rigorous decomposition of a CB into a bond component and a (game

Jeanblanc, Monique

138

ON DIFFUSION IN HETEROGENEOUS MEDIA YOUXUE ZHANG*,  

E-Print Network [OSTI]

, heterogeneous media, multi-mineral rocks, multi-phase media, composite materials, kinetics, porous rocks to bulk diffusion, and porous materials (such as plants, soil, rock with partial melt or fluid, sediment of air and moisture in soils, drying of paint, wood, and concrete, diffusion of gases in rubber, movement

Liu, Liping

139

ANISOTROPIC DIFFUSION USING POWER WATERSHEDS Camille Couprie  

E-Print Network [OSTI]

optimal methods such as graph cuts have received a lot of attention. However not all problems in com are able to optimize this energy quickly and effectively. This study paves the way for using the power and the diffusion time. Practical usage of anisotropic diffusion requires a choice between long compu- tation times

Paris-Sud XI, Université de

140

Surveying Diffusion in Complex Geometries. An Essay  

E-Print Network [OSTI]

The surrounding world surprises us by the beauty and variety of complex shapes that emerge from nanometric to macroscopic scales. Natural or manufactured materials (sandstones, sedimentary rocks and cement), colloidal solutions (proteins and DNA), biological cells, tissues and organs (lungs, kidneys and placenta), they all present irregularly shaped "scenes" for a fundamental transport "performance", that is, diffusion. Here, the geometrical complexity, entangled with the stochastic character of diffusive motion, results in numerous fascinating and sometimes unexpected effects like diffusion screening or localization. These effects control many diffusion-mediated processes that play an important role in heterogeneous catalysis, biochemical mechanisms, electrochemistry, growth phenomena, oil recovery, or building industry. In spite of a long and rich history of academic and industrial research in this field, it is striking to see how little we know about diffusion in complex geometries, especially the one which occurs in three dimensions. We present our recent results on restricted diffusion. We look into the role of geometrical complexity at different levels, from boundary microroughness to hierarchical structure and connectivity of the whole diffusion-confining domain. We develop a new approach which consists in combining fast random walk algorithms with spectral tools. The main focus is on studying diffusion in model complex geometries (von Koch boundaries, Kitaoka acinus, etc.), as well as on developing and testing spectral methods. We aim at extending this knowledge and at applying the accomplished arsenal of theoretical and numerical tools to structures found in nature and industry.

Denis Grebenkov

2009-09-08T23:59:59.000Z

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


141

Diffusive limit for the random Lorentz gas  

E-Print Network [OSTI]

We review some recent results concerning the derivation of the diffusion equation and the validation of Fick's law for the microscopic model given by the random Lorentz Gas. These results are achieved by using a linear kinetic equation as an intermediate level of description between our original mechanical system and the diffusion equation.

Alessia Nota

2014-10-14T23:59:59.000Z

142

Inverse diffusion from knowledge of power densities  

E-Print Network [OSTI]

This paper concerns the reconstruction of a diffusion coefficient in an elliptic equation from knowledge of several power densities. The power density is the product of the diffusion coefficient with the square of the modulus of the gradient of the elliptic solution. The derivation of such internal functionals comes from perturbing the medium of interest by acoustic (plane) waves, which results in small changes in the diffusion coefficient. After appropriate asymptotic expansions and (Fourier) transformation, this allow us to construct the power density of the equation point-wise inside the domain. Such a setting finds applications in ultrasound modulated electrical impedance tomography and ultrasound modulated optical tomography. We show that the diffusion coefficient can be uniquely and stably reconstructed from knowledge of a sufficient large number of power densities. Explicit expressions for the reconstruction of the diffusion coefficient are also provided. Such results hold for a large class of boundary...

Bal, Guillaume; Monard, Francois; Triki, Faouzi

2011-01-01T23:59:59.000Z

143

Surveying Diffusion in Complex Geometries. An Essay  

E-Print Network [OSTI]

The surrounding world surprises us by the beauty and variety of complex shapes that emerge from nanometric to macroscopic scales. Natural or manufactured materials (sandstones, sedimentary rocks and cement), colloidal solutions (proteins and DNA), biological cells, tissues and organs (lungs, kidneys and placenta), they all present irregularly shaped "scenes" for a fundamental transport "performance", that is, diffusion. Here, the geometrical complexity, entangled with the stochastic character of diffusive motion, results in numerous fascinating and sometimes unexpected effects like diffusion screening or localization. These effects control many diffusion-mediated processes that play an important role in heterogeneous catalysis, biochemical mechanisms, electrochemistry, growth phenomena, oil recovery, or building industry. In spite of a long and rich history of academic and industrial research in this field, it is striking to see how little we know about diffusion in complex geometries, especially the one whic...

Grebenkov, Denis

2009-01-01T23:59:59.000Z

144

Introduction The bay scallop, Argopecten irradi-  

E-Print Network [OSTI]

71(3) 17 Introduction The bay scallop, Argopecten irradi- ans amplicostatus, has been present (Garcia-Cubas, 1968). Historical Uses Mollusks were used by the pre-Co- lumbian cultures in Mexico as food

145

Selective irradiation of the vascular endothelium  

E-Print Network [OSTI]

We developed a unique methodology to selectively irradiate the vascular endothelium in vivo to better understand the role of vascular damage in causing normal tissue radiation side-effects.The relationship between vascular ...

Schuller, Bradley W

2007-01-01T23:59:59.000Z

146

Processing Irradiated Beryllium For Disposal  

SciTech Connect (OSTI)

The purpose of this research was to develop a process for decontaminating irradiated beryllium that will allow it to be disposed of through normal radwaste channels. Thus, the primary objectives of this ongoing study are to remove the transuranic (TRU) isotopes to less than 100 nCi/g and remove {sup 60}Co, and {sup 137}Cs, to levels that will allow the beryllium to be contact handled. One possible approach that appears to have the most promise is aqueous dissolution and separation of the isotopes by selected solvent extraction followed by precipitation, resulting in a granular form for the beryllium that may be fixed to prevent it from becoming respirable and therefore hazardous. Beryllium metal was dissolved in nitric and fluorboric acids. Isotopes of {sup 241}Am, {sup 239}Pu, {sup 85}Sr, and {sup 137}Cs were then added to make a surrogate beryllium waste solution. A series of batch contacts was performed with the spiked simulant using chlorinated cobalt dicarbollide (CCD) and polyethylene glycol diluted with sulfone to extract the isotopes of Cs and Sr. Another series of batch contacts was performed using a combination of octyl (phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) in tributyl phosphate (TBP) diluted with dodecane for extracting the isotopes of Pu and Am. The results indicate that greater than 99.9% removal can be achieved for each isotope with only three contact stages.

T. J. Tranter; R. D. Tillotson; N. R. Mann; G. R. Longhurst

2005-11-01T23:59:59.000Z

147

Neutron Irradiation Measurement for Superconducting Magnet  

E-Print Network [OSTI]

close to reactor core · Sample cool down by He gas loop: 10K ­ 20K · Fast neutron flux (En>0.1MeV): 1.4x. Materials, 49, p161 (1973&74) Reactor n on Al Reactor n on Cu fluence up to 2*1022 n/m2 (En>0.1MeV) RRR Irradiation at KUR · Kyoto Univ. Research Reactor Institute · MW max. thermal power · Irradiation cryostat

McDonald, Kirk

148

Optoelectronic switches based on diffusive conduction Hilmi Volkan Demira  

E-Print Network [OSTI]

Optoelectronic switches based on diffusive conduction Hilmi Volkan Demira and Fatih Hakan Koklu the process of diffusive conduction that we use in our optoelectronic switches to achieve rapid optical. We demonstrate the feasibility of using such diffusive conductive optoelectronic switches

Miller, David A. B.

149

Review of enhanced vapor diffusion in porous media  

SciTech Connect (OSTI)

Vapor diffusion in porous media in the presence of its own liquid has often been treated similar to gas diffusion. The gas diffusion rate in porous media is much lower than in free space due to the presence of the porous medium and any liquid present. However, enhanced vapor diffusion has also been postulated such that the diffusion rate may approach free-space values. Existing data and models for enhanced vapor diffusion, including those in TOUGH2, are reviewed in this paper.

Webb, S.W.; Ho, C.K.

1998-08-01T23:59:59.000Z

150

Mixing it up - Measuring diffusion in supercooled liquid solutions...  

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

Mixing it up - Measuring diffusion in supercooled liquid solutions of methanol and ethanol at temperatures near the glass Mixing it up - Measuring diffusion in supercooled liquid...

151

Non-Destructive Analysis Calibration Standards for Gaseous Diffusion...  

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

Non-Destructive Analysis Calibration Standards for Gaseous Diffusion Plant (GDP) Decommissioning Non-Destructive Analysis Calibration Standards for Gaseous Diffusion Plant (GDP)...

152

ar diffusion coefficient: Topics by E-print Network  

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

diffusion is examined. Kazuhiko Seki; Saurabh Mogre; Shigeyuki Komura 2014-02-05 4 Fractal diffusion coefficient from dynamical zeta functions Nonlinear Sciences (arXiv)...

153

axial diffusion coefficient: Topics by E-print Network  

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

diffusion is examined. Kazuhiko Seki; Saurabh Mogre; Shigeyuki Komura 2014-02-05 5 Fractal diffusion coefficient from dynamical zeta functions Nonlinear Sciences (arXiv)...

154

Oxygen Diffusion (OD) Dramatically Improves Wear-Resistance of...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Oxygen Diffusion (OD) Dramatically Improves Wear-Resistance of Titanium Oxygen Diffusion (OD) Dramatically Improves Wear-Resistance of Titanium 2007 Diesel Engine-Efficiency &...

155

Hydrogen diffusion in Lead Zirconate Titanate and Barium Titanate...  

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

diffusion in Lead Zirconate Titanate and Barium Titanate. Hydrogen diffusion in Lead Zirconate Titanate and Barium Titanate. Abstract: Hydrogen is a potential clean-burning,...

156

Formation of Hydrogen, Oxygen, and Hydrogen Peroxide in Electron Irradiated Crystalline Water Ice  

E-Print Network [OSTI]

Water ice is abundant both astrophysically, for example in molecular clouds, and in planetary systems. The Kuiper belt objects, many satellites of the outer solar system, the nuclei of comets and some planetary rings are all known to be water-rich. Processing of water ice by energetic particles and ultraviolet photons plays an important role in astrochemistry. To explore the detailed nature of this processing, we have conducted a systematic laboratory study of the irradiation of crystalline water ice in an ultrahigh vacuum setup by energetic electrons holding a linear energy transfer of 4.3 +/- 0.1 keV mm-1. The irradiated samples were monitored during the experiment both on line and in situ via mass spectrometry (gas phase) and Fourier transform infrared spectroscopy (solid state). We observed the production of hydrogen and oxygen, both molecular and atomic, and of hydrogen peroxide. The likely reaction mechanisms responsible for these species are discussed. Additional formation routes were derived from the sublimation profiles of molecular hydrogen (90-140 K), molecular oxygen (147 -151 K) and hydrogen peroxide (170 K). We also present evidence on the involvement of hydroxyl radicals and possibly oxygen atoms as building blocks to yield hydrogen peroxide at low temperatures (12 K) and via a diffusion-controlled mechanism in the warming up phase of the irradiated sample.

Weijun Zheng; David Jewitt; Ralf I. Kaiser

2005-11-18T23:59:59.000Z

157

Diffusion of Innovations over Multiplex Social Networks  

E-Print Network [OSTI]

The ways in which an innovation (e.g., new behaviour, idea, technology, product) diffuses among people can determine its success or failure. In this paper, we address the problem of diffusion of innovations over multiplex social networks where the neighbours of a person belong to one or multiple networks (or layers) such as friends, families, or colleagues. To this end, we generalise one of the basic game-theoretic diffusion models, called networked coordination game, for multiplex networks. We present analytical results for this extended model and validate them through a simulation study, finding among other properties a lower bound for the success of an innovation.While simple and leading to intuitively understandable results, to the best of our knowledge this is the first extension of a game-theoretic innovation diffusion model for multiplex networks and as such it provides a basic framework to study more sophisticated innovation dynamics.

Ramezanian, Rasoul; Magnani, Matteo; Montesi, Danilo

2014-01-01T23:59:59.000Z

158

Diffusion of innovations in social networks  

E-Print Network [OSTI]

While social networks do affect diffusion of innovations, the exact nature of these effects are far from clear, and, in many cases, there exist conflicting hypotheses among researchers. In this paper, we focus on the linear ...

Acemoglu, Daron

159

Princeton University Diffusion of Networking Technologies  

E-Print Network [OSTI]

Electronic Commerce (EC'12) Valencia, Spain June 7, 2012 ISP #12;Seedset: A set of nodes that can kick off, photovoltaics, fax, computers, Internet, video games, ... Source: Rogers. "The Diffusion of Home Computers Among

Goldberg, Sharon

160

Diffuser Augmented Wind Turbine Analysis Code  

E-Print Network [OSTI]

, it is necessary to develop innovative wind capturing devices that can produce energy in the locations where large conventional horizontal axis wind turbines (HAWTs) are too impractical to install and operate. A diffuser augmented wind turbine (DAWT) is one...

Carroll, Jonathan

2014-05-31T23:59:59.000Z

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


161

Electrospray emitters For diffusion vacuum pumps  

E-Print Network [OSTI]

Following similar principles as regular diffusion vacuum pumps, an electrospray emitter is set to produce a jet of charged particles that will drag air molecules out of a volume. To be a feasible concept, the emitted ...

Diaz Gómez Maqueo, Pablo (Pablo Ly)

2011-01-01T23:59:59.000Z

162

Diffusion Simulation and Lifetime Calculation at RHIC  

SciTech Connect (OSTI)

The beam lifetime is an important parameter for any storage ring. For protons in RHIC it is dominated by the non-linear nature of the head-on collisions that causes the particles to diffuse outside the stable area in phase space. In this report we show results from diffusion simulation and lifetime calculation for the 2006 and 2008 polarized proton runs in RHIC.

Abreu,N.P.; Fischer, W.; Luo, Y.; Robert-Demolaize, G.

2009-01-02T23:59:59.000Z

163

Diffusion Preconditioner for Discontinuous Galerkin Transport Problems  

E-Print Network [OSTI]

DIFFUSION PRECONDITIONER FOR DISCONTINUOUS GALERKIN TRANSPORT PROBLEMS A Thesis by ANTHONY PETRU BARBU Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree of MASTER... OF SCIENCE May 2011 Major Subject: Nuclear Engineering DIFFUSION PRECONDITIONER FOR DISCONTINUOUS GALERKIN TRANSPORT PROBLEMS A Thesis by ANTHONY PETRU BARBU Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment...

Barbu, Anthony Petru

2011-08-08T23:59:59.000Z

164

E-Print Network 3.0 - additive irradiation procedures Sample...  

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

irradiation procedures Search Powered by Explorit Topic List Advanced Search Sample search results for: additive irradiation procedures Page: << < 1 2 3 4 5 > >> 1 IRRADIANCE MAPS...

165

Diffusion of Small He Clusters in Bulk and Grain Boundaries in ?-Fe  

SciTech Connect (OSTI)

The diffusion properties of He interstitials and He clusters in the bulk and grain boundaries (GBs) of ?-Fe have been studied using molecular dynamics with a newly developed Fe?He potential. The low migration energy barrier for a single He interstitial in the bulk is consistent with that obtained using ab initio methods. Small He clusters can migrate at low temperatures, but at higher temperatures they will kick out a self-interstitial atom (SIA) and become trapped by the vacancy, forming an He-vacancy complex. It is of great interest to note that small Henvacancy clusters (n<5) in the bulk are able to absorb an SIA, and the clusters become mobile again. Trapping and de-trapping of He clusters by emitting and absorbing an SIA represent an important dynamic process that provides a mechanism for the diffusion of He clusters and the nucleation of He bubbles in bulk Fe, particularly under irradiation in which numerous SIAs and vacancies are constantly being produced. A single He interstitial can migrate one-dimensionally or two-dimensionally within GBs, depending on the GB structure. Small interstitial Hen clusters 2 (n ~ 1 - 10) can easily kick out an SIA, and become trapped by the vacancy, while the SIA quickly diffuses away from the clusters, disappearing into the GB, such that de-trapping of the He clusters by absorbing an SIA is less likely to occur. This suggests that small He clusters may be treated as relatively immobile defects in GBs. The different behavior of He clusters in the bulk compared to their behavior in GBs may explain the different He bubble sizes experimentally observed in the bulk and in GBs in reduced activation ferritic/martensitic steels that have been simultaneously neutron irradiated and He implanted.

Deng, Huiqiu; Hu, W. Y.; Gao, Fei; Heinisch, Howard L.; Hu, Shenyang Y.; Li, Yulan; Kurtz, Richard J.

2013-11-02T23:59:59.000Z

166

Horizontal modular dry irradiated fuel storage system  

DOE Patents [OSTI]

A horizontal, modular, dry, irradiated fuel storage system (10) includes a thin-walled canister (12) for containing irradiated fuel assemblies (20), which canister (12) can be positioned in a transfer cask (14) and transported in a horizontal manner from a fuel storage pool (18), to an intermediate-term storage facility. The storage system (10) includes a plurality of dry storage modules (26) which accept the canister (12) from the transfer cask (14) and provide for appropriate shielding about the canister (12). Each module (26) also provides for air cooling of the canister (12) to remove the decay heat of the irradiated fuel assemblies (20). The modules (26) can be interlocked so that each module (26) gains additional shielding from the next adjacent module (26). Hydraulic rams (30) are provided for inserting and removing the canisters (12) from the modules (26).

Fischer, Larry E. (Los Gatos, CA); McInnes, Ian D. (San Jose, CA); Massey, John V. (San Jose, CA)

1988-01-01T23:59:59.000Z

167

Laboratory for Characterization of Irradiated Graphite  

SciTech Connect (OSTI)

The newly completed Idaho National Laboratory (INL) Carbon Characterization Laboratory (CCL) is located in Labs C19 and C20 of the Idaho National Laboratory Research Center (IRC). The CCL was established under the Next Generation Nuclear Plant (NGNP) Project to support graphite and ceramic composite research and development activities. The research is in support of the Advanced Graphite Creep (AGC) experiment — a major material irradiation experiment within the NGNP Graphite program. The CCL is designed to characterize and test low activated irradiated materials such as high purity graphite, carbon-carbon composites, and silicon-carbide composite materials. The laboratory is fully capable of characterizing material properties for both irradiated and nonirradiated materials.

Karen A. Moore

2010-03-01T23:59:59.000Z

168

Irradiation creep of vanadium-base alloys.  

SciTech Connect (OSTI)

A study of irradiation creep in vanadium-base alloys is underway with experiments in the Advanced Test Reactor (ATR) and the High Flux Isotope Reactor (HFIR) in the US. Test specimens are thin-wall sealed tubes with internal pressure loading. The results from the initial ATR irradiation at low temperature (200-300 C) to a neutron damage level of 4.7 dpa show creep rates ranging from {approx}0 to 1.2 x 10{sup {minus}5}/dpa/MPa for a 500-kg heat of V-4Cr-4Ti alloy. These rates were generally lower than reported from a previous experiment in BR-10. Because both the attained neutron damage levels and the creep strains were low in the present study, however, these creep rates should be regarded as only preliminary. Substantially more testing is required before a data base on irradiation creep of vanadium alloys can be developed and used with confidence.

Tsai, H.; Matsui, H.; Billone, M. C.; Strain, R. V.; Smith, D. L.

1998-05-18T23:59:59.000Z

169

Irradiation effects on borosilicate waste glasses  

SciTech Connect (OSTI)

The effects of alpha decay on five borosilicate glasses containing simulated nuclear high-level waste oxides were studied. Irradiations carried out at room temperature were achieved by incorporating 1 to 8 wt % /sup 244/Cm/sub 2/O/sub 3/ in the glasses. Density changes and stored-energy build-up saturated at doses less than 2 x 10/sup 21/ alpha decays/kg. Damage manifested by stored energy was completely annealed at 633/sup 0/K. Positive and negative density changes were observed which never exceeded 1%. Irradiation had very little effect on mechanical strength or on chemical durability as measured by aqueous leach rates. Also, no effects were observed on the microstructure for vitreous waste glasses, although radiation-induced microcracking could be achieved on specimens that had been devitrified prior to irradiation.

Roberts, F.P.

1980-06-01T23:59:59.000Z

170

Heavy ion irradiation of crystalline water ice  

E-Print Network [OSTI]

Under cosmic irradiation, the interstellar water ice mantles evolve towards a compact amorphous state. Crystalline ice amorphisation was previously monitored mainly in the keV to hundreds of keV ion energies. We experimentally investigate heavy ion irradiation amorphisation of crystalline ice, at high energies closer to true cosmic rays, and explore the water-ice sputtering yield. We irradiated thin crystalline ice films with MeV to GeV swift ion beams, produced at the GANIL accelerator. The ice infrared spectral evolution as a function of fluence is monitored with in-situ infrared spectroscopy (induced amorphisation of the initial crystalline state into a compact amorphous phase). The crystalline ice amorphisation cross-section is measured in the high electronic stopping-power range for different temperatures. At large fluence, the ice sputtering is measured on the infrared spectra, and the fitted sputtering-yield dependence, combined with previous measurements, is quadratic over three decades of electronic ...

Dartois, E; Boduch, P; Brunetto, R; Chabot, M; Domaracka, A; Ding, J J; Kamalou, O; Lv, X Y; Rothard, H; da Silveira, E F; Thomas, J C

2015-01-01T23:59:59.000Z

171

Heavy-Section Steel Irradiation Program  

SciTech Connect (OSTI)

Maintaining the integrity of the reactor pressure vessel (RPV) in a light-water-cooled nuclear power plant is crucial in preventing and controlling severe accidents that have the potential for major contamination release. Because the RPV is the only key safety-related component of the plant for which a redundant backup system does not exist, it is imperative to fully understand the degree of irradiation-induced degradation of the RPV's fracture resistance that occurs during service. For this reason, the Heavy-Section Steel Irradiation (HSSI) Program has been established.

Rosseel, T.M.

2000-04-01T23:59:59.000Z

172

Gamma irradiation of the prenatal mouse dentition  

E-Print Network [OSTI]

as the dental lamina to the stage of the deposition of enamel and dentin. The purpose of this study was to determine the effect of a continuous stress of gamma irradiation on the structure of the odontogenic cells, the relative size and rate of development... development. In 1927, Leist (9) made a study of the effect of X-rays on teeth, which was brought about by the following rase. A worker in a Roentgen tube factory was exposed daily to a considerable dose of X-irradiation. Sometime later he began to show...

Kerley, Michael Auston

1969-01-01T23:59:59.000Z

173

Effects of neutron flux and irradiation temperature on irradiation embrittlement of A533B steels  

SciTech Connect (OSTI)

Irradiation embrittlement of A533B steels with low copper contents were investigated from the point of dose rate and irradiation temperature effects. Change of neutron flux in the range from {minus}10{sup 12} to {minus}10{sup 13} n/cm{sup 2}/s (E > 1 MeV) did not have a significant effect on the embrittlement. Irradiation temperature change of 1 C resulted in the transition temperature shift ({Delta}T{sub 41J}) of about 1 C and yield stress change ({Delta}{sigma}{sub y}) of about 0.8 MPa. Factors that might affect the embrittlement of low copper steels are also discussed.

Suzuki, Masahide; Onizawa, Kunio; Kizaki, Minoru [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)

1996-12-31T23:59:59.000Z

174

Fructolysis in the semen of continuously irradiated and non-irradiated goats  

E-Print Network [OSTI]

Abbott showed that the androgenic activity of the testis is far more resistant to x- ray irradiation than is the germinal epi- 1 thelium. When Abbott administered 5, 000 and 10, OOOR to rats, he found no decrease in the sex accessory organ weights nor.... Another point which supports the data that the damaged spermatogonia give rise to subnormal sperm is 23 the studies done with in vitro sperm that have been irradiated. Man 15 stated that irradiation of whole, fresh semen has little or no effect...

Ziller, Henry Hubert

1966-01-01T23:59:59.000Z

175

Eddy diffusivities of inertial particles under gravity  

E-Print Network [OSTI]

The large-scale/long-time transport of inertial particles of arbitrary mass density under gravity is investigated by means of a formal multiple-scale perturbative expansion in the scale-separation parametre between the carrier flow and the particle concentration field. The resulting large-scale equation for the particle concentration is determined, and is found to be diffusive with a positive-definite eddy diffusivity. The calculation of the latter tensor is reduced to the resolution of an auxiliary differential problem, consisting of a coupled set of two differential equations in a (6+1)-dimensional coordinate system (3 space coordinates plus 3 velocity coordinates plus time). Although expensive, numerical methods can be exploited to obtain the eddy diffusivity, for any desirable non-perturbative limit (e.g. arbitrary Stokes and Froude numbers). The aforementioned large-scale equation is then specialized to deal with two different relevant perturbative limits: i) vanishing of both Stokes time and sedimenting particle velocity; ii) vanishing Stokes time and finite sedimenting particle velocity. Both asymptotics lead to a greatly simplified auxiliary differential problem, now involving only space coordinates and thus easy to be tackled by standard numerical techniques. Explicit, exact expressions for the eddy diffusivities have been calculated, for both asymptotics, for the class of parallel flows, both static and time-dependent. This allows us to investigate analytically the role of gravity and inertia on the diffusion process by varying relevant features of the carrier flow, as e.g. the form of its temporal correlation function. Our results exclude a universal role played by gravity and inertia on the diffusive behaviour: regimes of both enhanced and reduced diffusion may exist, depending on the detailed structure of the carrier flow.

Marco Martins Afonso; Andrea Mazzino; Paolo Muratore-Ginanneschi

2011-03-29T23:59:59.000Z

176

Understanding the Irradiation Behavior of Zirconium Carbide  

SciTech Connect (OSTI)

Zirconium carbide (ZrC) is being considered for utilization in high-temperature gas-cooled reactor fuels in deep-burn TRISO fuel. Zirconium carbide possesses a cubic B1-type crystal structure with a high melting point, exceptional hardness, and good thermal and electrical conductivities. The use of ZrC as part of the TRISO fuel requires a thorough understanding of its irradiation response. However, the radiation effects on ZrC are still poorly understood. The majority of the existing research is focused on the radiation damage phenomena at higher temperatures (>450{degree}C) where many fundamental aspects of defect production and kinetics cannot be easily distinguished. Little is known about basic defect formation, clustering, and evolution of ZrC under irradiation, although some atomistic simulation and phenomenological studies have been performed. Such detailed information is needed to construct a model describing the microstructural evolution in fast-neutron irradiated materials that will be of great technological importance for the development of ZrC- based fuel. The goal of the proposed project is to gain fundamental understanding of the radiation-induced defect formation in zirconium carbide and irradiation response (ZrC) by using a combination of state-of-the-art experimental methods and atomistic modeling. This project will combine (1) in situ ion irradiation at a specialized facility at a national laboratory, (2) controlled temperature proton irradiation on bulk samples, and (3) atomistic modeling to gain a fundamental understanding of defect formation in ZrC. The proposed project will cover the irradiation temperatures from cryogenic temperature to as high as 800{degree}C, and dose ranges from 0.1 to 100 dpa. The examination of this wide range of temperatures and doses allows us to obtain an experimental data set that can be effectively used to exercise and benchmark the computer calculations of defect properties. Combining the examination of radiation-induced microstructures mapped spatially and temporally, microstructural evolution during post-irradiation annealing, and atomistic modeling of defect formation and transport energetics will provide new, critical understanding about property changes in ZrC. The behavior of materials under irradiation is determined by the balance between damage production, defect clustering, and lattice response. In order to predict those effects at high temperatures so targeted testing can be expanded and extrapolated beyond the known database, it is necessary to determine the defect energetics and mobilities as these control damage accumulation and annealing. In particular, low-temperature irradiations are invaluable for determining the regions of defect mobility. Computer simulation techniques are particularly useful for identifying basic defect properties, especially if closely coupled with a well-constructed and complete experimental database. The close coupling of calculation and experiment in this project will provide mutual benchmarking and allow us to glean a deeper understanding of the irradiation response of ZrC, which can then be applied to the prediction of its behavior in reactor conditions.

Motta, Arthur; Sridharan, Kumar; Morgan, Dane; Szlufarska, Izabela

2013-10-11T23:59:59.000Z

177

Improving ion irradiated high T{sub c} Josephson junctions by annealing: The role of vacancy-interstitial annihilation  

SciTech Connect (OSTI)

The authors have studied the annealing effect in the transport properties of high T{sub c} Josephson junctions (JJs) made by ion irradiation. Low temperature annealing (80 deg. C) increases the JJ coupling temperature (T{sub J}) and the I{sub c}R{sub n} product, where I{sub c} is the critical current and R{sub n} the normal resistance. They have found that the spread in JJ characteristics can be reduced by sufficient long annealing times, increasing the reproducibility of ion irradiated Josephson junctions. The characteristic annealing time and the evolution of the spread in the JJ characteristics can be explained by a vacancy-interstitial annihilation process rather than by an oxygen diffusion one.

Sirena, M.; Matzen, S.; Bergeal, N.; Lesueur, J.; Faini, G.; Bernard, R.; Briatico, J.; Crete, D. G. [Laboratoire Photons Et Matiere, ESPCI, 10 Rue Vauquelin, 75231 Paris (France); Laboratoire de Photonique et Nanostructures, Route de Nozay, 91460 Marcoussis (France); UMR-CNRS/THALES, Route D128, 91767 Palaiseau (France)

2007-10-01T23:59:59.000Z

178

Response of Strontium Titanate to Ion and Electron Irradiation...  

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

Strontium Titanate to Ion and Electron Irradiation. Response of Strontium Titanate to Ion and Electron Irradiation. Abstract: Response of strontium titanate (SrTiO3) to ion and...

179

Irradiation Stability of Carbon Nanotubes and Related Materials  

E-Print Network [OSTI]

defect annealing at elevated irradiation temperatures, which delays the formation of amorphous regions. Investigation of nanotube stability after various processing techniques and irradiation indicated that radiation response of CNTs in a composite...

Aitkaliyeva, Assel 1985-

2012-09-28T23:59:59.000Z

180

E-Print Network 3.0 - accelerated hyperfractionated irradiation...  

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

Group Collection: Physics 79 Irradiation of Nd-Fe-B Permanent Magnets with APS Bending Magnet X-rays and 60 Summary: of 260 Mrad was used to irradiate Nd-Fe-B sample magnets with...

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


181

diffusion-fundamentals The Open-Access Journal for the Basic Principles of Diffusion Theory, Experiment and Application  

E-Print Network [OSTI]

× 10­10 H+ -Diffusion, symmetr. H-bond (TD) ~0.3 4 × 10­09 The method allowing us to isolate specificdiffusion-fundamentals The Open-Access Journal for the Basic Principles of Diffusion Theory, Experiment and Application www.diffusion-fundamentals.org, ISSN 1862-4138; © 2005-2010 Diffusion Fundamentals

Schuck, Götz

182

Implementation Plan for the Irradiated Materials Characterization Laboratory (IMCL)  

SciTech Connect (OSTI)

This document contains details regarding the planned implementation of the Irradiated Materials Characterization Laboratory at the INL.

Not Listed

2013-04-01T23:59:59.000Z

183

Effects of hadron irradiation on scintillating fibers  

SciTech Connect (OSTI)

Trackers based on scintillating-fiber technology are being considered by the Solenoidal Detector Collaboration at SSC and the D[phi] collaboration at Fermilab. An important issue is the effect of the radiation existing in the detector cores on fiber properties. Most studies of radiation damage in scintillators have irradiated small bulk samples rather than fibers, and have used X-rays, [sup 60]Co gammas, or electron beams, often at accelerated rates. The authors have irradiated some 600 fibers in the Fermilab Tevatron C[phi] area, thereby obtaining a hadronic irradiation at realistic rates. Four-meter-long samples of ten Bicron polystyrene-based fiber types, maintained in air, dry nitrogen, argon, and vacuum atmospheres within stainless-steel tubes, were irradiated for seven weeks at various distances from the accelerator beam pipes. Maximum doses, measured by thermoluminescence detectors, were about 80 Krad. Fiber properties, particularly light yield and attenuation length, have been measured over a one-year period. A description of the work together with the results is presented. At the doses achieved, corresponding to a few years of actual fiber-tracking detector operation, little degradation is observed. In addition, recovery after several days' exposure to air has been noted. Properties of unirradiated samples kept in darkness show no changes after one year.

Atac, M. (Univ. of California, Los Angeles, CA (United States) Fermi National Accelerator Lab., Batavia, IL (United States)); Buchanan, C.; Chrisman, D.; Cline, D.; Kolonko, J.; Kubic, J.; Park, J. (Univ. of California, Los Angeles, CA (United States)); Baumbaugh, A.; Binkley, M.; Bross, A.D.; Finley, D.; Elias, J.; Foster, G.W.; Kephart, R.; Kephart, R.; Kim, C.; Park, H.; Pla-Dalmau, A.; Rivetta, C.; Tkaczyk, S.; Wagner, R. (Fermi National Accelerator Lab., Batavia, IL (United States)); Chung, M.; Goldberg, H.; Jeskik, R.; Margulies, S.; Mendez, H.; Solomon, J.; Vaca, F. (Univ. of Illinois, Chicago, IL (United States)); Kelley, C. (Massachusetts College of Pharmacy and Allied Health Sciences, Boston, MA (United States)); Baumbaugh, B.; Bishop, J.; Biswas, N.; Cason, N.; Jacques, J.; Kehoe, R.; Kelly, M.; Kenney, V.; LoSecco, J.; Ruchti, R.; Shephard, W.; Warchol, J.; Wayne, M.; Marchant, J.; Mountain, R.J. (Univ. of Notre Dame, IN (United States)); Davis, D.; Vandergriff, D. (O

1993-08-01T23:59:59.000Z

184

SIPS: Solar Irradiance Prediction System Stefan Achleitner  

E-Print Network [OSTI]

-scaling capacities of renewable energy sources such as wind and solar. However, variability and uncertainty in powerSIPS: Solar Irradiance Prediction System Stefan Achleitner Computer Science and Engineering Liu and Alberto E. Cerpa Electrical Engineering and Computer Science University of California, Merced

Cerpa, Alberto E.

185

Continuous wave laser irradiation of explosives  

SciTech Connect (OSTI)

Quantitative measurements of the levels of continuous wave (CW) laser light that can be safely applied to bare explosives during contact operations were obtained at 532 nm, 785 nm, and 1550 nm wavelengths. A thermal camera was used to record the temperature of explosive pressed pellets and single crystals while they were irradiated using a measured laser power and laser spot size. A visible light image of the sample surface was obtained before and after the laser irradiation. Laser irradiation thresholds were obtained for the onset of any visible change to the explosive sample and for the onset of any visible chemical reaction. Deflagration to detonation transitions were not observed using any of these CW laser wavelengths on single crystals or pressed pellets in the unconfined geometry tested. Except for the photochemistry of DAAF, TATB and PBX 9502, all reactions appeared to be thermal using a 532 nm wavelength laser. For a 1550 nm wavelength laser, no photochemistry was evident, but the laser power thresholds for thermal damage in some of the materials were significantly lower than for the 532 nm laser wavelength. No reactions were observed in any of the studied explosives using the available 300 mW laser at 785 nm wavelength. Tables of laser irradiance damage and reaction thresholds are presented for pressed pellets of PBX9501, PBX9502, Composition B, HMX, TATB, RDX, DAAF, PETN, and TNT and single crystals of RDX, HMX, and PETN for each of the laser wavelengths.

McGrane, Shawn D.; Moore, David S.

2010-12-01T23:59:59.000Z

186

The Sun and Climate Solar Irradiance  

E-Print Network [OSTI]

The Sun and Climate #12;Solar Irradiance The Solar Constant f = 1.4 x 106 erg/cm2/s. Over is higher when the Sun is more magnetically active. ·The Sun was magnetically active, and the climate the Sun Drive Climate? #12;The Temperature's Rising #12;Sunspots and CO2 What is Cause and What is Effect

Walter, Frederick M.

187

Total Solar Irradiance Satellite Composites and their  

E-Print Network [OSTI]

Chapter 12 Total Solar Irradiance Satellite Composites and their Phenomenological Effect on Climate. Phenomenological solar signature on climate 310 9. Conclusion 312 1. INTRODUCTION A contiguoustotal solar from each other, in particular about whether the TSI minimum during solar Cycles 22e23 (1995

Scafetta, Nicola

188

Irradiation Embritlement in Alloy HT-­9  

SciTech Connect (OSTI)

HT-9 steel is a candidate structural and cladding material for high temperature lead-bismuth cooled fast reactors. In typical advanced fast reactor designs fuel elements will be irradiated for an extended period of time, reaching up to 5-7 years. Significant displacement damage accumulation in the steel is expected (> 200 dpa) when exposed to dpa-rates of 20-30 dpa{sub Fe}/y and high fast flux (E > 0.1 MeV) {approx}4 x 10{sup 15} n/cm{sup 2}s. Core temperatures could reach 400-560 C, with coolant temperatures at the inlet as low as 250 C, depending on the reactor design. Mechanical behavior in the presence of an intense fast flux and high dose is a concern. In particular, low temperature operation could be limited by irradiation embrittlement. Creep and corrosion effects in liquid metal coolants could set a limit to the upper operating temperature. In this report, we focus on the low temperature operating window limit and describe HT-9 embrittlement experimental findings reported in the literature that could provide supporting information to facilitate the consideration of a Code Case on irradiation effects for this class of steels in fast reactor environments. HT-9 has an extensive database available on irradiation performance, which makes it the best choice as a possible near-term candidate for clad, and ducts in future fast reactors. Still, as it is shown in this report, embrittlement data for very low irradiation temperatures (< 200 C) and very high radiation exposure (> 150 dpa) is scarce. Experimental findings indicate a saturation of DBTT shifts as a function of dose, which could allow for long lifetime cladding operation. However, a strong increase in DBTT shift with decreasing irradiation temperature could compromise operation at low service temperatures. Development of a deep understanding of the physics involved in the radiation damage mechanisms, together with multiscale computer simulation models of irradiation embrittlement will provide the basis to derive trendlines and quantitative engineering predictions.

Serrano De Caro, Magdalena [Los Alamos National Laboratory

2012-08-27T23:59:59.000Z

189

Response of neutron-irradiated RPV steels to thermal annealing  

SciTech Connect (OSTI)

One of the options to mitigate the effects of irradiation on reactor pressure vessels (RPVs) is to thermally anneal them to restore the fracture toughness properties that have been degraded by neutron irradiation. This paper summarizes experimental results of work performed at the Oak Ridge National Laboratory (ORNL) to study the annealing response of several irradiated RPV steels.

Iskander, S.K.; Sokolov, M.A.; Nanstad, R.K.

1997-03-01T23:59:59.000Z

190

Total solar irradiance during the Holocene F. Steinhilber,1  

E-Print Network [OSTI]

Total solar irradiance during the Holocene F. Steinhilber,1 J. Beer,1 and C. Fro¨hlich2 Received 20 solar irradiance covering 9300 years is presented, which covers almost the entire Holocene. This reconstruction is based on a recently observationally derived relationship between total solar irradiance

Wehrli, Bernhard

191

The Diffuse Nature of Stromgren Spheres  

E-Print Network [OSTI]

In this Letter, we argue that the standard analytical derivations of properties of HII regions, such as the speed, shape and asymptotic position of ionisation fronts require a more precise treatment. These derivations use the on the spot approximation, which in effect ignores the diffuse component of the radiation field. We show that, in fact, HII regions are diffusion dominated. This has as a result that the morphology of inhomogeneous HII regions will be drastically different, because shadowing effects have a less profound impact on the apparent shape. Moreover, it will have influence on the propagation speed of ionisation fronts. We quantify our claims by analytically deriving the internal radiation structure of HII regions, taking diffusion fully into account for several different cosmologically relevant density distributions.

J. Ritzerveld

2005-06-27T23:59:59.000Z

192

Anomalous diffusion modifies solar neutrino fluxes  

E-Print Network [OSTI]

Density and temperature conditions in the solar core suggest that the microscopic diffusion of electrons and ions could be nonstandard: diffusion and friction coefficients are energy dependent, collisions are not two-body processes and retain memory beyond the single scattering event. A direct consequence of nonstandard diffusion is that the equilibrium energy distribution of particles departs from the Maxwellian one (tails goes to zero more slowly or faster than exponentially) modifying the reaction rates. This effect is qualitatively different from temperature and/or composition modification: small changes in the number of particles in the distribution tails can strongly modify the rates without affecting bulk properties, such as the sound speed or hydrostatic equilibrium, which depend on the mean values from the distribution. This mechanism can considerably increase the range of predictions for the neutrino fluxes allowed by the current experimental values (cross sections and solar properties) and can be u...

Kaniadakis, G; Lissia, M; Quarati, P

1998-01-01T23:59:59.000Z

193

Robust diffusion imaging framework for clinical studies  

E-Print Network [OSTI]

Clinical diffusion imaging requires short acquisition times and good image quality to permit its use in various medical applications. In turn, these demands require the development of a robust and efficient post-processing framework in order to guarantee useful and reliable results. However, multiple artefacts abound in in vivo measurements; from either subject such as cardiac pulsation, bulk head motion, respiratory motion and involuntary tics and tremor, or imaging hardware related problems, such as table vibrations, etc. These artefacts can severely degrade the resulting images and render diffusion analysis difficult or impossible. In order to overcome these problems, we developed a robust and efficient framework enabling the use of initially corrupted images from a clinical study. At the heart of this framework is an improved least trimmed squares diffusion tensor estimation algorithm that works well with severely degraded datasets with low signal-to-noise ratio. This approach has been compared with other...

Maximov, Ivan I; Neuner, Irene; Shah, N Jon

2015-01-01T23:59:59.000Z

194

Sensitivity of ultrasonic nonlinearity to irradiated, annealed, and re-irradiated microstructure changes in RPV steels  

SciTech Connect (OSTI)

The planned life extension of nuclear reactors throughout the US and abroad will cause reactor vessel and internals materials to be exposed to more neutron irradiation than was originally intended. A nondestructive evaluation (NDE) method to monitor radiation damage would enable safe and cost-effective continued operation of nuclear reactors. Radiation damage in reactor pressure vessel (RPV) steels causes microstructural changes that leave the material in an embrittled state. Nonlinear ultrasound is an NDE technique quantified by the measurable acoustic nonlinearity parameter, which is sensitive to microstructural changes in metallic materials such as dislocations, precipitates and their combinations. Recent research has demonstrated the sensitivity of the acoustic nonlinearity parameter to increasing neutron fluence in representative RPV steels. The current work considers nonlinear ultrasonic experiments conducted on similar RPV steel samples that had a combination of irradiation, annealing, re-irradiation, and/or re-annealing to a total neutron fluence of 0.5 5 1019 n/cm2 (E > 1 MeV) at an irradiation temperature of 290 C. The acoustic nonlinearity parameter generally increased with increasing neutron fluence, and consistently decreased from the irradiated to the annealed state over different levels of neutron fluence. Results of the measured acoustic nonlinearity parameter are compared with those from previous measurements on other RPV steel samples. This comprehensive set of results illustrates the dependence of the measured acoustic nonlinearity parameter on neutron fluence, material composition, irradiation temperature and annealing.

Matlack, Katie [Georgia Institute of Technology, Atlanta] [Georgia Institute of Technology, Atlanta; Kim, J-Y. [Georgia Institute of Technology, Atlanta] [Georgia Institute of Technology, Atlanta; Wall, J.J. [Electric Power Research Institute (EPRI)] [Electric Power Research Institute (EPRI); Jacobs, L.J. [Georgia Institute of Technology, Atlanta] [Georgia Institute of Technology, Atlanta; Sokolov, Mikhail A [ORNL] [ORNL

2014-01-01T23:59:59.000Z

195

Development of Diffusion barrier coatings and Deposition Technologies for Mitigating Fuel Cladding Chemical Interactions (FCCI)  

SciTech Connect (OSTI)

The goal of this project is to develop diffusion barrier coatings on the inner cladding surface to mitigate fuel-cladding chemical interaction (FCCI). FCCI occurs due to thermal and radiation enhanced inter-diffusion between the cladding and fuel materials, and can have the detrimental effects of reducing the effective cladding wall thickness and lowering the melting points of the fuel and cladding. The research is aimed at the Advanced Burner Reactor (ABR), a sodium-cooled fast reactor, in which higher burn-ups will exacerbate the FCCI problem. This project will study both diffusion barrier coating materials and deposition technologies. Researchers will investigate pure vanadium, zirconium, and titanium metals, along with their respective oxides, on substrates of HT-9, T91, and oxide dispersion-strengthened (ODS) steels; these materials are leading candidates for ABR fuel cladding. To test the efficacy of the coating materials, the research team will perform high-temperature diffusion couple studies using both a prototypic metallic uranium fuel and a surrogate�¢����the rare-earth element lanthanum. Ion irradiation experiments will test the stability of the coating and the coating-cladding interface. A critical technological challenge is the ability to deposit uniform coatings on the inner surface of cladding. The team will develop a promising non-line-of-sight approach that uses nanofluids . Recent research has shown the feasibility of this simple yet novel approach to deposit coatings on test flats and inside small sections of claddings. Two approaches will be investigated: 1) modified electrophoretic deposition (MEPD) and 2) boiling nanofluids. The coatings will be evaluated in the as-deposited condition and after sintering.

Sridharan, Kumar; Allen, Todd; Cole, James

2013-02-27T23:59:59.000Z

196

Effect of Diffusion on Bunched Beam Echo  

SciTech Connect (OSTI)

When a beam receives a dipole kick, its centroid signal decoheres due to the betatron tune spread in the beam. Long after the signal has decohered, however, a followup quadrupole kick to the beam brings a pronounced echo back to the centroid signal. This echo effect has been analyzed for the case of a bunched beam in Ref. [1]. In this work, the perturbation calculation of Ref. [1] is extended to include a diffusion in betatron amplitude. The effect of diffusion on the magnitude of the echo is then parameterized and studied.

Stupakov, G.V.; Chao, A.W.; /SLAC

2011-09-01T23:59:59.000Z

197

Self- and zinc diffusion in gallium antimonide  

SciTech Connect (OSTI)

The technological age has in large part been driven by the applications of semiconductors, and most notably by silicon. Our lives have been thoroughly changed by devices using the broad range of semiconductor technology developed over the past forty years. Much of the technological development has its foundation in research carried out on the different semiconductors whose properties can be exploited to make transistors, lasers, and many other devices. While the technological focus has largely been on silicon, many other semiconductor systems have applications in industry and offer formidable academic challenges. Diffusion studies belong to the most basic studies in semiconductors, important from both an application as well as research standpoint. Diffusion processes govern the junctions formed for device applications. As the device dimensions are decreased and the dopant concentrations increased, keeping pace with Moore's Law, a deeper understanding of diffusion is necessary to establish and maintain the sharp dopant profiles engineered for optimal device performance. From an academic viewpoint, diffusion in semiconductors allows for the study of point defects. Very few techniques exist which allow for the extraction of as much information of their properties. This study focuses on diffusion in the semiconductor gallium antimonide (GaSb). As will become clear, this compound semiconductor proves to be a powerful one for investigating both self- and foreign atom diffusion. While the results have direct applications for work on GaSb devices, the results should also be taken in the broader context of III-V semiconductors. Results here can be compared and contrasted to results in systems such as GaAs and even GaN, indicating trends within this common group of semiconductors. The results also have direct importance for ternary and quaternary semiconductor systems used in devices such as high speed InP/GaAsSb/InP double heterojunction bipolar transistors (DHBT) [Dvorak, (2001)]. Many of the findings which will be reported here were previously published in three journal articles. Hartmut Bracht was the lead author on two articles on self-diffusion studies in GaSb [Bracht, (2001), (2000)], while this report's author was the lead author on Zn diffusion results [Nicols, (2001)]. Much of the information contained herein can be found in those articles, but a more detailed treatment is presented here.

Nicols, Samuel Piers

2002-03-26T23:59:59.000Z

198

Fractal diffusion coefficient from dynamical zeta functions  

E-Print Network [OSTI]

Dynamical zeta functions provide a powerful method to analyze low dimensional dynamical systems when the underlying symbolic dynamics is under control. On the other hand even simple one dimensional maps can show an intricate structure of the grammar rules that may lead to a non smooth dependence of global observable on parameters changes. A paradigmatic example is the fractal diffusion coefficient arising in a simple piecewise linear one dimensional map of the real line. Using the Baladi-Ruelle generalization of the Milnor-Thurnston kneading determinant we provide the exact dynamical zeta function for such a map and compute the diffusion coefficient from its smallest zero.

G. Cristadoro

2005-09-28T23:59:59.000Z

199

Effects of stress on microstructural evolution during irradiation  

SciTech Connect (OSTI)

Many theories have been postulated to describe irradiation creep but few have been supported with microstructural evidence. The purpose of this paper is to review microstructural studies of the effects of stress during irradiation in order to assess the validity of the available irradiation creep theories. Microstructural studies based on high voltage electron, ion, proton and neutron irradiation will be described, with major emphasis placed on interpreting behavior demonstrated in austenitic steels. Special attention will be given to work on fast neutron irradiated Nimonic PE16, a precipitation strengthened superalloy.

Gelles, D.S. [Pacific Northwest Lab., Richland, VA (United States)

1992-12-31T23:59:59.000Z

200

Developing A Laser Shockwave Model For Characterizing Diffusion Bonded Interfaces  

SciTech Connect (OSTI)

12. Other advances in QNDE and related topics: Preferred Session Laser-ultrasonics Developing A Laser Shockwave Model For Characterizing Diffusion Bonded Interfaces 41st Annual Review of Progress in Quantitative Nondestructive Evaluation Conference QNDE Conference July 20-25, 2014 Boise Centre 850 West Front Street Boise, Idaho 83702 James A. Smith, Jeffrey M. Lacy, Barry H. Rabin, Idaho National Laboratory, Idaho Falls, ID ABSTRACT: The US National Nuclear Security Agency has a Global Threat Reduction Initiative (GTRI) which is assigned with reducing the worldwide use of high-enriched uranium (HEU). A salient component of that initiative is the conversion of research reactors from HEU to low enriched uranium (LEU) fuels. An innovative fuel is being developed to replace HEU. The new LEU fuel is based on a monolithic fuel made from a U-Mo alloy foil encapsulated in Al-6061 cladding. In order to complete the fuel qualification process, the laser shock technique is being developed to characterize the clad-clad and fuel-clad interface strengths in fresh and irradiated fuel plates. The Laser Shockwave Technique (LST) is being investigated to characterize interface strength in fuel plates. LST is a non-contact method that uses lasers for the generation and detection of large amplitude acoustic waves to characterize interfaces in nuclear fuel plates. However the deposition of laser energy into the containment layer on specimen’s surface is intractably complex. The shock wave energy is inferred from the velocity on the backside and the depth of the impression left on the surface from the high pressure plasma pulse created by the shock laser. To help quantify the stresses and strengths at the interface, a finite element model is being developed and validated by comparing numerical and experimental results for back face velocities and front face depressions with experimental results. This paper will report on initial efforts to develop a finite element model for laser shock.

James A. Smith; Jeffrey M. Lacy; Barry H. Rabin

2014-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "diffuse downwelling irradiance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


201

Forecasting Turbulent Modes with Nonparametric Diffusion Models  

E-Print Network [OSTI]

This paper presents a nonparametric diffusion modeling approach for forecasting partially observed noisy turbulent modes. The proposed forecast model uses a basis of smooth functions (constructed with the diffusion maps algorithm) to represent probability densities, so that the forecast model becomes a linear map in this basis. We estimate this linear map by exploiting a previously established rigorous connection between the discrete time shift map and the semi-group solution associated to the backward Kolmogorov equation. In order to smooth the noisy data, we apply diffusion maps to a delay embedding of the noisy data, which also helps to account for the interactions between the observed and unobserved modes. We show that this delay embedding biases the geometry of the data in a way which extracts the most predictable component of the dynamics. The resulting model approximates the semigroup solutions of the generator of the underlying dynamics in the limit of large data and in the observation noise limit. We will show numerical examples on a wide-range of well-studied turbulent modes, including the Fourier modes of the energy conserving Truncated Burgers-Hopf (TBH) model, the Lorenz-96 model in weakly chaotic to fully turbulent regimes, and the barotropic modes of a quasi-geostrophic model with baroclinic instabilities. In these examples, forecasting skills of the nonparametric diffusion model are compared to a wide-range of stochastic parametric modeling approaches, which account for the nonlinear interactions between the observed and unobserved modes with white and colored noises.

Tyrus Berry; John Harlim

2015-01-27T23:59:59.000Z

202

Diffusion in Energy Conserving Coupled Maps  

E-Print Network [OSTI]

We consider a dynamical system consisting of subsystems indexed by a lattice. Each subsystem has one conserved degree of freedom ("energy") the rest being uniformly hyperbolic. The subsystems are weakly coupled together so that the sum of the subsystem energies remains conserved. We prove that the subsystem energies satisfy the diffusion equation in a suitable scaling limit.

Jean Bricmont; Antti Kupiainen

2012-09-09T23:59:59.000Z

203

Ternary gas mixture for diffuse discharge switch  

DOE Patents [OSTI]

A new diffuse discharge gas switch wherein a mixture of gases is used to take advantage of desirable properties of the respective gases. There is a conducting gas, an insulating gas, and a third gas that has low ionization energy resulting in a net increase in the number of electrons available to produce a current.

Christophorou, Loucas G. (Oak Ridge, TN); Hunter, Scott R. (Oak Ridge, TN)

1988-01-01T23:59:59.000Z

204

Mathematical analysis for fractional diffusion equations: forward  

E-Print Network [OSTI]

or dumping WasteGroundwater flow Base rock Underground storage Soil gapsmicro scale about 100m Field: macro-Diffusion equation Result of Field Test (Adams& Gelhar, 1992) t0 t1 t2 t3 t0 Pollution source Model Prediction Univ. #12;· Determination of contamination source t u = u + F We need detailed mathematical researches

Boyer, Franck

205

Correcting the diffusion approximation at the boundary  

E-Print Network [OSTI]

, 2011 The diffusion approximation to the radiative transport equation applies for light that has solutions of the radiative transport equation to evaluate each of their accuracy. Nonetheless, nearly all transport equation · I þ aI þ sLI ¼ 0; ð1:1� governs continuous light propagation in tissues [1

Kim, Arnold D.

206

Original article Mannitol enhances intracellular calcium diffusion  

E-Print Network [OSTI]

concentration-dependent increase in the amount of calcium absor- bed in 1 h from 8 cm long ileal loops prepared-enhanced movement of calcium out of the loop cannot have utilized the paracellular pathway, inasmuch as the luminalOriginal article Mannitol enhances intracellular calcium diffusion in the rat ileum ­ a hypothesis

Paris-Sud XI, Université de

207

Metal Nitride Diffusion Barriers for Copper Interconnects  

E-Print Network [OSTI]

of copper into silicon, which is primarily through grain boundaries. This dissertation reports the processing of high quality stoichiometric thin films of TiN, TaN and HfN, and studies their Cu diffusion barrier properties. Epitaxial metastable cubic TaN (B1...

Araujo, Roy A.

2010-01-14T23:59:59.000Z

208

Open Source Software: Management, Diffusion and Competition  

E-Print Network [OSTI]

and competitive environment such as the ICT market. 1 Introduction OSS is an alternative model of software has introduced an innovative model of software development, based on self-organized communitiesOpen Source Software: Management, Diffusion and Competition Spyridoula Lakkaé National

Kouroupetroglou, Georgios

209

Materials Modification Under Ion Irradiation: JANNUS Project  

SciTech Connect (OSTI)

JANNUS (Joint Accelerators for Nano-Science and Nuclear Simulation) is a project designed to study the modification of materials using multiple ion beams and in-situ TEM observation. It will be a unique facility in Europe for the study of irradiation effects, the simulation of material damage due to irradiation and in particular of combined effects. The project is also intended to bring together experimental and modelling teams for a mutual fertilisation of their activities. It will also contribute to the teaching of particle-matter interactions and their applications. JANNUS will be composed of three accelerators with a common experimental chamber and of two accelerators coupled to a 200 kV TEM.

Serruys, Y.; Trocellier, P. [CEA-Saclay, DEN/DMN/SRMP, 91191 Gif-sur-Yvette Cedex (France); Ruault, M.-O.; Henry, S.; Kaietasov, O. [CSNSM, Bat. 104, Orsay Campus (France); Trouslard, Ph. [INSTN, CEA-Saclay, 91191 Gif-sur-Yvette Cedex (France)

2004-12-01T23:59:59.000Z

210

Comparison of Direct Normal Irradiance Derived from Silicon and Thermopile Global Hemispherical Radiation Detectors: Preprint  

SciTech Connect (OSTI)

Concentrating solar applications utilize direct normal irradiance (DNI) radiation, a measurement rarely available. The solar concentrator industry has begun to deploy numerous measurement stations to prospect for suitable system deployment sites. Rotating shadowband radiometers (RSR) using silicon photodiodes as detectors are typically deployed. This paper compares direct beam estimates from RSR to a total hemispherical measuring radiometer (SPN1) multiple fast thermopiles. These detectors simultaneously measure total and diffuse radiation from which DNI can be computed. Both the SPN1 and RSR-derived DNI are compared to DNI measured with thermopile pyrheliometers. Our comparison shows that the SPN1 radiometer DNI estimated uncertainty is somewhat greater than, and on the same order as, the RSR DNI estimates for DNI magnitudes useful to concentrator technologies.

Myers, D. R.

2010-01-01T23:59:59.000Z

211

Consideration of Grain Size Distribution in the Diffusion of Fission Gas to Grain Boundaries  

SciTech Connect (OSTI)

We analyze the accumulation of fission gas on grain boundaries in a polycrystalline microstructure with a distribution of grain sizes. The diffusion equation is solved throughout the microstructure to evolve the gas concentration in space and time. Grain boundaries are treated as infinite sinks for the gas concentration, and we monitor the cumulative gas inventory on each grain boundary throughout time. We consider two important cases: first, a uniform initial distribution of gas concentration without gas production (correlating with post-irradiation annealing), and second, a constant gas production rate with no initial gas concentration (correlating with in-reactor conditions). The results show that a single-grain-size model, such as the Booth model, over predicts the gas accumulation on grain boundaries compared with a polycrystal with a grain size distribution. Also, a considerable degree of scatter, or variability, exists in the grain boundary gas accumulation when comparing all of the grain boundaries in the microstructure.

Paul C. Millett; Yongfeng Zhang; Michael R. Tonks; S. B. Biner

2013-09-01T23:59:59.000Z

212

Neutron irradiation of beryllium: Recent Russian results  

SciTech Connect (OSTI)

Results on postirradiation tensile and compression testing, swelling and bubble growth during annealing for various grades of beryllium are presented. It is shown that swelling at temperatures above 550{degrees}C is sensitive to material condition and response is correlated with oxygen content. Swelling on the order of 15% can be expected at 700{degrees}C for doses on the order of 10{sup 22} n/cm{sup 2}. Bubble growth response depends on irradiation fluence.

Gelles, D.S. [Pacific Northwest Lab., Richland, VA (United States)

1992-12-31T23:59:59.000Z

213

ARM - Measurement - Shortwave broadband total net irradiance  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc Documentation RUC : XDCResearch Relatedcontent ARMnumberDoppler ARMdiffusedirectnet irradiance

214

ARM - Measurement - Shortwave narrowband direct normal irradiance  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc Documentation RUC : XDCResearch Relatedcontent ARMnumberDopplerdownwelling irradiance ARM

215

Upgrade to the Birmingham Irradiation Facility  

E-Print Network [OSTI]

The Birmingham Irradiation Facility was developed in 2013 at the University of Birmingham using the Medical Physics MC40 cyclotron. It can achieve High Luminosity LHC (HL-LHC) fluences of 10^15 (1 MeV neutron equivalent (neq)) cm^-2 in 80 s with proton beam currents of 1 ?A and so can evaluate effectively the performance and durability of detector technologies and new components to be used for the HL-LHC. Irradiations of silicon sensors and passive materials can be carried out in a temperature controlled cold box which moves continuously through the homogenous beamspot. This movement is provided by a pre-configured XY-axis Cartesian robot scanning system. In 2014 the cooling system and cold box were upgraded from a recirculating glycol chiller system to a liquid nitrogen evaporative system. The new cooling system achieves a stable temperature of 50 1C in 30 min and aims to maintain sub-0 1C temperatures on the sensors during irradiations. This paper reviews the design, development, commissioning and perform...

Dervan, P; Hodgson, P; Marin- Reyes; Parker, K; Wilson, J; Baca, M

2015-01-01T23:59:59.000Z

216

Probing the brain’s white matter with diffusion MRI and a tissue dependent diffusion model   

E-Print Network [OSTI]

While diffusion MRI promises an insight into white matter microstructure in vivo, the axonal pathways that connect different brain regions together can only partially be segmented using current methods. Here we present ...

Piatkowski, Jakub Przemyslaw

2014-06-27T23:59:59.000Z

217

Thermal transport in CO2 laser irradiated fused silica: in situ measurements and analysis  

SciTech Connect (OSTI)

In situ spatial and temporal temperature measurements of pristine fused silica surfaces heated with a 10.6 {micro}m CO{sub 2} laser were obtained using an infrared radiation thermometer based on a Mercury Cadmium Telluride (MCT) camera. Laser spot sizes ranged from 250 {micro}m to 1000 {micro}m diameter with peak axial irradiance levels of 0.13 to 16 kW/cm{sup 2}. For temperatures below 2800K, the measured steady-state surface temperature is observed to rise linearly with both increasing beam size and incident laser irradiance. The effective thermal conductivity estimated over this range was approximately 2W/mK, in good agreement with classical calculations based on phonon heat capacities. Similarly, time-dependent temperature measurements up to 2000K yielded thermal diffusivity values which were close to reported values of 7 x 10{sup -7} m{sup 2}/s. Above {approx}2800K, the fused silica surface temperature asymptotically approaches 3100K as laser power is further increased, consistent with the onset of evaporative heat losses near the silica boiling point. These results show that in the laser heating regime studied here, the T{sup 3} temperature dependent thermal conductivity due to radiation transport can be neglected, but at temperatures above 2800K heat transport due to evaporation must be considered. The thermal transport in fused silica up to 2800K, over a range of conditions, can then be adequately described by a linear diffusive heat equation assuming constant thermal properties.

Yang, S T; Matthews, M J; Elhadj, S; Draggoo, V G; Bisson, S E

2009-07-07T23:59:59.000Z

218

E-Print Network 3.0 - altered water diffusivity Sample Search...  

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

Emory University Collection: Materials Science ; Physics 47 Oxygen diffusion in titanite: Lattice diffusion and fast-path diffusion in single crystals Summary: , with little...

219

Moisture Diffusion in Asphalt Binders and Fine Aggregate Mixtures  

E-Print Network [OSTI]

cost in highway maintenance and vehicle operations. One key mechanism of how moisture reaches the asphalt-aggregate interface is by its permeation or diffusion through the asphalt binder or mastic. Different techniques are available for diffusion...

Vasconcelos, Kamilla L.

2011-08-08T23:59:59.000Z

220

Shell Model for Atomistic Simulation of Lithium Diffusion in...  

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

Shell Model for Atomistic Simulation of Lithium Diffusion in Mixed MnTi Oxides. Shell Model for Atomistic Simulation of Lithium Diffusion in Mixed MnTi Oxides. Abstract: Mixed...

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


221

A piecewise linear finite element discretization of the diffusion equation  

E-Print Network [OSTI]

it discretizes the diffusion equation on an arbitrary polyhedral mesh. We implemented our method in the KULL software package being developed at Lawrence Livermore National Laboratory. This code previously utilized Palmer's method as its diffusion solver, which...

Bailey, Teresa S

2006-10-30T23:59:59.000Z

222

Modelling of unidirectional thermal diffusers in shallow water  

E-Print Network [OSTI]

This study is an experimental and theoretical investigation of the temperature field and velocity field induced by a unidirectional thermal diffuser in shallow water. A multiport thermal diffuser is essentially a pipe laid ...

Lee, Joseph Hun-Wei

1977-01-01T23:59:59.000Z

223

Imaging Intrinsic Diffusion of Bridge-Bonded Oxygen Vacancies...  

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

Intrinsic Diffusion of Bridge-Bonded Oxygen Vacancies on TiO2(110). Imaging Intrinsic Diffusion of Bridge-Bonded Oxygen Vacancies on TiO2(110). Abstract: Since oxygen atom...

224

Sensitivity of climate change to diapycnal diffusivity in the ocean  

E-Print Network [OSTI]

The diapycnal diffusivity of the ocean is one of the least known parameters in cur- rent climate models. Measurements of this diffusivity are sparse and insufficient for compiling a global map. Inferences from inverse ...

Dalan, Fabio, 1975-

2003-01-01T23:59:59.000Z

225

Quantitative analysis of cerebral white matter anatomy from diffusion MRI  

E-Print Network [OSTI]

In this thesis we develop algorithms for quantitative analysis of white matter fiber tracts from diffusion MRI. The presented methods enable us to look at the variation of a diffusion measure along a fiber tract in a single ...

Maddah, Mahnaz

2008-01-01T23:59:59.000Z

226

CODED SPECTROSCOPY FOR ETHANOL DETECTION IN DIFFUSE, FLUORESCENT MEDIA  

E-Print Network [OSTI]

ABSTRACT CODED SPECTROSCOPY FOR ETHANOL DETECTION IN DIFFUSE, FLUORESCENT MEDIA by Scott Thomas Mc FOR ETHANOL DETECTION IN DIFFUSE, FLUORESCENT MEDIA by Scott Thomas McCain Department of Electrical

227

The spectral irradiance traceability chain at PTB  

SciTech Connect (OSTI)

Spectral irradiance is a fundamental radiometric unit. Its application to measurement results requires qualified traceability to basic units of the international system of units (Systeme international d'unites, SI). The Physikalisch-Technische Bundesanstalt (PTB) is amongst other national metrological institutes (NMIs) responsible for the realization, maintenance and dissemination of various radiometric and photometric units based on and traceable to national standards. The unit of spectral irradiance is realized and represented by a blackbody-radiator as the national primary standard of the PTB. Based on Planck's radiation law, the irradiance is calculated and realized for any wavelength taking into account the exact knowledge of the radiation temperature and the geometrical parameters. Using a double-monochromator-based spectroradiometer system, secondary standard lamps can be calibrated by direct comparison to the blackbody-radiator (substitution method). These secondary standard lamps are then used at the PTB to calibrate standard lamps of customers. The customers themselves use these so-called transfer standards to calibrate their working standard lamps. These working standards are then used to calibrate own spectroradiometers or sources. This rather complex calibration chain is a common procedural method that for the customers generally leads to satisfying measurement results on site. Nevertheless, the standard lamps in use have to fulfill highest requirements concerning stability and reproducibility. Only this allows achieving comparably low transfer measurement uncertainties, which occur at each calibration step. Thus, the PTB is constantly investigating the improvement and further development of transfer standards and measurement methods for various spectral regions. The realization and dissemination of the spectral irradiance using the blackbody-radiator at the PTB is accomplished with worldwide approved minimized measurement uncertainties confirmed by international intercomparisons among NMIs. Ultimately, the spectral irradiance can be realized with expanded measurement uncertainties of far less than 1 % over a wide spectral range. Thus, for customers with high demands on low measurement uncertainties, it is possible to calibrate their working standards directly against the blackbody-radiator, taking into account the higher necessary effort. In special cases it is possible to calibrate the customer's spectroradiometric facilities directly in front of the blackbody-radiator. In the context of the European Metrology Research Project Traceability for surface spectral solar ultraviolet radiation, the traceability chain will be improved and adapted.

Sperfeld, P.; Pape, S.; Nevas, S. [Physikalisch-Technische Bundesanstalt, Bundesallee 10, 381160 Braunschweig (Germany)

2013-05-10T23:59:59.000Z

228

Evaluation of Neutron Irradiated Silicon Carbide and Silicon Carbide Composites  

SciTech Connect (OSTI)

The effects of fast neutron irradiation on SiC and SiC composites have been studied. The materials used were chemical vapor deposition (CVD) SiC and SiC/SiC composites reinforced with either Hi-Nicalon{trademark} Type-S, Hi-Nicalon{trademark} or Sylramic{trademark} fibers fabricated by chemical vapor infiltration. Statistically significant numbers of flexural samples were irradiated up to 4.6 x 10{sup 25} n/m{sup 2} (E>0.1 MeV) at 300, 500 and 800 C in the High Flux Isotope Reactor at Oak Ridge National Laboratory. Dimensions and weights of the flexural bars were measured before and after the neutron irradiation. Mechanical properties were evaluated by four point flexural testing. Volume increase was seen for all bend bars following neutron irradiation. Magnitude of swelling depended on irradiation temperature and material, while it was nearly independent of irradiation fluence over the fluence range studied. Flexural strength of CVD SiC increased following irradiation depending on irradiation temperature. Over the temperature range studied, no significant degradation in mechanical properties was seen for composites fabricated with Hi-Nicalon{trademark} Type-S, while composites reinforced with Hi-Nicalon{trademark} or Sylramic fibers showed significant degradation. The effects of irradiation on the Weibull failure statistics are also presented suggesting a reduction in the Weibull modulus upon irradiation. The cause of this potential reduction is not known.

Newsome G, Snead L, Hinoki T, Katoh Y, Peters D

2007-03-26T23:59:59.000Z

229

A 20-Year Dataset of Downwelling Longwave Flux at the Arctic Surface from TOVS Satellite Data  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNGExperience hands-onASTROPHYSICSHe β- DecayBenew20-Year Dataset of

230

A New Method and Results of Estimating Areal-Mean Spectral Surface Albedo from Downwelling  

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

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231

Techniques and Methods Used to Determine the Best Estimate of Total Downwelling Shortwave Radiation  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security AdministrationcontrollerNanocrystallineForeign ObjectOUR8,Materials Characterization TechniqueDetermine

232

LETTRES A LA RDACTION DIFFUSION LASTIQUE DES PHOTONS  

E-Print Network [OSTI]

spectrometrie par scintillation 6choue, 6 cause des empilements de photons diffus6s de basse énergie. FIG. 1

Paris-Sud XI, Université de

233

X-Ray Energy Responses of Silicon Tomography Detectors Irradiated with Fusion Produced Neutrons  

SciTech Connect (OSTI)

In order to clarify the effects of fusion-produced neutron irradiation on silicon semiconductor x-ray detectors, the x-ray energy responses of both n- and p-type silicon tomography detectors used in the Joint European Torus (JET) tokamak (n-type) and the GAMMA 10 tandem mirror (p-type) are studied using synchrotron radiation at the Photon Factory of the National Laboratory for High Energy Accelerator Research Organization (KEK). The fusion neutronics source (FNS) of Japan Atomic Energy Research Institute (JAERI) is employed as well-calibrated D-T neutron source with fluences from 10{sup 13} to 10{sup 15} neutrons/cm{sup 2} onto these semiconductor detectors. Different fluence dependence is found between these two types of detectors; that is, (i) for the n-type detector, the recovery of the degraded response is found after the neutron exposure beyond around 10{sup 13} neutrons/cm{sup 2} onto the detector. A further finding is followed as a 're-degradation' by a neutron irradiation level over about 10{sup 14} neutrons/cm{sup 2}. On the other hand, (ii) the energy response of the p-type detector shows only a gradual decrease with increasing neutron fluences. These properties are interpreted by our proposed theory on semiconductor x-ray responses in terms of the effects of neutrons on the effective doping concentration and the diffusion length of a semiconductor detector.

Kohagura, J. [Plasma Research Centre, University of Tsukuba (Japan); Cho, T. [Plasma Research Centre, University of Tsukuba (Japan); Hirata, M. [Plasma Research Centre, University of Tsukuba (Japan); Numakura, T. [Plasma Research Centre, University of Tsukuba (Japan); Yokoyama, N. [Plasma Research Centre, University of Tsukuba (Japan); Fukai, T. [Plasma Research Centre, University of Tsukuba (Japan); Tomii, Y. [Plasma Research Centre, University of Tsukuba (Japan); Tokioka, S. [Plasma Research Centre, University of Tsukuba (Japan); Miyake, Y. [Plasma Research Centre, University of Tsukuba (Japan); Kiminami, S. [Plasma Research Centre, University of Tsukuba (Japan); Shimizu, K. [Plasma Research Centre, University of Tsukuba (Japan); Miyoshi, S. [Plasma Research Centre, University of Tsukuba (Japan); Hirano, K. [High Energy Accelerator Research Organization (Japan); Yoshida, M. [Japan Atomic Energy Research Institute (Japan); Yamauchi, M. [Japan Atomic Energy Research Institute (Japan); Kondoh, T. [Japan Atomic Energy Research Institute (Japan); Nishitani, T. [Japan Atomic Energy Research Institute (Japan)

2005-01-15T23:59:59.000Z

234

Convergence Speed of GARCH Option Price to Diffusion Option Price  

E-Print Network [OSTI]

Convergence Speed of GARCH Option Price to Diffusion Option Price Jin-Chuan Duan National constructed GARCH model will weakly converge to a bi- variate diffusion. Naturally the European option price under the GARCH model will also converge to its bivariate diffusion counterpart. This paper investigates

Wang, Yazhen

235

Diffusion Bonding Aluminium Alloys and Composites: New Approaches and Modelling  

E-Print Network [OSTI]

Diffusion Bonding Aluminium Alloys and Composites: New Approaches and Modelling Amir A. Shirzadi of the research, two new methods for TLP diffusion bonding of aluminium-based composites (aluminium alloys diffusion bonding and hot isostatic pressing without encapsulation. It allows the fabrication of intricate

Cambridge, University of

236

EFFECT OF BROWNIAN AND THERMOPHORETIC DIFFUSIONS OF NANOPARTICLES ON  

E-Print Network [OSTI]

EFFECT OF BROWNIAN AND THERMOPHORETIC DIFFUSIONS OF NANOPARTICLES ON NONEQUILIBRIUM HEAT CONDUCTION of Brownian and thermophoretic diffusions on nonequilibrium heat conduction in a nanofluid layer with periodic, and period of the surface heat flux. Effects of Brownian and thermophoretic diffusions of nanoparticles

Zhang, Yuwen

237

Nonlinear analysis of a reaction-diffusion system: Amplitude equations  

SciTech Connect (OSTI)

A reaction-diffusion system with a nonlinear diffusion term is considered. Based on nonlinear analysis, the amplitude equations are obtained in the cases of the Hopf and Turing instabilities in the system. Turing pattern-forming regions in the parameter space are determined for supercritical and subcritical instabilities in a two-component reaction-diffusion system.

Zemskov, E. P., E-mail: zemskov@ccas.ru [Russian Academy of Sciences, Dorodnicyn Computing Center (Russian Federation)

2012-10-15T23:59:59.000Z

238

ORIGINAL PAPER Assimilation and diffusion during xenolith-magma  

E-Print Network [OSTI]

(responsible for the linear mixing trends) and (2) diffusion-controlled redistribution of elements between bothORIGINAL PAPER Assimilation and diffusion during xenolith-magma interaction: a case study the assimilation of granitic melt. Linear mixing trends on Harker diagrams for most network-forming and mainly slow-diffusing

Podladchikov, Yuri

239

Parallel computation safety analysis irradiation targets fission product molybdenum in neutronic aspect using the successive over-relaxation algorithm  

SciTech Connect (OSTI)

One of the research activities in support of commercial radioisotope production program is a safety research on target FPM (Fission Product Molybdenum) irradiation. FPM targets form a tube made of stainless steel which contains nuclear-grade high-enrichment uranium. The FPM irradiation tube is intended to obtain fission products. Fission materials such as Mo{sup 99} used widely the form of kits in the medical world. The neutronics problem is solved using first-order perturbation theory derived from the diffusion equation for four groups. In contrast, Mo isotopes have longer half-lives, about 3 days (66 hours), so the delivery of radioisotopes to consumer centers and storage is possible though still limited. The production of this isotope potentially gives significant economic value. The criticality and flux in multigroup diffusion model was calculated for various irradiation positions and uranium contents. This model involves complex computation, with large and sparse matrix system. Several parallel algorithms have been developed for the sparse and large matrix solution. In this paper, a successive over-relaxation (SOR) algorithm was implemented for the calculation of reactivity coefficients which can be done in parallel. Previous works performed reactivity calculations serially with Gauss-Seidel iteratives. The parallel method can be used to solve multigroup diffusion equation system and calculate the criticality and reactivity coefficients. In this research a computer code was developed to exploit parallel processing to perform reactivity calculations which were to be used in safety analysis. The parallel processing in the multicore computer system allows the calculation to be performed more quickly. This code was applied for the safety limits calculation of irradiated FPM targets containing highly enriched uranium. The results of calculations neutron show that for uranium contents of 1.7676 g and 6.1866 g (× 10{sup 6} cm{sup ?1}) in a tube, their delta reactivities are the still within safety limits; however, for 7.9542 g and 8.838 g (× 10{sup 6} cm{sup ?1}) the limits were exceeded.

Susmikanti, Mike, E-mail: mike@batan.go.id [Center for Development of Nuclear Informatics, National Nuclear Energy Agency, PUSPIPTEK, Tangerang (Indonesia); Dewayatna, Winter, E-mail: winter@batan.go.id [Center for Nuclear Fuel Technology, National Nuclear Energy Agency, PUSPIPTEK, Tangerang (Indonesia); Sulistyo, Yos, E-mail: soj@batan.go.id [Center for Nuclear Equipment and Engineering, National Nuclear Energy Agency, PUSPIPTEK, Tangerang (Indonesia)

2014-09-30T23:59:59.000Z

240

Diffusion limited reactions in confined environments  

E-Print Network [OSTI]

We study the effect of confinement on diffusion limited bimolecular reactions within a lattice model where a small number of reactants diffuse amongst a much larger number of inert particles. When the number of inert particles is held constant the rate of the reaction is slow for small reaction volumes due to limited mobility from crowding, and for large reaction volumes due to the reduced concentration of the reactants. The reaction rate proceeds fastest at an intermediate confinement corresponding to volume fraction near 1/2 and 1/3 in two and three dimensions, respectively. We generalize the model to off-lattice systems with hydrodynamic coupling and predict that the optimal reaction rate for monodisperse colloidal systems occurs when the volume fraction is ~0.18. Finally, we discuss the application of our model to bimolecular reactions inside cells as well as the dynamics of confined polymers.

Jeremy D. Schmit; Ercan Kamber; Jané Kondev

2007-11-19T23:59:59.000Z

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


241

Diffusion barriers in modified air brazes  

DOE Patents [OSTI]

A method for joining two ceramic parts, or a ceramic part and a metal part, and the joint formed thereby. The method provides two or more parts, a braze consisting of a mixture of copper oxide and silver, a diffusion barrier, and then heats the braze for a time and at a temperature sufficient to form the braze into a bond holding the two or more parts together. The diffusion barrier is an oxidizable metal that forms either a homogeneous component of the braze, a heterogeneous component of the braze, a separate layer bordering the braze, or combinations thereof. The oxidizable metal is selected from the group Al, Mg, Cr, Si, Ni, Co, Mn, Ti, Zr, Hf, Pt, Pd, Au, lanthanides, and combinations thereof.

Weil, Kenneth Scott; Hardy, John S; Kim, Jin Yong; Choi, Jung-Pyung

2013-04-23T23:59:59.000Z

242

Efficiency limits of diffusive shock acceleration  

E-Print Network [OSTI]

It is well accepted today that diffusive acceleration in shocks results to the cosmic ray spectrum formation. This is in principle true for non-relativistic shocks, since there is a detailed theory covering a large range of their properties and the resulting power-law spectrum, which is nevertheless not as efficient to reach the very high energies observed in the cosmic ray spectrum. On the other hand, the cosmic ray maximum energy and the resulting spectra from relativistic shocks, are still under investigation and debate concerning their contribution to the features of the cosmic ray spectrum and the measured, or implied, cosmic ray radiation from candidate astrophysical sources. Here, we discuss the efficiency of the first order Fermi (diffusive) acceleration mechanism up to relativistic shock speeds, presenting Monte Carlo simulations.

A. Meli; A. Mastichiadis

2007-08-10T23:59:59.000Z

243

Diffusion barriers in modified air brazes  

DOE Patents [OSTI]

A method for joining two ceramic parts, or a ceramic part and a metal part, and the joint formed thereby. The method provides two or more parts, a braze consisting of a mixture of copper oxide and silver, a diffusion barrier, and then heats the braze for a time and at a temperature sufficient to form the braze into a bond holding the two or more parts together. The diffusion barrier is an oxidizable metal that forms either a homogeneous component of the braze, a heterogeneous component of the braze, a separate layer bordering the braze, or combinations thereof. The oxidizable metal is selected from the group Al, Mg, Cr, Si, Ni, Co, Mn, Ti, Zr, Hf, Pt, Pd, Au, lanthanides, and combinations thereof.

Weil, Kenneth Scott (Richland, WA); Hardy, John S. (Richland, WA); Kim, Jin Yong (Richland, WA); Choi, Jung-Pyung (Richland, WA)

2010-04-06T23:59:59.000Z

244

Methodology and apparatus for diffuse photon mimaging  

DOE Patents [OSTI]

Non-invasive near infrared optical medical imaging devices for both hematoma detection in the brain and early tumor detection in the breast is achieved using image reconstruction which allows a mapping of the position dependent contrast diffusive propagation constants, which are related to the optical absorption coefficient and scattering coefficient in the tissue, at near infrared wavelengths. Spatial resolutions in the range of 5 mm for adult brain sizes and breast sizes can be achieved. The image reconstruction utilizes WKB approximation on most probable diffusion paths which has as lowest order approximation the straight line-of-sight between the plurality of sources and the plurality of detectors. The WKB approximation yields a set of linear equations in which the contrast optical absorption coefficients are the unknowns and for which signals can be generated to produce a pixel map of the contrast optical resolution of the scanned tissue.

Feng, Shechao C. (Los Angeles, CA); Zeng, Fanan (Los Angeles, CA); Zhao, Hui-Lin (Los Angeles, CA)

1997-12-09T23:59:59.000Z

245

Methodology and apparatus for diffuse photon imaging  

DOE Patents [OSTI]

Non-invasive near infrared optical medical imaging devices for both hematoma detection in the brain and early tumor detection in the breast is achieved using image reconstruction which allows a mapping of the position dependent contrast diffusive propagation constants, which are related to the optical absorption coefficient and scattering coefficient in the tissue, at near infrared wavelengths. Spatial resolutions in the range of 5 mm for adult brain sizes and breast sizes can be achieved. The image reconstruction utilizes WKB approximation on most probable diffusion paths which has as lowest order approximation the straight line-of-sight between the plurality of sources and the plurality of detectors. The WKB approximation yields a set of linear equations in which the contrast optical absorption coefficients are the unknowns and for which signals can be generated to produce a pixel map of the contrast optical resolution of the scanned tissue. 58 figs.

Feng, S.C.; Zeng, F.; Zhao, H.L.

1997-12-09T23:59:59.000Z

246

Glass Membrane For Controlled Diffusion Of Gases  

DOE Patents [OSTI]

A glass structure for controlled permeability of gases includes a glass vessel. The glass vessel has walls and a hollow center for receiving a gas. The glass vessel contains a metal oxide dopant formed with at least one metal selected from the group consisting of transition metals and rare earth metals for controlling diffusion of the gas through the walls of the glass vessel. The vessel releases the gas through its walls upon exposure to a radiation source.

Shelby, James E. (Alfred Station, NY); Kenyon, Brian E. (Pittsburgh, PA)

2001-05-15T23:59:59.000Z

247

Diffuse-dynamic multiparameter diffractometry: A review  

SciTech Connect (OSTI)

The results reported at the Conference on Application of X-Rays, Synchrotron Radiation, Neutrons, and Electrons in Nano-, Bio-, Information-, and Cognitive Technologies (RSNE-NBIC 2009) are briefly reviewed. This review is based on a cycle of studies [1-6] where a new method for studying the structure of real crystals-diffuse-dynamic multiparameter diffractometry (DDMD)-was proposed and substantiated.

Molodkin, V. B., E-mail: molodkn@imp.kiev.ua; Shpak, A. P. [National Academy of Sciences of Ukraine, Institute of Metal Physics (Ukraine); Kovalchuk, M. V.; Nosik, V. L. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Machulin, V. F. [National Academy of Sciences of Ukraine, Institute of Semiconductor Physics (Ukraine)

2010-12-15T23:59:59.000Z

248

Diffusion method of seperating gaseous mixtures  

DOE Patents [OSTI]

A method of effecting a relatively large change in the relative concentrations of the components of a gaseous mixture by diffusion which comprises separating the mixture into heavier and lighter portions according to major fraction mass recycle procedure, further separating the heavier portions into still heavier subportions according to a major fraction mass recycle procedure, and further separating the lighter portions into still lighter subportions according to a major fraction equilibrium recycle procedure.

Pontius, Rex B. (Rochester, NY)

1976-01-01T23:59:59.000Z

249

Gas mixture for diffuse-discharge switch  

DOE Patents [OSTI]

Gaseous medium in a diffuse-discharge switch of a high-energy pulse generator is formed of argon combined with a compound selected from the group consisting of CF/sub 4/, C/sub 2/F/sub 6/, C/sub 3/F/sub 8/, n-C/sub 4/F/sub 10/, WF/sub 6/, (CF/sub 3/)/sub 2/S and (CF/sub 3/)/sub 2/O.

Christophorou, L.G.; Carter, J.G.; Hunter, S.R.

1982-08-31T23:59:59.000Z

250

Uranium enrichment export control guide: Gaseous diffusion  

SciTech Connect (OSTI)

This document was prepared to serve as a guide for export control officials in their interpretation, understanding, and implementation of export laws that relate to the Zangger International Trigger List for gaseous diffusion uranium enrichment process components, equipment, and materials. Particular emphasis is focused on items that are especially designed or prepared since export controls are required for these by States that are party to the International Nuclear Nonproliferation Treaty.

Not Available

1989-09-01T23:59:59.000Z

251

Diffuse-Charge Dynamics in Electrochemical Systems  

E-Print Network [OSTI]

The response of a model micro-electrochemical system to a time-dependent applied voltage is analyzed. The article begins with a fresh historical review including electrochemistry, colloidal science, and microfluidics. The model problem consists of a symmetric binary electrolyte between parallel-plate, blocking electrodes which suddenly apply a voltage. Compact Stern layers on the electrodes are also taken into account. The Nernst-Planck-Poisson equations are first linearized and solved by Laplace transforms for small voltages, and numerical solutions are obtained for large voltages. The ``weakly nonlinear'' limit of thin double layers is then analyzed by matched asymptotic expansions in the small parameter $\\epsilon = \\lambda_D/L$, where $\\lambda_D$ is the screening length and $L$ the electrode separation. At leading order, the system initially behaves like an RC circuit with a response time of $\\lambda_D L / D$ (not $\\lambda_D^2/D$), where $D$ is the ionic diffusivity, but nonlinearity violates this common picture and introduce multiple time scales. The charging process slows down, and neutral-salt adsorption by the diffuse part of the double layer couples to bulk diffusion at the time scale, $L^2/D$. In the ``strongly nonlinear'' regime (controlled by a dimensionless parameter resembling the Dukhin number), this effect produces bulk concentration gradients, and, at very large voltages, transient space charge. The article concludes with an overview of more general situations involving surface conduction, multi-component electrolytes, and Faradaic processes.

Martin Z. Bazant; Katsuyo Thornton; Armand Ajdari

2004-01-08T23:59:59.000Z

252

Anomalous diffusion modifies solar neutrino fluxes  

E-Print Network [OSTI]

Density and temperature conditions in the solar core suggest that the microscopic diffusion of electrons and ions could be nonstandard: Diffusion and friction coefficients are energy dependent, collisions are not two-body processes and retain memory beyond the single scattering event. A direct consequence of nonstandard diffusion is that the equilibrium energy distribution of particles departs from the Maxwellian one (tails goes to zero more slowly or faster than exponentially) modifying the reaction rates. This effect is qualitatively different from temperature and/or composition modification: Small changes in the number of particles in the distribution tails can strongly modify the rates without affecting bulk properties, such as the sound speed or hydrostatic equilibrium, which depend on the mean values from the distribution. This mechanism can considerably increase the range of predictions for the neutrino fluxes allowed by the current experimental values (cross sections and solar properties) and can be used to reduce the discrepancy between these predictions and the solar neutrino experiments.

G. Kaniadakis; A. Lavagno; M. Lissia; P. Quarati

1997-10-16T23:59:59.000Z

253

A diffuse interface model with immiscibility preservation  

SciTech Connect (OSTI)

A new, simple, and computationally efficient interface capturing scheme based on a diffuse interface approach is presented for simulation of compressible multiphase flows. Multi-fluid interfaces are represented using field variables (interface functions) with associated transport equations that are augmented, with respect to an established formulation, to enforce a selected interface thickness. The resulting interface region can be set just thick enough to be resolved by the underlying mesh and numerical method, yet thin enough to provide an efficient model for dynamics of well-resolved scales. A key advance in the present method is that the interface regularization is asymptotically compatible with the thermodynamic mixture laws of the mixture model upon which it is constructed. It incorporates first-order pressure and velocity non-equilibrium effects while preserving interface conditions for equilibrium flows, even within the thin diffused mixture region. We first quantify the improved convergence of this formulation in some widely used one-dimensional configurations, then show that it enables fundamentally better simulations of bubble dynamics. Demonstrations include both a spherical-bubble collapse, which is shown to maintain excellent symmetry despite the Cartesian mesh, and a jetting bubble collapse adjacent a wall. Comparisons show that without the new formulation the jet is suppressed by numerical diffusion leading to qualitatively incorrect results.

Tiwari, Arpit, E-mail: atiwari2@illinois.edu [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)] [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Freund, Jonathan B., E-mail: jbfreund@illinois.edu [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Department of Aerospace Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Pantano, Carlos [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)] [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

2013-11-01T23:59:59.000Z

254

Interactive Volume Rendering of Diffusion Tensor Data  

SciTech Connect (OSTI)

As 3D volumetric images of the human body become an increasingly crucial source of information for the diagnosis and treatment of a broad variety of medical conditions, advanced techniques that allow clinicians to efficiently and clearly visualize volumetric images become increasingly important. Interaction has proven to be a key concept in analysis of medical images because static images of 3D data are prone to artifacts and misunderstanding of depth. Furthermore, fading out clinically irrelevant aspects of the image while preserving contextual anatomical landmarks helps medical doctors to focus on important parts of the images without becoming disoriented. Our goal was to develop a tool that unifies interactive manipulation and context preserving visualization of medical images with a special focus on diffusion tensor imaging (DTI) data. At each image voxel, DTI provides a 3 x 3 tensor whose entries represent the 3D statistical properties of water diffusion locally. Water motion that is preferential to specific spatial directions suggests structural organization of the underlying biological tissue; in particular, in the human brain, the naturally occuring diffusion of water in the axon portion of neurons is predominantly anisotropic along the longitudinal direction of the elongated, fiber-like axons [MMM+02]. This property has made DTI an emerging source of information about the structural integrity of axons and axonal connectivity between brain regions, both of which are thought to be disrupted in a broad range of medical disorders including multiple sclerosis, cerebrovascular disease, and autism [Mos02, FCI+01, JLH+99, BGKM+04, BJB+03].

Hlawitschka, Mario; Weber, Gunther; Anwander, Alfred; Carmichael, Owen; Hamann, Bernd; Scheuermann, Gerik

2007-03-30T23:59:59.000Z

255

Multicomponent Gas Diffusion in Porous Electrodes  

E-Print Network [OSTI]

Multicomponent gas transport is investigated with unprecedented precision by AC impedance analysis of porous YSZ anode-supported solid oxide fuel cells. A fuel gas mixture of H2-H2O-N2 is fed to the anode, and impedance data are measured across the range of hydrogen partial pressure (10-100%) for open circuit conditions at three temperatures (800C, 850C and 900C) and for 300mA applied current at 800C. For the first time, analytical formulae for the diffusion resistance (Rb) of three standard models of multicomponent gas transport (Fick, Stefan-Maxwell, and Dusty Gas) are derived and tested against the impedance data. The tortuosity is the only fitting parameter since all the diffusion coefficients are known. Only the Dusty Gas model leads to a remarkable data collapse for over twenty experimental conditions, using a constant tortuosity consistent with permeability measurements and the Bruggeman relation. These results establish the accuracy of the Dusty Gas model for multicomponent gas diffusion in porous med...

Fu, Yeqing; Dutta, Abhijit; Mohanram, Aravind; Pietras, John D; Bazant, Martin Z

2014-01-01T23:59:59.000Z

256

Josephson Junctions and Devices fabricated by Focused Electron Beam Irradiation  

E-Print Network [OSTI]

Josephson Junctions and Devices fabricated by Focused Electron Beam Irradiation Wilfred Edwin Booij Gonville and Caius College Cambridge A dissertation submitted for the degree of Doctor of Philosophy at the University of Cambridge December 1997... Summary Josephson Junctions and Devices fabricated by Focused Electron Beam Irradiation The irradiation of high Tc superconducting thin films with a focused electron beam, such as that obtained in a scanning transmission electron microscope (STEM), can...

Booij, Wilfred Edwin

257

A Simplified Shuttle Irradiation Facility for ATR  

SciTech Connect (OSTI)

During the past fifteen years there has been a steady increase in the demand for radioisotopes in nuclear medicine and a corresponding decline in the number of reactors within the U.S. capable of producing them. The Advanced Test Reactor (ATR) is the largest operating test reactor in the U.S., but its isotope production capabilities have been limited by the lack of an installed isotope shuttle irradiation system. A concept for a simple “low cost” shuttle irradiation facility for ATR has been developed. Costs were reduced (in comparison to previous ATR designs) by using a shielded trough of water installed in an occupiable cubicle as a shielding and contamination control barrier for the send and receive station. This shielding concept also allows all control valves to be operated by hand and thus the need for an automatic control system was eliminated. It was determined that 4 – 5 ft of water would be adequate to shield the isotopes of interest while shuttles are transferred to a small carrier. An additional feature of the current design is a non-isolatable by-pass line, which provides a minimum coolant flow to the test region regardless of which control valves are opened or closed. This by-pass line allows the shuttle facility to be operated without bringing reactor coolant water into the cubicle except for send and receive operations. The irradiation position selected for this concept is a 1.5 inch “B” hole (B-11). This position provides neutron fluxes of approximately: 1.6 x 1014 (<0.5 eV) and 4.0 x 1013 (>0.8 MeV) n/cm2*sec.

Palmer, Alma Joseph; Laflin, S. T.

1999-09-01T23:59:59.000Z

258

Emulation of reactor irradiation damage using ion beams  

SciTech Connect (OSTI)

The continued operation of existing light water nuclear reactors and the development of advanced nuclear reactor depend heavily on understanding how damage by radiation to levels degrades materials that serve as the structural components in reactor cores. The first high dose ion irradiation experiments on a ferritic-martensitic steel showing that ion irradiation closely emulates the full radiation damage microstructure created in-reactor are described. Ferritic-martensitic alloy HT9 (heat 84425) in the form of a hexagonal fuel bundle duct (ACO-3) accumulated 155 dpa at an average temperature of 443°C in the Fast Flux Test Facility (FFTF). Using invariance theory as a guide, irradiation of the same heat was conducted using self-ions (Fe++) at 5 MeV at a temperature of 460°C and to a dose of 188 displacements per atom. The void swelling was nearly identical between the two irradiations and the size and density of precipitates and loops following ion irradiation are within a factor of two of those for neutron irradiation. The level of agreement across all of the principal microstructure changes between ion and reactor irradiations establishes the capability of tailoring ion irradiations to emulate the reactor-irradiated microstructure.

G. S. Was; Z. Jiao; E. Beckett; A. M. Monterrosa; O. Anderoglu; B. H. Sencer; M. Hackett

2014-10-01T23:59:59.000Z

259

apres irradiation globale: Topics by E-print Network  

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

necessary for the evaluation of global irradiance on inclined surface which is needed for photovoltaic Boyer, Edmond 7 Caractristiques lectriques de diodes Au-Si(N) ralises aprs...

260

Microsoft Word - Analysis of Deformation Mode Changes in Irradiated...  

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

steels); however, in many cases they may have a negative impact on material performance (hydrogen embrittlement of bcc-phase, etc.). Irradiation leads to defects accumulation,...

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


261

Irradiation Effects on Human Cortical Bone Fracture Behavior  

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

Irradiation Effects on Human Cortical Bone Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic...

262

alpha particle irradiation: Topics by E-print Network  

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

5 Incidence characteristics of alpha particles on detectors irradiated in a radon progeny atmosphere Biology and Medicine Websites Summary: Incidence characteristics of...

263

alpha particles irradiation: Topics by E-print Network  

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

5 Incidence characteristics of alpha particles on detectors irradiated in a radon progeny atmosphere Biology and Medicine Websites Summary: Incidence characteristics of...

264

alpha particle irradiated: Topics by E-print Network  

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

5 Incidence characteristics of alpha particles on detectors irradiated in a radon progeny atmosphere Biology and Medicine Websites Summary: Incidence characteristics of...

265

apres irradiation alpha: Topics by E-print Network  

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

Edmond 8 Incidence characteristics of alpha particles on detectors irradiated in a radon progeny atmosphere Biology and Medicine Websites Summary: Incidence characteristics of...

266

Modification of Defect Structures in Graphene by Electron Irradiation...  

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

Modification of Defect Structures in Graphene by Electron Irradiation: Ab Initio Molecular Dynamics Simulations. Modification of Defect Structures in Graphene by Electron...

267

Dynamic Recovery in Silicate-Apatite Structures Under Irradiation...  

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

Recovery in Silicate-Apatite Structures Under Irradiation and Implications for Long-Term Immobilization of Actinides. Dynamic Recovery in Silicate-Apatite Structures Under...

268

Microstructural examination of irradiated vanadium alloys  

SciTech Connect (OSTI)

Microstructural examination results are reported for a V-5Cr-5Ti unirradiated control specimens of heat BL-63 following annealing at 1050{degrees}C, and V-4Cr-4Ti heat BL-47 irradiated in three conditions from the DHCE experiment: at 425{degrees}C to 31 dpa and 0.39 appm He/dpa, at 600{degrees}C to 18 dpa and 0.54 appm He/dpa and at 600{degrees}C to 18 dpa and 4.17 appm He/dpa.

Gelles, D.S. [Pacific Northwest National Lab., Richland, WA (United States); Chung, H.M. [Argonne National Lab., IL (United States)

1997-04-01T23:59:59.000Z

269

Mitigation of irradiation embrittlement by annealing  

SciTech Connect (OSTI)

The main results of a complex investigation carried out in Russia of post irradiation annealing and reembrittlement of WWER-440 reactor pressure vessel materials are presented. The dependence of the Charpy transition temperature recovery on annealing temperature and fluence was established. Charpy specimens were reirradiated after annealing at 340, 380, 420, and 460 C. Experimental values of the Charpy transition temperature after reirradiation are compared to that predicted by three methods. At annealing temperatures equal to or above 420 C, results of the analysis indicate that, of the methods investigated, the lateral shift method gives the best result for estimating the transition temperature shift due to reirradiation.

Amayev, A.D.; Kryukov, A.M.; Levit, V.I.; Platonov, P.A.; Sokolov, M.A. [Kurchatov Inst., Moscow (Russian Federation)

1996-12-31T23:59:59.000Z

270

Irradiation-induced effects of proton irradiation on zirconium carbides with different stoichiometries  

SciTech Connect (OSTI)

Zirconium carbide (ZrC) is being considered for utilization in deep burn TRISO fuel particles for hightemperature, gas-cooled reactors. Zirconium carbide has a cubic B1 type crystal structure along with a very high melting point (3420 ?C), exceptional hardness and good thermal and electrical conductivities. Understanding the ZrC irradiation response is crucial for establishing ZrC as an alternative component in TRISO fuel. Until now, very few studies on irradiation effects on ZrC have been released and fundamental aspects of defect evolution and kinetics are not well understood although some atomistic simulations and phenomenological studies have been performed. This work was carried out to understand the damage evolution in float-zone refined ZrC with different stoichiometries. Proton irradiations at 800 ?C up to doses of 3 dpa were performed on ZrCx (where x ranges from 0.9 to 1.2) to investigate the damage evolution. The irradiation-induced defects, such as density of dislocation loops, at different stoichiometries and doses which were characterized by transmission electron microscopy (TEM) is presented and discussed.

Y. Huang; B.R. Maier; T.R. Allen

2014-10-01T23:59:59.000Z

271

Creep effects in diffusion bonding of oxygen-free copper  

E-Print Network [OSTI]

Diffusion is the transport of atoms or particles through the surrounding material. Various microstructural changes in metals are based on the diffusion phenomena. In solid metals the diffusion is closely related to crystallographic defects. In single-component metals the dominant mechanism of diffusion is the vacancy mechanism. Diffusion bonding is a direct technological application of diffusion. It is an advanced solidstate joining process in which the surfaces of two components are brought to contact with each other and heated under a pressing load in a controlled environment. During the process, the contact surfaces are bonded by atomic diffusion across the interface and as a result, one solid piece is formed. The condition of high temperature and low applied stress combined with relatively long process duration enables the creep effects to take place in bonded metals. Furthermore, creep causes unwanted permanent deformations in the bonded components. Some authors suggest that there could be a threshold fo...

Moilanen, Antti

272

Evolution of the nanostructure OF VVER-1000 RPV materials under neutron irradiation and post irradiation annealing  

SciTech Connect (OSTI)

A high nickel VVER-1000 (15Kh2NMFAA) base metal (1.34 wt% Ni, 0.47% Mn, 0.29% Si and 0.05% Cu), and a high nickel (12Kh2N2MAA) weld metal (1.77 wt% Ni, 0.74% Mn, 0.26% Si and 0.07% Cu) have been characterized by atom probe tomography to determine the changes in the microstructure during neutron irradiation to high fluences. The base metal was studied in the unirradiated condition and after neutron irradiation to fluences between 2.4 and 14.9 x 10{sup 23} m{sup -2} (E > 0.5 MeV), and the weld metal was studied in the unirradiated condition and after neutron irradiation to fluences between 2.4 and 11.5 x 10{sup 23} m{sup -2} (E > 0.5 MeV). High number densities of 2-nm-diameter Ni-, Si- and Mn-enriched nanoclusters were found in the neutron irradiated base and weld metals. No significant copper enrichment was associated with these nanoclusters and no copper-enriched precipitates were observed. The number densities of these nanoclusters correlate with the shifts in the {Delta}T{sub 41 J} ductile-to-brittle transition temperature. These nanoclusters were present after a post irradiOffice of Science (US)C, but had dissolved into the matrix after 24 h at 450 C. Phosphorus, nickel, silicon and to a lesser extent manganese were found to be segregated to the dislocations.

Miller, Michael K [ORNL; Chernobaeva, A. A. [Russian Research Center, Kurchatov Institute, Moscow, Russia; Shtrombakh, Ya. [Russian Research Center, Kurchatov Institute, Moscow, Russia; Erak, D. [Russian Research Center, Kurchatov Institute, Moscow, Russia; Zabusov, Oleg O. [Russian Research Center, Kurchatov Institute, Moscow, Russia; Russell, Kaye F [ORNL; Nanstad, Randy K [ORNL

2009-01-01T23:59:59.000Z

273

The Impact of Thermal Conductivity and Diffusion Rates on Water Vapor Transport through Gas Diffusion Layers  

E-Print Network [OSTI]

Water management in a hydrogen polymer electrolyte membrane (PEM) fuel cell is critical for performance. The impact of thermal conductivity and water vapor diffusion coefficients in a gas diffusion layer (GDL) has been studied by a mathematical model. The fraction of product water that is removed in the vapour phase through the GDL as a function of GDL properties and operating conditions has been calculated and discussed. Furthermore, the current model enables identification of conditions when condensation occurs in each GDL component and calculation of temperature gradient across the interface between different layers, providing insight into the overall mechanism of water transport in a given cell design. Water transport mode and condensation conditions in the GDL components depend on the combination of water vapor diffusion coefficients and thermal conductivities of the GDL components. Different types of GDL and water removal scenarios have been identified and related to experimentally-determined GDL proper...

Burlatsky, S F; Gummallaa, M; Condita, D; Liua, F

2013-01-01T23:59:59.000Z

274

Phase transformations in neutron-irradiated Zircaloys  

SciTech Connect (OSTI)

Microstructural evolution in Zircaloy-2 and -4 spent-fuel cladding specimens after approx.3 years of irradiation in commercial power reactors has been investigated by TEM and HVEM. Two kinds of precipitates induced by the fast-neutron irradiation in the reactors have been identified, i.e., Zr/sub 3/O and cubic-ZrO/sub 2/ particles approximately 2 to 10 nm in size. By means of a weak-beam dark-field ''2-1/2D-microscopy'' technique, the bulk nature of the precipitates and the surficial nature of artifact oxide and hydride phases could be discerned. The Zr(Fe/sub x/,Cr/sub 1-x/)/sub 2/ and Zr/sub 2/(Fe/sub x/,Ni/sub 1-x/) intermetallic precipitates normally present in the as-fabricated material virtually dissolved in the spent-fuel cladding specimens after a fast-neutron fluence of approx.4 x 10/sup 21/ ncm/sup -2/ in the power reactors. The observed radiation-induced phase transformations are compared with predictions based on the currently available understanding of the alloy characteristics. 29 refs.

Chung, H.M.

1986-04-01T23:59:59.000Z

275

A Simplified Shuttle Irradiation Facility for ATR  

SciTech Connect (OSTI)

During the past fifteen years there has been a steady increase in the demand for radioisotopes in nuclear medicine and a corresponding decline in the number of reactors within the U.S. capable of producing them. The Advanced Test Reactor (ATR) is the largest operating test reactor in the U.S., but its isotope production capabilities have been limited by the lack of an installed isotope shuttle irradiation system. A concept for a simple "low cost" shuttle irradiation facility for ATR has been developed. Cost were reduced (in comparison to previous ATR designs) by using a shielded trough of water installed in an occupiable cubicle as a shielding and contamination control barrier for the send and receive station. This shielding concept also allows all control valves to be operated by hand and thus the need for an automatic control system was eliminated. It was determined that 4-5 ft of water would be adequate to shield the isotopes of interest while shuttles are transferred to a small carrier. An additional feature of the current design is a non-isolatable by-pass line, which provides a minimum coolant flow to the test region regardless of which control valves are opened or closed. This by-pass line allows the shuttle facility to be operated without bringing reactor coolant water into the cubicle except for send and receive operations.

A. J. Palmer; S. T. Laflin

1999-08-01T23:59:59.000Z

276

Optimisation of buildings' solar irradiation availability  

SciTech Connect (OSTI)

In order to improve the sustainability of new and existing urban settlements it is desirable to maximise the utilisation of the solar energy incident on the building envelope, whether by passive or active means. To this end we have coupled a multi-objective optimisation algorithm with the backwards ray tracing program RADIANCE which itself uses a cumulative sky model for the computation of incident irradiation (W h/m{sup 2}) in a single simulation. The parameters to optimise are geometric (the height of buildings up to their facade and the height and orientation of roofs), but with the constraint of maintaining an overall built volume, and the objective function is heating season solar irradiation offset by envelope heat losses. This methodology has been applied to a range of urban typologies and produces readily interpretable results. The focus of this work is on the design of new urban forms but the method could equally be applied to examine the relative efficiency of existing urban settlements, by comparison of existing forms with the calculated optima derived from relevant specifications of the building envelope. (author)

Kaempf, Jerome Henri; Montavon, Marylene; Bunyesc, Josep; Robinson, Darren [Solar Energy and Building Physics Laboratory, Station 18, Ecole Polytechnique Federale de Lausanne, 1015 Lausanne (Switzerland); Bolliger, Raffaele [Industrial Energy Systems Laboratory, Station 9, Ecole Polytechnique Federale de Lausanne, 1015 Lausanne (Switzerland)

2010-04-15T23:59:59.000Z

277

LWRS ATR Irradiation Testing Readiness Status  

SciTech Connect (OSTI)

The Light Water Reactor Sustainability (LWRS) Program was established by the U.S. Department of Energy Office of Nuclear Energy (DOE-NE) to develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors. The LWRS Program is divided into four R&D Pathways: (1) Materials Aging and Degradation; (2) Advanced Light Water Reactor Nuclear Fuels; (3) Advanced Instrumentation, Information and Control Systems; and (4) Risk-Informed Safety Margin Characterization. This report describes an irradiation testing readiness analysis in preparation of LWRS experiments for irradiation testing at the Idaho National Laboratory (INL) Advanced Test Reactor (ATR) under Pathway (2). The focus of the Advanced LWR Nuclear Fuels Pathway is to improve the scientific knowledge basis for understanding and predicting fundamental performance of advanced nuclear fuel and cladding in nuclear power plants during both nominal and off-nominal conditions. This information will be applied in the design and development of high-performance, high burn-up fuels with improved safety, cladding integrity, and improved nuclear fuel cycle economics

Kristine Barrett

2012-09-01T23:59:59.000Z

278

Diffusion and impurity segregation in hydrogen-implanted silicon carbide  

SciTech Connect (OSTI)

Diffusion and segregation behavior of hydrogen and oxygen in silicon carbide subjected to H implantation and subsequent annealing were studied with a number of analytical techniques including Secondary Ion Mass Spectrometry (SIMS), Rutherford backscattering spectrometry in channeling geometry, field emission scanning electron microscopy, optical microscopy, cross-sectional transmission electron microscopy, and atomic force microscopy. H{sup +} implantation was carried out with energies of 200?keV, 500?keV, or 1?MeV to doses of 1?×?10{sup 16}, 1?×?10{sup 17}, or 2?×?10{sup 17} ion/cm{sup 2}, and thermal treatment was conducted in flowing argon for 1 to 2 h at temperatures of 740, 780, 1000, or 1100?°C. The process of migration and eventual loss of hydrogen in a point defect regime is postulated to proceed to a large extent through ionized vacancies. This conclusion was derived from the observed substantial difference in H mobilities in n- vs. p-type SiC as the population of ionized vacancies is governed by the Fermi-Dirac statistics, i.e., the position of the Fermi level. For higher doses, a well defined buried planar zone forms in SiC at the maximum of deposited energy, comprising numerous microvoids and platelets that are trapping sites for hydrogen atoms. At a certain temperature, a more or less complete exfoliation of the implanted layer is observed. For a 1?MeV implant heated to 1100?°C in nominally pure argon, SIMS profiling reveals a considerable oxygen peak of 10{sup 16} O atoms/cm{sup 2} situated at a depth close to that of the peak of the implanted H{sup +}. Similarly, 1100?°C annealing of a 200?keV implant induces the formation of a thin oxide (4?nm), located at the interface between the implanted layer and the substrate as evidenced by both SIMS and HRTEM. The measurements were taken on the part of the sample that remained un-exfoliated. In view of a lack of convincing evidence that a hexagonal SiC might contain substantial amounts of oxygen, further investigation is under way to elucidate its presence in the irradiation-damaged films.

Barcz, A., E-mail: barcz@ite.waw.pl [Institute of Electron Technology, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Institute of Physics, Polish Academy of Sciences, 02-668 Warsaw (Poland); Kozubal, M.; Ratajczak, J.; Go?aszewska, K. [Institute of Electron Technology, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Jakie?a, R.; Dyczewski, J.; Wojciechowski, T. [Institute of Physics, Polish Academy of Sciences, 02-668 Warsaw (Poland); Celler, G. K. [Institute for Advanced Materials, Devices, and Nanotechnology (IAMDN)/Department of Materials Science and Engineering, Rutgers University, New Brunswick, New Jersey 08901 (United States)

2014-06-14T23:59:59.000Z

279

Postharvest irradiation treatment effect on grapefruit functional components and their role in prevention of colon cancer  

E-Print Network [OSTI]

and irradiation significantly (P ? 0.05) affected the bioactive compounds in grapefruit, however, the effect of storage was prominent. The third study examined the influence of irradiation and freeze drying on bioactive compounds of grapefruit. Irradiation...

Vanamala, Jairam Krishna Prasad

2005-11-01T23:59:59.000Z

280

Causal Baryon Diffusion and Colored Noise  

E-Print Network [OSTI]

We construct a model of baryon diffusion which has the desired properties of causality and analyticity. The model also has the desired property of colored noise, meaning that the noise correlation function is not a Dirac delta function in space and time; rather, it depends on multiple time and length constants. The model can readily be incorporated in 3+1 dimensional second order viscous hydro-dynamical models of heavy ion collisions, which is particularly important at beam energies where the baryon density is large.

J. I. Kapusta; C. Young

2014-04-18T23:59:59.000Z

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


281

Band Formation during Gaseous Diffusion in Aerogels  

E-Print Network [OSTI]

We study experimentally how gaseous HCl and NH_3 diffuse from opposite sides of and react in silica aerogel rods with porosity of 92 % and average pore size of about 50 nm. The reaction leads to solid NH_4Cl, which is deposited in thin sheet-like structures. We present a numerical study of the phenomenon. Due to the difference in boundary conditions between this system and those usually studied, we find the sheet-like structures in the aerogel to differ significantly from older studies. The influence of random nucleation centers and inhomogeneities in the aerogel is studied numerically.

M. A. Einarsrud; F. A. Maao; A. Hansen; M. Kirkedelen; J. Samseth

1997-06-18T23:59:59.000Z

282

Diffusion for an ensemble of Hamiltonians  

E-Print Network [OSTI]

Two ensembles of standard maps are studied analytically and numerically. In particular the diffusion coefficient is calculated. For one type of ensemble the chaotic parameter is chosen at random from a Gaussian distribution and is then kept fixed, while for the other type it varies from step to step. The effect of averaging out the details is evaluated and in particular it is found to be much more effective in the process of the second type. The work may shed light on the possible properties of different ensembles of mixed systems.

Or Alus; Shmuel Fishman

2014-09-17T23:59:59.000Z

283

ARM - Field Campaign - Diffuse Shortwave IOP  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNGExperience4AJ01)3,Cloud OD SensorgovCampaignsComplex LayeredgovCampaignsDiffuse

284

Carbon Diffusion Across Dissimilar Steel Welds  

E-Print Network [OSTI]

of recrystallised ferrite. The major consequence of carbon diffusion is a loss of strength in the carbon depleted region and an increase in hardness in the carburised region. These zones are immediately adjacent to one another and provide a significant change... , tungsten and niobium, a sequence of alloy carbides may be formed, giving rise to the more complex M23C6 and M6C carbides at higher tempering temperatures. In this notation "M" indicates a mixture of metal atoms. Nutting (1969) summarises the sequence...

Race, Julia Margaret

1992-12-08T23:59:59.000Z

285

SHORT COMMUNICATION Microbeam irradiation of C. elegans nematode in microfluidic  

E-Print Network [OSTI]

SHORT COMMUNICATION Microbeam irradiation of C. elegans nematode in microfluidic channels M implemented a microfluidic tool for microbeam irradiation of Caenorhabditis elegans. The device allows into the microfluidic device through liquid flow between an inlet and an outlet, and the size of each microchannel

Brenner, David Jonathan

286

Retention of Hydrogen Isotopes in Neutron Irradiated Tungsten  

SciTech Connect (OSTI)

To investigate the effects of neutron irradiation on hydrogen isotope retention in tungsten, disk-type specimens of pure tungsten were irradiated in the High Flux Isotope Reactor in Oak Ridge National Laboratory followed by exposure to high flux deuterium (D) plasma in Idaho National Laboratory. The results obtained for low dose n-irradiated specimens (0.025 dpa for tungsten) are reviewed in this paper. Irradiation at coolant temperature of the reactor (around 50 degrees C) resulted in the formation of strong trapping sites for D atoms. The concentrations of D in n-irradiated specimens were ranging from 0.1 to 0.4 mol% after exposure to D plasma at 200 and 500 degrees C and significantly higher than those in non-irradiated specimens because of D-trapping by radiation defects. Deep penetration of D up to a depth of 50-100 µm was observed at 500 degrees C. Release of D in subsequent thermal desorption measurements continued up to 900 degrees C. These results were compared with the behaviour of D in ion-irradiated tungsten, and distinctive features of n-irradiation were discussed.

Yuji Hatano; Masashi Shimada; Yasuhisa Oya; Guoping Cao; Makoto Kobayashi; Masanori Hara; Brad J. Merrill; Kenji Okuno; Mikhail A. Sokolov; Yutai Katoh

2013-03-01T23:59:59.000Z

287

Irradiation effects in high-density polyethylene Jussi Polvia  

E-Print Network [OSTI]

Irradiation effects in high-density polyethylene Jussi Polvia , Kai Nordlunda a simulations, we have studied the irradiation effects in high density polyethylene. We determined the threshold energy for creating defects in the polyethylene lattice as a function of the incident angle. We found

Nordlund, Kai

288

Asymmetric Orientational Writing in glass with femtosecond laser irradiation  

E-Print Network [OSTI]

Asymmetric Orientational Writing in glass with femtosecond laser irradiation B. Poumellec,1 M in the dielectric inducing an asymmetric stress field is proposed. ©2013 Optical Society of America OCIS codes: (160. Prade, and A. Mysyrowicz, "Femtosecond laser irradiation stress induced in pure silica," Opt. Express 11

Boyer, Edmond

289

Physica B 308310 (2001) 612615 Irradiation effects in semiconducting diamonds  

E-Print Network [OSTI]

Physica B 308­310 (2001) 612­615 Irradiation effects in semiconducting diamonds N. Kristianpoller irradiation on semiconducting diamonds (type IIb) were studied and compared with those induced at the same conditions in natural (type Ia) and in synthetic diamonds. Methods of optical absorption, of X-ray and light

Chen, Reuven

290

SPECTRAL SOLAR IRRADIANCE AND ITS ENTROPIC EFFECT ON EARTH'S CLIMATE  

E-Print Network [OSTI]

SPECTRAL SOLAR IRRADIANCE AND ITS ENTROPIC EFFECT ON EARTH'S CLIMATE Wei Wu1 , Yangang Liu1 of the spectral solar irradiance (SSI) at the top of the Earth's atmosphere by the Solar Radiation and Climate's entropy flux from the TOA incident solar radiation. Two extreme cases are examined by using Planck

291

ASCA Discovery of Diffuse 6.4 keV Emission Near the Sgr C Complex: A New X-ray Reflection Nebula  

E-Print Network [OSTI]

We present an ASCA discovery of diffuse hard X-ray emission from the Sgr C complex with its peak in the vicinity of the molecular cloud core. The X-ray spectrum is characterized by a strong 6.4-keV line and large absorption. These properties suggest that Sgr C is a new X-ray reflection nebula which emits fluorescent and scattered X-rays via irradiation from an external X-ray source. We found no adequately bright source in the immediate Sgr C vicinity to fully account for the fluorescence. The irradiating source may be the Galactic nucleus Sgr A*, which was brighter in the past than it is now as is suggested from observations of the first X-ray reflection nebula Sgr B2.

H. Murakami; K. Koyama; M. Tsujimoto; Y. Maeda; M. Sakano

2000-12-14T23:59:59.000Z

292

Standard Guide for Packaging Materials for Foods to Be Irradiated  

E-Print Network [OSTI]

1.1 This guide provides a format to assist producers and users of food packaging materials in selecting materials that have the desirable characteristics for their intended use and comply with applicable standards or government authorizations. It outlines parameters that should be considered when selecting food-contact packaging materials intended for use during irradiation of prepackaged foods and it examines the criteria for fitness for their use. 1.2 This guide identifies known regulations and regulatory frameworks worldwide pertaining to packaging materials for holding foods during irradiation; but it does not address all regulatory issues associated with the selection and use of packaging materials for foods to be irradiated. It is the responsibility of the user of this guide to determine the pertinent regulatory issues in each country where foods are to be irradiated and where irradiated foods are distributed. 1.3 This guide does not address all of the food safety issues associated with the synergisti...

American Society for Testing and Materials. Philadelphia

2009-01-01T23:59:59.000Z

293

Chemical oxygen diffusion coefficient measurement by conductivity relaxation--correlation between tracer diffusion  

E-Print Network [OSTI]

Chemical oxygen diffusion coefficient measurement by conductivity relaxation--correlation between J. P., Grenier J. C., Loup J. P. ABSTRACT Chemical oxygen diusion coecient ÂŻ(D)was measured the oxygen partial pressure in the surrounding atmosphere of the sample. The consequent evolution

Paris-Sud XI, Université de

294

Low cost fuel cell diffusion layer configured for optimized anode water management  

DOE Patents [OSTI]

A fuel cell comprises a cathode gas diffusion layer, a cathode catalyst layer, an anode gas diffusion layer, an anode catalyst layer and an electrolyte. The diffusion resistance of the anode gas diffusion layer when operated with anode fuel is higher than the diffusion resistance of the cathode gas diffusion layer. The anode gas diffusion layer may comprise filler particles having in-plane platelet geometries and be made of lower cost materials and manufacturing processes than currently available commercial carbon fiber substrates. The diffusion resistance difference between the anode gas diffusion layer and the cathode gas diffusion layer may allow for passive water balance control.

Owejan, Jon P; Nicotera, Paul D; Mench, Matthew M; Evans, Robert E

2013-08-27T23:59:59.000Z

295

Overview of SIMS-Based Experimental Studies of Tracer Diffusion in Solids and Application to Mg Self-Diffusion  

SciTech Connect (OSTI)

Tracer diffusivities provide the most fundamental information on diffusion in materials and are the foundation of robust diffusion databases. Compared to traditional radiotracer techniques that utilize radioactive isotopes, the secondary ion mass spectrometry (SIMS) based thin-film technique for tracer diffusion is based on the use of enriched stable isotopes that can be accurately profiled using SIMS. Experimental procedures & techniques that are utilized for the measurement of tracer diffusion coefficients are presented for pure magnesium, which presents some unique challenges due to the ease of oxidation. The development of a modified Shewmon-Rhines diffusion capsule for annealing Mg and an ultra-high vacuum (UHV) system for sputter deposition of Mg isotopes are discussed. Optimized conditions for accurate SIMS depth profiling in polycrystalline Mg are provided. An automated procedure for the correction of heat-up and cool-down times during tracer diffusion annealing is discussed. The non-linear fitting of a SIMS depth profile data using the thin film Gaussian solution to obtain the tracer diffusivity along with the background tracer concentration and tracer film thickness is discussed. An Arrhenius fit of the Mg self-diffusion data obtained using the low-temperature SIMS measurements from this study and the high-temperature radiotracer measurements of Shewmon and Rhines (1954) was found to be a good representation of both types of diffusion data that cover a broad range of temperatures between 250 - 627 C (523 900 K).

Kulkarni, Nagraj S [ORNL; Warmack, Robert J Bruce [ORNL; Radhakrishnan, Balasubramaniam [ORNL; HunterJr., Jerry [Virginia Polytechnic Institute and State University; Sohn, Yong Ho [University of Central Florida; Coffey, Kevin [University of Central Florida; Murch, Prof. Graeme [University of Newcastle, NSW, Australia; Belova, Irina [University of Newcastle, NSW, Australia

2014-01-01T23:59:59.000Z

296

Reaction and diffusion in turbulent combustion  

SciTech Connect (OSTI)

The motivation for this project is the need to obtain a better quantitative understanding of the technologically-important phenomenon of turbulent combustion. In nearly all applications in which fuel is burned-for example, fossil-fuel power plants, furnaces, gas-turbines and internal-combustion engines-the combustion takes place in a turbulent flow. Designers continually demand more quantitative information about this phenomenon-in the form of turbulent combustion models-so that they can design equipment with increased efficiency and decreased environmental impact. For some time the PI has been developing a class of turbulent combustion models known as PDF methods. These methods have the important virtue that both convection and reaction can be treated without turbulence-modelling assumptions. However, a mixing model is required to account for the effects of molecular diffusion. Currently, the available mixing models are known to have some significant defects. The major motivation of the project is to seek a better understanding of molecular diffusion in turbulent reactive flows, and hence to develop a better mixing model.

Pope, S.B. [Mechanical and Aerospace Engineering, Ithaca, NY (United States)

1993-12-01T23:59:59.000Z

297

Commercial Building Partnerships Replication and Diffusion  

SciTech Connect (OSTI)

This study presents findings from survey and interview data investigating replication efforts of Commercial Building Partnership (CBP) partners that worked directly with the Pacific Northwest National Laboratory (PNNL). PNNL partnered directly with 12 organizations on new and retrofit construction projects, which represented approximately 28 percent of the entire U.S. Department of Energy (DOE) CBP program. Through a feedback survey mechanism, along with personal interviews, PNNL gathered quantitative and qualitative data relating to replication efforts by each organization. These data were analyzed to provide insight into two primary research areas: 1) CBP partners’ replication efforts of technologies and approaches used in the CBP project to the rest of the organization’s building portfolio (including replication verification), and, 2) the market potential for technology diffusion into the total U.S. commercial building stock, as a direct result of the CBP program. The first area of this research focused specifically on replication efforts underway or planned by each CBP program participant. Factors that impact replication include motivation, organizational structure and objectives firms have for implementation of energy efficient technologies. Comparing these factors between different CBP partners revealed patterns in motivation for constructing energy efficient buildings, along with better insight into market trends for green building practices. The second area of this research develops a diffusion of innovations model to analyze potential broad market impacts of the CBP program on the commercial building industry in the United States.

Antonopoulos, Chrissi A.; Dillon, Heather E.; Baechler, Michael C.

2013-09-16T23:59:59.000Z

298

Distributed Wind Diffusion Model Overview (Presentation)  

SciTech Connect (OSTI)

Distributed wind market demand is driven by current and future wind price and performance, along with several non-price market factors like financing terms, retail electricity rates and rate structures, future wind incentives, and others. We developed a new distributed wind technology diffusion model for the contiguous United States that combines hourly wind speed data at 200m resolution with high resolution electricity load data for various consumer segments (e.g., residential, commercial, industrial), electricity rates and rate structures for utility service territories, incentive data, and high resolution tree cover. The model first calculates the economics of distributed wind at high spatial resolution for each market segment, and then uses a Bass diffusion framework to estimate the evolution of market demand over time. The model provides a fundamental new tool for characterizing how distributed wind market potential could be impacted by a range of future conditions, such as electricity price escalations, improvements in wind generator performance and installed cost, and new financing structures. This paper describes model methodology and presents sample results for distributed wind market potential in the contiguous U.S. through 2050.

Preus, R.; Drury, E.; Sigrin, B.; Gleason, M.

2014-07-01T23:59:59.000Z

299

Diffusion in biofilms respiring on electrodes  

SciTech Connect (OSTI)

The goal of this study was to measure spatially and temporally resolved effective diffusion coefficients (De) in biofilms respiring on electrodes. Two model electrochemically active biofilms, Geobacter sulfurreducens PCA and Shewanella oneidensis MR-1, were investigated. A novel nuclear magnetic resonance microimaging perfusion probe capable of simultaneous electrochemical and pulsed-field gradient nuclear magnetic resonance (PFG-NMR) techniques was used. PFG-NMR allowed for noninvasive, nondestructive, high spatial resolution in situ De measurements in living biofilms respiring on electrodes. The electrodes were polarized so that they would act as the sole terminal electron acceptor for microbial metabolism. We present our results as both two-dimensional De heat maps and surface-averaged relative effective diffusion coefficient (Drs) depth profiles. We found that (1) Drs decreases with depth in G. sulfurreducens biofilms, following a sigmoid shape; (2) Drs at a given location decreases with G. sulfurreducens biofilm age; (3) average De and Drs profiles in G. sulfurreducens biofilms are lower than those in S. oneidensis biofilms—the G. sulfurreducens biofilms studied here were on average 10 times denser than the S. oneidensis biofilms; and (4) halting the respiration of a G. sulfurreducens biofilm decreases the De values. Density, reflected by De, plays a major role in the extracellular electron transfer strategies of electrochemically active biofilms.

Renslow, Ryan S.; Babauta, Jerome T.; Majors, Paul D.; Beyenal, Haluk

2013-02-15T23:59:59.000Z

300

E-Print Network 3.0 - accelerated partial-breast irradiation...  

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

irradiated for one hour... 1 Irradiation of Nd-Fe-B Permanent Magnets with APS Bending Magnet ... Source: Kemner, Ken - Biosciences Division, Argonne National Laboratory...

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


301

Narrow groove welding gas diffuser assembly and welding torch  

DOE Patents [OSTI]

A diffuser assembly is provided for narrow groove welding using an automatic gas tungsten arc welding torch. The diffuser assembly includes a manifold adapted for adjustable mounting on the welding torch which is received in a central opening in the manifold. Laterally extending manifold sections communicate with a shield gas inlet such that shield gas supplied to the inlet passes to gas passages of the manifold sections. First and second tapered diffusers are respectively connected to the manifold sections in fluid communication with the gas passages thereof. The diffusers extend downwardly along the torch electrode on opposite sides thereof so as to release shield gas along the length of the electrode and at the distal tip of the electrode. The diffusers are of a transverse width which is on the order of the thickness of the electrode so that the diffusers can, in use, be inserted into a narrow welding groove before and after the electrode in the direction of the weld operation.

Rooney, Stephen J. (East Berne, NY)

2001-01-01T23:59:59.000Z

302

Non-Fickian ionic diffusion across high-concentration gradients  

SciTech Connect (OSTI)

A non-Fickian physico-chemical model for electrolyte transport in high-ionic strength systems is developed and tested with laboratory experiments with copper sulfate as an example electrolyte. The new model is based on irreversible thermodynamics and uses measured mutual diffusion coefficients, varying with concentration. Compared to a traditional Fickian model, the new model predicts less diffusion and asymmetric diffusion profiles. Laboratory experiments show diffusion rates even smaller than those predicted by our non-Fickian model, suggesting that there are additional, unaccounted for processes retarding diffusion. Ionic diffusion rates maybe a limiting factor in transporting salts whose effect on fluid density will in turn significantly affect the flow regime. These findings have important implications for understanding and predicting solute transport in geologic settings where dense, saline solutions occur. 30 refs., 5 figs.

Carey, A.E.; Wheatcraft, S.W. [Univ. of Nevada, Reno, NV (United States)] [Univ. of Nevada, Reno, NV (United States); Glass, R.J. [Sandia National Laboratory, Albuquerque, NM (United States)] [and others] [Sandia National Laboratory, Albuquerque, NM (United States); and others

1995-09-01T23:59:59.000Z

303

Instrumentation to Enhance Advanced Test Reactor Irradiations  

SciTech Connect (OSTI)

The Department of Energy (DOE) designated the Advanced Test Reactor (ATR) as a National Scientific User Facility (NSUF) in April 2007 to support U.S. leadership in nuclear science and technology. By attracting new research users - universities, laboratories, and industry - the ATR will support basic and applied nuclear research and development, further advancing the nation's energy security needs. A key component of the ATR NSUF effort is to prove new in-pile instrumentation techniques that are capable of providing real-time measurements of key parameters during irradiation. To address this need, an assessment of instrumentation available and under-development at other test reactors has been completed. Based on this review, recommendations are made with respect to what instrumentation is needed at the ATR and a strategy has been developed for obtaining these sensors. Progress toward implementing this strategy is reported in this document. It is anticipated that this report will be updated on an annual basis.

J. L. Rempe; D. L. Knudson; K. G. Condie; J. E. Daw; S. C. Taylor

2009-09-01T23:59:59.000Z

304

Irradiation behavior of metallic fast reactor fuels  

SciTech Connect (OSTI)

Metallic fuels were the first fuels chosen for liquid metal cooled fast reactors (LMR's). In the late 1960's world-wide interest turned toward ceramic LMR fuels before the full potential of metallic fuel was realized. However, during the 1970's the performance limitations of metallic fuel were resolved in order to achieve a high plant factor at the Argonne National Laboratory's Experimental Breeder Reactor II. The 1980's spawned renewed interest in metallic fuel when the Integral Fast Reactor (IFR) concept emerged at Argonne National Laboratory. A fuel performance demonstration program was put into place to obtain the data needed for the eventual licensing of metallic fuel. This paper will summarize the results of the irradiation program carried out since 1985.

Pahl, R.G.; Porter, D.L.; Crawford, D.C.; Walters, L.C.

1991-01-01T23:59:59.000Z

305

Optimization parameter design for proton irradiation accelerator  

E-Print Network [OSTI]

The proton irradiation accelerator is widely founded for industry application, and should be designed as compact, reliable, and easy operate. A 10 MeV proton beam is designed to be injected into the slow circulation ring with the repetition rate of 0.5 Hz for accumulation and acceleration, and then the beam with the energy of 300MeV will be slowly extracted by third order resonance method. For getting a higher intensity and more uniform beam, the height of the injection bump is carefully optimised during the injection period. Besides, in order to make the extracted beam with a more uniform distribution, a RF Knock-out method is adopted, and the RF kicker's amplitude is well optimised.

Yu-Wen An; Hong-Fei Ji; Sheng Wang; Shou-Yan Xu

2014-11-20T23:59:59.000Z

306

Recovery of niobium from irradiated targets  

DOE Patents [OSTI]

A process for selective separation of niobium from proton irradiated molybdenum targets is provided and includes dissolving the molybdenum target in a hydrogen peroxide solution to form a first ion-containing solution, contacting the first ion-containing solution with a cationic resin whereby ions selected form the group consisting of molybdenum, biobium, technetium, selenium, vanadium, arsenic, germanium, zirconium and rubidium remain in a second ion-containing solution while ions selected from the group consisting of rubidium, zinc, beryllium, cobalt, iron, manganese, chromium, strontium, yttrium and zirconium are selectively adsorbed by the cationic resin; adjusting the pH of the second ion-containing solution to within a range of from about 5.0 to about 6.0; contacting the pH adjusting second ion-containing solution with a dextran-based material for a time to selectively separate niobium from the solution and recovering the niobium from the dextran-based material.

Phillips, Dennis R. (Los Alamos, NM); Jamriska, Sr., David J. (Los Alamos, NM); Hamilton, Virginia T. (Los Alamos, NM)

1994-01-01T23:59:59.000Z

307

AGC-3 Irradiation Data Qualification Final Report  

SciTech Connect (OSTI)

The Graphite Technology Development Program will run a series of six experiments to quantify the effects of irradiation on nuclear grade graphite. The third experiment, Advanced Graphite Creep 3 (AGC 3), began with Advanced Test Reactor (ATR) Cycle 152B on November 27, 2012, and ended with ATR Cycle 155B on April 23, 2014. This report documents qualification of AGC 3 experiment irradiation monitoring data for use by the Very High Temperature Reactor (VHTR) Technology Development Office (TDO) Program for research and development activities required to design and license the first VHTR nuclear plant. Qualified data meet the requirements for data collection and use as described in the experiment planning and quality assurance documents. Failed data do not meet the requirements. Trend data may not meet the requirements, but may still provide some useable information. All thermocouples (TCs) functioned throughout the AGC 3 experiment. There was one interval between December 18, 2012, and December 20, 2012, where 10 NULL values were reported for various TCs. These NULL values were deleted from the Nuclear Data Management and Analysis System database. All temperature data are Qualified for use by the VHTR TDO Program. Argon, helium, and total gas flow data were within expected ranges and are Qualified for use by the VHTR TDO Program. Total gas flow was approximately 50 sccm through the AGC 3 experiment capsule. Helium gas flow was briefly increased to 100 sccm during ATR shutdowns. At the start of the AGC 3 experiment, moisture in the outflow gas line was stuck at a constant value of 335.6174 ppmv for the first cycle (Cycle 152B). When the AGC 3 experiment capsule was reinstalled in ATR for Cycle 154B, a new moisture filter was installed. Moisture data from Cycle 152B are Failed. All moisture data from the final three cycles (Cycles 154B, 155A, and 155B) are Qualified for use by the VHTR TDO Program.

Laurence Hull

2014-08-01T23:59:59.000Z

308

Lattice Boltzmann computations for reaction-diffusion equations  

SciTech Connect (OSTI)

A lattice Boltzmann model for reaction-diffusion systems is developed. The method provides an efficient computational scheme for simulating a variety of problems described by the reaction-diffusion equations. Diffusion phenomena, the decay to a limit cycle, and the formation of Turing patterns are studied. The results of lattice Boltzmann calculations are compared with the lattice gas method and with theoretical predictions, showing quantitative agreement. The model is extended to include velocity convection in chemically reacting fluid flows.

Ponce Dawson, S.; Chen, S.; Doolen, G.D. (Center for Nonlinear Studies and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States))

1993-01-15T23:59:59.000Z

309

18.366 Random Walks and Diffusion, Spring 2005  

E-Print Network [OSTI]

Discrete and continuum modeling of diffusion processes in physics, chemistry, and economics. Topics include central limit theorems, continuous-time random walks, Levy flights, correlations, extreme events, mixing, ...

Bazant, Martin Z.

310

Optical waveguides in SBN by zinc vapor diffusion  

E-Print Network [OSTI]

at 600'C for a 12. 5 i1m Wide 1000'C Zinc Vapor Diffused SBN:60 Waveguide Measured at X = 0. 81 pm. IV. SBN:60 Amplitude Modulator Results . . . . . V. SBN:60 Mach-Zehnder Interferometer Results. . . . VI. Voltage-Length Product Comparison...: (a) extraordinary (TM), (b) 1. 5 x ordinary (TE). 12. Surface damage on SBN:60 diffused at 1000'C with an SiOz diffusion mask. 13. Zinc in-diffusion in SBN:60 25 . . . . . 26 . . . . . 27 . . . . . 28 29 14. Barium out-diffuison in SBN:60...

Quinn, Jeffrey Dale

1991-01-01T23:59:59.000Z

311

Diffusion coefficient of three-dimensional Yukawa liquids  

SciTech Connect (OSTI)

The purpose of this work is an investigation of the diffusion coefficient of the dust component in complex plasma. The computer simulation of the Yukawa liquids was made on the basis of the Langevin equation, which takes into account the influence of buffer plasma on the dust particles dynamics. The Green–Kubo relation was used to calculate the diffusion coefficient. Calculations of the diffusion coefficient for a wide range of the system parameters were performed. Using obtained numerical data, we constructed the interpolation formula for the diffusion coefficient. We also show that the interpolation formula correctly describes experimental data obtained under microgravity conditions.

Dzhumagulova, K. N.; Ramazanov, T. S.; Masheeva, R. U. [IETP, Al Farabi Kazakh National University, 71, al Farabi ave., Almaty 050040 (Kazakhstan)] [IETP, Al Farabi Kazakh National University, 71, al Farabi ave., Almaty 050040 (Kazakhstan)

2013-11-15T23:59:59.000Z

312

Probabilistic Bisimulations of Switching and Resetting Diffusions Alessandro Abate  

E-Print Network [OSTI]

Probabilistic Bisimulations of Switching and Resetting Diffusions Alessandro Abate Delft Center for Systems and Control, TU Delft, The Netherlands a.abate@tudelft.nl Abstract-- This contribution presents

Abate, Alessandro

313

Using Rare Gas Permeation to Probe Methanol Diffusion near the...  

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

at temperatures just above the glass transition. The diffusivity near the glass transition is characterized by an activation energy and prefactor that are seven and 1030...

314

Uranium and Strontium Batch Sorption and Diffusion Kinetics into...  

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

Uranium and Strontium Batch Sorption and Diffusion Kinetics into Mesoporous Silica Friday, February 27, 2015 Figure 1 Figure 1. Transmission electron microscopy images of (A)...

315

Optical processing furnace with quartz muffle and diffuser plate  

DOE Patents [OSTI]

An optical furnace for annealing a process wafer comprising a source of optical energy, a quartz muffle having a door to hold the wafer for processing, and a quartz diffuser plate to diffuse the light impinging on the quartz muffle; a feedback system with a light sensor located in the door or wall of the muffle is also provided for controlling the source of optical energy. The quartz for the diffuser plate is surface etched (to give the quartz diffusive qualities) in the furnace during a high intensity burn-in process.

Sopori, Bhushan L. (Denver, CO)

1995-01-01T23:59:59.000Z

316

aerospace knowledge diffusion: Topics by E-print Network  

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

to codify: Implications for the knowledge - based economy" Prometheus 19 Richards, Debbie 15 Inverse diffusion from knowledge of power densities Guillaume Bal Mathematics...

317

adrenal diffuse large: Topics by E-print Network  

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

diffusion is the effect of geometry, including the localization of aftershocks on a fractal fault network and the impact of extended rupture lengths which control the typical...

318

Orientation Visit to the Portsmouth Gaseous Diffusion Plant  

Office of Environmental Management (EM)

Analysis (DSA) and Technical Safety Requirements (TSR) for Portsmouth Gaseous Diffusion Plant Category 2 Non-leased Facilities: X-345 Special Nuclear Material Storage Facility;...

319

Nanocrystalline SiC and Ti3SiC2 Alloys for Reactor Materials: Diffusion of Fission Product Surrogates  

SciTech Connect (OSTI)

MAX phases, such as titanium silicon carbide (Ti3SiC2), have a unique combination of both metallic and ceramic properties, which make them attractive for potential nuclear applications. Ti3SiC2 has been suggested in the literature as a possible fuel cladding material. Prior to the application, it is necessary to investigate diffusivities of fission products in the ternary compound at elevated temperatures. This study attempts to obtain relevant data and make an initial assessment for Ti3SiC2. Ion implantation was used to introduce fission product surrogates (Ag and Cs) and a noble metal (Au) in Ti3SiC2, SiC, and a dual-phase nanocomposite of Ti3SiC2/SiC synthesized at PNNL. Thermal annealing and in-situ Rutherford backscattering spectrometry (RBS) were employed to study the diffusivity of the various implanted species in the materials. In-situ RBS study of Ti3SiC2 implanted with Au ions at various temperatures was also performed. The experimental results indicate that the implanted Ag in SiC is immobile up to the highest temperature (1273 K) applied in this study; in contrast, significant out-diffusion of both Ag and Au in MAX phase Ti3SiC2 occurs during ion implantation at 873 K. Cs in Ti3SiC2 is found to diffuse during post-irradiation annealing at 973 K, and noticeable Cs release from the sample is observed. This study may suggest caution in using Ti3SiC2 as a fuel cladding material for advanced nuclear reactors operating at very high temperatures. Further studies of the related materials are recommended.

Henager, Charles H.; Jiang, Weilin

2014-11-01T23:59:59.000Z

320

Mapping the geographical diffusion of new words  

E-Print Network [OSTI]

Language in social media is rich with linguistic innovations, most strikingly in the new words and spellings that constantly enter the lexicon. Despite assertions about the power of social media to connect people across the world, we find that many of these neologisms are restricted to geographically compact areas. Even for words that become ubiquituous, their growth in popularity is often geographical, spreading from city to city. Thus, social media text offers a unique opportunity to study the diffusion of lexical change. In this paper, we show how an autoregressive model of word frequencies in social media can be used to induce a network of linguistic influence between American cities. By comparing the induced network with the geographical and demographic characteristics of each city, we can measure the factors that drive the spread of lexical innovation.

Eisenstein, Jacob; Smith, Noah A; Xing, Eric P

2012-01-01T23:59:59.000Z

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


321

Turbulent diffusion with rotation or magnetic fields  

E-Print Network [OSTI]

The turbulent diffusion tensor describing the evolution of the mean concentration of a passive scalar is investigated for forced turbulence either in the presence of rotation or a magnetic field. With rotation the Coriolis force causes a sideways deflection of the flux of mean concentration. Within the magnetohydrodynamics approximation there is no analogous effect from the magnetic field because the effects on the flow do not depend on the sign of the field. Both rotation and magnetic fields tend to suppress turbulent transport, but this suppression is weaker in the direction along the magnetic field. Turbulent transport along the rotation axis is not strongly affected by rotation, except on shorter length scales, i.e. when the scale of the variation of the mean field becomes comparable with the scale of the energy-carrying eddied.

Brandenburg, Axel; Vasil, Geoffrey M

2009-01-01T23:59:59.000Z

322

Diffusion of irreversible energy technologies under uncertainty  

SciTech Connect (OSTI)

This paper presents a model of technology diffusion is consistent with characteristics of participants in most energy markets. Whereas the models used most widely for empirical research are based on the assumption that the extended delays in adoption of cost-saving innovations are the result of either lack of knowledge about the new processes or heterogeneity across potential adopters, the model presented in this paper is based on the strategic behavior by firms. The strategic interdependence of the firms` decisions is rooted in spillover effects associated with an inability to exclude others from the learning-by-doing acquired when a firm implements a new technology. The model makes extensive use of recent developments in investment theory as it relates irreversible investments under uncertainty.

Cacallo, J.D.; Sutherland, R.J.

1993-09-01T23:59:59.000Z

323

Diffuse gamma-rays from galactic halos  

E-Print Network [OSTI]

Here we review our current knowledge on diffuse gamma-rays from galactic halos. Estimates of the relative contribution of the various emission processes at low and high latitudes are compared to the data over 6 decades in energy. The observed spectral shape differs from what was expected, especially at ver low and very high energies. In the latter case, above 1 GeV, the sky emission related to gas exceeds the expected pi^0 decay spectrum. At energies below 1 MeV the relatively high gamma-ray intensity indicates at high density of nearly relativistic electrons which would have a strong influence on the energy and ionisation balance of the interstellar medium. Given the EGRET results for the Magellanic Clouds the gamma-ray emissivity in the outer halo is probably small, so that a substantial amount of baryonic dark matter may be hidden at 20-50 kpc radius without inducing observable gamma-ray emission.

M. Pohl

1996-03-12T23:59:59.000Z

324

Indoor and Outdoor Spectroradiometer Intercomparison for Spectral Irradiance Measurement  

SciTech Connect (OSTI)

This report details the global spectral irradiance intercomparison using spectroradiometers that was organized by the National Renewable Energy Laboratory's Solar Radiation Research Laboratory. The intercomparison was performed both indoors and outdoors on September 17, 2013. Five laboratories participated in the intercomparison using 10 spectroradiometers, and a coordinated measurement setup and a common platform were employed to compare spectral irradiances under both indoor and outdoor conditions. The intercomparison aimed to understand the performance of the different spectroradiometers and to share knowledge in making spectral irradiance measurements. This intercomparison was the first of its kind in the United States.

Habte, A.; Andreas, A.; Ottoson, L.; Gueymard, C.; Fedor, G.; Fowler, S.; Peterson, J.; Naranen, R.; Kobashi, T.; Akiyama, A.; Takagi, S.

2014-05-01T23:59:59.000Z

325

Gamma irradiation effects on the biodegradation of lignin  

E-Print Network [OSTI]

parts: biological utilization of irradiated Calcium Lignosulphonate (CLS) and irradiation effects on the composition of CLS. The CLS used in this study was a commercially available lignin compound which is produced by flash evaporation of spent... 4/ X / 2. 0 3. 0 4. 0 5. 0 6. 0 7. 0 Wavelength in microns 8. 0 9. 0 28 CHAPTER VI RESULTS AND CONCLUSIONS A commercia I CLS was irradiated in a dry state to various total dose levels of Co-60 gamma rays. The effects on the structure...

Krysinski, Thomas Leon

1966-01-01T23:59:59.000Z

326

Electron Beam Irradiation for Improving Safety of Fruits and Vegetables  

E-Print Network [OSTI]

. An alternative may be irradiation which is emerging as a promising tool to enhance safety and extend shelf life of fresh and fresh cut produce. Gamma rays have been the most extensively studied form of irradiation and have been successfully applied to spices..., tubers, grains and meat products for the space program. However, consumer reluctance has limited its application over a broad range of food stuffs. As a result, alternate irradiation technologies such as e-beam and X-rays are attracting attention...

Adavi, Megha Sarthak

2012-07-16T23:59:59.000Z

327

A Simplified HTTR Diffusion Theory Benchmark  

SciTech Connect (OSTI)

The Georgia Institute of Technology (GA-Tech) recently developed a transport theory benchmark based closely on the geometry and the features of the HTTR reactor that is operational in Japan. Though simplified, the benchmark retains all the principal physical features of the reactor and thus provides a realistic and challenging test for the codes. The purpose of this paper is twofold. The first goal is an extension of the benchmark to diffusion theory applications by generating the additional data not provided in the GA-Tech prior work. The second goal is to use the benchmark on the HEXPEDITE code available to the INL. The HEXPEDITE code is a Green’s function-based neutron diffusion code in 3D hexagonal-z geometry. The results showed that the HEXPEDITE code accurately reproduces the effective multiplication factor of the reference HELIOS solution. A secondary, but no less important, conclusion is that in the testing against actual HTTR data of a full sequence of codes that would include HEXPEDITE, in the apportioning of inevitable discrepancies between experiment and models, the portion of error attributable to HEXPEDITE would be expected to be modest. If large discrepancies are observed, they would have to be explained by errors in the data fed into HEXPEDITE. Results based on a fully realistic model of the HTTR reactor are presented in a companion paper. The suite of codes used in that paper also includes HEXPEDITE. The results shown here should help that effort in the decision making process for refining the modeling steps in the full sequence of codes.

Rodolfo M. Ferrer; Abderrafi M. Ougouag; Farzad Rahnema

2010-10-01T23:59:59.000Z

328

Pyrolytic carbon free-radical evolution and irradiation damage of polyimide under low-energy proton irradiation  

SciTech Connect (OSTI)

Ionization and displacement effects are basic phenomena in damage processes of materials under space-particle irradiation. In this paper, the damage behaviors were investigated on the polyimide under proton irradiation using electron paramagnetic resonance (EPR) spectra analysis and optical absorbance valuation. The results indicate that the proton irradiation induces the formation of pyrolytic carbon free-radical with a g value of 2.0025, and the population of free radicals increases with the irradiation fluence. The most important finding is that the irradiation-induced free-radical population increases linearly with the displacement damage dose, as does the optical degradation, whereas the ionization effect alone, during the irradiation, cannot induce the formation of pyrolytic carbon free radical. Furthermore, during the post storage, after irradiation, the free-radical population decreases following a sum of an exponential and a linear mode with the storage time. It is interesting that, during the post storage, the recovery of the degraded optical absorbance of the polyimide follows a similar mode to that of free radicals, and the characteristic time constant changes with the wavelength of the optical spectra.

Sun Chengyue; Wu Yiyong; Xiao Jingdong; Li Ruifeng; Yang Dezhuang; He Shiyu [National Key Lab in Materials Behaviors and Evaluation Technology in Space Environments, Harbin Institute of Technology, Harbin 150001 (China)

2011-12-15T23:59:59.000Z

329

AGC-2 Irradiation Data Qualification Final Report  

SciTech Connect (OSTI)

The Graphite Technology Development Program will run a series of six experiments to quantify the effects of irradiation on nuclear grade graphite. The second Advanced Graphite Creep (AGC) experiment (AGC-2) began with Advanced Test Reactor (ATR) Cycle 149A on April 12, 2011, and ended with ATR Cycle 151B on May 5, 2012. The purpose of this report is to qualify AGC-2 irradiation monitoring data following INL Management and Control Procedure 2691, Data Qualification. Data that are Qualified meet the requirements for data collection and use as described in the experiment planning and quality assurance documents. Data that do not meet the requirements are Failed. Some data may not quite meet the requirements, but may still provide some useable information. These data are labeled as Trend. No Trend data were identified for the AGC-2 experiment. All thermocouples functioned throughout the AGC-2 experiment. There was one instance where spurious signals or instrument power interruption resulted in a recorded temperature value being well outside physical reality. This value was identified and labeled as Failed data. All other temperature data are Qualified. All helium and argon gas flow data are within expected ranges. Total gas flow was approximately 50 sccm through the capsule. Helium gas flow was briefly increased to 100 sccm during reactor shutdown. All gas flow data are Qualified. At the start of the experiment, moisture in the outflow gas line increased to 200 ppmv then declined to less than 10 ppmv over a period of 5 days. This increase in moisture coincides with the initial heating of the experiment and drying of the system. Moisture slightly exceeded 10 ppmv three other times during the experiment. While these moisture values exceed the 10 ppmv threshold value, the reported measurements are considered accurate and to reflect moisture conditions in the capsule. All moisture data are Qualified. Graphite creep specimens are subjected to one of three loads, 393 lbf, 491 lbf, or 589 lbf. Loads were consistently within 5% of the specified values throughout the experiment. Stack displacement increased consistently throughout the experiment with total displacement ranging from 1 to 1.5 inches. No anomalous values were identified. During reactor outages, a set of pneumatic rams are used to raise the stacks of graphite creep specimens to ensure the specimens have not become stuck within the test train. This stack raising was performed after all cycles when the capsule was in the reactor. All stacks were raised successfully after each cycle. The load and displacement data are Qualified

Laurence C. Hull

2012-07-01T23:59:59.000Z

330

Convergence Speed of GARCH Option Price to Diffusion Option Price  

E-Print Network [OSTI]

Convergence Speed of GARCH Option Price to Diffusion Option Price Jin-Chuan Duan, Yazhen Wang that as the time interval between two consecutive observations shrinks to zero, a properly constructed GARCH model will weakly converge to a bivariate diffusion. Naturally the European option price under the GARCH model

Chaudhuri, Sanjay

331

Electro-diffusion in a plasma with two ion species  

SciTech Connect (OSTI)

Electric field is a thermodynamic force that can drive collisional inter-ion-species transport in a multicomponent plasma. In an inertial confinement fusion capsule, such transport causes fuel ion separation even with a target initially prepared to have equal number densities for the two fuel ion species. Unlike the baro-diffusion driven by ion pressure gradient and the thermo-diffusion driven by ion and electron temperature gradients, electro-diffusion has a critical dependence on the charge-to-mass ratio of the ion species. Specifically, it is shown here that electro-diffusion vanishes if the ion species have the same charge-to-mass ratio. An explicit expression for the electro-diffusion ratio is obtained and used to investigate the relative importance of electro- and baro-diffusion mechanisms. In particular, it is found that electro-diffusion reinforces baro-diffusion in the deuterium and tritium mix, but tends to cancel it in the deuterium and helium-3 mix.

Kagan, Grigory; Tang Xianzhu [Theoretical Division Los Alamos National Laboratory Los Alamos, New Mexico 87545 (United States)

2012-08-15T23:59:59.000Z

332

ENERGY DIFFUSION IN HARMONIC SYSTEM WITH CONSERVATIVE NOISE  

E-Print Network [OSTI]

systems or lattice dimension d 3, where the thermal diffusivity is finite. 1. Introduction Lattice the evolution of the energy and identify the thermal diffusivity. In the harmonic chain with noise this agrees to what it is expected for deterministic anharmonic dynamics. In this article we consider the same

Paris-Sud XI, Université de

333

Optical processing furnace with quartz muffle and diffuser plate  

DOE Patents [OSTI]

An optical furnace for annealing a process wafer comprising a source of optical energy, a quartz muffle having a door to hold the wafer for processing, and a quartz diffuser plate to diffuse the light impinging on the quartz muffle; a feedback system with a light sensor located in the wall of the muffle is also provided for controlling the source of optical energy.

Sopori, Bhushan L. (Denver, CO)

1996-01-01T23:59:59.000Z

334

Experimental determination of the boundary condition for diffuse photons  

E-Print Network [OSTI]

of a turbid medium, the light transport is described by the diffusion approxima- tion of the radiative of a turbid medium within a few transport mean free paths, the diffusion equation is no longer satisfied light transport through a turbid (i.e., highly scatter- ing) medium and in imaging objects

Zhu, Xiangdong

335

Beta Advection-Diffusion Model Columbia Basin Research  

E-Print Network [OSTI]

Beta Advection-Diffusion Model Jim Norris Columbia Basin Research University of Washington Box Model (SSM) is loosely called a Beta Advection-Diffusion model. The SSM estimates a single parameter this single parameter characterized fish migration. The purpose of this note is to define the Beta Advection

Washington at Seattle, University of

336

DIFFUSION MECHANISMS FOR MULTIMEDIA BROADCASTING IN MOBILE AD HOC NETWORKS  

E-Print Network [OSTI]

DIFFUSION MECHANISMS FOR MULTIMEDIA BROADCASTING IN MOBILE AD HOC NETWORKS E. Baccelli Hitachi HSAL: Philippe.Jacquet@inria.fr ABSTRACT Scarce bandwidth and interferences in mobile ad-hoc networks yield in view to gain enough performance and allow applications such as multimedia diffusion in an ad hoc

Paris-Sud XI, Université de

337

Peer Effects in the Diffusion of Solar Photovoltaic Panels  

E-Print Network [OSTI]

Peer Effects in the Diffusion of Solar Photovoltaic Panels Bryan Bollinger NYU Stern School base of consumers in the reference group. We study the diffusion of solar photovoltaic panels of an environmentally beneficial technology, solar photovoltaic (PV) panels. Policymakers are particularly interested

Lee, Daeyeol

338

Uniformly Accurate Diffusive Relaxation Schemes for Multiscale Transport Equations  

E-Print Network [OSTI]

, radiative transfer, and transport equations for waves in random media, have a diffusive scaling that leads #12; 1. Introduction Many transport equations, such as the neutron transport [CZ], radiative transferUniformly Accurate Diffusive Relaxation Schemes for Multiscale Transport Equations Shi JIN y

339

Diffusion MRI of Complex Tissue Structure David Solomon Tuch  

E-Print Network [OSTI]

Diffusion MRI of Complex Tissue Structure by David Solomon Tuch B.A., Physics, University Solomon Tuch Submitted to the Division of Health Sciences and Technology on January 11, 2002, in partial to be beyond the scope of diffusion imaging methodology. Thesis Supervisor: Van Jay Wedeen Title: Associate

Duncan, James S.

340

Modeling of Spectralon diffusers for radiometric calibration in remote sensing  

E-Print Network [OSTI]

function (BRDF) of the diffuser outside the measured calibration set, or a model of the degradation, and anisotropy of the scattering. We also describe the result of modeling the degradation of a Spectralon diffuser after deposi- tion, under UV radiation, of a silicone layer. © 2003 Society of Photo

Sprik, Rudolf

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


341

Slippery diffusion-limited aggregation Clair R. Seager1,  

E-Print Network [OSTI]

can translationally diffuse over the surface of the other. By contrast, shear-rigid bonding createsSlippery diffusion-limited aggregation Clair R. Seager1, * and Thomas G. Mason2, 1 Department attractions in liquids form irreversible "slippery" bonds that are not shear-rigid. Through event

Weeks, Eric R.

342

MULTISCALE MODELING OF DIFFUSION-INDUCED DEFORMATION PROCESSES  

E-Print Network [OSTI]

MULTISCALE MODELING OF DIFFUSION- INDUCED DEFORMATION PROCESSES Dr. Eugene Olevsky Friday, February 19, 2010 Engineering Bldg. Room E 300 Sintering is a high temperature process of bonding together of matter transport by different diffusion mechanisms driven by the high surface energy of aggregates

Ponce, V. Miguel

343

Diffusion with dissolution and precipitation in a porous media  

E-Print Network [OSTI]

Diffusion with dissolution and precipitation in a porous media approximation by a finite volume. Quelques tests numériques sont ensuite montrés. KEYWORDS: diffusion, dissolution­precipitation, porous­ ficiency of such disposals relies on material barriers. For such a use, cement concrete offers

Herbin, Raphaèle

344

Diffusion with dissolution and precipitation in a porous media  

E-Print Network [OSTI]

Diffusion with dissolution and precipitation in a porous media approximation by a finite volume numériques sont ensuite montrés. KEYWORDS: diffusion, dissolution-precipitation, porous media, finite volumes barriers. For such a use, cement concrete offers the advantage of having a weak porosity. However, disposal

Herbin, Raphaèle

345

Uranium and cesium diffusion in fuel cladding of electrogenerating channel  

SciTech Connect (OSTI)

The results of reactor tests of a carbonitride fuel in a single-crystal cladding from a molybdenum-based alloy can be used in substantiating the operational reliability of fuels in developing a project of a megawatt space nuclear power plant. The results of experimental studies of uranium and cesium penetration into the single-crystal cladding of fuel elements with a carbonitride fuel are interpreted. Those fuel elements passed nuclear power tests in the Ya-82 pilot plant for 8300 h at a temperature of about 1500°C. It is shown that the diffusion coefficients for uranium diffusion into the cladding are virtually coincident with the diffusion coefficients measured earlier for uranium diffusion into polycrystalline molybdenum. It is found that the penetration of uranium into the cladding is likely to occur only in the case of a direct contact between the cladding and fuel. The experimentally observed nonmonotonic uranium-concentration profiles are explained in terms of predominant uranium diffusion along grain boundaries. It is shown that a substantially nonmonotonic behavior observed in our experiment for the uranium-concentration profile may be explained by the presence of a polycrystalline structure of the cladding in the surface region from its inner side. The diffusion coefficient is estimated for the grain-boundary diffusion of uranium. The diffusion coefficients for cesium are estimated on the basis of experimental data obtained in the present study.

Vasil’ev, I. V., E-mail: fnti@mail.ru; Ivanov, A. S.; Churin, V. A. [National Research Center Kurchatov Institute (Russian Federation)

2014-12-15T23:59:59.000Z

346

Vacancy mediated substitutional diffusion in binary crystalline solids  

E-Print Network [OSTI]

Vacancy mediated substitutional diffusion in binary crystalline solids Anton Van der Ven a,*, Hui coefficients of substi- tutional alloys from first principles. The focus is restricted to vacancy mediated and grain boundaries that can act as vacancy sources) and diffusion in a solid containing a continuous

Ceder, Gerbrand

347

Thermal diffusivity mapping of 4D carbon-carbon composites  

SciTech Connect (OSTI)

High resolution, 2-D thermal diffusivity maps of carbon-carbon composites were obtained by a state-of-the-art infrared thermal imaging system. Unlike the traditional single-point IR detector used for thermal diffusivity measurements, the IR camera is capable of capturing images in its 256 x 256 pixel Focal Plane Array detector in a snap-shot mode. The camera takes up to 200 images at a rate of 120 frames/second. The temperature resolution of the Ir camera is 0.015 C and the spatial resolution is 20 {micro}m. Thermal diffusivity was calculated for each pixel. Four-direction carbon-carbon composites were used for the thermal diffusivity mapping study. The fiber bundles along the heat flow direction were found to have 25% higher diffusivity values than the surrounding matrix. The diffusivity map also showed detailed local variations in diffusivity which were impossible to measure using a single-point detector. Accurate diffusivity maps are very important to the design of composite materials.

Wang, H.; Dinwiddie, R.B.

1997-03-01T23:59:59.000Z

348

The modelling of irradiation-enhanced phosphorus segregation in neutron irradiated reactor pressure vessel submerged-arc welds  

SciTech Connect (OSTI)

Recent results on neutron-irradiated RPV submerged-arc welds have revealed grain boundary segregation of phosphorus during irradiation, which may lead to intergranular fracture. However, the experimental database is insufficient to define the dependence of the process on variables such ad dose, dose-rate and temperature. This paper describes work in which two existing models of phosphorus segregation, under thermal or irradiation conditions, have been developed to obtain predictions of these dependencies. The critical parameters in the models have been adjusted to give consistency with the available reference data, and predictions have been made of the dependence of segregation on a number of variables.

Druce, S.G.; English, C.A.; Foreman, A.J.E.; McElroy, R.J.; Vatter, I.A. [AEA Technology, Didcot (United Kingdom). Harwell Lab.; Bolton, C.J.; Buswell, J.T.; Jones, R.B. [Nuclear Electric, Berkeley (United Kingdom). Berkeley Technology Centre

1996-12-31T23:59:59.000Z

349

Solar irradiance forecasting at multiple time horizons and novel methods to evaluate uncertainty  

E-Print Network [OSTI]

Solar irradiance data . . . . . . . . . . . . .Accuracy . . . . . . . . . . . . . . . . . Solar Resourcev Uncertainty In Solar Resource: Forecasting

Marquez, Ricardo

2012-01-01T23:59:59.000Z

350

K.K. Gan ATLAS Tracker Upgrade Workshop 1 Irradiation Results and Transmission on  

E-Print Network [OSTI]

Power vs Dosage all VCSELs still produce optical power at SLHC dosage should irradiate at lower Workshop 14 Post-Irradiation Analysis all arrays except ULM 5 G still produce optical power post-irradiationK.K. Gan ATLAS Tracker Upgrade Workshop 1 Irradiation Results and Transmission on Small Cables

Gan, K. K.

351

Irradiation behavior of the interaction product of U-Mo fuel particle dispersion in an Al matrix.  

SciTech Connect (OSTI)

Irradiation performance of U-Mo fuel particles dispersed in Al matrix is stable in terms of fuel swelling and is suitable for the conversion of research and test reactors from highly enriched uranium (HEU) to low enriched uranium (LEU). However, tests of the fuel at high temperatures and high burnups revealed obstacles caused by the interaction layers forming between the fuel particle and matrix. In some cases, fission gas filled pores grow and interconnect in the interdiffusion layer resulting in fuel plate failure. Postirradiation observations are made to examine the behavior of the interdiffusion layers. The interdiffusion layers show a fluid-like behavior characteristic of amorphous materials. In the amorphous interdiffusion layers, fission gas diffusivity is high and the material viscosity is low so that the fission gas pores readily form and grow. Based on the observations, a pore formation mechanism is proposed and potential remedies to suppress the pore growth are also introduced.

Kim, Y.S.; Hofman, G. (Nuclear Engineering Division)

2012-06-01T23:59:59.000Z

352

NREL Solar Radiation Research Laboratory (SRRL): Baseline Measurement System (BMS); Golden, Colorado (Data)  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The SRRL was established at the Solar Energy Research Institute (now NREL) in 1981 to provide continuous measurements of the solar resources, outdoor calibrations of pyranometers and pyrheliometers, and to characterize commercially available instrumentation. The SRRL is an outdoor laboratory located on South Table Mountain, a mesa providing excellent solar access throughout the year, overlooking Denver. Beginning with the basic measurements of global horizontal irradiance, direct normal irradiance and diffuse horizontal irradiance at 5-minute intervals, the SRRL Baseline Measurement System now produces more than 130 data elements at 1-min intervals that are available from the Measurement & Instrumentation Data Center Web site. Data sources include global horizontal, direct normal, diffuse horizontal (from shadowband and tracking disk), global on tilted surfaces, reflected solar irradiance, ultraviolet, infrared (upwelling and downwelling), photometric and spectral radiometers, sky imagery, and surface meteorological conditions (temperature, relative humidity, barometric pressure, precipitation, snow cover, wind speed and direction at multiple levels). Data quality control and assessment include daily instrument maintenance (M-F) with automated data quality control based on real-time examinations of redundant instrumentation and internal consistency checks using NREL's SERI-QC methodology. Operators are notified of equipment problems by automatic e-mail messages generated by the data acquisition and processing system. Radiometers are recalibrated at least annually with reference instruments traceable to the World Radiometric Reference (WRR).

Stoffel, T.; Andreas, A.

353

agr-1 irradiation experiment: Topics by E-print Network  

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

E. Schwartz Department Direct-normal solar irradiance (DNSI), the total energy in the solar spectrum incident in unit time Schwartz, Stephen E. 13 An Experiment at HiRadMat:...

354

Review of Dynamic Recovery Effects on Ion Irradiation Damage...  

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

6H–SiC, ionization processes are less dominant. Citation: Weber WJ, Y Zhang, and LM Wang.2012."Review of Dynamic Recovery Effects on Ion Irradiation Damage in...

355

Materials for cold neutron sources: Cryogenic and irradiation effects  

SciTech Connect (OSTI)

Materials for the construction of cold neutron sources must satisfy a range of demands. The cryogenic temperature and irradiation create a severe environment. Candidate materials are identified and existing cold sources are briefly surveyed to determine which materials may be used. Aluminum- and magnesium-based alloys are the preferred materials. Existing data for the effects of cryogenic temperature and near-ambient irradiation on the mechanical properties of these alloys are briefly reviewed, and the very limited information on the effects of cryogenic irradiation are outlined. Generating mechanical property data under cold source operating conditions is a daunting prospect. It is clear that the cold source material will be degraded by neutron irradiation, and so the cold source must be designed as a brittle vessel. The continued effective operation of many different cold sources at a number of reactors makes it clear that this can be accomplished. 46 refs., 8 figs., 2 tab.

Alexander, D.J.

1990-01-01T23:59:59.000Z

356

Irradiation facilities at the Los Alamos Meson Physics Facility  

SciTech Connect (OSTI)

The irradiation facilities for testing SSC components and detector systems are described. Very high intensity proton, neutron, and pion fluxes are available with beam kinetic energies of up to 800 MeV. 4 refs., 12 figs., 2 tabs.

Sandberg, V.

1990-01-01T23:59:59.000Z

357

Sandis irradiator for dried sewage solids. Final safety analysis report  

SciTech Connect (OSTI)

Analyses of the hazards associated with the operation of the Sandia irradiator for dried sewage solids, as well as methods and design considerations to minimize these hazards, are presented in accordance with DOE directives.

Morris, M.

1980-07-01T23:59:59.000Z

358

Microstructural and Mechanical Property Changes in Ion Irradiated Tunsgten  

E-Print Network [OSTI]

on the sustainability of tungsten as a plasma facing material (PFM). During operation, PFM must withstand harsh conditions with combined effects from high temperature, mechanical stress, irradiation, transmutation, and the production of hydrogen (H) and helium (He...

General, Michael

2013-04-08T23:59:59.000Z

359

Post-irradiation Examination and Fission Product Inventory Analysis of AGR-1 Irradiation Capsules  

SciTech Connect (OSTI)

The AGR-1 experiment was the first in a series of Advanced Gas Reactor (AGR) experiments designed to test TRISO fuel under High Temperature Gas Reactor irradiation conditions. This experiment was irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) and is currently undergoing post-irradiation examination (PIE) at INL’s Materials and Fuels Complex (MFC). The inventory and distribution of fission products, especially Ag-110m, was assessed and analyzed for all the components of the AGR-1 capsules. This data should help inform the study of fission product migration in coated particle fuel. Gamma spectrometry was used to measure the activity of various different fission products in the different components of the AGR-1 test train. Each capsule contained: 12 fuel compacts, a graphite holder that kept the fuel compacts in place, graphite spacers that were above and below the graphite holders and fuel compacts, gas lines through which a helium neon gas mixture flowed in and out of each capsule, and the stainless steel shell that contained the experiment. Gamma spectrometry results and the experimental techniques used to capture these results will be presented for all the capsule components. The components were assayed to determine the total activity of different fission products present in or on them. These totals are compared to the total expected activity of a particular fission product in the capsule based on predictions from physics simulation. Based on this metric, a significant fraction of the Ag-110m was detected outside the fuel compacts, but the amount varied highly between the 6 capsules. Very small fractions of Cs-137 (<2E-5), Cs-134 (<1e-5), and Eu-154 (<4e-4) were detected outside of the fuel compacts. Additionally, the distribution of select fission products in some of the components including the fuel compacts and the graphite holders were measured and will be discussed.

J M Harp; P D Demkowicz; S A Ploger

2012-10-01T23:59:59.000Z

360

Irradiation Assisted Grain Boundary Segregation in Steels  

SciTech Connect (OSTI)

The understanding of radiation-induced grain boundary segregation (RIS) has considerably improved over the past decade. New models have been introduced and much effort has been devoted to obtaining comprehensive information on segregation from the literature. Analytical techniques have also improved so that chemical analysis of layers 1 nm thick is almost routine. This invited paper will review the major methods used currently for RIS prediction: namely, Rate Theory, Inverse Kirkendall, and Solute Drag approaches. A summary is made of the available data on phosphorus RIS in reactor pressure vessel (RPV) steels. This will be discussed in the light of the predictions of the various models in an effort to show which models are the most reliable and easy to use for forecasting P segregation behaviour in steels. A consequence of RIS in RPV steels is a radiation induced shift in the ductile to brittle transition temperature (DBTT). It will be shown how it is possible to relate radiation-induced P segregation levels to DBTT shift. Examples of this exercise will be given for RPV steels and for ferritic steels being considered for first wall fusion applications. Cr RIS in high alloy stainless steels and associated irradiation-assisted stress corrosion cracking (IASCC) will be briefly discussed. (authors)

Lu, Zheng; Faulkner, Roy G. [IPTME, Loughborough University, Loughborough, Leics (United Kingdom)

2008-07-01T23:59:59.000Z

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


361

Recovery of germanium-68 from irradiated targets  

DOE Patents [OSTI]

A process for selective separation of germanium-68 from proton irradiated molybdenum targets is provided and includes dissolving the molybdenum target in a hydrogen peroxide solution to form a first ion-containing solution, contacting the first ion-containing solution with a cationic resin whereby ions selected from the group consisting of molybdenum, niobium, technetium, selenium, vanadium, arsenic, germanium, zirconium and rubidium remain in a second ion-containing solution while ions selected from the group consisting of rubidium, zinc, beryllium, cobalt, iron, manganese, chromium, strontium, yttrium and zirconium are selectively adsorbed by the first resin, adjusting the pH of the second ion-containing solution to within a range of from about 0.7 to about 3.0, adjusting the soluble metal halide concentration in the second ion-containing solution to a level adapted for subsequent separation of germanium, contacting the pH-adjusted, soluble metal halide-containing second ion-containing solution with a dextran-based material whereby germanium ions are separated by the dextran-based material, and recovering the germanium from the dextran-based material, preferably by distillation.

Phillips, Dennis R. (Los Alamos, NM); Jamriska, Sr., David J. (Los Alamos, NM); Hamilton, Virginia T. (Los Alamos, NM)

1993-01-01T23:59:59.000Z

362

Ion irradiation induced effects in polyamidoimide  

SciTech Connect (OSTI)

The interaction between ion beam and polyamidoimide (PAI) is studied by means of low-temperature infrared spectroscopy. 200 keV Ar{sup +} and 250 keV He{sup +} beams with fluences ranging from 10{sup 13} ions cm{sup {minus}2} to 5{times}10{sup 16} ions cm{sup {minus}2} are found to induce atomic bond breaks leading to absorption bands at 2344, 2261, and 2125 cm{sup {minus}1} corresponding respectively to CO{sub 2}, C=N=N and C=N--R vibrations. Shrinkage of the polymer along with a drastic decrease of the resistivity during Ar{sup +} and He{sup +} irradiation are observed. Speculations on the respective role of electronic processes and atomic collisions in the evolution of the polymer are made. No evidence of PAI modification through knock-on mechanism for fluences lower than 5{times}10{sup 15} ions cm{sup {minus}2} is noticed. In fact, our results would suggest a predominant role of the electronic processes for the low fluences (up to 5{times}10{sup 15} ions cm{sup {minus}2} ), whereas a degradation mechanism based on atomic collisions is more likely to take place for higher fluences. A theoretical mechanism of reactions based upon our Fourier transform infrared (FTIR) and secondary ion mass spectroscopies (SIMS) results, describing the chemical changes occurring in the PAI, is presented and briefly discussed.

Merhari, L.; Belorgeot, C.; Moliton, J.P. (Laboratoire d'Electronique des Polymeres sous Faisceaux Ioniques 123, avenue Albert Thomas, 87060 Limoges Cedex (France))

1991-09-01T23:59:59.000Z

363

Use of laser extensometer for mechanical test on irradiated materials  

SciTech Connect (OSTI)

Techniques have been developed by EDF`s hot laboratory in Chinon for performing mechanical tests on irradiated materials. Some of these techniques aim to facilitate strain measurements, which are particularly difficult to perform on irradiated specimens at high temperatures or on subsize specimens. Recent progress has been driven by laser technology combined with software development. The use of this technique, which allows strain measurements without contact on the specimen, is described for tensile (especially on subsize specimens), fatigue and creep tests.

Brillaud, C.; Meylogan, T.; Salathe, P. [Electricite de France, Avoine (France)

1996-12-31T23:59:59.000Z

364

Phase-field Model for Interstitial Loop Growth Kinetics and Thermodynamic and Kinetic Models of Irradiated Fe-Cr Alloys  

SciTech Connect (OSTI)

Microstructure evolution kinetics in irradiated materials has strongly spatial correlation. For example, void and second phases prefer to nucleate and grow at pre-existing defects such as dislocations, grain boundaries, and cracks. Inhomogeneous microstructure evolution results in inhomogeneity of microstructure and thermo-mechanical properties. Therefore, the simulation capability for predicting three dimensional (3-D) microstructure evolution kinetics and its subsequent impact on material properties and performance is crucial for scientific design of advanced nuclear materials and optimal operation conditions in order to reduce uncertainty in operational and safety margins. Very recently the meso-scale phase-field (PF) method has been used to predict gas bubble evolution, void swelling, void lattice formation and void migration in irradiated materials,. Although most results of phase-field simulations are qualitative due to the lake of accurate thermodynamic and kinetic properties of defects, possible missing of important kinetic properties and processes, and the capability of current codes and computers for large time and length scale modeling, the simulations demonstrate that PF method is a promising simulation tool for predicting 3-D heterogeneous microstructure and property evolution, and providing microstructure evolution kinetics for higher scale level simulations of microstructure and property evolution such as mean field methods. This report consists of two parts. In part I, we will present a new phase-field model for predicting interstitial loop growth kinetics in irradiated materials. The effect of defect (vacancy/interstitial) generation, diffusion and recombination, sink strength, long-range elastic interaction, inhomogeneous and anisotropic mobility on microstructure evolution kinetics is taken into account in the model. The model is used to study the effect of elastic interaction on interstitial loop growth kinetics, the interstitial flux, and sink strength of interstitial loop for interstitials. In part II, we present a generic phase field model and discuss the thermodynamic and kinetic properties in phase-field models including the reaction kinetics of radiation defects and local free energy of irradiated materials. In particular, a two-sublattice thermodynamic model is suggested to describe the local free energy of alloys with irradiated defects. Fe-Cr alloy is taken as an example to explain the required thermodynamic and kinetic properties for quantitative phase-field modeling. Finally the great challenges in phase-field modeling will be discussed.

Li, Yulan; Hu, Shenyang Y.; Sun, Xin; Khaleel, Mohammad A.

2011-06-15T23:59:59.000Z

365

Effects of carbon on phosphorus diffusion in SiGe:C and the implications on phosphorus diffusion mechanisms  

SciTech Connect (OSTI)

The use of carbon (C) in SiGe base layers is an important approach to control the base layer dopant phosphorus (P) diffusion and thus enhance PNP heterojunction bipolar transistor (HBT) performance. This work quantitatively investigated the carbon impacts on P diffusion in Si{sub 0.82}Ge{sub 0.18}:C and Si:C under rapid thermal anneal conditions. The carbon molar fraction is up to 0.32%. The results showed that the carbon retardation effect on P diffusion is less effective for Si{sub 0.82}Ge{sub 0.18}:C than for Si:C. In Si{sub 0.82}Ge{sub 0.18}:C, there is an optimum carbon content at around 0.05% to 0.1%, beyond which more carbon incorporation does not retard P diffusion any more. This behavior is different from the P diffusion behavior in Si:C and the B in Si:C and low Ge SiGe:C, which can be explained by the decreased interstitial-mediated diffusion fraction f{sub I}{sup P,?SiGe} to 95% as Ge content increases to 18%. Empirical models were established to calculate the time-averaged point defect concentrations and effective diffusivities as a function of carbon and was shown to agree with previous studies on boron, phosphorus, arsenic and antimony diffusion with carbon.

Lin, Yiheng; Xia, Guangrui [Department of Materials Engineering, The University of British Columbia, 309-6350 Stores Rd, Vancouver, British Columbia V6T 1Z4 (Canada); Yasuda, Hiroshi; Wise, Rick [Texas Instruments, 13121 TI Blvd., Dallas, Texas 75243 (United States); Schiekofer, Manfred; Benna, Bernhard [Texas Instruments Deutschland GmbH, Haggertystrasse 1, 85356 Freising (Germany)

2014-10-14T23:59:59.000Z

366

Oxygen self-diffusion ``fast-paths'' in titanite single crystals and a general method for deconvolving self-diffusion  

E-Print Network [OSTI]

Oxygen self-diffusion ``fast-paths'' in titanite single crystals and a general method most other minerals, titanite rarely if ever forms perfect crystals. In addition to the point defects could occur. During the course of an experimental study of oxygen lattice diffusion in titanite, we

Watson, E. Bruce

367

USE OF SILICON CARBIDE MONITORS IN ATR IRRADIATION TESTING  

SciTech Connect (OSTI)

In April 2007, the Department of Energy (DOE) designated the Advanced Test Reactor (ATR) a National Scientific User Facility (NSUF) to advance US leadership in nuclear science and technology. By attracting new users from universities, laboratories, and industry, the ATR will support basic and applied nuclear research and development and help address the nation's energy security needs. In support of this new program, the Idaho National Laboratory (INL) has developed in-house capabilities to fabricate, test, and qualify new and enhanced temperature sensors for irradiation testing. Although most efforts emphasize sensors capable of providing real-time data, selected tasks have been completed to enhance sensors provided in irradiation locations where instrumentation leads cannot be included, such as drop-in capsule and Hydraulic Shuttle Irradiation System (HSIS) or 'rabbit' locations. For example, silicon carbide (SiC) monitors are now available to detect peak irradiation temperatures between 200°C and 800°C. Using a resistance measurement approach, specialized equipment installed at INL's High Temperature Test Laboratory (HTTL) and specialized procedures were developed to ensure that accurate peak irradiation temperature measurements are inferred from SiC monitors irradiated at the ATR. Comparison examinations were completed by INL to demonstrate this capability, and several programs currently rely on SiC monitors for peak temperature detection. This paper discusses the use of SiC monitors at the ATR, the process used to evaluate them at the HTTL, and presents representative measurements taken using SiC monitors.

K. L. Davis; B. Chase; T. Unruh; D. Knudson; J. L. Rempe

2012-07-01T23:59:59.000Z

368

Impurity Diffusion Coefficients of Al and Zn in Mg Determined from Solid-to-Solid Diffusion Couples  

SciTech Connect (OSTI)

Increasing use and development of lightweight Mgalloys have led to the desire for more fundamental research in and understanding of Mg-based systems. As property enhancing components, Al and Zn are two of the most important and common alloying elements for Mg-alloys. We have investigated the concentration dependent interdiffusion of Al and Zn in Mg using diffusion couples of pure polycrystalline Mg mated to Mg solid solutions containing either <9 at.% Al or <3 at.% Zn. Concentration profiles were determined by electron micro-probe microanalysis of the diffusion zone. The interdiffusion coefficients were determined by the classical Boltzmann-Matano method within the Mg solid solution. As the concentration of Al or Zn approaches the dilute ends, we employ an analytical approach based on the Hall method to estimate the impurity diffusion coefficients. Results of Al and Zn impurity diffusion in Mg are reported and compared to published impurity diffusion coefficients typically determined by thin film techniques.

Kammerer, Catherine [University of Central Florida, Orlando; Kulkarni, Nagraj S [ORNL; Warmack, Robert J Bruce [ORNL; Perry, Kelly A [ORNL; Belova, Irina [University of Newcastle, NSW, Australia; Murch, Prof. Graeme [University of Newcastle, NSW, Australia; Sohn, Yong Ho [University of Central Florida

2013-08-01T23:59:59.000Z

369

Understanding the Regional Variability of Eddy Diffusivity in the Pacific Sector of the Southern Ocean  

E-Print Network [OSTI]

A diagnostic framework is presented, based on the Nakamura effective diffusivity, to investigate the regional variation in eddy diffusivity. Comparison of three different diffusivity calculations enables the effects of ...

Shuckburgh, Emily

370

Spectral Components Analysis of Diffuse Emission Processes  

SciTech Connect (OSTI)

We develop a novel method to separate the components of a diffuse emission process based on an association with the energy spectra. Most of the existing methods use some information about the spatial distribution of components, e.g., closeness to an external template, independence of components etc., in order to separate them. In this paper we propose a method where one puts conditions on the spectra only. The advantages of our method are: 1) it is internal: the maps of the components are constructed as combinations of data in different energy bins, 2) the components may be correlated among each other, 3) the method is semi-blind: in many cases, it is sufficient to assume a functional form of the spectra and determine the parameters from a maximization of a likelihood function. As an example, we derive the CMB map and the foreground maps for seven yeas of WMAP data. In an Appendix, we present a generalization of the method, where one can also add a number of external templates.

Malyshev, Dmitry; /KIPAC, Menlo Park

2012-09-14T23:59:59.000Z

371

Diffuse interstellar bands in M33  

E-Print Network [OSTI]

We present the first sample of diffuse interstellar bands (DIBs) in the nearby galaxy M33. Studying DIBs in other galaxies allows the behaviour of the carriers to be examined under interstellar conditions which can be quite different from those of the Milky Way, and to determine which DIB properties can be used as reliable probes of extragalactic interstellar media. Multi-object spectroscopy of 43 stars in M33 has been performed using Keck/DEIMOS. The stellar spectral types were determined and combined with literature photometry to determine the M33 reddenings E(B-V)_M33. Equivalent widths or upper limits have been measured for the {\\lambda}5780 DIB towards each star. DIBs were detected towards 20 stars, demonstrating that their carriers are abundant in M33. The relationship with reddening is found to be at the upper end of the range observed in the Milky Way. The line of sight towards one star has an unusually strong ratio of DIB equivalent width to E(B-V)_M33, and a total of seven DIBs were detected towards...

Smith, Keith T; Evans, Christopher J; Cox, Nick L J; Sarre, Peter J

2013-01-01T23:59:59.000Z

372

AMBIPOLAR DIFFUSION HEATING IN TURBULENT SYSTEMS  

SciTech Connect (OSTI)

The temperature of the gas in molecular clouds is a key determinant of the characteristic mass of star formation. Ambipolar diffusion (AD) is considered one of the most important heating mechanisms in weakly ionized molecular clouds. In this work, we study the AD heating rate using two-fluid turbulence simulations and compare it with the overall heating rate due to turbulent dissipation. We find that for observed molecular clouds, which typically have Alfven Mach numbers of {approx}1 and AD Reynolds numbers of {approx}20, about 70% of the total turbulent dissipation is in the form of AD heating. AD has an important effect on the length scale where energy is dissipated: when AD heating is strong, most of the energy in the cascade is removed by ion-neutral drift, with a comparatively small amount of energy making it down to small scales. We derive a relation for the AD heating rate that describes the results of our simulations to within a factor of two. Turbulent dissipation, including AD heating, is generally less important than cosmic-ray heating in molecular clouds, although there is substantial scatter in both.

Li, Pak Shing [Astronomy Department, University of California, Berkeley, CA 94720 (United States); Myers, Andrew [Physics Department, University of California, Berkeley, CA 94720 (United States); McKee, Christopher F., E-mail: psli@astron.berkeley.edu, E-mail: atmyers@berkeley.edu, E-mail: cmckee@berkeley.edu [Physics Department and Astronomy Department, University of California, Berkeley, CA 94720 (United States)

2012-11-20T23:59:59.000Z

373

The Hidden Geometry of Attention Diffusion  

E-Print Network [OSTI]

It is difficult to develop quantitative hypotheses to describe the diffusion of information among users, because, in theory, information resources can have an infinite number of copies. And this theoretical possibility has become a reality in an age of information explosion, when a Twitter meme may spread rapidly to millions of users in a few hours. To address this issue, we propose to study the transportation of users' attention between information resources. We use clicks as a proxy of attention and construct attention networks using the browsing log files from 1,000 Web forums. Our previous research discovered the scaling relationship between clicks and users with an exponent $\\theta$ that characterizes the efficiency of forums in spreading information. In this paper we propose a geometric model to explain this scaling property. We view attention networks as $d$-dimensional flow-balls that satisfy $\\theta=(d+1)/d$ and we find that the time-invariant parameter $d$ can be estimated from the spatial distribut...

Wu, Lingfei; Janssen, Marco; Zhang, Jiang; Zhao, Min

2015-01-01T23:59:59.000Z

374

Puzzling Phenomenon of Diffuse Interstellar Bands  

E-Print Network [OSTI]

The discovery of the first diffuse interstellar bands (DIBs) dates back to the pioneering years of stellar spectroscopy. Today, we know about 300 absorption structures of this kind. There exists a great variety of the profiles and intensities of DIBs, so they can not be readily described, classified or characterized. To the present day no reliable identification of the DIBs' carriers has been found. Many carriers of DIBs have been proposed over the years. They ranged from dust grains to free molecules of different kinds, and to more exotic specimens, like hydrogen negative ion. Unfortunately, none of them is responsible for observed DIBs. Furthermore, it was shown that a single carrier cannot be responsible for all known DIBs. It is hard to estimate how many carriers can participate in producing these bands. The problem is further complicated by the fact that to this day it is still impossible to find any laboratory spectrum of any substance which would match the astrophysical spectra. Here, a historical outline concerning DIBs is followed by a brief description of their whole population. Then, a special attention is focused on the procedures trying to extract spectroscopic families within the set of all known DIBs.

B. Wszolek

2007-12-10T23:59:59.000Z

375

Oxygen and nitrogen diffusion in ?-hafnium from first principles  

SciTech Connect (OSTI)

We use a combination of density functional theory and multistate diffusion formalism to analyze the diffusion of oxygen and nitrogen in technologically important hafnium metal. Comparing the local density approximation and the Perdew-Burke-Ernzerhof version of the generalized gradient approximation, we find that a better description of the hafnium lattice in the latter results in the correct sequence of stable and transition states for oxygen interstitials leading to essentially quantitative agreement with experiment. For oxygen diffusion, we find an isotropic temperature-dependent diffusion coefficient of D=0.082e{sup ?2.04/k{sub B}T}cm{sup 2}s{sup ?1} utilizing interstitial sites with hexahedral and octahedral coordination. For the diffusivity of nitrogen, we find that an additional stable interstitial site, the crowdion site, exists and that the diffusion coefficient is D=0.15e{sup ?2.68/k{sub B}T}cm{sup 2}s{sup ?1}. Our results also reproduce the experimental observation that nitrogen diffusivity is lower than that of oxygen in hafnium.

O'Hara, Andrew; Demkov, Alexander A., E-mail: demkov@physics.utexas.edu [Department of Physics, The University of Texas at Austin, Austin, Texas 78712 (United States)

2014-05-26T23:59:59.000Z

376

Effect of elasticity of wall on diffusion in nano channel  

SciTech Connect (OSTI)

Confining walls of nano channel are taken to be elastic to study their effect on the diffusion coefficient of fluid flowing through the channel. The wall is elastic to the extent that it responses to molecular pressure exerted by fluid. The model to study diffusion is based on microscopic considerations. Results obtained for fluid confining to 20 atomic diameter width contrasted with results obtained by considering rigid and smooth wall. The effect of roughness of wall on diffusion can be compensated by the elastic property of wall.

Tankeshwar, K., E-mail: tankesh@pu.ac.in [Computer Centre, Panjab University Chandigarh,- 160014 (India); Srivastava, Sunita [Department of Physics, Panjab University, Chandigarh 160014 (India)

2014-04-24T23:59:59.000Z

377

Energy diffusion in strongly driven quantum chaotic systems  

E-Print Network [OSTI]

The energy evolution of a quantum chaotic system under the perturbation that harmonically depends on time is studied for the case of large perturbation, in which the rate of transition calculated from the Fermi golden rule exceeds the frequency of perturbation. It is shown that the energy evolution retains its diffusive character, with the diffusion coefficient that is asymptotically proportional to the magnitude of perturbation and to the square root of the density of states. The results are supported by numerical calculation. They imply the absence of the quantum-classical correspondence for the energy diffusion and the energy absorption in the classical limit $\\hbar \\to 0$.

P. V. Elyutin

2005-04-14T23:59:59.000Z

378

Bulk diffusion of 1D exclusion process with bond disorder  

E-Print Network [OSTI]

Given a doubly infinite sequence of positive numbers {c_k: k in Z} satisfying a LLN with limit A, we consider the nearest-neighbor simple exclusion process on Z where c_k is the probability rate of jumps between k and k+1. If A is infinite we require an additional minor technical condition. By extending a method developed by K. Nagy, we show that the diffusively rescaled process has hydrodynamic behavior described by the heat equation with diffusion constant 1/A. In particular, the process has diffusive behavior for finite A and subdiffusive behavior for infinite A.

A. Faggionato

2010-03-30T23:59:59.000Z

379

Diffusive mesh relaxation in ALE finite element numerical simulations  

SciTech Connect (OSTI)

The theory for a diffusive mesh relaxation algorithm is developed for use in three-dimensional Arbitary Lagrange/Eulerian (ALE) finite element simulation techniques. This mesh relaxer is derived by a variational principle for an unstructured 3D grid using finite elements, and incorporates hourglass controls in the numerical implementation. The diffusive coefficients are based on the geometric properties of the existing mesh, and are chosen so as to allow for a smooth grid that retains the general shape of the original mesh. The diffusive mesh relaxation algorithm is then applied to an ALE code system, and results from several test cases are discussed.

Dube, E.I.

1996-06-01T23:59:59.000Z

380

E-Print Network 3.0 - acetylene jet diffusion Sample Search Results  

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

the case of acetylene, we can... before they escape by diffusion. Conse- quently, the heat generated in acetylene has the same spatial... times in acetylene be- fore diffusion...

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


381

E-Print Network 3.0 - agar diffusion cytotoxicity Sample Search...  

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

diffusion cytotoxicity Search Powered by Explorit Topic List Advanced Search Sample search results for: agar diffusion cytotoxicity Page: << < 1 2 3 4 5 > >> 1 J. Embryol. exp....

382

E-Print Network 3.0 - ambipolar diffusion coefficient Sample...  

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

Summary: incorporating ambipolar diffusion, sometimes called "ion-neutral friction". It is important to understand how... in which ambipolar diffusion is the dominant...

383

E-Print Network 3.0 - au flux diffus Sample Search Results  

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

chauffage (Fig. l), le flux... lumineux diffus diminue au lieu d'augmenter. Temperature (OC) FIG. 1. -Etude du flux lumineux diffus par... ternaire perpendiculaire au...

384

E-Print Network 3.0 - advanced diffusion model Sample Search...  

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

of Michigan Collection: Geosciences 2 Oxygen self-diffusion fast-paths'' in titanite single crystals and a general method for deconvolving self-diffusion Summary:...

385

E-Print Network 3.0 - advanced stage diffuse Sample Search Results  

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

of Rochester Collection: Physics 95 Oxygen self-diffusion fast-paths'' in titanite single crystals and a general method for deconvolving self-diffusion Summary: Oxygen...

386

E-Print Network 3.0 - advanced diffusion studies Sample Search...  

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

State University Collection: Chemistry 3 Oxygen self-diffusion fast-paths'' in titanite single crystals and a general method for deconvolving self-diffusion Summary: could...

387

E-Print Network 3.0 - anomalous diffusion due Sample Search Results  

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

and Technology Collection: Mathematics 97 Oxygen self-diffusion fast-paths'' in titanite single crystals and a general method for deconvolving self-diffusion Summary: profile...

388

AGR-2 IRRADIATION TEST FINAL AS-RUN REPORT  

SciTech Connect (OSTI)

This document presents the as-run analysis of the AGR-2 irradiation experiment. AGR-2 is the second of the planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the U.S. Department of Energy as part of the Very High Temperature Reactor (VHTR) Technical Development Office (TDO) program. The objectives of the AGR-2 experiment are to: (a) Irradiate UCO (uranium oxycarbide) and UO2 (uranium dioxide) fuel produced in a large coater. Fuel attributes are based on results obtained from the AGR-1 test and other project activities. (b) Provide irradiated fuel samples for post-irradiation experiment (PIE) and safety testing. (c) Support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. The primary objective of the test was to irradiate both UCO and UO2 TRISO (tri-structural isotropic) fuel produced from prototypic scale equipment to obtain normal operation and accident condition fuel performance data. The UCO compacts were subjected to a range of burnups and temperatures typical of anticipated prismatic reactor service conditions in three capsules. The test train also includes compacts containing UO2 particles produced independently by the United States, South Africa, and France in three separate capsules. The range of burnups and temperatures in these capsules were typical of anticipated pebble bed reactor service conditions. The results discussed in this report pertain only to U.S. produced fuel. In order to achieve the test objectives, the AGR-2 experiment was irradiated in the B-12 position of the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) for a total irradiation duration of 559.2 effective full power days (EFPD). Irradiation began on June 22, 2010, and ended on October 16, 2013, spanning 12 ATR power cycles and approximately three and a half calendar years. The test contained six independently controlled and monitored capsules. Each U.S. capsule contained 12 compacts of either UCO or UO2 AGR coated fuel. No fuel particles failed during the AGR-2 irradiation. Final burnup values on a per compact basis ranged from 7.26 to 13.15% FIMA (fissions per initial heavy-metal atom) for UCO fuel, and 9.01 to 10.69% FIMA for UO2 fuel, while fast fluence values ranged from 1.94 to 3.47´1025 n/m2 (E >0.18 MeV) for UCO fuel, and from 3.05 to 3.53´1025 n/m2 (E >0.18 MeV) for UO2 fuel. Time-average volume-average (TAVA) temperatures on a capsule basis at the end of irradiation ranged from 987°C in Capsule 6 to 1296°C in Capsule 2 for UCO, and from 996 to 1062°C in UO2-fueled Capsule 3. By the end of the irradiation, all of the installed thermocouples (TCs) had failed. Fission product release-to-birth (R/B) ratios were quite low. In the UCO capsules, R/B values during the first three cycles were below 10-6 with the exception of the hotter Capsule 2, in which the R/Bs reached 2´10-6. In the UO2 capsule (Capsule 3), the R/B values during the first three cycles were below 10-7. R/B values for all following cycles are not reliable due to gas flow and cross talk issues.

Blaise, Collin

2014-07-01T23:59:59.000Z

389

Effects of multi-component diffusion and heat release on laminar diffusion flame liftoff  

SciTech Connect (OSTI)

Numerical simulations were conducted of the liftoff and stabilization phenomena of laminar jet diffusion flames of inert-diluted C{sub 3}H{sub 8} and CH{sub 4} fuels. Both non-reacting and reacting jets were investigated, including multi-component diffusivities and heat release effects (buoyancy and gas expansion). The role of Schmidt number for non-reacting jets was investigated, with no conclusive Schmidt number criterion for liftoff previously arrived at in similarity solutions. The cold-flow simulation for He-diluted CH{sub 4} fuel does not predict flame liftoff; however, adding heat release reaction lead to the prediction of liftoff, which is consistent with experimental observations. Including reaction was also found to improve liftoff height prediction for C{sub 3}H{sub 8} flames, with the flame base location differing from that in the similarity solution - the intersection of the stoichiometric and iso-velocity (equal to 1-D flame speed) is not necessary for flame stabilization (and thus liftoff). Possible mechanisms other than that proposed for similarity solution may better help to explain the stabilization and liftoff phenomena. (author)

Li, Zhiliang; Chen, Ruey-Hung [Department of Mechanical, Materials and Aerospace Engineering, University of Central Florida, Orlando, FL 32816-2450 (United States); Phuoc, Tran X. [National Energy Technology Laboratory, Department of Energy, P.O. Box 10940, MS 84-340, Pittsburgh, PA 15261 (United States)

2010-08-15T23:59:59.000Z

390

Uniform Diffusion of Acetonitrile inside Carbon Nanotubes Favors  

E-Print Network [OSTI]

materials. Nanoporous carbon exhibits excellent charge-discharge properties and a stable cyclic life. Moreover, activated composite carbon films generate high specific capacitance, laying the foundationUniform Diffusion of Acetonitrile inside Carbon Nanotubes Favors Supercapacitor Performance Oleg N

391

Modelling of monovacancy diffusion in W over wide temperature range  

SciTech Connect (OSTI)

The diffusion of monovacancies in tungsten is studied computationally over a wide temperature range from 1300?K until the melting point of the material. Our modelling is based on Molecular Dynamics technique and Density Functional Theory. The monovacancy migration barriers are calculated using nudged elastic band method for nearest and next-nearest neighbour monovacancy jumps. The diffusion pre-exponential factor for monovacancy diffusion is found to be two to three orders of magnitude higher than commonly used in computational studies, resulting in attempt frequency of the order 10{sup 15} Hz. Multiple nearest neighbour jumps of monovacancy are found to play an important role in the contribution to the total diffusion coefficient, especially at temperatures above 2/3 of T{sub m}, resulting in an upward curvature of the Arrhenius diagram. The probabilities for different nearest neighbour jumps for monovacancy in W are calculated at different temperatures.

Bukonte, L., E-mail: laura.bukonte@helsinki.fi; Ahlgren, T.; Heinola, K. [Department of Physics, University of Helsinki, P.O. Box 43, 00014 Helsinki (Finland)

2014-03-28T23:59:59.000Z

392

Perpendicular Diffusion of Energetic Particles in Collisionless Plasmas  

E-Print Network [OSTI]

A fundamental problem in plasma and astrophysics is the interaction between energetic particles and magnetized plasmas. In the current paper we focus on particle diffusion across the guide magnetic field. It is shown that the perpendicular diffusion coefficient depends only on the parallel diffusion coefficient and the Kubo number. Therefore, one can find four asymptotic limits depending on the values of these two parameters. These regimes are the quasilinear limit, the Kadomtsev & Pogutse limit, the scaling of Rechester & Rosenbluth, and the scaling found by Zybin & Istomin. In the current article we focus on the Rechester & Rosenbluth scenario because this was not discovered before in the context of collisionless plasmas. Examples and applications are discussed as well. We show that an energy independent ratio of perpendicular and parallel diffusion coefficients can be found and that this ratio can be very small but also close to unity. This is exactly what one observes in the solar wind.

Shalchi, Andreas

2015-01-01T23:59:59.000Z

393

Uranium(VI) Diffusion in Low-Permeability Subsurface Materials...  

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

Abstract: Uranium(VI) diffusion was investigated in a fine-grained saprolite sediment that was collected from U.S. Department of Energy (DOE) Oak Ridge site, TN, where...

394

Three essays on the development and diffusion of pharmaceutical innovations  

E-Print Network [OSTI]

The thesis comprises three essays on various aspects of the development and diffusion of pharmaceutical innovations, woven together by the idea that the production of clinical knowl- edge influences organizational design, ...

Azoulay, Pierre

2001-01-01T23:59:59.000Z

395

Research paper Drug diffusion and binding in ionizable interpenetrating networks  

E-Print Network [OSTI]

Research paper Drug diffusion and binding in ionizable interpenetrating networks from poly) (PVA), poly(acrylic acid) (PAA), and their interpenetrating networks (IPNs) were prepared using by measuring their equilibrium polymer volume fraction, equilibrium swelling ratio, and mesh size. Drug

Peppas, Nicholas A.

396

International diffusion practice : lessons from South Korea's New Village Movement  

E-Print Network [OSTI]

This research focuses on how South Korea's development model-namely, the Saemaul Undong, or the New Village Movement-is diffused internationally, in particular, to the developing country of Vietnam. South Korea's successful ...

Kim, Jung Hwa, M.C.P. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

397

A Simulation Study of Diffusion in Microporous Materials  

E-Print Network [OSTI]

of new zeolite-like materials. Phys. Chem. Chem. Phys. 13,screening of carbon-capture materials. Nat. Mater. 11, 633–Diffusion in nanoporous materials. (Wiley- VCH, 2012). 48.

Abouelnasr, Mahmoud Kamal Forrest

2013-01-01T23:59:59.000Z

398

Pre-plated reactive diffusion-bonded battery electrode plaques  

DOE Patents [OSTI]

A high strength, metallic fiber battery plaque is made using reactive diffusion bonding techniques, where a substantial amount of the fibers are bonded together by an iron-nickel alloy.

Maskalick, Nicholas J. (Pittsburgh, PA)

1984-01-01T23:59:59.000Z

399

Big Data Projects on Solar Tech Evolution and Diffusion  

Broader source: Energy.gov [DOE]

This is the meeting agenda from the Big Data Projects on Solar Technology Evolution and Diffusion kickoff meeting, held on July 15, 2013 in Arlington, VA and facilitated by the SunShot Initiative.

400

apparent diffusion coefficient: Topics by E-print Network  

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

4 sites). We exploit the dependence of the diffusion coefficient on the system size Yeh and Hummer, J. Phys. Chem. B 108, 15873 (2004) to obtain the size-independent...

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


401

apparent diffusion coefficients: Topics by E-print Network  

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

4 sites). We exploit the dependence of the diffusion coefficient on the system size Yeh and Hummer, J. Phys. Chem. B 108, 15873 (2004) to obtain the size-independent...

402

auto diffusion function: Topics by E-print Network  

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

angle of 30mathrm o are investigated. The analysis reveals that the influ... Sun, Y 2005-01-01 3 Etude par diffusion de Huang des auto-interstitiels dans un alliage...

403

Diffusion driven object propulsion in density stratified fluids  

E-Print Network [OSTI]

An experimental study was conducted in order to verify the appropriateness of a two dimensional model of the flow creating diffusion driven object propulsion in density stratified fluids. Initial flow field experiments ...

Lenahan, Conor (Conor P.)

2009-01-01T23:59:59.000Z

404

Synthesis of nanosize BPO{sub 4} under microwave irradiation  

SciTech Connect (OSTI)

Highlights: ? Nanosize BPO{sub 4} are prepared under microwave-irradiation conditions. ? This reaction is only performed at less than 640 W power for 2.5–5 min. ? The particles of sample irradiated at 400 W are 40–90 nm in size and well dispersed. ? A simple, fast and green procedure for synthesis of nanosize BPO{sub 4} is developed. -- Abstract: Nanosize BPO{sub 4} was synthesized using H{sub 3}BO{sub 3} and H{sub 3}PO{sub 4} (85%) as raw materials under microwave irradiation. This reaction was performed at powers lower than 640 W and irradiation time ranging from 2.5 min to 5 min, which were only a fraction of the time required for conventional synthetic procedures. The structure of the as-prepared BPO{sub 4} is analogous to that of a high cristobalite. The particle sizes of the samples irradiated at 640 and 400 W range from 40 nm to 90 nm and 30 nm to 60 nm, respectively. The effects of different conditions on the experimental outcome are also discussed.

Wang, Rui, E-mail: wr_wrwr@163.com [School of Chemistry and Materials Science, Liaoning Shihua University, Fushun 113001 (China) [School of Chemistry and Materials Science, Liaoning Shihua University, Fushun 113001 (China); School of Chemical Engineering, Dalian University of Technology, Dalian 116023 (China); Jiang, Heng; Gong, Hong; Zhang, Jun [School of Chemistry and Materials Science, Liaoning Shihua University, Fushun 113001 (China)] [School of Chemistry and Materials Science, Liaoning Shihua University, Fushun 113001 (China)

2012-08-15T23:59:59.000Z

405

Optical processing furnace with quartz muffle and diffuser plate  

DOE Patents [OSTI]

An optical furnace for annealing a process wafer is disclosed comprising a source of optical energy, a quartz muffle having a door to hold the wafer for processing, and a quartz diffuser plate to diffuse the light impinging on the quartz muffle; a feedback system with a light sensor located in the wall of the muffle is also provided for controlling the source of optical energy. 5 figs.

Sopori, B.L.

1996-11-19T23:59:59.000Z

406

Algorithm for anisotropic diffusion in hydrogen-bonded networks  

E-Print Network [OSTI]

In this paper I describe a specialized algorithm for anisotropic diffusion determined by a field of transition rates. The algorithm can be used to describe some interesting forms of diffusion that occur in the study of proton motion in a network of hydrogen bonds. The algorithm produces data that require a nonstandard method of spectral analysis which is also developed here. Finally, I apply the algorithm to a simple specific example.

Edoardo Milotti

2007-04-04T23:59:59.000Z

407

Classical phase diffusion in small hysteretic Josephson junctions  

SciTech Connect (OSTI)

The existence of classical phase diffusion in hysteretic junctions is demonstrated by quantitative agreement between experimental and simulated {ital I}-{ital V} curves. The simulations are based on a circuit that accurately models both the junction and its external shunting impedance at microwave frequencies. We show that the bias current at which the junction switches from the phase diffusion state to the voltage state is sensitive to dissipation at microwave frequencies.

Martinis, J.M.; Kautz, R.L. (National Institute of Standards and Technology, Boulder, Colorado 80303 (US))

1989-10-02T23:59:59.000Z

408

CO diffusion into amorphous H2O ices  

E-Print Network [OSTI]

The mobility of atoms, molecules and radicals in icy grain mantles regulate ice restructuring, desorption, and chemistry in astrophysical environments. Interstellar ices are dominated by H2O, and diffusion on external and internal (pore) surfaces of H2O-rich ices is therefore a key process to constrain. This study aims to quantify the diffusion kinetics and barrier of the abundant ice constituent CO into H2O dominated ices at low temperatures (15-23 K), by measuring the mixing rate of initially layered H2O(:CO2)/CO ices. The mixed fraction of CO as a function of time is determined by monitoring the shape of the infrared CO stretching band. Mixing is observed at all investigated temperatures on minute time scales, and can be ascribed to CO diffusion in H2O ice pores. The diffusion coefficient and final mixed fraction depend on ice temperature, porosity, thickness and composition. The experiments are analyzed by applying Fick's diffusion equation under the assumption that mixing is due to CO diffusion into an i...

Lauck, Trish; Shulenberger, Katherine; Rajappan, Mahesh; Oberg, Karin I; Cuppen, Herma M

2015-01-01T23:59:59.000Z

409

Microscopic thermal diffusivity mapping using an infrared camera  

SciTech Connect (OSTI)

Standard flash thermal diffusivity measurements utilize a single-point infrared detector to measure the average temperature rise of the sample surface after a heat pulse. The averaging of infrared radiation over the sample surface could smear out the microscopic thermal diffusivity variations in some specimens, especially in fiber-reinforced composite materials. A high-speed, high-sensitivity infrared camera was employed in this study of composite materials. With a special microscope attachment, the spatial resolution of the camera can reach 5.4 {micro}m. The images can then be processed to generate microscopic thermal diffusivity maps of the material. SRM 1462 stainless steel was tested to evaluate the accuracy of the system. Thermal diffusivity micrographs of carbon-carbon composites and SCS-6/borosilicate glass were generated. Thermal diffusivity values of the carbon fiber bundles parallel to the heat flow were found to be higher than the matrix material. A thermal coupling effect between SCS-6 fiber and matrix was observed. The thermal coupling and measured thermal diffusivity value of the fiber were also dependent upon the thickness of the specimen.

Wang, H.; Dinwiddie, R.B.

1997-12-31T23:59:59.000Z

410

AGR-1 Irradiation Test Final As-Run Report  

SciTech Connect (OSTI)

This document presents the as-run analysis of the AGR-1 irradiation experiment. AGR-1 is the first of eight planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the US Department of Energy (DOE) as part of the Next-Generation Nuclear Plant (NGNP) project. The objectives of the AGR-1 experiment are: 1. To gain experience with multi-capsule test train design, fabrication, and operation with the intent to reduce the probability of capsule or test train failure in subsequent irradiation tests. 2. To irradiate fuel produced in conjunction with the AGR fuel process development effort. 3. To provide data that will support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. In order to achieve the test objectives, the AGR-1 experiment was irradiated in the B-10 position of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) for a total duration of 620 effective full power days of irradiation. Irradiation began on December 24, 2006 and ended on November 6, 2009 spanning 13 ATR cycles and approximately three calendar years. The test contained six independently controlled and monitored capsules. Each capsule contained 12 compacts of a single type, or variant, of the AGR coated fuel. No fuel particles failed during the AGR-1 irradiation. Final burnup values on a per compact basis ranged from 11.5 to 19.6 %FIMA, while fast fluence values ranged from 2.21 to 4.39 ?1025 n/m2 (E >0.18 MeV). We’ll say something here about temperatures once thermal recalc is done. Thermocouples performed well, failing at a lower rate than expected. At the end of the irradiation, nine of the originally-planned 19 TCs were considered functional. Fission product release-to-birth (R/B) ratios were quite low. In most capsules, R/B values at the end of the irradiation were at or below 10-7 with only one capsule significantly exceeding this value. A maximum R/B of around 2?10-7 was reached at the end of the irradiation in Capsule 5. Several shakedown issues were encountered and resolved during the first three cycles. These include the repair of minor gas line leaks; repair of faulty gas line valves; the need to position moisture monitors in regions of low radiation fields for proper functioning; the enforcement of proper on-line data storage and backup, the need to monitor thermocouple performance, correcting for detector spectral gain shift, and a change in the mass flow rate range of the neon flow controllers.

Blaise P. Collin

2012-06-01T23:59:59.000Z

411

Irradiation behavior of miniature experimental uranium silicide fuel plates  

SciTech Connect (OSTI)

Uranium silicides, because of their relatively high uranium density, were selected as candidate dispersion fuels for the higher fuel densities required in the Reduced Enrichment Research and Test Reactor (RERTR) Program. Irradiation experience with this type of fuel, however, was limited to relatively modest fission densities in the bulk from, on the order of 7 x 10/sup 20/ cm/sup -3/, far short of the approximately 20 x 10/sup 20/ cm/sup -3/ goal established for the RERTR program. The purpose of the irradiation experiments on silicide fuels on the ORR, therefore, was to investigate the intrinsic irradiation behavior of uranium silicide as a dispersion fuel. Of particular interest was the interaction between the silicide particles and the aluminum matrix, the swelling behavior of the silicide particles, and the maximum volume fraction of silicide particles that could be contained in the aluminum matrix.

Hofman, G.L.; Neimark, L.A.; Mattas, R.F.

1983-01-01T23:59:59.000Z

412

Radiation Damage Study in Natural Zircon Using Neutrons Irradiation  

SciTech Connect (OSTI)

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

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

2011-03-30T23:59:59.000Z

413

Neutron and gamma irradiation damage to organic materials.  

SciTech Connect (OSTI)

This document discusses open literature reports which investigate the damage effects of neutron and gamma irradiation on polymers and/or epoxies - damage refers to reduced physical chemical, and electrical properties. Based on the literature, correlations are made for an SNL developed epoxy (Epon 828-1031/DDS) with an expected total fast-neutron fluence of {approx}10{sup 12} n/cm{sup 2} and a {gamma} dosage of {approx}500 Gy received over {approx}30 years at < 200 C. In short, there are no gamma and neutron irradiation concerns for Epon 828-1031/DDS. To enhance the fidelity of our hypotheses, in regards to radiation damage, we propose future work consisting of simultaneous thermal/irradiation (neutron and gamma) experiments that will help elucidate any damage concerns at these specified environmental conditions.

White, Gregory Von, II; Bernstein, Robert

2012-04-01T23:59:59.000Z

414

On the Absorption and Redistribution of Energy in Irradiated Planets  

E-Print Network [OSTI]

We present a sequence of toy models for irradiated planet atmospheres, in which the effects of geometry and energy redistribution are modelled self-consistently. We use separate but coupled grey atmosphere models to treat the ingoing stellar irradiation and outgoing planetary reradiation. We investigate how observed quantities such as full phase secondary eclipses and orbital phase curves depend on various important parameters, such as the depth at which irradiation is absorbed and the depth at which energy is redistributed. We also compare our results to the more detailed radiative transfer models in the literature, in order to understand how those map onto the toy model parameter space. Such an approach can prove complementary to more detailed calculations, in that they demonstrate, in a simple way, how the solutions change depending on where, and how, energy redistribution occurs. As an example of the value of such models, we demonstrate how energy redistribution and temperature equilibration at moderate o...

Hansen, Brad

2008-01-01T23:59:59.000Z

415

[Grain boundary and interface kinetics during ion irradiation  

SciTech Connect (OSTI)

Proposed here is renewed support of a research program focused on interface motion and phase transformation during ion irradiation, with emphasis on elemental semiconductors. Broadly speaking, the aims of this program are to explore defect kinetics in amorphous and crystalline semiconductors, and to relate defect dynamics to interface motion and phase transformations. Over the last three years, we initiated a program under DOE support to explore crystallization and amorphization of elemental semiconductors under irradiation. This research has enabled new insights about the nature of defects in amorphous semiconductors and about microstructural evolution in the early stages of crystallization. In addition, we have demonstrated almost arbitrary control over the relative rates of crystal nucleation and crystal growth in silicon. As a result, the impinged grain microstructure of thin (100 nm) polycrystalline films crystallized under irradiation can be controlled with grain sizes ranging from a few nanometers to several micrometers, which may have interesting technological implications.

Atwater, H.A.

1991-12-31T23:59:59.000Z

416

(Grain boundary and interface kinetics during ion irradiation)  

SciTech Connect (OSTI)

Proposed here is renewed support of a research program focused on interface motion and phase transformation during ion irradiation, with emphasis on elemental semiconductors. Broadly speaking, the aims of this program are to explore defect kinetics in amorphous and crystalline semiconductors, and to relate defect dynamics to interface motion and phase transformations. Over the last three years, we initiated a program under DOE support to explore crystallization and amorphization of elemental semiconductors under irradiation. This research has enabled new insights about the nature of defects in amorphous semiconductors and about microstructural evolution in the early stages of crystallization. In addition, we have demonstrated almost arbitrary control over the relative rates of crystal nucleation and crystal growth in silicon. As a result, the impinged grain microstructure of thin (100 nm) polycrystalline films crystallized under irradiation can be controlled with grain sizes ranging from a few nanometers to several micrometers, which may have interesting technological implications.

Atwater, H.A.

1991-01-01T23:59:59.000Z

417

TEST RESULTS FROM GAMMA IRRADIATION OF ALUMINUM OXYHYDROXIDES  

SciTech Connect (OSTI)

Hydrated metal oxides or oxyhydroxides boehmite and gibbsite that can form on spent aluminum-clad nuclear fuel assemblies during in-core and post-discharge wet storage were exposed as granular powders to gamma irradiation in a {sup 60}Co irradiator in closed laboratory test vessels with air and with argon as separate cover gases. The results show that boehmite readily evolves hydrogen with exposure up to a dose of 1.8 x 10{sup 8} rad, the maximum tested, in both a full-dried and moist condition of the powder, whereas only a very small measurable quantity of hydrogen was generated from the granular powder of gibbsite. Specific information on the test setup, sample characteristics, sample preparation, irradiation, and gas analysis are described.

Fisher, D.; Westbrook, M.; Sindelar, R.

2012-02-01T23:59:59.000Z

418

Physiological Interaction of Heart and Lung in Thoracic Irradiation  

SciTech Connect (OSTI)

Introduction: The risk of early radiation-induced lung toxicity (RILT) limits the dose and efficacy of radiation therapy of thoracic tumors. In addition to lung dose, coirradiation of the heart is a known risk factor in the development RILT. The aim of this study was to identify the underlying physiology of the interaction between lung and heart in thoracic irradiation. Methods and Materials: Rat hearts, lungs, or both were irradiated to 20 Gy using high-precision proton beams. Cardiopulmonary performance was assessed using breathing rate measurements and F{sup 18}-fluorodeoxyglucose positron emission tomography ({sup 18}F-FDG-PET) scans biweekly and left- and right-sided cardiac hemodynamic measurements and histopathology analysis at 8 weeks postirradiation. Results: Two to 12 weeks after heart irradiation, a pronounced defect in the uptake of {sup 18}F-FDG in the left ventricle (LV) was observed. At 8 weeks postirradiation, this coincided with LV perivascular fibrosis, an increase in LV end-diastolic pressure, and pulmonary edema in the shielded lungs. Lung irradiation alone not only increased pulmonary artery pressure and perivascular edema but also induced an increased LV relaxation time. Combined irradiation of lung and heart induced pronounced increases in LV end-diastolic pressure and relaxation time, in addition to an increase in right ventricle end-diastolic pressure, indicative of biventricular diastolic dysfunction. Moreover, enhanced pulmonary edema, inflammation and fibrosis were also observed. Conclusions: Both lung and heart irradiation cause cardiac and pulmonary toxicity via different mechanisms. Thus, when combined, the loss of cardiopulmonary performance is intensified further, explaining the deleterious effects of heart and lung coirradiation. Our findings show for the first time the physiological mechanism underlying the development of a multiorgan complication, RILT. Reduction of dose to either of these organs offers new opportunities to improve radiation therapy treatment of thoracic tumors, potentially facilitating increased treatment doses and tumor control.

Ghobadi, Ghazaleh; Veen, Sonja van der [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands) [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Bartelds, Beatrijs [Center for Congenital Heart Disease, Beatrix Children Hospital, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)] [Center for Congenital Heart Disease, Beatrix Children Hospital, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Boer, Rudolf A. de [Department of Cardiology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)] [Department of Cardiology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Dickinson, Michael G. [Center for Congenital Heart Disease, Beatrix Children Hospital, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)] [Center for Congenital Heart Disease, Beatrix Children Hospital, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Jong, Johan R. de [Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)] [Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Faber, Hette; Niemantsverdriet, Maarten [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands) [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Brandenburg, Sytze [Kernfysisch Versneller Instituut, University of Groningen, Groningen (Netherlands)] [Kernfysisch Versneller Instituut, University of Groningen, Groningen (Netherlands); Berger, Rolf M.F. [Center for Congenital Heart Disease, Beatrix Children Hospital, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)] [Center for Congenital Heart Disease, Beatrix Children Hospital, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Langendijk, Johannes A. [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)] [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Coppes, Robert P. [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands) [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Luijk, Peter van, E-mail: p.van.luijk@umcg.nl [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)

2012-12-01T23:59:59.000Z

419

Threshold irradiation dose for amorphization of silicon carbide  

SciTech Connect (OSTI)

The amorphization of silicon carbide due to ion and electron irradiation is reviewed with emphasis on the temperature-dependent critical dose for amorphization. The effect of ion mass and energy on the threshold dose for amorphization is summarized, showing only a weak dependence near room temperature. Results are presented for 0.56 MeV silicon ions implanted into single crystal 6H-SiC as a function of temperature and ion dose. From this, the critical dose for amorphization is found as a function of temperature at depths well separated from the implanted ion region. Results are compared with published data generated using electrons and xenon ions as the irradiating species. High resolution TEM analysis is presented for the Si ion series showing the evolution of elongated amorphous islands oriented such that their major axis is parallel to the free surface. This suggests that surface or strain effects may be influencing the apparent amorphization threshold. Finally, a model for the temperature threshold for amorphization is described using the Si ion irradiation flux and the fitted interstitial migration energy which was found to be {approximately}0.56eV. This model successfully explains the difference in the temperature dependent amorphization behavior of SiC irradiated with 0.56 MeV Si{sup +} at 1 x 10{sup -3} dpa/s and with fission neutrons irradiated at 1 x 10{sup -6} dpa/s irradiated to 15 dpa in the temperature range of {approximately}340{+-}10K.

Snead, L.L.; Zinkle, S.J.

1997-03-01T23:59:59.000Z

420

Structural and luminescent properties of electron-irradiated silicon  

SciTech Connect (OSTI)

Structural defects induced by electron irradiation of p-Cz-Si wafers were identified. The influence of the annealing conditions in a chlorine-containing atmosphere on the structural and luminescent properties of the samples was examined. Light-emitting diodes based on electron-irradiated and high-temperature-annealed wafers were fabricated by a vapour-phase epitaxy technique and their luminescence properties were studied. A high-intensity dislocation-related D1 line was observed at 1.6 ?m in the room-temperature electroluminescence spectrum.

Sobolev, N. A.; Loshachenko, A. S. [Ioffe Physical-Technical Institute, 194021 St. Petersburg, Russia and Fok Institute of Physics, St. Petersburg State University, 198504 St. Petersburg (Russian Federation); Aruev, P. N.; Kalyadin, A. E.; Shek, E. I.; Zabrodskiy, V. V. [Ioffe Physical-Technical Institute, 194021 St. Petersburg (Russian Federation); Shtel'makh, K. F. [Ioffe Physical-Technical Institute, 194021 St. Petersburg, Russia and St. Petersburg State Technical University, 195251 St. Petersburg (Russian Federation); Vdovin, V. I. [Rzhanov Institute of Semiconductor Physics, 630090 Novosibirsk (Russian Federation); Xiang, Luelue; Yang, Deren [State Key Laboratory of Silicon Materials and Department of Materials Science and Engineering, Zhejiang University, 310027 Hangzhou (China)

2014-02-21T23:59:59.000Z

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


421

Fission product release from irradiated LWR fuel under accident conditions  

SciTech Connect (OSTI)

Fission product release from irradiated LWR fuel is being studied by heating fuel rod segments in flowing steam and an inert carrier gas to simulate accident conditions. Fuels with a range of irradiation histories are being subjected to several steam flow rates over a wide range of temperatures. Fission product release during each test is measured by gamma spectroscopy and by detailed examination of the collection apparatus after the test has been completed. These release results are complemented by a detailed posttest examination of samples of the fuel rod segment. Results of release measurements and fuel rod characterizations for tests at 1400 through 2000/sup 0/C are presented in this paper.

Strain, R.V.; Sanecki, J.E.; Osborne, M.F.

1984-01-01T23:59:59.000Z

422

Thermal response of photovoltaic cell to laser beam irradiation  

E-Print Network [OSTI]

This paper firstly presents the concept of using dual laser beam to irradiate the photovoltaic cell, so as to investigate the temperature dependency of the efficiency of long distance energy transmission. Next, the model on the multiple reflection and absorption of any monochromatic light in multilayer structure has been established, and the heat generation in photovoltaic cell has been interpreted in this work. Then, the finite element model has been set up to calculate the temperature of photovoltaic cell subjected to laser irradiation. Finally, the effect of temperature elevation on the efficiency and reliability of photovoltaic cell has been discussed to provide theoretical references for designing the light-electricity conversion system.

Yuan, Yu-Chen

2014-01-01T23:59:59.000Z

423

The effects of gamma irradiation on Serratia marcescens  

E-Print Network [OSTI]

that there was little difference in the five strains. This suggests that growth rates do not alter the survival curves. The effects of irradiation on pigmentation ability were studied using the wild type, nims, and the more-resistant R-25. Pyrex tubes, 16 x 150 mm...). 5. D. L. Dewey, The X-ray sensitivity of Serratia marcescens. Radiation Res. 19, 64-87 (1963). 6. D. L. Dewey, Effect of irradiation on the ability of Pseudonrtnas to synthesize two inducible enzymes. Radiation Res. 21, 367-75 (1964). 7. F...

Bartlett, William Thomas

1969-01-01T23:59:59.000Z

424

Properties of solar gravity mode signals in total irradiance observations  

SciTech Connect (OSTI)

Further evidence has been found that a significant fraction of the gravity mode power density in the total irradiance observations appears in sidebands of classified eigenfrequencies. These sidebands whose amplitudes vary from year to year are interpreted as harmonics of the rotational frequencies of the nonuniform solar surface. These findings are for non axisymmetric modes and corroborate the findings of Kroll, Hill and Chen for axisymmetric modes. It is demonstrated the the generation of the sidebands lifts the usual restriction on the parity of the eigenfunctions for modes detectable in total irradiance observations. 14 refs.

Kroll, R.J.; Chen, J.; Hill, H.A.

1988-01-01T23:59:59.000Z

425

Light water reactor mixed-oxide fuel irradiation experiment  

SciTech Connect (OSTI)

The United States Department of Energy Office of Fissile Materials Disposition is sponsoring and Oak Ridge National Laboratory (ORNL) is leading an irradiation experiment to test mixed uranium-plutonium oxide (MOX) fuel made from weapons-grade (WG) plutonium. In this multiyear program, sealed capsules containing MOX fuel pellets fabricated at Los Alamos National Laboratory (LANL) are being irradiated in the Advanced Test Reactor (ATR) at the Idaho National Engineering and Environmental Laboratory (INEEL). The planned experiments will investigate the utilization of dry-processed plutonium, the effects of WG plutonium isotopics on MOX performance, and any material interactions of gallium with Zircaloy cladding.

Hodge, S.A.; Cowell, B.S. [Oak Ridge National Lab., TN (United States); Chang, G.S.; Ryskamp, J.M. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab.

1998-06-01T23:59:59.000Z

426

Irradiation Effects on Human Cortical Bone Fracture Behavior  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFunInfrared LandResponsesIon/Surface ReactionsIrradiation Effects onIrradiation

427

Irradiation Effects on Human Cortical Bone Fracture Behavior  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFunInfrared LandResponsesIon/Surface ReactionsIrradiation EffectsIrradiation

428

SLIGHTLY IRRADIATED FUEL (SIF) INTERIM DISPOSITION PROJECT  

SciTech Connect (OSTI)

CH2M HILL Plateau Remediation Company (CH2M HILL PRC) is proud to submit the Slightly Irradiated Fuel (SIF) Interim Disposition Project for consideration by the Project Management Institute as Project of the Year for 2010. The SIF Project was a set of six interrelated sub-projects that delivered unique stand-alone outcomes, which, when integrated, provided a comprehensive and compliant system for storing high risk special nuclear materials. The scope of the six sub-projects included the design, construction, testing, and turnover of the facilities and equipment, which would provide safe, secure, and compliant Special Nuclear Material (SNM) storage capabilities for the SIF material. The project encompassed a broad range of activities, including the following: Five buildings/structures removed, relocated, or built; Two buildings renovated; Structural barriers, fencing, and heavy gates installed; New roadways and parking lots built; Multiple detection and assessment systems installed; New and expanded communication systems developed; Multimedia recording devices added; and A new control room to monitor all materials and systems built. Project challenges were numerous and included the following: An aggressive 17-month schedule to support the high-profile Plutonium Finishing Plant (PFP) decommissioning; Company/contractor changeovers that affected each and every project team member; Project requirements that continually evolved during design and construction due to the performance- and outcome-based nature ofthe security objectives; and Restrictions imposed on all communications due to the sensitive nature of the projects In spite of the significant challenges, the project was delivered on schedule and $2 million under budget, which became a special source of pride that bonded the team. For years, the SIF had been stored at the central Hanford PFP. Because of the weapons-grade piutonium produced and stored there, the PFP had some of the tightest security on the Hanford nuclear reservation. Workers had to pass through metal detectors when they arrived at the plant and materials leaving the plant had to be scanned for security reasons. Whereas other high-security nuclear materials were shipped from the PFP to Savannah River, S.C. as part ofa Department of Energy (DOE) program to consolidate weapons-grade plutonium, it was determined that the SIF should remain onsite pending disposition to a national repository. Nevertheless, the SIF still requires a high level of security that the PFP complex has always provided. With the 60-year PFP mission of producing and storing plutonium concluded, the environmental cleanup plans for Hanford call for the demolition of the 63-building PFP complex. Consequently, if the SIF remained at PFP it not only would have interfered with the environmental cleanup plans, but would have required $100 million in facility upgrades to meet increased national security requirements imposed after the 9/11 terrorist attacks. A new smaller and more cost-effective area was needed to store this material, which led to the SIF Project. Once the SIF project was successfully completed and the SIF was safely removed from PFP, the existing Protected Area at PFP could be removed, and demolition could proceed more quickly without being encumbered by restrictive security requirements that an active Protected Area requires. The lightened PFP security level brought by safely removing and storing the SIF would also yield lowered costs for deactivation and demolition, as well as reduce overall life-cycle costs.

NORTON SH

2010-02-23T23:59:59.000Z

429

Geophysical Research Abstracts Vol. 13, EGU2011-9360-4, 2011  

E-Print Network [OSTI]

Tech and the German Aerospace Center (DLR), aiming at estimating surface downwelling solar irradiance (SSI of cloudless shortwave solar spectra incident on horizontal, tilted, or tracking surfaces, Solar energy, vol irradiance database for worldwide solar heat gain and building cooling load calculations. Solar Energy, vol

Paris-Sud XI, Université de

430

Thermal-wave resonator cavity design and measurements of the thermal diffusivity of liquids  

E-Print Network [OSTI]

Thermal-wave resonator cavity design and measurements of the thermal diffusivity of liquids J. A for the measurement of the thermal diffusivity of liquids. The thermal diffusivities of distilled water, glycerol the thermal diffusivity of gases, particularly air,8,9 and vapors10 to a high degree of precision. Although

Mandelis, Andreas

431

Diffusion and magnetic relaxation in model porous media Aniket Bhattacharya and S. D. Mahanti  

E-Print Network [OSTI]

-dimensional analogs resemble commercially prepared Vycors and aerogels. When diffusion rates are compared for two

Bhattacharya, Aniket

432

Chapter 4. Permeability, Diffusivity, and Solubility of Gas and Solute Through Polymers  

E-Print Network [OSTI]

The diffusion of small molecules into polymers is a function of both the polymer and the diffusant. Factors which influence diffusion include: (1) the molecular size and physical state of the diffusant; (2) the morphology of the polymer; (3) the compatibility or solubility limit of the solute within the polymer matrix; (4) the volatility of the solute; (5) and the surface or interfacial

unknown authors

433

NUMERICAL CALCULATIONS FOR THE ASYMPTOTIC, DIFFUSION DOMINATED MASS-TRANSFER COEFFICIENT IN PACKED BED REACTORS  

E-Print Network [OSTI]

Calculations for the Asymptotic, Diffusion Dominated Mass-Transfer Coefficient in Packed Bed Reactors

Fedkiw, Peter

2011-01-01T23:59:59.000Z

434

Radiochemical Transformation of High Pressure Methane under Gamma, Electron, and Neutron Irradiation  

E-Print Network [OSTI]

The chemical effects of irradiation on high pressure methane and noble gas mixtures were investigated using gamma, electron beam, and neutron irradiation sources. The gamma source used was the La-140 source from the Nuclear Science Center (NSC...

Clemens, Jeffrey Tyler

2014-05-01T23:59:59.000Z

435

Etch-free Formation of Porous Silicon by High-energy Ion Irradiation...  

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

Etch-free Formation of Porous Silicon by High-energy Ion Irradiation. Etch-free Formation of Porous Silicon by High-energy Ion Irradiation. Abstract: In this study, porous silicon...

436

U.S. consumers' acceptance and willingness to buy irradiated food  

E-Print Network [OSTI]

in their decisions regarding irradiated foods. Education programs seem to have positive effects on shaping consumer opinion about irradiation, which can improve the safety of food products. Thus, the results of this study provide useful information required...

Poghosyan, Arsen Vahagn

2002-01-01T23:59:59.000Z

437

Radiosensitization Strategies for Enhanced E-beam Irradiation Treatment of Fresh Produce  

E-Print Network [OSTI]

necessary to develop treatments that will reduce their prevalence and numbers on fresh produce. Irradiation is a penetrating nonthermal treatment that effectively eliminates bacteria. Irradiated baby spinach leaves up to 1.0 kGy showed negligible (P>0...

Gomes, Carmen

2011-08-08T23:59:59.000Z

438

Conjugated linoleic acid reduces lipid oxidation in irradiated, cooked ground beef patties  

E-Print Network [OSTI]

This study was conducted to examine the antioxidative effect of conjugated linoleic acid (CLA) in irradiated, cooked ground beef patties. The hypothesis was that CLA would be retained during irradiation and would reduce lipid oxidation...

Chae, Sung Hee

2007-09-17T23:59:59.000Z

439

Electron Irradiation Induced Changes of the Electrical Transport Properties of Graphene  

E-Print Network [OSTI]

. In addition, the effect of electron irradiation on a PMMA (Poly Methyl Methacrylate)/Graphene bilayer was studied. We observed a deterioration of the electrical transport properties of a graphene FET. Prior to electron irradiation, we observed that the PMMA...

Woo, Sung Oh

2014-08-06T23:59:59.000Z

440

E-Print Network 3.0 - alleviates irradiation-induced brain Sample...  

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

irradiation-induced brain Search Powered by Explorit Topic List Advanced Search Sample search results for: alleviates irradiation-induced brain Page: << < 1 2 3 4 5 > >> 1 ORIGINAL...

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


441

E-Print Network 3.0 - animal irradiation preliminary Sample Search...  

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

Centre de mathmatiques Collection: Mathematics 97 Irradiation of Nd-Fe-B Permanent Magnets with APS Bending Magnet X-rays and 60 Summary: 1 Irradiation of Nd-Fe-B...

442

E-Print Network 3.0 - accelerator irradiation issledovaniya Sample...  

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

Group Collection: Physics 66 Irradiation of Nd-Fe-B Permanent Magnets with APS Bending Magnet X-rays and 60 Summary: of 260 Mrad was used to irradiate Nd-Fe-B sample magnets with...

443

Ion irradiation of Fe-Fe oxide core-shell nanocluster films:...  

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

irradiation of Fe-Fe oxide core-shell nanocluster films: Effect of interface on stability of magnetic properties. Ion irradiation of Fe-Fe oxide core-shell nanocluster films:...

444

Mutation Research 568 (2004) 4148 Detection of chromosomal instability in -irradiated  

E-Print Network [OSTI]

in the progeny at subsequent generations (genomic instability) and in non-irradiated neighbors of irradiated the link between the radiation-induced phenomena of genomic instability and the bystander effect. © 2004

445

Diffusive parameters of tritiated water and uranium in chalk  

SciTech Connect (OSTI)

The Cretaceous Chalk of North-western Europe exhibits a double porosity (matrix and fracture) providing pathways for both slow and rapid flow of water. The present study aims at understanding and predicting the contaminant transfer properties through a significant section of this formation, with a particular emphasis on diffusion. This requires to study the nature of porosity and to perform diffusion experiments in representative samples using uranium and tritiated water (HTO), respectively taken as a reactive tracer and an inert one. The diffusive parameters, i.e. the accessible porosity and the effective diffusion coefficient were determined. Additional information was obtained with mercury porosimetry, gravimetric water content, textural and mineralogical characterization. The diffusion tests performed with HTO appear to be the best method to measure the total accessible porosity in any type of porous media, especially those having large pore size distributions. Our study demonstrates that classical gravimetric water content measurements are not sensitive to the reduction in pore size as opposed to HTO diffusion tests because capillary water is not extracted by conventional gravimetric method but can still be probed by diffusion experiments. We found effective diffusion coefficients D{sub e}(U(VI)) near 4 x 10{sup -10} m{sup 2}s{sup -1}). The slower migration of U(VI) compared to HTO indicates sorption, with R{sub d}(U(VI)) from 100 to 360 mL g{sup -1}. These values are one order of magnitude larger than other determinations of the U(VI) sorption coefficient because only the matrix porosity is concerned here. The migration of U(VI) in chalk is only limited by sorption on ancillary Fe-Pb-bearing minerals. Transport of HTO and U(VI) is independent of the porosity distribution. Uranium diffusion in the chalk matrix porosity is fast enough to allow the total invasion of the pore space within characteristic time scales of the order of 1000 years. This results in a partitioning of uranium velocities in fracture flow and matrix flow proportionally to the respective fracture and matrix porosities. (authors)

Descostes, M. [CEA, DEN/DANS/DPC/SECR/Laboratory of Radionuclides Migration Measurements and Modelling, F-91191 Gif-sur-Yvette, (France); UMR 8587 CEA, Universite d'Evry, CNRS, (France); Pili, E. [CEA, DAM, DIF, F-91297 Arpajon, (France); Institut de Physique du Globe, Sorbonne Paris Cite, 1 rue Jussieu, 75238 Paris cedex 05, (France); Felix, O.; Frasca, B.; Radwan, J.; Juery, A. [CEA, DEN/DANS/DPC/SECR/Laboratory of Radionuclides Migration Measurements and Modelling, F-91191 Gif-sur-Yvette, (France)

2012-07-15T23:59:59.000Z

446

E-Print Network 3.0 - argon ion irradiation Sample Search Results  

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

mathmatiques Collection: Mathematics 3 Straightening Suspended Single Walled Carbon Nanotubes by Ion Irradiation Summary: Straightening Suspended Single Walled Carbon Nanotubes...

447

Irradiation Testing of Blanket Materials at the HFR Petten with On Line Tritium Monitoring  

SciTech Connect (OSTI)

Irradiation experiments are performed in support of fusion blanket technology development. These comprise ceramic solid breeder materials, and a liquid Lithium Lead alloy, as well as blanket subassemblies and components. Experimental facilities at the HFR to study tritium release, permeation characteristics, and neutron irradiation performance, have recently been extended. This paper gives an overview on the tritium breeding materials irradiation programme and describes the facilities required for irradiation testing and on-line tritium measurement.

Magielsen, A.J.; Laan, J.G. van der; Hegeman, J.B.J.; Stijkel, M.P.; Ooijevaar, M.A.G

2005-07-15T23:59:59.000Z

448

Test Program for High Efficiency Gas Turbine Exhaust Diffuser  

SciTech Connect (OSTI)

This research relates to improving the efficiency of flow in a turbine exhaust, and thus, that of the turbine and power plant. The Phase I SBIR project demonstrated the technical viability of “strutlets” to control stalls on a model diffuser strut. Strutlets are a novel flow-improving vane concept intended to improve the efficiency of flow in turbine exhausts. Strutlets can help reduce turbine back pressure, and incrementally improve turbine efficiency, increase power, and reduce greenhouse gas emmission. The long-term goal is a 0.5 percent improvement of each item, averaged over the US gas turbine fleet. The strutlets were tested in a physical scale model of a gas turbine exhaust diffuser. The test flow passage is a straight, annular diffuser with three sets of struts. At the end of Phase 1, the ability of strutlets to keep flow attached to struts was demonstrated, but the strutlet drag was too high for a net efficiency advantage. An independently sponsored followup project did develop a highly-modified low-drag strutlet. In combination with other flow improving vanes, complicance to the stated goals was demonstrated for for simple cycle power plants, and to most of the goals for combined cycle power plants using this particular exhaust geometry. Importantly, low frequency diffuser noise was reduced by 5 dB or more, compared to the baseline. Appolicability to other diffuser geometries is yet to be demonstrated.

Norris, Thomas R.

2009-12-31T23:59:59.000Z

449

Diffusion current in a system of coupled Josephson junctions  

SciTech Connect (OSTI)

The role of a diffusion current in the phase dynamics of a system of coupled Josephson junctions (JJs) has been analyzed. It is shown that, by studying the temporal dependences of the superconducting, quasi-particle, diffusion, and displacement currents and the dependences of average values of these currents on the total current, it is possible to explain the main features of the current-voltage characteristic (CVC) of the system. The effect of a diffusion current on the character of CVC branching in the vicinity of a critical current and in the region of hysteresis, as well as on the part of CVC branch corresponding to a parametric resonance in the system is demonstrated. A clear interpretation of the differences in the character of CVC branching in a model of capacitively coupled JJs (CCJJ model) and a model of capacitive coupling with diffusion current (CCJJ+DC model) is proposed. It is shown that a decrease in the diffusion current in a JJ leads to the switching of this junction to an oscillating state. The results of model calculations are qualitatively consistent with the experimental data.

Shukrinov, Yu. M., E-mail: shukrinv@theor.jinr.ru; Rahmonov, I. R. [Joint Institute for Nuclear Research (Russian Federation)

2012-08-15T23:59:59.000Z

450

Diffusivity anomaly in modified Stillinger-Weber liquids  

SciTech Connect (OSTI)

By modifying the tetrahedrality (the strength of the three body interactions) in the well-known Stillinger-Weber model for silicon, we study the diffusivity of a series of model liquids as a function of tetrahedrality and temperature at fixed pressure. Previous work has shown that at constant temperature, the diffusivity exhibits a maximum as a function of tetrahedrality, which we refer to as the diffusivity anomaly, in analogy with the well-known anomaly in water upon variation of pressure at constant temperature. We explore to what extent the structural and thermodynamic changes accompanying changes in the interaction potential can help rationalize the diffusivity anomaly, by employing the Rosenfeld relation between diffusivity and the excess entropy (over the ideal gas reference value), and the pair correlation entropy, which provides an approximation to the excess entropy in terms of the pair correlation function. We find that in the modified Stillinger-Weber liquids, the Rosenfeld relation works well above the melting temperatures but exhibits deviations below, with the deviations becoming smaller for smaller tetrahedrality. Further we find that both the excess entropy and the pair correlation entropy at constant temperature go through maxima as a function of the tetrahedrality, thus demonstrating the close relationship between structural, thermodynamic, and dynamical anomalies in the modified Stillinger-Weber liquids.

Sengupta, Shiladitya [TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500089 (India)] [TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500089 (India); Vasisht, Vishwas V. [Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur Campus, Bangalore 560064 (India)] [Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur Campus, Bangalore 560064 (India); Sastry, Srikanth [TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500089 (India) [TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500089 (India); Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur Campus, Bangalore 560064 (India)

2014-01-28T23:59:59.000Z

451

SURVEILLANCE OF PHOTOVOLTAIC SOLAR ENERGY SYSTEMS USING METEOSAT DERIVED IRRADIANCES  

E-Print Network [OSTI]

SURVEILLANCE OF PHOTOVOLTAIC SOLAR ENERGY SYSTEMS USING METEOSAT DERIVED IRRADIANCES Annette Hammer.Heinemann@uni-oldenburg.de 2Enecolo AG, Lindhof 235, CH-8617 M¨onchaltorf 3Fraunhofer Insitute for Solar Energy Systems Wiemken3, Hans Georg Beyer4, Vincent van Dijk5, Jethro Betcke5 1Dept. of Energy and Semiconductor Research

Heinemann, Detlev

452

SOLAR IRRADIANCE FORECASTING FOR THE MANAGEMENT OF SOLAR ENERGY SYSTEMS  

E-Print Network [OSTI]

SOLAR IRRADIANCE FORECASTING FOR THE MANAGEMENT OF SOLAR ENERGY SYSTEMS Detlev Heinemann Oldenburg.girodo@uni-oldenburg.de ABSTRACT Solar energy is expected to contribute major shares of the future global energy supply. Due to its and solar energy conversion processes has to account for this behaviour in respective operating strategies

Heinemann, Detlev

453

The modelling of irradiation embrittlement in submerged-arc welds  

SciTech Connect (OSTI)

Until very recently, the irradiation embrittlement behavior of submerged-arc welds has been interpreted in terms of two mechanisms, namely a matrix damage component and an additional component due to the irradiation-enhanced production of copper-rich precipitates. However, some of the weld specimens from a recent accelerated re-irradiation experiment have shown high Charpy shifts which exceeded the values expected from the measured shift in yield stress. Microstructural examination has revealed the occurrence of intergranular fracture (IGF) in these specimens, accompanied by grain boundary segregation of phosphorus. Theoretical models were developed to predict the parametric dependence of irradiation-enhanced phosphorus segregation on experimental variables. Using these parametric forms, along with the concept of a critical level of segregation for the onset of IGF instead of cleavage, a three mechanism trend curve has been developed. The form of this trend curve, taking into account IGF as well as matrix and copper embrittlement, is thus mechanistically based. The constants in the equation, however, are obtained by a statistical fit to the actual Charpy shift database.

Bolton, C.J.; Buswell, J.T.; Jones, R.B.; Moskovic, R.; Priest, R.H. [Nuclear Electric plc, Berkeley (United Kingdom). Berkeley Technology Centre

1996-12-31T23:59:59.000Z

454

Simultaneous Irradiation and Imaging of Blood Vessels During Pulsed  

E-Print Network [OSTI]

energy produced hemorrhage. In larger vessels, coagula often were attached to the superficial vessel wall; port wine stains INTRODUCTION Previous studies examining the effect of la- ser irradiation on cutaneous preparation. The short pulse duration illus- trated an extreme; energy was deposited quickly Contract grant

Barton, Jennifer K.

455

Development of a chemical dosimeter for electron beam food irradiation  

E-Print Network [OSTI]

uniform irradiation treatment on apple-phantoms (a complex shaped target) and GAFCHROMIC® HD-810 films using electron beams from (1) a 2 MeV Van de Graaff (VDG) accelerator, (2) a 10 MeV Linear Accelerator (LINAC), and (3) X-rays from a 5 MeV LINAC...

Rivadeneira, Ramiro Geovanny

2006-08-16T23:59:59.000Z

456

RETHINKING SATELLITE BASED SOLAR IRRADIANCE MODELLING R. W. Mueller  

E-Print Network [OSTI]

of Oldenburg, D-26111 Oldenburg; 2-University of Bergen; 3-Fraunhofer Institute for Solar Energy Systems; 4-German Aerospace Center; 5-Ecole des Mines de Paris ABSTRACT Accurate solar irradiance data are not only necessary for an efficient planning and operation of solar energy systems. Within the European project

Heinemann, Detlev

457

adt materials irradiated: Topics by E-print Network  

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

adt materials irradiated First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Umsetzung von ADTs ADT in...

458

Large Animal Irradiation J. Daniel Bourland, PhD  

E-Print Network [OSTI]

Departments of Physics and Biomedical Engineering Wake Forest School of Medicine Winston-Salem, North Carolina · Summary #12;Irradiation Issues same as for humans · Animal size (nominal L x W x H) · Photon energy (to Beam (high energy) Orthovoltage or Diagnostic X rays (low energy) #12;Isodose Curves Representing

459

Lymphocyte depletion in peripheral blood of gamma irradiated rats  

E-Print Network [OSTI]

38. F. H. Hager, A study of the effect of partial-body irradiation on the early reduction of circulating lymphocytes. (Thesis) Texas AKM University, 1969. 39. G. D'Angelo and M. Lacombe, A practical diluent for electz onic white cell counts. Amer...

Goldin, Eric Michael

1972-01-01T23:59:59.000Z

460

Spatial Pattern Formation in Fused Silica Under UV Irradiation  

E-Print Network [OSTI]

Spatial Pattern Formation in Fused Silica Under UV Irradiation Problem Presenter Leslie Button lenses gradually degrades and ultimately damages these optical components. Corning is a global supplier of optical and ceramic materials across various industries and is particularly interested in this damage

Edwards, David A.

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


461

Vacuum aperture isolator for retroreflection from laser-irradiated target  

DOE Patents [OSTI]

The disclosure is directed to a vacuum aperture isolator for retroreflection of a laser-irradiated target. Within a vacuum chamber are disposed a beam focusing element, a disc having an aperture and a recollimating element. The edge of the focused beam impinges on the edge of the aperture to produce a plasma which refracts any retroreflected light from the laser's target.

Benjamin, Robert F. (Los Alamos, NM); Mitchell, Kenneth B. (Los Alamos, NM)

1980-01-01T23:59:59.000Z

462

The AGR-1 Irradiation -Objectives, Success Criteria and Risk Management  

SciTech Connect (OSTI)

The AGR-1 experiment being conducted by the US Department of Energy Advanced Gas Reactor Fuel Development and Qualification Program (AGR fuel program) will irradiate TRISO-coated particle fuel in compacts under conditions representative of a Very High Temperature Reactor (VHTR) core. The anticipated fuel performance requirements of a prismatic core VHTR significantly exceed established TRISO-coated particle fuel capability in terms of burnup, temperature and fast fluence. AGR-1 is the first in a planned series of eight irradiations leading to the qualification of low enriched uranium coated particle fuel compacts for service in a VHTR, as identified in an overall Technical Program Plan produced at the beginning of the program . The AGR-1 experiment is scheduled for insertion in the Advanced Test Reactor (ATR) in the first quarter of fiscal year 2007 and to be irradiated for a period of up to approximately two and a half years. The irradiation rig, designated a "test train" is designed to provide six independently controlled (for temperature) and monitored (for fission product gas release) capsules containing fuel samples.

James Kendall

2006-06-01T23:59:59.000Z

463

Proton Irradiation Damage Assessment of Carbon Reinforced Composites  

E-Print Network [OSTI]

Proton Irradiation Damage Assessment of Carbon Reinforced Composites: 2-D & 3-D Weaved Structures carbon-carbon composite ATJ Graphite 3D CC composite AGS Beam-on-Target tests show clearly that carbon composites are better absorbers of thermo- mechanical shock. This is attributed to the very low coeff

McDonald, Kirk

464

Post Irradiation Capabilities at the Idaho National Laboratory  

SciTech Connect (OSTI)

The U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) oversees the research, development, and demonstration activities that ensure nuclear energy remains a viable energy option for the United States. Fuel and material development through fabrication, irradiation, and characterization play a significant role in accomplishing the research needed to support nuclear energy. All fuel and material development requires the understanding of irradiation effects on the fuel performance and relies on irradiation experiments ranging from tests aimed at targeted scientific questions to integral effects under representative and prototypic conditions. The DOE recently emphasized a solution-driven, goal-oriented, science-based approach to nuclear energy development. Nuclear power systems and materials were initially developed during the latter half of the 20th century and greatly facilitated by the United States ability and willingness to conduct large-scale experiments. Fifty-two research and test reactors with associated facilities for performing fabrication and pre and post irradiation examinations were constructed at what is now Idaho National Laboratory (INL), another 14 at Oak Ridge National Laboratory (ORNL), and a few more at other national laboratory sites. Building on the scientific advances of the last several decades, our understanding of fundamental nuclear science, improvements in computational platforms, and other tools now enable technological advancements with less reliance on large-scale experimentation.

Schulthess, J.L.

2011-08-01T23:59:59.000Z

465

Post Irradiation Capabilities at the Idaho National Laboratory  

SciTech Connect (OSTI)

The U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) oversees the research, development, and demonstration activities that ensure nuclear energy remains a viable energy option for the United States. Fuel and material development through fabrication, irradiation, and characterization play a significant role in accomplishing the research needed to support nuclear energy. All fuel and material development requires the understanding of irradiation effects on the fuel performance and relies on irradiation experiments ranging from tests aimed at targeted scientific questions to integral effects under representative and prototypic conditions. The DOE recently emphasized a solution-driven, goal-oriented, science-based approach to nuclear energy development. Nuclear power systems and materials were initially developed during the latter half of the 20th century and greatly facilitated by the United States’ ability and willingness to conduct large-scale experiments. Fifty-two research and test reactors with associated facilities for performing fabrication and pre and post irradiation examinations were constructed at what is now Idaho National Laboratory (INL), another 14 at Oak Ridge National Laboratory (ORNL), and a few more at other national laboratory sites. Building on the scientific advances of the last several decades, our understanding of fundamental nuclear science, improvements in computational platforms, and other tools now enable technological advancements with less reliance on large-scale experimentation.

Schulthess, J.L.; Robert D. Mariani; Rory Kennedy; Doug Toomer

2011-08-01T23:59:59.000Z

466

Compressive Strength of Gamma-Irradiated Polymer Concrete  

E-Print Network [OSTI]

Compressive Strength of Gamma-Irradiated Polymer Concrete Gonzalo Marti´nez-Barrera,1,2 Uriel concrete (PC) was developed by using differ- ent concentrations of silica sand as aggregate of Plastics Engineers INTRODUCTION Polymer concrete (PC) is a particulate composite where thermoset resins

North Texas, University of

467

atomic hydrogen irradiation: Topics by E-print Network  

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

hydrogen irradiation First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Synergistic Formation of Radicals...

468

Thermoelastic Generation of Ultrasound by Line-Focused Laser Irradiation  

E-Print Network [OSTI]

Thermoelastic Generation of Ultrasound by Line-Focused Laser Irradiation Irene Arias and Jan D 60208, USA Abstract A two-dimensional theoretical model for the field generated in the thermoelas- tic for the model. Some representative results are presented to illustrate the generated field and provide insight

Huerta, Antonio

469

Evaluating Quality and Palatability Characteristics of Beef Subprimals Treated with Low-dose Irradiation  

E-Print Network [OSTI]

. Paired subprimals were randomly assigned to treated (irradiated) and control (non-irradiated) groups. The treated group was irradiated with a surface dose of 1-1.5 kGy. Following treatment, subprimals were fabricated into thirds and randomly assigned...

Arnold, John

2012-02-14T23:59:59.000Z

470

Dose characterization of the rad source 2400 x-ray irradiator  

E-Print Network [OSTI]

The RS 2400 irradiator has been looked to as a replacement for discontinued gamma irradiators. The RS 2400 has a cylindrical, rather than point, x-ray source, which yields higher dose rates. The irradiator unit allows the user to set the current...

Wagner, Jennifer Ann Koop

2009-05-15T23:59:59.000Z

471

Irradiation Studies of Optical Components CERN, ~ April 15-24, 2005  

E-Print Network [OSTI]

Irradiation Studies of Optical Components 43 2 5 1 CERN, ~ April 15-24, 2005 1 GeV proton beam 4 x, 2005Optical components #12;Irradiation summary ­ transmittance/reflectance measurements Activity right 10 15 proton Irradiation dose: equivalent to 40 pulses of 24 GeV proton beam Received radiation dose

McDonald, Kirk

472

Rapid degradation of CdSe/ZnS colloidal quantum dots exposed to gamma irradiation  

E-Print Network [OSTI]

- grade their optical properties. In this paper, we report on the effects of gamma irradiationRapid degradation of CdSe/ZnS colloidal quantum dots exposed to gamma irradiation Nathan J. Withers of 137 Cs gamma irradiation on photoluminescent properties of CdSe/ZnS colloidal quantum dots

New Mexico, University of

473

Thermally and optically stimulated processes in X-irradiated scheelite type crystals  

E-Print Network [OSTI]

Thermally and optically stimulated processes in X-irradiated scheelite type crystals M. Bohm, R at http://dx.doi.org/10.1051/jphyscol:19806132 #12;THbKMALLY AND OPTICALLY STIMULATED PROCESSES IN X-IRRADIATED and extrinsic) hole and electron centres are created by X-irradiation at liquid nitrogen temperature. Several

Paris-Sud XI, Université de

474

Microscopic mechanisms of laser ablation of organic solids in the thermal and stress confinement irradiation regimes  

E-Print Network [OSTI]

irradiation is defined by the combination of the optical, mechanical and thermodynamic properties irradiation regimes Leonid V. Zhigileia) and Barbara J. Garrisonb) Department of Chemistry, The Pennsylvania confinement regime results in broader velocity distributions in the direction normal to the irradiated surface

Zhigilei, Leonid V.

475

Photorefractive measurements in electron irradiated semi-insulating GaAs  

E-Print Network [OSTI]

. The native and irradiation induced defects have been assessed by electron paramagnetic resonance and optical irradiation induced defects in GaAs, we present results of electron paramagnetic resonance (EPR) and optical1 Photorefractive measurements in electron irradiated semi-insulating GaAs P. Delaye(1), H.J. von

476

Capillary Electrophoresis Separation of Protein Composition of c-Irradiated Food Pathogens Listeria  

E-Print Network [OSTI]

Capillary Electrophoresis Separation of Protein Composition of c-Irradiated Food Pathogens Listeria proteins expression which may be related to the resistance or sensitivity of food pathogens to c-irradiation Composition of c-Irradiated Food Pathogens Listeria monocytogenes and Staphylococcus aureus. PLoS ONE 7(3): e

Paris-Sud XI, Université de

477

Total Solar Irradiance Calibration Transfer Experiment/TIM Frequently Asked Questions  

E-Print Network [OSTI]

TCTE Total Solar Irradiance Calibration Transfer Experiment/TIM Frequently Asked Questions What is the purpose of the TCTE mission? The Total Solar Irradiance Calibration Transfer Experiment (TCTE to monitor changes in solar irradiance at the top of the Earth's atmosphere. TCTE will launch as one of five

Mojzsis, Stephen J.

478

A new, lower value of total solar irradiance: Evidence and climate significance  

E-Print Network [OSTI]

data. TIM's lower solar irradiance value is not a change in the Sun's output, whose variationsA new, lower value of total solar irradiance: Evidence and climate significance Greg Kopp1 14 January 2011. [1] The most accurate value of total solar irradiance during the 2008 solar minimum

479

Irradiation and annealing of p-type silicon carbide  

SciTech Connect (OSTI)

The development of the technology of semiconductor devices based on silicon carbide and the beginning of their industrial manufacture have made increasingly topical studies of the radiation hardness of this material on the one hand and of the proton irradiation to form high-receptivity regions on the other hand. This paper reports on a study of the carrier removal rate (V{sub d}) in p-6H-SiC under irradiation with 8 MeV protons and of the conductivity restoration in radiation- compensated epitaxial layers of various p-type silicon carbide polytypes. V{sub d} was determined by analysis of capacitance-voltage characteristics and from results of Hall effect measurements. It was found that the complete compensation of samples with the initial value of Na - Nd ? 1.5 × 10{sup 18} cm{sup ?3} occurs at an irradiation dose of ?1.1 × 10{sup 16} cm{sup ?2}. It is shown that specific features of the sublimation layer SiC (compared to CVD layers) are clearly manifested upon the gamma and electron irradiation and are hardly noticeable under the proton and neutron irradiation. It was also found that the radiation-induced compensation of SiC is retained after its annealing at ?1000°C. The conductivity is almost completely restored at T ? 1200°C. This character of annealing of the radiation compensation is independent of a silicon carbide polytype and the starting doping level of the epitaxial layer. The complete annealing temperatures considerably exceed the working temperatures of SiC-based devices. It is shown that the radiation compensation is a promising method in the technology of high-temperature devices based on SiC.

Lebedev, Alexander A.; Bogdanova, Elena V.; Grigor'eva, Maria V.; Lebedev, Sergey P. [A.F. Ioffe Physical-Technical Institute, St. Petersburg, 194021 (Russian Federation); Kozlovski, Vitaly V. [St. Petersburg State Polytechnic University, St. Petersburg, 195251 (Russian Federation)

2014-02-21T23:59:59.000Z

480

Microscopic analysis of irradiated AGR-1 coated particle fuel compacts  

SciTech Connect (OSTI)

The AGR-1 experiment involved irradiation of 72 TRISO-coated particle fuel compacts to a peak compact-average burnup of 19.5% FIMA with no in-pile failures observed out of 3 x 105 total particles. Irradiated AGR-1 fuel compacts have been cross-sectioned and analyzed with optical microscopy to characterize kernel, buffer, and coating behavior. Six compacts have been examined, spanning a range of irradiation conditions (burnup, fast fluence, and irradiation temperature) and including all four TRISO coating variations irradiated in the AGR-1 experiment. The cylindrical specimens were sectioned both transversely and longitudinally, then polished to expose from 36 to 79 individual particles near midplane on each mount. The analysis focused primarily on kernel swelling and porosity, buffer densification and fracturing, buffer–IPyC debonding, and fractures in the IPyC and SiC layers. Characteristic morphologies have been identified, 981 particles have been classified, and spatial distributions of particle types have been mapped. No significant spatial patterns were discovered in these cross sections. However, some trends were found between morphological types and certain behavioral aspects. Buffer fractures were found in 23% of the particles, and these fractures often resulted in unconstrained kernel protrusion into the open cavities. Fractured buffers and buffers that stayed bonded to IPyC layers appear related to larger pore size in kernels. Buffer–IPyC interface integrity evidently factored into initiation of rare IPyC fractures. Fractures through part of the SiC layer were found in only four classified particles, all in conjunction with IPyC–SiC debonding. Compiled results suggest that the deliberate coating fabrication variations influenced the frequencies of IPyC fractures and IPyC–SiC debonds.

Scott A. Ploger; Paul A. Demkowicz; John D. Hunn; Jay S. Kehn

2014-05-01T23:59:59.000Z

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


481

Microscopic analysis of irradiated AGR-1 coated particle fuel compacts  

SciTech Connect (OSTI)

The AGR-1 experiment involved irradiation of 72 TRISO-coated particle fuel compacts to a peak burnup of 19.5% FIMA with no in-pile failures observed out of 3×105 total particles. Irradiated AGR-1 fuel compacts have been cross-sectioned and analyzed with optical microscopy to characterize kernel, buffer, and coating behavior. Five compacts have been examined so far, spanning a range of irradiation conditions (burnup, fast fluence, and irradiation temperature) and including all four TRISO coating variations irradiated in the AGR-1 experiment. The cylindrical specimens were sectioned both transversely and longitudinally, then polished to expose between approximately 40-80 individual particles on each mount. The analysis focused primarily on kernel swelling and porosity, buffer densification and fracturing, buffer-IPyC debonding, and fractures in the IPyC and SiC layers. Characteristic morphologies have been identified, over 800 particles have been classified, and spatial distributions of particle types have been mapped. No significant spatial patterns were discovered in these cross sections. However, some trends were found between morphological types and certain behavioral aspects. Buffer fractures were found in approximately 23% of the particles, and these fractures often resulted in unconstrained kernel swelling into the open cavities. Fractured buffers and buffers that stayed bonded to IPyC layers appear related to larger pore size in kernels. Buffer-IPyC interface integrity evidently factored into initiation of rare IPyC fractures. Fractures through part of the SiC layer were found in only three particles, all in conjunction with IPyC-SiC debonding. Compiled results suggest that the deliberate coating fabrication variations influenced the frequencies of IPyC fractures, IPyC-SiC debonds, and SiC fractures.

Scott Ploger; Paul Demkowicz; John Hunn; Robert Morris

2012-10-01T23:59:59.000Z

482

Curved and diffuse interface effects on the nuclear surface tension  

E-Print Network [OSTI]

We redefine the surface tension coefficient for a nuclear Fermi-liquid drop with a finite diffuse layer. Following Gibbs-Tolman concept, we introduce the equimolar radius R_e of sharp surface droplet at which the surface tension is applied and the radius of tension surface R_s which provides the minimum of the surface tension coefficient \\sigma. This procedure allows us to derive both the surface tension and the corresponding curvature correction (Tolman length) correctly for the curved and diffuse interface. We point out that the curvature correction depends significantly on the finite diffuse interface. This fact is missed in traditional nuclear considerations of curvature correction to the surface tension. We show that Tolman's length \\xi is negative for nuclear Fermi-liquid drop. The value of the Tolman length is only slightly sensitive to the Skyrme force parametrization and equals \\xi=-0.36 fm.

V. M. Kolomietz; S. V. Lukyanov; A. I. Sanzhur

2012-01-30T23:59:59.000Z

483

Diffusion Enhancement in Core-softened fluid confined in nanotubes  

E-Print Network [OSTI]

We study the effect of confinement in the dynamical behavior of a core-softened fluid. The fluid is modeled as a two length scales potential. This potential in the bulk reproduces the anomalous behavior observed in the density and in the diffusion of liquid water. A series of $NpT$ Molecular Dynamics simulations for this two length scales fluid confined in a nanotube were performed. We obtain that the diffusion coefficient increases with the increase of the nanotube radius for wide channels as expected for normal fluids. However, for narrow channels, the confinement shows an enhancement in the diffusion coefficient when the nanotube radius decreases. This behavior, observed for water, is explained in the framework of the two length scales potential.

José R. Bordin; Alan B. de Oliveira; Alexandre Diehl; Marcia C. Barbosa

2012-08-05T23:59:59.000Z

484

Phantom cascades: The effect of hidden nodes on information diffusion  

E-Print Network [OSTI]

Research on information diffusion generally assumes complete knowledge of the underlying network. However, in the presence of factors such as increasing privacy awareness, restrictions on application programming interfaces (APIs) and sampling strategies, this assumption rarely holds in the real world which in turn leads to an underestimation of the size of information cascades. In this work we study the effect of hidden network structure on information diffusion processes. We characterise information cascades through activation paths traversing visible and hidden parts of the network. We quantify diffusion estimation error while varying the amount of hidden structure in five empirical and synthetic network datasets and demonstrate the effect of topological properties on this error. Finally, we suggest practical recommendations for practitioners and propose a model to predict the cascade size with minimal information regarding the underlying network.

Belák, Václav; Sala, Alessandra; Morrison, Donn

2015-01-01T23:59:59.000Z

485

Particle production and nonlinear diffusion in relativistic systems  

E-Print Network [OSTI]

The short parton production phase in high-energy heavy-ion collisions is treated analytically as a nonlinear diffusion process. The initial buildup of the rapidity density distributions of produced charged hadrons within tau_p = 0.25 fm/c occurs in three sources during the colored partonic phase. In a two-step approach, the subsequent diffusion in pseudorapidity space during the interaction time of tau_int = 7-10 fm/c (mean duration of the collision) is essentially linear as expressed in the Relativistic Diffusion Model (RDM) which yields excellent agreement with the data at RHIC energies, and allows for predictions at LHC energies. Results for d+Au are discussed in detail.

Georg Wolschin

2008-09-06T23:59:59.000Z

486

Irradiation hardening and loss of ductility of type 316L(N) stainless steel plate material due to neutron-irradiation  

SciTech Connect (OSTI)

Type 316 stainless steel is the primary candidate austenitic structural material for fusion first wall constructions. Here, type 316L(N) stainless steel plate material has been irradiated up to 10 dpa at temperatures of 80, 225, 325, and 425 C in the High Flux Reactor (HFR) of Petten. Tensile tests have been performed in the temperature range from RT to 575 C at a conventional strain rate of 5 {times} 10{sup {minus}4} s{sup {minus}1}. The results of the tensile tests are analyzed in terms of irradiation hardening and loss of ductility due to irradiation. Tensile properties saturate in the early stage (within 0.65 dpa) at the lowest applied irradiation temperature. It is indicated that the most severe degradation of tensile ductility occurs in the temperature range of 275 to 350 C. Comparison with literature data revealed a large scatter in irradiation hardening at irradiation temperatures above 325 C.

Horsten, M.G.; Vries, M.I. de [Netherlands Energy Research Foundation, Petten (Netherlands)

1996-12-31T23:59:59.000Z

487

Evidence of Multi-Process Matrix Diffusion in a Single Fracturefrom a Field Tracer Test  

SciTech Connect (OSTI)

Compared to values inferred from laboratory tests on matrix cores, many field tracer tests in fractured rock have shown enhanced matrix diffusion coefficient values (obtained using a single-process matrix-diffusion model with a homogeneous matrix diffusion coefficient). To investigate this phenomenon, a conceptual model of multi-process matrix diffusion in a single-fracture system was developed. In this model, three matrix diffusion processes of different diffusion rates were assumed to coexist: (1) diffusion into stagnant water and infilling materials within fractures, (2) diffusion into a degraded matrix zone, and (3) further diffusion into an intact matrix zone. The validity of the conceptual model was then demonstrated by analyzing a unique tracer test conducted using a long-time constant-concentration injection. The tracer-test analysis was conducted using a numerical model capable of tracking the multiple matrix-diffusion processes. The analysis showed that in the degraded zone, a diffusion process with an enhanced diffusion rate controlled the steep rising limb and decay-like falling limb in the observed breakthrough curve, whereas in the intact matrix zone, a process involving a lower diffusion rate affected the long-term middle platform of slowly increasing tracer concentration. The different matrix-diffusion-coefficient values revealed from the field tracer test are consistent with the variability of matrix diffusion coefficient measured for rock cores with different degrees of fracture coating at the same site. By comparing to the matrix diffusion coefficient calibrated using single-process matrix diffusion, we demonstrated that this multi-process matrix diffusion may contribute to the enhanced matrix-diffusion-coefficient values for single-fracture systems at the field scale.

Zhou, Quanlin; Liu, Hui-Hai; Bodvarsson, Gudmundur; Molz, Fred J.

2005-06-11T23:59:59.000Z

488

Irradiated Materials Testing Complex (IMTL) The Irradiated Materials Testing Laboratory provides the capability to conduct high temperature  

E-Print Network [OSTI]

provides the capability to conduct high temperature corrosion and stress corrosion cracking of neutron next to a hot cell. This configuration allows us to disconnect the autoclave from its water loop, maneuver it into the hot cell, where the neutron irradiated specimens can be safely mounted

Kamat, Vineet R.

489

Feasibility of gas-phase decontamination of gaseous diffusion equipment  

SciTech Connect (OSTI)

The five buildings at the K-25 Site formerly involved in the gaseous diffusion process contain 5000 gaseous diffusion stages as well as support facilities that are internally contaminated with uranium deposits. The gaseous diffusion facilities located at the Portsmouth Gaseous Diffusion Plant and the Paducah Gaseous Diffusion Plant also contain similar equipment and will eventually close. The decontamination of these facilities will require the most cost-effective technology consistent with the criticality, health physics, industrial hygiene, and environmental concerns; the technology must keep exposures to hazardous substances to levels as low as reasonably achievable (ALARA). This report documents recent laboratory experiments that were conducted to determine the feasibility of gas-phase decontamination of the internal surfaces of the gaseous diffusion equipment that is contaminated with uranium deposits. A gaseous fluorinating agent is used to fluorinate the solid uranium deposits to gaseous uranium hexafluoride (UF{sub 6}), which can be recovered by chemical trapping or freezing. The lab results regarding the feasibility of the gas-phase process are encouraging. These results especially showed promise for a novel decontamination approach called the long-term, low-temperature (LTLT) process. In the LTLT process: The equipment is rendered leak tight, evacuated, leak tested, and pretreated, charged with chlorine trifluoride (ClF{sub 3}) to subatmospheric pressure, left for an extended period, possibly > 4 months, while processing other items. Then the UF{sub 6} and other gases are evacuated. The UF{sub 6} is recovered by chemical trapping. The lab results demonstrated that ClF{sub 3} gas at subatmospheric pressure and at {approx} 75{degree}F is capable of volatilizing heavy deposits of uranyl fluoride from copper metal surfaces sufficiently that the remaining radioactive emissions are below limits.

Munday, E.B.; Simmons, D.W.

1993-02-01T23:59:59.000Z

490

Verification of the integrity of barriers using gas diffusion  

SciTech Connect (OSTI)

In-situ barrier materials and designs are being developed for containment of high risk contamination as an alternative to immediate removal or remediation. The intent of these designs is to prevent the movement of contaminants in either the liquid or vapor phase by long-term containment, essentially buying time until the contaminant depletes naturally or a remediation can be implemented. The integrity of the resultant soil-binder mixture is typically assessed by a number of destructive laboratory tests (leaching, compressive strength, mechanical stability with respect to wetting and freeze-thaw cycles) which as a group are used to infer the likelihood of favorable long-term performance of the barrier. The need exists for a minimally intrusive yet quantifiable methods for assessment of a barrier`s integrity after emplacement, and monitoring of the barrier`s performance over its lifetime. Here, the authors evaluate non-destructive measurements of inert-gas diffusion (specifically, SF{sub 6}) as an indicator of waste-form integrity. The goals of this project are to show that diffusivity can be measured in core samples of soil jet-grouted with Portland cement, validate the experimental method through measurements on samples, and to calculate aqueous diffusivities from a series of diffusion measurements. This study shows that it is practical to measure SF{sub 6} diffusion rates in the laboratory on samples of grout (Portland cement and soil) typical of what might be used in a barrier. Diffusion of SF{sub 6} through grout (Portland cement and soil) is at least an order of magnitude slower than through air. The use of this tracer should be sensitive to the presence of fractures, voids, or other discontinuities in the grout/soil structure. Field-scale measurements should be practical on time-scales of a few days.

Ward, D.B. [SPECTRA Research Inst., Albuquerque, NM (United States); Williams, C.V. [Sandia National Labs., Albuquerque, NM (United States). Environmental Restoration Technologies Dept.

1997-06-01T23:59:59.000Z

491

Characterization of the neutron irradiation system for use in the Low-Dose-Rate Irradiation Facility at Sandia National Laboratories.  

SciTech Connect (OSTI)

The objective of this work was to characterize the neutron irradiation system consisting of americium-241 beryllium (241AmBe) neutron sources placed in a polyethylene shielding for use at Sandia National Laboratories (SNL) Low Dose Rate Irradiation Facility (LDRIF). With a total activity of 0.3 TBq (9 Ci), the source consisted of three recycled 241AmBe sources of different activities that had been combined into a single source. The source in its polyethylene shielding will be used in neutron irradiation testing of components. The characterization of the source-shielding system was necessary to evaluate the radiation environment for future experiments. Characterization of the source was also necessary because the documentation for the three component sources and their relative alignment within the Special Form Capsule (SFC) was inadequate. The system consisting of the source and shielding was modeled using Monte Carlo N-Particle transport code (MCNP). The model was validated by benchmarking it against measurements using multiple techniques. To characterize the radiation fields over the full spatial geometry of the irradiation system, it was necessary to use a number of instruments of varying sensitivities. First, the computed photon radiography assisted in determining orientation of the component sources. With the capsule properly oriented inside the shielding, the neutron spectra were measured using a variety of techniques. A N-probe Microspec and a neutron Bubble Dosimeter Spectrometer (BDS) set were used to characterize the neutron spectra/field in several locations. In the third technique, neutron foil activation was used to ascertain the neutron spectra. A high purity germanium (HPGe) detector was used to characterize the photon spectrum. The experimentally measured spectra and the MCNP results compared well. Once the MCNP model was validated to an adequate level of confidence, parametric analyses was performed on the model to optimize for potential experimental configurations and neutron spectra for component irradiation. The final product of this work is a MCNP model validated by measurements, an overall understanding of neutron irradiation system including photon/neutron transport and effective dose rates throughout the system, and possible experimental configurations for future irradiation of components.

Franco, Manuel,

2014-08-01T23:59:59.000Z

492

Current distribution in systems with anomalous diffusion: renormalisation group approach  

E-Print Network [OSTI]

We investigate the asymptotic properties of the large deviation function of the integrated particle current in systems, in or out of thermal equilibrium, whose dynamics exhibits anomalous diffusion. The physical systems covered by our study include mutually repelling particles with a drift, a driven lattice gas displaying a continuous nonequilibrium phase transition, and particles diffusing in a anisotropic random advective field. It is exemplified how renormalisation group techniques allow for a systematic determination of power laws in the corresponding current large deviation functions. We show that the latter are governed by known universal scaling exponents, specifically, the anomalous dimension of the noise correlators.

Vivien Lecomte; Uwe C. Tauber; Frederic van Wijland

2007-02-01T23:59:59.000Z

493