Powered by Deep Web Technologies
Note: This page contains sample records for the topic "medium medium medium" 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

Amorphous Medium Language  

E-Print Network [OSTI]

Programming reliable behavior on a large mesh network composed of unreliable parts is difficult. Amorphous Medium Language addresses this problem by abstracting robustness and networking issues away from the programmer via ...

Beal, Jacob

2

Liquid chromatographic extraction medium  

DOE Patents [OSTI]

A method and apparatus for extracting strontium and technetium values from biological, industrial and environmental sample solutions using a chromatographic column is described. An extractant medium for the column is prepared by generating a solution of a diluent containing a Crown ether and dispersing the solution on a resin substrate material. The sample solution is highly acidic and is introduced directed to the chromatographic column and strontium or technetium is eluted using deionized water.

Horwitz, E. Philip (Naperville, IL); Dietz, Mark L. (Evanston, IL)

1994-01-01T23:59:59.000Z

3

Liquid chromatographic extraction medium  

DOE Patents [OSTI]

A method and apparatus are disclosed for extracting strontium and technetium values from biological, industrial and environmental sample solutions using a chromatographic column. An extractant medium for the column is prepared by generating a solution of a diluent containing a Crown ether and dispersing the solution on a resin substrate material. The sample solution is highly acidic and is introduced directed to the chromatographic column and strontium or technetium is eluted using deionized water. 1 fig.

Horwitz, E.P.; Dietz, M.L.

1994-09-13T23:59:59.000Z

4

DENSE MEDIUM CYCLONE OPTIMIZATON  

SciTech Connect (OSTI)

Dense medium cyclones (DMCs) are known to be efficient, high-tonnage devices suitable for upgrading particles in the 50 to 0.5 mm size range. This versatile separator, which uses centrifugal forces to enhance the separation of fine particles that cannot be upgraded in static dense medium separators, can be found in most modern coal plants and in a variety of mineral plants treating iron ore, dolomite, diamonds, potash and lead-zinc ores. Due to the high tonnage, a small increase in DMC efficiency can have a large impact on plant profitability. Unfortunately, the knowledge base required to properly design and operate DMCs has been seriously eroded during the past several decades. In an attempt to correct this problem, a set of engineering tools have been developed to allow producers to improve the efficiency of their DMC circuits. These tools include (1) low-cost density tracers that can be used by plant operators to rapidly assess DMC performance, (2) mathematical process models that can be used to predict the influence of changes in operating and design variables on DMC performance, and (3) an expert advisor system that provides plant operators with a user-friendly interface for evaluating, optimizing and trouble-shooting DMC circuits. The field data required to develop these tools was collected by conducting detailed sampling and evaluation programs at several industrial plant sites. These data were used to demonstrate the technical, economic and environmental benefits that can be realized through the application of these engineering tools.

Gerald H. Luttrell; Chris J. Barbee; Peter J. Bethell; Chris J. Wood

2005-06-30T23:59:59.000Z

5

Medium Effects in Parton Distributions  

SciTech Connect (OSTI)

A defining experiment of high-energy physics in the 1980s was that of the EMC collaboration where it was first observed that parton distributions in nuclei are non-trivially related to those in the proton. This result implies that the presence of the nuclear medium plays an important role and an understanding of this from QCD has been an important goal ever since Here we investigate analogous, but technically simpler, effects in QCD and examine how the lowest moment of the pion parton distribution is modified by the presence of a Bose-condensed gas of pions or kaons.

William Detmold, Huey-Wen Lin

2011-12-01T23:59:59.000Z

6

The Interstellar Medium Surrounding the Sun  

E-Print Network [OSTI]

interstellar medium (ISM) suggest an in- homogeneous Galactic environment, with shocks that destroy grainsThe Interstellar Medium Surrounding the Sun Priscilla C. Frisch,1 Seth Redfield,2 and Jonathan D by Annual Reviews. All rights reserved 0066-4146/11/0922-0237$20.00 Keywords interstellar medium

Royer, Dana

7

Sintered composite medium and filter  

DOE Patents [OSTI]

A particulate filter medium is formed of a sintered composite of 0.5 micron diameter quartz fibers and 2 micron diameter stainless steel fibers. A preferred composition is about 40 vol. % quartz and about 60 vol. % stainless steel fibers. The media is sintered at about 1100.degree. C. to bond the stainless steel fibers into a cage network which holds the quartz fibers. High filter efficiency and low flow resistance are provided by the smaller quartz fibers. High strength is provided by the stainless steel fibers. The resulting media has a high efficiency and low pressure drop similar to the standard HEPA media, with tensile strength at least four times greater, and a maximum operating temperature of about 550.degree. C. The invention also includes methods to form the composite media and a HEPA filter utilizing the composite media. The filter media can be used to filter particles in both liquids and gases.

Bergman, Werner (Pleasanton, CA)

1987-01-01T23:59:59.000Z

8

Medium-induced multi-photon radiation  

E-Print Network [OSTI]

We study the spectrum of multi-photon radiation off a fast quark in medium in the BDMPS/ASW approach. We reproduce the medium-induced one-photon radiation spectrum in dipole approximation, and go on to calculate the two-photon radiation in the Moli\\`{e}re limit. We find that in this limit the LPM effect holds for medium-induced two-photon ladder emission.

Hao Ma; Carlos A. Salgado; Konrad Tywoniuk

2011-05-29T23:59:59.000Z

9

Interaction of gravitational waves with an elastic solid medium  

E-Print Network [OSTI]

Contents. 1. Introduction. 2. Kinematics of a Material Medium: Material Representation. 3. Kinematics of a Material Medium: Convected Differentials. 4. Kinematics of a Perfect Elastic Medium. 5. Small Gravitational Perturbations of an Elastic Medium.

B. Carter

2001-02-28T23:59:59.000Z

10

Enrichment of the Intracluster Medium  

E-Print Network [OSTI]

The relevance of galaxies of different luminosity and mass for the chemical enrichment of the intracluster medium (ICM) is analysed. For this purpose, I adopt the composite luminosity function of cluster galaxies from Trentham (1998), which exhibits a significant rise at the very faint end. The model - adopting a universal Salpeter IMF - is calibrated on reproducing the M_Fe/L_tot, M_Fe/M_*, and alpha/Fe ratios observed in clusters. Although the contribution to total luminosity and ICM metals peaks around L* galaxies (M* approx -20), faint objects with M_B>-18 still provide at least 30 per cent of the metals present in the ICM. In consistency with the solar alpha/Fe ratios determined by {ASCA}, the model predicts that 60 per cent of the ICM iron comes from Type Ia supernovae. The predicted slope of the relation between intracluster gas mass and cluster luminosity emerges shallower than the observed one, indicating that the fraction of primordial gas increases with cluster richness.

D. Thomas

1998-11-25T23:59:59.000Z

11

A renewed look at eta' in medium  

E-Print Network [OSTI]

We revisit the question of whether the U_A(1) symmetry is effectively restored in hot and dense medium. In particular, by generalizing the Witten-Veneziano formula to finite temperature, we investigate whether the mass of eta'-meson will change in medium due to the restoration of chiral symmetry.

Youngshin Kwon; Su Houng Lee; Kenji Morita; Gyuri Wolf

2012-04-14T23:59:59.000Z

12

Method to prepare nanoparticles on porous mediums  

DOE Patents [OSTI]

A method to prepare porous medium decorated with nanoparticles involves contacting a suspension of nanoparticles in an ionic liquid with a porous medium such that the particles diffuse into the pores of the medium followed by heating the resulting composition to a temperature equal to or greater than the thermal decomposition temperature of the ionic liquid resulting in the removal of the liquid portion of the suspension. The nanoparticles can be a metal, an alloy, or a metal compound. The resulting compositions can be used as catalysts, sensors, or separators.

Vieth, Gabriel M. (Knoxville, TN) [Knoxville, TN; Dudney, Nancy J. (Oak Ridge, TN) [Oak Ridge, TN; Dai, Sheng (Knoxville, TN) [Knoxville, TN

2010-08-10T23:59:59.000Z

13

Holographic Nucleons in the Nuclear Medium  

E-Print Network [OSTI]

We investigate the nucleon's rest mass and dispersion relation in the nuclear medium which is holographically described by the thermal charged AdS geometry. On this background, the chiral condensate plays an important role to determine the nucleon's mass in both the vacuum and the nuclear medium. It also significantly modifies the nucleon's dispersion relation. The nucleon's mass in the high density regime increases with density as expected, while in the low density regime it slightly decreases. We further study the splitting of the nucleon's masses caused by the isospin interaction with the nuclear medium.

Bum-Hoon Lee; Chanyong Park

2015-03-12T23:59:59.000Z

14

Cognitive Medium Access: Exploration, Exploitation and Competition  

E-Print Network [OSTI]

1 Cognitive Medium Access: Exploration, Exploitation and Competition Lifeng Lai, Hesham El Gamal, Hai Jiang and H. Vincent Poor Abstract-- This paper establishes the equivalence between cognitive cognitive user wishes to opportunistically exploit the availability of empty fre- quency bands

El-Gamal, Hesham

15

Ethanol production using a soy hydrolysate-based medium or a yeast autolysate-based medium  

DOE Patents [OSTI]

This invention presents a method for the production of ethanol that utilizes a soy hydrolysate-based nutrient medium or a yeast autolysate-based medium nutrient medium in conjunction with ethanologenic bacteria and a fermentable sugar for the cost-effective production of ethanol from lignocellulosic biomass. The invention offers several advantages over presently available media for use in ethanol production, including consistent quality, lack of toxins and wide availability.

Ingram, Lonnie O. (Gainesville, FL)

2000-01-01T23:59:59.000Z

16

assessing short medium: Topics by E-print Network  

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

W. 66 The Local Interstellar Medium Astrophysics (arXiv) Summary: The Local Interstellar Medium (LISM) is a unique environment that presents an opportunity to study general...

17

aeruginosa culture medium: Topics by E-print Network  

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

W. 95 The Local Interstellar Medium Astrophysics (arXiv) Summary: The Local Interstellar Medium (LISM) is a unique environment that presents an opportunity to study general...

18

activation depolarizes medium: Topics by E-print Network  

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

W. 173 The Local Interstellar Medium Astrophysics (arXiv) Summary: The Local Interstellar Medium (LISM) is a unique environment that presents an opportunity to study general...

19

Small- and Medium-Size Building Automation and Control System...  

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

Small- and Medium-Size Building Automation and Control System Needs: Scoping Study Small- and Medium-Size Building Automation and Control System Needs: Scoping Study Emerging...

20

Removal of Carbon Tetrachloride from a Layered Porous Medium...  

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

Carbon Tetrachloride from a Layered Porous Medium by Means of Soil Vapor Extraction Enhanced by Desiccation and Water Removal of Carbon Tetrachloride from a Layered Porous Medium...

Note: This page contains sample records for the topic "medium medium medium" 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

Removal of carbon tetrachloride from a layered porous medium...  

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

carbon tetrachloride from a layered porous medium by means of soil vapor extraction enhanced by desiccation and water Removal of carbon tetrachloride from a layered porous medium...

22

Plug-In Hybrid Electric Medium Duty Commercial Fleet Demonstration...  

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

Plug-In Hybrid Electric Medium Duty Commercial Fleet Demonstration and Evaluation Plug-In Hybrid Electric Medium Duty Commercial Fleet Demonstration and Evaluation 2011 DOE...

23

In-Medium Modifications of Hadron Properties  

E-Print Network [OSTI]

The in-medium modifications of hadron properties are briefly discussed. We restrict the discussion to the lattice QCD calculations for the hadron masses, screening masses, decay constants and wave functions. We review the progress made so far and describe how to broaden its horizon.

A. Tawfik

2006-03-22T23:59:59.000Z

24

Medium-fi EvaluationMedium-fi PrototypesMedium-fi DesignLow-fi EvaluationLow-fi Prototypes What is Aphasia?  

E-Print Network [OSTI]

Medium-fi EvaluationMedium-fi PrototypesMedium-fi DesignLow-fi EvaluationLow-fi Prototypes What Cycle Investigated ability of existing technologies to fulfill needs. Extra time is needed to ensure. Evaluated with two participants. One had aphasia as a result of a brain tumour and the other as a result

Findlater, Leah

25

Physical vacuum is a special superfluid medium  

E-Print Network [OSTI]

The Navier-Stokes equation contains two terms which have been subjected to slight modification: (a) the viscosity term depends of time (the viscosity in average on time is zero, but its variance is non-zero); (b) the pressure gradient contains an added term describing the quantum entropy gradient multiplied by the pressure. Owing to these modifications, the Navier-Stokes equation can be reduced to the Schr\\"odinger equation describing behavior of a particle into the vacuum being as a superfluid medium. Vortex structures arising in this medium show infinitely long life owing to zeroth average viscosity. The non-zero variance describes exchange of the vortex energy with zero-point energy of the vacuum. Radius of the vortex trembles around some average value. This observation sheds the light to the Zitterbewegung phenomenon. The long-lived vortex has a non-zero core where the vortex velocity vanishes.

Sbitnev, Valeriy I

2015-01-01T23:59:59.000Z

26

Brownian motor in a granular medium  

E-Print Network [OSTI]

In this work we experimentally study the behavior of a freely-rotating asymmetric probe immersed in a vibrated granular medium. For a wide variety of vibration conditions the probe exhibits a steady rotation whose direction is constant with respect to the asymmetry. By changing the vibration amplitude and by filtering the noise in different frequency bands we show that the velocity of rotation does not depend only on the RMS acceleration $\\Gamma$, but also on the amount of energy provided to two separate frequency bands which are revealed to be important for the dynamics of the granular medium: the first band governs the transfer of energy from the grains to the probe, and the second affects the dynamics by altering the viscosity of the vibro-fluidized material.

Riccardo Balzan; Fergal Dalton; Vittorio Loreto; Alberto Petri; Giorgio Pontuale

2009-09-21T23:59:59.000Z

27

Electromagnetic Radiation and in-Medium Effects  

E-Print Network [OSTI]

The theory of thermal photon and dilepton emission from a hot and dense hadronic gas, as well as from the Quark-Gluon Plasma, is reviewed in the context of extracting in-medium properties of the matter constituents. In phenomenological applications to ultrarelativistic heavy-ion collisions we focus on recent photon and dilepton spectra as measured by WA98 and CERES/NA45, respectively, at CERN-SPS energies.

Ralf Rapp

2005-03-14T23:59:59.000Z

28

Screening masses in thermal and dense medium  

E-Print Network [OSTI]

Screening masses of different hadronic states are studied in thermal and dense medium on lattice. It has been found that screening masses increase with the temperature. In deconfinement phase, chemical potential enhances the screening masses. We use the normalization with respect to lowest Matsubara frequency to characterize dissolving of hadronic bound states at high temperatures. It has been found that different hadronic states have different dissolving temperatures and their survivals are considerably improved at finite chemical potentials.

A. Tawfik

2006-05-29T23:59:59.000Z

29

Exploring medium effects on the nuclear force  

SciTech Connect (OSTI)

This STI product contains a description of results from theoretical studies in nuclear physics. The goal is a systematic investigation of the nuclear force in the nuclear medium. The problems addressed are: density-dependent effective interactions as seen through proton-nucleus reactions, nuclear matter with unequal densities of protons and neutrons, applications to asymmetric nuclei through predictions of neutron radii and neutron skins.

F. Sammarruca

2004-04-18T23:59:59.000Z

30

Cosmic Minivoids in the Intergalactic Medium  

E-Print Network [OSTI]

The Gunn-Peterson effect, absorption of Lya photons by a homogeneous component of the intergalactic medium (IGM), potentially provides a test of Big Bang Nucleosynthesis (BBN). With a lower limit on the UV radiation field estimated from the contribution due to QSOs, a measurement of the Lya opacity of the intergalactic medium would permit the derivation of a lower bound to the baryonic density of the universe. The effect, however, has continually eluded a convincing detection, both in HI and HeII, despite extensive searches. Recent cosmological hydrodynamical simulations of structure formation in the intergalactic medium suggest an explanation for its absence. In a Cold Dark Matter dominated cosmology, the fragmentation of the baryons is nearly complete, leaving a negligible remnant to comprise a smoothly distributed component. The fragmentation extends even into regions that are underdense, where it gives rise to most of the optically thin HI systems and nearly all of the HeII systems, both thin and saturated. The result is a Lya opacity from a smooth IGM that is suppressed by over two orders of magnitude from the BBN value.

Avery Meiksin

1996-11-01T23:59:59.000Z

31

Wave scattering by small particles in a medium  

E-Print Network [OSTI]

Wave scattering is considered in a medium in which many small particles are embedded. Equations for the effective field in the medium are derived when the number of particles tends to infinity.

A. G. Ramm

2007-02-14T23:59:59.000Z

32

Light Vector Mesons in the Nuclear Medium  

SciTech Connect (OSTI)

The light vector mesons ($\\rho$, $\\omega$, and $\\phi$) were produced in deuterium, carbon, titanium, and iron targets in a search for possible in-medium modifications to the properties of the $\\rho$ meson at normal nuclear densities and zero temperature. The vector mesons were detected with the CEBAF Large Acceptance Spectrometer (CLAS) via their decays to $e^{+}e^{-}$. The rare leptonic decay was chosen to reduce final-state interactions. A combinatorial background was subtracted from the invariant mass spectra using a well-established event-mixing technique. The $\\rho$ meson mass spectrum was extracted after the $\\omega$ and $\\phi$ signals were removed in a nearly model-independent way. Comparisons were made between the $\\rho$ mass spectra from the heavy targets ($A > 2$) with the mass spectrum extracted from the deuterium target. With respect to the $\\rho$-meson mass, we obtain a small shift compatible with zero. Also, we measure widths consistent with standard nuclear many-body eff

Wood, Michael; Nasseripour, Rakhsha; Weygand, Dennis; Djalali, Chaden; Tur, Clarisse; Mosel, Ulrich; Muehlich, Pascal; Adams, Gary; Amaryan, Moscov; Amaryan, Moskov; Ambrozewicz, Pawel; Anghinolfi, Marco; Asryan, Gegham; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, James; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Carnahan, Bryan; Casey, Liam; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Crabb, Donald; Crannell, Hall; Crede, Volker; Cummings, John; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dharmawardane, Kahanawita; Dickson, Richard; Dodge, Gail; Doughty, David; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Feldman, Gerald; Feuerbach, Robert; Fradi, Ahmed; Funsten, Herbert; Garcon, Michel; Gavalian, Gagik; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gordon, Christopher; Gothe, Ralf; Griffioen, Keith; Guidal, Michel; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hakobyan, Hayk; Hakobyan, Rafael; Hanretty, Charles; Hardie, John; Hassall, Neil; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Kellie, James; Khandaker, Mahbubul; Khetarpal, Puneet; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klimenko, Alexei; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, David; Li, Ji; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Prok, Yelena; Protopopescu, Dan; Raue, Brian; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Ronchetti, Federico; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinsky, Aleksey; Stepanyan, Stepan; Stepanyan, Samuel; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tedeschi, David; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Todor, Luminita; Ungaro, Maurizio; Vineyard, Michael; Vlassov, Alexander; Watts, Daniel; Weinstein, Lawrence; Williams, Michael; Wolin, Elliott; Yegneswaran, Amrit; Zana, Lorenzo; Zhang, Bin; Zhang, Jixie; Zhao, Bo; Zhao, Zhiwen

2008-07-01T23:59:59.000Z

33

Orthopositronium-orthopositronium scattering at medium energies  

SciTech Connect (OSTI)

The scattering of ortho-positronium (o-Ps) atoms has been investigated using the first Born approximation (FBA) and Born-Oppenheimer (B-O) model at medium energies. The angle integrated total elastic cross sections of o-Ps-o-Ps scattering have been reported. Apart from this, the inelastic cross sections for discrete excitations (principal quantum number, n{<=}3) of the single and both the Ps atoms as well as single and double Ps atom ionization have also been obtained. We have also predicted the total cross section of o-Ps-o-Ps scattering by adding all these partial cross sections. The first Born and B-O scattering amplitudes have also been evaluated using partial wave technique. It has been noticed that odd values of the partial wave B-O amplitude vanishes for even parity transitions and vice versa. To the best of our knowledge, this feature has not been noticed for other systems.

Chakraborty, Sumana; Ghosh, A.S. [Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700 032 (India); Kumari, Kiran [Department of Physics, R N College, Hajipur (Vaishali), B R A Bihar University, Muzaffarpur, Bihar (India)

2005-08-15T23:59:59.000Z

34

Erosion dynamics of a wet granular medium  

E-Print Network [OSTI]

Liquid may give strong cohesion properties to a granular medium, and confer a solid-like behavior. We study the erosion of a fixed circular aggregate of wet granular matter subjected to a flow of dry grains inside a half-filled rotating drum. During the rotation, the dry grains flow around the fixed obstacle. We show that its diameter decreases linearly with time for low liquid content, as wet grains are pulled-out of the aggregate. This erosion phenomenon is governed by the properties of the liquids. The erosion rate decreases exponentially with the surface tension while it depends on the viscosity to the power -1. We propose a model based on the force fluctuations arising inside the flow, explaining both dependencies: the capillary force acts as a threshold and the viscosity controls the erosion time scale. We also provide experiments using different flowing grains confirming our model.

Gautier Lefebvre; Pierre Jop

2014-12-08T23:59:59.000Z

35

Double hadron leptoproduction in the nuclear medium  

E-Print Network [OSTI]

First measurement of double-hadron production in deep-inelastic scattering has been measured with the HERMES spectrometer at HERA using a 27.6 GeV positron beam with deuterium, nitrogen, krypton and xenon targets. The influence of the nuclear medium on the ratio of double-hadron to single-hadron yields has been investigated. Nuclear effects are clearly observed but with substantially smaller magnitude and reduced $A$-dependence compared to previously measured single-hadron multiplicity ratios. The data are in fair agreement with models based on partonic or pre-hadronic energy loss, while they seem to rule out a pure absorptive treatment of the final state interactions. Thus, the double-hadron ratio provides an additional tool for studying modifications of hadronization in nuclear matter.

Airapetian, A; Akopov, Z; Amarian, M; Andrus, A; Aschenauer, E C; Augustyniak, W; Avakian, R; Avetisian, A; Avetissian, E; Bailey, P; Belostotskii, S; Bianchi, N; Blok, H P; Böttcher, Helmut B; Borisov, A; Borysenko, A; Brüll, A; Bryzgalov, V; Capiluppi, M; Capitani, G P; Ciullo, G; Contalbrigo, M; Dalpiaz, P F; Deconinck, W; De Leo, R; Demey, M; De Nardo, L; De Sanctis, E; Devitsin, E G; Diefenthaler, M; Di Nezza, P; Dreschler, J; Düren, M; Ehrenfried, M; Elalaoui-Moulay, A; Elbakian, G; Ellinghaus, F; Elschenbroich, U; Fabbri, R; Fantoni, A; Felawka, L; Frullani, S; Funel, A; Gapienko, G; Gapienko, V; Garibaldi, F; Garrow, K; Gavrilov, G; Karibian, V; Giordano, F; Grebenyuk, O; Gregor, I M; Griffioen, K; Guler, H; Hadjidakis, C; Hartig, M; Hasch, D; Hasegawa, T; Hesselink, W H A; Hillenbrand, A; Hoek, M; Holler, Y; Hommez, B; Hristova, I; Iarygin, G; Ivanilov, A; Izotov, A; Jackson, H E; Jgoun, A; Kaiser, R; Keri, T; Kinney, E; Kiselev, A; Kobayashi, T; Kopytin, M; Korotkov, V; Kozlov, V; Krauss, B; Kravchenko, P; Krivokhizhin, V G; Lagamba, L; Lapikas, L; Lenisa, P; Liebing, P; Linden-Levy, L A; Lorenzon, W; Lü, J; Lu, S; Ma, B Q; Maiheu, B; Makins, N C R; Mao, Y; Marianski, B; Marukyan, H; Masoli, F; Mexner, V; Meyners, N; Michler, T; Miklukho, O; Miller, C A; Miyachi, Y; Muccifora, V; Murray, M; Nagaitsev, A; Nappi, E; Naryshkin, Yu; Negodaev, M; Nowak, Wolf-Dieter; Ohsuga, H; Osborne, A; Perez-Benito, R; Pickert, N; Raithel, M; Reggiani, D; Reimer, P E; Reischl, A; Reolon, A R; Riedl, C; Rith, K; Rosner, G; Rostomyan, A; Rubacek, L; Rubin, J; Ryckbosch, D; Salomatin, Y; Sanjiev, I; Savin, I; Schäfer, A; Schnell, G; Schüler, K P; Seele, J; Seidl, R; Seitz, B; Shearer, C; Shibata, T A; Shutov, V; Sinram, K; Stancari, M; Statera, M; Steffens, E; Steijger, J J M; Stenzel, H; Stewart, J; Stinzing, F; Streit, J; Tait, P; Tanaka, H; Taroian, S P; Tchuiko, B; Terkulov, A R; Trzcinski, A; Tytgat, M; Vandenbroucke, A; Van der Nat, P B; van der Steenhoven, G; Van Haarlem, Y; Veretennikov, D; Vikhrov, V; Vogel, C; Wang, S; Ye, Y; Ye, Z; Yen, S; Zihlmann, B; Zupranski, P

2006-01-01T23:59:59.000Z

36

Optimizing Medium Baseline Reactor Neutrino Experiments  

E-Print Network [OSTI]

10 years from now medium baseline reactor neutrino experiments will attempt to determine the neutrino mass hierarchy from the observed antineutrino spectra. In this letter we present the results of more than four million detailed simulations of such experiments, studying the dependence of the probability of successfully determining the hierarchy upon the analysis method, the neutrino mass matrix parameters, reactor flux models and, in particular, combinations of baselines. We show that the strong dependence of the hierarchy determination upon mass differences and flux models found by Qian et al. results from a spurious dependence of the Fourier analysis upon the high energy tail of the reactor spectrum which can be removed by using a weighted Fourier transform. Such experiments necessarily use flux from multiple reactors at distinct baselines, smearing the oscillation signal and thus impeding the determination of the hierarchy. Using the results of our simulations, we determine the optimal baselines and corre...

Ciuffoli, Emilio; Zhang, Xinmin

2013-01-01T23:59:59.000Z

37

On the Virial Theorem for Interstellar Medium  

SciTech Connect (OSTI)

An attempt has been made to derive a version of the virial integral that would describe average properties of the interstellar medium (ISM). It is suggested to eliminate the (large) contribution of stellar matter by introducing 'exclusion zones' surrounding stars. Such an approach leads to the appearance of several types of additional surface integrals in the general expression. Their contribution depends on the rate of energy and matter exchange between the stars and ISM. If this exchange is weak, one can obtain a desired virial integral for ISM. However, the presence of intermittent large-scale energetic events significantly constrains the applicability of the virial theorem. If valid, the derived virial integral is dominated by cold molecular/atomic clouds, with only minor contribution of the global magnetic field and low-density warm part.

Ryutov, D

2007-09-24T23:59:59.000Z

38

Guidelines and Toolkits for Urban Transport Development in Medium...  

Open Energy Info (EERE)

practitioners in states and municipal governments who are concerned with urban transport development in medium-sized cities in India. In addition, officials within the central...

39

acid medium application: Topics by E-print Network  

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

University - TxSpace Summary: substrate and their catalytic function takes place in acid medium. This harsh environment causes an undesired reaction, which is the dissolution of...

40

acid aqueous medium: Topics by E-print Network  

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

transfer radical polymerization technique ... Yao, Jia 3 Ultrasonic measurement of porous medium in an aqueous environment Texas A&M University - TxSpace Summary: August 1995 Major...

Note: This page contains sample records for the topic "medium medium medium" 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

acidic aqueous medium: Topics by E-print Network  

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

transfer radical polymerization technique ... Yao, Jia 3 Ultrasonic measurement of porous medium in an aqueous environment Texas A&M University - TxSpace Summary: August 1995 Major...

42

Plug-In Hybrid Electric Medium Duty Commercial Fleet Demonstration...  

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

rravt068vssmiyasato2011o .pdf More Documents & Publications SCAQMD:Plug-In Hybrid Electric Medium-Duty Commercial Fleet Demonstration and Evaluation Plug-In Hybrid Electric...

43

Optical quantum swapping in a coherent atomic medium  

E-Print Network [OSTI]

We propose to realize a passive optical quantum swapping device which allows for the exchange of the quantum fluctuations of two bright optical fields interacting with a coherent atomic medium in an optical cavity. The device is based on a quantum interference process between the fields within the cavity bandwidth arising from coherent population trapping in the atomic medium.

Aurelien Dantan

2011-10-03T23:59:59.000Z

44

Ray Theory for a Locally Layered Random Medium G. Papanicolaou  

E-Print Network [OSTI]

variations in the medium parameters. The pulse is generated by a point source and the medium is modeled the source and the point of observation. The ray is determined by high frequency asymptotics (geometrical is motivated by wave propagation in sedimentary rock. Here the sedimentary cycles produce structures

Papanicolaou, George C.

45

Invariant measures for a stochastic porous medium equation  

E-Print Network [OSTI]

Invariant measures for a stochastic porous medium equation Giuseppe Da Prato (Scuola Normale AMS :76S05,35J25, 37L40 . 1 Introduction The porous medium equation X t = (Xm ), m N, (1 Brownian motion in H and C is a positive definite bounded operator on H of trace class. To be more concrete

Röckner, Michael

46

BUSINESS CONTINUITY PLANNING RESOURCES FOR SMALL-AND MEDIUM-  

E-Print Network [OSTI]

BUSINESS CONTINUITY PLANNING RESOURCES FOR SMALL- AND MEDIUM- SIZED BUSINESSES May 2010 Prepared and supported by the Northwest Regional Technology Center for Homeland Security Business Continuity Planning Resources for Small- and Medium- Sized Businesses KS Judd AM Lesperance May 14, 2010 #12;DISCLAIMER

47

Open bottom mesons in hot asymmetric hadronic medium  

E-Print Network [OSTI]

The in-medium masses and optical potentials of $B$ and ${\\bar B}$ mesons are studied in an isospin asymmetric, strange, hot and dense hadronic environment using a chiral effective model. The chiral $SU(3)$ model originally designed for the light quark sector, is generalized to include the heavy quark sector ($c$ and $b$) to derive the interactions of the $B$ and $\\bar B$ mesons with the light hadrons. Due to large mass of bottom quark, we use only the empirical form of these interactions for the desired purpose, while treating the bottom degrees of freedom to be frozen in the medium. Hence, all medium effects are due to the in-medium interaction of the light quark content of these open-bottom mesons. Both $B$ and $\\bar B$ mesons are found to experience net attractive interactions in the medium, leading to lowering of their masses in the medium. The mass degeneracy of particles and antiparticles, ($B^+$, $B^-$) as well as ($B^0$, ${\\bar B}^0$), is observed to be broken in the medium, due to equal and opposite contributions from a vectorial Weinberg-Tomozawa interaction term. Addition of hyperons to the medium lowers further the in-medium mass for each of these four mesons, while a non-zero isospin asymmetry is observed to break the approximate mass degeneracy of each pair of isospin doublets. These medium effects are found to be strongly density dependent, and bear a considerably weaker temperature dependence. The results obtained in the present investigation are compared to predictions from the quark-meson coupling model, heavy meson effective theory, and the QCD Sum Rule approach.

Divakar Pathak; Amruta Mishra

2014-09-02T23:59:59.000Z

48

Electromagnetic field quantization in a linear dielectric medium  

E-Print Network [OSTI]

By modeling a dielectric medium with two independent reservoirs, i.e., electric and magnetic reservoirs, the electromagnetic field is quantized in a linear dielectric medium consistently. A Hamiltonian is proposed from which using the Heisenberg equations, not only the Maxwell equations but also the structural equations can be obtained. Using the Laplace transformation, the wave equation for the electromagnetic vector potential is solved in the case of a homogeneous dielectric medium. Some examples are considered showing the applicability of the model to both absorptive and nonabsorptive dielectrics.

F. Kheirandish; M. Amooshahi

2005-11-13T23:59:59.000Z

49

Electromagnetic radiation in a time-varying background medium  

E-Print Network [OSTI]

Analytical solutions are presented for the electromagnetic radiation by an arbitrary pulsed source into a homogeneous time-varying background medium. In the constant-impedance case an explicit radiation formula is obtained for the synchronous permittivity and permeability described by any positive function of time. As might be expected, such a medium introduces significant spectral shifts and spatio-temporal modulation, which are analized here for the linear and exponential time-variations of the medium parameters. In the varying-impedance case the solution is obtained for the fourth-order polynomial time-dependence of the permittivity. In addition to the spectral shifts and modulation this spatially homogeneous medium scatters the field introducing causal echoes at the receiver location.

Budko, Neil V

2009-01-01T23:59:59.000Z

50

aqueous medium formacion: Topics by E-print Network  

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

19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Ultrasonic measurement of porous medium in an aqueous environment Texas A&M University - TxSpace Summary: August 1995 Major...

51

aqueous medium viewing: Topics by E-print Network  

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

19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Ultrasonic measurement of porous medium in an aqueous environment Texas A&M University - TxSpace Summary: August 1995 Major...

52

aqueous alkaline medium: Topics by E-print Network  

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

which is essential for the formation Sahai, Nita 2 Ultrasonic measurement of porous medium in an aqueous environment Texas A&M University - TxSpace Summary: August 1995 Major...

53

Multiphase turbulent interstellar medium: some recent results from radio astronomy  

E-Print Network [OSTI]

The radio frequency 1.4 GHz transition of the atomic hydrogen is one of the important tracers of the diffuse neutral interstellar medium. Radio astronomical observations of this transition, using either a single dish telescope or an array interferometer, reveal different properties of the interstellar medium. Such observations are particularly useful to study the multiphase nature and turbulence in the interstellar gas. Observations with multiple radio telescopes have recently been used to study these two closely related aspects in greater detail. Using various observational techniques, the density and the velocity fluctuations in the Galactic interstellar medium was found to have a Kolmogorov-like power law power spectra. The observed power law scaling of the turbulent velocity dispersion with the length scale can be used to derive the true temperature distribution of the medium. Observations from a large ongoing atomic hydrogen absorption line survey have also been used to study the distribution of gas at d...

Roy, Nirupam

2015-01-01T23:59:59.000Z

54

Green Radio Communications in a Heterogeneous Wireless Medium  

E-Print Network [OSTI]

1 Green Radio Communications in a Heterogeneous Wireless Medium Muhammad Ismail and Weihua Zhuang wireless communication networks. Such energy efficient solutions are referred to as green communication efficient wireless communication networks, due to environmental, financial, and quality

Zhuang, Weihua

55

Structure functions of free and in-medium nucleons  

SciTech Connect (OSTI)

Spin-dependent quark light-cone momentum distributions are calculated for a nucleon in the nuclear medium. We utilize a modified NJL model where the nucleon is described as a composite quark-diquark state. Scalar and vector mean fields are incorporated in the nuclear medium and these fields couple to the confined quarks in the nucleon. The effect of these fields on the spin-dependent distributions is investigated. Our results for the ''spin-dependent EMC effect'' are also discussed.

Ian Cloet; W. Bentz; Anthony Thomas

2005-04-01T23:59:59.000Z

56

Ultimate disposal of low and medium radioactive waste in France  

SciTech Connect (OSTI)

The National Radioactive Waste Management Agency (ANDRA) has been entrusted with the long-term management of radioactive waste. This paper presents the methodology of safety assessment used by ANDRA for a land disposal facility of radioactive waste with short or medium half-life and with low or medium specific activity. This methodology was used in the design of ``the Centre de stockage de l`Aube``.

Ringeard, C. [National Radioactive Waste Management Agency, Fontenay aux Roses (France). Environmental, Safety, Quality Dept.

1993-12-31T23:59:59.000Z

57

E-Print Network 3.0 - alkaline medium peliculas Sample Search...  

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

rate: medium Texture: medium Foliage Leaf arrangement: alternate (Fig... requirement: tree grows in full sun Soil tolerances: clay; loam; sand; slightly alkaline; acidic;...

58

Biofuel Boundaries: Estimating the Medium-Term Supply Potential of Domestic Biofuels  

E-Print Network [OSTI]

Biofuel Boundaries: Estimating the Medium-Term SupplyAugust 22, 2007 Biofuel Boundaries: Estimating the Medium-significant amount of liquid biofuel (equivalent to 30-100%

Jones, Andrew; O'Hare, Michael; Farrell, Alexander

2007-01-01T23:59:59.000Z

59

Automated Demand Response Technology Demonstration Project for Small and Medium Commercial Buildings  

E-Print Network [OSTI]

Demand Response for Small Commercial Buildings.   Lawrence small?medium buildings’ roles in demand response  efforts.  demand response for small? medium commercial buildings 

Page, Janie

2012-01-01T23:59:59.000Z

60

Medium Modifications of Hadron Properties and Partonic Processes  

SciTech Connect (OSTI)

Chiral symmetry is one of the most fundamental symmetries in QCD. It is closely connected to hadron properties in the nuclear medium via the reduction of the quark condensate , manifesting the partial restoration of chiral symmetry. To better understand this important issue, a number of Jefferson Lab experiments over the past decade have focused on understanding properties of mesons and nucleons in the nuclear medium, often benefiting from the high polarization and luminosity of the CEBAF accelerator. In particular, a novel, accurate, polarization transfer measurement technique revealed for the first time a strong indication that the bound proton electromagnetic form factors in 4He may be modified compared to those in the vacuum. Second, the photoproduction of vector mesons on various nuclei has been measured via their decay to e+e- to study possible in-medium effects on the properties of the rho meson. In this experiment, no significant mass shift and some broadening consistent with expected collisional broadening for the rho meson has been observed, providing tight constraints on model calculations. Finally, processes involving in-medium parton propagation have been studied. The medium modifications of the quark fragmentation functions have been extracted with much higher statistical accuracy than previously possible.

W. K. Brooks, S. Strauch, K. Tsushima

2011-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Quantum-mechanical description of in-medium fragmentation  

E-Print Network [OSTI]

We present a quantum-mechanical description of quark-hadron fragmentation in a nuclear environment. It employs the path-integral formulation of quantum mechanics, which takes care of all phases and interferences, and which contains all relevant time scales, like production, coherence, formation, etc. The cross section includes the probability of pre-hadron (colorless dipole) production both inside and outside the medium. Moreover, it also includes inside-outside production, which is a typical quantum-mechanical interference effect (like twin-slit electron propagation). We observe a substantial suppression caused by the medium, even if the pre-hadron is produced outside the medium and no energy loss is involved. This important source of suppression is missed in the usual energy-loss scenario interpreting the effect of jet quenching observed in heavy ion collisions. This may be one of the reasons of a too large gluon density, reported by such analyzes.

B. Z. Kopeliovich; H. -J. Pirner; I. K. Potashnikova; Ivan Schmidt; A. V. Tarasov; O. O. Voskresenskaya

2008-09-27T23:59:59.000Z

62

Gamma-ray burst interaction with dense interstellar medium  

E-Print Network [OSTI]

Interaction of cosmological gamma ray burst radiation with the dense interstellar medium of host galaxy is considered. Gas dynamical motion of interstellar medium driven by gamma ray burst is investigated in 2D approximation for different initial density distributions of host galaxy matter and different total energy of gamma ray burst. The maximum velocity of motion of interstellar medium is $1.8\\cdot10^4$ km/s. Light curves of gamma ray burst afterglow are calculated for set of non homogeneous density, distribution gamma ray burst total energy, and different viewing angles. Spectra of gamma ray burst afterglow are modeled taking into account conversion of hard photons (soft X-ray, hard UV) to soft UV and optics photons.

Maxim Barkov; Gennady Bisnovatyi-Kogan

2004-10-07T23:59:59.000Z

63

Nucleon Electromagnetic Form Factors: Free Space and Medium Modifications  

SciTech Connect (OSTI)

We review recent developments in the study of electromagnetic form factors of the nucleon, both in free space and in the nuclear medium. For the free nucleon case, we discuss the ratio of electric to magnetic proton form factors, and the influence of two-photon exchange on the form factor extraction. For the bound nucleon, we examine the implications of the small but non-zero modification of proton form factors in the nuclear medium suggested by recent data on polarized proton knockout reactions off He-4, and discuss constraints which it could place on models of the nuclear EMC effect.

Wally Melnitchouk

2003-10-01T23:59:59.000Z

64

Energy trapping and shock disintegration in a composite granular medium  

E-Print Network [OSTI]

Granular materials demonstrate a strongly nonlinear behavior influencing the wave propagation in the medium. We report the first experimental observation of impulse energy confinement and the resultant disintegration of shock and solitary waves. The medium consists of alternating ensambles of high-modulus vs orders of magnitude lower modulus chains of different masses. The trapped energy is contained within the "softer" portions of the composite chain and is slowly released in the form of weak, separated pulses over an extended period of time. This effect is enhanced by using a specific group assembly and superimposed force.

C. Daraio; V. F. Nesterenko; E. B. Herbold; S. Jin

2005-09-24T23:59:59.000Z

65

CARIBBEAN SEACRUISE IN LUXURY ABOARD CRYSTAL SERENITY BEST MEDIUM  

E-Print Network [OSTI]

CARIBBEAN SEACRUISE IN LUXURY ABOARD CRYSTAL SERENITY WORLD'S BEST MEDIUM CRUISE LINE SIX and brilliantly colored colonial architecture -- this forms the backdrop for our Cruise the Caribbean Sea program at the Caribbean's many offerings, from picturesque lagoons to quaint towns to bustling beaches. Experience

Spence, Harlan Ernest

66

Medium Term Planning & Scheduling under Uncertainty for BP Chemicals  

E-Print Network [OSTI]

for PTA PX. From crude oil to PTA From crude oil to PX Production Chains: Products & Applications Models for planning medium term operations Monthly production Inventory targets What proportion of demand should be satisfied from which inventory location ? Types of businesses: PX PTA Deterministic model represents: Global

Grossmann, Ignacio E.

67

ENSEMBLE RE-FORECASTING : IMPROVING MEDIUM-RANGE FORECAST SKILL  

E-Print Network [OSTI]

5.5 ENSEMBLE RE-FORECASTING : IMPROVING MEDIUM-RANGE FORECAST SKILL USING RETROSPECTIVE FORECASTS, Colorado 1. INTRODUCTION Improving weather forecasts is a primary goal of the U.S. National Oceanic predictions has been to improve the accuracy of the numerical forecast models. Much effort has been expended

Hamill, Tom

68

Model of innovation transfer in small and medium enterprises (SME)  

E-Print Network [OSTI]

Model of innovation transfer in small and medium enterprises (SME) Justyna Patalas-Maliszewska1 society, governments and entrepreneurs. In this paper the concept of innovation transfer in SME based of innovation transfer - based on correlations between innovation level in the enterprise sector SME

69

CalHEAT Research and Market Transformation Roadmap for Medium  

E-Print Network [OSTI]

- 8 Work Trucks Work Site Support Tractors - Short Haul/ Regional Class 2b/3 vans/pickup s Class 3 - 8CalHEAT Research and Market Transformation Roadmap for Medium and Heavy Duty Trucks Delivering President CALSTART #12;California Hybrid, Efficient and Advanced Truck Research Center What is Cal

California at Davis, University of

70

FLAME SURFACE DENSITIES IN PREMIXED COMBUSTION AT MEDIUM TO HIGH  

E-Print Network [OSTI]

premixed combustion diagrams. Small-scale transport of heat and species may be more important and chemistryFLAME SURFACE DENSITIES IN PREMIXED COMBUSTION AT MEDIUM TO HIGH TURBULENCE INTENSITIES O¨ MER L in turbulent premixed propane= air flames were determined experimentally. The instantaneous flame fronts were

Gülder, �mer L.

71

The Solar Wind and Its Interaction with the Interstellar Medium  

E-Print Network [OSTI]

outward through the solar system and interacts with the interstellar neutrals which slow and heat the wind. The arrows in the top panel show the flow of the solar wind and the interstellar J. D. Richardson CenterThe Solar Wind and Its Interaction with the Interstellar Medium John D. Richardson Abstract

Richardson, John

72

Probabilistic picture of in-medium jet evolution  

E-Print Network [OSTI]

We briefly discuss the recently developed probabilistic picture for in-medium jet evolution that is driven by independent multiple scatterings and branchings. These are controlled by the jet quenching parameter $\\hat q$. In this framework, large radiative corrections to $p_\\perp$-broadening of partons in the jet, enhanced by a double logarithm (DL) of the medium size $L$, are recovered. We argue that these non-local corrections are universal and can be reabsorbed in a renormalization of the jet quenching parameter without spoiling the probabilistic picture. As a consequence, we find that for large media, the mean radiative energy loss result scales as $L^{2+\\gamma}$, where the anomalous dimension $\\gamma=2\\sqrt{\\alpha_sN_c/\\pi}$.

Yacine Mehtar-Tani

2014-04-29T23:59:59.000Z

73

On fluid flow in a heterogeneous medium under nonisothermal conditions  

SciTech Connect (OSTI)

An asymptotic technique, valid in the presence of smoothly-varying heterogeneity, provides explicit expressions for the velocity of a propagating pressure and temperature disturbance. The governing equations contain nonlinear terms due to the presence of temperature-dependent coefficients and due to the advection of fluids with differing temperatures. Two cases give well-defined expressions in terms of the parameters of the porous medium: the uncoupled propagation of a pressure disturbance and the propagation of a fully coupled temperature and pressure disturbance. The velocity of the coupled disturbance or front, depends upon the medium parameters and upon the change in temperature and pressure across the front. For uncoupled flow, the semi-analytic expression for the front velocity reduces to that associated with a linear diffusion equation. A comparison of the asymptotic travel time estimates with calculations from a numerical simulator indicates reasonably good agreement for both uncoupled and coupled disturbances.

D.W., Vasco

2010-11-01T23:59:59.000Z

74

An Improved Treatment of Cosmological Intergalactic Medium Evolution  

E-Print Network [OSTI]

The modeling of galaxy formation and reionization, two central issues of modern cosmology, relies on the accurate follow-up of the intergalactic medium (IGM). Unfortunately, owing to the complex nature of this medium, the differential equations governing its ionization state and temperature are only approximate. In this paper, we improve these master equations. We derive new expression for the distinct composite inhomogeneous IGM phases, including all relevant ionizing/recombining and cooling/heating mechanisms, taking into account inflows/outflows into/from halos, and using more accurate recombination coefficients. Furthermore, to better compute the source functions in the equations we provide an analytic procedure for calculating the halo mass function in ionized environments, accounting for the bias due to the ionization state of their environment. Such an improved treatment of IGM evolution is part of a complete realistic model of galaxy formation presented elsewhere.

Manrique, Alberto

2015-01-01T23:59:59.000Z

75

Charmonium in a hot medium: melting vs absorption  

E-Print Network [OSTI]

A charmonium produced in heavy ion collisions at RHIC and LHC propagates through a dense co-moving matter with a rather high relative momentum, =4-10GeV^2. In spite of Debye screening of the binding potential, the charmonium survives with a substantial probability, even if the c-cbar potential is completely screened in the hot environment. In addition, the color-exchange interaction with the medium is another important source of charmonium suppression. Attenuation in a hot medium caused by both effects is evaluated by means of the path integral technique, which requires ability of boosting the binding potential to a moving reference frame. This problem is solved in the approximation of small intrinsic velocities of the charmed quarks.

B. Z. Kopeliovich; I. K. Potashnikova; Ivan Schmidt; M. Siddikov

2014-08-11T23:59:59.000Z

76

Medium and Heavy Duty Vehicle Field Evaluations (Presentation)  

SciTech Connect (OSTI)

This presentation discusses field evaluations of medium- and heavy-duty vehicles performed by NREL. The project provides medium-duty (MD) and heavy-duty (HD) test results, aggregated data, and detailed analysis, including 3rd party unbiased data (data that would not normally be shared by industry in an aggregated and detailed manner). Over 5.6 million miles of advanced technology MD and HD truck data have been collected, documented, and analyzed on over 240 different vehicles since 2002. Data, analysis, and reports are shared within DOE, national laboratory partners, and industry for R&D planning and strategy. The results help guide R&D for new technology development, help define intelligent usage of newly developed technology, and help fleets/users understand all aspects of advanced technology.

Walkowicz, K.

2014-06-01T23:59:59.000Z

77

Light scattering by radiation fields: the optical medium analogy  

E-Print Network [OSTI]

The optical medium analogy of a radiation field generated by either an exact gravitational plane wave or an exact electromagnetic wave in the framework of general relativity is developed. The equivalent medium of the associated background field is inhomogeneous and anisotropic in the former case, whereas it is inhomogeneous but isotropic in the latter. The features of light scattering are investigated by assuming the interaction region to be sandwiched between two flat spacetime regions, where light rays propagate along straight lines. Standard tools of ordinary wave optics are used to study the deflection of photon paths due to the interaction with the radiation fields, allowing for a comparison between the optical properties of the equivalent media associated with the different background fields.

Donato Bini; Pierluigi Fortini; Andrea Geralico; Maria Haney; Antonello Ortolan

2014-08-23T23:59:59.000Z

78

The Baryon Catastrophe and the multiphase intracluster medium  

E-Print Network [OSTI]

We review the theories and observations which together have led to the concept of the Baryon Catastrophe: observations of the baryon fraction on the scale of clusters of galaxies appear to be at least three times as high as the universal baryon fraction predicted by the theory of primordial nucleosynthesis in a flat, $\\Omega_0 = 1$, universe. We investigate whether this discrepancy could be eliminated by treating the intracluster gas as a multiphase medium, and find that this treatment both lowers the calculated mass of gas in a cluster and increases the inferred gravitational potential. These combined effects can reduce the calculated baryon fraction by between a quarter and a half: the precise amount depends upon the volume fraction distribution of density phases in the gas but is independent of the temperature profile across the cluster. Thus moving to a multiphase intracluster medium cannot resolve the Baryon Catastrophe by itself; other possible causes and explanations are discussed.

K. F. Gunn; P. A. Thomas

1995-10-17T23:59:59.000Z

79

Continuum Electrodynamics of a Piecewise-Homogeneous Linear Medium  

E-Print Network [OSTI]

The energy--momentum tensor and the tensor continuity equation serve as the conservation laws of energy, linear momentum, and angular momentum for a continuous flow. Previously, we derived equations of motion for macroscopic electromagnetic fields in a homogeneous linear dielectric medium that is draped with a gradient-index antireflection coating (J. Math Phys. 55, 042901 (2014) ). These results are consistent with the electromagnetic tensor continuity equation in the limit that reflections and the accompanying surface forces are negligible thereby satisfying the condition of an unimpeded flow in a thermodynamically closed system. Here, we take the next step and derive equations of motion for the macroscopic fields in the limiting case of a piecewise-homogeneous simple linear dielectric medium. The presence of radiation surface forces on the interface between two different homogeneous linear materials means that the energy--momentum formalism must be modified to treat separate homogeneous media in which the ...

Crenshaw, Michael E

2015-01-01T23:59:59.000Z

80

Translating Indian miniature paintings into a time-based medium  

E-Print Network [OSTI]

in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved by: Chair of Committee, Carol LaFayette Committee Members, Weiling He Michael Greenwald Head of Department, Tim McLaughlin May 2008 Major Subject...: Visualization Sciences iii ABSTRACT Translating Indian Miniature Paintings into a Time-based Medium. (May 2008) Aradhana Vaidya, B.Arch., Nagpur University, India Chair of Advisory Committee: Prof. Carol LaFayette The purpose of this research...

Vaidya, Aradhana

2008-10-10T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

RF-MEMS Switched Varactors for Medium Power Applications  

E-Print Network [OSTI]

In RF (Radio Frequency) domain, one of the limitations of using MEMS (Micro Electromechanical Systems) switching devices for medium power applications is RF power. Failure phenomena appear even for 500 mW. A design of MEMS switched capacitors with an enhanced topology is presented in this paper to prevent it. This kind of device and its promising performances will serve to fabricate a MEMS based phase shifter able to work under several watts.

Maury, F; Crunteanu, A; Conseil, F; Blondy, P

2008-01-01T23:59:59.000Z

82

Diffusion of hidden charm mesons in hadronic medium  

E-Print Network [OSTI]

The drag and diffusion coefficients of a hot hadronic medium have been evaluated by using hidden charm mesons as probes. The matrix elements for the evaluation of these coefficients are calculated using an effective theory as well as from scattering lengths. Although the transport coefficients show a significant rise with temperature its effects on the suppression of $J/\\psi$ in hadronic matter is not significant.

Sukanya Mitra; Sabyasachi Ghosh; Santosh K. Das; Sourav Sarkar; Jan-e Alam

2014-09-16T23:59:59.000Z

83

A CODEC for low to medium bit-rate video  

E-Print Network [OSTI]

(Members J. W. Howze (Head of Department) May 1990 A CODEC for Low to Medium Bit-rate Video. (May 1990) Victor Byron Taylor, B. S. , Texas A&M University; Chair of Advisory Committee: Dr. Jerry Gibson The compensated lattice quantizer (COMLAQ), is a... source coder/decoder (CODEC) designed for limited-motion videoconferencing applications. Our CODEC is based on four data compression strategies: lattice vector quantization, DPCM, transform coding, and simple interl'rame motion compensation. Designed...

Taylor, Victor Byron

1990-01-01T23:59:59.000Z

84

Optical Anisotropy of Schwarzschild Metric within Equivalent Medium Framework  

E-Print Network [OSTI]

It is has been long known that the curved space in the presence of gravitation can be described as a non-homogeneous anisotropic medium in flat geometry with different constitutive equations. In this article, we show that the eigenpolarizations of such medium can be exactly solved, leading to a pseudo-isotropic description of curved vacuum with two refractive index eigenvalues having opposite signs, which correspond to forward and backward travel in time. We conclude that for a rotating universe, time-reversal symmetry is broken. We also demonstrate the applicability of this method to Schwarzschild metric and derive exact forms of refractive index. We derive the subtle optical anisotropy of space around a spherically symmetric, non-rotating and uncharged blackhole in the form of an elegant closed form expression, and show that the refractive index in such a pseudo-isotropic system would be a function of coordinates as well as the direction of propagation. Corrections arising from such anisotropy in the bending of light are shown and a simplified system of equations for ray-tracing in the equivalent medium of Schwarzschild metric is found.

Sina Khorasani; Bizhan Rashidian

2009-12-16T23:59:59.000Z

85

E-Print Network 3.0 - anisotropic random medium Sample Search...  

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

39 Discrete-ordinates solution of short-pulsed laser transport in two-dimensional turbid media Summary: of the medium is L W 10 mm. The medium is anisotropically scattering with...

86

System-Response Issues Imposed by Biodiesel in a Medium-Duty...  

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

System-Response Issues Imposed by Biodiesel in a Medium-Duty Diesel Engine System-Response Issues Imposed by Biodiesel in a Medium-Duty Diesel Engine The objective of the current...

87

Jet Fragmentation in Medium and Vacuum with the PHENIX Detector  

E-Print Network [OSTI]

One of the most active areas of investigation in relativistic heavy-ion collisions is the study of the jet quenching phenomenon whereby hard partons lose their energy as they traverse the hot, dense matter created in such collisions. Strong parton energy loss has been observed in central nucleus-nucleus collisions as evidenced by the a large suppression of the yield of high pT hadrons as compared to the expected yield based on measurements in p+p collisions. Moreover, measurements of back-to-back correlations of charged hadrons suggest that jet shapes are strongly modified modified by the medium. The quantitative interpretation of single and di-hadron measurements is, however, complicated by the fact that the initial parton energy is unknown. A more informative measurement would be one in which the initial parton energy is known, allowing the determination of the fragmentation function, which may be effectively modified from its vacuum form by the presence of the medium. Two measurements in which the initial parton energy may be estimated are discussed in these proceedings: jet reconstruction and two- particle correlations using direct photons. Jet reconstruction in nuclear collisions is challenging due to the large background of soft particles, fluctuations of which give rise to fake jets. Direct photons can be used to estimate the initial parton energy of the recoil jet without recourse to jet reconstruction algorithms. However, such studies suffer from a smaller rate and the direct photon signal must be disentangled from a large background of decay photons. We present jet reconstruction results which use an algorithm suitable for a high multiplicity environment. We also present results of two-particle correlations using direct photons. These results are discussed in the context of medium modification to the fragmentation function.

Matthew Nguyen for the PHENIX Collaboration

2010-08-08T23:59:59.000Z

88

Process for modifying the metal ion sorption capacity of a medium  

DOE Patents [OSTI]

A process for modifying a medium is disclosed that includes treating a medium having a metal ion sorption capacity with a solution that includes: A) an agent capable of forming a complex with metal ions; and B) ions selected from the group consisting of sodium ions, potassium ions, magnesium ions, and combinations thereof, to create a medium having an increased capacity to sorb metal ions relative to the untreated medium.

Lundquist, Susan H. (White Bear Township, MN)

2002-01-01T23:59:59.000Z

89

A New Cavity Design For Medium Beta Acceleration  

SciTech Connect (OSTI)

Heavy duty or cw, superconducting proton and heavy ion accelerators are being proposed and constructed worldwide. The total length of the machine is one of the main drivers in terms of cost. Thus hwr and spoke cavities at medium beta are usually optimized to achieve low surface field and high gradient. A novel accelerating structure at beta=0.5 evolved from spoke cavity is proposed, with lower surface fields but slightly higher heat load. It would be an interesting option for pulsed and cw accelerators with beam energy of more than 200mev/u.

He, Feisi [Peking University, Beijing (China); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Wang, Haipeng [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Rimmer, Robert A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2014-02-01T23:59:59.000Z

90

Nuclear medium effects in $?(\\bar?)$-nucleus deep inelastic scattering  

E-Print Network [OSTI]

We study the nuclear medium effects in the weak structure functions $F_2(x,Q^2)$ and $F_3(x,Q^2)$ in the deep inelastic neutrino/antineutrino reactions in nuclei. We use a theoretical model for the nuclear spectral functions which incorporates the conventional nuclear effects, such as Fermi motion, binding and nucleon correlations. We also consider the pion and rho meson cloud contributions calculated from a microscopic model for meson-nucleus self-energies. The calculations have been performed using relativistic nuclear spectral functions which include nucleon correlations. Our results are compared with the experimental data of NuTeV and CDHSW.

H. Haider; I. Ruiz Simo; M. Sajjad Athar; M. J. Vicente Vacas

2011-08-16T23:59:59.000Z

91

On viscosity, conduction and sound waves in the intracluster medium  

E-Print Network [OSTI]

Recent X-ray and optical observations of the Perseus cluster indicate that the viscous and conductive dissipation of sound waves is the mechanism responsible for heating the intracluster medium and thus balancing radiative cooling of cluster cores. We discuss this mechanism more generally and show how the specific heating and cooling rates vary with temperature and radius. It appears that the heating mechanism is most effective above 10^7K, which allows for radiative cooling to proceed within normal galaxy formation but will stifle the growth of very massive galaxies. The scaling of the wavelength of sound waves with cluster temperature and feedback in the system are investigated.

A. C. Fabian; C. S. Reynolds; G. B. Taylor; R. J. H. Dunn

2005-08-04T23:59:59.000Z

92

Reference Buildings by Building Type: Medium office | Department of Energy  

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

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: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion | Department ofT ib l L dDepartmentnews-flashes Office ofofDepartment ofofofMedium office

93

Microscopic optical potentials of the nucleon-nucleus elastic scattering at medium energies  

E-Print Network [OSTI]

Microscopic optical potentials of the nucleon-nucleus elastic scattering at medium energies R interpreted in terms of the phenomenological optical model potential [1]. At medium and high energies of the optical model approach at medium energies has also some theoretical founda- tions. At a sufficiently large

Paris-Sud XI, Université de

94

Interacting FisherWright Diffusions in a Catalytic Medium Andreas Greven  

E-Print Network [OSTI]

environment (catalytic medium). Here we introduce a model of interacting Fisher­Wright diffusions where environment, catalytic medium, longtime behaviour, rescaling. AMS Subject Classification: 60K35, 60J70Interacting Fisher­Wright Diffusions in a Catalytic Medium Andreas Greven Mathematisches Institut

Klenke, Achim

95

Energy flow along the medium-induced parton cascade  

E-Print Network [OSTI]

We discuss the dynamics of parton cascades that develop in dense QCD matter, and contrast their properties with those of similar cascades of gluon radiation in vacuum. We argue that such cascades belong to two distinct classes that are characterized respectively by an increasing or a constant (or decreasing) branching rate along the cascade. In the former class, of which the BDMPS, medium-induced, cascade constitutes a typical example, it takes a finite time to transport a finite amount of energy to very soft quanta, while this time is essentially infinite in the latter case, to which the DGLAP cascade belongs. The medium induced cascade is accompanied by a constant flow of energy towards arbitrary soft modes, leading eventually to the accumulation of the initial energy of the leading particle at zero energy. It also exhibits scaling properties akin to wave turbulence. These properties do not show up in the cascade that develops in vacuum. There, the energy accumulates in the spectrum at smaller and smaller e...

Blaizot, Jean-Paul

2015-01-01T23:59:59.000Z

96

Ionization front-driven turbulence in the clumpy interstellar medium  

E-Print Network [OSTI]

We present 3D radiation-gasdynamical simulations of an ionization front running into a dense clump. In our setup, a B0 star irradiates an overdensity which is at a distance of 10 pc and modelled as a supercritical 100 M_sol Bonnor-Ebert sphere. The radiation from the star heats up the gas and creates a shock front that expands into the interstellar medium. The shock compresses the clump material while the ionizing radiation heats it up. The outcome of this "cloud-crushing" process is a fully turbulent gas in the wake of the clump. In the end, the clump entirely dissolves. We propose that this mechanism is very efficient in creating short-living supersonic turbulence in the vicinity of massive stars.

Thomas Peters; Robi Banerjee; Ralf S. Klessen

2008-08-20T23:59:59.000Z

97

Electrodynamic Casimir effect in a medium-filled wedge. II  

SciTech Connect (OSTI)

We consider the Casimir energy in a geometry of an infinite magnetodielectric wedge closed by a circularly cylindrical, perfectly reflecting arc embedded in another magnetodielectric medium, under the condition that the speed of light be the same in both media. An expression for the Casimir energy corresponding to the arc is obtained and it is found that in the limit where the reflectivity of the wedge boundaries tends to unity the finite part of the Casimir energy of a perfectly conducting wedge-shaped sheet closed by a circular cylinder is regained. The energy of the latter geometry possesses divergences due to the presence of sharp corners. We argue how this is a pathology of the assumption of ideal conductor boundaries and that no analogous term enters in the present geometry.

Ellingsen, Simen Aadnoey; Brevik, Iver; Milton, Kimball A. [Department of Energy and Process Engineering, Norwegian University of Science and Technology, N-7491 Trondheim (Norway); Oklahoma Center for High Energy Physics and H. L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, Oklahoma 73019 (United States)

2009-08-15T23:59:59.000Z

98

COSMIC RAY HEATING OF THE WARM IONIZED MEDIUM  

SciTech Connect (OSTI)

Observations of line ratios in the Milky Way's warm ionized medium suggest that photoionization is not the only heating mechanism present. For the additional heating to explain the discrepancy, it would have to have a weaker dependence on the gas density than the cooling rate, {Lambda}n{sub e}{sup 2}. Reynolds et al. suggested turbulent dissipation or magnetic field reconnection as possible heating sources. We investigate here the viability of MHD-wave mediated cosmic ray heating as a supplemental heating source. This heating rate depends on the gas density only through its linear dependence on the Alfven speed, which goes as n{sub e}{sup -1/2}. We show that, scaled to appropriate values of cosmic ray energy density, cosmic ray heating can be significant. Furthermore, this heating is stable to perturbations. These results should also apply to warm ionized gas in other galaxies.

Wiener, Joshua; Peng Oh, S. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States)] [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Zweibel, Ellen G. [Departments of Astronomy and Physics, and Center for Magnetic Self-Organization, University of Wisconsin-Madison, Madison, WI 53706 (United States)] [Departments of Astronomy and Physics, and Center for Magnetic Self-Organization, University of Wisconsin-Madison, Madison, WI 53706 (United States)

2013-04-10T23:59:59.000Z

99

Kansas Consortium Plug-in Hybrid Medium Duty  

SciTech Connect (OSTI)

On September 30, 2008, the US Department of Energy (DoE), issued a cooperative agreement award, DE-FC26-08NT01914, to the Metropolitan Energy Center (MEC), for a project known as “Kansas Consortium Plug-in Hybrid Medium Duty Certification” project. The cooperative agreement was awarded pursuant to H15915 in reference to H. R. 2764 Congressionally Directed Projects. The original agreement provided funding for The Consortium to implement the established project objectives as follows: (1) to understand the current state of the development of a test protocol for PHEV configurations; (2) to work with industry stakeholders to recommend a medium duty vehicle test protocol; (3) to utilize the Phase 1 Eaton PHEV F550 Chassis or other appropriate PHEV configurations to conduct emissions testing; (4) and to make an industry PHEV certification test protocol recommendation for medium duty trucks. Subsequent amendments to the initial agreement were made, the most significant being a revised Scope of Project Objectives (SOPO) that did not address actual field data since it was not available as originally expected. This project was mated by DOE with a parallel project award given to the South Coast Air Quality Management District (SCAQMD) in California. The SCAQMD project involved designing, building and testing of five medium duty plug-in hybrid electric trucks. SCAQMD had contracted with the Electric Power Research Institute (EPRI) to manage the project. EPRI provided the required match to the federal grant funds to both the SCAQMD project and the Kansas Consortium project. The rational for linking the two projects was that the data derived from the SCAQMD project could be used to validate the protocols developed by the Kansas Consortium team. At the same time, the consortium team would be a useful resource to SCAQMD in designating their test procedures for emissions and operating parameters and determining vehicle mileage. The years between award of the cooperative agreements and their completion were problematic for the US and world economies. This resulted in the President and Congress implementing the American Recovery and Reinvestment Act of 2009, abbreviated ARRA (Pub.L. 111-5), commonly referred to as the Stimulus or The Recovery Act. The stimulus money available for transportation projects encouraged the SCAQMD to seek additional funds. In August of 2009, they eventually were awarded an additional $45.5 M, and the scope of their project was expanded to 378 vehicles. However, as a consequence of the stimulus money and the inundation of DOE with applications for new project under the ARRA, the expected time table for producing and testing vehicles was significantly delayed. As a result, these vehicles were not available for validating the protocols developed by the Kansas Consortium. Therefore, in April of 2011, the Scope of Project Objectives (SOPO) for the project was revised, and limited to producing the draft protocol for PHEV certification as its deliverable.

None, None

2012-03-31T23:59:59.000Z

100

Medium Duty ARRA Data Reporting and Analysis (Presentation)  

SciTech Connect (OSTI)

This project compiles medium-duty (MD) aggregated deployment data and provides the compiled detailed analyses to industry. The U.S. Department of Energy's (DOE's) American Recovery and Reinvestment Act (ARRA) deployment and demonstration projects are helping to commercialize technologies for all-electric vehicles, electrified accessories, and electric charging infrastructure. Over 3.2 million miles of in-service all-electric MD truck data from 560 different vehicles have been collected since 2011, and usage data from over 1,000 truck electrification sites have been collected since 2013. Through the DOE's Vehicle Technologies Office, NREL is working to analyze real-time data from these deployment and demonstration projects to quantify the benefits: results and summary statistics are made available through the NREL website as quarterly and annual reports; 23 aggregated reports have been published on the performance and operation of these vehicles; and detailed data are being extracted to help further understand battery use and performance.

Walkowicz, K.

2014-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Two-phase flow in a chemically active porous medium  

E-Print Network [OSTI]

We study the problem of the transformation of a given reactant species into an immiscible product species, as they flow through a chemically active porous medium. We derive the equation governing the evolution of the volume fraction of the species -- in a one-dimensional macroscopic description --, identify the relevant dimensionless numbers, and provide simple models for capillary pressure and relative permeabilities, which are quantities of crucial importance when tackling multiphase flows in porous media. We set the domain of validity of our models and discuss the importance of viscous coupling terms in the extended Darcy's law. We investigate numerically the steady regime and demonstrate that the spatial transformation rate of the species along the reactor is non-monotonous, as testified by the existence of an inflection point in the volume fraction profiles. We obtain the scaling of the location of this inflection point with the dimensionless lengths of the problem. Eventually, we provide key elements for optimization of the reactor.

Alexandre Darmon; Michael Benzaquen; Thomas Salez; Olivier Dauchot

2014-11-20T23:59:59.000Z

102

Gravity currents in a porous medium at an inclined plane  

E-Print Network [OSTI]

We consider the release from a point source of relatively heavy fluid into a porous saturated medium above an impermeable slope. We consider the case where the volume of the resulting gravity current increases with time like $t^\\alpha$ and show that for $\\alpha3$, this situation is reversed with spreading occurring predominantly downslope for short times. The governing equations admit similarity solutions whose scaling behaviour we determine, with the full similarity form being evaluated by numerical computations of the governing partial differential equation. We find that the results of these analyses are in good quantitative agreement with a series of laboratory experiments. Finally, we briefly discuss the implications of our work for the sequestration of carbon dioxide in aquifers with a sloping, impermeable cap.

Vella, D; Huppert, Herbert E.; Vella, Dominic

2006-01-01T23:59:59.000Z

103

Nuclear structure studies with medium energy probes. [Northwestern Univ  

SciTech Connect (OSTI)

Progress in the continuing program of experimental research in nuclear structure with medium-energy probes during the year 1979-1980 is reviewed, and the research activities planned for the year 1980-1981 are discussed. In the study of pion-induced reactions emphasis is placed on investigation of isovector characteristics of nuclear excitations and on double charge exchange reactions. Pion production studies form the major part of the program of experiments with proton beams of 400 to 800 MeV at LAMPF. Current emphasis is on the bearing of these investigations on di-baryon existence. The study of high-spin states and magnetic scattering constitute the main goals of the electron scattering program at Bates. Representative results are presented; completed work is reported in the usual publications. (RWR)

Seth, Kamal K.

1980-01-01T23:59:59.000Z

104

Soot blower using fuel gas as blowing medium  

DOE Patents [OSTI]

A soot blower assembly (10) for use in combination with a coal gasifier (14). The soot blower assembly is adapted for use in the hot combustible product gas generated in the gasifier as the blowing medium. The soot blower lance (20) and the drive means (30) by which it is moved into and out of the gasifier is housed in a gas tight enclosure (40) which completely surrounds the combination. The interior of the enclosure (40) is pressurized by an inert gas to a pressure level higher than that present in the gasifier so that any combustible product gas leaking from the soot blower lance (20) is forced into the gasifier rather than accumulating within the enclosure.

Tanca, Michael C. (Tariffville, CT)

1982-01-01T23:59:59.000Z

105

Physics of the intra-cluster medium at high redshift  

E-Print Network [OSTI]

While the concept of "clustering" primarily refers to galaxies, the fact is that galaxies can be neglected - at least in terms of mass - when considering the continuous competition between accretion and relaxation processes of dark matter and gas, which control the dynamical life of galaxy clusters. Gravity is certainly the driving force in cluster formation and evolution, but is not sufficient to explain in detail the properties of the ICM brought to light by the most recent X-ray data: non thermal phenomena revealed by radio observations, micro-physics and feedback from galaxies play also a key role. From numerical simulations constrained by observations of the intra-cluster medium at low z, we attempt to extrapolate properties back in the time when density contrasts in the universe were much less pronounced.

M. Pierre

1999-10-25T23:59:59.000Z

106

Medium induced jet absorption at relativistic heavy ion collisions  

E-Print Network [OSTI]

The dense medium created in Au + Au collisions at the Relativistic Heavy-Ion Collider (RHIC) significantly suppresses particle production from hard scattering processes and their characteristic back-to-back angular correlation. We present a simple model of jet absorption in dense matter which incorporates a realistic nuclear geometry. Our calculations are performed at the jet level and assume independent jet fragmentation in the vacuum. This model describes quantitatively the centrality dependence of the observed suppression of the high $p_T$ hadron yield and of the back-to-back angular correlations. The azimuthal anisotropy of high $p_T$ particle production can not be accounted for using a realistic nuclear geometry.

Axel Drees; Haidong Feng; Jiangyong Jia

2005-05-31T23:59:59.000Z

107

DETECTION OF DIFFUSE NEUTRAL INTRAGROUP MEDIUM IN HICKSON COMPACT GROUPS  

SciTech Connect (OSTI)

We present new Green Bank Telescope (GBT) 21 cm neutral hydrogen (H I) observations of a complete distance-limited sample of 22 Hickson Compact Groups (HCGs) with at least four true members. We detected an average H I mass of 8 x 10{sup 9} M{sub sun} (median = 6 x 10{sup 9} M{sub sun}), which is significantly larger than previous single-dish measurements. Consequently, the H I deficiencies for these HCGs have been reduced, although not completely eliminated. Spectral comparison of the GBT data with complementary Very Large Array data shows significant H I excess in the GBT spectra. The observed excess is primarily due to the high surface brightness (HSB) sensitivity of the GBT detecting diffuse, low column density H I in these groups. The excess gas forms a faint diffused neutral medium which is an intermediate stage in the evolution of HSB H I tidal debris in the intragroup medium (IGM) before it is fully ionized. The excess gas mass fraction, (M(H I){sub GBT} - M(H I){sub VLA})/M(H I){sub GBT}, for our complete sample varies from 5% to 81% with an average of 36% (median = 30%). The excess gas mass fraction is highest in slightly H I deficient groups where the tidal debris has had enough time to evolve. We also find the excess gas content increases with the evolutionary phase of the group described in Verdes-Montenegro et al. Theoretical calculations indicate that an H I cloud of radius >= 200 pc would survive in an IGM of 2 x 10{sup 6} K for more than the typical dynamical lifetime of a group. However, smaller clouds get evaporated and assimilated into the hot IGM in a much shorter timescale.

Borthakur, Sanchayeeta; Yun, Min Su [Astronomy Department, University of Massachusetts, Amherst, MA 01003 (United States); Verdes-Montenegro, Lourdes, E-mail: sanch@astro.umass.ed, E-mail: myun@astro.umass.ed, E-mail: lourdes@iaa.e [Instituto de Astrofisica de AndalucIa, CSIC, Apdo. Correos 3004, E-18080 Granada (Spain)

2010-02-10T23:59:59.000Z

108

Magnetic and electric contributions to the energy loss in a dynamical QCD medium  

E-Print Network [OSTI]

The computation of radiative energy loss in a finite size QCD medium with dynamical constituents is a key ingredient for obtaining reliable predictions for jet quenching in ultra-relativistic heavy ion collisions. It was previously shown that energy loss in dynamical QCD medium is significantly higher compared to static QCD medium. To understand this difference, we here analyze magnetic and electric contributions to energy loss in dynamical QCD medium. We find that the significantly higher energy loss in the dynamical case is entirely due to appearance of magnetic contribution in the dynamical medium. While for asymptotically high energies, the energy loss in static and dynamical medium approach the same value, we find that the physical origin of the energy loss in these two cases is different.

Magdalena Djordjevic

2011-05-21T23:59:59.000Z

109

Vehicle Technologies Office Merit Review 2014: Medium and Heavy-Duty Vehicle Field Evaluations  

Broader source: Energy.gov [DOE]

Presentation given by National Renewable Energy Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about medium...

110

Vehicle Technologies Office Merit Review 2014: Medium Duty ARRA Data Reporting and Analysis  

Broader source: Energy.gov [DOE]

Presentation given by National Renewable Energy Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about medium...

111

In-Use Performance Results of Medium Duty Electric Vehicles (Presentation)  

SciTech Connect (OSTI)

This presentation describes a DOE program to monitor and report on vehicle performance and energy utilization of medium-duty and heavy-duty electric vehicles.

Walkowicz, K.

2012-07-01T23:59:59.000Z

112

Clean Cities' Guide to Alternative Fuel and Advanced Medium- and Heavy-Duty Vehicles (Brochure)  

SciTech Connect (OSTI)

Guide describes the alternative fuel and advanced medium- and heavy-duty vehicles available on the market, including buses, vans, refuse haulers, and more.

Not Available

2010-09-01T23:59:59.000Z

113

E-Print Network 3.0 - anisotropic porous medium Sample Search...  

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

Mathematics Page: << < 1 2 3 4 5 > >> Page: << < 1 2 3 4 5 > >> 21 Generalized radiative transfer equation for porous medium upscaling: application to the radiative Fourier...

114

antigen predicts medium-term: Topics by E-print Network  

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

in both disembodied and embodied technological change, research & development, and the efficiency of resource utilization. We then develop a model to explain the medium term...

115

E-Print Network 3.0 - adaptive medium access Sample Search Results  

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

physical layer of the Rice... . The flexible interrupt- driven interface between the PHY and the medium ... Source: Rice University, Center for Multimedia Communications...

116

Electric Field Calculations on Dry-Type Medium Voltage Current Transformers.  

E-Print Network [OSTI]

??This research presents potential and electric field calculations on medium voltage (MV) epoxy insulated outdoor current transformers (CTs) using a numeri-cal calculation approach. Two designs… (more)

Lakshmichand Jain, Sandeep Kumar

2012-01-01T23:59:59.000Z

117

Plasma Wave Properties of the Schwarzschild Magnetosphere in a Veselago Medium  

E-Print Network [OSTI]

We re-formulate the 3+1 GRMHD equations for the Schwarzschild black hole in a Veselago medium. Linear perturbation in rotating (non-magnetized and magnetized) plasma is introduced and their Fourier analysis is considered. We discuss wave properties with the help of wave vector, refractive index and change in refractive index in the form of graphs. It is concluded that some waves move away from the event horizon in this unusual medium. We conclude that for the rotating non-magnetized plasma, our results confirm the presence of Veselago medium while the rotating magnetized plasma does not provide any evidence for this medium.

M. Sharif; Noureen Mukhtar

2010-06-18T23:59:59.000Z

118

E-Print Network 3.0 - aqueous medium including Sample Search...  

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

8 Abstract Biological treatment methods are effective at destroying polycyclic aromatic hydro- Summary: concentrations in the aqueous phase medium (3 l) were tripled in response...

119

E-Print Network 3.0 - areas medium sized Sample Search Results  

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

that the Kozeny... states that the permeability of a medium is a function of the void fraction and the ... Source: Groningen, Rijksuniversiteit - Centre for Ecological and...

120

Commercialization of Medium Voltage HTS Triax TM Cable Systems  

SciTech Connect (OSTI)

The original project scope that was established in 2007 aimed to install a 1,700 meter (1.1 mile) medium voltage HTS Triax{TM} cable system into the utility grid in New Orleans, LA. In 2010, however, the utility partner withdrew from the project, so the 1,700 meter cable installation was cancelled and the scope of work was reduced. The work then concentrated on the specific barriers to commercialization of HTS cable technology. The modified scope included long-length HTS cable design and testing, high voltage factory test development, optimized cooling system development, and HTS cable life-cycle analysis. In 2012, Southwire again analyzed the market for HTS cables and deemed the near term market acceptance to be low. The scope of work was further reduced to the completion of tasks already started and to testing of the existing HTS cable system in Columbus, OH. The work completed under the project included: • Long-length cable modeling and analysis • HTS wire evaluation and testing • Cable testing for AC losses • Optimized cooling system design • Life cycle testing of the HTS cable in Columbus, OH • Project management. The 200 meter long HTS Triax{TM} cable in Columbus, OH was incorporated into the project under the initial scope changes as a test bed for life cycle testing as well as the site for an optimized HTS cable cooling system. The Columbus cable utilizes the HTS TriaxTM design, so it provided an economical tool for these of the project tasks.

Knoll, David

2012-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Energetic Electron Transport In An Inhomogeneous Plasma Medium  

SciTech Connect (OSTI)

A review of the work carried out at IPR on energetic electron transport through an inhomogeneous plasma medium is presented in this article. A Generalized Electron Magnetohydrodynamic (G-EMHD) fluid model has been developed and employed for such studies. Novel observations such as (i) the trapping of electron current pulse structure in a high density plasma region, (ii) the formation of sharp magnetic field shock structures at the inhomogeneous plasma density layer (iii) and intense energy dissipation at the shock layer even in the collisionless limit are reported. The intense energy dissipation of the electron current pulse at the shock layer provides a mechanism whereby highly energetic electrons which are essentially collision-less can also successfully deposit their energy in a local region of the plasma. This is specially attractive as it opens up the possibility of heating a localized region of an overdense plasma (where lasers cannot penetrate) by highly energetic collision-less electrons. A direct application of this mechanism to Fast Ignition (FT) experiments is discussed.

Das, Amita [Institute for Plasma Research, Bhat Gandhinagar-382428 (India)

2010-11-23T23:59:59.000Z

122

Corrections to Eikonal Approximation for Nuclear Scattering at Medium Energies  

E-Print Network [OSTI]

The upcoming Facility for Rare Isotope Beams (FRIB) at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University has reemphasized the importance of accurate modeling of low energy nucleus-nucleus scattering. Such calculations have been simplified by using the eikonal approximation. As a high energy approximation, however, its accuracy suffers for the medium energy beams that are of current experimental interest. A prescription developed by Wallace \\cite{Wallace:1971zz,Wallace:1973iu} that obtains the scattering propagator as an expansion around the eikonal propagator (Glauber approach) has the potential to extend the range of validity of the approximation to lower energies. Here we examine the properties of this expansion, and calculate the first-, second-, and third-order corrections for the scattering of a spinless particle off of a ${}^{40}$Ca nucleus, and for nuclear breakup reactions involving ${}^{11}$Be. We find that, including these corrections extends the lower bound of the range of validity of the down to energies of 40 MeV. At that energy the corrections provide as much as a 15\\% correction to certain processes.

Micah Buuck; Gerald A. Miller

2014-06-12T23:59:59.000Z

123

Nuclear thermodynamics and the in-medium chiral condensate  

E-Print Network [OSTI]

The temperature dependence of the chiral condensate in isospin-symmetric nuclear matter at varying baryon density is investigated using thermal in-medium chiral effective field theory. This framework provides a realistic approach to the thermodynamics of the correlated nuclear many-body system and permits calculating systematically the pion-mass dependence of the free energy per particle. One- and two-pion exchange processes, $\\Delta(1232)$-isobar excitations, Pauli blocking corrections and three-body correlations are treated up to and including three loops in the expansion of the free energy density. It is found that nuclear matter remains in the Nambu-Goldstone phase with spontaneously broken chiral symmetry in the temperature range $T\\lesssim 100\\,$MeV and at baryon densities at least up to about twice the density of normal nuclear matter, $2\\rho_0 \\simeq 0.3\\, $fm$^{-3}$. Effects of the nuclear liquid-gas phase transition on the chiral condensate at low temperatures are also discussed.

Salvatore Fiorilla; Norbert Kaiser; Wolfram Weise

2012-04-19T23:59:59.000Z

124

Method for producing low and medium BTU gas from coal  

SciTech Connect (OSTI)

A process for producing low and medium BTU gas from carbonizable material is described which comprises: partly devolatizing the material and forming hot incandescent coke therefrom by passing a bed of the same part way through a hot furnace chamber on a first horizontally moving grate while supplying a sub-stoichiometric quantity of air to the same and driving the reactions: C + O/sub 2/ = CO/sub 2/; 2C + O/sub 2/ = 2CO discharging the hot incandescent coke from the end of the first grate run onto a second horizontally moving grate run below the first grate run in the same furnace chamber so as to form a bed thereon, the bed formed on the second grate run being considerably thicker than the bed formed on the first grate run, passing the hot incandescent coke bed on the second grate run further through the furnace chamber in a substantially horizontal direction while feeding air and stream thereto so as to fully burn the coke and in ratio of steam to air driving the following reactions: 2C + O/sub 2/ = 2CO; C + H/sub 2/O = H/sub 2/ + CO; C + 2H/sub 2/O = 2H/sub 2/ + CO/sub 2/; CO + H/sub 2/O = H/sub 2/ + CO/sub 2/ taking off the ash residue of the burned coke and taking off the gaseous products of the reactions.

Mansfield, V.; Francoeur, C.M.

1988-06-07T23:59:59.000Z

125

The Galactic center interstellar medium as seen by ISO  

E-Print Network [OSTI]

This paper deals with the heating and the ionization of the interstellar medium (ISM) in the 500 central pc of the Milky Way (hereafter Galactic center, GC). We review the results of the Infrared Space Observatory (ISO) observations of a sample of GC molecular clouds located far from thermal radiocontinuum or far-infrared sources. For the first time, we have been able to study in detail the dust continuum spectra from 40 to 190 microns founding a warm (30-40 K) dust component in addition to the well known 15-20 K component. Fine-structure lines observations have revealed the presence of diffuse ionized gas associated with the molecular clouds. The effective temperature of the ionizing radiation is higher than 33000 K. ISO has also allow us to measure the fraction of warm (~ 150 K) H2 in the GC clouds, which is on average of 30 %. The observations of the warm (a few 100 K) neutral gas are compatible with a Photon Dominated Region (PDR) scenario.

N. J. Rodriguez-Fernandez; J. Martin-Pintado

2004-02-09T23:59:59.000Z

126

The Galactic Center Interstellar Medium: from ISO to FIRST  

E-Print Network [OSTI]

The Infrared Space Observatory (ISO) has shown the complexity of the Galactic center (GC) Interstellar medium (ISM) detecting, not only large column densities of warm molecular gas (H2), but the emission of neutral atoms and ions of low ionization potential (CII, OI, SiII,...) that should arise in shocked or photon-dominated regions (PDRs). In addition, ISO has also detected emission from ions like SIII, NeII, ArII, or NII (in some clouds we have even detected NeIII and OIII) that should arise from HII regions that were previously unsuspected due to the non-detection of Hydrogen recombination lines. Here we review some ISO results on the large scale study of the GC ISM and in particular, on the heating mechanisms of the clouds. Although, shocks should play an important role on the physics and chemistry of the GC ISM, ISO shows that the effect of radiation on the heating of the gas cannot be ruled out with the simple argument that the dust temperature is lower than that of the gas.

N. J. Rodriguez-Fernandez; J. Martin-Pintado

2001-01-19T23:59:59.000Z

127

Thermal Desorption of Water-Ice in the Interstellar Medium  

E-Print Network [OSTI]

Water (H2O) ice is an important solid constituent of many astrophysical environments. To comprehend the role of such ices in the chemistry and evolution of dense molecular clouds and comets, it is necessary to understand the freeze-out, potential surface reactivity, and desorption mechanisms of such molecular systems. Consequently, there is a real need from within the astronomical modelling community for accurate empirical molecular data pertaining to these processes. Here we give the first results of a laboratory programme to provide such data. Measurements of the thermal desorption of H2O ice, under interstellar conditions, are presented. For ice deposited under conditions that realistically mimic those in a dense molecular cloud, the thermal desorption of thin films (~50 molecular layers) is found to occur with zero order kinetics characterised by a surface binding energy, E_{des}, of 5773 +/- 60 K, and a pre-exponential factor, A, of 10^(30 +/- 2) molecules cm^-2 s^-1. These results imply that, in the dense interstellar medium, thermal desorption of H2O ice will occur at significantly higher temperatures than has previously been assumed.

Helen J. Fraser; Mark P. Collings; Martin R. S. McCoustra; David A. Williams

2001-07-25T23:59:59.000Z

128

Equilibration processes in the Warm-Hot Intergalactic Medium  

E-Print Network [OSTI]

The Warm-Hot Intergalactic Medium (WHIM) is thought to contribute about 40-50 % to the baryonic budget at the present evolution stage of the universe. The observed large scale structure is likely to be due to gravitational growth of density fluctuations in the post-inflation era. The evolving cosmic web is governed by non-linear gravitational growth of the initially weak density fluctuations in the dark energy dominated cosmology. Non-linear structure formation, accretion and merging processes, star forming and AGN activity produce gas shocks in the WHIM. Shock waves are converting a fraction of the gravitation power to thermal and non-thermal emission of baryonic/leptonic matter. They provide the most likely way to power the luminous matter in the WHIM. The plasma shocks in the WHIM are expected to be collisionless. Collisionless shocks produce a highly non-equilibrium state with anisotropic temperatures and a large differences in ion and electron temperatures. We discuss the ion and electron heating by the collisionless shocks and then review the plasma processes responsible for the Coulomb equilibration and collisional ionisation equilibrium of oxygen ions in the WHIM. MHD-turbulence produced by the strong collisionless shocks could provide a sizeable non-thermal contribution to the observed Doppler parameter of the UV line spectra of the WHIM.

A. M. Bykov; F. B. S. Paerels; V. Petrosian

2008-01-07T23:59:59.000Z

129

On the Crystallinity of Silicate Dust in the Interstellar Medium  

E-Print Network [OSTI]

An accurate knowledge of the mineralogy (chemical composition and crystal structure) of the silicate dust in the interstellar medium (ISM) is crucial for understanding its origin in evolved stars, the physical and chemical processing in the ISM, and its subsequent incorporation into protostellar nebulae, protoplanetary disks and cometary nuclei where it is subjected to further processing. While an appreciable fraction of silicate dust in evolved stars, in protoplanetary disks around pre-main sequence stars, in debris disks around main sequence stars, and in cometary nuclei is found to be in crystalline form, very recent infrared spectroscopic studies of the dust along the sightline toward the Galactic center source Sgr A* placed an upper limit of ~1.1% on the silicate crystalline fraction, well below the previous estimates of ~5% or ~60% derived from the observed 10 micron absorption profile for the local ISM toward Cyg OB2 No.12. Since the sightline toward SgrA contains molecular cloud materials as revealed by the detection of the 3.1 and 6.0 micron water ice absorption features, we argue that by taking into account the presence of ice mantles on silicate cores, the upper limit on the degree of silicate crystallinity in the ISM is increased to ~3--5%.

M. P. Li; G. Zhao; Aigen Li

2008-08-29T23:59:59.000Z

130

The Impact of Galactic Feedback on the Circumgalactic Medium  

E-Print Network [OSTI]

Galactic feedback strongly affects the way galactic environments are enriched. We examine this connection by performing a suite of cosmological hydrodynamic simulations, exploring a range of parameters based on the galaxy formation model developed in Vogelsberger et al. 2013 (henceforth V13). We examine the effects of AGN feedback, wind mass loading, wind specific energy, and wind metal-loading on the properties of the circumgalactic medium (CGM) of galaxies with $M_\\text{halo} > 10^{11} M_\\odot$. Note that while the V13 model was tuned to match observations including the stellar mass function, no explicit tuning was done for the CGM. The wind energy per unit outflow mass has the most significant effect on the CGM enrichment. High energy winds launch metals far beyond the virial radius. AGN feedback also has a significant effect, but only at $z < 3$. We compare to high redshift HI and CIV observations. All our simulations produce the observed number of Damped Lyman-$\\alpha$ Absorbers. At lower column densi...

Suresh, Joshua; Vogelsberger, Mark; Genel, Shy; Torrey, Paul; Sijacki, Debora; Springel, Volker; Hernquist, Lars

2015-01-01T23:59:59.000Z

131

TIMESCALES ON WHICH STAR FORMATION AFFECTS THE NEUTRAL INTERSTELLAR MEDIUM  

SciTech Connect (OSTI)

Turbulent neutral hydrogen (H I) line widths are often thought to be driven primarily by star formation (SF), but the timescale for converting SF energy to H I kinetic energy is unclear. As a complication, studies on the connection between H I line widths and SF in external galaxies often use broadband tracers for the SF rate, which must implicitly assume that SF histories (SFHs) have been constant over the timescale of the tracer. In this paper, we compare measures of H I energy to time-resolved SFHs in a number of nearby dwarf galaxies. We find that H I energy surface density is strongly correlated only with SF that occurred 30-40 Myr ago. This timescale corresponds to the approximate lifetime of the lowest mass supernova progenitors ({approx}8 M{sub Sun }). This analysis suggests that the coupling between SF and the neutral interstellar medium is strongest on this timescale, due either to an intrinsic delay between the release of the peak energy from SF or to the coherent effects of many supernova explosions during this interval. At {Sigma}{sub SFR} > 10{sup -3} M{sub Sun} yr{sup -1} kpc{sup -2}, we find a mean coupling efficiency between SF energy and H I energy of {epsilon} = 0.11 {+-} 0.04 using the 30-40 Myr timescale. However, unphysical efficiencies are required in lower {Sigma}{sub SFR} systems, implying that SF is not the primary driver of H I kinematics at {Sigma}{sub SFR} < 10{sup -3} M{sub Sun} yr{sup -1} kpc{sup -2}.

Stilp, Adrienne M.; Dalcanton, Julianne J.; Weisz, Daniel R.; Williams, Benjamin F. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Warren, Steven R. [Department of Astronomy, University of Maryland, CSS Building, Room 1024, Stadium Drive, College Park, MD 20742-2421 (United States); Skillman, Evan [Minnesota Institute for Astrophysics, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States); Ott, Juergen [National Radio Astronomy Observatory, P.O. Box O, 1003 Lopezville Road, Socorro, NM 87801 (United States); Dolphin, Andrew E. [Raytheon Company, 1151 East Hermans Road, Tucson, AZ 85756 (United States)

2013-08-01T23:59:59.000Z

132

TEMPORAL SMEARING OF TRANSIENT RADIO SOURCES BY THE INTERGALACTIC MEDIUM  

SciTech Connect (OSTI)

The temporal smearing of impulsive radio events at cosmological redshifts probes the properties of the ionized intergalactic medium (IGM). We relate the degree of temporal smearing and the profile of a scattered source to the evolution of a turbulent structure in the IGM as a function of redshift. We estimate the degree of scattering expected by analyzing the contributions to the scattering measure of the various components of baryonic matter embedded in the IGM, including the diffuse IGM, intervening galaxies, and intracluster gas. These estimates predict that the amount of temporal smearing expected at 300 MHz is typically as low as ?1 ms and suggests that these bursts may be detectable with low-frequency widefield arrays. A generalization of the dispersion-measure-scattering-measure relation observed for Galactic scattering to the densities and turbulent conditions relevant to the IGM suggests that scattering measures on the order of 10{sup –6} kpc m{sup –20/3} would be expected at z ? 1. This scattering is sufficiently low enough that its effects would not, for most lines of sight, be manifested in existing observations of the scatter broadening in images of extragalactic compact sources. The redshift dependence on the temporal smearing discriminates between scattering that occurs in the host galaxy of the burst and the IGM, with ?{sub host}?(1 + z){sup –3} if the scattering probes length scales below the inner scale of the turbulence or ?{sub host}?(1 + z){sup –17/5} if the turbulence follows a Kolmogorov spectrum. This differs strongly from the expected IGM scaling ?{sub IGM} ? z {sup 2} for z ?< 1 and (1 + z){sup 0.2–0.5} for z ?> 1.

Macquart, Jean-Pierre; Koay, Jun Yi, E-mail: J.Macquart@curtin.edu.au [ICRAR/Curtin University, Curtin Institute of Radio Astronomy, Perth WA 6845 (Australia)

2013-10-20T23:59:59.000Z

133

A pulser for medium-frequency modulated direct-current reactive sputter deposition of insulators  

E-Print Network [OSTI]

for medium-frequency modulated direct-current dc reactive sputter deposition of electrical insulators at the target surface inherent to high- deposition-rate reactive sputtering of electrical insulators. TypicallyA pulser for medium-frequency modulated direct-current reactive sputter deposition of insulators G

Cao, Hui

134

RANDOM WALK IN RANDOM ENVIRONMENT IN A TWO-DIMENSIONAL STRATIFIED MEDIUM WITH ORIENTATIONS  

E-Print Network [OSTI]

RANDOM WALK IN RANDOM ENVIRONMENT IN A TWO-DIMENSIONAL STRATIFIED MEDIUM WITH ORIENTATIONS ALEXIS walk in random environment, random walk in random scenery, functional limit theorem, transience. This research was supported by the french ANR project MEMEMO2. 1 #12;RWRE IN A STRATIFIED ORIENTED MEDIUM 2 Our

Pène, Françoise

135

RANDOM WALK IN RANDOM ENVIRONMENT IN A TWO-DIMENSIONAL STRATIFIED MEDIUM WITH ORIENTATIONS  

E-Print Network [OSTI]

RANDOM WALK IN RANDOM ENVIRONMENT IN A TWO-DIMENSIONAL STRATIFIED MEDIUM WITH ORIENTATIONS ALEXIS oriented lattices, random walk in random environment, random walk in random scenery, functional limit-00634636,version2-24Nov2012 #12;RWRE IN A STRATIFIED ORIENTED MEDIUM 2 We denote by E and E

Paris-Sud XI, Université de

136

Virtual Reality and Desktop as a Combined Interaction-Visualisation Medium for  

E-Print Network [OSTI]

these mediums within the same environment. 2. The Simulated Environment for Vascular Reconstruction 2Virtual Reality and Desktop as a Combined Interaction-Visualisation Medium for a Problem-Solving Environment E.V. Zudilova, P.M.A. Sloot Section Computational Science Faculty of Science, University

Zudilova-Seinstra, Elena

137

Behaviour of oil ganglia displaced by a surfactant solution in a porous medium  

E-Print Network [OSTI]

L-97 Behaviour of oil ganglia displaced by a surfactant solution in a porous medium J. C. Moulu'importance relative des forces de viscosité et des forces capillaires. Abstract. 2014 The velocity of oil ganglia residual oil phase by water injection in a porous medium [1, 2]. These studies have demonstrated

Boyer, Edmond

138

Ray Theory for a Locally Layered Random Medium K. S lna G. Papanicolaou y  

E-Print Network [OSTI]

variations in the medium parameters. The pulse is generated by a point source and the medium is modeled the source and the point of observation. The ray is determined by high frequency asymptotics (geometrical is motivated by wave propagation in sedimentary rock. Here the sedimentary cycles produce structures

Papanicolaou, George C.

139

The inuence of the interplanetary medium on SuperDARN radar scattering occurrence  

E-Print Network [OSTI]

in the frequency range 8±20 MHz (Greenwald et al., 1995). The level of scatter measured by the radars is highlyThe in¯uence of the interplanetary medium on SuperDARN radar scattering occurrence P. Ballatore1- planetary medium on the radar scattering occurrence, related to the whole array of SuperDARN radars

Paris-Sud XI, Université de

140

Thermal recovery from a fractured medium in local thermal non-equilibrium Rachel Geleta,b,  

E-Print Network [OSTI]

effective stress is tensile near the injection well, illustrating the thermal contraction of the rock, whileThermal recovery from a fractured medium in local thermal non-equilibrium Rachel Geleta, Australia Abstract Thermal recovery from a hot dry rock reservoir viewed as a deformable fractured medium

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "medium medium medium" 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

Range imaging: a new method for high-resolution topographic measurements in small-and medium-  

E-Print Network [OSTI]

Range imaging: a new method for high-resolution topographic measurements in small- and medium is a useful complement or alternative to existing methods for high-resolution measurements in small- to medium has led to a dramatic increase in terrain information and opened up new opportunities for hydro- logic

Kirchner, James W.

142

Sound-insulation layer modelling in car computational vibroacoustics in the medium-frequency range  

E-Print Network [OSTI]

Sound-insulation layer modelling in car computational vibroacoustics in the medium-frequency range In a previous article, a simplified low- and medium-frequency model for un- certain automotive sound-insulation. In this paper, the insulation simplified model is implemented in an in- dustrial stochastic vibroacoustic model

Boyer, Edmond

143

Copper dissolution in bromide medium in the absence and presence of hexamethylenetetramine (HMTA)  

E-Print Network [OSTI]

Copper dissolution in bromide medium in the absence and presence of hexamethylenetetramine (HMTA) A of copper in bromide medium, in the absence and presence of hexamethylenetetramine (HMTA), has been studied, using electrochemical and spectroelectrochemical techniques. The copper dissolution in the absence

Brolo, Alexandre G.

144

Mathematical model and simulation of gas ow through a porous medium in high breaking capacity  

E-Print Network [OSTI]

Mathematical model and simulation of gas #29;ow through a porous medium in high breaking capacity, France. Abstract. A one-dimensional model is introduced to describe the gas #29;ow and the heat transfer model coupled with a porous medium model taking into account the mechanical interaction gas-silica sand

Sart, Remi

145

Analysis of moisture variability in the European Centre for Medium-Range Weather Forecasts 15-year  

E-Print Network [OSTI]

Analysis of moisture variability in the European Centre for Medium-Range Weather Forecasts 15-year Centre for Medium-Range Weather Forecasts 15-year reanalysis (ERA-15) moisture over the tropical oceans. Introduction [2] Because water vapor is the most significant green- house gas and it exhibits a strong

Allan, Richard P.

146

Patterned medium for heat assisted magnetic recording Krat endur1,a  

E-Print Network [OSTI]

medium are compared using finite element method solutions of Maxwell's and the heat transfer equations a magnetic recording medium based on the fundamental principles of optical energy transfer and heat transfer. In this study, the basic principles of Maxwell's and heat transfer equations are utilized to obtain a magnetic

Yanikoglu, Berrin

147

The features of a quantum description of radiation in an optically dense medium  

E-Print Network [OSTI]

This paper is devoted to the theory of quantum electromagnetic field in an optically dense medium. Self-consistent equations describing interaction between a quantum field and a quantum dielectric medium are obtained from the first principles, i.e., outside a phenomenological description. Using these equations, we found a transformation (of the Bogoliubov transformation type) that converts the operators of the "vacuum" field into operators of collective perturbations of the field and an ensemble of atoms, that is, photons in the medium. Transformation parameter is the refractive index of the wave mode considered. It is shown that besides the energy of the collective electromagnetic field, the energy of photons in the medium includes the energy of the internal degrees of freedom of the substance and the energy of near-field dipole interaction between atoms in the polarized medium. The concept of negative energy photons is introduced on the basis of self-consistent equations.

Tokman, M D; Vdovin, V V

2015-01-01T23:59:59.000Z

148

TYPE Ia SUPERNOVAE STRONGLY INTERACTING WITH THEIR CIRCUMSTELLAR MEDIUM  

SciTech Connect (OSTI)

Owing to their utility for measurements of cosmic acceleration, Type Ia supernovae (SNe Ia) are perhaps the best-studied class of SNe, yet the progenitor systems of these explosions largely remain a mystery. A rare subclass of SNe Ia shows evidence of strong interaction with their circumstellar medium (CSM), and in particular, a hydrogen-rich CSM; we refer to them as SNe Ia-CSM. In the first systematic search for such systems, we have identified 16 SNe Ia-CSM, and here we present new spectra of 13 of them. Six SNe Ia-CSM have been well studied previously, three were previously known but are analyzed in depth for the first time here, and seven are new discoveries from the Palomar Transient Factory. The spectra of all SNe Ia-CSM are dominated by H{alpha} emission (with widths of {approx}2000 km s{sup -1}) and exhibit large H{alpha}/H{beta} intensity ratios (perhaps due to collisional excitation of hydrogen via the SN ejecta overtaking slower-moving CSM shells); moreover, they have an almost complete lack of He I emission. They also show possible evidence of dust formation through a decrease in the red wing of H{alpha} 75-100 days past maximum brightness, and nearly all SNe Ia-CSM exhibit strong Na I D absorption from the host galaxy. The absolute magnitudes (uncorrected for host-galaxy extinction) of SNe Ia-CSM are found to be -21.3 mag {<=} M{sub R} {<=} -19 mag, and they also seem to show ultraviolet emission at early times and strong infrared emission at late times (but no detected radio or X-ray emission). Finally, the host galaxies of SNe Ia-CSM are all late-type spirals similar to the Milky Way, or dwarf irregulars like the Large Magellanic Cloud, which implies that these objects come from a relatively young stellar population. This work represents the most detailed analysis of the SN Ia-CSM class to date.

Silverman, Jeffrey M. [Department of Astronomy, University of Texas, Austin, TX 78712-0259 (United States); Nugent, Peter E. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Gal-Yam, Avishay; Arcavi, Iair; Ben-Ami, Sagi [Benoziyo Center for Astrophysics, Weizmann Institute of Science, Rehovot 76100 (Israel); Sullivan, Mark [School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ (United Kingdom); Howell, D. Andrew; Graham, Melissa L. [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Filippenko, Alexei V.; Bloom, Joshua S.; Cenko, S. Bradley; Clubb, Kelsey I. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Cao, Yi; Horesh, Assaf; Kulkarni, Shrinivas R. [Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Chornock, Ryan; Foley, Ryan J. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Coil, Alison L. [Department of Physics, University of California, San Diego, La Jolla, CA 92093 (United States); Griffith, Christopher V. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Kasliwal, Mansi M., E-mail: jsilverman@astro.as.utexas.edu [Observatories of the Carnegie Institution of Science, Pasadena, CA 91101 (United States); and others

2013-07-01T23:59:59.000Z

149

A Self-Consistent Approach for Calculating the Effective Hydraulic Conductivity of a Bimodal, Heterogeneous Medium  

SciTech Connect (OSTI)

In this paper, we consider an approach for estimating the effective hydraulic conductivity of a 3D medium with a binary distribution of local hydraulic conductivities. The medium heterogeneity is represented by a combination of matrix medium conductivity with spatially distributed sets of inclusions. Estimation of effective conductivity is based on a self-consistent approach introduced by Shvidler (1985). The tensor of effective hydraulic conductivity is calculated numerically by using a simple system of equations for the main diagonal elements. Verification of the method is done by comparison with theoretical results for special cases and numerical results of Desbarats (1987) and our own numerical modeling. The method was applied to estimating the effective hydraulic conductivity of a 2D and 3D fractured porous medium. The medium heterogeneity is represented by a combination of matrix conductivity and a spatially distributed set of highly conductive fractures. The tensor of effective hydraulic conductivity is calculated for parallel- and random-oriented sets of fractures. The obtained effective conductivity values coincide with Romm's (1966) and Snow's (1969) theories for infinite fracture length. These values are also physically acceptable for the sparsely-fractured-medium case with low fracture spatial density and finite fracture length. Verification of the effective hydraulic conductivity obtained for a fractured porous medium is done by comparison with our own numerical modeling for a 3D case and with Malkovsky and Pek's (1995) results for a 2D case.

Pozdniakov, Sergey; Tsang, Chin-Fu

2004-01-02T23:59:59.000Z

150

Effect of high frequency modes of medium on an open quantum system  

E-Print Network [OSTI]

We present a method to calculate the real time effective propagator of a generic open quantum system, immersed in a medium using a wave function based framework. The medium is characterised by a set of harmonic oscillators having a continuous span of frequencies. This technique has been applied to the Caldeira-Leggett model showing that high frequency modes of the medium do not contribute towards decay of the population of states of the open system. In fact, they cause a Rabi type oscillation. Moreover, our wave function based approach provides an excellent alternative to conventional formalisms involving the density matrix.

Nirupam Dutta; A. K. Chaudhuri; P. K. Panigrahi

2014-09-09T23:59:59.000Z

151

Hot Plasma Waves Surrounding the Schwarzschild Event Horizon in a Veselago Medium  

E-Print Network [OSTI]

This paper investigates wave properties of hot plasma in a Veselago medium. For the Schwarzschild black hole, the $3+1$ GRMHD equations are re-formulated which are linearly perturbed and then Fourier analyzed for rotating (non-magnetized and magnetized) plasmas. The graphs of wave vector, refractive index and change in refractive are used to discuss the wave properties. The results obtained confirm the presence of Veselago medium for both rotating (non-magnetized and magnetized) plasmas. This work generalized the isothermal plasma waves in the Veselago medium to hot plasma case.

M. Sharif; Noureen Mukhtar

2011-01-05T23:59:59.000Z

152

-MAC: An Energy-Efficient Medium Access Control for Wireless Sensor Networks  

E-Print Network [OSTI]

-MAC: An Energy-Efficient Medium Access Control for Wireless Sensor Networks Andre Barroso, Utz: ¡ a.barroso u.roedig c.sreenan¢ @cs.ucc.ie Abstract-- For the long-term deployment of wireless sensor

Roedig, Utz

153

Analysis of asset health : an approach to monitoring and diagnostics for medium voltage circuit breakers  

E-Print Network [OSTI]

The Medium Voltage Electric Industry is a very conservative and risk adverse sector that has undergone very little change in the past 30 years when compared to other technologically dependent activities; this reality is ...

Corona, Erick (Erick Gustavo)

2013-01-01T23:59:59.000Z

154

Georgia Power- Small and Medium Scale Advanced Solar Initiative (GPASI) (Georgia)  

Broader source: Energy.gov [DOE]

'''''Note: The application process for the small and medium scale solar programs began on March 1, 2013 and will continue through March 11, 2013. If completed applications exceed program capacity...

155

Energy Conservation Through Heating/Cooling Retrofits in Small and Medium-Sized Industrial Plants  

E-Print Network [OSTI]

This paper discusses energy conservation projects in the area of industrial environment heating and cooling that have been recommended by the Texas A&M University Industrial Assessment Center (IAC) to small and medium-sized industries in Texas...

Saman, N.; Eggebrecht, J.

156

"Shelter within my reach" : medium rise apartment housing for the middle income group in Karachi, Pakistan  

E-Print Network [OSTI]

This thesis identifies the project development processes of medium rise (five storied or less) apartment housing built by the private formal sector, catering to the middle income groups in Karachi, Pakistan. Middle income ...

Mahmood, Saman, 1972-

1999-01-01T23:59:59.000Z

157

The Application of Ultrasonic Energy into Liquid Mediums to Increase Effectiveness  

E-Print Network [OSTI]

The use of high frequency or ultrasonic vibrations transmitted into and through a suitable medium can increase solution effectiveness. This means that in a continuous cleaning process, ultrasonic activation of the cleaning solution can increase...

Goodman, M. A.

1979-01-01T23:59:59.000Z

158

Organizational Learning and Knowledge Development Peculiarities in Small and Medium Family Enterprises  

E-Print Network [OSTI]

1 Organizational Learning and Knowledge Development Peculiarities in Small and Medium Family obstacles to organizational learning. Indeed, conservatism and independence orientation strongly influence Enterprises Abstract The aim of this theoretical contribution is to analyze the processes of organizational

Paris-Sud XI, Université de

159

Effect of bed medium moisture on {alpha}-pinene removal by biofilters  

SciTech Connect (OSTI)

In this study, laboratory scale continuous flow bioifilters were used to determine the effect of bed medium moisture on biofilter performance when treating off-gases containing {alpha}-pinene. Biofilters were packed using a proprietary wood waste bed medium and were operated at a flow rate of 700 ml of air per min, yielding an empty bed residence time of 2 minutes. For the bed medium moisture levels tested, a biofilter bed held at 100% moisture on a dry weight basis demonstrated the best overall {alpha}-pinene removal results. Volumetric productivity and percent removal were higher, while the time to reach maximum removal efficiency was decreased compared to biofilters operated at 40, 60 and 80% bed medium moisture. Results indicate that control of moisture in a biofilter is important for maximum removal of {alpha}-pinene.

Lee, B.D.; Apel, W.A.; Cook, L.L. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States); Nichols, K.M. [Weyerhaeuser, Federal Way, WA (United States)

1996-12-31T23:59:59.000Z

160

Development of a Chemically Defined Medium to Assay the Metabolism of Lactic Acid Bacteria  

E-Print Network [OSTI]

twelve chemically-defined ingredients. In order to increase the bioavailability of hydrophobic chemical additives, such as the isoflavone genistein (4',5,7-trihydroxyisoflavone), tween 80 was incorporated into the final medium at high levels (10% v...

Kim, Inhye

2014-04-16T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

The design of a compact integral medium size PWR : the CIRIS  

E-Print Network [OSTI]

The International Reactor Innovative and Secure (IRIS) is an advanced medium size, modular integral light water reactor design, rated currently at 1000 MWt. IRIS design has been under development by over 20 organizations ...

Shirvan, Koroush

2010-01-01T23:59:59.000Z

162

Hard and soft probe - medium interactions in a 3D hydro+micro approach at RHIC  

E-Print Network [OSTI]

We utilize a 3D hybrid hydro+micro model for a comprehensive and consistent description of soft and hard particle production in ultra-relativistic heavy-ion collisions at RHIC. In the soft sector we focus on the dynamics of (multi-)strange baryons, where a clear strangeness dependence of their collision rates and freeze-out is observed. In the hard sector we study the radiative energy loss of hard partons in a soft medium in the multiple soft scattering approximation. While the nuclear suppression factor $R_{AA}$ does not reflect the high quality of the medium description (except in a reduced systematic uncertainty in extracting the quenching power of the medium), the hydrodynamical model also allows to study different centralities and in particular the angular variation of $R_{AA}$ with respect to the reaction plane, allowing for a controlled variation of the in-medium path-length.

Bass, S A; Ruppert, J; Nonaka, C

2007-01-01T23:59:59.000Z

163

Green's Function expansion of scalar and vector fields in the presence of a medium  

E-Print Network [OSTI]

Based on a canonical approach and functional-integration techniques, a series expansion of Green's function of a scalar field, in the presence of a medium, is obtained. A series expansion for Lifshitz-energy, in finite-temperature, in terms of the susceptibility of the medium is derived and the whole formalism is generalized to the case of electromagnetic field in the presence of some dielectrics. A covariant formulation of the problem is presented.

Fardin Kheirandish; Shahriar Salimi

2010-10-17T23:59:59.000Z

164

Technical Support Document: 50% Energy Savings Design Technology Packages for Medium Office Buildings  

SciTech Connect (OSTI)

This Technical Support Document (TSD) describes the process and methodology for development of the Advanced Energy Design Guide for Medium Offices (AEDG-MO or the Guide), a design guidance document which intends to provide recommendations for achieving 50% energy savings in medium office buildings that just meet the requirements of ANSI/ASHRAE/IESNA Standard 90.1-2004, Energy Standard for Buildings Except Low-Rise Residential Buildings.

Thornton, Brian A.; Wang, Weimin; Lane, Michael D.; Rosenberg, Michael I.; Liu, Bing

2009-09-01T23:59:59.000Z

165

Chemical measurements of phosphorus avialability in some medium to fine textured soils  

E-Print Network [OSTI]

L]BRARY A A M COLLEGE OF TEXAS CHEMICAL MEASKKMEETS OF PHOSPHORUS AVAIIAHILITY IH SOME MEDIUM TO FINE TEXTURED SOILS HUGO A. VELASCO N. A Thesis Submitted to the Graduate School of the Agricultural and Mechanical College of Texas... in Partial fulfillment of the requirements for the degree oi' MASTER OF SCIEECE MAJOR SUBJECT: AGRONOMY Nay, 1956 CHEMICAL MEASUREMENTS OF PHOSPHORUS AVAILABILITY IN SOME MEDIUM TO FINE TEXTURED SOILS A Thesis Hugo A. Velasco M. Approved as to style...

Velasco Molina, Hugo Alejo

1956-01-01T23:59:59.000Z

166

Investigation into direct conversion with medium energy He-ion beams  

E-Print Network [OSTI]

INVESTIGATION INTO DIRECT ENERGY CONVERSION WITH MEDIUM ENERGY HELIUM-ION BEAMS A Thesis by AVERY ALLAN GUILD-BINGHAM Submitted to the Office of Graduate Studies of Texas A&M University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE December 2004 Major Subject: Nuclear Engineering INVESTIGATION INTO DIRECT ENERGY CONVERSION WITH MEDIUM ENERGY HELIUM-ION BEAMS A Thesis...

Guild-Bingham, Avery A.

2005-02-17T23:59:59.000Z

167

Emissions comparison between petroleum diesel and biodiesel in a medium-duty diesel engine  

E-Print Network [OSTI]

EMISSIONS COMPARISON BETWEEN PETROLEUM DIESEL AND BIODIESEL IN A MEDIUM-DUTY DIESEL ENGINE A Thesis by BRANDON T. TOMPKINS Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 2008 Major Subject: Mechanical Engineering EMISSIONS COMPARISON BETWEEN PETROLEUM DIESEL AND BIODIESEL IN A MEDIUM-DUTY DIESEL ENGINE A Thesis by BRANDON T...

Tompkins, Brandon T.

2009-05-15T23:59:59.000Z

168

System and method for monitoring water content or other dielectric influences in a medium  

DOE Patents [OSTI]

A sensor system is provided that measures water content or other detectable properties in a medium along the entire length of the sensor at any point in time. The sensor system includes an electromagnetic signal generator and a transmission line disposed in a medium to be monitored. Alternatively, the transmission line can be configured for movement across a medium to be monitored, or the transmission line can be fixed relative to a moving medium being monitored. A signal is transmitted along the transmission line at predetermined frequencies, and the signal is returned back along the transmission line and/or into an optional receive line in proximity to the transmission line. The returned signal is processed to generate a one-dimensional data output profile that is a function of a detectable property of the medium. The data output profile can be mapped onto a physical system to generate a two-dimensional or three-dimensional profile if desired. The sensor system is useful in a variety of different applications such as agriculture, horticulture, biofiltration systems for industrial offgases, leak detection in landfills or drum storage facilities at buried waste sites, and in many other applications.

Cherry, Robert S. (Idaho Falls, ID); Anderson, Allen A. (Firth, ID)

2001-01-01T23:59:59.000Z

169

Method for electrically producing dispersions of a nonconductive fluid in a conductive medium  

DOE Patents [OSTI]

A method is described for use in electrically forming dispersions of a nonconducting fluid in a conductive medium that minimizes power consumption, gas generation, and sparking between the electrode of the nozzle and the conductive medium. The method utilizes a nozzle having a passageway, the wall of which serves as the nozzle electrode, for the transport of the nonconducting fluid into the conductive medium. A second passageway provides for the transport of a flowing low conductivity buffer fluid which results in a region of the low conductivity buffer fluid immediately adjacent the outlet from the first passageway to create the necessary protection from high current drain and sparking. An electrical potential difference applied between the nozzle electrode and an electrode in contact with the conductive medium causes formation of small droplets or bubbles of the nonconducting fluid within the conductive medium. A preferred embodiment has the first and second passageways arranged in a concentric configuration, with the outlet tip of the first passageway withdrawn into the second passageway. 4 figs.

DePaoli, D.W.; Tsouris, C.; Feng, J.Q.

1998-06-09T23:59:59.000Z

170

Method for electrically producing dispersions of a nonconductive fluid in a conductive medium  

DOE Patents [OSTI]

A method for use in electrically forming dispersions of a nonconducting fluid in a conductive medium that minimizes power consumption, gas generation, and sparking between the electrode of the nozzle and the conductive medium. The method utilizes a nozzle having a passageway, the wall of which serves as the nozzle electrode, for the transport of the nonconducting fluid into the conductive medium. A second passageway provides for the transport of a flowing low conductivity buffer fluid which results in a region of the low conductivity buffer fluid immediately adjacent the outlet from the first passageway to create the necessary protection from high current drain and sparking. An electrical potential difference applied between the nozzle electrode and an electrode in contact with the conductive medium causes formation of small droplets or bubbles of the nonconducting fluid within the conductive medium. A preferred embodiment has the first and second passageways arranged in a concentric configuration, with the outlet tip of the first passageway withdrawn into the second passageway.

DePaoli, David W. (Knoxville, TN); Tsouris, Constantinos (Oak Ridge, TN); Feng, James Q. (Fairport, NY)

1998-01-01T23:59:59.000Z

171

Process for producing biodiesel, lubricants, and fuel and lubricant additives in a critical fluid medium  

DOE Patents [OSTI]

A process for producing alkyl esters useful in biofuels and lubricants by transesterifying glyceride- or esterifying free fatty acid-containing substances in a single critical phase medium is disclosed. The critical phase medium provides increased reaction rates, decreases the loss of catalyst or catalyst activity and improves the overall yield of desired product. The process involves the steps of dissolving an input glyceride- or free fatty acid-containing substance with an alcohol or water into a critical fluid medium; reacting the glyceride- or free fatty acid-containing substance with the alcohol or water input over either a solid or liquid acidic or basic catalyst and sequentially separating the products from each other and from the critical fluid medium, which critical fluid medium can then be recycled back in the process. The process significantly reduces the cost of producing additives or alternatives to automotive fuels and lubricants utilizing inexpensive glyceride- or free fatty acid-containing substances, such as animal fats, vegetable oils, rendered fats, and restaurant grease.

Ginosar, Daniel M.; Fox, Robert V.

2005-05-03T23:59:59.000Z

172

Can the Abraham Light Momentum and Energy in a Medium Constitute a Lorentz Four-Vector?  

E-Print Network [OSTI]

By analyzing the Einstein-box thought experiment with the principle of relativity, it is shown that Abraham's light momentum and energy in a medium cannot constitute a Lorentz four-vector, and they consequentially break global momentum and energy conservation laws. In contrast, Minkowski's momentum and energy always constitute a Lorentz four-vector no matter whether in a medium or in vacuum, and the Minkowski's momentum is the unique correct light momentum. A momentum-associated photon mass in a medium is exposed, which explains why only the Abraham's momentum is derived in the traditional "center-of-mass-energy" approach. The EM boundary-condition matching approach, combined with Einstein light-quantum hypothesis, is proposed to analyze this thought experiment, and it is found for the first time that only from Maxwell equations without resort to the relativity, the correctness of light momentum definitions cannot be identified. Optical pulling effect is studied as well.

Changbiao Wang

2014-09-04T23:59:59.000Z

173

Time Evolution of Tunneling in Thermal Medium -- Environment-driven Excited Tunneling --  

E-Print Network [OSTI]

Time evolution of tunneling phenomena proceeding in thermal medium is studied using a standard model of environment interaction. A semiclassical probability formula for the particle motion in a metastable state of one dimensional system put in thermal medium is combined with the formula of quantum penetration factor through a potential barrier, to derive the tunneling rate in medium. Effect of environment, its influence on time evolution in particular, is clarified in a real-time formalism. A nonlinear resonance effect is shown to enhance the tunneling rate at finite times of order $2/\\eta $, with $\\eta $ the friction coefficient. In the linear approximation this effect has relevance to the parametric resonance. This effect enhances the possibility of early termination of the cosmological phase transition much prior to the typical Hubble time.

Sh. Matsumoto; M. Yoshimura

2003-07-18T23:59:59.000Z

174

Method and apparatus for communicating computer data from one point to another over a communications medium  

DOE Patents [OSTI]

The present invention is directed toward a communications channel comprising a link level protocol, a driver, a receiver, and a canceller/equalizer. The link level protocol provides logic for DC-free signal encoding and recovery as well as supporting many features including CRC error detection and message resend to accommodate infrequent bit errors across the medium. The canceller/equalizer provides equalization for destabilized data signals and also provides simultaneous bi-directional data transfer. The receiver provides bit deskewing by removing synchronization error, or skewing, between data signals. The driver provides impedance controlling by monitoring the characteristics of the communications medium, like voltage or temperature, and providing a matching output impedance in the signal driver so that fewer distortions occur while the data travels across the communications medium.

Arneson, Michael R. (Chippewa Falls, WI); Bowman, Terrance L. (Sumner, WA); Cornett, Frank N. (Chippewa Falls, WI); DeRyckere, John F. (Eau Claire, WI); Hillert, Brian T. (Chippewa Falls, WI); Jenkins, Philip N. (Eau Claire, WI); Ma, Nan (Chippewa Falls, WI); Placek, Joseph M. (Chippewa Falls, WI); Ruesch, Rodney (Eau Claire, WI); Thorson, Gregory M. (Altoona, WI)

2007-07-24T23:59:59.000Z

175

Collisional parton energy loss in a finite size QCD medium revisited: Off mass-shell effects  

E-Print Network [OSTI]

We study the collisional energy loss mechanism for particles produced off mass-shell in a finite size QCD medium. The off mass-shell effects introduced are to consider particles produced in wave packets instead of plane waves and the length scale associated to an in-medium particles' life-time. We show that these effects reduce the energy loss as compared to the case when the particles are described as freely propagating from the source. The reduction of the energy loss is stronger as this scale becomes of the order or smaller than the medium size. We discuss possible consequences of the result on the description of the energy loss process in the parton recombination scenario.

Alejandro Ayala; J. Magnin; Luis Manuel Montano; Eduardo Rojas

2008-03-25T23:59:59.000Z

176

Energy dependence of $\\bar{K}N$ interaction in nuclear medium  

E-Print Network [OSTI]

When the $\\bar{K}N$ system is submerged in nuclear medium the $\\bar{K}N$ scattering amplitude and the final state branching ratios exhibit a strong energy dependence when going to energies below the $\\bar{K}N$ threshold. A sharp increase of $\\bar{K}N$ attraction below the $\\bar{K}N$ threshold provides a link between shallow $\\bar{K}$-nuclear potentials based on the chiral $\\bar{K}N$ amplitude evaluated at threshold and the deep phenomenological optical potentials obtained in fits to kaonic atoms data. We show the energy dependence of the in-medium $K^{-}p$ amplitude and demonstrate the impact of energy dependent branching ratios on the $\\Lambda$-hypernuclear production rates. \\keywords{kaon-nucleon amplitude \\and nuclear medium \\and hypernuclei

A. Cieply

2011-12-05T23:59:59.000Z

177

Multiple hot images from an obscuration in an intense laser beam through cascaded Kerr medium disks  

SciTech Connect (OSTI)

We present a theoretical investigation on the formation of hot images in an intense laser beam through cascaded Kerr medium disks, to disclose the distribution and intensity of hot images in high-power disk amplifiers. It is shown that multiple hot images from an obscuration may be formed, instead of one hot image as reported previously in the literature. This gives a clear explanation for the curious damage pattern of hot images, namely, damage sites appearing on alternating optics in periodic trains. Further analysis demonstrates that the distribution and intensity of hot images depend closely on the number of Kerr medium disks, the distance from the obscuration to the front of the first disk downstream, the space between two neighboring disks, and the thickness and B integral of each disk. Moreover, we take two cascaded Kerr medium disks for example to detail multiple hot images from an obscuration and confirm the theoretical results by numerical simulations.

Wang Youwen; Wen Shuangchun; You Kaiming; Tang Zhixiang; Deng Jianqin; Zhang Lifu; Fan Dianyuan

2008-10-20T23:59:59.000Z

178

Lattice NRQCD study on in-medium bottomonium spectra using a novel Bayesian reconstruction approach  

E-Print Network [OSTI]

We present recent results on the in-medium modification of S- and P-wave bottomonium states around the deconfinement transition. Our study uses lattice QCD with $N_f=2+1$ light quark flavors to describe the non-perturbative thermal QCD medium between $140$MeV$Maximum Entropy Method. Based on a systematic comparison of interacting and free spectral functions we conclude that the ground states of both the S-wave $(\\Upsilon)$ and P-wave $(\\chi_{b1})$ channel survive up to $T=249$MeV. Stringent upper limits on the size of the in-medium modification of bottomonium masses and widths are provided.

Seyong Kim; Peter Petreczky; Alexander Rothkopf

2014-11-12T23:59:59.000Z

179

Propagation of sound waves through a spatially homogeneous but smoothly time-dependent medium  

SciTech Connect (OSTI)

The propagation of sound through a spatially homogeneous but non-stationary medium is investigated within the framework of fluid dynamics. For a non-vortical fluid, especially, a generalized wave equation is derived for the (scalar) potential of the fluid velocity distribution in dependence of the equilibrium mass density of the fluid and the sound wave velocity. A solution of this equation for a finite transition period ? is determined in terms of the hypergeometric function for a phenomenologically realistic, sigmoidal change of the mass density and sound wave velocity. Using this solution, it is shown that the energy flux of the sound wave is not conserved but increases always for the propagation through a non-stationary medium, independent of whether the equilibrium mass density is increased or decreased. It is found, moreover, that this amplification of the transmitted wave arises from an energy exchange with the medium and that its flux is equal to the (total) flux of the incident and the reflected wave. An interpretation of the reflected wave as a propagation of sound backward in time is given in close analogy to Feynman and Stueckelberg for the propagation of anti-particles. The reflection and transmission coefficients of sound propagating through a non-stationary medium is analyzed in more detail for hypersonic waves with transition periods ? between 15 and 200 ps as well as the transformation of infrasound waves in non-stationary oceans. -- Highlights: •Analytically exact study of sound propagation through a non-stationary medium. •Energy exchange between the non-stationary medium and the sound wave. •Transformation of hypersonic and ultrasound frequencies in non-stationary media. •Propagation of sound backward in time in close analogy to anti-particles. •Prediction of tsunamis both in spatially and temporally inhomogeneous oceans.

Hayrapetyan, A.G., E-mail: armen@physi.uni-heidelberg.de [Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg (Germany); Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Grigoryan, K.K.; Petrosyan, R.G. [Yerevan State University, 1 Alex Manoogian Str., 0025 Yerevan (Armenia)] [Yerevan State University, 1 Alex Manoogian Str., 0025 Yerevan (Armenia); Fritzsche, S. [Helmholtz-Institut Jena, Fröbelstieg 3, D-07743 Jena (Germany) [Helmholtz-Institut Jena, Fröbelstieg 3, D-07743 Jena (Germany); Theoretisch-Physikalisches Institut, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, D-07743 Jena (Germany)

2013-06-15T23:59:59.000Z

180

Defining medium-specific condensates in QCD sum rules for $D$ and $B$ mesons  

E-Print Network [OSTI]

QCD sum rules for $D$ and $B$ mesons in a strongly interacting environment require the decomposition of Gibbs averaged operators related to tensor structures. We present a procedure to decompose these operators into vacuum and medium-specific parts, thus defining plain medium-specific condensates with coefficients vanishing in vacuum. Our decomposition allows for an identification of potential elements of order parameters for chiral restoration, in particular for higher mass-dimension quark-condensates which would be masked otherwise if operators with uncontracted Lorentz indices would be linked to DIS amplitudes.

T. Buchheim; T. Hilger; B. Kampfer

2014-09-08T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Quantum field theory in the presence of a medium: Green's function expansions  

SciTech Connect (OSTI)

Starting from a Lagrangian and using functional-integration techniques, series expansions of Green's function of a real scalar field and electromagnetic field, in the presence of a medium, are obtained. The parameter of expansion in these series is the susceptibility function of the medium. Relativistic and nonrelativistic Langevin-type equations are derived. Series expansions for Lifshitz energy in finite temperature and for an arbitrary matter distribution are derived. Covariant formulations for both scalar and electromagnetic fields are introduced. Two illustrative examples are given.

Kheirandish, Fardin [Department of Physics, Islamic Azad University, Shahreza-Branch, Shahreza (Iran, Islamic Republic of); Salimi, Shahriar [Department of Physics, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)

2011-12-15T23:59:59.000Z

182

In-medium nucleon-nucleon cross-sections with non-spherical Pauli blocking  

E-Print Network [OSTI]

We present a formalism to solve the Bethe-Goldstone scattering equation without the use of partial wave expansion which is alternative to the one we developed in a previous work. The present approach is more suitable for the calculation of in-medium nucleon-nucleon cross sections, which are the focal point of this paper. The impact of removing the spherical approximation on the angle and energy dependence of, particularly, in-medium proton-proton and proton-neutron differential cross sections is discussed along with its potential implication.

L. White; F. Sammarruca

2014-06-14T23:59:59.000Z

183

Omega Transmission Lines with Applications to Effective Medium Models of Metamaterials  

E-Print Network [OSTI]

In this paper we introduce the concept of transmission lines with inherent bi-anisotropy and establish an analogy between these lines and volumetric bi-anisotropic materials. In particular, we find under what conditions a periodically loaded transmission line can be treated as an effective omega medium. Two example circuits are introduced and analyzed. The results have two-fold implications: opening a route to emulate electromagnetic properties of bi-anisotropic omega media using transmission-line meshes and understanding and improving effective medium models of composite materials with the use of effective circuit models of unit cells.

Vehmas, Joni; Tretyakov, Sergei

2014-01-01T23:59:59.000Z

184

Visco-elastic fluid simulations of coherent structures in strongly coupled dusty plasma medium  

SciTech Connect (OSTI)

A generalized hydrodynamic model depicting the behaviour of visco-elastic fluids has often been invoked to explore the behaviour of a strongly coupled dusty plasma medium below their crystallization limit. The model has been successful in describing the collective normal modes of the strongly coupled dusty plasma medium observed experimentally. The paper focuses on the study of nonlinear dynamical characteristic features of this model. Specifically, the evolution of coherent vorticity patches is being investigated here within the framework of this model. A comparison with Newtonian fluids and molecular dynamics simulations treating the dust species interacting through the Yukawa potential has also been presented.

Singh Dharodi, Vikram; Kumar Tiwari, Sanat; Das, Amita, E-mail: amita@ipr.res.in [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

2014-07-15T23:59:59.000Z

185

Recipient luminophoric mediums having narrow spectrum luminescent materials and related semiconductor light emitting devices and methods  

DOE Patents [OSTI]

Light emitting devices include a light emitting diode ("LED") and a recipient luminophoric medium that is configured to down-convert at least some of the light emitted by the LED. In some embodiments, the recipient luminophoric medium includes a first broad-spectrum luminescent material and a narrow-spectrum luminescent material. The broad-spectrum luminescent material may down-convert radiation emitted by the LED to radiation having a peak wavelength in the red color range. The narrow-spectrum luminescent material may also down-convert radiation emitted by the LED into the cyan, green or red color range.

LeToquin, Ronan P; Tong, Tao; Glass, Robert C

2014-12-30T23:59:59.000Z

186

Role of noise operators on two-photon correlations in an extended coherent Raman medium  

E-Print Network [OSTI]

Role of noise operators on two-photon correlations in an extended coherent Raman medium C. H. Raymond Ooi1,2,3,4,* and M. Suhail Zubairy3,5 1Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon, 305-701 Korea 2Max... & Aerospace Engineering, Princeton University, New Jersey 08544, USA 5Texas A&M University at Qatar, Education City, P.O. Box 23874, Doha, Qatar #1;Received 8 January 2007; published 29 May 2007#2; An extended medium driven in a double Raman configuration...

Ooi, C. H. Raymond; Zubairy, M. Suhail.

2007-01-01T23:59:59.000Z

187

Representing Energy Price Variability in Long-and Medium-term Hydropower Optimization  

E-Print Network [OSTI]

1 Representing Energy Price Variability in Long- and Medium- term Hydropower Optimization Marcelo A Resources Planning and Management, 2012, in press ABSTRACT Representing peak and off-peak energy prices and examines the reliability of an existing approximate method to incorporate hourly energy price information

Pasternack, Gregory B.

188

Xylose utilizing zymomonas mobilis with improved ethanol production in biomass hydrolysate medium  

DOE Patents [OSTI]

Xylose-utilizing, ethanol producing strains of Zymomonas mobilis with improved performance in medium comprising biomass hydrolysate were isolated using an adaptation process. Independently isolated strains were found to have independent mutations in the same coding region. Mutation in this coding may be engineered to confer the improved phenotype.

Caimi, Perry G; Hitz, William D; Stieglitz, Barry; Viitanen, Paul V

2013-07-02T23:59:59.000Z

189

Xylose utilizing Zymomonas mobilis with improved ethanol production in biomass hydrolysate medium  

DOE Patents [OSTI]

Xylose-utilizing, ethanol producing strains of Zymomonas mobilis with improved performance in medium comprising biomass hydrolysate were isolated using an adaptation process. Independently isolated strains were found to have independent mutations in the same coding region. Mutation in this coding may be engineered to confer the improved phenotype.

Caimi, Perry G; Hitz, William D; Viitanen, Paul V; Stieglitz, Barry

2013-10-29T23:59:59.000Z

190

Pre-critical Chiral Fluctuations in Nuclear Medium -- precursors of chiral restoration at $?_{B}\  

E-Print Network [OSTI]

It is shown that an enhancement in the spectral function near 2$m_{\\pi}$ threshold in the I=J=0 channel is a good signal of the partial restoration of chiral symmetry in nuclear medium. Several experiments are discussed to detect the enhancement, which uses hadron-nucleus and photo-nucleus reactions.

T. Hatsuda; T. Kunihiro

1999-02-26T23:59:59.000Z

191

Synchronisation and MSW sharpening of neutrinos propagating in a flavour blind medium  

E-Print Network [OSTI]

We consider neutrino oscillations in a medium in which scattering processes are blind to the neutrino flavour. We present an analytical derivation of the synchronised behaviour obtained in the limit where the average scattering rate is much larger than the oscillation frequency. We also examine MSW transitions in these circumstances, and show that a sharpening of the transition can result.

Nicole F. Bell; R. F. Sawyer; Raymond R. Volkas

2001-01-05T23:59:59.000Z

192

HEALTH, SAFETY AND ENVIRONMENT MANAGEMENT SYSTEM : A METHOD FOR RANKING IMPACTS IN SMALL AND MEDIUM  

E-Print Network [OSTI]

99-57 HEALTH, SAFETY AND ENVIRONMENT MANAGEMENT SYSTEM : A METHOD FOR RANKING IMPACTS IN SMALL AND MEDIUM ENTERPRISES A. Accorsi', J.P. Pineau, A. Prats l. INERIS, Vemeuil-en-Halatte, France Key words : safety management System, ranking, health, safety, environment ABSTRACT ELF ATOCHEM and INERIS have

Paris-Sud XI, Université de

193

Multi-Gaussian Modes of Diffusion in a Quenched Random Medium Tapio Simula1  

E-Print Network [OSTI]

Multi-Gaussian Modes of Diffusion in a Quenched Random Medium Tapio Simula1 and Mikko Stenlund2,3 1 University of Helsinki, Finland We have studied a model of a random walk in a quenched random environment environments (RWRE) [3, 9­11]. In these models the environment describes the local propagation laws, which

194

Medium-Speed Drivetrain Test Report: September 1, 2002 -- December 30, 2007  

SciTech Connect (OSTI)

This report describes the tests conducted by researchers at the National Wind Technology Center at NREL on a 1.5-MW integrated drivetrain consisting of a single-stage, epicyclic gearbox and close-coupled medium-speed permanent-magnet generator.

Walford, C.; Lybarger, K.; Lettenmaier, T.; Roberts, D.

2012-09-01T23:59:59.000Z

195

668 / JOURNAL OF ENVIRONMENTAL ENGINEERING / JULY 1999 BACTERIAL TRANSPORT IN GAS-SPARGED POROUS MEDIUM  

E-Print Network [OSTI]

sparging a saturated porous medium produces a mobile water interface that was hypothesized to facilitate-aquifer remediation using bioaugmentation, more efficient meth- ods are needed to widely disperse pollutant-degrading bacteria in porous media. Under water-saturated condi- tions, bacteria readily adhere to soil particles

196

Focusing of an elongated hole in porous medium S. B. Angenent  

E-Print Network [OSTI]

which is valid for all m. This approximation indicates that the numerically observed power law behavior other applications such as population biology [21], diffusion of strong thermal waves [9], and, most. By Darcy's law, the velocity in porous medium flow is proportional to the pressure gradient. Thus, in order

197

MIMO Ad Hoc Networks: Medium Access Control, Saturation Throughput and Optimal Hop Distance  

E-Print Network [OSTI]

1 MIMO Ad Hoc Networks: Medium Access Control, Saturation Throughput and Optimal Hop Distance Ming in mobile ad hoc networks. Specifically, we focus on ad hoc networks where the spa- tial diversity technique technique can enhance the performance of mobile ad hoc networks significantly. Key words: ad hoc networks

Reisslein, Martin

198

Zymomonas with improved ethanol production in medium containing concentrated sugars and acetate  

DOE Patents [OSTI]

Through screening of a Zymomonas mutant library the himA gene was found to be involved in the inhibitory effect of acetate on Zymomonas performance. Xylose-utilizing Zymomonas further engineered to reduce activity of the himA gene were found to have increased ethanol production in comparison to a parental strain, when cultured in medium comprising xylose and acetate.

Caimi, Perry G. (Kennett Square, PA); Chou, Yat-Chen (Lakewood, CO); Franden, Mary Ann (Centennial, CO); Knoke, Kyle (Newark, DE); Tao, Luan (Havertown, PA); Viitanen, Paul V. (West Chester, PA); Zhang, Min (Lakewood, CO); Zhang, Yuying (New Hope, PA)

2010-09-28T23:59:59.000Z

199

Abstract, International Applied Geochemistry Symposium, 2009 Peat groundwater as a medium for surficial geochemical exploration  

E-Print Network [OSTI]

Abstract, International Applied Geochemistry Symposium, 2009 1 Peat groundwater as a medium-mail: stew.hamilton@ontario.ca) ABSTRACT: Kimberlite-specific chemical responses are visible in shallow peat and migrated through the Tyrell Sea sediment into shallow peat groundwater. The presence of elevated values

200

DOES ACCESS TO ELECTRICITY ENABLE THE UPTAKE OF SMALL AND MEDIUM ENTERPRISES IN SOUTH AFRICA?  

E-Print Network [OSTI]

1 DOES ACCESS TO ELECTRICITY ENABLE THE UPTAKE OF SMALL AND MEDIUM ENTERPRISES IN SOUTH AFRICA? G to electricity. The socio-political benefits of the national electrification programme are documented correlation of SMMEs and electricity access in poor rural areas does sem apparent. 1. INTRODUCTION The South

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


201

Synthesis of energy technology medium-term projections Alternative fuels for transport and low carbon electricity  

E-Print Network [OSTI]

carbon electricity generation: A technical note Robert Gross Ausilio Bauen ICEPT October 2005 #12;Alternative fuels for transport and electricity generation: A technical note on costs and cost projections ................................................................................................................. 3 Current and projected medium-term costs of electricity generating technologies....... 4 Biofuels

202

From fast to slow light in a resonantly driven absorbing medium Bruno Macke and Bernard Segard  

E-Print Network [OSTI]

the transmission time of the pulse center-of-mass (group delay), evidencing the relative contributions, 4]. More generally, due to the causality principle (originating the Kramers- Kronig relations), fast of a well-marked dip in the medium transmission and the pulse distortion resulting from the first order

Boyer, Edmond

203

PRINCIPLES OF ROBUST MEDIUM ACCESS AND AN APPLICATION TO LEADER ELECTION  

E-Print Network [OSTI]

PRINCIPLES OF ROBUST MEDIUM ACCESS AND AN APPLICATION TO LEADER ELECTION BARUCH AWERBUCH1, ANDREA nodes within transmission (and interference) range of each other, and we model the external disruptions-jammed time periods under any adversarial strategy above. The derived principles are also useful to build

Schmid, Stefan

204

An exact solution for the Casimir force in a spherically symmetric medium  

E-Print Network [OSTI]

We calculated the force of the quantum vacuum, the Casimir force, in a spherically symmetric medium, Maxwell's fish eye, surrounded by a perfect mirror and derived an exact analytic solution. Our solution questions the idea that the Casimir force of a spherical mirror is repulsive - we found an attractive force that diverges at the mirror.

Ulf Leonhardt; William M. R. Simpson

2011-07-03T23:59:59.000Z

205

Supplementation of canine oocyte in vitro maturation medium with progesterone, somatotropin, and epidermal growth factor  

E-Print Network [OSTI]

The aim of this project was to assess meiotic resumption of canine oocytes in vitro in response to medium supplemented with either progesterone (P?), somatotropin (ST), and/or epidermal growth factor (EGF). A mono-phasic in vitro maturation (IVM...

Willingham-Rocky, Lauri Ann

2001-01-01T23:59:59.000Z

206

Numerical modeling of hydraulic fracture problem in permeable medium using cohesive zone model  

E-Print Network [OSTI]

Numerical modeling of hydraulic fracture problem in permeable medium using cohesive zone model-off dominated. We demonstrate the ability of our cohesive zone model in simulating the hydraulic fracture in all these propagation regimes. Keywords: Hydraulic fracture, Cohesive zone model, Finite element analysis, Hydro

Paris-Sud XI, Université de

207

MODEL OF AGGREGATION OF SOLID PARTICLES IN NON-WETTING LIQUID MEDIUM  

E-Print Network [OSTI]

MODEL OF AGGREGATION OF SOLID PARTICLES IN NON- WETTING LIQUID MEDIUM M. Cournil, F.Gruy, P 30320, 57283 Maizières lès Metz, France Problem of modelling solid particles aggregation in non physical situations were little studied and deserve further works. This is the case of aggregation in non

Paris-Sud XI, Université de

208

Calculation of higher moments of the neutron multiplication process in a time-varying medium  

E-Print Network [OSTI]

, which only calculates this new component added and com- pletely ignores the zero-power reactor noiseCalculation of higher moments of the neutron multiplication process in a time-varying medium Y Available online 20 April 2007 Abstract The zero-power reactor noise theory in a steady neutron multiplying

Pázsit, Imre

209

A one-dimensional model of vertical gas plume migration through a heterogeneous porous medium  

E-Print Network [OSTI]

A one-dimensional model of vertical gas plume migration through a heterogeneous porous medium and consequent global warming. Ideally, the injected greenhouse gas stays in the injection zone for a geologic or inadvertently created conduits in the cap rock may result in a gas leakage from primary storage. Even

Patzek, Tadeusz W.

210

Method for encapsulating and isolating hazardous cations, medium for encapsulating and isolating hazardous cations  

DOE Patents [OSTI]

A method for encapsulating hazardous cations is provided comprising supplying a pretreated substrate containing the cations; contacting the substrate with an organo-silane compound to form a coating on the substrate; and allowing the coating to cure. A medium for containing hazardous cations is also provided, comprising a substrate having ion-exchange capacity and a silane-containing coating on the substrate.

Wasserman, Stephen R. (Darien, IL); Anderson, Kenneth B. (Lisle, IL); Song, Kang (Woodridge, IL); Yuchs, Steven E. (Naperville, IL); Marshall, Christopher L. (Naperville, IL)

1998-01-01T23:59:59.000Z

211

In-medium effects for nuclear matter in the Fermi energy domain D. Durand,1  

E-Print Network [OSTI]

In-medium effects for nuclear matter in the Fermi energy domain O. Lopez,1 D. Durand,1 G. Lehaut,1 of nuclear reactions in the Fermi energy domain. I. INTRODUCTION Transport properties in nuclear matter energy domain, transport features should exhibit the in- terplay between mean-field (nuclear degrees

Boyer, Edmond

212

Average crack front velocity during subcritical fracture propagation in a heterogeneous medium  

E-Print Network [OSTI]

Average crack front velocity during subcritical fracture propagation in a heterogeneous medium relaxation tests, exploring subcritical to critical regimes. Transparency of the material (PMMA) allows kinetic crack propagation is usually referred to as sub-critical crack growth or sub- critical regime

Paris-Sud XI, Université de

213

A Game Theoretic Approach for Medium Access of Open Spectrum in Cognitive Radios  

E-Print Network [OSTI]

A Game Theoretic Approach for Medium Access of Open Spectrum in Cognitive Radios Madhusudhan R broadcast [2]. The U.S. DARPA Next Generation Com- open spectrum for spectrum agile radios that use spectrum radios. Spectrum funding Program (FP6) of the European Union are working agile radios operate in parts

Chronopoulos, Anthony T.

214

Analysis, simulation and impedance operator of a non local model of porous medium for  

E-Print Network [OSTI]

of a porous wall devoted to aircraft motor noise reduction. For such a medium, the parameters motor noise reduction is currently an important challenge for aerospace industry. Control of acoustic manuscript, published in "Journal of Vibration and Control (2013) -" DOI : 10.1177/1077546313493815 #12

Paris-Sud XI, Université de

215

VALIDATION OF SHORT AND MEDIUM TERM OPERATIONAL SOLAR RADIATION FORECASTS IN THE US  

E-Print Network [OSTI]

VALIDATION OF SHORT AND MEDIUM TERM OPERATIONAL SOLAR RADIATION FORECASTS IN THE US Richard Perez This paper presents an initial validation of a solar radiation service that provides historical, as well observed solar radiation conditions based on immediate measured history: The position and impact of future

Perez, Richard R.

216

Longitudinal singular response of dusty plasma medium in weak and strong coupling limits  

SciTech Connect (OSTI)

The longitudinal response of a dusty plasma medium in both weak and strong coupling limits has been investigated in detail using analytic as well as numerical techniques. In particular, studies on singular response of the medium have been specifically investigated here. A proper Galilean invariant form of the generalized hydrodynamic fluid model has been adopted for the description of the dusty plasma medium. For weak non-linear response, analytic reductive perturbative approach has been adopted. It is well known that in the weak coupling regime for the dusty plasma medium, such an analysis leads to the Korteweg-de Vries equation (KdV) equation and predicts the existence of localized smooth soliton solutions. We show that the strongly coupled dust fluid with the correct Galilean invariant form does not follow the KdV paradigm. Instead, it reduces to the form of Hunter-Saxton equation, which does not permit soliton solutions. The system in this case displays singular response with both conservative as well as dissipative attributes. At arbitrary high amplitudes, the existence and spontaneous formation of sharply peaked cusp structures in both weak and strong coupling regimes has been demonstrated numerically.

Kumar Tiwari, Sanat; Das, Amita; Kaw, Predhiman; Sen, Abhijit [Institute for Plasma Research, Bhat, Gandhinagar - 382428 (India)

2012-01-15T23:59:59.000Z

217

dance. But, if we assume that the true iron abundance of the hot interstellar medium is  

E-Print Network [OSTI]

that the hot compo- nent is not in hydrostatic equilibrium and is the basic driving force for the galactic wind outflow of chemically enriched material into the intergalactic medium. Such high- temperature plasmas, D. A. Schwartz, J. Schwarz, J. C. Blades, Astrophys. J. 230, L21 (1979). 9. M. G. Watson, V. Stanger

Tlusty, Tsvi

218

Combustion System Development for Medium-Sized Industrial Gas Turbines: Meeting Tight Emission Regulations while Using  

E-Print Network [OSTI]

Combustion System Development for Medium-Sized Industrial Gas Turbines: Meeting Tight Emission Regulations while Using a Broad Range of Alternative Fuels Luke Cowell. Solar Turbines Abstract: Solar Turbines Incorporated is a leading manufacturer of industrial gas turbine packages for the power generation

Ponce, V. Miguel

219

Energy-Efficient Medium Access Control Koen Langendoen and Gertjan Halkes  

E-Print Network [OSTI]

of Technology Faculty of Electrical Engineering, Mathematics and Computer Science Mekelweg 4, 2628CD Delft, it has a large impact on the overall energy consumption, and hence, the lifetime of a node. Physical will now provide a brief historic perspective on the evolution of medium access control, and describe

Chen, Yuanzhu Peter

220

Confirmation of X-ray Absorption by Warm-hot Intergalactic Medium in the Sculptor Wall  

E-Print Network [OSTI]

In a previous paper, we reported a 3? detection of an absorption line from the warm-hot intergalactic medium (WHIM) using the Chandra and XMM X-ray grating spectra of the blazar H2356-309, the sight line of which intercepts ...

Fang, Taotao

Note: This page contains sample records for the topic "medium medium medium" 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

Crystallization and spectroscopic characterizations of medium-pore zeolites in the aluminoferrisilicate system  

SciTech Connect (OSTI)

Results establish the important result that medium-pore aluminoferrisilicate zeolites can be synthesized, which have the ZSM-5-type structure, and have Fe/sup 3 +/ ions in both framework and non-framework sites. The non-framework cations would therefore serve as charge-balancing cations.

Iton, L.E.; Beal, R.B.

1983-01-01T23:59:59.000Z

222

Polymeric medium  

DOE Patents [OSTI]

A PBI compound includes imidazole nitrogens at least a portion of which are substituted with a moiety containing a carbonyl group, the substituted imidazole nitrogens being bonded to carbon of the carbonyl group. At least 85% of the nitrogens may be substituted. The carbonyl-containing moiety may include RCO--, where R is alkoxy or haloalkyl. The PBI compound may exhibit a first temperature marking an onset of weight loss corresponding to reversion of the substituted PBI that is less than a second temperature marking an onset of decomposition of an otherwise identical PBI compound without the substituted moiety. The PBI compound may be included in separatory media. A substituted PBI synthesis method may include providing a parent PBI in a less than 5 wt % solvent solution. Substituting may use more than 5 equivalents in relation to the imidazole nitrogens to be substituted.

Klaehn, John R. (Idaho Falls, ID); Peterson, Eric S. (Idaho Falls, ID); Orme, Christopher J. (Shelley, ID); Jones, Michael G. (Chubbuck, ID); Wertsching, Alan K. (Idaho Falls, ID); Luther, Thomas A. (Idaho Falls, ID); Trowbridge, Tammy L. (Idaho Falls, ID)

2012-03-06T23:59:59.000Z

223

Cell damage extent due to irradiation with nanosecond laser pulses under cell culturing medium and dry environment  

E-Print Network [OSTI]

Cell damage extent due to irradiation with nanosecond laser pulses under cell culturing medium and dry environment Francisco G. Pérez-Gutiérrez1 , Gabriel Guillen2 , Rodger Evans3 Santiago Camacho with nanosecond laser pulses under two distinct scenarios: (a) with culturing medium positioning the beam waist

Aguilar, Guillermo

224

The Fracture Toughness of Medium Density Fiberboard (MDF) Including the Effects of Fiber Bridging and Crack-Plane Interference  

E-Print Network [OSTI]

1 The Fracture Toughness of Medium Density Fiberboard (MDF) Including the Effects of Fiber Bridging University, Corvallis, OR, USA Abstract The fracture toughness of medium density fiberboard (MDF) as a function of crack length (R curve) was measured. Fracture toughness was determined from force

Nairn, John A.

225

QUANTIFYING THE COMBINED EFFECTS OF THE HEATING TIME,1 THE TEMPERATURE AND THE RECOVERY MEDIUM PH ON THE2  

E-Print Network [OSTI]

QUANTIFYING THE COMBINED EFFECTS OF THE HEATING TIME,1 THE TEMPERATURE AND THE RECOVERY MEDIUM PH of the conditions of the heat treatment: temperature, duration15 and pH of the recovery medium. For a given heating Keywords: Bacillus cereus, heat treatment, lag time, recovery.29 30 1. Introduction31 32 Bacillus cereus

Paris-Sud XI, Université de

226

Fluid breakup during simultaneous two-phase flow through a three-dimensional porous medium  

E-Print Network [OSTI]

We use confocal microscopy to directly visualize the simultaneous flow of both a wetting and a non-wetting fluid through a model three-dimensional (3D) porous medium. We find that, for small flow rates, both fluids flow through unchanging, distinct, connected 3D pathways; in stark contrast, at sufficiently large flow rates, the non-wetting fluid is broken up into discrete ganglia. By performing experiments over a range of flow rates, using fluids of different viscosities, and with porous media having different geometries, we show that this transition can be characterized by a state diagram that depends on the capillary numbers of both fluids, suggesting that it is controlled by the competition between the viscous forces exerted on the flowing oil and the capillary forces at the pore scale. Our results thus help elucidate the diverse range of behaviors that arise in two-phase flow through a 3D porous medium.

Sujit S. Datta; Jean-Baptiste Dupin; David A. Weitz

2014-06-26T23:59:59.000Z

227

Analysis of energy-efficiency investment decisions by small and medium-sized manufacturers  

SciTech Connect (OSTI)

This report highlights the results of a comprehensive analysis of investment decisions regarding energy-efficiency measures at small and medium-sized manufacturing plants. The analysis is based on the experiences of companies participating in the DOE Industrial Assessment Center (IAC) program. The IAC program is a network of university-based centers that provides energy and waste assessments to small and medium-sized manufacturing plants. The purposes of this report are to do the following: (1) Examine what the data collected reveal about patterns of implementation of recommended energy- efficiency measures, (2) Evaluate how various factors, such as the type of industry, the characteristics of the manufacturing plants, or the cost of the measures, appear to effect implementation rates, (3) Examine reasons why recommended energy-saving measures are accepted or rejected.

Woodruff, M.G.; Roop, J.M.; Seely, H.E. [Pacific Northwest National Lab., Richland, WA (United States); Muller, M.R. [Rutgers--the State Univ., New Brunswick, NJ (United States); Jones, T.W. [Alliance to Save Energy, Washington, DC (United States); Dowd, J. [USDOE, Washington, DC (United States)

1996-05-01T23:59:59.000Z

228

Comparative analysis of the secondary electron yield from carbon nanoparticles and pure water medium  

E-Print Network [OSTI]

The production of secondary electrons generated by carbon nanoparticles and pure water medium irradiated by fast protons is studied by means of model approaches and Monte Carlo simulations. It is demonstrated that due to a prominent collective response to an external field, the nanoparticles embedded in the medium enhance the yield of low-energy electrons. The maximal enhancement is observed for electrons in the energy range where plasmons, which are excited in the nanoparticles, play the dominant role. Electron yield from a solid carbon nanoparticle composed of fullerite, a crystalline form of C60 fullerene, is demonstrated to be several times higher than that from liquid water. Decay of plasmon excitations in carbon-based nanosystems thus represents a mechanism of increase of the low-energy electron yield, similar to the case of sensitizing metal nanoparticles. This observation gives a hint for investigation of novel types of sensitizers to be composed of metallic and organic parts.

Verkhovtsev, Alexey; de Vera, Pablo; Surdutovich, Eugene; Guatelli, Susanna; Korol, Andrei V; Rosenfeld, Anatoly; Solov'yov, Andrey V

2015-01-01T23:59:59.000Z

229

Calculating alpha Eigenvalues in a Continuous-Energy Infinite Medium with Monte Carlo  

SciTech Connect (OSTI)

The {alpha} eigenvalue has implications for time-dependent problems where the system is sub- or supercritical. We present methods and results from calculating the {alpha}-eigenvalue spectrum for a continuous-energy infinite medium with a simplified Monte Carlo transport code. We formulate the {alpha}-eigenvalue problem, detail the Monte Carlo code physics, and provide verification and results. We have a method for calculating the {alpha}-eigenvalue spectrum in a continuous-energy infinite-medium. The continuous-time Markov process described by the transition rate matrix provides a way of obtaining the {alpha}-eigenvalue spectrum and kinetic modes. These are useful for the approximation of the time dependence of the system.

Betzler, Benjamin R. [Los Alamos National Laboratory; Kiedrowski, Brian C. [Los Alamos National Laboratory; Brown, Forrest B. [Los Alamos National Laboratory; Martin, William R. [Los Alamos National Laboratory

2012-09-04T23:59:59.000Z

230

Development and Demonstration of a Low Cost Hybrid Drive Train for Medium and Heavy Duty Vehicles  

SciTech Connect (OSTI)

The DOE sponsored effort is part of a larger effort to quantify the efficiency of hybrid powertrain systems through testing and modeling. The focus of the DOE sponsored activity was the design, development and testing of hardware to evaluate the efficiency of the electrical motors relevant to medium duty vehicles. Medium duty hybrid powertrain motors and generators were designed, fabricated, setup and tested. The motors were a permanent magnet configuration, constructed at Electric Apparatus Corporation in Howell, Michigan. The purpose of this was to identify the potential gains in terms of fuel cost savings that could be realized by implementation of such a configuration. As the electric motors constructed were prototype designs, the scope of the project did not include calculation of the costs of mass production of the subject electrical motors or generator.

Strangas, Elias; Schock, Harold; Zhu, Guoming; Moran, Kevin; Ruckle, Trevor; Foster, Shanelle; Cintron-Rivera, Jorge; Tariq, Abdul; Nino-Baron, Carlos

2011-04-30T23:59:59.000Z

231

Contrast-Medium-Enhanced Digital Mammography: Contrast vs. Iodine Concentration Phantom Calibration  

SciTech Connect (OSTI)

This work deals with the application of the contrast-medium-enhanced digital subtraction mammography technique in order to calibrate the contrast level in subtracted phantom images as function of iodine concentration to perform dynamic studies of the contrast-medium uptake in the breast. Previously optimized dual-energy temporal subtraction modalities were used (a) to determine radiological parameters for a dynamic clinical study composed of 1 mask+3 post-contrast images limiting the total mean glandular dose to 2.5 mGy, and (b) to perform a contrast vs iodine concentration calibration using a custom-made phantom. Calculated exposure values were applied using a commercial full-field digital mammography unit. Contrast in subtracted phantom images (one mask and one post-CM) is linear as function of iodine concentration, although the sensitivity (contrast per iodine concentration) decreases beyond 8 mg/mL. This calibration seems to apply only to thin and normal thickness breasts.

Rosado-Mendez, I.; Brandan, M. E. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, 04510 DF (Mexico); Villasenor, Y. [Instituto Nacional de Cancerologia (INCan), Av. San Fernando 22, Tlalpan 14080 DF (Mexico); Benitez-Bribiesca, L. [Centro Medico Nacional Siglo XXI, Av. Cuauhtemoc 330, Col. Doctores 06725 DF (Mexico)

2008-08-11T23:59:59.000Z

232

A design study for a medium-scale field demonstration of the viscous barrier technology  

SciTech Connect (OSTI)

This report is the design study for a medium-scale field demonstration of Lawrence Berkeley National Laboratory`s new subsurface containment technology for waste isolation using a new generation of barrier liquids. The test site is located in central California in a quarry owned by the Los Banos Gravel Company in Los Banos, California, in heterogeneous unsaturated deposits of sand, silt, and -ravel typical of many of the and DOE cleanup sites and particularly analogous to the Hanford site. The coals of the field demonstration are (a) to demonstrate the ability to create a continuous subsurface barrier isolating a medium-scale volume (30 ft long by 30 ft wide by 20 ft deep, i.e. 1/10th to 1/8th the size of a buried tank at the Hanford Reservation) in the subsurface, and (b) to demonstrate the continuity, performance, and integrity of the barrier.

Moridis, G. [Lawrence Berkeley National Lab., CA (United States); Yen, P. [Bechtel Corp., San Francisco, CA (United States); Persoff, P.; Finsterle, S.; Williams, P.; Myer, L.; Pruess, K. [Lawrence Berkeley National Lab., CA (United States)

1996-09-01T23:59:59.000Z

233

Quantum noise of white light cavity using double-pumped gain medium  

E-Print Network [OSTI]

Laser interferometric gravitational-wave detectors implement Fabry-Perot cavities to increase their peak sensitivity. However, this is at cost of reducing their detection bandwidth, which origins from the propagation phase delay of the light. The "white-light-cavity" idea, first proposed by Wicht et al. [Optics Communications 134, 431 (1997)], is to circumvent this limitation by introducing anomalous dispersion, using double-pumped gain medium, to compensate for such phase delay. In this article, starting from the Hamiltonian of atom-light interaction, we apply the input-output formalism to evaluate the quantum noise of the system. We find that apart from the additional noise associated with the parametric amplification process noticed by others, the stability condition for the entire system poses an additional constraint. Through surveying the parameter regimes where the gain medium remains stable (not lasing) and stationary, we find that there is no net enhancement of the shot-noise limited sensitivity. The...

Ma, Yiqiu; Zhao, Chunnong; Chen, Yanbei

2015-01-01T23:59:59.000Z

234

Unexpected short- and medium-range atomic structure of sputtered amorphous silicon upon thermal annealing  

SciTech Connect (OSTI)

We investigate the structure of magnetron-sputtered (MS) amorphous silicon (a-Si) prepared under standard deposition conditions and compare this to pure ion-implanted (II) a-Si. The structure of both films is characterized in their as-prepared and thermally annealed states. Significant differences are observed in short- and medium-range order following thermal annealing. Whereas II a-Si undergoes structural relaxation toward a continuous random network, MS a-Si exhibits little change. Cross-sectional transmission electron microscopy reveals the presence of nanopores in the MS film consistent with reduced mass-density. Therefore, the short- and medium-range order of annealed, MS a-Si is tentatively attributed to these pores.

Haberl, B.; McKerracher, I.; Ruffell, S.; Williams, J. S.; Bradby, J. E. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia); Bogle, S. N.; Li, T.; Abelson, J. R. [Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Munroe, P. [Electron Microscope Unit, University of New South Wales, Sydney, NSW 2052 (Australia)

2011-11-01T23:59:59.000Z

235

Kelvin-Helmholtz instability in a strongly coupled dusty plasma medium  

SciTech Connect (OSTI)

The Kelvin-Helmholtz (KH) instability in the context of strongly coupled dusty plasma medium has been investigated. In particular, the role of transverse shear and the compressional acoustic modes in both the linear and nonlinear regimes of the KH instability has been studied. It is observed that in addition to the conventional nonlocal KH instability, there exists a local instability in the strong coupling case. The interplay of the KH mode with this local instability shows up in the simulations as an interesting phenomenon of recurrence in the nonlinear regime. Thus, a cyclic KH instability process is observed to occur. These cyclic events are associated with bursts of activity in terms of transverse and compressional wave generation in the medium.

Tiwari, Sanat Kumar; Das, Amita; Patel, Bhavesh G. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Angom, Dilip [Physical Research Laboratory, Ahmedabad 380 009 (India); Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Physical Research Laboratory, Ahmedabad 380 009 (India)

2012-07-15T23:59:59.000Z

236

A Preliminary Study of Oxidation of Lignin from Rubber Wood to Vanillin in Ionic Liquid Medium  

E-Print Network [OSTI]

In this study, lignin was oxidised to vanillin by means of oxygen in ionic liquid (1,3-dimethylimidazolium methylsulphate) medium. The parameters of the oxidation reaction that have been investigated were the following: concentration of oxygen (5, 10, 15 and 20 ft3 h-1), reaction time (2, 4, 6, 8 and 10 h) and reaction temperature (25, 40, 60, 80 and 100{\\deg}C). The Fourier transform infrared spectroscopy, high performance liquid chromatography and ultraviolet-visible analyses were used to characterise the product. The results revealed vanillin as the product obtained via the oxidation reaction. The optimum parameters of vanillin production were 20 ft3 h-1 of oxygen for 10 h at 100{\\deg}C. In conclusion, 1,3-dimethylimidazolium methylsulphate could be used as an oxidation reaction medium for the production of vanillin from rubber wood lignin.

Shamsuri, A A

2013-01-01T23:59:59.000Z

237

Clean Cities Guide to Alternative Fuel and Advanced Medium- and Heavy-Duty Vehicles (Book)  

SciTech Connect (OSTI)

Today's fleets are increasingly interested in medium-duty and heavy-duty vehicles that use alternative fuels or advanced technologies that can help reduce operating costs, meet emissions requirements, improve fleet sustainability, and support U.S. energy independence. Vehicle and engine manufacturers are responding to this interest with a wide range of options across a steadily growing number of vehicle applications. This guide provides an overview of alternative fuel power systems?including engines, microturbines, electric motors, and fuel cells?and hybrid propulsion systems. The guide also offers a list of individual medium- and heavy-duty vehicle models listed by application, along with associated manufacturer contact information, fuel type(s), power source(s), and related information.

Not Available

2013-08-01T23:59:59.000Z

238

MEDIUM POWER 352 MHZ SOLID STATE PULSED RF AMPLIFIERS FOR THE CERN LINAC4 PROJECT  

E-Print Network [OSTI]

MEDIUM POWER 352 MHZ SOLID STATE PULSED RF AMPLIFIERS FOR THE CERN LINAC4 PROJECT J. Broere, J in the CERN Linac4. The amplifiers are water-cooled and can provide up to 33 kW pulsed RF Power, 1.5 ms pulse RF Power for the debuncher cavity. The concept is based on 1.2 kW RF power modules using the latest 6

Paris-Sud XI, Université de

239

Method for in situ characterization of a medium of dispersed matter in a continuous phase  

DOE Patents [OSTI]

A method is described for the in situ characterization of a medium of a dispersed phase in a continuous phase, including the steps of adding a fluorescent dye to one phase capable of producing fluorescence therein when the fluorescent dye is optically excited, optically exciting the fluorescent dye at a wavelength to produce fluorescence in the one phase, and monitoring the fluorescence to distinguish the continuous phase from the dispersed phase. 2 figs.

Kaufman, E.N.

1995-03-07T23:59:59.000Z

240

Zymomonas with improved ethanol production in medium containing concentrated sugars and acetate  

DOE Patents [OSTI]

Through screening of a Zymomonas mutant library the himA gene was found to be involved in the inhibitory effect of acetate on Zymomonas performance. Xylose-utilizing Zymomonas strains further engineered to reduce activity of the himA gene were found to have increased ethanol production in comparison to a parental strain, when cultured in mixed-sugars medium comprising xylose, and, in particular, in the presence of acetate.

Caimi, Perry G. (Kennett Square, PA); Chou, Yat-Chen (Lakewood, CO); Franden, Mary Ann (Centennial, CO); Knoke, Kyle (Newark, DE); Tao, Luan (Havertown, PA); Viitanen, Paul V. (West Chester, PA); Zhang, Min (Lakewood, CO); Zhang, Yuying (New Hope, PA)

2011-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Method for in situ characterization of a medium of dispersed matter in a continuous phase  

DOE Patents [OSTI]

A method for in situ characterization of a medium of a dispersed phase in a continuous phase, including the steps of adding a fluorescent dye to one phase capable of producing fluorescence therein when the fluorescent dye is optically excited, optically exciting the fluorescent dye at a wavelength to produce fluorescence in the one phase, and monitoring the fluorescence to distinguish the continuous phase from the dispersed phase.

Kaufman, Eric N. (Knoxville, TN)

1995-01-01T23:59:59.000Z

242

The Magnus expansion and the in-medium similarity renormalization group  

SciTech Connect (OSTI)

We present a variant of the in-medium similarity renormalization group(IMSRG) based on the Magnus expansion. In this new variant, the unitary transformation of the IMSRG is constructed explicitly, which allows for the transformation of observables quickly and easily. Additionally, the stiffness of equations encountered by the traditional solution of the IMSRG can be alleviated greatly. We present results and comparisons for the 3d electron gas.

Morris, T. D.; Bogner, S. K. [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48844 (United States)

2014-10-15T23:59:59.000Z

243

Method for encapsulating and isolating hazardous cations, medium for encapsulating and isolating hazardous cations  

DOE Patents [OSTI]

A method for encapsulating hazardous cations is provided comprising supplying a pretreated substrate containing the cations; contacting the substrate with an organo-silane compound to form a coating on the substrate; and allowing the coating to cure. A medium for containing hazardous cations is also provided, comprising a substrate having ion-exchange capacity and a silane-containing coating on the substrate. 3 figs.

Wasserman, S.R.; Anderson, K.B.; Song, K.; Yuchs, S.E.; Marshall, C.L.

1998-04-28T23:59:59.000Z

244

Medium and Heavy-Duty Vehicle Field Evaluations | Department of Energy  

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

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: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion | Department of EnergyDevelopmentTechnologies | Department ofMeasuringofHeavy DutyMedium

245

A Priori Estimates and Regularization for a Class of Porous Medium Equations 1  

E-Print Network [OSTI]

and Robert C. Sharpley Abstract The general class of porous medium equations: @S @t +r \\Delta f(S)u \\Gamma r of saturation problems arise: @S @t +r \\Delta (f(S)u) \\Gamma r \\Delta (k(S)rS) = Q(S) on\\Omega \\Theta (0; T 0 ] (1:1a) with boundary conditions: (f(S)u \\Gamma k(S)rS) \\Delta n = q on @\\Omega \\Theta [0; T 0 ] (1:1b

Sharpley, Robert

246

Automated Demand Response Technology Demonstration Project for Small and Medium Commercial Buildings  

SciTech Connect (OSTI)

Small and medium commercial customers in California make up about 20-25% of electric peak load in California. With the roll out of smart meters to this customer group, which enable granular measurement of electricity consumption, the investor-owned utilities will offer dynamic prices as default tariffs by the end of 2011. Pacific Gas and Electric Company, which successfully deployed Automated Demand Response (AutoDR) Programs to its large commercial and industrial customers, started investigating the same infrastructures application to the small and medium commercial customers. This project aims to identify available technologies suitable for automating demand response for small-medium commercial buildings; to validate the extent to which that technology does what it claims to be able to do; and determine the extent to which customers find the technology useful for DR purpose. Ten sites, enabled by eight vendors, participated in at least four test AutoDR events per site in the summer of 2010. The results showed that while existing technology can reliably receive OpenADR signals and translate them into pre-programmed response strategies, it is likely that better levels of load sheds could be obtained than what is reported here if better understanding of the building systems were developed and the DR response strategies had been carefully designed and optimized for each site.

Page, Janie; Kiliccote, Sila; Dudley, Junqiao Han; Piette, Mary Ann; Chiu, Albert K.; Kellow, Bashar; Koch, Ed; Lipkin, Paul

2011-07-01T23:59:59.000Z

247

Small- and Medium-Sized Commercial Building Monitoring and Controls Needs: A Scoping Study  

SciTech Connect (OSTI)

Buildings consume over 40% of the total energy consumption in the U.S. A significant portion of the energy consumed in buildings is wasted because of the lack of controls or the inability to use existing building automation systems (BASs) properly. Much of the waste occurs because of our inability to manage and controls buildings efficiently. Over 90% of the buildings are either small-size (<5,000 sf) or medium-size (between 5,000 sf and 50,000 sf); these buildings currently do not use BASs to monitor and control their building systems from a central location. According to Commercial Building Energy Consumption Survey (CBECS), about 10% of the buildings in the U.S. use BASs or central controls to manage their building system operations. Buildings that use BASs are typically large (>100,000 sf). Lawrence Berkeley National Laboratory (LBNL), Oak Ridge National Laboratory (ORNL) and Pacific Northwest National Laboratory (PNNL) were asked by the U.S. Department of Energy’s (DOE’s) Building Technologies Program (BTP) to identify monitoring and control needs for small- and medium-sized commercial buildings and recommend possible solutions. This study documents the needs and solutions for small- and medium-sized buildings.

Katipamula, Srinivas; Underhill, Ronald M.; Goddard, James K.; Taasevigen, Danny J.; Piette, M. A.; Granderson, J.; Brown, Rich E.; Lanzisera, Steven M.; Kuruganti, T.

2012-10-31T23:59:59.000Z

248

Heavy quark scattering and quenching in a QCD medium at finite temperature and chemical potential  

E-Print Network [OSTI]

The heavy quark collisional scattering on partons of the quark gluon plasma (QGP) is studied in a QCD medium at finite temperature and chemical potential. We evaluate the effects of finite parton masses and widths, finite temperature $T$ and quark chemical potential $\\mu_q$ on the different elastic cross sections for dynamical quasi-particles (on- and off-shell particles in the QGP medium as described by the dynamical quasi-particles model "DQPM") using the leading order Born diagrams. Our results show clearly the decrease of the $qQ$ and $gQ$ total elastic cross sections when the temperature and the quark chemical potential increase. These effects are amplified for finite $\\mu_q$ at temperatures lower than the corresponding critical temperature $T_c (\\mu_q)$. Using these cross sections we, furthermore, estimate the energy loss and longitudinal and transverse momentum transfers of a heavy quark propagating in a finite temperature and chemical potential medium. Accordingly, we have shown that the transport pro...

Berrehrah, H; Cassing, W; Gossiaux, P B; Aichelin, J

2015-01-01T23:59:59.000Z

249

DYNAMICAL FRICTION IN A GASEOUS MEDIUM WITH A LARGE-SCALE MAGNETIC FIELD  

SciTech Connect (OSTI)

The dynamical friction force experienced by a massive gravitating body moving through a gaseous medium is modified by sufficiently strong large-scale magnetic fields. Using linear perturbation theory, we calculate the structure of the wake generated by, and the gravitational drag force on, a body traveling in a straight-line trajectory in a uniformly magnetized medium. The functional form of the drag force as a function of the Mach number ({identical_to} V{sub 0}/c{sub s} , where V{sub 0} is the velocity of the body and c{sub s} is the sound speed) depends on the strength of the magnetic field and on the angle between the velocity of the perturber and the direction of the magnetic field. In particular, the peak value of the drag force is not near Mach number {approx}1 for a perturber moving in a sufficiently magnetized medium. As a rule of thumb, we may state that for supersonic motion, magnetic fields act to suppress dynamical friction; for subsonic motion, they tend to enhance dynamical friction. For perturbers moving along the magnetic field lines, the drag force at some subsonic Mach numbers may be stronger than at supersonic velocities. We also mention the relevance of our findings to black hole coalescence in galactic nuclei.

Sanchez-Salcedo, F. J., E-mail: jsanchez@astroscu.unam.mx [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, 04510 Mexico City (Mexico)

2012-02-01T23:59:59.000Z

250

Radio-wave propagation in the non-Gaussian interstellar medium  

E-Print Network [OSTI]

Radio waves propagating from distant pulsars in the interstellar medium (ISM), are refracted by electron density inhomogeneities, so that the intensity of observed pulses fluctuates with time. The theory relating the observed pulse time-shapes to the electron-density correlation function has developed for 30 years, however, two puzzles have remained. First, observational scaling of pulse broadening with the pulsar distance is anomalously strong; it is consistent with the standard model only when non-uniform statistics of electron fluctuations along the line of sight are assumed. Second, the observed pulse shapes are consistent with the standard model only when the scattering material is concentrated in a narrow slab between the pulsar and the Earth. We propose that both paradoxes are resolved at once if one assumes stationary and uniform, but non-Gaussian statistics of the electron-density distribution. Such statistics must be of Levy type, and the propagating ray should exhibit a Levy flight. We propose that a natural realization of such statistics may be provided by the interstellar medium with random electron-density discontinuities. We develop a theory of wave propagation in such a non-Gaussian random medium, and demonstrate its good agreement with observations. The qualitative introduction of the approach and the resolution of the anomalous-scaling paradox was presented earlier in [PRL 91, 131101 (2003); ApJ 584, 791 (2003)].

Stanislav Boldyrev; Carl R. Gwinn

2005-08-02T23:59:59.000Z

251

Diffusion of $?_c$ in hot hadronic medium and its impact on $?_c/D$ ratio  

E-Print Network [OSTI]

The drag and diffusion coefficients of the $\\Lambda_c(2286$ MeV) have been evaluated in the hadronic medium which is expected to be formed in the later stages of the evolving fire ball produced in heavy ion collisions at RHIC and LHC energies. The interactions between the $\\Lambda_c$ and the hadrons in the medium have been derived from an effective hadronic Lagrangian as well as from the scattering lengths, obtained in the framework of heavy baryon chiral perturbation theory (HB$\\chi$PT). In both the approaches, the magnitude of the transport coefficients are turn out to be significant. A larger value is obtained in the former approach with respect to the latter. Significant values of the coefficients indicate substantial amount of interaction of the $\\Lambda_c$ with the hadronic thermal bath. Furthermore, the transport coefficients of the $\\Lambda_c$ is found to be different from the transport coefficients of $D$ meson. Present study indicates that the hadronic medium has a significant impact on the $\\Lambda_c/D$ ratio in heavy ion collisions.

Sabyasachi Ghosh; Santosh K. Das; Vincenzo Greco; Sourav Sarkar; Jan-e Alam

2014-09-19T23:59:59.000Z

252

Characterization of In-Use Medium Duty Electric Vehicle Driving and Charging Behavior: Preprint  

SciTech Connect (OSTI)

The U.S. Department of Energy's American Recovery and Reinvestment Act (ARRA) deployment and demonstration projects are helping to commercialize technologies for all-electric vehicles (EVs). Under the ARRA program, data from Smith Electric and Navistar medium duty EVs have been collected, compiled, and analyzed in an effort to quantify the impacts of these new technologies. Over a period of three years, the National Renewable Energy Laboratory (NREL) has compiled data from over 250 Smith Newton EVs for a total of over 100,000 days of in-use operation. Similarly, data have been collected from over 100 Navistar eStar vehicles, with over 15,000 operating days having been analyzed. NREL has analyzed a combined total of over 4 million kilometers of driving and 1 million hours of charging data for commercial operating medium duty EVs. In this paper, the authors present an overview of medium duty EV operating and charging behavior based on in-use data collected from both Smith and Navistar vehicles operating in the United States. Specifically, this paper provides an introduction to the specifications and configurations of the vehicles examined; discusses the approach and methodology of data collection and analysis, and presents detailed results regarding daily driving and charging behavior. In addition, trends observed over the course of multiple years of data collection are examined, and conclusions are drawn about early deployment behavior and ongoing adjustments due to new and improving technology. Results and metrics such as average daily driving distance, route aggressiveness, charging frequency, and liter per kilometer diesel equivalent fuel consumption are documented and discussed.

Duran, A.; Ragatz, A.; Prohaska, R.; Kelly, K.; Walkowicz, K.

2014-11-01T23:59:59.000Z

253

Value of medium range weather forecasts in the improvement of seasonal hydrologic prediction skill  

SciTech Connect (OSTI)

We investigated the contribution of medium range weather forecasts with lead times up to 14 days to seasonal hydrologic prediction skill over the Conterminous United States (CONUS). Three different Ensemble Streamflow Prediction (ESP)-based experiments were performed for the period 1980-2003 using the Variable Infiltration Capacity (VIC) hydrology model to generate forecasts of monthly runoff and soil moisture (SM) at lead-1 (first month of the forecast period) to lead-3. The first experiment (ESP) used a resampling from the retrospective period 1980-2003 and represented full climatological uncertainty for the entire forecast period. In the second and third experiments, the first 14 days of each ESP ensemble member were replaced by either observations (perfect 14-day forecast) or by a deterministic 14-day weather forecast. We used Spearman rank correlations of forecasts and observations as the forecast skill score. We estimated the potential and actual improvement in baseline skill as the difference between the skill of experiments 2 and 3 relative to ESP, respectively. We found that useful runoff and SM forecast skill at lead-1 to -3 months can be obtained by exploiting medium range weather forecast skill in conjunction with the skill derived by the knowledge of initial hydrologic conditions. Potential improvement in baseline skill by using medium range weather forecasts, for runoff (SM) forecasts generally varies from 0 to 0.8 (0 to 0.5) as measured by differences in correlations, with actual improvement generally from 0 to 0.8 of the potential improvement. With some exceptions, most of the improvement in runoff is for lead-1 forecasts, although some improvement in SM was achieved at lead-2.

Shukla, Shraddhanand; Voisin, Nathalie; Lettenmaier, D. P.

2012-08-15T23:59:59.000Z

254

Convection induced by radiative cooling of a layer of participating medium  

SciTech Connect (OSTI)

Simulations and experiments have been conducted to study the effect of radiative cooling on natural convection in a horizontal layer of a participating medium enclosed between isothermal opaque wall and radiatively transparent wall and exposed to a cold background. The study is of relevance to a nocturnal boundary layer under clear and calm conditions. The focus of the study is to capture the onset of convection caused by radiative cooling. The experiments have been designed to mimic the atmospheric radiative boundary conditions, and hence decoupling convection and radiation boundary conditions. Planck number Pl and optical thickness of the layer ?{sub H} are the two important parameters that govern the interaction between radiation and convection. The radiation-convection coupling is a strong function of length scale. Convection sets up within first few seconds for all the experiments. Strong plume like convection is observed for the experimental conditions used in the present study. Both simulations and experiments confirm that radiative cooling increases substantially with decrease in emissivity of the bottom wall. Radiative cooling is strongly influenced by the nongray nature of the participating medium, especially when strong emission from the medium escapes to space, in the window region of the atmosphere. Accurate representation of radiative properties is critical. Linear stability analysis of onset of convection indicates that radiation stabilizes convection as Pl decreases. The observations are similar to the case of Rayleigh Bénard convection in a radiating gas. However, for both experimental and numerical conditions, the observed Rayleigh numbers are much greater than the critical Rayleigh number. To conclude, the role of radiation is to drive and sustain convection in the unstable layer.

Prasanna, Swaminathan, E-mail: prasannaswam@gmail.com [Laboratoire EM2C, CNRS UPR 288 92295, Chatenay-Malabry, France and Ecole Centrale Paris, Grande Voie des Vignes 92295, Chatenay-Malabry (France)] [Laboratoire EM2C, CNRS UPR 288 92295, Chatenay-Malabry, France and Ecole Centrale Paris, Grande Voie des Vignes 92295, Chatenay-Malabry (France); Venkateshan, S. P., E-mail: spv@iitm.ac.in [HTTP Laboratory, Department of Mechanical Engineering IIT Madras, Chennai (India)

2014-05-15T23:59:59.000Z

255

Production of Clostridium difficile toxin in a medium totally free of both animal and dairy proteins or digests  

E-Print Network [OSTI]

In the hope of developing a vaccine against Clostridium difficile based on its toxin(s), we have developed a fermentation medium for the bacterium that results in the formation of Toxin A and contains no meat or dairy ...

Demain, Arnold L.

256

Probing the isospin dependence of the in-medium nucleon-nucleon cross sections with radioactive beams  

E-Print Network [OSTI]

Within a transport model we search for potential probes of the isospin dependence of the in-medium nucleon-nucleon (NN) cross sections. Traditional measures of the nuclear stopping power are found sensitive to the magnitude but they are ambiguous for determining the isospin dependence of the in-medium NN cross sections. It is shown that isospin tracers, such as the neutron/proton ratio of free nucleons, at backward rapidities/angles in nuclear reactions induced by radioactive beams in inverse kinematics is a sensitive probe of the isospin dependence of the in-medium NN cross sections. At forward rapidities/angles, on the other hand, they are more sensitive to the density dependence of the symmetry energy. Measurements of the rapidity/angular dependence of the isospin transport in nuclear reactions will enable a better understanding of the isospin dependence of in-medium nuclear effective interactions.

Bao-An Li; Pawel Danielewicz; William G. Lynch

2005-03-13T23:59:59.000Z

257

Probing the isospin dependence of the in-medium nucleon-nucleon cross sections with radioactive beams  

SciTech Connect (OSTI)

Within a transport model we search for potential probes of the isospin dependence of the in-medium nucleon-nucleon (NN ) cross sections. Traditional measures of the nuclear stopping power are found to be sensitive to the magnitude but they are ambiguous for determining the isospin dependence of the in-medium NN cross sections. It is shown that isospin tracers, such as the neutron/proton ratio of free nucleons, at backward rapidities and angles in nuclear reactions induced by radioactive beams in inverse kinematics are a sensitive probe of the isospin dependence of the in-medium NN cross sections. At forward rapidities and angles, in contrast, they are more sensitive to the density dependence of the symmetry energy. Measurements of the rapidity and angular dependence of the isospin transport in nuclear reactions will enable a better understanding of the isospin dependence of in-medium nuclear effective interactions.

Li Baoan [National Superconducting Cyclotron Laboratory and Department of Physics, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Chemistry and Physics, Post Office Box 419, Arkansas State University, State University, Arkansas 72467-0419 (United States); Danielewicz, Pawel; Lynch, William G. [National Superconducting Cyclotron Laboratory and Department of Physics, Michigan State University, East Lansing, Michigan 48824 (United States)

2005-05-01T23:59:59.000Z

258

Orthopositronium-orthopositronium scattering using the close-coupling approximation at medium energies  

SciTech Connect (OSTI)

Elastic and excitation (single and double) cross sections (n{<=}3) of orthopositronium-orthopositronium (o-Ps-o-Ps) scattering system are predicted using eigenstate close-coupling approximation at medium energies. The partial wave cross sections have shown a peculiar feature. The static exchange results and other inelastic cross sections for even parity transitions only survive for even values of partial wave and vice versa like Born-Oppenheimer (BO) cross sections. To the best of our knowledge, this feature has not been noticed for other systems. Our results are nearly convergent with added eigenstates and elastic and excitation cross sections are compared with their corresponding BO predictions.

Chakraborty, Sumana; Ghosh, A. S. [Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700 032 (India)

2005-11-15T23:59:59.000Z

259

Effect of nucleon and hadron structure changes in-medium and its impact on observables  

SciTech Connect (OSTI)

We study the effect of hadron structure changes in a nuclear medium using the quark-meson coupling (QMC) model. The QMC model is based on a mean field description of non-overlapping nucleon (or baryon) bags bound by the self-consistent exchange of scalar and vector mesons in the isoscalar and isovector channels. The model is extended to investigate the properties of finite nuclei, in which, using the Born-Oppenheimer approximation to describe the interacting quark-meson system, one can derive the effective equation of motion for the nucleon (or baryon), as well as the self-consistent equations for the meson mean fields.

K. Saito; K. Tsushima; A.W. Thomas

2005-07-05T23:59:59.000Z

260

Tests of Lorentz and CPT Violation in the Medium Baseline Reactor Antineutrino Experiment  

E-Print Network [OSTI]

Tests of Lorentz and CPT violation in the medium baseline reactor antineutrino experiment are presented in the framework of the Standard Model Extension (SME). Both the spectral distortion and sidereal variation are employed to derive the limits of Lorentz violation (LV) coefficients. We do the numerical analysis of the sensitivity of LV coefficients by taking the Jiangmen Underground Neutrino Observatory (JUNO) as an illustration, which can improve the sensitivity by more than two orders of magnitude compared with the current limits from reactor antineutrino experiments.

Yu-Feng Li; Zhen-hua Zhao

2014-11-21T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Analytical Green's function of the radiative transfer radiance for the infinite medium  

SciTech Connect (OSTI)

An analytical solution of the radiative transfer equation for the radiance caused by an isotropic source which is located in an infinitely extended medium was derived using the P{sub N} method. The results were compared with Monte Carlo simulations and excellent agreement was found. In addition, the radiance of the SP{sub N} approximation for the same geometry was derived. Comparison with Monte Carlo simulations showed that the SP{sub N} radiance, although being more exact than the radiance derived from diffusion theory, has relatively large errors in many relevant cases.

Liemert, Andre; Kienle, Alwin [Institut fuer Lasertechnologien in der Medizin und Messtechnik, Helmholtzstrasse12, D-89081 Ulm (Germany)

2011-03-15T23:59:59.000Z

262

Integrating 3D and 2D computer generated imagery for the comics medium  

E-Print Network [OSTI]

medium, while still taking advantage of the new technology. iv DEDICATION For my grandmother, Maria Reyes Torres March 10, 1927 ? August 6, 2002 who taught me that a few sheets of paper folded in half can be a comic book v TABLE OF CONTENTS........................................ 52 viii FIGURE 21 Example panels from Max Comic?s U.S. War Machine 2.0...................... 54 22 Comparison of an initial storyboard to the finished page.......................... 58 23 Initial designs for Maria, her teacher, and the snow...

DeLuna, Ruben

2005-02-17T23:59:59.000Z

263

Effects of Isospin Asymmetry and In-Medium Corrections on Balance Energy  

E-Print Network [OSTI]

The effects of an isospin asymmetry and in-medium corrections to the nucleon collision cross section on the balance energy are explored. The BUU model for intermediate energy heavy-ion collisions is used with isospin-dependent mean fields to calculate the balance energies of 58Fe + 58Fe and 58Ni + 58Ni for a range of impact parameters. We find that we are able to reproduce the impact parameter dependence of the balance energy, and the sign (but not the magnitude) of the shift in balance balance energy as a function of isospin asymmetry.

Frank Daffin; Wolfgang Bauer

1998-09-09T23:59:59.000Z

264

Tuning thermal mismatch between turbine rotor parts with a thermal medium  

DOE Patents [OSTI]

In a turbine rotor, an aft shaft wheel and the final-stage wheel of the rotor are coupled together, including by a rabbeted joint. During shutdown and startup of the turbine, a thermal mismatch between the aft shaft wheel and final-stage wheel is avoided by respectively heating and cooling the aft shaft wheel to maintain the thermal mismatch within acceptable limits, thereby avoiding opening of the rabbeted joint and the potential for unbalancing the rotor and rotor vibration. The thermal medium may be supplied by piping in the aft bearing cavity into the cavity between the forward closure plate and the aft shaft wheel.

Schmidt, Mark Christopher (Niskayuna, NY)

2001-01-01T23:59:59.000Z

265

K+ Total Cross-Sections on C-12 and Medium Effects in Nuclei  

E-Print Network [OSTI]

2 target was determined in an independent experi- ment using a neutron beam from the Brookhaven High Flux Beam Reactor, in which 2.224 MeV p rays from the iH(n, p)~H reaction were detected with a germanium de- tector. It was found that a sample..., with differing nucleon densities, might reveal medium effects. Such a comparison was originally suggested by Siegel, Kaufmann, and Gibbs [7]. Their suggestions strongly motivated the present experi- ment which was conceived to test their predictions...

Krauss, R. A.; Alster, J.; Ashery, D.; Bart, S.; Chrien, R. E.; Hiebert, John C.; Johnson, R. R.; Kishimoto, T.; Mardor, I.; Mardor, Y.; Moinester, M. A.; Olshevsky, R.; Piasetzky, E.; Pile, P. H.; Sawafta, R.; Stearns, R. L.; Sutter, R. J.; WEISS, R.; Yavin, A. I.

1992-01-01T23:59:59.000Z

266

Qubit transfer between photons at telecom and visible wavelengths in a slow-light atomic medium  

E-Print Network [OSTI]

We propose a method that enables efficient conversion of quantum information frequency between different regions of spectrum of light based on recently demonstrated strong parametric coupling between two narrow-band single-photon pulses propagating in a slow-light atomic medium [1]. We show that an input qubit at telecom wavelength is transformed into another at visible domain in a lossless and shape-conserving manner while keeping the initial quantum coherence and entanglement. These transformations can be realized with a quantum efficiency close to its maximum value.

A. Gogyan

2009-12-08T23:59:59.000Z

267

Transient recovery voltage considerations in the application of medium voltage circuit breakers  

SciTech Connect (OSTI)

Medium Voltage Circuit Breakers can fail to interrupt 3-phase fault currents when power systems have Transient Recovery Voltage (TRV) characteristics which exceed the rating of the circuit breaker. This paper examines the application of 13.8kV generation and load switchgear for an oil refinery in which circuit parameters as originally designed would have exceeded the 13.8kV circuit breakers TRV ratings had corrective measures not been taken. This paper illustrates this case and discusses the basis of TRV, how TRV is assessed, and alternative actions taken to bring circuits to within the 13.8 kV circuit breaker ratings.

Swindler, D.L.; Schwartz, P.; Hamer, P.S.; Lambert, S.R.

1995-12-31T23:59:59.000Z

268

Exploration of the comics medium developed for use on the internet  

E-Print Network [OSTI]

of a given site or made available to be downloaded. Finally, in what is possibly the greatest separation from the two-dimensionality of the printed medium, the advancement of V R M L (virtual reality markup language) on the internet allows for a... as the speed of the internet connection, could have a dramatically different experience within a common web site. It is evident that the internet, much like traditional printed work, has its own limita tions. Ultimately, however, it also has ever...

Piana, Brian James

2012-06-07T23:59:59.000Z

269

Spatial correction factors for YALINA Booster facility loaded with medium and low enriched fuels  

SciTech Connect (OSTI)

The Bell and Glasstone spatial correction factor is used in analyses of subcritical assemblies to correct the experimental reactivity as function of the detector position. Besides the detector position, several other parameters affect the correction factor: the energy weighting function of the detector, the detector size, the energy-angle distribution of source neutrons, and the reactivity of the subcritical assembly. This work focuses on the dependency of the correction factor on the detector material and it investigates the YALINA Booster subcritical assembly loaded with medium (36%) and low (10%) enriched fuels. (authors)

Talamo, A.; Gohar, Y. [Argonne National Laboratory, 9700 S. Cass Ave, Argonne, IL 60439 (United States); Bournos, V.; Fokov, Y.; Kiyavitskaya, H.; Routkovskaya, C. [Joint Inst. for Power and Nuclear Research-Sosny, 99 Academician A.K.Krasin Str, Minsk 220109 (Belarus)

2012-07-01T23:59:59.000Z

270

Sphere penetration by impact in a granular medium: A collisional process  

E-Print Network [OSTI]

The penetration by a gravity driven impact of a solid sphere into a granular medium is studied by two-dimensional simulations. The scaling laws observed experimentally for both the final penetration depth and the stopping time with the relevant physical parameters are here recovered numerically without the consideration of any solid friction. Collisional processes are thus found as essential in explaining the physics of the qualitatively observed phenomena whereas frictional processes can only be considered as secondary effects in the granular penetration by impact.

Antoine Seguin; Yann Bertho; Philippe Gondret; Jerome Crassous

2009-11-26T23:59:59.000Z

271

Ridge, Bulk, and Medium Response: How to Kill Models and Learn Something in the Process  

E-Print Network [OSTI]

In these proceedings, we highlight experimental data (published and preliminary) related to jet quenching and the response of the medium to this deposited energy. Signatures in two- and three- particle hadron correlations indicate interesting structures near the trigger particle in azimuth and over a broad range in pseudo-rapidity, often termed "the ridge", and conical-like structures separated in azimuth opposite to the trigger particle. We review numerous theoretical interpretations of the ridge in particular with a critical eye for the key properties that allow one to discriminate between, or rule out, certain physical pictures and models (and hopefully learn something in the process).

J. L. Nagle

2009-09-15T23:59:59.000Z

272

Spatial and temporal climate variations influencing medium-range temperature predictions over south-central European Russia  

E-Print Network [OSTI]

SPATIAL AND TEMPORAL CLIMATE VARIATIONS INFLUENCING MEDIUM-RANGE TEMPERATURE PREDICTIONS OVER SOUTH-CENTRAL EUROPEAN RUSSIA A Thesis by JEFFREY EDWARD JOHNSON Submitted to the Office of Graduate Studies of Texas A&M University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1990 Major Subject: Meteorology SPATIAL AND TEMPORAL CLIMATE VARIATIONS INFLUENCING MEDIUM-RANGE TEMPERATURE PREDICTIONS OVER SOUTH-CENTRAL EUROPEAN RUSSIA A Thesis JEFFREY EDWARD...

Johnson, Jeffrey Edward

2012-06-07T23:59:59.000Z

273

In-medium NN cross sections determined from stopping and collective flow in intermediate-energy heavy-ion collisions  

E-Print Network [OSTI]

In-medium nucleon-nucleon scattering cross sections are explored by comparing results of quantum molecular dynamics simulations to data on stopping and on elliptic and directed flow in intermediate-energy heavy-ion collisions. The comparison points to in-medium cross sections which are suppressed at low energies but not at higher energies. Positive correlations are found between the degree of stopping and the magnitudes of elliptic and directed flows.

Zhang, Y; Li, Z; Danielewicz, Pawel; Li, Zhuxia; Zhang, Yingxun

2007-01-01T23:59:59.000Z

274

In-medium NN cross sections determined from stopping and collective flow in intermediate-energy heavy-ion collisions  

E-Print Network [OSTI]

In-medium nucleon-nucleon scattering cross sections are explored by comparing results of quantum molecular dynamics simulations to data on stopping and on elliptic and directed flow in intermediate-energy heavy-ion collisions. The comparison points to in-medium cross sections which are suppressed at low energies but not at higher energies. Positive correlations are found between the degree of stopping and the magnitudes of elliptic and directed flows.

Yingxun Zhang; Zhuxia Li; Pawel Danielewicz

2007-03-14T23:59:59.000Z

275

Ultraslow Wave Nuclear Burning of Uranium-Plutonium Fissile Medium on Epithermal Neutrons  

E-Print Network [OSTI]

For a fissile medium, originally consisting of uranium-238, the investigation of fulfillment of the wave burning criterion in a wide range of neutron energies is conducted for the first time, and a possibility of wave nuclear burning not only in the region of fast neutrons, but also for cold, epithermal and resonance ones is discovered for the first time. For the first time the results of the investigation of the Feoktistov criterion fulfillment for a fissile medium, originally consisting of uranium-238 dioxide with enrichments 4.38%, 2.00%, 1.00%, 0.71% and 0.50% with respect to uranium-235, in the region of neutron energies 0.015-10.0eV are presented. These results indicate a possibility of ultraslow wave neutron-nuclear burning mode realization in the uranium-plutonium media, originally (before the wave initiation by external neutron source) having enrichments with respect to uranium-235, corresponding to the subcritical state, in the regions of cold, thermal, epithermal and resonance neutrons. In order to validate the conclusions, based on the slow wave neutron-nuclear burning criterion fulfillment depending on the neutron energy, the numerical modeling of ultraslow wave neutron-nuclear burning of a natural uranium in the epithermal region of neutron energies (0.1-7.0eV) was conducted for the first time. The presented simulated results indicate the realization of the ultraslow wave neutron-nuclear burning of the natural uranium for the epithermal neutrons.

V. D. Rusov; V. A. Tarasov; M. V. Eingorn; S. A. Chernezhenko; A. A. Kakaev; V. M. Vashchenko; M. E. Beglaryan

2014-09-29T23:59:59.000Z

276

P-986 Letter of Intent: Medium-Energy Antiproton Physics at Fermilab  

SciTech Connect (OSTI)

Fermilab has long had the world's most intense antiproton source. Despite this, the opportunities for medium-energy antiproton physics at Fermilab have been limited in the past and - with the antiproton source now exclusively dedicated to serving the needs of the Tevatron Collider - are currently nonexistent. The anticipated shutdown of the Tevatron in 2010 presents the opportunity for a world-leading medium-energy antiproton program. We summarize the current status of the Fermilab antiproton facility and review some physics topics for which the experiment we propose could make the world's best measurements. Among these, the ones with the clearest potential for high impact and visibility are in the area of charm mixing and CP violation. Continued running of the Antiproton Source following the shutdown of the Tevatron is thus one of the simplest ways that Fermilab can restore a degree of breadth to its future research program. The impact on the rest of the program will be minor. We request a small amount of effort over the coming months in order to assess these issues in more detail.

Asner, David M.; /Carleton U.; Phillips, Thomas J.; /Duke U.; Apollinari, Giorgio; Broemmelsiek, Daniel R.; Brown, Charles N.; Christian, David C.; Derwent, Paul; Gollwitzer, Keith; Hahn, Alan; Papadimitriou, Vaia; Stefanski, Ray; /Fermilab /INFN, Ferrara /Hbar Technol., West Chicago /IIT, Chicago /CHEP, Taegu /Luther Coll. /Michigan U. /Northwestern U. /Notre Dame U. /St. Xavier U., Chicago

2009-02-05T23:59:59.000Z

277

Market Assessment of Biomass Gasification and Combustion Technology for Small- and Medium-Scale Applications  

SciTech Connect (OSTI)

This report provides a market assessment of gasification and direct combustion technologies that use wood and agricultural resources to generate heat, power, or combined heat and power (CHP) for small- to medium-scale applications. It contains a brief overview of wood and agricultural resources in the U.S.; a description and discussion of gasification and combustion conversion technologies that utilize solid biomass to generate heat, power, and CHP; an assessment of the commercial status of gasification and combustion technologies; a summary of gasification and combustion system economics; a discussion of the market potential for small- to medium-scale gasification and combustion systems; and an inventory of direct combustion system suppliers and gasification technology companies. The report indicates that while direct combustion and close-coupled gasification boiler systems used to generate heat, power, or CHP are commercially available from a number of manufacturers, two-stage gasification systems are largely in development, with a number of technologies currently in demonstration. The report also cites the need for a searchable, comprehensive database of operating combustion and gasification systems that generate heat, power, or CHP built in the U.S., as well as a national assessment of the market potential for the systems.

Peterson, D.; Haase, S.

2009-07-01T23:59:59.000Z

278

Markets for low- and medium-Btu coal gasification: an analysis of 13 site specific studies  

SciTech Connect (OSTI)

In 1978 the US Department of Energy (DOE), through its Office of Resource Applications, developed a commercialization plan for low- and medium-Btu coal gasification. Several initial steps have been taken in that process, including a comprehensive study of industrial markets, issuance of a Notice of Program Interest, and funding of proposals under the Alternate Fuels Legislation (P.L. 96-126). To assist it in the further development and administration of the commercialization plan, the Office of Resource Applications has asked Booz, Allen and Hamilton to assess the market prospects for low- and medium-Btu coal gasification. This report covers the detailed findings of the study. Following the introduction which discusses the purpose of the study, approach used for the assignment and current market attitudes on coal gasification, there are three chapters on: systems configurations and applications; economic and finanical attractiveness; and summary of management decisions based on feasibility study results. The final chapter briefly assesses the management decisions. The general consensus seems to be that coal gasification is a technology that will be attractive in the future but is marginal now. 6 figures, 5 tables.

Not Available

1981-09-01T23:59:59.000Z

279

Towards Decentralized Trading: A Topological Investigation of the Dutch Medium and Low Voltage Grids  

E-Print Network [OSTI]

The traditional Power Grid has been designed in a hierarchical fashion, with Energy pushed from the large scale production facilities towards the end users. But with the increasing availability of micro and medium scale generating facilities, the situation is changing. Many end users can now produce energy and share it over the Power Grid. Naturally, end users need to have incentives to do so and might want to be able to act in an open decentralized energy market. In the present work, we offer a novel analysis of the Medium and Low Voltage Power Grids of the North Netherlands using statistical tools from the Complex Network Analysis field. We use a weighted model based on actual Grid data and propose a set of statistical measures to evaluate the adequacy of the current infrastructure for a decentralized energy market. Further, we use the insight gained by the analysis to propose parameters that tie the statistical topological measures to economic factors that might influence the attractiveness to the end user...

Pagani, Giuliano Andrea

2011-01-01T23:59:59.000Z

280

In-medium effects for nuclear matter in the Fermi energy domain  

E-Print Network [OSTI]

We study nuclear stopping in central collisions for heavy-ion induced reactions in the Fermi energy domain, between $15$ and $100$ A\\,\\textrm{MeV}. Using the large dataset of exclusive measurements provided by the $4\\pi$ array \\emph{INDRA}, we determine the relative degree of stopping as a function of system mass and bombarding energy. We show that the stopping can be directly related to the transport properties in the nuclear medium. By looking specifically at free nucleons (here protons), we present for the first time a comprehensive body of experimental results concerning the mean free path, the nucleon-nucleon cross-section and in-medium effects in nuclear matter. It is shown that the mean free path exhibits a maximum at $\\lambda_{NN}=9.5 \\pm 2$ \\textrm{fm}, around $E_{inc}=35-40$ A\\,\\textrm{MeV} incident energy and decreases toward an asymptotic value $\\lambda_{NN}= 4.5 \\pm 1$ \\textrm{fm} at $E_{inc} = 100$ A\\,\\textrm{MeV}. After accounting for Pauli blocking of elastic nucleon-nucleon collisions, it is ...

Lopez, O; Lehaut, G; Borderie, B; Rivet, M F; Bougault, R; Galichet, E; Guinet, D; Neindre, N Le; Marini, P; Napolitani, P; Pârlog, M; Rosato, E; Spadaccini, G; Vient, E; Vigilante, M

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Theoretical and experimental investigation of thermohydrologic processes in a partially saturated, fractured porous medium  

SciTech Connect (OSTI)

The performance of a geologic repository for high-level nuclear waste will be influenced to a large degree by thermohydrologic phenomena created by the emplacement of heat-generating radioactive waste. The importance of these phenomena is manifest in that they can greatly affect the movement of moisture and the resulting transport of radionuclides from the repository. Thus, these phenomena must be well understood prior to a definitive assessment of a potential repository site. An investigation has been undertaken along three separate avenues of analysis: (i) laboratory experiments, (ii) mathematical models, and (iii) similitude analysis. A summary of accomplishments to date is as follows. (1) A review of the literature on the theory of heat and mass transfer in partially saturated porous medium. (2) A development of the governing conservation and constitutive equations. (3) A development of a dimensionless form of the governing equations. (4) A numerical study of the importance and sensitivity of flow to a set of dimensionless groups. (5) A survey and evaluation of experimental measurement techniques. (6) Execution of laboratory experiments of nonisothermal flow in a porous medium with a simulated fracture.

Green, R.T.; Manteufel, R.D. [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Regulatory Applications; Dodge, F.T.; Svedeman, S.J. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

1993-07-01T23:59:59.000Z

282

The effect of magnetic field on copper in various corrosive medium  

SciTech Connect (OSTI)

The effect of applied magnetic field on the corrosion behaviour of copper within various corrosive medium is investigated. The copper coupon is immersed in 0.5 M HCl, 0.5 M NaCl and 0.5 M NaOH with or without applying up to 40 mT magnetic fields for 24 hours. The weight loss of copper coupon in HCl increased up to 96.56% with applied magnetic fields. However, in NaOH medium, only 33.33% more weight loss was observed and no difference were observed for coupons in NaCl when magnetic field is applied. This observation indicates that corrosion behaviour in HCl and NaOH is controlled by mass transport that can be influenced by the induced magneto hydrodynamics effect when magnetic field is applied. There was no change in weight loss of copper in NaCl when magnetic field is applied because the corrosion mechanism of copper in NaCl is governed by electron charge transfer.

Ang, L. Y.; Othman, N. K.; Jalar, A. [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Ismail, I. [Advanced Materials and Nanotechnology Laboratory, Institute of Advanced Technology (ITMA), Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia)

2014-09-03T23:59:59.000Z

283

Toward understanding the thermodynamics of TALSPEAK process. Medium effects on actinide complexation  

SciTech Connect (OSTI)

The ingenious combination of lactate and diethylenetriamine-N,N,N’,N”,N”-pentaacetic acid (DTPA) as an aqueous actinide-complexing medium forms the basis of the successful separation of americium and curium from lanthanides known as the TALSPEAK process. While numerous reports in the prior literature have focused on the optimization of this solvent extraction system, considerably less attention has been devoted to the understanding of the basic thermodynamic features of the complex fluids responsible for the separation. The available thermochemical information of both lactate and DTPA protonation and metal complexation reactions are representative of the behavior of these ions under idealized conditions. Our previous studies of medium effects on lactate protonation suggest that significant departures from the speciation predicted based on reported thermodynamic values should be expected in the TALSPEAK aqueous environment. Thermodynamic parameters describing the separation chemistry of this process thus require further examination at conditions significantly removed from conventional ideal systems commonly employed in fundamental solution chemistry. Such thermodynamic characterization is the key to predictive modelling of TALSPEAK. Improved understanding will, in principle, allow process technologists to more efficiently respond to off-normal conditions during large scale process operation. In this report, the results of calorimetric and potentiometric investigations of the effects of aqueous electrolytes on the thermodynamic parameters for lactate protonation and lactate complexation of americium and neodymium will be presented. Studies on the lactate protonation equilibrium will clearly illustrate distinct thermodynamic variations between strong electrolyte aqueous systems and buffered lactate environment.

Peter R Zalupski; Leigh R Martin; Ken Nash; Yoshinobu Nakamura; Masahiko Yamamoto

2009-07-01T23:59:59.000Z

284

PHYSICAL CONDITIONS IN BARNARD'S LOOP, COMPONENTS OF THE ORION-ERIDANUS BUBBLE, AND IMPLICATIONS FOR THE WARM IONIZED MEDIUM COMPONENT OF THE INTERSTELLAR MEDIUM  

SciTech Connect (OSTI)

We have supplemented existing spectra of Barnard's Loop with high accuracy spectrophotometry of one new position. Cloudy photoionization models were calculated for a variety of ionization parameters and stellar temperatures and compared with the observations. After testing the procedure with recent observations of M43, we establish that Barnard's Loop is photoionized by four candidate ionizing stars, but agreement between the models and observations is only possible if Barnard's Loop is enhanced in heavy elements by about a factor of 1.4. Barnard's Loop is very similar in properties to the brightest components of the Orion-Eridanus Bubble and the warm ionized medium (WIM). We are able to establish models that bound the range populated in low-ionization color-color diagrams (I([S II])/I(H{alpha}) versus I([N II])/I(H{alpha})) using only a limited range of ionization parameters and stellar temperatures. Previously established variations in the relative abundance of heavy elements render uncertain the most common method of determining electron temperatures for components of the Orion-Eridanus Bubble and the WIM based only on the I([N II])/I(H{alpha}) ratio, although we confirm that the lowest surface brightness components of the WIM are on average of higher electron temperature. The electron temperatures for a few high surface brightness WIM components determined by direct methods are comparable to those of classical bright H II regions. In contrast, the low surface brightness H II regions studied by the Wisconsin H{alpha} Mapper are of lower temperatures than the classical bright H II regions.

O'Dell, C. R. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Ferland, G. J. [Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506 (United States); Porter, R. L. [Department of Physics and Astronomy and Center for Simulational Physics, University of Georgia at Athens, Athens, GA 30602-2451 (United States); Van Hoof, P. A. M. [Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels (Belgium)

2011-05-20T23:59:59.000Z

285

Enhancement of the visibility of objects located below the surface of a scattering medium  

DOE Patents [OSTI]

Techniques are provided for enhancing the visibility of objects located below the surface of a scattering medium such as tissue, water and smoke. Examples of such an object include a vein located below the skin, a mine located below the surface of the sea and a human in a location covered by smoke. The enhancement of the image contrast of a subsurface structure is based on the utilization of structured illumination. In the specific application of this invention to image the veins in the arm or other part of the body, the issue of how to control the intensity of the image of a metal object (such as a needle) that must be inserted into the vein is also addressed.

Demos, Stavros

2013-11-19T23:59:59.000Z

286

Strong coupling of an optomechanical system to an anomalously dispersive atomic medium  

E-Print Network [OSTI]

We investigate a hybrid optomechanical system in which a membrane oscillator is coupled to a collective spin of ground states of an intracavity $\\Lambda$-type three-level atomic medium. The cavity field response is greatly modified by atomic coherence and the anomalous dispersion generated by two Raman pumping beams near two-photon resonance. The optomechanical interaction, therefore radiation pressure force, is substantially enhanced due to superluminal propagation of photons in the cavity. Such improvement facilitates ground-state cooling of the mechanical oscillator with room temperature thermal environment. Moreover, it can greatly improve the sensitivity and bandwidth of displacement measurement. In such system, optically-controlled strong-coupling interaction between the mechanical oscillator and cavity field could be implemented on small intracavity photon number, even at the single quanta level, which is important for weak-light nonlinear photonics and the generation of nonclassical quantum states in the mechanical field.

Haibin Wu; Min Xiao

2014-07-14T23:59:59.000Z

287

Interplay between bulk medium evolution and (D)GLV energy loss  

E-Print Network [OSTI]

We study the consistency between high-pT nuclear suppression (R_AA) and elliptic flow (v2) using Gyulassy-Levai-Vitev (GLV) energy loss or a simpler power-law dE/dL formula, for a variety of bulk evolution models. The results generally confirm our earlier work [arXiv:1305.1046] that found suppressed elliptic flow for transversely expanding media. One exception is the set of hydrodynamic solutions used recently [arXiv:1305.6458] by Betz and Gyulassy, which give significantly higher v2 but unfortunately assume unrealistic bag-model equation of state. On the other hand, we show that covariant treatment of energy loss introduces an interplay between jet direction and hydrodynamic flow of the medium, which largely counteracts elliptic flow suppression caused by transverse expansion.

Denes Molnar; Deke Sun

2014-05-19T23:59:59.000Z

288

System engineering and energy costs of small and medium wind turbines  

SciTech Connect (OSTI)

A preliminary system-level, computational model was developed to allow broad assessment and optimization of wind turbine design and costs analysis at The Wind Energy Research Center, Solar Energy Research Institute under contract to the US Department of Energy (DOE). This paper briefly describes the basic principles used in the model for energy capture and cost-of-energy (COE), and demonstrates the model's usefulness in determining the effects of rotor and system design modifications. The model's utilization for conducting parametric studies and defining the energy cost of small and medium-sized wind turbines is also shown. Topics of interest to wind turbine engineers and designers include the effects on rotor performance of airfoil geometry, blade pitch angle setting, and the system RPM schedule, etc.

Tu, P.K.C.

1985-07-01T23:59:59.000Z

289

A study of the propagation of compression waves in porous medium filled with steam  

SciTech Connect (OSTI)

A preliminary investigation on the propagation of compression waves through a radial system of porous medium filled with steam has been conducted for the case of uniform and non-uniform basic temperature distributions. When a relatively weak pressure disturbance is introduced as a signal source in a uniform temperature system, it is found that the pressure disturbance decays away and smears out as time progresses. However, for the case of a nonuniform basic temperature distribution, the temperature gradient and fluid viscosity give significant effects on the reduction of pressure signal attenuation. The attenuation of the compression waves depends on the wave frequencies. For higher frequencies the strength of the signal decays rapidly, and for lower frequencies the signal could propagate farther away. It is found also that porosity and permeability distributions gives significant effects on the amplitude and the wave profiles.

Sutrisno; Djoko Wintolo; Samsul Kamal; Sudarman, S.

1996-01-24T23:59:59.000Z

290

Kaonic atoms and in-medium K-N amplitudes II: interplay between theory and phenomenology  

E-Print Network [OSTI]

A microscopic kaonic-atom optical potential $V^{(1)}_{K^-}$ is constructed, using the Ikeda-Hyodo-Weise NLO chiral $K^-N$ subthreshold scattering amplitudes constrained by the kaonic hydrogen SIDDHARTA measurement, and incorporating Pauli correlations within the Waas-Rho-Weise generalization of the Ericson-Ericson multiple-scattering approach. Good fits to kaonic atom data over the entire periodic table require additionally sizable $K^-NN$--motivated absorptive and dispersive phenomenological terms, in agreement with our former analysis based on a post-SIDDHARTA in-medium chirally-inspired NLO separable model by Ciepl\\'{y} and Smejkal. Such terms are included by introducing a phenomenological potential $V^{(2)}_{K^-}$ and coupling it self consistently to $V^{(1)}_{K^-}$. Properties of resulting kaonic atom potentials are discussed with special attention paid to the role of $K^-$-nuclear absorption and to the extraction of density-dependent amplitudes representing $K^-$ multi-nucleon processes.

E. Friedman; A. Gal

2013-01-23T23:59:59.000Z

291

Measuring the equation of state of the high-z intergalactic medium using curvature statistics  

E-Print Network [OSTI]

Using hydrodynamical simulations, we explore the use of the mean and percentiles of the curvature distribution function to recover the equation of state of the high-$z$ ($2 < z < 4$) intergalactic medium (IGM). We find that the mean and percentiles of the absolute curvature distribution exhibit tight correlation with the temperatures measured at respective characteristic overdensities $\\bar{\\Delta}_i$'s at each redshift. Hence, they provide nearly independent probes of the same underlying temperature-density distribution, and can in principle be used to simultaneously recover both parameters $T_0$ and $\\gamma$ of the IGM effective equation of state. We quantify the associated errors in the recovered parameters $T_0$ and $\\gamma$ from the intrinsic scatter in the characteristic overdensities and the uncertainties in the curvature measurement.

Padmanabhan, Hamsa; Choudhury, T Roy

2015-01-01T23:59:59.000Z

292

Nuclear structure studies of medium-mass nuclei using large Ge arrays  

SciTech Connect (OSTI)

The advent of large Ge arrays and their ancillary detectors has greatly advanced spectroscopic studies of the medium-mass nuclei. These nuclei undergo rapid shape changes as a function of spin, excitation energy and particle number and, thus, provide a unique laboratory to test and refine a variety of theoretical models. Following a brief review of the physics motivation, some of the highlights of the experimental results obtained with the help of these powerful detector systems will be discussed. Among results presented here are the newly-discovered island of superdeformation in the A{approximately}80 mass region, and the high-spin band structures in the N{approximately}Z nuclei. These band structures may be understood in the framework of the conventional cranking models, without the introduction of additional T=0 neutron-proton pairing correlations.

Baktash, C.

1996-12-31T23:59:59.000Z

293

Dynamic synchrotron X-ray imaging study of effective temperature in a vibrated granular medium  

E-Print Network [OSTI]

We present a dynamic synchrotron X-ray imaging study of the effective temperature $T_{eff}$ in a vibrated granular medium. By tracking the directed motion and the fluctuation dynamics of the tracers inside, we obtained $T_{eff}$ of the system using Einstein relation. We found that as the system unjams with increasing vibration intensities $\\Gamma$, the structural relaxation time $\\tau$ increases substantially which can be fitted by an Arrhenius law using $T_{eff}$. And the characteristic energy scale of structural relaxation yielded by the Arrhenius fitting is $E = 0.21 \\pm 0.02$ $pd^3$, where $p$ is the pressure and $d$ is the background particle diameter, which is consistent with those from hard sphere simulations in which the structural relaxation happens via the opening up of free volume against pressure.

Yixin Cao; Xiaodan Zhang; Binquan Kou; Xiangting Li; Xianghui Xiao; Kamel Fezzaa; Yujie Wang

2014-03-21T23:59:59.000Z

294

Effective medium theory of elastic waves in random networks of rods  

E-Print Network [OSTI]

We formulate an effective medium (mean field) theory of a material consisting of randomly distributed nodes connected by straight slender rods, hinged at the nodes. Defining novel wavelength-dependent effective elastic moduli, we calculate both the static moduli and the dispersion relations of ultrasonic longitudinal and transverse elastic waves. At finite wave vector $k$ the waves are dispersive, with phase and group velocities decreasing with increasing wave vector. These results are directly applicable to networks with empty pore space. They also describe the solid matrix in two-component (Biot) theories of fluid-filled porous media. We suggest the possibility of low density materials with higher ratios of stiffness and strength to density than those of foams, aerogels or trabecular bone.

J. I. Katz; J. J. Hoffman; M. S. Conradi; J. G. Miller

2012-06-13T23:59:59.000Z

295

Acoustic Probing of the Jamming Transition in an Unconsolidated Granular Medium  

E-Print Network [OSTI]

Experiments with acoustic waves guided along the mechanically free surface of an unconsolidated granular packed structure provide information on the elasticity of granular media at very low pressures that are naturally controlled by the gravitational acceleration and the depth beneath the surface. Comparison of the determined dispersion relations for guided surface acoustic modes with a theoretical model reveals the dependencies of the elastic moduli of the granular medium on pressure. The experiments confirm recent theoretical predictions that relaxation of the disordered granular packing through non-affine motion leads to a peculiar scaling of shear rigidity with pressure near the jamming transition corresponding to zero pressure. Unexpectedly, and in disagreement with the most of the available theories, the bulk modulus depends on pressure in a very similar way to the shear modulus.

Jacob, Xavier; Tournat, Vincent; Leclaire, Philippe; Lauriks, Walter; Gusev, Vitalyi

2007-01-01T23:59:59.000Z

296

Acoustic Probing of the Jamming Transition in an Unconsolidated Granular Medium  

E-Print Network [OSTI]

Experiments with acoustic waves guided along the mechanically free surface of an unconsolidated granular packed structure provide information on the elasticity of granular media at very low pressures that are naturally controlled by the gravitational acceleration and the depth beneath the surface. Comparison of the determined dispersion relations for guided surface acoustic modes with a theoretical model reveals the dependencies of the elastic moduli of the granular medium on pressure. The experiments confirm recent theoretical predictions that relaxation of the disordered granular packing through non-affine motion leads to a peculiar scaling of shear rigidity with pressure near the jamming transition corresponding to zero pressure. Unexpectedly, and in disagreement with the most of the available theories, the bulk modulus depends on pressure in a very similar way to the shear modulus.

Xavier Jacob; Vladislav Aleshin; Vincent Tournat; Philippe Leclaire; Walter Lauriks; Vitalyi Gusev

2007-10-11T23:59:59.000Z

297

Detection of a branched alkyl molecule in the interstellar medium: iso-propyl cyanide  

E-Print Network [OSTI]

The largest non-cyclic molecules detected in the interstellar medium (ISM) are organic with a straight-chain carbon backbone. We report an interstellar detection of a branched alkyl molecule, iso-propyl cyanide (i-C3H7CN), with an abundance 0.4 times that of its straight-chain structural isomer. This detection suggests that branched carbon-chain molecules may be generally abundant in the ISM. Our astrochemical model indicates that both isomers are produced within or upon dust grain ice mantles through the addition of molecular radicals, albeit via differing reaction pathways. The production of iso-propyl cyanide appears to require the addition of a functional group to a non-terminal carbon in the chain. Its detection therefore bodes well for the presence in the ISM of amino acids, for which such side-chain structure is a key characteristic.

Belloche, Arnaud; Müller, Holger S P; Menten, Karl M

2014-01-01T23:59:59.000Z

298

Medium effects and the shear viscosity of the dilute Fermi gas away from the conformal limit  

E-Print Network [OSTI]

We study the shear viscosity of a dilute Fermi gas as a function of the scattering length in the vicinity of the unitarity limit. The calculation is based on kinetic theory, which provides a systematic approach to transport properties in the limit in which the fugacity $z=n\\lambda^3/2$ is small. Here, $n$ is the density of the gas and $\\lambda$ is the thermal wave length of the fermions. At leading order in the fugacity expansion the shear viscosity is independent of density, and the minimum shear viscosity is achieved at unitarity. At the next order medium effects modify the scattering amplitude as well as the quasi-particle energy and velocity. We show that these effects shift the minimum of the shear viscosity to the Bose-Einstein condensation (BEC) side of the resonance, in agreement with the result of recent experiments.

Marcus Bluhm; Thomas Schaefer

2014-10-10T23:59:59.000Z

299

Darcy Flow in a Wavy Channel Filled with a Porous Medium  

SciTech Connect (OSTI)

Flow in channels bounded by wavy or corrugated walls is of interest in both technological and geological contexts. This paper presents an analytical solution for the steady Darcy flow of an incompressible fluid through a homogeneous, isotropic porous medium filling a channel bounded by symmetric wavy walls. This packed channel may represent an idealized packed fracture, a situation which is of interest as a potential pathway for the leakage of carbon dioxide from a geological sequestration site. The channel walls change from parallel planes, to small amplitude sine waves, to large amplitude nonsinusoidal waves as certain parameters are increased. The direction of gravity is arbitrary. A plot of piezometric head against distance in the direction of mean flow changes from a straight line for parallel planes to a series of steeply sloping sections in the reaches of small aperture alternating with nearly constant sections in the large aperture bulges. Expressions are given for the stream function, specific discharge, piezometric head, and pressure.

Gray, Donald D.; Ogretim, Egemen; Bromhal, Grant S.

2013-07-01T23:59:59.000Z

300

An effective medium study of surface plasmon polaritons in nanostructured gratings using attenuated total reflection  

SciTech Connect (OSTI)

Recent work studied surface plasmon resonances in structured materials by the method of attenuated total reflection using a prism on top of a metallic grating. That calculation considered Transverse Magnetic polarized radiation, involved an expansion in 121 Fourier modes, and found a number of interesting features. Many of these features were attributed to localized plasmons or other factors, which arise from a discrete structure. We use a simple effective medium theory to address the same problem, and find many of the same reflection features observed in the more complex calculation, indicating that localization is not an important factor. We also evaluate the possibility of using some of the new features in the reflection spectrum for bio-sensing and find that the sensitivity of the system to small changes in relative permittivity is increased compared to some standard methods.

Tyboroski, M. H.; Anderson, N. R.; Camley, R. E. [UCCS BioFrontiers Center, University of Colorado at Colorado Springs, Colorado Springs, Colorado 80918 (United States)

2014-01-07T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Medium effects in proton-induced $K^{0}$ production at 3.5 GeV  

E-Print Network [OSTI]

We present the analysis of the inclusive $K^{0}$ production in p+p and p+Nb collisions measured with the HADES detector at a beam kinetic energy of 3.5 GeV. Data are compared to the GiBUU transport model. The data suggest the presence of a repulsive momentum-dependent kaon potential as predicted by the Chiral Perturbation Theory (ChPT). For the kaon at rest and at normal nuclear density, the ChPT potential amounts to $\\approx 35$ MeV. A detailed tuning of the kaon production cross sections implemented in the model has been carried out to reproduce the experimental data measured in p+p collisions. The uncertainties in the parameters of the model were examined with respect to the sensitivity of the experimental results from p+Nb collisions to the in-medium kaon potential.

G. Agakishiev; O. Arnold; D. Belver; A. Belyaev; J. C. Berger-Chen; A. Blanco; M. Böhmer; J. L. Boyard; P. Cabanelas; S. Chernenko; A. Dybczak; E. Epple; L. Fabbietti; O. Fateev; P. Finocchiaro; P. Fonte; J. Friese; I. Fröhlich; T. Galatyuk; J. A. Garzón; R. Gernhäuser; K. Göbel; M. Golubeva; D. González-Díaz; F. Guber; M. Gumberidze; T. Heinz; T. Hennino; R. Holzmann; A. Ierusalimov; I. Iori; A. Ivashkin; M. Jurkovic; B. Kämpfer; T. Karavicheva; I. Koenig; W. Koenig; B. W. Kolb; G. Korcyl; G. Kornakov; R. Kotte; A. Krása; F. Krizek; R. Krücken; H. Kuc; W. Kühn; A. Kugler; T. Kunz; A. Kurepin; V. Ladygin; R. Lalik; K. Lapidus; A. Lebedev; L. Lopes; M. Lorenz; L. Maier; A. Mangiarotti; J. Markert; V. Metag; J. Michel; C. Müntz; R. Münzer; L. Naumann; Y. C. Pachmayer; M. Palka; Y. Parpottas; V. Pechenov; O. Pechenova; J. Pietraszko; W. Przygoda; B. Ramstein; A. Reshetin; A. Rustamov; A. Sadovsky; P. Salabura; A. Schmah; E. Schwab; J. Siebenson; Yu. G. Sobolev; B. Spruck; H. Ströbele; J. Stroth; C. Sturm; A. Tarantola; K. Teilab; P. Tlusty; M. Traxler; H. Tsertos; T. Vasiliev; V. Wagner; M. Weber; C. Wendisch; J. Wüstenfeld; S. Yurevich; Y. Zanevsky; . T. Gaitanos; J. Weil

2014-04-29T23:59:59.000Z

302

Normal and lateral Casimir interactions between semi-infinite conductors in the presence of a dispersive medium  

SciTech Connect (OSTI)

Path-integral formalism is employed to study normal and lateral Casimir interactions in a system composed of a dispersive medium surrounded by two semi-infinite ideal conductors. The dispersive medium is modeled by a continuum of harmonic oscillators, and it is shown that for smooth conductors, the normal force at small distances in the presence of a dispersive medium coincides with the original Casimir force, while at large distances, it tends to the original form with a renormalized coefficient. The correction to the normal force because of the roughness on one of the conductors is calculated. When the inner surfaces of both conductors have roughness, the lateral Casimir interaction occurs because of translational symmetry breaking, which is studied. It is shown that both normal and lateral Casimir forces in the presence of a dispersive medium are weaker in comparison with the original one and are proportional to the roughness amplitude squared. The dependence of the normal and lateral interactions on the memory and strength of the dispersive medium is considered.

Soltani, Morteza; Sarabadani, Jalal; Kheirandish, Fardin; Rabbani, Hasan [Department of Physics, University of Isfahan, Isfahan 81746 (Iran, Islamic Republic of); Department of Physics, Faculty of Science, University of Shahrkurd, Shahrkurd 88186 (Iran, Islamic Republic of)

2010-10-15T23:59:59.000Z

303

EARLY AFTERGLOWS OF GAMMA-RAY BURSTS IN A STRATIFIED MEDIUM WITH A POWER-LAW DENSITY DISTRIBUTION  

SciTech Connect (OSTI)

A long-duration gamma-ray burst (GRB) has been widely thought to arise from the collapse of a massive star, and it has been suggested that its ambient medium is a homogenous interstellar medium (ISM) or a stellar wind. There are two shocks when an ultra-relativistic fireball that has been ejected during the prompt gamma-ray emission phase sweeps up the circumburst medium: a reverse shock that propagates into the fireball, and a forward shock that propagates into the ambient medium. In this paper, we investigate the temporal evolution of the dynamics and emission of these two shocks in an environment with a general density distribution of n?R {sup –k} (where R is the radius) by considering thick-shell and thin-shell cases. A GRB afterglow with one smooth onset peak at early times is understood to result from such external shocks. Thus, we can determine the medium density distribution by fitting the onset peak appearing in the light curve of an early optical afterglow. We apply our model to 19 GRBs and find that their k values are in the range of 0.4-1.4, with a typical value of k ? 1, implying that this environment is neither a homogenous ISM with k = 0 nor a typical stellar wind with k = 2. This shows that the progenitors of these GRBs might have undergone a new mass-loss evolution.

Yi, Shuang-Xi; Dai, Zi-Gao [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Wu, Xue-Feng, E-mail: dzg@nju.edu.cn [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

2013-10-20T23:59:59.000Z

304

Dust in the Ionized Medium of the Galaxy: GHRS Measurements of Al III and S III  

E-Print Network [OSTI]

We present interstellar absorption line measurements of the ions S III and Al III towards six stars using archival Goddard High Resolution Spectrograph data. The ions Al III and S III trace heavily depleted and non-depleted elements, respectively, in ionized gas. We use the photoionization code CLOUDY to derive the ionization correction relating N(Al III)/N(S III) to the gas-phase abundance [Al/S]_i in the ionized gas. For spectral types considered here, the corrections are small and independent of the assumed ionization parameter. Using the results of these photoionization models, we find [Al/S]_i = -1.0 in the ionized gas towards three disk stars. These values of [Al/S]_i (=[Al/H]_i) imply that Al-bearing grains are present in the ionized nebulae around these stars. If the WIM of the Galaxy is photoionized by OB stars, our data for two halo stars imply [Al/S]_i = -0.4 to -0.5 in the WIM and thus the presence of dust grains containing Al in this important phase of the ISM. While photoionization appears to be the most likely origin of the ionization for Al III and S III, we cannot rule out confusion from the presence of hot, collisionally ionized gas along two sightlines. We find that [Al/S]_i in the ionized gas along the six sightlines is anti-correlated with the electron density and average sightline neutral density. The degree of grain destruction in the ionized medium of the Galaxy is not much higher than in the warm neutral medium. The existence of grains in the ionized regions studied here has important implications for the thermal balance of these regions. (Abstract Abridged)

J. Christopher Howk; Blair D. Savage

1998-10-27T23:59:59.000Z

305

GRB 081007 AND GRB 090424: THE SURROUNDING MEDIUM, OUTFLOWS, AND SUPERNOVAE  

SciTech Connect (OSTI)

We discuss the results of the analysis of multi-wavelength data for the afterglows of GRB 081007 and GRB 090424, two bursts detected by Swift. One of them, GRB 081007, also shows a spectroscopically confirmed supernova, SN 2008hw, which resembles SN 1998bw in its absorption features, while the maximum magnitude may be fainter, up to 0.7 mag, than observed in SN 1998bw. Bright optical flashes have been detected in both events, which allows us to derive solid constraints on the circumburst-matter density profile. This is particularly interesting in the case of GRB 081007, whose afterglow is found to be propagating into a constant-density medium, yielding yet another example of a gamma-ray burst (GRB) clearly associated with a massive-star progenitor which did not sculpt the surroundings with its stellar wind. There is no supernova component detected in the afterglow of GRB 090424, likely due to the brightness of the host galaxy, comparable to the Milky Way. We show that the afterglow data are consistent with the presence of both forward- and reverse-shock emission powered by relativistic outflows expanding into the interstellar medium. The absence of optical peaks due to the forward shock strongly suggests that the reverse-shock regions should be mildly magnetized. The initial Lorentz factor of outflow of GRB 081007 is estimated to be {Gamma} {approx} 200, while for GRB 090424 a lower limit of {Gamma} > 170 is derived. We also discuss the prompt emission of GRB 081007, which consists of just a single pulse. We argue that neither the external forward-shock model nor the shock-breakout model can account for the prompt emission data and suggest that the single-pulse-like prompt emission may be due to magnetic energy dissipation of a Poynting-flux-dominated outflow or to a dissipative photosphere.

Jin Zhiping; Covino, Stefano; Fugazza, Dino; Melandri, Andrea; Campana, Sergio; D'Avanzo, Paolo [INAF-Osservatorio Astronomico di Brera, via Emilio Bianchi 46, I-23807 Merate (Italy); Della Valle, Massimo [INAF-Osservatorio Astronomico di Capodimonte, Salita Moiariello, 16, I-80131 Napoli (Italy); Ferrero, Patrizia [Instituto de Astrofisica de Canarias (IAC), E-38200 La Laguna, Tenerife (Spain); Malesani, Daniele; Fynbo, Johan P. U.; Hjorth, Jens [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen O (Denmark); Pian, Elena [Scuola Normale Superiore di Pisa, Piazza dei Cavalieri 7, I-56126 Pisa (Italy); Salvaterra, Ruben [INAF-IASF Milano, via E. Bassini 15, I-20133 Milano (Italy); Bersier, David [Astrophysics Research Institute, Liverpool John Moores University, Egerton Wharf, Birkenhead CH41 1LD (United Kingdom); Cano, Zach [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Reykjavik (Iceland); Castro-Tirado, Alberto J.; Gorosabel, Javier [Instituto de Astrofisica de Andalucia (IAA-CSIC), Glorieta de la Astronomia s/n, E-18008 Granada (Spain); Gomboc, Andreja [Mathematics and Physics, University of Ljubljana, Jadranska ulica 19, 1000 Ljubljana (Slovenia); Guidorzi, Cristiano [Department of Physics, University of Ferrara, via Saragat 1, I-44122 Ferrara (Italy); Haislip, Joshua B., E-mail: jin@pmo.ac.cn [Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599 (United States); and others

2013-09-10T23:59:59.000Z

306

PROPAGATION OF SEISMIC WAVES THROUGH A SPATIO-TEMPORALLY FLUCTUATING MEDIUM: HOMOGENIZATION  

SciTech Connect (OSTI)

Measurements of seismic wave travel times at the photosphere of the Sun have enabled inferences of its interior structure and dynamics. In interpreting these measurements, the simplifying assumption that waves propagate through a temporally stationary medium is almost universally invoked. However, the Sun is in a constant state of evolution, on a broad range of spatio-temporal scales. At the zero-wavelength limit, i.e., when the wavelength is much shorter than the scale over which the medium varies, the WKBJ (ray) approximation may be applied. Here, we address the other asymptotic end of the spectrum, the infinite-wavelength limit, using the technique of homogenization. We apply homogenization to scenarios where waves are propagating through rapidly varying media (spatially and temporally), and derive effective models for the media. One consequence is that a scalar sound speed becomes a tensorial wave speed in the effective model and anisotropies can be induced depending on the nature of the perturbation. The second term in this asymptotic two-scale expansion, the so-called corrector, contains contributions due to higher-order scattering, leading to the decoherence of the wave field. This decoherence may be causally linked to the observed wave attenuation in the Sun. Although the examples we consider here consist of periodic arrays of perturbations to the background, homogenization may be extended to ergodic and stationary random media. This method may have broad implications for the manner in which we interpret seismic measurements in the Sun and for modeling the effects of granulation on the scattering of waves and distortion of normal-mode eigenfunctions.

Hanasoge, Shravan M. [Department of Geosciences, Princeton University, Princeton, NJ 08544 (United States); Gizon, Laurent [Max-Planck-Institut fuer Sonnensystemforschung, D-37191 Katlenburg-Lindau (Germany); Bal, Guillaume [Department of Applied and Physical Mathematics, Columbia University, New York, NY 10027 (United States)

2013-08-20T23:59:59.000Z

307

Medium Truck Duty Cycle Data from Real-World Driving Environments: Final Report  

SciTech Connect (OSTI)

Since the early part of the 20th century, the US trucking industry has provided a safe and economical means of moving commodities across the country. At present, nearly 80% of US domestic freight movement involves the use of trucks. The US Department of Energy (DOE) is spearheading a number of research efforts to improve heavy vehicle fuel efficiencies. This includes research in engine technologies (including hybrid and fuel cell technologies), lightweight materials, advanced fuels, and parasitic loss reductions. In addition, DOE is developing advanced tools and models to support heavy vehicle research and is leading the 21st Century Truck Partnership and the SuperTruck development effort. Both of these efforts have the common goal of decreasing the fuel consumption of heavy vehicles. In the case of SuperTruck, a goal of improving the overall freight efficiency of a combination tractor-trailer has been established. This Medium Truck Duty Cycle (MTDC) project is a critical element in DOE s vision for improved heavy vehicle energy efficiency; it is unique in that there is no other existing national database of characteristic duty cycles for medium trucks based on collecting data from Class 6 and 7 vehicles. It involves the collection of real-world data on medium trucks for various situational characteristics (e.g., rural/urban, freeway/arterial, congested/free-flowing, good/bad weather) and looks at the unique nature of medium trucks drive cycles (stop-and-go delivery, power takeoff, idle time, short-radius trips). This research provides a rich source of data that can contribute to the development of new tools for FE and modeling, provide DOE a sound basis upon which to make technology investment decisions, and provide a national archive of real-world-based medium-truck operational data to support energy efficiency research. The MTDC project involved a two-part field operational test (FOT). For the Part-1 FOT, three vehicles each from two vocations (urban transit and dry-box delivery) were instrumented for the collection of one year of operational data. The Part-2 FOT involved the towing and recovery and utility vocations for a second year of data collection. The vehicles that participated in the MTDC project did so through gratis partnerships in return for early access to the results of this study. Partnerships such as these are critical to FOTs in which real-world data is being collected. In Part 1 of the project, Oak Ridge National Laboratory (ORNL) established partnerships with the H.T. Hackney Company (HTH), one of the largest wholesale distributors in the country, distributing products to 21 states; and with Knoxville Area Transit (KAT), the city of Knoxville s transit system, which operates across Knoxville and parts of Knox County. These partnerships and agreements provided ORNL access to three Class-7 day-cab tractors that regularly haul 28 ft pup trailers (HTH) and three Class-7 buses for the collection of duty cycle data. In addition, ORNL collaborated with the Federal Motor Carrier Safety Administration (FMCSA) to determine if there were possible synergies between this duty cycle data collection effort and FMCSA s need to learn more about the operation and duty cycles of medium trucks. FMCSA s primary interest was in collecting safety data relative to the driver, carrier, and vehicle. In Part 2 of the project, ORNL partnered with the Knoxville Utilities Board, which made available three Class-8 trucks. Fountain City Wrecker Service was also a Part 2 partner, providing three Class-6 rollback trucks. In order to collect the duty cycle and safety-related data, ORNL developed a data acquisition system (DAS) that was placed on each test vehicle. Each signal recorded in this FOT was collected by means of one of the instruments incorporated into each DAS. Other signals were obtained directly from the vehicle s J1939 and J1708 data buses. A VBOX II Lite collected information available from a global positioning system (GPS), including speed, acceleration, and spatial location information at a rate of 5 Hz for the Part 1

Lascurain, Mary Beth [ORNL; Franzese, Oscar [ORNL; Capps, Gary J [ORNL; Siekmann, Adam [ORNL; Thomas, Neil [ORNL; LaClair, Tim J [ORNL; Barker, Alan M [ORNL; Knee, Helmut E [ORNL

2012-11-01T23:59:59.000Z

308

Aggravation of Pre-Existing Atrioventricular Block, Wenckebach Type, Provoked by Application of X-Ray Contrast Medium  

SciTech Connect (OSTI)

Background. Significant bradycardia followed by cardiac arrest related to single bolus administration of X-ray contrast medium into a peripheral artery has not, to our knowledge, been described in the literature. Methods and Results. While performing a percutaneous transluminal angioplasty of the left superficial femoral artery in a 68-year old patient with a pre-existing atrioventricular (AV) block, Wenckebach type, he developed an AV block III after a single bolus injection of intra-arterial X-ray contrast medium. Conclusion. We believe that application of contrast medium causes a transitory ischemia in the obstructed vessel and therefore elevation of endogenous adenosine. In the case of a previously damaged AV node this elevation of endogenous adenosine may be responsible for the development of a short period of third-degree AV block.

Brodmann, Marianne, E-mail: marianne.brodmann@meduni-graz.at; Seinost, Gerald [Medizinische Universitaet Graz, Division of Angiology, Department of Internal Medicine (Austria); Stark, Gerhard [LKH Deutschlandsberg, Department of Internal Medicine (Austria); Pilger, Ernst [Medizinische Universitaet Graz, Division of Angiology, Department of Internal Medicine (Austria)

2006-12-15T23:59:59.000Z

309

Analytical optimization of digital subtraction mammography with contrast medium using a commercial unit  

SciTech Connect (OSTI)

Contrast-medium-enhanced digital mammography (CEDM) is an image subtraction technique which might help unmasking lesions embedded in very dense breasts. Previous works have stated the feasibility of CEDM and the imperative need of radiological optimization. This work presents an extension of a former analytical formalism to predict contrast-to-noise ratio (CNR) in subtracted mammograms. The goal is to optimize radiological parameters available in a clinical mammographic unit (x-ray tube anode/filter combination, voltage, and loading) by maximizing CNR and minimizing total mean glandular dose (D{sub gT}), simulating the experimental application of an iodine-based contrast medium and the image subtraction under dual-energy nontemporal, and single- or dual-energy temporal modalities. Total breast-entrance air kerma is limited to a fixed 8.76 mGy (1 R, similar to screening studies). Mathematical expressions obtained from the formalism are evaluated using computed mammographic x-ray spectra attenuated by an adipose/glandular breast containing an elongated structure filled with an iodinated solution in various concentrations. A systematic study of contrast, its associated variance, and CNR for different spectral combinations is performed, concluding in the proposal of optimum x-ray spectra. The linearity between contrast in subtracted images and iodine mass thickness is proven, including the determination of iodine visualization limits based on Rose's detection criterion. Finally, total breast-entrance air kerma is distributed between both images in various proportions in order to maximize the figure of merit CNR{sup 2}/D{sub gT}. Predicted results indicate the advantage of temporal subtraction (either single- or dual-energy modalities) with optimum parameters corresponding to high-voltage, strongly hardened Rh/Rh spectra. For temporal techniques, CNR was found to depend mostly on the energy of the iodinated image, and thus reduction in D{sub gT} could be achieved if the spectral energy of the noniodinated image is decreased and the breast-entrance air kerma is evenly distributed between both acquisitions. Predicted limits, in terms of iodine concentration, are found to guarantee the visualization of common clinical angiogenic concentrations in the breast.

Rosado-Mendez, I.; Palma, B. A.; Brandan, M. E. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, 04510 Mexico City (Mexico)

2008-12-15T23:59:59.000Z

310

VERTICAL STRUCTURE OF A SUPERNOVA-DRIVEN TURBULENT, MAGNETIZED INTERSTELLAR MEDIUM  

SciTech Connect (OSTI)

Stellar feedback drives the circulation of matter from the disk to the halo of galaxies. We perform three-dimensional magnetohydrodynamic simulations of a vertical column of the interstellar medium with initial conditions typical of the solar circle in which supernovae drive turbulence and determine the vertical stratification of the medium. The simulations were run using a stable, positivity-preserving scheme for ideal MHD implemented in the FLASH code. We find that the majority ( Almost-Equal-To 90%) of the mass is contained in thermally stable temperature regimes of cold molecular and atomic gas at T < 200 K or warm atomic and ionized gas at 5000 K < T < 10{sup 4.2} K, with strong peaks in probability distribution functions of temperature in both the cold and warm regimes. The 200-10{sup 4.2} K gas fills 50%-60% of the volume near the plane, with hotter gas associated with supernova remnants (30%-40%) and cold clouds (<10%) embedded within. At |z| {approx} 1-2 kpc, transition-temperature (10{sup 5} K) gas accounts for most of the mass and volume, while hot gas dominates at |z| > 3 kpc. The magnetic field in our models has no significant impact on the scale heights of gas in each temperature regime; the magnetic tension force is approximately equal to and opposite the magnetic pressure, so the addition of the field does not significantly affect the vertical support of the gas. The addition of a magnetic field does reduce the fraction of gas in the cold (<200 K) regime with a corresponding increase in the fraction of warm ({approx}10{sup 4} K) gas. However, our models lack rotational shear and thus have no large-scale dynamo, which reduces the role of the field in the models compared to reality. The supernovae drive oscillations in the vertical distribution of halo gas, with the period of the oscillations ranging from Almost-Equal-To 30 Myr in the T < 200 K gas to {approx}100 Myr in the 10{sup 6} K gas, in line with predictions by Walters and Cox.

Hill, Alex S.; Matthew Haffner, L. [Department of Astronomy, University of Wisconsin-Madison, Madison, WI (United States); Ryan Joung, M. [Department of Astronomy, Columbia University, New York, NY (United States); Mac Low, Mordecai-Mark [Department of Astrophysics, American Museum of Natural History, New York, NY (United States); Benjamin, Robert A. [Department of Physics, University of Wisconsin-Whitewater, Whitewater, WI (United States); Klingenberg, Christian [Department of Mathematics, Wuerzburg University, Emil Fischer Strasse 30, Wuerzburg (Germany); Waagan, Knut, E-mail: alex.hill@csiro.au [Department of Applied Mathematics, University of Washington, Seattle, WA (United States)

2012-05-10T23:59:59.000Z

311

Proposal for the Purchase, Without a Call for Tenders, of a Medium-Temperature Hot Water Boiler for the 300 GeV Accelerator  

E-Print Network [OSTI]

Proposal for the Purchase, Without a Call for Tenders, of a Medium-Temperature Hot Water Boiler for the 300 GeV Accelerator

1976-01-01T23:59:59.000Z

312

Method for compressing and heating a heating medium to be externally supplied to an engine while using the energy available in the hot exhaust gases of the engine  

SciTech Connect (OSTI)

In a method for compressing and heating a heating medium to be externally supplied to an engine, while using the energy available in the hot exhaust gases of the engine, the exhaust gases are caused to expand in at least two expansion stages to emit energy for compressing the heating medium in at least two compression stages, heat is transmitted from the exhaust gases after the first expansion stage to the heating medium after the last compression stage, and the heating medium is thereafter supplied with additional heat in a heat-producing unit before it is led to the engine.

Carlquist, S. G.

1985-06-04T23:59:59.000Z

313

Electromagnetic wave propagation in an active medium and the equivalent Schrdinger equation with an energy-dependent complex potential  

E-Print Network [OSTI]

Electromagnetic wave propagation in an active medium and the equivalent Schrödinger equation with an energy-dependent complex potential H. Bahlouli,* A. D. Alhaidari, and A. Al Zahrani Physics Department to provide an alternative, but equivalent, representation of plane electromagnetic em wave propagation

314

Abstract Pitting corrosion of aluminum 2024 in Luria Bertani medium was reduced by the secretion of anionic  

E-Print Network [OSTI]

Abstract Pitting corrosion of aluminum 2024 in Luria Bertani medium was reduced by the secretion Bacillus subtilis WB600/pBE92- Asp biofilm slightly reduced the corrosion rate of the pas- sive aluminum the corrosion rate by 90% (compared to the B. sub- tilis WB600/pBE92 biofilm which did not secrete polyas

Wood, Thomas K.

315

PON-10-603 Advanced Medium-and Heavy-Duty Vehicle Technologies Pre-Commercial Demonstrations Questions and Answers  

E-Print Network [OSTI]

-for-profit technology entities might include, but are not limited to: CalETC CALSTART California Biodiesel AlliancePON-10-603 Advanced Medium- and Heavy-Duty Vehicle Technologies Pre-Commercial Demonstrations-for-profit technology entity who will be responsible for administering the block grant and coordinating projects

316

The Changing State of British Enterprise Growth, Innovation and Competitive Advantage in Small and Medium Sized Firms 1986-95  

E-Print Network [OSTI]

1,000 small and medium sized enterprises (SMEs) in the manufacturing and business service sectors special emphasis upon the innovative activity of SMEs. This report therefore provides the most detailed technology transfer occurs in the SME sector, This is set against the background of a detailed examination

de Gispert, Adrià

317

April 15, 2004 / Vol. 29, No. 8 / OPTICS LETTERS 887 Optical light bullets in a pure Kerr medium  

E-Print Network [OSTI]

April 15, 2004 / Vol. 29, No. 8 / OPTICS LETTERS 887 Optical light bullets in a pure Kerr medium 1 1 D optical bullets. Similarly to solitons, these bullets undergo elastic collisions. Since may be used to realize experimentally stable, nondissipative optical bullets. © 2004 Optical Society

Fibich, Gadi

318

International Energy Conference, 19 -21 May 2003 Energy Technologies for post-Kyoto targets in the medium term  

E-Print Network [OSTI]

Aquifers and Hydrocarbon Structures Power & Heat Air Air O2 N2 & O2 CO2 CO2 CO2 Compression & DehydrationInternational Energy Conference, 19 - 21 May 2003 Energy Technologies for post-Kyoto targets in the medium term CO2 Capture & Geological Storage Niels Peter Christensen International Ventures Director

319

Treatment of methyl t-butyl ether contaminated water using a dense medium plasma reactor, a mechanistic and kinetic investigation  

E-Print Network [OSTI]

and oxidation mechanisms of methyl t-butyl ether (MTBE) in a dense medium plasma (DMP) reactor utilizing gas for the removal of MTBE from an aqueous solution in the DMP reactor. Rate constants are also derived for three reactor configurations and two pin array spin rates. The oxidation products from the treatment of MTBE

Dandy, David

320

Quantification of Liquid Water Saturation in a PEM Fuel Cell Diffusion Medium Using X-ray Microtomography  

E-Print Network [OSTI]

Quantification of Liquid Water Saturation in a PEM Fuel Cell Diffusion Medium Using X understanding of the two-phase flow and flooding occurrence in proton exchange membrane PEM fuel cells. We have as ice formation during cold start of PEM fuel cells. The water present in these porous layers

Note: This page contains sample records for the topic "medium medium medium" 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

Miscible droplets in a porous medium and the effects of Korteweg Ching-Yao Chen and Lilin Wang  

E-Print Network [OSTI]

the growth of the viscous fingering instability, while simultaneously generating larger stabilizing Korteweg as technological situa- tions ranging from groundwater contamination and enhanced oil recovery to biomedicalARTICLES Miscible droplets in a porous medium and the effects of Korteweg stresses Ching-Yao Chen

Meiburg, Eckart H.

322

PHYSICAL REVIEW C 87, 054616 (2013) Microscopic in-medium nucleon-nucleon cross sections with improved Pauli blocking effects  

E-Print Network [OSTI]

for nuclear reactions at intermediate energies (20 Elab 300 MeV/nucleon) and for nuclear structure in general the role of optical potentials commonly used in low energy reactions [8]. Examples such as knockout been typically employed to describe intermediate-energy HI reactions. In-medium two-body cross sections

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

323

To be submitted to Concrete Science and Engineering (August, 1999) New e ective medium theory for the di usivity or  

E-Print Network [OSTI]

To be submitted to Concrete Science and Engineering (August, 1999) New e#11;ective medium theory for the di#11;usivity or conductivity of a multi-scale concrete microstructure model E.J. Garboczi National, CA 94551-9900 Abstract To attempt to represent concrete properly as a composite material, one must

324

Atmospheric Circulation and Its Effect on Arctic Sea Ice in CCSM3 Simulations at Medium and High Resolution*  

E-Print Network [OSTI]

the Canadian archipelago, where the T85 winds produce thicker ice than their T42 counterparts. Seasonal forcingAtmospheric Circulation and Its Effect on Arctic Sea Ice in CCSM3 Simulations at Medium and High) ABSTRACT The simulation of Arctic sea ice and surface winds changes significantly when Community Climate

Bitz, Cecilia

325

Lead-iron phosphate glass as a containment medium for the disposal of high-level nuclear wastes  

DOE Patents [OSTI]

Disclosed are lead-iron phosphate glasses containing a high level of Fe/sub 2/O/sub 3/ for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste

Boatner, L.A.; Sales, B.C.

1984-04-11T23:59:59.000Z

326

Benchmark Evaluation of the Medium-Power Reactor Experiment Program Critical Configurations  

SciTech Connect (OSTI)

A series of small, compact critical assembly (SCCA) experiments were performed in 1962-1965 at the Oak Ridge National Laboratory Critical Experiments Facility (ORCEF) for the Medium-Power Reactor Experiment (MPRE) program. The MPRE was a stainless-steel clad, highly enriched uranium (HEU)-O2 fuelled, BeO reflected reactor design to provide electrical power to space vehicles. Cooling and heat transfer were to be achieved by boiling potassium in the reactor core and passing vapor directly through a turbine. Graphite- and beryllium-reflected assemblies were constructed at ORCEF to verify the critical mass, power distribution, and other reactor physics measurements needed to validate reactor calculations and reactor physics methods. The experimental series was broken into three parts, with the third portion of the experiments representing the beryllium-reflected measurements. The latter experiments are of interest for validating current reactor design efforts for a fission surface power reactor. The entire series has been evaluated as acceptable benchmark experiments and submitted for publication in the International Handbook of Evaluated Criticality Safety Benchmark Experiments and in the International Handbook of Evaluated Reactor Physics Benchmark Experiments.

Margaret A. Marshall; John D. Bess

2013-02-01T23:59:59.000Z

327

The Enrichment of Intergalactic Medium With Adiabatic Feedback I: Metal Cooling and Metal Diffusion  

E-Print Network [OSTI]

A study of IGM metal enrichment using a series of SPH simulations is presented, employing metal cooling and the turbulent diffusion of metals and thermal energy. Stellar feedback naturally drives winds in the simulations reproducing both the observed star formation history (SFH) and the universal neutral hydrogen fraction. This challenges assumptions that wind recipes are necessary for correct SFH. The mass and metal evolution in stars and various gas phases was investigated. At z=0, 40 % of the baryons are in the warm-hot intergalactic medium (WHIM), but most metals (82 %) are in stars. At higher z the most metals were in the IGM was higher due to more efficient winds. This indicates that IGM metals primarily reside in the WHIM throughout cosmic history (unlike momentum driven wind model). The WHIM metallicity is 0.01-0.1 solar with a slight decrease at lower z. The metallicity evolution is consistent with observations. Galactic winds most efficiently enrich the IGM for intermediate mass galaxies ($10^{10}$M...

Shen, Sijing; Stinson, Gregory

2009-01-01T23:59:59.000Z

328

Low energy consumption method for separating gaseous mixtures and in particular for medium purity oxygen production  

DOE Patents [OSTI]

A method for the separation of gaseous mixtures such as air and for producing medium purity oxygen, comprising compressing the gaseous mixture in a first compressor to about 3.9-4.1 atmospheres pressure, passing said compressed gaseous mixture in heat exchange relationship with sub-ambient temperature gaseous nitrogen, dividing the cooled, pressurized gaseous mixture into first and second streams, introducing the first stream into the high pressure chamber of a double rectification column, separating the gaseous mixture in the rectification column into a liquid oxygen-enriched stream and a gaseous nitrogen stream and supplying the gaseous nitrogen stream for cooling the compressed gaseous mixture, removing the liquid oxygen-enriched stream from the low pressure chamber of the rectification column and pumping the liquid, oxygen-enriched steam to a predetermined pressure, cooling the second stream, condensing the cooled second stream and evaporating the oxygen-enriched stream in an evaporator-condenser, delivering the condensed second stream to the high pressure chamber of the rectification column, and heating the oxygen-enriched stream and blending the oxygen-enriched stream with a compressed blend-air stream to the desired oxygen concentration.

Jujasz, Albert J. (North Olmsted, OH); Burkhart, James A. (Olmsted Falls, OH); Greenberg, Ralph (New York, NY)

1988-01-01T23:59:59.000Z

329

Progress in the Development of Global Medium-Energy Nucleon-Nucleus Optical Model Potentials  

E-Print Network [OSTI]

Two existing global medium-energy nucleon-nucleus phenomenological optical model potentials are described and compared with experiment and with each other. The first of these employs a Dirac approach (second-order reduction) that is global in projectile energy and projectile isospin and applies to the target nucleus 208-Pb. Here the standard S-V (isoscalar-scalar, isoscalar-vector) model has been extended to include the corresponding isovector components by introduction of a relativistic Lane model. The second of these employs a relativistic equivalent to the Schroedinger equation and is global in projectile energy, projectile isospin, and target (Z,A). Here, particular attention is given to predictions for the integrated scattering observables - neutron total cross sections and proton total reaction cross sections - and their sensitivity to the absorptive parts of the potential. Finally, current work is described and the influence of the nuclear bound state problem (treated in relativistic mean field theory) on the Dirac scattering problem is mentioned.

David G. Madland

1997-02-14T23:59:59.000Z

330

Interactions of a Light Hypersonic Jet with a Non-Uniform Interstellar Medium  

E-Print Network [OSTI]

We present three dimensional simulations of the interaction of a light hypersonic jet with an inhomogeneous thermal and turbulently supported disk in an elliptical galaxy. We model the jet as a light, supersonic non-relativistic flow with parameters selected to be consistent with a relativistic jet with kinetic power just above the FR1/FR2 break. We identify four generic phases in the evolution of such a jet with the inhomogeneous interstellar medium: 1) an initial ``flood and channel'' phase, where progress is characterized by high pressure gas finding changing weak points in the ISM, flowing through channels that form and re-form over time, 2) a spherical, energy-driven bubble phase, were the bubble is larger than the disk scale, but the jet remains fully disrupted close to the nucleus, 3) a rapid, jet break--out phase the where jet breaks free of the last dense clouds, becomes collimated and pierces the spherical bubble, and 4) a classical phase, the jet propagates in a momentum-dominated fashion leading to the classical jet + cocoon + bow-shock structure. Mass transport in the simulations is investigated, and we propose a model for the morphology and component proper motions in the well-studied Compact Symmetric Object 4C31.04.

R. S. Sutherland; G. V. Bicknell

2007-07-25T23:59:59.000Z

331

Astrophysical bow shocks: An analytical solution for the hypersonic blunt body problem in the intergalactic medium  

E-Print Network [OSTI]

Aims: Bow shock waves are a common feature of groups and clusters of galaxies since they are generated as a result of supersonic motion of galaxies through the intergalactic medium. The goal of this work is to present an analytical solution technique for such astrophysical hypersonic blunt body problems. Methods: A method, developed by Schneider (1968, JFM, 31, 397) in the context of aeronautics, allows calculation of the galaxy's shape as long as the shape of the bow shock wave is known (so-called inverse method). In contrast to other analytical models, the solution is valid in the whole flow region (from the stagnation point up to the bow shock wings) and in particular takes into account velocity gradients along the streamlines. We compare our analytical results with two-dimensional hydrodynamical simulations carried out with an extended version of the VH-1 hydrocode which is based on the piecewise parabolic method with a Lagrangian remap. Results: It is shown that the applied method accurately predicts the...

Schulreich, Michael Mathias

2011-01-01T23:59:59.000Z

332

Interactions of a Light Hypersonic Jet with a Non-Uniform Interstellar Medium  

E-Print Network [OSTI]

We present three dimensional simulations of the interaction of a light hypersonic jet with an inhomogeneous thermal and turbulently supported disk in an elliptical galaxy. We model the jet as a light, supersonic non-relativistic flow with parameters selected to be consistent with a relativistic jet with kinetic power just above the FR1/FR2 break. We identify four generic phases in the evolution of such a jet with the inhomogeneous interstellar medium: 1) an initial ``flood and channel'' phase, where progress is characterized by high pressure gas finding changing weak points in the ISM, flowing through channels that form and re-form over time, 2) a spherical, energy-driven bubble phase, were the bubble is larger than the disk scale, but the jet remains fully disrupted close to the nucleus, 3) a rapid, jet break--out phase the where jet breaks free of the last dense clouds, becomes collimated and pierces the spherical bubble, and 4) a classical phase, the jet propagates in a momentum-dominated fashion leading t...

Sutherland, R S

2007-01-01T23:59:59.000Z

333

Laser utilizing a gaseous lasing medium and method for operating the same  

DOE Patents [OSTI]

The invention relates to an improvement in gas lasers and a method of operating the same. In one aspect, the invention is an improved method for operating a high-power gas laser. The improvement comprises introducing the gas lasing medium tangentially to the laser tube at a pressure establishing a forced vortex in the tube. The vortex defines an axially extending core region characterized by a low pressure and temperature relative to the gas inlet and the exterior of the vortex. An electrical discharge is established in the core region to initiate lasing of the gas. The gas discharge from the tube is passed through a diffuser. As in conventional gas lasers, firing results in a very abrupt increase in gas temperature and in severe disruption of the gas. However, the gas vortex almost immediately restores the gas to its pre-firing condition. That is, almost all of the waste heat is transferred radially to the laser wall, and the original gas-flow pattern is restored. As a result, the power output of the laser is increased significantly, and the laser firing repetition rate is markedly increased.

Zerr, Bruce A. (Harriman, TN)

1986-01-01T23:59:59.000Z

334

Model-Based Analysis of Electric Drive Options for Medium-Duty Parcel Delivery Vehicles: Preprint  

SciTech Connect (OSTI)

Medium-duty vehicles are used in a broad array of fleet applications, including parcel delivery. These vehicles are excellent candidates for electric drive applications due to their transient-intensive duty cycles, operation in densely populated areas, and relatively high fuel consumption and emissions. The National Renewable Energy Laboratory (NREL) conducted a robust assessment of parcel delivery routes and completed a model-based techno-economic analysis of hybrid electric vehicle (HEV) and plug-in hybrid electric vehicle configurations. First, NREL characterized parcel delivery vehicle usage patterns, most notably daily distance driven and drive cycle intensity. Second, drive-cycle analysis results framed the selection of drive cycles used to test a parcel delivery HEV on a chassis dynamometer. Next, measured fuel consumption results were used to validate simulated fuel consumption values derived from a dynamic model of the parcel delivery vehicle. Finally, NREL swept a matrix of 120 component size, usage, and cost combinations to assess impacts on fuel consumption and vehicle cost. The results illustrated the dependency of component sizing on drive-cycle intensity and daily distance driven and may allow parcel delivery fleets to match the most appropriate electric drive vehicle to their fleet usage profile.

Barnitt, R. A.; Brooker, A. D.; Ramroth, L.

2010-12-01T23:59:59.000Z

335

A medium-energy photoemission and ab-initio investigation of cubic yttria-stabilised zirconia  

SciTech Connect (OSTI)

Experimental and theoretical investigations into the electronic properties and structure of cubic yttria-stabilized zirconia are presented. Medium-energy x-ray photoemission spectroscopy measurements have been carried out for material with a concentration of 8-9?mol.?% yttria. Resonant photoemission spectra are obtained for a range of photon energies that traverse the L2 absorption edge for both zirconium and yttrium. Through correlation with results from density-functional theory (DFT) calculations, based on structural models proposed in the literature, we assign photoemission peaks appearing in the spectra to core lines and Auger transitions. An analysis of the core level features enables the identification of shifts in the core level energies due to different local chemical environments of the constituent atoms. In general, each core line feature can be decomposed into three contributions, with associated energy shifts. Their identification with results of DFT calculations carried out for proposed atomic structures, lends support to these structural models. The experimental results indicate a multi-atom resonant photoemission effect between nearest-neighbour oxygen and yttrium atoms. Near-edge x-ray absorption fine structure spectra for zirconium and yttrium are also presented, which correlate well with calculated Zr- and Y-4d electron partial density-of-states and with Auger electron peak area versus photon energy curve.

Cousland, G. P. [School of Physics, The University of Sydney, New South Wales 2006 (Australia); Australian Nuclear Science and Technology Organisation, Lucas Heights, New South Wales 2234 (Australia); Cui, X. Y. [School of Physics, The University of Sydney, New South Wales 2006 (Australia); Australian Centre for Microscopy and Microanalysis, The University of Sydney, New South Wales 2006 (Australia); Smith, A. E. [School of Physics, Monash University, Clayton, Victoria 3800 (Australia); Stampfl, C. M. [School of Physics, The University of Sydney, New South Wales 2006 (Australia); School of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Wong, L.; Tayebjee, M.; Yu, D.; Triani, G.; Evans, P. J. [Australian Nuclear Science and Technology Organisation, Lucas Heights, New South Wales 2234 (Australia); Ruppender, H.-J. [OmniVac GmbH, Espensteigstrasse 16, 67661 Kaiserslautern (Germany); Jang, L.-Y. [National Synchrotron Radiation Research Center, Hsinchu Science Park, Hsinchu 30076, Taiwan (China); Stampfl, A. P. J. [Australian Nuclear Science and Technology Organisation, Lucas Heights, New South Wales 2234 (Australia); School of Chemistry, The University of Sydney, New South Wales 2006 (Australia)

2014-04-14T23:59:59.000Z

336

The effect of grain size distribution on H$_2$ formation rate in the interstellar medium  

E-Print Network [OSTI]

The formation of molecular hydrogen in the interstellar medium takes place on the surfaces of dust grains. Hydrogen molecules play a role in gas-phase reactions that produce other molecules, some of which serve as coolants during gravitational collapse and star formation. Thus, the evaluation of the roduction rate of hydrogen molecules and its dependence on the physical conditions in the cloud are of great importance. Interstellar dust grains exhibit a broad size distribution in which the small grains capture most of the surface area. Recent studies have shown that the production efficiency strongly depends on the grain composition and temperature as well as on its size. In this paper we present a formula which provides the total production rate of H$_2$ per unit volume in the cloud, taking into account the grain composition and temperature as well as the grain size distribution. The formula agrees very well with the master equation results. It shows that for a physically relevant range of grain temperatures, the production rate of H$_2$ is significantly enhanced due to their broad size distribution.

Azi Lipshtat; Ofer Biham

2005-08-01T23:59:59.000Z

337

Tracing the distribution and evolution of Iron in the IntraCluster Medium  

E-Print Network [OSTI]

Emission lines in X-ray spectra of clusters of galaxies reveal the presence of heavy elements in the diffuse hot plasma (ICM) in virial equilibrium in the dark matter potential well. Thanks to the X-ray satellites Chandra and XMM-Newton we are now able to measure with good accuracy the distribution and evolution of Iron up to redshift z ~ 1.3. The capability of studying the chemical and thermodynamical properties of the ICM in high redshift clusters is an efficient tool to constrain the interaction processes between the cluster galaxies and the surrounding medium. We confirm that the ICM is already significantly enriched at a look-back time of 9 Gyr, and find that the Iron abundance change with redshift as (1+z)^(-1.25), implying an increase of a factor of ~2 with respect to z=1.3. This result can be explained by a prompt enrichment by star formation processes in massive ellipticals at z>2, followed by a slower release of enriched gas from disk galaxies into the ICM, associated to a morphological transition from disk to S0.

P. Tozzi

2008-01-24T23:59:59.000Z

338

Observations of the Intergalactic Medium and the Cosmic Web in the SKA era  

E-Print Network [OSTI]

The interaction of galaxies with their environment, the Intergalactic Medium (IGM), is an important aspect of galaxy formation. One of the most fundamental, but unanswered questions in the evolution of galaxies is how gas circulates in and around galaxies and how it enters the galaxies to support star formation. We have several lines of evidence that the observed evolution of star formation requires gas accretion from the IGM at all times and on all cosmic scales. This gas remains largely unaccounted for and the outstanding questions are where this gas resides and what the physical mechanisms of accretion are. The gas is expected to be embedded in an extended cosmic web made of sheets and filaments. Such large-scale filaments of gas are expected by cosmological numerical simulations, which have made significant progress in recent years. Such simulations do not only model the large scale structure of the cosmic web, but also investigate the neutral gas component. To truly make significant progress in understan...

Popping, A; Staveley-Smith, L; Obreschkow, D; Jozsa, G I; Pisano, D J

2015-01-01T23:59:59.000Z

339

A dynamical model of supernova feedback: gas outflows from the interstellar medium  

E-Print Network [OSTI]

We present a dynamical model of supernova feedback which follows the evolution of pressurised bubbles driven by supernovae in a multi-phase interstellar medium (ISM). The bubbles are followed until the point of break-out into the halo, starting from an initial adiabatic phase to a radiative phase. We show that a key property which sets the fate of bubbles in the ISM is the gas surface density, through the work done by the expansion of bubbles and its role in setting the gas scaleheight. The multi-phase description of the ISM is essential, and neglecting it leads to order of magnitude differences in the predicted outflow rates. We compare our predicted mass loading and outflow velocities to observations of local and high-redshift galaxies and find good agreement. With the aim of analysing the dependence of the mass loading of the outflow, $\\beta$ (i.e. the ratio between the outflow and star formation rates), on galaxy properties, we embed our model in the galaxy formation simulation, GALFORM, set in the $\\Lamb...

Lagos, Claudia; Baugh, C M

2013-01-01T23:59:59.000Z

340

Development of high productivity medium current ion implanter 'EXCEED 3000AH Evo2'  

SciTech Connect (OSTI)

High productivity medium current ion implanter 'EXCEED 3000AH Evo2' is developed. In semiconductor manufacturing field, improvement of the productivity is continuously required. Especially mass production lines recently tend to use low energy beam and 2 pass implant for higher throughput. The 'Evo2' has been developed in an effort to fulfill these requirements. The 'Evo2' increases low energy beam current by 150 to 250% by applying electrostatic einzel lens called 'V-lens' installed at the exit of the Collimator magnet. This lens is also able to control the beam incident angle by adjusting the upper and lower electrode's voltages independently. Besides, mechanical scanning speed is enhanced to minimize process time of 2 pass implant, while also frequency of the fast beam scanning is enhanced to keep dose uniformity. In addition, a vacuum pumping capability at the target chamber is enhanced to reduce a vacuum waiting time during processing photo-resist wafers. This improvement achieved to reduce process time by 40% for a specific recipe. Furthermore, a modified Indirectly Heated Cathode with electron active Reflection 2 (IHC-R2) ion source which has a long life time filament has been installed. These new elements and/or functions have realized typically 25% improvement of productivity compared to standard EXCEED, and also improve a precise implantation capability.

Ikejiri, T.; Hamamoto, N.; Hisada, S.; Iwasawa, K.; Kawakami, K.; Kokuryu, K.; Miyamoto, N.; Nogami, T.; Sakamoto, T.; Sasada, Y.; Tanaka, K.; Yamamoto, Y.; Yamashita, T. [Nissin Ion Equipment Co., LTD., 575, Kuze-tonoshiro-cho, Minami-ku, Kyoto, 601-8205 (Japan)

2011-01-07T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Quantum mutual information of an entangled state propagating through a fast-light medium  

E-Print Network [OSTI]

Although it is widely accepted that classical information cannot travel faster than the speed of light in vacuum, the behavior of quantum correlations and quantum information propagating through actively-pumped fast-light media has not been studied in detail. To investigate this behavior, we send one half of an entangled state of light through a gain-assisted fast-light medium and detect the remaining quantum correlations. We show that the quantum correlations can be advanced by a small fraction of the correlation time while the entanglement is preserved even in the presence of noise added by phase-insensitive gain. Additionally, although we observe an advance of the peak of the quantum mutual information between the modes, we find that the degradation of the mutual information due to the added noise appears to prevent an advancement of the leading edge. In contrast, we show that both the leading and trailing edges of the mutual information in a slow-light system can be significantly delayed.

Jeremy B. Clark; Ryan T. Glasser; Quentin Glorieux; Ulrich Vogl; Tian Li; Kevin M. Jones; Paul D. Lett

2014-05-29T23:59:59.000Z

342

Medium Truck Duty Cycle Data from Real-World Driving Environments: Project Interim Report  

SciTech Connect (OSTI)

Since the early part of the 20th century, the US trucking industry has provided a safe and economical means of moving commodities across the country. At the present time, nearly 80% of the US domestic freight movement involves the use of trucks. The US Department of Energy (DOE) is spearheading a number of research efforts to improve heavy vehicle fuel efficiencies. This includes research in engine technologies (including hybrid and fuel cell technologies), lightweight materials, advanced fuels, and parasitic loss reductions. In addition, DOE is developing advanced tools and models to support heavy vehicle truck research, and is leading the 21st Century Truck Partnership whose stretch goals involve a reduction by 50% of the fuel consumption of heavy vehicles on a ton-mile basis. This Medium Truck Duty Cycle (MTDC) Project is a critical element in DOE s vision for improved heavy vehicle energy efficiency and is unique in that there is no other national database of characteristic duty cycles for medium trucks. It involves the collection of real-world data for various situational characteristics (rural/urban, freeway/arterial, congested/free-flowing, good/bad weather, etc.) and looks at the unique nature of medium trucks drive cycles (stop-and-go delivery, power takeoff, idle time, short-radius trips), to provide a rich source of data that can contribute to the development of new tools for fuel efficiency and modeling, provide DOE a sound basis upon which to make technology investment decisions, and provide a national archive of real-world-based medium-truck operational data to support heavy vehicle energy efficiency research. The MTDC project involves a two-part field operational test (FOT). For the Part-1 FOT, three vehicles, each from two vocations (urban transit and dry-box delivery) were instrumented for one year of data collection. The Part-2 FOT will involve the towing/recovery and utility vocations. The vehicles participating in the MTDC project are doing so through gratis partnerships in return for early access to the results of this study. Partnerships such as these are critical to FOTs in which real-world data is being collected. In Part 1 of the project, Oak Ridge National Laboratory(ORNL) established partnerships with the H.T. Hackney Company, one of the largest wholesale distributors in the country, distributing products to 21 states; and with the Knoxville Area Transit (KAT), the City of Knoxville s transit system, operating services across the city of Knoxville and parts of Knox co. These partnerships and agreements provided ORNL access to three Class-7 2005/2007 International day-cab tractors, model 8600, which regularly haul 28 ft pup trailers (H.T. Hackney Co) and three Class-7 2005 Optima LF-34 buses (KAT), for collection of duty cycle data. In addition, ORNL has collaborated with the Federal Motor Carrier Safety Administration (FMCSA) to determine if there were possible synergies between this duty cycle data collection effort and FMCSA s need to learn more about the operation and duty cycles of the second-largest fuel consuming commercial vehicle category in the US. FMCSA s primary interest was in collecting safety data relative to the driver, carrier, and vehicle. In order to collect the duty cycle and safety-related data, ORNL developed a data acquisition and wireless communication system that was placed on each test vehicle. Each signal recorded in this FOT was collected by means of one of the instruments incorporated into each data acquisition system (DAS). Native signals were obtained directly from the vehicle s J1939 and J1708 data buses. A VBOX II Lite collected Global Positioning System related information including speed, acceleration, and spatial location information at a rate of 5 Hz, and communicated this data via the CAN (J1939) protocol. The Air-Weigh LoadMaxx, a self-weighing system which determines the vehicle s gross weight by means of pressure transducers and posts the weight to the vehicle s J1939 data bus, was used to collect vehicle payload information. A cellular modem, the Raven X

Franzese, Oscar [ORNL; Lascurain, Mary Beth [ORNL; Capps, Gary J [ORNL

2011-01-01T23:59:59.000Z

343

Evaluation of fuel consumption potential of medium and heavy duty vehicles through modeling and simulation.  

SciTech Connect (OSTI)

The main objective of this report is to provide quantitative data to support the Committee in its task of establishing a report to support rulemaking on medium- and heavy-duty fuel efficiency improvement. In particular, it is of paramount importance for the Committee to base or illustrate their conclusions on established models and actual state-of-the art data. The simulations studies presented in the report have been defined and requested by the members of the National Academy committee to provide quantitative inputs to support their recommendations. As such, various technologies and usage scenarios were considered for several applications. One of the objective is to provide the results along with their associated assumptions (both vehicle and drive cycles), information generally missing from public discussions on literature search. Finally, the advantages and limitations of using simulation will be summarized. The study addresses several of the committee tasks, including: (1) Discussion of the implication of metric selection; (2) Assessing the impact of existing technologies on fuel consumption through energy balance analysis (both steady-state and standard cycles) as well as real world drive cycles; and (3) Impact of future technologies, both individually and collectively.

Delorme, A.; Karbowski, D.; Sharer, P.; Energy Systems

2010-03-31T23:59:59.000Z

344

PAPER-64 Constraints On Reionization II: The Temperature Of The z=8.4 Intergalactic Medium  

E-Print Network [OSTI]

We present constraints on both the kinetic temperature of the intergalactic medium (IGM) at z=8.4, and on models for heating the IGM at high-redshift with X-ray emission from the first collapsed objects. These constraints are derived using a semi-analytic method to explore the new measurements of the 21 cm power spectrum from the Donald C. Backer Precision Array for Probing the Epoch of Reionization (PAPER), which were presented in a companion paper, Ali et al. (2015). Twenty-one cm power spectra with amplitudes of hundreds of mK^2 can be generically produced if the kinetic temperature of the IGM is significantly below the temperature of the Cosmic Microwave Background (CMB); as such, the new results from PAPER place lower limits on the IGM temperature at z=8.4. Allowing for the unknown ionization state of the IGM, our measurements find the IGM temperature to be above ~5 K for neutral fractions between 10% and 85%, above ~7 K for neutral fractions between 15% and 80%, or above ~10 K for neutral fractions betw...

Pober, Jonathan C; Parsons, Aaron R; McQuinn, Matthew; Aguirre, James E; Bernardi, Gianni; Bradley, Richard F; Carilli, Chris L; Cheng, Carina; DeBoer, David R; Dexter, Matthew R; Furlanetto, Steven R; Grobbelaar, Jasper; Horrell, Jasper; Jacobs, Daniel C; Klima, Patricia J; Kohn, Saul A; Liu, Adrian; MacMahon, David H E; Maree, Matthys; Mesinger, Andrei; Moore, David F; Razavi-Ghods, Nima; Stefan, Irina I; Walbrugh, William P; Walker, Andre; Zheng, Haoxuan

2015-01-01T23:59:59.000Z

345

Medium-resolution Autonomous in situ Gamma Detection System for Marine and Coastal Waters  

SciTech Connect (OSTI)

We are developing a medium-resolution autonomous in situ gamma detection system for marine and coastal waters. The system is designed to extract and preconcentrate isotopes of interest from natural waters prior to detection in order to eliminate signal attenuation of the gamma rays traveling through water and lower the overall background due to the presence of naturally occurring radioactive isotopes (40K and U/Th series radionuclides). Filtration is used to preconcentrate target isotopes residing on suspended particles, while chemosorption is employed to preferentially extract truly dissolved components from the water column. A variety of commercial and in-house nano-porus chemosorbents have been selected, procured or produced, and tested. Used filter and chemosorbent media are counted autonomously using two LaBr3 detectors in a near 4-pi configuration around the samples. A compact digital pulse processing system developed in-house and capable of running in coincidence mode is used to process the signal from the detectors to a small on-board computer. The entire system is extremely compact (9” dia. x 30” len.) and platform independent, but designed for initial deployment on a research buoy.

Schwantes, Jon M.; Addleman, Raymond S.; Davidson, Joseph D.; Douglas, Matthew; Meier, David E.; Mullen, O Dennis; Myjak, Mitchell J.; Jones, Mark E.; Woodring, Mitchell L.; Johnson, Bryce; Santschi, Peter H.

2009-12-01T23:59:59.000Z

346

Lead iron phosphate glass as a containment medium for disposal of high-level nuclear waste  

DOE Patents [OSTI]

Lead-iron phosphate glasses containing a high level of Fe.sub.2 O.sub.3 for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a highly corrosion resistant, homogeneous, easily processed glass can be formed. For corroding solutions at 90.degree. C., with solution pH values in the range between 5 and 9, the corrosion rate of the lead-iron phosphate nuclear waste glass is at least 10.sup.2 to 10.sup.3 times lower than the corrosion rate of a comparable borosilicate nuclear waste glass. The presence of Fe.sub.2 O.sub.3 in forming the lead-iron phosphate glass is critical. Lead-iron phosphate nuclear waste glass can be prepared at temperatures as low as 800.degree. C., since they exhibit very low melt viscosities in the 800.degree. to 1050.degree. C. temperature range. These waste-loaded glasses do not readily devitrify at temperatures as high as 550.degree. C. and are not adversely affected by large doses of gamma radiation in H.sub.2 O at 135.degree. C. The lead-iron phosphate waste glasses can be prepared with minimal modification of the technology developed for processing borosilicate glass nuclear wasteforms.

Boatner, Lynn A. (Oak Ridge, TN); Sales, Brian C. (Oak Ridge, TN)

1989-01-01T23:59:59.000Z

347

Analysis of the growth of strike-slip faults using effective medium theory  

SciTech Connect (OSTI)

Increases in the dimensions of strike-slip faults including fault length, thickness of fault rock and the surrounding damage zone collectively provide quantitative definition of fault growth and are commonly measured in terms of the maximum fault slip. The field observations indicate that a common mechanism for fault growth in the brittle upper crust is fault lengthening by linkage and coalescence of neighboring fault segments or strands, and fault rock-zone widening into highly fractured inner damage zone via cataclastic deformation. The most important underlying mechanical reason in both cases is prior weakening of the rocks surrounding a fault's core and between neighboring fault segments by faulting-related fractures. In this paper, using field observations together with effective medium models, we analyze the reduction in the effective elastic properties of rock in terms of density of the fault-related brittle fractures and fracture intersection angles controlled primarily by the splay angles. Fracture densities or equivalent fracture spacing values corresponding to the vanishing Young's, shear, and quasi-pure shear moduli were obtained by extrapolation from the calculated range of these parameters. The fracture densities or the equivalent spacing values obtained using this method compare well with the field data measured along scan lines across the faults in the study area. These findings should be helpful for a better understanding of the fracture density/spacing distribution around faults and the transition from discrete fracturing to cataclastic deformation associated with fault growth and the related instabilities.

Aydin, A.; Berryman, J.G.

2009-10-15T23:59:59.000Z

348

The in-medium heavy quark potential from quenched and dynamical lattice QCD  

E-Print Network [OSTI]

We present our latest results for the the complex valued static heavy-quark potential at finite temperature from lattice QCD. The real and imaginary part of the potential are obtained from the position and width of the lowest lying peak in the spectral function of the Wilson line correlator in Coulomb gauge. Spectral information is extracted from Euclidean time data using a novel Bayesian approach different from the Maximum Entropy Method. In order to extract both the real and imaginary part, we generated anisotropic quenched lattices $32^3\\times N_\\tau$ $(\\beta=7.0,\\xi=3.5)$ with $N_\\tau=24,\\ldots,96$, corresponding to $839{\\rm MeV} \\geq T\\geq 210 {\\rm MeV}$. For the case of a realistic QCD medium with light u, d and s quarks we use isotropic $48^3\\times12$ ASQTAD lattices with $m_l=m_s/20$ provided by the HotQCD collaboration, which span $286 {\\rm MeV} \\geq T\\geq 148{\\rm MeV}$. We find a clean transition from a confining to a Debye screened real part and observe that its values lie close to the color singlet free energies in Coulomb gauge. The imaginary part, estimated on quenched lattices, is found to be of the same order of magnitude as in hard-thermal loop (HTL) perturbation theory.

Yannis Burnier; Olaf Kaczmarek; Alexander Rothkopf

2014-10-27T23:59:59.000Z

349

Fleet test evaluations of an automotive and medium-duty truck coolant filter conditioner  

SciTech Connect (OSTI)

The use of coolant filtration and supplemental coolant additives (SCA) to replenish depleted protective chemistry has been applied in the heavy duty diesel arena for many years. Some filtration of coolant and SCA usage in light gasoline engine and automotive diesel engine vehicles has taken place using off-board equipment to filter and recondition coolant. As concerns about the environment have increased, disposal of spent coolant that is replaced on a scheduled basis is a burden on fleets as well as individuals. In addition, as the efforts by vehicle manufacturers to extend or eliminate routine service intervals of vehicle systems increase, the use of an on-board system has become more attractive. A number of filtration/conditioning designs have been developed for light and medium duty use and have been on field tests for over a year. These field tests are described and reported, along with background on the filter design and chemistry package used. Field testing included: low and high mileage vehicles; newer and older vehicles; well and poorly maintained vehicles; and an assessment of the possibility of overcharging of the coolant chemistry.

Wright, A.B. [AlliedSignal Filters and Spark Plugs, Perrysburg, OH (United States)

1999-08-01T23:59:59.000Z

350

Truck Essential Power Systems Efficiency Improvements for Medium-Duty Trucks  

SciTech Connect (OSTI)

With a variety of hybrid vehicles available in the passenger car market, electric technologies and components of that scale are becoming readily available. Commercial vehicle segments have lagged behind passenger car markets, leaving opportunities for component and system development. Escalating fuel prices impact all markets and provide motivation for OEMs, suppliers, customers, and end-users to seek new techniques and technologies to deliver reduced fuel consumption. The research presented here specifically targets the medium-duty (MD), Class 4-7, truck market with technologies aimed at reducing fuel consumption. These technologies could facilitate not only idle, but also parasitic load reductions. The development efforts here build upon the success of the More Electric Truck (MET) demonstration program at Caterpillar Inc. Employing a variety of electric accessories, the MET demonstrated the improvement seen with such technologies on a Class 8 truck. The Truck Essential Power Systems Efficiency Improvements for Medium-Duty Trucks (TEPS) team scaled the concepts and successes of MET to a MD chassis. The team designed an integrated starter/generator (ISG) package and energy storage system (ESS), explored ways to replace belt and gear-driven accessory systems, and developed supervisory control algorithms to direct the usage of the generated electricity and system behavior on the vehicle. All of these systems needed to fit within the footprint of a MD vehicle and be compatible with the existing conventional systems to the largest extent possible. The overall goal of this effort was to demonstrate a reduction in fuel consumption across the drive cycle, including during idle periods, through truck electrification. Furthermore, the team sought to evaluate the benefits of charging the energy storage system during vehicle braking. The vehicle features an array of electric accessories facilitating on-demand, variable actuation. Removal of these accessories from the belt or geartrain of the engine yields efficiency improvements for the engine while freeing those accessories to perform at their individual peak efficiencies to meet instantaneous demand. The net result is a systems approach to fuel usage optimization. Unique control algorithms were specifically developed to capitalize on the flexibility afforded by the TEPS architecture. Moreover, the TEPS truck technology mixture exhibits a means to supplant current accessory power sources such as on-board or trailer-mounted gasoline-powered generators or air compressors. Such functionality further enhances the value of the electric systems beyond the fuel savings alone. To demonstrate the fuel economy improvement wrought via the TEPS components, vehicle fuel economy testing was performed on the nearly stock (baseline) truck and the TEPS truck. Table 1 illustrates the fuel economy gains produced by the TEPS truck electrification. While the fuel economy results shown in Table 1 do reflect specific test conditions, they show that electrification of accessory hardware can yield significant fuel savings. In this case, the savings equated to a 15 percent reduction in fuel consumption during controlled on-road testing. Truck electrification allows engine shutdown during idle conditions as well as independent on-demand actuation of accessory systems. In some cases, independent actuation may even include lack of operation, a feature not always present in mechanically driven components. This combination of attributes allows significant improvements in system efficiency and the fuel economy improvements demonstrated by the TEPS team.

Larry Slone; Jeffery Birkel

2007-12-31T23:59:59.000Z

351

COSMOLOGICAL SIMULATIONS OF INTERGALACTIC MEDIUM EVOLUTION. I. TEST OF THE SUBGRID CHEMICAL ENRICHMENT MODEL  

SciTech Connect (OSTI)

We present a one-zone galactic chemical enrichment model that takes into account the contribution of stellar winds from massive stars under the effect of rotation, Type II supernovae, hypernovae, stellar winds from low- and intermediate-mass stars, and Type Ia supernovae. This enrichment model will be implemented in a galactic model designed to be used as a subgrid treatment for galaxy evolution and outflow generation in large-scale cosmological simulations, in order to study the evolution of the intergalactic medium. We test our enrichment prescription by comparing its predictions with the metallicity distribution function and the abundance patterns of 14 chemical elements observed in the Milky Way stars. To do so, we combine the effect of many stellar populations created from the star formation history of the Galaxy in the solar neighborhood. For each stellar population, we keep track of its specific mass, initial metallicity, and age. We follow the time evolution of every population in order to respect the time delay between the various stellar phases. Our model is able to reproduce the observed abundances of C, O, Na, Mg, Al, S, and Ca. For Si, Cr, Mn, Ni, Cu, and Zn, the fits are still reasonable, but improvements are needed. We marginally reproduce the nitrogen abundance in very low metallicity stars. Overall, our results are consistent with the predicted abundance ratios seen in previous studies of the enrichment history of the Milky Way. We have demonstrated that our semi-analytic one-zone model, which cannot deal with spatial information such as the metallicity gradient, can nevertheless successfully reproduce the global Galactic enrichment evolution obtained by more complex models, at a fraction of the computational cost. This model is therefore suitable for a subgrid treatment of chemical enrichment in large-scale cosmological simulations.

Côté, Benoit; Martel, Hugo; Drissen, Laurent [Département de physique, de Génie Physique et d'Optique, Université Laval, Québec, QC G1V 0A6 (Canada)

2013-11-10T23:59:59.000Z

352

Application of a medium-range global hydrologic probabilistic forecast scheme to the Ohio River Basin  

SciTech Connect (OSTI)

A 10-day globally applicable flood prediction scheme was evaluated using the Ohio River basin as a test site for the period 2003-2007. The Variable Infiltration Capacity (VIC) hydrology model was initialized with the European Centre for Medium Range Weather Forecasts (ECMWF) analysis temperatures and wind, and Tropical Rainfall Monitoring Mission Multi Satellite Precipitation Analysis (TMPA) precipitation up to the day of forecast. In forecast mode, the VIC model was then forced with a calibrated and statistically downscaled ECMWF ensemble prediction system (EPS) 10-day ensemble forecast. A parallel set up was used where ECMWF EPS forecasts were interpolated to the spatial scale of the hydrology model. Each set of forecasts was extended by 5 days using monthly mean climatological variables and zero precipitation in order to account for the effect of initial conditions. The 15-day spatially distributed ensemble runoff forecasts were then routed to four locations in the basin, each with different drainage areas. Surrogates for observed daily runoff and flow were provided by the reference run, specifically VIC simulation forced with ECMWF analysis fields and TMPA precipitation fields. The flood prediction scheme using the calibrated and downscaled ECMWF EPS forecasts was shown to be more accurate and reliable than interpolated forecasts for both daily distributed runoff forecasts and daily flow forecasts. Initial and antecedent conditions dominated the flow forecasts for lead times shorter than the time of concentration depending on the flow forecast amounts and the drainage area sizes. The flood prediction scheme had useful skill for the 10 following days at all sites.

Voisin, Nathalie; Pappenberger, Florian; Lettenmaier, D. P.; Buizza, Roberto; Schaake, John

2011-08-15T23:59:59.000Z

353

ON THE AMPLIFICATION OF MAGNETIC FIELD BY A SUPERNOVA BLAST SHOCK WAVE IN A TURBULENT MEDIUM  

SciTech Connect (OSTI)

We have performed extensive two-dimensional magnetohydrodynamic simulations to study the amplification of magnetic fields when a supernova blast wave propagates into a turbulent interstellar plasma. The blast wave is driven by injecting high pressure in the simulation domain. The interstellar magnetic field can be amplified by two different processes, occurring in different regions. One is facilitated by the fluid vorticity generated by the 'rippled' shock front interacting with the background turbulence. The resulting turbulent flow keeps amplifying the magnetic field, consistent with earlier work. The other process is facilitated by the growth of the Rayleigh-Taylor instability at the contact discontinuity between the ejecta and the shocked medium. This can efficiently amplify the magnetic field and tends to produce the highest magnetic field. We investigate the dependence of the amplification on numerical parameters such as grid-cell size and on various physical parameters. We show that the magnetic field has a characteristic radial profile such that the downstream magnetic field gets progressively stronger away from the shock. This is because the downstream magnetic field needs a finite time to reach the efficient amplification, and will get further amplified in the Rayleigh-Taylor region. In our simulation, we do not observe a systematic strong magnetic field within a small distance to the shock. This indicates that if the magnetic-field amplification in supernova remnants indeed occurs near the shock front, other processes such as three-dimensional instabilities, plasma kinetics, and/or cosmic ray effect may need to be considered to explain the strong magnetic field in supernova remnants.

Guo Fan; Li Shengtai; Li Hui; Li, David [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Giacalone, Joe; Jokipii, J. R. [Department of Planetary Sciences and Lunar and Planetary Laboratory, University of Arizona, 1629 E. University Blvd., Tucson, AZ 85721 (United States)

2012-03-10T23:59:59.000Z

354

The energy dependence of lithium formate and alanine EPR dosimeters for medium energy x rays  

SciTech Connect (OSTI)

Purpose: To perform a systematic investigation of the energy dependence of alanine and lilthium formate EPR dosimeters for medium energy x rays. Methods: Lithium formate and alanine EPR dosimeters were exposed to eight different x-ray beam qualities, with nominal potentials ranging from 50 to 200 kV. Following ionometry based on standards of absorbed dose to water, the dosimeters were given two different doses of approximately 3 and 6 Gy for each radiation quality, with three dosimeters for each dose. A reference series was also irradiated to three different dose levels at a {sup 60}Co unit. The dose to water energy response, that is, the dosimeter reading per absorbed dose to water relative to that for {sup 60}Co {gamma}-rays, was estimated for each beam quality. In addition, the energy response was calculated by Monte Carlo simulations and compared to the experimental energy response. Results: The experimental energy response estimates ranged from 0.89 to 0.94 and from 0.68 to 0.90 for lithium formate and alanine, respectively. The uncertainties in the experimental energy response estimates were typically 3%. The relative effectiveness, that is, the ratio of the experimental energy response to that following Monte Carlo simulations was, on average, 0.96 and 0.94 for lithium formate and alanine, respectively. Conclusions: This work shows that lithium formate dosimeters are less dependent on x-ray energy than alanine. Furthermore, as the relative effectiveness for both lithium formate and alanine were systematically less than unity, the yield of radiation-induced radicals is decreased following x-irradiation compared to irradiation with {sup 60}Co {gamma}-rays.

Waldeland, Einar; Hole, Eli Olaug; Sagstuen, Einar; Malinen, Eirik [Department of Medical Physics, Norwegian Radium Hospital, Oslo University Hospital, N-0310 Oslo (Norway) and Department of Physics, University of Oslo, P.O. Box 1048, Blindern, N-0316 Oslo (Norway); Department of Physics, University of Oslo, P.O. Box 1048, Blindern, N-0316 Oslo (Norway); Department of Medical Physics, Norwegian Radium Hospital, Oslo University Hospital, N-0310 Oslo (Norway) and Department of Physics, University of Oslo, P.O. Box 1048, Blindern, N-0316 Oslo (Norway)

2010-07-15T23:59:59.000Z

355

Nonlinear instability of an Oldroyd elastico–viscous magnetic nanofluid saturated in a porous medium  

SciTech Connect (OSTI)

Through viscoelastic potential theory, a Kelvin-Helmholtz instability of two semi-infinite fluid layers, of Oldroydian viscoelastic magnetic nanofluids (MNF), is investigated. The system is saturated by porous medium through two semi-infinite fluid layers. The Oldroyd B model is utilized to describe the rheological behavior of viscoelastic MNF. The system is influenced by uniform oblique magnetic field that acts at the surface of separation. The model is used for the MNF incorporated the effects of uniform basic streaming and viscoelasticity. Therefore, a mathematical simplification must be considered. A linear stability analysis, based upon the normal modes analysis, is utilized to find out the solutions of the equations of motion. The onset criterion of stability is derived; analytically and graphs have been plotted by giving numerical values to the various parameters. These graphs depict the stability characteristics. Regions of stability and instability are identified and discussed in some depth. Some previous studies are recovered upon appropriate data choices. The stability criterion in case of ignoring the relaxation stress times is also derived. To relax the mathematical manipulation of the nonlinear approach, the linearity of the equations of motion is taken into account in correspondence with the nonlinear boundary conditions. Taylor's theory is adopted to expand the governing nonlinear characteristic equation according to of the multiple time scales technique. This analysis leads to the well-known Ginzburg–Landau equation, which governs the stability criteria. The stability criteria are achieved theoretically. To simplify the mathematical manipulation, a special case is considered to achieve the numerical estimations. The influence of orientation of the magnetic fields on the stability configuration, in linear as well as nonlinear approaches, makes a dual role for the magnetic field strength in the stability graphs. Stability diagram is plotted for different sets of physical parameters. A new stability as well as instability region, in the parameter space, appears due to the nonlinear effects.

Moatimid, Galal M., E-mail: gal-moa@hotmail.com [Department of Mathematics, Faculty of Education, Ain Shams University, Roxy (Egypt); Alali, Elham M. M., E-mail: dr-elham-alali@hotmail.com; Ali, Hoda S. M., E-mail: hoda-ali-1@hotmail.com [Department of Mathematics, Faculty of Science (Girls Branch), University of Tabuk, Tabuk, P.O. Box 741 (Saudi Arabia)

2014-09-15T23:59:59.000Z

356

MAGIICAT II. GENERAL CHARACTERISTICS OF THE Mg II ABSORBING CIRCUMGALACTIC MEDIUM  

SciTech Connect (OSTI)

We examine the Mg II absorbing circumgalactic medium (CGM) for the 182 intermediate redshift (0.072 ? z ? 1.120) galaxies in the 'Mg II Absorber-Galaxy Catalog' (MAGIICAT). We parameterize the anti-correlation between equivalent width, W{sub r} (2796), and impact parameter, D, with a log-linear fit, and show that a power law poorly describes the data. We find that higher luminosity galaxies have larger W{sub r} (2796) at larger D (4.3?). The covering fractions, f{sub c} , decrease with increasing D and W{sub r} (2796) detection threshold. Higher luminosity galaxies have larger f{sub c} ; no absorption is detected in lower luminosity galaxies beyond 100 kpc. Bluer and redder galaxies have similar f{sub c} for D < 100 kpc, but for D > 100 kpc, bluer galaxies have larger f{sub c} , as do higher redshift galaxies. The 'absorption radius', R(L) = R{sub *}(L/L*){sup ?}, which we examine for four different W{sub r} (2796) detection thresholds, is more luminosity sensitive to the B-band than the K-band, more sensitive for redder galaxies than for bluer galaxies, and does not evolve with redshift for the K-band, but becomes more luminosity sensitive toward lower redshift for the B-band. These trends clearly indicate a more extended Mg II absorbing CGM around higher luminosity, bluer, and higher redshift galaxies. Several of our findings are in conflict with other works. We address these conflicts and discuss the implications of our results for the low-ionization, intermediate redshift CGM.

Nielsen, Nikole M.; Churchill, Christopher W. [New Mexico State University, Las Cruces, NM 88003 (United States); Kacprzak, Glenn G., E-mail: nnielsen@nmsu.edu, E-mail: cwc@nmsu.edu, E-mail: gkacprzak@astro.swin.edu.au [Swinburne University of Technology, Victoria 3122 (Australia)

2013-10-20T23:59:59.000Z

357

Continued development of a semianalytical solution for two-phase fluid and heat flow in a porous medium  

SciTech Connect (OSTI)

Over the past few years the authors have developed a semianalytical solution for transient two-phase water, air, and heat flow in a porous medium surrounding a constant-strength linear heat source, using a similarity variable {eta} = r/{radical}t. Although the similarity transformation approach requires a simplified geometry, all the complex physical mechanisms involved in coupled two-phase fluid and heat flow can be taken into account in a rigorous way, so that the solution may be applied to a variety of problems of current interest. The work was motivated by adverse to predict the thermohydrological response to the proposed geologic repository for heat-generating high-level nuclear wastes at Yucca Mountain, Nevada, in a partially saturated, highly fractured volcanic formation. The paper describes thermal and hydrologic conditions near the heat source; new features of the model; vapor pressure lowering; and the effective-continuum representation of a fractured/porous medium.

Doughty, C.; Pruess, K. [Lawrence Berkeley Lab., CA (United States)

1991-06-01T23:59:59.000Z

358

Dynamical Evolution, Hadronization and Angular De-correlation of Heavy Flavor in a Hot and Dense QCD Medium  

E-Print Network [OSTI]

We study heavy flavor evolution and hadronization in relativistic heavy-ion collisions. The in-medium evolution of heavy quarks is described using our modified Langevin framework that incorporates both collisional and radiative energy loss mechanisms. The subsequent hadronization process for heavy quarks is calculated with a fragmentation plus recombination model. We find significant contribution from gluon radiation to heavy quark energy loss at high $p_T$; the recombination mechanism can greatly enhance D meson production at medium $p_T$. Our calculation provides a good description of D meson nuclear modification at the LHC. In addition, we explore the angular correlation functions of heavy flavor pairs which may provide us a potential candidate for distinguishing different energy loss mechanisms of heavy quarks inside QGP.

Shanshan Cao; Guang-You Qin; Steffen A Bass

2014-04-03T23:59:59.000Z

359

Electrochemical corrosion behavior of biomedical Ti22Nb and Ti22Nb6Zr alloys in saline medium  

E-Print Network [OSTI]

Electrochemical corrosion behavior of biomedical Ti­22Nb and Ti­22Nb­6Zr alloys in saline medium B addition and potentiodynamic polarization on the microstructure and corrosion resistance of Ti­22Nb and Ti­22Nb­6Zr alloy samples.The corrosion tests were carried out in 0.9% NaCl at 37 8C and neutral p

Zheng, Yufeng

360

Dietary long-chain, but not medium-chain, triglycerides impair exercise performance and uncouple cardiac mitochondria in rats  

E-Print Network [OSTI]

RESEARCH Open Access Dietary long-chain, but not medium-chain, triglycerides impair exercise performance and uncouple cardiac mitochondria in rats Andrew J Murray*, Nicholas S Knight, Sarah E Little, Lowri E Cochlin, Mary Clements and Kieran Clarke... mitochondria were mea- sured using a Clark-type oxygen electrode (Strathkelvin Instruments Ltd, Glasgow, UK), as described previously [18]. The chambers were treated identically throughout the experiment, except that one contained 1 ?mol GDP added...

Murray, Andrew J; Knight, Nicholas S; Little, Sarah E; Cochlin, Lowri E; Clements, Mary; Clarke, Kieran

2011-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Design principle and calculations of a Scheffler fixed focus concentrator for medium temperature applications  

SciTech Connect (OSTI)

Scheffler fixed focus concentrators are successfully used for medium temperature applications in different parts of the world. These concentrators are taken as lateral sections of paraboloids and provide fixed focus away from the path of incident beam radiations throughout the year. The paper presents a complete description about the design principle and construction details of an 8 m{sup 2} surface area Scheffler concentrator. The first part of the paper presents the mathematical calculations to design the reflector parabola curve and reflector elliptical frame with respect to equinox (solar declination = 0) by selecting a specific lateral part of a paraboloid. Crossbar equations and their ellipses, arc lengths and their radii are also calculated to form the required lateral section of the paraboloid. Thereafter, the seasonal parabola equations are calculated for two extreme positions of summer and winter in the northern hemisphere (standing reflectors). The slopes of the parabola equations for equinox (solar declination = 0), summer (solar declination = +23.5) and winter (solar declination = -23.5) for the Scheffler reflector (8 m{sup 2} surface area) are calculated to be 0.17, 0.28, and 0.13 respectively. The y-intercepts of the parabola equations for equinox, summer and winter are calculated as 0, 0.54, and -0.53 respectively. By comparing with the equinox parabola curve, the summer parabola is found to be smaller in size and uses the top part of the parabola curve while the winter parabola is bigger in size and uses the lower part of the parabola curve to give the fixed focus. For this purpose, the reflector assembly is composed of flexible crossbars and a frame to induce the required change of the parabola curves with the changing solar declination. The paper also presents the calculation procedure of seasonal parabola equations for standing reflectors in the southern hemisphere as well as for laying reflectors in the northern and southern hemispheres. Highly reflective aluminium sheets are used on the crossbar profiles to complete the concentrator. The reflector is installed at the required site by setting its axis of rotation at an angle equal to the latitude of the site. For daily tracking, these concentrators rotate along an axis parallel to the polar axis of the earth at an angular velocity of one revolution per day with the help of simpler and cheaper self-tracking devices. For seasonal tracking, the reflector rotates at half the solar declination angle with the help of a telescopic clamp mechanism. The design procedure is simple, flexible and does not need any special computational setup, thus offering the prospect of potential application in domestic as well as industrial configurations. (author)

Munir, A.; Hensel, O. [Department of Agricultural Engineering,University of Kassel, Nordbahnhofstr. 1 a 37213 Witzenhausen (Germany); Scheffler, W. [Solar Bruecke G.v.Werdenbergstr.6 D-89344 Aislingen (Germany)

2010-08-15T23:59:59.000Z

362

Dynamics of slow light and light storage in a Doppler-broadened electromagnetically-induced-transparency medium: A numerical approach  

SciTech Connect (OSTI)

We present a numerical scheme to study the dynamics of slow light and light storage in an electromagnetically-induced-transparency (EIT) medium at finite temperatures. Allowing for the motional coupling, we derive a set of coupled Schroedinger equations describing a boosted closed three-level EIT system according to the principle of Galilean relativity. The dynamics of a uniformly moving EIT medium can thus be determined by numerically integrating the coupled Schroedinger equations for atoms plus one ancillary Maxwell-Schroedinger equation for the probe pulse. The central idea of this work rests on the assumption that the loss of ground-state coherence at finite temperatures can be ascribed to the incoherent superposition of density matrices representing the EIT systems with various velocities. Close agreements are demonstrated in comparing the numerical results with the experimental data for both slow light and light storage. In particular, the distinct characters featuring the decay of ground-state coherence can be well verified for slow light and light storage. This warrants that the current scheme can be applied to determine the decaying profile of the ground-state coherence as well as the temperature of the EIT medium.

Su, Shih-Wei; Chen, Yi-Hsin; Yu, Ite A. [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Gou, Shih-Chuan [Department of Physics, National Changhua University of Education, Changhua 50058, Taiwan (China); Horng, Tzyy-Leng [Department of Applied Mathematics, Feng Chia University, Taichung 40074, Taiwan (China)

2011-01-15T23:59:59.000Z

363

Science Requirements and Conceptual Design for a Polarized Medium Energy Electron-Ion Collider at Jlab  

SciTech Connect (OSTI)

Researchers have envisioned an electron-ion collider with ion species up to heavy ions, high polarization of electrons and light ions, and a well-matched center-of-mass energy range as an ideal gluon microscope to explore new frontiers of nuclear science. In its most recent Long Range Plan, the Nuclear Science Advisory Committee (NSAC) of the US Department of Energy and the National Science Foundation endorsed such a collider in the form of a 'half-recommendation.' As a response to this science need, Jefferson Lab and its user community have been engaged in feasibility studies of a medium energy polarized electron-ion collider (MEIC), cost-effectively utilizing Jefferson Lab's already existing Continuous Electron Beam Accelerator Facility (CEBAF). In close collaboration, this community of nuclear physicists and accelerator scientists has rigorously explored the science case and design concept for this envisioned grand instrument of science. An electron-ion collider embodies the vision of reaching the next frontier in Quantum Chromodynamics - understanding the behavior of hadrons as complex bound states of quarks and gluons. Whereas the 12 GeV Upgrade of CEBAF will map the valence-quark components of the nucleon and nuclear wave functions in detail, an electron-ion collider will determine the largely unknown role sea quarks play and for the first time study the glue that binds all atomic nuclei. The MEIC will allow nuclear scientists to map the spin and spatial structure of quarks and gluons in nucleons, to discover the collective effects of gluons in nuclei, and to understand the emergence of hadrons from quarks and gluons. The proposed electron-ion collider at Jefferson Lab will collide a highly polarized electron beam originating from the CEBAF recirculating superconducting radiofrequency (SRF) linear accelerator (linac) with highly polarized light-ion beams or unpolarized light- to heavy-ion beams from a new ion accelerator and storage complex. Since the very beginning, the design studies at Jefferson Lab have focused on achieving high collider performance, particularly ultrahigh luminosities up to 10{sup 34} cm{sup -2}s{sup -1} per detector with large acceptance, while maintaining high polarization for both the electron and light-ion beams. These are the two key performance requirements of a future electron-ion collider facility as articulated by the NSAC Long Range Plan. In MEIC, a new ion complex is designed specifically to deliver ion beams that match the high bunch repetition and highly polarized electron beam from CEBAF. During the last two years, both development of the science case and optimization of the machine design point toward a medium-energy electron-ion collider as the topmost goal for Jefferson Lab. The MEIC, with relatively compact collider rings, can deliver a luminosity above 10{sup 34} cm{sup -2}s{sup -1} at a center-of-mass energy up to 65 GeV. It offers an electron energy up to 11 GeV, a proton energy up to 100 GeV, and corresponding energies per nucleon for heavy ions with the same magnetic rigidity. This design choice balances the scope of the science program, collider capabilities, accelerator technology innovation, and total project cost. An energy upgrade could be implemented in the future by adding two large collider rings housed in another large tunnel to push the center-of-mass energy up to or exceeding 140 GeV. After careful consideration of an alternative electron energy recovery linac on ion storage ring approach, a ring-ring collider scenario at high bunch repetition frequency was found to offer fully competitive performance while eliminating the uncertainties of challenging R&D on ampere-class polarized electron sources and many-pass energy-recovery linacs (ERLs). The essential new elements of an MEIC facility at Jefferson Lab are an electron storage ring and an entirely new, modern ion acceleration and storage complex. For the high-current electron collider ring, the upgraded 12 GeV CEBAF SRF linac will serve as a full-energy injector, and, if needed, provide top

Abeyratne, S; Ahmed, S; Barber, D; Bisognano, J; Bogacz, A; Castilla, A; Chevtsov, P; Corneliussen, S; Deconinck, W; Degtiarenko, P; Delayen, J; Derbenev, Ya; DeSilva, S; Douglas, D; Dudnikov, V; Ent, R; Erdelyi, B; Evtushenko, P; Fujii, Yu; Filatov, Yury; Gaskell, D; Geng, R; Guzey, V; Horn, T; Hutton, A; Hyde, C; Johnson, R; Kim, Y; Klein, F; Kondratenko, A; Kondratenko, M; Krafft, G; Li, R; Lin, F; Manikonda, S; Marhauser, F; McKeown, R; Morozov, V; Dadel-Turonski, P; Nissen, E; Ostroumov, P; Pivi, M; Pilat, F; Poelker, M; Prokudin, A; Rimmer, R; Satogata, T; Sayed, H; Spata, M; Sullivan, M; Tennant, C; Terzic, B; Tiefenback, M; Wang, M; Wang, S; Weiss, C; Yunn, B

2012-08-01T23:59:59.000Z

365

When language policy and pedagogy conflict: pupils’ and educators’ ‘practiced language policies’ in an English-medium kindergarten classroom in Greece   

E-Print Network [OSTI]

An international school (BES) in Greece, overwhelmingly attended by Greek origin children, has adopted, as its language policy, English as the ‘official’ medium of interaction, including in the Reception classroom, the ...

Papageorgiou, Ifigenia

2012-11-28T23:59:59.000Z

366

Generation of higher order nonclassical states via interaction of intense electromagnetic field with third order nonlinear medium  

E-Print Network [OSTI]

Interaction of intense laser beam with an inversion symmetric third order nonlinear medium is modeled as a quartic anharmonic oscillator. A first order operator solution of the model Hamiltonian is used to study the possibilities of generation of higher order nonclassical states. It is found that the higher order squeezed and higher order antibunched states can be produced by this interaction. It is also shown that the higher order nonclassical states may appear separately, i.e. a higher order antibunched state is not essentially higher order squeezed state and vice versa.

Anirban Pathak

2007-02-24T23:59:59.000Z

367

Cooling rate and size effects on the medium-range structure of multicomponent oxide glasses simulated by molecular dynamics  

SciTech Connect (OSTI)

A set of molecular dynamics simulations were performed to investigate the effect of cooling rate and system size on the medium-range structure of melt-derived multicomponent silicate glasses, represented by the quaternary 45S5 Bioglass composition. Given the significant impact of the glass degradation on applications of these materials in biomedicine and nuclear waste disposal, bulk structural features which directly affect the glass dissolution process are of particular interest. Connectivity of the silicate matrix, ion clustering and nanosegregation, distribution of ring and chain structural patterns represent critical features in this context, which can be directly extracted from the models. A key issue is represented by the effect of the computational approach on the corresponding glass models, especially in light of recent indications questioning the suitability of conventional MD approaches (that is, involving melt-and-quench of systems containing ?10{sup 3} atoms at cooling rates of 5-10 K/ps) when applied to model these glasses. The analysis presented here compares MD models obtained with conventional and nonconventional cooling rates and system sizes, highlighting the trend and range of convergence of specific structural features in the medium range. The present results show that time-consuming computational approaches involving much lower cooling rates and/or significantly larger system sizes are in most cases not necessary in order to obtain a reliable description of the medium-range structure of multicomponent glasses. We identify the convergence range for specific properties and use them to discuss models of several glass compositions for which a possible influence of cooling-rate or size effects had been previously hypothesized. The trends highlighted here represent an important reference to obtain reliable models of multicomponent glasses and extract converged medium-range structural features which affect the glass degradation and thus their application in different fields. In addition, as a first application of the present findings, the fully converged structure of the 45S5 glass was further analyzed to shed new light on several dissolution-related features whose interpretation has been rather controversial in the past.

Tilocca, Antonio [Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom)] [Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom)

2013-09-21T23:59:59.000Z

368

Effective model for in-medium $\\bar{K}N$ interactions including the $L=1$ partial wave  

E-Print Network [OSTI]

Coupled channels model of meson-baryon interactions based on the effective chiral Lagrangian is extended to account explicitly for the $\\Sigma(1385)$ resonance that dominates the $P$-wave $\\bar{K}N$ and $\\pi\\Sigma$ interactions at energies below the $\\bar{K}N$ threshold. The presented model aims at a uniform treatment of the $\\Lambda(1405)$ and $\\Sigma(1385)$ dynamics in the nuclear medium. We demonstrate the applicability of the model by confronting its predictions with the vacuum scattering data, then we follow with discussing the impact of nuclear matter on the $\\pi\\Sigma$ mass spectrum and on the energy dependence of the $K^{-}p$ branching ratios.

Cieplý, Aleš

2015-01-01T23:59:59.000Z

369

Effective model for in-medium $\\bar{K}N$ interactions including the $L=1$ partial wave  

E-Print Network [OSTI]

Coupled channels model of meson-baryon interactions based on the effective chiral Lagrangian is extended to account explicitly for the $\\Sigma(1385)$ resonance that dominates the $P$-wave $\\bar{K}N$ and $\\pi\\Sigma$ interactions at energies below the $\\bar{K}N$ threshold. The presented model aims at a uniform treatment of the $\\Lambda(1405)$ and $\\Sigma(1385)$ dynamics in the nuclear medium. We demonstrate the applicability of the model by confronting its predictions with the vacuum scattering data, then we follow with discussing the impact of nuclear matter on the $\\pi\\Sigma$ mass spectrum and on the energy dependence of the $K^{-}p$ branching ratios.

Aleš Cieplý; Vojt?ch Krej?i?ík

2015-01-26T23:59:59.000Z

370

09/01/12 13:01:401 Quantifying the effects of heating temperature, and combined effects of heating medium2  

E-Print Network [OSTI]

09/01/12 13:01:401 Quantifying the effects of heating temperature, and combined effects of heating medium2 pH and recovery medium pH on the heat resistance of Salmonella typhimurium3 4 I. Leguérinel1 *, I +33 02 98 90 85 4410 E mail address: guerinel@univ-brest.fr11 Abstract12 The influence of heating

Paris-Sud XI, Université de

371

In-medium NN cross sections determined from the nuclear stopping and collective flow in heavy-ion collisions at intermediate energies  

SciTech Connect (OSTI)

In-medium nucleon-nucleon scattering cross sections are explored by comparing results of quantum molecular dynamics simulations to data on stopping and on elliptic and directed flow in intermediate-energy heavy-ion collisions. The comparison points to in-medium cross sections which are suppressed at low energies but not at higher energies. Positive correlations are found between the degree of stopping and the magnitudes of elliptic and directed flows.

Zhang Yingxun [China Institute of Atomic Energy, P.O. Box 275 (18), Beijing 102413 (China); Li Zhuxia [China Institute of Atomic Energy, P.O. Box 275 (18), Beijing 102413 (China); Center of Theoretical Nuclear Physics, National Laboratory of Lanzhou Heavy Ion Accelerator, Lanzhou 730000 (China); Institute of Theoretical Physics, Chinese Academic of Science, Beijing 100080 (China); Danielewicz, Pawel [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

2007-03-15T23:59:59.000Z

372

On the propagation of a quasi-static disturbance in a heterogeneous, deformable, and porous medium with pressure-dependent properties  

SciTech Connect (OSTI)

Using an asymptotic technique, valid when the medium properties are smoothly-varying, I derive a semi-analytic expression for the propagation velocity of a quasi-static disturbance traveling within a nonlinear-elastic porous medium. The phase, a function related to the propagation time, depends upon the properties of the medium, including the pressure-sensitivities of the medium parameters, and on pressure and displacement amplitude changes. Thus, the propagation velocity of a disturbance depends upon its amplitude, as might be expected for a nonlinear process. As a check, the expression for the phase function is evaluated for a poroelastic medium, when the material properties do not depend upon the fluid pressure. In that case, the travel time estimates agree with conventional analytic estimates, and with values calculated using a numerical simulator. For a medium with pressure-dependent permeability I find general agreement between the semi-analytic estimates and estimates from a numerical simulation. In this case the pressure amplitude changes are obtained from the numerical simulator.

Vasco, D.W.

2011-10-01T23:59:59.000Z

373

Pion-Nucleus Microscopic Optical Potential at Intermediate Energies and In-Medium Effect on the Elementary $?N$ Scattering Amplitude  

E-Print Network [OSTI]

Analysis is performed of calculations of the elastic scattering differential cross sections of pions on the $^{28}$Si, $^{40}$Ca, $^{58}$Ni and $^{208}$Pb nuclei at energies from 130 to 290 MeV basing on the microscopic optical potential (OP) constructed as an optical limit of a Glauber theory. Such an OP is defined by the corresponding target nucleus density distribution function and by the elementary $\\pi N$ amplitude of scattering. The three (say, "in-medium") parameters of the $\\pi N$ scattering amplitude: total cross section, the ratio of real to imaginary part of the forward $\\pi N$ amplitude, and the slope parameter, were obtained by fitting them to the data on the respective pion-nucleus cross sections calculated by means of the corresponding relativistic wave equation with the above OP. A difference is discussed between the best-fit "in-medium" parameters and the "free" parameters of the $\\pi N$ scattering amplitudes known from the experimental data on scattering of pions on free nucleons.

E. V. Zemlyanaya; V. K. Lukyanov; K. V. Lukyanov; E. I. Zhabitskaya; M. V. Zhabitsky

2012-10-03T23:59:59.000Z

374

Assessing the Battery Cost at Which Plug-In Hybrid Medium-Duty Parcel Delivery Vehicles Become Cost-Effective  

SciTech Connect (OSTI)

The National Renewable Energy Laboratory (NREL) validated diesel-conventional and diesel-hybrid medium-duty parcel delivery vehicle models to evaluate petroleum reductions and cost implications of hybrid and plug-in hybrid diesel variants. The hybrid and plug-in hybrid variants are run on a field data-derived design matrix to analyze the effect of drive cycle, distance, engine downsizing, battery replacements, and battery energy on fuel consumption and lifetime cost. For an array of diesel fuel costs, the battery cost per kilowatt-hour at which the hybridized configuration becomes cost-effective is calculated. This builds on a previous analysis that found the fuel savings from medium duty plug-in hybrids more than offset the vehicles' incremental price under future battery and fuel cost projections, but that they seldom did so under present day cost assumptions in the absence of purchase incentives. The results also highlight the importance of understanding the application's drive cycle specific daily distance and kinetic intensity.

Ramroth, L. A.; Gonder, J. D.; Brooker, A. D.

2013-04-01T23:59:59.000Z

375

Quality indexes based on water measurements for low and medium energy x-ray beams: A theoretical study with PENELOPE  

SciTech Connect (OSTI)

Purpose : To study the use of quality indexes based on ratios of absorbed doses in water at two different depths to characterize x-ray beams of low and medium energies. Methods : A total of 55 x-ray beam spectra were generated with the codes XCOMP5R and SPEKCALC and used as input of a series of Monte Carlo simulations performed with PENELOPE, in which the percentage depth doses in water and thek{sub Q,Q{sub 0}} factors, defined in the TRS-398 protocol, were determined for each beam. Some of these calculations were performed by simulating the ionization chamber PTW 30010. Results : The authors found that the relation betweenk{sub Q,Q{sub 0}} and the ratios of absorbed doses at two depths is almost linear. A set of ratios statistically compatible with that showing the best fit has been determined. Conclusions : The results of this study point out which of these ratios of absorbed doses in water could be used to better characterize x-ray beams of low and medium energies.

Chica, U. [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada, Spain and FISRAD S.A.S Carrera 64 a No 22-41, Bogotá D.C. (Colombia)] [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada, Spain and FISRAD S.A.S Carrera 64 a No 22-41, Bogotá D.C. (Colombia); Anguiano, M.; Lallena, A. M., E-mail: lallena@ugr.es [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain); Vilches, M. [Servicio de Radiofísica, Hospital Universitario “San Cecilio”, Avda. Dr. Olóriz, 16, E-18012 Granada (Spain)] [Servicio de Radiofísica, Hospital Universitario “San Cecilio”, Avda. Dr. Olóriz, 16, E-18012 Granada (Spain)

2014-01-15T23:59:59.000Z

376

The State of the Circumstellar Medium Surrounding Gamma-Ray Burst Sources and its Effect on the Afterglow Appearance  

E-Print Network [OSTI]

We present a numerical investigation of the contribution of the presupernova ejecta of Wolf-Rayet stars to the environment surrounding gamma-ray bursts (GRBs), and describe how this external matter can affect the observable afterglow characteristics. An implicit hydrodynamic calculation for massive stellar evolution is used here to provide the inner boundary conditions for an explicit hydrodynamical code to model the circumstellar gas dynamics. The resulting properties of the circumstellar medium are then used to calculate the deceleration of a relativistic, gas-dynamic jet and the corresponding afterglow light curve produced as the shock wave propagates through the shocked-wind medium. We find that variations in the stellar wind drive instabilities that may produce radial filaments in the shocked-wind region. These comet-like tails of clumps could give rise to strong temporal variations in the early afterglow lightcurve. Afterglows may be expected to differ widely among themselves, depending on the angular anisotropy of the jet and the properties of the stellar progenitor; a wide diversity of behaviors may be the rule, rather than the exception.

Enrico Ramirez-Ruiz; Guillermo Garcia-Segura; Jay D. Salmonson; Brenda Perez-Rendon

2005-05-27T23:59:59.000Z

377

XMM-Newton observations of the supernova remnant IC443: I. soft X-ray emission from shocked interstellar medium  

E-Print Network [OSTI]

The shocked interstellar medium around IC443 produces strong X-ray emission in the soft energy band (E<1.5 keV). We present an analysis of such emission as observed with the EPIC MOS cameras on board the XMM-Newotn observatory, with the purpose to find clear signatures of the interactions with the interstellar medium (ISM) in the X-ray band, which may complement results obtained in other wavelenghts. We found that the giant molecular cloud mapped in CO emission is located in the foreground and gives an evident signature in the absorption of X-rays. This cloud may have a torus shape and the part of torus interacting with the IC443 shock gives rise to 2MASS-K emission in the southeast. The measured density of emitting X-ray shocked plasma increases toward the northeastern limb, where the remnant is interacting with an atomic cloud. We found an excellent correlation between emission in the 0.3-0.5 keV band and bright optical/radio filament on large spatial scales. The partial shell structure seen in this band therefore traces the encounter with the atomic cloud.

E. Troja; F. Bocchino; F. Reale

2006-06-13T23:59:59.000Z

378

The Influence of in-medium NN cross-sections, symmetry potential and impact parameter on the isospin observables  

E-Print Network [OSTI]

We explore the influence of in-medium nucleon-nucleon cross section, symmetry potential and impact parameter on isospin sensitive observables in intermediate-energy heavy-ion collisions with the ImQMD05 code, a modified version of Quantum Molecular Dynamics model. At incident velocities above the Fermi velocity, we find that the density dependence of symmetry potential plays a more important role on the double neutron to proton ratio $DR(n/p)$ and the isospin transport ratio $R_i$ than the in-medium nucleon-nucleon cross sections, provided that the latter are constrained to a fixed total NN collision rate. We also explore both $DR(n/p)$ and $R_i$ as a function of the impact parameter. Since the copious production of intermediate mass fragments is a distinguishing feature of intermediate-energy heavy-ion collisions, we examine the isospin transport ratios constructed from different groups of fragments. We find that the values of the isospin transport ratios for projectile rapidity fragments with $Z\\ge20$ are greater than those constructed from the entire projectile rapidity source. We believe experimental investigations of this phenomenon can be performed. These may provide significant tests of fragmentation time scales predicted by ImQMD calculations.

Yingxun Zhang; D. D. S. Coupland; P. Danielewicz; Zhuxia Li; Hang Liu; Fei Lu; W. G. Lynch; M. B. Tsang

2010-09-10T23:59:59.000Z

379

Overcoming the Range Limitation of Medium-Duty Battery Electric Vehicles through the use of Hydrogen Fuel-Cells  

SciTech Connect (OSTI)

Battery electric vehicles possess great potential for decreasing lifecycle costs in medium-duty applications, a market segment currently dominated by internal combustion technology. Characterized by frequent repetition of similar routes and daily return to a central depot, medium-duty vocations are well positioned to leverage the low operating costs of battery electric vehicles. Unfortunately, the range limitation of commercially available battery electric vehicles acts as a barrier to widespread adoption. This paper describes the National Renewable Energy Laboratory's collaboration with the U.S. Department of Energy and industry partners to analyze the use of small hydrogen fuel-cell stacks to extend the range of battery electric vehicles as a means of improving utility, and presumably, increasing market adoption. This analysis employs real-world vocational data and near-term economic assumptions to (1) identify optimal component configurations for minimizing lifecycle costs, (2) benchmark economic performance relative to both battery electric and conventional powertrains, and (3) understand how the optimal design and its competitiveness change with respect to duty cycle and economic climate. It is found that small fuel-cell power units provide extended range at significantly lower capital and lifecycle costs than additional battery capacity alone. And while fuel-cell range-extended vehicles are not deemed economically competitive with conventional vehicles given present-day economic conditions, this paper identifies potential future scenarios where cost equivalency is achieved.

Wood, E.; Wang, L.; Gonder, J.; Ulsh, M.

2013-10-01T23:59:59.000Z

380

INFRARED SPECTROSCOPIC SURVEY OF THE QUIESCENT MEDIUM OF NEARBY CLOUDS. I. ICE FORMATION AND GRAIN GROWTH IN LUPUS  

SciTech Connect (OSTI)

Infrared photometry and spectroscopy (1-25 ?m) of background stars reddened by the Lupus molecular cloud complex are used to determine the properties of grains and the composition of ices before they are incorporated into circumstellar envelopes and disks. H{sub 2}O ices form at extinctions of A{sub K} = 0.25 ± 0.07 mag (A{sub V} = 2.1 ± 0.6). Such a low ice formation threshold is consistent with the absence of nearby hot stars. Overall, the Lupus clouds are in an early chemical phase. The abundance of H{sub 2}O ice (2.3 ± 0.1 × 10{sup –5} relative to N{sub H}) is typical for quiescent regions, but lower by a factor of three to four compared to dense envelopes of young stellar objects. The low solid CH{sub 3}OH abundance (<3%-8% relative to H{sub 2}O) indicates a low gas phase H/CO ratio, which is consistent with the observed incomplete CO freeze out. Furthermore it is found that the grains in Lupus experienced growth by coagulation. The mid-infrared (>5 ?m) continuum extinction relative to A{sub K} increases as a function of A{sub K}. Most Lupus lines of sight are well fitted with empirically derived extinction curves corresponding to R{sub V} ? 3.5 (A{sub K} = 0.71) and R{sub V} ? 5.0 (A{sub K} = 1.47). For lines of sight with A{sub K} > 1.0 mag, the ?{sub 9.7}/A{sub K} ratio is a factor of two lower compared to the diffuse medium. Below 1.0 mag, values scatter between the dense and diffuse medium ratios. The absence of a gradual transition between diffuse and dense medium-type dust indicates that local conditions matter in the process that sets the ?{sub 9.7}/A{sub K} ratio. This process is likely related to grain growth by coagulation, as traced by the A{sub 7.4}/A{sub K} continuum extinction ratio, but not to ice mantle formation. Conversely, grains acquire ice mantles before the process of coagulation starts.

Boogert, A. C. A. [IPAC, NASA Herschel Science Center, Mail Code 100-22, California Institute of Technology, Pasadena, CA 91125 (United States); Chiar, J. E. [SETI Institute, Carl Sagan Center, 189 Bernardo Avenue, Mountain View, CA 94043 (United States); Knez, C.; Mundy, L. G. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Öberg, K. I. [Departments of Chemistry and Astronomy, University of Virginia, Charlottesville, VA 22904 (United States); Pendleton, Y. J. [Solar System Exploration Research Virtual Institute, NASA Ames Research Center, Moffett Field, CA 94035 (United States); Tielens, A. G. G. M.; Van Dishoeck, E. F., E-mail: aboogert@ipac.caltech.edu [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands)

2013-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

The Design of a Large Booster Ring for the Medium Energy Electron-Ion Collider at Jlab  

SciTech Connect (OSTI)

In this paper, we present the current design of the large booster ring for the Medium energy Electron-Ion Collider at Jefferson Lab. The booster ring takes 3 GeV protons or ions of equivalent rigidity from a pre-booster ring, and accelerates them to 20 GeV for protons or equivalent energy for light to heavy ions before sending them to the ion collider ring. The present design calls for a figure-8 shape of the ring for superior preservation of ion polarization. The ring is made of warm magnets and shares a tunnel with the two collider rings. Acceleration is achieved by warm RF systems. The linear optics has been designed with the transition energy above the highest beam energy in the ring so crossing of transition energy will be avoided. Preliminary beam dynamics studies including chromaticity compensation are presented in this paper.

Edward Nissen, Todd Satogata, Yuhong Zhang

2012-07-01T23:59:59.000Z

382

Technical Support Document: Development of the Advanced Energy Design Guide for Medium to Big Box Retail Buildings - 50% Energy Savings  

SciTech Connect (OSTI)

This Technical Support Document describes the process and methodology for the development of the Advanced Energy Design Guide for Medium to Big Box Retail Buildings: Achieving 50% Energy Savings Toward a Net Zero Energy Building (AEDG-MBBR) ASHRAE et al. (2011b). The AEDG-MBBR is intended to provide recommendations for achieving 50% whole-building energy savings in retail stores over levels achieved by following ANSI/ASHRAE/IESNA Standard 90.1-2004, Energy Standard for Buildings Except Low-Rise Residential Buildings (Standard 90.1-2004) (ASHRAE 2004b). The AEDG-MBBR was developed in collaboration with the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), the American Institute of Architects (AIA), the Illuminating Engineering Society of North America (IES), the U.S. Green Building Council (USGBC), and the U.S. Department of Energy.

Bonnema, E.; Leach, M.; Pless, S.

2013-06-01T23:59:59.000Z

383

Technical Support Document: Development of the Advanced Energy Design Guide for Medium Box Retail -- 50% Energy Savings  

SciTech Connect (OSTI)

This report provides recommendations that architects, designers, contractors, developers, owners, and lessees of medium box retail buildings can use to achieve whole-building energy savings of at least 50% over ASHRAE Standard 90.1-2004. The recommendations are given by climate zone and address building envelope, fenestration, lighting systems, HVAC systems, building automation and controls, outside air treatment, service water heating, plug loads, and photovoltaic systems. The report presents several paths to 50% savings, which correspond to different levels of integrated design. These are recommendations only, and are not part of a code or standard. The recommendations are not exhaustive, but we do try to emphasize the benefits of integrated building design, that is, a design approach that analyzes a building as a whole system, rather than as a disconnected collection of individually engineered subsystems.

Hale, E. T.; Macumber, D. L.; Long, N. L.; Griffith, B. T.; Benne, K. S.; Pless, S. D.; Torcellini, P. A.

2008-09-01T23:59:59.000Z

384

Introduction of the MC3-II/GP system, medium current ion implanter with enhanced multi-charge beam current  

SciTech Connect (OSTI)

The MC3-II/GP is a leading-edge single-wafer medium-current ion implanter, newly developed by SEN Corporation. It demonstrates exceptional productivity based on a high speed wafer-handling station and enhanced beam current. It covers a substantively wider energy range in order to fully meet advanced device requirements. Retaining the superior features of the MC3-II/WR, the MC3-II/GP provides a remarkable increase of multiply-charged beam current coupled with longer ion source lifetime. Another advanced feature of the MC3-II/GP is a 30 second or 14% reduction in auto beam setup time. These improvements enable a fabrication line to reduce the total number of ion implanters and dramatically reduce COO.

Koike, Masazumi; Sato, Fumiaki; Sano, Makoto; Kawatsu, Sho; Kariya, Hiroyuki; Kimura, Yasuhiko; Kudo, Tetsuya; Shiraishi, Miyuki; Shinozuka, Masamitsu; Takahashi, Yuji; Ishida, Yuji; Tsukihara, Mitsukuni; Ueno, Kazuyoshi; Sugitani, Michiro [SEN Corporation, 1501, Imazaike, Saijo, Ehime, 799-1362 (Japan)

2012-11-06T23:59:59.000Z

385

Quantum chemical study of the electronic properties of an Iridium-based photosensitizer bound to medium-sized silver clusters  

E-Print Network [OSTI]

The equilibrium structures and electronic excitation spectra of the Ir(III) photosensitizer Ir(ppy)$_2$(bpy)]$^+$ bound to medium-sized silver clusters Ag$_n$ ($n=$19, 20) are investigated using time-dependent density functional theory. The long-range corrected LC-BLYP approach is used with a system-specific range separation parameter. The weak physisorption of the hybrid complexes yield only small changes in the broadened absorption spectra of the hybrid system as compared with its constituents. However, the density of states as well as the fine structure of the spectra is strongly modified upon complexation. It is shown that the standard range separation parameter (0.47 bohr$^{-1}$) cannot predict these properties correctly and the optimized value of 0.16 bohr$^{-1}$ should be used instead.

Bokareva, Olga S

2015-01-01T23:59:59.000Z

386

Synchrotron based infrared imaging and spectroscopy via focal plane array on live fibroblasts in D2O enriched medium  

SciTech Connect (OSTI)

We tested the viability of using synchrotron based infrared imaging to study biochemical processes inside living cells. As a model system, we studied fibroblast cells exposed to a medium highly enriched with D2O. We could show that the experimental technique allows us to reproduce at the cellular level measurements that are normally performed on purified biological molecules. We can obtain information about lipid conformation and distribution, kinetics of hydrogen/deuterium exchange, and the formation of concentration gradients of H and O isotopes in water that are associated with cell metabolism. The implementation of the full field technique in a sequential imaging format gives a description of cellular biochemistry and biophysics that contains both spatial and temporal information.

Quaroni, Luca; Zlateva, Theodora; Sarafimov, Blagoj; Kreuzer, Helen W.; Wehbe, Katia; Hegg, Eric L.; Cinque, Gianfelice

2014-03-26T23:59:59.000Z

387

Simplified modeling of liquid sodium medium with temperature and velocity gradient using real thermal-hydraulic data. Application to ultrasonic thermometry in sodium fast reactor  

SciTech Connect (OSTI)

In the framework of the French R and D program for the Generation IV reactors and specifically for the sodium cooled fast reactors (SFR), studies are carried out on innovative instrumentation methods in order to improve safety and to simplify the monitoring of fundamental physical parameters during reactor operation. The aim of the present work is to develop an acoustic thermometry method to follow up the sodium temperature at the outlet of subassemblies. The medium is a turbulent flow of liquid sodium at 550 Degree-Sign C with temperature inhomogeneities. To understand the effect of disturbance created by this medium, numerical simulations are proposed. A ray tracing code has been developed with Matlab Copyright-Sign in order to predict acoustic paths in this medium. This complex medium is accurately described by thermal-hydraulic data which are issued from a simulation of a real experiment in Japan. The analysis of these results allows understanding the effects of medium inhomogeneities on the further thermometric acoustic measurement.

Massacret, N.; Jeannot, J. P. [DEN/DTN/STPA/LIET, CEA Cadarache, Saint Paul Lez Durance (France); Moysan, J.; Ploix, M. A.; Corneloup, G. [Aix-Marseille Univ, LMA UPR 7051 CNRS, site LCND, 13625 Aix-en-Provence (France)

2013-01-25T23:59:59.000Z

388

Heating of the Hot Intergalactic Medium by Powerful Radio Galaxies and Associated High Energy Gamma-Ray Emission  

E-Print Network [OSTI]

There is increasing evidence that some heating mechanism in addition to gravitational shock heating has been important for the hot gas inside clusters and groups of galaxies, as indicated by their observed X-ray scaling properties. While supernovae are the most obvious candidate heating sources, a number of recent studies have suggested that they may be energetically insufficient. Here we consider high-power, FRII radio galaxies and shock heating of the intracluster medium (ICM, including the case of the intergalactic medium prior to cluster formation) by their large-scale jets. Based on the observed statistics of radio galaxies in clusters and their evolution, along with the most reasonable assumptions, it is shown that they can provide the ICM with excess specific energies of 1--2 keV per particle, mainly during the redshift interval $z \\sim 1-3$. This naturally meets the requirements of cluster evolution models with non-gravitational feedback in accounting for the observed deviations in the X-ray luminosity-temperature relation. In contrast to supernovae, such large-scale jets deposit their energy directly into the low density ICM outside galaxies, and are much less susceptible to radiative losses. As a clear and potentially decisive test of this scenario, we propose the observation of `prompt' high energy gamma-rays emitted by shock-accelerated, non-thermal electrons during the epoch of ICM heating by radio galaxies, which may be feasible with the {\\it GLAST} satellite. Implications for recent detections of excess hard X-rays from groups are also discussed.

Susumu Inoue; Shin Sasaki

2001-08-01T23:59:59.000Z

389

Commercial demonstration of atmospheric medium BTU fuel gas production from biomass without oxygen the Burlington, Vermont Project  

SciTech Connect (OSTI)

The first U.S. demonstration of a gas turbine operating on fuel gas produced by the thermal gasification of biomass occurred at Battelle Columbus Labs (BCL) during 1994 using their high throughput indirect medium Btu gasification Process Research Unit (PRU). Zurn/NEPCO was retained to build a commercial scale gas plant utilizing this technology. This plant will have a throughput rating of 8 to 12 dry tons per hour. During a subsequent phase of the Burlington project, this fuel gas will be utilized in a commercial scale gas turbine. It is felt that this process holds unique promise for economically converting a wide variety of biomass feedstocks efficiently into both a medium Btu (500 Btu/scf) gas turbine and IC engine quality fuel gas that can be burned in engines without modification, derating or efficiency loss. Others are currently demonstrating sub-commercial scale thermal biomass gasification processes for turbine gas, utilizing both atmospheric and pressurized air and oxygen-blown fluid bed processes. While some of these approaches hold merit for coal, there is significant question as to whether they will prove economically viable in biomass facilities which are typically scale limited by fuel availability and transportation logistics below 60 MW. Atmospheric air-blown technologies suffer from large sensible heat loss, high gas volume and cleaning cost, huge gas compressor power consumption and engine deratings. Pressurized units and/or oxygen-blown gas plants are extremely expensive for plant scales below 250 MW. The FERCO/BCL process shows great promise for overcoming the above limitations by utilizing an extremely high throughout circulation fluid bed (CFB) gasifier, in which biomass is fully devolitalized with hot sand from a CFB char combustor. The fuel gas can be cooled and cleaned by a conventional scrubbing system. Fuel gas compressor power consumption is reduced 3 to 4 fold verses low Btu biomass gas.

Rohrer, J.W. [Zurn/NEPCO, South Portland, MA (United States); Paisley, M. [Battelle Laboratories, Columbus, OH (United States)

1995-12-31T23:59:59.000Z

390

2.5 CONTINUUM MECHANICS (FLUIDS) Let us consider a fluid medium and use Cartesian tensors to derive the mathematical equations that  

E-Print Network [OSTI]

282 §2.5 CONTINUUM MECHANICS (FLUIDS) Let us consider a fluid medium and use Cartesian tensors to derive the mathematical equations that describe how a fluid behaves. A fluid continuum, like a solid, is the density of the fluid, ij is the stress tensor and bj is an external force per unit mass. In the cgs system

California at Santa Cruz, University of

391

2.5 CONTINUUM MECHANICS (FLUIDS) Let us consider a fluid medium and use Cartesian tensors to derive the mathematical equations that  

E-Print Network [OSTI]

282 §2.5 CONTINUUM MECHANICS (FLUIDS) Let us consider a fluid medium and use Cartesian tensors to derive the mathematical equations that describe how a fluid behaves. A fluid continuum, like a solid , i = 1, 2, 3 is a velocity field, # is the density of the fluid, # ij is the stress tensor and b j

California at Santa Cruz, University of

392

Energy efficiency in the US economy technical report four: Analysis of energy-efficiency investment decisions by small and medium-sized manufacturers  

SciTech Connect (OSTI)

This report highlights the results of a comprehensive analysis of investment decisions regarding energy-efficiency measures at small and medium-sized manufacturing plants. The analysis is based primarily on the experiences of companies participating in the US Department of Energy`s Industrial Assessment Center (IAC) program.

NONE

1996-03-01T23:59:59.000Z

393

JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 102, NO. A10, PAGES 22,221-22,231,OCTOBER 1, 1997 Observations of auroral medium frequency bursts  

E-Print Network [OSTI]

Observations of auroral medium frequency bursts J. LaBelle, S. G. Shepherd,and M. L. Trimpi Department with auroral displays. Although many auroral waves cannot escapethe ionosphereand are only observed with rocket burstistheleastwelldescribed of thesethreephenomena.KelloggandMonson[1979] observed occasional radio bursts at times when

Shepherd, Simon

394

Impact of the In-medium Nucleon-nucleon Cross Section Modification on Early-reaction-phase Dynamics Below 100 A MeV  

SciTech Connect (OSTI)

With a semi-classical transport model studied is the impact of the in-medium NN cross section modifications on the early energy transformation, dynamical emission and quasiprojectile properties of the Ar+Ni and Ni+Ni reactions at 52, 74 and 95(90) A MeV.

Basrak, Z.; Zoric, M. [Ruder Boskovic Institute, Zagreb (Croatia); Eudes, P.; Sebille, F. [Subatech, EMN-IN2P3/CNRS-Universite de Nantes, Nantes (France)

2009-08-26T23:59:59.000Z

395

PROBING THE INTERGALACTIC MEDIUM/GALAXY CONNECTION. V. ON THE ORIGIN OF Ly? AND O VI ABSORPTION AT z < 0.2  

E-Print Network [OSTI]

We analyze the association of galaxies with Ly? and O VI absorption, the most commonly detected transitions of the low-z intergalactic medium (IGM), in the fields of 14 quasars with z[subscript em] = 0.06–0.57. Confirming ...

Prochaska, J. Xavier

396

Medium-solidity Vertical Axis Wind Turbines for use in Urban Environments S. Tullis, A. Fiedler, K. McLaren, S. Ziada  

E-Print Network [OSTI]

Medium-solidity Vertical Axis Wind Turbines for use in Urban Environments S. Tullis, A. Fiedler, K Vertical axis wind turbines are currently experiencing a renewed interest in small- scale applications loadings as the turbine rotates. One technique to reduce vibration is to reduce the turbine rotational

Tullis, Stephen

397

Correlation between medium-range order structure and glass-forming ability for Al-based metallic glasses  

SciTech Connect (OSTI)

To clarify the correlation of medium-range order (MRO) structure with glass forming ability (GFA) of Al-based metallic glasses, Al{sub 86}Ni{sub 14-a}Y{sub a} (a?=?2?9 at.?%) metallic glasses were analyzed by x-ray diffraction in detail and further verified by synchrotron high-energy x-ray diffraction. The prepeak that reflects the MRO structural evolution was found to be much sensitive to alloy composition. We have proposed an icosahedral supercluster MRO structure model in Al-TM (transition metal)-RE (rare earth metal) system, which consists of 12 RE(TM)-centered clusters on the vertex of icosahedral supercluster, one RE(TM)-centered clusters in the center, and TM(RE) atoms located at RE(TM)-centered cluster tetrahedral interstices in the icosahedral supercluster. It was indicated that the MRO structural stability mainly depends on the interaction of efficient dense packing and electrochemical potential equalization principle. The Al{sub 86}Ni{sub 9}Y(La){sub 5} alloys present good GFA due to the combination of the two structural factors.

Wu, N. C. [College of Material and Metallurgy, Northeastern University, Shenyang 110004 (China); Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Yan, M. [Queensland Centre for Advanced Materials Processing and Manufacturing (AMPAM), School of Mechanical and Mining Engineering, The University of Queensland, Brisbane (Australia); Zuo, L. [College of Material and Metallurgy, Northeastern University, Shenyang 110004 (China); Wang, J. Q., E-mail: jqwang@imr.ac.cn [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China)

2014-01-28T23:59:59.000Z

398

The Infrared Medium-Deep Survey II: How to Trigger Radio-AGN? Hints from Their Environments  

E-Print Network [OSTI]

Activity at the centers of galaxies, during which the central supermassive black hole is accreting material, is nowadays accepted to be rather ubiquitous and most probably a phase of every galaxy's evolution. It has been suggested that galactic mergers and interactions may be the culprits behind the triggering of nuclear activity. We use near-infrared data from the new Infrared Medium-Deep Survey (IMS) and the Deep eXtragalactic Survey (DXS) of the VIMOS-SA22 field and radio data at 1.4 GHz from the FIRST survey and a deep VLA survey to study the environments of radio-AGN over an area of ~25 sq. degrees and down to a radio flux limit of 0.1 mJy and a J-band magnitude of 23 mag AB. Radio-AGN are predominantly found in environments similar to those of control galaxies at similar redshift, J-band magnitude, and U-R rest-frame absolute color. However, a sub-population of radio-AGN is found in environments up to 100 times denser than their control sources. We thus preclude merging as the dominant triggering mechan...

Karouzos, Marios; Kim, Jae-Woo; Lee, Seong-Kook; Chapman, Scott; Jeon, Yiseul; Choi, Changsu; Hong, Jueun; Hyun, Minhee; Jun, Hyunsung David; Kim, Dohyeong; Kim, Yongjung; Kim, Ji Hoon; Kim, Duho; Pak, Soojong; Park, Won-Kee; Tak, Yoon Chan; Yoon, Yongmin; Edge, Alastair

2014-01-01T23:59:59.000Z

399

High-pressure late cycle direct injection of natural gas in a rail medium speed diesel engine  

SciTech Connect (OSTI)

The performance of an Electro-Motive Division (EMD) 567B, two-cylinder locomotive research engine, when operated on high-pressure/late-cycle injection of natural gas, is presented in this paper. A redesign and fabrication of the fuel system was undertaken to facilitate the consumption of natural gas. A small percentage of No.2 diesel fuel (DF-2) was used to ignite the natural gas. Engine performance, while running natural gas, resulted in matching rated speed and power with slightly lower thermal efficiency. Full power was achieved with a ratio of 99 percent natural gas and 1 percent diesel fuel. However, at high natural gas to diesel fuel ratios, audible knock was detected. The primary objective of the project was to establish technical feasibility of, and basic technology for, operating medium-speed rail diesel engines on high-pressure natural gas. Secondary objectives were to attain adequate engine performance levels for rail application, develop a system oriented toward retrofit of in-service locomotives, and realize any potential improvements in thermal efficiency due to use of the high-pressure/late-cycle approach.

Wakenell, J.F.; O'Neal, G.B.; Baker, Q.A.

1987-01-01T23:59:59.000Z

400

X-RAY SEARCHES FOR EMISSION FROM THE WHIM IN THE GALACTIC HALO AND THE INTERGALACTIC MEDIUM  

SciTech Connect (OSTI)

At least 50% of the baryons in the local universe are undetected and predicted to be in a hot dilute phase (10{sup 5}-10{sup 7} K) in low and moderate overdensity environments. We searched for the predicted diffuse faint emission through shadowing observations whereby cool foreground gas absorbs more distant diffuse emission. Observations were obtained with Chandra and XMM-Newton. Using the cold gas in two galaxies, NGC 891 and NGC 5907, shadows were not detected and a newer observation of NGC 891 fails to confirm a previously reported X-ray shadow. Our upper limits lie above model predictions. For Local Group studies, we used a cloud in the Magellanic Stream and a compact high-velocity cloud to search for a shadow. Instead of a shadow, the X-ray emission was brighter toward the Magellanic Stream cloud and there is a less significant brightness enhancement toward the other cloud also. The brightness enhancement toward the Magellanic Stream cloud is probably due to an interaction with a hot ambient medium that surrounds the Milky Way. We suggest that this interaction drives a shock into the cloud, heating the gas to X-ray emitting temperatures.

Bregman, Joel N.; Otte, Birgit; Irwin, Jimmy A. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Putman, Mary E. [Department of Astronomy, Columbia University, 550 West 120th Street, Mail Code 5246, New York, NY 10027 (United States); Lloyd-Davies, Edward J. [Astronomy Centre, Department of Physics and Astronomy, School of Science and Technology (SciTech), Pevensey II Building, University of Sussex, Falmer, Brighton, BN1 9QH, England (United Kingdom); Bruens, Christian [Argelander Institut fuer Astronomie, Universitaet Bonn, Bonn (Germany)], E-mail: jbregman@umich.edu, E-mail: otteb@umich.edu, E-mail: jairwin@umich.edu, E-mail: mputman@astro.columbia.edu, E-mail: E.Lloyd-Davies@sussex.ac.uk, E-mail: cbruens@astro.uni-bonn.de

2009-07-10T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

A Harmonic Kicker Scheme for the Circulator Cooler Ring in the Proposed Medium Energy Electron-Ion Collider  

SciTech Connect (OSTI)

The current electron cooler design for the proposed Medium Energy Electron-Ion collider (MEIC) at Jefferson Lab utilizes a circulator ring for reuse of the cooling electron bunch up to 100 times to cool the ion beams. This cooler requires a fast kicker system for injecting and extracting individual bunches in the circulator ring. Such a kicker must work at a high repetition rate, up to 7.5 to 75 MHz depending on the number of turns in the recirculator ring. It also must have a very short rise and fall time (of order of 1 ns) such that it will kick an individual bunch without disturbing the others in the ring. Both requirements are orders of magnitude beyond the present state-of-the-art as well as the goals of other on-going kicker R&D programs such as that for the ILC damping rings. In this paper we report a scheme of creating this fast, high repetition rate kicker by combining RF waveforms at multiple frequencies to create a kicker waveform that will, for example, kick every eleventh bunch while leaving the other ten unperturbed. We also present a possible implementation of this scheme as well as discuss its limitations.

Nissen, Edward W.; Hutton, Andrew M.; Kimber, Andrew J.

2013-06-01T23:59:59.000Z

402

Baryon Cycling in the Low-Redshift Circumgalactic Medium: A Comparison of Simulations to the COS-Halos Survey  

E-Print Network [OSTI]

We analyze the low-redshift (z~0.2) circumgalactic medium by comparing absorption-line data from the COS-Halos Survey to absorption around a matched galaxy sample from two cosmological hydrodynamic simulations. The models include different prescriptions for galactic outflows, namely hybrid energy/momentum driven wind (ezw), and constant winds (cw). We extract for comparison direct observables including equivalent widths, covering factors, ion ratios, and kinematics. Both wind models are generally in good agreement with these observations for HI and certain low ionization metal lines, but show poorer agreement with higher ionization metal lines including SiIII and OVI that are well-observed by COS-Halos. These discrepancies suggest that both wind models predict too much cool, metal-enriched gas and not enough hot gas, and/or that the metals are not sufficiently well-mixed. This may reflect our model assumption of ejecting outflows as cool and unmixing gas. Our ezw simulation includes a heuristic prescription t...

Ford, Amanda Brady; Dave, Romeel; Tumlinson, Jason; Bordoloi, Rongmon; Katz, Neal; Kollmeier, Juna A; Oppenheimer, Benjamin D; Peeples, Molly S; Prochaska, Jason X; Weinberg, David H

2015-01-01T23:59:59.000Z

403

Measurement of the Nucleon Structure Function F2 in the Nuclear Medium and Evaluation of its Moments  

SciTech Connect (OSTI)

We report on the measurement of inclusive electron scattering off a carbon target performed with CLAS at Jefferson Laboratory. A combination of three different beam energies 1.161, 2.261 and 4.461 GeV allowed us to reach an invariant mass of the final-state hadronic system W~2.4 GeV with four-momentum transfers Q2 ranging from 0.2 to 5 GeV2. These data, together with previous measurements of the inclusive electron scattering off proton and deuteron, which cover a similar continuous two-dimensional region of Q2 and Bjorken variable x, permit the study of nuclear modifications of the nucleon structure. By using these, as well as other world data, we evaluated the F2 structure function and its moments. Using an OPE-based twist expansion, we studied the Q2-evolution of the moments, obtaining a separation of the leading-twist and the total higher-twist terms. The carbon-to-deuteron ratio of the leading-twist contributions to the F2 moments exhibits the well known EMC effect, compatible with that discovered previously in x-space. The total higher-twist term in the carbon nucleus appears, although with large systematic uncertainites, to be smaller with respect to the deuteron case for n<7, suggesting partial parton deconfinement in nuclear matter. We speculate that the spatial extension of the nucleon is changed when it is immersed in the nuclear medium.

M. Osipenko

2010-11-01T23:59:59.000Z

404

MHUG process for production of low sulfur and low aromatic diesel fuel. [Medium-pressure Hydro UpGrading  

SciTech Connect (OSTI)

A new hydro-upgrading process operated under medium pressure has been developed to reduce the sulfur and the aromatics content in light cycle oil (LCO). Two catalysts were used in series in this technology. The commercial RN-1 catalyst, which is known as having high activity in hydrodenitrogenation, desulfurization and aromatic saturation, was chosen as the first catalyst. The second one was a nickel-tungsten zeolite catalyst, named RT-5, which was developed by RIPP specially for hydrogenolysis of naphthenic and aromatic hydrocarbons. The pilot plant tests showed that high quality diesel oil with aromatics content less than 20 v% and sulfur content less than 0.05 wt% could be produced from various LCO/straight-run-gas-oil (SRGO) blended feedstocks under hydrogen partial pressure of 6.4 MPa. The reaction temperature and overall space velocity (S.V.) varied in the range of 350--380 C and 0.6--1.2 h[sup [minus]1], respectively, depending on the properties of the feedstocks to be processed and the upgrading depth required. Several examples presented also illustrated that this technology could be used to prepare catalytic reforming feedstock as well, which is in urgent need in China. A life test operated in relatively high severity for 3,000 hr. indicated that the catalysts possessed excellent stability. A commercial demonstration unit has been running well since the last Oct 1.

Shi, Yu Lin; Shi, Jian Wen; Zhang, Xin Wei; Shi, Ya Hua; Li, Da Dong (SINOPEC, Beijing (China). Research Inst. of Petroleum Processing)

1993-01-01T23:59:59.000Z

405

The Structure of the Local Interstellar Medium IV: Dynamics, Morphology, Physical Properties, and Implications of Cloud-Cloud Interactions  

E-Print Network [OSTI]

We present an empirical dynamical model of the local interstellar medium based on 270 radial-velocity measurements for 157 sight lines toward nearby stars. Physical-parameter measurements (i.e., temperature, turbulent velocity, depletions) are available for 90 components, or one-third of the sample, enabling initial characterizations of the physical properties of LISM clouds. The model includes 15 warm clouds located within 15 pc of the Sun, each with a different velocity vector. We derive projected morphologies of all clouds and estimate the volume filling factor of warm partially ionized material in the LISM to be between ~5.5% and 19%. Relative velocities of potentially interacting clouds are often supersonic, consistent with heating, turbulent, and metal-depletion properties. Cloud-cloud collisions may be responsible for the filamentary morphologies found in ~1/3 of LISM clouds, the distribution of clouds along the boundaries of the two nearest clouds (LIC and G), the detailed shape and heating of the Mic Cloud, the location of nearby radio scintillation screens, and the location of a LISM cold cloud. Contrary to previous claims, the Sun appears to be located in the transition zone between the LIC and G Clouds.

Seth Redfield; Jeffrey L. Linsky

2007-09-27T23:59:59.000Z

406

[Medium energy meson research  

SciTech Connect (OSTI)

The activities of this group are primarily concerned with experiments using the Crystal Barrel Detector. This detector is installed and operating at the Low Energy Antiproton Ring (LEAR) at CERN. QCD, the modem theory of the strong interaction, is reasonably well understood at high energies, but unfortunately, low-energy QCD is still not well understood, and is far from being adequately tested. The Crystal Barrel experiments are designed to provide some of the tests. The basic line of research involves meson spectroscopy, analyses bearing on the quark and/or gluon content of nuclear states, and the exploration of mechanisms and rules which govern p[bar p] annihilation dynamics. The Crystal Barrel Detector detects and identifies charged and neutral particles with a geometric acceptance close to 100%. The principal component of the detector is an array of 1,380 CsI(TI) crystals. These crystals surround a Jet Drift Chamber (JDC), located in a 1.5 Tesla magnetic field, which measures the momentum and dE/dx of charged particles. One of the very interesting physics goals of the detector is a search for exotic mesonic states -- glueballs and hybrids. Annihilation at rest will be studied with both liquid and gaseous hydrogen targets. The gaseous target offers the possibility of triggering on atomic L-shell X rays so that specific initial angular momentum states can be studied.These topics as well as other related topics are discussed in this report.

Crowe, K.M.

1992-01-01T23:59:59.000Z

407

[Medium energy meson research  

SciTech Connect (OSTI)

The activities of this group are primarily concerned with experiments using the Crystal Barrel Detector. This detector is installed and operating at the Low Energy Antiproton Ring (LEAR) at CERN. QCD, the modem theory of the strong interaction, is reasonably well understood at high energies, but unfortunately, low-energy QCD is still not well understood, and is far from being adequately tested. The Crystal Barrel experiments are designed to provide some of the tests. The basic line of research involves meson spectroscopy, analyses bearing on the quark and/or gluon content of nuclear states, and the exploration of mechanisms and rules which govern p{bar p} annihilation dynamics. The Crystal Barrel Detector detects and identifies charged and neutral particles with a geometric acceptance close to 100%. The principal component of the detector is an array of 1,380 CsI(TI) crystals. These crystals surround a Jet Drift Chamber (JDC), located in a 1.5 Tesla magnetic field, which measures the momentum and dE/dx of charged particles. One of the very interesting physics goals of the detector is a search for exotic mesonic states -- glueballs and hybrids. Annihilation at rest will be studied with both liquid and gaseous hydrogen targets. The gaseous target offers the possibility of triggering on atomic L-shell X rays so that specific initial angular momentum states can be studied.These topics as well as other related topics are discussed in this report.

Crowe, K.M.

1992-12-01T23:59:59.000Z

408

Effective medium theory  

SciTech Connect (OSTI)

New applications of the theory of homogenization for heterogeneous metamaterials, in particular for acoustic cloaking and for design and engineering of tunable phononic crystal.

Krokhin, Arkadii [Univ. of North Texas, Denton, TX (United States)

2014-04-18T23:59:59.000Z

409

Charmonium in Hot Medium  

E-Print Network [OSTI]

are evaluated. Experimental data on J/[psi] production at CERN-SPS and BNL-RHIC are compared with our numerical results in terms of both rapidity-dependent inclusive yields and transverse momentum (pt) spectra. Within current uncertainties from (interpreting) l...

Zhao, Xingbo

2012-02-14T23:59:59.000Z

410

Comprehensive Compressor Calorimeter Testing of Lower-GWP Alternative Refrigerants for Heat Pump and Medium Temperature Refrigeration Applications  

SciTech Connect (OSTI)

In response to environmental concerns raised by the use of refrigerants with high Global Warming Potential (GWP), the Air-Conditioning, Heating, and Refrigeration Institute (AHRI) has launched an industry-wide cooperative research program, referred to as the Low-GWP Alternative Refrigerants Evaluation Program (AREP), to identify and evaluate promising alternative refrigerants for major product categories. This paper reports one of the Oak Ridge National Laboratory (ORNL) contributions to AREP. It compares performance of alternative refrigerants to that of R-410A and R-404A for heat pump and medium temperature applications, respectively. The alternatives reported in this paper are: R-32, DR-5, and L-41a for R-410A and ARM-31a, D2Y-65, L-40, and a mixture of R-32 and R-134a for R-404A. All performance comparison tests were conducted using scroll compressors of ~1.85 tons (6.5 kW) cooling capacity. Tests were conducted over a range of combinations of saturation suction and saturation discharge temperatures for both compressors. The tests showed that, in general, energy efficiency ratio (EER) and cooling capacity of R-410A alternative refrigerants were slightly lower than that of the baseline refrigerant with a moderate increases in discharge temperature. On the other hand, R-404A alternative refrigerants showed relative performance dependence on saturation suction and saturation discharge temperatures and larger increases in discharge temperature than for the R-410A alternatives. This paper summarizes the relative performance of all alternative refrigerants compared to their respective baseline.

Shrestha, Som S [ORNL] [ORNL; Sharma, Vishaldeep [ORNL] [ORNL; Abdelaziz, Omar [ORNL] [ORNL

2014-01-01T23:59:59.000Z

411

SOLAR RADIATION PRESSURE AND LOCAL INTERSTELLAR MEDIUM FLOW PARAMETERS FROM INTERSTELLAR BOUNDARY EXPLORER LOW ENERGY HYDROGEN MEASUREMENTS  

SciTech Connect (OSTI)

Neutral hydrogen atoms that travel into the heliosphere from the local interstellar medium (LISM) experience strong effects due to charge exchange and radiation pressure from resonant absorption and re-emission of Ly?. The radiation pressure roughly compensates for the solar gravity. As a result, interstellar hydrogen atoms move along trajectories that are quite different than those of heavier interstellar species such as helium and oxygen, which experience relatively weak radiation pressure. Charge exchange leads to the loss of primary neutrals from the LISM and the addition of new secondary neutrals from the heliosheath. IBEX observations show clear effects of radiation pressure in a large longitudinal shift in the peak of interstellar hydrogen compared with that of interstellar helium. Here, we compare results from the Lee et al. interstellar neutral model with IBEX-Lo hydrogen observations to describe the distribution of hydrogen near 1 AU and provide new estimates of the solar radiation pressure. We find over the period analyzed from 2009 to 2011 that radiation pressure divided by the gravitational force (?) has increased slightly from ? = 0.94 ± 0.04 in 2009 to ? = 1.01 ± 0.05 in 2011. We have also derived the speed, temperature, source longitude, and latitude of the neutral H atoms and find that these parameters are roughly consistent with those of interstellar He, particularly when considering the filtration effects that act on H in the outer heliosheath. Thus, our analysis shows that over the period from 2009 to 2011, we observe signatures of neutral H consistent with the primary distribution of atoms from the LISM and a radiation pressure that increases in the early rise of solar activity.

Schwadron, N. A.; Moebius, E.; Kucharek, H.; Lee, M. A.; French, J. [University of New Hampshire, Durham, NH 03824 (United States); Saul, L.; Wurz, P. [University of Bern, 3012 Bern (Switzerland); Bzowski, M. [Space Research Centre of the Polish Academy of Sciences, Warsaw (Poland); Fuselier, S. A.; Livadiotis, G.; McComas, D. J. [Southwest Research Institute, San Antonio, TX 78228 (United States); Frisch, P. [University of Chicago, Chicago, IL 60637 (United States); Gruntman, M. [University of Southern California, Los Angeles, CA 90089 (United States); Mueller, H. R. [Dartmouth College, Hanover, NH 03755 (United States)

2013-10-01T23:59:59.000Z

412

Off-Center Mergers of Clusters of Galaxies and Nonequipartition of Electrons and Ions in Intracluster Medium  

E-Print Network [OSTI]

We investigate the dynamical evolution of clusters of galaxies and their observational consequences during off-center mergers, explicitly considering the relaxation process between ions and electrons in intracluster medium by N-body and hydrodynamical simulations. In the contracting phase a bow shock is formed between the two subclusters. The observed temperature between two peaks in this phase depends on the viewing angle even if the geometry of the system seems to be very simple like head-on collisions. Around the most contracting epoch, when we observe merging clusters nearly along the collision axis, they look like spherical relaxed clusters with large temperature gradients. In the expanding phase, spiral bow shocks occur. As in head-on mergers, the electron temperature is significantly lower than the plasma mean one especially in the post-shock regions in the expanding phase. When the systems have relatively large angular momentum, double-peak structures in the X-ray images can survive even after the most contracting epoch. Morphological features in both X-ray images and electron temperature distribution characteristic to off-center mergers are seriously affected by the viewing angle. When the clusters are observed nearly along the collision axis, the distribution of galaxies' line-of-sight (LOS) velocities is a good indicator of mergers. In the contracting phase, an negative kurtosis and a large skewness are expected for nearly equal mass collisions and rather different mass ones, respectively. To obtain statistically significant results, about 1000 galaxies' LOS velocities are required. For nearby clusters ($z<0.05$), large redshift surveys such as 2dF will enable us to study merger dynamics.

Motokazu Takizawa

1999-10-25T23:59:59.000Z

413

Metallic cobalt and iron particles in large and medium pore zeolites. Methods of generation and ferromagnetic resonance characterization  

SciTech Connect (OSTI)

Spectroscopic studies utilizing photoacoustic electronic spectroscopy, electron paramagnetic resonance, and ferromagnetic resonance have been made on the formation of (1) Co metal particles from CO(NH/sub 3/)/sub 6//sup 3 +/ exchanged into Y zeolite and (2) Fe metal particles from nonframework Fe/sup 3 +/ ions in an aluminoferrisilicate analogue of ZSM-5 zeolite. Decomposition of the Co(NH/sub 3/)/sub 6//sup 3 +/ complex is accompanied by autoreduction to the Co/sup 2 +/ state, observed by EPR at 7/sup 0/K, but no Co metal is formed. The Co/sup 2 +/ ions migrate from the supercage locations of the parent complexes into the hexagonal prisms and are subsequently very difficult to reduce, even with H/sub 2/ at 823/sup 0/K. High-temperature FMR data suggest that the small amount of Co metal particles which are formed exist with the fcc crystal structure yielding g = 2.17 at 508/sup 0/K, consistent with an empirically calculated value for fcc Co. Hexagonal close packed Co particles are expected to exhibit much larger magnetic anisotropy than was observed. The Fe/sup 3 +/ ions in the medium pore pentasil aluminoferrisilicate zeolite can be reduced to the metallic state following either (a) precipitation of the inclusion compound, Fe/sup III/(Fe/sup II/(CN)/sub 5/(NO)), in the zeolite, or (b) generation of superparamagnetic oxidic ferric ion clusters. High-temperature FMR data establish that smaller Fe particles can be obtained by the latter method.

Iton, L.E.; Beal, R.B.; Hamot, P.J.

1983-01-01T23:59:59.000Z

414

Anisotropic MHD Turbulence in the Interstellar Medium and the Sol... http://www.aps.org/meet/DPP02/baps/abs/S120004.html 1 of 1 3/10/05 10:26 AM  

E-Print Network [OSTI]

of Iowa, 203 Van Allen Hall, Iowa City, Iowa 52242) The interstellar medium (ISM) and solar wind-4, Rosen Centre Hotel [BI2.004] Anisotropic MHD Turbulence in the Interstellar Medium and the Solar Wind C energy spectra has been a subject of considerable debate in recent years. In the classic work

Ng, Chung-Sang

415

Charmonium and open charm production in nuclear collisions at SPS/FAIR energies and the possible influence of a hot hadronic medium  

E-Print Network [OSTI]

We provide predictions for charmonium and open charm production in nuclear collisions at SPS/FAIR energies within the framework of the statistical hadronization model. The increasing importance at lower energies of Lambda_c production is demonstrated and provides a challenge for future experiments. We also demonstrate that, because of the large charm quark mass and the different timescales for charm quark and charmed hadron production, possible modifications of charmed hadrons in the hot hadronic medium do not lead to measurable changes in cross sections for D-meson production. A possible influence of medium effects can be seen, however, in yields of charmonium. These effects are visible at all energies and results are presented for the energy range between charm threshold and RHIC energy.

A. Andronic; P. Braun-Munzinger; K. Redlich; J. Stachel

2007-10-26T23:59:59.000Z

416

On the structurization of coal dust precipitations and their influence on aerodynamic resistance by granulated mediums in air filters at nuclear power plants  

E-Print Network [OSTI]

The processes of structurization of dust precipitations in granulated filtering mediums, formed by the monolithic glass spherical granules with the diameters of 2mm and 3mm, are re-searched. The distinctions between the distributions of filtered coal dust masses in the air filters with cylindrical granules and the air filters with spherical granules, are found. The influences by the filtered dust masses on the air resistance of both the air filters with the cylindrical granules and the air filters with the spherical granules are described. The conclusions on a possibility of the use of various chemical adsorbents with different geometric forms and volumetric dimensions to improve the filtering properties of granulated filtering mediums in air filters at nuclear power plants are formulated.

Neklyudov, I M; Fedorova, L I; Poltinin, P Ya

2012-01-01T23:59:59.000Z

417

On the structurization of coal dust precipitations and their influence on aerodynamic resistance by granulated mediums in air filters at nuclear power plants  

E-Print Network [OSTI]

The processes of structurization of dust precipitations in granulated filtering mediums, formed by the monolithic glass spherical granules with the diameters of 2mm and 3mm, are re-searched. The distinctions between the distributions of filtered coal dust masses in the air filters with cylindrical granules and the air filters with spherical granules, are found. The influences by the filtered dust masses on the air resistance of both the air filters with the cylindrical granules and the air filters with the spherical granules are described. The conclusions on a possibility of the use of various chemical adsorbents with different geometric forms and volumetric dimensions to improve the filtering properties of granulated filtering mediums in air filters at nuclear power plants are formulated.

I. M. Neklyudov; O. P. Ledenyov; L. I. Fedorova; P. Ya. Poltinin

2012-07-02T23:59:59.000Z

418

Near-yrast, medium-spin, excited states of {sup 91}Rb, {sup 93}Rb, and {sup 95}Rb  

SciTech Connect (OSTI)

The medium-spin structure of the nuclei {sup 93}Rb and {sup 95}Rb is studied following the neutron-induced fission of {sup 235}U at the PF1B neutron guide, using the FIFI spectrometer, and at the Lohengrin mass spectrometer of the Institut Laue-Langevin Grenoble. These nuclei, plus {sup 91}Rb, are also studied following the spontaneous fission of {sup 248}Cm and {sup 252}Cf sources, using the EUROGAM-II and Gammasphere detector arrays, respectively. A high-spin isomeric state, with a half-life of 111(11) ns, is found in {sup 93}Rb at an excitation energy of 4422.4 keV, which most likely corresponds to the fully aligned [{pi}(g{sub 9/2}) x {nu}(g{sub 7/2}h{sub 11/2})]{sub 27/2}{sup -} configuration. An analogous configuration is proposed for the 5297.9-keV level observed in {sup 91}Rb. A new E3 decay branch of the 1133.9-keV isomer in {sup 91}Rb is found, for which the rather low transition rate of B(E3)=3.8(10) W.u. is determined. The energy of the isomeric state of {sup 95}Rb is now proposed to be at 810.6 keV, with a spin of (9/2{sup +}), and its half-life determined to be T{sub 1/2}=94(7) ns. A cascade of prompt transitions is observed on top of the 810.6-keV isomer in {sup 95}Rb. The near-yrast structures of {sup 91}Rb, {sup 93}Rb, and {sup 95}Rb are compared to the results of shell-model calculations, which support the proposed 27/2{sup -} interpretation of states in {sup 91}Rb and {sup 93}Rb. An analogous 27/2{sup -} state is expected to occur in {sup 95}Rb, as a long-lived isomer at 3.24 MeV. No such isomeric decay could be observed in a measurement using the Lohengrin spectrometer, which shows that, if it exists, its population, following the fission of {sup 235}U, is at least four times lower than that of the analogous 27/2{sup -} isomer in {sup 97}Y.

Simpson, G. S. [LPSC, Universite Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut National Polytechnique de Grenoble, F-38026 Grenoble Cedex (France); Urban, W. [Institut Laue-Langevin, 6 rue J. Horowitz, F-38042 Grenoble (France); Faculty of Physics, University of Warsaw, ul. Hoza 69, PL-00-681 Warsaw (Poland); Sieja, K. [Institute Pluridisciplinaire Hubert Curien, 23 rue du Loess, 67037 Strasbourg Cedex (France); Dare, J. A.; Orlandi, R.; Smith, A. G.; Tsekhanovich, I.; Varley, B. J.; Durell, J. L.; Smith, J. F. [Department of Physics and Astronomy, University of Manchester, M13 9PL Manchester (United Kingdom); Jolie, J.; Linneman, A. [Institut fuer Kernphysik, Universitaet zu Koeln, Zuelpicherstr. 77, D-50937 Koeln (Germany); Scherillo, A. [Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX (United Kingdom); Soldner, T.; Faust, H. [Institut Laue-Langevin, 6 rue J. Horowitz, F-38042 Grenoble (France); Zlomaniec, A.; Rzaca-Urban, T. [Faculty of Physics, University of Warsaw, ul. Hoza 69, PL-00-681 Warsaw (Poland); Ahmad, I.; Greene, J. P. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2010-08-15T23:59:59.000Z

419

Development of a Low NOx Medium sized Industrial Gas Turbine Operating on Hydrogen-Rich Renewable and Opportunity Fuels  

SciTech Connect (OSTI)

This report presents the accomplishments at the completion of the DOE sponsored project (Contract # DE-FC26-09NT05873) undertaken by Solar Turbines Incorporated. The objective of this 54-month project was to develop a low NOx combustion system for a medium sized industrial gas turbine engine operating on Hydrogen-rich renewable and opportunity Fuels. The work in this project was focused on development of a combustion system sized for 15MW Titan 130 gas turbine engine based on design analysis and rig test results. Although detailed engine evaluation of the complete system is required prior to commercial application, those tasks were beyond the scope of this DOE sponsored project. The project tasks were organized in three stages, Stages 2 through 4. In Stage 2 of this project, Solar Turbines Incorporated characterized the low emission capability of current Titan 130 SoLoNOx fuel injector while operating on a matrix of fuel blends with varying Hydrogen concentration. The mapping in this phase was performed on a fuel injector designed for natural gas operation. Favorable test results were obtained in this phase on emissions and operability. However, the resulting fuel supply pressure needed to operate the engine with the lower Wobbe Index opportunity fuels would require additional gas compression, resulting in parasitic load and reduced thermal efficiency. In Stage 3, Solar characterized the pressure loss in the fuel injector and developed modifications to the fuel injection system through detailed network analysis. In this modification, only the fuel delivery flowpath was modified and the air-side of the injector and the premixing passages were not altered. The modified injector was fabricated and tested and verified to produce similar operability and emissions as the Stage 2 results. In parallel, Solar also fabricated a dual fuel capable injector with the same air-side flowpath to improve commercialization potential. This injector was also test verified to produce 15-ppm NOx capability on high Hydrogen fuels. In Stage 4, Solar fabricated a complete set of injectors and a combustor liner to test the system capability in a full-scale atmospheric rig. Extensive high-pressure single injector rig test results show that 15-ppm NOx guarantee is achievable from 50% to 100% Load with fuel blends containing up to 65% Hydrogen. Because of safety limitations in Solar Test Facility, the atmospheric rig tests were limited to methane-based fuel blends. Further work to validate the durability and installed engine capability would require long-term engine field test.

Srinivasan, Ram

2013-07-31T23:59:59.000Z

420

GRB 090510: A DISGUISED SHORT GAMMA-RAY BURST WITH THE HIGHEST LORENTZ FACTOR AND CIRCUMBURST MEDIUM  

SciTech Connect (OSTI)

GRB 090510, observed by both Fermi and AGILE satellites, is the first bright short-hard gamma-ray burst (GRB) with an emission from the keV up to the GeV energy range. Within the Fireshell model, we interpret the faint precursor in the light curve as the emission at the transparency of the expanding e {sup +} e {sup -} plasma: the Proper-GRB. From the observed isotropic energy, we assume a total plasma energy E{sup tot}{sub e{sup +}e{sup -}}=(1.10{+-}0.06) Multiplication-Sign 10{sup 53} erg and derive a Baryon load B = (1.45 {+-} 0.28) Multiplication-Sign 10{sup -3} and a Lorentz factor at transparency {Gamma}{sub tr} = (6.7 {+-} 1.6) Multiplication-Sign 10{sup 2}. The main emission {approx}0.4 s after the initial spike is interpreted as the extended afterglow, due to the interaction of the ultrarelativistic baryons with the CircumBurst Medium (CBM). Using the condition of fully radiative regime, we infer a CBM average spherically symmetric density of (n{sub CBM}) = (1.85 {+-} 0.14) Multiplication-Sign 10{sup 3} particles cm{sup -3}, one of the highest found in the Fireshell model. The value of the filling factor, 1.5 Multiplication-Sign 10{sup -10}{<=}R{<=}3.8 Multiplication-Sign 10{sup -8}, leads to the estimate of filaments with densities n{sub fil} = n{sub CBM}/R approx. (10{sup 6}-10{sup 14}) particles cm{sup -3}. The sub-MeV and the MeV emissions are well reproduced. When compared to the canonical GRBs with (n{sub CBM}) Almost-Equal-To 1 particles cm{sup -3} and to the disguised short GRBs with (n{sub CBM}) Almost-Equal-To 10{sup -3} particles cm{sup -3}, the case of GRB 090510 leads to the existence of a new family of bursts exploding in an overdense galactic region with (n{sub CBM}) Almost-Equal-To 10{sup 3} particles cm{sup -3}. The joint effect of the high {Gamma}{sub tr} and the high density compresses in time and 'inflates' in intensity the extended afterglow, making it appear as a short burst, which we here define as a 'disguised short GRB by excess'. The determination of the above parameter values may represent an important step toward the explanation of the GeV emission.

Muccino, M.; Ruffini, R.; Bianco, C. L.; Izzo, L.; Penacchioni, A. V.; Pisani, G. B. [Dip. di Fisica and ICRA, Sapienza Universita di Roma, Piazzale Aldo Moro 5, I-00185 Rome (Italy)

2013-07-20T23:59:59.000Z

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


421

THE COLUMN DENSITY DISTRIBUTION AND CONTINUUM OPACITY OF THE INTERGALACTIC AND CIRCUMGALACTIC MEDIUM AT REDSHIFT (z) = 2.4  

SciTech Connect (OSTI)

We present new high-precision measurements of the opacity of the intergalactic and circumgalactic medium (IGM; CGM) at (z) = 2.4. Using Voigt profile fits to the full Ly{alpha} and Ly{beta} forests in 15 high-resolution high-S/N spectra of hyperluminous QSOs, we make the first statistically robust measurement of the frequency of absorbers with H I column densities 14{approx}< log (N{sub H{sub I}}/cm{sup -2}){approx}<17.2. We also present the first measurements of the frequency distribution of H I absorbers in the volume surrounding high-z galaxies (the CGM, 300 pkpc), finding that the incidence of absorbers in the CGM is much higher than in the IGM. In agreement with Rudie et al., we find that there are fractionally more high-N{sub H{sub I}} absorbers than low-N{sub H{sub I}} absorbers in the CGM compared to the IGM, leading to a shallower power law fit to the CGM frequency distribution. We use these new measurements to calculate the total opacity of the IGM and CGM to hydrogen-ionizing photons, finding significantly higher opacity than most previous studies, especially from absorbers with log (N{sub H{sub I}}/cm{sup -2}) < 17.2. Reproducing the opacity measured in our data as well as the incidence of absorbers with log (N{sub H{sub I}}/cm{sup -2})>17.2 requires a broken power law parameterization of the frequency distribution with a break near N{sub H{sub I}} Almost-Equal-To 10{sup 15} cm{sup -2}. We compute new estimates of the mean free path ({lambda}{sub mfp}) to hydrogen-ionizing photons at z{sub em} = 2.4, finding {lambda}{sub mfp} = 147 {+-} 15 Mpc when considering only IGM opacity. If instead, we consider photons emanating from a high-z star-forming galaxy and account for the local excess opacity due to the surrounding CGM of the galaxy itself, the mean free path is reduced to {lambda}{sub mfp} = 121 {+-} 15 Mpc. These {lambda}{sub mfp} measurements are smaller than recent estimates and should inform future studies of the metagalactic UV background and of ionizing sources at z Almost-Equal-To 2-3.

Rudie, Gwen C.; Steidel, Charles C. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, MS 249-17, Pasadena, CA 91125 (United States); Shapley, Alice E. [Department of Astronomy, University of California, Los Angeles, 430 Portola Plaza, Los Angeles, CA 90024 (United States); Pettini, Max, E-mail: gwen@astro.caltech.edu [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom)

2013-06-01T23:59:59.000Z

422

Gamma-Ray Burst Afterglows as Probes of Environment and Blastwave Physics II: the Distribution of p and Structure of the Circumburst Medium  

E-Print Network [OSTI]

We constrain blastwave parameters and the circumburst media of a subsample of ten BeppoSAX Gamma-Ray Bursts. For this sample we derive the values of the injected electron energy distribution index, p, and the density structure index of the circumburst medium, k, from simultaneous spectral fits to their X-ray, optical and nIR afterglow data. The spectral fits have been done in count space and include the effects of metallicity, and are compared with the previously reported optical and X-ray temporal behaviour. Using the blastwave model and some assumptions which include on-axis viewing and standard jet structure, constant blastwave energy and no evolution of the microphysical parameters, we find a mean value of p for the sample as a whole of 2.04 +0.02/-0.03. A statistical analysis of the distribution demonstrates that the p values in this sample are inconsistent with a single universal value for p at the 3-sigma level or greater, which has significant implications for particle acceleration models. This approach provides us with a measured distribution of circumburst density structures rather than considering only the cases of k=0 (homogeneous) and k=2 (wind-like). We find five GRBs for which k can be well constrained, and in four of these cases the circumburst medium is clearly wind-like. The fifth source has a value of 0medium.

R. L. C. Starling; A. J. van der Horst; E. Rol; R. A. M. J. Wijers; C. Kouveliotou; K. Wiersema; P. A. Curran; P. Weltevrede

2007-07-28T23:59:59.000Z

423

AN EXPLANATION FOR THE DIFFERENT X-RAY TO OPTICAL COLUMN DENSITIES IN THE ENVIRONMENTS OF GAMMA RAY BURSTS: A PROGENITOR EMBEDDED IN A DENSE MEDIUM  

SciTech Connect (OSTI)

We study the {approx}> 10 ratios in the X-ray to optical column densities inferred from afterglow spectra of gamma ray bursts (GRBs) due to gas surrounding their progenitors. We present time-evolving photoionization calculations for these afterglows and explore different conditions of their environment. We find that homogenous models of the environment (constant density) predict X-ray columns similar to those found in the optical spectra, with the bulk of the opacity being produced by neutral material at large distances from the burst. This result is independent of gas density or metallicity. Only models assuming a progenitor immersed in a dense ({approx}10{sup 2-4} cm{sup -3}) cloud of gas (with radius {approx}10 pc), with a strong, declining gradient of density for the surrounding interstellar medium (ISM) are able to account for the large X-ray to optical column density ratios. However, to avoid an unphysical correlation between the size of this cloud and the size of the ionization front produced by the GRB, the models also require that the circumburst medium is already ionized prior to the burst. The inferred cloud masses are {approx}< 10{sup 6} M{sub Sun }, even if low metallicities in the medium are assumed (Z {approx} 0.1 Z{sub Sun }). These cloud properties are consistent with those found in giant molecular clouds and our results support a scenario in which the progenitors reside within intense star formation regions of galaxies. Finally, we show that modeling over large samples of GRB afterglows may offer strong constraints on the range of properties in these clouds, and the host galaxy ISM.

Krongold, Yair [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-264, 04510 Mexico DF (Mexico); Prochaska, J. Xavier, E-mail: xavier@ucolick.org [Department of Astronomy and Astrophysics, UCO/Lick Observatory, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States)

2013-09-10T23:59:59.000Z

424

THE MULTIWAVELENGTH SURVEY BY YALE-CHILE (MUSYC): DEEP MEDIUM-BAND OPTICAL IMAGING AND HIGH-QUALITY 32-BAND PHOTOMETRIC REDSHIFTS IN THE ECDF-S  

SciTech Connect (OSTI)

We present deep optical 18-medium-band photometry from the Subaru telescope over the {approx}30' x 30' Extended Chandra Deep Field-South, as part of the Multiwavelength Survey by Yale-Chile (MUSYC). This field has a wealth of ground- and space-based ancillary data, and contains the GOODS-South field and the Hubble Ultra Deep Field. We combine the Subaru imaging with existing UBVRIzJHK and Spitzer IRAC images to create a uniform catalog. Detecting sources in the MUSYC 'BVR' image we find {approx}40,000 galaxies with R {sub AB} < 25.3, the median 5{sigma} limit of the 18 medium bands. Photometric redshifts are determined using the EAzY code and compared to {approx}2000 spectroscopic redshifts in this field. The medium-band filters provide very accurate redshifts for the (bright) subset of galaxies with spectroscopic redshifts, particularly at 0.1 < z < 1.2 and at z {approx}> 3.5. For 0.1 < z < 1.2, we find a 1{sigma} scatter in {Delta}z/(1 + z) of 0.007, similar to results obtained with a similar filter set in the COSMOS field. As a demonstration of the data quality, we show that the red sequence and blue cloud can be cleanly identified in rest-frame color-magnitude diagrams at 0.1 < z < 1.2. We find that {approx}20% of the red sequence galaxies show evidence of dust emission at longer rest-frame wavelengths. The reduced images, photometric catalog, and photometric redshifts are provided through the public MUSYC Web site.

Cardamone, Carolin N.; Van Dokkum, Pieter G.; Urry, C. Megan; Brammer, Gabriel [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Taniguchi, Yoshi [Research Center for Space and Cosmic Evolution, Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Gawiser, Eric; Bond, Nicholas [Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854-8019 (United States); Taylor, Edward; Damen, Maaike [Sterrewacht Leiden, Leiden University, NL-2300 RA Leiden (Netherlands); Treister, Ezequiel [Institute for Astronomy, 2680 Woodlawn Drive, University of Hawaii, Honolulu, HI 96822 (United States); Cobb, Bethany E. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Schawinski, Kevin [Yale Center for Astronomy and Astrophysics, Yale University, P.O. Box 208121, New Haven, CT 06520 (United States); Lira, Paulina [Departamento de Astronoma, Universidad de Chile, Casilla 36-D, Santiago (Chile); Murayama, Takashi [Astronomical Institute, Graduate School of Science, Tohoku University, Aramaki, Aoba, Sendai 980-8578 (Japan); Saito, Tomoki [Institute for Physics and Mathematics of the Universe, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Sumikawa, Kentaro, E-mail: carolin.cardamone@astro.yale.ed [Graduate School of Science and Engineering, Ehime University, Bunkyo-cho, Matsuyama 790-8577 (Japan)

2010-08-15T23:59:59.000Z

425

Low Wind Speed Technology Phase II: Investigation of the Application of Medium-Voltage Variable-Speed Drive Technology to Improve the Cost of Energy from Low Wind Speed Turbines; Behnke, Erdman and Whitaker Engineering, Inc.  

SciTech Connect (OSTI)

This fact sheet describes a subcontract with Behnke, Erdman & Whitaker Engineering, Inc. to test the feasibility of applying medium-voltage variable-speed drive technology to low wind speed turbines.

Not Available

2006-03-01T23:59:59.000Z

426

Measurement of the Neutral Current Deep Inelastic Scattering Cross Section at Low and Medium Q{sup 2} Using H1 Data  

SciTech Connect (OSTI)

This report presents the measurements of the inclusive deep inelastic e{sup +}p scattering cross section at low and medium virtuality of the exchanged boson, 0.2medium Q{sup 2}, 12

Picuric, Ivana [Faculty of Natural Sciences and Mathematics, University of Montenegro, P. O. Box 211, 81001 Podgorica (Montenegro)

2010-01-21T23:59:59.000Z

427

Formation of H{sub 3}{sup -} by radiative association of H{sub 2} and H{sup -} in the interstellar medium  

SciTech Connect (OSTI)

We develop the theory of radiative association of an atom and a diatomic molecule within a close-coupling framework. We apply it to the formation of H{sub 3}{sup -} after the low-energy collision (below 0.5 eV) of H{sub 2} with H{sup -}. Using recently obtained potential energy and permanent dipole moment surfaces of H{sub 3}{sup -}, we calculate the lowest rovibrational levels of the H{sub 3}{sup -} electronic ground state and the cross section for the formation of H{sub 3}{sup -} by radiative association between H{sup -} and ortho- and para-H{sub 2}. We discuss the possibility for the H{sub 3}{sup -} ion to be formed and observed in the cold and dense interstellar medium in an environment with a high ionization rate. Such an observation could be a probe for the presence of H{sup -} in the interstellar medium.

Ayouz, M.; Lopes, R.; Raoult, M.; Dulieu, O. [Laboratoire Aime Cotton, CNRS, Bat 505, Universite Paris 11, F-91405 Orsay Cedex (France); Kokoouline, V. [Laboratoire Aime Cotton, CNRS, Bat 505, Universite Paris 11, F-91405 Orsay Cedex (France); Department of Physics, University of Central Florida, Orlando, Florida 32816 (United States)

2011-05-15T23:59:59.000Z

428

Electrocatalytic H2 production with a turnover frequency >107 s?1: The medium provides an increase in rate but not overpotential  

SciTech Connect (OSTI)

Exceptionally fast electrocatalytic H2 production (up to 3 x 107 s -1) at overpotentials of ~400 mV are catalysed by [Ni(PPh2NC6H4X2)2]2+ complexes in an acidic ionic liquid - water medium ([(DMF)H]NTf2-H2O, ?H2O = 0.71). This research was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Office of Basic Energy Sciences and the Office of Science Early Career Research Program through the US DOE, BES (W.J.S.). Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

Hou, Jianbo; Fang, Ming; Cardenas, Allan J.; Shaw, Wendy J.; Helm, Monte L.; Bullock, R. Morris; Roberts, John A.; O'Hagan, Molly J.

2014-11-12T23:59:59.000Z

429

Bulk liquid membrane for the recovery of chromium(VI) from a hydrochloric acid medium using dicyclohexano-18-crown-6 as extractant-carrier  

SciTech Connect (OSTI)

The solvent extraction and transfer of chromic acid from hydrochloric acid medium through a bulk liquid membrane containing dicyclohexano-18-crown-6 (L) were studied. Extraction experiments pointed out that chromium(VI) was coextracted with the chloride ion which formed the complex ion pair L(H{sub 3}O{sup +})CrO{sub 3}Cl{sup {minus}} in the organic phase. The Donnan equilibrium isotherm based on the extraction, stripping, and CrO{sub 3}Cl{sup {minus}} hydrolysis equilibria allowed prediction of the performance of the semipermeable membrane to concentrate chlorochromic acid in the receiving phase. Transport experiments confirmed the ability of the liquid membrane to recover chlorochromic acid in pure water. The transport kinetics was modeled by using the two-film theory applied to the liquid membrane.

Zouhri, A. [Univ. Ibnou Zohr, Agadir (Morocco). Faulte de Sciences] [Univ. Ibnou Zohr, Agadir (Morocco). Faulte de Sciences; Ernst, B.; Burgard, M. [Ecole Europeenne de Chimie, Polymeres et Materiaux, Strasbourg (France)] [Ecole Europeenne de Chimie, Polymeres et Materiaux, Strasbourg (France)

1999-06-01T23:59:59.000Z

430

Measurement of the in-medium K0 inclusive cross section in pi- -induced reactions at 1.15 GeV/c  

E-Print Network [OSTI]

The K0 meson production by pi- mesons of 1.15 GeV/c momentum on C, Al, Cu, Sn and Pb nuclear targets was measured with the FOPI spectrometer at the SIS accelerator of GSI. Inclusive production cross-sections and the momentum distributions of K0 mesons are compared to scaled elementary production cross-sections and to predictions of theoretical models describing the in-medium production of kaons. The data represent a new reference for those models, which are widely used for interpretation of the strangeness-production in heavy-ion collisions. The presented results demonstrate the sensitivity of the kaon production to the reaction amplitudes inside nuclei and point to the existence of a repulsive KN-potential of 20+-5 MeV at normal nuclear matter density.

M. L. Benabderrahmane; N. Herrmann; K. Wisniewski; J. Kecskemeti; A. Andronic; V. Barret; Z. Basrak; N. Bastid; P. Buehler; M. Cargnelli; R. Caplar; E. Cordier; I. Deppner; P. Crochet; P. Dupieux; M. Dzelalija; L. Fabbietti; Z. Fodor; P. Gasik; I. Gasparic; Y. Grishkin; O. N. Hartmann; K. D. Hildenbrand; B. Hong; T. I. Kang; P. Kienle; M. Kirejczyk; Y. J. Kim; M. Kis; P. Koczon; M. Korolija; R. Kotte; A. Lebedev; Y. Leifels; X. Lopez; V. Manko; J. Marton; A. Mangiarotti; M. Merschmeyer; T. Matulewicz; M. Petrovici; K. Piasecki; F. Rami; A. Reischl; W. Reisdorf; M. S. Ryu; P. Schmidt; A. Schuttauf; Z. Seres; B. Sikora; K. S. Sim; V. Simion; K. Siwek-Wilczynska; V. Smolyankin; K. Suzuki; Z. Tyminski; E. Widmann; Z. G. Xiao; T. Yamazaki; I. Yushmanov; X. Y. Zhang; A. Zhilin; J. Zmeskal; E. Bratkovskaya; W. Cassing

2009-03-20T23:59:59.000Z

431

COASTING EXTERNAL SHOCK IN WIND MEDIUM: AN ORIGIN FOR THE X-RAY PLATEAU DECAY COMPONENT IN SWIFT GAMMA-RAY BURST AFTERGLOWS  

SciTech Connect (OSTI)

The plateaus observed in about one half of the early X-ray afterglows are the most puzzling feature in gamma-ray bursts (GRBs) detected by Swift. By analyzing the temporal and spectral indices of a large X-ray plateau sample, we find that 55% can be explained by external, forward shock synchrotron emission produced by a relativistic ejecta coasting in a {rho}{proportional_to}r{sup -2}, wind-like medium; no energy injection into the shock is needed. After the ejecta collects enough medium and transitions to the adiabatic, decelerating blast wave phase, it produces the post-plateau decay. For those bursts consistent with this model, we find an upper limit for the initial Lorentz factor of the ejecta, {Gamma}{sub 0} {<=} 46({epsilon}{sub e}/0.1){sup -0.24}({epsilon}{sub B}/0.01){sup 0.17}; the isotropic equivalent total ejecta energy is E{sub iso} {approx} 10{sup 53}({epsilon}{sub e}/0.1){sup -1.3}({epsilon}{sub B}/0.01){sup -0.09}(t{sub b} /10{sup 4} s) erg, where {epsilon}{sub e} and {epsilon}{sub B} are the fractions of the total energy at the shock downstream that are carried by electrons and the magnetic field, respectively, and t{sub b} is the end of the plateau. Our finding supports Wolf-Rayet stars as the progenitor stars of some GRBs. It raises intriguing questions about the origin of an intermediate-{Gamma}{sub 0} ejecta, which we speculate is connected to the GRB jet emergence from its host star. For the remaining 45% of the sample, the post-plateau decline is too rapid to be explained in the coasting-in-wind model, and energy injection appears to be required.

Shen Rongfeng; Matzner, Christopher D., E-mail: rfshen@astro.utoronto.ca, E-mail: matzner@astro.utoronto.ca [Department of Astronomy and Astrophysics, University of Toronto, Ontario M5S 3H4 (Canada)

2012-01-01T23:59:59.000Z

432

1434 VOLUME 132M O N T H L Y W E A T H E R R E V I E W Ensemble Reforecasting: Improving Medium-Range Forecast Skill Using  

E-Print Network [OSTI]

-Range Forecast Skill Using Retrospective Forecasts THOMAS M. HAMILL University of Colorado and NOAA­CIRES Climate statistics (MOS) approach to improving 6­10-day and week 2 probabilistic forecasts of surface temperature of the NCEP medium-range forecast model with physics operational during 1998. An NCEP­NCAR reanalysis initial

Hamill, Tom

433

ON THE FORMATION OF SILACYCLOPROPENYLIDENE (c-SiC{sub 2}H{sub 2}) AND ITS ROLE IN THE ORGANOSILICON CHEMISTRY IN THE INTERSTELLAR MEDIUM  

SciTech Connect (OSTI)

Organosilicon species such as silicon carbide and silicon dicarbide are considered as key molecular building blocks in the chemical evolution of the interstellar medium and are associated with the formation of silicon-carbide dust grains in the outflow of circumstellar envelopes of carbon-rich asymptotic giant branch (AGB) stars. However, the formation mechanisms of even the simplest silicon-bearing organic molecules have remained elusive for decades. Here, we demonstrate in crossed molecular beam experiments combined with ab initio calculations that the silacyclopropenylidene molecule (c-SiC{sub 2}H{sub 2}) can be synthesized in the gas phase under single-collision conditions via the reaction of the silylidyne radical (SiH) with acetylene (C{sub 2}H{sub 2}). This system denotes the simplest representative of a previously overlooked reaction class, in which the formation of an organosilicon molecule can be initiated via barrierless and exoergic reactions of silylidyne radicals with hydrocarbon molecules in circumstellar envelopes of evolved carbon stars such as IRC+10216. Since organosilicon molecules like silacyclopropenylidene can be eventually photolyzed to carbon-silicon clusters such as silicon dicarbide (c-SiC{sub 2}), silacyclopropenylidene might even represent the missing link between simple molecular precursors and silicon-carbide-rich interstellar grains.

Parker, Dorian S. N.; Wilson, Anthony V.; Kaiser, Ralf I. [Department of Chemistry, University of Hawaii, Honolulu, HI 96822 (United States); Mayhall, Nicholas J.; Head-Gordon, Martin [Department of Chemistry, University of California, Berkeley, CA 94720 (United States); Tielens, Alexander G. G. M. [Leiden Observatory, University of Leiden, Leiden (Netherlands)

2013-06-10T23:59:59.000Z

434

Spatial Variability in the Ratio of Interstellar Atomic Deuterium to Hydrogen. I. Observations toward delta Orionis by the Interstellar Medium Absorption Profile Spectrograph  

E-Print Network [OSTI]

Studies of the abundances of deuterium in different astrophysical sites are of fundamental importance to answering the question about how much deuterium was produced during big bang nucleosynthesis and what fraction of it was destroyed later. With this in mind, we used the Interstellar Medium Absorption Profile Spectrograph (IMAPS) on the ORFEUS-SPAS II mission to observe at a wavelength resolution of 4 km/s (FWHM) the L-delta and L-epsilon absorption features produced by interstellar atomic deuterium in the spectrum of delta Ori A. A chi-square analysis indicated that 0.96 atomic ratio of D to H, we measured the L-alpha absorption features in 57 spectra of delta Ori in the IUE archive. From our measurement of N(H I)= 1.56e20 cm^{-2}, we found that N(D I)/N(H I)= 7.4(+1.9,-1.3)e-6 (90% confidence). Our result for D/H contrasts with the more general finding along other lines of sight that D/H is approximately 1.5e-5. The underabundance of D toward delta Ori A is not accompanied by an overabundance of N or O relative to H, as one might expect if the gas were subjected to more stellar processing than usual.

Edward B. Jenkins; Todd M. Tripp; Przemyslaw R. Wozniak; Ulysses J. Sofia; G. Sonneborn

1999-01-28T23:59:59.000Z

435

On a connection between a class of q-deformed algebras and the Hausdorff derivative in a medium with fractal metric  

E-Print Network [OSTI]

Over the recent decades, diverse formalisms have emerged that are adopted to approach complex systems. Amongst those, we may quote the q-calculus in Tsallis' version of Non-Extensive Statistics with its undeniable success whenever applied to a wide class of different systems; Kaniadakis' approach, based on the compatibility between relativity and thermodynamics; Fractional Calculus (FC), that deals with the dynamics of anomalous transport and other natural phenomena, and also some local versions of FC that claim to be able to study fractal and multifractal spaces and to describe dynamics in these spaces by means of fractional differential equations. The question we might ask is whether or not there are common aspects that connect these alternative approaches. In this short communication, we discuss a possible relationship between q-deformed algebras in two different contexts of Statistical Mechanics, namely, the Tsallis' framework and the Kaniadakis' scenario, with local form of fractional-derivative operators defined in fractal media, the so-called Hausdorff derivatives, mapped into a continuous medium with a fractal measure. This connection opens up new perspectives for theories that satisfactorily describe the dynamics for the transport in media with fractal metrics, such as porous or granular media. Possible connections with other alternative definitions of FC are also contempled. Insights on complexity connected to concepts like coarse-grained space-time and physics in general are pointed out.

J. Weberszpil; Matheus Jatkoske Lazo; J. A. Helayël-Neto

2015-03-04T23:59:59.000Z

436

Gamma-Ray Burst Afterglows as Probes of Environment and Blastwave Physics II: the Distribution of p and Structure of the Circumburst Medium  

E-Print Network [OSTI]

We constrain blastwave parameters and the circumburst media of a subsample of BeppoSAX Gamma-Ray Bursts. For this sample we derive the values of the injected electron energy distribution index, p, and the density structure index of the circumburst medium, k, from simultaneous spectral fits to their X-ray, optical and nIR afterglow data. The spectral fits have been done in count space and include the effects of metallicity, and are compared with the previously reported optical and X-ray temporal behaviour. Assuming the fireball model, we can find a mean value of p for the sample as a whole of 2.04 +0.02/-0.03. A statistical analysis of the distribution demonstrates that the p values in this sample are inconsistent with a single universal value for p at the 3-sigma level or greater, which has significant implications for particle acceleration models. This approach provides us with a measured distribution of circumburst density structures rather than considering only the cases of k=0 (homogeneous) and k=2 (wind-...

Starling, R L C; Rol, E; Wijers, R A M J; Kouveliotou, C; Wiersema, K; Curran, P A; Weltevrede, P

2007-01-01T23:59:59.000Z

437

Selection of Burst-like Transients and Stochastic Variables Using Multi-Band Image Differencing in the Pan-STARRS1 Medium-Deep Survey  

E-Print Network [OSTI]

We present a novel method for the light-curve characterization of Pan-STARRS1 Medium Deep Survey (PS1 MDS) extragalactic sources into stochastic variables (SV) and burst-like (BL) transients, using multi-band image-differencing time-series data. We select detections in difference images associated with galaxy hosts using a star/galaxy catalog extracted from the deep PS1 MDS stacked images, and adopt a maximum a posteriori formulation to model their difference-flux time-series in four Pan-STARRS1 photometric bands g,r,i, and z. We use three deterministic light-curve models to fit burst-like transients and one stochastic light curve model, the Ornstein-Uhlenbeck process, in order to fit variability that is characteristic of active galactic nuclei (AGN). We assess the quality of fit of the models band-wise source-wise, using their estimated leave-out-one cross-validation likelihoods and corrected Akaike information criteria. We then apply a K-means clustering algorithm on these statistics, to determine the sourc...

Kumar, S; Heinis, S; Chornock, R; Berger, E; Rest, A; Huber, M E; Foley, R J; Narayan, G; Marion, G H; Scolnic, D; Soderberg, A; Lawrence, A; Stubbs, C W; Kirshner, R P; Riess, A G; Smartt, S J; Smith, K; Wood-Vasey, W M; Burgett, W S; Chambers, K C; Flewelling, H; Kaiser, N; Metcalfe, N; Price, P A; Tonry, J L; Wainscoat, R J

2015-01-01T23:59:59.000Z

438

Lattice NRQCD study of S- and P-wave bottomonium states in a thermal medium with $N_f=2+1$ light flavors  

E-Print Network [OSTI]

We investigate the properties of S-and P-wave bottomonium states in the vicinity of the deconfinement transition temperature. The light degrees of freedom are represented by dynamical lattice QCD configurations of the HotQCD collaboration with $N_f = 2 + 1$ flavors. Bottomonium correlators are obtained from bottom quark propagators, computed in Non-Relativistic QCD (NRQCD) under the background of these gauge field configurations. The spectral functions for the $^3S_1$ ($\\Upsilon$) and $^3P_1$ ($\\chi_{b1}$) channel are extracted from the Euclidean time correlators using a novel Bayesian approach in the temperature region $140 {\\rm MeV} \\le T \\le 249 {\\rm MeV}$ and the results are contrasted to those from the standard Maximum Entropy Method. We find that the new Bayesian approach is far superior to the Maximum Entropy Method and enables us to study reliably the first peak in the spectral functions even under the limitations present in the finite temperature setup. We find that $\\chi_{b1}$ survives up to $T=249 {\\rm MeV}$, the highest temperature considered in our study and put stringent constraints on the size of the medium modification of $\\Upsilon$ and $\\chi_{b1}$ states.

Seyong Kim; Peter Petreczky; Alexander Rothkopf

2014-09-12T23:59:59.000Z

439

New approach to the generation of metal-bearing, medium-pore, shape-selective zeolites for Fischer-Tropsch catalysis. Spectroscopic studies of zeolites  

SciTech Connect (OSTI)

Two recent developments in zeolite synthesis and modification were successfully combined to demonstrate a new approach to the generation of metal-bearing, medium-pore, shape-selective zeolites for use as catalysts in Fischer-Tropsch conversions. The steps are: (1) synthesis of an aluminoferrisilicate zeolite having the ZSM-5-type structure; (2) removal of the organic base template incorporated in the channel system during synthesis; (3) formation of a polycyano inclusion compound in the AFS zeolite; and (4) reduction of the inclusion compound by hydrogen at approx. 400/sup 0/C. PAS and EPR spectroscopy have been used to establish that the as-synthesized AFS zeolite contains Fe/sup 3 +/ ions in both framework and non-framework sites. FMR spectroscopy has been used to confirm the formation of the metallic (Fe) and bimetallic (Fe/Ru and Fe/Co) particles as products of the reduction of the inclusion compounds by hydrogen. The application of other spectroscopic techniques in recent studies of cations, complexes, and metal particles in zeolites is reviewed: high-resolution solid-state NMR, nuclear-spin-relaxation studies, FMR, EXAFS, and XANES.

Iton, L.E.; Beal, R.B.; Hodul, D.T.

1983-01-01T23:59:59.000Z

440

INVERSE MEDIUM SCATTERING PROBLEMS FOR ...  

E-Print Network [OSTI]

Consider a time-harmonic electromagnetic plane wave incident on a ..... the step size of time marching, whose length is restricted by the stability of the explicit.

SIAM (#1) 1035 2001 Apr 10 12:32:38

2005-08-08T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Programming an Amorphous Computational Medium  

E-Print Network [OSTI]

Amorphous computing considers the problem of controllingmillions of spatially distributed unreliable devices which communicateonly with nearby neighbors. To program such a system, we need a highleveldescription language ...

Beal, Jacob

442

SUPERNOVA REMNANTS AND THE INTERSTELLAR MEDIUM OF M83: IMAGING AND PHOTOMETRY WITH THE WIDE FIELD CAMERA 3 ON THE HUBBLE SPACE TELESCOPE  

SciTech Connect (OSTI)

We present Wide Field Camera 3 images taken with the Hubble Space Telescope within a single field in the southern grand design star-forming galaxy M83. Based on their size, morphology, and photometry in continuum-subtracted Halpha, [S II], Hbeta, [O III], and [O II] filters, we have identified 60 supernova remnant (SNR) candidates, as well as a handful of young ejecta-dominated candidates. A catalog of these remnants, their sizes and, where possible, their Halpha fluxes are given. Radiative ages and pre-shock densities are derived from those SNRs that have good photometry. The ages lie in the range 2.62 < log (tau{sub rad}/yr) < 5.0, and the pre-shock densities at the blast wave range over 0.56 < n{sub 0}/cm{sup -3} < 1680. Two populations of SNRs have been discovered. These divide into a nuclear and spiral arm group and an inter-arm population. We infer an arm to inter-arm density contrast of 4. The surface flux in diffuse X-rays is correlated with the inferred pre-shock density, indicating that the warm interstellar medium (ISM) is pressurized by the hot X-ray plasma. We also find that the ISM in the nuclear region of M83 is characterized by a very high porosity and pressure, and infer an SNR rate of 1 per 70-150 yr for the nuclear (R < 300 pc) region. On the basis of the number of SNRs detected and their radiative ages, we infer that the lower mass of Type II SNe in M83 is M{sub min} = 16{sup +7}{sub -5} M{sub sun}. Finally, we give evidence for the likely detection of the remnant of the historical supernova, SN1968L.

Dopita, Michael A. [Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston Creek, ACT 2611 (Australia); Blair, William P.; Kuntz, Kip D. [Johns Hopkins University, Baltimore, MD (United States); Long, Knox S.; Mutchler, Max; Whitmore, Bradley C.; Bond, Howard E.; MacKenty, John [Space Telescope Science Institute, Baltimore, MD (United States); Balick, Bruce [Department of Astronomy, University of Washington, Seattle, WA 98195-1580 (United States); Calzetti, Daniela [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Carollo, Marcella [Institute of Astronomy, ETH-Zurich, CH-8093 Zurich (Switzerland); Disney, Michael [Department of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA (United Kingdom); Frogel, Jay A. [Association of Universities for Research in Astronomy, Washington, DC 20005 (United States); O'Connell, Robert [Department of Astronomy, University of Virginia, Charlottesville, VA 22904-4325 (United States); Hall, Donald [Institute for Astronomy, Honolulu, HI 96822 (United States); Holtzman, Jon A. [New Mexico State University, Las Cruces, NM 88003 (United States); Kimble, Randy A. [Goddard Space Flight Center, Greenbelt, MD 20771 (United States); McCarthy, Patrick [Carnegie Institute of Washington, Pasadena, CA 91101-1292 (United States); Paresce, Francesco [Institute of Space Astrophysics, INAF, 40129 Bologna (Italy); Saha, Abhijit, E-mail: Michael.Dopita@anu.edu.a [NOAO, Tucson, AZ 85726-6732 (United States)

2010-02-20T23:59:59.000Z

443

Massive stars and the energy balance of the interstellar medium. II. The 35 solar mass star and a solution to the "missing wind problem"  

E-Print Network [OSTI]

We continue our numerical analysis of the morphological and energetic influence of massive stars on their ambient interstellar medium for a 35 solar mass star that evolves from the main sequence through red supergiant and Wolf-Rayet phases, until it ultimately explodes as a supernova. We find that structure formation in the circumstellar gas during the early main-sequence evolution occurs as in the 60 solar mass case but is much less pronounced because of the lower mechanical wind luminosity of the star. Since on the other hand the shell-like structure of the HII region is largely preserved, effects that rely on this symmetry become more important. At the end of the stellar lifetime 1% of the energy released as Lyman continuum radiation and stellar wind has been transferred to the circumstellar gas. From this fraction 10% is kinetic energy of bulk motion, 36% is thermal energy, and the remaining 54% is ionization energy of hydrogen. The sweeping up of the slow red supergiant wind by the fast Wolf-Rayet wind produces remarkable morphological structures and emission signatures, which are compared with existing observations of the Wolf-Rayet bubble S308. Our model reproduces the correct order of magnitude of observed X-ray luminosity, the temperature of the emitting plasma as well as the limb brightening of the intensity profile. This is remarkable, because current analytical and numerical models of Wolf-Rayet bubbles fail to consistently explain these features. A key result is that almost the entire X-ray emission in this stage comes from the shell of red supergiant wind swept up by the shocked Wolf-Rayet wind rather than from the shocked Wolf-Rayet wind itself as hitherto assumed and modeled. This offers a possible solution to what is called the ``missing wind problem'' of Wolf-Rayet bubbles.

Tim Freyer; Gerhard Hensler; Harold W. Yorke

2005-12-05T23:59:59.000Z

444

CLUMPING AND THE INTERPRETATION OF kpc-SCALE MAPS OF THE INTERSTELLAR MEDIUM: SMOOTH H I AND CLUMPY, VARIABLE H{sub 2} SURFACE DENSITY  

SciTech Connect (OSTI)

Many recent models consider the structure of individual interstellar medium (ISM) clouds as a way to explain observations of large parts of galaxies. To compare such models to observations, one must understand how to translate between surface densities observed averaging over large ({approx}kpc) scales and surface densities on the scale of individual clouds ({approx}pc scale), which are treated by models. We define a ''clumping factor'' that captures this translation as the ratio of the mass-weighted surface density, which is often the quantity of physical interest, to the area-weighted surface density, which is observed. We use high spatial resolution (sub-kpc) maps of CO and H I emission from nearby galaxies to measure the clumping factor of both atomic and molecular gas. The molecular and atomic ISM exhibit dramatically different degrees of clumping. As a result, the ratio H{sub 2}/H I measured at {approx}kpc resolution cannot be trivially interpreted as a cloud-scale ratio of surface densities. H I emission appears very smooth, with a clumping factor of only {approx}1.3. Based on the scarce and heterogeneous high-resolution data available, CO emission is far more clumped with a widely variable clumping factor, median {approx}7 for our heterogeneous data. Our measurements do not provide evidence for a universal mass-weighted surface density of molecular gas, but also cannot conclusively rule out such a scenario. We suggest that a more sophisticated treatment of molecular ISM structure, one informed by high spatial resolution CO maps, is needed to link cloud-scale models to kpc-scale observations of galaxies.

Leroy, Adam K. [National Radio Astronomy Observtory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Lee, Cheoljong [Department of Astronomy, University of Virginia, 530 McCormick Road, Charlottesville, VA 22904 (United States); Schruba, Andreas [California Institute for Technology, 1200 E California Blvd, Pasadena, CA 91125 (United States); Bolatto, Alberto [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Hughes, Annie; Sandstrom, Karin; Schinnerer, Eva; Walter, Fabian [Max Planck Institute fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Pety, Jerome [Institut de Radioastronomie Millimetrique, 300 Rue de la Piscine, F-38406 Saint Martin d'Heres (France)

2013-05-20T23:59:59.000Z

445

Method and system for determining depth distribution of radiation-emitting material located in a source medium and radiation detector system for use therein  

DOE Patents [OSTI]

A method, system and a radiation detector system for use therein are provided for determining the depth distribution of radiation-emitting material distributed in a source medium, such as a contaminated field, without the need to take samples, such as extensive soil samples, to determine the depth distribution. The system includes a portable detector assembly with an x-ray or gamma-ray detector having a detector axis for detecting the emitted radiation. The radiation may be naturally-emitted by the material, such as gamma-ray-emitting radionuclides, or emitted when the material is struck by other radiation. The assembly also includes a hollow collimator in which the detector is positioned. The collimator causes the emitted radiation to bend toward the detector as rays parallel to the detector axis of the detector. The collimator may be a hollow cylinder positioned so that its central axis is perpendicular to the upper surface of the large area source when positioned thereon. The collimator allows the detector to angularly sample the emitted radiation over many ranges of polar angles. This is done by forming the collimator as a single adjustable collimator or a set of collimator pieces having various possible configurations when connected together. In any one configuration, the collimator allows the detector to detect only the radiation emitted from a selected range of polar angles measured from the detector axis. Adjustment of the collimator or the detector therein enables the detector to detect radiation emitted from a different range of polar angles. The system further includes a signal processor for processing the signals from the detector wherein signals obtained from different ranges of polar angles are processed together to obtain a reconstruction of the radiation-emitting material as a function of depth, assuming, but not limited to, a spatially-uniform depth distribution of the material within each layer. The detector system includes detectors having different properties (sensitivity, energy resolution) which are combined so that excellent spectral information may be obtained along with good determinations of the radiation field as a function of position.

Benke, Roland R. (Helotes, TX); Kearfott, Kimberlee J. (Ann Arbor, MI); McGregor, Douglas S. (Ann Arbor, MI)

2003-03-04T23:59:59.000Z

446

Medium-Sized Mammals around a Radioactive Liquid Waste Lagoon at Los Alamos National Laboratory: Uptake of Contaminants and Evaluation of Radio-Frequency Identification Technology  

SciTech Connect (OSTI)

Use of a radioactive liquid waste lagoon by medium-sized mammals and levels of tritium, other selected radionuclides, and metals in biological tissues of the animals were documented at Technical Area 53 (TA-53) of Los Alamos National Laboratory during 1997 and 1998. Rock squirrel (Spermophilus variegates), raccoon (Procyon lotor), striped skunk (Mephitis mephitis), and bobcat (Lynx rufus) were captured at TA-53 and at a control site on the Santa Fe National Forest. Captured animals were anesthetized and marked with radio-frequency identification (RFD) tags and/or ear tags. We collected urine and hair samples for tritium and metals (aluminum, antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, and thallium) analyses, respectively. In addition, muscle and bone samples from two rock squirrels collected from each of TA-53, perimeter, and regional background sites were tested for tritium, {sup 137}Cs, {sup 90}Sr, {sup 238}Pu, {sup 239,240}Pu, {sup 241}Am, and total uranium. Animals at TA-53 were monitored entering and leaving the lagoon area using a RFID monitor to read identification numbers from the RFID tags of marked animals and a separate camera system to photograph all animals passing through the monitor. Cottontail rabbit (Sylvilagus spp.), rock squirrel, and raccoon were the species most frequently photographed going through the RFID monitor. Less than half of all marked animals in the lagoon area were detected using the lagoon. Male and female rock squirrels from the lagoon area had significantly higher tritium concentrations compared to rock squirrels from the control area. Metals tested were not significantly higher in rock squirrels from TA-53, although there was a trend toward increased levels of lead in some individuals at TA-53. Muscle and bone samples from squirrels in the lagoon area appeared to have higher levels of tritium, total uranium, and {sup 137}Cs than samples collected from perimeter and background locations. However, the committed effective dose equivalent estimated from the potential human consumption of the muscle and bone tissue from these rock squirrels did not suggest any human health risk. Indirect routes of tritium uptake, possibly through consumption of vegetation, are important for animals in the lagoon area.

Leslie A. Hansen; Phil R. Fresquez; Rhonda J. Robinson; John D. Huchton; Teralene S. Foxx

1999-11-01T23:59:59.000Z

447

LOCAL LYMAN BREAK GALAXY ANALOGS: THE IMPACT OF MASSIVE STAR-FORMING CLUMPS ON THE INTERSTELLAR MEDIUM AND THE GLOBAL STRUCTURE OF YOUNG, FORMING GALAXIES  

SciTech Connect (OSTI)

We report on the results of Hubble Space Telescope optical and UV imaging, Spitzer mid-IR photometry, and optical spectroscopy of a sample of 30 low-redshift (z approx 0.1 to 0.3) galaxies chosen from the Sloan Digital Sky Survey and Galaxy Evolution Explorer surveys to be accurate local analogs of the high-redshift Lyman break galaxies. The Lyman break analogs (LBAs) are similar in stellar mass, metallicity, dust extinction, star formation rate (SFR), physical size, and gas velocity dispersion, thus enabling a detailed investigation of many processes that are important in star-forming galaxies at high redshift. The main optical emission-line properties of LBAs, including evidence for outflows, are also similar to those typically found at high redshift. This indicates that the conditions in their interstellar medium are comparable. In the UV, LBAs are characterized by complexes of massive clumps of star formation, while in the optical they most often show evidence for (post-)mergers and interactions. In six cases, we find a single extremely massive (up to several x10{sup 9} M{sub sun}) compact (radius approx10{sup 2} pc) dominant central object (DCO). The DCOs are preferentially found in LBAs with the highest mid-IR luminosities (L{sub 24m}u{sub m} = 10{sup 10.3}-10{sup 11.2} L{sub sun}) and correspondingly high SFRs (15-100 M{sub sun} yr{sup -1}). We show that the massive star-forming clumps (including the DCOs) have masses much larger than the nuclear super star clusters seen in normal late-type galaxies. However, the DCOs do have masses, sizes, and densities similar to the excess light/central cusps seen in typical elliptical galaxies with masses similar to the LBA galaxies. We suggest that the DCOs form in the present-day examples of the dissipative mergers at high redshift that are believed to have produced the central cusps in local ellipticals (consistent with the disturbed optical morphologies of the LBAs). More generally, the properties of the LBAs are consistent with the idea that instabilities in a gas-rich disk lead to very massive star-forming clumps that eventually coalesce to form a spheroid. Finally, we comment on the apparent lack of energetically significant active galactic nuclei in the DCOs. We speculate that the DCOs are too young at present to grow a supermassive black hole because they are still in a supernova-dominated outflow phase (age less than 50 Myr).

Overzier, Roderik A. [Max-Planck-Institut for Astrophysics, D-85748 Garching (Germany); Heckman, Timothy M.; Ptak, Andy; Ford, Holland C. [Department of Physics and Astronomy, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Tremonti, Christy [Max-Planck Institute for Astronomy, Koenigstuhl 17, D-69117, Heidelberg (Germany); Armus, Lee [Spitzer Science Center, California Institute of Technology, Pasadena, CA (United States); Basu-Zych, Antara [NASA Goddard Space Flight Center, Laboratory for X-ray Astrophysics, Greenbelt, MD 20771 (United States); Goncalves, Thiago; Martin, D. Christopher [California Institute of Technology, MC 405-47, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Rich, R. Michael [Deptartment of Physics and Astronomy, Division of Astronomy and Astrophysics, University of California, Los Angeles, CA 90095-1562 (United States); Schiminovich, David [Department of Astronomy, Columbia University, MC 2457, 550 West 120th Street, New York, NY 10027 (United States); Madore, Barry; Seibert, Mark, E-mail: overzier@mpa-garching.mpg.d [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)

2009-11-20T23:59:59.000Z

448

Effects of in-medium cross sections and optical potential on thermal-source formation in p+{sup 197}Au reactions at 6.2-14.6 GeV/c  

SciTech Connect (OSTI)

Effects of in-medium cross sections and of optical potential on preequilibrium emission and on formation of a thermal source are investigated by comparing the results of transport simulations with experimental results from the p+{sup 197}Au reaction at 6.2-14.6 GeV/c. The employed transport model includes light-composite-particle production and allows for inclusion of in-medium particle-particle cross-section reduction and of momentum dependence in the particle optical potentials. Compared to the past, the model incorporates improved parametrizations of elementary high-energy processes. The simulations indicate that the majority of energy deposition occurs during the first 25 fm/c of a reaction. This is followed by a preequilibrium emission and readjustment of system density and momentum distribution toward an equilibrated system. Within different variants of calculations, the best agreement with data, on the d/p and t/p yield ratios and on the residue mass and charge numbers, is obtained at the time of about 65 fm/c from the start of a reaction, for simulations employing reduced in-medium cross sections and momentum-dependent optical potentials. By that time, the preequilibrium nucleon and cluster emission, as well as mean field readjustments, drive the system to a state of depleted average density, {rho}/{rho}{sub 0}{approx}1/4-1/3 for central collisions, and low-to-moderate excitation, i.e., the region of nuclear liquid-gas phase transition.

Turbide, S. [Departement de Physique, de Genie Physique et d'Optique, Universite Laval, Quebec, G1K 7P4 (Canada); Department of Physics, McGill University, 3600 University Street, Montreal, H3A 2T8 (Canada); Beaulieu, L.; Roy, R. [Departement de Physique, de Genie Physique et d'Optique, Universite Laval, Quebec, G1K 7P4 (Canada); Danielewicz, P.; Huang, R.; Lynch, W.G.; Tsang, M.B.; Xi, H. [Department of Physics and NSCL, Michigan State University, East Lansing, Michigan 48824 (United States); Viola, V.E.; Kwiatkowski, K.; Hsi, W.-C.; Wang, G.; Lefort, T.; Bracken, D.S.; Cornell, E.; Ginger, D.S. [Department of Chemistry and IUCF, Indiana University, Bloomington, Indiana 47405 (United States); Breuer, H. [Department of Physics, University of Maryland, College Park, Maryland 20740 (United States); Gimeno-Nogues, F.; Ramakrishnan, E.; Rowland, D. [Department of Chemistry and Cyclotron Institute, Texas A and M University, College Station, Texas 77843 (United States)] [and others

2004-07-01T23:59:59.000Z

449

Suppression pattern of neutral pions at high transverse momentum in Au+Au collisions at sqrt(s_NN) = 200 GeV and constraints on medium transport coefficients  

E-Print Network [OSTI]

For Au + Au collisions at 200 GeV we measure neutral pion production with good statistics for transverse momentum, p_T, up to 20 GeV/c. A fivefold suppression is found, which is essentially constant for 5 transport coefficient of the medium, e.g. \\mean(q^hat) in the parton quenching model. The spectral shape is similar for all collision classes, and the suppression does not saturate in Au+Au collisions; instead, it increases proportional to the number of participating nucleons, as N_part^2/3.

PHENIX Collaboration; A. Adare

2008-01-25T23:59:59.000Z

450

2.3-MW Medium-Voltage, Three-Level Wind Energy Inverter Applying a Unique Bus Structure and 4.5-kV Si/SiC Hybrid Isolated Power Modules: Preprint  

SciTech Connect (OSTI)

A high-efficiency, 2.3-MW, medium-voltage, three-level inverter utilizing 4.5-kV Si/SiC (silicon carbide) hybrid modules for wind energy applications is discussed. The inverter addresses recent trends in siting the inverter within the base of multimegawatt turbine towers. A simplified split, three-layer laminated bus structure that maintains low parasitic inductances is introduced along with a low-voltage, high-current test method for determining these inductances. Feed-thru bushings, edge fill methods, and other design features of the laminated bus structure provide voltage isolation that is consistent with the 10.4-kV module isolation levels. Inverter efficiency improvement is a result of the (essential) elimination of the reverse recovery charge present in 4.5-kV Si PIN diodes, which can produce a significant reduction in diode turn-off losses as well as insulated-gate bipolar transistor (IGBT) turn-on losses. The hybrid modules are supplied in industry-standard 140 mm x 130 mm and 190 mm x 130 mm packages to demonstrate direct module substitution into existing inverter designs. A focus on laminated bus/capacitor-bank/module subassembly level switching performance is presented.

Erdman, W.; Keller, J.; Grider, D.; VanBrunt, E.

2014-11-01T23:59:59.000Z

451

Low Wind Speed Turbine Project Phase II: The Application of Medium-Voltage Electrical Apparatus to the Class of Variable Speed Multi-Megawatt Low Wind Speed Turbines; 15 June 2004--30 April 2005  

SciTech Connect (OSTI)

Kilowatt ratings of modern wind turbines have progressed rapidly from 50 kW to 1,800 kW over the past 25 years, with 3.0- to 7.5-MW turbines expected in the next 5 years. The premise of this study is simple: The rapid growth of wind turbine power ratings and the corresponding growth in turbine electrical generation systems and associated controls are quickly making low-voltage (LV) electrical design approaches cost-ineffective. This report provides design detail and compares the cost of energy (COE) between commercial LV-class wind power machines and emerging medium-voltage (MV)-class multi-megawatt wind technology. The key finding is that a 2.5% reduction in the COE can be achieved by moving from LV to MV systems. This is a conservative estimate, with a 3% to 3.5% reduction believed to be attainable once purchase orders to support a 250-turbine/year production level are placed. This evaluation considers capital costs as well as installation, maintenance, and training requirements for wind turbine maintenance personnel. Subsystems investigated include the generator, pendant cables, variable-speed converter, and padmount transformer with switchgear. Both current-source and voltage-source converter/inverter MV topologies are compared against their low-voltage, voltage-source counterparts at the 3.0-, 5.0-, and 7.5-MW levels.

Erdman, W.; Behnke, M.

2005-11-01T23:59:59.000Z

452

Medium and Heavy Duty Vehicle Field Evaluations  

Broader source: Energy.gov [DOE]

2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

453

Variable horizon in a peridynamic medium.  

SciTech Connect (OSTI)

A notion of material homogeneity is proposed for peridynamic bodies with vari- able horizon but constant bulk properties. A relation is derived that scales the force state according to the position-dependent horizon while keeping the bulk properties un- changed. Using this scaling relation, if the horizon depends on position, artifacts called ghost forces may arise in a body under homogeneous deformation. These artifacts de- pend on the second derivative of horizon and can be reduced by use of a modified equilibrium equation using a new quantity called the partial stress . Bodies with piece- wise constant horizon can be modeled without ghost forces by using a technique called a splice between the regions. As a limiting case of zero horizon, both partial stress and splice techniques can be used to achieve local-nonlocal coupling. Computational examples, including dynamic fracture in a one-dimensional model with local-nonlocal coupling, illustrate the methods.

Silling, Stewart A.; Littlewood, David John; Seleson, Pablo

2014-10-01T23:59:59.000Z

454

Archived Reference Building Type: Medium office  

Broader source: Energy.gov [DOE]

Here you will find past versions of the commercial reference building models for existing buildings constructed in or after 1980, organized by building type and location. A summary of building types and climate zones is available for reference. Current versions are also available.

455

Archived Reference Building Type: Medium office  

Broader source: Energy.gov [DOE]

Here you will find past versions of the commercial reference building models for existing buildings constructed before 1980, organized by building type and location. A summary ofbuilding types and climate zones is available for reference. Current versions are also available.

456

The reemergence of medium scale gasifications technology  

SciTech Connect (OSTI)

Gasification of solid material is a well proven field, but the introduction of abundant and cheap petroleum fuels after WW II caused the technology to be neglected. There are three types of reactors: the fixed fuel bed, the fluidized bed, and the entrained fuel reactor. The advantages, but more to the point, the drawbacks of each system are reviewed. In order for gasification to fill modern industrial needs the advantages of the three types must be combined without their drawbacks. A reactor needs to be tar-free, have a high volume gas output relative to reactor size, accept a wide range of fuels, and have a comparable Btu production level of fuel gas. These specifications are met by the Series 8000 gas generator manufactured by Enerdyne Corporation.

Reindl, W.J.

1982-06-01T23:59:59.000Z

457

Recent Studies on Inverse Medium Scattering Problems  

E-Print Network [OSTI]

Numerical examples are presented to illustrate the efficiency and robustness of the ... Energy estimates for the scattered field are established, which provide ...

2007-06-28T23:59:59.000Z

458

Construction of spectral functions for medium nuclei  

E-Print Network [OSTI]

This article is aimed at improving the description of lepton-nucleus interactions in the sub-GeV energy range. Approximate spectral functions for oxygen, calcium, and argon are constructed and used to obtain the electron cross sections in a given scattering angle. Comparison with a sample of available experimental data shows satisfactory agreement. Discrepancy between the presented model and the systematic computations available for oxygen [O. Benhar et al., Phys. Rev. D 72, 053005 (2005)] is also found to be very small. Analysis of appropriate kinematical regions leads to the conclusion that the obtained argon spectral function should describe well neutrino scattering in the 800-MeV energy region. Several approximations used in the model are critically reviewed. All the details needed to implement the presented approach in Monte Carlo simulations are given.

Artur M. Ankowski; Jan T. Sobczyk

2008-04-16T23:59:59.000Z

459

Medium Effects on the Rho-Meson  

E-Print Network [OSTI]

The property of a rho meson in dense nuclear matter is studied using the QCD sum rule. The spectral function appearing on the hadronic side of the sum rule is evaluated in the vector dominance model that takes into account the interaction between...

Asakawa, M.; Ko, Che Ming.

1993-01-01T23:59:59.000Z

460

Medium dependence of asphaltene agglomeration inhibitor efficiency  

E-Print Network [OSTI]

Applying chemical additives (molecule inhibitors or dispersants) is one of the common ways to control asphaltene agglomeration and precipitation. However, it is not clear why at some conditions the synthetic flocculation inhibitors as well as resins not only do not inhibit the asphaltene agglomeration,, they may also promote it, and why the increasing of the additive concentration may lead to the diminishing of their efficacy. To clarify this issue, in the present work we have performed a set of vapor preassure osmometry experiments investigating the asphaltene agglomeration inhibition by commercial and new inhibitor molecules in toluene and o-diclorobenzene. Monte Carlo computer modeling has been applied to interpret some unexpected trends of molar mass of the Puerto Ceiba asphaltene clusters at different concentrations of inhibitor, assuming that inhibitors efficiency is directly related to their adsorption on the surface of asphaltene or its complexes. It has been found that a self-assembly of inhibitor molecules, induced by relative lyophilic or lyophobic interactions, may be a reason of the inhibitor efficacy declining.

Mariana Barcenas; Pedro Orea; Eduardo Buenrostro-Gonzalez; Luis S. Zamudio-Rivera; Yurko Duda

2007-10-05T23:59:59.000Z

Note: This page contains sample records for the topic "medium medium medium" 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

Category:MediumOffice | Open Energy Information  

Open Energy Info (EERE)

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: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating SolarElectricEnergyCTBarreis aCallahanWind FarmAdd a

462

The influence of ambient medium density on laser ablation processes  

SciTech Connect (OSTI)

Interest in high flux transport processes has grown in recent years along with the ability and need to manipulate systems with microscopic length and time scales. These systems present unique engineering challenges. Because the time and length scales associated with these problems are very small, assumptions of local equilibrium, physical and mathematical smoothness of boundaries and the unambiguous definition of thermodynamic fields can not be automatically made, even though they may ultimately be acceptable. Furthermore, the observations are made on macroscopic or integrated scales. The large difference in scales between the temporal evolution of the process and the observation requires careful consideration of the claims made regarding the system`s microscopic, temporal behavior. In particular, consistency of a proposed model with observed results does not guarantee uniqueness, or predictive accuracy for the model. For these reasons, microscale heat transfer systems demand a careful consideration of the framework within which the experimentation and analysis are conducted.

Kilgo, M.M. III

1995-11-01T23:59:59.000Z

463

Medium-spin structure of {sup 145}Cs  

SciTech Connect (OSTI)

Excited states in {sup 145}Cs, populated following the spontaneous fission of {sup 248}Cm, were studied by means of prompt-gamma spectroscopy, using the EUROGAM2 multidetector array. A new level scheme of {sup 145}Cs was proposed. We identified a decoupled band corresponding to 1/2[550] proton configuration and interpreted the ground-state band as a mixed configuration of 1/2[440] and 3/2[422] proton orbitals. Quasiparticle-rotor calculations performed for {sup 145}Cs support such assignments. The electric dipole moment in {sup 145}Cs, D{sub 0}=0.013(4) efm, is smaller than in lighter Cs isotopes, which suggests that octupole correlations in Cs isotopes decrease at the neutron number N=90, similarly as observed in the {sup 146}Ba and {sup 147}La isotones.

Rzaca-Urban, T. [Faculty of Physics, University of Warsaw, ul. Hoza 69, PL-00681 Warsaw (Poland); Urban, W. [Faculty of Physics, University of Warsaw, ul. Hoza 69, PL-00681 Warsaw (Poland); Institut Laue-Langevin, 6 rue J. Horowitz, F-38042 Grenoble (France); Pinston, J. A.; Simpson, G. S. [Laboratoire de Physique Subatomique et de Cosmologie, Universite Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut National Polytechnique de Grenoble, F-38026 Grenoble Cedex (France); Durell, J. L.; Smith, A. G. [Department of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Ahmad, I. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2010-07-15T23:59:59.000Z

464

SPECTROSCOPY OF ELECTROPRODUCED LIGHT TO MEDIUM MASS LAMBDA HYPERNUCLEI  

SciTech Connect (OSTI)

One of the main tasks of nuclear physics is the study of subatomic particles and their interactions. Nowadays, the fundamental theory of strong interactions is a particularly interesting subject in the field. At the current moment, such a theory is not complete yet. It describes very well the nucleon-nucleon (NN) interactions, which were intensively studied over the last several decades. In our modern, technically advanced world the research gravitates towards the higher energies, reaching deeper inside of the nuclear structure. About sixty years ago the strong interaction was associated with the interaction between nucleons responsible for holding those nucleons together within the nuclear volume. However, with discovery of mesons and strange particles, the picture has changed. The proof of bound states of strange baryons (? particles) with nucleons revealed a broad class of particles participating in the strong interaction, called hadrons. The rich variety of hadron interactions raises an important topic in modern nuclear physics which strives for providing a deep insight into nuclear matter structure. The analysis of the interaction of a strange baryon, called a hyperon, with a nucleon delivers new knowledge of nuclear properties, which were not understood with widely studied nucleon-nucleon interactions. The direct approach for creating an interaction of free hyperons with nucleons in the target is not an easy task in experimental nuclear physics. The relatively short lifetime of free hyperons, which can only be produced as a secondary beam, leads to extremely low statistics. Nowadays, the best known method of hyperon-nucleon interaction study is the formation of hyperons inside of the nucleus. The bound hyperon serves as a probe of nuclear properties of such complex nuclear systems called hypernuclei. Hypernuclear physics itself is a sub-area of nuclear physics, which studies such bound systems. It employs the rich knowledge of the nucleon-nucleon interaction and at the same time performs a generalization of the above mentioned interaction for systems with a third quark flavor – strangeness [1]. Production reactions of ? particles and hypernuclei, as well as spectroscopy and decay modes, provide valuable information on the hyperon interaction. For example, analysis of ? and hypernuclear decay modes gives knowledge of the properties of weak interactions. The study of the energy of ground and excited states exposes the laws of baryon distribution inside of the nucleus. Investigation of ?N and ?? potentials is important for baryon-baryon theories that include strange quarks, e.g. SU(3). These potentials are more short-ranged than the ones for NN and therefore the additional degrees of freedom play an essential role.

Pavlo Baturin

2010-07-13T23:59:59.000Z

465

Bibliographic survey of medium energy inclusive reaction data  

SciTech Connect (OSTI)

A bibliographic survey of inclusive reaction data (experimental and theoretical) for several projectile types having energies between 50 and 1000 MeV has been completed. Approximately one thousand references selected from this survey describe the current state of knowledge for particle-induced inclusive reaction data. The search covered data for the following projectiles: p, d, t, /sup 3/He, /sup 4/He, and lithium ions.

Arthur, E.D.; Madland, D.G.; McC