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1

Mathematical modeling of heterogeneous detonation in gas suspensions of aluminum and coal-dust particles  

SciTech Connect

Results of investigations performed by the authors in the field of theoretical and numerical modeling of heterogeneous detonation of reacting gas suspensions since 2005 are systematized.

Fedorov, A.V.; Fomin, V.M.; Khmel, T.A. [Russian Academy of Sciences, Novosibirsk (Russian Federation)

2009-07-15T23:59:59.000Z

2

Dust particles in mean motion resonances influenced by an interstellar gas flow  

Science Journals Connector (OSTI)

......ascending node. The sums in equations (16)-(20) run over all particle species i in the IGF. is the ratio of solar wind energy to electromagnetic solar energy, both radiated per unit of time Here, u is the speed of the solar wind with respect......

P. Pástor

2013-01-01T23:59:59.000Z

3

Airborne Particles in Outdoor Air: Atmospheric Dust  

Science Journals Connector (OSTI)

For industrial products, in addition to the harmful effect like usual particles, the particular harmful effect of atmospheric dust especially metal particles is very large. For example, the light metal element...

Zhonglin Xu

2014-01-01T23:59:59.000Z

4

Dust-regulated galaxy formation and evolution:A new chemodynamical model with live dust particles  

E-Print Network (OSTI)

Interstellar dust plays decisive roles in the conversion of neutral to molecular hydrogen (H_2), the thermodynamical evolution of interstellar medium (ISM), and the modification of spectral energy distributions (SEDs) of galaxies. These important roles of dust have not been self-consistently included in previous numerical simulations of galaxy formation and evolution. We have therefore developed a new model by which one can investigate whether and how galaxy formation and evolution can be influenced by dust-related physical processes such as photo-electric heating, H_2 formation on dust, and stellar radiation pressure on dust in detail. A novel point of the model is that different dust species in a galaxy are represented by `live dust' particles (i.e., not test particles). Therefore, dust particles in a galaxy not only interact gravitationally with all four components of the galaxy (i.e., dark matter, stars, gas, and dust) but also are grown and destroyed through physical processes of ISM. First we describe a...

Bekki, Kenji

2015-01-01T23:59:59.000Z

5

Characterization of jovian plasma embedded dust particles  

E-Print Network (OSTI)

As the data from space missions and laboratories improve, a research domain combining plasmas and charged dust is gaining in prominence. Our solar system provides many natural laboratories such as planetary rings, comet comae and tails, ejecta clouds around moons and asteroids, and Earth's noctilucent clouds for which to closely study plasma-embedded cosmic dust. One natural laboratory to study electromagnetically-controlled cosmic dust has been provided by the Jovian dust streams and the data from the instruments which were on board the Galileo spacecraft. Given the prodigious quantity of dust poured into the Jovian magnetosphere by Io and its volcanoes resulting in the dust streams, the possibility of dusty plasma conditions exist. This paper characterizes the main parameters for those interested in studying dust embedded in a plasma with a focus on the Jupiter environment. I show how to distinguish between dust-in-plasma and dusty-plasma and how the Havnes parameter P can be used to support or negate the possibility of collective behavior of the dusty plasma. The result of applying these tools to the Jovian dust streams reveals mostly dust-in-plasma behavior. In the orbits displaying the highest dust stream fluxes, portions of orbits E4, G7, G8, C21 satisfy the minimum requirements for a dusty plasma. However, the P parameter demonstrates that these mild dusty plasma conditions do not lead to collective behavior of the dust stream particles.

Amara L. Graps

2006-05-21T23:59:59.000Z

6

Characterisation of Dust Particles Trapped in Silica Aerogels.  

E-Print Network (OSTI)

?? This thesis involves the study of dust particles trapped in silica aerogel for fusion dust diagnostics purpose. The low velocity impact experiments are done… (more)

Liu, Bing

2011-01-01T23:59:59.000Z

7

The gas temperature in circumstellar disks: effects of dust settling  

E-Print Network (OSTI)

The gas temperature in circumstellar disks: effects of dust settling F. Faas, G.J. van Zadelhoff, E distributions. The disk gas-temperature (T ¢¡¢£ ) is in general assumed to be equal to the dust-temperature (T¤¦¥ £ § ), due to collisions. Dust settling depends on both the gas and dust temperature. T

Zadelhoff, Gerd-Jan van

8

Dust-Gas Interrelations In Comets: Observations And Theory  

Science Journals Connector (OSTI)

Comet Hale-Bopp (C/1995 O1) was discovered ... comet, in the sense of release of gas and dust in modern times. This has ... of important issues regarding interrelations between dust and gas in comets, a descripti...

Michael R. Combi; KONSTANTIN KABIN; Darren L. DeZEEUW…

9

Modelling Gas And Dust Release From Comet Hale–Bopp  

Science Journals Connector (OSTI)

Numerical simulations of the evolving activity of comet Hale-Bopp are presented, assuming a porous, ... km in radius, made of dust and gas-laden amorphous ice. The main effects included ... crystallization of amo...

D. Prialnik

10

Surface States and the Charge of a Dust Particle in a Plasma  

SciTech Connect

We investigate electron and ion surface states of a negatively charged dust particle in a gas discharge and identify the charge of the particle with the electron surface density bound in the polarization-induced short-range part of the particle potential. On that scale, ions do not affect the charge. They are trapped in the shallow states of the Coulomb tail of the potential and act only as screening charges. Using orbital-motion limited electron charging fluxes and the particle temperature as an adjustable parameter, we obtain excellent agreement with experimental data.

Bronold, F. X.; Fehske, H.; Deutsch, H. [Institut fuer Physik, Ernst-Moritz-Arndt-Universitaet Greifswald, D-17489 Greifswald (Germany); Kersten, H. [Institut fuer Experimentelle und Angewandte Physik, Christian-Albrechts-Universitaet zu Kiel, D-24098 Kiel (Germany)

2008-10-24T23:59:59.000Z

11

Temperature-influenced dynamics of small dust particles  

Science Journals Connector (OSTI)

......e.g. Sun for the case...its internal distribution in the particle...vary with its temperature. The largest...distance from the Sun is followed...depend on temperature. Consequently...the complex distribution of dust material...characterized by temperature-dependent...distance to the Sun (i.e......

M. Kocifaj; J. Klacka; H. Horvath

2006-08-21T23:59:59.000Z

12

Upper limit on the gas density in the Beta-Pictoris system: On the effect of gas drag on the dust dynamics  

E-Print Network (OSTI)

We investigate in this paper the effect of gas drag on the dynamics of the dust particles in the edge-on Beta-Pictoris disc in order to derive an upper limit on the mass of gas in this system. Our study is motivated by the large uncertainties on the amount of gas in the Beta-Pictoris disc currently found in the literature. The dust particles are assumed to originate from a colliding annulus of planetesimals peaked around 100AU from the central star as proposed by Augereau et al.(2001). We consider the various gas densities that have been inferred from independent observing techniques and we discuss their impact on the dust dynamics and on the disc profile in scattered light along the midplane. We show that the observed scattered light profile of the disc cannot be properly reproduced if hydrogen gas number density at 117AU exceeds 10**4 cm**-3. This corresponds to an upper limit on the total gas mass of about 0.4 Mearth assuming the gas density profile inferred by Brandeker et al.(2004) and thus to a gas to dust mass ratio smaller than 1. Our approach therefore provides an independent diagnostic for a gas depletion in the Beta-Pictoris system relative to the dust disc. Such an approach could also be used to constrain the gas content of recently identified systems like the edge-on disc around AUmic.

P. Thebault; J. -C Augereau

2005-02-22T23:59:59.000Z

13

The dust and gas content of the Crab Nebula  

E-Print Network (OSTI)

We have constructed MOCASSIN photoionization plus dust radiative transfer models for the Crab Nebula core-collapse supernova (CCSN) remnant, using either smooth or clumped mass distributions, in order to determine the chemical composition and masses of the nebular gas and dust. We computed models for several different geometries suggested for the nebular matter distribution but found that the observed gas and dust spectra are relatively insensitive to these geometries, being determined mainly by the spectrum of the pulsar wind nebula which ionizes and heats the nebula. Smooth distribution models are ruled out since they require 16-49 Msun of gas to fit the integrated optical nebular line fluxes, whereas our clumped models require 7.0 Msun of gas. neither of which can be matched by current CCSN yield predictions. A global gas-phase C/O ratio of 1.65 by number is derived, along with a He/H number ratio of 1.85, A carbonaceous dust composition is favoured by the observed gas-phase C/O ratio: amorphous carbon clu...

Owen, P J

2015-01-01T23:59:59.000Z

14

Imaging of high-speed dust particle trajectories on NSTX  

SciTech Connect

Imaging of high-speed incandescent dust particle trajectories in a tokamak plasma has been accomplished on NSTX using up to three high-speed cameras each viewing the same plasma volume from different locations and operating at speeds up to 68 000 frames/s with exposure times varying from 2 to 300 {mu}s. The dynamics of the dust trajectories can be quite complex exhibiting a large variation in both speed (10-200 m/s) and direction. Simulations of these trajectories will be utilized to ascertain the role dust may play in future machines such as ITER where significant dust production from wall erosion is expected. NSTX has numerous view ports including both tangential as well as radial views in both the midplane and lower divertors. Several vertical ports are also available so that a few specific regions in NSTX may be viewed simultaneously from several different camera positions. The cameras can be operated in the full visible spectrum but near-infrared filters can be utilized to enhance the observation of incandescent particles against a bright background. A description of the cameras and required optics is presented.

Roquemore, A. L.; Davis, W.; Kaita, R.; Skinner, C. H.; Maqueda, R.; Nishino, N. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Nova Photonics, Inc., Princeton, New Jersey 08540 (United States); Hiroshima University, Hiroshima 739-8527 (Japan)

2006-10-15T23:59:59.000Z

15

1.8 - Early Solar Nebula Grains – Interplanetary Dust Particles  

Science Journals Connector (OSTI)

Abstract This chapter examines the compositions, mineralogy, sources, and geochemical significance of interplanetary dust particles (IDPs). Despite their micrometer-scale dimensions and nanogram masses, it is now possible, primarily as a result of advances in small particle handling techniques and analytical instrumentation, to examine \\{IDPs\\} at close to atomic-scale resolution. The most widely used instruments for IDP studies are presently the analytical electron microscope, synchrotron facilities, and the ion microprobe. These laboratory analytical techniques are providing fundamental insights about IDP origins, mechanisms of formation, and grain processing phenomena that were important in the early solar system and presolar environments. At the same time, laboratory data from \\{IDPs\\} are being compared with astronomical data from dust in comets, circumstellar disks, and the interstellar medium. The direct comparison of grains in the laboratory with grains in astronomical environments is known as ‘astromineralogy.’

J.P. Bradley

2014-01-01T23:59:59.000Z

16

Detonation of Gas-Particle Flow  

Science Journals Connector (OSTI)

Fine organic or metallic particles suspended in an oxidizing or combustible gas form a reactive particle–gas mixture. Explosion pressures in such mixtures are remarkably higher than those of gaseous fuel–air m...

Fan Zhang

2009-01-01T23:59:59.000Z

17

Color-based tracking of plasma dust particles  

SciTech Connect

Color-based tracking to observe agglomeration of deposited particles inside a compact planar magnetron during plasma discharge was done by creating high dynamic range (HDR) images of photos captured by a Pentax K10D digital camera. Carbon erosion and redeposition was also monitored using the technique. The HDR images were subjected to a chromaticity-based constraint discoloration inside the plasma chamber indicating film formation or carbon redeposition. Results show that dust deposition occurs first near the evacuation pumps due to the pressure gradient and then accumulates at the positively charged walls of the chamber. This method can be applied to monitor dust formation during dusty plasma experiments without major modification of plasma devices, useful especially for large fusion reactors.

Villamayor, Michelle Marie S., E-mail: mvillamayor@nip.upd.edu.ph; Soriano, Maricor N.; Ramos, Henry J. [National Institute of Physics, University of the Philippines, Diliman, Quezon City 1101 (Philippines)] [National Institute of Physics, University of the Philippines, Diliman, Quezon City 1101 (Philippines); Kato, Shuichi; Wada, Motoi [Graduate School of Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)] [Graduate School of Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)

2014-02-15T23:59:59.000Z

18

Dust and Gas Debris Around Main Sequence Stars  

E-Print Network (OSTI)

Debris disks are dusty, gas-poor disks around main sequence stars (Backman & Paresce 1993; Lagrange, Backman & Artymowicz 2000; Zuckerman 2001). Micron-sized dust grains are inferred to exist in these systems from measurements of their thermal emission at infrared through millimeter wavelengths. The estimated lifetimes for circumstellar dust grains due to sublimation, radiation and corpuscular stellar wind effects are typically significantly smaller than the estimated ages for the stellar systems, suggesting that the grains are replenished from a reservoir, such as sublimation of comets or collisions between parent bodies. Since the color temperature for the excess emission is typically Tgr ~ 110 - 120 K, similar to that expected for small grains in the Kuiper Belt, these objects are believe to be generated by collisions between parent bodies analogous to Kuiper Belt objects in our solar system; however, a handful of systems possess warm dust, with Tgr > 300 K, at temperatures similar to the terrestrial planets. We describe the physical characteristics of debris disks, the processes that remove dust from disks, and the evidence for the presence of planets in debris disks. We also summarize observations of infalling comets toward beta Pictoris and measurements of bulk gas in debris disks.

Christine H. Chen

2005-11-22T23:59:59.000Z

19

On the relationship between visual magnitudes and gas and dust production rates in target comets to space missions  

Science Journals Connector (OSTI)

In this paper, we report the results of a cometary research, developed during the last 10 years by us, involving a criterious analysis of gas and dust production rates in comets directly associated to recent space missions. For the determination of the water release rates we use the framework of the semi-empirical model of observed visual magnitudes [Newburn Jr., R.L. A semi-empirical photometric theory of cometary gas and dust production. Application to P/Halley’s production rates, ESA–SP 174, 3, 1981; de Almeida, A.A., Singh, P.D., Huebner, W.F. Water release rates, active areas, and minimum nuclear radius derived from visual magnitudes of comets – an application to Comet 46P/Wirtanen, Planet. Space Sci. 45, 681–692, 1997; Sanzovo, G.C., de Almeida, A.A., Misra, A. et al. Mass-loss rates, dust particle sizes, nuclear active areas and minimum nuclear radii of target comets for missions STARDUST and CONTOUR, MNRAS 326, 852–868, 2001.], which once obtained, were directly converted into gas production rates. In turn, the dust release rates were obtained using the photometric model for dust particles [Newburn Jr., R.L., Spinrad, H. Spectrophotometry of seventeen comets. II – the continuum, AJ 90, 2591–2608, 1985; de Freitas Pacheco, J.A., Landaberry, S.J.C., Singh, P.D. Spectrophotometric observations of the Comet Halley during the 1985–86 apparition, MNRAS 235, 457–464, 1988; Sanzovo, G.C., Singh, P.D., Huebner, W.F. Dust colors, dust release rates, and dust-to-gas ratios in the comae of six comets, A&AS 120, 301–311, 1996.]. We applied these models to seven target comets, chosen for space missions of “fly-by”/impact and rendezvous/landing.

A.A. de Almeida; G.C. Sanzovo; P.D. Singh; A. Misra; R. Miguel Torres; D.C. Boice; W.F. Huebner

2007-01-01T23:59:59.000Z

20

Scavenging of pollutant acid substances by Asian mineral dust particles - article no. L07816  

SciTech Connect

Uptakes of sulfate and nitrate onto Asian dust particles during transport from the Asian continent to the Pacific Ocean were analyzed by using a single-particle time-of-flight mass spectrometer. Observation was conducted at Tsukuba in Japan in the springtime of 2004. Sulfate-rich dust particles made their largest contribution during the 'dust event' in the middle of April 2004. As a result of detailed analysis including backward trajectory calculations, it was confirmed that sulfate components originating from coal combustion in the continent were internally mixed with dust particles. Even in the downstream of the outflow far from the continental coastline, significant contribution of Asian dust to sulfate was observed. Asian dust plays critical roles as the carrier of sulfate over the Pacific Ocean.

Matsumoto, J.; Takahashi, K.; Matsumi, Y.; Yabushita, A.; Shimizu, A.; Matsui, I.; Sugimoto, N. [National Institute of Environmental Science, Ibaraki (Japan)

2006-04-13T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Ice Nuclei in Marine Air: Biogenic Particles or Dust?  

SciTech Connect

Ice nuclei impact clouds, but their sources and distribution in the atmosphere are still not well known. Particularly little attention has been paid to IN sources in marine environments, although evidence from field studies suggests that IN populations in remote marine regions may be dominated by primary biogenic particles associated with sea spray. In this exploratory model study, we aim to bring attention to this long-neglected topic and identify promising target regions for future field campaigns. We assess the likely global distribution of marine biogenic ice nuclei using a combination of historical observations, satellite data and model output. By comparing simulated marine biogenic immersion IN distributions and dust immersion IN distributions, we predict strong regional differences in the importance of marine biogenic IN relative to dust IN. Our analysis suggests that marine biogenic IN are most likely to play a dominant role in determining IN concentrations in near-surface-air over the Southern Ocean, so future field campaigns aimed at investigating marine biogenic IN should target that region. Climate related changes in the abundance and emission of biogenic marine IN could affect marine cloud properties, thereby introducing previously unconsidered feedbacks that influence the hydrological cycle and the Earth’s energy balance. Furthermore, marine biogenic IN may be an important aspect to consider in proposals for marine cloud brightening by artificial sea spray production.

Burrows, Susannah M.; Hoose, C.; Poschl, U.; Lawrence, M.

2013-01-11T23:59:59.000Z

22

Orbital motion of dust particles in an rf magnetron discharge. Ion drag force or neutral atom wind force  

SciTech Connect

Microparticles with sizes up to 130 {mu}m have been confined and the velocity and diameter of particles in a plasma trap of an rf magnetron discharge with an arc magnetic field have been simultaneously measured. The motion of the gas induced by electron and ion cyclotron currents has been numerically simulated using the Navier-Stokes equation. The experimental and numerical results confirm the mechanism of the orbital motion of dust particles in the magnetron discharge plasma that is associated with the orbital motion of the neutral gas accelerated by electron and ion drift flows in crossed electric and magnetic fields.

Pal, A. F.; Ryabinkin, A. N.; Serov, A. O. [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation); Dyatko, N. A.; Starostin, A. N.; Filippov, A. V., E-mail: fav@triniti.ru [Troitsk Institute for Innovation and Fusion Research (Russian Federation)

2012-03-15T23:59:59.000Z

23

Three-dimensional Reconstruction of Dust Particle Trajectories in the NSTX  

SciTech Connect

Highly mobile incandescent dust particles are routinely observed on NSTX using two fast cameras operating in the visible region. An analysis method to reconstruct dust particle trajectories in space using two fast cameras is presented in this paper. Position accuracies of a few millimeters depending on the particle's location have been achieved and particle velocities between 10 and 200 m/s have been observed. 2008 American Institute of Physics. __________________________________________________

W.U. Boeglin, A.L. Roquemore, and R. Maqueda

2009-03-06T23:59:59.000Z

24

Three-dimensional reconstruction of dust particle trajectories in the NSTX  

SciTech Connect

Highly mobile incandescent dust particles are routinely observed on NSTX using two fast cameras operating in the visible region. An analysis method to reconstruct dust particle trajectories in space using two fast cameras is presented in this paper. Position accuracies of a few millimeters depending on the particle's location have been achieved and particle velocities between 10 and 200 m/s have been observed.

Boeglin, W. U. [Physics Department, Florida International University, 11200 SW 8th Street, Miami, Florida 33199 (United States); Roquemore, A. L. [Princeton Plasma Physics Laboratory, James Forrestal Campus, Rt. 1 N at Sayre Dr., Princeton, New Jersey 08543 (United States); Maqueda, R. [NOVA Photonics, P.O. Box 451, Princeton, New Jersey 08543-0451 (United States)

2008-10-15T23:59:59.000Z

25

COLD DUST BUT WARM GAS IN THE UNUSUAL ELLIPTICAL GALAXY NGC 4125  

SciTech Connect

Data from the Herschel Space Observatory have revealed an unusual elliptical galaxy, NGC 4125, which has strong and extended submillimeter emission from cold dust but only very strict upper limits to its CO and H I emission. Depending on the dust emissivity, the total dust mass is 2-5 × 10{sup 6} M {sub ?}. While the neutral gas-to-dust mass ratio is extremely low (<12-30), including the ionized gas traced by [C II] emission raises this limit to <39-100. The dust emission follows a similar r {sup 1/4} profile to the stellar light and the dust to stellar mass ratio is toward the high end of what is found in nearby elliptical galaxies. We suggest that NGC 4125 is currently in an unusual phase where evolved stars produced in a merger-triggered burst of star formation are pumping large amounts of gas and dust into the interstellar medium. In this scenario, the low neutral gas-to-dust mass ratio is explained by the gas being heated to temperatures ?10{sup 4} K faster than the dust is evaporated. If galaxies like NGC 4125, where the far-infrared emission does not trace neutral gas in the usual manner, are common at higher redshift, this could have significant implications for our understanding of high redshift galaxies and galaxy evolution.

Wilson, C. D.; Cridland, A.; Foyle, K.; Parkin, T. J.; Cooper, E. Mentuch [Department of Physics and Astronomy, McMaster University, Hamilton, ON L8S 4M1 (Canada)] [Department of Physics and Astronomy, McMaster University, Hamilton, ON L8S 4M1 (Canada); Roussel, H. [Institut d'Astrophysique de Paris, Université Pierre et Marie Curie, CNRS UMR 7095, F-75014 Paris (France)] [Institut d'Astrophysique de Paris, Université Pierre et Marie Curie, CNRS UMR 7095, F-75014 Paris (France); Sauvage, M.; Lebouteiller, V.; Madden, S. [Laboratoire AIM, CEA/DSM-CNRS-Université Paris Diderot DAPNIA/Service d'Astrophysique, Bât. 709, CEA-Saclay, F-91191 Gif-sur-Yvette Cedex (France)] [Laboratoire AIM, CEA/DSM-CNRS-Université Paris Diderot DAPNIA/Service d'Astrophysique, Bât. 709, CEA-Saclay, F-91191 Gif-sur-Yvette Cedex (France); Smith, M. W. L.; Gear, W. [School of Physics and Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA (United Kingdom)] [School of Physics and Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA (United Kingdom); Baes, M.; De Looze, I. [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium)] [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium); Bendo, G. [UK ALMA Regional Centre Node, Jodrell Bank Center for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom)] [UK ALMA Regional Centre Node, Jodrell Bank Center for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Boquien, M.; Boselli, A.; Ciesla, L. [Aix-Marseille Université, CNRS, LAM (Laboratoire d'Astrophysique de Marseille) UMR 7326, F-13388 Marseille (France)] [Aix-Marseille Université, CNRS, LAM (Laboratoire d'Astrophysique de Marseille) UMR 7326, F-13388 Marseille (France); Clements, D. L. [Astrophysics Group, Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ (United Kingdom)] [Astrophysics Group, Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ (United Kingdom); Cooray, A. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States)] [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Galametz, M. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)] [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); and others

2013-10-20T23:59:59.000Z

26

Brownleeite: A new manganese silicide mineral in an interplanetary dust particle  

Science Journals Connector (OSTI)

...NASA has been routinely collecting IDPs and has maintained the Cosmic Dust Curatorial Facility (containing a class 10-100 cleanroom) at Johnson Space Center (Warren and Zolensky 1993). The particles described here were individually removed from the collectors...

Keiko Nakamura-Messenger; Lindsay P. Keller; Simon J. Clemett; Scott Messenger; John H. Jones; Russell L. Palma; Robert O. Pepin; Wolfgang Klöck; Michael E. Zolensky; Hirokazu Tatsuoka

27

TURBULENCE-INDUCED RELATIVE VELOCITY OF DUST PARTICLES. I. IDENTICAL PARTICLES  

SciTech Connect

We study the relative velocity of inertial particles suspended in turbulent flows and discuss implications for dust particle collisions in protoplanetary disks. We simulate a weakly compressible turbulent flow, evolving 14 particle species with friction timescale, ?{sub p}, covering the entire range of scales in the flow. The particle Stokes numbers, St, measuring the ratio of ?{sub p} to the Kolmogorov timescale, are in the range 0.1 ?< St ?< 800. Using simulation results, we show that the model by Pan and Padoan gives satisfactory predictions for the rms relative velocity between identical particles. The probability distribution function (PDF) of the relative velocity is found to be highly non-Gaussian. The PDF tails are well described by a 4/3 stretched exponential function for particles with ?{sub p} ? 1-2 T{sub L}, where T{sub L} is the Lagrangian correlation timescale, consistent with a prediction based on PP10. The PDF approaches Gaussian only for very large particles with ?{sub p} ?> 54 T{sub L}. We split particle pairs at given distances into two types with low and high relative speeds, referred to as continuous and caustic types, respectively, and compute their contributions to the collision kernel. Although amplified by the effect of clustering, the continuous contribution vanishes in the limit of infinitesimal particle distance, where the caustic contribution dominates. The caustic kernel per unit cross section rises rapidly as St increases toward ? 1, reaches a maximum at ?{sub p} ? 2 T{sub L}, and decreases as ?{sub p}{sup -1/2} for ?{sub p} >> T{sub L}.

Pan, Liubin [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Padoan, Paolo, E-mail: lpan@cfa.harvard.edu, E-mail: ppadoan@icc.ub.edu [ICREA and ICC, University of Barcelona, Marti i Franquès 1, E-08028 Barcelona (Spain)

2013-10-10T23:59:59.000Z

28

Linear and nonlinear dynamics of a dust bicrystal consisting of positive and negative dust particles  

SciTech Connect

A dusty plasma crystalline configuration consisting of charged dust grains of alternating charge sign ({center_dot}{center_dot}{center_dot}/+/-/+/-/+/{center_dot}{center_dot}{center_dot}) and mass is considered. Both charge and mass of each dust species are taken to be constant. Considering the equations of longitudinal motion, a dispersion relation for linear longitudinal vibrations is derived from first principles and then analyzed. Two harmonic modes are obtained, namely, an acoustic mode and an inverse-dispersive optic-like one. The nonlinear aspects of acoustic longitudinal dust grain motion are addressed via a generalized Boussinesq (and, alternatively, a generalized Korteweg-de Vries) description.

Kourakis, I.; Shukla, P.K.; Morfill, G.E. [Institut fuer Theoretische Physik IV and Centre for Plasma Science and Astrophysics, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Max-Planck Institut fuer Extraterrestrische Physik, Giessenbachstrasse, D-85740 Garching (Germany)

2005-11-15T23:59:59.000Z

29

Gas turbine engines with particle traps  

DOE Patents (OSTI)

A gas turbine engine (10) incorporates a particle trap (46) that forms an entrapment region (73) in a plenum (24) which extends from within the combustor (18) to the inlet (32) of a radial-inflow turbine (52, 54). The engine (10) is thereby adapted to entrap particles that originate downstream from the compressor (14) and are otherwise propelled by combustion gas (22) into the turbine (52, 54). Carbonaceous particles that are dislodged from the inner wall (50) of the combustor (18) are incinerated within the entrapment region (73) during operation of the engine (10).

Boyd, Gary L. (Tempe, AZ); Sumner, D. Warren (Phoenix, AZ); Sheoran, Yogendra (Scottsdale, AZ); Judd, Z. Daniel (Phoenix, AZ)

1992-01-01T23:59:59.000Z

30

Enrichment of the dust-to-gas mass ratio in Bondi/Jeans accretion/cloud systems due to unequal changes in dust and gas incoming velocities  

E-Print Network (OSTI)

The ratio of the Bondi and Jeans lengths is used to develop a cloud-accretion model that describes both an inner Bondi-type regime where gas pressure is balanced by the gravity of a central star and an outer Jeans-type regime where gas pressure is balanced by gas self-gravity. The gas density profile provided by this model makes a smooth transition from a wind-type inner solution to a Bonnor-Ebert type outer solution. It is shown that high-velocity dust impinging on this cloud will tend to pile-up due to having a different velocity profile than gas so that the dust-to-gas ratio is substantially enriched above the 1% ISM level.

P. M. Bellan

2008-01-27T23:59:59.000Z

31

Identification of isotopically primitive interplanetary dust particles: A NanoSIMS isotopic imaging study  

E-Print Network (OSTI)

Identification of isotopically primitive interplanetary dust particles: A NanoSIMS isotopic imaging contain larger regions with more modest enrichments in 15 N, leading to average bulk N isotopic of those IDPs that have anomalous bulk N isotopic compositions. These particles typically also contain

32

Problem Set # 6 1. An factory smoke stack releases intense small spherical patch of dust particles of  

E-Print Network (OSTI)

Problem Set # 6 1. An factory smoke stack releases intense small spherical patch of dust particles. If the density (concentration) of the dust particles at the center of the patch (location of release point) after) If you wanted to track these floats for a longer time what would you have to do initially? 3. A patch

Goodman, Louis

33

DUST-TO-GAS RATIO IN THE EXTREMELY METAL-POOR GALAXY I Zw 18  

SciTech Connect

The blue compact dwarf galaxy I Zw 18 is one of the most metal-poor systems known in the local universe (12+log(O/H) = 7.17). In this work we study I Zw 18 using data from Spitzer, Herschel Space Telescope, and IRAM Plateau de Bure Interferometer. Our data set includes the most sensitive maps of I Zw 18, to date, in both the far-infrared and the CO J = 1 {yields} 0 transition. We use dust emission models to derive a dust mass upper limit of only M{sub dust} {<=} 1.1 Multiplication-Sign 10{sup 4} M{sub Sun} (3{sigma} limit). This upper limit is driven by the non-detection at 160 {mu}m, and it is a factor of 4-10 times smaller than previous estimates (depending on the model used). We also estimate an upper limit to the total dust-to-gas mass ratio of M{sub Dust}/M{sub gas} {<=} 5.0 Multiplication-Sign 10{sup -5}. If a linear correlation between the dust-to-gas mass ratio and metallicity (measured as O/H) were to hold, we would expect a ratio of 3.9 Multiplication-Sign 10{sup -4}. We also show that the infrared spectral energy distribution is similar to that of starbursting systems.

Herrera-Camus, Rodrigo; Fisher, David B.; Bolatto, Alberto D. [Department of Astronomy and Laboratory of Millimeter Astronomy, University of Maryland, College Park, MD 20742 (United States); Leroy, Adam K. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903-2475 (United States); Walter, Fabian [Max-Planck-Institut fuer Astronomie, Konigstuehl 17, D-69117 Heidelberg (Germany); Gordon, Karl D.; Roman-Duval, Julia [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Donaldson, Jessica; Melendez, Marcio [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Cannon, John M. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States)

2012-06-20T23:59:59.000Z

34

Statistical charge distribution over dust particles in a non-Maxwellian Lorentzian plasma  

SciTech Connect

On the basis of statistical mechanics and charging kinetics, the charge distribution over uniform size spherical dust particles in a non-Maxwellian Lorentzian plasma is investigated. Two specific situations, viz., (i) the plasma in thermal equilibrium and (ii) non-equilibrium state where the plasma is dark (no emission) or irradiated by laser light (including photoemission) are taken into account. The formulation includes the population balance equation for the charged particles along with number and energy balance of the complex plasma constituents. The departure of the results for the Lorentzian plasma, from that in case of Maxwellian plasma, is graphically illustrated and discussed; it is shown that the charge distribution tends to results corresponding to Maxwellian plasma for large spectral index. The charge distribution predicts the opposite charging of the dust particles in certain cases.

Mishra, S. K. [Institute for Plasma Research (IPR), Gandhinagar-382428 (India); Misra, Shikha, E-mail: shikhamish@gmail.com [Centre for Energy Studies (CES), Indian Institute of Technology Delhi (IITD), New Delhi-110016 (India)

2014-07-15T23:59:59.000Z

35

Numerical modeling of dust particle configurations in a cylindrical radio-frequency plasma reactor  

Science Journals Connector (OSTI)

In the present work, first, plasma phase variables in a cylindrical radio-frequency (rf) plasma reactor are numerically solved using the local field approximation model. Then, equilibrium configurations of a few interacting (sub-)micron-sized dust particles are obtained by integrating the particles equations for their motion and charge, accounting for the various forces acting on each particle in a three-dimensional Lagrangian framework. Direct comparison of the results with experiment demonstrates excellent qualitative agreement. Based on the ion focus phenomenon, a physical model is formulated and proven successful in simulating the vertically aligned structures.

M. Davoudabadi and F. Mashayek

2007-11-30T23:59:59.000Z

36

Generation of concentration density maxima of small dispersive coal dust particles in horizontal iodine air filter at air-dust aerosol blow  

E-Print Network (OSTI)

The spatial distributions of the small dispersive coal dust particles with the nano and micro sizes in the granular filtering medium with the cylindrical coal granules in the absorber in the horizontal iodine air filter during its long term operation at the nuclear power plant are researched. It is shown that the concentration density maxima of the small dispersive coal dust particles appear in the granular filtering medium with the cylindrical coal absorbent granules in the horizontal iodine air filter at an action by the air dust aerosol blow. The comparison of the measured aerodynamic resistances of the horizontal and vertical iodine air filters is conducted. The main conclusion is that the magnitude of the aerodynamic resistance of the horizontal iodine air filters is much smaller in comparison with the magnitude of the aerodynamic resistance of the vertical iodine air filters at the same loads of the air dust aerosol volumes. It is explained that the direction of the air dust aerosol blow and the direction of the gravitation force in the horizontal iodine air filter are orthogonal, hence the effective accumulation of the small dispersive coal dust particles takes place at the bottom of absorber in the horizontal iodine air filter. It is found that the air dust aerosol stream flow in the horizontal iodine air filter is not limited by the appearing structures, made of the precipitated small dispersive coal dust particles, in distinction from the vertical iodine air filter, in the process of long term operation of the iodine air filters at the nuclear power plant.

I. M. Neklyudov; O. P. Ledenyov; L. I. Fedorova; P. Ya. Poltinin

2013-06-11T23:59:59.000Z

37

THE GAS/DUST RATIO OF CIRCUMSTELLAR DISKS: TESTING MODELS OF PLANETESIMAL FORMATION  

SciTech Connect

We present high-resolution, near-infrared NIRSPEC observations of CO absorption toward six class II T Tauri stars: AA Tau, DG Tau, IQ Tau, RY Tau, CW Tau, and Haro 6-5b. {sup 12}CO overtone absorption lines originating from the circumstellar disk of each object were used to calculate line-of-sight gas column densities toward each source. We measured the gas/dust ratio as a function of disk inclination, utilizing measured visual extinctions and inclinations for each star. The majority of our sources show further evidence for a correlation between the gas/dust column density ratio and disk inclination similar to that found by Rettig et al.

Horne, David [New York Center for Astrobiology, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, NY 12180-3590 (United States); Gibb, Erika [Department of Physics and Astronomy, University of Missouri-St. Louis, 8001 Natural Bridge Road, St. Louis, MO 63121 (United States); Rettig, Terrence W.; Tilley, David; Balsara, Dinshaw [Center for Astrophysics, University of Notre Dame, Notre Dame, IN 46556 (United States); Brittain, Sean [Department of Physics and Astronomy, Clemson University, Clemson, SC 29634-0978 (United States)

2012-07-20T23:59:59.000Z

38

Dust continuum emission as a tracer of gas mass in galaxies  

E-Print Network (OSTI)

We use a sample of 36 galaxies from the KINGFISH (Herschel IR), HERACLES (IRAM CO), and THINGS (VLA HI) surveys to study empirical relations between Herschel infrared (IR) luminosities and the total mass of the interstellar gas (H2+HI). Such a comparison provides a simple empirical relationship without introducing the uncertainty of dust model fitting. We find tight correlations, and provide fits to these relations, between Herschel luminosities and the total gas mass integrated over entire galaxies, with the tightest, almost linear, correlation found for the longest wavelength data (SPIRE500). However, we find that accounting for the gas-phase metallicity (affecting the dust-to-gas ratio) is crucial when applying these relations to low-mass, and presumably high-redshift, galaxies. The molecular (H2) gas mass is found to be better correlated with the peak of the IR emission (e.g. PACS160), driven mostly by the correlation of stellar mass and mean dust temperature. When examining these relations as a function ...

Groves, Brent A; Leroy, Adam; Galametz, Maud; Walter, Fabian; Bolatto, Alberto; Hunt, Leslie; Dale, Daniel; Calzetti, Daniela; Croxall, Kevin; Kennicutt, Robert

2014-01-01T23:59:59.000Z

39

Mass-loss rates and dust-to-gas ratios for obscured Asymptotic Giant Branch stars of different metallicities  

E-Print Network (OSTI)

The mass-loss rates and dust-to-gas ratios of obscured Asymptotic Giant Branch (AGB) stars are investigated for samples with different initial metallicities: in the Small and Large Magellanic Clouds (SMC & LMC) and in the Milky Way. The properties of their circumstellar envelopes can be explained in a consistent way if, both for obscured M-type AGB stars and for obscured carbon stars, the total (gas+dust) mass-loss rate depends only weakly on initial metallicity whilst the dust-to-gas ratio depends approximately linearly on initial metallicity.

Jacco Th. van Loon

1999-12-02T23:59:59.000Z

40

It is well known that a rigid body impacting on a bed of fine particles or dust may resuspend some of this dust into  

E-Print Network (OSTI)

again at a different location. The traditional view is that the resuspension is the result an impacts on the bed. The interaction of the wake with the particles on the bed may lead to resuspension. 1. INTRODUCTION Resuspension of dust and sediments is important in a wide variety of contexts

Dalziel, Stuart

Note: This page contains sample records for the topic "dust particles gas" 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

Generation of concentration density maxima of small dispersive coal dust particles in horizontal iodine air filter at air-dust aerosol blow  

E-Print Network (OSTI)

The spatial distributions of the small dispersive coal dust particles with the nano and micro sizes in the granular filtering medium with the cylindrical coal granules in the absorber in the horizontal iodine air filter during its long term operation at the nuclear power plant are researched. It is shown that the concentration density maxima of the small dispersive coal dust particles appear in the granular filtering medium with the cylindrical coal absorbent granules in the horizontal iodine air filter at an action by the air dust aerosol blow. The comparison of the measured aerodynamic resistances of the horizontal and vertical iodine air filters is conducted. The main conclusion is that the magnitude of the aerodynamic resistance of the horizontal iodine air filters is much smaller in comparison with the magnitude of the aerodynamic resistance of the vertical iodine air filters at the same loads of the air dust aerosol volumes. It is explained that the direction of the air dust aerosol blow and the directi...

Neklyudov, I M; Fedorova, L I; Poltinin, P Ya

2013-01-01T23:59:59.000Z

42

Coal dust explosibility  

Science Journals Connector (OSTI)

This paper reports US Bureau of Mines (USBM) research on the explosibility of coal dusts. The purpose of this work is to improve safety in mining and other industries that process or use coal. Most of the tests were conducted in the USBM 20 litre laboratory explosibility chamber. The laboratory data show relatively good agreement with those from full-scale experimental mine tests. The parameters measured included minimum explosible concentrations, maximum explosion pressures, maximum rates of pressure rise, minimum oxygen concentrations, and amounts of limestone rock dust required to inert the coals. The effects of coal volatility and particle size were evaluated, and particle size was determined to be at least as important as volatility in determining the explosion hazard. For all coals tested, the finest sizes were the most hazardous. The coal dust explosibility data are compared to those of other hydrocarbons, such as polyethylene dust and methane gas, in an attempt to understand better the basics of coal combustion.

Kenneth L. Cashdollar

1996-01-01T23:59:59.000Z

43

Thermophoretic separation of aerosol particles from a sampled gas stream  

DOE Patents (OSTI)

A method for separating gaseous samples from a contained atmosphere that includes aerosol particles uses the step of repelling particles from a gas permeable surface or membrane by heating the surface to a temperature greater than that of the surrounding atmosphere. The resulting thermophoretic forces maintain the gas permeable surface clear of aerosol particles. The disclosed apparatus utilizes a downwardly facing heated plate of gas permeable material to combine thermophoretic repulsion and gravity forces to prevent particles of any size from contacting the separating plate surfaces.

Postma, Arlin K. (Halfway, OR)

1986-01-01T23:59:59.000Z

44

Gas insulated transmission line having tapered particle trapping ring  

DOE Patents (OSTI)

A gas-insulated transmission line includes an outer sheath, an inner conductor, insulating supports and an insulating gas. A particle-trapping ring is secured to each insulating support, and it is comprised of a central portion and two tapered end portions. The ends of the particle trapping ring have a smaller diameter than the central portion of the ring, so as to enable the use of the particle trapping ring in a curved transmission line.

Cookson, Alan H. (Pittsburgh, PA)

1982-01-01T23:59:59.000Z

45

Detection of internally mixed Asian dust with air pollution aerosols using a polarization optical particle counter and a polarization-sensitive two-wavelength lidar  

Science Journals Connector (OSTI)

Abstract East Asia is a unique region where mineral dust (Asian dust) sources are located near urban and industrial areas. Asian dust is often mixed with air pollution aerosols during transportation. It is important to understand the mixing states of Asian dust and other aerosols, because the effects on the environment and human health differ depending on the mixing state. We studied the mixing states of Asian dust using a polarization particle counter (POPC) that measures the forward scattering and the two polarization components of backscattering for single particles and a polarization-sensitive (532 nm) two-wavelength (1064 nm and 532 nm) lidar. We conducted the simultaneous observations using the POPC and the lidar in Seoul from March to December 2013 and captured the characteristics of pure Asian dust and internally mixed polluted Asian dust. POPC measurements indicated that the density of large particles was lower in polluted Asian dust that transported slowly over the polluted areas than in pure Asian dust that transported quickly from the dust source region. Moreover, the backscattering depolarization ratio was smaller for all particle sizes in polluted dust. The optical characteristics measured using the lidar were consistent with the POPC measurements. The backscattering color ratio of polluted dust was comparable to that of pure dust, but the depolarization ratio was lower for polluted dust. In addition, coarse non-spherical particles (Asian dust) almost always existed in the background, and the depolarization ratio had seasonal variation with a lower depolarization ratio in the summer. These results suggest background Asian dust particles are internally mixed in the summer.

Nobuo Sugimoto; Tomoaki Nishizawa; Atsushi Shimizu; Ichiro Matsui; Hiroshi Kobayashi

2015-01-01T23:59:59.000Z

46

Dust-to-Gas Ratios in Early-type Galaxies A. F. Crocker (University of Massachusetts Amherst), L. M. Young (New Mex-  

E-Print Network (OSTI)

Dust-to-Gas Ratios in Early-type Galaxies A. F. Crocker (University of Massachusetts Amherst), L. M. Bureau, (University of Oxford, United Kingdom), Atlas3D Team We present dust-to-gas ratios for all mass. Cold gas masses are combined molecular and atomic masses, determined from single- dish CO

Bureau, Martin

47

Observation of plasma instabilities related to dust particle growth mechanisms in electron cyclotron resonance plasmas  

SciTech Connect

Instabilities are observed in the self-bias voltage measured on a probe immersed in microwave plasma excited at Electron Cyclotron Resonance (ECR). Observed in the MHz range, they were systematically measured in dust-free or dusty plasmas (obtained for different conditions of applied microwave powers and acetylene flow rates). Two characteristic frequencies, well described as lower hybrid oscillations, can be defined. The first one, in the 60–70 MHz range, appears as a sharp peak in the frequency spectra and is observed in every case. Attributed to ions, its position shift observed with the output power highlights that nucleation process takes place in the dusty plasma. Attributed to lower hybrid oscillation of powders, the second broad peak in the 10–20 MHz range leads to the characterization of dust particles growth mechanisms: in the same way as in capacitively coupled plasmas, accumulation of nucleus confined near the probe in the magnetic field followed by aggregation takes place. Then, the measure of electrical instabilities on the self-bias voltage allows characterizing the discharge as well as the chemical processes that take place in the magnetic field region and their kinetics.

Drenik, A. [Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia) [Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); CNRS, LAPLACE, 31062 Toulouse/Université de Toulouse, UPS, INPT, LAPLACE, 118 rte de Narbonne, 31062 Toulouse Cedex 9 (France); Yuryev, P.; Clergereaux, R. [CNRS, LAPLACE, 31062 Toulouse/Université de Toulouse, UPS, INPT, LAPLACE, 118 rte de Narbonne, 31062 Toulouse Cedex 9 (France)] [CNRS, LAPLACE, 31062 Toulouse/Université de Toulouse, UPS, INPT, LAPLACE, 118 rte de Narbonne, 31062 Toulouse Cedex 9 (France); Vesel, A. [Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)] [Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Margot, J. [Groupe de Physique des Plasmas, Département de Physique, Université de Montréal, CP 6128, Succursale Centre-ville, Montréal, Québec H3C 3J7 (Canada)] [Groupe de Physique des Plasmas, Département de Physique, Université de Montréal, CP 6128, Succursale Centre-ville, Montréal, Québec H3C 3J7 (Canada)

2013-10-15T23:59:59.000Z

48

Influence by small dispersive coal dust particles of different fractional consistence on characteristics of iodine air filter at nuclear power plant  

E-Print Network (OSTI)

The main purpose of research is to determine the influence by the small dispersive coal dust particles of the different fractional consistence on the technical characteristics of the vertical iodine air filter at nuclear power plant. The research on the transport properties of the small dispersive coal dust particles in the granular filtering medium of absorber in the vertical iodine air filter is completed in the case, when the modeled aerodynamic conditions are similar to the real aerodynamic conditions. It is shown that the appearance of the different fractional consistence of small dispersive coal dust particles with the decreasing dimensions down to the micro and nano sizes at the action of the air dust aerosol stream normally results in a significant change of distribution of the small dispersive coal dust particles masses in the granular filtering medium of an absorber in the vertical iodine air filter, changing the vertical iodine air filter aerodynamic characteristics. The precise characterization of...

Neklyudov, I M; Fedorova, L I; Poltinin, P Ya

2013-01-01T23:59:59.000Z

49

High voltage gas insulated transmission line with continuous particle trapping  

DOE Patents (OSTI)

This invention provides a novel high voltage gas insulated transmission line utilizing insulating supports spaced at intervals with snap-in means for supporting a continuous trapping apparatus and said trapping apparatus having perforations and cutouts to facilitate trapping of contaminating particles and system flexibility.

Cookson, Alan H. (Pittsburgh, PA); Dale, Steinar J. (Monroeville, PA)

1983-01-01T23:59:59.000Z

50

"Dust, Ice, and Gas In Time" (DIGIT) Herschel Observations of GSS30-IRS1 in Ophiuchus  

E-Print Network (OSTI)

As a part of the "Dust, Ice, and Gas In Time" (DIGIT) key program on Herschel, we observed GSS30-IRS1, a Class I protostar located in Ophiuchus (d = 120 pc), with Herschel/Photodetector Array Camera and Spectrometer (PACS). More than 70 lines were detected within a wavelength range from 50 micron to 200 micron, including CO, H2O, OH, and two atomic [O I] lines at 63 and 145 micron. The [C II] line, known as a tracer of externally heated gas by the interstellar radiation field, is also detected at 158 micron. All lines, except [O I] and [C II], are detected only at the central spaxel of 9.4" X 9.4". The [O I] emissions are extended along a NE-SW orientation, and the [C II] line is detected over all spaxels, indicative of external PDR. The total [C II] intensity around GSS30 reveals that the far-ultraviolet radiation field is in the range of 3 to 20 G0, where G0 is in units of the Habing Field, 1.6 X 10^{-3} erg cm^{-2} s^{-1}. This enhanced external radiation field heats the envelope of GSS30-IRS1, causing the...

Je, Hyerin; Lee, Seokho; Green, Joel D; Evans, Neal J

2015-01-01T23:59:59.000Z

51

Method for minimizing contaminant particle effects in gas-insulated electrical apparatus  

DOE Patents (OSTI)

Electrical breakdown of a gas insulator in high voltage apparatus is prevented by placing an electrical insulative coating on contaminant particles in the gas insulator.

Pace, M.O.; Adcock, J.L.; Christophorou, L.G.

1984-01-01T23:59:59.000Z

52

Characterization of secondary grain dust explosions  

E-Print Network (OSTI)

dust less than 106 um . . . ~ . . ~ ~ ~ ~ 27 4 Coulter Counter particle size distribution for wheat dust less than 106 um . 28 5 Coulter Counter particle size distribution for rice dust less than 106 um ~ 29 6 Coulter Counter particle size... distribution f' or wheat/sorghum dust, less than 106 um . 7 Coulter Counter particle size distribution for soybean dust less than 106 um 31 8 Coulter Counter particle size distribution for corn dust between 106 and. 250 um 9 Coulter Counter particle size...

Schulman, Cheryl Wendler

2012-06-07T23:59:59.000Z

53

Observations of the inner coma of C/1995O1 (Hale–Bopp)—gas and dust production  

Science Journals Connector (OSTI)

Hale–Bopp (C/1995 O1) was the most productive recent comet observed in terms of gas and dust output. Since its discovery in 1995 at a distance of 7.14 AU from the Sun, the comet has been well observed, revealing the dynamics of a rare and large comet. Hale–Bopp showed strong emissions of the principle cometary gases CN, C3, and C2, as well as an abundance of dust. The production rates of these gases were found to be 1.45 × 10 28 , 1.71 × 10 28 , and 3.52 × 10 28 molecules s - 1 , respectively, with dust production, in terms of A f ? , 1.36 × 10 6 cm , as measured in the green continuum (5260 Å). The observations for this paper are presented in two groups spanning 10 days each, one group centered near 32 days prior to and the other 21 days after perihelion. The averages of dust and gas production rates show a slightly higher value for each prior to perihelion than after perihelion, consistent with a possible peak in production a few weeks prior to perihelion passage.

Brian M. Cudnik

2005-01-01T23:59:59.000Z

54

Thermophoretic separation of aerosol particles from a sampled gas stream  

DOE Patents (OSTI)

This disclosure relates to separation of aerosol particles from gas samples withdrawn from within a contained atmosphere, such as containment vessels for nuclear reactors or other process equipment where remote gaseous sampling is required. It is specifically directed to separation of dense aerosols including particles of any size and at high mass loadings and high corrosivity. The United States Government has rights in this invention pursuant to Contract DE-AC06-76FF02170 between the US Department of Energy and Westinghouse Electric Corporation.

Postma, A.K.

1984-09-07T23:59:59.000Z

55

Hot Gas Filtration of Fine and Ultra fine Particles with Liquid...  

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

Hot Gas Filtration of Fine and Ultra fine Particles with Liquid Phase Sintered SiC Ceramic DPF Hot Gas Filtration of Fine and Ultra fine Particles with Liquid Phase Sintered SiC...

56

Long-Term Changes in Gas- and Particle-Phase Emissions from On...  

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

Changes in Gas- and Particle-Phase Emissions from On-Road Diesel and Gasoline Vehicles Long-Term Changes in Gas- and Particle-Phase Emissions from On-Road Diesel and Gasoline...

57

Coupling and evaluating gas/particle mass transfer treatments for aerosol simulation and forecast  

E-Print Network (OSTI)

Coupling and evaluating gas/particle mass transfer treatments for aerosol simulation and forecast hindcasting and forecasting. The lack of an efficient yet accurate gas/particle mass transfer treatment December 2007; accepted 21 February 2008; published 12 June 2008. [1] Simulating gas/particle mass transfer

Jacobson, Mark

58

Comparison of the Coulter Multisizer and Aerodynamic Particle Sizer for obtaining the aerodynamic particle size of irregularly shaped dust  

E-Print Network (OSTI)

properties of the particles. Another method uses the Coulter Multisizer, which measures the volume of each particle that has been collected on a filter. An equivalent diameter for each particle can be found by assuming the particle is spherical, which can...

McClure, Joshua Wayne

2012-06-07T23:59:59.000Z

59

Distribution of small dispersive coal dust particles and absorbed radioactive chemical elements in conditions of forced acoustic resonance in iodine air filter at nuclear power plant  

E-Print Network (OSTI)

The physical features of distribution of the small dispersive coal dust particles and the adsorbed radioactive chemical elements and their isotopes in the absorber with the granular filtering medium with the cylindrical coal granules were researched in the case of the intensive air dust aerosol stream flow through the iodine air filter (IAF). It was shown that, at the certain aerodynamic conditions in the IAF, the generation of the acoustic oscillations is possible. It was found that the acoustic oscillations generation results in an appearance of the standing acoustic waves of the air pressure (density) in the IAF. In the case of the intensive blow of the air dust aerosol, it was demonstrated that the standing acoustic waves have some strong influences on both: 1) the dynamics of small dispersive coal dust particles movement and their accumulation in the IAF; 2) the oversaturation of the cylindrical coal granules by the adsorbed radioactive chemical elements and their isotopes in the regions, where the antin...

Ledenyov, Oleg P

2013-01-01T23:59:59.000Z

60

Analysis of degrees of loading of dust catchers at compressor stations of trunk gas pipelines  

Science Journals Connector (OSTI)

Static and cyclic stresses in areas of welding of dust catcher pipes are analyzed. To determine stresses, strains in the apparatus body in natural conditions were measured and the most loaded areas of the stru...

O. A. Priimak; E. I. Mamaeva; I. M. Rafalovich…

2005-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Influence by small dispersive coal dust particles of different fractional consistence on characteristics of iodine air filter at nuclear power plant  

E-Print Network (OSTI)

The main purpose of research is to determine the influence by the small dispersive coal dust particles of the different fractional consistence on the technical characteristics of the vertical iodine air filter at nuclear power plant. The research on the transport properties of the small dispersive coal dust particles in the granular filtering medium of absorber in the vertical iodine air filter is completed in the case, when the modeled aerodynamic conditions are similar to the real aerodynamic conditions. It is shown that the appearance of the different fractional consistence of small dispersive coal dust particles with the decreasing dimensions down to the micro and nano sizes at the action of the air dust aerosol stream normally results in a significant change of distribution of the small dispersive coal dust particles masses in the granular filtering medium of an absorber in the vertical iodine air filter, changing the vertical iodine air filter aerodynamic characteristics. The precise characterization of the aerodynamic resistance of a model of the vertical iodine air filter is completed. The comparative analysis of the technical characteristics of the vertical and horizontal iodine air filters is also made.

I. M. Neklyudov; O. P. Ledenyov; L. I. Fedorova; P. Ya. Poltinin

2013-02-18T23:59:59.000Z

62

Moon Dust and Coal Ash  

Science Journals Connector (OSTI)

... SIR,-The similarity of the description of moon dust particles and that of pulverized coal ...coalash ...

D. J. THORNE; J. D. WATT

1969-09-27T23:59:59.000Z

63

Dust-to-gas ratio, $X_{\\rm CO}$ factor and CO-dark gas in the Galactic anticentre: an observational study  

E-Print Network (OSTI)

We investigate the correlation between extinction and H~{\\sc i} and CO emission at intermediate and high Galactic latitudes ($|b|>10\\degr$) within the footprint of the Xuyi Schmidt Telescope Photometric Survey of the Galactic anticentre (XSTPS-GAC) on small and large scales. In Paper I (Chen et al. 2014), we present a three-dimensional dust extinction map within the footprint of XSTPS-GAC, covering a sky area of over 6,000\\,deg$^2$ at a spatial angular resolution of 6\\,arcmin. In the current work, the map is combined with data from gas tracers, including H~{\\sc i} data from the Galactic Arecibo L-band Feed Array H~{\\sc i} survey and CO data from the Planck mission, to constrain the values of dust-to-gas ratio $DGR=A_V/N({\\rm H})$ and CO-to-$\\rm H_2$ conversion factor $X_{\\rm CO}=N({\\rm H_2})/W_{\\rm CO}$ for the entire GAC footprint excluding the Galactic plane, as well as for selected star-forming regions (such as the Orion, Taurus and Perseus clouds) and a region of diffuse gas in the northern Galactic hemis...

Chen, B -Q; Yuan, H -B; Huang, Y; Xiang, M -S

2015-01-01T23:59:59.000Z

64

Regressing Gas/Particle Partitioning Data for Polycyclic Aromatic Hydrocarbons  

Science Journals Connector (OSTI)

Regressing Gas/Particle Partitioning Data for Polycyclic Aromatic Hydrocarbons ... Although PAHs can be emitted to the environment as a result of natural combustion processes (e.g., forest fires and volcanoes), human activities are believed to dominate global PAH emissions, because high atmospheric concentrations of PAHs are usually observed in urban and industrial areas where vehicle traffic, aluminum smelting, residential heating, and other activities emit PAHs into the atmosphere (4, 5). ... One of the earliest approaches to describing the G/P partitioning equilibrium of PAHs, known as the Junge?Pankow model, relates ? to PL using the following: The parameter A in this equation is sometimes interpreted as the product of two terms c and ?. ? is the surface area of particles in a unit volume of air (cm2·cm-3) and c (Pa·cm) is a substance-specific factor depending on ambient temper ature, compound, sorption sites, and the heats of desorption from surface and vaporization from the liquid compound (7, 10, 14). ...

Yushan Su; Ying Duan Lei; Frank Wania; Mahiba Shoeib; Tom Harner

2006-04-22T23:59:59.000Z

65

Evidence for interstellar origin of seven dust particles collected by the Stardust spacecraft  

Science Journals Connector (OSTI)

...search of optical micrographs of the aerogel collectors, manual and automated searches...frame holding ultralow-density silica aerogel tiles (8) that constitute 85% of the...and 2002. The low density of the silica aerogel enables capture of hypervelocity particles...

Andrew J. Westphal; Rhonda M. Stroud; Hans A. Bechtel; Frank E. Brenker; Anna L. Butterworth; George J. Flynn; David R. Frank; Zack Gainsforth; Jon K. Hillier; Frank Postberg; Alexandre S. Simionovici; Veerle J. Sterken; Larry R. Nittler; Carlton Allen; David Anderson; Asna Ansari; Saša Bajt; Ron K. Bastien; Nabil Bassim; John Bridges; Donald E. Brownlee; Mark Burchell; Manfred Burghammer; Hitesh Changela; Peter Cloetens; Andrew M. Davis; Ryan Doll; Christine Floss; Eberhard Grün; Philipp R. Heck; Peter Hoppe; Bruce Hudson; Joachim Huth; Anton Kearsley; Ashley J. King; Barry Lai; Jan Leitner; Laurence Lemelle; Ariel Leonard; Hugues Leroux; Robert Lettieri; William Marchant; Ryan Ogliore; Wei Jia Ong; Mark C. Price; Scott A. Sandford; Juan-Angel Sans Tresseras; Sylvia Schmitz; Tom Schoonjans; Kate Schreiber; Geert Silversmit; Vicente A. Solé; Ralf Srama; Frank Stadermann; Thomas Stephan; Julien Stodolna; Stephen Sutton; Mario Trieloff; Peter Tsou; Tolek Tyliszczak; Bart Vekemans; Laszlo Vincze; Joshua Von Korff; Naomi Wordsworth; Daniel Zevin; Michael E. Zolensky; 30714 Stardust@home dusters

2014-08-15T23:59:59.000Z

66

Advanced Gas Reactor Fuel Program's TRISO Particle Fuel Sets A New World  

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

Advanced Gas Reactor Fuel Program's TRISO Particle Fuel Sets A New Advanced Gas Reactor Fuel Program's TRISO Particle Fuel Sets A New World Record For Irradiation Performance Advanced Gas Reactor Fuel Program's TRISO Particle Fuel Sets A New World Record For Irradiation Performance November 16, 2009 - 1:12pm Addthis As part of the Office of Nuclear Energy's Next Generation Nuclear Plant (NGNP) Program, the Advanced Gas Reactor (AGR) Fuel Development Program has achieved a new international record for irradiation testing of next-generation particle fuel for use in high temperature gas reactors (HTGRs). The AGR Fuel Development Program was initiated by the Department of Energy in 2002 to develop the advanced fabrication and characterization technologies, and provide irradiation and safety performance data required to license TRISO particle fuel for the NGNP and future HTGRs. The AGR

67

Applications of high-speed dust injection to magnetic fusion  

SciTech Connect

It is now an established fact that a significant amount of dust is produced in magnetic fusion devices due to plasma-wall interactions. Dust inventory must be controlled, in particular for the next-generation steady-state fusion machines like ITER, as it can pose significant safety hazards and degrade performance. Safety concerns are due to tritium retention, dust radioactivity, toxicity, and flammability. Performance concerns include high-Z impurities carried by dust to the fusion core that can reduce plasma temperature and may even induce sudden termination of the plasma. We have recognized that dust transport, dust-plasma interactions in magnetic fusion devices can be effectively studied experimentally by injection of dust with known properties into fusion plasmas. Other applications of injected dust include diagnosis of fusion plasmas and edge localized mode (ELM)'s pacing. In diagnostic applications, dust can be regarded as a source of transient neutrals before complete ionization. ELM's pacing is a promising scheme to prevent disruptions and type I ELM's that can cause catastrophic damage to fusion machines. Different implementation schemes are available depending on applications of dust injection. One of the simplest dust injection schemes is through gravitational acceleration of dust in vacuum. Experiments at Los Alamos and Princeton will be described, both of which use piezoelectric shakers to deliver dust to plasma. In Princeton experiments, spherical particles (40 micron) have been dropped in a systematic and reproducible manner using a computer-controlled piezoelectric bending actuator operating at an acoustic (0,2) resonance. The circular actuator was constructed with a 2.5 mm diameter central hole. At resonance ({approx} 2 kHz) an applied sinusoidal voltage has been used to control the flux of particles exiting the hole. A simple screw throttle located {approx}1mm above the hole has been used to set the magnitude of the flux achieved for a given voltage. Particle fluxes ranging from a few tens of particle per second up to thousands of particles per second have been achieved using this simple device. To achieve higher dust injection speed, another key consideration is how to accelerate dust at controlled amount. In addition to gravity, other possible acceleration mechanisms include electrostatic, electromagnetic, gas-dragged, plasma-dragged, and laser-ablation-based acceleration. Features and limitations of the different acceleration methods will be discussed. We will also describe laboratory experiments on dust acceleration.

Wang, Zhehui [Los Alamos National Laboratory; Li, Yangfang [Max Planck Institute for Extraterrestrial Physics, Germany

2012-08-08T23:59:59.000Z

68

On-line gas chromatographic analysis of airborne particles  

DOE Patents (OSTI)

A method and apparatus for the in-situ, chemical analysis of an aerosol. The method may include the steps of: collecting an aerosol; thermally desorbing the aerosol into a carrier gas to provide desorbed aerosol material; transporting the desorbed aerosol material onto the head of a gas chromatography column; analyzing the aerosol material using a gas chromatograph, and quantizing the aerosol material as it evolves from the gas chromatography column. The apparatus includes a collection and thermal desorption cell, a gas chromatograph including a gas chromatography column, heated transport lines coupling the cell and the column; and a quantization detector for aerosol material evolving from the gas chromatography column.

Hering, Susanne V. (Berkeley, CA); Goldstein, Allen H. (Orinda, CA)

2012-01-03T23:59:59.000Z

69

Broken gauge symmetry in a Bose gas with constant particle number  

E-Print Network (OSTI)

The existence of broken gauge symmetries in Bose-Einstein condensates is still controversially discussed in science, since it would not conserve the total number of particles. Here, it is shown for the first time that non-random condensate and non-condensate phase distributions may arise from local particle number breaking in a Bose gas with constant particle number, while the global U(1)-gauge symmetry of the system is preserved due to particle number conservation.

Alexej Schelle

2014-12-13T23:59:59.000Z

70

The effect of particle shape on pressure drop in a turbulent gas-solid suspension  

E-Print Network (OSTI)

was to experimentally compare the pressure drop in suspensions of spherical particles versus fibrous particles in the same apparatus and at the same operating conditions. The previous investigators have varied the particle size, loading ratio (lbs. flowing solids... is for a model which will predict the suspension pressure drop based on such variables as particle size and shape, Reynolds number, loading ratio, electrostatic charge, and other variables. CHAPTER II REVIEW OF LITERATURE A. General Interest in Gas-Solid...

Coughran, Mark Thomas

1984-01-01T23:59:59.000Z

71

Preliminary analysis of graphite dust releasing behavior in accident for HTR  

SciTech Connect

The behavior of the graphite dust is important to the safety of High Temperature Gas-cooled Reactors. This study investigated the flow of graphite dust in helium mainstream. The analysis of the stresses acting on the graphite dust indicated that gas drag played the absolute leading role. Based on the understanding of the importance of gas drag, an experimental system is set up for the research of dust releasing behavior in accident. Air driven by centrifugal fan is used as the working fluid instead of helium because helium is expensive, easy to leak which make it difficult to seal. The graphite particles, with the size distribution same as in HTR, are added to the experiment loop. The graphite dust releasing behavior at the loss-of-coolant accident will be investigated by a sonic nozzle. (authors)

Peng, W.; Yang, X. Y.; Yu, S. Y.; Wang, J. [Inst. of Nuclear and New Energy Technology, Tsinghua Univ., Beijing100084 (China)

2012-07-01T23:59:59.000Z

72

An integrated performance model for high temperature gas cooled reactor coated particle fuel  

E-Print Network (OSTI)

The performance of coated fuel particles is essential for the development and deployment of High Temperature Gas Reactor (HTGR) systems for future power generation. Fuel performance modeling is indispensable for understanding ...

Wang, Jing, 1976-

2004-01-01T23:59:59.000Z

73

Modeling of gas-solid flow in a CFB riser based on computational particle fluid dynamics  

Science Journals Connector (OSTI)

A three-dimensional model for gas-solid flow in a circulating fluidized bed (CFB) riser was developed based on computational particle ... experimental data validated the CPFD model for the CFB riser. The model pr...

Yinghui Zhang; Xingying Lan; Jinsen Gao

2012-12-01T23:59:59.000Z

74

VALIDATION OF THE EQUILIBRIUM MODEL FOR GALAXY EVOLUTION TO z ? 3 THROUGH MOLECULAR GAS AND DUST OBSERVATIONS OF LENSED STAR-FORMING GALAXIES  

SciTech Connect

We combine IRAM Plateau de Bure Interferometer and Herschel PACS and SPIRE measurements to study the dust and gas contents of high-redshift star-forming galaxies. We present new observations for a sample of 17 lensed galaxies at z = 1.4-3.1, which allow us to directly probe the cold interstellar medium of normal star-forming galaxies with stellar masses of ?10{sup 10} M{sub ?}, a regime otherwise not (yet) accessible by individual detections in Herschel and molecular gas studies. The lensed galaxies are combined with reference samples of submillimeter and normal z ? 1-2 star-forming galaxies with similar far-infrared photometry to study the gas and dust properties of galaxies in the SFR-M{sub *}-redshift parameter space. The mean gas depletion timescale of main-sequence (MS) galaxies at z > 2 is measured to be only ?450 Myr, a factor of ?1.5 (?5) shorter than at z = 1 (z = 0), in agreement with a (1 + z){sup –1} scaling. The mean gas mass fraction at z = 2.8 is 40% ± 15% (44% after incompleteness correction), suggesting a flattening or even a reversal of the trend of increasing gas fractions with redshift recently observed up to z ? 2. The depletion timescale and gas fractions of the z > 2 normal star-forming galaxies can be explained under the 'equilibrium model' for galaxy evolution, in which the gas reservoir of galaxies is the primary driver of the redshift evolution of specific star formation rates. Due to their high star formation efficiencies and low metallicities, the z > 2 lensed galaxies have warm dust despite being located on the star formation MS. At fixed metallicity, they also have a gas-to-dust ratio 1.7 times larger than observed locally when using the same standard techniques, suggesting that applying the local calibration of the ?{sub GDR}-metallicity relation to infer the molecular gas mass of high-redshift galaxies may lead to systematic differences with CO-based estimates.

Saintonge, Amélie; Lutz, Dieter; Genzel, Reinhard; Tacconi, Linda J.; Berta, Stefano; Förster Schreiber, Natascha M.; Poglitsch, Albrecht; Sturm, Eckhard; Wuyts, Eva; Wuyts, Stijn [Max-Planck Institut für extraterrestrische Physik, D-85741 Garching (Germany); Magnelli, Benjamin [Argelander-Institut für Astronomy, Universität Bonn, D-53121 Bonn (Germany); Nordon, Raanan [School of Physics and Astronomy, The Raymond and Beverly Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel-Aviv 69978 (Israel); Baker, Andrew J. [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8019 (United States); Bandara, Kaushala [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 5C2 (Canada)

2013-11-20T23:59:59.000Z

75

Gas/particle partitioning of total alkyl nitrates observed with TD-LIF in Bakersfield  

E-Print Network (OSTI)

total AN (gas + aerosol) and ANaer show that on average 21% of ANs are in the condensed phaseGas/particle partitioning of total alkyl nitrates observed with TD-LIF in Bakersfield A. W. Rollins samples. These measurements show that ANs are a ubiquitous component of the OA with the ­ONO2 subunit

Cohen, Ronald C.

76

In situ measurements of gas/particle-phase transitions for atmospheric semivolatile organic compounds  

Science Journals Connector (OSTI)

...abundance, as compared to an ambient run (i.e., gas-phase and particle-phase...carbon number. Because n-alkanes are straight chained, and have very low polarity, they do not enter the particle...Diurnal and seasonal variability of gasoline-related volatile organic compound emissions...

Brent J. Williams; Allen H. Goldstein; Nathan M. Kreisberg; Susanne V. Hering

2010-01-01T23:59:59.000Z

77

Vertically aligned gas-insulated transmission line having particle traps at the inner conductor  

DOE Patents (OSTI)

Gas insulated electrical apparatus having first and second conductors separated by an insulating support within an insulating gas environment, and particle traps disposed along the surface of the high potential conductor for trapping and inactivating foreign particles which may be present within the insulating gas medium. Several embodiments of the invention were developed which are particularly suited for vertically aligned gas insulated transmission lines. The particle traps are grooves or cavities formed into the walls of the tubular inner conductor, without extending into the hollow portion of the conductor. In other embodiments, the traps are appendages or insert flanges extending from the inner conductor, with the insulator supports contacting the appendages instead of the inner conductor.

Dale, Steinar J. (Monroeville, PA)

1984-01-01T23:59:59.000Z

78

Distribution of small dispersive coal dust particles and absorbed radioactive chemical elements in conditions of forced acoustic resonance in iodine air filter at nuclear power plant  

E-Print Network (OSTI)

The physical features of distribution of the small dispersive coal dust particles and the adsorbed radioactive chemical elements and their isotopes in the absorber with the granular filtering medium with the cylindrical coal granules were researched in the case of the intensive air dust aerosol stream flow through the iodine air filter (IAF). It was shown that, at the certain aerodynamic conditions in the IAF, the generation of the acoustic oscillations is possible. It was found that the acoustic oscillations generation results in an appearance of the standing acoustic waves of the air pressure (density) in the IAF. In the case of the intensive blow of the air dust aerosol, it was demonstrated that the standing acoustic waves have some strong influences on both: 1) the dynamics of small dispersive coal dust particles movement and their accumulation in the IAF; 2) the oversaturation of the cylindrical coal granules by the adsorbed radioactive chemical elements and their isotopes in the regions, where the antinodes of the acoustic waves are positioned. Finally, we completed the comparative analysis of the theoretical calculations with the experimental results, obtained for the cases of: 1) the experimental aerodynamic modeling of physical processes of the absorbed radioactive chemical elements and their isotopes distribution in the IAF; and 2) the gamma-activation spectroscopy analysis of the absorbed radioactive chemical elements and their isotopes distribution in the IAF. We made the innovative propositions on the necessary technical modifications with the purpose to improve the IAF technical characteristics and increase its operational time at the nuclear power plant (NPP), going from the completed precise characterization of the IAF parameters at the long term operation.

Oleg P. Ledenyov; Ivan M. Neklyudov

2013-06-14T23:59:59.000Z

79

ADVANCES IN DUST DETECTION AND REMOVAL FOR TOKAMAKS  

SciTech Connect

Dust diagnostics and removal techniques are vital for the safe operation of next step fusion devices such as ITER. In the tokamak environment, large particles or fi bers can fall on the electrostatic detector potentially causing a permanent short. An electrostatic dust detector developed in the laboratory is being applied to the National Spherical Torus Experiment (NSTX). We report on the development of a gas puff system that uses helium to clear such particles from the detector. Experiments at atmospheric pressure with varying nozzle designs, backing pressures, puff durations and exit fl ow orientations have given an optimal confi guration that effectively removes particles from a 25 cm² area. Similar removal effi ciencies were observed under a vacuum base pressure of 1 mTorr. Dust removal from next step tokamaks will be required to meet regulatory dust limits. A tri-polar grid of fi ne interdigitated traces has been designed that generates an electrostatic traveling wave for conveying dust particles to a “drain.” First trials with only two working electrodes have shown particle motion in optical microscope images.

Campos, A.; Skinner, C.H.

2009-01-01T23:59:59.000Z

80

Large Aperture Electrostatic Dust Detector  

SciTech Connect

Diagnosis and management of dust inventories generated in next-step magnetic fusion devices is necessary for their safe operation. A novel electrostatic dust detector, based on a fine grid of interlocking circuit traces biased to 30 or 50 ? has been developed for the detection of dust particles on remote surfaces in air and vacuum environments. Impinging dust particles create a temporary short circuit and the resulting current pulse is recorded by counting electronics. Up to 90% of the particles are ejected from the grid or vaporized suggesting the device may be useful for controlling dust inventories. We report measurements of the sensitivity of a large area (5x5 cm) detector to microgram quantities of dust particles and review its applications to contemporary tokamaks and ITER.

C.H. Skinner, R. Hensley, and A.L Roquemore

2007-10-09T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" from the National Library of EnergyBeta (NLEBeta).
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81

Investigation of Gas Solid Fluidized Bed Dynamics with Non-Spherical Particles  

SciTech Connect

One of the largest challenges for 21st century is to fulfill global energy demand while also reducing detrimental impacts of energy generation and use on the environment. Gasification is a promising technology to meet the requirement of reduced emissions without compromising performance. Coal gasification is not an incinerating process; rather than burning coal completely a partial combustion takes place in the presence of steam and limited amounts of oxygen. In this controlled environment, a chemical reaction takes place to produce a mixture of clean synthetic gas. Gas-solid fluidized bed is one such type of gasification technology. During gasification, the mixing behavior of solid (coal) and gas and their flow patterns can be very complicated to understand. Many attempts have taken place in laboratory scale to understand bed hydrodynamics with spherical particles though in actual applications with coal, the particles are non-spherical. This issue drove the documented attempt presented here to investigate fluidized bed behavior using different ranges of non-spherical particles, as well as spherical. For this investigation, various parameters are controlled that included particle size, bed height, bed diameter and particle shape. Particles ranged from 355 µm to 1180 µm, bed diameter varied from 2 cm to 7 cm, two fluidized beds with diameters of 3.4 cm and 12.4 cm, for the spherical and non-spherical shaped particles that were taken into consideration. Pressure drop was measured with increasing superficial gas velocity. The velocity required in order to start to fluidize the particle is called the minimum fluidization velocity, which is one of the most important parameters to design and optimize within a gas-solid fluidized bed. This minimum fluidization velocity was monitored during investigation while observing variables factors and their effect on this velocity. From our investigation, it has been found that minimum fluidization velocity is independent of bed height for both spherical and non-spherical particles. Further, it decrease with decreasing particle size and decreases with decreasing bed diameter. Shadow sizing, a non-intrusive imaging and diagnostic technology, was also used to visualize flow fields inside fluidized beds for both spherical and non- spherical particles and to detect the particle sizes.

Choudhuri, Ahsan

2013-06-30T23:59:59.000Z

82

Hybrid Particle-Continuum Methods for Nonequilibrium Gas and Plasma Flows  

SciTech Connect

Two different hybrid particle-continuum methods are described for simulation of nonequilibrium gas and plasma dynamics. The first technique, used for nonequilibrium hypersonic gas flows, uses either a continuum description or a particle method throughout a flow domain based on local conditions. This technique is successful in reproducing the results of full particle simulations at a small fraction of the cost. The second method uses a continuum model of the electrons combined with a particle description of the ions and atoms for simulating plasma jets. The physical accuracy of the method is assessed through comparisons with plasma plume measurements obtained in space. These examples illustrate that the complex physical phenomena associated with nonequilibrium conditions can be simulated with physical accuracy and numerical efficiency using such hybrid approaches.

Boyd, Iain D. [Department of Aerospace Engineering, University of Michigan, Ann Arbor, MI (United States)

2011-05-20T23:59:59.000Z

83

Particle trap with dielectric barrier for use in gas insulated transmission lines  

DOE Patents (OSTI)

A gas-insulated transmission line includes an outer sheath, an inner conductor within the outer sheath, insulating supports supporting the inner conductor within the outer sheath, and an insulating gas electrically insulating the inner conductor from the outer sheath. An apertured particle trapping electrode is disposed within the outer sheath, and the electrode has a pair of dielectric members secured at each longitudinal end thereof, with the dielectric members extending outwardly from the apertured electrode.

Dale, Steinar J. (Monroeville, PA)

1982-01-01T23:59:59.000Z

84

Gas flow driven by thermal creep in dusty plasma T. M. Flanagan and J. Goree  

E-Print Network (OSTI)

Gas flow driven by thermal creep in dusty plasma T. M. Flanagan and J. Goree Department of Physics 2009 Thermal creep flow TCF is a flow of gas driven by a temperature gradient along a solid boundary to the bulk gas, causing the bulk gas to flow, thereby stirring the suspension of dust particles. This result

Goree, John

85

Design of a High Temperature Small Particle Solar Receiver for Powering a Gas Turbine Engine  

E-Print Network (OSTI)

Design of a High Temperature Small Particle Solar Receiver for Powering a Gas Turbine Engine Dr. Fletcher Miller SDSU Department of Mechanical Engineering Abstract Solar thermal power for electricity for the California desert and in other appro- priate regions worldwide. Current technology relies on steam Rankine

Ponce, V. Miguel

86

Particle and Gas Emissions from a Simulated Coal-Burning Household Fire Pit  

Science Journals Connector (OSTI)

Particle and Gas Emissions from a Simulated Coal-Burning Household Fire Pit ... Chinese anthracite and bituminous coals produce different amounts of emissions when burned in a fire pit that simulates common rural household use of these fuels. ... Here we present emissions from burning 15 different fuels in a laboratory system designed to mimic the fire pits used in Xuan Wei County, China. ...

Linwei Tian; Donald Lucas; Susan L. Fischer; S. C. Lee; S. Katharine Hammond; Catherine P. Koshland

2008-02-21T23:59:59.000Z

87

Closures for Course-Grid Simulation of Fluidized Gas-Particle Flows  

SciTech Connect

Gas-particle flows in fluidized beds and riser reactors are inherently unstable, and they manifest fluctuations over a wide range of length and time scales. Two-fluid models for such flows reveal unstable modes whose length scale is as small as ten particle diameters. Yet, because of limited computational resources, gas-particle flows in large fluidized beds are invariably simulated by solving discretized versions of the two-fluid model equations over a coarse spatial grid. Such coarse-grid simulations do not resolve the small-scale spatial structures which are known to affect the macroscale flow structures both qualitatively and quantitatively. Thus there is a need to develop filtered two-fluid models which are suitable for coarse-grid simulations and capturing the effect of the small-scale structures through closures in terms of the filtered variables. The overall objective of the project is to develop validated closures for filtered two-fluid models for gas-particle flows, with the transport gasifier as a primary, motivating example. In this project, highly resolved three-dimensional simulations of a kinetic theory based two-fluid model for gas-particle flows have been performed and the statistical information on structures in the 100-1000 particle diameters length scale has been extracted. Based on these results, closures for filtered two-fluid models have been constructed. The filtered model equations and closures have been validated against experimental data and the results obtained in highly resolved simulations of gas-particle flows. The proposed project enables more accurate simulations of not only the transport gasifier, but also many other non-reacting and reacting gas-particle flows in a variety of chemical reactors. The results of this study are in the form of closures which can readily be incorporated into existing multi-phase flow codes such as MFIX (www.mfix.org). Therefore, the benefits of this study can be realized quickly. The training provided by this project has prepared a PhD student to enter research and development careers in DOE laboratories or chemicals/energy-related industries.

Sankaran Sundaresan

2010-02-14T23:59:59.000Z

88

Constraining the structure of the transition disk HD 135344B (SAO 206462) by simultaneous modeling of multi-wavelength gas and dust observations  

E-Print Network (OSTI)

HD 135344B is an accreting (pre-) transition disk which displays emission of warm CO extending tens of AU inside its 30 AU dust cavity. We employ the dust radiative transfer code MCFOST and the thermo-chemical code ProDiMo to derive the disk structure from the simultaneous modeling of the spectral energy distribution (SED), VLT/CRIRES CO P(10) 4.75 micron, Herschel/PACS [O I] 63 micron, Spitzer-IRS, and JCMT 12CO J=3-2 spectra, VLTI/PIONIER H-band visibilities, and constraints from (sub-)mm continuum interferometry and near-IR imaging. We found a disk model able to describe simultaneously the current observations. This disk has the following structure: (1) to reproduce the SED, the near-IR interferometry data, and the CO ro-vibrational emission, refractory grains (we suggest carbon) are present inside the silicate sublimation radius (0.08 100 to account for the 870 micron continuum upper limit and the CO P(10) line flux; (5) the gas/dust ratio at 30

Carmona, A; Thi, W F; Benisty, M; Ménard, F; Grady, C; Kamp, I; Woitke, P; Olofsson, J; Roberge, A; Brittain, S; Dûchene, G; Meeus, G; Martin-Zaïdi, C; Dent, B; Bouquin, J B Le; Berger, J P

2014-01-01T23:59:59.000Z

89

White noise approach to the low density limit of a quantum particle in a gas  

E-Print Network (OSTI)

The white noise approach to the investigation of the dynamics of a quantum particle interacting with a dilute and in general non-equilibrium gaseous environment in the low density limit is outlined. The low density limit is the kinetic Markovian regime when only pair collisions (i.e., collisions of the test particle with one particle of the gas at one time moment) contribute to the dynamics. In the white noise approach one first proves that the appropriate operators describing the gas converge in the sense of appropriate matrix elements to certain operators of quantum white noise. Then these white noise operators are used to derive quantum white noise and quantum stochastic equations describing the approximate dynamics of the total system consisting of the particle and the gas. The derivation is given ab initio, starting from the exact microscopic quantum dynamics. The limiting dynamics is described by a quantum stochastic equation driven by a quantum Poisson process. This equation then applied to the derivation of quantum Langevin equation and linear Boltzmann equation for the reduced density matrix of the test particle. The first part of the paper describes the approach which was developed by L. Accardi, I.V. Volovich and the author and uses the Fock-antiFock (or GNS) representation for the CCR algebra of the gas. The second part presents the approach to the derivation of the limiting equations directly in terms of the correlation functions, without use of the Fock-antiFock representation. This approach simplifies the derivation and allows to express the strength of the quantum number process directly in terms of the one-particle $S$-matrix.

Alexander Pechen

2006-07-19T23:59:59.000Z

90

Graphite dust resuspension in an HTR-10 steam generator  

Science Journals Connector (OSTI)

Abstract Graphite dust has an important effect on the safety of high-temperature gas-cooled reactors (HTR). The flow field in the steam generator was studied by the computational fluid dynamics (CFD) method, with the results indicating that the friction velocity in the windward and the leeward of the heat transfer tubes is relatively low and is higher at the sides. Further analysis of the resuspension of graphite dust indicates that the resuspension fraction reaches nearly zero for particles with a diameter less than 1 ?m, whereas it will increases as the helium velocity in the steam generator increases for particle size larger than 1 ?m. Moreover, the resuspension fraction increases as the particle size increases. The results also indicate that resuspension of the particles with sizes larger than 1 ?m exhibited obvious differences in different parts of the steam generator.

Wei Peng; Tianqi Zhang; Yanan Zhen; Suyuan Yu

2014-01-01T23:59:59.000Z

91

Particle trap to sheath contact for a gas-insulated transmission line having a corrugated outer conductor  

DOE Patents (OSTI)

A particle trap to outer elongated conductor or sheath contact for gas-insulated transmission lines. The particle trap to outer sheath contact of the invention is applicable to gas-insulated transmission lines having either corrugated or non-corrugated outer sheaths. The contact of the invention includes an electrical contact disposed on a lever arm which in turn is rotatably disposed on the particle trap and biased in a direction to maintain contact between the electrical contact and the outer sheath.

Fischer, William H. (Pittsburgh, PA); Cookson, Alan H. (Pittsburgh, PA); Yoon, Kue H. (Pittsburgh, PA)

1984-04-10T23:59:59.000Z

92

Gas accumulation in particle-rich suspensions and implications for bubble populations in crystal-rich magma  

E-Print Network (OSTI)

Gas accumulation in particle-rich suspensions and implications for bubble populations in crystal Stromboli degassing Gas mobility plays an important role in driving volcanic eruptions and controlling eruption style. The explosivity of an eruption depends, among other factors, on how easily gas can escape

Rempel, Alan W.

93

MODEL FOR DETERMINING THE EFFECTIVE THERMAL CONDUCTIVITY OF PARTICLE BEDS WITH HIGH SOLID-TO-GAS THERMAL  

E-Print Network (OSTI)

MODEL FOR DETERMINING THE EFFECTIVE THERMAL CONDUCTIVITY OF PARTICLE BEDS WITH HIGH SOLID-TO-GAS- to-gas conductivity ratio (such as Be and He). The model has the capability of accounting with high solid-to-gas thermal conductivity ratios. This paper summarizes this modeling effort. Model

Abdou, Mohamed

94

Survey of cometary particles from the Stardust mission Graciela Matrajt  

E-Print Network (OSTI)

; What is a comet ? Comet WEST Comet HaleBopp #12; Oort cloudIt extends from ~ 30 AU to ~ 150 AU; The comet activity Jets of gas and dust #12; Encounter January 2004 at 1.8 AU 234 km 6.1 km/s #12; 40x Organic matter in interplanetary particles Organic matter in Stardust particles HCN in comets Hale

Matrajt, Graciela

95

Characterization of Solidified Gas Thin Film Targets via Alpha Particle Energy Loss  

E-Print Network (OSTI)

A method is reported for measuring the thickness and uniformity of thin films of solidified gas targets. The energy of alpha particles traversing the film is measured and the energy loss is converted to thickness using the stopping power. The uniformity is determined by measuring the thickness at different positions with an array of sources. Monte Carlo simulations have been performed to study the film deposition mechanism. Thickness calibrations for a TRIUMF solid hydrogen target system are presented.

MUH collaboration; M. C. Fujiwara; G. A. Beer; J. L. Beveridge; J. L. Douglas; T. M. Huber; R. Jacot-Guillarmod; S. K. Kim; P. E. Knowles; A. R. Kunselman; M. Maier; G. M. Marshall; G. R. Mason; F. Mulhauser; A. Olin; C. Petitjean; T. A. Porcelli; J. Zmeskal

1996-10-06T23:59:59.000Z

96

On-Road Measurement of Gas and Particle Phase Pollutant Emission Factors  

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

On-Road Measurement of Gas and Particle Phase Pollutant Emission Factors On-Road Measurement of Gas and Particle Phase Pollutant Emission Factors for Individual Heavy-Duty Diesel Trucks Title On-Road Measurement of Gas and Particle Phase Pollutant Emission Factors for Individual Heavy-Duty Diesel Trucks Publication Type Journal Article Year of Publication 2012 Authors Dallmann, Timothy R., Steven J. DeMartini, Thomas W. Kirchstetter, Scott C. Herndon, Timothy B. Onasch, Ezra C. Wood, and Robert A. Harley Journal Environmental Science and Technology Volume 46 Issue 15 Pagination 8511-8518 Abstract Pollutant concentrations in the exhaust plumes of individual diesel trucks were measured at high time resolution in a highway tunnel in Oakland, CA, during July 2010. Emission factors for individual trucks were calculated using a carbon balance method, in which pollutants measured in each exhaust plume were normalized to measured concentrations of carbon dioxide. Pollutants considered here include nitric oxide, nitrogen dioxide (NO2), carbon monoxide, formaldehyde, ethene, and black carbon (BC), as well as optical properties of emitted particles. Fleet-average emission factors for oxides of nitrogen (NOx) and BC respectively decreased 30 ± 6 and 37 ± 10% relative to levels measured at the same location in 2006, whereas a 34 ± 18% increase in the average NO2 emission factor was observed. Emissions distributions for all species were skewed with a small fraction of trucks contributing disproportionately to total emissions. For example, the dirtiest 10% of trucks emitted half of total NO2 and BC emissions. Emission rates for NO2 were found to be anticorrelated with all other species considered here, likely due to the use of catalyzed diesel particle filters to help control exhaust emissions. Absorption and scattering cross-section emission factors were used to calculate the aerosol single scattering albedo (SSA, at 532 nm) for individual truck exhaust plumes, which averaged 0.14 ± 0.03.

97

Characterization of a gas burner to simulate a propellant flame and evaluate aluminum particle combustion  

SciTech Connect

This study details the characterization and implementation of a burner designed to simulate solid propellant fires. The burner was designed with the ability to introduce particles (particularly aluminum) into a gas flame. The aluminized flame conditions produced by this burner are characterized based on temperature and heat flux measurements. Using these results, flame conditions are quantified in comparison to other well-characterized reactions including hydrocarbon and propellant fires. The aluminized flame is also used to measure the burning rate of the particles. This work describes the application of this burner for re-creating small-scale propellant flame conditions and as a test platform for experiments that contribute to the development of a particle combustion model, particularly in propellant fires. (author)

Jackson, Matt [Engineering Department, West Texas A and M University, Canyon, TX 79016 (United States); Pantoya, Michelle L. [Mechanical Engineering Department, Texas Tech University, Lubbock, TX 79409 (United States); Gill, Walt [Sandia National Laboratories, Albuquerque, NM 87185 (United States)

2008-04-15T23:59:59.000Z

98

Dust Studies in DIII-D Tokamak  

SciTech Connect

Studies of submicron dust using Mie scattering from Nd:YAG lasers and video data of micron to sub-millimeter sized dust on DIII-D tokamak have provided the first data of dust sources and transport during tokamak discharges. During normal operation on DIII-D dust observation rates are low, a few events per discharge or less. The net carbon content of the dust corresponds to a carbon atom density a few orders of magnitude below the core impurity density. Statistical analysis of Mie data collected over months of operation reveal correlation of increased dust rate with increased heating power and impulsive wall loading due to edge localized modes (ELMs) and disruptions. Generation of significant amounts of dust by disruptions is confirmed by the camera data. However, dust production by disruptions alone is insufficient to account for estimated in-vessel dust inventory in DIII-D. After an extended entry vent, thousands of dust particles are observed by cameras in the first 2-3 plasma discharges. Individual particles moving at velocities up to {approx}300 m/s, breakup of larger particles into pieces, and collisions of particles with walls are observed. After {approx}70 discharges, dust levels are reduced to a few events per discharge. In order to calibrate diagnostics and benchmark modeling, milligram amounts of micron-sized carbon dust have been injected into DIII-D discharges, leading to the core carbon density increase by a factor of 2-3. Following injection, dust trajectories in the divertor are mostly in the toroidal direction, consistent with the ion drag force. Dust from the injection is observed in the outboard midplane by a fast framing camera. The observed trajectories and velocities of the dust particles are in qualitative agreement with modeling by the 3D DustT code.

Rudakov, D L; West, W P; Groth, M; Yu, J H; Boedo, J A; Bray, B D; Brooks, N H; Fenstermacher, M E; Hollmann, E M; Hyatt, A W; Krasheninnikov, S I; Lasnier, C J; Moyer, R A; Pigarov, A Y; Smirnov, R; Solomon, W M; Wong, C C

2008-04-15T23:59:59.000Z

99

Parameters of a collisional radio-frequency sheath and dust characteristics resulting from the microparticle levitation  

SciTech Connect

The screening length, the time-average electric field, and the particle charge as well as the local vertical gradients of these quantities are determined experimentally within a sheath of a capacitively coupled rf, 13.56 MHz, discharge at enhanced argon gas pressures of 30, 55, and 100 Pa. The parameters are derived directly from comparative measurements of levitation positions of the particles of different sizes and variations in the levitation heights caused by formation of new dust layers. The electrostatic effect of the horizontally extended dust layers on the sheath electric field is investigated.

Yaroshenko, V. V.; Antonova, T.; Thomas, H. M.; Morfill, G. E. [Max-Planck-Institut fuer extraterrestrische Physik, D-85741 Garching (Germany)

2009-10-15T23:59:59.000Z

100

Influence of dust on the emissivity of radiant barriers  

E-Print Network (OSTI)

(Figure 5. 2. ) as F Fr-a r-r (22) where N is the number of dust particles considered in the problem and d is the total dust coverage of the barrier. This is valid when a large dust accumulation exists, and the statistical equivalent diameter... is the mean diameter. 31 Surface (Roof) Fr Fr ? i Dust Particles Fr d is calculated to all the dust particles Figure 5. 2. Shape factor from any surface to the dust particles. The shape factors from the surrounding planes (roof deck and gables...

Noboa, Homero Luis

2012-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

DISCOVERY OF THE METHOXY RADICAL, CH{sub 3}O, TOWARD B1: DUST GRAIN AND GAS-PHASE CHEMISTRY IN COLD DARK CLOUDS  

SciTech Connect

We report on the discovery of the methoxy radical (CH{sub 3}O) toward the cold and dense core B1-b based on the observation, with the IRAM 30 m radio telescope, of several lines at 3 and 2 mm wavelengths. Besides this new molecular species we also report on the detection of many lines arising from methyl mercaptan (CH{sub 3}SH), formic acid (HCOOH), propynal (HCCCHO), acetaldehyde (CH{sub 3}CHO), dimethyl ether (CH{sub 3}OCH{sub 3}), methyl formate (CH{sub 3}OCOH), and the formyl radical (HCO). The column density of all these species is {approx_equal}10{sup 12} cm{sup -2}, corresponding to abundances of {approx_equal}10{sup -11}. The similarity in abundances for all these species strongly suggest that they are formed on the surface of dust grains and ejected to the gas phase through non-thermal desorption processes, most likely cosmic rays or secondary photons. Nevertheless, laboratory experiments indicate that the CH{sub 3}O isomer released to the gas phase is CH{sub 2}OH rather than the methoxy one. Possible gas-phase formation routes to CH{sub 3}O from OH and methanol are discussed.

Cernicharo, J.; Jimenez-Escobar, A.; Munoz Caro, G. M. [Department of Astrophysics, CAB, INTA-CSIC, Crta Torrejon, E-28850 Torrejon de Ardoz, Madrid (Spain); Marcelino, N. [NRAO, 520 Edgemont Road, Charlottesville, VA 22902 (United States); Roueff, E. [Luth, Observatoire de Paris, CNRS UMR8102, Place J. Janssen F-92190 Meudon (France); Gerin, M., E-mail: jcernicharo@cab.inta-csic.es [LERMA, Observatoire de Paris, CNRS UMR8112 and Ecole Normale Superieure, 61 avenue de l'observatoire, F-75014 Paris (France)

2012-11-10T23:59:59.000Z

102

Flying dust  

Science Journals Connector (OSTI)

... So, says Daedalus, a fluidized mass of hot dust is a sort of mobile Stirling engine, driven along by its own heat. This bold

David Jones

1992-05-14T23:59:59.000Z

103

On the Virial Series for a Gas of Particles with Uniformly Repulsive Pairwise Interaction  

E-Print Network (OSTI)

The pressure of a gas of particles with a uniformly repulsive pair interaction in a finite container is shown to satisfy (exactly as a formal object) a "viscous" Hamilton-Jacobi (H-J) equation whose solution in power series is recursively given by the variation of constants formula. We investigate the solution of the H-J and of its Legendre transform equation by the Cauchy-Majorant method and provide a lower bound to the radius of convergence on the virial series of the gas which goes beyond the threshold established by Lagrange's inversion formula. A comparison between the behavior of the Mayer and virial coefficients for different regimes of repulsion intensity is also provided.

David Brydges; Domingos H. U. Marchetti

2014-03-06T23:59:59.000Z

104

Hybrid particle traps and conditioning procedure for gas insulated transmission lines  

DOE Patents (OSTI)

A gas insulated transmission line includes an outer sheath, an inner condor within the outer sheath, insulating supports supporting the inner conductor within the outer sheath, and an insulating gas electrically insulating the inner conductor from the outer sheath. An apertured particle trapping ring is disposed within the outer sheath, and the trapping ring has a pair of dielectric members secured at each longitudinal end thereof, with the dielectric members extending outwardly from the trapping ring along an arc. A support sheet having an adhesive coating thereon is secured to the trapping ring and disposed on the outer sheath within the low field region formed between the trapping ring and the outer sheath. A conditioning method used to condition the transmission line prior to activation in service comprises applying an AC voltage to the inner conductor in a plurality of voltage-time steps, with the voltage-time steps increasing in voltage magnitude while decreasing in time duration.

Dale, Steinar J. (Monroeville, PA); Cookson, Alan H. (Churchill, PA)

1982-01-01T23:59:59.000Z

105

Gas Absorption in the KH 15D System: Further Evidence for Dust Settling in the Circumbinary Disk  

E-Print Network (OSTI)

Na I D lines in the spectrum of the young binary KH 15D have been analyzed in detail. We find an excess absorption component that may be attributed to foreground interstellar absorption, and to gas possibly associated with ...

Lawler, S. M.

106

E-Print Network 3.0 - asymmetric dust shell Sample Search Results  

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

blue-shifted emission lines, because the dust obscures more emission from receding gas; and (iii... is much faster than that expected for a typical circumstellar dust shell...

107

Particle trap to sheath non-binding contact for a gas-insulated transmission line having a corrugated outer conductor  

DOE Patents (OSTI)

A non-binding particle trap to outer sheath contact for use in gas insulated transmission lines having a corrugated outer conductor. The non-binding feature of the contact according to the teachings of the invention is accomplished by having a lever arm rotatably attached to a particle trap by a pivot support axis disposed parallel to the direction of travel of the inner conductor/insulator/particle trap assembly.

Fischer, William H. (Pittsburgh, PA)

1984-04-24T23:59:59.000Z

108

Numerical simulation of dilute and dense layered coal-dust explosions  

Science Journals Connector (OSTI)

Abstract Multidimensional time-dependent simulations were performed to study the interaction of a shock wave and resulting shear layer with layers of coal dust. The simulations used a high-order compressible numerical method for fluid dynamics and included a Eulerian kinetic-theory-based granular multiphase model applicable over a range from dense to dilute particle volume fractions. Two cases were considered: a loose dust layer with an initial volume fraction of 1%, and a dense dust layer with an initial volume fraction of 47%. For both cases, the final result is a coupled complex consisting of a shock leading a coal-dust flame. In the simulations presented here, a shock is initially produced from remnants of a natural gas detonation, which has decayed into a shock once it passes into a region containing no gaseous fuel. This shock weakens further due to mechanical and thermal losses from lifting and entraining the coal dust. The lifted dust subsequently ignites in the shock-heated air and produces a structure similar to a mixing-limited, nonpremixed flame. The flame consists of a burning coal dust wave that follows the shock. The distance between the shock and ignition point is determined by the induction length of carbon char, which is ? 170 cm and ? 15 cm for the 47% and 1% cases, respectively. The burning of coal particles is predominantly from heterogeneous reactions with carbon char, and volatilized methane combustion is a secondary effect. Air and particles are mixed by relative velocity between the gas and solid phases. Coal particles burn and produce pressure waves that accelerate the shock from Mach 2.2 to 2.6 for the dilute layer, and from Mach 1.7 to 1.8 in the dense layer.

Ryan W. Houim; Elaine S. Oran

2014-01-01T23:59:59.000Z

109

A Comprehensive Parameterization of Heterogeneous Ice Nucleation of Dust Surrogate: Laboratory Study with Hematite Particles and Its Application to Atmospheric Models  

SciTech Connect

A new heterogeneous ice nucleation parameterization that covers a wide temperature range (-36 ?C to -78 ?C) is presented. Developing and testing such an ice nucleation parameterization, which is constrained through identical experimental conditions, is critical in order to accurately simulate the ice nucleation processes in cirrus clouds. The surface-scaled ice nucleation efficiencies of hematite particles, inferred by ns, were derived from AIDA (Aerosol Interaction and Dynamics in the Atmosphere) cloud chamber measurements under water subsaturated conditions that were realized by continuously changing temperature (T) and relative humidity with respect to ice (RHice) in the chamber. Our measurements showed several different pathways to nucleate ice depending on T and RHice conditions. For instance, almost independent freezing was observed at -60 ?C < T < -50 ?C, where RHice explicitly controlled ice nucleation efficiency, while both T and RHice played roles in other two T regimes: -78 ?C < T < -60 ?C and -50 ?C < T < -36 ?C. More specifically, observations at T colder than -60 ?C revealed that higher RHice was necessary to maintain constant ns, whereas T may have played a significant role in ice nucleation at T warmer than -50 ?C. We implemented new ns parameterizations into two cloud models to investigate its sensitivity and compare with the existing ice nucleation schemes towards simulating cirrus cloud properties. Our results show that the new AIDA-based parameterizations lead to an order of magnitude higher ice crystal concentrations and inhibition of homogeneous nucleation in colder temperature regions. Our cloud simulation results suggest that atmospheric dust particles that form ice nuclei at lower temperatures, below -36 ?C, can potentially have stronger influence on cloud properties such as cloud longevity and initiation when compared to previous parameterizations.

Hiranuma, Naruki; Paukert, Marco; Steinke, Isabelle; Zhang, Kai; Kulkarni, Gourihar R.; Hoose, Corinna; Schnaiter, Martin; Saathoff, Harald; Mohler, Ottmar

2014-12-10T23:59:59.000Z

110

Simulation of dust streaming in toroidal traps: Stationary flows  

SciTech Connect

Molecular-dynamic simulations were performed to study dust motion in a toroidal trap under the influence of the ion drag force driven by a Hall motion of the ions in E x B direction, gravity, inter-particle forces, and friction with the neutral gas. This article is focused on the inhomogeneous stationary streaming motion. Depending on the strength of friction, the spontaneous formation of a stationary shock or a spatial bifurcation into a fast flow and a slow vortex flow is observed. In the quiescent streaming region, the particle flow features a shell structure which undergoes a structural phase transition along the flow direction.

Reichstein, Torben; Piel, Alexander [IEAP, Christian-Albrechts-Universitaet, D-24098 Kiel (Germany)

2011-08-15T23:59:59.000Z

111

COARSE-GRID SIMULATION OF REACTING AND NON-REACTING GAS-PARTICLE FLOWS  

SciTech Connect

The principal goal of this project, funded under the ''DOE Vision 21 Virtual Demonstration Initiative'' is virtual demonstration of circulating fluidized bed performance. We had proposed a ''virtual demonstration tool'', which is based on the open-domain CFD code MFIX. The principal challenge funded through this grant is to devise and implement in this CFD code sound physical models for the rheological characteristics of the gas-particle mixtures. Within the past year, which was the third year of the project, we have made the following specific advances. (a) We have completed a study of the impact of sub-grid models of different levels of detail on the results obtained in coarse-grid simulations of gas-particle flow. (b) We have also completed a study of a model problem to understand the effect of wall friction, which was proved in our earlier work to be very important for stable operation of standpipes in a circulating fluidized bed circuit. These are described in a greater detail in this report.

Sankaran Sundaresan

2004-03-01T23:59:59.000Z

112

Electrostatic Dust Detector with Improved Sensitivity  

SciTech Connect

Methods to measure the inventory of dust particles and to remove dust if it approaches safety limits will be required in next-step tokamaks such as ITER. An electrostatic dust detector, based on a fine grid of interlocking circuit traces, biased to 30 or 50 V, has been developed for the detection of dust on remote surfaces in air and vacuum environments. Gaining operational experience of dust detection on surfaces in tokamaks is important, however the level of dust generated in contemporary short-pulse tokamaks is comparatively low and high sensitivity is necessary to measure dust on a shot-by-shot basis. We report on modifications in the detection electronics that have increased the sensitivity of the electrostatic dust detector by a factor of up to 120, - a level suitable for measurements on contemporary tokamaks.

D.P. Boyle, C.H. Skinner, and A. L. Roquemore

2008-06-09T23:59:59.000Z

113

Radiative Effects of Dust Aerosols, Natural Cirrus Clouds and Contrails: Broadband Optical Properties and Sensitivity Studies  

E-Print Network (OSTI)

This dissertation aims to study the broadband optical properties and radiative effects of dust aerosols and ice clouds. It covers three main topics: the uncertainty of dust optical properties and radiative effects from the dust particle shape...

Yi, Bingqi

2013-07-09T23:59:59.000Z

114

THE CO-TO-H{sub 2} CONVERSION FACTOR AND DUST-TO-GAS RATIO ON KILOPARSEC SCALES IN NEARBY GALAXIES  

SciTech Connect

We present ?kiloparsec spatial resolution maps of the CO-to-H{sub 2} conversion factor (?{sub CO}) and dust-to-gas ratio (DGR) in 26 nearby, star-forming galaxies. We have simultaneously solved for ?{sub CO} and the DGR by assuming that the DGR is approximately constant on kiloparsec scales. With this assumption, we can combine maps of dust mass surface density, CO-integrated intensity, and H I column density to solve for both ?{sub CO} and the DGR with no assumptions about their value or dependence on metallicity or other parameters. Such a study has just become possible with the availability of high-resolution far-IR maps from the Herschel key program KINGFISH, {sup 12}CO J = (2-1) maps from the IRAM 30 m large program HERACLES, and H I 21 cm line maps from THINGS. We use a fixed ratio between the (2-1) and (1-0) lines to present our ?{sub CO} results on the more typically used {sup 12}CO J = (1-0) scale and show using literature measurements that variations in the line ratio do not affect our results. In total, we derive 782 individual solutions for ?{sub CO} and the DGR. On average, ?{sub CO} = 3.1 M{sub ?} pc{sup –2} (K km s{sup –1}){sup –1} for our sample with a standard deviation of 0.3 dex. Within galaxies, we observe a generally flat profile of ?{sub CO} as a function of galactocentric radius. However, most galaxies exhibit a lower ?{sub CO} value in the central kiloparsec—a factor of ?2 below the galaxy mean, on average. In some cases, the central ?{sub CO} value can be factors of 5-10 below the standard Milky Way (MW) value of ?{sub CO,{sub MW}} = 4.4 M{sub ?} pc{sup –2} (K km s{sup –1}){sup –1}. While for ?{sub CO} we find only weak correlations with metallicity, the DGR is well-correlated with metallicity, with an approximately linear slope. Finally, we present several recommendations for choosing an appropriate ?{sub CO} for studies of nearby galaxies.

Sandstrom, K. M.; Walter, F. [Max Planck Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Leroy, A. K. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Bolatto, A. D.; Wolfire, M. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Croxall, K. V.; Crocker, A. [Department of Physics and Astronomy, Mail Drop 111, University of Toledo, 2801 West Bancroft Street, Toledo, OH 43606 (United States); Draine, B. T.; Aniano, G. [Princeton University Observatory, Peyton Hall, Princeton, NJ 08544-1001 (United States); Wilson, C. D. [Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Calzetti, D. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Kennicutt, R. C.; Galametz, M. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Donovan Meyer, J. [Department of Physics and Astronomy, SUNY Stony Brook, Stony Brook, NY 11794-3800 (United States); Usero, A. [Observatorio Astronómico Nacional, Alfonso XII, 3, E-28014 Madrid (Spain); Bigiel, F. [Institut für theoretische Astrophysik, Zentrum für Astronomie der Universität Heidelberg, Albert-Ueberle Str. 2, D-69120 Heidelberg (Germany); Brinks, E. [Centre for Astrophysics Research, University of Hertfordshire, Hatfield AL10 9AB (United Kingdom); De Blok, W. J. G. [ASTRON, The Netherlands Institute for Radio Astronomy, Postbus 2, 7990-AA Dwingeloo (Netherlands); Dale, D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Engelbracht, C. W., E-mail: sandstrom@mpia.de [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); and others

2013-11-01T23:59:59.000Z

115

Reports Refractory Interplanetary Dust Particles  

Science Journals Connector (OSTI)

...the melilites [gehlenite (geh), Ca2Al-(SiAI)07, to akermanite (aker), Ca2Mg-Si207] do not appear to form from the...identifications. The po-sition ofthe melilite within the akermanite-gehlenite series could not be adequately detennined. As...

MICHAEL E. ZOLENSKY

1987-09-18T23:59:59.000Z

116

Wood Dusts  

Science Journals Connector (OSTI)

Abstract The processing of wood is common in many types of work, and generates wood dust that has been associated with acute and chronic health effects. Workers exposed to wood dust may have adverse health effects such as upper and lower respiratory symptoms, decreased lung function, asthma, contact and allergic dermatitis, idiopathic pulmonary fibrosis, and sinonasal and nasopharyngeal cancer. This article is a revision of the previous edition article by Alan J. Weinrich and Paul Demers, volume 4, pp 464–467, © 2005, Elsevier Inc.

P.A. Demers; A.J. Weinrich

2014-01-01T23:59:59.000Z

117

Current status and future development of coated fuel particles for high temperature gas-cooled reactors  

Science Journals Connector (OSTI)

The coated particles were first invented by Roy Huddle in Harwell 1957. Through five decades of development, the German UO2 coated particle and US LEU UCO coated particle represent the highly successful coated particle designs up to now. In this paper, current status as well as the failure mechanisms of coated particle so far is reviewed and discussed. The challenges associated with high temperatures for coated particles applied in future VHTR are evaluated. And future development prospects of advanced coated particle suited for higher temperatures are presented. According to the past coated fuel particle development experience, it is unwise to make multiple simultaneous changes in the coated particle design. Two advanced designs which are modifications of standard German UO2 coated particle (UO2? herein) and US UCO coated particle (TRIZO) are promising and feasible under the world-wide cooperations and efforts.

X.W. Zhou; C.H. Tang

2011-01-01T23:59:59.000Z

118

Circumstellar Dust Shells Detlef Schonberner, Matthias Steffen  

E-Print Network (OSTI)

Circumstellar Dust Shells Detlef Sch¨onberner, Matthias Steffen This research project is concerned spectra and intensity maps computed from the resulting time­dependent wind models can be compared directly as spherical grains of amor­ phous carbon with a radius of 0.05 ¯m, the adopted dust­ to­gas ratio being 1

119

Mars Exploration Rover (MER) Panoramic Camera (Pancam) Twilight Image Analysis for Determination of Planetary Boundary Layer and Dust Particle Size Parameters  

E-Print Network (OSTI)

used in models for dust storm decay, and an influence on radiative heating due to a non- static dust distribution following a storm can be expected to affect the atmospheric structure (Taylor et al., 2007; Davy et al., 2009). According to temperature... to function at varying temperatures on the Martian surface (-55?C to +5?C) while also allowing for sun-finding to aid rover navigation, digital modeling of Martian surface terrain, high-resolution imaging for sampling in an in-situ environment, and general...

Grounds, Stephanie Beth

2012-02-14T23:59:59.000Z

120

RAPID COAGULATION OF POROUS DUST AGGREGATES OUTSIDE THE SNOW LINE: A PATHWAY TO SUCCESSFUL ICY PLANETESIMAL FORMATION  

SciTech Connect

Rapid orbital drift of macroscopic dust particles is one of the major obstacles to planetesimal formation in protoplanetary disks. We re-examine this problem by considering the porosity evolution of dust aggregates. We apply a porosity model based on recent N-body simulations of aggregate collisions, which allows us to study the porosity change upon collision for a wide range of impact energies. As a first step, we neglect collisional fragmentation and instead focus on dust evolution outside the snow line, where the fragmentation has been suggested to be less significant than inside the snow line because of the high sticking efficiency of icy particles. We show that dust particles can evolve into highly porous aggregates (with internal densities of much less than 0.1 g cm{sup -3}) even if collisional compression is taken into account. We also show that the high porosity triggers significant acceleration in collisional growth. This acceleration is a natural consequence of the particles' aerodynamical properties at low Knudsen numbers, i.e., at particle radii larger than the mean free path of the gas molecules. Thanks to this rapid growth, the highly porous aggregates are found to overcome the radial drift barrier at orbital radii less than 10 AU (assuming the minimum-mass solar nebula model). This suggests that, if collisional fragmentation is truly insignificant, formation of icy planetesimals is possible via direct collisional growth of submicron-sized icy particles.

Okuzumi, Satoshi; Kobayashi, Hiroshi [Department of Physics, Nagoya University, Nagoya, Aichi 464-8602 (Japan); Tanaka, Hidekazu [Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819 (Japan); Wada, Koji, E-mail: okuzumi@nagoya-u.jp [Planetary Exploration Research Center, Chiba Institute of Technology, Narashino, Chiba 275-0016 (Japan)

2012-06-20T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Rapid Coagulation of Porous Dust Aggregates outside the Snow Line: A Pathway to Successful Icy Planetesimal Formation  

Science Journals Connector (OSTI)

Rapid orbital drift of macroscopic dust particles is one of the major obstacles to planetesimal formation in protoplanetary disks. We re-examine this problem by considering the porosity evolution of dust aggregates. We apply a porosity model based on recent N-body simulations of aggregate collisions, which allows us to study the porosity change upon collision for a wide range of impact energies. As a first step, we neglect collisional fragmentation and instead focus on dust evolution outside the snow line, where the fragmentation has been suggested to be less significant than inside the snow line because of the high sticking efficiency of icy particles. We show that dust particles can evolve into highly porous aggregates (with internal densities of much less than 0.1 g cm–3) even if collisional compression is taken into account. We also show that the high porosity triggers significant acceleration in collisional growth. This acceleration is a natural consequence of the particles' aerodynamical properties at low Knudsen numbers, i.e., at particle radii larger than the mean free path of the gas molecules. Thanks to this rapid growth, the highly porous aggregates are found to overcome the radial drift barrier at orbital radii less than 10 AU (assuming the minimum-mass solar nebula model). This suggests that, if collisional fragmentation is truly insignificant, formation of icy planetesimals is possible via direct collisional growth of submicron-sized icy particles.

Satoshi Okuzumi; Hidekazu Tanaka; Hiroshi Kobayashi; Koji Wada

2012-01-01T23:59:59.000Z

122

Gas-solid carbonation of Ca(OH)2 and CaO particles under non-isothermal and isothermal conditions by using a thermogravimetric analyzer  

E-Print Network (OSTI)

limiting the transfer of CO2. Finally, an alternative reaction mechanism is proposed for the gas in the CO2 molecule. Keywords: Gas-solid carbonation; nanosized Ca(OH)2 particles; non-isothermal; isothermal; CO2 capture. insu-00730652,version1-10Sep2012 #12;4 1. Introduction Gas-solid reactions

Boyer, Edmond

123

Dust Activity in Comet Hale-Bopp  

Science Journals Connector (OSTI)

Comet Hale-Bopp has shown an extremely elevated level ... large heliocentric distance and that the dust to gas ratio was particularly large. This final factor ... which must be addressed is how typical comet Hale

M. R. Kidger

124

Flow Mapping in a Gas-Solid Riser via Computer Automated Radioactive Particle Tracking (CARPT)  

SciTech Connect

Statement of the Problem: Developing and disseminating a general and experimentally validated model for turbulent multiphase fluid dynamics suitable for engineering design purposes in industrial scale applications of riser reactors and pneumatic conveying, require collecting reliable data on solids trajectories, velocities ? averaged and instantaneous, solids holdup distribution and solids fluxes in the riser as a function of operating conditions. Such data are currently not available on the same system. Multiphase Fluid Dynamics Research Consortium (MFDRC) was established to address these issues on a chosen example of circulating fluidized bed (CFB) reactor, which is widely used in petroleum and chemical industry including coal combustion. This project addresses the problem of lacking reliable data to advance CFB technology. Project Objectives: The objective of this project is to advance the understanding of the solids flow pattern and mixing in a well-developed flow region of a gas-solid riser, operated at different gas flow rates and solids loading using the state-of-the-art non-intrusive measurements. This work creates an insight and reliable database for local solids fluid-dynamic quantities in a pilot-plant scale CFB, which can then be used to validate/develop phenomenological models for the riser. This study also attempts to provide benchmark data for validation of Computational Fluid Dynamic (CFD) codes and their current closures. Technical Approach: Non-Invasive Computer Automated Radioactive Particle Tracking (CARPT) technique provides complete Eulerian solids flow field (time average velocity map and various turbulence parameters such as the Reynolds stresses, turbulent kinetic energy, and eddy diffusivities). It also gives directly the Lagrangian information of solids flow and yields the true solids residence time distribution (RTD). Another radiation based technique, Computed Tomography (CT) yields detailed time averaged local holdup profiles at various planes. Together, these two techniques can provide the needed local solids flow dynamic information for the same setup under identical operating conditions, and the data obtained can be used as a benchmark for development, and refinement of the appropriate riser models. For the above reasons these two techniques were implemented in this study on a fully developed section of the riser. To derive the global mixing information in the riser, accurate solids RTD is needed and was obtained by monitoring the entry and exit of a single radioactive tracer. Other global parameters such as Cycle Time Distribution (CTD), overall solids holdup in the riser, solids recycle percentage at the bottom section of the riser were evaluated from different solids travel time distributions. Besides, to measure accurately and in-situ the overall solids mass flux, a novel method was applied.

Muthanna Al-Dahhan; Milorad P. Dudukovic; Satish Bhusarapu; Timothy J. O'hern; Steven Trujillo; Michael R. Prairie

2005-06-04T23:59:59.000Z

125

Dust Charging and Transport on Surfaces  

SciTech Connect

In this paper, we review laboratory studies of dust transport on surfaces in plasmas, performed for a number of different mechanisms: 1) Dust particles were levitated in plasma sheaths by electrostatic forces balancing the gravitational force. 2) Dust was observed to spread over and lift off a surface that repels electrons in a plasma. 3) Dust was transported on surfaces having different secondary electron yields in plasma with an electron beam as a consequence of differential charging. 4) We also report a mechanism of dust transport by electric fields occurring at electron beam impact/shadow boundaries. These processes are candidates to explain the formation of dust ponds that were recently observed in craters on the asteroid Eros by the NEAR Shoemaker spacecraft.

Wang, X. [Colorado Center for Lunar Dust And Atmospheric Studies, University of Colorado, Boulder, CO 80309 (United States); Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309 (United States); Robertson, S. [Colorado Center for Lunar Dust And Atmospheric Studies, University of Colorado, Boulder, CO 80309 (United States); Department of Physics, University of Colorado, Boulder, CO 80309 (United States); Horanyi, M. [Colorado Center for Lunar Dust And Atmospheric Studies, University of Colorado, Boulder, CO 80309 (United States); Department of Physics, University of Colorado, Boulder, CO 80309 (United States); Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309 (United States)

2011-11-29T23:59:59.000Z

126

Glass Frit Clumping And Dusting  

SciTech Connect

DWPF mixes a slurry of glass frit (Frit 418) and dilute (1.5 wt%) formic acid solution with high level waste in the Slurry Mix Evaporator (SME). There would be advantages to introducing the frit in a non-slurry form to minimize water addition to the SME, however, adding completely dry frit has the potential to generate dust which could clog filters or condensers. Prior testing with another type of frit, Frit 320, and using a minimal amount of water reduced dust generation, however, the formation of hard clumps was observed. To examine options and behavior, a TTQAP [McCabe and Stone, 2013] was written to initiate tests that would address these concerns. Tests were conducted with four types of glass frit; Frit 320, DWPF Frit 418, Bekeson Frit 418 and Multi-Aspirator Frit 418. The last two frits are chemically identical to DWPF Frit 418 but smaller particles were removed by the respective vendors. Test results on Frit Clumping and Dusting are provided in this report. This report addresses the following seven questions. Short answers are provided below with more detailed answers to follow. 1. Will the addition of a small amount of water, 1.5 wt%, to dry DWPF Frit 418 greatly reduce the dust generation during handling at DWPF? a. Yes, a small scale test showed that adding a little water to the frit greatly reduced dust generation during handling. 2. Will the addition of small amounts of water to the frit cause clumping that will impair frit handling at DWPF? a. No, not with Frit 418. Although clumps were observed to form when 1.5 wt% water was mixed with DWPF Frit 418, then compressed and air-dried overnight, the clumps were easily crushed and did not form the hardened material noted when Frit 320 was tested. 3. What is the measured size distribution of dust generated when dry frit is handled? (This affects the feasibility and choice of processing equipment for removing the dust generating fraction of the frit before it is added to the SME.) a. The size distribution for the dust removed from fresh DWPF Frit 418 while it was being shaken in a small scale LabRAM test was measured. The median size on a volume basis was 7.6 ?m and 90% of the frit particles were between 1.6 and 28 ?m. The mass of dust collected using this test protocol was much less than 1% of the original frit. 4. Can the dust be removed in a small number of processing steps and without the larger frit particles continuing to spall additional dust sized particles? a. Test results using a LabRAM were inconclusive. The LaRAM performs less efficient particle size separation than the equipment used by Bekeson and Multi-Aspirator. 5. What particle size of frit is expected to create a dust problem? a. The original criterion for creating a dusting problem was those particle sizes that were readily suspended when being shaken. For that criterion calculations and Microtrac size analyses indicated that particles smaller than 37 ?m are likely dust generators. Subsequently a more sophisticated criterion for dust problem was considered, particle sizes that would become suspended in the air flow patterns inside the SME and possibly plug the condenser. That size may be larger than 37 ?m but has not yet been determined. 6. If particles smaller than 37 ?m are removed will bulk dust generation be eliminated? a. Video-taped tests were performed using three gallons each of three types of frit 418, DWPF frit, Bekeson frit and Multi-Aspirator frit. Frit was poured through air from a height of approximately eight feet into a container half filled with water. Pouring Bekeson frit or Multi-Aspirator frit generated markedly less visible dust, but there was still a significant amount, which still has the potential of causing a dust problem. 7. Can completely dry frit be poured into the SME without having dust plug the condenser at the top of the vessel? a. Because of the complexity of air currents inside the SME and the difficulty of defensible size scaling a more prototypical test will be required to answer this question. We recommend construction of a full scale

Steimke, J. L.

2013-09-26T23:59:59.000Z

127

Separation of Fine Particles from Gases in Wet Flue Gas Desulfurization System Using a Cascade of Double Towers  

Science Journals Connector (OSTI)

Separation of Fine Particles from Gases in Wet Flue Gas Desulfurization System Using a Cascade of Double Towers ... The authors thank the High-Tech Research and Development Program of China (No. 2008AA05Z306), the Natural Science Foundation of Jiangsu Province (No. BK2008283), and the Scientific Research Foundation of Graduate School of Southeast University for their financial support. ... with high performance by cascading packed columns. ...

Jingjing Bao; Linjun Yang; Shijuan Song; Guilong Xiong

2012-02-15T23:59:59.000Z

128

Measurements of ultrafine particles from a gas-turbine burning biofuels  

SciTech Connect

Measurements of ultrafine particles have been performed at the exhaust of a low emission microturbine for power generation. This device has been fuelled with liquid fuels, including a commercial diesel oil, a mixture of the diesel oil with a biodiesel and kerosene, and tested under different loads. Primarily attention has been focused on the measurements of the size distribution functions of the particles emitted from the system by using particle differential mobility analysis. A bimodal size distribution function of the particle emitted has been found in all the examined conditions. Burning diesel oil, the first mode of the size distribution function of the combustion-formed particles is centered at around 2-3 nm, whereas the second mode is centered at about 20-30 nm. The increase of the turbine load and the addition of 50% of biodiesel has not caused changes in the shape of size distribution of the particles. A slightly decrease of the amount of particle formed has been found. By using kerosene the amount of emitted particles increases of more than one order of magnitude. Also the shape of the size distribution function changes with the first mode shifted towards larger particles of the order of 8-10 nm but with a lower emission of larger 20-30 nm particles. Overall, in this conditions, the mass concentration of particles is increased respect to the diesel oil operation. Particle sizes measured with the diesel oil have been compared with the results on a diesel engine operated in the same power conditions and with the same fuel. Measurements have showed that the mean sizes of the formed particles do not change in the two combustion systems. However, diesel engine emits a number concentration of particles more than two orders of magnitude higher in the same conditions of power and with the same fuel. By running the engine in more premixed-like conditions, the size distribution function of the particles approaches that measured by burning kerosene in the microturbine indicating that the distribution function of the sizes of the emitted particles can be strongly affected by combustion conditions. (author)

Allouis, C.; Beretta, F.; Minutolo, P.; Pagliara, R. [Istituto di Ricerche sulla Combustione, CNR, Piazzale V. Tecchio, 80, 80125 Napoli (Italy); Sirignano, M.; Sgro, L.A.; D'Anna, A. [Dipartimento di Ingegneria Chimica, Universita di Napoli Federico II, Piazzale V. Tecchio, 80, 80125 Napoli (Italy)

2010-04-15T23:59:59.000Z

129

Photochemical Oxidant Processes in the Presence of Dust: An Evaluation of the Impact of Dust on Particulate Nitrate and Ozone Formation  

Science Journals Connector (OSTI)

The influence of dust on the tropospheric photochemical oxidant cycle is studied through the use of a detailed coupled aerosol and gas-phase chemistry model. Dust is a significant component of the troposphere throughout Asia and provides a ...

Yang Zhang; Young Sunwoo; Veerabhadra Kotamarthi; Gregory R. Carmichael

1994-07-01T23:59:59.000Z

130

Effective ionization coefficients, electron drift velocities, and limiting breakdown fields for gas mixtures of possible interest to particle detectors  

SciTech Connect

We have measured the gas-density, N, normalized effective ionization coefficient, {bar a}/N, and the electron drift velocity, w, as a function of the density-reduced electric field, E/N, and obtained the limiting, (E/N){sub lim}, value of E/N for the unitary gases Ar, CO{sub 2}, and CF{sub 4}, the binary gas mixtures CO{sub 2}:Ar (20: 80), CO{sub 2}:CH{sub 4} (20:80), and CF{sub 4}:Ar (20:80), and the ternary gas mixtures CO{sub 2}:CF{sub 4}:Ar (10:10:80) and H{sub 2}O: CF{sub 4}:Ar (2:18:80). Addition of the strongly electron thermalizing gas CO{sub 2} or H{sub 2}O to the binary mixture CF{sub 4}:Ar (1) cools'' the mixture (i.e., lowers the electron energies), (2) has only a small effect on the magnitude of w(E/N) in the E/N range employed in the particle detectors, and (3) increases {bar a}/N for E/N {ge} 50 {times} 10{sup {minus}17} V cm{sup 2}. The increase in {bar a}/N, even though the electron energies are lower in the ternary mixture, is due to the Penning ionization of CO{sub 2}(or H{sub 2}O) in collisions with excited Ar* atoms. The ternary mixtures -- being fast, cool, and efficient -- have potential for advanced gas-filled particle detectors such as those for the SCC muon chambers. 17 refs., 8 figs., 1 tab.

Datskos, P.G. (Tennessee Univ., Knoxville, TN (United States). Dept. of Physics); Christophorou, L.G.; Carter, J.G. (Oak Ridge National Lab., TN (United States))

1991-01-01T23:59:59.000Z

131

Development of Improved Models and Designs for Coated-Particle Gas Reactor Fuels -- Final Report under the International Nuclear Energy Research Initiative (I-NERI)  

SciTech Connect

The objective of this INERI project was to develop improved fuel behavior models for gas reactor coated-particle fuels and to explore improved coated-particle fuel designs that could be used reliably at very high burnups and potentially in gas-cooled fast reactors. Project participants included the Idaho National Engineering Laboratory (INEEL), Centre Étude Atomique (CEA), and the Massachusetts Institute of Technology (MIT). To accomplish the project objectives, work was organized into five tasks.

David Petti; Philippe Martin; Mayeul Phélip; Ronald Ballinger; Petti does not have NT account

2004-12-01T23:59:59.000Z

132

PHYS 626 --Fundamentals of Plasma Physics --Section 5.6-5.7 1. A simple collision model (Lorentz gas model) is to assume that a particle  

E-Print Network (OSTI)

gas model) is to assume that a particle experience s collisions per unit time and have a change. The Lorentz gas model can describe well collisions between electron and neutrals, or even between ionsPHYS 626 -- Fundamentals of Plasma Physics -- Section 5.6-5.7 1. A simple collision model (Lorentz

Ng, Chung-Sang

133

Effect of Synthesis Condition and Annealing on the Sensitivity and Stability of Gas Sensors Made of Zn-Doped y-Fe2O3 Particles  

E-Print Network (OSTI)

-synthesized and annealed particles on interdigitated electrodes. The response of the gas sensor to acetone vapor, H2 in dry synthetic air was measured before and after three days of aging. High-temperature flame (H2/O2) generated nanometer-sized particles; lower...

Kim, Taeyang

2010-10-12T23:59:59.000Z

134

DEVELOPMENT OF A NEW HIGH TEMPERATURE GAS RECEIVER UTILIZING SMALL PARTICLES  

E-Print Network (OSTI)

Symposium on Solar Thermal Power and Energy Systems,solar to thermal conversion is accomplished by a dispersion of ultra~fine partlcles suspended in a gas to absorb radlant energy

Hunt, Arlon J.

2012-01-01T23:59:59.000Z

135

The effect of oxide layers on gas-generating hydride particles during production of aluminium foams  

SciTech Connect

Melt routes to metallic foam production offer attractions of low cost and the potential for good microstructural control. In situ gas generation may be preferable to external gas injection in terms of the important objective of generating a fine and uniform cell structure. The main difficulty with this approach has been that of ensuring that the gas-generating powder is suitably dispersed throughout the melt before the gas is released and the cells are formed. In the present paper, procedures are outlined for preparation of powders for use in aluminium melts, where gas will be released only after a suitable delay, allowing the powders to first become well-dispersed in the melt and solidification to start. Pre-treatment of the foaming agent also facilitates a flexible production of castings with various porosity at the same processing conditions simply by varying the thickness of a diffusion barrier layer on the gas-releasing agent. The role of the melt viscosity history, as a function of a heat extraction rate from the solidifying melt and an alloy composition, on the final porosity of the castings is also briefly discussed.

Gergely, V.; Clyne, T.W. [Univ. of Cambridge (United Kingdom). Dept. of Materials Science and Metallurgy

1998-12-31T23:59:59.000Z

136

Coagulation, fragmentation and radial motion of solid particles in protoplanetary disks  

E-Print Network (OSTI)

The growth of solid particles towards meter sizes in protoplanetary disks has to circumvent at least two hurdles, namely the rapid loss of material due to radial drift and particle fragmentation due to destructive collisions. In this paper, we present the results of numerical simulations with more and more realistic physics involved. Step by step, we include various effects, such as particle growth, radial/vertical particle motion and dust particle fragmentation in our simulations. We demonstrate that the initial dust-to-gas ratio is essential for the particles to overcome the radial drift barrier. If this value is increased by a factor of 2 compared with the canonical value for the interstellar medium, km-sized bodies can form in the inner disk 30 m/s), particles are able to grow to larger sizes in low turbulent disks. We also find that less than 5% of the small dust grains remain in the disk after 1 Myrs due to radial drift, no matter whether fragmentation is included in the simulations or not. In this paper, we also present considerable improvements to existing algorithms for dust-particle coagulation, which speed up the coagulation scheme by a factor of 10 thousand.

F. Brauer; C. P. Dullemond; Th. Henning

2007-11-14T23:59:59.000Z

137

Dust Measurement With Thomson Scattering In FTU  

SciTech Connect

The size distribution of dust particles present in FTU after disruptions has been evaluated in the range 0.05 {mu}m-0.1 {mu}m using the Thomson scattering system. Rayleigh approximation has been used to estimate the dust size. The distribution, although the radii considered do not differ more than an order of magnitude, behave like a power law. The laser energy density far exceed that necessary to vaporize, at least partially, the particles. This can affect the previous estimate of the particle sizes, and suggests that the effective radii might be larger than the estimated values. A preliminary analysis on the broad band signal is presented.

Giovannozzi, E.; Castaldo, C.; Maddaluno, G.; Rydzy, A. [Associazione EURATOM-ENEA sulla fusione, CR Frascati, c.p. 65, 00044 Frascati, RM (Italy); Ratynskaia, S. [Royal Institute of Technology (KTH), SE-100 44 Stockholm (Sweden)

2008-03-12T23:59:59.000Z

138

Studies on hydrogen plasma and dust charging in low-pressure filament discharge  

SciTech Connect

The effect of working gas pressure and dust charging on electron energy probability function has been studied for hydrogen plasma in a multi-dipole dusty plasma device. A cylindrical Langmuir probe is used to evaluate the plasma parameters and electron energy probability function (EEPF) for different working pressures. For lower energy range (below 10?eV), the EEPF follows a bi-Maxwellian shape at very low pressure (6 × 10{sup ?5}?mbar), while elevating the working pressure up to ?2 × 10{sup ?3} mbar, the shape of the EEPF transforms into a single Maxwellian. Some dip structures are observed at high energy range (??>?10?eV) in the EEPF of hydrogen plasma at all the working conditions. In presence of dust particles, it is observed that the shape of the EEPF changes due to the redistribution of the high and low-energy electron populations. Finally, the effect of working pressure on charge accumulation on dust particles is studied with the help of a Faraday cup and electrometer. From the observations, a strong influence of working pressure on plasma parameters, EEPF and dust charging is observed.

Kakati, B., E-mail: bharatkakati15@gmail.com; Kalita, D.; Kausik, S. S.; Saikia, B. K. [Centre of Plasma Physics, Institute for Plasma Research, Nazirakhat, Sonapur 782 402, Kamrup, Assam (India); Bandyopadhyay, M. [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India)

2014-08-15T23:59:59.000Z

139

Development of Improved Models and Designs for Coated-Particle Gas Reactor Fuels (I-NERI Annual Report)  

SciTech Connect

The objective of this INERI project is to develop improved fuel behavior models for gas reactor coated particle fuels and to develop improved coated-particle fuel designs that can be used reliably at very high burnups and potentially in fast gas-cooled reactors. Thermomechanical, thermophysical, and physiochemical material properties data were compiled by both the US and the French and preliminary assessments conducted. Comparison between U.S. and European data revealed many similarities and a few important differences. In all cases, the data needed for accurate fuel performance modeling of coated particle fuel at high burnup were lacking. The development of the INEEL fuel performance model, PARFUME, continued from earlier efforts. The statistical model being used to simulate the detailed finite element calculations is being upgraded and improved to allow for changes in fuel design attributes (e.g. thickness of layers, dimensions of kernel) as well as changes in important material properties to increase the flexibility of the code. In addition, modeling of other potentially important failure modes such as debonding and asphericity was started. A paper on the status of the model was presented at the HTR-2002 meeting in Petten, Netherlands in April 2002, and a paper on the statistical method was submitted to the Journal of Nuclear Material in September 2002. Benchmarking of the model against Japanese and an older DRAGON irradiation are planned. Preliminary calculations of the stresses in a coated particle have been calculated by the CEA using the ATLAS finite element model. This model and the material properties and constitutive relationships will be incorporated into a more general software platform termed Pleiades. Pleiades will be able to analyze different fuel forms at different scales (from particle to fuel body) and also handle the statistical variability in coated particle fuel. Diffusion couple experiments to study Ag and Pd transport through SiC were conducted. Analysis and characterization of the samples continues. Two active transport mechanisms are proposed: diffusion in SiC and release through SiC cracks or another, as yet undetermined, path. Silver concentration profiles determined by XPS analysis suggest diffusion within the SiC layer, most likely dominated by grain boundary diffusion. However, diffusion coefficients calculated from mass loss measurements suggest a much faster release path, postulated as small cracks or flaws that provide open paths with little resistance to silver migration. Work is ongoing to identify and characterize this path. Work on Pd behavior has begun and will continue next year.

Petti, David Andrew; Maki, John Thomas; Languille, Alain; Martin, Philippe; Ballinger, Ronald

2002-11-01T23:59:59.000Z

140

The effects of gas adsorption on particle shapes in supported platinum catalysts  

SciTech Connect

Previous work has shown that the shapes of the metal particles in a supported platinum catalyst are substantially altered when the catalyst is treated in an appropriate adages. However, at present it is unclear why the shape changes occur. In the work here, simple first-order calculations were done to examine the effects of hydrogen, nitrogen, and carbon monoxide on the equilibrium crystal shape of the platinum particles in a supported platinum catalyst. The calculation assumed that the main effect of the gaseous environment was to change the surface free energy of the facets on the platinum particles. The results of the calculations showed that when a clean platinum particle is equilibrated in nitrogen, the shape should not change significantly. However, Pt(100) facets should grow in hydrogen while Pt(210) facets should grow in carbon monoxide. By comparison, previous experiments have shown the Pt(100) facets do grow in hydrogen. Little change in shape is observed in nitrogen. Thus, it seems that changes in the surface free energy of the facets in the metal particles on a supported metal catalyst due to the presence of an adgas play an important role in the shape changes which are observed.

Shi, A.C.; Masel, R.I. (Univ. of Illinois, Urbana (USA))

1989-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" from the National Library of EnergyBeta (NLEBeta).
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141

Quantum lattice gas model of Dirac particles in 1+1 dimensions  

E-Print Network (OSTI)

Presented is a quantum computing representation of Dirac particle dynamics. The approach employs an operator splitting method that is an analytically closed-form product decomposition of the unitary evolution operator. This allows the Dirac equation to be cast as a unitary finite-difference equation in a high-energy limit. The split evolution operator (with separate kinetic and interaction terms) is useful for efficient quantum simulation. For pedagogical purposes, here we restrict the treatment to Dirac particle dynamics in 1+1 spacetime dimensions. Independent derivations of the quantum algorithm are presented and the model's validity is tested in several quantum simulations by comparing the numerical results against analytical predictions. Using the relativistic quantum algorithm in the case when mc^2 >> pc, quantum simulations of a nonrelativistic particle in an external scalar square well and parabolic potential is presented.

Jeffrey Yepez

2013-07-12T23:59:59.000Z

142

Particle number fluctuations in nuclear collisions within excluded volume hadron gas model  

E-Print Network (OSTI)

The multiplicity fluctuations are studied in the van der Waals excluded volume hadron-resonance gas model. The calculations are done in the grand canonical ensemble within the Boltzmann statistics approximation. The scaled variances for positive, negative and all charged hadrons are calculated along the chemical freeze-out line of nucleus-nucleus collisions at different collision energies. The multiplicity fluctuations are found to be suppressed in the van der Waals gas. The numerical calculations are presented for two values of hard-core hadron radius, $r=0.3$ fm and 0.5 fm, as well as for the upper limit of the excluded volume suppression effects.

M. I. Gorenstein; M. Hauer; D. O. Nikolajenko

2007-02-26T23:59:59.000Z

143

Airborne dust in Saudi Arabia : source areas, entrainment, simulation and composition.  

E-Print Network (OSTI)

??Spatial and temporal characteristics of dust storm activity in Saudi Arabia has been established using coarse-particle (PM10) dust concentrations recorded by the KACST monitoring network… (more)

Alharbi, Badr Hadhidh A

2009-01-01T23:59:59.000Z

144

Particle Velocity Distributions and Ionization Processes in a Gas-Puff Z Pinch  

Science Journals Connector (OSTI)

We have measured the time-dependent radial velocity distributions of singly to five times ionized ions in an imploding plasma shell by observing the spectral shapes and intensities of emission lines in various directions. An ionization wave propagating much faster than the local radial ion velocities is observed. The ionization front velocity is found to be consistent with estimates of electron heat conduction into the plasma-neutral layer. The ionization and velocity histories of the particles are experimentally determined. The mechanisms of momentum transfer to the particles are also determined and compared with existing models.

M. E. Foord; Y. Maron; G. Davara; L. Gregorian; A. Fisher

1994-06-13T23:59:59.000Z

145

STRATOSPHERIC DUST COLLECTION: AN ISOTOPIC SURVEY OF TERRESTRIAL AND COSMIC PARTICLES; FJ. Stadermann, R.M. Walker, and E. Zinner, McDonnell Center for the Space Sci-  

E-Print Network (OSTI)

, Washington University, St. Louis, Missouri 63130, USA. We report isotopic measurements of H, C, N, and Si-picked from the col- lector flag, cleansed of the silicon oil that was used as capture medium, and the size.g., isotopic anomalies [2,4],noble gas contents [5],and solar flaretracks [6], althoughthe absenceof any

146

Particle simulation of collision dynamics for ion beam injection into a rarefied gas  

SciTech Connect

This study details a comparison of ion beam simulations with experimental data from a simplified plasma test cell in order to study and validate numerical models and environments representative of electric propulsion devices and their plumes. The simulations employ a combination of the direct simulation Monte Carlo and particle-in-cell methods representing xenon ions and atoms as macroparticles. An anisotropic collision model is implemented for momentum exchange and charge exchange interactions between atoms and ions in order to validate the post-collision scattering behaviors of dominant collision mechanisms. Cases are simulated in which the environment is either collisionless or non-electrostatic in order to prove that the collision models are the dominant source of low- and high-angle particle scattering and current collection within this environment. Additionally, isotropic cases are run in order to show the importance of anisotropy in these collision models. An analysis of beam divergence leads to better characterization of the ion beam, a parameter that requires careful analysis. Finally, suggestions based on numerical results are made to help guide the experimental design in order to better characterize the ion environment.

Giuliano, Paul N.; Boyd, Iain D. [Department of Aerospace Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2013-03-15T23:59:59.000Z

147

Single-particle spectral density of the unitary Fermi gas: Novel approach based on the operator product expansion, sum rules and the maximum entropy method  

E-Print Network (OSTI)

Making use of the operator product expansion, we derive a general class of sum rules for the imaginary part of the single-particle self-energy of the unitary Fermi gas. The sum rules are analyzed numerically with the help of the maximum entropy method, which allows us to extract the single-particle spectral density as a function of both energy and momentum. These spectral densities contain basic information on the properties of the unitary Fermi gas, such as the dispersion relation and the superfluid pairing gap, for which we obtain reasonable agreement with the available results based on quantum Monte-Carlo simulations.

Gubler, Philipp; Hatsuda, Tetsuo; Nishida, Yusuke

2015-01-01T23:59:59.000Z

148

Niamey Dust Observations  

DOE Data Explorer (OSTI)

Niamey aerosol are composed of two main components: dust due to the proximity of the Sahara Desert, and soot from local and regional biomass burning. The purpose of this data product is to identify when the local conditions are dominated by the dust component so that the properties of the dust events can be further studied.

Flynn, Connor

149

Radioactivity of Dust  

Science Journals Connector (OSTI)

... it would be interesting to investigate in the same way the behaviour of atoms of radon and its disintegration products contained in air. The dust from air containing 1-5 ... . The dust from air containing 1-5 X 10 u curie/c.c. of radon was deposited in the form of a dust spot (Fig. 1) on a ...

Č. JECH

1949-04-09T23:59:59.000Z

150

Research on Characteristic Parameters of Coal-dust Explosion  

Science Journals Connector (OSTI)

The parameters of explosive characteristics of the coal-dust are assessed systematically with the test device of minimum ignition temperature of dust clouds and 20L sphere explosion test units. The minimum ignition temperature of dust is a main safety index when handling combustible dusts in industrial production, and while hazard evaluation, the maximum explosion pressure and the explosion index are key parameters. Five kinds of coal-dust with different particle diameters were tested in order to determine the temperature sensitivity and the ferocity under the given conditions, which can be used as the criteria to classify dust explosion hazards. The experiment results indicate that the minimum ignition temperature of coal-dust cloud reduces with the decrease of particle diameter under temperature of (293±5) K and powder spraying pressure of 0.08MPa, and when the particle size reduces to (25-48) ?m, the minimum ignition temperature is between (793-803)K; Besides that, the results can also show that minimum explosive concentration of coal-dust cloud is between 20 gám-3 and 30 gám-3under temperature of (293±5) K, powder spraying pressure of 2MPa and ignition energy of 10kJ, the maximum explosion pressure is 0.45MPa and the maximum explosion index is 11.14 MPaámás-1, which classifies coal-dust explosion hazards to Level I. The conclusions drawn from the experimental results are of great significance to the safe application of these combustible substances.

Weiguo Cao; Liyuan Huang; Jianxin Zhang; Sen Xu; Shanshan Qiu; Feng Pan

2012-01-01T23:59:59.000Z

151

Mean-field approach in the multi-component gas of interacting particles applied to relativistic heavy-ion collisions  

E-Print Network (OSTI)

Generalized mean-field approach for thermodynamic description of relativistic single- and multi-component gas in the grand canonical ensemble is formulated. In the framework of the proposed approach different phenomenological excluded-volume procedures are presented and compared to the existing ones. The mean-field approach is then used to effectively include hard-core repulsion in hadron-resonance gas model for description of chemical freeze-out in heavy-ion collisions. We calculate the collision energy dependence of several quantities for different values of hard-core hadron radius and for different excluded-volume procedures such as van der Waals and Carnahan-Starling models. It is shown that a choice of the excluded-volume model becomes important for large particle densities, and for large enough values of hadron radii ($r\\gtrsim0.9$ fm) there can be a sizable difference between different excluded-volume procedures used to describe the chemical freeze-out in heavy-ion collisions. For the smaller and more commonly used values of hard-core hadron radii ($r\\lesssim0.5$ fm) the van der Waals excluded-volume procedure is shown to be sufficient.

D. Anchishkin; V. Vovchenko

2015-01-23T23:59:59.000Z

152

Stabilization of the Shear Instability in a Dust Layer of a Protoplanetary Disk and Possible Formation of Planetesimals due to Gravitational Fragmentation of the Dust Layer  

E-Print Network (OSTI)

We show that the planetesimal formation due to the gravitational fragmentation of a dust layer in a protoplanetary disk is possible. The dust density distribution in the dust layer would approach the constant Richardson number distribution due to the dust stirring by the shear instability and dust settling. We perform the analysis of the shear instability of dust layer in a protoplanetary disk with the constant Richardson number density distribution. Our study revealed that this distribution is stable against the shear instability even if the dust density at the midplane reaches the critical density of the gravitational instability, and the planetesimal formation through the gravitational fragmentation of the dust layer can occur even for the dust to gas surface density ratio with the solar composition.

Naoki Ishitsu; Minoru Sekiya

2004-06-02T23:59:59.000Z

153

He Puff System For Dust Detector Upgrade  

SciTech Connect

Local detection of surface dust is needed for the safe operation of next-step magnetic fusion devices such as ITER. An electrostatic dust detector, based on a 5 cm x 5 cm grid of interlocking circuit traces biased to 50 V, has been developed to detect dust on remote surfaces and was successfully tested for the first time on the National Spherical Torus Experiment (NSTX). We report on a helium puff system that clears residual dust from this detector and any incident debris or fibers that might cause a permanent short circuit. The entire surface of the detector was cleared of carbon particles by two consecutive helium puffs delivered by three nozzles of 0.45 mm inside diameter. The optimal configuration was found to be with the nozzles at an angle of 30o with respect to the surface of the detector and a helium backing pressure of 6 bar. __________________________________________________

B. Rais, C.H. Skinner A.L. Roquemore

2010-10-01T23:59:59.000Z

154

HIGH FIDELITY STUDIES OF INTERSTELLAR DUST ANALOGUE IMPACTS IN STARDUST  

E-Print Network (OSTI)

HIGH FIDELITY STUDIES OF INTERSTELLAR DUST ANALOGUE IMPACTS IN STARDUST AEROGEL AND FOILS F://www.ssl.berkeley.edu/~westphal/ISPE/. In 2000 and 2002 the Stardust Mission exposed aerogel collector panels for a total of about 200 days/s] interstellar dust (ISD) analogues onto Stardust aerogel and foil flight spares. Particle impact speeds up to 50

155

The Dust Accelerator Facility of the Colorado Center for Lunar Dust and Atmospheric Studies  

SciTech Connect

The NASA Lunar Institute's Colorado Center for Lunar Dust and Atmospheric Studies has recently completed the construction of a new experimental facility to study hypervelocity dust impacts. The installation includes a 3 MV Pelletron, accelerating small particles in the size range of 0.1 to few microns to velocities in the range of 1 to 100 km/s. Here we report the capabilities of our facility, and the results of our first experiments.

Horanyi, M.; Colette, A.; Drake, K.; Gruen, E.; Kempf, S.; Munsat, T.; Robertson, S.; Shu, A.; Sternovsky, Z.; Wang, X. [NASA Lunar Science Institute Colorado Center for Lunar Dust and Atmospheric Studies University of Colorado, Boulder, CO, 80309 (United States)

2011-11-29T23:59:59.000Z

156

Karl G. Jansky Very Large Array observations of cold dust and molecular gas in starbursting quasar host galaxies at z ~ 4.5  

E-Print Network (OSTI)

-arcsecond imaging of this cold molecular gas in these targets would be complemented by higher resolution imaging of the (rest-frame) FIR continuum and [CII] line emission with ALMA in order to infer the ionizing radiation field and gas density on kpc scales. 6... code 13A-012). This paper makes use of the following ALMA data: ADS/JAO.ALMA#2011.0.00006.SV. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada) and NSC and ASIAA (Taiwan...

Wagg, J.; Carilli, C. L.; Aravena, M.; Cox, P.; Lentati, L.; Maiolino, R.; McMahon, R. G.; Riechers, D.; Walter, F.; Andreani, P.; Hills, R.; Wolfe, A.

2014-02-18T23:59:59.000Z

157

Dust density effect on complex plasma decay L. Couedel a,b, A.A. Samarian a  

E-Print Network (OSTI)

and supported by comparison to existing experimental data. Key words: Complex plasma, dust, afterglow, decay (PECVD, etching, fusion reactor,etc). The dust particles are charged due to their interactions, the dust particles can be either grown directly in the plasma chamber (by sputtering [6,7] or using

Paris-Sud XI, Université de

158

The flow of interstellar dust through the solar system: the role of dust charging  

SciTech Connect

Interstellar dust can enter the solar system through the relative motion of the Sun with respect to the Local Interstellar Cloud. The trajectories of the dust through the solar system are not only influenced by gravitation and solar radiation pressure forces, but also by the Lorentz forces due to the interaction of the interplanetary magnetic field with the charged dust particles. The interplanetary magnetic field changes on two major time scales: 25 days (solar rotation frequency) and 22 years (solar cycle). The short-term variability averages out for regions that are not too close (>{approx}2 AU) to the Sun. This interplanetary magnetic field variability causes a time-variability in the interstellar dust densities, that is correlated to the solar cycle.In this work we characterize the flow of interstellar dust through the solar system using simulations of the dust trajectories. We start from the simple case without Lorentz forces, and expand to the full simulation. We pay attention to the different ways of modeling the interplanetary magnetic field, and discuss the influence of the dust parameters on the resulting flow patterns. We also discuss the possibilities of using this modeling for prediction of dust fluxes for different space missions or planets, and we pay attention to where simplified models are justified, and where or when a full simulation, including all forces is necessary. One of the aims of this work is to understand measurements of spacecraft like Ulysses, Cassini and Stardust.

Sterken, V. J. [MPIK, Saupfercheckweg 1, D-69117 Heidelberg (Germany); TU Braunschweig, IGEP, Mendelssohnstr. 3, D-38106 Braunschweig (Germany); Altobelli, N.; Schwehm, G. [ESA-ESAC - P.O. Box 78, E-28691 Villanueva de la Canada, Madrid (Spain); Kempf, S. [LASP, University of Colorado, 1234 Innovation Dr, Boulder, CO, 80303-7814 (United States); TU Braunschweig, IGEP, Mendelssohnstr. 3, D-38106 Braunschweig (Germany); Srama, R. [MPIK, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Universitaet Stuttgart, IRS, Pfaffenwaldring 31, D-70569 Stuttgart (Germany); Strub, P. [MPS, Max-Planck-Strasse 2, D-37191 Katlenburg-Lindau (Germany); Gruen, E. [MPIK, Saupfercheckweg 1, D-69117 Heidelberg (Germany); LASP, University of Colorado, 1234 Innovation Dr, Boulder, CO, 80303-7814 (United States)

2011-11-29T23:59:59.000Z

159

Dust size distribution and concentrations with cottonseed oil mills  

E-Print Network (OSTI)

-VOLUME SAMPLES FOR P. S. D OF PARTICLES & 100 um DIAMETER (MMD) ANALYSIS OF VARIANCE ON HIGH-VOLUME SAMPLES FOR P. S. D. OF PARTICLES & 100 um DIAMETER (og) MULTIPLE RANGE TEST FOR MEAN VALUES OF MMD BY AREA MULTIPLE RANGE TEST OF MMD BY MILL PARTICLE SIZE... TEST OF AREA DUST CONCENTRATIONS = 15 Pm IN DIAMETER MULTIPLE RANGE TEST OF MILL DUST CONCENTRATIONS & 15 um IN DIAMETER ANALYSIS OF VARIANCE ON PARTICLE SIZING HEAD SAMPLES OF CONCENTRATIONS FOR PARTICLES & 100 IJBI DIAMETER . . . . 47 47 54...

Wiederhold, Lee Roy

2012-06-07T23:59:59.000Z

160

Apparatus to collect, classify, concentrate, and characterize gas-borne particles  

DOE Patents (OSTI)

An aerosol lab-on-a-chip (ALOC) integrates one or more of a variety of aerosol collection, classification, concentration (enrichment), and characterization processes onto a single substrate or layered stack of such substrates. By taking advantage of modern micro-machining capabilities, an entire suite of discrete laboratory aerosol handling and characterization techniques can be combined in a single portable device that can provide a wealth of data on the aerosol being sampled. The ALOC offers parallel characterization techniques and close proximity of the various characterization modules helps ensure that the same aerosol is available to all devices (dramatically reducing sampling and transport errors). Micro-machine fabrication of the ALOC significantly reduces unit costs relative to existing technology, and enables the fabrication of small, portable ALOC devices, as well as the potential for rugged design to allow operation in harsh environments. Miniaturization also offers the potential of working with smaller particle sizes and lower pressure drops (leading to reduction of power consumption).

Rader, Daniel J. (Albuquerque, NM); Torczynski, John R. (Albuquerque, NM); Wally, Karl (Lafayette, CA); Brockmann, John E. (Albuquerque, NM)

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Comparison of the limulus amebocyte lysate test and gas chromatography-mass spectrometry for measuring lipopolysaccharides (endotoxins) in airborne dust from poultry-processing industries.  

Science Journals Connector (OSTI)

...by using two-dimensional gas chromatography...alternative approach to measuring LPS is based on...performed with two-dimensional GC with electron-capture...3-hydroxy fatty acid standards 3-hydroxynonanoic...C, that of the interface between the GC...in the MS system standard software was used...

A Sonesson; L Larsson; A Schütz; L Hagmar; T Hallberg

1990-05-01T23:59:59.000Z

162

80From Dust Grains to Dust Balls A cosmic dust grain about 0.1mm across captured by a  

E-Print Network (OSTI)

-altitude aircraft. Probably debris from a passing comet Planets are built in several stages. The first Problem 2 ­Answer: The change in the mass, dM, occurs as a quantity of dust grains land on the surface in the interstellar gas, times the speed of the grains landing on the surface. This leads to m x N x V where m

163

Modeling Dust Jets And Shells From Comet Hale-Bopp  

Science Journals Connector (OSTI)

Persistent jet and shell structures from comet Hale-Bopp showing gradual changes in the shapes ... declination. Lower limits on the dust and gas production rates at various epochs are presented.

R. Vasundhara; Pavan Chakraborty; Andreas Hänel; Erwin Heiser

164

Magnetic signature of indoor air pollution: Household dust study  

Science Journals Connector (OSTI)

The combination of magnetic and geochemical methods was used to determine the mineralogy, grain size and domain structure of magnetic particles in indoor dust collected in 195 sites in Warsaw, Poland. Data sho...

Beata Górka-Kostrubiec; Maria Jele?ska; El?bieta Król

2014-12-01T23:59:59.000Z

165

Dust Studies in DIII-D and TEXTOR  

SciTech Connect

Studies of naturally occurring and artificially introduced carbon dust are conducted in DIII-D and TEXTOR. In DIII-D, dust does not present operational concerns except immediately after entry vents. Energetic plasma disruptions produce significant amounts of dust. However, dust production by disruptions alone is insufficient to account for the estimated in-vessel dust inventory in DIII-D. Submicron sized dust is routinely observed using Mie scattering from a Nd:Yag laser. The source is strongly correlated with the presence of Type I edge localized modes (ELMs). Larger size (0.005-1 mm diameter) dust is observed by optical imaging, showing elevated dust levels after entry vents. Inverse dependence of the dust velocity on the inferred dust size is found from the imaging data. Migration of pre-characterized carbon dust is studied in DIII-D and TEXTOR by injecting micron-size dust in plasma discharges. In DIII-D, a sample holder filled with {approx}30 mg of dust is introduced in the lower divertor and exposed to high-power ELMing H-mode discharges with strike points swept across the divertor floor. After a brief exposure ({approx}0.1 s) at the outer strike point, part of the dust is injected into the plasma, raising the core carbon density by a factor of 2-3 and resulting in a twofold increase of the radiated power. Individual dust particles are observed moving at velocities of 10-100 m/s, predominantly in the toroidal direction, consistent with the drag force from the deuteron flow and in agreement with modeling by the 3D DustT code. In TEXTOR, instrumented dust holders with 1-45 mg of dust are exposed in the scrape-off layer 0-2 cm radially outside of the last closed flux surface in discharges heated with neutral beam injection (NBI) power of 1.4 MW. Dust is launched either in the beginning of a discharge or at the initiation of NBI, preferentially in a direction perpendicular to the toroidal magnetic field. At the given configuration of the launch, the dust did not penetrate the core plasma and only moderately perturbed the edge plasma, as evidenced by an increase of the edge carbon content.

Rudakov, D; Litnovsky, A; West, W; Yu, J; Boedo, J; Bray, B; Brezinsek, S; Brooks, N; Fenstermacher, M; Groth, M; Hollmann, E; Huber, A; Hyatt, A; Krasheninnikov, S; Lasnier, C; Moyer, R; Pigarov, A; Philipps, V; Pospieszezyk, A; Smirnov, R; Sharpe, J; Solomon, W; Watkins, J; Wong, C

2008-10-14T23:59:59.000Z

166

Dust accelerators and their applications in high-temperature plasmas  

SciTech Connect

The perennial presence of dust in high-temperature plasma and fusion devices has been firmly established. Dust inventory must be controlled, in particular in the next-generation steady-state fusion machines like ITER, as it can pose significant safety hazards and potentially interfere with fusion energy production. Much effort has been devoted to gening rid of the dust nuisance. We have recognized a number of dust-accelerators applications in magnetic fusion, including in plasma diagnostics, in studying dust-plasma interactions, and more recently in edge localized mode (ELM)'s pacing. With the applications in mind, we will compare various acceleration methods, including electrostatic, gas-drag, and plasma-drag acceleration. We will also describe laboratory experiments and results on dust acceleration.

Wang, Zhehui [Los Alamos National Laboratory; Ticos, Catakin M [NILPRP, ROMANIA

2010-01-01T23:59:59.000Z

167

Dust resuspension as a contaminant source and transport pathway  

SciTech Connect

Numerous environmental contaminants sorb to dust particles or exist as particles, including metals, hydrophobic organic compounds, asbestos, pollens, and microbial pathogens. Wind resuspension of dust and other particulate matter provides a dust source for the atmosphere and a contaminant transport pathway. Not only do these materials pose a risk to human health, but also, resuspended dust particles are believed to play a role in global climate change and chemical reactions in the atmosphere. The conditions under which contaminated sites are vulnerable to wind resuspension are not generally known, as the basic physics of the problem are poorly understood. Field data show tremendous variability. Conventional dust flux models assume that dust resuspension occurs only for high winds and then only temporarily, with a transient dust flux occurring only when the bed is first exposed to the high wind. The surface is then assumed to stabilize such that no further dust moves until the surface is disturbed or a higher wind occurs. Recent wind tunnel experiments demonstrate that surfaces yield continuous steady dust fluxes under steady wind conditions well beyond the initial high transient flux, even when no erosion is visible and the velocity is below the predicted threshold velocity for movement. This average steady-state dust flux increases with average wind speed. Ongoing work is investigating the influence of air relative humidity on these processes. Contaminant resuspension models capture trends only and fail to predict sporadic high flux events that may control doses. Successful modeling of contaminant resuspension will depend on development of better dust flux predictions. Risk analyses require better predictive modeling, necessitating a deeper understanding of the underlying phenomena.

Loosmore, G.A,; Hunt, J.R.

1999-07-01T23:59:59.000Z

168

HD/H2 as a probe of the roles of gas, dust, light, metallicity and cosmic rays in promoting the growth of molecular hydrogen in the diffuse interstellar medium  

E-Print Network (OSTI)

We modelled recent observations of UV absorption of HD and \\HH\\ in the Milky Way and toward damped/sub-damped Lyman alpha systems at z=0.18 and z $>$ 1.7. N(HD)/N(\\HH) ratios reflect the separate self-shieldings of HD and \\HH\\ and the coupling introduced by deuteration chemistry. Locally, observations are explained by diffuse molecular gas with $ 16 \\pccc \\la$ n(H) $\\la 128 \\pccc $ if the cosmic-ray ionization rate per H-nucleus \\zetaH $= 2\\times 10^{-16}\\ps$ as inferred from \\H3\\p\\ and OH\\p. The dominant influence on N(HD)/N(\\HH) is the cosmic-ray ionization rate with a much weaker downward dependence on n(H) at Solar metallicity, but dust-extinction can drive N(HD) higher as with N(\\HH). At z $>$ 1.7, N(HD) is comparable to the Galaxy but with 10x smaller N(\\HH) and somewhat smaller N(\\HH)/N(H I). Comparison of our Galaxy and the Magellanic Clouds shows that smaller \\HH/H is expected at sub-Solar metallicity and we show by modelling that HD/\\HH\\ increases with density at low metallicity, opposite to the Mil...

Liszt, H S

2014-01-01T23:59:59.000Z

169

Laboratory Measurements of Contact Freezing by Dust and Bacteria at Temperatures of Mixed-Phase Clouds  

Science Journals Connector (OSTI)

Laboratory measurements of freezing by aerosol particles in contact mode are presented. The fraction of particles catalyzing freezing is quantified for three mineral dusts and three strains of bacteria. This is the most comprehensive such dataset ...

Joseph Niehaus; Jennifer G. Becker; Alexander Kostinski; Will Cantrell

2014-10-01T23:59:59.000Z

170

3 MV hypervelocity dust accelerator at the Colorado Center for Lunar Dust and Atmospheric Studies  

SciTech Connect

A hypervelocity dust accelerator for studying micrometeorite impacts has been constructed at the Colorado Center for Lunar Dust and Atmospheric Studies (CCLDAS) at the University of Colorado. Based on the Max-Planck-Instituet fuer Kernphysik (MPI-K) accelerator, this accelerator is capable of emitting single particles of a specific mass and velocity selected by the user. The accelerator consists of a 3 MV Pelletron generator with a dust source, four image charge pickup detectors, and two interchangeable target chambers: a large high-vacuum test bed and an ultra-high vacuum impact study chamber. The large test bed is a 1.2 m diameter, 1.5 m long cylindrical vacuum chamber capable of pressures as low as 10{sup -7} torr while the ultra-high vacuum chamber is a 0.75 m diameter, 1.1 m long chamber capable of pressures as low as 10{sup -10} torr. Using iron dust of up to 2 microns in diameter, final velocities have been measured up to 52 km/s. The spread of the dust particles and the effect of electrostatic focusing have been measured using a long exposure CCD and a quartz target. Furthermore, a new technique of particle selection is being developed using real time digital filtering techniques. Signals are digitized and then cross-correlated with a shaped filter, resulting in a suppressed noise floor. Improvements over the MPI-K design, which include a higher operating voltage and digital filtering for detection, increase the available parameter space of dust emitted by the accelerator. The CCLDAS dust facility is a user facility open to the scientific community to assist with instrument calibrations and experiments.

Shu, Anthony; Horanyi, Mihaly; Kempf, Sascha; Thomas, Evan [Colorado Center for Lunar Dust and Atmospheric Studies, Boulder, Colorado 80303 (United States); Department of Physics, University of Colorado, Boulder, Colorado 80309 (United States); Laboratory for Atmospheric and Space Physics, 1234 Innovation Drive, Boulder, Colorado 80303 (United States); Collette, Andrew; Drake, Keith; Northway, Paige [Colorado Center for Lunar Dust and Atmospheric Studies, Boulder, Colorado 80303 (United States); Laboratory for Atmospheric and Space Physics, 1234 Innovation Drive, Boulder, Colorado 80303 (United States); Gruen, Eberhard [Colorado Center for Lunar Dust and Atmospheric Studies, Boulder, Colorado 80303 (United States); MPI fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Mocker, Anna [Colorado Center for Lunar Dust and Atmospheric Studies, Boulder, Colorado 80303 (United States); MPI fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); IRS, Universitaet Stuttgart, Pfaffenwaldring 31, D-70569 Stuttgart (Germany); Munsat, Tobin [Colorado Center for Lunar Dust and Atmospheric Studies, Boulder, Colorado 80303 (United States); Department of Physics, University of Colorado, Boulder, Colorado 80309 (United States); Srama, Ralf [MPI fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); IRS, Universitaet Stuttgart, Pfaffenwaldring 31, D-70569 Stuttgart (Germany); and others

2012-07-15T23:59:59.000Z

171

LOOKING THROUGH THE HIPPO: NUCLEUS AND DUST IN COMET 2P/ENCKE David Jewitt  

E-Print Network (OSTI)

´ndez et al. 2000). Compared with recent, bright long-period com- ets such as C/Hale-Bopp and C (see also Gehrz & Ney 1992), meaning that the comet is gas-rich and dust-poor. The latter conclusion cannot liter- ally be true, however, since strong, long-wavelength thermal emission indicates a dust/gas

Jewitt, David C.

172

ON THE INITIAL MASS FUNCTION OF LOW-METALLICITY STARS: THE IMPORTANCE OF DUST COOLING  

SciTech Connect

The first stars to form in the universe are believed to have distribution of masses biased toward massive stars. This contrasts with the present-day initial mass function, which has a predominance of stars with masses lower than 1 M{sub Sun }. Therefore, the mode of star formation must have changed as the universe evolved. Such a transition is attributed to a more efficient cooling provided by increasing metallicity. Especially dust cooling can overcome the compressional heating, which lowers the gas temperature thus increasing its instability to fragmentation. The purpose of this paper is to verify if dust cooling can efficiently cool the gas, and enhance the fragmentation of gas clouds at the early stages of the universe. To confirm that, we calculate a set of hydrodynamic simulations that include sink particles, which represent contracting protostars. The thermal evolution of the gas during the collapse is followed by making use of a primordial chemical network and also a recipe for dust cooling. We model four clouds with different amounts of metals (10{sup -4}, 10{sup -5}, 10-6 Z{sub Sun }, and 0), and analyze how this property affect the fragmentation of star-forming clouds. We find evidence for fragmentation in all four cases, and hence conclude that there is no critical metallicity below which fragmentation is impossible. Nevertheless, there is a clear change in the behavior of the clouds at Z {approx}< 10{sup -5} Z{sub Sun }, caused by the fact that at this metallicity, fragmentation takes longer to occur than accretion, leading to a flat mass function at lower metallicities.

Dopcke, Gustavo [Member of the International Max Planck Research School for Astronomy and Cosmic Physics at the University of Heidelberg, IMPRS-HD, Germany. (Germany)] [Member of the International Max Planck Research School for Astronomy and Cosmic Physics at the University of Heidelberg, IMPRS-HD, Germany. (Germany); Glover, Simon C. O.; Clark, Paul C.; Klessen, Ralf S., E-mail: gustavo@uni-hd.de [Zentrum fuer Astronomie, Institut fuer Theoretische Astrophysik, Universitaet Heidelberg, Albert-Ueberle-Str. 2, D-69120 Heidelberg (Germany)

2013-04-01T23:59:59.000Z

173

Benchmarking of the MIT High Temperature Gas-cooled Reactor TRISO-coated particle fuel performance model  

E-Print Network (OSTI)

MIT has developed a Coated Particle Fuel Performance Model to study the behavior of TRISO nuclear fuels. The code, TIMCOAT, is designed to assess the mechanical and chemical condition of populations of coated particles and ...

Stawicki, Michael A

2006-01-01T23:59:59.000Z

174

Fuel Property, Emission Test, and Operability Results from a Fleet of Class 6 Vehicles Operating on Gas-to-Liquid Fuel and Catalyzed Diesel Particle Filters  

SciTech Connect

A fleet of six 2001 International Class 6 trucks operating in southern California was selected for an operability and emissions study using gas-to-liquid (GTL) fuel and catalyzed diesel particle filters (CDPF). Three vehicles were fueled with CARB specification diesel fuel and no emission control devices (current technology), and three vehicles were fueled with GTL fuel and retrofit with Johnson Matthey's CCRT diesel particulate filter. No engine modifications were made.

Alleman, T. L.; Eudy, L.; Miyasato, M.; Oshinuga, A.; Allison, S.; Corcoran, T.; Chatterjee, S.; Jacobs, T.; Cherrillo, R. A.; Clark, R.; Virrels, I.; Nine, R.; Wayne, S.; Lansing, R.

2005-11-01T23:59:59.000Z

175

Contamination by Dust Particles and Intensive Desiccation  

Science Journals Connector (OSTI)

... the area of the quasi-porous internal surface of glass that has been cleaned and roughened by cleaning solution. Again, the fusion process may engulf and incorporate beneath a relatively ...

ALAN W. C. MENZIES

1930-03-22T23:59:59.000Z

176

Dust Deserves More than the Brush-Off | Department of Energy  

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

Dust Deserves More than the Brush-Off Dust Deserves More than the Brush-Off Dust Deserves More than the Brush-Off July 6, 2012 - 10:35am Addthis The dust particles act as a "heat pump" drawing heat from the sun and surface, and attracting moisture from the Gulf of California and the Gulf of Mexico. Without dust, rainfall would be up to 40 percent less over Arizona, New Mexico and Texas. | Creative Commons photo by Jared The dust particles act as a "heat pump" drawing heat from the sun and surface, and attracting moisture from the Gulf of California and the Gulf of Mexico. Without dust, rainfall would be up to 40 percent less over Arizona, New Mexico and Texas. | Creative Commons photo by Jared

177

Cotton Gin Dust Explosibility Determinations  

E-Print Network (OSTI)

personnel listed dust found in cotton gins, or gin dust, fueled two explosions in the past. OSHA is required by law to regulate facilities handling explosible dusts to provide a safe working environment for employees. The dust handling facilities must test...

Vanderlick, Francis Jerome

2014-01-06T23:59:59.000Z

178

Radioactive Dust from Nuclear Detonations  

Science Journals Connector (OSTI)

...than the dose received from natural radioactivity in a period of...radioactive particles. The natural radioactivity of the atmosphere...curies/liter. This radioactive gas is present in equilibrium with...With an approximation of the natural radiation dose to the lung as...

Merril Eisenbud; John H. Harley

1953-02-13T23:59:59.000Z

179

Flue gas conditioning for improved particle collection in electrostatic precipitators. Quarterly technical report, October 1--December 31, 1993  

SciTech Connect

The initial pilot-scale testing of two additives was completed at CONSOL`s research coal combustor. The results and conclusions from this test series and subsequent analysis of the data are presented in this report. Table 1 summarizes the conditions tested. During the tests, the research combustor was firing a medium-sulfur coal. The combustor had recently been retrofitted with low-NOx burners for a DOE Clean Coal test program. Operation of the low-NOx burners required a reduced flow rate in the combustor, resulting in lower flow and velocity in the ESP. A comprehensive baseline condition was tested, followed by initial screening runs for several additives. It was discovered that the flyash exhibited properties characteristic of a high-resistivity ash. In-situ measurements at the ESP inlet confirmed that the resistivity was in the 10{sup 10} -- 10{sup 12} ohm-cm range. In addition, the ESP plate rappers were not able to remove ash buildup on the first section during normal operation. Power off rapping was periodically required to fully clean the plates; this is a clear indication of high-resistivity conditions. Since the major benefit of ESP additives will be to reduce reentrainment at low to midrange resistivity, this operating condition was undesirable for performance testing. It was decided to continue the program with SO{sub 3} conditioning of the flue gas to reduce particle resistivity. It was also decided to operate with two rather than three electrical fields energized. By reducing the ESP collection area, it was hoped that it would be easier to measure changes in ESP performance and to see an immediate indication of the effectiveness Of SO{sub 3} conditioning. The ESP was reconfigured with two electrical sections energized and SO{sub 3} conditioning at a rate of approximately 20 ppM. An additional baseline was run, followed by extended tests with two additives referred to in this report as Additive ``C`` and Additive ``D.``

Durham, M.D.; Baldrey, K.E.

1994-01-12T23:59:59.000Z

180

Particle impact damping: influence of material and size  

E-Print Network (OSTI)

In this study, particle impact damping is measured for a cantilever beam with a particle-filled enclosure attached to its free end. Many particle materials are tested: lead spheres, steel spheres, glass spheres, tungsten carbide pellets, lead dust...

Marhadi, Kun Saptohartyadi

2005-02-17T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Design of a new cotton dust sampler  

E-Print Network (OSTI)

with the development of a penetration curve which resulted in a cutpoint of 10. 1 pm with a slope of 1. 31. The operating characteristics of the cyclone cotton dust sampler are: a sampling rate of 50 liters per minute, collection of particulate on top of a... SAMPLER AT VARIOUS INLET CONFIGURATIONS AND SAMPLING RATES Page 40 PENETRATION VALUES OF PARTICLE DIAMETERS INVESTI- GATED AT THREE DIFFERENT HEIGHTS ABOVE THE INLET OF THE CYCLONE SAMPLER PENETRATION VALUES USED TO DETERMINE CYCLONE SAMPLER...

Hickman, Phillip Dean

2012-06-07T23:59:59.000Z

182

Dust acoustic solitary and shock excitations in a Thomas-Fermi magnetoplasma  

SciTech Connect

The linear and nonlinear properties of dust-acoustic waves are investigated in a collisionless Thomas-Fermi magnetoplasma, whose constituents are electrons, ions, and negatively charged dust particles. At dust time scale, the electron and ion number densities follow the Thomas-Fermi distribution, whereas the dust component is described by the classical fluid equations. A linear dispersion relation is analyzed to show that the wave frequencies associated with the upper and lower modes are enhanced with the variation of dust concentration. The effect of the latter is seen more strongly on the upper mode as compared to the lower mode. For nonlinear analysis, we obtain magnetized Korteweg-de Vries (KdV) and Zakharov-Kuznetsov (ZK) equations involving the dust-acoustic solitary waves in the framework of reductive perturbation technique. Furthermore, the shock wave excitations are also studied by allowing dissipation effects in the model, leading to the Korteweg-de Vries-Burgers (KdVB) and ZKB equations. The analysis reveals that the dust-acoustic solitary and shock excitations in a Thomas-Fermi plasma are strongly influenced by the plasma parameters, e.g., dust concentration, dust temperature, obliqueness, magnetic field strength, and dust fluid viscosity. The present results should be important for understanding the solitary and shock excitations in the environments of white dwarfs or supernova, where dust particles can exist.

Rahim, Z.; Qamar, A. [Institute of Physics and Electronics, University of Peshawar, Peshawar 25000 (Pakistan); National Center for Physics (NCP) at QAU Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Ali, S. [National Center for Physics (NCP) at QAU Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan)

2014-07-15T23:59:59.000Z

183

Determining inert content in coal dust/rock dust mixture  

DOE Patents (OSTI)

A method and apparatus for determining the inert content of a coal dust and rock dust mixture uses a transparent window pressed against the mixture. An infrared light beam is directed through the window such that a portion of the infrared light beam is reflected from the mixture. The concentration of the reflected light is detected and a signal indicative of the reflected light is generated. A normalized value for the generated signal is determined according to the relationship .phi.=(log i.sub.c `log i.sub.co) / (log i.sub.c100 -log i.sub.co) where i.sub.co =measured signal at 0% rock dust i.sub.c100 =measured signal at 100% rock dust i.sub.c =measured signal of the mixture. This normalized value is then correlated to a predetermined relationship of .phi. to rock dust percentage to determine the rock dust content of the mixture. The rock dust content is displayed where the percentage is between 30 and 100%, and an indication of out-of-range is displayed where the rock dust percent is less than 30%. Preferably, the rock dust percentage (RD%) is calculated from the predetermined relationship RD%=100+30 log .phi.. where the dust mixture initially includes moisture, the dust mixture is dried before measuring by use of 8 to 12 mesh molecular-sieves which are shaken with the dust mixture and subsequently screened from the dust mixture.

Sapko, Michael J. (Finleyville, PA); Ward, Jr., Jack A. (Oakmont, PA)

1989-01-01T23:59:59.000Z

184

A Comparison of Magnetic Resonance, X-ray and Positron Emission Particle Tracking Measurements of a Single Jet of Gas Entering a Bed of Particles  

E-Print Network (OSTI)

resolution ~1.5 ms ~0.2 ms ~1 ms spatial resolution ~1 mm ~0.1 mm ~0.5 mm velocity yes no yes dispersion yes no yes granular temperature yes no yes scale (bed dia.) 50 mm 270 mm 750 mm 3 Image Analysis 3.1 MRI MR images were processed using... .R., McNeil, P. (1993) Positron emission particle tracking - a technique for studying flow within engineering equipment. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 326...

Pore, M.; Ong, G. H.; Boyce, C. M.; Materazzi, M.; Gargiuli, J.; Leadbeater, T.; Sederman, A. J.; Dennis, J. S.; Holland, D. J.; Ingram, A.; Lettieri, P.; Parker, D. J.

2014-01-01T23:59:59.000Z

185

Momentum, energy and scalar transport in polydisperse gas-solid flows using particle-resolved direct numerical simulations.  

E-Print Network (OSTI)

??Gas-solid flows are commonly encountered in Nature and in several industrial applications. Emerging carbon-neutral or carbon negative technologies such as chemical looping combustion and CO2… (more)

Tenneti, Sudheer

2013-01-01T23:59:59.000Z

186

In-line continuous sizing of biomass particles in gas-solid two-phase flow at a biomass-fired power plant  

Science Journals Connector (OSTI)

Gas-solid two-phase flows are widely seen in many industrial processes. A good exampleis the pneumatically conveyed pulverised fuel flow in the power generation industry. As a significant renewable fuel source biomass has been widely adopted in electrical power generation. The particle size distribution of pneumatically conveyed biomass correlates closely with combustion efficiency and pollutant emissions and should therefore be monitored on anin-line continuous basis. In this paper an integrated instrumentation system using both a piezoelectric sensorand anelectrostatic sensor arrayis proposed to measure the size distribution and flow velocity of biomass particles. A prototype system was tested on a 250mm bore pipe at a biomass-fired power plantand its performance has been evaluated under industrial conditions.

2014-01-01T23:59:59.000Z

187

Impact of natural gas fuel composition on criteria, toxic, and particle emissions from transit buses equipped with lean burn and stoichiometric engines  

Science Journals Connector (OSTI)

Abstract This study investigated the impacts of varying natural gas composition on the exhaust emissions from different technology transit buses. For this study, two CNG (compressed natural gas) buses equipped with lean burn combustion and \\{OCs\\} (oxidation catalysts), and one stoichiometric CNG bus equipped with a TWC (three-way catalyst) and EGR (exhaust gas recirculation) were tested on a chassis dynamometer over the CBD (Central Business District) cycle on six different gas blends each. The gases represented a range of compositions from gases with high levels of methane and correspondingly lower energy contents/WN (Wobbe number) to gases with higher levels of heavier hydrocarbons and correspondingly higher energy contents/WN. For the lean burn buses, gases with low methane contents exhibited higher \\{NOx\\} (nitrogen oxides) (19%–53%) and NMHC (non-methane hydrocarbon) (39%–102%) emissions, but lower emissions of THC (total hydrocarbon) (9%–24%), CH4 (methane) (23%–33%), and formaldehyde emissions (14%–45%). The stoichiometric engine bus with a TWC showed significantly reduced \\{NOx\\} and THC emissions compared to the lean burn buses, but did show higher levels of CO (carbon monoxide) and NH3 (ammonia). PM (particulate matter) mass emissions did not show any fuel effects, while PN (particle number) emissions exhibited some reductions for the higher WN gases.

Maryam Hajbabaei; Georgios Karavalakis; Kent C. Johnson; Linda Lee; Thomas D. Durbin

2013-01-01T23:59:59.000Z

188

DUST-PLASMA INTERACTIONS  

SciTech Connect

The objective of our theoretical research under this grant over the past 3 years was to develop new understanding in a range of topics in the physics of dust-plasma interactions, with application to space and the laboratory. We conducted studies related to the physical properties of dust, waves and instabilities in both weakly coupled and strongly coupled dusty plasmas, and innovative possible applications. A major consideration in our choice of topics was to compare theory with experiments or observations, and to motivate new experiments, which we believe is important for developing this relatively new field. Our research is summarized, with reference to our list of journal publications.

Dr. M. Rosenberg

2010-01-05T23:59:59.000Z

189

Viable Algae in House Dust  

Science Journals Connector (OSTI)

... two culture media: Bristol8 and modified Chu No. 10 (ref. 9). Viable algae were cultured from all the dust samples taken from forty -one homes. In these ... 1). Samples from three commercial producers of house dust allergenic extract also revealed viable algae (Table 2). In general, the algal organisms found in house dust used in ...

I. LEONARD BERNSTEIN; ROBERT S. SAFFERMAN

1970-08-22T23:59:59.000Z

190

Dynamics of the electric current in an ideal electron gas: a sound mode inside the quasi-particles  

E-Print Network (OSTI)

We study the equation of motion for the Noether current in an electron gas within the framework of the Schwinger-Keldysh Closed-Time-Path formalism. The equation is shown to be highly non-linear and irreversible even for a non-interacting, ideal gas of electrons at non-zero density. We truncate the linearised equation of motion, written as the Laurent series in Fourier space, so that the resulting expressions are local in time, both at zero and at small finite temperatures. Furthermore, we show that the one-loop Coulomb interactions only alter the physical picture quantitatively, while preserving the characteristics of the dynamics that the electric current exhibits in the absence of interactions. As a result of the composite nature of the Noether current, composite sound waves are found to be the dominant IR collective excitations at length scales between the inverse Fermi momentum and the mean free path that would exist in an interacting electron gas. We also discuss the difference and the transition between the hydrodynamical regime of an ideal gas, defined in this work, and the hydrodynamical regime in phenomenological hydrodynamics, which is normally used for the description of interacting gases.

Sašo Grozdanov; Janos Polonyi

2015-01-26T23:59:59.000Z

191

Method of removing SO.sub.2, NO.sub.X and particles from gas mixtures using streamer corona  

DOE Patents (OSTI)

A method for converting sulfur dioxide and/or nitrogen oxide gases to acid mist and or particle aerosols is disclosed in which the gases are passed through a streamer corona discharge zone having electrodes of a wire-cylinder or wire-plate geometry.

Mizuno, Akira (Toyohashi, JP); Clements, Judson S. (Tallahassee, FL)

1987-01-01T23:59:59.000Z

192

Inside dust devils  

Science Journals Connector (OSTI)

......is added by random atmospheric surface eddies in the...surface. Wind speed Atmospheric vortices such as tornadoes, dust devils and water spouts are often recognized...internal wind speeds of atmospheric vortices and this is...test using a vortex generator Lunar and Planetary......

T J Ringrose

2005-10-01T23:59:59.000Z

193

Two evolutional paths of an axisymmetric gravitational instability in the dust layer of a protoplanetary disk  

E-Print Network (OSTI)

Nonlinear numerical simulations are performed to investigate the density evolution in the dust layer of a protoplanetary disk due to the gravitational instability and dust settling toward the midplane. We assume the region where the radial pressure gradient at equilibrium is negligible so that the shear-induced instability is avoided, and also restrict to an axisymmetric perturbation as a first step of nonlinear numerical simulations of the gravitational instability. We find that there are two different evolutional paths of the gravitational instability depending on the nondimensional gas friction time, which is defined as the product of the gas friction time and the Keplerian angular velocity. If the nondimensional gas friction time is equal to 0.01, the gravitational instability grows faster than dust settling. On the other hand, if the nondimensional gas friction time is equal to 0.1, dust aggregates settle sufficiently before the gravitational instability grows. In the latter case, an approximate analytical calculation reveals that dust settling is faster than the growth of the gravitational instability regardless of the dust density at the midplane. Thus, the dust layer becomes extremely thin and may reach a few tenth of the material density of the dust before the gravitational instability grows.

Fumiharu Yamoto; Minoru Sekiya

2006-05-08T23:59:59.000Z

194

Radon-222, CO, CH4 and Continental Dust over the Greenland and Norwegian Seas  

Science Journals Connector (OSTI)

... The experiment was undertaken to investigate the relationships between these parameters and air mass trajectories. Radon (222Rn)-a radioactive rare gas emanating essentially from large continental land areas-and dust ... removed by coagulation and fallout or washed out by rain or fog, although comparison of radon level and dust data may be helpful in tracing the trajectory and mixing of air ...

R. E. LARSON; R. A. LAMONTAGNE; P. E. WILKNISS; W. I. WITTMANN

1972-12-08T23:59:59.000Z

195

Evaluation of gas-liquid separation performance of natural gas filters  

Science Journals Connector (OSTI)

Fibrous filters are often used to remove contaminants including both dusts and liquid droplets from natural gas. This paper aims to evaluate the gas-liquid separation performance of three types of cartridge filte...

Baisong Li; Zhongli Ji; Xue Yang

2009-12-01T23:59:59.000Z

196

Preliminary design of dust lifting and transport in the martian General Circulation Model.  

E-Print Network (OSTI)

by the GCM When wind blows accross a surface covered by loose particles, kinetic energy is transferred Package 4 1 #12; Contents 1 Introduction 2 2 Dust lifting 3 2.1 Lifting by the general circulation winds . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.1.4 Implementation in the GCM. . . . . . . . . . . . . . . . . 6 2.2 Lifting by dust devils

Forget, François

197

Ultrafine PM Emissions from Natural Gas, Oxidation-Catalyst Diesel, and Particle-Trap Diesel Heavy-Duty Transit Buses  

Science Journals Connector (OSTI)

In urban areas, transit buses are a significant source of heavy-duty vehicle traffic, and many municipalities, including Los Angeles, Sacramento, Cleveland, and Atlanta, have recently modified their fleets to compressed natural gas (CNG) as the “clean” alternative to conventional uncontrolled diesel vehicles to meet increasingly strict particulate matter (PM) air quality regulations. ... ARB's mission is to promote and protect public health, welfare, and ecological resources through effective reduction of air pollutants while recognizing and considering effects on the economy. ...

Britt A. Holmén; Alberto Ayala

2002-11-05T23:59:59.000Z

198

Dynamics of the electric current in an ideal electron gas: a sound mode inside the quasi-particles  

E-Print Network (OSTI)

We study the equation of motion for the Noether current in an electron gas within the framework of the Schwinger-Keldysh Closed-Time-Path formalism. The equation is shown to be highly non-linear and irreversible even for a non-interacting, ideal gas of electrons at non-zero density. We truncate the linearised equation of motion, written as the Laurent series in Fourier space, so that the resulting expressions are local in time, both at zero and at small finite temperatures. Furthermore, we show that the one-loop Coulomb interactions only alter the physical picture quantitatively, while preserving the characteristics of the dynamics that the electric current exhibits in the absence of interactions. As a result of the composite nature of the Noether current, composite sound waves are found to be the dominant IR collective excitations at length scales between the inverse Fermi momentum and the mean free path that would exist in an interacting electron gas. We also discuss the difference and the transition betwee...

Grozdanov, Sašo

2015-01-01T23:59:59.000Z

199

Dust tracking techniques applied to the STARDUST facility: First results  

Science Journals Connector (OSTI)

Abstract An important issue related to future nuclear fusion reactors fueled with deuterium and tritium is the creation of large amounts of dust due to several mechanisms (disruptions, \\{ELMs\\} and VDEs). The dust size expected in nuclear fusion experiments (such as ITER) is in the order of microns (between 0.1 and 1000 ?m). Almost the total amount of this dust remains in the vacuum vessel (VV). This radiological dust can re-suspend in case of LOVA (loss of vacuum accident) and these phenomena can cause explosions and serious damages to the health of the operators and to the integrity of the device. The authors have developed a facility, STARDUST, in order to reproduce the thermo fluid-dynamic conditions comparable to those expected inside the VV of the next generation of experiments such as ITER in case of LOVA. The dust used inside the STARDUST facility presents particle sizes and physical characteristics comparable with those that created inside the VV of nuclear fusion experiments. In this facility an experimental campaign has been conducted with the purpose of tracking the dust re-suspended at low pressurization rates (comparable to those expected in case of LOVA in ITER and suggested by the General Safety and Security Report ITER-GSSR) using a fast camera with a frame rate from 1000 to 10,000 images per second. The velocity fields of the mobilized dust are derived from the imaging of a two-dimensional slice of the flow illuminated by optically adapted laser beam. The aim of this work is to demonstrate the possibility of dust tracking by means of image processing with the objective of determining the velocity field values of dust re-suspended during a LOVA.

A. Malizia; M. Camplani; M. Gelfusa; I. Lupelli; M. Richetta; L. Antonelli; F. Conetta; D. Scarpellini; M. Carestia; E. Peluso; C. Bellecci; L. Salgado; P. Gaudio

2014-01-01T23:59:59.000Z

200

E-Print Network 3.0 - anomalous dust emission Sample Search Results  

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

vs Infall? EAS Publications Series, Vol. ?, 2009 Summary: disks of galaxies: using the gas-to-dust ratio traced by the ratio of infrared emission to H I 21-cm... some time (Koo...

Note: This page contains sample records for the topic "dust particles gas" 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

Photographic observations of comet Hale-Bopp at the Pulkovo Observatory: The detection of dust envelopes  

Science Journals Connector (OSTI)

The photographic observations of comet Hale-Bopp with the 26-inch Pulkovo Observatory ... in March–April, 1998, revealed three hemispherical gas-dust envelopes and one spiral jet in...

Yu. N. Gnedin; A. A. Kiselev; T. P. Kiseleva; K. L. Maslennikov

2001-04-01T23:59:59.000Z

202

ITP Materials: Poster - Development of Materials Resistant to Metal Dusting Degradation  

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

metal dusting phenomenon metal dusting phenomenon in simulated process environments ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ ITP Materials, Sensors, and Automation, and Glass Project and Portfolio Review Meeting, June 21-24, Arlington, Virginia. K. Natesan, Z. Zeng, and D. L. Rink Energy Technology Division, Argonne National Laboratory, Argonne, Illinois, 60439 Introduction Metal dusting is a metal loss process that occurs in hot reactive gases The prerequisite for metal dusting is that carbon activity in the gas phase has to be >>1 Metal ends up as fine powder Pitting and crevice attack are common forms

203

Microsoft PowerPoint - 16_Sahara.dust.min.20070326.ppt [Compatibility...  

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

Area Convective Rain Stratiform Rain advection Saharan dusts act as ice forming nuclei to produce more, small size cloud ice particle, but unable to grow up to PR detectable ice...

204

Measurements of Saharan Dust in Convective Clouds over the Tropical Eastern Atlantic Ocean  

Science Journals Connector (OSTI)

Mineral dust particles have been shown to act as cloud condensation nuclei, and they are known to interact with developing tropical storms over the Atlantic downwind of the Sahara. Once present within liquid droplets, they have the potential to ...

Cynthia H. Twohy

205

Dust Masses, PAH Abundances, and Starlight Intensities in the SINGS Galaxy Sample  

E-Print Network (OSTI)

Physical dust models are presented for 65 galaxies in the SINGS survey that are strongly detected in the four IRAC bands and three MIPS bands. For each galaxy we estimate (1) the total dust mass, (2) the fraction of the dust mass contributed by PAHs, and (3) the intensity of the starlight heating the dust grains. We find that spiral galaxies have dust properties resembling the dust in the local region of the Milky Way, with similar dust-to-gas ratio, and similar PAH abundance. The observed SEDs, including galaxies with SCUBA photometry, can be reproduced by dust models that do not require "cold" (Tmedia of galaxies with A_O=12+log(O/H)>8.1, grains contain a substantial fraction of interstellar Mg, Si and Fe. Galaxies with A_O8.1 have a median q_PAH=3.55%. The derived dust masses favor a value X_CO approx 4e20 cm^{-2}(K kms)^{-1} for the CO to H_2 conversion factor. Except for some starbursting systems (Mrk33, Tolo89, NGC3049), dust in the diffuse ISM dominates the IR power.

B. T. Draine; D. A. Dale; G. Bendo; K. D. Gordon; J. D. T. Smith; L. Armus; C. W. Engelbracht; G. Helou; R. C. Kennicutt; A. Li; H. Roussel; F. Walter; D. Calzetti; J. Moustakas; E. J. Murphy; G. H. Rieke; C. Bot; D. J. Hollenbach; K. Sheth; H. I. Teplitz

2007-03-09T23:59:59.000Z

206

Uncertainty in Modeling Dust Mass Balance and Radiative Forcing from Size Parameterization  

SciTech Connect

This study examines the uncertainties in simulating mass balance and radiative forcing of mineral dust due to biases in the aerosol size parameterization. Simulations are conducted quasi-globally (180oW-180oE and 60oS-70oN) using the WRF24 Chem model with three different approaches to represent aerosol size distribution (8-bin, 4-bin, and 3-mode). The biases in the 3-mode or 4-bin approaches against a relatively more accurate 8-bin approach in simulating dust mass balance and radiative forcing are identified. Compared to the 8-bin approach, the 4-bin approach simulates similar but coarser size distributions of dust particles in the atmosphere, while the 3-mode pproach retains more fine dust particles but fewer coarse dust particles due to its prescribed og of each mode. Although the 3-mode approach yields up to 10 days longer dust mass lifetime over the remote oceanic regions than the 8-bin approach, the three size approaches produce similar dust mass lifetime (3.2 days to 3.5 days) on quasi-global average, reflecting that the global dust mass lifetime is mainly determined by the dust mass lifetime near the dust source regions. With the same global dust emission (~6000 Tg yr-1), the 8-bin approach produces a dust mass loading of 39 Tg, while the 4-bin and 3-mode approaches produce 3% (40.2 Tg) and 25% (49.1 Tg) higher dust mass loading, respectively. The difference in dust mass loading between the 8-bin approach and the 4-bin or 3-mode approaches has large spatial variations, with generally smaller relative difference (<10%) near the surface over the dust source regions. The three size approaches also result in significantly different dry and wet deposition fluxes and number concentrations of dust. The difference in dust aerosol optical depth (AOD) (a factor of 3) among the three size approaches is much larger than their difference (25%) in dust mass loading. Compared to the 8-bin approach, the 4-bin approach yields stronger dust absorptivity, while the 3-mode approach yields weaker dust absorptivity. Overall, on quasi-global average, the three size parameterizations result in a significant difference of a factor of 2~3 in dust surface cooling (-1.02~-2.87 W m-2) and atmospheric warming (0.39~0.96 W m-2) and in a tremendous difference of a factor of ~10 in dust TOA cooling (-0.24~-2.20 W m-2). An uncertainty of a factor of 2 is quantified in dust emission estimation due to the different size parameterizations. This study also highlights the uncertainties in modeling dust mass and number loading, deposition fluxes, and radiative forcing resulting from different size parameterizations, and motivates further investigation of the impact of size parameterizations on modeling dust impacts on air quality, climate, and ecosystem.

Zhao, Chun; Chen, Siyu; Leung, Lai-Yung R.; Qian, Yun; Kok, Jasper; Zaveri, Rahul A.; Huang, J.

2013-11-05T23:59:59.000Z

207

Evaluating chemical and physical properties of grain dust for use in an explosion hazard indicator  

E-Print Network (OSTI)

0, um P 30. 0 40. 0 50. 0 FIG. l Hlnimum explosive concentration as a function of particle diameter and distance between particles, the highest levels measured at transfer points. From studies at Texas AFM University, Parnell and 8arton (1979... ) found dust levels in wheat and grain sorghum from a terminal elevator vary from 1000 to 5000 grams of dust less than 100 um per metric ton of grain (2 to 10 pounds per ton). Levels of dust in grain sorghum samples collected by Parnell (1981...

Plemons, Dorothy Sue

2012-06-07T23:59:59.000Z

208

Dust time in quantum cosmology  

E-Print Network (OSTI)

We give a formulation of quantum cosmology with a pressureless dust and arbitrary additional matter fields. The dust provides a natural time gauge corresponding to a cosmic time, yielding a physical time independent Hamiltonian. The approach simplifies the analysis of both Wheeler-deWitt and loop quantum cosmology models, broadening the applicability of the latter.

Husain, Viqar

2013-01-01T23:59:59.000Z

209

Evaluation of Alternate Materials for Coated Particle Fuels for the Gas-Cooled Fast Reactor. Laboratory Directed Research and Development Program FY 2006 Final Report  

SciTech Connect

Candidate ceramic materials were studied to determine their suitability as Gas-Cooled Fast Reactor particle fuel coatings. The ceramics examined in this work were: TiC, TiN, ZrC, ZrN, AlN, and SiC. The studies focused on (i) chemical reactivity of the ceramics with fission products palladium and rhodium, (ii) the thermomechanical stresses that develop in the fuel coatings from a variety of causes during burnup, and (iii) the radiation resiliency of the materials. The chemical reactivity of TiC, TiN, ZrC, and ZrN with Pd and Rh were all found to be much lower than that of SiC. A number of important chemical behaviors were observed at the ceramic-metal interfaces, including the formation of specific intermetallic phases and a variation in reaction rates for the different ceramics investigated. Based on the data collected in this work, the nitride ceramics (TiN and ZrN) exhibit chemical behavior that is characterized by lower reaction rates with Pd and Rh than the carbides TiC and ZrC. The thermomechanical stresses in spherical fuel particle ceramic coatings were modeled using finite element analysis, and included contributions from differential thermal expansion, fission gas pressure, fuel kernel swelling, and thermal creep. In general the tangential stresses in the coatings during full reactor operation are tensile, with ZrC showing the lowest values among TiC, ZrC, and SiC (TiN and ZrN were excluded from the comprehensive calculations due to a lack of available materials data). The work has highlighted the fact that thermal creep plays a critical role in the development of the stress state of the coatings by relaxing many of the stresses at high temperatures. To perform ion irradiations of sample materials, an irradiation beamline and high-temperature sample irradiation stage was constructed at the University of Wisconsin’s 1.7MV Tandem Accelerator Facility. This facility is now capable of irradiating of materials to high dose while controlling sample temperature up to 800ºC.

Paul A. Demkowicz; Karen Wright; Jian Gan; David Petti; Todd Allen; Jake Blanchard

2006-09-01T23:59:59.000Z

210

The cycling of carbon into and out of dust  

E-Print Network (OSTI)

Observational evidence seems to indicate that the depletion of interstellar carbon into dust shows rather wide variations and that carbon undergoes rather rapid recycling in the interstellar medium (ISM). Small hydrocarbon grains are processed in photo-dissociation regions by UV photons, by ion and electron collisions in interstellar shock waves and by cosmic rays. A significant fraction of hydrocarbon dust must therefore be re-formed by accretion in the dense, molecular ISM. A new dust model (Jones et al., Astron. Astrophys., 2013, 558, A62) shows that variations in the dust observables in the diffuse interstellar medium (nH = 1000 cm^3), can be explained by systematic and environmentally-driven changes in the small hydrocarbon grain population. Here we explore the consequences of gas-phase carbon accretion onto the surfaces of grains in the transition regions between the diffuse ISM and molecular clouds (e.g., Jones, Astron. Astrophys., 2013, 555, A39). We find that significant carbonaceous dust re-processi...

Jones, Anthony P; Koehler, Melanie; Fanciullo, Lapo; Bocchio, Marco; Micelotta, Elisabetta; Verstraete, Laurent; Guillet, Vincent

2014-01-01T23:59:59.000Z

211

Rapid?sampling system for dusts and gases  

Science Journals Connector (OSTI)

The Bureau of Mines has developed a system for the rapid grab sampling of heterogeneous mixtures of gases and dusts during the preignition and postignition stages of dust explosions. The combustion chamber in which the explosion occurs is first fitted with a hypodermic sampling needle with its inlet end at the desired sampling point within the chamber and its sharp injecting end protruding outside of the chamber. Rapid sampling (approximately 25 to 50 ms) is achieved with a double?acting air?pressure?actuated cylinder. The forward stroke of the cylinder thrusts the rubber septum seal of an evacuated glass sampling tube onto the protruding needle which punctures the septum filling the tube with gas and dust from the combustion chamber. The return stroke of the cylinder reseals the sampling tube by returning the mechanism to its original position. The initial time of sampling and the duration of sampling are independently variable and controlled by a microprocessor. Results obtained with a trimodal distribution of coal dust show no significant size discrimination at least up to 70 ?m. Data obtained from laboratory?scale coal dust explosion tests are also presented. Such data provide valuable insights into the basic phenomena involved in explosions.

R. S. Conti; M. Hertzberg; F. T. Duda; K. L. Cashdollar

1983-01-01T23:59:59.000Z

212

Carbon formation and metal dusting in advanced coal gasification processes  

SciTech Connect

The product gases generated by coal gasification systems contain high concentrations of CO and, characteristically, have relatively high carbon activities. Accordingly, carbon deposition and metal dusting can potentially degrade the operation of such gasifier systems. Therefore, the product gas compositions of eight representative gasifier systems were examined with respect to the carbon activity of the gases at temperatures ranging from 480 to 1,090 C. Phase stability calculations indicated that Fe{sub 3}C is stable only under very limited thermodynamic conditions and with certain kinetic assumptions and that FeO and Fe{sub 0.877}S tend to form instead of the carbide. As formation of Fe{sub 3}C is a necessary step in the metal dusting of steels, there are numerous gasifier environments where this type of carbon-related degradation will not occur, particularly under conditions associated with higher oxygen and sulfur activities. These calculations also indicated that the removal of H{sub 2}S by a hot-gas cleanup system may have less effect on the formation of Fe{sub 3}C in air-blown gasifier environments, where the iron oxide phase can exist and is unaffected by the removal of sulfur, than in oxygen-blown systems, where iron sulfide provides the only potential barrier to Fe{sub 3}C formation. Use of carbon- and/or low-alloy steels dictates that the process gas composition be such that Fe{sub 3}C cannot form if the potential for metal dusting is to be eliminated. Alternatively, process modifications could include the reintroduction of hydrogen sulfide, cooling the gas to perhaps as low as 400 C and/or steam injection. If higher-alloy steels are used, a hydrogen sulfide-free gas may be processed without concern about carbon deposition and metal dusting.

DeVan, J.H.; Tortorelli, P.F.; Judkins, R.R.; Wright, I.G.

1997-02-01T23:59:59.000Z

213

The Millennium Gas project aims to undertake smoothed-particle hydrodynamic resimulations of the Millennium Simulation, providing many hundred massive galaxy clusters for comparison with X-ray surveys (170 clusters with kTsl > 3 keV). This paper looks at  

E-Print Network (OSTI)

. Abstract The Millennium Gas project aims to undertake smoothed-particle hydrodynamic-ray surveys (170 clusters with kTsl > 3 keV). This paper looks at the hot gas and stellar fractions-core systems but are successful in matching the hot gas profiles of non-cool-core clusters. Although

Thomas, Peter

214

Equilibrium and thermodynamics of dye removal from aqueous solution by adsorption using rubber wood saw dust  

Science Journals Connector (OSTI)

Batch equilibrium experiments were carried out for the sorption of Bismarck brown onto rubber wood saw dust particles. The operating variables studied were the initial dye concentration, particle diameter and solution temperature. A linearised Langmuir isotherm was found to well represent the equilibrium uptake for the range of operating conditions studied. The monolayer sorption capacity of rubber wood saw dust for the sorption of Bismarck brown was estimated to be 35 mg g?1. The sorption capacity was found to increase with decreasing particle size. The negative value of ?G and ?H suggests the spontaneity and exothermic nature of the process.

K. Vasanth Kumar; K. Porkodi

2009-01-01T23:59:59.000Z

215

Raman spectroscopy of carbon dust samples from NSTX Y. Raitses a,*, C.H. Skinner a  

E-Print Network (OSTI)

.S. Duffy b a Princeton Plasma Physics Laboratory, Princeton, NJ 08543, USA b Department of Geosciences, Princeton University, NJ 08544, USA Received 13 November 2007; accepted 17 January 2008 Abstract The Raman spectrum of dust particles exposed to the NSTX plasma is different from the spectrum of unexposed particles

Duffy, Thomas S.

216

Moon Dust and Coal Ash  

Science Journals Connector (OSTI)

... struck by the similarity between the preliminary descriptions of moon dust and that of the ash residue collected from pulverized ... residue collected from pulverized coal-fired boilers (that is, pulverized fuel ...

A. B. HART; E. RAASK

1969-08-16T23:59:59.000Z

217

PROPERTIES OF NEWLY FORMED DUST GRAINS IN THE LUMINOUS TYPE IIn SUPERNOVA 2010jl  

SciTech Connect

Supernovae (SNe) have been proposed to be the main production sites of dust grains in the universe. However, our knowledge of their importance to dust production is limited by observationally poor constraints on the nature and amount of dust particles produced by individual SNe. In this paper, we present a spectrum covering optical through near-Infrared (NIR) light of the luminous Type IIn supernova 2010jl around one and a half years after the explosion. This unique data set reveals multiple signatures of newly formed dust particles. The NIR portion of the spectrum provides a rare example where thermal emission from newly formed hot dust grains is clearly detected. We determine the main population of the dust species to be carbon grains at a temperature of ?1350-1450 K at this epoch. The mass of the dust grains is derived to be ?(7.5-8.5) × 10{sup –4} M{sub ?}. Hydrogen emission lines show wavelength-dependent absorption, which provides a good estimate of the typical size of the newly formed dust grains (?< 0.1 ?m, and most likely ?< 0.01 ?m). We believe the dust grains were formed in a dense cooling shell as a result of a strong SN-circumstellar media (CSM) interaction. The dust grains occupy ?10% of the emitting volume, suggesting an inhomogeneous, clumpy structure. The average CSM density must be ?> 3 × 10{sup 7} cm{sup –3}, corresponding to a mass loss rate of ?> 0.02 M{sub ?} yr{sup –1} (for a mass loss wind velocity of ?100 km s{sup –1}). This strongly supports a scenario in which SN 2010jl and probably other luminous SNe IIn are powered by strong interactions within very dense CSM, perhaps created by Luminous-Blue-Variable-like eruptions within the last century before the explosion.

Maeda, K.; Nozawa, T.; Folatelli, G.; Moriya, T. J.; Nomoto, K.; Bersten, M.; Quimby, R. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Sahu, D. K.; Anupama, G. C. [Indian Institute of Astrophysics, Koramangala, Bangalore 560 034 (India); Minowa, Y.; Pyo, T.-S. [Subaru Telescope, National Astronomical Observatory of Japan, 650 North A'ohoku Place, Hilo, HI 96720 (United States); Motohara, K.; Kitagawa, Y. [Institute of Astronomy, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Ueno, I.; Kawabata, K. S.; Yamanaka, M. [Hiroshima Astrophysical Science Center, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Kozasa, T. [Department of Cosmosciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810 (Japan); Iye, M., E-mail: keiichi.maeda@ipmu.jp [National Astronomical Observatory, Mitaka, Tokyo (Japan)

2013-10-10T23:59:59.000Z

218

Vacuum friction in rotating particles  

E-Print Network (OSTI)

We study the frictional torque acting on particles rotating in empty space. At zero temperature, vacuum friction transforms mechanical energy into light emission and produces particle heating. However, particle cooling relative to the environment occurs at finite temperatures and low rotation velocities. Radiation emission is boosted and its spectrum significantly departed from a hot-body emission profile as the velocity increases. Stopping times ranging from hours to billions of years are predicted for materials, particle sizes, and temperatures accessible to experiment. Implications for the behavior of cosmic dust are discussed.

A. Manjavacas; F. J. García de Abajo

2010-09-21T23:59:59.000Z

219

Mineral Dust Entrainment and Deposition (DEAD) model: Description and 1990s dust climatology  

E-Print Network (OSTI)

DUST MODEL AND 1990S CLIMATOLOGY Table 5. Trace MetalDUST MODEL AND 1990S CLIMATOLOGY Figure 7. Predicted andDUST MODEL AND 1990S CLIMATOLOGY Mahowald, N. , K. Kohfeld,

Zender, Charles S; Bian, H.; Newman, D.

2003-01-01T23:59:59.000Z

220

DUST-DRIVEN WIND FROM DISK GALAXIES  

SciTech Connect

We study gaseous outflows from disk galaxies driven by radiation pressure on dust grains. We include the effect of bulge and dark matter halo and show that the existence of such an outflow implies a maximum value of disk mass-to-light ratio. We show that the terminal wind speed is proportional to the disk rotation speed in the limit of a cold gaseous outflow, and that in general there is a contribution from the gas sound speed. Using the mean opacity of dust grains and the evolution of the luminosity of a simple stellar population, we then show that the ratio of the wind terminal speed (v{sub {infinity}}) to the galaxy rotation speed (v{sub c}) ranges between 2 and 3 for a period of {approx}10 Myr after a burst of star formation, after which it rapidly decays. This result is independent of any free parameter and depends only on the luminosity of the stellar population and the relation between disk and dark matter halo parameters. We briefly discuss the possible implications of our results.

Sharma, Mahavir; Nath, Biman B. [Raman Research Institute, Sadashiva Nagar, Bangalore 560080 (India); Shchekinov, Yuri, E-mail: mahavir@rri.res.in, E-mail: biman@rri.res.in, E-mail: yus@sfedu.ru [Department of Physics, Southern Federal University, Rostov on Don 344090 (Russian Federation)

2011-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Chemically Consistent Evolutionary Models with Dust  

E-Print Network (OSTI)

As a tool to interpret nearby and high redshift galaxy data from optical to K-band we present our chemically consistent spectrophotometric evolutionary synthesis models. These models take into account the increasing initial metallicity of successive stellar generations using recently published metallicity dependent stellar evolutionary tracks, stellar yields and model atmosphere spectra. The influence of the metallicity is analysed. Dust absorption is included on the basis of gas content and abundance as it varies with time and galaxy type. We compare our models with IUE template spectra and are able to predict UV fluxes for different spectral types. Combined with a cosmological model we obtain evolutionary and k-corrections for various galaxy types and show the differences to models using only solar metallicity input physics as a function of redshift, wavelength band and galaxy type.

C. S. Möller; U. Fritze-v. Alvensleben; K. J. Fricke; D. Calzetti

1999-06-21T23:59:59.000Z

222

Improved high efficiency third stage separator cyclones for separation of fines from fluid catalytic cracking flue gas  

SciTech Connect

Stairmand type small diameter (0.254 m) multicyclones were cold flow tested for fluid catalytic cracking third stage separator application. The gas discharge from the cyclone dust outlet into the common collection hopper was found to far exceed the hopper bleed rate (underflow). The excess gas reentrained dust from the hopper back into cyclones, which lowered collection efficiencies. Vortex {open_quotes}stabilization{close_quotes} using apex cones was unsuccessful whereas a Mobil proprietary cyclone modification was successful in minimizing excess gas discharge and dust reentrainment at the cyclone-hopper boundary. In tests at 700 {degrees}C, the modified cyclones captured all particles above 4 {mu}m. Mobil-Kellogg incorporated the modified cyclones in a new third stage separator design which is targeted for achieving lowest opacity and <50 mg/Nm{sup 3} emissions at the stack. The first such unit will be commercialized in Mobil`s newest catalytic cracker (M.W. Kellogg design) under construction in Altona, Australia in late 1996. 5 refs., 4 figs., 2 tabs.

Chitnis, G.K.; Schatz, K.W. [Mobil Technology Co., Paulsboro, NJ (United States); Bussey, B.K. [M.W. Kellogg Co., Houston, TX (United States)

1996-12-31T23:59:59.000Z

223

Destruction of Interstellar Dust in Evolving Supernova Remnant Shock Waves  

E-Print Network (OSTI)

Supernova generated shock waves are responsible for most of the destruction of dust grains in the interstellar medium (ISM). Calculations of the dust destruction timescale have so far been carried out using plane parallel steady shocks, however that approximation breaks down when the destruction timescale becomes longer than that for the evolution of the supernova remnant (SNR) shock. In this paper we present new calculations of grain destruction in evolving, radiative SNRs. To facilitate comparison with the previous study by Jones et al. (1996), we adopt the same dust properties as in that paper. We find that the efficiencies of grain destruction are most divergent from those for a steady shock when the thermal history of a shocked gas parcel in the SNR differs significantly from that behind a steady shock. This occurs in shocks with velocities >~ 200 km/s for which the remnant is just beginning to go radiative. Assuming SNRs evolve in a warm phase dominated ISM, we find dust destruction timescales are incre...

Slavin, Jonathan D; Jones, Anthony P

2015-01-01T23:59:59.000Z

224

Coal cutting research slashes dust  

SciTech Connect

US Bureau of Mines' research projects aimed at the reduction of coal dust during coal cutting operations are described. These include an investigation of the effects of conical bit wear on respirable dust generation, energy and cutting forces; the determination of the best conical bit mount condition to increase life by enhancing bit rotation; a comparison between chisel- and conical-type cutters. In order to establish a suitable homogeneous reference material for cutting experiments, a synthetic coal with a plaster base is being developed.

Roepke, W.W.

1983-10-01T23:59:59.000Z

225

Anisotropic collective flow of a Lorentz gas  

E-Print Network (OSTI)

Analytical results for the anisotropic collective flow of a Lorentz gas of massless particles scattering on fixed centres are presented.

Nicolas Borghini; Clement Gombeaud

2011-06-30T23:59:59.000Z

226

Using Reconstructed Dust Climatology to Study the Impacts of Martian Dust Storms on Dynamics  

E-Print Network (OSTI)

Using Reconstructed Dust Climatology to Study the Impacts of Martian Dust Storms on Dynamics L@atm.ox.ac.uk) Abstract We have reconstructed the climatology of the dust on Mars using available retrievals and estimates) a reconstruction of the dust optical depth climatology based on weighted gridding for Martian years 24

Cambridge, University of

227

EFFECT OF COAL DUST ONEFFECT OF COAL DUST ON RAILROAD BALLAST STRENGTHRAILROAD BALLAST STRENGTH  

E-Print Network (OSTI)

1 EFFECT OF COAL DUST ONEFFECT OF COAL DUST ON RAILROAD BALLAST STRENGTHRAILROAD BALLAST STRENGTH for Laboratory StudyFouling Mechanism / Need for Laboratory Study Mechanical Properties of Coal DustMechanical Properties of Coal Dust Grain Size AnalysisGrain Size Analysis AtterbergAtterberg LimitsLimits Specific

Barkan, Christopher P.L.

228

Adding coal dust to coal batch  

SciTech Connect

The granulometric composition of coke dust from the dry-slaking machine is determined. The influence of additions of 3-7% coke dust on the quality of industrial coking batch and the coke obtained by box coking is estimated. Adding 1% coke dust to coking batch does not markedly change the coke quality. Industrial equipment for the supply of dry-slaking dust to the batch is described.

V.S. Shved; A.V.Berezin [OAO Koks, Kemerovo (Russian Federation)

2009-05-15T23:59:59.000Z

229

Chirality in interstellar dust and in comets: Life from dead stars  

Science Journals Connector (OSTI)

Interstellar dust grains have mantles of prebiotic organic molecules. A large fraction of the clouds of interstellar dust grains pass close enough to neutron stars for the circularly polarized ultraviolet radiation to produce a 10% or higher enantiomeric excess in the organic grain mantles. The time between such close passages is about ten times larger than the average lifetime of the molecular clouds so that the most prestellar and protostellar clouds contain predominantly left or right handed prebiotic molecules. Comets as agglomerated interstellar dust preserve the initial enantiomeric excess. Even if only 0.1% of the comet material survives as small comet dust particles which preserve their prebiotic molecules there could be ?10251 chances for life to originate from one of these if it lands in water.

J. Mayo Greenberg

1996-01-01T23:59:59.000Z

230

Gas hydrate formation in fine sand  

Science Journals Connector (OSTI)

Gas hydrate formation from two types of dissolved gas (methane and mixed gas) was studied under varying thermodynamic conditions in ... Sea. The testing media consisted of silica sand particles with diameters of ...

XiaoYa Zang; DeQing Liang; NengYou Wu

2013-04-01T23:59:59.000Z

231

Gas Filled Detectors counting & tracking of  

E-Print Network (OSTI)

Gas Filled Detectors counting & tracking of particles energy loss generation of electron-ion+ pairs #12;Gas Filled Detectors Primary and Total Ionization fast charged particles ionize the atoms of a gas fraction of resulting primary electrons have enough kinetic energy to ionize other atoms #12;Gas Filled

Peletier, Reynier

232

Dust transport: Wind blown and mechanical resuspension, July 1983 to December 1984  

SciTech Connect

This study defines the processes that resuspend plutonium (Pu) particles from Pu-contaminated soil at Rocky Flats. Such knowledge can predict the transport of Pu particles from the site and the population dose. A vertical dust flux tower profiled the plume of Pu particles from the site. The data show a 70% reduction between 1 and 10 m in the concentration of coarse and inhalable Pu particles. The respirable particle concentration remained steady at both heights, slightly above background levels. High winds visually resuspend large amounts of dust for short periods, but we suspected that present sampling devices do not function properly above 50 km/h. During a windstorm reaching 80 km/h, the size-selective sampler used seriously underestimated the dust(Pu) concentration. Wind tunnel studies measured resuspension versus wind speed from our prairie grass covered, arid soil. We failed to find a good correlation between resuspension and wind speed. This led to a search for alternative mechanisms of resuspension besides wind erosion. Resuspension of dust(Pu) from grass proved to be important, as well as resuspension from rain splash.

Langer, G.

1986-09-20T23:59:59.000Z

233

A novel aspect of dust in plasma  

SciTech Connect

Nonlinear screening of the dust grains immersed in a homogenous fully ionized electron-ion plasma is investigated. Assuming conservation of entropy, an important relation is obtained between the maximum potential (and therefore the charge) of the dust grain and the temperature of the electrons. The Thomas-Fermi equation is derived for the potential of a dust grain in a nondegenerate plasma suggesting the existence of dust atom with a well defined atomic radius. Furthermore, based on the Born-Oppenheimer approximation, the notion of a dust-grain molecule is introduced in which the protons act like a kind of 'glue' which binds two negatively charged dust grains together, and the motion of the grains have little influence on that binding force. Finally, considering the weak interaction between the proton clouds of two dust grains, an expression of exchange energy is obtained.

Tsintsadze, N.L.; Murtaza, G.; Ehsan, Z. [Department of Plasma Physics, Tbilisi State University (Georgia); National Centre for Mathematics and Salam Chair in Physics, G.C. University Lahore, 54000 (Pakistan); National Centre for Mathematics and Salam Chair in Physics, G.C. University Lahore, 54000 (Pakistan)

2006-02-15T23:59:59.000Z

234

ASYMMETRIES AND OUTFLOWS IN THE CIRCUMSTELLAR DUST OF MIRA A A. A. Chandler, K. Tatebe, E. H. Wishnow, D. D. S. Hale, and C. H. Townes  

E-Print Network (OSTI)

. Wishnow, D. D. S. Hale, and C. H. Townes Space Sciences Laboratory and Department of Physics, University shells as they tran- sition to the proto­planetary nebula stage. The gas and dust they emit, an estimated

California at Berkeley, University of

235

Coal cutting research slashes dust  

SciTech Connect

The Coal-Cutting Technology Group at the Bureau of Mine's Twin Cities Research Center is investigating ways to reduce primary dust generated by coal cutting. The progression of research within the program is from fundamental laboratory research, to fundamental field research, to field concept verification. Then the Bureau recommends warranted changes and/or prototype development to industry. Currently the Cutting Technology Group has several projects in each phase of research. The Bureau's current fundamental studies of bit characteristics are directed to determining the effects of conical bit wear on primary respirable dust generation, energy, and cutting forces; establishing best conical bit mount condition to increase life by enhancing bit rotation; and comparing chisel-type cutters to conical-type cutters. Additionally, to establish a suitable homogeneous reference material for cutting experiments, a synthetic coal with a plaster base is being developed.

Roepke, W.W.

1983-10-01T23:59:59.000Z

236

Coal cutting research slashes dust  

SciTech Connect

The Coal-Cutting Technology Group at the Bureau of Mines Twin Cities (MN) Research Center is investigating ways to reduce primary dust generated by coal cutting. The progression of research within the program is from fundamental laboratory research, to fundamental field research, to field concept verification. Then the Bureau recommends warranted changes and/or prototype development to industry. Currently the group has several projects in each phase of research. The Bureau's current fundamental studies of bit characteristics are directed toward determining the effects of conical bit wear on primary respirable dust generation, energy, and cutting forces; establishing best conical bit mount condition to increase life by enhancing bit rotation; and comparing chisel-type cutters to conical-type cutters. Additionally, to establish a suitable homogeneous reference material for cutting experiments, a synthetic coal with a plaster base is being developed.

Roepke, W.W.

1983-10-01T23:59:59.000Z

237

Collisionless damping of nonlinear dust ion acoustic wave due to dust charge fluctuation  

Science Journals Connector (OSTI)

A dissipation mechanism for the damping of the nonlinear dust ion acoustic wave in a collisionless dusty plasma consisting of nonthermal electrons, ions, and variable charge dust grains has been investigated. It is shown that the collisionless damping due to dust charge fluctuation causes the nonlinear dust ion acoustic wave propagation to be described by the damped Korteweg-de Vries equation. Due to the presence of nonthermal electrons, the dust ion acoustic wave admits both positive and negative potential and it suffers less damping than the dust acoustic wave, which admits only negative potential.

Samiran Ghosh; Tushar K. Chaudhuri; Susmita Sarkar; Manoranjan Khan; M. R. Gupta

2002-03-21T23:59:59.000Z

238

Polyfluoroalkyl chemicals in house dust  

SciTech Connect

We developed a high throughput analytical method using on-line solid phase extraction coupled with isotope dilution high-performance liquid chromatography-tandem mass spectrometry (on-line SPE-HPLC-MS/MS) to simultaneously determine the concentrations of 17 polyfluoroalkyl chemicals (PFCs) in house dust. The sample preparation includes dispersion of the dust samples in 0.1 M formic acid:MeOH (1:1), followed by agitation and filtration, addition of the isotope-labeled internal standard solution to the filtrate, and analysis by on-line SPE-HPLC-MS/MS. The limits of quantitation were <4.0 ng/g. The method accuracies ranged between 73.2% and 100.2% for the different analytes at two spike levels. We confirmed the validity of the method by analyzing 39 household dust samples collected in 2004. Of the 17 PFCs measured, 6 of them-perfluorobutane sulfonate (PFBuS), N-ethyl-perfluorooctane sulfonamide, 2-(N-ethyl-perfluorooctane sulfonamido) acetic acid (Et-PFOSA-AcOH), 2-(N-methyl-perfluorooctane sulfonamido) ethanol (Me-PFOSA-EtOH), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS)-had detection frequencies >70%. We detected PFOS, PFBuS, and PFHxS at the highest median concentration, followed by Et-PFOSA-AcOH and Me-PFOSA-EtOH.

Kato, Kayoko [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy., Mailstop F53, Atlanta, GA 30341 (United States)] [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy., Mailstop F53, Atlanta, GA 30341 (United States); Calafat, Antonia M., E-mail: acalafat@cdc.gov [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy., Mailstop F53, Atlanta, GA 30341 (United States); Needham, Larry L. [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy., Mailstop F53, Atlanta, GA 30341 (United States)] [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy., Mailstop F53, Atlanta, GA 30341 (United States)

2009-07-15T23:59:59.000Z

239

Atmospheric Movement of Microorganisms in Clouds of Desert Dust and Implications for Human Health  

Science Journals Connector (OSTI)

...general, high-energy wind conditions in...western deserts of Egypt, 44 genera and 102...loss of recovery efficiency due to microorganisms...air-dust particles from Egypt. Mycopathologia...western desert of Egypt. Afr. J. Sci...S. Department of Energy, DOE/NV/10845-60...

Dale W. Griffin

2007-07-01T23:59:59.000Z

240

A new model of composite interstellar dust grains  

E-Print Network (OSTI)

The approach to model composite interstellar dust grains, using the exact solution to the light scattering problem for multi-layered spheres as suggested by Voshchinnikov & Mathis (1999), is further developed. Heterogeneous scatteres are represented by particles with very large number of shells, each including a homogeneous layer per material considered (amorphous carbon, astronomical silicate and vacuum). The applicability of the effective medium theory (EMT) mostly utilized earlier to approximate inhomogeneous interstellar grains is examined on the basis of the new model. It is shown that the EMT rules generally have an accuracy of several percent in the whole range of particle sizes provided the porosity does not exceed about 50%. For larger porosity, the EMT rules give wrong results. Using the model, we reanalyze various basic features of cosmic dust -- interstellar extinction, scattered radiation, infrared radiation, radiation pressure, etc. As an example of the potential of the model, it is applied to reproduce the extinction curves in the directions to $\\zeta$ Oph and $\\sigma$ Sco using subsolar cosmic abundances. We also conclude that metallic iron even in negligible amount ($\\la 1$ % by the volume fraction) is unlikely to form a layer on or inside a grain because of peculiar absorption of radiation by such particles.

N. V. Voshchinnikov; V. B. Il'in; Th. Henning; D. N. Dubkova

2003-03-07T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

NNWSI PROJECT ELEMENT WBS-1.2.6.9.4.6.1.B INTERIM REPORT ON DUST CONTROL PROPOSALS  

SciTech Connect

This report presents interim findings of studies conducted to evaluate dust control equipment during prototype drilling. Based on available data on silica content, type, particle size, and on proposed dry drilling operations, it is estimated that allowable exposures to free silica will range from 0.07 to 1.5 mg/cu meter. They have concluded that airborne concentrations of dust may approach or exceed these values during normal operations, based on studies conducted as part of this task.

D.J. Burton

2005-09-06T23:59:59.000Z

242

Dust extinction and absorption: the challenge of porous grains  

E-Print Network (OSTI)

In many models of dusty objects in space the grains are assumed to be composite or fluffy. However, the computation of the optical properties of such particles is still a very difficult problem. We analyze how the increase of grain porosity influences basic features of cosmic dust -- interstellar extinction, dust temperature, infrared bands and millimeter opacity. Porous grains can reproduce the flat extinction across the $3 - 8 \\mkm$ wavelength range measured for several lines of sight by {\\it ISO} and {\\it Spitzer}. Porous grains are generally cooler than compact grains. At the same time, the temperature of very porous grains becomes slightly larger in the case of the EMT-Mie calculations in comparison with the results found from the layered-sphere model. The layered-sphere model predicts a broadening of infrared bands and a shift of the peak position to larger wavelengths as porosity grows. In the case of the EMT-Mie model variations of the feature profile are less significant. It is also shown that the millimeter mass absorption coefficients grow as porosity increases with a faster growth occurring for particles with Rayleigh/non-Rayleigh inclusions. As a result, for very porous particles the coefficients given by two models can differ by a factor of about 3. It is found that an increase of porosity leads to an increase of extinction cross sections at some wavelengths and a decrease at others depending on the grain model. However, this behaviour is sufficient to reproduce the extinction curve in the direction of the star $\\sigma$ Sco using current solar abundances. In the case of the star $\\zeta$ Oph our model requires larger amounts of carbon and iron in the dust-phase than is available.

N. V. Voshchinnikov; V. B. Il'in; Th. Henning; D. N. Dubkova

2005-09-11T23:59:59.000Z

243

Sterrewacht Gas evolution in protoplanetary disks  

E-Print Network (OSTI)

Sterrewacht Leiden Gas evolution in protoplanetary disks W.F. Thi , E.F. van Dishoeck , G are surrounded by 10 ­10 M of gas+dust in disks with sizes of 100­400 AU. This material may form extrasolar planets. 3 Disks have also been imaged around Vega-like stars, but are thought to be gas­poor with "!#$ M

Zadelhoff, Gerd-Jan van

244

Laboratory investigation of the dust explosibility characteristics of three Nova Scotia coals  

Science Journals Connector (OSTI)

The explosion characteristics of coal dust/air and methane/coal dust/air mixtures have been determined experimentally. All tests were conducted at initial pressures of nominally 1.0 bar in a 26 / spherical explosion bomb. Run-of-mine coal from the Prince, Lingan and Phalen seams of the Cape Breton Development Corporation was used. Two size fractions of each coal were tested at dust concentrations ranging from the lean flammability limit to 1.0 kg m?3. The explosion parameters measured for each test were the maximum explosion pressure, Pmax, and the maximum rate of pressure rise, (dP/dt)max. Methane addition to the coal dust/air mixtures was found to increase both Pmax and (dP/dt)max, the effect being most significant at low dust concentrations. A reduction in mass mean diameter of the coal or an increase in the parent coal volatile content was found to have a similar effect on Pmax and (dP/dt)max. These observations are consistent with a description of coal dust flame propagation by gas-phase combustion of devolatilization products.

Paul R. Amyotte; Kenneth J. Mintz; Michael J. Pegg; Yu-Hong Sun; Kenneth I. Wilkie

1991-01-01T23:59:59.000Z

245

Optical Properties of Saharan Dust and Asian Dust: Application to Radiative Transfer Simulations  

E-Print Network (OSTI)

Because the bulk optical properties of dust are largely dependent on their chemical composition, published reports from numerous dust field studies enabled us to compile observation data sets to derive the effective complex refractive indices...

Fang, Guangyang

2012-07-16T23:59:59.000Z

246

The effect of a dust size distribution on electrostatic sheaths in unmagnetized dusty plasmas  

SciTech Connect

In this work, the structure of plasma sheaths in presence of dust particles with different sizes is investigated numerically in a multifluid framework, where the dust size distribution is modeled by Gauss' law. For this, we have established a 1D, stationary, unmagnetized, and weakly collisional electronegative dusty plasma sheath model. The electrons and negative ions are considered in a local thermodynamic equilibrium, therefore, described by a Boltzmann distribution. On the other hand, positive ions and dust grains are described by fluid equations. The charging process is described by the orbit motion limited model. It is shown that taking into account dust grains with different sizes reduces considerably the sheath thickness. The behavior of dust surface potential is not affected, but the dust charge number is reduced, as well as the electrostatic force. It results in a decrease of layered structure. The presence of negative ions makes the structure of the electrostatic potential more oscillatory. The other physical parameters are also analyzed and discussed.

Benlemdjaldi, D. [Quantum Electronics Laboratory, Faculty of Physics, U.S.T.H.B. BP 32 El-Alia Bab-Ezzouar, Algiers 16111 (Algeria); Departement de Physique, Ecole Normale Superieure BP 92 Vieux-Kouba, Algiers 16050 (Algeria); Tahraoui, A. [Quantum Electronics Laboratory, Faculty of Physics, U.S.T.H.B. BP 32 El-Alia Bab-Ezzouar, Algiers 16111 (Algeria); Hugon, R.; Bougdira, J. [Institut Jean Lamour, Departement CP2S UMR 7198 CNRS, Universite de Lorraine, BP 70239, 54506 Vandoeuvre-les-Nancy cedex (France)

2013-04-15T23:59:59.000Z

247

The effects of the Tidal Force on Shear Instabilities in the Dust Layer of the Solar Nebula  

E-Print Network (OSTI)

The linear analysis of the instability due to vertical shear in the dust layer of the solar nebula is performed. The following assumptions are adopted throughout this paper: (1) The self-gravity of the dust layer is neglected. (2) One fluid model is adopted, where the dust aggregates have the same velocity with the gas due to strong coupling by the drag force. (3) The gas is incompressible. The calculations with both the Coriolis and the tidal forces show that the tidal force has a stabilizing effect. The tidal force causes the radial shear in the disk. This radial shear changes the wave number of the mode which is at first unstable, and the mode is eventually stabilized. Thus the behavior of the mode is divided into two stages: (1) the first growth of the unstable mode which is similar to the results without the tidal force, and (2) the subsequent stabilization due to an increase of the wave number by the radial shear. If the midplane dust/gas density ratio is smaller than 2, the stabilization occurs before the unstable mode grows largely. On the other hand, the mode grows faster by one hundred orders of magnitude, if this ratio is larger than 20. Because the critical density of the gravitational instability is a few hundreds times as large as the gas density, the hydrodynamic instability investigated in this paper grows largely before the onset of the gravitational instability. It is expected that the hydrodynamic instability develops turbulence in the dust layer and the dust aggregates are stirred up to prevent from settling further. The formation of planetesimals through the gravitational instabilities is difficult to occur as long as the dust/gas surface density ratio is equal to that for the solar abundance.

Naoki Ishitsu; Minoru Sekiya

2003-05-30T23:59:59.000Z

248

Characteristics of airborne coal mine dust and its implication to coal workers' pneumoconiosis  

SciTech Connect

Size selective airborne dust samples were collected using 4-stage cassette impactors at nine different locations in continuous mining sections in each of five coal seams located in the Appalachian bituminous coal field. These coal seams were the Upper Freeport, Pittsburgh, Kittanning, Coalburg, and Pocahontas. Mineralogical analyses were performed by an x-ray powder diffraction photographic technique. The distributions of total and respirable dust concentrations were fit best by a log-normal distribution. The effects of the coal seam and the sampling location on dust levels were significant. The results of the particle size distribution analyses suggest that coal mine dust has a multi-modal distribution. The effects of the coal seam and the sampling locations were significant. The distributions obtained were often affected by such mine-related variables as ventilation rate, relative humidity, and the section dimensions. Nine minerals commonly found in the coal mine dust samples collected from the coal seams studied were illite, calcite, kaolinite, quartz, dolomite, siderite, gypsum, anhydrite, and pyrite in descending order of magnitude. Relative abundance of all mineral species except siderite and gypsum was coal seam specific and suggests that existence of coal seam variability of mineral content. Although mineral content was affected by sampling locations and the sections within a mine, the magnitude was small when compared with that of cal seams. Mineral content also appears to be affected by particle size, although no particular pattern was observed.

Kim, H.

1989-01-01T23:59:59.000Z

249

Dust negative ion acoustic shock waves considering dust size distribution effect  

SciTech Connect

A multi-ion dusty plasma containing hot isothermal electrons, ions (light positive ions and heavy negative ions), and extremely and negatively charged dust grains is studied in the present paper. The dust negative ion acoustic shock waves have been investigated by employing the reductive perturbation method. How the dust size distribution affects the height and the thickness of the nonlinear shock wave is studied. It is noted that the different dust size distribution has different shock wave form and different moving speed.

Ma Yirong; Wang Canglong; Zhang Jianrong; Sun Jianan; Duan Wenshan [College of Physics and Electronic Engineering and Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou 730070, China and Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Yang Lei [College of Physics and Electronic Engineering and Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou 730070 (China) and Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Department of Physics, Lanzhou University, Lanzhou 730000 (China)

2012-11-15T23:59:59.000Z

250

Brownian Motion of Stars, Dust, and Invisible Matter  

Science Journals Connector (OSTI)

Treating the motion of a dust particle suspended in a liquid as a random walk Einstein in 1905 derived an equation describing the diffusion of the particle’s probability distribution in configuration space. Fokker and Planck extended this work to describe the velocity distribution of the particles. Their equation and its solutions have been applied to many problems in nature starting with the motion of Brownian particles in a liquid. Chandrasekhar derived the Fokker?Planck equation for stars and showed that long?range gravitational encounters provide a drag force dynamical friction which is important in the evolution of star clusters and the formation of galaxies. In certain circumstances Fokker?Planck evolution also describes the evolution of dark (invisible) matter in the universe. In the early universe the thermal decoupling of weakly interacting massive particles from the plasma of relativistic leptons and photons is governed by Fokker?Planck evolution. The resulting dissipation imprints a minimum length scale for cosmic density fluctuations. Still later these density fluctuations produce stochastic gravitational forces on the dark matter as it begins to cluster under gravity. The latter example provides an exact derivation of the Fokker?Planck equation without the usual assumption of Markovian dynamics.

Edmund Bertschinger

2006-01-01T23:59:59.000Z

251

Variability of Natural Dust Erosion from a Coal Pile  

Science Journals Connector (OSTI)

A study of fugitive dust emissions from a pile of crushed coal revealed that, in addition to emitting dust to the atmosphere during periods of pile management (human) activity, dust is also emitted during periods without human activity. This “...

Stephen F. Mueller; Jonathan W. Mallard; Qi Mao; Stephanie L. Shaw

252

Experimental Study of Nonlinear Dust Acoustic Solitary Waves in a Dusty Plasma  

Science Journals Connector (OSTI)

The excitation and propagation of finite-amplitude low-frequency solitary waves are investigated in an argon plasma impregnated with kaolin dust particles. A nonlinear longitudinal dust acoustic solitary wave is excited by pulse modulating the discharge voltage with a negative potential. It is found that the velocity of the solitary wave increases and the width decreases with the increase of the modulating voltage, but the product of the solitary wave amplitude and the square of the width remains nearly constant. The experimental findings are compared with analytic soliton solutions of a model Korteveg–de Vries equation.

P. Bandyopadhyay; G. Prasad; A. Sen; P. K. Kaw

2008-08-08T23:59:59.000Z

253

Features of coal dust dynamics at action of differently oriented forces in granular filtering medium  

E-Print Network (OSTI)

The process of the coal dust particles transportation and structurization in the experimental horizontal model of air filter with the cylindrical coal adsorbent granules as in the iodine air filter at the nuclear power plant is researched. In the investigated case the vector of carrying away force of air flow and the vector of gravitation force are mutually perpendicular, and the scattering of the dust particles on the granules occurs in the normal directions. It is found that the phenomenon of non controlled spontaneous sharp increase of aerodynamic resistance in the iodine air filter under the big integral volumes of filtered air and the big masses of introduced coal dust particles is not observed at the described experimental conditions in distinction from the case of the parallel orientation of this forces as in the vertical iodine air filters at the nuclear power plant. The quantitative measurements of the main parameters of the process of the dust masses transportation and structurization are made on a ...

Neklyudov, I M; Poltinin, P Ya; Ledenyov, O P

2013-01-01T23:59:59.000Z

254

Features of coal dust dynamics at action of differently oriented forces in granular filtering medium  

E-Print Network (OSTI)

The process of the coal dust particles transportation and structurization in the experimental horizontal model of air filter with the cylindrical coal adsorbent granules as in the iodine air filter at the nuclear power plant is researched. In the investigated case the vector of carrying away force of air flow and the vector of gravitation force are mutually perpendicular, and the scattering of the dust particles on the granules occurs in the normal directions. It is found that the phenomenon of non controlled spontaneous sharp increase of aerodynamic resistance in the iodine air filter under the big integral volumes of filtered air and the big masses of introduced coal dust particles is not observed at the described experimental conditions in distinction from the case of the parallel orientation of this forces as in the vertical iodine air filters at the nuclear power plant. The quantitative measurements of the main parameters of the process of the dust masses transportation and structurization are made on a developed experimental model of the iodine air filter with the cylindrical coal adsorbent granules.

I. M. Neklyudov; L. I. Fedorova; P. Ya. Poltinin; O. P. Ledenyov

2013-01-24T23:59:59.000Z

255

Imaging alpha particle detector  

DOE Patents (OSTI)

A method and apparatus for detecting and imaging alpha particles sources is described. A dielectric coated high voltage electrode and a tungsten wire grid constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source to be quantitatively or qualitatively analyzed. A thin polyester film window allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods. A significant increase in sensitivity over other alpha particle detectors is observed, and the device has very low sensitivity to gamma or beta emissions which might otherwise appear as noise on the alpha particle signal.

Anderson, D.F.

1980-10-29T23:59:59.000Z

256

Imaging alpha particle detector  

DOE Patents (OSTI)

A method and apparatus for detecting and imaging alpha particles sources is described. A conducting coated high voltage electrode (1) and a tungsten wire grid (2) constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source (3) to be quantitatively or qualitatively analyzed. A thin polyester film window (4) allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods. A significant increase in sensitivity over other alpha particle detectors is observed, and the device has very low sensitivity to gamma or beta emissions which might otherwise appear as noise on the alpha particle signal.

Anderson, David F. (Los Alamos, NM)

1985-01-01T23:59:59.000Z

257

Methods of forming a fluidized bed of circulating particles  

DOE Patents (OSTI)

There is disclosed an apparatus for forming a fluidized bed of circulating particles. In an embodiment, the apparatus includes a bottom portion having a sidewall, the sidewall defining a curvilinear profile, and the bottom portion configured to contain a bed of particles; and a gas inlet configured to produce a column of gas to carry entrained particles therein. There is disclosed a method of forming a fluidized bed of circulating particles. In an embodiment, the method includes positioning particles within a bottom portion having a sidewall, the sidewall defining a curvilinear profile; producing a column of gas directed upwardly through a gas inlet; carrying entrained particles in the column of gas to produce a fountain of particles over the fluidized bed of circulating particles and subside in the particle bed until being directed inwardly into the column of gas within the curvilinear profile.

Marshall, Douglas W. (Blackfoot, ID)

2011-05-24T23:59:59.000Z

258

Uncertainty in Particle Number Modal Analysis during Transient Operation of Compressed Natural Gas, Diesel, and Trap-Equipped Diesel Transit Buses  

Science Journals Connector (OSTI)

A number of recent studies have examined the mass- and number-weighted particulate emissions from diesel engines and vehicles, chiefly using laboratory tests under steady-state vehicle or engine operation. ... However, there remains little fundamental data on the relationships between vehicle operating mode (cruise, idle, acceleration, decelera tion) and ultrafine particle emissions, both for diesel and especially for diesel alternatives. ... The number of ELPI data points measured for individual test cycles ranged from 120 to 1000, depending on the recorded ELPI time resolution and overall length of the driving cycle (?10?35 min). ...

Britt A. Holmén; Yingge Qu

2004-03-10T23:59:59.000Z

259

Metal Dusting of Heat-Resistant Alloys  

E-Print Network (OSTI)

Metal dusting leads to disintegration of such alloys as iron and nickel-based into a “dust” of particulate metal, metal carbide, carbon, and/or oxide. It occurs in strongly carburising environments at 400-900°C. Literature survey has shown...

Al-Meshari, Abdulaziz I

260

Global dust model intercomparison in AeroCom phase I  

E-Print Network (OSTI)

Miami (19) cap- ture the transatlantic transport of Saharanside the period of maximum transatlantic Saharan dust trans-stations affected by transatlantic dust transport (stations

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Oil shale retorting with steam and produced gas  

SciTech Connect

This patent describes a process for retorting oil shale in a vertical retort. It comprises introducing particles of oil shale into the retort, the particles of oil shale having a minimum size such that the particles are retained on a screen having openings 1/4 inch in size; contacting the particles of oil shale with hot gas to heat the particles of oil shale to a state of pyrolysis, thereby producing retort off-gas; removing the off-gas from the retort; cooling the off-gas; removing oil from the cooled off-gas; separating recycle gas from the off-gas, the recycle gas comprising steam and produced gas, the steam being present in amount, by volume, of at least 50% of the recycle gas so as to increase the yield of sand oil; and heating the recycle gas to form the hot gas.

Merrill, L.S. Jr.; Wheaton, L.D.

1991-08-20T23:59:59.000Z

262

Definition: Liquid natural gas | Open Energy Information  

Open Energy Info (EERE)

Liquid natural gas Liquid natural gas Jump to: navigation, search Dictionary.png Liquid natural gas Natural gas (primarily methane) that has been liquefied by reducing its temperature to -260 degrees Fahrenheit at atmospheric pressure.[1] View on Wikipedia Wikipedia Definition Liquefied natural gas or LNG is natural gas that has been converted to liquid form for ease of storage or transport. Liquefied natural gas takes up about 1/600th the volume of natural gas in the gaseous state. It is odorless, colorless, non-toxic and non-corrosive. Hazards include flammability after vaporization into a gaseous state, freezing and asphyxia. The liquefaction process involves removal of certain components, such as dust, acid gases, helium, water, and heavy hydrocarbons, which could cause difficulty downstream. The natural gas is then condensed into a

263

Dust Emission from the Perseus Molecular Cloud  

E-Print Network (OSTI)

Using far-infrared emission maps taken by IRAS and Spitzer and a near-infrared extinction map derived from 2MASS data, we have made dust temperature and column density maps of the Perseus molecular cloud. We show that the emission from transiently heated very small grains and the big grain dust emissivity vary as a function of extinction and dust temperature, with higher dust emissivities for colder grains. This variable emissivity can not be explained by temperature gradients along the line of sight or by noise in the emission maps, but is consistent with grain growth in the higher density and lower temperature regions. By accounting for the variations in the dust emissivity and VSG emission, we are able to map the temperature and column density of a nearby molecular cloud with better accuracy than has previously been possible.

S. Schnee; J. Li; A. A. Goodman; A. I. Sargent

2008-05-27T23:59:59.000Z

264

Brownian Motion of Stars, Dust, and Invisible Matter  

E-Print Network (OSTI)

Treating the motion of a dust particle suspended in a liquid as a random walk, Einstein in 1905 derived an equation describing the diffusion of the particle's probability distribution in configuration space. Fokker and Planck extended this work to describe the velocity distribution of the particles. Their equation and its solutions have been applied to many problems in nature starting with the motion of Brownian particles in a liquid. Chandrasekhar derived the Fokker-Planck equation for stars and showed that long-range gravitational encounters provide a drag force, dynamical friction, which is important in the evolution of star clusters and the formation of galaxies. In certain circumstances, Fokker-Planck evolution also describes the evolution of dark (invisible) matter in the universe. In the early universe, the thermal decoupling of weakly interacting massive particles from the plasma of relativistic leptons and photons is governed by Fokker-Planck evolution. The resulting dissipation imprints a minimum length scale for cosmic density fluctuations. Still later, these density fluctuations produce stochastic gravitational forces on the dark matter as it begins to cluster under gravity. The latter example provides an exact derivation of the Fokker-Planck equation without the usual assumption of Markovian dynamics.

Edmund Bertschinger

2006-08-28T23:59:59.000Z

265

Dust removal in radio-frequency plasmas by a traveling potential modulation  

SciTech Connect

The dust contamination in plasma deposition processes plays a crucial role in the quality and the yield of the products. To improve the quality and the yield of plasma processing, a favorable way is to remove the dust particles actively from the plasma reactors.Our recent experiments in the striped electrode device show that a traveling plasma modulation allows for a systematic particle removal independent of the reactor size. Besides the rf powered electrode, the striped electrode device includes a segmented electrode that consists of 100 electrically insulated narrow stripes. A traveling potential profile is produced by the modulation of the voltage signals applied on the stripes. The dust particles are trapped in the potential wells and transported with the traveling of the potential profile.The particle-in-cell (PIC) simulation on the potential above the segmented electrode indicates that the traveling potential profile can be realized either by applying low-frequency (0.1-10 Hz) voltage signals with a fixed phase shift between adjacent stripes or high-frequency (10 kHz a circumflex AS 100 MHz) signals with the amplitudes modulated by a low-frequency envelope. The transportation of the dust particles is simulated with a two-dimensional molecular dynamics (MD) code with the potential profile obtained from the PIC simulation. The MD results reproduce the experimental observations successfully.This technology allows for an active removal of the contaminating particles in processing plasmas and it is independent of the reactor size. The removal velocity is controllable by adjusting the parameters for the modulation.

Li Yangfang; Jiang Ke; Thomas, Hubertus M.; Morfill, Gregor E. [Max-Planck-Institute for Extraterrestrial Physics, 85748 Garching (Germany)

2010-06-16T23:59:59.000Z

266

Particle Astrophysics  

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

Particle Astrophysics Particle Astrophysics Understanding discoveries at the Energy, Intensity, and Cosmic Frontiers Get Expertise Rajan Gupta (505) 667-7664 Email Bruce Carlsten...

267

Composition and Reactions of Atmospheric Aerosol Particles  

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

Composition and Reactions of Composition and Reactions of Atmospheric Aerosol Particles Composition and Reactions of Atmospheric Aerosol Particles Print Wednesday, 29 June 2005 00:00 Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based on high-resolution scanning transmission x-ray images obtained at the ALS have revealed chemical reactions on and in atmospheric aerosol particles that caused particle growth while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

268

Composition and Reactions of Atmospheric Aerosol Particles  

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

Composition and Reactions of Atmospheric Aerosol Particles Print Composition and Reactions of Atmospheric Aerosol Particles Print Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based on high-resolution scanning transmission x-ray images obtained at the ALS have revealed chemical reactions on and in atmospheric aerosol particles that caused particle growth while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

269

Composition and Reactions of Atmospheric Aerosol Particles  

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

Composition and Reactions of Atmospheric Aerosol Particles Print Composition and Reactions of Atmospheric Aerosol Particles Print Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based on high-resolution scanning transmission x-ray images obtained at the ALS have revealed chemical reactions on and in atmospheric aerosol particles that caused particle growth while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

270

Neutron Gas  

Science Journals Connector (OSTI)

We assume that the neutron-neutron potential is well-behaved and velocity-dependent. We can then apply perturbation theory to find the energy per particle of a neutron gas, in the range of Fermi wave numbers 0.5particle (within 0.5 Mev); our values tend to run an Mev below values found by Brueckner et al., for the Gammel-Thaler potential. Wider divergences appear at higher densities. Our values, and Brueckner's are higher than those found by Salpeter by a semiempirical approach. A crude estimate of the second-order energy for our potentials indicates that perturbation theory converges rapidly in the density range considered. Our results suggest that at moderately low densities the energy/particle in a many-body system is insensitive to the shape or nonlocal character of the assumed two-body potential.

J. S. Levinger and L. M. Simmons

1961-11-01T23:59:59.000Z

271

CAN DUST EMISSION BE USED TO ESTIMATE THE MASS OF THE INTERSTELLAR MEDIUM IN GALAXIES-A PILOT PROJECT WITH THE HERSCHEL REFERENCE SURVEY  

SciTech Connect

The standard method for estimating the mass of the interstellar medium (ISM) in a galaxy is to use the 21 cm line to trace the atomic gas and the CO 1-0 line to trace the molecular gas. In this paper, we investigate the alternative technique of using the continuum dust emission to estimate the mass of gas in all phases of the ISM. Using Herschel observations of 10 galaxies from the Herschel Reference Survey and the Herschel Virgo Cluster Survey, we show that the emission detected by Herschel is mostly from dust that has a temperature and emissivity index similar to that of dust in the local ISM in our galaxy, with the temperature generally increasing toward the center of each galaxy. We calibrate the dust method using the CO and 21 cm observations to provide an independent estimate of the mass of hydrogen in each galaxy, solving the problem of the uncertain ''X-factor'' for the CO observations by minimizing the dispersion in the ratio of the masses estimated using the two methods. With the calibration for the dust method and the estimate of the X-factor produced in this way, the dispersion in the ratio of the two gas masses is 25%. The calibration we obtain for the dust method is similar to those obtained from Herschel observations of M31 and from Planck observations of the Milky Way. We discuss the practical problems in using this method.

Eales, Stephen; Smith, Matthew W. L.; Auld, Robbie; Davies, Jon; Gear, Walter; Gomez, Haley [School of Physics and Astronomy, Cardiff University, Queens Buildings, The Parade, Cardiff CF24 3AA (United Kingdom); Baes, Maarten; De Looze, Ilse; Gentile, Gianfranco; Fritz, Jacopo [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium); Bendo, George J. [UK ALMA Regional Centre Node, Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Bianchi, Simone [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze (Italy); Boselli, Alessandro; Ciesla, Laure [Laboratoire d'Astrophysique de Marseilles, UMR6110 CNRS, 38 rue F. Joliot-Curie, F-1338 Marseilles (France); Clements, David [Astrophysics Group, Imperial College, Blackett Lab, Prince Consort Road, London SW7 2AZ (United Kingdom); Cooray, Asantha [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Cortese, Luca [European Southern Observatory, Karl-Schwarzschild-Strasse 2 D-85748, Garching bei Munchen (Germany); Galametz, Maud [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Hughes, Tom [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); Madden, Suzanne [Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot, Irfu/Service d'Astrophysique, F-91191 Gif sur Yvette (France); and others

2012-12-20T23:59:59.000Z

272

FRAGMENTATION AND EVOLUTION OF MOLECULAR CLOUDS. II. THE EFFECT OF DUST HEATING  

SciTech Connect

We investigate the effect of heating by luminosity sources in a simulation of clustered star formation. Our heating method involves a simplified continuum radiative transfer method that calculates the dust temperature. The gas temperature is set by the dust temperature. We present the results of four simulations; two simulations assume an isothermal equation of state and the two other simulations include dust heating. We investigate two mass regimes, i.e., 84 M{sub sun} and 671 M{sub sun}, using these two different energetics algorithms. The mass functions for the isothermal simulations and simulations that include dust heating are drastically different. In the isothermal simulation, we do not form any objects with masses above 1 M{sub sun}. However, the simulation with dust heating, while missing some of the low-mass objects, forms high-mass objects ({approx}20 M{sub sun}) which have a distribution similar to the Salpeter initial mass function. The envelope density profiles around the stars formed in our simulation match observed values around isolated, low-mass star-forming cores. We find the accretion rates to be highly variable and, on average, increasing with final stellar mass. By including radiative feedback from stars in a cluster-scale simulation, we have determined that it is a very important effect which drastically affects the mass function and yields important insights into the formation of massive stars.

Urban, Andrea; Evans, Neal J. [Department of Astronomy, University of Texas, Austin, TX 78712 (United States); Martel, Hugo [Departement de Physique, genie physique et optique, Universite Laval, Quebec, QC G1K 7P4 (Canada)

2010-02-20T23:59:59.000Z

273

Charging of Dust Grains in a Plasma  

Science Journals Connector (OSTI)

Charging of micron-sized dust grains in a plasma has been investigated experimentally. Dust grains were dispersed into a fully ionized, steady-state, magnetized plasma column consisting of electrons and K+ ions, both at a temperature of ?0.2 eV. Langmuir probe measurements were used to determine how the negative charge in the plasma is divided between free electrons and dust grains. By varying the ratio d?D between the intergrain spacing and the plasma Debye length, the predicted reduction in the grain charge for the case of "closely packed" grains d?D<1 has been demonstrated experimentally.

A. Barkan; N. D'Angelo; R. L. Merlino

1994-12-05T23:59:59.000Z

274

Mercury sorbent delivery system for flue gas  

DOE Patents (OSTI)

The invention presents a device for the removal of elemental mercury from flue gas streams utilizing a layer of activated carbon particles contained within the filter fabric of a filter bag for use in a flue gas scrubbing system.

Klunder; ,Edgar B. (Bethel Park, PA)

2009-02-24T23:59:59.000Z

275

Morphological Investigations of Fibrogenic Action of Estonian Oil Shale Dust  

E-Print Network (OSTI)

dust produced in the mining and processing of Estonian oil shale is given. Histological examination of

V. A. Kung

276

Effect of lift force on the aerodynamics of dust grains in the protoplanetary disk  

E-Print Network (OSTI)

We newly introduce lift force into the aerodynamics of dust grains in the protoplanetary disk. Although many authors have so far investigated the effects of the drag force, gravitational force and electric force on the dust grains, the lift force has never been considered as a force exerted on the dust grains in the gas disk. If the grains are spinning and moving in the fluid, then the lift force is exerted on them. We show in this paper that the dust grains can be continuously spinning due to the frequent collisions so that the lift force continues to be exerted on them, which is valid in a certain parameter space where the grain size is larger than ~ 1 m and where the distance from the central star is larger than 1 AU for the minimum mass solar nebula. In addition, we estimate the effects of the force on the grain motion and obtain the result that the mean relative velocity between the grains due to the lift force is comparable to the gas velocity in the Kepler rotational frame when the Stokes number and li...

Yamaguchi, Masaki S

2014-01-01T23:59:59.000Z

277

Coal Fly Ash as a Source of Iron in Atmospheric Dust  

SciTech Connect

Anthropogenic coal fly ash aerosols may represent a significant source of bioavailable iron in the open ocean. Few measurements have been made to compare the solubility of atmospheric iron from anthropogenic aerosols and other sources. We report an investigation of the iron dissolution of three fly ash samples in acidic aqueous solutions and compare the solubilities with that of Arizona test dust, a reference material of mineral dust. The effects of pH, cloud processing, and solar irradiation on Fe solubility were explored. Similar to previously reported results on mineral dust, iron in aluminosilicate phases provide predominant dissolved iron compared with iron in oxides. Iron solubility of fly ash is higher than Arizona test dust, especially at the higher pH conditions investigated. Simulated atmospheric processing elevates iron solubility due to significant changes in the morphology aluminosilicate glass, a dominantly material in fly ash particle. Iron continuously releases into the aqueous solution as fly ash particles break up into smaller fragments. The assessment of dissolved atmospheric iron deposition fluxes, and their effect on the biogeochemistry at ocean surface should be constrained by taking into account the source, environment pH, Fe speciation, and solar radiation.

Chen, Haihan; Laskin, Alexander; Baltrusaitis, Jonas; Gorski, Christopher A.; Scherer, Michelle; Grassian, Vicki H.

2012-01-18T23:59:59.000Z

278

Cosmological acceleration from a gas of strings  

Science Journals Connector (OSTI)

In string gas cosmology, the extra dimensions of the underlying theory are kept at a microscopic scale by a gas of strings. In the matter-dominated era, however, dust pressure can lead to oscillations of the extra dimensions and to acceleration in the three visible dimensions, even with a vanishing cosmological term. We review the resulting oscillating expansion history, that provides an acceptable fit to the observed accelerated expansion of the Universe.

Francesc Ferrer

2009-01-01T23:59:59.000Z

279

Cosmological acceleration from a gas of strings  

E-Print Network (OSTI)

In string gas cosmology, the extra dimensions of the underlying theory are kept at a microscopic scale by a gas of strings. In the matter-dominated era, however, dust pressure can lead to oscillations of the extra dimensions and to acceleration in the three visible dimensions, even with a vanishing cosmological term. We review the resulting oscillating expansion history, that provides an acceptable fit to the observed accelerated expansion of the Universe.

Francesc Ferrer

2009-07-08T23:59:59.000Z

280

Measuring momentum for charged particle tomography  

DOE Patents (OSTI)

Methods, apparatus and systems for detecting charged particles and obtaining tomography of a volume by measuring charged particles including measuring the momentum of a charged particle passing through a charged particle detector. Sets of position sensitive detectors measure scattering of the charged particle. The position sensitive detectors having sufficient mass to cause the charged particle passing through the position sensitive detectors to scatter in the position sensitive detectors. A controller can be adapted and arranged to receive scattering measurements of the charged particle from the charged particle detector, determine at least one trajectory of the charged particle from the measured scattering; and determine at least one momentum measurement of the charged particle from the at least one trajectory. The charged particle can be a cosmic ray-produced charged particle, such as a cosmic ray-produced muon. The position sensitive detectors can be drift cells, such as gas-filled drift tubes.

Morris, Christopher (Los Alamos, NM); Fraser, Andrew Mcleod (Los Alamos, NM); Schultz, Larry Joe (Los Alamos, NM); Borozdin, Konstantin N. (Los Alamos, NM); Klimenko, Alexei Vasilievich (Maynard, MA); Sossong, Michael James (Los Alamos, NM); Blanpied, Gary (Lexington, SC)

2010-11-23T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Surface acoustic wave dust deposition monitor  

DOE Patents (OSTI)

A system is disclosed for using the attenuation of surface acoustic waves to monitor real time dust deposition rates on surfaces. The system includes a signal generator, a tone-burst generator/amplifier connected to a transmitting transducer for converting electrical signals into acoustic waves. These waves are transmitted through a path defining means adjacent to a layer of dust and then, in turn, transmitted to a receiving transducer for changing the attenuated acoustic wave to electrical signals. The signals representing the attenuated acoustic waves may be amplified and used in a means for analyzing the output signals to produce an output indicative of the dust deposition rates and/or values of dust in the layer. 8 figs.

Fasching, G.E.; Smith, N.S. Jr.

1988-02-12T23:59:59.000Z

282

Global coherence of dust density waves  

SciTech Connect

The coherence of self-excited three-dimensional dust density waves has been experimentally investigated by comparing global and local wave properties. For that purpose, three-dimensional dust clouds have been confined in a radio frequency plasma with thermophoretic levitation. Global wave properties have been measured from the line-of-sight integrated dust density obtained from homogenous light extinction measurements. Local wave properties have been obtained from thin, two-dimensional illuminated laser slices of the cloud. By correlating the simultaneous global and local wave properties, the spatial coherence of the waves has been determined. We find that linear waves with small amplitudes tend to be fragmented, featuring an incoherent wave field. Strongly non-linear waves with large amplitudes, however, feature a strong spatial coherence throughout the dust cloud, indicating a high level of synchronization.

Killer, Carsten; Melzer, André [Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, 17489 Greifswald (Germany)

2014-06-15T23:59:59.000Z

283

Radioactive contamination of atmospheric dust over southeastern New Mexico  

Science Journals Connector (OSTI)

Aerosol particle samples were collected at three sites located near the Waste Isolation Pilot Plant (WIPP), a deep underground nuclear waste-storage facility, and they were analyzed to investigate the spatial and temporal variations in the concentrations of selected radionuclides and inorganic substances. The activities of 238Pu, 239,240Pu,241Pu and 241Am were determined by alpha spectrometry following a series of chemical separations, and the concentrations of Al, U and Th were determined in a separate set of samples by inductively-coupled plasma mass spectrometry. There was no evidence for impacts of the WIPP on radionuclide activity concentrations. Rather, the activities of both naturally-occurring (U and Th) and man-made (241Am and 239,240Pu) radionuclides in the aerosols peaked in spring and tracked the loadings of Al, an indicator of mineral dust. More than half of the variability in the 239,240Pu at the sampling site closest to the WIPP could be explained by the seasonal cycles of atmospheric dust. For U and Th, the predictive value of Al was even higher: 66% to over 90% of the variance in these nuclides could be explained by their relationship to dust. Extrapolation of the data to a global scale suggests that ?0.02% of the total 239,240Pu from nuclear weapons’ fallout currently recirculates between the earth and atmosphere each year. In terms of monitoring releases from nuclear facilities, the results presented here demonstrate that elemental data provide information directly relevant to understanding causes for variability in the activities of atmospheric radionuclides.

Richard Arimoto; Joel L. Webb; Marsha Conley

2005-01-01T23:59:59.000Z

284

Thermo-Oxidation of Tokamak Carbon Dust  

SciTech Connect

The oxidation of dust and flakes collected from the DIII-D tokamak, and various commercial dust specimens, has been measured at 350 ºC and 2.0 kPa O2 pressure. Following an initial small mass loss, most of the commercial dust specimens showed very little effect due to O2 exposure. Similarly, dust collected from underneath DIII-D tiles, which is thought to comprise largely Grafoil™ particulates, also showed little susceptibility to oxidation at this temperature. However, oxidation of the dust collected from tile surfaces has led to ~ 18% mass loss after 8 hours; thereafter, little change in mass was observed. This suggests that the surface dust includes some components of different composition and/or structure – possibly fragments of codeposited layers. The oxidation of codeposit flakes scraped form DIII-D upper divertor tiles showed an initial 25% loss in mass due to heating in vacuum, and the gradual loss of 30-38% mass during the subsequent 24 hours exposure to O2. This behavior is significantly different from that observed for the oxidation of thinner DIII-D codeposit specimens which were still adhered to tile surfaces, and this is thought to be related to the low deuterium content (D/C ~ 0.03 – 0.04) of the flakes.

J.W. Davis; B.W.N. Fitzpatrick; J.P. Sharpe; A.A. Haasz

2008-04-01T23:59:59.000Z

285

Nano- and microscale particles and global electromagnetic resonances in the Earth-ionosphere cavity  

SciTech Connect

The influence of nano-and microscale particles (dust grains) on the global electromagnetic (Schumann) cavity has been studied in the context of two possible mechanisms. First, the presence of charged microscale particles in the ionospheric plasma modifies the dispersion properties of the upper boundary of the Schumann cavity and, thus, affects its eigenfrequencies and quality factor. Second, there is a relation between the dust concentration in the atmosphere and lightning discharges, which excite Schumann resonances. Therefore, dust grains can enhance the energy pumping of the cavity, thereby increasing the amplitude of electromagnetic oscillations in it.

Besedina, Yu. N.; Popel, S. I. [Russian Academy of Sciences, Institute of Geosphere Dynamics (Russian Federation)

2007-02-15T23:59:59.000Z

286

Quantitative organic vapor-particle sampler  

DOE Patents (OSTI)

A quantitative organic vapor-particle sampler for sampling semi-volatile organic gases and particulate components. A semi-volatile organic reversible gas sorbent macroreticular resin agglomerates of randomly packed microspheres with the continuous porous structure of particles ranging in size between 0.05-10 .mu.m for use in an integrated diffusion vapor-particle sampler.

Gundel, Lara (Berkeley, CA); Daisey, Joan M. (Walnut Creek, CA); Stevens, Robert K. (Cary, NC)

1998-01-01T23:59:59.000Z

287

Dustbuster: a compact impact-ionization time-of-flight mass spectrometer for in situ analysis of cosmic dust  

E-Print Network (OSTI)

a large target area with a reflectron, simultaneously optimizing mass resolution, particle detection. The resulting ions, with broad energy and angular distributions, are accelerated through a modified reflectron remote sensing, collection and analysis of dust grains that have survived impact on the Earth, capture

Stewart, Sarah T.

288

Quenching dust mixtures: A new microgravity testing method using electric particulate suspensions  

SciTech Connect

The electric particulate suspension (EPS) is a combustion ignition system under development at Iowa State University for the evaluation of quenching effects of powders in microgravity (quenching distance, ignition energy, and flammability limits). Both walls and (inert) particles can be tested as quenching media. The EPS method has potential as a benchmark design for quenching powder flames that would provide NASA and the scientific community with a new fire safety standard. Because of its simplicity and size, it is also suitable for tests on the International Space Station and the Mars Rover. The EPS method also supports combustion modeling by providing accurate measurement of flame-quenching distance as an important parameter in laminar flame theory because it is closely related to characteristic flame thickness and flame structure. In microgravity, the EPS method is expected to produce dust suspensions that are highly uniform (before ignition) compared to 1-g, where gravity can cause stratification of the suspension. Microgravity will also permit increased concentrations of particles to be tested (for a given electric field strength). Several EPS experiments are reviewed, including X-Y laser scans for cloud stratification, particle velocity distribution evaluation by the use of particle tracking velocimetry/particle image velocimetry and a leak hole sampling rig, and measurement of particle slip velocity by the use of laser Doppler anemometry. Sample quenching and ignition energy curves are presented for aluminum powder and coal dust. Only ground-based data at 1-g are reported.

Colver, G.M.; Greene, N.; Shoemaker, D.; Kim, S.W.; Yu, T.U. [Iowa State University, Ames, IA (US). Dept. of Mechanical Engineering

2004-10-15T23:59:59.000Z

289

Dust Grain-Size Distributions From MRN to MEM  

E-Print Network (OSTI)

Employing the Maximum Entropy Method algorithm, we fit interstellar extinction measurements which span the wavelength range 0.125-3 micron. We present a uniform set of MEM model fits, all using the same grain materials, optical constants and abundance constraints. In addition, we are taking advantage of improved UV and IR data and better estimates of the gas-to-dust ratio. The model fits cover the entire range of extinction properties that have been seen in the Galaxy and the Magellanic Clouds. The grain models employed for this presentation are the simplistic homogeneous spheres models (i.e., Mathis, Rumpl, & Nordsieck 1977) with two (graphite, silicate) or three (graphite, silicate, amorphous carbon) components. Though such usage is only a first step, the results do provide interesting insight into the use of grain size as a diagnostic of dust environment. We find that the SMC Bar extinction curve cannot be fit using carbon grains alone. This is a challenge to the recent observational result indicating little silicon depletion in the SMC.

Geoffrey C. Clayton; Michael J. Wolff; Ulysses J. Sofia; K. D. Gordon; K. A. Misselt

2003-01-24T23:59:59.000Z

290

BNL-67852-AB CHARACTERIZATION OF ORGANICS IN ATMOSPHERIC PARTICLES BY SINGLE  

E-Print Network (OSTI)

of aerosol or aerosol precursors, particle formation (gas to particle conversion), and growth is critical to a significant fraction of the total aerosol mass (often between 20 and 50%) and play an important role tend to be governed by complex gas - particle and particle - particle interactions, produce a rich

291

Propagation of dust-acoustic waves in a bounded dusty plasma  

Science Journals Connector (OSTI)

The linear and nonlinear propagation of dust-acoustic waves in a dusty plasma bounded in finite geometry has been theoretically investigated. It is found that the finite geometry of the bounded plasma makes a significant contribution to the instability of the wave. Moreover, the pseudopotential has a positive and inverted profile that prevents the trapping of particles and does not favor solitary waves in bounded dusty plasma.

Kalyan Kr. Mondal; A. Roychowdhury; S. N. Paul

2001-12-14T23:59:59.000Z

292

E-Print Network 3.0 - atmospheric dust dispersion Sample Search...  

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

residence time of the dust in the atmosphere... - tribution of dust transport and resuspension to particulate matter levels in the Mediterranean atmosphere... ), Saharan dust in...

293

E-Print Network 3.0 - age-dependent dust heating Sample Search...  

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

12;Dust-induced increase... of dust-induced heating was balanced by surface turbulent heat loss, vertical mixing, horizontal transport... model, the dust-induced increase in...

294

Hot Coal for Christmas: Dust Formation in the Swept-Up Shell Around The Peculiar Type Ib Supernova 2006jc  

E-Print Network (OSTI)

We present evidence for the formation of dust grains in an unusual Type Ib SN based on late-time spectra of SN 2006jc. The progenitor suffered a giant outburst qualitatively similar to those seen in LBVs just 2 years prior to the SN, and we speculate that the dust formation we observe is an indirect consequence of that event. The key evidence for dust formation seen in our optical spectra is (1) the appearance of a strong continuum emission source at red wavelengths, and (2) fading of the redshifted sides of narrow HeI emission lines. These two observed characteristics provide the strongest case yet for dust formation in any Type Ib/c SN. Both developments occurred simultaneously between 51 and 75 days after peak brightness, which is quick compared to other dusty SNe. The high temperature of the dust implies carbon and not silicates, and we describe how infrared photometry may test this conjecture. Geometric considerations indicate dust formation occurring in the dense gas swept-up by the forward shock, and n...

Smith, Nathan; Filippenko, Alexei V

2007-01-01T23:59:59.000Z

295

Beam-Gas  

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

Gas Gas and Thermal Photon Scattering in the NLC Main Linac as a Source of Beam Halo P. Tenenbaum LCC-Note-0051 12-JAN-2001 Abstract Scattering of primary beam electrons off of residual gas molecules or blackbody radiation photons in the NLC main linac has been identified as a potential source of beam haloes which must be collimated in the beam delivery system. We consider the contributions from four scat- tering mechanisms: inelastic thermal-photon scattering, elastic beam-gas (Coulomb) scattering inelastic beam-gas (Bremsstrahlung) scattering, and atomic-electron scattering. In each case we develop the formalism necessary to estimate the backgrounds generated in the main linac, and determine the expected number of off-energy or large-amplitude particles from each process, assuming a main linac injection energy of 8 GeV and extraction energy of 500 GeV. 1 Introduction The

296

U-GAS process  

SciTech Connect

The Institute of Gas Technology (IGT) has developed an advanced coal gasification process. The U-GAS process has been extensively tested in a pilot plant to firmly establish process feasibility and provide a large data base for scale-up and design of the first commercial plant. The U-GAS process is considered to be one of the more flexible, efficient, and economical coal gasification technologies developed in the US during the last decade. The U-GAS technology is presently available for licensing from GDC, Inc., a wholly-owned subsidiary of IGT. The U-GAS process accomplishes four important functions in a single-stage, fluidized-bed gasifier: It decakes coal, devolatilizes coal, gasifies coal, and agglomerates and separates ash from char. Simultaneously with coal gasification, the ash is agglomerated into spherical particles and separated from the bed. Part of the fluidizing gas enters the gasifier through a sloping grid. The remaining gas flows upward at a high velocity through the ash agglomerating device and forms a hot zone within the fluidized bed. High-ash-content particles agglomerate under these conditions and grow into larger and heavier particles. Agglomerates grow in size until they can be selectively separated and discharged from the bed into water-filled ash hoppers where they are withdrawn as a slurry. In this manner, the fluidized bed achieves the same low level of carbon losses in the discharge ash generally associated with the ash-slagging type of gasifier. Coal fines elutriated from the fluidized bed are collected in two external cyclones. Fines from the first cyclone are returned to the bed and fines from the second cyclone are returned to the ash agglomerating zone, where they are gasified, and the ash agglomerated with bed ash. The raw product gas is virtually free of tar and oils, thus simplifying ensuing heat recovery and purification steps.

Schora, F.C.; Patel, J.G.

1982-01-01T23:59:59.000Z

297

Particle Lifetimes  

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

Reviewing Particle Lifetimes Reviewing Particle Lifetimes The lifetimes of elementary particles are statistical in nature. In a given sample, one particle might decay immediately, another in 1 nanosecond, yet another after 10 milliseconds, and still another in 50 years. What we call the lifetime is the time it takes for a sample to decay so 1/e (~30%) of the sample is left; after 2 lifetimes, 1/e2 of the sample is left, and so on. Take, for example, a sample of cosmic ray muons produced in the upper atmosphere. These muons, when observed at (relative) rest in the laboratory, have a mean lifetime T. Now, since particle decay is statistical in nature, the number of undecayed particles after a given time is a negative exponential function: N(t) = No e-t/T where N(t) is the number of muons at time t, No is the initial number of

298

Numerical Simulation of Dust in a Cometary Coma: Application to Comet 67P/Churyumov-Gerasimenko  

Science Journals Connector (OSTI)

The Rosetta spacecraft is en route to comet 67P/Churyumov-Gerasimenko for a rendezvous, landing, and extensive orbital phase beginning in 2014. With a limited amount of available observational data, planning of the mission as well as the interpretation of measurements obtained by instruments on board the spacecraft requires modeling of the dusty/gas environment of the comet. During the mission, the collision regime in the inner coma will change starting from transitional to fully collisionless. As a result, a physically correct model has to be valid at conditions that are far from equilibrium and account for the kinetic nature of the processes occurring in the coma. A study of the multi-species coma of comet 67P/Churyumov-Gerasimenko is presented in our previous paper, where we describe our kinetic model and discuss the results of its application to cases that correspond to the different stages during the mission. In this work, we focus on numerical modeling of the dust phase in the coma of comet 67P/Churyumov-Gerasimenko and its interaction with the surrounding gas. The basic phenomena that govern the dynamics and energy balance of the dust grains are outlined. The effect of solar radiation pressure and the nucleus gravity in limiting the maximum liftable mass of the grains is discussed. The distribution of the terminal velocity of the dust grains as a function of subsolar angle is derived in the paper. We have found that in the regions with high gradients of the gas density, spike-like features can form in the dust flow. The obtained results represent the state of the coma in the vicinity of the nucleus for a series of stages throughout the Rosetta mission. The implications of the model results for future measurements by the GIADA instrument are discussed.

Valeriy Tenishev; Michael R. Combi; Martin Rubin

2011-01-01T23:59:59.000Z

299

Cold condensation of dust in the ISM  

E-Print Network (OSTI)

The condensation of complex silicates with pyroxene and olivine composition at conditions prevailing in molecular clouds has been experimentally studied. For this purpose, molecular species comprising refractory elements were forced to accrete on cold substrates representing the cold surfaces of surviving dust grains in the interstellar medium. The efficient formation of amorphous and homogeneous magnesium iron silicates at temperatures of about 12 K has been monitored by IR spectroscopy. The gaseous precursors of such condensation processes in the interstellar medium are formed by erosion of dust grains in supernova shock waves. In the laboratory, we have evaporated glassy silicate dust analogs and embedded the released species in neon ice matrices that have been studied spectroscopically to identify the molecular precursors of the condensing solid silicates. A sound coincidence between the 10 micron band of the interstellar silicates and the 10 micron band of the low-temperature siliceous condensates can be...

Rouillé, Gaël; Krasnokutski, Serge A; Krebsz, Melinda; Henning, Thomas

2015-01-01T23:59:59.000Z

300

Mass production of multi-wall carbon nanotubes by metal dusting process with high yield  

SciTech Connect

Research highlights: {yields} Synthesis of carbon nanotubes over Fe-Ni nanoparticles supported alloy 304L. {yields} Production of carbon nanotubes with high yield (700-1000%) and low cost catalyst. {yields} Optimum growth condition is CO/H{sub 2} = 1/1, 100 cm{sup 3}/min, at 620 {sup o}C under long term repetitive thermal cycling. {yields} Possibility of the mass production by metal dusting process with low cost. -- Abstract: Carbon nanotube materials were synthesized over Fe-Ni nanoparticles generated during disintegration of the surface of alloy 304L under metal dusting environment. The metal dusting condition was simulated and optimized through exposing stainless steel samples during long term repetitive thermal cycling in CO/H{sub 2} = 1/1, total gas flow rate 100 cm{sup 3}/min, at 620 {sup o}C for 300 h. After reaction, surface morphology of the samples and also carbonaceous deposition which had grown on sample surfaces were examined by stereoscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results revealed that multi-wall carbon nanotubes could be formed over nanocatalyst generated on the alloy surface by exploiting metal dusting process. By optimization of reaction parameters the yields of carbon nanotube materials obtained were 700-1000%. Also it has been shown herein that the amount of carbon nanotube materials remarkably increases when the reaction time is extended up to 300 h, indicating a possibility of the mass production by this easy method.

Ghorbani, H. [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of)] [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of); Rashidi, A.M., E-mail: Rashidiam@ripi.ir [Nanotechnology Research Center, Research Institute of Petroleum Industry (RIPI), West Blvd. Azadi Sport Complex, P.O. Box 14665-1998, Tehran (Iran, Islamic Republic of); Rastegari, S.; Mirdamadi, S. [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of)] [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of); Alaei, M. [Nanotechnology Research Center, Research Institute of Petroleum Industry (RIPI), West Blvd. Azadi Sport Complex, P.O. Box 14665-1998, Tehran (Iran, Islamic Republic of)] [Nanotechnology Research Center, Research Institute of Petroleum Industry (RIPI), West Blvd. Azadi Sport Complex, P.O. Box 14665-1998, Tehran (Iran, Islamic Republic of)

2011-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Solar Dust Ring Observation At The Total Solar Eclipse In Mexico  

Science Journals Connector (OSTI)

There are dust grains in interplanetary space. Zodiacal light observations show a distribution of dust grains in the ecliptic plane, but cannot show how close to the Sun dust grains survive. Dust grains close ...

Syuzo Isobe; Toshihiko Tanabe…

1992-01-01T23:59:59.000Z

302

THE DUST PROPERTIES OF z {approx} 3 MIPS-LBGs FROM PHOTOCHEMICAL MODELS  

SciTech Connect

The stacked spectral energy distribution (SED) 24 {mu}m Lyman break galaxies (MIPS-LBGs) detected by the Multiband Imaging Photometer for Spitzer (MIPS) is fitted by means of the spectrophotometric model GRASIL with an ''educated'' fitting approach which benefits from the results of chemical evolution models. The star formation rate-age-metallicity degeneracies of SED modeling are broken by using star formation history (SFH) and chemical enrichment history suggested by chemical models. The dust mass, dust abundance, and chemical pattern of elements locked in the dust component are also directly provided by chemical models. Using our new ''fitting'' approach, we derive the total mass M{sub tot}, stellar mass M{sub *}, gas mass M{sub g} , dust mass M{sub d} , age, and star formation rate (SFR) of the stacked MIPS-LBG in a self-consistent way. Our estimate of M{sub *} = 8 Multiplication-Sign 10{sup 10} of the stacked MIPS-LBG agrees with other works based on UV-optical SED fitting. We suggest that the MIPS-LBGs at z {approx} 3 are young (0.3-0.6 Gyr), massive (M{sub tot} {approx} 10{sup 11} M{sub Sun }), dusty (M{sub d} {approx} 10{sup 8} M{sub Sun }), and metal-rich (Z {approx} Z{sub Sun }) progenitors of elliptical galaxies undergoing a strong burst of star formation (SFR {approx} 200 M{sub Sun} yr{sup -1}). Our estimate of M{sub d} = 7 Multiplication-Sign 10{sup 7} M{sub Sun} of the stacked MIPS-LBG is about a factor of eight lower than the estimated value based on single temperature graybody fitting, suggesting that self-consistent SED models are needed to estimate dust mass. By comparing with Milky Way molecular cloud and dust properties, we suggest that denser and dustier environments and flatter dust size distribution are likely in high-redshift massive star-forming galaxies. These dust properties, as well as the different types of SFHs, can cause different SED shapes between high-redshift star-forming ellipticals and local starburst templates. This discrepancy of SED shapes could in turn explain the non-detection at submillimeter wavelengths of IR luminous (L{sub IR} Succeeds-Above-Single-Line-Equals-Sign 10{sup 12} L{sub Sun }) MIPS-LBGs.

Fan, X. L. [School of Physics and Electronics Information, Hubei University of Education, 430205 Wuhan (China); Pipino, A. [Institut fur Astronomie, ETH Zurich, CH-8093 Zurich (Switzerland); Matteucci, F., E-mail: fan@oats.inaf.it [Dipartimento di Fisica, Sezione di Astronomia, Universit a di Trieste, via G.B. Tiepolo 11, I-34131 Trieste (Italy)

2013-05-10T23:59:59.000Z

303

Natural Gas  

Science Journals Connector (OSTI)

30 May 1974 research-article Natural Gas C. P. Coppack This paper reviews the world's existing natural gas reserves and future expectations, together with natural gas consumption in 1972, by main geographic...

1974-01-01T23:59:59.000Z

304

airborne respirable dust: Topics by E-print Network  

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

Distributed Sensor Networks and Ad-hoc Networking 4 1.2.2 High Level Interpretation of Spatial Sensor Data 4 1.2.3 Distributed Processing 5 1.2.4 COTS Dust 6 2.0 COTS Dust...

305

Lunar Atmosphere and Dust Environment Explorer Frequently Asked Questions  

E-Print Network (OSTI)

LADEE Lunar Atmosphere and Dust Environment Explorer Frequently Asked Questions What mystery: was lunar dust, electrically charged by solar ultraviolet light, responsible for the presunrise of space exploration through our expertise in science, engineering, mission operations, and data management

Mojzsis, Stephen J.

306

The Dust Explosion Characteristics of Coal Dust in an Oxygen Enriched Atmosphere  

Science Journals Connector (OSTI)

The ability to mix pulverised coal with oxygen at concentrations greater than the currently applied 21% may well provide advantages for burner design in oxy/coal fired systems. However the risk of dust explosions increases significantly with increasing oxygen concentration and temperature. In this study the influence of enriched oxygen concentrations is researched on the dust explosion characteristics of Indonesian (Sebuku) high volatile bituminous coal dust and on Pittsburgh Coal n¡8. Both ignition sensitivity characteristics (minimum ignition energy and minimum ignition temperatures) and explosion severity characteristics (maximum explosion pressure, Pmax, and maximum rate of pressure rise, Kst) are investigated.

Frederik Norman; Jan Berghmans; Filip Verplaetsen

2012-01-01T23:59:59.000Z

307

Cold Gas Traps for Ice Particle Formation  

Science Journals Connector (OSTI)

...GKSS-Forschungszentrum, Max-Planck-Strasse 1, D-21502 Geesthacht, Germany. Water, with the characteristic angular structure...GKSS-Forschungszentrum, Max-Planck-Strabetae 1, D-21502 Geesthacht, Germany. *To whom correspondence should be addressed...

S. Bauerecker; B. Neidhart

1998-12-18T23:59:59.000Z

308

Colloidal particle-surface interactions in atmospheric and aquatic systems.  

E-Print Network (OSTI)

??Colloidal particles suspended in a liquid or gas phase often interact with a solid-liquid or solid-gas interface. In this study, experimental data through atomic force… (more)

Chung, Eunhyea

2011-01-01T23:59:59.000Z

309

Water adsorption on aggregates of spherical aerosol nano particles  

E-Print Network (OSTI)

graphite planer substrate; the result corresponds well with previous simulation work. Adsorption of both noble gas and water onto a single spherical nano particle and aggregates of spherical nano particles has been computed with the developed equation...

Nie, Chu

2005-11-01T23:59:59.000Z

310

Simple Cosmological Model with Relativistic Gas  

E-Print Network (OSTI)

We construct simple and useful approximation for the relativistic gas of massive particles. The equation of state is given by an elementary function and admits analytic solution of the Friedmann equation, including more complex cases when the relativistic gas of massive particles is considered together with radiation or with dominating cosmological constant. The model of relativistic gas may be interesting for the description of primordial Universe, especially as a candidate for the role of a Dark Matter.

Guilherme de Berredo-Peixoto; Ilya L. Shapiro; Flavia Sobreira

2005-06-16T23:59:59.000Z

311

484 2009 ASHRAE Recently, the interaction between particles retained on  

E-Print Network (OSTI)

484 ©2009 ASHRAE ABSTRACT Recently, the interaction between particles retained on HVAC filters outcomes,and odors.Thispaperfocusesonmicrobialcontam- inants and metals captured on HVAC filters in nine at the time of sampling. HVAC filter dust is a potential resource that has received less attention and may

Siegel, Jeffrey

312

An Alternate Approach to Determine the Explosibility of Dusts  

E-Print Network (OSTI)

dust cloud; a 10,000 Joule (10 kJ) flame is subsequently forced through the dust cloud and the resulting pressure rise is measured. If the pressure rise exceeds one bar (14.5 psig), it is assumed that a deflagration occurred, and the dust is classified...

Ganesan, Balaji

2013-12-04T23:59:59.000Z

313

Gas fluidized-bed stirred media mill  

DOE Patents (OSTI)

A gas fluidized-bed stirred media mill is provided for comminuting solid ticles. The mill includes a housing enclosing a porous fluidizing gas diffuser plate, a baffled rotor and stator, a hollow drive shaft with lateral vents, and baffled gas exhaust exit ports. In operation, fluidizing gas is forced through the mill, fluidizing the raw material and milling media. The rotating rotor, stator and milling media comminute the raw material to be ground. Small entrained particles may be carried from the mill by the gas through the exit ports when the particles reach a very fine size.

Sadler, III, Leon Y. (Tuscaloosa, AL)

1997-01-01T23:59:59.000Z

314

"Separations: Dust to Dust" or " You Can't Escape Em"  

E-Print Network (OSTI)

"SEPARATIONS: DUST TO DUST" OR "YOU CAN'T ESCAPE EM" Robert G. Massey Office of Industrial Programs U.S. Dept. of Energy ABSTRACT Separations are recognized by industry as one of the larger, if not the largest, energy using processes... are used to separate mixtures into their components. Three projects of the Office of Industrial Programs, Department of Energy illustrate these categories. Moltox is an air separation process based on the oxidation/reduction equilibrium of molten alkali...

Massey, R. G.

315

Initiation of weak coal-dust explosions in long galleriesand the importance of the time dependence of the explosion pressure  

Science Journals Connector (OSTI)

Weak coal-dust explosions in galleries (large horizontal tubes) are defined in the paper asthe early stages of what may eventually become a self-sustaining, steady-state situation, if the scale is large enough. An initiating explosion producing a pressure rise of at least 12 kPa is needed to start an explosion from any additional dust that lies beyond the initiating zone; entrainment of this additional dust leads to the main explosion. In long galleries, initiating explosions in the range 16±2 kPa are mostly used. The early stages of the main explosion resemble explosions in which combustion of a very low concentration of coal-dust particles is taking place over a considerable volume at any given time, rather than explosions in which a flame, having a more or less definable front and rear, is propagating through a preformed explosive mixture. The explosions are described in terms of the general shape of the pressure changes occurring at a point near the outermost extent of the flame that is produced by the initiation explosion alone. The initial pressure rise is determined by the form of the initiating explosion and is followed by a roughly exponential pressure increase (from atmospheric pressure), whose time constant depends on the nature of the coal-dust, its dispersion, and the dimensions and characteristics of the gallery. The effects on the development of the explosion of the presence of short dust deposits, suppressive devices, and the ignition of predispersed clouds are briefly discussed. It is concluded that, in weak explosions, propagation results from dust being swept from the floor into the zone of combustion behind the flame front. However, as pressures increase to above, say, 100 kPa, other mechanisms become responsible and, perhaps, a pre-detonation regime sets in.

D. Rae

1973-01-01T23:59:59.000Z

316

Arbitrary amplitude dust ion acoustic solitary waves in a magnetized suprathermal dusty plasma  

SciTech Connect

The linear and nonlinear dust-ion-acoustic (DIA) wave propagating obliquely with respect to an external magnetic field is studied in a magnetized complex plasma which consists of a cold ion fluid, superthermal electrons, and static dust particles. The propagation properties of two possible modes (in the linear regime) are investigated. It is found that the electron suprathermality and the electron population decrease the phase velocities of both modes, while obliqueness leads to increase of separation between two modes. An energy-like equation derived to describe the nonlinear evolution of DIA solitary waves. The influences of electron suprathermality, obliqueness, and electron population on the existence domain of solitary waves and the soliton characteristics are examined. It is shown that the existence domain of the DIA soliton and its profile are significantly depending on the deviation of electrons from thermodynamic equilibrium, electrons population, and obliqueness. It is also found that the suprathermal plasma supports the DIA solitons with larger amplitude.

Shahmansouri, M. [Department of Physics, Faculty of Science, Arak University, Arak 38156-8-8349 (Iran, Islamic Republic of); Alinejad, H. [Department of Physics, Faculty of Basic Science, Babol University of Technology, Babol 47148-71167, Iran and Research Institute for Astronomy and Astrophysics of Maragha (RIAAM), P.O. Box 55134-441, Maragha (Iran, Islamic Republic of)

2012-12-15T23:59:59.000Z

317

NATURAL GAS FROM SHALE: Questions and Answers Shale Gas Development Challenges -  

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

Air Air Key Points: * Air quality risks from shale oil and gas development are generally the result of: (1) dust and engine exhaust from increased truck traffic; (2) emissions from diesel-powered pumps used to power equipment; (3) intentional flaring or venting of gas for operational reasons; and, (4) unintentional emissions of pollutants from faulty equipment or impoundments. 1 * Natural gas is efficient and clean compared to other fossil fuels, emitting less nitrogen oxide and sulfur dioxide than coal and oil, no mercury and very few particulates. However, the drilling

318

REVIEW OF PARTICLE PHYSICS  

E-Print Network (OSTI)

ONLINE PARTICLE PHYSICS INFORMATION 1.3. Particle Physics Information Platforms . . . . . . . . .14. Particle Physics Education and Outreach

Beringer, Juerg

2013-01-01T23:59:59.000Z

319

Review of Particle Physics  

E-Print Network (OSTI)

11. Particle Physics Education Sites . . . . . . . . .ONLINE PARTICLE PHYSICS INFORMATION 1.11. Particle Physics Education Sites . . . . . . . . . . 12.

Nakamura, Kenzo

2010-01-01T23:59:59.000Z

320

Trillion Particles,  

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

Trillion Trillion Particles, 120,000 cores, and 350 TBs: Lessons Learned from a Hero I/O Run on Hopper Surendra Byna ∗ , Andrew Uselton ∗ , Prabhat ∗ , David Knaak † , and Yun (Helen) He ∗ ∗ Lawrence Berkeley National Laboratory, USA. Email: {sbyna, acuselton, prabhat, yhe}@lbl.gov † Cray Inc., USA. Email: knaak@cray.com Abstract-Modern petascale applications can present a variety of configuration, runtime, and data management challenges when run at scale. In this paper, we describe our experiences in running VPIC, a large-scale plasma physics simulation, on the NERSC production Cray XE6 system Hopper. The simulation ran on 120,000 cores using ∼80% of computing resources, 90% of the available memory on each node and 50% of the Lustre scratch file system. Over two trillion particles were simulated for 23,000 timesteps, and 10 one-trillion particle dumps, each ranging between

Note: This page contains sample records for the topic "dust particles gas" 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

Elementary Particles  

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

Elementary Particles Elementary Particles Elementary Particles Detectors Accelerators Visit World Labs For Children - for younger people Electric Forces & Fields For Children The Electric Force For Children Electric Force Fields For Children Charges and Fields For Children Vibrating Charges and Electromagnetic Waves Electrons For Older People The Discovery of the Electron Traveling Waves For Older People Waves and Wave-Like Motion For Children Catch the Wave For Children Vibrating Charges and Electromagnetic Waves For Children Electromagnetic Waves Standing Waves For Older People Physics 128 Lecture Standing Waves For Older People Resonance in Strings and Springs For Older People Standing Wave - 1st Harmonic For Older People Standing Wave - 2nd Harmonic Atom For Older People Bohr Atom

322

Gas Turbines  

Science Journals Connector (OSTI)

When the gas turbine generator was introduced to the power generation ... fossil-fueled power plant. Twenty years later, gas turbines were established as an important means of ... on utility systems. By the early...

Jeffrey M. Smith

1996-01-01T23:59:59.000Z

323

Gas Turbines  

Science Journals Connector (OSTI)

... the time to separate out the essentials and the irrelevancies in a text-book. The gas ...gasturbine ...

H. CONSTANT

1950-10-21T23:59:59.000Z

324

NATURAL GAS FROM SHALE: Questions and Answers  

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

Challenges are Associated with Challenges are Associated with Shale Gas Production? Developing any energy resource - whether conventional or non-conventional like shale - carries with it the possibility and risk of environmental, public health, and safety issues. Some of the challenges related to shale gas production and hydraulic fracturing include: * Increased consumption of fresh water (volume and sources); * Induced seismicity (earthquakes) from shale flowback water disposal;Chemical disclosure of fracture fluid additives; * Potential ground and surface water contamination; * Air quality impacts; * Local impacts, such as the volume of truck traffic, noise, dust and land disturbance.

325

Differences in pulmonary responses of rats, other animals, and humans to chronic inhalation of silica and other particles  

SciTech Connect

The pulmonary carcinogenicity of quartz in rats supports the plausibility of silica-induced lung cancer in humans. However, pulmonary responses of rats to dusts differ from those of other rodents, and may differ from those of humans. Dust-exposed rats have a greater propensity than mice or hamsters for epithelial hyperplasia, metaplasia, and fibrosis. Lung tumors occur in rats, but not mice or hamsters, treated with quartz, or exposed chronically to several other dusts. There are few opportunities for directly comparing the susceptibilities of rats and humans to dust-induced lung tumors. Because of the uncertain human responses to silica and many other particles, the negative human lung cancer response to coal dust may provide the best opportunity to calibrate responses of rats against those of humans. Historical dust lung burdens in coal miners were in the range of those associated with carcinogenicity in rats exposed to several dusts, but the carcinogenicity of coal dust in rats is unknown. The usefulness of tumor data from rats for predicting human lung cancer risk from inhaled silica and other dusts remains uncertain.

Mauderly, J.L.

1993-12-31T23:59:59.000Z

326

Technology Assessment of Dust Suppression Techniques Applied During Structural Demolition  

SciTech Connect

Hanford, Fernald, Savannah River, and other sites are currently reviewing technologies that can be implemented to demolish buildings in a cost-effective manner. In order to demolish a structure properly and, at the same time, minimize the amount of dust generated from a given technology, an evaluation must be conducted to choose the most appropriate dust suppression technology given site-specific conditions. Thus, the purpose of this research, which was carried out at the Hemispheric Center for Environmental Technology (HCET) at Florida International University, was to conduct an experimental study of dust aerosol abatement (dust suppression) methods as applied to nuclear D and D. This experimental study targeted the problem of dust suppression during the demolition of nuclear facilities. The resulting data were employed to assist in the development of mathematical correlations that can be applied to predict dust generation during structural demolition.

Boudreaux, J.F.; Ebadian, M.A.; Williams, P.T.; Dua, S.K.

1998-10-20T23:59:59.000Z

327

Experimental investigation on an entrained flow type biomass gasification system using coconut coir dust as powdery biomass feedstock  

Science Journals Connector (OSTI)

Based on an entrained flow concept, a prototype atmospheric gasification system has been designed and developed in the laboratory for gasification of powdery biomass feedstock such as rice husks, coconut coir dust, saw dust etc. The reactor was developed by adopting L/D (height to diameter) ratio of 10, residence time of about 2 s and a turn down ratio (TDR) of 1.5. The experimental investigation was carried out using coconut coir dust as biomass feedstock with a mean operating feed rate of 40 kg/h The effects of equivalence ratio in the range of 0.21–0.3, steam feed at a fixed flow rate of 12 kg/h, preheat on reactor temperature, product gas yield and tar content were investigated. The gasifier could able to attain high temperatures in the range of 976–1100 °C with gas lower heating value (LHV) and peak cold gas efficiency (CGE) of 7.86 MJ/Nm3 and 87.6% respectively.

P.K. Senapati; S. Behera

2012-01-01T23:59:59.000Z

328

Colorado Natural Gas Number of Gas and Gas Condensate Wells ...  

Annual Energy Outlook 2012 (EIA)

Gas and Gas Condensate Wells (Number of Elements) Colorado Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

329

California Natural Gas Number of Gas and Gas Condensate Wells...  

Annual Energy Outlook 2012 (EIA)

Gas and Gas Condensate Wells (Number of Elements) California Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4...

330

Louisiana Natural Gas Number of Gas and Gas Condensate Wells...  

U.S. Energy Information Administration (EIA) Indexed Site

Gas and Gas Condensate Wells (Number of Elements) Louisiana Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

331

Michigan Natural Gas Number of Gas and Gas Condensate Wells ...  

Annual Energy Outlook 2012 (EIA)

Gas and Gas Condensate Wells (Number of Elements) Michigan Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

332

Oklahoma Natural Gas Number of Gas and Gas Condensate Wells ...  

U.S. Energy Information Administration (EIA) Indexed Site

Gas and Gas Condensate Wells (Number of Elements) Oklahoma Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

333

Virginia Natural Gas Number of Gas and Gas Condensate Wells ...  

Annual Energy Outlook 2012 (EIA)

Gas and Gas Condensate Wells (Number of Elements) Virginia Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

334

Tennessee Natural Gas Number of Gas and Gas Condensate Wells...  

U.S. Energy Information Administration (EIA) Indexed Site

Gas and Gas Condensate Wells (Number of Elements) Tennessee Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

335

Pennsylvania Natural Gas Number of Gas and Gas Condensate Wells...  

Gasoline and Diesel Fuel Update (EIA)

Gas and Gas Condensate Wells (Number of Elements) Pennsylvania Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4...

336

Arkansas Natural Gas Number of Gas and Gas Condensate Wells ...  

Annual Energy Outlook 2012 (EIA)

Gas and Gas Condensate Wells (Number of Elements) Arkansas Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

337

Maryland Natural Gas Number of Gas and Gas Condensate Wells ...  

Gasoline and Diesel Fuel Update (EIA)

Gas and Gas Condensate Wells (Number of Elements) Maryland Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

338

Illinois Natural Gas Number of Gas and Gas Condensate Wells ...  

U.S. Energy Information Administration (EIA) Indexed Site

Gas and Gas Condensate Wells (Number of Elements) Illinois Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

339

Missouri Natural Gas Number of Gas and Gas Condensate Wells ...  

Gasoline and Diesel Fuel Update (EIA)

Gas and Gas Condensate Wells (Number of Elements) Missouri Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

340

Mississippi Natural Gas Number of Gas and Gas Condensate Wells...  

U.S. Energy Information Administration (EIA) Indexed Site

Gas and Gas Condensate Wells (Number of Elements) Mississippi Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4...

Note: This page contains sample records for the topic "dust particles gas" 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

Nebraska Natural Gas Number of Gas and Gas Condensate Wells ...  

Annual Energy Outlook 2012 (EIA)

Gas and Gas Condensate Wells (Number of Elements) Nebraska Natural Gas Number of Gas and Gas Condensate Wells (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

342

Experimental Study on the Influence of Initial Pressure on Explosion of Methane-coal Dust Mixtures  

Science Journals Connector (OSTI)

Abstract Methane-coal dust explosion belongs to chemical explosion which always directly causes fire disasters. When it comes to coal mine, the gas explosion easily leads to extensive burning and forms large area stereo fire finally, due to the big blast power and many combustible materials at the scene of an accident. In order to study the explosion characteristics of methane-coal dust mixture explosion as well as to reveal the effects of initial pressure on the explosion, a rectangular explosion test vessel which is 60 cm long and with 10 cm × 10 cm cross-section was used. Different initial pressures, such as 0.2 MPa, 0.25 MPa, 0.3 MPa and 0.35 MPa were considered in this paper. The explosion pressure was measured with PCB pressure transducers, and the maximum rate of explosion pressure rise was determined based on these measured data. The results show that the maximum explosion overpressure and maximum rate of overpressure rise increase with the increasing of the initial pressures and coal dust concentration.

Yuan Li; Hongli Xu; Xishi Wang

2013-01-01T23:59:59.000Z

343

The heating mechanism for the warm/cool dust in powerful, radio-loud AGN  

E-Print Network (OSTI)

The uncertainty surrounding the nature of the heating mechanism for the dust that emits at mid- to far-IR (MFIR) wavelengths in active galaxies limits our understanding of the links between active galactic nuclei (AGN) and galaxy evolution, as well as our ability to interpret the prodigious infrared and sub-mm emission of some of the most distant galaxies in the Universe. Here we report deep Spitzer observations of a complete sample of powerful, intermediate redshift (0.05 power, as traced by [OIII]5007 emission, is strongly correlated with both the mid-IR (24 micron) and the far-IR (70 micron) luminosities, however, with increased scatter in the 70 micron correlation. A major cause of this increased scatter is a group of objects that falls above the main correlation and displays evidence for prodigious recent star formation activity at optical wavelengths, along with relatively cool MFIR colours. These results provide evidence that illumination by the AGN is the primary heating mechanism for the dust emitting at both 24 and 70 microns, with starbursts dominating the heating of the cool dust in only 20 -- 30% of objects. This implies that powerful AGN are not always accompanied by the type of luminous starbursts that are characteristic of the peak of activity in major gas-rich mergers.

C. Tadhunter; D. Dicken; J. Holt; K. Inskip; R. Morganti; D. Axon; C. Buchanan; R. González Delgado; P. Barthel; I. van Bemmel

2007-03-30T23:59:59.000Z

344

KINETIC CONDENSATION AND EVAPORATION OF METALLIC IRON AND IMPLICATIONS FOR METALLIC IRON DUST FORMATION  

SciTech Connect

Metallic iron is one of the most abundant condensing materials in systems of solar abundance. Because metallic iron is responsible for the continuum opacity of dust particles, it has a large contribution to the thermal structure of circumstellar environments and hence to dust evolution itself. In order to understand the formation processes of metallic iron in circumstellar environments, condensation and evaporation kinetics of metallic iron were studied experimentally. Metallic iron condenses at the maximum rate with the condensation coefficient (a parameter ranging from 0 to 1 to represent kinetic hindrance for surface reaction) of unity under high supersaturation conditions, and evaporates nearly ideally (evaporation coefficient of unity) in vacuum. On the other hand, evaporation of metallic iron takes place with more kinetic hindrance in the presence of metallic iron vapor. It is also found that metallic iron atoms nucleate heterogeneously on Al{sub 2}O{sub 3}. Metallic iron does not necessarily condense homogeneously in circumstellar environments, but might condense through heterogeneous nucleation on pre-existing dust. Metallic iron formation proceeds with little kinetic hindrance for highly unequilibrated conditions, but the effects of kinetic hindrance may appear for evaporation and condensation occurring near equilibrium with a timescale of months to years in protoplanetary disks.

Tachibana, Shogo; Nagahara, Hiroko; Ozawa, Kazuhito; Ikeda, Youhei; Nomura, Ryuichi; Tatsumi, Keisuke; Joh, Yui, E-mail: tachi@eps.s.u-tokyo.ac.jp [Department of Earth and Planetary Science, University of Tokyo, 7-3-1 Hongo, Tokyo 113-0033 (Japan)

2011-07-20T23:59:59.000Z

345

Aerosol Impacts on California Winter Clouds and Precipitation during CalWater 2011: Local Pollution versus Long-Range Transported Dust  

SciTech Connect

Mineral dust aerosols often observed over California in winter and spring, associated with long-range transport from Asia and Sahara, have been linked to enhanced precipitation based on observations. Local anthropogenic pollution, on the other hand, was shown in previous observational and modeling studies to reduce precipitation. Here we incorporate recent developments in ice nucleation parameterizations to link aerosols with ice crystal formation in a spectral-bin cloud microphysical model coupled with the Weather Research and Forecasting (WRF) model, to examine the relative and combined impacts of dust and local pollution particles on cloud properties and precipitation type and intensity. Simulations are carried out for two cloud cases with contrasting meteorology and cloud dynamics that occurred on February 16 (FEB16) and March 02 (MAR02) from the CalWater 2011 field campaign. In both cases, observations show the presence of dust and biological particles in a relative pristine environment. The simulated cloud microphysical properties and precipitation show reasonable agreement with aircraft and surface measurements. Model sensitivity experiments indicate that in the pristine environment, the dust and biological aerosol layers increase the accumulated precipitation by 10-20% from the Central Valley to the Sierra Nevada Mountains for both FEB16 and MAR02 due to a ~40% increase in snow formation, validating the observational hypothesis. Model results show that local pollution increases precipitation over the windward slope of the mountains by few percent due to increased snow formation when dust is present but reduces precipitation by 5-8% if dust is removed on FEB16. The effects of local pollution on cloud microphysics and precipitation strongly depend on meteorology including the strength of the Sierra Barrier Jet, and cloud dynamics. This study further underscores the importance of the interactions between local pollution, dust, and environmental conditions for assessing aerosol effects on cold season precipitation in California.

Fan, Jiwen; Leung, Lai-Yung R.; DeMott, Paul J.; Comstock, Jennifer M.; Singh, Balwinder; Rosenfeld, Daniel; Tomlinson, Jason M.; White, Allen B.; Prather, Kimberly; Minnis, Patrick; Ayers, J. K.; Min, Qilong

2014-01-03T23:59:59.000Z

346

Dust-induced instability in a rotating plasma  

SciTech Connect

The effect of immobile dust on stability of a magnetized rotating plasma is analyzed. In the presence of dust, a term containing an electric field appears in the one-fluid equation of plasma motion. This electric field leads to an instability of the magnetized rotating plasma called the dust-induced rotational instability (DRI). The DRI is related to the charge imbalance between plasma ions and electrons introduced by the presence of charged dust. In contrast to the well-known magnetorotational instability requiring the decreasing radial profile of the plasma rotation frequency, the DRI can appear for an increasing rotation frequency profile.

Mikhailovskii, A. B.; Vladimirov, S. V.; Lominadze, J. G.; Tsypin, V. S.; Churikov, A. P.; Erokhin, N. N.; Galvao, R. M. O. [Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, 1, Kurchatov Sq., Moscow 123182 (Russian Federation); School of Physics, University of Sydney, Sydney, N.S.W. 2006 (Australia); Kharadze Abastumani National Astrophysical Observatory, 2a, Kazbegi Ave., Tbilisi 0160 (Georgia); Brazilian Center for Physics Research, Rua Xavier Sigaud, 150, 22290-180, Rio de Janeiro (Brazil); Syzran Branch of Samara Technical University, 45, Sovetskaya Str., Syzran, Samara Region 446001 (Russian Federation); Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, 1, Kurchatov Sq., Moscow 123182 (Russian Federation); Physics Institute, University of Sao Paulo, Cidade Universitaria, 05508-900, Sao Paulo, Brazil and Brazilian Center for Physics Research, Rua Xavier Sigaud, 150, 22290-180, Rio de Janeiro (Brazil)

2008-01-15T23:59:59.000Z

347

Space Dust Analysis Could Provide Clues to Solar System Origins  

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

of oxygen. Isotope analysis could help confirm that the dust originated outside the solar system, but it's a process that would destroy the precious samples. For now,...

348

Dust and Chemical Abundances of the Sagittarius Dwarf Galaxy Planetary Nebula Hen2-436  

Science Journals Connector (OSTI)

We have estimated elemental abundances of the planetary nebula (PN) Hen2-436 in the Sagittarius (Sgr) spheroidal dwarf galaxy using ESO/VLT FORS2, Magellan/MMIRS, and Spitzer/IRS spectra. We have detected candidates of fluorine [F II] ?4790, krypton [Kr III] ?6826, and phosphorus [P II] ?7875 lines and successfully estimated the abundances of these elements ([F/H] = +1.23, [Kr/H] = +0.26, [P/H] = +0.26) for the first time. These elements are known to be synthesized by the neutron capture process in the He-rich intershell during the thermally pulsing asymptotic giant branch (AGB) phase. We present a relation between C, F, P, and Kr abundances among PNe and C-rich stars. The detections of these elements in Hen2-436 support the idea that F, P, Kr together with C are synthesized in the same layer and brought to the surface by the third dredge-up. We have detected N II and O II optical recombination lines (ORLs) and derived the N2+ and O2+ abundances. The discrepancy between the abundance derived from the oxygen ORL and that derived from the collisionally excited line is >1 dex. To investigate the status of the central star of the PN, nebula condition, and dust properties, we construct a theoretical spectral energy distribution (SED) model to match the observed SED with CLOUDY. By comparing the derived luminosity and temperature of the central star with theoretical evolutionary tracks, we conclude that the initial mass of the progenitor is likely to be ~1.5-2.0 M ? and the age is ~3000 yr after the AGB phase. The observed elemental abundances of Hen2-436 can be explained by a theoretical nucleosynthesis model with a star of initial mass 2.25 M ?, Z = 0.008, and LMC compositions. We have estimated the dust mass to be 2.9?10–4 M ? (amorphous carbon only) or 4.0?10–4 M ? (amorphous carbon and polycyclic aromatic hydrocarbon). Based on the assumption that most of the observed dust is formed during the last two thermal pulses and the dust-to-gas mass ratio is 5.58 ? 10–3, the dust mass-loss rate and the total mass-loss rate are –8 M ? yr–1and –6 M ? yr–1, respectively. Our estimated dust mass-loss rate is comparable to a Sgr dwarf galaxy AGB star with similar metallicity and luminosity.

Masaaki Otsuka; Margaret Meixner; David Riebel; Siek Hyung; Akito Tajitsu; Hideyuki Izumiura

2011-01-01T23:59:59.000Z

349

CURVED WALLS: GRAIN GROWTH, SETTLING, AND COMPOSITION PATTERNS IN T TAURI DISK DUST SUBLIMATION FRONTS  

SciTech Connect

The dust sublimation walls of disks around T Tauri stars represent a directly observable cross-section through the disk atmosphere and midplane. Their emission properties can probe the grain size distribution and composition of the innermost regions of the disk, where terrestrial planets form. Here we calculate the inner dust sublimation wall properties for four classical T Tauri stars with a narrow range of spectral types and inclination angles and a wide range of mass accretion rates to determine the extent to which the walls are radially curved. Best fits to the near- and mid-IR excesses are found for curved, two-layer walls in which the lower layer contains larger, hotter, amorphous pyroxene grains with Mg/(Mg+Fe) = 0.6 and the upper layer contains submicron, cooler, mixed amorphous olivine and forsterite grains. As the mass accretion rates decrease from 10{sup –8} to 10{sup –10} M{sub ?} yr{sup –1}, the maximum grain size in the lower layer decreases from ?3 to 0.5 ?m. We attribute this to a decrease in fragmentation and turbulent support for micron-sized grains with decreasing viscous heating. The atmosphere of these disks is depleted of dust with dust-gas mass ratios 1 × 10{sup –4} of the interstellar medium (ISM) value, while the midplane is enhanced to eight times the ISM value. For all accretion rates, the wall contributes at least half of the flux in the optically thin 10 ?m silicate feature. Finally, we find evidence for an iron gradient in the disk, suggestive of that found in our solar system.

McClure, M. K.; Calvet, N.; Hartmann, L.; Ingleby, L. [Department of Astronomy, The University of Michigan, 500 Church Street, 830 Dennison Building., Ann Arbor, MI 48109 (United States); D'Alessio, P. [Centro de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, 58089 Morelia, Michoacán (Mexico); Espaillat, C. [Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Sargent, B. [Center for Imaging Science and Laboratory for Multiwavelength Astrophysics, Rochester Institute of Technology, 54 Lomb Memorial Drive, Rochester, NY 14623 (United States); Watson, D. M. [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627 (United States); Hernández, J., E-mail: melisma@umich.edu, E-mail: ncalvet@umich.edu, E-mail: lhartm@umich.edu, E-mail: lingleby@umich.edu, E-mail: p.dalessio@astrosmo.unam.mx, E-mail: cespaillat@cfa.harvard.edu, E-mail: baspci@rit.edu, E-mail: dmw@pas.rochester.edu, E-mail: hernandj@cida.ve [Centro de Investigaciones de Astronomía (CIDA), Mérida 5101-A (Venezuela, Bolivarian Republic of)

2013-10-01T23:59:59.000Z

350

Microseismic Tracer Particles for Hydraulic Fracturing  

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

Microseismic Tracer Particles for Hydraulic Fracturing Microseismic Tracer Particles for Hydraulic Fracturing Microseismic Tracer Particles for Hydraulic Fracturing Scientists at Los Alamos National Laboratory have developed a method by which microseismic events can be discriminated/detected that correspond to only the portion of the hydraulic fracture that contains the proppant material and can be expected to be conductive to the flow of oil and gas. July 3, 2013 Microseismic Tracer Particles for Hydraulic Fracturing Figure 1: A graph of ionic conductivity as a function of temperature for the anti-perovskite Li3OCl. Available for thumbnail of Feynman Center (505) 665-9090 Email Microseismic Tracer Particles for Hydraulic Fracturing Applications: Oil and gas production Geophysical exploration Benefits: Tracks the disposition of material in a hydraulic fracturing

351

PROBING INTERSTELLAR DUST WITH INFRARED ECHOES FROM THE Cas A SUPERNOVA  

SciTech Connect

We present the analysis of an Infrared Spectrograph 5-38 {mu}m spectrum and Multiband Imaging Photometer for Spitzer photometric measurements of an infrared echo near the Cassiopeia A (Cas A) supernova (SN) remnant observed with the Spitzer Space Telescope. We have modeled the recorded echo accounting for polycyclic aromatic hydrocarbons (PAHs), quantum-heated carbon and silicate grains, as well as thermal carbon and silicate particles. Using the fact that optical light-echo spectroscopy has established that Cas A originated from a Type IIb SN explosion showing an optical spectrum remarkably similar to the prototypical Type IIb SN 1993J, we use the latter to construct template data input for our simulations. We are then able to reproduce the recorded infrared echo spectrum by combining the emission of dust heated by the UV burst produced at the shock breakout after the core-collapse and dust heated by optical light emitted near the visual maximum of the SN light curve, where the UV burst and optical light curve characteristics are based on SN 1993J. We find a mean density of {approx}680 H cm{sup -3} for the echo region, with a size of a few light years across. We also find evidence of dust processing in the form of a lack of small PAHs with less than {approx}300 carbon atoms, consistent with a scenario of PAHs destruction by the UV burst via photodissociation at the estimated distance of the echo region from Cas A. Furthermore, our simulations suggest that the weak 11 {mu}m features of our recorded infrared echo spectrum are consistent with a strong dehydrogenated state of the PAHs. This exploratory study highlights the potential of investigating dust processing in the interstellar medium through infrared echoes.

Vogt, Frederic P. A. [Mount Stromlo Observatory, Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston Creek, ACT 2611 (Australia); Besel, Marc-Andre; Krause, Oliver; Dullemond, Cornelis P., E-mail: fvogt@mso.anu.edu.au [Max-Planck Institut fuer Astronomie, Koenigstuhl 17, 69117 Heidelberg (Germany)

2012-05-10T23:59:59.000Z

352

High-Latitude Dust Over the North Atlantic: Inputs from Icelandic Proglacial Dust Storms  

Science Journals Connector (OSTI)

...agustsson H. Olafsson H. , Forecasting wind gusts in complex terrain . Meteorol. Atmos...composition of African dust measured in trade wind aerosols at Barbados and Miami...version of this article illus. incl. sketch maps United States 201225 10.1126/science...

Joseph M. Prospero; Joanna E. Bullard; Richard Hodgkins

2012-03-02T23:59:59.000Z

353

Evaluation of the modified Anderson sampler for determining particle size distributions and respirable concentrations of particulate matter present in the working environment of cottonseed oil mills  

E-Print Network (OSTI)

to fluctuate during the day within the same work areas. From the particle size data, it was evident that, to fully characterize the dust collected, addi- tional stages were required. At least two additional stages, one with a 40 um effective cutoff diameter..., would have provided a more complete dust characterization. Also, it was evident that a high percentage of the particulate matter was in the 7 to 100 um in diameter particle size range. Unusually high concentrations of dust in this range were found...

Matlock, Stanley Wayne

2012-06-07T23:59:59.000Z

354

Effects of dust size distribution on dust negative ion acoustic solitary waves in a magnetized dusty plasma  

SciTech Connect

Dust negative ion acoustic solitary waves in a magnetized multi-ion dusty plasma containing hot isothermal electron, ions (light positive ions and heavy negative ions) and extremely massive charge fluctuating dust grains are investigated by employing the reductive perturbation method. How the dust size distribution affect the height and the thickness of the nonlinear solitary wave are given. It is noted that the characteristic of the solitary waves are different with the different dust size distribution. The magnitude of the external magnetic field also affects the solitary wave form.

Ma, Yi-Rong; Qi, Xin; Sun, Jian-An; Duan, Wen-Shan [Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China and College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China)] [Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China and College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Yang, Lei [Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China and College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China) [Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China and College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Department of Physics, Lanzhou University, Lanzhou 730000 (China)

2013-08-15T23:59:59.000Z

355

Atmospheric Aerosols Aging Involving Organic Compounds and Impacts on Particle Properties  

E-Print Network (OSTI)

) and chemical reactions (oxidation of particles by gas-phase oxidants and heterogeneous reactions between gas molecules and particles).5 For example, when initially formed, soot particles are hydrophobic and fractal in morphology, with low effective density... particles have a ? value of 1.0; whereas fractal ones will have ? > 1.0. Measurements of Aerosol Optical Properties The optical system consisted of a commercial integrating Nephelometer (Model 3563, TSI) and a CRDS connected in series.20 The particles...

Qiu, Chong

2013-02-01T23:59:59.000Z

356

E-Print Network 3.0 - african mineral dust Sample Search Results  

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

mineral dust Page: << < 1 2 3 4 5 > >> 1 Sensitivity of regional dust modelling to the wind speed and the emissions schemes: Impact on the hourly dust previsibility Summary:...

357

Morphology hypothesized to influence aerosol particle deliquescencew A. L. Mifflin, M. L. Smith and S. T. Martin*  

E-Print Network (OSTI)

of the particle bearing aqueous solution is equal to that of the solid particle surrounded by gas-phase water, however, such as particle coatings that slow gas-particle water exchange, can inhibit deliquescence, shifting the limiting process from a thermo- dynamic threshold to a kinetic limitation on the mass transfer

358

The application scope of the reductive perturbation method and the upper limit of the dust acoustic solitary waves in a dusty plasma  

SciTech Connect

The dust acoustic solitary waves have been numerically investigated by using one dimensional electrostatic particle-in-cell method. By comparing the numerical results with those obtained from the traditional reductive perturbation method, it is found that there exist the maximum dimensionless amplitude and propagation speed of the dust acoustic solitary wave. And these limitations of the solitary wave are explained by using the Sagdeev potential technique. Furthermore, it is noticed that although ? ? 1 is required in the reductive perturbation method generally, the reductive perturbation method is also valid for ??

Qi, Xin; Xu, Yan-xia; Duan, Wen-shan, E-mail: duanws@nwnu.edu.cn [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China and Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou, 730070 Gansu (China)] [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China and Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou, 730070 Gansu (China); Yang, Lei, E-mail: lyang@impcas.ac.cn [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China and Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou, 730070 Gansu (China) [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China and Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou, 730070 Gansu (China); Department of Physics, Lanzhou University, Lanzhou 730000 (China)

2014-01-15T23:59:59.000Z

359

Dust production from sub-solar to super-solar metallicity in Thermally Pulsing Asymptotic Giant Branch Stars  

E-Print Network (OSTI)

We discuss the dust chemistry and growth in the circumstellar envelopes (CSEs) of Thermally Pulsing Asymptotic Giant Branch (TP-AGB) star models computed with the COLIBRI code, at varying initial mass and metallicity (Z=0.001, 0.008, 0.02, 0.04, 0.06). A relevant result of our analysis deals with the silicate production in M-stars. We show that, in order to reproduce the observed trend between terminal velocities and mass-loss rates in Galactic M-giants, one has to significantly reduce the efficiency of chemisputtering by H2 molecules, usually considered as the most effective dust destruction mechanism. This indication is also in agreement with the most recent laboratory results, which show that silicates may condense already at T=1400 K, instead than at Tcond=1000 K, as obtained by models that include chemisputtering. From the analysis of the total dust ejecta, we find that the total dust-to-gas ejecta of intermediate-mass stars are much less dependent on metallicity than usually assumed. In a broader contex...

Ambra, Nanni; Paola, Marigo; Léo, Girardi; Atefeh, Javadi; Jacco, van Loon

2014-01-01T23:59:59.000Z

360

Investigation of metal dusting mechanism in Fe-base alloys using Raman spectroscopy, x-ray diffraction, and electron microscopy.  

SciTech Connect

The metal-dusting phenomenon, which is a metal loss process that occurs in hot reactive gases, was investigated in iron and certain iron-base alloys by Raman scattering, X-ray diffraction (XRD), and scanning-electron microscopy (SEM). Coke from metal dusting exhibits six Raman bands at 1330(D band), 1580(G band), 1617, 2685, 3920, and 3235 cm-1. The bandwidths and the relative intensities of the 1330 and 1580 cm-1 bands are related to the crystallinity and defect structure of the coke. Both Raman and XRD analyses suggest that the metal-dusting process influences the catalytic crystallization of carbon. A new mechanism of metal dusting is, therefore, proposed, based on the premise that coke cannot crystallize well by deposition from carburizing gases at low temperature without catalytic activation because of its strong C-C bonds and high melting temperature. Cementite or iron participates in the coke-crystallizing process in a manner that tends to improve the crystallinity of the coke. At the same time, fine iron or cementite particles are liberated from the pure metal or alloys.

Zeng, Z.; Natesan, K.; Maroni, V. A.

2002-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Managing Nuisance Odor and Dust from Poultry Growing Operations  

E-Print Network (OSTI)

The odor and dust from poultry growing operations can be a nuisance to neighbors. The tips for managing odor and dust contained in this leaflet cover the disposal of dead birds, maintenance of the ventilation system, composting and storing of litter...

Mukhtar, Saqib; Lacey, Ron; Carey, John B.

2001-08-08T23:59:59.000Z

362

APS/123-QED Dust Successive Generations in Complex Plasmas  

E-Print Network (OSTI)

distribution at the entrance of the plasma zone. It is connected to a 13.56 MHz rf gener- ator throughAPS/123-QED Dust Successive Generations in Complex Plasmas: A Cyclic Phenomenon in the Void Region´eans cedex 2, France (Dated: December 5, 2007) Dust formation and growth in plasmas are in most cases

Boyer, Edmond

363

Constraining oceanic dust deposition using surface ocean dissolved Al  

E-Print Network (OSTI)

Constraining oceanic dust deposition using surface ocean dissolved Al Qin Han,1 J. Keith Moore,1; accepted 7 December 2007; published 12 April 2008. [1] We use measurements of ocean surface dissolved Al (DEAD) model to constrain dust deposition to the oceans. Our Al database contains all available

Zender, Charles

364

Online Supplement S1.0 Dust/Climate Interactions  

E-Print Network (OSTI)

by changing the energy balance of solar and thermal radiation [IPCC, 2001]. Dust scatters and also partly absorbs incoming solar radiation, and it also absorbs and re-emits outgoing longwave radiation. Any as the possibility of intensification of easterly waves in North Africa from dust [Jones, et al., 2004]. On the other

Mahowald, Natalie

365

Fermilab | Science | Particle Accelerators  

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

Particle Accelerators Main Injector As America's particle physics laboratory, Fermilab operates and builds powerful particle accelerators for investigating the smallest things...

366

E-Print Network 3.0 - african dust measured Sample Search Results  

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

Sciences and Ecology ; Geosciences 3 Sensitivity of regional dust modelling to the wind speed and the emissions schemes: Impact on the hourly dust previsibility Summary: with...

367

E-Print Network 3.0 - airborne house dust Sample Search Results  

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

of regional dust modelling to the wind speed and the emissions schemes: Impact... on the hourly dust previsibility Laurent MENUT (1), Cyril MOULIN (2), Isabelle CHIAPELLO (3)...

368

Grain quality impacts of prohibiting recombination recirculation dust at export grain elevators  

E-Print Network (OSTI)

. . . 58 Figure A9 ? PSD OF BIN CORN DUST FROM ELEVATOR 7. Figure A10 - PSD OF R/R CORN DUST FROM ELEVATOR 7. Figure A11 - PSD OF INBOUND WHEAT FOR ELEVATOR 5. Figure A12 ? PSD OF OUTBOUND WHEAT FOR ELEVATOR 5. . . . Figure A13 - PSD OF MIXED BIN DUST... the mesh. TABLE 3, MASS FRACTION OF CORN DUSTS LESS THAN 100 MICRONS DETERMINED BY WET SIEVING. Sample % less than 100 mierons Elev 3 R/R Dust Elev 4 Bin Dust Elev 7 Bin Dust Elev 7 R/R Dust 61. 215. 4 32. 3 E 1. 5 59. 0+1. 4 90. 6 10. 9 22...

Spillmann, Daryl Drew

2012-06-07T23:59:59.000Z

369

Molecular gas in nearby powerful radio galaxies  

E-Print Network (OSTI)

We report the detection of CO(1-0) and CO(2-1) emission from the central region of nearby 3CR radio galaxies (z$gas content is below 10$^9$ \\msun. Their individual CO emission exhibit, for 5 cases, a double-horned line profile that is characteristic of an inclined rotating disk with a central depression at the rising part of its rotation curve. The inferred disk or ring distributions of the molecular gas is consistent with the observed presence of dust disks or rings detected optically in the cores of the galaxies. We reason that if their gas originates from the mergers of two gas-rich disk galaxies, as has been invoked to explain the molecular gas in other radio galaxies, then these galaxies must have merged a long time ago (few Gyr or more) but their remnant elliptical galaxies only recently (last 10$^7$ years or less) become active radio galaxies. Instead, we argue the the cannibalism of gas-rich galaxies provide a simpler explanation for the origin of molecular gas in the elliptical hosts of radio galaxies (Lim et al. 2000). Given the transient nature of their observed disturbances, these galaxies probably become active in radio soon after the accretion event when sufficient molecular gas agglomerates in their nuclei.

S. Leon; J. Lim; F. Combes; D. Van-Trung

2001-07-26T23:59:59.000Z

370

Fermilab | Science | Particle Physics | Benefits of Particle...  

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

Benefits of Particle Physics photo Each generation of particle accelerators and detectors builds on the previous one, raising the potential for discovery and pushing the level of...

371

The ecology of dust: local- to global-scale perspectives  

SciTech Connect

Emission and redistribution of dust due to wind erosion in drylands drives major biogeochemical dynamics and provides important aeolian environmental connectivity at scales from individual plants up to the global scale. Yet, perhaps because most relevant research on aeolian processes has been presented in a geosciences rather than ecological context, most ecological studies do not explicitly consider dust-driven processes. To bridge this disciplinary gap, we provide a general overview of the ecological importance of dust, examine complex interactions between wind erosion and ecosystem dynamics from the plant-interspace scale to regional and global scales, and highlight specific examples of how disturbance affects these interactions and their consequences. Changes in climate and intensification of land use will both likely lead to increased dust production. To address these challenges, environmental scientists, land managers and policy makers need to more explicitly consider dust in resource management decisions.

Whicker, Jeffrey J [Los Alamos National Laboratory; Field, Jason P [UA; Belnap, Jayne [NON LANL; Breshears, David D [UA; Neff, Jason [CU; Okin, Gregory S [UCLA; Painter, Thomas H [UNIV OF ARIZONA; Ravi, Sujith [UNIV OF ARIZONA; Reheis, Marith C [UCLA; Reynolds, Richard L [NON LANL

2009-01-01T23:59:59.000Z

372

Sheath formation under collisional conditions in presence of dust  

SciTech Connect

Sheath formation is studied for collisional plasma in presence of dust. In common laboratory plasma, the dust acquires negative charges because of high thermal velocity of the electrons. The usual dust charging theory dealing with the issue is that of the Orbit Motion Limited theory. However, the theory does not find its application when the ion neutral collisions are significantly present. An alternate theory exists in literature for collisional dust charging. Collision is modeled by constant mean free path model. The sheath is considered jointly with the bulk of the plasma and a smooth transition of the plasma profiles from the bulk to the sheath is obtained. The various plasma profiles such as the electrostatic force on the grain, the ion drag force along with the dust density, and velocity are shown to vary spatially with increasing ion neutral collision.

Moulick, R., E-mail: rakesh.moulick@gmail.com; Goswami, K. S. [Centre of Plasma Physics-Institute for Plasma Research, Sonapur-782402, Guwahati (India)

2014-08-15T23:59:59.000Z

373

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

,366 ,366 95,493 1.08 0 0.00 1 0.03 29,406 0.56 1,206 0.04 20,328 0.64 146,434 0.73 - Natural Gas 1996 Million Percent of Million Percent of Cu. Feet National Total Cu. Feet National Total Net Interstate Movements: Industrial: Marketed Production: Vehicle Fuel: Deliveries to Consumers: Electric Residential: Utilities: Commercial: Total: South Carolina South Carolina 88. Summary Statistics for Natural Gas South Carolina, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 0 0 0 0 0 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ...........................................

374

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

0,216 0,216 50,022 0.56 135 0.00 49 1.67 85,533 1.63 8,455 0.31 45,842 1.45 189,901 0.95 - Natural Gas 1996 Million Percent of Million Percent of Cu. Feet National Total Cu. Feet National Total Net Interstate Movements: Industrial: Marketed Production: Vehicle Fuel: Deliveries to Consumers: Electric Residential: Utilities: Commercial: Total: M a r y l a n d Maryland 68. Summary Statistics for Natural Gas Maryland, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... NA NA NA NA NA Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 9 7 7 7 8 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 33 28 26 22 135 From Oil Wells ...........................................

375

Gas distributor for fluidized bed coal gasifier  

DOE Patents (OSTI)

A gas distributor for distributing high temperature reaction gases to a fluidized bed of coal particles in a coal gasification process. The distributor includes a pipe with a refractory reinforced lining and a plurality of openings in the lining through which gas is fed into the bed. These feed openings have an expanding tapered shape in the downstream or exhaust direction which aids in reducing the velocity of the gas jets as they enter the bed.

Worley, Arthur C. (Mt. Tabor, NJ); Zboray, James A. (Irvine, CA)

1980-01-01T23:59:59.000Z

376

On the dry deposition of submicron particles  

SciTech Connect

The air-surface exchange of particles can have a strong role in determining the amount, size, and chemical composition of particles in the troposphere. Here the authors consider only dry processes (deposition processes not directly aided by precipitation) and mostly address particles less than about 2 {micro}m in diameter (often referred to as submicron particles because most of such particles are less than 1 {micro}m in diameter). The processes that control the dry exchange of particulate material between the atmosphere and the surface of the Earth are numerous, highly varied, and sometimes poorly understood. As a result, determining which of the surface processes to parameterize or simulate in modeling the tropospheric mass budget of a particulate substance can be a significant challenge. Dry deposition, for example, can be controlled by a combination of Brownian diffusion, impaction, interception, and gravitational settling, depending on the size of the particles, the roughness of the surface on both micrometeorological and microscopic scales, the geometrical structure of vegetative canopies, and other surface characteristics such as wetness. Particles can be added to the lower atmosphere by resuspension from land surfaces and sea spray. The roles of rapid gas-to-particle conversion and growth or shrinkage of particles as a result of water condensation or evaporation in the lower few meters of the atmosphere can also have a significant impact on particle concentrations in the lower atmosphere. Here, a few micrometeorological observations and inferences on particle air-surface exchange are briefly addressed.

Wesely, M. L.

1999-10-08T23:59:59.000Z

377

Fine Particle Emissions from Combustion Systems  

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

Fine Particle Emissions from Combustion Systems Fine Particle Emissions from Combustion Systems Speaker(s): Allen Robinson Date: November 11, 2005 - 12:00pm Location: 90-3122 Combustion systems such as motor vehicles and power plants are major sources of fine particulate matter. This talk describes some of the changes in fine particle emissions that occur as exhaust from combustion systems mix with background air. This mixing cools and dilutes the exhaust which influences gas-particle partitioning of semi-volatile species, the aerosol size distribution, and the fine particle mass. Dilution sampling is used to characterize fine particle emissions from combustion systems because it simulates the rapid cooling and dilution that occur as exhaust mixes with the atmosphere. Results from dilution sampler

378

,"Missouri Natural Gas Summary"  

U.S. Energy Information Administration (EIA) Indexed Site

Gas Wells (MMcf)","Missouri Natural Gas Gross Withdrawals from Oil Wells (MMcf)","Missouri Natural Gas Gross Withdrawals from Shale Gas (Million Cubic Feet)","Missouri Natural...

379

Chemoresistive gas sensor  

DOE Patents (OSTI)

A chemoresistive gas sensor is provided which has improved sensitivity. A layer of organic semiconductor is disposed between two electrodes which, in turn, are connected to a voltage source. High conductivity material is dispersed within the layer of organic semiconductor in the form of very small particles, or islands. The average interisland spacing is selected so that the predominant mode of current flow is by way of electron funneling. Adsorption of gaseous contaminant onto the layer of organic semiconductor modulates the tunneling current in a quantitative manner. 2 figs.

Hirschfeld, T.B.

1987-06-23T23:59:59.000Z

380

A cosmic abundance standard: chemical homogeneity of the solar neighbourhood and the ISM dust-phase composition  

E-Print Network (OSTI)

A representative sample of unevolved early B-type stars in nearby OB associations and the field is analysed to unprecedented precision using NLTE techniques. The resulting chemical composition is found to be more metal-rich and much more homogeneous than indicated by previous work. A rms scatter of ~10% in abundances is found for the six stars (and confirmed by six evolved stars), the same as reported for ISM gas-phase abundances. A cosmic abundance standard for the present-day solar neighbourhood is proposed, implying mass fractions for hydrogen, helium and metals of X=0.715, Y=0.271 and Z=0.014. Good agreement with solar photospheric abundances as reported from recent 3D radiative-hydrodynamical simulations of the solar atmosphere is obtained. As a first application we use the cosmic abundance standard as a proxy for the determination of the local ISM dust-phase composition, putting tight observational constraints on dust models.

Norbert Przybilla; Maria-Fernanda Nieva; Keith Butler

2008-09-14T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

68,747 68,747 34,577 0.39 0 0.00 34 1.16 14,941 0.29 0 0.00 11,506 0.36 61,058 0.31 I d a h o Idaho 60. Summary Statistics for Natural Gas Idaho, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 0 0 0 0 0 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 0 0 0 0 0 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ............... 0 0 0 0 0 Wet After Lease Separation.......................... 0 0 0 0 0 Vented

382

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

0 0 0 0.00 0 0.00 0 0.00 540 0.01 0 0.00 2,132 0.07 2,672 0.01 H a w a i i Hawaii 59. Summary Statistics for Natural Gas Hawaii, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 0 0 0 0 0 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 0 0 0 0 0 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ............... 0 0 0 0 0 Wet After Lease Separation.......................... 0 0 0 0 0 Vented and Flared

383

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

483,052 483,052 136,722 1.54 6,006 0.03 88 3.00 16,293 0.31 283,557 10.38 41,810 1.32 478,471 2.39 F l o r i d a Florida 57. Summary Statistics for Natural Gas Florida, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 47 50 98 92 96 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ........................................... 7,584 8,011 8,468 7,133 6,706 Total.............................................................. 7,584 8,011 8,468 7,133 6,706 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ...............

384

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

291,898 291,898 113,995 1.29 0 0.00 4 0.14 88,078 1.68 3,491 0.13 54,571 1.73 260,140 1.30 I o w a Iowa 63. Summary Statistics for Natural Gas Iowa, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 0 0 0 0 0 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 0 0 0 0 0 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ............... 0 0 0 0 0 Wet After Lease Separation.......................... 0 0 0

385

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

Vehicle Fuel: Vehicle Fuel: Deliveries to Consumers: Electric Residential: Utilities: Commercial: Total: New England New England 36. Summary Statistics for Natural Gas New England, 1992-1996 Table 691,089 167,354 1.89 0 0.00 40 1.36 187,469 3.58 80,592 2.95 160,761 5.09 596,215 2.98 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 0 0 0 0 0 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 0 0 0 0 0 Repressuring ................................................

386

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

29,693 29,693 0 0.00 0 0.00 6 0.20 17,290 0.33 0 0.00 16,347 0.52 33,644 0.17 District of Columbia District of Columbia 56. Summary Statistics for Natural Gas District of Columbia, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 0 0 0 0 0 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 0 0 0 0 0 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ............... 0 0 0 0 0 Wet After Lease Separation..........................

387

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

42,980 42,980 14,164 0.16 0 0.00 1 0.03 9,791 0.19 23,370 0.86 6,694 0.21 54,020 0.27 D e l a w a r e Delaware 55. Summary Statistics for Natural Gas Delaware, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 0 0 0 0 0 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 0 0 0 0 0 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ............... 0 0 0 0 0 Wet After Lease Separation..........................

388

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

-49,536 -49,536 7,911 0.09 49,674 0.25 15 0.51 12,591 0.24 3 0.00 12,150 0.38 32,670 0.16 North Dakota North Dakota 82. Summary Statistics for Natural Gas North Dakota, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 496 525 507 463 462 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 104 101 104 99 108 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 12,461 18,892 19,592 16,914 16,810 From Oil Wells ........................................... 47,518 46,059 43,640 39,760 38,906 Total.............................................................. 59,979 64,951 63,232 56,674 55,716 Repressuring ................................................

389

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

21,547 21,547 4,916 0.06 0 0.00 0 0.00 7,012 0.13 3 0.00 7,099 0.22 19,031 0.10 N e w H a m p s h i r e New Hampshire 77. Summary Statistics for Natural Gas New Hampshire, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 0 0 0 0 0 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 0 0 0 0 0 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ............... 0 0 0 0 0 Wet After Lease Separation..........................

390

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

139,881 139,881 26,979 0.30 463 0.00 115 3.92 27,709 0.53 19,248 0.70 28,987 0.92 103,037 0.52 A r i z o n a Arizona 50. Summary Statistics for Natural Gas Arizona, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... NA NA NA NA NA Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 6 6 6 7 7 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 721 508 711 470 417 From Oil Wells ........................................... 72 110 48 88 47 Total.............................................................. 794 618 759 558 464 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ............... 0 0 0 0 0 Wet After Lease

391

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

Middle Middle Atlantic Middle Atlantic 37. Summary Statistics for Natural Gas Middle Atlantic, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 1,857 1,981 2,042 1,679 1,928 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 36,906 36,857 26,180 37,159 38,000 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 161,372 152,717 140,444 128,677 152,494 From Oil Wells ........................................... 824 610 539 723 641 Total.............................................................. 162,196 153,327 140,982 129,400 153,134 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed

392

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

386,690 386,690 102,471 1.16 0 0.00 43 1.47 142,319 2.72 5,301 0.19 98,537 3.12 348,671 1.74 M i n n e s o t a Minnesota 71. Summary Statistics for Natural Gas Minnesota, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 0 0 0 0 0 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 0 0 0 0 0 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ............... 0 0 0 0 0 Wet After Lease Separation..........................

393

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

1,108,583 1,108,583 322,275 3.63 298 0.00 32 1.09 538,749 10.28 25,863 0.95 218,054 6.90 1,104,972 5.52 I l l i n o i s Illinois 61. Summary Statistics for Natural Gas Illinois, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... NA NA NA NA NA Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 382 385 390 372 370 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 337 330 323 325 289 From Oil Wells ........................................... 10 10 10 10 9 Total.............................................................. 347 340 333 335 298 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ...............

394

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

286,485 286,485 71,533 0.81 25 0.00 31 1.06 137,225 2.62 5,223 0.19 72,802 2.31 286,814 1.43 M i s s o u r i Missouri 73. Summary Statistics for Natural Gas Missouri, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... NA NA NA NA NA Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 5 8 12 15 24 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 27 14 8 16 25 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 27 14 8 16 25 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ............... 0 0 0 0 0 Wet After Lease Separation..........................

395

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

411,951 411,951 100,015 1.13 0 0.00 5 0.17 114,365 2.18 45,037 1.65 96,187 3.05 355,609 1.78 Massachusetts Massachusetts 69. Summary Statistics for Natural Gas Massachusetts, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 0 0 0 0 0 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 0 0 0 0 0 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ............... 0 0 0 0 0 Wet After Lease Separation..........................

396

Gas vesicles.  

Science Journals Connector (OSTI)

...in the suspending water, of concentration...MPa and balances the atmospheric pressure. Note that...versely, liquid water could not form by condensation inside the gas vesicle...presumably surrounded by water on all sides. At...

A E Walsby

1994-03-01T23:59:59.000Z

397

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

226,798 226,798 104,124 1.17 0 0.00 0 0.00 58,812 1.12 2,381 0.09 40,467 1.28 205,783 1.03 North Carolina North Carolina 81. Summary Statistics for Natural Gas North Carolina, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 0 0 0 0 0 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 0 0 0 0 0 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 0 0 0 0 0 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 0 0 0 0 0 Repressuring ................................................ 0 0 0 0 0 Nonhydrocarbon Gases Removed ............... 0 0 0 0 0 Wet After Lease Separation..........................

398

Gas sensitive materials for gas detection and methods of making  

SciTech Connect

A gas sensitive material comprising SnO.sub.2 nanocrystals doped with In.sub.2O.sub.3 and an oxide of a platinum group metal, and a method of making the same. The platinum group metal is preferably Pd, but also may include Pt, Ru, Ir, and combinations thereof. The SnO.sub.2 nanocrystals have a specific surface of 7 or greater, preferably about 20 m2/g, and a mean particle size of between about 10 nm and about 100 nm, preferably about 40 nm. A gas detection device made from the gas sensitive material deposited on a substrate, the gas sensitive material configured as a part of a current measuring circuit in communication with a heat source.

Trakhtenberg, Leonid Israilevich; Gerasimov, Genrikh Nikolaevich; Gromov, Vladimir Fedorovich; Rozenberg, Valeriya Isaakovna

2014-07-15T23:59:59.000Z

399

Theoretical study of head-on collision of dust acoustic solitary waves in a strongly coupled complex plasma  

SciTech Connect

We investigate the propagation characteristics of two counter propagating dust acoustic solitary waves (DASWs) undergoing a head-on collision, in the presence of strong coupling between micron sized charged dust particles in a complex plasma. A coupled set of nonlinear dynamical equations describing the evolution of the two DASWs using the extended Poincaré-Lighthill-Kuo perturbation technique is derived. The nature and extent of post collision phase-shifts of these solitary waves are studied over a wide range of dusty plasma parameters in a strongly and a weakly coupled medium. We find a significant change in the nature and amount of phase delay in the strongly coupled regime as compared to a weakly coupled regime. The phase shift is seen to change its sign beyond a threshold value of compressibility of the medium for a given set of dusty plasma parameters.

Jaiswal, S., E-mail: surabhi@ipr.res.in; Bandyopadhyay, P.; Sen, A. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

2014-05-15T23:59:59.000Z

400

Particle correlations in a Fermi superfluid  

Science Journals Connector (OSTI)

We discuss the correlations between particles of different momentum in a superfluid Fermi gas, accessible through noise measurements of the absorption images of the expanded gas. We include two elements missing from the simplest treatment, based on the BCS wavefunction: the explicit use of a conserving approximation satisfying particle number conservation and the inclusion of the contribution from Cooper pairs at finite momentum. We expect the latter to be a significant issue in the strongly correlated state emerging in the BCS-Bose-Einstein condensate (BEC) crossover.

A. Lamacraft

2006-01-20T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Method for improved gas-solids separation  

DOE Patents (OSTI)

Methods are disclosed for the removal of particulate solids from a gas stream at high separation efficiency, including the removal of submicron size particles. The apparatus includes a cyclone separator type of device which contains an axially mounted perforated cylindrical hollow rotor. The rotor is rotated at high velocity in the same direction as the flow of an input particle-laden gas stream to thereby cause enhanced separation of particulate matter from the gas stream in the cylindrical annular space between the rotor and the sidewall of the cyclone vessel. Substantially particle-free gas passes through the perforated surface of the spinning rotor and into the hollow rotor, from where it is discharged out of the top of the apparatus. Separated particulates are removed from the bottom of the vessel. 4 figs.

Kusik, C.L.; He, B.X.

1990-11-13T23:59:59.000Z

402

Reducing dust emissions at OAO Alchevskkoks coke battery 10A  

SciTech Connect

Coke battery 10A with rammed batch is under construction at OAO Alchevskkoks. The design documentation developed by Giprokoks includes measures for reducing dust emissions to the atmosphere. Aspiration systems with dry dust trapping are employed in the new components of coke battery 10A and in the existing coke-sorting equipment. Two-stage purification of dusty air in cyclones and bag filters is employed for the coke-sorting equipment. This system considerably reduces coke-dust emissions to the atmosphere.

T.F. Trembach; E.N. Lanina [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

2009-07-15T23:59:59.000Z

403

Simulating Microstructural Evolution and Electrical Transport in Ceramic Gas Sensors  

E-Print Network (OSTI)

. In this paper, using the example of the thermal processing of ceramic gas sensors, an integrated compu- tationalSimulating Microstructural Evolution and Electrical Transport in Ceramic Gas Sensors Yunzhi Wang in ceramic gas sensors has been proposed. First, the particle-flow model and the continuum-phase-field method

Ciobanu, Cristian

404

Neutron microdosimetric response of a gas electron multiplier  

Science Journals Connector (OSTI)

......avalanching structure called the gas electron multiplier...MSGC including its high cost per unit area, the inability...metallic strips, a counting gas region and a cathode...below 10 keV microm1. The production of alpha particles, through...heavy recoil ions in the gas produced the high LET......

J. Dubeau; A. J. Waker

2008-03-01T23:59:59.000Z

405

Nondetection of impulsive radio signals from lightning in Martian dust storms using the radar receiver on  

E-Print Network (OSTI)

emission from a Martian dust storm that they attribute to the excitation of Schumann [1952] resonances

Gurnett, Donald A.

406

Shape-induced gravitational sorting of Saharan dust during transatlantic voyage: Evidence from CALIOP  

E-Print Network (OSTI)

Shape-induced gravitational sorting of Saharan dust during transatlantic voyage: Evidence from of Saharan dust from June to August 2007. Observing along a typical transatlantic dust track, we find that (1 of Saharan dust during transatlantic voyage: Evidence from CALIOP lidar depolarization measurements, Geophys

Kostinski, Alex

407

Rapid Extraction of Dust Impact Tracks from Silica Aerogel by Ultrasonic Micro-blades  

SciTech Connect

In January 2006, NASA's Stardust Mission will return with its valuable cargo of cometary dust particles, the first brought back to Earth, captured at hypervelocity speeds in silica aerogel collectors. Aerogel, a proven capture medium, is also a candidate for future sample return missions and low-earth orbit (LEO) deployments. Critical to the science return of Stardust and future missions using aerogel is the ability to efficiently extract impacted particles from collector tiles. Researchers will be eager to obtain Stardust samples as quickly as possible, and tools for the rapid extraction of particle impact tracks that require little construction, training, or investment would be an attractive asset. To this end, we have experimented with diamond and steel micro-blades. Applying ultrasonic frequency oscillations to these micro-blades via a piezo-driven holder produces rapid, clean cuts in the aerogel with minimal damage to the surrounding collector tile. With this approach, impact tracks in aerogel fragments with low-roughness cut surfaces have been extracted from aerogel tiles flown on NASA's Orbital Debris Collector Experiment. The smooth surfaces produced during cutting reduce imaging artifacts during analysis by SEM. Some tracks have been dissected to expose the main cavity for eventual isolation of individual impact debris particles and further analysis by techniques such as TEM and nanoSIMS.

Ishii, H; Graham, G; Kearsley, A T; Grant, P G; Snead, C J; Bradley, J P

2005-02-17T23:59:59.000Z

408

Dust suppression characteristics of mineral oil when applied to corn, wheat, or soybeans  

E-Print Network (OSTI)

). . . . . . . Percent of Dust Less Than 10 um (PLT10). . Percent of Dust Less Than 16 um (PLT16). . Mass of Dust Less Than 10 pr1 (NLT10). . Mass of Dust Less Than 16 qm (MLT16). . Retention Curves (RC). SUMMARY AND CONCLUSIONS. FUTURE RESEARCH. REFERENCES... OF THEIR RESPECTIVE GRAIN KERNELS. . SUMMARY OF THE MEAN PERCENT OF DUST LESS THAN 10 um (PLT10) VALUES OF CORN, WHEAT, AND SOYBEAN DUSTS ADHERING TO THE SURFACES OF THEIR RESPECTIVE GRAIN KERNELS. SUMMARY OF THE MEAN PERCENT OF DUST LESS THAN 16 um (PLT16...

Jones, David Don

2012-06-07T23:59:59.000Z

409

Air Pollution Control Regulations: No. 5 - Fugitive Dust (Rhode Island) |  

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

5 - Fugitive Dust (Rhode 5 - Fugitive Dust (Rhode Island) Air Pollution Control Regulations: No. 5 - Fugitive Dust (Rhode Island) < Back Eligibility Agricultural Commercial Construction Fed. Government Fuel Distributor General Public/Consumer Industrial Installer/Contractor Institutional Investor-Owned Utility Local Government Low-Income Residential Multi-Family Residential Municipal/Public Utility Nonprofit Residential Retail Supplier Rural Electric Cooperative Schools State/Provincial Govt Systems Integrator Transportation Tribal Government Utility Savings Category Alternative Fuel Vehicles Hydrogen & Fuel Cells Buying & Making Electricity Water Home Weatherization Wind Program Info State Rhode Island Program Type Environmental Regulations Provider Department of Environmental Management These regulations aim to prevent the release of fugitive dust by forbidding

410

Global trends in visibility: implications for dust sources  

E-Print Network (OSTI)

There is a large uncertainty in the relative roles of human land use, climate change and carbon dioxide fertilization in changing desert dust source strength over the past 100 years, and the overall sign of human impacts ...

Mahowald, N. M.; Ballantine, J.A.; Feddema, Johannes J.; Ramankutty, N.

2007-06-01T23:59:59.000Z

411

Pollen analysis of dust preserved in four medieval books  

Science Journals Connector (OSTI)

Pollen spectra of three samples of dust taken from four medieval books are reported. The books, printed A.D. 1500–1530, were preserved in the Franciscan monastery of Kada? (NW Bohemia) up to c. 30 years ago, a...

Vlasta Jankovská

1995-03-01T23:59:59.000Z

412

Ground Gas Handbook  

Science Journals Connector (OSTI)

...pathways of least resistance to gas transport, and applications are discussed, such as migrating landfill gas emissions, also from leaking landfill gas collection systems, as well as natural gas and oil-field gas leakage from abandoned production...

Allen W Hatheway

413

Gas Delivered  

Gasoline and Diesel Fuel Update (EIA)

. Average . Average Price of Natural Gas Delivered to Residential Consumers, 1980-1996 Figure 1980 1982 1984 1986 1988 1990 1992 1994 1996 0 2 4 6 8 10 0 40 80 120 160 200 240 280 320 Dollars per Thousand Cubic Feet Dollars per Thousand Cubic Meters Nominal Dollars Constant Dollars Sources: Nominal dollars: Energy Information Administration (EIA), Form EIA-176, "Annual Report of Natural and Supplemental Gas Supply and Disposition." Constant dollars: Prices were converted to 1995 dollars using the chain-type price indexes for Gross Domestic Product (1992 = 1.0) as published by the U. S. Department of Commerce, Bureau of Economic Analysis. Residential: Prices in this publication for the residential sector cover nearly all of the volumes of gas delivered. Commercial and Industrial: Prices for the commercial and industrial sectors are often associated with

414

Lattice-Boltzmann Simulations of Particle-Fluid Suspensions  

Science Journals Connector (OSTI)

This paper reviews applications of the lattice-Boltzmann method to simulations of particle-fluid suspensions. ... these methods, and then describe results from lattice-gas and lattice-Boltzmann simulations in mor...

A. J. C. Ladd; R. Verberg

2001-09-01T23:59:59.000Z

415

Carbon monoxide-silicon carbide interaction in HTGR fuel particles  

Science Journals Connector (OSTI)

The corrosion of the coating-layers of silicon carbide (SiC) by carbon monoxide (CO) was observed in irradiated Triso-coated uranium dioxide particles, used in high-temperature gas-cooled reactors, by optical ...

Kazuo Minato; Toru Ogawa; Satoru Kashimura; Kousaku Fukuda…

1991-05-01T23:59:59.000Z

416

Neutral particle beam intensity controller  

DOE Patents (OSTI)

A neutral beam intensity controller is provided for a neutral beam generator in which a neutral beam is established by accelerating ions from an ion source into a gas neutralizer. An amplitude modulated, rotating magnetic field is applied to the accelerated ion beam in the gas neutralizer to defocus the resultant neutral beam in a controlled manner to achieve intensity control of the neutral beam along the beam axis at constant beam energy. The rotating magnetic field alters the orbits of ions in the gas neutralizer before they are neutralized, thereby controlling the fraction of neutral particles transmitted out of the neutralizer along the central beam axis to a fusion device or the like. The altered path or defocused neutral particles are sprayed onto an actively cooled beam dump disposed perpendicular to the neutral beam axis and having a central open for passage of the focused beam at the central axis of the beamline. Virtually zero therough 100% intensity control is achieved by varying the magnetic field strength without altering the ion source beam intensity or its species yield.

Dagenhart, William K. (Oak Ridge, TN)

1986-01-01T23:59:59.000Z

417

Statistics of particle time-temperature histories.  

SciTech Connect

Particles in non - isothermal turbulent flow are subject to a stochastic environment tha t produces a distribution of particle time - temperature histories. This distribution is a function of the dispersion of the non - isothermal (continuous) gas phase and the distribution of particles relative to that gas phase. In this work we extend the one - dimensional turbulence (ODT) model to predict the joint dispersion of a dispersed particle phase and a continuous phase. The ODT model predicts the turbulent evolution of continuous scalar fields with a model for the cascade of fluctuations to smaller sc ales (the 'triplet map') at a rate that is a function of the fully resolved one - dimens ional velocity field . Stochastic triplet maps also drive Lagrangian particle dispersion with finite Stokes number s including inertial and eddy trajectory - crossing effect s included. Two distinct approaches to this coupling between triplet maps and particle dispersion are developed and implemented along with a hybrid approach. An 'instantaneous' particle displacement model matches the tracer particle limit and provide s an accurate description of particle dispersion. A 'continuous' particle displacement m odel translates triplet maps into a continuous velocity field to which particles respond. Particles can alter the turbulence, and modifications to the stochastic rate expr ession are developed for two - way coupling between particles and the continuous phase. Each aspect of model development is evaluated in canonical flows (homogeneous turbulence, free - shear flows and wall - bounded flows) for which quality measurements are ava ilable. ODT simulations of non - isothermal flows provide statistics for particle heating. These simulations show the significance of accurately predicting the joint statistics of particle and fluid dispersion . Inhomogeneous turbulence coupled with the in fluence of the mean flow fields on particles of varying properties alter s particle dispersion. The joint particle - temperature dispersion leads to a distribution of temperature histories predicted by the ODT . Predictions are shown for the lower moments an d the full distributions of the particle positions, particle - observed gas temperatures and particle temperatures. An analysis of the time scales affecting particle - temperature interactions covers Lagrangian integral time scales based on temperature autoco rrelations, rates of temperature change associated with particle motion relative to the temperature field and rates of diffusional change of temperatures. These latter two time scales have not been investigated previously; they are shown to be strongly in termittent having peaked distributions with long tails. The logarithm of the absolute value of these time scales exhibits a distribution closer to normal. A cknowledgements This work is supported by the Defense Threat Reduction Agency (DTRA) under their Counter - Weapons of Mass Destruction Basic Research Program in the area of Chemical and Biological Agent Defeat under award number HDTRA1 - 11 - 4503I to Sandia National Laboratories. The authors would like to express their appreciation for the guidance provi ded by Dr. Suhithi Peiris to this project and to the Science to Defeat Weapons of Mass Destruction program.

Hewson, John C.; Lignell, David O.; Sun, Guangyuan

2014-10-01T23:59:59.000Z

418

Remote Gas Well Monitoring Technology Applied to Marcellus Shale Site |  

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

Remote Gas Well Monitoring Technology Applied to Marcellus Shale Remote Gas Well Monitoring Technology Applied to Marcellus Shale Site Remote Gas Well Monitoring Technology Applied to Marcellus Shale Site February 10, 2012 - 12:00pm Addthis Washington, DC - A technology to remotely monitor conditions at energy-rich Marcellus Shale gas wells to help insure compliance with environmental requirements has been developed through a research partnership funded by the U.S. Department of Energy (DOE). NETL-RUA researcher Dr. Michael McCawley hasdeveloped a technology to remotely monitor theenvironment around energy-rich Marcellus Shale gas wells. Photo courtesy of West Virginia University.The technology - which involves three wireless monitoring modules to measure volatile organic compounds, dust, light and sound - is currently being tested at a Marcellus

419

Toward resolution-independent dust emissions in global models: Impacts on the seasonal and spatial distribution of dust  

E-Print Network (OSTI)

Simulating the emission of mineral dust and sea-salt aerosol is nonlinear with surface winds and therefore requires accurate representation of surface winds. Consequently, the resolution of a simulation affects emission ...

Pierce, J. R.

420

Alignment of Dust in Molecular Clouds  

E-Print Network (OSTI)

Polarimetry is one of the most informative techniques of studying magnetic fields in molecular clouds. How reliable the interpretation of the polarization maps in terms of magnetic fields is the issue that the grain alignment theory addresses. We show that grain alignment involves several processes acting simultaneously, but on different time-scales. We explain that rotating dust grains get substantial magnetic moment that allows them precess fast about magnetic field lines. As the result, grains preserve their orientation to magnetic field when the magnetic field direction fluctuates. We point out to the importance of internal alignment, i.e. the process forces grain axes to be aligned in respect to the grain angular momentum. We show that subtle quantum effects, in particular relaxation related to nuclear magnetic moments of atoms composing the grain, brings to live complex grain motions, e.g. flips. These flips substantially alter the dynamics of grain and limit the applicability of earlier theories that did not account for them. We also briefly review basic physical processes involved in the alignment of grain angular momentum in respect to interstellar magnetic field. We claim that the bulk of existing observational data is consistent with the radiative torque alignment mechanism. In particular, we show that large grains that are known to exist in the cores of molecular clouds may be aligned by the attenuated external interstellar radiation field.

A. Lazarian; J. Cho

2004-08-10T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

First-principles investigations of Ni3Al(111) and NiAl(110) surfaces at metal dusting conditions  

SciTech Connect

We investigate the structure and surface composition of the {gamma}{prime}-Ni{sub 3}Al(111) and {beta}-NiAl(110) alloy surfaces at conditions relevant for metal dusting corrosion related to catalytic steam reforming of natural gas. In regular service as protective coatings, nickel-aluminum alloys are protected by an oxide scale, but in case of oxide scale spallation, the alloy surface may be directly exposed to the reactive gas environment and vulnerable to metal dusting. By means of density functional theory and thermochemical calculations for both the Ni{sub 3}Al and NiAl surfaces, the conditions under which CO and OH adsorption is to be expected and under which it is inhibited, are mapped out. Because CO and OH are regarded as precursors for nucleating graphite or oxide on the surfaces, phase diagrams for the surfaces provide a simple description of their stability. Specifically, this study shows how the CO and OH coverages depend on the steam to carbon ratio (S/C) in the gas and thereby provide a ranking of the carbon limits on the different surface phases.

Saadi, Souheil

2011-03-01T23:59:59.000Z

422

Sensitive glow discharge ion source for aerosol and gas analysis  

DOE Patents (OSTI)

A high sensitivity glow discharge ion source system for analyzing particles includes an aerodynamic lens having a plurality of constrictions for receiving an aerosol including at least one analyte particle in a carrier gas and focusing the analyte particles into a collimated particle beam. A separator separates the carrier gas from the analyte particle beam, wherein the analyte particle beam or vapors derived from the analyte particle beam are selectively transmitted out of from the separator. A glow discharge ionization source includes a discharge chamber having an entrance orifice for receiving the analyte particle beam or analyte vapors, and a target electrode and discharge electrode therein. An electric field applied between the target electrode and discharge electrode generates an analyte ion stream from the analyte vapors, which is directed out of the discharge chamber through an exit orifice, such as to a mass spectrometer. High analyte sensitivity is obtained by pumping the discharge chamber exclusively through the exit orifice and the entrance orifice.

Reilly, Peter T. A. (Knoxville, TN)

2007-08-14T23:59:59.000Z

423

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

73,669 73,669 141,300 1.59 221,822 1.12 3 0.10 46,289 0.88 33,988 1.24 31,006 0.98 252,585 1.26 A r k a n s a s Arkansas 51. Summary Statistics for Natural Gas Arkansas, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 1,750 1,552 1,607 1,563 1,470 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 3,500 3,500 3,500 3,988 4,020 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 171,543 166,273 161,967 161,390 182,895 From Oil Wells ........................................... 39,364 38,279 33,446 33,979 41,551 Total.............................................................. 210,906 204,552 195,413 195,369 224,446 Repressuring ................................................

424

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

-1,080,240 -1,080,240 201,024 2.27 1,734,887 8.78 133 4.54 76,629 1.46 136,436 4.99 46,152 1.46 460,373 2.30 O k l a h o m a Oklahoma 84. Summary Statistics for Natural Gas Oklahoma, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 13,926 13,289 13,487 13,438 13,074 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 28,902 29,118 29,121 29,733 29,733 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 1,674,405 1,732,997 1,626,858 1,521,857 1,467,695 From Oil Wells ........................................... 342,950 316,945 308,006 289,877 267,192 Total.............................................................. 2,017,356 2,049,942 1,934,864

425

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

7,038,115 7,038,115 3,528,911 39.78 13,646,477 69.09 183 6.24 408,861 7.80 1,461,718 53.49 281,452 8.91 5,681,125 28.40 West South Central West South Central 42. Summary Statistics for Natural Gas West South Central, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 87,198 84,777 88,034 88,734 62,357 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 92,212 95,288 94,233 102,525 102,864 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 11,599,913 11,749,649 11,959,444 11,824,788 12,116,665 From Oil Wells ........................................... 2,313,831 2,368,395 2,308,634 2,217,752 2,151,247 Total..............................................................

426

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

77,379 77,379 94,481 1.07 81,435 0.41 8 0.27 70,232 1.34 1,836 0.07 40,972 1.30 207,529 1.04 K e n t u c k y Kentucky 65. Summary Statistics for Natural Gas Kentucky, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 1,084 1,003 969 1,044 983 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 12,483 12,836 13,036 13,311 13,501 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 79,690 86,966 73,081 74,754 81,435 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. 79,690 86,966 73,081 74,754 81,435 Repressuring ................................................

427

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

-67,648 -67,648 75,616 0.85 480,828 2.43 0 0.00 16,720 0.32 31,767 1.16 29,447 0.93 153,549 0.77 Pacific Noncontiguous Pacific Noncontiguous 45. Summary Statistics for Natural Gas Pacific Noncontiguous, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 9,638 9,907 9,733 9,497 9,294 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 112 113 104 100 102 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 198,603 190,139 180,639 179,470 183,747 From Oil Wells ........................................... 2,427,110 2,588,202 2,905,261 3,190,433 3,189,837 Total.............................................................. 2,625,713 2,778,341

428

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

-310,913 -310,913 110,294 1.24 712,796 3.61 2 0.07 85,376 1.63 22,607 0.83 57,229 1.81 275,508 1.38 K a n s a s Kansas 64. Summary Statistics for Natural Gas Kansas, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 9,681 9,348 9,156 8,571 7,694 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 18,400 19,472 19,365 22,020 21,388 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 580,572 605,578 628,900 636,582 629,755 From Oil Wells ........................................... 79,169 82,579 85,759 86,807 85,876 Total.............................................................. 659,741 688,157 714,659 723,389 715,631 Repressuring ................................................

429

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

819,046 819,046 347,043 3.91 245,740 1.24 40 1.36 399,522 7.62 32,559 1.19 201,390 6.38 980,555 4.90 M i c h i g a n Michigan 70. Summary Statistics for Natural Gas Michigan, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 1,223 1,160 1,323 1,294 2,061 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 3,257 5,500 6,000 5,258 5,826 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 120,287 126,179 136,989 146,320 201,123 From Oil Wells ........................................... 80,192 84,119 91,332 97,547 50,281 Total.............................................................. 200,479 210,299 228,321 243,867 251,404 Repressuring ................................................

430

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

W W y o m i n g -775,410 50,253 0.57 666,036 3.37 14 0.48 13,534 0.26 87 0.00 9,721 0.31 73,609 0.37 Wyoming 98. Summary Statistics for Natural Gas Wyoming, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 10,826 10,933 10,879 12,166 12,320 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 3,111 3,615 3,942 4,196 4,510 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 751,693 880,596 949,343 988,671 981,115 From Oil Wells ........................................... 285,125 142,006 121,519 111,442 109,434 Total.............................................................. 1,036,817 1,022,602 1,070,862 1,100,113 1,090,549 Repressuring

431

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

-67,648 -67,648 75,616 0.85 480,828 2.43 0 0.00 16,179 0.31 31,767 1.16 27,315 0.86 150,877 0.75 A l a s k a Alaska 49. Summary Statistics for Natural Gas Alaska, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 9,638 9,907 9,733 9,497 9,294 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 112 113 104 100 102 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 198,603 190,139 180,639 179,470 183,747 From Oil Wells ........................................... 2,427,110 2,588,202 2,905,261 3,190,433 3,189,837 Total.............................................................. 2,625,713 2,778,341 3,085,900 3,369,904 3,373,584 Repressuring

432

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

628,189 628,189 449,511 5.07 765,699 3.88 100 3.41 528,662 10.09 39,700 1.45 347,721 11.01 1,365,694 6.83 West North Central West North Central 39. Summary Statistics for Natural Gas West North Central, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 10,177 9,873 9,663 9,034 8,156 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 18,569 19,687 19,623 22,277 21,669 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 594,551 626,728 651,594 655,917 648,822 From Oil Wells ........................................... 133,335 135,565 136,468 134,776 133,390 Total.............................................................. 727,886 762,293

433

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

1,048,760 1,048,760 322,661 3.64 18,131 0.09 54 1.84 403,264 7.69 142,688 5.22 253,075 8.01 1,121,742 5.61 N e w Y o r k New York 80. Summary Statistics for Natural Gas New York, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 329 264 242 197 232 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 5,906 5,757 5,884 6,134 6,208 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 22,697 20,587 19,937 17,677 17,494 From Oil Wells ........................................... 824 610 539 723 641 Total.............................................................. 23,521 21,197 20,476 18,400 18,134 Repressuring ................................................

434

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

1,554,530 1,554,530 311,229 3.51 3,094,431 15.67 442 15.08 299,923 5.72 105,479 3.86 210,381 6.66 927,454 4.64 Mountain Mountain 43. Summary Statistics for Natural Gas Mountain, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 38,711 38,987 37,366 39,275 38,944 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 30,965 34,975 38,539 38,775 41,236 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 2,352,729 2,723,393 3,046,159 3,131,205 3,166,689 From Oil Wells ........................................... 677,771 535,884 472,397 503,986 505,903 Total.............................................................. 3,030,499 3,259,277 3,518,556

435

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

1,592,465 1,592,465 716,648 8.08 239,415 1.21 182 6.21 457,792 8.73 334,123 12.23 320,153 10.14 1,828,898 9.14 South Atlantic South Atlantic 40. Summary Statistics for Natural Gas South Atlantic, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 3,307 3,811 4,496 4,427 4,729 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 39,412 35,149 41,307 37,822 36,827 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 206,766 208,892 234,058 236,072 233,409 From Oil Wells ........................................... 7,584 8,011 8,468 7,133 6,706 Total.............................................................. 214,349 216,903 242,526 243,204 240,115

436

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

1,999,161 1,999,161 895,529 10.10 287,933 1.46 1,402 47.82 569,235 10.86 338,640 12.39 308,804 9.78 2,113,610 10.57 Pacific Contiguous Pacific Contiguous 44. Summary Statistics for Natural Gas Pacific Contiguous, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 3,896 3,781 3,572 3,508 2,082 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 1,142 1,110 1,280 1,014 996 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... 156,635 124,207 117,725 96,329 88,173 From Oil Wells ........................................... 294,800 285,162 282,227 289,430 313,581 Total.............................................................. 451,435 409,370

437

Natural Gas  

Gasoline and Diesel Fuel Update (EIA)

-122,394 -122,394 49,997 0.56 178,984 0.91 5 0.17 37,390 0.71 205 0.01 28,025 0.89 115,622 0.58 West Virginia West Virginia 96. Summary Statistics for Natural Gas West Virginia, 1992-1996 Table 1992 1993 1994 1995 1996 Reserves (billion cubic feet) Estimated Proved Reserves (dry) as of December 31 ....................................... 2,356 2,439 2,565 2,499 2,703 Number of Gas and Gas Condensate Wells Producing at End of Year.............................. 38,250 33,716 39,830 36,144 35,148 Production (million cubic feet) Gross Withdrawals From Gas Wells ......................................... E 182,000 171,024 183,773 186,231 178,984 From Oil Wells ........................................... 0 0 0 0 0 Total.............................................................. E 182,000 171,024 183,773 186,231 178,984 Repressuring ................................................

438

Gas vesicles.  

Science Journals Connector (OSTI)

...the gas vesicles simply reduce their sinking rates and...remaining suspended in the water column. A microorganism...phenomena as stratification, water- bloom formation, and...the many proteins that make up the phycobilisome (73...flagellate bacteria in natural waters. The natural selection...

A E Walsby

1994-03-01T23:59:59.000Z

439

Gas vesicles.  

Science Journals Connector (OSTI)

...these costs can be compared is in units of energy expenditure per time (joules per second...requires 7.24 x 10-18 kg of Gvp. The energy cost of making this protein, Eg, is...Eg = 2.84 x 101- o J. The rate of energy expenditure in gas vesicle synthesis then...

A E Walsby

1994-03-01T23:59:59.000Z

440

Gas sensor  

DOE Patents (OSTI)

A gas sensor is described which incorporates a sensor stack comprising a first film layer of a ferromagnetic material, a spacer layer, and a second film layer of the ferromagnetic material. The first film layer is fabricated so that it exhibits a dependence of its magnetic anisotropy direction on the presence of a gas, That is, the orientation of the easy axis of magnetization will flip from out-of-plane to in-plane when the gas to be detected is present in sufficient concentration. By monitoring the change in resistance of the sensor stack when the orientation of the first layer's magnetization changes, and correlating that change with temperature one can determine both the identity and relative concentration of the detected gas. In one embodiment the stack sensor comprises a top ferromagnetic layer two mono layers thick of cobalt deposited upon a spacer layer of ruthenium, which in turn has a second layer of cobalt disposed on its other side, this second cobalt layer in contact with a programmable heater chip.

Schmid, Andreas K.; Mascaraque, Arantzazu; Santos, Benito; de la Figuera, Juan

2014-09-09T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Existence State of Bromine as an Indicator of the Source of Brominated Flame Retardants in Indoor Dust  

Science Journals Connector (OSTI)

We used micro XRFS and gas chromatography-high resolution mass spectrometry (GC-HRMS) to elucidate the exsistence state of bromine as an indicator of the source of BFRs in dust samples collected in Japan from households, offices in universities and other institutions, highly flame-retarded facilities which comply with the Fire Service Law of Japan, and the interior of TVs. ... Our recent research also revealed that household products containing more than 0.01% bromine are present in Japanese households (20) and business hotels (21). ...

Go Suzuki; Akiko Kida; Shin-ichi Sakai; Hidetaka Takigami

2009-02-02T23:59:59.000Z

442

Particle Physics Booklet 2008  

E-Print Network (OSTI)

212 25. Accelerator physics of colliders ? 26. High-energythe full Review. PARTICLE PHYSICS BOOKLET TABLE OF CONTENTSrev. ) Summary Tables of Particle Physics Gauge and Higgs

et al., C. Amsler

2008-01-01T23:59:59.000Z

443

Nuclear and Particle Futures  

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

Nuclear and Particle Futures Nuclear and Particle Futures The Lab's four Science Pillars harness capabilities for solutions to threats- on national and global scales. Contacts...

444

Evolution of the dust emission of massive galaxies up to z=4 and constraints on their dominant mode of star formation  

E-Print Network (OSTI)

We aim to measure the average dust and molecular gas content of massive star-forming galaxies ($\\rm > 3 \\times 10^{10}\\,M_\\odot$) up to z=4 in the COSMOS field to determine if the intense star formation observed at high redshift is induced by major mergers or caused by large gas reservoirs. Firstly, we measured the evolution of the average spectral energy distributions as a function of redshift using a stacking analysis of Spitzer, Herschel, LABOCA, and AzTEC data for two samples of galaxies: normal star-forming objects and strong starbursts, as defined by their distance to the main sequence. We found that the mean intensity of the radiation field $\\langle U \\rangle$ heating the dust (strongly correlated with dust temperature) increases with increasing redshift up to z$\\sim$4 in main-sequence galaxies. We can reproduce this evolution with simple models that account for the decrease of the gas metallicity with redshift. No evolution of $\\langle U \\rangle$ with redshift is found in strong starbursts. We then de...

Béthermin, Matthieu; Magdis, Georgios; Lagos, Claudia; Sargent, Mark; Albrecht, Marcus; Aussel, Hervé; Bertoldi, Frank; Buat, Véronique; Galametz, Maud; Heinis, Sébastien; Karim, Alexander; Koekemoer, Anton; Lacey, Cedric; Floc'h, Emeric Le; Navarrete, Felipe; Pannella, Maurilio; Schreiber, Corentin; Symeonidis, Myrto; Viero, Marco

2014-01-01T23:59:59.000Z

445

Liquid Natural Gas  

Science Journals Connector (OSTI)

Liquid Natural Gas ... IN A new technique for storing natural gas at the East Ohio Gas Co. plant, Cleveland, Ohio, the gas is liquefied before passing to the gas holders. ... Natural gas contains moisture and carbon dioxide, both of which liquefy before the natural gas and are somewhat of a nuisance because upon solidification they clog the pipes. ...

W. F. SCHAPHORST

1941-04-25T23:59:59.000Z

446

Process to make structured particles  

DOE Patents (OSTI)

Disclosed is a process for making a composite material that contains structured particles. The process includes providing a first precursor in the form of a dry precursor powder, a precursor liquid, a precursor vapor of a liquid and/or a precursor gas. The process also includes providing a plasma that has a high field zone and passing the first precursor through the high field zone of the plasma. As the first precursor passes through the high field zone of the plasma, at least part of the first precursor is decomposed. An aerosol having a second precursor is provided downstream of the high field zone of the plasma and the decomposed first material is allowed to condense onto the second precursor to from structured particles.

Knapp, Angela Michelle; Richard, Monique N; Luhrs, Claudia; Blada, Timothy; Phillips, Jonathan

2014-02-04T23:59:59.000Z

447

A New Determination of the Binding Energy of Atomic Oxygen on Dust Grain Surfaces: Experimental Results and Simulations  

E-Print Network (OSTI)

The energy to desorb atomic oxygen from an interstellar dust grain surface, $E_{\\rm des}$, is an important controlling parameter in gas-grain models; its value impacts the temperature range over which oxygen resides on a dust grain. However, no prior measurement has been done of the desorption energy. We report the first direct measurement of $E_{\\rm des}$ for atomic oxygen from dust grain analogs. The values of $E_{\\rm des}$ are $1660\\pm 60$~K and $1850\\pm 90$~K for porous amorphous water ice and for a bare amorphous silicate film, respectively, or about twice the value previously adopted in simulations of the chemical evolution of a cloud. We use the new values to study oxygen chemistry as a function of depth in a molecular cloud. For $n=10^4$ cm$^{-3}$ and $G_0$=10$^2$ ($G_0$=1 is the average local interstellar radiation field), the main result of the adoption of the higher oxygen binding energy is that H$_2$O can form on grains at lower visual extinction $A_{\\rm V}$, closer to the cloud surface. A higher ...

He, Jiao; Hopkins, Tyler; Vidali, Gianfranco; Kaufman, Michael J

2015-01-01T23:59:59.000Z

448

Membrane based apparatus for measurement of volatile particles  

SciTech Connect

A vapor particle separator including a temperature controlled chamber for desorbing vapors from the particulates of an exhaust gas and a separation chamber including a micro porous membrane. The micro porous membrane provides an interface between at least one particle passageway and at least one vapor passageway through the separation chamber. The particle passageway extends from an entrance to the separation chamber to a particle exit from the separation chamber. The vapor passageway extends from the micro-porous membrane to a vapor exit from the separation chamber that is separate from the particle exit from the separation chamber.

Cheng, Meng-Dawn; Allman, Steve L.

2014-07-08T23:59:59.000Z

449

NATURAL GAS MARKET ASSESSMENT  

E-Print Network (OSTI)

CALIFORNIA ENERGY COMMISSION NATURAL GAS MARKET ASSESSMENT PRELIMINARY RESULTS In Support.................................................................................... 6 Chapter 2: Natural Gas Demand.................................................................................................. 10 Chapter 3: Natural Gas Supply

450

,"Missouri Natural Gas Summary"  

U.S. Energy Information Administration (EIA) Indexed Site

Gas Sold to Commercial Consumers (Dollars per Thousand Cubic Feet)","Missouri Natural Gas Industrial Price (Dollars per Thousand Cubic Feet)","Missouri Natural Gas Price Sold to...

451

Natural Gas Weekly Update  

Annual Energy Outlook 2012 (EIA)

natural gas production output. Rigs Natural Gas Transportation Update Tennessee Gas Pipeline Company yesterday (August 4) said it is mobilizing equipment and manpower for...

452

Coke battery with 51-m{sup 3} furnace chambers and lateral supply of mixed gas  

SciTech Connect

The basic approaches employed in the construction of coke battery 11A at OAO Magnitogorskii Metallurgicheskii Kombinat are outlined. This battery includes 51.0-m{sup 3} furnaces and a dust-free coke-supply system designed by Giprokoks with lateral gas supply; it is heated exclusively by low-calorific mixed gas consisting of blast-furnace gas with added coke-oven gas. The 82 furnaces in the coke battery are divided into two blocks of 41. The gross coke output of the battery (6% moisture content) is 1140000 t/yr.

V.I. Rudyka; N.Y. Chebotarev; O.N. Surenskii; V.V. Derevich [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

2009-07-15T23:59:59.000Z

453

Shale gas is natural gas trapped inside  

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

Shale gas is natural gas trapped inside formations of shale - fine grained sedimentary rocks that can be rich sources of petroleum and natural gas. Just a few years ago, much of...

454

Capture of particles of dust by convective flow Dmitry V. Lyubimov  

E-Print Network (OSTI)

is essential in lowering fuel consumption during combustion of liquid fuels. In biology, recent developments medium.3­5 A typical example is algae, transported by ocean flows. These algae contribute essentially

Straube, Arthur V.

455

Thermal instability in molecular clouds, including dust particles, Hall effect and ambipolar diffusion  

Science Journals Connector (OSTI)

......not significantly affect the diagram. By increasing to higher values, the diagram tends to isentropic mode. Therefore...and Hall diffusion to ideal MHD equations. We have also considered...instability. First, we considered MHD equations for partially ionized......

A. R. Khesali; S. M. Ghoreyshi; M. Nejad-Asghar

2012-03-01T23:59:59.000Z

456

Heterogeneous chemistry of atmospheric mineral dust particles and their resulting cloud-nucleation properties  

E-Print Network (OSTI)

2 O), as well as soluble halite (NaCl) salts (Jeong, 2008;2 O), as well as soluble halite (NaCl) salts (Jeong, 2008;source as minerals such as halite (NaCl) and gypsum (CaSO

Sullivan, Ryan Christopher

2008-01-01T23:59:59.000Z

457

Evidence for interstellar origin of seven dust particles collected by the Stardust spacecraft  

Science Journals Connector (OSTI)

...Planet. Sci. 10.1111/maps.12219 (2014). 19...Planet. Sci. 10.1111/maps.12136 (2014). 20...Planet. Sci. 10.1111/maps.12221 (2014). 21...stability of the interstellar wind through the solar system...impacts on Al-1100 foil at velocities up to 300 km s -1 and validation...

Andrew J. Westphal; Rhonda M. Stroud; Hans A. Bechtel; Frank E. Brenker; Anna L. Butterworth; George J. Flynn; David R. Frank; Zack Gainsforth; Jon K. Hillier; Frank Postberg; Alexandre S. Simionovici; Veerle J. Sterken; Larry R. Nittler; Carlton Allen; David Anderson; Asna Ansari; Saša Bajt; Ron K. Bastien; Nabil Bassim; John Bridges; Donald E. Brownlee; Mark Burchell; Manfred Burghammer; Hitesh Changela; Peter Cloetens; Andrew M. Davis; Ryan Doll; Christine Floss; Eberhard Grün; Philipp R. Heck; Peter Hoppe; Bruce Hudson; Joachim Huth; Anton Kearsley; Ashley J. King; Barry Lai; Jan Leitner; Laurence Lemelle; Ariel Leonard; Hugues Leroux; Robert Lettieri; William Marchant; Ryan Ogliore; Wei Jia Ong; Mark C. Price; Scott A. Sandford; Juan-Angel Sans Tresseras; Sylvia Schmitz; Tom Schoonjans; Kate Schreiber; Geert Silversmit; Vicente A. Solé; Ralf Srama; Frank Stadermann; Thomas Stephan; Julien Stodolna; Stephen Sutton; Mario Trieloff; Peter Tsou; Tolek Tyliszczak; Bart Vekemans; Laszlo Vincze; Joshua Von Korff; Naomi Wordsworth; Daniel Zevin; Michael E. Zolensky; 30714 Stardust@home dusters

2014-08-15T23:59:59.000Z

458

Oxygen isotopic composition of chondritic interplanetary dust particles: A genetic link between carbonaceous chondrites and  

E-Print Network (OSTI)

a Lawrence Livermore National Laboratory, Glenn T. Seaborg Institute, P.O. Box 808, Livermore, CA 94550, USA

459

Particle Creation in a Universe Filled with Radiation and Dust-Like Matter  

Science Journals Connector (OSTI)

......solution can be expressed in terms of confluent hypergeometric functions M(a, b, z) and U(a, b, Z)ll) as follows: + C2U( ~ +c+ibm, 2c+1, 2ibme~)), (2 9) where Cl and C2 are arbitrary constants and C is given by the expression (2 10......

Víctor M. Villalba

1993-09-01T23:59:59.000Z

460

Asian dust particles converted into aqueous droplets under remote marine atmospheric conditions  

Science Journals Connector (OSTI)

...n = 7), Sado-seki (n = 7), and Tappi (n = 7) from March to May 2007 (means...Site II); and Oki, Sado-seki and Tappi, which are located east of the Sea of...Kanghwa, Imsil, Oki, Sado-seki, and Tappi from March to May 2007. Note: if ambient...

Yutaka Tobo; Daizhou Zhang; Atsushi Matsuki; Yasunobu Iwasaka

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dust particles gas" 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

Gas Chromatography  

Science Journals Connector (OSTI)

Researchers from the University of Missouri and ICx Nomadics have reported on the use of a optofluidic ring resonator (OFRR) sensor for on-column detection ?. ... Although substantial differences were noted between fresh and aged (or oxidized) oils, many of the compounds in the oxidized oil went unidentified due to lack of library mass spectral data. ... A high resolution MEMS based gas chromatography column for the analysis of benzene and toluene gaseous mixtures ...

Frank L. Dorman; Joshua J. Whiting; Jack W. Cochran; Jorge Gardea-Torresdey

2010-05-26T23:59:59.000Z