National Library of Energy BETA

Sample records for matter dust smoke

  1. Glaciation temperatures of convective clouds ingesting desert dust, air pollution and smoke from forest fires

    E-Print Network [OSTI]

    Daniel, Rosenfeld

    Glaciation temperatures of convective clouds ingesting desert dust, air pollution and smoke from observations show that desert dust and heavy air pollution over East Asia have similar ability to glaciate desert dust, air pollution and smoke from forest fires, Geophys. Res. Lett., 38, L21804, doi:10

  2. Searching for Smoking Gun Signatures of Decaying Dark Matter

    E-Print Network [OSTI]

    Joshua T. Ruderman; Tomer Volansky

    2009-08-11

    Clear methods to differentiate between decaying and annihilating dark matter (DM) scenarios are still by and large unavailable. In this note, we study the potential astrophysical signatures of a new class of hidden sector decaying DM models, which can address the recent cosmic ray measurements. Such models may produce primary photons and/or neutrinos at large rates, correlated with the leptonic production. The photon and neutrino spectra will then contain sharp features at the TeV scale. We demonstrate the discovery potential for upcoming and future measurements by FERMI, HESS, AGIS and IceCube/DeepCore. We show that these models may be discovered in the near future. Specifically, measurements of diffuse gamma rays by FERMI can detect the start of a hard photon feature. We argue that these hard spectra can be produced by decaying dark matter and be consistent with current constraints, but are difficult to reconcile with models of annihilating DM. Consequently the measurement of a hard spectral feature, in correlation with the current cosmic ray measurements, will strongly favor decaying DM models. Finally we comment on the preliminary results from the Inner Galaxy presented by the FERMI collaboration.

  3. The positron excess as a smoking gun for dynamical dark matter?

    SciTech Connect (OSTI)

    Dienes, Keith R.; Kumar, Jason; Thomas, Brooks

    2014-06-24

    One of the most puzzling aspects of recent data from the AMS-02 experiment is an apparent rise in the cosmic-ray positron fraction as a function of energy. This feature is observed out to energies of approximately 350 GeV. One explanation of these results interprets the extra positrons as arising from the decays of dark-matter particles. This in turn typically requires that such particles have rather heavy TeV-scale masses and not undergo simple two-body decays to leptons. In this talk, by contrast, we show that Dynamical Dark Matter (DDM) can not only match existing AMS-02 data on the positron excess, but also accomplish this feat with significantly lighter dark-matter constituents undergoing simple two-body decays to leptons. We also demonstrate that the Dynamical Dark Matter framework makes a fairly robust prediction that the positron fraction should level off and then remain roughly constant out to approximately 1 TeV, without experiencing any sharp downturns. Thus, if we interpret the positron excess in terms of decaying dark matter, the existence of a plateau in the positron fraction at energies less than 1 TeV may be taken as a “smoking gun” of Dynamical Dark Matter.

  4. Dark Photons from the Center of the Earth: Smoking-Gun Signals of Dark Matter

    E-Print Network [OSTI]

    Jonathan L. Feng; Jordan Smolinsky; Philip Tanedo

    2015-09-24

    Dark matter may be charged under dark electromagnetism with a dark photon that kinetically mixes with the Standard Model photon. In this framework, dark matter will collect at the center of the Earth and annihilate into dark photons, which may reach the surface of the Earth and decay into observable particles. We determine the resulting signal rates, including Sommerfeld enhancements, which play an important role in bringing the Earth's dark matter population to their maximal, equilibrium value. For dark matter masses $m_X \\sim$ 100 GeV - 10 TeV, dark photon masses $m_{A'} \\sim$ MeV - GeV, and kinetic mixing parameters $\\varepsilon \\sim 10^{-9} - 10^{-7}$, the resulting electrons, muons, photons, and hadrons that point back to the center of the Earth are a smoking-gun signal of dark matter that may be detected by a variety of experiments, including neutrino telescopes, such as IceCube, and space-based cosmic ray detectors, such as Fermi-LAT and AMS. We determine the signal rates and characteristics, and show that large and striking signals---such as parallel muon tracks---are possible in regions of the $(m_{A'}, \\varepsilon)$ plane that are not probed by direct detection, accelerator experiments, or astrophysical observations.

  5. Dark Photons from the Center of the Earth: Smoking-Gun Signals of Dark Matter

    E-Print Network [OSTI]

    Feng, Jonathan L; Tanedo, Philip

    2015-01-01

    Dark matter may be charged under dark electromagnetism with a dark photon that kinetically mixes with the Standard Model photon. In this framework, dark matter will collect at the center of the Earth and annihilate into dark photons, which may reach the surface of the Earth and decay into observable particles. We determine the resulting signal rates, including Sommerfeld enhancements, which play an important role in bringing the Earth's dark matter population to their maximal, equilibrium value. For dark matter masses $m_X \\sim$ 100 GeV - 10 TeV, dark photon masses $m_{A'} \\sim$ MeV - GeV, and kinetic mixing parameters $\\varepsilon \\sim 10^{-9} - 10^{-7}$, the resulting electrons, muons, photons, and hadrons that point back to the center of the Earth are a smoking-gun signal of dark matter that may be detected by a variety of experiments, including neutrino telescopes, such as IceCube, and space-based cosmic ray detectors, such as Fermi-LAT and AMS. We determine the signal rates and characteristics, and show ...

  6. Smoke Signals From IRC +10216: 1. Milliarcsecond Proper Motions of the Dust

    E-Print Network [OSTI]

    P. G. Tuthill; J. D. Monnier; W. C. Danchi; B. Lopez

    2000-03-21

    The results of a 7-epoch interferometric imaging study, at wavelengths in the near-infrared K-band, of the carbon star IRC +10216 are presented. The use of non- and partially-redundant aperture masking techniques on the 10-m Keck-I telescope has allowed us to produce images of the innermost regions of the circumstellar dust envelope with unprecedented detail. With roughly twice the resolving power of previous work, the complex asymmetric structures reported within the central 0.5 arcsec (20 stellar radii) have been imaged at the size scale of the stellar disk itself (about 50 mas). A prominent dark lane at a position angle of approximately 120 deg is suggested to be an optically thick disk or torus of dust which could help to explain IRC +10216's well-known bipolarity at a position angle of 20 deg. Observations spanning more than a pulsational cycle (638 days) have revealed significant temporal evolution of the nebula, including the outward motion of bright knots and clumps. Registering these displacements against the compact bright core, which we tentatively identify as marking the location of the star, has allowed us to determine the apparent angular velocity at a number of points. The magnitudes of the proper motions were found to be in agreement with current estimates of the stellar distance and radial velocity. Higher outflow speeds were found for features with greater separation from the core. This is consistent with acceleration taking place over the region sampled by the measurements, however alternate interpretations are also presented. Although a number of changes of morphology were found, none were clearly interpreted as the condensation of new dust over the pulsation cycle.

  7. Dark Matter Decay to a Photon and a Neutrino: the Double Monochromatic Smoking Gun Scenario

    E-Print Network [OSTI]

    Chaïmae El Aisati; Michael Gustafsson; Thomas Hambye; Tiziana Scarna

    2015-10-16

    In the energy range from few TeV to 25 TeV, upper bounds on the dark matter decay rate into high energy monochromatic neutrinos have recently become comparable to those on monochromatic gamma-ray lines. This implies clear possibilities of a future double "smoking-gun" evidence for the dark matter particle, from the observation of both a gamma and a neutrino line at the same energy. In particular, we show that a scenario where both lines are induced from the same dark matter particle decay leads to correlations that can already be tested. We study this "double monochromatic" scenario by considering the complete list of lowest dimensional effective operators that could induce such a decay. Furthermore, we argue that, on top of lines from decays into two-body final states, three-body final states can also be highly relevant. In addition to producing a distinct hard photon spectrum, three-body final states also produce a line-like feature in the neutrino spectrum that can be searched for by neutrino telescopes.

  8. Dark Matter Decay to a Photon and a Neutrino: the Double Monochromatic Smoking Gun Scenario

    E-Print Network [OSTI]

    Aisati, Chaïmae El; Hambye, Thomas; Scarna, Tiziana

    2015-01-01

    In the energy range from few TeV to 25 TeV, upper bounds on the dark matter decay rate into high energy monochromatic neutrinos have recently become comparable to those on monochromatic gamma-ray lines. This implies clear possibilities of a future double "smoking-gun" evidence for the dark matter particle, from the observation of both a gamma and a neutrino line at the same energy. In particular, we show that a scenario where both lines are induced from the same dark matter particle decay leads to correlations that can already be tested. We study this "double monochromatic" scenario by considering the complete list of lowest dimensional effective operators that could induce such a decay. Furthermore, we argue that, on top of lines from decays into two-body final states, three-body final states can also be highly relevant. In addition to producing a distinct hard photon spectrum, three-body final states also produce a line-like feature in the neutrino spectrum that can be searched for by neutrino telescopes.

  9. From flux to dust mass: Does the grain-temperature distribution matter for estimates of cold dust masses in supernova remnants?

    E-Print Network [OSTI]

    Mattsson, Lars; Andersen, Anja C; Matsuura, Mikako

    2015-01-01

    The amount of dust estimated from infrared to sub-millimetre (submm) observations strongly depends on assumptions of different grain sizes, compositions and optical properties. Here we use a simple model of thermal emission from cold silicate/carbon dust at a range of dust grain temperatures and fit the spectral energy distribution (SED) of the Crab Nebula as a test. This can lower the derived dust mass for the Crab by ~50% and 30-40% for astronomical silicates and amorphous carbon grains compared to recently published values (0.25M_sun -> 0.12M_sun and 0.12M_sun -> 0.072M_sun, respectively), but the implied dust mass can also increase by as much as almost a factor of six (0.25M_sun -> 1.14M_sun and 0.12M_sun -> 0.71M_sun) depending on assumptions regarding the sizes/temperatures of the coldest grains. The latter values are clearly unrealistic due to the expected metal budget, though. Furthermore, we show by a simple numerical experiment that if a cold-dust component does have a grain-temperature distribution...

  10. Interpretation of variations in fine, coarse and black smoke particulate matter concentrations in a Northern European city 

    E-Print Network [OSTI]

    Heal, Mathew R; Hibbs, Leon; Agius, Raymond M; Beverland, Iain J

    2005-01-01

    The PM2.5, PMcoarse and black smoke (BS) particle metrics broadly reflect different source contributions to PM10. The aim of this study was to generate data for PM2.5 at an urban background site in the UK, and to use the daily collocated measurement...

  11. Smoke detection

    SciTech Connect (OSTI)

    Warmack, Robert J. Bruce; Wolf, Dennis A.; Frank, Steven Shane

    2015-10-27

    Various apparatus and methods for smoke detection are disclosed. In one embodiment, a method of training a classifier for a smoke detector comprises inputting sensor data from a plurality of tests into a processor. The sensor data is processed to generate derived signal data corresponding to the test data for respective tests. The derived signal data is assigned into categories comprising at least one fire group and at least one non-fire group. Linear discriminant analysis (LDA) training is performed by the processor. The derived signal data and the assigned categories for the derived signal data are inputs to the LDA training. The output of the LDA training is stored in a computer readable medium, such as in a smoke detector that uses LDA to determine, based on the training, whether present conditions indicate the existence of a fire.

  12. Smoke detection

    SciTech Connect (OSTI)

    Warmack, Robert J Bruce; Wolf, Dennis A.; Frank, Steven Shane

    2015-11-05

    Various apparatus and methods for smoke detection are disclosed. In one embodiment, a method of training a classifier for a smoke detector comprises inputting sensor data from a plurality of tests into a processor. The sensor data is processed to generate derived signal data corresponding to the test data for respective tests. The derived signal data is assigned into categories comprising at least one fire group and at least one non-fire group. Linear discriminant analysis (LDA) training is performed by the processor. The derived signal data and the assigned categories for the derived signal data are inputs to the LDA training. The output of the LDA training is stored in a computer readable medium, such as in a smoke detector that uses LDA to determine, based on the training, whether present conditions indicate the existence of a fire.

  13. Measurement of organophosphate pesticides, organochlorine pesticides, and polycyclic aromatic hydrocarbons in household dust from two rural villages in Nepal 

    E-Print Network [OSTI]

    Cizmas, Leslie; Ackerman, Lani; Donnelly, Danielle A.; Donnelly, Kirby C.; McDonald, Thomas J.

    2015-01-16

    to polycyclic aromatic hydrocarbons from wood smoke. This study measured the levels of four organophosphate pesticides, 22 organochlorine pesticides, and over thirty polycyclic aromatic hydrocarbons in house dust from two rural Nepali villages. Floor dust...

  14. The Sky in Dust -- Methods and Prospects of Dust Astronomy

    E-Print Network [OSTI]

    M. Landgraf; E. Grün; R. Srama; S. Helfert; S. Kempf; G. Morgas-Klostermeyer; M. Rachev; A. Srowig; S. Auer; M. Horànyi; Z. Sternovsky; D. Harris

    2006-02-05

    Information about the make-up of the galaxy arrives in the Solar system in many forms: photons of different energies, classically collected by ground- and space-based telescopes, neutral and charged atomic particles, and solid macroscopic particles: cosmic dust particles. Dust particles, like photons, carry information from remote sites in space and time. This information can be analysed in order to understand the processes and mechanisms that are involved in the formation and evolution of solid matter in the galaxy. This approach is called ``Dust Astronomy'' which is carried out by means of a dust telescope on a dust observatory in space. The analysis of cosmic grains collected in the high atmosphere of the Earth has shown that each dust grain is a small world with various sub-grains featuring different galactic origin and evolution, which is identified on the basis of elementary and isotopic analysis. Independent information about the origin and evolution of the grains coming from the kinematic properties of the arrival trajectory would be invaluable for linking the isotopic signature of the formation of heavy elements in old stars and supernovae to distinctive regions in our galaxy, e.g. known star-forming regions. Here we present a skymap of potential dust sources together with a report on already existing lab hardware of a trajectory sensor and a large-area mass spectrometre.

  15. Smart smoke alarm

    SciTech Connect (OSTI)

    Warmack, Robert J. Bruce; Wolf, Dennis A; Frank, Steven Shane

    2015-04-28

    Methods and apparatus for smoke detection are disclosed. In one embodiment, a smoke detector uses linear discriminant analysis (LDA) to determine whether observed conditions indicate that an alarm is warranted.

  16. Evaluating the Effectiveness of Smoke-free Policies

    E-Print Network [OSTI]

    IARC World Health Organization

    2009-01-01

    cigarette smoking, household passive smoke exposure, and the2004). Active smoking, household passive smoking, and breastsecondhand smoking, passive smoking, household smok- ing,

  17. Dust Measurements in Tokamaks

    SciTech Connect (OSTI)

    Rudakov, D; Yu, J; Boedo, J; Hollmann, E; Krasheninnikov, S; Moyer, R; Muller, S; Yu, A; Rosenberg, M; Smirnov, R; West, W; Boivin, R; Bray, B; Brooks, N; Hyatt, A; Wong, C; Fenstermacher, M; Groth, M; Lasnier, C; McLean, A; Stangeby, P; Ratynskaia, S; Roquemore, A; Skinner, C; Solomon, W M

    2008-04-23

    Dust production and accumulation impose safety and operational concerns for ITER. Diagnostics to monitor dust levels in the plasma as well as in-vessel dust inventory are currently being tested in a few tokamaks. Dust accumulation in ITER is likely to occur in hidden areas, e.g. between tiles and under divertor baffles. A novel electrostatic dust detector for monitoring dust in these regions has been developed and tested at PPPL. In DIII-D tokamak dust diagnostics include Mie scattering from Nd:YAG lasers, visible imaging, and spectroscopy. Laser scattering resolves size of particles between 0.16-1.6 {micro}m in diameter; the total dust content in the edge plasmas and trends in the dust production rates within this size range have been established. Individual dust particles are observed by visible imaging using fast-framing cameras, detecting dust particles of a few microns in diameter and larger. Dust velocities and trajectories can be determined in 2D with a single camera or 3D using multiple cameras, but determination of particle size is problematic. In order to calibrate diagnostics and benchmark dust dynamics modeling, pre-characterized carbon dust has been injected into the lower divertor of DIII-D. Injected dust is seen by cameras, and spectroscopic diagnostics observe an increase of carbon atomic, C2 dimer, and thermal continuum emissions from the injected dust. The latter observation can be used in the design of novel dust survey diagnostics.

  18. Evaluation of the characterization of smoke plumes within the AIRPACT model

    E-Print Network [OSTI]

    Collins, Gary S.

    are a major source of air pollution during the fire season in the Western US, yet are not well characterized within air quality forecasting models. It is increasingly important to improve modeling of smoke plumes of particulate matter during the fire season, it is important to correctly characterize smoke plumes within air

  19. Shock Interaction with Dust Layers 

    E-Print Network [OSTI]

    Chowdhury, Amira Yousuf

    2015-06-02

    Dust explosion hazards in areas where combustible dusts are found have caused loss of life and halted business operations in some instances. The elimination of secondary dust explosion hazards, i.e. reducing dust dispersion, ...

  20. Niamey Dust Observations

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

    Flynn, Connor

    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.

  1. Niamey Dust Observations

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

    Flynn, Connor

    2008-10-01

    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.

  2. DUST FORMATION IN MACRONOVAE

    SciTech Connect (OSTI)

    Takami, Hajime; Ioka, Kunihito [Institute of Particle and Nuclear Studies, KEK, 1-1, Oho, Tsukuba 305-0801 (Japan); Nozawa, Takaya, E-mail: takami@post.kek.jp, E-mail: kunihito.ioka@kek.jp, E-mail: takaya.nozawa@nao.ac.jp [National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)

    2014-07-01

    We examine dust formation in macronovae (as known as kilonovae), which are the bright ejecta of neutron star binary mergers and one of the leading sites of r-process nucleosynthesis. In light of information about the first macronova candidate associated with GRB 130603B, we find that dust grains of r-process elements have difficulty forming because of the low number density of the r-process atoms, while carbon or elements lighter than iron can condense into dust if they are abundant. Dust grains absorb emission from ejecta with an opacity even greater than that of the r-process elements, and re-emit photons at infrared wavelengths. Such dust emission can potentially account for macronovae without r-process nucleosynthesis as an alternative model. This dust scenario predicts a spectrum with fewer features than the r-process model and day-scale optical-to-ultraviolet emission.

  3. Modified Dust and the Small Scale Crisis in CDM

    E-Print Network [OSTI]

    Fabio Capela; Sabir Ramazanov

    2015-04-29

    At large scales and for sufficiently early times, dark matter is described as a pressureless perfect fluid---dust---non-interacting with Standard Model fields. These features are captured by a simple model with two scalars: a Lagrange multiplier and another playing the role of the velocity potential. That model arises naturally in some gravitational frameworks, e.g., the mimetic dark matter scenario. We consider an extension of the model by means of higher derivative terms, such that the dust solutions are preserved at the background level, but there is a non-zero sound speed at the linear level. We associate this {\\it Modified Dust} with dark matter, and study the linear evolution of cosmological perturbations in that picture. The most prominent effect is the suppression of their power spectrum for sufficiently large cosmological momenta. This can be relevant in view of the problems that cold dark matter faces at sub-galactic scales, e.g., the missing satellites problem. At even shorter scales, however, perturbations of Modified Dust are enhanced compared to the predictions of more common particle dark matter scenarios. This is a peculiarity of their evolution in radiation dominated background. We also briefly discuss clustering of Modified Dust. We write the system of equations in the Newtonian limit, and sketch the possible mechanism which could prevent the appearance of caustic singularities. The same mechanism may be relevant in light of the core-cusp problem.

  4. Dust around Type Ia supernovae

    E-Print Network [OSTI]

    Wang, Lifan

    2005-01-01

    Dust around Type Ia supernovae Lifan Wang 1,2 LawrenceIa. Subject headings: Supernovae: General, Dust, Extinctionline) bands for Type Ia supernovae. (a), upper panel, shows

  5. Dust resuspension as a contaminant source and transport pathway

    SciTech Connect (OSTI)

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

    1999-07-01

    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.

  6. Newton to Einstein — dust to dust

    SciTech Connect (OSTI)

    Kopp, Michael; Uhlemann, Cora; Haugg, Thomas E-mail: cora.uhlemann@physik.lmu.de

    2014-03-01

    We investigate the relation between the standard Newtonian equations for a pressureless fluid (dust) and the Einstein equations in a double expansion in small scales and small metric perturbations. We find that parts of the Einstein equations can be rewritten as a closed system of two coupled differential equations for the scalar and transverse vector metric perturbations in Poisson gauge. It is then shown that this system is equivalent to the Newtonian system of continuity and Euler equations. Brustein and Riotto (2011) conjectured the equivalence of these systems in the special case where vector perturbations were neglected. We show that this approach does not lead to the Euler equation but to a physically different one with large deviations already in the 1-loop power spectrum. We show that it is also possible to consistently set to zero the vector perturbations which strongly constrains the allowed initial conditions, in particular excluding Gaussian ones such that inclusion of vector perturbations is inevitable in the cosmological context. In addition we derive nonlinear equations for the gravitational slip and tensor perturbations, thereby extending Newtonian gravity of a dust fluid to account for nonlinear light propagation effects and dust-induced gravitational waves.

  7. Toxicity evaluation and hazard review Cold Smoke

    SciTech Connect (OSTI)

    Archuleta, M.M.; Stocum, W.E.

    1993-12-01

    Cold Smoke is a dense white smoke produced by the reaction of titanium tetrachloride and aqueous ammonia aerosols. Early studies on the toxicity of this nonpyrotechnically generated smoke indicated that the smoke itself is essentially non-toxic (i.e. exhibits to systemic toxicity or organ damage due to exposure) under normal deployment conditions. The purpose of this evaluation was to review and summarize the recent literature data available on the toxicity of Cold Smoke, its chemical constituents, and its starting materials.

  8. development StemcellsSmokingFlu

    E-Print Network [OSTI]

    Crowther, Paul

    and cancer 1957 British Medical Council announces a "direct causal connection" between smoking and lung such as the `Gremlins' TV campaign 1999 Sure Start Programme for pre-school children influenced by RCUK research showing

  9. Dust cluster explosion

    SciTech Connect (OSTI)

    Saxena, Vikrant [School of Mathematics and Physics, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Institute for Plasma Research, Bhat, Gandhinagar (India); Avinash, K. [Department of Physics and Astrophysics, University of Delhi, New Delhi (India); Sen, A. [Institute for Plasma Research, Bhat, Gandhinagar (India)

    2012-09-15

    A model for the dust cluster explosion where micron/sub-micron sized particles are accelerated at the expense of plasma thermal energy, in the afterglow phase of a complex plasma discharge is proposed. The model is tested by molecular dynamics simulations of dust particles in a confining potential. The nature of the explosion (caused by switching off the discharge) and the concomitant dust acceleration is found to depend critically on the pressure of the background neutral gas. At low gas pressure, the explosion is due to unshielded Coulomb repulsion between dust particles and yields maximum acceleration, while in the high pressure regime it is due to shielded Yukawa repulsion and yields much feebler acceleration. These results are in agreement with experimental findings. Our simulations also confirm a recently proposed electrostatic (ES) isothermal scaling relation, P{sub E}{proportional_to}V{sub d}{sup -2} (where P{sub E} is the ES pressure of the dust particles and V{sub d} is the confining volume).

  10. Study reveals urban smoke absorbs sunlight, exacerbating climate...

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

    urban smoke absorbs sunlight Study reveals urban smoke absorbs sunlight, exacerbating climate warming Cloaking urban areas and wildfire zones, tiny smoke particles suspended in...

  11. Gravity's smoking gun?

    E-Print Network [OSTI]

    E. Gaztanaga; R. Juszkiewicz

    2001-08-21

    We present a new constraint on the biased galaxy formation picture. Gravitational instability theory predicts that the two-point mass density correlation function, \\xi(r), has an inflection point at the separation r=r_0, corresponding to the boundary between the linear and nonlinear regime of clustering, \\xi = 1. We show how this feature can be used to constrain the square of the biasing parameter, b^2 = \\xi_g / \\xi on scales r = r_0, where \\xi_g is the galaxy-galaxy correlation function, allowed to differ from \\xi. We apply our method to real data: the \\xi_g(r), estimated from the APM galaxy survey. Our results suggest that the APM galaxies trace the mass at separations r > 5 Mpc/h, where h is the Hubble constant in units of 100 km/s Mpc. The present results agree with earlier studies, based on comparing higher order correlations in the APM with weakly non-linear perturbation theory. Both approaches constrain the "b" factor to be within 20% of unity. If the existence of the feature we identified in the APM \\xi_g(r) -- the inflection point near \\xi_g = 1 -- is confirmed by more accurate surveys, we may have discovered gravity's smoking gun: the long awaited ``shoulder'' in \\xi, predicted by Gott and Rees 25 years ago.

  12. TWO INTERSTELLAR DUST CANDIDATES FROM THE STARDUST AEROGEL INTERSTELLAR DUST

    E-Print Network [OSTI]

    Nittler, Larry R.

    TWO INTERSTELLAR DUST CANDIDATES FROM THE STARDUST AEROGEL INTERSTELLAR DUST COLLECTOR A. J, and is expected to have collected several dozen contemporary interstellar dust particles in aerogel and aluminum@home, we have so far identified 28 tracks in the aerogel collectors. We report on the results

  13. Cotton Gin Dust Explosibility Determinations 

    E-Print Network [OSTI]

    Vanderlick, Francis Jerome

    2014-01-06

    the dust for explosibility based on the American Society for Testing and Materials (ASTM) E 1226 to ensure proper regulation of facilities. Dusts found in cotton gins were tested to determine if they are explosible. Safety Consulting Engineers Inc. (SCE...

  14. Dark Matter Velocity Spectroscopy

    E-Print Network [OSTI]

    Eric G. Speckhard; Kenny C. Y. Ng; John F. Beacom; Ranjan Laha

    2015-07-31

    Dark matter decays or annihilations that produce line-like spectra may be smoking-gun signals. However, even such distinctive signatures can be mimicked by astrophysical or instrumental causes. We show that velocity spectroscopy-the measurement of energy shifts induced by relative motion of source and observer-can separate these three causes with minimal theoretical uncertainties. The principal obstacle has been energy resolution, but upcoming experiments will reach the required 0.1% level. As an example, we show that the imminent Astro-H mission can use Milky Way observations to separate possible causes of the 3.5-keV line. We discuss other applications.

  15. Smoking Fish at Home--Safely

    E-Print Network [OSTI]

    Tullos, Desiree

    PNW238 Smoking Fish at Home--Safely A PACIFIC NORTHWEST EXTENSION PUBLICATION WASHINGTON STATE UNIVERSITY · OREGON STATE UNIVERSITY · UNIVERSITY OF IDAHO Three common factors in all hot fish-smok- ing-smoked fish safely. It also recom- mends refrigerated storage for all smoked fish. Note that the process

  16. 6, 32273264, 2006 Forest fire smoke

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 6, 3227­3264, 2006 Forest fire smoke plume V. R. Kotamarthi et al. Title Page Abstract Discussions Modeling of trace gases from the 1998 North Central Mexico forest fire smoke plume, as measured Forest fire smoke plume V. R. Kotamarthi et al. Title Page Abstract Introduction Conclusions References

  17. Centre for Smoking Cessation and Training

    E-Print Network [OSTI]

    Saunders, Mark

    Centre for Smoking Cessation and Training The NHS Centre for Smoking Cessation and Training (NCSCT and commissioners commission and provide training and continuing support to allow staff to achieve the required of training courses advise the Department of Health on issues relating to the Stop Smoking Services

  18. Trapping of dust and dust acoustic waves in laboratory plasmas

    SciTech Connect (OSTI)

    Prabhakara, H.R.; Tanna, V.L. [Institute for Plasma Research, Bhat, Gandhinagar 382 424 (India)] [Institute for Plasma Research, Bhat, Gandhinagar 382 424 (India)

    1996-08-01

    Trapping of negatively charged dust particles is observed in a hot cathode plasma discharge when a layer of dust is exposed to the plasma. The particles are visible in the scattered He{endash}Ne laser light. The trajectories of individual particles have been photographed. The dust particles are excluded from the sheath region of any object in the plasma. The intensity of scattered light as well as the potential on a floating Langmuir probe show coherent fluctuations in the frequency range 1{endash}15 Hz. After several hours of exposure to the plasma, the dust layer develops striations similar to those on sand dunes. Trapping of dust particles by the plasma and the possible identification of the observed low-frequency fluctuations with dust acoustic waves are discussed. {copyright} {ital 1996 American Institute of Physics.}

  19. 6, 96559722, 2006 Arctic smoke

    E-Print Network [OSTI]

    Boyer, Edmond

    Discussions Arctic smoke ­ record high air pollution levels in the European Arctic due to agricultural fires into the European Arctic and caused the most severe air pollution episodes ever recorded there. This paper confirms that biomass burning (BB) was in-5 deed the source of the observed air pollution, studies the transport

  20. Low temperature pyrotechnic smokes: A potential low cost alternative to nonpyrotechnic smoke for access delay applications

    SciTech Connect (OSTI)

    Greenholt, C.J.

    1995-07-01

    Smokes are frequently used as visual obscurants in access delay applications. A new generation of low temperature pyrotechnic smokes is being developed. Terephthalic Acid (TPA) smoke was developed by the U.S. Army and Sebacic Acid (SA) smoke is being developed by Thiokol Corp. The advantages these smokes offer over traditional pyrotechnic smokes include; low generation temperature (approximately 450{degree}C), lower toxicity, and lower corrosivity. The low generation temperature reduces smoke layering effects and allows the addition of sensory irritants, such as o-Chlorobenzylidene Malononitrile (CS), to the formulation. Some advantages low temperature pyrotechnic smokes offer over nonpyrotechnic smokes include; low cost, simplicity, compactness, light weight, long storage life, and orientation insensitive operation. Low cost permits distribution of multiple units for reduced vulnerability and refill flexibility. Some disadvantages may include the combustibility of the smoke particulate; however, the published lower explosive limit of the mentioned materials is approximately ten times greater than the concentration required for effective obscuration. The TPA smoke cloud contains small quantities of benzene, formaldehyde, and carbon monoxide; no benzene or formaldehyde was identified during preliminary SA smoke analyses performed by Thiokol Corp. Sandia performed tests and analyses on TPA smoke to determine the smoke cloud composition, the quantity of particulate produced per canister, and the relationship between airborne particulate concentration and measured optical density values. Current activities include characterization of SA smoke.

  1. Hazards of explosives dusts: Particle size effects

    SciTech Connect (OSTI)

    Cashdollar, K L; Hertzberg, M; Green, G M

    1992-02-01

    At the request of the Department of Energy, the Bureau of Mines has investigated the hazards of military explosives dispersed as dust clouds in a 20-L test chamber. In this report, the effect of particle size for HMX, HNS, RDX, TATB, and TNT explosives dusts is studied in detail. The explosibility data for these dusts are also compared to those for pure fuel dusts. The data show that all of the sizes of the explosives dusts that were studied were capable of sustaining explosions as dust clouds dispersed in air. The finest sizes (<10 [mu]m) of explosives dusts were less reactive than the intermediate sizes (20 to 60 [mu]m); this is opposite to the particle size effect observed previously for the pure fuel dusts. At the largest sizes studied, the explosives dusts become somewhat less reactive as dispersed dust clouds. The six sizes of the HMX dust were also studied as dust clouds dispersed in nitrogen.

  2. Characterization of secondary grain dust explosions 

    E-Print Network [OSTI]

    Schulman, Cheryl Wendler

    1983-01-01

    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...

  3. Dust Static Spherically Symmetric Solution in $f(R)$ Gravity

    E-Print Network [OSTI]

    Muhammad Sharif; Hafiza Rizwana Kausar

    2011-02-21

    In this paper, we take dust matter and investigate static spherically symmetric solution of the field equations in metric f(R) gravity. The solution is found with constant Ricci scalar curvature and its energy distribution is evaluated by using Landau-Lifshitz energy-momentum complex. We also discuss the stability condition and constant scalar curvature condition for some specific popular choices of f(R) models in addition to their energy distribution.

  4. New technology suppresses coke dust

    SciTech Connect (OSTI)

    Not Available

    1983-09-01

    A brief account is given of the technique of electrostatic fogging which has been tested successfully at a Canadian steel mill to control coke dust in the respirable size range. A spray of very fine droplets (<10 MUm) has an electrostatic charge imparted to each droplet. The spray of electrostatically-charged fog suppresses the dust by a combination of scrubbing and electrostatic attraction.

  5. Policy on Smoke-Free Campus Policy on Smoke-Free Campus

    E-Print Network [OSTI]

    Sridhar, Srinivas

    Policy on Smoke-Free Campus 7/16/2013 Policy on Smoke-Free Campus I. Policy Smoking of any tobacco-free campus policy. Having received the committee's recommendation, after extensive input from the community-free workplace. This policy applies to all persons, including all students, faculty, staff, volunteers, vendors

  6. Tobacco use in shisha: studies on waterpipe smoking in Egypt

    E-Print Network [OSTI]

    World Health Organization

    2006-01-01

    on waterpipe smoking in Egypt / WHO Regional Of?ce for theHealth surveys 5. Smoking – Egypt I. Title II Regional Of?ceshisha) smoking in cafés in Egypt. Journal of the Egyptian

  7. Canadian Expert Panel on Tobacco Smoke and Breast Cancer Risk

    E-Print Network [OSTI]

    2009-01-01

    1996. Cigarette smoking and breast cancer. Cancer Epidemiol.Cigarette smoking and breast cancer. BMJ 310, 1431-1433.smoking, and the risk of breast cancer. Cancer Detect. Prev.

  8. Observations of dust acoustic waves driven at high frequencies: Finite dust temperature effects and wave interference

    E-Print Network [OSTI]

    Merlino, Robert L.

    Observations of dust acoustic waves driven at high frequencies: Finite dust temperature effects An experiment has been performed to study the behavior of dust acoustic waves driven at high frequencies f 100 are observed--interference effects between naturally excited dust acoustic waves and driven dust acoustic waves

  9. Measurements of Smoke Characteristics in HVAC Ducts 

    E-Print Network [OSTI]

    Wolin, Steven D; Ryder, Noah L; Leprince, Frederic; Milke, James; Mowrer, Frederick; Torero, Jose L

    2001-01-01

    The characteristics of smoke traveling in an HVAC duct have been observed along with the response of selected duct smoke detectors. The simulated HVAC system consists of a 9 m long duct, 0.45 m in diameter. An exhaust fan is placed at one end...

  10. The genotoxic contribution of wood smoke to indoor respirable suspended particles

    SciTech Connect (OSTI)

    Boone, P.M. (John B. Pierce Foundation Laboratory, New Haven, CT (USA)); Rossman, T.G. (New York Univ. Medical Center, New York (USA)); Daisey, J.M. (Lawrence Berkeley Laboratory, CA (USA))

    1989-01-01

    The effect of wood burning stoves on the genotoxicity of indoor respirable organic matter was investigated for four homes during the winter and spring of 1986. Paired samples, one collected when the stove was not used and one when wood was burned, were extracted with dichloromethane and acetone. Aliquots of the dichloromethane extracts were analyzed with and without metabolic activation using the Microscreen bioassay. The Microscreen is a rapid, sensitive bioassay which measures a broad genotoxic endpoint, {lambda}-prophage induction. Per nanogram of organic material, wood smoke proved to be a major source of indirect (observed with metabolic activation) but not direct genotoxins in homes. The increase in indirect genotoxicity for extracts from aerosol containing wood smoke is probably due to higher concentrations of polycyclic aromatic hydrocarbons in the wood smoke aerosol as well as other unidentified classes. The direct genotoxicity observed for extracts of aerosol not containing wood smoke decreased with metabolic activation. This direct genotoxicity may be related to cooking activities in the homes. The trends in genotoxicity observed per nanogram of organic material are more pronounced when expressed per m{sup 3} of air due to the higher percentage of extractable material in aerosol containing wood smoke.

  11. Uranium mill ore dust characterization

    SciTech Connect (OSTI)

    Knuth, R.H.; George, A.C.

    1980-11-01

    Cascade impactor and general air ore dust measurements were taken in a uranium processing mill in order to characterize the airborne activity, the degree of equilibrium, the particle size distribution and the respirable fraction for the /sup 238/U chain nuclides. The sampling locations were selected to limit the possibility of cross contamination by airborne dusts originating in different process areas of the mill. The reliability of the modified impactor and measurement techniques was ascertained by duplicate sampling. The results reveal no significant deviation from secular equilibrium in both airborne and bulk ore samples for the /sup 234/U and /sup 230/Th nuclides. In total airborne dust measurements, the /sup 226/Ra and /sup 210/Pb nuclides were found to be depleted by 20 and 25%, respectively. Bulk ore samples showed depletions of 10% for the /sup 226/Ra and /sup 210/Pb nuclides. Impactor samples show disequilibrium of /sup 226/Ra as high as +-50% for different size fractions. In these samples the /sup 226/Ra ratio was generally found to increase as particle size decreased. Activity median aerodynamic diameters of the airborne dusts ranged from 5 to 30 ..mu..m with a median diameter of 11 ..mu..m. The maximum respirable fraction for the ore dusts, based on the proposed International Commission on Radiological Protection's (ICRP) definition of pulmonary deposition, was < 15% of the total airborne concentration. Ore dust parameters calculated for impactor duplicate samples were found to be in excellent agreement.

  12. Accepted Manuscript Dust in the planetary system: Dust interactions in space plasmas of the

    E-Print Network [OSTI]

    Aulanier, Guillaume

    Space Research Center, Polish Academy of Sciences, Warsaw, Poland Abstract Cosmic dust particles in cosmic dust particles. Some cosmic dust particles initially form by condensation of the heavy elements, colli- sional fragmentation, sputtering and particles are formed by agglomeration, condensation

  13. The dust and gas content of the Crab Nebula

    E-Print Network [OSTI]

    Owen, P J

    2015-01-01

    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...

  14. Understanding the 30-year Barbados desert dust record

    E-Print Network [OSTI]

    Mahowald, Natalie M; Zender, C. S.; Luo, C.; Savoie, D.; Torres, O.; del Corral, J.

    2002-01-01

    UNDERSTANDING THE 30-YEAR BARBADOS DESERT DUST Moulin, C. ,on mineral dust in the Barbados trade winds, Nature, 320,Understanding the 30-year Barbados desert dust record, J.

  15. The Smoke Control Area (Authorised Fuels) Regulations 1963 

    E-Print Network [OSTI]

    Joseph, Keith

    1963-01-01

    STATUTORY INSTRUMENTS 1963 No. 1275 CLEAN AIR The Smoke Control Areas (Authorised Fuels) Regulations 1963

  16. Unified Description of Dark Energy and Dark Matter

    E-Print Network [OSTI]

    Walter Petry

    2008-11-09

    Dark energy in the universe is assumed to be vacuum energy. The energy-momentum of vacuum is described by a scale-dependent cosmological constant. The equations of motion imply for the density of matter (dust) the sum of the usual matter density (luminous matter) and an additional matter density (dark matter) similar to the dark energy. The scale-dependent cosmological constant is given up to an exponent which is approximated by the experimentally decided density parameters of dark matter and dark energy. This yields that dark matter is one third of dark energy for all times implying an explanation of the coincidence of dark matter and dark energy. In the final state, the universe becomes dark, consisting of dark matter and dark energy.

  17. Glass Frit Clumping And Dusting

    SciTech Connect (OSTI)

    Steimke, J. L.

    2013-09-26

    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

  18. Aeolian Delivery of Organic Matter to a Middle Permian Deepwater Ramp 

    E-Print Network [OSTI]

    Artan, Sinem

    2012-07-16

    of the Brushy Canyon Formation sandstones and siltstones to evaluate the significance of windblown dust in delivery of sediment and terrestrial organic matter to the Middle Permian Delaware Basin. Ramp siltstones of the basin have been interpreted...

  19. Towards graphene-based detectors for dark matter directional detection

    E-Print Network [OSTI]

    Wang, Shang-Yung

    2015-01-01

    Dark matter detectors with directional sensitivity have the capability to distinguish dark matter induced nuclear recoils from isotropic backgrounds, thus providing a smoking gun signature for dark matter in the Galactic halo. Here we propose a conceptually novel class of high directional sensitivity dark matter detectors utilizing graphene-based van der Waals heterostructures. The advantages over conventional low pressure gas time projection chamber-based directional detectors are discussed in detail. A practical implementation using graphene/hexagonal boron nitride and graphene/molybdenum disulfide heterostructures is presented together with an overwhelming amount of experimental evidence in strong support of its feasibility.

  20. Secondary dust density waves excited by nonlinear dust acoustic waves J. R. Heinrich,1,a)

    E-Print Network [OSTI]

    Merlino, Robert L.

    Secondary dust density waves excited by nonlinear dust acoustic waves J. R. Heinrich,1,a) S.-H. Kim amplitude ðnd=nd0 > 2Þ dust acoustic waves (DAW) that were spontaneously excited in a dc glow discharge dusty plasma in the moderately coupled, C $ 1; state. The high amplitude dust acoustic waves produced

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

    E-Print Network [OSTI]

    Barkan, Christopher P.L.

    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

  2. Adding coal dust to coal batch

    SciTech Connect (OSTI)

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

    2009-05-15

    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.

  3. 205:20130828.1126 Dust Accelerator Laboratory

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    205:20130828.1126 Dust Accelerator Laboratory Through the Dust Accelerator Laboratory, LASP, and laboratory experiments. Our goal is to address basic physical and applied exploration questions, including Laboratory is home to world-class facilities, including the largest dust accelerator in the world

  4. Active, but not passive cigarette smoking was inversely associated with mammographic density

    E-Print Network [OSTI]

    2010-01-01

    ORIGINAL PAPER Active, but not passive cigarette smoking wasAccumulating evidence on passive and active smoking andA (2002) Smoking (active and passive) and breast cancer:

  5. Expanded solid matter: Two-dimensional LJ modeling F.H. Stillinger *, D.K. Stillinger

    E-Print Network [OSTI]

    Stillinger, Frank

    and technological importance of expanded solid forms of matter such as aerogels indicate the need for related. Keywords: Aerogels; Lennard-Jones model; Inherent structures; Fractal clusters; Burgers vector solid matter is provided by the family of silica-based aerogels (``solid smoke'') that can have mass

  6. as smoking and exposure to secondhand smoke outside the home were more prevalent in New Zealand

    E-Print Network [OSTI]

    in the early 1980s. This may explain the apparently stronger association between household exposure to the weight of evi- dence of harm caused by passive smoking and support steps to reduce exposure to other Health 1989;79:163-7. 2 Svendsen K, Kuller L, Martin M, Ockene J. Effects of passive smoking

  7. Dark Matters

    ScienceCinema (OSTI)

    Joseph Silk

    2010-01-08

    One of the greatest mysteries in the cosmos is that it is mostly dark.  Astronomers and particle physicists today are seeking to unravel the nature of this mysterious, but pervasive dark matter which has profoundly influenced the formation of structure in the universe.  I will describe the complex interplay between galaxy formation and dark matter detectability and review recent attempts to measure particle dark matter by direct and indirect means.

  8. Smoking in top-grossing US movies 2014

    E-Print Network [OSTI]

    Polansky, Jonathan R; Titus, Kori; Atayeva, Renata; Glantz, Stanton A PhD

    2015-01-01

    Smoking in top?grossing US movies Jonathan R. PolanskyApril 23, 2015 Smoking in top?grossing US movies: 2014 | 2about 20 percent of all top?grossing films. Tobacco presence

  9. Evolution of Gas and Dust in Circumstellar Disks

    E-Print Network [OSTI]

    David W. Koerner

    1999-12-17

    A clear understanding of the chemical processing of matter, as it is transferred from a molecular cloud to a planetary system, depends heavily on knowledge of the physical conditions endured by gas and dust as these accrete onto a disk and are incorporated into planetary bodies. Reviewed here are astrophysical observations of circumstellar disks which trace their evolving properties. Accretion disks that are massive enough to produce a solar system like our own are typically larger than 100 AU. This suggests that the chemistry of a large fraction of the infalling material is not radically altered upon contact with a vigorous accretion shock. The mechanisms of accretion onto the star and eventual dispersal are not yet well understood, but timescales for the removal of gas and optically thick dust appear to be a few times 10$^6$ yrs. At later times, tenuous ``debris disks'' of dust remain around stars as old as a few times 10$^8$ yrs. Features in the morphology of the latter, such as inner holes, warps, and azimuthal asymmetries, are likely to be the result of the dynamical influence of large planetary bodies. Future observations will enlighten our understanding of chemical evolution and will focus on the search for disks in transition from a viscous accretion stage to one represented by a gas-free assemblage of colliding planetesimals. In the near future, comparative analysis of circumstellar dust and gas properties within a statistically significant sample of young stars at various ages will be possible with instrumentation such as SIRTF and SOFIA. Well-designed surveys will help place solar system analogs in a general context of a diversity of possible pathways for circumstellar evolution, one which encompasses the formation of stellar and brown-dwarf companions as well as planetary systems.

  10. A multicomponent smoking cessation program for couples 

    E-Print Network [OSTI]

    Nottingham, Carolyn Robin

    1987-01-01

    with rather "hard-core" smokers. The p('og('am included twenty-two men between the ages of 42 and 61. The subjects were at high risk for coronary heart disease, had smoked for about 33 years, and consumed approximately 33 cigarettes per day. The main... the number of cigarettes smoked. As was demonstrated in the study conducted by Powell and Arnold ( 1982), multicomponent programs can result in high percentages of abstinence rates for even rather "hard-core' smokers. The author was guided...

  11. Dusty supernovae running the thermodynamics of the matter reinserted within young and massive super stellar clusters

    SciTech Connect (OSTI)

    Tenorio-Tagle, Guillermo; Silich, Sergiy; Martínez-González, Sergio [Instituto Nacional de Astrofísica Óptica y Electrónica, AP 51, 72000 Puebla (Mexico); Muñoz-Tuñón, Casiana [Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife (Spain); Palouš, Jan; Wünsch, Richard, E-mail: gtt@inaoep.mx, E-mail: cmt@ll.iac.es [Astronomical Institute, Academy of Sciences of the Czech Republic, Bo?ní II 1401, 141 31 Prague (Czech Republic)

    2013-12-01

    Following the observational and theoretical evidence that points at core-collapse supernovae (SNe) as major producers of dust, here we calculate the hydrodynamics of the matter reinserted within young and massive super stellar clusters under the assumption of gas and dust radiative cooling. The large SN rate expected in massive clusters allows for a continuous replenishment of dust immersed in the high temperature thermalized reinserted matter and warrants a stationary presence of dust within the cluster volume during the type II SN era. We first show that such a balance determines the range of the dust-to-gas-mass ratio, and thus the dust cooling law. We then search for the critical line that separates stationary cluster winds from the bimodal cases in the cluster mechanical luminosity (or cluster mass) versus cluster size parameter space. In the latter, strong radiative cooling reduces considerably the cluster wind mechanical energy output and affects particularly the cluster central regions, leading to frequent thermal instabilities that diminish the pressure and inhibit the exit of the reinserted matter. Instead, matter accumulates there and is expected to eventually lead to gravitational instabilities and to further stellar formation with the matter reinserted by former massive stars. The main outcome of the calculations is that the critical line is almost two orders of magnitude or more, depending on the assumed value of V {sub A?}, lower than when only gas radiative cooling is applied. And thus, many massive clusters are predicted to enter the bimodal regime.

  12. Twelve thousand years of dust: the Holocene global dust cycle constrained by natural archives

    E-Print Network [OSTI]

    Albani, S.

    Mineral dust plays an important role in the climate system by interacting with radiation, clouds, and biogeochemical cycles. In addition, natural archives show that the dust cycle experienced variability in the past in ...

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

    E-Print Network [OSTI]

    Newman, David

    Mineral Dust Entrainment and Deposition (DEAD) model: Description and 1990s dust climatology to 1999 is simulated with our mineral aerosol entrainment and deposition module embedded in a chemical transport model. Mobilization processes include entrainment thresholds for saltation, moisture inhibition

  14. Filament-Based Smoke vorgelegt von

    E-Print Network [OSTI]

    Weissmann, Steffen

    Filament-Based Smoke vorgelegt von Diplom-Mathematiker Steffen Weißmann Neuburg an der Donau Von filaments. Based on a Hamiltonian system for the dynamics of smooth vortex filaments, we develop to use coarse polygonal vortex filaments, while preserving the qualitative behavior of the smooth system

  15. Dust Defeats Germ-Killing Fabrics | Jefferson Lab

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

    Kelley speculates that dust protected germs from the fabrics' germ-killing surface. "Microbes grow on the dust. And now, because you have all this dust on the fabric, instead of...

  16. Rigidly rotating cylinders of charged dust

    E-Print Network [OSTI]

    B. V. Ivanov

    2002-07-02

    The gravitational field of a rigidly rotating cylinder of charged dust is found analytically. The general and all regular solutions are divided into three classes. The acceleration and the vorticity of the dust are given, as well as the conditions for the appearance of closed timelike curves.

  17. Global dust model intercomparison in AeroCom phase I

    E-Print Network [OSTI]

    2011-01-01

    Atlantic as recorded in both Barbados surface concentrationsmarine boundary layer at Barbados: Impact of African dust,on Mineral Dust in the Barbados Trade Winds, Nature, 320(

  18. Dust Emission from the Perseus Molecular Cloud

    E-Print Network [OSTI]

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

    2008-05-27

    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.

  19. Cigarette, cigar and pipe smoking, passive smoke exposure, and risk of pancreatic cancer: a population-based study in the San Francisco Bay Area

    E-Print Network [OSTI]

    Tranah, Gregory J; Holly, Elizabeth A; Wang, Furong; Bracci, Paige M

    2011-01-01

    cigarette smoking, household passive smoke exposure, and theb 1.0 (Ref. ) Passive exposure to household and workplaceIn this study, passive exposure to household and workplace

  20. Quitting smoking and experience of smoking cessation interventions among UK Bangladeshi and Pakistani adults: the views of community members and health professionals 

    E-Print Network [OSTI]

    Bhopal, Raj; White, Martin; Bush, Judith; Kai, Joe; Rankin, Judith

    2006-05-01

    Objective: To explore attitudes to quitting smoking and experience of smoking cessation among Bangladeshi and Pakistani ethnic minority communities. Design: Qualitative study using community participatory methods, purposeful ...

  1. Indoor Measurements of Environmental Tobacco Smoke Final Report to the Tobacco Related Disease Research Program

    SciTech Connect (OSTI)

    Apte, Michael G.; Gundel, Lara A.; Dod, Raymond L.; Russell, Marion L.; Singer, Brett C.; Sohn, Michael D.; Sullivan, Douglas P.; Chang, Gee-Minn; Sextro, Richard G.

    2004-03-02

    The objective of this research project was to improve the basis for estimating environmental tobacco smoke (ETS) exposures in a variety of indoor environments. The research utilized experiments conducted in both laboratory and ''real-world'' buildings to (1) study the transport of ETS species from room to room, (2) examine the viability of using various chemical markers as tracers for ETS, and (3) to evaluate to what extent re-emission of ETS components from indoor surfaces might add to the ETS exposure estimates. A three-room environmental chamber was used to examine multi-zone transport and behavior of ETS and its tracers. One room (simulating a smoker's living room) was extensively conditioned with ETS, while a corridor and a second room (simulating a child's bedroom) remained smoking-free. A series of 5 sets of replicate experiments were conducted under different door opening and flow configurations: sealed, leaky, slightly ajar, wide open, and under forced air-flow conditions. When the doors between the rooms were slightly ajar the particles dispersed into the other rooms, eventually reaching the same concentration. The particle size distribution took the same form in each room, although the total numbers of particles in each room depended on the door configurations. The particle number size distribution moved towards somewhat larger particles as the ETS aged. We also successfully modeled the inter-room transport of ETS particles from first principles--using size fractionated particle emission factors, predicted deposition rates, and thermal temperature gradient driven inter-room flows, This validation improved our understanding of bulk inter-room ETS particle transport. Four chemical tracers were examined: ultraviolet-absorbing particulate matter (UVPM), fluorescent particulate matter (FPM), nicotine and solanesol. Both (UVPM) and (FPM) traced the transport of ETS particles into the non-smoking areas. Nicotine, on the other hand, quickly adsorbed on unconditioned surfaces so that nicotine concentrations in these rooms remained very low, even during smoking episodes. These findings suggest that using nicotine as a tracer of ETS particle concentrations may yield misleading concentration and/or exposure estimates. The results of the solanesol analyses were compromised, apparently by exposure to light during collection (lights in the chambers were always on during the experiments). This may mean that the use of solanesol as a tracer is impractical in ''real-world'' conditions. In the final phase of the project we conducted measurements of ETS particles and tracers in three residences occupied by smokers who had joined a smoking cessation program. As a pilot study, its objective was to improve our understanding of how ETS aerosols are transported in a small number of homes (and thus, whether limiting smoking to certain areas has an effect on ETS exposures in other parts of the building). As with the chamber studies, we examined whether measurements of various chemical tracers, such as nicotine, solanesol, FPM and UVPM, could be used to accurately predict ETS concentrations and potential exposures in ''real-world'' settings, as has been suggested by several authors. The ultimate goal of these efforts, and a future larger multiple house study, is to improve the basis for estimating ETS exposures to the general public. Because we only studied three houses no firm conclusions can be developed from our data. However, the results for the ETS tracers are essentially the same as those for the chamber experiments. The use of nicotine was problematic as a marker for ETS exposure. In the smoking areas of the homes, nicotine appeared to be a suitable indicator; however in the non-smoking regions, nicotine behavior was very inconsistent. The other tracers, UVPM and FPM, provided a better basis for estimating ETS exposures in the ''real world''. The use of solanesol was compromised--as it had been in the chamber experiments.

  2. Cascading dust inflation in Born-Infeld gravity

    E-Print Network [OSTI]

    Jose Beltran Jimenez; Lavinia Heisenberg; Gonzalo J. Olmo; Christophe Ringeval

    2015-09-04

    In the framework of Born-Infeld inspired gravity theories, which deviates from General Relativity (GR) in the high curvature regime, we discuss the viability of Cosmic Inflation without scalar fields. For energy densities higher than the new mass scale of the theory, a gravitating dust component is shown to generically induce an accelerated expansion of the Universe. Within such a simple scenario, inflation gracefully exits when the GR regime is recovered, but the Universe would remain matter dominated. In order to implement a reheating era after inflation, we then consider inflation to be driven by a mixture of unstable dust species decaying into radiation. Because the speed of sound gravitates within the Born-Infeld model under consideration, our scenario ends up being predictive on various open questions of the inflationary paradigm. The total number of e-folds of acceleration is given by the lifetime of the unstable dust components and is related to the duration of reheating. As a result, inflation does not last much longer than the number of e-folds of deceleration allowing a small spatial curvature and large scale deviations to isotropy to be observable today. Energy densities are self-regulated as inflation can only start for a total energy density less than a threshold value, again related to the species' lifetime. Above this threshold, the Universe may bounce thereby avoiding a singularity. Another distinctive feature is that the accelerated expansion is of the superinflationary kind, namely the first Hubble flow function is negative. We show however that the tensor modes are never excited and the tensor-to-scalar ratio is always vanishing, independently of the energy scale of inflation.

  3. Anticipating Patentable Subject Matter

    E-Print Network [OSTI]

    Burk, DL

    2015-01-01

    February 2013] PATENTABLE SUBJECT MATTER patentability—imports into patent law’s subject matter provisions theunder either novelty or subject matter. The proper question

  4. 2-ethylpyridine, a cigarette smoke component, causes mitochondrial damage in human retinal pigment epithelial cells in vitro

    E-Print Network [OSTI]

    Kenney, MC; Mansoor, S; Gupta, N; Falatoonzadeh, P; Kuppermann, BD

    2014-01-01

    a cigarette smoke component, causes mitochondrial damage ina cigarette smoke component, causes mitochondrial damage ina cigarette smoke component, causes mitochondrial damage in

  5. Tensile & shear strength of porous dust agglomerates

    E-Print Network [OSTI]

    Alexander Seizinger; Roland Speith; Wilhelm Kley

    2013-08-23

    Context.Within the sequential accretion scenario of planet formation, planets are build up through a sequence sticking collisions. The outcome of collisions between porous dust aggregates is very important for the growth from very small dust particles to planetesimals. In this work we determine the necessary material properties of dust aggregates as a function the porosity. Aims: Continuum models such as SPH that are capable of simulating collisions of macroscopic dust aggregates require a set of material parameters. Some of them such as the tensile and shear strength are ?difficult to obtain from laboratory experiments. The aim of this work is to determine these parameters from ab-initio molecular dynamics simulations. Methods: We simulate the behavior of porous dust aggregates using a detailed micro-physical model of the interaction of spherical grains that includes adhesion forces, rolling, twisting, and sliding. Using different methods of preparing the samples we study the strength behavior of our samples with varying porosity and coordination number of the material. Results: For the tensile strength, we can reproduce data from laboratory experiments very well. For the shear strength, there are no experimental data available. The results from our simulations differ significantly from previous theoretical models, which indicates that the latter might not be sufficient to describe porous dust aggregates. Conclusions: We have provided functional behavior of tensile and shear strength of porous dust aggregates as a function of the porosity that can be directly applied in continuum simulations of these objects in planet formation scenarios.

  6. Dust Combustion Safety Issues for Fusion Applications

    SciTech Connect (OSTI)

    L. C. Cadwallader

    2003-05-01

    This report summarizes the results of a safety research task to identify the safety issues and phenomenology of metallic dust fires and explosions that are postulated for fusion experiments. There are a variety of metal dusts that are created by plasma erosion and disruptions within the plasma chamber, as well as normal industrial dusts generated in the more conventional equipment in the balance of plant. For fusion, in-vessel dusts are generally mixtures of several elements; that is, the constituent elements in alloys and the variety of elements used for in-vessel materials. For example, in-vessel dust could be composed of beryllium from a first wall coating, tungsten from a divertor plate, copper from a plasma heating antenna or diagnostic, and perhaps some iron and chromium from the steel vessel wall or titanium and vanadium from the vessel wall. Each of these elements has its own unique combustion characteristics, and mixtures of elements must be evaluated for the mixture’s combustion properties. Issues of particle size, dust temperature, and presence of other combustible materials (i.e., deuterium and tritium) also affect combustion in air. Combustion in other gases has also been investigated to determine if there are safety concerns with “inert” atmospheres, such as nitrogen. Several coolants have also been reviewed to determine if coolant breach into the plasma chamber would enhance the combustion threat; for example, in-vessel steam from a water coolant breach will react with metal dust. The results of this review are presented here.

  7. Matter Field, Dark Matter and Dark Energy

    E-Print Network [OSTI]

    Masayasu Tsuge

    2009-03-24

    A model concerning particle theory and cosmology is proposed. Matter field, dark matter and dark energy are created by an energy flow from space to primordial matter fields at the phase transition in the early universe.

  8. Water Sampling At Valley Of Ten Thousand Smokes Region Area ...

    Open Energy Info (EERE)

    Water Sampling At Valley Of Ten Thousand Smokes Region Area (Keith, Et Al., 1992) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Water Sampling...

  9. Data Acquisition-Manipulation At Valley Of Ten Thousand Smokes...

    Open Energy Info (EERE)

    Data Acquisition-Manipulation At Valley Of Ten Thousand Smokes Region Area (Kodosky & Keith, 1993) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration...

  10. Dust-Acoustic Waves: Visible Sound Waves Robert L. Merlino

    E-Print Network [OSTI]

    Merlino, Robert L.

    Dust-Acoustic Waves: Visible Sound Waves Robert L. Merlino Department of Physics and Astronomy and experimental work on dust acoustic waves is given. The basic physics of the dust acoustic wave and some findings and outstanding problems are also presented. Keywords: dusty plasmas, dust acoustic waves PACS: 52

  11. The gas temperature in circumstellar disks: effects of dust settling

    E-Print Network [OSTI]

    Zadelhoff, Gerd-Jan van

    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

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

    E-Print Network [OSTI]

    Fang, Guangyang

    2012-07-16

    an important role in climate change, the majorities of aerosols are natural ones and can impact cloud properties, convective cloud dynamics, and the development of tropical storms (Jones et al. 2004). The optical properties of mineral dust aerosols... dusts from the Rayleigh regime to the geometric optics regime. A database of the optical properties of randomly oriented spheroids has been developed. 4.1 Geometry of the dust particle model The geometry of the spheroidal model used is shown...

  13. Surface acoustic wave dust deposition monitor

    DOE Patents [OSTI]

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

    1988-02-12

    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.

  14. Global coherence of dust density waves

    SciTech Connect (OSTI)

    Killer, Carsten; Melzer, André

    2014-06-15

    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.

  15. Transparent self-cleaning dust shield

    DOE Patents [OSTI]

    Mazumder, Malay K.; Sims, Robert A.; Wilson, James D.

    2005-06-28

    A transparent electromagnetic shield to protect solar panels and the like from dust deposition. The shield is a panel of clear non-conducting (dielectric) material with embedded parallel electrodes. The panel is coated with a semiconducting film. Desirably the electrodes are transparent. The electrodes are connected to a single-phase AC signal or to a multi-phase AC signal that produces a travelling electromagnetic wave. The electromagnetic field produced by the electrodes lifts dust particles away from the shield and repels charged particles. Deposited dust particles are removed when the electrodes are activated, regardless of the resistivity of the dust. Electrostatic charges on the panel are discharged by the semiconducting film. When used in conjunction with photovoltaic cells, the power for the device may be obtained from the cells themselves. For other surfaces, such as windshields, optical windows and the like, the power must be derived from an external source. One embodiment of the invention employs monitoring and detection devices to determine when the level of obscuration of the screen by dust has reached a threshold level requiring activation of the dust removal feature.

  16. HEAVY DUST OBSCURATION OF z = 7 GALAXIES IN A COSMOLOGICAL HYDRODYNAMIC SIMULATION

    SciTech Connect (OSTI)

    Kimm, Taysun; Cen, Renyue

    2013-10-10

    Hubble Space Telescope observations with the Wide Field Camera 3/Infrared reveal that galaxies at z ? 7 have very blue ultraviolet (UV) colors, consistent with these systems being dominated by young stellar populations with moderate or little attenuation by dust. We investigate UV and optical properties of the high-z galaxies in the standard cold dark matter model using a high-resolution adaptive mesh refinement cosmological hydrodynamic simulation. For this purpose, we perform panchromatic three-dimensional dust radiative transfer calculations on 198 galaxies of stellar mass 5 × 10{sup 8}-3 × 10{sup 10} M{sub ?} with three parameters: the dust-to-metal ratio, the extinction curve, and the fraction of directly escaped light from stars (f{sub esc}). Our stellar mass function is found to be in broad agreement with Gonzalez et al., independent of these parameters. We find that our heavily dust-attenuated galaxies (A{sub V} ? 1.8) can also reasonably match modest UV-optical colors, blue UV slopes, as well as UV luminosity functions, provided that a significant fraction (?10%) of light directly escapes from them. The observed UV slope and scatter are better explained with a Small-Magellanic-Cloud-type extinction curve, whereas a Milky-Way-type curve also predicts blue UV colors due to the 2175 Å bump. We expect that upcoming observations by the Atacama Large Millimeter/submillimeter Array will be able to test this heavily obscured model.

  17. Quantum gravitational dust collapse does not result in a black hole

    E-Print Network [OSTI]

    Cenalo Vaz

    2014-12-22

    Quantum gravity suggests that the paradox recently put forward by Almheiri et. al. (AMPS) can be resolved if matter does not undergo continuous collapse to a singularity but condenses on the apparent horizon. One can then expect a quasi-static object to form even after the gravitational field has overcome any degeneracy pressure of the matter fields. We consider dust collapse. If the collapse terminates on the apparent horizon, the Misner-Sharp mass function of the dust ball is predicted and we construct static solutions with no tangential pressure that would represent such a compact object. The collapse wave functions indicate that there will be processes by which energy extraction from the center occurs. These leave behind a negative point mass at the center which contributes to the total energy of the system but has no effect on the the energy density of the dust ball. The solutions describe a compact object whose boundary lies outside its Schwarzschild radius and which is hardly distinguishable from a neutron star.

  18. Computer tomography of large dust clouds in complex plasmas

    SciTech Connect (OSTI)

    Killer, Carsten; Himpel, Michael; Melzer, André

    2014-10-15

    The dust density is a central parameter of a dusty plasma. Here, a tomography setup for the determination of the three-dimensionally resolved density distribution of spatially extended dust clouds is presented. The dust clouds consist of micron-sized particles confined in a radio frequency argon plasma, where they fill almost the entire discharge volume. First, a line-of-sight integrated dust density is obtained from extinction measurements, where the incident light from an LED panel is scattered and absorbed by the dust. Performing these extinction measurements from many different angles allows the reconstruction of the 3D dust density distribution, analogous to a computer tomography in medical applications.

  19. Morphology and kinematics of HI in dust-lane elliptical galaxies

    E-Print Network [OSTI]

    Raffaella Morganti; Tom Oosterloo; Elaine Sadler; Daniela Vergani

    1998-09-07

    We present the results of the HI observations of four dust-lane ellipticals. The HI detected is regularly distributed in disks or rings. Moreover, in three of the four objects we have detected a very large amount of neutral hydrogen with values of M_HI/L_B that are at the end of the distribution characteristic of ellipticals and similar to what typically found in spiral galaxies. Thus, these dust-lane ellipticals may represent the results of major mergers as seen at a late stage of the evolution. The regular HI distribution and kinematics has allowed to derive values of M/L_B~20 at distances of ~5 R_e from the centre. Evidence for an increase of the dark matter contribution at larger radii can also be derived from the flat rotation curves observed in some of the observed galaxies.

  20. Matter Wave Radiation Leading to Matter Teleportation

    E-Print Network [OSTI]

    Yong-Yi Huang

    2015-02-12

    The concept of matter wave radiation is put forward, and its equation is established for the first time. The formalism solution shows that the probability density is a function of displacement and time. A free particle and a two-level system are reinvestigated considering the effect of matter wave radiation. Three feasible experimental designs, especially a modified Stern-Gerlach setup, are proposed to verify the existence of matter wave radiation. Matter wave radiation effect in relativity has been formulated in only a raw formulae, which offers another explanation of Lamb shift. A possible mechanics of matter teleportation is predicted due to the effect of matter wave radiation.

  1. Dust Studies in DIII-D and TEXTOR

    SciTech Connect (OSTI)

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

    2009-02-17

    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. 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. Direct heating of the dust particles by the neutral beam injection (NBI) and acceleration of dust particles by the plasma flows are observed. Energetic plasma disruptions produce significant amounts of dust. Large flakes or debris falling into the plasma may result in a disruption. Migration of pre-characterized carbon dust is studied in DIII-D and TEXTOR by introducing 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. 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. 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.

  2. Cold condensation of dust in the ISM

    E-Print Network [OSTI]

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

    2015-01-01

    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...

  3. Baryonic matter and beyond

    E-Print Network [OSTI]

    Kenji Fukushima

    2014-10-01

    We summarize recent developments in identifying the ground state of dense baryonic matter and beyond. The topics include deconfinement from baryonic matter to quark matter, a diquark mixture, topological effect coupled with chirality and density, and inhomogeneous chiral condensates.

  4. EFFECTS OF DUST FEEDBACK ON VORTICES IN PROTOPLANETARY DISKS

    SciTech Connect (OSTI)

    Fu, Wen; Liang, Edison; Li, Hui; Li, Shengtai; Lubow, Stephen

    2014-11-10

    We carried out two-dimensional, high-resolution simulations to study the effect of dust feedback on the evolution of vortices induced by massive planets in protoplanetary disks. Various initial dust to gas disk surface density ratios (0.001-0.01) and dust particle sizes (Stokes number 4 × 10{sup –4}-0.16) are considered. We found that while dust particles migrate inward, vortices are very effective at collecting them. When dust density becomes comparable to gas density within the vortex, a dynamical instability is excited and it alters the coherent vorticity pattern and destroys the vortex. This dust feedback effect is stronger with a higher initial dust/gas density ratio and larger dust grain. Consequently, we found that the disk vortex lifetime can be reduced up to a factor of 10. We discuss the implications of our findings on the survivability of vortices in protoplanetary disks and planet formation.

  5. Saharan dust particles nucleate droplets in eastern Atlantic clouds Cynthia H. Twohy,1

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    as CCN. Given the dual nature of Saharan dust particles as CCN and ice nuclei, this infusion of dust

  6. Dust studies in DIII-D and TEXTOR

    SciTech Connect (OSTI)

    Rudakov, D.L.; Litnovsky, A; West, W. P.; Yu, J.H.; Boedo, J.A.; McLean, Adam G

    2009-01-01

    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. Submicrometre 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. Heating of the dust particles by the neutral beam injection (NBI) and acceleration of dust particles by the plasma flows are observed. Energetic plasma disruptions produce significant amounts of dust; on the other hand, large flakes or debris falling into the plasma may induce a disruption. Migration of pre-characterized carbon dust is studied in DIII-D and TEXTOR by introducing micrometre-size particles into plasma discharges. In DIII-D, a sample holder filled with 30-40 mg of dust is inserted in the lower divertor and exposed, via sweeping of the strike points, to the diverted plasma flux of high-power ELMing H-mode discharges. After a brief dwell (similar to 0.1 s) of the outer strike point on the sample holder, part of the dust penetrates into the core plasma, raising the core carbon density by a factor of 2-3 and resulting in a twofold increase in the radiated power. 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 1.4 MW of NBI. Launched in this configuration, the dust perturbed the edge plasma, as evidenced by a moderate increase in the edge carbon content, but did not penetrate into the core plasma.

  7. Next Century Challenges: Mobile Networking for "Smart Dust"

    E-Print Network [OSTI]

    California at Berkeley, University of

    Next Century Challenges: Mobile Networking for "Smart Dust" J. M. Kahn, R. H. Katz (ACM Fellow), K into a complete system. We review the key elements of the emer- gent technology of "Smart Dust" and outline and communica- tion capabilities, and a power supply. Berkeley's Smart Dust project, led by Professors Pister

  8. varicose veins smoking obesity swine flu high blood pressure

    E-Print Network [OSTI]

    Rambaut, Andrew

    diabetes kidney failure dementia thrombosis high anorexia nervosa hormone replacement varicose veins underactive thyroid cystitis incontinence breast cancer obesity bulimia nervosa anorexia nervosa hormone obesity bulimia nervosa anorexia nervosa hormone replacement varicose veins smoking high blood pressure

  9. Transport of smoke from the Central American Fires of 1998 

    E-Print Network [OSTI]

    Rogers, Christopher Matthias

    2000-01-01

    During the spring of 1998, smoke produced by biomass burning in Central America was transported northward, where it eventually affected the United States. The Total Ozone Mapping Spectrometer (TOMS) aerosol index is used in this study to measure...

  10. Three-Dimensional Dust Radiative Transfer

    E-Print Network [OSTI]

    Baes, Maarten

    data using 3D dust RT codes. We end with an outlook on the bright future of this field. 63 Annu such as the Solar System (Hoppe et al. 2010), comets and meteoroids (K¨uppers et al. 2005), substellar atmospheres

  11. The general double-dust solution

    E-Print Network [OSTI]

    B. V. Ivanov

    2003-02-04

    The gravitational field of two identical rotating and counter-moving dust beams is found in full generality. The solution depends on an arbitrary function and a parameter. Some of its properties are studied. Previous particular solutions are derived as subcases.

  12. Harvard University recognizes that smoking is dangerous to the health of the smoker and that involuntary smoking is a cause of disease, including lung

    E-Print Network [OSTI]

    Mootha, Vamsi K.

    and that involuntary smoking is a cause of disease, including lung cancer, in healthy nonsmokers. The simple separation

  13. Hollow nuclear matter

    E-Print Network [OSTI]

    Gao-Chan Yong

    2015-12-18

    It is generally considered that an atomic nucleus is always compact. Based on the isospin-dependent Boltzmann nuclear transport model, here I show that large block nuclear matter or excited nuclear matter may both be hollow. And the size of inner bubble in these matter is affected by the charge number of nuclear matter. Existence of hollow nuclear matter may have many implications in nuclear or atomic physics or astrophysics as well as some practical applications.

  14. Hollow nuclear matter

    E-Print Network [OSTI]

    Yong, Gao-Chan

    2015-01-01

    It is generally considered that an atomic nucleus is always compact. Based on the isospin-dependent Boltzmann nuclear transport model, here I show that large block nuclear matter or excited nuclear matter may both be hollow. And the size of inner bubble in these matter is affected by the charge number of nuclear matter. Existence of hollow nuclear matter may have many implications in nuclear or atomic physics or astrophysics as well as some practical applications.

  15. Search for high-energy neutrinos from dust obscured Blazars

    E-Print Network [OSTI]

    Maggi, G; Correa, P; Vries, K D; Gentile, G; Scholten, O; van Eijndhoven, N

    2015-01-01

    The recent discovery of high-energy cosmic neutrinos by the IceCube neutrino observatory opens up a new field in physics, the field of neutrino astronomy. Using the IceCube neutrino detector we plan to search for high-energy neutrinos emitted from Active Galactic Nuclei (AGN), since AGN are believed to be one of the most promising sources of the most energetic cosmic rays and hence of high-energy neutrinos. We discuss a specific type of AGN which we plan to investigate in more detail with data obtained by the IceCube observatory. The main properties of the AGN category in which we are interested are given by a high-energy jet which is pointing in our line of sight defining a class of AGN, called Blazars, and in particular the ones that are obscured by surrounding dust. The jet-matter interaction is expected to give an increased high-energy neutrino production. The properties of this specific type of AGN are expected to give very distinct features in the electromagnetic spectrum, which are discussed in detail.

  16. AN INFRARED CENSUS OF DUST IN NEARBY GALAXIES WITH SPITZER (DUSTINGS). I. OVERVIEW

    SciTech Connect (OSTI)

    Boyer, Martha L.; Sonneborn, George [Observational Cosmology Laboratory, Code 665, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); McQuinn, Kristen B. W.; Gehrz, Robert D.; Skillman, Evan [Minnesota Institute for Astrophysics, School of Physics and Astronomy, 116 Church Street SE, University of Minnesota, Minneapolis, MN 55455 (United States); Barmby, Pauline [Department of Physics and Astronomy, University of Western Ontario, London, ON, N6A 3K7 (Canada); Bonanos, Alceste Z. [IAASARS, National Observatory of Athens, GR-15236 Penteli (Greece); Gordon, Karl D.; Meixner, Margaret [STScI, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Groenewegen, M. A. T. [Royal Observatory of Belgium, Ringlaan 3, B-1180 Brussels (Belgium); Lagadec, Eric [Laboratoire Lagrange, UMR7293, Univ. Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d'Azur, F-06300 Nice (France); Lennon, Daniel [ESA—European Space Astronomy Centre, Apdo. de Correo 78, E-28691 Villanueva de la Cañada, Madrid (Spain); Marengo, Massimo [Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Sloan, G. C. [Astronomy Department, Cornell University, Ithaca, NY 14853-6801 (United States); Van Loon, Jacco Th. [Astrophysics Group, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG (United Kingdom); Zijlstra, Albert, E-mail: martha.boyer@nasa.gov [Jodrell Bank Centre for Astrophysics, Alan Turing Building, University of Manchester, Manchester M13 9PL (United Kingdom)

    2015-01-01

    Nearby resolved dwarf galaxies provide excellent opportunities for studying the dust-producing late stages of stellar evolution over a wide range of metallicity (–2.7 ? [Fe/H] ? –1.0). Here, we describe DUSTiNGS (DUST in Nearby Galaxies with Spitzer): a 3.6 and 4.5 ?m post-cryogen Spitzer Space Telescope imaging survey of 50 dwarf galaxies within 1.5 Mpc that is designed to identify dust-producing asymptotic giant branch (AGB) stars and massive stars. The survey includes 37 dwarf spheroidal, 8 dwarf irregular, and 5 transition-type galaxies. This near-complete sample allows for the building of statistics on these rare phases of stellar evolution over the full metallicity range. The photometry is >75% complete at the tip of the red giant branch for all targeted galaxies, with the exception of the crowded inner regions of IC 10, NGC 185, and NGC 147. This photometric depth ensures that the majority of the dust-producing stars, including the thermally pulsing AGB stars, are detected in each galaxy. The images map each galaxy to at least twice the half-light radius to ensure that the entire evolved star population is included and to facilitate the statistical subtraction of background and foreground contamination, which is severe at these wavelengths. In this overview, we describe the survey, the data products, and preliminary results. We show evidence for the presence of dust-producing AGB stars in eight of the targeted galaxies, with metallicities as low as [Fe/H] = –1.9, suggesting that dust production occurs even at low metallicity.

  17. Evaluation of Electrostatic Particle Ionization and BioCurtain Technologies to Reduce Dust, Odor and other Pollutants from Broiler Houses Final Report 

    E-Print Network [OSTI]

    Jerez, S.; Muhktar, S.; Faulkner, W.; Casey, K.; Borhan, S.; Hoff, A.; VanDelist, B.

    2011-01-01

    geotextile fabric stretched over a quadrant-shaped, metal frame skeleton, and placed over the exhaust fans of the poultry houses. Air moving out of the house flows down along the top of the quadrant and particulate matter settles out on the ground. The air...-limited to no more than 2 mA to ensure worker and animal safety. The BioCurtain? technology for reducing dust and odor consists of a metal frame structure covered with a woven geotextile fabric and functions by settling airborne dust particles on the ground after...

  18. THE DUST BUDGET OF THE SMALL MAGELLANIC CLOUD: ARE ASYMPTOTIC GIANT BRANCH STARS THE PRIMARY DUST SOURCE AT LOW METALLICITY?

    SciTech Connect (OSTI)

    Boyer, M. L.; Gordon, K. D.; Meixner, M.; Sargent, B. A. [STScI, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Srinivasan, S. [UPMC-CNRS UMR7095, Institut d'Astrophysique de Paris, F-75014 Paris (France); Riebel, D. [Department of Physics and Astronomy, The Johns Hopkins University, Homewood Campus, Baltimore, MD 21218 (United States); McDonald, I. [Jodrell Bank Centre for Astrophysics, Alan Turing Building, University of Manchester, Manchester M13 9PL (United Kingdom); Van Loon, J. Th. [Astrophysics Group, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG (United Kingdom); Clayton, G. C. [Department of Physics and Astronomy, Louisiana State University, 233-A Nicholson Hall, Tower Dr., Baton Rouge, LA 70803-4001 (United States); Sloan, G. C., E-mail: mboyer@stsci.edu [Astronomy Department, Cornell University, Ithaca, NY 14853-6801 (United States)

    2012-03-20

    We estimate the total dust input from the cool evolved stars in the Small Magellanic Cloud, using the 8 {mu}m excess emission as a proxy for the dust-production rate (DPR). We find that asymptotic giant branch (AGB) and red supergiant (RSG) stars produce (8.6-9.5) Multiplication-Sign 10{sup -7} M{sub Sun} yr{sup -1} of dust, depending on the fraction of far-infrared sources that belong to the evolved star population (with 10%-50% uncertainty in individual DPRs). RSGs contribute the least (<4%), while carbon-rich AGB stars (especially the so-called extreme AGB stars) account for 87%-89% of the total dust input from cool evolved stars. We also estimate the dust input from hot stars and supernovae (SNe), and find that if SNe produce 10{sup -3} M{sub Sun} of dust each, then the total SN dust input and AGB input are roughly equivalent. We consider several scenarios of SN dust production and destruction and find that the interstellar medium (ISM) dust can be accounted for solely by stellar sources if all SNe produce dust in the quantities seen around the dustiest examples and if most SNe explode in dense regions where much of the ISM dust is shielded from the shocks. We find that AGB stars contribute only 2.1% of the ISM dust. Without a net positive contribution from SNe to the dust budget, this suggests that dust must grow in the ISM or be formed by another unknown mechanism.

  19. Metal Dusting of Heat-Resistant Alloys

    E-Print Network [OSTI]

    Al-Meshari, Abdulaziz I.

    dusting can also be a serious problem in other industrial sectors including nuclear plants, coal gasification units, ethylene plants, fuel cells, chemical reactors, steam generators, acetic acid cracking furnaces, and waste heat boilers [14] [15] [16... is catalytically accelerated by contact with iron, nickel, and cobalt. For example, coking which is a chronic problem in ethylene furnaces was thought to be caused by the reduction of a porous (Fe, Ni, Cr) spinel oxide layer at the metal surface...

  20. Survivability of dust in tokamaks: dust transport in the divertor sheath

    E-Print Network [OSTI]

    Delzanno, Gian Luca

    2014-01-01

    The survivability of dust being transported in the magnetized sheath near the divertor plate of a tokamak and its impact on the mandatory balance of erosion and redeposition for a steady-state reactor are investigated. Two different divertor scenarios are considered. The first is characterized by an energy flux perpendicular to the plate $q_0\\simeq 1$ MW/m$^2$ typical of current short-pulse tokamaks. The second has $q_0\\simeq 10$ MW/m$^2$ and is relevant to long-pulse machines like ITER or DEMO. It is shown that micrometer dust particles can survive rather easily near the plates of a divertor plasma with $q_0\\simeq 1$ MW/m$^2$ because thermal radiation provides adequate cooling for the dust particle. On the other hand, the survivability of micrometer dust particles near the divertor plates is drastically reduced when $q_0\\simeq 10$ MW/m$^2$. Micrometer dust particles redeposit their material non-locally, leading to a net poloidal mass migration across the divertor. Smaller particles (with radius $\\sim 0.1$ $\\...

  1. Ca depletion and the presence of dust in large scale nebulosities in radiogalaxies (I)

    E-Print Network [OSTI]

    M. Villar-Martin; L. Binette

    1995-11-24

    We show that the study of the Calcium depletion is a valid an highly sensitive method for investigating the chemical and physical history of the very extended ionized nebulae seen around radio galaxies (EELR), massive ellipticals and `cooling flow' galaxies. By observing the near IR spectrum of nebular regions characterized by low excitation emission lines (LINER-like), we can use the intensity of the [CaII]$\\lambda\\lambda 7291,7324$\\AA\\ doublet --relative to other lines, like H$\\alpha$-- to infer the amount of Calcium depletion onto dust grains. The presence of dust in these objects --which does not necessarily result in a measurable level of extinction-- would favour a `galactic debris' rather than a `cooling flow' origin for the emitting gas. Before aplying such test to our data, we study four possible alternative mechanisms to dust depletion and which could have explained the absence of the [CaII] lines: a) ionization of Ca$^+$ from its metastable level, b) thermal ionization of Ca$^+$, c) a high ionization parameter and/or a harder ionizing contiuum than usually asummed and d) matter bounded models associated to a hard ionizing continuum. We show that none of these alternative mechanisms explain the absence of the [CaII] lines, except possibly for the highly ionized EELR where a high ionization parameter is required combined with a soft power law. We thus conclude that for the other low excitation emission regions (cooling flows, liners, low excitation EELR), the abscence of the CaII lines {\\it must} be due to the depletion of Calcium onto dust grains.

  2. Daily Modulation as a Smoking Gun of Dark Matter with Significant Stopping

    E-Print Network [OSTI]

    Chris Kouvaris; Ian M. Shoemaker

    2015-04-01

    We point out that for a range of parameters, the flux of DM may be stopped significantly by its interactions with the Earth. This can significantly degrade the sensitivity of direct detection experiments to DM candidates with large interactions with terrestrial nuclei. We find that a significant region of parameter space remains unconstrained for DM $\\lesssim $ a few GeV. For DM candidates with moderate levels of stopping power, the flux of DM may be blocked from below but not above a detector thereby producing a novel daily modulation. This can be explored by low threshold detectors placed on the surface or in shallow sites in the south hemisphere.

  3. Asymmetric dark matter

    SciTech Connect (OSTI)

    Kumar, Jason

    2014-06-24

    We review the theoretical framework underlying models of asymmetric dark matter, describe astrophysical constraints which arise from observations of neutron stars, and discuss the prospects for detecting asymmetric dark matter.

  4. Design of programmable matter

    E-Print Network [OSTI]

    Knaian, Ara N. (Ara Nerses), 1977-

    2008-01-01

    Programmable matter is a proposed digital material having computation, sensing, actuation, and display as continuous properties active over its whole extent. Programmable matter would have many exciting applications, like ...

  5. Nanodiamond dust and the far-ultraviolet quasar break

    E-Print Network [OSTI]

    Binette, L; Morisset, C; Haro-Corzo, S; De Diego, J A; Mutschke, H; Andersen, A C

    2005-01-01

    We explore the possibility that the steepening observed shortward of 1000A in the energy distribution of quasars may result from absorption by dust, being either intrinsic to the quasar environment or intergalactic. We find that a dust extinction curve consisting of nanodiamonds, composed of terrestrial cubic diamonds or with surface impurities as found in carbonaceous chondrite meteorites, such as Allende, is successful in reproducing the sharp break observed. The intergalactic dust model is partially successful in explaining the shape of the composite energy distribution, but must be discarded in the end, as the amount of crystalline dust required is unreasonable and would imply an improbable fine tuning among the dust formation processes. The alternative intrinsic dust model requires a mixture of both cubic diamonds and Allende nanodiamonds and provide a better fit of the UV break. The gas column densities implied are of the order 10^{20} cm^{-2} assuming solar metallicity for carbon and full depletion of ...

  6. Technology Assessment of Dust Suppression Techniques Applied During Structural Demolition

    SciTech Connect (OSTI)

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

    1998-10-20

    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.

  7. Hot-dark matter, cold dark matter and accelerating universe

    E-Print Network [OSTI]

    Abbas Farmany; Amin Farmany; Mohammad Mahmoodi

    2006-07-07

    The Friedman equation is solved for a universe contains hotdark matter and cold dark matter. In this scenario, hot-dark matter drives an accelerating universe no cold dark matter.

  8. Dynamics of fire plumes and smoke clouds associated with peat and deforestation fires in Indonesia

    E-Print Network [OSTI]

    Tosca, M. G; Randerson, J. T; Zender, C. S; Nelson, D. L; Diner, D. J; Logan, J. A

    2011-01-01

    stereo heights of grassland fire smoke plumes in Australia,of 14 D08207 TOSCA ET AL. : FIRE SMOKE PLUMES ON BORNEO ANDthe 1997 Indonesian forest fire, Geophys. Res. Lett. , 30(

  9. The Influence of Weight Concerns and Weight Control Expectancies in the Smoking Behavior of Spanish Adolescents 

    E-Print Network [OSTI]

    Berrios-Hernandez, Mayra

    2012-07-16

    ) from schools in Alicante, Spain. The students completed questionnaires regarding smoking history and status. They also responded to questions regarding smoking expectancies and weigh concerns. Results suggested differences between smokers...

  10. Introduction Luminance and Chrominance High Frequency Content References Smoke Detection in Stationary Video Using

    E-Print Network [OSTI]

    Knaust, Helmut

    Introduction Luminance and Chrominance High Frequency Content References Smoke Detection and Chrominance High Frequency Content References The Problem The Problem: VIDEO: #12;Introduction Luminance and Chrominance High Frequency Content References Fire/Smoke Detection Techniques Standard techniques for fire

  11. Greater severity of new onset asthma in allergic subjects who smoke: a 10-year longitudinal study

    E-Print Network [OSTI]

    2011-01-01

    new onset asthma in allergic subjects who smoke: a 10-yearnew onset asthma in allergic subjects who smoke: a 10-yearof clinic-referred allergic subjects who developed new onset

  12. Interstellar and ejecta dust in the cas a supernova remnant

    SciTech Connect (OSTI)

    Arendt, Richard G.; Dwek, Eli; Kober, Gladys; Rho, Jeonghee; Hwang, Una

    2014-05-01

    Infrared continuum observations provide a means of investigating the physical composition of the dust in the ejecta and swept up medium of the Cas A supernova remnant (SNR). Using low-resolution Spitzer IRS spectra (5-35 ?m), and broad-band Herschel PACS imaging (70, 100, and 160 ?m), we identify characteristic dust spectra, associated with ejecta layers that underwent distinct nuclear burning histories. The most luminous spectrum exhibits strong emission features at ?9 and 21 ?m and is closely associated with ejecta knots with strong Ar emission lines. The dust features can be reproduced by magnesium silicate grains with relatively low Mg to Si ratios. Another dust spectrum is associated with ejecta having strong Ne emission lines. It has no indication of any silicate features and is best fit by Al{sub 2}O{sub 3} dust. A third characteristic dust spectrum shows features that are best matched by magnesium silicates with a relatively high Mg to Si ratio. This dust is primarily associated with the X-ray-emitting shocked ejecta, but it is also evident in regions where shocked interstellar or circumstellar material is expected. However, the identification of dust composition is not unique, and each spectrum includes an additional featureless dust component of unknown composition. Colder dust of indeterminate composition is associated with emission from the interior of the SNR, where the reverse shock has not yet swept up and heated the ejecta. Most of the dust mass in Cas A is associated with this unidentified cold component, which is ? 0.1 M {sub ?}. The mass of warmer dust is only ?0.04 M {sub ?}.

  13. Tungsten dust impact on ITER-like plasma edge

    SciTech Connect (OSTI)

    Smirnov, R. D. Krasheninnikov, S. I.; Pigarov, A. Yu.; Rognlien, T. D.

    2015-01-15

    The impact of tungsten dust originating from divertor plates on the performance of edge plasma in ITER-like discharge is evaluated using computer modeling with the coupled dust-plasma transport code DUSTT-UEDGE. Different dust injection parameters, including dust size and mass injection rates, are surveyed. It is found that tungsten dust injection with rates as low as a few mg/s can lead to dangerously high tungsten impurity concentrations in the plasma core. Dust injections with rates of a few tens of mg/s are shown to have a significant effect on edge plasma parameters and dynamics in ITER scale tokamaks. The large impact of certain phenomena, such as dust shielding by an ablation cloud and the thermal force on tungsten ions, on dust/impurity transport in edge plasma and consequently on core tungsten contamination level is demonstrated. It is also found that high-Z impurities provided by dust can induce macroscopic self-sustained plasma oscillations in plasma edge leading to large temporal variations of edge plasma parameters and heat load to divertor target plates.

  14. Nanodiamond dust and the energy distribution of quasars

    E-Print Network [OSTI]

    L. Binette; A. C. Andersen; H. Mutschke; S. Haro-Corzo

    2005-09-24

    The spectral energy distribution of quasars shows a sharp steepening of the continuum shortward of ~ 1100 A. The steepening could be a result of dust absorption. We present a dust extinction model which considers crystalline carbon grains and compare it with SMC-like dust extinction consisting of a mixture of silicate grains with graphite or amorphous carbon grains. We show that the sharp break seen in individual quasar spectra of intermediate redshif \\~ 1-2 can be reproduced by dust absorption provided the extinction curve consists of nanodiamonds, composed of terrestial cubic diamonds or of diamonds similar to the presolar nanodiamonds found in primitive meteorites.

  15. Nanodiamond dust and the energy distribution of quasars

    E-Print Network [OSTI]

    Binette, L; Mutschke, H; Haro-Corzo, S

    2005-01-01

    The spectral energy distribution of quasars shows a sharp steepening of the continuum shortward of ~ 1100 A. The steepening could be a result of dust absorption. We present a dust extinction model which considers crystalline carbon grains and compare it with SMC-like dust extinction consisting of a mixture of silicate grains with graphite or amorphous carbon grains. We show that the sharp break seen in individual quasar spectra of intermediate redshif \\~ 1-2 can be reproduced by dust absorption provided the extinction curve consists of nanodiamonds, composed of terrestrial cubic diamonds or of diamonds similar to the presolar nanodiamonds found in primitive meteorites.

  16. Applications of high-speed dust injection to magnetic fusion

    SciTech Connect (OSTI)

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

    2012-08-08

    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.

  17. Secondary Electron Emission from Dust and Its Effect on Charging

    SciTech Connect (OSTI)

    Saikia, B. K.; Kakati, B.; Kausik, S. S. [Centre of Plasma Physics, Institute for Plasma Research, Nazirakhat, Sonapur-782402, Assam (India); Bandyopadhyay, M. [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar-382 428 (India)

    2011-11-29

    Hydrogen plasma is produced in a plasma chamber by striking discharge between incandescent tungsten filaments and the permanent magnetic cage [1], which is grounded. The magnetic cage has a full line cusped magnetic field geometry used to confine the plasma elements. A cylindrical Langmuir probe is used to study the plasma parameters in various discharge conditions. The charge accumulated on the dust particles is calculated using the capacitance model and the dust current is measured by the combination of a Faraday cup and an electrometer at different discharge conditions. It is found Secondary electron emission from dust having low emission yield effects the charging of dust particles in presence of high energetic electrons.

  18. Chemical evolution of galaxies with radiation-driven dust wind

    E-Print Network [OSTI]

    Bekki, Kenji

    2014-01-01

    We discuss how the removal of interstellar dust by radiation pressure of stars influences the chemical evolution of galaxies by using a new one-zone chemical evolution models with dust wind. The removal efficiency of an element (e.g., Fe, Mg, and Ca) through radiation-driven dust wind in a galaxy is assumed to depend both on the dust depletion level of the element in interstellar medium and the total luminosity of the galaxy in the new model. We particularly focus on the time evolution of [alpha/Fe] and its dependence on model parameters for dust wind in this study. The principal results are as follows. The time evolution of [Ca/Fe] is significantly different between models with and without dust wind in the sense that [Ca/Fe] can be systematically lower in the models with dust wind. The time evolution of [Mg/Fe], on the other hand, can not be so different between the models with and without dust wind owing to the lower level of dust depletion for Mg. As a result of this, [Mg/Ca] can be systematically higher i...

  19. Desert dust suppressing precipitation: A possible desertification feedback loop

    E-Print Network [OSTI]

    Daniel, Rosenfeld

    Desert dust suppressing precipitation: A possible desertification feedback loop Daniel Rosenfeld of land use exposing the topsoil can initiate such a desertification feedback process. Satellite

  20. Evaluation of an Electrostatic Dust Removal System with Potential...

    Office of Scientific and Technical Information (OSTI)

    portion of the conveyor, and dust particle size and volume distributions were derived before and after operation. About 10 mm3 volume of carbon and tungsten particles were...

  1. Dynamics of fire plumes and smoke clouds associated with peat and deforestation fires in Indonesia

    E-Print Network [OSTI]

    Tosca, M. G; Randerson, J. T; Zender, C. S; Nelson, D. L; Diner, D. J; Logan, J. A

    2011-01-01

    analyses suggested that direct injection of smoke into the4. Discussion [ 38 ] Direct injection of fire emissions into

  2. UC San Diego (Along with all the UCs) Goes Smoke and Tobacco-Free

    E-Print Network [OSTI]

    California at San Diego, University of

    UC San Diego (Along with all the UCs) Goes Smoke and Tobacco-Free On September 1, 2013, UC San Diego will go completely smoke and tobacco-free on the main campus and other UC San Diego property and universities that are smoke or tobacco-free. Who? This affects everyone on UC San Diego property, including

  3. Optical properties of boreal forest fire smoke derived from Sun photometry

    E-Print Network [OSTI]

    Zeng, Ning

    Optical properties of boreal forest fire smoke derived from Sun photometry N. T. O'Neill,1 T. F 2001; published 13 June 2002. [1] Aerosol optical properties derived from Sun photometry were: Aerosols (0305); KEYWORDS: aerosols, forest fire smoke, Sun photometry, optics 1. Introduction [2] Smoke

  4. ARM - PI Product - Niamey Dust Observations

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska OutreachCalendar NSAProductsMerged and corrected 915Dust Observations

  5. Big Questions: Dark Matter

    SciTech Connect (OSTI)

    Lincoln, Don

    2013-12-05

    Carl Sagan's oft-quoted statement that there are "billions and billions" of stars in the cosmos gives an idea of just how much "stuff" is in the universe. However scientists now think that in addition to the type of matter with which we are familiar, there is another kind of matter out there. This new kind of matter is called "dark matter" and there seems to be five times as much as ordinary matter. Dark matter interacts only with gravity, thus light simply zips right by it. Scientists are searching through their data, trying to prove that the dark matter idea is real. Fermilab's Dr. Don Lincoln tells us why we think this seemingly-crazy idea might not be so crazy after all.

  6. Big Questions: Dark Matter

    ScienceCinema (OSTI)

    Lincoln, Don

    2014-08-07

    Carl Sagan's oft-quoted statement that there are "billions and billions" of stars in the cosmos gives an idea of just how much "stuff" is in the universe. However scientists now think that in addition to the type of matter with which we are familiar, there is another kind of matter out there. This new kind of matter is called "dark matter" and there seems to be five times as much as ordinary matter. Dark matter interacts only with gravity, thus light simply zips right by it. Scientists are searching through their data, trying to prove that the dark matter idea is real. Fermilab's Dr. Don Lincoln tells us why we think this seemingly-crazy idea might not be so crazy after all.

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

    E-Print Network [OSTI]

    Yi, Bingqi

    2013-07-09

    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...

  8. RESEARCH Open Access Transient receptor potential genes, smoking,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    RESEARCH Open Access Transient receptor potential genes, smoking, occupational exposures and cough chemicals and may play an important role in the pathogenesis of cough. The aim was to study the influence of single nucleotide polymorphisms (SNPs) in TRP genes and irritant exposures on cough. Methods: Nocturnal

  9. Smoke emissions in an ecologically sound dryer for coconut

    SciTech Connect (OSTI)

    Lozada, E.P.; Timmins, W.H.; Metcalfe, E. [and others

    1997-12-31

    There are about a million smoke kilns in the world that are being used to dry coconuts produced from over 7,000,000 hectares. Smoke emissions from these kilns are known to contain large quantities of greenhouse and acid rain gases. To minimize the generation of these gases, kilns with better combustion characteristics and heat utilization efficiencies must be used. A possible alternative is a direct-fired, free convection dryer known as the Los Banos (Lozada) Multicrop Dryer. Developed at the University of the Philippines Los Banos, the multicrop dryer consists of a simple burner, a heat distributor and a drying bin. The burner burns coconut shell, corn cob and wood pieces with extremely high efficiency, thus, minimizing fuel consumption and dramatically reducing the release of airborne pollutants. The resulting copra (dried coconut kernel) is practically smoke-free with low levels of poly-aromatic hydrocarbons (PAH`s). Tests have also shown that the gas emissions from the dryer, when compared to that of the traditional smoke kiln, have lower concentrations of CO{sub 2} (1% vs 6%), of CO (50 ppm vs 2000-3000 ppm), of NO{sub x} (5 ppm vs 400 ppm) and SO{sub x} (5 ppm vs 400 ppm).

  10. Automatic Affective Responses to Smoking Cues B. Keith Payne

    E-Print Network [OSTI]

    Automatic Affective Responses to Smoking Cues B. Keith Payne University of North Carolina at Chapel Hill F. Joseph McClernon and Ian G. Dobbins Duke University The authors examined automatic emotional, however, has yielded mixed evidence for whether smokers have favorable or unfavorable automatic responses

  11. ANALYSIS OF DUST DELIQUESCENCE FOR FEP SCREENING

    SciTech Connect (OSTI)

    C. Bryan

    2005-08-26

    The purpose of this report is to evaluate the potential for penetration of the Alloy 22 (UNS N06022) waste package outer barrier by localized corrosion due to the deliquescence of soluble constituents in dust present on waste package surfaces. The results support a recommendation to exclude deliquescence-induced localized corrosion (pitting or crevice corrosion) of the outer barrier from the total system performance assessment for the license application (TSPA-LA). Preparation of this report, and supporting laboratory studies and calculations, were performed as part of the planned effort in Work Package AEBM21, as implemented in ''Technical Work Plan for: Screening Evaluation for Dust Deliquescence and Localized Corrosion'' (BSC 2004 [DIRS 172804]), by Bechtel SAIC Company, LLC, and staff from three national laboratories: Sandia National Laboratories, Lawrence Livermore National Laboratory (LLNL), and Lawrence Berkeley National Laboratory (LBNL). The analysis and conclusions presented in this report are quality affecting, as determined in the controlling technical work plan. A summary of background information, based on work that was not performed under a quality assurance program, is provided as Appendix E. In this instance, the use of unqualified information is provided for transparency and corroboration only, and is clearly separated from uses of qualified information. Thus, the qualification status of this information does not affect the conclusions of this report. The acceptance criteria addressed in Sections 4.2 and 7.2 were changed from the technical work plan in response to review comments received during preparation of this report.

  12. Revisiting Smart Dust with RFID Sensor Networks Michael Buettner

    E-Print Network [OSTI]

    Hochberg, Michael

    of applications such as dense environmental monitoring, sensor rich home automation and smart environmentsRevisiting Smart Dust with RFID Sensor Networks Michael Buettner University of Washington Ben and computation platforms that leverage RFID technology can realize "smart-dust" ap- plications that have eluded

  13. SULFATE AND NITRATE COATINGS ON MINERAL DUSTS: CRYSTALLINE OR AQUEOUS?

    E-Print Network [OSTI]

    SULFATE AND NITRATE COATINGS ON MINERAL DUSTS: CRYSTALLINE OR AQUEOUS? Scot T. Martin, Hui Observational evidence shows that mineral dusts in Asian outflows become coated by sulfates and nitrates. Layer), and the asymmetry parameter. The aqueous coatings also provide milieu for aqueous chemical reactions

  14. A Study of Dust Movement through Construction Barriers 

    E-Print Network [OSTI]

    Zhang, Wei

    2014-12-12

    that models a construction site in a laboratory setting. The results demonstrate movement of the dust occurs with the provision of an opening in a plastic construction wall. The filter collection system analysis showed that the distribution of the dust did...

  15. Concrete Dust Suppression System. Innovative Technology Summary Report

    SciTech Connect (OSTI)

    1998-12-01

    The improved technology is a water-based dust suppression system for controlling concrete dust generated by demolition equipment, in this case a demolition ram. This demonstration was performed to assess the effectiveness of this system to (1) minimize the amount of water used to suppress potentially contaminated dust, (2) focus the water spray on the dust-generating source and (3) minimize the dust cloud generated by the demolition activity. The technology successfully reduced the water required by a factor of eight compared to the traditional (baseline) method, controlled the dust generated, and permitted a reduction in the work force. The water spray can be focused at the ram point, but it is affected by wind. Prior to the use of this dust control system, dust generated by the demolition ram was controlled manually by spraying with fire hoses (the baseline technology). The improved technology is 18% less expensive than the baseline technology for the conditions and parameters of this demonstration, however, the automated system can save up to 80% versus the baseline whenever waste water treatment costs are considered. For demolishing one high-walled room and a long slab with a total of 413 m{sup 3} (14,580 ft{sup 3}) of concrete, the savings are $105,000 (waste water treatment included). The improved technology reduced the need for water consumption and treatment by about 88% which results in most of the savings.

  16. Physical and Chemical Characterization of Kuwaiti Atmospheric Dust and Synthetic Dusts: Effects on the Pressure Drop and Fractional Efficiency of HEPA Filters 

    E-Print Network [OSTI]

    Al-Attar, I.; Wakeman, R. J.; Tarleton, E. S.; Husain, A.

    2010-01-01

    aluminium, calcium, iron and some traces of potassium and magnetism. On the other hand, ASHRAE and SAE coarse dust contains carbon and they also consist of mainly silica. SAE fine dust contains aluminium, calcium and traces of potassium. From... such chemical analysis, the ASHRAE dust seems to be the closest to the Kuwaiti dust from silica-content standpoint. However, analysis of the ASHRAE dust does not show any presence of aluminium, calcium and traces of potassium which are found in the Kuwaiti...

  17. Existence domains of dust-acoustic solitons and supersolitons

    SciTech Connect (OSTI)

    Maharaj, S. K.; Bharuthram, R.; Singh, S. V.; Lakhina, G. S.

    2013-08-15

    Using the Sagdeev potential method, the existence of large amplitude dust-acoustic solitons and supersolitons is investigated in a plasma comprising cold negative dust, adiabatic positive dust, Boltzmann electrons, and non-thermal ions. This model supports the existence of positive potential supersolitons in a certain region in parameter space in addition to regular solitons having negative and positive potentials. The lower Mach number limit for supersolitons coincides with the occurrence of double layers whereas the upper limit is imposed by the constraint that the adiabatic positive dust number density must remain real valued. The upper Mach number limits for negative potential (positive potential) solitons coincide with limiting values of the negative (positive) potential for which the negative (positive) dust number density is real valued. Alternatively, the existence of positive potential solitons can terminate when positive potential double layers occur.

  18. Sheath formation under collisional conditions in presence of dust

    SciTech Connect (OSTI)

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

    2014-08-15

    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.

  19. Transport of charged dust grains into the galactic halo

    E-Print Network [OSTI]

    Khoperskov, S A

    2014-01-01

    We develop a 3D dynamical model of dust outflows from galactic discs. The outflows are initiated by multiple SN explosions in a magnetized interstellar medium (ISM) with a gravitationally stratified density distribution. Dust grains are treated as particles in cells interacting collisionally with gas, and forced by stellar radiation of the disc and Lorenz force. We show that magnetic field plays a crucial role in accelerating the charged dust grains and expelling them out of the disc: in 10--20~Myr they can be elevated at distances up to 10~kpc above the galactic plane. The dust-to-gas ratio in the outflowing medium varies in the range $5 \\cdot 10^{-4} - 5 \\cdot 10^{-2}$ along the vertical stream. Overall the dust mass loss rate depends on the parameters of ISM and may reach up to $3\\times 10^{-2}$~\\Msun~yr$^{-1}$

  20. Nanodiamond dust and the far-ultraviolet quasar break

    E-Print Network [OSTI]

    L. Binette; G. Magris C.; Y. Krongold; C. Morisset; S. Haro-Corzo; J. A. de Diego; H. Mutschke; A. C. Andersen

    2005-05-29

    We explore the possibility that the steepening observed shortward of 1000A in the energy distribution of quasars may result from absorption by dust, being either intrinsic to the quasar environment or intergalactic. We find that a dust extinction curve consisting of nanodiamonds, composed of terrestrial cubic diamonds or with surface impurities as found in carbonaceous chondrite meteorites, such as Allende, is successful in reproducing the sharp break observed. The intergalactic dust model is partially successful in explaining the shape of the composite energy distribution, but must be discarded in the end, as the amount of crystalline dust required is unreasonable and would imply an improbable fine tuning among the dust formation processes. The alternative intrinsic dust model requires a mixture of both cubic diamonds and Allende nanodiamonds and provide a better fit of the UV break. The gas column densities implied are of the order 10^{20} cm^{-2} assuming solar metallicity for carbon and full depletion of carbon into dust. The absorption only occurs in the ultraviolet and is totally negligible in the visible. The minimum dust mass required is of the order ~ 0.003 r_{pc}^{2}M_o, where r_{pc} is the distance in parsec between the dust screen and the continuum source. The intrinsic dust model reproduces the flux {\\it rise} observed around 660A in key quasar spectra quite well. We present indirect evidence of a shallow continuum break near 670A (18.5 eV), which would be intrinsic to the quasar continuum.

  1. A long Saharan dust event over the western Mediterranean: Lidar, Sun photometer observations, and regional dust modeling

    E-Print Network [OSTI]

    over the Mediterranean region (http://www.bsc.es/projects/earthscience/ DREAM/) considering four of dust exported annually from northern Africa (Sahara-Sahel region) are still not reliable, and range]. Once in the atmosphere, dust particles interact with solar and thermal radiation, modulating the Earth

  2. Matter: Space without Time

    E-Print Network [OSTI]

    Yousef Ghazi-Tabatabai

    2012-11-19

    While Quantum Gravity remains elusive and Quantum Field Theory retains the interpretational difficulties of Quantum Mechanics, we have introduced an alternate approach to the unification of particles, fields, space and time, suggesting that the concept of matter as space without time provides a framework which unifies matter with spacetime and in which we anticipate the development of complete theories (ideally a single unified theory) describing observed 'particles, charges, fields and forces' solely with the geometry of our matter-space-time universe.

  3. Cosmology with Mimetic Matter

    SciTech Connect (OSTI)

    Chamseddine, Ali H.; Mukhanov, Viatcheslav; Vikman, Alexander E-mail: viatcheslav.Mukhanov@lmu.de

    2014-06-01

    We consider minimal extensions of the recently proposed Mimetic Dark Matter and show that by introducing a potential for the mimetic non-dynamical scalar field we can mimic nearly any gravitational properties of the normal matter. In particular, the mimetic matter can provide us with inflaton, quintessence and even can lead to a bouncing nonsingular universe. We also investigate the behaviour of cosmological perturbations due to a mimetic matter. We demonstrate that simple mimetic inflation can produce red-tilted scalar perturbations which are largely enhanced over gravity waves.

  4. Energy Matters Mailbag

    Broader source: Energy.gov [DOE]

    This edition of the mailbag tackles follow-up questions from our Energy Matters discussion on breaking our reliance on foreign oil.

  5. Dipolar Dark Matter

    E-Print Network [OSTI]

    Luc Blanchet; Lavinia Heisenberg

    2015-05-19

    Massive gravity theories have been developed as viable IR modifications of gravity motivated by dark energy and the problem of the cosmological constant. On the other hand, modified gravity and modified dark matter theories were developed with the aim of solving the problems of standard cold dark matter at galactic scales. Here we propose to adapt the framework of ghost-free massive bigravity theories to reformulate the problem of dark matter at galactic scales. We investigate a promising alternative to dark matter called dipolar dark matter (DDM) in which two different species of dark matter are separately coupled to the two metrics of bigravity and are linked together by an internal vector field. We show that this model successfully reproduces the phenomenology of dark matter at galactic scales (i.e. MOND) as a result of a mechanism of gravitational polarisation. The model is safe in the gravitational sector, but because the two types of dark matter interact through the vector field, a ghostly degree of freedom in the decoupling limit is reintroduced in the dark matter sector. Crucial questions to address in future work is whether the polarisation mechanism can be realized in absence of ghosts, and what are the cosmological implications of the model.

  6. A new method to generate dust with astrophysical properties

    SciTech Connect (OSTI)

    Hansen, J F; van Breugel, W; Bringa, E M; Graham, G A; Remington, B A; Taylor, E A; Tielens, A G

    2010-04-21

    In interstellar and interplanetary space, the size distribution and composition of dust grains play an important role. For example, dust grains determine optical and ultraviolet extinction levels in astronomical observations, dominate the cooling rate of our Galaxy, and sets the thermal balance and radiative cooling rates in molecular clouds, which are the birth place of stars. Dust grains are also a source of damage and failure to space hardware and thus present a hazard to space flight. To model the size distribution and composition of dust grains, and their effect in the above scenarios, it is vital to understand the mechanism of dust-shock interaction. We demonstrate a new experiment which employs a laser to subject dust grains to pressure spikes similar to those of colliding astrophysical dust, and which accelerates the grains to astrophysical velocities. The new method generates much larger data sets than earlier methods; we show how large quantities (thousands) of grains are accelerated at once, rather than accelerating individual grains, as is the case of earlier methods using electric fields.

  7. The gravitational redshift of photons traversing a collapsing dust cloud and observable consequences

    E-Print Network [OSTI]

    Néstor Ortiz; Olivier Sarbach

    2014-11-24

    We analyze the frequency shift of photons propagating on an asymptotically flat spacetime describing a collapsing, spherical dust cloud. We focus on the case where the interaction of the photons with the matter can be neglected. Under fairly general assumptions on the initial data characterizing the collapse, we show that photons with zero angular momentum which travel from past to future null infinity, crossing the collapsing cloud through its center, are always redshifted with respect to stationary observers. We compute this redshift as a function of proper time of a distant stationary observer and discuss its dependency on the mass distribution of the cloud. Possible implications of this redshift effect for weak cosmic censorship and light propagation in cosmological spacetimes are also briefly discussed.

  8. Alignment of Dust with Magnetic Inclusions: Radiative Torques and Superparamagnetic Barnett and Nuclear Relaxation

    E-Print Network [OSTI]

    A. Lazarian; T. Hoang

    2008-01-03

    We consider grains with superparamagnetic inclusions and report two new condensed matter effects that can enhance the internal relaxation of the energy of a wobbling grain, namely, superparamagnetic Barnett relaxation, as well as, an increase of frequencies for which nuclear relaxation becomes important. This findings extends the range of grain sizes for which grains are thermally trapped, i.e. rotate thermally, in spite of the presence of uncompensated pinwheel torques. In addition, we show that the alignment of dust grains by radiative torques gets modified for superparamagnetic grains, with grains obtaining perfect alignment with respect to magnetic fields as soon as the grain gaseous randomization time gets larger than that of paramagnetic relaxation. The same conclusion is valid for the mechanical alignment of helical grains. If observations confirm that the degrees of alignment are higher than radiative torques can produce alone, this may be a proof of the presence of superparamagentic inclusions.

  9. Charged annular disks and Reissner-Nordstroem type black holes from extremal dust

    SciTech Connect (OSTI)

    Lora-Clavijo, F. D.; Ospina-Henao, P. A.; Pedraza, J. F.

    2010-10-15

    We present the first analytical superposition of a charged black hole with an annular disk of extremal dust. In order to obtain the solutions, we first solve the Einstein-Maxwell field equations for sources that represent disklike configurations of matter in confomastatic spacetimes by assuming a functional dependence among the metric function, the electric potential, and an auxiliary function, which is taken as a solution of the Laplace equation. We then employ the Lord Kelvin inversion method applied to models of finite extension in order to obtain annular disks. The structures obtained extend to infinity, but their total masses are finite and all the energy conditions are satisfied. Finally, we observe that the extremal Reissner-Nordstroem black hole can be embedded into the center of the disks by adding a boundary term in the inversion.

  10. Direct dark matter searches—Test of the Big Bounce Cosmology

    SciTech Connect (OSTI)

    Cheung, Yeuk-Kwan E.; Vergados, J.D. E-mail: vergados@uoi.gr

    2015-02-01

    We consider the possibility of using dark matter particle's mass and its interaction cross section as a smoking gun signal of the existence of a Big Bounce at the early stage in the evolution of our currently observed universe. A study of dark matter production in the pre-bounce contraction and the post bounce expansion epochs of this universe reveals a new venue for achieving the observed relic abundance of our present universe. Specifically, it predicts a characteristic relation governing a dark matter mass and interaction cross section and a factor of 1/2 in thermally averaged cross section, as compared to the non-thermal production in standard cosmology, is needed for creating enough dark matter particle to satisfy the currently observed relic abundance because dark matter is being created during the pre-bounce contraction, in addition to the post-bounce expansion. As the production rate is lower than the Hubble expansion rate information of the bounce universe evolution is preserved. Therefore once the value of dark matter mass and interaction cross section are obtained by direct detection in laboratories, this alternative route becomes a signature prediction of the bounce universe scenario. This leads us to consider a scalar dark matter candidate, which if it is light, has important implications on dark matter searches.

  11. Energy and matter

    E-Print Network [OSTI]

    Gobato, Ricardo; Fedrigo, Desire Francine Gobato

    2015-01-01

    Our work is an approach between matter and energy. Using the famous equation E = mc^2, Einstein and the Law of Universal Gravitation of Newton, we estimate that a small amount matter converted into energy is needed to lift, using the gravitational potential energy equation on the surface, a mountain of solid iron or even Mount Everest.

  12. Dark matter searches

    E-Print Network [OSTI]

    Baudis, Laura

    2015-01-01

    One of the major challenges of modern physics is to decipher the nature of dark matter. Astrophysical observations provide ample evidence for the existence of an invisible and dominant mass component in the observable universe, from the scales of galaxies up to the largest cosmological scales. The dark matter could be made of new, yet undiscovered elementary particles, with allowed masses and interaction strengths with normal matter spanning an enormous range. Axions, produced non-thermally in the early universe, and weakly interacting massive particles (WIMPs), which froze out of thermal equilibrium with a relic density matching the observations, represent two well-motivated, generic classes of dark matter candidates. Dark matter axions could be detected by exploiting their predicted coupling to two photons, where the highest sensitivity is reached by experiments using a microwave cavity permeated by a strong magnetic field. WIMPs could be directly observed via scatters off atomic nuclei in underground, ultr...

  13. Dark matter axions

    E-Print Network [OSTI]

    P. Sikivie

    2009-09-04

    The hypothesis of an `invisible' axion was made by Misha Shifman and others, approximately thirty years ago. It has turned out to be an unusually fruitful idea, crossing boundaries between particle physics, astrophysics and cosmology. An axion with mass of order $10^{-5}$ eV (with large uncertainties) is one of the leading candidates for the dark matter of the universe. It was found recently that dark matter axions thermalize and form a Bose-Einstein condensate (BEC). Because they form a BEC, axions differ from ordinary cold dark matter (CDM) in the non-linear regime of structure formation and upon entering the horizon. Axion BEC provides a mechanism for the production of net overall rotation in dark matter halos, and for the alignment of cosmic microwave anisotropy multipoles. Because there is evidence for these phenomena, unexplained with ordinary CDM, an argument can be made that the dark matter is axions.

  14. Dissipation of dark matter

    E-Print Network [OSTI]

    Hermano Velten; Dominik J. Schwarz

    2012-10-01

    Fluids often display dissipative properties. We explore dissipation in the form of bulk viscosity in the cold dark matter fluid. We constrain this model using current data from supernovae, baryon acoustic oscillations and the cosmic microwave background. Considering the isotropic and homogeneous background only, viscous dark matter is allowed to have a bulk viscosity $\\lesssim 10^7$ Pa$\\cdot$s, also consistent with the expected integrated Sachs-Wolfe effect (which plagues some models with bulk viscosity). We further investigate the small-scale formation of viscous dark matter halos, which turns out to place significantly stronger constraints on the dark matter viscosity. The existence of dwarf galaxies is guaranteed only for much smaller values of the dark matter viscosity, $\\lesssim 10^{-3}$ Pa$\\cdot$s.

  15. An Alternate Approach to Determine the Explosibility of Dusts 

    E-Print Network [OSTI]

    Ganesan, Balaji

    2013-12-04

    Figure 3. A deflagration fueled by corn starch in the CAAQES chamber at 50 g m-3 ..... 20 Figure 4. The characteristic PvT curves obtained for corn starch at a concentration of 50 g m-3 for three replications... ........................................................................ 28 Figure 7. Explosibility tests conducted for CGD in the CAAQES chamber ................... 36 Figure 8. The characteristic PvT curves for gin dust at a concentration of 1000 g m-3 ... 36 Figure 9. A dust explosion fueled by Dust XX at a...

  16. Spatiotemporal evolution of dielectric driven cogenerated dust density waves

    SciTech Connect (OSTI)

    Sarkar, Sanjib; Bose, M. [Department of Physics, Jadavpur University, Kolkata 700032 (India)] [Department of Physics, Jadavpur University, Kolkata 700032 (India); Mukherjee, S. [FCIPT, Institute for Plasma Research, Gandhinagar 382428 (India)] [FCIPT, Institute for Plasma Research, Gandhinagar 382428 (India); Pramanik, J. [Kharagpur College, Kharagpur 721305, West Bengal (India)] [Kharagpur College, Kharagpur 721305, West Bengal (India)

    2013-06-15

    An experimental observation of spatiotemporal evolution of dust density waves (DDWs) in cogenerated dusty plasma in the presence of modified field induced by glass plate is reported. Various DDWs, such as vertical, oblique, and stationary, were detected simultaneously for the first time. Evolution of spatiotemporal complexity like bifurcation in propagating wavefronts is also observed. As dust concentration reaches extremely high value, the DDW collapses. Also, the oblique and nonpropagating mode vanishes when we increase the number of glass plates, while dust particles were trapped above each glass plates showing only vertical DDWs.

  17. The peculiar dust shell of Nova DZ Cru (2003).

    SciTech Connect (OSTI)

    Evans, A.; Gehrz, R. D.; Woodward, C. E.; Helton, L. A.; Rushton, M. T.; Bode, M. F.; Krautter, J.; Lyke, J.; Lynch, D. K.; Ness, J.-U.; Starrfield, S.; Truran, J. W.; Wagner, R. M.; Physics; Keele Univ.; Univ. of Minnesota; Univ. of Central Lancashire; Liverpool John Moores Univ.; Zentrum fur Astronomie der Univ. Heidelberg; M. W. Keck Observatory; The Aerospace Corp.; European Space Astronomy Centre; Arizona State Univ.; Univ. of Chicago; Large Binocular Telscope Observatory

    2010-01-01

    We present Spitzer Space Telescope observations of the 'peculiar variable' DZ Cru, identified by Rushton et al. as a classical nova. A dust shell, on which are superimposed a number of features, is prominent in the 5-35 {micro}m range some 4 yr after eruption. We suggest that the dust in DZ Cru is primarily hydrogenated amorphous carbon in which aliphatic bands currently predominate and which may become either predominantly aromatic as the dust is photoprocessed by ultraviolet radiation from the stellar remnant or more likely completely destroyed.

  18. Reducing dust emissions at OAO Alchevskkoks coke battery 10A

    SciTech Connect (OSTI)

    T.F. Trembach; E.N. Lanina [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

    2009-07-15

    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.

  19. Relativistic Laser-Matter Interactions

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

    Relativistic Laser-Matter Interactions Relativistic Laser-Matter Interactions Enabling the next generation of intense particle accelerators Contact Juan Fernandez (505) 667-6575...

  20. Naked singularity formation for higher dimensional inhomogeneous dust collapse

    E-Print Network [OSTI]

    Ujjal Debnath; Subenoy Chakraborty

    2003-02-28

    We investigate the occurrence and nature of a naked singularity in the gravitational collapse of an inhomogeneous dust cloud described by higher dimensional Tolman-Bondi space-time. The naked singularities are found to be gravitationally strong.

  1. Assessment of suspended dust from pipe rattling operations 

    E-Print Network [OSTI]

    Park, Ju-Myon

    2006-10-30

    . The PM10 sampler provides a reasonable estimate of the thoracic particulate fraction. The RespiCon sampler provides an unbiased estimate of respirable, thoracic, and inhalable fractions. DustTrak and SidePak monitors provide relative particle...

  2. Environmental Scientists Find Antibiotics, Bacteria, Resistance Genes in Feedlot Dust

    E-Print Network [OSTI]

    Rock, Chris

    Environmental Scientists Find Antibiotics, Bacteria, Resistance Genes in Feedlot Dust :: Texas Tech Today http://today.ttu.edu/2015/01/environmental-scientists-find-antibiotics Print Email + Font - Font Environmental Scientists Find Antibiotics, Bacteria, Resistance Genes

  3. Evaluation and recommendations for reduction of a silica dust exposure 

    E-Print Network [OSTI]

    Gruben, Raymond L

    2000-01-01

    A brick cutting task was identified as a job with a potential overexposure to crystalline silica dust. A sampling plan was proposed and implemented. Both the NIOSH approved method, using cyclone filters to select out ...

  4. Axion BEC Dark Matter

    E-Print Network [OSTI]

    Erken, Ozgur; Tam, Heywood; Yang, Qiaoli

    2011-01-01

    Cold dark matter axions thermalize through gravitational self-interactions and form a Bose-Einstein condensate when the photon temperature reaches approximately 500 eV. Axion Bose-Einstein condensation provides an opportunity to distinguish axions from the other dark matter candidates on the basis of observation. The rethermalization of axions that are about to fall in a galactic potential well causes them to acquire net overall rotation, whereas ordinary cold dark matter falls in with an irrotational velocity field. The inner caustics of galactic halos are different in the two cases.

  5. Axion BEC Dark Matter

    E-Print Network [OSTI]

    Ozgur Erken; Pierre Sikivie; Heywood Tam; Qiaoli Yang

    2011-11-16

    Cold dark matter axions thermalize through gravitational self-interactions and form a Bose-Einstein condensate when the photon temperature reaches approximately 500 eV. Axion Bose-Einstein condensation provides an opportunity to distinguish axions from the other dark matter candidates on the basis of observation. The rethermalization of axions that are about to fall in a galactic potential well causes them to acquire net overall rotation, whereas ordinary cold dark matter falls in with an irrotational velocity field. The inner caustics of galactic halos are different in the two cases.

  6. Dark Matter 2014

    E-Print Network [OSTI]

    Marc Schumann

    2015-01-06

    This article gives an overview on the status of experimental searches for dark matter at the end of 2014. The main focus is on direct searches for weakly interacting massive particles (WIMPs) using underground-based low-background detectors, especially on the new results published in 2014. WIMPs are excellent dark matter candidates, predicted by many theories beyond the standard model of particle physics, and are expected to interact with the target nuclei either via spin-independent (scalar) or spin-dependent (axial-vector) couplings. Non-WIMP dark matter candidates, especially axions and axion-like particles are also briefly discussed.

  7. Bipolar charging of dust particles under ultraviolet radiation

    SciTech Connect (OSTI)

    Filippov, A. V. Babichev, V. N.; Fortov, V. E.; Gavrikov, A. V.; Pal', A. F.; Petrov, O. F.; Starostin, A. N.; Sarkarov, N. E.

    2011-05-15

    The photoemission charging of dust particles under ultraviolet radiation from a xenon lamp has been investigated. The velocities of yttrium dust particles with a work function of 3.3 eV and their charges have been determined experimentally; the latter are about 400-500 and about 100 elementary charges per micron of radius for the positively and negatively charged fractions, respectively. The dust particle charging and the dust cloud evolution in a photoemission cell after exposure to an ultraviolet radiation source under the applied voltage have been simulated numerically. The photoemission charging of dust particles has been calculated on the basis of nonlocal and local charging models. Only unipolar particle charging is shown to take place in a system of polydisperse dust particles with the same photoemission efficiency. It has been established that bipolar charging is possible in the case of monodisperse particles with different quantum efficiencies. Polydispersity in this case facilitates the appearance of oppositely charged particles in a photoemission plasma.

  8. HTGR Dust Safety Issues and Needs for Research and Development

    SciTech Connect (OSTI)

    Paul W. Humrickhouse

    2011-06-01

    This report presents a summary of high temperature gas-cooled reactor dust safety issues. It draws upon a literature review and the proceedings of the Very High Temperature Reactor Dust Assessment Meeting held in Rockville, MD in March 2011 to identify and prioritize the phenomena and issues that characterize the effect of carbonaceous dust on high temperature reactor safety. It reflects the work and input of approximately 40 participants from the U.S. Department of Energy and its National Labs, the U.S. Nuclear Regulatory Commission, industry, academia, and international nuclear research organizations on the topics of dust generation and characterization, transport, fission product interactions, and chemical reactions. The meeting was organized by the Idaho National Laboratory under the auspices of the Next Generation Nuclear Plant Project, with support from the U.S. Nuclear Regulatory Commission. Information gleaned from the report and related meetings will be used to enhance the fuel, graphite, and methods technical program plans that guide research and development under the Next Generation Nuclear Plant Project. Based on meeting discussions and presentations, major research and development needs include: generating adsorption isotherms for fission products that display an affinity for dust, investigating the formation and properties of carbonaceous crust on the inside of high temperature reactor coolant pipes, and confirming the predominant source of dust as abrasion between fuel spheres and the fuel handling system.

  9. THE TRANSIT LIGHT CURVE OF AN EXOZODIACAL DUST CLOUD

    SciTech Connect (OSTI)

    Stark, Christopher C.

    2011-10-15

    Planets embedded within debris disks gravitationally perturb nearby dust and can create clumpy, azimuthally asymmetric circumstellar ring structures that rotate in lock with the planet. The Earth creates one such structure in the solar zodiacal dust cloud. In an edge-on system, the dust 'clumps' periodically pass in front of the star as the planet orbits, occulting and forward-scattering starlight. In this paper, we predict the shape and magnitude of the corresponding transit signal. To do so, we model the dust distributions of collisional, steady-state exozodiacal clouds perturbed by planetary companions. We examine disks with dusty ring structures formed by the planet's resonant trapping of in-spiraling dust for a range of planet masses and semi-major axes, dust properties, and disk masses. We synthesize edge-on images of these models and calculate the transit signatures of the resonant ring structures. The transit light curves created by dusty resonant ring structures typically exhibit two broad transit minima that lead and trail the planetary transit. We find that Jupiter-mass planets embedded within disks hundreds of times denser than our zodiacal cloud can create resonant ring structures with transit depths up to {approx}10{sup -4}, possibly detectable with Kepler. Resonant rings produced by planets more or less massive than Jupiter produce smaller transit depths. Observations of these transit signals may provide upper limits on the degree of asymmetry in exozodiacal clouds.

  10. Sensitivity Study of the Effects of Mineral Dust Particle Nonsphericity and Thin Cirrus Clouds on MODIS Dust Optical Depth Retrievals and Direct Radiative Forcing Calculations 

    E-Print Network [OSTI]

    Feng, Qian

    2011-10-21

    A special challenge posed by mineral dust aerosols is associated with their predominantly nonspherical particle shapes. In the present study, the scattering and radiative properties for nonspherical mineral dust aerosols at violet-to-blue (0.412, 0...

  11. Impact of Desert Dust Radiative Forcing on Sahel Precipitation: Relative Importance of Dust Compared to Sea Surface Temperature Variations, Vegetation Changes, and Greenhouse Gas Warming

    E-Print Network [OSTI]

    2007-01-01

    Understanding the 30-year Barbados desert dust record. J.on mineral dust in the Barbados trade winds. Nature, 320,late 1960s to 1980s over Barbados (13°N, 60°W; Prospero and

  12. Global impact of smoke aerosols from landscape fires on climate and the Hadley circulation

    E-Print Network [OSTI]

    Tosca, M. G; Randerson, J. T; Zender, C. S

    2013-01-01

    on stand age in a boreal forest fire chronosequence, J.released from peat and forest fires in Indonesia duringevidence of smoke from forest fires inhibiting rainfall,

  13. Soil Sampling At Valley Of Ten Thousand Smokes Region Area (Kodosky...

    Open Energy Info (EERE)

    Soil Sampling At Valley Of Ten Thousand Smokes Region Area (Kodosky & Keith, 1993) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Soil Sampling...

  14. Smoking and Ischemic Heart Disease Disparities Between Studies, Genders, Times, and Socioeconomic Strata

    E-Print Network [OSTI]

    Leistikow, Bruce N.

    2009-01-01

    predictors of coronary heart disease among women. Americanon the risk for coronary heart disease even stronger thanx Smoking and Ischemic Heart Disease Disparities Between

  15. Relationship Between Daily Exposure to Biomass Fuel Smoke and Blood Pressure in High-Altitude Peru

    E-Print Network [OSTI]

    2015-01-01

    Between Daily Exposure to Biomass Fuel Smoke and BloodHousehold air pollution from biomass fuel use affects 3relationship between biomass fuel use and blood pressure. We

  16. Toward resolution-independent dust emissions in global models: Impacts on the seasonal and spatial distribution of dust

    E-Print Network [OSTI]

    Pierce, J. R.

    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 ...

  17. THE ABSENCE OF COLD DUST AND THE MINERALOGY AND ORIGIN OF THE WARM DUST ENCIRCLING BD +20 307

    SciTech Connect (OSTI)

    Weinberger, A. J.; Becklin, E. E.; Zuckerman, B.; Song, I. E-mail: becklin@astro.ucla.edu E-mail: song@uga.edu

    2011-01-10

    Spitzer Space Telescope photometry and spectroscopy of BD +20 307 show that all of the dust around this remarkable Gyr-old spectroscopic binary arises within 1 AU. No additional cold dust is needed to fit the infrared excess. Peaks in the 10 and 20 {mu}m spectrum are well fit with small silicates that should be removed on a timescale of years from the system. This is the dustiest star known for its age, which is {approx}>1 Gyr. The dust cannot arise from a steady-state collisional cascade. A catastrophic collision of two rocky, planetary-scale bodies in the terrestrial zone is the most likely source for this warm dust because it does not require a reservoir of planetesimals in the outer system.

  18. Matter & Energy Civil Engineering

    E-Print Network [OSTI]

    Rogers, John A.

    See Also: Matter & Energy Detectors· Optics· Civil Engineering· Engineering· Nature of Water Yonggang Huang, Joseph Cummings Professor of Civil and Environmental Engineering and Mechanical Engineering· Electronics· Reference Photography· Infrared· Mechanical engineering · Optics· ScienceDaily (Jan. 17, 2011

  19. Gaseous dark matter detectors

    E-Print Network [OSTI]

    Martoff, C. J.

    Dark matter (DM) detectors with directional sensitivity have the potential of yielding an unambiguous positive observation of WIMPs as well as discriminating between galactic DM halo models. In this paper, we introduce the ...

  20. Matter & Energy Electronics

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    See also: Matter & Energy Detectors· Electronics· Technology· Medical Technology· Weapons Technology · Organic Chemistry· Reference Hydrogen chloride· Photography· Catalytic converter· Nanomedicine a series of tiny colored dots ­ each a different pigment ­ on an inert backing such as paper, plastic

  1. The Heart of Matter

    E-Print Network [OSTI]

    Rohini M. Godbole

    2010-06-30

    In this article I trace the development of the human understanding of the "Heart of Matter" from early concepts of "elements" (or alternatively "Panchmahabhootas") to the current status of "quarks" and "leptons" as the fundamental constituents of matter, interacting together via exchange of the various force carrier particles called "gauge bosons" such as the photon, W/Z-boson etc. I would like to show how our understanding of the fundamental constituents of matter has gone hand in hand with our understanding of the fundamental forces in nature. I will also outline how the knowledge of particle physics at the "micro" scale of less than a Fermi(one millionth of a nanometer), enables us to offer explanations of Cosmological observations at the "macro" scale. Consequently these observations, may in turn, help us address some very fundamental questions of the Physics at the "Heart of the Matter".

  2. Hot and dark matter

    E-Print Network [OSTI]

    D'Eramo, Francesco

    2012-01-01

    In this thesis, we build new Effective Field Theory tools to describe the propagation of energetic partons in hot and dense media, and we propose two new reactions for dark matter in the early universe. In the first part, ...

  3. Dark matter searches

    E-Print Network [OSTI]

    Laura Baudis

    2015-09-02

    One of the major challenges of modern physics is to decipher the nature of dark matter. Astrophysical observations provide ample evidence for the existence of an invisible and dominant mass component in the observable universe, from the scales of galaxies up to the largest cosmological scales. The dark matter could be made of new, yet undiscovered elementary particles, with allowed masses and interaction strengths with normal matter spanning an enormous range. Axions, produced non-thermally in the early universe, and weakly interacting massive particles (WIMPs), which froze out of thermal equilibrium with a relic density matching the observations, represent two well-motivated, generic classes of dark matter candidates. Dark matter axions could be detected by exploiting their predicted coupling to two photons, where the highest sensitivity is reached by experiments using a microwave cavity permeated by a strong magnetic field. WIMPs could be directly observed via scatters off atomic nuclei in underground, ultra low-background detectors, or indirectly, via secondary radiation produced when they pair annihilate. They could also be generated at particle colliders such as the LHC, where associated particles produced in the same process are to be detected. After a brief motivation and an introduction to the phenomenology of particle dark matter detection, I will discuss the most promising experimental techniques to search for axions and WIMPs, addressing their current and future science reach, as well as their complementarity.

  4. Training of a smoke detecting domestic security dog 

    E-Print Network [OSTI]

    Kirk, Douglas Walter

    1976-01-01

    domestic security . 111 113 INTRODUCTION The present study involved a test of training procedures that could be used to condition a dog to search a house at predetermined times for evidence of smoke produced by fire without the aid of a human handler... in the suspected man. (On the other hand, the dogs may be receiving cues from the handler that the man sought is guilty of some crime. ) Schmid (1935) stressed the importance of factors such as conditions in which a trail is laid, substances carried from...

  5. Responsibility and resistance : children and young people’s accounts of smoking in the home and car 

    E-Print Network [OSTI]

    Rowa-Dewar, Neneh

    2013-07-06

    Following the implementation of the smokefree law in 2006, which formed part of the Smoking, Health and Social Care (Scotland) Act 2005, smoking in enclosed public spaces has been prohibited in Scotland. The law has led ...

  6. Infant Formula with Docosahexaenoic Acid, Maternal Smoking, and Body Mass Index of Children To Six Years of Age

    E-Print Network [OSTI]

    Currie, Lindsey Marie

    2012-05-31

    Research findings have suggested no differences in growth among term infants fed DHA supplemented formulas. Studies have found maternal smoking decreases length and increases weight of children. No studies have analyzed maternal smoking and DHA...

  7. Environmental Tobacco Smoke Effects on the Primary Lipids of Lung Surfactant

    E-Print Network [OSTI]

    Zasadzinski, Joseph A.

    Environmental Tobacco Smoke Effects on the Primary Lipids of Lung Surfactant Frank Bringezu,, Kent. In Final Form: December 2, 2002 The effects of environmental tobacco smoke (ETS) on lung surfactant are difficult to determine from analysis of human and animal lung lavage due to large variations in surfactant

  8. mPuff: Automated Detection of Cigarette Smoking Puffs from Respiration Measurements

    E-Print Network [OSTI]

    Kumar, Santosh

    that accounts for one in five deaths in the United States. Extensive research is conducted on devel- oping deaths in the United States [24]. Smokers die 13-14 years younger and cost $193 billion annually [1 effective smoking cessation programs. Most smoking cessation programs achieve low success rate because

  9. Use of Semantic Features to Classify Patient Smoking Status Patrick J. McCormick, MEng1

    E-Print Network [OSTI]

    challenge for teams to use whatever tools at their disposal to build automated smoking classifiers. Teams and liability concerns. The recent smoking classification challenge by i2b2 (Informatics for Integrating Biology using discharge summaries. Source data originated from hospitals within the Partners HealthCare system

  10. The Impact of Dust Evolution and Photoevaporation on Disk Dispersal

    E-Print Network [OSTI]

    Gorti, Uma; Dullemond, Cornelis

    2015-01-01

    Protoplanetary disks are dispersed by viscous evolution and photoevaporation in a few million years; in the interim small, sub-micron sized dust grains must grow and form planets. The time-varying abundance of small grains in an evolving disk directly affects gas heating by far-ultraviolet photons, while dust evolution affects photoevaporation by changing the disk opacity and resulting penetration of FUV photons in the disk. Photoevaporative flows, in turn, selectively carry small dust grains leaving the larger particles---which decouple from the gas---behind in the disk. We study these effects by investigating the evolution of a disk subject to viscosity, photoevaporation by EUV, FUV and X-rays, dust evolution, and radial drift using a 1-D multi-fluid approach (gas + different dust grain sizes) to solve for the evolving surface density distributions. The 1-D evolution is augmented by 1+1D models constructed at each epoch to obtain the instantaneous disk structure and determine photoevaporation rates. The imp...

  11. Associations between bacterial communities of house dust and infant gut

    SciTech Connect (OSTI)

    Konya, T.; Koster, B.; Maughan, H.; Escobar, M.; Azad, M.B.; Guttman, D.S.; Sears, M.R.; Becker, A.B.; Brook, J.R.; Takaro, T.K.; Kozyrskyj, A.L.; Scott, J.A.

    2014-05-01

    The human gut is host to a diverse and abundant community of bacteria that influence health and disease susceptibility. This community develops in infancy, and its composition is strongly influenced by environmental factors, notably perinatal anthropogenic exposures such as delivery mode (Cesarean vs. vaginal) and feeding method (breast vs. formula); however, the built environment as a possible source of exposure has not been considered. Here we report on a preliminary investigation of the associations between bacteria in house dust and the nascent fecal microbiota from 20 subjects from the Canadian Healthy Infant Longitudinal Development (CHILD) Study using high-throughput sequence analysis of portions of the 16S rRNA gene. Despite significant differences between the dust and fecal microbiota revealed by Nonmetric Multidimensional Scaling (NMDS) analysis, permutation analysis confirmed that 14 bacterial OTUs representing the classes Actinobacteria (3), Bacilli (3), Clostridia (6) and Gammaproteobacteria (2) co-occurred at a significantly higher frequency in matched dust–stool pairs than in randomly permuted pairs, indicating an association between these dust and stool communities. These associations could indicate a role for the indoor environment in shaping the nascent gut microbiota, but future studies will be needed to confirm that our findings do not solely reflect a reverse pathway. Although pet ownership was strongly associated with the presence of certain genera in the dust for dogs (Agrococcus, Carnobacterium, Exiguobacterium, Herbaspirillum, Leifsonia and Neisseria) and cats (Escherichia), no clear patterns were observed in the NMDS-resolved stool community profiles as a function of pet ownership.

  12. Elasticity of a percolation system: silica smoke J. FORSMAN',J. P. HARRISON,AND A. RUTENBERG'

    E-Print Network [OSTI]

    Rutenberg, Andrew

    of colloids (aerogels) (4), condensed smoke ( 3 , composite for- mation (6), or sintering of metal powder (7

  13. Axion Dark Matter Searches

    E-Print Network [OSTI]

    I. Stern

    2014-03-21

    Nearly all astrophysical and cosmological data point convincingly to a large component of cold dark matter in the Universe. The axion particle, first theorized as a solution to the strong charge-parity problem of quantum chromodynamics, has been established as a prominent CDM candidate. Cosmic observation and particle physics experiments have bracketed the unknown mass of the axion between approximately a $\\mu$eV and a meV. The Axion Dark Matter eXperiement (ADMX) has successfully completed searches between 1.9 and 3.7 $\\mu$eV down to the KSVZ photon-coupling limit. ADMX and the Axion Dark Matter eXperiement High-Frequency (ADMX-HF) will search for axions at weaker coupling and/or higher frequencies within the next few years. Status of the experiments, current research and development, and projected mass-coupling exclusion limits are presented.

  14. Axion Dark Matter Searches

    E-Print Network [OSTI]

    Stern, I

    2014-01-01

    Nearly all astrophysical and cosmological data point convincingly to a large component of cold dark matter in the Universe. The axion particle, first theorized as a solution to the strong charge-parity problem of quantum chromodynamics, has been established as a prominent CDM candidate. Cosmic observation and particle physics experiments have bracketed the unknown mass of the axion between approximately a $\\mu$eV and a meV. The Axion Dark Matter eXperiement (ADMX) has successfully completed searches between 1.9 and 3.7 $\\mu$eV down to the KSVZ photon-coupling limit. ADMX and the Axion Dark Matter eXperiement High-Frequency (ADMX-HF) will search for axions at weaker coupling and/or higher frequencies within the next few years. Status of the experiments, current research and development, and projected mass-coupling exclusion limits are presented.

  15. Thermodynamics of clusterized matter

    E-Print Network [OSTI]

    Ad. R. Raduta; F. Gulminelli

    2009-08-26

    Thermodynamics of clusterized matter is studied in the framework of statistical models with non-interacting cluster degrees of freedom. At variance with the analytical Fisher model, exact Metropolis simulation results indicate that the transition from homogeneous to clusterized matter lies along the $\\rho=\\rho_0$ axis at all temperatures and the limiting point of the phase diagram is not a critical point even if the surface energy vanishes at this point. Sensitivity of the inferred phase diagram to the employed statistical framework in the case of finite systems is discussed by considering the grand-canonical and constant-pressure canonical ensembles. A Wigner-Seitz formalism in which the fragment charge is neutralized by an uniform electron distribution allows to build the phase diagram of neutron star matter.

  16. Natural minimal dark matter

    E-Print Network [OSTI]

    Fabbrichesi, Marco

    2015-01-01

    We show how the Higgs boson mass is protected from the potentially large corrections due to the introduction of minimal dark matter if the new physics sector is made supersymmetric. The fermionic dark matter candidate (a 5-plet of $SU(2)_L$) is accompanied by a scalar state. The weak gauge sector is made supersymmetric and the Higgs boson is embedded in a supersymmetric multiplet. The remaining standard model states are non-supersymmetric. Non vanishing corrections to the Higgs boson mass only appear at three-loop level and the model is natural for dark matter masses up to 15 TeV--a value larger than the one required by the cosmological relic density. The construction presented stands as an example of a general approach to naturalness that solves the little hierarchy problem which arises when new physics is added beyond the standard model at an energy scale around 10 TeV.

  17. Axion Dark Matter Searches

    E-Print Network [OSTI]

    I. Stern

    2015-11-17

    Nearly all astrophysical and cosmological data point convincingly to a large component of cold dark matter in the Universe. The axion particle, first theorized as a solution to the strong charge-parity problem of quantum chromodynamics, has been established as a prominent CDM candidate. Cosmic observation and particle physics experiments have bracketed the unknown mass of the axion between approximately a $\\mu$eV and a meV. The Axion Dark Matter eXperiement (ADMX) has successfully completed searches between 1.9 and 3.7 $\\mu$eV down to the KSVZ photon-coupling limit. ADMX and the Axion Dark Matter eXperiement High-Frequency (ADMX-HF) will search for axions at weaker coupling and/or higher frequencies within the next few years. Status of the experiments, current research and development, and projected mass-coupling exclusion limits are presented.

  18. Cold nuclear matter

    E-Print Network [OSTI]

    C. O. Dorso; P. A. Giménez Molinelli; J. I. Nichols; J. A. López

    2013-05-09

    The behavior of nuclear matter is studied at low densities and temperatures using classical molecular dynamics with three different sets of potentials with different compressibility. Nuclear matter is found to arrange in crystalline structures around the saturation density and in non-homogeneous (i.e. pasta-like) structures at lower densities. Similar results were obtained with a simple Lennard-Jones potential. Finite size effects are analysed and the existence of the non-homogeneous structures is shown to be inherent to the use of periodic boundary conditions and the finitude of the system. For large enough systems the non-homogeneous structures are limited to one sphere, one rod or one slab per simulation cell, which are shown to be minimal surface structures under cubic periodic boundary conditions at the corresponding volume fraction. The relevance of these findings to the simulations of neutron star and supernovae matter is discussed.

  19. Asymptotically Safe Dark Matter

    E-Print Network [OSTI]

    Francesco Sannino; Ian M. Shoemaker

    2015-08-05

    We introduce a new paradigm for dark matter (DM) interactions in which the interaction strength is asymptotically safe. In models of this type, the coupling strength is small at low energies but increases at higher energies, and asymptotically approaches a finite constant value. The resulting phenomenology of this "asymptotically safe DM" is quite distinct. One interesting effect of this is to partially offset the low-energy constraints from direct detection experiments without affecting thermal freeze-out processes which occur at higher energies. High-energy collider and indirect annihilation searches are the primary ways to constrain or discover asymptotically safe dark matter.

  20. Safe Dark Matter

    E-Print Network [OSTI]

    Francesco Sannino; Ian M. Shoemaker

    2015-07-29

    We introduce a new paradigm for dark matter (DM) interactions in which the interaction strength is asymptotically safe. In models of this type, the coupling strength is small at low energies but increases at higher energies, and asymptotically approaches a finite constant value. The resulting phenomenology of this "safe DM" is quite distinct. One interesting effect of this is to partially offset the low-energy constraints from direct detection experiments without affecting thermal freeze-out processes which occur at higher energies. High-energy collider and indirect annihilation searches are the primary ways to constrain or discover safe dark matter.

  1. USDA Forest Service Gen. Tech. Rep. PSW-GTR-193. 2004. 93 Linking Vegetation Patterns to Potential Smoke

    E-Print Network [OSTI]

    to compare fuel loading, modeled fuel consumption, smoke production, fire behavior, and susceptibility and Alvarado USDA Forest Service Gen. Tech. Rep. PSW-GTR-193. 2004.94 consumption, smoke production, fire Smoke Production and Fire Hazard1 Roger D. Ottmar2 and Ernesto Alvarado3 During the past 80 years

  2. Chemical and carbon isotopic characteristics of ash and smoke derived from burning of C3 and C4 grasses

    E-Print Network [OSTI]

    Chemical and carbon isotopic characteristics of ash and smoke derived from burning of C3 and C4 material and corresponding ash and smoke pro- duced from burning. The results show that smoke produced from C depletion varies with species from Ash derived from C4 grasses is

  3. Lithium Wall Conditioning And Surface Dust Detection On NSTX

    SciTech Connect (OSTI)

    Skinner, C H; Bell, M G; Friesen, F.Q.L.; Heim, B; Jaworski, M A; Kugel, H; Maingi, R; Rais, B

    2011-05-23

    Lithium evaporation onto NSTX plasma facing components (PFC) has resulted in improved energy confinement, and reductions in the number and amplitude of edge-localized modes (ELMs) up to the point of complete ELM suppression. The associated PFC surface chemistry has been investigated with a novel plasma material interface probe connected to an in-vacuo surface analysis station. Analysis has demonstrated that binding of D atoms to the polycrystalline graphite material of the PFCs is fundamentally changed by lithium - in particular deuterium atoms become weakly bonded near lithium atoms themselves bound to either oxygen or the carbon from the underlying material. Surface dust inside NSTX has been detected in real-time using a highly sensitive electrostatic dust detector. In a separate experiment, electrostatic removal of dust via three concentric spiral-shaped electrodes covered by a dielectric and driven by a high voltage 3-phase waveform was evaluated for potential application to fusion reactors

  4. Origin of Interplanetary Dust through Optical Properties of Zodiacal Light

    E-Print Network [OSTI]

    Yang, Hongu

    2015-01-01

    This study investigates the origin of interplanetary dust particles (IDPs) through the optical properties, albedo and spectral gradient, of zodiacal light. The optical properties were compared with those of potential parent bodies in the solar system, which include D-type (as analogue of cometary nuclei), C-type, S-type, X-type, and B-type asteroids. We applied Bayesian inference on the mixture model made from the distribution of these sources, and found that >90% of the interplanetary dust particles originate from comets (or its spectral analogues, D-type asteroids). Although some classes of asteroids (C-type and X-type) may make a moderate contribution, ordinary chondrite-like particles from S-type asteroids occupy a negligible fraction of the interplanetary dust cloud complex. The overall optical properties of the zodiacal light were similar to those of chondritic porous IDPs, supporting the dominance of cometary particles in zodiacal cloud.

  5. Dust size distribution and concentrations with cottonseed oil mills 

    E-Print Network [OSTI]

    Wiederhold, Lee Roy

    1976-01-01

    -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...

  6. Testing your home for lead in paint, dust, and soil

    SciTech Connect (OSTI)

    1998-10-01

    This publication is for anyone who is considering having a home or residence tested for lead in paint, dust, or soil by a professional. It explains the technical aspects of lead testing without overwhelming the reader. The first section tells why you would test for lead, the approaches for testing for lead, and what information you will get from each approach. The second section answers specific questions about how paint, soil, and dust sampling are conducted by the professional in your home. Finally, the last section answers other questions about testing, including questions about home test kits and testing of water and ceramics.

  7. Quantum Condensed Matter | Neutron Science | ORNL

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

    Quantum Condensed Matter SHARE Quantum Condensed Matter Neutron scattering is a uniquely powerful probe for measuring the structure and dynamics of condensed matter. As such it is...

  8. Quantum Condensed Matter | More Science | ORNL

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

    Quantum Condensed Matter SHARE Quantum Condensed Matter Neutron scattering is a uniquely powerful probe for measuring the structure and dynamics of condensed matter. As such it is...

  9. Investigation of Direct Injection Vehicle Particulate Matter...

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

    Direct Injection Vehicle Particulate Matter Emissions Investigation of Direct Injection Vehicle Particulate Matter Emissions This study focuses primarily on particulate matter mass...

  10. Asymmetric condensed dark matter

    E-Print Network [OSTI]

    Aguirre, Anthony

    2015-01-01

    We explore the viability of a boson dark matter candidate with an asymmetry between the number densities of particles and antiparticles. A simple thermal field theory analysis confirms that, under certain general conditions, this component would develop a Bose-Einstein condensate in the early universe that, for appropriate model parameters, could survive the ensuing cosmological evolution until now. The condensation of a dark matter component in equilibrium with the thermal plasma is a relativistic process, hence the amount of matter dictated by the charge asymmetry is complemented by a hot relic density frozen out at the time of decoupling. Contrary to the case of ordinary WIMPs, dark matter particles in a condensate can be very light, $10^{-22}\\,{\\rm eV} \\lesssim m \\lesssim 10^2\\,{\\rm eV}$; the lower limit arises from constraints on small-scale structure formation, while the upper bound ensures that the density from thermal relics is not too large. Big-Bang nucleosynthesis constrains the temperature of deco...

  11. Tunguska Dark Matter Ball

    E-Print Network [OSTI]

    C. D. Froggatt; H. B. Nielsen

    2015-05-10

    It is suggested that the Tunguska event in June 1908 cm-large was due to a cm-large ball of a condensate of bound states of 6 top and 6 anti-top quarks containing highly compressed ordinary matter. Such balls are supposed to make up the dark matter as we earlier proposed. The expected rate of impact of this kind of dark matter ball with the earth seems to crudely match a time scale of 200 years between the impacts. The main explosion of the Tunguska event is explained in our picture as material coming out from deep within the earth, where it has been heated and compressed by the ball penetrating to a depth of several thousand km. Thus the effect has some similarity with volcanic activity as suggested by Kundt. We discuss the possible identification of kimberlite pipes with earlier Tunguska-like events. A discussion of how the dark matter balls may have formed in the early universe is also given.

  12. Energy Matters - Spring 2002

    SciTech Connect (OSTI)

    2002-03-01

    Quarterly newsletter from DOE's Industrial Technologies Program to promote the use of energy-efficient industrial systems. The focus of the Spring 2002 Issue of Energy Matters focuses on premium energy efficiency systems, with articles on new gas technologies, steam efficiency, the Augusta Newsprint Showcase, and more.

  13. Energy Matters - Fall 2002

    SciTech Connect (OSTI)

    2002-09-01

    Quarterly newsletter from DOE's Industrial Technologies Program to promote the use of energy-efficient industrial systems. This issue focus of this edition of the Energy Matters Newsletter is on energy and environmental issues. Read more about compressed air's role in productivity, making good motor decisions, and more.

  14. Subject Matters Introduction

    E-Print Network [OSTI]

    Subject Matters Introduction The AS and A Level subject choices you make when in Year 11 (or assessing applicants at the University of Cambridge, we consider not only the individual A Level subjects taken but also the combination of these. We generally prefer applicants to have taken certain subjects

  15. Matter & Energy Solar Energy

    E-Print Network [OSTI]

    Rogers, John A.

    See Also: Matter & Energy Solar Energy· Electronics· Materials Science· Earth & Climate Energy at the University of Illinois, the future of solar energy just got brighter. Although silicon is the industry Electronics Over 1.2 Million Electronics Parts, Components and Equipment. www.AlliedElec.com solar energy

  16. Dark Matter Searches

    E-Print Network [OSTI]

    Laura Baudis

    2005-11-29

    More than 90% of matter in the Universe could be composed of heavy particles, which were non-relativistic, or 'cold', when they froze-out from the primordial soup. I will review current searches for these hypothetical particles, both via interactions with nuclei in deep underground detectors, and via the observation of their annihilation products in the Sun, galactic halo and galactic center.

  17. A Comparison of "Total Dust" and Inhalable Personal Sampling for Beryllium Exposure.

    SciTech Connect (OSTI)

    Carter, C M

    2012-04-25

    In 2009, the American Conference of Governmental Industrial Hygienists (ACGIH) reduced the Beryllium (Be) 8-hr Time Weighted Average Threshold Limit Value (TLV-TWA) from 2.0 {micro}g/m{sup 3} to 0.05 {micro}g/m{sup 3} with an inhalable 'I' designation in accordance with ACGIH's particle size-selective criterion for inhalable mass. Currently, per the Department of Energy (DOE) requirements, the Lawrence Livermore National Laboratory (LLNL) is following the Occupational Health and Safety Administration (OSHA) Permissible Exposure Limit (PEL) of 2.0 {micro}g/m{sup 3} as an 8-hr TWA, which is also the 2005 ACGIH TLV-TWA, and an Action Level (AL) of 0.2 {micro}g/m{sup 3} and sampling is performed using the 37mm (total dust) sampling method. Since DOE is considering adopting the newer 2009 TLV guidelines, the goal of this study was to determine if the current method of sampling using the 37mm (total dust) sampler would produce results that are comparable to what would be measured using the IOM (inhalable) sampler specific to the application of high energy explosive work at LLNL's remote experimental test facility at Site 300. Side-by-side personal sampling using the two samplers was performed over an approximately two-week period during chamber re-entry and cleanup procedures following detonation of an explosive assembly containing Beryllium (Be). The average ratio of personal sampling results for the IOM (inhalable) vs. 37-mm (total dust) sampler was 1.1:1 with a P-value of 0.62, indicating that there was no statistically significant difference in the performance of the two samplers. Therefore, for the type of activity monitored during this study, the 37-mm sampling cassette would be considered a suitable alternative to the IOM sampler for collecting inhalable particulate matter, which is important given the many practical and economic advantages that it presents. However, similar comparison studies would be necessary for this conclusion to be applied to other types of activities, where earlier studies have shown that the IOM sampler tends to collect higher concentrations of Be compared to the 37-mm cassette, which could complicate compliance with what is already an extremely low exposure limit.

  18. The Development of Measurement Techniques to Identify and Characterize Dusts and Ice Nuclei in the Atmosphere 

    E-Print Network [OSTI]

    Glen, Andrew

    2014-01-15

    Mineral dusts and ice crystals directly influence the Earth's radiative budget through radiative scattering and absorption. The interaction of spherical particles on the radiative budget are well known, however mineral dusts and ice crystals...

  19. A New Facility for Studying Shock Wave Passage over Dust Layers 

    E-Print Network [OSTI]

    Marks, Brandon

    2013-05-30

    To ensure safety regarding dust explosion hazards, it is important to study the dust lifting process experimentally and identify important parameters that will be valuable for development and validation of numerical predictions of this phenomenon. A...

  20. Integrated impact analysis of yellow-dust storms : a regional case study in China

    E-Print Network [OSTI]

    Ai, Ning, 1978-

    2003-01-01

    The dust storm is a meteorological event that is caused by strong winds and proceeds from arid and semi-arid regions, transporting a thick cloud of fine sediments. In China, the sediments of dust storms mainly come from ...

  1. Effect of argon addition on plasma parameters and dust charging in hydrogen plasma

    SciTech Connect (OSTI)

    Kakati, B. Kausik, S. S.; Saikia, B. K.; Bandyopadhyay, M.; Saxena, Y. C.

    2014-10-28

    Experimental results on effect of adding argon gas to hydrogen plasma in a multi-cusp dusty plasma device are reported. Addition of argon modifies plasma density, electron temperature, degree of hydrogen dissociation, dust current as well as dust charge. From the dust charging profile, it is observed that the dust current and dust charge decrease significantly up to 40% addition of argon flow rate in hydrogen plasma. But beyond 40% of argon flow rate, the changes in dust current and dust charge are insignificant. Results show that the addition of argon to hydrogen plasma in a dusty plasma device can be used as a tool to control the dust charging in a low pressure dusty plasma.

  2. Mineral content analysis of atmospheric dust using hyperspectral information from space

    E-Print Network [OSTI]

    Kostinski, Alex

    Mineral content analysis of atmospheric dust using hyperspectral information from space A one of the world's largest sources of atmospheric mineral dust. Mineral composition optical properties, and mineral deposition to Amazon forests. In this study we examine hyperspectral

  3. What controls the recent changes in African mineral dust aerosol across the Atlantic?

    E-Print Network [OSTI]

    Ridley, David Andrew

    Dust from Africa strongly perturbs the radiative balance over the Atlantic, with emissions that are highly variable from year to year. We show that the aerosol optical depth (AOD) of dust over the mid-Atlantic observed by ...

  4. Techniques For Injection Of Pre-Charaterized Dust Into The Scrape...

    Office of Scientific and Technical Information (OSTI)

    For Injection Of Pre-Charaterized Dust Into The Scrape Off Layer Of Fusion Plasma Introduction of micron-sized dust into the scrape-off layer (SOL) of a plasma has recently...

  5. Engineering and economic impacts of prohibiting recombination recirculation dust at export elevators 

    E-Print Network [OSTI]

    Whitelock, Derek Paul

    1994-01-01

    The objectives of this research were to develop engineering descriptions of dust control systems currently being used in grain export facilities, to determine the retrofit requirements of the dust control and handling ...

  6. deep highresolution optical log dust, ash, and stratigraphy South Pole glacial

    E-Print Network [OSTI]

    Woschnagg, Kurt

    deep high­resolution optical log dust, ash, and stratigraphy South Pole glacial Bramall, Bay, Rohde, Price (2005), high­resolution optical dust, stratigraphy South Pole glacial Geophys. Res. Lett

  7. Energy Matters in Washington State Page 1 Energy Matters

    E-Print Network [OSTI]

    Collins, Gary S.

    Energy Matters in Washington State ­ Page 1 Energy Matters in Washington State June 2008 Updated November 2009 Updated and Revised October 2013 Grand Coulee Dam #12;Energy Matters in Washington State ­ Page 2 Copyright © 2013 Washington State University Energy Program. 905 Plum Street SE, P.O. Box 43169

  8. Observations of heterogeneous reactions between Asian pollution and mineral dust over the Eastern North Pacific during INTEX-B

    E-Print Network [OSTI]

    2009-01-01

    light scattering, due to competition between pollution andAsian pollution and mineral dust Table 8. Changes to lightpollution and mineral dust Table 6. Comparison of light

  9. A GCM investigation of dust aerosol impact on the regional climate of North Africa and South/East Asia

    E-Print Network [OSTI]

    Gu, Y; Xue, Y; de Sales, F; Liou, KN

    2015-01-01

    Chem suggested that whether aero- sols enhance or suppresssemi-arid region. Dust aero- sols also appear in Australiaresults that the dust aero- sol effects on precipitation

  10. The Search for Dark Matter

    SciTech Connect (OSTI)

    Orrell, John

    2013-11-20

    More than 25 years ago, PNNL scientists began the first underground measurements searching for dark matter using specialized radiation detector technology. Dark matter is yet to be discovered says Physicist John L. Orrell.

  11. The Search for Dark Matter

    ScienceCinema (OSTI)

    Orrell, John

    2014-07-24

    More than 25 years ago, PNNL scientists began the first underground measurements searching for dark matter using specialized radiation detector technology. Dark matter is yet to be discovered says Physicist John L. Orrell.

  12. On the dust environment of comet C/2012 S1 (ISON) from 12 AU...

    Office of Scientific and Technical Information (OSTI)

    COSMOLOGY AND ASTRONOMY; ALFVEN WAVES; COMETS; CONFIGURATION; DENSITY; DUSTS; EMISSION; FRAGMENTATION; GALAXY NUCLEI; IMAGES; MASS; MONTE CARLO METHOD; PARTICLES; SPHERES;...

  13. Experimental quiescent drifting dusty plasmas and temporal dust acoustic wave growth

    E-Print Network [OSTI]

    Merlino, Robert L.

    Experimental quiescent drifting dusty plasmas and temporal dust acoustic wave growth J. R. Heinrich quiescent drifting dusty plasmas and temporal dust acoustic wave growth J. R. Heinrich, S.-H. Kim, J. K report on dust acoustic wave growth rate measurements taken in a dc (anode glow) discharge plasma device

  14. Nonlinear Dust Acoustic Waves, Shocks and Stationary Structures in a DC Glow Discharge Dusty Plasma

    E-Print Network [OSTI]

    Merlino, Robert L.

    Nonlinear Dust Acoustic Waves, Shocks and Stationary Structures in a DC Glow Discharge Dusty Plasma drifting dusty plasmas and temporal dust acoustic wave growth Phys. Plasmas 18, 113706 (2011) Modulational;Nonlinear Dust Acoustic Waves, Shocks and Stationary Structures in a DC Glow Discharge Dusty Plasma Robert L

  15. Mineral dust emission from the Bodele Depression, northern Chad, during BoDEx 2005

    E-Print Network [OSTI]

    Washington, Richard

    distribution of this diatomite dust estimated from sun photometer data, using a modified Aeronet retrieval loadings results in a reduction in surface daytime maximum temperature of around 7°C in the Bode´le´ region-blown terrestrial mineral dust. The distribution, properties of mineral dust and its climate impact are poorly

  16. Saharan mineral dust transport into the Caribbean: Observed atmospheric controls and trends

    E-Print Network [OSTI]

    Hameed, Sultan

    Saharan mineral dust transport into the Caribbean: Observed atmospheric controls and trends O. M December 2007; published 15 April 2008. [1] Each summer large amounts of mineral dust from the Sahara in this region. In this paper we analyze summer season interannual variability of North African mineral dust over

  17. SAVE THIS | EMAIL THIS | Close 'Smart dust' aims to monitor everything

    E-Print Network [OSTI]

    Lu, Chenyang

    distinguisher, too. A building's thermostat is most likely hard-wired. A smart dust sensor might gaugePowered by SAVE THIS | EMAIL THIS | Close 'Smart dust' aims to monitor everything By John D. Sutter, CNN STORY HIGHLIGHTS 'Smart dust' refers to tiny sensors that would monitor everything on Earth

  18. Gas and dust in the star-forming region rho Oph A: The dust opacity exponent beta and the gas-to-dust mass ratio g2d

    E-Print Network [OSTI]

    Liseau, R; Lunttila, T; Olberg, M; Rydbeck, G; Bergman, P; Justtanont, K; Olofsson, G; de Vries, B L

    2015-01-01

    We aim at determining the spatial distribution of the gas and dust in star-forming regions and address their relative abundances in quantitative terms. We also examine the dust opacity exponent beta for spatial and/or temporal variations. Using mapping observations of the very dense rho Oph A core, we examined standard 1D and non-standard 3D methods to analyse data of far-infrared and submillimeter (submm) continuum radiation. The resulting dust surface density distribution can be compared to that of the gas. The latter was derived from the analysis of accompanying molecular line emission, observed with Herschel from space and with APEX from the ground. As a gas tracer we used N2H+, which is believed to be much less sensitive to freeze-out than CO and its isotopologues. Radiative transfer modelling of the N2H+(J=3-2) and (J=6-5) lines with their hyperfine structure explicitly taken into account provides solutions for the spatial distribution of the column density N(H2), hence the surface density distribution ...

  19. Proxies and Measurement Techniques for Mineral Dust in

    E-Print Network [OSTI]

    Fischer, Hubertus

    concentrations, which are typically a factor 100, differ between the methods by up to a factor of 2Proxies and Measurement Techniques for Mineral Dust in Antarctic Ice Cores U R S R U T H , * , C, Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Denmark, Department

  20. Global observations and spectral characteristics of desert dust and

    E-Print Network [OSTI]

    Graaf, Martin de

    characteristics of desert dust and biomass burning scenes · Conclusions and Outlook #12;where Rayleigh R340 Doubling-Adding KNMI Radiative Transfer Model Solar zenith angle = 30° Viewing zenith angle = 0° Surface Model Solar zenith angle = 30° Viewing zenith angle = 0° Surface albedo = 5% Absorbing aerosols

  1. Global observations of desert dust and biomass burning aerosols

    E-Print Network [OSTI]

    Graaf, Martin de

    and desert dust observations from GOME and SCIAMACHY · Conclusions and Outlook #12; · Absorbing Aerosol Transfer Model Solar zenith angle = 30° Viewing zenith angle = 0° Surface albedo = 5% #12;Reflectance at TOA with absorbing aerosols Doubling-Adding KNMI Radiative Transfer Model Solar zenith angle = 30

  2. Dust Cooling in Supernova Remnants in the Large Magellanic Cloud

    E-Print Network [OSTI]

    Seok, Ji Yeon; Hirashita, Hiroyuki

    2015-01-01

    The infrared-to-X-ray (IRX) flux ratio traces the relative importance of dust cooling to gas cooling in astrophysical plasma such as supernova remnants (SNRs). We derive IRX ratios of SNRs in the LMC using Spitzer and Chandra SNR survey data and compare them with those of Galactic SNRs. IRX ratios of all the SNRs in the sample are found to be moderately greater than unity, indicating that dust grains are a more efficient coolant than gas although gas cooling may not be negligible. The IRX ratios of the LMC SNRs are systematically lower than those of the Galactic SNRs. As both dust cooling and gas cooling pertain to the properties of the interstellar medium, the lower IRX ratios of the LMC SNRs may reflect the characteristics of the LMC, and the lower dust-to- gas ratio (a quarter of the Galactic value) is likely to be the most significant factor. The observed IRX ratios are compared with theoretical predictions that yield IRX ratios an order of magnitude larger. This discrepancy may originate from the dearth ...

  3. WEATHER MODIFICATION BY CARBON DUST ABSORPTION OF SOLAR ENERGY

    E-Print Network [OSTI]

    Gray, William

    WEATHER MODIFICATION BY CARBON DUST ABSORPTION OF SOLAR ENERGY by WM. M. GRAY, WM. M. FRANK, M OF SOLAR ENERGY by w. M. Gray, W. M. Frank, M. L. Corrin and C. A. Stokes Department of Atmospheric Science interception of solar energy. Growing population pressures and predicted future global food shortages dictate

  4. Friday, March 27, 2009 MARS: DUNES, DUST, AND WIND

    E-Print Network [OSTI]

    Rathbun, Julie A.

    Friday, March 27, 2009 MARS: DUNES, DUST, AND WIND 8:30 a.m. Waterway Ballroom 1 Chairs: Lori Fenton Steve Metzger 8:30 a.m. Chojnacki M. * Moersch J. E. Valles Marineris Dune Fields: Thermophysical Properties, Morphology, and Provenance [#2486] We examined 25 dune fields in Valles Marineris to identify

  5. ORIGINAL PAPER Relationship between African dust carried in the Atlantic

    E-Print Network [OSTI]

    Prospero, Joseph M.

    the daily concentrations of dust measured in on-shore Trade Winds at Barbados and pediatric asthma Scott Polyclinic, Queen Elizabeth Hospital, Barbados, West Indies R. Naidu :H. Thani Faculty of Medical Sciences, The University of the West Indies, Cave Hill Campus, Barbados, West Indies R. Naidu :H. Thani

  6. The metal and dust yields of the first massive stars

    E-Print Network [OSTI]

    Marassi, S; Limongi, M; Chieffi, A; Bocchio, M; Bianchi, S

    2015-01-01

    We quantify the role of Population (Pop) III core-collapse supernovae (SNe) as the first cosmic dust polluters. Starting from a homogeneous set of stellar progenitors with masses in the range [13 - 80] Msun, we find that the mass and composition of newly formed dust depend on the mixing efficiency of the ejecta and the degree of fallback experienced during the explosion. For standard Pop III SNe, whose explosions are calibrated to reproduce the average elemental abundances of Galactic halo stars with [Fe/H] < -2.5, between 0.18 and 3.1 Msun (0.39 - 1.76 Msun) of dust can form in uniformly mixed (unmixed) ejecta, and the dominant grain species are silicates. We also investigate dust formation in the ejecta of faint Pop III SN, where the ejecta experience a strong fallback. By examining a set of models, tailored to minimize the scatter with the abundances of carbon-enhanced Galactic halo stars with [Fe/H ] < -4, we find that amorphous carbon is the only grain species that forms, with masses in the range 2...

  7. The Influence of Dust on the Absorptivity of Radiant Barriers 

    E-Print Network [OSTI]

    Noboa, Homero L.

    1993-01-01

    The purpose of this project was to model and quantify the increase of the absorptivity of radiant barriers caused by the accumulation of dust on the surface of radiant barriers. This research was the continuation of a previous work by the author...

  8. Dust Aerosol Important for Snowball Earth Deglaciation DORIAN S. ABBOT

    E-Print Network [OSTI]

    Halevy, Itay

    December 2009) ABSTRACT Most previous global climate model simulations could only produce the termination of Snowball Earth episodes at CO2 partial pressures of several tenths of a bar, which is roughly an order in the partial pressure of CO2 from 1024 to 1021 bar. Therefore the conclusion is reached that including dust

  9. Magnetic field modulated dust streams from Jupiter in Interplanetary space

    E-Print Network [OSTI]

    Hamilton, Douglas P.

    Magnetic field modulated dust streams from Jupiter in Interplanetary space Alberto Flandes Ciencias´es-Galicia Ciencias Espaciales, Instituto de Geof´isica, UNAM, M´exico. Linda Spilker Jet Propulsion Laboratory is sufficient to allow the planet's magnetic field to accelerate them away from the planet where

  10. Levitating Dark Matter

    E-Print Network [OSTI]

    Nemanja Kaloper; Antonio Padilla

    2009-10-07

    A sizable fraction of the total energy density of the universe may be in heavy particles with a net dark $U(1)'$ charge comparable to its mass. When the charges have the same sign the cancellation between their gravitational and gauge forces may lead to a mismatch between different measures of masses in the universe. Measuring galactic masses by orbits of normal matter, such as galaxy rotation curves or lensing, will give the total mass, while the flows of dark matter agglomerates may yield smaller values if the gauge repulsion is not accounted for. If distant galaxies which house light beacons like SNe Ia contain such dark particles, the observations of their cosmic recession may mistake the weaker forces for an extra `antigravity', and infer an effective dark energy equation of state smaller than the real one. In some cases, including that of a cosmological constant, these effects can mimic $wdark energy, or superhorizon effects.

  11. Rigid particulate matter sensor

    DOE Patents [OSTI]

    Hall, Matthew (Austin, TX)

    2011-02-22

    A sensor to detect particulate matter. The sensor includes a first rigid tube, a second rigid tube, a detection surface electrode, and a bias surface electrode. The second rigid tube is mounted substantially parallel to the first rigid tube. The detection surface electrode is disposed on an outer surface of the first rigid tube. The detection surface electrode is disposed to face the second rigid tube. The bias surface electrode is disposed on an outer surface of the second rigid tube. The bias surface electrode is disposed to face the detection surface electrode on the first rigid tube. An air gap exists between the detection surface electrode and the bias surface electrode to allow particulate matter within an exhaust stream to flow between the detection and bias surface electrodes.

  12. Self-Interacting Dark Matter

    E-Print Network [OSTI]

    Benjamin D. Wandelt; Romeel Dave; Glennys R. Farrar; Patrick C. McGuire; David N. Spergel; Paul J. Steinhardt

    2000-06-28

    Spergel and Steinhardt have recently proposed the concept of dark matter with strong self-interactions as a means to address numerous discrepancies between observations of dark matter halos on subgalactic scales and the predictions of the standard collisionless dark matter picture. We review the motivations for this scenario and discuss some recent, successful numerical tests. We also discuss the possibility that the dark matter interacts strongly with ordinary baryonic matter, as well as with itself. We present a new analysis of the experimental constraints and re-evaluate the allowed range of cross-section and mass.

  13. Cadmium, lead and mercury exposure in non smoking pregnant women

    SciTech Connect (OSTI)

    Hinwood, A.L., E-mail: a.hinwood@ecu.edu.au [Centre for Ecosystem Management, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027 (Australia); Callan, A.C.; Ramalingam, M.; Boyce, M. [Centre for Ecosystem Management, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027 (Australia)] [Centre for Ecosystem Management, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027 (Australia); Heyworth, J. [School Population Health, The University of Western Australia, 35 Stirling Highway Crawley, WA 6009 (Australia)] [School Population Health, The University of Western Australia, 35 Stirling Highway Crawley, WA 6009 (Australia); McCafferty, P. [ChemCentre, PO Box 1250, Bentley, WA 6983 (Australia)] [ChemCentre, PO Box 1250, Bentley, WA 6983 (Australia); Odland, J.Ø. [Department of Community Medicine, University of Tromsø, N-9037 Tromsø (Norway)] [Department of Community Medicine, University of Tromsø, N-9037 Tromsø (Norway)

    2013-10-15

    Recent literature suggests that exposure to low concentrations of heavy metals may affect both maternal and child health. This study aimed to determine the biological heavy metals concentrations of pregnant women as well as environmental and dietary factors that may influence exposure concentrations. One hundred and seventy three pregnant women were recruited from Western Australia, each providing a sample of blood, first morning void urine, residential soil, dust and drinking water samples. Participants also completed a questionnaire which included a food frequency component. All biological and environmental samples were analysed for heavy metals using ICP-MS. Biological and environmental concentrations of lead and mercury were generally low (Median Pb Drinking Water (DW) 0.04 µg/L; Pb soil <3.0 µg/g; Pb dust 16.5 µg/g; Pb blood 3.67 µg/L; Pb urine 0.55; µg/L Hg DW <0.03; Hg soil <1.0 µg/g; Hg dust <1.0 µg/g; Hg blood 0.46 µg/L; Hg urine <0.40 µg/L). Cadmium concentrations were low in environmental samples (Median CdDW 0.02 µg/L; Cdsoil <0.30 ug/g; Cddust <0.30) but elevated in urine samples (Median 0.55 µg/L, creatinine corrected 0.70 µg/g (range <0.2–7.06 µg/g creatinine) compared with other studies of pregnant women. Predictors of increased biological metals concentrations in regression models for blood cadmium were residing in the Great Southern region of Western Australia and not using iron/folic acid supplements and for urinary cadmium was having lower household annual income. However, these factors explained little of the variation in respective biological metals concentrations. The importance of establishing factors that influence low human exposure concentrations is becoming critical in efforts to reduce exposures and hence the potential for adverse health effects. -- Highlights: • Biological heavy metals concentrations in women in their 3rd trimester of pregnancy. • Exposure assessment including environmental, lifestyle and activity data. • Urinary cadmium concentrations were elevated in this group of pregnant women. • Blood lead and mercury concentrations were below recommended biological guideline values.

  14. Hidden vector dark matter

    E-Print Network [OSTI]

    Thomas Hambye

    2010-03-16

    We show that dark matter could be made of massive gauge bosons whose stability doesn't require to impose by hand any discrete or global symmetry. Stability of gauge bosons can be guaranteed by the custodial symmetry associated to the gauge symmetry and particle content of the model. The particle content we consider to this end is based on a hidden sector made of a vector multiplet associated to a non-abelian gauge group and of a scalar multiplet charged under this gauge group. The hidden sector interacts with the Standard Model particles through the Higgs portal quartic scalar interaction in such a way that the gauge bosons behave as thermal WIMPS. This can lead easily to the observed dark matter relic density in agreement with the other various constraints, and can be tested experimentally in a large fraction of the parameter space. In this model the dark matter direct detection rate and the annihilation cross section can decouple if the Higgs portal interaction is weak.

  15. Cosmology with matter diffusion

    SciTech Connect (OSTI)

    Calogero, Simone; Velten, Hermano E-mail: velten@cce.ufes.br

    2013-11-01

    We construct a viable cosmological model based on velocity diffusion of matter particles. In order to ensure the conservation of the total energy-momentum tensor in the presence of diffusion, we include a cosmological scalar field ? which we identify with the dark energy component of the universe. The model is characterized by only one new degree of freedom, the diffusion parameter ?. The standard ?CDM model can be recovered by setting ? = 0. If diffusion takes place (? > 0) the dynamics of the matter and of the dark energy fields are coupled. We argue that the existence of a diffusion mechanism in the universe may serve as a theoretical motivation for interacting models. We constrain the background dynamics of the diffusion model with Supernovae, H(z) and BAO data. We also perform a perturbative analysis of this model in order to understand structure formation in the universe. We calculate the impact of diffusion both on the CMB spectrum, with particular attention to the integrated Sachs-Wolfe signal, and on the matter power spectrum P(k). The latter analysis places strong constraints on the magnitude of the diffusion mechanism but does not rule out the model.

  16. A NEW VIEW ON INTERSTELLAR DUST HIGH FIDELITY STUDIES OF INTERSTELLAR DUST ANALOGUE TRACKS IN STARDUST FLIGHT SPARE AEROGEL

    E-Print Network [OSTI]

    IN STARDUST FLIGHT SPARE AEROGEL F. Postberg, C. Allen, S. Bajt, H. A. Bechtel, J. Borg, F. Brenker, J the Stardust Mission exposed aerogel collector panels for a total of about 200 days to the stream - 30km/s] interstellar dust (ISD) analogues onto Stardust aerogel flight spares. This en- ables

  17. 16 years of Ulysses Interstellar Dust Measurements in the Solar System: II. Fluctuations in the Dust Flow from the Data

    E-Print Network [OSTI]

    Strub, Peter; Sterken, Veerle J

    2015-01-01

    The Ulysses spacecraft provided the first opportunity to identify and study Interstellar Dust (ISD) in-situ in the Solar System between 1992 and 2007. Here we present the first comprehensive analysis of the ISD component in the entire Ulysses dust data set. We analysed several parameters of the ISD flow in a time-resolved fashion: flux, flow direction, mass index, and flow width. The general picture is in agreement with a time-dependent focussing/defocussing of the charged dust particles due to long-term variations of the solar magnetic field throughout a solar magnetic cycle of 22 years. In addition, we confirm a shift in dust direction of $50^{\\circ} \\pm 7^{\\circ}$ in 2005, along with a steep, size-dependent increase in flux by a factor of 4 within 8 months. To date, this is difficult to interpret and has to be examined in more detail by new dynamical simulations. This work is part of a series of three papers. This paper concentrates on the time-dependent flux and direction of the ISD. In a companion paper ...

  18. Method and apparatus for measuring surface density of explosive and inert dust in stratified layers

    DOE Patents [OSTI]

    Sapko, Michael J. (Finleyville, PA); Perlee, Henry E. (Bethel Park, PA)

    1988-01-01

    A method for determining the surface density of coal dust on top of rock dust or rock dust on top of coal dust is disclosed which comprises directing a light source at either a coal or rock dust layer overlaying a substratum of the other, detecting the amount of light reflected from the deposit, generating a signal from the reflected light which is converted into a normalized output (V), and calculating the surface density from the normalized output. The surface density S.sub.c of coal dust on top of rock dust is calculated according to the equation: S.sub.c =1/-a.sub.c ln(V) wherein a.sub.c is a constant for the coal dust particles, and the surface density S.sub.r of rock dust on top of coal dust is determined by the equation: ##EQU1## wherein a.sub.r is a constant based on the properties of the rock dust particles. An apparatus is also disclosed for carrying out the method of the present invention.

  19. Dust Acoustic Solitons in the Dusty Plasma of the Earth's Ionosphere

    SciTech Connect (OSTI)

    Kopnin, S.I.; Kosarev, I.N.; Popel, S.I.; Yu, M.Y.

    2005-03-15

    Stratified structures that are observed at heights of 80-95 km in the lower part of the Earth's ionosphere are known as noctilucent clouds and polar mesosphere summer echoes. These structures are thought to be associated with the presence of vast amounts of charged dust or aerosols. The layers in the lower ionosphere where there are substantial amounts of dust are called the dusty ionosphere. The dust grains can carry a positive or a negative charge, depending on their constituent materials. As a rule, the grains are ice crystals, which may contain metallic inclusions. A grain with a sufficiently large metallic content can acquire a positive charge. Crystals of pure ice are charged negatively. The distribution of the dust grains over their charges has a profound impact on the ionizational and other properties of dust structures in the dusty ionosphere. In the present paper, a study is made of the effect of the sign of the dust charge on the properties of dust acoustic solitons propagating in the dusty ionosphere. It is shown that, when the dust charge is positive, dust acoustic solitons correspond to a hill in the electron density and a well in the ion density. When the dust is charged negatively, the situation is opposite. These differences in the properties of dust acoustic solitons can be used to diagnose the plasmas of noctilucent clouds and polar mesosphere summer echoes.

  20. Earth's Energy Out of Balance: The Smoking Gun for Global Warming April, 2005

    E-Print Network [OSTI]

    Hansen, James E.

    Earth's Energy Out of Balance: The Smoking Gun for Global Warming April, 2005 Scientists gun' that we have been looking for" according to Jim Hansen, a climatologist who directs the NASA

  1. FIRE /SMOKE The most effective method of fighting fires is to prevent them from occurring. All

    E-Print Network [OSTI]

    Jia, Songtao

    FIRE /SMOKE The most effective method of fighting fires is to prevent them from occurring. All-305-7979 (CUMC) after evacuating. Procedures for UNCONTROLLABLE FIRES DO NOT stay to fight a large or rapidly

  2. First-Run Smoking Presentations in U.S. Movies 1999-2006

    E-Print Network [OSTI]

    Polansky, Jonathan R.; Glantz, Stanton PhD

    2007-01-01

    Count on Me (2000) R YEAR: 1999 SMOKING OVERALL: 73% (11 ofWERE YOUTH RATED A Civil Action (1999) PG-13 (with Disney)The Out-of-Towners (1999) PG-13 Runaway Bride (1999) PG (

  3. Smoke buildup and light scattering in a cylindrical cavity above a uniform flow 

    E-Print Network [OSTI]

    Upadhyay, Rochan; Ezekoye, Ofodike

    2005-01-01

    In this study, we use computational fluid dynamics (CFD) and aerosol dynamics modeling to investigate the buildup of smoke and light scattering in a cylindrical cavity geometry, considered to be an idealized representation ...

  4. How important are metal-poor AGB stars as cosmic dust producers?

    E-Print Network [OSTI]

    Mattsson, Lars; Andersen, Anja C

    2015-01-01

    The efficiency of dust formation in oxygen-rich AGB stars should (in theory) be metallicity dependent since they are not producing their own raw material for dust production. Metal-poor carbon stars may not be very efficient dust producers either, because of more radiative heating of the grains forming in their atmospheres. We have just confirmed that inefficient dust and wind formation in simulations of metal-poor carbon stars is a real physical effect, albeit within the limitations of our simulations. Taken at face value, this implies that the amount of dust supplied by low-metallicity AGB stars to the build up of the cosmic dust component is clearly limited. Consequently, one may also ask how large a contribution AGB stars can make in general, when compared to recent observations of cosmic dust, which are suggesting major contributions from other sources?

  5. Effect of energetic electrons on dust charging in hot cathode filament discharge

    SciTech Connect (OSTI)

    Kakati, B.; 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)

    2011-03-15

    The effect of energetic electrons on dust charging for different types of dust is studied in hydrogen plasma. The hydrogen plasma is produced by hot cathode filament discharge method in a dusty plasma device. A full line cusped magnetic field cage is used to confine the plasma elements. To study the plasma parameters for various discharge conditions, a cylindrical Langmuir probe having 0.15 mm diameter and 10.0 mm length is used. An electronically controlled dust dropper is used to drop the dust particles into the plasma. For different discharge conditions, the dust current is measured using a Faraday cup connected to an electrometer. The effect of secondary emission as well as discharge voltage on charging of dust grains in hydrogen plasma is studied with different dust.

  6. 146 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 27, NO. 1, FEBRUARY 1999 Video Imaging of Dust Acoustic Waves

    E-Print Network [OSTI]

    Merlino, Robert L.

    Acoustic Waves C. Thompson, A. Barkan, R. L. Merlino, and N. D'Angelo Fig. 1. Single video frame image of a dust acoustic wave. The bright vertical bands correspond to the wave crests (dust compressions "dust waves." A sample image of a dust acoustic wave is presented. Index Terms--Image analysis, plasma

  7. A survey of spatially distributed exterior dust lead loadings in New York City

    SciTech Connect (OSTI)

    Caravanos, Jack; Weiss, Arlene L.; Blaise, Marc J.; Jaeger, Rudolph J. . E-mail: jaegerr@envmed.com

    2006-02-15

    This work documents ambient lead dust deposition values (lead loading) for the boroughs of New York City in 2003-2004. Currently, no regulatory standards exist for exterior concentrations of lead in settled dust. This is in contrast to the clearance and risk assessment standards that exist for interior residential dust. The reported potential for neurobehavioral toxicity and adverse cognitive development in children due to lead exposure prompts public health concerns about undocumented lead sources. Such sources may include settled dust of outdoor origin. Dust sampling throughout the five boroughs of NYC was done from the top horizontal portion of pedestrian traffic control signals (PTCS) at selected street intersections along main thoroughfares. The data (n=214 samples) show that lead in dust varies within each borough with Brooklyn having the highest median concentration (730{mu}g/ft{sup 2}), followed in descending order by Staten Island (452{mu}g/ft{sup 2}), the Bronx (382{mu}g/ft{sup 2}), Queens (198{mu}g/ft{sup 2}) and finally, Manhattan (175{mu}g/ft{sup 2}). When compared to the HUD/EPA indoor lead in dust standard of 40{mu}g/ft{sup 2}, our data show that this value is exceeded in 86% of the samples taken. An effort was made to determine the source of the lead in the dust atop of the PTCS. The lead in the dust and the yellow signage paint (which contains lead) were compared using isotopic ratio analysis. Results showed that the lead-based paint chip samples from intact signage did not isotopically match the dust wipe samples taken from the same surface. We know that exterior dust containing lead contributes to interior dust lead loading. Therefore, settled leaded dust in the outdoor environment poses a risk for lead exposure to children living in urban areas, namely, areas with elevated childhood blood lead levels and background lead dust levels from a variety of unidentified sources.

  8. Modelling of mineral dust for interglacial and glacial climate conditions with a focus on Antarctica

    SciTech Connect (OSTI)

    Sudarchikova, Natalia; Mikolajewicz, Uwe; Timmreck, C.; O'Donnell, D.; Schurgers, G.; Sein, Dmitry; Zhang, Kai

    2015-01-01

    Mineral dust cycle responds to insolation-induced climate change and plays an important role in the climate system by affecting the radiative balance of the atmosphere. Polar ice cores provide unique information about deposition of aeolian dust particles in the past which indicates climate variability. In the current study the dust cycle in different climate conditions simulated by ECHAM5-HAM is analyzed. The study is focused on the Southern Hemisphere with emphasis on the Antarctic region. The investigated periods include four interglacial time-slices: the pre-industrial control (CTRL), mid-Holocene (6,000 years BP), Eemian (126,000 years BP), last glacial inception (115,000 years BP) and one glacial time interval: Last Glacial Maximum (LGM) (21,000 years BP). This study is a first attempt to simulate past interglacial dust cycles and to understand the quantitative contribution of different processes, such as emission, atmospheric transport and precipitation to the total dust deposition in Antarctica. Results suggest increased deposition of mineral dust globally and in Antarctica in the past interglacial periods relative to the preindustrial CTRL simulation. Maximum dust deposition in Antarctica was simulated for the glacial period. One of the major factors responsible for the increase of dust deposition in the mid-Holocene and Eemian is enhanced Southern Hemisphere dust emissions. The moderate change of dust deposition in Antarctica in the last glacial inception period is caused by the slightly stronger poleward atmospheric transport efficiency compared to the pre-industrial. In the LGM simulation, dust deposition over Antarctica is substantially increased due to 2.6 times higher Southern Hemisphere dust emissions, 2 times stronger atmospheric transport towards Antarctica, and 30% weaker precipitation over the Southern Ocean. The model is able to reproduce the order of magnitude of dust deposition globally and in Antarctica for the pre-industrial and LGM climate. However more records are needed to validate simulated dust deposition for the past interglacial time-slices.

  9. Naked Singularities in Spherically Symmetric Inhomogeneous Tolman-Bondi Dust Cloud Collapse

    E-Print Network [OSTI]

    P. S. Joshi; I. H. Dwivedi

    1993-03-31

    We investigate the occurrence and nature of naked singularity for the inhomogeneous gravitational collapse of Tolman-Bondi dust clouds.It is shown that the naked singularities form at the center of the collapsing cloud in a wide class of collapse models which includes the earlier cases considered by Eardley and Smarr and Christodoulou. This class also contains self-similar as well as non-self-similar models. The structure and strength of this singularity is examined and the question is investigated as to when a non-zero measure set of non-spacelike trajectories could be emitted from the singularity as opposed to isolated trajectories coming out. It is seen that the weak energy condition and positivity of energy density ensures that the families of non-spacelike trajectories come out of the singularity. The curvature strength of the naked singularity is examined which provides an important test for its physical significance and powerful curvature growth near the naked singularity is pointed out for several subclasses considered. The conditions are discussed for the naked singularity to be globally naked. Implications for the basic issue of the final fate of gravitational collapse are considered once the inhomogeneities in the matter distribution are taken into account. It is argued that a physical formulation for the cosmic censorship may be evolved which avoids the features above. Possibilities in this direction are discussed while indicating that the analysis presented here should be useful for any possible rigorous formulation of the cosmic censorship hypothesis.

  10. THE IMPORTANCE OF PHYSICAL MODELS FOR DERIVING DUST MASSES AND GRAIN SIZE DISTRIBUTIONS IN SUPERNOVA EJECTA. I. RADIATIVELY HEATED DUST IN THE CRAB NEBULA

    SciTech Connect (OSTI)

    Temim, Tea; Dwek, Eli, E-mail: tea.temim@nasa.gov [Observational Cosmology Lab, Code 665, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2013-09-01

    Recent far-infrared (IR) observations of supernova remnants (SNRs) have revealed significantly large amounts of newly condensed dust in their ejecta, comparable to the total mass of available refractory elements. The dust masses derived from these observations assume that all the grains of a given species radiate at the same temperature, regardless of the dust heating mechanism or grain radius. In this paper, we derive the dust mass in the ejecta of the Crab Nebula, using a physical model for the heating and radiation from the dust. We adopt a power-law distribution of grain sizes and two different dust compositions (silicates and amorphous carbon), and calculate the heating rate of each dust grain by the radiation from the pulsar wind nebula. We find that the grains attain a continuous range of temperatures, depending on their size and composition. The total mass derived from the best-fit models to the observed IR spectrum is 0.019-0.13 M{sub Sun }, depending on the assumed grain composition. We find that the power-law size distribution of dust grains is characterized by a power-law index of 3.5-4.0 and a maximum grain size larger than 0.1 {mu}m. The grain sizes and composition are consistent with what is expected for dust grains formed in a Type IIP supernova (SN). Our derived dust mass is at least a factor of two less than the mass reported in previous studies of the Crab Nebula that assumed more simplified two-temperature models. These models also require a larger mass of refractory elements to be locked up in dust than was likely available in the ejecta. The results of this study show that a physical model resulting in a realistic distribution of dust temperatures can constrain the dust properties and affect the derived dust masses. Our study may also have important implications for deriving grain properties and mass estimates in other SNRs and for the ultimate question of whether SNe are major sources of dust in the Galactic interstellar medium and in external galaxies.

  11. Superconnections and Matter

    E-Print Network [OSTI]

    Roepstorff, G

    1998-01-01

    In a previous paper, the superconnection formalism was used to naturally fit the Higgs field into a U(n) gauge theory where we aimed at the reconstruction of the standard model. The approach provides an alternative to non-commutative geometry. This work is now continued by including matter field (leptons). The essentially new ingredient is the right-handed neutrino field and a new kind of interaction that goes with it. All interactions follow from one Dirac operator associated to a superconnection.

  12. Superconnections and Matter

    E-Print Network [OSTI]

    G. Roepstorff

    2000-08-17

    In a previous paper (hep-th/9801040), the superconnection formalism was used to fit the Higgs field into a U(n) gauge theory with particular emphasis on the n=2 case, aiming at the reconstruction of certain parts of the Standard Model. The approach provides an alternative to the one bases on non-commutative geometry. This work is continued by including matter fields (leptons only). We extend the Standard Model by including the right-handed neutrino field. The possibility of a finite neutrino mass is thus accounted for.

  13. Discrete dark matter

    SciTech Connect (OSTI)

    Hirsch, M.; Morisi, S.; Peinado, E.; Valle, J. W. F. [AHEP Group, Institut de Fisica Corpuscular--C.S.I.C./Universitat de Valencia, Edificio Institutos de Paterna, Apartado 22085, E-46071 Valencia (Spain)

    2010-12-01

    We propose a new motivation for the stability of dark matter (DM). We suggest that the same non-Abelian discrete flavor symmetry which accounts for the observed pattern of neutrino oscillations, spontaneously breaks to a Z{sub 2} subgroup which renders DM stable. The simplest scheme leads to a scalar doublet DM potentially detectable in nuclear recoil experiments, inverse neutrino mass hierarchy, hence a neutrinoless double beta decay rate accessible to upcoming searches, while {theta}{sub 13}=0 gives no CP violation in neutrino oscillations.

  14. Thermodynamics of electroweak matter

    E-Print Network [OSTI]

    A. Gynther

    2006-09-21

    This paper is a slightly modified version of the introductory part of a PhD thesis, also containing the articles hep-ph/0303019, hep-ph/0510375 and hep-ph/0512177. We provide a short history of the research of electroweak thermodynamics and a brief introduction to the theory as well as to the necessary theoretical tools needed to work at finite temperatures. We then review computations regarding the pressure of electroweak matter at high temperatures (the full expression of the perturbative expansion of the pressure is given in the appendix) and the electroweak phase diagram at finite chemical potentials. Finally, we compare electroweak and QCD thermodynamics.

  15. Dark matter axions

    SciTech Connect (OSTI)

    Sikivie, P. (California Univ., Santa Barbara, CA (United States). Inst. for Theoretical Physics Florida Univ., Gainesville, FL (United States). Dept. of Physics)

    1992-01-01

    The physics of axions is briefly reviewed theoretically, and various constraints on the axion mass are recounted. Then the two main contributions to the present cosmological axion energy density, that due to the realignment of the vacuum during the QCD phase transition and that from axions radiated by cosmic axion strings, are discussed. Next, two detection schemes for axions that are sensitive to different mass ranges, an electromagnetic cavity permeated by a strong magnetic field and a system of superconducting wires embedded in a material transparent to microwave radiation, are described. Finally, the phase space structure of cold dark matter galactic halos is considered. (RWR)

  16. Dark matter axions

    SciTech Connect (OSTI)

    Sikivie, P. [California Univ., Santa Barbara, CA (United States). Inst. for Theoretical Physics]|[Florida Univ., Gainesville, FL (United States). Dept. of Physics

    1992-09-01

    The physics of axions is briefly reviewed theoretically, and various constraints on the axion mass are recounted. Then the two main contributions to the present cosmological axion energy density, that due to the realignment of the vacuum during the QCD phase transition and that from axions radiated by cosmic axion strings, are discussed. Next, two detection schemes for axions that are sensitive to different mass ranges, an electromagnetic cavity permeated by a strong magnetic field and a system of superconducting wires embedded in a material transparent to microwave radiation, are described. Finally, the phase space structure of cold dark matter galactic halos is considered. (RWR)

  17. Materials/Condensed Matter

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesse BergkampCentermillion toMSDSMaterials andMaterials/Condensed Matter Print

  18. Double-Disk Dark Matter

    E-Print Network [OSTI]

    Fan, JiJi; Randall, Lisa; Reece, Matthew

    2013-01-01

    Based on observational tests and constraints on halo structure, dark matter is generally taken to be cold and essentially collisionless. On the other hand, given the large number of particles and forces in the visible world, a more complex dark sector could be a reasonable or even likely possibility. This hypothesis leads to testable consequences, perhaps portending the discovery of a rich hidden world neighboring our own. We consider a scenario that readily satisfies current bounds that we call Partially Interacting Dark Matter (PIDM). This scenario contains self-interacting dark matter, but it is not the dominant component. Even if PIDM contains only a fraction of the net dark matter density, comparable to the baryonic fraction, the subdominant component's interactions can lead to interesting and potentially observable consequences. Our primary focus will be the special case of Double-Disk Dark Matter (DDDM), in which self-interactions allow the dark matter to lose enough energy to lead to dynamics similar ...

  19. Color-based tracking of plasma dust particles

    SciTech Connect (OSTI)

    Villamayor, Michelle Marie S. Soriano, Maricor N.; Ramos, Henry J.; Kato, Shuichi; Wada, Motoi

    2014-02-15

    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.

  20. Experimental evidence of water formation on interstellar dust grains

    E-Print Network [OSTI]

    Dulieu, F; Fillion, J-H; Matar, E; Momeni, A; Pirronello, V; Lemaire, J L

    2009-01-01

    The synthesis of water is one necessary step in the origin and development of life. It is believed that pristine water is formed and grows on the surface of icy dust grains in dark interstellar clouds. Until now, there has been no experimental evidence whether this scenario is feasible or not. We present here the first experimental evidence of water synthesis under interstellar conditions. After D and O deposition on a water ice substrate (HO) held at 10 K, we observe production of HDO and DO. The water substrate itself has an active role in water formation, which appears to be more complicated than previously thought. Amorphous water ice layers are the matrices where complex organic prebiotic species may be synthesized. This experiment opens up the field of a little explored complex chemistry that could occur on interstellar dust grains, believed to be the site of key processes leading to the molecular diversity and complexity observed in our universe.

  1. Spherically symmetric cosmological spacetimes with dust and radiation — numerical implementation

    SciTech Connect (OSTI)

    Lim, Woei Chet [Department of Mathematics, University of Waikato, Private Bag 3105, Hamilton 3240 (New Zealand); Regis, Marco [Dipartimento di Fisica, Università di Torino and INFN, Torino (Italy); Clarkson, Chris, E-mail: wclim@waikato.ac.nz, E-mail: regis@to.infn.it, E-mail: chris.clarkson@gmail.com [Astrophysics, Cosmology and Gravity Centre, and Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch 7701, Cape Town (South Africa)

    2013-10-01

    We present new numerical cosmological solutions of the Einstein Field Equations. The spacetime is spherically symmetric with a source of dust and radiation approximated as a perfect fluid. The dust and radiation are necessarily non-comoving due to the inhomogeneity of the spacetime. Such a model can be used to investigate non-linear general relativistic effects present during decoupling or big-bang nucleosynthesis, as well as for investigating void models of dark energy with isocurvature degrees of freedom. We describe the full evolution of the spacetime as well as the redshift and luminosity distance for a central observer. After demonstrating accuracy of the code, we consider a few example models, and demonstrate the sensitivity of the late time model to the degree of inhomogeneity of the initial radiation contrast.

  2. Naked singularities in higher dimensional inhomogeneous dust collapse

    E-Print Network [OSTI]

    S G Ghosh; A Beesham

    2001-06-27

    We investigate the occurrence and nature of a naked singularity in the gravitational collapse of an inhomogeneous dust cloud described by a non self-similar higher dimensional Tolman spacetime. The necessary condition for the formation of a naked singularity or a black hole is obtained. The naked singularities are found to be gravitationally strong in the sense of Tipler and provide another example that violates the cosmic censorship conjecture.

  3. Canadian House Dust Study: Lead Bioaccessibility and Speciation

    SciTech Connect (OSTI)

    P Rasmussen; S Beauchemin; M Chenier; C Levesque; L MacLean; L Marrow; H Jones-Otazo; S Petrovic; L McDonald; H Gardner

    2011-12-31

    Vacuum samples were collected from 1025 randomly selected urban Canadian homes to investigate bioaccessible Pb (Pb{sub S}) concentrations in settled house dust. Results indicate a polymodal frequency distribution, consisting of three lognormally distributed subpopulations defined as 'urban background' (geomean 58 {micro}g g{sup -1}), 'elevated' (geomean 447 {micro}g g{sup -1}), and 'anomalous' (geomean 1730 {micro}g g{sup -1}). Dust Pb{sub S} concentrations in 924 homes (90%) fall into the 'urban background' category. The elevated and anomalous subpopulations predominantly consist of older homes located in central core areas of cities. The influence of house age is evidenced by a moderate correlation between house age and dust Pb{sub S} content (R{sup 2} = 0.34; n = 1025; p < 0.01), but it is notable that more than 10% of homes in the elevated/anomalous category were built after 1980. Conversely, the benefit of home remediation is evidenced by the large number of homes (33%) in the background category that were built before 1960. The dominant dust Pb species determined using X-ray Absorption Spectroscopy were as follows: Pb carbonate, Pb hydroxyl carbonate, Pb sulfate, Pb chromate, Pb oxide, Pb citrate, Pb metal, Pb adsorbed to Fe- and Al-oxyhydroxides, and Pb adsorbed to humate. Pb bioaccessibility estimated from solid phase speciation predicts Pb bioaccessibility measured using a simulated gastric extraction (R{sup 2} = 0.85; n = 12; p < 0.0001). The trend toward increased Pb bioaccessibility in the elevated and anomalous subpopulations (75% {+-} 18% and 81% {+-} 8%, respectively) compared to background (63% {+-} 18%) is explained by the higher proportion of bioaccessible compounds used as pigments in older paints (Pb carbonate and Pb hydroxyl carbonate). This population-based study provides a nationally representative urban baseline for applications in human health risk assessment and risk management.

  4. Chemical Dust Treatment of Cottonseed for Planting Purposes. 

    E-Print Network [OSTI]

    Smith, H. P. (Harris Pearson)

    1936-01-01

    -. lHEMICAL DUST TREATMENT OF COTTONSEED FOR PLANTING PURPOSES H. P. Smith, Chief, Division of Agricultural Engineering D. L. Jones, Superintendent, Substation No. 8, Lubl~ock D. T. Killough, Agronomist, Division of Agronomy H. C. Mc... Reports 3 6 to 41, inclusive. 10. Killough, D. T., "Cottonseed Treatment Proves Profitable." Progres- sive Farmer, Vol. 4 8, No. 3, March 19 3 3. 11. Lehman, S. G., "Studies on Treatment of Cottonseed." North Caro- lina Agricultural Experiment Station...

  5. Dark matter burners

    E-Print Network [OSTI]

    Moskalenko, I V

    2006-01-01

    We show that a star orbiting close enough to an adiabatically grown supermassive black hole can capture a large number of weakly interacting massive particles (WIMPs) during its lifetime. WIMP annihilation energy release in low- to medium-mass stars is comparable with or even exceeds the luminosity of such stars due to thermonuclear burning. The excessive energy release in the stellar core may result in an evolution scenario different from what is expected for a regular star. The model thus predicts the existence of unusual stars within the central parsec of galactic nuclei. If found, such stars would provide evidence for the existence of particle dark matter. The excess luminosity of such stars attributed to WIMP "burning" can be used to infer the local WIMP matter density. A white dwarf with a highly eccentric orbit around the central black hole may exhibit variations in brightness correlated with the orbital phase. On the other hand, white dwarfs shown to lack such orbital brightness variations can be used...

  6. The dust acoustic waves in three dimensional scalable complex plasma

    E-Print Network [OSTI]

    Zhukhovitskii, D I

    2015-01-01

    Dust acoustic waves in the bulk of a dust cloud in complex plasma of low pressure gas discharge under microgravity conditions are considered. The dust component of complex plasma is assumed a scalable system that conforms to the ionization equation of state (IEOS) developed in our previous study. We find singular points of this IEOS that determine the behavior of the sound velocity in different regions of the cloud. The fluid approach is utilized to deduce the wave equation that includes the neutral drag term. It is shown that the sound velocity is fully defined by the particle compressibility, which is calculated on the basis of the scalable IEOS. The sound velocities and damping rates calculated for different 3D complex plasmas both in ac and dc discharges demonstrate a good correlation with experimental data that are within the limits of validity of the theory. The theory provides interpretation for the observed independence of the sound velocity on the coordinate and for a weak dependence on the particle ...

  7. Modelling the Deep Counts: Luminosity Evolution, Dust and Faint Galaxies

    E-Print Network [OSTI]

    Ana Campos; Tom Shanks

    1995-11-23

    In this paper we analyse the deep number counts problem, taking account of new observational and theoretical developments. First we show that the new Bruzual and Charlot (1993) models allow a new class of spiral dominated luminosity evolution (LE) model where significant amounts of the luminosity evolution needed to fit faint count data are due to spiral rather than early-type galaxies. Second we show that the inclusion of dust may be a vital ingredient for obtaining fits with any LE model. Third we compare the quality of fit of both the spiral and early-type LE models, including dust, for a wide variety of observational data. We find that parameters can be found for both LE models which allow a good fit to all data with the exception of the faintest B>25 counts in the case of q0=0.5 cosmologies, where some luminosity dependent evolution may be needed (see also Metcalfe et al 1995). Otherwise both these classes of LE model, with the inclusion of dust, provide an excellent foundation for understanding the B<25 galaxy counts and galaxy counts and redshift distributions in a variety of other wavebands.

  8. Spherical Domain Wall Collapse in a Dust Universe

    E-Print Network [OSTI]

    Norihiro Tanahashi; Chul-Moon Yoo

    2015-05-13

    To clarify observational consequence of bubble nucleations in inflationary era, we analyse dynamics of a spherical domain wall in an expanding universe. We consider a spherical shell of the domain wall with tension $\\sigma$ collapsing in a spherically-symmetric dust universe, which is initially separated into the open Friedmann-Lema\\^itre-Robertson-Walker universe inside the shell and the Einstein-de Sitter universe outside. The domain wall shell collapses due to the tension, and sweeps the dust fluid. The universe after the collapse becomes inhomogeneous and is described by the Lema\\^itre-Tolman-Bondi model. We construct solutions describing this inhomogeneous universe by solving dynamical equations obtained from Israel's junction conditions applied to this system. We find that a black hole forms after the domain wall collapse for any initial condition, and that the black hole mass at the moment of its formation is universally given by $M_{\\rm BH}\\simeq 17 \\sigma/H_{\\rm hc}$, where $H_{\\rm hc}$ is the Hubble parameter at the time when the shell radius becomes equal to the Hubble radius. We also find that the dust fluid is distributed as $\\rho\\propto R^{3/2}$ near the central region after the collapse, where $R$ is the area radius. These features would provide observable signatures of a spherical domain wall generated in the early universe.

  9. Condensed Matter and Magnet Science

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

    helimagnets and the development of a cryogen-free apparatus for spherical neutron polarimetry." Read more... Cutting-edge condensed matter physics research, high magnetic field...

  10. Solving the Dark Matter Problem

    ScienceCinema (OSTI)

    Baltz, Ted

    2009-09-01

    Cosmological observations have firmly established that the majority of matter in the universe is of an unknown type, called 'dark matter'. A compelling hypothesis is that the dark matter consists of weakly interacting massive particles (WIMPs) in the mass range around 100 GeV. If the WIMP hypothesis is correct, such particles could be created and studied at accelerators. Furthermore they could be directly detected as the primary component of our galaxy. Solving the dark matter problem requires that the connection be made between the two. We describe some theoretical and experimental avenues that might lead to this connection.

  11. Nuclear Matter and Nuclear Dynamics

    E-Print Network [OSTI]

    M Colonna

    2009-02-26

    Highlights on the recent research activity, carried out by the Italian Community involved in the "Nuclear Matter and Nuclear Dynamics" field, will be presented.

  12. The Use of Oil Refinery Wastes as a Dust Suppression Surfactant for Use in Mining

    SciTech Connect (OSTI)

    Dixon-Hardy, D.W.; Beyhan, S.; Ediz, I.G.; Erarslan, K.

    2008-10-15

    In this research, the suitability of a selection of petroleum refinery wastes as a dust suppressant were examined. Dust is a significant problem in surface and underground mining mainly because of its adverse effects on human health and machinery. Hence, dust control and suppression is a vital part of mine planning for mining engineers. Water is the oldest and the cheapest suppressant in dealing with the mine dusts. However, surfactant use has recently been used for a wider range of applications in the mining industry. In order to carry out laboratory experiments, a dust chamber was designed and manufactured. The chamber has an inlet for coal dust entrance and a nozzle for spraying water and the oil refinery wastes. Water and the surfactants were mixed at various ratios and then sprayed onto the coal dusts within the cell. Dust concentration was measured systematically to determine the effects of surfactant containing solution on the coal dust and the data obtained by the measurements were analyzed. The results showed that the oil refinery wastes could be used as a dust suppressant, which may create an economical utilization for the wastes concerned.

  13. Regional Modeling of Dust Mass Balance and Radiative Forcing over East Asia using WRF-Chem

    SciTech Connect (OSTI)

    Chen, Siyu; Zhao, Chun; Qian, Yun; Leung, Lai-Yung R.; Huang, J.; Huang, Zhongwei; Bi, Jianrong; Zhang, Wu; Shi, Jinsen; Yang, Lei; Li, Deshuai; Li, Jinxin

    2014-12-01

    The Weather Research and Forecasting model with Chemistry (WRF-Chem) is used to investigate the seasonal and annual variations of mineral dust over East Asia during 2007-2011, with a focus on the dust mass balance and radiative forcing. A variety of measurements from in-stu and satellite observations have been used to evaluate simulation results. Generally, WRF-Chem reproduces not only the column variability but also the vertical profile and size distribution of mineral dust over and near the dust source regions of East Asia. We investigate the dust lifecycle and the factors that control the seasonal and spatial variations of dust mass balance and radiative forcing over the seven sub-regions of East Asia, i.e. source regions, the Tibetan Plateau, Northern China, Southern China, the ocean outflow region, and Korea-Japan regions. Results show that, over the source regions, transport and dry deposition are the two dominant sinks. Transport contributes to ~30% of the dust sink over the source regions. Dust results in a surface cooling of up to -14 and -10 W m-2, atmospheric warming of up to 20 and 15 W m-2, and TOA cooling of -5 and -8 W m-2 over the two major dust source regions of East Asia, respectively. Over the Tibetan Plateau, transport is the dominant source with a peak in summer. Over identified outflow regions, maximum dust mass loading in spring is contributed by the transport. Dry and wet depositions are the comparably dominant sinks, but wet deposition is larger than dry deposition over the Korea-Japan region, particularly in spring (70% versus 30%). The WRF-Chem simulations can generally capture the measured features of dust aerosols and its radaitve properties and dust mass balance over East Asia, which provides confidence for use in further investigation of dust impact on climate over East Asia.

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

    SciTech Connect (OSTI)

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

    2013-11-05

    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.

  15. Tropical biomass burning smoke plume size, shape, reflectance, and age based on 2001â??2009 MISR imagery of Borneo

    E-Print Network [OSTI]

    Zender, C. S.; Krolewski, A. G.; Tosca, M. G.; Randerson, J. T.

    2012-01-01

    C. S. Zender et al. : Tropical biomass burning smoke plumeslaboratory measurements of biomass-burning emis- sions: 1.aerosol optical depth biomass burning events: a comparison

  16. Tropical biomass burning smoke plume size, shape, reflectance, and age based on 2001-2009 MISR imagery of Borneo

    E-Print Network [OSTI]

    Zender, CS; Krolewski, AG; Tosca, MG; Randerson, JT

    2012-01-01

    C. S. Zender et al. : Tropical biomass burning smoke plumeslaboratory measurements of biomass-burning emis- sions: 1.aerosol optical depth biomass burning events: a comparison

  17. Dark matter burners

    E-Print Network [OSTI]

    Moskalenko, I V; Moskalenko, Igor V.; Wai, Lawrence L.

    2007-01-01

    We show that a star orbiting close enough to an adiabatically grown supermassive black hole (SMBH) can capture weakly interacting massive particles (WIMPs) at an extremely high rate. The stellar luminosity due to annihilation of captured WIMPs in the stellar core may be comparable to or even exceed the luminosity of the star due to thermonuclear burning. The model thus predicts the existence of unusual stars, essentially WIMP burners, in the vicinity of a SMBH. We find that the most efficient WIMP burners are stars with degenerate electron cores, e.g. white dwarfs (WDs); such WDs may have a very high surface temperature. If found, such stars would provide evidence for the existence of particle dark matter and can possibly be used to establish its density profile. On the other hand, the lack of such unusual stars may provide constraints on the WIMP density near the SMBH, as well as the WIMP-nucleus scattering and pair annihilation cross-sections.

  18. Dark matter burners

    E-Print Network [OSTI]

    Igor V. Moskalenko; Lawrence L. Wai

    2007-02-24

    We show that a star orbiting close enough to an adiabatically grown supermassive black hole (SMBH) can capture weakly interacting massive particles (WIMPs) at an extremely high rate. The stellar luminosity due to annihilation of captured WIMPs in the stellar core may be comparable to or even exceed the luminosity of the star due to thermonuclear burning. The model thus predicts the existence of unusual stars, essentially WIMP burners, in the vicinity of a SMBH. We find that the most efficient WIMP burners are stars with degenerate electron cores, e.g. white dwarfs (WDs); such WDs may have a very high surface temperature. If found, such stars would provide evidence for the existence of particle dark matter and can possibly be used to establish its density profile. On the other hand, the lack of such unusual stars may provide constraints on the WIMP density near the SMBH, as well as the WIMP-nucleus scattering and pair annihilation cross-sections.

  19. Accretion of dust grains as a possible origin of metal-poor stars with low alpha/Fe ratios

    E-Print Network [OSTI]

    Shigeyama, T; Shigeyama, Toshikazu; Tsujimoto, Takuji

    2003-01-01

    The origin of low alpha/Fe ratios in some metal-poor stars, so called low-alpha stars, is discussed. It is found that most of low-alpha stars in the Galaxy are on the main-sequence. This strongly suggests that these stars suffered from external pollution. It is also found that the abundance ratios Zn/Fe of low-alpha stars both in the Galaxy and in dwarf spheroidal galaxies are lower than the average value of Galactic halo stars whereas damped Ly alpha absorbers have higher ratios. This implies that some low-alpha stars accreted matter depleted from gas onto dust grains. To explain the features in these low-alpha stars, we have proposed that metal-poor stars harboring planetary systems are the origin of these low-alpha stars. Stars engulfing a small fraction of planetesimals enhance the surface content of Fe to exhibit low alpha/Fe ratios on their surfaces while they are on the main-sequence, because dwarfs have shallow surface convection zones where the engulfed matter is mixed. After the stars leave the main...

  20. Accretion of dust grains as a possible origin of metal-poor stars with low alpha/Fe ratios

    E-Print Network [OSTI]

    Toshikazu Shigeyama; Takuji Tsujimoto

    2003-10-10

    The origin of low alpha/Fe ratios in some metal-poor stars, so called low-alpha stars, is discussed. It is found that most of low-alpha stars in the Galaxy are on the main-sequence. This strongly suggests that these stars suffered from external pollution. It is also found that the abundance ratios Zn/Fe of low-alpha stars both in the Galaxy and in dwarf spheroidal galaxies are lower than the average value of Galactic halo stars whereas damped Ly alpha absorbers have higher ratios. This implies that some low-alpha stars accreted matter depleted from gas onto dust grains. To explain the features in these low-alpha stars, we have proposed that metal-poor stars harboring planetary systems are the origin of these low-alpha stars. Stars engulfing a small fraction of planetesimals enhance the surface content of Fe to exhibit low alpha/Fe ratios on their surfaces while they are on the main-sequence, because dwarfs have shallow surface convection zones where the engulfed matter is mixed. After the stars leave the main-sequence, the surface convection zones become deeper to reduce the enhancement of Fe. Eventually, when the stars ascend to the tip of the red giant branch, they engulf giant planets to become low-alpha stars again as observed in dwarf spheroidal galaxies. We predict that low-alpha stars with low Mn/Fe ratios harbor planetary systems.

  1. A preliminary assessment of beryllium dust oxidation during a wet bypass accident in a fusion reactor

    SciTech Connect (OSTI)

    Brad J. Merrill; Richard L. Moore; J. Phillip Sharp

    2008-09-01

    A beryllium dust oxidation model has been developed at the Idaho National Laboratory (INL) by the Fusion Safety Program (FSP) for the MELCOR safety computer code. The purpose of this model is to investigate hydrogen production from beryllium dust layers on hot surfaces inside a fusion reactor vacuum vessel (VV) during in-vessel loss-of-cooling accidents (LOCAs). This beryllium dust oxidation model accounts for the diffusion of steam into a beryllium dust layer, the oxidation of the dust particles inside this layer based on the beryllium-steam oxidation equations developed at the INL, and the effective thermal conductivity of this beryllium dust layer. This paper details this oxidation model and presents the results of the application of this model to a wet bypass accident scenario in the ITER device.

  2. Energy Matters in Washington State

    E-Print Network [OSTI]

    Collins, Gary S.

    Energy Matters in Washington State Energy Matters in Washington State www.energy.wsu.edu/library/ November 2009 #12;905 Plum Street SE, Building 3 P.O. Box 43169 Olympia, Washington 98504-3169 Energy University Extension Energy Program. 905 Plum Street SE, Building 3, P.O. Box 43169, Olympia, Washington

  3. Astronomical Evidence for Dark Matter

    E-Print Network [OSTI]

    Golwala, Sunil

    dark matter (assumed non-baryonic) #12;A word about constitutes an energy density from the Friedmann Equation: (Assuming no curvature) #12;Definitions C Critical Density X X/C = 1 => flat universe, what Rotation curve: Virial Theorem: #12;Spiral Galaxies Luminous Matter ~ follows: Asymptotes to constant value

  4. dark matter dark energy inflation

    E-Print Network [OSTI]

    Hu, Wayne

    theory dark matter dark energy inflation The National Science Foundation The Kavli Foundation NSF Site Review November 28-29, 2005 #12;dark matter dark energy inflation NSF Site Visit ­ November 28 - 29, 2005The National Science Foundation The Kavli Foundation The Theoretical Web UHE cosmic rays B

  5. Dark matter on the lattice

    E-Print Network [OSTI]

    Randy Lewis

    2014-11-26

    Several collaborations have recently performed lattice calculations aimed specifically at dark matter, including work with SU(2), SU(3), SU(4) and SO(4) gauge theories to represent the dark sector. Highlights of these studies are presented here, after a reminder of how lattice calculations in QCD itself are helping with the hunt for dark matter.

  6. Charmonium mass in nuclear matter 

    E-Print Network [OSTI]

    Lee, S. H.; Ko, Che Ming.

    2003-01-01

    The mass shift of charmonium states in nuclear matter is studied in the perturbative QCD approach. The leading-order effect due to the change of gluon condensate in nuclear matter is evaluated using the leading-order QCD formula, while the higher...

  7. Quantum vacuum and dark matter

    E-Print Network [OSTI]

    Dragan Slavkov Hajdukovic

    2011-11-21

    Recently, the gravitational polarization of the quantum vacuum was proposed as alternative to the dark matter paradigm. In the present paper we consider four benchmark measurements: the universality of the central surface density of galaxy dark matter haloes, the cored dark matter haloes in dwarf spheroidal galaxies, the non-existence of dark disks in spiral galaxies and distribution of dark matter after collision of clusters of galaxies (the Bullet cluster is a famous example). Only some of these phenomena (but not all of them) can (in principle) be explained by the dark matter and the theories of modified gravity. However, we argue that the framework of the gravitational polarization of the quantum vacuum allows the understanding of the totality of these phenomena.

  8. A Fluorescent Aerogel for Capture and Identification of Interplanetary and Interstellar Dust

    E-Print Network [OSTI]

    Gerardo Dominguez; Andrew J. Westphal; Mark L. F. Phillips; Steven M. Jones

    2003-03-27

    Contemporary interstellar dust has never been analyzed in the laboratory, despite its obvious astronomical importance and its potential as a probe of stellar nucleosynthesis and galactic chemical evolution. Here we report the discovery of a novel fluorescent aerogel which is capable of capturing hypervelocity dust grains and passively recording their kinetic energies. An array of these "calorimetric" aerogel collectors in low earth orbit would lead to the capture and identification of large numbers of interstellar dust grains.

  9. An investigation of dust storm generation in the Southern Great Plains 

    E-Print Network [OSTI]

    Pollard, Marshall Conrad

    1977-01-01

    of daily mean precipitation amounts and Antecedent Precipitation Index (API) profiles with number of stations reporting dust for February- May 1974 in four regions of the Southern Great Plains 43 Contoured frequency graph depicting the comparison... of monthly dust observations with time of day of occurrence, Contours are labeled in number of. observations and the data base includes 5056 dust reports from 34 Southern Great Plains stations during February-May 1966-1975 . . . . . . . . . . . 46 20...

  10. Experimental Investigation on Effect of Smoke Management System in a High-large Atrium

    SciTech Connect (OSTI)

    Chen, B.; Lu, S. X.; Li, C. H.; Hu, J. [State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, 230026, Anhui (China); Huang, Y. [State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, 230026, Anhui (China); Yunnan General Fire Brigade, Kunming, 650228, Yunnan (China); Zheng, Y. Q.; Chen, S. [Yunnan General Fire Brigade, Kunming, 650228, Yunnan (China)

    2010-05-21

    In an atrium measured 120 m by 180 m by 36.5 m high, fire tests were conducted under 'natural filling' and 'mechanical exhaust' conditions by hot smoke test method. The fire size was 8 MW released by an ethanol pool of 3.6 m in diameter. The distribution of vertical temperature profiles above the fire source and the gas layer temperatures were measured. From these measurements, it was shown that the fans successfully exhausted hot smoke to control descending of hot smoke layer and temperature rising rate. The hot smoke layer can be maintained at about 30 m which was almost 2 times of hot layer height in 'natural filling' condition. The temperature risings in both conditions were too low to cause thermal damage to the structure, only 18.6 K and 12 K. The centerline temperature above the fire source and the height of hot smoke layer were calculated using the plume models. The calculated results agreed well with the conclusions obtained from the experiment results.

  11. Naked singularities in cylindrical collapse of counter-rotating dust shells

    E-Print Network [OSTI]

    Brien C. Nolan

    2002-04-09

    Solutions describing the gravitational collapse of asymptotically flat cylindrical and prolate shells of (null) dust are shown to admit globally naked singularities.

  12. THE CHEMICALLY CONTROLLED SYNTHESIS OF DUST IN TYPE II-P SUPERNOVAE

    SciTech Connect (OSTI)

    Sarangi, Arkaprabha; Cherchneff, Isabelle, E-mail: arkaprabha.sarangi@unibas.ch, E-mail: isabelle.cherchneff@unibas.ch [Departement Physik, Universität Basel, CH-4056 Basel (Switzerland)

    2013-10-20

    We study the formation of molecules and dust clusters in the ejecta of solar metallicity, Type II-P supernovae (SNe) using a chemical kinetic approach. We follow the evolution of molecules and small dust cluster masses from day 100 to day 1500 after explosion. We consider stellar progenitors with initial masses of 12, 15, 19, and 25 M{sub ?} that explode as SNe with stratified ejecta. The molecular precursors to dust grains comprise molecular chains, rings and small clusters of silica, silicates, metal oxides, sulfides and carbides, pure metals, and carbon, where the nucleation of silicate clusters is described by a two-step process of metal and oxygen addition. We study the impact of the {sup 56}Ni mass on the type and amount of synthesized dust. We predict that large masses of molecules including CO, SiO, SiS, O{sub 2}, and SO form in the ejecta. We show that the discrepancy between the small dust masses detected at infrared wavelengths some 500 days post-explosion and the larger amounts of dust recently detected with Herschel in SN remnants can be explained by the non-equilibrium chemistry linked to the formation of molecules and dust clusters in the ejected material. Dust gradually builds up from small (?10{sup –5} M{sub ?}) to large masses (?5 × 10{sup –2} M{sub ?}) over a 5 yr period after explosion. Subsequent dust formation and/or growth is hampered by the shortage of chemical agents participating in the dust nucleation and the long timescale for accretion. The results highlight the dependence of the dust chemical composition and mass on the amount of {sup 56}Ni synthesized during the explosion. This dependence may partly explain the diversity of epochs at which dust forms in SNe. More generally, our results indicate that Type II-P SNe are efficient but moderate dust producers with an upper limit on the mass of synthesized dust ranging from ?0.03 to 0.09 M{sub ?}. Other dust sources must then operate at high redshift to explain the large quantities of dust present in young galaxies in the early universe.

  13. Understanding the 30-year Barbados desert dust record Natalie M. Mahowald,1

    E-Print Network [OSTI]

    Mahowald, Natalie

    (such as new sources due to desertification or land use) may be difficult to distinguish from: Aerosols (0305); KEYWORDS: mineral aerosols, desert dust, North Africa, desertification Citation: Mahowald

  14. The roles of non-extensivity and dust concentration as bifurcation parameters in dust-ion acoustic traveling waves in magnetized dusty plasma

    SciTech Connect (OSTI)

    Narayan Ghosh, Uday; Kumar Mandal, Pankaj, E-mail: pankajwbmsd@gmail.com; Chatterjee, Prasanta [Department of Mathematics, Siksha Bhavana Visva Bharati, Santiniketan, West Bengal 731235 (India)] [Department of Mathematics, Siksha Bhavana Visva Bharati, Santiniketan, West Bengal 731235 (India)

    2014-03-15

    Dust ion-acoustic traveling waves are studied in a magnetized dusty plasma in presence of static dust and non-extensive distributed electrons in the framework of Zakharov-Kuznesstov-Burgers (ZKB) equation. System of coupled nonlinear ordinary differential equations is derived from ZKB equation, and equilibrium points are obtained. Nonlinear wave phenomena are studied numerically using fourth order Runge-Kutta method. The change from unstable to stable solution and consequently to asymptotic stable of dust ion acoustic traveling waves is studied through dynamical system approach. It is found that some dramatical features emerge when the non-extensive parameter and the dust concentration parameters are varied. Behavior of the solution of the system changes from unstable to stable and stable to asymptotic stable depending on the value of the non-extensive parameter. It is also observed that when the dust concentration is increased the solution pattern is changed from oscillatory shocks to periodic solution. Thus, non-extensive and dust concentration parameters play crucial roles in determining the nature of the stability behavior of the system. Thus, the non-extensive parameter and the dust concentration parameters can be treated as bifurcation parameters.

  15. Nuclear-matter--quark-matter phase diagram with strangeness

    SciTech Connect (OSTI)

    Barz, H. W.; Friman, B. L.; Knoll, J.; Schulz, H.

    1989-07-01

    A phenomenological equation of state of strongly interacting matter, including strange degrees of freedom, is presented. It is shown that the hyperon and kaon interactions must be included, in order to obtain a reasonable description of the deconfinement transition at high baryon densities. The consequences of kaon condensation on the nuclear-matter--quark-matter phase diagram are explored. The relative particle abundances obtained in an isentropic expansion of a blob of quark-gluon plasma are presented for different initial conditions. Implications for ultrarelativistic heavy-ion collisions are briefly discussed.

  16. A classification of spherically symmetric self-similar dust models

    E-Print Network [OSTI]

    B. J. Carr

    2000-03-02

    We classify all spherically symmetric dust solutions of Einstein's equations which are self-similar in the sense that all dimensionless variables depend only upon $z\\equiv r/t$. We show that the equations can be reduced to a special case of the general perfect fluid models with equation of state $p=\\alpha \\mu$. The most general dust solution can be written down explicitly and is described by two parameters. The first one (E) corresponds to the asymptotic energy at large $|z|$, while the second one (D) specifies the value of z at the singularity which characterizes such models. The E=D=0 solution is just the flat Friedmann model. The 1-parameter family of solutions with z>0 and D=0 are inhomogeneous cosmological models which expand from a Big Bang singularity at t=0 and are asymptotically Friedmann at large z; models with E>0 are everywhere underdense relative to Friedmann and expand forever, while those with E0 ones. The 2-parameter solutions with D>0 again represent inhomogeneous cosmological models but the Big Bang singularity is at $z=-1/D$, the Big Crunch singularity is at $z=+1/D$, and any particular solution necessarily spans both z0. While there is no static model in the dust case, all these solutions are asymptotically ``quasi-static'' at large $|z|$. As in the D=0 case, the ones with $E \\ge 0$ expand or contract monotonically but the latter may now contain a naked singularity. The ones with E<0 expand from or recollapse to a second singularity, the latter containing a black hole.

  17. Laser Driven Dynamic Loading of Condensed Matter

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

    Laser Driven Dynamic Loading of Condensed Matter Laser Driven Dynamic Loading of Condensed Matter Advanced diagnostics of experiments covering many orders of magnitude in strain...

  18. MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; SOLID STATE...

    Office of Scientific and Technical Information (OSTI)

    Open problems in condensed matter physics, 1987 Falicov, L.M. 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; SOLID STATE PHYSICS; RESEARCH PROGRAMS;...

  19. Ultrafast Spectroscopy of Warm Dense Matter

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

    of planet formation and structures as well as the evolution of an imploding inertial fusion capsule depends on our understanding of matter in the complex warm dense matter...

  20. Passive cigarette smoke, coal heating, and respiratory symptoms of nonsmoking women in China

    SciTech Connect (OSTI)

    Pope, C.A. III Brigham Young Univ., Provo, UT ); Xu, X. )

    1993-09-01

    In this study the authors evaluated data from a sample of 973 never-smoking women, ages 20-40, who worked in three similar textile mills in Anhui Province, China. They compared prevalence rates of respiratory symptoms across homes with and without coal heating and homes with different numbers of smokers. Multiple logistic regression models that controlled for age, job title, and mill of employment were also estimated. Respiratory symptoms were associated with combined exposure to passive cigarette smoke and coal heating. Effects of passive cigarette smoke and coal heating on respiratory symptoms appeared to be nearly additive, suggesting a dose-response relationship between respiratory symptoms and home indoor air pollution from these two sources. The prevalence of chest illness, cough, phlegm, and shortness of breath (but not wheeze) was significantly elevated for women living in homes with both smokers and coal heating.

  1. Particle creation in (2+1) circular dust collapse

    SciTech Connect (OSTI)

    Gutti, Sashideep; Singh, T. P.

    2007-09-15

    We investigate the quantum particle creation during the circularly symmetric collapse of a 2+1 dust cloud, for the cases when the cosmological constant is either zero or negative. We derive the Ford-Parker formula for the 2+1 case, which can be used to compute the radiated quantum flux in the geometric optics approximation. It is shown that no particles are created when the collapse ends in a naked singularity, unlike in the 3+1 case. When the collapse ends in a Banados-Teitelboim-Zanelli black hole, we recover the expected Hawking radiation.

  2. DUST TRANSPORT IN PROTOSTELLAR DISKS THROUGH TURBULENCE AND SETTLING

    SciTech Connect (OSTI)

    Turner, N. J.; Carballido, A. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Sano, T., E-mail: neal.turner@jpl.nasa.go [Institute of Laser Engineering, Osaka University, Suita, Osaka 565-0871 (Japan)

    2010-01-01

    We apply ionization balance and magnetohydrodynamical (MHD) calculations to investigate whether magnetic activity moderated by recombination on dust grains can account for the mass accretion rates and the mid-infrared spectra and variability of protostellar disks. The MHD calculations use the stratified shearing-box approach and include grain settling and the feedback from the changing dust abundance on the resistivity of the gas. The two-decade spread in accretion rates among solar-mass T Tauri stars is too large to result solely from variations in the grain size and stellar X-ray luminosity, but can plausibly be produced by varying these parameters together with the disk magnetic flux. The diverse shapes and strengths of the mid-infrared silicate bands can come from the coupling of grain settling to the distribution of the magnetorotational turbulence, through the following three effects. First, recombination on grains 1 mum or smaller yields a magnetically inactive dead zone extending more than two scale heights from the midplane, while turbulent motions in the magnetically active disk atmosphere overshoot the dead zone boundary by only about one scale height. Second, grains deep in the dead zone oscillate vertically in wave motions driven by the turbulent layer above, but on average settle at the rates found in laminar flow, so that the interior of the dead zone is a particle sink and the disk atmosphere will become dust-depleted unless resupplied from elsewhere. Third, with sufficient depletion, the dead zone is thinner and mixing dredges grains off the midplane. The last of these processes enables evolutionary signatures such as the degree of settling to sometimes decrease with age. The MHD results also show that the magnetic activity intermittently lifts clouds of small grains into the atmosphere. Consequently the photosphere height changes by up to one-third over timescales of a few orbits, while the extinction along lines of sight grazing the disk surface varies by factors of 2 over times down to a tenth of an orbit. We suggest that the changing shadows cast by the dust clouds on the outer disk are a cause of the daily to monthly mid-infrared variability found in many young stars.

  3. Dust: A major environmental hazard on the earth's moon

    SciTech Connect (OSTI)

    Heiken, G.; Vaniman, D.; Lehnert, B.

    1990-01-01

    On the Earth's Moon, obvious hazards to humans and machines are created by extreme temperature fluctuations, low gravity, and the virtual absence of any atmosphere. The most important other environmental factor is ionizing radiation. Less obvious environmental hazards that must be considered before establishing a manned presence on the lunar surface are the hazards from micrometeoroid bombardment, the nuisance of electro-statically-charged lunar dust, and an alien visual environment without familiar clues. Before man can establish lunar bases and lunar mining operations, and continue the exploration of that planet, we must develop a means of mitigating these hazards. 4 refs.

  4. Geometrodynamics in a spherically symmetric, static crossflow of null dust

    E-Print Network [OSTI]

    Zsolt Horváth; Zoltán Kovács; László Á. Gergely

    2006-10-12

    The spherically symmetric, static spacetime generated by a crossflow of non-interacting radiation streams, treated in the geometrical optics limit (null dust) is equivalent to an anisotropic fluid forming a radiation atmosphere of a star. This reference fluid provides a preferred / internal time, which is employed as a canonical coordinate. Among the advantages we encounter a new Hamiltonian constraint, which becomes linear in the momentum conjugate to the internal time (therefore yielding a functional Schr\\"{o}dinger equation after quantization), and a strongly commuting algebra of the new constraints.

  5. Geometrodynamics in a spherically symmetric, static crossflow of null dust

    E-Print Network [OSTI]

    Horváth, Z; Kovács, Z; Horv\\'{a}th, Zsolt; Kov\\'{a}cs, Zolt\\'{a}n

    2006-01-01

    The spherically symmetric, static spacetime generated by a crossflow of non-interacting radiation streams, treated in the geometrical optics limit (null dust) is equivalent to an anisotropic fluid forming a stellar atmosphere. This reference fluid provides a preferred / internal time, which is employed as a canonical coordinate. Among the advantages we encounter a new Hamiltonian constraint, which becomes linear in the momentum conjugate to the internal time (therefore yielding a functional Schr\\"{o}dinger equation after quantization), and a strongly commuting algebra of the new constraints.

  6. Expansion of a spherical dust gas -- the cosmological conundrum

    E-Print Network [OSTI]

    Müller, Ingo

    2015-01-01

    The universe is viewed as a dust gas filling a sphere and floating in infinite empty space. Einstein's gravitational equations are applied to this case together with appropriate boundary values. The equations are solved for initial conditions chosen so as to describe the observed Hubble diagram. We find that the solution is not unique so that more astronomical observations are needed. However, those solutions which were found do not exhibit an accelerated expansion of the universe, nor -- obviously then -- do they need the notion of a dark energy driving such an expansion. We present this study as an alternative to the prevailing Robertson-Walker cosmology.

  7. Space Dust Analysis Could Provide Clues to Solar System Origins

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effect Photovoltaics -7541C. TemperatureThousand CubicArchived FOIASpace Dust

  8. Space Dust Analysis Could Provide Clues to Solar System Origins

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effect Photovoltaics -7541C. TemperatureThousand CubicArchived FOIASpace DustSpace

  9. Space Dust Analysis Could Provide Clues to Solar System Origins

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effect Photovoltaics -7541C. TemperatureThousand CubicArchived FOIASpaceSpace Dust

  10. Space Dust Analysis Could Provide Clues to Solar System Origins

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque|SensitiveApril 2, 2014 Smith Named as NewAprilSpaceSpace Dust

  11. Passive smoking, air pollution, and acute respiratory symptoms in a diary study of student nurses

    SciTech Connect (OSTI)

    Schwartz, J.; Zeger, S. )

    1990-01-01

    A cohort of approximately 100 student nurses in Los Angeles was recruited for a diary study of the acute effects of air pollution. Smoking histories and presence of asthma and other allergies were determined by questionnaire. Diaries were completed daily and collected weekly for as long as 3 yr. Air pollution was measured at a monitoring location within 2.5 miles of the school. Incidence and duration of a symptom were modeled separately. Pack-years of cigarettes were predictive of the number of episodes of coughing (p less than 0.0001) and of bringing up phlegm (p less than 0.0001). Current smoking, rather than cumulative smoking, was a better predictor of the duration of a phlegm episode (p less than 0.0001). Controlling for personal smoking, a smoking roommate increased the risk of an episode of phlegm (odds ratio (OR) = 1.41, p less than 0.001), but not of cough. Excluding asthmatics (who may be medicated), increased the odds ratio for passive smoking to 1.76 (p less than 0.0001). In logistic regression models controlling for temperature and serial correlation between days, an increase of 1 SD in carbon monoxide exposure (6.5 ppm) was associated with increased risk of headache (OR = 1.09, p less than 0.001), photochemical oxidants (7.4 pphm) were associated with increased risk of chest discomfort (OR = 1.17, p less than 0.001) and eye irritation (OR = 1.20 p less than 0.001), and nitrogen dioxide (9.1 pphm) was associated with increased risk of phlegm (OR = 1.08 p less than 0.01), sore throats (OR = 1.26, p less than 0.001), and eye irritation (OR = 1.16, p less than 0.001).

  12. Casting Light on Dark Matter

    E-Print Network [OSTI]

    John Ellis

    2011-06-15

    The prospects for detecting a candidate supersymmetric dark matter particle at the LHC are reviewed, and compared with the prospects for direct and indirect searches for astrophysical dark matter. The discussion is based on a frequentist analysis of the preferred regions of the Minimal supersymmetric extension of the Standard Model with universal soft supersymmetry breaking (the CMSSM). LHC searches may have good chances to observe supersymmetry in the near future - and so may direct searches for astrophysical dark matter particles, whereas indirect searches may require greater sensitivity, at least within the CMSSM.

  13. A mixed-methods study of young adults’ receptivity to using Facebook for smoking cessation: If you build it, will they come?

    E-Print Network [OSTI]

    Ramo, Danielle E; Liu, Howard; Prochaska, Judith J

    2013-01-01

    Development; 2008. AppData. Facebook Apps Leaderboard.use among young people. Facebook for smoking cessationBMC Public Health. 2009;9:32. Facebook for smoking cessation

  14. The Unification and Cogeneration of Dark Matter and Baryonic Matter

    E-Print Network [OSTI]

    S. M. Barr

    2011-09-18

    In grand unified theories with gauge groups larger than SU(5), the multiplets that contain the known quarks and leptons also contain fermions that are singlets under the Standard Model gauge group. Some of these could be the dark matter of the universe. Grand unified theories can also have accidental U(1) global symmetries (analogous to B-L in minimal SU(5)) that can stabilize dark matter. These ideas are illustrated in an SU(6) model.

  15. The Unification and Cogeneration of Dark Matter and Baryonic Matter

    E-Print Network [OSTI]

    Barr, S M

    2011-01-01

    In grand unified theories with gauge groups larger than SU(5), the multiplets that contain the known quarks and leptons also contain fermions that are singlets under the Standard Model gauge group. Some of these could be the dark matter of the universe. Grand unified theories can also have accidental U(1) global symmetries (analogous to B-L in minimal SU(5)) that can stabilize dark matter. These ideas are illustrated in an SU(6) model.

  16. LUNAR DUST GRAIN CHARGING BY ELECTRON IMPACT: COMPLEX ROLE OF SECONDARY ELECTRON EMISSIONS IN SPACE ENVIRONMENTS

    SciTech Connect (OSTI)

    Abbas, M. M.; Craven, P. D.; LeClair, A. C.; Spann, J. F.; Tankosic, D.

    2010-08-01

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, or by electron/ion collisions by sticking or secondary electron emissions (SEEs). The high vacuum environment on the lunar surface leads to some unusual physical and dynamical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. Knowledge of the dust grain charges and equilibrium potentials is important for understanding a variety of physical and dynamical processes in the interstellar medium, and heliospheric, interplanetary/planetary, and lunar environments. It has been well recognized that the charging properties of individual micron-/submicron-size dust grains are expected to be substantially different from the corresponding values for bulk materials. In this paper, we present experimental results on the charging of individual 0.2-13 {mu}m size dust grains selected from Apollo 11 and 17 dust samples, and spherical silica particles by exposing them to mono-energetic electron beams in the 10-200 eV energy range. The dust charging process by electron impact involving the SEEs discussed is found to be a complex charging phenomenon with strong particle size dependence. The measurements indicate substantial differences between the polarity and magnitude of the dust charging rates of individual small-size dust grains, and the measurements and model properties of corresponding bulk materials. A more comprehensive plan of measurements of the charging properties of individual dust grains for developing a database for realistic models of dust charging in astrophysical and lunar environments is in progress.

  17. Detection of smoke and ash from forest fires and volcanic eruptions using the GOME-2 Absorbing Aerosol Index

    E-Print Network [OSTI]

    Tilstra, Gijsbert

    Detection of smoke and ash from forest fires and volcanic eruptions using the GOME-2 Absorbing. Colours represent the smoke plume on the indicated days. 3. Detection of volcanic ash In April 2010, the GOME-2 AAI was able to follow the transport of volcanic ash from the Eyjafjalljokull volcano

  18. Genetic variants on 15q25.1, smoking and lung cancer: an assessment of mediation and interaction

    E-Print Network [OSTI]

    Lin, Xihong

    1 Genetic variants on 15q25.1, smoking and lung cancer: an assessment of mediation and interaction-wide association studies have identified variants on chromosome 15q25.1 that increase the risk of both lung cancer as to whether the association with lung cancer is direct or mediated by pathways related to smoking behavior

  19. Effectiveness of computer-tailored Smoking Cessation Advice in Primary Care (ESCAPE): a Randomised Trial

    E-Print Network [OSTI]

    Gilbert, Hazel; Nazareth, Irwin; Sutton, Stephen; Morris, Richard; Godfrey, Christine

    2008-04-29

    not fit all: the case for tailoring print materials. Annals of Behavioral Medi- cine 1999, 21:276-283. 11. Fiore MC, Novotny TE, Pierce JP, Giovino GA, Hatziandreu EJ: Meth- ods used to quit smoking in the United States. Do cessation programs help? JAMA... . Russell M, Wilson C, Taylor C, Baker CD: Effect of general prac- titioners' advice against smoking. BMJ 1979, 2:231-235.Page 8 of 8 (page number not for citation purposes) 22. Aveyard P, Griffin C, Lawrence T, Cheng KK: A controlled trial of an expert...

  20. Evolving Einstein's Field Equations with Matter: The ``Hydro without Hydro'' Test

    E-Print Network [OSTI]

    Thomas W. Baumgarte; Scott A. Hughes; Stuart L. Shapiro

    1999-02-09

    We include matter sources in Einstein's field equations and show that our recently proposed 3+1 evolution scheme can stably evolve strong-field solutions. We insert in our code known matter solutions, namely the Oppenheimer-Volkoff solution for a static star and the Oppenheimer-Snyder solution for homogeneous dust sphere collapse to a black hole, and evolve the gravitational field equations. We find that we can evolve stably static, strong-field stars for arbitrarily long times and can follow dust sphere collapse accurately well past black hole formation. These tests are useful diagnostics for fully self-consistent, stable hydrodynamical simulations in 3+1 general relativity. Moreover, they suggest a successive approximation scheme for determining gravitational waveforms from strong-field sources dominated by longitudinal fields, like binary neutron stars: approximate quasi-equilibrium models can serve as sources for the transverse field equations, which can be evolved without having to re-solve the hydrodynamical equations (``hydro without hydro'').

  1. Physical Protection of Classified Matter

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1988-02-03

    The order establishes policy and objectives for physical protection of classified matter. This directive does not cancel another directive. Chg 1, 7-30-93. Canceled by 5632.1C.

  2. Lorentz-violating dark matter 

    E-Print Network [OSTI]

    Mondragon, Antonio Richard

    2009-05-15

    was originally motivated by an unconventional fundamental theory, but which in this dissertation is defined as matter which has a nonzero minimum velocity. Furthermore, the present investigation evolved into the broader goal of exploring the properties of Lorentz...

  3. Energy Matters: Our Energy Independence

    Office of Energy Efficiency and Renewable Energy (EERE)

    In this installment of the livechat series "Energy Matters," Dr. Arun Majumdar takes questions from the public about the investments we're making today that will move us off of foreign oil and...

  4. Nonstationary stochastic charge fluctuations of a dust particle in plasmas

    SciTech Connect (OSTI)

    Shotorban, B.

    2011-06-15

    Stochastic charge fluctuations of a dust particle that are due to discreteness of electrons and ions in plasmas can be described by a one-step process master equation [T. Matsoukas and M. Russell, J. Appl. Phys. 77, 4285 (1995)] with no exact solution. In the present work, using the system size expansion method of Van Kampen along with the linear noise approximation, a Fokker-Planck equation with an exact Gaussian solution is developed by expanding the master equation. The Gaussian solution has time-dependent mean and variance governed by two ordinary differential equations modeling the nonstationary process of dust particle charging. The model is tested via the comparison of its results to the results obtained by solving the master equation numerically. The electron and ion currents are calculated through the orbital motion limited theory. At various times of the nonstationary process of charging, the model results are in a very good agreement with the master equation results. The deviation is more significant when the standard deviation of the charge is comparable to the mean charge in magnitude.

  5. Naked singularity explosion in higher-dimensional dust collapse

    E-Print Network [OSTI]

    Masahiro Shimano; Umpei Miyamoto

    2013-12-20

    In the context of the large extra dimensions or TeV-scale gravity, it has been argued that an effective naked singularity, called the visible border of spacetime, would be generated by high-energy particle collisions. Motivated by this interesting possibility, we investigate a particle creation by a naked singularity in general dimensions, adopting a spherically symmetric self-similar dust collapse as the simple model of a naked singularity formation. The power and energy of the particle emission behave in two distinct ways depending on a parameter in the model. In a generic case, the emission power is proportional to the quadratic inverse of the remaining time to the Cauchy horizon, which has been known for the four-dimensional case in the literature. On the other hand, in a degenerate case the emission power is proportional to the quartic inverse of the remaining time to the Cauchy horizon, and depends on the total mass of a dust fluid in spite that the central region of the collapse is scale-free due to the self-similarity. In the both cases, within a test-field approximation the energy radiated before any quantum gravitational effect dominates amounts to TeV. This suggests that a backreaction is not ignorable in the TeV-scale gravity context, in contrast to the similar phenomena in stellar collapse.

  6. Finite axisymmetric charged dust disks in conformastatic spacetimes

    SciTech Connect (OSTI)

    Gonzalez, Guillermo A.; Gutierrez-Pineres, Antonio C.; Ospina, Paolo A.

    2008-09-15

    An infinite family of axisymmetric charged dust disks of finite extension is presented. The disks are obtained by solving the vacuum Einstein-Maxwell equations for conformastatic spacetimes, which are characterized by only one metric function. In order to obtain the solutions, a functional relationship between the metric function and the electric potential is assumed. It is also assumed that the metric function is functionally dependent on another auxiliary function, which is taken as a solution of the Laplace equation. The solutions for the auxiliary function are then taken as given by the infinite family of generalized Kalnajs disks recently obtained by Gonzalez and Reina [G. A. Gonzalez and J. I. Reina, Mon. Not. R. Astron. Soc. 371, 1873 (2006).], expressed in terms of the oblate spheroidal coordinates and corresponding to a family of well-behaved Newtonian axisymmetric thin disks of finite radius. The obtained relativistic thin disks have a charge density that is equal, except maybe by a sign, to their mass density, in such a way that the electric and gravitational forces are in exact balance. The energy density of the disks is everywhere positive and well behaved, vanishing at the edge. Accordingly, as the disks are made of dust, their energy-momentum tensor agrees with all the energy conditions.

  7. Spectral solar irradiance before and during a Harmattan dust spell

    SciTech Connect (OSTI)

    Adeyefa, Z.D. [Federal Univ. of Technology, Akure (Nigeria)] [Federal Univ. of Technology, Akure (Nigeria); Holmgren, B. [Uppsala Univ. (Sweden)] [Uppsala Univ. (Sweden)

    1996-09-01

    Measurements of the ground-level spectral distributions of the direct, diffuse and global solar irradiance between 300 and 1100 nm were made at Akure (7.15{degree}N, 5.5{degree}E), Nigeria, in December 1991 before and during a Harmattan dust spell employing a spectroradiometer (LICOR LI-1800) with 6 nm resolution. The direct spectral solar irradiance which was initially reduced before the dust storm was further attenuated by about 50% after the spell. Estimated values of the Angstrom turbidity coefficient {beta} indicated an increase of about 146% of this parameter while the Angstrom wavelength-exponent {alpha} decreased by about 65% within the 2-day study period. The spectral diffuse-to-direct and diffuse-to-global ratios suggest that the main cause of the significant reduction in solar irradiance at the surface was the scattering by the aerosol which led to an increase in the diffuse component. The global irradiance though reduced, was less sensitive to changing Harmattan conditions. It is recommended that solar energy devices that use radiation from Sun and sky be used under fluctuating Harmattan conditions. There are some deviations from the Angstrom formula under very turbid Harmattan conditions which could be explained by the relative increase of the particle sizes. 31 refs., 12 figs., 3 tabs.

  8. Evidence for Environmental Changes in the Submillimeter Dust Opacity

    E-Print Network [OSTI]

    Martin, Peter G; Bontemps, Sylvain; Miville-Deschênes, Marc-Antoine; Ade, Peter A R; Bock, James J; Chapin, Edward L; Devlin, Mark J; Dicker, Simon R; Griffin, Matthew; Gundersen, Joshua O; Halpern, Mark; Hargrave, Peter C; Hughes, David H; Klein, Jeff; Marsden, Gaelen; Mauskopf, Philip; Netterfield, Calvin B; Olmi, Luca; Patanchon, Guillaume; Rex, Marie; Scott, Douglas; Semisch, Christopher; Truch, Matthew D P; Tucker, Carole; Tucker, Gregory S; Viero, Marco P; Wiebe, Donald V

    2011-01-01

    The submillimeter opacity of dust in the diffuse Galactic interstellar medium (ISM) has been quantified using a pixel-by-pixel correlation of images of continuum emission with a proxy for column density. We used three BLAST bands at 250, 350, and 500 \\mu m and one IRAS at 100 \\mu m. The proxy is the near-infrared color excess, E(J-Ks), obtained from 2MASS. Based on observations of stars, we show how well this color excess is correlated with the total hydrogen column density for regions of moderate extinction. The ratio of emission to column density, the emissivity, is then known from the correlations, as a function of frequency. The spectral distribution of this emissivity can be fit by a modified blackbody, whence the characteristic dust temperature T and the desired opacity \\sigma_e(1200) at 1200 GHz can be obtained. We have analyzed 14 regions near the Galactic plane toward the Vela molecular cloud, mostly selected to avoid regions of high column density (N_H > 10^{22} cm^-2) and small enough to ensure a u...

  9. Ice Nuclei in Marine Air: Biogenic Particles or Dust?

    SciTech Connect (OSTI)

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

    2013-01-11

    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.

  10. Modified holographic Ricci dark energy coupled to interacting relativistic and non-relativistic dark matter in the nonflat universe

    E-Print Network [OSTI]

    En-Kun Li; Yu Zhang; Jin-Ling Geng

    2014-12-16

    The modified holographic Ricci dark energy coupled to interacting relativistic and non-relativistic dark matter is considered in the nonflat Friedmann-Robertson-Walker universe. Through examining the deceleration parameter, one can find that the transition time of the Universe from decelerating to accelerating phase in the interacting holographic Ricci dark energy model is close to that in the $\\Lambda$ cold dark matter model. The evolution of modified holographic Ricci dark energy's state parameter and the evolution of dark matter and dark energy's densities shows that the dark energy holds the dominant position from the near past to the future. By studying the statefinder diagnostic and the evolution of the total pressure, one can find that this model could explain the Universe's transition from the radiation to accelerating expansion stage through the dust stage. According to the $Om$ diagnostic, it is easy to find that when the interaction is weak and the proportion of relativistic dark matter in total dark matter is small, this model is phantom-like. Through our studying, we find the interaction and the relativistic dark matter's proportion all have great influence on the evolution of the Universe.

  11. Strongly interacting parton matter equilibration

    SciTech Connect (OSTI)

    Ozvenchuk, V.; Linnyk, O.; Bratkovskaya, E.; Gorenstein, M.; Cassing, W.

    2012-07-15

    We study the kinetic and chemical equilibration in 'infinite' parton matter within the Parton-Hadron-String Dynamics transport approach. The 'infinite' matter is simulated within a cubic box with periodic boundary conditions initialized at different energy densities. Particle abundances, kinetic energy distributions, and the detailed balance of the off-shell quarks and gluons in the strongly-interacting quarkgluon plasma are addressed and discussed.

  12. Dark Matter Triggers of Supernovae

    E-Print Network [OSTI]

    Peter W. Graham; Surjeet Rajendran; Jaime Varela

    2015-05-17

    The transit of primordial black holes through a white dwarf causes localized heating around the trajectory of the black hole through dynamical friction. For sufficiently massive black holes, this heat can initiate runaway thermonuclear fusion causing the white dwarf to explode as a supernova. The shape of the observed distribution of white dwarfs with masses up to $1.25 M_{\\odot}$ rules out primordial black holes with masses $\\sim 10^{19}$ gm - $10^{20}$ gm as a dominant constituent of the local dark matter density. Black holes with masses as large as $10^{24}$ gm will be excluded if recent observations by the NuStar collaboration of a population of white dwarfs near the galactic center are confirmed. Black holes in the mass range $10^{20}$ gm - $10^{22}$ gm are also constrained by the observed supernova rate, though these bounds are subject to astrophysical uncertainties. These bounds can be further strengthened through measurements of white dwarf binaries in gravitational wave observatories. The mechanism proposed in this paper can constrain a variety of other dark matter scenarios such as Q balls, annihilation/collision of large composite states of dark matter and models of dark matter where the accretion of dark matter leads to the formation of compact cores within the star. White dwarfs, with their astronomical lifetimes and sizes, can thus act as large space-time volume detectors enabling a unique probe of the properties of dark matter, especially of dark matter candidates that have low number density. This mechanism also raises the intriguing possibility that a class of supernova may be triggered through rare events induced by dark matter rather than the conventional mechanism of accreting white dwarfs that explode upon reaching the Chandrasekhar mass.

  13. Cosmology, Thermodynamics and Matter Creation

    E-Print Network [OSTI]

    J. A. S. Lima; M. O. Calvao; I. Waga

    2007-08-24

    Several approaches to the matter creation problem in the context of cosmological models are summarily reviewed. A covariant formulation of the general relativistic imperfect simple fluid endowed with a process of matter creation is presented. By considering the standard big bang model, it is shown how the recent results of Prigogine et alii \\cite{1} can be recovered and, at the same time their limits of validity are explicited.

  14. Manure Harvesting Frequency: The Key to Feedyard Dust Control in a Summer Drought 

    E-Print Network [OSTI]

    Auvermann, Brent W.; Parker, David B.; Sweeten, John M.

    2000-11-27

    Summer drought can make dust control in feedyards more challenging than usual. Supplemental water may not keep pace with daily evaporation. The key to dust control is managing the depth of dry manure in the pens by harvesting manure more frequently...

  15. Modeling dust emissions and transport within Europe: The Ukraine March 2007 event

    E-Print Network [OSTI]

    Menut, Laurent

    Modeling dust emissions and transport within Europe: The Ukraine March 2007 event Bertrand originating from Ukraine related to chernozemic-erodible lands. Using surface and satellite measurements in the Netherlands, Belgium, and the north of France were mostly due to the extremely rare Ukraine dust event

  16. Shocks and dust survival in nearby active galaxies: implications for the alignment effect

    E-Print Network [OSTI]

    M. Villar-Martin; D. De Young; A. Alonso-Herrero; M. Allen; L. Binette

    2001-08-21

    One of the most popular explanations for the so-called alignment effect in high redshift (z>0.7) radio galaxies is the scattering by dust of the hidden quasar light. As shown by De Young (1998) a problem with the dust scattering model is that the short destruction time-scale for dust grains means that they will not survive the passage of the radio jet. We investigate the survival of dust in the extended ionised gas of nearby active galaxies with jet/gas interactions. We discuss the implications on the alignment effect of high redshift (>0.7) radio galaxies. We conclude that although shocks are likely to destroy dust grains in regions of interaction, dust might survive in enough quantities to scatter light from the active nucleus and produce alignment between scattered light and the radio structures. We propose an observational test to investigate the existence of dust in shocked regions based on the sensitivity of calcium to depletion onto dust grains.

  17. NANODIAMOND DUST AND THE FAR-ULTRAVIOLET QUASAR BREAK Luc Binette,1

    E-Print Network [OSTI]

    Morisset, Christophe

    NANODIAMOND DUST AND THE FAR-ULTRAVIOLET QUASAR BREAK Luc Binette,1 Gladis Magris C.,2 Yair curve consisting of nanodiamonds, composed of terrestrial cubic diamonds or with surface impurities intrinsic dust model requires a mixture of both cubic diamonds and Allende nanodiamonds and provides

  18. A planetary system as the origin of structure in Fomalhaut's dust belt

    E-Print Network [OSTI]

    Kalas, Paul G.

    A planetary system as the origin of structure in Fomalhaut's dust belt Paul Kalas1 , James R resolution of 0.5 AU. The dust is distributed in a belt 25 AU wide, with a very sharp inner edge at a radial distance of 133 AU, and we measure an offset of 15 AU between the belt's geometric centre and Fomalhaut

  19. Emission of non-thermal microwave radiation by a Martian dust storm Christopher Ruf,1

    E-Print Network [OSTI]

    Ruf, Christopher

    #12;Emission of non-thermal microwave radiation by a Martian dust storm Christopher Ruf,1 Nilton O report evidence for the emission of non-thermal microwave radiation by a deep Martian dust storm, S. Gross, L. Skjerve, and B. Cantor (2009), Emission of non-thermal microwave radiation by a Martian

  20. Temporal controls on global dust emissions: The role of surface S. Engelstaedter1

    E-Print Network [OSTI]

    Washington, Richard

    in the atmosphere will not be realistic either. While climatically important atmospheric gases such as CO2 are well with constraining dust emissions spatially came with the `preferred source' concept following analysis of the firstTemporal controls on global dust emissions: The role of surface gustiness S. Engelstaedter1 and R

  1. ANOMALOUS RADIO EMISSION FROM DUST IN THE HELIX1 S. Casassus,2

    E-Print Network [OSTI]

    Readhead, Anthony

    ANOMALOUS RADIO EMISSION FROM DUST IN THE HELIX1 S. Casassus,2 A. C. S. Readhead,3 T. J. Pearson,3 detection of a new component of foreground Galactic emission. The anomalous foreground at $10­30 GHz, unexplained by tradi- tional emission mechanisms, correlates with 100 m dust emission. We use planetary

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

    E-Print Network [OSTI]

    Duffy, Thomas S.

    . The Raman measurements indicate that the production of carbon dust particles in NSTX involves modifications to be similar to those measured for carbon deposits from atmospheric pressure helium arc discharge responsible for dust production: (i) evap- oration and sublimation of thermally overloaded wall material

  3. Atmospheric Environment 39 (2005) 359369 Dust composition and mixing state inferred from airborne

    E-Print Network [OSTI]

    Clarke, Antony

    2005-01-01

    . Dust-laden air masses that had mixed with urban air pollutants over the Beijing and Tianjin region were and Technology (GIST), Gwangju 500-712, South Korea c Department of Oceanography, University of Hawaii, Honolulu and NO3 À . The results point to an external mixture of mineral dust and urban pollutant particles

  4. A model of the ULF magnetic and electric field generated from a dust devil

    E-Print Network [OSTI]

    Cummer, Steven A.

    A model of the ULF magnetic and electric field generated from a dust devil W. M. Farrell,1 J. R emit ULF magnetic radiation. On Mars, dust devils may also generate such magnetic emissions, which in the vortex wind fields accounts for the magnetic emission. To test this hypothesis in general

  5. DUST FORMATION, EVOLUTION, AND OBSCURATION EFFECTS IN THE VERY HIGH-REDSHIFT UNIVERSE

    SciTech Connect (OSTI)

    Dwek, Eli; Benford, Dominic J. [Observational Cosmology Lab., Code 665, NASA at Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Staguhn, Johannes; Su, Ting [Also at Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA. (United States); Arendt, Richard G. [Also at CRESST, University of Maryland Baltimore County, Baltimore, MD 21250, USA. (United States); Kovacks, Attila, E-mail: eli.dwek@nasa.gov [Also at Astronomy Department, CalTech, Pasadena, CA 90025, USA. (United States)

    2014-06-20

    The evolution of dust at redshifts z ? 9, and consequently the dust properties, differs greatly from that in the local universe. In contrast to the local universe, core collapse supernovae (CCSNe) are the only source of thermally condensed dust. Because of the low initial dust-to-gas mass ratio, grain destruction rates are low, so that CCSNe are net producers of interstellar dust. Galaxies with large initial gas mass or high mass infall rate will therefore have a more rapid net rate of dust production compared to galaxies with lower gas mass, even at the same star formation rate. The dust composition is dominated by silicates, which exhibit a strong rise in the UV opacity near the Lyman break. This ''silicate-UV break'' may be confused with the Lyman break, resulting in a misidentification of a galaxy's photometric redshift. In this Letter we demonstrate these effects by analyzing the spectral energy distribution of MACS1149-JD, a lensed galaxy at z = 9.6. A potential 2 mm counterpart of MACS1149-JD has been identified with GISMO. While additional observations are required to corroborate this identification, we use this possible association to illustrate the physical processes and the observational effects of dust in the very high-redshift universe.

  6. Study on plasma parameters and dust charging in an electrostatically plugged multicusp plasma device

    SciTech Connect (OSTI)

    Kakati, B.; 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)

    2011-06-15

    The effect of the electrostatic confinement potential on the charging of dust grains and its relationship with the plasma parameters has been studied in an electrostatically plugged multicusp dusty plasma device. Electrostatic plugging is implemented by biasing the electrically isolated magnetic multicusp channel walls. The experimental results show that voltage applied to the channel walls can be a controlling parameter for dust charging.

  7. Mixtures of pollution, dust, sea salt, and volcanic aerosol during ACE-Asia: Radiative properties

    E-Print Network [OSTI]

    was dominated by marine, polluted, volcanic, and dust aerosols. Average total light scattering coefficients (sspMixtures of pollution, dust, sea salt, and volcanic aerosol during ACE-Asia: Radiative properties). Aerosol hygroscopicity ranged from deliquescent with hysteresis (marine frequently and polluted variably

  8. The global distribution of mineral dust and its impacts on the climate system: A review

    E-Print Network [OSTI]

    Hickman, Mark

    The global distribution of mineral dust and its impacts on the climate system: A review O. Alizadeh Received in revised form 5 November 2013 Accepted 6 November 2013 Available online 20 November 2013 Mineral. Current understanding of spatial and temporal variations of mineral dust, as well as its impacts

  9. www.sea.co.uk a Cohort plc company L-DAP Lunar Dust Analysis Package

    E-Print Network [OSTI]

    Anand, Mahesh

    www.sea.co.uk a Cohort plc company L-DAP Lunar Dust Analysis Package Study Overview ESTEC Contract.sea.co.uk a Cohort plc company Dust Problems.. · "I think probably the most aggravating, restricting facets of lunar #12;www.sea.co.uk a Cohort plc company Lunar South Pole ... L-DAP Overview 28th Oct 2011 · South Pole

  10. CORRESPONDENCE Reply to: African dust and asthma in the Caribbean--medical

    E-Print Network [OSTI]

    Prospero, Joseph M.

    to African dust and to Barbados and the Caribbean. Rather, they cite much literature on the relationship over the oceans and their role in climate, a program that began in 1965 on Barbados and continues impact of climate variability on dust concentrations in Barbados trade winds. With the onset of long

  11. THE DUST RING OF LUMINOUS BLUE VARIABLE CANDIDATE HD 168625: INFRARED OBSERVATIONS AND MODEL CALCULATIONS1

    E-Print Network [OSTI]

    Speck, Angela Karen

    THE DUST RING OF LUMINOUS BLUE VARIABLE CANDIDATE HD 168625: INFRARED OBSERVATIONS AND MODEL surrounding the luminous blue variable (LBV) candidate HD 168625, together with new temperature and optical energy distribution of the dust. Therefore, HD 168625 is an excellent example of proposed models of LBV

  12. Detecting nanoparticles at radio frequencies: Jovian dust stream impacts on Cassini/RPWS

    E-Print Network [OSTI]

    Gurnett, Donald A.

    performed during the Jovian fly-by, when the on-board dust analyser recorded dust streams which were interpreted as nanoparticles moving at about the solar wind speed. The observed wave pulses are produced motional electric field at 1 AU, with the STEREO/WAVES instrument [Meyer-Vernet et al., 2008]. [3] When

  13. RAPID DUST FORMATION IN NOVAE: THE SPEED CLASS—FORMATION TIMESCALE CORRELATION EXPLAINED

    SciTech Connect (OSTI)

    Williams, S. C.; Bode, M. F.; Darnley, M. J.; Evans, A.; Zubko, V.; Shafter, A. W.

    2013-11-10

    Observations show that the time of onset of dust formation in classical novae depends strongly on their speed class, with dust typically taking longer to form in slower novae. Using empirical relationships between speed class, luminosity and ejection velocity, it can be shown that dust formation timescale is expected to be essentially independent of speed class. However, following a nova outburst the spectrum of the central hot source evolves, with an increasing proportion of the radiation being emitted short-ward of the Lyman limit. The rate at which the spectrum evolves also depends on the speed class. We have therefore refined the simple model by assuming photons at energies higher than the Lyman limit are absorbed by neutral hydrogen gas internal to the dust formation sites, therefore preventing these photons reaching the nucleation sites. With this refinement the dust formation timescale is theoretically dependent on speed class and the results of our theoretical modification agree well with the observational data. We consider two types of carbon-based dust, graphite and amorphous carbon, with both types producing similar relationships. Our results can be used to predict when dust will form in a nova of a given speed class and hence when observations should optimally be taken to detect the onset of dust formation.

  14. 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]

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

    2013-06-11

    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.

  15. DUST AND GAS IN THE MAGELLANIC CLOUDS FROM THE HERITAGE HERSCHEL KEY PROJECT. I. DUST PROPERTIES AND INSIGHTS INTO THE ORIGIN OF THE SUBMILLIMETER EXCESS EMISSION

    SciTech Connect (OSTI)

    Gordon, Karl D.; Roman-Duval, Julia; Meixner, Margaret; Bot, Caroline; Babler, Brian; Bernard, Jean-Philippe; Bolatto, Alberto; Jameson, Katherine; Boyer, Martha L.; Clayton, Geoffrey C.; Engelbracht, Charles; Fukui, Yasuo; Galametz, Maud; Galliano, Frederic; Hony, Sacha; Lebouteiller, Vianney; Indebetouw, Remy; Israel, Frank P.; Kawamura, Akiko; and others

    2014-12-20

    The dust properties in the Large and Small Magellanic clouds (LMC/SMC) are studied using the HERITAGE Herschel Key Project photometric data in five bands from 100 to 500 ?m. Three simple models of dust emission were fit to the observations: a single temperature blackbody modified by a power-law emissivity (SMBB), a single temperature blackbody modified by a broken power-law emissivity (BEMBB), and two blackbodies with different temperatures, both modified by the same power-law emissivity (TTMBB). Using these models, we investigate the origin of the submillimeter excess, defined as the submillimeter emission above that expected from SMBB models fit to observations <200 ?m. We find that the BEMBB model produces the lowest fit residuals with pixel-averaged 500 ?m submillimeter excesses of 27% and 43% for the LMC and SMC, respectively. Adopting gas masses from previous works, the gas-to-dust ratios calculated from our fitting results show that the TTMBB fits require significantly more dust than are available even if all the metals present in the interstellar medium (ISM) were condensed into dust. This indicates that the submillimeter excess is more likely to be due to emissivity variations than a second population of colder dust. We derive integrated dust masses of (7.3 ± 1.7) × 10{sup 5} and (8.3 ± 2.1) × 10{sup 4} M {sub ?} for the LMC and SMC, respectively. We find significant correlations between the submillimeter excess and other dust properties; further work is needed to determine the relative contributions of fitting noise and ISM physics to the correlations.

  16. A deep high-resolution optical log of dust, ash, and stratigraphy in South Pole glacial ice

    E-Print Network [OSTI]

    Woschnagg, Kurt

    A deep high-resolution optical log of dust, ash, and stratigraphy in South Pole glacial ice N. E (2005), A deep high-resolution optical log of dust, ash, and stratigraphy in South Pole glacial ice

  17. A joint analysis of Planck and BICEP2 B modes including dust polarization uncertainty

    SciTech Connect (OSTI)

    Mortonson, Michael J.; Seljak, Uroš E-mail: useljak@berkeley.edu

    2014-10-01

    We analyze BICEP2 and Planck data using a model that includes CMB lensing, gravity waves, and polarized dust. Recently published Planck dust polarization maps have highlighted the difficulty of estimating the amount of dust polarization in low intensity regions, suggesting that the polarization fractions have considerable uncertainties and may be significantly higher than previous predictions. In this paper, we start by assuming nothing about the dust polarization except for the power spectrum shape, which we take to be C{sub l}{sup BB,dust} ? l{sup -2.42}. The resulting joint BICEP2+Planck analysis favors solutions without gravity waves, and the upper limit on the tensor-to-scalar ratio is r<0.11, a slight improvement relative to the Planck analysis alone which gives r<0.13 (95% c.l.). The estimated amplitude of the dust polarization power spectrum agrees with expectations for this field based on both HI column density and Planck polarization measurements at 353 GHz in the BICEP2 field. Including the latter constraint on the dust spectrum amplitude in our analysis improves the limit further to r < 0.09, placing strong constraints on theories of inflation (e.g., models with r>0.14 are excluded with 99.5% confidence). We address the cross-correlation analysis of BICEP2 at 150 GHz with BICEP1 at 100 GHz as a test of foreground contamination. We find that the null hypothesis of dust and lensing with 0r= gives ? ?{sup 2} < 2 relative to the hypothesis of no dust, so the frequency analysis does not strongly favor either model over the other. We also discuss how more accurate dust polarization maps may improve our constraints. If the dust polarization is measured perfectly, the limit can reach r < 0.05 (or the corresponding detection significance if the observed dust signal plus the expected lensing signal is below the BICEP2 observations), but this degrades quickly to almost no improvement if the dust calibration error is 20% or larger or if the dust maps are not processed through the BICEP2 pipeline, inducing sampling variance noise.

  18. Nonlinear dust acoustic waves in a mixed nonthermal high energy-tail electron distribution

    SciTech Connect (OSTI)

    Younsi, Smain; Tribeche, Mouloud

    2008-07-15

    Large amplitude as well as weakly nonlinear dust acoustic waves in a mixed nonthermal high-energy-tail electron distribution are investigated. The effects of charge variation and electron deviation from Boltzmann distribution on the large amplitude dust acoustic soliton are then considered. The dust charge variation leads to an additional enlargement of the dust acoustic soliton, which is more pronounced as the electrons evolve far away from Maxwell-Boltzmann distribution. Under certain conditions, the dust charge fluctuation may provide an alternate physical mechanism causing anomalous dissipation, the strength of which becomes important and may prevail over that of dispersion as the suprathermal character of the plasma becomes important. The results complement and provide new insights into our previously published results on this problem [K. Aoutou, M. Tribeche, and T. H. Zerguini, Phys. Plasmas 15, 013702 (2008)].

  19. Fragmentation and Evolution of Molecular Clouds. II: The Effect of Dust Heating

    E-Print Network [OSTI]

    Urban, Andrea; Evans, Neal J

    2009-01-01

    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 Msun and 671 Msun, using these two different energetics algorithms. The mass functions for the isothermal simulations and simulations which include dust heating are drastically different. In the isothermal simulation, we do not form any objects with masses above 1 Msun. However, the simulation with dust heating, while missing some of the low-mass objects, forms high-mass objects (~20 Msun) which have a distribution similar to the Salpeter IMF. The envelope density profiles around the stars formed in our simulation match observed values around isolated, l...

  20. On vapor shielding of dust grains of iron, molybdenum, and tungsten in fusion plasmas

    SciTech Connect (OSTI)

    Brown, B. T.; Smirnov, R. D., E-mail: rsmirnov@ucsd.edu; Krasheninnikov, S. I. [Department of Mechanical and Aerospace Engineering, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093-0411 (United States)] [Department of Mechanical and Aerospace Engineering, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093-0411 (United States)

    2014-02-15

    The shielding effects of ablation cloud around a small dust grain composed of iron, molybdenum, or tungsten in fusion plasmas are considered. These include collisional dissipation of momentum flux of impinging plasma ions, heat transfer by secondary plasma created due to electron impact ionization of the ablated atoms, and radiative plasma power losses in the ablation cloud. The maximum radius, which limits applicability of existing dust-plasma interaction models neglecting the cloud shielding effects, for dust grains of the considered high-Z metals is calculated as function of plasma parameters. The thermal bifurcation triggered by thermionic electron emission from dust grains, observed for some of the considered materials, is analyzed. The results are compared with previous calculations for dust composed of low-Z fusion related materials, i.e., lithium, beryllium, and carbon.

  1. PROBING DENSE NUCLEAR MATTER VIA NUCLEAR COLLISIONS

    E-Print Network [OSTI]

    Stocker, H.

    2012-01-01

    shocked nuclear matter during the compression and expansionand isentropic expansion were valid in nuclear collisions.

  2. THE PHYSICS OF PROTOPLANETESIMAL DUST AGGLOMERATES. VII. THE LOW-VELOCITY COLLISION BEHAVIOR OF LARGE DUST AGGLOMERATES

    SciTech Connect (OSTI)

    Schraepler, Rainer; Blum, Juergen; Seizinger, Alexander; Kley, Wilhelm

    2012-10-10

    We performed micro-gravity collision experiments in our laboratory drop tower using 5 cm sized dust agglomerates with volume filling factors of 0.3 and 0.4, respectively. This work is an extension of our previous experiments reported in Beitz et al. to aggregates of more than one order of magnitude higher masses. The dust aggregates consisted of micrometer-sized silica particles and were macroscopically homogeneous. We measured the coefficient of restitution for collision velocities ranging from 1 cm s{sup -1} to 0.5 m s{sup -1}, and determined the fragmentation velocity. For low velocities, the coefficient of restitution decreases with increasing impact velocity, in contrast to findings by Beitz et al. At higher velocities, the value of the coefficient of restitution becomes constant, before the aggregates break at the onset of fragmentation. We interpret the qualitative change in the coefficient of restitution as the transition from a solid-body-dominated to a granular-medium-dominated behavior. We complement our experiments by molecular-dynamics simulations of porous aggregates and obtain a reasonable match to the experimental data. We discuss the importance of our experiments for protoplanetary disks, debris disks, and planetary rings. This work is an extension to the previous work of our group and gives new insight into the velocity dependency of the coefficient of restitution due to improved measurements, better statistics, and a theoretical approach.

  3. DUST AND GAS IN THE MAGELLANIC CLOUDS FROM THE HERITAGE HERSCHEL KEY PROJECT. II. GAS-TO-DUST RATIO VARIATIONS ACROSS INTERSTELLAR MEDIUM PHASES

    SciTech Connect (OSTI)

    Roman-Duval, Julia; Gordon, Karl D.; Meixner, Margaret; Bot, Caroline; Bolatto, Alberto; Jameson, Katherine; Hughes, Annie; Hony, Sacha; Wong, Tony; Babler, Brian; Bernard, Jean-Philippe; Clayton, Geoffrey C.; Fukui, Yasuo; Galametz, Maud; Galliano, Frederic; Lebouteiller, Vianney; Lee, Min-Young; Israel, Frank; Li, Aigen; and others

    2014-12-20

    The spatial variations of the gas-to-dust ratio (GDR) provide constraints on the chemical evolution and lifecycle of dust in galaxies. We examine the relation between dust and gas at 10-50 pc resolution in the Large and Small Magellanic Clouds (LMC and SMC) based on Herschel far-infrared (FIR), H I 21 cm, CO, and H? observations. In the diffuse atomic interstellar medium (ISM), we derive the GDR as the slope of the dust-gas relation and find GDRs of 380{sub ?130}{sup +250} ± 3 in the LMC, and 1200{sub ?420}{sup +1600} ± 120 in the SMC, not including helium. The atomic-to-molecular transition is located at dust surface densities of 0.05 M {sub ?} pc{sup –2} in the LMC and 0.03 M {sub ?} pc{sup –2} in the SMC, corresponding to A {sub V} ? 0.4 and 0.2, respectively. We investigate the range of CO-to-H{sub 2} conversion factor to best account for all the molecular gas in the beam of the observations, and find upper limits on X {sub CO} to be 6 × 10{sup 20} cm{sup –2} K{sup –1} km{sup –1} s in the LMC (Z = 0.5 Z {sub ?}) at 15 pc resolution, and 4 × 10{sup 21} cm{sup –2} K{sup –1} km{sup –1} s in the SMC (Z = 0.2 Z {sub ?}) at 45 pc resolution. In the LMC, the slope of the dust-gas relation in the dense ISM is lower than in the diffuse ISM by a factor ?2, even after accounting for the effects of CO-dark H{sub 2} in the translucent envelopes of molecular clouds. Coagulation of dust grains and the subsequent dust emissivity increase in molecular clouds, and/or accretion of gas-phase metals onto dust grains, and the subsequent dust abundance (dust-to-gas ratio) increase in molecular clouds could explain the observations. In the SMC, variations in the dust-gas slope caused by coagulation or accretion are degenerate with the effects of CO-dark H{sub 2}. Within the expected 5-20 times Galactic X {sub CO} range, the dust-gas slope can be either constant or decrease by a factor of several across ISM phases. Further modeling and observations are required to break the degeneracy between dust grain coagulation, accretion, and CO-dark H{sub 2}. Our analysis demonstrates that obtaining robust ISM masses remains a non-trivial endeavor even in the local Universe using state-of-the-art maps of thermal dust emission.

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

    SciTech Connect (OSTI)

    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)

    2013-10-10

    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.

  5. Sensitivity of population smoke exposure to fire locations in Equatorial Asia1 Patrick S. Kim1,*

    E-Print Network [OSTI]

    Mickley, Loretta J.

    , Fire, Conservation, Population-Exposure52 53 1. Introduction54 55 Global palm oil and Malaysia together account for 86% of the57 world's production and Indonesia plans to double its output for conversion to32 oil palm plantations, can lead to high smoke concentrations across this densely populated

  6. Efficacies of dexfenfluramine and fluoxetine in preventing weight gain after smoking cessation 1-4

    E-Print Network [OSTI]

    Wurtman, Richard

    in metabolism and energy intake both appear to change energy balance. Some findings suggest that quitting metabolic rate (9), Heightened energy intake probably makes a larger contribution to weight gain, because energy intake increases by "'627-1463 kJ (150-350 kcal)/d after smoking cessation (I, 10-12). Energy

  7. Development and validation of a Spanish version of the Questionnaire of Smoking Urges 

    E-Print Network [OSTI]

    Henry, Keisha Denythia

    2001-01-01

    I wanted to examine whether the factor structure of the Questionnaire of Smoking Urges (QSU; Tiffany & Drobes, 1991) was best represented by a one, two, or four-factor structure in two culturally distinct samples of smokers from Spain and the U...

  8. Plutonium-238 observations as a test of modeled transport and surface deposition of meteoric smoke particles

    E-Print Network [OSTI]

    Chipperfield, Martyn

    Plutonium-238 observations as a test of modeled transport and surface deposition of meteoric smoke chemistry-climate model (CCM) to simulate the transport and deposition of plutonium- 238 oxide nanoparticles. P. Chipperfield, and J. M. C. Plane (2013), Plutonium-238 observations as a test of modeled

  9. Author's personal copy On stairwell and elevator shaft pressurization for smoke control

    E-Print Network [OSTI]

    Miller, Richard S.

    Author's personal copy On stairwell and elevator shaft pressurization for smoke control in tall Stairwell pressurization Elevator pressurization a b s t r a c t Elevator shaft and stairwell shaft is found to be completely feasible in the absence of elevator shaft pressurization. In contrast, coupled

  10. Carbon loading of alveolar macrophages in adults and children exposed to biomass smoke particles

    E-Print Network [OSTI]

    Banaji,. Murad

    Carbon loading of alveolar macrophages in adults and children exposed to biomass smoke particles morbidity in both women and children in the developing world. However, the amount of carbon reaching lower aimed to compare AM carbon loading in women and children exposed to biomass PM in Gondar, Ethiopia

  11. Search for Phobos and Deimos gas/dust tori using in situ observations from Mars Global Surveyor MAG/ER

    E-Print Network [OSTI]

    California at Berkeley, University of

    outgassing or dust escape from the martian moons. Of the 1246 magnetic field perturbation events found causes than outgassing/dust escape from the martian moons. Thus we conclude that the amount of gas for outgassing or dust escape from the martian moons. Ó 2009 Elsevier Inc. All rights reserved. 1. Introduction

  12. Diffraction of dust acoustic waves by a circular cylinder S.-H. Kim, J. R. Heinrich, and R. L. Merlinoa

    E-Print Network [OSTI]

    Merlino, Robert L.

    Diffraction of dust acoustic waves by a circular cylinder S.-H. Kim, J. R. Heinrich, and R. L, 1896 . © 2008 American Institute of Physics. DOI: 10.1063/1.2977986 Dust acoustic DA waves are pressure July 2008; accepted 14 August 2008; published online 23 September 2008 The diffraction of dust acoustic

  13. Simulation of the shielding of dust particles in low pressure glow Seung J. Choi and Mark J. Kushner

    E-Print Network [OSTI]

    Kushner, Mark

    Simulation of the shielding of dust particles in low pressure glow discharges Seung J. Choi) The dynamics of the shielding of particulates ("dust") in low pressure glow discharges have been investigated sections represented by the geometrical obscuration of the charged dust particles and their shield- ing

  14. Window in the dark matter exclusion limits

    SciTech Connect (OSTI)

    Zaharijas, Gabrijela; Farrar, Glennys R. [Center for Cosmology and Particle Physics, New York University, New York, New York 10003 (United States)

    2005-10-15

    We consider the cross section limits for light dark matter cadnidates (m=0.4 to 10 GeV). We calculate the interaction of dark matter in the crust above underground dark matter detectors and find that in the intermediate cross section range, the energy loss of dark matter is sufficient to fall below the energy threshold of current underground experiments. This implies the existence of a window in the dark matter exclusion limits in the micro-barn range.

  15. Double-Disk Dark Matter

    E-Print Network [OSTI]

    JiJi Fan; Andrey Katz; Lisa Randall; Matthew Reece

    2013-07-31

    Based on observational constraints on large scale structure and halo structure, dark matter is generally taken to be cold and essentially collisionless. On the other hand, given the large number of particles and forces in the visible world, a more complex dark sector could be a reasonable or even likely possibility. This hypothesis leads to testable consequences, perhaps portending the discovery of a rich hidden world neighboring our own. We consider a scenario that readily satisfies current bounds that we call Partially Interacting Dark Matter (PIDM). This scenario contains self-interacting dark matter, but it is not the dominant component. Even if PIDM contains only a fraction of the net dark matter density, comparable to the baryonic fraction, the subdominant component's interactions can lead to interesting and potentially observable consequences. Our primary focus will be the special case of Double-Disk Dark Matter (DDDM), in which self-interactions allow the dark matter to lose enough energy to lead to dynamics similar to those in the baryonic sector. We explore a simple model in which DDDM can cool efficiently and form a disk within galaxies, and we evaluate some of the possible observational signatures. The most prominent signal of such a scenario could be an enhanced indirect detection signature with a distinctive spatial distribution. Even though subdominant, the enhanced density at the center of the galaxy and possibly throughout the plane of the galaxy can lead to large boost factors, and could even explain a signature as large as the 130 GeV Fermi line. Such scenarios also predict additional dark radiation degrees of freedom that could soon be detectable and would influence the interpretation of future data, such as that from Planck and from the Gaia satellite. We consider this to be the first step toward exploring a rich array of new possibilities for dark matter dynamics.

  16. Generator, mechanical, smoke: For dual-purpose unit, XM56, Yuma Proving Ground, Yuma, Arizona

    SciTech Connect (OSTI)

    Driver, C.J.; Ligotke, M.W.; Moore, E.B. Jr. (Pacific Northwest Lab., Richland, WA (United States)); Bowers, J.F. (Dugway Proving Ground, UT (United States))

    1991-10-01

    The US Army Chemical Research, Development and Engineering Center (CRDEC) is planning to perform a field test of the XM56 smoke generator at the US Army Yuma Proving Ground (YPG), Arizona. The XM56, enabling the use of fog oil in combination with other materials, such as graphite flakes, is part of an effort to improve the efficiency of smoke generation and to extend the effectiveness of the resulting obscurant cloud to include the infrared spectrum. The plan field operation includes a road test and concurrent smoke- generation trials. Three M1037 vehicles with operation XM56 generators will be road-tested for 100 h. Smoke will be generated for 30 min from a single stationary XM56 four times during the road test, resulting in a total of 120 min of smoke generation. The total aerial release of obscurant materials during this test is expected to be 556 kg (1,220 lb) of fog oil and 547 kg (1,200 lb) of graphite flakes. This environmental assessment has evaluated the consequences of the proposed action. Air concentrations and surface deposition levels were estimated using an atmospheric dispersion model. Degradation of fog oil and incorporation of graphite in the soil column will limit the residual impacts of the planned action. No significant impacts to air, water, and soil quality are anticipated. risks to the environment posed by the proposed action were determined to be minimal or below levels previously found to pose measurable impacts. Cultural resources are present on YPG and have been identified in adjacent areas; therefore, off-road activities should be preceded by a cultural resource survey. A Finding of No Significant Impact is recommended. 61 refs., 1 fig.

  17. Bimetric gravity and dark matter

    E-Print Network [OSTI]

    Laura Bernard; Luc Blanchet; Lavinia Heisenberg

    2015-07-10

    We review some recent proposals for relativistic models of dark matter in the context of bimetric gravity. The aim is to solve the problems of cold dark matter (CDM) at galactic scales, and to reproduce the phenomenology of the modified Newtonian dynamics (MOND), while still being in agreement with the standard cosmological model $\\Lambda$-CDM at large scales. In this context a promising alternative is dipolar dark matter (DDM) in which two different species of dark matter particles are separately coupled to the two metrics of bigravity and are linked together by an internal vector field. The phenomenology of MOND then results from a mechanism of gravitational polarization. Probably the best formulation of the model is within the framework of recently developed massive bigravity theories. Then the gravitational sector of the model is safe by construction, but a ghostly degree of freedom in the decoupling limit is still present in the dark matter sector. Future work should analyse the cosmological solutions of the model and check the post-Newtonian parameters in the solar system.

  18. Gravitational collapse of thin shells of dust in Shape Dynamics

    E-Print Network [OSTI]

    Gomes, Henrique; Mercati, Flavio; Napoletano, Andrea

    2015-01-01

    Shape dynamics is a theory of gravity whose physical configuration space is composed of spatial conformal equivalence classes of 3-dimensional geometries. This physical configuration space is not a priori related to the one given by 4-dimensional space-time geometries, familiar to general relativists. Although one can largely match dynamical solutions arising in each theory, this is not always the case. One expects such differences in collapse situations that lead to the formation of black holes. In this paper we study spherical collapse of thin-shells of pressureless dust as a fully back-reacting dynamical system, in a context related to both shape dynamics and general relativity in ADM form in Constant Mean Curvature (CMC) gauge -- the particular time slicing where any correspondence between ADM and shape dynamics is manifest. To better accommodate the relational setting of shape dynamics, we also begin a study of collapse of two such shells in a compact Universe.

  19. Numerical determination of the material properties of porous dust cakes

    E-Print Network [OSTI]

    D. Paszun; C. Dominik

    2008-02-13

    The formation of planetesimals requires the growth of dust particles through collisions. Micron-sized particles must grow by many orders of magnitude in mass. In order to understand and model the processes during this growth, the mechanical properties, and the interaction cross sections of aggregates with surrounding gas must be well understood. Recent advances in experimental (laboratory) studies now provide the background for pushing numerical aggregate models onto a new level. We present the calibration of a previously tested model of aggregate dynamics. We use plastic deformation of surface asperities as the physical model to bring critical velocities for sticking into accordance with experimental results. The modified code is then used to compute compression strength and the velocity of sound in the aggregate at different densities. We compare these predictions with experimental results and conclude that the new code is capable of studying the properties of small aggregates.

  20. Energy conservation in electrostatic fabric filtration of industrial dust

    SciTech Connect (OSTI)

    Ariman, T.

    1981-12-01

    Conservation in energy consumption in industrial fabric filtration systems has become very important due to the substantial increase in energy costs. Recently, an external electric field was utilized in the industrial dust control by fabric filters with very promising initial results. A substantial decrease in the pressure drop and an increase in collection efficiency were observed. The detailed outcome of the experimental research program in electrostatic fabric filtration was presented. The results show that pressure drop decreases substantially with the increased electrostatic field strength for all relevant parameters. Furthermore, the data of the experimental program was utilized to develop a semi-empirical model for the determination of the pressure drop and to establish an Energy-Optimized Design Criteria.

  1. The COMPLETE Nature of the Warm Dust Ring in Perseus

    E-Print Network [OSTI]

    Naomi A. Ridge; Scott L. Schnee; Alyssa A. Goodman; Jonathan B. Foster

    2006-01-30

    The Perseus molecular cloud complex is a ~30pc long chain of molecular clouds most well-known for the two star-forming clusters NGC1333 and IC348 and the well-studied outflow source in B5. However, when studied at mid- to far-infrared wavelengths the region is dominated by a ~10pc diameter shell of warm dust, likely generated by an HII region caused by the early B-star HD278942. Using a revised calibration technique the COMPLETE team has produced high-sensitivity temperature and column-density maps of the Perseus region from IRAS Sky Survey Atlas (ISSA) 60 and 100um data. In this paper, we combine the ISSA based dust-emission maps with other observations collected as part of the COMPLETE Survey, along with archival H-alpha and MSX observations. Molecular line observations from FCRAO and extinction maps constructed by applying the NICER method to the 2MASS catalog provide independent estimates of the ``true'' column-density of the shell. H-alpha emission in the region of the shell confirms that it is most likely an HII region located behind the cloud complex, and 8um data from MSX indicates that the shell may be interacting with the cloud. Finally, the two polarisation components previously seen towards background stars in the region can be explained by the association of the stronger component with the shell. If confirmed, this would be the first observation of a parsec-scale swept-up magnetic field.

  2. Moment equations for chemical reactions on interstellar dust grains

    E-Print Network [OSTI]

    Azi Lipshtat; Ofer Biham

    2002-12-09

    While most chemical reactions in the interstellar medium take place in the gas phase, those occurring on the surfaces of dust grains play an essential role. Chemical models based on rate equations including both gas phase and grain surface reactions have been used in order to simulate the formation of chemical complexity in interstellar clouds. For reactions in the gas phase and on large grains, rate equations, which are highly efficient to simulate, are an ideal tool. However, for small grains under low flux, the typical number of atoms or molecules of certain reactive species on a grain may go down to order one or less. In this case the discrete nature of the opulations of reactive species as well as the fluctuations become dominant, thus the mean-field approximation on which the rate equations are based does not apply. Recently, a master equation approach, that provides a good description of chemical reactions on interstellar dust grains, was proposed. Here we present a related approach based on moment equations that can be obtained from the master equation. These equations describe the time evolution of the moments of the distribution of the population of the various chemical species on the grain. An advantage of this approach is the fact that the production rates of molecular species are expressed directly in terms of these moments. Here we use the moment equations to calculate the rate of molecular hydrogen formation on small grains. It is shown that the moment equation approach is efficient in this case in which only a single reactive specie is involved. The set of equations for the case of two species is presented and the difficulties in implementing this approach for complex reaction networks involving multiple species are discussed.

  3. El Roque de Los Muchachos Site Characteristics. III. Analysis of Atmospheric Dust and Aerosol Extinction

    E-Print Network [OSTI]

    Lombardi, G; Ortolani, S; Pedani, M; Ghedina, A

    2008-01-01

    Canary Islands are normally interested by dominant North-East winds that, in some meteorological conditions, can transport sand at high altitude from the Sahara desert. The dust may affect the efficiency of the telescopes and decreases the transparency of the sky. In order to maximize the scientific return of the telescopes located at the ORM, we present an analysis of the atmospheric dust content and its effects on astronomical observations. B, V and I dust aerosol astronomical extinction are derived. Using a 5 years series database of data taken from the four channel TNG dust monitor, we compute a mean hourly and daily values of the dust content. We have detected particles having size 0.3, 0.5, 1.0 and 5.0 um. Using a power law we have derived the content of 10.0 um particles. We found a typical local dust concentration ranging from 3x10^6 particles per cubic meter at 0.3 um, to 10^3 at 5.0 um and 10 at 10.0 um, increasing up to 3 order of magnitudes during the dust storms, with a relative higher increase o...

  4. Effect of confining wall potential on charged collimated dust beam in low-pressure plasma

    SciTech Connect (OSTI)

    Kausik, S. S.; Kakati, B.; Saikia, B. K. [Centre of Plasma Physics, Institute for Plasma Research, Sonapur 782 402 (India)] [Centre of Plasma Physics, Institute for Plasma Research, Sonapur 782 402 (India)

    2013-05-15

    The effect of confining wall potential on charged collimated dust beam in low-pressure plasma has been studied in a dusty plasma experimental setup by applying electrostatic field to each channel of a multicusp magnetic cage. Argon plasma is produced by hot cathode discharge method at a pressure of 5×10{sup ?4} millibars and is confined by a full line cusped magnetic field confinement system. Silver dust grains are produced by gas-evaporation technique and move upward in the form of a collimated dust beam due to differential pressure maintained between the dust and plasma chambers. The charged grains in the beam after coming out from the plasma column enter into the diagnostic chamber and are deflected by a dc field applied across a pair of deflector plates at different confining potentials. Both from the amount of deflection and the floating potential, the number of charges collected by the dust grains is calculated. Furthermore, the collimated dust beam strikes the Faraday cup, which is placed above the deflector plates, and the current (?pA) so produced is measured by an electrometer at different confining potentials. The experimental results demonstrate the significant effect of confining wall potential on charging of dust grains.

  5. Concurrent Formation of Carbon and Silicate Dust in Nova V1280 Sco

    E-Print Network [OSTI]

    Sakon, Itsuki; Onaka, Takashi; Nozawa, Takaya; Kimura, Yuki; Fujiyoshi, Takuya; Shimonishi, Takashi; Usui, Fumihiko; Takahashi, Hidenori; Ohsawa, Ryou; Arai, Akira; Uemura, Makoto; Nagayama, Takahiro; Koo, Bon-Chul; Kozasa, Takashi

    2015-01-01

    We present infrared multi-epoch observations of the dust forming nova V1280 Sco over $\\sim$2000 days from the outburst. The temporal evolution of the infrared spectral energy distributions at 1272, 1616 and 1947 days can be explained by the emissions produced by amorphous carbon dust of mass (6.6--8.7)$\\times$10$^{-8}$M$_{\\odot}$ with a representative grain size of 0.01$~\\mu$m and astronomical silicate dust of mass (3.4--4.3)$\\times$10$^{-7}$M$_{\\odot}$ with a representative grain size of 0.3--0.5$~\\mu$m. Both of these dust species travel farther away from the white dwarf without an apparent mass evolution throughout those later epochs. The dust formation scenario around V1280 Sco suggested from our analyses is that the amorphous carbon dust is formed in the nova ejecta followed by the formation of silicate dust in the expanding nova ejecta or as a result of the interaction between the nova wind and the circumstellar medium.

  6. The DAMIC dark matter experiment

    E-Print Network [OSTI]

    Aguilar-Arevalo, A; Bertou, X; Bole, D; Butner, M; Cancelo, G; Vázquez, A Castañeda; Chavarria, A E; Neto, J R T de Mello; Dixon, S; D'Olivo, J C; Estrada, J; Moroni, G Fernandez; Torres, K P Hernández; Izraelevitch, F; Kavner, A; Kilminster, B; Lawson, I; Liao, J; López, M; Molina, J; Moreno-Granados, G; Pena, J; Privitera, P; Sarkis, Y; Scarpine, V; Schwarz, T; Haro, M Sofo; Tiffenberg, J; Machado, D Torres; Trillaud, F; You, X; Zhou, J

    2015-01-01

    The DAMIC (Dark Matter in CCDs) experiment uses high resistivity, scientific grade CCDs to search for dark matter. The CCD's low electronic noise allows an unprecedently low energy threshold of a few tens of eV that make it possible to detect silicon recoils resulting from interactions of low mass WIMPs. In addition the CCD's high spatial resolution and the excellent energy response results in very effective background identification techniques. The experiment has a unique sensitivity to dark matter particles with masses below 10 GeV/c$^2$. Previous results have demonstrated the potential of this technology, motivating the construction of DAMIC100, a 100 grams silicon target detector currently being installed at SNOLAB. In this contribution, the mode of operation and unique imaging capabilities of the CCDs, and how they may be exploited to characterize and suppress backgrounds will be discussed, as well as physics results after one year of data taking.

  7. Dark Matter in 3D

    SciTech Connect (OSTI)

    Alves, Daniele S.M.; Hedri, Sonia El; Wacker, Jay G.

    2012-04-01

    We discuss the relevance of directional detection experiments in the post-discovery era and propose a method to extract the local dark matter phase space distribution from directional data. The first feature of this method is a parameterization of the dark matter distribution function in terms of integrals of motion, which can be analytically extended to infer properties of the global distribution if certain equilibrium conditions hold. The second feature of our method is a decomposition of the distribution function in moments of a model independent basis, with minimal reliance on the ansatz for its functional form. We illustrate our method using the Via Lactea II N-body simulation as well as an analytical model for the dark matter halo. We conclude that O(1000) events are necessary to measure deviations from the Standard Halo Model and constrain or measure the presence of anisotropies.

  8. Static Response of Neutron Matter

    E-Print Network [OSTI]

    Buraczynski, Mateusz

    2015-01-01

    We generalize the problem of strongly interacting neutron matter by adding a periodic external modulation. This allows us to study from first principles a neutron system that is extended and inhomogeneous, with connections to the physics of both neutron-star crusts and neutron-rich nuclei. We carry out fully non-perturbative microscopic Quantum Monte Carlo calculations of the energy of neutron matter at different densities, as well as different strengths and periodicities of the external potential. In order to remove systematic errors, we examine finite-size effects and the impact of the wave function ansatz. We also make contact with energy-density functional theories of nuclei and disentangle isovector gradient contributions from bulk properties. Finally, we calculate the static density-density linear response function of neutron matter and compare it with the response of other physical systems.

  9. Chiral condensate in neutron matter

    E-Print Network [OSTI]

    N. Kaiser; W. Weise

    2008-08-06

    A recent chiral perturbation theory calculation of the in-medium quark condensate $$ is extended to the isospin-asymmetric case of pure neutron matter. In contrast to the behavior in isospin-symmetric nuclear matter we find only small deviations from the linear density approximation. This feature originates primarily from the reduced weight factors (e.g. 1/6 for the dominant contributions) of the $2\\pi$-exchange mechanisms in pure neutron matter. Our result suggests therefore that the tendencies for chiral symmetry restoration are actually favored in systems with large neutron excess (e.g. neutron stars). We also analyze the behavior of the density-dependent quark condensate $(\\rho_n)$ in the chiral limit $m_\\pi\\to 0$.

  10. Coal dust contiguity-induced changes in the concentration of TNF- and NF- B p65 on the ocular surface

    SciTech Connect (OSTI)

    Sun, Z.Y.; Hong, J.; Liu, Z.Y.; Jin, X.D.; Gu, C.H.

    2009-07-01

    To observe the influence of coal dust on ocular surface of coal miners and rabbits with coal dust contiguity on expression TNF- and NF- Bp65 and dry eye occurrence. Expression TNF- and NF- Bp65 in ocular surface were determined. Results showed tear production, BUT and lysozyme decreased for coal miners and rabbits with coal dust contiguity. Coal dust exposure was linked to development of xerophthalmia, and induced a higher expression of NF- B p65 and TNF- perhaps as a mechanism to resist coal dust ocular surface injury.

  11. Modeling the global emission, transport and deposition of trace elements associated with mineral dust

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Y.; Mahowald, N.; Scanza, R.; Journet, E.; Desboeufs, K.; Albani, S.; Kok, J.; Zhuang, G.; Chen, Y.; Cohen, D. D.; et al

    2014-12-17

    Trace element deposition from desert dust has important impacts on ocean primary productivity. In this study, emission inventories for 8 elements, which are primarily of soil origin, Mg, P, Ca, Mn, Fe, K, Al, and Si were determined based on a global mineral dataset and a soils dataset. Datasets of elemental fractions were used to drive the desert dust model in the Community Earth System Model (CESM) in order to simulate the elemental concentrations of atmospheric dust. Spatial variability of mineral dust elemental fractions was evident on a global scale, particularly for Ca. Simulations of global variations in the Camore »/ Al ratio, which typically ranged from around 0.1 to 5.0 in soil sources, were consistent with observations, suggesting this ratio to be a good signature for dust source regions. The simulated variable fractions of chemical elements are sufficiently different that estimates of deposition should include elemental variations, especially for Ca, Al and Fe. The model results have been evaluated with observational elemental aerosol concentration data from desert regions and dust events in non-dust regions, providing insights into uncertainties in the modeling approach. The ratios between modeled and observed elemental fractions ranged from 0.7 to 1.6 except for 3.4 and 3.5 for Mg and Mn, respectivly. Using the soil data base improved the correspondence of the spatial hetereogeneity in the modeling of several elements (Ca, Al and Fe) compared to observations. Total and soluble dust associated element fluxes into different ocean basins and ice sheets regions have been estimated, based on the model results. Annual inputs of soluble Mg, P, Ca, Mn, Fe and K associated with dust using mineral dataset were 0.28 Tg, 16.89 Gg, 1.32 Tg, 22.84 Gg, 0.068 Tg, and 0.15 Tg to global oceans and ice sheets.« less

  12. Will new horizons see dust clumps in the Edgeworth-Kuiper Belt?

    SciTech Connect (OSTI)

    Vitense, Christian; Krivov, Alexander V.; Löhne, Torsten

    2014-06-01

    Debris disks are thought to be sculptured by neighboring planets. The same is true for the Edgeworth-Kuiper debris disk, yet no direct observational evidence for signatures of giant planets in the Kuiper Belt dust distribution has been found so far. Here we model the dust distribution in the outer solar system to reproduce the dust impact rates onto the dust detector on board the New Horizons spacecraft measured so far and to predict the rates during the Neptune orbit traverse. To this end, we take a realistic distribution of trans-Neptunian objects to launch a sufficient number of dust grains of different sizes and follow their orbits by including radiation pressure, Poynting-Robertson and stellar wind drag, as well as the perturbations of four giant planets. In a subsequent statistical analysis, we calculate number densities and lifetimes of the dust grains in order to simulate a collisional cascade. In contrast to the previous work, our model not only considers collisional elimination of particles but also includes production of finer debris. We find that particles captured in the 3:2 resonance with Neptune build clumps that are not removed by collisions, because the depleting effect of collisions is counteracted by production of smaller fragments. Our model successfully reproduces the dust impact rates measured by New Horizons out to ?23 AU and predicts an increase of the impact rate of about a factor of two or three around the Neptune orbit crossing. This result is robust with respect to the variation of the vaguely known number of dust-producing scattered disk objects, collisional outcomes, and the dust properties.

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

    E-Print Network [OSTI]

    Plemons, Dorothy Sue

    1981-01-01

    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...

  14. Electrical time resolved metrology of dust particles growing in low pressure cold plasmas

    SciTech Connect (OSTI)

    Wattieaux, Gaeetan [PRISME, Orleans University, 12 rue de Blois BP 6744, 45067 Orleans cedex 2 (France); Mezeghrane, Abdelaziz [LPCQ, Mouloud Mammeri University, Tizi-Ouzou (Algeria); Boufendi, Laiefa [GREMI, Orleans University, 14 rue d'Issoudun BP 6744, 45067 Orleans cedex 2 (France)

    2011-09-15

    The electrical parameters of a capacitively coupled radiofrequency (CCRF) discharge change significantly when dust arises in the discharge. This work demonstrates the ability to follow in real time the evolution of the size and of the concentration of dust particles forming in a CCRF discharge from the variation of the electron density and of the self-bias voltage of the active electrode. According to experimental findings, it appears that the variation of this self-bias voltage depends on the surface of the dust particles. This trend is confirmed by an analytical modelling considering the low frequency behaviour of the phenomenon.

  15. Observed 20th Century Desert Dust Variability: Impact on Climate and Biogeochemistry

    SciTech Connect (OSTI)

    Mahowald, Natalie; Kloster, Silvia; Engelstaedter, S.; Moore, Jefferson Keith; Mukhopadhyay, S.; McConnell, J. R.; Albani, S.; Doney, Scott C.; Bhattacharya, A.; Curran, M. A. J.; Flanner, Mark G.; Hoffman, Forrest M; Lawrence, David M.; Lindsay, Keith; Mayewski, P. A.; Neff, Jason; Rothenberg, D.; Thomas, E.; Thornton, Peter E; Zender, Charlie S.

    2010-01-01

    Desert dust perturbs climate by directly and indirectly interacting with incoming solar and outgoing long wave radiation, thereby changing precipitation and temperature, in addition to modifying ocean and land biogeochemistry. While we know that desert dust is sensitive to perturbations in climate and human land use, previous studies have been unable to determine whether humans were increasing or decreasing desert dust in the global average. Here we present observational estimates of desert dust based on paleodata proxies showing a doubling of desert dust during the 20th century over much, but not all the globe. Large uncertainties remain in estimates of desert dust variability over 20th century due to limited data. Using these observational estimates of desert dust change in combination with ocean, atmosphere and land models, we calculate the net radiative effect of these observed changes (top of atmosphere) over the 20th century to be -0.14 {+-} 0.11 W/m{sup 2} (1990-1999 vs. 1905-1914). The estimated radiative change due to dust is especially strong between the heavily loaded 1980-1989 and the less heavily loaded 1955-1964 time periods (-0.57 {+-} 0.46 W/m{sup 2}), which model simulations suggest may have reduced the rate of temperature increase between these time periods by 0.11 C. Model simulations also indicate strong regional shifts in precipitation and temperature from desert dust changes, causing 6 ppm (12 PgC) reduction in model carbon uptake by the terrestrial biosphere over the 20th century. Desert dust carries iron, an important micronutrient for ocean biogeochemistry that can modulate ocean carbon storage; here we show that dust deposition trends increase ocean productivity by an estimated 6% over the 20th century, drawing down an additional 4 ppm (8 PgC) of carbon dioxide into the oceans. Thus, perturbations to desert dust over the 20th century inferred from observations are potentially important for climate and biogeochemistry, and our understanding of these changes and their impacts should continue to be refined.

  16. African Dust Influence on Atlantic Hurricane Activity and the Peculiar Behaviour of Category 5 Hurricanes

    E-Print Network [OSTI]

    Herrera, Victor M Velasco; H., Graciela Velasco; Gonzalez, Laura Luna

    2010-01-01

    We study the specific influence of African dust on each one of the categories of Atlantic hurricanes. By applying wavelet analysis, we find a strong decadal modulation of African dust on Category 5 hurricanes and an annual modulation on all other categories of hurricanes. We identify the formation of Category 5 hurricanes occurring mainly around the decadal minimum variation of African dust and in deep water areas of the Atlantic Ocean, where hurricane eyes have the lowest pressure. According to our results, future tropical cyclones will not evolve to Category 5 until the next decadal minimum that is, by the year 2015 +/- 2.

  17. El Roque de Los Muchachos Site Characteristics. III. Analysis of Atmospheric Dust and Aerosol Extinction

    E-Print Network [OSTI]

    G. Lombardi; V. Zitelli; S. Ortolani; M. Pedani; A. Ghedina

    2008-03-26

    Canary Islands are normally interested by dominant North-East winds that, in some meteorological conditions, can transport sand at high altitude from the Sahara desert. The dust may affect the efficiency of the telescopes and decreases the transparency of the sky. In order to maximize the scientific return of the telescopes located at the ORM, we present an analysis of the atmospheric dust content and its effects on astronomical observations. B, V and I dust aerosol astronomical extinction are derived. Using a 5 years series database of data taken from the four channel TNG dust monitor, we compute a mean hourly and daily values of the dust content. We have detected particles having size 0.3, 0.5, 1.0 and 5.0 um. Using a power law we have derived the content of 10.0 um particles. We found a typical local dust concentration ranging from 3x10^6 particles per cubic meter at 0.3 um, to 10^3 at 5.0 um and 10 at 10.0 um, increasing up to 3 order of magnitudes during the dust storms, with a relative higher increase of 1.0, 5.0 and 10.0 um particles. The number of local dust storm events is the same in winter- and summertime, but, the average background and storm-related increases in the dust concentration in summer are significantly higher than in winter. In a uniform approximation, during the dust storms, an average height of the dust layer of 2.5 km above the telescope is inferred. During the sand storms La Palma Island is affected by an almost uniform layer extending up to 5 km above the sea level, down, at least the height of the telescope. The visible extinction is dominated by particles at 1.0, 5.0 and 10.0 um. In agreement with the results from Carlsberg Automatic Meridian Circle (CAMC) we find a typical extinction during dust storms of about 0.2 mag/airmass.

  18. Modelling of mineral dust for interglacial and glacial climate conditions with a focus on Antarctica

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sudarchikova, Natalia; Mikolajewicz, Uwe; Timmreck, C.; O'Donnell, D.; Schurgers, G.; Sein, Dmitry; Zhang, Kai

    2015-05-19

    The mineral dust cycle responds to climate variations and plays an important role in the climate system by affecting the radiative balance of the atmosphere and modifying biogeochemistry. Polar ice cores provide unique information about deposition of aeolian dust particles transported over long distances. These cores are a palaeoclimate proxy archive of climate variability thousands of years ago. The current study is a first attempt to simulate past interglacial dust cycles with a global aerosol–climate model ECHAM5-HAM. The results are used to explain the dust deposition changes in Antarctica in terms of quantitative contribution of different processes, such as emission,more »atmospheric transport and precipitation, which will help to interpret palaeodata from Antarctic ice cores. The investigated periods include four interglacial time slices: the pre-industrial control (CTRL), mid-Holocene (6000 yr BP; hereafter referred to as \\"6 kyr\\"), last glacial inception (115 000 yr BP; hereafter \\"115 kyr\\") and Eemian (126 000 yr BP; hereafter \\"126 kyr\\"). One glacial time interval, the Last Glacial Maximum (LGM) (21 000 yr BP; hereafter \\"21 kyr\\"), was simulated as well to be a reference test for the model. Results suggest an increase in mineral dust deposition globally, and in Antarctica, in the past interglacial periods relative to the pre-industrial CTRL simulation. Approximately two-thirds of the increase in the mid-Holocene and Eemian is attributed to enhanced Southern Hemisphere dust emissions. Slightly strengthened transport efficiency causes the remaining one-third of the increase in dust deposition. The moderate change in dust deposition in Antarctica in the last glacial inception period is caused by the slightly stronger poleward atmospheric transport efficiency compared to the pre-industrial. Maximum dust deposition in Antarctica was simulated for the glacial period. LGM dust deposition in Antarctica is substantially increased due to 2.6 times higher Southern Hemisphere dust emissions, 2 times stronger atmospheric transport towards Antarctica, and 30% weaker precipitation over the Southern Ocean. The model is able to reproduce the order of magnitude of dust deposition globally and in Antarctica for the pre-industrial and LGM climates.« less

  19. Dust Dynamics in Protoplanetary Disk Winds Driven by Magneto-Rotational Turbulence: A Mechanism for Floating Dust Grains with Characteristic Size

    E-Print Network [OSTI]

    Miyake, Tomoya; Inutsuka, Shu-ichiro

    2015-01-01

    We investigate the dynamics of dust grains with various sizes in protoplanetary disk winds driven by magnetorotational turbulence, by simulating the time evolution of the dust grain distribution in the vertical direction. Small dust grains, which are well coupled to the gas, are dragged upward with the upflowing gas, while large grains remain near the midplane of a disk. Intermediate--size grains float at several scale heights from the midplane in time-averated force balance between the downward gravity and the upward gas drag. For the minimum mass solar nebula at 1 AU, dust grains with size of 20 -- 40 $\\mu m$ float at 5-10 scale heights from the midplane. Considering the dependence on the distance from the central star, smaller-size grains remain only in an outer region of the disk, while larger-size grains are distributed in a broader region. This implies that the dust depletion is expected to take place in small-to-large and inside-out manners. We also discuss the implication of our result to the observat...

  20. Pump Systems Matter Mission and Vision | Department of Energy

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

    ionofPumpSystemsMatter.pdf More Documents & Publications Overview of Pump Systems Matter Hydraulic Institute Mission and Vision Course Overview Pump Systems Matter Optimization...

  1. Why Geology Matters: Decoding the Past, Anticipating the Future

    E-Print Network [OSTI]

    Anderson, Byron P.

    2011-01-01

    Review: Why Geology Matters: Decoding the Past, AnticipatingUSA Macdougall, Doug. Why Geology Matters: Decoding theE-book available. Why Geology Matters pursues two goals: to

  2. Apparatus for particulate matter analysis

    DOE Patents [OSTI]

    Gundel, Lara A.; Apte, Michael G.; Hansen, Anthony D.; Black, Douglas R.

    2007-01-30

    The apparatus described herein is a miniaturized system for particle exposure assessment (MSPEA) for the quantitative measurement and qualitative identification of particulate content in gases. The present invention utilizes a quartz crystal microbalance (QCM) or other mass-sensitive temperature compensated acoustic wave resonator for mass measurement. Detectors and probes and light sources are used in combination for the qualitative determination of particulate matter.

  3. Laser Cooling of Matter INTRODUCTION

    E-Print Network [OSTI]

    Kaiser, Robin

    Laser Cooling of Matter INTRODUCTION Laser cooling of neutral atoms in the past decades has been a breakthrough in the understanding of their dy- namics and led to the seminal proposals of laser cooling-Doppler and subrecoil cooling, as well as new technologies, such as semiconductor diode lasers. Most of those

  4. States of Matter Deepak Dhar

    E-Print Network [OSTI]

    Udgaonkar, Jayant B.

    - logical classification of different animal species) or some mixture of these (e.g. books in a library answer in this case is that states of matter is a classification scheme, like filing cabinets classification schemes could be alphabetical (e.g. in a dictionary), or based on some common properties ( zoo

  5. Wino dark matter under siege

    SciTech Connect (OSTI)

    Cohen, Timothy; Lisanti, Mariangela; Pierce, Aaron; Slatyer, Tracy R. E-mail: mlisanti@princeton.edu E-mail: tslatyer@mit.edu

    2013-10-01

    A fermion triplet of SU(2){sub L} — a wino — is a well-motivated dark matter candidate. This work shows that present-day wino annihilations are constrained by indirect detection experiments, with the strongest limits coming from H.E.S.S. and Fermi. The bounds on wino dark matter are presented as a function of mass for two scenarios: thermal (winos constitute a subdominant component of the dark matter for masses less than 3.1 TeV) and non-thermal (winos comprise all the dark matter). Assuming the NFW halo model, the H.E.S.S. search for gamma-ray lines excludes the 3.1 TeV thermal wino; the combined H.E.S.S. and Fermi results completely exclude the non-thermal scenario. Uncertainties in the exclusions are explored. Indirect detection may provide the only probe for models of anomaly plus gravity mediation where the wino is the lightest superpartner and scalars reside at the 100 TeV scale.

  6. Solar Neutrino Matter Effects Redux

    E-Print Network [OSTI]

    A. B. Balantekin; A. Malkus

    2011-12-19

    Following recent low-threshold analysis of the Sudbury Neutrino Observatory and asymmetry measurements of the BOREXINO Collaboration of the solar neutrino flux, we revisit the analysis of the matter effects in the Sun. We show that solar neutrino data constrains the mixing angle $\\theta_{13}$ poorly and that subdominant Standard Model effects can mimic the effects of the physics beyond the Standard Model.

  7. Neutrino Mass and Dark Matter

    E-Print Network [OSTI]

    David O. Caldwell

    1998-12-01

    Despite direct observations favoring a low mass density, a critical density universe with a neutrino component of dark matter provides the best existing model to explain the observed structure of the universe over more than three orders of magnitude in distance scale. In principle this hot dark matter could consist of one, two, or three species of active neutrinos. If all present indications for neutrino mass are correct, however, only the two-species (muon neutrino and tau neutrino) possibility works. This requires the existence of at least one light sterile neutrino to explain the solar electron neutrino deficit via nu(e)->nu(s), leaving nu(mu)->nu(tau) as the explanation for the anomalous nu(mu)/nu(e) ratio produced by atmospheric neutrinos, and having the LSND experiment demonstrating via anti-nu(mu)-> anti-nu(e) the mass difference between the light nu(e)-nu(s) pair and the heavier nu(mu)-nu(tau) pair required for dark matter. Other experiments do not conflict with the LSND results when all the experiments are analyzed in the same way, and when analyzed conservatively the LSND data is quite compatible with the mass difference needed for dark matter. Further support for this mass pattern is provided by the need for a sterile neutrino to rescue heavy-element nucleosynthesis in supernovae, and it could even aid the concordance in light element abundances from the early universe.

  8. The matter bounce scenario in loop quantum cosmology

    SciTech Connect (OSTI)

    Wilson-Ewing, Edward, E-mail: wilson-ewing@cpt.univ-mrs.fr [Aix-Marseille Université, CNRS UMR 7332, CPT, 13288 Marseille (France)

    2013-03-01

    In the matter bounce scenario, a dust-dominated contracting space-time generates scale-invariant perturbations that, assuming a nonsingular bouncing cosmology, propagate to the expanding branch and set appropriate initial conditions for the radiation-dominated era. Since this scenario depends on the presence of a bounce, it seems appropriate to consider it in the context of loop quantum cosmology where a bouncing universe naturally arises. For a pressureless collapsing universe in loop quantum cosmology, the predicted power spectrum of the scalar perturbations after the bounce is scale-invariant and the tensor to scalar ratio is negligibly small. A slight red tilt can be given to the scale-invariance of the scalar perturbations by a scalar field whose equation of state is P = ???, where ? is a small positive number. Then, the power spectrum for tensor perturbations is also almost scale-invariant with the same red tilt as the scalar perturbations, and the tensor to scalar ratio is expected to be r ? 9 × 10{sup ?4}. Finally, for the predicted amplitude of the scalar perturbations to agree with observations, the critical density in loop quantum cosmology must be of the order ?{sub c} ? 10{sup ?9}?{sub Pl}.

  9. Three-dimensional dust-ion-acoustic rogue waves in a magnetized dusty pair-ion plasma with nonthermal nonextensive electrons and opposite polarity dust grains

    SciTech Connect (OSTI)

    Guo, Shimin Mei, Liquan

    2014-08-15

    Dust-ion-acoustic (DIA) rogue waves are investigated in a three-dimensional magnetized plasma containing nonthermal electrons featuring Tsallis distribution, both positive and negative ions, and immobile dust grains having both positive and negative charges. Via the reductive perturbation method, a (3?+?1)-dimensional nonlinear Schrödinger (NLS) equation is derived to govern the dynamics of the DIA wave packets. The modulation instability of DIA waves described by the (3?+?1)-dimensional NLS equation is investigated. By means of the similarity transformation and symbolic computation, both the first- and second-order rogue wave solutions of the (3?+?1)-dimensional NLS equation are constructed in terms of rational functions. Moreover, the dynamics properties and the effects of plasma parameters on the nonlinear structures of rogue waves are discussed in detail. The results could be useful for understanding the physical mechanism of rogue waves in laboratory experiments where pair-ion plasmas with electrons and dust grains can be found.

  10. Cold quark matter in compact stars

    SciTech Connect (OSTI)

    Franzon, B.; Fogaca, D. A.; Navarra, F. S.; Horvath, J. E.

    2013-03-25

    We used an equation of state for the cold quark matter to the study of properties of quark stars. We also discuss the absolute stability of quark matter and compute the mass-radius relation for self-bound stars.

  11. Microfiltration of colloids and natural organic matter 

    E-Print Network [OSTI]

    Schäfer, Andrea; Schwicke, U.; Fischer, M. M.; Fane, Anthony G.; Waite, T. D.

    2000-01-01

    Surface waters contain colloids and natural organic matter, largely composed of humic substances. In this work the effect of natural organic matter (NOM) and humic substances (IHSS stream humic and fulvic acid reference ...

  12. Strongly Interacting Matter at High Energy Density

    E-Print Network [OSTI]

    Larry McLerran

    2008-12-08

    This lecture concerns the properties of strongly interacting matter (which is described by Quantum Chromodynamics) at very high energy density. I review the properties of matter at high temperature, discussing the deconfinement phase transition . At high baryon density and low temperature, large $N_c$ arguments are developed which suggest that high baryonic density matter is a third form of matter, Quarkyonic Matter, that is distinct from confined hadronic matter and deconfined matter. I finally discuss the Color Glass Condensate which controls the high energy limit of QCD, and forms the low x part of a hadron wavefunction. The Glasma is introduced as matter formed by the Color Glass Condensate which eventually thermalizes into a Quark Gluon Plasma.

  13. IS DUST FORMING ON THE RED GIANT BRANCH IN 47 Tuc?

    SciTech Connect (OSTI)

    Boyer, Martha L.; Gordon, Karl D.; Meixner, Margaret; Sewilo, Marta; Shiao, Bernie [STScI, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Van Loon, Jacco Th. [Astrophysics Group, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG (United Kingdom); McDonald, Iain [Jodrell Bank Centre for Astrophysics, Alan Turing Building, University of Manchester, M13 9PL (United Kingdom); Babler, Brian; Bracker, Steve; Meade, Marilyn [Department of Astronomy, University of Wisconsin, Madison, 475 North Charter Street, Madison, WI 53706-1582 (United States); Block, Miwa; Engelbracht, Charles; Misselt, Karl [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Hora, Joe [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 65, Cambridge, MA 02138-1516 (United States); Indebetouw, Remy [Department of Astronomy, University of Virginia, P.O. Box 3818, Charlottesville, VA 22903-0818 (United States); Whitney, Barbara [Space Science Institute, 4750 Walnut Street, Suite 205, Boulder, CO 80301 (United States)], E-mail: mboyer@stsci.edu

    2010-03-10

    Using Spitzer Infrared Array Camera (IRAC) observations from the SAGE-SMC Legacy program and archived Spitzer IRAC data, we investigate dust production in 47 Tuc, a nearby massive Galactic globular cluster. A previous study detected infrared excess, indicative of circumstellar dust, in a large population of stars in 47 Tuc, spanning the entire red giant branch (RGB). We show that those results suffered from effects caused by stellar blending and imaging artifacts and that it is likely that no stars below {approx}1 mag from the tip of the RGB are producing dust. The only stars that appear to harbor dust are variable stars, which are also the coolest and most luminous stars in the cluster.

  14. COSMIC DUST--NEAR AND FAR ASP Conference Series, Vol. 414, 2009

    E-Print Network [OSTI]

    Draine, Bruce T.

    COSMIC DUST--NEAR AND FAR ASP Conference Series, Vol. 414, 2009 Th. Henning, E. Gr¨un, and Jµm-1 , this is based on the parameterization of extinction by Fitzpatrick (1999), with addition of 77

  15. Effects of radiofrequency on dust particle dynamics in a plasma reactor

    SciTech Connect (OSTI)

    Horn, C.; Shotorban, B. [Department of Mechanical and Aerospace Engineering, University of Alabama in Huntsville, Huntsville, Alabama 35899 (United States); Davoudabadi, M. [ANSYS, Inc., Evanston, Illinois 60201 (United States)

    2011-12-01

    A numerical solution is obtained for the electron and ion number densities, and electric field of an rf argon plasma in a low pressure reactor utilizing a one-dimensional model. These variables are used to solve the equations describing the dynamical behavior of a dust particle under the influence of the electrical, gravity, and ion and neutral drag forces. The effects of the rf oscillations of the plasma on the dust particle are investigated through comparisons made between two sets of results. The first set is generated by a model in which the rf-period-averaged plasma variables are used in the dust particle equations while the second set is generated using the instantaneous plasma variables, without rf-period averaging. These two sets of results including the positions and charges of, and the various forces acting on the dust particles with different sizes and densities, are compared and significant differences are found.

  16. Light Scattering by Ice Crystals and Mineral Dust Aerosols in the Atmosphere 

    E-Print Network [OSTI]

    Bi, Lei

    2012-07-16

    Modeling the single-scattering properties of nonspherical particles in the atmo¬sphere (in particular, ice crystals and dust aerosols) has important applications to climate and remote sensing studies. The ?rst part of the dissertation (Chapters II...

  17. A laboratory study comparing the effectiveness of three dust palliatives on unpaved roads 

    E-Print Network [OSTI]

    Ehsan, Mehbuba

    1999-01-01

    during this research and used for measuring material loss due to wind erosion. A modified South African durability test was used to simulate erosion due to traffic. Results obtained indicate that the use of dust palliatives can significantly reduce...

  18. Neutral hydrogen structures trace dust polarization angle: Implications for the interstellar medium and CMB foregrounds

    E-Print Network [OSTI]

    Clark, S E; Peek, J E G; Putman, M E; Babler, B L

    2015-01-01

    Using high-resolution data from the Galactic Arecibo L-Band Feed Array HI (GALFA-HI) survey, we show that linear structure in Galactic neutral hydrogen (HI) correlates with the magnetic field orientation implied by Planck 353 GHz polarized dust emission. The structure of the neutral interstellar medium is more tightly coupled to the magnetic field than previously known. At high Galactic latitudes, where the Planck data are noise-dominated, the HI data provide an independent constraint on the Galactic magnetic field orientation, and hence the local dust polarization angle. We detect strong cross-correlations between template maps constructed from estimates of dust intensity combined with either HI-derived angles, starlight polarization angles, or Planck 353 GHz angles. The HI data thus provide a new tool in the search for inflationary gravitational wave B-mode polarization in the cosmic microwave background, which is currently limited by dust foreground contamination.

  19. Observed 20th century desert dust variability: impact on climate and biogeochemistry

    E-Print Network [OSTI]

    2010-01-01

    Understanding the 30-year Barbados desert dust record, J.tration data observed at Barbados (Prospero and Lamb, 2003)on the shorter in situ Barbados concentration data (1968 to

  20. MRF Technical Note # 49 Can desert dust explain the anomalous greenhouse

    E-Print Network [OSTI]

    Allan, Richard P.

    MRF Technical Note # 49 Can desert dust explain the anomalous greenhouse effect observed over greenhouse effect observed over the Sahara during July 2003 revealed by GERB/UM intercomparisons? Jim M

  1. Geek-Up[6.24.11]: Dust-sized 'Dragonfly' Device and Tiny Microvalves

    Broader source: Energy.gov [DOE]

    A dust-size "dragonfly-inspired" device -- which won a Sandia Lab design contest -- may ultimately enable the creation of tiny microvalves for experiments in biological research laboratories and medical facilities.

  2. Tanpopo cosmic dust collector: Silica aerogel production and bacterial DNA contamination analysis

    E-Print Network [OSTI]

    Tabata, Makoto; Yokobori, Shin-ichi; Kawai, Hideyuki; Takahashi, Jun-ichi; Yano, Hajime; Yamagishi, Akihiko

    2011-01-01

    Hydrophobic silica aerogels with ultra-low densities have been designed and developed as cosmic dust capture media for the Tanpopo mission which is proposed to be carried out on the International Space Station. Glass particles as a simulated cosmic dust with 30 \\mu m in diameter and 2.4 g/cm^3 in density were successfully captured by the novel aerogel at a velocity of 6 km/s. Background levels of contaminated DNA in the ultra-low density aerogel were lower than the detection limit of a polymerase chain reaction assay. These results show that the manufactured aerogel has good performance as a cosmic dust collector and sufficient quality in respect of DNA contamination. The aerogel is feasible for the biological analyses of captured cosmic dust particles in the astrobiological studies.

  3. Dark Energy and Dark Matter From Hidden Symmetry of Gravity Model with a Non-Riemannian Volume Form

    E-Print Network [OSTI]

    Guendelman, Eduardo; Pacheva, Svetlana

    2015-01-01

    We show that dark energy and dark matter can be described simultaneously by ordinary Einstein gravity interacting with a single scalar field provided the scalar field Lagrangian couples in a symmetric fashion to two different spacetime volume-forms (covariant integration measure densities) on the spacetime manifold - one standard Riemannian given by the square-root of the determinant of the pertinent Riemannian metric and another non-Riemannian volume-form independent of the Riemannian metric, defined in terms of an auxiliary antisymmetric tensor gauge field of maximal rank. Integration of the equations of motion of the latter auxiliary gauge field produce an a priori arbitrary integration constant that plays the role of a dynamically generated cosmological constant or dark energy. Moreover, the above modified scalar field action turns out to possess a hidden Noether symmetry whose associated conserved current describes a pressureless "dust" fluid which we can identify with the dark matter completely decouple...

  4. Indirect searches for neutralino dark matter

    E-Print Network [OSTI]

    Joakim Edsjo

    2002-11-15

    There is mounting evidence for dark matter in the Universe and one of the favourite dark matter candidates is the neutralino, which naturally appears as the lightest supersymmetric particle (LSP) in many supersymmetric extensions of the standard model. The neutralino has the desired properties to be a good dark matter candidate and we will here review the different indirect searches for neutralino dark matter and discuss the implications on these from recent direct searches.

  5. Operations & Maintenance Best Practices Guide: Front Matter

    Broader source: Energy.gov [DOE]

    Guide describes the front matter of the Operations and Maintenance Best Practices: a Guide to Achieving Operational Efficiency.

  6. Metabolite Signatures in Hydrophilic Extracts of Mouse Lungs Exposed to Cigarette Smoke Revealed By 1H NMR Metabolomics Investigation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hu, Jian Z.; Wang, Xuan; Feng, Ju; Webb-Robertson, Bobbie-Jo M.; Waters, Katrina M.; Tilton, Susan C.; Pounds, Joel G.; Corley, Richard A.; Liu, Maili; Hu, Mary Y.

    2015-05-12

    Herein, 1H-NMR metabolomics are carried out to evaluate the changes of metabolites in lungs of mice exposed to cigarette smoke. It is found that the concentrations of adenosine derivatives (i.e. ATP, ADP and AMP), inosine and uridine are significantly fluctuated in the lungs of mice exposed to cigarette smoke compared with those of controls regardless the mouse is obese or regular weight. The decreased ATP, ADP, AMP and elevated inosine predict that the deaminases in charge of adenosine derivatives to inosine derivatives conversion are altered in lungs of mice exposed to cigarette smoke. Transcriptional analysis reveals that the concentrations ofmore »adenosine monophosphate deaminase and adenosine deaminase are different in the lungs of mice exposed to cigarette smoke, confirming the prediction from metabolomics studies. We also found, for the first time, that the ratio of glycerophosphocholine (GPC) to phosphocholine (PC) is significantly increased in the lungs of obese mice compared with regular weight mice. The ratio of GPC/PC is further elevated in the lungs of obese group by cigarette smoke exposure. Since GPC/PC ratio is a known biomarker for cancer, these results may suggest that obese group is more susceptible to lung cancer when exposed to cigarette smoke.« less

  7. Tobacco Smoking During Radiation Therapy for Head-and-Neck Cancer Is Associated With Unfavorable Outcome

    SciTech Connect (OSTI)

    Chen, Allen M.; Chen, Leon M.; Vaughan, Andrew; Sreeraman, Radhika; Farwell, D. Gregory; Luu, Quang; Lau, Derick H.; Stuart, Kerri; Purdy, James A.; Vijayakumar, Srinivasan

    2011-02-01

    Purpose: To evaluate the effect of continued cigarette smoking among patients undergoing radiation therapy for head-and-neck cancer by comparing the clinical outcomes among active smokers and quitters. Methods and Materials: A review of medical records identified 101 patients with newly diagnosed squamous cell carcinoma of the head and neck who continued to smoke during radiation therapy. Each active smoker was matched to a control patient who had quit smoking before initiation of radiation therapy. Matching was based on tobacco history (pack-years), primary site, age, sex, Karnofsky Performance Status, disease stage, radiation dose, chemotherapy use, year of treatment, and whether surgical resection was performed. Outcomes were compared by use of Kaplan-Meier analysis. Normal tissue effects were graded according to the Radiation Therapy Oncology Group/European Organization for the Treatment of Cancer toxicity criteria. Results: With a median follow-up of 49 months, active smokers had significantly inferior 5-year overall survival (23% vs. 55%), locoregional control (58% vs. 69%), and disease-free survival (42% vs. 65%) compared with the former smokers who had quit before radiation therapy (p < 0.05 for all). These differences remained statistically significant when patients treated by postoperative or definitive radiation therapy were analyzed separately. The incidence of Grade 3 or greater late complications was also significantly increased among active smokers compared with former smokers (49% vs. 31%, p = 0.01). Conclusions: Tobacco smoking during radiation therapy for head-and-neck cancer is associated with unfavorable outcomes. Further studies analyzing the biologic and molecular reasons underlying these differences are planned.

  8. Guide to Quit Smoking *Based on 52 weeks in a year.

    E-Print Network [OSTI]

    starts taking the pills a week or two before their quit date. How to Quit Set a Quit Date This gives you plan to use medicine to help you quit, make sure you know how to use them. Stock up on sugar-free gum--880000--QQUUIITT--NNOOWW Take Control Call. It's free. It works. It'll help you quit smoking. Breathe better Enjoy

  9. Gossypol content of industrial cotton dust: evaluation and application of the Gossypol - Aniline complex method 

    E-Print Network [OSTI]

    Gruenwald, Guillermo Jose Samuel

    1974-01-01

    , The lay terms used in the early days of the recognition of this disease include: "mill fever ", "weavers cough". "weaver. s a. , thma", 'cotton dust disease", "brown ung", "Noonday morning fever", etc. 17 Byssinosis symptoms may be noted after... cough incessantly and by degrees brings on asthmatic troubles. ? The American researcher, Winslow, aghast , 5 mill conditions t n the ear ly '1900's noted the hazards o "the carding room" with the clouds of f ine chokihg dust. " 5 6 Later...

  10. Filamentation instability of current-driven dust ion-acoustic waves in a collisional dusty plasma

    SciTech Connect (OSTI)

    Niknam, A. R. [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran 19839-63113 (Iran, Islamic Republic of); Haghtalab, T.; Khorashadizadeh, S. M. [Physics Department, Birjand University, Birjand 97179-63384 (Iran, Islamic Republic of)

    2011-11-15

    A theoretical investigation has been made of the dust ion-acoustic filamentation instability in an unmagnetized current-driven dusty plasma by using the Lorentz transformation formulas. The effect of collision between the charged particles with neutrals and their thermal motion on this instability is considered. Developing the filamentation instability of the current-driven dust ion-acoustic wave allows us to determine the period and the establishment time of the filamentation structure and threshold for instability development.

  11. Molecular Hydrogen Emission from Protoplanetary Disks II. Effects of X-ray Irradiation and Dust Evolution

    E-Print Network [OSTI]

    H. Nomura; Y. Aikawa; M. Tsujimoto; Y. Nakagawa; T. J. Millar

    2007-02-01

    Detailed models for the density and temperature profiles of gas and dust in protoplanetary disks are constructed by taking into account X-ray and ultraviolet (UV) irradiation from a central T Tauri star, as well as dust size growth and settling toward the disk midplane. The spatial and size distributions of dust grains in the disks are numerically computed by solving the coagulation equation for settling dust particles. The level populations and line emission of molecular hydrogen are calculated using the derived physical structure of the disks. X-ray irradiation is the dominant heating source of the gas in the inner disk region and in the surface layer, while the far UV heating dominates otherwise. If the central star has strong X-ray and weak UV radiation, the H2 level populations are controlled by X-ray pumping, and the X-ray induced transition lines could be observable. If the UV irradiation is strong, the level populations are controlled by thermal collisions or UV pumping, depending on the properties of the dust grains in the disks. As the dust particles evolve in the disks, the gas temperature at the disk surface drops because the grain photoelectric heating becomes less efficient, while the UV radiation fields become stronger due to the decrease of grain opacity. This makes the H2 level populations change from local thermodynamic equilibrium (LTE) to non-LTE distributions, which results in changes to the line ratios of H2 emission. Our results suggest that dust evolution in protoplanetary disks could be observable through the H2 line ratios. The emission lines are strong from disks irradiated by strong UV and X-rays and possessing small dust grains; such disks will be good targets in which to observe H2 emission.

  12. Nuclear matter to strange matter transition in holographic QCD

    E-Print Network [OSTI]

    Youngman Kim; Yunseok Seo; Sang-Jin Sin

    2009-11-19

    We construct a simple holographic QCD model to study nuclear matter to strange matter transition. The interaction of dense medium and hadrons is taken care of by imposing the force balancing condition for stable D4/D6/D6 configuration. By considering the intermediate and light flavor branes interacting with baryon vertex homogeneously distributed along R^3 space and requesting the energy minimization, we find that there is a well defined transition density as a function of current quark mass. We also find that as density goes up very high, intermediate (or heavy) and light quarks populate equally as expected from the Pauli principle. In this sense, the effect of the Pauli principle is realized as dynamics of D-branes.

  13. Dark Matter Searches with Representing the

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    · Supernova Remnants · Unidentified Gamma-ray Sources · Gamma-Ray Bursts · Solar Physics · Dark Matter #12;SCIPP talk Larry Wai / SLAC 4 Talk overview 1. What is GLAST? 2. How does dark matter shine in gamma rays? 3. Where should we look for dark matter with GLAST? #12;SCIPP talk Larry Wai / SLAC 5 GLAST

  14. Personal Finance Make Your Money Matter

    E-Print Network [OSTI]

    Stevenson, Mark

    Personal Finance Make Your Money Matter Name: Registration number: Department: Year of study of your portfolio. #12;Personal Finance Make Your Money Matter2 Contents Timetable Page 3 Introduction 16 #12;Personal Finance Make Your Money Matter3 Timetable Friday 6.00 pm Introduction

  15. The smoke-fireplume model : tool for eventual application to prescribed burns and wildland fires.

    SciTech Connect (OSTI)

    Brown, D. F.; Dunn, W. E.; Lazaro, M. A.; Policastro, A. J.

    1999-08-17

    Land managers are increasingly implementing strategies that employ the use of fire in prescribed burns to sustain ecosystems and plan to sustain the rate of increase in its use over the next five years. In planning and executing expanded use of fire in wildland treatment it is important to estimate the human health and safety consequences, property damage, and the extent of visibility degradation from the resulting conflagration-pyrolysis gases, soot and smoke generated during flaming, smoldering and/or glowing fires. Traditional approaches have often employed the analysis of weather observations and forecasts to determine whether a prescribed burn will affect populations, property, or protected Class I areas. However, the complexity of the problem lends itself to advanced PC-based models that are simple to use for both calculating the emissions from the burning of wildland fuels and the downwind dispersion of smoke and other products of pyrolysis, distillation, and/or fuels combustion. These models will need to address the effects of residual smoldering combustion, including plume dynamics and optical effects. In this paper, we discuss a suite of tools that can be applied for analyzing dispersion. These tools include the dispersion models FIREPLUME and SMOKE, together with the meteorological preprocessor SEBMET.

  16. The effect of smoking cessation pharmacotherapies on pancreatic beta cell function

    SciTech Connect (OSTI)

    Woynillowicz, Amanda K. [Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON, Canada L8N 3Z5 (Canada)] [Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON, Canada L8N 3Z5 (Canada); Raha, Sandeep [Department of Pediatrics, McMaster University, Hamilton, ON, Canada L8N 3Z5 (Canada)] [Department of Pediatrics, McMaster University, Hamilton, ON, Canada L8N 3Z5 (Canada); Nicholson, Catherine J. [Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON, Canada L8N 3Z5 (Canada)] [Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON, Canada L8N 3Z5 (Canada); Holloway, Alison C., E-mail: hollow@mcmaster.ca [Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON, Canada L8N 3Z5 (Canada)

    2012-11-15

    The goal of our study was to evaluate whether drugs currently used for smoking cessation (i.e., nicotine replacement therapy, varenicline [a partial agonist at nicotinic acetylcholine receptors (nAChR)] and bupropion [which acts in part as a nAChR antagonist]) can affect beta cell function and determine the mechanism(s) of this effect. INS-1E cells, a rat beta cell line, were treated with nicotine, varenicline and bupropion to determine their effects on beta cell function, mitochondrial electron transport chain enzyme activity and cellular/oxidative stress. Treatment of INS-1E cells with equimolar concentrations (1 ?M) of three test compounds resulted in an ablation of normal glucose-stimulated insulin secretion by the cells. This disruption of normal beta cell function was associated with mitochondrial dysfunction since all three compounds tested significantly decreased the activity of mitochondrial electron transport chain enzyme activity. These results raise the possibility that the currently available smoking cessation pharmacotherapies may also have adverse effects on beta cell function and thus glycemic control in vivo. Therefore whether or not the use of nicotine replacement therapy, varenicline and bupropion can cause endocrine changes which are consistent with impaired pancreatic function warrants further investigation. -- Highlights: ? Smoking cessation drugs have the potential to disrupt beta cell function in vitro. ? The effects of nicotine, varenicline and bupropion are similar. ? The impaired beta cell function is mediated by mitochondrial dysfunction. ? If similar effects are seen in vivo, these drugs may increase the risk of diabetes.

  17. NGC 7538 IRS. 1. Interaction of a polarized dust spiral and a molecular outflow

    SciTech Connect (OSTI)

    Wright, M. C. H.; Hull, Charles L. H. [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); Pillai, Thushara [Max Planck Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany); Zhao, Jun-Hui [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Sandell, Göran, E-mail: jzhao@cfa.harvard.edu [SOFIA-USRA, NASA Ames Research Center, MS 232-12, Building N232, Room 146, PO Box 1, Moffett Field, CA 94035-0001 (United States)

    2014-12-01

    We present dust polarization and CO molecular line images of NGC 7538 IRS 1. We combined data from the Submillimeter Array, the Combined Array for Research in Millimeter-wave Astronomy, and the James Clerk Maxwell Telescope to make images with ?2.''5 resolution at 230 and 345 GHz. The images show a remarkable spiral pattern in both the dust polarization and molecular outflow. These data dramatically illustrate the interplay between a high infall rate onto IRS 1 and a powerful outflow disrupting the dense, clumpy medium surrounding the star. The images of the dust polarization and the CO outflow presented here provide observational evidence for the exchange of energy and angular momentum between the infall and the outflow. The spiral dust pattern, which rotates through over 180° from IRS 1, may be a clumpy filament wound up by conservation of angular momentum in the infalling material. The redshifted CO emission ridge traces the dust spiral closely through the MM dust cores, several of which may contain protostars. We propose that the CO maps the boundary layer where the outflow is ablating gas from the dense gas in the spiral.

  18. On the dust environment of Main-Belt Comet 313P/Gibbs

    E-Print Network [OSTI]

    Pozuelos, F J; Licandro, J; Moreno, F

    2015-01-01

    We present observations carried out using the 10.4 m Gran Telescopio Canarias and an interpretative model of the dust environment of activated asteroid 313P/Gibbs. We discuss three different models relating to different values of the dust parameters, i.e, dust loss rate, maximum and minimum sizes of particles, power index of the size distribution, and emission pattern. The best model corresponds with an isotropic emission of particles which started on August 1st. The size of grains were in the range of $0.1-2000$ $\\mu$m, with velocities for 100 $\\mu$m particles between $0.4-1.9$ m$~$s$^{-1}$, with a dust production rate in the range of $0.2-0.8$ kg$~$s$^{-1}$. The dust tails' brightness and morphology are best interpreted in terms of a model of sustained and low dust emission driven by water-ice sublimation, spanning since 2014 August 1st, and triggered by a short impulsive event. This event produced an emission of small particles of about 0.1 $\\mu$m with velocities of $\\sim$4 m$~$s$^{-1}$. From our model we ...

  19. Proper motions of new dust in the colliding-wind binary WR 140

    E-Print Network [OSTI]

    Monnier, J D; Danchi, W C

    2002-01-01

    The eccentric WR+O binary system WR 140 produces dust for a few months at intervals of 7.94 yrs coincident with periastron passage. We present the first resolved images of this dust shell, at binary phases ~0.039 and ~0.055, using aperture masking techniques on the Keck-I telescope to achieve diffraction-limited resolution. Proper motions of approximately 1.1 milliarcsecond per day were detected, implying a distance ~1.5 kpc from the known wind speed. The dust plume observed is not as simple as the ``pinwheel'' nebulae seen around other WR colliding wind binaries, indicating the orbital plane is highly inclined to our line-of-sight and/or the dust formation is very clumpy. Follow-up imaging in the mid-infrared and with adaptive optics is urgently required to track the dust motion further, necessary for unambiguously determining the orbital geometry which we only partially constrain here. With full knowledge of the orbital elements, these infrared images can be used to reconstruct the dust distribution along t...

  20. Proper motions of new dust in the colliding-wind binary WR 140

    E-Print Network [OSTI]

    J. D. Monnier; P. G. Tuthill; W. C. Danchi

    2002-02-16

    The eccentric WR+O binary system WR 140 produces dust for a few months at intervals of 7.94 yrs coincident with periastron passage. We present the first resolved images of this dust shell, at binary phases ~0.039 and ~0.055, using aperture masking techniques on the Keck-I telescope to achieve diffraction-limited resolution. Proper motions of approximately 1.1 milliarcsecond per day were detected, implying a distance ~1.5 kpc from the known wind speed. The dust plume observed is not as simple as the ``pinwheel'' nebulae seen around other WR colliding wind binaries, indicating the orbital plane is highly inclined to our line-of-sight and/or the dust formation is very clumpy. Follow-up imaging in the mid-infrared and with adaptive optics is urgently required to track the dust motion further, necessary for unambiguously determining the orbital geometry which we only partially constrain here. With full knowledge of the orbital elements, these infrared images can be used to reconstruct the dust distribution along the colliding wind interface, providing a unique tool for probing the post-shock physical conditions of violent astrophysical flows.

  1. Signatures of recent asteroid disruptions in the formation and evolution of solar system dust bands

    E-Print Network [OSTI]

    Kehoe, A J Espy; Colwell, J E; Dermott, S F

    2015-01-01

    We have performed detailed dynamical modeling of the structure of a faint dust band observed in coadded IRAS data at an ecliptic latitude of 17$^{\\circ}$ that convincingly demonstrates that it is the result of a relatively recent (significantly less than 1 Ma) disruption of an asteroid and is still in the process of forming. We show here that young dust bands retain information on the size distribution and cross-sectional area of dust released in the original asteroid disruption, before it is lost to orbital and collisional decay. We find that the Emilkowalski cluster is the source of this partial band and that the dust released in the disruption would correspond to a regolith layer $\\sim$3 m deep on the $\\sim$10 km diameter source body's surface. The dust in this band is described by a cumulative size-distribution inverse power-law index with a lower bound of 2.1 (implying domination of cross-sectional area by small particles) for dust particles with diameters ranging from a few $\\mu$m up to a few cm. The co...

  2. Dust and Polycyclic Aromatic Hydrocarbon in the HD 34700 Debris Disk

    E-Print Network [OSTI]

    Seok, Ji Yeon

    2015-01-01

    The debris disk around the Vega-type star HD 34700 is detected in dust thermal emission from the near infrared (IR) to millimeter (mm) and submm wavelength range. Also detected is a distinct set of emission features at 3.3, 6.2, 7.7, 8.6, 11.3 and 12.7 $\\mu$m, which are commonly attributed to polycyclic aromatic hydrocarbon (PAH) molecules. We model the observed dust IR spectral energy distribution (SED) and PAH emission features of the HD 34700 disk in terms of porous dust and astronomical-PAHs. Porous dust together with a mixture of neutral and ionized PAHs closely explains the dust IR SED and PAH emission features observed in the HD 34700 disk. Due to the stellar radiation pressure and Poynting-Robertson drag together with the photodissociation of PAHs, substantial removal of dust and PAHs has occurred in the disk, and continuous replenishment of these materials is required to maintain their current abundances. This implies that these materials are not primitive but secondary products probably originating ...

  3. Can a photometric redshift code reliably determine dust extinction?

    E-Print Network [OSTI]

    T. S. R Babbedge; R. Whitaker; S. Morris

    2005-05-05

    Photometric redshifts can be routinely obtained to accuracies of better than 0.1 in Delta(z)/(1+z). However, the issue of dust extinction is one that has still not been well quantified. In this paper the success of two template-fitting photometric redshift codes (IMPZ and HYPERZ) at reliably returning Av in addition to redshift is explored. New data on the CNOC2 spectroscopic sample of 0.2

  4. Acid rain control strategists overlook dust removal benefits

    SciTech Connect (OSTI)

    Not Available

    1989-09-01

    Various strategies for controlling acid rain by reducing SO{sub 2} from existing utilities have failed to take into account the incidental particulate removal abilities of SO{sub 2} scrubbers. This has resulted in over-estimating the costs of acid rain control by 25% or more. This oversight has also caused utilities to invest in preliminary engineering of precipitator upgrades which will never have to be made if scrubbers are installed. While it seems inexplicable that a factor of this importance could have been overlooked by the industry, it is because of the unique situation in old U.S. utility power plants. These plants have relatively inefficient particulate control equipment which is not subject to new source performance standards. New power plants incorporate highly efficient particulate control devices so the ability of the downstream scrubbers to remove dust is irrelevant. The very small amount of particulate entering the scrubber from a highly efficient precipitator could be offset by escaping sulfate particles from a poorly operated scrubber. So an informal guideline was established to indicate that the scrubber had no overall effect on particulate emissions. The industry has generalized upon this guideline when, in fact, it only applies to new plants. The McIlvaine Company in its FGD Knowledge Network has thoroughly documented evidence that SO{sub 2} scrubbers will remove as much as 95% of the particulate being emitted from the relatively low efficiency precipitators operating on the nations existing coal-fired power plants.

  5. Dust properties of UV bright galaxies at z ~ 2

    E-Print Network [OSTI]

    S. Noll; D. Pierini

    2005-08-25

    We investigate the properties of the extinction curve in the rest-frame UV for a sample of 34 UV-luminous galaxies at 2 energy distribution is adopted; its sensitivity to properties of the stellar populations or of dust attenuation is established with the use of combined stellar population and radiative transfer models. The distribution of the z ~ 2 UV-luminous FDF galaxies in several diagnostic diagrams shows that their extinction curves range between those typical of the Small and Large Magellanic Clouds (SMC and LMC, respectively). For the majority of strongly reddened objects having a UV continuum slope beta > -0.4 a significant 2175 A absorption feature is inferred, indicating an LMC-like extinction curve. On the other hand, the UV continua of the least reddened objects are mostly consistent with SMC-like extinction curves, lacking a significant 2175 A bump, as for the Calzetti et al. sample of local starbursts. Furthermore, the most opaque (beta ~ 0) UV-luminous galaxies tend to be among the most metal rich, most massive, and largest systems at z ~ 2. The presence of the UV bump does not seem to depend on the total metallicity, as given by the equivalent width (EW) of the C IV doublet. Conversely, it seems to be associated with large EWs of prominent interstellar low-ionisation absorption lines, suggesting a link between the strength of the UV bump and the topology of the interstellar medium of the most evolved UV-luminous, massive galaxies at z ~ 2.

  6. The dust grain size - stellar luminosity trend in debris discs

    E-Print Network [OSTI]

    Pawellek, Nicole

    2015-01-01

    The cross section of material in debris discs is thought to be dominated by the smallest grains that can still stay in bound orbits despite the repelling action of stellar radiation pressure. Thus the minimum (and typical) grain size $s_\\text{min}$ is expected to be close to the radiation pressure blowout size $s_\\text{blow}$. Yet a recent analysis of a sample of Herschel-resolved debris discs showed the ratio $s_\\text{min}/s_\\text{blow}$ to systematically decrease with the stellar luminosity from about ten for solar-type stars to nearly unity in the discs around the most luminous A-type stars. Here we explore this trend in more detail, checking how significant it is and seeking to find possible explanations. We show that the trend is robust to variation of the composition and porosity of dust particles. For any assumed grain properties and stellar parameters, we suggest a recipe of how to estimate the "true" radius of a spatially unresolved debris disc, based solely on its spectral energy distribution. The r...

  7. Effects of Advanced Combustion Technologies on Particulate Matter...

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

    Advanced Combustion Technologies on Particulate Matter Emissions Characteristics Effects of Advanced Combustion Technologies on Particulate Matter Emissions Characteristics...

  8. Superconducting Detectors for Super Light Dark Matter

    E-Print Network [OSTI]

    Yonit Hochberg; Yue Zhao; Kathryn M. Zurek

    2015-04-27

    We propose and study a new class of of superconducting detectors which are sensitive to O(meV) electron recoils from dark matter-electron scattering. Such devices could detect dark matter as light as the warm dark matter limit, mX > keV. We compute the rate of dark matter scattering off free electrons in a (superconducting) metal, including the relevant Pauli blocking factors. We demonstrate that classes of dark matter consistent with all astrophysical and terrestrial constraints could be detected by such detectors with a moderate size exposure.

  9. Superconducting Detectors for Super Light Dark Matter

    E-Print Network [OSTI]

    Hochberg, Yonit; Zurek, Kathryn M

    2015-01-01

    We propose and study a new class of of superconducting detectors which are sensitive to O(meV) electron recoils from dark matter-electron scattering. Such devices could detect dark matter as light as the warm dark matter limit, mX > keV. We compute the rate of dark matter scattering off free electrons in a (superconducting) metal, including the relevant Pauli blocking factors. We demonstrate that classes of dark matter consistent with all astrophysical and terrestrial constraints could be detected by such detectors with a moderate size exposure.

  10. Superconducting Detectors for Super Light Dark Matter

    E-Print Network [OSTI]

    Yonit Hochberg; Yue Zhao; Kathryn M. Zurek

    2015-11-11

    We propose and study a new class of superconducting detectors which are sensitive to O(meV) electron recoils from dark matter-electron scattering. Such devices could detect dark matter as light as the warm dark matter limit, mX > keV. We compute the rate of dark matter scattering off of free electrons in a (superconducting) metal, including the relevant Pauli blocking factors. We demonstrate that classes of dark matter consistent with terrestrial and cosmological/astrophysical constraints could be detected by such detectors with a moderate size exposure.

  11. Incompressibility of asymmetric nuclear matter

    E-Print Network [OSTI]

    Lie-Wen Chen; Bao-Jun Cai; Chun Shen; Che Ming Ko; Jun Xu; Bao-An Li

    2009-11-17

    The incompressibility $K_sat(\\delta)$ of isospin asymmetric nuclear matter at its saturation density. Our results show that in the expansion of $K_sat(\\delta)$ in powers of isospin asymmetry $\\delta$, i.e., $K_sat(\\delta )$=K_{0}+K_{sat,2}\\delta^{2}+K_{sat,4}\\delta^{4}+O(\\delta^{6})$, the magnitude of the 4th-order K_{sat,4} parameter is generally small. The 2nd-order K_{sat,2} parameter thus essentially characterizes the isospin dependence of the incompressibility of asymmetric nuclear matter at saturation density. Furthermore, the K_{sat,2} can be expressed as K_{sat,2}=K_{sym}-6L-J_{0}/{K_{0}L in terms of the slope parameter $L$ and the curvature parameter $K_{\\mathrm{sym}}$ of the symmetry energy and the third-order derivative parameter $J_0$ of the energy of symmetric nuclear matter at saturation density, and we find the higher order $J_0$ contribution to K_{sat,2} generally cannot be neglected. Also, we have found a linear correlation between K_{sym} and $L$ as well as between $J_{0}/K_{0}$ and $K_{0}$. Using these correlations together with the empirical constraints on $K_{0}$ and $L$, the nuclear symmetry energy $E_sym(\\rho_{0})$ at normal nuclear density, and the nucleon effective mass, we have obtained an estimated value of K_{sat,2}=-370 +- 120 MeV for the 2nd-order parameter in the isospin asymmetry expansion of the incompressibility of asymmetric nuclear matter at its saturation density.

  12. Two-portal Dark Matter

    E-Print Network [OSTI]

    Karim Ghorbani; Hossein Ghorbani

    2015-06-14

    We propose a renormalizable dark matter model in which a fermionic dark matter (DM) candidate communicates with the standard model particles through two distinct portals: Higgs and vector portals. The dark sector is charged under a $U(1)'$ gauge symmetry while the standard model has a leptophobic interaction with the dark vector boson. The leading contribution of DM-nucleon elastic scattering cross section begins at one-loop level. The model meets all the constraints imposed by direct detection experiments provided by LUX and XENON100, observed relic abundance according to WMAP and Planck, and the invisible Higgs decay width measured at the LHC. It turns out that the dark matter mass in the viable parameter space can take values from a few GeV up to 1 TeV. This is a new feature which is absent in the models with only one portal. In addition, we can find in the constrained regions of the parameter space a DM mass of $\\sim 34$ GeV annihilating into $b$ quark pair, which explains the Fermi-LAT gamma-ray excess.

  13. On Math, Matter and Mind

    E-Print Network [OSTI]

    Piet Hut; Mark Alford; Max Tegmark

    2006-01-15

    We discuss the nature of reality in the ontological context of Penrose's math-matter-mind triangle. The triangle suggests the circularity of the widespread view that math arises from the mind, the mind arises out of matter, and that matter can be explained in terms of math. Non-physicists should be wary of any claim that modern physics leads us to any particular resolution of this circularity, since even the sample of three theoretical physicists writing this paper hold three divergent views. Some physicists believe that current physics has already found the basic framework for a complete description of reality, and only has to fill in the details. Others suspect that no single framework, from physics or other sources, will ever capture reality. Yet others guess that reality might be approached arbitrarily closely by some form of future physics, but probably based on completely different frameworks. We will designate these three approaches as the fundamentalist, secular and mystic views of the world, as seen by practicing physicists. We present and contrast each of these views, which arguably form broad categories capturing most if not all interpretations of physics. We argue that this diversity in the physics community is more useful than an ontological monoculture, since it motivates physicists to tackle unsolved problems with a wide variety of approaches.

  14. Heavy Dark Matter Through the Higgs Portal

    E-Print Network [OSTI]

    John March-Russell; Stephen M. West; Daniel Cumberbatch; Dan Hooper

    2008-06-17

    Motivated by Higgs Portal and Hidden Valley models, heavy particle dark matter that communicates with the supersymmetric Standard Model via pure Higgs sector interactions is considered. We show that a thermal relic abundance consistent with the measured density of dark matter is possible for masses up to $\\sim 30\\tev$. For dark matter masses above $\\sim 1\\tev$, non-perturbative Sommerfeld corrections to the annihilation rate are large, and have the potential to greatly affect indirect detection signals. For large dark matter masses, the Higgs-dark-matter-sector couplings are large and we show how such models may be given a UV completion within the context of so-called "Fat-Higgs" models. Higgs Portal dark matter provides an example of an attractive alternative to conventional MSSM neutralino dark matter that may evade discovery at the LHC, while still being within the reach of current and upcoming indirect detection experiments.

  15. 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]

    Dalziel, Stuart

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

  16. Dust and gas in luminous proto-cluster galaxies at z=4.05: the case for different cosmic dust evolution in normal and starburst galaxies

    E-Print Network [OSTI]

    Tan, Q; Magdis, G; Pannella, M; Sargent, M; Riechers, D; Béthermin, M; Bournaud, F; Carilli, C; da Cunha, E; Dannerbauer, H; Dickinson, M; Elbaz, D; Gao, Y; Hodge, J; Owen, F; Walter, F

    2014-01-01

    We measure the dust and gas content of the three sub-millimeter galaxies (SMGs) in the GN20 proto-cluster at $z=4.05$ using new IRAM Plateau de Bure interferometer (PdBI) CO(4-3) and 1.2-3.3mm continuum observations. All these three SMGs are heavily dust obscured, with UV-based star formation rate (SFR) estimates significantly smaller than the ones derived from the bolometric IR, consistent with the spatial offsets revealed by HST and CO imaging. Based also on evaluations of the specific SFR, CO-to-H$_2$ conversion factor and gas depletion timescale, we classify all the three galaxies as starbursts (SBs), although with a lower confidence for GN20.2b that might be a later stage merging event. We place our measurements in the context of the evolutionary properties of main sequence (MS) and SB galaxies. ULIRGs have 3-5 times larger $L'_{\\rm CO}/M_{\\rm dust}$ and $M_{\\rm dust}/M_\\star$ ratios than $z=0$ MS galaxies, but by $z\\sim2$ the difference appears to be blurred, probably due to differential metallicity evo...

  17. Benchmarking the Calculation of Stochastic Heating and Emissivity of Dust Grains in the Context of Radiative Transfer Simulations

    E-Print Network [OSTI]

    Camps, Peter; Bianchi, Simone; Lunttila, Tuomas; Pinte, Christophe; Natale, Giovanni; Juvela, Mika; Fischera, Joerg; Fitzgerald, Michael P; Gordon, Karl; Baes, Maarten; Steinacker, Juergen

    2015-01-01

    We define an appropriate problem for benchmarking dust emissivity calculations in the context of radiative transfer (RT) simulations, specifically including the emission from stochastically heated dust grains. Our aim is to provide a self-contained guide for implementors of such functionality, and to offer insights in the effects of the various approximations and heuristics implemented by the participating codes to accelerate the calculations. The benchmark problem definition includes the optical and calorimetric material properties, and the grain size distributions, for a typical astronomical dust mixture with silicate, graphite and PAH components; a series of analytically defined radiation fields to which the dust population is to be exposed; and instructions for the desired output. We process this problem using six RT codes participating in this benchmark effort, and compare the results to a reference solution computed with the publicly available dust emission code DustEM. The participating codes implement...

  18. Nonlinear dust acoustic waves and shocks R. L. Merlino, J. R. Heinrich, S.-H. Hyun, and J. K. Meyer

    E-Print Network [OSTI]

    Merlino, Robert L.

    Nonlinear dust acoustic waves and shocks R. L. Merlino, J. R. Heinrich, S.-H. Hyun, and J. K. Meyer, 032110 (2012) Planar and non-planar dust ion-acoustic solitary waves in a quantum dusty electronegative://pop.aip.org/about/rights_and_permissions #12;Nonlinear dust acoustic waves and shocksa) R. L. Merlino,b) J. R. Heinrich, S.-H. Hyun, and J. K

  19. A motivational interviewing intervention to PREvent PAssive Smoke Exposure (PREPASE) in children with a high risk of asthma: design of a randomised controlled trial

    E-Print Network [OSTI]

    2013-01-01

    reduce passive smoke exposure in low-income households withHousehold nicotine levels are measured (at baseline and 12 months after baseline) by placing a passive

  20. Application of the Supported Fluorescent Probe Proxyl Fluorescamine to the Measurement of Free Radicals in Cigarette Smoke and Secondary Organic Aerosols

    E-Print Network [OSTI]

    Sleiman, Mohamad

    2013-01-01

    V. Rehan, P. Talbot, S. Schick, J. Samet, Y. Wang, B. Hang,Health Perspectives 2011, S. Schick. Thirdhand smoke: Here