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The Inflammability of Illinois Coal Dusts

Description: From Introduction: "The present paper is a report of a detailed study of the bituminous dusts of Illinois mines, and is a part of the investigations conducted by the bureau in cooperation with the Illinois State Geological Survey and the department of mining engineering of the University of Illinois."
Date: 1916
Creator: Clement, J. K. & Scholl, L. A., Jr.
Partner: UNT Libraries Government Documents Department

Laboratory Studies of the Inflammability of Coal Dusts: Effect of Fineness of Coal and Inert Dusts on the Inflammability of Coal Dusts

Description: From Introduction: "The work reported in this paper is part of a program of laboratory studies of inflammability of coal dusts started before the Bureau of Mines became a separate organization in 1910."
Date: 1935
Creator: Godbert, A. L. & Greenwald, H. P.
Partner: UNT Libraries Government Documents Department

Coal-Dust Explosion Tests in the Experimental Mine, 1919 to 1924, Inclusive

Description: From Introduction and Summary: "This bulletin describes the third series of coal-dust explosion tests by the Bureau of Mines in its experimental mine and covers a period from 1919 to the end of 1924, inclusive. A few related tests made in 1925 are also included."
Date: 1927
Creator: Rice, George S.; Paul, J. W. & Greenwald, H. P.
Partner: UNT Libraries Government Documents Department

Review of Literature on Dusts

Description: From Introduction: "Problems connected with incidence, effects, determination, and control of dusts are still much before the public, although more information is available to the layman than when Bulletin 400, of which this publication is a revision, was issued in 1937. This revision includes data that have accumulated since 1937 and some that appeared previous thereto but were not available to the authors at that time."
Date: 1950
Creator: Forbes, J. J.; Davenport, Sara J. & Morgis, Genevieve
Partner: UNT Libraries Government Documents Department

PROCESS ENGINEERING REPORT ON REVISED PROCESS DESIGN TRANSMITTAL, GREEN SALT PLANT, JOB NO. 3004 OF THE FEED MATERIALS PRODUCTION CENTER, FERNALD, OHIO. Specifications Contract No. 3000, Part XXV, Section 4

Description: Process design information concerning equipment and operation of a plant to produce UF/sub 4/ from UO/sub 3/ is presented. Included are process flow diagrams, drawings of ventilation and dust control systems, and vent gas systenas. Equipment lists and estimated utilities are also included as well as a description of the process. (J.R.D.)
Date: June 1, 1952
Creator: Holby, G.V. & James, F.
Partner: UNT Libraries Government Documents Department

Dust Sources and Controls for Multiple-Machine Longwall Faces

Description: Abstract: Longwall mining in lower seam heights may necessitate the use of single-drum shearers to overcome size constraints associated with standard double-drum shearers. To avoid the operational problem of clearance in the tailgate entry with one single-drum shearer, two single-drum machines can be operated on the same face, with each shearer responsible for mining a predefined portion of the face. However, utilization of two shearers on the same face necessitates the positioning of one shearer operator and a jacksetter in the return air of the upwind shearer, thus complicating respirable dust control on the longwall. In an effort to evaluate the unique dust control problems associated with this type of mining, the U.S. Bureau of Mines conducted dust surveys on two multiple-machine longwall operations. Sampling was done to quantify major sources of respirable dust and to identify potential solutions to problem areas. Sampling results indicate that the cutting sequences utilized on multiple-machine faces may have to be designed to minimize dust exposure, as opposed to optimizing productivity or facilitating operational requirements. Also, state-of-the-art dust control techniques typically found on double-drum shearer longwalls must be employed to help minimize the exposure of all face personnel to traditional dust sources.
Date: 1995
Creator: Colinet, Jay F. & Spencer, Ellsworth R.
Partner: UNT Libraries Government Documents Department

Dust Plume Modeling at Fort Bliss: Move-Out Operations, Combat Training and Wind Erosion

Description: The potential for air-quality impacts from heavy mechanized vehicles operating in the training ranges and on the unpaved main supply routes at Fort Bliss was investigated. This report details efforts by the staff of Pacific Northwest National Laboratory for the Fort Bliss Directorate of Environment in this investigation. Dust emission and dispersion from typical activities, including move outs and combat training, occurring on the installation were simulated using the atmospheric modeling system DUSTRAN. Major assumptions associated with designing specific modeling scenarios are summarized, and results from the simulations are presented.
Date: September 29, 2006
Creator: Chapman, Elaine G.; Rishel, Jeremy P.; Rutz, Frederick C.; Seiple, Timothy E.; Newsom, Rob K. & Allwine, K Jerry
Partner: UNT Libraries Government Documents Department

Dust Plume Modeling from Ranges and Maneuver Areas on Fort Bliss and the White Sands Missile Range: Final Report

Description: The potential for air quality impacts from heavy mechanized vehicles operating on and between the unpaved main supply routes at Fort Bliss and White Sands Missile Range was investigated. This report details efforts by the staff of Pacific Northwest National Laboratory for the Fort Bliss Directorate of Environment in this investigation. Dust emission and dispersion from typical move-out activities occurring on the installations were simulated using the atmospheric modeling system DUSTRAN. Major assumptions associated with designing the modeling scenarios are summarized and results of simulations conducted under these assumptions are presented for four representative meteorological periods.
Date: May 4, 2009
Creator: Chapman, Elaine G.; Barnard, James C.; Rutz, Frederick C.; Pekour, Mikhail S.; Rishel, Jeremy P. & Shaw, William J.
Partner: UNT Libraries Government Documents Department

Three-dimensional Reconstruction of Dust Particle Trajectories in the NSTX

Description: Highly mobile incandescent dust particles are routinely observed on NSTX using two fast cameras operating in the visible region. An analysis method to reconstruct dust particle trajectories in space using two fast cameras is presented in this paper. Position accuracies of a few millimeters depending on the particle's location have been achieved and particle velocities between 10 and 200 m/s have been observed. 2008 American Institute of Physics. __________________________________________________
Date: March 6, 2009
Creator: Boeglin, W. U.; Roquemore, A. L. & Maqueda, R.
Partner: UNT Libraries Government Documents Department

Recovering the Elemental Composition of Comet Wild 2 Dust in Five Stardust Impact Tracks and Terminal Particles in Aerogel

Description: The elemental (non-volatile) composition of five Stardust impact tracks and terminal particles left from capture of Comet 81P/Wild 2 dust were mapped in a synchrotron x-ray scanning microprobe with full fluorescence spectra at each pixel. Because aerogel includes background levels of several elements of interest, we employ a novel 'dual threshold' approach to discriminate against background contaminants: an upper threshold, above which a spectrum contains cometary material plus aerogel and a lower threshold below which it contains only aerogel. The difference between normalized cometary-plus-background and background-only spectra is attributable to cometary material. The few spectra in between are discarded since misallocation is detrimental: cometary material incorrectly placed in the background spectrum is later subtracted from the cometary spectrum, doubling the loss of reportable cometary material. This approach improves precision of composition quantification. We present the refined whole impact track and terminal particle elemental abundances for the five impact tracks. One track shows mass increases in Cr and Mn (1.4x), Cu, As and K (2x), Zn (4x) and total mass (13%) by dual thresholds compared to a single threshold. Major elements Fe and Ni are not significantly affected. The additional Cr arises from cometary material containing little Fe. We exclude Au intermixed with cometary material because it is found to be a localized surface contaminant carried by comet dust into an impact track. The dual threshold technique can be used in other situations where elements of interest in a small sample embedded in a matrix are also present in the matrix itself.
Date: January 4, 2007
Creator: Ishii, H A; Brennan, S; Bradley, J P; Luening, K; Ignatyev, K & Pianetta, P
Partner: UNT Libraries Government Documents Department

Comparison of the oxidation state of Fe in comet 81P/Wild 2 and chondritic-porous interplanetary dust particles

Description: The fragile structure of chondritic-porous interplanetary dust particles (CP-IDPs) and their minimal parent-body alteration have led researchers to believe these particles originate in comets rather than asteroids where aqueous and thermal alterations have occurred. The solar elemental abundances and atmospheric entry speed of CP-IDPs also suggest a cometary origin. With the return of the Stardust samples from Jupiter-family comet 81P/Wild 2, this hypothesis can be tested. We have measured the Fe oxidation state of 15 CP-IDPs and 194 Stardust fragments using a synchrotron-based x-ray microprobe. We analyzed {approx}300 ng of Wild 2 material - three orders of magnitude more material than other analyses comparing Wild 2 and CP-IDPs. The Fe oxidation state of these two samples of material are > 2{sigma} different: the CP-IDPs are more oxidized than the Wild 2 grains. We conclude that comet Wild 2 contains material that formed at a lower oxygen fugacity than the parent-body, or parent bodies, of CP-IDPs. If all Jupiter-family comets are similar, they do not appear to be consistent with the origin of CP-IDPs. However, comets that formed from a different mix of nebular material and are more oxidized than Wild 2 could be the source of CP-IDPs.
Date: July 16, 2010
Creator: Ogliore, Ryan C.; Butterworth, Anna L.; Fakra, Sirine C.; Gainsforth, Zack; Marcus, Matthew A. & Westphal, Andrew J.
Partner: UNT Libraries Government Documents Department

Multi-color light curves of type Ia supernovae on thecolor-magnitude diagram: A novel step toward more precise distance andextinction estimates

Description: We show empirically that fits to the color-magnituderelation of Type Ia supernovae after optical maximum can provide accuraterelative extragalactic distances. We report the discovery of an empiricalcolor relation for Type Ia light curves: During much of the first monthpast maximum, the magnitudes of Type Ia supernovae defined at a givenvalue of color index have a very small magnitude dispersion; moreover,during this period the relation between B magnitude and B-V color (or B-Ror B-I color) is strikingly linear, to the accuracy of existingwell-measured data. These linear relations can provide robust distanceestimates, in particular, by using the magnitudes when the supernovareaches a given color. After correction for light curve stretch factor ordecline rate, the dispersion of the magnitudes taken at the intercept ofthe linear color-magnitude relation are found to be around 0^m .08 forthe sub-sample of supernovae with (B_max - V_max) ?= 0^m 0.5, andaround 0^m.11 for the sub-sample with (B_max - V_max) ?= 0^m .2.This small dispersion is consistent with being mostly due toobservational errors. The method presented here and the conventionallight curve fitting methods can be combined to further improvestatistical dispersions of distance estimates. It can be combined withthe magnitude at maximum to deduce dust extinction. Theslopes of thecolor-magnitude relation may also be used to identify intrinsicallydifferent SN Ia systems. The method provides a tool that is fundamentalto using SN Ia to estimate cosmological parameters such as the Hubbleconstant and the mass and dark energy content of theuniverse.
Date: January 31, 2003
Creator: Wang, Lifan; Goldhaber, Gerson; Aldering, Greg & Perlmutter, Saul
Partner: UNT Libraries Government Documents Department

A STUDY OF FISCHER 344 RATS EXPOSED TO SILICA DUST FOR SIX MONTHS AT CONCENTRATIONS OF 0, 2, 10 OR 20 MG / M3.

Description: The major objective of this study was to relate the results of a series of functional tests to the compositional and structural alterations in the rat lung induced by subchronic exposure to silica dust. Fischer-344 rats were exposed for 6 hours/day, 5 days/week for 6 months to either 0, 2, 10, or 20 mg SiO{sub 2}/m{sup 3}. The general appearance of the exposed rats was not different from that of the controls. Interestingly, female rats exposed to silica dust, at all tested concentrations, gained more weight than the controls. The lung weight and the lung-to-body weight ratio was greater in the male rats exposed to the highest concentration of silica dust.
Date: February 1, 1984
Creator: KUTZMAN,R.S.
Partner: UNT Libraries Government Documents Department

Control of Metallurgical and mineral dusts and fumes in Los Angeles County, California

Description: Report issued by the U.S. Bureau of Mines discussing metallurgical and mineral fumes and dusts in Los Angeles County, California. Properties of dusts and fumes from different minerals are presented. This report includes tables, maps, illustrations, and photographs.
Date: April 1952
Creator: Allen, Glenn L.; Viets, Floyd H. & McCabe, Louis C.
Partner: UNT Libraries Government Documents Department

Dust-Plasma

Description: Our theoretical research on dust-plasma interactions has concentrated on three main areas: a)studies of grain charging and applications; b) waves and instabilities in weakly correlated dusty plasma with applications to space and laboratory plasmas; c) waves in strongly coupled dusty plasmas.
Date: February 22, 2005
Creator: Rosenberg, Marelene
Partner: UNT Libraries Government Documents Department

Drilling and Dustiness of Metal-Mine Air

Description: Report issued by the U.S. Bureau of Mines on the air quality in metal-mines after using wet drills. Dust samples are collected and compared to samples collected from similar metal-mines in South Africa and Australia. This report includes tables.
Date: March 1922
Creator: Harrington, D.
Partner: UNT Libraries Government Documents Department

Measuring Type Ia Supernova Distances and Redshifts From TheirMulti-band Light Curves

Description: The distance and redshift of a type Ia supernova can bedetermined simultaneously through its multi-band light curves. This factmay beused for imaging surveys that discover and obtain photometry forlarge numbers of supernovae; so many that it would be difficult to obtaina spectroscopic redshift for each. Using available supernova-analysistools we find that there are several conditions in which a viabledistance--redshift can be determined. Uncertainties in the effectivedistance at z~;0.3 are dominated by redshift uncertainties coupled withthe steepness of the Hubble law. By z~;0.5 the Hubble law flattens outand distance-modulus uncertainties dominate. Observations that giveS/N=50 at peak brightness and a four-day observer cadence in each ofgriz-bands are necessary to match the intrinsic supernova magnitudedispersion out to z=1.0. Lower S/N can be tolerated with the addition ofredshift priors (e.g., from a host-galaxy photometric redshift),observationsin an additional redder band, or by focusing on supernovaredshifts that have particular leverage for this measurement. Morestringent S/N requirements are anticipated as improved systematicscontrol over intrinsic color, metallicity, and dust is attempted to bedrawn from light curves.
Date: August 12, 2007
Creator: Kim, Alex G. & Miquel, Ramon
Partner: UNT Libraries Government Documents Department

Clouds and Chemistry in the Atmosphere of Extrasolar Planet HR8799b

Description: Using the integral field spectrograph OSIRIS, on the Keck II telescope, broad near-infrared H and K-band spectra of the young exoplanet HR8799b have been obtained. In addition, six new narrow-band photometric measurements have been taken across the H and K bands. These data are combined with previously published photometry for an analysis of the planet's atmospheric properties. Thick photospheric dust cloud opacity is invoked to explain the planet's red near-IR colors and relatively smooth near-IR spectrum. Strong water absorption is detected, indicating a Hydrogen-rich atmosphere. Only weak CH{sub 4} absorption is detected at K band, indicating efficient vertical mixing and a disequilibrium CO/CH{sub 4} ratio at photospheric depths. The H-band spectrum has a distinct triangular shape consistent with low surface gravity. New giant planet atmosphere models are compared to these data with best fitting bulk parameters, T{sub eff} = 1100K {+-} 100 and log(g) = 3.5 {+-} 0.5 (for solar composition). Given the observed luminosity (log L{sub obs}/L{sub {circle_dot}} {approx} -5.1), these values correspond to a radius of 0.75 R{sub Jup{sub 0.12}{sup +0.17}} and mass {approx} 0.72 M{sub Jup{sub -0.6}{sup +2.6}} - strikingly inconsistent with interior/evolution models. Enhanced metallicity (up to {approx} 10 x that of the Sun) along with thick clouds and non-equilibrium chemistry are likely required to reproduce the complete ensemble of spectroscopic and photometric data and the low effective temperatures (< 1000K) required by the evolution models.
Date: March 21, 2011
Creator: Barman, T. S.; Macintosh, B. A.; Konopacky, Q. M. & Marois, C.
Partner: UNT Libraries Government Documents Department

Atmospheric Properties from the 2006 Niamey Deployment and Climate Simulation with a Geodesic Grid Coupled Climate Model

Description: In 2008, the Atmospheric Radiation Measurement (ARM) Program and the Climate Change Prediction Program (CCPP) have been asked to produce joint science metrics. For CCPP, the metrics will deal with a decade-long control simulation using geodesic grid-coupled climate model. For ARM, the metrics will deal with observations associated with the 2006 deployment of the ARM Mobile Facility (AMF) to Niamey, Niger. Specifically, ARM has been asked to deliver data products for Niamey that describe cloud, aerosol, and dust properties.
Date: March 1, 2008
Creator: Jensen, M; Johnson, K; Mather, J & Randall, D
Partner: UNT Libraries Government Documents Department

THE INHALATION TOXICITY OF INDIUM SESQUIOXIDE IN THE RAT

Description: Albino rats were exposed to a In/sub 2/O/sub 3/ dust aerosol of mean concentration 64 mg/m) for 3 months. The retention of In in the tissues and the mobilization of In from the lungs and tracheobronchlal lymph nodes were determined. The results indicate chemical toxicity. (D.L.C.)
Date: February 10, 1961
Creator: Leach, L.J.; Scott, J.K.; Armstrong, R.D. & Steadman, L.T.f Maynard, E.A.
Partner: UNT Libraries Government Documents Department

Atmospheric Properties from the 2006 Niamey Deployment and Climate Simulation with a Geodesic Grid Coupled Climate Model - First Quarter 2008

Description: In 2008, the Atmospheric Radiation Measurement (ARM) program and the Climate Change Prediction Program (CCPP) have been asked to produce joint science metrics. For CCPP, the metrics will deal with a decade-long control simulation using geodesic grid-coupled climate model. For ARM, the metrics will deal with observations associated with the 2006 deployment of the ARM Mobile Facility (AMF) to Niamey, Niger. Specifically, ARM has been asked to deliver data products for Niamey that describe cloud, aerosol, and dust properties. The first quarter milestone is ‘initial formulation of the algorithm to produce and make available, new continuous time series of retrieved cloud , aerosol and dust properties, based on results from the ARM Mobile Facility deployment in Niger, Africa. The first quarter milestone has been achieved.
Date: December 30, 2007
Creator: Mather, J. H. & Randall, D.
Partner: UNT Libraries Government Documents Department

Atmospheric Properties from the 2006 Niamey Deployment and Climate Simulation with a Geodesic Grid Coupled Climate Model Fourth Quarter 2008

Description: In 2008, the Atmospheric Radiation Measurement (ARM) Program and the Climate Change Prediction Program (CCPP) have been asked to produce joint science metrics. For CCPP, the metrics will deal with a decade-long control simulation using geodesic grid-coupled climate model. For ARM, the metrics will deal with observations associated with the 2006 deployment of the ARM Mobile Facility (AMF) to Niamey, Niger. Specifically, ARM has been asked to deliver data products for Niamey that describe cloud, aerosol, and dust properties. The first quarter milestone was the initial formulation of the algorithm for retrieval of these properties. The second quarter milestone included the time series of ARM-retrieved cloud properties and a year-long CCPP control simulation. The third quarter milestone included the time series of ARM-retrieved aerosol optical depth and a three-year CCPP control simulation. This final fourth quarter milestone includes the time-series of aerosol and dust properties and a decade-long CCPP control simulation.
Date: September 30, 2008
Creator: Mather, JH; Randall, DA & Flynn, CJ
Partner: UNT Libraries Government Documents Department