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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

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

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

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

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

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

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

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

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

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

Preliminary field evaluation of high efficiency steel filters

Description: The authors have conducted an evaluation of two high efficiency steel filters in the exhaust of an uranium oxide grit blaster at the Y-12 Plant in Oak Ridge Tennessee. The filters were installed in a specially designed filter housing with a reverse air-pulse cleaning system for automatically cleaning the filters in-place. Previous tests conducted on the same filters and housing at LLNL under controlled conditions using Arizona road dust showed good cleanability with reverse air pulses. Two high efficiency steel filters, containing 64 pleated cartridge elements housed in the standard 2{prime} x 2{prime} {times} l{prime} HEPA frame, were evaluated in the filter test housing using a 1,000 cfm slip stream containing a high concentration of depleted uranium oxide dust. One filter had the pleated cartridges manufactured to the authors specifications by the Pall Corporation and the other by Memtec Corporation. Test results showed both filters had a rapid increase in pressure drop with time, and reverse air pulses could not decrease the pressure drop. The authors suspected moisture accumulation in the filters was the problem since there were heavy rains during the evaluations, and the pressure drop of the Memtec filter decreased dramatically after passing clean, dry air through the filter and after the filter sat idle for one week. Subsequent laboratory tests on a single filter cartridge confirmed that water accumulation in the filter was responsible for the increase in filter pressure drop and the inability to lower the pressure drop by reverse air pulses. No effort was made to identify the source of the water accumulation and correct the problem because the available funds were exhausted.
Date: November 1, 1994
Creator: Bergman, W.; Larsen, G.; Lopez, R.; Wilson, K.; Simon, K. & Frye, L.
Partner: UNT Libraries Government Documents Department

ADVANCED HYBRID PARTICULATE COLLECTOR

Description: A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and re-collection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hr parametric tests and 100-hr proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency. Since all of the developmental goals of Phase I were met, the approach was scaled up in Phase II to a size of 255 m{sup 3}/min (9000 acfm) (equivalent in size to 2.5 MW) and was installed on a slipstream at the Big Stone Power Plant. For Phase II, the AHPC at Big Stone Power Plant was operated continuously from late July 1999 until mid-December 1999. The Phase II results were highly successful in that ultrahigh particle collection efficiency was achieved, pressure drop was well controlled, and system operability was excellent. For Phase III, the AHPC was modified into a more compact configuration, and components were installed that were closer to what would be used in a full-scale commercial design. The modified AHPC was operated from April to July 2000. While operational results were acceptable during this time, inspection of bags in the summer of 2000 revealed some membrane damage to the ...
Date: December 1, 2001
Creator: Zhuang, Ye; Miller, Stanley J.; Olderbak, Michelle R. & Gebert, Rich
Partner: UNT Libraries Government Documents Department

ADVANCED HYBRID PARTICULATE COLLECTOR - PHASE III

Description: A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration. The AHPC concept consists of a combination of fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. In Phase II, a 2.5-MW-scale AHPC was designed, constructed, installed, and tested at the Big Stone power plant. For Phase III, further testing of an improved version of the 2.5-MW-scale AHPC at the Big Stone power plant is being conducted to facilitate commercialization of the AHPC technology.
Date: April 1, 2001
Creator: Miller, Stanley J.; Zhuang, Ye & Olderbak, Michelle R.
Partner: UNT Libraries Government Documents Department

ADVANCED HYBRID PARTICULATE COLLECTOR - PHASE III

Description: A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration. The AHPC concept consists of a combination of fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. In Phase II, a 2.5-MW-scale AHPC was designed, constructed, installed, and tested at the Big Stone power station. For Phase III, further testing of an improved version of the 2.5-MW-scale AHPC at the Big Stone power station is planned to facilitate commercialization of the AHPC technology.
Date: May 1, 2000
Creator: Miller, Stanley J. & Collings, Michael E.
Partner: UNT Libraries Government Documents Department

Carbon Formation and Metal Dusting in Hot-Gas Cleanup Systems of Coal Gasifiers

Description: There are several possible materials/systems degradation modes that result from gasification environments with appreciable carbon activities. These processes, which are not necessarily mutually exclusive, include carbon deposition, carburization, metal dusting, and CO disintegration of refractories. Carbon formation on solid surfaces occurs by deposition from gases in which the carbon activity (a sub C) exceeds unity. The presence of a carbon layer CO can directly affect gasifier performance by restricting gas flow, particularly in the hot gas filter, creating debris (that may be deposited elsewhere in the system or that may cause erosive damage of downstream components), and/or changing the catalytic activity of surfaces.
Date: December 31, 1995
Creator: Tortorelli, Peter F.; Judkins, Roddie R.; DeVan, Jackson H. & Wright, Ian G.
Partner: UNT Libraries Government Documents Department

Search for technetium in natural tin metallurgical residues

Description: Possible instability of baryons inside the nuclei might result in accumulation of rare isotopes in natural ores. In this respect, isotopes of technetium have certain advantages that can be useful in the search for technetium in nonradioactive ores by chemical methods. In this paper, we review the history of technetium research and discuss a new approach to the search for natural technetium associated with tin ores which appears to offer a rare possibility of discovering a smelting operation by-product such as flue dust, in which the volatile technetium heptoxide (Tc{sub 2}O{sub 7}), like rhenium heptoxide (Re{sub 2}O{sub 7}), would be expected to concentrate. Our concept of a search for technetium in these materials would be based on the assumption that traces of rhenium could occur in the ore and could be traced most easily by neutron activation of small samples. Such a procedure would confirm that an enrichment from the ore to the flue dust actually occurs with the rhenium and therefore should occur with technetium. Furthermore, this occurrence should identify the best location to search for technetium.
Date: July 1, 1996
Creator: Parker, C.W.
Partner: UNT Libraries Government Documents Department