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By P. G. Clites

This study was conducted to determine the patterns of heat transfer to water-cooled copper crucibles during vacuum arc melting. Values of heat flux from the ingot to the crucible were determined during nonconsumable electrode vacuum arc melting of zirconium and during consumable electrode vacuum arc melting of titanium) zirconium) and steel. The results of these studies con-firm the existence of a high thermal resistance between the ingot and the crucible wall which results from the shrinkage of the ingot as the metal solidifies. Maximum heat flux occurs near the top of the ingot where maximum values of heat flux of 1.4 X 106 Btu/ft2 hr were observed during small-scale consumable electrode arc melting of zirconium and titanium. The maximum heat flux for consumable electrode arc melting of 8-inch-diameter ingots was 0.5 X 106 Btu/ft2 hr. The effects of electrode material) electrode diameter) arc current) and arc potential on heat flux from the ingot to the crucible were studied. Data were also obtained on crucible wall temperatures and on the effect of very narrow annular water jackets.

Jan 1, 1967

By A. B. Hooler

"A complete list of permissible mine equipment, tested and approved by the Bureau of Mines previous to January 1, 1947, was published as Information Circular 7432. 3/The present list is a supplement thereto that includes all of the equipment approved during the calendar year 1947.The items are numbered to indicate the consecutive order in which each type of machine or device was approved in its particular classification. Thus, Information Circular 7432 showed six air compressors on the active list; two additional compressors, Nos. 7 and 8 in this category, were approved during 1947.Items 2 and 7, unmounted loader and power unit, respectively, under Loading and Conveying Equipment, item 2, rubber-mounted mining machine and item 8, distribution box, appear in Information Circular 7432. They are repeated to show that approvals of these four equipments were extended to cover an additional voltage rating which requires material change in design.Equipment listed in these circulars is approved by the Bureau of Mines only when found upon inspection and test to comply with minimum standards of safety as outlined in schedules prepared on the basis of many years of experience in dealing with safety problems of the coal-mining industry. The use of such equipment in mines known to be gassy, as well as in those that may become so, is earnestly recommended in the interests of safety. This circular is published so that the industry may be kept informed as to the many types of machines, devices, and lamps that are available for reducing explosion and other hazards incidental to coal mining. The present paper, with Information Circular 7432, gives the complete list of permissible mine equipment that is available under the various classifications."

May 1, 1948

By W. P. Yant

The widespread use of toluene in industry and the importance of air analysis in industrial-hygiene surveys have created a need for a simple and accurate method for determining toluene vapor in air. Most of the methods used to determine small quantities of toluene in liquid or vapor form are based on the measurement of its physical properties. Methods based on fractional distillation, determination of specific gravity, use of the interferometer, use of the spectrograph, and sorption on solid sorbents with subsequent determination of gain in weight have been employed. Distillation and specific-gravity methods are not applicable to the small quantities of toluene found in the air, and use of the interferometer, spectrograph, and sorption methods either are not specific for toluene in the presence of other volatile substances or require expensive equipment.

Jan 1, 1936

By W. P. Yant

The widespread use of toluene in industry and the importance of air analysis in industrial-hygiene surveys have created a need for a simple and accurate method for determining toluene vapor in air. Most of the methods used to determine small quantities of toluene in liquid or vapor form are based on the measurement of its physical properties. Methods based on fractional distillation, determination of specific gravity, use of the interferometer, use of the spectrograph, and sorption on solid sorbents with subsequent determination of gain in weight have been employed. Distillation and specific-gravity methods are not applicable to the small quantities of toluene found in the air, and use of the interferometer, spectrograph, and sorption methods either are not specific for toluene in the presence of other volatile substances or require expensive equipment.

Jan 1, 1936

By Robert L. Lagace

This final report documents the work done by Arthur D. Little, Inc. (ADL) on behalf of the U.S. Bureau of Mines, Pittsburgh Mining and Safety Research Center (PMSRC) , on Contract H0122026 (which began in August of 1971) . Under this contract ADL provided technical assistance to the Bureau on a task basis on virtually all aspects of the Bureau's programs related to present and planned emergency and operational communications and miner location systems for underground coal mines. The work consisted of in- dependent investigations, analyses, experiments, breadboard and prototype hardware development, workshops and technology transfer seminars on mine communications, and on-going evaluations and guidance related to the Bureau's contracted programs on electromagnetic noise, mine communications systems, and trapped miner location. This final report documents the work in two volumes, Volume I, "Emergency and Operational Mine Communications," and Volume II, "seismic Detection and, Location of Isolated Miners." The Tables of Contents of both Volumes are included in each Volume.

Jan 1, 1974

By William J. Campbell

The Federal Bureau of Mines provided five test materials--amosite, short-and long-fiber chrysotile, crocidolite, and nonfibrous tremolite--to the National Institute of Environmental Health Sciences (NIEHS) for studies on the biological effects of orally ingested asbestos-related materials. An inter-agency agreement between the Bureau and NIEHS made possible this program to characterize these test materials. The Bureau in turn received support through contracts with the Ontario Research Foundation for the milling of amosite and crocidolite, and with the University of Maryland for microscopic measurements. The five test materials, which were supplied in quantities of 960 to 1,200 pounds each, were characterized by chemical-instrumental analysis for elemental composition, surface area, density, X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, mineralogy, and particle size analyses. Particle size distributions were emphasized because of the current theories relating adverse biological effects to length-width characteristics of durable elongated particles.

Jan 1, 1980

By D. S. Colby, E. M. SEELEY

The total production capacity of the natural-gasoline industry increased to 27,212,000 gallons (647,905 barrels) daily on January 1, 1950, from 21,322,000 gallons (507,670 barrels) daily on January 1, 1948. The rate of growth during these 2 years averaged 13 percent per year, compared with 9 percent per year from 1946 to 1948 and 6 percent from 1944 to 1946. The total number of operable plants on January 1, 1950, was 554, 5 more than at the beginning of 1948. The number of absorption plants increased by 12, the number of cycling plants by 7, and the number of combination plants by 4. The number of compression plants and charcoal plants continued to decrease. Absorption plants accounted for 67 percent of the total capacity on January 1, 1950, compared with 62 percent 2 years previous. Eighty-two per- cent of the expansion in these 2 years was in absorption-plant capacity. Cycle plants accounted for 24 percent of the total industry capacity at the beginning of 1950, compared with 27 percent on January 1, 1948. The average daily capacity of absorption plants increased from 38,400 gallons at the beginning of 1948 to 50,600 gallons at the beginning of 1950. During the same period, the average daily capacity of cycle plants decreased from 150,200 gallons to 144,100 gallons. Texas showed the largest gain in number of plants 13 absorption, 4 compression, and 4 cycling plants. The State accounted for 67 percent of the gain in capacity and on January 1, 1950 had 50 percent total national capacity. Louisiana followed with 7 additional plants. Pennsylvania reported 14 and West Virginia reported 13 fewer plants than in 1948. Most of these reductions were in the number of compression plants.

Jul 1, 1950

By Maria I. De Rosa

The U.S. Bureau of Mines performed experiments to determine if the primary gas toxicities evolved during the early (-300° C) and later (>400° C) combustion stages of mine conveyor belts could be predicted by a smoke particle characteristic. The experiments were conducted in an approximately 20-L furnace at set furnace temperatures of 150°, 250°, and 1,000° C, with a furnace airflow of 10 L/min. The variables studied, as a function of time, included hydrogen chloride and carbon monoxide concentrations, the average smoke particle diameter (d8 and number concentration (no), and the product of the average smoke particle diameter and concentration (dgn0) Other variables included the sample and furnace temperatures and the sample mass weight loss. Results show that the inverse of the smoke particle diameter-concentration product (ldgn0), correlates directly with the hydrogen chloride and carbon monoxide toxicities released in large quantities during the early and later stages of combustion.

Jan 1, 1989

By S. C. Schaefer

Thermodynamic properties of indium oxide (In203) have been studied with a high-temperature galvanic cell employing stabilized zirconia electrolytes. In the temperature range 790° to 1,230° K the free-energy change for the cell reaction 21n(1) + 3Cu20(c) = In203(c) + 6Cu(c) together with the standard free energy of formation of cuprous oxide gives the standard free energy of formation of indium oxide from the elements as ?Gf° = -218.78 + 75.34 X 10-3T ±0.7 kcal/mole. A third-law analysis yields the standard enthalpy of formation: ?Hf°298.15 = -221.5 kcal/mole.

Jan 1, 1971

By J. A. Cavallaro

To determine whether magnetite consumption could be reduced and salable coal production increased by using froth flotation units in series with magnetic separators, the Bureau of Mines conducted laboratory froth flotation tests on primary magnetic separator effluents obtained from three coal preparation plants. Tests were performed in a standard 500-gram-capacity laboratory batch flotation cell. Oleic acid and methylisobutyl carbinol were used as the collector and frother, respectively. Magnetite recovery was comparable to that expected from secondary magnetic separation, and salable float coal recoveries of 0,8 to 7.6 tons per hour were obtainable. The economics of the proposed technique appear to be sound.

Jan 1, 1966

By F. G. Scott

This document is a proposed program plan for mining environmental research to be conducted by the U.S. Bureau of Mines in support of industrial oil shale mining and processing. This program plan is one of three research alternatives being considered by the Bureau, each based on a different level of anticipated funding. This report documents the high funding level program plan.

Jan 1, 1980

By Christopher Van Dyke, Edward L. Petsonk, Knox Van Dyke, Vincent Castranova, Ji-Hee Kang, William Pailes

"INTRODUCTIONPlatelet-activating factor (P AF) has been shown to mediate a broad range of biologic activities (1). Chemical analysis has shown that PAF is a glycerophospholipid with a choline polar head group, an ester-linked acyl chain at the second carbon of the glycerol backbone, and an ether linkage at the first carbon. The alkyl group attached to the first carbon can exist in a variety of chain lengths, with the C16 and C18 forms predominant in humans. The structure of P AF has been identified as 1-0-alkyl-2-acetyl-sn-glycerol-3-phosphorylcholine (2,3).PAF can be released from a variety of cell types, such as basophils, neutrophils, and alveolar macrophages ( 4-6). Stimuli for the release of P AF include calcium ionophore, phorbol esters, chemotactic agents, and zymosan. In addition, endotoxin has been shown to be a potent stimulant of P AF release from alveolar macrophages (7).P AF has been shown to have a number of pulmonary effects. It has been associated with asthma since it can cause contraction of pulmonary tissue (8) and leukotriene secretion from leukocytes (9) and induce airway constriction when inhaled by humans (10). In addition, PAF is a potent chemoattractant and can cause migration ofneutrophils into the airspaces of the lungs (11,12). Endotoxin is a lipopolysaccharide-protein complex derived from the cell walls of gram-negative bacteria. I.PS is the lipopolysaccharide portion of endotoxin. LPS contains four covalently joined subunits: lipid A, 3-deoxyoctonate, a core polysaccharide moiety, and an 0-specific antigenic polysaccharide side chain. Rough LPS contains no 0-antigen side chain. The liP.id A portion of LPS has been associated with most of the biolQgic effects of endotoxin (13). This lipid A subunit consists of a D-glucosamine disaccharide backbone substituted with four fatty acid side chains. Endotoxin is found in a wide variety of occupational settings associated with organic dusts derived from plants or animals, such as cotton, cereal grains, silage, rice, and poultry (14-18). In addition, airborne endotoxin has been found in sewage treatment plants, composting plants, offices with contaminated humidifiers, and showers or saunas (19-22)."

Jan 1, 1990

By David C. Oyler

Methane-drainage holes must be completely filled by grout before mining to prevent the emission of large quantities of gas during mine-through, which would constitute an explosion hazard. In November 1980, seven horizontal holes at the multipurpose borehole, a small-diameter shaft drilled as a Bureau of Mines coalbed methane-drainage installation on the property of the Federal No. 2 Mine, Monongalia County, WV, were plugged using a sodium silicate gel grout. This report de- scribes the grout mix and the use of the grout at the multipurpose borehole, and discusses the results observed upon mine-through of the holes in early 1981. Cost data for the sodium silicate grout are also presented.

Jan 1, 1984

By Charles Vaught

This is the second in a series of four articles that discuss underground firefighting preparedness. As with the first article in the May-June issue, it is based on interviews with 214 miners conducted at 7 underground mines (?A? through ?G?) by researchers of the National Institute for Occupational Safety and Health?s (NIOSH) Pittsburgh Research Center [Vaught et al. 1996].In the first article, the authors presented an overview of the study conducted by NIOSH on mine fire response preparedness and provided a general perspective on underground mine fires. In this article, we will describe miners? preparedness to evacuate a fire and their experience with incipient fires.

Jan 1, 1997

By W. L. Dare

The Federal Bureau of Mines is publishing a series of studies on the methods and costs of mining uranium on the Colorado Plateau. This report describes the longwall-mining methods and techniques used at the Radon mine, Big Indian district, San Juan County, Utah. The tabular Radon ore body lies on the southwest flank of the Lisbon Valley anticline, strikes N. 10° W., dips 7° SW., and has an average thickness of 4-1/2 to 5 ft. The mine is developed by a three-compartment vertical shaft, a haulage level driven beneath the ore, and a system of drifts driven within and parallel to the strike of the ore.

Jan 1, 1961

By D. R. Tesarik, F. M. Jones, J. B. Seymour, L. A. Martin, T. J. Williams

Determining backfill stress is an important part of evaluating mine safety, whether personnel are working in proximity to backfill or in other areas of the mine where backfill is an integral part of regional support. To assist in determining stress in backfill more accurately, researchers from the Spokane Research Laboratory of the National Institute for Occupational Safety and Health, Placer Dome, Inc. (Turquoise Ridge Mine), Peabody Energy Co. (Foidel Creek Mine), and Hecla Mining Co. (Lucky Friday Mine) used temperature readings recorded by thermistors to correct for the influence of temperature on stress data. These thermistors were positioned in the stems of earth pressure cells installed in backfill. Corrections were then calculated and compared using four different methods: polynomial equations fit to temperature-versus-stress plots before the pressure cells were loaded by overburden, a factor provided by the manufacturer, a theoretically derived factor, and a linear correction factor based on information collected during periods when no mining was taking place. To evaluate the accuracy of these methods, corrected stresses were calculated using each method and results compared to cumulative stresses caused by blasting at one of the mines. Results indicated that only a small percentage of the temperature effect on stress was corrected using the factor from the manufacturer because that factor accounted for only the pressure transducer and not the entire instrument body. Stresses adjusted with a linear correction factor based on information collected during periods when no mining was taking place were the most accurate. Stresses recorded at two other mines were corrected using the theoretical method and the polynomial equations method; the two methods produced similar results. For some time intervals, the results were identical.

Jan 4, 2006

By John E. Pahlman

The Bureau of Mines investigated the feasibility of removing heavy metals from mineral-process waste streams by precipitation with lignochemicals and humic acids. Lignochemicals are by products from the paper industry, while humic acids are obtained by caustic treatment of peat, subbituminous coal, and lignite. These high-molecular-weight organic materials have many functional groups, which can coordinate and form innercomplex salts with heavy metals that are crystalline precipitates. Filtering of a humic-acid-or lignochemical-treated solution or waste stream containing these precipitates removes the heavy metal sequstrates. Tests were conducted with two lignochemical samples, three humic acid samples, lime (CaO), and sodium hydroxide (NaOH) in which increasing amounts of these additives were reacted with 50 mL of solution containing Fe3+ , Al3+, Cr3+, Pb2+, Cu2+, Cd2+, Zn2+, Co2+, Ni2+, Mn2+, and Hg1+. At the appropriate pH, greater than 90-and 99-pct removal was achieved for these 11 heavy metal ions from the 10-and lOO-ppm solutions, respectively, using lignochemicals and humic acids. Removal efficienC)' with these organic materials is better than that with CaO, especially for the more toxic ions, Hg1+, Cd2+, and Pb2+. Unlike the precipitates formed with NaOH or CaO, those with lignochemicals and humic acids are compact and noncolloidal. The volume of their sludge is sharply lower than that of the finely dispersed lime or soda precipitates; thus, their removal in settling tanks or by simple filtration is enhanced.

Jan 1, 1988

By R. P. Adams, R. A. Beall

The Bureau of Mines developed a method to melt and cast specimens of hafnium- carbon alloy and studied their properties . A rotating - ladle vacuum or inert atmosphere arc furnace was designed , special electrodes and molds were developed , and operating procedures were worked out for casting small shapes . The cast specimens were evaluated according to their carbon content for melting point , density , microhardness , electrical resistivity , and oxidation resistance . Lattice dimensions were determined , and metallographic specimens were prepared . Photomicrographs were taken of specimens containing 2.72 , 5.50 , 6.47 , 9.97 , 12.8 , and 15.7 weight - percent carbon , and their grain structures were compared .

Jan 1, 1963

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Jan 1, 2012

By F. R. Cattoir

This report presents the results of preliminary studies for the evaluation of some fused-salt electrolytes for refining tungsten metal, and describes the equipment used. Some impurities could be eliminated with electrolytes composed of sodium chloride, sodium iodide, or sodium tetraborate in combination with tungstic oxide or sodium tungstate. Electrolytes composed entirely of chlorides were unusable because of the volatility of tungsten chloride. Refining 96-to 98-percent tungsten to produce a commercial grade was more successful than further refining of 99.9-percent tungsten. No electrolyte tested yielded a product pure in all respects. Electrolyte temperatures of about 900° C were necessary to maintain a good dissolution rate at the anode and acceptable cell operation. Cathode current densities at the beginning of a deposition cycle were limited to approximately 1 ampere per square inch. Higher current densities resulted in a finely divided product that frequently failed to adhere to the cathode. The most conspicuous impurities in the tungsten produced were carbon, iron, and molybdenum; the former two came from the iron cell and the graphite cell liner. Electrolytes com-posed of tungstic oxide or sodium tungstate in sodium iodide, or 2Na, 0.B203, were capable of producing tungsten carbide.

Jan 1, 1963