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By J. L. Stauffer, L. J. Gaydos, L. M. Demers, D. C. Kuhn

"Eicosanoids and cytokines produced by alveolar macrophages (AM) are key mediators of pulmonary inflammation and fibrosis. In order to determine if eicosanoid production and cytokine production are altered in AM obtained from coal miners, we compared production of prostaglandin E2 (PCE2), thromboxane A2 (TXA2), leukotriene B4 (LTB4), interleukin-1 beta (IL-1B ), and tumor necrosis factor alpha (TNfa.) by cultured AM from normal human subjects and coal miners. The recovery of AM from miners' lungs by bronchoalveolar lavage was significantly greater than that from control subjects. Mean eicosanoid and cytokine production by AM from active miners was also increased compared to AM from control subjects, but this increase was not statistically significant. AM from control subjects produced significantly more TXA2 and TNFa. when exposed to lipopolysaccharide than did AM from miners. The cyclooxygenase inhibitor suprofen reduced PGE1 and TXA1 production and TNF0t. release but had no effect on LTB4 production or IL-1B release by miners' AM. The lipoxygenase inhibitor nordihydroguaiaretic acid attenuated TNFa release, as well as that of LTB4, but had no effect on IL-1B release. Inhibition of thromboxane synthase by UK 38,485 also reduced TNFa release by active miners ' AM but had no effect on PGE1, LTB, production, or IL-1 f3 release. The results of these studies suggest that occupational inhalation of coal dust may increase total lung eicosanoid and cytokine levels and reduce the reactivity of AM to bacterial endotoxin. Furthermore, coal dust-induced changes in both eicosanoid and cytokine release may be subject to pharmacological modulation.The alveolar macrophage (AM) is a primary defensive cell in the lung and is one of the first cell types to encounter inhaled mineral dust. The response of the AM to invading foreign material is designed to enhance the defensive capacity of the lung. However, in the case of occupational inhalation of mineral dust particles, this response may be inappropriate, resulting not in the defense of the lung but in chronic inflammation and fibrosis (Rom et al., 1987; Takemura et al., 1989). The reaction of the AM to chronic mineral dust exposure may involve the exaggerated release of paracrine mediators of lung function, including eicosanoids (oxygenated derivatives of arachidonic acid) and peptides, including cytokines and growth factors (Sibille & Reynolds, 1990). Eicosanoids are involved in bronchial and vascular smooth muscle reactivity, vascular permeability, fibroblast growth, and the recruitment of additional immune cells to the alveolar space (Barnard et al., 1992; Elias et al., 1985; Scott et al., 1982). AM-derived cytokines such as interleukin-1 beta (IL-1 B) and tumor necrosis factor alpha (TN Fa) have a variety of biological activities including the regulation of fibroblast growth and proliferation (Becker et al., 1989; Libby et al., 1989; Schmidt et al., 1984). Interestingly, in vitro studies with macrophages suggest that the production of cytokines may be linked to eicosanoid production, in particular that prostaglandin E2 (PGE2) may down-regulate IL-1 f3 and TN Foe production by the AM (Bonta et al., 1989; Kunkel et al., 1986; Monick et al., 1987)."

Dec 1, 1996

By W. M. Deaton

The Keyes Helium Plant of the Federal Bureau of Mines was constructed under an expedited schedule, to supply the urgent and growing demand for helium in atomic energy, missiles, aerology, space exploration, shielded-arc welding, and low-temperature research. Construction began in December 1958 and ended in August 1959. The plant, near Keyes, Okla., processes 2 percent helium-bearing natural gas from the Keyes gasfield. In 1960 the plant produced and shipped 263 million cubic feet of helium (equivalent to an annual rate of 290 million cubic feet). Production cost was $9.11 a thousand cubic feet of helium. A low-temperature process involving two steps is used; the first separates a crude-helium product from the natural gas at about -250° F. and 225 pounds per square inch gage (p.s.i.g.); and the second purifies the crude helium to a high-purity product (Grade-A helium, 99.995 percent helium) at about -320° F. and 2,750 p.s.i.g.

Jan 1, 1961

By Ludwig Schmidt

"IntroductionThe evaporation losses of gasoline in the refinery, can be reduced by proper methods of refinery construction and operation. When gasoline evaporates slowly, as when stored in tanks that are not vapor tight, the most volatile part evaporates first, so that the remaining liquid in not only less in volume, but is also lower in quality. In some,evaporation changes the characteristics of the product so much that it must be reblended to meet trade specifications.Refiners are, therefore, greatly interested in the various appliances and methods used to reduce these losses. In the past this interest has been directed largely to storage tanks, probably because evaporation from tanks is more readily observed than losses during other refinery operations. As tests by the Bureau of Mines on evaporation of gasoline from small storage tanks had indicated that the losses during the various stages of refining might be equal to or greater than those of standing storage, a survey was during the spring and early summer months of 1924 in a large number of refineries in the Mid-Continent field. In order to enable the refiner to select the results of those tests that conform most nearly to the conditions that he has to meet, tests were conducted at various stages of refining, as follows: (1) Randown tanks, (2) (agitators), (3) filling tank cars, (4) storage of refined products, and (3) miscellaneous handling. The results are presented in this paper."

Nov 1, 1925

By Alfred E. Schwaneke

A new high-temperature soft soldering system has been developed by the Bureau of Mines for use on copper, copper alloys, and low-carbon steel; the method is applicable to automobile radiators and home appliances. The system uses a unique sacrificial metal coating method to promote spontaneous wetting and spreading of zinc and zinc alloy solder: on metallic substrates. The 10-5 to 10-6 cm thick, electroplated or sputtered, sacrificial nickel coating is absorbed by the molten filler alloy during soldering and produces a direct solder-substrate metallic bond. Preliminary measurements on butt joints with copper members give tensile strengths up to 22,000 psi at room temperature using 95 Zn-5 Al alloy as solder. Spontaneous wetting, spreading, and capillary penetration are extremely rapid and produce joints as easily as 50-50 tin-lead solders. Recrystallization or annealing of the wrought copper joint members is negligible at the soldering temperatures of 450° to 490° C and lower. A list of fluxes and solder alloys is included in the report.

Jan 1, 1970

By Jalna R. Zatko

Coal-clay waste slurries were dewatered in laboratory-and small-scale continuous tests by the Bureau of Mines using polyethylene oxide (PEO) as a flocculant. Dewatering from a nominal 7-wt-pct solids to over 50-wt-pct solids was accomplished using 0.5 lb of PEO per ton of feed in small-scale continuous tests. Parameters such as pH, initial solids content, and PEO concentrations were investigated. Water recovered from dewatering was reused as dilutant for PEO solutions.

Jan 1, 1982

By W. L. Dare

This information circular is one of a series published by the Federal Bureau of Mines in which the methods and costs of producing uranium ore on the Colorado Plateau are discussed. This report describes the three largest company-operated uranium mines of Climax Uranium Co. - the G-1, the Mineral Joe, and the Frank No. 1. Climax Uranium Co., a subsidiary of American Metal Climax, Inc., was [corporated] May 11, 1950, just 2 years after establishment of the domestic uranium program by the Atomic Energy Commission. Twenty-five years earlier Arthur H. Bunker, now chairman of the board, American Metal Climax, Inc., organized and operated the U. S. Vanadium Co. at Rifle, Colo.3/ Soon after Climax Uranium Co. was organized, it entered into a contract with the Federal Government to build a uranium-vanadium processing mill in Grand Junction, Colo. Under the contract Climax leased from the Federal Government certain uranium-bearing lands that had been withdrawn from public entry in 1948. From Minerals, Engineering Co. on June 12, 1950, Climax acquired other uranium-vanadium properties on Calamity, Outlaw, and Monogram Mesas in Colorado and on Polar Mesa and in the Yellow Cat area of Utah. To house the milling equipment, Climax leased the old Grand Junction sugarmill building of the Holly Sugar Co. Milling facilities, based on a then new process developed for treating both uranium and vanadium, were completed, and the plant went into production in 1951.

Jan 1, 1959

By P. T. Brooks

A process for extracting 69 percent of the vanadium from weathered Nevada dolomitic shale containing about 1 percent V205 was developed on a laboratory scale by the Bureau of Mines. The process essentially is comprised of salt roasting, leaching with dilute sulfuric acid, solvent extraction, and precipitation of vanadium as ammonium metavanadate. Carbonaceous unweathered shale was less amenable to treatment. A preliminary cost estimate for mining and processing 1,500 tons per day of weathered shale indicated a production cost of about 1 dollar per lb of V205. Considering recent sales at nearly $1. 75 per lb of contained V205, larger scale testing to obtain more definitive process design and evaluation data may be warranted.

Jan 1, 1974

By Wm. W. Odell

For a number of years there has been a very appreciable annual,, increase in the production and recovery of natural gas and natural-gas gasoline2 in the United States the latter product being used largely for blending with gasoline from petroleum in the production of motor fuel. On account of the increased amount of oil cracking in the production of gasoline and the accompanying increased percentage of low-boiling constituents in the resulting product, the specifications for the natural gasoline suitable for blending have been altered, that is, the amounts of propane and butane which it can contain have been limited. The result has been that large quantities of the latter materials are wasted because there has been no ready market for thorn in large quantities. Because of this wasteage and because it is probable that large quantities of there and similar materials will be produced in the near future us a result of the more general use of oil cracking processes, a study was made by the Bureau of Mines, under a cooperative agreement with the assistance of the Phillips Petroleum Company, of the suitability of these materials alone or in mixtures for use as gas enricher in the carburetion of water gas for city distribution. This investigation included: (a) A study of the properties of the low boiling members of the paraffin series including pentane with particular reference to their utilization as gases.

Jan 1, 1927

By Robinson Newcomb

Gypsum is a form of hydrated calcium sulfate (CaS04.2H20) which is widely distributed over the earth's surface. The two varieties worked commercially are rock gypsum and incite. Rock gypsum, the variety commonly mined for commercial purposes, is a relatively soft mineral having a specific gravity of about 2.3 and weighing about 150 pounds per cubic foot. The chief producing States are New York, Michigan, and Iowa. Before being used the crude gypsum is ground and generally calcined. The predominant use of gypsum is for building purposes (the manufacture of plaster), for which calcined gypsum is required. Gypsum is also used as a retarder in Portland cement, as fertilizer, and for other purposes. GYPSUM MINING Crude gypsum is mined by two methods - underground and open-pit. Although the use of the former method predominates, open-pit mining increased in relative importance during the early twenties and contributed about two-fifths of the output during the period 1925-38.

Jan 1, 1940

By Louis A. Panek

Tests of mine-roof models in a centrifuge show that the suspension effect due to bolting a horizontally bedded mine roof with frictionless surfaces of contact between beds depends principally on the number of bolted beds and their relative flexural rigidities, provided that sufficient bolt tension is exerted to prevent strata separations at the bolt locations. Strata separations tend to occur in the unbolted roof mainly because the beds have unequal thicknesses. "Suspension effect" refers to the transfer of part of the weight of weaker or thinner beds to the flexurally more rigid beds by roof bolts or by any other means. The factors investigated were number of beds in the bolted unit, bed thickness, modulus of elasticity of beds, length of bolts, spacing of bolts across and along the opening, bolt load, and intensity of roof load. The general principles of behavior of the bolted roof beds are explained by an approximate theory. Model test data are used to validate the theory and to obtain an expression for the "suspension efficiency". As the suspension effect actually observed in the models is smaller than that predicted by the approximate theory, the suspension efficiency in general is less than unity. Mathematical expressions are obtained for (1) the change in roof bending stress due to the suspension effect, which is needed for design of a roof-bolting system, (2) the change of roof deflection due to the suspension effect, which may be useful for evaluating the effectiveness of a roof-bolting system, and (3) the bolt load or pre-load that is required to achieve the desired reinforcing effect.

Jan 1, 1962

By H. D. Jacobs

A process for recovering both iron and manganese from four manganiferous ores of the Cuyuna Range was evaluated. It comprised: (1) Low-temperature gaseous reduction to convert nonmagnetic iron minerals to magnetite and manganic minerals to manganous oxide, (2) acid leaching to extract manganese, and (3) magnetic separation to reclaim iron from the leach residue. Iron recoveries from the magnetic products ranged from 70 percent to 90 percent; manganese recoveries from leach filtrates ranged from 75 percent to 95 percent. Two ores, from the Hillcrest and South Alstead properties, yielded magnetic products considered adequate for use as blast furnace feed. Although good yields of manganese were attained on all ores, appreciable iron accompanied the manganese into solution. Previous work, however, has shown that this iron can be precipitated almost quantitatively under autoclave oxygen pressure with very little loss of manganese.

Jan 1, 1970

By J. B. Zink, M. J. Peterson

A semiquantitative spectrochemical method was developed and applied to the analysis of ash of U.S. coals . A low- temperature ashing procedure was used to minimize the loss of volatile elements . The analytical procedure provides for the estimation of 68 elements including major , minor , and trace constituents . Standards for the trace elements were prepared in a synthetic base mixture that approximates the average composition of U.S. coal ashes . Excitation was achieved with a d- c arc , spectra were recorded photographically , and interpretation was made by visual comparison of spectra of unknowns with spectra of graded standards series . Thirty- six trace elements were found in the analysis of 900 samples . Details of the procedure are presented , including sample and standards preparation , excitation and exposure conditions , spectral lines used , and approximate limits of detectability .

Jan 1, 1964

By H. R. Appell

The Bureau of Mines studied the conversion of a variety of cellulosic wastes, for example, sawdust, bovine manure, sewage sludge, urban refuse (free of metal and ceramics), etc., to heavy oils. The objective of the investigation was to determine the scope of the reaction and elucidate the chemistry involved. The reactions took place in the presence of synthesis gas and water or carbon monoxide and water under conditions of elevated temperatures and pressures. Waste conversions above 90 pct, often near 99 pct, with oil yields in the range of 40 to 60 pct, were obtained in the temperature range of 250° to 425° C and pressure range of 1,500 to 4,000 psig. Because mild conditions were sought, most of the experiments were conducted at temperatures of 250° to 350° C and pressures of 1,500 to 3,000 psig. In general, lower viscosity products were obtained at higher reaction temperatures. Conversions and oil yields were significantly increased by operating in the presence of a high-boiling oil; either anthracene oil or oil recycled from the process was satisfactory. Synthesis gas containing 50 pct carbon monoxide gave satisfactory results as a replacement for carbon monoxide. Cobalt molybdate on alumina catalyst, used with sodium carbonate, gave a product of lower viscosity and lower oxygen content than sodium carbonate used as the sole catalyst. The waste-to-oil process has been successfully investigated in continuous flow equipment as well as in batch autoclaves.

Jan 1, 1975

By K. C. Dean

The combination of flotation and chemical processing methods presented in this report of the Bureau of Mines enabled treatment of typical low-grade ferberite ores from the Boulder County, Colo. area, to produce specification-grade synthetic scheelite. The overall recovery from ore to synthetic scheelite was 87 percent, based on a flotation recovery of 93 percent and a similar recovery in chemical processing. Preliminary mineral dressing studies revealed that the physical and mineralogical nature of typical ferberite ores precluded high recovery of tungsten in plus 60-percent-W03-grade products by these methods. Therefore, the flotation research was focused on attaining plus 90-percent recovery in a concentrate containing 10 percent W03. Detailed studies were made (1) to establish optimum grinding conditions for obtaining adequate mineral liberation, (2) to develop collecting and modifying reagent combinations that would enable controllable selective flotation, and (3) to define the influence of different pulp solids, temperature, pH, and time for conditioning and for the rougher and cleaner flotation stages.

Jan 1, 1961

By R. A. Isberg, D. A. Parrish, H. Kramer

This report describes the design and implementation of UHF radio and closed-circuit television systems in the Black River room and pillar limestone mine near Butler, Pendleton County, Kentucky. Prior to designing the radio system, measurements of signal attenuation on 812 and 466 mHz were made in the slope tunnel and in the straight and level crosscuts in the mine. Two distributed antenna systems fed by two sets of base stations provide approximately 75% coverage of the mine. Passive reflectors are used for extending signals into intersecting crosscuts and two-way signal boosters will be used to extend signals to the perimeter and obstructed areas of the mine. Fourteen mine vehicles were equipped with mobile radios equipped with digital identification, alarm and status encoders. Fifteen portable transceivers also were used. Six closed-circuit television cameras provide surveillance of critical transfer points of the belt conveyor system, and the loading dock at the base of the slope and an ash disposal area in the mine. Two-way radio communication and closed-circuit television have saved considerable man. hours, increased production, reduced maintenance costs and enhanced safety. Innovative developments were the use of passive reflectors and two-way signal boosters for extending signals into intersecting crosscuts, development of lightweight signal margin measuring equipment, modifications of mobile digital encoders to automatically send status information from mine vehicles such as numbers of loads of ore delivered, hot engine, etc., and the use of CATV technology for multiplexing audio, digital and video signals onto coaxial cables from the surface to the mine.

Jan 3, 1981

By W. S. Sanner

This report describes the commercial application of the launder screen in anthracite-industry fine-coal cleaning operations. No new device, the launder screen has been used since the early part of the present century to size, screen, classify, and deslime the fine-anthracite sizes (Buckwheat Nos. 1 through 5) recovered by "river-coal" men dredging along streams draining the anthracite fields. The launder screen is stationary, has no moving parts, requires ample water for operation, and can be constructed economically on the job. Essentially, it consists of a wooden trough with baffles placed through its width to form a well system. The wells are covered by fine-mesh woven-wire screening. Each well is tapped with a number of orifices, and the hydraulic suction head developed in this manner removes high-gravity fines and slimes through the screening as underflow to waste. Material retained on the screen surface discharges as overflow product.

Jan 1, 1954

By W. W. Adams, T. D. Lawrence

"Despite the manpower shortage and other difficulties of operation in war time, the National Safety Competition of 1943 for the promotion of safety in the mineral industries of the United States was notable for having a larger enrollment of mines and quarries than in any other year except 1941 and 1942 since the yearly safety contests were inaugurated in 1925. The competition was also notable for having a larger number of man-hours represented by the competing companies than in any previous contest except that of 1942. The ratio of accidents and days of disability resulting from accidents to the number of man-hours of work performed was more favorable than in 1942; the accident-frequency rate was lower and therefore better than in 13 of the 19 years during which the annual safety competitions have been conducted, and the accident-severity rate was better than in 16 of the 19 years.The National Safety Competition is a yearly safety contest conducted by the Bureau of Mines, United States Department of the Interior. Companies that win first place in their respective group in the contest are awarded a bronze trophy, ""The Sentinels of Safety,"" which is provided by THE EXPLOSIVES ENGINEER magazine. Competing companies are segregated into six groups: Underground bituminous-coal mines, underground anthracite mines (in Pennsylvania), underground metal mines, underground nonmetallic-mineral mines, open-cut mines (without regard to kind of mineral produced), and open quarries (without regard to kind of stone produced). The bronze trophies are retained by the six winning companies for 1 year and are then transferred to the winners of the succeeding year's contest. On the pedestal of each trophy is engraved the names of the winners of the trophy. With the award of the trophies for 1943, therefore, the pedestal of each trophy bears the names of 19 winners."

Aug 1, 1944

By Frank J. Wiebelt

In its efforts to maintain production of tungsten during the recent war period, the Bureau of Mines explored certain parts of the properties of the Atolia Mining Co. in San Bernardino County, Calif., by diamond drilling. Owing to past production record and other available data, the area was considered attractive for possible development of new ore bodies. Scheelite occurs in narrow veins ranging in width from a fraction of an inch to several feet. The veins are in quartz monzonite in a zone 2 miles long and 500 feet wide. Production from the district was reported to have been over 1,000,000 units of W03. Twelve diamond-drill holes, totaling 5,056 feet, were drilled by the Bureau of Mines in the vicinity of the Papoose, Papoose No. 5, Amity, and Union mines, the tailings pond, and the "Old Spud Patch." The work began in August 1943 and was completed in June 1944. This publication briefly describes the history and deposits of the district and gives full details of the work performed by the Bureau.

Jan 1, 1950

By C. O. Ruud, R. E. Siemens, D. Chandra

The mineralogical constitution of a lateritic ore dictates the type of metallurgical process that can be used to extract valuable metals such as nickel and cobalt . To provide needed mineralogical information on the interrelationships of the metals contained in domestic laterites , the Bureau of Mines awarded a grant to Denver Research Institute to study the transition - type , low - grade laterites found in northern California and southern Oregon . For comparison , limonitic - type laterites from New Caledonia and the Philippines were also studied . X-ray diffraction , electron microscopy , electron beam analysis , and conventional petrography were used to determine the mineralogical associations of nickel and cobalt in the laterites . Results showed that for both laterite types studied most of the nickel and minor amounts of cobalt are associated with the mineral geothite ( FeO ( OH ) ) . Most of the cobalt and minor amounts of nickel are associated with a mixed manganese oxide (wad ) mineral .

Jan 1, 1983

By Walter Kawa

Bureau of Mines research on the hydrogenation of coal has been concerned with developing processes that could be used to supplement the Nation's petroleum and natural gas resources. Motor fuel was produced in a subsidized coal hydrogenation industry in Europe prior to 1945, but the process used is still not economical and other methods of producing liquid and gaseous fuels from coal are being investigated. As an aid to the planning of coal hydrogenation research, a literature survey was made of processes or methods of hydrogenating coal that differ from the subsidized or conventional process. This report contains a bibliography of unconventional methods of hydrogenating coal and a brief discussion of the economics of the conventional method. A general discussion of unconventional methods is included, and the advantages and disadvantages are pointed out where possible. The survey supplements a previous Bureau of Mines survey3 and a comprehensive review published in 1930.4

Jan 1, 1964