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By Hanns J. Billmayer

This report, which covers the period from June 15, 1974 to May 30, 1975, describes the work performed in compliance with the requirements of Contract No. H0242065 and modifications 1, 2, and 3 thereto. The purpose of the original contract was to equip the second shuttle car in the Jewell Ridge No. 12 mine, section 6R, with a refined design canopy and seats. In addition, several refinements and improvements were to be designed and installed at the same location on the cutter and the loader. However, during October 1974 in response to a request from the Technical Project Officer, the contract was modified to eliminate all of the cutter and loader tasks and substitute the design, fabrication, and installation of an improved canopy on the no. 2 roof drill in the above mentioned section of the Jewell Ridge No. 12 mine.

Jan 1, 1975

By Philip C. Tully

These modifications to the Redlich-Kwong equations for pure hydrogen and neon were developed after an unsuccessful attempt to generalize a modification technique previously developed for helium. New coefficients of the B terms were developed by minimizing the residuals. No changes were made in the coefficients of the A terms. For normal hydrogen, B was changed to [0.08063Tc PcT] for temperatures from 980 to 423° K and pressures up to 1,050 atm. The average deviation in Z was 0.36 percent with maximum deviations less than 1 percent for all but a few low-temperature points. For neon, B was changed to [PCT 0.1025T], for temperatures from 120° to 973° K and pressures up to 1,500 atm. The average deviation in Z was 0.34 percent with maximum deviations less than 1 percent for all but a few high-pressure and low-temperature points. Efforts to attain a lower temperature range to comparable accuracy with this type of modification were unsuccessful. In the range of applicability, these equations should be used with caution when calculating derived thermodynamic functions, such as the isobaric specific heat.

Jan 1, 1968

By C. M. Harrer

The location, features, qualities, and extent of iron occurrences and the associated resources--limestone and dolomite, bentonite, coal-lignite, petroleum and natural gas, power, and water--are evaluated. The results of pioneer beneficiation tests on South Dakota taconite are discussed. In addition, pertinent features of taconite development, cost factors, the Western and Central United States trade area and markets are reported. The State's production of iron ores until 1963 has been small and for purposes other than the manufacture of iron. This investigation disclosed the probability of large resources of taconite in Pennington and Lawrence Counties. The average iron content is 29 percent, and a 65-percent or better iron concentrate might be produced. Ample resources are available for mining and processing taconite. An investment of at least $26 million would be required for a plant capable of turning out 1 million tons of agglomerated iron concentrate per year. The feasibility of such an enterprise is indicated, but intensive investigation and research must be completed to justify such an investment,

Jan 1, 1966

By Robert M. Doerr

The purpose of the investigation was to determine the oxidation behavior of selected tungsten-cobalt alloys. Specimens of Wand W-Co containing 0.7, 1.7, 3.4, and 9.7 weight-percent Co were subjected to pure 02 at 1,000° and 1,100° K, and specimens of W-Co containing 29.8 weight-percent Co, at 1,100° K. Reaction kinetics were determined volumetrically. For specimens other than those containing 29.8 percent Co, the reactions proceeded at about a constant rate at either temperature, indicating the formation of a scale of constant protectivity; the reaction rates were essentially independent of the Co concentration. The scales on these alloy specimens consisted principally of WO3 and CoWO4. Specimens of a 29.8 weight-percent Co alloy, consisting primarily of the W6CO7 phase, oxidized with only slight deviations from the parabolic rate law at 1,100° K. The protective scale on these specimens consisted chiefly of Co3O4, CoW04, and W1 8°49; Co3O4 was outermost, and the W18O49 was adjacent to the alloy. The results suggest that the Co-rich outer scale inhibited the inward transport of 0 to an extent sufficient to greatly limit the amount of the nonprotective WO3 formed, so that protective W18O49 formed instead.

Jan 1, 1967

By A. B. Pederson, G. E. Bartlett

As a part of our study of how coal mine dusts injure the lung we have studied the effects of dusts and dust-exposed pulmonary alveolar macrophages (PAMs) on the growth of lung fibroblasts (LF). Fibroblasts were cultured near confluence in low-serum medium, either alone or in the presence of dusts, dusts plus PAMs, dust leachates or superriatants of dust-exposed PAM cultures. We report here provisional conclusions, based on initial observations. Rat LF were relatively unresponsive to direct effects of dusts, showing weak stimulation in only a few cultures, and there was no evidence that dust-exposed rat PAMs had released any growth-regulatory products. In contrast, guinea pig cells were more responsive to the dusts. The pattern of responses was quite complex. Three of the dusts stimulated LF directly (with no mediation by PAMs). Two dusts were essentially inert when added directly to fibroblast cultures, either with or without PAMs, but their leachates were active: 867 leachate was inhibitory and RF leachate was stimulatory. Dust 1361, either directly in the cultures or as an aqueous leachate, was stimulatory, and it activated cocultured PAMs to stimulate LF growth; however, supernatant products of 1361-stimulated PAMs were inhibitory. Direct exposure to 1192 stimulated LF, but its leachate was inert; cocultured PAMs exposed to 1192 had weak stimulatory effects, but supernatants of 1192-exposed PAMs were mildly inhibitory. MP3-3 had effects similar to 1192, except that the cocultured, dust-exposed PAMs had no effect on growth. We conclude 1) that guinea pig lung cells are more responsive to dusts than are rat lung cells, 2) that dusts can influence growth of LF by four kinds of interaction (by direct dust-cell interaction, by release of soluble dust components into the culture medium, by activating P AMs to exert direct cell-cell interactions, and by activating P AMs to release growth regulatory products into the culture medium), 3) that each kind of interaction may be neutral, inhibitory or stimulatory, depending on the dust tested, 4) that four of the dusts tested were neutral, inhibitory or stimulatory, depending on the assay (the fifth <lust was either neutral or stimulatory), and 5) that the effects of soluble mediators (leachates or products of activated PAMs) frequently did not correspond with the direct dust-cell or PAM-fibroblast effects. These results suggest that the nature of the dust-lung interaction at the level of cells and molecules is exceedingly complex. These observations need to be confirmed and extended to determine what characteristics of the dusts determine the nature of the cellular responses, and to determine which patterns of responses are detrimental and which are beneficial in the overall health of the dust-exposed lung.

Mar 1, 1989

By H. D. BAILEY, John W. Cole

This paper is one of a series on mining methods and costs published by the Bureau of Mines .. Because of the role, played by the Federal Government in the discovery of the ore body, a description of the exploratory operations of the Bureau of Mines, is included ...

Apr 1, 1948

By J. A. Kost

A survey of 80 coal producers was conducted to determine the extent and scope of respirable dust control research for underground coal mines and the current methods employed to control respirable dust. Results of the survey showed that proper face ventilation and an adequate water spray system are sufficient to comply with mandatory standards in room and pillar mining. Difficulties still exist with longwall equipment, auger miners and buring machines. In these cases, known dust control techniques are not sufficient to obtain compliance. Present state-of-the-art face ventilation and water systems were discussed in addition to the sampling program.

Jan 1, 1980

By C. M. Harrer

Reconnaissance investigations were made of 129 iron occurrences in Arizona to determine their extent, attitude, and potential; character samples were analyzed to determine their quality and impurities; and pioneer metallurgical investigations were made on character samples to present their metallurgical problems. Some factors influencing past and potential western iron markets are discussed. The location, features, qualities, extent, and potential of iron occurrences and some associative resources--limestone and dolomite, coal, petroleum and natural gas, power, and water are discussed. The most abundant iron minerals are magnetite and hematite. The higher grade deposits are extensive contact-metamorphic or pyrometasomatic replacements of calcareous Paleozoic to Proterozoic rocks associated with intrusives. Large low-grade deposits of great potential are present as Precambrian taconite, semitaconite-, and jaspilite-like iron formations of magnetite-hematite. Iron occurs also as low-grade concentrations of magnetite in extensive alluvial deposits. Nonferrous metallurgical slags, nearly 100 million tons, are considered a potential source of iron. Various accessory elements are associated with the iron minerals and these pose metallurgical and economic problems.

Jan 1, 1964

By C. M. Harrer

Reconnaissance investigations were made of 129 iron occurrences in Arizona to determine their extent, attitude, and potential; character samples were analyzed to determine their quality and impurities; and pioneer metallurgical investigations were made on character samples to present their metallurgical problems. Some factors influencing past and potential western iron markets are discussed. The location, features, qualities, extent, and potential of iron occurrences and some associative resources--limestone and dolomite, coal, petroleum and natural gas, power, and water are discussed. The most abundant iron minerals are magnetite and hematite. The higher grade deposits are extensive contact-metamorphic or pyrometasomatic replacements of calcareous Paleozoic to Proterozoic rocks associated with intrusives. Large low-grade deposits of great potential are present as Precambrian taconite, semitaconite-, and jaspilite-like iron formations of magnetite-hematite. Iron occurs also as low-grade concentrations of magnetite in extensive alluvial deposits. Nonferrous metallurgical slags, nearly 100 million tons, are considered a potential source of iron. Various accessory elements are associated with the iron minerals and these pose metallurgical and economic problems.

Jan 1, 1964

By PAUL L. FISHER

This bibliography has been compiled by the Bureau in answer to many requests now being received for information on the briquetting coal and other carbons . In addition to publications issued by the Government in printed or mimeographed form, references are included to articles appearing in the technical press and in cooperative reports of work done jointly with states , colleges , and industries . References and patents are arranged in chronological order . Bureau of Mines bulletins , technical papers and Minerals Yearbooks are printed , and are obtainable from the Superintendent of Documents ,. Government Printing Office , Washington 25 , D. C. Reports of investigations , information circulars , and the directories and reports of the mineral industry surveys are published in mimeographed form and may be obtained without charge from the Publications Distribution Section , Bureau of Mines , 4800 Forbes Street , Pittsburgh 13 , Pa . Many Bureau of Mines publications , as well as bound copies of the foreign and American scientific and trade periodicals , may be consulted in technical , college , and large public libraries throughout the country. Dealers in new and second-hand books sometimes have copies of these reports for sale .

Jul 1, 1948

By L. A. Morley

This report summarizes the work performed on Bureau of Mines Contract J0199106, "Portable Trailing Cables, Splices, and Couplers - Design and Installation Considerations," from May 1, 1979 until December 31, 1981. Splice installations and considerations for the possible use of conductive-rubber shielding in low-voltage trailing cables as well as coupler installations in high-voltage cables were the principal tasks. Flammability measurements on cable components and general testing facilities for mine electrical equipment were secondary tasks. Theoretical and empirical data indicate that conductive rubber with high resistivity values is an unsatisfactory shield design for current-sensing fault detection. Elimination of partial discharge in coupler installations requires meticulous care.

Jan 1, 1982

By Jerry B. F. Champlin

NIOSHAn accelerated testing procedure developed by the Bureau of Mines for evaluating commercially available corrosion inhibitors is described. Ultra-sonic agitation of the corrodent solutions and the hot-finished mild steel test coupons was used to evaluate the effects of several variables on the effectiveness of two corrosion inhibitors. Small changes in the weight of the test coupons in both controlled and inhibited corrodents, before and after exposure, affected the precision and accuracy of the results. Minute amounts of oxygen in the systems were found to be causing the relatively large deviations in the corrosion developed in the controlled tests. Microscopic examination of the test coupons revealed that both surface preparation and internal strains resulting from fabrication methods materially affect corrosion behavior.

Jan 1, 1965

By Robert J. Anderson

"Introductory Statement:In melting the nonferrous metals and alloys for foundry and rolling-mill work, even with the best practice, there is always a loss, due principally to oxidation. Melting losses are a serious source of financial loss in brass and bronze practice, but they are especially serious in the case of aluminum and its light alloys because of the relatively high price of aluminum. The indications are that the melting losses in many aluminum foundries of the United States are at times high, and in some plants (especially where certain furnaces are used) they are entirely too high when compared with the average practice. The fact that the oxidation losses in melting aluminum and its light alloys are high is well known, but it is doubtful whether the factors governing the most suitable methods of melting for a minimum of dross are equally well known. The metal losses involved in melting are worthy of especial attention now because of the rapidly growing importance of the aluminum industry.Factors in the operation of furnaces which affect metal and fuel losses:The essential requirements in the commercial melting of any metal or alloy are that the melting losses should be low, the melting should be rapid, and the melting cost should be low. Certainly it may not be possible to obtain these requirements in any furnace selected at random, and it follows that the design and the operation of furnaces for melting different metals are subjects that warrant the most extensive study and tests. As a general rule, in the industrial operation of furnaces, run on aluminum and aluminum alloys, an effort is made to keep the dross and oxidation losses as low as possible. In attempting to hold dross losses low, numerous factors involved in metal melting may be overlooked, or at least disregarded, and the net practical result may be that the furnace is exceedingly wasteful of fuel. In the case of aluminum and its light alloys, the effect of increasing the temperature of melting, at least in an atmosphere containing free oxygen and nitrogen, is to increase the net melting loss."

Apr 1, 1921

By P. L. Woolf

Seven evaluation tests with blast furnace iron bearing burden materials are described. The effects of pellet strength, fines in the burden, decreasing slag volume, pellet size, eliminating stone with superfluxed sinter, and eliminating stone by prefluxing the pellets were determined. Fluxed pellets and fluxed sinter made with the same ore fines were compared. The tests were conducted under cooperative agreements between the Bureau of Mines and North American steel companies. The objectives were to improve blast furnace practice, expand and develop understanding of the operation and theory, quantify the effects of changes, and explore the limitations of operability. This work was part of an extensive program of blast furnace research in experimental blast furnaces at Bruceton, PA conducted in the years 1958 to 1967.

Jan 1, 1984

By W. H. Kerns

The Taylor Creek lead-zinc deposit is on Taylor Creek, approximately 1-1/2 miles from tidewater, at the head of Duncan Canal, on the east side of Kupreanof Island, Petersburg district, southeastern Alaska. The property was located in 1903, and a 30-foot discovery cut was put to the west tank of the creek. Very little prospecting end developing has been done since that time. The property was examined by J. C. Roehm, associate mining engineer, Territorial Department of Mines, Juneau, Alaska, in June 1946. From exposure n the creek, a mineralized zone with possible dimensions of 1,700 feet by 1,000 feet was indicated. The general strike was northwest, and the dip was low and variable to the northwest. During September through November 1948, the Bureau of Mines conducted a project on the property. Four diamond-drill holes, totaling 770.5 linear feet, were drilled from the surface and 280 lineal feet of hand trenching done. The mineral deposit was found to occur as patches that appear to be a replacement in dolomitic limestone. The patches of mineralization are small, irregularly shaped, and irregularly distributed. Maps showing the location of the drill holes and trenches, analyses of the cores from the drill holes, and anal lee of the samples from the trenches accompany this report (see, also, appendixes A, B, and C).

Jan 1, 1950

By Chas. F. Jackson

During the current business depression the Bureau of Mines has received many inquiries concerning placer mining, the prospects for men of small means to make wages by small-scale placer operations, the locations of placer deposits in the United States, methods of working placers on a small scale, and allied subjects. It has therefore seemed desirable to prepare a circular covering, in nontechnical language, the principal questions which have boon referred to the Bureau of Mines for answer. There are a number of bureau publications dealing with placer mining, most of which are now out of print, but which may be consulted in the larger libraries. Other articles on placer mining nave appeared from time to time in the technical press and several good textbooks have been written on the subject. A partial bibliography of this literature appears at the end of this paper. A recent pamphlet published by the Idaho Bureau of Mines and Geology to assist the prospector and inexperienced small operator has received wide and favorable attention and is recommended as a useful reference. In the present paper no attempt will be made to cover the subject of placer mining in a comprehensive manner, but discussion will be confined to elementary questions of particular interest to persons of limited experience.

Jan 1, 1932

By R. E. Kennedy

The presence of combustible gases and vapors in air can constitute n extremely serious explosion hazard. This hazard is even greater when explosive mixtures are confined under high pressures, as the pressure can become tremendous immediately before the container is ruptured. Because of its interest in safety in mining and. allied industries, the U. S. Bureau of Mines has investigated the explosive properties of a number of gaseous and liquid compounds; the results of these investigations have been published in various government papers and journal articles. The increased use of liquefied, petroleum gases has intensified interest in the effect of high pressures on the explosibility of propane-air mixtures. The limits of flammability of natural gas-air mixtures have been determined at pressures ranging from 50 min. Hg to 3,000 p.s.i. As it is known that a combustible. gas or vapor cannot burn or explode when the oxygen content of the atmosphere is less than a certain value, critical values were determined for the oxygen content of atmospheres to which nitrogen had been added as a diluent. In this connection limits of flammability were determined for ethane in atmospheres containing added. nitrogen or carbon dioxide at pressures up to 900 p.s.i.g.

Jan 1, 1951

By Irven A. Jacobson

This literature survey consists of references dealing with gaseous state thermal decomposition reactions of organic nitrogen and sulfur compounds. The reference source for the survey was the Chemical Abstracts from 1930 to 1956, inclusive. Original articles were not studied. The starting date was set at 1930 because previous to this time much of the work is questionable. This report is in three parts: Part I lists nitrogen compounds; Part II, sulfur compounds; and Part III, compounds containing both nitrogen and sulfur. The organization of the classes of compounds is alphabetical: Part I - amides, amines, amino acids, ammonia, azides, azines, azo compounds, heterocyclic nltrogen compounds, hydrazine, nitrates, nitriles, nitrites, nitro compounds and miscellaneous nitrogen compounds; Part II - disulfides, sulfides (including double and triple sulfides), thiols, thiophenes and xanthates; Part III - thioacid amides, thiazoles, thiocyanates and thiuram disulfides. A class formula is included with each class name. The R&apos;s used in these class formulas may refer to hydrogen or to the same or different radicals when more than one R appears.

Jan 1, 1960

By W. S. Landers

Nine high-volatile bituminous Utah coals were carbonized singly and in blends with low-and medium-volatile bituminous coals. Of the 9 coals, 2 are in commercial use as the base coals in blends that produce industrially accept-able metallurgical coke, while 7 are regarded as weakly coking and are not used commercially in coking blends. The carbonization tests were made in a la-inch diameter, cylindrical retort, using 50-pound charges. Sunnyside coal blended with autogenous char generally produced larger and stronger coke than was yielded by straight Sunnyside coal. The volatile matter of the char and the concentration of the char in the blend appear to be important parameters influencing coke size and strength. A blend of 10 per-cent autogenous char of 7.2-percent volatile matter with Sunnyside coal yielded coke that was larger, stronger, and of higher apparent specific gravity than coke produced from an industrial coke oven blend consisting of 15 percent medium-volatile coal and 85 percent Sunnyside coal.

Jan 1, 1967

By Edmund S. Leaver

The Precious Metals Section is concerned primarily with ore-testing problems associated with precious metals and with the analysis and concentration of a large number of the strategic-mineral samples that have been included in the research program of the Bureau of Mines. During the fiscal year 1938-39, 30 projects were completed. The requests for this service are based upon the desire of the sponsor to obtain the best or most satisfactory method for maximum recovery of the minerals. In many instances it is a question of improving present milling practice, with due regard to utilization of present equipment. In others, the probable tonnage available maybe the deciding factor in the choice of a particular recovery method. Under all circumstances the results of tests axe prepared with the thought of aiding a competent metallurgist, familiar with local conditions, to formulate a practical flow sheet or to assist the mill operator to correct known losses. A microscopic examination for identification of the mineral constituents and their association in each ore is always a big help, in planning the tests and may indicate the reason for former troubles or assist with best procedure.

Jan 1, 1940