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By Natalie A. Sapola, Knox Van Dyke, Jean Rabovsky, Vincent Castranova, William H. Pailes, Melanie McPeek, Deloris J. Judy

"INTRODCJCTJONPlatelet activating factor (PAF) is a glycerophospholipid (1-0-alkyl-2-acctyl-sn-glycerol-3-phosphoryl choline) which has been shown to mediate a broad range of biological activities. 1·3 Its pulmonary actions include contraction of pulmonary tissue,4 secretion of leukotrienes from leukocytcs,5 airway constriction,6 pulmonary edema,7 and enhanced migration of neutrophils into the airspaces of thelungs.8-9PAF can be released from several different cell types, such as, basophils, neutrophils and alveolar macrophages, in response to a variety of particulates or membrane stimulants which include zymosan, calcium ionophore, phorbol esters, chemotactic agents, and endotoxin. 1~1 3 Therefore, PAF may play an important role in the development of pneumoconioses by mediating pulmonary responses of lung cells to a variety of occupational dusts. To investigate this possibility, we determined the effects of P AF on several physiological parameters of neutrophils, alveolar macrophages, and alveolar type Il epithelial cells.METHODSIsolation of CellsNeutrophils were isolated from human blood by dextran settling and centrifugal elutriation.14 Isolated neutrophils (93% pure) were resuspended in HEPES-buffered medium (145 mM NaCl, 5 mM KCI, 10 mM HEPES, 5 mM glucose, and 1 mM CaC12; pH = 7.4). Cell number and volume were determined with an electronic cell counter equipped with a sizing attachment.Rat alveolar macrophages were obtained by pulmonary lavage with ea2+, Mg2+-free Hanks balanced salts solution. 15 Alveolar macrophages (94% pure) were resuspended in HEPES-buffered medium, counted, and sized electronically.Rat alveolar type Il cells were isolated by enzymatic digestion for 35 minutes at 37°C with 40 µ/ml type I elastasc and 0.1 % collagenase and purified by centrifugal elutriation. 16.17 Type Il cells (92 % pure) were resuspended in HEPES-buffered medium for measurement of membrane potential, oxygen consumption, and trypan blue exclusion. Type Il pneumocytcs were resuspended in 0.1 M NaCl plus 0.05 M HEPES (pH = 7.8) to measure cytochrome P450-dependent activities and aggregation. Cell size and number were determined electronically."

Jan 1, 1990

By A. Wahab Khair, Richard D. Begley

"This paper presents results of destructive tests performed on rectangular coal specimen under the influence of two vertical and simultaneous wedge indentation forces. Several wedge designs and spacings were utilized in compression tests. The objective of these experiments was to qualitatively monitor the effect of different wedge designs and spacings on the stress distribution within the coal specimen.Coal samples from the Waynesburg coal seam were cut and trimmed to cubical dimensions of approximately 5 X 10 X 20 cm. These specimen were subjected to parallel compressive forces through two vertically applied wedge indentors. Loading was achieved with a hydraulic hand pump in order to facilitate interferogram construction. The load increments were limited due to the sensitivity of the holographic interferometric technique (holometry) in measuring small displacements; therefore, interferograms were taken only during similar increments in order to allow for a qualitative comparison between different wedge design and spacings. In some cases, interferograms were taken immediately before and after failure of the specimen.Introduction Failure Modes Three distinct modes of failure occur when geologic materials are subjected to wedge indentation forces. As shown in Figure 1, a crushed zone is located immediately adjacent to the indentor while chipping can occur if the fractures initiated in the crushed zone extend upwards to the free surface.. The third failure mode is a zone of intricate frac¬tures located between the crushed zone and the chipping zone. Several experiments have been conducted over the years to better understand crater formation and stress distribution within geologic materials under the influence of an indentor. Generally speaking, crack initiation and propogation observed in these experi¬ments correlate fairly well with wedge indentation theory; however, the nature of the .fractures is greatly influenced by different material properties such as grain size and cleavage planes. In other words, a wide range of behavior has been found in different rocks subjected to wedge penetration. For example, it has been observed that some rocks are merely crushed and indented while others are more prone to cracking and chip formation. Therefore, the development or nondevelopment of chips depends mostly on wedge geometry, rock type and depth of penetration. This work is part of the study associated with opti¬mization of cutting parameters, which is best modeled by using brittle materials and subjecting them to rigid wedge penetration tests."

Jun 1, 1988

By C. H. Riggs

This petroleum-engineering study of the Healdton oil field in Carter County, Okla., describes the geology and production history of that field and estimates the oil reserves that could be produced by efficient secondary-recovery methods. The Healdton field, in western Carter County approximately 20 miles west of Ardmore, Okla., was discovered in 1913 and was one of the early important oil-producing areas in the State. Although the volume of oil recovered from the Healdton sands has been comparatively high, studies show that a large reserve remains in the pressure-depleted sand, which can be recovered by efficient water-flood operations. In making this study of the Healdton-sand reservoir, the writers utilized many data already available in company and Government offices. Most of the fluid samples were collected by Bureau of Mines personnel and analyzed in the Bureau's laboratories at Bartlesville, Okla.; but other data, including logs, core analyses, and production records, were obtained from outside sources. These data were examined critically but were not verified, and possible errors in the original data may be reflected in the conclusions. In this study, attempts were made to consider only those aspects of the available information that would contribute to a clear and concise engineering report on the Healdton-sand reservoir. Other phases of the data, as well as those concerning associated reservoirs, were eliminated from consideration as being irrelevant to the particular problem. Cores and drill cuttings of the Healdton sands were analyzed and studied to determine the nature of the reservoir rocks. Analyses of samples of produced oil, water, and gas were studied to fix the different types, the limits of their occurrence, and the suitability of different waters for injection into the Healdton sands. Records of oil, gas, and water produced and of gas and water injected were studied to interpret the production behavior of the field and of certain individual leases. Theoretical calculations were made to predict the probable water-flood behavior and oil recovery, at constant water-injection rates, for individual sands on two leases.

Jan 1, 1953

By Bill Linville

During calendar year 1972, the Bureau of Mines was engaged in some 20 major areas of research for the development of new and improved efficient methods of conservation and utilization for petroleum and natural gas, oil shale, and coal. Made up of numerous projects described in this report, the program was carried out through research performed at research centers and laboratories in the field supervised and supported by administrative personnel of this Bureau of the Department of the Interior. Based un this research, 186 technical reports were published by the Bureau or others, and numerous other reports were prepared for Federal agencies, State agencies, and organizations engaged in cooperative research programs with the Bureau.

Jan 1, 1973

By R. S. Dean

The original flotation reagents were certain oils selected for a combination of properties that occurred fortuitously. It was recognized quite early in the study of flotation mechanism that, in order to function, an oil must have an active group-one that differs from the remainder of the molecule in its affinity for water or the mineral particle. Wark4 gives credit for recognition of this elementary chemical principle to the senior author of this report.5 However, it was soon found that simple hydrocarbons could not be used as flotation reagents and that two of the functions, which were combined in the early flotation oils such as pine and eucalyptus, could be obtained in separate compounds and their relative intensity controlled to advantage. These two functions were called collecting and frothing.

Jan 1, 1944

By Galen H. Clevenger

Although there are exceptions, oxidized silver ores containing the higher oxides of manganese are generally refractory to hydrometallurgical methods of treatment. When these ores are of high enough grade they can be smelted; indeed, some rather low-grade ores of this type have been smelted at a profit because of their fluxing value. In the past, when these ores could not be smelted, they either were not treated or were treated at low efficiency, generally by cyanidation. The need for thorough investigation of the problem was therefore evident for some time before the writers began their research. The problem of treating manganese-silver ores seems to have been recognized first about 35 years ago by C. W. Goodale in applying pan amalgamation at Tombstone, Ariz. He attributed the low extraction of silver to the fouling of the mercury by manganese rather than to the presence of a refractory compound of manganese and silver. Although definite knowledge as to the cause of the poor extraction of silver was lacking, a more or less effective preliminary treatment, that is, a chloridizing roast, was applied.

Jan 1, 1925

A preliminary program dated April 25, 1974 was prepared for Development Engineering, Inc. (D.E.I.) on research and development, laboratory; field and other engineering studies for the disposal of retorted oil shale. This program was revised and published as a final document dated December 17, 1974. The document included a discussion on the peculiarity of retorted shale materials to be investigated and a discussion of the various laboratory and field tests which would need to be conducted to define their physical and chemical properties. The proposed research and development program was divided into eight work phases as follows: I - Program Development II - Exploratory Laboratory tests on old U.S.B.M., retored shale III - Laboratory tests on Pilot Plant retorted shale IV - Laboratory tests on retorted shale from Semi-Works Plant, and field and test plots and ponds. V - Field compaction tests

Jan 1, 1975

By T. A. Klinefelter

ONE OF THE many services rendered by the Federal Bureau of Mines is the identification and general examination of ore and mineral samples. Many of these, coming from almost every State in the Union, are clay and shale samples. Other Government agencies, State geologists, universities, and other laboratories are often requested to make similar examinations. This publication describes methods of testing these samples. An earlier paper, published in 1943, described Bureau of Mines methods of testing such clays.3 This paper was to be followed later with another (part II) that would describe much more thorough testing than did the rather general outline of part I. Part I has been out of print for some time and needs revision, and part II was never written; hence, the present publication is designed to include part I and also those additions intended as part II. The tests presented in part I were simple, requiring only the ordinary equipment to be found in any good chemical laboratory. The second publication was to include a greater number of test procedures and information on increasing the accuracy and precision of those previously given.

Jan 1, 1957

By B. M. O'Harra

Zinc smelting is frequently termed a ba.ckward art. The term is hardly true, for great progress has been made in recent years in the design and in the thermal efficiency of the retort furnace, in the quality of retorts, in the recovery of zinc, and in the ability to treat more impure and complex ores. The fact remains, however, that the peculiar physical and chemical properties of zinc have delayed such immense advances-large smelting units, high recovery, lowunit costs, and ability to treat low-grade ores-as have been made in the metallurgy of lead and copper. In current retort-smelting practice, the ores, if carbonates, are calcined to remove carbon dioxide; or, if sulphides, are roasted to remove sulphur. The sulphur must be eliminated as completely as possible, usually to less than 1 per cent. This means that the roast must be continued for a long time at a high temperature, with resulting high cost and small capacity per furnace. The roasted ore is mixed with about 50 per cent of its weight of reducer, which may be fine coke, anthracite, or nonbituminous coal. This mixture is charged into horizontal fire-clay retorts. The retorts used in this country are about 8 inches in internal diameter by 4 feet in length and hold 50 or 60 pou~ds of ore. The diameter of the retort is limited by the tirrie required for the heat to penetrate to the center of the charge; the length by the strength of the retort, which at the high temperature employed can not support the weight of the charge if the span is more than about 50 inches. The retorts are heated externally by coal, natural gas, qr ·producer gas to a temperature of 1,200° C. or more. The zinc oxide is reduced to zinc, which is volatile at this temperature, and passes into a conical fire-clay condenser. attached to one end of the retort, where it conde_nses to liquid zinc and is removed. Twenty-four hours are required for distillation, and because of the low heat conductivity of the retort walls 11.nd of the ore charge itself, the heat efficiency even of the most modern regenerative furnacei;; is only about 12 per cent. The retorts have a short life, 30 to 6Q days, at the high temperature required-; zinc losses are heavy, usually 10 per cent or more; and the proportion of impurities in the retort charge must be carefully controlled to prevent the rapid corrosion of retorts. For these reasons, much work has been done in an e:ff ort to, find cheaper and more efficient methods o.f recovering zinc from its ores. Various methods have been proposed for smelting in the blast furnace. Some of these contemplated the production of zinc vapor and its condensation to liquid; others attempted to produce liquid zinc directly by smelting under pressure. It is now realized that fundamental difficulties render these proposals impracticable. The electric furnace for smelting offers obvious advantages in the way of the efficient utilization of energy, large units, easy attainment of high temperatures, and the possibility of treating complex ores. E. H. and A. H. Cowles first suggested a design for an electric furnace for the reduction of zinc ores and patented their process in 1885. Their attention was soon directed to other uses for their furnace and nothing further of importance was done in the electric smelting of zinc until about 1900. Several investigators then started work upon various processes and had more or less success. The chief difficulty they encountered was the impossibility of obtaining more, than a small amount of the zinc as liquid metal because most of the zinc vapor condensed as blue powder. Interest in the electrothermic metallurgy of zinc increased, many patents on processes and furnace design were taken out, and the literature on the subject grew, until in 1914 and 1915 the problem seemed to be approaching solution. About this time the hydrometallurgy of zinc, the development of which had been lagging somewhat behind that of the electrothermic metallurgy, sprang into the limelight and a commercial process was soon perfected. This rapid development, perhaps aided by the war premium on the high-grade spelter produced by electrolytic deposition, distracted attention from electric smelting to some extent, though progress continued. With the perfection and standardization of the electrolytic process has come a better realization of its limitations, especially the necessity for large-scale operation ·and the difficulty of obtaining high extraction. Because of these limitations the electrothermic metallurgy of zinc still has a field of its own and in fac-t promises to become a strong competitor of both hydrometallurgy and retort smelting except under conditions highly favorable to the latter methods. Because of the imperfections of the retort and electrolytic processes and the promise that the electric furnace offers in overcoming these imperfections, the. United States Bureau of Mines, in cooperation with the Missouri School of Mines and Metallurgy, has undertaken a study of the electrothermic metallurgy of zinc.

Jan 1, 1923

By Alla D. Mah

The heat of combustion of TaC0.996 was determined by oxygen bomb calorimetry to be -302.8 ±0.4 kcal/mole. The corresponding heat of formation of TaC0.996 is -35.4 ±0.5 kcal/mole, and the calculated heat of formation of TaC1.00 is -35.5 ±0.5 kcal/mole.

Jan 1, 1965

By K. K. Kelley, W. W. Weller

Heat capacity measurements of lead molybdate and lead tungstate were conducted over the temperature range from 51 ° to 298 ° K. The entropies were found to be S298.15 = 39.7 ± 0.5 cal / deg mole for lead molybdate and S298.15 = 40.2 ± 0.5 cal / deg mole for lead tungstate . The entropy values were combined with other pertinent data to obtain the entropies of formation of the two compounds from their constituent elements and oxides .

Jan 1, 1964

By Charles Janin

The recovery of gold from sands and gravels is one of the oldest forms of mining; it antedates history and has been practiced by savage peoples. In North America the search for placer gold has been a powerful agency in the exploration and development of unknown regions and has profoundly influenced the course of our civilization. With the progress of invention, the improvements in machinery, and the availability of large capital for the conduct of great operations, the tendency in placer, as in many other branches of mining, has been toward the working of extensive but comparatively low-grade deposits. The early miner washed the rich spots in stream beds or terraces with his pan, his long tom, and his primitive sluice. Then followed the growth of hydraulic mining and the use of giants supplied with water under pressures of hundreds of pounds to the square inch that could work at a profit gravels whose gold tenor was less than 3 cents to the cubic yard. Finally came the dredge that could handle deposits lying so far below water level as to be beyond attack by other methods. Although the gold dredge was first successful on a commercial scale in New Zealand, it has reached its present strength and efficiency in this country and its development is a monument to the daring, per- severance and technical skill of the many men, mine owners and engineers who have each contributed something to the final result. The Bureau of Mines, authorized to conduct investigations for the purpose of increasing efficiency in the mineral industries, had its attention called some years ago to the need of a comprehensive report on gold dredging in the United States. The director of the bureau recognized that such a report should summarize the development of the gold dredge, should describe in detail the essential features of present-day dredges, should discuss the facts that determine whether a placer deposit can be profitably dredged, and should point out the approved methods of prospecting placer ground and of operating dredges. At the request of the director, the author undertook the preparation of such a report and has been intermittently engaged on the task for several years. This bulletin is the outcome of his labors. He hopes that it will prove of interest to designers and builders of dredges, to mining engineers, and to persons who may contemplate investing capital in placer-mining ventures.

Jan 1, 1918

By W. W. Weller

Low-temperature heat capacities of scandium sesquioxide (Sc203) and a mixture of cerium sesquioxide (Ce203) and cerium dioxide (CeO2) were measured over the temperature range from 50° to 298° K. The entropy of scandium sesquioxide at 298.15° K was evaluated directly as S°298.15 = 18.4 ± 0.1 cal/deg mole. That of cerium sesquioxide was extracted by combining the heat-capacity data for the mixture with those for pure cerium dioxide; the result was S298.15 36.0 ± 1.0 cal/deg mole.

Jan 1, 1963

By W. M. Myers

The U. S. Bureau of Mines conducted an investigation to determine the cause of the deterioration of Portland cement during storage and transportation , and to discover a means of preventing it . All available printed sources of information on this subject have been examined and a bibliography has been compiled . The subject has also been discussed with the leaders in the cement industry ; the present report is the result of their cooperation , and is based principally on information thus obtained . Deterioration of Portland cement during storage over any considerable period of time has long been noted ; closely related to it is deterioration of cement during transportation, which involves not only the time factor of storage but also exposure to varied climatic conditions . Deterioration in both cases is due to hydration of the cement by absorption of moisture from a humid atmosphere , or by exposure to actual rain-fall . After hydration cement possesses no cohesive power ; the degree of deterioration is directly proportional to the degree of hydration . The amount of deterioration of Portland cement during storage has been accurately determined in an investigation by the Structural Materials Research Laboratory , in cooperation with the Portland Cement Association . Cement stored in a shed in cloth sacks retained 80 per cent of its original strength after three months storage ; 71 per cent after six months ; 61 per cent after one year ; and 40 per cent after two years . The deterioration of Portland cement during storage and transportation was noted particularly in France during the World War . Information concerning cement used by the American Expeditionary Forces was furnished by Lt. Col. H. S. Spackman and Major E. C. Eckel , U. S. R. , who had charge of practically all matters concerning cement used by the A. E. F. The cement used by the A. E. F. came from the following sources : 42,000 tons was French , Swiss , and Spanish cements ; 120,000 tons was English cement ; 55,000 tons made in plants operated by the A.E.F .; 500 tons ( Not over) from America . Deterioration was most marked in cement from the first source .

Jun 1, 1922

By K. B. Bengtson

This task report provides the process technology, preliminary design, capital and operating costs for a 25 TPD pilot plant to produce cell-grade alumina using a clay/hydrochloric acid extraction - HCI gas induced crystallization process. The report consists of six volumes: I - Process Technology and Costs; II and III - Equipment Lists, Specifications and Quotations; IV and V - General Specifications; VI - Drawings. The process was selected by the Bureau of Mines as the more promising method to produce cell-grade alumina from clay based on the results of the two previous task reports under this contract: Task I - Comparison of Six Processes (alunite, anorthosite-lime sinter, clay/sulfurous acid, clay/nitric acid, clay/hydrochloric acid evaporative and gas-induced crystallization) and Task 2 - Comparison of Two Processes (clay/nitric acid and clay/hydrochloric acid - gas induced (crystallization). The pilot plant process utilizes a unique dual crystallization process to produce aluminum-chloride-hexahydrate crystals having sufficient purity when decomposed to meet stringent alumina product specifications. The size of the 25 TPD pilot plant has been selected to permit scale-up to commercial size plants of equipment, technical and economic parameters. The capital cost estimate for the pilot plant, exclusive of fee and escalation, for a southeastern U.S. location is $52,311,000 expressed in 1979 dollars. The total time required to construct the pilot plant including engineering and procurement is 32 months. The operating cost to produce the estimated 9,000 tons of alumina required for testing in Hall cells is $40,91[0],190 expressed in 1979 dollars.

Jan 1, 1979

By Boyd Wise

A jet pump injector was developed and successfully tested, thereby demonstrating the feasibility of a jet injector for introducing coarse coal into an operating slurry face haulage system: In Phase I a variety of injection concepts were evaluated, and the jet pump was identified as best, due to its simplicity, compactness and performance potential. In Phase IIA subscale jet pump injector tests were conducted, and a computer model of a jet pump injector was developed whose performance predictions correlated well with subscale test results. In Phase IIB various system configurations were defined for integrating a jet pump injector into a fully operational underground coarse slurry face haulage system, further highlighting the feasibility and practicality of such a system. In Phase III a full-scale mobile haulage vehicle embodying a jet pump injector and coal sizing equipment was detail designed into a practical vehicle with attractive performance characteristics. More importantly, fully operational full scale jet pump injector -and feeder/breaker subassemblies were tested and proven successful in their ability to down-size coal to 3" in all 3 dimensions and to consistantly provide slurry of 4217 weight concentration at 6.4 TPM throughput under a wide range of operating conditions including zero to maximum feed rate within 5 seconds.

Jan 1, 1985

Graduate education is an integral part of the Center's research program. The scope of. work and the duration of each research project is calculated, in part, by taking into consideration the needs of the graduate research program and graduate training. Full development of student involvement, as demonstrated by the research practicum which is offered to qualified senior undergraduates at Penn State University and is designed to acquaint them with research methods and techniques and inform them of the opportunities available in this field. and the fulfillment of graduate program requirements are of the utmost concern. The Pennsylvania State University and West Virginia University have accredited mining engineering curricula and rank among the schools with the largest enrollment in this area in the nation. The number of undergraduate students enrolled in mining engineering at Penn State and West Virginia University account for nearly 20%, of the total undergraduate enrollment in this discipline in schools across the United States. The Pennsylvania State University. West Virginia University, Massachusetts Institute of Technology, University of Minnesota, and Michigan Technological University, have granted a total of thirty-five (35) doctorate and masters degrees which can be directly attributed to research conducted in the Center.' Of these graduates, fifteen(15) have found employment in the mineral sector of the economy, i.e., in private industry, with government agencies, and at various universities, worldwide. In addition, a number of those graduating with masters degrees are currently pursuing a doctorate degree.

Aug 31, 1989

By H. L. Gibbs

A portable radon monitoring instrument capable of making on-the-spot measurements of the radon gas content of uranium mine atmospheres was designed and constructed. The monitor was tested in the laboratory and in operating uranium mines. Good correlation was obtained between the monitor readings and radon measurements made on mine atmosphere samples taken in radon bottles.

Jan 1, 1973

By William L. Crentz

1. SALES PUBLICATIONS

Nov 1, 1949

By H. W. Busch

In the course of examinations by representatives of the Bureau of Mines of several compressed-air systems in which explosions had occurred, samples were obtained of the carbon deposits that are formed normally in various parts of the systems by decomposition of the compressor lubricating oil. Experimentation with these carbon deposits has demonstrated that they contain a "carbon-oxygen complex" similar to that formed on coal and on other carbonaceous materials and generally recognized as being the cause of spontaneous heating of coal. The exothermic properties exhibited by such a complex are considered significant in relation to the possible initiation of combustion reactions that may lead to explosions or formation of carbon monoxide in compressed-air systems. This report discusses the occurrence of explosions and formation of carbon monoxide in the use of compressed air and presents results of experimentation conducted with carbon deposits from air compressors.

Jan 1, 1949