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By Melvin P. Silverman

The literature on methane-oxidizing bacteria is reviewed in regard to (1) the growth and isolation of cultures by special techniques; (2) the distribution of these organisms in nature and descriptions of individual species; (3) the physiology of methane-oxidizing bacteria as influenced by temperature, light, pH, aerobiosis versus anaerobiosis, and carbon and nitrogen sources; and (4) the biochemistry of methane oxidation revealed by studies with intact cells and subcellular systems. Present practical applications of methane-oxidizing bacteria are limited to prospecting for natural gas and petroleum deposits. Desirable areas for future research are discussed as well as some possible applications such as (1) the removal and/or early detection of methane gas in coal mines by intact cells or enzyme preparations; (2) the generation of electrical energy by microbial fuel cells using methane as fuel; (3) the growth of methane-oxidizing bacteria on methane for their food value; (4) the purification of hydrocarbon gas mixtures using methane-oxidizing or other alkane-oxidizing bacteria; and (5) the synthesis of methane from mixtures of H2 and CO or H2 and CO2 by me thane-forming bacteria.

Jan 1, 1964

By Melvin P. Silverman

The literature on methane-oxidizing bacteria is reviewed in regard to (1) the growth and isolation of cultures by special techniques; (2) the distribution of these organisms in nature and descriptions of individual species; (3) the physiology of methane-oxidizing bacteria as influenced by temperature, light, pH, aerobiosis versus anaerobiosis, and carbon and nitrogen sources; and (4) the biochemistry of methane oxidation revealed by studies with intact cells and subcellular systems. Present practical applications of methane-oxidizing bacteria are limited to prospecting for natural gas and petroleum deposits. Desirable areas for future research are discussed as well as some possible applications such as (1) the removal and/or early detection of methane gas in coal mines by intact culls or enzyme preparations; (2) the generation of electrical energy by microbial fuel cells using methane as fuel; (3) the growth of methane-oxidizing bacteria on methane fur their food value; (4) the purification of hydrocarbon gas mixtures using methane-oxidizing or other alkane-oxidizing bacteria; and (5) the synthesis of methane from mixtures of H2 and CO or H2 and CO2 by methane-forming bacteria.

Jan 1, 1964

By Stanton L. Tainter

When the disruption of gold mining stopped the usual source of siliceous flux needed by copper smelters , sandstone copper deposits in northern Arizona offered possibilities as a source of the flux during the war emergency . The Federal Geological Survey , while making a comprehensive survey of sandstone copper deposits , investigated the Warm Springs mining district in northcentral Coconino County in August 1943. A month later , J. H. Hedges , chief of the Tucson Division , Mining Branch , Bureau of Mines , examined the operations in connection with an application for an access road . Both investigations concluded that the district , as an emergency source of copper-bearing siliceous flux , had considerable merit , provided high prices for copper continued in effect . Early in 1944 , V. M. Ryan and S. B. Atherley requested assistance from the Bureau in exploring various deposits on their property . The Bureau / drilled 152 holes , aggregating 3,756 feet , on the Petoskey and Mackin groups of claims . This report is based upon churn drilling done under contract from October 7 to November 25 , 1944 .

Feb 1, 1947

By Clayton M. Rumsey

The U.S. Bureau of Mines investigated prospects and mineralized areas in and adjacent to the Indian Pass and Picacho Peak study areas in 1983 and 1984. The Indian Pass study area contains 33,640 acres and the Picacho Peak study area contains 5,450 acres. The study areas are located in the southeast corner of California and are underlain by Precambrian gneiss, Pre-Tertiary metavolcanic and metasedimentary rocks, and Tertiary volcanic and non-marine clastic rocks. Low-grade gold-silver resources may be present in hydrothermally altered gneiss in the upper plate and altered schist in the lower plate of the Chocolate Mountain thrust fault. The thrust fault is exposed in the study areas for about 3.5 miles west and 5 miles east of Indian Pass. Mineralized zones in the thrust plates were not discovered until 1983. Earlier prospecting explored areas containing minor copper carbonate occurrences in schist and sedimentary and volcanic rocks that are younger than the thrust. Twenty-three mines, prospects, and mineral occurrences inside the study areas and fourteen outs; de were examined for this study. These surficial copper occurrences have been prospected extensively in the study areas; large areas have been scraped, pitted, and trenched by bulldozers. However, they appear to be of limited economic significance. Slightly mineralized zones are in the northwest part of the Indian Pass study area where granite contacts sedimentary and volcanic rocks.

Jan 1, 1986

By H. D. Hess

This report describes in detail a unique occurrence of fersmite, (Ca, Ce, Na) (Cb, Ti, Fe, Al)2 (0, OH, F)6, which occurs as small anhedral inclusions and intergrowths with a tantalum-free columbite found in the metamorphic complexes of Ravalli County, Mont. Chemical and crystallographic data along with the physical and optical properties agree in general with those given in the original description of fersmite from the Ural Mountains of Russia. X-ray diffraction data not given in the original description and more specific optical data have been determined. The Montana fersmite, now established as the second occurrence of this rare calcium-columbate mineral, was discovered during a routine Bureau of Mines mineralogical examination of a prospector's sample.

Jan 1, 1960

By Norman A. Pace

This paper is one of a series being published by the Federal Bureau of Mines on methods and practices used in mining and preparing crushed stone for market. Performance, in terms of units of work or tons produced per machine and per operator man-hour, is given whenever that information can be obtained. Direct operating costs are useful for comparing different methods and are included, if available. In addition to describing equipment and methods used} the Bureau considered it desirable to discuss the engineering reasons for the choices that have been made. This paper is particularly concerned with operation of the Camak quarry and plant of the Weston-Brooker Co. The quarry and plant are near Cedar Rock, north of State Highway No. 80 and east of Middle Creek in Warren County, Ga., and about 40 miles west of Augusta. Rail access is by a spur line of the Georgia Railroad from Camak, 5 miles southwest. The main office of the company is at Cayce, S. C.

Jan 1, 1959

By W. W. Cutler

An oil-field drilling campaign is used in this paper to signify the spacing of the wells to be drilled as well as the drilling program, which is interpreted as the number of wells drilled in a unit of time, This has an important bearing upon the time of receiving income, as well as upon the amount of revenue obtained In periods of low prices for oil, such as the present, the margin of profit is at the best very small, and the correct determination of the drilling campaign may be the deciding factor between incurring financial loss or gain during the depressed period. General policy of the operator. Drilling should be planned by the field engineer to conform with the general policy of the operator. This policy may be one of conservation daring the early life of the property, but as mentioned later, this may result in a smaller ultimate recovery it often occurs that the market price of oil does not warrant rapid development, or it may be desirable to hold in reserve a supply of oil for a refinery. The policy may be to recover all of the oil as quickly as possible, or it may be to maintain a constant and sustained production. In any case, the operator should, outline as far as possible a definite policy, and should understand the principles underlying the recovery of oil, the influence of rapidity of drilling and effects of spacing, in order that he may obtain the oil as required with the least expenditure.

Jan 1, 1921

By Thomas L. Vandergrift

This U. S. Bureau of Mines (USBM) report evaluates three stress-transfer-modification concepts for their potential in reducing longwall gate road stresses and closures. In each of the three concepts - packwalling, gob infilling, and entry filling -support structures are constructed on the headgate side of the panel parallel with or inby the face line. When the headgate becomes the tailgate of the adjacent panel, these structures are in place to accept stresses transferred from the mined-out panel. Using the USBM nonlinear boundary-element program MULSIM/NL, baseline models of typical longwall stress transfer behavior were developed for both intermediate depth and deep mining conditions. These models were verified by comparing model results with field measurements and observations. The stress-transfer-modification concepts were then incorporated into the deep baseline model to quantify the effects of each concept on tailgate closure. Modeling results indicated that entry filling is the most effective concept in reducing tailgate escapeway closure. Using only 18 m3 of a weak fill per meter of face advance (7.3 yd3 per ft of face advance), tailgate escapeway closure was reduced by 33%. By improving the quality of the fill, similar results were achieved using 50% less volume.

Jan 1, 2010

By R. Karl Zipf, Z. T. Bieniawski

"A set of fracture profile photomicrographs is presented for fractures generated under mixed mode loading of the Pittsburgh coal. The fractal dimension is used· to characterize the irregularity of these profiles and a tentative relationship is presented between the fractal dimension and the fracture toughness. Surface roughness appears to depend solely on the stress intensity and no other dependence was observed with fracture loading mode, loading rate· or specimen orientation. Observations of crack bifurcations.in fracture profiles can indicate crack growth direction whereas direct surface observations generally cannot in materials such as rock and coal.1 INTRODUCTIONThe production of fine fragments of material as a result of some loading event occurs in many industrial processes. In crushing and grinding, the efficient production of fine fragments is the desired end result; .however, in coal cutting, the production of fine fragments may lead to high levels of respirable dust in the immediate atmosphere with the danger of human lung diseases. Two of the most important sources of fragments in the 1 to 10 micron size range during a cutting process are 1) severe crushing in a zone near the loading tool and 2) subsequent shearing along major crack surfaces that form the larger fragments during material reduction. These and other sources of fine fragments generation are discussed by Roepke (1984) and Zipf and Bieniawski (1986). The physical character of the nearly created major crack surfaces is believed to have a strong influence on the amount of fine fragment generation that occurs during subsequent shearing movement. When the major large fragments initially form, they are ""locked"" in place by the irregular character of the new fracture surface. Only after some relative motion has occurred between fragments are they actually liberated, and the net result is the formation of additional fine fragments. The fine fragmentation is not necessarily limited to the shearing of high points from the macrocrack surf ace since material remaining in the wake of the crack tip is damaged to a substantial depth below the actual crack surface."

Aug 31, 1989

By E. V. Cilento, K. A. DiGregorio, R. C. Lantz

"K. A. DIGREGORIO, E. v. CILENTO, AND R. c. LANTZ. Measurement of superoxide release from single pulmonary alueolar macrophages. Am. J . Physiol. 252 (Cell Physiol. 21 ): C677-C683, 1987.-An electrooptical method was developed to quantify superoxide (02) release from single rat pulmonary alveolar macrophages (PAM) during adherence to the bottom of a culture dish. This was done by measuring the reduction of nitro blue tetrazolium (NBT) to a diformazan precipitate at 550 nm from videorecorded images of individual cells. Temporal changes in cell optical density, which are proportional to the mass of diformazan produced, were calculated from videophotometric measurements of the change in light intensity over individual cells. Total diformazan produced increased 78 and 1263 with an increase in NBT from 0.5 to 1.0 and 2.0 mg/ml, respectively. Total diformazan produced and maximum rate of production among individual PAM varied two- to threefold providing strong evidence for heterogeneity in 02 production. Specific inhibition of 02 production by superoxide dismutase, iodoacetate, and chlorpromazine significantly reduced the total diformazan produced and maximum rate of diformazan production. Hydrogen peroxide was not involved in NBT reduction, since catalase alone did not significantly change diformazan production. This novel method to quantify 02 release from single PAM should be valuable in analyzing heterogeneity and single cell kinetics of O; production, in assessing the effects of exposure of cells to particulates on O; release, and in relating release to electrophysiological measurements.rat; nitro blue tetrazolium; macrophage heterogeneity; single cell kinetic PULMONARY ALVEOLAR MACROPHAGES (PAM) protect the lungs by phagocytizing foreign debris and bacteria (24). This process involves ingestion as well as destruction of foreign matter. Phagocytosis is usually accompanied by a respiratory burst that increases cellular oxygen consumption and glucose metabolism in the hexose monophosphate shunt (7), which leads to the release of highly reactive oxygen metabolites at the surface of the · plasma membrane (6, 27). These agents have been implicated in the killing of bacteria by phagocytes (22), but have also been shown to be toxic and have been linked to cancer, emphysema, arthritis, diabetes, and other diseases (17, 22, 30). Toxic effects may be a result of either an abnormally low production of metabolites, resulting in damage to lung tissue by respirable bacteria and dusts, or an abnormally high production, resulting in direct damage to lung tissue by metabolites themselves."

Jan 1, 1989

By Suresh K. Bhatt

Although overall worker productivity for U.S. underground coal mines is available, productivity by mining method and seam thickness is not. Mining technology has gone through dramatic changes in the past decade, and the industry has experienced a lack of accurate productivity Figures addressing these changes. This information is of great interest in planning for future mining systems as thick and shallow coal seams currently being mined are depleted and exploitation of thinner, deeper, and better quality seams is considered to partially meet the requirements of the 1990 Clean Air Act Amendments. In a cooperative program, the U.S. Bureau of Mines obtained raw mine level production and related data from U.S. Energy Information Administration for 1989 and 1990 and performed the needed statistical analysis. Base criteria, parameters, and salient results of the mine productivity analysis are presented in this report.

Jan 1, 1994

By P. A. Wasson

The investigation described in this publication was conducted by the Bureau of Mines to determine the effectiveness of the anionic silica flotation method on goethitic iron-bearing materials from the Cuyuna Range, Minn. Samples used in this investigation were a composite of drill core from 13 holes, and 3 samples from lean ore stockpiles. These samples are believed to be typical of the mineralization occurring in an area with a potential reserve of several million tans of submarginal iron ore. Results from batch tests showed that the iron-bearing minerals could be effectively concentrated by flotation removal of the siliceous gangue. The drill hole composite yielded laboratory flotation concentrates from locked tests containing 56.8 percent Fe and 6.1 percent silica, with an accompanying iron unit recovery of 94.2 percent. Concentrates containing 52.4 to 53.7 percent Fe also were produced from the lean ore stockpile materials; corresponging iron recoveries ranged from 71 to 79 percent in the batch tests, with the possibility remaining for additional recovery of iron from the middlings.

Jan 1, 1963

By M. H. Chetrick

An important factor in the design and operation of a lignite-gasification plant is knowledge of the thermal requirements. These not only vary with different-size plants but also with the operating conditions for a plant of given capacity. Thermal data have been collected since 1945 from a commercial-scale lignite-gasification pilot plant operated by the Bureau of Mines at Grand Forks, N. Dak. The description and operation of this plant and a study of the gas-composition data have already been described in previous reports (1, 2, 3, 4, 5).2) / This investigation was made to review the thermal data taken in tests and to correlate them in terms of the fraction of undecomposed steam and the H2:CO ratio.

Jan 1, 1953

By Errol D. Sehnke

This U.S. Bureau of Mines report provides detailed information on worldwide alumina production capacity by plant and country. The information was compiled from a variety of domestic and international sources and was based on information available to the Bureau through December 31, 1993. Capacity data represent announced installed and planned capacities and do not necessarily reflect a Bureau of Mines judgment of actual plant operating levels or timing of planned expansions, The year-end capacity is the ?nameplate" capacity or estimated production capacity, whichever is larger.

Jan 1, 1993

By A. B. Hooker

Many attempts have been made to develop methane detectors that will be safer and more accurate than the flame safety lamps used to detect methane in mines. The development has taken two general forms, namely: (1) Methane detectors, in which the evidence of methane depends entirely upon changes in the appearance of the detecting element, such as a flame or filament; (2) indicating methane detectors or those equipped with scales upon which the approximate percentage is definitely indicated. As an aid in the development of suitable detectors, the United States Bureau of Mines has assembled and published in its Schedule 8B a set of minimum requirements which tests and experience have shown desirable for methane detectors. Any manufacturer may submit his detector for inspection and tests leading to approval under this schedule.

Jan 1, 1930

By Thomas J. Blalock

The volumetric determination of uranium according to the method of Sill and Peterson (6),3/ which uses cerate oxidimetry after the separation of interferences such as sulfides and cupferrates, has been used for some time by the Bureau of Mines and gives satisfactory results for many of the samples tested. However, in those instances where the uranium content did not exceed a few tenths of 1 percent and iron was present in the range of 10 to 40 percent (as Fe203),4/ the method was cumbersome and unreliable. The need for a more accurate procedure for the determination of small amounts of uranium in the presence of large amounts of iron, such as in shale or black sands, prompted this investigation. The Bureau desired that materials containing as little as 60 p.p.m. of uranium be assayed within reasonable limits of accuracy. One of the primary aims of this work has been to eliminate, as far as possible, the necessity for repeated cup ferron extractions.

Jan 1, 1960

By Stephen D. Cramer

The Bureau of Mines conducted a study in which the magnetic fraction of urban refuse was used as melting stock in the preparation of high-strength, low-alloy and carbon steel. Product steels, made from incinerated steel can scrap, nonincinerated-nondetinned steel can scrap, nonincinerated-detinned steel can scrap, and dilutions of these scraps with No. 1 heavy melting scrap, were used in continuing tests in industrial, rural, and marine environments to determine the effect of residual elements and atmospheric pollutants on their atmospheric corrosion resistance. The respective commercial steels were exposed at the same time to establish baseline corrosion data for the test sites. Weight-loss data are reported for atmospheric exposures of 0.5, 1.0, 1.5, and 3.8 years. The marine environment was the most corrosive; the industrial environment was the least corrosive. The atmospheric corrosion resistance of the carbon steel was improved 25 pct by using incinerated scrap and nonin-cinerated-nondetinned scrap in the steelmaking process. In no case was the atmospheric corrosion resistance of carbon steel degraded by using the magnetic fraction of urban refuse as melting stock. The presence of sulfur in the corrosion film was the most important factor affecting the corrosion resistance of the steels. With increasing sulfur concentration, the rate of the corrosion reaction was reduced and the corrosion film became more protective. The residual elements in the product steels most responsible for improving corrosion resistance were copper and tin. These elements tended to increase the concentration of sulfur in the corrosion film. At the levels present in the product steels, Cr, Ni, and Pb had no observable effect on the corrosion resistance of the steels.

Jan 1, 1980

By Jr. Joyce

This report describes sulfatization of nickeliferous laterites from Puerto Rico and the Philippines for recovery of water-soluble nickel and cobalt sulfates. Temperatures ranging from 665 C to 710 C and a 10-percent sulfur dioxide-air reaction gas were employed during batch-roasting tests and during continuous countercurrent treatment in a 2-inch-diameter shaft furnace. A maximum of 69 percent of the nickel and 76 percent of the cobalt were recovered from one sample of Puerto Rican laterite, and a maximum of 96 percent of the nickel and 91 percent of the cobalt were recovered from the Philippine laterite.

Jan 1, 1965

By Lee M. Manna

Approximately 10,000, 10-Ton, 4 wheel, 2 truck, coal mine cars are in general service in U. S. Mines. None are equipped with an automatic braking system. Very few are equipped with hand or parking brakes. The report lists major manufacturers of the car and develops estimate as the percentage represented. It complies physical specification of cars of major car manufacturers, and develops a composite clearance diagram. It then discusses a pneumatic system employing truck components for an automatic system that could be used as an add-on unit. The components are listed and priced and a schematic circuit is developed for the system. Recommendations as to future programming are made.

Jan 1, 1976

By D. W. Frommer

As one phase of a general problem of recovering sulfide slimes, mineral-dressing research was conducted on flotation tailing from the St. Joseph Lead Co., Bonne Terre, Mo., mill to recover a significant portion of the residual, finely divided galena. Production of a high-grade concentrate was not part of the immediate objective. Only a reasonable ratio of concentration of lead sulfide slime was sought, since the problem of upgrading by mechanical or extractive processes would be considered in the later stages of this study. The results show that, from a feed material averaging 0.20 percent lead (about 70 percent finer than 400-mesh), a recovery of up to 45 percent could be effected by flotation in rougher concentrate analyzing up to 6.5 percent Pb. These results were obtained by using larger quantities of various xanthates and sodium sulfide than used customarily in mills. Sodium sulfide, which is ordinarily detrimental to flotation of galena, was beneficial in this case.

Jan 1, 1959