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By Dean H. Ambrose

Using three-dimensional (3-0) graphics computing to evaluate new technologies for computer-assisted mining systems illustrates how these visual techniques can redefine the way researchers look at raw scientific data. The U.S. Bureau of Mines is using 3-D graphics computing to obtain cheaply, easily, and quickly information about the operation and design of current and proposed mechanical coal and metal-nonmetal mining systems. Bureau engineers developed a graphics simulator for a continuous miner that enables a realistic test for experimental software that controls the functions of a machine. Some of the specific simulated functions of the continuous miner are machine motion, appendage motion, machine position, and machine sensors. The simulator uses data files generated in the laboratory or mine using a computer-assisted mining machine. The data file contains information from a laser-based guidance system and a data acquisition system that records all control commands given to a computer-assisted mining machine. This report documents the first phase in developing the simulator and discusses simulator requirements, features of the initial simulator, and several examples of its application. During this endeavor, Bureau engineers discovered and appreciated the simulator's potential to assist their investigations of machine controls and navigation systems.

Jan 1, 1992

By H. W. Kilau

The U.S. Bureau of Mines is evaluating water spray additives for the purpose of improving respirable dust control during coal mining operations, with particular emphasis on the longwall shearer. Recent field tests of surfactant-polymer reagents at two production longwall operations have shown favorable respirable dust reductions compared with water sprays containing no additive. Gravimetric dust samples obtained by a technician downwind of the shearer while following or preceding the machine showed dust reductions in the range of about 40% to 60% for some of the reagent formulations compared with using water alone. Three polymers were tested: two polyethylene oxide compounds of different molecular weight and hydroxypropyl methylcellulose (HPMC). All were effective for dust reduction, and two were cost effective when used in combination with sodium di(2-ethylhexyl) sulfosuccinate surfactant. How-ever, the use of these reagents requires the longwall operator to be more aware of headgate dust control. Experimental evidence indicates that dust captured by reagent-treated sprays at the shearer can be reemitted in the headgate area if stagcloader-crusher sprays and other dust controls are inadequate.

Jan 1, 2010

By C. H. Fisher

Sulphuric acid of various concentrations has long been used as a reagent in the determination of olefins and aromatics in hydrocarbon oils4 such as gasoline, kerosene, and neutral oils from coal-tar distillates. Despite its long use, however, there is no general agreement as to optimum conditions and concentration of acid, and numerous methods and modifications have been recommended. In most cases, treatment of the neutral oil with 80 to 90 percent sulphuric acid, followed by distillation to the original endpoint to remove olefin polymers, is recommended for the estimation of unsaturated hydrocarbons. The distillate thus obtained is taken as olefin-free oil and used in later stages of the anlysis. Aromatic hydrocarbons generally are determined in the olefin-free oil by suphonation with more concentrated acid (96 to 100 percent and fuming sulphuric acid are recommended), the hydrocarbons not attacked and removed as water-soluble sulphoric acids being considered as saturated hydrocarbons. In some cases the saturates are examined further by differentiating between cyclic (naphthenes) and acyclic hydrocarbons (paraffins), Generally this is achieved by physical methods, although strong sulphuric acid is known to react preferentially with some types of saturated hydrocarbons. It was the purpose of the present work to make a general study of this type of analysis and to investigate the reactions of hydrocarbons under conditions often used in analyses that employ sulphuric acid reagents. Since previous work is not in good agreement, the optimum concentrations of acid for the different stages of the analysis were determined. Several sulphuric acid methods previously recommended and new modifications were compared, two synthetic solutions being used as the reference oil. The results obtained are presented below under separate headings.

Jan 1, 1937

By D. Eugene Rannels, Sarah E. Dunsmore

"Dunsmore, Sarah E., and D. Eugene Rannels. Extracellular matrix biology in the lung. Am. J. Physiol. 270 (Lung Cell. Mol. Physiol. 14): L3-L27, 1996.-The lung and other organs are comprised of both cellular and extracellular compartments. Interaction of these components modulates physiological function at the organ, cellular, and subcellular levels. Extracellular components in the gas-exchange region of the lung include both noncellular interstitium and basement membranes. Connective tissue elements of the interstitium in part determine ventilatory function by contributions to tissue compliance and to resistance of the diffusion barrier. The basement membrane underlies cells of both the alveolar epithelium and the capillary endothelium; basement membrane components exert biological effects on adjacent cells through receptormediated interactions. This review emphasizes current knowledge concerning the composition and biological activity of extracellular matrix in the alveolar region of the lung. Matrix synthesis and turnover are also considered. Directions for future research are suggested in the context of current knowledge of the lung and other model systems. EXTRACELLULAR MATRIXEXTRACELLULAR MATRIX is a general term that encompasses components of the basement membrane and interstitial connective tissue. The extracellular matrix has many functions. It provides structural support, compartmentalizes tissues by separating epithelium or endothelium from interstitium, and serves as a physical barrier. Both in vivo and in vitro studies show that extracellular matrices also affect cell shape and function. The matrix elicits a variety of cellular responses, including adhesion and spreading, changes in cytoskeletal organization and differentiation, formation of focal contacts and stress fibers, stimulation of proliferation and migration, induction of polarity and gene expression, alterations in metastatic activity, and outgrowth of cell processes (for review see Refs. 387, 462). Cellmatrix interactions play roles in embryonic development and organogenesis (for review see Refs. 1, 91), in wound healing (for review see Refs. 145, 327), iri metastasis (for review see Refs. 430, 431), and in angiogenesis (for review see Refs. 185, 186). The extracellular matrix is the subject of a large volume of literature. In 1994, over 1,000 articles contained extracellular matrix in the title or abstract. After a brief discussion of key aspects of extracellular matrix biology, this review will focus on the extracellular matrix of the lung."

Jan 1, 1998

By Benjamin C. Pollard

The location and production potential of a large block of strippable reserves in North Dakota were determined by using published data as a base and adding new drill hole data or other data contributed by companies that presently own or lease coal lands. Only beds exceeding 5 feet in thickness, under less than 120 feet of overburden, and in large blocks of 5 million tons or more were included in the estimates. All such reserves are in the Fort Union Formation of western North Dakota and are lignite in rank. Sixteen large blocks of reserves evaluated in this study are estimated to contain a total of 4.1 billion tons of strippable lignite.

Jan 1, 1972

By Philip C. Good

Preliminary studies showed that direct hydrolysis of H2SiF6 to SiO2 and HF at elevated temperatures was subject to many mechanical difficulties, and that corrosion of construction materials was a serious problem. Elimination of SiO2 from the HF product was generally poor. An alternative procedure, hydrolysis of lime-neutralized H2SiF6 by steam at 950° to 1,100° C, yielded a product very low in SiO2. Condensates containing up to 300 g/1 HF were prepared.

Jan 1, 1968

By M. M. Tilman

As part of ongoing research to improve mine safety, the Bureau of Mines conducted research on the corrosion of friction rock stabilizer steels in five Missouri lead and iron mine waters. Electrochemical corrosion tests, including evaluation of pitting tendency, were performed on two types of high-strength, low-alloy (HSLA) steels and galvanized steel in four Missouri lead mine waters and one Missouri iron mine water. The tests were conducted at in-mine water temperatures in both air-saturated and deaerated waters. Static, weight-loss corrosion tests were also conducted on HSLA steel specimens in the five Missouri mine waters for 2,900-h duration at average in-mine water temperatures and air-dissolved oxygen contents of 6 to 7 ppm. Corrosion rates determined by the weight-loss tests were roughly comparable with rates determined electrochemically in deaerated waters containing 0.3 to 0.5 ppm dissolved oxygen content. Passivation of specimen (nongalvanized) surfaces in air-saturated waters resulted in very low electrochemically deter- mined corrosion rates. Pitting-tendency was generally higher for both HSLA steels in air-saturated waters than in deaerated waters. Galvanized steel generally exhibited higher tendency to pitting in the deaerated waters than in the aerated mine waters.

Jan 1, 1985

By C. H. Fisher

Sulphuric acid of various concentrations has long been used as a reagent in the determination of olefins and aromatics in hydrocarbon oils4 such as gasoline, kerosene, and neutral oils from coal-tar distillates. Despite its long use, however, there is no general agreement as to optimum conditions and concentration of acid, and numerous methods and modifications have been recommended. In most cases, treatment of the neutral oil with 80 to 90 percent sulphuric acid, followed by distillation to the original endpoint to remove olefin polymers, is recommended for the estimation of unsaturated hydrocarbons. The distillate thus obtained is taken as olefin-free oil and used in later stages of the anlysis. Aromatic hydrocarbons generally are determined in the olefin-free oil by suphonation with more concentrated acid (96 to 100 percent and fuming sulphuric acid are recommended), the hydrocarbons not attacked and removed as water-soluble sulphonic acids being considered as saturated hydrocarbons. In some cases the saturates are examined further by differentiating between cyclic (naphthenes) and acyclic hydrocarbons (paraffins), Generally this is achieved by physical methods, although strong sulphuric acid is known to react preferentially with some types of saturated hydrocarbons. It was the purpose of the present work to make a general study of this type of analysis and to investigate the reactions of hydrocarbons under conditions often used in analyses that employ sulphuric acid reagents. Since previous work is not in good agreement, the optimum concentrations of acid for the different stages of the analysis were determined. Several sulphuric acid methods previously recommended and new modifications were compared, two synthetic solutions being used as the reference oil. The results obtained are presented below under separate headings.

Jan 1, 1937

By K. E. Robinson

This study provides an initial indication that mill tailings produced in the Coeur d'Alene Mining District of Idaho can be placed on floodplain areas in a technically acceptable manner without artificial liners and without seriously contaminating the surrounding area. Tests have shown that landfills on these unused areas can result in returning these areas to productive use. The engineering properties of mill tailings permit construction of stable embankments. Designed slope protection inhibits water erosion. Among the environmental considerations in using tailings for landfill construction are the acid and other contamination produced by tailings and wind erosion of exposed tailings surfaces. The initial results indicate that adverse impacts are not as severe as previously thought, and mitigative measures are feasible. Based on the preliminary data, and in accord with existing Federal and State waste management regulations, a conceptual design has been developed for 23 potential landfill sites in the District, which could reclaim 750 acres of floodplain. A cost analysis of landfill construction with mill tailings indicates that the method would be an economically viable means for increasing the valleywide tailings storage capacity, provided construction with slurried tailings is feasible. A Stage H study is proposed to evaluate slurried tailings as a foundation material, as opposed to hauled tailings used in this present study.

Jan 1, 1981

By E. J. Lintner

This paper is one of a series being prepared by the United States Bureau of Mines describing cloy reining, crushing, and grinding methods and costs at various operations throughout the United States. These Toners are designed to disseminate technical information regarding methods used. The cost tabulations represent local operating expenditures only and not total production casts. Although the publication of total production cants might not be advisable in sore instances, yet a knowledge of operating costs is essential to the technical discussion end study of the methods employed. The attention of the reader is specifically coiled to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue. The following report deals specifically with the methods employed by the Clay City Fire Co., Uhrichsville, Tuscarawas County, Ohio.

Jan 1, 1936

By Morton Corn

The U. S. Federal Coal Mine Health and Safety Act of 1969 placed limits on the permissible concentration of airborne respirable coal mine dust. Evidence exists which suggests that the effects on health of respirable coal mine dust may depend on both host factors and dust properties other than concentration. Dust particle size, shape, density, specific surface area and chemical composition are among the dust parameters of interest in an epidemiological investigation of coal workers' pneumoconiosis and coal miner exposure to mine dust. The purpose of this investigation was to develop and demonstrate the feasibility of techniques to determine selected properties of respirable coal mine dust. An approved underground horizontal elutriator which samples air at 36 cfm was designed, fabricated and utilized in this study to collect respirable coal mine dust in three mines representing the Pittsburgh, Lower Freeport and Lower Kittanning coal seams. Analytical procedures for measurement of respirable dust sample particle size, density, random projected area, total surface area and chemical composition are presented. Results of analyses of three samples collected in each mine are presented. Up to five full work shifts of sampling were required to accumulate approximately five grams of respirable coal mine dust in each sample. Statistical tests were applied to determine the significance of differences between properties of dust samples collected in the same mine and between arithmetic mean values of dust properties representing three samples collected in each mine. A comparison was also made between

Jan 1, 1972

By Wallace W. Roepke

Four bit designs, two conical and two radial, were tested in coal against a 60° conical reference bit to obtain data on orthogonal cutting forces and primary respirable dust generation. One conical and one radial design were modified by the Bureau of Mines for these tests. Results were mixed: One radial bit used substantially lower overall cutting forces and specific energy than the other bits and was the only cutter lower on energy and most forces than the standard 60° bit. How-ever, it generated more specific and total dust than any other bit. The four bits were also tested for incendivity, with a 90° plumb-bob bit as the reference. The frictional ignition tests were designed to simulate both trimming top rock and cutting such rock during advance on-sump. Results of these tests were also mixed. The radial bits were substantially less incendive than the reference bit and caused no ignitions in either top trimming or sump modes. Only the modified mushroom-tipped conical bit caused ignitions. Bits similar to this modified design should not be used on drum-type miners in gassy mine areas; in-stead, the other types of bits tested should be used to reduce ignition potential to a minimum.

Jan 1, 1983

By B. W. Jong

The Bureau of Mines studied reinforcement of sulfur concretes using glass, polyester, and aramid fibers. The objective of this research was to determine the feasibility of fiber-reinforcing the sulfur concrete to enhance the flexural properties. Optimum fiber sulfur concrete compositions were formulated with a cement-to-fiber ratio of 9.0:1 for glass-fiber and polyester-fiber sulfur concretes and 12.1:1 for aramid-fiber sulfur concretes. Test samples were prepared using techniques developed by the Bureau of Mines. Flexural strength values of up to 50 pct of compressive strength values were achieved with fiber additions. With non-fiber-reinforced sulfur concrete, the values ranged up to 20 pct. The impact strength and fracture toughness of sulfur concretes were increased sig-nificantly by reinforcement with glass or with aramid fiber and were adversely affected by use of polyester fiber. Strain tolerance was doubled and failure mode was shifted from catastrophic to noncatastrophic type by adding glass fiber. The glass-fiber and aramid-fiber sulfur concretes are resistant to acid corrosion and have proved durable in freeze-thaw cycles. This laboratory and field evaluation has shown that fiber reinforcement of sulfur concrete is feasible and that it enhances the flexural properties.

Jan 1, 1985

By Joseph J. Wallace

1. The investigation shows that there are 2 coal beds of major importance in Letcher County from the standpoint of present production - Upper Elkhorn No, 3 and Fire Clay - and 5 beds of minor importance - Whitesburg, Flag, Haddix, Elkhorn Leader, and Amburgy, The Upper Elkhorn No. 3 and Fire Clay beds contain the largest remaining known reserves. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and on 1,600 tons per acre-foot of coal in place, are estimated at 1,353 million short tons as of January 1, 1952. Of this total, 1,056 million short tons ere in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bad characteristics are too meager to make an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1953

By N. S. Dalal, B. Jafari, F. H. Y. Green, M. Petersen, V. Vallyathan

"Stable coal radicals (SCRs) were detected by electron spin resonance (ESR) spectroscopy in the lung tissue of autopsied coal miners. The SCR concentrations were measured in the lung tissues from 98 coal miners with and without (a) coal workers' pneumoconiosis (CWP), (b) cancer, and (c) a history of cigarette smoking. Concentrations of SCRs were also determined in the lungs of nonminer controls. The SCR concentration was related to longer mining tenure, CWP disease severity, lung cancer, and cigarette smoking. The mean concentration of SCRs in the lung tissues of miners with 30 ± 1.4 y of coal mining exposure was 5.3 ± 1.3 x 10"" spins/g versus controls who had a nondetec¬table level (< 10 15 spins/g). An increase in disease severity was accompanied by a progressive increase in SCR concentration. A SCR concentration of 4.8 ± 0.7 x 10"" spins/g was found for simple CWP (with moderate coal macules) versus 7.8 ± 4.6 spins/g lung tissue for complicated CWP (with progressive massive fibrosis). Significantly higher (i.e., 10 x 10"") concentrations of SCR in the coal miners' lung tissues were associated with an exposure history in the anthracite regions of northeastern Pennsylvania. These results in¬dicate a possible role for SCRs in the disease process. Furthermore, ESR appears to be an adequate methodology for the quantitation of coal dust retained in the lung and for distinguishing exposures to anthracite and/or bituminous coal.THE PREVALENCE AND SEVERITY of coal workers' pneumoconiosis (CWP) differ markedly between geographic locations, mines, and coal fields irrespective of comparable levels of exposure to coal mine dust These differences cannot be fully explained by the presence of silica and other minerals in the coal mine dust.' Rank of coal is also an important factor in the pathogenesis of CWP. Equally important is that the prevalence of CWP decreases from east to west in the United States,' and South Wales miners develop more severe CWP than miners in Scotland.' However, there are conflicting reports that cast uncertainty on the influence of rank of coal in the development of CWP."" These problems are complicated but will be solved as new technology emerges and as more is learned about the disease process."

Mar 1, 1992

By F. R. Lee

[THE Bureau of Mines was established in July 1910 to conduct research and to Establish standards for mining equipment and practices which would conserve human life, natural resources, and property in the mineral industries. Several lists of equipment approved by the Bureau as permissible for use in gassy coal mines have a been issued since then. The lists covering all approved equipment except breathing apparatus and explosive have been consolidated info two publications: Bulletin 543, Permissible Equipment Approved to January 1, 1953, and Information Circular 5220, Permissible Mine Equipment Approved By The Bureau of Mines During 1953-62. The purpose of this publication is to supplement Bulletin 543 kind Information Circular 8220 with a listing of permissible equipment approved during 1963 and 1964. The schedules (standards) under which equipment listed herein have born approved are as follows (titles and dates of approval and revision are given in footnotes): Schedule 2F,3 schedule 6D,4 schedule 7C,5 schedule 8C,6 schedule 9B,7 schedule 10C,8 schedule 12D,9 schedule 22,10 schedule 24,11 schedule 25B,12 schedule 28,13 schedule 29A,14 schedule 30,15 and schedule 31.16]

Jan 1, 1966

By Verne E. Hooker

The Bureau of Mines conducted a preliminary investigation to determine the state of stress in crystalline rock outcrops near Atlanta, Ga. The secondary principal stresses in a horizontal plane near the surface are compressive and are 500 to 3,000 psi. The maximum compressive stress is northeast-southwest in the Stone Mountain-Lithonia district but changes to northwest-southeast near Douglasville. The elastic constants were determined from data obtained by static and dynamic laboratory methods and in situ velocity measurements. Results show Young&apos;s modulus to be dependent upon both stress level and anisotropy in the rock. Average secant moduli obtained from triaxial tests were used to compute the applied stress from borehole deformation measurements.

Jan 1, 1966

By Charles L. Kusik

As part of an effort to establish the extent of the domestic chromium supply that could be exploited in case of adverse changes in international chromium production and trading patterns, a two-part study was conducted for the Bureau of Mines, to assess the domestic availability of critical metals in scrap containing significant amounts of chromium. This report describes the part of the study that deals with wrought stainless steels and heat-resisting alloys. Data were collected on types of scrap, sources, quantities, and ultimate disposition, leading to the conclusion that In 1917 about 62,000 tons of contained chromium was unrecycled. Unrecovered obsolete stainless steel scrap accounts for most of these uncollected chromium values. Error margins in the amount of uncollected scrap are estimated to be 10 to 20 percent.

Jan 1, 1980

As part of a continuing program of evaluating the Nation&apos;s crude-oil resource, this report presents information pertaining to resource, primary reserve, and potential waterflood reserve for 3,209 selected reservoirs contained in 24 oil-producing States, as of January 1, 1968. To that date the selected reservoirs had not been subjected to pressure-maintenance or secondary-recovery operations. These reservoirs also met the following parameters: (1) a minimum of five oil-producing wells on January 1, 1968, (2) a minimum of 50 acres areal extent, (3) a minimum of 50,000 bbl of oil ultimate primary recovery, and (4) the principal reservoir energy was other than active water encroachment. The selected 3,209 reservoirs produced 527 million bbl of oil in 1967, about 17 pct of U.S, total production. Primary oil reserve was 4,983 million stb; in addition, there was 6,043 million stb of potential water- flood oil reserve. Oil resource in the selected reservoirs was 59,547 million stb. A brief history and outlook of waterflooding are presented for each State. Depth and producing rate statistics and geologic distributions of production, resource, reserve, and potential waterflood reserve for the selected reservoirs are presented by States in the appendix. Also included in the appendix are description, history, and technique modifications of waterflooding, and a preliminary cost estimate of a closed-system water-injection project.

Jan 1, 1970

By George Quackenbos

The principal objective of this Program is the design, fabrication and testing of an Environmental System for operation in underground mines, to assess the effect of various mining systems on the contaminant levels near the mine face and within return airways. In order to determine the effect on airborne contamination in mines resulting from the development of new mining techniques, equipment and control systems, a Comprehensive Monitoring System is required to assess such contamination levels at critical and strategic locations and relate this information with ventilation parameters. The three variables to be sensed on a continuous basis are airborne dust concentration, methane concentration and ventilation air velocity. Each Monitoring Station will consist of a self-contained unit containing a power source and sensors to monitor the three above mentioned parameters. Ruggedness, reliability, ease &apos;of operation and intrinsic safety are important design objectives. Data gathered by each Monitoring Station will be fed to a Central Data Acquisition System by means of a portable transfer unit.

Jan 1, 1982