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By Gilbert M. Farrior

Tests of resistance to molten metals , to oxidation at elevated temperatures , and to various chemical reagents were made for a series of compositions in the TiB₂ - CrB₂ subsystem . In reaction with molten metals , there was no noticeable difference in reaction of the various compositions in the ( Ti , Cr ) B₂ series . The oxidation tests were ( 1 ) a rising - temperature test in which the specimen temperature was increased 4° per minute to 1,200 ° C and ( 2 ) a constanttemperature test in which the specimen temperature was held constant at 1,000 ° C. Compositions near Tio.6 Cro.4 B2 had the best oxidation resistance . Ti。.6 The chromium- rich alloys showed marked superiority to the titanium- rich alloys in resistance to corrosion by the chemical agents investigated . The chemical reagents used were sulfuric , nitric , and hydrochloric acids and sodium hydroxide of different concentrations .

Jan 1, 1964

By F. D. Everett

The Burgin shaft of Bear Creek Mining Co. near Eureka, Utah, was sunk during 1956 and 1957 as part of an exploratory program, searching for lead, zinc, copper, silver, and gold ore bodies hidden from the surface by several hundred feet of volcanic rocks. This paper describes the sinking methods and operating practices of Centennial Development Co., contracting firm for Bear Creek Mining Co., in sinking a 3-compartment vertical shaft 1,100 feet. The operation featured the Cryderman positive-action, clam-type shaft mucker. The shaft was completed in 142 days by a shaft crew of 10 men and a top force of 10 men, including supervision.

Jan 1, 1959

By J. B. F. Champlin

The continuing development of the nuclear industry in the United States requires a program of waste disposal that insures against the release of large amounts of radioactivity to the environment. This paper describes research on one proposed means of disposal of this waste, that of injection into geologic formations at depth. Nuclear production plant wastes were simulated and injected into samples of sedimentary rock obtained from outcrops, quarries, and deep wells. Changes in the chemical and physical characteristics of the rocks caused by the interaction of ions and suspended particles in the waste solutions with the cementing material and claylike particles in the rock are discussed. Laboratory tests show that nuclear wastes can be injected into many natural porous, permeable geologic formations. Injectivity can be maintained over a longer period by monitoring the ionic balance and particle-size distribution of waste streams. The combination of permeability and porosity with low cation-retention capacity, as exhibited by most sandstones, would satisfy the engineering requirements for the subsurface disposal of nuclear waste. Shales and clays with their low permeability and high cation-retention capacity would make excellent confining formations. The amount of cation retained by sedimentary rocks increases with increasing valence or concentration of the cation or decreasing brine concentration. The use of rock cores as model reservoirs had proved successful in determining some of the parameters that need to be considered in full-scale field disposal of wastes.

Jan 1, 1967

By James R. Boyle

The value of Alabama's nonfuel mineral production in 1980 was $328.6 million, a decrease of $7.8 million from 1979. Cement, crushed stone, lime, clays, and sand and gravel continued as the major commodities produced. Alabama led the Nation in the production of crushed marble; was second in bauxite; third in native asphalt, ferroalloys, kaolin, and oyster shell; fourth in dimension marble, masonry cement, and bentonite; and fifth in fire clay and lime. Alabama ranked in the top 20 States in total value of non-metallic minerals produced. Adverse economic conditions in the construction and metals industries impacted on the minerals industry in Alabama. Mineral producers supplying raw or finished materials to these industries experienced periodic reductions in sales during the year. Unit price increases did not keep up with inflation.

Jan 1, 1982

By Ralph H. Whaite

The Bureau of Mines program for microfilming maps of abandoned mines in the Pennsylvania anthracite region is described. A catalog of the maps that have been microfilmed in the Eastern Middle anthracite field--the first area to be covered in the program--is presented. Additional catalogs will be published as significant mining areas are completed.

Dec 1, 1964

By Beatrice Lukens, David Schlain, John D. Prater

"The electrolytic manganese process4/ developed by the Bureau of Mines involves the electrolysis of a solution of manganese sulfate and ammonium sulfate in a diaphragm-type cell. Metallic manganese is deposited on the cathodes, and sulfuric acid is produced at the anodes. The spent electrolyte contains, in addition to the sulfuric acid, approximately 40 percent of the manganese sulfate and most of the ammonium sulfate originally present in the feed solution. This spent solution is used to leach fresh ore that has previously been subjected to a reducing roast. The resulting leach liquor is purified and returned to the cell.Manganese of very high purity is produced by the electrolytic process. The properties of this metal are so different from those of the best grade of manganese that can be made by any other commercially feasible process that it is virtually a new material. Electrolytic manganese has been used in the preparation of new high-manganese alloys with valuable properties.3/ and further developments are to be expected. The electrolytic manganese process not only results in a product of superior qualities, but is applicable to large tonnages of domestic ores that are unsuitable for direct use in producing ferromanganese.The future industrial use of electrolytic manganese is of course, related to its cost. Decreases in the cost of production will lead to wider use of the metal; conversely, increases in the volume of production made possible by greater demand will bring further .decreases in cost."

May 1, 1946

By X. Shi, K. S. Kaspnak

"The generation of free radicals from reactions of nickel (Il)-thiol complexes with molecular oxygen and model lipid hydroperoxides was investigated by electron spin resonance (ESR) utilizing 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a spin trap. Incubation of nickel (II) [Ni(II)) with cysteine in an aerobic environment generated hydroxyl (·OH) radical, which then reacted with cysteine to generate a carbon-centered alkyl ( · R) radical. Radical generation was inhibited under a nitrogen atmosphere. Model lipid hydroperoxides, cumene hydroperoxide, and I-butyl hydroperoxide enhanced the yield of these radicals and also generated an alkoxyl (·OR) radical. Radical yield decreased by approximately half under a nitrogen atmosphere. Although histidine did not cause radical formation in the reaction between Ni(II) and cumene hydroperoxide under aerobic conditions, the addition of histidine to a mixture containing Ni(ll), cysteine, and cumene hydroperoxide under the same experimental conditions increased the yield of · R radical but lowered the yield of ·OR and ·OH radical adducts. It thus appears that histidine caused the ·OH attack to be more site-specific. Similar results were obtained utilizing 1-butyl hydroperoxide. Penicillamine or N-acetylcysteine yielded similar results except that under aerobic conditions, reaction between Ni(ll) and N-acetylcysteine without hydroperoxide did not generate a significant concentration of free radicals. Under the same experimental conditions, cystine did not generate any detectable free radicals, suggesting an important role of the -SH group in Ni(II)-mediated free radical generation. The results indicate that free radical generation from the reaction of Ni(Il)-thiol complexes and molecular oxygen, and/or lipid hydroperoxides, may play an important role in the mechanism(s) of Ni(II) toxicity and carcinogenesis. INTRODUCTIONWhile nickel is a well-recognized carcinogen [l, 2]. the underlying biochemical mechanisms remain unclear (3, 4). Recent studies suggest that these mechanisms may involve oxidative DNA damage through free radicals, especially the hydroxyl (•OH) radical [5-13]. The mechanisms of nickel carcinogenicity and toxicity may also involve lipid peroxidation [14-21]. Unlike ferrous ion [Fe(II)], the Ni(II) cation itself does not directly react with 02, H2O2, or lipid hydroperoxides to generate free radicals [12, 21]. However, it has been reported that Ni(II) complexes with certain synthetic oligopeptides, e.g., tetraglycine or glycylglycylhistidine, make Ni(II) reactive with 02. This reaction results in transitory formation of Ni(III) and degradation of the organic ligand via free radical reactions [22]. Such Ni(II)-peptide complexes are also capable of reacting with H2O2 to produce oxygen free radicals [11, 12]. Although the cellular environ¬ment may not contain these particular peptide ligands that are known to render Ni(II) redox active in vitro, it does contain a variety of oligopeptides that are capable of forming Ni(II) complexes at physiological pH, and thus may facilitate Ni(II) redox activity in vivo. These oligopeptides include glutathione (y-L glutamylycysteinylglycine), carnosine (homocarnosine (y aminobutyryl-L-histidine), and anserine ( B-alany1-3-methyl-L-histidine)."

Nov 1, 1995

By J. V. Batty

The Bureau of Mines devised techniques involving the use of beta-and gamma-ray-emitting radioisotopes and successfully adapted these techniques to the density of mineralized flotation froths) the rate of flow of finely ground ore pulps) and the residence time of pulps in processing circuits. Specifically, the water and mineral loads of flotation froths were continuously measured by determining the proportion of a constant-strength beam of beta rays that was absorbed by the froth column. Continuous measurement of the rate of flow of an ore pulp was accomplished by measuring the changing width of a free-falling stream of the pulp with a collimated beam of beta rays. The residence time of solids in conditioning and resin-in-pulp circuits was accurately measured by following the progress through these circuits of a portion of the pulp that had been tagged with the gamma-emitting Ag110 radioisotope.

Jan 1, 1966

By Richard W. Lewis, Lloyd Carpenter

The objective of the investigation was to determine spectrochemically 19 elements in the general range of 0.5 to 1,000 ppm in high - purity hafnium and its compounds . Samples were converted thermally to hafnium dioxide , mixed with buffer - carrier - internal standards , and excited by a dc arc . Spectra were recorded on photographic plates . Transmittance values were recorded densitometrically and converted to relative - intensity ratios . Four groups of standards were used to establish analytical curves from which the concentrations of impurities were obtained . Average precision of the method was 14.2 percent relative standard deviation , and relative error was 4.2 percent .

Jan 1, 1964

By H. A. Dierks

The work and costs involved in controlling three large fires in abandoned mines in the anthracite region of Pennsylvania are presented in detail. The work was done under authority of Public Law 89-4. Three basic control techniques were successfully employed by the Bureau of Mines: (1) forming underground fire-containing barriers by systematically flushing incombustible material into mine voids, (2) excavating an isolation trench around the fire area, and (3) complete excavation of hot and burning material in the fire area. When methods 2 and 3 were used, the excavations were subsequently back- filled with incombustible material. Preliminary location of fire perimeters by the standard use of patterned 6- and 8-inch-diameter boreholes is discussed. Investigations into air-borne infrared scanning, shallow subsurface thermal anomalies, and the use of helium to trace the movement of mine air currents are covered. Although they are costly and time consuming, boreholes have proven to be the most efficient means to date of obtaining necessary subsurface fire data. Infrared scanning was ineffective in delineating fires under more than 30 feet of cover. Helium-tracing was shown to have a good potential for determining possible hazards to adjacent residential areas from traveling mine fire gases.

Jan 1, 1971

By F. N. Kissell, C. D. Litton

Abstract-This study predicts the level of smoke that miners might meet while trying to escape a coal mine fire and describes how smoke would impede their safe escape. For this study, the authors assumed that miners exit through an escapeway adjacent to the burning entry, that some air would leak from the burning entry to the escapeway. The following conclusions were made: • A very low amount of air leakage to the escapeway can produce a critical level of visual obscurity from smoke. This shows that intake airways may be as susceptible to smoke visibility problems as return airways. • This critical level of smoke obscurity is reached much before a critical level of carbon monoxide is reached. • Small fires can cause a severe sensory irritation that further limits vision. Thus, reliable eye protection is very important. These results show that methods to guide miners through dense smoke will contribute greatly to saving lives during mine fires.

By Ralph H. Whaite

The Bureau of Mines program for microfilming maps of abandoned mines in the Pennsylvania anthracite region is described. A catalog of the maps that have been microfilmed in the Eastern Middle anthracite field--the first area to be covered in the program--is presented. Additional catalogs will be published as significant mining areas are completed.

Jan 1, 1965

By Ralph H. Whaite

The Bureau of Mines program for microfilming maps of abandoned mines in the Pennsylvania anthracite region is described. A catalog of the maps that have been microfilmed in the Eastern Middle anthracite field--the first area to be covered in the program--is presented. Additional catalogs will be published as significant mining areas are completed.

Jan 1, 1965

By W. H. Tomlinson

One of the more important functions of the Federal Bureau of Mines is conservation of the life and health of employees of the mineral and allied industries. Since its very beginning the Bureau has encouraged competition between mine rescue and first-aid teams as a means of stimulating interest in safety and accident-prevention work. In addition to sponsoring competition on a national and international scale during the past 45 years, the Bureau has also assisted State mining departments, mining companies, and mining organizations in holding State, district, company, and other local meets. This assistance includes providing instructors to train teams, judges, and other contest officials. The Bureau has also furnished problems and outlines for working them, judges I discount sheets (scorecards), contest rules, and problem judges. In fact, Bureau representatives participate in nearly all State, district, and company contests and have bad complete charge of some contests.

Jan 1, 1956

By M. R. Geer

Full-seam mining with continuous mining machines in dirty coal beds may increase loss of coal in the washery refuse. At one mine mentioned in this report the loss of salable coal was increased sixfold. Cleaning trials were made on three samples of jig refuse in a dense-medium pilot plant to demonstrate the application of this process to the recovery of coal from waste. These tests demonstrated that coal could be separated from impurity with the same degree of sharpness obtained in treating raw coal by dense medium. However, the recovery efficiency achieved in treating refuse averaged distinctly lower than that possible with raw coal because of the greater proportion of intermediate-density material in the feed and the lower yield of clean coal.

Jan 1, 1955

By R. L. Grant

The principal official test performed by the Bureau of Mines to determine the permissibility of coal-mine explosives, commonly referred to as the gallery test, has been in use at the Bruceton station for many years (2, 16).4/ In this test the explosive under study is loaded into the borehole of a steel cannon and fired into a flammable mixture of natural gas and air or natural gas, air, and coal dust. To meet the requirements for permissibility, the explosive must not ignite the gas mixture under the conditions of the test. There is little doubt that these tests have succeeded in the main objective, namely, to screen the relatively safe from the relatively hazardous explosives. It has been generally conceded that adoption of permissible explosives by the coal-mining industry in the United States has substantially reduced the frequency of disastrous underground explosions caused by blasting. In recent years, however, research workers planning programs for improving the safety of coal-mine explosives have felt the growing need of a more quantitative method for measuring the incendivity of explosives based on a better understanding of the role of the important variables in the gallery tests, Accordingly, it was decided to apply certain statistical methods and techniques to the gallery test to develop it into a more precise tool for evaluating permissible explosives. One of the first and more important methods applied for this purpose was the up-and-down technique (6,7,17), It was demonstrated (14,15) that the weight of the explosive charge directly affects the ignition probability of the natural gas-air atmosphere and that the curve of ignition probability versus charge weight is a cumulative normal curve. Following these experiments, a program, still in progress, was set up to study how the addition of sodium chloride to various permissible-type ex-plosives affects their incendivity. This program resulted in 3,294 shots,

Jan 1, 1961

By Steven J. Page

Since 1982 standard calibration materials recommended for respirable crystalline silica analysis by the Mine Safety and Health Administration (MSHA) P7 Infrared Method and the National Institute for Occupational Safety and Health (NIOSH) X-ray Diffraction (XRD) Analytical Method 7500 have undergone minor changes in size distribution. However, a critical assumption has been made that the crystalline silica in ambient mine atmosphere respirable dust samples has also remained essentially unchanged in particle size distribution. The objective of this work, therefore, is to compare recent particle size distributions of underground coal mine dust and the silica component of these dusts with estimated aerodynamic particle size distributions of calibration standard materials MIN-U-SIL 5, Berkeley 5, and SRM 1878 used by two crystalline silica analysis techniques. This work provides resolution to a previously reported discrepancy involving the proper sample dilution for the particle sizing method used. Dust impactor sampling data for various locations in 13 underground coal mines were collected between 1991 and 1998 and analyzed for the respirable mass median aerodynamic diameters. The data suggest that the MSHA P7 Method will underestimate the silica content of the sample by at most 8.5 % in the median size range of 0.9–3.6 µm and that it is unlikely one would obtain any significant error in the MSHA P7 Method analysis when the method uses Berkeley 5, MIN-U-SIL 5, or SRM 1878 as a calibration standard material. The results suggest that the NIOSH Analytical Method 7500 would be more appropriate for a dust sample that is representative of the total (no cyclone classifier) rather than the respirable airborne dust, particularly since the mass fraction in the size range below 4 µm is usually a small percentage of the total airborne dust mass. However, the NIOSH Analytical Method 7500 is likely to underestimate the silica content of an airborne respirable dust sample by only 5–10 %. The results of this study also suggest that any changes that may have occurred in the median respirable size of airborne coal mine dust are not significant enough to cause any appreciable error in the current methods used for respirable crystalline silica analysis.

Aug 3, 2005

By Glen C. Ware

The Bureau of Mines determined the factors involved in the corrosion of starting sheets used in the production of electrolytic zinc with the ultimate purpose of adapting zinc starting sheets to commercial practice . Under present practice , zinc is electrodeposited on aluminum cathodes and subsequently stripped for melting . The use of zinc instead of aluminum would eliminate the need to strip the deposit , thereby reducing the cost of handling and melting it , but zinc has not been suitable because it was too vulnerable to the corrosive attack of the electrolyte . Serious attack was found to be limited to the areas of the cathodes situated immediately above the surface of the electrolyte and to re - entrant corners . It was possible to avoid solution - level corrosion by immersing the starting sheets completely , exposing only a relatively heavy suspension member to solution - level attack . Zinc starting sheets could be made as reliable as aluminum and could be continued in residence for periods up to 39 days . Periods as long as a week were feasible under conditions similar to those found in commercial practice . A test of zirconium as a starting - sheet material showed that it promoted corrosion of the deposit to a lesser extent than aluminum and that the deposit adhered less tenaciously . These two properties lend themselves to the development of ways to strip deposits mechanically from zirconium starting sheets . Titanium was unsuitable for use as a starting - sheet material .

Jan 1, 1963

By Richard L. Sanford

This report summarizes the results of the development of a Directory of Computer Programs Applicable to U.S. Mining Practices and Problems. The Directory includes a sampling of computer usage in operating and manufacturing companies, consulting firms, computer companies, research organizations, universities, and various U.S. government agencies. References to computer applications throughout the mining industry are presented as well as comments on the availability of programs to interested organizations or individuals.

Jan 1, 1977

By W. D. Mcmillan

Preliminary examination of the north-central Kansas clay deposits was made by the junior author during March 1943. He was accompanied by Norman Plummer, ceramist of the State Geological Survey of Kansas. Three areas Nacre selected for further investigation. Detailed field investigation by the Bureau, consisting of hand auger drilling, trenching, anti. test pitting to obtain representative samples of the clays was carried on from April to June 1943. Field .work was under the direction of Edgar B. Butte and Richard L. Schumacher, former Bureau of Mines engineers. The samples taken were analyzed at the Bureau of Mines laboratory at Rolla, Mo. Factual data obtained from the field investigation and laboratory work are set forth in this report.

Jan 1, 1948