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By D. Bienstock, R. C. Kurtzrock, E. R. Bauer, J. H. Field

To remove hydrocarbons and carbon monoxide in automotive exhaust by oxidation , a catalyst of 4.2 percent Uз Og , 1.7 percent Cr₂ 0 , and 1.7 percent CuO supported on 1 /8 - inch y- alumina spheres was tested in a reactor in place of the muffler of a 1 / 2 - ton truck . Tests were made with both nonleaded and leaded gasolines . With the engine at operating temperature , tests were made with the engine idling and with the vehicle cruising at 30 mph . Auxiliary air was added to maintain an oxygen concentration of 3 to 4 percent in the gas leaving the catalytic reactor . The vehicle was operated for 83 hours (about 60 percent of the time with the engine idling ) and 525 miles with nonleaded gasoline . Conversions of 98 percent of the hydrocarbons and 100 percent of the carbon monoxide were achieved with the engine idling and with 7,000 ppm carbon atoms and 4- percent carbon monoxide in the feed to the reactor . Hydrocarbon conversions of 75 percent were obtained at cruising speeds of 30 mph with a feed of 1,700 ppm carbon atoms ; the carbon monoxide concentration was less than 0.3 percent in the feed and was unchanged in passage through the reactor . Identical activity was obtained initially in switching to a gasoline containing 1.9 ml tetraethyl lead (TEL) per gallon . However, there was a gradual loss in activity thereafter . Conversions in tests with the engine idling about 50 percent of the time , had decreased by 23 percent for the hydrocarbons and by 25 percent for the carbon monoxide from their initial values after 122 hours and 1,300 miles of operation with leaded gasoline . The levels of radioactive materials in the exhaust of the reactor and the radiation in the vehicle were negligible .

Jan 1, 1963

By C. M. Harrer

This paper describes the location, features, qualities, extent, and potential of iron occurrences and some associative resources -limestone and dolomite, coal, petroleum and natural gas, power, and water - in New Mexico. Reconnaissance investigations were made of 118 iron occurrences to deter-mine their extent, attitude, and potential; character samples were analyzed to determine their quality and impurities; and pioneer metallurgical investigations were made on character samples to present their metallurgical problems. Some factors influencing past and potential iron markets are discussed. The most abundant iron minerals are magnetite and hematite. The higher grade deposits are extensive contact-metamorphic and pyrometasomatic replacements in calcareous Paleozoic rocks associated with intrusives. Low-grade deposits of considerable potential are the extensive Cambrian oolitic hematites of sedimentary origin and the Precambrian magnetite-hematite taconite iron formation. Iron occurs also as extensive colluvial and alluvial concentrations. A wide variety of accessory elements are indicated and these pose metallurgical and economic problems.

Jan 1, 1963

By Jarrell C. Grout

The Bureau of Mines has developed a computer program for use in solving nonlinear regression problems. The program is written in a general form so that, regardless of the functional relationship, the unknown parameters may be evaluated by either the Gauss-Newton or the Newton-Raphson methods of iteration. Variances and covariances of the parameters, as derived from the law for the propagation of errors, are also determined.

Jan 1, 1969

By D. Harrington, M. W. Von Bernewitz

"Introduction In studying the mine disaster files of the Bureau of Mires for preparation of a bulletin on coal-mine explosions, a table was compiled covering various features of fan installations and the handling of air currents at the time of and after the disasters. As a sidelight on this discussion, there was tabulated the loss of life and number of men injured.Discussion of collected dataOf the 164 disasters tabulated, 148 were explosions, 14 were fires, and 2 involved both fire and explosion. The total loss of life was 4,158 and 412 were injured. There were 145 disasters in bituminous coal mines, 13 in anthratice mines, 2 in lignite mines, 1 in a cannel coal nine, and 3 in metal mines. By States, 35 took place in Pennsylvania; 17 in West Virginia; 16 in Oklahoma and Alabama; 15 in. Kansas and Illinois; 12 in Indiana; 7 in Colorado; 6 in Kentucky; 3 each in Ohio Tennessee and Wyoming; 2 each in Arkansas, Montana, Washington, Virginia, New Mexico and Utah and 1 each in Iowa, Missouri, Maryland, and California."

Sep 1, 1924

By V. F. Parry

[Approximatel~r 7-1/2 illion tOlls of subb1tnminous coals are mined an-nuall in Colorado, Wyo~ing, and Montana, of which 50 percent probably reaches dome ,-tic conswno:os. r:L'he moi s t'_re of the se subbi t1.Uninous coal sis high, averae;:t.:ug about 25 :!,)ercent \-Then they are :nined. T'ne coals are non-caking d ~~ack to a vari ble degree when exposed to nornal atmospheric conditions. ~hey a~e gpod domestic fuels, are considered to be smokeless in most furn~ces, and have been used. f, r f!1an: y ars in hand-fired domestic furnaces in hich tnc practice i~ to e~ploy large lureps for efficient com-]

Jan 1, 1941

By Guy E. Dent, Hugo E. Kuehn

"SUMMARYFor making a comparison of magnetic surveys measured from the ground and from the air, Worcester County, Maryland, was chosen as a proving ground. Vertical magnetic intensities were observed on the ground, and total magnetic intensities were observed from the air. A comparison of the two magnetic maps reveals similar large magnetic features, but these are displaced in some instances by distances greater than a mile. Magnetic terrane in the two charts is of the same type but often differs greatly in respective characteristic features.The sacrifices in accuracy that may be expected from the use of different systems of diurnal magnetic corrections on ground observations constitute a part of this report.INTRODUCTIONThe value of magnetic surveys for gaining information concerning the crystalline basement is recognized increasingly. That this topography is often reflected to a major degree in the overlying sediments with certain offsetting is well understood. Even where such sediments are deep, the surface topography of upper formations often reflects this bedrock topography to a certain degree."

May 1, 1947

By J. L. Kohler

The final report for Phase II of Bureau of Hines Contract J0134025 concerns the research and development of sensitive ground-fault relays for dc utilization systems in mining. Sensitive relaying employs very low pickup levels such that, when used in conjunction with very high resistance grounding, the exposure of a human to ventricular fibrillation is significantly reduced. To delineate the desired relay characteristics, the report begins by reviewing previous research in this area. A theory for the saturable transformer used to sense the fault current is presented. The design of the ground fault relay is described in sufficient detail that it may be duplicated. Test procedures and results are given. Finally, conclusions and recommendations related to Phase II are presented.

Jan 1, 1986

By James F. Devine

The radial, vertical, and transverse components of particle velocity were recorded by Bureau of Mines investigators along gage arrays extending in one or two directions for 145 to 3,170 feet at five quarries. Of the 39 quarry blasts, 12 were instantaneous blasts, 5 were of the one hole per delay type, using millisecond delayed caps, and 22 were multiple hole per delay type employing millisecond delay detonating fuse connectors. Charge weight per hole ranged from 8 to 1,500 pounds, and the charge weight per delay interval, including the instantaneous blasts, ranged from 25 to 4,620 pounds.

Jan 1, 1966

By C. M. Harrer

This paper describes the location, features, qualities, extent, and potential of iron occurrences and some associative resources - limestone and dolomite, coal, petroleum and natural gas, power, and water - in New Mexico. Reconnaissance investigations were made of 118 iron occurrences to determine their extent, attitude, and potential; character samples were analyzed to determine their quality and impurities; and pioneer metallurgical investigations were made on character samples to present their metallurgical problems. Some factors influencing past and potential iron markets are discussed. The most abundant iron minerals are magnetite and hematite, The higher grade deposits are extensive contact-metamorphic and pyrometasomatic replacements in calcareous Paleozoic rocks associated with intrusives. Low-grade deposits of considerable potential are the extensive Cambrian oolitic hematites of sedimentary origin and the Precambrian magnetite-hematite taconite iron formation. Iron occurs also as extensive colluvial and alluvial concentrations. A wide variety of accessory elements are indicated and these pose metallurgical and economic problems.

Jan 1, 1963

By E. P. Youngman

The rapidly growing demand for titanium pigments has aroused new interest in actual and potential sources of supply of titanium- bearing ores , which only a comparatively few years ago were almost unmarketable . This paper , which supplements a general circular entitled " Titanium" ( Information Circular 6365 ) , represents a summary of current trade literature and Government reports , together with some hitherto unpublished material that has accumulated in the files of the Bureau of Mines . The purpose of this pamphlet is simply to indicate the commercial possibilities of the deposits , and the discussion is confined almost entirely to the three commercial ores , ilmenite , rutile , and magnetite ( titaniferous iron ore ) .

Oct 1, 1930

The Federal Coal Mine Health and Safety Act of 1969 requires that each operator of a coal mine shall take accurate samples of the amount of respirable dust in the mine atmosphere to which each miner is exposed, a measure designed to prevent the development of coal workers' pneumoconiosis. This textbook manual is used in the training of personnel to operate respirable dust sampling devices and to conduct sampling programs. It contains the portions of the act applicable to respirable dust standards, the procedures to be followed to insure compliance with Federal regulations, and descriptions of sampling devices.

Jan 1, 1971

By K. L. Paciorek

The aim of the present study was to determine the thermal oxidative behavior of materials used in coal mines, with emphasis on the type and relative concentration of the products, in particular the toxic species formed. To supplement this work and to gain understanding as to the type of products possibly formed and also to assess the limitations and advantages of the various analytical methods used a literature survey of the past investigations performed on the compositions of direct interest to the subject program was conducted. The compositions thus covered were cellulose, polyvinyl chloride, neoprene, urethanes, polyamides, polyesters, polyethylene, epoxy, phenoxy, urea-formaldehyde and melamine formaldehyde resins. The results of this review are compiled in the Appendix. The experimental work consisted of thermal oxidative degradation of 36 materials and 4 composites using a stagnation burner apparatus developed in these laboratories which affords a dynamic system approximating somewhat the conditions encountered in underground coal mines. This technique as employed during this program gave only the relative product concentration at specific periods of the decomposition process, The advantage of this approach is that in this manner screening of materials can be accomplished in conjunction with some assessment of the decomposition rate as influenced by temperature and material composition. Limited static tests were performed using a sealed tube method. The materials studied were grouped according to their compositions. The following were the main groups: (a) polyvinyl chloride-containing materials, (b) neoprene compositions, (c) rigid foams (urethanes, isocyanates), (d) miscellaneous materials (including jute, fiberglass, polyethylene and some articles of unknown composition), (e) coal and fluids (phosphate esters, organic esters, oil-water emulsions), and finally (J) composites. The latter comprised a mixture of a phosphate ester fluid with (a) coal, (b) a representative polyvinyl chloride sample, and (c) a neoprene type composition.

Jan 1, 1972

By James Noll, Sam Janisko

Underground miners are exposed to some of the highest levels of diesel particulate matter (DPM) in the United States. Therefore, it is important to monitor the exposure of miners to DPM, but it can be difficult because of the complex composition of DPM and the number of interferences. Currently, elemental carbon (EC) is used as a surrogate because it makes up a significant fraction of the DPM and is not affected by interferences. Standard measurement methods for EC can be time consuming and only record end of shift results. In this research, a laser absorption technique that enables one to measure EC concentration in near real time was shown to be a beneficial tool. The real time data showed that the fresh air being drawn into a stone mine was not properly reaching the working area and needed to be redirected to decrease DPM concentrations. The real time data also provided a more accurate efficiency ofan environmental cab compared to just using the standard method by detecting the opening of the cab's window and door. The EC optical monitor was also worn by researchers in a mine to show how it can give not only the average concentration for the shift but also reveal when and where a miner is exposed to DPM. Keywords: Laser absorption, diesel, elemental carbon, mining, exposure

By D. Harrington

The record of fatalities from mine explosions during the past 2 fiscal years has been anything but encouraging; more men were killed by explosions (379) than were killed from the ante cause during to' preceding 6 years combined (368). The reason for the large increase in the number of explosion fatalities during the past 2 years as compared with the previous 6 years is not entirely clear. In some instances, there has been laxity in the enforcement of State mining laws; in others, both workers and operating officials is have failed to observe recognized precautionary measures to prevent explosions. In many of the explosions that lave occurred within the asst few years in mechanized mines it has been evident that speed of operation and a demand for maximum tonnage at minimum cost resulted in neglect of ordinary safety measures.

Jan 1, 1942

By P. W. Jeran

The Stereonet Analysis Program (SNAP) is a mathematics tool which, by means of a computer, reproduces mathematically the manual techniques of pre- paring stereograms. This computer program was developed to provide a fast, accurate, and economical means of analyzing fracture orientation data. It is mitten in FORTRAN IV for use on a UNIVAC 1108 operating under an Exec II system, but can be adapted to other systems. SNAP is currently being used to aid in the analysis of cleats and other geologically induced fractures associated with coalbeds that are being mined underground, Methane flows through the coalbed and into these mine workings predominantly through the fracture system. Therefore, knowledge of fracture orientation is an invaluable aid in the development of methane control technology.

Jan 1, 1970

By R. A. Beall, W. E. Anable

The purification of hafnium by electron- beam melting at moderate energy inputs and at low pressures was examined in detail . Most metallic impurities and hydrogen were removed in the first few minutes of operation ; oxygen , carbon , and nitrogen were removed at a slower rate . Samples treated by electron bombardment suffered a small loss of weight and a gradual lowering of hardness . The magnitude of each change varied with the energy input and the duration of the melt . Analysis of the data confirms the loss of oxygen as a hafnium monoxide . Approximate activity coefficients for other contaminants are given .

Jan 1, 1964

Crystalline silica is the scientific name for a group of minerals composed of silicon and oxygen. The term crystalline refers to the fact that the oxygen and silicon atoms are arranged in a three-dimensional repeating pattern. This group of minerals has shaped human history since the beginning of civilization. From the sand used for making glass to the piezoelectric quartz crystals used in advanced communication systems, crystalline silica has been a part of our technological development. Crystalline silica's pervasiveness in our technology is matched only by its abundance in nature. It's found in samples from every geologic era and from every location around the globe. Scientists have known for decades that prolonged and excessive exposure to crystalline silica dust in mining environments can cause silicosis, a noncancerous lung disease. During the 1980's, studies were conducted that suggested that crystalline silica also was a carcinogen. As a result of these findings, crystalline silica has been regulated under the Occupational Safety and Health Administration's (OSHA) Hazard Communication Standard (HCS). Under HCS, OSHA regulated businesses that use materials containing 0.1 or more crystalline silica must follow Federal guidelines concerning hazard communication and worker training. Although the HCS does not require that samples be analyzed for crystalline silica, mineral suppliers or OSHA-regulated businesses may choose to do so if they wish to show that they are exempt from the requirements of HCS. Because crystalline silica is an extremely common mineral and the HCS will affect many mineral commodities, it is important then, that there be as clear an understanding as possible of what is and what is not crystalline silica, and where it is found and used, and how it is qualitatively and quantitatively identified. This primer is an attempt to accomplish this in as nontechnical a manner as possible. This primer will examine crystalline silica. Part I will describe, in nonscientific terms, what crystalline silica is and how we come in contact with it. Part" will discuss the regulatory decisions that have created new interest in this ancient and widespread substance and will present a nontechnical overview of the techniques used to measure crystalline silica. Because this primer is meant to be a starting point for anyone interested in learning more about crystalline silica, a list of selected readings and other resources is included. The detailed glossary, which defines many terms that are beyond the scope of this publication, is designed to help the reader move from this presentation to a more technical one, the inevitable next step.

Jan 1, 1992

By C. Q. Cupps

n view of increased interest in secondary recovery of oil in the Cut Bank field, Montana, a review has been made of unpublished data obtained during a 1943-44 study of reservoir oil characteristics in this field. Considerable uncertainty was attached to interpretations of subsurface oil sample analyses from six Cut Bank zone wells, one Lander sand well, and one Moulton sand well, because of adverse sampling conditions and wide range in the data. Much of this uncertainty has been removed by this review which has shown two of the Cut Bank zone samples and the Moulton sand sample to be representative of the reservoir oils. Estimates of original reservoir oil characteristics derived from differential-liberation analyses of these samples show that the oil in the Cut Bank zone was initially saturated at the gas-oil contact pres-sure, 750 psia, and the oil in the Moulton sand was undersaturated with a saturation pressure of only 380 psia. The rest of the samples were indicated to be nonrepresentative of the reservoir oils because of a disproportional vaporization of heavier components of the solution gas. The vaporization of these components is believed to be a cumulative effect of contact of the oil with bypassing, light-gravity gas which had been liberated at higher pressures from solution in oil farther back in the formation, or which had come from the gas cap, rather than from the singular effect of gas evolution caused by excessively low bottom-hole pressures. Change of oil composition caused by the latter was found to conform closely to that occurring during a differential liberation of gas in the laboratory.

Jan 1, 1967

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

APPENDIX C - HOISTING SYSTEMS - AVAILABLE EQUIPMENT C 1 - Introduction A survey has been made of available hoisting equipment which has applications for use in metal and non-metal mine emergency escape hoist systems. The information was gathered from a number of sources, including representatives in the USBM and MESA, mine operators, personal visits and telephone interviews with manufacturers, field visits to inspect equipment, advertisements, catalogues and indices of manufacturers. Wherever possible, technical specifications and prices were checked out with the manufacturer, or supplier. The sections on individual sub-systems and components, such as automatic control systems, winches and controls, are not intended to be all encompassing surveys. Rather a reasonable number of representative units in each category are discussed. The sample is large enough to provide a general picture of the kind of equipment available, including the abilities and limitations and a reasonable price range. The survey has been divided into six categories 1. Complete Hoisting Systems A Above ground installations B Below ground installations 2. Hoist Assemblies ^(Man-rated) 3. Hoists (not Man-rated)

Jan 1, 1976

By W. W. Adams

[The sfxteeith e-mud ?7ntior_,il SnS~ty Cn~potitior,, cohduc ted by th Bureau of Mines, United Stntes'I3epnrtzel?t oL' the Interior, hstc fist been closed, and the resvlt s reveal tbt t!:e co~yafir,~ compzniqs had fewer accir'.ents in prnyort?lon to t2.o numbcr,of nkr-l:q?lr~1 1:9:='czd thm in my other ycryx in t3o r~cordc of the conlcst, Pheco zrzu-J. con:estn me thus aclr,i-cvir.c; Shc?r purpoao of ~romo tine w.fe ty in t5c nip-i~y induc tq*.]

Jan 1, 1941