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By H. W. Kilau

Thermodynamic calculations indicate that an electrochemical cell might serve as an analytical device for determining the composition of high-purity metals. An equation, readily derived, for the cell voltage, E, is as follows: [E I RT In F NFe unknown sample T of L NFe standard] The cell, however, must come to equilibrium, must be reversible, and must have no thermal effects or complicating side reactions whose magnitude is indeterminable. This Bureau of Mines investigation explores the feasibility of an electrochemical technique for the analysis of high-purity iron. Experiments were conducted using room-temperature aqueous cells and high-temperature molten salt cells. The room-temperature cells proved to be irreversible. The high-temperature cells utilizing FeCl2 and a eutectic mixture of KC1-LiCl were reversible, but did not attain a constant voltage necessary for analytical considerations.

Jan 1, 1963

By August J. Kwitowski

The U.S. Bureau of Mines developed and tested a teleoperating system to control a new highwall mining system. A remote operator was provided out-of-sight sensory information and control of coal extraction and haulage equipment. Surface and production testing proved that the teleoperating system supplied the operator with sufficient sensory information to operate the mining system. Details on the teleoperating system provided in this report include (1) sensor selection, (2) a description of the electronic control system, (3) equipment selection and modifications, (4) the positive test results, and (5) recommendations for system improvements.

Jan 1, 2010

By C. W. Owings

Recent recommendations of the Bureau of Mines regarding, rock dusting to prevent dust explosions in coal mines have been issued as Mine Safety Board Decision 32 and printed as Information Circular 7109.5/ The last paragraph on page 2 of I. C. 7109 states: After a mine or any part of a mine has been rock-dusted, samples of dust for analysis should be taken from the floor, ribs, roof, and timbers at such intervals of time as will give apple warning of need far redusting in order to maintain the required minimum percentage of incombustible in the mine dust. Details of the methods of sampling and analysis are given in Bureau of Mines Information Circular 7113.

Jan 1, 1940

By F. S. Crawford

The average visitor to a large electric-shovel operation may wonder how electric power can be treated as carelessly as apparently it is in open-pit mining, and how the mining company can string it carelessly along the ground in great, black, hoselike cables, whereas the power company, which has learned to respect his deadly agency, keeps power lines far out of reach. This is explained by the fact that this particular kind of application of power to moving machinery requires the use of trailing cable instead of the more permanent type of construction that permits a moving contact, such as a trolley. The cables are designed to insulate fully the enclosed power lines against damage and loss of current; and employees are taught to handle them carefully, although engineers are not satisfied that the trailing cable is foolproof and are seeking constantly to improve methods and equipment to insure greater safety. In some sections they rely mainly on the construction of the cable and perfection of equipment, while in others additional precautions are taken, such as handling the cable with rubber gloves, slings, tongs, or loops. In some sections no temporary repairs are made to cables, while in others such repairs are made and later are vulcanized in the shop. At some operations the cycle of shovel duties is arranged so that cables are very seldom exposed to flying rock fragments while at others this exposure appears to be unavoidable. Methods of fastening the cable to the shovel frame and transporting the loose cable vary. Inspection and care of the cable are important in insuring its safety and durability. A limited amount of information was obtained by field engineers of the United States Bureau of lines from operators in various parts of the United States, as methods of handling electric-shovel operations differ with the districts; practices followed and equipment used in these districts are described in this circular.

Jan 1, 1936

By Wm. O. Vanderburg

This paper describing the mining practices at the Block P mine of the St. Joseph Lead Co. at Hughesville, Mont., is ore of a series of similar papers being prepared by the Bureau of Mines on mining practices, methods, and costs in the various miner of the United States. ACKNOWLEDGMENTS In the preparation of this paper the writer acknowledges the assistance of R. H. Willcomb, general manager, William Thorson, mine superintendent, and B. P. Bellport, mining engineer, of the Hughesville division of the St. Joseph Lead Co.; and of E. D. Gardner; supervising engineer, U. S. Bureau of Mines, Southwest Experiment Station, Tucson, Ariz.

Jan 1, 1931

By V. Castranova, K. Van Dyke

"I. INTRODUCTIONA mechanism which is present in leukocytes and capable of releasing histamine from rabbit platelets was first described by Barbaro and Zvaitler in I966. A soluble mediator between rabbit leukocytes and platelets was also detected by Siraganian and Osier in 1971. This factor was isolated and characterized in 1971 by Benveniste et al. and named platelet activating factor i PAF). It was shown to be released from rabbit basophils through an antigen - IgE-dependent mechanism. The presence of PAF in human leukocytes' and its aggregation and releasing effects on human platelets were also demonstrated. Chemical analysis has shown that PAF is a glycerophospholipid with a choline polar head group. an ester-linked acyl chain at the second carbon and a nonester link at the first carbon.' The structure of the mediator was found to be 1-O-alky1-2-acetyl-sn-glyceryl-3-phosphoryl choline and it has been chemically synthesized.""' A variable portion exists in the alkyl group attached to the first carbon which can have a variety of molecular sizes such as C and C (where Cu is more abundant). Recent work by Pinckard et al."" has shown that there are at least five variations of the alkyl group.PAF has been shown to have a broad range of biological effects. Release of PAF from alveolar macrophages may be important in asthma, allergy, and shock states. In a rabbit model of antigen IgE anaphylaxsis. PAF can induce all of the effects of antigen challenge and. therefore is presumed to be a key mediator in production of anaphylaxsis. In addition to aggregating and degranulating platelets it is a potent chemoattractant."" and causes contraction of guinea pig ileum contraction of lung tissue and enhanced capillary permeability PAF has important effects in the kidney and is also known as the renal hypotensive factor proposed by Blank et al. who found the structure of PAF independently of Benveniste et al.' In producing these responses. PAF acts by a receptor-like mechanism. In platelets. PAF selectively desensitizes itself but not thrombin or collagen. In smooth muscle tissues a similar phenomenon occurs with anaphylatoxin or other stimuli.In vivo. PAF probably acts in concert with other agents in producing its various biological effects. It causes platelets to release histamine serotonin and RCS (rabbit-contractile substance formed from prostaglandins PPG2, PGH2 and TXA2) which contracts rabbit aorta. PAF can cause cells to release SRS-A and leukotriene B."

Jan 1, 1989

By Thomas L. Chapman

The San Manuel is a deposit of low-grade disseminated copper ore. It was brought to the attention of the government in October 1942 through an application to the Reconstruction Finance Corporation for a development loan, supported by a report by Henry W. Nichols. Nichols' sampling of two outcrops containing copper silicate and his geologic map indicated that a minable body of copper ore might be developed. The Federal Geological Survey was requested to examine the property. The Survey mapped the geology in March 1943 and cut a few check samples, which substantially confirmed Nichols' sampling of the outcrops and a few shallow workings. The geologists of the Survey recommended some test drilling by the Bureau of Mines. The property was examined by the author and Wm. D. Hughes, associate engineer of the Bureau of Mines on March 22 and 26, 1943, and a preliminary drilling campaign was recommended. Five shallow churn-drill holes totaling 1,480 feet were put down under the supervision of Chas. A. Kumke, one of the Bureau's engineers, from November 23, 1943, to January 13, 1944. This work indicated that the deposit extended deeper than the 350-foot depth attained in the deepest hole and might have very considerable areal extent. Additional funds were allotted, and the drilling contract was extended twice to a final maximum of 17,000 feet with 2,000 feet maximum depth of hole. Drilling was continued by the Bureau of Mines until February 2, 1945, when 15,844 feet of hole had been drilled. The Magna Copper Co. took options on this and adjoining property in September 1944 and commenced drilling with two machines. It also engaged the two contract drills used by the Bureau after it stopped drilling. It exercised its options in August 1945 and organized the San Manuel Copper Corp. to operate the property. That company is continuing to explore the ore body with six churn drills. Thomas Lyon took options early in 1945 on holdings adjoining the San Manuel property on the east and is operating two churn drills. Exploration up to the completion of the last holes started by the Bureau of Mines indicated a block of ore 3,100 feet long, 400 to 800 feet wide, and 500 to 900 feet thick, and averaging about 0.8 percent copper. Subsequent drilling showed that the ore body extends considerably beyond this block. The axis of the ore body strikes about N. 61° E. Copper minerals are disseminated in hydrothermally altered quartz monzonite and monzonite porphyry. Ore outcrops in two small areas over the northeast part of the block. Elsewhere the copper-bearing rocks are capped by Gila conglomerate, which thickens toward the west and south. Drilling showed that the ore is in a thick, tabular body with a steep dip to the south. The ore body lies near the surface in the northeastern part of the block. The south side of the block is much farther below the surface than the north side. There the upper part of the copper-bearing rocks is lightly mineralized, so that the hanging wall of minable ore lies deeper than the base of the conglomerate cap, which thickens southward.

Aug 1, 1947

By Thoms L. Chapman

The San Manuel is a deposit of low-grade disseminated copper ore. It was brought to the attention of the government in October 1942 through an application to the Reconstruction Finance Corporation for a development loan, supported by a report by Henry W. Nichols. Nichols’ sampling of two outcrops containing copper silicate and his geologic map indicated that a minable body of copper ore might be developed. The Federal Geological Survey was requested to examine the property. The Survey mapped the geology in March 1943 and cut a few check samples, which substantially confirmed Nichols’ sampling of the outcrops and a few shallow workings. The geologists of the Survey recommended some test drilling by the Bureau of Mines. The property was examined by the author and W. D. Hughes, associate engineer of the Bureau of Mines on March 22 and 26, 1943, and a preliminary drilling campaign was recommended. Five shallow churn-drill holes totaling 1,480 feet were put down under the supervision of Chas. A. Kumke, one of the Bureau’s engineers, from November 23, 1943 to January 15, 1944. This work indicated that the deposit extended deeper than the 350-foot depth attained in the deepest hole and might have very considerable areal extent. Additional funds were allotted, and the drilling contract was extended twice to a final maximum of 17,000 feet with 2,000 foot maximum depth of hole. Drilling was continued by the Bureau of Mines until February 2, 1945, when 15,844 feet of hole had been drilled. The Magma Copper Co. took options on this and adjoining property in September 1944 and commenced drilling with two machines. It also engaged the two contract drills used by the Bureau after it stopped drilling. It exercised its options in August 1945 and organized the San Manuel Copper Corp. to operate the property. That company is continuing to explore the ore body with six churn drills. Thomas Lyon took options early in 1945 on holdings adjoining the San Manuel property on the east and is operating two churn drills. Exploration up to the completion of the last holes started by the Bureau of Mines indicated a block of ore 5,100 feet long, 400 to 800 feet wide, and 500 to 900 feet thick, and averaging about 0.8 percent copper. Subsequent drilling showed that the ore body extends considerably beyond this block. The axis of the ore body strikes about N. 61º E. Copper minerals are disseminated in hydrothermally altered quartz monzonite and monzonite porphyry. Ore outcrops in two small areas over the northeast part of the block. Elsewhere the copper-bearing rocks are capped by Gila conglomerate, which thickens toward the west and south. Drilling showed that the ore is in a thick, tabular body with a steep dip to the south. The ore body lies near the surface in the northeastern part of the block. The south side of the block is much farther below the surface than the north side. There the upper part of the copper-bearing rocks is lightly mineralized, so that the hanging wall of minable ore lies deeper than the base of the conglomerate cap, which thickens southward.

Aug 1, 1947

By James A. Browning

Following an unsuccessful attempt earlier in the program to develop and market a drill channelling machine, we have designed and tested a new continuous channelling method which reduces operating sound levels to below 100 db. This new method relies on a small diameter oxygen-enriched burner to produce narrow channels. Sound intensities are reduced substantially compared to conventional channel widths. They are further reduced by a water spray directed immediately above the flame. Baffles placed along the top of the channel will reduce sound levels to below 90 db. Cutting rates are greater than those of existing channelling burners with costs per unit of channel area substantially reduced for those cases where oxygen costs are reasonable.

Jan 1, 1981

By L. C. IlsLey

Cooperation between the United States Bureau of Mines and the Safety in Mines Research Board of Great Britain, continuous since 1924, has made possible this and other papers on safety subjects. Grateful acknowledgment is made to representatives of the Safety in Mines Research Board of the Mines Department for their assistance in arranging visits to several mine-safety stations, and to F. H. Wynne, Deputy Chief Inspector of Mines, Great Britain, for arranging visits to mines in Great Britain, Belgium, France, and Germany. During the summer of 1927 the writer had the privilege of visiting the mine-safety testing stations in Great Britain, Belgium, Germany, and France, in the order named. All of these countries have large coal mines, many of which are rated as gassy. Therefore, when the installation of electrical equipment is contemplated, each of these countries is confronted with the same safety problem as in the United States - the development of electrical equipment that will not ignite gassy mine atmospheres, should such atmospheres through neglect or accident surround the equipment. The means used by those countries in safeguarding gassy mines should therefore be of general interest to safety engineers in American coal mines, and it is proposed to give a brief survey for each of the four countries mentioned. The first of these surveys will cover conditions in Great Britain.

Jan 1, 1929

By Duvall Wilbur I.

This is the second report to be presented on th application of stress analysis to underground Mining problems. In part I2/ of this investigation the stress distribution around single openings in unidirectional and hydrostatic stress fields was analyzed. Relationships between maximum stress concentration and size and shape of openings were determined by the photoelastic method. In most cases the results were verified by mathematical methods This report considers the stress distribution in pillars formed by two or more openings in a. unidirectional stress field. Relationships between stress concentrations and size and shape of pillars are developed. Applied to mining, results snow how estimates may be made of the stress distribution in pillars, what factors cause high local stresses, and how local stress concentrations may be reduced by proper design of mine openings. The photoelastic method was used, as in Part I, to study the stress distributions, and, whenever possible, the results were verified mathematically. A description of the photoelastic method and equipment is .given in Part I.

Jan 1, 1948

By L. W. Kelly

The purpose of this circular is to show that, under the conditions prevailing in the Stony Point mine, wooden bolts were just as satisfactory as steel bolts or conventional timbering, with a reduction of approximately 80 percent in cost of material. This one fact alone is enough to justify an experiment with wood. This circular will show that production records have remained constant with both wooden and steel roof bolts. INTRODUCTION The successful use of steel roof bolts is now an accomplished fact in the coal industry, but the use of wooden bolts in place of steel is a rarity. The first experiment with wooden roof bolts was mane in 1949 in the Rio Verde mine, Norton Coal Corp., Nortonville, Ky.2/ This experiment was successful; the company obtained excellent results, but operations in the mine were suspended before enough time had elapsed to prove the value of wooden roof bolts conclusively. It is obvious that, if wooden roof bolts could be used in place of steel bolts or conventional timbering-methods, every mine operator would use word, as the cost is only a fraction of the other two methods. The Stony Point experience has proved conclusively that, under certain conditions and with a certain type of roof, wooden roof bolts can be used successfully.

Jan 1, 1952

Tax for Toxic Waste Cleanup. - The Superfund Act of 1980 became effective April 1, and provides that producers of certain metals and chemical substances are to be taxed in order to fund toxic waste cleanup. Industry will provide 88% of the 5-year, $1.6 billion fund. The Environmental Protection Agency will administer the Act, but the Internal Revenue Service will be responsible for collection of the industry tax. Under the Act, nickel companies, for example, will be required to pay a tax of 0.225 cents per pound on pure nickel products produced or imported into the United States. Standard for Exposure to Lead. - The Occupational Safety and Health Administration (OSPA) has announced a stricter standard on the test of a worker's exposure to lead. Effective May 15, in all lead intensive occupations with the exception of those at primary and secondary lead smelters, a worker would have to be removed from his work station if the level of lead in his blood tests out at 60 micrograms of lead per 100 grams of blood, instead of the previous standard of 70 micrograms. In the case of primary and secondary lead smelters, the ruling has been stayed until June 1, 1981, to allow time for further study.

Jan 1, 1981

By L. E. Dalverny

This Bureau of Mines report describes the deployment, 5-month operation, and lessons gained from a continuous gas monitoring system using sampling-tube bundles at an underground mine fire in West Virginia. Research information gained indicates the utility of relating certain gas concentration ratios to events during fire development, mine reventilation, and mine recovery. In addition to monitoring the quality of remote fly ash seals, the system provided timely warning of dangerous gas concentrations which developed during surface and underground recovery activities. An evaluation of system components is supplemented by recommendations for improvements.

Jan 1, 1975

By J. R. Long

The investigations described herein are concerned with a portion of a systematic research, by the Federal Bureau of Mines on ductile titanium. The Bureau's work on the metal has resulted in development of a semi commercial process for the preparation of titanium and has also made available significant information on the fabrication and physical properties of this new strong, light, corrosion-resistant metal. Considerable interest has been aroused by this work, and a number of other laboratories have begun similar investigations. However, the necessity for Consolidating titanium by normal powder metallurgy methods presents difficulties in producing commercial forms and shapes on a large scale. This investigation was therefore undertaken for the purpose of improving the technique for consolidation of titanium powder into solid nonporous metal.

Jan 1, 1949

By J. W. Eckerd

The crushing of chestnut-size (1-5/8 by 13/16 inch) Pennsylvania anthracite in four commercial crushers (impact) jaw) hammer-mill) and gyratory types) was studied by the Bureau of Mines to determine which could produce the largest proportions of buckwheat Nos. 1 and 2 sizes (9/16 by 3/16 inch). Single pass dry and wet crushing techniques and the effect of stage crushing were evaluated. Calculations were made to show the effect of closed-circuit reduction on production rates and yield of the various sizes. The data show that the gyratory crushers produced the greatest percentage of the desired sizes. A ring-type hammer mill produced the greatest tonnage of buckwheat No.1 and rice (14.9 tons per hr.) during dry grinding tests) but the yield of these sizes was only about 55 percent) as compared with 62 to 70 percent for the gyratory crushers. The impact and jaw crushers produced the smallest amount of buckwheat and rice and the largest quantity of oversize material.

Jan 1, 1960

By Jeanne A. Zimmer, Brad Smith, Steve Viles, Andrew B. Cecala

A recent report evaluating silica exposure levels in the metal/nonmetal mining industry noted that bag packaging and loading are some of the occupations at the greatest risk. In addition to dust problems, the bag-stacking process is labor intensive, making lost-time injuries common due to back fatigue and strains. During the bag-stacking process, a significant amount of dust can be generated, mainly from product on the outside of the bags and from dust escaping the bag valve upon impact of the bag on the pallet. In an effort to address dust-exposure and back-fatigue issues, Malvern Minerals Co., Hot Springs, Ark., made two major improvements to its ground silica stacking facility. First, the company purchased a semi-automated bag palletizing system (Figure 1). With this system, the bag stacker does not lift the bags, but slides them across a metal table. Small jets of air exit through perforations in the table top (similar to an air hockey game), allowing workers to more easily slide each bag into the proper position. After each layer of bags is completed, the table slides open, and the entire layer of bags is loaded onto an underlying pallet. The table then closes, readying it for another layer of bags. After the entire pallet is loaded, the unit delivers the pallet to a shrink wrap and forklift pick-up area. In addition to this semi-automated palletizing unit, Malvern Minerals purchased an Overhead Air Supply Island System (OASIS) to lower the bag stacker's dust exposure. The OASIS takes outside air, directs it through MEASURING RESPIRABLE DUST The bag stacker's respirable dust exposure was monitored using a RAM-1 instantaneous dust monitor to evaluate the impact of the various changes on the palletizing process and dust-control equipment. The bag stacker wore a vest that held the 10-mm Dorr-Oliver cyclone, which classifies the respirable portion of dust. Flexible tygon tubing was used to connect the cyclone to the RAM-1 dust unit, allowing the bag stacker to perform the palletizing process with minimal interference. The RAM-1 measures respirable dust concentrations by light scattering with a sensing chamber. This device closely simulates gravimetric measurements when calibrated for a specific dust. This instrument is ideal for comparative evaluations, as was the case in this study. Since the RAM-1 is not an MSHA-approved instru¬ment for dust compliance sampling, the dust concen¬trations listed in this article should be used as a com¬parative value of respirable dust concentration and not to determine actual dust concentrations from a com¬pliance standpoint.

Introduction The NIOSH Office of Mining and Construction Safety and Health Research has redesigned its Mining Safety and Health Web topic page. The updated page incorporates a significant amount of new safety and health information, plus an improved layout to better serve stakeholder needs. It also provides back-ground information about the NIOSH Mining Research Program, including research awards, core competencies, unique labs, community and educational outreach, and a brief discussion of how the research program is structured. The new Web topic page can be found at www.cdc.gov/niosh/mining. "Search" Feature The redesigned Web topic page features improved search capabilities. The "Search Mining" feature on each page lets you search only the NIOSH Mining Safety and Health Web topic page. The user can still search the entire NIOSH Web page by using the "Search NIOSH" option. New Safety and Health Topics Developers expanded the "Safety and Health Topics" and reorganized the site to make it easier to find information. Each topic link now has a significant amount of new and updated information, as well as links to related topics of interest. Safety and health topics include dusts, diesel exhaust, hearing loss, contact with electric current, fires, explosives, ventilation, emergency management, new and older workers, and education and training. All topics can be accessed from the home page (Figure 1). Publications Although the Web topic page highlights many of the most requested publications on the safety and health topic links, you can find a complete list of downloadable publications as well. More than 600 mine safety and health publications are now downloadable from the page. Short summaries let the user quickly identify publications of interest. Products The updated Web topic page offers more than 120 NIOSH mine safety and health products, including training exercises, toolbox talks, videos, computer software, guides, and checklists, many of which are downloadable. If not, instructions are given on how to obtain copies. Some of our products include: • Software to analyze horizontal stress, design pillars for longwall mines, and select roof bolts for ground control. • Educational software including the Hearing Loss Simulator, which simulates the effects of noise and aging; and Coal Country, which teaches children about coal formation, mining techniques, and everyday uses of coal. • Utility software including the HazCom Helper software to assist individuals in writing a HazCOM plan, as required by the Mine Safety and Health Administration (MSHA), to track hazardous chemicals at their mine sites. • Guides for troubleshooting roof support systems, under-ground workstation design, and seating design. • Training exercises and videos that can be used for safety training. Data and Statistics General mining statistics are used by a wide variety of stakeholders. The NIOSH Mining Web topic page offers statistical graphs, tables, maps, fact sheets, and other publications that document the mining population, injuries, fatalities, diseases, and occupational exposures for all mining commodities. If users prefer to analyze data themselves, downloadable files of MSHA data are available. These cover employment, production, injuries, fatalities, and accident data from 1983 to the present and are available in both SPSS® and dBASE® formats.

Jan 11, 2005

By R. L. Hopkins

The work described was performed to determine whether sulfur compounds of the thienothiophene class occur in crude oil. The presence or absence of various classes of sulfur compounds in crude oils is of interest and value to petroleum science. The Bureau of Mines, for the first time, identified hydro-carbon products of desulfurization that point directly to the identity of two individual thienothiophenes, namely 3-methylthieno[2,3-b]thiophene and 2-meth-ylthieno[3,2-b]thiophene, in Wasson, Texas, crude oil. These identifications, described in detail, were accomplished using microdesulfurization, mass spectrometry, and gas-liquid chromatography.

Jan 1, 1966

By Richard E. Ray, George N. Aul, Fred Garcia, William P. Diamond

Increasing longwall panel dimensions, particularly face width in gassy coalbeds, may result in unexpected increases in methane emissions. To investigate this problem, continuous longwall face emission monitoring studies were conducted at two adjacent mines operating in the Pocahontas No. 3 Coalbed, where longwall faces were to be extended from 229 to 305 m (750 to 1,000 ft). It was predicted by regression analysis of methane emissions data from 229 m (750 ft) wide longwall faces that extending faces to 305 m (1,000 ft) would increase methane emission rates by only 7 percent (0.6 m3/min (20 cfm)), to 8.6 m3/min (304 cfm) at the VP-1 Mine. In contrast, it was predicted that extending faces at the VP-3 Mine could increase methane emissions by as much as 13 percent (1.8 m3/min (65 cfm)) to 16.1 m3/min (567 cfm). The geologic and mine design factors influencing the variation in face emissions between the two mines will be discussed.