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By G. S. Scott, G. W. Jones

Trichloroethylene (CHC1CC12) is an important solvent for fats , resins , bitumens, rubber , sulfur , and phosphorus . It is used extensively in drycleaning because of its low order of combustibility and has recently been proposed as an inhalation anaesthetic . Its physical properties have been described by Carlisle and Levine . It is usually considered a noninflammable material ; however , substances that are noninflammable when mixed with air are not necessarily noninflammable when mixed with oxygen . Thus , Hewer's statement that " Trichloroethylene*** is not inflammable under any circumstances , nor will its vapor explode when mixed in any proportion with air , oxygen, or nitrous oxide , " requires qualification , especially in anesthesia, where pure oxygen may at times be substituted for air , This report gives the results of tests made to determine the inflammability of trichloroethylene in various mixtures of oxygen and nitrogen . The trichloroethylene used was Eastman's No. 1300. The boiling point was given as 86 ° to 87 °C . The specific gravity and refractive index of the sample measured in this laboratory were , respectively, 1.45 and 1.4759 at 25 °C .

Nov 1, 1942

By Donald E. Graham

A mineral survey of a 12,350-acre portion of the 13,150-acre Juniper Creek Wilderness Study Area (WSA) in southwestern Idaho was conducted by the U.S. Bureau of Mines in 1984. The area is entirely underlain by thick flows of Banbury Basalt. Rhyolitic tuff of Little Jacks Creek is exposed in the walls of the Owyhee River canyon beneath the basalt. Minor units of lacustrine sediment occur between the volcanic layers. No mines or claims occur in the area, and no mineralized zones were found. The study area is covered by oil and gas leases or lease applications; there has been no known exploration.

Jan 1, 1985

By George S. Rice, J. W. Paul, E. H. Denny

Data assembled by the Bureau of Mines , coupled with requests from coal companies , have emphasized the desirability of establishing standardized specifications for brattice cloth with particular respect to durability and fireproofing . Brattice cloth is a canvas or other material , often covered with some fireproofing composition , which is used extensively in coal mining for temporarily deflecting air into pillar workings and maintaining ventilation at the working faces . These specifications will be established , it is planned , through a cooperative program in which the U. S. Bureau of Standards will make a series of tests of various brattice cloths treated with respect to fire- resisting qualities and the U. S. Bureau of Mines will continue to assemble field data on the use of brattice cloth . Plans now are being made for this cooperative work. Without attempting to make a complete survey , the Bureau of Mines has made preliminary studies and investigations , and verious representative coal - mining companies have furnished detailed information . The information thus gained will be used as the basis for the cooperative investigation , but the Bureau of Mines would welcome additional information from mine operators on the character and weight of brattice cloth , conditions of use , durability , quantity employed and price . Such information should be sent to the Director , Bureau of Mines , Washington , D. C. The mine operator is interested in procuring at reasonable cost a brattice cloth with lasting fireproofing quality and of as great durability and strength as possible . There has been a lack of assembled data and knowledge regarding the subject , but the Bureau of Mines feels that this lack of knowledge may be overcome if the coal -mining companies will lend their hearty support to the cooperative investigation and submit information relative to the use of brattice cloth in their own properties . Information contained in this report is based on data obtained from coal operators in bituminous districts of Pennsylvania , Alabama , Utah , Indiana , Illinois , Colorado and Nova Scotia .

Feb 1, 1923

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 H. C. Brunaugh, James Westfield, R. W. Whittaker

"INTRODUCTION The purpose of this circular is to describe the sealing off of a mine fire and subsequent use of carbon dioxide gas to extinguish it.A fire of electrical origin occurred in the Valier mine of the Valier Coal Co., Valier, Franklin County, I11., on March 29, 1949, at about 1:35 p.m. It was discovered about 3:35 p.m. in 5 south west intake airway inby 1 and 2 west panels. The No. 5 southwest airway had caved, and the fire was in the top coal beneath a large fall of rock. All men, except officials, were ordered from the mine. The mine officials decided to seal the fire, and four temporary seals were erected, which isolated approximately 200 feet of 5 south west entry. The seals were completed on March 30 at 2:45 a.m., but on March 31, at 3;40 a.m,, two of them were blown out by an explosion of gas that was produced by the fire. The two seals were rebuilt, the work being completed on March 31 at 12:00 noon, but they were blown out by another gas explosion at 12:10 a.m. on April 1. It was then decided to extinguish the fire with water if possible.To accomplish this, concrete-block dams were constructed. On April 1, about 4:25 a.m., when the dams were about half completed, water was introduced into the fire area through a 2-inch pipe.On April 4, J. G, Crawford, general manager of the Valier Coal Co., notified James Westfield, chief of the Vincennes (Ind.) Branch, U. S. Bureau of Mines, by telephone of the fire in Valier mine and requested assistance to combat it. Westfield, accompanied by F. J. Smith and H. C. Brumbaugh, Federal coal-mine inspectors, went underground and inspected the seals and dams. Later, during a conference with company officials, it was decided that the concrete-block dams were not strong enough to withstand the hydrostatic pressure that would be produced by flooding the fire area. It was then decided to use carbon dioxide gas to extinguish the fire. Four seals were completed, and 5 tons of carbon dioxide gas was introduced into the fire area, which extinguished the fire."

Apr 1, 1950

By W. E. Anable

The Bureau of Mines studied the purification of commercially available yttrium by melting it in a 100-kw electron-beam furnace. Button-scale melts were made to determine the ultimate purification that could be attained by melting yttrium at 1,733° to 1,770° C at low pressure (0.05 to 0.1 micron) for 1 to 120 minutes. In addition, numerous melts were made to study the effect of doping yttrium with carbon, 17 selected metallic additions, and 3 compounds. Except for nickel and zirconium, the metallic impurities in yttrium were lowered significantly on extended treatment; silicon was lowered only slightly. The nonmetallic impurities} oxygen, nitrogen, and carbon, were not lowered except on short exposures. In isolated instances, the oxygen content was lowered from 5,860 ppm to about 5,000 ppm. In most instances the carbon con-tent was lowered from 545 to about 220 ppm in 20 minutes and then increased again. It was concluded that yttrium cannot be purified by direct heating or by the doping technique employed.

Jan 1, 1965

By R. L. Grayson, T. Simonyi, R. A. Andrel

"The purpose or this paper is to disclose analytical, statistical, and observational results relating to mineralogy and trace elements in respirable dust samples collected from two different mines in West Virginia. Samples were taken from longwall panels, and the panels operated in different coal seams, one located in the northern part or the state and the other in the southern region. Mining conditions and equipment arrangements on the panels will be described along with dust control techniques used. Results from sample analyses are summarized with emphasis on relationships between mineralogy, trace elements and mineral particle size to worker locations. Correlations are made between micro x-ray diffraction and energy dispersive x-ray analyses for sample mineralogy.IntroductionThrough the work of many researchers worldwide, the health of coal miners in modern societies is now protected from harmful exposure to respirable coal mine dust. A vast amount of research culminated in the exposure-response model of Jacobsen, et al, (l) which has been used to establish the 2 mg/m3 exposure limit in the United States. According to the model exposure to respirable dust for 35 years at this level or less could prevent the occurrence of a clinically significant case of coal workers' pneumoconiosis (CWP) in a miner. The exposure limit, of course, must be adjusted whenever greather than five percent free silica exists in the respirable dust.The Jacobsen model was built around a mean mass concentration exposure, which generally showed the highest correlation with both incidence and progression of CWP. As Morgan, et al noted, however, the quantity of respirable dust inhaled is not the only significant factor. 2) They noted that although mass of respirable dust correlates highe.st with the incidence of CWP, it is not a causal factor. Admittedly, the insidious processes causing the disease occur at the lund cell-dust particle level."

Mar 1, 1989

By Lorenz E. Sieffert, Lawrence B. Berger, H. H. Sehrenk, Ralph W. Stewar, James A. Gale

"INTRODUCTION The purpose of the investigation discussed in this article was to evaluate the toxic hazard from gases produced when thermosetting plastic materials used for electrical insulating purposes are burned or thermally decomposed in enclosed spaces. For brevity the term ""toxicity"" is used throughout the article to refer to the nature of gases produced under these conditions. A need for immediate study of the problem was created as a re¬sult of the battle damage reports received from various United States Fleet units. These indicated that the fumes emitted when these materials were burned or thermally decomposed had, in several instances, resulted in toxic atmospheres. In attempting to develop a suitable test method for evaluating toxicity, it was recognized that no single test procedure could be expected to duplicate the variety of conditions that might exist in an actual fire aboard ship. In view of the immediate need, however, it was felt that considerable information could be obtained, at least to classify comparatively the several types of materials as to the toxic effect caused by burning or thermal decomposition, through the development of a sound empirical method which could be applied to all of the materials. On this basis, it was decided to modify the Navy flame resistance test for thermosetting plastics to render it applicable to the determination of the toxic, gases evolved when this test was employed. A wide variety of materials was tested, both molded and laminated, to cover the types commonly used by the Navy in electrical applications. Toxicity determinations were conducted at the Bureau of Mines Central Experiment Station, Pittsburgh, Pa. Parallel tests, to determine the flame resistance of the materials, were conducted at the Material Laboratory, U. S. Navy Yard, New York, N. Y."

Oct 1, 1947

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 W. P. Yant

[At the majority of mines where flame safety lamps are used either as working lights or as a means of detecting gas, no check it made on this condition of the various parts of the lamp and their assembly other than a visual ink inspection. Although this inspection should be made carefully in view of tae serious consequence that may follow Vie use of a faulty lama, In many instances the inspection is of a perfunctory nature. The Bureau of Mines has therefore designed a small box or gallery for testing lamps for defects and improper assembly before they are taken into the mine. The test simulates the condition when a lamp is extinguished by its introduction into an explosive mixture and the operator attempts to relight the wick while the lamp contains the explosive mixture. This test is more rigorous than merely subjecting a lighted lamp to an explosive methane-air mixture. In the latter test the products of combustion tend to blanket the propagation of flame from within the lamp to the exterior, especially if there are defects at the top of the gauzes. Moreover, when the lighted lamp is subjected to an explosive methane-air mixture the methane builds up slowly within the lamp until the lower inflammable limit is attained, whereupon a feeble explosion occurs within. If the nonlighted lamps is first filled with the methane-air mixture that gives the maximum violence and is than ignited, the dampening effect of products of combustion is obviated and the strain on defects is]

Jan 1, 1930

By F. W. Hoertel

Tungsten from the hydrogen reduction of WF was vapor - deposited to coat MERM (Material Evaluation Rocket Motor ) graphite and rhenium- lined graphite nozzles . These nozzles have surface configurations that preclude the conventional fabrication of high- density- tungsten liners . Operation at 550 ° C produced selectively placed uniform coatings of specified thicknesses at near theoretical density . An acceptable coating could not be deposited on a beryllia nozzle because of an undesirable side reaction between the substrate and one or more of the products of the reduction reaction .

Jan 1, 1964

By Walter W. Hyde

This paper describing the mining and preparation of sand and gravel for a number of special markets by the East Texas Gravel Co., Dallas, Tex., is one of a series being prepared on the subject by the United States Bureau of Mines. These articles are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total production costs. It is recognized that publication of total production costs might in many instances cause embarrassment to individual producers as well as to the industry as a whole, but on the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue.

Jan 1, 1931

By A. W. Deurbrouck

Four samples of Pittsburgh-bed coal, of various size consist and ash content were dewatered in a pilot-size vacuum-disk filter partially enclosed with a steam jacket. Steam fed at 2.5 to 12.5 pounds per minute reduced the moisture content of the filter cakes from 2.8 to 13.8 percentage points more than normal vacuum dewatering. Approximately 1.5 pounds of steam was required to remove 1 pound of water.

Jan 1, 1966

By R. C. Hickman

"INTRODUCTION .As part of its spot drilling program, the Bureau of Mines core-drilled seven holes on the Alexander and Barber properties in Spartanburg County, S. C.Extensive surface float and outcrops of sillimanite schist on these properties appeared to justify drilling, which did not prove satisfactory, however, owing to the spotty occurrence of the schist bodies and the poor core recovery in the decomposed schist.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, Oliver C. Ralston, chief, analyzes samples and performs beneficiation tests.This project was under the immediate supervision of Mitchell H. Kline, chief, Raleigh Division, Mining Branch, Bureau of Mines.LOCATIONThe Alexander and. Barber properties are in the southern part of Spartanburg County, S. C. The Alexander property is about 5 miles cast of Woodruff. It is reached from Woodruff by driving east 5 miles on a macadam road to the intersection with an unsurfaced road near Unity Church. The farm house on the property is 0.4 mile north on this road. The sillimanite outcrop is in a field approximately 1,200 feet east of the farm house. The Barber property is about 2 miles north along the unsurfaced road that passes the Alexander property."

Sep 1, 1947

By Homer J. Ballinger

The Mary Arnold Mining Co. in 194.3 owned 292 acre s of mineral land in Christian County, Mo., and was one of two companies with milling facilities in southern-central Missouri. Production from this property between 19.37 and 1941 amounted to 1,718 tons of zinc in the form of zinc concentrate. Because of the urgent war requirements for additional zinc and the existing facilities for treatment of zinc-lead ores at these mines, in the winter of 1943-44, the Bureau of Mines investigated the deposits by churn drilling in an endeavor to outline enough ore to maintain production of zinc from this district. Five holes aggregating 1,043 feet were bored.

Jan 1, 1948

By Wesley A. Grosh

The Toncrae-Howard copper deposits in Floyd County, Va., were first mined about 1800. The property has been operated or under development at various times since then for iron, copper or sulfur, although the total production has been small. The deposit consists of a vein or zone of sulfide mineralization in schist composed mainly of pyrrhotite with minor copper values in the primary zone and some rich areas of copper mineralization in the altered zone. The Bureau of Mines, in an attempt to develop minable copper ore during the war, opened part of the mine for examination and sampling, deepened the shaft and other underground work, and drilled 29 holes totaling 2,187 feet.

Jan 1, 1948

By E. G. King

Many of the rare-earth oxides are now commercially available in pure form and they have a variety of potential technical uses. Thermodynamic data for these oxides, however, are rather sparse. It is one of the functions of the Bureau of Mines to fill the need for this type of information. This report gives the results of low-temperature heat-capacity and high-temperature heat-content measurements by the Bureau of Mines of lanthanum sesquioxide. The entropy at 298.15° K. was evaluated and heat-content and entropy increments above 298.15° K. were obtained to 1,800° K. The results were combined with the known heat of formation at 298.15° K. to derive heats and free energies of formation at higher temperatures. Sufficient information is now available to permit reliable thermodynamic calculations involving lanthanum sesquioxide within the temperature range 298° to 2,000° K.

Jan 1, 1961

By Graham W. Mark

A chemical method of analysis for beryllium was developed recently in Bureau of Mines laboratories. In this method, quinalizarin (1-2-5-8 tetrahydroxyanthraquinone) in N/4 NaOH is used as a colorimetric titration reagent. This solution has a reddish-purple color, whereas the solution containing equivalent amounts of beryllium and the dye is rather blue. In the titration procedure, standard quinalizarin solution is added to the unknown beryllium sample and to two standard beryllium samples of different but known concentrations. Then adjustments in concentrations of BeO in the two known and of quinalizarin in all three are made until the red-violet shade of the unknown is halfway between that of the two knowns. The amount of BeO in the unknown is calculated from the known BeO content of the solutions between which it lies. It is extremely difficult to distinguish the slight differences in shade of these solutions without the use of a proper light filter, especially when the concentration is over 0.1 mg. of BeO, so a study was made of the transmission characteristics of quinalizarin in N/4 NaOH and of the corresponding beryllium complex to determine what filter would give the most contrast.

Jan 1, 1950

By Steven W. Schmauch

The Ruby Mountains study area encompasses 75,615 acres managed by the U.S. Bureau of Land Management in Madison County, MT. A mineral survey was conducted by the U.S. Bureau of Mines and U.S. Geological Survey in 1984. Bureau of Mines personnel reviewed literature and county mining records, and examined prospects or mineralized areas to determine mineral resources. Geological Survey personnel evaluated the area by geochemical sampling and geophysical surveys. There are no organized mining districts and no current claims in the study area. Significantly mineralized quartz veins, shear zones, or talc bodies apparently do not exist within the study area. A small part of the Kelly Iron Deposit is inside, but dips away from the study area; the main occurrence is estimated to have 32 million tons of subeconomic resources that average 21 percent iron.

Jan 1, 1985

By E. C. Tarpley, H. M. Cooper, R. F. Abernethy

The standard method of employing preliminary air-drying to determine the moisture in coal has been criticized with respect to the loss of heating value from excessive air-drying. By this method, the coal is air-dried at approximately 10-15° above room temperature with the loss in weight being less than 0.1 percent per hour, and then the residual moisture at 105°C is determined. The total moisture is calculated from these two values.

Feb 1, 1948