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By K. E. Stanfield

[Asphalt ~~d road oil ar8 the principal products manufactured from Wyor.1in~ Ilblack oilo" \r,hich, beca.use of th?lir hig.~ E\.sphal t and hig} sulfur COi.1Jce~1t, .!?re difficult e':ld costly to refine into hi?;h-gra.de motor f 101s, burning oils. and lucri ants by presont mothods. Accordin~ly. the demand for truHle asphaltic renidl urn for the construction of roade aJ1.d other uses is 3. controlling factor in the quantity of crud~ oil prod ICed. The increasiilg -u.tilization of special aST>ha.lts as ine}""Pensive bonding, in-]

Jan 1, 1941

By L. C. IlsLey

In the normal operation of mines, the aggregate effect of many seemingly minor op rations may be very important as respects economy and safety. Anion: these operations is the method employed in coupling and uncoupling mine cars. For economic reasons the equipment in mines has not been protected as well as railroad equipment. It is pertinent that haulage accidents rank second in severity among mine accidents, and that manual coupling of cars has been one of the most frequent causes of such accidents. One study4/ revealed that coupling was responsible for about 20 percent of haulage accidents underground. A review of early conditions on steam railroads, which were responsible for the introduction of safer methods of coupling cars, indicates how conditions in might be improved. THE STORY OF RAILROAD COUPLING As any considerable improvement in mine-car coupling probably will follow lines somewhat similar to those that brought order out of chaos for the railroads, it seems appropriate to review briefly the steps taken to improve railroad coupling from the days of link and pin couplings of various types to the adoption of the standard ?M.C.E? automatic coupler.

Jan 1, 1943

By James E. Bell, Clyde B. White

"INTRODUCTION The Friedensville district was one of the most important zinc-producing areas in the United States from 1859 to 1893. The ore minerals near the surface were principally calamine and smithsonite, but with depth sphalerite was found in increasing proportions. The ore bodies of the district are reported to have been in chimneys, occurring in folded and faulted beds of Beekmantown limestone of Ordovician age.The Correll was one of five mines near Friedensyille that were exten¬sively exploited. The high-grade ore shoots were mined to a depth of several hundred feet, but it is believed that inability to compete with lower-cost production elsewhere, rather than exhaustion of the ore bodies, compelled the mines to close.There is no record to indicate that any attempt was made during the period of operation to explore for additional ore in the limestone beds down the dip below the mine workings. The possibility that exploration might reveal additional ore in the limestone beds below the known ore shoots led the Bureau of Mines to diamond-drill the Correll property between September 1943 and January 1944."

Jan 1, 1948

By Walter Kawa

The hydrogenation of phenyl ether, benzyl ether, and phenyl sulfide in the presence of iron catalysts was studied by the Bureau of Mines to gain a better understanding of the role of iron catalysts in the hydrogenation of coal. The carbon-oxygen and carbon-sulfur bonds in these compounds may be similar to some of the carbon-oxygen and carbon-sulfur bonds in coal which react during the early stages of liquefaction by hydrogenation. Experiments were made in batch autoclaves for 4 hours; hydrogen was at a pressure of about 540 atmospheres. In the hydrogenation of phenyl ether at 400° C, metallic iron catalyzed both hydrogenolysis (splitting-hydrogenation) and nuclear hydrogenation (addition of hydrogen to aromatic rings) reactions, Products were principally benzene and cyclohexane. The activity of metallic iron was decreased by adding carbon monoxide or a reactive sulfur-containing organic compound. Ferrous sulfide catalyzed the conversion of phenyl ether to benzene, phenol, and small amounts of cyclohexane. Hydrogenolysis of benzyl ether was catalyzed by metallic iron and to a lesser extent, by ferrous sulfide at 250° C. No nuclear hydrogenation was observed with either catalyst. Conversion of phenyl sulfide to benzene was nearly quantitative in experiments made at 250° C with equimolar quantities of phenyl sulfide and metallic iron or iron as ferric oxide. Conversions of metallic iron and ferric oxide to ferrous sulfide were nearly stoichiometric. No reaction of phenyl sulfide occurred in the presence of ferric oxide and water, and very little occurred in the presence of metallic iron and water. Ferrous sulfide also catalyzed the hydrogenolysis of phenyl sulfide to benzene, but conversion was lower than in experiments with metallic iron or ferric oxide. The activity of ferrous sulfide was increased by adding water and decreased by adding hydrogen sulfide. The results of this study suggest that ferrous sulfide is an active form of iron when iron is used as a catalyst for the hydrogenation of coal.

Jan 1, 1963

By E. S. Leaver

The mineral value in the ores from the Mother Lode mining districts of California is almost entirely gold, Although many mines have produced extremely high-grade ore the usual mill grade averages approximately $7.00 gold per ton. Fully 80 per cent of the gold has been and is now being recovered by amalgamation. Various methods have been introduced to recover the gold that was not obtained by the amalgamation processes. They include vari¬ous kinds of gravity concentration which in some cases were followed by chlorination or cyanidation. The usual practice includes only stamp battery, plate-amalgamation, and vanner concentration. In the very early practice the tails were run to waste through the main drainage streams of the different mining districts. During later years very large storage dumps have been impounded. These old tails, together with those being saved from present mills, furnish the problem discussed in this article. The clean sand portion of these mill tails is amenable to the usual cyanidation. The slime portion contains the major amount of the gold lost, but it also contains 1-1/2 to 3 per cent carbon, which precludes direct cyanidation of this part of these low-grade waste tails. The black carbonaceous slime portion is the particular problem considered in this report.

Jan 1, 1930

By Clarence Hall, J. J. Rutledge

Many of the fatal accidents in coal mines have resulted from the Explosives used in Use of explosives for breaking down the coal. These accidents have resulted both from the use of explo- sives that were not suitable and from the careless or improper use of suitable explosives. Investigation has shown that one of the commonest causes of dis- astrous explosions in the coal mines in this country has been a blown- out shot of black blasting powder or dynamite. The dangers that attend the use of these explosives were perceived several years ago, and in consequence the attention of powder manufacturers was directed to the production of explosives that would be less liable to ignite inflammable gas or dust. The manufacturers have been so successful in their efforts that it is now possible to obtain explosives which yield much shorter and quicker flames than black blasting powder or dynamite, and hence are much less dangerous to use in fiery or dusty coal mines. of explosives. To find out which of the many grades of short-flame explosives Government tests have the qualities that render an explosive most effective and least dangerous for mining coal, the United States Government established a testing station at Pitts- burgh, Pa., in 1908. This station is now under the charge of the Federal Bureau of Mines. Before the station was opened a state- ment of the requirements that the explosives in question would have to satisfy was drawn up and sent to manufacturers. A number of these sent explosives to be tested, and on May 15, 1909, a list of the explosives that had passed the tests was published. Since that date other brands of explosives have been tested and three more lists have been issued. The latest list, published in Miners' Cir- cular 2, Bureau of Mines, contained the names of no less than 71 explosives that had passed the tests prior to January 1, 1911.

Jan 1, 1912

By X. Shi, V. Vallyathan, N. S. Dalai

"Electron spin resonance (ESR) measurements show that grinding of quartz particles in air produces silicon-based (Si- and SiO-) radicals which decay with aging in air. ESR spin trapping measurements provide evidence for the generation of hydroxyl and possibly superoxide radicals from a suspension of fresh quartz particles. The hydroxyl radical generation potential of the fresh quartz particles decreases on storing in ambient air and on the addition of catalase, superoxide dismutase, desferoxamine, or DMSO. Silica-induced lipid peroxidation also decreases on storing the fresh particles in ambient air. These findings suggest that oxygenated radicals play a role in the biochemical mechanism of pneumoconiosis in general and acute silicosis in particular.INTRODUCTIONThis communication summarizes our electron spin resonance (ESR) investigation of the formation of oxygenated radicals by freshly crushed quartz particles in a cell-free aqueous medium, and its potential role in the biochemical mechanism of acute silicosis. This study was undertaken because the mechanisms by which the quartz particles exert their toxic action on cells and the process(es) by which these actions progress to fibrogenesis are still not well understood. 1-3 It is generally believed, however, that the action of quartz particles on the cell membrane is the starting point of the silicotic process. 1,4 Since the first step must involve surface reactions, characterization of the chemical structure of the surface of quartz particles has been the subject of several recent studies!-' For example, we reported that mechanical crushing of quartz under normal atmosphere generates silicon-based (Si• and SiO•) radicals which decay with time, and that these radicals are associated with a higher cytotoxicity of fresh quartz dust as compared to that of an aged dust from the same stock. 6,8 Independently Fubini and coworkers' have also reported on the formation of Si• and SiO• -type of radicals from quartz particles crushed under atmospheric conditions. Gulumian and van Wyk9 have reported that quartz particles react with hydrogen peroxide (H202) to generate hydroxyl (•OH) radicals. These authors9 suggested that this process might contribute to quartz's pathogenicity but the mechanism of the -OH radical formation was not clarified. Earlier, Gabor and Anca10 had suggested that the cytotoxicity of quartz particles might be associated with the generation of some factor or factors possessing the properties of a free radical and hence capable of promoting the peroxidative chain cleavage of polyunsaturated fatty acid moieties of the phospholipids in the cell membrane. More recently, Weitzman and Graceffa 11 reported that asbestos is able to catalyze the generation of -OH radicals from H2O2. Their later work12 indicated that lipid peroxidation might be one of the mechanisms of tissue injury by asbestos."

Jan 1, 1989

By E. P. Youngman

Prior to 1854 the provincial legislatures in Austria enacted their own mining laws. The confusion that resulted from the existence of different codes when mining began to be conducted by modern methods forced the drafting of a law to cover all mining operations of the country. Such a general law (allegemines österreichisches Berggesetz) came into effect May 23, 1854, in the old monarchy, with the exception of Hungary, which had its own special laws. This general law of 1854 is still the basic mining law for Austria, although it has been amended and supplemented by a mumber of acts.

Nov 1, 1931

By H. Kenworthy

The investigations described in this report were undertaken to demonstrate, on a laboratory scale, the possibility of recovering several million pounds of tin plus tungsten contained in stockpiled and currently rejected slags from the Longhorn tin smelter at Texas City, Tex. At the same time, it was anticipated that the treatment procedures developed might be applicable to slags from other tin-smelting operations. Results of the laboratory work show that it is possible, by pyrometallurgical means, to separate the tin and tungsten into products of intermediate grade that may be returned to the smelter circuits for further upgrading. Several methods of treatment were investigated. The methods that proved effective were: Fusion reduction, chloride volatilization, sulfide volatilization, and carbide formation. Over 90 percent of the tin and tungsten could be removed from the slat by any of these methods. Each type of treatment has advantages and disadvantages, and it could not be determined from the small-scale work which method was the more meritorious. Tungsten and (in some types of treatment) tin-bearing products were diluted by iron, the separation of which will require additional studies. Prevention of a portion of the iron from reporting with the tin or tungsten is a distinct advantage and possibility that will require inure laboratory work to develop the needed techniques for its accomplishment. Tin products from single treatments of stag ranged up to 75 percent in tin content but were more generally under 35 percent. Tungsten products were usually under 15 percent; but segregated portions could be selected, at a sacrifice in recovery, that contained up to 50 percent tungstic oxide equivalent.

Jan 1, 1957

By J. D. Ramsdell

The purpose of this investigation was to determine the effects of the impurities, oxygen, nitrogen, carbon, and iron (in low percentages) on the mechanical properties of electrolytic titanium. The strength and hardness of binary Ti-O, Ti-N, and Ti-C alloys are linear functions of alloy content in the composition range investigated. Compared to oxygen and carbon, nitro-gen is the most effective strengthener and hardener, followed by oxygen, then carbon. When the carbon concentration is above 0.10 percent, carbides are present, and strength and hardness are relatively unchanged. For equivalent hardness levels, Ti-Fe alloys are stronger than binary titanium alloys containing oxygen, nitrogen, or carbon. However, the strengthening is related to the presence of transformed beta in the structure.

Jan 1, 1960

By K. E. Tame

A resume of the history and state of the art of physical beneficiation of uranium ores is presented along with a detailed description of research on concentration of uranium ores by attrition grinding. The information on flotation, gravity concentration, electronic sorting, and selective grinding was gathered to complement the study of attrition grinding methods. Both dry and wet grinding procedures were investigated as potential methods of upgrading a variety of ore types, ranging in grade from 0.02 to 0.42 percent U308. A Mardun4 disintegrator that employs high-speed rotating paddles in a cylindrical shell lined with interrupter bars was used in most of the dry grinding studies. Attrition scrubbing devices, which impart a violent mixing or attritioning action to ore pulps, and cylindrical mills, employing rods or punchings as grinding media, were used in the wet grinding tests.

Jan 1, 1961

By H. S. Caldwell

The objective of this investigation by the Bureau of Mines was to develop and test for laboratory use a retort embodying many features required for practical commercial-scale applications of vacuum distillation of metals. A gas-fired vacuum retort was developed comprising a hollow, cylindrical graphite liner encased in a thin shell of stainless steel. The liner prevents the shell from collapsing under vacuum and protects it from corrosion by metal vapors and the molten metal charge. The vacuum-tight shell protects the liner from oxidation and flame erosion. The retort was used to distill zinc from dross and die-casting scrap. More than 99 percent of the zinc was recovered as a condensate containing 99.8 to 99.9 percent zinc. (Atmospheric distillation recovers 95 to 98 percent at a purity of 99.5 percent zinc.) Distillation rates of 50 pounds of zinc per hour were attained at a temperature of 65° C. with pressures ranging between 50 and 100 microns. Distillation at this low temperature is not practicable at atmospheric pressure. Also, the retort is suitable for distilling other volatile metals such as cadmium and magnesium.

Jan 1, 1961

The principal activities of the Bureau of Mines Explosives Research Center from July 1, 1963 to June 30, 1964 are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1964; in general; the research reported in these publications antedates the report period. Part 3 describes a short-term investigation into safety problems associated with shipping of molten sulfur; this investigation is not at present destined for publication elsewhere.

Jan 1, 1965

The principal activities of the Bureau of Mines Explosives Research Center from July 1, 1963 to June 30, 1964 are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1964; in general, the research reported in these publications antedates the report period. Part 3 describes a short-term investigation into safety problems associated with shipping of molten sulfur; this investigation is not at present destined for publication elsewhere.

Jan 1, 1965

By T. E. Gray

This report describes the preparation characteristics of the more significant coal beds in Allegheny County, Pa. It is one of a series planned to determine coals suitable for producing metallurgical coke, either as mined or after beneficiation. More than 7 million tons of coal was produced in Allegheny County in 1957. Of this, more than 5 million tons was cleaned mechanically in nine cleaning plants. The Bureau of Mines estimated that, as of January 1, 1953, more than 384 million tons of recoverable coal remained in the county in beds 28 inches or thicker.

Jan 1, 1959

Develop a 22-ton capacity temporary mine roof support light enough to be easily lifted and transported manually from one place to another. Approach Several potential approaches were investigated in developing a new temporary support. An all-hydraulic, high-strength aluminum design was chosen as the best. The support was designed, fabricated, and tested in several mines. The first units, built for 6- to 8-foot seam heights, have a load- bearing capacity of 22 tons, and weigh only 55 pounds. How It Works The lightweight hydraulic support is designed for use in any temporary support situation in place of wood posts or steel mechanical or hydraulic supports. This includes use prior to roof bolting in room and pillar mining and in longwall development sections, use as head and tailgate supports for a longwall, and use as turn posts and breaker posts in retreat mining operations. The supports feature a release valve for quick manual extension to roof level, a lanyard

Jan 1, 1983

By S. R. Rannels, D. E. Rannels

"I. IntroductionThe alveolar surface of the lung is covered by two populations of pneumocytes, type I and type II epithelium. The type I cell, which accounts for most of the alveolar surface area and provides a highly specialized barrier for gas exchange (Rannels et al., 1991), is poorly understood. Although approaches to type I cell purification have been discussed, they have not been applied widely because of the lack of phenotypic markers to monitor isolation procedures (Dobbs et al., 1988; Danto et al., 1992). In contrast, the type II cell has been studied extensively, largely because of the development of reliable procedures for its isolation and primary culture. Investigations based on the use of purified populations of cultured type II cells have provided convincing evidence to support a role for the pneumocytes both in the maintenance of normal lung function and in the response of the lung to injury (for review, see Rannels and Rannels, 1989).While type II cells can be isolated by a variety of approaches, the protocols used most commonly are modifications of the gradient method of Dobbs and Mason (1979) or of the panning method of Dobbs et al. (1986). Purification of the cells based on density gradient centrifugation is reliable and consistent, with yields of 30 to 40 X 106 type II cells per rat of 230 g body weight. Isolation procedures applied to a minimum of three to four rats provide the best results, as lower cell yields are common with the use of fewer animals. The protocol below is designed to obtain a maximal cell yield from the lungs of six rats.II. Materials and InstrumentationMaterialsCalbiochem: DNase I (Cat. No. 260912); Corning: culture flask, 75 cm2 #25115; Costar: culture plate, 24-well #3424; disposable serological pipette #4101; Elastin Products Inc: elastase #E-134; Falcon: cellulose nitrate membrane filter, 0.22 µm, #7105; conical tube, 50 ml, #2070; culture dish, 100 mm, #3003; culture plate, sixwell, #3046; Fisher: BaS04 , #B68-500; NaCl, #5271-3; NaHC03 , #5233-50; Fort Dodge Laboratories: pentobarbital, #1206-lE; Gibco: Dulbecco's minimal essential medium (DMEM), #430-1600EC; Hanks' balanced salt solution (HBSS), #310- 4185AG; Joklik's modified Eagle's medium (JMEM), #410-2300EC; HyClone Laboratories Inc: fetal calf serum (FCS ), # A-1115-L; I CN Biochemicals (Flow Labora tories): amphotericin B, #16-723-48; newborn calf serum (NCS), #29-121-54; try pan blue, # 19 5 5 32; Na/gene: Erlenmeyer flask, # 100-4116C; Pharmacia: Percoll, #17-0891-01; density marker beads, #17-0549-01; Sigma: gentam1cm sulfate, #G3632; penicillin/streptomycin, #P3539; trypsin inhibitor, #T9128; Tetko: HC- 160 nylon mesh, #3-160-53."

Dec 1, 1995

By Raymond B. Ladoo

The uses for which ground talcs are suited closely depend upon their physical and chemical properties , but , in spite of this fact , little scientific investigation has been made in order to devise quick and accurate tests for the determination of these properties . The chemical properties of talc are inherent and may not be altered or modified except by selective mining or by chemical processes not practical in the present status of the industry . However , the determination of chemical properties is not so important , for most uses , as of physical properties , although sometimes certain chemical characteristics are perhaps unduly insisted upon by chemists in some industries . Physical properties are dependent both upon mineralogical characteristics and upon methods of grinding and sizing and may thus be partly changed or modified by changes in practice . There is so little known of the chemistry and physics of the various processes in which talc is used that the purchase and sale of talc is governed more by rule- of- thumb methods dependent upon individual opinion and often , prejudice , than by accurate , standard tests . This not only causes unwarranted price fluctuations , but injures both the producing and consuming industries by creating false ideas of the suitability of talc for various uses . It thus seems important that present tests be standardized and made uniform for the whole industry , and that new tests devised to fill the existing gaps .

Jul 1, 1920

By D. S. Kingery

The practice of using doors to control main ventilating currents in bituminous-coal mines is common throughout the industry. When doors are erected in pairs to form air locks, they are usually accepted as satisfactory by both State and Federal coal-mine-inspection agencies. A review of the contributing factors in recent methane ignitions showed that interrupted ventilation (often caused by doors latched open, destroyed, or damaged) was the principal cause of methane accumulations that subsequently were ignited.

Jan 1, 1958

By H. L. Riley, B. W. Gandrud

"INTRODUCTION The Bureau of Mines, United States Department of the Interior, with the cooperation of the University of Alabama and coal producers, has made a series of washability studies to obtain technically and commercially important data regarding the productive coal beds of the State. Based on the system followed in these studies, this report consists principally of screen-sizing and float-and-sink data on the Clark and Gholson beds at Boothton, Ala. A previous washability study 4/ has been made on the Clark bed at Marvel, Ala.SAMPLING AT MINESThe coal from the Gholson and the Clark beds was sampled at the tipple which receives the output,the Boothten No. 3 and No. 4 mines. These two mines are on the Gholson and Clark beds, respectively, but the coal. from both mines is mixed on the tipple and washed in the same washery. The samples taken were minus 4-inch raw coal. The plus 4-inch raw coal is hand¬picked and not washed. AS the 4-inch screen had a capacity in excess of the output of the mines, it was stopped at the end of each mine-car trip. By Observing from which mine incline each trip was hoisted, a separate sample from each bed was cut from the discharge stream of an endless belt which conveys the through 4-inch raw coal to the bin ahead of the washer. The output from each bed was sampled uniformly over the period of a working shift. The two washability samples weighed approximately 3,000 pounds each."

Dec 1, 1947