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By Edward D. Thimons

The Bureau of Mines has developed a damage-resistant brattice, intended for use as a stopping in locations where blast damage to stoppings is a problem, the roof is relatively flat, and the differential pressure across the stopping is not high. Damage-resistant brattices consist of a series of vertically hung brattice panels joined to each other by Velcro connections that improve the airtightness of the brattice. When the brattice is subjected to strong blast forces, the Velcro connections peel apart, allowing the panels to open without incurring damage. The Velcro connections can then be resealed in a matter of minutes. A preliminary test in the Bureau's Safety Research Mine and subsequent long-term testing at the White Pine copper mine in Michigan and the Retsof salt mine in New York show that damage-resistant brattices withstand blasting better than conventional stoppings, while still performing as efficient air barriers when the Velcro connections are sealed.

Jan 1, 1978

By James A. West

The South Asian countries of India, Pakistan, Afghanistan, Ceylon, Nepal, Bhutan, and Sikkim arc to varying-degrees just beginning to achieve significant economic and industrial development. These countries are richly endowed with certain mineral resources, and development of these resources is being accelerated. In 1965, the mineral industry remained a relatively small sector of the region's economy, accounting for only about 1 percent of its estimated gross national product of $62,528 million. Nevertheless, the estimated $630 million total value of minerals produced in South Asia during 1965 represented an increase of nearly 15 percent t over that of 1964. India continued as the dominant mineral producer of the region, accounting for 85 percent of the total value of all minerals produced ill 1965. India increased its output of iron ore, manganese, mica, coal, and petroleum. Pakistan accounted for 13 percent of the value of the region's output and recorded increased output of iron ore, chromite, coal, natural gas, and most other minerals. The small mineral industry of Ceylon attained remarkable growth in the production of ilmenite, graphite, and gem stones. The mineral industry of Afghanistan remained relatively insignificant, although development of large known resources of natural gas was continued, Nepal, Bhutan, and Sikkim produced no commercially significant quantities of minerals in 1965.

Jan 1, 1967

By D. J. Bauer

The Bureau of Mines has conducted extensive studies on the recovery of alumina from kaolinitic clay by a HCI leaching-HCI sparging process. The current study reports a modification of the process, which involves a double-leaching system. The first leach of the calcined clay is made at as high a HCI acid strength as possible so that the dissolution of aluminum chloride hexahydrate (AlCI3*6H20) is suppressed, Most of the impurities, but very little aluminum, are soluble in the strong acid. After liquid-solid separation and washing, the solids are leached with recycled weak HCI, which dissolves the AICI3'6H2O. The pregnant liquor is separated from the gangue, and AICI3'6H2O is crystallized from solu-tion by injecting HCI gas. A proposed flowsheet is presented, and the effect of bleedstream size on AlC13'6H20 purity is discussed.

Jan 1, 1984

By M. J. Ankeny

This is a study of 58 fatal haulage accidents investigated by Federal coal-mine inspectors during the period January - June 1951. The information presented in this circular was obtained by analyzing fatal haulage accidents in 33 bituminous-coal producing counties representing 11 States. The physical conditions represent a cross section off producing coal beds. Mining and transportation methods vary, from those of small hand-loading mines to those of large modern mechanized operations. These data are thought to be representative of haulage conditions within the bituminous-coal mining industry and are submitted to follow up the Information Circular 7604 ?Analysis of Haulage Fatalities in Bituminous-Coal Mines - 1950.? Coal-mine haulage ranks second as a cause of coal-mine fatalities, and the problem of haulage safety is complex. It is subject to constant change and is comprised of numerous influencing variables, which are not always obvious. The solution to this problem will not come through the application of any standard formula or mechanical approach since the inherent factors are strongly influenced by the human equation, and the chain of circumstances is further affected by expediency.

Jan 1, 1951

By J. T. McCartney

"INTRODUCTION The surface areas of the finest fractions of a pulverized material are disproportionately larger than their weights. For instance, Pesrott and Kinney 3/ showed that, in a sample of minus 200-mesh coal, particles that are about 2 microns in diameter represent 15 percent of the entire surface area but only 1.5 percent of the total weight. Because the sur- face area is the dominating factor in the behavior of finely divided materials in many practical processes, the role of the finest particles is of great importance. The oxidation and combustion of pulverized coal, both in the dry form and in suspension in oils, and the hydrogenation to fluid hydrocarbons of mixtures of pulverized coal and heavy oil are reactions in which the surface area of the coal particles has considerable influence. This investigation of the size distribution of fine coal particles was conducted with the hope that such processes would thereby be better understood. The results should also be of value in the study of the crushing and fracture of coal."

Sep 1, 1945

By Diane Schwegler-Berry, Vincent Castranova, Chang-geng Moe, Jane Y. C. Ma, Mark D. Moore, Joseph K. H. Ma, Carl J. Malanga, Ji-Hee Kane

"Effects of Bisbenzylisoquinoline Alkaloids on Alveolar Macrophages: Correlation between Binding Affinity. Inhibitory Potency and Antifibrotic Potential. CASTRANOVA, V., KANG, J-H., MA. J. K. H., Mo, C-H., MALANGA, L. J., MOORE M. D., SCHWEGLER-BERRY, D.. AND MA. J. Y. C. (1991). Toxicol. Appl. Pharmacol 108, 242-252. The Chinese have conducted extensive studies concerning the medicinal properties of plant products. In this investigation the ability of three bisbenzylisoquinoline alkaloids to inhibit particle-induced activation of alveolar macrophages was evaluated and this inhibitory potential was correlated with the ability of those drugs to bind to membrane components. Tetrandrine. i.e.. an herbal medicine used as an antifibrotic agent in China, was a potent inhibitor of particle-stimulated oxygen consumption, superoxide release, and hydrogen peroxide secretion by alveolar macrophages. Tetrandrine also exhibited substantial binding affinity for membrane lipids and alveolar macrophages. In contrast, tubocurine, an analogue with little antifibrotic potential, exhibited low binding affinity and had little effect on macrophage activation. Methoxyadiantifoline, an alkaloid of unknown antifibrotic potential, exhibited inhibitory and binding properties similar to those of tetrandrine. The data indicate that a strong relationship exists between the antifibrotic potential of these alkaloids and their ability to bind to alveolar macrophages and inhibit particle-induced activation of these phagocytes. These drugs should serve as useful probes to evaluate the role of alveolar macrophages in pulmonary fibrosis. © 1991 Academic Press, Inc.Chronic silicosis is a fibrotic disease resulting from occupational exposure to silica dust. It is manifested initially by an increase in the quantity of pulmonary surfactant (Dethloff et al., 1986). However, in later stages it is characterized by an increase in collagen formation and the development of concentric hyalinized nodular lesions in the lung (Ziskind et al., 1976). Although mechanisms for the progression of silicosis have not yet been completely defined, activation of alveolar macrophages by respirable silica particles is believed to play an important role in the etiology of this disease. Studies from our laboratory have shown that both in vitro and in vivo silica exposures result in a stimulation of macrophage release of reactive products capable of damaging the lung parenchyma (Castranova et al., 1990; Goodman et al., 1990). In addition, exposure of al¬veolar macrophages to silica results in the release of fibrogenic factors which enhance the proliferation of fibroblasts and the synthesis of collagen by these pneumocytes (Leibovich and Ross, 1976; Bitterman et al., 1982, 1983).The bisbenzylisoquinoline alkaloids, which represent the largest group among the iso-quinoline compounds isolated from the plant kingdom, are known to exhibit a broad rangeof pharmacological activities. Tetrandrine, for example, an alkaloid isolated from the root of Stephania tetrandra, has been tested for its antitumor, antihypertensive, and antisilicotic effects (Kupchan and Atland, 1973; Zeng et al., 1985; Yu et al., 1983). It is currently used in China as a treatment for angina, hypertension, and silica-induced pulmonary fibrosis (Li et al., 1981). Several related bisbenzylisoquinoline alkaloids such as methoxyadiantifoline and tubocurine have also been evaluated for medicinal effects. Methoxyadiantifoline has been shown to exhibit effects on the cardiovascular system similar to those reported for tetrandrine (Jia et al., 1988). However, to date, the antifibrotic activity of methoxyadiantifoline has not been evaluated. In contrast to tetrandrine, tubocurine, a structural analogue of this drug, has been reported to be relatively ineffective against fibrosis (Mo et al., 1982)."

Mar 1, 1992

By D. J. MacDonald

This U.S. Bureau of Mines report reviews published information on synthetic berlinite (AlP04) and suggests experimental conditions requisite for its production. Berlinite is a piezoelectric material with potential use as a substitute for quartz in the crystal oscillators, which are components of electronic and electroacoustic equipment. Information gathered here (mostly from published sources) includes historical background, physical properties, end-use applications, criteria of quality, and physio-chemical factors involved in berlinite crystal growth. It is concluded that growing large high-quality berlinite crystal would require high-purity starting materials in an autoclave equipped with a noncorrodible liner and operated with temperature control of ±O.OO5 ac over a range of 250 to 350 ac.

Jan 1, 1995

By T. H. Jeffers

The U.S. Bureau of Mines has developed porous beads containing immobilized biological materials such as sphagnum peat moss for extracting metal contaminants from waste waters. The beads, designated as BIO-FIX beads, have removed toxic metals from over 100 waters in laboratory tests. These waters include acid mine drainage (AMD) water from mining sites, metallurgical and chemical industry waste water, and contaminated ground water. Following the laboratory studies, cooperative field tests were conducted to evaluate the metal adsorption properties of the beads in column and low-maintenance circuits, determine bead stability in varied climatic situations, and demonstrate the beads' potential as a viable waste water treatment technique. Field results indicated that BIO-FIX beads readily adsorbed cadmium, lead, and other toxic metals from dilute waters; effluents frequently met drinking water standards and other discharge criteria. The beads exhibited excellent handling characteristics in both column and low-maintenance circuits, and continued to extract metal ions after repeated loading-elution cycles. Based on laboratory and field data, cost evaluations for using BIO-FIX technology to treat two AMD waters were prepared. Operating costs for BIO-FIX treatment, which ranged from $1.40 to $2.30 per 1,000 gal of water treated, were comparable with chemical precipitation costs.

Jan 1, 2010

By Mah Alla D.

Previously existing heat-of-formation values for the oxides of vanadium were rudimentary. They were subject to uncertainties of 1 to 5 kilocalories per gram-atom of contained oxygen. This fact has been the only adverse influence on the accuracy of thermodynamic calculations involving these substances, as the requisite entropy and high-temperature heat-content data are known with reasonable accuracy. This report presents new heat-of-formation data for four oxides of vanadium (VO, V203, V02, and V205), obtained by combustion calorimetry. It is believed that the uncertainties have been reduced to 0.1 to 0.3 kilocalorie per gram-atom of contained oxygen. The new heat-of-formation data were combined with existing entropy and high-temperature heat-content values to obtain free energies of formation of the four oxides at temperatures up to 2,000° K.

Jan 1, 1961

By John Nagy

Results of initial research by the Bureau of Mines are given on the dust explosion hazard of float coal and on the related factors of occurrence, rate of production, sampling techniques, transport, and deposition of float coal. Tentatively, it is suggested that where float coal deposits prevail, a mini-mum of 80 percent incombustible be maintained in the top 1/8-inch layer to neutralize the explosion hazard of the surficial coal deposit.

Jan 1, 1965

By D. D. Fischer

Recovery and separation of molybdenum and rhenium from a process solution was accomplished by a technique developed by the Federal Bureau of Mines involving a combined solvent extraction and activated carbon adsorption procedure. The processing sequence required treatment of the solution with S02 to reduce the chlorate ion and adjust the pR prior to solvent extraction of molybdenum and rhenium with a tertiary amine. Molybdenum and rhenium were stripped from the organic phase with an NH40H solution, and the strip solution was then passed through activated carbon to preferentially adsorb the rhenium. After washing entrained molybdenum from the column with a brine solution, rhenium was eluted with an MeOH-H20 mixture. The activated carbon was regenerated with water. Molybdenum was recovered as (NH4)6Mo7024 by evaporating the column effluent. Rhenium in the column eluate was reextracted with a tertiary amine, stripped from the organic phase with dilute NH40H, and recovered as NH4Re04 by evaporating the strip solution. The final (NR4)Re04 product contained < 80 ppm impurities. Sodium sulfate was crystallized from the first solvent-extraction raffinate by lowering the solution temperature to 0° C. Precious metals contained in the original process solution were adsorbed onto the activated carbon.

Jan 1, 1975

By J. R. Hauger, P. A. Romans, W. J. Niebuhr

With suitable instrumentation and techniques it is possible to determine the presence of tantalum in columbium to 20 ppm . This paper discusses the selection of X- ray spectrographic instrumentation and describes a technique for accomplishing the low level determination of tantalum . An ion- exchange method of separating tantalum from columbium is also described .

Jan 1, 1964

By R. V. Ramani, A. S. C. Owili-eger

List of Numbers

Jan 1, 1974

By D. B. Dow

This paper on the physical chemistry of oil-field emulsions is the last of a series of three prepared as a result of a study of oil-field emulsions. The first paper3 deals with the factors responsible for the formation of emulsions, find the second4 with methods now utilized for dehydrating oil-field emulsions. A more complete report of the whole investigation is in preparation. The laws governing the formation and resolution of oil-field emulsions fall in that branch of physical chemistry doling with colloids. Much work has been done by the physical chemist on colloids And emulsions, and, although most of this work was on commercial and pharmaceutical emulsions, yet the principles developed apply in a general gray to oil-field emulsions.

Jan 1, 1925

By R. Hogg

"The problems of sampling particulate materials, and of characterizing the distributions of particle size and composition are reviewed. Requirements for sampling from comminution systems are discussed and a simple formula is presented for estimating the minimum sample size needed. The limitations and errors associated with the techniques available for particle size analysis are evaluated and guidelines are suggested for the selection of appropriate methods. The use of microscopic and macroscopic approaches to the characterization of particle composition are discussed.INTRODUCTIONComminution is a process of particle size reduction in which the goal is to produce a material with a specified particle size distribution from a coarser feed. In mineral processing applications, the product size distribution is often qf secondary importance to the extent to which individual mineral grams can be liberated from one another. However, due to poor understanding of the nature of the liberation process and the lack of reliable procedures for characterizing it, the actual specification is normally in terms of particle size.Particle size distribution can be regarded as the fundamental characteristic of a particulate system. The distributions of particle shape and composition among the various particle sizes present are often sufficient to define the bulk properties and behavior of the system. Description of the distributions of size; shape and composition of the different phases which may exist within individual particles is necessary to complete the picture and is especially important for predicting liberation etc., in comminution processes. It is quite obvious that · the complete characterization of real particulate systems is a formidable, if not .impossible task. Practical characterization procedures should involve ·evaluation of those characteristics which are deemed to be important and which can be measured. In comminution systems, this should ideally include the particle size distribution, the size-by-size distributions of particle composition, and as much information as can be acquired on the internal composition and structure of individual particles. In most cases, of course, we fall far short of even this rather limited goal."

Jan 1, 1988

By G. R. Hopkins

The petroleum-refining industry established a new record in fuel efficiency at refineries in 1936, when 597,000 B. t. u. of heat were required to refine a barrel of crude oil, compared with an average of 615,000 B. t. u. in 1935 (see fig. 1). The principal factor in the "indicated gain in fuel efficiency at refineries in 1936 was an increase in crude runs of 11 percent over 1935. A large part of the heat utilized at refineries is consumed elsewhere than under stills, or in ways quite independent of crude-oil distillation. In other words, as the operating ratio (crude runs divided by capacity) for refineries increases toward the maximum of 100 percent, the fuel requirements show progressively smaller increases and the average E. t. u. consumption per barrel of crude refined declines.

Jan 1, 1938

By Chester L. Arnold, Reinhardt Thiessen, Alexander Lowy

"INTRODUCTION Peat is the accumulated mass of plant materials that remain after partial decay under specific conditions. In the swampy peat bogs dead material which falls on the surface immediately is attacked by fungi and aercbic bacteria. Decay under these conditions is rapid, but of relatively short duration, since the constant addition of new material soon forces the older layers below the water level, in this position, without access to oxygen, the plant constituents are attacked mainly by anaerobic bacteria, and decomposition proceeds slowly. The largest part of peat is contributed by the woody tissues of plants, the chief constituents of which are cellulose and lignin, together with a small proportion of hemicelluloses. During the normal process of biological decay celluloses disappear more rapidly than lignin. The result is a complex substance known as humin, from which the humic acids may be extracted.In 1826, Sprengel 5 found that when decayed plant materials were extracted with alinnli and the resulting black liquid acidified with mineral acid a brown gelatinous precipitate was formed. To this product, which was a brown amorphous powder when dry, he gave the name ""humic acid'. Since that time, chemists have used the name rather loosely to designate products which have been isolated by very diverse means from soils, decayed woods, peat, lignite, and coal. An excellent review of the early work on humic acids was published by Baumann 6 in 1909. This publication aroused the interest of Oden, who then investigated the humic acids. An account of Oden’s work, as a good survey of the literature, is contained in his monograph “Die Huminsauren”. 7"

Nov 1, 1934

By D. J. Bauer

A solvent-extraction system employing selective stripping of a pre loaded organic phase was investigated for recovering Sm203 from a light-group rare-earth mixture. The samarium concentrated in the organic phase, and a >99-pct-pure samarium oxide product was obtained at 76-pct recovery in a 20-stage operation using di(2-ethylhexyl) phosphoric acid (EHPA) as the organic phase. The stripping agent was a 1.5-pct hydrochloric acid solution containing 200 g NH4C1/1.

Jan 1, 1972

By Theodore Kootz

Manufacture of high-grade ferromanganese; as a rule; requires a low-phosphorus-manganese ore with 45 to 55 percent Mn, chiefly obtained in the Soviet Union, the British Dominions, and Brazil. Also, low-manganese ores have already been used for ferromanganese production, especially in North America .and Germany. During World War I, a process was developed in which a high-phosphorus ferromanganese or spiegeleisen was prepared in the blast furnace from law- or high-phosphorus manganiferous ores, then low-phosphorus manganese slag was prepared by refining under an acid slag, and this material was, worked into a low-phosphorus ferromanganese in the blast furnace.9/ Manufacture of useful manganese ores from a phosphorus-bearing spiegel with 12 to. 15 percent Mn, 4.5 percent C,, and 0.5 percent P by slagging in a refining furnace was reported by Joseph, Barrett, and Wood.10/ The spiegel was refined to 0.75 percent Mn, 3.4 percent C, and 0.45 percent P. Thereby, a slag with about 43 to 58 percent Mn and, about 10 percent Si02, was obtained. Hotter melts gave a smaller phosphorus content in the slag than cold melts. In addition, the phosphorus content of the slag varied with the manganese content of the intermediate metal.

Jan 1, 1952

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