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By C. H. Fisher

Sulphuric acid of various concentrations has long been used as a reagent in the determination of olefins and aromatics in hydrocarbon oils4 such as gasoline, kerosene, and neutral oils from coal-tar distillates. Despite its long use, however, there is no general agreement as to optimum conditions and concentration of acid, and numerous methods and modifications have been recommended. In most cases, treatment of the neutral oil with 80 to 90 percent sulphuric acid, followed by distillation to the original endpoint to remove olefin polymers, is recommended for the estimation of unsaturated hydrocarbons. The distillate thus obtained is taken as olefin-free oil and used in later stages of the anlysis. Aromatic hydrocarbons generally are determined in the olefin-free oil by suphonation with more concentrated acid (96 to 100 percent and fuming sulphuric acid are recommended), the hydrocarbons not attacked and removed as water-soluble sulphoric acids being considered as saturated hydrocarbons. In some cases the saturates are examined further by differentiating between cyclic (naphthenes) and acyclic hydrocarbons (paraffins), Generally this is achieved by physical methods, although strong sulphuric acid is known to react preferentially with some types of saturated hydrocarbons. It was the purpose of the present work to make a general study of this type of analysis and to investigate the reactions of hydrocarbons under conditions often used in analyses that employ sulphuric acid reagents. Since previous work is not in good agreement, the optimum concentrations of acid for the different stages of the analysis were determined. Several sulphuric acid methods previously recommended and new modifications were compared, two synthetic solutions being used as the reference oil. The results obtained are presented below under separate headings.

Jan 1, 1937

Objective To develop and evaluate the effectiveness of safety training tools specific to underground metal/nonmetal mining. Background In a series of stakeholder meetings held in the western United States beginning in 1998, participants identified a critical lack of appropriate training materials applicable to metal/nonmetal mining. Participants in the meetings provided many insights into what types of training materials are most effective in dealing with both experienced and inexperienced miners. Most important was that the materials should be realistic and interesting and that some way should be found to capture the wisdom and expertise of older miners before they retired. In response, training videos that focus on safe practices during the mining cycle are being produced. Two videos one on handling explosives underground and one on identifying roof hazards and proper scaling techniques were completed during1999, and a third video is now available. This video, entitled “Ground Support...It’s Important, or Miner Mike Saves the Day,” presents information on why ground supports work and how to install them properly. Approach The new video, “Ground Support…It’s Important,” presents a scenario in which two young miners make a bad decision to leave some supports out in order to catch up in their mining cycle. An expert miner, “Miner Mike,” sees this potentially disastrous situation and educates the young miners about what could happen if they continued to leave supports out. He introduces the young miners to several expert miners, who explain how to install different types of supports correctly, as well as share what experience has taught them over the years. How It Works All footage was taken in operating, underground mines, using14 experts to provide the teaching. Because of the wide variety of supports used underground, it was necessary to focus on those types more common to hard-rock mining. While more complex support systems, such as shotcrete and cable bolts, are mentioned, detailed material is not included. In the course of educating young miners Jeff and Jason, Miner Mike provides information on— •Why supports are necessary in underground mines. •The main types of supports commonly used in underground hard-rock mines. •How supports work. •How holes for bolts are drilled correctly using jacklegs, drill jumbos, and bolting jumbos.• How wire mesh, wire panels, metal mats, and different types of bolts, including mechanical bolts, friction bolts, grouted bolts, and cable bolts, are installed properly. •How to recognize that supports have failed and what to do about it.

Jun 1, 2000

By W. P. Haynes

To evaluate the potential use of battery-powered vehicles, the Bureau of Mines studied the performance of a battery-powered truck propelled by a 9.6 kw dc motor in considerable detail under various driving conditions. Some of the factors investigated were: Gear ratios, payload (1,468 lb maximum), road grade, stops made per mile, and charging time. With the exception of some difficulty with brush wear, operation and maintenance of the truck was generally trouble-free. On range tests carrying an 868-lb payload a distance of about 50 miles at an average speed of about 19 mph in normal driving, the Bureau's battery-powered truck averaged 1.6 to 1.9 miles per ac kwhr input. Stop-and-go tests indicated that prospects for the use of battery-powered trucks in house delivery service within city limits are good; performance of the Bureau truck was sufficiently high for that type of service. The estimated power cost of 2.65 cents per mile while making 10 stops per mile was attractively low from the standpoint of fuel costs.

Jan 1, 1967

By Burton J. Thamer

Radon emanation coefficients of 0.02 to 0.55 were measured at moisture contents ranging from dry to saturation in eighteen different ores. The emanation coefficients rose from a minimum when dry to a plateau usually starting at 5-20 percent of saturation. A model, using measured pore-size distributions, suggested that the radium mineralization may be confined to annular layers about 0.02 micrometers thick around pores. Radon's diffusion coefficient was determined as a function of moisture. The techniques involved comparing a disc's exhalation as a function of time whether or not the disc had a distributed source. The model was free of approximations and included the effects of porosity and adsorption. An increase of diffusion coefficient with moisture for one or two ores was explained in terms of a model's equation for the diffusion coefficient in terms of both volume and surface diffusion. Radon's adsorption coefficient was determined on a uranium ore.

Jan 1, 1981

By C. O. Ruud, R. E. Siemens, D. Chandra

The mineralogical constitution of a lateritic ore dictates the type of metallurgical process that can be used to extract valuable metals such as nickel and cobalt . To provide needed mineralogical information on the interrelationships of the metals contained in domestic laterites , the Bureau of Mines awarded a grant to Denver Research Institute to study the transition - type , low - grade laterites found in northern California and southern Oregon . For comparison , limonitic - type laterites from New Caledonia and the Philippines were also studied . X-ray diffraction , electron microscopy , electron beam analysis , and conventional petrography were used to determine the mineralogical associations of nickel and cobalt in the laterites . Results showed that for both laterite types studied most of the nickel and minor amounts of cobalt are associated with the mineral geothite ( FeO ( OH ) ) . Most of the cobalt and minor amounts of nickel are associated with a mixed manganese oxide (wad ) mineral .

Jan 1, 1983

By Leland H. Johnson, D. O. Kennedy, John Hyvarenen

"SUMMARYA chronological list of accidents at metal and nonmetal mines and quarries (excluding coal mines) in the United States in which five or more lives were lost has been compiled. Many accidents were described in more detail because of their unusual features. Tables have been included to indicate the number of major disasters and fatalities by the principal product mined, by State, and by 10-year intervals prior to 1945. The number of men employed to indicate man-hours exposed is unavailable; therefore, a true picture of disaster data by principal product mined, by State, and by 10-year intervals is not possible. However, the data are presented to indicate the causes of major accidents and bring to the attention of those affiliated with metal and nonmetal mines and quarries the hazards involved and lessons that can be practiced to keep such accidents at a minimum.INTRODUCTIONThe Bureau of Mines was requested to compile a chronological list of accidents at metal and nonmetal mines and quarries (excluding coal mines) in the United States in which five or more lives were lost. Data have been assembled on accidents from all causes in these mines and quarries from the earliest available information (describ¬ing an underground mine fire in Nevada in 1869) to the last reported major accident (a fire at a company-owned bunkhouse in Arizona in 1945).The accounts of the accidents were taken from articles in the technical press and from published and unpublished reports of the Bureau of Mines. Many of the accidents have been selected for more detailed descriptions because of the unique circumstances and to show the variety of dangers involved.Tables are included to indicate the number of major accidents, with resultant fatalities, by the principal metal and nonmetal producing groups, by State, and by 10-year intervals previous to 1945. The interval 1869-1875 does not cover a 10-year span because of incomplete records previous to 1869.ACKNOWLEDGMENTSThe information contained in this report was obtained from the Engineering and Mining Journal from 1874 to 1947, the Mining and Scientific Press from 1908 through 1922, from various published and unpublished reports of the Bureau of Mines and from reports by State departments of mines. Daniel Harrington, retired chief of the Health and Safety Division; E. H. Denny, supervising engineer, District H; R. M. Loucks, mining engineer; and other engineers of the Division contributed much valuable information and assisted materially in the study."

Apr 1, 1949

By R. F. Abernethy

Recent investigations in the United States and in other countries have produced considerable information on the nature and occurrence of minor elements in coal. The possibility of recovering certain elements, particularly germanium and uranium, from coal ash and other coal products has received considerable attention. Some flue dusts are potential sources of germanium, and certain lignite deposits are potential sources of uranium, but industrial recovery of these elements has been limited to small quantities for technical and economic reasons. Considering the large amount of coal mined annually, a small percentage of a rare element may have industrial significance if an economical method of recovery can be developed. In 1944 information on the occurrence of rare elements in coal was reviewed in Bureau of Mines Technical Paper 669 (46).3 This report is a revision of that paper with the view of summarizing published information available for United States coals, and pertinent information concerning coals of other countries. Selected references from the original paper are retained. New references do not include all preliminary reports when more permanent literature describing complete projects is available. Consequently, the list of references should not be considered complete.

Jan 1, 1963

By M. C. Malamphy

A general description of the activities and results of bauxite investigation by The Bureau of Mines at its bauxite project in Saline and Pulaski Counties, Ark., has been given in Report of Investigations No. 4251. The factual data obtained during the project are reported in a series of Reports of Investigation beginning with No. 4251, of which this is the fourth. The data are accompanied by maps showing the location of holes drilled and the deposits developed. Each area upon which work was done is reported by half townships. Each bauxite deposit investigated was assigned a name and a number for ready reference and identification, and its location and name are shown on the appropriate half-township map. The description of each half township is followed by a description of each deposit developed in that half township. The 14 half-township maps and 77 detail maps of the bauxite deposits in this series of reports give the locations and numbers of all the holes drilled on the project except the deep holes drilled to test the geophysical anomalies. The locations of those holes show on Figure 13 in Volume 1. The descriptions of the deposits developed are followed by complete detailed logs of the drill holes. Many of the widely spaced exploratory holes did not discover bauxite of minable thickness and grade. The pertinent information obtained from the widely spaced exploratory drill holes has been summarized and tabulated, and a table for each half township-is given with the discussion covering that area.

Jan 1, 1948

By R. F. Tenney

This report has been prepared because little detailed information has been published on the production and use of anthracite producer gas for industrial-process and brick-kiln heating. To obtain this information, an investigation was conducted by the Federal Bureau of Mines in cooperation with a building-brick manufacturer (firing both periodic and tunnel kilns with anthracite producer gas) and with a manufacturer of anthracite-gas producers. In addition to a study of available plant records, 2 weeks was spent in systematic observation and measurement during regular operation of the Hazleton Brick Co. plant, Hazleton, Pa., in July 1953. This report presents the results of this investigation and a description of producer and periodic-kiln equipment, operating procedures, and labor requirements. A summary of the conditions of producer and kiln operation is given for the 2-week observation and for the 11 preceding months. The two 10-foot standard anthracite-gas producers consumed 301 tons of Rice and Buckwheat No. 1 anthracite, as delivered, averaging over 13,000 B.t.u. per dry pound during the 2-week period, with a producer hot-gas efficiency of 95 percent, at an average gas offtake temperature of 5400 F. The yield of gas5/ of 153 gross B.t.u. per cubic foot amounted to 140,000 cubic feet per ton of fuel as fired, or 73,500 cubic feet per kiln heating hour, which was sufficient for kiln requirements.

Jan 1, 1960

By Jos. R. Guiteras

This is one of a series of information circulars describing mining and milling methods being published by the Bureau of Mines. The Summitville Consolidated Mines, Inc., is the only company now active at Summitville. Since the holdings of the company include those of most of the former producers of the camp, the paper virtually becomes a description of the Summitville district. The field data were collected from August 23 to 28, 1937. ACKNOWLEDGMENTS The writer gratefully acknowledges his indebtedness to H. F. Detrick, president, and Edward Thornton, general manager of the company for their cooperation in making this paper possible. Most of the information on underground operations was given by Roy Jellison, mine superintendent; the metallurgical data were supplied by Art Carl son, metallurgist, and W. L. Anderson, mill superintendent; much general and technical information was supplied by J. H. Hannan, engineer.

Jan 1, 1938

By BUREAU OF MINES

PLATINUM

Feb 1, 1922

By C. H. Fisher

Sulphuric acid of various concentrations has long been used as a reagent in the determination of olefins and aromatics in hydrocarbon oils4 such as gasoline, kerosene, and neutral oils from coal-tar distillates. Despite its long use, however, there is no general agreement as to optimum conditions and concentration of acid, and numerous methods and modifications have been recommended. In most cases, treatment of the neutral oil with 80 to 90 percent sulphuric acid, followed by distillation to the original endpoint to remove olefin polymers, is recommended for the estimation of unsaturated hydrocarbons. The distillate thus obtained is taken as olefin-free oil and used in later stages of the anlysis. Aromatic hydrocarbons generally are determined in the olefin-free oil by suphonation with more concentrated acid (96 to 100 percent and fuming sulphuric acid are recommended), the hydrocarbons not attacked and removed as water-soluble sulphonic acids being considered as saturated hydrocarbons. In some cases the saturates are examined further by differentiating between cyclic (naphthenes) and acyclic hydrocarbons (paraffins), Generally this is achieved by physical methods, although strong sulphuric acid is known to react preferentially with some types of saturated hydrocarbons. It was the purpose of the present work to make a general study of this type of analysis and to investigate the reactions of hydrocarbons under conditions often used in analyses that employ sulphuric acid reagents. Since previous work is not in good agreement, the optimum concentrations of acid for the different stages of the analysis were determined. Several sulphuric acid methods previously recommended and new modifications were compared, two synthetic solutions being used as the reference oil. The results obtained are presented below under separate headings.

Jan 1, 1937

By J. L. Hoffman, F. W. Wood, R. A. Beall, W. E. Anable

For melting and purifying reactive and refractory metals , two electronbeam furnaces have been constructed and operated on the principle of highpowered vacuum diodes . It was necessary to design the vacuum and electrical systems , mechanical features , and operating procedures to cope with dynamic conditions . Vacuums of 10-5 torr , tens of kilowatts of power at 5 to 10 kilovolts , and the evolution of impurities at thousands of liters per minute constitute a challenging combination . The furnaces have been used to melt either button specimens weighing several hundred grams or , by feeding material as a consumable electrode , small ingots weighing several kilograms . Hafnium is among the metals that can be purified . For example , hafnium starting material with Rhn 94B was softened to Rhn 70B after 2 hours of melting under a 25 - kw electron beam , and impurity levels were reduced as follows : Oxygen , from 700 to 350 ppm ; nitrogen , from 71 to 20 ppm ; hydrogen , from 6 to 1 ppm ; aluminum from 75 to < 20 ppm ; chromium , from 80 to < 10 ppm ; iron , from 100 to 40 ppm ; and silicon , from 40 to < 20 ppm .

Jan 1, 1963

By T. R. Jolley

This publication describes the control of fires in inactive coal deposits in the Western United States, including Alaska by the Bureau of Mines. Material presented should contribute to a better understanding of the purpose, process, and benefits of the program. Forty fires were extinguished or controlled in the Western United States and Alaska from 1948 to 1958 under a national program directed by the Bureau&apos;s Health and Safety activity. Thirty-five fires were controlled by smothering; three were controlled by the isolation method; and two were extinguished by removing the burning coal, smothering it with incombustible material, and backfilling the fire zone. The fire-control projects were distributed as follows: Alaska 2, Arizona 1, Colorado 9, Montana 9, New Mexico 4, Utah 2, and Wyoming 13. The total cost of the 40 fires extinguished or controlled was $1,203,957. Of this cost, 12.8 percent was engineering and administrative and 87.2 percent was contractual services.

Jan 1, 1959

By Philip C. Good

Preliminary studies showed that direct hydrolysis of H2SiF6 to SiO2 and HF at elevated temperatures was subject to many mechanical difficulties, and that corrosion of construction materials was a serious problem. Elimination of SiO2 from the HF product was generally poor. An alternative procedure, hydrolysis of lime-neutralized H2SiF6 by steam at 950° to 1,100° C, yielded a product very low in SiO2. Condensates containing up to 300 g/1 HF were prepared.

Jan 1, 1968

By M. M. Tilman

As part of ongoing research to improve mine safety, the Bureau of Mines conducted research on the corrosion of friction rock stabilizer steels in five Missouri lead and iron mine waters. Electrochemical corrosion tests, including evaluation of pitting tendency, were performed on two types of high-strength, low-alloy (HSLA) steels and galvanized steel in four Missouri lead mine waters and one Missouri iron mine water. The tests were conducted at in-mine water temperatures in both air-saturated and deaerated waters. Static, weight-loss corrosion tests were also conducted on HSLA steel specimens in the five Missouri mine waters for 2,900-h duration at average in-mine water temperatures and air-dissolved oxygen contents of 6 to 7 ppm. Corrosion rates determined by the weight-loss tests were roughly comparable with rates determined electrochemically in deaerated waters containing 0.3 to 0.5 ppm dissolved oxygen content. Passivation of specimen (nongalvanized) surfaces in air-saturated waters resulted in very low electrochemically deter- mined corrosion rates. Pitting-tendency was generally higher for both HSLA steels in air-saturated waters than in deaerated waters. Galvanized steel generally exhibited higher tendency to pitting in the deaerated waters than in the aerated mine waters.

Jan 1, 1985

By C. W. Huggins

The objective of this Bureau of Mines research was to compare the size distribution of respirable quartz collected at coal mines with that of several reference standards used to quantify quartz in coal mine dust samples. Particle size measurements were made on 23 samples and 4 ref-erence standards using a scanning electron microscope in the backscatter electron mode of operation, interfaced with an image analysis system. The Mine Safety and Health Administration provided the 23 respirable coal mine dust samples, which were collected at surface and underground coal mines in 7 States. The accumulated particle size measurements in-dicate three of the reference standards, minus 5-um Min-U-Sil, minus 5-um Supersil, and NBS 1878, would be preferred over the fourth, Silver Bond B, for quantitative quartz determinations in coal mine dusts by X-ray diffraction and infrared spectrometry.

Jan 1, 1985

By S. L. Weber, V. Castranova, D. E. Banks, J. K. H. Ma, Y. Rojanasakul, J. Y. C. Ma, M. Bhat

"The mechanism of bleomycin-induced pulmonary fibrosis is not ye: clear. Recent studies have shown that alveolar macrophages (AM) can be stimulated by bleomycin in vitro releasing inflammatory cytokines, suggesting that the interaction of bleomycin with AM is an important step in the drug-induced fibrotic process. Bleomycin is known to bind DNA and generate oxygen radicals through complexation with Fe2+ and oxygen. To provide,more insight into the cellular oxidative property of bleomycin, v.s have developed a fluoromicroscopic method using 2',7'-dichlorofluorescin diacetate (DCFHDA) as an oxidative fluorescence probe to study the deomycin-induced intracellular oxidation in rat AM and the inhibition of the oxida¬tion by taurine, a compound known to inhibit the bleomycin-induced fibrosis. Bleomycin at 5 to 20 ug/ml has a moderate stimulatory effect (1.87- to 2.66-fold) on the secretion of superoxide anion. A high concentration of bleomycin (20 ug/ml), however, inhibits cell response to zymosan-induced secretion of superoxide anion. At 4 ug/ml, bleomycin has no effect on cell membrane integrity or morphology but results in a significant increase in intracellular oxidation. This oxidative process is Fe2-,-dependent and is accompanied by an increase in intracellular calcium (35 nM). Both the intracellular oxidation and calcium rise induced by internalized bleomycin are inhibited by pretreatment of cells with varying concentrations of taurine (25, 125, and 187.5 uM). The inhibitory effect on intracellular oxidation .vas found to be 36, 57, and 60%, respectively. These results demonstrate a stimulation-inhibition relationship between bleomycin and taurine on re cellular oxidation at a subcytotoxic dose of bleomycin, suggesting that the oxidative effect of the intracellular bleomycin-Fe2 complex is important in the initiation of the fibrotic process. — Environ Health Perspect 102 (Suppl10):91-96 (1994) IntroductionThe pulmonary system is most susceptible to oxygen radical-induced diseases due to its constant exposure to the highest oxygen tension, and the potential encounters with oxidant gases such as ozone, nitrogen oxides, and toxic doses of dust particles. The lung is also a well-perfused organ and thereby vulnerable to the effect of circulating xenobiotics such as paraquat, and, bleomycin, which is known to cause pulmonary injuries (1). Alveolar macrophages (AM), which act as a means of defense by phagocytizing inhaled dust particles and microorganisms while increasing production of reactive oxidative species, have been shown to play an important role in mechanisms leading to oxidative lung injury and fibrosis (2-4)."

Dec 1, 1995

By J. W. Town

Recrystallization studies on chrome-bearing spinel materials were made by the Bureau of Mines to determine the effects of certain fluxing agents and cooling rates on the chromium-to-iron ratio of recrystallized spinel. Statistically designed and evaluated tests showed that the ratio of chromium to iron in naturally occurring chrome spinel could be increased from 1.5 to 1 to over 7 to 1 and that the ratio of chromium to iron in the chrome-spinel in a stain-less steel slag could be raised to over 18 to 1. Silica, magnesia, and lime had significant positive effects, while alumina had a significant negative effect. Cooling rates of 200 C per hour in a programmed spiral globar electric furnace were satisfactory for growing crystals of recoverable size.

Jan 1, 1967

By L. H. Adami, E. G. King

The heats of formation of four sulfides --MnS ( alabandite ) , FeS ( hexagonal pyrrhotite ) , ZnS ( wurtzite ) , and CdS ( greenockite ) -- were determined by hydrochloric acid solution calorimetry . The heats of formation from the metals and rhombic sulfur at 298.15 ° K are , respectively , -51.01 ± 0.19 , -23.81 ± 0.24 , -45.86 ± 0.20 , and -35.70 ± 0.30 kcal /mole . The corresponding free energies of formation were calculated from the heats of formation and the pertinent entropy values .

Jan 1, 1964