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By G. H. Damon

Since 1963, Bureau of Mines Information Circular 8179 has served the mining industry as a fundamental safety guide in the field of blasting agents. In the intervening 14 years, many changes have occurred, and this report presents revised and new recommendations which recognize these changes. For example, AN-FO is now supplied mostly premixed, whereas in 1963 much of it was mixed by the blaster; aluminum metal (A1) and other fuels are now often added to AN-FO to increase strength, and flake aluminum powder is used as a sensitizer in water gels; and water gels or slurries that are now extensively used were just coming into practical use in 1963. To provide the widest possible margin of safety, some of the Bureau's recommendations are more stringent than existing regulations,

Jan 1, 1977

By J. Pasini

The Bureau of Mines has investigated novel methods of stimulating petroleum production from reservoirs in the Appalachian Region. An important consideration in applying stimulative production methods is the control and removal of solid precipitates from the boreholes of production wells. Where paraffin-base crude oils are produced, as in the Appalachian Region, the accumulation of paraffin may be particularly troublesome. Paraffin deposition is a major production problem that has confronted the petroleum industry for many years. Although considerable effort has been expended by industry and government, a suitable solution has not been found because of the individuality and complex nature of the deposits. Remedial methods used to prevent or remove paraffin fall generally into four classes: (1) Chemical, (2) physical, (3) operative, and (4) combination. Each class has many subclasses that apply to particular problems in different oil- producing areas. Recently, chemical inhibitors and the sonic pump have assisted operators in preventing and removing paraffin deposits. Because these methods are relatively new, their degree of application has not been completely evaluated.

Jan 1, 1963

By W. W. Agey

Under terms of cooperative agreements, the Federal Bureau of Mines Inter-mountain Experiment Station assisted the General Services Administration (GSA) in operating the manganese-ore purchasing depots at Deming. N. Mex., and Wenden, Ariz. A resident metallurgist stationed at the depots directed sampling of the ore lots for assaying, took samples for amenability testing, calculated acceptances for payments to shippers, and served as technical adviser to the depot manager. The Intermountain Experiment Station at Salt Lake City, Utah, tested the amenability of the ores to determine how much of the manganese could be recovered in concentrates assaying a minimum of 40 percent manganese (Mn) and containing a maximum of 16 percent iron (Fe), 15 percent silica (Si02) plus alumina (AI203), 0.3 percent phosphorus (P), and I percent copper (Cu) plus lead (Pb) plus zinc (Zn). All chemical analyses of the ores and test products were done at Salt Lake City. In all, 567 ore lots submitted to the Deming depot were tested by flotation to determine their amenability to concentration into specification-grade material; 421 lots were amenable, and 146 were unamenable, primarily because of high copper content or excessive silica or iron in the flotation concentrate. Chemical analyses totaling 42,700 were made on the ores submitted to the Deming depot and on the products of the amenability-test program.

Jan 1, 1959

By E. V. Cilento, K. A. DiGregorio, R. C. Lantz

"K. A. DIGREGORIO, E. v. CILENTO, AND R. c. LANTZ. Measurement of superoxide release from single pulmonary alueolar macrophages. Am. J . Physiol. 252 (Cell Physiol. 21 ): C677-C683, 1987.-An electrooptical method was developed to quantify superoxide (02) release from single rat pulmonary alveolar macrophages (PAM) during adherence to the bottom of a culture dish. This was done by measuring the reduction of nitro blue tetrazolium (NBT) to a diformazan precipitate at 550 nm from videorecorded images of individual cells. Temporal changes in cell optical density, which are proportional to the mass of diformazan produced, were calculated from videophotometric measurements of the change in light intensity over individual cells. Total diformazan produced increased 78 and 1263 with an increase in NBT from 0.5 to 1.0 and 2.0 mg/ml, respectively. Total diformazan produced and maximum rate of production among individual PAM varied two- to threefold providing strong evidence for heterogeneity in 02 production. Specific inhibition of 02 production by superoxide dismutase, iodoacetate, and chlorpromazine significantly reduced the total diformazan produced and maximum rate of diformazan production. Hydrogen peroxide was not involved in NBT reduction, since catalase alone did not significantly change diformazan production. This novel method to quantify 02 release from single PAM should be valuable in analyzing heterogeneity and single cell kinetics of O; production, in assessing the effects of exposure of cells to particulates on O; release, and in relating release to electrophysiological measurements.rat; nitro blue tetrazolium; macrophage heterogeneity; single cell kinetic PULMONARY ALVEOLAR MACROPHAGES (PAM) protect the lungs by phagocytizing foreign debris and bacteria (24). This process involves ingestion as well as destruction of foreign matter. Phagocytosis is usually accompanied by a respiratory burst that increases cellular oxygen consumption and glucose metabolism in the hexose monophosphate shunt (7), which leads to the release of highly reactive oxygen metabolites at the surface of the · plasma membrane (6, 27). These agents have been implicated in the killing of bacteria by phagocytes (22), but have also been shown to be toxic and have been linked to cancer, emphysema, arthritis, diabetes, and other diseases (17, 22, 30). Toxic effects may be a result of either an abnormally low production of metabolites, resulting in damage to lung tissue by respirable bacteria and dusts, or an abnormally high production, resulting in direct damage to lung tissue by metabolites themselves."

Jan 1, 1989

By E. J. Kloos, R. H. Schutz, B. I. Ferber

To Assist users in the selection of reliable and satisfactory respiratory protective devices, the Bureau of Mines has established five schedules of minimum performance requirements for the approval of respirators . The current revisions of these schedules include 13D for self-contained breathing apparatus, 14F for gas masks , 19B and the amendments to 19B for suppliedair respirators , 21B for dust , fume, and mist respirators , and 23B for chemical cartridge respirators . Copies of these schedules may be obtained from the Bureau of Mines, Publications Distribution Section, 4800 Forbes Avenue, Pittsburgh , Pa . , 15213 . Approval tests on respirators are performed only at the request of the manufacturer of the respirator and at his expense. If the device meets the approval requirements , a certificate of approval is granted on the complete respirator. This certificate states that as long as the respirator is manufactured as originally approved, or in accordance with any changes covered by an extension of the original approval, the manufacturer may advertise and sell his respirator as being approved by the Bureau of Mines. Many industries and regulatory agencies require that respirators approved by the Bureau of Mines be used where respiratory protection is needed. The Bureau of Mines, however, has no regulatory power over the use of the respirators that it approves. It acts as an impartial testing agency to insure the availability of suitable and safe respirators. At frequent intervals, the Bureau of Mines purchases approved respirators and replacement parts on the open market. These are examined for conformity to the approved status, and are checked to insure that the manufacturer's production facilities are maintaining a satisfactory quality control .

Jan 1, 1966

By Jack G. Croeni

The Bureau of Mines developed a method to extrude low-density tungsten powder billets into rods and sheet bar with high-energy-rate forming equipment. Billets were compacted and sintered in an atmosphere of hydrogen to obtain a density of approximately 60 percent. Extrusion was conducted at reduction ratios of 6.25 to 1 and 9 to 1 at 1,800° C to prod e high-density, sound material. Yield strengths obtained were higher than those of material produced by conventional powder-metallurgy techniques, but ductility was lower at high temperatures.

Jan 1, 1966

Comparative tests of four coals used industrially for coke production have been made by three laboratories of the Federal Bureau of Mines, each using its standard equipment and procedures for evaluating coal for coking. Two of the coals were blends used in the western and eastern sections of the United States, the third was a strongly coking coal widely used for producing coke in Alabama, and the fourth was a blend typical of those used for producing foundry coke in the Birmingham district. The coals used and the cokes produced from them covered a wide range of chemical and physical properties. The tests used at all three laboratories for determining the physical properties of the cokes were made according to ASTM (American Society for Testing Materials) methods. The excellent agreement found for the physical properties of the cokes indicated that, for the coals tested, the BM-AGA (Bureau of Mines-American Gas Association) 18-inch circular retort used at Pittsburgh, Pa" the 14-inch slot-type oven used at Denver, Colo., and the 17-inch slot-type oven used at Tuscaloosa, Ala., were substantially equivalent for evaluating coals for production of coke. Thus, added value is given to data obtained previously and independently at these three Bureau laboratories. INTRODUCTION Laboratory equipment to produce coke for evaluation has not been standardized by the industry. The results obtained with anyone design of equipment have been regarded as showing only the relative values of coal to produce coke of the requisite quality. Few systematic studies have been made to correlate results obtained in different types of equipment. Results of one, in which the Bureau of Mines participated, were published recently.2/ This

Jan 1, 1961

By H. B. Brunot

A complete list of permissible mine equipment , tested and approved by the Bureau of Mines previous to January 1 , 1947 , was published as Information Circular 7432.27 A list of permissible mine equipment tested and approved by the Bureau of Mines during the calendar year 1947 was published as Information Circular 7465.3/ The present list supplements Information Circular 7432 and includes all of the equipment approved during the calendar years 1947 , 1948 , and 1949. It therefore supersedes Information Circular 7465. The list also includes an appendix ( No. 2 ) giving the symbol that must be used by every cable manufacturer in marking trailing cables that have passed the test for flame resistance as stated in the amendment of October 21 , 1947 , to Schedule 2E . The items are numbered to indicate the consecutive order in which each type of machine or device was approved in its particular classification . Thus , Information Circular 7432 showed six air compressors on the active list ; five additional compressors , Nos . 7 to 11 , inclusive , in this category were approved during 1947 , 1948 , and 1949 . Several items that were listed in Information Circular 7432 have been repeated in this circular where it was necessary to show that approvals of such equipment were extended to cover an additional voltage rating or other changes . Equipment listed in these circulars is approved by the Bureau of Mines only when found , upon inspection and test , to comply with minimum standards of safety as outlined in schedules prepared on the basis of many years of experience in dealing with safety problems of the coal -mining industry . The use of such equipment in mines known to be gassy , as well as in those that may become so , is earnestly recommended in the interest of safety . This circular is published so that the industry may be kept informed as to the many types of machines , devices , and lamps that are available for reducing explosion and other hazards incident to coal mining . This circular and Information Circular 7432 give the complete list of permissible mine equipment that is available under the various classifications .

May 1, 1950

By J. E. Tiffany, N. A. Tolch

The Pittsburgh Experiment Station has made a survey of the properties and characteristics of the brands of fuse manufactured in the United States ; 25 samples were procured from 4 manufacturers representing the different brands offered on the market when the investigation was begun . It is believed that the field was completely covered except for special fuse made to order for a particular job .

Jun 1, 1934

By Howard P. Hamlin, John W. Sweeney

Shales , clays , and loess in Iowa were tested and evaluated to determine feasibility of producing lightweight aggregate by commercial rotary - kiln or sintering methods . Preliminary testing was conducted in a muffle furnace . Rotary - kiln tests were conducted in a 16 - inch by 14 - foot rotary kiln . Concrete cylinders and cubes were tested to determine qualities of the aggregate . Three samples made suitable lightweight aggregate by rotary - kiln methods and two by sintering .

Jan 1, 1964

By L. B. Pankratz

High-temperature heat-content values of pure lutetium sesquioxide and dysprosium sesquioxide were measured over the temperature range from 298° to 1,800° K. Similar data for cerium sesquioxide were calculated from measurements of a mixture of cerium sesquioxide and dioxide and known values for cerium dioxide. The results for lutetium sesquioxide are regular. Dysprosium sesquioxide has a minor thermal anomaly near 1,590° K, the extra heat absorption being 220 cal/mole, Hexagonal cerium sesquioxide undergoes a transformation around 1,050° K, which is only slowly reversible; consequently results were obtained for both the low- and high-temperature varieties. The original heat-content data are reported, and smooth values of heat content and the corresponding entropy increments are tabulated. Equations were derived to represent the heat-content values.

Jan 1, 1963

By G. S. Scott. R. L. Grant

Ammonium nitrate (NH4NO3), a white crystalline chemical compound composed of 35 percent nitrogen, 60 percent oxygen, and 5 percent hydrogen, has again attracted attention, due largely to the recent catastrophe on April 16 and 17, 1947, at Texas City, Tex. The fire and subsequent explosion on the steamship Ocean Liberty, outside the harbor of Brest, France, on July 28, 1947, has fur- ther increased the interest in the properties of ammonium nitrate. As a result of the Texas City disaster, several laboratories have undertaken research to determine more certainly what causes ammonium nitrate to detonate and under what circumstances. This is not the first time that ammonium nitrate has been involved in a disaster, and its properties reviewed from the standpoint of safety. The disaster at Oppau, Germany, in 1921, which involved an equimolec- ular mixture of ammonium nitrate and ammonium sulfate, prompted an intensive study in Europe and in America. In the United States the properties of am- monium nitrate are now of especial concern because very large quantites are being manufactured and shipped in interstate commerce and abroad. Many an- monium nitrate factories, which were built during the war, will manufacture increasing amounts of this compound for use as a fertilizer. It is the purpose of this report to present a brief summary and biblio- graphy of the published experimental facts about the properties and behavior of ammonium nitrate. The reader is referred to original publications for greater details of the investigative work, and for theoretical discussions. This report also includes a survey of ammonium nitrate fertilizer of the type involved in the Texas City explosions. In the past, authorities have not always agreed on the degree of hazard involved in the manufacture and handling of ammonium nitrate, as the following quotations from the literature indicate: Munroe (82) quoted the following from Turner's Chemistry (a book pub- lished in 1835): "When this salt is exposed to fire, it liquefies, emits aqueous vapor, dries and detonates." Berthelot (14) in his book, Explosives and Their Power, 1983, wrote: "Ammonium nitrate from the point of view of its volatility, and cn account of many considerations, may be regarded as a typical explosive substance."

Jun 1, 1948

By M. R. Geer

Three coals from the Wilkes on - Carbonado district of Pierce County , Washington , were subjected to washability analyses to estimate the amount and quality of washed coal obtainable . Because the coals were unusually difficult to clean , the washability examinations were supplemented by table tests , tests in dense - medium cleaning units , and flotation tests . None of the coals could be reduced to the desired 10 percent ash by tabling and the response to flotation by two of them was poor . Dense -medium treatment provided coal of the desired quality , but with the most difficult coal the recovery efficiency was lower than usual .

Jan 1, 1964

By Scott Turner

Within recent years , people have begun to realize the importance and significance of the mining and allied industries . The leading part the engineer plays in civilization is becoming recognized . However , accurate quantitative knowledge of the industrial importance of mining is still seldom possessed except by those close to this business . It is true that there are a few who go to the extreme and represent the whole progress of civilization as a reflection of man's gradual mastery of mineral utilization , but on the whole , the magnitude of the industry is underestimated . The uncertainties of mining , as evidenced by the variable results of prospecting on surface or underground , in an unknown new field or from the bottom levels of a mature mine , the ins and outs of tonnages and metal contents , the possibility of a widespread or even a sudden change between cost and realization-price , add to its picturesqueness and make mining attractive to some . To many , the fact that results are generally more uncertain and less predictable than in other industries lends added charm . The following pages may serve to call attention briefly to the importance of mining relative to other industries in the United States , in Canada , and in the world . Ordinarily , the annual primary mineral production of the United States amounts to about 5 billion dollars . The average for the last five years has been a little over 5 billion dollars . Last year , sadly enough , it was less than 34 billions . Just now , we are on the decline , and have been for the past two years . In Canada , the 5-year average was about 268 million dollars . Last year it was 227 million . Due in part to gold output ( in 1930 , for the first time , Canada's gold production exceeded that of the United States ) , the Canadian average is holding up better than ours . It has been estimated that the average world mineral production over the past five years has amounted to about 12 billion dollars , while in 1931 it was less than 8 billions . The mineral industries are as indispensable for the conduct of modern society as are those of agriculture , but , in the United States at least , they receive far less recognition from the Government . With us , agriculture is fostered by a great department that is maintained by enormous appropriations , while the mineral industries get but little financial support . In the United States , in the calendar year 1930 , the value of production by these two industries were as follows : to 1 . Agriculture ( inclusive of forestry ) 9.9 billion dollars ; mining 4.8 billions ; ratio 2 Direct appropriations by our Federal Government were 109 million dollars to agriculture and 2.8 million to mining , a ratio of 39 to 1. Obviously this is out of balance to the extent of 19 to 1 in favor of agriculture .

Jun 1, 1932

By L. Garner McDonald

The U.S. Bureau of Mines, under contract to the U.S. Department of Energy, investigated the erosive-wear properties of seven commercial alloys with potential applications as valves for coal-conversion plants. A dry particle, jet-erosion apparatus was used to determine the wear of seven materials: 316 and 440-C stainless steels, K-68, K-701, and K-801 cemented tungsten carbides, HC-250 white cast iron, and Haynes 6B. The alumina abrasive entrained in the nitrogen gas jet had particle sizes of 27 or 50 µm, the abrasive velocities were 55 to 170 m/s, and the particle impingement angles were 15° to 90°. The maximum specific wear for ductile materials was found to occur at impingement angles of 15° to 30°, and the minimum specific wear occurred at 60° to 90°. For the brittle materials, maximum specific wear occurred at impingement angles of 50° to 85° and minimum specific wear was at the lowest angles. As the velocity and erosive particle size increased, the specific wear increased. The specific wear was related to the velocity by the power function WocAVn, where n was 1.8 to 3.9 for ductile materials and 1.8 to 3.6 for brittle materials.

Jan 1, 2010

By J. L. Holman

The Bureau of Mines is conducting research to recover strategic and critical metals such as Ni, Co, and Cr from mixed contaminated super-alloy scrap. One approach being studied involves melt refining of superalloy scrap to produce anodes for electrolytic deposition of Ni-Co alloy. This melt refining of superalloy turnings is described based on melt-oxidation and oxidation-carburization experiments, using roasted superalloy grinding sludge to supply the 0 needed to oxidize Cr and other readily oxidized elements to the slag. Controlled melt-carburization subsequent to oxidation improved the metal phase recovery of Ni and Co to well over 90 pct and decreased electrolytic solubility of Cr, Mo, and W by carbide formation. Electrolytic refining experiments were conducted using a controlled-potential mode (preset cathode potential). Data show effects of Fe and Cr impurities, cation concentration, electrolyte pH, S04-Cl electrolyte ratio, temperature, cathode potential, and cation-selective membrane use on current efficiency, current density, and deposit composition. Disposition of Ni, Co, Cr, MO, W, and Fe is compared for melt-oxidized versus oxidized-plus-carburized anodes. Deposits containing >97 pct Ni + Co (major impurity Fe) have been routinely obtained from scrap anodes. Research is continuing to improve deposit quality in sustained deposition and to recover Cr and other metals from refining slags and anode sludges.

Jan 1, 1986

By R. A. Cattell

With the surrender of the Japanese Imperial Government as a climax to the capitulation of the German High Command , the main objective of the Petroleum and Natural Gas Division pivoted from war assignments to its main normal functions . One of these functions is to give wide public distribution to valuable technical facts which the Division has obtained through research on petroleum , natural gas , helium , and related subjects . During the war years many engineering data and scientific facts could be released only on a restricted basis as reports to war agencies and others immediately concerned . Moreover , many of the wartime reports contained masses of detailed data that were prepared under stress to meet emergency schedules . For peacetime publication and application , these data must be reviewed , correlated , and rearranged so as to present the essentials in proper form . To illustrate , a wartime report of 50 pages might be resolved into one curve in a composite graph for a peacetime publication . Another factor affecting the orientation of the work of the Division is the broader horizon of research revealed by its war activities . Fundamental research and careful engineering analyses are just as important in time of peace as in time of war; in fact , they should be more important to the forward view , because under peace conditions disrupting influences that distract from the orderly acquisition of knowledge are minimized . Therefore , the concerted effort has been not to " salvage " the results of the war activities , but to evaluate them on the basis of their relative importance in the future economy of the country . Where wartime investigations have pointed to peacetime accomplishments , the effort has been to give the corresponding type of work additional emphasis . This adjustment can not be made hurriedly , but many of the necessary preliminary steps on the new course have been taken ..

Jun 1, 1949

By E. B. Swanson

Atlantic seaboard refining and marketing companies , dependent largely upon other producing and refining areas for the crude and refined petroleum needed to meet the demand for petroleum products within the Atlantic Coast States , reported an increase in 1929 receipts of 2,542,000 barrels of crude petroleum and 13,479,000 barrels of gasoline over the quantities received during the preceding year . The relatively large expansion in gasoline receipts undoubtedly resulted from the unexpected increase in gasoline consumption which characterized the petroleum industry during 1929. Gasoline receipts from California increased 6,354,000 barrels and shipments from foreign countries were 5,381,000 barrels in excess of the 1928 figures , while receipts from Gulf Coast ports , the major source of outside supply, declined 811,000 barrels . Shipments of domestic crude oil by tanker from Gulf Coast ports during 1929 continued the average annual increase of approximately 7,000,000 barrels which has been recorded during the five years of this annual survey . These shipments have increased from 72,556,000 barrels during 1925 to 99,828,000 barrels during 1929. Shioments of Mid- Continent crude by pipe- line to Atlantic Coast refineries have , on the other hand , dropped from 11,903,000 barrels in 1925 to 1,409,000 barrels during 1929. Receipts of foreign crude oil declined 1,461,000 barrels from the preceding year . : Gasoline demand within the Atlantic Coast area reached a total of 123,345,000 barrels , an increase of 15.7 per cent over 1928. Gasoline production increased 4,157,000 barrels , while tanker receipts were nearly 11,000,000 barrels larger than in 1928. Indicated shioments from Appalachian refineries were somewhat larger than in the preceding year . Gasoline production showed an average of 33.5 per cent of the crude throughout , as compared with 31.5 per cent in 1928 and 32.7 per cent in 1927. Cracking operations accounted for 44.6 per cent of the gasoline produced , as compared with 40.6 per cent in 1928 and 35.3 per cent in 1927. Gas oil and fuel oil production averaged 52.8 per cent of the crude throughput , as compared with 55.1 per cent in 1928 and 49.5 per cent in 1927 , the decline reflecting the smaller quantities of foreign crude refined during the year .

Nov 1, 1930

By L. A. Haas

The feasibility of removing sulfur dioxide by carbon monoxide reduction in a fixed-bed catalytic reactor was investigated by the Bureau of Mines. The reduction rate of sulfur dioxide with carbon monoxide was significantly dependent upon the iron and alumina content of the mixed catalyst. Maximum catalytic activity was obtained with about 40 percent iron-alumina mixture with a nominal gas mixture of 10 percent carbon monoxide, 5 percent sulfur dioxide, and the balance nitrogen. The synergistic effect of this catalyst mixture was explained by a dual reaction site mechanism, with both iron and alumina augmenting their specific sites at their interparticle contacts. The catalytic activity also increased with decreasing catalyst pellet size. With O.7-mm pellets, the entire pellet appeared to be catalytically active in a 2-gram catalyst bed. The apparent activation energy of the reaction was 18.3 kcal per mole in the temperature range of 350° to 600° C. Carbonyl sulfide (COS) was produced by the interaction of carbon monoxide and sulfur. The amount decreased with decreasing CO concentration. The ratio of COS formed per SO2 removed reached a maximum at about 400° C. The reaction rate appeared to be independent of S02 concentration in the range of 0.2 to 16 percent. The rate, however, increased directly with the CO concentration in the range of 5 to 20 percent. The presence of CO2 (<15 percent) had no appreciable effect on the rate. However, not over 0.5 percent oxygen could be tolerated. This method appears feasible for removing S02 from waste gas if the oxygen is removed prior to the catalytic S02 reduction process.

Jan 1, 1971

By J. M. Singer

Quenching distances for flames of methane-coal dust mixtures were determined with air and oxygen-enriched air. Coals used were Pittsburgh, Sewell, and Pocahontas No.3. Quenching distances were greater for flames of hybrid mixtures of coal dust and methane than for methane flames of corresponding stoichiometry. From the data of quenching distances and methane-coal dust concentrations was calculated the quenching equivalence, which is the increase in coal dust concentration required to maintain a given quenching distance value as the methane concentration decreases. These equivalences could be useful in identifying hazardous methane-coal dust mixtures in mines.

Jan 1, 1966