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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 Charles W. Huggins

DEVELOPMENT of the electron microscope has permitted man to examine many small objects that could not be resolved by the light micro-scope. Diffraction, spherical aberration, and chromatic aberration are the main factors that limit resolution to about two-tenths micron with the light microscope. No matter how perfectly a light microscope is constructed and operated, it cannot possibly resolve points separated by less than two-tenths micron. Rapid development following World War II has produced many electron microscopes capable of 20 A resolution. Fibrous inorganic minerals are well suited for electron microscopic study. Many micrographs of chrysotile have been published, but electron microscopic study of the amphiboles has been somewhat neglected. New techniques in sample preparation have simplified the study of fibrous material. Ultrasonic energy has been very helpful in sample dispersion. This publication contains a representative group of electron micrographs of natural inorganic fibers that have industrial value. These fibers commonly are referred to as the asbestiform minerals. The Bureau hopes that the knowledge gained through electron microscopy and other scientific study of the natural inorganic crystalline fibers eventually will lead to the production of synthetic fibers that will satisfy the requirements of industry.

Jan 1, 1959

By Halagowder Devaraj, Mostafa Sheykhnazari, Veer P. Bhavanandan

"A sensitive colorimetric assay for detecting mucins and glycoproteins rich in 0-glycosidically linked saccharides is reported. The method combines the susceptibility of N-acetylgalactosamine terminating 0-glyco idically linked saccharides to P-elimination with the Morgan-Elson reaction for N-acetylhexosamines with free reducing ends. All mucin and mucin-type glycoproteins but none of the serum-type glycoproteins tested resulted in characteristic color production. All mucins tested gave linear responses in the range 5 to 200 ""g and the assay was also adapted to the microscale involving the use of 96-well microtiter plates. The microassay in which the volumes of samples and reagents are scaled down 2.5-fold was particularly useful in monitoring of mucins, in the presence of other glycoconjugates, in large numbers of samples obtained during fractionation procedures. Cesium chloride, cesium bromide, potassium thiocyanate, and various detergents do not interfere with the colorimetric determination. Guanidine hydrochloride, cesium triftuoroacetate, and B-mercap- . toethanol decreased color by 30 to 45%; however, the interference was not serious to prevent the use of the method for detection of mucins in their presence. The use of the method for the specific detection of mucin during fractionation by gel filtration and density gradient centrifugation of cystic fibrosis sputum samples is demonstrated. Mucins are an important class of biomacromolecules whose structure-function relationship is poorly understood (1,2). The investigations of mucins are hampered by difficulties in purifying these very large size molecules which appear to avidly bind other components of the mucus (3,4). One of the problems during purification is the specific detection of mucins. For example, during the various purification steps, the fractions containing mucins are typically detected by assaying for neutral sugars (hexoses) (5,6), for sialic acids (7), or for periodate oxidizable saccharide units (8). However, these methods are not entirely satisfactory because neutral sugars, sialic acids, and periodate-oxidizable saccharides are also components of other glycoconjugates. In addition, the neutral sugar and sialic acid measurements are also subject to interference from high levels of proteins and nucleic acids."

Jan 1, 1990

By G. W. Birge

Carbonizing properties of the principal coal beds of Butler County, Pa., are described in this report by the Bureau of Mines. Eight samples, representing the Upper Freeport, Lower Freeport, Upper Kittanning, Middle Kittanning, Lower Kittanning, Clarion, and Brookville beds, were carbonized at 900° C. by the Bureau of Mines-American Gas Association (BM-AGA) method. Butler County coals rank as high-volatile A bituminous and are generally characterized by high sulfur content compared with Appalachian coals used for industrial coking. If cleaned, the Brookville and one sample of Upper Freeport coal would be acceptable as the major component of metallurgical coking blends. The other Butler County coals tested would be unsuitable for this purpose because of either excessive sulfur or poor coking properties.

Jan 1, 1962

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 Benjamin W. Haynes

Cement kiln dust (CKD) produced in the contiguous United States and Hawaii was characterized as part of the Bureau of Mines' program in minerals environmental technology. The mineralogical and chemical composition was determined for 113 CKD samples from 102 plants that normally send CKD waste to landfill. Characterization included the determination of 28 elements, 7 anion species, carbon dioxide, noncarbonate carbon, and chemically bound water. Mercury was determined in 15 samples. Interelement correlation coefficients were determined for 23 elements, 5 anions, CO2, noncarbonate carbon, and chemically bound water. To assess the hazardous waste potential of CKD, the U.S. Environmental Protection Agency Extraction Procedure (EP) toxicity test was performed on all 113 CKD samples. All but one sample were in compliance with the test; the noncomplying sample slightly exceeded the EP toxicity test criterion for lead.

Jan 1, 1982

By G. R. Hopkins

[A new record in fuel efficiency at petroleum refineries was established in 1939, when a the average B.t.u. requirements per barrel of crude oil processed declined to a new low of 557,000 B.t.u. (see fig. 1). The average fuel requirement per barrel of crude oil refined has remained virtually stationary for the past 3 years. Thus in 1937 the average was 562,000 B.t.u., in is it rose to 567,000 B.t.u., and in 1939 it declined to 557,000 B.t.u. she largest gains in fuel economy cane a decade or so ago on the widespread introduction of heat exchanges and pipe stills. In recent years many successful innovations in heat saving have been adopted, but the combined effect of those is completely masked by the degree to which the capacity is utilized. Some heat requirements are relatively inelastic, so the average consumption per barrel of crude oil refined tends s to increase when the operating ratio (crude runs divided by capacity) declines and vice versa. In 1939 crude runs to stills increased 6 percent (from 1,165,015,000 barrels in 1938 to 1,237,840,000 in 1939) compared with a decline of about 2 percent in 1938. The operating ratio in 1939 was 82 percent compared it's 78 percent in 1938.]

Jan 1, 1941

By E. Morrice

The Bureau of Mines investigated methods for beneficiating platinum-palladium ores from the Stillwater Complex, Montana. Results of bench-scale and pilot-scale studies employing froth flotation to recover sulfide concentrates containing platinum-palladium values from a serpentinized ore are presented. Best results in the pilot mill were obtained with a sodium isobutyl xanthate-normal dodecyl mercaptan col-lector combination at a natural pH of 8.2. A rougher concentrate con-taining 1.7 oz/ton Pt and 4.7 oz/ton Pd was prepared. Recoveries of platinum and palladium were 96 pet and 86 pet, respectively. Batch cleaner flotation of rougher concentrates yielded concentrates contain-ing 3.7 oz/ton Pt and 9.8 oz/ton Pd.

Jan 1, 1984

By A. M. Gaudin

A study of the consumption of reagents used in flotation gives useful data as to the market which employment of the flotation process creates for the manufacturers of the necessary chemicals and oils, and furnishes a useful clue to the trends in flotation practice influencing the choice of reagents used and the' extent to which new reagents are displacing less suitable older reagents. In the present investigation an attempt has been made to cover both of these phases of the consumption of reagents in flotation. Unfortunately, however, the data collected in tie various districts have not been equally informative; some operators have reported very completely both the consumption of reagents and the metallurgical results obtained therewith, while others were apparently unable to supply these figures in sufficient detail to meet the requirements of this investigation. RESULTS OF INVESTIGATION Table 1 gives the tonnage of ore treated by flotation, as reported. This table shows that flotation has been most largely used in the concentration of copper ores, next in complex lead-zinc ores, followed by lead ores, zinc ores, miscellaneous ores, and copper-iron ores.

Jan 1, 1929

By Raja V. Ramani, Robert L. Frantz

"The U.S. Bureau of Mines (USBM) established on August 15, 1983, a Generic Mineral Technology Center (GTC) for Respirable Duet within the Mining and Mineral Resources Research Institutes (MRIs) at The Pennsylvania State University (PSU) and West Virginia University (WVU) in association with participating MRIs at Massachusetts Institute of Technology (MIT) and the University of Minnesota (UMN). The primary goal of the Center is to reduce the incidence and severity of respirable dust disease through researching and advancing the fundamental understanding of all aspects of respirable duet associated with mining and milling and the interaction of dust and lungs. Other Center activities include the training of engineers and scientists, graduate students and undergraduate students through their respective institutions, and the technology transfer to the industry. The Center also serves as the reference center for publications in the respirable dust area.Exposure to respirable contaminants in mine atmospheres has long posed a serious hazard to miners. The control of these hazards, some of which can have sudden and catastrophic effects and some others, slow and long enduring consequences, has been a major concern for labor, management and government alike. This concern has manifested itself in four primary mechanisms of control -- (1) regulatory control through minimum standard setting by the passage of mine health and safety laws, (2) engineering control through design and operation of mines according to the best recommended practices, (3) interaction of dust and lung control through periodic physical examinations, wearing personal protection devices, etc., and (4) legal and social control through workmen's compensation laws for occupation related health deterioration.The stated objective of the Federal Mine Safety and Health laws is to ""... permit each miner the opportunity to work underground during the period of his entire adult working life with-out incurring any disability from pneumoconiosis or any other occupation-related disease ....""Significant progress has been made in lowering the dust levels in mines since the inception of the Bureau's respirable dust research program. It is generally agreed that mines are less dusty today than they were a decade ago. However, the most serious hazard for workers in the mining and minerals processing industries is still the exposure to respirable dust, and solutions to the problem of respirable dust disease remain to be found."

Aug 31, 1989

By John A. Breslin

Size distributions and concentrations of particulates emitted from diesel engine exhausts were measured with cascade impactors. Samples were taken from the exhaust of two types of engines using three types of fuel and operating under five different engine speed and load conditions. The measured mass median diameters of the diesel particulates were typically about 0.3 um. There was no significant difference in mass median diameter between engines or fuels and only a slight dependence on operating mode. Concentration measurements ranged from 14.2 to 250.9 mg/cu m, and calculated mass outputs, from 64 to 10,000 mg/min. Significant differences in mass output were found between engines, fuels, and especially between different operating modes. The quantity of clean dilution air that would be required to reduce the particulate mass concentration below the 2.0 mg/cu m respirable dust standard for coal mines was greater than the dilution air required to meet the standards for noxious gases for both engines tested.

Jan 1, 1976

By D. W. Bridges, R. O. Dannenberg, Laird Crocker

Preliminary solvent extraction studies , reported by the Bureau of Mines (5) , have been continued and expanded to improve on the previous estimate of process requirements . The solvent extraction portion of the process was examined at a scale large enough to enable meaningful extrapolation of the results to geometrically similar equipment of plant size . About 82 pct of the beryllium was recovered from approximately 0.5 pct beryllium oxide (Be0) Spor Mountain , Utah , ore by a process involving ( 1 ) sulfuric acid leaching , ( 2 ) counter current decantation (CCD ) washing , (3 ) iron ( III) reduction by sodium hydrosulfide ( NaHS ) , ( 4 ) beryllium solvent extraction by di - 2- ethylhexyl phosphoric acid ( EHPA) , ( 5 ) caustic stripping of beryllium- bearing EHPA, (6 ) hydrolysis of sodium beryllate - caustic strip liquor , and (7 ) calcination of beryllium hydroxide (Be ( OH ) 2 ) formed in step (6 ) . The resulting beryllia assayed 98 to 99 pct Be0 and was suitable for most nonnuclear uses . Best overall results were obtained by using pH 2 , 1.6 grams of BeO per liter of leach liquor as feed and 0.25 N EHPA in kerosine containing 2 wt vol pct (grams per 100 ml of solution ) isodecanol ( IDA ) as solvent . Analysis of the data indicated that a commercial plant would achieve 95- pct overall extraction operating at 45 ° C with 20 hp per 1,000 gal of dispersion in each of seven mixer- settlers , having 290 gal per ton of ore hourly mixer capacity and 90 gal per ton of ore hourly settler capacity . At least 79 lb H2SO4 , 13 lb sodium hydroxide (NaOH ) , 3 lb NaHS , 0.25 lb kerosine , 0.07 lb polyacrylic flocculant , 0.03 lb EHPA , and 0.007 lb IDA would be required in H2SO4 leaching and subsequent processing to recover 1 lb BeO .

Jan 1, 1964

By Paris V. Brough

This paper, which describes the practice of milling custom ore, in addition to that produced under company and lease operations in the Tom Reed mines, is one of a series 'being prepared by the Bureau of Mines. ACKNOWLEDGMENT Acknowledgment is made to W. B. Phelps, managing director, and Jack Zwinge, superintendent, far permission to publish, a-ad to G. E. Jarpe, the present mill superintendent, for his assistance in preparing the paper. LOCATION The mill is in Oatman, adjacent to the Benjamin Harrison shaft of the Tom Reed Gold Mines Co., in the foothills on the western slope of the Black Mountains, western Mohave County. The railroad shipping point is Kingman, Ariz., 25 miles northeast of Oatman. Paved highway U. S. 66 passes by the mill. The altitude is approximately 2,700 feet.

Jan 1, 1937

By F. D. DeVaney

[In the course of the investigation by the U. S. Bureau of Mines and the Missouri School of Mines and Metallurgy at the Mississippi Valley experiment Station at Rolla, Mo., on the beneficiation of the low-grade manganese ores of the country, some samples from the Cuyuna District, Minn., have been examined. The work was done under the direction of W. H. Coghill, supervising engineer of the Mississippi Valley Experiment Station. Josoph and Kinney5 in venting about the relative importance of Minnesota deposits of low-grade ore compared to the total reserves say:]

Jan 1, 1930

By Helen E. Edwards

The Bureau of Mines is engaged in a systematic evaluation of the thermodynamic properties of combustion gases. These studies are designed to provide basic thermodynamic information of high accuracy facilitating the theoretical study of flame and combustion phenomena. This report is the third of a series3/ presenting results of the study for particular fuel-oxidant systems. The equilibrium composition of the products of combustion and the adiabatic flame temperatures of specified oxyacetylene systems have been computed.

Jan 1, 1953

By G. R. Hopkins

[A new record in fuel efficiency at petroleum refineries was established in 1939, when a the average e B.t.u. requirements per barrel of crude oil processed declined to a new low of 557,000 B.t.u. (see fig, 1).]

Jan 1, 1941

By J. B. Zink, M. J. Peterson

A semiquantitative spectrochemical method was developed and applied to the analysis of ash of U.S. coals . A low- temperature ashing procedure was used to minimize the loss of volatile elements . The analytical procedure provides for the estimation of 68 elements including major , minor , and trace constituents . Standards for the trace elements were prepared in a synthetic base mixture that approximates the average composition of U.S. coal ashes . Excitation was achieved with a d- c arc , spectra were recorded photographically , and interpretation was made by visual comparison of spectra of unknowns with spectra of graded standards series . Thirty- six trace elements were found in the analysis of 900 samples . Details of the procedure are presented , including sample and standards preparation , excitation and exposure conditions , spectral lines used , and approximate limits of detectability .

Jan 1, 1964

By Jerry Olson

The Bureau of Mines (Bureau) conducted a mineral resource investigation of the French Creek-Patrick Butte study area, in west central Idaho during 1989. No mineral resources or significant occurrences were identified. Other than small scale placer gold, no mineral production is known or recorded. At least 100 lode and 150 placer claims have been located in the study area. Most of the area was examined by ground or areal surveys, and 110 lode and 60 placer samples were taken. Four lode prospects were examined in detail, and all placer claim locations were sampled.

Jan 1, 1991

By Robert H. Ridgway

Scrap iron and steel attracted attention during 1937 because of the unprecedented exports and the concomitant agitation in some quarters to prohibit the exportation of this essential raw material except on license by the President. This report does not attempt to analyze the statistics given in the light of the controversy over the limitation of scrap exports, but it is believed that students of this problem will find many essential basic data in the various tables presented herein. This paper presents the results of the third in the series of annual canvasses on the consumption of ferrous scrap and pig iron in the United States. The study was inaugurated in 1935 by the Bureau of Mines in response to requests from trade organizations and others for detailed

Jan 1, 1938

By John W. Kopp

Stemming is used in blasting operations to help contain explosive gases as long as possible. Stemming can reduce airblast, improve fragmentation, and reduce the chances of hot explosive gases igniting methane and dust explosions in underground mines. Stemming is required in underground coal mines but is generally not used in underground metal and nonmetal mines. Some underground metal and nonmetal mines are classified as gassy and can require special blasting procedures such as the use of stemming to minsure the safety of miners. The types and amounts of stemming material that are desirable in underground metal and nonmetal mine blasting to ensure good or improved fragmentation while containing the hot gases are largely unknown. This Bureau of Mines research examined the effectiveness of differing lengths of stemming by measuring stemming ejection times as related to burden movement. With properly stemmed blasts, stemming is contained until some burden movement has occurred. Test blasts at two surface limestone quarries were evaluated using high-speed photography. For the conditions of these tests, a stemming length of at least 26 charge diameters was found to prevent premature stemming ejection. In tests with stemming lengths of 16 charge diameters, the stemming was effective but there was early venting of hot gases through fractures in the rock. Further testing with other rock types, hole diameters, explosive types, and stemming materials as they affect incendivity is recommended.

Jan 1, 1987