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By Paul Zinner

An exhaustive program of geologic studies and mapping has been conducted by the Geological Survey in the Iron River district of Michigan since May 1943. Means of contributing to the success of these studies were sought by the Bureau of Mines, and eventually a program involving geophysical studies and core-drilling was undertaken in the area. All of the work was done either to develop data that would contribute directly to geologic studies or to investigate geophysical methods that might be used as a primary means for the discovery of minable iron ore.

Jan 1, 1949

By Jimmie C. Rosenbruch

The Federal Bureau of Mines evaluated the prospects for using geothermal energy to generate electricity for mines in remote areas. Given the development of a geothermal resource for this purpose, the subsidiary uses of space heating and agriculture were then examined to see if other industries might be viable given a cheap source of heat energy. Sites investigated were located in three areas of Alaska: Kobuk in the northwest, Unalaska in the southwest, and Stikine River in the southeast. Each site was relatively close to mineral deposits whose prospects for development would be enhanced with cheap power.

Jan 1, 1975

By Roy H. Poston

This paper sets forth the mode of ore occurrence, characteristics of ore and country rocks, methods of exploration, development, and. ore extraction, and the costs of underground operation at No. 8 mine of the St. Louis Smelting and Refining Works of the National Lead Co. located near the southern extremity of the Southeast Missouri lead district. The author acknowledges the assistance of E. T. Campbell, geologist, in the preparation of the paragraphs on the geology of the ores. HISTORY The first record of mining in St. Francois County, Mo., concerns more or less shallow semisurface "diggings" which were worked about the year 174-2. In 1864, however, the discovery of the disseminated deposits, the present source of lead, was made on property near the town of Bone Terre. Winslow has estimated the lead-ore production in this county prior to 1869 to be 59,526 tons.3

Jan 1, 1929

By R. F. Zaffarano

Reservoir oil in the Greater Aneth area, Utah, part of the Paradox basin, was studied to detect variation in oil characteristics within the reservoir and to determine its relation to age of accumulation and fluid equilibrium. At least three subsurface oil samples were obtained from each of the four largest of five field divisions comprising a producing area of 45,000 acres. Height of the oil column in the Pennsylvanian Desert Creek zone is about 230 ft. In general, the oil characteristics were found to be uniform across the area, and averages were developed for use in engineering applications. Average saturation pressure was 1,780 psia; the oil was undersaturated at the initial reservoir pressure, 2,200 psia. Variation in saturation pressure shows a lack of complete fluid equilibrium and continuing diffusion of solution gas from the main body of the reservoir to two extensions linked by narrow arms. By assuming early accumulation, the time involved in this diffusion process was calculated to be about the same as the age of the reservoir formation. Cause of the concentration of gas in the main body is attributed to differential entrapment during accumulation of oil and gas from an exterior source.

Jan 1, 1963

By John C. Holtz

"INTRODUCTION Information on the gaseous products from the detonation of explosives has been obtained in two ways. In the first, the atmosphere in mines is analyzed after blasting, and in the second, the gases found after detonating an explosive in a testing apparatus are analyzed. The Bureau of Mines, in a cooperative research 3/ that compared data obtained in the field with those obtained in the testing station, showed that the results were not in entire agreement. The production of carbon monoxide was found to be governed chiefly by the oxygen balance of the explosive, but the production of oxides of nitrogen did not change in so simple a manner. Because of the increasing interest in correlations between the composition of the explosive and the production of toxic gases, it seemed desirable to continue the investigation.PURPOSE OF INVESTIGATIONAs field tests are both time consuming and expensive and as field results are affected by factors that are not always under control of or clearly evaluated by the operator, the purpose of this investigation is to develop a testing-station procedure that will reproduce the gaseous products quantitatively under known conditions analogous to those that may be expected in the field. In addition, the factors affecting the formation of toxic gases, particularly oxides of nitrogen, will be studied,"

Apr 1, 1940

By L. A. Stinnett

An investigation of hazardous surface openings of abandoned and inactive underground mines in the Black Hills area of South Dakota has revealed: (1) tracing legal ownership of mineral claims via county courthouses is confusing, complex, and oftentimes misleading, (2 ) in general, the selected mine openings in this investigation are to be considered relatively high in risks and hazard potential which poses a threat to the general public, (3) mine closure procedures and designs can generally be categorically implemented depending on the overall situation of the particular mine opening with subsequent unit costs' estimates, (4) few preventive state or federal legal measures exist to date concerning mine closures, and (5) liability damages relating to mine opening accidents usually involve expensive and complex common law cases.

Jan 1, 1979

By R. G. Sandberg

The Bureau of Mines investigated a hydrometallurgical procedure to recover gold, silver, and byproduct lead from a complex lead-zinc sulfide ore. A ferric chloride (FeCI3) preleach, at 40° C in 6 h, extracted about 50 pct of the zinc and formed insoluble silver and lead chlorides. Subsequent acid thiourea leaching, for 1 to 3 h at 40° C, extracted about 85 pct of the gold and silver. Lead chloride was solubilized from the remaining residue with NaCI brine solution at 55° C in 1 h. Lead metal was recovered from the brine solution in an electrolytic cell with an anion perms elective membrane at a current efficiency of 95 pct and current density of 100 A/m2. Spent FeCl3 leach solution was reoxidized in the anode compartment at a current efficiency between 75 and 95 pct.

Jan 1, 1986

The strike of the Canadian asbestos miners entered its seventh month with increasing signs of early termination. Both unions are in the midst of heavy negotiations with management, and an optimistic industry source predicted that work would resume by October 1. Recession recovery in some segments of the asbestos manufacturing industry is being impeded by lack of fibers, CADMIUM - On September 9, St. Joe Minerals Corp. reduced the price of cadmium metal to $2.75 per pound. The producer price bad been uniformly quoted at $3.00 per pound since June 26, 1975. Subsequently, Amax, Inc. and National Zinc Co. reduced their prices to $2.50 per pound. By mid-September all five U.S. cadmium producers were marketing the metal at $2.50 per pound.

Jan 1, 1975

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 Gerald W. Elger

This report compares the quality of zirconium metal prepared by batch reduction of zirconium tetrachloride by (1) sodium, (2) magnesium, and (3) mixtures of sodium and magnesium. Criteria for quality are based on chemical analyses and hardness testing of zirconium arc-melted from sponge. The best quality zirconium with respect to low oxygen content and hardness numbers was prepared by reaction of zirconium tetrachloride with a mixture of sodium and magnesium. It was found that this reaction could be successfully carried out by two methods: (1) addition of sodium and magnesium before the initial reaction and (2) periodic injection of sodium during reaction of zirconium tetrachloride with magnesium. The largest quantity of metal was found to be recovered from experiments in which a mixture of sodium and magnesium was used. Magnesium appeared to be a better reductant than sodium because magnesium-reduced zirconium contained less oxygen and exhibited lower hardness numbers than sodium-reduced metal.

Jan 1, 1962

By James S. Grichar

Interest in mergers in the nonfuel mineral industry developed when 5 were listed among the 50 highest valued mergers in the United States in 1981. This report presents a Bureau of Mines study of trends in merger activity from 1960 to 1979 and explores motives for mergers in the nonfuel mining and mineral industry. The objective was to determine precedent for or a trend toward the 1981 acceleration in merger activity and to examine certain financial motives for non fuel mineral mergers. Data indicate that the relative value of non fuel mineral mergers has grown since 1972 although the number of mergers has remained proportionate to historical trends for all mergers. Since 1974, the assets acquired in "large," nonfuel mineral firm mergers, those of $10 million or more, have comprised at least 93 pct of assets acquired. More nonfuel mineral firm mergers involved mineral companies as the acquiring firm than vice versa but mining and minerals firms acquired were of higher value than nonmining firms. A major motivation for mergers involving large mineral firms was the acquisition of assets at less than replacement costs. Univariate statistical testing, a methodology chosen for its applicability to the data, confirms this hypothesis while rejecting other financial motives. The remainder of the work is devoted to a discussion of suggested areas for future study.

Jan 1, 1984

By E. C. Lane

[The motor gasoline that s being marketed in the United States this summer slightly more volatile then that sold a year ago. This increase in volatility is shown by a general lowering ref the average distillation rang, of about 2°F. During the post 10 years the Bureau of Mines has made semiannual surveys of the gasoline marketed in the United States, the survey just completed being the twentieth in the series. The 12 cities in which samples were collected have beer chosen as representative of the more important marketing territories, as it is obviously impracticable to obtain a sample of every gasoline sold in the entire country.]

Jan 1, 1929

By P. R. Miles, J. K. H. Ma, J. Y. C. Ma, L. Bowman

"The bisbenzylisoquinoline alkaloids are compounds which can be isolated from plants and which exhibit a broad range of pharmacological activities. Perhaps the best known alkaloid of this group is tetrandrine (TT), a compound isolated from the root of a traditional Chinese medicinal herb, Stephania tetrandra. It has been tested for its effects on the cardiovascular system, tumors, and the lungs. For example, tetrandrine has been shown to act as a calcium entry blocker in cardiac sarcolemmal vesicles (King et a/., 1988) and has been used in China as a treatment for angina and hypertension. Its possible effects as a tumor-inhibitory substance have also been investigated (Kupchan and Atland, 1973). In addition, there are several lines of evidence to suggest that it is a possible therapeutic agent for the treatment of silicosis. Yu et a/. (1983) have shown that TT inhibits the development of experimental silicosis in rats when it is administered orally after intratracheal instillation of quartz. Other studies have shown that the alkaloid inhibits the synthesis of collagen by fibroblasts and the formation of silicotic nodules in rats exposed to silica (Huang et al., 1981; Liu et al., 1983). In fact, tetrandrine has been used clinically in China as an antifibrotic agent and has been shown to improve both the appearance of chest radiographs and the measurements of diffusing capacity in patients with silicosis (Li et al., 1981).Since tetrandrine may have a potential use as a therapeutic agent for fibrotic lung diseases, its effects on various pulmonary cells and tissues should be studied. Alveolar type II cells are located in the alveolar regions of the lungs and are important because they are responsible for the synthesis and secretion of pulmonary surfactant (Dobbs et al., 1982; King, 1984), regeneration of the alveolar epithelium after lung injury (Kauffman et al., 1974), and metabolism of foreign compounds (Bend et al., 1985). Furthermore, in silicosis, for which TT has been suggested as a treatment, there are increased amounts of pulmonary surfactant produced (Dethloff et al., 1986a,b) as a result of increased rates of surfactant synthesis by type II cells (Dethloff et a/., 1989; Miller et al., 1988). Because type II cells play a critical role in maintaining normal lung function and because type II cells are affected in silicosis, for which 'TT has been used as a treatment, we studied the effects of tetrandrine on energy metabolism in these cells in vitro. Energy metabolism was chosen because it is a basic cellular function which is neces-sary for other cellular processes to occur. Since type II cells depend on mitochondrial metabolism for energy production (Fisher et al., 1980), we examined the effects of tetrandrine on cellular and mitochondrial ATP production and oxygen consumption. Additional experiments were performed in an effort to determine if intracellular calcium levels may be involved in the TT-induced effects. A preliminary report of those results has appeared previously (Ma et al., 1991)."

Nov 1, 1995

By John S. Berber

To improve the economics of low-temperature carbonization of coal, the Bureau of Mines is conducting research on the upgrading of the product tar to marketable chemicals. This report describes experiments on the catalytic hydrodealkylation, followed by catalytic vapor-phase oxidation of the dealkylate to phthalic and maleic anhydrides, of mixed residues from the urea adduction of lignite-neutral oil fraction and on the catalytic thermal dealkylation of high-boiling tar acids. The hydrodealkylation experiments were conducted at pressures from 1,000 to 1,750 psig and at temperatures from 600° to 1,000° F. The oxidation was, in all cases, at atmospheric pressure and 9500 F. Maximum yield of maleic anhydride, based on the liquid feed to the hydrodealky1ation unit, was 12.2 percent at 750° F and 1,500 psig; that of phthalic anhydirde was 6.9 percent at 650° F and 1,500 psig. Maximum yield of combined anhydrides was 18.8 percent at 650° F and 1,500 psig. The non-dealkylated feed material, upon oxidation, yielded 8.9 percent and 3.8 percent maleic anhydride and phthalic anhydride, respectively.

Jan 1, 1967

By D. A. Reynolds, C. R. Holmes

The Bureau of Mines - American Gas Association ( EM - AGA) carbonization test has been used to determine the carbonizing properties of 66 American coals and a larger number of coal blends . A summary of the results obtained for the first 30 coals , including 6 blends , has been published ,4/ and results for individual coals have been reported as the investigations were completed . A bibliography of all publications pertaining to this work has been issued recently . Many of the coals were carbonized at 800 ° and 900° C. in two sizes of retorts ( 13- and 18 - inch diameters ) ; and , because the quality of coke is affected by changing the size of the retort , this report has been prepared to show the average physical properties of coke from the two sizes . This report also purposes to extend the correlation of the physical properties of coke with the rank of coal made by Fieldner and Davis in their summary of the EM-AGA tests on the first 30 coals .

Jun 1, 1942

By Joseph A. Sutton, John D. Corrick

The chemistry involved in the microbial dissolution of iron and copper from such sulfide minerals as pyrite, chalcopyrite, chalcocite, cove11ite, and bornite is described. The chemical criteria used to evaluate the activity of microorganisms on these minerals were changes in pH, ferric iron produced, and oxygen consumption. In a series of experiments in which a ferrous sulfate nutrient solution was percolated over small portions of the above-mentioned copper sulfide minerals for 56 days, the iron-oxidizing bacteria Ferrobaci11us ferrooxidans and Thiobaci11us ferrooxidans were capable of bringing about the dissolution of 23.7 percent of the copper from chalcocite, 56.3 percent of the copper from cove11ite, and 29.8 percent of the copper from bornite by the microbial production of ferric sulfate which reacted with these minerals. Laboratory tests have demonstrated that pure strains of the iron-oxidizing bacteria act as catalysts to the ferrous iron being oxidized by the Oxygen of a system containing pyrite and chalcopyrite. In a series of experiments during which nutrient solution was percolated over pyrite for 70 days, the ferric iron produced by the iron-oxidizing bacteria was 112 to 120 times greater than that produced atmospherically.

Jan 1, 1964

By F. G. Schwartz

This circular presents the results of a survey of research on jet fuel thermal stability jointly sponsored by the National Petroleum Refiners Association (NPRA), Tulsa, Okla., and the Bureau of Mines. The development of supersonic planes has led to many problems that did not exist in the operation of subsonic aircraft. One of the most important of these is rapid deterioration of the fuel at the high temperatures to which it is subjected. At higher speeds, aerodynamic heating of the airframe imposes severe thermal problems, and conventional techniques of rejecting the heat to the atmosphere become impractical. The fuel is the only material present in sufficient bulk to be used as a heat sink. Thus, the fuel is subjected to aerodynamic heating and also is used to dissipate heat from lubricating oil, hydraulic fluid, electronic equipment, wheel wells, and cabin air. Consequently, the fuels may have to withstand both moderate temperatures for sustained periods in the fuel tanks and higher temperatures for brief periods during transfer from the tanks to the combustion chamber. Because of high temperatures, insoluble residue or gum may form in the fuel and contribute to heat exchanger fouling and to clogging of the fuel manifolds, nozzles, control systems, and other components of the fuel system.

Jan 1, 1962

By H. L. Gibbs

A portable radon monitoring instrument capable of making on-the-spot measurements of the radon gas content of uranium mine atmospheres was designed and constructed. The monitor was tested in the laboratory and in operating uranium mines. Good correlation was obtained between the monitor readings and radon measurements made on mine atmosphere samples taken in radon bottles.

Jan 1, 1973

By R. B. Prater

The Bureau of Mines conducted research to separate the F from byproduct Zn concentrates obtained from fluorspar (CaF2) production, as part of the Bureau's effort to devise efficient, environmentally acceptable technology for recovering Zn from resources considered undesirable by Zn producers. Sulfuric acid (H2SO4) was found to be effective in F removal, while ammonium carbonate [(NH4)2C031 was not. The most important variables for reducing the necessary residence time were found to be temperature and agitation. Optimum leaching conditions were 75° C and 500 r/min for 2 h at 40 pct solids with 0.2 g acid per gram of concentrate, which resulted in a 98.3-pct F extraction. Zinc losses during F removal were in the range of 2 to 3.3 pct. Other elements such as Fe, Cd, Ca, and Cu were also partially dissolved. About 93 pct of the F was removed from the leach solution by neutralization and precipitation with calcium hydroxide [Ca(OH)2]. Additional treatment might be necessary to limit the buildup of soluble elements in the recycled leach solution.

Jan 1, 1985

By V. E. Edlund

This report presents the results obtained in a study of the technical feasibility of recovering a usable pig iron by pyrometallurgical treatment of typical copper reverberatory slags . The iron in the slag was readily reduced with carbon , but the copper and sulfur content of the metal was best controlled by a three - stage procedure comprising ( 1 ) melting the slag with pyrite to remove copper as a low- grade matte , ( 2 ) smelting the partly decopperized slag with fluxes and carbon to reduce the iron , and ( 3 ) refining the impure iron alloy from step 2 with a flush slag to remove sulfur and residual copper . Laboratory - scale tests demonstrated that washing with 8 wt pct of pyrite lowered the copper content of a typical reverberatory slag from 0.58 to 0.12 Subsequent smelting of a mixture composed of 70 pct decopperized slag , 25 pct lime , and 5 pct coke reduced 84 pct of the iron to metal containing 2.27 pct sulfur . This metal then was successfully desulfurized by treatment with a basic flush slag to produce a finished metal that contained , in percent , 93.5 Fe , 0.02 S , 0.26 Cu , and 4.9 C. Overall recovery of iron under the conditions of trial was about 80 pct . This could be increased if higher tolerances for copper could be accepted . Commercial processing would be accomplished in three furnaces with molten materials passing from one to another . Currently produced smelter slag could be treated fairly inexpensively , because the molten product would require only a little additional heat to produce an iron byproduct that undoubtedly would be attractive to local foundries .

Jan 1, 1964