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By K. C. Dean

During the investigation of the occurrence of manganese deposits in western United States, the Bureau of Mines collected 2-ton samples from three oxide manganese ores in the Columbia and Elberta Mining Districts, Tooelo and Juab Counties, Utah. To determine the amenability of these ores to standard ore-dressing methods: of concentration, extensive laboratory tests were made. The Wildcat property, one of those sampled, is 7 miles east of Fairfield, Tooele County, Utah. The ore is described as a replacement deposit and occurs along fracture and bedding planes of shale and limestone. Experimental work was done on a sample taken from a stockpile at the mouth of the shaft. The Wildcat manganese ore is intermediate in grade (25.7 percent manganese) and contains clay as the principal gangue constituent. A high-grade product was obtained with high recovery of Manganese by simple washing.

Jan 1, 1949

By Seth C. Schaefer

The Bureau of Mines studied thermodynamic properties of Al-Ni alloys con¬taining 0.54 to 30.04 atomic percent nickel with the aid of the high-temperature galvanic cell Al(1) // Al+3 (AlCl3 in NaCI.KC1) // Al-Ni alloy (1 or s). Activities of aluminum and nickel (compared with pure liquid metals as the standard state) show pronounced negative deviation from Raoult's law at 1,273 K. The properties [?G, ?Gxs, ?G ideal, ?GA1, AGxs1, ?Gni , and ?GNixs] have been derived from the experimental data and are summarized in tables and illustrations. At 1,127 K, the thermodynamic stability for the invariant three-phase equilibrium consisting of a saturated liquid, A13Ni, and A13Ni2 has been uniquely defined by an activity for aluminum of 0.751. A free energy of formation at 1,127 K of -7,940 cal/g-atom was derived for the compound A13Ni.

Jan 1, 1975

By Steven J. Page

Accurate measurement of workplace respirable dust concentration is an essential step in eliminating lung disease in any occupational setting. In the United States (U.S.) coal mining industry, this measurement process has relied upon a personal sampler that includes a 10 mm Dorr-Oliver (DO) nylon cyclone operated at a flow rate of 2.0 L min-1 to collect a respirable dust sample. Dust concentrations measured with this sampler are multiplied by 1.38, which was empirically derived, to convert them to measurements approximating the United Kingdom British Medical Research Council (BMRC) definition of respirable dust upon which the health effects of coal mine dust are based. The International Organization for Standardization (ISO) subsequently refined the respirable dust definition and the U.S. National Institute for Occupational Safety and Health (NIOSH) 1995 Criteria for a Recommended Standard presented a conversion multiplier of 0.857 to apply to the 2.0 L min-' DO (in addition to thel.38 multiplier) to obtain equivalent ISO concentrations, as approximated by the 1.7 L min-1 DO. However, the conversion multiplier 0.857 was derived indirectly from a limited size distribution data set rather than a direct comparison of the DO samplers. The present analysis focuses on providing a more accurate conversion multiplier derived from direct comparisons of the 2.0 L min-1 (with 1.38 BMRC equivalency multiplier) and 1.7 L min-1 DO cyclones. A weighted linear regression analysis of this database suggests that a more accurate estimate of the conversion multiplier is 0.815.

Jan 1, 2009

By Wallace W. Roepke

The Bureau of Mines has a well-established health and safety research effort directed to fundamental studies of the mine cutting system. This report describes the ignition danger of using cutting bits with flat wear area on still-intact carbide inserts.

Jan 1, 1983

By John A. Davis, John Gross

Six tests were made by the Alaska Station of the Bureau of Mines on a sample of black sand delivered to the station by Messrs. James, Eagan & Griffen from Fairbanks Creek, Fairbanks mining district, Territory of Alaska, to devise a method of recovering the gold content. More than 90 per cent of this black sand consisted of magnetite and garnet which can be separated magnetically. The Station has no equipment for magnetic separation other than an electromagnet similar to the one used by Day and Richards, (Day, D.T., and Richards, R.H., Investigations of Black Sands from Placer Mines, U. S. Geol. Survey, Bull. 285, 1906, pp. 150-163), which can only be used satisfactorily on small samples. To treat the entire lot of black sand with this machine would have been impracticable. Therefore only a small part of the sand was so treated, the rest being divided into five lots in order to obtain comparative results from other methods of treatment.

Aug 1, 1920

By D. Eugene Rannels, Yu-Chen Lee, John W. Swisher

"Inhaled dust particles of appropriate size contact cells of the alveolar region.' The acute response to coal dust appears to involve a variety of cell types, including alveolar epithelial cells, interstitial fibroblasts, both resident and recruited macrophages, and cells of the immune system. Direct and indirect effects of dust, which may be mediated by soluble factors,'' can initiate acute and long-term lung injury. While it appears that epithelial cell growth and differentiation, along with integrity of the epithelial basement membrane, may play a role in the long-term response to dust exposure, little is known of the role the alveolar epithelium may play in the progression of injury. The broad hypothesis that underlies these experiments is that short- and long-term consequences of coal dust exposure involve changes in structure and function of the alveolar epithelium and the underlying extracellular matrix. Recent studies show that coal dusts exert direct effects to modify pulmonary epithelial cell-extracellular matrix interactions in vitro.3EXPERIMENTAL PROCEDURESType II cells isolated on day 0 by density centrifugation and differential attachment4 were plated overnight in D MEM containing 10% fetal calf serum before exposure to anthracite dust PSOC 867 sonicated into culture medium (750 ug/mL).3 Synthesis of extracellular matrix proteins was determined on day 3 of primary culture, as detailed elsewhere. 5 Cells were removed from extracellular matrix by extraction with NH4OH and high salt. Extracellular matrix synthesis and fibronectin content were evaluated based on radiolabeling with 3 H-leucine and on Western blot analysis, respectively. Additional analytical methods and calculations are detailed elsewhere.3-5"

Jan 1, 1998

By Jack E. Fraley

The Bureau of Mines has successfully developed and tested a machine for spraying sealant onto coal mine roof and ribs. Dry material is transported pneumatically to a water-adding nozzle designed to provide dust-free spraying while being nonplugging and self-cleaning. The machine is self-cleaning, 35 inches in height, and capable of applying l/2-inch-thick coatings at over 1,000 ft2/hr.

Jan 1, 1978

By D. G. Kuehn

Mass spectrographic studies have been conducted on the positive ions and neutral species of glow discharges containing 1.0 pct S02 and 1.0 pct CO in helium. Measurements were conducted for gas pressures from 3.5 to 10.1 torr using both dc and 60-Hz ac excitation. The ion species that were observed included S+, SO+, SO+, 0+, O2+, C+, CO+, and CO2+ with lesser amounts of SO3+, (CO)2+, SCO+, and (SO?CO)+ or CS+2. Interpretation of the functional dependence of the various ionic and neutral species on pressure and applied power showed that CO reacted with the SO formed in the discharges to produce CO2 and sulfur. Deposition of elemental sulfur was observed in the plasma container.

Jan 1, 1973

By J. F. Barkley

As part of the work of serving as Chairman of Subcommittee 3, Health and Industrial Requirements, of the American Society of Mechanical Engineers' Committee on Air-Pollution Controls, the author assembled the following information on accepted maximum permissible concentrations of air pollutants from the standpoints of health, damage to vegetation, damage to property, and requirements of industrial processes. A search in technical literature was made followed by direct inquiry to all State governments as to their regulations. The subcommittee membership - G. D. Clayton, senior sanitary engineer, Public Health Service, United States Department of Health, Education, and Welfare, Detroit, Mich., Dr. L. Greenburg, commissioner; Department of Air Pollution Control, New York, N.Y., Dr. M. Katz, Defence Research Chemical Laboratories, Ottawa, Ontario, Canada, and Dr. H. H. Schrenk, research director, Industrial Hygiene Foundation of America, Inc., Mellon Institute, Pittsburgh, Pa. - reviewed the information and made very helpful comments and corrections.

Jan 1, 1954

By Richard A. Winters

In 1987, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied the 6,022-acre Spring Basin Wilderness Study Area (OR-005-009) in order to evaluate its mineral resources. The study area is in Wheeler County about 13 miles southwest of Fossil, Oregon. No mineral resources were identified. The area is underlain by volcanic flows, domes and sediments ranging in composition from olivine basalt to rhyolite of the Clarno and John Day Formations. There are three mining claims in the study area, all apparently located for lapidary material. Samples of agate were of poor quality. Four of 13 alluvial samples, two inside and two adjacent to the area, contained gold; content ranged from 0.0000097 to 0.00416 troy ounce per cubic yard. About 23 percent of the Wilderness Study Area is covered by oil and gas lease applications.

Jan 1, 1988

By Thomas V. Falkie, R. Venkataramani

Table

Jan 1, 1972

By Joseph W. Town

The Bureau of Mines conducted studies related to SO2 air pollution to determine attritioning rates, SO2 sorption rates, and sulfur loads that could be obtained on commercial alkalized alumina sorbent pellets. Fluidized-bed attritioning rates ranged from 0.025 pct/hr for alkalized alumina with a crushing strength of 4 kg to 0.075 pct/hr for 0.5 kg crushing strength mate¬rial. Airlift attritioning rates ranged from 0.50 pct/hr for 3 kg crushing strength alkalized alumina to about 3 pct/hr for 0.5 kg material. Attritioning rates for the commercial alkalized alumina were comparable to those obtained for sorbent pellets prepared in the Bureau of Mines laboratory. Sorption rates were related to S02 concentration in flue gas, temperature, and presence of nitrogen oxides in the gas stream. Sorption rates at 300° C were 0.35 X 10-6 gS/gp/sec (grams sulfur per gram pellet per second) in 0.045 pct so, gas, 5.1 x 10-5 gS/gp/sec in 0.34 pct SO2 gas, and 65 X 10-5 gS/gp/sec in 10 pct SO2 gas. For the 0.34 pct S02 gas, sulfur loads of 0.10 gS/gp (the projected load for regeneration) were obtained in 47 min at 130° C and in 116 min at 300° C. The presence of either NO or NO2 in the 0.34 pet S02 gas increased the SO2 sorption rates 2 to 3 times at 300° C, but had no effect at 130° C.

Jan 1, 1969

By L. D. Tracy

"This paper represents work conducted by the Bureau of Mines in cooperation with the Illinois Geological Survey and the Engineering Experiment Station of the University of Illinois.IntroductionThe present report covers conditions and mining royalties in District VIII of the coal fields of Illinois, as designated by the Illinois Geological Survey. The various districts have been described in the reports on the Illinois coal-mining investigations, carried on cooperatively by the Illinois Geological Survey, the engineering experiment station of the University of Illinois, and the U. S. Bureau of Mines. This district includes Vermilion and Edgar Counties, but as the coal-mining operations in Edgar County amounted to only 827 tons in 1923, the data here given have been confined to Vermilion County.A similar report on District VI (Williamson and Franklin Counties) has been issued as Serial 2722 of the Bureau of Minos.A description of geological and mining conditions, and a discussion of market and transportation facilities, have been included because these have an important bearing on the royalties specified and the general conditions of the lease.Mining ConditionsDistrict VIII is better known as the Danville district and in 1923 produced 4,177,000 tons of coal, or approximately L per cent of the total output for the entire State for that year, which was 79,300,000 tons."

Apr 1, 1926

By R. M. Santmyers

This paper represents one of a series of digests of foreign mining legislation that is being prepared in advance of a general report relative to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries . This interpretation of the mining legislation of Tunisia was prepared from a copy ( in French ) of the Mining Decree of Tunisia promulgated December 29 , 1913 , by the Resident General of France in Tunisia and effective January 1 , 1914. It is released subject to correction and amplification , if necessary , by the proper American diplomatic and consular officers , to whom it will be referred through the courtesy of the Department of State .

Mar 1, 1933

By W. L. Staker

Alternatives were developed to the conventional ammoniacal carbonate leaching-steam stripping procedure for recovering copper as an oxide from contaminated scrap metal. By entraining air bubbles in the leach solution, the copper dissolution rate was increased to 1.5 g/in2 of copper surface per hour, compared to 0.5 g/in2/hr produced by conventional agitation in stirred tanks. Using entrained nitrogen gas bubbles for agitation in conjunction with powdered sulfur not only resulted in rapid dissolution but also simultaneous precipitation of the copper from solution as a high-grade cuprous sulfide.

Jan 1, 1971

By Richard F. Hewlett

Use of digital computers makes possible a more efficient and complete analysis of data from a mineral deposit . This computer program was written and used during an investigation into the efficiency of methods of computing grade and tonnage of ore , wherein it was necessary to make repeated computations involving different combinations of data . This investigation was part of a continuing program of sampling methods research at the Bureau's Denver Mining Research Center.2-4 This program is designed to compute tonnage and average grade for 40 cutoff grades using either the statistical or polygonal methods . tational rate is from 200 ( input bound ) to 1,400 assays per minute , depending on the use of either individual ( one assay per card ) assay- interval length or

Jan 1, 1963

By Thomas V. Falkie, R. Venkataramani

Anderson, L. B., 1963, "Multiple Regression Techniques Correlate Experimental Data," Chemical Engineering, V. 70, N. 12, pp. 223-228. Aubert, E. J., Lund, I. A., and Thomasell, A. J., 1959, "Some Objective Six-Hour Predictions Prepared by Statistical Methods," Journal of Meteorology, V. 16, pp. 436-46. Barrett, A. L., 1958, "Alternating Current in Continuous Mining," Mechanization, V. 22, N. 9, pp. 83-86. Bower, A. B., Jr., 1970, "Bit Design: Key to Coal Cutting," Coal Age, V. 75, N. 7, pp. 70-72. Bower, A. B., Jr., 1971, Personal Communication dated April 29, 1971; General Electric Company, Mining and Metallurgical Products Department, Detroit, Michigan. Burt, C., 1950, "Group Factor Analysis", British Journal of Statistical Psychology, V. 3, pp. 40-75. Cady, L., Gertler, M., Gottsch, L., and Woodbury, M., 1961, "The Factor Structure of Variables Concerned with Coronary Artery Disease", Behavioral Science, V. 6, pp. 37-41. Cattell, R. B., 1965, "Factor Analysis: An Introduction to Essentials I. The Purpose and Underlying Models," Biometrics, V. 21, N. 1, pp. 190-215. Christensen, R. W., Heins, R. W., Babcock, W., and Tonn, R., 1971, "The Effect of Material Properties on Materials Handling Processes," Six Month Technical Report, (August 1971) to Advanced Research Projects Agency, U. S. Department of Defense; The University of Wisconsin. Collins, G., 1961, "Factor Analysis," Journal of Advertising Research, V. 1, N. 5, pp. 28-37. Cooley, W. W., and Lohnes, P. R., 1962, Multivariate Procedures for the Behavioral Sciences, New York: John Wiley and Sons, Inc. Cree, J. 0., 1956, "Power for Continuous Mining," Mining Congress Journal, V. 42, N. 10, pp. 49-52. Draper, N. R., and Smith, H., 1966, Applied Regression Analysis, New York, John Wiley & Sons, Inc. Griffiths, J. C., 1966, "A Genetic Model for the Interpretive Petrology of Detrital Sediments," The Journal of Geology, V. 74, N. 5, pp. 655-672.

Jan 1, 1972

By R. E. Lindstrom

Electrooxidation techniques were investigated on a bench scale by the Bureau of Mines to determine the applicability of the process for extracting molybdenum and rhenium from low-grade molybdenite concentrates. Parameters affecting the extraction, such as pulp density, power consumption, reagent requirements for pH control, and electrolytic cell configuration, were studied. Molybdenum and rhenium extractions of 98 to 99 percent were achieved from several concentrates containing 4.76 to 28.6 percent molybdenum and 180 ppm to 1,000 ppm rhenium. Optimum results were obtained by maintaining pH values between 5.5 and 7.0 during electrolysis and allowing the final pH to rise to about 8.2. Reagent consumption was 4 to 6 pounds of sodium carbonate per pound of molybdenum extracted. The power consumption declined from a range of 12 to 25 kilowatt hours per pound of molybdenum extracted with immersion electrodes to 9.7 kilowatt hours with a bipolar flow-through cell; however, molybdenum extraction was independent of cell configuration.

Jan 1, 1973

By E. P. Youngman

In this island, which is a Crown colony of the British Empire, and where remarkably extensive remains of ancient mining operations-- mainly for copper--exist, the mining law of Turkey governs, rith such modifications as were made necessary by the transfer of the country in 1878 from Turkey to Great Britain, and with such fer ameliorations thereof as have since been ordered by the local authorities. The Turkish law to which Van agenen refers is, no doubt, "2 Shaban, 1285," which though subsequently repealed with respect to Turkey is still in force in Cyprus, inasmuch as the mines regulations (amendment) law of 1925 "is to be read in connection with 2 Shaban, 1285" (articles 61 to 67 of which were repealed by the law of 1925): In the preparation of this digest; access was had to the mines regula- tions (amendment) Iaw, No. 5 of 1882; which Van Wagenen does not mention. Other Cyprian laws, passed since the publication of Van Wagenen's work in 1918, are the following: Eines regulations (amendment) law, 1925, No. 12 of 1925; mining-prospecting permits; notification, No. 539 of 1927; mines regu- lations 1926, No. 1006 of 1926; mines regulations (amendment) rules of court, 1926, No. 144 of 1926; mines regulations (amendment). 1a, 1928, ko. 3 of 1528 (as amended by No. 32 of 1928). Most of these làrs are concerned with the regulation of actual mining operation--safety and sanitary provisions; and, therefore, they ado little important information. The Cyprian Government's official publication says: It is considered that the laws regulating mining in Cyprus are inadequate and antiquated, and a thorough revision is necessary to bring them up to a standard of modern mining practice and to encourage mining ventures in the island. As a preliminary to this the mines regulations, 1926, were issued to govern the workings of the larger mines; and serious attention is now being given to the regulating of prospecting, quarries, machinery in mines, and generally to the bringing of mining in Cyprus into conformity with the other mining countries of the world.

Jan 1, 1933

By Van E. Shaw

Bastnaesite is a natural rare-earth fluorcarbonate of the cerium group that affords an abundant and high-grade source of the lighter rare-earth elements. A simple and efficient method has been developed by the Bureau of Mines for extracting rare-earth compounds from this mineral. Digesting of a flotation concentrate with sulfuric acid converts the rare-earth compounds from fluorcarbonates to sulfates. Action of the acid releases gaseous com-pounds of fluorine and silicon, leaving the sulfated material free of these elements; carbon dioxide from carbonate decomposition is eliminated at the same time. Calcining the sulfated material at 1,200° F. renders the gangue constituents insoluble, whereas the rare-earth sulfates are left in water-soluble form. Leaching with water yields a solution of pure rare-earth sulfates. Bastnaesite could become prominent as a source of cerium-group rare-earth elements. It is rich in the light rare-earth elements and comparatively easy to process; reserves of the mineral are extensive enough to supply a greatly expanded market for many years.

Jan 1, 1959