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By Mark I. Copeland

Bureau of Mines researchers investigated the combined effect of copper and tin additions on the mechanical properties of hot-rolled steels. Wrought steels containing 0.2 wt-pct C and up to 0.2 and 1.0 wt-pct Sn and Cu, respectively, were made and evaluated by conducting tensile and impact tests and electron-beam microprobe and electron microscopy examination. Tin additions did not significantly affect the tensile properties of steel at different copper contents in the hot-rolled condition. Tin lowered the copper content at which strengthening by copper precipitation normally starts, 0.8 wt-pct, and decreased the strength of steel aged at 1,022° F (550° C). The most adverse effect of tin was lowering the notch toughness of steels at most copper contents.

Jan 1, 1976

By G. L. Fitzpatrick

Future applications of seismic holography to "seismically transparent phase objects," such as rock inclusions, fracture zones, liquid-filled cavities, etc., will require techniques to improve the poor image contrast generally characteristic of these objects. Although conventional phase-contrast enhancement techniques could be used, these methods involve additional optical elements such as quarter-wave spatial filters. Owing to the anticipated practical difficulties of properly alining such optical devices and properly locating poorly defined image planes and filter planes, this approach is not considered to be well-suited to the case of seismic holograms and their laser reconstructions. Results similar to those achieved with spatial filters may be obtained without filters by specially processing the seismic hologram data. The new process, which is an extension of Gabor's subtraction holography, achieves an improvement in contrast by an interferometric technique. The process involves adding a ?before" hologram without an object present to a 90° phase-shifted "after" hologram with the object present. Then, the combination is reconstructed with a laser or by computer. Not only is the image contrast improved in such processed holograms, but the images are also phase-contoured. In general, the latter feature is not to be expected when conventional phase-contrast enhancement techniques are employed. The new technique is experimentally verified by examining computer-generated synthetic seismic holograms rather than by examining actual seismic field data. However, results of this study are directly applicable to real seismic data and should prove useful in future applications of seismic holography.

Jan 1, 1973

By E. Chin

The domination of Bangladesh's mineral industry by natural gas was in for some possibly significant changes. A modest flow of crude oil was struck in a gas development well in the northeastern corner of the country. This was the first commercial flow of crude oil in Bangladesh. All crude oil was being imported, which cost a significant proportion of the nation's foreign exchange earnings. The development of an oilfield producing only a few thousand barrels per day would be a welcome help to the economy. Additional exploration at a 1985 coal discovery in the northwest indicated a considerable reserve of good-quality coal at a depth suitable for mining. If the coal is mined, it would be a boon to the local economy because natural gas was not available in the area.

Jan 1, 1988

By T. A. Sullivan

The use of sulfur combined with either sand or waste copper tailings was investigated by the Bureau of Mines as a substitute for a good graded aggregate in asphalt paving materials. The research was part of a utilization program to develop meaningful uses for a projected oversupply of sulfur. Many sections of the country lack good aggregate for paving but do have available sources of sands and sulfur. The development of paving mixtures of desert sands or tailings with sulfur and asphalt was accomplished in the laboratory and tested by laying small paving test sections. Three types of material were studied for use with the sulfur and asphalt. They were (1) a concrete sand similar in gradation to river or beach sands, (2) desert blow sand, and (3) waste copper tailings. Desert blow sand and waste copper tailings are much finer than concrete sand. Mix designs were established for the three types of materials, sulfur, and asphalt used in the paving materials. The best mix designs were as follows, in weight-percent: 80.5 concrete sand, 13.5 sulfur, and 6 asphalt; and 77 either blow sand or tailings, 17 sulfur, and 6 asphalt. Small-scale testing showed that these mixtures were suitable paving materials but would require specialized equipment for transporting and laying. The chemical modification of sulfur to obtain properties that would allow placement of these materials with normal asphalt paving equipment was studied. Results indicate that reacting sulfur with dicyclopentadiene before adding it to the paving mixture was effective in modifying the sand-sulfur-asphalt paving so it could be placed and rolled with conventional equipment.

Jan 1, 1975

By A. S. Peck

This report presents the results of a cooperative study between the Bureau of Mines and the University of Utah to define the mechanism involved in the adsorption of oleic acid and sodium oleate on fluorite, calcite, and barite, using an infrared spectrophotometer for identifying and measuring the adsorbed reagents and reaction products. Fluorite, calcite, and barite react with oleic acid and sodium oleate in a water system, forming chemisorbed and solution products. The chemisorbed species is a surface mineral cation-collector anion salt, Chemical analysis of solution resulting from the adsorption reaction indicates that the adsorption process causes displacement of mineral anions, namely, fluoride, carbon ate, and sulfate from the surface of these minerals.

Jan 1, 1963

Coal research and technologic work by the Bureau of Mines covers a broad program of investigation aimed at conservation and utilization of this important natural resource. Conservation is served by a constant search for higher efficiencies in mining, preparation, and use. Increased utilization is sought through various projects that probe new ways to use coal and expand existing coal markets. This report, the twenty-eighth in the series,3 gives the highlights of Bureau of Mines coal research and technologic work in 1963. The scope and complexity of the program makes it virtually impossible to report all progress on every project, even tor a 12-month period. Full insight into each project can be gained only through intensive review of basic objectives, past accomplishments, and current status of the work. Details of the work are given in numerous publications issued by the Bureau and its laboratories and centers located throughout the country.

Jan 1, 1964

Coal research and technologic work by the Bureau of Mines covers a broad program of investigation aimed at conservation and utilization of this important natural resource. Conservation is served by a constant search for higher efficiencies in mining, preparation, and use. Increased utilization is sought through various projects that probe new ways to use coal and expand existing coal markets. This report, the twenty-eighth in the series,3 gives the highlights of Bureau of Mines coal research and technologic work in 1963. The scope and complexity of the program makes it virtually impossible to report all progress on every project, even tor a 12-month period. Full insight into each project can be gained only through intensive review of basic objectives, past accomplishments, and current status of the work. Details of the work are given in numerous publications issued by the Bureau and its laboratories and centers located throughout the country.

Jan 1, 1964

In the spring of 1944 the Congress passed Public Law 290 (58 Stat. 190, 30 U. S. C. Sec. 321) "authorizing the construction and operation of demonstration plants to produce synthetic liquid fuels from coal, oil shales, agricultural and forestry products, and other substances, in order to aid the prosecution of the war, to conserve and increase the oil resources of the Nation, and for other purposes." Section 2 reads: "In order to carry out the :purpose of this act, the Secretary of the Interior is authorized- (a) to conduct laboratory research and development work, and, with pilot plants and semi-works plants, to make careful process engineering studies, along with structural engineering studies, in order to ascertain lowest investment and operating costs necessary to determine the best demonstration plant designs and conditions of operation;

Jan 1, 1948

By E. J. Babcock, W. W. Odell

The Bureau of Mines since its establishment has always taken an active interest in the utilization of lignite and in the development of the lignite dep'osits of the United States. Extensive lignite fields occur in the west central States, notably in North Dakota, Montana, Wyoming, Colorado, and Texas; there are smaller areas in several other States, some of which are widely separated. The total area of the deposits and the total amount of lignite in these several districts are so enormous that the economic value is seldom recognized. To the people of ·the west and west central regions, however, the larger utilization of lignite, in whatever form it may be, is of fundamental importance, and any new methods or uses that promise to open these great lignite fields for more general and more efficient use deserve careful study. Although these lignite deposits underlie areas of thousands of square miles, their development and general utilization has been rather slow. This is no doubt partly because many of the districts are not thickly settled or highly developed in manufacturing industries, but is largely because lignites, from their peculiar physical and chemical characteristics, are low-grade fuels. Most of the lignites in these areas are imperfectly developed coals; many have a more or less woody structure; some belong to the brown-coal type; and others are darker, denser, and more homogeneous, approaching subbituminous coal. The people living in the regions in which these vast deposits occur, especially in the west central part of the United States, are vitally interested in every effort toward bettering lignite as fuel and aiding its wider utilization.

Jan 1, 1923

By Lulie H. Crump

Salient historical data on consumption of fuels and energy have been summarized by State and census district for the years 1960 through 1972. This Information Circular covers States east of the Mississippi, and Information Circular 8705 covers States west of the Mississippi. These data replace previously published compilations of energy consumption statistics by States and districts. Future annual studies are planned using the same Btu conversion factors applied in these two. Information Circulars.

Jan 1, 1976

By E. J. Schneider

In view of the growing commercial interest In the higher boiling fractions of low-temperature tar, a study of the literature has been undertaken to obtain as many data as possible regarding the properties of possible pure constituents. The following substances have been studied: THREE-ORTHO-XYLENOL (1, 2-DIMETHYL-3-HYDROXYBENZENE) Detection By the isolation of the silver salt of 1, 2-dimethyl-3-phenoxyacetic acid.

Jan 1, 1930

By M. A. Elliott, F. W. Brown

"INTRODUCTION During the recent war the Bureau of Mines, at the request of one of the armed services, investigated the hazards that night be encountered 5n handling perchloric acid, particularly if spilled on certain materials. The hazardous nature of perchloric acid when mixed with reducing agents had been known qualitatively, but it was desired to obtain quantitative data on the explosion hazards of such materials. Accordingly, tests were made to determine the sensitivity of mixtures of perchloric acid and oxidizable materials to initiation by heat, impact, sparks, flame, and explosive impulses. This report summarizes the results of those tests.PROPERTIES OF PERCELORIC ACIDAnhydrous perchloric acid is a colorless,hygroscopic, volatile, mobile liquid that fumes in the air. The anhydrous acid is unstable at ordinary temperatures, and therefore the commercial acid is a water solution containing either 60 percent or 70 percent by weight of the anhydrous acid. The commercial acid is widely used in chemical analysis, frequently to oxidize organic material. If proper precautions are not observed, such an oxidixation may become exceedingly rapid and result in an explosion. Several such explosions involving the acid are mentioned in the literature. 4, 5, 6/"

Jan 1, 1948

Quickly and cheaply consolidate underground slimes to facilitate their use as backfill and permit their easy handling for other reasons. Approach: The slurry containing slimes is pumped into active stopes and electrokinetically dewatered to provide consolidated back fill. How It Works: To densify slimes electro-kinetically two electrodes are placed in the material to be dewatered and densified. Typically, the electrodes are pieces of wire mesh fencing. One is placed on the bottom, and the other is suspended in the slurry near the surface. Figure 1 is a simplified section of a test. A d-c voltage of 100 to 400 volts is applied across the slurry. This causes the solid particles which are in suspension in the water (usually these are negatively charged) to migrate toward the anode; simultaneously, the water moves toward the cathode. Water immediately adjacent to the negatively charged solid particle surfaces contains an excess of dissolved positive ions. When these ions are attracted to the electrode and move towards it, they also exert

Jan 1, 1976

By Laurence F. Kelley

This paper is one of a series being prepared by the United States Bureau of Mines on shaft-sinking methods and costs at individual operations in various mining districts of the United States. The methods and costs described herein are those of The Consolidation Coal Co. at one of its operations in the Tug River district, McDowell County, W. Va. ACKNOWLEDGMENT The author is indebted to Frank R. Lyon, vice-president, Thos. G. Fear, general manager of operations, and Chas. Enzian, chief engineer, of The Consolidation Coal Co., for valuable assistance and collaboration in the preparation of this paper. W. A. Cole, manager of the E. J. Longyear Development Co. furnished valuable data on methods and performance averages.

Jan 1, 1932

The Black Hills Mineral Atlas briefly summarizes all pertinent date available on the mines and mineral deposits in the Black Hills that have been explored, developed, mined, or located. The purpose of the atlas is threefold: First, from available date the general potentialities of the Black Hills region can be determined, although it is not possible to calculate actual ore reserves; second, it will provide the necessary basic information regarding a given property or commodity for further detailed study; and third, the compilation is a comprehensive directory of Black Hills deposits.

Jan 1, 1954

By Mackenzie Burnett

This program was initiated by USBM to quantify the respirable dust problem caused by the use .of roadheaders in underground metal/nonmetal mines with special emphasis on this problem in uranium mines. The contract called for the development of methods or equipment to alleviate the respirable dust and to implement the solution in a mine. Attempts to quantify the dust problem were made in the following way: survey of MSHA records, survey of state mine enforcement agencies, survey of mine records, dust measurements taken at two mines using roadheaders. The results of this study are not conclusive due to very limited and sometimes less than useful data; however, the study does indicate that a serious dust problem could and may exist. If and when roadheader use becomes more popular, it is almost certain that development of dust control procedures and equipment will be necessary. This contract was concluded without developing this equipment since only one roadheader is currently in use in an American uranium mine and the mine prefers not to participate in the program at this time. This report discusses the available data concerning respirable dust problems and presents a solution which can potentially help to solve the problem. The solution requires the use of blowing ventilation, on-board dust extraction at the source, and filtration, as well as continued use of water sprays. The on-site tuning of such a system is necessary to demonstrate the degree of improvement possible.

Jan 1, 1981

By F. R. McDonald

The proton NMR spectra of 32 pyridines in two solvents, carbon tetrachloride and benzene-d6, are presented. The chemical-shift and differential-shift values are correlated with the substitutent position and with the solvent media. The ring protons and the protons on alkyl substituents are tabulated. The paramagnetic shift of the protons adjacent to the nitrogen is discussed, and a proposed structure for the pyridine-benzene complex that is consistent with the observed anomalous paramagnetic shift is presented. The utility of the data in the identification of pyridine compounds found in shale-oil naphtha is demonstrated.

Jan 1, 1971

By Thomas J. Peters

The U.S. Bureau of Mines and the U.S. Geological Survey are responsible for the evaluation of the mineral resources and potential of further planning areas included in the U.S. Forest Service Roadless Area Review and Evaluation (RARE II) program. The Bureau of Mines primarily evaluates mineral deposits and prospects within the areas. The Geological Survey naps the area's geology and conducts geochemical sampling. Evaluations are in conformance with the Forest and Rangeland Renewable Resources Planning Act of 1974 as amended by the National Forest Management Act of 1976. The Hauser RARE II area, which consists of 7,600 acres (3,100 ha) within the Cleveland National Forest, is in southern San Diego County, California. The area, which forms the north slope of Hauser Canyon, ranges between 1,600 and 3,919 ft (490 m) in elevation. It is sparsely to densely covered with desert shrubs. The area is underlain by granitic rocks of the Peninsular Ranges batholith.

Jan 1, 1983

By Berk. A. A.

"INTRODUCTION Corrosion of sections of piping used in steam-heating systems is frequently regarded as unavoidable, and periodic replacement is provided. Surfaces exposed to newly condensed steam appear to be especially vulnerable to attack. As an added nuisance, solid products of the corrosion tend to accumulate, plugging return lines.The trouble is ascribed in the main to carbon dioxide and oxygen 3/ 4 / 5/ 6/ dissolved in the condensate. When oxygen is the principal factor, the corrosion usually is characterized by pitting. Carbon dioxide tend3 to cause an acidic condensate which dissolves the metal more uniformly and produces the familiar failure at threaded areas where the piping is relatively thin, and where high stress may tend to acceletate the attack. Carbon dioxide enters the system with the feedwater, generally in a combined form such as carbonates and bicarbonates. Oxygen enters both with the raw feedwater-and as air leaking into lines under partial vacuum. The larger central-heating plants have sought to reduce corrosion by eliminating these gases as much as possible. A smaller plant ordinarily lacks the equipment and technical supervision required for this purpose."

Jun 1, 1944

By H. E. Hilliard

A method was investigated for detecting and counting filamentous iron bacteria in open recirculating cooling systems. It is simple and fast and does not require trained microbiologists. Samples from 26 systems were examined. Cells were cultivated on commercially prepared ready-to-use media. Cultures grew well on this medium and were identified as filamentous iron bacteria by microscopic examination and by their ability to deposit iron using the prussian blue reaction.

Jan 1, 1976