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By R. A. Guereca

Preliminary to an experimental study of selected physical properties of helium and related gases) the Bureau of Mines Helium Research Center conducted a data-gathering literature survey. This report combines the results of the 1961-63 literature search into a usable format. The data accumulated on the physical properties are presented in tables and graphs. The data in the tables were chosen for exact representation and comparison of specific values. An attempt was made to select the most reliable and consistent value available for a given property without extensively analyzing each source reference. The methods of evaluation are discussed later. The graphs show trends and anomalies which may be obscure in tabular form. (Reprints of the graphs) with the scale grid enlarged 2 1/2 times) are available upon request through the Research Director) Helium Research Center.) The literature search was conducted using Chemical Abstracts as the primary reference source with additional information drawn from Applied Science and Technology Index) Chemical Reviews) Physics Review) Science Abstracts (Physics») and other abstracting services. Part of the data included in this report have been tabulated previously by others (£-1).5 In a few areas) the sources of information are scarce and obscure (for example) refractive index and dielectric constant). The search was extensive; however) some sources

Jan 1, 1967

By H. J. Hager, B. W. Gandrud, G. D. Coe

"INTRODUCTION The reduction of washery losses of marketable coal is a phase of coal preparation important to many of the Alabama coal producers. The problem has wide scope, and this report deals with but one of its several aspects. The investigation on which this report is based was made by the Southern Experiment Station of the Bureau of Mines with the cooperation of the Alabama By-products Corporation and the University of Alabama. The Alabama Byproducts Corporation provided samples of table middlings from its Colta washery on the Mary Lee bed at Flat Creek, Ala.PRACTICE AT THE COLTA WASHYAt Colta run-of-mine coal is crushed in a hammer mill in closed circuit with 5/16-inch square-mesh vibrating screens and tabled without classification on eight rectangular-deck wet tables. The coal is more friable than the bone normally present, and hence the bone is concentrated in the coarser sizes. An unclassified feed of this character can not be tabled with high efficiency to low ash content because of the sizing action of a concentrating table, which is such that when the tables are adjusted to exclude the coarse bone from the washed coal, a large amount of fine coal is lost in the middlings. At the time this investigation was undertaken there was no market outlet for middlings, with the result that middling products had to be discarded with the refuse."

May 1, 1939

By A. Gene Collins

The Bureau of Mines undertook research to determine the bromide and iodide content of Mississippi and Alabama oilfield waters of the Tertiary and Cretaceous Period to determine genetic relationships of the ions, to determine their origin, and to determine their genetic relation to petroleum. The 280 samples were analyzed after a pretreatment to remove interferences. The iodide was oxidized to iodate and was titrated with thiosulfate. The bromide was oxidized to bromate and was determined iodometrically. A computer was used to calculate the correlation coefficients of iodide to bromide and to other ions. The other ions are sodium plus potassium, calcium, magnesium, chloride, bicarbonate, and sulfate. The mineral content of the samples ranged from 52 to 1,760 mg/l for bromide and from 2 to 65 mg/l for iodide. The mean bromide-to-chloride and iodide-to-chloride ratios were 0.0065 and 0.0002. The correlation coefficient matrix and linear plots indicated a definite bromide-to-calcium relationship for the brines investigated.

Jan 1, 1967

By Thomas M. Barczak

Wood cribs are used extensively by the mining industry to stabilize mine openings. While the cost per crib is relatively low, their extensive use can result in annual mine costs of over $1 million. In an effort to improve the utilization of these supports and to reduce ground control hazards, the U.S. Bureau of Mines has developed engineering methods to assist mine operators in wood-crib design and employment. Design and employment criteria are established based on the strength, stiffness, and stability of the crib structure in relation to the load conditions imposed by the mine environment. Models have been developed based on full-scale tests in the USBM's Mine Roof Simulator that compute the capacity of wood cribs of various configurations and material constructions as a function of displacement of the crib structure due to roof-and-floor convergence. These models permit the comparison of the loading characteristics and costs of employment of different crib designs, and in conjunction with roof behavior models, provide a means to determine the optimum design and employment strategy.

Jan 1, 1993

By G. E. McElroy

The purpose of tins paper is not to present new date on the pressure losses due to bends and chances of area in mine openings through which air flows, but rather to correlate existing data, determined mainly on small duct systems and expressed in a variety of ways, according to uniform methods that facilitate their use in pressure-loss computations. These are required in such, air-flow problems as determining the quantity that will flow through is mine openings under a certain pressure difference or, conversely, the pressure difference that will be required to maintain a certain rate of flow. Air flowing through h ducts, such as mine airways, encounters resistance to flow due to interference of the individual air streams with each other caused by the wall surfaces. The result is that part of the kinetic energy of the flowing stream is converted to heat; and constant renewal of the kinetic energy from the total energy of the flow is required to maintain it. This process manifests itself by a decrease of the total pressure (static pressure plus velocity pressure; of the air in the direction of flow; in order that flow pray occur, there must necessarily be a differences in total pressure between the two cads of the air-ay equivalent to the pressure losses occasioned by the flow, which automatically adjusts itself in magnitude to the pressure difference maintained.

Jan 1, 1932

By Gerald T. Homce

A system capable of monitoring mine electrical power systems and detecting impending component .failure could significantly improve power system safety and reduce unscheduled equipment downtime. Such monitoring would require a method of evaluating electrical parameters, calculated from terminal values, for indications of component deterioration. The U.S. Bureau of Mines has targeted electrical failure of squirrel cage induction motors and examined the use of mathematical models to aid in this evaluation. The initial stage of this work is complete, and has produced polynomial networks called adaptive learning networks (ALN's) that can detect and quantify winding insulation leakage simulated on laboratory motors. In this modeling process, empirical data from laboratory motors were used to select the electrical parameters most significant for assessing? motor conditions, and mathematical expressions relating these parameters to simulated deterioration were formed. ALN's developed thus far can process readily measured motor terminal information and quantify power and current levels of laboratory-simulated leakage to within 1% and 3% of full load values, respectively, for motors in the 10-to 150-hp size range. The next stage of this research is validation of these ALN's for actual motor failures; this stage is currently underway, using accelerated life testing of laboratory motors.

Jan 1, 2010

By H. E. Powell

The magnetic susceptibility, the geographical source, and associated minerals are given for 44 copper-, 26 lead-, and 19 zinc-bearing minerals. Of the 44 copper minerals/ all had a susceptibility of less than 15 X 10-6 cgs, and about 20 percent of them were diamagnetic. Of the 26 lead minerals, all had a susceptibility of less than 11 X 10-5 cgs, and almost half of them were diamagnetic. And, of the 19 zinc minerals, all except four had a susceptibility of less than 9 X 10-6 cgs, and about one-fourth of them were diamagnetic.

Jan 1, 1968

By Larman J. Heath

Liquid incendiaries were burned within the interstices of several different types of sandstone cores to determine the technical feasibility of increasing sandstone permeability by this method. Fuel-oxidant mixtures were tested in 186 cores; six cores exploded when ignited. In virtually all instances, the explosion completely pulverized the sandstone cores. In addition n those cores damaged by explosions, 24 cores were fractured so severely that permeability tests were impossible. Although combustion gener¬ally increased the permeability, specific mixtures at given pressures were inconsistent in their ignition and burning behavior. Tests indicated that the heat of burning incendiaries significantly increased sandstone permeability. The improved permeability ratios were usually less than 2, but one was 10.3. Permeability alteration by other in situ methods was not as effective as that by flame propagation.

Jan 1, 1971

By N. S. Dalal, B. Jafari, F. H. Y. Green, V. Vallyathan

"INTRODUCTIONThe mechanistic details of the biological events leading to coal workers pneumoconiosis (CWP) are not yet fully understood, despite several decades of extensive epidemiologic1.2 and laboratory studies.2-6 Epidemiologic studies1.2 have shown, for example, that the incidence and severity of CWP differ markedly in the different regions and mines at comparable exposures, but laboratory investigations2-6 have demonstrated only partial correlation of the epidemiologic data with the differences in the mineral composition and the rank of coal mined. In particular, while epidemiologic data indicate1.2 direct correlation of the· prevalence and severity of CWP with the rank (i.e., % carbon content) of coal, this correlation has not been established by laboratory4'6 and animal exposure3 studies. In order to explain these results, in 1980 Artemov and Reznik' suggested that perhaps they arise from the fundamental differences in the surface properties of the coal. dusts inhaled by the coal miners and those used in the laboratory studies: while the miners inhale freshly fractured coal particles, henceforth called the 'fresh' coal dust, the laboratory studies generally utilize 'aged' coal dusts (i.e., dusts that have been stored for many days or even longer). Reznik and Artemov' used electron spin resonance (ESR) spectroscopy to show that the mechanical crushing of some Soviet Union coals generated organic free radicals and that the concentration and the decay times (hence the reactivity) of these radicals were higher for the coals of higher ranks. Since some of the radicals decayed within a few minutes in air, the authors surmised that while these radical species could lead to certain specific pathogenic reactions at the sites of mining operations, this might not be the case in the laboratory studies, due to the conventional use of 'stored' dusts which would be expected to contain significantly smaller free radical concentrations. This is consistent with the recent findings that, standardized, aged coal dusts exhibit minimal cytotoxicity. 8While the above mentioned work of Artemov and Reznik7 did suggest a possible new clue to the pathogenesis of CWP (i.e., the role of the coal based free radical species), no direct biological/cytotoxicity data were provided to show that 'fresh' coal dusts were, indeed, more pathogenic than the 'stale' ones. Because of the rather significant implications of the Artcmov-Reznik hypothesis to the understanding of 1hc biochemical mechanism and, hence, the strategies for the eventual containment of CWP, we have initiated a comparative study of the free radical formation and cytotoxicity properties of freshly crushed coal ·particles. As done by Artemov and Reznik, 7 we have used the ESR technique as the direct method of measuring the concentration and decay kinetics of the coal based free radicals. Our preliminary ESR studies on two Pennsylvania coals, a bituminous (carbon content 72 % ) and an anthracite (95 % carbon) coal, have confirmed the Artemov-Reznik finding that the crushing-induced free radical sites are higher on the coals with higher carbon content (i.e., higher rank).9-11 In the present work we describe our more recent results of a parallel study of the time dependence of the decrease in the free radical content of a freshly made anthracite dust (as measured via ESR) and that of the dust's cytotoxicity potential as measured by the extent of hemolysis of (sheep) erythrocytes. We have also investigated the effects of free radical scavengers on the cytotoxicity potential of the dust and deduce that indeed the free radicals could play a significant role in the initial events in the mechanism of the cytotoxic effects due to the inhalation of coal dust inhalation."

Jan 1, 1990

By E. H. Crabtree

This paper, describing the milling practices at the White Bird concentrator, Picher, Okla., is one of a series on milling practices being published by the Bureau of Mines. The concentrator of the White Bird mine, Canam Metals Corporation, is located in almost the geographical center of the present Picher mining cam' in the Tri-State district, one-half mile east of the town of Picher, 1 mile south of the Kansas State line, and about 18 miles west of the Missouri State line.

Jan 1, 1930

By David J. Kusler

The Bureau of Mines reviewed current technology in the refractories consuming industries and evaluated the impact of changes in technology on the supply and demand of refractories. Literature was searched and contacts were made with leading consumers and producers of refractories. The distribution of refractories by value of shipments to users was surveyed. The report shows that the percentage distribution of refractories sales to the consuming industries has remained essentially constant during the last decade but that substantial changes have occurred in the relative distribution of types of refractories. The trend in pyroprocessing technology in recent years has been toward higher temperatures, which require more costly refractories. This fact is reflected in the impressive gain in the dollar value of refractories sales, which in 1968 was about one-third greater than in 1960, and the rapid growth of refractories based on high-alumina, magnesia, zirconia, carbon, and other materials, at the expense of fire clay, silica, and chrome- based refractories. An appendix to the report contains refractories value and shipment data tabulated in a manner by which trends in the distribution of refractory types can be observed from 1955 to 1968. In addition, unit values are presented on a per-ton basis for comparison.

Jan 1, 1970

By Harry H. Ku

In December 1975, a report entitled "An Evaluation of the Accuracy of the Coal Mine Dust Sampling Program Administered by the Department of Interior" [1] was prepared by the Analytical Chemistry Division of the National Bureau of Standards (NBS), in response to a request by Senator Harrison A. Williams. Chairman, Committee on Labor and Public Welfare. The report attempted to evaluate the adequacy of (1) the personal sampler unit used to measure the coal dust concentration in the mines, (2) the procedures used by the Department of Interior (DOI) to analyze the dust samples obtained from mine operators, and (3) any recent studies made by the Department or private industry concerning the coal dust sampling equipment. Recommendations in the report of NBS included continued research efforts by the appropriate organization to correct the personal sampler deficiencies and to consider the use of area or stationary samplers as a supplement to the personal samplers. Concurrent with the NBS report cited above, the General Accounting Office (GAO) also issued a report in December, 1975 [2], suggesting that improvements are still needed in coal mine dust sampling programs and procedures relating to penalty assessments and collections. Among recommendations made by GAO, the following paragraph specifically called for actions by the agencies involved:

Jan 1, 1979

By S. P. Holt, Robert S. Sanford

"INTRODUCTION The wartime demand for iron ore and alloy steel on the west coast revived interest in iron reserves in western United States and Alaska. Magnetite was known to have been the most abundant metallic mineral at some of the old copper mines on Prince of Wales Island. In the summer of 1942, the Bureau of Mines began a program of preliminary investigation followed by core-drilling two magnetite deposits on the island.The Poor Man iron deposit on Kasaan Peninsula, Prince of Wales Island, Southeastern Alaska, was examined in August 1942 by Robert L. Thorne, associate mining engineer of the Bureau of Mines, and John C. Reed and B. N. Goddard, geologists of the Federal Geological Survey in September 1942 the area was mapped geologically and a magnetic survey was made by the Geological Survey. In October and November 1942, a more thorough preliminary examination, which included cleaning out and sampling old adits and trenches, was made by thesenior author, Robert L. Thorne, and Aner W. Erickson, engineers of the Bureau. J. G. Shepherd, a consultant of the Bureau, spent two weeks in March and April 1943 investigating the Poor Man and other deposits on Kasaan Peninsula. Core drilling was completed in June 1943.L. A. Warner, of the Geological Survey, examined all cores and interpreted structural data revealed by the drilling."

Oct 1, 1946

By J. H. Rose

This paper describing the milling practice at the Magma Copper Co., Superior, Ariz., is one of a series being prepared by the Bureau of Mines on milling methods and costs in the various mining districts throughout the United States. ACKNOWLEDGMENT The authors wish to acknowledge their indebtedness to William Koerner, general manager of the Magma Copper Co., for permission to prepare this article; to J. S. Garrott, former mill superintendent, for the historical facts; and to Walter Cooksley, general foreman, for his assistance in obtaining the data.

Jan 1, 1930

By Charles Will Wright

This paper has been written to aid the owner of a small gold mine or prospect in preparing a report on his property for the purpose of interesting capital. If an owner can afford to do so, he should employ a mining engineer of recognized standing and experience to examine and report on his property, but many owners of small -mines and particularly of prospects cannot make the expenditure required for this. Further, many of them do not know how to prepare a description which will cover those features of a deposit on which a potential investor promises his opinion as to its worth. If such an owner is convinced that he possesses an orebody of sufficient grade and size to warrant the required expenditure for a thorough investigation and wishes to present his property to prospective investors, then the following suggestions concerning the proper way to sample his deposit, estimate the tonnage of developed and probable ore, and prepare a report may be of assistance.

Jan 1, 1933

By John C. Feeley

The methods used and the funds available for the development and oper- ation of shall mines and the reopening of small abandoned mines frequently present problems that tax the ingenuity and resourcefulness of the mining engineer far beyond that required in the mass production from large deposits. The objective of this paper is to describe in considerable detail the means whereby engineers have solved local problems in reopening an abandoned mine at which equipment, facilities, and funds were limited... The Etowah Coal & Iron Co. Gadsden red-iron-ore mine at Gadsden, Ala., 18 of interest in this category since it is the only independent red-ore mine under active development in the State. All other red-ore mines in Alabama are owned or controlled by the large iron or steel companies. The The mine, located on the southwest end of Shinbone Ridge in the outskirts of Gadsden lies in an ares once productive. but now idle, for many years. ore is relatively highgrade compared with that in the Birmingham area, but the bed is thin and somewhat lenticular. The presence of a large blast furnace at Alabama City, 3 miles from Gadsden, and the growing scarcity of red-iron ore supplies for it offered inducements for reopening the mine in 1946. Up to the time this circular was prepared (1947) only a small quantity of ore (about 1,500 tons) has been produced and shipped to the furnace. A force of 14 men was employed in sinking the main slope and developing a third "lift" (a local term for level) 100 feet below the old mine workings.

May 1, 1949

By F. F. Aplan

Separation of the slightly soluble minerals (Ksp? 10-10), one from the other is one of the more difficult tasks confronting flotation engineers. This study has focused on means of separating such prominent members of this class as scheelite, fluorite and calcite from one another. Some experimental work has also been done on the minerals magnesite, dolomite and apatite. Carboxylic acid-type collectors are commonly used industrially to float all of these minerals. Thus, the problem at hand is to ascertain means of achieving selectivity between minerals known to respond rather similarly in flotation. Four techniques have been proposed for the separation of minerals of this class from each other: 1. Control of potential determining ions 2. Use of stereo-specific collectors 3. Use of flotation rate differences 4. Use of selective activating and depressing compounds. This study was directed toward a cursory evaluation of each of these techniques, and each was found to be a possible method of achieving selectivity. Stereo-specific collectors -- those whose parking area may closely match the available adsorption site on one mineral but not on another -- are a possible means of achieving selectivity between scheelite, fluorite and calcite. Stereo-hindered carboxylic acid salts and sulfonates all show selectivity between the three minerals tested. Separations also appear to be possible by the controlled use of the lattice ions (e.g., Ca and [W0=4] for scheelite, CaW04), H+, [OH-, C0-3 and HCO=3]; all of them ostensibly potential determining in the systems studied. Flotation rate differences of the minerals as a function of pH under conditions of starvation collector usage also showed promise. Scheelite and fluorite float most rapidly with sodium oleate in slightly acidic (pH 4-7) solutions whereas calcite floats most rapidly near pH 10. Use of Mn++, Pb++, or other heavy metal hydroxy complexes as activators was seen to effect each of the slightly soluble minerals differently. This is in sharp contrast to the oxygen containing, relatively insoluble minerals, where all minerals respond in a similar manner to such activation procedures. Results indicate that all four methods outlined above may potentially be used to achieve flotation separation of the slightly soluble minerals. More extensive research should be undertaken to detail the spcific applicability of each of the procedures and to make a more complete evaluation of the effect of collector type and concentration, mineral type, pH and size effects.

Jan 1, 1983

By Alla D. Mah

Relatively pure aluminum nitride (AIN) recently has been prepared in sufficiently large amounts to permit a variety of experimental studies.4/ Several mechanical and chemical properties have been investigated, which show that this substance has good potentialities as a container for liquid aluminum, gallium, and boric oxide. The present work by the Bureau of Mines was undertaken to obtain thermo-dynamic data pertinent to the calculations regarding thermal stability and reactivity of aluminum nitride. The following measurements were made: (1) determination of the heat of formation from the elements at 298.15° K.; (2) determinations of the heat capacity over the temperature range 51° to 298.15° K. and the evaluation of the entropy at 298.15° K. therefrom; and (3) determinations of the heat content over the temperature range 298.15° to 1,800° K. These data are combined to obtain free energies of formation from the elements between 298.15° and 2,000° K.

Jan 1, 1961

By M. L. Glenn

The Bureau of Mines is conducting research on substitutes for chromium-containing alloys in order to conserve imported critical and strategic materials. Part of this research concentrates on finding low-chromium substitutes for heat-resisting stainless steels for the temperature range 600° to 800° C. Ferritic alloys are emphasized that have oxidation resistance provided by chromium contents as low as 10 pct and stress rupture strength provided by the precipitation of the chi(X)-phase intermetallic compound, (Fe36Cr12 (Mo, Ti)10). Initially, research was concentrated on selecting an alloy composition having a minimum chromium content with strengthening provided by the X-phase. An Fe-(10-12 pct)Cr-6 pct Mo-(1.5-2.0 pct)Ti alloy was selected. After the alloy selection, the tensile, stress rupture, and oxidation properties were determined. Stress rupture properties were found to be similar to those of 304 stainless steel. However, the alloys possessed brittleness during both stress rupture and tensile testing, possibly as a result of too high a content of molybdenum and titanium. Higher than expected oxidation rates were found that may be caused by the high molybdenum content.

Jan 1, 1984

By F. B. Petermann

Two-stage electric smelting tests, using small submerged arc furnaces, were made on high-iron manganiferous materials from the Pioche District, Nev., and the Cuyuna Range, Minn. The object was to reduce sufficient iron in the first stage to give a slag with a favorable Mn to Fe ratio for smelting to ferromanganese in the second stage. The nodulized flotation concentrate from the Pioche District contained 29.2 percent Mn and had a Mn to Fe ratio of 2.3:l. When smelted with coke and silica or alumina as flux, more than 90 percent of the manganese was recovered in slags with Mn to Fe ratios of 10: :24:1. The Pioche slag was smelted to ferromanganese using coke and lime- stone or dolomite as flux. The ferromanganese was high in silicon but other- wise met specifications. Recovery of manganese to ferromanganese in this step was 73 to 78 percent. Overall recovery of manganese was about 70 percent. The sintered flotation concentrate from the Cuyuna Range material contained 12.9 percent Mn and had a Mn to Fe ratio of 0.3:1. When smelted with limestone as flux, about 83 percent of the manganese was recovered in a slag with a Mn to Fe ratio of about 6:1. The Cuyuna slag was smelted to ferromanganese with coke and limestone for flux. Recovery in this step was 61 percent of the manganese in a high silicon ferromanganese. Overall recovery of manganese was about 50 percent.

Jan 1, 1963