Search Documents

By S. Yamaguchi

IN this study of thorium and uranium minerals an x-ray shadow microscope of the Cosslett type1 was used. A flux of electrons driven with a voltage

Jan 1, 1959

By J. B. Patton

No academic program of reasonable duration can provide a geologist with all the skills that may be needed for applied work in industrial minerals. However, any curriculum that does not provide background in such basis subdisciplines as mineralogy-petrology, stratigraphy, sedimentology, structure, and geomorphology will leave the practitioner handicapped. Enough geochemistry to understand materials requirements, and sufficient geophysics to use geophysical data, are essential. In addition to purely scientific considerations, the industrial minerals geologist must be able to evaluate economic factors. He may also be faced with legal, social, and political problems in land use, zoning, envil.onmenta1 protection, and reclamation.

Jan 1, 1985

By W. A. Goodyear

It is safe to assert that in cities generally, the fuel of the future for all domestic, as well as for most manufacturing and metallurgical purposes, will be gaseous fuel. The immense advantages which gas possesses in facility and cheapness of distribution, cleanliness, and economy of manipulation, and the facilities which it offers for utilizing in almost all cases a much higher percentage of the total quantity of heat produced, than it is possible to do with any kind of solid fuel, are facts which will vastly more than compensate for the comparatively small loss of heating power, which will be found necessary in the turning of the solid fuel into gas upon a large scale, and which, in the bpinion of the writer, will, at no distant day, command attention, and will ultimately result in a revolution in our use of fuel. The employment of gaseous fuel upon a scale of any considerable magnitude, has hitherto been almost entirely confined to the utilization of the waste gases of the iron smelting furnace for heating the blast, and the rapidly increasing use, for certain metallurgical pur-

Jan 1, 1883

Frank Firmstone, Easton, Pa. (communication to tlie Secretary*) :—Mr. Dilworth's formulas hnd tables are of course correct, and the extillction will occur as calculated, provided the nioney periodically set aside for sinking-fund be really invested and the interest compounded as assumed in the calculation. Actually, in alrilost all cases, such funds are used " in the business," in which case, in addition to the periodical charges for principal of the fund, additional charges must he made at the end of each period to cover the interest and compound interest on previous charges. The periodical charge for sinking-fund thus becomes a varyillg and continually increasing one until the date of extinction. On many accounts it scems more natural and conveniellt to make the extinction by a fixed periodical charge under the legal rule for partial payments,

Jan 1, 1911

By Victor Phillips, J. P. Blair

Jan 1, 1952

PENNSYLVANIA ANTHRACITE SECTION Executive Committee R. V. NORRIS, Chairman. CHARLES F. HUBER, Vice-Chairman, W. J. RICHARDS, Vice-Chairman, EDWIN LUDLOW, Vice-Chairman, ARTHUR H. STORRS, Vice-Chairman. CHARLES ENZIAN, Secretary-Treasurer, U. S. Bureau of Mines, Wilkes-Barre, Pa. DOUGLAS BUNTING, FRANK A. HILL, ALBERT B. JESSUP, RUFUS J. FOSTER, JOHN M. HUMPHREY, ROBERT A. QUIN. The Pennsylvania Anthracite Section held its second regular meeting at the Pottsville Club House, Pottsville, Pa., July 25,1914. The meeting was attended by more than 90 members and guests. Vice-Chairman W. J. Richards presided. Following an informal dinner, W. G. Whildin, Mining Superintendent, Lehigh Coal & Navigation Co., Lansford, Pa., presented a. paper on Steep Pitch Mining of Thick Coal Seams, illustrated by numerous drawings. This paper will be printed in the November number of the Bulletin. A lively discussion followed the reading of the paper.

Jan 10, 1914

By S. H. Shepard

During the past year, a number of significant events have occurred in the nuclear industry. These include a surge in nuclear power plant orders, delays in nu- clear plant licensing and construction, increased environmental concern and the new Atomic Energy Commission nuclear fuel policy. These events, particularly the AEC stockpile release policy, have lead us to take this opportunity to update National Nuclear Corp.'s (NNC) appraisal of the outlook for the U.S. uranium industry.

Jan 10, 1972

By Mark W. Springett

The sampling of precious metal deposits entails inherent problems due to the low mineral abundances, high mineral specific gravities, skewed grade distributions and wide ranges of mineral particle sizes. Sampling practices and precautions are discussed with particular attention to each of the tripartite stages of sampling - sample acquisition, sample preparation and sample assaying. Practical examples of approaches to the sampling problem are given and some examples of significant sources of error are provided from gold and silver deposits in North America.

Jan 1, 1984

By Ch. J. Raub

A review will be given on the electrodeposition of Au, Ag and Pd and their technically important alloys focusing on recent work at the Forschungsinstitut. Special emphasis will be given to the influence of impurities on the behaviour of the electrolyte and the properties of the deposits, e.g. on resistance and on thermal and mechanical behaviour. The importance of C in gold and silver deposits and of H2 in Pd and its alloys at normal and high speed deposition rates will be discussed. Among Pd alloys attention will be focused on the Pd-Ni and Pd-Ni-Co systems. Comments will be made on deposition of Rh and Pt.

Jan 1, 1984

By R. W. Smith, R. J. Charles

Fractions of glass particles in the size range 0.5 to 5.0 µ were prepared by an elutriator that operates in a centrifugal field. Although mean sizes of commercially graded abrasive powders were ten times greater than those of samples prepared by the elutriator, frequency size plots for elutriator samples compared favorably. Efficiency of separation was low and amounts of material recovered by the elutriator were small, but the method should find use in preparation of small amounts of sized materials for laboratory investigations.

Aug 1, 1956

By W. L. Price

Since they were first introduced in the United States in 1964, rail mounted bucket wheel stacker-reclaimers have gained wide acceptance by the coal burning power plant group. Other installations include those in phosphate and steel mill ore storage areas. First Installation in the U.S.A. Three basic types of bucketwheels for handling stored bulk materials are now being used in the U.S. Bucketwheel stacker-reclaimers came into use in the U.S.A. in 1964 at the Chalk Point power station built by the Potomac Electric Power Co. It was decided, after serious study, to install the first slewing-boom, rail mounted bucketwheel stacker-reclaimer at this installation. It was designed with a separately counter- weighted wheel boom because the fixed counterweight of the European designed bucketwheel made it possible for the machine to overturn backwards if the wheel rested on the ground due to a possible failure of the luffing system.

Jan 1, 1970

By Öner Yücel, M. Zeki Dogan, A. Metin Ger

Technical and financial feasibility studies conducted at the Middle East Technical University, in Ankara, Turkey, have revealed that a 400 km long prospective slurry pipeline between Hasançelebi and Iskenderun could efficiently and economically transport iron concentrates, with a size of 55%-325 mesh and of amounts varying between 0.25 and 8.0 million tonslyear. Particularly for annual throughputs above 500,000 tons, favorable results have been obtained regarding the processing of the ore, the applicability, the transport cost, and the foreign ex- change currency savings.

Jan 1, 1980

By Joseph L. Mehaffey

A variety of chemicals offered by Armak were evaluated as dewatering aids for aqueous slurries of silica sand, sparsand and feldspar; an established commercial dewatering aid was used as a control. A number of Armak’s potential dewatering aids yielded lower moisture retention values than did the commercial product on all of the mineral samples. In addition to the chemical dewatering evaluations, some of the mechanisms involved in the removal of water from these mineral samples were examined.

Jan 1, 1984

By Charles J. Speake, Dennis R. Haley, Thomas E. Finch

As there exists a strong trend to computer assisted mine design, this twofold presentation will emphasize an examination of the parameters wed to create a mine design computer program. The program results are a first-order engineering design and evaluation of methods wed to handle the parting or inner burden found in thick-seam western surface coal mines. The alternative selections are draglines, backhoes, scrapers, front-end loaders, shovels, and bucket wheel excavators used in direct stow or haul-back techniques. The computer program wed in the design selection will be explained and typical input and output information shown.

Jan 1, 1980

By William C. Waldbieser

Webster's Third New International Dictionary defines new in part as "having been seen or known but for a short time although perhaps existing before." It has recently become fashionable to talk about the new life for old "King Coal," and how we will have to double or even triple our coal production by 1985, or how the US will become energy-independent by 1980. Since coal represents over 80% of our proven energy reserve, the nation will turn to coal as a savior in our time of energy crisis, so goes the argument.

Jan 10, 1974

By Thomas L. Kesler

Lithium raw materials usable with present technology consist of pegmatite ore and shallow evaporite brine. Deposits of these materials occur in many parts of the world. Those advantageously located supply the present lithium industry. Less favorably located deposits will come into production as markets expand and present sources are depleted. In this discussion, materials listed as reserves include fully explored and partly explored deposits. For those closely drilled and assayed, the data provide measurements rather than estimates, and such reserve tonnages are "proved." For deposits partly explored, the data support reserve estimates of "probable" tonnages. Materials lacking exploratory data are classed as resources, and their "possible" tonnages are inferred mostly from indirect evidence and are essentially objectives for exploration. All figures for pegmatite ore apply to total materials in the ground.

Jan 1, 1979

By R. J. Wasilewski

OBSERVATIONS have been made that the substitution of antimony for bismuth in Bi2Te3 leads to anomalies in some of the electrical and magnetic properties of the Bi2Te3-5S2TeS alloy system at the composition ratios 2 Bi2Te3 : 1 Sb2Tes and 1 Bi2Te3 : 2 Sb2Te3. Airapetiants and Efimova1 have reported the peaking of the nondegenerate hole mobilities, at these compositions for sintered materials and ascribe the peaking to the formation of ordered alloys. From a study of these materials produced by the Bridgeman

Jan 1, 1962

By G. E. Kedzie

The ore-deposits of ail that portion of the San Juan country within the borders of Ouray County are either in the tertiary ernptives or, confined to a relatively narrow zone, in the sedimentary beds just beneath them. The ore-deposits in the igneous formation

Jan 1, 1888

By H. Xi-Lum

Three rapid cold bonding production methods wing sponge iron powder as a binder for low temperature pellets have been successfully developed. These methods differ from ordinary bonding by the elimination of salt and other catalyzers, equipment corrosion and environmental pollution. Experiments show that these pellets have good metallurgical properties. A semi-industrial test has proven the laboratory results, with the continuous and stable production of metallic pellets. These methods replace traditional high temperature firing of oxidized pellets for direct reduction. As a result, the plant for oxidized pellets can be saved and substituted for grate in the grate-kiln system. Thus, 20% of the investment could be saved, and production cost may also be decreased because the production of cold bonding pellets does not need additional space.

Jan 1, 1984

By P. R. Sheorey

Understanding of in situ rock mass behaviour has taken a step forward with the advent of the refined rock mass classifications of Wickham, Bieniawski and Barton et al. In this paper six case studies are given in brief showing how Barton's classification could be used in mining situations. The cases cover stability of roadway junctions under shallow covers, support pressure estimation in roadways in intact and failed rock conditions, determination of the safe unsupported span of a wide stope and estimating the stability of roadways in two contiguous seams standing 011 small pillars against puncture of the parting rock.

Jan 1, 1983