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By Shigeo Asai

"Electromagnetic processing of materials is newly proposed to be considered as one of the engineering fields where functions of electromagnetism are utilized for processing electrically conducting materials, such as liquid metals, electrolytes and plasmas. The background requiring this processing and the engineering characteristics supporting it are described. The applicable functions of electromagnetism to material processing are revealed from the view point of magnetohydrodynamics. The existing processes and the proposed ones are classified into utilized functions and engineering applications are discussed. IntroductionElectric energy has been used in the metallurgical field for the processes of melting, refining and solidification. In these cases both the magnetic field which is induced by an imposed electric current, and the electric current are applied on electrically conducting materials such as molten metals. Thus, it turns out that the magnetohydrodynamic (MHD) phenomena have unconsciously been seen in metallurgical processes using electric current. The academic backbone studying MHD phenomena is the Magnetohydrodynamics which is being developed in the fields of plasma physics, astrophysics, fusion research and nuclear energy.The first attempt where magnetohydrodynamics was intentionally applied on metallurgy was a Symposium of IUTAM (The International Union of Theoretical and Applied Mechanics) in titled as ""Metallurgical Applications of Magnetohydrodynamics"" at Cambridge, UK, 1982 [1]. This timely event stimulated a few metallurgists to recognize the importance of ~MHD and was a good warning to the metal societies in the world. Especially in Japan, the Steelmaking Investigative Subcommittee of Research Planning Committee in the ISIJ (The Iron and Steel Institute of Japan) discussed the application of ~IHD to metallurgy and selected it as one of the four major innovative subjects for future steelmaking technology in Japan [2]. Indeed, the term of ""Electromagnetic Metallurgy"" itself was firstly coined by this subcommittee. Upon the request of a report from the subcommittee, the ISIJ has established a committee on ""Electromagnetic Metallurgy"" at 1985, under the author's chairmanship."

Jan 1, 1988

By M. M. Ayoub

With a return to coal as a major energy source for many companies, more emphasis is being placed on recovery of coal from areas that were formally considered uneconomical to mine. Increasing emphasis is being placed on production from low coal (seam height 48 inches or less) as high coal seams are depleated. Mining in restrictive spaces requires unusual work postures that can turn easy jobs into demanding ones. The objectives of this research were: (1) to evaluate the job demands associated with low coal mining, (2) to survey the anthropometry, strength, and aerobic capacity of low coal miners to determine if they differ from the U. S. population, and (3) to recommend, on the basis of available information, optimal job and work station design for low coal mining. This research effort was supported by the U. S. Bureau of Mines. The male and female anthropometry with the exception of weight and circumferential dimension, was quite similar to the comparison population. Back strength for male and female miners was significantly lower than the industrial worker population. This can be one of the contributing factors of low back problems in mining. Shoveling, timbering, and helpers tasks were physiologically demanding activities. However, due to the frequent stoppage of work, adequate rest was usually available. If work stoppage is corrected, then better work/rest schedules are essential.

Jan 1, 1981

A compilation of papers presented at the Third WVU Conference on Coal Mine Electrotechnology in Morgantown, West Virginia, on August 4-6, 1976. Papers cover areas of electric power, electronic communications, detection and location of trapped miners, and electronic sensors and monitoring systems.

Jan 1, 1976

By F. W. Wood

ORIGINAL experimentation in specially designed arc-melting furnaces and a comprehensive review of technical literature have helped with an understanding of electric arcs as used in metallurgical applications. Results relevant to the distribution of electric potentials and currents, temperatures, pressures, the consumption of electrodes, the identities of particles participating in electrical conduction, and the modes and mechanisms of discharge are presented and discussed. Present knowledge of high-current arcs is insufficient to test pertinent theoretical suggestions. However, the chief doubts concern the identities and the liberation or formation of current-carrying particles. It seems that either (1) novel formulations of existing concepts are needed, or (2) essentially new concepts must be recognized to explain observations. An analysis of the situation has led the authors to favor the latter possibility and to suggest the existence of supplementary conducting particles. The conduction of current by the streaming of charged agglomerates is postulated. Another outgrowth of analysis is an equation for the arc potential as a function of current densities in the arc. In lieu of conclusions, the potentialities of practical applications and specific needs for fundamental clarification are summarized.

Jan 1, 1965

By H. L. Gilbert

Improvements in production of high-purity chromium metal by magnesium reduction of anhydrous chlorides and by hydrogen treatment of electrolytic chromium are reported. Hydrogen-treated chromium has been arc-melted, and the arc-melted material has been successfully forged, rolled, and swaged. The material also has been forged at liquid-air temperatures. X-ray and metallographic studies indicate the recrystallization temperature of rolled chromium sheet to be about 750° C. Preliminary investigation of hot-bending characteristics of rolled chromium sheet shows the minimum bending temperature to be about 325° C. The heat resistance of chromium has been investigated.

Jan 1, 1952

By R. W. Courtney

The objective of this study is to make a critical evaluation of the magnitude and extent of electrostatic hazards in typical U.S. mining operations and to assess the adequacy of techniques, materials, and equipment for detecting and minimizing these hazards. This was accomplished with an incident/accident survey, mine visits, literature search, and engineering analysis. It was concluded that it would be desirable to (1) utilize ground fault interrupters to minimize stray current from electrical utilities, (2) decrease the current and electrostatic sensitivity of electric detonators used in areas with a high incidence of lightning strikes or troublesome stray currents, (3) institute quality control and test standards for blasting material and protective devices, (4) establish an electrostatic monitoring program for loading ANFO in plastic lined holes, and (5) establish a risk criteria for operator exposure in mines.

Jan 1, 1982

By S. Akhtar

Interstitial compounds of iron, cobalt, and nickel, and their binary and ternary mixtures with silver, gold, palladium, and platinum were prepared and tested as fuel cell catalysts. The first step in the preparation of the interstitial compounds consisted of preparing finely divided metals. This was done either by the Raney method or by reduction of precipitated hydroxides of the metals. The finely divided reduced metals were then treated with carbon-and/or nitrogen-containing gases to prepare their carbides, nitrides, and nitrocarbides. The materials were tested for cathodic activity towards O2 and for anodic activity towards H2, C3H8, NH3, CO, and N2H4 in acid and alkaline electrolytes at 25° to 90° C in half-cell assemblies. Samples of carbided and nitrocarbided INi-lAg-1Au were about one fifth as active as Pt-black in the reduction of O2 in 35 percent KOH solution, whereas the activities of several interstitial preparations exceeded the activity of Pt-black in the reduction of O2 in 12M KOH containing N2H4. Nitrocarbides of x-Fe2C, 3Ni-1Au, and 1Ni-3Au were effective catalysts for oxidizing N2H4 in liquid NH3 containing NH4SCN. Corrosion of the catalysts by electrolytes was severe in many cases.

Jan 1, 1970

By F. B. Samani, B. Stabel

The 1,000 MW Hydro Power Station Masjed-e-Soleiman (formerly called Godar-e-Landar) in Iran is under construction since 1992. The rock engineering aspects of the major underground structure, i.e. the powerhouse cavern shall be reported on in detail. The geotechnical investigations are described and results given. The results of several geotechnical analyses are presented. The designed and executed rock support is given. A description of the monitoring systems and typical measurement results obtained during and after excavation are presented. The lessons learnt during construction of the Stage-I powerhouse cavern were applied on the extension of the powerhouse cavern, which is to house an additional 1000 MW. Details regarding the unexpected behaviour of the Mudstones are given. Die 1000 MW Wasserkraftanlage Masjed-e-Soleiman (vormals Godar-e-Landar genannt) befindet sich seit 1992 in Bau. Dieser Artikel berichtet im Detail über die felsbaulichen Aspekte der Untertagebauwerke, insb. der Maschinenkaverne. Die geotechnischen Untersuchungen werden beschrieben und deren Ergebnisse wie die Ergebnisse verschiedener Berechnungen werden präsentiert. Die geplante und die ausgeführte Felssicherung wird angegeben. Die eingebauten Überwachungseinrichtungen werden beschrieben und typische Ergebnisse während des Aushubs und danach werden dargestellt. Die Erfahrungen beim Aushub der Kaverne der Stufe I wurden beim Entwurf der Kaverne der Erweiterungsstufe II, die weitere 1000 MW beherbergen wird, berücksichtigt. Details zum unerwarteten Verhalten des Schluff-/Tonsteins werden angegeben. La centrale hydroélectrique de Masjed-e-Soleiman (dénommée anciennement Godar-e-Landar), d’une puissance de 1.000 MW, est en construction depuis 1992. Un rapport détaillé sera présenté sur les aspects relatifs à la construction en enrochements de l’aménagement souterrain principal, à savoir la caverne abritant la salle des machines. Une description des investigations géotechniques réalisées y est fournie ainsi que les résultats correspondants. En outre sont présentés les résultats de plusieurs analyses géotechniques. L’ancrage dans la roche tel que projeté et réalisé est présenté. Une description des systèmes de contrôle ainsi que les résultats de mesures typiques obtenus au cours des travaux d’excavation sont donnés. Les leçons tirées lors de la construction de la Phase 1 de la caverne de la salle des machines furent appliquées à l’extension de la caverne de la salle des machines, qui doit abriter une unité supplémentaire d’une puissance de 1.000 MW. Par ailleurs, des détails sont donnés sur le comportement inattendu des argilites.

Jan 1, 2003

By Karl J. C. Harries

"10.1. INTRODUCTIONDefinitions are a necessary part of every agreement. Their purposes are to assist the reader in reading and understanding an agreement and to attempt to avert potential confusion and, therefore, disputes. In some circumstances, they may be critical in deciding a dispute. As they are often substantive, they should not be treated lightly.It is far easier and less confusing for a reader to read “the Company” or “the Recipient” than to be faced with “the party of the First Part”, or to see the “Jones Property” than “that part of the property hereinbefore described in paragraph 1.01 hereof”. It is also advisable not to use “-ee” and “- or”, as in payee and payor.One thing must always be remembered: once a word has been defined in an agreement, it will always have the defined meaning unless the contrary is clearly indicated or is required to make sense of a provision.2 It can be confusing for a reader if commonly used words are defined in other than ordinary terms. Unique words that will stand out in the text are more likely to be recognized as having special meaning. It is also good practice to identify defined terms by capitalizing them in the text of the agreement. Boldfacing of definitions is also sometimes used for this purpose but, as boldfacing is not easily identified in handwritten revisions, it can be missed in the press of negotiations, especially when several typists are involved. Lack of consistency in identifying defined terms is not a fatal mistake, but it can create confusion, especially if the reader is new to the agreement or is reading it in a highly technical manner, such as when there is a dispute.If definitions used in the main text also apply to a schedule, they need not be included in both. Omitting them from the schedule makes the agreement look shorter, which to some people is a benefit. If definitions are not repeated, make certain that the schedule clearly indicates that words defined in the main text have the same defined meanings in the schedule3 and are clearly identified as defined words. In considering whether or not to repeat in a royalty schedule definitions appearing in the agreement proper, think of definitions as an aid and a reminder to the reader. Repeating them will help a reader, if only by saving the nuisance of remembering where to find them in the main text and constantly turning to it. All the definitions needed to read the schedule will be right there, so that the schedule is a self-contained document. Just make certain that, if you do repeat a definition, you repeat it in identical terms. If you have to change any defined term to make it fit the royalty provisions, use a different word or phrase as the defined term to warn the reader that he is dealing with a different concept.4"

Jan 1, 2003

During the extensive research which has been conducted in the Metallurgy Department of the University of Melbourne, into the properties of lead and its dilute alloys, the Brinell test has been used for the determination of hardness.The work described herein represents part of an investigation into the influence of various factors on such determinations, particularly when carried out on different qualities of "pure" lead. It is intended to publish the more theoretical and controversial aspects of this research elsewhere.MATERIALS USED AND THEIR PREPARATION FOR TESTINGThe tests to be reported have been conducted on a specially pure electrolytic lead, and several brands of commercially "pure" lead. The analyses of the samples upon which most of the work has been carried out are given in Table 1.Note: Oxygen was not determined, but from the work of H. W. Worner, in the Rosenhain Memorial Laboratory, it appears probable that it was approximately 0-0003% in all samples.

Jan 1, 1940

By B. K. Gorain

"As mining has evolved over a century, so are the challenges associated with mining. Mining of complex ore bodies at greater depths is a major challenge requiring high capital and operating costs due to remote locations, high energy costs, water quality and complex environmental issues. In addition, the stakeholder expectations are growing along with challenges associated with highly complex mine permitting processes and changing demographics of mining jurisdictions. The dynamic metals market adds to these challenges impacting the long term development and sustainability of mining projects.These challenges are compelling mining companies to look at various innovations with an integrated approach focusing on meeting the needs of various stakeholders. Mining companies are slowly tapping into some successful concepts that have transformed other industries such as manufacturing, chemical, pharmaceuticals along with oil and gas.This paper provides an overview of various innovations and technology developments in mineral processing that have shaped the current mining industry. A glimpse of the present and future challenges in mining is also presented. An integrated approach to problem solving involving various stakeholders is gaining momentum and this has been reflected in this paper. Various developments that are being pursed in mineral processing focusing on a change in the existing mining paradigm are also presented in this paper.INTRODUCTIONAs mining is evolving, so are the challenges associated with mining. Some of the key challenges are complex ore bodies at greater depths, high capital and operating costs, water scarcity and quality issues, high energy costs, complex environmental issues including tailings management, worldwide constraints on resource availability, more and more elaborated regulations in emerging economies impacting the permitting processes, increasing stakeholder expectations, changing demographics of mining operations with ever-changing cultural or community expectations and the urgent need for a better assessment of project viability, this in very dynamic metals markets impacting the dynamics of mining projects development and sustainability."

Jan 1, 2016

By J. E. Terry

This paper outlines the steps that are being taken to close the gap between training and industry and indicates areas in which more work needs to be done. Although based on experience in the Maritime Provinces, it is applicable to industrial and educational studies across the length and breadth of Canada.

Jan 1, 1970

By Mark S. Sanders

The present study was designed to explore the contribution of organizational climate and management practices to the injury experience in underground coal mines. A cross-lagged panel design was used in which miners from 22 mines completed questionnaires assessing 27 organizational climate, structure, and function dimensions on two occasions, The results strongly support the hypothesis that climate and management practice have casual effect on the incidence of disabling injuries.

Jan 1, 1976

By E. P. Ferrero

Analyses of 38 crude oil samples from 25 fields in Algeria, Libya, and Nigeria are presented in this report. The 38 crude oils are listed alphabetically by country and field. Also shown are the geographic and geologic sources of the samples analyzed, the companies that supplied the samples, the general characteristics and analytical and computed data, and the production for the fields from which the samples were obtained.

Jan 1, 1966

By E. P. Ferrero

Analyses of 38 crude oil samples from 25 fields in Algeria, Libya, and Nigeria are presented in this report. The 38 crude oils are listed alphabetically by country and field. Also shown are the geographic and geologic sources of the samples analyzed, the companies that supplied the samples, the general characteristics and analytical and computed data, and the production for the fields from which the samples were obtained.

Jan 1, 1966

Helium has probably aroused more varied scientific curiosity than any other single element. Discovered by spectroscopic examination of the sun during an eclipse in 1868, helium is now known to exist not only in the sun and other stars but on earth occluded in minerals, accumulated with natural gases in pockets in the earth's crust, and in the atmosphere surrounding the earth. Astronomers study its presence in the various stars of the universe for clues to their origin and history. Geochemists and geologists study its occurrences in rocks, minerals, and meteorites to determine the age of the earth and the manner of its formation. Pathologists study its effect on living tissues in search for the ideal combination with oxygen for artificial breathing mixtures in medicine, diving operations, and space vehicles. Chemists study its physical properties and use it to trace the sequence of events in reactions in which it does not participate. Geneticists and bacteriologists use it for special studies. Physicists study its behavior when liquefied and the behavior of materials cooled to nearly absolute zero by its use. Nuclear physicists learn more about the universe through study of the nuclear reactions that produce it. Through study of helium and greater knowledge of its origin and properties, science continues to unlock some of nature's more closely guarded secrets. Unknown on earth before 1895, and not discovered as a minor constituent of natural gas until 1905, helium with its simple atomic structure--a nucleus with two electrons orbiting in a closed shell--is a unique element. It is next to the lightest gas, only hydrogen is lighter. It occupies position number 2 in the Periodic Table of the Elements and heads the list of so-called "rare" or ?noble? gases. Most of the naturally occurring helium has an atomic mass of 4.003874 (oxygen = 16). A trace (1.7 x 10-5 mol percent) is the light isotope helium-3 whose atomic mass is 3.0169800 Unstable isotopes of mass numbers 5 and 6 have been authenticated. Isotopes of mass numbers 7 and 8 have been reported, but their existence is less well established. All the heavier isotopes are radioactive and are the product of nuclear reactions.

Jan 1, 1968

"Editor’s note: Each year, Mining Engineering features an industrial minerals review. Several people put in a fair amount of time in developing the material for this issue, all the while doing their own jobs. Thank you to the industrial minerals annual review editor, to the Industrial Minerals and Aggregates Division technical committee chair and vice chairs, and to the authors of the individual commodity profiles.Jim Norman, member SME, of Tetra Tech, is the industrial minerals annual review editor.Vishal Gupta, member SME, of EP Minerals LLC, is chair of the Industrial Minerals &Aggregates Division’s Technical Committee.The technical committee vice chairs include:• Vishal Gupta, member SME, of EP Minerals LLC, Agricultural Materials.• Joe Garska, member SME, of Imerys, ceramics and refractory materials.• Stanley Krukowski, member SME, of the Oklahoma Geological Survey, chemical raw materials.• Russell Winn, member SME, of R.E. Janes Gravel Co., chemical raw materials.• Justin Zdunczyk, member SME, of Pike Industries, construction aggregates.• Jerry Gauntt, member SME, of Golder Associates, fillers and pigments.• Ebrhaim K. Tarshizi, member SME, of the Michigan Tech, sorbents, filters and process aids.• Daniel T. Eyde, member SME, of St. Cloud Mining, specialty minerals.Their help makes possible this July industrial minerals issue. On behalf of ME readers, the editors thank them.Virta, R.L. U.S. Geological Survey, National Minerals Information CenterFour companies - H.C. Spinks Clay Co., Inc., Imerys, Old Hickory Clay Co., and Unimin Corp. - mined ball clay in four states in 2013. On the basis of preliminary data, production was 1 Mt (1.1 million st) with an estimated value of $47 million. Production increased by 3 percent in tonnage from 973 kt (1.1 million st) with a value of $45.1 million in 2012. Tennessee was the leading producer state accounting for 64 percent of domestic production, followed by Texas, Mississippi and Kentucky. About 67 percent of total ball clay production was airfloat, 22 percent was crude or shredded and 11 percent was water-slurried.ConsumptionIn 2013, domestic ball clay producers sold clays to the following markets: ceramic floor and wall tile (44 percent); exports (21 percent); sanitaryware (18 percent); miscellaneous ceramics (9 percent); fillers, extenders, and binders, and unspecified uses (4 percent each), based on 2012 end use patterns and current markets. Other markets accounted for less than 1 percent of the remaining ball clay sales or use. Sales reported for the manufacture of fiberglass or most filler, extender, and binder applications were likely to have been mainly kaolin mined or purchased by the ball clay producers.PricesThe average value of domestically produced ball clay was approximately $47/t ($43/st) in 2013 compared with $46/t ($42/st) in 2012, on the basis of a preliminary survey of domestic ball clay producers. The unit values of exported and imported ball clay were $126/t ($114/ st) and $373/t ($338/st), respectively, in 2013, compared with $62/t ($56/st) and $314/t ($285/st), respectively, in 2012. Unit values for most large export shipments increased in 2013, and a larger number of low-tonnage, high-value export shipments were shipped in 2013 than in 2012, resulting in a doubling of the average export value. Two low-tonnage, high-value shipments in 2013 accounted for the increased value of imports."

Jan 1, 2014

By R. S. Dean

[During t!~c past f isc.~l y~:-.r the Xetzllvz-gicd 3ivi oion has made im- portant contribution-, don,- tlie lines rlictnteil by the Bureau policy of con- servation of domestic rnker~l rcsoul-ces throui;h use. During t!~c past f isc.~l y~:-.r the Xetzllvz-gicd 3ivi oion has made im- portant contribution-, don,- tlie lines rlictnteil by the Bureau policy of con- servation of domestic rnker~l rcsoul-ces throui;h use.]

Jan 1, 1940

The wealth of a nation may be measured in many ways, but one of the most important is its natural resources, particularly its minerals. Minerals create the wealth upon which economic prosperity and defense preparedness rest. Managing mineral resources for the benefit of all Americans continues to be an important national goal. In its 78-year history the U.S. Bureau of Mines has established itself as the world's premier mineral information and research agency. Its authoritative, comprehensive data and pioneering research have contributed significantly to a strong U. S. mineral position in the world.

Jan 1, 1988

By AIME AIME

THE 123d meeting of the Institute was held in New York Feb. 14 to 17, 1921. The total registration was 1199, as compared with 1138 at the New York meeting in 1920. The weather was a strange and welcome contrast to that of last year, when New York was buried under six feet of snow as the result of the fiercest blizzard in its history. This year there was no snow, and the weather was said to be much more like an Arizona winter than New York. A complete program of the Technical Sessions is on p. 9. The discussions of the papers presented will be published in pamphlet form as soon as possible and will be noted in MINING AND METALLURGY in the usual way.

Jan 1, 1921