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By Michael Hoch, Michel Desjardins

The isothermal section of the Mo-Ti-Zr-0 system at 1500°C was investigated using X- ray diffraction and mefallographic techniques. Up to 66.7 at. pct 0, the system contains ten four -phase regions. Isopleths at 10, 30, 45, 55, and 60 at. pct 0 were constructed. THE purpose of this investigation was to determine the general shape of the quaternary equilibrium phase diagram of molybdenum, titanium, zirconium, and oxygen at 1500°C. The system was truncated at 66.7 at. pct o. PREVIOUS INVESTIGATIONS The Ti-Zr-0 system was investigated in this laboratory.' The binary systems of interest have been compiled and discussed by Hansen' and Levin, McMurdie, and Hall.3 Farrar, Stone, and Margolin studied the titanium-rich corner of the Ti-Mo-0 ternary. MATERIALS The titanium powder, 99.6 pct pure, the zirconium dioxide, and the molybdenum powder were supplied by the Fairmont Chemical Co. The zirconium powder,

Jan 1, 1962

By Nicholas J. Grant, Olaf Troili, John Chipman

D. C. Hilty (Union Carbide & Carbon Research Laboratories, Niagara Falls, N. Y.)—How does this effect of silica compare with the effect of silica in combining with the lime in the slag to reduce the activity of CaO, thereby affecting the first equation? John Chipman(authors' reply)-—That is the object of showing this effect for slags of two different basicities. In the more basic, the silica is more firmly tied up in the slag and is less easily reduced. It is therefore less able to interfere with desulphurization. The important point is that silica is acting in two ways. Of course it is an acid and as an acid it ties up lime and in tying

Jan 1, 1952

ON FEBRUARY 13, 1953 the Miami Copper Company signed a contract with the United States Government, through the Defense Materials Procurement Agency, whereby it under- took, with a base price of 27.359 per lb (subject to escalation based on wage scales and wholesale-price indices), to exploit a new ore body in its mine in Gila County, Arizona. Recoverable ore was estimated at 23,000,000 tons, averaging about 0.677 per cent copper. Moreover, the proportion of oxidized copper, difficult to recover by flotation concentrating, was so high that an average net recovery of only ten pounds per ton (0.5 per cent) was expected. The company proposed to mine the ore by the underground method known as undercut block-caving. Unfortunately the ore body, as has been true of all Miami's ore bodies, lay so deeply buried that no possibility existed of adopting opencut mining as has been done in recent years at Miami's neighbors, Ray and Inspiration. Probably the most distinctive characteristic of Miami's operations has been the extent to which it has developed and improved methods and equipment for underground mining. True, necessity was a potent stimulant, because its available ores since 1926 have been exceptionally low-grade; so, if the enterprise were to survive, it was necessary to keep costs at the minimum. This fact does not detract, however, in any way from the remarkable achievements of Miami engineers in conducting efficient and low-cost underground mining.

Jan 1, 1957

By Earl Bardwell

(Butte Meeting, August, 1913.) THE structural relations existing between cuprous oxide and copper were first systematically studied by Heyn1, who suggested that a study of the microstructure of refined copper might be substituted for the analytical methods in vogue for determining the oxygen content of copper coming .;from the refining furnace. Hofman, Green and Yerxa,2 in their paper A Laboratory Study of the Stages in the Refining of Copper, working along the lines suggested by Heyn, showed that a study off the microstructure could be made to yield a correct estimate of the oxygen content of the specimen of refined copper under examination. In order to determine the oxygen content of the specimen of refined copper under examination a photomicrograph was first made. From the relative areas of copper and eutectic, the percentage of cuprous oxide and the corresponding percentage of oxygen were then readily calculated. It was found that the values for oxygen thus obtained corresponded closely with the analytical results. With the idea of utilizing, this method of determining the oxygen content of each charge dipped from the refining furnaces at the Boston & Montana Reduction Plant, the physical testing laboratory was equipped with suitable apparatus for carrying out the work. It may be of interest to describe certain of the methods which have been worked out in, this connection and give such data as have been obtained bearing on the effect of the oxygen content of refined copper upon its conductivity.

Jan 7, 1913

By W. J. McGee

Most nations and states have conducted geological surveys, generally with the view of discovering and developing natural resources, sometimes with the aim of promoting science. In some cases, as in the first survey of Pennsylvania, the official geologist so far preceded the prospector and miner as to guide the discovery and exploitation of the commoner ores, mineral fuels and structural materials; but in most instances statesmen have only been awakened to the need of such a survey by the successful extraction of minerals;

Jan 1, 1893

New York, March 18, 1913. MR. CHARLES F. RA ND, President, New YORK, MARCH American Institute of Mining Engineers. Dear Sir: In connection with the official notice of Dr. Raymond's unanimous election by the Directors as Secretary Emeritus, we wish to place upon record certain statements concerning his services to the Institute which we think have not been published., and may not be generally known to the majority of our fellow-members. When the Institute was formed in 1871, Dr. Raymond acted as Secretary of the Founders' Meeting, and became the first Vice-President of the Institute, and, by request of the aged and beloved David Thomas, who was the first President of the Institute, Dr. Raymond discharged all the duties of the office of President, to which he was later formally elected in 1872, and which lip held for three years. During that time, he visited Europe, and through his acquaintance and reputation abroad, established those international relations of the Institute which proved so important in later years. He also enlisted the support of the mining engineers and metallurgists of the Pacific Slope, who would not otherwise have been disposed to join a society originating in the East. And for twelve years he attended; at his own expense, nearly every meeting of the Institute, wherever held, giving to it without remuneration his best service, and sacrificing for it many professional and private interests.

Jan 4, 1913

By C. A. Mezger

These districts are limited approximately on the north by the railroad from Salisbury to Ashville, and comprises the counties of Alexander, Catawba, Burke, Rutherford, McDowell, Cleveland, Lincoln, Polk and Henderson in North Carolina, and Greenville, Spartanburg, Union and York in South Carolina. The occurrence of monazite at Amelia Court House, in Virginia, belongs evidently to the same geological system, as its distance from the Alleghenies corresponds with that of the above-mentioned districts, and all the stratification runs parallel with those mountains.

Jan 1, 1896

By J. W. Still

CIRCULAR steel sets have proved to be more economical for supporting slusher drifts in the block-caving mining used by the Miami Copper Co., at Miami, Ariz. The first steel sets were installed in July 1950, and up to July 1, 1951, about 474 sets (approximately 1896 ft of drift) were placed; the bulk of this work was done in the latter six months. All of the places selected for the steel were in heavy ground. Based on this experience the following definite conclusions can be drawn:

Jan 11, 1951

By John J. Van den Broek

As the established tailings disposal techniques do not meet the requirements of today, alternative methods of disposal are explored. McIntyre Mines Ltd., Coal Div. found a solution in the construction and operation of a tailings dewatering plant. The solids are recovered from the tailings slurry by means of mechanical dewatering equipment and are then dried in a unique drying system to provide an excellent thermal fuel for a power generating station.

Jan 1, 1983

By A. N. Holden, J. H. Hollomon

A. H. COTTRELL* and A. T. * Dept. of Metallurgy, Birmingham Univ., England. CHURCHMAN*—We have been making some experiments recently very similar to those reported by Messrs. Holden and Holloman. Wires of Armco iron, 0.077 in. diam. were decarburized in wet hydrogen until the yield point was removed; they were then extended 31/4 pct and annealed at 880°C for 120 hr in dry hydrogen. This process produced large crystals which extended through the cross-section and were about 3/4 in. in length. Since the length of each crystal

Jan 1, 1950

The Mining Engineering Society of the State College of Washington, Pullman, Wash., has elected the following officers for this semester: F. MASON, President, WILLIAM WHITE, Vice-President,. L. E. TRAEGER, Secretary and Treasurer. The Society holds meetings every two weeks at which papers on mining and metallurgical topics are presented by students and members, of the faculty. At the meeting of Oct. 25, Prof. H. R. Robbins gave an interesting talk upon the Rankin Process for the treatment of base-metal ores. In this process the metals are extracted by the use of nitric acid, the acid -being recovered almost entirely. Prof. Robbins thinks the process has great possibilities, but it has not yet been worked on a commercial scale. The Missouri Mining Association, the student organization at the Missouri School of Mines, Rolla, Mo., has. elected the following officers for the ensuing year: L. W. EHLERS, President, H. A. KLUGE, Treasurer, J. G. REILLY, Vice-President, N. E. RITTER, Secretary.

Jan 12, 1915

Charles Catlett, Staunton, Va. (communication to the Secretary*):—Mr. Chance's suggestions that the brown hematite-ores of the Potsdam formation are due to the alteration in place of iron sulphide, and that their extension may reasonably he expected to contain valuable deposits of unaltered sulphide, are interesting; hut the facts marshaled by him are too limited

Jan 1, 1909

By Bashir Ahmed, Fred D. Wright

Numerous investigators have studied the various factors that influence the ultimate strength of model mine pillars, such as ratio of height-to-least width; restraint or friction on the top and bottom; 1,2 the effect of stress distribution in pillars on their strength;3 and the scaling factors involved in applying the results of model pillars to full-scale pillars. However, the load-bearing capacity of pillars after initial failure does not appear to have been investigated. Yet many mines employ methods in which small pillars or pillar remnants are left systematically; these pillars crush as mining progresses and, of necessity, affect the behavior of surrounding rock even after initial failure. The effect of such crushed or crushing pillars depends largely on their load-deformation characteristics. This chapter presents the results of a preliminary investigation to determine the load-deformation characteristics of a few model mine pillars to and beyond initial failure. Various investigators have also studied the elastic and viscoelastic behavior of mine structures. In such studies, computers are frequently employed to obtain numerical results by the finite difference or finite element methods. It would be entirely feasible to write a program that would approximate the load-deformation characteristics of pillars to and beyond the crushing stage if these characteristics were known. More accurate information on the induced stresses and deformations in overlying strata and on surface subsidence could be obtained, information which should result in better strata control by enabling the engineer to calculate more accurately the effects of changes in pillar spacing, size, and shape.

Jan 1, 1972

By Vincent Gianella

Barite deposits are of widespread occurrence in Nevada but there are few pro-ducing properties; most of the latter are in northern Nevada. The production of the state is small at present-in the neighborhood of 15,000 tons annually-but is steadily increasing. The barite occurs in veins and also as replacement deposits in lime-stone. The bulk of the production has come from the replacement deposits. It is thought that the barite was deposited from rising hot waters similar to-and probably contemporaneous with-those responsible for some of the metallic ores of the state. This paper discusses only the deposits in northern Nevada. THE commercial mining of barite did not begin in Nevada until 1916 but although the production has been small there has been a rapid increase in tonnage during the past several years. Barite is widely distributed in the state and production comes from at least nine of the seventeen counties. Apparently this is not generally known, as only two counties are mentioned in a recent publications dealing with barite. The increase in output is due largely to recently discovered barite deposits in northern Nevada. The principal production has come from the northern portions of Lander and Eureka counties; smaller amounts from Elko County. The discussion in this paper is confined largely to the deposits in these counties. Most of the producing area is tributary to the Western Pacific and Southern Pacific Railroads, whose tracks lie along the Humboldt River. Barite is known from other northern counties but so far the production has been small. The output has come entirely from veins and replacement deposits, the latter largely in sedimentary rocks. In general, the barite from veins is white; that from the replacement deposits usually is dark gray to black, although some is light gray or white. Most of the veins contain sulphides and many barite-bearing veins have been worked for their content of base or precious metals.

Jan 1, 1940

On June 15, Dr. E. E. Southard gave the following report to the Advisory Committee on Industrial Mental Hygiene of the. Engineering Foundation. Psychiatric social work, a new specialty in social work, was the topic of several section meetings (500-600 in attendance) at the National Conference for Social Work, held at Atlantic City, June 1-6. The new specialty was stated, by Dr. R. C. Cabot, to be the greatest single advance in medical social work since its establishment. Reports from three schools (Smith, New York, Philadelphia) indicate a good production rate of personnel, probably at least one hundred a; year, chiefly to be absorbed by hospitals, unless industrial psychiatry steps into the field. No detailed public announcements concerning industrial psychiatry were made; but private discussions elicited approval only for the program. Indications are that many non-medical social workers will decide to get additional training to go into medical social work and then to specialize in psychiatric social work and that many medical social workers will desire to specialize in psychiatric social work, with a view partly to entering reconstruction work, partly to entering industrial psychiatry. Suggestion has been made that psychiatric social workers may go into some kinds of, employment management and may look for special courses to that end. Evidence. has been brought that certain "compensated" psychopathic employees have been good (even very good) workmen: emphasis should be laid on this point to show the constructive aspect of industrial psychiatry:

Jan 8, 1919

By David M. Hopstock, Jose M. Pastrana

The magnetic susceptibilities of samples of natural and artificial hematite and natural goethite were measured by the Faraday method as functions of temperature, magnetizing field strength and particle size. All samples showed weak ferromagnetism, which accounted for large variations in susceptibility with field strength and particle size. Three probable sources of the weak ferromagnetism were identified.

Jan 1, 1978

By Paul T. Allsman, E. W. Newman

TRENCHING, sampling, and core drilling in Stillwater and Sweetgrass Counties, Mont., by the Bureau of Mines have delimited over 5,000,000 tons of chromite ore containing more than 20 per cent chromic oxide. The Benbow and Mouat-Sampson mines have been developed and are fully equipped for mining and milling 500 tons and 2000 tons a day, respectively.

Jan 1, 1944

By H. A. Wheeler

The great depths attained by some of the older mines, and the milch greater depth at which they will have to he worked in the not distant future, strongly emphasize the imperfect and inadequate character of our present hoisting-practice. The depth of 3000 feet having been exceeded at several places, and 4000 feet almost reached

Jan 1, 1891

The largest variety of asphalt and related bitumen deposits in this country is found in Utah. Utah is one of the few places in the world where the hydrocarbon minerals, gilsonite or uintaite, wurtzilite (trade name elaterite) and ozokerite are produced. These bitumens occur in an area embracing nearly 10.000 square miles in eastern Utah near the Colorado line. This area is largely in the western part of the Uintah basin. The bitumens are in the Tertiary horizon in the various divisions of the Eocene series. Cilsonite is an asphaltite derived from petroleum, wurtzilite is an asphaltic pyrobitumen derived from petroleum, and ozokerite is a native mineral wax resulting from the metamorphosis of paraffinaceous petroleum.

Jan 1, 1925

A bibliography of the use of pulverized coal for the years 1917 and 1918 has been compiled by the Library for the Institute. It comprises three typewritten sheets. Copies may be obtained by those interested at $2 per copy.

Jan 5, 1919