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By J. J. McKetta, O. L. Culberson

A preliminary investigation was made to determine the time required to attain equilibrium within the equilibrium cell for this system. Experimental and smoothed data are presented for the solubility of ethane in water for temperatures of 100°, 160°, 220°, 280" and 340 °F at pressures to 10.000 psia. The minimum solubility phenomenon disappears at 10,000 psia within this temperature range. INTRODUCTION .is a continuation of the investigation of the behavior of hydrocarbon-water systems, the experimental data on the solubility of ethane in water have been extended to 10,000 psia. The experimental apparatus, technique, materials, and analytical methods are essentially the same as previously reported.' TIME-CONCENTRATION STUDY Prior to the initial determinations of solubility in the ethane-water system. it was desired to establish the time

Jan 1, 1950

By A. J. Shaler, J. Prieto Isaza, John Wulff

TANTALUM metal has a number of unique properties which give it widespread application in modern technology and in research. In electronic apparatus involving high temperatures in vacuo some of the refractory metals become brittle. Tantalum retains its ductility at elevated temperatures, and this property, together with its low vapor pressure and its ability to absorb gases, make it important in this field. Its chemical inertness in the presence of acids, halogens, and other corrosive media, makes it useful in chemical apparatus and in neuro and orthopedic surgical applications. As an addition to tungsten carbide in steel-cutting grades of cemented-carbide tools, the carbides of tantalum and of its sister element columbium have found considerable use. The present-day method1 of manufacturing tantalum is to sinter a powder compact of the metal in vacuo. Because tantalum- columbium alloys are difficult to work and since tantalum ores almost always contain columbium, the two metals must be separated chemically, the products of the separation being generally in the form of potassium tantalum fluoride and potassium columbium oxyfluoride. These salts are used in fused-salt electrolytic baths from which coarse metallic powder is deposited as a sponge at the cathode. Finer powder can be made from the coarse product or from tantalum scrap by first submitting it to an embrittling heat treatment in hydrogen and then crushing it. The fine hydrogen- containing powder may subsequently be degassed in vacuo at a high temperature. Prompted by the success of others2,3 in the magnesium reduction of titanium and zirconium halides, one of the authors under- took4 an investigation of the thermo- chemistry of the reaction between solid magnesium and gaseous tantalum penta-chloride, a subject which had not previously been studied. He found that the heat of formation of tantalum pentachloride is approximately 364,250 cal per mol at temperatures lower than the melting point of magnesium. A value of 83 units was found for the standard entropy at these temperatures. With these values, it was shown that magnesium and tantalum pentachloride are capable of reacting exothermically at temperatures less than the melting point of magnesium, and that no great violence is to be expected when these substances are heated together. The exothermic nature of the reaction indicated that the process should be efficient and should not require much externally applied energy. Tantalum pentachloride is not commonlv made commercially, and any process using it therefore involves the subsidiary problem of producing and handling this substance. A series of experiments was carried out in which dried chlorine saturated with carbon tetrachloride was passed over heated tantalum, either in the metallic state or combined

Jan 1, 1947

By N. A. Ziegler

A CERTAIN amount of interest has been indicated recently in the resistance to oxidation at high temperatures of iron-aluminum alloys (rich in iron). Hautman1 published a paper in. which some interesting results are given. According to his paper, only alloys containing at least 8 per cent aluminum indicate a marked improvement in their resistance to oxidation. At about this aluminum content, however, alloys become brittle, which considerably reduces their commercial value. About two years ago the author, performed a series of experiments, the results of which are presented here. A series of iron-aluminum-carbon alloys was prepared by melting electrolytic iron, aluminum and high-carbon iron alloy in an induction vacuum furnace.2 The list of these alloys is given in Table 1. Each alloy was forged in the ordinary way to

Jan 1, 1932

By ERIIL SCHROEDTER

THE death, on May 6, 1908, of Dr. Hermann Wedding, Privy Mining Councilor of the Kingdom of Prussia, and Professor of the Metallurgy of Iron and Steel at the Royal Mining Academy of Berlin, was a loss keenly felt by the whole metallurgical world. Not alone in his native land, but also in foreign countries did he enjoy an esteem of which the title of honorary membership in the American Institute of Mining Engineers, the United States Association of Charcoal Iron-Workers, and the (British) Iron and Steel Institute bears eloquent testimony. Hermann Wedding was born March 9, 1834, in Berlin. At the suggestion of Dr. C. J. B. Karsten, the veteran father of Prussian metallurgy and author of the first German text-book of the metallurgy of iron, lie turned his attention, after gradu¬ating from the gymnasium, to mining and metallurgy. In 1853, he began a practical course at the Malapane iron-works, in Upper Silesia. Subsequently, he studied at the Berlin Mining Academy, and received from the University in 1859 the degree of Doctor of Philosophy. A journey which be made to England, somewhat later, led to his undertaking a German translation, with revision and additions, of John Percy's classic treatise on the metallurgy of iron and steel, the publication of which, in successive installments, stretched through many years. In 1863, lie published, as a thesis in connection with his "Assessor's examination," an essay, entitled The Results of the Bessemer Process for the Production of Steel, and Its Prospects for the Rhenish and Westphalian Iron and Steel Industry, which revealed such ability and knowledge as to secure for him a call to the chair of metallurgy in the Berlin Mining Academy.

Jun 1, 1909

By Eugene McAuliffe

THE Coal Division undertook its most ambitious program this year at the New York meeting, with six full' sessions and a luncheon on Monday which had a record attendance and at which the newly elected officers for the Division were announced. Eugene McAuliffe, president of the Union Pacific Coal Co., Omaha, Neb., was unanimously selected as Chairman; J. B. Morrow, preparation manager of the Pittsburgh Coal Co., as Vice-Chairman; and H. E. Nold, Ohio State University, Secretary. During the past year two new and interesting activities were conducted by the Division directed at stimulating the interest of junior and student members. Reports were presented at the luncheon meeting by the chairmen of these commit¬tees. J. B. Morrow. chairman of the paper prize awards, and H. N. Eavenson reported on the work of the mining machinery manufacturers fellowship, the work on which was completed the first of the year. Several excellent papers are expected from these two groups for the next meeting of the Division to be held in Pittsburgh some time in the fall. The regular six-session program was filled from start to finish with interesting papers and much discussion, but unfortunately not enough time for the latter. The papers covered the field of prospecting, mining methods, preparation, utilization, mechanization, and safety, and all through the program we were constantly reminded of the value and need of research in the coal industry.

Jan 1, 1936

The useful minerals can be subdivided into two large groups. One comprises those which are mined because of their chemical composition. They represent the natural resources of certain materials or of energy (coal). The second group is used not because of their chemical composition but because of certain physical properties or combinations of physical properties. A large number of minerals are mined because of their hardness, their electrical and thermal properties, their color or plasticity. There has been increasing recognition of the value of mineral synthesis during the past 30 years. This is illustrated by the development of improved aircraft spark plugs and chemical porcelain about the time of the first World War. During World War II the impact of crystal chemistry upon ceramics became most pronounced. New ceramic bodies were tailor-made, such as those designed with a high dielectric constant and low power loss, for use in high-voltage, high-frequency communication. In the field of refractories special materials were needed for unusual heat-resisting service in jet and rocket engines, and in the processing of fissionable materials. The synthesis of natural minerals in the laboratory has long been of aid to geologists and mineralogists in their study of the origin of minerals and physico-chemical conditions under which certain minerals were

Jan 1, 1950

By H. W. Johnson

DURING part of the year 1932, conditions at the plant of the Inland Steel Co. made possible the collection of data on two of the variables of blast-furnace operation, between which we observed an interesting correlation. The variation in percentage of coke ash in the coke seemed to be reflected in the variations in percentage of silicon and sulfur present in the iron. This subject is of particular interest during this period of low production because of its effect on quality and cost of pig iron. The consumers of pig iron are now more exacting in their requirements. Formerly 0.050 per cent sulfur was considered satisfactory; now many foundries and steel plants insist on iron under 0.030 per cent sulfur and expect it to average 0.025 per cent sulfur. To attempt to produce iron so low in sulfur and still have reasonably good furnace operation means that everything possible must be done to minimize all variations. This subject is also directly connected with the cost of producing iron. A blast furnace operates most economically and efficiently in rather narrow limits and so any variable that has range enough to disturb regular operation must be moderated. The importance of regularity is accepted and the methods followed to eliminate variations in materials such as coke and iron ore are recognized as indispensable. Uniformity of Ore and Variations in Coke Ash The delivering of uniform cargoes of well mixed ore to the blast furnace involves much handling and expense, but it is accepted that the trouble and expenditure are justified. After the ore reaches the dock, further mixing is assured by spreading ore in thin layers, preventing segregation by keeping piles level, variations in digging, and the use of several bins for one ore. And finally, the fact that the furnace burden generally contains three or more ores, together with several miscellaneous materials, eliminates the possibility of ill effects due to variations in any one. Thus, much effort is made to insure a uniform ore. But a variation in the percentage of silicon in ore is less detrimental than a variation in the percentage of ash in coke. The former affects

Jan 1, 1933

By Frederic E. Carter

THE gold, silver, copper alloys have been the subject of several fairly complete investigations by Jänecke, Sterner-Rainer1 and others, and indeed it would seem as if almost too much labor had been expended on them when one thinks of the numerous other ternary alloys calling for more light; however, the combinations of the three metals are actually so widely used in jewelry that they merit perhaps the work done on them. There are a few properties of importance and interest not treated by the authors mentioned which the writer investigated some little time ago, and therefore he has ventured to put on record the results of some of his tests made at that time. He has chosen, as being the two series of most importance to the jeweler, only the 14 and 18-kt. golds, so the subject is by no means so inclusive as that previously treated. As stated, this paper is merely a record of tests made in a practical manner on two useful series of alloys, and is not at all a critical study of their properties. 14-KARAT ALLOYS These alloys are important because they are the most generally used in 14-kt. jewelry; by changing the proportions of silver and copper there are obtained all shades of color from the green of the alloy containing gold and silver but no copper, to the red of the alloy containing gold and copper but no silver. Many 14-kt. gold alloys are made with the addition of zinc to the three metals mentioned here; the added metal does not appreciably alter the color of the alloy nor has it, in general, much effect on the working properties; it may, however, prove useful as part of the zinc added may act as a deoxidizer and render the alloy free of gas. It is not a necessary addition because with proper precautions all the 14-kt. gold alloys containing only silver and copper in addition to the gold can be made free of gas and capable of being cold rolled without cracking. The alloys in which approximately equal quantities of silver and copper

Jan 1, 1928

By AIME AIME

This section contains announcements of general interest to the members of the Institute, but not always of sufficient permanent value to warrant republication in the volumes of the Transactions.

Sep 1, 1906

The Library of the above-named Societies is open from 9 A.M. to 10 P.M. on all week-days, except holidays, from September 1 to June 30, and from 9 A.M. to 6 P.M. during July and August. The Library contains about 55,000 volumes, including sets of technical periodicals and the publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library can render valuable service through correspondence; letters requesting information will receive special attention. The Library is prepared to furnish references and copies of articles mining and metallurgical subjects; to determine the existence of mining maps, and to furnish general information as to the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape. The members of the Institute can be of service to the Library by forwarding copies of mining reports, maps privately issued, and similar material, which will be classified, indexed, and made available to other members. Suggestions for additions to the Library, either by purchase or personal solicitation as gifts, will be welcomed. It is hoped that members while in the city will use the Library freely, and assurance is given that most careful service will be rendered to them.

Jan 4, 1915

By Harlowe Hardinqe

ABOUT three years ago a distinctive new type of crushing and grinding equipment, known as the Hadsel mill, was announced. A description appeared in the November, 1932, issue of this magazine. Any machine that would take run-of-mine ore and reduce it, in one operation, and at a reasonable cost, to a size suitable for metallurgical treatment was bound to attract much interest, as the original Hadsel mill did. The first commercial sizes were built with the drum supported by an overhung shaft and partly immersed in a tank. The drum carried inside and outside buckets to lift the ore, which was dropped as the drum revolved onto stationary breaker plates projecting into the drum from the opposite tank wall. The coarser material settled back into the inside buckets. Intermediate sizes were carried into the tank, and this material was scooped out by the outside buckets and deposited hack in the drum for further grinding. The fines were carried out of the mill with the wash water over an adjustable weir at one side of the tank.

Jan 1, 1935

By W. C. Knopf, G. Samsel

For several years International Minerals & Chemical Corp. has used a radiation method to assay potassium content of products from potash and feldspar beneficiation. The procedure is rapid, accurate, and inexpensive and is easily handled, if necessary, by nontechnical personnel. Data are presented to show the accuracies that may be expected if the technique is used for control of pilot plants or large- scale plants. Natural potassium is composed of three isotopes -K39, K40 and K41. Five other isotopes, artificially produced, have been detected. In natural potassium only the K40 isotope, with a half life of 1.4 x 109 years, is radioactive. Its modes of decay are beta and gamma rays, positrons, and x-rays. Only the more abundant beta rays, however, are important in radiation measurements using geiger tubes.

Jan 10, 1958

By HILLARY W.

THAT colleges and technical schools constitute a vital factor in our industrial system is being realized more and more of late years. Consequently it is desirable that there should be a constant interchange of ideas between the 'school and the industries and that there should be a more intimate contact between the student and his future employer. Business and industry demand certain proficiencies and qualifications of the student and he, in turn, sees certain rewards and advantages in the industry. . In a meeting of this kind, whose primary purpose is to promote a greater intimacy between the students and those men who are active in the mining profession, it is quite fitting that each state his demnds upon the other in order to establish a common understanding. It is probable that a student, not being conversant with actual conditions in the industry, may be unfair in what he asks of his employer. Therefore criticism, constructive or other- wise, is not only accepted, but is invited.

Jan 1, 1930

By Knut Conradsen

In the study 208 heavy mineral concentrates (pan samples) from Jameson Land, East Greenland, are considered. Each concentrate has been analysed (by spectroscopy) for the content of (approx.) 25 elements. Furthermore the exact sampling position and the geological characteristics of the environment have been registered. In the study is shown how different multivariate methods combined with geological knowledge of the area can be used in the interpretation and classification of the data. Special emphasis is put on the problem of finding reliable expressions for the background level of the element concentrations in the area. This is done by means of severel discrimination procedures. The other main subject is a demonstration of the applicability of isoscore maps - originating from factor analyses - in the evaluation of the co-variability of the data, and thus give another way of classifying the individual samples according to the content of different elements.

Jan 1, 1977

By D. S. Hutton, W. C. Leslie

S. Floreen (1nteumtio)lal Nickel Co.)— One fairly simple way to differentiate between embrittlement due to surface microcracks or due to a dislocation barrier effect might be to load a brittle rock salt crystal in tension to some stress just below the fracture stress and then immerse the loaded crystal in water. If a surface film is retarding plastic flow then one should observe some plastic deformation of the rock salt as

Jan 1, 1962

By R. W. Hunt

One of the serious and important economic administrative problems facing American railway authorities today is that of their rails, and it is one to which much thought is being given…

Jan 1, 1915

By W. A. Wood, W. H. Reimann, Maria Ronay

The basic mechanism of fatigue is studied in annealed a brass subjectecl to alternating torsion at room temperature, 100°, 200°, 300°, and 400°C, and in air. It is shown that the slip-zone micro-cracking which characterizes fatigue damage produced by small amplitudes at room temperature is progressively replaced by grain boundary cracking at elevated temperatures, replacement being complete at 400°C. Replacement occurs not because slip activity decreases hut because slip movements at elevated temperatures cease to concentrate in narrow zones and instead disperse. Decrease of amplitude at 400°C through permitting longer lives of specimens before fracture actually causes in- MOST studies of fatigue at elevated temperature have been concerned with data for design. Observations on the basic mechanism of fatigue have been largely incidental, though they have led to the interesting inference that this mechanism has features in common with that of creep.' This paper is concerned primarily with the mechanism itself. Advantage has been taken of mater- crease in pain boundary damage, an anomaly attributed to the greater difficulty at elevated tempwature of starting and propagating a crack. Surface corrosion was most pronounced along slip bands but since at elevated temperatures the slip hands showed no cracking the surface corrosion did not appear to influence onset and early spread of fatigue damage. Similarly the type of fatigue damage produced at room temperature by cyclic strain at large amplitudes, characterized by irregular mi-crocracks at zones between disoriented regions in a grain, was also replaced by mainly grain boundary cracking at elevated temperature, though not so completely. ials and procedures known to show readily how fatigue affects the microstructure of a metal at room temperature, so that direct comparison might be made with what the same procedures show when the material is subjected to fatigue deformation at higher temperatures. 1) MATERIAL This was 70/30 a brass, used extensively in previous studies at room temperature.' Specimens were turned from extruded rod to have parallel test portions 1-1/4 in. long and 7/32 in. diameter, annealed to a grain size -1/10 mm, and electro-

Jan 1, 1965

By E. N. Cameron, H. M. Bannerman

During the years 1942-1934, about 125 New England deposits were mined for sheet and punch mica, and many others were briefly prospected. During this period the Geological Survey, United States Department of the Interior, carried on detailcd studies of the deposits and the pegmatite bodies that contain them. The primary purpose of the studies was to provide geological information that would contribute toward efficient mine development and operation. The studies were aimed directly at practical production problems. Detailed maps showing the structure of the deposits were prepared, and geological findings were closely correlated with data on specific yields and costs of mining and processing. The result is information that permits a reasonably accurate appraisal of the mica deposits of New England and the mining industry that they support. At a time when the future of the industry is in doubt, it seems desirable to submit this appraisal for consideration. Domestic mica deposits supply only a small fraction of the country's needs in normal times? for only the richest domestic deposits can compete with the low-cost mines of India and Brazil. However, the possibility that this country may be cut off from its supplies in time of war gives domestic deposits an importance much greater than their peacetime production would imply. New England supplied about 22 per cent of domestic output in 1943 and 1944, the peak years of wartime production. Its actual contribution to the war effort was greater, for the proportion of sheet mica of high quality in the New England product is higher than the average for domestic mica. The data analyzed below were collected for the Geological Survey by D. M. Larra-bee, A. H. McNair, J. J. Page, V. E. Shai-nin, G. W. Stewart, and the co-authors of this paper. The cooperation of officials of Colonial Mica Corporation and of mine operators and owners in furnishing information is gratefully acknowledged. D. M. Larrabee, A. H. McNair, and V. E. Shainin have made various suggestions based on critical reading of the manuscript. Analysis oF Warrtime Operations In considering the data presented in this report, it must be remembered that the scale of mica operations is very small compared with that of many other mining industries. The typical New England mica mine of 1943 and 1944 was worked by a crew of five or six men. Equipment was varied but on the whole extremely simple. The first stage of operation at a deposit was normally opencut mining. Drilling was done mostly with jackhammers powered by portable compressors driven by gasoline engines. Muck was shoveled by hand into buckets with a capacity of 45 to 35 ton and commonly hoisted by derrick to a dump adjacent to the cut. As operations were carried to greater depth, and the tram sition to underground mining was made, these methods were modified to a degree depending largely on the attitude of the deposit mined. At steeply dipping deposits,

Jan 1, 1948

By H. M. Bannerman, E. N. Cameron

During the years 1942-1934, about 125 New England deposits were mined for sheet and punch mica, and many others were briefly prospected. During this period the Geological Survey, United States Department of the Interior, carried on detailcd studies of the deposits and the pegmatite bodies that contain them. The primary purpose of the studies was to provide geological information that would contribute toward efficient mine development and operation. The studies were aimed directly at practical production problems. Detailed maps showing the structure of the deposits were prepared, and geological findings were closely correlated with data on specific yields and costs of mining and processing. The result is information that permits a reasonably accurate appraisal of the mica deposits of New England and the mining industry that they support. At a time when the future of the industry is in doubt, it seems desirable to submit this appraisal for consideration. Domestic mica deposits supply only a small fraction of the country's needs in normal times? for only the richest domestic deposits can compete with the low-cost mines of India and Brazil. However, the possibility that this country may be cut off from its supplies in time of war gives domestic deposits an importance much greater than their peacetime production would imply. New England supplied about 22 per cent of domestic output in 1943 and 1944, the peak years of wartime production. Its actual contribution to the war effort was greater, for the proportion of sheet mica of high quality in the New England product is higher than the average for domestic mica. The data analyzed below were collected for the Geological Survey by D. M. Larra-bee, A. H. McNair, J. J. Page, V. E. Shai-nin, G. W. Stewart, and the co-authors of this paper. The cooperation of officials of Colonial Mica Corporation and of mine operators and owners in furnishing information is gratefully acknowledged. D. M. Larrabee, A. H. McNair, and V. E. Shainin have made various suggestions based on critical reading of the manuscript. Analysis oF Warrtime Operations In considering the data presented in this report, it must be remembered that the scale of mica operations is very small compared with that of many other mining industries. The typical New England mica mine of 1943 and 1944 was worked by a crew of five or six men. Equipment was varied but on the whole extremely simple. The first stage of operation at a deposit was normally opencut mining. Drilling was done mostly with jackhammers powered by portable compressors driven by gasoline engines. Muck was shoveled by hand into buckets with a capacity of 45 to 35 ton and commonly hoisted by derrick to a dump adjacent to the cut. As operations were carried to greater depth, and the tram sition to underground mining was made, these methods were modified to a degree depending largely on the attitude of the deposit mined. At steeply dipping deposits,

Jan 1, 1948

By S. R. B. Cooke, H. S. Choi, I. Iwasaki

Oleic acid is the chief ingredient of fatty acids used as collectors in nonsulfide flotation. With a few notable exceptions, the various quantities of saturated and other unsaturated acids comprising the remainder are usually unspecified. There have been occasional investigations to determine the collecting ability of these other acids and their effect on collection with oleic acid, but much remains to be done in this field. Hukki and Vartiainen, on the basis of tests using palmitic, oleic, and linoleic acids and an impure linolenic acid, concluded: "The collecting power of fatty acids used in flotation increases with increasing unsaturation of the hydrocarbon chain." ' Their work was concerned mainly with the response of ilmenite to the foregoing collectors, although tests were also made with magnetite, pyrite, hematite, and rutile. Cooke and Nummela, employing an almost identical technical procedure to evaluate flotation of hematite, magnetite, and goethite with various fatty acids, including oleic, linoleic, and linolenic acids of the highest purity obtainable, found: "The effectiveness of 18-carbon unsaturated fatty acids, as collectors for hematite, decreases with increase in the number of non-conjugated double bonds." 2 Vn the foregoing investigations, collector efficacy was measured on the basis of reagent addition in moles per liter. Sources of fatty acids which may be used as collectors are legion, but provided the oleic acid content is high enough, cost is normally the determining factor. Usually this restricts severely the purity of the collector in terms of its oleic acid content. Within the past year or so users of crude oleic acid have become somewhat more discriminating, apparently realizing that some of the organic acid impurities may exert deleterious effects upon certain separations. Marine fish oils have been used as collecting agents, particularly in the earlier days of froth flotation. Currently their use is restricted in this field to relatively minor applications, although they are cheap sources of fatty acids. In an effort to increase the range of uses for fish oils, the U. S. Fish and Wildlife Service has awarded contracts to study these materials as sources of new products suitable for commercial development. Funds for these investigations were provided by the Saltonstall-Ken-nedy Act of 1954. One such contract was awarded to the University of Minnesota School of Mines and Metallurgy for the purpose of investigating the use of fish oil fatty acids and their derivatives in ore flotation. Besides the esters of various saturated aliphatic acids and of palmitoleic and oleic acids, fish oil also contains esters of monoethenoid and polyethenoid acids with 20, 22, and 2 carbon atoms. The basic purpose of the investigation was to determine whether the longer-chained unsaturated acids possess collective properties superior to those of the C,, monoethenoid oleic acid, the C16 monoethenoid palmitoleic acid, or the saturated C,, stearic acid and its shorter chain homologues; whether highly unsaturated acids have merit as collectors; whether rela-

Jan 1, 1960