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Flaubert, as we know, laid stress on the selection of the right word, le mot juste, the precise epithet, the word that belongs to the thing. A sentence, or even a paragraph, may be spoiled. by the use of a word that is not proper, that does not fit or is foreign to the meaning intended. An Australian mining expert is reported to have said: You have a property of considerable value, and what I saw warrants s good development of very rich cubicular galena, with gossan intermixed. 'Cubicular' means 'belonging to a small bedroom', a 'cubicle' being a sleeping compartment. He meant 'cubic', of course. This is a malapropism, and reminds me of the lady from Chicago that, on her return from Europe, said how much she had enjoyed the rural parts of France, because, among other things, it was "so delightful to hear the French pheasants singing the mayonnaise to the tune of the Los Angelus". It is impossible to amalgamate coal-tar thoroughly with the pulp in the agitating-tank. In metallurgy, 'amalgamate' refers to the combination of mercury with one or both of the precious metals, forming an amalgam, which is an alloy of mercury with another metal. It differs from other alloys, such as brass or bronze, in being made without the aid of heat, inasmuch as mercury is molten at the ordinary temperature. The word comes to us from the Greek through Old French and means 'something soft'. It is a mistake to use technical terms, having a specific meaning, for purposes that are foreign to that meaning. The writer of the quotation is not discussing any combination of metals; he is dealing with the physical process of mixing and is using 'amal-

Jan 1, 1931

By J. W. Furness

Before attempting any discussion of the importance of tariff enactments as applied to exhaustible resources, certain basic factors should be emphasized. First, it must be remembered that minerals differ from organic substances in that they are irreplaceable, and when once taken from the earth's crust enter into uses which ultimately dissipate them, so . that they cannot be recovered for future use. A second factor entering into the problem is the unequal distribution of the mineral deposits of the world. No industrial nation has within its political confines a sufficient quantity of all the minerals necessary for the maintenance and advancement of present civilization; hence international exchange of these commodities is inevitable. As minerals are essential to modern industry, the supply available to any given nation constitutes a factor which limits its ambition to advance industrially. A nation which has this ambition endeavors to secure not only a supply of minerals sufficient for its current needs, but also sources which will assure it expansion. Should mineral raw materials be withheld from such a nation by enactment, it seems inevitable that every effort will be made to obtain them, and that, should the nation deem itself sufficiently powerful, its ultimate recourse will be force. Thus the importance of tariff enactments, not only from the standpoint of industrial prosperity but from the standpoint of international peace, can be appreciated.

Jan 1, 1932

By B. H. Caudle, M. D. Witte

In predicting the performance of a pattern injection operation, the engineer needs to know both the amount of oil to be recovered and the rate at which the recovcry will take place. This paper- describes fluid flow model studies on the effect of mobility ratio on the rate of oil recovery in a five-spot. The results show the change in fluid conductivity (total flow rate/pressure drop) as the sweep-ont pattern increases for mobility ratios between 0.1 (and 10. There data, when cornbitted with a knowledge of reservoir permeabilities and sweep-orit pattern efficiencies, cata he used to predict the cLrmulntivr oil production as a function of time for homogeneous five-spot injection systems. INTRODUCTION The flow potential in a pattern flood element is a function of the mobility ratio and how far the injected flood front has gone.1,2 For a waterflood project having a mobility ratio of one, the conductance—which is the flow rate per unit pressure drop (q/Ap)—-will remain the same throughout the life of the flood. If the mobility ratio is favorable ( < I), the conductance of the project will drop continuously throughout the operation. If, on the other hand, the mobility ratio is unfavorahlc. the conductance ratio will increase continuously. Therefore, if the reservoir engineer wishes to predict either the rate at a specified pressure or the pressure at some rate for a secondary recovery project, he must know how the conductance will vary during the flood. Other investigators have studied this problem using potentiometric models&apos; or analytical solution&apos;. The

By J. E. Korski

Quebec Cartier Mining Co. operates a low-grade iron ore deposit at Lac Jeannine, Que., which is located at the extreme southwestern end of the Quebec-Labrador Trough (Fig. 1). The facilities there include one of the world&apos;s largest concentrators, a hydroelectric plant of 60,000 hp, and the modern town of Gagnon. A 191-mile railway connects the mine to the seaport situated at Port Cartier on the St. Lawrence River. The harbor in Port Cartier can accommodate both lake and large ocean- going vessels and is also the site of a major grain terminal. The concentrator in Lac Jeannine is designed to produce some 8 million tpy (tons per year) of specular hematite concentrate, containing 66% Fe, from approximately 20 million tons of crude ore. An annual stripping program of 5 to 8 million cu yd of waste rock uncovers the required ore. Approximately 100,000 tons of ore and waste are removed daily on a year-round, 24-hr-per-day basis. The open pit covers an area with maximum dimensions of 8,000 x 2,600 ft (Fig. 2). Present mining plans call for an ultimate depth of approximately 1,000 ft below original ground level. The rocks in the pit area are typical of this portion of the Grenville geological province. They consist largely of marble, quartz rock, pegmatite, iron formation, and stratigraphically older gneisses. The iron-ore formation consists of medium to coarse-grained specular hematite in a quartz host rock. The formation occurs locally in a plunging, anticlinal form. The topography in the vicinity of the mine is rolling, with maximum variations in elevation of about 400 ft. The hills are thickly wooded with birch, black spruce, and some tamarack. Lakes and muskeg areas are plentiful. Precipitation and temperature records have been kept since 1959. The annual rainfall has ranged between a low of 23 in. and a high of 42 in.

Jan 1, 1969

By Arthur B. Cummins, Henry Mulryan

DIATOMITE is a hydrous or opaline form of silica, commonly known as diatomaceous earth, diatomaceous silica or kieselguhr. The term "infusorial earth" has lost its original meaning and today is incorrect in view of the distinctions between diatoms and infusoria. Various locality and variety names are obsolete but some retain local significance. Moler and Celite are trade names that have become associated with diatomite products from certain deposits in Denmark and near Lompoc, California. COMPOSITION Diatomite is essentially silica with some combined water (2 to 10 pct). Frequently it contains organic matter (from traces up to over 30 pct) and varying amounts of inorganic impurities such as sand, cryptocrystalline silica, clay, volcanic ash, calcium carbonate, magnesia and soluble salts. In the natural or crude state, diatomite contains from 10 to 65 pct or more of free water. Table I gives analyses of several diatomites from deposits of different types. PROPERTIES Pure varieties, either massive or stratified, are friable and porous, of low apparent density, and somewhat chalklike in appearance. Varieties containing organic matter vary from sedimentary oozes to peatlike materials. Impure varieties may be more or less claylike, sandy, calcareous or cherty. Compacted types approach porcellanite and silicified shales. COLOR-white, cream, gray, tan, brown, greenish to nearly black. HARDNES-light-weight varieties appear 1 to 1.5 because of porosity, but microscopic particles are 4.5 to 6.5. SPECIFIC GRAVITY-1.9 to 2.35. APPARENT DENSITY---dry block form, 20 to 40 lb per cu ft; dry powder, 5 to 16 lb per cu ft. CRYSTAL SYSTEM-generally amorphous (isotropic by X-ray diffraction) but frequently showing faint cristobalite pattern.67.68,70 MELTING POINT-1400° to 1650°C. STREAK-white. LUSTER

Jan 1, 1949

By Stanley J. LeFond, Langtry E. Lynd

Elemental titanium has become famous as a space age metal, because of its high strength/ weight ratio and resistance to corrosion. However, the major use is in the form of titanium dioxide pigment, which because of its whiteness, high refractive index, and resulting light-scattering ability, is unequaled for whitening paints, paper, rubber, plastics, and other materials. A relatively minor use is in welding rod coatings, in the form of the mineral, rutile. United States consumption of titanium dioxide for these applications in 1973 was as follows: pigments, 891,000 st; titanium metal, 40,000 st (=24,000 st metal) ; and welding rod coatings, 10,000 st. The only commercially important titanium ore minerals at the present time are ilmenite, and its alteration products, and rutile. Titanium was discovered by Gregor in 1790, as a white oxide which he recovered from menaccanite, a variety of ilmenite occurring as a black sand near Falmouth, Cornwall. Barksdale (1966) states that the fundamental chemical reactions on which the present day titanium industry is based were known before 1800, although it was not until 1918 that these pigments were available commercially on the American market. Pings (1972) outlines the early history of the titanium industry in the United States, referring to the work of Guise (1964) and others: "Mining of titanium minerals in the United States began sometime between 1880 and 1900, in Chester County, Pennsylvania. Small quantities of rutile were also produced during the time in North Carolina and Georgia. In 1901 rutile was mined from a deposit near Roseland, Va., and was used in making titanium chemicals and for coloring ceramics. Ilmenite in the deposit was produced as a separate item in 1913, and rutile and ilmenite were obtained from this deposit through 1921. The mining of titanium bearing beach sands began in 1916 near Mineral City and Pablo Beach, Fla., for the purpose of making titanium tetrachloride to be used in tracer bullets, flares, and smokescreens. The titanium pigment industry was founded in 1918. By 1928 a large part of the domestic production of rutile, ilmenite, and zircon came from Florida. However production ceased in 1929 in Florida with the mining of newly discovered deposits in Virginia which were mined until 1968. The discovery of new deposits in Florida, and the development of better mining and concentrating methods for lowgrade sands, led to a return of activities in this area. The large deposits near Tahawus, N.Y., were brought into production in 1942 by National Lead Co. (now N L Industries Inc.), and by 1949 this company was the lead¬ing producer of ilmenite in the world. In 1948 the extensive deposits of ilmenite and ilmenite-bearing iron ores were discovered in eastern Quebec." The beginning of the modern titanium metal industry was in 1948, when E. I. du Pont de Nemours & Co. produced the first metal. U.S. Bureau of Mines reports, which gave details of the Kroll process, together with the attractive properties of the metal for

Jan 1, 1975

By S. W. Ross

In 1936 a description of the plant (Fig 1) and process employed by the Electrolytic Zinc Co. of Australasia Ltd. for the recovery of zinc from zinc concentrate by the electrolytic process was prepared. † During the twelve years which have elapsed since the preparation of the earlier paper, several major changes in the metallurgy of the process have been introduced. It is the purpose of the present paper to give a general description of these changes and thus to bring up to date the description of the plant and process. Summary The major changes in Risdon practice since 1936 have been: 1. Replacement of two stage roasting by a preliminary roast followed by the flotation of all the leach residue and the roasting of the flotation concentrate. 2. Screening of all calcine fed to the pachucas. 3. Continuous leaching of calcine and improved classification of pachuca discharge. 4. Close control of hydrogen ion concentration during purification for iron removal. 5. Recovery of cobalt as a good grade oxide. 6. Production of part of the zinc output in the form of "four nines" metal (99.99 pct purity). 7. Closer spacing of electrodes thus increasing the potential output of cathode zinc per cell by 50 pct. Changes which are in prospect and for which construction work is proceeding at the present time involve the starting up of: 1. Two suspension roasters. 2. A contact acid plant to produce 150 tons‡ of acid per day and replacing the existing Mills Packard chamber plant. 3. Extra power station capacity to permit greater current flow to existing cell room units. This will increase the output of cathode zinc from about 245 to 290 tons per day. Plans for the future envisage the building of an ammonium sulphate plant, the first unit of which will produce about 50,000 tons per year, and improved treatment of zinc plant residue for the recovery of zinc, lead and other metals. At the end of this paper tables of metallurgical data are presented relating to the year ending June 30, 1948. Details of Changed Practice Output In 1936 the production of cathode zinc amounted to about 200 tons per day. This has since been increased to about 245 tons per day while plant extensions are practically complete which will permit of an output of about 290 tons per day in the near future. Roasting Division ROASTING POLICY A major change has occurred in the roasting policy. Twelve years ago the method in use was to carry out a two stage roast in the first stage of which sulphide sulphur was reduced to about 6 pct. The pre-roast calcine was re-roasted in modified Leggo furnaces using coal as fuel, sulphide sulphur being reduced to about 0.8 pct. The whole procedure was described on pp. 482491 of the earlier paper. Although this roasting procedure had certain advantages it possessed some distinct disadvantages. For instance, it appeared uneconomical to heat up the entire input of pre-roast calcine to roasting temperature by the expenditure of fuel in order to oxidise a few percent of sulphide sulphur. It was argued that if the pre-roast calcine were leached and a process could be developed for the recovery of a zinc sulphide concentrate from the leach residue, this concentrate, small in weight compared with the pre-roost calcine, would probably roast autogenously, thus virtually eliminating the expenditure of fuel as well as greatly increasing the weight of sulphur oxidised per square foot of furnace hearth area. The obvious method of producing a suitable concentrate from leach residue was by flotation. It will be recalled (see p. 495 of the earlier paper) that when two-stage roasting was practised the leach residue was classified, the granular fraction was ground and floated while the slime fraction was thickened, filtered and dried ready for shipment to a lead smelter. This process worked quite successfully. However, when trials were made of leaching a calcine carrying several percent of sulphide sulphur the granular fraction still floated well, but the slime fraction carrying 8-10 pct sulphide sulphur yielded very poor results when subjected to flotation. This fact held up the application of "pre-roast" leaching for many years. However, successful flotation of the slime fraction of leach residue was finally achieved and in August 1940 the slime flotation plant began operation, while the leach-

Jan 1, 1950

By Alfred Fisher

CONSERVATION of mine timber is becoming in-creasingly important, and the consumer is en-couraged to use treated wood to permit longer life of mine timbers, and attempts are also made to substitute other material for wood. The great diffi-culty in substituting metal and concrete props for wood is the inability of these to give yielding resistance to roof pressure as wood supports do. In Europe, where mine timber costs are somewhat more important than in America, many designs of steel props have been tried, but have been unsuccessful, chiefly on account of inability to give yielding resistances. A metal pit prop that gives the desired effect has been extensively used in European mines and has caused a considerable reduction in accidents from falls of roof. Where mining operations have been sus-pended on account of strikes, conditions were found to be much better where such props were used instead of wood props, and machinery, which would have been destroyed by roof falls had wood props been used, was protected by the use of these yielding metal props. As this prop is adjustable, all the work of adjusting and transferring long props through narrow ways is done away with. It can also be drawn with greater ease and safety than wooden props; when properly used it is practically indestructible. European users have reported savings as against wooden props as high as 80 per cent. It gives audible warning of its working because the sliding action takes place in minute jerks. As the prop yields gradually to pressure its force is taken up by friction between the H sections, and this movement progressively increases the resistance of the prop to the increasing roof pressure. In the early development of the prop, it was designed with two steel members a and b of standard H steel sec-tions of equal dimensions provided with guide claws a&apos; and b&apos;, held in frictional contact against each other by two differential wedges, f and g, and a floating link, e. In setting up the prop its two members are drawn out to the required length, the loose wedge, g, is then fitted into the space between the left-hand roller of the link d and the lower member of the prop b, and tapped suf-ficiently tight to prevent any relative movement of the two members from taking place prematurely. The prop is then raised to its intended position and secured in the usual way.

Jan 8, 1927

By Katherine Mather

This paper is an attempt to put together petrographic, physical, and chemical data about the large and varied group of rocks generally called limestones. Results of the properties of these rocks on their performance as concrete aggregates are discussed. CRUSHED stone classified as limestone comprises about 70 pct of the crushed concrete aggregate and roadstone produced in this country, and the product has amounted in the recent past to about 97 million tons per year, valued at more than $123,-000,000.&apos; Therefore an evaluation of the properties of rocks classified in these statistics as limestones and an ability to predict their behavior as aggregate in portland cement concrete are matters of considerable economic consequence to producers and consumers of aggregate. This paper is an attempt to put together petrographic, physical, and chemical data about the large and varied group of rocks generally called limestones. It also points out certain results of the properties of these rocks on their performance as concrete aggregates. The problems encountered in efforts to explain the behavior of limestones, dolomites, and related rocks as concrete aggregate lie on the frontiers between the ignorance of the geologists and the ignorance of the engineers. The mineral composition and textures of the rocks have not been adequately explored and described, and the effects of mineral composition and texture on the performance of aggregates have been worked out in only a few cases. There are instances of unsatisfactory performance and some generalizations of those experiences. There are many more examples of satisfactory performance than of unsatisfactory, but there is practically no published information as to why a particular aggregate was satisfactory in a specific use. There are all too few investigations of undeteriorated concrete; more is known about the pathology of concrete than about its normal structure and aspect. As part of the investigation of aggregates, the classification of rocks is not an end in itself, but is a step toward recognition of properties expected to influence the behavior of aggregates in their intended use. Rock of any type may perform well or poorly as concrete aggregate, depending on the physical condition of the rock, its physical and chemical properties as compared to those of the matrix in which it is placed, and the circumstances under which the concrete is exposed. Some classification and descrip- tion of the limestones is necessary to distinguish subgroups whose members will probably behave in similar ways and to evaluate the group as a whole. The group name, limestone, includes and tends to conceal the identity of rocks that have a very great range in chemical and mineralogical composition, structure and texture, conditions of deposition, subsequent history, and suitability for use as concrete aggregate. All the rocks classified as limestones include one or both of the most abundant rock-form-ing carbonate minerals, calcite and dolomite, as major constituents. Carbonate rocks is a more descriptive and more accurate group name than limestone, which has generally been used to include dol-omitic or magnesian limestones and dolomites as well as calcitic limestones. Classification and Description of the Carbonate Rocks The question of names to be applied to the carbonate rocks may appear academic, but it is of practical importance as long as there are specifications for aggregate that result in acceptance or rejection of rocks by name and as long as failure to make distinctions among the carbonate rocks leads to misunderstandings of their properties and of what may be expected of them in performance. Materials included in production statistics as limestone and tested for concrete aggregate as limestone range in fact from calcareous shale and calcareous or dolomitic sandstone and argillaceous limestone and dolomite to calcitic limestone and pure dolomite and to rocks close to calcitic and dolomitic marble. To take a simple example: consider two manufactured coarse aggregates, both dense and unweathered, one composed principally of crystalline calcite and the other of crystalline dolomite, but both known as limestone. If each is used as coarse aggregate in a standardized concrete mixture with the same fine aggregate used in both cases, made into concrete specimens, and tested in accelerated freezing-and-thaw-ing, the test results will probably be quite different, because of the differences in internal bond and thermal properties between the two aggregates. As long as both aggregates are called limestone, the test results cannot be explained, or used except in a very limited way; if the aggregates are distinguished as limestone and dolomite and the consequent differences in texture and thermal properties are recognized, the results are reasonable. Classification of the carbonate rocks used as aggregate should be based on structure and on composi-

Jan 1, 1954

By J. R. Dolegowski, W. S. Jensen, S. M. Olafson, W. H. Champion, G. A. Kordosky

The use of pH control in solvent extraction circuits to aid in metal separation, concentration, and purification is an extremely useful technique applicable to a wide range of solutions. This paper discusses the technique in general and then gives examples of its use in extraction stages, wash and/or scrub stages, and in stripping stages, to effect the desired metal separation, concentration, and purification. Specific examples cited include Cu-Ni, Cu-Zn, and U-Mo separations using commercially available liquid ion exchange reagents.

Jan 1, 1982

By F. J. Plecity, J. T. Michalak, W. C. Leslie

Isothermal recrystallization and grain growth in zone- and vacuum-melted irons and Fe-Mn alloys, up to 0.60 pct Mn, were studied in the range 480° to 650° C, after 60 pct cold reduction. In initial stages, rate of grain growth and rate of recrystallization of iron decrease with time. The recrystallization is typical of a growth-controlled process, and rate of growth is determined by the extent of recovery. Mn decreases rates of growth and of recrystallizatzon. The recrystallization process changes at about 0.30 pct Mn and nucleation may become time-depetzdet~t. In recent years, considerable effort has been expended in determining the effects of solute elements on recrystallization and boundary migration in fcc metals. The results have indicated that the effects produced by single solute additions are dependent upon both the element added and its concentration.&apos;-&apos; In contrast, there have been very few attempts to determine the characteristics of recrystallization and boundary migration in high-purity bcc metals, especially after heavy deformation, and the effects thereon of single solute elements.9-11 This study was undertaken to determine the recrystallization characteristics of various "high-purity" irons and the effects of manganese additions at two levels of base purity. It was hoped that the information obtained would improve our understanding of the recrystallization of pure metals and aid in formulating a theory for the effect of solute elements. The interest was not entirely academic, for the annealing of low-carbon steels, which is of very great commercial importance, is but poorly understood. MATERIALS The compositions of the irons and iron-manganese alloys used are listed in Table I. The zone-melted iron and Fe-Mn alloys were made by Battelle Memorial Institute. Iron S-1 was arc-melted in a water-cooled steel mold in an argon atmosphere. The ingot was forged into a bar, then given two horizontal zone-refining passes in an alumina boat. Iron V-4 was treated in a similar manner, but was not zone-refined. The iron for the zone-melted Fe-Mn alloys was induction melted in vacuum in MgO crucibles and cast into alumina molds. The ingots were forged into bars, machined to shape, and a groove milled down one side of each. The best available electrolytic Mn was placed in the grooves, and the bars were zone melted. The vacuum-melted Fe-Mn alloys were induction melted in this Laboratory in MgO crucibles and poured into cast-iron molds. Iron V-5 was purchased from National Research Corp. in the form of a small vacuum-cast ingot. The low-carbon steel was made by induction melting in air at the U.S. Steel Corp. Applied Research Laboratory. The history of the materials prior to the final cold reduction differed; these details are given in the Appendix. The penultimate grain size of the principal materials was kept in the range ASTM 2 to 4, except for the low-carbon steel. PROCEDURES The cold work prior to the final recrystallization anneal was kept constant at 60 pct. It is known that rolling procedure can influence the kinetics of recrystallization of ironI2; therefore, all specimens were rolled in one direction only, between clean,

Jan 1, 1962

By C. E. Sims, H. M. Banta, S. L. Hoyt

Over the past few years, metallic arc welding has been extended to steels of the hardenable type. As compared with other methods of fabrication, production has been facilitated, service performance frequently has been improved, and the overall results have been so favorable that engineers and production men have placed great emphasis on this application of welding. The metallurgist and welding engineer, however, have been confronted with new problems, since, for one reason, the harder steels are more apt to crack and special precautions must be taken if sound joints are to be procured. Some of the factors that are pertinent to this problem are metallurgical, and it is an object of this contribution to discuss steel manufacture and processing methods and to show how their control assists in reducing the hazard of cracking. By this time, the problem of cracking— specifically underbead cracking, or "hard cracks," or parent-metal cracks-—is well known, and a large amount of work has been published, both here and abroad, dealing with this subject.&apos; The tests described are made under restraint to facilitate cracking and arc so designed that a semiquantitative, or at least a relative, value of the cracking tendency is obtained. As one would expect, it has been reported that the incidence of cracking increases with the carbon and alloy content of the steel. More specifically, the cracking tendency is said to increase with the hardenability of the steel, though it is now recognized that the situation is not so simple. The phenomenon itself, on the other hand, has been but loosely described, and it is in only broad generalizations that this cracking has been related to steel metallurgy. Thus, while it has been abundantly demonstrated that the hardenable aircraft steel, S.A.E. 4130, must tend to crack when are-welded, the problem still remains of why two lots of the same composition and the same hardenability can vary so greatly in cracking tendency, or what it is about the prior metallurgical history that so strongly affects the results. Further, while the efficacy of preheating and postheating in preventing cracking is recognized and utilized in production, the mechanism by which they function seems not to have been described. These points are thought to be significant in the production of steel for fabrication by metallic arc welding and, hence, of interest to mill and process metallurgists and welding engineers. Consequently, it is another object of this paper to discuss the mechanism of parent-metal cracking, including the influence of the condition of the steel and the control of cracking by manipulation of the time-temperature conditions during and after welding. A new method of rating the cracking tendency is also discussed, and the results of the test are related to steel composition and structure or prior history. The work to be described was the outgrowth of work in 1940-41 at Battelle Memorial Institutc on two projects, one

Jan 1, 1945

By H. E. Stauss, G. Sandoz

AN increase in the value of magnetostriction1 * is known to result from the annealing of some ferromagnetic alloys in a magnetic field. Similar increases may be anticipated in the value of the magnetostriction of alloys that are of interest because of their normal high values. Two were selected for trial, 87 pct Fe-13 pct Al(Fe,Al) and 69 pct Co-31 pct Fe, the latter being used as a representative of the Co-Fe alloy series. The influence of a magnetic field present during annealing is explained by the domain theory of magnetism." The field orients the domain vectors in its own direction when the alloy is at or below the Curie temperature, and holds them there until the metal is cold. During cooling the interaction stresses between neighboring grains are largely relaxed. Interaction stresses will reappear, however, if the state of magnetization of the specimen is changed in any way, and will be larger the more the new state of magnetization differs from the one existing during the magnetic anneal. In this connection the 180" reversal of a magnetization vector is not considered a change because a simple reversal does not tend to produce a change in shape of a magnetized region. When the field existing during the anneal is removed after the metal is cold, the domain vectors can turn back only to the nearest crystallographic directions of easy magnetization because return to random

Jan 1, 1953

By Glenn A. Marsh, George Bernard

It is often assumed that aerated oil field brines which are to be injected underground contain dissolved oxygen in amounts which will cause appreciable corrosion. Through the use of a new portable dissolved oxygen meter, accurate determinations were made at three brine conditioning plants. At two older plants, dissolved oxygen concentration in the final treated brine was found to he almost zero In spite of aeration during the conditioning process. At a new plant, dissolved oxygen was initially present but disappeared soon after the brine was "inoculated" with oxygen-free brine from one of the other plants. Corrosion tests at the two older plants have substantiated predictions that the brines would lint be corrosive. These results show that mechanical deaeration may not always be required in brine treating plants. INTRODUCTION The present work was undertaken to add to our knowledge of aeration and deaeration of oil field brines in brine conditioning plants. It is commonly assumed that brines which are exposed to the air soon become more or less saturated with dissolved oxygen. Since oxygen-containing brines are known to be corrosive, precautions are often taken to keep air out of brine through the use of closed systems or mechanical deaeration. The study of oxygen in brine has been seriously hampered in the past because of the lack of a suitable analytical tool. The standard Winkler method for the determination of dis-solved oxygen is satisfactory for use in fresh water, but not in many oil field brines. Corrections have to be made for a number of reducing substances such as ferrous iron and hydrogen sulfide which are commonly present in natural brines. Very often the correction factors are much greater in magnitude than the amounts of oxygen which are to be determined, and consequently erroneous results are obtained. Also. erratic Winkler data are obtained when appreciable concentrations of calcium and magnesium salts are present. The first step in carrying out a systematic study involved designing a portable dissolved oxygen apparatus which would operate in natural brines. Subsequently, this apparatus was used in three brine conditioning plants. Dissolved oxygen data obtained here, and certain corrosion rate data, illustrate the interesting behavior of oxygen in these oil field brines. APPARATUS A portable dissolved oxygen meter described in detail elsewhere,&apos; was developed specifically for use with oil field brines. It is a polarographic apparatus employing a small rotating platinum electrode (cathode) and calomel reference electrode (anode). A potential of 0.7 volts is applied across the electrodes while they are immersed in the brine to be tested. 4References given at end of paper.

Jan 1, 1952

By Richard Hamburger

The purpose of this paper is to call attention to certain methods which will shorten and simplify the calculation of plane tri-angulation. These methods, though not new & do not appear to have been properly publicized in the United States. The cotangent (or tangent) solution of a triangle permits calculation of coordinates in a smooth series of operations of the calculating machine with a minimum of notation. The semigraphical solution permits the simultaneous solution of a number of intersections, at one station, without the added burden of solving additional triangles. This in turn encourages more numerous field checks and more complete office computation than would normally be undertaken. RICHARD HAMBURGER, Junior Member AIME, is Junior Engineer, Inspiration Consolidated Copper Co., Inspiration, Arizona. TP 2798 A. Discussion (2 copies) may be sent to Transactions AIME before March 31, 1950. Tables I and I1 show the distinct advantage which the combined use of the cotangent and the semi-graphical solutions hold over, what might well be called, the standard solution. It will be shown that the positions for the entire net in fig. 1 may be calculated without computing any distances, thus saving much computation. (2) Comparison of Cotangent and Standard Solutions: To compare the cotangent method with the standard method, the notation involved in the solution of triangle 1-X-4, fig. 1, by both methods is shown. Fig. 2 shows the given information, that is, the coordinates and azimuths of Stations 1 and 4, and angles of the triangle or the azimuths from Stations 1 and 4 to Station X. (Azimuths are used here because the author feels that they are easier to handle, but bearings may be used by those who prefer them). It will be seen from the above comparison that the advantages of the cotangent solution of a triangle are: (a) rapidity, (b) full use of the calculating machine, (c) the small number of

Jan 1, 1951

By Allen Rogers

TWENTY-FIVE DOLLARS for nothing at all except a sheepskin. That to me is the effect of the New York State law for registration of engineers and the same may be said of any of the state licensing laws. Of course, if one has to practice in more than one state, he must pay a more or less equal amount for every state he works in; and yet there has been little effective protest against these laws. It would seem that the spirit which animated the Boston Tea Party is non-existent amongst engineers. Undoubtedly a good many consider, through their failure to understand the law, that the matter does not affect them. In New York State it is provided that "any person practicing or offering to practice profes-sional engineering or land surveying . . . shall be licensed as hereinafter provided." To quote further from the law: "A person practices professional engi-neering . . . who holds himself out as able to do, or who does, the work that an engineer does . . . " The cunning of the wording of this article can only be appreciated by considering that anyone calling himself an engineer falls within the definition; its liberal inter-pretation (I have not quoted the whole of it) would embrace many who do not consider themselves engi-neers. The state authorities may not construe it to include such individuals; indeed, they may possibly consider it inexpedient to extend it to include engineers of subordinate grade, but the possibility is always there and, even though an engineer be of the grade of assis-tant, he may at any time be called upon to substitute for his principal in responsible charge of the work. It is therefore clear that anyone calling himself engineer and practicing engineering must, for his own protection, apply for registration or run the risk of violating the law. Now, what is the sense of all this? We have done very well without such restrictions on the means of gaining our livelihood. If one only stops to think, there is hardly a minute of his modern existence when he is not dependent for his safety on the engineering by engineers of yesterday or today. How often is one in jeopardy through failure of engineering works, work done under the supervision of those same engineers? If all of us had to wait for our ends by such means, our average life would probably be some thousands of years. Where, then, is the point to the object declared in all these laws that the need for licensing is "to safeguard life, health and property?" Bosh!

Jan 4, 1923

By A. S. Adams

A GLANCE at the list of papers1 that have been published since 1920 on the general subject of flotation suggests the variety of ideas that exist regarding the underlying cause of the phenomenon. Among these ideas, we find several coherent theories, but none that adequately and completely explain the phenomenon. Ralston2 and Bains3 suggested an electrical theory which has to do with the attachment of mineral particles to a bubble by the attraction of unlike electrical charges. This theory has its root in the fact that a bubble of air in pure water is electrified in such a way that the surface is negatively charged while the body of the water is positively charged. This result, which was first discussed by Helmholtz, also obtains when the water contains anything except a high concentration of hydrogen ions, or ions which are trivalent or tetravalent. The theory also holds that the mineral particles have positive charges on their surfaces, and so there is attachment between bubble surface and mineral particles by the old law of electrostatics, which states that unlike charges attract.

Jan 1, 1928

By Richard Hamburger

(1) Introduction: The purpose of this paper is to call attention to certain methods which will shorten and simplify the calculation of plane tri-angulation. These methods, though not new,&apos;,2 do not appear to have been properly publicized in the United States. The cotangent (or tangent) solution of a triangle permits calculation of coordinates in a smooth series of operations of the calculating machine with a minimum of notation. The semigraphical solution permits the simultaneous solution of a number of intersections, at one station, without the added burden of solving additional triangles. This in turn encourages more numerous field checks and more complete office computation than would normally be undertaken. RICHARD HAMBURGER, Junior Member AIME, is Junior Engineer, Inspiration Consolidated Copper Co., Inspiration, Arizona. TP 2798 A. Discussion (2 copies) may be sent to Transactions AIME before March 31, 1950. Tables I and I1 show the distinct advantage which the combined use of the cotangent and the semi-graphical solutions hold over, what might well be called, the standard solution. It will be shown that the positions for the entire net in fig. 1 may be calculated without computing any distances, thus saving much computation. (2) Comparison of Cotangent and Standard Solutions: To compare the cotangent method with the standard method, the notation involved in the solution of triangle 1-X-4, fig. 1, by both methods is shown. Fig. 2 shows the given information, that is, the coordinates and azimuths of Stations 1 and 4, and angles of the triangle or the azimuths from Stations 1 and 4 to Station X. (Azimuths are used here because the author feels that they are easier to handle, but bearings may be used by those who prefer them). It will be seen from the above comparison that the advantages of the cotangent solution of a triangle are: (a) rapidity, (b) full use of the calculating machine, (c) the small number of

Jan 1, 1951

By R. C. Ruder, C. E. Birchenall

The method of decrease in surface activity was used to determine the rates of diffusion of Co" into cobalt and into nickel. Since the absorption curves for cobalt radiation were quite complex under the conditions of these experiments, the effects of geometry and surface preparation on the diffusion results were investigated. The cobalt self-diffusion coefficients obey the equation DCoco = e-61100/RT cm2 per sec. For dilute cobalt diffusing in nickel, DConi, == 1.46 e-/R&apos; cm2 er sec. AS part of the general program to measure the self-diffusion and dilute-solution diffusion rates of the iron-group metals, the diffusion coefficients of cobalt into cobalt and nickel have been measured using the radioactive isotope Co"&apos;. Self-diffusion studies in iron have been previously reported by Birchenall and Mehl.&apos; The technique of measurement used was the decrease in surface activity method described by Steigman, Shockley, and Nix.&apos; It has been determined that scattering of the measured beta radiation by the specimen matrix is significantly influenced by the condition of the surface and the counting geometry. Accurate diffusion coefficients can be calculated from the activity data provided that the specimens have plane diffusion surfaces and that the absorption properties of the emitted radiation are determined under geometrical conditions duplicating with external absorbers the absorption and scattering in a thin film at the specimen surface as nearly as possible. The cobalt used in this research was originally in the form of hydrogen reduced rondels 99.9+ pct pure. The nickel had been prepared by the carbonyl process and was found by spectrographic analysis to contain 0.03 pct Fe, 0.04 pct Co and smaller traces of other metallic elements for a balance purity of 99.9+ pet Ni. Both materials were vacuum melted and cast in rectangular ingots. Specimens 7/8x7/8x1/4 in. were machined from these ingots. The specimens were then ground to 4-0 emery paper and annealed in hydrogen for at least a day at 1200°C. Some of the specimens were used in preliminary experimentation after which their diffusion faces were machined to remove the radioactive material from the previous diffusion experiments. After grinding, the specimens were polished using an electrolytic lapping technique described by Mazia." This lapping was continued until at least 0.005 in. was removed from the diffusion surface. The final surfaces were metallographically smooth except for a few fine scratches caused by the glass cloth. A large percentage of the area was undisturbed as determined by microscopic examination. The grain diameters of the diffusion specimens varied from 0.1 to 5 mm. There were no effects due to grain boundary diffusion in the experiments

Jan 1, 1952

By M. G. Nicholas

The influence of deformation, relative movement and surface cleanliness on the strength of room -temperature "interparticle" bonds between copper surfaces has been studied. No bonding resulted when clean surfaces were merely pressed together, even under pressures of 50,000 psi. Bonding resulted, however, when clean surfaces were simultaneously pressed and moved relative to each other, some bonding occurring no matter how small the pressure or relative movement. Exposure of the clean surfaces to various chemicals inhibited bonding, none at all being produced by small relative movements. The size of the movements which first produce bonding between exposed surfaces depends on the nature of the chemical, being less than 0.002 in. for cleansing reagents and greater than 0.004 in. for lubricants, water and hydrogen sulfide. It is concluded from the experimental data that the prime requirement for bonding is the dispersal of surface films such as oxides and adsorbed contaminants. THE formation of interparticle bonds during the room-temperature compaction of powder metallurgy components greatly increases the ease of handling in subsequent production operations prior to sintering. The strength of unsintered compacts follows the same general trends as their density and hardness, but quantitative data are extremely Scarce. Quantitative correlation of the data on the overall strength of a compact with that of the individual interparticle bonds is virtually impossible due to the extremely complex geometry of powder compacts. Qualitatively, however, the strengths of unsintered compacts can be correlated with variations in parameters known to influence the extent of cold bonding, and hence interparticle bonding, such as surface cleanliness, relative movement, and deformation of the mating surfaces. Kuzmic and seelig4 found that contamination of powder particle surfaces with lubricants reduced the strength of unsintered iron and copper compacts. Interparticle shear has been shown to promote bonding by Train and Hersey7 while Gregory has shown that die rotation is beneficial. Eilender and schwalbe6 concluded that most bonding occurred during the early stages of pressing iron powder compacts when interparticle shear is one of the principal processes occurring. mile there can be little doubt that these and other factors, such as particle size and shape, affect the extent of interparticle bonding produced by compaction, evaluation of the influence of individual factors is not easy. Particle deformation and relative movement, for example, occur simultaneously during compaction, making any precise measurement of their relative influences difficult. Because of these and other difficulties encountered in studying interparticle bonding in actual powder compacts, the approach adopted in this study was to

Jan 1, 1963