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By Robert P. Koenig

FOR the first time other than on occasion of war the people of the United States are experiencing full-scale participation in world affairs. Public concern has seldom been so involved with conditions and events beyond our own continental limits. Our interest is not wholly of recent origin. Over the years the activity of the United States as a world power and an important trading nation brought about the widening of our political interests and the progressive interrelation of our economy with that of the rest of the world. Some may see in our present phase of world-wide activity the natural consequence of our continued growth. Such observers must also be aware that within recent years our importance in world affairs has been considerably increased. For within the space of an extremely short period events have occurred that have literally jet-propelled the United States into the role of a leading participant in the conduct of world affairs. Little of the choice of this role was left to us. The decline of power in western Europe, the ascendancy between the Elbe and the Pacific shore of an obviously antagonistic force, our earnest endeavor to secure international control of atomic energy, the necessity of providing relief and rehabilitation to war-ravaged areas, and the police work that must be done in occupied territories are problems which have risen in great measure without our help-but they cannot be solved without it.

Jan 1, 1948

By J. D. Sullivan, Chester R. Austin, J. L. Nunes

It is characteristic of most shales and surface clays that a bloated or vesicular structure is produced by burning to a sufficiently high temperature, usually about 150° to 200°F. above the normal maturing temperature used when making common brick of the same material. Early investi-: gators recognized this phenomenon and attributed it to the release or expansion of gases in the vitrified piece. A number of theories have been advanced on the source of the gas and the manner in which it is evolved, but none has been proved conclusively. T. E. Jackson's1 early theory that bloating was due to oxygen evolved by ferric oxide in forming ferrous oxide or ferrous silicate was never substantiated by - experimental work. Orton2 thought this explanation unlikely, as all clays should bloat at the same temperature, if this were true. He found that clays bloated in the range from IIoo° to 17oo°C. Also, many clays containing iron did not bloat at all, but fused. Orton also stated that oxida- tion of different types of carbon was a source of gas during burning of clay and should be expelled before vitrification was reached. Seger3 said that he had dissolved ferric oxide in glass with no apparent evolution of gas. Matson4 came to the conclusion that ferruginous clays burned ' to vitrification in an oxidizing atmosphere did not have the iron in a ferrous form. According to Wilson,= the gases responsible for bloating might be entrapped air, water, sulphur dioxide, carbon monoxide, oxygen, and hydrocarbons. He spoke of two causes of bloating: (I) incomplete oxidation below the vitrification temperature, and (2) decomposition of compounds and evolution of gases above the vitrification temperature. Decomposition of calcium sulphate was given as the principal example of the latter. Bleininger and Montgomery0 stated that if any time after vitrification began the evolution of gaseous matter was rapid enough so that pressure was produced within the clay, bloating was certain to take place, and a vesicular structure would be formed. They recognized that initial structure, rate of heating, kiln atmosphere, and many other variables affected bloating. Work done by the Emergency Fleet Corporation7 indicated that clays suitable for bloating should be high in compounds of metallic oxides, carbon, sulphur, sodium, potassium, or other equivalent compounds, which either act as a flux or give off gas. Orton2 studied the chemical status of the carbon, iron, and sulphur in clays during various stages of burning, using a Huron shale that bloated under oxidizing or reducing conditions. He found that only a small amount of sulphur remained in the clay and that it could be detected only by dissolving the clay in hydrofluoric acid; i.e., the sulphur was in combination with the silica. orton said that this sulphur was probably in the form of iron sulphide dissolved in the glass phase. The iron sulphide was not broken down by heating, but was dissolved in the basic slag or glass,

Jan 1, 1942

By J. D. Sullivan, Chester R. Austin, J. L. Nunes

It is characteristic of most shales and surface clays that a bloated or vesicular structure is produced by burning to a sufficiently high temperature, usually about 150° to 200°F. above the normal maturing temperature used when making common brick of the same material. Early investi-: gators recognized this phenomenon and attributed it to the release or expansion of gases in the vitrified piece. A number of theories have been advanced on the source of the gas and the manner in which it is evolved, but none has been proved conclusively. T. E. Jackson's1 early theory that bloating was due to oxygen evolved by ferric oxide in forming ferrous oxide or ferrous silicate was never substantiated by - experimental work. Orton2 thought this explanation unlikely, as all clays should bloat at the same temperature, if this were true. He found that clays bloated in the range from IIoo° to 17oo°C. Also, many clays containing iron did not bloat at all, but fused. Orton also stated that oxida- tion of different types of carbon was a source of gas during burning of clay and should be expelled before vitrification was reached. Seger3 said that he had dissolved ferric oxide in glass with no apparent evolution of gas. Matson4 came to the conclusion that ferruginous clays burned ' to vitrification in an oxidizing atmosphere did not have the iron in a ferrous form. According to Wilson,= the gases responsible for bloating might be entrapped air, water, sulphur dioxide, carbon monoxide, oxygen, and hydrocarbons. He spoke of two causes of bloating: (I) incomplete oxidation below the vitrification temperature, and (2) decomposition of compounds and evolution of gases above the vitrification temperature. Decomposition of calcium sulphate was given as the principal example of the latter. Bleininger and Montgomery0 stated that if any time after vitrification began the evolution of gaseous matter was rapid enough so that pressure was produced within the clay, bloating was certain to take place, and a vesicular structure would be formed. They recognized that initial structure, rate of heating, kiln atmosphere, and many other variables affected bloating. Work done by the Emergency Fleet Corporation7 indicated that clays suitable for bloating should be high in compounds of metallic oxides, carbon, sulphur, sodium, potassium, or other equivalent compounds, which either act as a flux or give off gas. Orton2 studied the chemical status of the carbon, iron, and sulphur in clays during various stages of burning, using a Huron shale that bloated under oxidizing or reducing conditions. He found that only a small amount of sulphur remained in the clay and that it could be detected only by dissolving the clay in hydrofluoric acid; i.e., the sulphur was in combination with the silica. orton said that this sulphur was probably in the form of iron sulphide dissolved in the glass phase. The iron sulphide was not broken down by heating, but was dissolved in the basic slag or glass,

Jan 1, 1942

By B. F. Fackenthal

At the session of the Bethlehem, Pa., meeting of the Institute, held in the Durham Cave, at Durham Furnace, on the afternoon of May 20, 1886, I exhibited some specimens of a fibrous white efflorescence which had exuded from the pig-iron at that time being made at Durham Furnace. As some of the members expressed an interest in the matter, I promised to have complete analyses made, and to report the result in a paper to the Institute. The presentation of the paper has been long delayed, but there appears to be no other literature on this subject, and it may still be of interest. The efflorescence was found to exude from the pig-iron where the pigs were broken hot from the sow; the entire fracture of both pigs and sow often being entirely coated with this material. Sometimes there was only a white surface, as if the ends had been daubed with white paint; but in most cases the material was found in small globules and in thin sheets. If the iron had been broken a little too hot, arid in consequence had " bled " on separating from the sow, some of the efflorescence would be found deposited 011 the iron-drippings, and on the incrustations of sand in the pig-bed. The globules were irregular in shape, some of them equivalent in mass to spheres three-eighths of an inch in diameter, but most of them much smaller. The thin sheets were also irregular in shape, and, although they were not porous, were often riot thicker than a spider-web. Some of them were produced by the peeling-off' of the thin coating on the pigs above referred to. They were opalescent in appearance, and some of them had an area equivalent to two square inches; but the largest pieces would fall apart in handling. Several ounces of the efflorescence could often be picked up, or scraped off the pigs, after each cast.

Jan 1, 1901

United Engineering Trustees, Inc. W. D. B. MOTTER, JR., '40 A. L. QUENEAU, '41 ALBERT ROBERTS, '39 The Engineering Foundation GEORGE D. BARRON, '40 F. F. COLCORD. '42 A. L. QUENEAU, '41

Jan 1, 1939

By E. R. Atkins, G. H. Smith

Results of laboratory tests are presented to show that lire value of "m", in the Archie expression dernlined by the shapes of the particles in the system. Tile value of m "the shape factor", is constant for a system of particles of a given shape for a range of F - + values. Applying this concept, one can predict F - + relationships for mixtures of particles with different shapes, and these predicted relationships are useful in electric log interpretation. It is suggested that an equation of the form 1/F -10mcan be used to describe the properties of natural formations containing varying amounts of sand and clay. From this work and values of "a" and "m" reported in the literature, it appears that in many cases rocks in the same geological horizon have a common primary porosity but contain varying amounts of a particular clay. It is concluded that the equation can be applied to a rock-water system only when values of "a" and "m" have been established for the particular system. INTRODUCTION The petroleum literature contains many reports of the results obtained by determining formation resistivity factor F and porosity + of rock samples from oil fields all over the world. The usual practice is to use data from a large number of samples from a number of fields to find an average relationship between F and +. Several such average relationships have been advanced. In the absence of data on a particular formation or field, it has been the practice to use the average relationships to give a rough approximation of the F - + relationship. The purpose of this paper is to report on basic relationships that exist between F and + for naturally occurring particles in water solutions. Other workers' have found the same relationships apply to the diffusion of hydrogen through packed beds of dry particles. In the work discussed here, relationships for application to unconsolidated sands or shales containing mix- tures of particle shapes are derived. These relationships, developed for unconsolidated formations, may apply to consolidated formations. EXPERIMENTAL To evaluate F- relationships for unconsolidated rocks, the results of laboratory measurements on simple slurries of clay or sand will be used. Such laboratory studies are concerned with the electrical behavior of water-containing rocks. The wet rock constituents are electrically similar in slurries and in rocks. Archie2 defined formation resistivity factor as All resistance measurements were made using a 1,000-cycle impedance bridge with an oscilloscope as the null detector." The accuracy of this bridge was better than * 0.15 per cent. For the particular apparatus employed, no additional reactance was required to achieve balance for samples with resistances between

By Harold Markus, Arthur H. Grobe, Gerhard Derge

THE high corrosion resistance possessed by tin under most circumstances, combined with its generally satisfactory appearance and useful physical properties, has led to many and varied uses for the metal. These uses have been partly limited by the fact that tin is an expensive metal, therefore many applications have been developed in which tin has been employed in combination with lead, either by coating, as in tin-lined collapsible tubes, or by the formation of alloys containing various proportions of tin-rich and lead-rich phases, as terne plate. A detailed knowledge of the corrosion characteristics of the tin-lead couple therefore is of general interest and has become specially important at the present time, when every effort is being made to conserve tin as much as possible. The present study. has been limited to carbonate solutions with a pH range from 8.4 to 11.2 so that the results may be related to earlier work on the corrosion of tin and its alloys.1-3,6 In these papers, the effects of a number of anion and cation additions to these solutions have been observed. APPARATUS AND METHOD The electrodes for the corrosion cell were cut from rolled sheet about 1/16 in. thick. The length of all specimens was held constant at 7 in., while the width was varied from 1/2 to 2 in. These electrodes were fastened to brass electrode supports, which were attached to rubber stoppers fitting into tall-type one-liter Pyrex beakers that contained the electrolyte. The lead electrodes were prepared from Omaha pig* and the tin was rolled from a slab of Chempur.? After cutting to size, the sheets were polished with No. I emery paper and cleaned with carbon tetrachloride. The edges, back and upper parts of the specimen were coated with a synthetic lacquer, which was supplemented with beeswax for the lead electrodes. The binding posts were coated with beeswax after the electrodes had been damped. The pH of the electrolyte was controlled? by adjusting the ratio of carbonate to bicarbonate. Approximately 600 ml. of electrolyte was used in each beaker. The entire assembly was placed in an oil bath thermostatically adjusted to operate at 30°C. ± 0.10. Potentials were measured against a saturated calomel electrode connected. to the cell by an agar-agar salt bridge. The carbonate solution used in the salt bridge was the same as that used in the corrosion cell. Currents were measured with a milliam-

Jan 1, 1942

By A. Tonejc, A. Bonefacic

As can be seen from the phase diagram A1-W1 the equilibrium solubility of tungsten in aluminum is practically nil at room temperature. By quenching from the liquid state (50,000°C per sec), Varic, Burov, and Kolesnicenko2 obtained A1-W solid solutions up to 0.15 at. pct W. The quenched alloys were in the form of foils, 0.2 to 0.3 mm thick. Considering the results of Duwez and Willens,3 it is obvious that this thickness, which makes impossible a sufficiently rapid quenching, was the main reason for the relatively low content of tungsten dissolved in aluminum found by varic.2 he present note shows that the metastable solubility of tungsten in aluminum can be appreciably extended in aluminum-rich A1-W alloys. The quenching technique and the procedure employed for the preparation of the alloys have been described previously.475 The resulting quenched flakes varied in thickness from 1 to 20 µm from experiment to experiment. However, the measurements of the lattice parameters were carried out only with flakes thinner than 5 µm. The areas of quenched flakes were between 0.1 and 15 mm2. The quenched flakes were placed into a 0.3-mm glass capillary tube which was then mounted in a 114.6-mm-diam Debye-Scherrer camera. Straumanis asymmetric film position and nickel-filtered CuKa radiation were used. The lattice spacings were computed taking X(CuKa1) = 1.54050A for resolved and ?(CuKa) = 1.54178A for unresolved doublets. All specimens were rotated at room temperature, 26o +2°C. The lattice parameters were estimated from extrapolation against the Nelson-Riley function. It was estimated that the error in the lattice parameter of the measurements on a single film lies within +0.0004A for lower and about +0.001A for higher concentrations of tungsten. The lattice parameters of the metastable solid solutions A1-W are plotted vs the concentration of tungsten in Fig. 1 together with the parameters measured by previous investigators.' Each point of the present measurements represents a determination of the lattice spacing on different quenched flakes, for a given concentration of tungsten. With experimental accuracy, the lattice parameters of the metastable solid solutions fall on the straight line passing through the already known data.' As estimated from the uncertainties in the lattice spacings of the solid solutions, the alloys were homogeneous within 0.1 at. pct W. The solubility of tungsten in aluminum-rich A1-W solid solutions obtained by a very rapid quenching technique is increased to about 0.95 at. pct W. This value is 6 times greater than the amount known up to now. -he lattice parameters of the resultant aluminum solid solutions with higher concentrations of tungsten than 0.95 at. pct W did not remain constant AUGER electron spectroscopy has been used to clarify the role of impurities in the embrittlement of AISI 3340 steel. Analysis of fracture surfaces has shown that the embrittled condition is correlated with appreciable antimony segregation at grain boundaries. The low temperature (400" to 600°C) temper embrittlement of low alloy steels containing various combinations of Cr , Ni , Sb , Mn , P , Sn , and As has been examined extensively for many years. General reviews of the area have been made by McMahon1 in 1968, LOW' in 1959, woodfine3 in 1953, and Holloman4 in 1946. Recent work by Low, Stein, Turkalo, and LaForce5 has done much in separating the alloy and

Jan 1, 1970

By C. R. Ramachandra, C. C. Patel

Flotation of chalcopyrite from a low grade ore was studied by using different xanthates and dixanthogens as collectors and by conditioning the flotation pulp with oxidizing gaseous systems. The improvement in the recovery of chalcopyrite with the oxidizing systems was mainly due to the auto-activation of chalcopyrite, leading to the enhanced adsorption of xanthates and dixanthogens even when the latter were formed by oxidation of the xanthates. With air or oxygen as oxidizing system, the amount of ethyl xanthate required at pH 8.5 was much less than normally employed in the industry, the recovery being 97-99% of chalcopyrite with a concentrate of 24% copper. With isopropyl and isoamyl xanthates, the recovery was improved but the grade was lowered. By conditioning the pulp with air-CO2 or oxygen-CO2 mixture, the recovery was lowered with ethyl xanthate only, mainly due to the depressant action of bicarbonate formed. Flotation with dixanthogens gave cleaner concentrates of chalcopyrite. because iron pyrite did not float with these collectors. Of the dixanthogens tried, diisopropyl dixanthogen gave the highest recovery, 99% chalcopyrite with a concentrate containing 28.5 to 30% copper, when the pulp at pH 8.5 was condi-tioned with air. Isopropyl dixanthogen was found to be the best collector of all the xanthates and dixanthogens studied. It was found that the adsorbed ethyl, isopropyl and isoamyl xanthates at chalcopyrite surface, activated by cupric sulfate, and at iron pyrite surface were oxidized to the corresponding dixanthogens to different degrees in presence of air, oxygen, air-carbon dioxide mixture and oxygen-carbon dioxide mixture.' The dixanthogen formed at chalcopyrite surface was, however, firmly adsorbed while that at iron pyrite surface was easily desorbed. Since dixanthogens formed have greater hydrophobicity than the corresponding xanthates, as revealed by contact angles,1,2 the former were expected to improve the flotation results. It was, therefore, thought desirable to find out the effect of air, oxygen, air-carbon dioxide mixture and oxygen-carbon dioxide mixture on the selective flotation of chalcopyrite when individual xanthates were used as collectors. The effect of direct use of dixanthogens as collectors on the selective flotation of chalcopyrite was also investigated. For these studies, low grade chalcopyrite ore, received from the Indian Copper Corp., Ltd. (I.C.C.), Ghatsila, Bihar, was employed. At the milling plant of the I.C.C., chalcopyrite is floated at a pH of 8.5, employing ethyl xanthate as collector. EXPERIMENTAL Materials Employed: XANTHATES - Ethyl, isopropyl and isoamyl xanthates of potassium were prepared in a pure state by the methods described earlier.4 A 0.03% aqueous solution of a xanthate was freshly prepared in air-free distilled water for flotation studies. DIXANTHOGENS - Diethyl, diisopropyl and diisoamyl dixanthogens were prepared by the oxidation of xanthates by iodine and purified by extraction with petroleum ether. A 0.03% alcoholic solution of dixanthogen was used as a collector. FROTHER - A 0.2% solution of pine oil in ethyl alcohol was employed. SODIUM CARBONATE - A 0.4 N solution was used. ORE - The composition of the -100 +200-mesh size (Tyler standard) powdered ore, as determined by standard methods of analysis, was: copper 1.57%, iron 10.29%, sulfur 3.15% and acid insolubles 66.10%. Iron present as chalcopyrite (CuFeS2) was 1.38%, while that present as iron pyrite (FeS,) was 1.37%. Both chalcopyrite and iron pyrite were found to be liberated from the gangue minerals and from each other, as observed under a microscope. Flotation of Chalcopyrite with Xanthates in Presence of Different Gaseous Systems: Fifteen grams of -100 + 200-mesh size ore were shaken well with 100 ml of distilled water. The pH of the pulp was adjusted to 8.5 by the addition of sodium carbonate solution. Then 0.1 ml of xanthate solution (0.005 lb xanthate per ton of the ore) was mixed with the pulp, and the latter together with washings transferred to a

Jan 1, 1963

By James Terry Duce

The gross production on the Island of Sahreirl during 1944 was approximately 6,700,000 U. S. bbl. No additional wells were drilled in the field during the year, but a number that were plugged off during the critical days of the war were brought back on production. This work is continuing. The construction of the extension of the refining plant was continued during the year and the new crude still was started in November. In Arabia, the production for the year 1940 was 5,074,838 U. S. bbl. Four wells were completed in Dammam field and all were commercial producers. Production for 1941 was 4,310,110 U. S. bbl. Seven more commercial producing wells were completed in Dammam field, and Well No. I at Abqaiq was complcted at 6180 ft. and was also a commercial producer. In 1942 production was 4,530,492 U. S. bbl. Abqaiq No. 2 was drilled to 5785 ft. but was left standing because of mechanical difficulty. The 1943 production was 4,868,- 184 with one well drilled, Abqaiq No. 3 completed at 6488 ft. and a commercial producer. Total production in Arabia for the year 1944 was around 7,800,000 U. S. bbl. and at the close of the year was running at approximately 40,000 bbl. per day. The small refinery, built in 1939, at Ras Tanura was in operation in the fall and a new refinery is being constructed. Only three wells were completed during the year—the El Jauf well in Northern Arabia (completed at 10,974 ft.) which did not bring in commercial production and Wells No. 4 (completed at 6270 ft.) and No. 5 at Abqaiq (completed at 6751 ft.), which were brought in as substantial commercial producers. Production for the year was entirely from the Dammam field. In this field, some of the wells that had been plugged off early in the war were brought back in production and this work is continuing. At the close of the year, one well was drilling in the Abqaiq field and an additional well was drilling at Qatif, the latter being a wildcat. Neither of the wells in question had reached producing horizons on the first of January.

Jan 1, 1945

By Paul T. Benson

MOST important of the various departments of a custom smelter, so far as the financial welfare of the plant and the confidence of shippers are concerned, is that responsible for correct weights, accurate moisture sampling, and the obtaining of control samples that are strictly representative of the lot of ore from which they come. Treatment rate schedules are based on the metal content of ores received, reduced to dry weight. These rates must be low enough to keep the ship- per from taking his business else- where and still must allow the smelter a profit. Assay results, likewise, must satisfy the shipper, but if they show too high a metal content for the ore they represent, the smelter will actually lose money. It is always considered, and constant checks through umpire assays prove, that laboratory results are closely correct, so the bur- den of the plant profit and loss and the satisfaction of the shipper rest squarely upon the sampling department.

Jan 1, 1936

United Engineering Trustees, Inc. W. D. B. HOTTER, JR., '44 A. L. QUENEAU, '45 ALBERT ROBERTS, '43 The Engineering Foundation GEORGE D. BARRON, '44 F. F. COLCORD, '46 A. L. QUENEAU, '45

Jan 1, 1942

United Engineering Trustees, Inc. W. D. B. MOTTER, JR., '40 A. L. QUENEAU, '38 ALBERT ROBERTS, '39 The Engineering Foundation GEORGE D. BARRON, '40 F. F. COLCORD, '38 A. L. QUENEAU, '38

Jan 1, 1937

By D. Turnbull, J. H. Hollomon, J. C. Fisher

The concepts of nucleation and of growth have adequately described the isothermal phase transformations to which they have been applied.ls2 However, these concepts have not yet been used successfully to describe the kinetics of a number of transformations that are not observed to take place isothermally. A typical reaction of this type is the austenite to martensite transformation in steels, for which the new phase appears only during cooling of the parent phase. If the cooling is interrupted, transformation ceases; yet had the cooling continued, transformation would also have continued. Nuclei of a new phase do not leap into existence all at once by the simultaneous cooperation of a large number of atoms or molecules of the parent phase; rather they are formed at finite rates by gaining or losing atoms one at a time from the surrounding materiaL3,4 Further thermo-dynamic considerations require a finite concentration of small transitory nuclei of all unstable phases to exist at equilibrium in a stable phase.= For steel in particular, nuclei of ferrite (a iron) exist at equilibrium in austenite (y iron) at temperatures where austenite is the stable phase. If a high-temperature phase a be cooled sufficiently rapidly from temperature TI above the a-ß equilibrium temperature To, to temperature T-1 below To where ß is the stable phase, the equilibrium distribution of ß nuclei corresponding to the high temperature will be retained. There are two limiting possibilities of particular interest: I. The steady state rate of nucleation of ß may be appreciable at T_1, and may require a concentration of sub-critical nuclei exceeding that retained from the high temperature. Time will be required then for the concentration of nuclei to build up to the steady state value, and an induction period will be observed during which the rate of nucleation will increase to the steady state value. 2. The steady state rate of nucleation of ß may be negligible at T-l, while the critical size for continuous growth of ß nuclei, which decreases with increased subcooling of the a phase, may reach a value so small that some. of the retained high-temperature nu-

Jan 1, 1949

By M. C. Leverett, M. E. True, W. B. Lewis

This paper states the theory underlying the design of two kinds of dimensionally scaled models of parts of idealized oil fields. One of these simulates an oil well and its surrounding sand for a distance of 16 ft. radially from the well. The other model simulates linear flow through layered sands. Construction and operation of the models are described and typical data are given. The unique features in the design of the models are: (I) the treatment of the permeability-viscosity quotient as a single variable and (2) the use of previously reported experimentally developed relations between relative permeability and saturation and capillary pressure, saturation, porosity, permeability and interfacial tension. The models at present simulate flow of oil and water only, through unconsolidated sands. They are superior to unscaled models, which may give rise to erroneous conclusions. The models are designed to study the desirability of various methods of well completion and the effects of various factors on recovery of oil from layered sands. Introduction Recent work on the fundamental behavior of flowing mixtures of fluids in sands has resulted in the development of some new theory in this field, much of which has been presented in previous papers.l-4 However, the application of this theory to the behavior of oil wells or oil fields has proved too complicated for ordinary mathematical techniques, except in very highly simplified cases. A practical solution to this problem appears therefore, to lie in the use of dimensionally scaled models of elements of oil fields. The object of this paper is, first, to present the theoretical and experimental basis of the design of such models, and, second, to describe their construction and operation. Experiments now under way on the models already built will yield material for other reports, which will be devoted to interpretation of the results in terms of oil-field behavior. So far, simple dimensional models of two kinds have been built and are being operated. These models represent different parts of an idealized oil field but obey the same underlying theory. The only fluids represented are oil and water, since certain questionable approximations are necessary for gas-liquid systems. General Theory Dimensional models have been used in other fields for a long time, and their theory is adequately given in the literature. 5 Here, it suffices to state that each physical element entering into a dynamic relation may be given a definite description in terms of three fundamental, but arbitrarily chosen, dimensions. These usually are mass, length, and time, symbolized here by the small letters m, I, and t. Two systems are said to be dimensionally similar or dimensionally scaled if for each element in one system there is a corresponding element in the second system and the ratios of the numerical magnitudes of corresponding elements are constant for all elements of the same dimensional type.

Jan 1, 1942

By W. B. Lewis, M. E. True, M. C. Leverett

This paper states the theory underlying the design of two kinds of dimensionally scaled models of parts of idealized oil fields. One of these simulates an oil well and its surrounding sand for a distance of 16 ft. radially from the well. The other model simulates linear flow through layered sands. Construction and operation of the models are described and typical data are given. The unique features in the design of the models are: (I) the treatment of the permeability-viscosity quotient as a single variable and (2) the use of previously reported experimentally developed relations between relative permeability and saturation and capillary pressure, saturation, porosity, permeability and interfacial tension. The models at present simulate flow of oil and water only, through unconsolidated sands. They are superior to unscaled models, which may give rise to erroneous conclusions. The models are designed to study the desirability of various methods of well completion and the effects of various factors on recovery of oil from layered sands. Introduction Recent work on the fundamental behavior of flowing mixtures of fluids in sands has resulted in the development of some new theory in this field, much of which has been presented in previous papers.l-4 However, the application of this theory to the behavior of oil wells or oil fields has proved too complicated for ordinary mathematical techniques, except in very highly simplified cases. A practical solution to this problem appears therefore, to lie in the use of dimensionally scaled models of elements of oil fields. The object of this paper is, first, to present the theoretical and experimental basis of the design of such models, and, second, to describe their construction and operation. Experiments now under way on the models already built will yield material for other reports, which will be devoted to interpretation of the results in terms of oil-field behavior. So far, simple dimensional models of two kinds have been built and are being operated. These models represent different parts of an idealized oil field but obey the same underlying theory. The only fluids represented are oil and water, since certain questionable approximations are necessary for gas-liquid systems. General Theory Dimensional models have been used in other fields for a long time, and their theory is adequately given in the literature. 5 Here, it suffices to state that each physical element entering into a dynamic relation may be given a definite description in terms of three fundamental, but arbitrarily chosen, dimensions. These usually are mass, length, and time, symbolized here by the small letters m, I, and t. Two systems are said to be dimensionally similar or dimensionally scaled if for each element in one system there is a corresponding element in the second system and the ratios of the numerical magnitudes of corresponding elements are constant for all elements of the same dimensional type.

Jan 1, 1942

By H. L. Marcus, P. W. Palmberg

As can be seen from the phase diagram A1-W1 the equilibrium solubility of tungsten in aluminum is practically nil at room temperature. By quenching from the liquid state (50,000°C per sec), Varic, Burov, and Kolesnicenko2 obtained A1-W solid solutions up to 0.15 at. pct W. The quenched alloys were in the form of foils, 0.2 to 0.3 mm thick. Considering the results of Duwez and Willens,3 it is obvious that this thickness, which makes impossible a sufficiently rapid quenching, was the main reason for the relatively low content of tungsten dissolved in aluminum found by Varic.2 he present note shows that the metastable solubility of tungsten in aluminum can be appreciably extended in aluminum-rich A1-W alloys. The quenching technique and the procedure employed for the preparation of the alloys have been described previously.475 The resulting quenched flakes varied in thickness from 1 to 20 µm from experiment to experiment. However, the measurements of the lattice parameters were carried out only with flakes thinner than 5 µm. The areas of quenched flakes were between 0.1 and 15 mm2. The quenched flakes were placed into a 0.3-mm glass capillary tube which was then mounted in a 114.6-mm-diam Debye-Scherrer camera. Straumanis asymmetric film position and nickel-filtered CuKa radiation were used. The lattice spacings were computed taking X(CuKa1) = 1.54050A for resolved and ?(CuKa) = 1.54178A for unresolved doublets. All specimens were rotated at room temperature, 26" +2°C. The lattice parameters were estimated from extrapolation against the Nelson-Riley function. It was estimated that the error in the lattice parameter of the measurements on a single film lies within +0.0004A for lower and about +0.001A for higher concentrations of tungsten. The lattice parameters of the metastable solid solutions A1-W are plotted vs the concentration of tungsten in Fig. 1 together with the parameters measured by previous investigators.' Each point of the present measurements represents a determination of the lattice spacing on different quenched flakes, for a given concentration of tungsten. With experimental accuracy, the lattice parameters of the metastable solid solutions fall on the straight line passing through the already known data.' As estimated from the uncertainties in the lattice spacings of the solid solutions, the alloys were homogeneous within 0.1 at. pct W. The solubility of tungsten in aluminum-rich A1-W solid solutions obtained by a very rapid quenching technique is increased to about 0.95 at. pct W. This value is 6 times greater than the amount known up to now. -he lattice parameters of the resultant aluminum solid solutions with higher concentrations of tungsten than 0.95 at. pct W did not remain constant AUGER electron spectroscopy has been used to clarify the role of impurities in the embrittlement of AISI 3340 steel. Analysis of fracture surfaces has shown that the embrittled condition is correlated with appreciable antimony segregation at grain boundaries. The low temperature (400" to 600°C) temper embrittlement of low alloy steels containing various combinations of Cr, Ni, Sb, Mn, P, Sn, and As has been examined extensively for many years. General reviews of the area have been made by McMahon1 in 1968, LOW' in 1959, woodfine3 in 1953, and Holloman4 in 1946. Recent work by Low, Stein, Turkalo, and LaForce5 has done much in separating the alloy and

Jan 1, 1970

By M. Metzger, J. Intrater

IN the large number of important studies on high-purity aluminum (e.g., recrystallization and grain growth, creep, internal friction), it does not seem to have been generally recognized that the iron content, despite its very low figure, has a strong influence on a number of properties. In part, its influence is due to the very low solubility of the Fe-A1 6 phase. For aluminum of about 99.99 pct purity, the iron content may be 0.001 to 0.004 pct. For values in this range, a second phase will be present below 410" to 480 °C. This was determined by extrapolation of a log solubility vs inverse temperature plot of the solid solubility data of Edgar.' One consequence is the inhibition of grain coarsening below the solubility limit. This is shown in Table I, which gives, for three iron contents, the annealing temperature required for the absence of grains smaller than 1/2 mm average diameter together with the minimum temperature for the presence of some grains larger than 2 mm diameter. The specimens were 1/4x 1 1/2-in. strips cut from hard-rolled 1/16-in. sheet supplied by the Aluminum Co. of America.

Jan 1, 1954

By H. M. Chance

Probably no other prosperous mining district is so little known as the Black Hills. The name leads one to assume that the district is a rolling country, consisting of more or less insignificant hills. Nothing could be more untrue, as the Black Hills is an elevated region rising to heights of 7000 and 8000 feet above sea-level, and broken by deep gorges and ravines. It is, in fact, a mountainous country in all that that term implies ; but the cañons and gorges are of such a character that the country is easily penetrated by railroad-lines, and good wdgon-roads exist to-day, affording access to every portion of it. Aside from the stampede to the Black Hills country in 1876, when gold-placers were discovered, and 15,000 or 20,000 people became infected with the mining fever, the region has never had a mining " boom." Quartz-mining commenced in 1877 or 1878, and has been successfully prosecuted ever since; the output of gold steadily growing, until at present the yield is about $7,000,000 annually. This great production is about equally divided between two entirely different classes of deposits. The first class, comprising the so-called quartz or free-milling ores (of which the Homestake mine is the principal producer), are veins of generally steep dip, in the older metamorphosed rocks, and similar to the veins worked in other mining districts. The second class of mines is located in what is known as the " siliceous gold-belt." The Siliceous Gold-Belt. This belt, more particularly to be described in this paper, lies in the immediate vicinity of Deadwood and Lead City, and covers an area 6 or 7 miles in length by 3 or 4 miles in width. The formation in which the siliceous ores are found is a nearly horizontal series of sandstones and shales, generally

Jan 1, 1901

By Zay Jeffries

IT has been known for a number of years that certain aluminum alloys could be hardened by quenching from a temperature of about 500° C. Immediately after quenching the total increase in hardness is not marked, but the hardness increases gradually so that after about 4 days, it has reached a maximum. The actual increase in hardness probably continues for weeks or even months, but in order to detect the differences after 4 days, it is necessary to make tests at rather long intervals. So far as is known to the authors, Alfred Wilm was the first to discover these properties in aluminum alloys.1 The aluminum-copper alloys are amenable to this treatment and the addition of magnesium makes the heat-treatment effect more pronounced. Until recently heat treatment of aluminum alloys has been confined to the worked alloys in the form of sheet or extruded products. The alloy that has been most used in this connection is known commercially as duralumin and has about the following composition: copper not exceeding, 6 per cent.; magnesium not exceeding, 2 per cent.; manganese not exceeding, 1 per cent.; commercial aluminum,2 balance. A typically good alloy in this range consists of: copper, 4 per cent.; magnesium, 0.5 per cent.; manganese, 1 per cent.; commercial aluminum, balance. This alloy can be rolled into sheets or extruded; and in this condition it can be heated in the ordinary furnace atmosphere to a temperature near 500° C. and quenched in water. After about 4 days it will have the following physical properties: tensile strength 55,000 to 60,000 lb. per sq. in. (3866 to 4218 kg. per sq. cm.); elongation in 2 in., 15 to 20 per cent. No harmful effects of the furnace gases or even the air, if the heating is affected in an electric furnace in an air atmosphere,

Jan 9, 1919